Molecular Evidence of Heat Stress Damage to Gut, Liver, and Brain in Elderly Mice

Researchers from the University of California, Irvine have discovered molecular evidence of the damaging impact heat stress has on the gut, liver, and brain in elderly mice. The study, published in the journal Scientific Reports, is one of the first to investigate the effects of heat stress on the gut-liver-brain communication or “axis” at a molecular level, potentially leading to the development of precise prognostic and therapeutic interventions.

The Importance of the Gut-Liver-Brain Axis

The gut, liver, and brain have a complex and multidirectional communication system that influences various aspects of human health, from the gastrointestinal tract to the nervous system. Understanding this crucial biological conversation is essential to protecting human health, particularly in the aging population.

“Inflammation in the brain and spine contributes to cognitive decline, compromises the ability to form new neurons and exacerbates age-related diseases,” said corresponding author Saurabh Chatterjee, a professor of environmental & occupational health at the UC Irvine Program in Public Health. “By investigating the effects of heat stress on the gut-liver-brain crosstalk, we can better protect our increasingly vulnerable aging population.”

Liver-Produced Protein ORM2 as a Potential Biomarker

Using RNA analysis and bioinformatics, the researchers found evidence of heat stress-affected genes in the brain and liver of elderly, heat-stressed mice. They observed a significant increase in the production of ORM2, a liver-produced protein, in the heat-stressed mice compared to the unstressed control group.

The increased secretion of ORM2 is believed to be a coping mechanism due to gut inflammation and imbalance, and it may impact the brain through a leaky blood-brain barrier. The study also shows the potential to use ORM2 for targeted biomarker interventions to prevent liver disease in heat exposure.

“Our findings have the potential to be used for the development of prognostic and therapeutic markers for precise interventions,” said Chatterjee. “In a dynamically changing global landscape, the imminent threat of climate change is evident in rising temperatures, raising concerns about intermittent heat waves. Our heating planet is undoubtedly leading to acute and chronic heat stress that harms the health of our aging population.”