Rabu, 07 Desember 2016

colon sintomas de cancer

[title]

>> good afternoon. i just want to mention that the final exam of this course, which i've been touting for the past couple week is actually electronically on the website. you just google demystifying medicine or go to the list serve.

if you've been to at least 50% of the sessions and you pass the exam which is not going to stress you and maybe you'll learn something in the process. you can take it over and over again, you'll get a certificate saying you've been here and we're grateful for you.

so next week is reall the last session and we've collected a bunch of questions that some of you submitted about things that you would like to hear from the speakers. now the speaker are an extraordinary group. it's the institute director of

ninds, the institute director of the national institute of mental health. john gallon who heads the clinical center, and bob alban from the national heart and lung institute. now the whole point of it is that this will be sort of a free

wheeling discussion because what you want them, people have asked them to talk about are what are the opportunities as they see it in their fields where the exciting expanding areas which may be of interest to you all and what opportunities may exist for ph.d. scientists in

particular. they are very realistic people. they'll talk in terms of what the problem are today as well. at any rate, it's up to whoever comes, and usually we've had a very good crowd, a very active people. last thing.

if anybody has any comments, suggestions, criticisms, good, bad indifferent about the course itself, we'd all appreciate hearing from you. particularly suggestions of topics and people whom you might like to have participate next year.

okay. so this is the last time. no, next week you'll see it again. the brooklyn bridge which is sort of the symbol of what we're trying to do to link cutting edge opportunities, are excitement and scientific

development. and major health problems. sometimes it's the science that drives the clinical. in today, it's as i see it, it's sort of an extraordinary coming together, a coming together of exciting advances in understanding what the

mitochondria does other than control atp. those of you used to seeing pictures in a textbook laid back, those mitochondria weren't moving, they were just sitting there. it turn out of course in biology everything is moving.

our second speaker today, jennifer lippincott-schwartz, i think one of the main themes of jennifer's really exciting studies in many areas of cell biology is the dynamic nature of the processes going on within the cell. and the fact that you have your

hands tied, if you are looking at these only from one dimension. so her laboratory blends biochemistry, wide cell imaging using an incredible array of technologies, some of which were developed in her laboratory. biophysics.

and increasingly, a somewhat pathophysiologic orientation to what the problems are. and then on the other hand of the prejudice -- bridge, by the way this is the brooklyn bridge, the most famous bridge in the world. on the other side of the bridge

in medicine, this is a beautiful example of the fact there have been enumerable descriptions. usually in the pediatric or young adult literature of patients who have a myriad of symptoms. not always but usually focused on impairments of metabolism of

energy but it may involve neurological features, sometimes solid organ features. energy, growth. a whole array. and the literature through many years is filled with these and they have people's names attached because they are

usually the clinicians who describe them. and it's precisely the accuracy of those descriptions that has now made it possible with the tools of genomics to begin to ask questions at a fundamental level of what are these diseases and what are the gene mutations

coding in the way of a protein and what does that protein do in normal metabolism, whether it's in the brain or elsewhere. so the clinical descriptions in the area of what we call mitochondrial diseases sort of primary mitochondrial diseases, ultimately every disease knocks

off the mitochondria and that's why we die. it forms the basis, otherwise one would be at a loss just screening people from mutations but not having a clue as to what the syndrome or the symptom is. so this is a very good unification.

all right. i'm going to tell you a very quick story to illustrate this. this is monument valley in arizona. the home of the western navajo. as the story here, american story of a poisoned land and people betray.

that's a long story we're not going to get into today but it has to do with things like open pit uranium mining, lack of support, malnutrition, all kinds of things. but this is a highly inbred population. in the next slide, thank you.

it's almost 20 years ago colleagues and i were visiting there because of youngsters like this who were incapacitated by a combination of neurological and metabolic and mainly liver diseases that sort of attracted me. so we studied some of these and

here's some of the families involved, particularly family two is the most accurate but it's hard to get a family history from these people but most of the folks affected were quite young. so this is a combination of neurologic problems and liver

problems. there's a lot of liver disease in this reservation, alcohol, hepatitis. very hard to dissect it all out. but the patients had impaired growth, motor and sensory neuropathy. that meant they couldn't walk

and they have sometimes no pain senses in their body. often cognitive impairments. muscle atrophy which was due to the neurologic problem. and due to loss of sensation in the cornea. frequently they couldn't see because they had scarring there.

and then they had this fatty liver which progressed to cirrhosis, even at the age of 15-16 years old. very very strange. and a metabolic abnormality which tended to lead to hypoglycemia and acidosis particularly if somebody had an

infection. it's not associated with great longevity. so we and a group of others, next slide, studied this thing extensively in the pregenomic era. we did all kinds of metabolic studies.

came to the conclusion that it was something wrong in some of the transporters that were present. well, it turns out that later in the 2006, this is the group at columbia that has done a great deal of work on genomics of mitochondrial primary diseases

and they described that this is caused by a mutation in mtv17 gene which has something to do with mitochondrial dna maintenance. and mitochondrial dna is having problems these going to be all sorts of say down stream effects like an oxidative

phosphorylation. in those days, we were looking way down at the end of the track. so this is an example of an incredible clinical description by various pediatricians and a very difficult area where it's difficult to get accurate

information. who got enough information that permitted some family studies. and then to recruit people to do what in those days was the state of the art sort of metabolic but ultimately led to the identification not just of this disease but as we'll hear more

bit later. of course the next thing is what does this gene do, and that's still a mystery. next slide. well, this is all familiar to you so i don't have to go over what the mitochondria does to make atp but that's going to

crop up again and again in the discussion. and this is really to introduce jennifer also because, so with this business of movement and something that now is widely accepted in cell biology but not so long ago, particularly prior to the discovery of green

fluorescent protein which jennifer was among the first to exploit to answer dynamic questions and then it expanded into probes that could be examined in living cells. so the theme of the whole thing, at least i think of her research is somewhat correctly stated by

galileo who said, and yet it moves. because he was talking about the moon. but nevertheless, within the cell. everything moves. and her -- long before said everything is flow nothing

remains the same. these are ideas but it took hundred of years to put them in the reality that you could see. we're very grateful to have both of you here and do you want to start. >> yes. >> lynne wolfe is the first

speaker. lynne is a nurse practicalister that you all know about called the undiagnosed disease program and she'll tell more about it. >> i yes work in the program we studied for five years the brain child of dr. bill -- it ended september 30th of 2012, and now

we sort of entered a new area which i won't discuss. this is paula and liz. liz happens to be a patient we saw in the undiagnosed diseases program, actually pretty close to its inception about three years ago i think, right. and she has a mitochondrial

deletion syndrome called kern-sayers syndrome. i'm not accused of being quiet usually. what i'm going to do is first just ask some questions from liz and her mom being diagnosed with a mitochondrial disease and living with a mitochondrial

disease and some of the things we are trying to do to diagnose other mitochondrial diseases on the clinical side. tell us when did you first notice any rent problems with liz. >> when elizabeth had her adenoids out she was three years

old. when she came out of the senior after anesthesia, she didn't come out of it too well. we brought her home and she was kind of like a rag doll much the next day they readmitted her because she had no muscle tone in her body.

