Protection of HT22 neuronal cells against glutamate toxicity mediated by the antioxidant activity of Pueraria candollei var. mirifica extracts
- 460 Downloads
Neuronal degeneration is known to be due to oxidative stress acting through a pathway involving the excessive activation of glutamate receptors. We studied the neuroprotection potential of an ethyl acetate–ethanol extract of Pueraria mirifica (P. candollei var. mirifica) root (PM extract). PM extract was evaluated for its antioxidant and neuroprotective activities against glutamate toxicity in mouse hippocampal HT22 neuronal cells. The extract at concentrations of 10 and 50 μg/ml exhibited considerable antioxidant activity with significant neuroprotection, based on the microscopic observations of cell morphology and the determination of cell viability and cell number. Studies of the possible mechanisms of action indicated that the neuroprotection exerted by PM extract was related to its scavenging activity against H2O2 and related reactive oxygen species. High-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC) analyses showed that the extract contained daidzein and genistein as identified constituents, as well as additional components with antioxidant activity. While daidzein and genistein individually and in combination were observed not to be neuroprotective, we propose that the antioxidant and neuroprotective activities of PM extract are derived from the combined properties of its constituents.
KeywordsPueraria mirifica Partially purified extract Antioxidant activity Neuroprotection Scavenging activity HT22 neuronal cells
This work was financially supported by the Thailand Research Fund through the Royal Golden Jubilee Ph.D. Program (grant no. PHD/0104/2546) to A.S. and W.D. and the Thailand National Center for Genetic Engineering and Biotechnology (BIOTEC) (grant no. 2/2546). We would also like to thank Khao-La-Or Laboratories, Ltd., Bangkok, Thailand, for supplying the Pueraria mirifica material.
- 2.Muangman V, Cherdshewasart W (2001) Clinical trial of the phytoestrogen-rich herb, Pueraria mirifica as a crude drug in the treatment of symptoms in menopausal women. Siriraj Hosp Gaz 53:300–309Google Scholar