Comparative Expression of Proteins in Left and Right Atrial Appendages From Patients With Mitral Valve Disease at Sinus Rhythm and Atrial Fibrillation

Abstract

For each individual patient RAA and LAA showed a similar level of proteins expressed associated with cytoskeleton, energetic metabolism, and cardiac cytoprotection. There were more differences in the level of proteins associated with the above-mentioned mechanisms between the atrial appendages from AF with respect to SR patients, which may open new targets for drugs.

Quantitative Proteomics of Changes in Energy Metabolism-Related Proteins in Atrial Tissue From Valvular Disease Patients With Permanent Atrial Fibrillation

“…12-14 The 2 previous proteomics studies, however, were focused on the upregulated proteins in the atrium of AF patients. 25, 26 In the present study, we found that few proteins were upregulated and many proteins were downregulated in the LA of AF patients. Western blot was done to further validate the iTRAQ results.…”

“…25 The expression of isocitrate dehydrogenase is not different between AF and SR patients. 26 In the present study, compared to the upregulated proteins, we found many other carbohydrate metabolism-related proteins were downregulated in AF patients, which may contribute to the impaired energy production coninward rectifier K + current function between the RA and LA in SR and AF patients, and found that paroxysmal AF patients had inward rectifier current densities that were 2-fold larger in the LA than in the RA cardiomyocytes. 21 Those findings provide a molecular basis for AF-maintaining LA drivers.…”

“…42 A recent proteomics study found that many energy metabolism proteins were expressed differently in the LAA of AF patients compared to SR patients. 26 Although atrial growth was correlated with only 1 energy metabolism protein, 26 the influence of LA size on energy metabolism should not be neglected. Meanwhile, valvular heart disease often leads to AF through changing gene, mRNA and even ion-channel protein expression.…”

Mitral Regurgitation and Atrial Fibrillation: The Contribution of Impaired Left Atrial Appendage Function to Atrial Thrombogenesis

“…Similar levels of protein expression is been reported both in RAA and LAA samples. However, expression of cardiac alpha-actin isotypes 1 and 2, tropomyosin alpha-and beta-chains, and myosin light chain embryonic muscle/atrial isoform in LAA from AF patients was found increased when compared to those from SR patients [24]. Another potential contributor to atrial remodelling, cardiac endothelin-1 (ET-1), is expressed as a response to wall stress and can promote myocyte hypertrophy and interstitial fibrosis [25].…”

Proteomics of Atrial Fibrillation

“…Modrego et al 38 compared protein expression in both left atrial appendage and RAA taken from patients with mitral valve disease in the presence and absence of AF. The authors focused on proteins associated with 3 main biological functions: cytoskeleton, energetic metabolism, and cardiac cytoprotection.…”