1Dr Ibrahim Khan, 2Ansa Batool, 3Dr Abdul Jabbar, 4Dr Jahangir Liaquat, 5Dr.Darya
khan laghari, 6Dr Allah Rakha
Biomarkers in Neurodegenerative Diseases:
Early Detection of Alzheimer’s and Parkinson’s
Disease
Abstract:
Neurodegenerative diseases are progressive disorders characterized by the
accumulation of pathological proteins, neuronal dysfunction, synaptic loss, and progressive
neuronal degeneration. Alzheimer’s disease (AD) and Parkinson’s disease (PD) are among the
most common neurodegenerative disorders and are associated with substantial cognitive, motor, functional, and socioeconomic consequences. Biomarkers have increasingly become important
for detecting pathological changes before advanced clinical manifestations develop.The study
was designed to evaluate the role of established and emerging biomarkers in the early detection
of Alzheimer’s and Parkinson’s disease, with emphasis on blood, cerebrospinal fluid, imaging, and molecular biomarkers.A comparative clinical and biomarker-focused framework was used to
assess biomarkers associated with AD and PD. Biomarkers were evaluated according to their
biological targets, specimen requirements, diagnostic applications, relationship with disease
GlobalHealth & Medicine. 2026; 8(3):291-305. Original Article
DOI:10.35772/ghm.2026.01069
pathology, and potential usefulness during early disease stages. Established and emerging
evidence regarding amyloid, tau, neurofilament, and α-synuclein biomarkers was
considered.Alzheimer’s disease biomarkers demonstrated strong potential for detecting amyloid
and tau pathology, particularly phosphorylated tau species and amyloid-β-based measures. Plasma p-tau217 and related blood-based biomarkers provided promising approaches for lessinvasive detection of AD pathology. In Parkinson’s disease, α-synuclein seed amplification
assays demonstrated strong potential for detecting pathological α-synuclein, while neurofilament
light chain showed usefulness for identifying neuronal injury and distinguishing PD from some
atypical parkinsonian disorders.Biomarkers provided an increasingly important foundation for
biological diagnosis and early detection of neurodegenerative diseases. Blood-based biomarkers
offered practical advantages for AD, whereas α-synuclein-based molecular assays represented an
important advance for PD. Integration of biomarkers with clinical assessment and imaging was
expected to improve diagnostic accuracy and facilitate earlier disease-specific intervention.
Key words
Neurodegenerative diseases; Alzheimer’s disease; Parkinson’s disease; biomarkers;
phosphorylated tau; amyloid-β; α-synuclein; neurofilament light chain; early
full text