endothelin-1 and nitrofen

Congenital diaphragmatic hernia (CDH) leads to pathophysiologic pulmonary vasoreactivity. Previous studies show that mesenchymal stromal cell-derived extracellular vesicles (MSCEv) inhibit lung inflammation and vascular remodeling. We characterize MSCEv and human pulmonary artery endothelial cell (HPAEC) interaction, as well as the pulmonary artery (PA) response to MSCEv treatment. HPAECs were cultured with and without exposure to nitrofen (2,4-dichloro-phenyl-p-nitrophenylether) and treated with MSCEv. HPAEC viability, architecture, production of reactive oxygen species (ROS), endothelial dysfunction-associated protein levels (PPARγ, LOX-1, LOX-2, nuclear factor-κB [NF-κB], endothelial NO synthase [eNOS], ET-1 [endothelin 1]), and the nature of MSCEv-cellular interaction were assessed. Newborn rodents with and without CDH (nitrofen model and Sprague-Dawley) were treated with intravascular MSCEv or vehicle control, and their PAs were isolated. Contractility was assessed by wire myography. The contractile (KCL and ET-1) and relaxation (fasudil) responses were evaluated. HPAEC viability correlated inversely with nitrofen dose, while architectural compromise was directly proportional. There was a 2.1 × increase in ROS levels in nitrofen HPAECs (

Topics: Adult; Animals; Cell Death; Clathrin; Endocytosis; Endothelial Cells; Endothelin-1; Endothelium; Extracellular Vesicles; Female; Fluorescent Dyes; Hernias, Diaphragmatic, Congenital; Humans; NF-kappa B; Phenyl Ethers; Pulmonary Artery; Rats, Sprague-Dawley; Reactive Oxygen Species; Scavenger Receptors, Class E; Vasoconstriction

In congenital diaphragmatic hernia (CDH), pulmonary hypertension increases right ventricle (RV) afterload, which could impair heart function and contribute to poor outcome for most affected infants. Nevertheless, the real significance of vascular pulmonary alterations in perinatal hemodynamics is largely unknown. It is defined that ventricular pressure overload induces increased myocardium gene expression of B-type natriuretic peptide (BNP) and components of the renin-angiotensinogen and endothelin (ET)-1 systems. Our aim was to evaluate perinatal myocardium expression of these genes associated with ventricular pressure overload in a nitrofen-induced CDH rat model.. In the nitrofen-induced CDH rat model, fetuses from dated pregnant Sprague-Dawley rats at 15.5, 17.5, 19.5 and 21.5 days postcoitum as well as newborn pups were assigned to 3 experimental groups: control, nitrofen (exposed to nitrofen, without CDH), and CDH (exposed to nitrofen, with CDH). Myocardial samples collected from the RV and left ventricle (LV) were processed for quantification of messenger RNA (mRNA) of BNP, angiotensinogen, and ET-1.. The perinatal expression of BNP, angiotensinogen, and ET-1 mRNA in the RV and LV of the control group revealed daily changes. During gestation, the expression of BNP and angiotensinogen mRNA underwent significant oscillation compared with control in both nitrofen-exposed fetuses, although we cannot identify significant differences between the nitrofen and CDH groups. After birth, we found a significant increasing expression of all studied genes only in the RV of CDH pups.. Perinatal myocardial quantification of BNP, angiotensinogen, and ET-1 mRNA levels suggests that both nitrofen-exposed and control pups revealed prenatal variations of expression of the studied genes. Moreover, CDH is associated with significant molecular alterations only in the RV after birth.

Topics: Adaptation, Biological; Angiotensinogen; Animals; Base Sequence; Biomarkers; Endothelin-1; Gene Expression; Genetic Markers; Heart Ventricles; Hernia, Diaphragmatic; Hernias, Diaphragmatic, Congenital; Hypertension, Pulmonary; Molecular Sequence Data; Myocardium; Natriuretic Peptide, Brain; Phenyl Ethers; Rats; Rats, Sprague-Dawley; RNA, Messenger

