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Yale Psychiatry Grand Rounds: Lustman Awards 2024

June 14, 2024
  • 00:00Thanks, Kelly for that
  • 00:02very nice introduction.
  • 00:07Well, thank you everybody for being here.
  • 00:08I'm excited to talk to you
  • 00:10about my research today.
  • 00:11I'm going to talk to you a bit about the
  • 00:15histone deacetylase 6 and it's work in PTSD.
  • 00:19We have some exciting translational
  • 00:21evidence of suppression in PTSD
  • 00:24for this enzyme we term HDAC 6.
  • 00:28So you know PTSDI think most of us in
  • 00:31psychiatry are familiar with this disorder,
  • 00:33but it is anxiety,
  • 00:35it's under the anxiety disorder
  • 00:38diagnosis within our DSM 5.
  • 00:40The treatments that we have currently
  • 00:42that are FDA approved and most commonly
  • 00:45used are primarily symptomatic treatments.
  • 00:48And you know, with the leading treatment
  • 00:50as starting treatment as our SSRIs,
  • 00:52our selective serotonin reuptake inhibitors.
  • 00:55But we know that we only have a 50 to
  • 00:5860% response rate and and that's sort of
  • 01:00on the best end with these treatments.
  • 01:03And, you know,
  • 01:04we have a variety of other symptomatic
  • 01:05treatments we can go to as second,
  • 01:07third, fourth lines to treat
  • 01:09different parts of the disease,
  • 01:11the nightmares, the insomnia, flashbacks.
  • 01:14But we have a hard time really
  • 01:17targeting the entire illness.
  • 01:19Part of that is because this
  • 01:21illness is so pleotropic and,
  • 01:22and presents in so many different ways and,
  • 01:25and at different times.
  • 01:26It can present within, you know,
  • 01:28six months after a trauma,
  • 01:30it anytime after one month after the trauma,
  • 01:32it is considered PTSD and,
  • 01:35and no longer the acute stress diagnosis.
  • 01:37But it can also, you know,
  • 01:38we've seen Vietnam Veterans who
  • 01:40present with symptoms of PTSD
  • 01:4230-40 years after their trauma.
  • 01:45And so how is that, how is that happening?
  • 01:48And how,
  • 01:48how is this all one disorder that
  • 01:50we are trying to treat in one way?
  • 01:52And, and what does that really mean?
  • 01:54And,
  • 01:55and how can we better understand this
  • 01:57disorder and the pathophysiology of it
  • 02:00such that we can target our treatments?
  • 02:03And so I think, you know,
  • 02:04the field as a whole is really starting
  • 02:06to follow in the footsteps of,
  • 02:07of the oncology research and of cancer.
  • 02:09And we're,
  • 02:10I think a little bit behind them
  • 02:12in this precision medicine pursuit
  • 02:13and this pursuit to,
  • 02:15to find targeted treatments
  • 02:17for individuals and,
  • 02:18and where we can really help with that.
  • 02:21I think maybe I'm biased,
  • 02:23but I feel that H Dax and epigenetics,
  • 02:25which I'll get into a bit more
  • 02:27and utilizing neuroimaging,
  • 02:28non invasive imaging modalities to be
  • 02:31able to better understand the brain,
  • 02:33allow us to,
  • 02:35to really better understand these
  • 02:37disorders on an individual basis.
  • 02:39And so I think, you know,
  • 02:41that allows us to hopefully down
  • 02:42the road be able to stratify,
  • 02:44stratify medications based on
  • 02:47an individual's pathophysiology
  • 02:48rather than trying to treat this,
  • 02:51especially this pleiotropic
  • 02:52disease as one and one only.
  • 02:56So epigenetics and histone deacetylases,
  • 02:58they're a class of 18 enzymes and they're,
  • 03:01they're canonically known as
  • 03:02epigenetic enzymes because of their
  • 03:05role deacetylating or removing
  • 03:06acetylomorides from the lysine
  • 03:08tails on the histone core proteins.
  • 03:11And so these tails are very lysine rich.
  • 03:13They can be added an acetylm Y,
  • 03:15they can be added or removed and that
  • 03:17alters how closely the DNA is held
  • 03:19and whether or not an open reading
  • 03:21frame can be formed and therefore
  • 03:24genomic transcription can occur.
  • 03:25So the the H docs as they're known,
  • 03:28it is 18 enzymes.
  • 03:30However, within the H doc classes,
  • 03:32there are four classes and they
  • 03:34all function very differently.
  • 03:36So I think H docs one through
  • 03:38three are sort of very much this,
  • 03:41this epigenetic role, but one that
  • 03:42we are going to talk about today.
  • 03:44H doc 6 is part of class 2B and it
  • 03:48actually is more more predominant in
  • 03:51the cytoplasm than in the nucleus.
  • 03:52So it does shuttle between the cytoplasm and
  • 03:55the nucleus of the cell and of the neuron,
  • 03:57but in the brain,
  • 03:58but it is actually more functional
  • 04:00in the cytoplasm.
  • 04:01So it's not quite an epigenetic enzyme in the
  • 04:04in the way that we think about epigenetics.
  • 04:07But it was originally found to be a
  • 04:11microtubule deacetylase in its role
  • 04:13of deacidylating the alpha tubulin at
  • 04:15lysine 40 and in that it stabilized
  • 04:18and destabilized alpha tubulin and
  • 04:20part of the microtubule structure.
  • 04:22And so that allows for both
  • 04:24the growth cone formation,
  • 04:25so cell,
  • 04:27cell growth as well as cell some
  • 04:30of cell movement through filopod
  • 04:32formation and then also replication.
