The X Factor in Liver Metabolism
(Ivanhoe Newswire) – After you eat, a switch occurs in your liver. It goes from producing glucose to storing it in the form of lipids. A new study has found that a protein, Xpbs1, that regulates genes needed for this switch could play a role in metabolic disease.
When your liver makes the switch, a cellular signaling pathway known as the unfolded protein response (UPR) is activated. It is not clear how this pathway contributes to the process, but researchers led by Phillip Scherer at the University of Texas Southwestern Medical Center report that activation of the UPR triggers the expression of Xbp1s.
Using a mouse model, Scherer and colleagues found they could induce changes in liver metabolism just by increasing expression of Xbps1. This was done through a process called refeeding, which is the reintroduction of nutrition after a period of fasting.
The results suggest that Xbps1 plays a critical role in recovering body weight loss from fasting, therefore might be generally involved in conditions of acute body weight loss or gain, such as infectious disease, obesity, or cancer.
Future studies are warranted for a better understanding of the Xbp1s in relation to various pathological conditions, such as insulin resistance, obesity, and cancer.
Source: Journal of Clinical Investigation