Posted 25 April 2007 - 05:40 PM
New abstracts on Maca, below. There are variations of red,black, etc. One study shows it has estrogenic activity at the receptor. Seemingly many herbs that do are anticarcinogenic, anti-osteoporotic effects and lower cholesterol. There is some inhibition of prostatic hypertrophy...DHT inhibition? I'd like to discuss mechanisms.
Asian J Androl. 2007 Mar;9(2):245-51. Links
Effect of two different extracts of red maca in male rats with testosterone-induced prostatic hyperplasia.Gonzales GF, Vasquez V, Rodriguez D, Maldonado C, Mormontoy J, Portella J, Pajuelo M, Villegas L, Gasco M.
Biological and Physiological Sciences, Cayetano Heredia University, Lima, Peru. iiad@upch.edu.pe
AIM: To determine the effect of two different extracts of red maca in male rats. METHODS: Prostatic hyperplasia was induced in male rats with testosterone enanthate (TE). The study comprised six groups: one control group (group 1), one group treated with TE (group 2), two groups treated with TE and aqueous extract of red maca (groups 3 and 4), one group treated with hydroalcoholic extract of red maca (group 5) and one group treated with finasteride (0.1 mg, group 6). Differences in the aqueous extract dependent on the length of time of boiling, whether for 2 or 3 hours, for groups 3 and 4 was assessed. Extracts of red maca contained 0.1 mg of benzylglucosinolate. Thereafter, a dose-response effect of different doses of benzylglucosinolates (0.02-0.08 mg) in red maca extracts was assessed. RESULTS: Prostate weight was similar in rats treated with freeze-dried aqueous extract of red maca prepared after 2 and 3 hours of boiling. Freeze-dried aqueous extract of red maca, hydroalcoholic extract of red maca and finasteride reduced prostate weight in rats with prostatic hyperplasia. No difference was observed between the data obtained from aqueous extract or hydroalcoholic extract of red maca. A dose dependent reduction of prostate weight was observed with the increase of the dose of benzylglucosinolates in red maca extracts. CONCLUSION: The present study showed that hydroalcoholic or aqueous extract of red maca containing 0.1 mg of benzylglucosinolate can reduce prostate size in male rats in which prostatic hyperplasia had been induced by TE.
PMID: 17334591 [PubMed - in process]
Plant Foods Hum Nutr. 2007 Feb 27; [Epub ahead of print] Links
The Influence of Maca (Lepidium meyenii) on Antioxidant Status, Lipid and Glucose Metabolism in Rat.Vecera R, Orolin J, Skottova N, Kazdova L, Oliyarnik O, Ulrichova J, Simanek V.
Institute of Pharmacology, Medical Faculty, Palacky University, Hnevotinska 3, 775 15, Olomouc, Czech Republic, vecera@seznam.cz.
This work focused on the effect of maca on lipid, anti-oxidative, and glucose parameters in hereditary hypertriglyceridemic (HHTg) rat. Maca (1%) was administred to rats as a part of a high-sucrose diet (HSD) for 2 weeks. Rosiglitazone (0.02%) was used as a positive control. Maca significantly decreased the levels of VLDL (very low density lipoproteins), LDL (low density lipoproteins), and total cholesterol, and also the level of TAG (triacylglycerols) in the plasma, VLDL, and liver. Maca, as well as rosiglitazone, significantly improved glucose tolerance, as the decrease of AUC (area under the curve) of glucose showed, and lowered levels of glucose in blood. The activity of SOD (superoxide dismutase) in the liver, the GPX (glutathione peroxidase) in the blood, and the level of GSH (glutathione) in liver increased in all cases significantly. Results demonstrate that maca seems to be promising for a positive influence on chronic human diseases (characterized by atherogenous lipoprotein profile, aggravated
Andrologia. 2006 Oct;38(5):166-72. Links
Effect of Black maca (Lepidium meyenii) on one spermatogenic cycle in rats.Gonzales GF, Nieto J, Rubio J, Gasco M.
Instituto de Investigaciones de la Altura, Universidad Peruana Cayetano Heredia, Lima, Peru.
