bluuebunny/crossref_metadata_2025 huggingface dataset:
Superrotation of Earth’s Inner Core, Extraterrestrial Impacts, and the Effective Viscosity of Outer Core
Authors: Mohazzabi Pirooz , Skalbeck John D.
Published: May 2015

The recently verified superrotation of Earth’s inner core is examined and a new model is presented which is based on the tidal despinning of the mantle and the viscosity of the outer core. The model also takes into account other damping mechanisms arising from the inner core superrotation such as magnetic and gravitational coupling as well as contribution from eddy viscosity in the outer core. The effective viscosity obtained in this model confirms a previously well constrained value of about 103 Pa s. In addition, the model shows that the currently measured superrotation of the inner core must be almost exactly equal to its asymptotic or steady-state value. The effect of extraterrestrial impacts is also investigated, and it is shown that perturbations due to such impacts can only persist over a short geological time.
Genetic and Environmental Influences on Retinopathy of Prematurity
Authors: Ortega-Molina J. M. , Anaya-Alaminos R. , Uberos-Fernández J. , Solans-Pérez de Larraya A. , Chaves-Samaniego M. J. , Salgado-Miranda A. , Piñar-Molina R. , Jerez-Calero A. , García-Serrano J. L.
Published: May 2015

Objective. The goals were to isolate and study the genetic susceptibility to retinopathy of prematurity (ROP), as well as the gene‐environment interaction established in this disease. Methods. A retrospective study (2000–2014) was performed about the heritability of retinopathy of prematurity in 257 infants who were born at a gestational age of ≤32 weeks. The ROP was studied and treated by a single pediatric ophthalmologist. A binary logistic regression analysis was completed between the presence or absence of ROP and the predictor variables. Results. Data obtained from 38 monozygotic twins, 66 dizygotic twins, and 153 of simple birth were analyzed. The clinical features of the cohorts of monozygotic and dizygotic twins were not significantly different. Genetic factors represented 72.8% of the variability in the stage of ROP, environmental factors 23.08%, and random factors 4.12%. The environmental variables representing the highest risk of ROP were the number of days of tracheal intubation (p < 0.001), postnatal weight gain (p = 0.001), and development of sepsis (p = 0.0014). Conclusion. The heritability of ROP was found to be 0.73. The environmental factors regulate and modify the expression of the genetic code.
Genome-Wide Gene Expression in relation to Age in Large Laboratory Cohorts ofDrosophila melanogaster
Authors: Carlson Kimberly A. , Gardner Kylee , Pashaj Anjeza , Carlson Darby J. , Yu Fang , Eudy James D. , Zhang Chi , Harshman Lawrence G.
Published: May 2015

Aging is a complex process characterized by a steady decline in an organism’s ability to perform life-sustaining tasks. In the present study, two cages of approximately 12,000 matedDrosophila melanogasterfemales were used as a source of RNA from individuals sampled frequently as a function of age. A linear model for microarray data method was used for the microarray analysis to adjust for the box effect; it identified 1,581 candidate aging genes. Cluster analyses using a self-organizing map algorithm on the 1,581 significant genes identified gene expression patterns across different ages. Genes involved in immune system function and regulation, chorion assembly and function, and metabolism were all significantly differentially expressed as a function of age. The temporal pattern of data indicated that gene expression related to aging is affected relatively early in life span. In addition, the temporal variance in gene expression in immune function genes was compared to a random set of genes. There was an increase in the variance of gene expression within each cohort, which was not observed in the set of random genes. This observation is compatible with the hypothesis thatD. melanogasterimmune function genes lose control of gene expression as flies age.
Unusual Bilateral Paramolars Associated with Clinical Complications
Authors: Sulabha A. N. , Sameer C.
Published: May 2015

Paramolars are rare supernumerary structures of maxillofacial complex that occur buccally or lingually near the molar row. Predominantly these occur singly; bilateral presentation is very rare. This paper reports two unusual bilateral presentations of paramolars with clinical complication and its management. One of the cases in the present paper also documents the cooccurrence of bilateral paramolars and microdontia of single tooth and one of its paramolars presented with multilobed crown with an anomalous buccal tubercle.
A Case Report of Implant Fracture of Extensively Porous-Coated, Distally Fixated Cementless Long Stem: Detailed Course of Stem Bending Development
Authors: Mimura Tomohiro
Published: May 2015

We report the fracture of a cementless long stem in a distally fixated, extensively porous-coated femoral prosthesis used for revisional total hip arthroplasty (THA) 9 years previously in a 48-year-old woman, measuring 58 kg in weight and 155 cm in height. Following resolution of an infection 7 years after the revisional THA, a series of posterior dislocations occurred up until 7 months before sudden stem fracture. Extensive radiographic imaging evidence indicated a gradual progression of bending in the stem, and scanning electron microscope energy dispersive X-ray spectroscopy revealed oxygen in the medial and lateral sections, suspecting in vivo corrosion. We retrospectively examined the detailed course of stem bending development prior to stem fracture. The stem bending immediately after the revisional THA, at the first dislocation, and immediately before the stem fracture was 0°, 1.9°, and 5.2°, respectively. We consider that the cyclic loading with poor proximal bone support, distal fixation, and small diameter were the potential risk of this implant fracture. However, the course of stem bending development suggested that repeated operations and several dislocations might have aggravated the implant fatigue in the present case.
Liver Failure Impairs the Intrahepatic Elimination of Interleukin-6, Tumor Necrosis Factor-Alpha, Hepatocyte Growth Factor, and Transforming Growth Factor-Beta
Authors: Porowski Dawid , Wirkowska Agnieszka , Hryniewiecka Ewa , Wyzgał Janusz , Pacholczyk Marek , Pączek Leszek
Published: May 2015

