Aims: The purpose of the study is to observe the functions of calcium/calmodulin dependent protein kinase II (CaMKII) in the induced chondrogenic differentiation of bone marrow derived mesenchymal stem cells (BMSCs).
Methods: BMSCs was in vitro isolated and cultured for induced chondrogenesis. Western blot was used to ascertain the expression of CaMKII and phosphorylated CaMKII (PCaMKII, activatory CaMKII) in chondrogenic induced BMSCs. MTT method was utilized to observe the impact of CaMKII on the proliferation of BMSCs. The generation of cartilage matrix in BMSCs cells was detected by toluidine blue staining. The levels of cartilage marker genes COL2A1, Aggrecan and SOX9 in BMSCs were gained by real-time fluorescence quantitative polymerase chain reaction (RT-QPCR). Finally, BMSCs proliferation, cartilage matrix generation and the changes of COL2A1, Aggrecan and SOX9 were surveyed after CaMKII being blocked by CaMKII inhibitor KN93.
Results: Expression of CaMKII and PCaMKII could be found in chondrogenic induced BMSCs. CaMKII had no significant influence on BMSCs proliferation, but the toluidine blue staining was obviously lighter, indicating a significant decline in the expression of COL2A1, Aggrecan and SOX9.
Conclusion: As one of the factors influencing the chondrogenic capacity of BMSCs, CaMKII does not impact on BMSCs proliferation, but it can inhibit the chondrogenic ability of BMSCs by influencing its differentiation.
Keywords: CaMKII; bone marrow derived mesenchymal stem cells (BMSCs); chondrogenesis.