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Posts Tagged ‘mental illness’


Socioeconomic factors involved in chronic illness

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

I have discussed a number of features of the health care system that are available to individuals and are becoming integrated over the last decade to a much greater extent than at the end of the last century.
Part of this has come because of an emergent view of health care markets and the patient base as a customer patient base.  Related to this view is the emergence over a quarter of a century of greater consolidation of heath care providers.  The first significant attempt to rationalize healthcare payments was with the development of diagnostic related groups by studies and proposals at Yale University School of Management under Robert Fetter. The first implementation was in New Jersey, prematurely supported by the Healthcare Financing Administration. As healthcare financing is usually predicated on HCFA, the insurance agencies, which includes negotiated for-profit entities follow suit.  However, it takes a large patient base to support any insurance provider, and with the not-for profit providers negotiating with large for-profit organizations, there is a tension and a balance that has to come with such a plan.  The existing system doesn’t support a fully nationalized system as exists elsewhere, and a two tiered system is almost inevitable.  In addition, our society, built by two centuries of immigration, and having a model system from the Kaiser Project in building the San Francisco bridge, that also influence IBM, employment-based insurance had a good start.  Government provision had to wait, with real success in the mid-twentieth century.

I have pointed out that the healthcare system has been in a remodeling process for the last quarter of a century aligned very much with business interests and the workforce. Even retirement insurance has been a worker innovation.  However, what is the underlying situation that arises from this arrangement.
The power of labor-unions has been eroded, which erodes an element of leverage.

At the beginning of the industrial revolution in England there was a seminal study that showed that the workers developed stress related illness that was not seen at the management level. In the US we have had streams of immigration and seemingly boundless innovation that has contributed to an impressive economic image of a country.  However, the story is also bimodal.  There is a strong cultural factor and family structure factor in both upward mobility and in resilience of the individual under stress.  This has been evident from observing the emergence of a former slavery descendent negro population and suppression of this people for a half century after the civil war, and more recently from migrations from Mexico, South America, and Cuba.  We have had a selective migration of educated people from India and Asia, being that they were of a more mobile class of achievers.  America, the home of the brave has been limited in representation.

What are the effects of this class disequilibrium?  As the country has growth and as companies have moved offshore for cheap labor, the power of labor declined, and the benefits of labor have been pushed down.  This resulted in a decline of the middle class, and levels of poverty and over the poverty line pushing families into considerable tension.  This is characterized by high divorce rates, and there are single mothers working two shifts, or both parents trying to balance the time available.

The problem here is like a compound fractured society.  The clustered neighborhoods are not just black, as a generation moved out and up, and property values dropped in once desirable neighborhoods.  The existence of a close community of common culture is workable as it is held together by common lineage. However, the fissures occur where the parents have no time for family, and the parents have no time to play with or read to their children.  This problem can be carried over from one generation to the next by failure in child development to gain basic living and society skills.  What we don’t happen to recognize is that as this multiplies, compounded by the highest level of incarceration in the Western world, there is uncontrolled violence, hatred, suicide, anger, and shortened lifespan.  This has a huge cost, and the cost weighs on the individuals affected and the communities they live in.  The cost includes the health burden.  Moreover, even though we have a large service sector with sports and exercise therapy, it may not be included in healthcare benefits, but is provided as add on to unreimbursed costs.

 

 

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An ambiguous course of psychosis

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

It is not always clear what the diagnosis is when a young person develops a psychosis, which is usually a clear break, but the features are not typical.  In the New York Times Opinion Page of Nov 17, 2015, Norman Ornstein describes the development of such in his son – How to help save the mentally ill from themselves.  He describes legislation in process to deal with the problem of when you institutionalize a potentially suicidal patient.  This was the situation that I described in the murder of Rabbi Adler on the podium by Richard Wishnetsky so many years ago.  In the case of Ornstein, his oldest son Mathhew died at 34 of carbon monoxide poisoning 10 years after his problem was discovered.

