IL-6, a multifunctional cytokine, has been shown to alter insulin sensitivity both in vivo and in vitro studies. Resistin, has been shown to target key nodes of the insulin signaling pathway to induce insulin desensitization. Adiponectin acts as an insulin-sensitizer and a target of anti-diabetic drugs, leptin has been shown to reverse insulin resistance. This vast organ is capable of regulating many physiological processes by the secretion of adipokines like adiponectin, leptin, resistin, TNF-α, and IL-6. ![]() Researches provide strong evidence that adipose tissue plays important roles as an endocrine organ. 19 IL-6 has been shown to activate SOCS-1 and -3 proteins in the liver, thus accompanying insulin resistance. 18 T2DM shows elevated circulating levels of Interleukins and IL-6 is one among them. IL-6 is a multifunctional cytokine that plays numerous roles in addition to controlling immune cell function, such as behaving as a hepatocyte-stimulating factor and a growth factor for metastatic cells. 16 Exposure to higher glucose concentrations significantly increased resistin expression in 3T3-L1 adipocytes, while treatment with insulin reduced it. Resistin was shown to be highly expressed among obese cases. Resistin was latest adipokine to be discovered in the year 2001, resistin (RETN) genes helps in adipocyte differentiation, these were down regulated in mature adipocytes during exposure to Thiazolidinediones (TZD). 14 Leptin polymorphism has a role in hypertension. Leptin has been proven to increase with increasing adiposity among humans and rodents. Obesity is not only influenced by lack of leptin but also leptin resistance. ![]() 13 Diet and leptin treatment is explored as a method of diabetes control. 12 Its levels are estimated to be higher in persons with diabetes mellitus. Genetic defects in anorexigenic pathway can cause obesity, such as mutations in the melanocortin-4 or leptin receptors. 11 The availability of adiponectin might reverse insulin resistance and therefore lead to decrease the risk of diabetes. 10 Adiponectin could suppress glucose production and increase insulin sensitivity. 8, 9 Adiponectin promotes an insulin-sensitizing effect. Hypoadiponectinemia correlates with the development of insulin resistance and type 2 diabetes. Increase in body mass index leads to insulin resistance and type 2 diabetes. Main bodyĪdiponectin is an adipocyte-specific hormone known to be involved in a variety of metabolic, anti-inflammatory, and vasoprotective functions. In this mini review, we will briefly highlight roles of various adipokines (adiponectin, leptin, resistin, TNF-α, and IL-6) in regulating insulin sensitivity and resistance. Interestingly, recent research provides increasing evidence of the importance of regulating adipocyte function, adipose tissue metabolism and inflammation. 8 Several extracellular factors cause obesity, related adipocyte metabolism and macrophage infiltration. 6, 7 Adipokines have a great potential for clinical use as potential therapeutics for obesity, obesity related metabolic, cardiovascular and other diseases. 5 Their role in causing insulin resistance via various mechanisms involving the flux of in pro-oxidant and antioxidant state has been seen. 4 These adipocytokines can act as key regulators of response to insulin in peripheral tissues. 4 This chronic low-grade inflammation causes increase in macrophage infiltration, leads to increased adipocyte secretion of pro-inflammatory molecules such as resistin, tumor necrosis factor- Alpha, and interleukin-6(IL-6). The release of these cytokines causes a chronic sub inflammatory state that could play a central role in the development of insulin resistance and type 2 diabetes, and the increased risk of cardiovascular disease associated with obesity, together referred as metabolic syndrome. These adipokines helps in the regulation of hemostasis, blood pressure, lipid and glucose metabolism, inflammation, and atherosclerosis. Adipose tissue secretes variety of products known as ‘adipokines’, including leptin, adiponectin, resistin and visfatin, as well as cytokines and chemokines such as tumor necrosis factor- Alpha (TNF-α), interleukin-6 and monocyte chemoattractant protein-1. Due to the dramatic rise in obesity and its metabolic sequelae during the past decades, adipose tissue gained tremendous scientific interest. ![]() Adipose tissue - composed of adipocytes, fibroblasts, immune cells, and various other cell types, once known as passive reservoir is now considered an endocrine organ secreting bioactive molecules including hormones now termed adipokines with various known and unknown endocrine functions in addition to regulating fat mass and nutrient homeostasis.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |