MAR 14, 2018 3:58 PM PDT

Gaining Insight Into Death Through Worm Rigor Mortis

WRITTEN BY: Carmen Leitch

Researchers have found that worms experience rigor mortis before, rather than after death as humans do. The study is the first to observe rigor mortis in worms and provides a little insight into the biological processes experienced by an organism when it dies. The international team of scientists from Washington University and UCL used the C. elegans roundworm to learn a bit more about death from old age, something that is not well understood. Their findings have been reported in Cell Reports.

This is cellular necrosis in C. elegans. / Credit: David Gems, UCL

"Cell death has been widely studied but much less is known about [the] death of whole organisms, how it happens, what triggers it, and when it begins and ends. But it's extremely important for understanding fatal diseases in humans, especially those caused by aging," said research leader Professor David Gems of the UCL Institute of Healthy Aging.

Death is defined by a lack of heart or brain function; when it ceases, an organism is considered dead. But there are many physiological events before and after death. In C. elegans, cell death spreads through the animal. As a cell dies, it triggers the death of neighboring cells by releasing calcium. The process starts with muscles, causing hypercontraction and rigor mortis.

"The way death spreads from cell to cell by calcium is like a house burning down," explained lead author Dr. Evgeniy Galimov, of the UCL Institute of Healthy Aging.

When a person dies, stiffness sets in. That rigor mortis in followed necrotic degeneration and muscles get soft again. That process is a consideration in the meat industry; the product has to be tender. It can also help forensic studies that seek to establish a time of death. C. elegans undergo a similar series of contraction and relaxation in their muscles as they die.

"What really surprised us at first was that rigor mortis in worms begins while they are still alive. But then we realized that death from circulatory failure, as in mammals, doesn't happen in C. elegans. The worms are so small they don't need a circulatory system to get oxygen for respiration," explained Dr. Galimov.

"Dying C. elegans also undergo what we term a 'belly punch' phenomenon where death contraction in the head drives the pharynx backward into the intestine, and the impact triggers cell death," noted Professor Gems.

This work, which you can learn more about from the video above, suggests that declines that are a hallmark of old age may be due to an inability to generate cellular fuel, ATP. That leads to a failure to contain calcium within the cell. When it is released, it causes cellular necrosis. 

"Discovering rigor mortis in worms is exciting as it highlights a key step in the chain of events leading from healthy adulthood to death from old age. It helps us to understand death in humans, and perhaps in the future to prevent death in mortally ill patients," concluded Professor Gems.


Sources: AAAS/Eurekalert! Via University College London, Cell Reports

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
NOV 17, 2020
Genetics & Genomics
Why Mutations in RRP7 Cause a Congenital Brain Disorder
NOV 17, 2020
Why Mutations in RRP7 Cause a Congenital Brain Disorder
A large family with some members that have a rare brain disorder has helped scientists learn more about both brain devel ...
NOV 19, 2020
Cell & Molecular Biology
A Different View of Chromosomes
NOV 19, 2020
A Different View of Chromosomes
Many of us are familiar with typical diagrams of a chromosome, which is usually drawn like a stubby X. While that pictur ...
DEC 03, 2020
Space & Astronomy
Health Issues from Spaceflight Caused by Mitochondria
DEC 03, 2020
Health Issues from Spaceflight Caused by Mitochondria
Spending an extended time in space is known to impact various aspects of health, from muscle and bone regeneration to th ...
JAN 12, 2021
Cardiology
SGLT2 Inhibitors Can Reduce the Cardiovascular Risk for Diabetics Being Treated with Insulin
JAN 12, 2021
SGLT2 Inhibitors Can Reduce the Cardiovascular Risk for Diabetics Being Treated with Insulin
One of the biggest problems that come alongside diabetes is the increased risk of cardiovascular disease. Treatment of d ...
JAN 11, 2021
Cell & Molecular Biology
Ginger May Help Slow Lupus or Antiphospholipid Syndrome Progression
JAN 11, 2021
Ginger May Help Slow Lupus or Antiphospholipid Syndrome Progression
Naturally occurring chemicals make more appealing medicines for many people, but there is not always evidence that they' ...
JAN 15, 2021
Genetics & Genomics
Rare Quadruple Helix DNA Found in Live Human Cells
JAN 15, 2021
Rare Quadruple Helix DNA Found in Live Human Cells
Many people picture the classic double-stranded helix when picturing a molecule of DNA, but DNA is also capable of formi ...
Loading Comments...