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Updated: May 3, 2026
A Model of Experimental Steatosis In Vitro: Hepatocyte Cell Culture in Lipid Overload-Conditioned Medium
Published on: May 18, 2021
PPAR agonists reduce steatosis in oleic acid-overloaded HepaRG cells
Alexandra Rogue1, Sébastien Anthérieu2, Aurore Vluggens2
1Inserm UMR 991, 35043 Rennes Cedex, France; Université de Rennes 1, Faculté des Sciences Pharmaceutiques et Biologiques, 35043 Rennes Cedex, France; Biologie Servier, Gidy, France.
Unlabelled:
Although non-alcoholic fatty liver disease (NAFLD) is currently the most common form of chronic liver disease there is no pharmacological agent approved for its treatment. Since peroxisome proliferator-activated receptors (PPARs) are closely associated with hepatic lipid metabolism, they seem to play important roles in NAFLD. However, the effects of PPAR agonists on steatosis that is a common pathology associated with NAFLD, remain largely controversial. In this study, the effects of various PPAR agonists, i.e. fenofibrate, bezafibrate, troglitazone, rosiglitazone, muraglitazar and tesaglitazar on oleic acid-induced steatotic HepaRG cells were investigated after a single 24-hour or 2-week repeat treatment. Lipid vesicles stained by Oil-Red O and triglycerides accumulation caused by oleic acid overload, were decreased, by up to 50%, while fatty acid oxidation was induced after 2-week co-treatment with PPAR agonists. The greatest effects on reduction of steatosis were obtained with the dual PPARα/γ agonist muraglitazar. Such improvement of steatosis was associated with up-regulation of genes related to fatty acid oxidation activity and down-regulation of many genes involved in lipogenesis. Moreover, modulation of expression of some nuclear receptor genes, such as FXR, LXRα and CAR, which are potent actors in the control of lipogenesis, was observed and might explain repression of de novo lipogenesis.
Conclusion:
Altogether, our in vitro data on steatotic HepaRG cells treated with PPAR agonists correlated well with clinical investigations, bringing a proof of concept that drug-induced reversal of steatosis in human can be evaluated in in vitro before conducting long-term and costly in vivo studies in animals and patients.
Insights
PPAR agonists reduced fat accumulation in liver cells, improving fatty acid oxidation. Dual PPARα/γ agonist muraglitazar showed the greatest effect, validating in vitro models for non-alcoholic fatty liver disease (NAFLD) drug development.
Area of Science:
- Hepatology and Pharmacology
- Molecular Biology
- Drug Discovery
Background:
- Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver condition, yet lacks approved pharmacological treatments.
- Peroxisome proliferator-activated receptors (PPARs) regulate hepatic lipid metabolism, implicating them in NAFLD pathogenesis.
- The impact of PPAR agonists on NAFLD-associated steatosis remains debated.
Purpose of the Study:
- To investigate the effects of various PPAR agonists on oleic acid-induced steatosis in HepaRG cells.
- To evaluate the efficacy of single and repeated treatments with PPAR agonists.
- To explore the molecular mechanisms underlying steatosis reversal by PPAR agonists.
Main Methods:
- Utilized HepaRG cells induced with oleic acid to model steatosis.
- Administered various PPAR agonists (fenofibrate, bezafibrate, troglitazone, rosiglitazone, muraglitazar, tesaglitazar) for 24 hours or 2 weeks.
- Quantified lipid accumulation using Oil-Red O staining and measured triglyceride levels.
- Assessed fatty acid oxidation and gene expression related to lipid metabolism, lipogenesis, and nuclear receptors (FXR, LXRα, CAR).
Main Results:
- Two-week co-treatment with PPAR agonists significantly reduced lipid vesicles and triglyceride accumulation by up to 50%.
- Fatty acid oxidation was induced following the 2-week treatment.
- The dual PPARα/γ agonist muraglitazar demonstrated the most potent steatosis-reducing effects.
- Observed were upregulated genes involved in fatty acid oxidation and downregulated genes in lipogenesis.
- Modulation of FXR, LXRα, and CAR gene expression suggested a mechanism for repressing de novo lipogenesis.
Conclusions:
- In vitro data using steatotic HepaRG cells and PPAR agonists align with clinical findings.
- This study provides a proof of concept for evaluating drug-induced steatosis reversal in vitro.
- In vitro models offer a viable platform for assessing therapeutic strategies before extensive in vivo studies.
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