| Free radical oxidation and non-enzymatic glycosylation (glycation) have been found the two most important biochemical side reactions related to the energy metabolism. Polyunsaturated carbonyl toxic substances are their common intermediate, Including malondialdehyde (MDA) is one of the most representative substance, that can cause the carbonyl-amino crosslinking and lead to the aging-associated accumulation of irreversible changes, such as lipofuscin formation. The carbonyl toxification theory of aging suggests that reactive unsaturated aldehydes and ketones produced in lipid peroxidation and glycation can attack the macromolecules and inevitably result in carbonyl-amino reaction with in our body, it may represent the essence of aging process perse. Taurine is a special amino acid that is found in the tissues of most animal species and is the key functional component in a Chinese medicine, Niuhuang. It is wide spreaded and is in the high concentration of cardiac muscle. Taurine is beneficial in a number of patho-physiological processes.This paper discussed the free radical theory of aging, the glycation theory of aging and the carbonyl stress theory of aging, which was based on the biochemistry of age pigment formation. Based on the relationship between carbonyl stress and degenerative diseases, we discussed the molecular mechanisms of taurine on cleanning up the toxicity caused by carbonyl stress and disease. And at the same time, we studied the protection of taurine on the role of human red blood cells.The stduies of this thesis includes the following two parts: 1. Studying the reaction between taurine and MDA using spectrophotometry,spectrofluorometry and liquid chromatography/mass spectrometry (LC/MS) to explore anti-carbonyl stress and the potential pharmacological mechanism of taurine. The results indicated that taurine reacted readily with MDA at supra-physiological condition to form two products, the first one is a lipofuscin-like fluorescent (Ex.396nm/Em.460nm) 1,4-dihydropyridine (Product-1) with an absorption peak at 238,261,390nm, and the second is non-fluorescent enamine with an absorption peak at 275nm (Product-2). Taurine also inhibited the formation of lipofuscin-like fluorescence induced by MDA reacted with bovine serum albumin (BSA). The reaction of taurine with MDA suggested a novel de-carbonylation function of taurine in patho-physiological situations related to aging-related diseases and provided insight into the reaction mechanism of taurine in protecting proteins against carbonyl stress. Based on the aging hypothesis of carbonyl stress, we suggested that taurine effectively reduces carbonyl stress simply due to the amino group in its molecular structure and we propose that this should be the sole mechanism related with taurine's pathophysiological functions in biological system. 2. This paper initially explored the effects of taurine on the erythrocyte hemolysis and membrane protein carbonyl content. the different concentrations of MDA were dealing with red blood cells at the experiment, the results suggested that the rate of hemolysis increased significantly as the increasement of MDA concentration. In the red blood cells of 2mM MDA system, high concentrations of taurine was found to have a inhibition effect. However, there is no effect of taurine on heat-induced hemolysis. Additionlly, taurine repressed the erythrocyte membrane protein carbonyl content induced by MDA. So these experimental data further proved of the anti-carbonyl stress effect of taurine.
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