Improving bioscience research reporting: the ARRIVE guidelines for reporting animal research

Replicated, replicable and relevant-target engagement and pharmacological experimentation in the 21st century

A pharmacological experiment is typically conducted to: i) test or expand a hypothesis regarding the potential role of a target in the mechanism(s) underlying a disease state using an existing drug or tool compound in normal and/or diseased tissue or animals; or ii) characterize and optimize a new chemical entity (NCE) targeted to modulate a specific disease-associated target to restore homeostasis as a potential drug candidate. Hypothesis testing necessitates an intellectually rigorous, null hypothesis approach that is distinct from a high throughput fishing expedition in search of a hypothesis. In conducting an experiment, the protocol should be transparently defined along with its powering, design, appropriate statistical analysis and consideration of the anticipated outcome (s) before it is initiated. Compound-target interactions often involve the direct study of phenotype(s) unique to the target at the cell, tissue or animal/human level. However, in vivo studies are often compromised by a lack of sufficient information on the compound pharmacokinetics necessary to ensure target engagement and also by the context-free analysis of ubiquitous cellular signaling pathways downstream from the target. The use of single tool compounds/drugs at one concentration in engineered cell lines frequently results in reductionistic data that have no physiologically relevance. This overview, focused on trends in the peer-reviewed literature, discusses the execution and reporting of experiments and the criteria recommended for the physiologically-relevant assessment of target engagement to identify viable new drug targets and facilitate the advancement of translational studies.

Selective ROCK2 Inhibition In Focal Cerebral Ischemia

OBJECTIVE

Rho-associated kinase (ROCK) is a key regulator of numerous processes in multiple cell types relevant in stroke pathophysiology. ROCK inhibitors have improved outcome in experimental models of acute ischemic or hemorrhagic stroke. However, the relevant ROCK isoform (ROCK1 or ROCK2) in acute stroke is not known.

METHODS

We characterized the pharmacodynamic and pharmacokinetic profile, and tested the efficacy and safety of a novel selective ROCK2 inhibitor KD025 (formerly SLx-2119) in focal cerebral ischemia models in mice.

RESULTS

KD025 dose-dependently reduced infarct volume after transient middle cerebral artery occlusion. The therapeutic window was at least 3 hours from stroke onset, and the efficacy was sustained for at least 4 weeks. KD025 was at least as efficacious in aged, diabetic or female mice, as in normal adult males. Concurrent treatment with atorvastatin was safe, but not additive or synergistic. KD025 was also safe in a permanent ischemia model, albeit with diminished efficacy. As one mechanism of protection, KD025 improved cortical perfusion in a distal middle cerebral artery occlusion model, implicating enhanced collateral flow. Unlike isoform-nonselective ROCK inhibitors, KD025 did not cause significant hypotension, a dose-limiting side effect in acute ischemic stroke.

INTERPRETATION

Altogether, these data show that KD025 is efficacious and safe in acute focal cerebral ischemia in mice, implicating ROCK2 as the relevant isoform in acute ischemic stroke. Data suggest that selective ROCK2 inhibition has a favorable safety profile to facilitate clinical translation.

Behaviour of a new composite mesh for the repair of full-thickness abdominal wall defects in a rabbit model

Introduction

Composite biomaterials designed for the repair of abdominal wall defects are composed of a mesh component and a laminar barrier in contact with the visceral peritoneum. This study assesses the behaviour of a new composite mesh by comparing it with two latest-generation composites currently used in clinical practice.

Methods

Defects (7x5cm) created in the anterior abdominal wall of New Zealand White rabbits were repaired using a polypropylene mesh and the composites: Physiomesh^TM; Ventralight^TM and a new composite mesh with a three-dimensional macroporous polyester structure and an oxidized collagen/chitosan barrier. Animals were sacrificed on days 14 and 90 postimplant. Specimens were processed to determine host tissue incorporation, gene/protein expression of neo-collagens (RT-PCR/immunofluorescence), macrophage response (RAM-11-immunolabelling) and biomechanical resistance. On postoperative days 7/14, each animal was examined laparoscopically to quantify adhesions between the visceral peritoneum and implant.

Results

The new composite mesh showed the lowest incidence of seroma in the short term. At each time point, the mesh surface covered with adhesions was greater in controls than composites. By day 14, the implants were fully infiltrated by a loose connective tissue that became denser over time. At 90 days, the peritoneal mesh surface was lined with a stable mesothelium. The new composite mesh induced more rapid tissue maturation than Physiomesh^TM, giving rise to a neoformed tissue containing more type I collagen. In Ventralight^TM the macrophage reaction was intense and significantly greater than the other composites at both follow-up times. Tensile strengths were similar for each biomaterial.

Conclusions

All composites showed optimal peritoneal behaviour, inducing good peritoneal regeneration and scarce postoperative adhesion formation. A greater foreign body reaction was observed for Ventralight^TM. All composites induced good collagen deposition accompanied by optimal tensile strength. The three-dimensional macroporous structure of the new composite mesh may promote rapid tissue regeneration within the mesh.

Synaptic activity bidirectionally regulates a novel sequence-specific S-Q phosphoproteome in neurons

Protein phosphorylation plays a critical role in neuronal transcription, translation, cell viability, and synaptic plasticity. In neurons, phospho-enzymes and specific substrates directly link glutamate release and post-synaptic depolarization to these cellular functions; however, many of these enzymes and their protein substrates remain uncharacterized or unidentified. In this article, we identify a novel, synaptically driven neuronal phosphoproteome characterized by a specific motif of serine/threonine-glutamine ([S/T]-Q, abbreviated as SQ). These SQ-containing substrates are predominantly localized to dendrites, synapses, the soma; and activation of this SQ phosphoproteome by bicuculline application is induced via calcium influx through L-type calcium channels. On the other hand, acute application of NMDA can inactivate this SQ phosphoproteome. We demonstrate that the SQ motif kinase Ataxia-telangiectasia mutated can also localize to dendrites and dendritic spines, in addition to other subcellular compartments, and is activated by bicuculline application. Pharmacology studies indicate that Ataxia-telangiectasia mutated and its sister kinase ataxia telangiectasia mutated and Rad3-related up-regulate these neuronal SQ substrates. Phosphoproteomics identified over 150 SQ-containing substrates whose phosphorylation is bidirectionally regulated by synaptic activity.

Catheter-based renal sympathetic denervation significantly inhibits atrial fibrillation induced by electrical stimulation of the left stellate ganglion and rapid atrial pacing

Background

Sympathetic activity involves the pathogenesis of atrial fibrillation (AF). Renal sympathetic denervation (RSD) decreases sympathetic renal afferent nerve activity, leading to decreased central sympathetic drive. The aim of this study was to identify the effects of RSD on AF inducibility induced by hyper-sympathetic activity in a canine model.

Methods

To establish a hyper-sympathetic tone canine model of AF, sixteen dogs were subjected to stimulation of left stellate ganglion (LSG) and rapid atrial pacing (RAP) for 3 hours. Then animals in the RSD group (n = 8) underwent radiofrequency ablation of the renal sympathetic nerve. The control group (n = 8) underwent the same procedure except for ablation. AF inducibility, effective refractory period (ERP), ERP dispersion, heart rate variability and plasma norepinephrine levels were measured at baseline, after stimulation and after ablation.

