Metabolic derangements linked to hepatic fat in NAFLD

Metabolic derangements and increased homeostasis model assessment index are both associated with hepatic fat in patients with nonalcoholic fatty liver disease, according to recent study findings presented at the 51st European Association for the Study of Diabetes Annual Meeting.

“Abdominal/visceral adiposity is a major risk factor for metabolic syndrome and type 2 diabetes and could be implicated in onset and development of nonalcoholic fatter liver disease (NAFLD),” Chiara Saponaro, a PhD student at the Institute of Clinical Physiology in Italy, said during a presentation. “However, the relative role of visceral fat in the progression of liver damage and dysfunction is still unknown.”

Chiara Saponaro

Saponaro and colleagues evaluated 34 patients without diabetes but with biopsy-proven NAFLD and eight controls to determine the effect of visceral fat on histological liver damage, lipid profile and metabolic alterations.

Researchers measured visceral, subcutaneous and hepatic fat by MRI and plasma concentrations of triglycerides, total cholesterol, free fatty acids and gamma-glutamyl transpeptidase (GGT). De novo lipogenesis index was calculated from plasma free fatty acids, as well as the ratio of unsaturated to saturated fat. Lipolysis, endogenous glucose production, adipose tissue insulin resistance and hepatic insulin resistance also were evaluated.

Of the patients with NAFLD, 24 had a fibrosis score of 1 to 4, and 10 did not have fibrosis. A worse metabolic profile, increased adipose tissue insulin resistance and hemostasis model assessment (HOMA) index were all associated with fibrosis in patients with fibrosis scores of 1 to 4 compared with those without fibrosis and controls (all P < .05 for fibrosis scores 1 to 4 vs. controls). Compared with patients without fibrosis and controls, patients with fibrosis scores of 1 to 4 had higher visceral adiposity (P < .03).

Associations were found between visceral and hepatic fat with adipose tissue insulin resistance, HOMA index and increased plasma levels of triglycerides and de novo lipogenesis (all P < .05). Higher visceral fat and hepatic fat was associated with alterations in free fatty acids.

“In conclusion, in patients with NAFLD, both hepatic fat and visceral fat are associated with metabolic derangements and insulin resistance,” Saponaro said. “The amount of visceral fat that we measured by MRI was also associated with the amount of liver damage.” – by Amber Cox

Reference:

Saponaro C, et al. Abstract #79. Presented at: 51st EASD Annual Meeting; Sept. 14-18, 2015; Stockholm.

Disclosure: Saponaro reports no relevant financial disclosures.