endothelin-1 and Connective-Tissue-Diseases

The dual endothelin receptor antagonist, bosentan, is an orally active therapy, which is effective in the treatment of pulmonary arterial hypertension (PAH). This review critically appraises the evidence for the efficacy of bosentan in idiopathic and familial PAH, in PAH associated with connective tissue disease and in PAH which may develop in association with other conditions. Data from the pivotal placebo controlled studies and their open labeled extensions as well as long term survival and quality of life data is presented. Data is also presented on the potential benefit of bosentan in patients with inoperable chronic thromboembolic pulmonary hypertension. The safety and tolerability of bosentan as well as drug interactions are discussed. Dosage recommendations in adults and pediatrics are presented. An algorithm is provided to guide the reader in monitoring potential increases in alanine and aspartate transaminase levels that may occur with bosentan use and the dose adjustments that are recommended as a result of any increase in the levels of these enzymes are shown. Finally, the role of bosentan as part of combination therapy in PAH is examined.

Topics: Antihypertensive Agents; Bosentan; Connective Tissue Diseases; Dose-Response Relationship, Drug; Drug Interactions; Drug Therapy, Combination; Endothelin-1; Humans; Hypertension, Pulmonary; Pediatrics; Quality of Life; Sulfonamides

Vascular dysregulation is centrally involved in the pathogenesis of diverse rheumatological diseases. The resulting pulmonary arterial hypertension as well as Raynaud's phenomenon may be accompanied by distinct tissue fibrosis. The pleiotropic cytokine endothelin may represent a link between these vascular and fibrotic processes, which are most evidently seen in systemic sclerosis. Among three closely related isoforms, endothelin-1 (ET-1) is the most common in humans, and is often referred to as ET in the literature. ET-1 is involved in physiological processes of vascular tone and mitogenesis, whereas under pathological conditions fibrosis, vascular hypertension and inflammation are induced. Its expression is dependent on tissue and cell type as well as on the underlying disease entity and its stage. Elevated plasma and tissue levels have been demonstrated in idiopathic pulmonary hypertension, systemic sclerosis as well as in other connective tissue diseases and correlate to haemodynamic parameters and disease outcome. The biological effects are mediated by two membrane receptors (ET-1-receptor A and B) belonging to the G-protein-coupled serpentine family. Both receptors are differentially expressed by different cell types as well as in different diseases entities. Antagonizing these receptors therapeutically has already been successful. However, the differential action of ET is counterbalanced by other mediators, prominently nitric oxide. Consequently, the suspected direct relation of vascular and fibrotic processes through ET still needs to be further evaluated.

Topics: Cardiovascular System; Connective Tissue Diseases; Endothelin-1; Humans; Receptor, Endothelin A; Receptor, Endothelin B

Raynaud syndrome (RS) manifests as episodes of transient spasms of peripheral blood vessels, most often in response to cold. The reason of that symptom (primary RS (pRS)) usually cannot be found but may be accompanied by some autoimmune diseases (secondary RS (sRS)). In this study, we assessed microcapillary status and serum concentrations of chosen cytokines, adhesive molecules, and nitric oxide (NO) in patients with pRS and sRS in comparison with healthy children. Eighty-six patients with RS were enrolled into the study, including 52 with pRS and 34 with sRS. The control group consisted of 29 healthy children. A decrease in myorelaxative and anticoagulant abilities was observed, with simultaneous prevalence of vasopressor substances and procoagulative activity. Therefore, several important factors such as endothelin-1 (ET-1), E-selectin (E-sel), interleukin-18 (IL-18), and nitrogen oxide (NO) were also analyzed. Two types of capillaroscopy status were determined: normal and microangiopathic. There was a significant relationship between presence of microangiopathy and higher serum ET-1 (p = 0.018) and E-sel (p = 0.021) levels. Similarly, we have found a correlation between presence of ANA and higher ET-1 (p = 0.005), but not E-sel (p = 0.241). In patients with pRS, we found significant relationship between ANA and higher ET-1 (p = 0.008). No such relations were observed in sRS patients. Our data indicates that external factor-induced vasoconstrictive effects dominated in pRS, whereas in sRS in the course of connective tissue diseases, it was accompanied by coexistent vasodilation due to endothelial dysfunction. The latter phenomenon is at least partially dependent on insufficient NO release.

Topics: Adolescent; Case-Control Studies; Child; Connective Tissue Diseases; E-Selectin; Endothelin-1; Endothelium; Female; Humans; Interleukin-18; Male; Microcirculation; Microscopic Angioscopy; Nails; Nitrogen Oxides; Poland; Raynaud Disease

In the pathogenesis of Raynaud's phenomenon humoral and immunoinflammatory agents are involved. The aim of this study was the assessment of the level of endothelin-1 (ET-1), tumor necrosis factor (TNF-alpha), interleukin-6 (IL-6), soluble IL-6 receptor (IL-6sR), von Willebrand's factor (vWF) and platelet factor 4 (PF-4) in patients with Raynaud's phenomenon associated with systemic connective tissue diseases.. The examined group consisted of 32 patients (24 women and 8 men) with Raynaud's phenomenon associated with selected connective tissue diseases, aged 28-50 years. A control group consisted of 13 healthy volunteers. Immediately after a cold provocation test venous blood was taken in order to assess serum concentrations of: TNF-alpha, IL-6, IL-6sR, vWF, PF-4, antinuclear antibodies (ANA), antineutrophil antibodies (c-ANCA).. In the group of patients with Raynaud's phenomenon mean serum concentration of ET-1, TNF-alpha, PF-4, and vWF was significantly greater than in the healthy group. In contrast, serum IL-6 and IL-6sR concentrations did not differ significantly between the diseased and healthy groups. In a subgroup of Raynaud's phenomenon patients showing particularly high concentration of serum ET-1 (twice as much as mean control concentration), the increase in IL-6, IL-6sR, vWF and c-ANCA concentration exhibited statistical significance in comparison with patients with lower serum ET-1 concentration. The vWF concentration exhibited positive correlation with time interval between the occurrence of clinical symptoms and serum ANA antibodies concentration. The increase in ET-1 synthesis in Raynaud's phenomenon patients is dependent on the increase in IL-6 level and c-ANCA antibodies level.. The patients with Raynaud's phenomenon show an increase in ET-1 and TNF-alpha concentrations. An enhanced ET-1 synthesis is dependent on the augmentation of serum c-ANCA antibodies and IL-6 concentrations.

Topics: Adult; Antibodies, Antineutrophil Cytoplasmic; Antibodies, Antinuclear; Biomarkers; Connective Tissue Diseases; Cytokines; Disease Progression; Endothelin-1; Enzyme-Linked Immunosorbent Assay; Female; Follow-Up Studies; Humans; Interleukin-6; Male; Middle Aged; Platelet Factor 4; Raynaud Disease; Receptors, Interleukin-6; Severity of Illness Index; Tumor Necrosis Factor-alpha; von Willebrand Factor