![]() Non-hypothalamic targets of leptin are referred to as peripheral targets. Location of action The central location of action ( effect) of the fat cell-specific hormone leptin is the hypothalamus, a part of the brain, which is a part of the central nervous system. In regard to the hormone leptin, central vs peripheral refers to the hypothalamic portion of the brain vs non-hypothalamic location of action of leptin direct vs indirect refers to whether there is no intermediary, or there is an intermediary in the mode of action of leptin and primary vs secondary is an arbitrary description of a particular function of leptin. In the context of its effects, the short describing words central, direct and primary are not used interchangeably. Predominantly, the "energy expenditure hormone" leptin is made by adipose cells, and is thus labeled fat cell-specific. Effects Ī comparison of a mouse unable to produce leptin, resulting in obesity, constant hunger, and lethargy (left), and an active normal weight mouse (right) In obesity, a decreased sensitivity to leptin occurs (similar to insulin resistance in type 2 diabetes), resulting in an inability to detect satiety despite high energy stores and high levels of leptin. Many of these additional functions are yet to be fully defined. Īlthough regulation of fat stores is deemed to be the primary function of leptin, it also plays a role in other physiological processes, as evidenced by its many sites of synthesis other than fat cells, and the many cell types beyond hypothalamic cells that have leptin receptors. These include cell receptors in the arcuate and ventromedial nuclei, as well as other parts of the hypothalamus and dopaminergic neurons of the ventral tegmental area, consequently mediating feeding. Leptin receptors are expressed by a variety of brain and peripheral cell types. High leptin levels are interpetred by the brain that energy reserves are high, whereas low leptin levels indicate that energy reserves are low, in in the process adapting the organism to starvation through a variety of metabolic, endocrine, neurobiochemical, and behavioral changes. The amount of circulating leptin correlates with the amount of energy reserves, mainly triglycerides stored in adipose tissue. Īs one of the major signals of energy status, leptin levels influence appetite, satiety, and motivated behaviors oriented towards the maintenance of energy reserves (e.g., feeding, foraging behaviors). Leptin (from Greek λεπτός leptos, "thin" or "light" or "small") is a hormone predominantly made by adipose cells and its primary role is likely to regulate long-term energy balance. Structure of the obese protein leptin-E100. positive regulation of cold-induced thermogenesis.regulation of lipid biosynthetic process.regulation of signaling receptor activity.positive regulation of tyrosine phosphorylation of STAT protein.tyrosine phosphorylation of STAT protein.positive regulation of tumor necrosis factor production.negative regulation of appetite by leptin-mediated signaling pathway.positive regulation of phosphatidylinositol 3-kinase signaling.regulation of lipoprotein lipid oxidation.positive regulation of cell population proliferation.positive regulation of fat cell apoptotic process.regulation of natural killer cell mediated cytotoxicity.regulation of nitric-oxide synthase activity.regulation of cytokine production involved in inflammatory response.positive regulation of cytokine production.regulation of natural killer cell proliferation.positive regulation of luteinizing hormone secretion.positive regulation of receptor signaling pathway via JAK-STAT.positive regulation of insulin receptor signaling pathway.regulation of protein localization to nucleus.negative regulation of transcription by RNA polymerase II.positive regulation of follicle-stimulating hormone secretion.negative regulation of apoptotic process.negative regulation of glutamine transport.negative regulation of cartilage development.activation of protein kinase C activity. ![]() regulation of brown fat cell differentiation.positive regulation of protein import into nucleus.positive regulation of T cell proliferation.bone mineralization involved in bone maturation.regulation of natural killer cell activation.regulation of steroid biosynthetic process.negative regulation of vasoconstriction.negative regulation of metabolic process.positive regulation of protein kinase B signaling.regulation of endothelial cell proliferation.positive regulation of hepatic stellate cell activation.positive regulation of peroxisome proliferator activated receptor signaling pathway. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |