Gut microbiota orchestrates energy homeostasis during cold

Chevalier et al., 2015, Cell 163: 1360–1374

Speaker: Yang Fei(費暘)                                           Time: 13:10~14:00, Mar. 2, 2016

Commentator: Pei-Jan Tsai, PhD (蔡佩珍 老師) Place: Room 601

Abstract:

Mammalian white adipose tissue (WAT) that stores energy under the normal condition is an important regulator of energy homeostasis. During cold, the emergence of brown fat cells in subcutaneous WAT, referred to as WAT browning, and increase of insulin sensitivity and resting energy expenditure are induced to result in cold tolerance (1). It has been shown previously that the intestinal microbiota can influence the body metabolism by affecting energy balance, the authors therefore assumed that the gut microbiota may influence energy homeostasis during cold (2). They first demonstrated that cold exposure markedly changed the composition of the gut microbiota, referred to as cold microbiota. To investigate the importance of microbiota change during cold, they transplanted the cold microbiota to germ-free mice and found that this resulted in increased insulin sensitivity and elevated WAT glucose uptake that lead to increased energy expenditure and cold tolerance. Moreover, the cold microbiota transplanted mice showed a marked increase in the length and absorptive surface of intestine. To uncover the microbiota responsible for the observed gut phenotype, they deeply sequenced the transcriptome of the microbiota collected from proximal jejunum of the cold exposed mice. They showed that the cold microbiota transplantation upregulated the anti-apoptotic genes to reduce intestinal cell apoptosis and increase the intestinal tissue remodeling. Nevertheless, all of these effects were reverted by co-transplanting with the most cold-down-regulated species, Akkermansia muciniphila. In conclusion, the authors demonstrated that by causing WAT browning, reduced apoptosis as well as increased energy expenditure and insulin sensitivity, the cold microbiota is sufficient to induce tolerance to cold.

References:

1.       Guerra, C., Navarro, P., Valverde, A.M., Arribas, M., Bru¨ ning, J., Kozak, L.P., Kahn, C.R., and Benito, M. (2001). Brown adipose tissue-specific insulin receptor knockout shows diabetic phenotype without insulin resistance. J. Clin. Invest. 108: 1205–1213.

2.       Murphy, K.G., and Bloom, S.R. (2006). Gut hormones and the regulation of energy homeostasis. Nature 444: 854–859.