Endothelin-1 mRNA Expression Research Articles

Cys-peptide mediates the protective role in preeclampsia-like rat and cell models

ObjectiveThe present study was designed to investigate whether the novel peptide cysteine-based peptide (Cys-peptide) had protective effects on preeclamptic animal and cell models. MethodsWe investigated effects of Cys-peptide on (1) preeclamptic symptoms (e.g. hypertension, proteinuria, fetal growth restriction (FGR)) in preeclampia-like rat models induced by lipopolysaccharides (LPS), (2) TNFα-induced cytotoxicity of human umbilical vascular endothelial cells (HUVECs) and HTR-8 cells (an immortalised human trophoblast cell line), (3) endothelial dysfunction and injured angiogenesis, (4) migration and invasion of trophoblast cells induced by TNFα. ResultsCys-peptide ameliorated LPS-induced hypertension, proteinuria and FGR and other PE symptoms in preeclampia-like rat models. In addition, Cys-peptide attenuated TNFα-induced cytotoxicity by decreasing soluble fms-like tyrosine kinase-1 (sFlt-1), endothelin-1 (ET-1) and tissue plasminogen activator (tPA) mRNA expression in both cells. Furthermore, Cys-peptide restored endothelial dysfunction and rescued angiogenesis caused by TNFα in vitro. Importantly, Cys-peptide could reverse insufficient ability to invade and migrate of trophoblast cells. ConclusionsThese results suggest Cys-peptide can play beneficial roles in preeclampsia-like rat and cell models. Therefore, we propose that Cys-peptide is probably a novel therapeutic candidate for PE.

Mandibular Advancement Devices Prevent the Adverse Cardiac Effects of Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS)

Although considerable research highlights the interactions between obstructive sleep apnea-hypopnea syndrome (OSAHS) and cardiovascular diseases, the effect of mandibular advancement device (MAD) treatment on cardiovascular complications in OSAHS patients remains unclear. We evaluated the effect of OSAHS treatment with MADs on the myocardium. All methods in this study were in accordance with relevant guidelines and regulations of the medical ethics committee in Hospital of Stomatology, Hebei Medical University approved the work. Thirty New Zealand rabbits were randomized into three groups: the control group, Group OSAHS, and Group MAD. Hydrophilic polyacrylamide gel was injected into the soft palate of the rabbits to induce OSAHS. In Group MAD, a MAD was positioned after OSAHS induction. All animals were induced to sleep in a supine position for 4–6 h/day for 8 weeks. Echocardiography was used to determine the structure and function of the heart. The histological changes were detected by optical microscopy and transmission electron microscopy (TEM). The levels of ET-1(endothelin-1) and Ang II (Angiotensin II) in the plasma were measured by an enzyme-linked immunosorbent assay (ELISA). The expression of ET-1 mRNA in heart tissue was detected by RT-PCR. Histological abnormalities, left ventricular hypertrophy, and left ventricular dysfunctions were demonstrated in Group OSAHS, and the abnormities were rescued with MAD treatment. Higher levels of plasma ET-1 and Ang II and elevated expression of ET-1 mRNA in cardiac tissue were detected in Group OSAHS compared with Group MAD and the control group. The blood oxygen saturation was negatively correlated with the levels of ET-1 and Ang II. OSAHS-induced elevated levels of ET-1 and Ang II may be attributed to myocardial structural abnormalities and dysfunction. Early treatment of MADs may play an important role in preventing myocardial damage in OSAHS rabbit model.

Liraglutide ameliorates palmitate-induced oxidative injury in islet microvascular endothelial cells through GLP-1 receptor/PKA and GTPCH1/eNOS signaling pathways

In type 2 diabetes, lipotoxicity damages islet microvascular endothelial cells (IMECs), leading to pancreatic islet β cell dysfunction directly or indirectly. Glucagon-like peptide-1 (GLP-1) and its analogs have beneficial roles in endothelial cells. However, the protective effects of GLP-1 agents on IMECs and their potential mechanism remained obscure. In this study, exposure of MS-1 (a cell line derived from mouse IMECs) to different concentrations of palmitic acid (PA) was used to establish an injury model. The cells exposed to PA (0.25 mmol/L) were treated with a GLP-1 analog liraglutide (3, 10, 30, and 100 nmol/L). Reactive oxygen species (ROS) generation, apoptosis-related protein level, and endothelin-1 production were detected. The protein levels of signaling molecules were analyzed and specific inhibitors or blockers were used to identify involvement of signaling pathways in the effects of liraglutide. Results showed that PA significantly increased ROS generation and the levels of pro-apoptotic protein Bax, and decreased the levels of anti-apoptotic protein Bcl-2 and the mRNA expression and secretion of endothelin-1. Meanwhile, PA downregulated the protein levels of GLP-1 receptor (GLP-1R), phosphorylated protein kinase A (PKA), guanosine 5′-triphosphate cyclohydrolase 1 (GTPCH1), and endothelial nitric oxide synthase (eNOS). Furthermore, liraglutide ameliorated all these effects of PA in a dose-dependent manner. Importantly, GLP-1R antagonist exendin (9–39), PKA inhibitor H89, GTPCH1 inhibitor 2,4-diamino-6-hydroxypyrimidine, or NOS inhibitor N-nitro-l-arginine-methyl ester abolished the liraglutide-mediated amelioration in PA-impaired MS-1 cells. In conclusion, liraglutide ameliorates the PA-induced oxidative stress, apoptosis, and endothelin-1 secretion dysfunction in mouse IMECs through GLP-1R/PKA and GTPCH1/eNOS signaling pathways.

