Thomson, Nobel Prize winning physicist, discoverer of the electron.
Now, scientists at the Salk Institute have found that intermittent expression of genes normally associated with an embryonic state can reverse the hallmarks of old age. The early-stage work provides insight both into the cellular drivers of aging and possible therapeutic approaches for improving human health and longevity.
In fact, data shows that the biggest risk factor for heart disease, cancer and neurodegenerative disorders is simply age.
One clue to halting or reversing aging lies in the study of cellular reprogramming, a process in which the expression of four genes known as the Yamanaka factors allows scientists to convert any cell into induced pluripotent stem cells iPSCs.
Like embryonic stem calls, iPSCs are capable of dividing indefinitely and becoming any cell type present in our body. Salk Institute researchers discover that partial cellular reprogramming reversed cellular signs of aging such as accumulation of DNA damage.
Left Progeria mouse fibroblast cells; right progeria mouse fibroblast cells rejuvenated by partial reprogramming. Click here for a high-resolution image Credit: For one thing, although rapid cell division is critical in growing embryos, in adults such growth is one of the hallmarks of cancer. For another, having large numbers of cells revert back to embryonic status in an adult could result in organ failure, ultimately leading to death.
For these reasons, the Salk team wondered whether they could avoid cancer and improve aging characteristics by inducing the Yamanaka factors for a short period of time. To find out, the team turned to a rare genetic disease called progeria.
Both mice and humans with progeria show many signs of aging including DNA damage, organ dysfunction and dramatically shortened lifespan. Moreover, the chemical marks on DNA responsible for the regulation of genes and protection of our genome, known as epigenetic marks, are prematurely dysregulated in progeria mice and humans.
Importantly, epigenetic marks are modified during cellular reprogramming. Induction of reprogramming improved muscle regeneration in aged mice. Left impaired muscle repair in aged mice; right improved muscle regeneration in aged mice subjected to reprogramming.
Click here for a high-resolution image. Salk Institute Using skin cells from mice with progeria, the team induced the Yamanaka factors for a short duration.
When they examined the cells using standard laboratory methods, the cells showed reversal of multiple aging hallmarks without losing their skin-cell identity. The results were striking: Compared to untreated mice, the reprogrammed mice looked younger; their cardiovascular and other organ function improved and—most surprising of all—they lived 30 percent longer, yet did not develop cancer.
On a cellular level, the animals showed the recovery of molecular aging hallmarks that are affected not only in progeria, but also in normal aging.
Salk Institute Lastly, the Salk scientists turned their efforts to normal, aged mice. In these animals, the cyclic induction of the Yamanaka factors led to improvement in the regeneration capacity of pancreas and muscle.
In this case, injured pancreas and muscle healed faster in aged mice that were reprogrammed, indicating a clear improvement in the quality of life by cellular reprogramming. However, they caution that, due to the complexity of aging, these therapies may take up to 10 years to reach clinical trials.Feb 02, · There’s always a cost to progress, but there are times when scientists take it a step too far.
Ignoring basic human rights in order to perform valuable research is still ignoring basic human rights, and the cost of lives can be staggering.
The Truth about Genetically Modified Food. Proponents of genetically modified crops say the technology is the only way to feed a warming, increasingly populous world. Multiple studies published in peer-reviewed scientific journals 1 show that 97 percent or more of actively publishing climate scientists agree*: Climate-warming trends over the past century are extremely likely due to human grupobittia.com addition, most of the leading scientific organizations worldwide have issued public statements endorsing this position.
Many scientists refute AGW (manmade global warming) with solid facts, data and research. Some even show evidence of global cooling. Surveys of scientists' views on climate change – with a focus on human-caused or anthropogenic global warming (AGW) – have been undertaken since the s.
A paper (which was co-authored by Naomi Oreskes, Peter Doran, William Anderegg, Bart Verheggen, Ed Maibach, J. Stuart Carlton and John Cook, and which was based on a half a dozen independent studies by the authors) concluded .
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