Acute venodilation properties of low-dose intravenous nitroglycerine in pulmonary veno-occlusive disease: a case report.

Background: The use of pulmonary vasodilators for pulmonary arterial hypertension (PAH) has led to a favourable prognosis. In contrast, pulmonary veno-occlusive disease (PVOD) is characterized by the possibility of severe pulmonary oedema after specific PAH therapy. Pulmonary oedema presumably develops in association with pulmonary arterial vasodilation without concomitant pulmonary venodilation. The venous circulation maximally dilates with small amounts of nitroglycerine. Case summary: A 59-year-old woman with advanced PVOD was referred to our hospital. We performed a right heart catheterization after administering combination therapy with selexipag and macitentan, and intravenous nitroglycerine at 0.2 and 0.4 µg/kg/min decreased pulmonary arterial wedge pressure (PAWP) and mean pulmonary arterial pressure (PAP) to minimal levels. The final dose of 1 µg/kg/min yielded an ∼20% decrease in mean PAP and pulmonary vascular resistance (PVR). Discussion: Here, we described the acute effect of intravenous nitroglycerine on PAWP and PVR in a patient with PVOD. This case highlights the venodilation response even in advanced PVOD, suggesting the importance of further research into selective venous dilators as potent therapy.

Prostacyclin receptor agonists induce DUSP1 to inhibit pulmonary artery smooth muscle cell proliferation.

AIMS: Upregulated p38MAPK signaling is implicated in the accelerated proliferation of pulmonary artery smooth muscle cells (PA-SMCs) and the pathogenesis of pulmonary artery remodeling observed in pulmonary arterial hypertension (PAH). Previously, we reported that after endothelin-1 (ET-1) pretreatment, bone morphogenetic protein 2 (BMP2) activates p38MAPK signaling and accelerates PA-SMC proliferation. The activity of p38MAPK signaling is tightly regulated by the inactivation of dual-specificity phosphatase 1 (DUSP1). Activated p38MAPK induces DUSP1 expression, forming a negative feedback loop. Prostacyclin IP receptor agonists (prostacyclin and selexipag) are used to treat PAH. In this study, we aimed to verify whether IP receptor agonists affect DUSP1 expression and accelerate the proliferation of PA-SMCs. MAIN METHODS: PA-SMCs were treated with BMP2, ET-1, prostacyclin, and MRE-269, an active metabolite of selexipag, either alone or in combination. We quantified mRNA expressions using real-time quantitative polymerase chain reaction. Pulmonary artery specimens and PA-SMCs were obtained during lung transplantation in patients with PAH. KEY FINDINGS: Both prostacyclin and MRE-269 increased DUSP1 expression. Combined treatment with BMP2 and ET-1 induced cyclin D1 and DUSP1 expression and increased PA-SMC proliferation. MRE-269 attenuated BMP2/ET-1-induced cell proliferation. ET-1 increased DUSP1 expression in PA-SMCs from control patients but not in PA-SMCs from patients with PAH. SIGNIFICANCE: This study showed that the p38MAPK/DUSP1 negative feedback loop is impaired in PAH, contributing to unregulated p38MAPK activation and PA-SMC hyperplasia. IP receptor agonist MRE-269 increases DUSP1 expression and inhibit p38MAPK-mediated PA-SMC proliferation. Future elucidation of the detailed mechanism underlying reduced DUSP1 expression would be informative for PAH treatment.

Endothelin-1 alters BMP signaling to promote proliferation of pulmonary artery smooth muscle cells.

Pulmonary arterial hypertension (PAH) is characterized by abnormal outgrowth of pulmonary artery smooth muscle cells (PASMCs) of the media. Abundant expression of endothelin-1 (ET-1) and activated p38 mitogen-activated protein kinase (p38MAPK) has been observed in PAH patients. p38MAPK has been implicated in cell proliferation. An unspecified disturbance in bone morphogenetic protein (BMP) signaling may be involved in the development of PAH. Type I receptors (BMPR1A and BMPR1B) and type II receptor (BMPR2) transduce signals via two distinct pathways, i.e., canonical and non-canonical pathways, activating Smad1/5/8 and p38MAPK, respectively. BMPR1B expression was previously reported to be enhanced in the PASMCs of patients with idiopathic PAH. BMP15 binds specifically to BMPR1B. We assessed the effects of ET-1 on BMP receptor expression and cell proliferation. BMP2 increased BMPR1B expression in human PASMCs after pretreatment with ET-1 in vitro. Although BMP2 alone did not affect PASMC proliferation, BMP2 treatment after ET-1 pretreatment significantly accelerated PASMC proliferation. PH-797804, a selective p38MAPK inhibitor, abrogated this proliferation. Similarly, after ET-1 pretreatment, BMP15 significantly accelerated the proliferation of PASMCs, whereas stimulation with BMP15 alone did not. In conclusion, in PASMCs, ET-1 exposure under pathological conditions alters BMP signaling to activate p38MAPK, resulting in cell proliferation.