Isolation and Characterization of Three Antihypertension Peptides from the Mycelia of Ganoderma Lucidum (Agaricomycetes).

Ganoderma lucidum (G. lucidum) has been widely used in Asia to treat hypertension, but the active substances responsible for its antihypertensive effects remain unclear. Using the well-established angiotensin I-converting enzyme (ACE) as a target, we identified three ACE inhibitory peptides (ACEIPs), Gln-Leu-Val-Pro (QLVP), Gln-Asp-Val-Leu (QDVL), and Gln-Leu-Asp-Leu (QLDL), which account for the antihypertensive activity of G. lucidum. Notably, QLVP worked in a mixed-type manner against ACE with an IC50 value of 127.9 μmol/L. Molecular dynamics simulation suggested that the potent charge energy of QLVP, which interacted with Gln242 and Lys472 of ACE via a hydrogen bond and a salt bridge, potentially contributed to ACE inhibitory activity. Moreover, QLVP markedly activated angiotensin I-mediated phosphorylation of endothelial nitric oxide synthase in human umbilical vein endothelial cells and partly reduced mRNA and protein expression of the vasoconstrictor factor endothelin-1. This is the first report of the antihypertensive activity of small ACEIPs originating from G. lucidum mycelia, paving the way for the possible application of these peptides as potent drug candidates for treating hypertension.

Chinese Medicine Shensong Yangxin Capsule () Ameliorates Myocardial Microcirculation Dysfunction in Rabbits with Chronic Myocardial Infarction.

To investigate the effect of Chinese compound Shensong Yangxin Capsule ( , SSYX) on myocardial microcirculation in myocardial-infarcted rabbits. Myocardial infarction (MI) was established in rabbits by ligation of the left circumflex coronary. Thirty rabbits were randomly divided into the control group, the MI group (model), and the MI treated with SSYX group (MI+SSYX) by a random number table method. After 4 weeks of administration, low-energy real-time myocardial contrast echocardiography (RT-MCE) was conducted to assess the microcirculatory perfusion. Immunofluorescence double staining was used to detect the capillary density. The endothelial ultrastructure was observed with a transmission electron microscope. The mRNA expression levels of vascular endothelial growth factor (VEGF), endothelin 1 (ET-1), prostaglandin I2 (PGI2) and endothelial nitric oxide synthase (eNOS) were measured by real-time quantitative polymerase chain reaction (Real-time PCR). The plasmic levels of ET-1, thromboxane A2 (TXA2), nitric oxide (NO) and von willebrand factor (vWF) were examined with enzyme-linked immunosorbent assays (ELISA). SSYX significantly improved the myocardial blood volume, myocardial micro bubble velocity, and myocardial inflow according to the examination of RT-MCE, and it visibly ameliorated the capillary endothelial structure. Furthermore, compared with the MI group, the plasma levels of TXA2, ET-1 and vWF contents significantly decreased in the MI+SSYX group, and the ET-1 mRNA expression levels of myocardium in the border zone significantly decreased, and the VEGF, PGI2 and eNOS mRNA expression levels significantly increased (all P<0.05). SSYX has favorable advantages in ameliorating the impaired myocardial microcirculation following MI. The mechanisms of the effect are related to the ability of SSYX in balancing the endothelial-derived vasodilators and vasoconstrictors, and up-regulating the expression of VEGF and eNOS.

