Effect of Insulin on Umbilical Cordʹʹs Mesenchymal Stem Cells on PLLA Polymer Scaffold

Tissue engineering started a new field of study which has made great view in renewal, repairing and keeping the function of different tissue especially bone tissue, by the use of cells, scaffold and biomolecules. Nano scaffold of PLLA polymer is made by means of electro-spinning method. Nanoscaffold was examined for surface feature, biodegradability, percentage of porosities and Size of pores. To prove the stem cell character of detached cells from venous tissue, cells were examined by flowcytometry for cell makers by which they were positive on CD90, CD105 and negative CD45 marker. Humane mesenchymal stem cells were cultured on PLLA nano scaffold. Nano scaffold having these cells, where treated with bone differentiation medium for 21 days and some samples were treated with different dosage of insulin. On day 21 alizarin red and von kossa staining was performed for treated cells. Observation of cells after getting stained, showed the precipitation of calcium in extra cellular matrix .The nano scaffold having differentiated cells spread black in von kossa and red in alizarin red Because of calcium precipitates. Differentiating to bone in high concentration was hardly seen in samples containing different insulin dosages and low glucose.SEM supported the calcium precipitation in nano scaffolds having cells differentiated to bone tissue. Observations of SEM showed that lower insulin concentration has better effect on differentiation of bone cells. According to gained results, concentration as 4IU of insulin suggested as proper concentration for bone cells differentiation on PLLA nano scaffolds.