Therapeutic Effects of Bee Bread on Obesity-Induced Testicular-Derived Oxidative Stress, Inflammation, and Apoptosis in High-Fat Diet Obese Rat Model.

Obesity is a debilitating disorder with a variety of problems including oxidative stress, inflammation, and apoptosis. The aim of our study was to investigate the therapeutic role of bee bread on oxidative stress, apoptosis, and inflammation in the testis of obese rats. Thirty-two adult male Sprague Dawley rats, with weights between 230-300 g, were distributed into four groups (n = 8/group), namely normal control (C), obese (Ob), obese + BB or obese + OR [high-fat diet (HFD) for 6 weeks then HFD plus bee bread or orlistat for another 6 weeks] groups. Bee bread (0.5 g/kg) or orlistat (10 mg/kg/day) was diluted with distilled water and administered daily for 6 weeks by oral gavage. There were significant decreases in the activities of antioxidant enzymes [glutathione-S-transferase (GST), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione reductase (GR)], glutathione (GSH)] and total antioxidant capacity (TAC) levels and mRNA expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), superoxide dismutase (Sod), catalase (Cat) and glutathione peroxidase (Gpx) in the obese group relative to the control group. Meanwhile, the mRNA levels of pro-inflammatory markers, namely: inducible nitric oxide synthase (Inos), nuclear factor kappa B (Nf-κß), tumour necrotic factor α (Tnf-α) and interleukin 1ß (Il-1ß) were significantly increased while interleukin (Il-10) was decreased in the obese group relative to the control group. Further, proliferating cell nuclear antigen (PCNA) immunoexpressions decreased while cleaved caspase-3 immunohistochemical staining increased significantly in the obese group, in addition to increases in the mRNA levels of p53, Bax, Caspases-8, 9 and 3, relative to the control group. Treatment with bee bread showed increases in antioxidant enzymes and PCNA immunoexpression, as well as decreases in inflammation and apoptosis markers in the testes. This study has shown that bee bread has therapeutic effects against oxidative stress, inflammation, apoptosis in the testis of HFD-induced obese male rats, thereby suggesting its role as a natural supplement capable of treating obesity-induced male reproductive impairment.

Chemical Profile, Antioxidant Properties and Antimicrobial Activities of Malaysian Heterotrigona itama Bee Bread.

The aim of the study was to determine the chemical profile, antioxidant properties and antimicrobial activities of Heterotrigona itama bee bread from Malaysia. The pH, presence of phytochemicals, antioxidant properties, total phenolic content (TPC) and total flavonoid content (TFC), as well as antimicrobial activities, were assessed. Results revealed a decrease in the pH of bee bread water extract (BBW) relative to bee bread ethanolic extract (BBE) and bee bread hot water extract (BBH). Further, alkaloids, flavonoids, phenols, tannins, saponins, terpenoids, resins, glycosides and xanthoproteins were detected in BBW, BBH and BBE. Also, significant decreases in TPC, TFC, DPPH activity and FRAP were detected in BBW relative to BBH and BBE. We detected phenolic acids such as gallic acid, caffeic acid, trans-ferulic acid, trans 3-hydroxycinnamic acid and 2-hydroxycinnamic acid, and flavonoids such as quercetin, kaempferol, apigenin and mangiferin in BBE using high-performance liquid chromatography analysis. The strongest antimicrobial activity was observed in Klebsilla pneumonia (MIC50 1.914 µg/mL), followed by E. coli (MIC50 1.923 µg/mL), Shigella (MIC50 1.813 µg/mL) and Salmonella typhi (MIC50 1.617 µg/mL). Bee bread samples possess antioxidant and antimicrobial properties. Bee bread contains phenolic acids and flavonoids, and could be beneficial in the management and treatment of metabolic diseases.

Malaysian Propolis and Metformin Synergistically Mitigate Kidney Oxidative Stress and Inflammation in Streptozotocin-Induced Diabetic Rats.

Diabetic nephropathy is reported to occur as a result of the interactions between several pathophysiological disturbances, as well as renal oxidative stress and inflammation. We examined the effect of Malaysian propolis (MP), which has anti-hyperglycemic, antioxidant and anti-inflammatory properties, on diabetes-induced nephropathy. Diabetic rats were either treated with distilled water (diabetic control (DC) group), MP (300 mg/kg b.w./day), metformin (300 mg/kg b.w./day) or MP + metformin for four weeks. We found significant increases in serum creatinine, urea and uric acid levels, decreases in serum sodium and chloride levels, and increase in kidney lactate dehydrogenase activity in DC group. Furthermore, malondialdehyde level increased significantly, while kidney antioxidant enzymes activities, glutathione level and total antioxidant capacity decreased significantly in DC group. Similarly, kidney immunoexpression of nuclear factor kappa B, tumor necrosis factor-α, interleukin (IL)-1ß and caspase-3 increased significantly, while IL-10 immunoexpression decreased significantly in DC group relative to normal control group. Histopathological observations for DC group corroborated the biochemical data. Intervention with MP, metformin or both significantly mitigated these effects and improved renal function, with the best outcome following the combined therapy. MP attenuates diabetic nephropathy and exhibits combined beneficial effect with metformin.

Bee bread mitigates downregulation of steroidogenic genes, decreased spermatogenesis, and epididymal oxidative stress in male rats fed with high-fat diet.

The pituitary-gonadal axis plays an important role in steroidogenesis and spermatogenesis, and by extension, fertility. The aim of this study was to investigate the protective role of bee bread, a natural bee product, against obesity-induced decreases in steroidogenesis and spermatogenesis. Thirty-two adult male Sprague-Dawley rats weighing between 200 and 300 g were divided into four groups (n = 8/group), namely: normal control (NC), high-fat diet (HFD), HFD plus bee bread administered concurrently for 12 wk (HFD + B), HFD plus orlistat administered concurrently for 12 wk (HFD + O) groups. Bee bread (0.5 g/kg) or orlistat (10 mg/kg/day) was suspended in distilled water and given by oral gavage daily for 12 wk. Levels of follicle-stimulating hormone, luteinizing hormone, testosterone, and adiponectin, as well as sperm count, motility, viability, normal morphology, and epididymal antioxidants decreased, whereas levels of leptin, malondialdehyde, and sperm nDNA fragmentation increased significantly in the HFD group relative to the NC group. There were significant decreases in the testicular mRNA transcript levels of androgen receptor, luteinizing hormone receptor, steroidogenic acute regulatory protein, cytochrome P450 enzyme, 3ß-hydroxysteroid dehydrogenase (HSD) and 17ß-HSD in the testes of the HFD group. Furthermore, mount, intromission and ejaculatory latencies increased, and penile cGMP level decreased significantly in the HFD group. Supplementation with bee bread significantly reduced leptin level and increased adiponectin level, enhanced sperm parameters and reduced sperm nDNA fragmentation, upregulated the levels of steroidogenic genes and proteins in HFD-induced obese male rats. Bee bread improved steroidogenesis and spermatogenesis by upregulating steroidogenic genes. Therefore, bee bread may be considered as a potential supplementation to protect against infertility in overweight men or men with obesity.NEW & NOTEWORTHY The high-fat diet utilized in the present study induced obesity in the male rats. Bee bread supplementation mitigated impaired steroidogenesis, spermatogenesis, mating behavior, and fertility potential by counteracting the downregulation of steroidogenic genes, thus increasing testosterone levels and suppressing epididymal oxidative stress. These benefits may be due to the abundance of phenolic and flavonoid compounds in bee bread.

Metformin mitigates impaired testicular lactate transport/utilisation and improves sexual behaviour in streptozotocin-induced diabetic rats.

CONTEXT: Lactate is the preferred energy substrate for developing testicular germ cells. Diabetes is associated with impaired testicular lactate transport/utilisation, and poor sexual behaviour. OBJECTIVE: To examine the effects of metformin on parameters involved in testicular lactate production, transport/utilisation, and sexual behaviour in diabetic state. METHODS: Male Sprague-Dawley rats were assigned into normal control (NC), diabetic control (DC), and metformin-treated diabetic group (n = 6/group). Metformin (300 mg/kg b.w./day) was administrated orally for 4 weeks. RESULTS: Intra-testicular glucose and lactate levels, and lactate dehydrogenase (LDH) activity increased, while the mRNA transcript levels of genes responsible for testicular glucose and lactate transport/utilisation (glucose transporter 3, monocarboxylate transporter 4 (MCT4), MCT2, and LDH type C) decreased in DC group. Furthermore, penile nitric oxide increased, while cyclic guanosine monophosphate decreased, with impaired sexual behaviour in DC group. Treatment with metformin improved these parameters. CONCLUSIONS: Metformin increases testicular lactate transport/utilisation and improves sexual behaviour in diabetic state.

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.

Composition of Royal Jelly (RJ) and Its Anti-Androgenic Effect on Reproductive Parameters in a Polycystic Ovarian Syndrome (PCOS) Animal Model.

