Free Radical Scavenging Activity of Boron and Vitamin C in Nitrite-Induced Hemoglobin Oxidation Model: In vitro and in vivo Studies

Abstract

Objective: To investigate the dose-response relationship of the free radical-scavenging activities of boron and vitamin C in nitrite-induced hemoglobin oxidation in vitro and in vivo. Method: Different concentrations of boron and vitamin C were added to a hemolysate challenged with nitrite to induce methemoglobinemia (MetHb), and the most effective dose of boron and vitamin C was used before and after different intervals of inducing Hb oxidation, and the production of MetHb was monitored using a spectrophotometer. The effective doses of boron and vitamin C, alone and in combination, were administered to rats before challenging them with an oral dose of 100 mg/kg sodium nitrite. Results: In vitro results indicated that different concentrations of boron and vitamin C attenuated MetHb formation, with the maximum effect achieved at 0.08mg/L and 10mg/L, respectively. Moreover, when these doses were used at different time intervals, a maximum effect was achieved when added 10 min before nitrite. The in vivo results demonstrated a significant reduction in methemoglobin formation in rats treated with boron and vitamin C alone. The hematological markers were not changed except for the platelet levels, which increased in the boron-treated and combination groups. The monocyte-to-lymphocyte ratio decreased significantly in all treatment groups compared with the positive control group. Conclusion: Boron protects against Hb oxidation induced by nitrite, and a potentiated effect has been achieved with the combination of vitamin C.