Giant coronary fistula aneurysm presenting as a progressing left-sided asymptomatic mediastinal mass with systolic dominant Doppler flow: a case report.

BACKGROUND: Cases of giant coronary artery aneurysms (GCAAs) associated with coronary fistula are rarely reported, and they present with various symptoms, including coronary steal syndrome. We report an uncommon case of an asymptomatic giant coronary fistula aneurysm presenting as a progressing left-sided mediastinal mass that has been tracked for years. CASE SUMMARY: A 67-year-old healthy asymptomatic woman was referred to our hospital because of an abnormal shadow on her chest radiography revealing a left-sided mediastinal mass that had progressed in size over the past 4 years. Computed tomography revealed mass progression from 4 to 5 cm in diameter within 2 years. Coronary computed tomography and coronary angiography identified a GCAAs in a coronary fistula originating in the left anterior descending artery and draining into the main pulmonary artery. Transthoracic Doppler echocardiography revealed a unique systolic dominant flow. She underwent coronary artery aneurysmectomy and fistula ligation. The patient has been in good health without any events for 10 months since her discharge. DISCUSSION: A GCAAs in a coronary fistula can present as an asymptomatic left-sided mediastinal mass that has progressed in size for years in older adults. Echocardiography can provide clues of the steal phenomenon in coronary artery fistula. A close investigation of mediastinal abnormalities can facilitate the detection of coronary aneurysms.

Administration of ß-lactam antibiotics and delivery method correlate with intestinal abundances of Bifidobacteria and Bacteroides in early infancy, in Japan.

The intestinal microbiome changes dynamically in early infancy. Colonisation by Bifidobacterium and Bacteroides and development of intestinal immunity is interconnected. We performed a prospective observational cohort study to determine the influence of antibiotics taken by the mother immediately before delivery on the intestinal microbiome of 130 healthy Japanese infants. Faecal samples (383) were collected at 1, 3, and 6 months and analysed using next-generation sequencing. Cefazolin was administered before caesarean sections, whereas ampicillin was administered in cases with premature rupture of the membranes and in Group B Streptococcus-positive cases. Bifidobacterium and Bacteroides were dominant (60-70% mean combined occupancy) at all ages. A low abundance of Bifidobacterium was observed in infants exposed to antibiotics at delivery and at 1 and 3 months, with no difference between delivery methods. A lower abundance of Bacteroides was observed after caesarean section than vaginal delivery, irrespective of antibiotic exposure. Additionally, occupancy by Bifidobacterium at 1 and 3 months and by Bacteroides at 3 months differed between infants with and without siblings. All these differences disappeared at 6 months. Infants exposed to intrapartum antibiotics displayed altered Bifidobacterium abundance, whereas abundance of Bacteroides was largely associated with the delivery method. Existence of siblings also significantly influenced the microbiota composition of infants.

Endothelin-1 induces lysyl oxidase expression in pulmonary artery smooth muscle cells.

The increase in thickening of the arterial wall of pulmonary arterial hypertension (PAH) includes cellular proliferation as well as matrix deposition and interrupted internal elastic lamina (IEL) consisting of a thick homogeneous sheet of elastin. Little is, although, known about the detail of IEL formation in PAH. Endothelin-1 is overexpressed in pulmonary arterioles of PAH. We aimed to examine the expression of genes contributing to IEL formation in pulmonary artery smooth muscle cells (PASMCs) especially focused on lysyl oxidase (LOx), an exreacellular matrix enzyme that catalyzes the cross-linking of collagens or elastin. We quantified mRNA expressions of genes contributing to IEL formation including LOx in PASMCs using real-time quantitative polymerase chain reaction. We stimulated human PASMCs with endothelin-1 with prostacyclin or trapidil. Endothelin-1 significantly increased LOx expression. Prostacyclin and trapidil restored endothelin-1-induced LOx expression to the basal level. Endothelin-1 increased LOx expression strongly in PASMCs from PAH patients compared to those from controls. Trapidil reduced LOx expression only in PASMCs from PAH patients. Overexpressed endothelin-1 in PAH patients can increase expression of LOx and agitate cross-linking of elastin and collagen, resulting in ectopic deposition of these in the vascular media.