The strategic location of the liver and its metabolic activity make it a key organ regulating homeostasis. Our purpose was to examine its participation in removal of cytokines: interleukin-6 (Il-6), tumor necrosis factor-alpha (TNF-α), hepatocyte growth factor (HGF), and transforming growth factor-beta (TGF-β) from the portal circulation in human. 20 liver donors and 20 patients with end-stage liver failure were included in the study. Their blood was collected during liver transplantation from the portal, hepatic, and peripheral vein, and the hepatic artery and cytokines’ concentrations were determined. Using the results the mathematical model of cytokine elimination by the liver was developed. In donors significantly lower levels of IL-6, TNF-α, HGF, and TGF-βwere detected in portal blood compared to hepatic vein. In patients with cirrhosis there were no significant differences of IL-6, TNF-α, and TGF-βlevels between portal and hepatic veins. Significantly higher level of HGF in hepatic compared to portal vein was observed. In healthy liver elimination of the cytokines prevailed over their synthesis, as reflected by the positive values of the elimination ratios. In the cirrhotic liver elimination ratios of Il-6, HGF, and TGF-βwere negative indicating the prevalence of intrahepatic synthesis of cytokines over their removal.
Nonlinear Stability Analysis of a Composite Girder Cable-Stayed Bridge with Three Pylons during Construction
Authors: Deng Xiaoguang , Liu Muyu
Published: May 2015

Based on the nonlinear stability analysis method, the 3D nonlinear finite element model of a composite girder cable-stayed bridge with three pylons is established to research the effect of factors including geometric nonlinearity, material nonlinearity, static wind load, and unbalanced construction load on the structural stability during construction. Besides, the structural nonlinear stability in different construction schemes and the determination of temporary pier position are also studied. The nonlinear stability safety factors are calculated to demonstrate the rationality and safety of construction schemes. The results show that the nonlinear stability safety factors of this bridge during construction meet the design requirement and the minimum value occurs in the maximum double cantilever stage. Besides, the nonlinear stability of the structure in the side of edge-pylon meets the design requirement in the two construction schemes. Furthermore, the temporary pier can improve the structure stability, effectively, and the actual position is reasonable. In addition, the local buckling of steel girder occurs earlier than overall instability under load in some cable tension stages. Finally, static wind load and the unbalanced construction load should be considered in the stability analysis for the adverse impact.
Improved Thrombin Hemostat Using the Cross-Linked Gelatin by Microbial Transglutaminase
Authors: Yu Tengfei , Guan Yuepeng , Xie Xia , Huang Yaqin , Tang Jie
Published: May 2015

It is well known that the thrombin obtained from animal is available in clinical treatment, which plays an important role in hemostasis and the treatment of hemorrhagic diseases. However, how to achieve complete hemostasis in 2 min is still a challenge. In this report, the thrombin hemostatic has been improved using the cross-linked gelatin by microbial transglutaminase, and its efficacy was demonstrated by the vitro experiment. Compared with the traditional thrombin hemostatic the clotting time with the improved hemostat is significantly shorter. It may rapidly stop blood loss, which would provide a simple, safe, and cost-effective surgical sealant.
The PI3K/Akt Pathway Regulates Oxygen Metabolism via Pyruvate Dehydrogenase (PDH)-E1α Phosphorylation
Authors: Cerniglia George J. , Dey Souvik , Gallagher-Colombo Shannon M. , Daurio Natalie A. , Tuttle Stephen , Busch Theresa M. , Lin Alexander , Sun Ramon , Esipova Tatiana V. , Vinogradov Sergei A. , Denko Nicholas , Koumenis Constantinos , Maity Amit
Published: May 2015

Inhibition of the PI3K/Akt pathway decreases hypoxia within SQ20B human head and neck cancer xenografts. We set out to understand the molecular mechanism underlying this observation. We measured oxygen consumption using both a Clark electrode and an extracellular flux analyzer. We made these measurements after various pharmacologic and genetic manipulations. Pharmacologic inhibition of the PI3K/mTOR pathway or genetic inhibition of Akt/PI3K decreased the oxygen consumption rate (OCR) in vitro in SQ20B and other cell lines by 30% to 40%. Pharmacologic inhibition of this pathway increased phosphorylation of the E1α subunit of the pyruvate dehydrogenase (PDH) complex on Ser293, which inhibits activity of this critical gatekeeper of mitochondrial respiration. Expressing wild-type PTEN in a doxycycline-inducible manner in a cell line with mutant PTEN led to an increase in PDH-E1α phosphorylation and a decrease in OCR. Pretreatment of SQ20B cells with dichloroacetate (DCA), which inhibits PDH-E1α phosphorylation by inhibiting dehydrogenase kinases (PDK), reversed the decrease in OCR in response to PI3K/Akt/mTOR inhibition. Likewise, introduction of exogenous PDH-E1α that contains serine to alanine mutations, which can no longer be regulated by phosphorylation, also blunted the decrease in OCR seen with PI3K/mTOR inhibition. Our findings highlight an association between the PI3K/mTOR pathway and tumor cell oxygen consumption that is regulated in part by PDH phosphorylation. These results have important implications for understanding the effects of PI3K pathway activation in tumor metabolism and also in designing cancer therapy trials that use inhibitors of this pathway. Mol Cancer Ther; 14(8); 1928–38. ©2015 AACR.
Pre-Eclampsia-Associated Reduction in Placental Growth Factor Impaired Beta Cell Proliferation Through PI3k Signalling
Authors: Li Jun , Ying Huanchun , Cai Guiyang , Guo Quan , Chen Lizhu
Published: May 2015