it seemed to be after that episode her eating stopped, she stopped having difficulty eating. by the age of five she started to have cytosis with her eyes. >> what does that mean. >> toasts with thize means she had really big blue eyes, big

round eyes. her eyes started to droop a bit. they thought it was a neurological problem and my steam yeah gravis. these were different diseases they were sending us to hospitals check. we ended up at yale new haven

for i think six years, and after having numerous amounts of tests they came up with that she had an eating disorder and put a gi tube in her. and then we ended up after that, going to columbia because we're in the northeast so we have a lot of good hospitals around us.

at columbia we went into the mito twice. there was a letter here at the nih for undiagnosed programs. we sent in photos from birth to present at that time. you could see the progression with the eyes and weight and everything that happened with

her. after being here for one week, liz was diagnosed with kearn sayre syndrome. >> liz, do you want to add anything about your diagnosis for everybody? you're going to be quiet? >> do you want to talk about how

it is for you? >> tell us how is it now that you know your diagnosis. >> it's kind of hard for me because i can't really do that many activities with my friends. and do a lot of things. >> okay. >> do you want to ask anything

else? anybody else want to know anything? i'm going to talk a little bit more about kearn sayre and i can say a couple thing about lynn right now so you know this and you can pop in. so liz was being followed by an

eye doctor and so she had not only progressive lidx osis but she also had some changes in the back of her iso her optic never has gotten more atrophied, meaning it's wasted away. yes. >> i've got this one on so i don't need it, yes.

if i do, it's going to squeak so i won't do both. she also had retinitis pigmentx m entosis. she was followed by the endocrine service. the interesting thing here which is important for you all to know

is that she didn't see a neurologist or geneticist actually until she went to columbia twice and then came here and saw a number of different neurologists and geneticists. her pedestrian trix was the one person coordinating her care who

said all these eyes things are happening, all these growth things are happening and why is this not one thing. why can't this be one syndrome, and that was how she got referred to us. when her mom talks about the gi tube.

she has a gas trauma me tube which means she has a tube that goes into her stomach. she needs liquid food over night every night to maintain her health and weight because she can't eat or drink enough during the day because of the energy that she.

i'm going to ask you how you feel when your friends want you to go swimming or your bathing suit that your friends might see with your feeding tube. >> most of my friends know about it and they know you can probably see through. has it ever bothered you?

>> no. >> it bothered you. when you were younger you didn't want people to see your tubes. >> yes. >> we went through a little bit of on growth spell where we wanted to wear a bikini because we were afraid to show off our g

there are other things we're able to do. do you want to add anything else. >> i just wanted to add that the every day care for liz, when you have a mitochondrial patient is you have to constantly be like one step ahead of her because

things change really quickly like the heat intolerance and cold intolerance. we can bow going somewhere and she gets overheated. you can't like cool her right down it gets very dangerous. dehydration can happen within a couple hours.

she can be okay and all of a sudden she can be really dehydrated. as a parent, it's a lot of work, we always travel with water, we travel with snacks, we travel with clothes to put on, clothes to take off, ice packs in the summer.

she has a cooling vest to wear because she want to be outside with the kids. in order for her to be able to do that, she has to have this cooling vest which they've now made for mito patients. life is not, it's not like the other kids.

she can't play sports in schools. she's limited to how long she can stay there. the school allows her to take naps if she needs to during the day. it's a different life-style for these kids jierg i'll tell you

this just briefly and then i'll start my talk. in order for us to keep liz safe so she could come and share her story with you, she actually was flown in on sunday. so she had a full day of rest. she saw me in clinic yesterday morning early.

she had blood work done and then she went back to the children's inn for rest until earlier today, and she did take an afternoon nap for about an hour at about 1:00 so she would have enough energy to walk with me from building 10 to here and be able to share her story.

so her energy is very limited and doled out carefully. >> [indiscernible] >> that's a really good question. what we ended up doing for management of nutrition is not only addressing calories but we addressed her protein load.

so kearn sayre syndromes can have a number of associated witness. some of patients are -- like some of the patients develop parathyroid failure which she hasn't done yet which we're monitoring for. some patients develop diabetes

which we've been monitoring for and she sort is border line. we have her getting diabetic adult formula. it has about 11 of protein per can. so she gets about twice as much protein as a normal 14 year old might get if they're not like an

athlete. and she gets complex carb that are very slow. we go up and down but mom thought she was getting a little chunky and cut her from four cans to three cans plus her breathing all day. she went from 84 to 79 pounds in

just a week. so that fourth can becomes quite critical. so kearn sayre is actually not a specific began. -- is not a specific gene. kearn sayre is a -- the mitochondria has its own dna

which will be in my presentation so i'll just do that because it will make more sense if you see it. i'm not sure how to turn this one off. i don't want to like drop it. do you want to have it? you can stay there or you can go

on if you want. i was going to say. i will also say one of the things we were able to do importantly for liz and her family is the mitochondrial disease foundation is very very active. they have a four day meeting

every year with an overlap of the basic scientists and clinical sessions with a family session. and so liz and her mom and her dad have actually been two years, they have been very active and had the opportunity to meet with a lot of other

mitochondrial physicians around the country and genetic counselors and nurses and dieticians and they meet scientists that come 2509 meeting and a lot about mitochondrial disease management not juste but other people around the country.

so let me start this talk. and i heard there was a thing but i don't see it. so this is a stagnant healthy mitochondria by electron microscopy. and i have some pictures of abnormal ones but mine aren't moving.

i don't know, do you have movies of moving mitochondria? so i'm going to give you just some basic facts about mitochondrial disease in general because we think of these as rare disorders but they actually really are not. so a lot of people that work

with mitochondrial disease around the world have been trying to get a good handle on how heavy a disease load this is. and in 2000 there was a publication that found worldwide, we have a prevalence of about 11 and-a-half her

hundred thousand which means one in 8,500 of us will have a mitochondrial disease at some point in our life. in 2006, the incidence was one in 5,000. a very specific changes in oxidative phosphorylation, so those would be patients that

have documented electron transport chain defects. in 2008, there was an interesting study done by chinnary group in england. what they did is took the newborn screening cards from the entire united kingdom and did mitochondrial dna analysis.

