Alzheimer's Disease Overview

Dr. Alois Alzheimer Contributions

• In 1906, Dr. Alois Alzheimer presented a case of a woman named Auguste Deter, marking the first documented case of what would later be named Alzheimer's disease.
• His observations included memory loss, language problems, and behavioral changes, which laid the groundwork for understanding neurodegenerative disorders.

Abnormal Structures in Alzheimer's Disease

• Two key abnormal structures identified in the brains of individuals with Alzheimer's disease are:
  • Amyloid plaques: Aggregates of beta-amyloid peptides that form between neurons, disrupting communication.
  • Neurofibrillary tangles: Twisted fibers composed of hyperphosphorylated tau proteins that accumulate inside neurons, leading to cell dysfunction and death.

Precursor to Amyloid Plaque

• The precursor to amyloid plaque in Alzheimer's disease is the amyloid precursor protein (APP).
• APP is cleaved by enzymes, leading to the production of beta-amyloid fragments, which aggregate to form plaques.

Tau Proteins in Alzheimer's Disease

• In Alzheimer's disease, tau proteins undergo abnormal phosphorylation, resulting in the formation of neurofibrillary tangles.
• This hyperphosphorylation impairs the normal function of tau, which is to stabilize microtubules, thus disrupting neuronal transport and contributing to cell death.

Role of Beta-Amyloid Fragments

• Beta-amyloid fragments accumulate outside neurons, leading to the formation of amyloid plaques.
• These plaques interfere with cell-to-cell communication, trigger inflammatory responses, and promote neurotoxicity, ultimately contributing to cognitive decline in Alzheimer's disease.

Explore the basics of Alzheimer's disease, including its history, symptoms, and impact on the brain. Learn about the pioneering work of Dr. Alois Alzheimer and the characteristic hallmarks of the disease.