Successful Liposteroid Therapy for a Recurrent Idiopathic Pulmonary Hemosiderosis with Down Syndrome.

Idiopathic pulmonary hemosiderosis (IPH) is a rare and life-threatening disorder. Early diagnosis and appropriate management are essential for their better prognosis and patients' quality of life (QOL). It is considered that Down syndrome patients with IPH have a worse prognosis compared to other IPH cases. A 2-year-old girl with Down syndrome received the diagnosis of IPH after two episodes of massive pulmonary hemorrhage requiring assist ventilation, who suffered from recurrent IPH during tapering period of oral corticosteroid, started liposteroid therapy. We report here a case of successful control of recurrent IPH and improved QOL enormously with tapering dose of corticosteroid after starting liposteroid therapy.

Maternal antimicrobial use at delivery has a stronger impact than mode of delivery on bifidobacterial colonization in infants: a pilot study.

OBJECTIVE: To investigate factors related to bifidobacterial colonization in early infancy, with a focus on maternal antimicrobial use at delivery. STUDY DESIGN: A cross-sectional pilot study was performed. Feces samples of 33 Japanese healthy infants were collected over 10 months and analyzed by next-generation sequencing to examine the diversity and abundance of the gut microbiota. RESULTS: The beta diversity index of the gut microbiota differed significantly based on maternal antimicrobial use at delivery (P < 0.05). The most dominant genus was bifidobacteria, and the relative abundance of bifidobacteria in infants exposed to maternal antibiotics was significantly lower than in those who were not exposed (P < 0.05). In contrast, the delivery mode showed no significant relationship with gut microbiota diversity. CONCLUSIONS: Maternal antimicrobial use at delivery has a stronger effect than delivery mode on the gut microbiota, especially for colonization of bifidobacteria.

Bosentan reverses the hypoxia-induced downregulation of the bone morphogenetic protein signaling in pulmonary artery smooth muscle cells.

AIMS: Pulmonary hypertension (PH) is a common complication of chronic hypoxic lung diseases. Bone morphogenetic protein (BMP) and endothelin-1 signaling pathways have been shown to be altered in hypoxic PH and to play crucial roles in the associated pulmonary artery remodeling. We, therefore, aimed to study the potential link between hypoxia and the alteration of BMP and endothelin-1 signaling observed in pulmonary artery smooth muscle cells (PA-SMCs) in hypoxic PH. MATERIALS AND METHODS: Human PA-SMCs were treated with hypoxia-mimetic agent cobalt chloride (CoCl2; 100µM), with or without pretreatment with a dual endothelin receptor antagonist bosentan (10µM). Expressions of preproendothelin-1 (PPET1), BMP type 2 receptor (BMPR-2), and one BMP signaling target gene, the inhibitor of DNA binding 1 (ID1) were evaluated by real time quantitative polymerase chain reaction. BMP2-treated PA-SMCs were assessed for Smad1/5/8 signaling activation by Western Blotting. KEY FINDINGS: Treatment of PA-SMCs with CoCl2 increased PPET1 gene expression, while it did not alter expressions of endothelin converting enzyme, endothelin receptor type A or type B. Hypoxia-mimetic agent CoCl2 decreased the expressions of BMPR-2 and ID1 maximally after 3- and 6-hour treatment respectively, while CoCl2 treatment progressively increased noggin expression. Bosentan pretreatment restored expressions of BMPR-2 and ID1, as well as the activation (by phosphorylation) of Smad1/5/8 signaling induced by BMP2. SIGNIFICANCE: Hypoxia induces the downregulation of the BMP signaling in PA-SMCs, at least, partly through the endothelin system. In hypoxic PH, increased endothelin-1 production might therefore contribute to the altered BMP signaling and subsequent PA-SMC hyperplasia.

