Effect of Lepidium meyenii (maca) on testicular function of mice with chemically and physically induced subfertility

Phytochemical Evaluation of Lepidium meyenii, Trigonella foenum-graecum, Spirulina platensis, and Tribulus arabica, and Their Potential Effect on Monosodium Glutamate Induced Male Reproductive Dysfunction in Adult Wistar Rats

Monosodium glutamate (MSG), a sodium salt derived from glutamic acid, is widely used in commercial food products to improve taste, quality, and preservation. However, its consumption may have detrimental effects on male reproductive function. Nevertheless, plant extracts, such as Lepidium meyenii (Maca), Trigonella foenum-graecum (Fenugreek), Spirulina platensis (Spirulina), and Tribulus arabica (Tribulus), may ameliorate these adverse effects. To this effect, the phytochemical properties of Lepidium meyenii, Trigonella foenum-graecum, Spirulina platensis, and Tribulus arabica were assessed, and their potential impact on MSG-induced impairment of reproductive parameters was examined. The phytochemical composition (steroids, terpenes, phenols, flavonoids) of the plants was profiled through spectrophotometry and the antioxidant activity was assessed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. Thirty-six male Wistar rats were divided into six groups at random: a control group receiving distilled water, and five experimental groups (MSG, Maca, Fenugreek, Spirulina, and Tribulus) receiving 900 mg/kg/day of MSG dissolved in water for 45 days. Subsequently, the animals in the experimental groups were administered 500 mg/kg/day of the respective plant extract via oral gavage for an additional 35 days, while the MSG group continued to receive water only. Following the treatment period, the animals were sacrificed, and their reproductive tract organs were collected, weighed, and subjected to further analysis. Phytochemical analysis revealed the presence of diverse bioactive elements in the plant extracts, including phenolic and flavonoid compounds. Exposure to MSG negatively impacted total and progressive sperm motility, which was ameliorated by Lepidium meyenii treatment. Sperm morphology showed no significant differences among groups. Treatment of the phytochemical agents diminished histomorphometric alternations of the testicular length, germinal epithelium height, and number of cells in seminiferous tubules, which were caused by the initial administration of MSG. Testosterone and LH levels were reduced in the MSG group but improved in extract-treated groups. The study suggests Lepidium meyenii as a potential remedy for reproductive dysfunction. However, further investigation into its mechanisms and human safety and efficacy is warranted.

A novel approach of using Maca root as a radioprotector in a rat testicular damage model focusing on GRP78/CHOP/Caspase-3 pathway

PURPOSE

Despite the effectiveness of ionizing radiation in treating cancer, it can damage healthy tissues in the vicinity. Due to the high radio-sensitivity of testicular tissues, radiation therapy may affect spermatogenesis, which may result in infertility. Hence, in this study testicular damage model is constructed to investigate the mitigation effect of Maca root powder and its potential radioprotective activity through both oxidative and endoplasmic reticulum (ER) stresses, besides the apoptotic pathway.

METHODS

Male albino rats were exposed to 6Gy of whole-body gamma radiation single dose. Maca root powder (1 g/kg b.wt./day, by oral gavage) was administered for a week before irradiation, then d-galactose (300 mg/kg, by oral gavage) and Maca daily for another week.

RESULTS

Gamma radiation and d-galactose revealed a significant decrease in serum testosterone, sperm count, and motility and higher percentage of the sperm head abnormality, while Maca root treatment maintained all sperm morphology parameters. Maca root treatment demonstrated a notable defense against radiation-induced oxidative stress and ameliorated malonaldehyde (MDA), reactive oxygen species (ROS), nitric oxide (NO), glutathione-S-transferase (GST) levels, reduced glutathione (GSH), oxidized glutathione (GSSG) and the ratio of GSH/GSSG in testis tissues. Exposure to gamma rays and d-galactose displayed a significant elevation in GRP78, CHOP, total caspase-3 as well as active (cleaved) caspase-3 levels, whereas treatment with Maca significantly reduced the ER and apoptotic markers levels. Also, Maca improved the histological changes of the disorganized seminiferous tubules induced by irradiation.

