Related Experiment Video
Updated: Oct 25, 2025
08:37
Assessment of Glutamine as a Fuel Source for Alveolar Macrophages Exposed to Chronic Ethanol Using an Extracellular Flux Bioanalyzer
Published on: November 15, 2024
472
H2O2-mediated autophagy during ethanol metabolism
Cheng Chen1, Shijin Wang1, Linna Yu1
1Center for Alcohol Research and Salem Medical Center, University of Heidelberg, Heidelberg, Germany.
Redox Biology
|August 3, 2021
Summary
Short-term alcohol exposure induces autophagy in liver cells by generating reactive oxygen species (ROS). This contrasts with chronic alcohol consumption, which may suppress autophagy due to protein accumulation.
Area of Science:
- Hepatology
- Cellular Biology
- Biochemistry
Background:
- Alcoholic liver disease (ALD) is a prevalent global health issue with incompletely understood molecular drivers.
- Conflicting data exist regarding the role of autophagy and ethanol-metabolizing enzymes in ALD pathogenesis.
Purpose of the Study:
- To investigate the role of reactive oxygen species (ROS) in mediating autophagy induction by acute ethanol exposure in hepatocytes.
- To elucidate the involvement of ethanol-metabolizing enzymes (CYP2E1) and ROS-generating enzymes (NOX4) in ethanol-induced autophagy.
Main Methods:
- Utilized a mouse model of acute ethanol exposure, immunoblotting, and immunohistochemistry to assess LC3B, CYP2E1, and NOX4 expression.
- Investigated autophagy in primary mouse hepatocytes and Huh7 cells using overexpression and knockdown techniques for CYP2E1 and NOX4.
- Monitored autophagic flux with the mRFP-GFP-LC3 plasmid and assessed ROS generation using a GOX/CAT system.
Main Results:
- Acute ethanol exposure induced autophagy (LC3B expression) and ROS-generating enzymes (CYP2E1, NOX4) in mice.
- Ethanol, but not acetaldehyde, induced autophagy in primary hepatocytes; CYP2E1 and NOX4 overexpression enhanced autophagy in Huh7 cells.
- ROS, specifically hydrogen peroxide (H2O2), directly induced autophagy and autophagic flux, an effect blocked by the antioxidant N-acetylcysteine (NAC).
Conclusions:
- Short-term ethanol exposure triggers autophagy in hepatocytes via ROS generation, both in vivo and in vitro.
- Autophagy suppression observed in chronic alcohol consumption may stem from prolonged exposure and subsequent accumulation of misfolded proteins.
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