Re:Dying Organs Restored to Life in Novel Experiments
by T-A on Monday July 16, 2018 @07:18AM
(#17540360)
It occurs to me that mitochondrial decline also seems to be an important aspect of aging. If you can just infuse mitochondria through the blood and "the organelles will gravitate almost magically to the injured cells that need them and take up residence", that suggests a rather obvious rejuvenation approach.
Re:Dying Organs Restored to Life in Novel Experiments
by Symmetry on Monday July 16, 2018 @12:46PM
(#17542711)
Yeah, Mitochondria are a big deal in aging. Animals of a given size with larger mitochondria populations, like hummingbirds, tend to live a lot longer than other animals of similar size. Though hummingbirds lose their ability to hover and hence feed normally in the wild long before they die of old age.
Nick Lane wrote about book about mitochondria I'd heartily recommend: Power, Sex, Suicide: Mitochondria and the Meaning of Life.
Re:Dying Organs Restored to Life in Novel Experiments
by ArtWomb on Monday July 16, 2018 @08:19AM
(#17540679)
Yup. It is a very promising area of rejuvenation research. I think right now most dollars are allocated to understanding basic mitochondrial function. As well as cures for the pernicious degenerative diseases associated with malfunctioning mitochondria that cruelly tend to develop in young children. But there is no question: further research activities and clinical trials have a high probability of bearing fruit. Cryo-EM visualization of metabolic pathways. Even understanding function and purpose of the THC cannabinoid receptors found on their outer membranes could unlock their mysterious hidden potential.
Re:Dying Organs Restored to Life in Novel Experiments
by nine_k on Monday July 16, 2018 @08:51AM
(#17540877)
Maybe from cloning one's own cells, then carefully dismantling them to free up mitochondria without damaging them? I don't think a lot of the tissue should be required (that is, ounces, not pounds).
Re:Dying Organs Restored to Life in Novel Experiments
by aldoushuxley001 on Monday July 16, 2018 @11:46AM
(#17542220)
It's true that they very much rely on a nuclear genome, because some of their genes required for independent replciation have been lost. But surely there's a framework that enables the mass replication of mitochondria using our own cells as a source material.
I doubt blood would work because red blood cells contain effectively very minimal, if not zero, mitochondria (depending on stage of cycle).
Funny enough, the best bet might be taking mitochondria from sperm or egg. Human sperm have ~50-75 mitochondria per cell. There's on average 50 million sperm cells per ml of ejaculant and the average is 2.5ml per ejaculation, so 125 million mitochondria could potentially be harvested from an average guy in a single go, provided the extraction is an unrealistic 100% efficiency.
Re:Dying Organs Restored to Life in Novel Experiments
by seandougall on Tuesday July 17, 2018 @10:39PM
(#17555218)
IANABiologist, but my understanding is that they don’t differentiate; they have too simplistic a structure for that, and rely on the host cells for many of their functions. The main differences seen across cell types is whether they are present or not.
Re:Dying Organs Restored to Life in Novel Experiments
by jhou2 on Monday July 16, 2018 @04:01AM
(#17539531)
A brief search shows that mitochondrial transplantation for myocardial infarction was described in 2008. Astonishing work. This is starting to become more mainstream in the last couple of years.
Re:Dying Organs Restored to Life in Novel Experiments
by cromwellian on Monday July 16, 2018 @12:45PM
(#17542698)
Wait, how do the mitochondria get back into the cells? Presumably the cell membrane somehow permits them to pass but how are they recognized? If a mechanism exists to recognize and permit them to move into a cell, doesn’t that either suggest they can move out of cells as well and/or confirm the theory that mitochondria were symbiotes? That is, there’s something in cell DNA that encodes a mechanism for foreign symbiotes to cross the cell membrane?
Re:Dying Organs Restored to Life in Novel Experiments
by 88e282102ae2e5b on Thursday July 19, 2018 @10:32AM
(#17566631)
I was also surprised by this. In the papers where they did this work, they discuss many previously-known mechanisms for intercellular mitochondrial transfer - apparently cells can form nanotubes and exchange organelles, and that's relatively well-studied. That's not what's happening here, though, and they state that the mechanism at play is unknown.
