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Cardiac metabolism is deranged in heart failure, but underlying mechanisms remain unclear. Here, we show that lysine demethylase 8 (Kdm8) maintains an active mitochondrial gene network by repressing Tbx15, thus preventing dilated cardiomyopathy leading to lethal heart failure. Deletion of Kdm8 in mouse cardiomyocytes increased H3K36me2 with activation of Tbx15 and repression of target genes in the NAD+ pathway before dilated cardiomyopathy initiated. NAD+ supplementation prevented dilated cardiomyopathy in Kdm8 mutant mice, and TBX15 overexpression blunted NAD+-activated cardiomyocyte respiration. Furthermore, KDM8 was downregulated in human hearts affected by dilated cardiomyopathy, and higher TBX15 expression defines a subgroup of affected hearts with the strongest downregulation of genes encoding mitochondrial proteins. Thus, KDM8 represses TBX15 to maintain cardiac metabolism. Our results suggest that epigenetic dysregulation of metabolic gene networks initiates myocardium deterioration toward heart failure and could underlie heterogeneity of dilated cardiomyopathy.

Peroxisomes are essential for mitochondrial health. However, the mechanisms underlying the relationship between these two organelles in hepatic metabolism remains unclear. To address this, we developed a conditional hepatocyte specific Pex16 deficient mouse (Pex16 KO) and subjected these animals to a low protein diet to induce metabolic stress. Loss of PEX16 in hepatocytes led to increased biogenesis of small mitochondria and a reduction in autophagy flux but with preserved capacity for respiration and ATP production. Metabolic stress induced by low protein feeding did lead to mitochondrial dysfunction in Pex16 KO mice and impaired the ability to upregulate its biogenesis. Activation of PPARα partially corrected the mitochondrial disturbances caused by low protein feeding, independent of the presence of peroxisomes. This study shows that peroxisome loss in hepatocytes affects mitochondrial biogenesis and autophagy, thereby preserving mitochondrial function and underscore the relation between peroxisomes and mitochondria in regulating the hepatic metabolic responses to nutritional stressors.

Irx1 and Irx2 (Irx1/2) are two closely linked and widely expressed members of the conserved Iroquois homeobox family of transcription factors. Despite mounting evidence suggesting the importance of homologs of these genes in many aspects of vertebrate development and function, the role of Irx1/2 in mammals has remained largely unknown. Here, we used mice carrying our newly generated Irx1flox and Irx1floxIrx2del mutant alleles to perform a stepwise genetic ablation of Irx1 and Irx2 levels. Our analysis revealed reduced postnatal growth and viability of Irx1KO mice with gross histological defects in the lung and gut and demonstrated that ablation of one copy of Irx2 in these mice results in neonatal lethality with exacerbated phenotypic defects. Conversely, while Irx2KO mice appear normal, ablation of one copy of Irx1 in these mutants leads to lethality at weaning. Furthermore, we found that homozygous deletion of both Irx1 and Irx2 results in embryonic lethality by mid-gestation with defective extraembryonic vasculature. Our results illustrate that Irx1 and Irx2 play distinct dose-dependent cooperative functions during both the early and late stages of mouse development.

