When Warren meets Carlsson!
Posted by: Mariam Rizkallah in Bacteriology, Microbiology storiesRecently, I have been working on an essay for my last year in college. I titled it: “Parkinsonism: Disease and Treatment”, scary enough? NO!!?? I turned it in, anyway. In it, I identified the neurodegenerative disease that targets the basal ganglia and deprives it of the inhibitory neurotransmitter (NT), dopamine. No dopamine means no balance between the excitatory action of the NT, Acetylcholine, and the inhibitory action of dopamine, leading to the well-known clinical picture of parkinsonism that Jankovic (2007) gave the acronym TRAP: Tremor at rest, Rigidity, Akinesia/bradykinesia and Postural instability.
Parkinsonism can be classified into:
- Primary/idiopathic “of unknown cause” which is mostly due to degeneration of dopaminergic neurons (a.k.a Parkinson’s disease)
- Secondary to viral infection as encephalitis & meningitis; drug-induced, e.g., antipsychotics; or due to brain damage caused by trauma, anesthetics, or toxins as MPTP (a contaminant of street-drugs).
You may know that the Nobel Prize associated with Parkinson’s disease didn’t go to Dr. James Parkinson who described it in an essay he wrote back in 1817 calling it “The Shaking Palsy”. It went jointly to Arvid Carlsson, Paul Greengard, and Eric R. Kandel in 2000 (To find out more about the story, here’s the Nobel lecture by Dr. Carlsson). Carlsson and colleagues discovered dopamine as a potential NT in 1957. After that, in 1960, Hornykiewicz and his postdoctoral fellow, then, Ehringer observed the decrease of dopamine levels in Parkinson’s disease patients, and levodopa successful trials started after that, in 1961.
What does Dr. Warren, the scientist whose discoveries led to a paradigm shift in physiology, who said out loud that peptic ulcer is an infectious disease caused by Helicobacter pylori, the gut bacteria? What does he have to do with parkinsonism? Note that: J. Robin Warren and Barry J. Marshall also won Nobel prize in medicine for 2005 for their discovery.
Helicobacter-induced parkinsonism!!
What I am trying to say here—and didn’t say in my essay—is that there is a hypothesis, Helicobacter-hypothesis, that strongly provides another cause of idiopathic parkinsonism, which will not be idiopathic any more, and this cause is H. pylori (Altschuler, 1996). Or to be more accurate, I will say parkinsonism associated with H. pylori. Dobbs and colleagues have carried out well-controlled studies and observed a significant conversion in patients with Parkinson’s disease from malignant into benign parkinsonism after successful eradication of their H. pylori, even with no levodopa administration. The rationale behind this theory is that: H. pylori induces an autoimmune reaction against mitochondria, then a systemic inflammatory response with the whole gang of inflammatory mediators and antibodies reaching and crossing the deficient areas or areas with increased permeability of the blood-brain barrier, causing parkinsonism. And the blood profile can prove the Helicobacter-hypothesis.
Tags: Arvid Carlsson, blood profile, essay, Helicobacter pylori, Helicobacter-hypothesis, idiopathic, J. Robin Warren, James Parkinson, levodopa, Nobel Prize, Parkinson's disease, parkinsonism, shaking palsy, systemic inflammatory response, TRAP