In their paper, the researchers identify the pathway as "a master switch and central regulator" of the body's immune system, so just simply turning it off would be disastrous. The challenge is to come up with a way, possibly medication or genetic engineering, to keep the pathway alive for the immune system, but keep it dormant in the hypothalamus, where apparently all it does is cause trouble. That could take years, of course, even assuming the basic findings are born out by further research.
The research indicates that the critical signaling function of two hormones, insulin and leptin, is disrupted when the pathway in the hypothalamus is activated.
"Insulin is a hormone secreted by the pancreas, and leptin is another type of hormone secreted by fat tissue," Cai said. "When we have obtained enough calories, these two hormones travel to the brain and tell the hypothalamus it's time to stop eating, you have enough calories.
"But these two message systems can be interrupted by the activation of the pathway we've discovered, so the appetite doesn't shut down," he said.
It's also likely that the message telling the brain to increase energy expenditure is also shut down, Cai said. So, instead of going out and walking off those excess calories, the dieter takes a nap.
That plunges the person into a downward spiral, eating more and more, and putting on more and more pounds. The sentinels that are supposed to maintain the correct balance between caloric consumption and energy expenditure remain silent, deactivated by the reactivation of a part of the brain that shouldn't be there.
"Our work marks an initial attempt to study whether inhibiting an innate immune pathway in the hypothalamus could help to calibrate the set point of nutritional balance and therefore aid in counteracting energy imbalance and diseases induced by over-nutrition," the report states.
In other words, maybe there's a way here to reset the appetite and make it a lot easier to knock off those extra pounds. The research also suggests that in some cases, there's more at work than simply a lack of willpower when it comes to losing weight.