Signaling of Prostaglandin E Receptors, EP3 and EP4 Facilitates Wound Healing and Lymphangiogenesis with Enhanced Recruitment of M2 Macrophages in Mice.

Lymphangiogenesis plays an important role in homeostasis, metabolism, and immunity, and also occurs during wound-healing. Here, we examined the roles of prostaglandin E2 (PGE2) receptor (EP) signaling in enhancement of lymphangiogenesis in wound healing processes. The hole-punch was made in the ears of male C57BL/6 mice using a metal ear punch. Healing process and lymphangiogenesis together with macrophage recruitment were analyzed in EP knockout mice. Lymphangiogenesis was up-regulated in the granulation tissues at the margins of punched-hole wounds in mouse ears, and this increase was accompanied by increased expression levels of COX-2 and microsomal prostaglandin E synthase-1. Administration of celecoxib, a COX-2 inhibitor, suppressed lymphangiogenesis in the granulation tissues and reduced the induction of the pro-lymphangiogenic factors, vascular endothelial growth factor (VEGF) -C and VEGF-D. Topical applications of selective EP receptor agonists enhanced the expressions of lymphatic vessel endothelial hyaluronan receptor-1 and VEGF receptor-3. The wound-healing processes and recruitment of CD11b-positive macrophages, which produced VEGF-C and VEGF-D, were suppressed under COX-2 inhibition. Mice lacking either EP3 or EP4 exhibited reduced wound-healing, lymphangiogenesis and recruitment of M2 macrophages, compared with wild type mice. Proliferation of cultured human lymphatic endothelial cells was not detected under PGE2 stimulation. Lymphangiogenesis and recruitment of M2 macrophages that produced VEGF-C/D were suppressed in mice treated with a COX-2 inhibitor or lacking either EP3 or EP4 during wound healing. COX-2 and EP3/EP4 signaling may be novel targets to control lymphangiogenesis in vivo.

Telomere lengths at birth in trisomies 18 and 21 measured by Q-FISH.

Trisomies 18 and 21 are genetic disorders in which cells possess an extra copy of each of the relevant chromosomes. Individuals with these disorders who survive birth generally have a shortened life expectancy. As telomeres are known to play an important role in the maintenance of genomic integrity by protecting the chromosomal ends, we conducted a study to determine whether there are differences in telomere length at birth between individuals with trisomy and diploidy, and between trisomic chromosomes and normal chromosomes. We examined samples of peripheral blood lymphocytes (PBLs) from 31 live neonates (diploidy: 10, trisomy 18: 10, trisomy 21: 11) and estimated the telomere length of each chromosome arm using Q-FISH. We observed that the telomeres of trisomic chromosomes were neither shorter nor longer than the mean telomere length of chromosomes as a whole among subjects with trisomies 18 and 21 (intra-cell comparison), and we were unable to conclude that there were differences in telomere length between 18 trisomy and diploid subjects, or between 21 trisomy and diploid subjects (inter-individual comparison). Although it has been reported that telomeres are shorter in older individuals with trisomy 21 and show accelerated telomere shortening with age, our data suggest that patients with trisomies 18 and 21 may have comparably sized telomeres. Therefore, it would be advisable for them to avoid lifestyle habits and characteristics such as obesity, cigarette smoking, chronic stress, and alcohol intake, which lead to marked telomere shortening.

Dextro-transposition of the great arteries in a neonate with ventricular septal defect and pulmonary stenosis complicated by premature closure of the ductus arteriosus and possible pathophysiology of both defects.

