Researchers at the University of Warwick have for the first time been able to detail how and why specific neurons in the brain control the hunger response. They have revealed a set of pacemaker nerve cells in the brain that appear to underlie the drive to feed which itself feeds on a complex web of signals. The level of complexity they have found is such that the system could be much more at risk of serious repercussions from a single error in how those signals are processed than anyone had previously thought. Any number of a range of errors could lead to over activity of these pacemaker cells and explain why many people find difficulty in eating less.
In the research, published in the May Issue of Nature Neuroscience, Dr David Spanswick and his research team in the University of Warwick’s Department of Biological Sciences, looked at a part of the brain called the hypothalamic arcuate nucleus which was known to deal with hunger and satiety signals but how it achieves this is poorly understood. The University of Warwick team have identified very specific neurons that act as feeding “pacemakers”.
This specific group of neurons- which they have dubbed the “ARC pacemaker” produce regular bursts of electrical activity. However these cells integrate and process a wide variety of signals indicating the energy needs of the body signals most often transmitted by the use of chemical messengers such as hormones like ghrelin, released from the gut and leptin from fat cells. The combination of these signals and their integration by the ARC pacemaker is such a finely balanced mechanism that one small error or mutation leading to any inappropriate communication in these pathways could produce a significant untoward affect on human eating or feeding patterns.