Royal jelly (RJ) has been shown to contribute its positive effects upon imbalance in the reproductive system. However, it remains unknown as to whether RJ has an anti-androgenic effect on reproductive parameters in a polycystic ovarian syndrome (PCOS) animal model. Composition of RJ was assessed by phytochemical screening and the LC-MS method. Forty immature female rats (3 weeks, 40-50 g) were randomly divided into five groups (n = 8 per group), i.e., control, testosterone (T), T+100RJ (100 mg/kg/day), T+200RJ (200 mg/kg/day RJ), and T+400RJ (400 mg/kg/day RJ) groups. Hyperandrogenism was induced by daily subcutaneous injection of T propionate for 3 weeks, followed by oral RJ for 4 weeks. The T+200RJ group had a significantly higher follicle-stimulating hormone level, and significantly lower luteinizing hormone, testosterone, and estradiol levels in comparison to the T group. Malondialdehyde level and glutathione peroxidase activity were significantly lower, while total antioxidant capacity level was significantly higher in the T+200RJ group compared to the T group. Histologically, the T+200RJ group showed recovery of various stages of ovarian follicular development. RJ at 200 mg/kg/day for 4 weeks significantly improved reproductive parameters in PCOS rats partly due to its anti-androgenic effect through antioxidant action and probably due to modulation on estrogenic activity, which needs further study to evaluate its exact mechanism of action.

Oxidative Stress, NF-κB-Mediated Inflammation and Apoptosis in the Testes of Streptozotocin-Induced Diabetic Rats: Combined Protective Effects of Malaysian Propolis and Metformin.

Oxidative stress, inflammation and apoptosis are major complications that trigger organ failure in diabetes mellitus (DM), and are proven to adversely affect the male reproductive system. Clinical and experimental studies have demonstrated the promising protective effects of propolis in DM and its associated systemic effects. Herein, we investigated the effect of Malaysian propolis (MP) on testicular oxidative stress, inflammation and apoptosis in diabetic rats. Further, the possibility of a complementary effect of MP with the anti-hyperglycaemic agent, metformin (Met), was studied with the idea of recommending its use in the event that Met alone is unable to contain the negative effects of DM on the male reproductive system in mind. Male Sprague-Dawley rats were either gavaged distilled water (normoglycaemic control and diabetic control groups), MP (diabetic rats on MP), Met (diabetic rats on Met) or MP+Met (diabetic rats on MP+Met), for 4 weeks. MP decreased oxidative stress by up-regulating (p < 0.05) testicular mRNA levels of nuclear factor erythroid 2-related factor 2, superoxide dismutase, catalase and glutathione peroxidase; increasing (p < 0.05) the activities of antioxidant enzymes; and decreasing (p < 0.05) lipid peroxidation in the testes and epididymis of diabetic rats. Further, MP down-regulated (p < 0.05) testicular mRNA and protein levels of pro-inflammatory mediators (nuclear factor kappa B, inducible nitric oxide synthase, tumour necrosis factor-α and interleukin (IL)-1ß), decreased (p < 0.05) the nitric oxide level, and increased (p < 0.05) IL-10 mRNA and protein levels. MP also down-regulated (p < 0.05) Bax/Bcl-2, p53, casapase-8, caspase-9 and caspase-3 genes, and increased (p < 0.05) testicular germ cell proliferation. MP's effects were comparable to Met. However, the best results were achieved following co-administration of MP and Met. Therefore, we concluded that administration of the MP+Met combination better attenuates testicular oxidative stress, inflammation and apoptosis in DM, relative to MP or Met monotherapy, and may improve the fertility of males with DM.

Antioxidant, anti-inflammatory and synergistic anti-hyperglycemic effects of Malaysian propolis and metformin in streptozotocin-induced diabetic rats.

Diabetes mellitus is characterized by hyperglycemia which causes oxidative stress. Propolis has been reported to have antihyperglycemic and antioxidant potentials. The present study therefore examined the anti-hyperglycemic, antioxidant and anti-inflammatory activities of Malaysian propolis (MP) using streptozotocin-induced diabetic rats. Ethanol extract of MP showed in vitro antioxidant (DPPH, FRAP and H2O2 radical scavenging) and α-glucosidase inhibition activities. Male Sprague Dawley rats were either treated with distilled water (normal control and diabetic control), MP (300 mg/kg b. w.), metformin (Met) (300 mg/kg b. w.) or both. After four weeks, fasting blood glucose decreased, while body weight change and serum insulin level increased significantly in MP, Met and MP + Met treated diabetic groups compared to diabetic control (DC) group. Furthermore, pancreatic antioxidant enzymes, total antioxidant capacity, interleukin (IL)-10 and proliferating cell nuclear antigen increased, while malondialdehyde, nuclear factor-kappa B (p65), tumor necrosis factor alpha, IL-1ß and cleaved caspase-3 decreased significantly in the treated diabetic groups compared to DC group. Histopathology of the pancreas showed increased islet area and number of beta cells in the treated groups, compared to DC group, with D + MP + Met group comparable to normal control. We conclude that MP has anti-hyperglycemic, antioxidant, anti-inflammatory and antiapoptotic potentials, and exhibits synergistic effect with metformin.