(-)-Epigallocatechin-3-gallate protects against uric acid-induced endothelial dysfunction in human umbilical vein endothelial cells

Background: Hyperuricemia is recently reported to be associated with hypertension, metabolic syndrome, and vascular damage. (-)-Epigallocatechin gallate (EGCG) is a major polyphenol component of green tea involving in potent anti-inflammatory and antioxidant effects. The study assessed the effect of EGCG on uric acid (UA)-induced vascular damage. Materials and Methods: The cell viability and angiogenic formation of human umbilical vein endothelial cells (HUVECs) treated with UA and EGCG were determined by methylthiazol tetrazolium and tube formation assays, respectively. The expression level of inflammatory cytokine and vascular factor, including nuclear factor-kappa B (NF-κB), monocyte chemotactic protein-1 (MCP-1), intercellular adhesion molecule 1 (ICAM-1), cycloxygenase-2, tumor necrosis factor (TNF-α), induced nitric oxide synthetase (iNOS), endothelin-1 (ET-1), and von Willebrand factor, were examined by real-time quantitative reverse transcription polymerase chain reaction. The expression of P65 in HUVECs treated with UA in different time points or different concentrations was detected by Western blotting. Results: EGCG suppressed UA-inducing HUVEC cells death. UA treatment of HUVEC significantly increases the expression of P65. EGCG significantly inhibited the UA-induced mRNA expression of NF-κB, MCP-1, ICAM-1, TNF-α, iNOS, and ET-1 in HUVECs. Functional analysis of angiogenic inhibition showed that pretreatment with EGCG improved the vascular tube formation. Conclusion: Our results suggested that UA-induced inflammatory cytokine production and impaired endothelial cell function in HUVECs were attenuated by EGCG. These data indicated that EGCG has a therapeutic potential for UA-mediated endothelial damage.

Adipose-Derived Stem Cell Transplantation Inhibits Vascular Inflammatory Responses and Endothelial Dysfunction in Rats with Atherosclerosis.

PurposeThis study aimed to investigate the effect of adipose-derived stem cell (ADSC) transplantation on atherosclerosis (AS) and its underlying mechanisms.Materials and MethodsIn our study, rat AS model was established, and ADSCs were isolated and cultured. Atherosclerotic plaque and pathological symptoms of thoracic aorta were measured by Oil Red O staining and Hematoxylin-Eosin staining, respectively. Total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels were measured by an automatic biochemical analyzer. Expressions of vascular endothelial growth factor (VEGF), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), aortic endothelin-1 (ET-1), interleukin-6 (IL-6), c-reactive protein (CRP), and tumor necrosis factor α (TNF-α) were measured by enzyme linked immunosorbent assay, VEGF, VCAM-1, ICAM-1, ET-1, respectively, and NF-κB p65 mRNA expressions were detected by quantitative real-time polymerase chain reaction. Protein expressions of VEGF, VCAM-1, ICAM-1, ET-1, NF-κB p65, p-NF-κB p65, and IκBα were measured by western blot. Moreover, NF-κB p65 expression was measured by immunofluorescence staining.ResultsADSC transplantation alleviated the pathological symptoms of aortic AS. ADSC transplantation decreased the levels of TC, TG, and LDL-C and increased serum HDL-C level. Meanwhile, ADSC transplantation decreased the levels of IL-6, CRP, and TNF-α in AS rats. Moreover, the expressions of VEGF, ET-1, VCAM-1, and ICAM-1 were decreased by ADSC transplantation. ADSC transplantation inhibited phosphorylation of NF-κB p65 and promoted IκBα expression in AS rats.ConclusionOur study demonstrated that ADSC transplantation could inhibit vascular inflammatory responses and endothelial dysfunction by suppressing NF-κB pathway in AS rats.

Curcumin Inhibited Endothelin mRNA Expression Induced by TGF-β in Bovine Endothelial Cell

Objectives: Curcumin is a plant polyphenol compound used as a traditional supplement in many countries. The potential therapeutic or preventive effects of curcumin may be related to its antioxidant and anti-inflammatory properties. The current in vitro study aimed to investigate the effect of curcumin on the expression of endothelin-1 (ET-1) stimulated by transforming growth factorbeta (TGF-β) in bovine aortic endothelial cells (BAECs). Methods: Bovine aortic endothelial cells derived from bovine aorta were maintained in low glucose DMEM (Dulbecco’s modified Eagle’s medium). The time-course and different concentrations of TGF-β (2 ng/mL and 10 ng/mL) were used to evaluate ET-1 mRNA expression. Also, the BAECs were treated with 10 µM of SB431542 (chemical inhibitor of TGF-β receptor) as positive control and different doses of curcumin (5 µM, 10 µM, and 15 µM). The expression of ET-1 mRNA was quantified by quantitative real-time polymerase chain reaction (qPCR). Statistical analysis was performed by one-way ANOVA with SPSS software. Results: ET-1 mRNA expression significantly increased in six hours in the TGF-β-treated group (2.79 ± 0.9). SB431542, as well as curcumin 10 µM and 15 µM significantly decreased the expression of ET-1 mRNA by 2.3±0.15, 1.5±0.16, and 1.02±0.01, respectively. Conclusions: Curcumin downregulated ET-1 mRNA; this result suggested a possible underlying molecular mechanism mediated through ET-1 to exert its anti-inflammatory and antioxidant properties.

SUR2B/Kir6.1 channel openers correct endothelial dysfunction in chronic heart failure via the miR-1-3p/ET-1 pathway

The SUR2B/Kir6.1 channel openers iptakalim and natakalim reverse cardiac remodeling and ameliorate endothelial dysfunction by re-establishing the balance between the nitric oxide and endothelin systems. In this study, we investigated the microRNAs (miRs) involved in the molecular mechanisms of SUR2B/Kir6.1 channel opening in chronic heart failure. Both iptakalim and natakalim significantly upregulated the expression of miR-1-3p, suggesting that this miR is closely associated with the therapeutic effects against chronic heart failure. Bioinformatic analysis showed that many of the 183 target genes of miR-1-3p are involved in cardiovascular diseases, suggesting that miR-1-3p plays a vital role in such diseases and vascular remodeling. Target gene prediction showed that miR-1-3p combines with the 3′ untranslated region (UTR) of endothelin-1 (ET-1) mRNA. Iptakalim and natakalim upregulated miR-1-3p expression and downregulated ET-1 mRNA expression in vitro. The dual luciferase assay confirmed that there is a complementary binding sequence between miR-1-3p and the 3′ UTR 158–165 sequence of ET-1 mRNA. To verify the effect of miR-1-3p on ET-1, lentiviral vectors overexpressing or inhibiting miR-1-3p were constructed for the transduction of rat primary cardiac microvascular endothelial cells. The results showed that natakalim enhanced the miR-1-3p level. miR-1-3p overexpression downregulated the expression of ET-1, whereas miR-1-3p inhibition had the opposite effect. Therefore, we verified that SUR2B/Kir6.1 channel openers could correct endothelial imbalance and ameliorate chronic heart failure through the miR-1-3p/ET-1 pathway in endothelial cells. Our study provides comprehensive insights into the molecular mechanisms behind the SUR2B/Kir6.1 channel’s activity against chronic heart failure.

Placental CD4+ T cells isolated from preeclamptic women cause preeclampsia-like symptoms in pregnant nude-athymic rats.

Preeclampsia (PE), new onset hypertension during pregnancy, is associated with a proinflammatory profile compared to normal pregnancy (NP). We hypothesize that CD4+ T cells from PE patient placentas cause PE symptoms during pregnancy compared to those from NP women. CD4+ T cells were isolated from placentas of PE and NP women using anti-CD4 magnetic separation, cultured in TexMACS medium at 37 °C in 5% CO2, and injected intraperitoneally into nude-athymic rats on day 12 of gestation. On day 18, carotid catheters were implanted and on day 19, mean arterial pressure (MAP) was measured and blood and tissues were collected. MAP was 125 ± 2 mmHg in rats with NP CD4+ T cells but increased to 140 ± 4 mmHg in rats with PE CD4+ T cells. Significant differences in circulating cytokines tumor necrosis factor-alpha (TNF-α), interleukin-17 (IL-17) and soluble fms-like tyrosine kinase-1 (sFlt-1) were found with PE vs NP CD4+ T cells (TNF-α- PE = 167.4 pg/mL, NP = 79.4 pg/mL; IL-17-PE = 7.054 pg/mL, NP = 3.185 pg/mL; sFlt-1-PE = 90.7 pg/mL, NP = 58.2 pg/mL. In addition, renal cortical endothelin-1 (ET-1) mRNA expression increased 4.5 fold in rats with PE CD4+ T cells versus those receiving to NP CD4+ T cells. These data indicate an important role for placental PE CD4+ T cells to cause many characteristics of PE during pregnancy.

Abstract P149: VEGF Inhibitor-Induced Hypertension and Renal Injury: Prevention by Aspirin?