The son was a brilliant student, and he excelled in debating.  He was compassionate and empathetic.  This young man was a standup comedian and after graduating from Princeton wh went to Hollywood. The father describes his son’s condition as anosognosia, meaning lack of recognition of his illness.  I recall that a prominent cancer surgeon who was manic depressive psychotic and required lithium might have behaved that way when he failed to take his medication. He had a tragic surgical failure that ended his career when he was doing a rectal dissection and got into the posterior vascular bed and was in trouble, needing the assistance of the Chief of Urology.  The patient who died received over 100 units of blood. This very intelligent surgeon would throw the specimen he removed to the pathologist who entered the operating room in poor judgement.  I also recall a valued colleague of mine, a mathematical genius with MD and PhD tell me how the great surgeon and father of kidney transplantation could work tirelessly, but he died in a plane crash – himself as the pilot. I’m not in a position to disagree with Norman Ornstein’s conclusion that the son had a serious mood disorder, but the presentation he describes is similar to the two cases I mention.  In addition, I did not mention that my dear colleague was himself manic depressive, and he would work tirelessly, except when he was down and out.  He wrote an incredible program to diagnose heart attach from the serum enzymes for the IBM PC-XT in apl.  He sailed through difficult mathematics classes without taking notes.  He bacame interested in Shannon Information Theory when he heard a lecture by a microbiologist colleague who had done seminal work in classifying organisms by their biochemical features, which led to extending the use of feature extraction and combinatorial classes.

Ornstein points out that his son was over age 18, so that neither the family or professionals had any legal authority to make a decision about his hospitalization or related matters.  This is not quite like what I had seen with my brother.  But in my brother’s case, he was completely fractured, but he also was in no way belligerent.  In the case of Mathew Ornstein, he was never belligerent, but he was unkempt, kept himself poorly, and grew a beard.  He also becaame ultra religious.  The religiosity was also a feature of my own brother’s illness.  Matthew took a position that he could not take medication.  What is not clear is what medication he would have been on, which might be informative.

see more at – http://www.nytimes.com/2015/11/17/opinion/how-to-help-save-the-mentally-ill-from-themselves

 

 

 

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To reduce symptoms of mental illness and retrain the brain

Larry H. Bernstein, MD, FCAP, Curator

Leaders in Pharmaceutical Intelligence

Series E. 2; 5.11

Researchers have found that by specifically targeting a central signaling pathway in the brain, they can improve the innate behavioral response to stress in mice. Stress-induced behaviors in rodents reflect many of the symptoms that affect people suffering from major depression and other clinical conditions associated with stress. The findings, published July 20th online in the journalNature Neuroscience, suggest a new strategy for treating depression and other stress-associated disorders.

The study was led by James A. Bibb, Ph.D., at The University of Texas Southwestern Medical Center, who received NARSAD Young Investigator grants in 2000 and 2003, and lead authorFlorian Plattner, Ph.D. The scientific team also included Paul Greengard, Ph.D., a member of BBRF’s Scientific Council and a 1992, 2002, and 2008 Distinguished Investigator; Eric J. Nestler, M.D., Ph.D., a Scientific Council Member and a 1996 Distinguished Investigator; 2006 Young Investigator Kanehiro Hayashi, Ph.D.; 2007 Young Investigator Eunice Y. Yuen, Ph.D.; 1999 and 2004 Young Investigator Zhen Yan, Ph.D.; and 1999 Independent Investigator and 2006 Distinguished Investigator Angus C. Nairn, Ph.D.

The team’s findings are a result of a detailed investigation into a “signaling cascade,” called the cAMP/PKA pathway, which regulates a wide range of processes in the central nervous system. Disruption of the pathway has been linked with several mental disorders, including depression. Some existing antidepressant medications are known to boost cAMP signaling, but better understanding how this signaling network works could help researchers develop treatments that are more effective or cause fewer side effects.

Two new small-molecule compounds tested in mice can alleviate some symptoms of schizophrenia-like behaviors, including movement abnormalities, social avoidance, and cognitive performance. As reported in the July 1st issue of Neuropsychopharmacology, these research results may point the way toward new kinds of medications that treat specific aspects ofschizophrenia behaviors.

