Pharmacological effects of biotin

Combination of chromium and biotin improves coronary risk factors in hypercholesterolemic type 2 diabetes mellitus: a placebo-controlled, double-blind randomized clinical trial

Dyslipidemia, often found in type 2 diabetes mellitus (T2DM) patients, plays an important role in the progression of cardiometabolic syndrome. Two essential nutrients, chromium and biotin, may maintain optimal glycemic control. The authors report here a randomized, double-blind placebo-controlled trial (N=348; chromium picolinate and biotin combination [CPB]: 226, placebo: 122; T2DM participants with hemoglobin A1c [HbA1c] >or=7%) evaluating the effects of CPB on lipid and lipoprotein levels. Participants were randomly assigned (2:1 ratio) to receive either CPB (600 microg chromium as chromium picolinate and 2 mg biotin) or a matching placebo once daily for 90 days. Statistical analyses were conducted in all eligible participants. Subsequent supplemental analyses were performed in T2DM participants with hypercholesterolemia (HC) and in those using stable doses of statins. In the primary analysis, CPB lowered HbA1c (P<.05) and glucose (P<.02) significantly compared with the placebo group. No significant changes were observed in other lipid levels. In participants with HC and T2DM, significant changes in total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels and atherogenic index were observed in the CPB group (P<.05). Significant decreases in LDL-C, total cholesterol, HbA1c , and very low-density cholesterol levels (P<.05) were observed in the CPB group taking statins. CPB treatment was well tolerated with no adverse effects, dissimilar from those associated with placebo. These data suggest that intervention with CPB improves cardiometabolic risk factors.

Chromium Picolinate and Biotin Combination Reduces Atherogenic Index of Plasma in Patients with Type 2 Diabetes Mellitus: A Placebo-Controlled, Double-Blinded, Randomized Clinical Trial

BACKGROUND

The atherogenic index of plasma (AIP), defined as logarithm [log] of the ratio of plasma concentration of triglycerides to high-density lipoprotein (HDL) cholesterol, has recently been proposed as a predictive marker for plasma atherogenicity and is positively correlated with cardiovascular disease risk. The nutrient combination of chromium picolinate and biotin (CPB) has been previously shown to reduce insulin resistance and hyperglycemia in patients with type 2 diabetes (T2DM).

METHODS

Thirty-six moderately obese subjects with T2DM and with impaired glycemic control were randomized to receive CPB or placebo in addition to their oral hyperglycemic agents for 4 weeks. Measurements of blood lipids (including ratio of triglycerides to HDL cholesterol), fructosamine, glucose, and insulin were taken at baseline and after 4 weeks.

RESULTS

At the final visit, the active group had a significantly lower AIP compared to the placebo group (P < 0.05). A significant difference in triglyceride level (P < 0.02) and the ratio of low-density lipoprotein (LDL) to HDL cholesterol (P < 0.05) was also observed between the groups at the final visit. In the active group, the changes in urinary chromium levels were inversely correlated with the change in AIP (P < 0.05). Urinary chromium levels were significantly increased in the CPB group. In the CPB group, glucose levels decreased at 1 hour and 2 hours and glucose area under the curve and fructosamine level were significantly decreased. Ratios of total to HDL cholesterol, LDL to HDL cholesterol, and non-HDL to HDL cholesterol were significantly decreased between the treatments at final visit. No significant adverse events were observed in the CPB or placebo groups.

CONCLUSIONS

These results suggest that the combination of chromium picolinate and biotin may be a valuable nutritional adjuvant therapy to reduce AIP and correlated CVD risk factors in people with T2DM.

The effect of chromium picolinate and biotin supplementation on glycemic control in poorly controlled patients with type 2 diabetes mellitus: a placebo-controlled, double-blinded, randomized trial

BACKGROUND

Preclinical studies have shown that the combination of chromium picolinate and biotin significantly enhances glucose uptake in skeletal muscle cells and enhances glucose disposal. The present pilot study was conducted to determine if supplementation with chromium picolinate and biotin can improve glycemic control in patients with type 2 diabetes mellitus with suboptimal glycemic control despite use of oral antihyperglycemic agents.

METHODS

Forty-three subjects with impaired glycemic control (2-h glucose >200 mg/dL; glycated hemoglobin >or=7%), despite treatments with oral antihyperglycemic agents, were randomized to receive 600 microg of chromium as chromium picolinate and biotin (2 mg/day) (Diachrome(, Nutrition 21, Inc., Purchase, NY) in addition to their prestudy oral antihyperglycemic agent therapy. Measurements of glycemic control and blood lipids were taken at baseline and after 4 weeks.

