To most it feels like the very second they begin a diet they immediately crave all those foods that are on the definite no go list. Hiroshima University researchers have confirmed there is a protein in the body that releases to regulate energy levels and can make you feel hungry when calorie intake has been restricted, regardless of brick house solid will power.
The hormone leptin reduces appetite, while ghrelin makes you want to eat more; these hormones activate neurons in the hypothalamus that control body energy. Professor Kazuyoshi Ukena suggests that the process is more complicated, confirming neuron exciting NPGL proteins increases appetite during fasting periods and decreases when full; basically the body has designed a way to regulate appetite to maintain weight at a constant level.
Ukena became curious of how metabolism is regulated after observing chickens grow larger irrespective of how much they were fed; after investigating and determining the birds possed NPGL to regulate energy metabolism further investigation found the molecule is present in all vertebrates including humans.
To examine the role of NPGL in mammals three groups of mice were fed three different diets to see if how what they ate affected NPGL levels: 1st group was fed a low calorie diet for one day; the 2nd group was fed a high fat diet for five weeks; and the 3rd group was fed high fat diets for 13 weeks. Animals on low calorie diets were found to experience extreme increases in NPGL expression; the 5 week group saw a large decrease in NPGL expression. Analysis found mice possess NPGL and the associated neuron network in the exact regions known to control appetite suppression and energy use.
NPGL is proposed to play key roles in the mechanisms of increasing appetite when energy levels fall, and reducing when energy overload is detected to keep the body at a healthy, functioning weight and alive, according to Ukena.
NPGL was concluded to promote appetite and work against hormones that suppress appetite. NPGL was injected directly into mice to confirm the hypothesis, and was found to immediately increase the animals appetite dramatically. Additionally animals whose NPGL levels dropped dramatically on the 5 week high fat diet were observed to have returned to normal after being fed the high fat diet for a longer period.
The team hope to conduct further studies into interactions of previously known appetite mechanisms with NPGL to learn more about appetite, metabolism, and body weight.
