|
KMID : 0359819940230040375
|
|
Journal of Korean Neurosurgical Society
1994 Volume.23 No. 4 p.375 ~ p.381
|
|
|
Antioxidant Action of Transthyretin in Human Cerebrospinal Fluid
|
|
양성렬
최기오/박종근/류문희/홍석노/김수한/안봉환/이제혁/이민화
|
|
|
Abstract
|
|
|
Protective effects of human cerebrospinal fluid antioxidants against enzyme inactivation caused by metal-catalyzed oxidation systems were investigated. When purified glutamine synthetase (GS) was incubated with human cerebrospinal fluid(CSF), the
enzyme
was progressively inactivated. Catalase and DETA could inhibit the enzyme inactivation by 50-80%. Small-molecular (Mr<-10.000) fraction of CSF inactivated the exogenous GS, but large-molecular(Mr>-10,000) fraction did not. The GS inactivation by
the
small-molecular fraction was also markedly inhibited by catalase and BDTA. These results suggested that metal-catalyzed oxidation is involved in the GS inactivation by the small-molecular fraction of CSF.
Dithiothreitol(DTT) was shown to inhibit almost completely the oxidative inactivation of GS by CSF. However, DTT inhibited only partially the oxidative inactivation of GS caused by small-molecular fraction of CSF. When large-molecular fraction of
CSF
was separated by anion-exchange HPLC chromatography, there was a peak of antioxidant activity inhibiting the small-molecular fraction-induced GS inactivation in the presence of DTT. The antioxidant activity was neutralized by monoclonal
antibodies
to
transthyretin. Purified transthyretin was found to efficiently inhibit ascorbate(Cu2+-induced GS inactivation in the presence of DTT. Uric acid and glucose did not show any protective effect on the Gs inactivation in the same condition.
The above results suggest that metal-catalyzed oxidation occurs normally in human CSF, and that transthyretin may play an important role as a CSF antioxidant in protecting proteins from metal-catalyzed oxidation.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
Listed journal information
|
|
 
|