Combined stimulation with cyclic stretching and hypoxia increases production of matrix metalloproteinase-9 and cytokines by macrophages

► Stretch under hypoxia increases macrophage production of matrix metalloproteinase-9. ► Stretch enhances macrophage releases of interleukin-8 and tumor necrosis factor-α. ► Macrophage conditioned medium induces smooth muscle cell apoptosis under 10% stretch.