Vascular endothelial growth factor inhibitor (VEGFi)-induced hypertension and renal injury in cancer patients mimic the clinical phenotype of preeclampsia. ET-1 has been implicated to be involved. Since aspirin can prevent the onset of preeclampsia, we hypothesized that co-treatment of the VEGFi sunitinib (SU) with aspirin might be beneficial and may improve ET-1 status. Male WKY rats were treated with vehicle, 14 mg/kg/day SU, or SU + low or high dose aspirin (5 or 100 mg/kg/day) for 8 days. Mean arterial pressure (MAP) was measured via radiotelemetry. On day 8, 24h urine was collected to determine albuminuria and prostanoid (PGF2α and TxB2) levels. Plasma endothelin-1 (ET-1) was measured via ELISA. Endothelial dysfunction was assessed in iliac vessels and reactive oxygen species (ROS) was measured via aortic superoxide anion production. Renal cyclooxygenase (COX)-1, COX-2 and ET-1 mRNA expression were determined via PCR. SU induced a rapid and sustained increase in MAP (24±2 versus 1±1 mmHg in vehicle on day 6; P&lt;0.001), which was blunted by both low and high aspirin doses (18±3 and 13±4 mmHg respectively on day 6; P&lt;0.05 versus SU). Plasma ET-1 was increased by SU (2.2±0.3 versus 1.4±0.1 pg/ml in vehicle; P&lt;0.05) and this was not affected by aspirin. SU increased albuminuria (1.2±0.2 versus 0.3±0.1 mg/24h in vehicle; P&lt;0.05) which was prevented by high, but not low dose aspirin (0.5±0.1 and 1.3±0.1 mg/24h, respectively), suggesting that this effect is COX-2 dependent. Although renal mRNA expression levels were unchanged, renal COX-2 and ET-1 mRNA expression correlated positively, suggesting that ET-1 upregulates COX-2. SU increased ROS production 2.5-fold (P&lt;0.05 versus vehicle) and this was prevented by both aspirin doses. SU did not induce endothelial dysfunction, nor did it alter prostanoid levels. However, both aspirin doses reduced TxB2 (P&lt;0.05 versus vehicle). In conclusion, high rather than low dose aspirin was more efficacious for the prevention of VEGFi-induced hypertension and renal injury, suggesting that its beneficial effects largely involve COX-2 inhibition. Aspirin may be a novel intervention to allow cancer patients to gain the full benefit of VEGFi without deleterious cardiovascular and renal side effects.

Palmitic Acid Increases Endothelin-1 Expression in Vascular Endothelial Cells through the Induction of Endoplasmic Reticulum Stress and Protein Kinase C Signaling

Objective: We investigated the regulation of endothelin-1 (ET-1) expression in in vivo high-fat diet (HFD)-fed mice and in vitro cultured human aortic endothelial cells (HAECs). Methods: Male C57BL/6 mice were fed on standard chow, serum was prepared, and ET-1 levels were analyzed using an ELISA kit. Quantitative PCR was performed using iQ SYBR Green Supermix. Statistical significance was assessed using SPSS, with p < 0.05 considered significant. Results: The serum ET-1 content and endothelial expression of ET-1 mRNA were increased in the HFD-fed mice compared to the chow-fed control mice. Moreover, the mRNA expression of ET-1 was significantly increased in cultured HAECs in response to acute (< 24 h) and chronic (12–16 days) treatments with palmitic acid (PA), one of the most abundant saturated fatty acids in obesity. We found that the induction of ET-1 expression by PA was abolished by pretreating the cells with the endoplasmic reticulum (ER) stress inhibitor 4-phenylbutyric acid or the protein kinase C (PKC) inhibitor Gö 6850. Conclusion: Our findings demonstrate for the first time that PA increases ET-1 expression in endothelial cells through the induction of ER stress and the activation of PKC, providing novel mechanistic insights into the pathogenesis of obesity-associated hypertension and cardiovascular diseases.

Vitamin D upregulates endothelin-1, ETBR, eNOS mRNA expression and attenuates vascular remodelling and ischemia in kidney fibrosis model in mice.

We examined the upregulation of ET-1/ETBR/eNOS signaling in renoprotective effect of vitamin D in kidney fibrosis model in mice using unilateral ureteral obstruction (UUO). One group was treated with intraperitoneal injection of 0.125 mg/kg of Calcitriol (UUO+VD). Vascular remodeling was quantified based on lumen area and lumen/wall area ratio (LWAR) of intrarenal arteries using Sirius Red staining. ET-1, ETBR, eNOS, CD31 and VEGF mRNA expressions were quantified using qRT-PCR. Focusing on endothelin-1 (ET-1) signaling in endothelial cells (EC), siRNA of ET-1 was performed in human umbilical vein endothelial cells (HUVEC) for reducing ET-1 expression. Then HUVECs were treated with and without 100 nM Calcitriol treatment in hypoxic and normoxic conditions to elucidate ET-1/eNOS signaling. Our in vivo study revealed vascular remodeling and renal ischemia attenuation after Calcitriol treatment. Vascular remodeling was attenuated in the UUO+VD group as shown by increasing lumen areas and LWAR in intrarenal arteries. These findings were associated with significant higher CD31 and VEGF mRNA expression compared to the UUO group. Vitamin D treatment also increased ET-1, ETBR and eNOS mRNA expressions. Our in vitro study demonstrated Calcitriol induced ET-1 and eNOS mRNA expressions upregulation in HUVEC under normoxic and hypoxic condition. Meanwhile, siRNA for ET-1 inhibited the upregulation of eNOS mRNA expression after Calcitriol treatment. Vitamin D ameliorates kidney fibrosis through attenuating vascular remodeling and ischemia with upregulating ET-1/ETBR and eNOS expression.

Endothelin-1 regulation is entangled in a complex web of epigenetic mechanisms in diabetes.

