Effects of Bosentan on Hypoxia, Inflammation and Oxidative Stress in Experimental Blunt Thoracic Trauma Model.

Background and Objectives: In this study, we aimed to investigate the effects of bosentan, an endothelin receptor antagonist, on endothelin-1 (ET-1), hypoxia-inducible factor-1 (HIF-1), nuclear factor-kappa B (NF-κB), and tumor necrosis factor (TNF)-α as inflammation markers, pro-oxidant antioxidant balance (PAB), and total antioxidant capacity (TAC) levels as oxidative stress parameters in lung tissues of rats in an experimental model of pulmonary contusion (PC) induced by blunt thoracic trauma. Materials and Methods: Thirty-seven male Sprague-Dawley rats were divided into five groups. C: The control group (n = 6) consisted of unprocessed and untreated rats. PC3 (n = 8) underwent 3 days of PC. PC-B3 (n = 8) received 100 mg/kg bosentan and was given orally once a day for 3 days. The PC7 group (n = 7) underwent 7 days of PC, and PC-B7 (n = 8) received 100 mg/kg bosentan and was given orally once a day for 7 days. Results: ET-1, NF-κB, TNF-α, HIF-1α, and PAB levels were higher, while TAC activity was lower in all groups compared with the control (p < 0.05). There was no significant difference in ET-1 and TNF-α levels between the PC-B3 and PC-B7 groups and the control group (p < 0.05), while NF-κB, HIF-1α, and PAB levels were still higher in both the PC-B3 and PC-B7 groups than in the control group. Bosentan decreased ET-1, NF-κB, TNF-α, HIF-1α, and PAB and increased TAC levels in comparison to the nontreated groups (p < 0.05). Conclusions: Bosentan decreased the severity of oxidative stress in the lungs and reduced the inflammatory reaction in rats with PC induced by blunt thoracic trauma. This suggests that bosentan may have protective effects on lung injury mechanisms by reducing hypoxia, inflammation, and oxidative stress. If supported by similar studies, bosentan can be used in both pulmonary and emergency clinics to reduce ischemic complications, inflammation, and oxidative stress in some diseases that may be accompanied by ischemia.

The Anti-Atherosclerotic Effects of Endothelin Receptor Antagonist, Bosentan, in Combination with Atorvastatin-An Experimental Study.

Bosentan, an endothelin receptor antagonist (ERA), has potential anti-atherosclerotic properties. We investigated the complementary effects of bosentan and atorvastatin on the progression and composition of the atherosclerotic lesions in diabetic mice. Forty-eight male ApoE-/- mice were fed high-fat diet (HFD) for 14 weeks. At week 8, diabetes was induced with streptozotocin, and mice were randomized into four groups: (1) control/COG: no intervention; (2) ΒOG: bosentan 100 mg/kg/day per os; (3) ATG: atorvastatin 20 mg/kg/day per os; and (4) BO + ATG: combined administration of bosentan and atorvastatin. The intra-plaque contents of collagen, elastin, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-a (TNF-a), matrix metalloproteinases (MMP-2, -3, -9), and TIMP-1 were determined. The percentage of lumen stenosis was significantly lower across all treated groups: BOG: 19.5 ± 2.2%, ATG: 12.8 ± 4.8%, and BO + ATG: 9.1 ± 2.7% compared to controls (24.6 ± 4.8%, p < 0.001). The administration of both atorvastatin and bosentan resulted in significantly higher collagen content and thicker fibrous cap versus COG (p < 0.01). All intervention groups showed lower relative intra-plaque concentrations of MCP-1, MMP-3, and MMP-9 and a higher TIMP-1concentration compared to COG (p < 0.001). Importantly, latter parameters presented lower levels when bosentan was combined with atorvastatin compared to COG (p < 0.05). Bosentan treatment in diabetic, atherosclerotic ApoE-/- mice delayed the atherosclerosis progression and enhanced plaques' stability, showing modest but additive effects with atorvastatin, which are promising in atherosclerotic cardiovascular diseases.

