Friday, July 25, 2025

Ketamine could treat depression by interacting with the brain’s ‘opioid system’

King's College London

Ketamine is a highly effective, fast-acting antidepressant that works even for patients who have not responded to other medications. However, the brain mechanisms important for these rapid treatment effects are yet to be determined.

Researchers at King’s College London, who are investigating why ketamine could be a good treatment for some people with depression, have discovered that the drug’s antidepressant effects involve the brain’s opioid system.

The study, led by King’s College London and published in Nature Medicine, included 26 individuals with clinically diagnosed depression who were given a low dose ketamine infusion across two sessions during neuroimaging.

Before receiving the ketamine infusion, in one session they were given naltrexone, which blocks the opioid receptors in the brain, and in the other they were given a placebo.

Participants were monitored during the infusion in a brain scanner using a method called magnetic resonance spectroscopy (MRS). MRS measured dynamic changes in a brain chemical called glutamate. Depressive symptoms were then assessed using the clinician-rated Montgomery-Åsberg Depression Rating Scale (MADRS) 24-hours after infusion, when ketamine’s antidepressive symptoms peak.

They found that blocking the opioid system reduced both the brain’s glutamatergic response and the antidepressant effects observed the following day, suggesting that the opioid system plays a key role in mediating the antidepressant response.

The study also identified a sex-related effect: the effect of naltrexone on glutamatergic activity appeared more pronounced in males with depression than in the females with depression.

These insights into how ketamine works for different people is essential to personalising treatments.

Dr Luke Jelen, lead author of the study and a Clinical Lecturer in Psychiatry at King’s College London, said: “Ketamine often makes the news for negative reasons. However, at a low dose, ketamine shows enormous potential to offer relief from the symptoms of depression.”

“Understanding whether the opioid system is involved ketamine’s antidepressant effects is a really important question, given how much we still don't know about how ketamine works. “Our study shows that the opioid system is involved and offers insight into how it contributes to ketamine’s effects.”

The authors are keen to highlight that ketamine is not classified as an opioid and does not bind to opioid receptors with high affinity like morphine or heroin. Instead, the findings point to a dynamic interplay between the glutamatergic and opioid systems, which may work together to support ketamine’s rapid antidepressant effects.

Opiates can offer relief from the systems of depression however they are highly addictive. Understanding if and how the opioid system is involved in the effects of ketamine is important to understand why ketamine works and develop new, alternative treatments.

Low-dose ketamine is currently being used to treat depression in private clinics and a small number of NHS clinics. At higher doses it is also used in medicinal anaesthesia. However, it is also used recreationally and if misused can cause serious health problems including irreversible damage to the bladder and kidneys.

Professor Mitul Mehta, a professor of neuroimaging & psychopharmacology at King’s College London, said: “The brain’s different neurochemical systems work together to produce our experiences and behaviour so it is no surprise that the opiate system may have a role in ketamine’s antidepressant effect.”

“We need these kinds of studies to understand exactly what the important brain mechanisms are for antidepressant effects. Understanding more about how ketamine works can lead to treatment being personalised for different people, which is vital for creating safe and effective treatments."

ENDS

Notes to editor:

If you would like to speak to the researchers involved in this study, please email Jo Dungate at the King’s College London press office at joanna.dungate@kcl.ac.uk.

About King’s College London

King’s College London is amongst the top 40 universities in the world and 5th best in the UK (QS World University Rankings 2026), and one of England’s oldest and most prestigious universities.  With an outstanding reputation for world-class teaching and cutting-edge research, King’s maintained its sixth position for ‘research power’ in the UK (2021 Research Excellence Framework).  

King's has more than 33,000 students (including more than 12,800 postgraduates) from some 150 countries worldwide, and 8,500 staff.

For nearly 200 years, King’s students and staff have used their knowledge and insight to make a positive impact on people, society and the planet. Focused on delivering positive change at home in London, across the UK and around the world, King’s is building on its history of addressing the world’s most urgent challenges head on to accelerate progress, make discoveries and pioneer innovation. Visit the website to find out more about Vision 2029, which sets out bold ambitions for the future of King’s as we look towards our 200th anniversary.

