Advances on Therapeutic Strategies for Alzheimer's Disease: From Medicinal Plant to Nanotechnology.

Alzheimer's disease (AD) is a chronic dysfunction of neurons in the brain leading to dementia. It is characterized by gradual mental failure, abnormal cognitive functioning, personality changes, diminished verbal fluency, and speech impairment. It is caused by neuronal injury in the cerebral cortex and hippocampal area of the brain.