Antagonists to endothelin receptor type B promote apoptosis in human pulmonary arterial smooth muscle cells.

AIMS: Vascular remodeling results from aberrations in the balance between cell proliferation and death, which is seen in the obstructive vasculature of pulmonary arterial hypertension (PAH). Endothelin (ET)-1 has a potent proliferative activity on vascular smooth muscle cells, and ET receptor inhibitors are used to treat PAH; however, it remains unclear whether ET receptor inhibition contributes to the apoptosis of pulmonary arterial smooth muscle cells (PASMCs), another cause of pulmonary vascular remodeling. MAIN METHODS: Cultured human PASMCs were treated with the ETA receptor antagonist BQ-123 (100µM), or the ETB antagonist A-192621 (1-100µM) or BQ-788 (1-100µM) for 48h. The cells were then incubated for another 24h with or without doxorubicin (DOX, 1µM), an anthracyclin antitumor antibiotic that promotes p53-mediated apoptosis. Cell viability and apoptosis were evaluated by MTT assays, caspase-3/7 activity assays, and Western blots for cleaved caspase-3 expression. KEY FINDINGS: The viability of PASMCs was significantly decreased by A-192621 and BQ-788, in a dose-dependent manner. A-192621 and BQ-788 significantly increased the caspase-3/7 activity and cleaved caspase-3 expression in PASMCs. The PASMCs' susceptibility to DOX-induced apoptosis was significantly higher in the presence of A-192621 and BQ-788 than with vehicle. However, BQ-123 did not affect these parameters. SIGNIFICANCE: Blockade of the ETB receptor increases the extent of apoptosis and susceptibility to DOX-induced apoptosis in PASMCs. Apoptosis caused by ETB receptor blockade in PASMCs may be one of the mechanisms by which vascular remodeling is reduced in ET receptor inhibitor-based PAH treatments.

Prevention of pulmonary hypoplasia and pulmonary vascular remodeling by antenatal simvastatin treatment in nitrofen-induced congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) has a high mortality rate mainly due to lung hypoplasia and persistent pulmonary hypertension of the newborn (PPHN). Simvastatin has been shown to prevent the development of pulmonary hypertension (PH) in experimental models of PH. We, therefore, hypothesized that antenatal simvastatin would attenuate PPHN in nitrofen-induced CDH in rats. The efficacy of antenatal simvastatin was compared with antenatal sildenafil, which has already been shown to improve pathological features of PPHN in nitrofen-induced CDH. On embryonic day (E) 9.5, nitrofen or vehicle was administered to pregnant Sprague-Dawley rats. On E11, nitrofen-treated rats were randomly assigned to antenatal simvastatin (20 mg·kg(-1)·day(-1) orally), antenatal sildenafil (100 mg·kg(-1)·day(-1) orally), or placebo administration from E11 to E21. On E21, fetuses were delivered by cesarean section, killed, and checked for left-sided CDH. Lung tissue was then harvested for further pathobiological evaluation. In nitrofen-induced CDH, simvastatin failed to reduce the incidence of nitrofen-induced CDH in the offspring and to increase the body weight, but improved the lung-to-body weight ratio and lung parenchyma structure. Antenatal simvastatin restored the pulmonary vessel density and external diameter, and reduced the pulmonary arteriolar remodeling compared with nitrofen-induced CDH. This was associated with decreased lung expression of endothelin precursor, endothelin type A and B receptors, endothelial and inducible nitric oxide synthase, together with restored lung activation of apoptotic processes mainly in the epithelium. Antenatal simvastatin presented similar effects as antenatal therapy with sildenafil on nitrofen-induced CDH. Antenatal simvastatin improves pathological features of lung hypoplasia and PPHN in experimental nitrofen-induced CDH.

Endothelin-Bone morphogenetic protein type 2 receptor interaction induces pulmonary artery smooth muscle cell hyperplasia in pulmonary arterial hypertension.