World-changing ideas. Life-changing impact: kcl.ac.uk/news

Journal

Nature Medicine

Method of Research

Randomized controlled/clinical trial

Subject of Research

People

Article Publication Date

24-Jul-2025

Ibogaine appears to treat traumatic brain injuries in veterans

Stanford Medicine

For military veterans, many of the deepest wounds of war are invisible: Traumatic brain injuries resulting from head trauma or blast explosions are a leading cause of post-traumatic stress disorder, anxiety, depression and suicide among veterans. Few treatments have been effective at diminishing the long-term effects of TBI, leaving many veterans feeling hopeless.

Now, Stanford Medicine researchers have discovered that the plant-based psychoactive drug ibogaine, when combined with magnesium to protect the heart, safely and effectively reduces PTSD, anxiety and depression and improves functioning in veterans with TBI.

In a study to be published July 24, 2025, in Nature Mental Health, Williams and his team analyzed electroencephalography and MRI scans collected from a cohort of 30 veterans to uncover the neural mechanisms underlying the cognitive improvements. They found, for example, that veterans who improved in executive function after ibogaine treatment tended to show an increase in a type of brain wave known as theta rhythms. They also found that veterans with lowered PTSD symptoms after treatment tended to show a reduction in the complexity of brain activity in the cortex.

The researchers speculate that stronger theta rhythms may encourage neuroplasticity and cognitive flexibility, while less complex cortical activity may lower the heightened stress response seen in PTSD. Brain activity patterns before treatment could also be used to identify patients who would benefit most from ibogaine therapy.

“No other drug has ever been able to alleviate the functional and neuropsychiatric symptoms of traumatic brain injury,” said Nolan Williams, MD, an associate professor of psychiatry and behavioral sciences. “The results are dramatic, and we intend to study this compound further.”

The new study expands on a study published online Jan. 5, 2024, in Nature Medicine.

Alternatives

Traumatic brain injury is defined as a disruption in the normal functioning of the brain resulting from external forces — such as explosions, vehicle collisions or other bodily impacts. The trauma associated with TBI can lead to changes in the function and/or structure of the brain, which, in turn, contributes to neuropsychiatric symptoms.

Hundreds of thousands of troops serving in Afghanistan and Iraq have sustained TBIs in recent decades, and these injuries are suspected of playing a role in the high rates of depression and suicide seen among military veterans. With mainstream treatment options not fully effective for some veterans, researchers have sought therapeutic alternatives.

Ibogaine is a naturally occurring compound found in the roots of the African shrub iboga, and it has been used for centuries in spiritual and healing ceremonies. More recently, it has gained interest from the medical and scientific communities for its potential to treat opioid and cocaine addiction, and research has suggested that it increases signaling of several important molecules within the brain, some of which have been linked to drug addiction and depression. Since 1970 ibogaine has been designated as a Schedule I drug, preventing its use within the U.S., but clinics in both Canada and Mexico offer legal ibogaine treatments.

“There were a handful of veterans who had gone to this clinic in Mexico and were reporting anecdotally that they had great improvements in all kinds of areas of their lives after taking ibogaine,” Williams said. “Our goal was to characterize those improvements with structured clinical and neurobiological assessments.”

Capturing ‘before and after’

For the study published in January of 2024, Williams and his colleagues at Stanford Medicine teamed up with VETS, Inc., a foundation that helps facilitate psychedelic-assisted therapies for veterans. With support from VETS, 30 special operations veterans with a history of TBI and repeated blast exposures, almost all of whom were experiencing clinically severe psychiatric symptoms and functional disabilities, had independently scheduled themselves for treatment with magnesium and ibogaine at a clinic in Mexico.

Before the treatment, the researchers gauged the participants’ levels of PTSD, anxiety, depression and functioning based on a combination of self-reported questionnaires and clinician-administered assessments. Participants then traveled to a clinic in Mexico run by Ambio Life Sciences, where under medical monitoring they received oral ibogaine along with magnesium to help prevent heart complications that have been associated with ibogaine. The veterans then returned to Stanford Medicine for post-treatment assessments.

“These men were incredibly intelligent, high-performing individuals who experienced life-altering functional disability from TBI during their time in combat,” Williams said. “They were all willing to try most anything that they thought might help them get their lives back.”

