Antioxidant Clove Extract Inhibits Lipid Droplet Accumulation and Lipid Oxidation in Hepatocytes

Background: Recent studies have shown that plant-based dietary extracts can prevent the formation of lipid droplets (LDs) and oxidized lipid droplets (oxLDs) in liver cells. These results indicate that these extracts might be useful in addressing metabolic dysfunction-associated fatty liver disease (MAFLD) and its more severe form, metabolic dysfunction-associated steatohepatitis (MASH). In our ongoing study, we evaluated the potential of various food extracts to inhibit the accumulation and oxidation of LDs in liver cells to prevent metabolic MAFLD and MASH. Methods: The antioxidant activity index was determined using the DPPH assay, cell viability was assessed via cytotoxicity and lipotoxicity, and lipid droplet accumulation inhibition (LDAI) assays were performed. Metabolome analysis was performed using 1D-NMR [¹H, ¹³C, DEPT 90, and 135] techniques. Results: Dietary clove (Syzygium aromaticum) extract exhibited antioxidant properties and inhibited linoleic acid-induced lipid droplet (LD) accumulation (LDA) and oxidized LDA (oxLDA) in HepG2 cells. Additionally, an analysis of the metabolome of dietary clove bioactive LDAI using 1D-NMR showed that clove extract (CE) mainly consists of hydroxybenzoic acids (HBAs) and hydroxycinnamic acids (HCAs), along with minor amounts of carbohydrates, coumarins, polyphenolic compounds, and small quantities of polyols, fatty acyls, small peptides, and amino acids. This suggests that CE could be a promising resource for developing functional foods and nutraceuticals and discovering drugs for treating MAFLD, MASH, and related conditions.