THE body’s ability to heal itself partly depends on natural electric fields, it has been proved for the first time. The work could lead to the development of drugs that speed up healing by enhancing these natural fields.
Cell migration and division plays a key role in development and healing. Most research in this area is on chemical factors, but several studies have shown that applying electric fields can affect migration and division as well. After successful trials in animals, for example, a team in the US is trying to encourage the healing of spinal cord injuries by applying an external field.
To discover whether the body’s natural electric fields play a role in healing, Colin McCaig’s team at the University of Aberdeen in Scotland looked at rat corneas. In an undamaged cornea, cells pump positively charged ions into the cornea and push negatively charged ions out, creating an electrical potential of 40 millivolts. But in damaged areas this voltage disappears, setting up an electric field between damaged and intact areas that stretches for half a millimetre along the surface of the injured cornea.
The researchers used a variety of chemicals to nullify or enhance this natural field. Dividing cells tended to line up at right angles to the field. But when the fields were nullified, the cells aligned randomly, they report in Proceedings of the National Academy of Sciences (DOI:10.1073/ pnas202235299). McCaig says that the electric field may attract positively charged proteins or lipids in the membranes of cells.
What’s more, the team found that healing was faster when the field was boosted, and slower when it was decreased. Stronger fields also encourage cells to divide, though how they do this isn’t clear.
McCaig says the work is the first demonstration that the body’s natural electric fields play a key role in healing. “It’s a big step forward to help biologists believe that the fields are important.”
It’s possible that drugs could be developed that enhance the natural field around wounds, boosting healing. This may prove more effective than applying an external field that doesn’t have the same shape as a natural field.