Liver Metabolism with Gerald Shulman

Transcript

• 00:16Good afternoon, welcome back.
• 00:18This session is being recorded. Thank you.
• 00:24So our next speaker is going
• 00:25to be Gerald Schulman.
• 00:26He's professor of medicine as
• 00:28well as professor of cellular
• 00:30and molecular Physiology.
• 00:31Who's going to talk to us
• 00:33about the metabolism, Jerry?
• 00:40OK Rob, thank you.
• 00:42So I was asked to speak
• 00:44about liver metabolism.
• 00:46Here are my disclosures.
• 00:48I will be speaking about liver targeted
• 00:51mitochondrial coupling agents.
• 00:53This is a Yale patent.
• 00:54I'm an inventor and I'm
• 00:57a scientific co-founder,
• 00:58founder of a company that is
• 01:00promoting liver targeted uncoupling
• 01:02for treatment of Nathan and Ash.
• 01:03So I wanted to start with metabolic syndrome.
• 01:06This is something that's affecting.
• 01:07More than one in three Americans,
• 01:09this is from Jerry Reubens
• 01:11Banting Lecture 1988.
• 01:13It's a constellation of things
• 01:15associated with insulin resistance,
• 01:16of course, diabetes,
• 01:17but it's also leads to atherosclerosis,
• 01:20high triglycerides,
• 01:21alterations, and inflammation.
• 01:24Uric acid PCOS, hypertension,
• 01:27and moving to 2021.
• 01:30We can add not only cancer,
• 01:34but not alcoholic fatty
• 01:36liver disease and Nash.
• 01:38And what I'm going to do is try to
• 01:41show you how insulin resistance is
• 01:44actually promoting these abnormalities.
• 01:46We all know everyone on this zoom
• 01:49knows about the problem of NAFL and
• 01:52Nash also impacting probably at least
• 01:55one in three Americans that goes
• 01:57on to develop into inflammation,
• 02:00fibrosis,
• 02:01hepatocellular carcinoma
• 02:02and stage liver disease.
• 02:05And it's probably even more common.
• 02:08Than what we think.
• 02:09And so this is a study that
• 02:11is impressed by Kit Peterson.
• 02:13The threshold for non alcoholic
• 02:15fatty liver disease was defined by
• 02:18the Dallas Heart Group as 5.5% and
• 02:21studies that kit has done with Doug
• 02:23Rothman on Sylvie Dufour at our
• 02:26four Tesla instrument in young lean
• 02:29healthy individuals actually finds
• 02:31the 95th percentile for liver fat
• 02:34and healthy individuals is 1.85%.
• 02:37So I think actually.
• 02:38We're significantly underestimating
• 02:40the degree of fatty liver and
• 02:44what kid Peterson has shown in
• 02:46this study is even when you
• 02:49have 1.85% liver fat or higher,
• 02:51it's associated with alterations in
• 02:53insulin resistance and plasma like
• 02:56proteins and high triglycerides,
• 02:58high cholesterol.
• 03:00So what I first want to the first
• 03:02piece of my talk is about how muscle
• 03:05insulin resistance actually can lead
• 03:07to not only dyslipidemia and atherogenesis,
• 03:09but a fatty liver simply by changing how
• 03:13the energy that we ingest is stored.
• 03:15When you're just carbohydrate,
• 03:17how is it then stored in liver
• 03:20and muscle as glycogen or fat?
• 03:22This is what we do.
• 03:24We screen healthy young individuals.
• 03:26Most of these are Yale undergraduates.
• 03:28They come in for our studies.
• 03:30We give them a drink of glucose.
• 03:31We measure insulin.
• 03:32We can assess insulin sensitivity index,
• 03:34and by definition we have.
• 03:36You have a nice bell shaped
• 03:38distribution as bottom quartile or
• 03:39resistant top world tile sensitive.
• 03:41We asked the very simple question
• 03:43when they ingest carbohydrate.
• 03:45Do these folks here who are
• 03:47resistant store the ingested
• 03:49carbohydrate differently from the
• 03:50ones in the top four tile?
• 03:53We bring them into the
• 03:54hospital research unit,
• 03:55measure plasma glucoses in both the
• 03:58resistant and yellow and sensitive in blue.
• 04:01No perceptible differences
• 04:03in glucose concentrations,
• 04:05but This is why it's at the
• 04:07expense of hyperinsulinemia,
• 04:08so the resistant individuals
• 04:09have to pump out twice the
• 04:12amount of insulin to
• 04:14maintain normal glycemia.