Background Type 2 diabetes (T2D) is associated with coronary microvascular dysfunction, which is thought to contribute to compromised diastolic function, ultimately culminating in heart failure with preserved ejection fraction (HFpEF). The molecular mechanisms remain incompletely understood, and no early diagnostics are available. We sought to gain insight into biomarkers and potential mechanisms of microvascular dysfunction in obese mouse (db/db) and lean rat (Goto-Kakizaki) pre-clinical models of T2D-associated diastolic dysfunction. Methods The microRNA (miRNA) content of circulating extracellular vesicles (EVs) was assessed in T2D models to identify biomarkers of coronary microvascular dysfunction/rarefaction. The potential source of circulating EV-encapsulated miRNAs was determined, and the mechanisms of induction and the function of candidate miRNAs were assessed in endothelial cells (ECs). Results We found an increase in miR-30d-5p and miR-30e-5p in circulating EVs that coincided with indices of coronary microvascular EC dysfunction (i.e., markers of oxidative stress, DNA damage/senescence) and rarefaction, and preceded echocardiographic evidence of diastolic dysfunction. These miRNAs may serve as biomarkers of coronary microvascular dysfunction as they are upregulated in ECs of the left ventricle of the heart, but not other organs, in db/db mice. Furthermore, the miR-30 family is secreted in EVs from senescent ECs in culture, and ECs with senescent-like characteristics are present in the db/db heart. Assessment of miR-30 target pathways revealed a network of genes involved in fatty acid biosynthesis and metabolism. Over-expression of miR-30e in cultured ECs increased fatty acid β-oxidation and the production of reactive oxygen species and lipid peroxidation, while inhibiting the miR-30 family decreased fatty acid β-oxidation. Additionally, miR-30e over-expression synergized with fatty acid exposure to down-regulate the expression of eNOS, a key regulator of microvascular and cardiomyocyte function. Finally, knock-down of the miR-30 family in db/db mice decreased markers of oxidative stress and DNA damage/senescence in the microvascular endothelium. Conclusions MiR-30d/e represent early biomarkers and potential therapeutic targets that are indicative of the development of diastolic dysfunction and may reflect altered EC fatty acid metabolism and microvascular dysfunction in the diabetic heart.

Necrotizing enterocolitis (NEC) is a devastating neonatal disease characterized by acute intestinal injury. Intestinal stem cell (ISC) renewal is required for gut regeneration in response to acute injury. The Wnt/β-catenin pathway is essential for intestinal renewal and ISC maintenance. We found that ISC expression, Wnt activity and intestinal regeneration were all decreased in both mice with experimental NEC and in infants with acute active NEC. Moreover, intestinal organoids derived from NEC-injured intestine of both mice and humans failed to maintain proliferation and presented more differentiation. Administration of Wnt7b reversed these changes and promoted growth of intestinal organoids. Additionally, administration of exogenous Wnt7b rescued intestinal injury, restored ISC, and reestablished intestinal epithelial homeostasis in mice with NEC. Our findings demonstrate that during NEC, Wnt/β-catenin signaling is decreased, ISC activity is impaired, and intestinal regeneration is defective. Administration of Wnt resulted in the maintenance of intestinal epithelial homeostasis and avoidance of NEC intestinal injury. ispartof: Cell Death & Disease vol:10 issue:10 ispartof: location:England status: published

Mortality in children with severe malnutrition is strongly related to signs of metabolic dysfunction, such as hypoglycemia. Lower circulating tryptophan levels in children with severe malnutrition suggest a possible disturbance in the tryptophan-nicotinamide (TRP-NAM) pathway and subsequently NAD+ dependent metabolism regulator sirtuin1 (SIRT1). We report that severe malnutrition in weanling mice, induced by feeding a low protein diet, leads to an impaired TRP-NAM pathway and affects hepatic mitochondrial turnover and function. We demonstrate that stimulating the TRP-NAM pathway improves hepatic mitochondrial and overall metabolic function which is dependent on SIRT1. Activating SIRT1 is sufficient to induce improvement in metabolic functions. Our findings indicate that modulating the TRP-NAM pathway can partially improve liver metabolic function in severe malnutrition and could lead to the development of new interventions for children with severe malnutrition.

OBJECTIVES: Malnutrition contributes to 45% of the deaths of children

In recent years, China’s cyberspace security is facing increasingly severe challenges. As the national key basic information infrastructure, power control system is very important which is related to the national economy and the people’s livelihood. So network security of power control system should be taken seriously. The network security monitoring capability of power control system has a direct impact on the security of power business such as power production and supply. However, there are few studies on the evaluation of its network security monitoring capability. This paper puts forward the network security monitoring capability evaluation model of power control system based on AHP and fuzzy comprehensive evaluation, according to the research of public network security management capability evaluation, the particularity of network security monitoring system of power control system and the investigation opinions of 20 expert teams in power industry’s network security field. Then, the model is used to evaluate the network security monitoring capability of three municipal power control systems, and the final scores are 93.09, 88.65 and 90.17 respectively. The model established in this paper realizes the quantitative evaluation of the network security monitoring capability of the power control system. And it will help the power company to carry out targeted rectification and improvement according to the calculating result of this model. So the research and application in this paper has a certain practical engineering significance.

