effects of combined cyclic-static stretch on orientation and proliferation of human mesenchymal stem cells

objective: cell vital function has correlation with mechanical loadings that cell experiences. here, effects of in-vitro combined cyclic-static stretch on proliferation of human mesenchymal stem cell (hmsc) were evaluated. materials and methods: hmscs were cultured on gelatin coated elastic membranes, and exposed to stretch loading. four different regimes of cyclic, static, combined cyclic-static, and cyclic with a period of unloading were exerted on the elastic membrane. duration of cyclic loading and static loading was 5 and 12 hours respectively. results: the results illustrate that 10% cyclic stretch causes cell alignment but there were no significant proliferation differences between control and test group. combined cyclic-static stretch reduced proliferation significantly while cyclic stretch with an unloading period increased cell proliferation significantly. at last, static stretch did not affect cell proliferation significantly. conclusion: cell stretching regimes and post-loading duration are effective factors on cell proliferation.