MicroRNAs in the regulation of interfacial behaviors of MSCs cultured on microgrooved surface pattern.

Cell-substrate interaction is one of the most important aspects of tissue engineering. Changes of MSCs interfacial behaviors were found to be triggered by 10 μm wide grooved pattern on poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx). Global marker genes expression and miRNAs profiling analysis provided insights into the regulation network of the topography induced MSCs' cell responses including adhesion, proliferation, differentiation and apoptosis. Compared to MSCs cultured on the smooth substrates, MSCs incubated on microgrooved PHBHHx substrates showed increased expression of osteogenesis-related marker genes including cbfa1, col1a1 and bmp2, and decreased expression of vcl, vinculin encoding gene, adipogenesis-related genes including lpl, des and acta2, as well as myogenesis-related genes of myh11 and nse. The miRNA microarrays revealed that 18 differentially-expressed miRNAs on microgrooved pattern had multiple target genes, contributing comprehensively to the cellular regulation process. Similar to the topography-triggered ostegenenesis, co-transfection of the osteogenic miRNAs combination (miR-140, miR-214, miR-320, miR-351 and miR-674-5p) was able to stimulate the expression of osteogenic marker genes. This study elucidated the important roles of miRNAs in the regulation processes of the microenvironment triggered cell behaviors, and provided clues for the PHA biomedical materials development.