BRNI Research
Diagnostics Development
When it begins, Alzheimer's disease (AD) is often difficult to distinguish from other dementias as well as other causes of mild cognitive impairment (MCI). Potential treatments of AD, however are likely to have their greatest efficacy before the devastating and widespread impairment of brain function that inevitably develops with longstanding AD, i.e. of greater than four years' duration.
BRNI has recently validated a new, internally controlled peripheral biomarker for skin fibroblasts (with potential for blood cells as well) that shows its greatest sensitivity during the first 1-2 years of AD onset. The inflammatory signal, bradykinin, which occurs naturally in brain, skin, and blood cells, stimulates a change in the enzyme target called MAP kinase Erk1/2. The Erk 1/2 response was abnormal for AD vs. age matched controls and vs. non-AD dementias such as Parkinson's disease, multiple infarct dementia and Huntington's Chorea. The BRNI biomarker showed high accuracy for tissue bank samples as well as for samples obtained in a previous study from patients with autopsy-confirmed diagnoses.
With this painless skin test the accuracy of clinical diagnosis was significantly enhanced, particularly for early AD when treatment could be most beneficial. The molecular pathway measured by the BRNI biomarker includes the same enzyme, PKC, that is targeted by the AD drug, bryostatin, to treat both the symptoms and neurodegeneration of AD.
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