Periprostatic adipose tissue thromboinflammation triggers prostatic neoplasia in early metabolic impairment: Interruption by rivaroxaban.

AIMS: Prostate cancer is among the highest incidence malignancies in men with a prevalence rate increasing in parallel to the rising global trends in metabolic disorders. Whereas a sizeable body of evidence links metabolic impairment to negative prognosis of prostate cancer, the molecular mechanism underlying this connection has not been thoroughly examined. Our previous work showed that localized adipose tissue inflammation occurring in select adipose depots in early metabolic derangement instigated significant molecular, structural, and functional alterations in neighboring tissues underlying the complications observed at this stage. In this context, the periprostatic adipose tissue (PPAT) constitutes an understudied microenvironment with potential influence on the prostatic milieu. MAIN METHODS AND RESULTS: We show that PPAT inflammation occurs in early prediabetes with signs of increased thrombogenic activity including enhanced expression and function of Factor X. This was mirrored by early neoplastic alterations in the prostate with fibrosis, increased epithelial thickness with marked luminal cellular proliferation and enhanced formation of intraepithelial neoplasia. Significantly, interruption of the procoagulant state in PPAT by a 10-day anticoagulant rivaroxaban treatment not only mitigated PPAT inflammation, but also reduced signs of prostatic neoplastic changes. Moreover, rivaroxaban decreased the murine PLum-AD epithelial prostatic cell viability, proliferation, migration, and colony forming capacity, while increasing oxidative stress. A protease-activated receptor-2 agonist reversed some of these effects. SIGNIFICANCE: We provide some evidence of a molecular framework for the crosstalk between PPAT and prostatic tissue leading to early neoplastic changes in metabolic impairment mediated by upregulation of PPAT thromboinflammation.

Effects of the factor Xa inhibitor rivaroxaban on the differentiation of endothelial progenitor cells.

BACKGROUND: We evaluated the efficacy of the factor Xa inhibitor rivaroxaban on the differentiation ability of vascular endothelial progenitor cells (EPCs), which play roles in vascular injury repair and atherogenesis. Antithrombotic treatment in patients with atrial fibrillation undergoing percutaneous coronary intervention (PCI) is challenging, and current guidelines recommend oral anticoagulant monotherapy 1 year or more after PCI. However, biological evidence of the pharmacological effects of anticoagulants is insufficient. METHODS: EPC colony-forming assays were performed using peripheral blood-derived CD34-positive cells from healthy volunteers. Adhesion and tube formation of cultured EPCs were assessed in human umbilical cord-derived CD34-positive cells. Endothelial cell surface markers were assessed using flow cytometry, and Akt and endothelial nitric oxide synthase (eNOS) phosphorylation were examined using western blot analysis of EPCs. Adhesion, tube formation and endothelial cell surface marker expression was observed in EPCs transfected with small interfering RNA (siRNA) against protease-activated receptor (PAR)-2. Finally, EPC behaviors were assessed in patients with atrial fibrillation undergoing PCI in whom warfarin was changed to rivaroxaban. RESULTS: Rivaroxaban increased the number of large EPC colonies and increased the bioactivities of EPCs, including adhesion and tube formation. Rivaroxaban also increased vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2, Tie-2, and E-selectin expression as well as Akt and eNOS phosphorylation. PAR-2 knockdown increased the bioactivities of EPCs and endothelial cell surface marker expression. Patients in whom the number of large colonies increased after switching to rivaroxaban showed better vascular repair. CONCLUSIONS: Rivaroxaban increased the differentiation ability of EPCs, leading to potential advantages in the treatment of coronary artery disease.

[The role of direct oral anticoagulants in the management of cancer-associated thrombosis in 2020]. / Place des anticoagulants oraux directs dans la prise en charge de la maladie thromboembolique veineuse associée au cancer en 2020.

Direct oral anticoagulants, anti-IIa or anti-Xa, are widely used in the treatment and prevention of venous thromboembolic disease as well as in nonvalvular atrial fibrillation. Direct oral anticoagulants are characterized by a rapid onset of activity, a predictable response and a relatively wide therapeutic window. Nevertheless, theoretical drug interactions exist since direct oral anticoagulants are substrates of the transport protein P-glycoprotein and/or of isoforms of cytochromes P450 pathway. Direct oral anticoagulants do not have a marketing authorization for the treatment of cancer-associated thrombosis unlike low-molecular-weight heparins which remain the gold standard treatment today. However, recent studies have compared low-molecular-weight heparins to direct oral anticoagulants in the treatment of cancer-associated thrombosis. Results of these studies showed a non-inferiority of direct oral anticoagulants in the prevention of recurrent thromboembolic events but at the cost of an increased hemorrhagic risk, in particular for patients with gastrointestinal and urogenital cancers. Thus, international guidelines, unlike French guidelines, integrate them in first line of the therapeutic strategy of cancer patients. We are certainly entering an era of personalized therapy for cancer-associated thrombosis, considering cancer type and also the theoretical risk of drug interactions with anti-cancer treatments or supportive care.

Early initiation of a factor Xa inhibitor can attenuate tissue repair and neurorestoration after middle cerebral artery occlusion.