At the beginning of the study, participants were experiencing clinically significant levels of disability as measured by the World Health Organization Disability Assessment Scale 2.0, which assesses disability in six functional domains, including cognition, mobility, self-care, getting along, life activities and community participation. In addition, 23 met the criteria for PTSD, 14 for an anxiety disorder and 15 for alcohol use disorder. In their lifetimes, 19 participants had been suicidal and seven had attempted suicide.

Life-changing results

On average, treatment with ibogaine immediately led to significant improvements in functioning, PTSD, depression and anxiety. Moreover, those effects persisted until at least one month after treatment — the endpoint of the study.

Before treatment, the veterans had an average disability rating of 30.2 on the disability assessment scale, equivalent to mild to moderate disability. One month after treatment, that rating improved to 5.1, indicating no disability. Similarly, one month after treatment participants experienced average reductions of 88% in PTSD symptoms, 87% in depression symptoms and 81% in anxiety symptoms relative to how they were before ibogaine treatment. Formal cognitive testing also revealed improvements in participants' concentration, information processing, memory and impulsivity.

“I wasn’t willing to admit I was dealing with any TBI challenges. I just thought I’d had my bell rung a few times — until the day I forgot my wife’s name,” said Craig, a 52-year-old study participant from Colorado who served 27 years in the U.S. Navy. “Since [ibogaine treatment], my cognitive function has been fully restored. This has resulted in advancement at work and vastly improved my ability to talk to my children and wife.”

“Before the treatment, I was living life in a blizzard with zero visibility and a cold, hopeless, listless feeling,” said Sean, a 51-year-old veteran from Arizona with six combat deployments who participated in the study and says ibogaine saved his life. “After ibogaine, the storm lifted.”

Importantly, there were no serious side effects of ibogaine and no instances of the heart problems that have occasionally been linked to ibogaine. During treatment, veterans reported only typical symptoms such as headaches and nausea.

Lessons for PTSD, depression and anxiety

The researchers hope to launch future studies to further understand how the drug might be used to treat TBI. In fact, based in part on the promising results of the team’s ibogaine studies, Texas recently approved a $50 million initiative to fund clinical trials of ibogaine. The initiative — one of the largest government investments in psychedelic therapy — will provide matching state funds to private investments in ibogaine trials that may lead to FDA approval.

Williams believes ibogaine’s drastic effects on TBI suggest that it holds broader therapeutic potential for other neuropsychiatric conditions. “In addition to treating TBI, I think this may emerge as a broader neuro-rehab drug,” Williams said. “I think it targets a unique set of brain mechanisms and can help us better understand how to treat other forms of PTSD, anxiety and depression that aren’t necessarily linked to TBI.”

The study was independently funded by philanthropic gifts from Steve and Genevieve Jurvetson. Stanford Medicine received no funding from VETS, Inc. or Ambio.

Journal

Nature Mental Health

DOI

10.1038/s44220-025-00463-x

Method of Research

Observational study

Subject of Research

People

Article Title

Magnesium–ibogaine therapy effects on cortical oscillations and neural complexity in veterans with traumatic brain injury

Article Publication Date

24-Jul-2025

MENOPAUSE IS NOT A DISEASE

Breaking the silence: MyMenoplan.org empowers women to take charge of menopause

Clinical trial shows the NIH-funded website boosts treatment intentions, menopause knowledge and decision-making confidence among users

University of California - San Diego

Menopause remains one of the most under-discussed stages of life, even though more than 1 million women in the United States experience this natural biological transition each year. Often shrouded in stigma and misinformation, menopause is rarely addressed openly — even though it can profoundly affect a person’s physical, emotional and mental health.

To help bridge this gap, clinicians and researchers who have collaborated on women’s health for over 25 years created MyMenoplan.org. The comprehensive, evidence-based website offers personalized menopause information and decision-making tools designed to empower women to make informed healthcare choices. The website is open and free to everyone and does not require any type of registration or entering of personal information.

“This tool guides a person through a discussion of the symptom, explains why it is common during menopause, and outlines treatment options that may help alleviate it,” said Andrea LaCroix, Ph.D., M.P.H., distinguished professor at the Herbert Wertheim School of Public Health and Human Longevity Science at University of California San Diego and principal investigator of the trial.

