Related Experiment Video
Updated: Mar 20, 2026
08:35
A Model of Experimental Steatosis In Vitro: Hepatocyte Cell Culture in Lipid Overload-Conditioned Medium
Published on: May 18, 2021
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Lipid overload triggers PERK-ALCAT1-mediated mitophagy failure in hepatocytes
Wenli Zhao1,2,3, Yangguang Bao1,2,3, Lei Liu1
1Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo 315211, China.
Iscience
|March 19, 2026
Summary
High-fat diets cause liver damage by disrupting mitochondria-associated membranes (MAMs). Resveratrol treatment restores mitochondrial function by targeting the SIRT1-PERK-ALCAT1 pathway, offering a nutritional intervention for fatty liver disease.
Area of Science:
- Cell Biology
- Metabolic Disease Research
- Mitochondrial Dynamics
Background:
- Mitochondria-associated endoplasmic reticulum membranes (MAMs) are crucial for cellular calcium and lipid homeostasis.
- The role of MAMs in lipid overload-induced fatty liver disease (MASLD) and mitochondrial dysfunction is not fully understood.
Purpose of the Study:
- To investigate the mechanism by which MAMs contribute to mitochondrial dysfunction in fatty liver disease.
- To identify potential therapeutic targets for metabolic dysfunction-associated steatotic liver disease (MASLD).
Main Methods:
- Utilized teleost fish as a model organism to study high-fat diet-induced liver injury.
- Examined the interaction between PERK and ALCAT1 at MAMs and their impact on mitochondrial calcium and mitophagy.
- Investigated the role of SIRT1 activation by resveratrol in modulating PERK acetylation and restoring mitochondrial function.
Main Results:
- High-fat diets led to PERK and ALCAT1 aggregation at MAMs, causing mitochondrial calcium overload, depolarization, and impaired mitophagy.
- PERK acetylation at lysine 388 enhanced its binding to ALCAT1.
- Resveratrol-activated SIRT1 deacetylated PERK, disrupting the PERK-ALCAT1 interaction and restoring mitophagy and mitochondrial integrity.
Conclusions:
- A conserved SIRT1-PERK-ALCAT1 signaling axis links endoplasmic reticulum stress to mitophagy failure in fatty liver disease.
- Targeting this pathway with nutritional interventions like resveratrol shows promise for alleviating lipid-induced hepatic injury.
- This mechanism provides a basis for managing MASLD in teleosts and potentially other vertebrates.
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