Intrinsic ureteropelvic junction obstruction is the most common cause of congenital hydronephrosis, yet the underlying pathogenesis is undefined. Hedgehog proteins control morphogenesis by promoting GLI-dependent transcriptional activation and inhibiting the formation of the GLI3 transcriptional repressor. Hedgehog regulates differentiation and proliferation of ureteric smooth muscle progenitor cells during murine kidney-ureter development. Histopathologic findings of smooth muscle cell hypertrophy and stroma-like cells, consistently observed in obstructing tissue at the time of surgical correction, suggest that Hedgehog signaling is abnormally regulated during the genesis of congenital intrinsic ureteropelvic junction obstruction. Here, we demonstrate that constitutively active Hedgehog signaling in murine intermediate mesoderm–derived renal progenitors results in hydronephrosis and failure to develop a patent pelvic-ureteric junction. Tissue obstructing the ureteropelvic junction was marked as early as E13.5 by an ectopic population of cells expressing Ptch2, a Hedgehog signaling target. Constitutive expression of GLI3 repressor in Ptch1-deficient mice rescued ectopic Ptch2 expression and obstructive hydronephrosis. Whole transcriptome analysis of isolated Ptch2+ cells revealed coexpression of genes characteristic of stromal progenitor cells. Genetic lineage tracing indicated that stromal cells blocking the ureteropelvic junction were derived from intermediate mesoderm–derived renal progenitors and were distinct from the smooth muscle or epithelial lineages. Analysis of obstructive ureteric tissue resected from children with congenital intrinsic ureteropelvic junction obstruction revealed a molecular signature similar to that observed in Ptch1-deficient mice. Together, these results demonstrate a Hedgehog-dependent mechanism underlying mammalian intrinsic ureteropelvic junction obstruction.

Major risk factors for necrotizing enterocolitis (NEC) are formula feeding and prematurity; however, their pathogenic mechanisms are unknown. Here, we found that insufficient arginine/nitric oxide synthesis limits blood flow in the intestinal microvasculature, leading to hypoxia, mucosal damage and NEC in the premature intestine after formula feeding. Formula feeding led to increased intestinal hypoxia in pups at postnatal day (P)1 and P5, but not in more mature pups at P9. Accordingly, blood flow in the intestinal microvasculature increased after formula feeding in P9 pups only. mRNA profiling revealed that regulators of arginine/nitric oxide synthesis are at higher levels in endothelial cells of the intestine in P9 than in P1 pups. Importantly, arginine supplementation increased intestinal microvasculature blood flow and prevented NEC, whereas an arginine antagonist exacerbated NEC. Our results suggest that balancing intestinal oxygen demand and supply in the premature intestine by modulating arginine/nitric oxide could be used to prevent NEC. This article has an associated First Person interview with the first author of the paper., Summary: We demonstrate that the immature gut is prone to necrotizing enterocolitis due to limited arginine/nitric oxide synthesis, leading to inadequate microcirculation in response to the challenge imposed by formula feeding.

Objective Heart disease risk can be programmed by intrauterine exposure to obesity. Dysregulating key transcription factors in cardiac progenitors can cause subsequent adult-onset heart disease. In this study, we investigated the transcriptional pathways that are altered in the embryonic heart and linked to heart disease risk in offspring exposed to obesity during pregnancy. Methods Female mice were fed an obesogenic diet and mated with males fed a control diet. Heart function and genome-wide gene expression were analyzed in adult offspring born to obese and lean mice at baseline and in response to stress. Cross-referencing with genes dysregulated genome-wide in cardiac progenitors from embryos of obese mice and human fetal hearts revealed the transcriptional events associated with adult-onset heart disease susceptibility. Results We found that adult mice born to obese mothers develop mild heart dysfunction consistent with early stages of disease. Accordingly, hearts of these mice dysregulated genes controlling extracellular matrix remodeling, metabolism, and TGF-β signaling, known to control heart disease progression. These pathways were already dysregulated in cardiac progenitors in embryos of obese mice. Moreover, in response to cardiovascular stress, the heart of adults born to obese dams developed exacerbated myocardial remodeling and excessively activated regulators of cell-extracellular matrix interactions but failed to activate metabolic regulators. Expression of developmentally regulated genes was altered in cardiac progenitors of embryos of obese mice and human hearts of fetuses of obese donors. Accordingly, the levels of Nkx2-5, a key regulator of heart development, inversely correlated with maternal body weight in mice. Furthermore, Nkx2-5 target genes were dysregulated in cardiac progenitors and persistently in adult hearts born to obese mice and human hearts from pregnancies affected by obesity. Conclusions Obesity during pregnancy alters Nkx2-5-controlled transcription in differentiating cardiac progenitors and persistently in the adult heart, making the adult heart vulnerable to dysregulated stress responses., Graphical abstract Image 1, Highlights • Maternal obesity programs progressive heart dysfunction in adult offspring. • Offspring of obese dams are prone to dysregulated stress responses in the heart. • Nkx2-5-controlled transcription is dysregulated in hearts exposed to obesity in utero. • Obesity during pregnancy broadly affects gene expression in the embryonic heart.

