4-Hydroxynonenal (HNE) and hepatic injury related to chronic oxidative stress

Abstract 4-Hydroxynonenal (HNE), a major end-product of free-radical activated peroxidation of polyunsaturated fatty acids, has attracted great scientific interest. HNE is more stable than free radicals and can diffuse within the cell or leave it and react with targets far from the initial site. These reactive aldehyde species are considerably reactive, producing multiple intra- and inter-molecular covalent adducts with biomolecules such as proteins, DNA and phospholipids. HNE is the most intensively studied aldehyde in relation to its physiological and protective function as a signalling molecule that stimulates gene expression and cell survival, as well as for its pathophysiological role as a toxic messenger that can propagate and amplify oxidative injury and promote mitochondrial dysfunction and cell death. Non-alcoholic fatty liver disease (NAFLD) is the most prevalent form of chronic liver disease in the world associated with oxidative stress, mitochondrial dysfunction and hepatocellular apoptosis. In this review we focus our attention on the molecular mechanism of the signalling and regulatory action of HNE. The role of HNE as a potent mediator for progression of liver injury in NAFLD is also discussed