Current antipsychotic drugs used to treat the disorder target the dopamine D2 receptor, an important communication port for some neurons in the brain. These drugs are used primarily to treat schizophrenia “positive” symptoms such as delusions and hallucinations. They are less effective in treating “negative” symptoms such as a lack of pleasure in everyday life, or concentration and memory problems (“cognitive symptoms”), according to Duke University Medical Center scientists William C. Wetsel, Ph.D., a 1998 NARSAD Independent Investigator grantee, and Marc G. Caron, Ph.D., a Foundation Scientific Council member and 2005 NARSAD Distinguished Investigator grantee.

Current antipsychotic drugs were developed to bind to and block one specific type of communication pathway through dopamine D2 receptors, but the receptors are involved in more than one type of signaling pathway. Dr. Wetsel and colleagues decided to look for drug candidates that would block other pathways related to the dopamine D2 receptor, in the hope that this might reveal novel ways to treat a wider variety of schizophrenia symptoms.

They tested two dopamine D2 receptor-targeting compounds called UNC9975 and UNC9994 (developed by Jian Jin, Ph.D., of the University of North Carolina) that influence the beta-arrestin communication pathway, a different pathway than the one typically affected by antipsychotic drugs. The researchers showed that the compounds could normalize schizophrenia-like symptoms in mice by reducing their hyperactive movements, improving their memory for novel stimuli, and making them more social around other mice, among other improvements.

The new compounds also produced a much lower level of catalepsy—the rigid muscle, “trance-like” state that is sometimes a side effect of schizophrenic treatment—than traditional antipsychotic drugs such as haloperidol. Targeting different pathways connected to the dopamine D2 receptors, the researchers say, may increase the possibilities for treating people with schizophrenia in more individualized, fine-tuned ways that match their exact symptoms and vulnerabilities to side effects.

Effects of β-Arrestin-Biased Dopamine D2 Receptor Ligands on Schizophrenia-Like Behavior in Hypoglutamatergic Mice

Su M Park1, Meng Chen1, Claire M Schmerberg1, Russell S Dulman1, Ramona M Rodriguiz1,2, Marc G Caron3, Jian Jin4 and William C Wetsel1,2,3,5
Neuropsychopharmacology 2015; http://dx.doi.org:/10.1038/npp.2015.196

Current antipsychotic drugs (APDs) show efficacy with positive symptoms, but are limited in treating negative or cognitive features of schizophrenia. Whereas all currently FDA-approved medications target primarily the dopamine D2 receptor (D2R) to inhibit Gi/o-mediated adenylyl cyclase, a recent study has shown that many APDs affect not only Gi/o– but they can also influence β-arrestin- (βArr)-mediated signaling. The ability of ligands to differentially affect signaling through these pathways is termed functional selectivity. We have developed ligands that are devoid of D2R-mediated Gi/o protein signaling, but are simultaneously partial agonists for D2R/βArr interactions. The purpose of this study was to test the effectiveness of UNC9975 or UNC9994 on schizophrenia-like behaviors in phencyclidine-treated or NR1-knockdown hypoglutamatergic mice. We have found the UNC compounds reduce hyperlocomotion in the open field, restore PPI, improve novel object recognition memory, partially normalize social behavior, decrease conditioned avoidance responding, and elicit a much lower level of catalepsy than haloperidol. These preclinical results suggest that exploitation of functional selectivity may provide unique opportunities to develop drugs with fewer side effects, greater therapeutic selectivity, and enhanced efficacy for treating schizophrenia and related conditions than medications that are currently available.

The estrogen-related drug raloxifene can improve attention and memory in men and women with schizophrenia, according to a new study published in the journal Molecular Psychiatry.

University of New South Wales researcher Cynthia S. Weickert, Ph.D., a 1999 and 2001 NARSAD Young Investigator and 2004 Independent Investigator grantee, and her colleagues say their raloxifene findings could help improve some cognitive problems related to schizophrenia that have been the most difficult to treat with drugs. Dr. Weickert’s research team included NARSAD Young Investigator grantees Rhoshel K. Lenroot, M.D., (2003), and Ans Vercammen, Ph.D., (2010), along with Independent Investigator grantee Jayashri Kulkarni, Ph.D., (2000), and her husband and first author Tom Weickert, Ph.D.

