Posts Tagged‘mice’

Cleaning Out Old Cells Prevents Aging in Mice.

Aging, as a process, still remains a mystery to modern science. We know that it’s not just one thing that causes the symptoms of aging which is what makes it so hard to find a miracle compound that erases everything. Still we’ve made some pretty good progress in combating some parts of the aging process, many of which can be used to make our lives not only longer but also far more healthier throughout. The latest research from scientists at the Mayo clinic shows yet another potential pathway for delaying the onset of age related diseases and conditions, giving mice up to 35% longer lives.

Lab_mouse_mg_3263

The mechanism that the researchers focused on is called cellular senescence. Our cells constantly reproduce themselves through division, a process which repeats for each cell approximately 40 to 60 times before it enters a stage called cellular senescence. In this stage the cell’s telomeres, a kind of nucleotide that protects a cell’s DNA from damage, is shortened to the point where it can no longer provide the protection the cell needs. In this stage the cell will no longer divide but still remains active. Eventually these senescent cells are cleaned out by the body’s immune system but as we age this process starts to slow down and become less efficient.

The Mayo researchers used an existing transgene line, called INK-ATTAC, to induce cell death in these senescent cells. This was triggered by twice weekly injections into two different lines of lab mice who were then compared to a control. The results were incredibly impressive, showing an improvement in overall lifespan of the mice from 17% to 35%. The mice also showed no side effects from the treatment with healthy major organ function retained throughout their extended life. Suffice to say a treatment of this nature would appear to be of incredible benefit to many, especially those who are seeking more healthy years than just an extended lifespan.

Such a treatment is probably many years away from reaching humans however, mostly due to the fact that the use of transgenes in humans is still an open area of bioethical debate. Indeed whilst the consensus for using such treatments for curative purposes appears to be largely agreed upon therapeutic uses such as these are still something of a grey area. Transgenes like this one are still very much an area of active research however and there are likely to be many more such treatments like these developed in the coming years. Hopefully the regulatory and ethical frameworks will be able to keep up with the rapid pace of innovation as treatments like these are invaluable in treating the one condition that affects all humans universally.

First Whole Organ Grown Inside Mice.

The need for organs for transplants has always outstripped demand and this has pushed the science in some pretty amazing directions. Indeed one of the most incredible advances is the ability to strip away host tissue from organs, leaving behind an organ scaffold, that we can then regrow with the recipient’s own cells. This drastically reduces the chance of rejection and hopefully avoids the patient having to take the harsh anti-rejection drugs. However such a process still relies on a donor organ which still leaves us with the supply problem to deal with. Whilst we’ve made some advances in creating parts of organs (some even done with biomedical 3D printers) growing a full organ has still proven elusive.

That is until recently.

SCIENCE MOUSEResearchers at the University of Edinburgh have, for the first time, managed to grow a full functioning organ within a mouse using only a single injection. The organ that they created was the thymus, an organ that plays a critical role in the production of T-cells. These cells are the ones that are responsible for hunting down cells in your body that are either showing abnormalities or signs of infection and then eradicating them. What’s so incredible about this recent achievement is that the functional thymus developed after the injection of modified cells, requiring none of the additional work that’s previously been associated with creating functional organs.

The process starts off with cells from a mouse embryo, which from what I can gather were likely to be embryonic stem cells, which were then genetically programmed to form into a type of cell that’s found in the thymus. These, along with supporting cells, were then injected into the mice and the resultant cells developed into a fully functioning thymus. Interestingly though this didn’t seem to be the outright goal of the program as the researchers themselves stated that the result was surprising. Indeed whilst it’s been theorized that stem cells could be used in this manner it was never thought to be as straight forward as this and with these results further research is definitely on the table.

Whilst this research is still many years away from being useful in human models it does pave the way for research into how far this typical method can be applied. The thymus is a relatively simple organ when compared to others in the body so the next steps will be to see if this same process can be used to replicate them. If say a liver or heart can be reproduced in this manner then this has the potential to completely solve the transplant organ supply issue, allowing patients (or a surrogate) to grow their own organs for transplants. There’s a lot of research to be done before that happens however but this latest advance is incredibly promising.

 

The Fountain of Youth Might Just be The Blood of the Young.

Aging is one of the most complex and nuanced processes that our body goes through, radically transforming us over the course of several decades. Whilst some of the basic mechanisms are well understood, like accumulated damage to DNA during its reproduction, the rest remains something of a mystery. Indeed once we get into the extreme end of the spectrum the factors that seem to influence longevity become a lot more muddled, with many octogenarians engaging in behaviours that would appear to be the antithesis to living longer. Still our quest for the proverbial fountain of youth has had us searching through the many different mechanisms at play in the aging process and it seems that the blood of our young might hold the clues to a longer life.