Endothelial cells (ECs) are primary targets of glucose-induced tissue damage. As a result of hyperglycemia, endothelin-1 (ET-1) is upregulated in organs affected by chronic diabetic complications. The objective of the present study was to identify novel transcriptional mechanisms that influence ET-1 regulation in diabetes. We carried out the investigation in microvascular ECs using multiple approaches. ECs were incubated with 5 mM glucose (NG) or 25 mM glucose (HG) and analyses for DNA methylation, histone methylation, or long non-coding RNA- mediated regulation of ET-1 mRNA were then performed. DNA methylation array analyses demonstrated the presence of hypomethylation in the proximal promoter and 5' UTR/first exon regions of EDN1 following HG culture. Further, globally blocking DNA methylation or histone methylation significantly increased ET-1 mRNA expressions in both NG and HG-treated HRECs. While, knocking down the pathogenetic lncRNAs ANRIL, MALAT1, and ZFAS1 subsequently prevented the glucose-induced upregulation of ET-1 transcripts. Based on our past and present findings, we present a novel paradigm that reveals a complex web of epigenetic mechanisms regulating glucose-induced transcription of ET-1. Improving our understanding of such processes may lead to better targeted therapies.

Induction of ET‐1‐ and non‐ET‐1‐mediated endothelium‐dependent vasoconstriction in endotoxemic hypotensive shock

Effective managements of refractory hypotension to vasoconstrictors in severe sepsis are limited. A new strategy to ameliorate endotoxemic hypotension by inducing endothelium‐dependent constriction of endotoxemic large arteries was examined. In lipopolysaccharide (LPS)‐induced endotoxemic rats, oroxylin‐A (OroA, 15 mg/kg, iv) administered 6 hours after LPS‐challenge promptly reversed/normalized diminished mean arterial pressure and heart rate. OroA (1–10 μM), which did not constrict isolated normal arteries, repeatedly induced exclusive endothelium‐dependent sustained‐constriction without tachyphylaxis of isolated endotoxemic aortic and tail arteries. OroA‐induced constriction of mesenteric arteries with intact‐endothelium (EC+) was blocked by endothelin‐1 (ET‐1)‐receptor antagonists which, did not affect that of tail or aortic arteries, suggesting ET‐1‐mediated and non‐ET‐1‐substance(s)‐mediated vasoconstrictions, respectively. In parallel, repeated applications of ET‐1 to mesenteric arteries lead to significant tachyphylaxis, OroA, however, induced repeated constriction of tail arteries without tachyphylaxis, Moreover, OroA significantly decreased LPS‐induced expression of ET‐1 mRNA and proteins in tail arteries, while OroA increased those in the mesenteric arteries, suggesting the heterogeneities of the endothelial cells. OroA‐induced ET‐1‐mediated and non‐ET‐1‐substance(s)‐mediated constrictions of all isolated arteries (EC+) were blocked exclusively by ROCK inhibitors. OroA reversed LPS‐induced suppression of RhoA‐activities and enhanced ROCK‐phosphorylation only in arteries with endothelium. Activated muscle ROCK‐activities in mesenteric arteries (EC+) but not those in tail or aortic arteries (EC+) were blocked by ET‐1‐receptor antagonists. Moreover, OroA‐post‐treatment suppressed, via inhibiting NF‐κB, inducible‐NOS expression and circulating NO. LPS induces region‐dependent expression of endothelial ET‐1‐ and/or non‐ET‐1‐vasoconstrictors. Both ET‐1 and non‐ET‐1 were released specifically by OroA‐activated muscle RhoA/ROCK‐pathway, causing prompt‐and‐sustained vasoconstriction that partly is due to OroA‐induced decrease of circulating NO. Simultaneous preservation of endothelial functions, induction of endothelium‐dependent constriction of large arteries, and suppression of systemic inflammation, as shown by OroA, offer new strategies for acute management of endotoxemic‐hypotensive shock.Support or Funding Informationsupported by MOST &amp; Tzu Chi FoundationThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Oleanolic Acid, a Novel Endothelin A Receptor Antagonist, Alleviated High Glucose-Induced Cardiomyocytes Injury.

