By DIANE CHUN
Sun staff writer

Cut the limb off a starfish, and it will regrow a new one.

If a cat pulls the tail off a salamander, within a few weeks it will be skittering across the patio, having grown a replacement.

What's their secret? And why isn't it so easy for humans to regenerate parts of the body after an injury or illness?

The newly launched Regeneration Project at the McKnight Brain Institute of the University of Florida will seek to unlock the secrets of regeneration in species like starfish, newts, salamanders, even flatworms, and apply them to treat all-too-human problems ranging from Alzheimer's and Parkinson's disease to spinal cord injury.

Dennis Steindler, executive director of the McKnight Brain Institute, leads the project, which will connect researchers working with adult human stem cells - the building blocks of self-renewal that exist within our brain, bone marrow and blood - with scientists who study how tissues and limbs develop in a variety of organisms.

"A think tank like this is where you get the big answers to big questions," Steindler said Friday.

The Regeneration Project will be funded by some $6 million in private donations, university support and state matching funds.

Two private gifts, from Jon and Beverly Thompson of Sanibel and the Thomas H. Maren Foundation in Gainesville, will help support young researchers in far-ranging disciplines. What will tie them together is their pursuit of the keys to unlock the mystery of regeneration.

"This is a project without walls that will include the Whitney Marine Lab and other marine biology labs," Steindler said. "It will also go overseas, but there will always be a collaboration with UF researchers here."

Steindler says he foresees surprisingly few barriers to understanding growth in simple systems and then applying those insights to the more complex tissue reconstruction needed in human organisms.

Steindler said the project will involve researchers from far-ranging disciplines, including scientists who study how vertebrate development began millions of years ago as well as scientists who are trying to treat blindness by influencing the activity of stem cells in the human eye. In terms of brain diseases, scientists may look at ways to mobilize and reinforce the body's own supply of adult stem cells to protect against or fight Alzheimer's and Parkinson's diseases, cancer, multiple sclerosis and traumatic injury.

"I believe we will be able to ask questions and get answers that go not just from A to B, but from A to Q, leapfrogging us quickly forward," he said.

Recently, studies have shown humans possess some of the same genes and communication pathways used by some of nature's most remarkably regenerative animals.

Already, MBI scientists have discovered more than 100 genes associated with all major human neurological diseases in a simple marine snail, as well as more than 600 genes that control development.

In the realm of adult human stem cells, Brain Institute researchers have shown ordinary human brain cells can generate new brain tissue in mice and produce large amounts of new brain cells in culture for use as possible replacements for dead or injured cells.

The UF project is "bold" because it takes a comprehensive view of regenerative medicine, according to Arlenes Chiu, director for scientific activities at the California Institute for Regenerative Medicine.

"We are all excited by the great potential of stem cells to repair damage and return function," Chiu said. "It remains a great mystery, however, why some organisms are able to renew tissues, organs and even restore whole limbs while other related animals are not. Even within a single organism, we find that some tissues have a far more robust ability to replenish and replace cells than others. Yet we do not understand the bases for these differences."

All the more reason to attack the mystery with a carefully assembled brain trust of scientists, in Steindler's view. "The time is exactly right for something like this," he said.

Diane Chun can be reached at 352-374-5041 or chund@gvillesun.com