A gene in roundworms tells the brain to stop eating and when exercise is needed, researchers have found. The gene is similar to one found in humans and could be used to help break the cycle of overeating by triggering a feeling of being full.
The findings by Australian and Danish researchers could lead to a drug to combat obesity by reducing appetite and increasing the desire for exercise. The study discovered a gene-encoding protein called ETS-5, which controls signals from the brain to the intestines.
Associate Professor Roger Pocock, at Melbourne’s Monash University , said when the intestine had stored enough fat the brain would receive the message to stop moving, effectively putting the worm to sleep. Professor Pocock, of the university’s Biomedicine Discovery Institute, said: “When animals are malnourished, they seek out food by roaming their environment. When they’re well fed, they have no need to roam, and when they’re fully sated, they enter a sleep-like state.”
Researchers used the roundworm, which can infest the human gut, because of the comparative simplicity of its brain. It has just 302 neurons and 8,000 synapses, or neuron-to-neuron connections, all of which have been mapped. A human brain by contrast has billions of neurons, more than 160,000 kilometres of biological wiring, and 100 trillion synapses. Prof Pocock said the roundworm shared up to 80 per cent of their genes with humans, as well as around half of all the known genes involved in human diseases.
Prof Pocock said the discovery of ETS-5 is the first time a gene regulatory molecule of this type has been implicated in the brain-intestinal control of eating and activity. He said: “The ETS family of genes is present in humans and has previously been linked to obesity regulation. Now that we’ve learned this gene family controls food intake through a feedback system to the brain, it represents a credible drug target for the treatment of obesity.”
The study was published in the Proceedings of the National Academy of Sciences.
Source: The Mirror UK