Posts tagged salamanders
Articles and news from the latest research reports.
Limb regeneration: do salamanders hold the key?
For the first time, researchers have found that the ‘ERK pathway’ must be constantly active for salamander cells to be reprogrammed, and hence able to contribute to the regeneration of different body parts.
The team identified a key difference between the activity of this pathway in salamanders and mammals, which helps us to understand why humans can’t regrow limbs and sheds light on how regeneration of human cells can be improved.
The study published in Stem Cell Reports, demonstrates that the ERK pathway is not fully active in mammalian cells, but when forced to be constantly active, gives the cells more potential for reprogramming and regeneration. This could help researchers better understand diseases and design new therapies.
Lead researcher on the study, Dr Max Yun (UCL Institute of Structural & Molecular Biology) said: “While humans have limited regenerative abilities, other organisms, such as the salamander, are able to regenerate an impressive repertoire of complex structures including parts of their hearts, eyes, spinal cord, tails, and they are the only adult vertebrates able to regenerate full limbs.
We’re thrilled to have found a critical molecular pathway, the ERK pathway, that determines whether an adult cell is able to be reprogrammed and help the regeneration processes. Manipulating this mechanism could contribute to therapies directed at enhancing regenerative potential of human cells.”
The ERK pathway is a way for proteins to communicate a signal from the surface of a cell to the nucleus which contains the cell’s genetic material. Further research will focus on understanding how this important pathway is regulated during limb regeneration, and which other molecules are involved in the process.
(Source: ucl.ac.uk)
Do salamanders hold the solution to regeneration?
Salamanders’ immune systems are key to their remarkable ability to regrow limbs, and could also underpin their ability to regenerate spinal cords, brain tissue and even parts of their hearts, scientists have found.
In research published today in the Proceedings of the National Academy of Sciences researchers from the Australian Regenerative Medicine Institute (ARMI) at Monash University found that when immune cells known as macrophages were systemically removed, salamanders lost their ability to regenerate a limb and instead formed scar tissue.
Lead researcher, Dr James Godwin, a Fellow in the laboratory of ARMI Director Professor Nadia Rosenthal, said the findings brought researchers a step closer to understanding what conditions were needed for regeneration.
"Previously, we thought that macrophages were negative for regeneration, and this research shows that that’s not the case - if the macrophages are not present in the early phases of healing, regeneration does not occur," Dr Godwin said.
"Now, we need to find out exactly how these macrophages are contributing to regeneration. Down the road, this could lead to therapies that tweak the human immune system down a more regenerative pathway."
Salamanders deal with injury in a remarkable way. The end result is the complete functional restoration of any tissue, on any part of the body including organs. The regenerated tissue is scar free and almost perfectly replicates the injury site before damage occurred.
"We can look to salamanders as a template of what perfect regeneration looks like," Dr Godwin said.
Aside from “holy grail” applications, such as healing spinal cord and brain injuries, Dr Godwin believes that studying the healing processes of salamanders could lead to new treatments for a number of common conditions, such as heart and liver diseases, which are linked to fibrosis or scarring. Promotion of scar-free healing would also dramatically improve patients’ recovery following surgery.
There are indications that there is the capacity for regeneration in a range of animal species, but it has, in most cases been turned off by evolution.
"Some of these regenerative pathways may still be open to us. We may be able to turn up the volume on some of these processes," Dr Godwin said.
"We need to know exactly what salamanders do and how they do it well, so we can reverse-engineer that into human therapies."
(Source: monash.edu)