Cold exposure leads to improved mitochondrial activity and glucose tolerance and decreases fatty build up in the liver

This study investigates the role of the lipid droplet coat protein Perilipin 5 (PLIN5) in brown adipose tissue (BAT), which is responsible for heat generation in mammals and is associated with metabolic improvements like increased insulin sensitivity and glucose tolerance. Researchers observed that PLIN5 levels in BAT significantly increased during exposure to cold temperatures.


To understand PLIN5's function, they created mouse models with manipulated PLIN5 levels specifically in BAT. They found that increasing PLIN5 expression mimicked the effects of cold exposure on BAT, enhancing mitochondrial activity and uncoupled substrate-driven respiration. It was also shown to be essential for maintaining the mitochondrial structure and respiratory function during cold stress.


Further observations linked increased PLIN5 activity in BAT to healthier remodeling of subcutaneous white adipose tissue (WAT), improvements in systemic glucose tolerance, and a decrease in diet-induced hepatic steatosis (a condition involving fatty build-up in the liver).
These findings are significant as they could inform future therapeutic strategies targeting thermogenic adipose tissue for managing type 2 diabetes, obesity, and non-alcoholic fatty liver disease. However, the specific functions of PLIN5 in BAT or WAT have not yet been studied in vivo in humans.  Gallardo-Montejano, V.I., Yang, C., Hahner, L. et al. Perilipin 5 links mitochondrial uncoupled respiration in brown fat to healthy white fat remodeling and systemic glucose tolerance. Nat Commun 12, 3320 (2021).

So, by activating brown fat through cold exposure improvement in glucose levels can be achieved in addition to reduction of fatty deposition in the liver. . .in essence improving visceral fat.  Stay tuned, tomorrow we will review a paper that shows a similar response with estradiol. 

Jason & Rita.