A growing body of evidence suggests that estrogen plays a beneficial role in the brain, supporting growth and protecting neurons from damage. From work supported by her NARSAD Young Investigator awards, Dr. Weickert and her colleagues found that brain estrogen receptors are altered in some people with schizophrenia, blunting their ability to respond to estrogen’s beneficial effects. Raloxifene stimulates estrogen receptors and can help overcome a blunted estrogen response. Raloxifene is probably best known as a treatment for osteoporosis in women, where it mimics estrogen’s beneficial action in bones. The drug also stimulates estrogen receptors in the brain and may guard against memory loss in aging, making it potentially useful for cognitive problems in schizophrenia patients.

The research team examined the drug’s effect in 98 people diagnosed with schizophrenia or schizoaffective disorder (which combines symptoms of schizophrenia and depression). All of the patients received a daily dose of raloxifene along with their usual antipsychotic medications in one phase of the clinical trial and a placebo in another phase.

After the first six-week period, patients taking raloxifene had improved scores on memory and attention, compared to those taking placebo. When considering all the people in the study during both phases, raloxifene treatment significantly improved attention and thought processing speed. Raloxifene didn’t reduce the severity of schizophrenia symptoms more than the placebo did, but both groups showed less symptoms overall during the study, and none of the patients had severe side effects from the treatment.

Dr. Weickert and colleagues did detect some signs that the positive impact of raloxifene lasted more than one month after the treatment stopped. Although the researchers do not know the exact reasons for the lasting effects, they note that stimulating estrogen receptors might protect neurons, reduce inflammation, and increase connections between nerve cells in the brain over a longer time frame than drugs working on other neurotransmitter receptors. In light of their findings, they suggest future studies should replicate these results in a larger group of schizophrenia patients and also determine how long the cognitive benefits of a six-week treatment with raloxifene may last.

An injectable antipsychotic medication whose effects last for three months has successfully delayed the return of schizophrenia symptoms, researchers have found. Taking the drug in this form may help people with schizophrenia who struggle to stay on treatment by enabling them to take medication less frequently.

The research team, which included Adam J. Savitz, M.D., Ph.D., recipient of a NARSAD Young Investigator Grant in 2001, examined use of the long-acting antipsychotic medication paliperidone palmitate (Invega) in treating symptoms of schizophrenia such as hallucinations, delusions, and strong feelings of suspicion. The research was published online March 29th inJAMA Psychiatry.

When a person with schizophrenia cannot maintain a daily medication schedule, the drug level in his or her body can dip too low to combat symptoms, leading to relapse (return of symptoms) and an increased risk of being hospitalized. This study aimed to determine whether a dosage that would only have to be taken once every three months, rather than every day, would effectively hold off symptoms. After starting with a once-monthly dosage, patients took a three-month dosage to maintain symptom prevention and then were given randomly either placebo or the same three-month dosage every 12 weeks to see whether the medication’s positive effects would persist. (A placebo is a look-alike with inactive ingredients.)

Significantly fewer people who got the second three-month dosage experienced symptom relapse during the experimental phase of the study, compared to those taking a placebo. During this phase, the placebo group also reported more severe symptoms, while the paliperidone palmitate group’s symptoms remained constant.

The two groups also showed different patterns of side effects. The more serious side effects occurred in the placebo group: anxiety and return of other symptoms of schizophrenia. The paliperidone palmitate group more frequently experienced headaches, weight gain, common colds, as well as so-called extrapyramidal symptoms, which involve disruptions to movement.

This study did not include people with a history of substance dependence, major active medical problems, or other serious mental disorders. More research is needed to know whether less frequent dosage of long-acting injectable medication like paliperidone palmitate can help prevent relapse in these groups.

Efficacy and Safety of the 3-Month Formulation of Paliperidone Palmitate vs Placebo for Relapse Prevention of Schizophrenia – A Randomized Clinical Trial

Joris Berwaerts, MD1; Yanning Liu, MS2; Srihari Gopal, MD, MHS1; Isaac Nuamah, PhD1; Haiyan Xu, PhD1; Adam Savitz, MD, PhD1; Danielle Coppola, MD1; Alain Schotte, PhD3; Bart Remmerie, Chem Eng3; Nataliya Maruta, MD, PhD4; David W. Hough, MD1
JAMA Psychiatry. 2015; 72(8):830-839. http://dx.doi.org:/10.1001/jamapsychiatry.2015.0241.

