Anti-aging science
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17-02-2014, 01:43 AM
RE: Anti-aging science
The mechanism with which NAD is proposed to counter ageing is via the mitochondrial pathway. I don't find NAD as a supplement convincing. The mitochondrial theory of aging is quite established.

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17-02-2014, 05:04 AM
RE: Anti-aging science
(16-02-2014 06:35 AM)Youkay Wrote:  1) The experiment with Drosophila was this: They strictly controlled the time point at which Drosophila would mate by delaying the age of reproduction as much as possible. What they have found is that the later the Drosophila were allowed to reproduce, the longer the life span of the offspring became.

What do you think does that experiment tell us?




2) The model was a nematode, a worm. What this study shows is "proof of principle". Yes, by exposing them to quite high concentrations of EUK-134 -a polycyclic, synthetic molecule which catalyses the same reaction as catalase and superoxide dismutase- the life span of nematodes increased slightly.

[Image: 5602197f6.gif]

What do you think might be valid criticism towards the experimental results and against this approach to prevent aging in humans?


Does any of you want to give it a try and answer those two questions? Or would you like me to answer? Those questions aim at understanding and criticizing experimental results, which is crucial in evaluating scientific claims.

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17-02-2014, 09:52 AM
RE: Anti-aging science
(17-02-2014 05:04 AM)Youkay Wrote:  2) The model was a nematode, a worm. What this study shows is "proof of principle". Yes, by exposing them to quite high concentrations of EUK-134 -a polycyclic, synthetic molecule which catalyses the same reaction as catalase and superoxide dismutase- the life span of nematodes increased slightly.

[Image: 5602197f6.gif]

What do you think might be valid criticism towards the experimental results and against this approach to prevent aging in humans?


Does any of you want to give it a try and answer those two questions? Or would you like me to answer? Those questions aim at understanding and criticizing experimental results, which is crucial in evaluating scientific claims.


Firstly, nematodes aren't humans so it might not work at all in humans. Secondly, this tells us nothing of the safety of this particular compound. Third, to achieve the concentrations of this experiment may be completely unfeasible in humans even if it were a good idea. But beyond that, I don't understand the biology, or even what most of these terms mean. This is the problem of the layman, and what makes it so hard to sort what's real from snake oil.

edit: I don't know what the y label on this graph means. Presumably, the x axis is UV-B exposure, but I also don't know what normal levels are.

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17-02-2014, 11:23 AM
RE: Anti-aging science
Your initial three points are very valid criticisms.

Regarding the diagram: The y axis indicates the lifespan of the nematodes in a percentage. The x axis indicates the UV dosage. The different colored bars indicate different concentrations of the anti-oxidant (0, 5 and 50 micromolar). And the lines that are drawn on top of the bars are error bars that indicate the standard deviation of measurements.

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17-02-2014, 01:02 PM
RE: Anti-aging science
(17-02-2014 05:04 AM)Youkay Wrote:  Does any of you want to give it a try and answer those two questions? Or would you like me to answer?

Now you are just being patronizing. You can do this without being a Chippy dick. Thumbsup

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17-02-2014, 08:31 PM
RE: Anti-aging science
I didn't mean to. The demand from other forum members was to have tools to read through scientific findings and being able to question them independently. I'm trying to give an example using 2 experiments mentioned in that review, which I think is a good way of learning how to read and interpret experimental results. Alternatively I could write down everything myself, but I don't see who would benefit from that.

You are free to distance yourself from my questions, but I'm glad that Toadaly actually came up with three quite valid criticisms and honestly said he wouldn't know what the diagram means.

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21-02-2014, 05:37 AM
RE: Anti-aging science
Toadaly, since I haven't received an answer regarding the diagram, I will just go ahead and explain it myself:

5 µM is a feasible concentration, whereas 50 µM is artificially high. For natural UV dosages (8 mJ/cm^2) the difference between untreated nematodes and nematodes treated with 5 µM EUK-134 is neglectable, especially when error bars are considered (have a look at the diagram and compare the 2nd set of columns, dark grey and white). For artificially high UV dosages (24 mJ/cm^2) the difference becomes clearly discernable (compare the 4th set of column, dark grey and light grey)

This experiment is a "proof of concept". Yes, EUK-134 can prevent UB radiation damage. Judging from this experiment alone, it is unclear through which mechanism EUK-134 impedes UV induced lifespan shortening. Therefore, other experiments were performed and presented in the very same paper to pin down the true mechanism.

However, EUK-134 shows distinguishable effects only at artificially high concentrations and UV dosages, which are completely irrelevant to normal conditions. Therefore, the findings have very little to no significance for anti-aging treatment.



This is how scientist approach experimental findings, with a lot of criticizm. We always ask "What is this result really telling us? What might be wrong with the conclusion?" and actively search for a possible answer. I hope this example has a value for your "education" (I do not want to assume to be educating you) in these things.

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