  • 04:35As we know,
  • 04:37mitophase and anaphase rely
  • 04:39predominantly on the microtubules
  • 04:42and then it also has a role in
  • 04:45autophagosome degradation and and
  • 04:47it was found then through some
  • 04:49studies about 10 years ago to be
  • 04:51abundantly expressed within the
  • 04:52serotonergic neurons of the brain and
  • 04:54so within the dorsal Raphae nucleus.
  • 04:56They found this,
  • 04:58this highly studied,
  • 05:00highly cited study found that H
  • 05:03.6 was very highly expressed in
  • 05:05the dorsal Raphae nucleus and
  • 05:06within the serotonergic neurons.
  • 05:08And moreover,
  • 05:09they found that if they knocked
  • 05:11it out both constitutively with
  • 05:13a a Cree driven deletion of H .6
  • 05:15in mice as well as if they did a
  • 05:18pharmacologic inhibition with H .6
  • 05:20selective inhibitors that they could
  • 05:22promote different and a less anxiety
  • 05:25prone phenotype of these mice.
  • 05:27So this led to this understanding
  • 05:29that you know there may be something
  • 05:32going on here with H .6 in emotional
  • 05:34regulation and an anxiety regulation
  • 05:37and they began to better understand
  • 05:40that H .6 was needed for the role
  • 05:43of the glucocorticoid receptor.
  • 05:45And through that and through a
  • 05:48few other studies that were done
  • 05:50over the next couple of years,
  • 05:51this role for HDAC 6IN deacidylating and
  • 05:55therefore stabilizing or destabilizing
  • 05:57the HSP 90 glucocorticoid receptor and
  • 06:01FKBP 5 two complex was better understood.
  • 06:04And So what actually under happens
  • 06:07is the HDAC 6 removes this acetyl
  • 06:10moiety from HSP 90,
  • 06:11which is our heat shock protein that
  • 06:13is a a commonly known chaperone protein
  • 06:15for the glucocorticoid receptor.
  • 06:17And that allows it to complex with
  • 06:20the glucocorticoid receptor when
  • 06:22a glucocorticoid such as cortisol
  • 06:23binds and with FKBB 5.
  • 06:25And that allows this translocation of
  • 06:27the glucocorticoid receptor from the
  • 06:29cytoplasm into the nucleus and then
  • 06:32therefore the glucocorticoid response
  • 06:33elements to be transcribed on the genome.
  • 06:36And so the thought was and,
  • 06:38and based on their deletion studies,
  • 06:40they, the sort of the predominant
  • 06:43understanding was that an increase in
  • 06:45H Doc 6 therefore would lead to this
  • 06:47increase in stress susceptibility
  • 06:49because we felt that an increase
  • 06:51in H Doc six would allow more of
  • 06:54these GR ES to be expressed.
  • 06:57And so to better understand that in in the
  • 07:01in vivo in humans as well as in animals,
  • 07:04there is this novel tracer that
  • 07:06has been developed out of MGH and
  • 07:08the Martinez imaging Center there.
  • 07:11And they developed this tracer
  • 07:13called Beveristat,
  • 07:14which is a fluorine 18 labeled PET
  • 07:17suitable radio lag and targeting HDAC 6.
  • 07:20And so this tracer has had had gone
  • 07:22into humans first in Belgium and
  • 07:24then we redid quite a bit of the test
  • 07:27retest studies here at Yale as well.
  • 07:30And we decided to put this into to
  • 07:32PTSD both in humans as well as in
  • 07:34a rodent model to better understand
  • 07:36how HDAC 6 and if we could is,
  • 07:38is acting both in humans in PTSD.
  • 07:42And so our original hypothesis was
  • 07:44that the stress susceptibility or PTSD
  • 07:47symptoms would be correlated with
  • 07:48an increase in HDAC 6 based on these
  • 07:51findings from these 2012 and 2015 papers.
  • 07:54And we believed that,
  • 07:56you know,
  • 07:57this translational imaging would
  • 07:58allow for this visualization
  • 08:00and quantification of H .6.
  • 08:01And so the rodent model that we chose to
  • 08:03use was a single prolonged stress model.
  • 08:06I used predominantly all male
  • 08:08Sprite Dolly rats at this point.
  • 08:10That's a,
  • 08:10we do need to go into females of rats.
  • 08:13I, I am not, that's not lost on me,
  • 08:16but for the,
  • 08:16for the proof of principle of this study,
  • 08:19we did all males and we use the
  • 08:21single prolonged stress model
  • 08:22for a couple of reasons.
  • 08:23One is that it's well validated in in rats,
  • 08:27which we cannot use mice as well with
  • 08:30PET imaging due to the size of the brain.
  • 08:33The other is that I felt that it
  • 08:36really capitulated a nice model
  • 08:37of the pro anxiety and the hyper
  • 08:40arousal symptoms of PTSD.
  • 08:42And it also recapitulated this single
  • 08:44stress event rather than some of the
  • 08:48more prolonged stress paradigms that
  • 08:51I think sometimes lead to more of a
  • 08:54depressive phenotype rather than a
  • 08:56a stress or anxiety and PTSD like phenotype.
  • 08:59So this procedure involves restraining
  • 09:01an animal for 120 minutes,
  • 09:04putting them in a tank by themselves
  • 09:06to swim for 20 minutes,
  • 09:07letting them rest for 15 minutes.
