A recent study uncovered the importance of the microbiome in controlling body temperature
Normal body temperature can vary from individual to individual. Despite this variation, however, the average basal body temperature of humans has mysteriously dropped since the 1860s. A recent study points to the gut microbiome as a possible contributing factor in regulating body temperature, both in healthy individuals and during infections. life-threatening.
He to studyConducted by a team of researchers led by Dr. Robert Dickson of the University of Michigan School of Medicine used medical records of patients admitted to the hospital with sepsis and performed experiments in mice to investigate the relationship between the composition of gut bacteria, changes in temperature and health outcomes.
Sepsis, the body’s response to a life-threatening infection, can cause drastic changes in body temperature, the trajectory of which is linked to mortality. Previous work has shown that patients hospitalized with sepsis vary greatly in their responses to temperature, and this variation predicts their survival. However, the causes of this temperature variation, both in sepsis and in health, remain unknown.
To try to understand the cause of this variation, the team analyzed rectal swabs from 116 patients admitted to the hospital. The intestinal microbiota of the patients varied greatly, confirming that it is a potential source of variation. The authors found that this variation in gut bacteria was correlated with the patients’ temperature trajectories during their hospital stay. Specifically, the common bacteria of the phylum Firmicutes were most related to a greater response to fever. These bacteria are common, vary from patient to patient, and are known to produce important metabolites that enter the bloodstream and influence the body’s immune response and metabolism.
To confirm these findings under controlled conditions, the team used mouse models, comparing normal mice with genetically identical mice lacking a microbiome. Experimental sepsis caused drastic changes in the temperature of conventional mice, but had a muted effect on the thermal response of microbiome-naive mice. Among mice with microbiomes, variation in temperature response was strongly correlated with the same bacterial family (Lachnospiraceae) found in humans.
Even healthy, microbiome-negative mice had lower basal body temperatures than conventional mice. Treating normal mice with antibiotics also lowered their body temperature.
The study highlights an underappreciated role of the gut microbiome in body temperature and may explain the decline in basal body temperature over the past 150 years. More research is needed to find out whether targeting the microbiome to modulate body temperature can help modify the prognosis of patients with sepsis.
REFERENCE
Gut microbiome modulates body temperature in both sepsis and health
