Activation of the GP130-STAT3 axis and its potential implications in nonalcoholic fatty liver disease

作者：Min Hae Ki; Mirshahi Faridoddin; Verdianelli Aurora; Pacana Tommy; Patel Vaishali; Park Chun Geon; Choi Aejin; Lee Jeong Hoon; Park Chung Berm; Ren Shunlin; Sanyal Arun J^*

来源：American Journal of Physiology - Gastrointestinal and Liver Physiology, 2015, 308(9): G794-G803.

DOI：10.1152/ajpgi.00390.2014

• NAFLD
• NASH
• IL-6
• palmitate
• gp130
• autophagy
• STAT3
• insulin resistance

The status of the GP130-STAT3 signaling pathway in humans with nonalcoholic fatty liver disease (NAFLD) and its relevance to disease pathogenesis are unknown. The expression of the gp130-STAT3 axis and gp130 cytokine receptors were studied in subjects with varying phenotypes of NAFLD including nonalcoholic steatohepatitis (NASH) and compared with lean and weight-matched controls without NAFLD. Gp130 and its downstream signaling element (Tyk2 and STAT3) expression were inhibited in obese controls whereas they were increased in NAFLD. IL-6 levels were increased in NASH and correlated with gp130 expression (P < 0.01). Palmitate inhibited gp130-STAT3 expression and signaling. IL-6 and palmitate inhibited hepatic insulin signaling via STAT3-dependent and independent mechanisms, respectively. STAT3 overexpression reversed palmitate-induced lipotoxicity by increasing autophagy (ATG7) and decreasing endoplasmic reticulum stress. These data demonstrate that the STAT3 pathway is activated in NAFLD and can worsen insulin resistance while protecting against other lipotoxic mechanisms of disease pathogenesis.

• 出版日期2015-5-1