Oleuropein attenuates placental growth factor expression by regulating oxidative stress and apoptosis in acrylamide hepatotoxicity

The liver is susceptible to toxic effects, as it is the main site of acrylamide biotransformation and detoxification. Researchers have claimed that placental growth factor (PlGF) and its pathway are potentially involved in numerous diseases, including liver fibrosis and angiogenesis. Oleuropein is a natural phenolic compound with potent antioxidant effects. The purpose of this study was to examine the role of PlGF and the potential protection provided by oleuropein in acrylamide hepatotoxicity. Wistar albino rats were assigned into control, acrylamide (ACR) (5 mg/kg), oleuropein (OLE) (4.2 mg/kg), and ACR+OLE groups. Acrylamide and oleuropein were administered for 21 days. The control group received only physiological saline. Liver tissues were evaluated histologically and immunohistochemically. Histological examinations revealed significant enlargement of the sinusoidal vessels and abundant hepatocytes with pyknotic nuclei in the ACR group. Acrylamide toxicity resulted in elevated PlGF, accumulation of 8-hydroxydeoxyguanosine (8-OHdG), and increased Caspase-3 immunoreactivity in the liver. Oleuropein treatment reduced the increased expression of PlGF, 8-OHdG, and Caspase-3 against these deleterious effects observed in the ACR group. A positive correlation was observed between PlGF levels as well as oxidative stress and apoptosis markers in acrylamide toxicity. Oleuropein probably counteracted this mechanism by exhibiting antioxidant activity.