Comprehensive Profiling of Blood Coagulation and Fibrinolysis Marker Reveals Elevated Plasmin-Antiplasmin Complexes in Parkinson's Disease

Parkinson's disease (PD) is the second most common age-related neurodegenerative disease. Accumulating evidence demonstrates that alpha-synuclein (alpha-Syn), an apparently predominant neuronal protein, is a major contributor to PD pathology. As alpha-Syn is also highly abundant in blood, particularly in red blood cells (RBCs) and platelets, this in turn raises the question on the function of presumably dysfunctional alpha-Syn in peripheral cells and its putative effect on the other enclosed constituents. Herein, we detected the internal variance in erythrocytes of PD patients by Raman spectroscopy, but no measurable amount of erythrocytic behavioural change (eryptosis) or any haemoglobin variation was noticed. An elevated level of plasmin-antiplasmin complexes (PAP) was observed in the plasma of PD patients, indicating activation of the fibrinolytic system, but platelet activation after thrombin stimulation was not altered. Sex-specific patterns were noticed for blood coagulation factor XIII and factor XII activity in PD patients. Additionally, the alterations in homocysteine levels which have often been observed in PD patients were found to be independent from L-DOPA usage and PAP levels. Furthermore, a selective gene expression analysis identified subsets of genes related to different blood-associated compartments (RBCs, platelets, coagulation-fibrinolysis) also involved in PD-related pathways.

Automated summary

Parkinson's disease (PD) is the second most common age-related neurodegenerative disease, with accumulating evidence suggesting alpha-synuclein's major role in PD pathology. This study found internal variance in erythrocytes of PD patients through Raman spectroscopy, as well elevated levels of plasmin-antiplasmin complexes (PAP) in their plasma. Platelet activation after thrombin stimulation was not altered in PD patients. Sex-specific patterns and alterations in homocysteine levels were also observed.