Bimodal Behavior of Ascorbic Acid in Musca domestica Larvae

Ascorbic acid (Vitamin C) is an excellent water-soluble dietary antioxidant, well known to protect the biomolecules from oxidative stress-linked damages. It is reported to show a contrary behavior by inflicting pro-oxidant effects under varied, altered circumstances. The present work is an attempt to study the antioxidant and pro-oxidant behavior of ascorbic acid in Musca domestica larvae. Its pro-oxidant properties were tested by exposing the larvae to various concentrations of ascorbic acid. For confirming its oxidant scavenging properties, its effects on the antioxidant enzyme profiles were studied in both the normal and stress-induced M. domestica larvae. Oxidative stress was induced by adding D-Galactose (D-Gal) to the normal food supplement of the larvae. Outcomes of the study demonstrate that ascorbic acid acts as an efficient antioxidant when added in lower concentrations, but at high concentrations, it induces oxidative stress in the larvae, thus acting as a pro-oxidant. At the concentration of 10 mM, ascorbic acid significantly reduced the oxidative stress induced by D-Gal (p < 0.05) and maintained the percent pupal survival and percent eclosion. In conclusion, we suggest that ascorbic acid may function as an antioxidant and pro-oxidant in a concentration-dependent manner under normal physiological conditions.