  • 09:09And then they are exposed to diethyl
  • 09:11ether until they lose consciousness.
  • 09:13At which point they are single housed
  • 09:15and untouched with free access to
  • 09:17food and water on a traditional 12
  • 09:19hour light dark cycle for seven days.
  • 09:21And it has been shown repeatedly in
  • 09:23the literature that at this point,
  • 09:25after seven days, they will demonstrate
  • 09:28APTSD like phenotype or a hyper arousal,
  • 09:30high anxiety like phenotype.
  • 09:34So the first experiment that
  • 09:36we did was really, you know,
  • 09:37the, the typical experiment,
  • 09:38I think where, you know,
  • 09:40we took two groups of animals.
  • 09:41We had one group that was stressed.
  • 09:43We had one group that was controlled.
  • 09:44They were handled both similarly
  • 09:46leading up to the stress day.
  • 09:48After the stress day, the,
  • 09:49the control animals were handled,
  • 09:51but no but continue to remain double housed,
  • 09:54but we're not single housed after that.
  • 09:56And the stressed animals were
  • 09:58stressed and then single housed
  • 10:00and not handled after that point.
  • 10:02They then both underwent open field
  • 10:04behavioral testing and H .6 pet on
  • 10:06the same day and the following day
  • 10:07they were sacrificed and their brains
  • 10:09were removed for post mortem analysis.
  • 10:13And you know,
  • 10:15pretty much as we expected based
  • 10:16on the literature,
  • 10:17we did see changes consistent with
  • 10:20anxiety phenotype and consistent with
  • 10:22what was shown in the literature
  • 10:24to be this PTSD like model in
  • 10:27our behavioral testing.
  • 10:29And then interestingly,
  • 10:31when we did the H stack 6
  • 10:33imaging with Beveristat,
  • 10:34we found a decrease in the stressed
  • 10:37animals in these key regions of
  • 10:38the brain that we identified.
  • 10:41So and we didn't see, you know,
  • 10:43there was a slight decrease in
  • 10:44the cerebellum in the whole brain,
  • 10:46but not statistically significant,
  • 10:47unlike the other key regions that
  • 10:50are affected more under stress
  • 10:52such as the amygdala,
  • 10:53hippocampus,
  • 10:54limbic cortex and the brain stem,
  • 10:56notably where the dorsal Raphae
  • 10:58nucleus and serotonergic neurons
  • 10:59are predominantly located.
  • 11:00And this was really surprising to us
  • 11:02given our original hypothesis was
  • 11:04that there would be an increase.
  • 11:06And so because of this and because
  • 11:08of the quantification with PET
  • 11:10in an animal without an arterial
  • 11:12input function to rely on,
  • 11:13it's a bit more difficult.
  • 11:16We decided to do it within subject analysis.
  • 11:18And so I took rats and we
  • 11:21I imaged them at baseline,
  • 11:22we stressed them and then imaged them
  • 11:24again to see what this would look like.
  • 11:26And we actually found similarly
  • 11:28the same thing. So we found both.
  • 11:30We found a decrease in the striatum
  • 11:33and amygdala, hippocampus,
  • 11:34as well as a non significant decrease
  • 11:37but trending in brain stem and limbic cortex.
  • 11:39And when we stratified all of these
  • 11:41rats by low anxiety and high anxiety,
  • 11:43we found that there was a difference.
  • 11:44There was a slightly more of a
  • 11:47decrease in the high anxiety group
  • 11:49as compared to the low anxiety
  • 11:50in most of the regions,
  • 11:52although it was not always
  • 11:53statistically significant.
  • 11:57So this led to this next question,
  • 11:59which was, you know,
  • 12:00are we catching these animals?
  • 12:02Are we catching this too late?
  • 12:04You know, maybe this is a,
  • 12:05this is a compensatory decrease after
  • 12:07an increase and maybe the the knockouts
  • 12:10that were done before stress in these
  • 12:13preclinical studies were knocking out
  • 12:15H stack 6 before it increased and
  • 12:17therefore they were seeing this response.
  • 12:20And now we're seeing sort of the fallout,
  • 12:21which is the a larger swing in the
  • 12:24opposite direction because we really
  • 12:25were trying to understand, you know,
  • 12:28why are we seeing this decrease?
  • 12:30So the next study was to do
  • 12:32an acute stress study.
  • 12:34And so we took the animals,
  • 12:35we split them into two groups,
  • 12:36again, did the same paradigm,
  • 12:38stress versus control,
  • 12:39but instead only waited 48 hours before
  • 12:42doing behavioral testing and imaging.
  • 12:44And as predicted based on the literature,
  • 12:47at 48 hours,
  • 12:48they do not show a significant
  • 12:49difference in the anxiety phenotype.
  • 12:51So they really don't look that much
  • 12:53different than the controls in the way that
  • 12:55they're interacting with their environment.
  • 12:56However,
  • 12:57they do show significant differences
  • 12:59or very close to significant,
  • 13:01I should say.
  • 13:02They're they're not quite there,
  • 13:03but in the acute stress time period.
  • 13:07So as you can see,
  • 13:09they show almost equivalent brain changes
  • 13:11of H .6 to the PTSD animals at 48 hours.
  • 13:15So this was really striking to
  • 13:17us because it demonstrated to us
  • 13:19that before the behavior changes,
  • 13:21we are seeing these brain changes
  • 13:23in H .6 that are preceding the
  • 13:26actual behavior of PTSD like model.
