4HNE Impairs Myocardial Bioenergetics in Congenital Heart Disease-Induced Right Ventricular Failure

Abstract

Background: In patients with complex congenital heart disease, such as those with tetralogy of Fallot, the right ventricle (RV) is subject to pressure overload stress, leading to RV hypertrophy and eventually RV failure. The role of lipid peroxidation, a potent form of oxidative stress, in mediating RV hypertrophy and failure in congenital heart disease is unknown. Methods: Lipid peroxidation and mitochondrial function and structure were assessed in RV myocardium collected from patients with RV hypertrophy with normal RV systolic function (RV FAC 47.3±3.8%) and in patients with RV failure showing decreased RV systolic function (RV FAC 26.6±3.1%). The mechanism of the effect of lipid peroxidation, mediated by 4-hydroxynonenal (4HNE; a byproduct of lipid peroxidation) on mitochondrial function and structure was assessed in HL1 murine cardiomyocytes and human induced pluripotent stem cellderived cardiomyocytes. Results: RV failure was characterized by an increase in 4HNE adduction of metabolic and mitochondrial proteins (16/27 identified proteins), in particular electron transport chain proteins. Sarcomeric (myosin) and cytoskeletal proteins (desmin, tubulin) also underwent 4HNEadduction. RV failure showed lower oxidative phosphorylation [moderate RV hypertrophy 287.6±19.75 vs. RV failure 137.8±11.57 pmol/(sec*ml), p=0.0004], and mitochondrial structural damage. Using a cell model, we show that 4HNE decreases cell number and oxidative phosphorylation (control 388.1±23.54 vs. 4HNE 143.7±11.64 pmol/(sec*ml), p<0.0001). Carvedilol, a known antioxidant did not decrease 4HNE adduction of metabolic and mitochondrial proteins and did not improve oxidative phosphorylation. Conclusions: Metabolic, mitochondrial, sarcomeric and cytoskeletal proteins are susceptible to 4HNE-adduction in patients with RV failure. 4HNE decreases mitochondrial oxygen consumption by inhibiting electron transport chain complexes. Carvedilol did not improve the 4HNE-mediated decrease in oxygen consumption. Strategies to decrease lipid peroxidation could improve mitochondrial energy generation and cardiomyocyte survival and improve RV failure in patients with congenital heart disease.

4-Hydroxy-2-Nonenal Promotes Cardiomyocyte Necroptosis via Stabilizing Receptor-Interacting Serine/Threonine-Protein Kinase 1

“…During MI/R injury, 4-HNE is increased by 6-fold in reperfusioninjured hearts to 100 µM (Lucas and Szweda, 1999). Accumulation of 4-HNE increases the formation of 4-HNE adducts by binding to various proteins in the heart tissue and promotes cardiac dysfunction mainly through damaging mitochondria, impairing ATP production, and inducing cardiomyocyte death (Hwang et al, 2020;Santin et al, 2020). The role of 4-HNE in cardiomyocyte apoptosis was previously investigated, but the effects of 4-HNE on cardiomyocyte necroptosis remain unknown (Sun et al, 2014).…”

Accelerated Cardiac Aging in Patients With Congenital Heart Disease

“…A study conducted on TOF patients with RV hypertrophy showed an increase of 4-HNE on mitochondrial function and structure. This bioproduct of lipid peroxidation, a form of oxidative stress in aging heart, altered the energy production in the mitochondrion of RV leading to its failure and cardiomyocyte dysfunction ( 209 ). An in vivo genetic model of mitochondrial dysfunction has been achieved by inactivating the mitochondrial transcription factor A ( tfam ), which resulted in elevated ROS production and activated DNA damage response, thus causing cardiomyocyte cell cycle arrest and ultimately lethal cardiomyopathy ( 210 ).…”

GDAP1 binds 4-hydroxynonenal, the toxic end-product of lipid peroxidation, using its GST-like binding pocket

“…Increased levels of 4HNE resulting from oxidative stress can result in 4HNE adduct formation, a mechanism known to damage and inactivate proteins, especially those involved in energy production within the mitochondria (Hwang et al, 2020). We first asked whether exposure to 4HNE can produce similar covalent adducts with GDAP1 using GDAP1ΔTM.…”

“…These reactive end products of lipid peroxidation are cytotoxic: MDA can react with guanosine bases in DNA to form the mutagenic DNA adduct M1dG (Marnett, 1999), while both MDA and 4HNE can form Michael adducts or Schiff bases with thiol and amine groups within proteins (Ayala et al, 2014; Esterbauer et al, 1991). 4HNE adduct formation has been shown to inactivate many proteins including cytochrome c oxidase and reductase (Chen et al, 1998; Hwang et al, 2020), and treatment of cells with 4HNE has demonstrated that hundreds of cellular proteins are sensitive to 4HNE adduct formation (Roe et al, 2007; Vila et al, 2008).…”