Despite the well-established cell-intrinsic role of epigenetic factors in normal and malignant hematopoiesis, their cell-extrinsic role remains largely unexplored. Herein we investigated the hematopoietic impact of inactivating Ezh2, a key component of polycomb repressive complex 2 (PRC2), in the fetal liver (FL) vascular niche. Hematopoietic specific (Vav-iCre) Ezh2 inactivation enhanced FL hematopoietic stem cell (HSC) expansion with normal FL erythropoiesis. In contrast, endothelium (Tie2-Cre) targeted Ezh2 inactivation resulted in embryonic lethality with severe anemia at embryonic day 13.5 despite normal emergence of functional HSCs. Ezh2-deficient FL endothelium overexpressed Mmp9, which cell-extrinsically depleted the membrane-bound form of Kit ligand (mKitL), an essential hematopoietic cytokine, in FL. Furthermore, Mmp9 inhibition in vitro restored mKitL expression along with the erythropoiesis supporting capacity of FL endothelial cells. These data establish that Ezh2 is intrinsically dispensable for FL HSCs and provides proof of principle that modulation of epigenetic regulators in niche components can exert a marked cell-extrinsic impact.

Isolation and culture of endothelial cells (ECs) is a useful tool to study the cellular processes involved in vascular development and vascular maturation. In this chapter, we describe a method to isolate and culture endothelial cells from placentae. This method takes advantage of two transgenes: ROSA26

The processes by which the intra-abdominal organ circulatory system develops in the embryo and during organogenesis are unclear. Previous studies have used fixed tissues to study the development of abdominal organ vasculature in the embryo; however, the intravital circulation of intra-abdominal organs in rodent fetal development has not been studied. This protocol describes a system that uses two-photon laser-scanning microscopy (TPLSM) for real-time observation and quantification of normal and pathologic live fetal intra-abdominal dynamics while the fetus is still connected to the mother via the umbilical cord.

Isolation and culture of endothelial cells (ECs) is a useful tool to study the cellular processes involved in vascular development and vascular maturation. In this chapter, we describe a method to isolate and culture endothelial cells from placentae. This method takes advantage of two transgenes: ROSA26 mT/mG , which drives the expression of GFP upon Cre-mediated recombination, and Tie2-Cre, which expresses Cre driven by the Tie2 promoter in endothelial progenitors and their descendants. GFP-expressing endothelial cells are isolated through fluorescence-activated cell sorting (FACS). The sorted cells express the endothelial marker CD31. This method can be used to study the morphological and physiological properties of placental endothelial cells in mice carrying mutations affecting vascular development.

The CCCTC-binding factor (CTCF) is a versatile transcriptional regulator required for embryogenesis, but its function in vascular development or in diseases with a vascular component is poorly understood. Here, we found that endothelial Ctcf is essential for mouse vascular development and limits accumulation of reactive oxygen species (ROS). Conditional knockout of Ctcf in endothelial progenitors and their descendants affected embryonic growth, and caused lethality at embryonic day 10.5 because of defective yolk sac and placental vascular development. Analysis of global gene expression revealed Frataxin (Fxn), the gene mutated in Friedreich's ataxia (FRDA), as the most strongly down-regulated gene in Ctcf-deficient placental endothelial cells. Moreover, in vitro reporter assays showed that Ctcf activates the Fxn promoter in endothelial cells. ROS are known to accumulate in the endothelium of FRDA patients. Importantly, Ctcf deficiency induced ROS-mediated DNA damage in endothelial cells in vitro, and in placental endothelium in vivo. Taken together, our findings indicate that Ctcf promotes vascular development and limits oxidative stress in endothelial cells. These results reveal a function for Ctcf in vascular development, and suggest a potential mechanism for endothelial dysfunction in FRDA.

