Temporal profiling of the secretome during adipogenesis in humans.
Adipose tissue plays a key role as a fat-storage depot and as an endocrine organ. Although mouse adipogenesis has been studied extensively, limited studies have been conducted to characterize this process in humans. We carried out a temporal proteomic analysis to interrogate the dynamic changes in the secretome of primary human preadipocytes as they differentiate into mature adipocytes. Using iTRAQ-based quantitative proteomics, we identified and quantified 420 proteins from the secretome of differentiated human adipocytes. Our results revealed that the majority of proteins showed differential expression during the course of differentiation. In addition to adipokines known to be differentially secreted in the course of adipocyte differentiation, we identified a number of proteins whose dynamic expression in this process has not been previously documented. They include collagen triple helix repeat containing 1, cytokine receptor-like factor 1, glypican-1, hepatoma-derived growth factor, SPARC related modular calcium binding protein 1, SPOCK 1, and sushi repeat-containing protein. A bioinformatics analysis using Human Protein Reference Database and Human Proteinpedia revealed that of the 420 proteins identified, 164 proteins possess signal peptides and 148 proteins are localized to the extracellular compartment. Additionally, we employed antibody arrays to quantify changes in the levels of 182 adipokines during human adipogenesis. This is the first large-scale quantitative proteomic study that combines two platforms, mass spectrometry and antibody arrays, to analyze the changes in the secretome during the course of adipogenesis in humans.
Zhong
Jun
J
McKusick-Nathans Institute of Genetic Medicine, Departments of Biological Chemistry, Oncology, Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Krawczyk
Sarah A
SA
Chaerkady
Raghothama
R
Huang
Hailiang
H
Goel
Renu
R
Bader
Joel S
JS
Wong
G William
GW
Corkey
Barbara E
BE
Pandey
Akhilesh
A
D017667:Adipocytes / Q000166:cytology / Q000378:metabolism; D050156:Adipogenesis; D000328:Adult; D002454:Cell Differentiation; D002478:Cells, Cultured; D002853:Chromatography, Liquid; D019295:Computational Biology / Q000379:methods; D030562:Databases, Protein; D005260:Female; D006801:Humans; D013058:Mass Spectrometry; D008875:Middle Aged; D020543:Proteome / Q000032:analysis* / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D050151:Subcutaneous Fat / Q000166:cytology / Q000378:metabolism; D013997:Time Factors
D020543:Proteome