The modern-day quest for the fountain of youth is decidedly more scientific than the one that inspired Ponce de Leon to set sail for Florida all those years ago. Instead of looking for magical waters that can reverse aging and disease, scientists today are taking their search to the lab.
What are these 21st century explorers looking for? A common denominator at the root of all the different ways our bodies deteriorate as we age. And some think they may have found it in something called senescent.
But what exactly are senescent cells? Put simply, they’re old, tired cells that have given up on life. As a result of years of stress and damage, they’ve stopped functioning the way normal cells do. They no longer take part in the healthy cell cycle of replicating themselves and creating new, healthy cells. They hang around doing nothing useful. Instead, they secrete inflammatory compounds that damage surrounding cells.
In short, they’re curmudgeonly old cells, and they’re intent on bringing your other cells down with them. Which is why they’re implicated in everything from general aging to development and progression of chronic diseases like cancer.
That’s also why they’re a prime target of anti-aging research. And one of the ways researchers are fighting against senescent cells is with a class of drugs called senolytics. These drugs cause senescent cells to die off by disabling the pathways that keep them alive despite the damaging, inflammatory environment they create. The result, at least in preliminary studies, is that age-related diseases can be delayed or even alleviated.
So, is this it? Have we finally found the fabled fountain of youth? Are senolytics the answer to all that ails us?
Not quite. Unfortunately, pharmaceutical senolytics — many of which are cancer drugs — tend to be toxic not only to the senescent cells, but also to the healthy cells around them. Which leaves researchers looking for alternatives that are less toxic but have the same positive effects.
The good news is they didn’t have to look any farther than the supermarket shelves. That’s because there’s a compound in a number of fruits that is showing promise in destroying senescent cells while leaving healthy cells unscathed.
The garden of youth
That compound is called fisetin, a naturally occurring flavone found in high concentrations in strawberries. It also occurs in lesser amounts in other fruits and vegetables, including apples, persimmon, grapes, onions, and cucumbers. Fisetin is also widely available as a nutritional supplement, and it has none of the side effects of the pharmaceutical senolytics.
Initial studies on fisetin are making researchers hopeful that they may be at the beginning stages of finding an answer to countless age- and disease-related problems.
So far, all the studies that have been conducted on fisetin have been in petri dishes or in animals, so remember that this is all preliminary. But still, it’s exciting to see what impressive effects it’s having.
For instance, in one in vitro study researchers found that fisetin reduced both the viability and the numbers of senescent cells, while leaving the healthy cells alone. What’s more, it’s able to penetrate cell membranes to get right into the cells. Once in there, fisetin exerts antioxidant effects.
Other research has found that in addition to being an antioxidant, fisetin may fight against high blood sugar, high cholesterol, inflammation, and even cancer.
Here are just a few of the most promising areas of research into fisetin …
The secret to fisetin’s fountain-of-youth effects
Free radical damage has been linked to numerous diseases — many of them age-related. Diabetes, retinal degeneration, Alzheimer’s, cancer, and more all have ties to free radical damage. Antioxidants counter the effects of free radicals, which is why they’ve been the focus of lots of research over the years. Fisetin has been shown to protect against oxidation and increase levels of the antioxidant glutathione within cells.
Fisetin the cancer fighter
One of the most promising areas of research for fisetin is in cancer protection. Studies in cells and in animals suggest that fisetin may prevent cells from spreading in several types of cancer. In addition, it seems to inhibit tumor growth by reducing angiogenesis — the process that allows blood vessels to form and feed tumors. Other studies have shown fisetin to cause cancer cells to die off. And only the cancer cells were targeted. Normal cells were much less affected.
Fisetin is being investigated in a few specific types of cancer:
- Lung cancer. One of the most common types of cancer in the world, lung cancer is to blame for nine out of ten cancer-related deaths (and no, they’re not all smoking-related). So finding ways to treat lung cancer is an important goal of medical research. Initial studies suggest that fisetin might decrease lung tumor volume and prevent lung cells from spreading.
- Colon cancer. Colon cancer rates are on the rise, most notably in young people. Diet has been shown to be an important factor in colon cancer, and flavonoids are one promising area of research. When tested on colon cancer cells, fisetin caused cell death and inhibited growth. Again, this is only in lab tests, not humans. So the results are preliminary — but promising.
- Prostate cancer. Fisetin may inhibit prostate cancer cell growth and cause cancerous cells to die off. Research also shows that normal prostate cells are unaffected by fisetin.
- Pancreatic cancer. This type of cancer is notoriously resistant to treatment, so researchers are constantly searching for promising alternatives. In very early studies fisetin seems to inhibit the growth and proliferation of pancreatic cancer cells, while also causing cancerous cells to die off. However, results haven’t been consistent, so more research is needed.
- Melanoma. Malignant melanoma, once it metastasizes, has no effective cure. Early studies of fisetin suggest it can decrease the viability of melanoma cells.
Brain protection straight from the berry patch
Brain health is one of the most common concerns people have as they get older. Free radical damage contributes to many age-related problems. In addition, oxidative stress is linked to arteriosclerosis, which can lead to stroke.
Because fisetin is a potent antioxidant — and because it also appears to affect a number of pathways involved in the health of neurons — researchers have been investigating whether it might offer some protection against stroke, cognitive decline, and other neurological ailments.
Here’s what they’ve found.
- Stroke. In animal studies, fisetin has been shown to offer some brain protection after stroke. It reduced behavioral deficits in rabbits who had suffered stroke, and it also appeared to protect brain injury in mice after they had an interruption in blood supply to the brain.
- Brain function. Fisetin appears to have a strong anti-inflammatory effect on brain cells. One study found that it may help long-term memory.
- Depression. One study looked at mouse models to test the effects of fisetin on depression. The tests showed that it appears to have antidepressant effects by regulating serotonin and noradrenaline levels. In addition, the depressed mice who received fisetin suffered less “immobility” time.
So far, so good…
So is fisetin the “fountain of youth” modern-day explorers have been looking for?
It’s far too soon to tell. No research has been conducted yet on humans, so no one knows whether the in vitro and animal studies that have been conducted so far will bear out. Still, the results are promising. And it’s always exciting to see an all-natural, plant-derived compound outperform toxic pharmaceuticals.
I’ll be keeping my eye on fisetin, and I’ll keep you posted as new research emerges. But in the meantime, adding more fisetin to your daily regimen certainly won’t hurt. You can get fisetin either from food sources (strawberries, onions, cucumbers), supplements (50-150 mg per day) — or both.
“New agents that that target senescent cells: The flavone, fisetin, and the BCL-XL inhibitors, A1331852 and A1155463,” Aging 2017; 9(3):1
“The Fountain of Youth by Targeting Senescent Cells?: Trends in Molecular Medicine 2017; 23(1): 6-17