Is endothelin targeting finally ready for prime time?

The endothelin family of peptides has long been recognized as a physiological regulator of diverse biological functions and mechanistically involved in various disease states, encompassing, among others, the cardiovascular system, the kidney, and the nervous system. Pharmacological blockade of the endothelin system, however, has encountered strong obstacles in its entry into the clinical mainstream, having obtained only a few proven indications until recently. This translational gap has been attributable predominantly to the relevant side effects associated with endothelin receptor antagonism (ERA), particularly fluid retention. Of recent, however, an expanding understanding of the pathophysiological processes involving endothelin, in conjunction with the development of new antagonists of endothelin receptors or adjustment of their doses, has driven a flourish of new clinical trials. The favorable results of some of them have extended the proven indications for ET targeting to a variety of clinical conditions, including resistant arterial hypertension and glomerulopathies. In addition, on the ground of strong preclinical evidence, other studies are ongoing to test the potential benefits of ERA in combination with other treatments, such as sodium-glucose co-transporter 2 inhibition in fluid retentive states or anti-cancer therapies in solid tumors. Furthermore, antibodies providing long-term blockade of endothelin receptors are under testing to overcome the short half-life of most small molecule endothelin antagonists. These efforts may yet bring new life to the translation of endothelin targeting strategies in clinical practice.

Endothelin System in Hypertension and Chronic Kidney Disease.

ET (endothelin) is a powerful vasoconstrictor 21-amino acid peptide present in many tissues, which exerts many physiological functions across the body and participates as a mediator in many pathological conditions. ETs exert their effects through ETA and ETB receptors, which can be blocked by selective receptor antagonists. ETs were shown to play important roles among others, in systemic hypertension, particularly when resistant or difficult to control, and in pulmonary hypertension, atherosclerosis, cardiac hypertrophy, subarachnoid hemorrhage, chronic kidney disease, diabetic cardiovascular disease, scleroderma, some cancers, etc. To date, ET antagonists are only approved for the treatment of primary pulmonary hypertension and recently for IgA nephropathy and used in the treatment of digital ulcers in scleroderma. However, they may soon be approved for the treatment of patients with resistant hypertension and different types of nephropathy. Here, the role of ETs is reviewed with a special emphasis on participation in and treatment of hypertension and chronic kidney disease.

Advances in the discovery of drugs that treat pulmonary arterial hypertension.

INTRODUCTION: Distal pulmonary arterial remodeling and elevated pulmonary vascular resistance are characteristic of pulmonary arterial hypertension (PAH). Current approved vasodilator-specific PAH therapy that includes phosphodiesterase-5 inhibitors, soluble guanylate cyclase stimulators, endothelin receptor antagonists, and prostanoids has demonstrated dramatic enhancement in functional capacity, quality of life, and invasive hemodynamics. However, none of these treatments are curative, underscoring the need to identify new pathophysiologic signaling pathways. AREAS COVERED: The author provides a comprehensive review on current knowledge and recent development in the understanding of PAH. Furthermore, the author discusses PAH potential genetic causes as well as novel molecular signaling pathways. This article also reviews the currently approved PAH specific therapy based on pivotal clinical trials and ongoing clinical trials using novel compounds that specifically target PAH pathogenesis. EXPERT OPINION: The discovery of novel signaling pathways - growth factors, tyrosine kinases, BMPs, estrogen, and serotonin - involved in the PAH pathobiology will lead within the next 5 years to the approval of new therapeutic agents targeting these different pathways. If proven beneficial, these new agents may reverse or at least prevent the progression of this devastating and lethal disease.

Pharmacological counseling in hepatotoxicity induced by macitentan and selexipag: a case report.