Background/Aim: Reduction in serum placental growth factor (PLGF) frequently co-occurs with preeclampsia (PE) and gestational diabetes mellitus (GDM). Recently, we reported that impairment in gestational beta-cell mass growth may result from PE-associated reduction in PLGF and lead to development of GDM. Here, we studied the underlying mechanisms. Methods: We co-cultured primary mouse beta cells with mouse islet endothelial cells (MS1), with or without PLGF. We also cultured beta cells in conditioned media from PLGF-treated MS1. Specific signal-pathway inhibitors were applied to cultured beta cells in conditioned media from PLGF-treated MS1. We analysed beta-cell proliferation by BrdU incorporation. We analysed changes in cell number by a MTT assay. We analysed protein levels of cell-cycle regulators in beta cells by Western blot. Results: PLGF itself failed to induce beta-cell proliferation, but significantly augmented proliferation of beta cells co-cultured with MS1, which resulted in significant increases in cell number. Conditioned media from the PLGF-treated MS1 cells similarly induced beta-cell proliferation, which was abolished by inhibition of PI3k/Akt signalling, but not by inhibition of either ERK/MAPK or JNK signalling. The induction of beta-cell proliferation by PLGF-treated MS1 cells appeared to involve decreases in cell-cycle inhibitors p21 and p27, and increases in cell-cycle activators CDK4 and CyclinD1. Conclusion: Gestational PLGF may target islet endothelial cells to release growth factors that activate PI3k/Akt signalling in beta cells to increase their proliferation. PE-associated reduction in PLGF impairs these processes to result in GDM.
Integrin β1, Osmosensing, and Chemoresistance in Mouse Ehrlich Carcinoma Cells
Authors: Sørensen Belinda Halling , Rasmussen Line Jee Hartmann , Broberg Bjørn Sindballe , Klausen Thomas Kjær , Sauter Daniel Peter Rafael , Lambert Ian Henry , Aspberg Anders , Hoffmann Else Kay
Published: May 2015

Background/Aims: Altered expression of the integrin family of cell adhesion receptors has been associated with initiation, progression, and metastasis of solid tumors as well as in the development of chemoresistance. Here, we investigated the role of integrins, in particular integrin β1, in cell volume regulation and drug-induced apoptosis in adherent and non-adherent Ehrlich ascites cell lines. Methods: Adhesion phenotypes were verified by colorimetric cell-adhesion-assay. Quantitative real-time PCR and western blot were used to compare expression levels of integrin subunits. Small interfering RNA was used to silence integrin β1 expression. Regulatory volume decrease (RVD) after cell swelling was studied with calcein-fluorescence-self-quenching and Coulter counter analysis. Taurine efflux was estimated with tracer technique. Caspase assay was used to determine apoptosis. Results: We show that adherent cells have stronger fibronectin binding and a significantly increased expression of integrin α5, αv, and β1 at mRNA and protein level, compared to non-adherent cells. Knockdown of integrin β1 reduced RVD of the adherent but not of the non-adherent cells. Efflux of taurine was unaffected. In contrast to non-adherent, adherent cells exhibited chemoresistance to chemotherapeutic drugs (cisplatin and gemcitabine). However, knockdown of integrin β1 promoted cisplatin-induced caspase activity in adherent cells. Conclusion: Our data identifies integrin β1 as a part of the osmosensing machinery and regulator of cisplatin resistance in adherent Ehrlich cells.
p38MAPK Signaling Enhances Glycolysis Through the Up-Regulation of the Glucose Transporter GLUT-4 in Gastric Cancer Cells
Authors: Liu Jingjing , Wen Dacheng , Fang Xuedong , Wang Xudong , Liu Tianzhou , Zhu Jiaming
Published: May 2015

Background/Aims: Previous studies have shown that p38MAPK is involved in gastric cancer, yet the underlying mechanism remains unclear. Methods: q-PCR, Western blot and immunohistochemistry were used to explore the expression of PP2A and the phosphorylation of p38MAPK in gastric cancer tissues and normal gastric tissues. Activated p38MAPK in the gastric cancer cell line MKN45 using activator, then q-PCR, glucose uptake assay and colony formation assay were performed to determine whether p38MAPK promotes gastric cancer through the enhancement of glycolysis. After transfection of p38MAPK dominant negative mutation (p38DN) into MKN45 cells or MKN45 cells treated with an inhibitor of p38MAPK, Western blot was performed to detect the expression of GLUT-4. The knock down of MEF2α in MKN45 cells by siRNA was followed by Western blot and luciferase reporter assay to investigate the underlying mechanism of the role of p38MAPK in the promotion of gastric cancer. Finally, q-PCR, Western blot and immunohistochemistry were performed to examine GLUT-4 expression in gastric cancer tissues and normal gastric tissues. Results: We found that p38MAPK activation significantly increases GLUT-4 expression and promotes glucose uptake and cell growth in gastric cancer cells. Inhibition of p38MAPK abrogates the up-regulation of GLUT-4. MEF2α knockdown abolishes p38MAPK-mediated GLUT-4 up-regulation. PP2A, an inhibitor of p38MAPK, is down-regulated in gastric cancer tissues, which might contribute to the activation of p38MAPK. Conclusions: Our data indicate that the abnormal activation of p38MAPK promotes glycolysis within gastric cancer cells through the upregulation of GLUT-4 in a MEF2a-dependent manner.
MiR-31 Downregulation Protects Against Cardiac Ischemia/Reperfusion Injury by Targeting Protein Kinase C Epsilon (PKCe) Directly
Authors: Wang Yongyi , Men Min , Yang Wengang , Zheng Hui , Xue Song
Published: May 2015

