Study: Brain Cells Morph Like Stem Cells

Aug. 17, 2006 — Brain cells share qualities such as adaptability and self-renewal with stem cells, suggests a new study.

In fact, a single human brain cell, or neuron, may be able to produce as many cells as exist in the brains of 50 million people. The study is the first to show that ordinary human neurons can lead to such great numbers of replacement cells, as well as morph into different cell types.

"This is a completely new source of human brain cells that can potentially be used to fight Parkinson’s disease, Alzheimer’s disease, stroke and a host of other brain disorders," said Dennis Steindler, lead author of the study, which is published in the current issue of the journal Development.

Steindler, who is the executive director of the University of Florida’s McKnight Brain Institute, added, "We could conceivably grow cells that would come to the rescue of the part of the brain that needed them, but not to build an entire brain or a complete structure. It would probably only take months to get enough material for a human transplant operation."

He explained to Discovery News that he and his team worked with mature human brain cells taken from epilepsy patients undergoing surgical treatment to ease their symptoms. The cells were extracted from tissue in the brain’s gray matter, which is not known for harboring stem cells.

The scientists then gave the cells a "bath" of growing agents, in a step somewhat like adding growth hormone to plant cuttings.

Transplanted into mouse brains, the treated cells seemed to take cues from their environment, producing new neurons that matched the surounding parts of the brain.

The researchers think the chemical bath might have coaxed preexisting neural progenitors, which are stem-like cells, to emerge from the gray matter sample and multiply like rabbits.

The bathing process, they theorize, could allow a single treated brain cell to initiate a cycle of cell division that could repopulate all the cells in 50 million other brains, not to mention that of the donor.

"Potentially this could lead to a new therapy within five years, but these advances have to be made one step at a time," said Steindler, one of the world’s leading stem cell researchers. "I think this discovery helps us figure out the potential of adult brain cells to form new neurons."

Ben Barres, a professor of neurobiology at the Stanford University School of Medicine, agrees with the findings.

"It’s been shown that the same sorts of tissue from the mouse brain can give rise to rapidly dividing cells, but this shows it is true with human cells," Barres said. "That these cells were able to integrate into tissue in an animal model and actually survive — it was extremely important."

Barres added, "Now the question is what will these cells do in a human brain?"