TY - JOUR
T1 - Cyclic strain stimulates proliferative capacity, α2 and α5 integrin, gene marker expression by human articular chondrocytes propagated on flexible silicone membranes
AU - Lahiji, Kian
AU - Polotsky, Anna
AU - Hungerford, David S.
AU - Frondoza, Carmelita G.
N1 - Funding Information:
This work was supported by the Johns Hopkins University Orthopaedic Rheumatology Gift Fund and the Good Sainaritan Hospital, Baltimore, MD.
PY - 2004/5
Y1 - 2004/5
N2 - Chondrocytes comprise less than 10% of cartilage tissue but are responsible for sensing and responding to mechanical stimuli imposed on the joint. However, the effect of mechanical signals at the cellular level is not yet fully defined. The purpose of this study was to test the hypothesis that mechanical stimulation in the form of cyclic strain modulates proliferative capacity and integrin expression of chondrocytes from osteoarthritic knee joints. Chondrocytes isolated from articular cartilage during total knee arthroplasty were propagated on flexible silicone membranes. The cells were subjected to cyclic strain for 24 h using a computer-controlled vacuum device, with replicate samples maintained under static conditions. Our results demonstrated increase in proliferative capacity of the cells subjected to cyclic strain compared with cells maintained under static conditions. The flexed cells also exhibited upregulation of the chondrocytic gene markers type II collagen and aggrecan. In addition, cyclic strain resulted in increased expression of the α2 and α5 integrin subunits, as well as an increased expression of vimentin. There was also intracellular reconfiguration of the enzyme protein kinase C. Our findings suggest that these molecules may play a role in the signal transduction pathway, eliciting cellular response to mechanical stimulation.
AB - Chondrocytes comprise less than 10% of cartilage tissue but are responsible for sensing and responding to mechanical stimuli imposed on the joint. However, the effect of mechanical signals at the cellular level is not yet fully defined. The purpose of this study was to test the hypothesis that mechanical stimulation in the form of cyclic strain modulates proliferative capacity and integrin expression of chondrocytes from osteoarthritic knee joints. Chondrocytes isolated from articular cartilage during total knee arthroplasty were propagated on flexible silicone membranes. The cells were subjected to cyclic strain for 24 h using a computer-controlled vacuum device, with replicate samples maintained under static conditions. Our results demonstrated increase in proliferative capacity of the cells subjected to cyclic strain compared with cells maintained under static conditions. The flexed cells also exhibited upregulation of the chondrocytic gene markers type II collagen and aggrecan. In addition, cyclic strain resulted in increased expression of the α2 and α5 integrin subunits, as well as an increased expression of vimentin. There was also intracellular reconfiguration of the enzyme protein kinase C. Our findings suggest that these molecules may play a role in the signal transduction pathway, eliciting cellular response to mechanical stimulation.
KW - Collagen type II
KW - Extracellular matrix
KW - Mechanical stimulation
KW - Proliferation
KW - Protein kinase C
KW - Vimentin
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U2 - 10.1290/1543-706X(2004)40<138:CSSPCA>2.0.CO;2
DO - 10.1290/1543-706X(2004)40<138:CSSPCA>2.0.CO;2
M3 - Article
C2 - 15479117
AN - SCOPUS:6044224881
SN - 1071-2690
VL - 40
SP - 138
EP - 142
JO - In Vitro Cellular and Developmental Biology - Animal
JF - In Vitro Cellular and Developmental Biology - Animal
IS - 5-6
ER -