Sepideh Alinezhad-Bermi1,2, Hana Hanaee Ahvaz2, Shiva Irani1 and Mahboubeh Kabiri3
1Islamic Azad University, Iran 2Shahid Beheshti University of Medical Sciences, Iran 3University of Tehran, Iran
Posters-Accepted Abstracts: J Biotechnol Biomater
Due to limited blood supply, cartilage has an inadequate repair post injury. Despite the advantage of autologous chondrocytes implantation, this strategy suffers from donor site morbidity and inadequate cell supply. Chondrogenic differentiation of mesenchymal stem cells (MSC) can be used instead to overcome such limitations. Among the reported chondrogenic conditions, application of high osmolarity has been used increasingly to enhance chondrogenic differentiation potential through mimicking the osmotic character of the normal tissue. The osmolarity of the normal cartilage tissue is significantly higher than that of other tissues. For that reason, increased osmolarity is considered as a cue for further improving chondrogenic differentiation yield. On the other hand, high osmolarity is one of the key regulators of angiogenesis induction. As angiogenesis in cartilage is an important index of the cartilage related diseases monitoring the possible angiogenic potential of hypertension on chondrogenic differentiation is of profound importance. Therefore, the aim of this study was to investigate the angiogenic effects of osmolarity on adipose derived MSC chondrogenesis. MSCs were differentiated under different hyperosmotic conditions using NaCl. The angiogenesis induction potential was evaluated by measuring the VEGF secretion and VEGFR2 activation using ELISA and western blot techniques respectively. The effect of hyper-osmolarity on MSC growth and proliferation was evaluated by MTT assay. Changes in gene expression levels for cartilage specific markers (Collagen II, Aggrecan, Versican and Sox9) were determined by real time PCR. Also chondrogenesis was assessed by measuring secreted glycosaminoglycan in the medium or that kept in cell ECM. The results will determine the possible effect of high osmolarity on angiogenesis and therefore be illustrative for wise application of appropriate osmolarity in chondrogenesis differentiation.