4-hydroxy Nonenal is a lipid peroxidation product derived from oxidized ω-6 polyunsaturated fatty acids such as arachidonic acid. 4-hydroxy Nonenal is widely used as a marker of lipid peroxidation. It exhibits various biological activities such as cytotoxicity, growth inhibiting activity, genotoxicity, and chemotactic activity. 4-hydroxy Nonenal inhibits pro-oxidant-induced Ca2+ release from mitochondria at 10-50 μM.