title: Softening Substrates Promote Chondrocytes Phenotype via RhoA/ROCK Pathway.
abstract: Due to its evascular, aneural, and alymphatic conditions, articular cartilage shows extremely poor regenerative ability. Thus, directing chondrocyte toward a desired location and function by utilizing the mechanical cues of biomaterials is a promising approach for effective tissue regeneration. However, chondrocytes cultured on Petri dish will lose their typical phenotype which may lead to compromised results. Therefore, we fabricated polydimethylsiloxane (PDMS) materials with various stiffness as culture substrates. Cell morphology and focal adhesion of chondrocytes displayed significant changes. The cytoskeletal tension of the adherent cells observed by average myosin IIA fluorescent intensity increased as stiffness of the underlying substrates decreased, consistent with the alteration of chondrocyte phenotype in our study. Immunofluorescent images and q-PCR results revealed that chondrocyte cultured on soft substrates showed better chondrocyte functionalization by more type II collagen and aggrecan expression, related to the lowest mRNA level of Rac-1, RhoA, ROCK-1, and ROCK-2. Taken together, this work not only points out that matrix elasticity can regulate chondrocyte functionalization via RhoA/ROCK pathway, but also provides new prospect for biomechanical control of cell behavior in cell-based cartilage regeneration.
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University , Chengdu 610041, P.R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University , Chengdu 610041, P.R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Gong
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University , Chengdu 610041, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University , Chengdu 610041, P.R. China.
authors.forename: Shiyu
authors.initials: S
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University , Chengdu 610041, P.R. China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University , Chengdu 610041, P.R. China.
authors.forename: Tengfei
authors.initials: T
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University , Chengdu 610041, P.R. China.
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Lin
mesh_terms: D053674:Aggrecans; D002358:Cartilage, Articular; D002478:Cells, Cultured; D019902:Chondrocytes; D010641:Phenotype; D015398:Signal Transduction; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein
chemical_list: D053674:Aggrecans; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein
keywords: RhoA/ROCK pathway; chondrocytes; cytoskeleton; elastic substrates; phenotype