bluuebunny/crossref_metadata_2025 huggingface dataset:
SERCA2 activity is involved in the CNP‐mediated functional responses in failing rat myocardium
Authors: Moltzau L R , Aronsen J M , Meier S , Nguyen C H T , Hougen K , Ørstavik Ø , Sjaastad I , Christensen G , Skomedal T , Osnes J‐B , Levy F O , Qvigstad E
Published: August 2013

Background and Purposes

Myocardial C‐type natriuretic peptide (CNP) levels are increased in heart failure. CNP can induce negative inotropic (NIR) and positive lusitropic responses (LR) in normal hearts, but its effects in failing hearts are not known. We studied the mechanism of CNP‐induced NIR and LR in failing hearts and determined whether sarcoplasmatic reticulum Ca2+ ATPase2 (SERCA2) activity is essential for these responses.

Experimental Approach

Contractility, cGMP levels, Ca2+ transient amplitudes and protein phosphorylation were measured in left ventricular muscle strips or ventricular cardiomyocytes from failing hearts of Wistar rats 6 weeks after myocardial infarction.

Key Results

CNP increased cGMP levels, evoked a NIR and LR in muscle strips, and caused phospholamban (PLB) Ser16 and troponin I (TnI) Ser23/24 phosphorylation in cardiomyocytes. Both the NIR and LR induced by CNP were reduced in the presence of a PKG blocker/cGMP analogue (Rp‐8‐Br‐Pet‐cGMPS) and the SERCA inhibitor thapsigargin. CNP increased the amplitude of the Ca2+ transient and increased SERCA2 activity in cardiomyocytes. The CNP‐elicited NIR and LR were not affected by the L‐type Ca2+ channel activator BAY‐K8644, but were abolished in the presence of isoprenaline (induces maximal activation of cAMP pathway). This suggests that phosphorylation of PLB and TnI by CNP causes both a NIR and LR. The NIR to CNP in mouse heart was abolished 8 weeks after cardiomyocyte‐specific inactivation of the SERCA2 gene.

Conclusions and Implications

We conclude that CNP‐induced PLB and TnI phosphorylation by PKG in concert mediate both a predictable LR as well as the less expected NIR in failing hearts.
Systemic and cerebral exposure to and pharmacokinetics of flavonols and terpene lactones after dosing standardized Ginkgo biloba leaf extracts to rats via different routes of administration
Authors: Chen Feng , Li Li , Xu Fang , Sun Yan , Du Feifei , Ma Xutao , Zhong Chenchun , Li Xiuxue , Wang Fengqing , Zhang Nating , Li Chuan
Published: August 2013

Background and Purpose

Flavonols and terpene lactones are putatively responsible for the properties of Ginkgo biloba leaf extracts that relate to prevention and treatment of cardiovascular disease and cerebral insufficiency. Here, we characterized rat systemic and cerebral exposure to these ginkgo compounds after dosing, as well as the compounds’ pharmacokinetics.

Experimental Approach

Rats received single or multiple doses of ShuXueNing injection (prepared from GBE50 for intravenous administration) or GBE50 (a standardized extract of G. biloba leaves for oral administration). Brain delivery of the ginkgo compounds was assessed with microdialysis. Various rat samples were analysed using liquid chromatography/mass spectrometry.

Key Results

Slow terminal elimination features of the flavonols counterbalanced the influence of poor oral bioavailability on their systemic exposure levels, which also resulted in significant accumulation of the compounds in plasma during the subchronic treatment with ShuXueNing injection and GBE50. Unlike the flavonols, the terpene lactones had poor enterohepatic circulation due to their rapid renal excretion and unknown metabolism. The flavonol glycosides occurred as major forms in plasma after dosing with ShuXueNing injection, while the flavonol aglycone conjugates were predominant in plasma after dosing with GBE50. Cerebral exposure was negligible for the flavonols and low for the terpene lactones.

Conclusion and Implications

Unlike the significant systemic exposure levels, the levels of cerebral exposure to the flavonols and terpene lactones are low. The elimination kinetic differences between the two classes of ginkgo compounds influence their relative systemic exposure levels. The information gained is relevant to linking ginkgo administration to the medicinal effects.
NFAT2 inhibitor ameliorates diabetic nephropathy and podocyte injury in db/db mice
Authors: Zhang Li , Li Ruizhao , Shi Wei , Liang Xinling , Liu Shuangxin , Ye Zhiming , Yu Chunping , Chen Yuanhan , Zhang Bin , Wang Wenjian , Lai Yuxiong , Ma Jianchao , Li Zhuo , Tan Xiaofan
Published: August 2013

Background and Purpose

Podocyte injury plays a key role in the development of diabetic nephropathy (DN). We have recently shown that 11R‐VIVIT, an inhibitor of cell‐permeable nuclear factor of activated T‐cells (NFAT), attenuates podocyte apoptosis induced by high glucose in vitro. However, it is not known whether 11R‐VIVIT has a protective effect on DN, especially podocyte injury, under in vivo diabetic conditions. Hence, we examined the renoprotective effects of 11R‐VIVIT in diabetic db/db mice and the possible mechanisms underlying its protective effects on podocyte injury in vivo and in vitro.

Experimental Approach

Type 2 diabetic db/db mice received i.p. injections of 11R‐VIVIT (1 mg·kg−1) three times a week and were killed after 8 weeks. Immortalized mouse podocytes were cultured under different experimental conditions.