BACKGROUND: Pulmonary arterial hypertension is a progressive, debilitating condition characterized by increased resistance in the pulmonary arterial circulation. Current treatments for pulmonary arterial hypertension include endothelin receptor antagonists such as bosentan, sitaxentan, ambrisentan, macitentan, and oral prostacyclin receptor agonists such as selexipag. Endothelin receptor antagonists have been associated with liver injury, while hepatotoxicity was not reported for selexipag. Although genetic variability has been indisputably associated with variability in drug response, no study has been designed until now to assess its effects on the pharmacokinetics of endothelin receptor antagonists or selexipag. CASE PRESENTATION: We report the case of a 58-year-old female Caucasian patient with a dramatic increase in plasma levels of transaminases after treatment with macitentan and selexipag, drugs whose risk of causing liver injury has so far been considered limited. After therapy discontinuation, plasma levels of transaminases returned to baseline, thus suggesting a role of these drugs in the observed hepatotoxicity. After pharmacological counseling, we decided to introduce ambrisentan for the patient's treatment. After 7 months of treatment, no liver injury has been reported. To evaluate the role of genetic factors in the observed hepatotoxicity, we genotyped the patient for single-nucleotide polymorphisms previously associated with macitentan, ambrisentan, or selexipag metabolism. We found a genetic profile associated with a poor metabolizer (PM) phenotype for CYP2C8 and CYP2C9, key enzymes for elimination of both macitentan and selexipag. The reported results suggest that an allelic profile associated with low activity for CYP2C8 and CYP2C9 enzyme could be a potential risk factor for macitentan and selexipag-induced liver injury and could provide a possible marker for early identification of subjects at higher risk of developing hepatotoxicity. CONCLUSIONS: A multidisciplinary approach based on clinical evaluation, as well as pharmacological counseling and evaluation of the patient's genetic profile, might be useful for identification of patients with a high chance of drug-induced liver injury, avoiding unnecessary risks in therapy selection and prescription.

The potential benefit of endothelin receptor antagonists' therapy in idiopathic pulmonary fibrosis: A meta-analysis of results from randomized controlled trials.

BACKGROUND: Fibrotic diseases take a very heavy toll in terms of morbidity and mortality equal to or even greater than that caused by metastatic cancer. This meta-analysis aimed to evaluate the effect of endothelin receptor antagonists on idiopathic pulmonary fibrosis. METHOD: A systematic search of the clinical trials from the Medline, Google Scholar, Cochrane Library, and PubMed electronic databases was performed. Stata version 12.0 statistical software (Stata Crop LP, College Station, TX) was adopted as statistical software. RESULT: A total of 5 studies, which included 1500 participants. Our analysis found there is no significant difference between using the endothelin receptor antagonists' group and placebo groups regarding the lung function via estimating both the change of forced vital capacity from baseline and DLco index. Exercise capacity and serious adverse effects are taken into consideration as well; however, there is still no significant change between the 2 groups. CONCLUSION: This meta-analysis provides insufficient evidence to support that endothelin receptor antagonists' administration provides a benefit among included participants who encounter idiopathic pulmonary fibrosis.

Endothelin-axis antagonism enhances tumor perfusion in pancreatic cancer.

Delivery of therapeutic agents in pancreatic cancer (PC) is impaired due to its hypovascular and desmoplastic tumor microenvironment. The Endothelin (ET)-axis is the major regulator of vasomotor tone under physiological conditions and is highly upregulated in multiple cancers. We investigated the effect of dual endothelin receptor antagonist bosentan on perfusion and macromolecular transport in a PC cell-fibroblast co-implantation tumor model using Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI). Following bosentan treatment, the contrast enhancement ratio and wash-in rates in tumors were two- and nine times higher, respectively, compared to the controls, whereas the time to peak was significantly shorter (7.29 ± 1.29 min v/s 22.08 ± 5.88 min; p = 0.04). Importantly, these effects were tumor selective as the magnitudes of change for these parameters were much lower in muscles. Bosentan treatment also reduced desmoplasia and improved intratumoral distribution of high molecular weight FITC-dextran. Overall, these findings support that targeting the ET-axis can serve as a potential strategy to selectively enhance tumor perfusion and improve the delivery of therapeutic agents in pancreatic tumors.