The aim of this study was to evaluate the effect of the traditional Chinese medicine tetrandrine (Tet) and to determine its possible mechanism on expression of endothelin-1 (ET-1) and epidermal growth factor (EGF) in the lung of a rat model of nitrofen-induced congenital diaphragmatic hernia (CDH).. A single oral dose (115 mg/kg) of nitrofen on day 9.5 of pregnancy was maternally administered to induce CDH. Pregnant rats were divided into 4 groups on day 18.5: control (n = 5), CDH (n = 5), CDH+dexamethasone (Dex) (n = 5), and CDH+Tet (n = 5). All fetuses were delivered by cesarean delivery on day 21.5. Accordingly, there were 4 groups of fetuses: control (n = 38), CDH (n = 25), CDH+Dex (n = 21), and CDH+Tet (n = 22). Lung tissue weight (LW) and body weight (BW) of each fetus were recorded, lung histologic evaluations and ET-1 and EGF immunohistochemistry staining were performed, and image analysis was performed after lung processing.. Five female rats in the control group produced 38 fetuses without CDH. CDH was observed in 68 of the 128 rat fetuses (53.1%) among the other 3 groups. The LW/BW ratio of the CDH group was significantly lower than those of the Dex and EGF groups (P < .05). The lungs of fetuses with CDH showed marked abnormal structure such as pulmonary hypoplasia and vascular remodeling, in contrast to improved pulmonary structure in lungs of fetuses in the CDH+Dex and CDH+Tet groups. Statistical differences in morphologic parameters (radial alveolar counts, percentage of alveoli, percentage of medial wall thickness, and vascular volume) were found (P < .05). The immunoreactivity of EGF and ET-1 in the CDH group was markedly stronger than that in the control, CDH+Dex, and CDH+Tet groups (P < .01). In addition, EGF and ET-1 expression in the CDH+Dex and CDH+Tet groups was stronger than that in the control group (P < .05). There was no difference in lung EGF and ET-1 immunoreactivity between CDH+Dex and CDH+Tet groups (P > .05).. Antenatal treatment with Tet may improve lung growth and vascular remodeling, and its mechanism seems to be involved in decreasing EGF and ET-1 expression. Tet administered maternally may be a hopeful new therapeutic option in the treatment of CDH and may be effective in helping to avoid the side effects of Dex.

Topics: Abnormalities, Drug-Induced; Alkaloids; Animals; Benzylisoquinolines; Birth Weight; Dexamethasone; Drug Evaluation, Preclinical; Drugs, Chinese Herbal; Endothelin-1; Epidermal Growth Factor; Female; Fetal Organ Maturity; Hernia, Diaphragmatic; Lung; Organ Size; Phenyl Ethers; Pregnancy; Pulmonary Artery; Random Allocation; Rats; Rats, Sprague-Dawley

The high mortality in patients with congenital diaphragmatic hernia (CDH) has been attributed to pulmonary hypoplasia and persistent pulmonary hypertension (PPH). Endothelin-1 (ET-1), nitric oxide (NO), and calcitonin gene-related peptide (CGRP) have been reported to be important vasoactive mediators in the perinatal pulmonary circulation. The exact mechanism by which these vasoactive mediators interact to regulate the perinatal pulmonary vascular tone in CDH with PPH is not fully understood. We hypothesized that the altered pulmonary vascular reactivity in CDH is due to imbalance in vasoactive mediators. This study was designed to investigate mRNA expression of ET-1, eNOS, and CGRP in CDH lung in the perinatal period. A CDH model was induced in pregnant rats following administration of nitrofen. In control animals, the same dose of olive oil was given without nitrofen. Cesarean section was performed on day 21 of gestation. The newborn rats were intubated and ventilated, and ventilation was continued for 1-6 h. Left lungs were collected from both groups at 0, 1, and 6 h after ventilation (n=8 in each group). Reverse transcriptase-polymerase chain reaction on lung tissue was performed to evaluate the relative level of ET-1, eNOS, and CGRP mRNA expression. The results showed a significant increase in ET-1 mRNA in CDH lung at 1 and 6 h after ventilation compared with controls. In CDH lung, eNOS mRNA and CGRP mRNA levels were significantly increased at 1 h but were similar to control values at 6 h after ventilation. The increased expression of vasoconstrictor ET-1 mRNA and vasodilators eNOS mRNA and CGRP mRNA in the CDH lung at 1 h after ventilation suggests that pulmonary vascular tone is rapidly changing after birth. An imbalance in the production of vasoconstrictors and vasodilators by the CDH lung may contribute to high pulmonary vascular resistance.

