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…
(study abstract here: http://jap.physiology.org/content/112/1/33.abstract?etoc )