The proteomics of adipose tissue
Obesity is a widespread disease both in the UK and worldwide and the prevalence is increasing in epidemic proportions. This increased weight and altered body fat distribution has brought about increased risk of comorbid disease such as type II diabetes, hypertension and cardiovascular disease. The aim of this study was to find novel proteins differentially expressed in subcutaneous and omental adipose tissue. To achieve this, approaches to resolve adipose tissue adequately using two-dimensional electrophoresis (2DE) were developed to allow the detection of differences in protein expression for variables such as fat depot, medication, disease and menses status. Finally, the identification of adipose tissue proteins will allow the development of a much-needed database for human adipose tissue. The analysis of the effects of different variables on protein expression suggested a structural difference as well as an increase in inflammatory markers and an overall greater cellular activity in the omental compared to the subcutaneous adipose tissue depot; an increase in inflammatory markers in the omental adipose depot of obese patients compared to normal weight patients, differences in protein expression in pre- compared to menopausal and post-menopausal patients; and subtle changes in protein expression in adipose tissue in relation to cancer state, although the omental depot displayed a greater number of changes, indicating that endometrial cancer has a greater effect on this depot than the subcutaneous depot. Even at this early stage in the application of 2DE to human adipose tissue, positive results and identification of changes in protein expression in relation to disease and medication have been achieved. With a more extensive use of narrow range IPG gels, protein enrichment methods and fluorescent dyes are promising for the identification and development of a human adipose tissue database and the identification of biomarkers for the detection of disease and development of therapeutic targets.