Wednesday, February 22, 2017

Some Stress is Good, According to Worm Studies

We as humans all hate stress.  Stress can be annoying, whether it lies within schooling or social environments.  Nobody wants to be stressed out, and there are numerous ways in which to relieve stress.  However, according to a study done by the Sanford-Burnham Prebys Medical Discovery Institute, some stress can promote longevity.

Essentially, the study done focused on a specific process in the body called autophagy.  Autophagy, as defined by ScienceDaily, is a means of recycling cells' old, broken, or unneeded parts so that their components can be re-used to make new molecules or be burned for energy.  Granted, this has been proven before.  This isn't entirely new science that is being done here.  What this study proves is that long life and stress resistance are connected at a cellular level.  In order to prove this theory, the researchers used a different subject other than humans.  They used an animal that bears some resemblance to our own cellular level.  They, in fact, bear a stronger resemblance to us via DNA than one might think (which I may someday discuss in another topic).

It's a worm.  More specifically, Caenorhabditis elegans, which is a free living, transparent nematode.

"We used C. elegans -- tiny roundworms used to study fundamental biology -- to test the importance of autophagy in becoming stress resistant," says Caroline Kumsta, Ph.D., staff scientist in Hansen's lab and lead author of the study. "They're a great model system because they're transparent, so you can easily observe what goes on inside them, most of their genes and molecular signaling pathways have functional counterparts in humans, and they only live a few weeks, which greatly facilitate measuring their lifespans."  Granted, the worms used in this study were not presented with horrible conditions.  Simply raising the temperature to 36 degrees Celsius for one hour provided a small shock to the system.  The worms exposed went through autophagy to repair the cells damaged.  Again, they were exposed to another heat stress.  Worms that were unable to repair their cells or were deficient with completing autophagy sustained more damage than the worms who experienced autophagy successfully.

Secondly, the team set out to determine if this cellular function could help out with another issue due to old age.  By targeting these worms with heat stress, the researchers hoped to reduce aggregated proteins that build up in cells.  They used worms that were modeled after Huntington's disease, which is a fatal inherited disorder caused by neuronal proteins that start to stick together into big clumps as patients age that leads to degeneration throughout the brain.  After exposing the model worms to heat once more, the aggregated proteins were reduced in number as the body experienced autophagy again.  "Our finding that brief heat exposure helps alleviate protein aggregation is exciting because it could lead to new approaches to slow the advance of neurodegenerative diseases such as Huntington's," says Hansen.  "The results may also be relevant to Alzheimer's and Parkinson's, which are similarly caused by clumping-prone proteins."

Essentially, this experiment shows that mild stress induction can improve the body's longevity by causing the body to repair cells through autophagy.  Does this mean you need to sit in the sauna or do hot yoga at all times?  No, not necessarily.  But it is important to expose your body to some levels of stress in order to improve yourself.  Take for example, a runner.  As a runner progresses, they get better and better at running longer and longer distances.  Their lungs handle the run better each time.  This same idea applies to the body and the cells within you.  By exposing them to small stresses slowly over time, they repair through autophagy and can increase your longevity because your body is trying to adapt to the environment.  So go sit in the sauna every once in awhile.  Go for that run you keep telling yourself you're going to do.  Go lift weights or do yoga.  You're helping your body out by doing so.

The link to the published story by ScienceDaily can be found here:

https://www.sciencedaily.com/releases/2017/02/170215084050.htm

The link to the research paper for this topic published at Nature can be found here:

http://www.nature.com/articles/ncomms14337