Mitigating aluminum chloride-induced toxicity in <i>Drosophila melanogaster</i> with peptide fractions from <i>Euphorbia</i> species

This study assessed the antioxidative and protective effects of peptide extracts from selected <i>Euphorbia</i> species on Aluminum Chloride (AlCl₃)-induced toxicity in <i>Drosophila melanogaster. Euphorbia humifusa</i> (EHU), <i>Euphorbia hirta</i> (EHI), and <i>Euphorbia graminae</i> (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 <i>Drosophila melanogaster.</i> 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 <i>Euphorbia humifusa</i> (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 <i>Euphorbia humifusa</i> may shield against the life-threatening effects of free radicals associated with aluminum chloride toxicity.