Effect of orthovanadate on platelet aggregation induced by platelet-activating factor

Serum trace elements are associated with hemostasis, lipid spectrum and inflammatory markers in men suffering from acute ischemic stroke

The primary objective of the study is investigation of the association between trace elements status and hemostasis, lipid spectrum and inflammatory markers in acute ischemic stroke (AIS). A total of 30 men suffering from AIS and 30 healthy controls were involved in the current survey. Blood count, serum lipid spectrum, complement components C4 and C3a, vascular endothelial growth factor (VEGF), S100B protein, NR2 antibodies (NR2Ab), and total antioxidant status (TAS), as well as plasma fibrinogen, and D-dimer levels and activated partial thromboplastin time (APTT) were assessed. Serum trace elements were analyzed using inductively coupled plasma mass spectrometry. AIS patients were characterized by significantly increased fibrinogen, D-dimer, TG, C3a, C4, NR2Ab, and VEGF levels. The leukocyte count, erythrocyte sedimentation rate and serum atherogenic index were also increased in stroke patients. Oppositely, TAS and APTT values, bleeding and blood coagulation time were decreased. AIS patients were characterized by significantly decreased serum Fe and Co concentrations, whereas the level of Cu, I, Li, Mn, Se, Zn, As, Pb, Ni, and especially V and B in serum was significantly increased. Serum V and B tightly correlated with the procoagulant state and inflammatory markers. Multiple regression analysis revealed a significant inverse association between serum Se levels and stroke markers after adjustment for covariates. Therefore, it is hypothesized that elements like vanadium and boron may be closely involved in stroke pathogenesis by modulation of hemostasis and inflammation, whereas the observed increase in Se levels may be considered as a compensatory reaction.

Role of oxidative stress on platelet hyperreactivity during aging

Thrombotic events are common causes of morbidity and mortality in the elderly. Age-accelerated vascular injury is commonly considered to result from increased oxidative stress. There is abundant evidence that oxidative stress regulate several components of thrombotic processes, including platelet activation. Thus oxidative stress can trigger platelet hyperreactivity by decreasing nitric oxide bioavailability. Therefore oxidative stress measurement may help in the early identification of asymptomatic subjects at risk of thrombosis. In addition, oxidative stress inhibitors and platelet-derived nitric oxide may represent a novel anti-aggregation/-activation approach. In this article the relative contribution of oxidative stress and platelet activation in aging is explored.

Artificial Neural Network Modeling of Ultrasound-Assisted Polysaccharides Extraction from Potentilla anserina and Anti-Platelet Aggregation Activity

In this study, Ultrasound-assisted extraction (UAE) was used for polysaccharides extraction from Potentilla anserina. A computer-stimulated artificial neural network (ANN) was developed to get a correlation between the input variables and the output parameter. Finally, the optimal process conditions were obtained as follows: extraction temperature 55 °C, extraction time 55 min, ratio of liquid to solid 20:1, power 175 W. Under optimized conditions, ultrasound-assisted extraction had obviously higher yield of polysaccharides than the traditional heat reflux method. The optimization procedure showed a close interaction between the experimental and simulated values for polysaccharides extraction. The R2 (0.99271) and MSE (0.0425) values of model suggested good fitness and generalization of the ANN. Moreover, the results also indicated that polysaccharides have inhibitory effect on ADP-induced platelet aggregation.

The effect of vanadium on platelet function

Vanadium pentoxide (V(2)O(5)) inhalation effect on platelet function in mice was explored, as well as the in vitro effect on human platelets. Mouse blood samples were collected and processed for aggregometry and flow cytometry to assess the presence of P-selectin and monocyte-platelet conjugates. Simultaneously, human platelets were processed for aggregometry(.) The mouse results showed platelet aggregation inhibition in platelet-rich-plasma (PRP) at four-week exposure time, and normality returned at eight weeks of exposure, remaining unchanged after the exposure was discontinued after four weeks. This platelet aggregation inhibition effect was reinforced with the in vitro assay. In addition, P-selectin preserved their values during the exposure, until the exposure was discontinued during four weeks, when this activation marker increased. We conclude that vanadium affects platelet function, but further studies are required to evaluate its effect on other components of the hemostatic system.