Background: Various miRNAs have been shown to participate in cardiac ischemia/reperfusion injury (I/R). miR-31 was identified as the most strikingly upregulated miRNA after acute myocardial infarction; therefore, the underlying role and mechanism of miR-31 in cardiac I/R was investigated. Methods: miR-31 expression was detected after cardiac I/R in mice. The cardioprotective effect of miR-31 downregulation was assessed in vitro and in vivo. The functional target gene and its downstream molecule were determined. Results: miR-31 expression increased after I/R. miR-31 downregulation increased cell viability and SOD activity and decreased LDH activity and MDA content in vitro. Additionally, miR-31 downregulation alleviated myocardial infarct size in vivo. PKCe was identified as the functional target gene of miR-31, and NFκB was identified as its downstream molecule that was involved in the miR-31-mediated cardioprotective effect. Conclusion: miR-31 expression increased throughout the cardiac I/R process, and miR-31 downregulation induced a cardioprotective effect via a miR-31/PKCe/NFκB-dependent pathway.
Tetramethylpyrazine Ameliorated Hypoxia-Induced Myocardial Cell Apoptosis via HIF-1α/JNK/p38 and IGFBP3/BNIP3 Inhibition to Upregulate PI3K/Akt Survival Signaling
Authors: Lin Kuan-Ho , Kuo Wei-Wen , Jiang Ai-Zhi , Pai Peiying , Lin Jing-Ying , Chen Wei-Kung , Day Cecilia Hsuan , Shen Chia-Yao , Padma V. Vijaya , Huang Chih Yang
Published: May 2015

Background: Hemorrhagic shock (HS) is the major cause of death from trauma. Hemorrhagic shock may lead to cellular hypoxia and organ damage. Our previous findings showed that HS induced a cardiac apoptosis pathway and synergistically caused myocardial cell damage in diabetic rats under trauma-induced HS. Tetramethylpyrazine (TMP) is a major biologically active ingredient purified from the rhizome of Ligusticum wallichii (called Chuang Xiong in Chinese). Chuan Xiong rescued cells from synergistic cardiomyoblast cell injury under high-glucose (HG) conditions plus hypoxia. TMP is one of the most important active ingredients that elevated the survival rate in ischemic brain injury and prevented inducible NO synthase expression to have anti-inflammatory effects against cell damage in different cell types. Method: Here, we further investigate whether TMP can protect against hypoxic (<1% oxygen) conditions in H9c2 cardiomyoblast cells for 24 hrs. Results: Our results showed that hypoxia mediated through HIF-1α/JNK/p38 activation significantly elevated the levels of the hypoxia-related proteins HIF-1α, BNIP3 and IGFBP3, further enhanced the pro-apoptotic protein Bak and upregulated downstream Caspase 9 and 3, resulting in cell death. All of these phenomena were fully recovered under TMP treatment. We observed that TMP exerted this effect by activating the IGF1 receptor survival pathway, dependent primarily on PI3K/Akt. When PI3K (class I) was blocked by specific siRNA, the hypoxia-induced activated caspase 3 and cell apoptosis could not be reversed by TMP treatment. Conclusion: Our results strongly suggest that TMP could be used to restore hypoxia-induced myocardial cell apoptosis and cardiac hypoxic damage.
Role of Microglia in Autism: Recent Advances
Authors: Takano Tomoyuki
Published: May 2015

The neurobiological basis for autism remains poorly understood. However, the neuroinflammation processes play an important role in the induction of autistic behavioral changes. Microglial cells can exhibit widely differing functions during brain development, including synaptogenesis and stem cell proliferation, in addition to playing a role in the innate immunity. Mounting evidence indicates that microglial activation or dysfunction can profoundly affect neural development, resulting in neurodevelopmental disorders, including autism. These mechanisms in autism have been investigated using neuropathological studies of human autopsy brains, a large number of murine experimental models and in vivo neuroimaging studies of the human brain. The purpose of this review is to discuss microglial activation or dysfunction and to highlight the detrimental role that microglia play in the development of autism. The recent advances presented in this review support that further elucidation of the mechanisms and kinetics of microglial responses will help to establish a window for therapeutic intervention in individuals with autism.
Assessment of the HNF1B Score as a Tool to Select Patients for HNF1B Genetic Testing
Authors: Clissold Rhian , Shields Beverley , Ellard Sian , Hattersley Andrew , Bingham Coralie
Published: May 2015

