Chondroitin sulfate-D promotes neurite outgrowth by acting as an extracellular ligand for neuronal integrin αVβ3

• Published in: Biochimica et biophysica acta. General subjects Vol. 1863; no. 9; pp. 1319 - 1331
• Main Authors: Shida, Miharu, Mikami, Tadahisa, Tamura, Jun-ichi, Kitagawa, Hiroshi
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2019
• Subjects: binding capacity; central nervous system; Chondroitin sulfate; Chondroitin Sulfates - physiology; extracellular matrix; Focal adhesion kinase; Glycosaminoglycans; Humans; Integrin; Integrin alphaVbeta3 - metabolism; integrins; Ligands; Neurite outgrowth; neurites; Neuronal Outgrowth - drug effects; Neurons - metabolism; non-specific protein-tyrosine kinase; stem cells; GlcA; Glycosaminoglycans; PCAN; NCAN; CNS; GAG; CNTN-1; ECM; GalNAc; GFAP; CS; FAK; PLO; Integrin; PTPRZ1; SPR; PG; Chondroitin sulfate; Focal adhesion kinase; Neurite outgrowth; Ig
• ISSN: 0304-4165; 1872-8006; 1872-8006
• DOI: 10.1016/j.bbagen.2019.06.004

Chondroitin sulfate (CS) chains are prominent extra/pericellular matrix components in the central nervous system (CNS) and can exert positive or negative regulatory effects on neurite outgrowth, depending on the CS structure and the amount. Despite the remarkable abilities of highly sulfated forms of CS chains to enhance neurite outgrowth, the neuronal recognition systems for such promotional CS chains, including CS-D polysaccharide, remain to be fully elucidated. We explored the molecular basis of the CS-D-mediated neurite extension using primary hippocampal neurons cultured on substrate precoated with CS-D polysaccharides, and evaluated functional involvement of a distinct integrin heterodimer as a novel neuronal CS receptor for CS-D. We identified an extracellular matrix receptor, integrin αVβ3, as a functional receptor for CS-D. CS-D, but not CS-C (a precursor form of CS-D) showed significant binding affinity toward recombinant integrin αVβ3 heterodimer and activated intracellular signaling(s) involving focal adhesion kinase (FAK) and Src/Fyn kinase. Functional blockade of the respective players for integrin signaling abrogated the promotional effects of CS-D. We also found the existence of CS-D-induced integrin activation system in neuronal stem/progenitor cell population. The neuronal cell surface integrin αVβ3 can function as a CS receptor for a highly sulfated CS subtype, CS-D. Our findings are the first to demonstrate that CS-dependent neurite outgrowth promotion is exerted via direct activation of specific integrin heterodimers on neuronal cell surfaces, providing new insights into understanding the CS-sensing machineries that regulate CNS development and regeneration. •CS-D-mediated neurite outgrowth is exerted via neuronal cell surface integrin αVβ3.•CS-D is a potent agonist for neuronal integrin αVβ3.•CS-D-induced integrin activation occurs in neuronal stem/progenitor cell system.•Distinct integrin molecules can function as neuroregulatory CS-sensing machineries.