The processes by which the intra-abdominal organ circulatory system develops in the embryo and during organogenesis are unclear. Previous studies have used fixed tissues to study the development of abdominal organ vasculature in the embryo; however, the intravital circulation of intra-abdominal organs in rodent fetal development has not been studied. This protocol describes a system that uses two-photon laser-scanning microscopy (TPLSM) for real-time observation and quantification of normal and pathologic live fetal intra-abdominal dynamics while the fetus is still connected to the mother via the umbilical cord.

Maternal separation (MS) in neonates can lead to intestinal injury. MS in neonatal mice disrupts mucosal morphology, induces colonic inflammation and increases trans-cellular permeability. Several studies indicate that intestinal epithelial stem cells are capable of initiating gut repair in a variety of injury models but have not been reported in MS. The pathophysiology of MS-induced gut injury and subsequent repair remains unclear, but communication between the brain and gut contribute to MS-induced colonic injury. Corticotropin-releasing hormone (CRH) is one of the mediators involved in the brain–gut axis response to MS-induced damage. We investigated the roles of the CRH receptors, CRHR1 and CRHR2, in MS-induced intestinal injury and subsequent repair. To distinguish their specific roles in mucosal injury, we selectively blocked CRHR1 and CRHR2 with pharmacological antagonists. Our results show that in response to MS, CRHR1 mediates gut injury by promoting intestinal inflammation, increasing gut permeability, altering intestinal morphology, and modulating the intestinal microbiota. In contrast, CRHR2 activates intestinal stem cells and is important for gut repair. Thus, selectively blocking CRHR1 and promoting CRHR2 activity could prevent the development of intestinal injuries and enhance repair in the neonatal period when there is increased risk of intestinal injury such as necrotizing enterocolitis.

Maintenance of vascular integrity is required for embryogenesis and organ homeostasis. However, the gene expression programs that stabilize blood vessels are poorly understood. Here, we show that the histone methyltransferase Ezh2 maintains integrity of the developing vasculature by repressing a transcriptional program that activates expression of Mmp9. Inactivation of Ezh2 in developing mouse endothelium caused embryonic lethality with compromised vascular integrity and increased extracellular matrix degradation. Genome-wide approaches showed that Ezh2 targets Mmp9 and its activators Fosl1 and Klf5. In addition, we uncovered Creb3l1 as an Ezh2 target that directly activates Mmp9 gene expression in the endothelium. Furthermore, genetic inactivation of Mmp9 rescued vascular integrity defects in Ezh2-deficient embryos. Thus, epigenetic repression of Creb3l1, Fosl1, Klf5 and Mmp9 by Ezh2 in endothelial cells maintains the integrity of the developing vasculature, potentially linking this transcriptional network to diseases with compromised vascular integrity.

The NOL1/NOP2/sun domain-containing genes encode the RNA methyltransferases Nsun2, 3, 4, 5, 6 and 7. Methylated RNA pervades the transcriptome, yet the function of RNA methyltransferases is poorly understood. Nsun2 and Nsun4 participate in cell proliferation and differentiation, protein biosynthesis and cancer. In addition, Nsun2 and Nsun7 dysfunction might cause intellectual disability and male sterility, respectively. The functions of Nsun3, Nsun5 and Nsun6 are unknown. Given the widespread distribution of RNA methylation, it is possible that Nsun genes participate in a broader range of relevant biological processes including the regulation of embryogenesis. Here, we describe the expression pattern of Nsun genes during mouse embryo development. In situ hybridization showed developmentally regulated Nsun gene expression. Nsun genes express broadly during gastrulation, but enrich in specific tissues as embryogenesis proceeds. Nsun transcripts enrich in the developing brain, consistent with proposed functions in neurocognitive development. In addition, Nsun transcripts enrich in the developing ear, eye, olfactory epithelium, branchial arches, heart and limb, suggesting possible overlapping functions of NSUN proteins in neural, craniofacial, cardiac, and limb morphogenesis. Furthermore, Nsun2 and Nsun6 enrich in the caudal neural tube and newly formed somites, suggesting possible functions in body axis extension. These results suggest possible overlapping functions of NSUN proteins and RNA methylation in broad aspects of embryonic development.

