Electric field can help keep biological tissues functioning while stored in ice, a finding that could help boost the number of successful kidney transplants.
The approach seems effective in mice given transplants and in human kidneys stored for 24 hours – although it hasn’t yet been tried on organs put inside people.
It could be used on other transplanted organs and even tissues inside the body with low blood supply, says Ruisheng Liu at the University of South Florida in Tampa. “There are lots of possibilities.”
Kidney transplants can be life-saving, but some kidneys don’t function well after the surgery because they are damaged from lack of oxygen during transport.
Low oxygen stops kidney cells making enough of a compound called adenosine triphosphate (ATP), which normally powers a molecular pump on their surface that keeps sodium levels low and potassium levels high inside cells. The shutdown causes the cells to swell and damages many of their enzymes and other biochemicals.
But the molecular pumps are sensitive to electric field, and Liu’s group has found that putting electrodes on the surface of the kidney and applying an oscillating field can restart many of the cells’ pumps.
To test the approach, the researchers gave 10 mice a kidney transplant and stored the organs in cold saline before each was implanted. Seven of the mice that were given the electrical treatment had more than 50 per cent better kidney function than those that didn’t, as judged by a commonly used blood test.
They also tested the approach in five pairs of human kidneys that had been donated but weren’t in a good enough condition to use. One of each pair had four electrodes placed on it while they were stored on ice for 24 hours. Afterwards, the cells of the treated kidneys had less damage when viewed under a microscope.
Damage to transplanted kidneys from lack of oxygen is a big problem and contributes to immune rejection, says Kristin Veighey at the University of Southampton in the UK. “If you make [kidneys] last longer, then less people will return to the wait list.”
Source: News Scientist