Oxidative stress, serum biochemistry and DNA damage of Cyprinus carpio communis naturally infected with helminths

Helminth parasites cause severe physiological disturbances and pathological conditions in fish due to generation of different free radicals or reactive oxygen species. These reactive oxygen species cause extensive damage to antioxidant status of fish which is an important and sophisticated defense in fish against the reactive oxygen species. Present study was conducted to analyze the effect of some helminth parasites on antioxidant markers, some biochemical parameters and DNA in the tissues of Cyprinus carpio communis collected from Sukhnag stream. Fish specimens only with Bothriocephalus acheilognathi (n=10), with Pomphorhynchus kashmirensis infection (n=10) and uninfected (n=10) were selected for carrying out the present work. Estimation of antioxidant markers (GSH, glutathione peroxidase, glutathione reductase, glutathione-s-transferase, superoxide dismutase and catalase), lipid peroxidation (LPO), protein content and DNA damage in muscle, intestine, liver and gill tissues was carried out. Serum biochemical constituents like alanine aminotransferase (ALT), aspartate aminotransaminase (AST), cholesterol and triglycerides were also monitored in parasitized and non-parasitized fishes. Analysis of data revealed the decline in GSH content in muscle, intestine and liver whereas increase in enzymatic antioxidants and lipid peroxidation (LPO) in muscle, intestine and liver was noticed in parasitized fishes in comparison to non-parasitized fishes. Significant elevation also observed in ALT, AST, cholesterol and triglycerides in parasitized fishes. DNA degradation was observed in intestinal tissues in parasitized fishes with respect to intestinal DNA of uninfected ones. This study concluded that helminth parasites have a significant impact in fish tissues by inducing oxidative stress which modifies the antioxidant activities, biochemical constituents and damages DNA. The parameters outlined in the present study may be employed as tools in monitoring the health status of fish in culture practices.