here hasn’t been a lot of innovation in the obesity drug market. Sure, a smattering of companies have come out with weight loss medications — but their results have been middling and their financial performance poor.
But new research from the Massachusetts Institute of Technology might help researchers pick a new target for obesity drugs. Scientists have found that glial cells — long thought to simply serve as supportive foil for neurons — play a role in appetite and feeding. Here’s what they’re doing:
In mice, the scientists have engineered astrocytes — a type of glial cell — that produce a surface receptor that binds to a chemical compound called CNO, which is similar to the drug clozapine. Giving the mice CNO turns on astrocyte activity — and makes them gorge on food. The work was just published in the journal eLife.
STAT chatted with MIT neuroscientist Guoping Feng about how controlling mice feeding patterns might ultimately be translated into a new (human) drug:
So what are you learning about glial cells, as they relate to obesity?
We’re seeing that glial cells very actively participate in direct neuronal function — particularly in the brain areas that control appetite, energy and metabolism.
Our goal was to see if we could control appetite and metabolic state by directly manipulating the glial cells. And we found that, in doing this, we can increase the mouse feeding. And if we silence or suppress the glial cells, we can reduce feeding.
Do you think a drug could be developed that modulates glial cell activity — and could help people control what they eat?
This is an exciting new direction and could lead to new drugs — but we’re in the very early stages still. We still don’t have an endogenous way to modulate the glial cells — that is, we don’t have a compound yet that can specifically activate or turn them on and off. So we don’t have a target yet, even in mice. And humans are very different than mice.
In a future study, we’re going to focus on what kinds of genes are expressed in the glial cells specifically — and we think we can use that information to develop a real drug target.
I don’t think there’s a very clear pathological understanding of the causes of obesity. So I do think that looking for a functional defect in glial cells, and their link to obesity, is a very important topic.