Protective effects of bee bread on testicular oxidative stress, NF-κB-mediated inflammation, apoptosis and lactate transport decline in obese male rats.

Oxidative stress, chronic inflammation and apoptosis are associated with obesity. Herein, we investigated the potential protective effect of bee bread, a natural bee product, on testicular oxidative stress, inflammation and apoptosis, as well as lactate transport in the testis of high-fat diet (HFD)-induced obese rats. Adult male Sprague-Dawley rats were either fed with normal chow (NC), HFD, HFD + bee bread (0.5 g/kg b.w./day) or HFD + orlistat (10 mg/kg b.w./day) for 12 weeks. Our results show significant decreases in the activities and mRNA expression of antioxidant genes (Nrf2, Sod, Cat and Gpx), with significant increase in pro-inflammatory (Nf-κb, Tnf-α, iNos, Il-1ß) and pro-apoptotic (p53, Bax, Bax/Bcl2, Caspase-8, Caspase-9 and Caspase-3) genes in the testis of HFD group relative to the NC group. Furthermore, proliferating cell nuclear antigen (PCNA) was poorly expressed in the testis of the HFD group relative to the NC group. Similarly, the mRNA levels of glucose transporters (Glut1 and Glut3), monocarboxylate transporters (Mct2 and Mct4) and lactate dehydrogenase type C (Ldhc) decreased significantly, with decrease in lactate utilisation. Treatment with bee bread upregulated testicular antioxidant enzymes, downregulated inflammation and apoptosis, and increased PCNA immunoexpression, in addition to improving lactate transport. Taken together, our results suggest that bee bread is a promising natural product with the potential to improve male fertility.

Orlistat reverses intratesticular lactate transport decline and infertility in male obese rats.

Obesity and its accompanying complications predispose to abnormal testicular glucose metabolism, penile erectile dysfunction and subfertility. This study examined the potentials of orlistat in attenuating erectile dysfunction and fertility decline in high-fat diet (HFD)-induced obesity in male rats. Eighteen adult male Sprague-Dawley rats whose weights were between 250 and 300 g were divided into three groups (n = 6/group) namely: normal control (NC), HFD and HFD + orlistat (10 mg/kg body weight/day co-administered for 12 weeks) (HFD+O). During the 11th and 12th week, mating behaviour and fertility parameters were evaluated, and parameters of glucose metabolism were assessed at the end of the 12th week. Orlistat increased testicular mRNA levels of glucose transporters (Glut1 and Glut3), monocarboxylate transporters (Mct2 and Mct4) and lactate dehydrogenase type C (Ldhc), decreased intratesticular lactate and glucose levels, and LDH activity in obese rats. Furthermore, orlistat increased superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and glutathione reductase (GR) activities, and total antioxidant capacity (TAC), but decreased malondialdehyde level in the penis of obese rats. Similarly, orlistat improved penile cGMP level, sexual behaviour and fertility outcome in obese rats. Penile cGMP level correlated positively with total mounts and intromissions but correlated negatively with mount/intromission ratio. Orlistat improves fertility potential in obese state by targeting testicular lactate metabolism, penile oxidative stress and sexual behaviour in rats. Therefore, orlistat shows a promising protective effect and may preserve the fertility potential of obese men.

The methanolic extract of Guibourtia tessmannii (caesalpiniaceae) and selenium modulate cytosolic calcium accumulation, apoptosis and oxidative stress in R2C tumour Leydig cells: Involvement of TRPV1 channels.

