Differentiation of bone marrow mesenchymal stem cells into chondrocyte-like cells under the conditions of transforming growth factor beta and cyclical tensile strain / 中国组织工程研究

ABSTRACT

BACKGROUND:Transforming growth factor-βhas been shown to exert an obvious induction effect on the differentiation of bone marrow mesenchymal stem cells into chondrocytes. Cyclical tensile strain simulates mechanical environment of chondrocytes in the body, and plays an important regulatory role in cellproliferation and differentiation. OBJECTIVE:To discuss the synergy of transforming growth factor-βand cyclical tensile strain in inducing the differentiation of bone marrow mesenchymal stem cells into chondrocyte-like cells. METHODS:A total of 10 2-month-old New Zealand rabbits were selected. Bone needle was used to penetrate the medul ary cavity of bone. 3.0-4.0 mL of bone marrow was extracted for isolation and culture of bone marrow mesenchymal stem cells. Passage 3 cells were randomly assigned to four groups:blank, transforming growth factor-β, cyclical tensile strain and cyclical tensile strain+transforming growth factor-βgroups. After 1, 3 and 6 days, cells were obtained. General morphology was observed using safranin O staining. Glycosaminoglycan levels were detected by alcian blue staining. Matrix metal oproteinase-13 and tissue inhibitor of metal oproteinase-1 levels in supernatant were measured using ELISA. Type II col agen, matrix metal oproteinase-13 and tissue inhibitor of metal oproteinase-1 mRNA relative expression was detected using RT-PCR. RESULTS AND CONCLUSION:Safranin O staining showed fusiform or irregular triangular cells. cellnumber and matrix secretion increased in each experimental group than in blank group. Glycosaminoglycan levels in the supernatant were greater in the transforming growth factor-βand cyclical tensile strain+transforming growth factor-βgroups than in the blank group (P<0.05). Type II col agen mRNA relative expression was higher in the cyclical tensile strain+transforming growth factor-βgroup than in the blank group (P<0.05). Results indicated that transforming growth factor-βand cyclical tensile strain could induce the differentiation of bone marrow mesenchymal stem cells into chondrocytes, showing an apparent cooperative action.