Premature closure of the ductus arteriosus (PCDA) and transposition of the great arteries (TGA) cause persistent pulmonary hypertension of the newborn (PPHN). We present a case of a newborn who demonstrated d-TGA with ventricular septal defect (VSD) and pulmonary stenosis (PS) complicated by PCDA. The neonate showed severe cyanosis resistant to resuscitation soon after birth, and was diagnosed with d-TGA with VSD by echocardiography. PPHN was also suspected based on physical symptoms and results of echocardiography. The neonate was given inhaled nitric oxide, prostaglandin E1, and catecholamines under sedation, and underwent a balloon atrial septostomy (BAS). His condition gradually improved, and he was extubated on day 7, but his pulmonary subvalvular stenosis gradually worsened and pulmonary blood flow was markedly decreased. A second BAS was performed on day 27 and he showed no improvement. Blalock-Taussig shunt surgery was performed on day 34, which markedly improved his condition. The co-existence of d-TGA and PCDA is generally a lethal state. In our patient, an increase in pulmonary blood flow during the fetal period was restricted because of PS and outlet flow from the left ventricle to the right ventricle via the VSD. This restricted blood flow through the ductus arteriosus, which led to narrowing of the DA. At the same time, damage to and constrictive changes of the pulmonary vessels were prevented. The ductus arteriosus should be carefully evaluated to exclude PCDA in cases of d-TGA. The presence of both VSD and PS may be a prognostic factor in such cases.

Effects of indomethacin on patent ductus arteriosus in neonates with genetic disorders and/or congenital anomalies.

OBJECTIVES: The study aimed to evaluate the effectiveness of intravenous indomethacin (IND) therapy for patent ductus arteriosus (PDA) in neonates with genetic disorders and/or congenital anomalies soon after birth. STUDY DESIGN: A total of 301 neonates with a genetic disorder and/or congenital anomalies and with a gestational age of ≥ 35 weeks were admitted during the study period. Eighty-five neonates with 56 genetic disorders (30 cases of trisomy 21, 10 cases of trisomy 18, and 16 others) and 29 congenital anomalies, and with clinical symptoms received intravenous IND therapy. The management methods were similar to those used for PDA in low-birth-weight infants. RESULTS: IND therapy had a clinical benefit at a high rate of 79% in these patients (90% and 70% in neonates with trisomies 21 and 18, respectively), including complete closure of the PDA in 52% of the patients. Although oliguria was observed in 43 infants (51%) and slight gastrointestinal bleeding was observed in 12 (14%), no infants had severe complications such as intracranial bleeding. CONCLUSIONS: IND therapy is an effective treatment option before considering surgery for PDA in neonates with genetic disorders and/or congenital anomalies. This therapy may reduce the difficulty of treatment in the acute stage among these neonates.

Long survival of congenital alveolar capillary dysplasia patient with NO inhalation and epoprostenol: effect of sildenafil, beraprost and bosentan.

The case is described herein of a patient with alveolar capillary dysplasia with double-outlet right ventricle and duodenal atresia who survived for a remarkably long time. The newborn girl was born at a gestational age of 36 weeks and weighed 1926 g. One min after delivery the Apgar score was 4. The patient had persistent pulmonary hypertension (PH) and needed nitric oxide inhalation and i.v. epoprostenol all through her life. Although other oral medications for PH were tried, they could not be used in practice because of gastrointestinal complications. The patient died on the 237 th day of life as a result of worsening PH associated with infection.

Characteristics of weak base-induced vacuoles formed around individual acidic organelles.

We have previously found that the weak base 4-aminopyridine induces Brownian motion of acidic organelles around which vacuoles are formed, causing organelle traffic disorder in neurons. Our present study investigated the characteristics of vacuoles induced by weak bases (NH(4)Cl, aminopyridines, and chloroquine) using mouse cells. Individual vacuoles included acidic organelles identified by fluorescent protein expression. Mitochondria and actin filaments were extruded outside the vacuoles, composing the vacuole rim. Staining with amine-reactive fluorescence showed no protein/amino acid content in vacuoles. Thus, serous vacuolar contents are probably partitioned by viscous cytosol, other organelles, and cytoskeletons, but not membrane. The weak base (chloroquine) was immunochemically detected in intravacuolar organelles, but not in vacuoles. Early vacuolization was reversible, but long-term vacuolization caused cell death. The vacuolization and cell death were blocked by the vacuolar H(+)-ATPase inhibitor and Cl--free medium. Staining with LysoTracker or LysoSensor indicated that intravacuolar organelles were strongly acidic and vacuoles were slightly acidic. This suggests that vacuolization is caused by accumulation of weak base and H(+) in acidic organelles, driven by vacuolar H(+)-ATPase associated with Cl(-) entering, and probably by subsequent extrusion of H(+) and water from organelles to the surrounding cytoplasm.

