Relevance of gastric pH for protein nitrosation and cardiac protection by sodium nitrite in a myocardial infarction model

• Grant number: 23/07565-5
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2024
• End date: January 31, 2026
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Jose Eduardo Tanus dos Santos
• Grantee: Jose Eduardo Tanus dos Santos
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Oral nitrite treatment showed benefical effects, especially in hypertension. These are partially due to nitrite or nitrate stimulared nitric oxide formation. Our lab has shonw in the last 12 years that such effects depende on acidic gastric pH, which allows the formation of nitrosothiols. This effect is prevented by treatment with omeprazole, an inhibitor of gastric acid secretion. Here, we intend to examine if the protective effects of nitrite in an ischemia-reperfusion animal model are prevented by omeprazole because this drug prevents the gastric formation of nitrosothiols and attenuates cardiac tissue nitrosation, particularly matrix metalloproteinase (MMP)-2 nitrosation, which is critically involved in the degradation of cardiac proteins. This study may reveal how the use of omeprazole may increase the cardiouvascular risk by preventing the protective effects of dietary contents of nitrite and nitrate. (AU)