Key Results

11R‐VIVIT treatment markedly attenuated the albuminuria in diabetic db/db mice and also alleviated mesangial matrix expansion and podocyte injury. However, body weight, food and water intake, and glucose levels were unaffected. It also attenuated the increased NFAT2 activation and enhanced urokinase‐type plasminogen activator receptor (uPA receptor) expression in glomerulor podocytes. In cultured podocytes, the increased nuclear accumulation of NFAT2 and uPA receptor expression induced by high glucose treatment was prevented by 11R‐VIVIT or NFAT2‐knockdown; this was accompanied by improvements in the filtration barrier function of the podocyte monolayer.

Conclusions and Implications

The NFAT inhibitor 11R‐VIVIT might be a useful therapeutic strategy for protecting podocytes and treating DN. The calcinerin/NFAT2/uPA receptor signalling pathway should be exploited as a therapeutic target for protecting podocytes from injury in DN.
Structural and functional insights into the juxtamembranous amino‐terminal tail and extracellular loop regions of class B GPCRs
Authors: Dong M , Koole C , Wootten D , Sexton P M , Miller L J
Published: August 2013

Class B guanine nucleotide‐binding protein GPCRs share heptahelical topology and signalling via coupling with heterotrimeric G proteins typical of the entire superfamily of GPCRs. However, they also exhibit substantial structural differences from the more extensively studied class A GPCRs. Even their helical bundle region, most conserved across the superfamily, is predicted to differ from that of class A GPCRs. Much is now known about the conserved structure of the amino‐terminal domain of class B GPCRs, coming from isolated NMR and crystal structures, but the orientation of that domain relative to the helical bundle is unknown, and even less is understood about the conformations of the juxtamembranous amino‐terminal tail or of the extracellular loops linking the transmembrane segments. We now review what is known about the structure and function of these regions of class B GPCRs. This comes from indirect analysis of structure–function relationships elucidated by mutagenesis and/or ligand modification and from the more direct analysis of spatial approximation coming from photoaffinity labelling and cysteine trapping studies. Also reviewed are the limited studies of structure of some of these regions. No dominant theme was recognized for the structures or functional roles of distinct regions of these juxtamembranous portions of the class B GPCRs. Therefore, it is likely that a variety of molecular strategies can be engaged for docking of agonist ligands and for initiation of conformational changes in these receptors that would be expected to converge to a common molecular mechanism for activation of intracellular signalling cascades.

Linked Articles

This article is part of a themed section on Molecular Pharmacology of GPCRs. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue‐5
Comparison of ultra‐fast 2D and 3D ligand and target descriptors for side effect prediction and network analysis in polypharmacology
Authors: Cortés‐Cabrera Alvaro , Morris Garrett M , Finn Paul W , Morreale Antonio , Gago Federico
Published: August 2013

Background and Purpose

Some existing computational methods are used to infer protein targets of small molecules and can therefore be used to find new targets for existing drugs, with the goals of re‐directing the molecule towards a different therapeutic purpose or explaining off‐target effects due to multiple targeting. Inherent limitations, however, arise from the fact that chemical analogy is calculated on the basis of common frameworks or scaffolds and also because target information is neglected. The method we present addresses these issues by taking into account 3D information from both the ligand and the target.

Experimental Approach

ElectroShape is an established method for ultra‐fast comparison of the shapes and charge distributions of ligands that is validated here for prediction of on‐target activities, off‐target profiles and adverse effects of drugs and drug‐like molecules taken from the DrugBank database.

Key Results

The method is shown to predict polypharmacology profiles and relate targets from two complementary viewpoints (ligand‐ and target‐based networks).

Conclusions and Implications

The open‐access web tool presented here (http://ub.cbm.uam.es/chemogenomics/) allows interactive navigation in a unified ‘pharmacological space’ from the viewpoints of both ligands and targets. It also enables prediction of pharmacological profiles, including likely side effects, for new compounds. We hope this web interface will help many pharmacologists to become aware of this new paradigm (up to now mostly used in the realm of the so‐called ‘chemical biology’) and encourage its use with a view to revealing ‘hidden’ relationships between new and existing compounds and pharmacologically relevant targets.
Signalling profile differences: paliperidone versus risperidone
Authors: Clarke W P , Chavera T A , Silva M , Sullivan L C , Berg K A
Published: August 2013

Background and Purpose

Paliperidone is an active metabolite of the second‐generation atypical antipsychotic, risperidone recently approved for the treatment of schizophrenia and schizoaffective disorder. Because paliperidone differs from risperidone by only a single hydroxyl group, questions have been raised as to whether there are significant differences in the effects elicited between these two drugs.

Experimental Approach

We compared the relative efficacies of paliperidone versus risperidone to regulate several cellular signalling pathways coupled to four selected GPCR targets that are important for either therapeutic or adverse effects: human dopamine D2, human serotonin 2A receptor subtype (5‐HT2A), human serotonin 2C receptor subtype and human histamine H1 receptors.

Key Results

Whereas the relative efficacies of paliperidone and risperidone were the same for some responses, significant differences were found for several receptor‐signalling systems, with paliperidone having greater or less relative efficacy than risperidone depending upon the receptor–response pair. Interestingly, for 5‐HT2A‐mediated recruitment of β‐arrestin, 5‐HT2A‐mediated sensitization of ERK, and dopamine D2‐mediated sensitization of adenylyl cyclase signalling, both paliperidone and risperidone behaved as agonists.

