Reactive Oxygen Species Production, Expression of Complement Regulator Genes and Phagocytosis in the Murine Microglial Cell after Administration of Beta-Amyloid(Aβ1-42) Protein

J Korean Neurol Assoc > Volume 23(1); 2005 > Article

Journal of the Korean Neurological Association 2005;23(1): 88-95.

아밀로이드베타단백(Aβ1-42)투여 후 마우스 소교세포의 활성산소종 생성과 보체조절유전자의 발현 및 탐식

최영숙, 이광수* 김상호

가톨릭대학교 의과대학 병리학교실, 신경과학교실*

Reactive Oxygen Species Production, Expression of Complement Regulator Genes and Phagocytosis in the Murine Microglial Cell after Administration of Beta-Amyloid(Aβ1-42) Protein

Young Sook Choi

Department of Pathology and Neurology*, The Catholic University of Korea College of Medicine, Seoul, Korea

Abstract

Background: Microglia is a primary cellular component of neuritic plaques in Alzheimer's disease. Beta amyloid deposits attract microglia and activate them to produce inflammatory mediators. The objectives of this study were to characterize activation of the microglia; production of reactive oxygen species (ROS), constitutive and upregulated expression of complement regulators, and intracellular localization of amyloid by phagocytosis.
Methods: BV-2 cells, mouse microglia cell line, were incubated for 3~18 hours with a single dose of 20 μM of aggregated Aβ1-42. ROS measurement was done with FACScan. Messenger RNA expressions of C1-INH, vitronectin, CD59, clusterin, factor H, and superoxide dismutase (SOD) were detected by RT-PCR. The intensity of bands from 6% polyacrylamide electrophoretic gel was analyzed by a bioimage analyzer. The intracellular localization of Aβ in the phagocytosed microglia was observed by transmission electron microscope.
Results: Aβ1-42 activates microglia with an increase of ROS production. Expression of mRNA for SOD was also increased. Messenger RNA for C1-INH and vitronectin were upregulated. Aβ fibrils were located in the phagosome of microglia.
Conclusions: Aβ activated microglia are playing dual roles as effector and scavenger cell, which as a result, may contribute to the chronic neuroinflammation of Alzheimer's disease. KeyWords:Amyloid beta-protein, C1 inhibitor, Microglia, Phagocytosis, Reactive oxygen species, Superoxide dismutase