Effects of Squirrel Gut Microbiota Transfer on Fat Accumulation in Outbred Mice

Abstract

Obesity has been defined as buildup of adipose tissue, but adipose tissue itself is not the cause of the effects associated with obesity. By examining the microbiota of the digestive tract in hibernating animals, it was found TNF-a and IL-6 were present in higher concentrations in obese animals. Gut microbes from the ileum and proximal colon of post-hibernation thirteen-lined ground squirrels (13LGS) were extracted and placed via gavage into DO and CD-1 mice. Mice were euthanized, and ileum, colon, and white adipose tissue (WAT) was collected. Sandwich ELISAs were used to analyze levels of cytokines present in the tissue. Microbiota from 13LGS awake for 48 hours after hibernation allowed for the highest amount of adiposity gain per mouse per week. DO mice were more responsive to microbiota transfer.