Abstract
The protective activity of hypotaurine (HTAU) and cysteine sulphinic acid (CSA) on peroxynitrite-mediated oxidative damage has been assessed by monitoring different target molecules, i.e. tyrosine, dihydrorhodamine-123 (DHR) and glutathione (GSH). The inhibition of tyrosine oxidation exerted by HTAU and CSA both in the presence and the absence of bicarbonate can be ascribed to their ability to scavenge hydroxyl (•OH) and carbonate (CO3•−) radicals. HTAU and CSA also reduce tyrosyl radicals, suggesting that this repair function of sulphinates might operate as an additional inhibiting mechanism of tyrosine oxidation. In the peroxynitrite-dependent oxidation of DHR, the inhibitory effect of HTAU was lower than that of CSA. Moreover, while HTAU and CSA competitively inhibited the direct oxidation of GSH by peroxynitrite, HTAU was again poorly effective against the oxidation of GSH mediated by peroxynitrite-derived radicals. The possible involvement of secondary reactions, which could explain the difference in antioxidant activity of HTAU and CSA, is discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.