RESULTS

After 4 weeks, there was a significantly greater reduction in the total area under the curve for glucose during the 2-h oral glucose tolerance test for the treatment group (mean change -9.7%) compared with the placebo group (mean change +5.1%, P < 0.03). Significantly greater reductions were also seen in fructosamine (P < 0.03), triglycerides (P < 0.02), and triglycerides/ high-density lipoprotein cholesterol ratio (P < 0.05) in the treatment group. No significant adverse events were attributed to chromium picolinate and biotin supplementation.

CONCLUSIONS

This pilot study demonstrates that supplementation with a combination of chromium picolinate and biotin in poorly controlled patients with diabetes receiving antidiabetic therapy improved glucose management and several lipid measurements. Chromium picolinate/ biotin supplementation may represent an effective adjunctive nutritional therapy to people with poorly controlled diabetes with the potential for improving lipid metabolism.

Improved liquid chromatography methods for the separation and quantification of biotin in NIST standard reference material 3280: multivitamin/multielement tablets

Two independently developed liquid chromatography (LC) methods for the quantitative determination of biotin in multivitamin/multielement tablets (NIST Standard Reference Material 3280 (SRM 3280)) are described. The methods use distinctly different tablet extraction solvents (methanol vs 1.5% aqueous formic acid) and analyte detection principles (mass spectrometry (MS) versus evaporative light-scattering detection (ELSD)) to ensure quantitative reliability. The use of different extraction and detection procedures allows cross-validation of the methods and enhances confidence in the final quantitative results. Both methods yield highly comparable results for the mean level of biotin (LC/MS = 26.5 mg/kg +/- 0.3 mg/kg (n = 12); LC/ELSD = 24.7 mg/kg +/- 1.7 mg/kg (n = 12)) in SRM 3280, yet the methods differ considerably in their analytical characteristics. The isotope-dilution LC/MS method exhibits excellent linearity from 0.02 ng to 77 ng biotin on-column with a method limit of detection (LOD) and limit of quantification (LOQ) of 0.02 ng (S/N > 3) and 0.06 ng (S/N > 10) biotin on-column, respectively. The LC/ELSD method exhibits good linearity from 155 ng to 9900 ng biotin on-column with a method LOD and LOQ of 155 ng (S/N > 3) and 310 ng (S/N > 10) biotin on-column, respectively. Method performance data indicates that the LC/MS method is analytically superior to the LC/ELSD method; however, either method in combination with SRM 3280 should provide quality assurance, accuracy, and traceability for biotin levels in multivitamin/multielement dietary supplements.

Asymmetric Synthesis of Highly Functionalized Tetrahydrothiophenes by Organocatalytic Domino Reactions

A simple approach for the formation of optically active highly functionalized tetrahydrothiophenes, which might find important use in biochemistry, pharmaceutical science, and nanoscience is presented. Development of new organocatalytic Michael-aldol domino reactions is outlined, and with the appropriate choice of additives it is possible to control the regioselectivity of these domino reactions, yielding diastereomerically pure (tetrahydrothiophen-2-yl)phenyl methanones or tetrahydrothiophene carbaldehydes in good yields and with excellent enantioselectivities up to 96% ee. The stereochemical outcome of these reactions is investigated, and the mechanism of these organocatalytic domino processes is presented.

Biotin supplementation reduces plasma triacylglycerol and VLDL in type 2 diabetic patients and in nondiabetic subjects with hypertriglyceridemia

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.

Mitochondrial function and toxicity: role of the B vitamin family on mitochondrial energy metabolism

The B vitamins are water-soluble vitamins required as coenzymes for enzymes essential for cell function. This review focuses on their essential role in maintaining mitochondrial function and on how mitochondria are compromised by a deficiency of any B vitamin. Thiamin (B1) is essential for the oxidative decarboxylation of the multienzyme branched-chain ketoacid dehydrogenase complexes of the citric acid cycle. Riboflavin (B2) is required for the flavoenzymes of the respiratory chain, while NADH is synthesized from niacin (B3) and is required to supply protons for oxidative phosphorylation. Pantothenic acid (B5) is required for coenzyme A formation and is also essential for alpha-ketoglutarate and pyruvate dehydrogenase complexes as well as fatty acid oxidation. Biotin (B7) is the coenzyme of decarboxylases required for gluconeogenesis and fatty acid oxidation. Pyridoxal (B6), folate and cobalamin (B12) properties are reviewed elsewhere in this issue. The experimental animal and clinical evidence that vitamin B therapy alleviates B deficiency symptoms and prevents mitochondrial toxicity is also reviewed. The effectiveness of B vitamins as antioxidants preventing oxidative stress toxicity is also reviewed.