Liver adrenoceptor alpha-1b plays a key role in energy and glucose homeostasis in female mice.

Abstract

The liver plays a major role in glucose and lipid homeostasis and acts as a key organ in the pathophysiology of metabolic diseases. Intriguingly, increased sympathetic nervous system (SNS) activity to the liver has been associated with the development and progression of type 2 diabetes and obesity. However, the precise mechanisms by which the SNS regulates hepatic metabolism remain to be defined. While liver alpha1-adrenoceptors were suggested to play a role in glucose homeostasis, the specific subtypes involved are unknown mainly because of the limitations of pharmacological tools. Here we generated and validated a novel mouse model allowing tissue-specific deletion of alpha-1b adrenoceptor (Adra1b) in hepatocytes to investigate the role of liver ADRA1B in energy and glucose metabolism. We found that selective deletion of Adra1b in mouse liver has limited metabolic impact in lean mice. However, loss of Adra1bin hepatocytes exacerbated diet-induced obesity, insulin resistance and glucose intolerance in female, but not male mice. In obese females, this was accompanied by reduced hepatic gluconeogenic capacity and reprogramming of gonadal adipose tissue with hyperleptinemia. Our data highlight sex-dependent mechanisms by which the SNS regulates energy and glucose homeostasis through liver ADRA1B.