Conclusions and Implications

These results suggest that the single hydroxyl group of paliperidone promotes receptor conformations that can differ from those of risperidone leading to differences in the spectrum of regulation of cellular signal transduction cascades. Such differences in signalling at the cellular level could lead to differences between paliperidone and risperidone in therapeutic efficacy or in the generation of adverse effects.
Orexin/hypocretin receptor signalling: a functional perspective
Authors: Leonard C S , Kukkonen J P
Published: August 2013

Multiple homeostatic systems are regulated by orexin (hypocretin) peptides and their two known GPCRs. Activation of orexin receptors promotes waking and is essential for expression of normal sleep and waking behaviour, with the sleep disorder narcolepsy resulting from the absence of orexin signalling. Orexin receptors also influence systems regulating appetite/metabolism, stress and reward, and are found in several peripheral tissues. Nevertheless, much remains unknown about the signalling pathways and targets engaged by native receptors. In this review, we integrate knowledge about the orexin receptor signalling capabilities obtained from studies in expression systems and various native cell types (as presented in Kukkonen and Leonard, this issue of British Journal of Pharmacology) with knowledge of orexin signalling in different tissues. The tissues reviewed include the CNS, the gastrointestinal tract, the pituitary gland, pancreas, adrenal gland, adipose tissue and the male reproductive system. We also summarize the findings in different native and recombinant cell lines, especially focusing on the different cascades in CHO cells, which is the most investigated cell line. This reveals that while a substantial gap exists between what is known about orexin receptor signalling and effectors in recombinant systems and native systems, mounting evidence suggests that orexin receptor signalling is more diverse than originally thought. Moreover, rather than being restricted to orexin receptor ‘overexpressing’ cells, this signalling diversity may be utilized by native receptors in a site‐specific manner.

Linked Articles

This article is part of a themed section on Orexin Receptors. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue‐2
Pharmacological profiling of the TRPV3 channel in recombinant and native assays
Authors: Grubisha Olivera , Mogg Adrian J , Sorge Jessica L , Ball Laura‐Jayne , Sanger Helen , Ruble Cara L A , Folly Elizabeth A , Ursu Daniel , Broad Lisa M
Published: August 2013

Background and Purpose

Transient receptor potential vanilloid subtype 3 (TRPV3) is implicated in nociception and certain skin conditions. As such, it is an attractive target for pharmaceutical research. Understanding of endogenous TRPV3 function and pharmacology remains elusive as selective compounds and native preparations utilizing higher throughput methodologies are lacking. In this study, we developed medium‐throughput recombinant and native cellular assays to assess the detailed pharmacological profile of human, rat and mouse TRPV3 channels.

Experimental Approach

Medium‐throughput cellular assays were developed using a Ca2+‐sensitive dye and a fluorescent imaging plate reader. Human and rat TRPV3 pharmacology was examined in recombinant cell lines, while the mouse 308 keratinocyte cell line was used to assess endogenous TRPV3 activity.

Key Results

A recombinant rat TRPV3 cellular assay was successfully developed after solving a discrepancy in the published rat TRPV3 protein sequence. A medium‐throughput, native, mouse TRPV3 keratinocyte assay was also developed and confirmed using genetic approaches. Whereas the recombinant human and rat TRPV3 assays exhibited similar agonist and antagonist profiles, the native mouse assay showed important differences, namely, TRPV3 activity was detected only in the presence of potentiator or during agonist synergy. Furthermore, the native assay was more sensitive to block by some antagonists.

Conclusions and Implications

Our findings demonstrate similarities but also notable differences in TRPV3 pharmacology between recombinant and native systems. These findings offer insights into TRPV3 function and these assays should aid further research towards developing TRPV3 therapies.

Linked Articles

This article is part of a themed section on the pharmacology of TRP channels. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue‐10
Selective, potent blockade of the IRE1 and ATF6 pathways by 4‐phenylbutyric acid analogues
Authors: Zhang Hui , Nakajima Shotaro , Kato Hironori , Gu Liubao , Yoshitomi Tatsuya , Nagai Kaoru , Shinmori Hideyuki , Kokubo Susumu , Kitamura Masanori
Published: August 2013

Background and Purpose

4‐Phenylbutyric acid (4‐PBA) is a chemical chaperone that eliminates the accumulation of unfolded proteins in the endoplasmic reticulum (ER). However, its chaperoning ability is often weak and unable to attenuate the unfolded protein response (UPR) in vitro or in vivo. To develop more potent chemical chaperones, we synthesized six analogues of 4‐PBA and evaluated their pharmacological actions on the UPR.

Experimental Approach

NRK‐52E cells were treated with ER stress inducers (tunicamycin or thapsigargin) in the presence of each of the 4‐PBA analogues; the suppressive effects of these analogues on the UPR were assessed using selective indicators for individual UPR pathways.

Key Results

2‐POAA‐OMe, 2‐POAA‐NO2 and 2‐NOAA, but not others, suppressed the induction of ER stress markers GRP78 and CHOP. This suppressive effect was more potent than that of 4‐PBA. Of the three major UPR branches, the IRE1 and ATF6 pathways were markedly blocked by these compounds, as indicated by suppression of XBP1 splicing, inhibition of UPRE and ERSE activation, and inhibition of JNK phosphorylation. Unexpectedly, however, these agents did not inhibit phosphorylation of PERK and eIF2α triggered by ER stress. These compounds dose‐dependently inhibited the early activation of NF‐κB in ER stress‐exposed cells. 2‐POAA‐OMe and 2‐POAA‐NO2 also inhibited ER stress‐induced phosphorylation of Akt.

