Upregulation of Endothelin-1/Endothelin A Receptor Expression Correlates with Heparanase Expression in Ovarian Carcinoma.

BACKGROUND: Heparanase and endothelin-1/endothelin A receptor (ET-1/ETAR) expressions increase in cancer. This condition enhances tumor progression and correlates with poor survival. Limited data are documented regarding the role of heparanase and ET-1/ETAR in epithelial ovarian cancer (EOC). We sought to characterize the correlation between heparanase and ET-1/ETAR in EOC. METHODS: Thirty patients with benign and malignant ovarian neoplasms were recruited in this study. Neoplasm subtypes were diagnosed by pathologists. RNA extraction was done in fresh frozen neoplasms while immunohistochemical (IHC) staining was done on ETAR, heparanase, and proliferation (Ki-67 antigen) in paraffin sections. Reverse transcriptase PCR was done to quantify the expression of preproET-1 (ppET-1), ETAR, and heparanase. ETAR and heparanase histoscores were done based on IHC staining. The Independent Samples t Test, ANOVA, and correlations were used for statistical analysis. RESULTS: Heparanase and ETAR histoscores, ppET-1 and ETAR mRNA levels, and Ki-67 were significantly higher in the group with EOC than in the benign or borderline group, regardless of the histopathological types. The heparanase histoscore correlated with the ETAR histoscore (r=0.484, P=0.007) and the ETAR mRNA level (r=0.551, P=0.003). The level of ppET-1 mRNA correlated with both ETAR mRNA level and ETAR histoscore (r=0.603, P=0.001 and r=0.455, P=028, respectively). The ovarian neoplasms with high ppET-1 mRNA levels also tended to have high heparanase mRNA levels; however, the correlation was weak (r=0.354, P=0.07). Ki-67 correlated with the heparanase and ETAR histoscores (r=0.381, P=0.038 and r=0.477, P=0.008, respectively). CONCLUSION: Heparanase and ETAR were upregulated in EOC, and the correlation between heparanase and ETAR expressions was also elucidated in the current study.

Activation of Receptor Activator of Nuclear Factor-κB Ligand and Matrix Metalloproteinase Production in Periodontal Fibroblasts by Endothelin Signaling.

BACKGROUND: Periodontitis is a group of inflammatory diseases affecting the tissues supporting the teeth that will progressively cause the loss of alveolar bone and periodontal ligaments and eventually the dentition. Activation of osteoclast activity by receptor activator of nuclear factor-κB ligand (RANKL) and released enzymes such as matrix metalloproteinases (MMPs) are among the factors involved in the breakdown of the periodontium. However, the mechanisms regulating their production in periodontitis are poorly understood. Endothelin signaling via the activation of the endothelin-A receptor (EDNRA) by endothelin-1 may play a role in the disease because the expression of the receptor and ligand is elevated in the periodontal tissues of patients with periodontitis. METHODS: Cultured primary human periodontal fibroblasts were treated with 20 and 100 nM endothelin-1 for 6 and 24 hours and then collected to assess MMP and RANKL production by immunoblotting. Inhibitors were used to identify the molecular pathways activated by EDNRA in these cells. RESULTS: Endothelin-1 stimulated the production of MMP1, MMP8, and RANKL in a dose- and time-dependent manner; blocking EDNRA function with the antagonist TBC3214 inhibited the response, although EDNRA activation had no effects on osteoprotegerin production. These mechanistic studies indicate that EDNRA activates phospholipase C, which then 1) increases the MMP1 protein levels through activation of the extracellular signal-regulated kinase mitogen-activated protein kinase-dependent pathway and 2) upregulates RANKL by a different pathway. CONCLUSION: These results suggest that EDNRA may function in the breakdown of the periodontal tissues associated with periodontitis by promoting the protein expression of MMPs and RANKL via the phospholipase C pathway.

