Brazilian researchers announced progress toward the use of implanted stem cells as a treatment for Parkinsons disease.

Investigations at the DOR Institute for Research and Education (IDOR) and Federal University of Rio de Janeiro (UFRJ) report that their newly developed therapy reduced symptoms in mice.

Using an FDA approved substance for treating stomach cancer, S.K. Rehen and colleagues were able to grow dopamine-producing neurons derived from embryonic stem cells. The cells remained healthy and functional for as long as 15 months after implantation into mice restoring motor function without forming tumors.

Parkinsons, which affect as many 10 million people in the world, is caused by a depletion of dopamine-producing neurons in the brain.

Current treatments include medications and electrical implants in the brain which causes severe adverse effects over time and fail to prevent disease progression.

In the current study, researchers build upon past investigations that have indicated the transplantation of embryonic stem cells improves motor functions in animal models. However, until now, the procedure has shown to be unsafe, because of the risk of tumors upon transplantation.

To address this issue, the researchers pre-treated undifferentiated mouse embryonic stem cells with mitomycin C a drug already prescribed to treat cancer. The substance blocks the DNA replication and prevents the cells to multiply out of control.

The researchers used mice modeled for Parkinsons. The animals were separated in three groups. The first one, the control group, did not receive the stem cell implant. The second one, received the implant of stem cells which were not treated with mitomycin C and the third one received the mitomycin C treated cells.

After the injection of 50,000 untreated stem cells, the animals of the second group showed improvement in motor functions but all of them died between three and seven weeks later. These animals also developed intracerebral tumors.

In contrast, animals receiving the treated stem cells showed improvement of Parkinsons symptoms and survived until the end of the observation period of 12 weeks post-transplant with no tumors detected. Four of these mice were monitored for as long as 15 months with no signs of pathology.

Excerpt from:
Stem Cell Therapies on Mice Reduce Parkinson Symptoms