Insulin and Insulin Receptors in Adipose Tissue Development

• Published in: International journal of molecular sciences Vol. 20; no. 3; p. 759
• Main Authors: Cignarelli, Angelo, Genchi, Valentina Annamaria, Perrini, Sebastio, Natalicchio, Annalisa, Laviola, Luigi, Giorgino, Francesco
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 11-02-2019; MDPI
• Subjects: adipocyte; Adipocytes; Adipogenesis; Adipose tissue; Adipose tissue (brown); Alternative splicing; Angiogenesis; Body fat; Body weight; Cell adhesion & migration; Cytokines; Diabetes; Endothelium; Fatty acids; Functional plasticity; Gene expression; Glucose; Insulin; insulin receptor; Insulin receptors; Insulin resistance; Insulin-like growth factors; Kinases; Lipids; Metabolism; Paracrine signalling; Physiology; Proteins; receptor isoform; Review; Stem cells; Transcription factors; adipose tissue; receptor isoform; insulin receptor; adipocyte
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms20030759

Insulin is a major endocrine hormone also involved in the regulation of energy and lipid metabolism via the activation of an intracellular signaling cascade involving the insulin receptor (INSR), insulin receptor substrate (IRS) proteins, phosphoinositol 3-kinase (PI3K) and protein kinase B (AKT). Specifically, insulin regulates several aspects of the development and function of adipose tissue and stimulates the differentiation program of adipose cells. Insulin can activate its responses in adipose tissue through two INSR splicing variants: INSR-A, which is predominantly expressed in mesenchymal and less-differentiated cells and mainly linked to cell proliferation, and INSR-B, which is more expressed in terminally differentiated cells and coupled to metabolic effects. Recent findings have revealed that different distributions of INSR and an altered INSR-A:INSR-B ratio may contribute to metabolic abnormalities during the onset of insulin resistance and the progression to type 2 diabetes. In this review, we discuss the role of insulin and the INSR in the development and endocrine activity of adipose tissue and the pharmacological implications for the management of obesity and type 2 diabetes.