Biomarkers: From early detection to treatment personalization.

Neurodegenerative disorders (NDs), such as Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS), present increasing issues associated with the unavoidable aging of the world's population. These challenges are further highlighted by the socioeconomic consequences of these diseases. The identification and use of biomarkers for prompt diagnosis, careful observation, and efficient treatment approaches is essential to overcoming these obstacles. The primary methods for diagnosing neurodegenerative illnesses are invasive procedures like lumbar punctures to measure CSF fluid or functional brain imaging methods. Biomarkers for underlying proteinopathy in blood serum and cerebral fluid have been the focus of recent biological research, particularly in vivo. With their ability to provide novel pathways for early detection, illness progression tracking, and individualized treatment plans, biomarkers have become essential instruments in precision medicine. The classification of biomarkers including fluid, digital imaging, and molecular biomarkers is examined in this chapter, with an emphasis on their function in neurodegenerative diseases. In neurodegenerative illnesses and the aging brain, tau, amyloid-β, α-synuclein, and TDP-43 are commonly seen to be deposited together rather than separately. These may be disregarded, and it might be challenging to determine their clinicopathological significance. An overview of illness pathophysiology, diagnostic implications, and the most recent molecular and ultrastructural categories for neurodegenerative disorders are given in this chapter. Addressing these issues through interdisciplinary research and technological advancements will be crucial for the future of biomarker-driven precision medicine. This chapter provides an in-depth overview of the evolving landscape of biomarkers and their transformative impact on the early detection and personalized treatment of neurodegenerative diseases.