Background/Aims: Diagnosing hepatocyte nuclear factor 1β (HNF1B)-related disease is a challenging task due to the phenotypic variability and frequent absence of a family history. An HNF1B score has recently been developed to help select appropriate patients for genetic testing with a negative predictive value (NPV) of 99%. We aimed at testing the clinical utility of this score in a large number of referrals for HNF1B genetic testing to the UK diagnostic testing service for the HNF1B gene. Methods: An HNF1B score was assigned for 686 UK referrals for HNF1B genetic testing using clinical information available at referral. The performance of the score was evaluated by receiver-operating characteristic curve analysis. The relative discriminatory ability of different clinical features for making a genetic diagnosis of HNF1B-related disease were estimated in the UK dataset alone and pooled with French data. Results: The HNF1B score discriminated between patients with and without a mutation reasonably well with an area under the curve of 0.72. Applying the suggested cut-off score of ≥8 gave a NPV of 85%. In a pooled analysis, antenatal renal abnormalities, renal hyperechogenicity and cysts were discriminatory in children, whereas renal hypoplasia and cysts were discriminatory in adults. Pancreatic abnormalities were discriminatory in both, whereas other extra-renal characteristics had a large effect size only in adults. Conclusion: The HNF1B score was discriminatory for HNF1B mutations in a large cohort of individuals tested in a single UK centre. The lower NPV (85 vs. 99%) reduces its clinical utility in selecting patients for HNF1B genetic testing, although validation in a prospective cohort is required.
Curcumin Protects -SH Groups and Sulphate Transport after Oxidative Damage in Human Erythrocytes
Authors: Morabito Rossana , Falliti Giuseppe , Geraci Antonella , Spada Giuseppa La , Marino Angela
Published: May 2015

Background/Aims: Erythrocytes, continuously exposed to oxygen pressure and toxic compounds, are sensitive to oxidative stress, namely acting on integral Band 3 protein, with consequences on cell membranes deformability and anion transport efficiency. The aim of the present investigation, conducted on human erythrocytes, is to verify whether curcumin (1 or 10µM), a natural compound with proved antioxidant properties, may counteract Band 3-mediated anion transport alterations due to oxidative stress. Methods: Oxidative conditions were induced by exposure to, alternatively, either 2 mM N-ethylmaleimide (NEM) or pH-modified solutions (6.5 and 8.5). Rate constant for SO4= uptake and -SH groups estimation were measured to verify the effect of oxidative stress on anion transport efficiency and erythrocyte membranes. Results: After the exposure of erythrocytes to, alternatively, NEM or pH-modified solutions, a significant decrease in both rate constant for SO4= uptake and -SH groups was observed, which was prevented by curcumin, with a dose-dependent effect. Conclusions: Our results show that: i) the decreased efficiency of anion transport may be due to changes in Band 3 protein structure caused by cysteine -SH groups oxidation, especially after exposure to NEM and pH 6.5; ii) 10 µM Curcumin is effective in protecting erythrocytes from oxidative stress events at level of cell membrane transport.
Protein Phosphatase 1 Beta is Modulated by Chronic Hypoxia and Involved in the Angiogenic Endothelial Cell Migration
Authors: Iacobazzi Dominga , Garaeva Indira , Albertario Ambra , Cherif Myriam , Angelini Gianni D. , Caputo Massimo , Ghorbel Mohamed T.
Published: May 2015

Background/Aim: Endothelial cell migration is required for physiological angiogenesis, but also contributes to various pathological conditions, including tumour vascularization. The mRNA expression of PP1cβ, the beta isoform of the catalytic PP1 subunit, was shown to be upregulated in chronic hypoxia. Since hypoxia is a major regulator of angiogenesis, the potential role of PP1cβ in angiogenesis was investigated. Methods: We examined PP1cβ protein level in pediatric heart following chronic hypoxia and found PP1cβ upregulation in cyanotic compared with acyanotic myocardium. By treating HUVEC cells with hypoxia mimicking agent, PP1cβ protein level increased with maximum at 8 hours. The effect of PP1cβ pharmacological inhibition, knockdown and overexpression, on endothelial cell migration and morphogenesis, was examined using in vitro wound healing scratch assay and endothelial tube formation assay. The PP1cβ knockdown effects on F-actin reorganization (phalloidin staining), focal adhesion formation (vinculin) and focal adhesion kinases (FAK) activation, were evaluated by immunocytochemical staining and immunoblotting with specific antibodies. Results: PP1cβ knockdown significantly reduces endothelial cell migration, but does not have any significant effect on endothelial tube formation. Endothelial cell migration in the knockdown group is restored to the control level upon consecutive transfection with PP1cβ cDNA. PP1cβ overexpression does not significantly affect endothelial cell migration. Furthermore, PP1cβ knockdown induces profound cytoskeletal reorganization, loss of focal adhesion sites and impairment of focal adhesion kinases (FAK) activation. Conclusions: PP1cβ is regulator of endothelial cell migration, which is critical in the angiogenic process. PP1cβ inhibition reduces endothelial cell migration through focal adhesion turnover and actin polymerization pathways.
Antidiabetic Effect of Salvianolic Acid A on Diabetic Animal Models via AMPK Activation and Mitochondrial Regulation
Authors: Qiang Guifen , Yang Xiuying , Shi Lili , Zhang Hengai , Chen Bainian , Zhao Yan , Zu Mian , Zhou Dan , Guo Jing , Yang Haiguang , Zhang Li , Du Guanhua
Published: May 2015

