An Indian-origin scientist gives an answer to the most sought after question of obese dieters, "Why it is so frustratingly difficult to stick to a diet?"
When we don't eat, hunger-inducing neurons in the brain start eating bits of themselves. That act of self-cannibalism turns up a hunger signal to prompt eating, according to Rajat Singh of Albert Einstein College of Medicine.
"A pathway that is really important for every cell to turn over components in a kind of housekeeping process is also required to regulate appetite," said Singh.
The cellular process uncovered in neurons of the brain's hypothalamus is known as autophagy (literally self-eating.)
Singh says the new findings in mice suggest that treatments aimed at blocking autophagy may prove useful as hunger-fighting weapons in the war against obesity.
The new evidence shows that lipids within the so-called agouti-related peptide (AgRP) neurons are mobilized following autophagy, generating free fatty acids.
Those fatty acids in turn boost levels of AgRP, itself a hunger signal.
When autophagy is blocked in AgRP neurons, AgRP levels stop rising in response to starvation, the researchers show.
The study was reported in the August issue of the Cell Press journal Cell Metabolism.