Resveratrol Suppresses Oxidised Low-Density Lipoprotein-Induced Macrophage Apoptosis through Inhibition of Intracellular Reactive Oxygen Species Generation, LOX-1, and the p38 MAPK Pathway

Abstract

Background/Aim: Resveratrol (RSV) may have therapeutic potential for various diseases. Here we investigated the effect of RSV on oxidised low-density lipoprotein- (ox-LDL) induced apoptosis in RAW264.7 macrophages. Methods: Apoptosis of macrophages following incubation with ox-LDL (with or without RSV pre-treatment) was detected by flow cytometry. Western blotting was used to assess the protein expression of Bax, Bcl-2, and caspase-3 as well as ox-LDL receptor 1 (LOX-1) and p38 mitogen-activated protein kinase (MAPK) phosphorylation. Reactive oxygen species (ROS) generation was evaluated by 2', 7'-dichlorofluorescein diacetate, and JC-1 probe was used to determine the mitochondrial transmembrane potential of cells. Results: Ox-LDL significantly reduced viability and increased the rate of apoptosis (P < 0.05) in RAW264.7 cells. However, pre-treatment with RSV resulted in a remarkable decrease in this apoptotic effect. Moreover, ox-LDL caused the up-regulation of Bax and the down-regulation of Bcl-2, as well as the activation of caspase-3. Expression of LOX-1, phosphorylation of p38 MAPK, and intracellular ROS production also increased after ox-LDL stimulation. Strikingly, these effects were abolished by pre-treatment of cells with RSV. Conclusion: RSV suppresses ox-LDL-induced macrophage apoptosis. These beneficial effects might be exerted through inhibition of ROS generation, LOX-1, and the p38 MAPK signalling pathway.