Background/Aims: Diabetes mellitus (DM) characterized by hyperglycemia contributes to macrovascular and microvascular complications. Salvianolic acid A (SalA) is a polyphenolic compound isolated from the root of Salvia miltiorrhiza Bunge, which is a traditional Chinese medicine widely used to treat cardiovascular diseases. However, little is known about its antidiabetic effect. Our study aimed to investigate the in vivo and in vitro antidiabetic effect of SalA and the underlying mechanisms. Methods: Alloxan-induced type 1 diabetic mice and high-fat diet (HFD) and low-dose streptozotocin (STZ)-induced type 2 diabetic rats received SalA treatment. Blood glucose, oral glucose tolerance test (OGTT), 24-h food and water intake were monitored. In vitro, glucose consumption and uptake were measured in HepG2 cells and L6 myotubes. Mitochondrial function was detected in hepatic and skeletal muscle mitochondria. AMP-activated protein kinase (AMPK) and Akt were analyzed by western blot. Results: In both type 1 and type 2 diabetic animals, SalA lowered fasting blood glucose (FBG) and fed blood glucose in dose-dependent manner, as well as reduced 24-h food and water intake. In vitro, SalA caused dose-dependent increase in glucose consumption and enhanced glucose uptake. SalA significantly increased ATP production from 10 min to 12 h in HepG2 cells and L6 myotubes. Interestingly, SalA decreased mitochondrial membrane potential (MMP) in HepG2 cells. Furthermore, SalA improved hepatic and skeletal muscle mitochondrial function, increased ATP production, and concurrently decreased MMP. In particularly, SalA activated AMPK phosphorylation through Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ)/AMPK signaling pathway, independent of liver kinase 1 (LKB1)/AMPK pathway. However, SalA didn't show any effect on insulin secretagogue and activation of PI3K/Akt signaling pathway. Conclusion: SalA exhibits the antidiabetic effects in diabetic animal models through improving mitochondrial function, increasing ATP production, and decreasing MMP via CaMKKβ/AMPK signaling pathway.
Alternation of histone and DNA methylation in human atherosclerotic carotid plaques
Authors: Napieralski Rudolf , Wagner Ernst , Gebhard Harry , Schmitt Manfred , Zimmermann Alexander , Eckstein Hans-Henning , Greißel Anna , Culmes Mihaela , Zernecke Alma , Pelisek Jaroslav
Published: May 2015

Little is known about epigenetics and its possible role in atherosclerosis. We here analysed histone and DNA methylation and the expression of corresponding methyltransferases in early and advanced human atherosclerotic carotid lesions in comparison to healthy carotid arteries. Western Blotting was performed on carotid plaques from our biobank with early (n=60) or advanced (n=60) stages of atherosclerosis and healthy carotid arteries (n=12) to analyse di-methylation patterns of histone H3 at positions K4, K9 and K27. In atherosclerotic lesions, di-methylation of H3K4 was unaltered and that of H3K9 and H3K27 significantly decreased compared to control arteries. Immunohistochemistry revealed an increased appearance of di-methylated H3K4 in smooth muscle cells (SMCs), a decreased expression of di-methylated H3K9 in SMCs and inflammatory cells, and reduced di-methylated H3K27 in inflammatory cells in advanced versus early atherosclerosis. Expression of corresponding histone methyltransferases MLL2 and G9a was increased in advanced versus early atherosclerosis. Genomic DNA hypomethylation, as determined by PCR for methylated LINE1 and SAT-alpha, was observed in early and advanced plaques compared to control arteries and in cell-free serum of patients with high-grade carotid stenosis compared to healthy volunteers. In contrast, no differences in DNA methylation were observed in blood cells. Expression of DNA-methyltransferase DNMT1 was reduced in atherosclerotic plaques versus controls, DNMT3A was undetectable, and DNMT3B not altered. DNA-demethylase TET1 was increased in atherosclerosisc plaques. The extent of histone and DNA methylation and expression of some corresponding methyltransferases are significantly altered in atherosclerosis, suggesting a possible contribution of epigenetics in disease development.
Microvesicles from platelets: novel drivers of vascular inflammation
Authors: Vajen Tanja , Mause Sebastian , Koenen Rory
Published: May 2015

Microvesicles are receiving increased attention not only as biomarkers but also as mediators of cell communication and as integral effectors of disease. Platelets present a major source of microvesicles and release these microvesicles either spontaneously or upon activation. Platelet-derived microvesicles retain many features of their parent cells and have been shown to exert modulatory effects on vascular and immune cells. Accordingly, microvesicles from platelets can be measured at increased levels in patients with cardiovascular disease or individuals at risk. In addition, isolated microvesicles from platelets were shown to exert immunomodulatory actions on various cell types. In this review the various aspects of platelet-derived microvesicles including release, clearance, measurement, occurrence during disease and relevance for the pathophysiology of vascular inflammation will be discussed.
The impact of selectins on mortality in stable carotid atherosclerosis
Authors: Hoke Matthias , Winter Max-Paul , Wagner Oswald , Exner Markus , Schillinger Martin , Arnold Zsuzsanna , Mlekusch Wolfgang , Maurer Gerald , Koppensteiner Renate , Minar Erich , Goliasch Georg
Published: May 2015

