Results 1 to 7 of 7
  1. #1
    Join Date
    Mar 2011
    Location
    Western WA
    Posts
    5,508

    Default Article: Bone, not adrenaline, drives fight or flight response

    Practically speaking, this doesn't change our strategies, tactics or techniques to deal with violent encounters. Nor does it change how we train for such events. But it is interesting and makes me wonder where this line of inquiry will lead. Supplements or treatments that might enhance the warrior's reaction and response time? Or perhaps increased ability to harness the benefits of that "adrenal dump" without losing dexterity/fine motor control?

    If nothing else, we'll need a different phrase for "adrenal dump".

    Here's the whole article:

    When faced with a predator or sudden danger, the heart rate goes up, breathing becomes more rapid, and fuel in the form of glucose is pumped throughout the body to prepare an animal to fight or flee.



    These physiological changes, which constitute the "fight or flight" response, are thought to be triggered in part by the hormone adrenaline.

    But a new study from Columbia researchers suggests that bony vertebrates can't muster this response to danger without the skeleton. The researchers found in mice and humans that almost immediately after the brain recognizes danger, it instructs the skeleton to flood the bloodstream with the bone-derived hormone osteocalcin, which is needed to turn on the fight or flight response.


    "In bony vertebrates, the acute stress response is not possible without osteocalcin," says the study's senior investigator Gérard Karsenty, MD, Ph.D., chair of the Department of Genetics and Development at Columbia University Vagelos College of Physicians and Surgeons.
    "It completely changes how we think about how acute stress responses occur."


    Why Bone?


    "The view of bones as merely an assembly of calcified tubes is deeply entrenched in our biomedical culture," Karsenty says. But about a decade ago, his lab hypothesized and demonstrated that the skeleton has hidden influences on other organs.


    The research revealed that the skeleton releases osteocalcin, which travels through the bloodstream to affect the functions of the biology of the pancreas, the brain, muscles, and other organs.


    A series of studies since then have shown that osteocalcin helps regulate metabolism by increasing the ability of cells to take in glucose, improves memory, and helps animals run faster with greater endurance.


    Why does bone have all these seemingly unrelated effects on other organs?


    "If you think of bone as something that evolved to protect the organism from danger—the skull protects the brain from trauma, the skeleton allows vertebrates to escape predators, and even the bones in the ear alert us to approaching danger—the hormonal functions of osteocalcin begin to make sense," Karsenty says. If bone evolved as a means to escape danger, Karsenty hypothesized that the skeleton should also be involved in the acute stress response, which is activated in the presence of danger.


    Osteocalcin Necessary to React to Danger


    If osteocalcin helps bring about the acute stress response, it must work fast, in the first few minutes after danger is detected.


    In the new study, the researchers presented mice with predator urine and other stressors and looked for changes in the bloodstream. Within 2 to 3 minutes, they saw osteocalcin levels spike.


    Similarly in people, the researchers found that osteocalcin also surges in people when they are subjected to the stress of public speaking or cross-examination.
    When osteocalcin levels increased, heart rate, body temperature, and blood glucose levels in the mice also rose as the fight or flight response kicked in.


    In contrast, mice that had been genetically engineered so that they were unable to make osteocalcin or its receptor were totally indifferent to the stressor. "Without osteocalcin, they didn't react strongly to the perceived danger," Karsenty says. "In the wild, they'd have a short day."


    As a final test, the researchers were able to bring on an acute stress response in unstressed mice simply by injecting large amounts of osteocalcin.


    Adrenaline Not Necessary for Fight or Flight


    The findings may also explain why animals without adrenal glands and adrenal-insufficient patients—with no means of producing adrenaline or other adrenal hormones—can develop an acute stress response.


    Among mice, this capability disappeared when the mice were unable to produce large amounts of osteocalcin.


    "This shows us that circulating levels of osteocalcin are enough to drive the acute stress response," says Karsenty.


    Physiology the New Frontier of Biology


    Physiology may sound like old-fashioned biology, but new genetic techniques developed in the last 15 years have established it as a new frontier in science.


    The ability to inactivate single genes in specific cells inside an animal, and at specific times, has led to the identification of many new inter-organ relationships. The skeleton is just one example; the heart and muscles are also exerting influence over other organs.


    "I have no doubt that there are many more new inter-organ signals to be discovered," Karsenty says, "and these interactions may be as important as the ones discovered in the early part of the 20th century."


    The study, "Mediation of the acute stress response by the skeleton," was published Sept. 12 in Cell Metabolism.



    https://phys.org/news/2019-09-bone-a...-response.html
    Brent Yamamoto
    Suarez International Tier 1 Staff Instructor

    Ready, willing, able. Bring it.

    Instagram: karate_at_1200fps

    Upcoming classes:

    Advanced Close Range Gunfighting - Nov 2-3 Mapleton, OR

  2. #2
    Join Date
    Mar 2011
    Location
    Western WA
    Posts
    5,508
    I also wonder if differences in the levels or quality of osteocalcin might have behavioral and personality ramifications.

    Perhaps those who are inclined to hyperventilating at the mere image of an AR15 produce osteocalcin differently, or in different quantity.

    How does lifestyle and training effect it? Does training impact this physiological response? How does diet impact it?

    Interesting stuff.
    Brent Yamamoto
    Suarez International Tier 1 Staff Instructor

    Ready, willing, able. Bring it.

    Instagram: karate_at_1200fps

    Upcoming classes:

    Advanced Close Range Gunfighting - Nov 2-3 Mapleton, OR

  3. #3
    Join Date
    Dec 2003
    Location
    In a positive state of mind
    Posts
    3,649
    Quote Originally Posted by Brent Yamamoto View Post
    I also wonder if differences in the levels or quality of osteocalcin might have behavioral and personality ramifications.

    Perhaps those who are inclined to hyperventilating at the mere image of an AR15 produce osteocalcin differently, or in different quantity.

    How does lifestyle and training effect it? Does training impact this physiological response? How does diet impact it?

    Interesting stuff.
    Those are all good questions, and the subject of on-going research I expect.

  4. #4
    Join Date
    Jul 2017
    Posts
    28
    Wonder why there was no mention of the freeze response which I believe is the third possible reaction to danger - not necessarily the best. But it is there.

  5. #5
    Join Date
    Aug 2014
    Posts
    3,177
    Launching from Brent's comment:

    Does osteocalcin become depleted? Short-term? Long-term? With what effect? And can it be replaced, or increased, by diet or drugs--or, for that matter, diminished by the abuse of either?

    More coffee needed.
    Warrior for the working day.

    Es una cosa muy seria. --Robert Capa

    "...I ride the range in a Ford V8...Yippy Yi Yo Ki Yay." --Johnny Mercer

    "Can I move?...I'm better when I move."

    1, 1, 11. And a wakeup.

  6. #6
    Join Date
    Nov 2018
    Posts
    234
    Now this is interesting, but something I will have to address on the weekend, despite my 20-oz. latte with four shots of espresso from this afternoon.

  7. #7
    Join Date
    Nov 2009
    Posts
    139
    This research shows that the human body is more complex and adaptable that we previously thought. I think the take-away is that muscular AND skeletal health will go a long way in supporting you in stressful situations.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •