A Dead End or Room for Improvement on Parkinson's Medication
Written by Samantha Strom
Edited by Aryss Hearne
May 2, 2021
Edited by Aryss Hearne
May 2, 2021
Research has estimated that by 2030, there will be more than one million people with Parkinson’s disease in the US alone (Marras et al., 2018). As the country’s elderly slowly outnumber the young, the increase in age-related diseases like Parkinson’s will pose a significant problem for healthcare, and it may be difficult to give patients adequate care (Marras et al., 2018; Smetanin et al., 2009). Levodopa (LD or L-Dopa) was first used in 1967 and still remains the best short-term Parkinson’s medication (Hornykiewicz, 2010; Poewe et al., 2010). However, L-Dopa can have debilitating side effects that are similar to symptoms of the disease itself like involuntary jerking and shaking. New research from Uppsala University might help shed light on this phenomenon. Researchers compared two groups of primates treated with L-dopa for Parkinson’s: those with side effects and those without. Those with side effects had an abundance of L-Dopa and a byproduct, 3-O-methyldopa, in all regions except the area researchers originally suspected (the striatum) (Fridjonsdottir et al., 2021; Uppsala University, 2021).
To understand this discovery’s significance and why L-Dopa is even used as a medication, it would help to know how Parkinson’s causes motor problems. In order to move, your brain needs to translate your urge into a coordinated pattern of muscle contractions. You initiate movement in the frontal cortex by the top of the head. This region then transmits info to deeper areas of the brain, including the striatum, that are collectively called the basal ganglia. Other areas like the substantia nigra (SNr) add input before the signals bounce back around and eventually out to your body. The major chemical that the SNr sends out to communicate is dopamine (Cutsuridis, 2013; Parent & Hazrati, 1993). In Parkinson’s disease, the cells living in the SNr die and you lose the dopamine. The communication is disrupted, messages are muddled, and movement is impaired (Dickson et al., 2009; Kalia & Lang, 2015). L-dopa is given as a medication because it helps replace the dopamine that is lost in Parkinson’s and it reduces the motor problems (Poewe et al., 2015).
The side effects of L-dopa seem odd considering that it is supposed to help motor problems. This new discovery of L-Dopa accumulation in different regions of the brain might open up a new direction for the medication. By understanding where and how the medication is going awry, researchers can begin to search for ways to fix it. They could, for example, find medications that target the brain regions behind these unwanted side effects. By minimizing side effects, L-dopa could become even more useful and helpful for Parkinson’s patients. Any medicinal or technological advances that could improve treatment for Parkinson’s patients are important. Age-related disease could affect any of us or our loved ones as we get older after all.
References
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Uppsala University. (2021, January 7). Faulty metabolism of Parkinson's medication in the brain linked to severe side effects. ScienceDaily. Retrieved January 23, 2021 from www.sciencedaily.com/releases/2021/01/210107112140.htm