Embryonic stem cells seem like they’re almost too good to be true. They come from developing embryos, where a somewhat blah stem cell just like all the others will end up surrounded by any other type of cells. There, the stem cell actually transforms into the same type of cell as those other cells.
All this type of stem cell needs to become any type of cell is to be planted in that environment. Here, chemical signals are read and interpreted by the little program inside the stem cell, where the transformation process can begin.
I was reminded of this incredible phenomenon when I learned about how and why a drug like semaglutide can have such a profound effect on so many different biological processes. You might not know the name, but you’ve almost certainly heard of the brand name drugs Ozempic and Wegovy, which use semaglutide for diabetes and weight loss, respectively.
Now, diabetes and weight loss are often closely related. A diet with too much sugar is a common cause of type 2 diabetes, and it’s also strongly correlated with a dangerously unhealthy weight gain. It’s not too wild to imagine some kind of correlation between a drug that causes weight loss, and a cousin-drug that helps to prevent diabetes.
What was surprising to me was to discover that semaglutide is also being studied for use in less obviously connected areas. There is some speculation that the drug could work to reduce the risk for dementia, and there is an indication that liver health can be dramatically affected by reducing inflammation.
Why should a drug designed for weight loss work on brain or liver health?!?
Maybe the most surprising potential benefit has been a reduction in addictive tendencies. The very idea that a drug that works to prevent or manage diabetes might also help with someone’s addiction, especially substance-based? That’s pretty wild.
I grew up in an era where people around me tried to quit smoking, then tried again a few months later, and so on. Quitting smoking during the 80s and 90s was really, really tough for folks, and it was becoming a health imperative by the early 2000s. I saw first-hand how powerful this addiction was.
It seems really counterintuitive that a drug designed to deal with helping you lose weight might also help with your opioid addiction, but that’s the world of GLP-1 agonist drugs like semaglutide. If we want to understand why some perceived wonder drug can act on so many seemingly different processes in our bodies, we need to understand what a GLP-1 receptor is.
Let me explain this by way of comparison to what happens inside your nose whenever you smell something.
But the real magic happens deeper within, in a specialized tissue called the olfactory epithelium. About six million tiny receptor cells (in humans) act as docking stations, waiting for the right molecules. Each of these receptors is like a bouncer at a club: only a certain type can get in.
As soon as this connection is made, an electrical signal goes to the brain. The connecting molecules complete a circuit of sorts, and ions flow from the olfactory cell to the temporal lobe, the part of your brain that sits behind and under your ears.
If the signal matches a stored memory, you will recognize the odor.
While only your nose has these little odor receptors, GLP-1 receptors can be found in lots of important organs and systems in your body.
Your pancreas is where the amount of sugar in your blood is regulated. If there’s too much sugar detected by specialized beta cells in there, insulin will be secreted more effectively into the bloodstream.
In the brain, things don’t operate all that differently at the GLP-1 receptor level. Those same little gatekeepers are always on the prowl for a signal to act, and when they connect with a particular hormone, it’s like seeing the Bat-signal up in the sky: it’s time to act.
You can find GLP-1 receptors in your hypothalamus, where you decide (at a subconscious level) whether or not to feel hungry. You can also find them at your brain stem, where signals from your gut are intercepted and interpreted by little gatekeepers, ready to let you know you’re full now and can stop eating.
What’s really interesting to me is that they’re also in the hippocampus, where memories are formed, among other things. If it seems odd that both dementia and a gambling addiction might be addressed by the same drug, these omnipresent GLP-1 receptors are the reasons why.
Nature doesn’t usually like to reinvent the wheel, so to speak. If something in your body does one job, it’s not all that uncommon to discover that they’re also doing other jobs within your body.
There’s plenty of promise from this new class of drugs, but there’s also plenty of uncertainty surrounding longer term impacts of GLP-1 agonist drugs. Time will ultimately have to inform us as to whether the current mad rash to prescribe and sell these drugs is wise.
Have you ever been prescribed semaglutide? Do you know much more about how the drug operates? Please share any relevant experiences:
Yes, I have been prescribed several different GLP-1s. Mounjaro worked great, but wasn't covered by insurance at $1k+. That will eventually change, but the delay in getting these drugs will take years off the lives of those who benefit from them. In the meantime, I'm taking a cheaper drug that is less effective but works over time. It feels like I'm racing against the clock.
I am a diabetic and used Victoza for a while. Great if you like burping rotten eggs from undigested food hanging around in your belly. I finally made dietary changes and got off of it. Now I am 6'3" and 170 pounds down from 245. Perturbing complex systems is not advisable.