Flavin adenine dinucleotide blood

BBB blood-brain barrier FADH2 reduced flavin adenine dinucleotide... 

A more specific type of chemical assay is based on enzymatic measurement of vitamin co-enzyme activity. This approach is designed to detect a vitamin deficiency in tissues, and is only feasible for those vitamins that serve as co-enzymes. For instance, thiamin depletion in a subject can be diagnosed by measuring the transketolase activity in red blood cells with and without the addition of thiamin pyrophosphate (TPP) in vitro. If TPP increases the activity by more than a given amount, thiamin deficiency is indicated. Similarly, a subnormal level of riboflavin is indicated in tissues if the activity of erythrocyte glutathione reductase is increased after the addition of flavin adenine dinucleotide (FAD). Erythrocyte transaminase activation by pyridoxal-5 -phosphate (PLP) can be measured to establish a deficiency of vitamin B . 

Xanthine oxidase can reduce nitrate to nitrite (Westerfield et al. 1959, Fridovich and Handler 1962). Xanthine oxidase and dissimilatory nitrate reductase share structural similarities. Both are molybdoenzymes and contain flavin adenine dinucleotide and Fe/S clusters (McCord 1985, Mitchell 1986, Payne et al. 1997). Zhang et al. (1998) reported that both purified bovine buttermilk xanthine oxidase and xanthine oxidase-containing inflamed human synovial tissue can generate NO by reducing nitrite in the presence of NADH. This nitrite reductase activity of xanthine oxidase may act as a supplement to the activity of nitric oxide synthase (NOS) to redistribute blood flow to ischaemic tissues when NOS activity is absent. 

Schrijver, J., Speek, A.J., and van den Berg, H., 1991. Flavin adenine dinucleotide in whole blood by HPLC. In Fidanza, F. (ed.) Nutritional Status Assessment A Manual for Population Studies. Chapman fe Hall, London, UK, pp. 251-256. 

The enzyme which replenishes the red blood cell stores of reduced glutathione. It catalyses the following reaction using NADP and flavin adenine dinucleotide (FAD) as cofactors ... 

Until recently the synthesis of flavin adenine dinucleotide had not been studied with purified enzymes from animal tissues. However, the ability of animal tissues to synthesize this coenzyme has been known for a number of years. Klein and Kohn 138) observed formation of flavin adenine dinucleotide in red blood cells in vivo and in vitro, and Trufanov 139) obtained synthesis of flavin adenine dinucleotide in rat tissue slices. Makino et al. 130) obtained formation of flavin adenine dinucleotide from vitamin Ba and ATP in the presence of pig kidney acetone powders, and Yagi 129) reported the synthesis of the coenzyme by the action of acetone powders of rabbit liver or kidney from riboflavin 5 -phosphate, but not riboflavin, and ATP. 

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