Results

LSG stimulation combined RAP significantly induced higher AF induction rate, shorter ERP, larger ERP dispersion at all sites examined and higher plasma norepinephrine levels (P<0.05 in all values), compared to baseline. The increased AF induction rate, shortened ERP, increased ERP dispersion and elevated plasma norepinephrine levels can be almost reversed by RSD, compared to the control group (P<0.05). LSG stimulation combined RAP markedly shortened RR-interval and standard deviation of all RR-intervals (SDNN), Low-frequency (LF), high-frequency (HF) and LF/HF ratio (P<0.05). These changes can be reversed by RSD, compared to the control group (P<0.05).

Conclusions

RSD significantly reduced AF inducibility and reversed the atrial electrophysiological changes induced by hyper-sympathetic activity.

13C-isotope-based protocol for prenyl lipid metabolic analysis in zebrafish embryos

Metabolism has a decisive role in many fundamental biological processes, including organism development and tissue homeostasis. Here we describe a protocol for fast and reliable (13)C-isotope-based in vivo metabolic profiling. This protocol covers the loading of isotope precursor; extraction, preparation and quantification of the labeled lipid metabolites (e.g., the prenyl lipid CoQ10) by the means of HPLC-MS; and its analysis in zebrafish embryos. This protocol can be applied to different types of experimental settings, including tissue-specific metabolic analyses or dynamic metabolic changes that occur during vertebrate embryogenesis. The protocol takes 5-7 d to complete, requiring minimal equipment and analytical expertise, and it represents a unique alternative to the existing ex vivo (e.g., cell lines) isotope-based metabolic methods. This procedure represents a valuable approach for researchers interested in studying the effect of gene manipulation on lipid metabolism in zebrafish and in understanding the genetic conditions that result in metabolism dysfunction.

Factors influencing arthrodesis rates in a rabbit posterolateral spine model with iliac crest autograft

PURPOSE

The rabbit posterolateral intertransverse spine arthrodesis model has been widely used to evaluate spinal biologics. However, to date, the validity and reproducibility of performance of iliac crest bone graft, the most common and critical control group, has not been firmly established. We evaluated original research publications that utilized this model, identified which experimental conditions affected fusion rates, and developed an algorithm to predict fusion rates for future study designs.

METHODS

A MEDLINE search was performed for publications through December, 2011 that utilized this model to evaluate fusion rates elicited by iliac crest autograft. All study parameters were recorded, and logistic regression analyses were performed to determine the effects of these variables on fusion rates as determined by either manual palpation or radiographs.

RESULTS

Seventy studies with 959 rabbits in 102 groups met the inclusion criteria. Excluding studies that measured fusion at 4 or fewer weeks or intentionally tried to decrease the fusion rate, the overall fusion rate for autograft was 58.3 ± 16.3 % (mean ± SD) as determined by manual palpation and 66.4 ± 17.8 % by plain radiographs. Regression analysis demonstrated a difference between these outcome measures with a trend towards significance (p = 0.09). Longer time points and larger volumes of autograft resulted in significantly greater reported fusion rates (p < 0.0001 and p < 0.05, respectively). Neither strain, age, weight, nor vertebral level significantly affected fusion rates.

CONCLUSIONS

Although experimental conditions varied across studies, time point evaluation and autograft volume significantly affected fusion rates. Despite some variability demonstrated across certain studies, we demonstrated that when the time point and volume of autograft were controlled for, the iliac crest control group of the rabbit posterolateral spinal arthrodesis model is both reliable and predictably affected by different experimental conditions.

Growth reaction norms of domesticated, wild and hybrid Atlantic salmon families in response to differing social and physical environments

Background

Directional selection for growth has resulted in the 9-10th generation of domesticated Atlantic salmon Salmo salar L. outgrowing wild salmon by a ratio of approximately 3:1 when reared under standard hatchery conditions. In the wild however, growth of domesticated and wild salmon is more similar, and seems to differ at the most by a ratio of 1.25:1. Comparative studies of quantitative traits in farmed and wild salmon are often performed by the use of common-garden experiments where salmon of all origins are reared together to avoid origin-specific environmental differences. As social interaction may influence growth, the large observed difference in growth between wild and domesticated salmon in the hatchery may not be entirely genetically based, but inflated by inter-strain competition. This study had two primary aims: (i) investigate the effect of social interaction and inter-strain competition in common-garden experiments, by comparing the relative growth of farmed, hybrid and wild salmon when reared together and separately; (ii) investigate the competitive balance between wild and farmed salmon by comparing their norm of reaction for survival and growth along an environmental gradient ranging from standard hatchery conditions to a semi-natural environment with restricted feed.

Results

The main results of this study, which are based upon the analysis of more than 6000 juvenile salmon, can be summarised as; (i) there was no difference in relative growth between wild and farmed salmon when reared together and separately; (ii) the relative difference in body weight at termination between wild and farmed salmon decreased as mortality increased along the environmental gradient approaching natural conditions.

Conclusions

This study demonstrates that potential social interactions between wild and farmed salmon when reared communally are not likely to cause an overestimation of the genetic growth differences between them. Therefore, common-garden experiments represent a valid methodological approach to investigate genetic differences between wild and farmed salmon. As growth of surviving salmon of all origins became more similar as mortality increased along the environmental gradient approaching natural conditions, a hypothesis is presented suggesting that size-selective mortality is a possible factor reducing growth differences between these groups in the wild.

KIBRA (KIdney/BRAin protein) regulates learning and memory and stabilizes Protein kinase Mζ

The WWC1 gene has been genetically associated with human episodic memory performance, and its product KIdney/BRAin protein (KIBRA) has been shown to interact with the atypical protein kinase protein kinase M ζ (PKMζ). Although recently challenged, PKMζ remains a candidate postsynaptic regulator of memory maintenance. Here, we show that PKMζ is subject to rapid proteasomal degradation and that KIBRA is both necessary and sufficient to counteract this process, thus stabilizing the kinase and maintaining its function for a prolonged time. We define the binding sequence on KIBRA, a short amino acid motif near the C-terminus. Both hippocampal knock-down of KIBRA in rats and KIBRA knock-out in mice result in decreased learning and memory performance in spatial memory tasks supporting the notion that KIBRA is a player in episodic memory. Interestingly, decreased memory performance is accompanied by decreased PKMζ protein levels. We speculate that the stabilization of synaptic PKMζ protein levels by KIBRA may be one mechanism by which KIBRA acts in memory maintenance. KIBRA/WWC1 has been genetically associated with human episodic memory. KIBRA has been shown to be post-synaptically localized, but its function remained obscure. Here, we show that KIBRA shields PKMζ, a kinase previously linked to memory maintenance, from proteasomal degradation via direct interaction. KIBRA levels in the rodent hippocampus correlate closely both to spatial memory performance in rodents and to PKMζ levels. Our findings support a role for KIBRA in memory, and unveil a novel function for this protein.