  • 13:28And we also did Western blocks which
  • 13:31demonstrated that at two days post
  • 13:33stress in the prefrontal cortex we
  • 13:35were seeing a significant decrease
  • 13:37in the glucocorticoid receptor.
  • 13:39This was total cell,
  • 13:41total tissue glucocorticoid
  • 13:43receptor concentration,
  • 13:44which I think is a little bit hard
  • 13:45to to understand exactly what that
  • 13:47means when we're talking about a
  • 13:48translocation from the cytoplasm to
  • 13:50the nucleus rather than up or down.
  • 13:52But I think it was, you know,
  • 13:53is it interesting finding to go along
  • 13:55with this decrease in HDAC 6 as well.
  • 14:00So to change over to humans,
  • 14:03this is what we found in the animals.
  • 14:04And now we were interested to see does the,
  • 14:07do these findings hold in humans
  • 14:09with PTSD as they did in rats?
  • 14:11Because again,
  • 14:12we don't know what the translation
  • 14:14is necessarily from rat rats to humans.
  • 14:16We know that the rodent models of
  • 14:19PTSD are good, but not always great.
  • 14:21And we know that the pathophysiology of
  • 14:24PTSD in particular as a psycho pathology
  • 14:26and as a psychiatric illness is,
  • 14:28is not one that is well recapitulated in
  • 14:31animal models consistently because of its
  • 14:34difficulty to really get to the the human.
  • 14:37I think the human nature of the
  • 14:39flashbacks and the memories are
  • 14:40very difficult to know that we're,
  • 14:41we're actually putting that into an animal.
  • 14:45And so moving into human work,
  • 14:47we, we took a sub,
  • 14:50took three groups of humans,
  • 14:51healthy controls, trauma,
  • 14:53exposed controls and PTSD.
  • 14:55They were relatively well matched.
  • 14:58There were some slight age differences,
  • 14:59but otherwise relatively well matched
  • 15:01groups with the exception notably of course,
  • 15:04of their scores.
  • 15:05So we looked at key PTSD scores that we use
  • 15:10particularly in research such as the CAPS 5,
  • 15:12the PCL 5 and then we did a number
  • 15:14of others and addressed the HAM
  • 15:16DMA to better understand their
  • 15:18anxiety and depressive phenotype.
  • 15:21And when we looked at this,
  • 15:25we,
  • 15:25So we imaged all of these individuals
  • 15:27and found that we did see significant
  • 15:30decreases in the PTSD individuals as
  • 15:33compared to the healthy controls.
  • 15:35But we also saw decrease in
  • 15:38the trauma controls,
  • 15:39most notably in the dorsal Raphae nucleus.
  • 15:41And we have the dorsal Raphae
  • 15:43nucleus we know is sort of a,
  • 15:45it's a long,
  • 15:47a long nuclei across the brain stem.
  • 15:49And so this encompasses both the midbrain
  • 15:53sort of locus and the ponds locus.
  • 15:55And so we for the purposes of
  • 15:56quantification of the imaging,
  • 15:57we have them separated.
  • 15:59But it was notable to us both
  • 16:01that there was a decrease which
  • 16:03was consistent with the animals,
  • 16:05but also that that this was lower
  • 16:08in the trauma controls and not just
  • 16:12in the PTSD and that there was no
  • 16:14difference between the trauma control
  • 16:16and the PTSD significant or statistically.
  • 16:18Sorry.
  • 16:20So going back to our original hypothesis,
  • 16:23why are we seeing,
  • 16:24you know, this?
  • 16:25We originally hypothesize we
  • 16:26would see higher HDAC 6.
  • 16:28We're now seeing lower HDAC 6.
  • 16:31And what what does that mean?
  • 16:32And so,
  • 16:33you know,
  • 16:34we had originally hypothesized
  • 16:35that that that increased HDAC 6
  • 16:38would relate to increased stress
  • 16:40susceptibility and more translocation.
  • 16:42But we also have this prior evidence from
  • 16:45another excellent resident and physician,
  • 16:48scientist Doctor Shivani Bhatt,
  • 16:50and with her mentorship under
  • 16:53Doctor Cosgrove that looked
  • 16:55at some cortisol imaging.
  • 16:57And so this was looking at an enzyme
  • 16:59that produces cortisol in the brain
  • 17:01and they found that this was increased
  • 17:03in the brain in PTSD individuals
  • 17:05as compared to trauma controls.
  • 17:07So you know,
  • 17:09there's a,
  • 17:10I'm wondering now we're
  • 17:11wondering if there's a
  • 17:12chance that this is a compensatory
  • 17:14response if there is increased cortisol
  • 17:17centrally and that therefore the HDAC 6 is,
  • 17:20is sort of trying to down regulate that
  • 17:23response and decreasing the glucocorticoid
  • 17:26receptor translocation into the nucleus.
  • 17:29And so, you know, is that is that,
  • 17:31is that a possibility?
  • 17:33I think we, we don't know yet,
  • 17:35but that's, that's sort of one
  • 17:38response to this hypothesis.
  • 17:40And, and you know,
  • 17:41the difference between the trauma
  • 17:43control and the PTSDI think one,
  • 17:45one note that we're also interested in is,
  • 17:48is could this lower H .6 be a
  • 17:51trauma marker that's indicating
  • 17:53this predisposition for PTSD?
  • 17:55You know, we don't we,
  • 17:56we know that many people who undergo
  • 17:59multiple traumas are more likely after
  • 18:01their first traumas or after childhood
  • 18:03trauma to acquire PTSD later in life,
  • 18:06either from that trauma or
  • 18:07from subsequent traumas.