Design, Setting, and Participants  This randomized, multicenter trial conducted from April 26, 2012, through April 9, 2014, in 8 countries consisted of 4 phases: 3-week screening phase, flexible-dose 17-week open-label transition phase, 12-week open-label maintenance phase, and open-ended double-blind (DB) phase. Of the 506 patients enrolled (aged 18-70 years; DSM-IV-TR diagnosis of schizophrenia), 305 were randomized to 3-month paliperidone palmitate (n = 160) or placebo (n = 145) in the DB phase.

Interventions  Patients received once-monthly doses of the 1-month formulation of paliperidone palmitate (50, 75, 100, or 150 mg eq) during the transition phase, followed by a single dose of the 3-month formulation (3.5 times the stabilized dose of once-monthly paliperidone palmitate) during the maintenance phase. Stabilized patients were randomized to receive either a fixed dose of 3-month paliperidone palmitate (175, 263, 350, or 525 mg eq) or placebo once every 3 months during the DB phase.

Main Outcomes and Measures  Time from randomization to the first relapse event (time to relapse) in the DB phase.

Results  In the interim analysis, time to first relapse was significantly different in favor of the paliperidone palmitate group vs the placebo group (hazard ratio = 3.45; 95% CI, 1.73-6.88; P < .001); median time to relapse was 274 days for placebo but not estimable for 3-month paliperidone palmitate. An independent data monitoring committee recommended early study termination due to efficacy. In the DB phase, 183 of 305 patients (62% with 3-month paliperidone palmitate; 58% with placebo) had at least 1 treatment-emergent adverse event; those noted more frequently in the group receiving paliperidone palmitate than in the placebo group were headache (9% vs 4%), weight increased (9% vs 3%), nasopharyngitis (6% vs 1%), and akathisia (4% vs 1%).

Conclusions and Relevance  Compared with placebo, the 3-month formulation of paliperidone palmitate administered 4 times yearly significantly delayed time to relapse in patients with schizophrenia. The 3-month formulation was generally tolerable and has a safety profile consistent with other marketed paliperidone formulations.

Trial Registration  clinicaltrials.gov Identifier:NCT01529515

 

Tracking Down the Causes of Alzheimer’s

University of Basel
http://www.biosciencetechnology.com/news/2015/09/tracking-down-causes-alzheimers?et_cid=4792750&et_rid=535648082&location=top

 

Researchers from the University of Basel were able to show that memory function (image shows the hippocampus highlighted) depends on calcium-regulating genes. (Source: MCN University of Basel

http://www.biosciencetechnology.com/sites/biosciencetechnology.com/files/bt1509_basel_brain.jpg

Genes are not only important for regular memory performance, but also for the development of Alzheimer’s disease. Researchers at the University of Basel now identified a specific group of genes that plays a central role in both processes. This group of molecules controls the concentration of calcium ions inside the cell. Their results appear in the current issue of the journal JAMA Psychiatry.

Intact memory capacity is crucial for everyday life. This fact becomes apparent once a memory disorder has developed. Alzheimer’s disease is the most common cause of age-associated memory disorders. Due to increasing life expectancy, the disease is on the rise in Switzerland and worldwide. Unfortunately, there is no effective treatment to cure or even slow down Alzheimer’s yet. Thus, understanding the origins of this neurodegenerative disorder is key to the development of much needed treatments.

Scientists have known for some years now, that genes do not only play a crucial role in normal memory performance, but also in the development of Alzheimer’s. However, it was so far unclear if specific genes are involved in both these processes.

Researchers at the transfaculty research platform at the Psychiatric University Clinics Basel and the Faculty of Psychology at the University of Basel were now able to show in a large scale study that a specific group of genes controls several processes that are central for regular brain functions as well as for the development of Alzheimer. First author Dr. Angela Heck collected and analyzed data of over 57,000 participants for this study.

