High-fructose consumption suppresses insulin signaling pathway accompanied by activation of macrophage and apoptotic markers in rat testis

Dietary high-fructose may cause metabolic disturbances; however, its effect on the reproductive system is little understood. The insulin signaling pathway is critical in testicular development, maintenance of microcirculation and spermatogenesis. Therefore, in this study, we aimed to investigate the impact of dietary high-fructose on insulin signaling pathway as well as macrophage and apoptotic markers in testicular tissue of rats. Fructose was administered to male Wistar rats as a 20% solution in drinking water for fifteen-week. Gene expression of ir-β, irs-1, irs-2, pi3k, akt, mtor, and enos in the testicular samples was determined by real-time PCR. Protein expression of IR, IRS-1, IRS-2, PI3K, Akt, phospho-Akt (p-Akt), mTOR, eNOS, phospho-eNOS (p-eNOS), and GLUT5 was established by analysis of Western Blot. Testicular expression of occludin, CD163, CD68, caspase-8, and caspase-3 was analyzed by using immunohistochemical assay. Testicular level of fructose was measured by colorimetric method. Dietary high-fructose decreased mRNA expressions of irs-1, irs-2, pi3k, and mtor in the testicular tissue of rats. Also, this dietary intervention impaired protein expressions of IR, IRS-1, IRS-2, PI3K, p-Akt, mTOR, eNOS, and p-eNOS as well as p-Akt/Akt and p-eNOS/eNOS ratios in the testis of rats. However, a high-fructose diet increased the expression of CD163, CD68, caspase-8 and caspase-3, but decreased that of occludin, in the testicular tissue of rats. The high-fructose consumption in rats suppresses testicular insulin signaling but activates macrophages-related factors and apoptotic markers. These changes induced by dietary fructose could be related to male reproductive dysfunction.

GABAergic Alterations in the Rat Testis after Methamphetamine Exposure

Gamma-aminobutyric acid (GABA), GABA-A receptors and GABA transporter 1 (GAT1) were reported to be involved in the proliferation of Leydig cells, testosterone production and spermatogenesis. Since methamphetamine (METH) has been reported to have adverse effects on testis and its functions, the aim of this study was therefore to determine the changes of GABAergic activity in testis after METH exposure. Male Sprague-Dawley rats were divided into control, acute binge (AB-METH), escalating dose (ED METH) and escalating dose-binge (ED-binge METH) groups. After sacrifice, rat testes were removed and used to estimate GABA concentration and the expression of GABA-A receptor, GAD1, GAD2 and GAT1 genes by using HPLC and RT-PCR, respectively. The GABA concentration was significantly increased in all METH-administrated groups. In addition, significant increases of GABA-A α1 receptor and GAD1 genes expression were found in the ED-binge METH group. Gene expressions of GAT1 were numerically decreased in all METH-administrated rats and reached significant in the ED METH group. These results indicated a compensatory upregulation of GABA production and its functions in testis after METH exposure. Thus, these changes might represent a homeostatic response of GABAergic to the adverse effects of METH.

The effects of melatonin and colchicine on ischemia-reperfusion injury in experimental rat testicular torsion model

PURPOSE

The aim of the present study is to investigate the efficiency of colchicine and melatonın in an experimental rat testicular torsion model in the light of histological and biochemical data.

METHODS

A total of 34 Wistar albino male rats were randomly divided into 5 groups as: Group C (control, n=6), Group S (sham; underwent only left scrotal exploration, n=7), Group TD (torsion and detorsion; 6h of ischemia and 7days of reperfusion, n=7), Group TD/M (TD+Melatonin; 6h of ischemia and 7days of reperfusion and 7days of 17mg/kg intraperitoneal melatonin per day, n=7), group TD/Col (TD+Colchicine; 6h of ischemia and 7days of reperfusion and 7days of 1mg/kg oral colchicine per day, n=7). Histopathologic evaluation of seminiferous tubule deterioration was performed by Johnsen's scoring system. Total antioxidant status (TAS), total oxidant status (TOS), IL-6, TNF alpha levels were analyzed in each group.

RESULTS

The histopathologic scores, total antioxidant status (TAS), total oxidant status (TOS), IL-6, TNF alpha levels in groups C and TD/Col were significantly lower than groups TD and TD/M (P<.001).

CONCLUSION

Our study results revealed that colchicine reduced testicular ischemia-reperfusion injury in experimental rat testis torsion model. Although detorsion of testis is crucial for the preserving the testicular viability, antioxidant and anti-inflammatory treatment modalities like colchicine might help to reduce ischemia-reperfusion injury in detorsed testis.

Protective role of garlic oil against oxidative damage induced by furan exposure from weaning through adulthood in adult rat testis

Furan is produced in a wide variety of heat-treated foods via thermal degradation. Furan contamination is found to be relatively high in processed baby foods, cereal products, fruits juices, and canned vegetables. Several studies have demonstrated that furan is a potent hepatotoxin and hepatocarcinogen in rodents. However, few studies have investigated the toxic effects of furan in the testis. In addition, the exact mechanism(s) by which furan exerts toxicity in the testis has not been fully elucidated. In this study, we investigated the potential of furan exposure from weaning through adulthood to induce oxidative stress in adult rat testis, as well as the potential of garlic oil (GO) to ameliorate the induced toxicity. Our results reveal that furan administration significantly reduced serum testosterone levels and increased the levels of malondialdehyde (MDA); furthermore, furan administration decreased significantly the enzymatic activity of testicular antioxidants, including glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) and induced histopathological alterations in the testis. GO co-administration ameliorated the reduction in testosterone levels and dramatically attenuated the furan-induced oxidative and histopathological changes. In addition, Go significantly down-regulated the increased caspase-3 and cytochrome P450 2E1 (CYP2E1) expression in the furan-treated testis. To the best of our knowledge, this study is the first to demonstrate the furan-induced oxidative changes in the adult rat testis and the protective role of GO to ameliorate these changes through its antioxidant effects and its ability to inhibit CYP2E1 production.