Researchers have discovered how an immune system molecule hijacks a brain circuit and reduces appetite when you are inflicted with an illness.While loss of appetite during illness is common, it contributes to reducing a patient's strength and in cancer patients, it can even shorten lifespan.The new research points to potential targets for treating loss of appetite and restoring a patient's strength."Treating loss of appetite won't cure an underlying disease, but it could help a patient cope," said senior author of the study Bruno Conti, professor at The Scripps Research Institute (TSRI) in California, US."Many times, loss of appetite can compromise clinical outcome. A weak individual is less likely to be able to cope with chemotherapy, for instance," Conti said.
Many people recover their appetite after illness. But in patients with diseases such as cancer or AIDS, loss of appetite can turn into a wasting disease called cachexia, also known as "the last illness" because it can accelerate a patient's decline.The findings were published in The Journal of Neuroscience.The researchers believe the circuit affected by an immune molecule called interleukin 18 (IL-18) may be a potential drug target for treating loss of appetite, and possibly support weight loss for those with metabolic disorders."IL-18 regulates feeding by locking directly into the neuronal circuitry," Conti said.