Paternal lead exposure induces transgenerational oxidative stress and down-regulation of antioxidant genes in Drosophila melanogaster.

Lead (Pb) is one of the most prevalent environmental toxicants and is of great concern due to its adverse effects. Despite lead's oxidative properties, studies on the transgenerational effects of paternal Pb exposure remain inadequate. This study aimed to evaluate these effects on oxidative stress and the expression of specific genes using the D. melanogaster model. Male fruit flies were fed a normal diet supplemented with lead acetate as the Pb source for 20 consecutive days. The Pb-exposed males were mated with unexposed females, producing F1 offspring. F1 flies were fed a normal diet, and then bred to produce F2; F3 was produced from F2. All F1-F3 generations were kept on a normal diet, with no Pb exposure. Antioxidant parameters, including vitamins A, C, and E; reduced glutathione (GSH); catalase; superoxide dismutase (SOD); malondialdehyde (MDA); and the expression of CAT and SOD1 mRNA, were evaluated. There was a significant (p < 0.05) decrease in antioxidant vitamin levels, GSH content, and catalase and SOD activities across F1-F3 due to exposure to the grandparent (F0). Similarly, a significant (p < 0.05) elevation in MDA levels was observed across the F1-F3 generations due to exposure of the F0 generation. Significant down-regulation of the antioxidant genes CAT and SOD1 was also detected. The findings indicate persistent transgenerational alterations in oxidative stress biomarkers and antioxidant gene expression resulting from paternal Pb exposure. This underscores the importance of studying multiple generations to assess the health and environmental risks posed by pollutants.