• 04:15Using carbon NMR methods,
• 04:16we have developed over the years we
• 04:19cannon invasively measure glycogen
• 04:21synthesis in muscle and liver.
• 04:23We find a profound defect in glucose
• 04:26getting into muscle glycogen no
• 04:28difference in glucose ingested,
• 04:30glucose getting into liver
• 04:32glycogen using proton annamar,
• 04:34we can actually quantify fat both
• 04:36inside the liver cell is probably
• 04:38the gold standard for assessing
• 04:40liver fat in noninvasively in humans,
• 04:43and we see this over 2 fold
• 04:44increase in liver fat.
• 04:46In the resistant individuals falling again,
• 04:48identical carbohydrate ingestion,
• 04:49and this is due to denovo lipogenesis.
• 04:53We have some deuterated heavy water
• 04:56in this milkshake that they ingest,
• 04:59and we can track the deuterium
• 05:02into the plasma triglyceride
• 05:03and quantify denovo lipogenesis.
• 05:05So this is the conversion of ingestive
• 05:09carbohydrate to fat in liver.
• 05:11And when you make more fat in the liver,
• 05:15it's exported and this results in
• 05:18increased plasma triglycerides
• 05:20and reduction in HDL.
• 05:22So conceptually, this is what we have here,
• 05:24so this is where you want to be.
• 05:27If you're in the top quartile,
• 05:28you ingest your carbohydrate.
• 05:30It's stored as glycogen in muscle and liver,
• 05:34and if you're in that bottom quartile
• 05:36and this is one in four Americans,
• 05:38and if you're overweight or obese,
• 05:39you're almost certainly already
• 05:41instantly resist since you have instant
• 05:43resistance to to ectopic lipid and muscle,
• 05:45you can't store that ingested
• 05:48carbohydrate as muscle glycogen,
• 05:50it's diverted to the liver hyperinsulinemia.
• 05:53Gives up the all the enzymes that
• 05:55are involved in conversion of
• 05:57glucose to fats with denoble.
• 05:58Lipogenesis is upregulated and this
• 06:01results in the high triglycerides
• 06:04and the reduction HGL this is
• 06:07your atherogenic dyslipidemia.
• 06:08That's going to lead to premature
• 06:10cardiovascular disease in your 50s and 60s,
• 06:12and with time this is what now is now.
• 06:15The most common cause of of
• 06:17of chronic liver disease.
• 06:18Non alcoholic fatty liver disease.
• 06:20So starting in muscle leading
• 06:22to fat and liver.
• 06:23And then now Phil,
• 06:25leading to Nash and potentially
• 06:27liver cirrhosis.
• 06:28Can we do anything about this?
• 06:30Well, to test this hypothesis,
• 06:33if we're right muscle and
• 06:34some resistance drives liver,
• 06:36fat generation,
• 06:36a study we've done many years
• 06:39ago looking at the same lean,
• 06:41instant resistant individuals,
• 06:42these are with two parents with diabetes.
• 06:45If you're resistant,
• 06:46you're young and you're young and
• 06:48you have parents with diabetes.
• 06:49Insulin resistance is the best
• 06:51predictor for whether or not you're
• 06:52going to go on to develop diabetes.
• 06:54And a study we did some years ago.
• 06:56Jean Luca Persaingan exercised these
• 06:58young healthy individuals and showed
• 07:00that we could normalize insulin,
• 07:02stimulated muscle glycogen synthesis
• 07:04so we can fix this defect in muscle.
• 07:08Insulin resistance,
• 07:09and so Rasmus Rubal was a fellow
• 07:13from Denmark,
• 07:15basically took the same insulin resistance.
• 07:17Individuals put them on a Stairmaster,
• 07:19exercise them for 45 minutes.
• 07:22A single bout is able to open up the
• 07:24door to glucose transport and muscle,
• 07:26and what Rasmus found in this
• 07:28study is these resistant
• 07:29individuals were able to take the ingested
• 07:32carbohydrates stored as muscle glycogen,
• 07:35and that resulted in reduction
• 07:37and denovo lipogenesis.
• 07:38Pain reduction liver fat.
• 07:40So this is proof of the hypothesis
• 07:42that if we fix muscle and resistance
• 07:45we can reduce DNA and reduce liver fat.
• 07:48Vine carbohydrate ingestion?
• 07:51So what about fatty liver
• 07:52and type 2 diabetes?
• 07:54And so we've spent a lot of time
• 07:55trying to understand mechanisms.
