flavin-adenine-dinucleotide and Thiamine-Deficiency

A combined marginally deficient status of thiamin, riboflavin, vitamin B6 and vitamin C may affect physical performance, but the relative contribution of each vitamin can only be speculated. In a previous study we did not find any effect of restricted intake of vitamin C individually. Therefore, the functional effect of restriction of thiamin, riboflavin or vitamin B6, individually or in conjunction, was investigated.. A double-blind, 2 x 2 x 2 complete factorial experiment on the effects of thiamin, riboflavin and vitamin B6 restriction on physical performance was executed with 24 healthy men. During 11 weeks of low vitamin intake, the subjects were given a daily diet of regular food products providing no more than 55% of the Dutch Recommended Dietary Allowances (RDA) for thiamin, riboflavin and vitamin B6. Other vitamins were supplemented at twice the RDA level.. In vitamin-restricted subjects, blood vitamin levels, erythrocytic enzyme activities and urinary vitamin excretion decreased and in vitro erythrocytic enzyme stimulation increased. Short-time vitamin restriction had no harmful effects on health. A significant overall decrease was observed in aerobic power (VO2-max; 11.6%), onset of blood lactate accumulation (OBLA; 7.0%) and oxygen consumption at this power output (VO2-OBLA; 12.0%), peak power (9.3%), mean power (6.9%) and related variables (p < 0.01). However, the observed performance decrements could not be attributed to marginal deficiency for any of the vitamins studied.. The absence of vitamin-specific effects on performance decrements due to thiamin, riboflavin and vitamin B6 restriction suggests quantitatively similar but non-additive effects of these B-vitamins on mitochondrial metabolism.

Topics: Adult; Double-Blind Method; Energy Metabolism; Erythrocytes; Exercise Test; Flavin-Adenine Dinucleotide; Humans; Lactates; Male; Mitochondria; Oxygen Consumption; Physical Fitness; Riboflavin Deficiency; Thiamine Deficiency; Time Factors; Transketolase; Vitamin B 6 Deficiency

We describe optimized, ultraviolet spectrophotometric procedures for determination of erythrocyte transketolase, glutathione reductase, and aspartate aminotransferase activity, and their activation by their respective coenzymes--thiamine pyrophosphate, flavin-adenine dinucleotide, and pyridoxal-5-phosphate--as tests for vitamin B1, B2, and B6 deficiency. With these procedures we have investigated healthy subjects on normal and vitamin-supplemented diets, and a series of (mainly) alcoholic hospital in-patients. The enzyme procedures described have good precision and can be readily carried out in the routine laboratory. Abnormal transketolase activation correlated well with clinical evidence of vitamin B1 deficiency.

Topics: Aspartate Aminotransferases; Erythrocytes; Flavin-Adenine Dinucleotide; Glutathione Reductase; Kinetics; Pyridoxal Phosphate; Riboflavin Deficiency; Thiamine Deficiency; Thiamine Pyrophosphate; Transketolase; Vitamin B 6 Deficiency; Vitamin B Deficiency

Thiamin and/or riboflavin status have been assessed in rats simultaneously deprived of both vitamins and subsequently repleated with either one or the other in succession. Undernutrition in control rats was found to depress the activity of the erythrocyte enzymes (transketolase and glutathione reductase, respectively) used to assess status. On the other hand, the activity coefficients obtained by in vitro stimulation of the enzymes with their respective missing cofactors were not suppressed. Therefore the activity coefficients were superior indices of thiamin and riboflavin nutriture compared to the enzyme activities. When activity coefficients were used as the indices of vitamin status there did not appear to be interference from the simultaneous deficiency of the alternate vitamin. Apparent interference was encountered when the enzyme activity itself was used as the criteria.

Topics: Animals; Erythrocytes; Flavin-Adenine Dinucleotide; Glutathione Reductase; Male; Rats; Riboflavin Deficiency; Thiamine Deficiency; Thiamine Pyrophosphate; Transketolase

Topics: Animal Nutritional Physiological Phenomena; Animals; Ascorbic Acid Deficiency; Avitaminosis; Body Weight; Erythrocytes; Flavin-Adenine Dinucleotide; Folic Acid Deficiency; Glutathione Reductase; Guinea Pigs; Humans; Liver; Pyridoxine; Rats; Riboflavin; Riboflavin Deficiency; Thiamine Deficiency; Vitamin B 6 Deficiency; Vitamin B Deficiency

Topics: Animal Nutritional Physiological Phenomena; Animals; Body Weight; Erythrocytes; Female; Flavin-Adenine Dinucleotide; Glutathione Reductase; Liver; Male; Organ Size; Rats; Riboflavin; Riboflavin Deficiency; Thiamine Deficiency; Vitamin B 6 Deficiency; Xanthine Oxidase

Topics: Biochemical Phenomena; Biochemistry; Flavin Mononucleotide; Flavin-Adenine Dinucleotide; Gentisates; Homogentisic Acid; Liver; Oxidoreductases; Rats; Research; Riboflavin Deficiency; Spectrum Analysis; Thiamine Deficiency; Ultracentrifugation