cytellin and Fatty-Liver

We investigated how liver fat content (LFC) influences cholesterol metabolism by quantifying liver fat using proton magnetic resonance spectroscopy and by measuring the serum concentrations of lathosterol, a marker of cholesterol synthesis, and sitosterol and campesterol, two markers of cholesterol absorption. We also evaluated whether this relationship could be modified by statin therapy. The study was conducted in 263 patients with type 2 diabetes, 137 of whom (52.0%) received statin therapy.. One hundred and sixty-five patients (62.7%) had steatosis (LFC>5.5%). We performed specific analyses in patients without statin therapy and in patients treated with statin therapy. In both groups, the lathosterol to cholesterol ratio correlated positively with LFC, and in multivariate analysis, the lathosterol to cholesterol ratio was associated with LFC independently of age, gender and BMI. Sitosterol and campesterol concentrations were not associated with LFC.. Our study suggests that in patients with type 2 diabetes, LFC is associated with an increase in cholesterol synthesis that is independent of obesity or diabetes mellitus. Statin therapy does not modify this relationship.

Topics: Aged; Biomarkers; Cholesterol; Diabetes Mellitus, Type 2; Dyslipidemias; Fatty Liver; Female; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Linear Models; Liver; Magnetic Resonance Spectroscopy; Male; Middle Aged; Multivariate Analysis; Non-alcoholic Fatty Liver Disease; Phytosterols; Risk Factors; Sitosterols; Treatment Outcome

Non-alcoholic fatty liver disease (NAFLD) is associated with impaired glucose and lipoprotein metabolism. However, the metabolism of cholesterol in NAFLD remains unexplored. We investigated how fatty liver influences cholesterol metabolism in 242 non-diabetic subjects.. Liver fat content was measured with proton magnetic resonance spectroscopy. Cholesterol metabolism was assayed with serum non-cholesterol sterols, surrogate markers of cholesterol synthesis and absorption. The analyses were performed with gas-liquid chromatography.. A total of 114 subjects had NAFLD and 128 subjects had normal liver fat content. Non-cholesterol sterols reflecting cholesterol synthesis (cholestenol, desmosterol, and lathosterol) were higher, and those reflecting cholesterol absorption (cholestanol and plant sterols) were lower in subjects with NAFLD than in controls, independent of body mass index. Liver fat content was positively associated with markers of cholesterol synthesis (r = from 0.262 to 0.344, p < 0.001 for all) and inversely associated with markers of cholesterol absorption (r = from -0.299 to -0.336, p < 0.001 for all). In the entire study group, synthesis and absorption markers were interrelated, indicating that the homeostasis of cholesterol metabolism was maintained. LDL cholesterol was similar in the two groups.. We demonstrated that although LDL cholesterol concentrations are unchanged, cholesterol metabolism in NAFLD is characterized by increased synthesis and diminished absorption of cholesterol. These changes are associated with liver fat content independent of body weight.

Topics: Adult; Aged; Body Mass Index; Case-Control Studies; Cholesterol; Cholesterol, Dietary; Cholesterol, LDL; Fatty Liver; Female; Humans; Insulin; Intestinal Absorption; Liver; Magnetic Resonance Spectroscopy; Male; Middle Aged; Non-alcoholic Fatty Liver Disease; Obesity; Sitosterols; Young Adult