The Research on the Impact of Maca Polypeptide on Sport Fatigue

Lepidium meyenii (Maca) Roots: UPLC-HRMS, Molecular Docking, and Molecular Dynamics

Lepidium meyenii or Maca is widely cultivated as a health care food supplement due to its nutritional and medicinal properties. Although there are a few in-depth studies evaluating Maca antihypertensive effects, the correlations between the chemical constituents and bioactivity of the plant have not been studied before. Thus, the roots were extracted using different solvents (aqueous, methanol, 50% methanol, and methylene chloride) and investigated for their antihypertensive and antioxidant activities through several in vitro assays. The methanolic extract exhibited the best renin and angiotensin converting enzyme (ACE) inhibitory activities with IC₅₀ values of 24.79 ± 1.3 ng/mL and 22.02 ± 1.1 ng/mL, respectively, along with the highest antioxidant activity. In total, 120 metabolites from different classes, e.g., alkylamides, alkaloids, glucosinolates, organic acids, and hydantoin derivatives, were identified in the methanolic extract using ultrahigh-performance liquid chromatography/high-resolution mass spectrometry (UPLC/HRMS). Molecular docking simulations were used to investigate the potential binding modes and the intermolecular interactions of the identified compounds with ACE and renin active sites. Glucotropaeolin, β-carboline alkaloids, succinic acid, and 2,4-dihydroxy-3,5-cyclopentyl dienoic acid showed the highest affinity to target the ACE with high docking scores (S ranging from -35.32 to -22.51 kcal mol^-1) compared to lisinopril (S = -36.64 kcal mol^-1). Interestingly, macamides displayed the greatest binding affinity to the active site of renin with docking scores (S ranging from -22.47 to -28.25 kcal mol^-1). Further, β-carbolines achieved docking scores comparable to that of the native ligand (S ranging from -13.50 to -20.06 kcal mol^-1). Molecular dynamics simulations and MMPBSA were also carried out and confirmed the docking results. Additionally, the computational ADMET study predicted that the compounds attaining promising docking results had proper pharmacokinetics, drug-likeness characteristics, and safe toxicological profiles. Ultimately, our findings revealed that Maca roots could be considered a promising candidate as an antihypertensive drug.

Chemical composition and health effects of maca (Lepidium meyenii)

Maca (Lepidium meyenii Walpers) has emerged as a popular functional plant food due to various claimed health effects. This review details the major (i.e., starch, dietary fiber, and protein) and minor constituents (i.e., minerals, non-starch polysaccharides, polyphenols (flavonolignans), macaenes, macamides, glucosinolates, and alkaloids) of maca (root and aerial parts). Diverse health effects of maca are also summarized. Various bioactivities of maca include enhanced reproductive health, antifatigue, antioxidation, neuroprotection, antimicrobial activity, anticancer, hepatoprotection, immunomodulation, and improving skin health and digestive system's function. Plant genetics, botanical parts, processing, extraction, and experimental protocols represent the major factors affecting the chemical composition, physicochemical attributes, and health effects of maca-based products. However, clinical studies to support the claimed health effects of maca and related mechanisms appear to be lacking. Product innovation and diversification in food and non-food utilization of different parts of maca to maximize the value perceptions are suggested.

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.

Retraction Notice: The Research on the Impact of Maca Polypeptide on Sport Fatigue

[This retracts the article on p. 322 in vol. 9.].