You’re not going to cut my eyes open again, are you? (Image: Nature Productions/NaturePL)

See gallery: “Do it again: Round-up of regenerating animals“

They are the phoenix of the ponds. Newts have a remarkable ability to regenerate body parts – in this case the lenses in their eyes – time and time again.

Over a 16-year period, Panagiotis Tsonis at the University of Dayton, Ohio, and colleagues removed the lenses of six Japanese newts (Cynops pyrrhogaster) 18 times. After each excision, the lenses regenerated. They did so not from remaining lens tissue, but from pigment epithelial cells in the upper part of the iris.


By the end of the study the newts were 30 years old, five years older than their average lifespan in the wild. Even so, the regenerated lenses from the last two excisions were indistinguishable from lenses of 14-year-old adults that had never regenerated a lens.

Importantly, the expression of key genes involved in lens formation was identical. These include the genes controlling the formation of crystallin – a vital protein component of the lens – and regulatory genes.

Tsonis says the regenerative abilities may be down to efficient DNA repair. “The knowledge that newts can regenerate even in old age presents an opportunity to uncover mechanisms of regeneration resistant to ageing,” says James Godwin of the Australian Regenerative Medicine Institute in Clayton, Victoria. This, he adds, could one day help develop therapies to extend tissue regeneration in humans.

Journal reference: Nature Communications, DOI: 10.1038/ncomms1389