3:1 compression to ventilation ratio versus continuous chest compression with asynchronous ventilation in a porcine model of neonatal resuscitation

OBJECTIVE

In contrast to the resuscitation guidelines of children and adults, guidelines on neonatal resuscitation recommend synchronized 90 chest compressions with 30 manual inflations (3:1) per minute in newborn infants. The study aimed to determine if chest compression with asynchronous ventilation improves the recovery of bradycardic asphyxiated newborn piglets compared to 3:1 Compression:Ventilation cardiopulmonary resuscitation (CPR).

INTERVENTION AND MEASUREMENTS

Term newborn piglets (n=8/group) were anesthetized, intubated, instrumented and exposed to 45-min normocapnic hypoxia followed by asphyxia. Protocolized resuscitation was initiated when heart rate decreased to 25% of baseline. Piglets were randomized to receive resuscitation with either 3:1 compressions to ventilations (3:1C:V CPR group) or chest compressions with asynchronous ventilations (CCaV) or sham. Continuous respiratory parameters (Respironics NM3(®)), cardiac output, mean systemic and pulmonary artery pressures, and regional blood flows were measured.

MAIN RESULTS

Piglets in 3:1C:V CPR and CCaV CPR groups had similar time to return of spontaneous circulation, survival rates, hemodynamic and respiratory parameters during CPR. The systemic and regional hemodynamic recovery in the subsequent 4h was similar in both groups and significantly lower compared to sham-operated piglets.

CONCLUSION

Newborn piglets resuscitated by CCaV had similar return of spontaneous circulation, survival, and hemodynamic recovery compared to those piglets resuscitated by 3:1 Compression:Ventilation ratio.

Steroid-associated hip joint collapse in bipedal emus

In this study we established a bipedal animal model of steroid-associated hip joint collapse in emus for testing potential treatment protocols to be developed for prevention of steroid-associated joint collapse in preclinical settings. Five adult male emus were treated with a steroid-associated osteonecrosis (SAON) induction protocol using combination of pulsed lipopolysaccharide (LPS) and methylprednisolone (MPS). Additional three emus were used as normal control. Post-induction, emu gait was observed, magnetic resonance imaging (MRI) was performed, and blood was collected for routine examination, including testing blood coagulation and lipid metabolism. Emus were sacrificed at week 24 post-induction, bilateral femora were collected for micro-computed tomography (micro-CT) and histological analysis. Asymmetric limping gait and abnormal MRI signals were found in steroid-treated emus. SAON was found in all emus with a joint collapse incidence of 70%. The percentage of neutrophils (Neut %) and parameters on lipid metabolism significantly increased after induction. Micro-CT revealed structure deterioration of subchondral trabecular bone. Histomorphometry showed larger fat cell fraction and size, thinning of subchondral plate and cartilage layer, smaller osteoblast perimeter percentage and less blood vessels distributed at collapsed region in SAON group as compared with the normal controls. Scanning electron microscope (SEM) showed poor mineral matrix and more osteo-lacunae outline in the collapsed region in SAON group. The combination of pulsed LPS and MPS developed in the current study was safe and effective to induce SAON and deterioration of subchondral bone in bipedal emus with subsequent femoral head collapse, a typical clinical feature observed in patients under pulsed steroid treatment. In conclusion, bipedal emus could be used as an effective preclinical experimental model to evaluate potential treatment protocols to be developed for prevention of ON-induced hip joint collapse in patients.

Do major roads reduce gene flow in urban bird populations?

BACKGROUND

Although the negative effects of roads on the genetics of animal populations have been extensively reported, the question of whether roads reduce gene flow in volant, urban bird populations has so far not been addressed. In this study, we assess whether highways decreased gene flow and genetic variation in a small passerine bird, the tree sparrow (Passer montanus).

METHODOLOGY

We assessed genetic differences among tree sparrows (Passer montanus) sampled at 19 sites within Beijing Municipality, China, using 7 DNA microsatellites as genetic markers.

RESULTS

AMOVA showed that genetic variation between sites, between urban and rural populations, and between opposite sides of the same highway, were very weak. Mantel tests on all samples, and on urban samples only, indicated that the age and number of highways, and the number of ordinary roads, were uncorrelated with genetic differences (F ST) among tree sparrows from different urban sites. Birds sampled at urban sites had similar levels of genetic diversity to those at rural sites. There was, however, evidence of some weak genetic structure between urban sites. Firstly, there were significant genetic differences (F ST) between birds from opposite sides of the same highway, but no significant F ST values between those from sites that were not separated by highways. Secondly, birds from eleven urban sites had loci that significantly deviated from the Hardy-Weinberg equilibrium but no such deviation was found in birds from rural sites.

CONCLUSION

We cannot, therefore, conclusively reject the hypothesis that highways have no effect on the gene flow of tree sparrow populations. Furthermore, since the significance of these results may increase with time, we suggested that research on the influence of highways on gene flow in urban bird populations needs to be conducted over several decades.

Issues related to development of antiepileptogenic therapies

Several preclinical proof-of-concept studies have provided evidence for positive treatment effects on epileptogenesis. However, none of these hypothetical treatments has advanced to the clinic. The experience in other fields of neurology such as stroke, Alzheimer's disease, or amyotrophic lateral sclerosis has indicated several problems in the design of preclinical studies, which likely contribute to failures in translating the positive preclinical data to the clinic. The Working Group on "Issues related to development of antiepileptogenic therapies" of the International League Against Epilepsy (ILAE) and the American Epilepsy Society (AES) has considered the possible problems that arise when moving from proof-of-concept antiepileptogenesis (AEG) studies to preclinical AEG trials, and eventually to clinical AEG trials. This article summarizes the discussions and provides recommendations on how to design a preclinical AEG monotherapy trial in adult animals. We specifically address study design, animal and model selection, number of studies needed, issues related to administration of the treatment, outcome measures, statistics, and reporting. In addition, we give recommendations for future actions to advance the preclinical AEG testing.

Epilepsy therapy development: technical and methodologic issues in studies with animal models

The search for new treatments for seizures, epilepsies, and their comorbidities faces considerable challenges. This is due in part to gaps in our understanding of the etiology and pathophysiology of most forms of epilepsy. An additional challenge is the difficulty in predicting the efficacy, tolerability, and impact of potential new treatments on epilepsies and comorbidities in humans, using the available resources. Herein we provide a summary of the discussions and proposals of the Working Group 2 as presented in the Joint American Epilepsy Society and International League Against Epilepsy Translational Workshop in London (September 2012). We propose methodologic and reporting practices that will enhance the uniformity, reliability, and reporting of early stage preclinical studies with animal seizure and epilepsy models that aim to develop and evaluate new therapies for seizures or epilepsies, using multidisciplinary approaches. The topics considered include the following: (1) implementation of better study design and reporting practices; (2) incorporation in the study design and analysis of covariants that may influence outcomes (including species, age, sex); (3) utilization of approaches to document target relevance, exposure, and engagement by the tested treatment; (4) utilization of clinically relevant treatment protocols; (5) optimization of the use of video-electroencephalography (EEG) recordings to best meet the study goals; and (6) inclusion of outcome measures that address the tolerability of the treatment or study end points apart from seizures. We further discuss the different expectations for studies aiming to meet regulatory requirements to obtain approval for clinical testing in humans. Implementation of the rigorous practices discussed in this report will require considerable investment in time, funds, and other research resources, which may create challenges for academic researchers seeking to contribute to epilepsy therapy discovery and development. We propose several infrastructure initiatives to overcome these barriers.