Cardiac surgery in patients with trisomy 18.

Cardiac surgery is infrequently but increasingly being used to repair congenital heart defects associated with trisomy 18. The clinical details of trisomy 18 patients undergoing cardiac surgery have rarely been reported. Seventeen patients with trisomy 18 and serious cardiac symptoms underwent cardiac surgery in our institution. Age at surgery ranged from 7 to 258 days (median, 66 days). One patient had an atrioventricular septal defect and coarctation of the aorta. The remaining patients had ventricular septal defects, including four patients with coarctation of the aorta. Fourteen patients had associated patent ductus arteriosus. Fourteen patients underwent palliative surgery without cardiopulmonary bypass, and four of these underwent a second-stage intracardiac repair. The other three patients underwent primary intracardiac repair. Postoperatively, 14 patients (82%) were discharged home with improved symptoms. Survival from birth ranged from 12 to 1384 days (median, 324 days). Eight patients survived longer than 1 year. Median postoperative survival was 179 days. Postoperative survival was significantly better after palliative surgery (0 to 1239 days; median, 257 days) than after primary intracardiac repair (1 to 179 days; median, 48 days). Only one patient died of heart failure, suggesting that cardiac surgery was effective in preventing heart failure-related death.

Intensive cardiac management in patients with trisomy 13 or trisomy 18.

Intensive cardiac management such as pharmacological intervention for ductal patency (indomethacin and/or mefenamic acid for closure and prostaglandin E1 for maintenance) and palliative or corrective surgery is a standard treatment for congenital heart defects. However, whether it would be a treatment option for children with trisomy 13 or trisomy 18 syndrome is controversial because the efficacy on survival in patients with these trisomies has not been evaluated. We retrospectively reviewed 31 consecutive neonates with trisomy 13 or trisomy 18 admitted to our neonatal ward within 6 hr of birth between 2000 and 2005. The institutional management policies differed during three distinct periods. In the first period, both pharmacological ductal intervention and cardiac surgery were withheld. In the second, pharmacological ductal intervention was offered as an option, but cardiac surgery was withheld. Both strategies were available during the third period. The median survival times of 13, 9, and 9 neonates from the first, second, and third periods were 7, 24, and 243 days, respectively. Univariate and multivariate analyses confirmed that the patients in the third period survived significantly longer than the others. Intensive cardiac management consisting of pharmacological intervention for ductal patency and cardiac surgery was demonstrated to improve survival in patients with trisomy 13 or trisomy 18 in this series. Therefore, we suggest that this approach is a treatment option for cardiac lesions associated with these trisomies. These data are helpful for clinicians and families to consider in the optimal treatment of patients with these trisomies.

Vesicle disruption, plasma membrane bleb formation, and acute cell death caused by illumination with blue light in acridine orange-loaded malignant melanoma cells.

