Title : Biomarkers in alzheimer´s disease – New perspectives
Abstract:
The development of an early and assertive diagnosis of Alzheimer’s Dementia can contribute to a better quality of life for patients, mainly by providing targeted therapy with measurable results. Biomarkers can be detected in blood levels and, more recently, the feasibility of their identification in salivary samples has been verified. The big challenge lies in the levels of detection and the probable relationship between concentrations in different biofluids. Blood and saliva samples have been evaluated in search of biomarkers, such as TAU and Amyloid Beta, both closely related to the pathophysiology of Alzheimer's Disease. Due to hyperphosphorylation, the normal function of the TAU protein is compromised in terms of stabilization of microtubules in neural networks, leading to the destabilization of microtubules, interfering with axoplasmic flow, and resulting in loss of neuronal connectivity. Hyperphosphorylated tau, in addition to neurofibrillary tangles, is also found in other locations, such as around amyloid plaques. There are hypotheses that associate the protein called neurofilament light chain (NfL) with Alzheimer's disease. NfL stands out as a reliable biomarker in conditions related to neurodegenerative diseases. The NfL is part of a complex called neurofilament (Nf), where associates with other filament subunits intermediates, such as the heavy chain of neurofilament (Nf-H), medium chain (Nf-M) and alphainternexin. In an individual without neurodegenerative disease, that is, under normal conditions, small amounts of Nf-L are released during different stages of the development, maturation and aging cerebral. But it is known that axonal damage or degeneration neuronal release significantly higher Nf-L in the cerebral interstitial fluid, in the cerebrospinal fluid (CSF) and even in the blood. Recently, some tests for screening Alzheimer's disease in blood fluid have been presented, however they cannot yet be considered definitive methods. The biomarkers to be used are the Beta amyloid protein in fractions 40 and 42 amino acids and the TAU protein (pTAU, tTAU), in the TAU181 and TAU 217 subtypes. In this case, the TAU protein has received greater projection and confidence regarding its participation in the pathophysiology of Alzheimer's disease. Doctors have been discouraged from using CSF fluids due to issues related to pain, cost, and risk of infections. A diagnostic solution based on salivary detection can be considered exceptional, especially for screening in small and medium-sized economic countries, places where Alzheimer's disease has grown the most.
Audience Take Away Notes:
- Proposal for new diagnostic strategies
- improve diagnostic assertiveness.
- This investigation can act as an impetus for new discoveries about the pathophysiological process.
- Our studies are not yet completed, but they strengthen the hypotheses.
- We provide new information.
