High-fructose in drinking water initiates activation of inflammatory cytokines and testicular degeneration in rat

Abstract

The increased consumption of high-fructose in diet may contribute to high prevalence of metabolicsyndrome in the world. The influence of high-fructose diet on male reproductive system has beenpoorly documented. In this study, we investigated the effects of dietary high-fructose on the expres-sion of inflammatory cytokines in association with certain testicular proteins and sex hormones in thetestis of rats. Fructose was given to the rats as 20% solution (7.8 mg/kg) in drinking water for15 weeks. Dietary high-fructose caused testicular degeneration, also decreased testicular concentrationof testosterone and right testis absolute weight. This dietary intervention increasediNOSandTNF-amRNAs as well as iNOS, NF-jB, and p-NF-jbproteins, but decreasedIL-10andIL-6mRNAs expressions,in testicular samples of rats. Moreover, testicular TNF-a, IL-1b, and iNOS and plasma IL-1blevels weresignificantly increased in rats fed with fructose. A marked increase in the expression level of IGF-1Rprotein was considered in testicular tissue of fructose-treated rats. The expression intensities of c-kit,claudin-1, and pan-cadherin were comparable in seminiferous tubules of control and fructose-treatedrats. In conclusion, high-fructose intake of rats leads to activation of inflammatory cytokines, which isaccompanied by testicular degeneration. These changes could be responsible for hormonal dysfunc-tion with low intra-testicular testosterone level, which could be relevant to male infertility.