Serum Amyloid A Is an Exchangeable Apolipoprotein

Is serum amyloid A an endogenous TLR4 agonist?

Serum amyloid A (SAA), a classical acute-phase protein, is produced predominantly by hepatocytes in response to injury, infection, and inflammation. It has been shown that SAA primes leukocytes and induces the expression and release of proinflammatory cytokines. Here, we report that SAA induces NO production by murine peritoneal macrophages. Using specific inhibitors, we showed that NO producti...

Serum amyloid A protein, apolipoprotein A-I, and apolipoprotein B during the course of acute myocardial infarction.

Serum amyloid A protein (SAA), apolipoprotein A-I (apoA-I), apolipoprotein B (apoB) concentrations, and creatine kinase (CK)-MB isoenzyme activity were serially measured in 10 patients during the course of acute myocardial infarction. Pronounced increases in SAA concentrations were observed in all patients during infarction. The highest SAA values were observed, on average, 67 hours after the o...

Murine apolipoprotein serum amyloid A in solution forms a hexamer containing a central channel.

Serum amyloid A (SAA) is a small apolipoprotein that binds to high-density lipoproteins in the serum. Although SAA seems to play a role in host defense and lipid transport and metabolism, its specific functions have not been defined. Despite the growing implications that SAA plays a role in the pathology of various diseases, a high-resolution structure of SAA is lacking because of limited solub...

Serum Amyloid A Cutting Edge: TLR2 Is a Functional Receptor

Apolipoprotein serum amyloid A down-regulates smooth-muscle cell lipid biosynthesis.

The addition of acute-phase apolipoprotein serum amyloid A (SAA) to cultured aortic smooth-muscle cells caused a decrease in the incorporation of [(14)C]acetate into lipids. Optimal inhibition of lipid biosynthesis was achieved with 2 microM SAA, and the effect was maintained for up to 1 week when SAA was included in the culture medium. Lipid extracts were subjected to TLC and it was determined...