Progress in Study on Endothelin-1 in Pathogenesis of Inflammatory Bowel Disease / 胃肠病学

Inflammatory bowel disease(IBD)is a kind of chronic and non-specific inflammatory disease comprising Crohn’s disease(CD)and ulcerative colitis(UC),the etiology has not yet been clarified. Endothelin-1(ET-1)is an active polypeptide composed of 21 amino acid residues,which can constrict blood vessels by activating voltage-dependent Ca2 + channels in vascular smooth muscle cells. Studies have shown that ET-1 plays an important role in the pathogenesis of IBD. This article reviewed the progress in study on ET-1 in the pathogenesis of IBD.

Anti-endothelin receptor type A autoantibody in lupus associated pulmonary arterial hypertension / 中华风湿病学杂志

Objective To investigate autoantibody against endothelin receptor type A (ENRA-Ab) in patients with systemic lupus erythematosus associated pulmonary arterial hypertension (SLE-PAH).The possibility of autoantibody-mediated pathogenesis in the development of SLE-PAH has also been explored.Methods ENRA-Ab in the serum of SLE-PAH and controls were detected by using a human ETRA epitope peptide-based ELISA.The clinical relevance of ENRA-Ab in SLE-PAH was analyzed.Proliferation of vascular smooth muscle cells (SMCs) and permeability of endothelial cells in vitro under the stimulation of polyclonal ENRA-Ab IgG were assessed.The expressions of PAH-related markers, i.e., 5-HTT, PDGFR-b, VEGF-A and PDGF-B were measured by qPCR.The effect of ENRA-Ab in vivo was also determined in a suboptimaldose monocrotaline-induced model with the assessment of right ventricle hypertrophy index and pathology parameters.Independent t-test, Tukey-Kramer test of variance analysis and Pearson' s correlation analysis were used for statistical analysis.Results ENRA-Abs was presented in a higher occurrence in SLE-PAH (35/85,41％) compared with controls (0/60;0, 13/80, 16％).There was a significant correlation between ENRA-Ab and echocardiograph estimated pulmonary arterial systolic pressure (r=0.392, P=0.002) in SLE-PAH.ENRA-Ab could promote SMCs proliferation, disrupt endothelial barrier and up-regulate PAH-related markers expression,which could be blocked in the presence of ETR antagonist.ENRA-Ab aggravated right ventricle hypertrophy and vascular remodeling in vivo.Conclusion ENRA-Ab is a new biomarker, in SLE-PAH, which may mediate PAH development in SLE.

Gestational hypoxia induces preeclampsia-like symptoms via heightened endothelin-1 signaling in pregnant rats.

Preeclampsia is a life-threatening pregnancy disorder. However, its pathogenesis remains unclear. We tested the hypothesis that gestational hypoxia induces preeclampsia-like symptoms via heightened endothelin-1 (ET-1) signaling. Time-dated pregnant and nonpregnant rats were divided into normoxic and hypoxic (10.5% O2 from the gestational day 6-21) groups. Chronic hypoxia had no significant effect on blood pressure or proteinuria in nonpregnant rats but significantly increased blood pressure on day 12 (systolic blood pressure, 111.7 ± 6.1 versus 138.5 ± 3.5 mm Hg; P=0.004) and day 20 (systolic blood pressure, 103.4 ± 4.6 versus 125.1 ± 6.1 mm Hg; P=0.02) in pregnant rats and urine protein (µg/µL)/creatinine (nmol/µL) ratio on day 20 (0.10 ± 0.01 versus 0.20 ± 0.04; P=0.04), as compared with the normoxic control group. This was accompanied with asymmetrical fetal growth restriction. Hypoxia resulted in impaired trophoblast invasion and uteroplacental vascular remodeling. In addition, plasma ET-1 levels, as well as the abundance of prepro-ET-1 mRNA, ET-1 type A receptor and angiotensin II type 1 receptor protein in the kidney and placenta were significantly increased in the chronic hypoxic group, as compared with the control animals. Treatment with the ET-1 type A receptor antagonist, BQ123, during the course of hypoxia exposure significantly attenuated the hypoxia-induced hypertension and other preeclampsia-like features. The results demonstrate that chronic hypoxia during gestation induces preeclamptic symptoms in pregnant rats via heightened ET-1 and ET-1 type A receptor-mediated signaling, providing a molecular mechanism linking gestational hypoxia and increased risk of preeclampsia.

