The microbiota-gut-brain interaction in regulating host metabolic adaptation to cold in male Brandt's voles (Lasiopodomys brandtii)

Gut microbiota play a critical role in orchestrating metabolic homeostasis of the host. However, the crosstalk between host and microbial symbionts in small mammals are rarely illustrated. We used male Brandt's voles (Lasiopodomys brandtii) to test the hypothesis that gut microbiota and host neurotransmitters, such as norepinephrine (NE), interact to regulate energetics and thermogenesis during cold acclimation. We found that increases in food intake and thermogenesis were associated with increased monoamine neurotransmitters, ghrelin, short-chain fatty acids, and altered cecal microbiota during cold acclimation. Further, our pair-fed study showed that cold temperature can alter the cecal microbiota independently of overfeeding. Using cecal microbiota transplant along with beta 3-adrenoceptor antagonism and PKA inhibition, we confirmed that transplant of cold-acclimated microbiota increased thermogenesis through activation of cAMP-PKA-pCREB signaling. In addition, NE manipulation induced a long-term alteration in gut microbiota structure. These data demonstrate that gut microbiota-NE crosstalk via cAMP signaling regulates energetics and thermogenesis during cold acclimation in male Brandt's voles.