Mitigating aluminum chloride-induced toxicity in Drosophila melanogaster with peptide fractions from Euphorbia species

This study assessed the antioxidative and protective effects of peptide extracts from selected Euphorbia species on Aluminum Chloride (AlCl3)-induced toxicity in Drosophila melanogaster. Euphorbia humifusa (EHU), Euphorbia hirta (EHI), and Euphorbia graminae (EHG) were screened for bioactive peptides. The crude peptide extract and partially purified peptide fractions of all the plants were subjected to preliminary antioxidants activities through 2, 2-diphenyl-1-picrylhyhdrazyl (DPPH), and nitric oxide (NO) scavenging activities. The most active peptide fraction was subjected to biochemical studies using Drosophila melanogaster. Flies were treated with AlCl3 (100 mg/kg diet), peptide fraction (5 and 10 mg/kg diet), and cotreatment of AlCl3 and the fraction, respectively. After treatment, flies were homogenized for the determination of total thiol and Glutathione (non-protein thiol) content, catalase and Glutathione-S-transferase activities, and nitric oxide (nitrite/nitrate) and hydroperoxide levels. The antioxidant screening revealed that the peptide fraction from Euphorbia humifusa (PEHU) was the most significant compared to the control (ascorbic acid). The PEHU (5 and 10 mg/kg diet) maintained the redox status of the flies in the biochemical study. The PEHU significantly counteracted AlCl3-induced reduction in antioxidants (catalase, GST, GSH and Total thiol), increased nitric oxide levels, and acetylcholinesterase activity and prevented behavioral deficits flies. Hence, the peptide fraction of Euphorbia humifusa may shield against the life-threatening effects of free radicals associated with aluminum chloride toxicity.