CONCLUSION

Our findings show for the first time that Maca has a protective effect on male reproductive damage induced by radiotherapy. Maca root reveals anti-apoptotic effect and protection against testicular damage via GRP78/CHOP/caspase-3 pathway.

Influence of dietary supplementation with Lepidium meyenii (Maca) on sperm quality in dogs

Maca is a traditional Andean crop used as a nutraceutical for the fertility-enhancing properties that are linked with antioxidant activity. The aim of this study was to evaluate, for the first time, the potential beneficial effects of oral Maca (Lepidium meyenii or Lepidium peruvianum) supplementation in improving reproductive performance in male dogs. Forty-eight male dogs of different breeds were enrolled in the study, fed the same maintenance diet, and exposed to the same environmental conditions. The subjects were divided into four groups of 12 dogs each: Subfertile treatment group, Subfertile control group, Normofertile treatment group, and Normofertile control group. The dogs in the treatment groups received Lepidium meyenii in their diet in a capsule formulation [75 mg/kg Maca extract 10:1, thickening agent (hydroxypropyl methylcellulose), ground rice], while the control groups received placebo capsule (starch). For each subject included in the study, the spermiogram was analyzed at three time points of the sperm cycle: at day 0 (T0), day 31 (T31), and day 62 (T62). Dietary supplementation with Maca in subfertile subjects resulted in a significant increase in ejaculate volume and total sperm count compared to the control group. This increase was also observed in normofertile subjects in the treatment group. In addition, total and progressive motility as well as sperm morphology were significantly improved in the groups treated with Maca compared to the control groups. The results thus highlight, for the first time, the potential efficacy of supplementation with 75 mg/kg of Maca extract daily in improving semen quality in dogs.

Effect of Atomized Black Maca (Lepidium meyenii) Supplementation in the Cryopreservation of Alpaca (Vicugna pacos) Epididymal Spermatozoa

Artificial insemination is an important assisted reproductive technology that has been applied in several mammalian species. However, successful cryopreservation of semen of South American camelids has been limited, hindering the commercial application of artificial insemination in alpaca species. In this scenario, the addition of antioxidants to semen extenders provides a strategy to improve the freezability of mammalian sperm. Bioactive metabolites from natural extracts of black maca have shown valuable antioxidant properties. Thus, the objective of this study was to evaluate the effect of the addition of atomized black maca in the freezing medium of epididymal spermatozoa of alpacas. Fifteen pairs of epididymis were collected from a local slaughterhouse. Each sample was divided into six groups: (1) fresh, (2) yolk medium (YM), (3) 10 mg/mL maca, (4) 20 mg/mL maca, (5) 30 mg/mL maca, and (6) resveratrol (as an antioxidant control). Sperm cryopreservation was performed through the slow freezing method. Markers associated with functionality, such as motility, viability, and plasma membrane integrity, as well as markers associated with oxidative damage, such as DNA integrity, total ROS production, and mitochondrial function, were analyzed. The results show that the supplementation with black maca (20 mg/mL) improved the sperm motility, viability, plasma membrane integrity, and mitochondrial function evaluated according to an index of formazan deposits. Similarly, the ROS production decreased with maca at 20 mg/mL, although the DNA integrity did not show any differences among the groups. These results suggest that maca at 20 mg/mL has cytoprotective effects during freezing/thawing of epididymal sperm of alpaca species. Further research will be focused on assessing the effects of maca supplementation on semen extenders by using biomolecular markers (proAKAP4) associated with fertility.

