HISTOLOGY AND HISTOPATHOLOGY

Cellular and Molecular Biology

 

Review

Role of extracellular matrix remodelling in adipose tissue pathophysiology. Relevance in the development of obesity

Victoria Catalán1,2, Javier Gómez-Ambrosi1,2, Amaia Rodríguez1,2 and Gema Frühbeck1,2,3*

1Metabolic Research Laboratory, Clínica Universidad de Navarra, Pamplona, Spain, 2CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Spain and 3Department of Endocrinology and Nutrition, Clínica Universidad de Navarra, Pamplona, Spain.

Offprint requests to: Victoria Catalán, PhD, Metabolic Research Laboratory, Clínica Universidad de Navarra, Avda. Pío XII, 36, 31008 Pamplona, Spain. e-mail: vcatalan@unav.es


Summary. Adipose tissue responds dynamically to alterations in nutrient excess through adipocyte hypertrophy and hyperplasia, followed by increased angiogenesis, immune cell infiltration, extracellular matrix (ECM) overproduction, and thus, increased production of proinflammatory adipokines during the progression of chronic inflammation. Adipose tissue remodelling is an ongoing process that is pathologically accelerated in the obese state in large part mediated by ECM proteins and proteases. The ECM is subject to major modifications by adipocytes and other cell types that are infiltrated in the adipose tissue, such as macrophages and vascular cells. In obesity, unusual expression of ECM components and fragments derived from tissue-remodelling processes can influence immune cell recruitment and activation, actively contributing to inflammation. ECM turnover requires a tightly regulated balance between the synthesis of the components and their proteolysis, mainly by fibrinolytic systems and matrix metalloproteases (MMPs). In this review, we discuss the key cellular steps that lead to adipose tissue remodelling and the main molecular mechanisms and mediators in this process. We highlight the importance of hypoxia and angiogenesis in the adipose remodelling process, as well as the cross-talk between adipocytes, macrophages and ECM components
. Histol Histopathol 27, 1515-1528 (2012)

Key words: Adipose tissue, Extracellular matrix, Angiogenesis, Hypoxia, Collagens, Metalloproteinases

DOI: 10.14670/HH-27.1515