The methanolic extract of Hibiscus sabdariffa downregulates the relative expression of Kiss1 gene in the hypothalamus of Wistar rats: A preliminary report.

Objective: Kiss1 gene expression in the rat hypothalamus was investigated following administration of methanolic extract of Hibiscus sabdariffa (MEHS) to provide mechanistic evidence for the reproductive effect of the MEHS as a potential regulator of Kiss1 gene (which directly controls the hypogonadal axis). Materials and Methods: This experiment was done using fifteen (15) male rats with average weight of 148 g, randomly grouped into three (3) groups (A-C). Group A was the control group and received no treatment. Group B and C were orally administered with 200 mg/kg and 400 mg/kg of MEHS, respectively. The animals received the extract once a day for twenty-one (21) days. The hypothalamus was harvested on the last day of administration to investigate antioxidant levels, histopathology, and Kiss1 gene expression. Results: The relative expression of Kiss1 gene in the group C was downregulated compared to the control group (p=0.023). No significant changes were seen in the antioxidant levels of the groups treated with MEHS when compared to the control. MEHS had no histopathological effects in the hypothalamus at both low (200 mg/kg) and high (400 mg/kg) doses. Conclusion: High-dose MEHS lowers the expression of the Kiss1 gene in the hypothalamus. However, this effect could not be explained by the oxidative profile or histology of the hypothalamus.

Kiss1 gene expression, sperm indices and testicular histopathology following the administration of Hibiscus sabdariffa in rats.

OBJECTIVE: This study investigated the expression of Kiss1 gene on the testis and the blood of Wistar rats, following the administration of methanolic extract of Hibiscus Sabdariffa (MEHS). METHODS: Fifteen (15) rats with an average weight of 204g were randomly divided into three (3) groups (A-C). Group A was given no treatment and served as the normal control group. Groups B and C were orally administered 200mg/kg and 400mg/kg of MEHS, respectively. The extract was administered once a day for 21 days. RESULTS: There was a significant increase in the relative testicular weight in group B and C compared to the control group (p=0.035). There was no significant difference in the sperm parameters, reproductive hormones, and antioxidant levels in all the treatment groups when compared to the control group (p>0.05). There is a significantly lower expression intensity of the Kiss1 gene in the blood in groups B (p=0.000) and C (p=0.017), compared to the control group. There is no difference in the relative intensity of Kiss1 gene expression in the testis of all the experimental groups (p=0.173). CONCLUSIONS: MEHS caused no histopathological changes on the testis at both doses. MEHS shows the potential of downregulating the expression of the Kiss1 gene in the blood. However, this effect lacks a regulatory mechanism on the reproductive hormones, sperm parameters, testicular morphology, and antioxidative levels.

The Reproductive Functions of the Human Brain Regions: A Systematic Review.

Reproduction remains a vital characteristic of living things necessary for survival and continuity. Specific brain regions and structures are responsible for regulating the different aspects of human reproduction. This study systematically reviewed the brain regions that play structural, hormonal and physiological roles in controlling the various aspects of human reproduction from puberty, sexual function, gametogenesis, childbirth and fertility to infertility to inform advancement in research and therapeutic interventions in human reproductive disorders. A systematic literature search of online databases (MEDLINE, Europe PMC and Google Scholar) was made using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for observational and cross-sectional studies providing evidence for the role(s) of the brain region in human reproduction from the year 2011-2021. Out of 141 articles found, 15 studies met the inclusion criteria, including six cross-sectional and nine randomised controlled trials. The study acknowledged the roles of the pituitary gland, hypothalamus and pineal gland, widely known for regulating the human reproductive system in a gender-based approach while highlighting essential gaps and opportunities for future research. This review provides a 10-year update and overview of the role of different brain regions in human reproduction and will stimulate future research in human reproduction.