Tag Archives: carbonyl stress
Biological aspects of non-enzymatic glycosylation
L. М. Lozinska, H. М. Semchyshyn
Vassyl Stefanyk Precarpathian National University, Ivano-Frankivsk, Ukraine;
е-mail: semchyshyn@pu.if.ua
Non-enzymatic reactions commonly play an ambiguous role in living organism. It is well known that non-enzymatic glycosylation may lead to disruption of the structure and function of biomolecules, thus initiating the development and accompanying different diseases. On the other hand, under certain conditions the products of non-enzymatic glycosylation act as signaling molecules and play an important role in the immune response. Data concerning the influence of non-enzymatic glycosylation and carbonyl stress on living organisms are summarized in the work. The role of reactive carbonyl compounds and reducing carbohydrates in glycation of biomolecules, involvement of non-enzymatic glycosylation in carbonyl stress development and interplay between glycation and free radical processes in living organisms are summarized. The basic ways to prevent glycation and formation of reactive carbonyl compounds that induce carbonyl stress are highlighted. Special attention is paid to the role of the yeast Saccharomyces cerevisiae as a model system to study the glycation processes in vivo.
Defects in antioxidant defence enhance glyoxal toxicity in the yeast Saccharomyces cerevisiae
H. М. Semchyshyn
Vassyl Stefanyk Precarpathian National University, Ivano-Frankivsk, Ukraine;
е-mail: semchyshyn@pu.if.ua
Glyoxal being either exogenous or endogenous compound belongs to reactive carbonyl species. In particular, its level increases under disturbance of the balance of glucose intracellular metabolism as well as of other reductive carbohydrates. Having two carbonyl reactive groups, glyoxal readily enters glycation reaction that results in carbonyl stress development. Investigations of different model systems demonstrate a strong relationship between carbonyl and oxidative stress. However, a possible role of antioxidant system in the organisms’ defence against carbonyl stress is poor understood. In addition, the influence of glyoxal on living organisms is less studied than the effect of such carbonyl reactive species as malonic aldehyde or methylglyoxal. To study a potential role of antioxidant system in organisms’ defence against carbonyl stress induced by glyoxal, the baker’s yeast Saccharomyces cerevisiae was used. It has been found that strains with different defects in the antioxidant defence were more sensitive to glyoxal as compared with parental wild strain. Therefore, the data obtained in the present study confirm the relationship between carbonyl and oxidative stress and reveal the important role of antioxidant system in baker’s yeast defence against carbonyl stress induced by glyoxal.