Preeclampsia: Integrated network model of platelet biomarkers interaction as a tool to evaluate the hemostatic/immunological interface

Anti-inflammatory, ulcerogenic and platelet activation evaluation of novel 1,4-diaryl-1,2,3-triazole neolignan-celecoxib hybrids

This study reports the synthesis of novel neolignans-celecoxib hybrids and the evaluation of their biological activity. Analogs8-13(L13-L18) exhibited anti-inflammatory activity, inhibited glycoprotein expression (P-selectin) related to platelet activation, and were considered non- ulcerogenic in the animal model, even with the administration of 10 times higher than the dose used in reference therapy. In silico drug-likeness showed that the analogs are compliant with Lipinski's rule of five. A molecular docking study showed that the hybrids8-13(L13-L18) fitted similarly with celecoxib in the COX-2 active site. According to this data, it is possible to infer that extra hydrophobic interactions and the hydrogen interactions with the triazole core may improve the selectivity towards the COX-2 active site. Furthermore, the molecular docking study with P-selectin showed the binding affinity of the analogs in the active site, performing important interactions with amino acid residues such as Tyr 48. Whereas the P-selectin is a promising target to the design of new anti-inflammatory drugs with antithrombotic properties, a distinct butterfly-like structure of 1,4-diaryl-1,2,3-triazole neolignan-celecoxib hybrids synthesized in this work may be a safer alternative to the traditional COX-2 inhibitors.

Thrombin Generation and other hemostatic parameters in patients with atrial fibrillation in use of warfarin or rivaroxaban

Patients with atrial fibrillation (AF) present hyperactivation of both platelets and coagulation leading to a hypercoagulable state which contributes to an increased risk of thromboembolism. Therefore, one of the main strategies for treatment of AF is prevention of these events through the use of oral anticoagulants (OAC). The aim of this study was to evaluate hemostasis as a whole in patients with non-valvular AF undergoing warfarin or rivaroxaban by thrombin generation test (TGT), in addition to monocyte-platelet aggregates (MPA), glycoprotein IIb/IIIa (GPIIb/IIIa), and platelet (PMP) and endothelium (EMP) microparticles, compared to age and sex matched controls. PT/INR for OAC use was also determined. In patients taking OAC, compared to control group, a decrease in TGT (p = 0.000 for all parameters) were observed. Patients taking warfarin showed to be more hypocoagulable, presenting lower levels of ETP (p = 0.000) and peak (p = 0.002) than patients using rivaroxaban. Patients on warfarin use with INR > 3 had also lower levels of ETP (p = 0.01) and peak (p = 0.006). A decrease in ETP (p = 0.03) and peak (p = 0.02) values was also observed in patients using rivaroxaban with PT > 21.4 s. Patients using warfarin (p = 0.000) and rivaroxaban (p = 0.000) presented lower levels of MPA in relation to control group. It was also observed in patients using warfarin, lower GPIIb/IIIa levels in relation to control group (p = 0.011). Patients taking rivaroxaban (p = 0.003) and warfarin (p = 0.001) had higher PMP levels compared to control group. There was no difference in levels of EMP between the groups (p = 0.0536). The present study reinforces the usefulness of OAC in AF, which decisively contribute to a better management of the disease preventing possible complications.

L-NAME-induced Preeclampsia: correction of functional disorders of the hemostasis system with Resveratrol and Nicorandil

Introduction. Preeclampsia is a formidable disease of the second half of pregnancy, leading to severe complications, including disability and even death. Many authors have recognized the correlation between the severity of preeclampsia and the degree of disturbances in the hemostasis system. In this regard, the objective of this study was to assess inhibition of platelet aggregation and the possibility of its correction with resverаtrol and nicorandil.

Materials and methods. The study was performed on 250 mature white Wistar female rats weighing 250–300 g. The platelet aggregation induced by ADP, collagen, ristomycin, adrenaline was determined, as well as PTT, TT, aPTT, fibrinogen, and the clotting time.

Results and discussion. Introduction of resverаtrol and nicorandil resulted in a decrease in thrombocyte aggregation capacity from 53.8 ± 2.60% to 22.1 ± 1.25% and 37.1 ± 1.79%, respectively, when using ADP as an inducer. The clotting time was from 841 ± 42 s up to 1135 ± 33 s and 1034 ± 26 s, respectively. In addition, there was an increase in temporal parameters of plasma-coagulation hemostasis and a decrease in plasma fibrinogen content. The use of glibenclamide resulted in partial cancellation of the positive effects of resverаtrol and nicorandil, with an increase in platelet aggregation to 28.9 ± 1.8% and 43.9 ± 1.2% when using ADP as an inducer and a decrease in the thrombosis time to 988 ± 26 s and 950 ± 22 s, respectively.

Conclusion. In animals with experimental preeclampsia, there were disturbances in the hemostasis system, comparable to those in the clinical situation. The use of resverаtrol and nicorandil leads to a pronounced correction of hemostasis parameters. The positive effects of the studied pharmacological agents are mediated by several mechanisms, including K+ATP channels.

