Some Aspects of Carbohydrates Metabolism in Biotin-Deficient Rats

Abstract

We reported (1) that amino acid incorporation into liver proteins was reduced markedly in biotin-deficient rats and chicks. In these experiments biotin deficiency was produced on a regime where glucose was the sole source of the carbohydrate. Substitution of 10% of the glucose in the diet by sodium succinate restored amino acid incorporation to the normal level. We suggested that biotin deficiency might be accompanied by an impairment of glucose metabolism resulting in a decreased supply of energy for synthetic processes such as protein synthesis. An exogenous supply of succinate by making itself available for energy production ameliorated this defect.There are conflicting reports (2, 3) about the alleviation of biotin deficiency by sorbitol when it partially replaced glucose in the diet. Using amino acid incorporation ( 1 ) into liver proteins as an index we o h d that sorbitol as well as fructose s h o d a definite beneficial effect. These data and 'the results of a study of oxidative phosphorylaticm in biotin deficiency are given in this paper.Animals and basal diet. Using 35-40 gm weanling male Sprague-Dawley rats, biotin deficiency was produced in 6-7 weeks on a 71% glucose, 20% raw egg-white basal diet which was complete in all nutrients except biotin. Since in biotin deficiency r a b are unable to synthesize ascorbic acid (4) it was included in the basal diet. Normal animals were given parenterally 100 pg of biotin twice a week. Dietary conditions are described under each table.Materials. Fructose, mbitol, ATP, NAD,

Biotin Administration Improves the Impaired Glucose Tolerance of Streptozotocin-Induced Diabetic Wistar Rats.

“…The effect of biotin administration on the glucose tolerance It has been known for many years that biotin deficiency results in an impair ment of glucose utilization (1)(2)(3)(4)(5). In our previous study , insulin secretion in response to an oral glucose load in biotin-deficient male Wistar rats was approxi mately one-sixth less, in concentration terms, than that of pair-fed control rats .…”

Biotin increases glucokinase expression via soluble guanylate cyclase/protein kinase G, adenosine triphosphate production and autocrine action of insulin in pancreatic rat islets☆

“…Farsighted observations of Dakshinamurti [18,19,58] in 1968/1970 suggested that biotin possesses insulin-like effects. In our work, we demonstrated that insulin secretion and insulin-receptor tyrosine kinase PI3K/Akt signalling are involved in the effects of biotin.…”

“…The first evidence that biotin affects glucose metabolism was reported by Dakshinamurti et al [18] in biotin-deficient rats. They observed that glucose tolerance test curves in biotin-deficient rats were significantly higher than the curves of nondeficient rats [18].…”

“…They observed that glucose tolerance test curves in biotin-deficient rats were significantly higher than the curves of nondeficient rats [18]. They further demonstrated that these effects were the result of a reduction in hepatic glucokinase (EC 2.7.1.1) activity [19], and that the stimulatory effect of biotin occurs at the level of transcription [20].…”

Biotin-Stimulated Insulin Secretion in Biotin-Deficient Rats.

“…It has been suggested that biotin deficiency results in an impairment of glucose utilization [1][2][3][4][5]. Our interest was aroused when, in a long-term experiment using Osteogenic Disorder Shionogi (ODS) rats, which have an inherited defect in their ability to synthesize ascorbic acid [6,7], we noticed a decrease in plasma insulin at an early stage in biotin deficiency [8].…”