Exosomes derived from induced cardiopulmonary progenitor cells alleviate acute lung injury in mice.

Cardiopulmonary progenitor cells (CPPs) constitute a minor subpopulation of cells that are commonly associated with heart and lung morphogenesis during embryonic development but completely subside after birth. This fact offers the possibility for the treatment of pulmonary heart disease (PHD), in which the lung and heart are both damaged. A reliable source of CPPs is urgently needed. In this study, we reprogrammed human cardiac fibroblasts (HCFs) into CPP-like cells (or induced CPPs, iCPPs) and evaluated the therapeutic potential of iCPP-derived exosomes for acute lung injury (ALI). iCPPs were created in passage 3 primary HCFs by overexpressing GLI1, WNT2, ISL1 and TBX5 (GWIT). Exosomes were isolated from the culture medium of passage 6-8 GWIT-iCPPs. A mouse ALI model was established by intratracheal instillation of LPS. Four hours after LPS instillation, ALI mice were treated with GWIT-iCPP-derived exosomes (5 × 109, 5 × 1010 particles/mL) via intratracheal instillation. We showed that GWIT-iCPPs could differentiate into cell lineages, such as cardiomyocyte-like cells, endothelial cells, smooth muscle cells and alveolar epithelial cells, in vitro. Transcription analysis revealed that GWIT-iCPPs have potential for heart and lung development. Intratracheal instillation of iCPP-derived exosomes dose-dependently alleviated LPS-induced ALI in mice by attenuating lung inflammation, promoting endothelial function and restoring capillary endothelial cells and the epithelial cells barrier. This study provides a potential new method for the prevention and treatment of cardiopulmonary injury, especially lung injury, and provides a new cell model for drug screening.

Cardiopulmonary progenitors facilitate cardiac repair via exosomal transfer of miR-27b-3p targeting the SIK1-CREB1 axis.

Ischemic heart disease, especially myocardial infarction (MI), is one of the leading causes of death worldwide, and desperately needs effective treatments, such as cell therapy. Cardiopulmonary progenitors (CPPs) are stem cells for both heart and lung, but their repairing role in damaged heart is still unknown. Here, we obtained CPPs from E9.5 mouse embryos, maintained their stemness while expanding, and identified their characteristics by scRNA-seq, flow cytometry, quantitative reverse transcription-polymerase chain reaction, and differentiation assays. Moreover, we employed mouse MI model to investigate whether CPPs could repair the injured heart. Our data identified that CPPs exhibit hybrid fibroblastic, endothelial, and mesenchymal state, and they could differentiate into cell lineages within the cardiopulmonary system. Moreover, intramyocardial injection of CPPs improves cardiac function through CPPs exosomes (CPPs-Exo) by promotion of cardiomyocytic proliferation and vascularization. To uncover the underlying mechanism, we used miRNA-seq, bulk RNA-seq, and bioinformatic approaches, and found the highly expressed miR-27b-3p in CPPs-Exo and its target gene Sik1, which can influence the transcriptional activity of CREB1. Therefore, we postulate that CPPs facilitate cardiac repair partially through the SIK1-CREB1 axis via exosomal miR-27b-3p. Our study offers a novel insight into the role of CPPs-Exo in heart repair and highlights the potential of CPPs-Exo as a promising therapeutic strategy for MI.

Changes in synaptic plasticity and expression of glutamate receptor subunits in the CA1 and CA3 areas of the hippocampus after transient global ischemia.

Excess glutamate release from the presynaptic membrane has been thought to be the major cause of ischemic neuronal death. Although both CA1 and CA3 pyramidal neurons receive presynaptic glutamate input, transient cerebral ischemia induces CA1 neurons to die while CA3 neurons remain relatively intact. This suggests that changes in the properties of pyramidal cells may be the main cause related to ischemic neuronal death. Our previous studies have shown that the densities of dendritic spines and asymmetric synapses in the CA1 area are increased at 12h and 24h after ischemia. In the present study, we investigated changes in synaptic structures in the CA3 area and compared the expression of glutamate receptors in the CA1 and CA3 hippocampal regions of rats after ischemia. Our results demonstrated that the NR2B/NR2A ratio became larger after ischemia although the expression of both the NR2B subunit (activation of apoptotic pathway) and NR2A subunit (activation of survival pathway) decreased in the CA1 area from 6h to 48h after reperfusion. Furthermore, expression of the GluR2 subunit (calcium impermeable) of the AMPA receptor class significantly decreased while the GluR1 subunit (calcium permeable) remained unchanged at the same examined reperfusion times, which subsequently caused an increase in the GluR1/GluR2 ratio. Despite these notable differences in subunit expression, there were no obvious changes in the density of synapses or expression of NMDAR and AMPAR subunits in the CA3 area after ischemia. These results suggest that delayed CA1 neuronal death may be related to the dramatic fluctuation in the synaptic structure and relative upregulation of NR2B and GluR1 subunits induced by transient global ischemia.