and they found that one in 200 persons which translated to one in 10,000 of the adults in the united kingdom actually did carry a pathogenic mitochondrial dna mutation. the question is why are they not all manifesting disease. so we'll talk about that as this

moves on a little bit. so in the united states there's about 4 million children born each year and 4,000 of those will develop mitochondrial disease. but we also have about 50 million adults with either a primary or secondary

mitochondrial disease because as many of you probably know, we have mitochondrial failure in lots of things like cancer and infertility and insulin dependent diabetes, heart diseases, blindness, deafness. the list is quite extensive. we do also believe that

mitochondrial dysfunction ultimately is why we all age and die. so the functions of mitochondria that we all learn about from very early i think in high school is that you need your mitochondria is the powerhouse for your cells and that's where

your atp comes from. as it turns out the mitochondria has numerous other functions that are really critical to growth and development. and so i've listed them all here. and so this explains why when we look at our patients in the

clinic. we see lots of symptoms across all of the body systems. so consequences of dysfunction include decrease atp production which as you heard from liz and her mom, impact on how you can thermal regulate, how much activity you can have in a day,

how your body can utilize it's nutrients, and so what ends up happening is that decrease atp production becomes critical to a lot of the symptoms and the changes in 2k5eu8y things for these patient. there's increase in oxygen species which is felt to

contribute to ongoing mitochondrial damage and loss which can potentially make mitochondrial disease worse. liquid -- there's changes in the membrane potential for the electrical capacity of the cell membrane and apoptosis is programmed cell death.

so when the mitochondria are not healthy, our cells just don't think they should be hanging around jim and so those cells die off and then you have less mitochondria. here's the mitochondrial genome. i want to point out although this is kind of weak right here

is what's associated with kearn sayre syndrome -- opthalamic -- which are supposed to be a spectrum of exactly the same so it's just how much of the deletion do you have how big is your deletion, not manifest your so this is the mitochondrial dna.

it's very small but remember there are numerous mitochondrial dna in every mitochondria that are in our cells and there are numerals mitochondria inside all of our cells. so we have lots of copies of this particular mitochondrial dna, and so only of the dna will

have the deletion, and some of the dna will be what we call wild type. normal mitochondria. so the normal deletion in this dna is somewhere between two and-a-half to five mega bases. what ends up happening for liz she has 3.9 missing which takes

out nd4 this sub unit and part of a tp6. so she slices through like that and that explains her complex one, four and five function. the mitochondrial genetics is really complex, and i didn't put all of it in here but we can discuss it a little bit.

so mitochondria are inherited from our mothers. it's all in the eggs. there's very little sperm and where it is in the sperm is in the tail, the tail drops off and we inherited most of the mitochondrial dna from the mothers.

there's a weak genetic code to the mitochondrial dna that's different from our nuclear dna. there's something called replicative segregation which i'm going to show you some pictures of and some heteroplasma as well. there's a higher mutation rate

in the mitochondrial dna -- less repair mechanisms. our nuclear dna has lots of mechanisms to repair problems. but the mitochondrial dna doesn't have as many, and so if there's damage, a mutation that perpetuates. there seems to be a threshold

expression for phenotypes so you have to have a certain balance of bad mitochondria to wild type or normal might -- mitochondria before you have symptoms. that disease, i'll show you one example of a clinical syndrome that we do know how to look at the proportion of mutations dna

so this is a percent of abnormal mitochondrial dna to total mitochondrial dna and it can vary from cell to cell and also from tissue to tissue. and the percent of abnormal might coffin drug dna increases over time in normal aging. as somatic mitochondrial dna

occurs and do not get repaired. the set of -- may indicate age of onset of symptoms. so we see patients with mitochondrial disease that are very severe 2345 newborn and then we can see patients being diagnosed with mitochondrial disease in their 60's and 70's.

so this is replicative segregation, so unlike the nucleus. if you remember the nucleus, the nuclear dna will divide in half and you have equal amount of dna in each sister cell. but because we have if numerous mitochondria in every cell and

we have some that have disease and some that are normal. when the cell separates out you get a different dispercent of disease versus wild type and that perpetuates, and so you can't predict really well how the patient is going to represent so ma'am -- mom can

have a mix of disease mitochondrial and wild type and have no symptoms at all. she divides her cells and think about the owing and you can have those eggs or cells can have a certain percentage of disease versus healthy mitochondria. and then depending on that, she

can give to her offspring or even to a specific tissue. you might have some mitochondrial diseases that only impact muscle or only impact the gi tract. this could also be tissue specific. what could end up happening is

most fertilization -- a child that inherits more of the wild type or normal mitochondria will have less disease. the mitochondrial electron chain is called complexes. i'm not going to spend a ton of time on this but just to show you that these are multiple

complexes that make up multiple protein that make up each of these complexes. and so the function of each complex is not only dependent on how the unit works when it's together but also how some of these units are assembled. and because some of them are

actually regulated by mitochondrial dna and some by the nuclear dna, you can have mutations in either your mitochondrial dna or your nuclear dna impact on the maintenance and assembly of the complexes. or the function of the complex

once it's assembled. so even if it's assembled correctly, it might not give you the energy you want at the end of the day. that's a lot of mitochondrial symptoms and i kind of listed these. when we are seeing a patient in

clinic this is what we're looking for. we're looking for constitutional so general problems with growth which you probably notice but liz is under the third percentile for a 14 year old. she has short stature. cause text yeah is failure to

thrive it's unusual for anybody to need a tube feeding at the age of nine. so liz was diagnosed with failure to thrive at the age of nine and had a g tube put in before she was diagnosed with her mitochondrial disease. in hindsight we were able to put

that together. we see -- which is a very specific type of anemia you can pick up on a peripheral smear so you can see that on a slide. a lot of problems with the endocrine glands working. you can have lots of problems with nervous system including

early strokes and my game headaches which liz has had. and stroke-like episodes which liz has had. lee syndrome is actually a description of a brain degradation, neuro degeneration that was described and is seen in a lot of different types of

mitochondrial diseases. seizures, early onset dementia, balance problems, hearing loss and then eye problems which we actually talked about with liz. ataxia is an unsteady gait, loss of reflexes we heard when talking about you can have problems with cardio myopathy

which is an enlarged heart muscle. so it doesn't pump as normally as you would want it to pump. and you can have heart block or other arrhythmias which i think we mentioned. we mentioned to liz a year after we made the diagnosis of heart

block which is common in kearn sayre syndrome so she actually has a pacemaker in. easy fatigue we talked about, exercise intolerance, weakness in tone, muscle pain and cramps. ran dough my lyses is break down of your muscle and you get an el indicated chemical called pk or

cpk we measure in blood. that's not typical in kearn sayre but we see it in other ones. there's some kidney problems as well that you can see. and not every waish with a mitochondrial disease will have every single one of these

symptoms but these are the thing if you're in a clinic with a physician or nurse practitioner that look on the these types of patients, these are the things that are sort of red flagged for us as we're talking to the families and patients that make us think this is maybe

mitochondrial disease. the problem is there's incredible variability in presentation even if the same family so you can have children in the same family that will have slightly different symptoms because of the thing we already talked about.

