Human chemically derived hepatic progenitors (hCdHs) reprogrammed using three chemicals—HGF, A83-01, and CHIR99021 (collectively denoted as “HAC”)—have been suggested as a novel therapeutic for patients with severe liver diseases in our previous study. Despite its high proliferation and re-differentiation ability into functional hepatocytes, the reprogramming mechanism of hCdHs remained unknown. Recently, it has been reported that autophagy, a self-degradation process, is responsible for stem cell metabolism. In this study, we investigated whether autophagy regulates the generation mechanism of CdHs, mainly using hepatocytes from C57BL/6 mice, with additional analysis using human hepatocytes. As a result, we found that autophagy flux is inhibited during the generation of mouse CdHs (mCdHs) by A83-01, which is compensated by CHIR99021. Moreover, the suppression of autophagy by bafilomycin A1 enhanced the proliferation ability of mCdHs during the generation process. hCdHs also showed a similar autophagy inhibition pattern to mCdHs during the generation process. Taken together, our study indicates that autophagy is downregulated during the generation of CdHs, promoting their proliferation. This may contribute to the production of hCdHs with stable productivity, which may serve as a therapeutic for severe liver diseases.

Purpose: Over the past decade, interest in exosomes as therapeutics has surged. In particular, stem-cell–derived exosomes may be more effective as a treatment for liver disease than the stem cells themselves. We have previously developed human chemically derived hepatic progenitors (hCdHs) from human hepatocytes. hCdHs can differentiate into hepatocytes and cholangiocytes, regenerating the liver in mouse models. In this study, we evaluated the mitigating effects of hCdHs-derived exosomes (hCdHs-exo) on liver damage and compared them with those of exosomes from bone marrow mesenchymal stem cells (BMMSCs-exo). Methods: Exosomes were isolated from hCdHs and BMMSCs by culturing cells in large quantities and separating the exosomes from the culture medium using ultracentrifugation. Isolated exosomes were characterized by various methods before experimental use. In vitro, the ability of exosomes to inhibit activation of hepatic stellate cells (HSCs) by transforming growth factor beta 1 was evaluated. In vivo, exosomes were injected into mice with carbon tetrachloride (CCl4 )-induced liver damage, and their effectiveness in mitigating liver damage was assessed by histological staining and biochemical analysis. Results: The analyses confirmed the successful isolation of exosomes from both cell types. In vitro, hCdHs-exo significantly reduced the levels of transcription factors and activation markers in induced HSCs. In vivo, hCdHs-exo effectively alleviated liver damage caused by CCl4 . Furthermore, both in vitro and in vivo studies confirmed that hCdHs-exo had a greater effect in alleviating liver damage than did BMMSCs-exo. Conclusion These results demonstrate that hCdHs-exo, similarly to hCdHs, have superior efficacy in alleviating liver damage compared with BMMSCs-exo.

Purpose: Over the past decade, interest in exosomes as therapeutics has surged. In particular, stem-cell–derived exosomes may be more effective as a treatment for liver disease than the stem cells themselves. We have previously developed human chemically derived hepatic progenitors (hCdHs) from human hepatocytes. hCdHs can differentiate into hepatocytes and cholangiocytes, regenerating the liver in mouse models. In this study, we evaluated the mitigating effects of hCdHs-derived exosomes (hCdHs-exo) on liver damage and compared them with those of exosomes from bone marrow mesenchymal stem cells (BMMSCs-exo). Methods: Exosomes were isolated from hCdHs and BMMSCs by culturing cells in large quantities and separating the exosomes from the culture medium using ultracentrifugation. Isolated exosomes were characterized by various methods before experimental use. In vitro, the ability of exosomes to inhibit activation of hepatic stellate cells (HSCs) by transforming growth factor beta 1 was evaluated. In vivo, exosomes were injected into mice with carbon tetrachloride (CCl4 )-induced liver damage, and their effectiveness in mitigating liver damage was assessed by histological staining and biochemical analysis. Results: The analyses confirmed the successful isolation of exosomes from both cell types. In vitro, hCdHs-exo significantly reduced the levels of transcription factors and activation markers in induced HSCs. In vivo, hCdHs-exo effectively alleviated liver damage caused by CCl4 . Furthermore, both in vitro and in vivo studies confirmed that hCdHs-exo had a greater effect in alleviating liver damage than did BMMSCs-exo. Conclusion These results demonstrate that hCdHs-exo, similarly to hCdHs, have superior efficacy in alleviating liver damage compared with BMMSCs-exo.

Purpose: Over the past decade, interest in exosomes as therapeutics has surged. In particular, stem-cell–derived exosomes may be more effective as a treatment for liver disease than the stem cells themselves. We have previously developed human chemically derived hepatic progenitors (hCdHs) from human hepatocytes. hCdHs can differentiate into hepatocytes and cholangiocytes, regenerating the liver in mouse models. In this study, we evaluated the mitigating effects of hCdHs-derived exosomes (hCdHs-exo) on liver damage and compared them with those of exosomes from bone marrow mesenchymal stem cells (BMMSCs-exo). Methods: Exosomes were isolated from hCdHs and BMMSCs by culturing cells in large quantities and separating the exosomes from the culture medium using ultracentrifugation. Isolated exosomes were characterized by various methods before experimental use. In vitro, the ability of exosomes to inhibit activation of hepatic stellate cells (HSCs) by transforming growth factor beta 1 was evaluated. In vivo, exosomes were injected into mice with carbon tetrachloride (CCl4 )-induced liver damage, and their effectiveness in mitigating liver damage was assessed by histological staining and biochemical analysis. Results: The analyses confirmed the successful isolation of exosomes from both cell types. In vitro, hCdHs-exo significantly reduced the levels of transcription factors and activation markers in induced HSCs. In vivo, hCdHs-exo effectively alleviated liver damage caused by CCl4 . Furthermore, both in vitro and in vivo studies confirmed that hCdHs-exo had a greater effect in alleviating liver damage than did BMMSCs-exo. Conclusion These results demonstrate that hCdHs-exo, similarly to hCdHs, have superior efficacy in alleviating liver damage compared with BMMSCs-exo.