Interesting analogy between the aging process and the meltdown of the global economy – the common denominator being loss of regulation.
The Aging Process and the Current Financial Mess
Courtesy of Stormy, at Angry Bear.
I just could not resist posting this latest tidbit about the aging process:
Like our current financial crisis, the aging process might also be a product excessive deregulation.
Nearly a decade ago, Sinclair and colleagues in the Massachusetts Institute of Technology lab of Leonard Guarente found that a particular sirtuin in yeast affected the aging process in two specific ways—it helped regulate gene activity in cells and repair breaks in DNA. As DNA damage accumulated over time, however, the sirtuin became too distracted to properly regulate gene activity, and as a result, characteristics of aging set in.
"Too distracted" is clearly too anthropomorphic a phrase, but in a curious way, it fits the present crisis. But wait.
The researchers have added an "enlightening" twist to the idea of "distraction":
The problem for the cell, however, is that the sirtuin has another important job. When DNA is damaged by UV light or free radicals, sirtuins act as volunteer emergency responders. They leave their genomic guardian posts and aid the DNA repair mechanism at the site of damage.
"Distraction" is now operationally defined.
The marvelous genetic aging metaphor is ready for completion. All we have to do is to define what is presently keeping the overseers of our economic system from paying attention to the real problem.
Once we thought of the world in mechanical terms; now the world of genetics is opening a new way of looking at the world.
ScienceDaily — Researchers have uncovered what may be a universal cause of aging, one that applies to both single cell organisms such as yeast and multicellular organisms, including mammals. This is the first time that such an evolutionarily conserved aging mechanism has been identified between such diverse organisms.
The mechanism probably dates back more than one billion years. The study shows how DNA damage eventually leads to a breakdown in the cell’s ability to properly regulate which genes are switched on and off in particular settings.
Like our current financial crisis, the aging process might also be a product excessive deregulation.
Researchers have discovered that DNA damage decreases a cell’s ability to regulate which genes are turned on and off in particular settings. This mechanism, which applies both to fungus and to us, might represent a universal culprit for aging.
"This is the first potentially fundamental, root cause of aging that we’ve found," says Harvard Medical School professor of pathology David Sinclair. "There may very well be others, but our finding that aging in a simple yeast cell is directly relevant to aging in mammals comes as a surprise."
These findings appear in the November 28 issue of the journal Cell.
For some time, scientists have know that a group of genes called sirtuins [the genes are blueprints to make the sirtuins, which are proteins] are involved in the aging process. These genes, when stimulated by either the red-wine chemical resveratrol or caloric restriction, appear to have a positive effect on both aging and health.
Nearly a decade ago, Sinclair and colleagues in the Massachusetts Institute of Technology lab of Leonard Guarente found that a particular sirtuin in yeast affected the aging process in two specific ways—it helped regulate gene activity in cells and repair breaks in DNA. As DNA damage accumulated over time, however, the sirtuin became too distracted to properly regulate gene activity, and as a result, characteristics of aging set in.
Oberdoerffer found that a primary function of sirtuin in the mammalian system was to oversee patterns of gene expression (which genes are switch on and which are switch off). While all genes are present in all cells, only a select few need to be active at any given time. If the wrong genes are switched on, this can harm the cell…
The problem for the cell, however, is that the sirtuin has another important job. When DNA is damaged by UV light or free radicals, sirtuins act as volunteer emergency responders. They leave their genomic guardian posts and aid the DNA repair mechanism at the site of damage.
During this unguarded interval, the chromatin wrapping may start to unravel, and the genes that are meant to stay silent may in fact come to life.
For the most part, sirtuins are able to return to their post and wrap the genes back in their packaging, before they cause permanent damage. As mice age, however, rates of DNA damage (typically caused by degrading mitochondria) increase. The authors found that this damage pulls sirtuins away from their posts more frequently. As a result, deregulation of gene expression becomes chronic. Chromatin unwraps in places where it shouldn’t, as sirtuin guardians work overtime putting out fires around the genome, and the unwrapped genes never return to their silent state.
In fact, many of these haplessly activated genes are directly linked with aging phenotypes. The researchers found that a number of such unregulated mouse genes were persistently active in older mice.
"We then began wondering what would happen if we put more of the sirtuin back into the mice," says Oberdoerffer. "Our hypothesis was that with more sirtuins, DNA repair would be more efficient, and the mouse would maintain a youthful pattern gene expression into old age."
That’s precisely what happened…
"According to this specific mechanism, while DNA damage exacerbates aging, the actual cause is not the DNA damage itself but the lack of gene regulation that results," says Oberdoerffer. "Lots of research has shown that this particular process of regulating gene activity, otherwise known as epigenetics, can be reversed—unlike actual mutations in DNA. We see here, through a proof-of-principal demonstration, that elements of aging can be reversed."…