Research sheds light on how the "flight-or-flight" response impairs long-term organism health. The study, conducted in the nematode worm, C. elegans, a common research model, was published in Nature.
When humans perceive a dangerous or stressful situation, the body releases stress hormones such as adrenalin. Adrenaline makes the heart beat faster, increases blood flow to the brain and muscles, and stimulates the body to make sugar to use for fuel. The rush of adrenaline triggers the "fight-or-flight" response which gives the person the ability to escape a predator or respond to a threat.
Animals are exposed to different forms of stress. These can be abrupt, such as the appearance of a predator, or more progressive, like chronic food shortage, high temperatures, or oxidation.
"Much like in humans, repeated activation of the flight response in C. elegans drastically shortened lifespan," said the grad student. "The flight response is crucial for the worm to escape from predators. But we find there is a cost; the repeated activation of the flight response reduces the worm's capacity to deal with other challenges it encounters in its environment."
In the study, investigators found that the flight response in C. elegans triggers the activation of a single pair of neurons that release tyramine, the invertebrate analog of adrenaline and precludes the induction of stress response genes by activating an adrenergic-like receptor in the intestine. In contrast, exposure to long term environmental challenges such as heat and oxidative stress reduces tyramine release and thereby allow the induction of cytoprotective genes. This stress hormone thus provides a switch that regulates the animal's response to either acute or long-term stressors.
The researchers went on to show that tyramine stimulates the insulin pathway through the activation of an adrenergic-like receptor in the intestine. The activation of the insulin pathway can satisfy the animal's energy demands of the flight response. On the other hand, the down-regulation of the insulin pathway is needed help to protect cells from environmental stress and extend lifespan.
"This shows how a dynamic regulation of a stress neurohormone regulates the trade-off between acute and long-term stress responses," said the senior author. "The worm never ceases to amaze me; it keeps revealing fundamental molecular and neural mechanisms that may underlie even extremely complex human biology and disorders. Given the striking conservation of stress response mechanisms from worms to humans, it will be very interesting to see whether in humans the fight-or-flight response and stress neurohormones negatively impact health and aging through the activation of the insulin pathway."
https://www.nature.com/articles/s41586-019-1524-5
How stress can weaken defenses
- 1,730 views
- Added
Edited
Latest News
Complete vascularization of…
By newseditor
Posted 28 Mar
Immune cells identified as…
By newseditor
Posted 28 Mar
TB blood test which could d…
By newseditor
Posted 27 Mar
Propionate supplementation…
By newseditor
Posted 27 Mar
Role of human Kallistatin i…
By newseditor
Posted 26 Mar
Other Top Stories
How mechanical forces nudge tumors toward malignancy
Read more
How cancer evades the immune system
Read more
Genes that drive ovarian cancer identified!
Read more
Neural Differentiation Defect from Loss of a Single Gene Fuels Dead…
Read more
How a protein mutation leads to colorectal cancer
Read more
Protocols
Spatial proteomics in neuro…
By newseditor
Posted 28 Mar
All-optical presynaptic pla…
By newseditor
Posted 23 Mar
Epigenomic tomography for p…
By newseditor
Posted 20 Mar
A mouse DRG genetic toolkit…
By newseditor
Posted 17 Mar
An optogenetic method for t…
By newseditor
Posted 13 Mar
Publications
A microfluidic platform int…
By newseditor
Posted 28 Mar
Salmonella manipulates macr…
By newseditor
Posted 28 Mar
BHLHE40/41 regulate microgl…
By newseditor
Posted 28 Mar
Balancing neuronal activity…
By newseditor
Posted 28 Mar
OSBP-mediated PI(4)P-choles…
By newseditor
Posted 28 Mar
Presentations
Hydrogels in Drug Delivery
By newseditor
Posted 12 Apr
Lipids
By newseditor
Posted 31 Dec
Cell biology of carbohydrat…
By newseditor
Posted 29 Nov
RNA interference (RNAi)
By newseditor
Posted 23 Oct
RNA structure and functions
By newseditor
Posted 19 Oct
Posters
A chemical biology/modular…
By newseditor
Posted 22 Aug
Single-molecule covalent ma…
By newseditor
Posted 04 Jul
ASCO-2020-HEALTH SERVICES R…
By newseditor
Posted 23 Mar
ASCO-2020-HEAD AND NECK CANCER
By newseditor
Posted 23 Mar
ASCO-2020-GENITOURINARY CAN…
By newseditor
Posted 23 Mar