BACKGROUND: Endothelin receptor antagonists improve pulmonary arterial hypertension (PAH). Mutations in the bone morphogenetic protein (BMP) type 2 receptor (BMPR2) predispose to PAH. Here, we sought to determine whether there might exist interactions between these 2 signaling pathways and their effect on the acquisition of the altered phenotype of pulmonary artery smooth muscle cells (PA-SMCs) observed in PAH. METHODS: Expression of BMPR2, of the BMP agonist BMP4, and of the BMP antagonists gremlin1 and gremlin2 was evaluated in lungs and in PA-SMCs from 6 PAH patients and 14 controls treated with endothelin-1. Endothelin-1 pre-treated PA-SMCs were assessed for proliferation, apoptosis, and downstream signaling activation of Smad1/5/8 and p38 mitogen-activated protein kinase (p38(MAPK)) after BMP2 treatment. RESULTS: In PA-SMCs from PAH patients, expression of BMPR2 and BMP4 decreased, whereas expression of gremlin1 and gremlin2 increased compared with controls. Treatment of control PA-SMCs with endothelin-1 induced a dose-dependent increase in gremlin1 and gremlin2, whereas BMPR2 and BMP4 expression decreased, reaching similar levels as those observed in PAH cells. In control PA-SMCs, endothelin-1 pre-treatment reduced inhibitor of DNA binding 1 (Id1) expression and Smad1/5/8 activation induced by BMP2, whereas it enhanced p38(MAPK) activation. Moreover, BMP2 decreased serum-induced proliferation and increased the pro-apoptotic Bax/Bcl-2 ratio. These effects were attenuated by endothelin-1 pre-treatment. Endothelin-1 did not alter BMPR2 signaling in PA-SMCs from PAH patients. CONCLUSIONS: Endothelin-1 downregulates canonical BMPR2 signaling. This is related to decreased BMPR2 and increased anti-BMP gremlin expression associated with increased activation of p38(MAPK) and results in PA-SMC proliferation.

Effects of selective endothelin (ET)-A receptor antagonist versus dual ET-A/B receptor antagonist on hearts of streptozotocin-treated diabetic rats.

AIMS: The aim was to study the differences in the effectiveness of two types of endothelin (ET) receptor antagonists (selective ET-A or dual ET-A/B antagonists) on the hearts of streptozotocin (STZ)-induced diabetic rats (type I diabetes) at functional and biochemical/molecular levels. MAIN METHODS: Citrate saline (vehicle) or STZ was injected into rats. The ET-A/B dual receptor antagonist (SB209670, 1mg/kg/day) and the ET-A receptor antagonist (TA-0201, 1mg/kg/day) were then administered to these rats. One week after injection, the animals were separated into those receiving SB209670, TA-0201 or vehicle by 4-week osmotic mini-pump. KEY FINDINGS: The VEGF level and percent fractional shortening in the diabetic heart were significantly decreased compared to the non-diabetic heart, whereas SB209670 and TA-0201 treatments greatly and comparably prevented this decrease. SB209670 treatment was more effective in reversing decreased expressions of KDR and phosphorylated AKT, downstream of VEGF angiogenic signaling, than TA-0201 treatment. The eNOS levels in hearts were significantly higher in diabetic rats than in healthy rats, and this increase was significantly reduced by TA-0210 but not by SB209670 treatment. SIGNIFICANCE: Improvement of KDR mRNA and pAKT levels by SB209670 but not TA-0201 suggests that dual ET-A/-B blockade may be effective in improving intracellular systems of these components in the diabetic rat heart. However, the present study also showed that TA-0201 or SB209670 improved percent fractional shortening and VEGF levels of the diabetic hearts to a similar extent, suggesting that ET-A blockade and dual ET-A/-B blockade are similarly effective in improving cardiac dysfunction in the diabetic rats.

Involvement of peptidyl-prolyl isomerase Pin1 in the inhibitory effect of fluvastatin on endothelin-1-induced cardiomyocyte hypertrophy.

