Lipid Peroxidation: Production, Metabolism, and Signaling Mechanisms of Malondialdehyde and 4-Hydroxy-2-Nonenal

Figure 6

4-HNE promotes cell survival or induces cell death. Depending on cell type, damage/repair capacities and cellular metabolic circumstances 4-HNE can promote cell survival or induce cell death. 4-HNE at physiological levels is enzymatically metabolized and at low levels plays an important role as signaling molecule stimulating gene expression, enhance cellular antioxidant capacity and exert adaptive response; at medium levels organelle and protein damage lead to induction of autophagy, senescence, or cell cycle arrest and at high or very high levels promote adducts formation and apoptosis or necrosis cell death, respectively.