Defective fetoplacental vascular maturation causes intrauterine growth restriction (IUGR). A transcriptional switch initiates placental maturation, during which blood vessels elongate. However, the cellular mechanisms and regulatory pathways involved are unknown. We show that the histone methyltransferase G9a, also known as Ehmt2, activates the Notch pathway to promote placental vascular maturation. Placental vasculature from embryos with G9a-deficient endothelial progenitor cells failed to expand owing to decreased endothelial cell proliferation and increased trophoblast proliferation. Moreover, G9a deficiency altered the transcriptional switch initiating placental maturation and caused downregulation of Notch pathway effectors including

Defective fetoplacental vascular maturation causes intrauterine growth restriction (IUGR). A transcriptional switch initiates placental maturation where blood vessels elongate. However, cellular mechanisms and regulatory pathways involved are unknown. We show that the histone methyltransferase Ehmt2, also known as G9a, activates the Notch pathway to promote placental vascular maturation. Placental vasculature from embryos with G9a-deficient endothelial progenitor cells failed to expand due to decreased endothelial cell proliferation and increased trophoblast proliferation. Moreover, G9a deficiency altered the transcriptional switch initiating placental maturation and caused downregulation of Notch pathway effectors including Rbpj. Importantly, Notch pathway activation in G9a-deficient endothelial progenitors extended embryonic life and rescued placental vascular expansion. Thus, G9a activates the Notch pathway to balance endothelial cell and trophoblast proliferation and coordinates the transcriptional switch controlling placental vascular maturation. Accordingly, G9A and RBPJ were downregulated in human placentae from IUGR-affected pregnancies, suggesting that G9a is an important regulator in placental diseases caused by defective vascular maturation.

ErbB4 receptor tyrosine kinase contributes to the development of the heart, the central nervous system, and the lactating mammary gland, but whether it has a role in the development of the kidney epithelium is unknown. Here, we found that expression of Erbb4 isoforms JM-a CYT-1 and JM-a CYT-2 was first detectable around embryonic day 13 in the mouse, mainly in the collecting ducts and both the proximal and distal tubules. In vitro, overexpression of a relevant ErbB4 isoform promoted proliferation and disturbed polarization of kidney epithelial cells when cultured as three-dimensional structures. We examined ErbB4 function in developing kidney tubules in vivo with Pax8-Cre-mediated conditional overexpression of Rosa26 locus-targeted ERBB4 and with conditional Erbb4 knock-out mice. The Pax8-Cre-driven ERBB4 overexpression enhanced proliferation in the collecting ducts, reduced the size of epithelial duct lumens, and promoted formation of cortical tubular cysts. These defects were associated with changes in the subcellular distribution of markers of epithelial cell polarity. Similarly, the Pax8-Cre-mediated Erbb4 knock-out mice manifested dysfunctional kidneys with larger duct lumens and epithelial cell mispolarization. Taken together, these data suggest that ErbB4 signaling modulates proliferation and polarization, cellular functions critical for the development of epithelial ducts in the kidney.

The Crumbs family of transmembrane proteins has an important role in the differentiation of the apical membrane domain in various cell types, regulating such processes as epithelial cell polarization. The mammalian Crumbs protein family is composed of three members. Here, we inactivated the mouse Crb2 gene with gene-targeting techniques and found that the protein is crucial for early embryonic development with severe abnormalities appearing in Crb2-deficient embryos at late-gastrulation. Our findings indicate that the primary defect in the mutant embryos is disturbed polarity of the epiblast cells at the primitive streak, which affects epithelial to mesenchymal transition (EMT) during gastrulation, resulting in impaired mesoderm and endoderm formation, and embryonic lethality by embryonic day 12.5. These findings therefore indicate a novel role for the Crumbs family of proteins. Developmental Dynamics 240:2646–2656, 2011. © 2011 Wiley Periodicals, Inc.