Conclusion and Implications

The 4‐PBA analogues 2‐POAA‐OMe, 2‐POAA‐NO2 and 2‐NOAA strongly inhibited activation of the IRE1 and ATF6 pathways and downstream pathogenic targets, including NF‐κB and Akt, in ER stress‐exposed cells. These compounds may be useful for therapeutic intervention in ER stress‐related pathological conditions.
Pharmacological characterization of a novel centrally permeable P2X7 receptor antagonist: JNJ‐47965567
Authors: Bhattacharya Anindya , Wang Qi , Ao Hong , Shoblock James R , Lord Brian , Aluisio Leah , Fraser Ian , Nepomuceno Diane , Neff Robert A , Welty Natalie , Lovenberg Timothy W , Bonaventure Pascal , Wickenden Alan D , Letavic Michael A
Published: August 2013

Background and Purpose

An increasing body of evidence suggests that the purinergic receptor P2X, ligand‐gated ion channel, 7 (P2X7) in the CNS may play a key role in neuropsychiatry, neurodegeneration and chronic pain. In this study, we characterized JNJ‐47965567, a centrally permeable, high‐affinity, selective P2X7 antagonist.

Experimental Approach

We have used a combination of in vitro assays (calcium flux, radioligand binding, electrophysiology, IL‐1β release) in both recombinant and native systems. Target engagement of JNJ‐47965567 was demonstrated by ex vivo receptor binding autoradiography and in vivo blockade of Bz‐ATP induced IL‐1β release in the rat brain. Finally, the efficacy of JNJ‐47965567 was tested in standard models of depression, mania and neuropathic pain.

Key Results

JNJ‐47965567 is potent high affinity (pKi 7.9 ± 0.07), selective human P2X7 antagonist, with no significant observed speciation. In native systems, the potency of the compound to attenuate IL‐1β release was 6.7 ± 0.07 (human blood), 7.5 ± 0.07 (human monocytes) and 7.1 ± 0.1 (rat microglia). JNJ‐47965567 exhibited target engagement in rat brain, with a brain EC50 of 78 ± 19 ng·mL−1 (P2X7 receptor autoradiography) and functional block of Bz‐ATP induced IL‐1β release. JNJ‐47965567 (30 mg·kg−1) attenuated amphetamine‐induced hyperactivity and exhibited modest, yet significant efficacy in the rat model of neuropathic pain. No efficacy was observed in forced swim test.

Conclusion and Implications

JNJ‐47965567 is centrally permeable, high affinity P2X7 antagonist that can be used to probe the role of central P2X7 in rodent models of CNS pathophysiology.
Effect of chirality and lipophilicity in the functional activity of evodiamine and its analogues at TRPV1 channels
Authors: De Petrocellis Luciano , Schiano Moriello Aniello , Fontana Gabriele , Sacchetti Alessandro , Passarella Daniele , Appendino Giovanni , Di Marzo Vincenzo
Published: August 2013

Background and Purpose

Evodiamine, a racemic quinazolinocarboline alkaloid isolated from the traditional Chinese medicine Evodiae fructus, has been reported to act as an agonist of the transient receptor potential vanilloid type‐1 (TRPV1) cation channel both in vitro and in vivo. Evodiamine is structurally different from all known TRPV1 activators, and has significant clinical potential as a thermogenic agent. Nevertheless, the molecular bases for its actions are still poorly understood.

Experimental Approach

To investigate the structure‐activity relationships of evodiamine, the natural racemate was resolved, and a series of 23 synthetic analogues was prepared, using as the end point the intracellular Ca2+ elevation in HEK‐293 cells stably overexpressing either the human or the rat recombinant TRPV1.

Key Results

S‐(+) evodiamine was more efficacious and potent than R‐(−) evodiamine, and a new potent lead (Evo30) was identified, more potent than the reference TRPV1 agonist, capsaicin. In general, potency and efficacy correlated with the lipophilicity of the analogues. Like other TRPV1 agonists, several synthetic analogues could efficiently desensitize TRPV1 to activation by capsaicin.

Conclusions and Implications

Evodiamine qualifies as structurally unique lead structure to develop new potent TRPV1 agonists/desensitizers.

Linked Articles

This article is part of a themed section on the pharmacology of TRP channels. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue‐10
3,3′‐Diindolylmethane ameliorates experimental hepatic fibrosis via inhibiting miR‐21 expression
Authors: Zhang Zhengping , Gao Zhongfei , Hu Wei , Yin Shan , Wang Chunming , Zang Yuhui , Chen Jiangning , Zhang Junfeng , Dong Lei
Published: August 2013

Background and Purpose

Hepatic fibrosis is a type of liver disease characterized by excessive collagen deposition produced by activated hepatic stellate cells (HSCs), and no appropriate drug treatment is available clinically. The microRNA, miR‐21 exhibits an important role in the pathogenesis and progression of hepatic fibrosis. 3,3′‐Diindolylmethane (DIM) is a natural autolytic product in plants and can down‐regulate miR‐21 expression. Here we have assessed the therapeutic effects of DIM against hepatic fibrosis and investigated the underlying mechanisms.

Experimental Approach

The effects of DIM on HSC activation were measured by analysing the expression of α‐smooth muscle actin and collagen I in both HSC‐T6 cell line and primary HSCs. Expression of miR‐21 was also measured after DIM treatment and the therapeutic effect of DIM was further studied in vivo, using the model of hepatic fibrosis induced by thioacetamide in mice. The antagonist oligonucleotide, antagomir‐21, was also used to suppress the effects of miR‐21.

