At a promising step towards eternal youth, scientists have used cellular “rejuvenation” techniques to reverse the aging process in middle-aged and aged mice.
California-based experts have shown that four molecules known as the Yamanaka transcription factor can be used to partially reset mouse cells to a “younger state.”
After injecting these molecules into mice of various ages, the animal’s kidneys and skin showed promising signs of rejuvenation, but skin cells were more capable of proliferating and could form permanent scars. It became low.
Researchers say their “safe” treatments can one day help humans rewind their biological clocks and reduce their risk of cardiovascular disease and cancer.
Studies show that a treatment period of 7 to 10 months may be required to stop the unwanted side effects of aging.
As an organism ages, every cell in the body has a molecular clock that keeps track of the passage of time.Cell rejuvenation therapy can safely reverse the signs of aging in mice
Epigenetics and Yamanaka Factor
As an organism ages, every cell in the body has a molecular clock that keeps track of the passage of time.
Cells isolated from the elderly and animals have different patterns of chemicals, called epigenetic markers, along the DNA than younger people.
Scientists know that adding a mixture of four reprogramming molecules (Yamanaka transcription factor; Oct4, Sox2, Klf4, cMyc) to cells can reset these epigenetic marks to their original pattern.
“This technology is safe and effective in mice,” said Juan Carlos Izpisua Belmonte, co-author and professor at the Salk Institute for Biological Studies in San Diego, California.
“We are pleased to be able to use this approach for life to delay the aging of normal animals.
“In addition to tackling age-related diseases, this approach provides new tools for restoring tissue and biological health by improving cell function and resilience in a variety of disease situations, including neurodegenerative diseases. May provide to the biomedical community. ”
The Yamanaka transcription factors (Oct4, Sox2, Klf4, cMyc) were first pioneered over 15 years ago by Dr. Shinya Yamanaka, a Nobel Prize-winning Japanese scientist.
Dr. Yamanaka discovered that by adding four gene regulatory proteins to cells, they can be “reprogrammed” back into a younger, much more adaptive form, the so-called “embryonic stem cells.” did.
Embryonic stem cells are pluripotent and therefore capable of becoming all cell types of the body. That is, it can produce many different cell types.
2016, Izpisua Belmonte’s laboratory at the Salk Institute Reported for the first time Yamanaka factor can be used to combat signs of aging and extend the lifespan of mice with premature aging disease.
“But the effect of long-term partial reprogramming on physiologically aged wild-type mice is unclear,” the authors point out in their new study.
Long-term reprogramming reduced the formation of fibrous tissue during skin wound healing
Stem cells: embryonic and adult
Stem cells are special human cells that have the ability to develop into many different cell types, from muscle cells to brain cells.
In some cases, it also has the ability to repair damaged tissue.
Stem cells are divided into two main forms: embryonic stem cells and adult stem cells.
Embryonic stem cells are pluripotent and can be of any cell type in the body. They can produce many different cell types.
Adult stem cells are found in most adult tissues such as bone marrow and fat, but their ability to produce various cells in the body is limited.
Induced pluripotent stem cells (iPSCs), on the other hand, are genetically reprogrammed adult cells, such as embryonic stem cells.
To investigate this, the team tested variations in cell rejuvenation approaches as healthy animals age over time.
One group of mice was regularly treated with Yamanaka factor from 15 to 22 months of age. This is roughly equivalent to the age of 50-70 in humans.
Another group was treated at 12-22 months (about 35-70 years in humans) and the third group was treated at 25 months (similar to 80 years in humans) for only 1 month.
“What we really wanted to establish was that it was safe to use this approach for a longer period of time,” said Pradeep Lady, also a research author at the Salk Institute.
“Sure, there was no negative impact on the health, behavior or weight of these animals.”
Compared to control animals, mice treated with Yamanaka factor had no blood cell or neurological changes. Also, none of the groups had cancer.
Researchers examined the signs of normal aging in treated animals and found that mice resemble young animals.
The epigenetics of the treated animals, both in the kidney and in the skin, were more similar to the epigenetic patterns found in young animals.
To determine if reprogramming can reduce tissue fibrosis (tissue overgrowth, hardening, or scarring), the team analyzed tissue accumulation in post-healing skin wounds.
“We observed an increase in collagen deposition in the wound area of old untreated mice, but long-term partially reprogrammed mice had lower wound area fibrosis, similar to young mice.” The team said in their paper.
In this study, the team tested variations in cell rejuvenation approaches as mice age. One group of mice was regularly treated with Yamanaka factor from 15 to 22 months of age. This is roughly equivalent to the age of 50-70 in humans. Another group was treated at 12-22 months (35-70 years in humans) and the third group was treated at 25 months (80 years in humans) for only one month.
In addition, the metabolic molecules in the blood of the treated animals showed no normal age-related changes.
This youth was observed in animals treated with Yamanaka factor for 7-10 months, but not in animals treated for only 1 month.
In addition, analysis of treated animals during treatment did not reveal their effects.
This suggests that treatment does not simply pause aging, but actively retreats it – more research is needed to distinguish between the two.
This study includes what is known as the Yamanaka transcription factor, named after Dr. Shinya Yamanaka, a Japanese scientist who won the Nobel Prize (photo).
The team is now working on how long-term treatment with Yamanaka factor changes certain molecules and genes, and Develop new ways to provide factors.
“At the end of the day, we want to restore resilience and function to old cells, making them more resistant to stress, injury and illness,” says Reddy.
“This study shows that there is a way to achieve that, at least in mice.”
The study is published at Nature aging..
The exercise “Sweet Spot” discovered to reverse cognitive decline in aged mice may help pave the way for human dementia treatment, research suggestions
A new study suggests that an exercise “sweet spot” that has been found to reverse cognitive decline in mice could one day be used to help people with dementia.
In an experiment with aged mice, Australian researchers found that exercising for 35 consecutive days was a “sweet spot” for reversing learning disabilities in 24-month-old mice.
Curiously, the researchers found that longer or shorter periods of exercise proved ineffective in reversing this decline in cognitive function.
This result paves the way for human research to investigate the effects of specific exercise times that reverse the effects of dementia.
The new study was led by researchers at the Queensland Brain Institute (QBI) at the University of Queensland, Australia.
“We tested the cognitive abilities of aged mice after a defined exercise period and found an optimal period or” sweet spot “that significantly improved spatial learning,” said research author Dr. Dan Blackmore.