Proteomic Analysis of Exosomes from Adipose-Derived Mesenchymal Stem Cells: A Novel Therapeutic Strategy for Tissue Injury

Abstract

Exosomes are extracellular membranous nanovesicles that mediate local and systemic cell-to-cell communication by transporting functional molecules, such as proteins, into target cells, thereby affecting the behavior of receptor cells. Exosomes originating from adipose-derived mesenchymal stem cells (ADSCs) are considered a multipotent and abundant therapeutic tool for tissue injury. To investigate ADSC-secreted exosomes and their potential function in tissue repair, we isolated exosomes from the supernatants of ADSCs via ultracentrifugation, characterized them via transmission electron microscopy, nanoparticle tracking analysis, and Western blot analysis. Then, we determined their protein profile via proteomic analysis. Results showed that extracellular vesicles, which have an average diameter of 116 nm, exhibit a cup-shaped morphology and express exosomal markers. A total of 1,185 protein groups were identified in the exosomes. Gene Ontology analysis indicated that exosomal proteins are mostly derived from cells mainly involved in protein binding. Protein annotation via the Cluster of Orthologous Groups system indicated that most proteins were involved in general function prediction, posttranslational modification, protein turnover, and chaperoning. Further, pathway analysis revealed that most of the proteins obtained participated in metabolic pathways, focal adhesion, regulation of the actin cytoskeleton, and microbial metabolism. Some tissue repair-related signaling pathways were also discovered. The identified molecules might serve as potential therapeutic targets for future studies.

In Vitro Cultures of Adipose-Derived Stem Cells: An Overview of Methods, Molecular Analyses, and Clinical Applications

“…Proteomic analysis of exosomes originating from ASCs has revealed expression of proteins typical of cells responsible for protein binding, mostly participating in function prediction, posttranslational modification, and chaperoning. Some proteins detected are commonly involved in metabolic pathways, focal adhesion, regulation of the actin cytoskeleton, and microbial metabolism, together with tissue repair-related signaling pathways, such as putative paracrine effectors of angiogenesis including platelet-derived growth factor, epidermal growth factor, fibroblast growth factor, and nuclear factor kappa B (NF-κB) signaling pathway proteins [58].…”

The role of small extracellular vesicles in cerebral and myocardial ischemia—Molecular signals, treatment targets, and future clinical translation

“…Many signaling cascades were found to be affected by EVs. Among these, the VEGF and STAT3 pathways are noteworthy, triggering poststroke angiogenesis and tissue regeneration in vitro and in vivo via mechanisms that involve the inhibition of autophagy 59,60 . The molecular targets and functions of MSC‐derived miRNAs and proteins under conditions of cerebral ischemia are summarized in Table 1.…”

Deciphering Adipose Tissue Extracellular Vesicles Protein Cargo and Its Role in Obesity

“…Thus, they suggest that EVs have a selectively-enriched protein cargo with a specific biological signature that ADSCs may utilize for intercellular communication to ease tissue repair. Additionally, a proteomics analysis of the exosomes secreted by ADSCs to elucidate their potential role as therapeutic strategy for tissue injury has been published [ 46 ]. In their work, they mention 1185 protein groups, many of them participating in metabolic pathways, focal adhesion, regulation of actin cytoskeleton, microbial metabolism, and more interesting, some belonged to tissue repair-related signaling pathways.…”