Wild-type but not mutant SOD1 transgenic astrocytes promote the efficient generation of motor neuron progenitors from mouse embryonic stem cells

Background

The efficient derivation of mature (Hb9+) motor neurons from embryonic stem cells is a sought-after goal in the understanding, and potential treatment, of motor neuron diseases. Conditions that promote the robust generation of motor neuron progenitors from embryonic stem cells and that promote the survival of differentiated motor neurons ex vivo are likely, therefore, to be critical in future biological/therapeutic/screening approaches. Previous studies have shown that astrocytes have a protective effect on differentiated motor neurons (in vivo and ex vivo), but it remains unclear whether astrocytes also play a beneficial role in the support of motor neuron progenitors. Here we explore the effect of murine astrocyte-conditioned medium on monolayer cultures of mouse embryonic stem cell-derived motor neuron progenitors.

Results

Our data show that wild-type astrocyte-conditioned medium significantly increases the number of Olig2+/Hb9- progenitors, which subsequently differentiate into Hb9+/Islet1+ post-mitotic motor neurons. Intriguingly, while astrocyte-conditioned medium derived from mice transgenic for wild-type human SOD1 mimics the effect of wild-type astrocytes, conditioned medium derived from astrocytes carrying an amyotrophic lateral sclerosis-related SOD1-G93A mutation shows no such beneficial effect. The effect of astrocyte-conditioned medium, moreover, is specific to motor neurons: we find that interneurons generated from mouse embryonic stem cells are unaffected by conditioned media from any type of astrocyte.

Conclusions

Our study indicates that conditioned medium derived from wild type astrocytes enhances the efficient generation of motor neurons from mouse embryonic stem cells by enhancing motor neuron progenitors. In contrast, conditioned medium from SOD1-G93A astrocytes does not show a similar enhancing effect.

Experimental liver fibrosis research: update on animal models, legal issues and translational aspects

Liver fibrosis is defined as excessive extracellular matrix deposition and is based on complex interactions between matrix-producing hepatic stellate cells and an abundance of liver-resident and infiltrating cells. Investigation of these processes requires in vitro and in vivo experimental work in animals. However, the use of animals in translational research will be increasingly challenged, at least in countries of the European Union, because of the adoption of new animal welfare rules in 2013. These rules will create an urgent need for optimized standard operating procedures regarding animal experimentation and improved international communication in the liver fibrosis community. This review gives an update on current animal models, techniques and underlying pathomechanisms with the aim of fostering a critical discussion of the limitations and potential of up-to-date animal experimentation. We discuss potential complications in experimental liver fibrosis and provide examples of how the findings of studies in which these models are used can be translated to human disease and therapy. In this review, we want to motivate the international community to design more standardized animal models which might help to address the legally requested replacement, refinement and reduction of animals in fibrosis research.

Transgene delivery to endothelial cultures derived from porcine carotid artery ex vivo

Carotid artery disease is a widespread cause of morbidity and mortality. Porcine models of vascular disease are well established in vivo, but existing endothelial systems in vitro (e.g. human umbilical vein endothelial cells, rat aortic endothelial cultures) poorly reflect carotid endothelium. A reliable in vitro assay would improve design of in vivo experiments and allow reduction and refinement of animal use. This study aimed (1) to develop ex vivo endothelial cultures from porcine carotid and (2) to test whether these were suitable for lentivector-mediated transgene delivery. Surplus carotid arteries were harvested from young adult female Large White pigs within 10 min post-mortem. Small sectors of carotid artery wall (approximately 4 mm×4 mm squares) were immobilised in a stable gel matrix. Cultures were exposed to HIV-derived lentivector (LV) encoding a reporter transgene or the equivalent integration-deficient vector (IDLV). After 7-14 days in vitro, cultures were fixed and labelled histochemically. Thread-like multicellular outgrowths were observed that were positive for endothelial cell markers (CD31, VEGFR2, von Willebrand factor). A minority of cells co-labelled for smooth muscle markers. Sensitivity to cytotoxic agents (paclitaxel, cycloheximide, staurosporine) was comparable to that in cell cultures, indicating that the gel matrix permits diffusive access of small pharmacological molecules. Transgene-expressing cells were more abundant following exposure to LV than IDLV (4.7, 0.1% of cells, respectively). In conclusion, ex vivo adult porcine carotid artery produced endothelial cell outgrowths that were effectively transduced by LV. This system will facilitate translation of novel therapies to clinical trials, with reduction and refinement of in vivo experiments.

Decreased in vitro mitochondrial function is associated with enhanced brain metabolism, blood flow, and memory in Surf1-deficient mice

Recent studies have challenged the prevailing view that reduced mitochondrial function and increased oxidative stress are correlated with reduced longevity. Mice carrying a homozygous knockout (KO) of the Surf1 gene showed a significant decrease in mitochondrial electron transport chain Complex IV activity, yet displayed increased lifespan and reduced brain damage after excitotoxic insults. In the present study, we examined brain metabolism, brain hemodynamics, and memory of Surf1 KO mice using in vitro measures of mitochondrial function, in vivo neuroimaging, and behavioral testing. We show that decreased respiration and increased generation of hydrogen peroxide in isolated Surf1 KO brain mitochondria are associated with increased brain glucose metabolism, cerebral blood flow, and lactate levels, and with enhanced memory in Surf1 KO mice. These metabolic and functional changes in Surf1 KO brains were accompanied by higher levels of hypoxia-inducible factor 1 alpha, and by increases in the activated form of cyclic AMP response element-binding factor, which is integral to memory formation. These findings suggest that Surf1 deficiency-induced metabolic alterations may have positive effects on brain function. Exploring the relationship between mitochondrial activity, oxidative stress, and brain function will enhance our understanding of cognitive aging and of age-related neurologic disorders.

Plasma proteome profiles associated with diet-induced metabolic syndrome and the early onset of metabolic syndrome in a pig model

Obesity and related diabetes are important health threatening multifactorial metabolic diseases and it has been suggested that 25% of all diabetic patients are unaware of their patho-physiological condition. Biomarkers for monitoring and control are available, but early stage predictive biomarkers enabling prevention of these diseases are still lacking. We used the pig as a model to study metabolic disease because humans and pigs share a multitude of metabolic similarities. Diabetes was chemically induced and control and diabetic pigs were either fed a high unsaturated fat (Mediterranean) diet or a high saturated fat/cholesterol/sugar (cafeteria) diet. Physiological parameters related to fat metabolism and diabetes were measured. Diabetic pigs' plasma proteome profiles differed more between the two diets than control pigs plasma proteome profiles. The expression levels of several proteins correlated well with (patho)physiological parameters related to the fat metabolism (cholesterol, VLDL, LDL, NEFA) and diabetes (Glucose) and to the diet fed to the animals. Studying only the control pigs as a model for metabolic syndrome when fed the two diets showed correlations to the same parameters but now more focused on insulin, glucose and abdominal fat depot parameters. We conclude that proteomic profiles can be used as a biomarker to identify pigs with developing metabolic syndrome (prediabetes) and diabetes when fed a cafeteria diet. It could be developed into a potential biomarkers for the early recognition of metabolic diseases.