Key Results

DIM suppressed the central TGF‐β signalling pathway underlying HSC activation by down‐regulating the expression of miR‐21. The decreased miR‐21 expression was achieved by inhibiting the activity of the transcription factor, AP‐1. Moreover, DIM blunted the activation phenotype of primary HSCs. Administration of DIM in vivo attenuated liver fibrosis induced by thioacetamide, as assessed by collagen deposition and profiles of profibrogenic markers.

Conclusions and Implications

DIM shows potential as a therapeutic agent for the treatment of hepatic fibrosis.
Orexin/hypocretin receptor signalling cascades
Authors: Kukkonen J P , Leonard C S
Published: August 2013

Orexin (hypocretin) peptides and their two known G‐protein‐coupled receptors play essential roles in sleep–wake control and powerfully influence other systems regulating appetite/metabolism, stress and reward. Consequently, drugs that influence signalling by these receptors may provide novel therapeutic opportunities for treating sleep disorders, obesity and addiction. It is therefore critical to understand how these receptors operate, the nature of the signalling cascades they engage and their physiological targets. In this review, we evaluate what is currently known about orexin receptor signalling cascades, while a sister review (Leonard & Kukkonen, this issue) focuses on tissue‐specific responses. The evidence suggests that orexin receptor signalling is multifaceted and is substantially more diverse than originally thought. Indeed, orexin receptors are able to couple to members of at least three G‐protein families and possibly other proteins, through which they regulate non‐selective cation channels, phospholipases, adenylyl cyclase, and protein and lipid kinases. In the central nervous system, orexin receptors produce neuroexcitation by postsynaptic depolarization via activation of non‐selective cation channels, inhibition of K+ channels and activation of Na+/Ca2+ exchange, but they also can stimulate the release of neurotransmitters by presynaptic actions and modulate synaptic plasticity. Ca2+ signalling is also prominently influenced by these receptors, both via the classical phospholipase C−Ca2+ release pathway and via Ca2+ influx, mediated by several pathways. Upon longer‐lasting stimulation, plastic effects are observed in some cell types, while others, especially cancer cells, are stimulated to die. Thus, orexin receptor signals appear highly tunable, depending on the milieu in which they are operating.

Linked Articles

This article is part of a themed section on Orexin Receptors. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue‐2
Central 5‐HT1A receptor‐mediated modulation of heart rate dynamics and its adjustment by conditioned and unconditioned fear in mice
Authors: Youn Jiun , Hager Torben , Misane Ilga , Pieneman Anton W , Jansen René F , Ögren Sven Ove , Meyer Michael , Stiedl Oliver
Published: August 2013

Background and Purpose

The beat‐by‐beat fluctuation (dynamics) of heart rate (HR) depends on centrally mediated control of the autonomic nervous system (ANS) reflecting the physiological state of an organism. 5‐HT1A receptors are implicated in affective disorders,associated with ANS dysregulation which increases cardiac risk but their role in autonomic HR regulation under physiological conditions is insufficiently characterized.

Experimental Approach

The effects of subcutaneously administered 5‐HT1A receptor ligands on HR dynamics were investigated in C57BL/6 mice during stress‐free conditions and emotional challenge (recall of fear conditioned to an auditory stimulus and novelty exposure) using time domain and non‐linear HR analyses.

Key Results

Pre‐training treatment with of 8‐OH‐DPAT (0.5 mg·kg−1, s.c.) prevented conditioned tachycardia in the retention test indicating impaired fear memory. Pretest 5‐HT1A receptor activation by 8‐OH‐DPAT (0.5 but not 0.1 and 0.02 mg·kg−1) caused bradycardia and increased HR variability. 8‐OH‐DPAT (0.5 mg·kg−1) lowered the unconditioned and conditioned tachycardia from ∼750 to ∼550 bpm, without changing the conditioned HR response to the sound. 8‐OH‐DPAT induced profound QT prolongation and bradyarrhythmic episodes. Non‐linear analysis indicated a pathological state of HR dynamics after 8‐OH‐DPAT (0.5 mg·kg−1) with ANS hyperactivation impairing HR adaptability. The 5‐HT1A receptor antagonist WAY‐100635 (0.03 mg·kg−1) blocked these effects of 8‐OH‐DPAT.

Conclusions and Implications

Pre‐training 5‐HT1A receptor activation by 8‐OH‐DPAT (0.5 mg·kg−1) impaired memory of conditioned auditory fear based on an attenuated HR increase, whereas pretest administration did not prevent the fear‐conditioned HR increase but induced pathological HR dynamics through central ANS dysregulation with cardiac effects similar to acute SSRI overdose.
Small‐interfering RNAs (siRNAs) as a promising tool for ocular therapy
Authors: Guzman‐Aranguez A , Loma P , Pintor J
Published: August 2013

RNA interference (RNAi) can be used to inhibit the expression of specific genes in vitro and in vivo, thereby providing an extremely useful tool for investigating gene function. Progress in the understanding of RNAi‐based mechanisms has opened up new perspectives in therapeutics for the treatment of several diseases including ocular disorders. The eye is currently considered a good target for RNAi therapy mainly because it is a confined compartment and, therefore, enables local delivery of small‐interfering RNAs (siRNAs) by topical instillation or direct injection. However, delivery strategies that protect the siRNAs from degradation and are suitable for long‐term treatment would be help to improve the efficacy of RNAi‐based therapies for ocular pathologies. siRNAs targeting critical molecules involved in the pathogenesis of glaucoma, retinitis pigmentosa and neovascular eye diseases (age‐related macular degeneration, diabetic retinopathy and corneal neovascularization) have been tested in experimental animal models, and clinical trials have been conducted with some of them. This review provides an update on the progress of RNAi in ocular therapeutics, discussing the advantages and drawbacks of RNAi‐based therapeutics compared to previous treatments.
UDP induces intestinal epithelial migration via the P2Y6 receptor
Authors: Nakamura Tatsuro , Murata Takahisa , Hori Masatoshi , Ozaki Hiroshi
Published: August 2013