Pulmonary hypertension in bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) is a major complication in prematurely born infants. Pulmonary hypertension (PH) associated with BPD (BPD-PH) is characterized by alveolar diffusion impairment, abnormal vascular remodeling, and rarefication of pulmonary vessels (vascular growth arrest), which lead to increased pulmonary vascular resistance and right heart failure. About 25% of infants with moderate to severe BPD develop BPD-PH that is associated with high morbidity and mortality. The recent evolution of broader PH-targeted pharmacotherapy in adults has opened up new treatment options for infants with BPD-PH. Sildenafil became the mainstay of contemporary BPD-PH therapy. Additional medications, such as endothelin receptor antagonists and prostacyclin analogs/mimetics, are increasingly being investigated in infants with PH. However, pediatric data from prospective or randomized controlled trials are still sparse. We discuss comprehensive diagnostic and therapeutic strategies for BPD-PH and briefly review the relevant differential diagnoses of parenchymal and interstitial developmental lung diseases. In addition, we provide a practical framework for the management of children with BPD-PH, incorporating the modified definition and classification of pediatric PH from the 2018 World Symposium on Pulmonary Hypertension, and the 2019 EPPVDN consensus recommendations on established and newly developed therapeutic strategies. Finally, current gaps of knowledge and future research directions are discussed. IMPACT: PH in BPD substantially increases mortality. Treatment of BPD-PH should be conducted by an interdisciplinary team and follow our new treatment algorithm while still kept tailored to the individual patient. We discuss recent developments in BPD-PH, make recommendations on diagnosis, monitoring and treatment of PH in BPD, and address current gaps of knowledge and potential research directions. We provide a practical framework, including a new treatment algorithm, for the management of children with BPD-PH, incorporating the modified definition and classification of pediatric PH (2018 WSPH) and the 2019 EPPVDN consensus recommendations on established and newly developed therapeutic strategies for BPD-PH.

Outcome of paediatric portopulmonary hypertension in the modern management era: A case report of 6 patients.

Portopulmonary hypertension is a rare but serious complication of portal hypertension or portosystemic shunting. Portopulmonary hypertension is an indication for liver transplantation or shunt closure. However, liver transplantation is contraindicated in patients with severe pulmonary arterial hypertension. Reported mortality rates are high in children with portopulmonary hypertension and there are scarce recommendations on its management. Our aim was to report on our real-world experience of managing portopulmonary hypertension in a specialised centre. We describe a series of 6 children with portopulmonary hypertension. Their median age at diagnosis was 13 years (range 10-15). The underlying liver conditions were cirrhosis of unknown origin (1), congenital portocaval shunts (3), biliary atresia (1), and portal vein cavernoma with surgical mesenterico-caval shunt (1). Median mean pulmonary arterial pressure was 47 mmHg (range 32-70), and median pulmonary vascular resistance was 6.6 Wood units (range 4.3-15.4). All patients except one were treated with a combination of pulmonary arterial hypertension-specific therapy (phosphodiesterase type 5 inhibitors and/or endothelin receptor antagonists and/or prostacyclin analogues). Three patients then benefited from shunt closure and the others underwent liver transplantation. Five patients showed improvement or stabilisation of pulmonary arterial hypertension with no deaths after a mean follow-up of 39 months. Based on our limited experience, early and aggressive treatment with a combination of pulmonary arterial hypertension-specific therapy significantly improves patients' haemodynamic profile and enables the performance of liver transplantation and shunt closure with satisfactory outcomes.

Effects of endothelin receptor blockade and COX inhibition on intestinal I/R injury in a rat model: Experimental research.