Issues of reporting in observational studies in veterinary medicine

Observational studies are common in veterinary medicine; the results may be used to inform decision-making, future research, or as inputs to systematic reviews or risk assessment. To be of use, the results must be published, all of the outcomes that were assessed must be included in the publication, and the research (methods and results) must be reported in sufficient detail that the reader can evaluate the internal and external validity. In human healthcare, concerns about the completeness of reporting - and evidence that poor reporting is associated with study results - have led to the creation of reporting guidelines; these include the STROBE statement for observational studies. There is evidence from a limited body of research that there also are reporting inadequacies in veterinary observational studies. There are differences between human and veterinary observational studies that might be relevant to recommendations for reporting. Such differences include: the use of observational studies in animal populations for simultaneously estimating disease frequency and risk-factor identification; the distinction between the animal owners who consent to participate and the animals that are the study subjects; and the complexity of organizational levels inherent in animal research (in particular, for studies in livestock species). In veterinary medicine, it is common to have clustering within outcomes (due to animal grouping) and clustering of predictor variables. We argue that there is a compelling need for the scientific community involved in veterinary observational studies to use the STROBE statement, use an amended version of STROBE, or to develop and use reporting guidelines that are specific to veterinary medicine to improve reporting of these studies.

Pain fiber anesthetic reduces brainstem Fos after tooth extraction

We recently demonstrated that pain-sensing neurons in the trigeminal system can be selectively anesthetized by co-application of QX-314 with the TRPV1 receptor agonist, capsaicin (QX cocktail). Here we examined whether this new anesthetic strategy can block the neuronal changes in the brainstem following molar tooth extraction in the rat. Adult male Sprague-Dawley rats received infiltration injection of anesthetic 10 min prior to lower molar tooth extraction. Neuronal activation was determined by immunohistochemistry for the proto-oncogene protein c-Fos in transverse sections of the trigeminal subnucleus caudalis (Sp5C). After tooth extraction, c-Fos-like immunoreactivity (Fos-LI) detected in the dorsomedial region of bilateral Sp5C was highest at 2 hrs (p < .01 vs. naïve ipsilateral) and declined to pre-injury levels by 8 hrs. Pre-administration of the QX cocktail significantly reduced to sham levels Fos-LI examined 2 hrs after tooth extraction; reduced Fos-LI was also observed with the conventional local anesthetic lidocaine. Pulpal anesthesia by infiltration injection was confirmed by inhibition of the jaw-opening reflex in response to electrical tooth pulp stimulation. Our results suggest that the QX cocktail anesthetic is effective in reducing neuronal activation following tooth extraction. Thus, a selective pain fiber 'nociceptive anesthetic' strategy may provide an effective local anesthetic option for dental patients in the clinic.

Desorption electrospray ionization mass spectrometry reveals lipid metabolism of individual oocytes and embryos

Alteration of maternal lipid metabolism early in development has been shown to trigger obesity, insulin resistance, type 2 diabetes and cardiovascular diseases later in life in humans and animal models. Here, we set out to determine (i) lipid composition dynamics in single oocytes and preimplantation embryos by high mass resolution desorption electrospray ionization mass spectrometry (DESI-MS), using the bovine species as biological model, (ii) the metabolically most relevant lipid compounds by multivariate data analysis and (iii) lipid upstream metabolism by quantitative real-time PCR (qRT-PCR) analysis of several target genes (ACAT1, CPT 1b, FASN, SREBP1 and SCAP). Bovine oocytes and blastocysts were individually analyzed by DESI-MS in both positive and negative ion modes, without lipid extraction and under ambient conditions, and were profiled for free fatty acids (FFA), phospholipids (PL), cholesterol-related molecules, and triacylglycerols (TAG). Principal component analysis (PCA) and linear discriminant analysis (LDA), performed for the first time on DESI-MS fused data, allowed unequivocal discrimination between oocytes and blastocysts based on specific lipid profiles. This analytical approach resulted in broad and detailed lipid annotation of single oocytes and blastocysts. Results of DESI-MS and transcript regulation analysis demonstrate that blastocysts produced in vitro and their in vivo counterparts differed significantly in the homeostasis of cholesterol and FFA metabolism. These results should assist in the production of viable and healthy embryos by elucidating in vivo embryonic lipid metabolism.

Human umbilical cord blood mononuclear cells in a double-hit model of bronchopulmonary dysplasia in neonatal mice

Background

Bronchopulmonary dysplasia (BPD) presents a major threat of very preterm birth and treatment options are still limited. Stem cells from different sources have been used successfully in experimental BPD, induced by postnatal hyperoxia.

Objectives

We investigated the effect of umbilical cord blood mononuclear cells (MNCs) in a new double-hit mouse model of BPD.

Methods

For the double-hit, date mated mice were subjected to hypoxia and thereafter the offspring was exposed to hyperoxia. Human umbilical cord blood MNCs were given intraperitoneally by day P7. As outcome variables were defined: physical development (auxology), lung structure (histomorphometry), expression of markers for lung maturation and inflammation on mRNA and protein level. Pre- and postnatal normoxic pups and sham treated double-hit pups served as control groups.

Results

Compared to normoxic controls, sham treated double-hit animals showed impaired physical and lung development with reduced alveolarization and increased thickness of septa. Electron microscopy revealed reduced volume density of lamellar bodies. Pulmonary expression of mRNA for surfactant proteins B and C, Mtor and Crabp1 was reduced. Expression of Igf1 was increased. Treatment with umbilical cord blood MNCs normalized thickness of septa and mRNA expression of Mtor to levels of normoxic controls. Tgfb3 mRNA expression and pro-inflammatory IL-1β protein concentration were decreased.

Conclusion

The results of our study demonstrate the therapeutic potential of umbilical cord blood MNCs in a new double-hit model of BPD in newborn mice. We found improved lung structure and effects on molecular level. Further studies are needed to address the role of systemic administration of MNCs in experimental BPD.

Multimodal exercises simultaneously stimulating cortical and brainstem pathways after unilateral corticospinal lesion

In the context of injury to the corticospinal tract (CST), brainstem-origin circuits may provide an alternative system of descending motor influence. However, subcortical circuits are largely under subconscious control. To improve volitional control over spared fibers after CST injury, we hypothesized that a combination of physical exercises simultaneously stimulating cortical and brainstem pathways above the injury would strengthen corticobulbar connections through Hebbian-like mechanisms. We sought to test this hypothesis in mice with unilateral CST lesions. Ten days after pyramidotomy, mice were randomized to four training groups: (1) postural exercises designed to stimulate brainstem pathways (BS); (2) distal limb-grip exercises preferentially stimulating CST pathways (CST); (3) simultaneous multimodal exercises (BS+CST); or (4) no training (NT). Behavioral and anatomical outcomes were assessed after 20 training sessions over 4 weeks. Mice in the BS+CST training group showed a trend toward greater improvements in skilled limb performance than mice in the other groups. There were no consistent differences between training groups in gait kinematics. Anatomically, multimodal BS+CST training neither increased corticobulbar fiber density of the lesioned CST rostral to the lesion nor collateral sprouting of the unlesioned CST caudal to the lesion. Further studies should incorporate electrophysiological assessment to gauge changes in synaptic strength of direct and indirect pathways between the cortex and spinal cord in response to multimodal exercises.

