Gene expression changes under cyclic mechanical stretch in rat retinal Muller cells

The retina is often subjected to tractional forces in a variety of conditions, for instance, pathological myopia, proliferative vitreoretinopathy. As the predominant glial element in the sensory retina, Muller cells are responsible for the homeostatic and metabolic support of retinal neurons and active players in virtually all forms of retinal injury and disease. Besides, Muller cells span the entire retinal thickness, extending from the inner to the outer limiting membranes, with cell bodies located in the inner nuclear layer and lateral processes expanding into the plexiform layers of the tissue. Because of this unique morphology, Muller cells can sense even minute changes in the retinal structure because of the mechanical stretching of their long processes or side branches. Thus, it’s reasonable to infer that Muller cells also participate in ocular diseases when the retina is overstretched. In this study, we aim to investigate the whole genome regulation of Muller cells under mechanical stretching, which may help in excluding possible molecular mechanisms that would account for many retinal diseases in which the retina is often subjected to mechanical forces. We used microarrays to identify patterns of gene expression changes induced by cyclic mechanical stretching in Muller cells. Rat Muller cells were seeded onto flexible bottom culture plates and subjected to a cyclic stretching regimen of 15% equibiaxial stretching for 1 and 24 h.Muller cells cultured under the same conditions but with no applied mechanical strain were considered as the unstretched control. At each time points (1 and 24 h), three totally independent experiments (3 stretched samples and 3 control samples) were conducted. Muller cells were selected for RNA extraction and hybridization on Affymetrix microarrays. Stretch (S); Control (C)