Description
Microbial functions in the host physiology are a result of co-evolution between microbial communities and their hosts. Here we show that cold exposure leads to marked shift of the microbiota composition, referred to as cold microbiota. Transplantation of the cold microbiota to germ-free mice is sufficient to increase the insulin sensitivity of the host, and enable complete tolerance to cold partly by promoting the white fat browning, leading to increased energy expenditure and fat loss. During prolonged cold however, the body weight loss is attenuated, caused by adaptive mechanisms maximising caloric uptake and increasing intestinal, villi and microvilli lengths. This increased absorptive surface is promoted by the cold microbiota - effect that can be diminished by co-transplanting the most downregulated bacterial strain from the Verrucomicrobia phylum, Akkermansia muciniphila, during the cold microbiota transfer. Our results demonstrate the microbiota as a key factor orchestrating the overall energy homeostasis during increased demand. Overall design: Mice were kept 30 days at room temperature or at 6C, 2 per cage, under SPF conditions, with or without administration of antibiotic coctail in drinking water (whole microbiota depletion). Fasted 5h before sacrifice. Segments of proximal jejunum were isoated, flushed gently with PBS and frozen. Each of 12 samples is a pool of two biological replicates (2 biological replicates of the same condition combined into one sample)