Ascorbic acid glutathione and

It is not clear whether V(V) or V(IV) (or both) is the active insulin-mimetic redox state of vanadium. In the body, endogenous reducing agents such as glutathione and ascorbic acid may inhibit the oxidation of V(IV). The mechanism of action of insulin mimetics is unclear. Insulin receptors are membrane-spanning tyrosine-specific protein kinases activated by insulin on the extracellular side to catalyze intracellular protein tyrosine phosphorylation. Vanadates can act as phosphate analogs, and there is evidence for potent inhibition of phosphotyrosine phosphatases (526). Peroxovanadate complexes, for example, can induce autophosphorylation at tyrosine residues and inhibit the insulin-receptor-associated phosphotyrosine phosphatase, and these in turn activate insulin-receptor kinase. 

Freebaim noted a decrease in oxygen uptake of plant and bovine liver mitochondria that was reversible by glutathione and ascorbic acid. The activity of some mitochondrial enzymes, including succinic dehydrogenase and cytochrome oxidase, has been found to be susceptible to ozone. 

Zygulska-Mach, H., and Mach, Z. (1975). The effect of gamma rays on glutathion and ascorbic acid content in rabbit lenses [in German]. Klin. Monatsbl. Augenheilkd. 166, 50-55. 

Riederer, P., Strolin-Benedetti, M., Dostert, P., Sofi6, E., Heuschneider, G. and Guffroy, C. (1987) Do glutathione and ascorbic acid play a role in the neurotoxicity of 1-... 

Riederer, P., Sofic, E., Rausch, W.D., Schmidt, B., Reynolds, G.P., Jellinger, K. and Youdim, M.B.H. (1989c) Transition metals, ferritin, glutathione, and ascorbic acid in parkinsonian brains. J. Neurochem. 52 515-520. 

Ciesielski, W. Simultaneous spectrophotometric determination of cysteine, glutathione, and ascorbic acid with the use of the iodine-azide reaction. Chem. Anal. 1986, 31, 99-103. 

Golan-Goldhirsh and colleagues (71,72) report that sodium bisulfite, reduced glutathione, and ascorbic acid caused a 50% inactivation of mushroom polyphenol oxidase after 28, 106, and 130 min, respectively, at 5 mM concentration. Dithiothreitol was a more effective inhibitor, causing 50% inactivation at 0.1 mM after only 70 min. 

Stern, H., Timonen, S. Position of the cell nucleus in pathways of hydrogen transfer Cytochrome c, flavoproteins, glutathione and ascorbic acid. J. gen. Physiol. 38, 41-52 (1954)... 

Shklar, G., Schwartz, J., Trickier, D., and Cheverie, S. R., 1993, The effectiveness of a mixture of p-carotene, a-tocopherol, glutathione, and ascorbic acid for cancer prevention, Nutr. Cancer 20 145-151. 

Supplement contains o-glucose, L-glutamine, penicillin, and streptomycin sulfate. FVM supplement contains glutathione and ascorbic acid (Specialty Medium, Lavallette, NJ)... 

BS Winkler, SM OrseUi, TS Rex. The redox couple between glutathione and ascorbic acid a chemical and physiological perspective. Free Rad Biol Med 17 333-349, 1994. 

Riederer P, Sofic E et al. (1989) Transition metals, ferritin, glutathione, and ascorbic acid in parkinsonian brains. J Neurochem. 52 515-520. 

Increased protein and decreased glutathione and ascorbic acid levels in aqueous humour (note this is prior to onset of clinical signs)... 

Catalytic solutes may be subdivided into (i.) non-colloidal catalysts, and (ii.) colloidal catalysts or enzymes. The first subgroup includes soluble catalysts of low molecular weight, such as electrolytes, glutathione and ascorbic acid the second group includes the vast assortment of enzymes that in variety and importance dominate the biochemistry of catalysis. 

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