  • 18:08And so, you know,
  • 18:10is this evidence that this may be one of the
  • 18:14changes that is predisposing them to PTSD?
  • 18:16Certainly not all individuals.
  • 18:17Some individuals,
  • 18:18it is their first trauma and
  • 18:20only trauma that triggers PTSD,
  • 18:22of course.
  • 18:23But what you know what,
  • 18:25what's happening here?
  • 18:25Why are we seeing this change both in
  • 18:28the animals at this acute period and in
  • 18:30the humans and these trauma controls,
  • 18:32as well as in the PTSD individuals?
  • 18:34And so I think that's part of an
  • 18:37ongoing question that we need more,
  • 18:40more studies to better answer.
  • 18:41But this was an exciting
  • 18:43first step to to understand
  • 18:48in summary, you know,
  • 18:49we contrary to the hypothesis,
  • 18:51we now see lower levels of
  • 18:54HDAC 6 both in trauma and in,
  • 18:57in following trauma in
  • 18:58both humans and in animals.
  • 19:00These do we do consider these
  • 19:02pretty robust findings given the
  • 19:04reproducibility across multiple cohorts
  • 19:06of animals within subject and across
  • 19:09groups as well as within humans.
  • 19:11And then, you know,
  • 19:12this would imply that there's a
  • 19:14decreased glucocorticoid receptor
  • 19:16translocation into the nucleus and,
  • 19:19and we have these hypothesis about
  • 19:21possibly a compensatory mechanism
  • 19:22due to increased central cortisol,
  • 19:25but I think more studies are needed
  • 19:27to better understand that full system.
  • 19:31And with that, I'd like to thank
  • 19:32you all for listening. And I'll,
  • 19:34I think we have time for questions.
  • 19:37So I can take any questions.
  • 19:38And of course,
  • 19:39thank both Doctor Cosgrove and Dr.
  • 19:41Matt Dugante, who's sitting here as well,
  • 19:43who's also been a,
  • 19:44a foundational mentor to me and has really
  • 19:47supervised all of the animal work and,
  • 19:50and blended quite a bit of
  • 19:51resources from his lab.
  • 19:52So we thank him as well.
  • 19:54Thank you.
  • 19:58Thank you, Tom for that
  • 20:00really nice introduction.
  • 20:02So I'm I'm excited to be able
  • 20:05to talk to all of you about my
  • 20:07research trying to understand the
  • 20:10role of rare genetic variants
  • 20:12in the development of OCD.
  • 20:19So I'll start just by describing
  • 20:21some of what we already know
  • 20:24about the genetic basis of OCD.
  • 20:26So firstly, we know that it's
  • 20:28moderately to highly heritable.
  • 20:31So this means that the proportion
  • 20:33of the variants in the trait,
  • 20:35basically whether or not someone has OCD,
  • 20:38is determined in part by genetic factors,
  • 20:41and that heritability is higher for the
  • 20:44childhood early onset form of the disorder.
  • 20:47We also know that OCD is polygenic,
  • 20:51so there's a contribution from
  • 20:54estimated hundreds of genes,
  • 20:57all that can contribute to OCD etiology,
  • 21:00but we don't know what
  • 21:02most of those genes are.
  • 21:04And that's ultimately what our
  • 21:06goal is from this research,
  • 21:08is to identify more of those
  • 21:10genes that could tell us about
  • 21:13the underlying biology and could
  • 21:15be potential novel drug targets.
  • 21:18The
  • 21:18other thing we know is that
  • 21:20there's a contribution
  • 21:21from many different types
  • 21:23of genetic variations.
  • 21:25So there's contribution from common
  • 21:28variants that are relatively
  • 21:30common in the human population.
  • 21:32This is what we study with
  • 21:35genome wide association studies.
  • 21:36There's a contribution from rare
  • 21:39inherited variants that are passed
  • 21:42along through families and there's
  • 21:45a contribution from Genovo variants,
  • 21:47which our lab is particularly interested in.
  • 21:52So Genovo genetic variants are not
  • 21:56passed down from parent to child.
  • 21:58They are spontaneous DNA mutations that
  • 22:02arise from an error in DNA replication.
  • 22:06And we all have a few of these,
  • 22:08but they're relatively rare.
  • 22:10And because they're so rare,
  • 22:13they can be used to statistically implicate
  • 22:16genes in the development of a disorder.
  • 22:20And our lab was actually able to
  • 22:23do this previously by looking at
  • 22:26small de Novo variants in OCD.
  • 22:30So by small,
  • 22:31I mean point mutations and and small
  • 22:34insertions or deletions of DNA sequence.
  • 22:37And we found an increase in the rate
  • 22:40of these small de Novo variants that
  • 22:43were likely to damage the protein
  • 22:46product of a gene in children
  • 22:49with OCD compared to controls,
  • 22:51which suggests that this type
  • 22:53of variation was playing some
  • 22:55role in development of OCD.
  • 22:57And we were able to use these de Novo
  • 23:00variants to implicate 2 risk genes that
  • 23:04are thought to be associated with OCD.
  • 23:10So we were interested in using a similar
  • 23:13methodology and applying it to other
  • 23:17types of de Novo genetic variants
  • 23:20and other types of rare variation.
  • 23:22So one thing we were interested in
  • 23:24looking at was copy number variants.
  • 23:26So these are large deletions or
  • 23:30duplications of chunks of DNA sequence,
  • 23:34so much larger changes than
  • 23:36what we were looking at before.
