Medical Bulletin 19/November/2025 - Video

Here are the top medical news for the day:

New research links cat exposure to doubled risk of developing schizophrenia

A surprising new meta-analysis is stirring fresh debate about the link between cat ownership and schizophrenia-related disorders. Researchers from the Queensland Centre for Mental Health Research in Australia reviewed 17 studies spanning 11 countries over four decades, revealing that people exposed to cats had about twice the odds of developing psychotic illnesses compared to those without cat exposure.

These findings, published in Schizophrenia Bulletin, highlight a statistically significant association but do not prove that cats cause schizophrenia.

Schizophrenia is a chronic mental disorder affecting about 23 million people worldwide, or roughly 1 in 345 individuals. Its onset typically occurs in late adolescence or early adulthood, with men often affected earlier than women. Schizophrenia causes disruptions in thinking, perception, and emotional responsiveness, making it one of the leading causes of disability globally. Despite its impact, many people with schizophrenia do not receive adequate mental health care, highlighting a persistent treatment gap worldwide.

The main hypothesis centers on Toxoplasma gondii, a parasite commonly hosted by cats that can enter the human body via contact with cat feces, bites, or contaminated food and water. T. gondii can affect the brain’s neurotransmitters, potentially triggering psychotic symptoms. However, researchers caution that association does not mean causation, and many analyzed studies had methodological limitations, including reliance on case-control designs that do not establish cause and effect.

Adding complexity, some studies found no clear link between general cat ownership and psychosis, while others suggest a critical exposure window in childhood may matter most. For example, cat ownership between ages 9–12 was more strongly linked to schizophrenia risk than exposure at broader ages. Conflicting results and low-quality evidence mean that further high-quality, large-scale research is needed to clarify whether cat exposure is a true risk factor.

For now, cat owners should not panic but exercise sensible hygiene, such as regular litter cleaning and handwashing after handling cats or their waste. This evolving research broadens our understanding of environmental contributors to mental illness, emphasizing that psychiatric conditions arise from a complex interplay of genetics, infections, and lifestyle factors.

REFERENCE: John J McGrath, Carmen C W Lim, Sukanta Saha, Cat Ownership and Schizophrenia-Related Disorders and Psychotic-Like Experiences: A Systematic Review and Meta-Analysis, Schizophrenia Bulletin, Volume 50, Issue 3, May 2024, Pages 489–495, https://doi.org/10.1093/schbul/sbad168

New analysis uncovers surprising health benefits of mushrooms beyond low calories

Mushrooms are gaining recognition not only for their unique taste but also for exceptional health benefits and nutritional value. A recent review in Critical Reviews in Food Science and Nutrition analyzed 22 human studies exploring how whole mushroom consumption affects risk markers for cardiometabolic diseases like diabetes, stroke, and heart conditions.

Mushrooms are low-calorie, nutrient-dense fungi rich in dietary fiber, potassium, B vitamins, selenium, and unique antioxidants like ergothioneine and L-ergothioneine. When exposed to ultraviolet light, they also provide vitamin D2, essential for immune and bone health.

The review synthesized 22 human studies, including 16 experimental trials and 6 observational studies, assessing how whole mushroom consumption influences cardiometabolic biomarkers such as blood lipids, glucose, blood pressure, inflammation, and immune function. Participants consumed varying doses of mushrooms (13 to 300 grams daily), either as part of their regular diets or within healthier eating patterns. Studies spanned diverse populations and were evaluated for methodological quality, though many were limited by short durations and small sample sizes.

Findings showed that regular mushroom intake lowered serum triglycerides, fasting blood glucose, and slightly reduced blood pressure without affecting LDL, HDL, or inflammation markers. It also enhanced immune defense through higher salivary IgA. These benefits come from compounds like beta-glucan, chitin, potassium, and ergothioneine that improve metabolism and reduce oxidative stress.

Mushrooms also contribute to brain health, possibly delaying neurodegenerative diseases like Alzheimer’s and Parkinson’s due to their neuroprotective compounds. Their natural glutamate adds umami flavor, allowing culinary reductions in salt and saturated fats, which benefits heart health.

While most studies are preliminary and involve small populations, mushrooms’ diverse bioactive profiles and low toxicity profile make them a valuable addition to balanced diets for improving metabolic, immune, and cognitive outcomes. Ongoing and future clinical trials will clarify species-specific benefits, optimal intake, and long-term effects.

Integrating 75–100 grams of mushrooms regularly into daily meals is a practical step for families and institutions aiming to boost nutrition with minimal effort.

REFERENCE: Comboni, L. M., Uffelman, C. N., Campbell, C. B., Olson, M. R., & Campbell, W. W. (2025). Mushroom consumption impacts on biomarkers of cardiometabolic disease risk and immune function: a narrative review from a whole food perspective. Critical Reviews in Food Science and Nutrition. 1–15. DOI: 10.1080/10408398.2025.2582603, https://www.tandfonline.com/doi/full/10.1080/10408398.2025.2582603

World’s oldest blood pressure drug maybe effective against aggressive brain tumour: Study

A decades-old drug, hydralazine, traditionally used to treat high blood pressure and preeclampsia during pregnancy, is now showing promise in fighting aggressive brain tumors. Scientists at the University of Pennsylvania discovered its molecular mechanism, revealing that hydralazine targets an enzyme called 2-aminoethanethiol dioxygenase (ADO), which acts as an oxygen sensor controlling blood vessel constriction.

The findings of the research are published in Science Advances.

Hydralazine lowers blood pressure by directly relaxing the smooth muscles in the walls of small arteries (arterioles). It interferes with calcium metabolism in vascular smooth muscle, reducing intracellular calcium levels. This relaxation causes the blood vessels to dilate, decreasing peripheral resistance and allowing blood to flow more easily. This vasodilation reduces blood pressure and decreases the workload on the heart. Because hydralazine stimulates the sympathetic nervous system, it is often prescribed with a beta-blocker to prevent rapid heart rate as a side effect.

By binding to and inhibiting ADO, hydralazine “silences” this oxygen alarm, preventing blood vessels from tightening and lowering blood pressure. Remarkably, this action also disrupts a survival mechanism in glioblastoma cells, the most aggressive brain tumors, causing them to enter a dormant state and halting their growth without triggering harmful inflammation or resistance.

Using advanced techniques like X-ray crystallography and tumor cell testing, the researchers detailed how hydralazine’s interaction with ADO provides a direct link between hypertensive disorders and brain cancer biology. This discovery not only enhances understanding of hydralazine’s longstanding use in maternal health but also opens a new therapeutic avenue for designing safer, targeted brain cancer treatments.

While hydralazine is an established drug for managing pregnancy-related hypertension, these findings could lead to repurposing it as part of brain cancer therapy, potentially improving outcomes for patients with few options. Researchers emphasize the importance of further studies to develop optimized versions of hydralazine that maximize anticancer effects while maintaining safety.

This breakthrough exemplifies how revisiting well-known medications can uncover unexpected benefits, highlighting the potential of drug repurposing to accelerate new treatments for challenging diseases.

REFERENCE: Kyosuke Shishikura et al. ,Hydralazine inhibits cysteamine dioxygenase to treat preeclampsia and senesce glioblastoma.Sci. Adv.11,eadx7687(2025).DOI:10.1126/sciadv.adx7687