Hepatoprotective Activity of Prunus laurocerasus Fruit Extract Against 5-FU-Induced Liver Injury and LC-MS/MS Profiling

5-Fluorouracil (5-FU), one of the most widely used chemotherapy drugs, is known to cause widespread toxicity and irreparable tissue damage. The purpose of this work was to analyze the phytochemical components of Prunus laurocerasus (PL) fruit extract using liquid chromatography with tandem mass spectrometry (LC-MS/MS) and to look into the effectiveness of PL pretreatment on 5-FU-induced liver damage. The study consisted of control (C), PL, 5-FU, PL+5-FU groups, and PL groups received 500 mg/kg PL as pretreatment for seven days. On the eighth day, 100 mg/kg 5-FU was administered intraperitoneally as a single dose to the PL+5-FU and 5-FU groups. In the LC-MS/MS results, it was determined that the phenolic compounds found in the foreground in PL were quinic acid and chlorogenic acid. PL pretreatment increased total antioxidant status levels and B-cell lymphoma 2 (Bcl-2) expression and also decreased Keap1, total oxidant status, oxidative stress index levels, and Bcl-2-associated X protein, Caspase-3, and light chain-3B expressions. 8-hydroxy-2'-deoxyguanosine levels were higher in the 5-FU group compared to the C and PL groups. Moreover, in the PL+5-FU group, the levels were similar to the C, PL, and 5-FU groups. In conclusion, PL pretreatment demonstrated hepatoprotective action via regulating the Kelch-like ECH-associated protein 1/nuclear factor-erythroid 2-related factor 2 pathway in 5-FU-induced liver damage, lowering oxidative stress, and decreasing apoptosis and autophagy from programmed cell death. © 2025 Wiley-VHCA AG, Zurich, Switzerland.