Background and Purpose

Extracellular nucleotides are released at high concentrations from damaged cells and function through P2 receptor activation. Intestinal epithelial restitution, which is defined as cell migration independent of cell proliferation, is an important initial step in the process of wound healing. In this study, we investigated the role of extracellular nucleotides in intestinal epithelial migratory responses.

Experimental Approach

Wound‐healing and trans‐well migration assays were performed with a rat intestinal epithelial cell line (IEC‐6). The concentrations of extracellular nucleotides released from injured IEC‐6 cells were measured by HPLC. TGF‐β expression was assessed by RT‐PCR and elisa.

Key Results

Scratching the monolayer of IEC‐6 cells induced cell migration. Pretreatment with apyrase or MRS2578, a selective P2Y6 antagonist, inhibited the wound‐induced cell migration. Among the cellular nucleotides, only ATP and uridine 5'‐diphosphate (UDP) were detected in the culture medium after cell wounding. Exogenously applied UDP dose‐dependently enhanced the migration more effectively than ATP but did not induce proliferation. In addition, cell wounding and UDP increased the expression of TGF‐β, and both the wound‐induced and UDP‐enhanced migration were inhibited by MRS2578 or ALK5Inhibitor (ALK5i), a TGF‐β receptor blocker. Furthermore, cell wounding and UDP stimulation up‐regulated the expression of P2Y6 receptor mRNA, and this effect was suppressed by MRS2578 or ALK5i.

Conclusion and Implications

Wound‐induced UDP evokes intestinal epithelial restitution by activation of P2Y6 receptors, which mediates de novo synthesis of TGF‐β. In addition, the expression of P2Y6 receptors is increased by cell wounding and UDP, which constitutes a positive‐feedback loop for mucosal repair.
Glycine receptor mouse mutants: model systems for human hyperekplexia
Authors: Schaefer Natascha , Langlhofer Georg , Kluck Christoph J , Villmann Carmen
Published: August 2013

Human hyperekplexia is a neuromotor disorder caused by disturbances in inhibitory glycine‐mediated neurotransmission. Mutations in genes encoding for glycine receptor subunits or associated proteins, such as GLRA1, GLRB, GPHN and ARHGEF9, have been detected in patients suffering from hyperekplexia. Classical symptoms are exaggerated startle attacks upon unexpected acoustic or tactile stimuli, massive tremor, loss of postural control during startle and apnoea. Usually patients are treated with clonazepam, this helps to dampen the severe symptoms most probably by up‐regulating GABAergic responses. However, the mechanism is not completely understood. Similar neuromotor phenotypes have been observed in mouse models that carry glycine receptor mutations. These mouse models serve as excellent tools for analysing the underlying pathomechanisms. Yet, studies in mutant mice looking for postsynaptic compensation of glycinergic dysfunction via an up‐regulation in GABAA receptor numbers have failed, as expression levels were similar to those in wild‐type mice. However, presynaptic adaptation mechanisms with an unusual switch from mixed GABA/glycinergic to GABAergic presynaptic terminals have been observed. Whether this presynaptic adaptation explains the improvement in symptoms or other compensation mechanisms exist is still under investigation. With the help of spontaneous glycine receptor mouse mutants, knock‐in and knock‐out studies, it is possible to associate behavioural changes with pharmacological differences in glycinergic inhibition. This review focuses on the structural and functional characteristics of the various mouse models used to elucidate the underlying signal transduction pathways and adaptation processes and describes a novel route that uses gene‐therapeutic modulation of mutated receptors to overcome loss of function mutations.
Labour Migration and Social Networks Participation in Southern Mozambique
Authors: Gallego Juan M. , Mendola Mariapia
Published: August 2013

This paper investigates how social networks in poor developing settings are affected by migration. Using a unique household survey from southern Mozambique, we test the role of labour mobility in shaping participation in groups and interhousehold cooperation by migrant‐sending households in village economies at origin. We find that migration cum remittances boosts household engagement in community‐based social networks. Our findings are robust to alternative definitions of social interaction and to endogeneity concerns, suggesting that stable migration ties and higher income stability through remittances may decrease participation constraints and increase household commitment in cooperative arrangements in migrant‐sending communities.
Myotonic dystrophy is not only a disease affecting the muscles, it is also a CNS disorder
Authors: Meola G.
Published: August 2013

Click here to view the accompanying paper in this issue.
Interictal interleukin‐17A levels are elevated and correlate with seizure severity of epilepsy patients
Authors: Mao Ling‐Yan , Ding Jing , Peng Wei‐Feng , Ma Yu , Zhang Yu‐Hao , Fan Wei , Wang Xin
Published: August 2013