because maybe they inherited a load of wild type versus disease mitochondria or maybe for some reason their disease mitochondria is primarily in muscle and somebody is having more gi symptoms. so it's really hard and we do need our genomics to help

clarify some of this. symptoms of mitochondrial disease is usually progressive and there's no cure currently. if anybody wants to work for a cure of mitochondrial disease, we would be very happy. and then correlation with molecular defects is variable

and will use mtv17 which has now been described for almost ten years. and we still have no idea what that protein does. and lots of newer mitochondria disorders where we found genes that we know we can localize to some part of the mitochondria

but we don't know what the proteins do. so there's 400 currently published clinical syndromes. they fall into these general groups but i won't pretend to tell you this isn't an inclusive list because it chances pretty quickly.

the older disorders are recognizable mitochondrial syndromes from dna point mutations that were first starting to be described in the late 50's and early 60's which kearn sayre was described in 1959. so they have these very nice

acronyms. so -- they sort of roll off your tongue but what you need to know behind there is -- is a chronic epilepsy with lactic acidosis -- like syndromes. aren't you glad you don't say that all the time. and -- are retinitis pigment owe

saw. the deletions and rearrangement includes the -- anemia. and then we have a number of mitochondrial diseases that are related to nuclear dna. so we have an autosomal -- atrophy. there's specific type of --

there are codependent functions so co-q which many of you guys probably see now very common in hair lotions and face creams. but everybody forgets it's really critical to mitochondrial function and it's a normal chemical in our bodies. electron transport change

efficient sees can be single or multiple, and complex one is the most isolated complex one is the most common across all ages. but frequently more than one electron transport chain complexity is involved. then we have a number of mitochondrial depletion

syndromes which is where the mpv17 gene sits. there's now numerous genes that are associated with the syndromes. and so what happens there is for whatever reason those jeans impact on either mitochondrial dna maintenance or the

mitochondrial dna bio genesis. so in our mitochondria, your mitochondrial dna is not being replaced or not maintained. those mitochondria die and then you end up with a mitochondrial depletion syndrome which are usually more severe than some of these other point mutations.

because you literally run out of mitochondria in your cells. i worked with a neurologist once that told a family imagine a chocolate chip cookie, all the chocolate chips are your mitochondria and it eats those and the cookie just crumbles. there are carrier proteins and

multiple carrier proteins -- is now probably close to 20 genes. we still don't know what all those proteins are doing. we have associated proteins with the mitochondria that cause mitochondrial diseases and then we have secondary defects i talked about like parkinson's

and alzheimer's and myopathy. there's a threshold effect and you're starting to see these are abnormal mitochondria with crystalline inclusion and these are misshapen mitochondria. so some tissues require more energy than others and so those are the symptoms that are going

to show symptoms first. and so when you think about those you can use liz as our example. the nervous system requires tons of energy and the eye is part of the system and so is hearing. so you have lots of brain problems, lots of eye problems,

lots of hearing problems. the peripheral nervous system, what gives you balance in your ability to walk, that also is high energy. so muscle, so your skeletal muscle, we have to stand with our skeletal muscle, we have to move with our skeletal muscle so

that is another high energy tissue. the heart muscle, and then remember that you also have smooth muscle in your gi tract and your breathing. some patients with mitochondrial disease have lots of problems too even though i didn't

necessarily mention that. and then the endocrine gland is very important to normal growth and development are also high energy so we see lots of developmental and growth issues. and then our kidneys. so then lifer and other things. but these, this is why you see

the symptoms that you see because these are the tissues that need the most energy to function properly. so in the narc syndrome we know in a mitochondrial dna mutation this 39g the clinical phenotype were buried by the mutant load. how much disease mitochondrial

you have in comparison to your and so what you can see is if you have zero to about -- that can be variable in some patients, you will be considered normal you won't manifest but somewhere if you carry 60-75 percent ocean of this mitochondrial mutation you might

have retinitis pig moan toe saw and that will be identified with your doctor. night vision problem is the most common thing first. but if you have 75-90% of a mutant load of this particular mutation. you have a full blown narc

syndrome which is a late onset syndrome that you usually see in your 20's to 30's. and then you might, from 90 to 100%, you have a full blown infantile syndrome which is fatal before the age of two. so this is one mitochondrial mutation that mutant load has

been really well characterized for. we don't have this type of data for a lot of the other ones but it might be nice when we're looking at spectrum of disease over time. the mitochondrial deletion syndrome -- peersons and kearn

sayre that we talked about. the classic diagnostic criteria which were identified actually by an ophthalmologist and pathologist, not by a neurologist or a genetics person. but 1959. so an optimal gist naysed they

develop paralysis of the eye movement. i didn't do it with liz but that's part of the rest of her syndrome and we were looking at clinic yesterday. so she actually has problems looking up a looking down and looking sideways.

and that is actually getting worse over time. she has retinitis pigmentosa -- some type of neuromuscular include degeneration. this is the classic criteria. over time to what's been associated with kearn sayre is endocrine kidney problems.

we know about the deletion i talked to you about this already. it can be autosomal recessive nuclear dna mutations can also cause kearn sayre although the most common thing is that it's sporadic. it just shows up.

and we know that is in liz's case because you would expect a mitochondrial dna problem to come from mom, right. we tested mom and mom doesn't visit so if mom doesn't have it -- we can't test a woman's eggs -- smatally in her body cells mom does not have this

deletion. liz has it. liz has two healthy brothers that don't have it. so these are some old pictures of liz. with her droopy eyes close up and her inability to really look up one of the things we noticed

when we first saw liz in order to have her look up she had adapted to doing this. you would ask her to look up. instead of being able to move her eyes up she would move her whole head up so her eyes went up, right. but really if you hold her head

still she really now, she can't even get this much. now we're not really seeing it at all. and so this is actually, this is before you had your eyelid surgery and you didn't even talk about that. she's actually had eye lift

senior because her tosis got so bad she was unable to read for school. rent thigh tice pigmentosa is seen as you loose -- doctors at the eye institute took these pictures for us. this is her optic nerve and you can tell it's smudging at the

edges. so that's with the atrophy. now to make life harder, there has to be cross talk between the nuclear and the mitochondrial genome which i had put up before. this is the cause for a lot of of the depletion syndromes plus

minus deletions. so there's actually a reduction in the mitochondrial dna which i sort of already mentioned. this group of genes is really growing and this also can be dominant recessive or sporadic. so we sort of have already talked about this.

so here's the clinical dilemma. so the clinical dilemma is underlined as in potential. so we have significant limitations in diagnosing these disorders because what we all learn early on is to look for lactic acidosis. but lactic acidosis occurs in a

third of the patients and most frequently in the younger patients but not in adult patients. and so we have to look for other things. is there anemia meaning not enough red cells or pan cytopenia meaning not enough of

any type of cells, white cells, platelets and red cells. are there some elevated liver enzymes as mpd17 you'll have severe liver disease. we can see that in a couple of the other mitochondrial disease these are not specific things. you can tell already because you

might have anemia because you don't eat well or whatever. we have low blood sugar. in mitochondrial disease it tends to be what we call post prandial meaning after a meal. elevated ck we talked about uric acid. so all of these things we see

sometimes but not all the time. and so we have very bad biomarkers really in the thing that we can get to easily like blood and urine. liz does not have lactic acid in her blood bewe've looked at cerebral spring flood and it runs very high.

