These plaques primarily consist of the A isoform, and it interferes with neighbouring synapses to induce tau aggregation in neurons by unknown mechanisms, which causes neuronal damage. A is cleaved from an amyloid precursor protein and is released into the extracellular milieu by a process that is unclear as diffusible oligomers. Ao can be cleared by purchase TBHQ mechanisms that involve APOE or can be taken up by astrocytes via low density lipoprotein receptorrelated protein. Ao can also aggregate in the intercellular space to form fibril lary constructs, which in turn assemble into plaques. A plaques can be cleared from the brain via degradation by endocytic or phagocytic clearance, or by endoproteases from astrocytes; step. However, some conformational oligomers that dissociate from A fibrils and plaques may not be cleared and are toxic to adjacent synapses and induce tau aggregat ion by as yet unknown mechanisms.Tau damage occurs in neurons and is mediated by the development of taupositive neurofibrillary tangles. Fibrillar tau can be released and taken up by healthy neur ons, triggering tau damage in the up taking cell. In addition, A oligomers might drive synuclein aggregation in the plaques.Furthermore, human autopsy examinations have observed neuro fibrillary tangles formation without A plaques, suggesting these two proteins may arise independently in AD or alternatively tangles may occur prior to amyloid plaques, fuelling NFT as the main cause of AD and giving rise to the tau hypothesis.Microtubuleassociated protein bind to the tubulin part of microtubules and regulate their organisation and turnover.Six isoforms of the tau gene on chromosome are found in the human brain, generated by alternative splicing of the premRNA. Normal brain tau contains moles of phosphate per mole of the protein for optimal functionality; however, in AD, tau is fold more phosphorylated. Although the exact process is unknown, these hyperphosphorylated tau proteins accumulate as straight filaments or unique twisted fibrils to form an insoluble structure in neuronal bodies and are referred to as NFT. Brain tau pathology is measured using BRAAK staging, where BRAAK stages I II represent early appearance in the entorhinal region, BRAAK stages IIIIV refers to the compromise of the limbic region, and BRAAK stages VVI are assigned when the neocortical areas are affected. Brain mitochondrial dysfunction has been reported in AD on numerous occasions and combined with the strong maternal genetic contribution in AD, give rise to the mitochondrial cascade hypothesis. The theory buy TBHQ suggests that mitochondrial dysfunction contributes to elevated ROS by generating A, resulting in neuronal progenitors unsuccessfully entering cellcycle and causing phosphorylation of tau and NFT formation.Several studies have also suggested that genetic mutations observed in AD increases an individuals susceptibility to infections and viruses, leading to the viral hypothesis.The concept suggests viruses travel to the brain by middle age due to the agerelated weakening of the immune system, where it remains in a latent form until the virus reactivates by an unknown trigger.In addition, A is an innate immune protein that protects against viral infections and has been shown to bind glycoproteins of the HSV, accelerating A deposition and resulting in protective entrapment of the virus.