Nav: Home

Researchers make old gut stem cells grow like young ones in a dish

March 14, 2017

Intestines experience a lot of wear and tear. Without the stalwart stem cells that live in our gut's lining, our ability to absorb food would dwindle and bacteria from the digestive tract would be able to breach the bloodstream. Unfortunately, the regenerative abilities of intestinal stem cells decline with age. However, it may be possible to partially reverse aging in gut stem cells, at least in a petri dish, researchers report in Cell Reports March 14.

"It looks like aging is not a one-way road, at least not for the intestine," says study co-author Hartmut Geiger of Cincinnati Children's Hospital.

Several chemical signals that are predominant in young intestinal stem cells were absent or downregulated in stem cells from older mice, but the researchers zeroed in on the Wnt protein. Wnt signals play a key role in directing stem cells during embryonic development, which led Geiger and colleagues to hypothesize that it might be helping to control stem cell growth and pluripotency in the gut later in life. Restoring Wnt signaling led to rejuvenation for intestinal stem cells from both mice and humans.

Aging in intestinal stem cells leads to changes in villi, the finger-shaped protuberances that line the small intestine and absorb nutrients, and crypts, the valleys between villi where the intestinal stem cells live. To assess the gut stem cells' villi-growing ability, the researchers chopped up samples from gut biopsies into tiny pieces.

"Only the pieces that have stem cells in them will reform part of this intestinal crypt structure when you put them in a petri dish," explains Geiger. "And then you can count how many crypts and villi are there and how complex they look." When the researchers added Wnt to petri dishes housing aged stem cells, those stem cells began growing crypts and villi in patterns resembling their younger counterparts.

When Geiger and his team compared biopsies of intestines from young mice (aged 2-3 months) to older mice (aged 20-22 months), they found that the older mice had fewer villi but that those villi were larger than those from young mice. "The overall architecture of the intestine is different upon aging, so you can clearly see aging-related changes intestinal architecture. That has not been reported in detail before," says Geiger.

It's still unclear what this change in gut architecture means for digestion and age-related gut health problems, but the changes likely affect intestines' ability to heal after wear and tear. Digesting each meal requires the gut to squeeze and stretch, which may damage some cells. And since the gut is also full of microbes, the intestinal lining cells are on the front lines, interacting with bacteria.

"Turnover in the gut is pretty fast. In 1-2 weeks, every cell is replaced by a new one. And why is that? Because it's a very aggressive environment in the intestine," says Geiger. "The turnover of aging stem cells is lower. So they do not make as quickly more differentiated cells as the young ones." Since intestinal stem cells are the only ones that can replace gut lining tissue, their aging affects the entire intestine.

However, the Wnt experiments suggest a promising direction for future research, says Geiger. Even though Wnt proteins are difficult to manipulate, their ability to reverse intestinal stem cell aging suggests a pathway that clinicians may eventually be able to target.
-end-
Work in the laboratory was supported by grants from the National Institutes of Health.

Cell Reports, Nalapareddy et al.: "Canonical Wnt Signaling Ameliorates Aging of Intestinal Stem Cells" http://www.cell.com/cell-reports/fulltext/S2211-1247(17)30254-1

Cell Reports (@CellReports), published by Cell Press, is a weekly open-access journal that publishes high-quality papers across the entire life sciences spectrum. The journal features reports, articles, and resources that provide new biological insights, are thought-provoking, and/or are examples of cutting-edge research. Visit: http://www.cell.com/cell-reports. To receive Cell Press media alerts, contact press@cell.com.

Cell Press

Related Stem Cells Articles:

Computer simulations visualize how DNA is recognized to convert cells into stem cells
Researchers of the Hubrecht Institute (KNAW - The Netherlands) and the Max Planck Institute in Münster (Germany) have revealed how an essential protein helps to activate genomic DNA during the conversion of regular adult human cells into stem cells.
First events in stem cells becoming specialized cells needed for organ development
Cell biologists at the University of Toronto shed light on the very first step stem cells go through to turn into the specialized cells that make up organs.
Surprising research result: All immature cells can develop into stem cells
New sensational study conducted at the University of Copenhagen disproves traditional knowledge of stem cell development.
The development of brain stem cells into new nerve cells and why this can lead to cancer
Stem cells are true Jacks-of-all-trades of our bodies, as they can turn into the many different cell types of all organs.
Healthy blood stem cells have as many DNA mutations as leukemic cells
Researchers from the Princess Máxima Center for Pediatric Oncology have shown that the number of mutations in healthy and leukemic blood stem cells does not differ.
New method grows brain cells from stem cells quickly and efficiently
Researchers at Lund University in Sweden have developed a faster method to generate functional brain cells, called astrocytes, from embryonic stem cells.
NUS researchers confine mature cells to turn them into stem cells
Recent research led by Professor G.V. Shivashankar of the Mechanobiology Institute at the National University of Singapore and the FIRC Institute of Molecular Oncology in Italy, has revealed that mature cells can be reprogrammed into re-deployable stem cells without direct genetic modification -- by confining them to a defined geometric space for an extended period of time.
Researchers develop a new method for turning skin cells into pluripotent stem cells
Researchers at the University of Helsinki, Finland, and Karolinska Institutet, Sweden, have for the first time succeeded in converting human skin cells into pluripotent stem cells by activating the cell's own genes.
In mice, stem cells seem to work in fighting obesity! What about stem cells in humans?
This release aims to summarize the available literature in regard to the effect of Mesenchymal Stem Cells transplantation on obesity and related comorbidities from the animal model.
TSRI researchers identify gene responsible for mesenchymal stem cells' stem-ness'
Researchers at The Scripps Research Institute recently published a study in the journal Cell Death and Differentiation identifying factors crucial to mesenchymal stem cell differentiation, providing insight into how these cells should be studied for clinical purposes.
More Stem Cells News and Stem Cells Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Teaching For Better Humans 2.0
More than test scores or good grades–what do kids need for the future? This hour, TED speakers explore how to help children grow into better humans, both during and after this time of crisis. Guests include educators Richard Culatta and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#556 The Power of Friendship
It's 2020 and times are tough. Maybe some of us are learning about social distancing the hard way. Maybe we just are all a little anxious. No matter what, we could probably use a friend. But what is a friend, exactly? And why do we need them so much? This week host Bethany Brookshire speaks with Lydia Denworth, author of the new book "Friendship: The Evolution, Biology, and Extraordinary Power of Life's Fundamental Bond". This episode is hosted by Bethany Brookshire, science writer from Science News.
Now Playing: Radiolab

Space
One of the most consistent questions we get at the show is from parents who want to know which episodes are kid-friendly and which aren't. So today, we're releasing a separate feed, Radiolab for Kids. To kick it off, we're rerunning an all-time favorite episode: Space. In the 60's, space exploration was an American obsession. This hour, we chart the path from romance to increasing cynicism. We begin with Ann Druyan, widow of Carl Sagan, with a story about the Voyager expedition, true love, and a golden record that travels through space. And astrophysicist Neil de Grasse Tyson explains the Coepernican Principle, and just how insignificant we are. Support Radiolab today at Radiolab.org/donate.