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Gout Remedy Report

Gout Remedy Report by Joe Barton

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birds but not with results in mammals where variable effects of DR have been reported. For example, a 10% decrease in blood glucose concentrations in DR rats was associated with a decrease in the glycosylation of proteins, which might be caused by the decreased oxidative stress in DR animals.42,43 Although several studies have firmly established that collagen glycosylation is increased with age, others have failed to demonstrate anything but a cursory relationship between protein cross-linking and glycosylation, either in vivo or in vitro.44-1 As an example, the amount of glycosylated Hb in hummingbirds, which have plasma glucose concentrations in excess of 650 mg/dl, is only 2 to 5%, much lower than that measured in mammals, which have levels ranging from 6 to 8%.48

The reduction in uric acid concentrations, at week 22 in both the DR and AL birds, as a result of allopurinol feeding was associated with an increase in SF value of the pectoralis major muscle. This observation is consistent with our hypothesis that uric acid is an important antioxidant in birds. The reason for the increase in SF values has not been established although the increase in the concentration of the intramolecular cross-link Ps may be associated with an increased level of oxidative stress and glycation. A reduction in the concentration of antioxidants accelerated the formation of glycoxidation products. This finding is supported by the work of others.49-51,52

FIGURE 29.11 Generation of reactive oxygen species (ROS) and associated tissue dysfunction in aves, and the mechanisms utilized against damage by reactive oxygens. O2, molecular oxygen; O2, superoxide anion; OH , hydroxyl radical; H2O2, hydrogen peroxide; GSH/GSSG, reduced/oxidized glutathione; GPx, glutathione peroxidase; NADPH/NADP+, reduced/oxidized nicotinamide adenine dinucleotide phosphate; SOD, superoxide dismutase; CAT, catalase; metal (Fe, Ti, Cu, Cr); AGEs, advanced glycosylated end products.

FIGURE 29.11 Generation of reactive oxygen species (ROS) and associated tissue dysfunction in aves, and the mechanisms utilized against damage by reactive oxygens. O2, molecular oxygen; O2, superoxide anion; OH , hydroxyl radical; H2O2, hydrogen peroxide; GSH/GSSG, reduced/oxidized glutathione; GPx, glutathione peroxidase; NADPH/NADP+, reduced/oxidized nicotinamide adenine dinucleotide phosphate; SOD, superoxide dismutase; CAT, catalase; metal (Fe, Ti, Cu, Cr); AGEs, advanced glycosylated end products.

In conclusion, our investigation has documented that a reduction in uric acid concentration in chickens is associated with increase in oxidative stress, the accumulation of the glycoxidation product Ps, and a decline in the SF value of the pectoralis major muscle. In view of these findings we propose that it is the availability of uric acid in part that regulates the generation of glycoxidation products in the tissues of birds (Figure 29.11). Consequently, a reduction in uric acid concentration accelerates the formation of cross-links and tissue dysfunction. Diet restriction was effective in limiting both the allopurinol-induced increase in oxidative stress as well as the accumulation of Ps. In view of our findings about the toxicity of allopurinol and oxypurinol both the dosage and duration (short vs. extended time scale) and route of administration require additional evaluation. Hemin, while effective at increasing uric acid concentrations, was demonstrated to be an inducer of oxidative stress. The response of the birds to the increase in uric acid was likely masked by hemin-induced oxidative stress and discrimination between the two responses is complicated.

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