The expressions of endothelin-1 and endothelin A/B receptors mRNA in tissue of benign prostatic hyperplasia treated by daily low-dose sildenafil / 中华老年医学杂志

Objective To observe the mRNA expressions of endothelin-1(ET-1) and endothelin A/B receptors (ETA/B) in tissue of benign prostatic hyperplasia treated by daily low-dose sildenafil.Methods A total of 32 patients with benign prostatic hyperplasia were randomly divided into two groups:treatment(25 mg sildenafi for 12 weeks,n=16) and control (no drug,n=16) groups.Immunohistochemical staining,ELISA and RT-PCR were used to detect the expression levels of ET-1 protein and ET A/B mRNA,respectively.Results The expressions of ET-1 protein and ET A/B mRNA in prostatic tissue were significantly lower in treatment group than in control group[(53.31±18.56) ng/kg vs.(83.34±31.38) ng/kg,0.356±0.056 vs.0.624±0.083,0.721±0.083 vs.0.933±0.905,t=-3.295,10.715,6.937,all P＜0.001].Conclusions Daily low-dose sildenafil can reduce the expressions of ET-1 and ET A/B receptors mRNA in benign prostatic hyperplasia.

The role of endothelin receptor A during myelination of developing oligodendrocytes.

Endothelin (ET)-1 and its receptors (ETA and ETB receptor) are present in the central nervous system. ET exerts biological effects on gliogenesis and glial cell functions. In order to define a possible mechanism of ETA receptor signaling, the distribution of the ETA receptor in developing oligodendrocytes and the effects of ET-1 on the myelination of oligodendrocytes were examined. ETA receptor immunoreactivity was confined to the perivascular elements of the blood vessels during early postnatal development. However later in development, ETA receptor immunoreactivity was no longer observed in the vessels but became localized to the myelinating oligodendrocytes of the primitive corpus callosum of the white matter, apart from the vessels. ET-1 induced myelin basic protein (MBP) in primary oligodendrocyte precursor cell culture though the ETA receptor and was blocked by an ETA receptor antagonist. In addition, ET-1 evoked the release of Ca(2+) which is a central regulator of oligodendrocyte differentiation. Our results provide a link between ET-1 and its ETA receptor and myelination during oligodendrocyte differentiation.

The Role of Endothelin Receptor A during Myelination of Developing Oligodendrocytes

Endothelin (ET)-1 and its receptors (ETA and ETB receptor) are present in the central nervous system. ET exerts biological effects on gliogenesis and glial cell functions. In order to define a possible mechanism of ETA receptor signaling, the distribution of the ETA receptor in developing oligodendrocytes and the effects of ET-1 on the myelination of oligodendrocytes were examined. ETA receptor immunoreactivity was confined to the perivascular elements of the blood vessels during early postnatal development. However later in development, ETA receptor immunoreactivity was no longer observed in the vessels but became localized to the myelinating oligodendrocytes of the primitive corpus callosum of the white matter, apart from the vessels. ET-1 induced myelin basic protein (MBP) in primary oligodendrocyte precursor cell culture though the ETA receptor and was blocked by an ETA receptor antagonist. In addition, ET-1 evoked the release of Ca2+ which is a central regulator of oligodendrocyte differentiation. Our results provide a link between ET-1 and its ETA receptor and myelination during oligodendrocyte differentiation.

Regulatory effect of endothelin on the expression of transformation growth factor-beta 1 and phosphorylated Smad 3 in A375 cells in vitro / 中华皮肤科杂志

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.

Effects of inhalation of endothelin-A receptor antagonist on experimental acute lung injury / 解放军医学杂志

0.05). CO decreased at T2, T3, T4 and T5 compared with that at T0 in both groups (P