In a recent randomized controlled trial published in the journal Maturitas that assessed the impact of MyMenoplan.org, researchers found that women using MyMenoplan.org reported:

Increased intention to obtain treatment
Improved menopause knowledge
Enhanced decision-making progress
Greater likelihood of revisiting and recommending the website

“One of the unique features of the website is the ‘Create My Menoplan’ tab, where a woman can explore a symptom she’s experiencing, such as hot flashes, night sweats or trouble sleeping,” said LaCroix. “The goal is for women to create their own personalized plan to explore treatments, prepare to speak with their doctors, and try different approaches to feel more comfortable during the menopause transition.”

Implications for Women's Health

Findings from this trial support MyMenoplan.org, the first National Institutes of Health-funded website on menopause, as an effective resource for healthcare providers counseling patients who are experiencing perimenopause (the period of transition into menopause) or postmenopause (defined as having gone more than a year without a menstrual period).

From increased risks of osteoporosis and cardiovascular disease to sleep disturbances and mood changes, the health consequences of untreated or poorly managed menopause can be significant. Yet, due to cultural taboos, lack of education and gaps in medical training, many women navigate this phase without the support or information they need.

“Ideally, when a woman schedules an appointment with their doctor to discuss menopause, her doctor might say, ‘I look forward to speaking with you. Please review this website before your visit and bring any questions you have after reading through the information,’” said LaCroix.

“It's time to break the silence and bring menopause into the public conversation — because awareness is the first step toward better health outcomes.”

Co-authors include: Leslie B. Snyder, University of Connecticut; Katherine M. Newton, Kaiser Permanente Washington Health Research Institute; Hui Xin Ng, UC San Diego; Susan D. Reed, University of Washington School of Medicine; Katherine A. Guthrie, Fred Hutchinson Cancer Center; and Viviana Zambrano, University of Connecticut.

This research was funded, in part, by the National Institutes of Health, National Institute on Aging (5R01AG048209).

Disclosures: The authors do not have any conflicts of interest to report.

Journal

Maturitas

DOI

10.1016/j.maturitas.2025.108630

Method of Research

Randomized controlled/clinical trial

Subject of Research

People

Article Title

Positive impact of a menopause website – MyMenoplan.org – on treatment intentions, knowledge, and decision making: A randomized controlled trial

Women of African ancestry may be biologically predisposed to early onset or aggressive breast cancers

University of Notre Dame

image:
Crislyn D'Souza-Schorey, the Morris Pollard Professor of Biological Sciences at Notre Dame.
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Credit: (Photo by Barbara Johnston/University of Notre Dame)

While the incidence of breast cancer is highest for white women, Black women are more likely to have early-onset or more aggressive subtypes of breast cancer, such as triple-negative breast cancer. Among women under 50, the disparity is even greater: young Black women have double the mortality rate of young white women.

Now research from the University of Notre Dame is shedding light on biological factors that may play a role in this disparity. The study published in iScience found that a population of cells in breast tissues, dubbed PZP cells, send cues that prompt behavioral changes that could promote breast cancer growth.

Funded by the National Cancer Institute at the National Institutes of Health, the study set out to explore what biological differences in breast tissue could be related to early onset or aggressive breast cancers. Most breast cancers are carcinomas, or a type of cancer that develops from epithelial cells. In healthy tissue, epithelial cells form linings in the body and typically have strong adhesive properties and do not move.

The researchers focused on PZP cells as previous studies had shown that these cells are naturally and significantly higher in healthy breast tissues of women of African ancestry than in healthy breast tissues of women of European ancestry. While PZP cell levels are known to be elevated in breast cancer patients in general, their higher numbers in healthy, African ancestry tissues could hold clues to why early-onset or aggressive breast cancers are more likely to occur in Black women.

“The disparity in breast cancer mortality rates, particularly among women of African descent, is multifaceted. While socioeconomic factors and delayed diagnosis may be contributing factors, substantial emerging evidence suggests that biological and genetic differences between racial groups can also play a role,” said Crislyn D'Souza-Schorey, the Morris Pollard Professor of Biological Sciences at Notre Dame and corresponding author of the study.

The study showed how PZP cells produce factors that activate epithelial cells to become invasive, where they detach from their primary site and invade the surrounding tissue.

