Dataset Information

Antagonizing circRNA_002581-miR-122-CPEB1 axis alleviates NASH through restoring PTEN-AMPK-mTOR pathway regulated autophagy.

ABSTRACT: Circular RNAs (circRNAs) have been shown to play critical roles in cancer biology, but their functions in nonalcoholic steatohepatitis (NASH) remain unexplored. Full length of circRNA_002581 was amplified and sequenced, followed by RNA immunoprecipitation, RNA-Fluorescence in Situ Hybridization and dual luciferase reporter gene analysis to confirm the existence of the circRNA_002581-miR-122-CPEB1 regulatory axis in vitro. CircRNA_002581 knockdown was used to study its roles in high concentration of free fatty acids-induced NASH-like cell model and a methionine and choline deficiency (MCD) diet-induced NASH mice model. Autophagy flux and related potential PTEN-AMPK-mTOR pathway were tested by western blot. CircRNA_002581 overexpression significantly relieved the inhibitory role of miR-122 on its target CPEB1 by sponging miR-122. CircRNA_002581 knockdown markedly attenuated lipid droplet accumulation, reduced the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), pro-inflammatory cytokines, apoptosis, H₂O₂, and increased ATP level in both mice and cellular models of NASH. Mechanistically, circRNA_002581 interference significantly rescue the defective autophagy evidenced by increased autophagosome number, upregulated LC3-II/I level, and decreased p62 level. Further chloroquine-mediated total autophagy inhibition antagonizes the protective effect of circRNA_002581 knockdown. Finally, CPEB1-PTEN-AMPK-mTOR pathway is shown to link the autophagy and circRNA_002581 knockdown-mediated NASH alleviation. CircRNA_002581-miR-122-CPEB1 axis actively participates in the pathogenesis of NASH through PTEN-AMPK-mTOR pathway-related autophagy suppression. Targeting circRNA_002581 is a potential therapeutic strategy for NASH through partial autophagy restoration.

SUBMITTER: Jin X

PROVIDER: S-EPMC7018772 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Antagonizing circRNA_002581-miR-122-CPEB1 axis alleviates NASH through restoring PTEN-AMPK-mTOR pathway regulated autophagy.

Jin Xi X Gao Jianguo J Zheng Ruoheng R Yu Mosang M Ren Yue Y Yan Tianlian T Huang Yue Y Li Youming Y

Cell death & disease 20200213 2

Circular RNAs (circRNAs) have been shown to play critical roles in cancer biology, but their functions in nonalcoholic steatohepatitis (NASH) remain unexplored. Full length of circRNA_002581 was amplified and sequenced, followed by RNA immunoprecipitation, RNA-Fluorescence in Situ Hybridization and dual luciferase reporter gene analysis to confirm the existence of the circRNA_002581-miR-122-CPEB1 regulatory axis in vitro. CircRNA_002581 knockdown was used to study its roles in high concentration ...[more]

PMID: 32054840

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Dataset Information

Antagonizing circRNA_002581-miR-122-CPEB1 axis alleviates NASH through restoring PTEN-AMPK-mTOR pathway regulated autophagy.

Publications

Antagonizing circRNA_002581-miR-122-CPEB1 axis alleviates NASH through restoring PTEN-AMPK-mTOR pathway regulated autophagy.

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