Cellular adhesion molecules also known as selectins promote recruitment of inflammatory cells into the arterial wall where they interact with lipid particles leading subsequently to plaque formation. The intercellular adhesion molecule-1 (ICAM-1), the vascular cell adhesion molecule-1 (VCAM-1) and the endothelial-leukocyte adhesion molecule 1 (ELAM-1) also known as E-selectin mediate the attachment of leukocytes and have been implicated in the destabilisation of atherosclerotic plaques. Therefore, we hypothesised that plasma selectin levels are associated with adverse clinical outcome. We prospectively studied 855 patients with sonographically confirmed carotid atherosclerosis. During a median follow-up of 6.2 years, corresponding to 5,551 overall person-years, 275 patients (26 %) died. We detected a significant association between cardiovascular mortality and ICAM-1 (adjusted hazard ratio [HR]: 3.43, 95 % confidence interval [CI] 2.00–5.88, p< 0.001) as well as VCAM-1 (adjusted HR: 2.51, 95 % CI 1.45–4.34, p=0.001) when comparing the fourth with the first quartile. Comparable results were obtained for all-cause mortality. In contrast, we could not detect a significant association between E-selectin and all-cause or cardiovascular mortality. We identified the selectins ICAM-1 and VCAM-1 as strong and independent predictors of all-cause and cardiovascular mortality in patients with stable carotid atherosclerosis. These molecules are elevated in states of endothelial activation and might assist to monitor anti-atherosclerotic therapy and select those patients with carotid atherosclerosis, who are at higher risk for cardiovascular events.
D-dimer for prediction of long-term outcome in cryptogenic stroke patients with patent foramen ovale
Authors: Kim Young Dae , Song Dongbeom , Nam Hyo Suk , Lee Kijeong , Yoo Joonsang , Hong Geu-Ru , Lee Hye Sun , Nam Chung Mo , Heo Ji Hoe
Published: May 2015

Patent foramen ovale (PFO) is a potential cause of cryptogenic stroke, given the possibility of paradoxical embolism from venous to systemic circulation. D-dimer level is used to screen venous thrombosis. We investigated the risk of embolism and mortality according to the presence of PFO and D-dimer levels in cryptogenic stroke patients. A total of 570 first-ever cryptogenic stroke patients who underwent transesophageal echocardiography were included in this study. D-dimer was assessed using latex agglutination assay during admission. The association of long-term outcomes with the presence of PFO and D-dimer levels was investigated. PFO was detected in 241 patients (42.3 %). During a mean 34.0 ± 22.8 months of follow-up, all-cause death occurred in 58 (10.2 %) patients, ischaemic stroke in 33 (5.8 %), and pulmonary thromboembolism in 6 (1.1 %). Multivariate Cox regression analysis showed that a D-dimer level of > 1,000 ng/ml was an independent predictor for recurrent ischaemic stroke in patients with PFO (hazard ratio 5.341, 95 % confidence interval 1.648–17.309, p=0.005), but not in those without PFO. However, in patients without PFO, a D-dimer level of > 1,000 ng/ml was independently related with all-cause mortality. The risk of pulmonary thromboembolism tended to be high in patients with high D-dimer levels, regardless of PFO. Elevated D-dimer levels in cryptogenic stroke were predictive of the long-term outcome, which differed according to the presence of PFO. The coexistence of PFO and a high D-dimer level increased the risk of recurrent ischaemic stroke. The D-dimer test in cryptogenic stroke patients may be useful for predicting outcomes and deciding treatment strategy.
Anticoagulant therapy of cancer patients: Will patient selection increase overall survival?
Authors: Versteeg Henri , Borensztajn Keren , Spek C. Arnold
Published: May 2015

Already since the early 1800s, it has been recognised that malignancies may provoke thromboembolic complications, and indeed cancer patients are at increased risk of developing venous thrombosis. Interestingly, case control studies of deep-vein thrombosis suggested that low-molecular-weight heparin (LMWH) improved survival of cancer patients. This led to the hypothesis that cancer cells might ‘take advantage’ of a hypercoagulable state to more efficiently metastasise. Initial randomised placebo control trials showed that LMWH improve overall survival of cancer patients, especially in those patients with a relatively good prognosis. The failure of recent phase III trials, however, tempers enthusiasm for anticoagulant treatment in cancer patients despite an overwhelming body of literature showing beneficial effects of anticoagulants in preclinical models. Instead of discarding LMWH as potential (co)treatment modality in cancer patients, these disappointing recent trials should guide future preclinical research on anticoagulants in cancer biology. Most and for all, the underlying mechanisms by which coagulation drives tumour progression need to be elucidated. This could ultimately allow selection of cancer patients most likely to benefit from anticoagulant treatment and/or from targeted therapy downstream of coagulation factor signalling.
From ATP to PTP and Back
Authors: Bernardi Paolo , Di Lisa Fabio , Fogolari Federico , Lippe Giovanna
Published: May 2015

Mitochondria not only play a fundamental role in heart physiology but are also key effectors of dysfunction and death. This dual role assumes a new meaning after recent advances on the nature and regulation of the permeability transition pore, an inner membrane channel whose opening requires matrix Ca
2+
and is modulated by many effectors including reactive oxygen species, matrix cyclophilin D, Pi (inorganic phosphate), and matrix pH. The recent demonstration that the F-ATP synthase can reversibly undergo a Ca
2+
-dependent transition to form a channel that mediates the permeability transition opens new perspectives to the field. These findings demand a reassessment of the modifications of F-ATP synthase that take place in the heart under pathological conditions and of their potential role in determining the transition of F-ATP synthase from and energy-conserving into an energy-dissipating device.
Maintaining Ancient Organelles
Authors: Vega Rick B. , Horton Julie L. , Kelly Daniel P.
Published: May 2015