that's probably why she still has episodes and migraine headaches and some other things we're trying to manage. there are specific enzyme so if you do enzymes, if you test skin you may or may not find enzyme deficiency. the tissue with most disease

like liver or muscle sometimes you'll get a better indicator of mitochondrial disease but heart biopsis are not easy to do. and you do sometimes have heart issue you want to look at. and we don't usually go to do brain biopsies on patients to diagnose a mitochondrial

if those are the tissues that have the most symptoms you have a limitation. the mitochondrial depletion syndrome or mitochondrial depletion in muscle content can be used as potential biomarkers but only a few places around the country do those and it's not

seen in every time of and it can be seen in other types of diseases so again not super specific. and molecular confirmation right now we know there are two genomes so you have to look at my chondral dna and nuclear dna and that's difficult.

so i talked about limitations and here's by numbers. and treatment. we sort of already talked about with liz there's lots of drug induced. there's a whole book you can get available on-line for those things to avoid.

and then basically let's mitochondrial cocktail which use to include a lot of things but now pretty much yew big null which is the water soluble form of co-q and carnitine and creatinine -- have done good studies with -- in 2007 and 10. and then i just did a big review

of the state of mitochondrial supplement research if anybody wants to look at that. and i think we should hold questions and let jennifer talk. so in summary for any of you that want to do some research, i think there's some definitions that need to be clarified.

we have very few natural history we have difficult diagnostic strategies because we don't have good markers and other diagnostic tests. and we have treatments that are really heavily focused on oxidative stress management but not a lot of other things.

and certainly no cures that would be cassidy. that's my baby. [applause] thank you very much. we have time for some questions and perhaps anyone who wants to ask liz. >> i think i just heard about

gene therapy in utero for let's actually a number of genes [indiscernible] >> so there are a number of those and i didn't put them on the slides because it's preliminary. the whole prenatal diagnostic thing is a whole other nightmare

and i have those slides out. if anybody wants to know about prenatal testing i can discuss that at a different time. >> is the distribution of the mitochondria from the mother to daughter cells is controlled or is random. >> it's completely random that's

the problem. completely random. unless you figure out a way to control it. >> what is the force of disease for liz. >> liz has the mitochondrial deletion so she has a chunk of her mitochondrial dna in every

cell or body missing lots of chunks out of lots of those dna so we did understand her mechanism of disease well. >> so how about some mri -- >> so her mri of her brain does have some abnormalities that we would expect, some white matter changes.

but chemically it was the bigger thing. so chemically she has high lactic acid in her spinal fluid and she has cerebral -- to manage those but that doesn't cure it. that just controls it. and her heart, you are heck owe

cardiogram has been normal but her ekg did develop -- she has a heart pacemaker in now. >> is it -- >> yes, it is. >> thank you. >> i defer to the cardiologist who said -- is the only way to go these days.

>> what happens when patients with mitochondrial disease have some acquired infection or immune disease how do they respond. >> you can imagine an infection or trauma increases our body's need for energy and they can't really mount energy on a normal

basis as you can tell by liz. if you have inadequate energy to start with, and mom didn't actually discuss this but when liz gets sick, she is sick, circumstance than her brothers would be or other kids her age and she stays sicker for weeks. it takes her a month to recover

from strep throat right. that's what we see for other types of mitochondrial disease as well. it really impacts on your activity going to school, going to work is really hard. >> so the question was do we know the mutant load for liz

and the answer's no. we don't know. so we did some heteroplasma studies only in blood and that was about 40% but that doesn't tell us how much mutant load might be in her eye or in her muscle or in her heart, and so it's kind of hard to tell.

we know there's tissue variability. >> you mention yew big null as a complex one and two treatment. is that just to make up for lack of normal yew big null or is there some curative effect. >> it's not curative and it's not specific to complex one or

two so. that diagram i sort of rushed through a little bit so so that is the normal electron carrier between complex one and complex three and complex 2 and 3. when you hear the chain is numbered one, two, three, four five you think it goes in that

order but one and two really don't even complete. so it basically goes one to three and two to three and yew big null's the electron carrier but yew big null in general we use as a reactive ox judgment species mocked basically for loss of different types of

mitochondrial diseases so it's not curative and it's not really >> i think we should move on maybe. do you want to make a last comment? do you have anything you'd like to say. >> yes, sure.

it's hard for me to really keep up with my friends because they have more energy than me. and i don't have enough to keep up with them. >> we want to thank you very very much for being here. [applause] >> jennifer is the head of

the -- chief of the section on organelle biology at nichd. >> it's sobering to talk after what we call the organelles of this mitochondria can do. in the next 30 minutes is to give you a perspective on what we know in terms of the cell biology of might condraw.

by getting greater insight into the dynamics of this organelle and how it's behaving under different conditions, stress or starvation to get a better handle what's going on when you have these diseases like what liz had or has. so mitochondria are unusual or i

would say remarkable organelles within cells because they really represent an -- i think if we get these lights down it's going to really help you see some movies and everything. this is a movie of a cell that's been transacted with mitochondrial plus protein that

targets to mitochondria. you can see that the cell is just chalk full of these organelles that we call they look like little bacteria that are swarming around within and the reason why they look like that is because that's in fact how they evolved, how they

coevolved with the -- system. so the idea is mitochondria originated -- that was engulfed by an ancient archaic cell and that together they acquired a hosts of new characteristics that essentially created what we now, what we call the yew cariotic -- trace an origin

that's over two billion years separated from this yew cariotic. so a lot of evolutionary biologists now believe that what really defines the eucaryotic -- and together they acquire, they both essentially created a symbiotic relationship that

allows the complex functions of this in the cell. the mitochondrial functions must be deeply integrated with the activities of the cytoplasm in the nucleus of the eucaryotic cells. otherwise these little proto bacteria would have been at some

point sort of lost from cells. but every single eucaryotic cell that exists on this planet has mitochondria or mitochondrial genes associated with them. this organize envelope is deeply integrated and comes with this activity with the host, with its host.

so what are some of those, that integration. well you heard a subset of all the things mitochondria can do which includes iron sulfur cluster formation apoptosis, calcium regulations, team biogenesis. this chart right here gives you

the cell -- transport chain where mitochondria can produce in a very efficient way atp. but in fact, when cells are exposed to glucose, lots of glucose and are not starved or stressed in any condition, the carbon chains that come through the mitochondria and moved

through this cycle are by and large used in anabolic processes to build for instance lipids or amino acids or nucleotides. a lot of the energy from glucose on sugars that come into the cell are being used by mitochondria to actually form, create synthetic components of

lipid amino acids and nucleotides. it's only under special conditions that i'm going to be showing in this talk where cells really start shifting up to fundamentally on this phosphorylation function of this pca site.

so mitochondria are really, you can understand how they are fundamentally imbedded in terms of all of the biosynthetic and metabolic pathways within the now what's intriguing about mitochondria is that they themselves can undergo a fusion site.