MiR-499 regulates cell proliferation and apoptosis during late-stage cardiac differentiation via Sox6 and cyclin D1

Background

MiR-499 is a cardiac-abundant miRNA. However, the biological functions of miR-499 in differentiated cardiomyocytes or in the cardiomyocyte differentiation process is not very clear. Sox6 is believed to be one of its targets, and is also believed to play a role in cardiac differentiation. Therefore, our aim was to investigate the association between Sox6 and miR-499 during cardiac differentiation.

Methodology/Principal Findings

Using a well-established invitro cardiomyocyte differentiation system, mouse P19CL6 cells, we found that miR-499 was highly expressed in the late stage of cardiac differentiation. In cells stably transfected with miR-499 (P-499 cells), it was found that miR-499 could promote the differentiation into cardiomyocytes at the early stage of cardiac differentiation. Notably, cell viability assay, EdU incorporation assay, and cell cycle profile analysis all showed that the P-499 cells displayed the distinctive feature of hyperplastic growth. Further investigation confirmed that miR-499 could promote neonatal rat cardiomyocyte proliferation. MiR-499 knock-down enhanced apoptosis in the late differentiation stage in P19CL6 cells, but overexpression of miR-499 resulted in a decrease in the apoptosis rate. Sox6 was identified as a direct target of miR-499 and its expression was detected from day 8 or day 10 of cardiac differentiation of P19CL6 cells. Sox6 played a role in cell viability, inhibited cell proliferation and promoted cell apoptosis in P19CL6 cells and cardiomyocytes. The overexpression of Sox6 could reverse the proliferation and anti-apoptosis effects of miR-499. It was also found that miR-499 might exert its function by regulating cyclin D1 via its influence on Sox6.

Conclusions/Significance

miR-499 probably regulates the proliferation and apoptosis of P19CL6 cells in the late stage of cardiac differentiation via its effects on Sox6 and cyclin D1.

Effect of different suprahepatic vena cava reconstruction methods on the hemodynamics of rats after liver transplantation

Background

There are few studies on the hemodynamic changes after orthotopic liver transplantation in rats. In this study, we aimed to evaluate the effect of different suprahepatic vena cava (SHVC) reconstruction methods on the hemodynamics of rats after liver transplantation.

Materials and Methods

Three rat liver transplantation groups were created according to the SHVC reconstruction method: Kamada’s two-cuff technique, a modified veno-lined stent technique, and Harihara’s three-cuff technique. Ten rats of similar weight were grouped as the control. Anatomical, ultrasonic, and hemodynamic parameters and the microcirculation of the liver were measured after transplantation. The detailed operation time, operative complications, and animal survival were recorded.

Results

All the recipients showed portal hypertension one month after transplantation. The portal hypertension in the group with the modified veno-lined stent technique was the most severe. The value measured with real-time elastography was significantly higher in the recipients using the modified veno-lined stent technique than in the other two groups (P<0.01). There was no difference in the graft microcirculation after reperfusion among the three groups. The survival rate of the three groups displayed no difference, but the modified veno-lined stent technique led to more venous complications than the other two techniques.

Conclusions

The hemodynamics after liver transplantation in rats is determined not only by the cuff used for portal vein reconstruction but also by the cuff or stent for the SHVC. Some SHVC reconstruction methods, such as the modified veno-lined stent technique, Miyata’s or Settaf’s three-cuff techniques, significantly affect the hemodynamics.

Sources of Chemical Information, Toxicity Data and Assessment of Their Quality

This chapter identifies a range of sources that provide toxicity data that may be of use in category formation and read­across. Data in this context relate to both the chemical identity and characteristics of molecules in addition to biological (toxicological) information. Different methods of representing chemicals are given and caveats associated with the use of certain representations are also indicated. A glossary of key terms relating to assessment of data quality is provided along with guidance on methods to perform data quality assessment.

Chronic rapamycin restores brain vascular integrity and function through NO synthase activation and improves memory in symptomatic mice modeling Alzheimer's disease

Vascular pathology is a major feature of Alzheimer's disease (AD) and other dementias. We recently showed that chronic administration of the target-of-rapamycin (TOR) inhibitor rapamycin, which extends lifespan and delays aging, halts the progression of AD-like disease in transgenic human (h)APP mice modeling AD when administered before disease onset. Here we demonstrate that chronic reduction of TOR activity by rapamycin treatment started after disease onset restored cerebral blood flow (CBF) and brain vascular density, reduced cerebral amyloid angiopathy and microhemorrhages, decreased amyloid burden, and improved cognitive function in symptomatic hAPP (AD) mice. Like acetylcholine (ACh), a potent vasodilator, acute rapamycin treatment induced the phosphorylation of endothelial nitric oxide (NO) synthase (eNOS) and NO release in brain endothelium. Administration of the NOS inhibitor L-NG-Nitroarginine methyl ester reversed vasodilation as well as the protective effects of rapamycin on CBF and vasculature integrity, indicating that rapamycin preserves vascular density and CBF in AD mouse brains through NOS activation. Taken together, our data suggest that chronic reduction of TOR activity by rapamycin blocked the progression of AD-like cognitive and histopathological deficits by preserving brain vascular integrity and function. Drugs that inhibit the TOR pathway may have promise as a therapy for AD and possibly for vascular dementias.

Instruments for assessing risk of bias and other methodological criteria of published animal studies: a systematic review

BACKGROUND

Results from animal toxicology studies are critical to evaluating the potential harm from exposure to environmental chemicals or the safety of drugs prior to human testing. However, there is significant debate about how to evaluate the methodology and potential biases of the animal studies. There is no agreed-upon approach, and a systematic evaluation of current best practices is lacking.

OBJECTIVE

We performed a systematic review to identify and evaluate instruments for assessing the risk of bias and/or other methodological criteria of animal studies.

METHOD

We searched Medline (January 1966-November 2011) to identify all relevant articles. We extracted data on risk of bias criteria (e.g., randomization, blinding, allocation concealment) and other study design features included in each assessment instrument.

DISCUSSION

Thirty distinct instruments were identified, with the total number of assessed risk of bias, methodological, and/or reporting criteria ranging from 2 to 25. The most common criteria assessed were randomization (25/30, 83%), investigator blinding (23/30, 77%), and sample size calculation (18/30, 60%). In general, authors failed to empirically justify why these or other criteria were included. Nearly all (28/30, 93%) of the instruments have not been rigorously tested for validity or reliability.

CONCLUSION

Our review highlights a number of risk of bias assessment criteria that have been empirically tested for animal research, including randomization, concealment of allocation, blinding, and accounting for all animals. In addition, there is a need for empirically testing additional methodological criteria and assessing the validity and reliability of a standard risk of bias assessment instrument.

Ulinastatin attenuates oxidation, inflammation and neural apoptosis in the cerebral cortex of adult rats with ventricular fibrillation after cardiopulmonary resuscitation

OBJECTIVE

The role of Ulinastatin in neuronal injury after cardiopulmonary resuscitation has not been elucidated. We aim to evaluate the effects of Ulinastatin on inflammation, oxidation, and neuronal injury in the cerebral cortex after cardiopulmonary resuscitation.

