Serum amyloid A1 (SAA1) (SAA1)

Serum amyloid A1 (SAA1) is a major acute-phase protein primarily synthesized in the liver in response to pro-inflammatory cytokines such as IL-1, IL-6, and TNF-alpha (UniProt: P0DJI8). During an acute inflammatory response, its plasma concentration can increase up to 1000-fold, where it associates with high-density lipoprotein (HDL) and influences lipid metabolism and immune cell recruitment (PubMed: 29107071). Chronic elevation of SAA1 is the precursor to AA amyloidosis, a condition where SAA fragments misfold and deposit as insoluble fibrils in organs, particularly the kidneys, leading to organ failure (StatPearls: NBK559232). As a therapeutic target, strategies focus on reducing SAA production through the treatment of underlying inflammatory diseases or by directly inhibiting the formation of amyloid fibrils (PubMed: 32635470). Drugs like colchicine and IL-6 inhibitors (e.g., tocilizumab) are used to lower SAA levels, while agents like eprodisate have been investigated to prevent fibril deposition (ClinicalTrials.gov: NCT00035334). SAA also serves as a sensitive biomarker for monitoring disease activity in various inflammatory and neoplastic conditions (PubMed: 30114604).

Other names

Acute-phase serum amyloid ASAASAA1SAA2Amyloid fibril protein AAPIG4Amyloid protein A

Direct inhibition of SAA fibrillogenesis by competing with glycosaminoglycan binding sites and indirect reduction of SAA hepatic expression through the blockade of upstream pro-inflammatory cytokines like IL-1 and IL-6 (PubMed: 25135445).