Maca (Lepidium meyenii Walp.) on semen quality parameters: A systematic review and meta-analysis

Background: This study aimed to examine the evidence for the effect of Lepidium meyenii Walp. [Brassicaceae] (L. meyenii W.), known as maca, on improving semen quality. Methods: Nine databases were searched for randomized controlled trials (RCTs) that examined the parameters for improvements in semen quality, regardless of the type of L. meyenii W. The risk of bias (ROB) among the studies was evaluated according to the Cochrane ROB tool. Results: Five RCTs met all of the inclusion criteria. Three RCTs showed mixed efficacy of maca in improving semen quality parameters, including sperm concentration and sperm motility, in men experiencing infertility. The meta-analysis also failed to show the efficacy of maca in increasing the sperm concentration compared to the placebo (weighted mean difference, 2.22, 95% confidence interval -2.94 to 7.37, p = 0.4). Two other RCTs also showed mixed effects of maca on several semen quality parameters in healthy men. Conclusion: The evidence from the included studies suggests unclear effects of maca on semen quality parameters in both men experiencing infertility and healthy men. However, the total number of RCTs and the total sample size were too small to draw firm conclusions.

First study of in vitro protective effect of Lepidium meyenii (Maca) on frozen–thawed bovine spermatozoa

Background and Aim:

Lepidium meyenii Walp (Maca) is an herbaceous plant that grows in the Peruvian Andes and it has been widely used as a nutritional supplement and fertility enhancer and has been used in the treatment of a variety of diseases, such as rheumatism, respiratory disorders, and anemia. The most notable feature of Maca is its potent antioxidant capacity, which helps in the scavenging of free radicals and protection of cells from oxidative stress. This study aimed to evaluate the in vitro effect of Maca extract on thawed sperm cells from bulls.

Materials and Methods:

Three dilutions of 1, 10, and 100 mg/mL of Maca extract were incubated with frozen–thawed bovine semen and analyzed at 1, 3, and 24 h of exposure time, evaluating the activity of the extract on the DNA, motility, morphology, viability, integrity of the membrane and acrosome of spermatozoa.

Results:

The Maca extract improved the studied sperm parameters of motility, acrosome integrity, vitality, and DNA integrity of sperm cells at a concentration of 10 mg/mL, and at 1 mg/mL, an improvement was observed in the morphology and integrity of the membrane. However, the best activity of the Maca extract was observed on the DNA integrity of the sperm, which was effective at the three concentrations evaluated after 24 h of incubation.

Conclusion:

The results indicate that L. meyenii can help in maintaining spermatozoa cellular integrity after the frozen–thaw process, especially in the protection against DNA fragmentation. Therefore, Maca would be a feasible supplementation to protect sperm to maintain their fertile ability after thawing.

Evaluation of the effect of Lepidium meyenii Walpers in infertile patients: A randomized, double-blind, placebo-controlled trial

Male infertility refers to the inability to conceive a natural pregnancy in a fertile female, and approximately 15% of reproductive‐aged couples worldwide face this problem. Several plants were used to treat fertility disorders and, among them, Lepidium meyenii, a folk medicament of Andean regions, is still used to enhance vitality and treat sterility in humans and domestic animals. The aim of the study was to evaluate the effects of L. meyenii Walpers on infertile patients by a randomized, double‐blind, placebo‐controlled trial. Fifty patients suffering from various reproductive‐related problems were enrolled for 16 weeks to evaluate the effect of yellow maca on semen quality and serum hormone levels. Treatment with maca improved the percentage of sperm concentration by 40%, whereas the placebo improved by 76% after 8 and 16 weeks of treatment, but the results were statistically non‐significant. No statistically significant change in hormone levels was reported by using maca, except a decrease in the level of free testosterone. Results are not sufficient to assess the efficacy of maca on male fertility. Further investigation and trials are required to obtain conclusive results.