• 07:57Why is it that a lot of our patients,
• 07:59not all, but most of them with fatty liver,
• 08:01have diabetes and dyslipidemia,
• 08:03and this is kind of the molecular
• 08:06basis for insulin resistance.
• 08:09So insulin binds the receptor and it
• 08:12causes autophosphorylation the receptor.
• 08:14The substrate for this receptor
• 08:16is instant receptor substrate 2,
• 08:17which undergoes tyrosine
• 08:19phosphorylation binds π.
• 08:21The kinase and through a cascade
• 08:23activates glycogen synthesis and through
• 08:25transcription regulation of FOXO,
• 08:27it puts the brake on gluconeogenesis
• 08:29and work starting with ARM and Samuel,
• 08:32who was in the Investigational medicine
• 08:34program with me and received his pH.
• 08:37D on top of his MD.
• 08:39He was a trained endocrinologist
• 08:41when he came to work with me,
• 08:44found that it was specifically
• 08:46how fat and liver causes instant
• 08:48resistance was its accumulation of the.
• 08:51This product I asoli scroll.
• 08:53This is the penultimate step in
• 08:56triglyceride synthesis and what
• 08:57environment showed it activates protein
• 08:59kinase epsilon protein kinase C epsilon,
• 09:02which binds the receptor and
• 09:04inhibits the receptor kinase.
• 09:06And what Garmin did was to prove this.
• 09:08He knocked down PKC Epsilon and
• 09:10got protection from lipid induced
• 09:13hepatic insulin resistance.
• 09:15The last question in this was how is
• 09:18epsilon inhibiting the receptor kinase
• 09:20and this is where another MD PhD.
• 09:23Student Max Peterson working with Jesse
• 09:27Reinhardt doing untargeted phosphoproteomics,
• 09:30we discovered that PKC epsilon directly
• 09:32binds to the receptor and phosphorylates.
• 09:36This green loop is the instant receptor the
• 09:39catalytic domain of the instant receptor.
• 09:41These three tyrosines are required
• 09:43for insulin activation of the
• 09:46receptor and what Jesse and and Max
• 09:49and Brandon Gassaway found that
• 09:51Epsilon purified Epsilon.
• 09:53Cost 4 relates the streaming 1160 which
• 09:55got us very excited because it's in
• 09:58the catalytic domain of the instant receptor.
• 10:01The other thing that got us excited
• 10:03is this 3 inning is conserved all the
• 10:05way from humans down to fruit flies as
• 10:08well as the three tyrosines in that
• 10:10are required for insulin activation
• 10:12of the kinase and the receptor.
• 10:15To prove this,
• 10:16Max knocked the the three nine to
• 10:19glutamic acid to mimic a phosphorylation
• 10:21event and showed that it was.
• 10:24Receptor kinase dead.
• 10:25He did the reverse experiment,
• 10:27mutated the three inch when alanine and
• 10:30she got protection from PKC epsilon
• 10:32induced reduction in receptor kinase
• 10:34activity and then we made the mouse
• 10:36and this is the three inning to the
• 10:39homologous site the 11:50 site to an alanine.
• 10:42I won't show you the date it's published
• 10:44regular child fed mice are perfectly
• 10:46normal but when you feed these mice
• 10:48a high fat diet this is what we see.
• 10:50This is doing a hyperinsulinemic uyemura
• 10:53clamp we give insulin. To these mice.
• 10:55Normally it should suppress glucose
• 10:57production and this is what we
• 10:58always see with high fat feeding,
• 11:00fat accumulation, fatty liver and the mice.
• 11:02Insulin resistant as defined by inability
• 11:04of insulin to put the brake on,
• 11:06have had a glucose production.
• 11:08In contrast, same amount of liver fat.
• 11:11These these single mutation
• 11:13in three to an alanine.
• 11:14Normal suppression of the paddock glucose
• 11:17production so they're protected from
• 11:20fat induced hepatic insulin resistance
• 11:22with the single amino acid mutation.
• 11:24Follow up studies done by a graduate student.
• 11:27Coonley you in the lab has shown working with
• 11:30Jonathan Bogan to do Compartmentation to see.
• 11:32OK, there's different isoforms
• 11:34of these types of literals.
• 11:35What is the compartment that's
• 11:37actually triggering the fatty acid?
• 11:39The lipid induced insulin resistance?
• 11:41We found that it was the SN12
• 11:43dice of glycerols,
• 11:44as opposed to the 2-3 or
• 11:47the 1/3 stereo isomers,
• 11:48and it was specifically
• 11:50in the plasma membrane.
