Co-Exposure of N-Methyl-N-Nitrosourea and Benzo[A]Pyrene Elicits Toxicity in Drosophila Melanogaster.

Human exposure to environmental pollutants is multi-variant with resultant interactive effects such as oxidative stress, and it's associated with several disease pathogenesis. This study aimed to assess the effects on behavioural pattern, redox status, mitochondrial metabolic rate, and possible alterations in the gut, fat body, and ovary tissues in Drosophila melanogaster exposed to N-methyl-N-nitrosourea (NMU) and Benzo[a]pyrene (BaP). The fruit flies, 1-3 days old, were distributed into the Control group, which received a [methanol and ethanol mixture (1:7)]-containing diet, and other groups received diets containing NMU (1 and 2 mM) and BaP (0.4 and 0.8 mM) for 5 days. Results showed that NMU and BaP exposure caused a significant decrease in the rate of survival of the flies. Altered behavioral pattern was observed as an eclosion rate (78%,) and the locomotor capacity was decreased. NMU and BaP caused a reduction in mitochondrial metabolic rate, and levels of total H2O2, NO, lipid peroxidation, and protein carbonyl content were observed to increase significantly; however, the total sulfhydryl and Non-protein thiols, as well as the activities of catalase, glutathione-s-transferase, and acetylcholinesterase, were decreased relative to control. Histo-architecture of gut, fat body, and ovarian tissues was negatively altered, alongside phenotypic changes such as enlargement of the eyes and abnormal morphology of the ovaries. Taken together, NMU and BaP induced toxicity via oxidative stress and disruption of redox status, behavioural deficits, and developmental abnormalities, suggesting Drosophila melanogaster as a suitable organism for assessing the toxicity of environmental carcinogens.