Bulbine natalensis Stem Extract Enhances Sexual Function in Male Rats
A study published in the International Journal of Andrology has found that an aqueous extract from the stem of the Bulbine natalensis plant exhibits aphrodisiac and pro-erectile properties when administered to male rats.
Bulbine natalensis, also known as rooiwortel or ibhucu, is a plant species native to South Africa that has been used in traditional medicine for treating various ailments including venereal diseases. Researchers from the University of Fort Hare investigated the effects of the plant’s stem extract on male rat sexual behavior.
Phytochemical screening revealed the extract contained compounds like saponins, cardiac glycosides, tannins, alkaloids and anthraquinones. When given at doses of 25 and 50 mg/kg body weight, the extract significantly improved sexual performance parameters in the rats such as:
– Increased mount frequency, intromission frequency, ejaculation frequency and ejaculatory latency
– Reduced mount latency, intromission latency and post-ejaculatory interval
– Enhanced penile reflexes like erections, flips and total penile reflexes
– Elevated serum testosterone and luteinizing hormone levels
The aphrodisiac activity was more pronounced at the 50 mg/kg dose. The extract likely boosted sexual function by increasing androgens and facilitating the hypothalamic-pituitary-gonadal axis. The presence of saponins may have contributed to raising endogenous testosterone production.
In contrast, the highest 100 mg/kg dose exhibited contrasting effects, impairing sexual behaviors potentially due to sedative effects at that higher amount.
The researchers conclude that Bulbine natalensis stem extract, particularly at 25-50 mg/kg doses, shows promise as a natural therapeutic for treating male sexual disorders like low libido, premature ejaculation and erectile dysfunction. Its pro-sexual effects validate the traditional use of this plant for enhancing male sexual vigor.
Further research is still needed, including clinical studies in humans, but this study provides evidence for the aphrodisiac properties of Bulbine natalensis derived from its phytochemical constituents like saponins and alkaloids. Developing treatments from this plant could offer a natural alternative for managing male sexual dysfunctions
Conclusion:
Rat studies provide important preclinical data for evaluating potential effects in humans, but there are some key limitations in directly translating the findings to human use:
1. Species differences – Rats and humans are different species with physiological and biochemical differences that can affect how a compound is absorbed, metabolized, and exerts its effects.
2. Dosing – The effective doses used in rat studies (25-50 mg/kg body weight in this case) need to be carefully extrapolated and tested to determine safe and effective human-equivalent doses.
3. Route of administration – This study used oral administration in rats, which may differ from other routes like topical application if developed for human use.
4. Metabolism – Rats and humans can metabolize compounds differently, altering the therapeutic effects and toxicity profiles.
5. Sexual behavior models – The sexual behavior paradigms used to test rats do not fully represent the complexity of human sexual function and response.
To translate rat study findings like these to human applications, some key steps are typically followed:
1) In vitro studies – Testing the extract/compounds on human cell lines to evaluate mechanisms of action and safety profiles.
2) Pharmacokinetic studies – Examining how the body absorbs, distributes, metabolizes and eliminates the compounds.
3) Toxicology studies – Assessing potential toxic effects across multiple doses in two species.
4) Phase 1 clinical trials – Initial small trials in healthy humans to determine dosing and safety.
5) Phase 2/3 trials – Larger trials evaluating efficacy in patients for the intended condition (e.g. erectile dysfunction).
So while promising, these rat data represent an early step. Extensive further research is required to develop a safe and effective human therapy from Bulbine natalensis extract. The results justify continued investigation, but cannot directly translate to human use without more comprehensive evaluation in clinical studies.
Yakubu MT, Afolayan AJ. Effect of aqueous extract of Bulbine natalensis (Baker) stem on the sexual behaviour of male rats. Int J Androl. 2009 Dec;32(6):629-36. doi: 10.1111/j.1365-2605.2008.00910.x. Epub 2008 Aug 15. PMID: 18710410.