AIMS: Cardiac hypertrophy is elicited by endothelin (ET)-1 as well as other neurohumoral factors, hemodynamic overload, and oxidative stress; HMG-CoA reductase inhibitors (statins) were shown to inhibit cardiac hypertrophy partly via the anti-oxidative stress. One of their common intracellular pathways is the phosphorylation cascade of MEK signaling. Pin1 specifically isomerizes the phosphorylated protein with Ser/Thr-Pro bonds and regulates their activity through conformational changes. There is no report whether the Pin1 activation contributes to ET-1-induced cardiomyocyte hypertrophy and whether the Pin1 inactivation contributes to the inhibitory effect of statins. The aim of this study was to reveal these questions. MAIN METHODS: We assessed neonatal rat cardiomyocyte hypertrophy using ET-1 and fluvastatin by the cell surface area, ANP mRNA expression, JNK and c-Jun phosphorylation, and [(3)H]-leucine incorporation. KEY FINDINGS: Fluvastatin inhibited ET-1-induced increase in the cell surface area, ANP expression, and [(3)H]-leucine incorporation; and it suppressed the signaling cascade from JNK to c-Jun. The phosphorylated Pin1 level, an inactive form, was decreased by ET-1; however, it reached basal level by fluvastatin. Furthermore, Pin1 overexpression clearly elicited cardiomyocyte hypertrophy, which was inhibited by fluvastatin. SIGNIFICANCE: This is the first report that ET-1-induced cardiomyocyte hypertrophy is mediated through the Pin1 activation and that the inhibitory effect of fluvastatin on cardiomyocyte hypertrophy would partly be attributed to the suppression of the Pin1 function. This study firstly suggests that Pin1 determines the size of hypertrophied cardiomyocyte by regulating the activity of phosphorylated molecules and that statins exert their pleiotropic effects partly via Pin1 inactivation.

Downregulated bone morphogenetic protein signaling in nitrofen-induced congenital diaphragmatic hernia.

PURPOSE: Bone morphogenetic proteins (BMP) have been shown to play crucial roles in not only lung and heart development, but also in the pathogenesis of pulmonary vascular remodeling in pulmonary hypertension (PH). We therefore hypothesized that BMP signaling could be altered in nitrofen-induced congenital diaphragmatic hernia (CDH) and associated PH. METHODS: Pregnant rats were exposed to either 100 mg nitrofen or vehicle on embryonic day (E) 9.5. On E17 and E21, fetuses were delivered by cesarean section, killed and checked for left-sided CDH. The tissue was then harvested for pathobiological evaluation. RESULTS: In nitrofen-induced CDH, pulmonary expressions of BMP4, BMP receptor (BMPR) type 2 and Id1 decreased on E17 and E21. On E17, pulmonary gremlin-1 expression increased, while BMP7 decreased. In the lungs, Id1 expression was correlated to BMP4 and BMPR2 and inversely correlated to gremlin-1 expression. Myocardial expressions of BMPR2, BMPR1A, BMP7 and SERCA-2A decreased, while gremlin-1 and noggin expressions increased on E17. On E21, myocardial expressions of Id1 and SERCA-2A decreased, while gremlin-1 expression increased. Moreover, BMPR2 and BMPR1A expressions were correlated to SERCA-2A expression and inversely correlated to pro-apoptotic Bax/Bcl2 ratio within the myocardium. CONCLUSION: Downregulation of BMP signaling seems to contribute to pulmonary and myocardial anomalies observed in nitrofen-induced CDH.

Elevation of plasma basic fibroblast growth factor after nocturnal hypoxic events in patients with obstructive sleep apnea syndrome.

Obstructive sleep apnea syndrome (OSAS) is associated with recurrent nocturnal hypoxia during sleep; this hypoxia has been implicated in the pathogenesis of cardiovascular complication. However, a useful soluble factor that is sensitively correlated with OSAS severity for the diagnosis remains unidentified. We hypothesized that systemic levels of basic fibroblast growth factor (bFGF), a hypoxia-induced cytokine, were affected by nocturnal hypoxemia in OSAS patients, and we assessed whether the degree of change in the plasma bFGF concentrations before and after nocturnal hypoxia is correlated with the severity of OSAS. Thirty subjects who had suspected OSAS and had been investigated by nocturnal polysomnography (PSG) were enrolled. Plasma bFGF and vascular endothelial growth factor (VEGF) concentrations the night before PSG and the next morning were measured by sandwich enzyme-linked immunosorbent assay. Correlations between the changes in these factors and hypoxia-associated parameters for OSAS severity were analyzed. Patients with OSAS had significantly elevated levels of plasma bFGF but not VEGF and hemoglobin after rising. The degree of change in bFGF concentrations after nocturnal apnea episodes was significantly correlated with diagnostic parameters for OSAS severity. The change in plasma bFGF levels is associated with the degree of hypoxic state in OSAS patients, implying that bFGF might be a useful soluble factor for evaluating OSAS severity.