Topics: Animals; Animals, Newborn; Calcitonin Gene-Related Peptide; Disease Models, Animal; Endothelin-1; Female; Gene Expression Regulation, Developmental; Herbicides; Hernia, Diaphragmatic; Lung; Maternal Exposure; Nitric Oxide Synthase; Nitric Oxide Synthase Type III; Phenyl Ethers; Pregnancy; Prenatal Exposure Delayed Effects; Pulmonary Circulation; Random Allocation; Rats; Rats, Sprague-Dawley; Respiration, Artificial; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Vascular Resistance; Vasoconstriction; Vasodilation

Although high levels of endothelin-1 (ET-1) in plasma may be relevant in certain pathophysiologic states, such as pulmonary hypertension accompanying congenital diaphragmatic hernia (CDH), experimental evidence favors a local, paracrine, or autocrine role for ET-1 in most tissues. Evidence of ET-1 production has been documented in fetal heart tissue where it exerts growth-enhancing and mitogenic effects. ET-1 also has a potent positive inotrope action on cardiac muscle. ET-1 -/- homozygous mice display a wide variety of cardiac anomalies, which also are features of the human and of the experimental CDH. Autopsy reports have shown that total heart weight is reduced significantly in the presence of CDH, and animal models have documented the presence of cardiac hypoplasia associated with CDH. Experimental and clinical studies have shown that prenatal exposure to corticosteroids improves cardiovascular function in the immediate newborn period. The aim of this study was to determine cardiac gene expression of ET-1 and of its receptor ET(A) and the cardiac ET-1 content in the heart of nitrofen-induced CDH in rats and to evaluate the effect of antenatal Dexamethasone (Dex) treatment.. A CDH model was induced in pregnant rats after administration of 100 mg of nitrofen on day 9.5 of gestation (term, 22 days). Dex (0.25 mg/kg) was given by intraperitoneal injection on days 18.5 and 19.5 of gestation. Cesarean section was performed on day 21 of gestation. The fetuses were divided into 3 groups: group I, control (n = 8); group II, nitrofen-induced CDH (n = 8); group III, nitrofen-induced CDH with antenatal Dex treatment (n = 8). ET-1 protein was measured using ELISA. RT-PCR was performed to evaluate the relative amount of ET-1 and ET(A) mRNA expression.. There was a reduction in ET-1 mRNA (P <.05) and in ET(A) mRNA (P <.01) in the heart of CDH group compared with controls. ET-1 protein level also was reduced in heart of CDH compared with controls. Antenatal Dex treatment increased significantly both ET-1 mRNA and protein levels in the heart of CDH animals (P <.05 and P <.01, respectively).. The reduced cardiac ET-1 gene expression and ET-1 synthesis may be responsible for the heart hypoplasia associated with CDH. Prenatal corticosteroids increase the cardiac production of ET-1, and this may enhance heart growth and cardiac inotropism at birth.

Topics: Animals; Base Sequence; Dexamethasone; Endothelin-1; Enzyme-Linked Immunosorbent Assay; Female; Gene Expression; Glucocorticoids; Hernia, Diaphragmatic; Myocardial Contraction; Myocardium; Phenyl Ethers; Pregnancy; Prenatal Exposure Delayed Effects; Rats; Rats, Sprague-Dawley; Receptors, Endothelin; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Stimulation, Chemical

The hypoplastic lung and persistent pulmonary hypertension (PPH) are the principle causes of high mortality and morbidity in infants with congenital diaphragmatic hernia (CDH). Endothelin-1 (ET-1), which is produced by vascular endothelial cells and some leukocytes, plays a key role in modulating pulmonary vascular tone in PPH. Two different receptors (ET(A) and ET(B)) for ET-1 have been characterized. Binding of ET-1 to ET(A), which is present on smooth muscle cells in fetal lung, results in vasoconstriction. However, binding of ET-1 to ET(B), which is present on endothelial cells results in vasodilation mediated by endogenous nitric oxide. Antenatal glucocorticoid therapy has been shown to prevent abnormal pulmonary arterial structural changes in animal model with CDH. The aim of this study was to investigate the effect of antenatal glucocorticoid administration on ET-1 system in nitrofen-induced CDH hypoplastic lung in rats.. A CDH model was induced in pregnant rats after administration of nitrofen on day 9.5 of gestation. Dexamethasone (Dex) was given intraperitoneally on days 18.5 and 19.5 of gestation. Cesarean section was performed on day 21 of gestation. Rat ET-1 protein expression was measured in solubilized lung tissue extracts, by sandwich type enzyme-linked immunosorbent assay (ELISA) analysis. Reverse transcription polymerase chain reaction was performed to evaluate the relative amount of ET-1, ET(A), and ET(B) mRNA expression.. The ET-1 protein and mRNA expression of ET-1 and both receptors were increased significantly in CDH lung compared with controls. Although there was no significant difference in ET(A) mRNA expression between CDH lung with Dex treatment and without Dex treatment, ET(B) mRNA expression was elevated significantly in CDH lung with Dex treatment compared with CDH lung without Dex treatment.. These findings suggest that antenatal glucocorticoid therapy may modulate pulmonary vascular tone in CDH hypoplastic lung by selectively upregulating local expression of ET(B).

