Cinnamon is a popular spice that is derived from the inner bark of trees belonging to the Cinnamomum class. It has a warm, sweet flavor and aroma, making it a commonly used ingredient in both sweet and savory dishes around the world.
There are two distinct types of cinnamon – Ceylon and Cassia. Cassia cinnamon is the most commonly available type of cinnamon and is typically found in supermarkets. It has a stronger, spicier flavour that Ceylon which is considered more delicate and sweet. However, cinnamons potential value may go far beyond its taste. Cinnamon has historically been used in traditional medical practices. Medieval physicians utilized this flavorful spice to treat a variety of disorders like arthritis, common colds and cough.
Cinnamaldehyde is the organic compound that gives cinnamon its distinctive aroma and flavour. This compound is metabolized by the liver into another molecular called sodium benzoate which has the ability to cross the blood-brain-barrier and exert its antioxidant effects in the brain. This has been hypothesized to have a protective role against inflammatory, neurodegenerative diseases like Parkinson’s Disease by reducing toxic, oxidative stress.
Parkinson’s Disease (PD) is a chronic and progressive neurological disorder that primarily affects movement. Common symptoms include progressive tremor, stiffness of the limbs, slowed movements and difficulty with balance and walking. It is characterized by the gradual degeneration of neurons, especially in a part of the brain called the substantia nigra, which leads to a decrease in production of a neurotransmitter called dopamine. Dopamine plays a key role in controlling movement and coordination. As dopamine levels decline, the symptoms of Parkinson’s become more pronounced.
The idea that dietary changes might influence the development of neurodegenerative disorders was first investigated in the 1990s. An article published in JAMA Neurology in 1997 by Dr. de Rijk sought to investigate whether high dietary intake of antioxidants, like cinnamon and other plant-based supplements, could decrease the risk of PD. The community-based study involved over 5000 participants living in the Netherlands. Participants were individuals screened for symptoms of PD and were simultaneously asked to report on the frequency of which they ate certain foods.
Individuals who had a higher intake of dietary antioxidants had a reduced risk of subsequently having Parkinson’s Disease, suggesting a potential protective mechanism.
While this study suggests a correlation between PD and antioxidants, a more recent study published in 2014 in the Journal of Neuroimmune Pharmacology investigated whether cinnamon could have similar effects. The team of scientists led by Dr. Pahan at Chicago’s Rush University Medical Center looked at a mouse model of PD to get a better sense of the disease at a cellular level. They found that mice with PD had a loss of two key proteins, Parkin and DJ-1, which are known to stimulate and support the survival of brain cells that produce dopamine – the neurotransmitter lost in PD.
However, when the animals were given sodium benzoate, the metabolite derived from cinnamon powder that crosses the blood-brain-barrier, it stopped the loss of Parkin and DJ-1 proteins in the brain. This research highlights the cellular and biomechanical changes that occur in the progression of PD – some of which might be reversed with dietary supplements like cinnamon. While this data may still be a way off from having impacts on human patients with PD, it may help scientists understand how the disease works to inform the development of therapies that slow, or stop, the progression of PD.
