TOP MEDICAL NEWS O2/AUGUST/2022

Chemicals produced in the digestive tract by gut microbes after eating red meat may help explain part of the higher risk of cardiovascular disease associated with red meat consumption, according to new research published today in the American Heart Association's peer-reviewed journal Arteriosclerosis, Thrombosis, and Vascular Biology (ATVB).

Previous research has found that certain metabolites are associated with a greater risk of cardiovascular disease. One of these metabolites is TMAO, or trimethylamine N-oxide, which is produced by gut bacteria to digest red meat that contains high amounts of the chemical L-carnitine.

Ref:

Meng Wang et. al, Arteriosclerosis Thrombosis, and Vascular Biology, 1-Aug-2022, 10.1161/ATVBAHA.121.316533

2. Prevention of recurrent kidney stones by a high calcium potassium diet

Changes in diet are often prescribed to prevent recurrent symptomatic kidney stones. However, little research is available regarding dietary changes for those who have one incident of kidney stone formation versus those who have recurrent incidents.

Mayo Clinic researchers designed a prospective study to investigate the impact of dietary changes.

Dietary factors were based on a questionnaire administered to 411 patients who had experienced first-time symptomatic kidney stones and a control group of 384 people — all of whom were seen at Mayo Clinic in Rochester and Mayo Clinic in Florida between 2009 and 2018. The findings, which were published in Mayo Clinic Proceedings, show that lower dietary calcium and potassium, as well as lower intake of fluids, caffeine, and phytate, are associated with higher odds of experiencing a first-time symptomatic kidney stone.

Ref:

Andrew Rule et. al, Dietary Risk Factors for Incident and Recurrent Symptomatic Kidney Stones, Mayo Clinic Proceedings, 1-Aug-2022,

3. Disordered eating in children

A new study of nearly 12,000 9- and 10-year-olds, published this week in JAMA Pediatrics, provides key insights that help fill that gap. Researchers examined how age, sex, weight, and puberty stage were related to behaviors such as binge eating and vomiting to control weight.

"The first major takeaway is that these behaviors are more common than we've seen before, with a prevalence of up to 5% in some cases," said the study's lead author, Stuart Murray.

Contrary to cultural assumptions, the researchers found that boys and girls were equally likely to engage in disordered eating. The analysis also revealed that children with higher body mass indexes (BMIs), as well as those further along in puberty, faced an elevated risk.

Ref:

Stuart Murray et. al, Prevalence of disordered eating and associations with sex, pubertal maturation, and weight in children in the US, JAMA Pediatrics, 1-Aug-2022, 10.1001/jamapediatrics.2022.2490

4. Fast-acting immune cells which provide powerful protection against stroke

A unique subset of white blood cells confers fast-acting and lasting protection against ischemic stroke in mice, University of Pittsburgh neurologists and immunologists reported in the Journal of Clinical Investigation today.

This study identified a novel subset of CD8+ regulatory-like T cells, or CD8+TRLs, as "first responders" to stroke. Attracted to the site of ischemic injury by a unique "homing" signal released by dying brain cells, CD8+TRLs reach the brain within 24 hours after stroke onset, where they release molecules that provide direct neuroprotective effects, as well as limit inflammation and secondary brain damage.

Because the previous two treatments must be administered very early after the stroke, many people, especially those living in remote areas, are ineligible for those therapies. The remaining 600,000 people are left with symptoms-based treatments and are at high risk of developing long-term health complications, including mobility challenges and, in some cases, speech and cognitive pathologies. In addition, blood clot-busting therapy, in particular, has drawbacks that further limit the number of people benefiting from such therapy.

Ref:

Xiaoming Hu et. al, Neuroprotection against ischemic stroke requires a specific class of early responder T cells in mice, Journal of Clinical Investigation, 1-Aug-2022, DOI: 10.1172/JCI157678