Stem cells in the brain could be the key to extending life and slowing ageing. These cells which are located in the hypothalamus, a region that produces hormones and other signalling molecules can reinvigorate declining brain function and muscle strength in middle-aged mice, according to a study published on July 26in Nature1.

Previous studies have suggested that the hypothalamus is involved in ageing, but the latest research shows that stem cells in this region can slow the process. That makes sense, because the hypothalamus is involved in many bodily functions, including inflammation and appetite, says Dongsheng Cai, a neuroendocrinologist at Albert Einstein College of Medicine in New York City.

In their study, Cai and his colleagues found that stem cells in the hypothalamus disappear as mice grow older. When the researchers injected their mice with viruses that destroy these cells, the animals seemed to grow older faster, experiencing declines in memory, muscle strength, endurance and coordination. They also died sooner than untreated mice of the same age.

Next, the team injected stem cells taken from the hypothalami of newborn mice into the brains of middle-aged mice. After four months, these animals had better cognitive and muscular function than untreated mice of the same age. They also lived about 10% longer, on average.

The researchers found that these stem cells release molecules called microRNAs, which help to regulate gene expression, into the cerebrospinal fluid. When the team injected these microRNAs into the brains of middle-aged mice, they found that the molecules slowed cognitive decline and muscle degeneration.

It's an interesting paper, says Leonard Guarente, a molecular biologist at the Massachusetts Institute of Technology in Cambridge, who studies ageing. He adds that it could lead to various ways of developing anti-ageing therapies in people.

Stem-cell therapies might enhance the ability of the hypothalamus to act as a master regulator, given that the latest results suggest it controls ageing through signalling peptides such as hormones and microRNAs, Cai says. He says that his team is trying to identify which of the thousands of types of microRNA produced are involved in ageing, and hopes to investigate whether similar mechanisms exist in non-human primates.

The findings represent a breakthrough in ageing research, says Shin-ichiro Imai, who studies ageing at Washington University in St Louis, Missouri. The next steps would be to link these stem cells with other physiological mechanisms of ageing, he says. For instance, these cells may have a role in regulating the neurons that release a hormone called GnRH, which is secreted by the hypothalamus and is associated with ageing. Imai would also like to know whether the microRNAs from the cells can pass into the bloodstream, which would carry them throughout the body.

Cai suspects that anti-ageing therapies targeting the hypothalamus would need to be administered in middle age, before a persons muscles and metabolism have degenerated beyond a point that could be reversed.

It is unclear by how much such a therapy could extend a human lifespan, but Guarente says that slowing the effects of ageing is the more important goal. Living longer isnt important if youre not healthy, he says.

This article is reproduced with permission and wasfirst publishedon July 26, 2017.

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Brain's Stem Cells Slow Aging in Mice - Scientific American

Patrick Landmann/SPL

Mice aged more slowly when injected with stem cells from the brains of newborns.

Stem cells in the brain could be the key to extending life and slowing ageing. These cells which are located in the hypothalamus, a region that produces hormones and other signalling molecules can reinvigorate declining brain function and muscle strength in middle-aged mice, according to a study published on 26 July in Nature1.

Shamini Bundell discovers more about the brains role in ageing

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Previous studies have suggested that the hypothalamus is involved in ageing, but the latest research shows that stem cells in this region can slow the process. That makes sense, because the hypothalamus is involved in many bodily functions, including inflammation and appetite, says Dongsheng Cai, a neuroendocrinologist at Albert Einstein College of Medicine in New York City.

In their study, Cai and his colleagues found that stem cells in the hypothalamus disappear as mice grow older. When the researchers injected their mice with viruses that destroy these cells, the animals seemed to grow older faster, experiencing declines in memory, muscle strength, endurance and coordination. They also died sooner than untreated mice of the same age.

Next, the team injected stem cells taken from the hypothalami of newborn mice into the brains of middle-aged mice. After four months, these animals had better cognitive and muscular function than untreated mice of the same age. They also lived about 10% longer, on average.

