Huddling relieves myocardial glycogen synthesis of Brandt’s voles in mild cold environment

Abstract

Background:Small mammals have limited glucose use and limited glycogen accumulation during hypothermia. Huddling is a highly evolved cooperative behavioral strategy in social mammals, allowing adaptation to environmental cooling. As yet, however, is not clear whether this behavior affects the utilization of glycogen in cold environments. Here, we studied the effect of huddling on myocardial glycogen content in Brandt’s voles (Lasiopodomys brandtii) under a mild cold environment (15 °C). Results: Results showed that (1) Compared to the control (22 °C) group (CON), the number of glycogenosomes more than tripled in the cool separated group (CS) in both males and females; whereas the number of glycogenosomes increased in females but was maintained in males in the cool huddling group (CH). (2) The ratio of glycogen synthetase phosphorylation showed a similar trend as the change in glycogenosome number in the three treatment groups in both males and females. (3) Protein expression of glycogen phosphorylase remained stable in males in the three treatment groups but increased in CS group females compared with the CON group. Conclusion:These results indicate that huddling in voles alleviated the increase in myocardial glycogen content caused by the increase of glycogen synthesis under cool environments.