Circulating progranulin level is associated with visceral fat and elevated liver enzymes: significance of serum progranulin as a useful marker for liver dysfunction.

Progranulin (PRGN) was recently identified as one of the adipokines involved in the development of insulin resistance. Thus, the aim of this study was to explore the importance of PRGN as a novel marker for metabolic diseases in Japanese. A total of 138 subjects were recruited by the Aijinkai Total Health Care Center. Physical examination, blood sample examination and total body CT scan were performed for all participants. Serum PRGN levels were examined in subjects with or without metabolic syndrome and with or without liver enzyme elevation. Association study of serum PRGN levels and regression analysis of the relationship of elevated liver enzymes to representative metabolic parameters were performed. The metabolic syndrome group exhibited older age, and higher BMI, blood pressure, fasting glucose, HbA1c, IRI, HOMA-R, TG, FFA, CRP, AST, ALT, LDH, and ALP, and larger visceral fat area, subcutaneous fat area and visceral fat area/subcutaneous fat area. Serum PRGN concentrations were significantly higher in the metabolic syndrome group than in the non-metabolic syndrome group. Bivariate correlation analysis revealed that serum PRGN concentrations correlated positively and significantly with AST, ALT, LDH, γGTP, ALP, waist circumference and visceral fat area. The group with elevated liver enzymes exhibited higher BMI, blood pressure, IRI, HOMA-R, and PRGN level and larger waist circumference and visceral fat area than the group without them. In logistic regression analysis, visceral fat area and PRGN were significantly predictive of elevated liver enzymes. These results suggest that serum PRGN level as well as visceral fat are associated closely with liver dysfunction.