Novel design of nano-selenium loaded injectable hydrogel combined with mesenchymal stem cells-derived exosomes improving cardiac repair and nursing care after acute myocardial infarction

Acute myocardial infarction (AMI) has caused cardiac vascular disease to emerge in recent years, and heart failure is the leading cause of death worldwide and modern medicine offers a number of treatments for AMI. In the present investigation, we created a new hydrogel material for the treatment of acute MI repair that combines mesenchymal stem cell (MSCs)-derived exosomes (EX) and selenium nanoparticles (Se NPs)-loaded collagen type 1 (COL-I)/tannic acid (TA) hydrogel. The physico-chemical characterizations of prepared Se NPs were systematically analysed by efficient analytical and spectroscopic methods. In vitro cytocompatibility analyses, established that prepared hydrogel samples have greater cell viability by MTT and LDH assays, which described that the suitability of hydrogel for the AMI treatment. In vitro cell migration assay exhibited that ∼95% of cell migration ability for Se-EX/Hydrogel when compared to the other groups on cardiac endothelial cells (cECs). The qRT-PCR analysis revealed that Se-EX/Hydrogel provided 3-fold decreasing of pro-inflammatory factors expressions when compared to the LPS induced cell models (cECs and Raw 264.7 cells). In vitro cell apoptosis observations demonstrated that developed Se-EX/Hydrogel effectively reduced the LPS-induced cell apoptosis (13.59 ± 1.2) when compared to the other groups (LPS = 29.51 ± 0.9; LPS + EX = 17.65 ± 1.0; LPS + Se NPs = 18.38 ± 0.8). When blended Se-EX/Hydrogel group were injected into AMI rat models, in vivo observation revealed that improved cardiac function through increased LV wall thickness (2.46 ± 0.6 mm) and significantly reduced infarct size (12.05 ± 1.0%) when compared to the AMI group. The outcome of the results demonstrated that introduced injectable hydrogel had a significant impact on the recovery of infarcted heart.