Effets of trihoney on reproductive dysfunctions in high cholesterol diet-fed male rabbits

Abstract

Overconsumption of high-cholesterol diet induces hypercholesterolemia and disturbs cholesterol homeostasis in the body which adversely affects normal male reproductive functions. Use of honey has become of increasing interest due to the increase in the availability of evidence-based findings demonstrating the beneficial effects of honey in treating diverse diseases. The present study was undertaken to evaluate the potential protective effects of Trihoney (a mixture of Trigona, Mellifera and Tualang) against male reproductive dysfunctions in diet-induced hypercholesterolemic rabbits and compare its effects with atorvastatin. Forty-eight male New Zealand white rabbits at the age of 5 months were assigned into 6 groups. Two groups were fed commercial rabbit pellet and 0 and 0.6 g/kg/day of Trihoney respectively. The other four groups were fed 1% cholesterol diet and 0, 0.3, 0.6 g/kg/day of Trihoney, and 2 mg/kg/day of atorvastatin for 12 weeks. The study was planned in 5 distinct phases. The purpose of the first phase was to evaluate the effects of Trihoney on serum lipid profile and serum and testicular malondialdehyde (MDA) and antioxidant enzymes; superoxide dismutase (SOD) and glutathione peroxidase (GPx). Trihoney and atorvastatin reduced serum total cholesterol and LDL-c significantly. Trihoney was as effective as atorvastatin in the lipid lowering effect. Trihoney slightly reduced serum MDA but significantly enhanced serum SOD and GPx. It reduced testicular MDA and increased SOD significantly. Atorvastatin treatment significantly reduced serum and testicular MDA and enhanced serum and testicular SOD and GPx. In the second phase, the effect of Trihoney on serum inflammatory biomarkers was evaluated. Trihoney administration reduced serum levels of IL-6, TNF-α and IL-1β significantly. Atorvastatin reduced serum TNF-α and IL-1β significantly. In the third phase, the effects of Trihoney on serum and intra-testicular testosterone, serum FSH, serum LH, fasting insulin, fasting blood glucose and HOMA-IR were investigated. Trihoney particularly at the dose of 0.6 g/kg/day significantly improved serum and intra-testicular testosterone and serum FSH; whereas, atorvastatin showed no improvement in these hormones. Both Trihoney and atorvastatin showed no effects on fasting serum insulin, fasting blood glucose and HOMA-IR. The fourth phase was aimed to evaluate the effects of Trihoney on sperm parameters. Trihoney particularly at the dose of 0.6 g/kg/day improved the percentages of sperm motility and sperm with normal morphology as well as reduced the percentages of immotile sperm and sperm with abnormal morphology. Trihoney improved sperm concentration but with no statistical significant. Atorvastatin group showed the worst outcome of sperm parameters. In the fifth phase, the effects of Trihoney on testicular and epididymal histopathological changes were evaluated. Trihoney ameliorated the testicular degenerative changes, improved spermatogenesis and maintained the normal histology of the epididymis with an increase in the number of sperm in its tubules. Atorvastatin treated group showed severe testicular tubular degenerative changes and epididymal atrophy with fibrosis. In conclusion, Trihoney showed its potential health benefits as an effective hypocholesterolemic, anti-inflammatory and antioxidant agent. It was shown to improve sperm parameters and male reproductive hormones, and attenuate testicular and epididymal histopathological alterations in high-cholesterol diet fed male rabbits. Hence, Trihoney plays a favourable role on several mechanisms involved in combating hypercholesterolemia-induced male reproductive dysfunctions