Just remembering how cold things were can speed up the metabolism.
Your Back Page scribbler grew up in a cold climate.
The childhood town was located at a latitude of nearly 46 degrees south and was populated primarily by settlers from Scotland who seemingly found the inclement weather a nostalgic reminder of their rainswept homeland.
If your youthful correspondent had a dollar for every time he heard someone say “It would be a lovely day out there if it wasn’t for that bitterly cold wind”, he’d have been a very wealthy man.
It would be fair to say the bracing environment deeply embedded itself into the memory banks, but it is possible that those sub-zero winters and non-existent summers may also have become embedded in the metabolism as well.
That’s if new research by boffins at the University of Melbourne and Trinity College, Dublin, holds as true for humankind as it does for mice.
Publishing in the journal Nature, the scientists say their study has found that just the memory of cold temperatures can change the body’s metabolism and temperature regulation, even when the environment is no longer cold.
What the researchers did was to put mice in an environment where the temperature was only 4C so that the mice learned to associate that environment with cold temperatures. The mice increased their metabolic rate to cope with the chilly conditions.
They then returned the mice to the same environment but with the temperature set at a more pleasant 21C.
Interestingly, the team found the mice retained their higher metabolic rate and body temperature in that environment despite the warmer conditions, suggesting they had changed their body’s temperature regulation in response to the “memory” of the cold alone.
Which is all very well, but could this knowledge translate into something that could be usefully applied to non-rodent populations, such as Homo sapiens?
Yes indeed, our scientists say. In fact, these findings could inform potential treatment possibilities for metabolic diseases.
“In humans, altered metabolism in brown adipose tissue has been associated with cardiometabolic health,” the researchers say in their paper.
“In this study, we aimed to understand how the brain affects basic bodily functions with the additional goal of identifying therapeutic targets that would enable more-targeted treatments for cardiometabolic diseases in the future.
“For example, we showed that by stimulating engram cells [neurons that are active during encoding and retrieval of memory] in the brain, we were able to upregulate thermogenesis genes in brown adipose tissue.”
Current technological advancements in optogenetics meant this line of research opened interesting avenues for new therapeutic approaches, they added.
It’s comforting to think that those early years spent enduring bone-chilling southerly busters and sleet-laden squalls in the middle of an alleged summer were more than just character-building experiences.
Not comforting enough to make us want to ever return to living in that climate, however.
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