BACKGROUND: Intestinal ischemia is a highly morbid and mortal condition with no specific treatment. The present study aimed to investigate the effects of cyclooxygenase (COX) inhibition synchronized with nitric oxide (NO) release and endothelin (ET) receptor blockade on oxidative stress, inflammation, vasoconstriction, and bacterial translocation which occur during ischemia-reperfusion (I/R) injury in in-vivo rat intestinal I/R model. MATERIALS AND METHODS: 36 male Wistar rats were randomly divided into six groups (n = 6). Superior mesenteric artery blood flow (SMABF) was recorded; SMA was occluded for 30 min; SMABF was re-recorded at the beginning of the reperfusion phase. Rats were sacrificed after the reperfusion period of 60 min. Blood and tissue samples were obtained. Acetylsalicylic acid (ASA), NO-ASA, flurbiprofen (FLUR), and Tezosentan (TS) were administered 15 min after ischemia. Histopathological examination, bacterial translocation, and biochemical analysis were performed in plasma and tissue samples. RESULTS: SMABF difference, mean Chiu's score and bacterial translocation were increased in the I/R group and decreased in the treatment groups. Plasma LDH, transaminases, intestinal fatty acid-binding protein (I-FABP), TNF-α, ICAM-1, interferon-gamma (IFN-Ɣ) and proinflammatory cytokine panel; tissue lipid peroxidation, MPO, xanthine oxidase (XO), NO, NF-kB levels and the expression of TNF-α were significantly elevated in the I/R group and markedly decreased in the treatment groups. The tissue antioxidant status was decreased in the I/R group and increased in the treatment groups. CONCLUSION: It is suggested that NO-ASA, TS, and FLUR can be introduced as promising therapeutics to improve intestinal I/R injury. INSTITUTIONAL PROTOCOL NO: 2018-29-05 (Animal Experimentations Ethics Committee, Hacettepe University).

Effects of Multiple-Dose Administration of Aprocitentan on the Pharmacokinetics of Rosuvastatin.

Aprocitentan is an investigational, orally active, dual, endothelin receptor antagonist that targets a novel pathway in the treatment of difficult-to-control (resistant) hypertension. The drug-drug interaction potential of aprocitentan on the breast cancer resistance protein (BCRP) transporter substrate rosuvastatin was investigated in this single-center, open-label, single-sequence study. Twenty healthy male subjects received a single dose of 10-mg rosuvastatin on days 1 and 13 followed by pharmacokinetic and tolerability assessments for up to 120 hours. From day 5 to day 17, subjects received 25 mg of aprocitentan once daily. Seventeen of 20 enrolled subjects completed the treatment. At steady state, aprocitentan did not affect the pharmacokinetics of rosuvastatin in a clinically relevant way. The maximum plasma concentration was increased by 40% with a 90% confidence interval of 1.19 to 1.65. However, the ratio of the geometric means for both area under the plasma concentration-time curve from time 0 to time t and area under the plasma concentration-time curve from time 0 to infinity was close to 1 with the 90% confidence interval within a reference interval of 0.80 to 1.25. Adverse events leading to study discontinuation were reported in 2 subjects. Overall, the combination of rosuvastatin and aprocitentan was well tolerated. Based on these data, aprocitentan does not affect BCRP and can be administered concomitantly with drugs dependent on BCRP transport.

Expert Perspectives On Clinical Challenges: Expert Perspectives: Challenges in Scleroderma.

You are consulted to evaluate a 56-year-old woman with known Raynaud's phenomenon, finger swelling of several; months' duration, and new hypertension with a blood pressure of 160/100 mm/Hg. She also reports progressive shortness of breath. Physical examination reveals telangiectasias, sclerodactyly, and proximal skin sclerosis (thick shiny skin on the chest and upper arms), and bibasilar crackles are found on chest examination. Laboratory tests reveal evidence of microangiopathic hemolytic anemia, thrombocytopenia, and elevation of the serum creatinine level (previously normal), and chest computed tomography shows evidence of ground-glass opacification in both lower lung fields.