METHODS

Ventricular fibrillation was induced in 76 adult male Wistar rats for 6 min, after which cardiopulmonary resuscitation was initiated. After spontaneous circulation returned, the rats were split into two groups: the Ulinastatin 100,000 unit/kg group or the PBS-treated control group. Blood and cerebral cortex samples were obtained and compared at 2, 4, and 8 h after return of spontaneous circulation. The protein levels of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) were assayed using an enzyme-linked immunosorbent assay, and mRNA levels were quantified via real-time polymerase chain reaction. Myeloperoxidase and Malondialdehyde were measured by spectrophotometry. The translocation of nuclear factor-κB p65 was assayed by Western blot. The viable and apoptotic neurons were detected by Nissl and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL).

RESULTS

Ulinastatin treatment decreased plasma levels of TNF-α and IL-6, expression of mRNA, and Myeloperoxidase and Malondialdehyde in the cerebral cortex. In addition, Ulinastatin attenuated the translocation of nuclear factor-κB p65 at 2, 4, and 8 hours after the return of spontaneous circulation. Ulinastatin increased the number of living neurons and decreased TUNEL-positive neuron numbers in the cortex at 72 h after the return of spontaneous circulation.

CONCLUSIONS

Ulinastatin preserved neuronal survival and inhibited neuron apoptosis after the return of spontaneous circulation in Wistar rats via attenuation of the oxidative stress response and translocation of nuclear factor-κB p65 in the cortex. In addition, Ulinastatin decreased the production of TNF-α, IL-6, Myeloperoxidase, and Malondialdehyde.

Ethical Review of Projects Involving Non-human Primates Funded under the European Union's 7th Research Framework Programme

Internet searches were performed on projects involving non-human primates (‘primates’) funded under the European Union (EU) 7th Research Framework Programme (FP7), to determine how project proposals are assessed from an ethical point of view. Due to the incompleteness of the information publicly available, the types and severity of the experiments could not be determined with certainty, although in some projects the level of harm was considered to be ‘severe’. Information was scarce regarding the numbers of primates, their sourcing, housing, care and fate, or the application of the Three Rs within projects. Project grant holders and the relevant Commission officer were consulted about their experiences with the FP7 ethics review process. Overall, it was seen as meaningful and beneficial, but some concerns were also noted. Ethical follow-up during project performance and upon completion was recognised as a valuable tool in ensuring that animal welfare requirements were adequately addressed. Based upon the outcome of the survey, recommendations are presented on how to strengthen the ethical review process under the upcoming Framework Programme ‘Horizon 2020’, while adequately taking into account the specific requirements of Directive 2010/63/EU, with the aim of limiting the harms inflicted on the animals and the numbers used, and ultimately, replacing the use of primates altogether.

Protection of the heart by treatment with a divalent-copper-selective chelator reveals a novel mechanism underlying cardiomyopathy in diabetic rats

Background

Intracellular calcium (Ca²⁺) coordinates the cardiac contraction cycle and is dysregulated in diabetic cardiomyopathy. Treatment with triethylenetetramine (TETA), a divalent-copper-selective chelator, improves cardiac structure and function in patients and rats with diabetic cardiomyopathy, but the molecular basis of this action is uncertain. Here, we used TETA to probe potential linkages between left-ventricular (LV) copper and Ca²⁺ homeostasis, and cardiac function and structure in diabetic cardiomyopathy.

Methods

We treated streptozotocin-diabetic rats with a TETA-dosage known to ameliorate LV hypertrophy in patients with diabetic cardiomyopathy. Drug treatment was begun either one (preventative protocol) or eight (restorative protocol) weeks after diabetes induction and continued thereafter for seven or eight weeks, respectively. Total copper content of the LV wall was determined, and simultaneous measurements of intracellular calcium concentrations and isometric contraction were made in LV trabeculae isolated from control, diabetic and TETA-treated diabetic rats.

Results

Total myocardial copper levels became deficient in untreated diabetes but were normalized by TETA-treatment. Cardiac contractility was markedly depressed by diabetes but TETA prevented this effect. Neither diabetes nor TETA exerted significant effects on peak or resting [Ca²⁺]_i. However, diabetic rats showed extensive cardiac remodelling and decreased myofibrillar calcium sensitivity, consistent with observed increases in phosphorylation of troponin I, whereas these changes were all prevented by TETA.

Conclusions

Diabetes causes cardiomyopathy through a copper-mediated mechanism that incorporates myocardial copper deficiency, whereas TETA treatment prevents this response and maintains the integrity of cardiac structure and myofibrillar calcium sensitivity. Altered calcium homeostasis may not be the primary defect in diabetic cardiomyopathy. Rather, a newly-described copper-mediated mechanism may cause this disease.

Gene transfer of human neuregulin-1 attenuates ventricular remodeling in diabetic cardiomyopathy rats

Neuregulin-1 (NRG-1) is a cardioactive growth factor released from endothelial cells. However, the effect of NRG-1 on ventricular remodeling in diabetic cardiomyopathy (DCM) remains unclear. The aim of the present study was to investigate the pathophysiological role of NRG-1 in a rat model of DCM. Rat cardiac microvascular endothelial cells (CMECs) were transfected with human NRG-1 (hNRG-1) lentivirus. The hNRG-1 medium was utilized to culture rat cardiomyocytes. The cardiomyocytes were counted with a hemacytometer to determine the proliferation index and Annexin V/propidium iodide double staining was employed to examine the apoptotic rate. A rat model of DCM was induced by an intraperitoneal injection of streptozotocin. The hNRG-1 lentivirus was injected into the myocardium of the DCM model rats. Four weeks after the lentiviral injection, cardiac catheterization was performed to evaluate the cardiac function. Apoptotic cells were determined by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining. Left ventricular sections were stained with Masson’s trichrome to investigate the myocardial collagen content. The expression levels of related genes and proteins were analyzed. The results indicated that hNRG-1 conditioned medium stimulated the proliferation and counteracted the apoptosis of cardiomyocytes in vitro. In the rats with DCM, gene transfer of hNRG-1 to the myocardium improved heart function, as indicated by invasive hemodynamic measurements. In addition, hNRG-1 reduced the number of apoptotic cells, decreased the expression of bax and increased the expression of bcl-2 in the myocardium of the DCM model rats. Myocardial fibrosis and type I and III pro-collagen mRNA levels in the myocardium were significantly reduced by hNRG-1. hNRG-1 also increased the expression of phospho-Akt and phospho-eNOS in the myocardium. In conclusion, the gene transfer of hNRG-1 ameliorates cardiac dysfunction in diabetes. Although further studies are required, NRG-1 appears to protect cardiomyocytes against apoptosis and to reduce the extent of myocardial interstitial fibrosis.

