Vitamin B7 (Biotin)
Description and function
Biotin is a water-soluble vitamin, member of the vitamin B complex. It was also formerly known as vitamin H. Biotin acts as a co-factor for carboxylase enzymes which have important functions in gluconeogenesis (formation of glucose from amino-acids, lactate or the glycerol portion of lipids), in fatty acid synthesis, and in amino acid catabolism.
Deficiency
Biotin deficiency is rare because the vitamin is found in numerous foods and is also synthesized by gut bacteria. It has however been reported in patients on long-term total parenteral nutrition (TPN) not adequately supplemented (nowadays, patients on TPN automatically receive multivitamin supplements), in neonates with bowel disease who were receiving long-term broad spectrum antibiotics (acting against intestinal bacteria). Biotin deficiency has also been experimentally produced by providing diets low in biotin while ingesting large amounts of egg whites (which contain avidin, an antagonist of biotin).
Deficiency may produce digestive symptoms, skin rash, glossitis, somnolence and increase serum cholesterol.
Sources
Biotin is ubiquitous in foods. Best sources include liver, soybean, egg yolks and wholegrain bread and cereals.
Toxicity
None reported.
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Scientific References
Books
Biotin. Mock DM. In: Shils ME, Shike M, Ross AC, Caballero B, Cousins RJ, eds. Modern Nutrition in Health and Disease. 10th ed. Baltimore: Lippincott Williams & Wilkins; 2006:482-497.
Biotin. Camporeale G, Zempleni J. In: Bowman BA, Russell RM, eds. Present Knowledge in Nutrition. 9th ed. Volume 1. Washington, D.C.: ILSI Press; 2006:314-326.
Biotin. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes: Thiamin, Riboflavin, Niacin, Vitamin B6, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, D.C.: National Academy Press; 1998:374-389. (National Academy Press)
Pharmacology of micronutrients. Flodin N., New York: Alan R. Liss, Inc.; 1988.
Scientific articles
Biological functions of biotinylated histones. Kothapalli N, Camporeale G, Kueh A, et al. J Nutr Biochem. 2005;16(7):446-448.
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Biotin administration improves the impaired glucose tolerance of streptozotocin-induced diabetic Wistar rats. Zhang H, Osada K, Sone H, Furukawa Y. J Nutr Sci Vitaminol (Tokyo). 1997;43(3):271-280.
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Biotin biochemistry and human requirements. Zempleni J, Mock DM. J Nutr. Biochem. 1999;10:128-138.
Biotin dependency due to a defect in biotin transport. Mardach R, Zempleni J, Wolf B, et al. J Clin Invest. 2002;109(12):1617-1623.
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Biotin for diabetic peripheral neuropathy. Koutsikos D, Agroyannis B, Tzanatos-Exarchou H. Biomed Pharmacother. 1990;44(10):511-514.
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Biotin regulation of pancreatic glucokinase and insulin in primary cultured rat islets and in biotin-deficient rats. Romero-Navarro G, Cabrera-Valladares G, German MS, et al. Endocrinology. 1999;140(10):4595-4600.
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Biotin status and plasma glucose levels in diabetics. Coggeshall JC, Heggers JP, Robson MC, Baker H. Ann NY Acad Sci. 1985;447:389-392.
Biotin status: which are valid indicators and how do we know? Mock DM. J Nutr. 1999;129(2S Suppl):498S-503S.
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Biotin supplementation reduces plasma triacylglycerol and VLDL in type 2 diabetic patients and in nondiabetic subjects with hypertriglyceridemia. Revilla-Monsalve C, Zendejas-Ruiz I, Islas-Andrade S, et al. Biomed Pharmacother. 2006;60(4):182-185.
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Biotin uptake by human colonic epithelial NCM460 cells: a carrier-mediated process shared with pantothenic acid. Said HM, Ortiz A, McCloud E, Dyer D, Moyer MP, Rubin S. Am J Physiol. 1998;275(5 Pt 1):C1365-1371.
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Brittle nails: response to daily biotin supplementation. Hochman LG, Scher RK, Meyerson MS. Cutis. 1993;51(4):303-305.
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Molecular biology of biotin attachment to proteins. Chapman-Smith A, Cronan JE, Jr. J Nutr. 1999;129(2S Suppl):477S-484S.