COVID-19 and Kidney Disease: Molecular Determinants and Clinical Implications in Renal Cancer.

CONTEXT: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic that erupted in December 2019 has affected more than a million people from over 200 countries, claiming over 70 000 lives (by April 7, 2020). As the viral infection is driven by increased angiotensin-converting enzyme-2 (ACE2) expression, with the kidney exhibiting the highest expression, it is crucial to gain insights into the mechanisms underlying renal cell carcinoma (RCC) and coronavirus disease 2019 (COVID-19). OBJECTIVE: This study considers up-to-date information on the biological determinants shared by COVID-19 and renal disease, and aims to provide evidence-based recommendations for the clinical management of RCC patients with COVID-19. EVIDENCE ACQUISITION: A literature search was performed using all sources (MEDLINE, EMBASE, ScienceDirect, Cochrane Libraries, and Web of Science). As of March 31, 2020, the Center for Disease Control reported that of the adults hospitalized for COVID-19 with underlying conditions in the USA, 74.8% had chronic renal disease. EVIDENCE SYNTHESIS: Evidence is discussed from epidemiological studies on SARS-CoV-2 pandemic and molecular studies on the role of kidney in facilitating routes for SARS-CoV-2 entry, leading to increased virulence of SARS-CoV-2 and clinical manifestation of symptoms in RCC. CONCLUSIONS: This analysis will advance our understanding of (1) the molecular signatures shared by RCC and COVID-19 and (2) the clinical implications of overlapping signaling pathways in the therapeutic management of RCC and COVID-19 patients. PATIENT SUMMARY: Amid the coronavirus disease 2019 (COVID-19) pandemic, patients diagnosed with renal cell carcinoma and infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may receive complimentary treatment modalities to enhance therapeutic response.

Use of medical therapies before pulmonary endarterectomy in chronic thromboembolic pulmonary hypertension patients with severe hemodynamic impairment.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare complication of acute pulmonary embolism, characterized by non-resolving fibro-thrombotic obstructions of large pulmonary arteries. Pulmonary endarterectomy (PEA) is the treatment of choice for the disease, significantly improving survival. Patients with worse hemodynamic profile have worse prognosis after surgery, raising the question of whether the use of medical therapy prior to surgery to optimize hemodynamics could improve outcomes. The aim of this study was to evaluate the role of medical therapy pre-PEA, according to the hemodynamic profile at the diagnosis. We retrospectively analyzed all patients submitted to PEA, from January 2013 to December 2017. Functional, clinical and hemodynamic data were collected to evaluate the main prognostic determinants. Patients were stratified according to the hemodynamic severity and use of targeted therapies prior to surgery. A total of 108 patients were included. Thirty-five patients (32,4%) used targeted therapy pre-PEA. The use of medical therapy delayed the surgical procedure by about 7 months. There was no difference in overall survival between patients that received targeted therapy and those treated only with supportive therapy (87.8% vs 80.3%, respectively, p = 0.426). Nevertheless, when analyzing the group of patients with severe hemodynamic impairment, defined by low cardiac output(<3.7L/min) at baseline, patients treated with targeted therapies presented a significantly better one-year survival. In higher-risk CTEPH patients, characterized by the presence of low cardiac output, the use of targeted therapies prior to PEA was associated with better outcome, suggesting a potential role for pre-operative use of medical treatment in this particular subgroup.

Endothelin-1, endothelin receptor antagonists, and vein graft occlusion in coronary artery bypass surgery: 20 years on and still no journey from bench to bedside.