For example, a particular biological signaling protein known as AKT is often overactive in breast cancers. This study showed that PZP cells can activate the AKT protein in breast epithelial cells, which in part allows them to invade the surrounding environment. PZP cells also secrete and deposit certain proteins outside the cell that guide the movement of breast epithelial cells as they invade.

Overall, the results of the study emphasize multiple mechanisms by which PZP cells may influence the early stages of breast cancer progression and their potential contribution to disease burden.

The researchers also looked at how a targeted breast cancer drug, capivasertib, which inhibits the AKT protein, impacted PZP cells and found it markedly reduced the effects of the PZP cells on breast epithelial cells.

“It’s important to understand the biological and genetic differences within normal tissue as well as tumors among racial groups, as these variations could potentially influence treatment options and survival rates. And consequently, in planning biomarker studies, cancer screenings or clinical trials, inclusivity is important,” said D'Souza-Schorey, also an affiliate of Notre Dame’s Berthiaume Institute for Precision Health and Harper Cancer Research Institute.

D'Souza-Schorey and her lab collaborated with the Indiana University Melvin and Bren Simon Comprehensive Cancer Center’s Susan G. Komen Tissue Bank to access PZP cells and epithelial cells isolated from healthy breast tissues of both African and European ancestry. The cell lines were then grown in a three-dimensional environment, mimicking the way the cells would behave in living tissues and organs.

The research team also worked with the Notre Dame Integrated Imaging Facility for the study.

In addition to D’Souza-Schorey, co-authors include Madison Schmidtmann, Victoria Elliott, James W. Clancy, and Zachary Schafer from Notre Dame and Harikrishna Nakshatri from and IU Simon Comprehensive Cancer Center.

Micrograph of PZP cells (green) and breast epithelial cells (red) grown in 3D.

Credit

(Madison Schmidtmann and James Clancy, D’Souza-Schorey lab.)

Journal

iScience

DOI

10.1016/j.isci.2025.112686

Subject of Research

Cells

Article Title

Ancestry-linked stromal variations impact breast epithelial cell invasion

LA REVUE GAUCHE - Left Comment: Search results for POINTER SISTERS

Advances in chemistry unlock new pathways for industrial carbon capture, new research finds

Heriot-Watt University

image:
Professor Mercedes Maroto-Valer, Heriot-Watt UniversityHeriot-Watt University.
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Credit: Heriot-Watt University

Recent key advances in chemistry could tackle emissions from the world’s most polluting industries, according to a new study from a team led by Professor Mercedes Maroto‑Valer, Champion and Director of the Industrial Decarbonisation Research and Innovation Centre (IDRIC) and Director of the Research Centre for Carbon Solutions (RCCS) at Heriot-Watt University, and Dr Steve Griffiths, Professor and Vice Chancellor for Research at American University of Sharjah (AUS).

Published in Nature Reviews Chemistry, one of the world’s most prestigious scientific journals, the paper, titled “Chemistry advances driving industrial carbon capture technologies,” discusses how breakthroughs in chemistry are enabling more efficient and scalable carbon capture solutions for heavy industries such as oil and gas, steel, cement, aluminium and chemicals. Together, these industries account for 40 percent of global greenhouse gas emissions and 85 percent of manufacturing-related emissions.

Carbon capture technology involves capturing CO₂ directly from industrial and energy sources before it enters the atmosphere, then transporting and storing or repurposing it to avoid climate impact. According to the Intergovernmental Panel on Climate Change (IPCC), global carbon capture capacity must increase more than 100-fold—from around 50 million tonnes today to between 4 and 6 billion tonnes annually by 2050—to help limit global warming to 1.5 °C.

While carbon capture technologies are already established in the oil and gas industry, their adoption across other carbon-intensive industries like cement, steel, and chemicals has lagged significantly. This review shows that advances in chemistry are increasingly positioning carbon capture as a viable solution for large-scale industrial decarbonization.

The research highlights innovations including novel amine blends that reduce energy consumption by over 30 percent, metal-organic frameworks (MOFs) that can selectively capture CO2 with extremely high efficiency, and new electroswing technologies that operate at low temperature using renewable electricity instead of energy-intensive heating.