Re:Dying Organs Restored to Life in Novel Experiments
by JacobDotVI on Monday July 16, 2018 @11:48AM
(#17542234)
From Edward Tufte’s book “Data Analysis for Politics and Policy”:
“One day when I was a junior medical student, a very important Boston surgeon visited the school and delivered a great treatise on a large number of patients who had undergone successful operations for vascular reconstruction. At the end of the lecture, a young student at the back of the room timidly asked,
“Do you have any controls?” Well, the great surgeon drew himself up to his full height, hit the desk, and said, “Do you mean did I not operate on half of the patients?” The hall grew very quiet then. The voice at the back of the room very hesitantly replied, “Yes, that’s what I had in mind.” Then the visitor’s fist really came down as he thundered, “Of course not. That would have doomed half of them to their death.” It was quiet then, and one could scarcely hear the small voice ask, “Which half?””
Re:Dying Organs Restored to Life in Novel Experiments
by Engineering-MD on Monday July 16, 2018 @07:17AM
(#17540350)
In clinical trials, pure placebos are very rarely used (only in mild conditions or where no treatment exists). Commonly novel therapies are compared against the current treatment of choice.
Re:Dying Organs Restored to Life in Novel Experiments
by michaelscott on Monday July 16, 2018 @07:54AM
(#17540541)
I was about to ask how ethical it could be to give a pure placebo in cases as serious as heart failure, when simply telling the patient (or the patient's family) that they received some other more conventional procedure should produce similar results.
Re:Dying Organs Restored to Life in Novel Experiments
by nine_k on Monday July 16, 2018 @08:54AM
(#17540900)
I think this is never done. I suppose both groups receive two therapies, one of them being the best available therapy for the condition, and the other either the new therapy, or a placebo.
This requires new and old therapies to be compatible, though.
Nick Lane wrote about book about mitochondria I'd heartily recommend: Power, Sex, Suicide: Mitochondria and the Meaning of Life.
EDIT: And Aubrey de Grey of course has a typically audacious/crazy plan for dealing with mitochondrial mutations. http://www.sens.org/research/introduction-to-sens-research/m...
http://www.lifeextension.com/Magazine/2010/2/Reverse-Mitocho...
And if pounds are needed, well... let's just say there should be plenty of eager donors for those who don't have enough.
I doubt blood would work because red blood cells contain effectively very minimal, if not zero, mitochondria (depending on stage of cycle).
Funny enough, the best bet might be taking mitochondria from sperm or egg. Human sperm have ~50-75 mitochondria per cell. There's on average 50 million sperm cells per ml of ejaculant and the average is 2.5ml per ejaculation, so 125 million mitochondria could potentially be harvested from an average guy in a single go, provided the extraction is an unrealistic 100% efficiency.
So 6.25 billion potentially harvestable mitochondria per average sperm donation.
Hard to say how much might be needed for a rejuvination test, but those seem like viable numbers.
(Edit: except for cells that have no mitochondria, of course)
https://www.ncbi.nlm.nih.gov/pubmed/18978192
“One day when I was a junior medical student, a very important Boston surgeon visited the school and delivered a great treatise on a large number of patients who had undergone successful operations for vascular reconstruction. At the end of the lecture, a young student at the back of the room timidly asked, “Do you have any controls?” Well, the great surgeon drew himself up to his full height, hit the desk, and said, “Do you mean did I not operate on half of the patients?” The hall grew very quiet then. The voice at the back of the room very hesitantly replied, “Yes, that’s what I had in mind.” Then the visitor’s fist really came down as he thundered, “Of course not. That would have doomed half of them to their death.” It was quiet then, and one could scarcely hear the small voice ask, “Which half?””
https://www.edwardtufte.com/tufte/dapp/DAPP1.pdf
(further attributed to Dr. E. E. Peacock, Jr, as quoted in Medical World News, September 1, 1972, p. 45)
This requires new and old therapies to be compatible, though.
Could!!!
Work!!!!!!
(Apologies to Mel Brooks/Young Frankenstein)