Harvard University researchers and their colleagues have brought new hope to the regenerative medicine field in the aftermath of drug developer Geron's ($GERN) high-profile move to kill its stem cell programs this month. The researchers showed that neurons transplanted into the brains of mice with a genetic defect that causes them to become obese repaired damaged signaling and helped the rodents lose weight.

Make no mistake: The researchers have no plans to move ahead with a new weight-loss therapy. The goal of the study was to provide early proof that transplanted neurons could fix the circuitry of the brain, paving the way to regenerative treatments for ALS and other diseases of the central nervous system. With this in mind, the success of the experiment was apparent in the loss of weight among mice that got the transplants, in addition to measurements of metabolic activity.

For the experiment, mice that lacked a receptor for the weight-control hormone leptin received neurons transplanted from the embryos of healthy mice. The "immature" neurons, which were transplanted into the hypothalamuses of the obese mice, developed into four different types of neuronal cells and restored the broken circuitry in the brains of the rodents. With their brains able to respond to leptin, the mice dropped some weight.

"What we found is that these neurons not only turned into the right kinds of cells, but that they sent signals to the recipients' brain and received signals from the recipients' brain," said study co-author Jeffrey Macklis of Harvard University, in a statement.

Researchers hope that the findings lead to new ways of treating CNS conditions such as spinal cord injuries, autism and epilepsy as well as Huntington's and Parkinson's diseases, reported Medical News Today.

- here's the release
- read the Medical News Today report
- and one from New Scientist

Related Articles:
Geron abandons pioneering stem cell program, lays off 66
Small ALS stem cell study takes a big step forward
At last, a cause found for Lou Gehrig's disease