MAR 14, 2018 03:58 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 28 peer-reviewed publications, traveler to over 60 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
NOV 19, 2018
Cell & Molecular Biology
NOV 19, 2018
How Mitochondria can Help the Cell Fight Pathogens
Some pathogens can get around out bodies' natural defense mechanisms. So our body developed a Plan B....
NOV 27, 2018
Genetics & Genomics
NOV 27, 2018
Researchers Stunned to Find People who Inherited Mitochondrial DNA From Dad
It was thought that in humans, mitochondrial DNA was passed on exclusively by mothers....
DEC 03, 2018
Neuroscience
DEC 03, 2018
Brain size and Intelligence
Identifying the connection between the brain size to smartness has become much more plausible due to accuracy in estimating the brain size by using technologically advanced neuroimaging metho...
DEC 07, 2018
Microbiology
DEC 07, 2018
Epigenetic Inheritance is Revealed in Archaea
Researchers may have found a great new way to study tags that are added to the genome, which change how genes are expressed....
DEC 14, 2018
Microbiology
DEC 14, 2018
Investigating Probiotics as a Potential Therapeutic for Bipolar Disorder
Our gastrointestinal system has a special relationship with our brain - they are connected in what's called the gut-brain axis....
DEC 15, 2018
Genetics & Genomics
DEC 15, 2018
Neanderthal Genes Provide Insight Into Human Brain Evolution
Neanderthal heads are almost football-shaped, while modern humans have much rounder brains and skulls....
Loading Comments...