Effect of turmeric on amelioration of arsenic induced toxicity in grass carp (<i>Ctenopharyngodon idella</i>) fingerlings

The present study evaluated the protective effects of turmeric against arsenic (AS) toxicity in grass carp (Ctenopharyngodon idella) fingerlings. Four experimental groups were maintained for the study: Control (commercial feed only), T1 (turmeric powder @ 1.2% of daily feed), T2 (sodium meta-arsenite @ 3200 µg l-1 + commercial feed), and T3 (sodium meta-arsenite @ 3200 µg l-1 + turmeric powder @ 1.2% of daily feed). The fish fingerlings were randomly assigned to the four groups, each comprising two replicate tanks containing ten fish per tank; and the experiment was conducted over a period of three months. At the end of the experiment, growth performance was assessed, and blood samples were collected for haemoglobin and haematocrit estimation. Liver samples from the Control, T2, and T3 groups were analysed for the expression of metallothionein, tumour necrosis factor-α (TNF-α), and NF-κB p65 genes, which are key markers of detoxification, immunity, and inflammation. Total RNA was extracted andreverse-transcribed into cDNA for gene expression studies. Results showed that arsenic exposure significantly reduced weight gain, haemoglobin, and haematocrit levels, tTrmeric supplementation partly restored these parameters. Arsenic exposure also led to significant upregulation of metallothionein, TNF-α, and NF-κB p65, indicating oxidative and inflammatory stress. Interestingly, turmeric supplementation downregulated the expression of these genes, highlighting its protective role. Overall, the findings of the study indicated that turmeric has a potential ameliorative role in mitigating arsenic-induced toxicity in grass carp. Keywords: cDNA, Gene expression, Haematocrit metallothionein, NF-κB p65, TNF-α