Calcium is crucial

The study identified genes responsible for the concentration of calcium ions in the cell as central players of physiological and disease processes in the brain. Calcium genes stand in mutual relationship with memory performance of young and older healthy adults as well as with the function of the hippocampus, a brain region that is central to intact memory. Furthermore, calcium genes correlate with the risk for Alzheimer disease. The results contribute to the understanding of the complex processes that lead to memory disorders, such as Alzheimer’s.

 

 

 

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To understand what happens in the brain to cause mental illness

Larry H Bernstein, MD, FCAP, Curator

Leaders in Pharmaceutical Intelligence

Series E. 2; 5.10

https://bbrfoundation.org/research/basic-research

Fernando Sampaio Goes, M.D., a 2008 NARSAD Young Investigator at Johns Hopkins School of Medicine, and his colleagues took an alternative approach to the ongoing genome-wide association studies (GWAS) that hunt for these factors by scouring the complete genomes of tens of thousands of individuals. The team––which included 2005 Young InvestigatorDimitrios Avramopoulos, M.D., Ph.D.; 2000 Young Investigator, 2008 Independent Investigator, and BBRF Scientific Council member James B. Potash, M.D., M.P.H.; and 2004 Young Investigator Peter P. Zandi, Ph.D.––conceived the study to detect rare genetic variations that GWAS are not designed to find.

Rather than scanning entire genomes for depression-associated variations, Goes’s team narrowed its search to a set of genes in which they already suspected alterations might contribute to depression: those that encode proteins found at or near the junctions between neurons, where cell-to-cell communication takes place. Based on previous surveys of these synaptic proteins, the scientists chose 1,742 genes to include in their analysis.

They compared the protein-coding sequences of that set of genes in 259 people with major depression to the same set in 334 unaffected individuals. To increase the chance of finding relevant genetic factors, all the patients with depression were selected based on the criterion of early-onset, recurrent depression, which is suspected by some to be a more heritable form of the illness. (An important component of depression causation is environmental, and reflects the particular life circumstances of those affected, who may or may not be naturally resilient when faced with stress and other environmental factors.)

The team’s analysis pointed to two sets of genes in which variations were linked with major depression. One includes genes that control the growth of dendritic spines (tiny knob-like protrusions from a neuron’s surface that receive inputs from other neurons). Other research has suggested that the size, density, and shape of these structures may be involved in mood disorders and other mental illnesses. The second gene set includes genes linked with the entry of calcium into neurons, which regulates a variety of processes, including the release of message-propagating neurotransmitters. Variations within this gene set have also been linked to autism and epilepsy.

Researchers have identified unique characteristics of emotional processing in young people with post-traumatic stress disorder (PTSD), showing for the first time how that processing might be disrupted at different ages.

Publishing their findings online August 5th in Neuropsychopharmacology, were 2012 NARSAD Young Investigator grantee Ryan J. Herringa, M.D., Ph.D., of the University of Wisconsin School of Medicine and Public Health and Richard C. Wolf, a Ph.D. candidate at the university. Together they  looked at brain activity during an emotion-related task in children aged 8 to 18, both with and without PTSD. The children with PTSD had experienced trauma such as sexual abuse, the death of a loved one, a physical accident, or witnessing violence.

The children viewed emotionally “threatening” and “neutral” pictures. During this task, the researchers used imaging to measure activity in brain regions associated in PTSD with an increased fear response and sense of threat. These regions include the amygdala, important for processing emotions; the dorsal anterior cingulate cortex (dACC), which helps to gauge threat levels; and the medial portion of the prefrontal cortex (PFC), crucial for dialing back fear responses and putting perceived threats in context.

The researchers found higher threat-related dACC activity in youths with PTSD, as well as weaker connections between the amygdala and mPFC. The findings suggest these brain regions contribute to the difficulty young people with PTSD have in assessing perceptions of threat.  The study also found that amygdala-PFC connections followed a different developmental path for youths with PTSD. Whereas those connections were stronger at older ages in those without PTSD, the same connections grew weaker for children with PTSD as they aged. This may reflect a progressive weakening in the ability of the PFC to reduce fear.