This study evaluated the effects of the methanolic extract of Guibourtia tessmannii (GT) and selenium (Se) on cell viability, intracellular calcium concentration ([Ca2+ ]i ), apoptosis and oxidative stress through transient receptor potential vanilloid 1 (TRPV1) channel activity in CCL-97 (R2C) tumour Leydig cells. The cells were divided into nine groups and treated as follows: (a)-Control, (b)-Capsazepine (CPZ, 0.1 mM, a TRPV1 channel blocker), (c)-Capsaicin (CAP, 0.01 mM, a TRPV1 channel activator), (d)-GT (500 µg/ml), (e)-GT+CPZ, (f)-GT+CAP, (g)-Se (200 nM), (h)-Se+CPZ and (i)-Se+CAP. After treatments, cell viability, [Ca2+ ]i , apoptosis, caspase 3/9, reactive oxygen species (ROS) and mitochondrial membrane depolarisation (MMD) were evaluated. The [Ca2+ ]i , apoptosis, caspase 3/9, MMD and ROS levels were significantly (p < 0.001) increased in CAP group, but lowered in CPZ group. Interestingly, these parameters were significantly (p < 0.001) improved by GT and Se, compared to the CAP group. Moreover, the co-administration of GT+CAP or Se+CAP inhibited the cytotoxicity of CAP. Thus, the modulatory properties of GT and Se on Ca2+ influx, apoptosis and oxidative stress require the integrity of TRPV1 channel in CCL-97 Leydig cells. These results suggest that GT and Se might be used in the management of cytotoxicity in the testes, involving TRPV1 channel activity.

Propolis improves pregnancy outcomes and placental oxidative stress status in streptozotocin-induced diabetic rats.

BACKGROUND: This study assessed the effects of propolis alone or combined with insulin on maternal status, pregnancy outcomes and placental oxidative stress in streptozotocin-induced diabetic rats. METHODS: Forty female rats were randomly assigned into five groups (n = 8/group) i.e. non-DM (non-diabetes), DM (diabetes), DM + Propolis (diabetes on propolis orally); DM + Insulin (diabetes on insulin subcutaneously) and DM + Combined (diabetes on propolis and insulin) groups. Propolis and insulin were given at 300 mg/kg/day orally and 5.0 IU/kg/day subcutaneously, respectively, for 4 weeks. RESULTS: Fasting blood glucose, conception period, implantation losses, foetal blood glucose and placental oxidative stress markers such as malonaldehyde and protein carbonyl were significantly higher while maternal weight gain, foetal body weight and total antioxidant capacity were significantly lower in DM group compared with non-DM group. These changes were significantly improved in rats treated with propolis or insulin alone with greater significant effects in rats treated with both propolis and insulin. CONCLUSION: This study may suggest the protective effects of propolis against DM-induced impaired pregnancy outcomes and placental oxidative stress with greater effects when combined with insulin.

Quercetin exerts preventive, ameliorative and prophylactic effects on cadmium chloride - induced oxidative stress in the uterus and ovaries of female Wistar rats.

This study examined the possible protective effect of quercetin(QE) on cadmium chloride (CdCl2) - induced reproductive toxicity in female rats. Cadmium (Cd) accumulated in the uterus and ovaries of rats, decreased antioxidants [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione (GSH)], and raised the concentrations of malondialdehyde (MDA) and hydrogen peroxide (H2O2) in the uterus and ovaries of rats. Serum concentrations of estradiol, progesterone, follicle stimulating hormone and luteinizing hormone decreased significantly after CdCl2 administration. Caspase-3 activity significantly increased in the ovaries, with an increase in Bax and a decrease in Bcl-2 protein expressions after CdCl2 treatment. Histopathology of the ovaries revealed significant decrease in follicle number, while the uterus showed cyst-like endometrial glands. All three models of QE treatment [pre-treatment (QE + CdCl2), post-treatment (CdCl2+QE), simultaneous treatment (CdCl2/QE)] decreased Cd accumulation, MDA, H2O2, and increased SOD, CAT and GPx activities in the uterus and ovaries, decreased apoptosis of follicular cells, and increased serum reproductive hormones. However, the QE pre-treated model offered better protection against CdCl2 relative to the other two models. These results suggest that, QE exerts multi-mechanistic protective effects against cadmium toxicity attributable to its antioxidant and anti-apoptotic actions.