Microfluidics-based Study On The Repair Of Damaged Cardiomyocytes By Skeletal Myoblasts

Myocardial infarction (MI) is a major cause of mortality worldwide with a steadyincrease in prevalence. There is currently no available cure beyond orthotopic hearttransplantation, which for a number of reasons is an option only for a small fraction of allpatients. Considerable hope has therefore been placed on the possibility of treating a failingheart by replacing lost cardiomyocytes, either through transplantation of various types ofstem cells or by boosting endog-enous regenerative mechanisms in the heart.In the present study, we presented an integrated microfluidic device that could mimiccell engraftment as an adjunct to Coronary artery bypass grafting (CABG) to investigateskeletal myoblast engraftment to treat myocardial after chemical injury. The microfluidicchip is constituted by five identical structural units, and each structural unit can be culturedrat cardiac H9c2cells and rat skeletal myoblastsL6. Using the control with microchannelsand microvalve, rat cardiac H9c2cells and rat skeletal myoblastsL6can culture in the cellchambers respectively. Seeding and positioning after12hours, two types of cells exhibitedpositive adhesion and proliferation. The viability of the cells is measured by AO/PI doublestaining and is as high as viability (H9c2cells:99.5%; L6cells:99.1%) in the chamber.For the initial analysis of on-chip H9C2injury, the FCCP concentration and treatment timewere chosen based on the conventional MTT and AO-PI double-staining assays. Therefore,FCCP (30μmol/L) was chosen in this study to produce in situ a spatially controllablehypoxia condition. FCCP (30μmol/L) treat myocardial cells in the middle culture chamberfor30mins, and the model of myocardial cells in hypoxic injury is established successfully.Then, these control valves are opened after myocardial hypoxia, and Mediums of Myoblastsand cardiomyocytes communicate with each other. Myoblast cells not only migrate in thecardiomyocytes chamber, but also provide Mediums nutrients for cardiac myocytes. Twotypes of cells contact co-culture after12h, the myocardial cells have a significant restorationchanges in cell size, roundness, actin, nuclear and mitochondrial membrane potential after30hours. The study lay the theoretical foundation for the application of the microfluidicchip in MI study and provide new ideas for the occurrence of acute myocardial infarction (AMI) and therapeutic mechanism.