Alzheimer’s disease is the most common form of dementia that involves impaired cognitive and behavioural functions.
The most characteristic symptoms of Alzheimer’s are: memory deficits, personality changes, language problems, confusion, disorientation and loss of reasoning and judgement skills. Alzheimer’s disease also depends on genetic and environmental factors: lifestyle and familiarity influence the course of the disease.
13% of people with juvenile Alzheimer’s disease have a family history of the disease, and it is thought that the condition results from a hereditary genetic mutation.
Early diagnosis of the disease allows you to intervene more quickly, prevent rapid deterioration and choose the most appropriate patient management. It has been seen that in patients with Alzheimer’s, the brain undergoes a process of atrophy and presents protein aggregates that seem to negatively affect the survival and function of neurons.
These are both protein aggregates (plaques) of beta-amyloid peptides that form on the outside (extracellular) and inside (intracellular) of neurons. Within neurons, the presence of neurofibrillary clusters of hyperphosphorylated tau protein was also found to reflect the intensity of neuronal and axonal damage.
The role of protein aggregates is not yet completely clear, but scientific evidence confirms that beta-amyloid plaques and tau protein clusters interfere with normal interneuronal (between neurons) nerve transmission and are capable of causing nerve cell death.
The presence of neurofilaments (intracellular intermediate filaments) in the blood and cerebrospinal fluid also represents a non-invasive biomarker of neurodegeneration, in particular of axial damage.
The concentration of the protein S100B (astroglial calcium-binding protein) in the cerebrospinal fluid reflects the severity of the pathological condition. In many cases, however, the levels of S100B in the blood remain unchanged during the course of the disease. Neuron-specific enolase NSE (a glycolytic isoenzyme located in central and peripheral neurons and neuroendocrine cells) is a biomarker of neuronal stress and has prognostic potential for several neurological disorders as well as Alzheimer’s.
One of the crucial factors in the regulation of the innate immune system during the progression of AD is the TREM2 receptor expressed on myeloid cells 2. It is a transmembrane protein specifically expressed by the microglia of the brain, and its concentration is known to increase 5 years before the onset of symptoms in AD.
