Saliva May Help Diagnose PTSD in Veterans
As a bioinformatician and young veteran, Guy Shapira welcomed the opportunity to help with conducting a study to determine if saliva can reveal if war veterans have post-traumatic stress disorder, or PTSD.
The research team, which drew mostly from Tel Aviv University’s Sackler Faculty of Medicine and Sagol School of Neuroscience, collected saliva samples from approximately 200 veterans who suffered psychological trauma stemming from the years they spent fighting in the First Lebanon War in 1982. The researchers also characterized the participants’ psychological, social and medical conditions, including a detailed analysis of their microbiomes.
They found that the former soldiers with PTSD have a certain set of bacteria in their saliva, a distinct microbiotic signature that is believed to be the first biological marker for PTSD. The finding suggests that, in the future, saliva tests could be used to help identify this disorder. As of now, PTSD is often challenging to diagnose.
Shapira, a Ph.D. student at Tel Aviv University, was responsible for examining genetic and health-related data of the veterans who participated – information that had been compiled steadily over four decades. The veterans provided this data voluntarily, Shapira says, at least partly because the study carries important implications for their own psychological health.
The research was led by Illana Gozes, professor emerita of clinical biochemistry. “We looked at the bacteria in their blood and their saliva,” Gozes explains. To discover the microbial signatures, they analyzed the biometric data for each soldier individually and as a group. Comparing the results of the participants’ microbial distribution to the results of their psychological examinations and their responses to personal welfare questionnaires, the researchers learned that veterans with PTSD – and, more generally, those with significant mental health issues – have the same bacterial content in their saliva.
“Having empirical metrics to assess whether or not someone has PTSD can help veterans who make their case to the Army to get reparations,” Shapira says.
More research is required to support this finding, published in July in Nature’s prestigious Molecular Psychiatry, but it could have important implications for identifying people with PTSD. Currently, it can be diagnosed only through psychological and behavioral symptoms such as flashbacks, nightmares, sleep disorders, increased irritability and physical aggressiveness. Veterans sometimes don’t report these symptoms to health providers or realize they’re related to the trauma they experienced during combat.
The researchers also identified a correlation that indicates people with a higher level of education show a lower occurrence of the microbiotic signature linked to PTSD, while people who experienced greater exposure to air pollution show a higher occurrence of this signature. That confirms their finding that the veterans’ health is dependent on their individual biology combined with the conditions of their environment.
“Thanks to this study, it may be possible in the future to use objective molecular and biological characteristics to distinguish PTSD sufferers, taking into account environmental influences,” Gozes said in an article in Israel21c. “We hope that this new discovery and the microbial signatures described in this study might promote easier diagnosis of post-traumatic stress in soldiers so they can receive appropriate treatment.”
Gozes added that roughly a third of the subjects in their study hadn’t been diagnosed with PTSD previously. That meant they had never received any support from Israel’s Ministry of Defense or other officials for treatment and reparations, the payments to compensate for injuries sustained during war.
Shapira’s motivation to participate in this study is personal as well as professional: in addition to being veteran himself, his father served in the First Lebanon War. “Fortunately, he did not develop any PTSD, despite being shot in the foot...some of his friends died, so it wasn’t easy on him,” says Shapira.
“Having empirical metrics to assess whether or not someone has PTSD can help veterans who make their case to the Army to get reparations,” Shapira says. “It is a very difficult and demanding process, so the more empirical metrics we have to assess PTSD, the less people will have to suffer in these committees and unending examinations that are mostly pitched against the veterans because the state is trying to avoid spending too much money.”
Stronger psychedelics that rewire the brain, with Doug Drysdale
A promising development in science in recent years has been the use technology to optimize something natural. One-upping nature's wisdom isn't easy. In many cases, we haven't - and maybe we can't - figure it out. But today's episode features a fascinating example: using tech to optimize psychedelic mushrooms.
Listen on Apple | Listen on Spotify | Listen on Stitcher | Listen on Amazon | Listen on Google
These mushrooms have been used for religious, spiritual and medicinal purposes for thousands of years, but only in the past several decades have scientists brought psychedelics into the lab to enhance them and maximize their therapeutic value.
Today’s podcast guest, Doug Drysdale, is doing important work to lead this effort. Drysdale is the CEO of a company called Cybin that has figured out how to make psilocybin more potent, so it can be administered in smaller doses without side effects.
The natural form of psilocybin has been studied increasingly in the realm of mental health. Taking doses of these mushrooms appears to help people with anxiety and depression by spurring the development of connections in the brain, an example of neuroplasticity. The process basically shifts the adult brain from being fairly rigid like dried clay into a malleable substance like warm wax - the state of change that's constantly underway in the developing brains of children.
Neuroplasticity in adults seems to unlock some of our default ways of of thinking, the habitual thought patterns that’ve been associated with various mental health problems. Some promising research suggests that psilocybin causes a reset of sorts. It makes way for new, healthier thought patterns.
So what is Drysdale’s secret weapon to bring even more therapeutic value to psilocybin? It’s a process called deuteration. It focuses on the hydrogen atoms in psilocybin. These atoms are very light and don’t stick very well to carbon, which is another atom in psilocybin. As a result, our bodies can easily breaks down the bonds between the hydrogen and carbon atoms. For many people, that means psilocybin gets cleared from the body too quickly, before it can have a therapeutic benefit.
In deuteration, scientists do something simple but ingenious: they replace the hydrogen atoms with a molecule called deuterium. It’s twice as heavy as hydrogen and forms tighter bonds with the carbon. Because these pairs are so rock-steady, they slow down the rate at which psilocybin is metabolized, so it has more sustained effects on our brains.
