CircRNA608-microRNA222-PINK1 axis regulates the mitophagy of hepatic stellate cells in NASH related fibrosis

Zi-Xin Xu; Jing-Ze Li; Qin Li; Ming-Yi Xu; Hui-Yi Li

doi:10.1016/j.bbrc.2022.04.008

CircRNA608-microRNA222-PINK1 axis regulates the mitophagy of hepatic stellate cells in NASH related fibrosis

Biochem Biophys Res Commun. 2022 Jun 25:610:35-42. doi: 10.1016/j.bbrc.2022.04.008. Epub 2022 Apr 5.

Authors

Zi-Xin Xu¹, Jing-Ze Li², Qin Li², Ming-Yi Xu³, Hui-Yi Li⁴

Affiliations

¹ Department of Gastroenterology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China; Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China.
² Department of Gastroenterology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China.
³ Department of Gastroenterology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China. Electronic address: xumingyi@tongji.edu.cn.
⁴ Department of Gastroenterology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China. Electronic address: lhy177279@163.com.

PMID: 35436629
DOI: 10.1016/j.bbrc.2022.04.008

Abstract

Background: Increasing evidences have confirmed the relationship between mitophagy and nonalcoholic steatohepatitis (NASH). The exact mechanism of upstream circular RNAs (circRNAs) regulating PTEN-induced putative kinase 1 (PINK1) mediated mitophagy and its contribution to NASH-related liver fibrosis was explored in our study.

Methods: Primary hepatic stellate cells (PHSCs) from C57BL/6 mice transfected with small interfering RNAs against PINK1 (si-PINK1) and negative control (si-NC) were prepared to perform circRNA sequence. Differentially expressed circRNAs, bioinformatic analysis and predicting software were performed to select axis of circ608/miR-222/PINK1. The expressions of circ608/miR-222/PINK1 were verified by RT-qPCR. The mitochondrial function was evaluated by immunofluorescence staining of COX4 and LC3B.

Results: PINK1-mediated mitophagy was inhibited in NASH-related liver fibrosis mice. CircRNA sequence revealed there were 37 DE-circRNAs between si-PINK1 PHSCs and si-NC PHSCs. Bioinformatic analysis showed these DE-circRNAs were related to enriched signaling pathways (such as Wnt, Rap1, mTOR, Hippo) regulating liver fibrosis and mitophagy. Circ608 was significantly down-regulated in lipotoxic HSCs and in livers of NASH-related liver fibrosis mice. MiR222 was identified to be the target miRNA of circ608 and was negatively regulated by circ608 in lipotoxic HSCs. MiR222 also had a binding site with PINK1 and could negatively regulate PINK1. So, the axis of circ608-miR222-PINK1 was proved to participate in NASH-related liver fibrosis by regulating mitophagy. These results illustrated that circ608 might promote PINK1-mediated mitophagy though inhibiting miR222 in lipotoxic HSCs.

Conclusion: Circ608 could promote PINK1-mediated mitophagy of HSCs though inhibiting miR222 in NASH-related liver fibrosis.

Keywords: Circular RNA (circRNA); Hepatic stellate cells (HSCs); Liver fibrosis; Mitophagy; Nonalcoholic steatohepatitis (NASH); PTEN-induced putative kinase 1 (PINK1).

MeSH terms

Animals
Fibrosis
Hepatic Stellate Cells / metabolism
Liver Cirrhosis / metabolism
Mice
Mice, Inbred C57BL
MicroRNAs* / genetics
Mitophagy / genetics
Non-alcoholic Fatty Liver Disease* / metabolism
Protein Kinases* / genetics
RNA, Circular* / genetics

Substances

MIRN222 microRNA, mouse
MicroRNAs
RNA, Circular
Protein Kinases
PTEN-induced putative kinase