WORMS - they're a must in the garden but not so great for the body... or so we thought?
The discovery of certain genes in roundworms could lead to a breakthrough in the treatment of obesity.
Monash University and Danish researchers have found a gene in the worm that triggers a feeling of fullness as well as a need to sleep after eating. A similar gene is found in people.
The gene controls signals from the brain to the intestines.
The discovery opens up the opportunity to develop a drug that would reduce appetite and increase the desire to exercise.
Roger Pocock of the Monash Biomedicine Discovery Institute said when the intestines had stored enough fat, the brain would receive a message to stop moving - effectively putting the worm to sleep.
"When animals are malnourished they seek out food by roaming their environment," Associate Professor Pocock said. "When they're well fed they have no need to roam and when they're fully sated they enter a sleep-like state."
The researchers studied the roundworm because of the relative simplicity of its brain - it has just 302 neurons and 8000 synapses, or neuron-to neuron-connections, all of which has been mapped. Compare this with the human brain, which has billions of neurons, more than 160,000 kilometres of biological wiring and 100 trillion synapses.
Associate Professor Pocock said roundworms and humans shared up to 90 per cent of their genes as well as around half of all the known genes involved in human diseases.
The scientists discovered that different diets elicited different responses in roundworms. When fed low quality food the worms roamed in search of better nutrition.
The family of genes they researched has been previously 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," Associate Professor Pocock said.