An overview of biomarkers in Alzheimer’s disease

Alzheimer’s disease (AD), also called presenile dementia, is one of the most common neuro­degenerative diseases in elderly people.  The main pathological features of AD include senile plaques (SPs), neurofibrillary tangles (NFTs) and neuron loss.  A biomarker is a characteristic that can be objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacological responses to a therapeutic intervention.  Class biomarkers of AD such as Aβ and phosphorylated tau have been widely used in clinical diagnosis of AD patients.  Recently, novel technologies like proteomics, genomics, and imaging techniques have expanded the role of a biomarker from early diagnosis to monitoring the progression of diseases and evaluating the response to various treatments.  In this article, we will review the progress of various biomarkers of AD.