Endocrine Role of Adipose Tissue in Obesity and Related Disorders

Adipose tissue is a complex network of connective tissue constituting many cells types. It is a tissue whose role was assumed to be limited to storage and metabolism of energy and insulation. However the discovery of leptin followed by further elucidation of numerous hormones and factors secreted by adipose tissue and roles in metabolism and cell regulation it is regarded as an endocrine organ. Adipose tissue regulates the energy balance being influenced by either ligand-mediated transcription factors (C/EBP, PPARγ, RXR) or with other types of transcription factors with the secretion of several different signalling molecules (adiponectin, leptin etc.). The receptors are expressed onto different organs. Thus, these signalling molecules are involved in multiple function of the body. While there is a break of the regulatory discipline of adipogenesis, the subject becomes obese. Due to these phenomenal changes, fat cross the site of adipose tissue to get accumulated in non-adipose multiple tissues of different organs which finally results fat-associated toxic environment consequently leading to lipotoxicity; erratic glucose and fat metabolism in different organs. Energy regulation by the endocrine adipose tissue therefore has so far been identified as the key factor to combat obesity and associated diseases.