Quantitative proteomics reveals differential regulation of protein expression in recipient myocardium after trilineage cardiovascular cell transplantation

Abstract

Intramyocardial transplantation of cardiomyocytes (CMs), endothelial cells (ECs), and smooth muscle cells (SMCs) derived from human induced pluripotent stem cells (hiPSCs) has beneficial effects on the post-infarction heart. However, the mechanisms underlying the functional improvements remain undefined. We employed large-scale label-free quantitative proteomics to identify proteins that were differentially regulated following cellular transplantation in a swine model of myocardial infarction (MI). We identified 22 proteins that were significantly up-regulated after trilineage cell transplantation compared to both MI and Sham groups. Among them, 12 proteins, including adenylyl cyclase-associated protein 1 and tropomodulin-1, are associated with positive regulation of muscular contraction whereas 11 proteins, such as desmoplakin and zyxin, are involved in embryonic and muscular development and regeneration. Moreover, we identified 21 proteins up-regulated and another 21 down-regulated in MI, but reversed after trilineage cell transplantation. Proteins up-regulated after MI but reversed by transplantation are related to fibrosis and apoptosis. Conversely, proteins down-regulated in MI but restored after cell therapy are regulators of protein nitrosylation. Our results show that the functionally beneficial effects of trilineage cell therapy are accompanied by differential regulation of protein expression in the recipient myocardium, which may contribute to the improved cardiac function.

Intramyocardial Injection of Recombinant Adeno‐Associated Viral Vector Coexpressing PR39/Adrenomedullin Enhances Angiogenesis and Reduces Apoptosis in a Rat Myocardial Infarction Model

“…Recently, new molecular and cellular targets together with genomic, proteomic, and other biotechnological advances have led to the discovery of novel pharmaceutical agents for the treatment of MI [ 25 ]. Chang et al reported that the functional benefits of cell therapy were accompanied by differential regulation of protein expression in the recipient myocardium, which might contribute to the improved cardiac function [ 26 ]. The administration of growth factors, with the aim of promoting angiogenesis, chemotaxis, stem cell differentiation, cardiomyocyte survival and proliferation, reduction of apoptosis, and remodelling, holds great promise as a therapy for MI [ 25 ].…”

Simultaneous Quantification of Protein Expression and Modifications by Top-down Targeted Proteomics: A Case of the Sarcomeric Subproteome

“…For example, bottom-up proteomics typically does not distinguish protein isoforms with high sequence homology and may yield inconsistent results in the determination of protein expression especially in the label-free quantification using multiple peptides from the same protein (17). Therefore, antibody-based assays are often necessary for the validation of the protein expression changes obtained from the bottom-up proteomics data set (12,18,19).…”

Temperature-sensitive sarcomeric protein post-translational modifications revealed by top-down proteomics

“…It is important to point out that many truncated proteoforms of cTnI and cTnT have similar molecular weight as the intact proteoforms, therefore making the detection of such truncated proteoforms difficult and ambiguous via the gel electrophoresis approach. Moreover, although the conventional bottom- up approach is capable of identifying and quantifying thousands of proteins from a complex mixture [71, 72], due to limited sequence coverage as a result of proteolytic digestion, it remains challenging to distinguish highly homologous protein isoforms and proteolytic products with small truncation. On the contrary, top-down MS-based proteomics approach permits the analysis of intact proteins and unambiguously reveals the existing proteoforms including those with small truncation <1000 Da, as well as those with distinct sequence variations [73].…”