The timing of anti-coagulation therapy initiation after acute cardioembolic stroke remains controversial. We investigated the effects of post-stroke administration of a factor Xa inhibitor in mice, focusing on tissue repair and functional restoration outcomes. We initiated administration of rivaroxaban, a Xa inhibitor, immediately after permanent distal middle cerebral artery occlusion (pMCAO) in CB-17 mice harboring few leptomeningeal anastomoses at baseline. Rivaroxaban initiated immediately after pMCAO hindered the recovery of blood flow in ischemic areas by inhibiting leptomeningeal anastomosis development, and led to impaired restoration of neurologic functions with less extensive peri-infarct astrogliosis. Within infarct areas, angiogenesis and fibrotic responses were attenuated in rivaroxaban-fed mice. Furthermore, inflammatory responses, including the accumulation of neutrophils and monocytes/macrophages, local secretion of pro-inflammatory cytokines, and breakdown of the blood-brain barrier, were enhanced in infarct areas in mice treated immediately with rivaroxaban following pMCAO. The detrimental effects were not found when rivaroxaban was initiated after transient MCAO or on day 7 after pMCAO. Collectively, early post-stroke initiation of a factor Xa inhibitor may suppress leptomeningeal anastomosis development and blood flow recovery in ischemic areas, thereby resulting in attenuated tissue repair and functional restoration unless occluded large arteries are successfully recanalized.

Different Involvement of OAT in Renal Disposition of Oral Anticoagulants Rivaroxaban, Dabigatran, and Apixaban.

This study aimed to investigate the interactions of 3 anticoagulants, rivaroxaban, apixaban, and dabigatran, with 5 human solute carrier transporters, hOAT1, hOAT3, hOCT2, hOATP1B1, and hOATP1B3. Apixaban inhibited hOAT3, hOATP1B1, and hOATP1B3, and rivaroxaban inhibited hOAT3 and hOATP1B3, with IC50 values of >20 and >5 µM, respectively. The effect of dabigatran was negligible or very weak, so significant drug interactions at therapeutic doses are unlikely. Specific uptake of rivaroxaban was observed only in human and mouse OAT3-expressing cells. The Km for mouse Oat3 (mOat3) was 1.01 ± 0.70 µM. A defect in mOat3 reduced the kidney-to-plasma concentration ratio of rivaroxaban by 38% in mice. Probenecid treatment also reduced the kidney-to-plasma concentration ratio of rivaroxaban in rats by 73%. Neither mOat3 defect nor probenecid administration in rats reduced the renal clearance of rivaroxaban. The uptake of rivaroxaban by monkey kidney slices was temperature dependent and inhibited by probenecid but not by tetraethylammonium. Taken together, organic anion transporters, mainly OAT3, may mediate basolateral uptake of rivaroxaban in kidneys. hOAT3 could be an additional factor that differentiates the potential drug-drug interactions of the 3 anticoagulants in the urinary excretion process in clinical settings.

Novel oral anticoagulants in plastic surgery.

Novel oral anticoagulants (NOACs) have emerged as a good alternative to warfarin in the prevention of stroke for patients with atrial fibrillation. NOAC use is increasing rapidly; therefore, greater understanding of their use in the perioperative period is important for optimal care. Studies and reviews that reported on the use of NOACs were identified, with particular focus on the perioperative period. PubMed was searched for relevant articles published between January 2000 and August 2015. The inevitable rise in the use of NOACs such as rivaroxaban (Xarelto™), apixaban (Eliquis™), edoxaban (Lixiana™) and dabigatran (Pradaxa™) may present a simplified approach to perioperative anticoagulant management due to fewer drug interactions, rapidity of onset of action and relatively short half-lives. Coagulation status, however, cannot reliably be monitored and no antidotes are currently available. When planning for discontinuation of NOACs, special consideration of renal function is required. Advice regarding the management of bleeding complications is provided for consideration in emergency surgery. In extreme circumstances, haemodialysis may be considered for bleeding with the use of dabigatran. NOACs will increasingly affect operative planning in plastic surgery. In order to reduce the incidence of complications associated with anticoagulation, the management of NOACs in the perioperative period requires knowledge of the time of last dose, renal function and the bleeding risk of the planned procedure. Consideration of these factors will allow appropriate interpretation of the current guidelines.

Rivaroxaban Inhibits Angiotensin II-Induced Activation in Cultured Mouse Cardiac Fibroblasts Through the Modulation of NF-κB Pathway.

Cell migration, proliferation, and differentiation of cardiac fibroblasts (CFs) play a central role in cardiac fibrosis. Factor Xa (FXa)-dependent protease-activated receptor (PAR)-1 and PAR-2 have been reported as important targets in proinflammatory and fibroproliferative diseases. From this viewpoint, we aimed to investigate whether treatment of rivaroxaban, an approved oral direct FXa inhibitor, attenuates functional changes in angiotensin (Ang) II-induced mouse CFs.Confluent cultured mouse CFs were pretreated with or without rivaroxaban. Ang II-induced cell migration was decreased by 73% in rivaroxaban induced cells. Rivaroxaban inhibited Ang II-induced cell proliferation by 27% at 0.01 µg/ mL, 69% at 0.1 µg/mL, 71% at 1 µg/mL, and 69% at 5 µg/mL. In mouse cytokine array measuring 40 cytokines, the productions of interleukin-16, TIMP-1, and tumor necrosis factor-α (TNF-α) were significantly reduced with 0.1 µg/mL of rivaroxaban pretreatment (all P < 0.05). TIMP-1 levels in the culture supernatant measured by ELISA were also decreased by rivaroxaban pretreatment in Ang II-induced CFs (35% decrease at 0.01 µg/mL, 47% at 0.1 µg/mL, 47% at 1 µg/mL, and 57% at 5 µg/mL). In the dual reporter assay analysis, rivaroxaban inhibited various inflammatory signal pathways, including the nuclear factor-kappa B (NF-κB), active protein-1 (AP-1), and mitogen-activated protein kinase (MAPK) pathways (decreases of 82%, 78%, and 75%, respectively).These data suggest that rivaroxaban inhibits Ang II-induced functional activation in cultured mouse CFs via inhibiting NF-κB and MAPK/AP-1 signaling pathways, which may be a possible target of heart failure, through the antifibrotic and anti-inflammatory efficacy of rivaroxaban in Ang II-stimulated cardiac fibroblasts.