Dr. Su-Chun Zhang of the Department of Neuroscience and Dr. Marina Emborg of the Wisconsin National Primate Research Center have made a breakthrough in the study of monkeys with Parkinson’s disease.
Parkinson’s disease damages neurons in the brain that produce dopamine, a brain chemical that transmits signals between nerve cells. The disrupted signals make it progressively harder to coordinate muscles and causes rigidity, slowness, and tremors that are the disease’s hallmark symptoms. Other symptoms can include depression and anxiety, which often presents itself in pacing behaviors and disinterest in activities or treats in monkeys.
The researchers discovered that grafting neurons grown from monkeys’ own cells into their brains relieved the debilitating movement and depression symptoms associated with Parkinson’s disease.
“The idea is very simple,” Zhang said. “When you have stem cells, you can generate the right type of target cells in a consistent manner. And when they come from the individual you want to graft them into, the body recognizes and welcomes them as their own.”
Within six months, the monkeys that got grafts of their own cells were making significant improvements. Within a year, their dopamine levels had doubled and tripled. When monkeys were given grafts from donor monkeys’ cells, the symptom relief was not present.
Zhang’s lab has spent years learning how to incorporate donor cells from a patient back into a stem cell state, in which they have the power to grow into nearly any kind of cell in the body, and then redirect that development to create neurons.
The results are promising enough that Zhang hopes to begin work on applications for human patients in the future.
You can read more about this remarkable discovery here: https://news.wisc.edu/individualized-brain-cell-grafts-reverse-parkinsons-symptoms-in-monkeys/
Or the full version of the study here: Tao, Y., Vermilyea, S.C., Zammit, M. et al. Autologous transplant therapy alleviates motor and depressive behaviors in parkinsonian monkeys. Nat Med (2021). https://doi.org/10.1038/s41591-021-01257-1