Interleukin 17A (IL‐17A) is implicated in the pathogenesis of several neuroimmunologic diseases. We aimed to evaluate the relationship between IL‐17A and seizure severity in patients with epilepsy. Seventy patients with probable symptomatic epilepsy and 68 healthy controls were included. Interictal serum IL‐17A and related cytokine (IL‐23, IL‐6, IL‐1β, interferon gamma (IFN‐γ), and IL‐10) levels were measured. The relationship between seizure severity and cytokine concentrations was assessed by Spearman correlation and multivariate linear regression test. IL‐17A levels in the cerebrospinal fluid (CSF) were tested in 30 additional patients with epilepsy, either in the postictal or interictal period and 15 patients with idiopathic inflammatory demyelinating diseases (IIDDs). Interictal serum IL‐17A levels were significantly elevated in patients with epilepsy compared to controls. IL‐6, IFN‐γ, and IL‐1β levels were also markedly elevated. Spearman correlation analysis revealed positive correlation between IL‐17A, IL‐6 levels and Veterans Administration Seizures Frequency and Severity Rating Scale score(VA score); IFN‐γ, IL‐10 levels, and National Hospital Seizure Severity Scale (NHS3) score. In addition, IL‐17A levels correlated significantly with seizure frequency. Multivariate linear regression test showed that only IL‐17A levels were independently positively correlated with VA scores (B = 0.288, p = 0.027). Postictal IL‐17A levels in the CSF were significantly elevated compared to interictal patients and patients with IIDDs. Our results suggest that interictal IL‐17A levels correlated highly with seizure severity.
Source localization of rhythmic ictal EEG activity: A study of diagnostic accuracy following STARD criteria
Authors: Beniczky Sándor , Lantz Göran , Rosenzweig Ivana , Åkeson Per , Pedersen Birthe , Pinborg Lars H. , Ziebell Morten , Jespersen Bo , Fuglsang‐Frederiksen Anders
Published: August 2013

Purpose

Although precise identification of the seizure‐onset zone is an essential element of presurgical evaluation, source localization of ictal electroencephalography (EEG) signals has received little attention. The aim of our study was to estimate the accuracy of source localization of rhythmic ictal EEG activity using a distributed source model.

Methods

Source localization of rhythmic ictal scalp EEG activity was performed in 42 consecutive cases fulfilling inclusion criteria. The study was designed according to recommendations for studies on diagnostic accuracy (STARD). The initial ictal EEG signals were selected using a standardized method, based on frequency analysis and voltage distribution of the ictal activity. A distributed source model—local autoregressive average (LAURA)—was used for the source localization. Sensitivity, specificity, and measurement of agreement (kappa) were determined based on the reference standard—the consensus conclusion of the multidisciplinary epilepsy surgery team. Predictive values were calculated from the surgical outcome of the operated patients. To estimate the clinical value of the ictal source analysis, we compared the likelihood ratios of concordant and discordant results. Source localization was performed blinded to the clinical data, and before the surgical decision.

Key Findings

Reference standard was available for 33 patients. The ictal source localization had a sensitivity of 70% and a specificity of 76%. The mean measurement of agreement (kappa) was 0.61, corresponding to substantial agreement (95% confidence interval (CI) 0.38–0.84). Twenty patients underwent resective surgery. The positive predictive value (PPV) for seizure freedom was 92% and the negative predictive value (NPV) was 43%. The likelihood ratio was nine times higher for the concordant results, as compared with the discordant ones.

Significance

Source localization of rhythmic ictal activity using a distributed source model (LAURA) for the ictal EEG signals selected with a standardized method is feasible in clinical practice and has a good diagnostic accuracy. Our findings encourage clinical neurophysiologists assessing ictal EEGs to include this method in their armamentarium.
Seasonality of North Atlantic phytoplankton from space: impact of environmental forcing on a changing phenology (1998–2012)
Authors: González Taboada Fernando , Anadón Ricardo
Published: August 2013

Seasonal pulses of phytoplankton drive seasonal cycles of carbon fixation and particle sedimentation, and might condition recruitment success in many exploited species. Taking advantage of long‐term series of remotely sensed chlorophyll a (1998–2012), we analyzed changes in phytoplankton seasonality in the North Atlantic Ocean. Phytoplankton phenology was analyzed based on a probabilistic characterization of bloom incidence. This approach allowed us to detect changes in the prevalence of different seasonal cycles and, at the same time, to estimate bloom timing and magnitude taking into account uncertainty in bloom detection. Deviations between different sensors stressed the importance of a prolonged overlap between successive missions to ensure a correct assessment of phenological changes, as well as the advantage of semi‐analytical chlorophyll algorithms over empirical ones to reduce biases. Earlier and more intense blooms were detected in the subpolar Atlantic, while advanced blooms of less magnitude were common in the Subtropical gyre. In the temperate North Atlantic, spring blooms advanced their timing and decreased in magnitude, whereas fall blooms delayed and increased their intensity. At the same time, the prevalence of locations with a single autumn/winter bloom or with a bimodal seasonal cycle increased, in consonance with a poleward expansion of subtropical conditions. Changes in bloom timing and magnitude presented a clear signature of environmental factors, especially wind forcing, although changes on incident photosynthetically active radiation and sea surface temperature were also important depending on latitude. Trends in bloom magnitude matched changes in mean chlorophyll a during the study period, suggesting that seasonal peaks drive long‐term trends in chlorophyll a concentration. Our results link changes in North Atlantic climate with recent trends in the phenology of phytoplankton, suggesting an intensification of these impacts in the near future.
History from Six‐feet Below: Death Studies and the Field of Modern Middle East History
Authors: Minkin Shane
Published: August 2013

