- Ozempic just surprised scientists again.
Scientists thought Ozempic and other similar drugs, like Wegovy, helped people lose weight by working primarily in the gut.
But now it's looking like the drug's real power could be in the brain.
The active ingredient in the drugs is called semaglutide.
Semaglutide is a molecule meant to mimic the hormone GLP-1.
- GLP-1 is made in the intestine and is released in response to food entering the intestine.
It's also made in the brain, and so because of this, both your gut, as well as your brain, are wired to listen to this GLP-1 signal - Naturally produced GLP-1 in the gut degrades in a few minutes.
In that time, it gets the pancreas to produce insulin, which helps move sugar out of the bloodstream and into the body's cells.
This is why the drugs can be hugely beneficial for people with diabetes.
When it became clear that semaglutide also helped people lose weight, and lots of it, scientists thought what made it so effective was how it can work in the gut, slowing down digestion, and as a result, decreasing appetite.
But it looks like it's the semaglutide in your brain that really helps people eat less.
Unlike the natural GLP-1, semaglutide takes days to break down, so it has time to travel into the brain.
In the brain, it works not only as a hormone, but also as a neurotransmitter, a kind of molecule used by the nervous system to transmit messages throughout your body, including your brain.
- When you inject a drug like Ozempic, that drug lasts for many days.
So now it has an opportunity to travel to the brain and also target some of those, you know, molecules that are there to listen to the GLP-1 message in the brain.
- In the brain, semaglutide makes its way to the hypothalamus, a small region that acts as the body's control center.
Once there, it inhibits the neurons that promote hunger and stimulates the neurons that suppress appetite.
Semaglutide can also affect the reward system where the brain releases dopamine, a hormone that can control motivation, pleasure, and cravings.
The relationship between dopamine and semaglutide is not completely understood.
But one idea is that it works like this.
When you see a fast food restaurant off the side of the road, your brain produces a rush of dopamine because it thinks a reward is coming.
This rush increases the chances that you'll pull over and get yourself a treat.
But with semaglutide in the brain, (screen screeching) that dopamine rush, or craving, is reduced, making it less likely you'll stop to get something to eat.
Because semaglutide decreases cravings, this may be why people report a reduced interest in drinking, smoking, (screen whooshing) shopping, and other addictive and compulsive behaviors.
For now, Ozempic is only approved to help people with diabetes lower their blood sugar, and Wegovy is only approved to help people living with obesity, or some weight-related health issues.
- One in every three people taking semaglutide will be able to lose more than 20% of their body weight.
That is very, very good.
- Newer medications like Zepbound and Mounjaro combine molecules mimicking GLP-1 and other hormones to help people lose weight even more effectively.
There's still a lot to learn about how exactly these drugs work, what the long-term effects might be, and what else they might treat.
And since there are also GLP-1 receptors in parts of the brain that control emotions, (screen whooshing) memory, and even motor control.
- That gives us an opportunity to ask, "Why are they there?"
Right?
What are they doing?
And that can give us a clue as to what this drug could potentially be used for outside of metabolic disease.
When you have a drug that targets the brain, you really have to worry about what else is it gonna do that you're not really initially seeing.
(mysterious music)