Role of Platelets in Neurodegenerative Diseases: A Universal Pathophysiology.
ABSTRACT Abstract Platelets play an important role in a variety of disorders viz; cardiovascular, psychosomatic, psychiatric, thrombosis, HIV/AIDS in addition to various neurodegenerative diseases (NDD). Recent evidence indicates that platelet react to diverse stressors thereby offering an interesting vantage point for understanding their potential role in contemporary medical research. This review addresses the possible role of platelets as a systemic probe in various NDD's such as Amyotrophic Lateral Sclerosis (ALS), Parkinson's Disease (PD), Huntington's Disease (HD), Alzheimer's Disease (AD), Multiple Sclerosis (MS) etc. The current review based on published literature, describes a probable link between platelets and pathophysiology of various NDD's. It also discusses how platelets epitomize ultra structural, morphological, biochemical and molecular changes, highlighting their emerging role as systemic tools in different NDD's.
SourceAvailable from: Eugene D Ponomarev[Show abstract] [Hide abstract]
ABSTRACT: Glatiramer acetate (GA, Copaxone, Copolymer-1) is an FDA approved drug for the treatment of MS and it is very effective in suppressing neuroinflammation in experimental autoimmune encephalitis (EAE), an animal model of MS. Although this drug was designed to inhibit pathogenic T cells, the exact mechanism of EAE/MS suppression by GA is still not well understood. Previously we presented evidence that platelets become activated and promote neuroinflammation in EAE, suggesting a possible pathogenic role of platelets in MS and EAE. We hypothesized that GA could inhibit neuroinflammation by affecting not only immune cells but also platelets. We investigated the effect of GA on the activation of human platelets in vitro: calcium influx, platelet aggregation and expression of activation markers. Our results in human platelets were confirmed by in-vitro and in-vivo studies of modulation of functions of platelets in mouse model. We found that GA inhibited thrombin-induced calcium influx in human and mouse platelets. GA also decreased thrombin-induced CD31, CD62P, CD63, and active form of αIIbβ3 integrin surface expression and formation of platelet aggregates for both mouse and human platelets, and prolonged the bleeding time in mice by 2.7-fold. In addition, we found that GA decreased the extent of macrophage activation induced by co-culture of macrophages with platelets. GA inhibited the activation of platelets, which suggests a new mechanism of GA action in suppression of EAE/MS by targeting platelets and possibly preventing their interaction with immune cells such as macrophages. Furthermore, the reduction in platelet activation by GA may have additional cardiovascular benefits to prevent thrombosis.PLoS ONE 05/2014; 9(5):e96256. DOI:10.1371/journal.pone.0096256 · 3.53 Impact Factor
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ABSTRACT: Peripheral biomarkers play an indispensable role in quick and reliable diagnoses of any kind of disease. With the population ageing, the number of people suffering from age-related diseases is expected to rise dramatically over the coming decades. In particular, all types of cognitive deficits, such as Alzheimer's disease (AD), will increase. AD is characterised mainly by coexistence of amyloid plaques and neurofibrillary tangles in brain. Reliable identification of such molecular characteristics ante mortem, however, is problematic due to restricted availability of appropriate sample material and definitive diagnosis is only possible post-mortem. Currently, the best molecular biomarkers available for ante mortem diagnosis originate from cerebrospinal fluid. Though, this is not convenient for routine diagnosis because of the required invasive lumbar puncture. As a consequence, there is a growing demand for additional peripheral biomarkers in a more readily accessible sample material. Blood platelets, due to shared biochemical properties with neurons, can constitute an attractive alternative as discussed here. This review summarises potential platelet AD biomarkers, their role, implication, and alteration in the disease. For easy comparison of their performance, the Hedge effect size was calculated whenever data were available.06/2014; 2(1):65. DOI:10.1186/2051-5960-2-65
Frontiers in Neurology 07/2014; 5:119. DOI:10.3389/fneur.2014.00119