  • 23:38And these have been identified
  • 23:41in patients with OCD,
  • 23:43They've been studied before,
  • 23:46but there's not yet a good evidence
  • 23:50base showing their association
  • 23:52with the development of OCD.
  • 23:56So we opted to use our previous data set,
  • 24:02whole exome sequencing data in
  • 24:06trios with children who had OCD.
  • 24:09So these were families where the
  • 24:12parents were unaffected and the
  • 24:15children have OCD and comparing
  • 24:17this to unaffected control families
  • 24:20with children who don't have OCD.
  • 24:22So we performed quality control
  • 24:26and used this data set to identify
  • 24:31in silico copy number variants,
  • 24:34classify them and do a comparison
  • 24:36of the mutation rates.
  • 24:41So we did quality control with PCA and
  • 24:45made sure the cohorts were ethnically
  • 24:47matched and these are the demographics of
  • 24:50the samples that passed quality control.
  • 24:57And what we found was that rare
  • 25:01deletions were increased occurring
  • 25:04at both an increased rates and a
  • 25:08greater proportion of children with
  • 25:11OCD compared to children without.
  • 25:14And this effect was particularly
  • 25:16marked for de Novo deletions.
  • 25:23And looking at some of the more
  • 25:26specific features of the de Novo CN BS
  • 25:29that we identified in our OCD sample,
  • 25:32a few things jump out.
  • 25:33The 1st is that a lot of these individuals
  • 25:37have Co occurring psychiatric disorder,
  • 25:41most notably Tourette's, which we know
  • 25:43goes along with OCD quite commonly.
  • 25:45So we did a secondary analysis
  • 25:48removing the individuals with the
  • 25:50Tourette's diagnosis and found
  • 25:52that the finding still holds.
  • 25:54The other thing to note is that
  • 25:57a lot most of the mutations,
  • 26:00the copy number variants that we
  • 26:04identified in individuals with OCD
  • 26:06are predicted to be pathogenic
  • 26:09or likely pathogenic,
  • 26:10meaning they're disrupting
  • 26:12or affecting gene products.
  • 26:15And this is in comparison to the
  • 26:18control samples where all the
  • 26:20CN VS that we identified were
  • 26:23not predicted to be pathogenic.
  • 26:25So that further suggests that
  • 26:27there may be some role for CN VS
  • 26:30that are predicted to be damaging
  • 26:32in the development of OCD.
  • 26:38So what we can say from this finding
  • 26:42is that de Novo rare, rare deletions,
  • 26:46but primarily de Novo deletions
  • 26:48are more common in children
  • 26:51with OCD compared to controls.
  • 26:53Most of the de Novo CN BS that
  • 26:56we identified in our sample are
  • 26:58predicted to be pathogenic.
  • 27:00And this suggests that de Novo CN
  • 27:03BS might play a role in the etiology
  • 27:07of OCD and we could use this to
  • 27:10help implicate new OCD risk genes.
  • 27:13This is a really robust approach
  • 27:16that at this point has identified
  • 27:19100 some risk genes and autism,
  • 27:22and we're hoping that it'll lead
  • 27:24to the identification of more risk
  • 27:27genes in OCD that could be potential
  • 27:29drug targets someday and help us
  • 27:31understand the biology of the disorder.
  • 27:36So I'd like to end by thanking everyone
  • 27:39who was involved in this research and
  • 27:43in my clinical and research training,
  • 27:46many of whom are are here in the audience.
  • 27:48So thank you for your support and
  • 27:51for funding sources for the award
  • 27:54committee and my wonderful colleagues.
  • 28:02Hello, my name is Jay.
  • 28:03I'm a PG I3 resident.
  • 28:05I'm sorry that I could
  • 28:06not be there in person.
  • 28:08I'm on my honeymoon now.
  • 28:09So so I'll try to be available for
  • 28:12questions after this presentation,
  • 28:14but I'm sorry that I cannot be
  • 28:16be there with you in person.
  • 28:18So my presentations on mental health
  • 28:21stigma by gender uncondition in
  • 28:24rural Uganda and I'm excited to
  • 28:26share with you our findings today.
  • 28:29So a little bit of background.
  • 28:31So mental illness are the leading
  • 28:34cause of disability globally and 80%
  • 28:36of those with mental illness reside
  • 28:38in no and middle income countries
  • 28:40as defined by the World Bank.
  • 28:43But most of like the resources
  • 28:44and most of the research done,
  • 28:46mental illness is done in high income
  • 28:49countries and a major factor in mental
  • 28:52illnesses are mental illness stigma.
  • 28:54So it's very prevalent globally and it,
  • 28:58you know,
  • 28:58it has many downstream effects
  • 29:00such as levels of funding
  • 29:01available for mental health care,
  • 29:03treatment seeking behaviors and
  • 29:06treatment outcomes as well.
  • 29:10So in terms of characterizing mental
  • 29:12illness stigma, as we all know,
  • 29:14mental illnesses can be very,
  • 29:16it can have very varying presentations.
  • 29:19It can be schizophrenia,
  • 29:20it can be anxiety,
  • 29:21it can be alcohol use disorder.
  • 29:23There's many different
  • 29:25types of mental illnesses.
  • 29:27So there have been studies in high income
  • 29:30countries characterizing, you know,
  • 29:32how people receive these different diverse,
  • 29:35you know, mental illnesses.
  • 29:37But there have not been so many studies
  • 29:40in low and middle income countries
  • 29:43characterizing the differences in how
  • 29:45people perceive these different conditions.
