Neurodegenerative diseases are often associated with
oxidative damage in neuronal
cells . This study was conducted to investigate the neuro-protective effect of methanolic (MeOH) extract of
Perilla frutescens var. japonica and its one of the major compounds,
rosmarinic acid , under
oxidative stress induced by
hydrogen peroxide (H2O2) in C6
glial cells . Exposure of C6
glial cells to H2O2 enhanced
oxidative damage as measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium
bromide and thiobarbituric
acid -reactive substance assays. The MeOH extract and
rosmarinic acid prevented
oxidative stress by increasing
cell viability and inhibiting cellular
lipid peroxidation . In addition, the MeOH extract and
rosmarinic acid reduced H2O2-induced expression of
inducible nitric oxide synthase (iNOS) and
cyclooxygenase-2 (COX-2) at the transcriptional level. Moreover, iNOS and COX-2
protein expression was down-regulated in H2O2-indcued C6
glial cells treated with the MeOH extract and
rosmarinic acid . These findings suggest that P. frutescens var. japonica and
rosmarinic acid could prevent the progression of
neurodegenerative diseases through attenuation of neuronal
oxidative stress .