Apricot Melanoidins Prevent Oxidative Endothelial Cell Death by Counteracting Mitochondrial Oxidation and Membrane Depolarization

The cardiovascular benefits associated with diets rich in fruit and vegetables are thought to be due to phytochemicalscontained in fresh plant material. However, whether processed plant foods provide the same benefits as unprocessed onesis an open question. Melanoidins from heat-processed apricots were isolated and their presence confirmed by colorimetricanalysis and browning index. Oxidative injury of endothelial cells (ECs) is the key step for the onset and progression ofcardiovascular diseases (CVD), therefore the potential protective effect of apricot melanoidins on hydrogen peroxideinducedoxidative mitochondrial damage and cell death was explored in human ECs. The redox state of cytoplasmic andmitochondrial compartments was detected by using the redox-sensitive, fluorescent protein (roGFP), while themitochondrial membrane potential (MMP) was assessed with the fluorescent dye, JC-1. ECs exposure to hydrogenperoxide, dose-dependently induced mitochondrial and cytoplasmic oxidation. Additionally detected hydrogen peroxideinducedphenomena were MMP dissipation and ECs death. Pretreatment of ECs with apricot melanoidins, significantlycounteracted and ultimately abolished hydrogen peroxide-induced intracellular oxidation, mitochondrial depolarization andcell death. In this regard, our current results clearly indicate that melanoidins derived from heat-processed apricots, protecthuman ECs against oxidative stress.