The researchers found that these stem cells release molecules called microRNAs, which help to regulate gene expression, into the cerebrospinal fluid. When the team injected these microRNAs into the brains of middle-aged mice, they found that the molecules slowed cognitive decline and muscle degeneration.

It's an interesting paper, says Leonard Guarente, a molecular biologist at the Massachusetts Institute of Technology in Cambridge, who studies ageing. He adds that it could lead to various ways of developing anti-ageing therapies in people.

Stem-cell therapies might enhance the ability of the hypothalamus to act as a master regulator, given that the latest results suggest it controls ageing through signalling peptides such as hormones and microRNAs, Cai says. He says that his team is trying to identify which of the thousands of types of microRNA produced are involved in ageing, and hopes to investigate whether similar mechanisms exist in non-human primates.

The findings represent a breakthrough in ageing research, says Shin-ichiro Imai, who studies ageing at Washington University in St Louis, Missouri. The next steps would be to link these stem cells with other physiological mechanisms of ageing, he says. For instance, these cells may have a role in regulating the neurons that release a hormone called GnRH, which is secreted by the hypothalamus and is associated with ageing. Imai would also like to know whether the microRNAs from the cells can pass into the bloodstream, which would carry them throughout the body.

Cai suspects that anti-ageing therapies targeting the hypothalamus would need to be administered in middle age, before a persons muscles and metabolism have degenerated beyond a point that could be reversed.

It is unclear by how much such a therapy could extend a human lifespan, but Guarente says that slowing the effects of ageing is the more important goal. Living longer isnt important if youre not healthy, he says.

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Brain's stem cells slow ageing in mice - Nature.com

When it comes to nematodes, unraveling the root of the issue is complicated. These tiny parasites siphon off the nutrients from the roots of important crops like soybeans, and scientists keep uncovering more about how they accomplish this task. Research from the University of Missouri lab of Dr. Melissa Mitchum recently pinpointed a new way nematodes take over root cells.

In a normal plant, the plant sends different chemical signals to form different types of structures for a plant. One of those structures is the xylem for nutrient flow, Plant researchers discovered a peptide signal for vascular stem cells several years ago, but this is the first time anyone has proven that a nematode is also secreting chemical mimics to keep these stem cells from changing into the plant structures they normally would.

Stem cells? Xylem? Chemical mimics? Lets unpack whats going on.

First, all plants contain stem cells. These are cells with unbridled potential and are at the growth centers in a plant. Think the tips of shoots and roots. With the right urging, plant stem cells can turn into many different types of cells.

That influence often comes in the form of chemicals. These chemicals are typically made inside the plant and when stem cells are exposed to them at the right time, they turn certain genes either on or off that in turn start a transformation of these cells into more specialized organs.

Want a leaf? Expose a stem cell to a particular combination of chemicals. Need a root? Flood it with a different concoction of peptides. The xylem the dead cells that pipe water and nutrients up and down the plant requires a particular type of peptide that connects with just the right receptor to start the process.

But for a nematode, the plan is to hijack the plants plan and make plant cells feed it. This microscopic worm attaches itself to a root and uses a needle-like mouthpiece to inject spit into a single root cell. That spit contains chemical signals of its own engineered to look like plant signals. In this case, these chemicals B-type CLE peptides and their purpose are just being discovered by Mitchums lab.

Now a nematode doesnt want to turn its feeding site into xylem because these are dead cells it cant use, so they may be tapping into part of the pathway required to maintain the stems cells while suppressing xylem differentiation to form a structure that serves as a nutrient sink, Mitchum said. To me thats really cool.

This means these cells are free to serve the nematode. Many of their cell walls dissolve to create a large nutrient storage container for the nematode and some create finger-like cell wall ingrowths that increase the take up of food being piped through the roots. For a nematode, thats a lifetime of meals for it while it sits immobile, just eating.

But how did scientists figure out and test that this nematodes chemical was the cause?

Using next generation sequencing technologies that were previously unavailable, Michael Gardner, a graduate research assistant, and Jianying Wang, a senior research associate in Mitchums lab, compared the pieces of the plant and nematode genome and found nearly identical peptides in both B-type CLE peptides.

