EPC-K1 Prevents ONOO–-induced
Apoptosis
in Cerebellar Granule Neurons
WEI Tao-Tao, CHEN Chang, HUANG Yong-Jin, ZHAO Bao-Lu, HOU
Jing-Wu and XIN Wen-Juan*
( Institute of Biophysics, the Chinese Academy of Sciences, Beijing 100101,
China )
MORI Akitane
( Okayama University Medical School, Okayama 700, Japan )
Abstract The cytotoxic effect of
peroxynitrite on cerebellar granule neurons was studied. Exposure of cerebellar
granule neurons to 10 μmol/L peroxynitrite triggered apoptosis in vitro,
which was confirmed by both morphological(nuclear morphology observed by
fluorescence microscopy) and biochemical evidence(DNA fragmentation detected by
ELISA). Using ESR spin labeling technique, the alteration of biophysical
characteristics of neuronal cell membrane during the apoptotic process was
studied. The results indicate that after treatment with peroxynitrite, the
fluidity of both the surface layer and the deep layer of the neuronal cell
membrane decreased markedly, and the S/W ratio of the membrane protein thiol
groups increased significantly. Pre-treating cerebellar granule neurons with
antioxidant EPC-K1, a novel water-soluble derivative of vitamin C and vitamin
E, alleviated the oxidative injury and prevented cells from apoptosis.
Key Words Cerebellar granule neurons； apoptosis； peroxynitrite； antioxidant EPC-K1； ESR spin labeling
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