14 DAY TRIAL // Researchers with Yale University in the US claim to have come one step closer to understanding and treating obesity in human patients, and that genetically engineered mice are partly to thank for it.
Writing in The Journal of Clinical Investigation, the specialists explain that, while trying to come up with a way to help people not pile up pounds up to the point when they become obese, they modified the brains of laboratory mice.
Specifically, they genetically engineered mice sporting neurons that were missing a receptor intended to regulate their activity. As detailed in said journal, the brain cells this study focused on are known as POMC neurons.
According to previous investigations, POMC neurons sit in a brain region dubbed the hypothalamus, and are in charge of regulating food intake. Specifically, evidence at hand indicates that, when activated, they curb appetite.
When a special receptor dubbed PPARgamma was removed from these neurons, they became more active than they would have normally been. This coincided with the mice's not putting on weight despite being fed a high-fat diet and lots of sugar.
By the looks of it, the laboratory rodents did not get fat despite being granted free access to fatty and sugary treats due to the fact that, once their PPARgamma receptors were deleted from their POMC neurons, they lost their appetite.
“When we blocked PPARgamma in these hypothalamic cells, we found an increased level of free radical formation in POMC neurons, and they were more active,” researcher Sabrina Diano explained in a statement, as cited in a press release on Yale University's website.
Furthermore, “These animals ate fat and sugar, and did not gain weight, while their control littermates did. We showed that the PPARgamma receptor in neurons that produce POMC could control responses to a high-fat diet without resulting in obesity.”
Specialist Sabrina Diano and fellow researchers argue that their discovery could not only help prevent obesity and the cases of diabetes caused by it, but also help folks who are diabetic but not yet obese not gain weight when trying to control their condition with the help of a class of drugs dubbed TZD.
Apparently, these drugs are known to cause people to put on weight. The Yale University scientists suspect that this is because they act on the brain and especially on this PPARgamma receptor. Hence, blocking their access to the brain altogether could help prevent obesity in diabetic patients.
“Our study suggests that the increased weight gain in diabetic patients treated with TZD could be due to the effect of this drug in the brain, therefore, targeting peripheral PPARgamma to treat type 2 diabetes should be done by developing TZD compounds that can’t penetrate the brain. We could keep the benefits of TZD without the side-effects of weight gain,” said Sabrina Diano.