Acridine orange (AO), a weakly basic fluorescent dye, is permeable to plasma and vesicle membranes and preferentially remains in intracellular acidic regions. Using fluorescence microscopy, we observed dynamic changes in AO-loaded cultured malignant melanoma cells during illumination with blue light. Immediately after the start of the illumination, the successive disruption of vesicles was observed as a flash of fluorescence, and shortly after that, blebs were formed on the plasma membrane. These cells died within 5 min. Vesicle disruption was completely inhibited when cells were treated with the vacuolar H(+)-ATPase inhibitor bafilomycin A1 followed by loading with AO, but not when bafilomycin A1 was treated after AO loading. Thus, the filling of AO in the vesicle, which is driven by vacuolar H(+)-ATPase, is initially required for vesicle disruption. In contrast, bafilomycin A1 did not prevent plasma membrane blebbing, indicating that the blebs are formed independently of the vesicle disruption. Acute cell death was inhibited by treatment with bafilomycin A1 before but not after AO loading. Thus, AO- and blue light-induced acute cell death is associated with vesicle disruption rather than bleb formation. Both the vesicle disruption and the formation of plasma membrane blebs were inhibited by removal of oxygen from the cell environment and by singlet oxygen scavengers, sodium azide, ascorbic acid, and L-histidine, but not inhibited by the hydroxyl radical scavenger dimethyl thiourea. Acute cell death was also prevented by singlet oxygen scavengers but not by dimethyl thiourea. Thus, these phenomena are likely caused at least in part by the generation of singlet oxygen. The photosensitive features of plasma and vesicle membranes observed in the present study may be based on the use of the photodynamic effect, such as cancer therapy.

Ratio of circulating follistatin and activin A reflects the severity of acute liver injury and prognosis in patients with acute liver failure.

BACKGROUND AND AIM: The activin A-follistatin system is known to play a critical role in hepatocyte regeneration during the repair of liver tissue. However, the relationship between blood levels of these compounds and the severity and prognosis of acute liver injury remains unclear. The aim of this study was to evaluate the clinical significance of circulating activin A and follistatin in patients with acute liver disease. METHODS: Serum activin A and plasma follistatin levels were determined on admission by enzyme-linked immunosorbent assay in 32 patients with acute hepatitis (AH), 23 patients with acute severe hepatitis (ASH) and 16 patients with acute liver failure (ALF). RESULTS: Both serum activin A and plasma follistatin levels were significantly elevated in patients with ASH and ALF when compared with those in patients with AH and normal controls (NC). Although plasma follistatin levels were significantly and positively correlated with serum activin A levels (r = 0.413, P < 0.001), the follistatin and activin A (F/A) ratio showed distinct deviation from NC between AH and ALF patients. The F/A ratio in AH patients was significantly elevated when compared with NC, but was significantly reduced in ALF patients. Furthermore, the F/A ratio in non-surviving ALF patients was significantly lower than that in survivors. Levels of serum activin A and plasma follistatin were significantly and negatively correlated with prothrombin time (PT) and normotest (NT) levels, while the F/A ratio showed significant and positive correlations with PT and NT. CONCLUSIONS: Decreased blood F/A ratio in ALF patients may be a reliable indicator of the severity of acute liver injury and prognosis in ALF.

[Retinopathy of prematurity in extremely low birth weight infants: a Tokyo multicenter study].

OBJECTIVE: To investigate how the increase in survival rate in extremely low birth weight (a birth weight of 1,000 g or less) infants had affected the incidence of retinopathy of prematurity (ROP) and the frequency of laser treatment. METHODS: We retrospectively reviewed the medical records of 122 surviving premature infants with birthweights less than 1,000 g to determine the severity of ROP observed at 16 neonatal intensive care units in Tokyo between April and October 2002. RESULTS: The survival rate was 85.6%. The mean gestational age was 26.74 weeks and the mean birth weight was 782.25 g. One-hundred-and-five infants (86.1%) developed ROP, fifty (41.0%) received laser treatment, and six (4.9%) had retinal detachment. The median postmenstrual age (gestational age at birth plus chronological age in weeks, PMA) at the onset of ROP was 32.5 weeks, and the first laser treatment was performed at the median PMA of 35.7 weeks. CONCLUSIONS: In these extremely low birth weight infants, there was an increase in the survival rate and in the incidence of severe ROP that progressed to the stage that required treatment.

Correlation between semaphorin3A-induced facilitation of axonal transport and local activation of a translation initiation factor eukaryotic translation initiation factor 4E.