Cybin isn’t Drysdale’s first go around at this - far from it. He has over 30 years of experience in the healthcare sector. During this time he’s raised around $4 billion of both public and private capital, and has been named Ernst and Young Entrepreneur of the Year. Before Cybin, he was the founding CEO of a pharmaceutical company called Alvogen, leading it from inception to around $500 million in revenues, across 35 countries. Drysdale has also been the head of mergers and acquisitions at Actavis Group, leading 15 corporate acquisitions across three continents.
In this episode, Drysdale walks us through the promising research of his current company, Cybin, and the different therapies he’s developing for anxiety and depression based not just on psilocybin but another psychedelic compound found in plants called DMT. He explains how they seem to have such powerful effects on the brain, as well as the potential for psychedelics to eventually support other use cases, including helping us strive toward higher levels of well-being. He goes on to discuss his views on mindfulness and lifestyle factors - such as optimal nutrition - that could help bring out hte best in psychedelics.
Show links:
Doug Drysdale full bio
Doug Drysdale twitter
Cybin website
Cybin development pipeline
Cybin's promising phase 2 research on depression
Johns Hopkins psychedelics research and psilocybin research
Mets owner Steve Cohen invests in psychedelic therapies
Doug Drysdale, CEO of Cybin
How the body's immune resilience affects our health and lifespan
Story by Big Think
It is a mystery why humans manifest vast differences in lifespan, health, and susceptibility to infectious diseases. However, a team of international scientists has revealed that the capacity to resist or recover from infections and inflammation (a trait they call “immune resilience”) is one of the major contributors to these differences.
Immune resilience involves controlling inflammation and preserving or rapidly restoring immune activity at any age, explained Weijing He, a study co-author. He and his colleagues discovered that people with the highest level of immune resilience were more likely to live longer, resist infection and recurrence of skin cancer, and survive COVID and sepsis.
Measuring immune resilience
The researchers measured immune resilience in two ways. The first is based on the relative quantities of two types of immune cells, CD4+ T cells and CD8+ T cells. CD4+ T cells coordinate the immune system’s response to pathogens and are often used to measure immune health (with higher levels typically suggesting a stronger immune system). However, in 2021, the researchers found that a low level of CD8+ T cells (which are responsible for killing damaged or infected cells) is also an important indicator of immune health. In fact, patients with high levels of CD4+ T cells and low levels of CD8+ T cells during SARS-CoV-2 and HIV infection were the least likely to develop severe COVID and AIDS.
Individuals with optimal levels of immune resilience were more likely to live longer.
In the same 2021 study, the researchers identified a second measure of immune resilience that involves two gene expression signatures correlated with an infected person’s risk of death. One of the signatures was linked to a higher risk of death; it includes genes related to inflammation — an essential process for jumpstarting the immune system but one that can cause considerable damage if left unbridled. The other signature was linked to a greater chance of survival; it includes genes related to keeping inflammation in check. These genes help the immune system mount a balanced immune response during infection and taper down the response after the threat is gone. The researchers found that participants who expressed the optimal combination of genes lived longer.
Immune resilience and longevity
The researchers assessed levels of immune resilience in nearly 50,000 participants of different ages and with various types of challenges to their immune systems, including acute infections, chronic diseases, and cancers. Their evaluation demonstrated that individuals with optimal levels of immune resilience were more likely to live longer, resist HIV and influenza infections, resist recurrence of skin cancer after kidney transplant, survive COVID infection, and survive sepsis.
However, a person’s immune resilience fluctuates all the time. Study participants who had optimal immune resilience before common symptomatic viral infections like a cold or the flu experienced a shift in their gene expression to poor immune resilience within 48 hours of symptom onset. As these people recovered from their infection, many gradually returned to the more favorable gene expression levels they had before. However, nearly 30% who once had optimal immune resilience did not fully regain that survival-associated profile by the end of the cold and flu season, even though they had recovered from their illness.
Intriguingly, some people who are 90+ years old still have optimal immune resilience, suggesting that these individuals’ immune systems have an exceptional capacity to control inflammation and rapidly restore proper immune balance.
This could suggest that the recovery phase varies among people and diseases. For example, young female sex workers who had many clients and did not use condoms — and thus were repeatedly exposed to sexually transmitted pathogens — had very low immune resilience. However, most of the sex workers who began reducing their exposure to sexually transmitted pathogens by using condoms and decreasing their number of sex partners experienced an improvement in immune resilience over the next 10 years.
Immune resilience and aging
The researchers found that the proportion of people with optimal immune resilience tended to be highest among the young and lowest among the elderly. The researchers suggest that, as people age, they are exposed to increasingly more health conditions (acute infections, chronic diseases, cancers, etc.) which challenge their immune systems to undergo a “respond-and-recover” cycle. During the response phase, CD8+ T cells and inflammatory gene expression increase, and during the recovery phase, they go back down.
However, over a lifetime of repeated challenges, the immune system is slower to recover, altering a person’s immune resilience. Intriguingly, some people who are 90+ years old still have optimal immune resilience, suggesting that these individuals’ immune systems have an exceptional capacity to control inflammation and rapidly restore proper immune balance despite the many respond-and-recover cycles that their immune systems have faced.
Public health ramifications could be significant. Immune cell and gene expression profile assessments are relatively simple to conduct, and being able to determine a person’s immune resilience can help identify whether someone is at greater risk for developing diseases, how they will respond to treatment, and whether, as well as to what extent, they will recover.