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The purpose of this study was to assess the effects of dietary fish oil (FO) and rooibos supplementation on semen quality, fatty acids composition and reproductive performance of aged male broiler breeders. Seventy-two 47-week-old Ross broiler breeder roosters were randomly assigned to a 2 × 3 factorial arrangements to include two FO concentrations (0% and 2%) and 3 rooibos concentrations (0%, 1.5% and 3%) for 13 weeks consecutive. The different diets affected semen parameters significantly (p 0.05), except for the semen concentration and abnormality of the sperm. The sperm of the FO and 3% rooibos-treated group showed better motility and viability when compared to the other groups (p 0.05). The susceptibility of semen to lipid peroxidation was increased in roosters fed the rooibos-free diets (p 0.05), but it was reduced (p 0.05) when the diet was supplemented with 1.5% and 3% rooibos. In addition, at 64 weeks, the highest concentration of testosterone was observed in the roosters fed a diet that included 2% FO and 3% rooibos (p 0.05); however, the difference in testosterone levels between Week 52 and Week 64 was not significant (p 0.05). The fertility rate of collected eggs from the FO and 3% rooibos group was higher (p 0.05) than that of the other groups at the end of the experiment. In conclusion, dietary inclusion of FO along with rooibos improved seminal quality and reproduction performance in aged roosters.

Fumonisins are a family of potentially carcinogenic mycotoxins produced by Fusarium verticillioides. Several fumonisins have been identified with fumonisin B1 (FB1 ) being the most toxic. The canonical mechanism of FB1 toxicity is centered on its structural resemblance with sphinganine and consequent competitive inhibition of ceramide synthase and disruption of lipidomic profiles. Recent and emerging evidence at the molecular level has identified the disruption of mitochondria and excessive generation of toxic reactive oxygen species (ROS) as alternative/additional mechanisms of toxicity. The understanding of how these pathways contribute to FB1 toxicity can lead to the identification of novel, effective approaches to protecting vulnerable populations. Natural compounds with antioxidant properties seem to protect against the induced toxic effects of FB1 . Rooibos (Aspalathus linearis), endemic to South Africa, has traditionally been used as a medicinal herbal tea with strong scientific evidence supporting its anecdotal claims. The unique composition of phytochemicals and combination of metabolic activators, adaptogens and antioxidants make rooibos an attractive yet underappreciated intervention for FB1 toxicoses. In the search for a means to address FB1 toxicoses as a food safety problem in developing countries, phytomedicine and traditional knowledge systems must play an integral part. This review aims to summarize the growing body of evidence succinctly, which highlights mitochondrial dysfunction as a secondary toxic effect responsible for the FB1 -induced generation of ROS. We further propose the potential of rooibos to combat this induced toxicity based on its integrated bioactive properties, as a socio-economically viable strategy to prevent and/or repair cellular damage caused by FB1 .

cope To determine the effect of Rooibos (Aspalathus linearis) on glucocorticoid biosynthesis and inactivation in vivo and in vitro. Methods and results Ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) analyses of in vivo studies showed that human Rooibos consumption increased cortisone plasma levels in males (p = 0.0465) and reduced cortisol:cortisone ratios in males and females (p = 0.0486) at risk for cardiovascular disease. In rats, corticosterone (CORT) (p = 0.0275) and deoxycorticosterone (p = 0.0298) levels as well as the CORT:testosterone ratio (p = 0.0009) decreased following Rooibos consumption. The inactivation of cortisol was investigated in vitro by expressing 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1) and type 2 (11βHSD2) in CHO-K1 cells. Rooibos inhibited 11βHSD1, which resulted in a significant reduction in the cortisol:cortisone ratio (p < 0.01). No significant effect was detected on 11βHSD2. In vitro studies in adrenal H295R cells showed that Rooibos and rutin, one of the more stable flavonoid compounds present in Rooibos, significantly reduced the levels of cortisol and CORT in cells stimulated with forskolin to mimic a stress response. Conclusion In vivo studies demonstrate that Rooibos significantly decreased glucocorticoid levels in rats and steroid metabolite ratios linked to metabolic disorders—cortisol:cortisone in humans and CORT:testosterone in rats. Results obtained at cellular level elucidate possible mechanisms by which these effects were achieved.

Reactive oxygen species (ROS) are involved in many physiological functions of mammalian sperm. Numerous endogenous antioxidants belonging to both enzymatic and non-enzymatic groups can remove excess ROS and prevent oxidative stress (OS). This study compares the modulation of OS by rooibos, Chinese green tea and commercial rooibos and green tea supplements in rat sperm. Male Wistar rats (n = 60) were supplemented with fermented rooibos, ‘green’ rooibos, Chinese green tea, rooibos supplement, green tea supplement or water for 10 weeks while OS was induced during the last 2 weeks. Sperm count and motility were significantly higher for rats consuming fermented rooibos and ‘green’ rooibos when compared with the other groups. Catalase activity was significantly higher in the sperm of rats consuming fermented rooibos, ‘green’ rooibos and both the rooibos and green tea supplements. Superoxide dismutase concentration in the sperm of rats supplemented with fermented rooibos, ‘green’ rooibos and green tea was higher. Sperm glutathione levels of rats consuming the fermented and ‘green’ rooibos were also significantly higher. Rooibos fermented and ‘green’ rooibos showed a tendency to lower the levels of ROS and lipid peroxidation when compared with the control group. In conclusion, both rooibos extracts could offer a measure of protection against induced oxidative damage by increasing the antioxidant defence mechanisms and thereby improving the sperm quality and function. Copyright © 2012 John Wiley & Sons, Ltd.

The antioxidant properties of the fruit of the Rosa roxburghii (RR) plant have been associated with several putative health promoting effects. The possible cytotoxic, mutagenic/antimutagenic and genotoxic effects of RR fruit extract were investigated. The effect on antioxidant status and protection against induced oxidative stress were also investigated using primary rat hepatocytes. A RR fruit extract containing 45 g/L total ascorbic acid and 65 g/L total polyphenols was used in this study. Dilutions up to 0.08% (v/v) increased significantly the antioxidant status in primary rat hepatocytes. The glutathione redox state was decreased with RR treatment but was increased in Chang liver cells and MT-2 lymphoblast. No cyto- or genotoxicity were observed at levels of up to 5% (v/v) of the fruit extract. In addition, a significant protection against t-BHP induced oxidative stress was observed in primary rat hepatocytes. The Ames test revealed no mutagenic activity using the Salmonella typhimurium strains TA98, TA100 and TA102. A significant antimutagenic effect of the extract was observed against the metabolic activated mutagens 2-acetylaminofluorene and aflatoxin B1 and to a lesser extent against methyl methanesulfonate. It is concluded that these results support the associated health promoting potential of Rosa Roxburghii fruit and in particular against oxidative stress. Copyright © 2007 John Wiley & Sons, Ltd.