['Fibroblast growth factor (FGF)-21 is a novel regulator of glucose and lipid metabolism. Recently, increased FGF-21 mRNA expression in muscle was found in patients with type 2 diabetes, but the role for FGF-21 in muscle is not well understood. Patients with HIV-infection and lipodystrophy are characterised by various degree of lipid-driven insulin resistance. We hypothesized that muscle FGF-21 mRNA would be altered in HIV patients with lipodystrophy.', 'Twenty-five HIV-infected men with lipodystrophy (LD) and 15 age-matched healthy controls, received an oral glucose tolerance test and a euglycemic-hyperinsulinemic clamp (50 mU/m2/min) combined with 6,6-H2 glucose infusion. Muscle biopsies were obtained and FGF-21 mRNA and glycogen synthase (GS) activity were measured.', 'Subjects with HIV were insulin resistant compared with non-HIV subjects. Compared to controls, HIV subjects demonstrated a twofold increase of plasma FGF-21 from 70.4±56.8 pg/ml vs 109.1±71.8 pg/ml, respectively (p\u200a=\u200a0.04) and an eight-fold increase in muscular FGF-21 mRNA expression (p\u200a=\u200a0.001). Muscle FGF-21 mRNA correlated inversely with the rate of disappearance of glucose during insulin clamp (r\u200a=\u200a-0.54, p\u200a=\u200a0.0009), and the GS fractional velocity in muscle (r\u200a=\u200a-0.39, p\u200a=\u200a0.03), and directly with fasting insulin (r\u200a=\u200a0.50, p\u200a=\u200a0.0022), HOMA-IR (r\u200a=\u200a0.47, p\u200a=\u200a0.004), triglycerides (r\u200a=\u200a0.60. P\u200a=\u200a0.0001), waist-to-hip ratio (r\u200a=\u200a0.51, p\u200a=\u200a0.0001) and limb fat mass (-0.46, p\u200a=\u200a0.004), but not to plasma FGF-21.'] Is expression of fibroblast growth factor-21 in muscle associated with lipodystrophy , insulin resistance and lipid disturbances in patients with HIV?