Abstract
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-κβ), tumour necrotic factor α (Tnf-α) and interleukin 1β (Il-1β) 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.