The kidney is a classic model for studying mechanisms of inductive tissue interactions associated with the epithelial branching common to many embryonic organs, but the molecular mechanisms are still poorly known. Sprouty proteins antagonize tyrosine kinases in the Egf and Fgf receptors and are candidate components of inductive signalling in the kidney as well. We have addressed the function of sprouty proteins in vivo by targeted expression of human sprouty 2 ( SPRY2 ) in the ureteric bud, which normally expresses inductive signals and mouse sprouty 2 ( Spry2 ) . Ectopic SPRY2 expression led to postnatal death resulting from kidney failure, manifested as unilateral agenesis, lobularization of the organ or reduction in organ size because of inhibition of ureteric branching. The experimentally induced dysmorphology associated with deregulated expression of Wnt11 , Gdnf and Fgf7 genes in the early stages of organogenesis indicated a crucial role for sprouty function in coordination of epithelial-mesenchymal and stromal signalling, the sites of expression of these genes. Moreover, Fgf7 induced Spry2 gene expression in vitro and led with Gdnf to a partial rescue of the SPRY2 -mediated defect in ureteric branching. Remarkably, it also led to supernumerary epithelial bud formation from the Wolffian duct. Together, these data suggest that Spry genes contribute to reciprocal epithelial-mesenchymal and stromal signalling controlling ureteric branching, which involves the coordination of Ffg/Wnt11/Gdnf pathways.

In myasthenia gravis (MG) patients, the dysfunction of CD4(+)CD25(+) regulatory T cells (CD4(+)CD25(+) Tregs) may be one of the important pathogenesis of MG. Currently, the role of IFN-γ in autoimmune diseases is still controversial and needs further exploration. In this study, whether IFN-γ can induce CD4(+)CD25(-) T cells into CD4(+)CD25(+) Tregs in MG in vitro was investigated systematically.Flow cytometry was used to analyze the number of CD4(+)CD25(+) Tregs in MG patients and healthy controls (HCs). CD4(+)CD25(-) T cells were separated from the peripheral blood mononuclear cells of MG patients and HCs, and the CD4(+)CD25(+) Tregs were separated from HCs by Magnetic cell sorting (MACS). IFN-γ with different concentrations was used to stimulate CD4(+)CD25(-) T cells. The percentages of the induced CD4(+)CD25(+) T cells were detected by flow cytometry. The FoxP3 expression of the induced CD4(+)CD25(+) T cells in MG patients was detected by real-time PCR at mRNA level. The induced CD4(+)CD25(+) T cells were co-cultured with autologous CD4(+)CD25(-) T cells to estimate the suppressive ability of the induced CD4(+)CD25(+) T cells to CD4(+)CD25(-) T cells.It shows the percentages of CD4(+)CD25(+) T cells among CD4(+) T cells have no significant difference in MG patients compared with those in HCs. There is also merely no difference in the percentages of CD4(+)CD25(+) T cells between thymectomized and non-thymectomized MG patients. CD4(+)CD25(-) T cells can be induced to CD4(+)CD25(+) T cells after applying IFN-γ in MG patients and HCs. The proportion and FoxP3 expression of the induced CD4(+)CD25(+) T cells are the highest at the level of 40 ng/ml IFN-γ, and the suppressive function of the CD4(+)CD25(+) T cells induced by 40 ng/ml IFN-γ is the strongest in MG patients.This subject will further reveal the role of IFN-γ in the pathogenesis of MG from a new perspective. It will also provide the scientific basis for the clinical targeted therapy of MG.