The saphenous vein is the most commonly used bypass graft in patients with coronary artery disease. During routine coronary artery bypass, grafting the vascular damage inflicted on the vein is likely to stimulate the release of endothelin-1, a potent endothelium-derived vasoconstrictor that also possesses cell proliferation and inflammatory properties, conditions associated with vein graft failure. In both in vitro and in vivo studies, endothelin receptor antagonists reduce neointimal thickening. The mechanisms underlying these observations are multifactorial and include an effect on cell proliferation and cell/tissue damage. Much of the data supporting the beneficial action of endothelin-1 receptor antagonism at reducing intimal thickening and occlusion in experimental vein grafts were published over 20 years ago. The theme of the recent ET-16 conference in Kobe was "Visiting Old and Learning New". This short review article provides an overview of studies showing the potential of endothelin receptor antagonists to offer an adjuvant therapeutic approach for reducing saphenous vein graft failure and poses the question why this important area of research has not been translated from bench to bedside given the potential benefit for coronary artery bypass patients.

Antagonistas do receptor de endotelina para o tratamento de pacientes com COVID-19 / Endothelin receptor antagonists for or treatment of patients with COVID-19

CONTEXTO: Dada a pandemia do COVID-19, identificou-se a necessidade de pesquisar medicamentos que atuem na função pulmonar como possíveis tratamentos para a doença, entre eles os antagonistas de endotelina. Por inibirem os receptores de endotelina (um neuro hormônio de concentração elevada no tecido pulmonar), localizados principalmente nas células do músculo liso vascular pulmonar e nas células endoteliais vasculares pulmonares, estes agentes bloqueiam a vasoconstrição e a proliferação celular local, diminuindo o remodelamento tecidual e a resistência pulmonar e aumentando o débito cardíaco. Desta forma, estes agentes podem representar um alvo terapêutico para a doença. OBJETIVOS: Identificar, avaliar sistematicamente e sumarizar as melhores evidências científicas disponíveis sobre a eficácia e a segurança dos antagonistas do receptor de endotelina para COVID-19. MÉTODOS: Revisão sistemática rápida (rapid review methodology). RESULTADOS: Foram identificados 2.051 estudos, dos quais nenhum foi incluído após o processo de seleção. Não foram identificados estudos finalizados ou em andamento que pesquisassem a classe como um possível alvo para o tratamento da COVID-19. CONCLUSÃO: Esta revisão sistemática rápida não identificou estudos que avaliassem os efeitos dos antagonistas do receptor de endotelina para o tratamento da COVID-19. Deste modo, até que resultados de estudos clínicos com esta finalidade estejam disponíveis, não é possível estimar a eficácia e a segurança desses medicamentos no tratamento de pacientes com COVID-19, tampouco recomendar seu uso rotineiro para esta situação.(AU)

Portopulmonary hypertension in the current era of pulmonary hypertension management.

BACKGROUND & AIMS: Long-term outcomes in portopulmonary hypertension (PoPH) are poorly studied in the current era of pulmonary hypertension management. We analysed the effect of pulmonary arterial hypertension (PAH)-targeted therapies, survival and predictors of death in a large contemporary cohort of patients with PoPH. METHODS: Data from patients with PoPH consecutively enrolled in the French Pulmonary Hypertension Registry between 2007 and 2017 were collected. The effect of initial treatment strategies on functional class, exercise capacity and cardiopulmonary haemodynamics were analysed. Survival and its association with PAH- and hepatic-related characteristics were also examined. RESULTS: Six hundred and thirty-seven patients (mean age 55 ± 10 years; 58% male) were included. Fifty-seven percent had mild cirrhosis, i.e. Child-Pugh stage A. The median model for end-stage liver disease (MELD) score was 11 (IQR 9-15). Most patients (n = 474; 74%) were initiated on monotherapy, either with a phosphodiesterase-5 inhibitor (n = 336) or with an endothelin-receptor antagonist (n = 128); 95 (15%) were initiated on double oral combination therapy and 5 (1%) on triple therapy. After a median treatment time of 4.5 months, there were significant improvements in functional class (p <0.001), 6-minute walk distance (6MWD) (p <0.0001) and pulmonary vascular resistance (p <0.0001). Overall survival rates were 84%, 69% and 51% at 1, 3 and 5 years, respectively. Baseline 6MWD, sex, age and MELD score or Child-Pugh stage were identified as independent prognostic factors. Survival from PoPH diagnosis was significantly better in the subgroup of patients who underwent liver transplantation (92%, 83% and 81% at 1, 3 and 5 years, respectively). CONCLUSION: Survival of patients with PoPH is strongly associated with the severity of liver disease. Patients who underwent liver transplantation had the best long-term outcomes. LAY SUMMARY: Portopulmonary hypertension is defined by the presence of pulmonary arterial hypertension in the context of chronic liver disease and is characterized by progressive shortness of breath and exercise limitation. The presence of severe pulmonary arterial hypertension in liver transplant candidates represents a contraindication for such a surgery; however, treatments targeting pulmonary arterial hypertension are efficacious, allowing for safe transplantation and conferring good survival outcomes in those who undergo liver transplantation.