In research reported June 17th in the journal Neuron, scientists have shown that a protein called CPEB3 is critical for the stabilization and storage of long-term memories in mice. Three-timeNARSAD Distinguished Investigator and BBRF Scientific Council member Eric Kandel, M.D., led the research. Also on the team is 2013 NARSAD Young Investigator Pierre Trifilieff, Ph.D.

CPEB3 is a “prion-like” protein. Prions––infectious, misshapen proteins best known for the devastation they cause––clump together and lead to brain damage in people and animals with mad cow disease and related conditions. Similar protein-clumping mechanisms may also contribute to neurodegenerative diseases including Alzheimer’sParkinson’s, and amyotrophic lateral sclerosis. (Curiously, certain proteins with prion-like properties have an important role in the healthy brain.)

The new finding extends previous work showing that prion-like proteins are vital for the stabilization of long-term term memory in sea slugs and fruit flies. Although further work is needed to understand whether the same mechanism is at work in humans, humans do produce a protein similar to the mouse protein CPEB3.

Memories are stored in the connections between neurons, and proteins play a role in the long-term storage of the information. But since proteins degrade over time, scientists had wondered how a memory can persist long after a new experience triggers neurons to make memory-specific proteins. Prion-like proteins, which are self-perpetuating because they can convert normal proteins to their own misshapen form, appear to be the answer.

Genetic studies have recently yielded large numbers of “hits” for genes that subtly increase or decrease risk for disorders, including for schizophrenia. However, there have been no hits for major depression, perhaps because the studies are not yet large enough or because depression is less heritable. Estimates put the heritability of major depression at around 50%, with the remaining contribution coming from environmental and experiential causes.

However, a new approach has paid off: a study published online July 15th at the journal Natureidentifies two genomic regions that harbor genes that increase risk of major depression. A multinational collaboration employed a strategy of narrowing the pool of subjects to women in China with the most severe and stubborn form of depression, with the hope that a more homogenous population would yield results.

In an accompanying News and Views, 2014 Lieber Prizewinner for Outstanding Achievement in Schizophrenia Research,Patrick Sullivan, M.D., of the University of North Carolina, writes, “This first identification of replicable, significant genome-wide associations for MDD is exceptional.”

Qi Xu, Ph.D., of Peking Union Medical College and Jun Wang, Ph.D., of BGI-Shenzhen, who led the China components of the study, along with Foundation Scientific Council Member Kenneth Kendler, M.D., of Virginia Commonwealth University and 2007 NARSAD Distinguished Investigator Grantee Jonathan Flint, M.D., of the University of Oxford in the United Kingdom focused exclusively on women with severe, recurrent depression (an average of more than five episodes), building a sample of 5,303 cases and 5,337 controls. The results were replicated in a separate group of 3,231 Chinese women with major depression and 3,186 mixed male/female controls.

“I think this paper is groundbreaking because it really demonstrates that we can make progress in reducing genetic heterogeneity by paying attention to key clinical indicators,” said three-time NARSAD Grantee, Francis McMahon, M.D., of the National Institute of Mental Health (NIMH), who was not an author on the paper.

A team based at the University of Edinburgh analyzed data from thousands of Scottish adults to see whether they had genetic mutations either linked with obesity or major depressive disorder. They tested for relationships between those genetic profiles, the presence of depression or other psychological distress, and body mass index, a measure used to determine obesity. A genetic predisposition for obesity more strongly predicted actual obesity among those adults who were also depressed.

The findings were reported June 30th in Translational Psychiatry by a team including 2008NARSAD Distinguished Investigator Grantee David J. Porteous, Ph.D., and 2010 Independent Investigator Andrew M. McIntosh, Ph.D.

The study results show people becoming obese in part because of their depression, rather than becoming depressed because they are already obese. The experience of depression may drive disordered eating habits. It may also trigger chemical responses in the body (such as the release of the stress hormone cortisol) that promote weight gain, the researchers hypothesize.

The team also found some degree of association between a genetic profile linked to obesity and current psychological distress, even among individuals who were not obese. Obesity-linked genes also more closely predicted actual obesity among people experiencing distress even if they were not diagnosed with depression. This indicates that psychological strain, and not just depression per se, contributes to obesity.

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