Effects of curcumin on antioxidative activities and cytokine production in Jian carp (Cyprinus carpio var. Jian) with CCl4-induced liver damage

We investigated the protective effects of curcumin on liver-damaged Cyprinus carpio var. Jian (Jian carp). The carp were fed 0.1%, 0.5%, or 1.0% curcumin for 60 days, then injected intraperitoneally with 30% carbon tetrachloride solution. Liver and blood samples were collected to measure the liver index, serum- and liver-associated enzymes, liver histology, nuclear factor-kappa B (NF-kappa B)/c-Rel, interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), and IL-12 mRNA expression, and the level of NF-kappa B/c-Rel protein in the liver, and for a comet assay. We found that 0.5% and 1.0% curcumin significantly reduced the CCl4-induced increase in the liver index. The comet assay showed that the tail moment, olive tail moment, tail length, and tail DNA% improved in fish pretreated with 0.5 or 1.0% curcumin. CCl4-induced histological changes, including extensive hepatocyte degeneration, indistinct cell borders, nuclear condensation, and karyolysis were clearly reduced after treatment with 0.5% and 1.0% curcumin. Moreover, 0.5% and 1.0% curcumin significantly inhibited the CCl4-induced increase in serum glutamic oxaloacetic transaminase and promoted the restoration of superoxide dismutase in the liver; 1.0% curcumin significantly reduced serum glutamic pyruvic transaminase and lactate dehydrogenase and hepatic malondialdehyde, but significantly increased the total antioxidant capacity and glutathione levels in the liver. The CCl4-induced upregulation of NF-kappa B/c-Rel, IL-1 beta, and TNF-alpha mRNAs and NF-kappa B/c-Rel protein levels was inhibited by 0.5% and 1.0% curcumin, and IL-12 mRNA was reduced by all three doses of curcumin. The effects of curcumin on the liver index, enzymes, histological changes, and cytokines were dose-dependent. Our results indicate that curcumin reduces CCl4-induced liver damage in Jian carp by upregulating antioxidative activities and inhibiting NF-kappa B, IL-1 beta, TNF-alpha, and IL-12 expression. (C) 2014 Elsevier Ltd. All rights reserved.