Research On Calcium Ions On Rat Bone Marrow Mesenchymal Stem Cells Differentiation To Cardiac-like Cells And The Effect Of The Intervention Of Ligustrazine

mesenchymal stem cells(MSCs),besides hematopoietic stem cells,another stem cells existing in bone marrow,could self-replicate,self-renewal and have multilineage differentiation potential.MSCs originate from undifferentiated mesenchymal cells in mesoderm,and are fusiform shape.They could differentiate into various types of connective tissue cells under certain conditions,such as osteocytes,chondrocytes,myocytes,lipocytes and so on.In recent years,MSCs has become focus of investigation due to their application in treatment of cardiovascular diseases,such as myocardial infarction.A large number of experiments showed that MSCs could be induced to differentiate into myocardial-like cells under certain conditions,which could be used to transplant into myocardial infarction area.In the investigations on multilineage differentiation potential of MSCs, the differentiation technology in vitro and in vivo of MSCs into bone tissue, cartilage tissue,and fat tissue,etc.has been mature,even has been admitted measure to culture and identify MSCs.But there were not many investigations on cardiac muscle cells oriented differentiation of MSCs to the myocardial cells in vitro and effect of micro-environment on the differentiation.Objective:This investigation aimed to study the mechanism of calcium ions and the intervention effect of tetramethylpyrazine during the course of differentiation of MSCs into myocardial-like cells.Methods:We added 5-azacytidine,myocardial cell culture supernatant and hypoxia-ischemia reoxygenation myocardial oxygen cell supernatant into MSCs culture system,and simulated cardiac micro-environment in vitro,to study the mechanism of calcium ions and the role of tetramethylpyrazine during the course of differentiation of MSCs to cardiomyocyte-like cells under different myocardial micro-environment.Results:1.we successfully established standardized experimental techniques of isolated culturing,identifying,purifying and amplifying MSCs in SD rats; P5-generation MSCs growth in good condition and maintained undifferentiated state,and could be the cells source of follow-up experiments.2.Successfully established myocardial isolated culture method and modeling method of hypoxic-ischemic myocardial cells in SD neonatal rat.3.Calcium ions,as the second messenger,played an important role in the course of differentiation of MSCs into myocardial-like cells,and were related to the degree of differentiation of MSCs in a certain extent.It was uncertain of the role of extracellular calcium influx and intracellular calcium release in the course of differentiation of MSCs into myocardial-like cells,and it still needed further investigation.4.Tetramethylpyrazine,as a traditional medicine monomer with cardioprotective function,was used for clinical treatment of cardiovascular diseases,and played an important role in the differentiation of MSCs into myocardial-like cells.There has been no report on tetramethylpyrazine used in the differentiation of MSCs.We found that tetramethylpyrazine,especially high dose of tetramethylpyrazine,as the calcium channel blocker,could enhance the concentration of intracellular calcium ion,suggesting that the mechanism of tetramethylpyrazine in the differentiation of MSCs was complex,rather than simple blocking extracellular calcium influx,which is worth more in-depth research.conclusion:To sum up,this investigation explored and investigated simulating myocardial micro-environment in vitro to induce myocardial MSCs into myocardial-like cells,studied the mechanism of calcium ions and the great role of tetramethylpyrazine in the process of differentiation of MSCs,and supplied theoretical basis and experimental evidences for application of MSCs transplantation in the treatment of cardiovascular diseases and follow-up relevant animal experiments in vitro.