“With heavy industries accounting for a major share of global emissions, advancing these technologies is critical if we’re serious about ever achieving net-zero emissions. Our review highlights the state-of-the-art chemistry behind industrial-scale carbon capture and potential breakthroughs that may further make industrial carbon capture more efficient, scalable and cost-effective. Our aim is for this work to provide the insights necessary for carbon capture to advance at the pace required to achieve global sustainability targets,” said Dr.Griffiths.

The paper reviews five main types of industrial carbon capture technologies—absorption, adsorption, membrane separation, cryogenic gas separation and electroswing systems—and provides insights into how chemistry innovations are improving both their effectiveness and affordability.

“Our work has identified carbon dioxide capture technologies that have progressed to the early stages of development to decarbonise industrial sectors, with a focus on the chemistry that underpins these technologies," said Professor Mercedes Maroto‑Valer.

"We took a global perspective, recognising that carbon capture must be tailored to local contexts. The performance parameters outlined in our research enable industry players to compare materials and technologies more effectively than has previously been possible. We believe this novel approach can help players across both industry and academia pinpoint research opportunities to lower the cost and scale up the commercial deployment of the carbon capture technologies available today."

Additional authors include Prof John M. Andresen from the School of Engineering and Physical Sciences and Dr Jeannie Z. Y. Tan from the Research Centre for Carbon Solutions (RCCS), both at Heriot‑Watt University, as well as Mr Joao M. Uratani from the University of Sussex’s Science Policy Research Unit (SPRU).

This is the second high-profile study in the past year involving researchers from AUS and Heriot-Watt University, following a recent collaboration that proposed green flight paths and the adoption of sustainable aviation fuel as strategies for decarbonising long-haul air traffic.

The published paper is available at www.nature.com/articles/s41570-025-00733-3.

For more information about AUS’ research, visit: www.aus.edu/research.

Journal

Nature Reviews Chemistry

Article Title

Chemistry advances driving industrial carbon capture technologies

Deep learning-based structural characterization and mass transport analysis of CO2 reduction catalyst layers

Higher Education Press

As global efforts to combat climate change intensify, electrochemical CO₂ reduction reaction (CO2RR) stands out as a critical technology for converting greenhouse gases into valuable fuels and chemicals. Yet, a persistent bottleneck has hindered progress: the lack of precise tools to characterize and optimize the porous catalyst layers where reactions occur. A new study published in Frontiers in Energy resolves this challenge by deploying deep learning (DL) to map microscopic structures and simulate mass transport in CO₂RR catalyst layers with unprecedented accuracy.

A research team at Shanghai Jiao Tong University has developed a systematic framework that combines semantic-segmentation AI models with experimental validation to analyze catalyst layers (CLs). Using silver nanoparticles as catalysts and Nafion ionomer as a binder, the team fabricated CLs with varying ionomer-to-catalyst (I/C) ratios (0.2, 0.4, and 0.6) to dissect how composition affects performance.

Key Findings

AI Outperforms Traditional Methods: Among five DL models tested, DeepLabV3plus achieved the highest segmentation accuracy (91.29%), surpassing conventional thresholding techniques (72.35–77.42%). This enabled precise extraction of pore parameters like porosity and pore size distribution, validated against mercury intrusion porosimetry (MIP).
Optimal I/C Ratio Identified: CLs with an I/C ratio of 0.2 exhibited a twofold increase in gas diffusion distance (672.88 nm vs. 321.38 nm for I/C = 0.6), enabling 89% Faradaic efficiency (FE) for CO production at 250 mA/cm²—the highest reported in the study.
Structure-Performance Link: Excessive ionomer (I/C ≥ 0.4) clogged macropores, reducing CO₂ accessibility and FE by 12%. Simulations confirmed that lower ionomer content preserved open pore networks critical for long-range mass transport.

The integrated framework translates nanoscale morphology directly into device-level performance metrics, providing a scalable blueprint for industrial CO₂ electrolyzers. By minimizing ionomer loading to 0.2, catalyst layers can sustain high current densities without sacrificing selectivity or durability, moving carbon-neutral fuel production closer to market deployment.

Journal

Frontiers in Energy

DOI

10.1007/s11708-025-1029-x

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Deep learning-based structural characterization and mass transport analysis of CO2 reduction catalyst layers

Article Publication Date

25-Jul-2025