Bivalirudin Anticoagulant Therapy With or Without Platelet Glycoprotein IIb/IIIa Inhibitors During Transcatheter Coronary Interventional Procedures: A Meta-Analysis

Relationship of Platelet Glycoprotein IIb/IIIa and CD62P With Hypercoagulable State After Oncologic Surgery

The biomarkers for predicting venous thromboembolic events (VTEs) after oncologic surgery are still lacking. The current study aimed to analyze the relationships of CD62P and GP IIb/IIIa with hypercoagulation after oncologic surgery. A total of 76 patients with primary abdominopelvic tumors in our hospital were enrolled. The patients were divided into groups A (malignancy with no VTE group), B (malignancy with VTE group), and C (benign with no VTE group). Twenty healthy volunteers were selected as control. The plasma CD62P (4.69 ± 2.55 vs. 1.76 ± 0.48) and the GP IIb/IIIa (9.28 ± 3.79 vs. 1.76 ± 0.48) levels in group A were significantly higher than those in the control group preoperatively. The CD62P (31.46 ± 17.13 vs. 13.51 ± 7.43, P < 0.05), GP IIb/IIIa (42.33 ± 21.82 vs. 13.51 ± 7.43, P < 0.05), and D-dimer (7.33 ± 2.34 vs. 2.03 ± 0.55, P < 0.05) levels in group B were markedly higher 7 days after operation compared with those in group A. The CD62P and the GP IIb/IIIa exhibited a positive correlation with the hypercoagulable state after oncologic surgery.

Effects of Danhong Injection on platelet aggregation in hyperlipidemia rats

ETHNOPHARMACOLOGICAL RELEVANCE

Danhong Injection (DHI), a Chinese medical product extracted from Radix et Rhizoma Salviae Miltiorrhizae (Salvia miltiorrhiza Bge., Labiatae, Danshen in Chinese) and Flos Carthami (Carthamus tinctorius L., Compositae, Honghua in Chinese), has been reported to have effects on inflammatory, anti-fibrinolytic properties, antithrombotic and decrease blood-lipid. It is extensively used for the clinical treatment of cardiovascular disease. This study aimed to investigate the effects of DHI on blood-lipid levels and platelet aggregation rate in hyperlipidemia rats.

MATERIALS AND METHODS

Rats were randomly divided into 6 groups: normal control (NC), model control (MC), DHI-treated control at doses of 1.0mL/kg, 2.0mL/kg, 4.0mL/kg, respectively, and Simvastatin positive control at dose of 2.0mg/kg. All DHI treated groups were intraperitoneally injected for 7 days. The effects of DHI on serum triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) were evaluated. And platelet activating factor (PAF), platelet membrane glycoprotein IIb/IIIa (GP IIb/IIIa) and 6-keto-prostaglandin F1а (6-K-PGF1а) were determined by enzyme-linked immunosorbent assay (ELISA). Moreover, the expression of prostaglandin I-2 (PGI₂), prostaglandin E-2 (PGE₂) and thromboxane A2 (TXA₂) in liver was determined by real-time PCR.

RESULTS

Compared with the MC group, the rats treated with DHI had significantly reduced TC, TG, LDL-C, FIB, GP IIb/IIIa and platelet aggregation. Meanwhile, the thrombin time (TT), activated partial thrombin time (APTT), prothrombin time (PT), 6-K-PGF1а was significantly increased. Expression of PGI₂ and PGE₂ mRNA was significantly increased, whereas the TXA₂ was significantly reduced.

CONCLUSIONS

This study demonstrated that the blood lipid and platelet aggregation has a regulatory effect after DHI treatment. The insights gained from this study will improve understanding of the mechanisms involved in the effect of DHI on hyperlipidemia and the pharmacological rationale for the use of DHI in diseases caused by formation of thrombosis and lipid metabolic disorders.

On the value of therapeutic interventions targeting the complement system in acute myocardial infarction

The complement system plays an important role in the inflammatory response subsequent to acute myocardial infarction (AMI). The aim of this study is to create a systematic overview of studies that have investigated therapeutic administration of complement inhibitors in both AMI animal models and human clinical trials. To enable extrapolation of observations from included animal studies toward post-AMI clinical trials, ex vivo studies on isolated hearts and proof-of-principle studies on inhibitor administration before experimental AMI induction were excluded. Positive therapeutic effects in AMI animal models have been described for cobra venom factor, soluble complement receptor 1, C1-esterase inhibitor (C1-inh), FUT-175, C1s-inhibitor, anti-C5, ADC-1004, clusterin, and glycosaminoglycans. Two types of complement inhibitors have been tested in clinical trials, being C1-inh and anti-C5. Pexelizumab (anti-C5) did not result in reproducible beneficial effects for AMI patients. Beneficial effects were reported in AMI patients for C1-inhibitor, albeit in small patient groups. In general, despite the absence of consistent positive effects in clinical trials thus far, the complement system remains a potentially interesting target for therapy in AMI patients. Based on the study designs of previous animal studies and clinical trials, we discuss several issues which require attention in the design of future studies: adjustment of clinical trial design to precise mechanism of action of administered inhibitor, optimizing the duration of therapy, and optimization of time point(s) on which therapeutic effects will be evaluated.

A novel hirudin derivative inhibiting thrombin without bleeding for subcutaneous injection

Currently, anticoagulants would be used to prevent thrombosis. Thrombin is an effector enzyme for haemostasis and thrombosis. We designed a direct thrombin inhibitor peptide (DTIP) using molecular simulation and homology modelling and demonstrated that the C-terminus of DTIP interacts with exosite I, and N-terminus with the activity site of thrombin, respectively. DTIP interfered with thrombin-mediated coagulation in human, rat and mouse plasma (n=10 per group) and blocked clotting in human whole blood in vitro. When administered subcutaneously, DTIP showed potent and dose-dependent extension of aPTT, PT, TT and CT in rats (n=10 per group). The antithrombotic dose of DTIP induced significantly less bleeding than bivalirudin determined by transecting distal tail assay in rats. Furthermore, DTIP reached peak blood concentration in 0.5-1 hour and did not cause increased bleeding after five days of dosing compared to dabigatran etexilate. The antithrombotic effect of DTIP was evaluated in mice using lethal pulmonary thromboembolism model and FeCl₃-induced mesenteric arteriole thrombus model. DTIP (1.0 mg/kg, sc) prevented deep venous thrombosis and increased the survival rate associated with pulmonary thromboembolism from 30 % to 80 %. Intravital microscopy showed that DTIP (1.0 mg/kg, sc) decelerated mesenteric arteriole thrombosis caused by FeCl₃ injury. These data establish that DTIP is a novel antithrombotic agent that could be used to prevent thrombosis without conferring an increased bleeding risk.