Rescue and Conservation of Male Adult Alpacas (Vicugna pacos) Based on Spermatogonial Stem Cell Biotechnology Using Atomized Black Maca as a Supplement of Cryopreservation Medium

This is the first time that testicular tissue (n = 44) and isolated testicular cells (n = 51) were cryopreserved from alpaca testes 24 h postmortem. For this purpose, internally designed freezing media and cryopreservation protocols were used. Testicular tissue fragments (25 mg) and isolated testicular cells were frozen in MTDB (trehalose and black maca), MTD (trehalose), MSDB (sucrose and black maca), and MSD (sucrose) media. Isolated spermatogonial cells were cryopreserved in two ways, before and after proliferation in vitro. After cryopreservation, the percentage of cell viability in Group 1 (>50% of cell viability) by trypan blue did not show differences within each group (p > 0.05) but showed significant differences when comparing fragments with isolated cells (p < 0.05). Spermatogonial stem cells (SSC) were identified by flow cytometry as strong Dolichos biflorus agglutinin (sDBA) and mitochondrial activity of SSC as strongly positive for MitoSense (sMitoSense+) in intact mitochondria cells, weakly positive for MitoSense (wMitoSense+) in early apoptosis, and necrosis with 7-Aminoactinomycin-D positive (7-AAD). After freezing, in Group 1M (≥30% sMitoSense+), the fragments did not show differences between the media (p > 0.05), but in the isolated cells frozen in MSDB medium, 63.68 ± 8.90% (p < 0.05). In Group 2M (<30% sMitoSense+), necrosis (7AAD+) in MSDB medium was 27.03 ± 5.80%, and necrosis in isolated cells was 14.05 ± 9.3% with significant differences between these groups (p < 0.05); in sMitoSense+, the isolated cells (34.40 ± 23%) had a higher percentage than the fragments (12.4 ± 5.2) (p < 0.05). On the other hand, MSDB and MSD media were significantly higher for isolated cells than for fragments in sDBA+ (p < 0.05). On the other hand, the SSC (sDBA+) had significant differences (p < 0.05) between fresh cells 7.43 ± 1.3% (sDBA+) compared with those cryopreserved in MSDB medium 1.46 ± 0.34% (sDBA+). Additionally, the proliferated and cryopreserved SSC 6.29 ± 1.17% (sDBA+) did not show significant differences concerning the fresh cells (p > 0.05). In conclusion, the black maca showed antioxidant properties when it was included in the freezing medium and, therefore, improved the SSC's conservation of the alpaca. Furthermore, the proliferation of isolated cells in vitro produces a higher amount of SSC after thawing them for further preclinical or clinical work.

Role of Antioxidant Natural Products in Management of Infertility: A Review of Their Medicinal Potential

Infertility, a couple's inability to conceive after one year of unprotected regular intercourse, is an important issue in the world. The use of natural products in the treatment of infertility has been considered as a possible alternative to conventional therapies. The present study aimed to investigate the effects and the mechanisms of various natural products on infertility. We collected articles regarding infertility and natural products using the research databases PubMed and Google Scholar. Several natural products possess antioxidant properties and androgenic activities on productive factors and hormones. Antioxidants are the first defense barrier against free radicals produced by oxidative stress (OS). They remove reactive oxygen stress (ROS), reducing insulin resistance, total cholesterol, fat accumulation, and cancer growth. Moreover, various natural products increase endometrial receptivity and fertility ability showing androgenic activities on productive factors and hormones. For example, Angelica keiskei powder and Astragalus mongholicus extract showed anti-infertility efficacies in males and females, respectively. On the other hand, adverse effects and acute toxicity of natural products were also reported. Tripterygium glycoside decreased fertility ability both in males and females. Results indicate that management of infertility with natural products could be beneficial with further clinical trials to evaluate the safety and effect.

Lepidium meyenii (Maca) in male reproduction

Lepidium meyenii (Maca) is an edible root plant that grows in the Andean region of Peru. For centuries, the plant has been used as a dietary supplement for its nutritional and therapeutic properties. Maca are rich in high value nutritional elements and secondary metabolites (macaridine, macamides and glucosinolates) with high biological activity. Several studies demonstrated various biological effects of Maca mainly in the field of fertility. The aim of this review is to summarize the state of knowledge on the properties of Maca on male reproduction. Literature data was performed in PubMed with researches published from 2000 to 2019. The research showed results related to the effects of Maca on the quality and quantity of the semen, sexual behaviour and disorders of the male genital tract. Despite the numerous studies carried out on different animal species, further research is needed to clarify the mechanisms of action of Maca.