The ultrastructure of the cardiac myocyte is remarkable for the high density of mitochondria tightly packed between sarcomeres. This structural organization is designed to provide energy in the form of ATP to fuel normal pump function of the heart. A complex system comprised of regulatory factors and energy metabolic machinery, encoded by both mitochondrial and nuclear genomes, is required for the coordinate control of cardiac mitochondrial biogenesis, maturation, and high-capacity function. This process involves the action of a transcriptional regulatory network that builds and maintains the mitochondrial genome and drives the expression of the energy transduction machinery. This finely tuned system is responsive to developmental and physiological cues, as well as changes in fuel substrate availability. Deficiency of components critical for mitochondrial energy production frequently manifests as a cardiomyopathic phenotype, underscoring the requirement to maintain high respiration rates in the heart. Although a precise causative role is not clear, there is increasing evidence that perturbations in this regulatory system occur in the hypertrophied and failing heart. This review summarizes current knowledge and highlights recent advances in our understanding of the transcriptional regulatory factors and signaling networks that serve to regulate mitochondrial biogenesis and function in the mammalian heart.
Regulated Necrotic Cell Death
Authors: Karch Jason , Molkentin Jeffery D.
Published: May 2015

Although the molecular effectors of apoptotic cell death have been largely annotated over the past 30 years, leading to a strong biological understanding of this process and its importance in cell biology, cell death through necrosis has only recently been accepted as a similarly regulated process with definable molecular effectors. The mitochondria are important and central mediators of both apoptosis and regulated necrosis. In apoptosis, the B-cell leukemia/lymphoma 2 (Bcl-2) family members Bcl-2–associated protein x (Bax) and Bcl-2 homologues antagonist/killer (Bak) undergo oligomerization in the outer mitochondrial membrane resulting in the release of apoptosis inducing substrates and the activation of caspases and nucleases. In contrast, during necrosis the mitochondria become dysfunctional and maladaptive in conjunction with reactive oxygen species production and the loss of ATP production, in part through opening of the mitochondrial permeability transition pore. Although regulated necrosis is caspase-independent, recent evidence has shown that it still requires the apoptotic regulators Bax/Bak, which can regulate the permeability characteristics of the outer mitochondrial membrane in their nonoligomerized state. Here, we review the nonapoptotic side of Bcl-2 family, specifically the role of Bax/Bak in regulated necrotic cell death. We will also discuss how these Bcl-2 family member effectors could be part of a larger integrated network that ultimately decides the fate of a given cell somewhere within a molecular continuum between apoptosis and regulated necrosis.
Mitochondrial Reactive Oxygen Species at the Heart of the Matter
Authors: Kornfeld Opher S. , Hwang Sunhee , Disatnik Marie-Hélène , Chen Che-Hong , Qvit Nir , Mochly-Rosen Daria
Published: May 2015

Reactive oxygen species (ROS) have been implicated in a variety of age-related diseases, including multiple cardiovascular disorders. However, translation of ROS scavengers (antioxidants) into the clinic has not been successful. These antioxidants grossly reduce total levels of cellular ROS including ROS that participate in physiological signaling. In this review, we challenge the traditional antioxidant therapeutic approach that targets ROS directly with novel approaches that improve mitochondrial functions to more effectively treat cardiovascular diseases.
The Ins and Outs of Mitochondrial Calcium
Authors: Finkel Toren , Menazza Sara , Holmström Kira M. , Parks Randi J. , Liu Julia , Sun Junhui , Liu Jie , Pan Xin , Murphy Elizabeth
Published: May 2015

Calcium is thought to play an important role in regulating mitochondrial function. Evidence suggests that an increase in mitochondrial calcium can augment ATP production by altering the activity of calcium-sensitive mitochondrial matrix enzymes. In contrast, the entry of large amounts of mitochondrial calcium in the setting of ischemia-reperfusion injury is thought to be a critical event in triggering cellular necrosis. For many decades, the details of how calcium entered the mitochondria remained a biological mystery. In the past few years, significant progress has been made in identifying the molecular components of the mitochondrial calcium uniporter complex. Here, we review how calcium enters and leaves the mitochondria, the growing insight into the topology, stoichiometry and function of the uniporter complex, and the early lessons learned from some initial mouse models that genetically perturb mitochondrial calcium homeostasis.
Fetal Mammalian Heart Generates a Robust Compensatory Response to Cell Loss
Authors: Sturzu Anthony C. , Rajarajan Kuppusamy , Passer Derek , Plonowska Karolina , Riley Alyssa , Tan Timothy C. , Sharma Arun , Xu Adele F. , Engels Marc C. , Feistritzer Rebecca , Li Guang , Selig Martin K. , Geissler Richard , Robertson Keston D. , Scherrer-Crosbie Marielle , Domian Ibrahim J. , Wu Sean M.
Published: May 2015

Background—

Heart development is tightly regulated by signaling events acting on a defined number of progenitor and differentiated cardiac cells. Although loss of function of these signaling pathways leads to congenital malformation, the consequences of cardiac progenitor cell or embryonic cardiomyocyte loss are less clear. In this study, we tested the hypothesis that embryonic mouse hearts exhibit a robust mechanism for regeneration after extensive cell loss.

Methods and Results—

By combining a conditional cell ablation approach with a novel blastocyst complementation strategy, we generated murine embryos that exhibit a full spectrum of cardiac progenitor cell or cardiomyocyte ablation. Remarkably, ablation of up to 60% of cardiac progenitor cells at embryonic day 7.5 was well tolerated and permitted embryo survival. Ablation of embryonic cardiomyocytes to a similar degree (50% to 60%) at embryonic day 9.0 could be fully rescued by residual myocytes with no obvious adult cardiac functional deficit. In both ablation models, an increase in cardiomyocyte proliferation rate was detected and accounted for at least some of the rapid recovery of myocardial cellularity and heart size.

Conclusion—

Our study defines the threshold for cell loss in the embryonic mammalian heart and reveals a robust cardiomyocyte compensatory response that sustains normal fetal development.