Everything is faster, more sensitive and we can detect things that had gone undetected through these technological advances that didnt exist 10 years ago, Mitchum said.

To test their theory, Xiaoli Guo, postdoctoral researcher and first author of the study in Mitchums lab synthesized the B-type CLE nematode peptide and applied it to vascular stem cells of the model plant Arabidopsis. They found that the nematode peptides triggered a growth response in much the same way as the plants own peptides affected development. They used mutant Arabidopsis plants engineered to not be affected as much by this peptide to confirm their findings. We knocked out genes in the plant to turn off this pathway, and that caused the nematodes feeding cell to be compromised. Thats why you see reduced development of the nematode on the plants.

This all matters because these tiny nematodes cost U.S. farmers billions every year in lost yields from soybeans, and similar nematodes affect sugar beets, potatoes, corn and other crops. While this discovery is just a piece of a puzzle, these pieces hopefully will come together to build better crops. You have to know what is happening before you can intervene, Mitchum said. Now our biggest hurdle is to figure out how to not compromise plant growth while blocking only the nematodes version of this peptide.

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Chemical persuasion by David Sparks Ph.d, click here for bio - AgInfo.net (press release) (registration) (blog)

Researchers at the University of Missouri have made a discovery that could decrease the costs associated with IVF in humans and it all started with piglets.

The laboratories of Dr. Michael Roberts and Dr. Randall Prather, both University of Missouri Curators' Professors, work with pigs to research stem cells. During an attempt to improve how they grew these cells, researchers stumbled across a method to improve the success of IVF in pigs.

Their discovery doubles the number of piglets born and speeds up the entire IVF process by 400%, which significantly increases both the efficiency of experiments and their potential application to other species. The journal Proceedings of the National Academy of Sciences published their work July 3 in itsonline early edition.

"It was a serendipitous discovery, really," Roberts says. "Generally, there are multiple steps to producing viable embryos that we can then implant in pigs and cows involved in our research; however, it's costly and sometimes yields very little return. We were seeking a way to do that more efficiently and stumbled upon a method that may have implications in human fertility clinics as well."

Increasing eggsIn IVF involving pigs, scientists first extract oocytes (eggs) from female pigs, as well as the "nurse" cells that surround them, and place them in a chemical environment designed to mature the eggs. The eggs are then fertilized to create zygotes, or single-celled embryos that are allowed to develop for six days. These embryos are then transferred back into a female pig with the hope of achieving a successful pregnancy and healthy piglets.

The chance of generating a successful piglet after all those steps is very low; generally, less than 2% of the original oocytes make it that far, Roberts says. "Normally, researchers overcome this low success rate by implanting large numbers of embryos, but that takes a lot of time and money."

Ye Yuan, a former research assistant professor in Roberts' lab, and Lee Spate, a senior research specialist in animal sciences, were tasked with increasing the efficiency and quality of piglet embryos before they are implanted.

It took 3In one study, the team analyzed various special growth factors used when culturing pig stem cells and added two factors fibroblast growth factor 2 (FGF2) and leukemia inhibitory factor (LIF). They found that this combination, when added with a third factor insulin-like growth factor created the special fluid environment the oocytes needed to become competent for fertilization, and further development to embryos, that could provide a successful pregnancy.

Together, the three compounds create the chemical medium called "FLI," which could revolutionize both piglet and human IVF treatments; a patent application has been filed through the MU Office of Technology Management and Industry Relations to encourage commercialization of the new method.

"It improved every aspect of the whole process and almost doubled the efficiency of oocyte maturation," Roberts says. "Whenever you're doing science, you'd like to think you're doing something that could be useful. When we started it wasn't to improve fertility IVF in women, it was to just get better oocytes in pigs. Now it's possible that FLI medium could become important in bovine embryo work, and possibly even help with human IVF."

Source: University of Missouri, Columbia

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Pig research could improve IVF in humans - Wallace's Farmer