How Roundworms Regrow Brain Cells

Understanding how roundworms regrow severed nerves could one day lead to nerve injury treatments for humans.

AsianScientist (Oct. 19, 2016) – Researchers in Japan have detailed molecular mechanisms behind the regrowth of severed nerves in roundworms, which could lead to treatments promoting recovery from nerve injuries in humans. The article was published in The Journal of Neuroscience.

Neurons communicate with each other via electrical signals conveyed through dendrites and axons. Certain types of nerve injury, such as those from automobile accidents and falls, can damage or sever the axons that connect neurons and allow them to communicate with each other. Although axons elsewhere in the body can regenerate to some extent after such damage, those in nerves are far less capable, resulting in long-lasting or permanent impairment.

Interestingly, a non-parasitic, free-living roundworm nematode is a useful model for studying nerve regeneration after nerve injury; it not only has simple development and a short life cycle, but also helps researchers avoid the ethical problems associated with human experimentation.

The researchers investigated various strains of the roundworm in which different genes were mutated or inactivated. They then subjected the worms to a range of experiments, including labeling nerves, cutting them with a laser, and then monitoring their regrowth under a microscope.

The team found that when certain proteins encoded by these genes were absent or dysfunctional in the worms, their nerves were less able to regenerate, particularly during adulthood. By comparing these results among the strains in which single or multiple genes had been inactivated, the researchers established a complex molecular pathway that allows nerves to regenerate. They also found that the key molecular machinery involved in this regeneration behavior is the same as that by which dying cells are recognized, engulfed by immune system cells, and disposed of.

“Many of the molecules and mechanisms we identified in worms have equivalents in humans,” corresponding author Dr. Naoki Hisamoto said. “Our findings should therefore lead us to targets in humans that we can use to improve recovery after nerve injury by promoting regrowth of damaged axons.”



The article can be found at: Pastuhov et al. (2016) The Core Molecular Machinery Used for Engulfment of Apoptotic Cells Regulates the JNK Pathway Mediating Axon Regeneration in Caenorhabditis Elegans.

———

Source: Nagoya University.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Asian Scientist Magazine is an award-winning science and technology magazine that highlights R&D news stories from Asia to a global audience. The magazine is published by Singapore-headquartered Wildtype Media Group.

Related Stories from Asian Scientist