An impressive body of evidence has been accumulated indicating that local protein synthesis is implicated in navigation of neurite extension induced by guidance cues, such as semaphorin3A (Sema3A). We found previously that a Src type tyrosine kinase Fyn and cyclin-dependent kinase 5 (Cdk5) mediate Sema3A-signaling. We also showed that Sema3A elicits axonal transport through neuropilin-1, a receptor for Sema3A, located at the growth cones. Here, we investigate the relationship between Sema3A-induced local signaling, protein synthesis, and axonal transport. Lavendustin A, a tyrosine kinase inhibitor, and olomoucine, a cyclin-dependent kinase inhibitor, suppressed Sema3A-induced facilitation of anterograde and retrograde axonal transport in dorsal root ganglion (DRG) neuron with and without the cell body. Sema3A-induced facilitation of axonal transport was attenuated in DRG neurons of fyn- (fyn-/-) and a Cdk5 activator, p35 (p35-/-)-deficient mice when compared with those of wild-type or heterozygous mice. Inhibition of protein synthesis suppressed Sema3A-induced facilitation of axonal transport in the DRG neuron with and without the cell body. Sema3A enhanced the level of immunoreactivity of phosphorylated eukaryotic translation initiation factor 4E (eIF-4E) within 5 min in growth cones in a time course similar to that of the facilitated axonal transport. This enhanced signal for phospho-eIF4E was blocked by lavendustin A or olomoucine and was not detected in the fyn-/- and p35-/- neurons. These results provide evidence for a mutual regulatory mechanism between local protein synthesis and axonal transport.

Nitric oxide generated by iNOS reduces deformability of Lewis lung carcinoma cells.

Previous studies have indicated that NO plays a crucial role in the metastasis of tumor cells and that tumor cells produce nitric oxide (NO) via inducible nitric oxide synthase (iNOS). Since the deformability of tumor cells is an important factor governing their metastatic potential, in this study we investigated the regulation of tumor cell deformability by NO. Lewis lung tumor cells (3LL cells) were also incubated with a cytokine mixture (IL-1 beta, IFN gamma, and TNF alpha). The nitrite/nitrate content of the supernatant was then measured by the Griess method, and iNOS expression was evaluated by RT-PCR in vitro. Nitrite/nitrate was produced in response to administration of the cytokine mixture, and iNOS mRNA was expressed in the cytokine-treated cells. The deformability of the 3LL cells was evaluated by measuring the peak pressure generated during their passage through a microfilter at a constant flow rate. Both the cytokine mixture and NO donor (NOC 18) significantly increased the filtration pressure, and the staining of the cells with rhodamine-phalloidin revealed assembly of F-actin in the cell membrane. In conclusion, NO plays a role in the decreased deformability of tumor cells, suggesting that NO is one of the factors that regulates metastasis.

Expression of neurotrophins and their receptors in peripheral lung cells of mice.

Neurotrophins play an essential role in nerve systems. Recent reports indicated that neurotrophins [nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and neurotrophin-4/5 (NT-4/5)] have numerous effects on non-neural cells, especially on immune cells. However, whether lung cells express neurotrophins and/or their receptors (TrkA for NGF, TrkB for BDNF and NT-4/5, and TrkC for NT-3) has never been systematically investigated. We investigated constitutive expression of neurotrophin family and their Trk receptor family in alveolar macrophages and other peripheral lung cells of mice. New findings were: (1) RT-PCR for neurotrophins and their receptors detected NT-3 and NT-4/5 in alveolar macrophages, BDNF, NT-4/5, trkA, the truncated form of trkB, and trkC in lung homogenate, but no trks in alveolar macrophages, (2) immunohistochemistry for neurotrophin receptors detected TrkA in capillary cells, the truncated form of TrkB, and TrkC in interstitial macrophages, (3) immunoelectron microscopy for TrkC revealed expression of TrkC on the surface of interstitial macrophages, and (4) in situ hybridization for neurotrophins detected BDNF in interstitial macrophages and alveolar type I cells, NT-3 in alveolar macrophages, and NT-4/5 in alveolar and interstitial macrophages. These findings indicate that a previously unknown signal trafficking occurs through neurotrophins in peripheral lung.