  • 29:48So in high income countries,
  • 29:49the research shows that those whose
  • 29:52symptoms align with gender based
  • 29:54stereotypes are more susceptible
  • 29:56to experiencing stigma.
  • 29:58But, you know,
  • 29:59those studies,
  • 29:59to our knowledge,
  • 30:01differentiate mental illness stigma by
  • 30:03gender or condition in low income countries,
  • 30:06to our knowledge.
  • 30:06And that's, and by gender,
  • 30:09you know, it means you know,
  • 30:10the gender of like the person that's
  • 30:13experiencing mental illness and the
  • 30:14gender of the person that's that's
  • 30:16evaluating or that's endorsing
  • 30:18stigmatizing attitudes towards
  • 30:19that person with mental illness.
  • 30:21So,
  • 30:22so both from both perspectives in
  • 30:25understanding how people perceive
  • 30:28these different mental illnesses
  • 30:30are very helpful because then
  • 30:33anti stigma interventions can
  • 30:35be designed accordingly to that.
  • 30:38So now I'm going to talk about
  • 30:40methods and you know,
  • 30:41I'm going to break this down step by step.
  • 30:44So first, you know,
  • 30:45we design some vignettes that describes
  • 30:47a person with a mental illness.
  • 30:49Then we randomly use random
  • 30:51sampling methods to select the
  • 30:52vignette to read a participant.
  • 30:54And then we administered a survey with
  • 30:58two with two with two parameters,
  • 31:02one's measuring proximal personal stigma
  • 31:04and another one measuring personal
  • 31:08stigma about the person in the vignette.
  • 31:12So for the vignette development,
  • 31:15for developing these vignettes,
  • 31:17we developed 4 vignettes illustrating
  • 31:19alcohol use disorder, anxiety disorder,
  • 31:22depression, and schizophrenia.
  • 31:24And we created both a male and
  • 31:26a female version of those,
  • 31:28so you know,
  • 31:31111 So each condition had two vignettes,
  • 31:331 depicting depicting a man with
  • 31:35a vignette and another depicting
  • 31:36a woman with a vignette.
  • 31:38In the vignettes,
  • 31:39depression and schizophrenia were
  • 31:41adapted from a study in Western
  • 31:43Uganda and vignettes and alcohol use
  • 31:46disorder and anxiety were developed
  • 31:48utilizing the SM5 criteria and and
  • 31:50having an intercultural team as I
  • 31:53was involved as well as Ugandan
  • 31:56collaborators as well to make sure
  • 31:59that it is adaptable and under and
  • 32:02understandable to the local context.
  • 32:05So this is where we did the study.
  • 32:07You can see Puyenda district is
  • 32:09highlighted in purple on the map.
  • 32:11This is by Lake Choga.
  • 32:12It's a very rural district.
  • 32:14It's got about four,
  • 32:15a little bit over 400,000 people.
  • 32:17It's also a very underserved area
  • 32:20of Uganda which is a low income
  • 32:23country and majority of population
  • 32:25are subsistence farmers.
  • 32:26There's 45% illiteracy rate above
  • 32:2918 years old.
  • 32:33So the study procedure,
  • 32:34so we selected 20 villages and three
  • 32:37sub counties in Vienna district.
  • 32:40Each sub county has about 50,000 people.
  • 32:42So we have a list of all the
  • 32:44villages in these three sub
  • 32:46counties and we utilize a number,
  • 32:48a random number generator to to pick
  • 32:50which villages we're going to do.
  • 32:52So each village is numbered
  • 32:54and we picked them randomly.
  • 32:55And then once we arrived at the village,
  • 32:58the community health workers have a
  • 33:00registry of all households in the village.
  • 33:03And so we again use the random number
  • 33:06generator to select households.
  • 33:08And once we selected a household,
  • 33:10we again use a random number
  • 33:12generator to select an adult,
  • 33:14defined as 18 years or above
  • 33:17in each household to interview.
  • 33:19And then once we arrived at the household,
  • 33:22we randomly selected the vignette.
  • 33:24So there are 8 possible choices
  • 33:27also with a random number generator
  • 33:30for each participant.
  • 33:32And this is a tool that we use
  • 33:34to measure the level of stigma
  • 33:36is adapted from a doctor Bob
  • 33:39Rosenhach studies SO2 batteries.
  • 33:41We're measuring a stigma and one
  • 33:43is personal acceptance Scale,
  • 33:45which measures proximal interpersonal stigma.
  • 33:48So what I mean by proximal personal
  • 33:51interpersonal stigma is, you know,
  • 33:53what would that person do?
  • 33:55So would that person be willing
  • 33:57to have somebody with mental
  • 33:59illness as a neighbor or not?
  • 34:01And then we have another scale,
  • 34:03which should be named a
  • 34:04broad acceptance scale,
  • 34:05which measures distal interpersonal stigma.
  • 34:08So that's more questions like
  • 34:09what should a society do about
  • 34:11this person with mental illness?
  • 34:16And so going into results.
  • 34:18So these are some descriptive statistics.
  • 34:20And you can see that we we got a pretty even
  • 34:23distribution across all four conditions.
  • 34:26And, and you know,
  • 34:28we have more females and males, but you know,
  • 34:32it's pretty evenly distributed otherwise.
  • 34:34And this is the results of the
  • 34:37personal Acceptance scale by condition,
  • 34:40gender of the vignette and
  • 34:41sex of the participant.
  • 34:43So higher numbers means greater
  • 34:45acceptance or less stigma.
  • 34:46So this measure is personal acceptance scale.
