Serum Leptin Serves as an Inflammatory Activity Marker and Predicts Steroid Response in Autoimmune Hepatitis

Background and aim: Adipocytokines, especially leptin is involved in a wide spectrum of proinflammatory functions, in various tissues. This study was carried out to assess the role of serum leptin in autoimmune hepatitis.

Methods: Serum leptin was analyzed in treatment naïve autoimmune hepatitis (AIH, n = 48) patients and compared with the primary biliary cholangitis (PBC, n = 16), chronic hepatitis C (CHC, n = 16) and healthy controls (n = 15). Serum leptin correlation was assessed on liver function tests, disease activity, T regulatory cells (Tregs), and Th17 cells in the liver biopsies and on steroid treatment response in AIH.

Results: Serum leptin was higher in AIH than in PBC, CHC, and HC {AIH: 335 (106.2-580), PBC: 126 (52-381.2), CH: 67 (3.7-133.5) and HC: 66 (40-157.5) ng/ml; P = 0.001}. In AIH cases; serum leptin correlated with hepatic activity index (r = 0.896; P < 0.001); serum transaminases (aspartate aminotransferases (AST) = 0.615, P < 0.001, alanine aminotransferases (ALT) = 0.551, P < 0.001). It had inverse correlation with Treg cells (P = -0.711, P < 0.001) and positively correlated with Th17 cells (r = 0.650, P < 0.001) in the liver biopsy tissue. High serum leptin was found to be associated with steroid partial or nonresponsiveness at 4 weeks (P = 0.002).

Conclusion: Serum leptin is indicative of higher AIH activity and a reduced number of Tregs cells in liver biopsy tissue. Leptin negative cases have more chances of steroid responsiveness and could help in the selection of AIH cases for appropriate therapy.