Rehmannia glutinosa activates intracellular antioxidant enzyme systems in mouse auditory cells.
Steamed roots of Rehmannia glutinosa (R. glutinosa) have been traditionally used in Oriental medicine for the treatment of auditory diseases such as tinnitus and hearing loss. To investigate whether the ethanol extract of steamed roots of R. glutinosa (SRG) increases activity of antioxidant enzymes and the level of glutathione (GSH), we measured activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione reductase (GR) and GSH level in HEI-OC1 cells after treatment with 5-50 microg/ml of SRG. The SOD and CAT activities were significantly increased in the presence of SRG compared to the control group. Maximal activities of SOD and CAT were observed in these cells exposed to 10 microg/ml of SRG. The GPX activity also increased dramatically in response to the treatment with SRG in a dose-dependent manner. The GR activity was only increased in the presence of 50 microg/ml of SRG compared to the control group. The level of GSH gradually increased in the presence of 5-50 microg/ml of SRG. In the cytotoxicity test, 5-50 microg/ml of SRG did not show any significant cytotoxicity. These results suggest that the traditional use of R. glutinosa for the treatment of auditory diseases may be explained, in part, by activation of intracellular antioxidant enzyme systems. Further studies are necessary to clarify the active constituents of SRG responsible for such biomolecular activities.
Yu
Hyeon-Hee
HH
Department of Food and Nutrition, Kunsan National University, South Korea.
Kim
Yeon-Hwa
YH
Jung
Su-Young
SY
Shin
Mee-Kyung
MK
Park
Rae-Kil
RK
So
Hong-Seob
HS
Kim
Ki-Young
KY
Lee
Da-Hong
DH
You
Yong-Ouk
YO
D000818:Animals; D002460:Cell Line; D006198:Hair Cells, Auditory / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D010088:Oxidoreductases / Q000096:biosynthesis*; D018517:Plant Roots; D032267:Rehmannia
D010088:Oxidoreductases