New Key to Tissue Regeneration (IMAGE) Tufts University Caption Tufts biologists have regenerated spinal cord and muscle by using a "pharmaceutical cocktail" to trigger an influx of sodium ions into injured cells. The treatment method is most directly applicable to spinal cord repair and limb loss, which are significant problems worldwide, but the proof-of-principle may apply to many complex organs and tissues. The Tufts team found that a localized increase in sodium ions was necessary for young tadpoles to regenerate their tails -- complex appendages containing spinal cord, muscle and other tissue. Like human beings, who regenerate fingertips only as children, tadpoles lose the ability to regenerate their tail with age. The Tufts biologists showed that such "refractory" tadpoles whose tails had been removed could be induced to make a perfect new tail by only an hour of treatment. The tadpole on the left, which received the "cocktail" to trigger an influx of sodium ions, grew a perfectly formed tail. The control tadpole on the right did not regenerate. This approach breaks new ground in biomedicine because it requires no gene therapy; can be effectively administered for some time after an injury has occurred; and is bioelectric, rather than chemically based. Credit Ai-Sun Tseng and Michael Levin-Tufts University Usage Restrictions Use only with appropriate credit and caption License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.