Which statement describes the downstream pathology of Alzheimer's disease as per the amyloid cascade?

Which statement describes the downstream pathology of Alzheimer's disease as per the amyloid cascade?

• A. Tau hyperphosphorylation occurs independently of beta-amyloid deposition.
• B. Beta-amyloid deposition initiates a cascade leading to tau hyperphosphorylation, neurofibrillary tangles, neuronal loss, and cognitive decline.
• C. Neuroinflammation alone drives cognitive decline without amyloid involvement.
• D. Tau tangles prevent beta-amyloid deposition.

Answer: (C)

Beta-amyloid deposition initiates a cascade that drives tau hyperphosphorylation, formation of neurofibrillary tangles, neuronal loss, and cognitive decline. When beta-amyloid aggregates accumulate, they trigger abnormal phosphorylation of tau, causing tau to detach from microtubules and form tangles inside neurons. These tangles disrupt intracellular transport and synaptic function, leading to neuron dysfunction and death, which underlies the progressive memory and thinking impairments of Alzheimer's disease. Neuroinflammation tends to accompany this process, but the cascade principle centers on beta-amyloid provoking the tau pathology that ultimately leads to neurodegeneration and cognitive decline. The other statements don’t fit this sequence: tau changes occurring without beta-amyloid, cognitive decline driven by inflammation alone, or tau tangles preventing beta-amyloid deposition contradict the established cascade.

Beta-amyloid deposition initiates a cascade that drives tau hyperphosphorylation, formation of neurofibrillary tangles, neuronal loss, and cognitive decline. When beta-amyloid aggregates accumulate, they trigger abnormal phosphorylation of tau, causing tau to detach from microtubules and form tangles inside neurons. These tangles disrupt intracellular transport and synaptic function, leading to neuron dysfunction and death, which underlies the progressive memory and thinking impairments of Alzheimer's disease. Neuroinflammation tends to accompany this process, but the cascade principle centers on beta-amyloid provoking the tau pathology that ultimately leads to neurodegeneration and cognitive decline. The other statements don’t fit this sequence: tau changes occurring without beta-amyloid, cognitive decline driven by inflammation alone, or tau tangles preventing beta-amyloid deposition contradict the established cascade.