Altitude babies, Rats, and Epigenetics

New born rats, altitude, and epigenetics:

Over the past few years, the term epigenetics has kind of exploded in the popular science world.  I’ve discussed it at length in this blog and how it might have implications with a wide range of topics from obesity to African running dominance to how we adapt to altitude.
One of the basic ideas is that what happens in the time period before and just after birth is when a newborn is kind of adapting to its adjustment.  So if we look at diet, if a mother is going through famine during this time frame, then the baby changes to be prepared for this environment.  So it’s response to certain foods or its insulin response is adjusted.  Similarly, there’s been some studies looking at mothers who have high stress loads during and right after pregnancy result in babies have altered stress hormone responses for the rest of their life.
I always joke with my friends that whenever I have kids, I’m going to stick them at altitude during pregnancy and right after just to develop super altitude adapted kids (and my friends always respond with you better find a wife who is crazy enough to let you do all this wonderful experimentation…and that you’re kids are gonna be messed up…but that’s besides the point…).  Which brings me to the point of this…
A study in the Journal of Applied Physiology was recently published that took a bunch of rats that were at high altitude in Bolivia and made a group of them live in a simulated sea level environment.  So you basically had an altitude group and a sea level group, but it was only from 1 day before birth to 15 days after birth when they were in these two different environments.  Then they were brought together and lived their normal rat lives together.  Well, they checked them periodically through their life and ultimately at 600 days post birth. 
What is interesting is that those 16 days during development affected parameters for the rest of their lives.  For example, the “normoxia/oxygen” group had lower hemoglobin and hematocrit for the rest of their lives.  They also had “reduced right ventricular hypertrophy (both sexes); lower air space-to-tissue ratio in the lungs (males only); reduced CO2 production rate, but higher oxygen uptake (males only);”
It’s pretty interesting that 16 days in the rat lifecycle affected various parameters for the rest of their lives.  It just goes to show how important that development period actually is and it brings up some questions about altitude training and whether just copying altitude born athletes is the key or if we should attack it from a different way with sea level born athletes.
I’m not really sure what the practical importance of this is, except maybe my crazy joking of having high altitude babies might be on to something…

5 comments:

  1. I think Steve maybe you should take an interest in quantum physics, then you will understand that by just even watching an experiment you can have a dramatic change to the outcome of said experiment!

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  2. I find this particularly interesting, especially in regards to my second child, with whom I gestated at 9000ft. She lived at that altitude for her first year... I think she'll be a phenomenal runner if that's the path she chooses. If that's the case, you can use her in your future blogs... :)

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  3. Cool article, thanks -- I've loosely been involved with research on perinatal cardiac development and hypoxia.

    I know your comments about raising hypoxic children(!) are tongue-in-cheek (I'm always proposing similar ridiculous experiments to my exasperated wife), but the conclusion in the abstract (sadly, I don't have access to that journal) is
    "We conclude that exposure to ambient hypoxia during postnatal development in HA rats has deleterious consequences on acclimatization to hypoxia as adults."

    The first year of life is very sensitive to oxygen, as the heart switches over from it's fetal gene programming to using new metabolic substrates. In general, elevation has been shown to increase infant mortality, and is theorized to be involved in SIDs, as cardiac development is impaired. (The research I'm talking about is significantly higher than 9k feet, also -- not to suggest anything otherwise with respect to the numerous healthy babies born all over Colorado to active skiing/hiking Mom's!). 16 days in rats does seem remarkable. Human cardiac development is considered critical in the first 6-12 months, so given that humans live ~20x as long as rats, that makes for an interesting comparison.

    So you're absolutely right about the importance of epigenetics: the heart happens to be a particular organ that is particularly sensitive to the environment in a short amount of time, especially post-natally. And I think your suggestion that high-altitude vs. sea-level-born athletes might benefit from training differently than each other is particularly insightful and novel. Otherwise, *purposely* taking newborns to high elevations has only been shown to be *harmful*, in this study and others.

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  4. let us time travel backwards and relive those first 16 days..facinating

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  5. Anonymous9:47 AM

    Completely off topic here Steve, but I didn't know how to get the question to you...what are your thoughts about respiratory training. The powerbreathe or power lung....worth it? What if you suspect you may have minor EIAH...read about that in your book?

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