Topics: Animals; Dexamethasone; Disease Models, Animal; Endothelin-1; Female; Glucocorticoids; Herbicides; Hernia, Diaphragmatic; Hypertension, Pulmonary; Phenyl Ethers; Pregnancy; Rats; Rats, Sprague-Dawley; Receptors, Endothelin; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

Pulmonary hypoplasia and persistent pulmonary hypertension (PPH) are the principal causes of the ongoing mortality in congenital diaphragmatic hernia (CDH) presenting with respiratory insufficiency within 6 hours after birth. Endothelin-1 (ET-1) is an endothelial-derived vasoconstrictor, which could play an important role in modulating pulmonary vascular tone in PPH. ET-1 exerts its role in controlling vascular tone through two different subtype receptors, endothelin-A receptor (ETA) which is responsible for vasoconstriction and endothelin-B receptor (ETB) which is responsible for vasodilatation by induction of nitric oxide synthase.. We examined the pulmonary expression of ET-1, ETA and ETB mRNAs in a rat model of CDH. CDH was induced in rats by administration of 100 mg of nitrofen dissolved in olive oil on day 10 of gestation. Fetal lungs were collected after cesarean section on gestational day 22 (term) and processed for Northern blot analysis and quantitative polymerase chain reaction (PCR).. Significantly (P<.05) enhanced levels of ET-1 mRNA were observed in CDH rats compared with control rats. In contrast to equal levels of ETB mRNA, a two- to fourfold increase in ETA mRNA levels were observed in CDH as compared with control rats.. The upregulated expression of ET-1 and ETA receptor mRNA before birth strongly support the reason for pulmonary vasoconstriction and altered pulmonary vascular muscularization in CDH. Consequently in the clinical setting, the use of endothelin receptor blockade for the treatment of PPH may be considered against the background of the unpredictable and variable response to inhaled nitric oxide in newborns with CDH.

Topics: Animals; Blotting, Northern; Endothelin-1; Female; Gene Expression; Hernia, Diaphragmatic; Hernias, Diaphragmatic, Congenital; Humans; Infant, Newborn; Lung; Persistent Fetal Circulation Syndrome; Phenyl Ethers; Polymerase Chain Reaction; Rats; Rats, Sprague-Dawley; Receptor, Endothelin A; Receptor, Endothelin B; Receptors, Endothelin; RNA, Messenger; Up-Regulation; Vasoconstriction

Pulmonary hypertension is an important cause of mortality in infants with congenital diaphragmatic hernia (CDH). Endothelin-1 has been implicated as a mediator of pulmonary hypertension. ET-A receptors are increased in the nitrofen model of CDH in rats. We hypothesized that vasoconstrictor responses to endothelin-1 are increased in pulmonary arterioles of rats with nitrofen-induced CDH.. CDH was induced in fetal rats by feeding nitrofen (2,4-dichlorophenyl-p-nitrophenyl ether) to pregnant rats at midgestation. Third-generation pulmonary arterioles were isolated on the final day of gestation. Arterioles were cannulated and perfused at constant pressure with a physiologic salt solution. Diameters of arterioles from control animals (n = 8), CDH animals (n = 5), and animals exposed to nitrofen but without CDH (n = 4) were measured. Responses to endothelin-1 concentrations of 10(-12) to 10(-8) M were compared by Student's t test.. CDH arterioles constricted more than controls in response to endothelin-1 at concentrations of 10(-11) M (29 +/- 11% vs 5 +/- 3%, P = 0.02) and 10(-10) M (40 +/- 14% vs 9 +/- 6%, P = 0.04). The log concentration of endothelin-1 that induced half-maximal response (ED50) was lower for CDH arterioles than for control arterioles (-10.3 +/- 0.6 vs -9.1 +/- 0.2, P = 0.03). Responses of arterioles from animals exposed to nitrofen but without CDH were not different from controls (P > or = 0.05).. Exaggerated vasoconstrictor responses to endothelin-1 may contribute to pulmonary hypertension in CDH.

Topics: Animals; Arterioles; Disease Models, Animal; Endothelin-1; Female; Herbicides; Hernias, Diaphragmatic, Congenital; Hypertension, Pulmonary; Lung; Phenyl Ethers; Pregnancy; Prenatal Exposure Delayed Effects; Pulmonary Artery; Rats; Rats, Sprague-Dawley; Vasoconstriction