Neuroprotective effect of Chunghyuldan (Qing Xue Dan) on hypoxia-reoxygenation induced damage of neuroblastoma 2a cell lines.

OBJECTIVES

Chunghyuldan (CHD), a combinatorial drug that has anti-hyperlipidemic and antiinflammatory activities, has been shown to reduce infarct volume in a focal ischemia-reperfusion rat model. To explore the molecular basis of CHD's neuroprotective effect, we examined whether CHD shows a cell-protective activity and has a regulatory effect on Bax and/or B-cell leukemia/lymphoma 2 (Bcl-2) expression in mouse neuroblastoma 2a (N2a) cells subjected to hypoxia-reoxygenation (H/R).

METHODS

In order to evaluate the effects of CHD on the cytotoxicity induced from hypoxia or H/R condition, lactate dehydrogenase (LDH) assay was performed. To explore whether the suppression of neural damage when pre-treated with CHD is associated with its anti-apoptotic effect, the CHD effect on the expression of Bcl-2 and Bax was analyzed by Western blotting analysis.

RESULTS

Cytotoxicity of N2a cell line was slightly increased in 42 h hypoxia condition and dramatically increased under the H/R condition. CHD treatment markedly decreased the cytotoxicity in both conditions (P<0.01, P<0.05). H/R markedly increased the expression of the pro-apoptotic protein, Bax, but slightly increased the expression of the anti-apoptotic protein, Bcl-2, compared with the normoxia or hypoxia group. CHD significantly decreased Bax expression (P<0.01) and slightly decreased Bcl-2 expression (P>0.05), resulted in a reduction of Bax/Bcl-2 ratio in N2a cells subjected to H/R.

CONCLUSION

CHD has neuroprotective effect in N2a cells subjected to H/R, which might be derived at least in part from its ability to decrease the expression of the pro-apoptotic protein, Bax.