Endothelin-1 (ET-1) and its receptor endothelin A receptor (ET[Formula: see text] have been shown to be upregulated in a high glucose environment, which increase the incidence of diabetes-related heart failure. Our previous study demonstrated that oleanolic acid (OA), a natural compound found in Chinese herbs had ET-1 antagonistic effects. We aimed to verify whether OA could ameliorate diabetes mellitus (DM)-induced injury in cardiomyocytes by reducing the antagonistic effects of the ET-1 pathway. For the induction of high glucose-related injury in cardiomyocytes, neonatal rat ventricular cardiomyocytes (NRVMs) were subjected to culture medium containing 25[Formula: see text]mM of glucose. Natriuretic peptide B (BNP), mitochondrial membrane potential (MMP) and cell surface area were measured to evaluate the severity of NRVMs injury. mRNA expression of ET-1 and ETA was determined using quantitative PCR. Moreover, a Ca[Formula: see text] influx assay was used to evaluate potential ETA antagonistic effects. Molecular docking of OA and ETA was performed using the Sulflex-Dock program. Human induced pluripotent stem cell (iPS-C)-derived cardiomyocytes and real time cell analysis system (RTCA) were used to verify the effect of OA on the ET-1 pathway. High glucose levels increased the expression of BNP at both mRNA and protein levels in cardiomyocytes. Moreover, cell surface area and MMP were also elevated in a high glucose environment. High glucose-induced injury in NRVMs was not reversible by hypoglycemic therapy. In addition, ETA was upregulated by high glucose treatment and levels could not be reduced by hypoglycemic treatment. The Ca[Formula: see text] influx assay on ETA/HEK293 cells showed that OA had a partial ETA antagonistic effect. Molecular docking approaches showed that OA was docked into the active site of ETA. Furthermore, functionality tests based on iPS-C and RTCA demonstrated that treatment with OA could reverse ET-1-induced alternation of beating rates and amplitude. Thus, OA could reverse high glucose-induced BNP upregulation, and increased both the cell area and MMP in NRVMs. High glucose-induced irreversible ETA upregulation is a major reason of continuous diabetes-related injury in cardiomyocytes. Treatment with OA had a protective effect on high glucose-induced injury in cardiomyocytes through a partial ETA antagonistic role.

CARDIOPROTECTIVE EFFECTS OF CURCUMIN AGAINST DIABETES AND NICOTINE-COMBINED OXIDATIVE STRESS

Background: Diabetic cardiomyopathy (DCM) develop through oxidative stress-induced myocardial cell apoptosis that cause cardiac tissue damage resulting in hemodynamics disturbance while Cigarette Smoking (CS) is associated with a significant increase in the risk of recurrent ventricular tachyarrhythmia in ischemic and non-ischemic cardiomyopathy patients caused by oxidative stress. Curcuma longa extract (curcumin) is known to protect against hyperglycemia-induced oxidative stress. This brought in mind to investigate the probability of the crcumin ability to ameliorate the combined diabetes and smoking induced oxidative stress caused DCM&#x0D; Materials and Methods: Diabetic rats were administered nicotine to investigate the effect of the combined oxidative stress of diabetes and nicotine. Moreover, curcumin was administered to examine its protective effect on possible oxidative stress induced diabetes and nicotine.&#x0D; Results: Nicotine administration in a dose of 1.5 mg/kg to diabetic rats increased the oxidative stress. This occurs through elevation of plasma nitric oxide (NO) and upregulation of cardiac tissue inducible nitric oxide synthase (iNOS) and Endothelin-1 mRNA expressions, in addition to elevation of plasma triglycerides (TG), and LDL and reduction of HDL levels. Nicotine administration also reduced the cardiac tissue protective mechanism through reduction of plasma superoxide dismutase (SOD), cardiac tissue Erythropoietin (EPO), vascular endothelial growth factor (VEGF) isoforms and VEGF receptor mRNA expressions. These combined oxidative stresses were manifested by elevation of the plasma cardiac markers troponin I and creatine kinase (CK-MB). Supplementation of curcumin prevented the diabetic and nicotine-induced oxidative stress through reduction of plasma NO and iNOS and Endothelin-1 mRNA expressions to their control levels and elevation of plasma SOD and upregulation of cardiac tissue Erythropoietin (EPO), vascular endothelial growth factor (VEGF) isoforms and VEGF receptor mRNA expressions. This curcumin protective effect of the cardiac tissue was manifested by normalization of the plasma cardiac marker troponin I and CK-MB.&#x0D; Conclusion: These results strongly confirmed that curcumin protected cardiac tissues from the combined oxidative stress induced by diabetes and nicotine.

Proton Pump Inhibitors Quench the Pathophysiological Characteristics of Preeclampsia in Both Human and Mouse Models and Represent an Exciting Novel Candidate Therapeutic

