We have prepared an aqueous extract of Achyranthes bidentata Blume, a Chinese medicinal herb commonly prescribed for arthritis treatment or immnopotentiation, and have found that Achyranthes bidentata extract promotes nerve growth and prevents neuronal apoptosis.
Aim of the study: To investigate the protective effect of Achyranthes bidentata extract against glutamate-induced neurotoxicity in primary culture of rat hippocampal neurons.
Materials and methods: We accomplished MTT assay for cell viability, Hoechst 33342 staining, and flow cytometry for cell apoptosis analysis to examine the effects of Achyranthes bidentata extract on glutamate-induced neurotoxicity, and also used Fluo 4-AM measurement, RT-PCR and Western blot analysis to determine the changes in intracellular calcium concentration [Ca(2+)](I), and mRNA and protein levels of Bcl-2, respectively, concurrently accompanied with the influences of Achyranthes bidentata extract.
Results: Achyranthes bidentata extract was found to inhibit glutamate-induced neuronal damage in a dose- and time-dependent manner. On the other hand, Achyranthes bidentata extract depressed glutamate-induced elevation of intracellular calcium concentration [Ca(2+)](i), and also antagonized glutamate-evoked decreases in Bcl-2 expression at mRNA and protein levels.
Conclusion: The results suggest that Achyranthes bidentata extract prevents glutamate-induced cell damage in primarily cultured hippocampal neurons by inhibiting an increase in [Ca(2+)](i), and reversing the down-regulation of Bcl-2.