Dietary α-lipoic acid alleviates deltamethrin-induced immunosuppression and oxidative stress in northern snakehead (Channa argus) via Nrf2/NF-κB signaling pathway

The goal of the study was to determine the ameliorative effects of dietary alpha-lipoic acid (alpha-LA) on deltamethrin (DEL)-induced immunosuppression and oxidative stress in northern snakehead (Channa argus). The northern snakeheads (15.38 +/- 0.09 g) were exposed to DEL (0.242 mu g/L) and fed with diets supplemented alpha-LA at 300, 600, and 900 mg/kg. After the 28-day exposure test, we obtained the following results: i) alpha-LA alleviates DEL-induced liver injury by reversing the increase of the serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and liver cytochrome P450 enzymes (Cytochrome P450 (cyp)1a and cyp1b) expression levels. ii) alpha-LA can reverse the DEL-induced reduction of serum complement 4 (C4), C3, immunoglobulin M (IgM), and lysozyme (LYS) levels and the increase of liver and intestine nuclear factor kappa B (nf-kappa b) p65, tumor necrosis factor (tnf)-alpha, interleukin (il)-1 beta, il-8, and il-6 gene expressions, while il-10 expression levels showed the opposite result. iii) alpha-LA reversed the reduction of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), glutathione-S-transferase (GST) and glutathione peroxidase (GSH-Px) levels in the liver and intestine induced by DEL, while malondialdehyde (MDA) showed the opposite result. iv) alpha-LA reversed the reduction of Cu/Zn sod, nuclear factor erythroid 2-related factor 2 (nrf2), NAD (P)H: quinone oxidoreductase (nqo)1, and heme oxygenase (ho)-1 antioxidant gene expression levels in the liver and intestine induced by DEL. Therefore, our study indicated that optimal alpha-LA (600 mg/kg) could attenuate DEL-induced toxicity (including liver damage, immunotoxicity, and oxidative stress) in northern snakehead via Nrf2/NF-kappa B signaling pathway. This is the first research that explores the alleviated effects of alpha-LA on DEL-induced toxicity damage in fish. This study provides a positive measure to reduce the toxicity damage caused by DEL to aquatic animals, and provides a theoretical basis for exploring the regulation mechanism of alpha-LA in toxic substances.

Automated summary

The study found that dietary alpha-lipoic acid (alpha-LA) can alleviate immune suppression and oxidative stress induced by deltamethrin (DEL) in northern snakehead. By altering enzyme levels, increasing levels of immune-related substances in serum and liver, regulating gene expression related to oxidative stress, and modulating the Nrf2/NF-kappa B signaling pathway, alpha-LA mitigates DEL-induced toxicity in northern snakehead.