biglycan

**Biglycan** is a small leucine-rich repeat proteoglycan (SLRP) found in the extracellular matrix (ECM) of tissues including bone, cartilage, tendon, and muscle. Proteolytically released soluble biglycan acts as a damage-associated molecular pattern (DAMP), binding Toll-like receptors **TLR2** and **TLR4** on macrophages to activate MAPK (p38, ERK) and NF-κB pathways, inducing TNF-α, MIP-2, and NLRP3 inflammasome activation for IL-1β secretion, thereby triggering sterile inflammation and amplifying responses to pathogens. It also interacts with BMPs (e.g., BMP2/4/6) and Wnt/β-catenin signaling to promote osteoblast differentiation and bone formation, binds dystroglycan and MuSK to stabilize the dystrophin-glycoprotein complex and neuromuscular synapses in muscular dystrophies, and contributes to tissue repair, fibrosis, and vascular smooth muscle proliferation.[1][7][4]

Other names

PG-Iproteoglycan-IBGN