Rebecca Follett, Rachel Davey
April Binder (Biological Sciences)
Cold exposure has been shown to affect metabolic activity and adipose tissue. Therefore we aimed to examine the differences caused by prolonged cold exposure in two strains of mice. We used a transgenic mouse expressing the human non-steroidal activated gene 1 (NAG). NAG mice are lean and have a higher ratio of brown to white fat compared to the wildtype (WT) mice. The prepubertal mice were held at a constant temperature of 10℃ for one week. After cold exposure the animals were euthanized and both white and brown fat were collected, sectioned, stained, and analyzed. White fat stores lipids as an energy source, therefore the size of the cells was analyzed and compared between the two strains of mice. The main function of brown fat is to maintain a constant body temperature via thermogenesis. These cells are very small therefore we performed qualitative analysis of this tissue. After cold exposure, white fat has been shown to resemble a third type of fat, beige fat. Beige fat can provide a thermogenic effect or characteristic, but it is unable to significantly support brown fat in maintaining a constant body temperature. It is expected that the NAG mice will show more beige fat than the WT after prolonged cold exposure.
Keywords: Adipose Tissue, Mice, Thermogenesis