Profile of adipose tissue gene expression in premenopausal and postmenopausal women: site-specific differences

Objectives: Menopause increases the risk of several pathologies, probably due to enlarged levels of visceral fat. Apart from morphological and endocrine changes, a cluster of genes, still not fully defined, may be involved in these alterations. The objectives of the present study, therefore, were to analyze differences in adipose tissue gene expression between premenopausal and postmenopausal women and to ascertain whether any differences were depot specific. Methods: Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) biopsies were taken from 7 premenopausal and 7 postmenopausal women undergoing surgery because of morbid obesity. RNA was extracted, and the overall gene expression profile was analyzed by microarray analysis. Results: In general, SAT genes were overexpressed, whereas VAT genes were down-regulated in premenopausal compared with postmenopausal women. We found 724 differentially expressed genes in SAT and 327 in VAT. These differences suggest that several biological processes, such as the immune system and other metabolic processes, were altered based on menopause status. Regarding individual genes, neurexin 3, metallothionein 1E, and keratyn 7 showed the most pronounced differences. Interestingly, the expression of these genes was related to body fat distribution. Conclusions: Our results reveal that menopause influences the adipose tissue expression of many genes, especially of neurexin 3, metallothionein 1E, and keratyn 7, which are associated with the alteration of several key biological processes, such as the immune system and cell metabolism. Gene expression in adipose tissue could be used for diagnosis and the development of new therapeutic strategies against obesity and related alterations, depending on menopause status.