Deciphering the role of neuropeptides as biomarkers for early diagnosis of Parkinson's disease.

Parkinson's disease (PD) is a neurological condition and is characterized by both motor and non-motor symptoms. Early diagnosis is essential for effective therapy and management; nevertheless, present diagnostic methods are frequently insufficient and primarily rely on clinical symptoms that appear later in the disease. Neuropeptides, such as alpha-synuclein (α-syn), Substance P (SP), neurotensin (Nts), Neuropeptide Y (NPY), and somatostatin (SST), exhibit significant potential as biomarkers for the early identification of Parkinson's disease (PD). The pathophysiology of Parkinson's disease is closely associated with the dysregulation of these neuropeptides, which are essential in many neurophysiological processes. Advancements in detection technologies, including the Enzyme-Linked Immunosorbent Assay (ELISA), have rendered it possible to precisely and sensitively quantify neuropeptides in a variety of bodily fluids, including blood, saliva, tears, urine, and cerebrospinal fluid (CSF). Studies show that PD patients have different amounts of neuropeptides in their biological fluids. These differences are correlated with the severity of the disease and help to distinguish PD patients apart from individuals with other neurodegenerative conditions. Despite being less investigated, Nts and SST are also involved in neuroprotection and dopaminergic transmission, they too hold significant characteristics as diagnostic biomarkers. This article highlights the possible use of neuropeptides as PD diagnostic biomarkers. Integrating neuropeptide biomarkers into normal diagnostic processes can substantially enhance early diagnosis. This enables early therapeutic interventions and improves outcomes for individuals with PD.