Early maternal separation could lead to significant intestinal barrier and epithelial dysfunction. However, the exact mechanism remains to be elucidated and need to be investigated. Neonatal C57BL/6 mice were subjected to maternal separation: Maternal separation (MS) daily 3 h between postnatal day (PND) 5–9, single separation (SS) 3 h on PND 9 and no separation (NS). Colon and ileum permeability was measured by Ussing chamber. Severity of morphological changes in the colon was evaluated by blinded grading of histological stained sections. Trans-epithelial resistance of colon and ileum did not change indicating that the tissues remained intact during the course of the experiment. Permeability of trans-cellular tracer Horseradish peroxidase (HRP) was significantly increased in the colon of MS compared to SS and NS (p

Oxidative stress is implicated as an important factor in the development of Alzheimer's disease (AD). In the present study, we have investigated the effects of edaravone (9mg/kg, 3-methyl-1-phenyl-2-pyrazolin-5-one), a free radical scavenger, in a streptozotocin (STZ-3mg/kg) induced rat model of sporadic AD (sAD). Treatment with edaravone significantly improved STZ-induced cognitive damage as evaluated in Morris water maze and step-down tests and markedly restored changes in malondialdehyde (MDA), 4-hydroxy-2-nonenal (4-HNE) adducts, hydroxyl radical (OH), hydrogen peroxide (H2O2), total superoxide dismutase (T-SOD), reduced glutathione (GSH), glutathione peroxidase (GPx) and protein carbonyl (PC) levels. In addition, histomorphological observations confirmed the protective effect of edaravone on neuronal degeneration. Moreover, hyperphosphorylation of tau resulting from intracerebroventricular streptozotocin (ICV-STZ) injection was decreased by the administration of edaravone. These results provide experimental evidence demonstrating preventive effects of edaravone on cognitive dysfunction, oxidative stress and hyperphosphorylation of tau in ICV-STZ rats. Since edaravone has been used for treatment of patients with stroke, it represents a safe and established therapeutic intervention that has the potential for a novel application in the treatment of age-related neurodegenerative disorders associated with cognitive decline, such as AD.

Primary cilia are present in most vertebrate cells. They have complex structures that are required for signal transduction in developing tissues. The embryonic kidney consists of two major cell lineages, ureteric and metanephric mesenchyme. Here, we describe a method to isolate metanephric mesenchyme from ureteric bud, culture metanephric mesenchyme cells, and study primary cilia in cell culture.

Primary cilia are present in most vertebrate cells. They have complex structures that are required for signal transduction in developing tissues. The embryonic kidney consists of two major cell lineages, ureteric and metanephric mesenchyme. Here, we describe a method to isolate metanephric mesenchyme from ureteric bud, culture metanephric mesenchyme cells, and study primary cilia in cell culture.

Induction motor load will absorb more reactive power during power system fault, and large scale interconnected power system will front transient instability due to the lack of adequate dynamic VAR supporting. This paper focuses on a detailed discussion of the induction motor load as it pertains to voltage stability studies. Meanwhile, a comparative study on the transient support ability of SVC and Cascade STATCOM has been made, and the main factors influencing the ability have also been in-depth discussed. The system simulation model is built in the MATLAB/Simulink environment using the PSB, and the results indicate that the Cascaded STATCOM has better transient support ability than SVC during power system fault, and validate that the instantaneous current single-phase control strategy can ensure Cascade STATCOM continuously operating even under asymmetric fault without over-currents. (7 pages)

The mammalian kidney and male reproductive system are both derived from the intermediate mesoderm. The spatial and temporal expression of bone morphogenetic protein (BMP) 2 and BMP4 and their cognate receptor, activin like kinase 3 (ALK3), suggests a functional role for BMP-ALK3 signaling during formation of intermediate mesoderm-derivative organs. Here, we define cell autonomous functions for Alk3 in the kidney and male gonad in mice with CRE-mediated Alk3 inactivation targeted to intermediate mesoderm progenitors (Alk3IMP null). Alk3-deficient mice exhibit simple renal hypoplasia characterized by decreases in both kidney size and nephron number but normal tissue architecture. These defects are preceded by a decreased contribution of Alk3-deleted cells to the metanephric blastema and reduced expression of Osr1 and SIX2, which mark nephron progenitor cells. Mutant mice are also characterized by defects in intermediate mesoderm-derived genital tissues with fewer mesonephric tubules and testicular Leydig cells, epithelial vacuolization in the postnatal corpus epididymis, and decreased serum testosterone levels and reduced fertility. Analysis of ALK3-dependent signaling effectors revealed lineage-specific reduction of phospho-p38 MAPK in metanephric mesenchyme and phospho-SMAD1/5/8 in the testis. Together, these results demonstrate a requirement for Alk3 in distinct progenitor cell populations derived from the intermediate mesoderm.