Endothelin-1-induced cardiomyocyte hypertrophy is partly regulated by transcription factor II-F interacting C-terminal domain phosphatase of RNA polymerase II.

AIMS: Cardiac hypertrophy is associated with the increase of total amount of RNA, which is in accordance with RNA polymerase II (RNAPII) activation via C-terminal domain (CTD) phosphorylation of the largest subunit of RNAPII. It has been demonstrated that endothelin-1 (ET-1) phosphorylates CTD at the hypertrophic response in cardiomyocytes. However, it is unclear whether ET-1-induced hypertrophy is affected by the CTD phosphatase, transcription factor IIF-interacting CTD phosphatase1 (FCP1). MAIN METHODS: We analyzed whether ET-1-induced cardiomyocyte hypertrophy was affected by overexpression of FCP1 or dominant-negative form of FCP1 (dnFCP1) in neonatal rat cardiomyocytes. KEY FINDINGS: The level of ET-1-induced RNAPII CTD phosphorylation was decreased by FCP1 overexpression, whereas it was sustained by dnFCP1. Global RNA synthesis evaluated by [(3)H]-uridine incorporation showed that the ET-1-induced increase in RNA synthesis was suppressed by FCP1 and was augmented by dnFCP1. ET-1-induced increase in cell surface area was suppressed by FCP1 and was preserved by dnFCP1. Furthermore, the ET-1-induced increase in molecular markers of cardiac hypertrophy, expression of ANP and ß-MHC gene, was suppressed by FCP1 and was not inhibited by dnFCP1. SIGNIFICANCE: ET-1-induced cardiac hypertrophy and CTD phosphorylation level are functionally regulated by FCP1. These findings suggest that FCP1 plays an important role in ET-1-induced cardiac hypertrophy via controlling phosphorylation level of the RNAPII CTD.

Prediction of chronic renal insufficiency after coronary angiography by an early increase in oxidative stress and decrease in glomerular filtration rate.

BACKGROUND: Oxidative stress caused by contrast medium is thought to be one of the main mechanisms of contrast-induced acute kidney injury. A prospective study was conducted to evaluate the relationship between oxidative stress caused by contrast agent administration and long-term renal function. METHODS AND RESULTS: Thirty-six consecutive patients who underwent coronary angiography were enrolled. Urinary F2-isoprostane, a marker of oxidative stress, was measured at baseline and 24h after angiography, and serum creatinine was measured at baseline, 24h and 1 year after the procedure. The change in estimated glomerular filtration rate (eGFR) at 1 year after angiography correlated significantly with the change in eGFR at 24h after angiography (r=0.729, P<0.001). We also found a significant correlation between the increase in urinary F2-isoprostane at 24h and the decrease in eGFR at 1 year (r=0.439, P=0.022). In multivariate analysis, the decrease in eGFR at 1 year after coronary angiography correlated with the increase in F2-isoprostane at 24h after angiography as well as the decrease in eGFR at 24h after angiography (P=0.039 and P<0.001, respectively). CONCLUSIONS: Contrast-induced nephrotoxicity might be transient; however, an early decrease in eGFR and increase in oxidative stress are associated with chronic renal insufficiency. Careful long-term follow-up and adequate medical intervention are necessary for these patients.

VEGF promotes tumorigenesis and angiogenesis of human glioblastoma stem cells.

There is increasing evidence for the presence of cancer stem cells (CSCs) in malignant brain tumors, and these CSCs may play a pivotal role in tumor initiation, growth, and recurrence. Vascular endothelial growth factor (VEGF) promotes the proliferation of vascular endothelial cells (VECs) and the neurogenesis of neural stem cells. Using CSCs derived from human glioblastomas and a retrovirus expressing VEGF, we examined the effects of VEGF on the properties of CSCs in vitro and in vivo. Although VEGF did not affect the property of CSCs in vitro, the injection of mouse brains with VEGF-expressing CSCs led to the massive expansion of vascular-rich GBM, tumor-associated hemorrhage, and high morbidity, suggesting that VEGF promoted tumorigenesis via angiogenesis. These results revealed that VEGF induced the proliferation of VEC in the vascular-rich tumor environment, the so-called stem cell niche.