Year: 2009
Type: article
Abstract: Adipose tissue may be regarded as the biggest "endocrine gland" in the human body. Number of well-known adipokines (hormones of adipose tissue) have been increasing rapidly during the last years. In many studies, included ours, increased secretion of adipokines such as: TNF-α, IL-6, leptin and resistin and decreased secretion of adiponectin in obesity have been linked with development of insulin resistance. In the last five years new adipokines such as: visfatin, vaspin, omentin and retinol binding protein-4 (RBP-4) have been described. This review summaries the current literature and presents the up to date knowledge concerning the role of new adipokines in the development of insulin resistance. Serum concentration of visfatin increases in obesity and experimental studies revealed its insulinmimetic action. In metabolic syndrome decreased visfatin/insulin index was observed. Vaspin is a serine protease secreted by adipose tissue in increased amount in obesity. Experimental studies revealed that vaspin improves glucose tolerance and insulin sensitivity in mice. Omentin is produced and secreted by stromal cells of adipose tissue but not by adipocytes. Its secretion is decreased in obesity. Omentin increases insulin-stimulated transmembrane transport of glucose and fosforylation of Akt in adipocytes. It suggests that omentin increases insulin sensitivity. Retinol binding protein 4 (RBP-4) is a protein secreted by adipose tissue in increased amount in obesity. Experimental studies revealed that RBP-4 participated in the development of insulin resistance in liver and muscular tissue. In summary, regardless of increasing number of experimental data concerning substances secreted by adipose tissue, involved in the development of insulin resistance, there are still many uncertainness of their role in the pathogenesis of this often disturbance in humans.
Source: Via Medica Journals
Authors: Magdalena Olszanecka‐Glinianowicz, Piotr Kocełak, Bartłomiej Orlik, Gabriela Handzlik, Łukasz Juszczyk
Institution: Medical University of Silesia
Language: Polish
Subfield: Endocrinology, Diabetes and Metabolism
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W1845487560