Systemic lipopolysaccharide (LPS)-induced microglial activation results in different temporal reduction of CD200 and CD200 receptor gene expression in the brain.
LPS activates microglia, which are normally maintained in a quiescent state by CD200-CD200 receptor (CD200R) interaction. MAC-1 (a microglia marker) mRNA expression was increased in mice brains up to 1 year post LPS administration (i.p.). Minocycline treatment did not prevent LPS (5 mg/kg)-induced increase in MAC-1 mRNA but reduced that induced by 0.1 mg/kg LPS. CD200R mRNA decreased starting at 4 h, whereas CD200 mRNA increased at 4 h and decreased at 1 year post LPS inoculation. Thus, LPS-induced changes in CD200-CD200R equilibrium might keep microglia chronically activated. Minocycline does not effectively inhibit microglia activation induced by high-dose LPS.
Masocha
Willias
W
Department of Applied Therapeutics, Faculty of Pharmacy, Kuwait University, Safat, 13110, Kuwait. masocha@hsc.edu.kw
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015703:Antigens, CD / Q000187:drug effects / Q000378:metabolism*; D001921:Brain / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D015870:Gene Expression / Q000187:drug effects; D008070:Lipopolysaccharides; D016177:Macrophage-1 Antigen / Q000187:drug effects / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D017628:Microglia / Q000187:drug effects / Q000276:immunology*; D008911:Minocycline / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
D000900:Anti-Bacterial Agents; D015703:Antigens, CD; C492346:CD200 receptor, mouse; D008070:Lipopolysaccharides; D016177:Macrophage-1 Antigen; D008562:Membrane Glycoproteins; D008911:Minocycline; C042739:antigens, CD200