Parkinson’s Disease Research — Continued

More ongoing Parkinson’s disease research

• The drug isradipine. This calcium channel blocker has long been used to treat high blood pressure, and studies revealed people who take the drug have a reduced risk for developing Parkinson’s disease. Isradipine, which seems to have a protective effect on brain cells that make dopamine, is being tested to see if it can help treat and halt progression of PD in early cases of the disease. The most recent studies, however, have had disappointing results.
• Medication for diabetes. Drugs called GLP-1 agonists, including the injectable drug exenatide, may cut the risk of developing Parkinson’s.  The research is consistent with other studies evaluating whether exenatide helps Parkinson’s patients.
• Gene therapy. Scientists are studying whether gene therapy with glial derived neurotrophic factor (a protein that may help protect dopamine-producing nerve cells) can improve the health and function of neurons that produce dopamine in advanced cases of Parkinson’s disease. While clinical trials have failed to produce results, research on the underlying mechanism may still do so. 
  
• Drugs that target mitochondrial function. Mitochondria are specialized structures inside cells that are often called cellular energy factories — and they may play an important role in PD. Parkinson’s disease research has found hundreds of genes involved in mitochondrial function are less active in people with Parkinson’s. Scientists are investigating drugs that target genes involved in mitochondrial function to see if the medications can slow progression of the disease.
• Deep brain stimulation (DBS). The National Institute of Neurological Disorders and Stroke helped develop DBS, which involves sending electrical impulses through implanted electrodes to specific targets in the brain, to relieve movement symptoms of Parkinson’s. DBS is a treatment option for some patients whose symptoms no longer respond to Parkinson’s disease medications. Researchers are investigating the optimal sites for implanting electrodes within the brain to help even more people with Parkinson’s regain function. The Parkinson’s Foundation has also discovered that DBS Parkinson’s patients at one center had better outcomes than at others and is studying its protocols.
• Environmental studies. Repeated exposure to certain metals and pesticides, herbicides, and other chemicals may play a role in the development of PD — but proving the case usually isn’t easy. For example, the U.S. Environmental Protection Agency has reapproved paraquat, a commercial herbicide possibly linked to Parkinson’s that has been banned in the European Union.  The industrial solvent trichloroethylene has been linked to PD among people exposed during factory work.
• Researchers at La Jolla Institute for Immunology have uncovered evidence that Parkinson’s may be an autoimmune disorder. Certain proteins may be attracting T-cells, immune system fighters, to mistakenly attack brain cells and potentially contribute to the progression of Parkinson’s. The study was the first direct evidence that autoimmunity could play a role in Parkinson’s disease.
• The drug nilotinib (Tasigna), approved since 2007 to treat leukemia, a blood cancer, inhibits enzymes called tyrosine kinases that stimulate cancer cells to grow. In Parkinson’s disease, researchers thought it might eliminate abnormal buildups of dangerous proteins involved in several incurable and devastating neurological diseases.
• A meta-analysis has showed that different doses of nilotinib are safe and tolerated by patients, and improved a key biomarker. But it didn’t help patients’ movement problems.

It’s still possible that the mechanism that seemed so promising could be successful but probably with a different molecule than nilotinib. Researchers are studying other related molecules.

Continue Article...