It's Not Often I Go "Er ... wow!"

[Sukerkin]

I have just watched a lecture given by Professor Kaku on the 'near future' of technology.

Amidst all the physics talk that was sort of familiar because, oddly enough, of my taste for science fiction, something came out whilst he was speaking on the science of aging that quite set me back on my heels.

Apparently, there are some species of creature on Earth that do not die of old age! Crocodiles are one of them. They simply keep on getting bigger and bigger, not aging in a detrimental sense at all, until their environment can no longer sustain them.

Now starving to death is hardly a glamarous end for what seems to be an immortal organism but the very concept took my breath away.

 

[Ken Morgan]

Cool, I didn’t know that about crocodiles.

Now if only those damn crocs would die out, I’d be happy!! I popped over to the mall today to pick some stuff up for a lesson tomorrow, the elderly lady in front of me in line was wearing crocs….its -3 C outside with snow on the ground!!…. WTF?

Anyway….trees can’t die of old age either, I assume all plants may be like that, but that’s not my area of expertise. That a creature outside of the plant kingdom can in theory live forever is fascinating. Did they explain how the DNA of a crocodile does not degrade with cellular reproduction?

 

[oaktree]

Hi Sukerkin there are some interesting animals such as these:

Hydras and Turritopsis nutricula

http://en.wikipedia.org/wiki/Turritopsis_nutricula

http://en.wikipedia.org/wiki/Hydra_(genus)

http://en.wikipedia.org/wiki/List_of_long-living_organisms

http://en.wikipedia.org/wiki/Biological_immortality

I hope you enjoy these links.

 

[Archangel M]

From what I understand our aging "problem" stems from errors in repeated cellular replication. Like a xerox of a xerox of a xerox, eventually the copy looses data.

 

[Sukerkin]

Aye, in part, replication errors are the cause of our increasing infirmity as we age.

What causes us to 'die' in the end is those errors plus the cumulative death and non-replacement of cells. Each cell has a number of times it can divide before it dies (there's a little 'timer' called a Telomere that determines this number).

If we can extend the number of repeated divisions each of cells does then we'll live longer. Of course, if we don't also attend to the replication errors then we'll live longer in more misery, which is not so good .

Whose our resident research biologist? Is it EH? I know we certainly have someone in the life sciences here at MT .

 

[oaktree]

The book the Immortal cell by Michael West is interesting read and the theory is interesting as well.

It would be nice of a Biologist to share his view on the extension of telomere and longer life as the book claims. From my limited understanding cancer cells have no telomere making them "immortal" if this is error I hope to be corrected of my ignorance.

http://en.wikipedia.org/wiki/Telomere

 

[Sukerkin]

I am not certain but I think what it is with cancer cells that makes them proliferate so is that they do not have a Suicide Gene, an 'off switch' usually fitted as standard to all our cells. I really am speaking from dimly remembered bits and pieces here so don't quote me .

 

[Xue Sheng]

I have just watched a lecture given by Professor Kaku on the 'near future' of technology.

Amidst all the physics talk that was sort of familiar because, oddly enough, of my taste for science fiction, something came out whilst he was speaking on the science of aging that quite set me back on my heels.

Apparently, there are some species of creature on Earth that do not die of old age! Crocodiles are one of them. They simply keep on getting bigger and bigger, not aging in a detrimental sense at all, until their environment can no longer sustain them.

Now starving to death is hardly a glamarous end for what seems to be an immortal organism but the very concept took my breath away.

They have found some snapping turtles...big snapping turtles... that are about 500 years old..... and when I heard that I thought much the same as you...they I thought you know that big nasty thing was likely here when Columbus bumped into America… I read that back in the early 90s by the way

 

[Empty Hands]

Whose our resident research biologist? Is it EH? I know we certainly have someone in the life sciences here at MT .

A couple, actually.

It is true that our lifespan is built into our DNA. A set lifetime is actually a survival benefit to the species because evolution is dependent on replicating generations, not immortal individuals, and immortal individuals suck up resources from replicating offspring. Thus, species with set lifespans are selected for by evolution, and nearly every species is thus limited. Our own hard set limit appears to be about 115 years.

We do have protective DNA capping sequences on the ends of the chromosomes called telomeres, which are successively lost with cell division. An enzyme called telomerase replaces the lost sequences in the gametes so that our offspring live a full lifespan. It should be possible through telomerase or other means to extend our lifespan. It may be challenging however, and the only sure method would be to perform DNA manipulation on fertilized embryos, which is problematic for obvious reasons.

Even with that basic change though, challenges would remain. For instance, the crosslinking and hardening of collagen fibers (hardening arteries, etc.) is a chemical process independent of genetic control. Diseases like cancer or Alzheimer's also appear to be inevitable diseases that not everyone gets because something else catches them first. These "wear and tear" type diseases and processes may not change with telomerase or other alterations. Thus, such individuals might make it later in life, but not as late as you might hope.

That said, the experimental evidence from animal models is quite compelling, and I have no doubt we could accomplish something along those lines. Sadly for us chubby Americans, significant caloric restriction is the easiest and one of the best life extenders we've discovered. Life extension is definitely possible and probably inevitable, although I do think that the big proponents and salesman of the topic are overselling, and in some cases fraudulent. Beware anyone trying to sell you testosterone or growth hormone as an anti-aging treatment.