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Chromium picolinate and biotin combination improves glucose metabolism in treated, uncontrolled overweight to obese patients with type 2 diabetes. Albarracin CA, Fuqua BC, Evans JL, Goldfine ID. Diabetes Metab Res Rev. 2008;24(1):41-51.
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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. Geohas J, Daly A, Juturu V, Finch M, Komorowski JR. Am J Med Sci. 2007;333(3):145-153.
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Clinical studies on chromium picolinate supplementation in diabetes mellitus--a review. Diabetes Technol Broadhurst CL, Domenico P. Ther. 2006;8(6):677-687.
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Combination of chromium and biotin improves coronary risk factors in hypercholesterolemic type 2 diabetes mellitus: a placebo-controlled, double-blind randomized clinical trial. Albarracin C, Fuqua B, Geohas J, Juturu V, Finch MR, Komorowski JR. J Cardiometab Syndr. 2007;2(2):91-97.
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Determination of the biotin content of select foods using accurate and sensitive HPLC/avidin binding. Staggs CG, Sealey WM, McCabe BJ, Teague AM, Mock DM. J Food Compost Anal. 2004;17(6):767-776.
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Effects of biotin on pyruvate carboxylase, acetyl-CoA carboxylase, propionyl-CoA carboxylase, and markers for glucose and lipid homeostasis in type 2 diabetic patients and nondiabetic subjects. Baez-Saldana A, Zendejas-Ruiz I, Revilla-Monsalve C, et al. Am J Clin Nutr. 2004;79(2):238-243.
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Human biotinidase isn't just for recycling biotin. Hymes J, Wolf B. J Nutr. 1999;129(2S Suppl):485S-489S.
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Human peripheral blood mononuclear cells: Inhibition of biotin transport by reversible competition with pantothenic acid is quantitatively minor. Zempleni J, Mock DM. J Nutr Biochem. 1999;10(7):427-432.
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Inherited defects of biotin metabolism. Baumgartner ER, Suormala T. Biofactors. 1999;10(2-3):287-290.
Low serum biotinidase activity in children with valproic acid monotherapy.Schulpis KH, Karikas GA, Tjamouranis J, Regoutas S, Tsakiris S. Epilepsia. 2001;42(10):1359-1362.
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Lymphocyte propionyl-CoA carboxylase and accumulation of odd-chain fatty acid in plasma and erythrocytes are useful indicators of marginal biotin deficiency small star, filled. Mock D, Henrich C, Carnell N, Mock N, Swift L. J Nutr Biochem. 2002;13(8):462.
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Lymphocyte propionyl-CoA carboxylase and its activation by biotin are sensitive indicators of marginal biotin deficiency in humans. Stratton SL, Bogusiewicz A, Mock MM, Mock NI, Wells AM, Mock DM. Am J Clin Nutr. 2006;84(2):384-388.
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Marginal biotin deficiency during normal pregnancy. Mock DM, Quirk JG, Mock NI. Am J Clin Nutr. 2002;75(2):295-299.
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Marginal biotin deficiency is common in normal human pregnancy and is highly teratogenic in mice. Mock DM. J Nutr. 2009; 139(1):154-157.
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Marginal biotin deficiency is teratogenic in mice and perhaps humans: a review of biotin deficiency during human pregnancy and effects of biotin deficiency on gene expression and enzyme activities in mouse dam and fetus. Mock DM. J Nutr Biochem. 2005;16(7):435-437.
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Marginal biotin deficiency is teratogenic. Zempleni J, Mock DM. Proc Soc Exp Biol Med. 2000;223(1):14-21.
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Serum biotinidase activity in children with chronic liver disease and its clinical significance. Pabuccuoglu A, Aydogdu S, Bas M. J Pediatr Gastroenterol Nutr. 2002;34(1):59-62.
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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. Singer GM, Geohas J. Diabetes Technol Ther. 2006;8(6):636-643.
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Therapeutic evaluation of the effect of biotin on hyperglycemia in patients with non-insulin dependent diabetes mellitus. Maebashi M, Makino Y, Furukawa Y, Ohinata K, Kimura S, Sato T. J Clin Biochem Nutr. 1993;14:211-218.
Treatment of brittle fingernails with biotin, Floersheim GL.. Z Hautkr. 1989;64(1):41-48.
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