NEPHROPROTECTIVE EFFECT OF TRIBULUS TERRESTRIS ON ATRAZINE EXPOSED FRESHWATER FISH OREOCHROMIS MOSSAMBICUS (W. K. H. Peters, 1852)

Atrazine is used as a selective pre and post-emergence herbicide to control the weeds in asparagus, maize, sorghum, sugarcane, pineapple and paddy fields. It is also used in forestry for non-selective weed control on non-crop areas. Its intensive usage in agriculture has led to the accumulation of atrazine in the soil and water if it exceeds the permissible limits (Vasanth et al., 2013). The impact of atrazine is high toxic which has been resulted in the application of herbicides for varies agricultural crops lead to toxicity in aquatic living organisms. Atrazine rapidly metabolizes in the liver and the kidney and at the same time it rarely leaves any symptoms in the fish tissues. Some experimental studies also documented the alterations of the gill tissues because of their direct contact with water, which allows entering the substance through them into the fish body (Jana Blahova et al., 2014; Solomon et al., 2008; Graymore et al., 2001). Therefore it is most often associated with the degenerative changes in the kidney, gills and also with the alteration in the liver tissues of fishes exposed to atrazine (Jana Blahova et al., 2014; Yang et al., 2010; Fischer-Scherl et al., 1991) Different studies have been reported the atrazine effects on fish, as atrazine affecting the hematological activity, locomotors activity, immune systems, metabolism, oxidative stress, osmoregulatory disturbance and reproduction (Nascimentoc et al., 2012; Tillittd et al., 2012). Bioaccumulation of atrazine in different organs of fish have been noted and thus concluded that the environmental pollutants would affect the fish by entering into and pollutants can enter fish through the gills and skin (Ahsan Khan et al., 2016; Ortiz et al., 2002). Exposing fish to different concentrations of atrazine can in accumulation bring out changes in fish behavior, like unequal movement, better opercular movement, floating on the side, vertical movement, fast swimming, often coming towards the water surface, etc., and such abnormal behavior indicates that herbicides affect the CNS of the fish (Ahsan Khan et al., 2016; Antychowicz et al., 1979). Atrazine is toxic to aquatic animals and most studies have noted that exposure of fish to atrazine results in the biochemical alteration, behavioral abnormalities and structural deformalities and plus stress on reproduction. The alternation the immune system is assessed by quantifying white blood cells (Ahsan Khan et al., 2016; Fu et al., 2013; Solomon et al., 2008). Analysis of biomarkers in aquatic organisms particularly in fish is a validated approach for early warning of chemical exposure (Van der Oost et al., 2003; Osman et al., 2010). During the stress situation fish change due to the inhibition or induction of the enzymes and adapt their metabolic functions (Malarvizhi et al., 2012; Abhijith et al., 2016). Fish are endowed with defensive mechanisms to counteract the impact of reactive oxygen species (ROS) resulting from the metabolism of various chemicals or xenobiotics. Oxidative stress develops when there is an imbalance between pro-oxidants and antioxidants ratio, leading to the generation of ROS. ROS such as hydrogen peroxide (H2O2), superoxide anion O2-and hydroxyl radical (OH·) at supernormal levels can react with biological macromolecules potentially leading to enzyme inactivation, lipid peroxidation (LPO), DNA damage and even cell death but at low concentrations their effects are less pronounced.