Middle- and high-molecular weight adiponectin levels in relation to nonalcoholic fatty liver disease

Adiponectin (APN) circulates as high-molecular weight (HMW), medium-molecular weight (MMW), and low-molecular weight (LMW) forms. Nonalcoholic fatty liver disease (NAFLD) is a common cause of chronic liver disease. Currently, the role of LMW, MMW, and HMW APN remains largely unclear in NAFLD.

We examined the variation of these forms and analyzed the related clinical characteristics in NAFLD. A total of 63 male NAFLD patients (mean age: 43.00 ± 6.10 years) and 70 healthy male subjects (mean age: 42.53 ± 7.98 years) were included in the study. Total APN and other clinical characteristics were measured. The changes in HMW, MMW, and LMW APN were determined in NAFLD patients and NAFLD patients on a high-fat diet, and the association between the groups was further analyzed.

Decreased levels of total APN and three APN isoforms were found in NAFLD. Significantly decreased levels of HMW (P < .01) and MMW (P < .001) were observed in NAFLD of high-fat diet patients. In NAFLD patients, height (R = -.270, P = .032) and N-epsilon-(carboxymethyl) lysine (R = -.259, P = .040) significantly correlated with total APN. HMW APN was significantly associated with fasting plasma glucose (R = .350, P = .016), alanine aminotransferase (R = -.321, P = .029), and aspartate aminotransferase (R = -.295, P = .045). Additionally, MMW APN was significantly associated with total cholesterol (R = .357, P = .014) and high-density lipoprotein (R = .556, P < .0001). Low-density lipoprotein (R = -.283, P = .054) was also clearly associated with LMW APN in NAFLD patients.

These results suggest that HMW and MMW APN may be involved in the pathogenesis and progression of NAFLD.