Current and Future Outlook on Disease Modification and Defining Low Disease Activity in Systemic Sclerosis.

Systemic sclerosis (SSc) is an autoimmune rheumatic disease with heterogeneous clinical manifestations and a variable course in which the severity of the pathology dictates the disease prognosis and course. Among autoimmune rheumatic diseases, SSc has the highest mortality rate among all rheumatic diseases, though there are exciting new therapeutic targets that appear to halt the progression of SSc manifestations such as skin or lung fibrosis. In selected patients, high-intensity regimens with autologous stem cell transplantation can favorably modify the course. In what was once thought to be an untreatable disease, targeted therapies have now changed the outlook of SSc to a treatable disorder. Herein, we discuss the targeted therapies modifying the outlook on selected organ involvement and creating opportunities for future treatment. We also present a framework for defining low disease activity in SSc.

Investigation of Bosentan's Effects on Pulmonary Contusion Created by Blunt Thoracic Trauma in Rats.

INTRODUCTION: Bosentan is an endothelin-1 receptor antagonist with anti-inflammatory, antioxidant, and antiproliferative effects. We aimed to evaluate its effects on lung tissue in a pulmonary contusion (PC) model. MATERIALS AND METHODS: The rats were randomly divided into five groups: PC3: PC evaluated on the 3rd day (n = 8), PC-B3: PC enteral bosentan 100 mg/kg/day, for 3 days (n = 8), PC7: PC evaluated on the 7th day (n = 7), PC-B7: PC 7 days bosentan 100 mg/kg/day, for 7 days (n = 8), C: control (n = 6). Unilateral lung contusion was created by dropping a metal weight onto the chest. The rats were sacrificed on the 3rd or the 7th days. The lung tissue was evaluated histopathologically for alveolar edema, congestion, and leukocyte infiltration, biochemically for malondialdehyde (MDA), superoxide dismutase (SOD), and nitric oxide (NO) levels, and immunohistochemically for inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), and apoptosis scores. RESULTS: Alveolar edema, congestion, and leukocyte infiltration scores were increased in all groups compared with the control group (p < 0.05) and decreased in bosentan-treated groups compared with the relevant nontreated groups (p < 0.05). Fibrosis was observed only in PC7 and PC-B7 groups. Bosentan did not have any effect on fibrosis development. iNOS and eNOS levels were higher in all groups compared with the control (p < 0.05) without a difference in the nontreated versus treated groups (p > 0.05). Bosentan treatment caused decreased MDA and increased SOD levels in comparison to the nontreated groups (p < 0.05). Tissue NO levels did not show any significant difference among groups. PC groups had higher levels of apoptosis compared with the control group (p < 0.05). The degree of apoptosis decreased in bosentan-treated groups compared with the nontreated groups (p < 0.05). CONCLUSION: PC causes progressive lung tissue damage. Bosentan reduced leukocyte infiltration and alveolar edema and congestion caused by PC. It also decreased MDA levels and increased SOD levels. Bosentan prevents tissue damage by inhibiting acute inflammatory response and reduces oxidative stress secondary to inflammation. It has therapeutic effects on apoptosis.