they don't just sit around as 200 little sort of bacterial-like structures that are moving around the cell like i showed in that movie. they are capable of actually fusing as well as under going fusion. this is regulated by genes that

drive fusion and this includes one two and o for one and gene products that drive fusion. this is a dynamic related protein which i'll be talking about these proteins that are regulating this fusion state. now one of the thing that we know is that when mitochondria

are highly fused, essentially they are more likely to release cytochrome c and initiate the apoptotic response that leads to cell death. with mitochondria highly fused cells seem to be protected from this process of cytochrome c release and apoptotic stimuli.

the cell is clearly interested in regulating when to have cells, mitochondria fused first fragments. well a post doc in my lab by the name of mitchell was intrigued enough to address the question of what's the state of different stages do mitochondria

change their chain in any particular way. is this important for the cells to go through items cell cycle. what do i mean by cell cycle. cells essentially have two really separate states. they have a state where they're essentially dividing, separating

and that's my tests and they have a state where they're duplicating their nuclear genome. this is called s state. and these intermediate stages which are called g1 and g2 are gap phases where the cell is neither dividing nor duplicating

its dna. it's essentially just hanging out so to speak. >> what is the cell line. >> this particular cell line is nrk normal activity cell line that we've done this in a variety of different cell lines. the up shot from what -- found

is at that time mitochondria which are shown in red here at each of these stages of cell cycle undergo a dramatic change in their morphology. specifically during mitosis, mitochondria frag into small individual units, about two to 300 units.

that we believe is important for the cell to be able to partition mitochondria efficiently as the cell divides in two. at the other extreme, this s phase mitochondria becomes highly tuballated and interconnected and in fact we've shown they essentially fuse into

an almost single hyper fused into one interconnected network. and in g1 and g2, they essentially are intermediate between this highly fused state which occurs right at the g1s bumped -- boundary and highly fragmented state of mitosis.

demonstrate how dramatic had change is -- here's a cell showing mitochondria in red. that is in g1s and you can see this mitochondria essentially fused almost entirely together. 9 0% of mitochondria matt -- math is a single structure. there's a dramatic regulatory

change in terms of fusion dynamic as the cell is proposing itself to replicate its nuclear genome in s phase. well, pastory went on to determine is there anything special about this highly to be lated mitochondria. she observed at g1s.

remarkably what she found was not only the outer membrane to the mitochondrial fuse at this stage of the cell cycle but the matrix which is the internal reach here surrounded by this inner membrane is also continuous throughout this whole fused mess.

there's increase membrane potential associated with these inner membranes suggesting that the electron transporting is more active it's producing more atp. and consistent with that, we can absolutely see increased atp generated capacity of these

organelles. what this suggests is mitochondria are under going a cell cycle pennant change in their morphology is changing the atp and the organelles right at the critical stage of g1s. the immediate question that arises is this change in

mitochondrial -- we treated cells with a drug -- that causes mitochondria to, and when we treat the cells, what we find is cells cannot go into s. what we're looking at here is a s phase marker pc and a which labels -- the dna replicative -- you can see the normal untreated

cells, if you start imaging them in light g1 within four hours they're going into s phase with this marker. by contrast, if we take, we do parallel, treat the cells, you can see they never go into this s phase. so ten hours later the nucleus

is still showing no sign of any type of replication. and this is just a different type of experiment where you're looking at the incorporation into the dna to determine dna replication. if we add these we do not get the rdu incorporation contrast

to control cells which is about three or four hours after intubation starting at mg0. so what we're suggesting is that the transition of the mitochondria from this highly fragmented of this dynamic tubulated state at g1s is critical for cells to go into s

phase. it's almost it's a type of a check point. and consistent with that we see that p53 is absolutely required for this. you need increased p53 in order to get this transition. and we can also receive

correlation -- which is the s phase cycling during this process. so we can actually initiate a g1s check point by essentially interfering with this process. well if this highly fused state is important, first of all to s phase, can we induce cells to go

into s phase. simply by manipulating the mitochondrial morphology. one way to do that is to interfere with fission machinery to be responsible for driving highly fused mitochondria into this fragmented form. you can do that by either

expressing a mutant form of drp1 over expressing it or by adding a drug that interferes with the activity of drp1 called mdd1. and so what we decided, if we added mbp1 in cells that essentially these are cells that are in g1, we add mtp1, what you see is within four hours we

start accumulating cyclin e which is the cyclin that is responsible for progression. as you can see the mitochondria become highly fused. so this suggested that we're actually pushing the cells into the cell cycle, into s phase by causing mitochondria to become

highly fused. so in order to more rigorously test this, what we did was took cells that has been pushed out of the cell cycle by serum starvation and into this phase that's called g0. they are no longer cycling these cells because they don't have

serum. and we ask, could we take these cells out of g0. and drive them back into cell cycle. by manipulating morphology -- looked for brdu incorporation which indicates replicating dna. here is the result of this

experiment. this shows dna in blue and brdu staining in red. g zero serum starved cells you can see none of the nuclei are essentially replicating the whereas by contrast, after three hours of adding this drug which causes mitochondria to become

highly fused, you now see that a large fraction of these nuclei in these cells are replicating their dna. indicating that simply by causing mitochondria, driving mitochondria to become highly fused can force these cells into s phase, can drive them through

the cell cycle. so this is pretty exciting when we made this observation. we were really excited because we started thinking that maybe this is somehow connected to the decision by cells to differentiate. mitochondria is playing a role

the idea is diagramed here. these cells proliferate and then at some point in the life cycle of these proliferating cells, they decide to stop dividing and at that point they go to g0. and so what we wanted to know was whether we could impact that decision of cell to

differentiate versus continue to proliferate during development. by manipulating mitochondrial structure, mitochondrial fusion state. and so to test this, we used the oocyte as a model system because it's very easy to knock into these fallen off cells that are

essentially an epithelial cell layer that surrounds the oocytes and these nerve cells. and can knock in mutation of arp1 which means these cells will not have fission machinery and mitochondrial become highly fused. or alternatively we can silence

a -- which is responsible for fusing mitochondria. the results is the mitochondria will become fragmented. and so i ask, if we introduce these mutants -- can we alter the fate of the cells during and the answer is yes. it's incredibly exciting.

here is, this is a normal egg chamber where you can see the cells are just a single epithelial layer. these follicle cells are blue like the nuclei. if we express a mal -- so the mitochondria now are going to be highly fused together because

you don't have fission. what you now see is the cells proliferate dramatically. and so you just have huge amass of cells that are continually dividing under these conditions. you also, if you knock it into areas of the egg chamber where the cells are differentiating,

you lose the ability to make the stalk cells because the cells are proliferating. they're not dividing any longer. and all we've done is just changed the morphology of mitochondria so that they're more highly fused. now we can do the opposite

we can knock down -- making the mitochondria highly fragmented. and under these conditions, if we look at a differentiation marker, we can see that mitochondria are actually differentiating earlier and are prematuring differentiating under these conditions.

