Infection and inflammation decrease apolipoprotein M expression.
Inflammation can produce abnormalities that could increase the risk for atherosclerosis including alterations in lipid and lipoprotein metabolism. Apolipoprotein M is a recently described HDL-associated apoprotein expressed mainly in the liver and kidney with protective effects against atherosclerosis. In this study, we describe the regulation of apolipoprotein M during the acute phase response. Stimuli that produce systemic inflammation, LPS, zymosan, or turpentine, decrease apolipoprotein M mRNA levels in the liver and kidney. Treatment of Hep3B hepatoma cells with TNF or IL-1 also decreased apolipoprotein M mRNA levels. The decrease in apolipoprotein M mRNA leads to a decrease in apolipoprotein M secretion into the media in Hep3B cells and a decrease in mouse serum following LPS administration. Moreover, in humans with acute bacterial infections or chronic HIV infection, serum apolipoprotein M levels are decreased. Apolipoprotein M is a negative acute response protein that decreases during infection and inflammation. These results are consistent with the finding that infections and inflammatory disorders accompanied by systemic inflammation are associated with an increased risk of atherosclerosis.
Department of Veterans Affairs Medical Center, Metabolism Section, SFVAMC, San Francisco, CA 94121, United States. kenneth.feingold@ucsf.edu
Kenneth R
KR
Feingold
Judy K
JK
Shigenaga
Lisa G
LG
Chui
Arthur
A
Moser
Weerapan
W
Khovidhunkit
Carl
C
Grunfeld
D000210:Acute-Phase Reaction / Q000276:immunology* / Q000378:metabolism; D000818:Animals; D001053:Apolipoproteins / Q000097:blood / Q000235:genetics / Q000276:immunology*; D000075243:Apolipoproteins M; D050197:Atherosclerosis / Q000276:immunology* / Q000378:metabolism / Q000503:physiopathology; D006528:Carcinoma, Hepatocellular; D045744:Cell Line, Tumor; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000276:immunology / Q000378:metabolism / Q000503:physiopathology; D015658:HIV Infections / Q000276:immunology / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D054834:Lipocalins; D008070:Lipopolysaccharides / Q000494:pharmacology; D008113:Liver Neoplasms; D051379:Mice; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000378:metabolism; D018805:Sepsis / Q000276:immunology* / Q000378:metabolism / Q000503:physiopathology; D014657:Vasculitis / Q000276:immunology* / Q000378:metabolism / Q000503:physiopathology
C400523:APOM protein, human; C501623:ApoM protein, mouse; D001053:Apolipoproteins; D000075243:Apolipoproteins M; D054834:Lipocalins; D008070:Lipopolysaccharides; D012333:RNA, Messenger; C082161:lipopolysaccharide A