Lepidium meyenii (Maca) grows exclusively between 4000 and 4500 m above sea level in the Peruvian central Andes. The hypocotyls of this plant are traditionally used in the Andean region for their supposed fertility-enhancing properties. The hypocotyls have different colours. Of these, Black maca has better effects on spermatogenesis. The present study aimed to test the hypothesis that Black maca has early effects during a spermatogenic cycle (12 days) of male rats. For this, testicular spermatid, epididymal sperm and vas deferens sperm counts were measured after 1, 3, 5, 7 and 12 days of treatment with Black maca. Aqueous extract of Black maca was given orally by daily gavage at a dose of 2 g kg(-1). In a spermatogenic cycle, compared with day 1, daily sperm production (DSP) was lower at day 7 (control), whereas with Black maca, the difference was observed at day 12. Epididymal sperm count was higher in rats treated with Black maca at days 1, 3 and 7, but similar to controls at days 5 and 12; similarly sperm counts in vas deferens was higher in rats treated with Black maca in days 3, 5 and 7, but similar to controls at days 1 and 12. From this, it is suggested that first action of Black maca was at epididymal level increasing sperm count after 1 day of treatment, whereas an increase in sperm count was observed in vas deferens at day 3 of treatment. Finally, an increase in DSP was observed after 7 days of treatment with Black maca. Testicular testosterone was not affected after 7 days treatment with Black maca. In conclusion, Black maca affects sperm count as early as 1 day after beginning of treatment.
PMID: 16961569 [PubMed - indexed for MEDLINE]
Cell Biol Toxicol. 2006 Mar;22(2):91-9. Epub 2006 Mar 9. Links
The in vitro biological activity of Lepidium meyenii extracts.Valentova K, Buckiova D, Kren V, Peknicova J, Ulrichova J, Simanek V.
Institute of Medical Chemistry and Biochemistry, Faculty of Medicine, Palacky University, Olomouc. valentova@email.cz
The biological activity of methanolic and aqueous extracts from dehydrated hypocotyls of Lepidium meyenii (Brassicaceae, vernacular name "maca"), was studied on rat hepatocytes and human breast cancer MCF-7 cells. The extracts did not exhibit cytotoxicity in hepatocyte primary cultures up to 10 mg/ml as measured by the MTT viability test, and lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) leakage. Moreover, after 72 h, extracts inhibited LDH and AST leakage from the hepatocytes. When hepatocytes were intoxicated by t-butyl hydroperoxide, neither extract prevented oxidative damage. Both extracts showed weak antioxidant activity in the DPPH radical scavenging test with IC(50) values of 3.46 +/- 0.16 and 0.71 +/- 0.10 mg/ml, for aqueous and methanolic extracts, respectively. Thus, the observed effect on spontaneous enzyme leakage is probably mediated through mechanisms other than antioxidant activity. Both methanolic and aqueous extracts have shown estrogenic activity comparable with that of silymarin in MCF-7 cell line. Maca estrogenicity was exhibited in the range from 100 to 200 mug of extract per ml. The findings in the present study show that maca does not display in vitro hepatotoxicity. In contrast, a slight cytoprotective effect, probably not mediated by antioxidant capacity, was noted. Maca extracts exhibited estrogenic activity comparably to the effect of silymarin in MCF-7 cells.
J Ethnopharmacol. 2006 Apr 21;105(1-2):274-9. Epub 2006 Feb 8. Links
Effect of ethanol extract of Lepidium meyenii Walp. on osteoporosis in ovariectomized rat.Zhang Y, Yu L, Ao M, Jin W.
School of Life Science & Technology, Huazhong University of Science & Technology, 430074 Wuhan, PR China.
Maca (Lepidium meyenii Walp.) is a cruciferous plant from the Andes of Peru. The root of Maca is traditionally employed for its supposed properties in aphrodisiacs and improving fertility, it also has been widely used to help alleviate the symptoms of menopause. The purpose of this study was to evaluate the effect of ethanol extract of Maca on postmenopausal osteoporosis in ovariectomized rats. Female Sprague-Dawley rats were divided into four groups: Sham-operated and ovariectomized groups were fed with equivolume of distilled water, and the remaining ovariectomized groups were orally administrated with ethanol extract of Maca at 0.096 and 0.24 g/kg for 28 weeks. The findings derived from the basis of bone mineral density, biomechanical, biochemical and histopathological parameters indicated that higher dose of ethanol extract of Maca was effective in the prevention of estrogen deficient bone loss.
