WHAT ARE MICROGLIA CELLS?
Microglia are a type of neuroglia (glial) cell located throughout the brain and spinal cord. Microglia account for 10–15% of all cells found within the brain. An adult brain contains about 100 billion nerve cells, or neurons, with branches that connect at more than 100 trillion points. Scientists call this dense, branching network a "neuron forest."
Microglia are the resident “debris cleaning” cells. They act as the first and main form of active immune defense in the central nervous system (CNS). Microglia (and other neuroglia including astrocytes) are distributed in large non-overlapping regions throughout the CNS. Microglia are constantly scavenging the CNS for cellular debris, pathogens and Aβ plaques, damaged or unnecessary neurons and synapses, and infectious agents. Microglia must be efficient and healthy to prevent potentially fatal damage. Microglia are extremely sensitive to even slight changes in diet, medications, energy levels and pathological changes in the CNS.
WHAT IS AMYLOID BETA PROTEIN?
Amyloid beta (Aβ or Abeta) proteins, (peptides of 36–43 amino acids), and amyloid plaques are involved in the progression of Alzheimer's disease. Aβ molecules can aggregate to form flexible soluble oligomers, like polymers or plastic, which may exist in several forms. It is now believed that certain misfolded oligomers (known as "seeds") can induce other Aβ molecules to also take the misfolded oligomeric form, leading to a chain reaction akin to a prion (“mad cow”) infection. The seeds or the resulting amyloid plaques are toxic to nerve cells. These plaques will accumulate on the neuron cell membrane and along the axion, slowly killing the neuron cell. The other protein implicated in Alzheimer's disease, tau protein, also forms such prion-like misfolded oligomers, and there is some evidence that misfolded Aβ can induce tau to misfold.