Dose–response effects of Lepidium meyenii (Maca) aqueous extract on testicular function and weight of different organs in adult rats
Introduction
Maca (Lepidium meyenii Walp) from the Brassicaceae family grows exclusively between 4000 and 4500 m above sea level at the Peruvian central Andes (Gonzales et al., 2001b). According to traditional beliefs reported by Spaniard chronicles in the XVII century (Cobo, 1956), Maca is a plant that enhances fertility in humans and domestic animals, which tends to be reduced after acute exposure to high altitudes.
The first evidence that Maca improved spermatogenesis was reported in male rats (Gonzales et al., 2001b). Thereafter, Gonzales et al. (2001a) demonstrated that Maca (1.5 or 3.0 g) also improved sperm count and sperm motility in normal men without affecting serum testosterone and estradiol levels.
We have studied the effect of aqueous extract of dried Maca hypocotyls in doses up to 2 g/kg body weight (Gonzales et al., 2001b, Gonzales et al., 2004). It is important to know what for effect are elicited with higher doses and how safe is consuming high amounts of Maca. A dose–response study was undertaken to determine the effect of an aqueous Maca extract at doses up to 5 g/kg body weight in male rats, corresponding to 11 g dry Maca hypocotyls/kg body weight.
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Animals
Three-month-old male rats from the Holtzman strain obtained at the animal house of the Universidad Peruana Cayetano Heredia were used. Rats were allotted randomly into five groups according to the extract dose administered.
Rats were housed 4–6 per cage and maintained at 22 °C with a 12-h light:12-h dark cycle. Rats were provided with Purina Laboratory chow and tap water ad libitum.
Animals were managed and experiments were performed in accordance with the internationally accepted principles for
Effect of Maca on body and organ weights in male rats
After 7 days of treatments, all groups, except that treated with 5 g extract/kg increased body weight. Final body weight was similar in control rats and rats-treated with 0.01–1.0 g extract/kg. There was no evidence of toxicity after oral administration of Maca extract in doses up to 5 g extract/kg. Regarding organ weight, only seminal vesicle weight was significantly reduced at doses of 0.01 g extract/kg (from 1.01 ± 0.04 to 0.45 ± 0.15; P < 0.01) and 0.10 g extract/kg (from 1.01 ± 0.04 to 0.57 ± 0.11; P <
Discussion
Herbal medicine is used by up to 80% of the population in the developing countries (Hilaly et al., 2004). In the United States, approximately one-quarter of adults reported use of herbs to treat a medical illness within the past year (Bent and Ko, 2004). Despite the widespread use, few scientific studies have been undertaken to ascertain the safety and efficacy of traditional remedies (Hilaly et al., 2004).
In the present study, Maca, a cultivated plant from highlands of Peru, administered to
Acknowledgement
The study was supported by a grant from the Vicerrectorado de Investigación at the Universidad Peruana Cayetano Heredia.
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2019, Food ChemistryCitation Excerpt :Scientific understanding is still unavailable in terms of (1) principle active components of maca responsible for the observed physiological beneficial effects (only few components were tentatively proposed) (Table 4); (2) mechanisms of action involved in those positive physiological responses in vivo; and (3) optimization of in vivo evaluation systems (Beharry & Heinrich, 2018). Beneficial effects of maca powder or extract administration on spermatogenesis were observed in various male animal models, including Holtzman male rats (the mostly used rodent model), Ansell male mice, peri-pubertal breeding bulls, BALB/c male mice, Swiss strain mice, and male Saint Croix rams ( Gonzales, Ruiz et al., 2001, 2003, 2004, Gonzales, Rubio et al., 2006, Gonzales, Nieto et al., 2006; Chung et al., 2005; Gasco et al., 2007; Gonzales, 2012; Ray et al., 2015). Secondary metabolites such as phenolics were possible spermatogenesis promoters (Inoue, Farfan, & Gonzales, 2016; Yucra et al., 2008).
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2019, Journal of Pharmaceutical and Biomedical AnalysisCitation Excerpt :It is a kind of edible and medicinal product, which not only has an abundance of nutrition but also has many functional characteristics. Decades over researches have confirmed that it can be a diminution of sexual dysfunction, a lessening of menopausal symptoms [1,2] as well as an enhancer of libido and fertility [3–7]. The tuber of Maca mainly consists of protein, lipid, carbohydrate, mineral composition [8] and the secondary metabolites like phytosterols, fatty acid, alkaloids, glucosinolates and macamides [9].
Is the hype around the reproductive health claims of maca (Lepidium meyenii Walp.) justified?
2018, Journal of EthnopharmacologyCitation Excerpt :The lack of standard quality control protocols in place (Li et al., 2001; Shu et al., 2015) renders the quality, efficacy and safety of available maca products questionable and poses a threat to consumers worldwide. In some studies, the preparation of aqueous extract of maca for in vivo study purposes was claimed to reflect a traditional method of preparing maca done by boiling and then filtrating (Gonzales et al., 2001b, 2004, 2006a, 2005; Chung et al., 2005; Bustos-Obregon et al., 2005; Rubio et al., 2006). Other extract types have also been investigated and may help give an indication as to which bio-active compounds are responsible for the observed effects of maca on male fertility (Zheng et al., 2000; Cicero et al., 2002; Gonzales et al., 2003b, 2007, 2008; Yucra et al., 2008; Inoue et al., 2016; Ohta et al., 2016; Zhang et al., 2016).
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