 

[Empty Hands]

From my limited understanding cancer cells have no telomere making them "immortal" if this is error I hope to be corrected of my ignorance.

I am unaware of any cancer lines due to telomere changes, although I am not a cancer expert. Indeed, the DNA of cancer cells is often disordered and disregulated. More common are loss-of-function mutations in proteins that act as checkpoint breaks on cell division (i.e. p53, tumor suppressor genes), or gain-of-function mutations in proteins that promote cell division (i.e. Ras, tumor promoter genes). Or mutations in proteins that control and regulate the previous protein types. Telomeres protect the DNA from replication induced damage, they do not control cell division to my knowledge. Cancer is mainly a disease of cell division.

Other mutations are necessary too however. Every mole for instance is a benign tumor that has lost cell division control, like all benign tumors. Other mutations are necessary for metastatic cancer, including mutations to invade surrounding tissue, break off metastatic cells, invade blood vessels, and survive the death usually caused by being detached from other cells while they are floating in the blood (anoikis). That's why cancer is usually a disease of later life, it takes a while to accumulate the right mutations in the same cell population. That's also why mutagenic chemicals or radiation increase your chance of developing cancer.

 

[oaktree]

Hi Empty Hands thank you for the insightul posts!!

If I am reading correctly you are saying it is the cell division that makes it "immortal"
and not the non existance of telomere within the cell that make it "immortal"


I have seen the marketing salesmen have been doing the herb astragalus is being refered to as the herb that extends telomere and an extract can make you immortal with TA-65

http://www.tasciences.com/

I highly doubt this is true and I demand highlander type proof from this organization.

 

[Empty Hands]

Hi Empty Hands thank you for the insightul posts!!

You're welcome.

If I am reading correctly you are saying it is the cell division that makes it "immortal"
and not the non existance of telomere within the cell that make it "immortal"

Basically. "Immortal" means different things to the organism and to the individual cell. Immortal people never die, although individual cells within that person would constantly be dividing and dying. Immortal cells keep dividing, potentially forever, while individual cells in the group will die, indeed can die quite readily depending on the conditions. So uncontrolled cell division makes cells immortal, indeed cancerous, even though individual cancer cells die easily. What the telomere does is help prevent damage over repeated cell divisions, and thus has nothing to do with immortal cells per se, although it can help prevent damage over time in immortal cells. It's not necessary though because cancerous, immortal cells can sustain a lot of DNA damage and disregulation, and is indeed common in cancer cells.

I have seen the marketing salesmen have been doing the herb astragalus is being refered to as the herb that extends telomere and an extract can make you immortal with TA-65

Lies.

 

[David43515]

This whole thread has been interesting and thought provoking. I`ve learned alot....and I`m embarassed to admit that most of all it has given me an idea to throw into a fictional story. But it`s so cool to think about the variety of life on this rock.

I recall seeing a show here a few weeks ago that mentioned a small sea creature that gets old, condences, and expells an embrio that has 100% identical DNA and then dies. There`s no sexual reproduction, it`s basically immortal.

 

[oaktree]

To further add to the conversation,

He predicts that eventually a pill containing telomerase will be available for humans. It will reverse the signs of aging that have occurred and bring back a youthful vitality and appearance. The drug could be taken during the 40s or 50s to help impede the onset of serious illnesses like diabetes, Alzheimer's, and other diseases that occur most commonly in the elderly.

http://news.yahoo.com/s/ac/20101129...ging_will_an_antiaging_pill_be_available_soon

I am guessing science and biology has some interesting times ahead.

*note the quote above I had to edit a bit because some of the words were in code.

 

[MA-Caver]

Crocs (and presumably their kin) in the right environment would probably grow to gianormous proportions. Prehistoric crocs averaged well over 50 feet in length and scientists speculated they even took down the mighty T-Rex as it came to the river to drink.
Another remarkable thing about those creatures is that they can go for very long periods without food. So the idea of their "environment unable to sustain them" ... kinda puzzles me. Think of a nile croc waiting along a well used migration route/crossing. Lots of food there, no? Darwinism plays heavily along that scenario, wildebeasts and zebras crossing by the hundreds with little ones and old and sickly ones... even with competition from other crocs laying in wait... opportunities would abound one would think? All knowledge courtesy of Walt Disney & Marlin Perkins' Wild Kingdom episodes along of course with Attenborogh and the recent EARTH on the Discovery Channel as well as Animal Planet.

Gads I love learning!

 

[crushing]

According to Dr. Kaku's Facebook page:

Dr. Michio Kakuwill appear on MSNBC (Tuesday) at 11:10 am EST, talking about advances in controlling the aging process.

 

[Empty Hands]

I recall seeing a show here a few weeks ago that mentioned a small sea creature that gets old, condences, and expells an embrio that has 100% identical DNA and then dies. There`s no sexual reproduction, it`s basically immortal.

Plenty of species have asexual reproduction, or asexual reproduction during times of plenty and sexual reproduction during times of starvation and stress. This gets again as to what the word "immortal" means exactly. We know what it means for big multicellular organisms like ourselves, but the definitions become fuzzy at the cellular level. "Immortal" cells to a scientist means that the cell line keeps dividing, not that any individual cell is immortal. Yet can an identical daughter cell be considered a new stage of the same organism "individual", or is each new identical daughter cell a new "individual"? Scientifically the question is meaningless, but it's kind of interesting to think about nonetheless. It gets at old questions of identity.