• 11:52The yes and 1/2 Dags accumulating
• 11:54the plasma membrane.
• 11:56This is what leads the PKC epsilon
• 11:58translocation and that leads to the
• 12:01phosphorylation of the three enine
• 12:03and in defects in receptor kinase
• 12:06activity and insulin resistance.
• 12:08This concept is very important.
• 12:11Very important.
• 12:11I'll make a couple points here.
• 12:13It's all about location.
• 12:14So if the S1 Dags build up
• 12:17in a lipid droplet fraction,
• 12:19they do not cause insulin
• 12:20resistance and we see this.
• 12:21We see this in some of our fatty
• 12:23liver patients that do not have
• 12:25a paddock instant resistance,
• 12:26and that's because the fact and even
• 12:28the Dags are in are in a lipid droplet.
• 12:31It's only the plasma membrane
• 12:32Dyson Glycerols that trigger
• 12:33the insulin resistance.
• 12:35And this explains many of the
• 12:37confusion literature the HDAC 3.
• 12:38Lock down which Lazar made huge
• 12:40fatty liver insulin resistance.
• 12:42We've shown CGI 58 knocked down.
• 12:44This is a cofactor for AGL,
• 12:46the light base and the huge fat accumulation.
• 12:49Knowing some resistance and most
• 12:51recently we showed when you have knockout
• 12:53of the microsomal transfer protein.
• 12:55This is involved when the Assembly of the
• 12:58lipid particle again huge lipid accumulation,
• 13:01no insulin resistance because
• 13:03it's all in the lipid droplet.
• 13:05OK,
• 13:05so we've gone on to basically establish this.
• 13:08In liver.
• 13:11**** Liu, shown in the same thing,
• 13:13is happening with short term high
• 13:15fat feeding and the fat cell.
• 13:16Same mechanism.
• 13:17712 PKC epsilon transportation another
• 13:20graduate student showed that this is
• 13:23what's happening in skeletal muscle.
• 13:25Same mechanism.
• 13:26SM12,
• 13:26PKC hitting the receptor and another
• 13:29MD PhD student has found that the
• 13:32same thing is happening in the kidney.
• 13:35We don't think about the kidney
• 13:36as being instant responsive.
• 13:37It is and it gets instant resistant and
• 13:40Brandon has shown that it's the same.
• 13:42Mechanism SM12 daggs in the membrane.
• 13:45Activating PKC epsilon.
• 13:49Activation of Epsilon does many other things
• 13:52besides the receptors to work by Jesse
• 13:54Reinhard and his graduates from Gassaway.
• 13:56Working with us showed that epsilon hits
• 13:59many other targets besides receptors, so it
• 14:01could actually explain many other things.
• 14:03Going on post receptor defects
• 14:06and insulin action.
• 14:07I just wanted to share this with you
• 14:09because you have to ask the question,
• 14:10why has insulin resistance exists?
• 14:13Why has it? Why does it exist?
• 14:15Why is that three name being conserved
• 14:17all the way from humans to fruit flies?
• 14:19And so here is a hypothesis I
• 14:21want to share with you.
• 14:22Where with starvation this pathways
• 14:25activated every model you starve,
• 14:29gets fatty liver that goes from mice,
• 14:31rats to humans.
• 14:32During starvation you get fatty liver.
• 14:35This pathway gets activated,
• 14:36you get instant resistance.
• 14:37The starvation and this maintains glucose
• 14:40in the bloodstream for the for the CNS,
• 14:45the brain and the red blood cells.
• 14:46And this is starvation induced in some
• 14:50resistances and protective for survival.
• 14:54OK.
• 14:54And then finally I just want to
• 14:56end up here by sharing with you 2.
• 14:59How do we fix this?
• 15:01And if we're right, the two bad actors,
• 15:04one of them diacylglycerol in the plasma
• 15:07membrane, the other is acetyl Co.
• 15:08Way which directly activates
• 15:10perfect carboxylase.
• 15:10They don't have much.
• 15:11I don't have enough time to talk about that,
• 15:13and if we're right,
• 15:15if we can reduce these moieties
• 15:17in the parasite,
• 15:18we can fix all the metabolic dysfunction
• 15:21of metabolic syndrome and type 2 diabetes.
• 15:23One way to do that is reduce energy intake.
• 15:26The other is revving up the TCA cycle.
• 15:29So here as a study that we did years ago,
• 15:33Kit Peterson,
• 15:34we took patients with fatty liver,
• 15:35put them on a 1200 calorie diet in.
• 15:38These are type 2 diabetics,
• 15:40fast and hyperglycemia.
