“In vivo” and “in vitro” neuroprotectant effect of lipophilic compounds from Lepidium meyenii (Maca)

Abstract

Neuron death is one of the major pathological factors in stroke and neurodegenerative diseases. However, the drugs targeting cell death remain limited. While the constituents of Maca, a South American plant, are reported to possess various pharmacological properties, no studies have been undertaken to determine their efficacy as neuroprotectants. The aim of this study was to test the Maca's lipophilic constituents in two experimental models: in vivo, in a model of permanent cerebral ischemia, and in vitro in a NMDA‐induced cytotoxicity assay utilizing crayfish neurons. The pentane extract of the root was evaluated in rats prior to and following cerebral ischemia, and 24 hours later TTC staining of viable tissue was used to quantify infarct volumes. Infarct volumes were significantly decreased for the lowest dose (3 mg/kg) and significantly increased for the higher doses (10 & 30 mg/kg) compared to control. Extract fractionation with a silicagel preparative column was guided by HPLC. Crayfish neurons were subjected to NMDA as a neurotoxic agent and treated with vehicle, total pentane extract, or the fractions eluted with a mobile phase (2% methanol in dichloromethane). Neuroprotection by the most lipophilic compounds was demonstrated. These results suggest a potential application of the lipophilic compounds from Maca as neuroprotectants. This research is supported by the MCPHS.