An elderly patient presents with accumulating amyloid plaques in the brain. Which mechanism explains why age-related decline reduces amyloid clearance via the glymphatic system?

💡 Explanation

Impaired astrocyte end-feet polarization disrupts perivascular space organization, hindering cerebrospinal fluid influx. The glymphatic system clears amyloid via convective flow. Because polarization is reduced, clearance is impaired, therefore amyloid accumulates, rather than being efficiently removed by a functional glymphatic system.

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