Platelet function in preeclampsia - a systematic review and meta-analysis

Preeclampsia is a serious pregnancy-related complication. Platelets are potentially important in the pathogenesis of preeclampsia, and platelet function analyses may prove as sensitive preeclampsia biomarkers. This study aimed to systematically review and summarise the literature on platelet function markers in preeclampsia. This systematic review was conducted according to PRISMA and registered in PROSPERO. Relevant studies were identified through PubMed and Embase on 15/08/17. As platelet function markers platelet activation, platelet aggregation and platelet adhesion markers were included. If possible, relevant data were extracted for each marker to perform a meta-analysis of the mean difference between women with and without preeclampsia. All 69 included articles underwent quality rating. Some platelet activation markers, especially p-selectin and mean platelet volume (MPV), were significantly increased comparing the two groups of women, while others were not. The meta-analysis demonstrated that, overall, women with preeclampsia had significantly higher MPV than in women without preeclampsia. No significant difference was found regarding platelet aggreg`ation comparing the two groups. Platelet adhesion was investigated in noneof the included studies. In conclusion, further studies are warranted to investigate platelet activation markers future role as predictive markers in preeclampsia. MPV is suggested as the most promising biomarker for evaluating platelet function in preeclampsia.

IQCA-TAVV: To explore the effect of P-selectin, GPIIb/IIIa, IL-2, IL-6 and IL-8 on deep venous thrombosis

Deep vein thrombosis (DVT) associates with considerable morbidity, functional disability and mortality. Due to the lack of suitable inhibitor the correlation of various factors in DVT onset remains unknown. In this context we analyzed the structure of anti-platelet aggregation agent, P-selectin down-regulator, GPIIb/IIIa down-regulator and anti-inflammatory agent, thereby designed N-(3S-1,2,3,4-tetrahydroisoquinoline-3-carbonyl)- Thr-Ala-Arg-Gly-Asp(Val)-Val (IQCA-TAVV) as an inhibitor of DVT to receive evaluations. The docking predicted that IQCA-TAVV can target P-selectin and GPIIb/IIIa. The UV showed that IQCA-TAVV can act on P-selectin and GPIIb/IIIa. ELISA indicated that IQCA-TAVV concentration dependently inhibited activated platelets to express P-selectin and GPIIb/IIIa, and the minimal effective concentration was 1 nM. IC50 of IQCA-TAVV against platelet aggregation induced by arachidonic acid, adenosine diphosphate and platelet activating factor fell within a range of 0.13 nM to 0.30 nM. In vivo IQCA-TAVV dose-dependently inhibited venous thrombosis and the minimal effective dose was 1 nmol/kg. On ear edema model the anti-inflammation activity of 10 nmol/kg IQCA-TAVV equaled that of 1.1mmol/kg aspirin. The concentration of IL-2, IL-6 and IL-8 in the serum of the ear edema mice were also significantly decreased by 10 nmol/kg IQCA-TAVV. Even at 1 μmol/kg of dose IQCA-TAVV still did not injure the kidney, the liver, and the nerves of healthy mice. Thereby IQCA-TAVV depicts a relationship of three levels (inhibiting platelet activation, targeting externalized membrane receptor, decreasing serum inflammatory factor) for the down-regulation of P-selectin, GPIIb/IIIa, IL-2, IL-6 and IL-8 in DVT.

Blood laboratory testing for early prediction of preeclampsia: chasing the finish line or at the starting blocks?

Preeclampsia (PE) affects 2-8% of pregnancies worldwide, thus representing an important cause of maternal and neonatal morbidity, up to death. Many studies have been designed to identify putative biomarkers for accurate and timely diagnosing PE, but only some of them were focused on specific and sensitive biomarkers for early prediction of this life-threatening condition. In particular, some prospective studies aimed to investigate the predictive role of circulating biomarkers before 20 weeks of gestation in the general pregnant population yielded conflicting results. This article is hence centered on results obtained in studies investigating the predictive performances of angiogenic, anti-angiogenic, inflammatory, endocrine, and epigenetic biomarkers. The available evidence suggests that angiogenic and anti-angiogenic molecules, in particular the sFlt1:PlGF ratio, may be considered the biomarkers with the best diagnostic performance in the second trimester. However, doubts remain about their use in clinical settings before the 20th gestational week. Even lower evidence is available for other biomarkers, due to the fact that some positive results have not been confirmed in ensuing investigations, whereas unresolved analytical issues still contribute to make their clinical reliability rather questionable. Differential expression of microRNAs seems also a promising evidence for early prediction of PE, but additional research and well-designed prospective studies are needed to identify and validate routine predictive tests. KEY MESSAGES Preeclampsia affects 2-8% of pregnant women worldwide, thus remaining one of the leading causes of maternal and neonatal morbidity and mortality. Several studies have investigated the predictive role of circulating biomarkers before 20th week of gestation with conflicting results. Additional research and well-designed prospective studies are needed to identify and validate predictive tests in clinical practice.