On this episode of Lifespan News, Emmett Short focuses on a recently published paper in which senescent cells tear off portions of their membranes, leaving them attached to other cells.
Script
Senescent cells and dad jokes are both hallmarks of aging. They’re outdated, irritating and both make you die a little inside. But new research has given scientists fresh insight that could help us fight back against these destructive relics. Well, senescent cells. Yeah, there’s been very little progress on dad jokes.
Welcome to lifespan news. I’m Emmett Short. Today we’re talking about new Research into senescent cells that found they can adhere to neighboring cells, eventually ripping apart and leaving fragments of themselves inside their victims. Reminds me of an ex-girlfriend. Anyway, learning how they work could help us figure out the relationship between senescent cells and cancer.
Cellular senescence is central to aging. That’s actually the sentence I use to do a mic check. “Cellular Senescence is central… we’re good? Ok.”
These are like old cells hanging out at the party that keep saying inflammatory things and they just won’t leave. There’s a lot more to it than that. For a great breakdown of these Zombie Cells, definitely check out this video from Lifespan.io’s Life Noggin channel created with the support of the SENS Research Foundation.
So, in this new preprint study, scientists marked 1 out of every 1000 cells with a fluorescent protein. In group one, the fluorescent cells were senescent. In the second group, it was the opposite. In the third group, all cells were senescent, and, finally, the control group contained only healthy cells.
What they found was pretty amazing. After a few days, tiny fluorescent dots started to appear. The cells were already tiny but these new dots were even tinier, and they turned out to be cellular fragments attached to the membranes of other cells. Time-lapses showed how the cells moved around and bumped into each other. Contacts between non-senescent cells were brief and ended without damaging either cell but, if at least one of the cells was senescent, they sometimes bonded together. Then as the cells eventually moved apart, the senescent cell was torn, leaving a part of itself attached to the other cell as you can see in this actual video taken with a microscope.
The fragments began appearing just 3 days after the induction of senescence, and by day 4, there were an average of 10-12 fragments per senescent cell. It’s like they sweat super glue and keep bumping into things. It’s not ideal. Making things worse the fragments exhibited “spinning, projecting and retracting arms, or crawling-like behavior”. Yikes! It’s like walking dead inside your body.
The researchers also wanted to see what effects the fragments have on the cells. Adding these fragments to liver cancer cells increased their growth rate. In 3D culture, cancer cells with the fragments became more active, invading the gel and forming branches. Which is super scary but at least we understand it better now which gets us one step closer to figuring out how to control it.
Now, I know I framed senescent cells in a pretty bad light here, but this is not the whole story. You may be thinking senescent cells bad. Maybe you want to cancel senescent cells from your bodies. But, Just like most things in life it’s a little more nuanced than that. There have been other studies that have demonstrated some benefits of senescence. So even down to the cellular level there’s good and evil in all of us and we’re going to need more information before we know how we should respond and when we get that information we’re not going to keep it to ourselves. We’ll make a video right away. So subscribe and click the bell so you don’t miss out. I’m Emmett Short, and we’ll see you next time on Lifespan News!
