Tayler Catherine Kent

Introduction: Complementary and alternative medicines are used frequently, despite a lack of regulation and research into their safety and efficacy. Supplements marketed towards ‘boosting fertility’ are popular, but there is little research into their effects on spermatozoa. Previous studies looking at supplementation of sperm focus on motility rather than biochemical changes, and there is little research regarding potential toxicity in sperm.

Aim: The aim of this study was to determine whether in vitro incubation with maca root induced biochemical changes in ram spermatozoa.
Method: The function and metabolism of ram spermatozoa, incubated in media containing Lepidium meyenii (maca root) were investigated. At 0.5, 3 and 6 hours post-exposure, computer-assisted sperm analysis (CASA) and flow cytometry were used to assess motility, viability, acrosome reaction, membrane lipid disorder, mitochondrial superoxide production, intracellular reactive oxygen species (ROS) and DNA fragmentation.

Results: Treatment with maca induced acrosome reaction in treated cells (2.02% 0.39 n=3 p <0.001), but there was no difference in viability (73.3%1.49 n=180 p >0.05). There was an increase in mitochondrial superoxide production across all treatments and time points, and maca promoted membrane lipid disorder across all treatments (17.28%0.85 n= 54 p <0.001).

Discussion: The promotion of premature acrosome reaction in absence of an ovum may impact fertility of the male. It is posited that this may be driven by the oestrogenic activity of maca. Oestrogenic activity may also contribute to the higher membrane fluidity of treated sperm, as oestrogen can induce capacitation-like changes. Despite reported antioxidant activity of maca, the increase in mitochondrial superoxide production suggests increased oxidative stress in the presence of maca. Contrary to popular belief that these products enhance fertility, this research indicates that they should be used with caution due to possible negative effects on sperm, and lack of stringent safety data.

There is considerable interest in compounds that may improve sperm characteristics and therefore fertility, and the recent rise in popularity of complementary and alternative medicine has led to a demand for ‘natural’ alternatives to synthetic drugs, despite little research into the safety and efficacy of these compounds. Panax ginseng is a herb that has been utilised in Traditional Chinese Medicine for its supposed aphrodisiacal qualities, and has shown efficacy in improving reproductive function in laboratory rats. The main saponins found in ginseng, ginsenosides, are reported to exert the pharmacological effects of this herb.

Standardised extract from Panax ginseng (3.19 g) was administered orally to four rams every day for a 90-day period. Blood was collected periodically throughout the experiment and screened for ginsenosides using liquid chromatography-mass spectrometry (LC-MS). No ginsenosides were detected in blood from any treatment rams. After the completion of the 90-day trial, a second experiment was carried out, whereby two rams were given 5 times the original dose (15.94 g) of ginseng. LC-MS analysis determined that one ram had a serum concentration of 4.35 ng/mL Ginsenoside Rb1 at 30 minutes after treatment.

There was no significant difference in sperm motility between treatment and control groups, or over time. Treatment rams showed a significantly lower mean concentration, volume and total sperm count than controls. Both groups showed a significant improvement in semen volume and total sperm count over time.

This study highlighted the need for further study into the absorption and metabolism of ginseng in ruminants, and whether a higher dose will allow therapeutic levels to reach the circulation. External factors such as seasonal influence, as well as high individual variation, appear to have had more impact on sperm quality, and treatment with ginseng does not appear to have positively influenced sperm characteristics.