Pavlovskyi Y. Age-related properties of hydrogen sulfide modulation of gastric mucosa resistance

The dissertation presents a new solution to the current scientific problem of determining the role of hydrogen sulfide modulation in the mechanisms of resistance and adaptive-compensatory reactions of GM in the age aspect under the conditions of damage induction to the stomach barrier function by modification of eicosanoid synthesis, excessive fructose nutrition, combination with stress induction and by administration of compounds that increase endogenous content of hydrogen sulfide (NaHS and H2S-aspirin). Experimental serial studies were performed on 173 white male rats of two age categories (12-14 weeks and 48-56 weeks), each of which was divided into control, groups that were on a high fructose diet, groups with induced aspirin-gastropathy, groups that received H2S-modulation, with and without acute stress. In the study of age-related gastropathy model, age-related differences in the manifestations of adaptive-compensatory reactions of GM were found, under conditions of acute stress induction and modification of cyclooxygenase activity. It was found that hydrogen sulfide modulation using H2S-related aspirin offset the cytolytic effect of classical aspirin on GM. The use of NaHS and H2S-aspirin, as hydrogen sulfide modulation under conditions of long-term 28-day consumption of excessive fructose, reduces the histological index of GM in both adult and old rats, compared with placebo-treated animals. Exposure to H2S-aspirin resulted in decreased CBS and CSE activity in older rats compared to placebo-treated animals and was characterized by a marked preservation of GM integrity. The use of hydrogen sulfide donors was accompanied by a reduction in the signs of damage to the GM during high fructose diet, associated with a decrease in MDA levels and decreased TST activity compared to placebo-treated animals. Age-related differences in changes of oxidative index, which increased with aging, prolonged postprandial hyperglycemia and decreased under conditions of hydrogen sulfide modulation after NaHS and H2S-aspirin administration are proven.