Protective Effects of Astaxanthin on Nephrotoxicity in Rats with Induced Renovascular Occlusion.

Abstract

Various effects of Astaxanthin were shown in the studies, including its antioxidant, anti-inflammatory, anti-tumor and immunoregulatory effects. The aim of this study was to evaluate the beneficial effects of Astaxanthin on renovascular occlusion induced renal injury and to investigate the possible mechanisms. The rats were randomly assigned into three groups as follows: Group 1: control group (n=12), Group 2: renal ischemia-reperfusion injury group (n=12), Group 3: renal ischemia-reperfusion + asthaxantine treated group (n=12). The control group and the renal ischemia-reperfusion group were given 2cc/kg/g olive oil for 7 days before establishing ischemia to renal tissue. Astaxanthin dissolved in olive oil was given orally to the renal ischemia+astaxanthin group for 7 days before inducing renal ischemia. Caspase-(3, 8, 9), GSH, SOD, Total Thiol, TNF-α, IL-6, 8-OHdG were evaluated in each group. Renal IRI was verified by analysing the pathological changes of renal tissues and the renal functions after renal reperfusion. Much less renal tubular damage was determined in the IRI+ASX group in comparison to the IRI group. Caspase-8, -9 and -3 immunoreactivity was observed to be minimal in the control group. Apoptosis was observed to be significantly reduced in the IRI + ASX group with respect to the IRI group and close to the level of the control group (p <0.05). Caspase-3 levels of tissue samples were significantly increased in the IRI group compared to the other groups, but significantly lower in the IRI+ASX group with respect to the IRI group (p<0.05). The TOS and OSI levels, indicating increased oxidative stress, were significantly lower in the IRI+ASX group with respect to the IRI group (p <0.001), but still higher than the control group (p <0.001). In addition to GSH, SOD and Total Thiol levels, TAS levels were also significantly higher in the IRI + ASX group in comparison to the IRI group (p <0.05). TNF-α, IL-6, lipid hydroperoxide, AOPP and 8-OHdG levels were lower in the IRI+ASX group than the IRI group (p <0.001). MPO, IL-6, TNF-α levels, representing the parameters indicating neutrophil infiltration and inflammation of the renal tissues, significantly increased in the IRI group with respect to the other groups (p <0.005). When all the data obtained in our study were evaluated, ASX was determined to prevent renal damage due to renovascular occlusion to a great extent, through complex mechanisms involving antioxidant, anti-inflammatory and antiapoptotic effects. Biochemical, histological and oxidative stress parameters were improved due to ASX.