Astragaloside IV attenuates macrophage-derived exosomes induced peritoneal fibrosis after inflammatory injury through the miR-204-5p/Foxc1 pathway

Peritoneal dialysis (PD) is a successful renal replacement therapy for end-stage renal disease that effectively improves the quality of life. Long-term PD causes epithelial mesenchymal transformation (MMT) of peritoneal mesothelial cells, leading to peritoneal fibrosis which reduces the efficiency of PD. Macrophages are considered players in the onset and perpetuation of peritoneal injury. Yet, the mechanisms employed by macrophage-mesothelial cells communication to regulate peritoneal fibrosis are not fully elucidated resulting in lack of disease-modified drugs. This study analyzes the role of macrophage-mesothelial cell communication by intraperitoneal injection of macrophage derived exosomes in PD model rats. These results show that macrophages secrete exosomal miR-204-5p that directly targets Foxc1, leading to the activation of MMT in mesothelial cells. The data also shows that intraperitoneal injection of dissolved AS-IV can improve MMT by altering macrophage derived exosomal miRNAs. This study indicates that intercellular crosstalk between peritoneal macrophages and mesothelial cells is mediated by macrophage derived miR-204-5p-containing exosomes that control the MMT progression, providing AS-IV for prevention and treatment of PD induced peritoneal fibrosis. Our results demonstrate, for the first time, a novel role of the AS-IV on miR-204-5p/Foxc1/β-catenin axis in improving peritoneal fibrosis in vivo and vitro. The high-throughput miRNA sequencing from macrophage derived exosomes Exosomes from rat peritoneal macrophage stimulated by Control, LPS or LPS+AS-IV were collected and dissolved in 100ul PBS. Exosomal RNA was extracted for small RNA sequencing analysis.