Medical Bulletin 9/June/2025

Here are the top medical bulletins for the day:

Trial Shows Low Cost Antibiotic Use May Reduce Preterm Births in Women with HIV

A new study published in the New England Journal of Medicine has found that a commonly used, low-cost antibiotic may significantly reduce the risk of preterm births, particularly among pregnant women living with HIV. The findings come from the Cotrimoxazole for Mothers to Improve Birthweight in Infants (COMBI) trial, a randomized controlled study.

Globally, one in four live-born infants is either preterm, small for gestational age, or has a low birth weight—conditions that contribute heavily to under-5 child mortality. Prematurity is now the leading cause of death among children under five. Maternal infections and inflammation, especially in women with HIV, have been closely linked to adverse birth outcomes. The COMBI trial was designed to investigate whether administering a daily dose of trimethoprim–sulfamethoxazole—a broad-spectrum antimicrobial with anti-inflammatory properties—could reduce these risks.

A total of 993 pregnant women from three antenatal clinics in Shurugwi, Zimbabwe, participated in the study. They were randomly assigned to receive either 960 mg of the antibiotic or a placebo daily. All participants received routine antenatal care, and detailed data on their birth outcomes were collected and analyzed.

While the study found no significant difference in birthweights between the two groups, it revealed a notable reduction in preterm births. Only 6.9% of women in the antibiotic group delivered prematurely, compared to 11.5% in the placebo group. Strikingly, among the 131 women with HIV, just 2% of births in the antibiotic group were preterm, compared with 14% in the placebo group. Babies in the treatment group also had an average increase of 177 grams in birthweight.

Bernard Chasekwa, first author, said: “Our trial, conducted within routine antenatal care and enrolling women predominantly from rural areas, showed that trimethoprim-sulfamethoxazole did not improve birthweight, which was our main outcome. However, there was an intriguing suggestion that it may have improved the length of pregnancy and reduced the proportion of preterm births. We now need to repeat this trial in different settings around the world to see whether antibiotics during pregnancy can help reduce the risk of prematurity.”

Reference: https://www.qmul.ac.uk/media/news/2025/medicine-and-dentistry/fmd/antibiotics-taken-during-pregnancy-may-reduce-preterm-births.html

How Longer Reproductive Years in Women Lead to Healthier Brain Aging: Study

A new study suggests that the number of years a woman spends in her reproductive phase i.e. between her first period and menopause, may be linked to how well her brain ages later in life. Findings are published in Gigascience journal.

Researchers analysed brain scans from over 1,000 postmenopausal women and found that women who had their first period earlier, experienced menopause later, or had a longer reproductive span showed signs of slower brain aging.

“These findings support the idea that estradiol – the most potent and prevalent form of estrogen during a woman’s reproductive years – may help protect the brain as it ages,” says lead researcher Associate Professor Eileen Lueders, of the University of Auckland’s School of Psychology.

The research may point toward the potential for health interventions such as hormone treatment in the years leading up to menopause and immediately afterward to combat an increased risk of Alzheimer’s for some women.

Estradiol levels rise at puberty, remain high during most of a woman’s reproductive life, and then decline sharply around menopause. This drop in estradiol has been linked to an increased risk of dementia and other age-related brain conditions. Animal studies have shown that estradiol can help the brain by supporting neuroplasticity, protecting against inflammation, and improving communication between brain cells.

While this new study adds to the growing evidence that estradiol may play a protective role in brain health, Luders cautions that the effects were small, and estradiol levels were not directly measured. Other factors—like genetics, lifestyle, and overall health— also influence brain aging.

Reference: Eileen Luders, Inger Sundström Poromaa, Claudia Barth, Christian Gaser, A Case for estradiol: younger brains in women with earlier menarche and later menopause, GigaScience, Volume 14, 2025, giaf060, https://doi.org/10.1093/gigascience/giaf060

New Gene Therapy for Alzheimer’s May Preserve Cognitive Function

A study published in Signal Transduction and Targeted Therapy by researchers at the University of California San Diego School of Medicine introduces a gene therapy that may offer a powerful new approach to treating Alzheimer’s disease. Unlike current therapies that primarily target protein deposits in the brain, this innovative strategy focuses on altering the behavior of brain cells themselves to prevent damage and preserve cognitive function.

Current treatments for Alzheimer’s manage symptoms but do not stop the underlying disease process. The new gene therapy, developed by UC San Diego researchers, aims to halt or even reverse the progression of the disease by addressing its root causes.

In experiments using mice, the team delivered the gene therapy at the symptomatic stage of Alzheimer’s and found that it preserved hippocampal-dependent memory—a vital aspect of cognition that is typically impaired in patients. Notably, the treated mice exhibited gene expression patterns that closely resembled those of healthy mice, suggesting that the therapy may restore diseased cells to a more normal, functional state.

The researchers found that delivering the treatment at the symptomatic stage of the disease preserved hippocampal-dependent memory, a critical aspect of cognitive function that is often impaired in Alzheimer's patients. Compared to healthy mice of the same age, the treated mice also had a similar pattern of gene expression, suggesting that the treatment has the potential to alter the behavior of diseased cells to restore them to a healthier state.

Although additional studies are needed before the therapy can be tested in human trials, the findings represent a promising step toward a more effective and long-term solution for Alzheimer’s disease.

Reference: https://www.universityofcalifornia.edu/news/alzheimers-gene-therapy-shows-promise-preserving-cognitive-function#:~:text=This%20scan%20of%20a%20mouse,behavior%20of%20diseased%20brain%20cells.