The FDA defines a biomarker as a specific characteristic that is measured (such as a chemical in the blood) which can be used to indicate how "normally" biological processes are functioning, the severity of pathogenic processes, and most importantly how the body is responding (improving or worsening) to a disease, including how a patient is responding to a given treatment.
A biomarker is not an assessment of how an individual feels, but rather an assessment of the course and direction of the disease process, independent of the patient’s signs and symptoms.
Thus biomarkers serve as a window to objectively observe the underlying disease process in a patient. Most importantly they provide evidence if a specific treatment is merely improving symptoms or physiologically changing and therapeutically modifying the actual course of the disease.
Cystatin C, S100B Protein and Neurofilament Light-chain are blood borne chemicals, easily accessible through routine blood testing that are promising Parkinson’s Disease biomarkers.
A number of published studies suggest these biomarkers can be useful in predicting disease progression, the degree of neuroinflammation, and the risk of cognitive decline in people diagnosed with PD.
Sadly, there are no currently available disease modifying medications in use for the treatment of PD. Without any disease modifying treatments to offer their PD patients, it is not surprising that Movement Disorder Specialists have shown little interest in PD biomarkers.
We as patients have an opportunity to by-pass the MDS and directly demonstrate if our alternative treatments (B1, Cinnamon, Broccoli, etc.) can modify the underlying PD process.
It may be as simple as having a blood test, starting an alternative treatment, then having a follow-up blood test after several months.
I'll report my lab results when I get them.
Cystatin widely available: (Test Code 121251: Cystatin C | Labcorp, n.d.)
NFL available at select locations: (Test Code 140455: Neurofilament Light Chain, Serum | Labcorp)
S100B very limited availability: (Test Code 6905139: S-100B PROTEIN, SERUM | LABCORP OKLAHOMA, INC. | Test Directory, n.d.)
UPDATE: I found a lab that does the S100-b protein blood test (need to figure out the logistics)
2001766 / S-100B Protein, Serum
Out of pocket price is $41.62 subject to change.
aruplab.com
>>>>>>>>>>>>
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Angelopoulou, E., Paudel, Y. N., & Piperi, C. (2021). Emerging role of S100B protein implication in Parkinson’s disease pathogenesis. Cellular and Molecular Life Sciences: CMLS, 78(4), 1445–1453. doi.org/10.1007/s00018-020-...
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