Bioactive constituents of Olea europaea L. leaf extract ameliorate metabolic-associated steatohepatitis via the PPARγ/AMPK/ACC Axis

The therapeutic potential of Olea europaea L. leaf in hepatitis is recognized, yet its active constituents against metabolic dysfunction-associated steatohepatitis (MASH), a specific form of hepatitis driven by metabolic disturbances, remain poorly defined. This study integrated HPLC fingerprinting of Olea europaea L. leaf extracts (OLE) with chemometrics and bioactivity profiling to identify anti-MASH components. Bioactivity was assessed using a palmitic acid-induced steatohepatitis model in L02 cells. Spectrum–effect relationships derived from pearson correlation and partial least squares regression highlighted four putative active compounds, designated P7, P8, P10, and P11. HPLC-MS identified these as cynaroside (P7), apigenin-7-O-glucoside (P8), oleuroside (P10), and ligustroside (P11). Subsequent in vitro and in vivo evaluations in a zebrafish MASH model confirmed that P7, P8, and P10 exhibited significant anti-MASH activity. Notably, a robust synergism was observed between cynaroside and oleuroside, which their 1:1 M combination yielded a ZIP synergy score of 11.965 and a combination index (CI) of 0.3151, indicating strong synergy at lower doses. These results identify key anti-MASH constituents in OLE and provide a mechanistic basis for using multi-component OLE, highlighting a synergistic approach for MASH management. • Olea europaea L. leaf extract (OLE) ameliorates MASH in a novel high-fat/high-sucrose diet-induced zebrafish model. • OLE alleviates glucolipotoxicity in both human L02 hepatocytes and zebrafish. • Spectrum-effect relationship analysis identified four key anti-MASH polyphenols (cynaroside, apigenin-7-glucoside, oleuroside, ligstroside). • Molecular docking reveals multi-target synergy via the PPARγ/AMPK/ACC axis. • Findings support OLE's potential as a multi-target natural supplement for MASH.