A comprehensive in vivo and in silico evaluation of the modulatory effects of a lutein and zeaxanthin antioxidant combination on systemic changes induced by diethylnitrosamine in Drosophila melanogaster

Abstract

Diethylnitrosamine (DEN), a nitrosamine contaminant found in processed foods, tobacco smoke, and other environmental sources, is associated with oxidative toxicity, neurodegeneration, carcinogenesis, and organ injury. Lutein and zeaxanthin (L/Z) are plant-derived xanthophyll carotenoids with antioxidant and anti-inflammatory properties; however, their combined protective effects against DEN-induced toxicity remain insufficiently characterised. This study evaluated the modulatory effects of L/Z against DEN-induced systemic toxicity in Drosophila melanogaster , which shares about 75% of its functional genes with humans, emphasising its value for studying conserved biological pathways using integrated in vivo and in silico approaches. In an initial 10-day dose-response assay, adult flies ( n = 40) of both sexes were exposed to DEN (10, 50, 100, and 200 µM) or L/Z (106, 53, and 35 µM), with untreated controls, to assess survival probability and identify optimal experimental exposure conditions. Using the survival study data, we identified 10 and 200 µM DEN, along with 53 and 35 µM L/Z, as the optimal doses for further experiments. A subsequent co-exposure study examined the protective effects of L/Z (35 and 53 µM) against DEN (10 and 200 µM). DEN reduced survival and induced oxidative and nitrosative stress, antioxidant depletion, impaired acetylcholinesterase (AChE) activity, reduced eclosion, locomotor dysfunction, and histological alterations. Co-treatment with L/Z improved survival and eclosion, restored AChE activity, normalised non-protein thiols (N-PSH), total thiols (T-SH), and glutathione- s -transferase (GST) activity, reduced nitric oxide (NO), and total hydroperoxide (H 2 O 2 ) levels, improved negative geotaxis, and attenuated tissue injury ( p < 0.05 ). Network pharmacology, molecular docking, and ADMET analyses further supported the biological findings by identifying overlapping LZP-DEN targets, implicating glutathione metabolism and conserved redox-regulatory pathways, and showing favourable interactions of lutein and zeaxanthin with GST and AChE. Overall, the findings suggest that combined L/Z supplementation mitigates DEN-induced toxicity through coordinated antioxidant, detoxification, anti-inflammatory, and neuroprotective mechanisms in D. melanogaster .

The authors' abstract, as published at the source. BMC Pharmacology and Toxicology, 2026 · DOI ↗