Lab Mouse

Two pieces of recent research point towards some interesting evidence that shows the radical differences between the blood of the young and the elderly. Hendrikje van Andel-Schipper was once the oldest woman in the world, reaching the ripe old age of 115 in the year 2005. She was in remarkable condition for her age, remaining mentally aware and alert right up until her death. In a great boon to the greater scientific community she donated her body for study giving us unprecedented insight into what happens to us as we age. That, combined with some recent research data coming at this from a different perspective, shows that the contents of our blood changes dramatically as we age and, possibly, that we could reinvigorate ourselves with transfusions from our younger selves.

At the end of her life all of Hendrikje’s white blood cells, the ones responsible for fighting off infections, came from a mere 2 stem cells. It is estimated that we begin our lives with around 20,000 such cells with around 5% of them working at any one time to replenish our white cell supply. The fact that Hendrikje had only two function stem cells remaining points to an upper limit on the natural human age as once you stop producing white blood cells it wouldn’t take long for your body to succumb to any number of diseases. Curiously though this also hints a potential pathway to reinvigorate individuals whose white cell count has deteriorated, by injecting them with their own blood (or potentially someone else’s) taken from many years previous.

That part was mostly conjecture on the part of the researchers but recent results from a study  at Stanford University have shown that old mice injected with the blood of younger mice show significant improvement in cognitive function. Whilst this isn’t likely to be the same mechanism that the previous research may have indicated (blood plasma with the proteins denatured in it didn’t achieve the same result) it does point towards a potential therapeutic pathway for combating some age related maladies. Of course whether this translates into a human model remains to be seen and who knows if this kind of thing would get passed an ethics tribunal.

Indeed research of this nature opens up all sorts of ethical questions as if it’s shown that blood transfusions can improve the quality of life of patients then it becomes imperative for doctors to use it. With blood supplies always being in high demand the question of where they can do the most good comes to the forefront, a troubled area that really has no good answers. Still if you could better the life of another, most likely a relative, by simply giving blood I’m sure many of us would do it, but the larger question of voluntary donations still remains.

There’s also some potentially dark sci-fi film in here about people being bled dry in order to feed an underground transfusion market but I’ll leave that one up to your imagination.

Australian, US Researchers Dramatically Reverse Aging in Mice.

I’m something of a quiet transhumanist, reveling in the ideas of elevating the human existence through the use of technology but staving off from raving about it whenever I get the chance. Whilst the idea of living longer appeals to many the idea of removing that inevitable end date, the one thing that has proved to be unavoidable for the vast majority of humanity to date, feels abhorrent to many and thus I leave the subject to one side. Still every so often a piece of science will make it into the mainstream media that brings with it some of the implications of transhumanist thinking and I feel compelled to comment on it.

TranshumanMichelangeloA collaborative research effort between scientists in Australia and the USA has discovered a compound which, when administered to 2 year old mice, makes them appear to be as youthful as their 6 month old counterparts. The time line for the dramatic effects was also impressive with the reversal taking just under a week to occur. The compound acts on mitochondria, the energy generators of our cells, and appears to act directly on the muscle tissue of the mice. Whether that extends to other aspects of aging isn’t made clear (at least not that I can see, the article is behind a paywall) but the results have been impressive enough to warrant approval for human trials next year. Of course that means that a proper human model is some years off (with commercial production further still) but we should have some preliminary results in the not too distant future.

If this compound does pretty much exactly as advertised then it could mean a lot for our aging populace. Restoring muscle function is a key aspect in leading a healthier life as we age (which is why regular exercise is so important) and this could go a long way to making our golden years that much more enjoyable. At the same time it could also potentially help keep us in physical peak condition much longer, enabling us to be more active for an extended period of time. Whether this will translate to a bump in life expectancy and, more importantly, total longevity though will be something we won’t know for decades but it does sound promising.

Of course such life extension technologies always beg the question of how we’d deal with a larger population that’s living longer. Currently the world’s population is expected to peak around 2050 at roughly 8.3 billion, about 1.3 billion above what it is today. Technology like this wouldn’t immediately mean everyone suddenly starts living an additional 20~30 years, due to cost and adoption rates, so it’s far more likely that you’d see a gradual increase in average lifespan over the course of a couple decades. Indeed I believe this is true for all life extending technologies and thus their effects would be far more subtle and would be highly unlikely to lead to an unsustainable population of people who live forever.

It’s my hope that this line of research paves the way for more studies into what causes aging and what we can do to treat it. Whilst I will always support people’s decisions to live their lives the way they choose I believe that medical science can do a lot to help improve it and, one day, make death a choice rather than an inevitability.