Site-specific proteomic analysis of lipoxidation adducts in cardiac mitochondria reveals chemical diversity of 2-alkenal adduction

The modification of proteins by lipid peroxidation products has been linked to numerous diseases and age-related disorders. Here we report on the identification of endogenous protein targets of electrophilic 2-alkenals in cardiac mitochondria. An aldehyde/keto-specific chemical labeling and affinity strategy in combination with LC–MS/MS resulted in 39 unique lipoxidation sites on 27 proteins. Several of the target sites were modified by a variety of 2-alkenal products including acrolein, β-hydroxyacrolein, crotonaldehyde, 4-hydroxy-2-hexenal, 4-hydroxy-2-nonenal and 4-oxo-2-nonenal. Many of the adduction sites are implicated in the catalytic function of key mitochondrial enzymes suggesting potential impact on pathways and overall mitochondrial function.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (78 K)Download as PowerPoint slideHighlights► Endogenous protein targets of electrophilic 2-alkenals in cardiac mitochondria. ► Aldehyde/keto-specific labeling and affinity strategy in conjunction with LC-MS/MS. ► Distinct target sites were modified by a variety of 2-alkenal products.