# Aspirin Eugenol Ester Ameliorates HFD-Induced NAFLD in Mice via the Modulation of Bile Acid Metabolism

## TL;DR

Aspirin eugenol ester helps reduce fatty liver disease in mice by improving bile acid metabolism and lowering fat levels.

## Contribution

AEE is shown to ameliorate NAFLD through modulation of bile acid metabolism and lipid regulation in both cell and animal models.

## Key findings

- AEE reduced lipid droplet area and cholesterol and triglyceride levels in cell models.
- AEE improved liver steatosis and reduced glycogen accumulation in mice fed a high-fat diet.
- AEE reversed HFD-induced metabolite changes in liver and serum, affecting seven key metabolic pathways.

## Abstract

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent condition worldwide and represents a major global health challenge. Pharmacological and pharmacodynamic results indicate that aspirin eugenol ester (AEE) performs various pharmacological activities. However, it is unclear whether AEE can ameliorate the NAFLD. This study investigated the ameliorative effects of AEE on glucose and lipid metabolism disorders by in vitro and in vivo experiments. In the cellular model, TC increased to 0.104 μmol/mg and TG increased to 0.152 μmol/mg in the model group, while TC decreased to 0.043 μmol/mg and TG decreased to 0.058 μmol/mg in the AEE group. In the model group, the area occupied by lipid droplets within the visual field was significantly elevated to 17.338%. However, the administration of AEE resulted in a substantial reduction in this area to 10.064%. AEE significantly reduced the lipid droplet area and TC and TG levels (p < 0.05), increased bile acids in the cells and in the medium supernatant (p < 0.05), and significantly up-regulated the expression of LRH-1, PPARα, CYP7A1, and BSEP mRNA levels (p < 0.05) compared to the model group. In the animal model, different doses of AEE administration significantly down-regulated the levels of TC, TG, LDL, GSP, and FBG (p < 0.05) compared to the high-fat-diet (HFD) group, and 216 mg/kg of AEE significantly improved hepatocellular steatosis, attenuated liver injury, and reduced the area of glycogen staining (p < 0.05). In the HFD group, the glycogen area within the visual field exhibited a significant increase to 18.250%. However, the administration of AEE resulted in a notable reduction in the glycogen area to 13.314%. Liver and serum metabolomics results show that AEE can reverse the metabolite changes caused by a HFD. The major metabolites were involved in seven pathways, including riboflavin metabolism, glycerophospholipid metabolism, tryptophan metabolism, primary bile acid biosynthesis, biosynthesis of unsaturated fatty acids, nicotinate and nicotinamide metabolism, and tryptophan metabolism. In conclusion, AEE had a positive regulatory effect on NAFLD.