Nano-curcumin mitigates aluminum oxide nanoparticle toxicity in Nile tilapia through antioxidant and immune modulation

Abstract Our study investigated the toxicological effects of aluminum oxide nanoparticles (Al 2 O 3 -NPs) and the potential protective role of dietary nano-curcumin (N-CUR) in juvenile Oreochromis niloticus (30.39 ± 0.05 g) under controlled experimental conditions. It was hypothesized that N-CUR could mitigate the adverse impacts of Al 2 O 3 -NPs on growth, biochemical, oxidative, and histopathological parameters. A total of 180 O. niloticus were divided into six groups: a control group, two N-CUR-supplemented diets (40 and 50 mg/kg), an Al 2 O 3 -NP-exposed group (10 mg/L), and two co-treated groups receiving both treatments for 4 weeks. Growth performance, biochemical, immunological, antioxidant, and histopathological parameters were assessed. Exposure to Al 2 O 3 -NPs markedly reduced growth indices and survivability while elevating ALT activity and pro-inflammatory gene expression (TNFα, IL1β, MT). Antioxidant genes (CAT and SOD) were significantly downregulated, and histopathological lesions, including hyperemia, hyperplasia, and vacuolization, were evident. Conversely, N-CUR co-supplementation significantly improved growth (14.5%–46.1%), feed efficiency (46.7%–74.1%), and specific growth rate (219%–605%). It also reduced ALT (37.7%–40.1%) and enhanced albumin, A/G ratio, and IgM levels ( P < 0.05). Overall, these findings indicate that dietary N-CUR attenuated Al 2 O 3 -NP-induced oxidative and inflammatory stress, thereby improving the biochemical and histological health of O. niloticus . Hence, these outcomes provide a mechanistic proof of dietary N-CUR’s protective role against toxicity induced by Al 2 O 3 -NPs, indicating the need for further investigation in exposure scenarios that are relevant to the environment.