Myrciaria dubia "camu camu" flour as a magnetoprotector in male mouse infertility

Possible adverse effects of extremely low frequency magnetic fields (ELF-MF) are linked to a decrease of antioxidant defenses and the production of free radicals. The increase of free radicals affects the mitochondrial functionality inducing apoptosis, which affects the phosphorylation and generation of key ATP in fertilization. Myrciaria dubia, known as "camu camu," is a fruit with high levels of ascorbic acid, which exerts an important antioxidant function in the prevention of premature cell damage. In this study, the effect of Myrciaria dubia flour on oxidative damage produced by ELF-MF (610 μT) was evaluated by detecting the activity of endogenous mitochondrial oxidoreductase enzymes in a complete sperm cycle of mice. We found that the MF caused a significant (P < 0.05) decrease in sperm quality, whereas the groups supplied with Myrciaria dubia flour (50 and 75 mg/kg of body mass) in ELF-MF exposure showed a significant recovery (P < 0.05) in parameters of viability, percentage of plasma membrane integrity and mitochondrial activity, and index of epidymal sperm. This suggests that Myrciaria dubia flour would have an antioxidant activity that counteracts the damaging effects of ELF-MF in spermatogenesis and could be used as a natural ELF-MF protector. Bioelectromagnetics. 40:91-103, 2019. © 2019 Bioelectromagnetics Society.

Is the hype around the reproductive health claims of maca (Lepidium meyenii Walp.) justified?

ETHNOPHARMACOLOGICAL RELEVANCE

Maca - Lepidium meyenii Walp. has been cultivated and used by Andean people for over 1300-2000 years in Peru as food and medicine. Starting in the late 1990's it has developed into an important herbal medicine in China and is now cultivated there widely, too AIM OF STUDY: This study aims to provide an insight into the emergence of maca on the global market as an alternative remedy to treat reproductive health related problems in both men and women and to critically assess these health claims.

METHODOLOGY

A search of electronic databases such as EMBASE and a hand-search was done to acquire peer-reviewed articles and reports about maca.

RESULTS AND DISCUSSION

Lepidium meyenii is used traditionally as a tonic, fertility enhancer for both humans and cattle, and to treat a variety of ailments such as rheumatism, respiratory disorders and anaemia among others. Maca root is cooked, baked, fermented as a drink and made into porridge. In the last twenty years, maca was introduced onto the global market and demand has dramatically grown over this time with its promotion on the internet, as the 'Peruvian Ginseng' for libido and fertility enhancement. It has also been said to treat menopausal symptoms, erectile dysfunction and benign prostatic hyperplasia. The sky-rocketing demand for the plant has seen a shift from traditional cultivation methods to mass production practices with the use of fertilisers and also pesticides; as maca is now grown in areas other than the Andes such as in the Yunnan province in China. This can potentially affect the phytochemistry and composition of the plant and thus, the quality, safety and efficacy of maca products. Meanwhile, research into maca's medicinal properties has followed the spike in popularity of maca and has been focused mainly on maca's aphrodisiac and fertility enhancing properties. So far, the in vivo studies and clinical trials conducted have yielded inconclusive results. Some of the key limitations reside in methodology and sample size. Chemical profiling, led to the discovery of new compounds unique to maca, such as, 'macamides' and also other active metabolites like the glucosinolates; to which the medicinal effects of maca have been ascribed but cannot be confirmed due to lack of data.

CONCLUSIONS

To date, the health claims of maca cannot be fully supported from a scientific standpoint and more research is needed. It appears that the indigenous local knowledge about the health benefits of maca has been dragged out of context to fit the demands of a growing market for herbal remedies. This globalisation (or hype esp. in China) also has had serious consequences for the local producers in Peru. The lack of protocols to regulate the production and marketing of maca during this rapid expansion, poses a threat to both the safety of consumers and the sustainability of supply.