• 15:41This is due to increased hepatic
• 15:43glucose production due to increased
• 15:45gluconeogenesis and insulin resistance
• 15:47and ability to insulin suppress glucose
• 15:50production and 1200 calorie diet.
• 15:52They only had to lose 10% of
• 15:54their body weight, sometimes 8%.
• 15:56We fix fasting hyperglycemia,
• 15:58we it's due to reduction in patient
• 16:00glucose production due to decreased
• 16:03gluconeogenesis and we normalize insulin's
• 16:05ability to suppress glucose production.
• 16:08So again,
• 16:09three points here for the clinicians,
• 16:1110% weight reduction was sufficient
• 16:13to get rid of all the liver fat,
• 16:16and this is now, I think,
• 16:18been replicated many,
• 16:19many times.
• 16:19It's in the textbooks and the second thing
• 16:22this again 2005 to almost 20 years ago.
• 16:25Every patient with type poorly controlled
• 16:27type 2 diabetes has too much fat and liver.
• 16:30Normal as I showed you one point 8%,
• 16:32it's about 10 times normal and
• 16:35again 10% rate reduction is able
• 16:37to get rid of that liver fat.
• 16:39You get rid of the liver fat.
• 16:40You fix diabetes.
• 16:41Finally, how do we fix it?
• 16:44It's again,
• 16:45unfortunately we all know weight loss
• 16:47is very hard to achieve in the clinic.
• 16:50Are there other ways?
• 16:51And this is what I'll share
• 16:52with you in the last two minutes here.
• 16:54If we Rev up the mitochondria,
• 16:55this is a way of burning the fat to
• 16:57get rid of it, and the first study
• 16:59was done actually by Varman Samuel,
• 17:00who already introduced you to,
• 17:02and we've known about Diane
• 17:04DNP for almost a century now.
• 17:06It's an uncoupler.
• 17:07It promotes dissipates the proton gradient,
• 17:09Revs up fat oxidation, and in this paper
• 17:11of Armin showed it reduced tags and dags.
• 17:14We prevented PKC epsilon activation and
• 17:17proved the paddock insulin sensitivity.
• 17:19DNP is a search with many talk.
• 17:22The main toxicity is on target.
• 17:25It promotes hyperthermia and so we came
• 17:27up with an idea of what if we liver targeted.
• 17:30Can we avoid the toxicity and
• 17:32so in a series of studies done,
• 17:35but we do need to kind of just wrap up
• 17:38so we have time for the next session.
• 17:40This is all published,
• 17:42but we deliver targeted DNP.
• 17:44We're able to prevent the hyperthermia,
• 17:47and it's 50 fold safer than the
• 17:50parent compound.
• 17:51We reverse insulin resistance.
• 17:53This is our second generation compound.
• 17:55It's even tenfold safer.
• 17:57We fix insulin resistance,
• 17:58and this is the key thing for the liver.
• 18:00People.
• 18:00We get rid of inflammation.
• 18:02We get rid of the liver fat and
• 18:04you get reduced liver fibrosis.
• 18:06And so we've developed methods to
• 18:08assess mitochondrial oxidation.
• 18:10Vivo using NMR.
• 18:13Spectroscopy we've shown it safe and non
• 18:16human primates and this paper is impressed.
• 18:19We've shown it actually reduces the
• 18:21how to cellular carcinoma in a aging
• 18:24mouse model and this is Rachel Perry's work.
• 18:26She's now also shown again obesity associated
• 18:28cancers are going through the roof.
• 18:30You get rid of insulin resistance and
• 18:32in two studies this is one of them.
• 18:34Racial has shown it slows down the growth
• 18:36of colon cancer as well as breast cancer.
• 18:39So this is my final slide.
• 18:41You Rev up mitochondrial and.
• 18:43Pulling and liver you reduce liver fat.
• 18:46It's going to be heart healthy.
• 18:47You reduce triglycerides and eldil
• 18:49cholesterol and you secondarily improve
• 18:51muscle and some resistance because you
• 18:53decrease export of that to the muscle.
• 18:55So this is my oh and many other groups
• 18:57are jumping on this now and it's actually
• 19:00it is in clinical trials and it's been
• 19:03shown to be safe and reduce liver
• 19:06fat in humans as a related compound.
• 19:09So most important,
• 19:10slide the collaborators.
• 19:12I was mostly able to acknowledge during
• 19:15my talk and this was that window a year
• 19:18ago when we go maskless before Omicron.
• 19:21Thank you very much for your attention.