[Roles of bcl-2/bax expression and oligodendrocyte apoptosis in the pathogenesis of heroin-induced spongiform leucoencephalopathy].
OBJECTIVE
To investigate the role of oligodendrocyte apoptosis under the regulation of the bcl-2/bax protein expression in brain white matter in the pathogenesis of heroin-induced spongiform leucoencephalopathy (HSLE).


METHODS
Samples of frontal lobe, cerebellum, and corpus callosum were obtained from the brains during autopsy of 4 HSLE cases and 5 normal controls and underwent light microscopy and electron microscopy. Immunocytochemistry was used to detect the expression of myelin basic protein (MBP), caspase-3, bcl-2 protein, and bax protein.


RESULTS
Widespread demyelination was seen in the white matter of the frontal lobe, cerebellum and corpus callosum of the HSLE cases, most severely in the cerebellum. The levels of caspase-3 and bax expression of the HSLE group were significantly higher than those of the control group (both P <0.05) , however, the bcl-2 level of the HSLE group was no significantly different from that of the control group (P > 0.05).


CONCLUSIONS
Widespread demyelination in the white matter is a prevailed pathological change of HSLE. Oligodendrocyte apoptosis under induced by the decrease of bcl-2/bax ratio may contribute to the pathogenesis.
Yin
Rui-xue
RX
Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
Lu
Jiang-yang
JY
Lu
Bing-xun
BX
Chen
Qiang
Q
Yu
Jia
J
Cui
De-hua
DH
D000328:Adult; D000368:Aged; D017209:Apoptosis; D001344:Autopsy; D017825:Canavan Disease / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D005260:Female; D003932:Heroin; D006556:Heroin Dependence / Q000503:physiopathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D004676:Myelin Basic Protein / Q000096:biosynthesis; D009836:Oligodendroglia / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D051028:bcl-2-Associated X Protein / Q000096:biosynthesis*
D004676:Myelin Basic Protein; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D003932:Heroin