Exosome-LncPICALM-AU1 regulates endothelial–mesenchymal transition in hepatopulmonary syndrome

As important mediators of intercellular communication, exosome have can modulate various cellular functions by transferring a variety of intracellular components to target cells. However, little is known about the role of exosome-mediated communication between distant organs. Hepatopulmonary syndrome (HPS) is a severe lung injury caused by chronic liver disease. A new long noncoding RNA (lncRNA) PICALM-AU1 was found and upregulated in the liver of HPS. It was located in the cholangiocytes of liver and then, secreted as exosome into the serum. PICALM-AU1 carrying serum exosomes induced endothelial-mesenchymal transition (EndMT) of PMVECs and promoted lung injury in vivo and in vitro. Furthermore, overexpression of PICALM-AU1 significantly suppressed miR144-3p and subsequently induced ZEB1 expression. Taken together, our findings identified cholangiocyte-derived exosomal lncRNA PICALM-AU1 plays a critical role in the EndMT of HPS lung. And PICALM-AU1 represents a noninvasive biomarker and potential therapeutic target for HPS.