  • 34:49So so as you can see here,
  • 34:52you know, in yellow in the in
  • 34:54the bottom is schizophrenia.
  • 34:56You know, it's got lower acceptance
  • 34:58scores than let's say anxiety overall.
  • 35:00And you know,
  • 35:01you can also see some gender differences.
  • 35:04So, so filled in circles means
  • 35:07you know it's a female to female.
  • 35:10So you know,
  • 35:12both the person being depicted in
  • 35:14the vignette is female and the person
  • 35:16that is being read to is a female.
  • 35:18And hollow circles mean that the
  • 35:21person that's being detected is a
  • 35:23female or being depicted as female
  • 35:25and the person judging is a male.
  • 35:27And, you know,
  • 35:28likewise for and you can read
  • 35:30the legends to to describe the,
  • 35:33the the the rest.
  • 35:36And this is a broad acceptance
  • 35:37scale which had a, you know,
  • 35:39somewhat similar story,
  • 35:40although with less effect size
  • 35:43than personal acceptance scale.
  • 35:45So after accounting for multiple testing
  • 35:48and model this specification via permutation,
  • 35:51have you found significant differences in
  • 35:53levels of stigma among the four conditions?
  • 35:55For PAS, the P value is .00235
  • 35:59and BAS the P value is .04757.
  • 36:03So as you can see,
  • 36:05the PAS was more had a higher degree
  • 36:09of had a lower P value than the BAS.
  • 36:12And then we did a pairwise
  • 36:14secondary analysis and we found
  • 36:16that acceptance differed in among
  • 36:18anxiety and schizophrenia according
  • 36:19to PAS and BAS significantly.
  • 36:24So also we found some differences
  • 36:27in acceptances across gender.
  • 36:29So,
  • 36:30so one thing that we so the PAS
  • 36:35the varied across gender combinations
  • 36:37for depression with the empirical P
  • 36:40value of .017 and we can interpret this
  • 36:42result as a reflection of personal
  • 36:44acceptance being higher for women with
  • 36:47depression than men with depression.
  • 36:49If you refer back to our figure and
  • 36:51other specific gender effects were
  • 36:53not observed for any of the other
  • 36:56mental disorders in the PAS or for
  • 36:58any of the four disorders on the PAS.
  • 37:00So discussion so significant findings.
  • 37:03So we found significant differences in
  • 37:04the levels of acceptance for depression,
  • 37:07anxiety, alcohol use disorder,
  • 37:08and schizophrenia after adjusting for
  • 37:10the gender of the respondent and gender
  • 37:12of the individual depicted in vignette.
  • 37:14And schizophrenia was the least
  • 37:16accepted in pairwise comparisons.
  • 37:18After adjusting for multiple testing
  • 37:20found that people with anxiety
  • 37:21disorder appear to be more accepted
  • 37:24than people with schizophrenia and
  • 37:25women with depression were more
  • 37:27accepted than men with depression.
  • 37:29So compared to existing literature
  • 37:31may mean high income countries.
  • 37:33You know,
  • 37:34our studies backed up the finding that
  • 37:37schizophrenia has higher levels of stigma
  • 37:39and depression and anxiety predictably.
  • 37:41And but contrary to the existing literature
  • 37:43that finds the mental illnesses that are
  • 37:46more gender typical or more stigmatized,
  • 37:48we found the opposite.
  • 37:49Like for example,
  • 37:50men with depression were were more
  • 37:54stigmatized than women with depression.
  • 37:57And you know,
  • 37:58some other literature suggested
  • 38:00substance use disorders are more
  • 38:02stigmatized in mental illnesses.
  • 38:03So it's also possible that pair wise
  • 38:06comparisons between depression and
  • 38:08alcohol use disorder and between
  • 38:10depression and schizophrenia would
  • 38:11have demonstrated significant
  • 38:12differences with a larger sample without
  • 38:15the Bloemfair or any correction.
  • 38:17It did demonstrate significant differences.
  • 38:20So strengths of the study were that the
  • 38:22measurement of differential levels of
  • 38:24stigma based on specific mental illnesses,
  • 38:26adjusting for the gender of the
  • 38:27respondent and the gender of the
  • 38:29individual depicted in the vignette.
  • 38:31And this hasn't really been done
  • 38:33before in low income country setting.
  • 38:35And given the importance of
  • 38:37community and family support,
  • 38:39especially in low and
  • 38:40middle income countries,
  • 38:42on outcomes for mental illnesses,
  • 38:44the utilization of general population
  • 38:48sample is particularly important
  • 38:50in some weaknesses of the study.
  • 38:51Or that translations can lead
  • 38:53to subtle shifts in meaning,
  • 38:55possibly affecting the nature
  • 38:56of the responses elicited.
  • 38:58And you know,
  • 38:59it's also vulnerable to
  • 39:00social desirability bias,
  • 39:01like many surveys are so
  • 39:04meaning of the study.
  • 39:06Mental illness stigma is a major
  • 39:07barrier to treatment and access.
  • 39:09But most studies measuring mental
  • 39:11illness stigma do not differentiate among
  • 39:14different conditions and our study does.
  • 39:16And this also in our differential
  • 39:18findings also suggest that anti
  • 39:20stigma efforts need to be disorder
  • 39:23specific and gender specific.
  • 39:24And we hope that the static and form
  • 39:27the foundation for more targeted anti
  • 39:29stigma approaches for mental illness.
  • 39:31So there's some references and
  • 39:34some acknowledgements below,
  • 39:36and I'm happy to take any
  • 39:39questions that people have now.