We reached out to Joon Faii Ong, M.D., to hear about emerging treatments for Parkinson’s disease (PD). Dr. Joon Faii Ong is an expert on Parkinson’s Disease and was kind enough to sit down with us for an interview.
Parkinson’s Disease (PD) is a progressive neurodegenerative disorder that affects 1% of people over 40 and 3-4% of people over 60. Like Alzheimer’s disease (AD), the degeneration process involves the loss of neurons in some regions but only affects the dopaminergic neurons in the substantia nigra pars compacta. Clinically, PD is characterized by slowness of movement (bradykinesia), stiffness of muscles, and tremors. The symptoms are often managed with medications that increase dopamine levels or replace dopamine, but eventually, these treatments become less effective as Parkinson’s worsens.
There are currently no FDA-approved treatments to slow down or stop the dopaminergic neuron loss associated with PD. As a result, there is an urgent need for new therapies to halt disease progression and protect neurons from damage caused by oxidative stress, metabolic dysfunction, mitochondrial defects, neuroinflammation, etc. Various cannabinoids and endocannabinoids have been studied as potential neuroprotective therapies for PD. These molecules, such as THC and CBD, activate cannabinoid receptors in the brain that can protect neurons from damage and reduce PD symptoms without psychoactive effects or addiction.
According to Dr. Ong, cannabinoids’ therapeutic potential to treat Parkinson’s Disease is promising, especially in early-stage disease. However, it is important to recognize that these are still considered experimental therapies, and their effects must be corroborated with larger clinical trials.
Other potential treatments for Parkinson’s Disease include:
- Neurorestorative agents – these promote the regrowth of neurons to replace those that have already been lost. The most well-known example is neural stem cells, but other cell-based therapies are also studied, such as mesenchymal stem cells and olfactory ensheathing cells.
- Neuroprotective agents protect the remaining dopaminergic neurons from further damage but do not promote neuron regrowth or produce new neurons. Two examples are statins and N-acetylcysteine. Statins have been shown to improve motor function in early PD patients, while N-acetylcysteine shows promise to reduce dyskinesia.
- Neurotrophic factors stimulate the development and growth of neurons, helping to restore dopaminergic function lost as PD progresses. The neurotrophic factor glial cell line-derived neurotrophic factor (GDNF) is used to treat advanced PD.
- Monoamine oxidase-B (MAO-B) inhibitors – slow the breakdown and reduce levels of dopamine and other neurotransmitters, similar to how certain types of Parkinson’s Disease medications work today. There are several drugs approved for this now, including selegiline and rasagiline.
- Deep brain stimulation – this uses an electrode to deliver electrical impulses directly to the affected regions of the brain. This is the most well-known and widely used surgical treatment for Parkinson’s Disease, and it can significantly improve motor function in many patients. However, not all people respond well to DBS, and there are still many side effects associated with the surgery.
- Cogane – this is a synthetic molecule that mimics dopamine, stimulating dopaminergic neurons to reduce symptoms of Parkinson’s Disease by improving their signaling ability. Unfortunately, cogane does not cross the blood-brain barrier well, and its effectiveness has been questioned.
- Melatonin – This is a hormone that regulates sleep and wake patterns, and it has been shown to improve symptoms such as hypokinesia in PD patients. It may work by preventing the death of dopaminergic neurons or by protecting them from oxidative damage. Administration of melatonin has been shown to increase life span in animal models of PD.