Inproved repair to damage of the peripheral nervous system

Researchers from the Peninsula College of Medicine and Dentistry, University of Exeter, in collaboration with colleagues from Rutgers University, Newark and University College London, have furthered understanding of the mechanism by which the cells that insulate the nerve cells in the peripheral nervous system, Schwann cells, protect and repair damage caused by trauma and disease.

The findings of the study, published on-line by the and supported by the Wellcome Trust, are exciting in that they point to future therapies for the repair and improvement of damage to the .

The peripheral is the part of the nervous system outside the brain and the spinal cord. It regulates almost every aspect of our bodily function, carrying sensory information that allows us to feel the sun on our face and motor information, that allows us to move. It also controls the functions of all the organs of the body.

Damage can occur through trauma: it can occur in (suffered by almost half of those with diabetes) and patients with common inherited conditions such as Charcot-Marie-Tooth (CMT) disease. There can be a wide range of symptoms, from loss of sensation in the hands and feet to problems with digestion, , and bladder control.

provide the insulation, or myelin sheath, for the that carry to and from the spinal cord. Schwann cells, because of their plasticity, are able to revert back to an immature 'repair' cell to repair damage to the peripheral nervous system. The level of repair is remarkably good but incomplete repair, perhaps after the severance of a nerve, may lead to long-term loss of function and pain.

The ability of Schwann cells to demyelinate can make them susceptible to the disease process seen in conditions such as CMT. CMT affects one in 2500people, so is a comparatively common inherited disease of the nervous system. Mutations in the many different genes in CMT can cause cycles of repair and re-insulation (re-myelination) which lead to long-term damage and the death of both Schwann and nerve cells. There is currently no therapy for CMT and patients experience increased sensory and motor problems which may lead to permanent disability.

The research team believes that its work to understand the ability of Schwann cells to revert back to an immature state and stimulate repair will lead to therapies to improve damage from severe trauma and break the cycle of damage caused by CMT. They also believe that there may also be potential to improve repair in cases of diabetic neuropathy.

They have identified a DNA binding protein, cJun, as a key player in the plasticity that allows a Schwann cell to revert back to the active repair state. cJun may be activated by a number of pathways that convey signals from the surface of the Schwann cell to the nucleus. One such pathway, the p38 Mitogen Activated Protein Kinase Pathway, appears to play a vital role: it is activated after PNS damage and may promote the process of repair; conversely it may be abnormally activated in demyelinating diseases such as CMT.

Professor David Parkinson, Associate Professor in Neuroscience, Peninsula College of Medicine and Dentistry, University of Exeter, said: "The findings of our research are exciting because we have pinpointed and are understanding the mechanism by which our bodies can repair damage to the peripheral nervous system. With further investigation, this could well lead to therapies to repair nerve damage from trauma and mitigate the damage which relates to common illnesses, such as CMT."

add to favorites email to friend print save as pdf

Related Stories

Turning back the clock for Schwann cells

May 19, 2008

Myelin-making Schwann cells have an ability every aging Hollywood star would envy: they can become young again. According to a study appearing in the May 19 issue of the Journal of Cell Biology, David B. Parkinson (Unive ...

How injured nerves grow themselves back

Sep 27, 2010

Unlike nerves of the spinal cord, the peripheral nerves that connect our limbs and organs to the central nervous system have an astonishing ability to regenerate themselves after injury. Now, a new report in the October 1st ...

Scientists find gene vital to nerve cell development

Jun 09, 2011

(Medical Xpress) -- The body’s ability to perform simple tasks like flex muscles or feel heat, cold and pain depends, in large part, on myelin, an insulating layer of fats and proteins that speeds the ...

Recommended for you

Steering the filaments of the developing brain

19 hours ago

During brain development, nerve fibers grow and extend to form brain circuits. This growth is guided by molecular cues (Fig. 1), but exactly how these cues guide axon extension has been unclear. Takuro Tojima ...

Do we really only use 10% of our brain?

19 hours ago

As the new film Lucy, starring Scarlett Johansson and Morgan Freeman is set to be released in the cinemas this week, I feel I should attempt to dispel the unfounded premise of the film – that we only use 10% of our brains ...

Birthday matters for wiring-up the brain's vision centers

Jul 31, 2014

Researchers at the University of California, San Diego School of Medicine have evidence suggesting that neurons in the developing brains of mice are guided by a simple but elegant birth order rule that allows them to find ...

User comments