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BACKGROUND: Several studies have shown that biotin affects glucose homeostasis. Serum biotin concentrations are lower in subjects with type 2 diabetes than in control subjects. Lymphocyte propionyl-CoA carboxylase (PCC; EC 6.4.1.3) activity has proved to be a sensitive indicator of biotin status that is more accurate than is serum biotin concentration. OBJECTIVE: We studied the activity of PCC, pyruvate carboxylase (PC; EC 6.4.1.1), and acetyl-CoA carboxylase (ACC; EC 6.4.1.2) in type 2 diabetic and nondiabetic subjects. The effect of biotin administration (6.14 micro mol/d) on the activity of these enzymes and on several plasma metabolites was also studied. DESIGN: We compared the activities of carboxylases in circulating lymphocytes from patients with type 2 diabetes (n = 24) with those in circulating lymphocytes from nondiabetic subjects (n = 30). We also assessed the effect of biotin administration for 14 and 28 d on the activity of these enzymes and on the concentrations of several metabolites (type 2 diabetic patients, n = 10; nondiabetic subjects, n = 7). RESULTS: No significant differences in lymphocyte carboxylase activities were found between the type 2 diabetic patients and the nondiabetic subjects. Biotin administration increased the activity of PCC, PC, and ACC in all the subjects. No significant change in glucose, insulin, triacylglycerol, cholesterol, or lactate concentration was observed with the treatment in either the diabetic or the nondiabetic subjects. CONCLUSIONS: The activity of carboxylases does not differ significantly between type 2 diabetic and nondiabetic subjects. Pharmacologic doses of biotin increase lymphocyte PCC, PC, and ACC activities. Copyright © 2004 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Purpose: Hepatitis C (HCV) is the most common liver disease in patients transplanted with hepatocellular carcinoma (HCC) in the West. We examined predictors of HCC recurrence in liver transplant recipients with HCV., Methods: From 1997 to 2006, 53 patients with HCC and HCV underwent liver transplantation. Pre-and post-operative data (including liver biopsies 4 months post-transplant) were collected. Differences between HCC recurrence and non-recurrence groups were detected by Student's t test or chi-square test. Data were analyzed as predictors of HCC recurrence by logistic regression multivariate analysis. Cumulative survival was analyzed by Kaplan-Meier curves and compared by the log-rank test., Results: Eleven of 53 patients (20.8%) developed HCC recurrence at a median interval of 15 months (2 to 55 months). Median Histology Activity Index (HAI) of liver biopsies, AST, and ALT at 4 months were significantly greater in patients with HCC recurrence. Independent predictors of HCC recurrence were HAI ≥ 4 at 4 months, ALT ≥ 100 at 4 months, and vascular invasion. Patients with HCC recurrence had significantly decreased survival., Conclusions: In this preliminary study, Histology Activity Index and ALT at 4 months, as well as vascular invasion, predicted HCC recurrence in liver transplant recipients with HCV.

Biotin is a water-soluble vitamin that acts as a prosthetic group of carboxylases. Besides its role as carboxylase prosthetic group, biotin regulates gene expression and has a wide repertoire of effects on systemic processes. The vitamin regulates genes that are critical in the regulation of intermediary metabolism. Several studies have reported a relationship between biotin and blood lipids. In the present work we investigated the effect of biotin administration on the concentration of plasma lipids, as well as glucose and insulin in type 2 diabetic and nondiabetic subjects. Eighteen diabetic and 15 nondiabetic subjects aged 30-65 were randomized into two groups and received either 61.4 micromol/day of biotin or placebo for 28 days. Plasma samples obtained at baseline and after treatment were analyzed for total triglyceride, cholesterol, very low density lipoprotein (VLDL), glucose and insulin. We found that the vitamin significantly reduced (P=0.005) plasma triacylglycerol and VLDL concentrations. Biotin produced the following changes (mean of absolute differences between 0 and 28 day treatment+/-S.E.M.): a) triacylglycerol -0.55+/-0.2 in the diabetic group and -0.92+/-0.36 in the nondiabetic group; b) VLDL: -0.11+/-0.04 in the diabetic group and -0.18+/-0.07 in the nondiabetic group. Biotin treatment had no significant effects on cholesterol, glucose and insulin in either the diabetic or nondiabetic subjects. We conclude that pharmacological doses of biotin decrease hypertriglyceridemia. The triglyceride-lowering effect of biotin suggests that biotin could be used in the treatment of hypertriglyceridemia.