Alzheimer’s Disease Research

Dementia is a disorder that leads to cognitive decline, including memory loss, aphasia, apraxia, and executive dysfunction. There are several types of dementia, including Alzheimer's disease, Lewy body dementia, and vascular dementia, while Alzheimer's disease is known to be the most common form. Alzheimer's disease, which was first reported by Alois Alzheimer in 1906, is characterized pathologically by senile plaques (insoluble deposit formed by aggregation and accumulation of amyloid-β) and neurofibrillary tangles in postmortem brains.

Although the molecular mechanism of the onset of Alzheimer's disease has not yet been elucidated, there is a widely-accepted hypothesis in which Amyloid-β (Aβ) gradually accumulates in the brain over several decades before the onset of the disease, abnormally phosphorylated tau protein subsequently causes neurofibrillary tangles, and finally neuronopathy occurs and causes symptoms.
Aβ has long been studied as a causal factor in Alzheimer's disease. Human Aβ includes Aβ 40 and Aβ 42. Aβ 40 is said to be less cohesive, while Aβ 42 is considered to be more cohesive and more toxic. In previous research, a hypothesis was proposed in which Aβ shows higher toxicity when aggregated into aggregates that are dimers called Aβ oligomers or more complex aggregates. Various molecular species of Aβ oligomers exist, such as dimers, trimers, and 12-mers, and the size of Aβ oligomers that is important is a theme of discussion. Fujifilm Wako offers Aβ Oligomer ELISA Kits that can selectively measure 9-mer or higher Aβ oligomers.

Tau proteins control microtubule stability, as microtubule-associated proteins. Neurofibrillary tangles composed of accumulated phosphorylated tau are formed in the brain of patients with Alzheimer's disease and are reported to correlate with the severity of dementia. In addition, it has been reported that the concentrations of total tau and phosphorylated tau in the cerebrospinal fluid are higher in patients with Alzheimer's disease than in patients without dementia. Although biomarkers for diagnosis of Alzheimer's disease have not yet been established, T181, tau protein phosphorylated at threonine 181, is widely used. Fujifilm Wako provides ELISA kits that can measure total tau protein and phosphorylated tau protein (T181).