This article explores the intersections between scholarship of the nascent field of Death Studies and that of modern Middle East history. Death is both present and absent in the field of modern Middle East history. Death is present in that it is omnipresent; the discipline of history requires an inquiry into the worlds of those who have died, and Middle East scholars have long spoken of death and used the archives of death (e.g. probate courts or death certificates) in their research. However, death is absent in that it usually plays a supporting role and is rarely the primary lens of analysis in Middle East scholarship. This article discusses some of the existing literature, including that of cemeteries, burials and funerals, public health, crime, and legal reform. I argue that increased and conscientious engagement between the fields of Death Studies and modern Middle East history is both possible and productive. Placing death at the center of historical analysis asks questions of power and space, such as who controls the body, where a body might be buried, how a death should be processed, and what impact the dead might have on the various domains of the living. Moreover, it requires the scholar to grapple ideas that cannot be disentwined such as the tangible (e.g. body) and the intangible (e.g. spirituality), or public space and political belonging, in the process of illuminating how the dead continue to make social, spatial, and political claims on the living.
Christian Ritual Magic in the Middle Ages
Authors: Fanger Claire
Published: August 2013

This article gives a brief introduction to the area of medieval ritual magic, outlining the main kinds of texts likely to be understood as belonging to the category – image magic, necromancy, and theurgy or angel magic. Before moving to an overview of the current state of scholarship, it makes note of some watershed works that helped to open up the area of intellectual magic for study. A number of interesting new discoveries, both textual and historical, have been made since the 1990s, and these discoveries have in turn instigated a push toward further exploration and editing of medieval texts and manuscripts of ritual magic, which is turning out to be a more interesting and diverse category than might once have been assumed.
The British Empire, International Government, and Human Rights
Authors: Grant Kevin
Published: August 2013

This essay examines recent publications in several historical fields to articulate the relationships between the British Empire, international government, and human rights from British conceptions of imperial world order in the late nineteenth century to the end of empire in the Cold War.
Managing Transition: Western Britain from the End of Empire to the Rise of Penda
Authors: White Roger
Published: August 2013

The transition of Britain from being a province within the Roman Empire to the Kingdoms of Medieval England is one that is dominated in the public imagination by the historical account written by Bede. This tells us of how the Anglo‐Saxons were invited into Britain, settling in specific territories. This largely accords with the archaeological record. What Bede does not talk of is how the other nations of Britain arose. It is argued that the genesis of the peoples of the West, the Welsh and Cornish, derives from the survival of one of the later Roman provinces of Roman Britain, Britannia Prima. While the other three provinces succumbed swiftly to the incoming Anglo‐Saxon populations that had been invited to defend the territory, in the West Britannia Prima was able to defend itself for a century and a half until Penda began to erode its frontiers. In doing so, it managed to develop and sustain an identity that was no longer Roman but was something new, based on the Brittonic culture of the coastal region of the province and which coalesced into the peoples known today as the Welsh and Cornish.
The Emergence of the Territorial Principality of Flanders, 750–1050
Authors: Defries David
Published: August 2013

The historiography of the early territorial principality of Flanders rests on two foundation layers. The first layer establishes a narrative for the Baldwinid dynasty (r. 864–1119) of Flemish counts, who cobbled together a strong principality across what is now the southern Netherlands, Belgium and northeastern France. The narrative in turn rests on a conceptual layer associated with political historiography about France, represented by scholars such as François‐Louis Ganshof and Jan Dhondt. This school posits a decline in the authority of the West Frankish kings as a result of usurpations by magnates. While the basic narrative of the principality's origins has remained essentially unchanged since the 1940s, the conceptual ground has shifted underneath it. This article surveys the conceptual framework and challenges to the francophone school, then outlines the narrative historiography of early Flanders. It argues there is a pressing need for a reassessment of the Flemish principality's emergence in light of new theories of Carolingian royal power.
A current perspective on the pathological assessment of FOXL2 in adult‐type granulosa cell tumours of the ovary
Authors: Kommoss Stefan , Gilks Cyril Blake , Penzel Roland , Herpel Esther , Mackenzie Robertson , Huntsman David , Schirmacher Peter , Anglesio Michael , Schmidt Dietmar , Kommoss Friedrich
Published: August 2013

Aims

The diagnosis of adult‐type granulosa cell tumours of the ovary (aGCT) is based on histomorphology aided by immunohistochemical staining for sex cord markers. Recently a single, recurrent somatic point mutation (402C→G) in FOXL2 was described in aGCT. We have investigated the impact of FOXL2 mutation testing in a large cohort of aGCT diagnosed previously by conventional histology and immunohistochemistry.

Methods and results

Formalin‐fixed, paraffin‐embedded tissue cores from a cohort of 52 aGCT diagnosed previously by expert gynaecopathologists were analysed immunohistologically. FOXL2 mutation status was determined by Sanger sequencing and high‐sensitivity TaqMan allelic discrimination assay. Histomorphology was reassessed by two expert gynaecopathologists. FOXL2 mutation analyses could be performed successfully in 46 cases, 40 of which were positive for the c.402C>G mutation, confirming a diagnosis of aGCT. In the six cases negative for the c.402C>G mutation, one case was confirmed on review as FOXL2 wild‐type aGCT, whereas in the remaining five cases diagnoses other than aGCT were made.

Conclusion

In cases where a diagnosis of aGCT is a consideration and unequivocal diagnosis is not possible based on morphology and routine immunostains, FOXL2 mutation testing can help to confirm the diagnosis. It is particularly relevant for accurate subclassification within the group of sex cord–stromal tumours.