Another therapeutic approach is use of a trophic factor to replenish or prevent the loss of those dopamine producing cells in the first place.
GDNF has been known to protect and restore these cells in animal models of Parkinson’s Disease since the 1990s.
However, human studies have shown mixed results so far:
Furthermore, subsequent studies have confirmed the clinical benefits of GDNF infusions in Parkinson’s patients, and have even shown a sustained benefit after the infusions were discontinued in one patient.
There are ongoing trials of direct infusions of GDNF into the putamen in the UK using a novel infusion pump:
Another potential approach is to use gene therapy – delivering a virus that carries the DNA to make GDNF directly into the putamen by a single injection. The “infected” neurons will make GDNF on their own to treat the disease.
So, at this point the jury is still out on GDNF and Parkinson’s, watch this space for more information!