The antiangiogenic factors soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sENG) are elevated in preeclampsia and have been implicated in its pathogenesis. We have previously demonstrated metformin and sulfasalazine independently reduce antiangiogenic factor secretion. Here we examined whether combining metformin and sulfasalazine may be more effective than either alone in reducing placental expression and secretion of antiangiogenic and angiogenic factors and the expression of markers of endothelial dysfunction.We performed functional experiments using primary human placenta to explore the effect of metformin and sulfasalazine, at lower doses than previously explored, individually and in combination, on sFlt-1 and sENG secretion and placental growth factor (PlGF) and vascular endothelial growth factor (VEGFα) expression. Using primary endothelial cells we induced dysfunction using cytokine tumor necrosis factor-α (TNF-α) and assessed the effect of low dose combination treatment on the expression of vascular cell adhesion molecule-1 (VCAM-1) and Endothelin-1 (a potent vasoconstrictor).We demonstrated combination metformin and sulfasalazine was additive in reducing sFlt-1 secretion from cytotrophoblasts and placental explants. Combination treatment was also additive in reducing sENG secretion from placental explants. Furthermore, combination treatment increased cytotrophoblast VEGFα mRNA expression. Whilst combination treatment increased PlGF mRNA expression this was similar to treatment with sulfasalazine alone. Combination therapy reduced TNFα induced endothelin-1 mRNA expression however did not change VCAM expression.Low dose combination metformin and sulfasalazine reduced cytotrophoblast sFlt-1 and sENG secretion, increased VEGFα expression and reduced TNFα induced endothelin-1 expression in primary endothelial cells. Combination therapy has potential to treat preeclampsia.

Bradykinin system is involved in endometriosis-related pain through endothelin-1 production.

Endometriosis is a gynaecological disease exhibiting severe pelvic pain, but the mechanism of pain production remains unknown. Bradykinin (BK) is known as an inflammatory mediator, and shows elevated levels in inflammatory diseases such as rheumatoid arthritis. In the present study, we evaluated whether BK is involved in endometriosis-related pain. Endometriotic lesions were used for immunohistochemistry. Primary cultures of endometriotic stromal cells (ESC) were stimulated with IL-1β and/or BK. Quantitative RT-PCR was used to evaluate the mRNA expressions of BK receptors (BKR) and endothelin-1 in ESC. The concentration of endothelin-1 in cystic fluid of endometrioma or non-endometrioma was measured with ELISA. The conditioned medium of ESC stimulated with IL-1β and/or BK was injected intraplantarly in mice, and evaluated whether pain-related licking behaviour was elicited. The expressions of BK and BKR in endometriotic lesions were observed by immunohistochemistry. In vitro experiments showed that IL-1β induced BKR-B1 and B2 on ESC. Activation of these receptors by BK significantly induced endothelin-1 expression in ESC, which was negated completely by HOE-140, a BKR-B2 antagonist. The cystic fluid of endometrioma contained higher amount of endothelin-1 compared to non-endometrioma. Intraplantar injection of the conditioned medium of ESC treated with IL-1β and BK significantly induced licking behaviour, which was suppressed with BQ-123, an endothelin type-A receptor antagonist. The present study demonstrated the presence and the function of the BK axis in endometriosis, and established a potential new therapy target for endometriosis-related pain. The present study demonstrated (1) the presence and the function of the BK system in endometriosis, (2) activation of BKR induced endothelin-1 in endometriotic lesion and (3) blocking endothelin-1 was effective to decrease pain.

Sulfatase 1 mediates the inhibitory effect of angiotensin II type 2 receptor inhibitor on angiotensin II-induced hypertensive mediator expression and proliferation in vascular smooth muscle cells from spontaneously hypertensive rats

Background: Extracellular sulfatases (Sulfs), sulfatase 1 (Sulf1) and sulfatase 2 (Sulf2), play a pivotal role in cell signaling by remodeling the 6-O-sulfation of heparan sulfate proteoglycans on the cell surface. The present study examined the effects of Sulfs on angiotensin II (Ang II)-induced hypertensive mediator expre-ssion and vascular smooth muscle cells (VSMCs) proliferation in spontaneously hypertensive rats (SHR). Methods: Ang II receptors, 12-lipoxygenase (12-LO), and endothelin-1 (ET-1) messenger RNA (mRNA) ex-pressions in SHR VSMCs were analyzed by real-time polymerase chain reaction and Western blotting. VSMCs proliferation was determined by [ 3 H]-thymidine incorporation. Results: Basal Sulfs mRNAs expression and enzyme activity were elevated in SHR VSMCs. However, Sulfs had no effect on the basal or Ang II-induced 12-LO and ET-1 mRNA expression in SHR VSMCs. The inhibition of Ang II-induced 12-LO and ET-1 expression by blockade of the Ang II type 2 receptor (AT 2 R) pathway was not observed in Sulf1 siRNA-transfected SHR VSMCs. However, Sulf2 did not affect the action of AT 2 R inhibitor on Ang II-induced 12-LO and ET-1 expression in SHR VSMCs. The down-regulation of Sulf1 induced a reduction of AT 2 R mRNA expression in SHR VSMCs. In addition, the inhibition of Ang II-induced VSMCs proliferation by blockade of the AT 2 R pathway was mediated by Sulf1 in SHR VSMCs. Conclusion: These findings suggest that extracellular sulfatase Sulf1 plays a modulatory role in the AT 2 R pathway that leads to an Ang II-induced hypertensive effects in SHR VSMCs.