Ghrelin and Obesity

My mom is always taking the most interesting classes. The current class she's taking is on neuroscience, I think. Every week she calls me with new information on subjects like the brain, obesity, memory and behavior. A recent class focused on a newly discovered hormone, ghrelin, and what it can do. Ghreline is a hormone produced in the fundus of the stomach and epsilon cells of the pancreas that stimulates hunger. Ghrelin levels increase before meals and decrease after meals. It is considered the counterpart of the hormone leptin. Ghrelin is also produced in the hypothalmic arcuate nucleus, where it stimulates the secretaion of growth hormone from the anterior pituitary gland. The discovery of ghrelin was reported in 1999, so scientists are just now learning about its role in growth, learning, depression, sleep and obesity. Scientists have learned that in fetuses, grehlin is early produced by the lung and promotes growth. Grehlin may enter the hippocampus from the bloodstream and play a role in enhancing learning and memory. It is suggested that learning may be best during the day and when the stomach is empty, since ghrelin levels are higher at that time. A 2008 study suggests that ghrelin might help defend against symptoms of stress-induced depression and anxiety. Also, short sleep duration is associated with high levels of ghrelin and obesity. As the hours of sleep increase, ghrelin concentrations were considerably lower, thereby potentially reducing appetite and avoiding potential obesity. The discovery of ghrelin is relatively new, but what they have discovered so far is that it plays a significant role in obesity. Ghrelin is increased by stress and lack of sleep, and may lead to obesity. There is much more to be learned about this hormone and its role in the human body. The other hormone that my mom learned about during the same lecture, is cortisol. This is a hormone that we've know of for awhile, and there are many products on the market that claim to control your cortisol levels. I will give you more information on cortisol in another blog. For now, remember that ghrelin is a newly discovered hormone that can affect a wide range of human conditions, from learning and memory, to growth, to obesity.