so what we've been able to illustrate in this follicle cell model system in the fly is that morphology, driving the mitochondria into a fragmented or fused state, we can shift the cell state of that epithelial layer to one where the cells are prematurely differentiating or

one where the cells are proliferating as they should. so this suggests a really important role of mitochondria and cell fate determination. we think that this is potentially playing itself out during development in a big way in a lot of different tissues.

if you're interested in this, this paper has a lot more packed into it in terms of how these, how fragmented mitochondria actually talk to notched signaling pathways -- i don't have time to go into that. we think a part of these controlled pathways is the

physiological state of the so as i mentioned, we think mitochondrial state regulates sell cycle progression and cell differentiation. well do other cellular states require highlyused mitochondria or can they be impacted or do they need highly

fused mitochondria. and for this -- in my lab made the observation when she starved cells, she found that mitochondria became highly tubulated and fused together. cells in g1 or g2 the mitochondria are constantly moving around under going

incision infusion. when you starve these cells. we don't have serum and we have very low glucose. the mitochondria now fused into this very highly integrated network. so that led us to start thinking well maybe there's something

going on with this network that is helping the cell survive starvation. so let me just emphasize what's happening under nutrient deprivation. what the data from labs is now suggesting is that the fission machinery is actually being

inactive under starvation conditions. and so are as a result mitochondria comes come much more highly fused together and you get this phenotype i'm talking about. now what does this phenotype do? i'm going to shift to yeast

where arnold in the lab has been doing some pretty exciting stuff looking at glucose starvation and what it does to mitochondria in weeks. and so if you shift these from a 2% glucose diet to a .4% glucose diet, what you see is mitochondria actually becomes a

mass of mitochondria increases dramatically and the mitochondria becomes highly so again starvation is causing mitochondria to actually grow and become and increase their mass, increase their highly fused characteristic. this is just showing that you

can see increased transcriptions of mitochondrial infusion genes under glucose in yeast. what are the tubulated mitochondria doing under starvist. when they get starved that triggers m kinase activity which inhibits mtor which controls

growth and then start interfering with this mitochondrial fusion machinery and ultimately you get mitochondria becoming highly tubulated. well what does that high tubulation do. one thing it does is it seems to

boost cellular respiration and that's illustrated here with.4% glucose you can see increased oxygen flux for unit cell. so having highly tubulated mitochondrial system seems to really boost your ability to use oxygen, flux oxygen up. and you need this mitochondrial

fusion to survive low glucose. if we prevent these mitochondrial from becoming highly tubulated under starvation conditions you can see the cells die and this is just we're inhibiting with the lost mitochondrial fission and you can see the cells die under

4% glucose unlike normal cells. well, if you look at what's going on under these conditions with glucose starvation, you can see that the mitochondria, these are in red, are highly tubulated and if we look at an auto phagic marker, you can see the mitochondria are essentially

protected from mito phagey destroyed by the self eating mechanism called mito phagey. this is where we interfered with mitochondrial fusion after knocking it down -- mitochondria now fragmented. you can see these red little fragments of mitochondria and

all of these mitochondria are now being eaten in a process called mitophagey. you can pretty much wipe out your mitochondria under these essentially prevent mitochondria from being tubulated under certain conditions. so tubulated mitochondria under

starvation conditions which is driven by the cell energy sensor system -- it's allowing the mitochondria to actually survive. and as we also found that remarkably, the to be lated mitochondria is driving non-selected -- we notice

because we've been looking at -- this is an auto phagic marketer. when you look at it as cells are starved. you can see there's a dramatic increase in your total autophagy cells under certain conditions. when you look where these cells come from a they come off the

surface of mitochondria. to the left is mito tracker and in green is an autophagic marker. you can see as auto package so manies form they're forming off the mitochondria. what this is suggesting is that three things under starvation.

because the mitochondria can produce atp more efficiently so you shift to oxidated phosphorylation as your major energy supplier. but at the same time you're protected from mitophagey. tubulated mitochondria do not release -- efficiently and the

tubulated mitochondria we believe drive a non-selected auto phagic process which ultimately releases pre-- ultimately under these acute starvation conditions, we can see the cell adapt. so you can get a feedback mechanism here where you

actually slow the mitochondrial are essentially driving the show under the starvation conditions and the cell's pretty happy for quite a long time. well how can this cell be happy for quite a long time when it's being starved? well blood glucose and

glycolysis is shut down under the conditions i'm talking about. but the cell is loaded with lipid -- these are fat globules that have accumulated during glycolysis. and what's going on under sedation is that the cell is

shifting its metabolism so it can now start breaking down these lipid droplets, taking these fatty acids, feeding them into the mitochondria and then driving the tca cycle so that you create this much more efficient atp release production.

so the tubulated mitochondria we believe that are induced under starvation conditions are playing a multi-pronged role in self survival. in addition to trying mito phagy for the cells to reboost itself to make thing it needs under starvation it's protecting the

cell from apoptosis as well as mito phagy -- respiratory mechanism. so with that, i want to just end by thanking the people in my lab who has been really driving all of this work. i want to thank -- who really initiated all of the

mitochondria work in my lab. she now has a great job at the university of alabama. and the people from my lab carrying on that work includes kelly grammable who did the work -- initially observing the mitochondrial starvation and arnold -- who is doing the

work -- i want to thank sara cohen whose been looking at the lipid droplet connection and dale haley whose done all of the work related to mitochondria and mito phagy that i talked about. we collaborate with a variety of different people at the university of florida and nih in

areas we actually have some really interesting data related to the role of draw and cell polarity, the generation of cell polarity. so with that, i'll end and thank you for your attention. and we can have some questions if you want.

>> thank you very much, jennifer. jeff, can you put the light on. thank you. go ahead. >> so [indiscernible] structural changes that are happening [indiscernible] proteins or just [indiscernible] in each

>> we think it's a combination of both the fusion machinery being activated but also inhibition of fission machinery. so the machinery that normally causes mitochondria to break apart we think is being inhibited. and so the cells, the

mitochondria don't break apart and they are more efficiently fusing. and so you get this shift, this entire shift of the mitochondria from this sort of dynamic fission fusion organelle to one that's more predomintly fused. >> looking at the influx you

have the glucose and the glutamine, so u think if they are used as a nutrient, it also could be used in the patient with mitochondrial disease to get rapid -- so that's a really cool i was thinking about that myself while i was hearing about all of

this. so in terms of liz, what's going on with liz. i don't really know. this is the first time i've heard anything about her syndrome. but it sounds like she can't, she cannot do this --

she's got a real problem in utilizing this -- >> well she's doing glycol sist. yes got her gi tract. she's living off of food that's essentially driving pathway. glie so as long as she's got sugars that she's being fed and

protein, they're driving this pathway that can push the cycle at least to the extent where you get citrate to make lipids. amino acids. not clear how, she's clearly not getting effective oxidative phosphorylation. >> [indiscernible]

if you put too much sugar into the system you actually make their lactic acidosis work. that's why we [indiscernible] that's really good because we get too much glucose in here she's just going like this. so you fill in these components that mitochondria normally would

be making, that she's not making very well. the treatment of mitochondrial diseases one of the really exciting research areas is the use of exercise. and the reason tt we promote endurance training is that it promotes wild type genesis.

i'm wondering whether or not not so much from the perspective of stopping starvation as a management for a patient but whether or not pushing the fusion and cell replication would increase their mitochondrial biogenesis at all. and that may tually be a great

cure for a number of the mitochondrial diseases because some of the newer drugs and exercise therapy and some of the other thing we're now looking for treatment really are pushing and focused on mitocndrial >> have you tried fasting at all.

so calorie restriction has long been utilized. the problem is that in a healthy individual, calorie starvation and in mice and rats promotes longevity but if we arve liz, yes, so in our truly effective mitochondrial disease patient, starvation does not --

>> with liz too i don't think exercise's going to do -- she's in a different category. >> she is because she took out three complexes she's severely impaed, s. >> jennifer, what happens to mitochondrial dna during fusion? >> that's a good question.

we don't really know. people are trying to look at that. it's probably more interesting what happens during fission when mitochondria break apart. and right now there's a lot of people who are looking at this. i think there are some papers

coming out but the thinking is that the site where where the division is occurring is t a site where dna is replicating or has replicated. because every fragment of mitochondrial has dna associated with it. so there's a very good coupling

between when a mitochondria breaks into two and the dna goes >> the proportion of normal and d normal. >> they're probably mixing in, >> i'm sorry. the proportion of normal and abnormal mitochondria -- what happened, it's conceivable that

what happens during fission and fusion, does that representation still represented whatever it is 50% -- 20%. >> is there perhaps -- >> -- lots of dna associated with it hen they fuse together. and the issue is, is there some way that you could, can the sell

recognize mitochondria that have some sort of perturbed damaged dna and selectively get rid of it by mito phagy. that's an interesting possibility that so far nobody's clear on that. >> jennifer. >> i wonder if you can

reconcile, if i understand correctly, if you induce artificially fusion and you have this long tubular mitochondria, the cell is driven to division. yet under starvation you're basically getting the same tubular function -- how do you reconcile that.

>> because in one situation, the cell is well fed. when the cell is liquiding, the cell is under a well fed condition and there's serum. under the conditions of starvation there's no starvation and no glucose. so we're seeing a change in

morphology at each case at least at the level i talked to you now exactly whether they're identical in terms of whether the transport flexes are in a into complex or how they are arranged, we don't know. we have to get to another level of magnification so to speak to

understand that. but clearly, they're both, the highly tubulated has a different function in a cl that's starved versus a cell that's well fed. and you know, under serum, driven under serum. >> and you can't detect any

difference between those two states. >> i don't think we've looked enough -- looking at the fusion mobility, how connected. >> -- gene distributed in the body. how is it distributed. >> in here?

>> it's somewhere in this matrix. this past year there's been an imaging paper from herald hess where they look at matrix numbers and nukoids. you don't see anything just a big blob of dna sitting somewhere.

so far we haven't been able to relate it to anything in yes? >> when the mitochondria fuse the membrane potential goes up. i was wondering, have you actually measured that because if it goes much above 200, your mitochondria become leaking and

actually your production of atp becomes less efficient. and the follow up to that, do you know what happens to the -- when you fuse where you actually have atp [indiscernible] >> so pastory does these measurements using -- and did ratio analysis to mito -- to

look at the increase at s phase relative to the different other phases. and it goes up two or three folds. it's really different than if she hyper polarizes the membrane where it goes up 10 or 20 fold. we don't think it's causing any

kind of leaking or the kind of laking you would get under a hyper polarization scenario. but definitely we've had quantitative data that the membrane potential is going up by at least two or three fold. >> we do have an ips, though. >> would atp help for the

patient, if you give the atp to the patient -- >> just give atp to a patient? i don't think so. >> second question is how do mitochondria [indiscernible] how do you come the number. >> [indiscernible] we have to take a sample of all the other

tissues and actually ask the same test done [indiscernible] >> [indiscernible] -- fusion data in relation to starvation -- showing that in case of a starvation you get more fusion, am i direct. >> you definitely get more fusion that's the only way you

can get more tubulated. >> but i thought you were also interfering with the fusion and were showing fused ones. >> right. >> against mitosis. >> that's a good point. so one possibility is that all that's happening is you're

blocking fission. >> but we've also seen using fusion, that fusion genes are important as well to make this process efficient. >> but have you shown that in case of a starvation under electromicroscopy you get more fused than mitochondria or any

other method, have you shown only the starvation, no other manipulation. >> the mitochondria shifts from being fragmented to being much more highly fused, and we can quantify that under starvation conditions definitely. >> can i ask a quick question

while i'm walking down here. so if the problem in the mitochondrial diseases is basically a reduction in mitochondrial number or function. rather than something that the quote bad mitochondria are doing to inhibit the good

it's a depletion. is there any role in enhancing mitochondria bio genesis through things like the -- so you have nice and all with knock down of these models. has that approach been considered? and interestingly enough those

are exactly the [indiscernible] yes though things are actually being studied [indiscernible] >> i was curious with your really interesting data on the role of the mitochondria and sell cycle progression, we already know they play such an important role in metabolism.

i was curious about whether and gwen mentioned it's not as sophisticated as genomic dna whether an accumulation of mitochondrial mutations plays a role in carcinogenesis. >> i would probably think so, yes, absolutely. >> i think the perfect example

is p53. so p53 in addition to its role in self cycle control is also regulating a lot of mitochondrial genes. and so we think that that's very much connected, we think actually cells -- sort of making the decision do we have ough

energy to actually go through s so that we can efficiently replicate the genome. and the cell makes that decision based on a number of things that you he enough nutrient, what's its metabolic state, etcetera. and we think that mitochondria is key for that.

so if the cell doesn't have enough energy, the cell goes into a g1ss -- i should emphasize that when we knock down p53, we were unable to get to see the mitochondrial induced cell cycle block. remember i said we could fragment draw and cells could

not go through s phase. well they do go thugh a phase if we don't have p53. >> so it seems to be down stream. >> exactly. they're definitely talking to each other. >> i had a quick question about

your motto in the slide. so you induce proliferation by inhibiting the fission machinery but in the normal cell cycle you showed that fission was necessary for cell division and i was wondering if you understood how that work. so it's, we're seeing this

particular phenotype where we're inducing proliferation causing the mitochondria to become -- in this particular area of the follicle cells where they're actually, those cells are receiving growth factor stimuli from the oocytes. so the oocyte releases gerken

and that's what triggers mitochondria to actually undergo fragmentation. and that is a trigger to differentiate those cells normally. and if we interfere with that, the cells don't differentiate, they just keep proliferating.

well, i want to thank both of you very very much on behalf of all of us.

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