Infection of type I interferon receptor-deficient mice with various old world arenaviruses: a model for studying virulence and host species barriers

Lassa virus causes hemorrhagic Lassa fever in humans, while the related Old World arenaviruses Mopeia, Morogoro, and Mobala are supposedly apathogenic to humans and cause only inapparent infection in non-human primates. Here, we studied whether the virulence of Old World arenaviruses in humans and non-human primates is reflected in type I interferon receptor deficient (IFNAR^-/-) mice by testing several strains of Lassa virus vs. the apathogenic viruses Mopeia, Morogoro, and Mobala. All Lassa virus strains tested—Josiah, AV, BA366, and Nig04-10—replicated to high titers in blood, lung, kidney, heart, spleen, brain, and liver and caused disease as evidenced by weight loss and elevation of aspartate and alanine aminotransferase (AST and ALT) levels with a high AST/ALT ratio. Lassa fever-like pathology included acute hepatitis, interstitial pneumonia, and pronounced disturbance of splenic cytoarchitecture. Infiltrations of activated monocytes/macrophages expressing inducible nitric oxide synthase and T cells were found in liver and lung. In contrast, Mopeia, Morogoro, and Mobala virus replicated poorly in the animals and acute inflammatory alterations were not noted. Depletion of CD4⁺ and CD8⁺ T cells strongly enhanced susceptibility of IFNAR^-/- mice to the apathogenic viruses. In conclusion, the virulence of Old World arenaviruses in IFNAR^-/- mice correlates with their virulence in humans and non-human primates. In addition to the type I interferon system, T cells seem to regulate whether or not an arenavirus can productively infect non-host rodent species. The observation that Lassa virus overcomes the species barrier without artificial depletion of T cells suggests it is able to impair T cell functionality in a way that corresponds to depletion.

Single-molecule mRNA detection and counting in mammalian tissue

We present a protocol for visualizing and quantifying single mRNA molecules in mammalian (mouse and human) tissues. In the approach described here, sets of about 50 short oligonucleotides, each labeled with a single fluorophore, are hybridized to target mRNAs in tissue sections. Each set binds to a single mRNA molecule and can be detected by fluorescence microscopy as a diffraction-limited spot. Tissue architecture is then assessed by counterstaining the sections with DNA dye (DAPI), and cell borders can be visualized with a dye-coupled antibody. Spots are detected automatically with custom-made software, which we make freely available. The mRNA molecules thus detected are assigned to single cells within a tissue semiautomatically by using a graphical user interface developed in our laboratory. In this protocol, we describe an example of quantitative analysis of mRNA levels and localization in mouse small intestine. The procedure (from tissue dissection to obtaining data sets) takes 3 d. Data analysis will require an additional 3-7 d, depending on the type of analysis.

Animal models of human disease: challenges in enabling translation

Animal models have historically played a critical role in the exploration and characterization of disease pathophysiology, target identification, and in the in vivo evaluation of novel therapeutic agents and treatments. In the wake of numerous clinical trial failures of new chemical entities (NCEs) with promising preclinical profiles, animal models in all therapeutic areas have been increasingly criticized for their limited ability to predict NCE efficacy, safety and toxicity in humans. The present review discusses some of the challenges associated with the evaluation and predictive validation of animal models, as well as methodological flaws in both preclinical and clinical study designs that may contribute to the current translational failure rate. The testing of disease hypotheses and NCEs in multiple disease models necessitates evaluation of pharmacokinetic/pharmacodynamic (PK/PD) relationships and the earlier development of validated disease-associated biomarkers to assess target engagement and NCE efficacy. Additionally, the transparent integration of efficacy and safety data derived from animal models into the hierarchical data sets generated preclinically is essential in order to derive a level of predictive utility consistent with the degree of validation and inherent limitations of current animal models. The predictive value of an animal model is thus only as useful as the context in which it is interpreted. Finally, rather than dismissing animal models as not very useful in the drug discovery process, additional resources, like those successfully used in the preclinical PK assessment used for the selection of lead NCEs, must be focused on improving existing and developing new animal models.

Application of molecular genetics method for differentiating Martes zibellina L. heart from its adulterants in traditional Chinese medicine based on mitochondrial cytochrome b gene

The use of Martes zibellina L. heart as a famous kind of traditional Chinese medicine has been documented for many years in China. Identification of its authenticity as raw materials became a key in controlling of herbal preparations. In this study, the characteristics of mitochondrial cytochrome b (Cyt b) gene from four species of Martes were explored, and a specific molecular genetics technique for identifying the heart of M. zibellina L. in addition to some close relatives from their counterfeits was established. The bioinformatics was carried out to design the primers for the Cyt b gene based on the different species of Martes. PCR and sequencing technology were performed. The mt DNA was extracted from all of fresh M. zibellina L., Martes melampus. Martes flavigula. Martes martes heart samples and dry M. zibellina L. heart powder through the modified alkaline extracting method in addition to its counterfeits including the chicken heart, duck heart, goose heart, rabbit heart and Mustela vison. The complete mt DNA was separated from all samples used in the study, and the Cyt b gene with 310 bp segments was amplified only from M. zibellina L. heart as DNA template by the PCR technique. The sequencing indicated that the segment amplified by the PCR was homologous with the species of M. zibellina in GenBank. The data revealed that the primers and selected segment could be used as the genetic markers to identify M. zibellina L. heart from its counterfeits among different animal species.

Better reporting of scientific studies: why it matters

The PLOS Medicine Editors announce the launch of a Reporting Guidelines Collection to coincide with the Seventh International Congress on Peer Review and Biomedical Publication, to be held September 8–10, 2013, in Chicago. Please see later in the article for the Editors' Summary

Issues related to symptomatic and disease-modifying treatments affecting cognitive and neuropsychiatric comorbidities of epilepsy

Many symptoms of neurologic or psychiatric illness--such as cognitive impairment, depression, anxiety, attention deficits, and migraine--occur more frequently in people with epilepsy than in the general population. These diverse comorbidities present an underappreciated problem for people with epilepsy and their caregivers because they decrease quality of life, complicate treatment, and increase mortality. In fact, it has been suggested that comorbidities can have a greater effect on quality of life in people with epilepsy than the seizures themselves. There is increasing recognition of the frequency and impact of cognitive and behavioral comorbidities of epilepsy, highlighted in the 2012 Institute of Medicine report on epilepsy. Comorbidities have also been acknowledged, as a National Institutes of Health (NIH) Benchmark area for research in epilepsy. However, relatively little progress has been made in developing new therapies directed specifically at comorbidities. On the other hand, there have been many advances in understanding underlying mechanisms. These advances have made it possible to identify novel targets for therapy and prevention. As part of the International League Against Epilepsy/American Epilepsy Society workshop on preclinical therapy development for epilepsy, our working group considered the current state of understanding related to terminology, models, and strategies for therapy development for the comorbidities of epilepsy. Herein we summarize our findings and suggest ways to accelerate development of new therapies. We also consider important issues to improve research including those related to methodology, nonpharmacologic therapies, biomarkers, and infrastructure.

Combined antiapoptotic and antioxidant approach to acute neuroprotection for stroke in hypertensive rats

We hypothesized that targeting key points in the ischemic cascade with combined neuroglobin (Ngb) overexpression and c-jun N-terminal kinase (JNK) inhibition (SP600125) would offer greater neuroprotection than single treatment after in vitro hypoxia/reoxygenation and in a randomized, blinded in vivo experimental stroke study using a clinically relevant rat strain. Male spontaneously hypertensive stroke-prone rats underwent transient middle cerebral artery occlusion (tMCAO) and were divided into the following groups: tMCAO; tMCAO+control GFP-expressing canine adenovirus-2, CAVGFP; tMCAO+Ngb-expressing CAV-2, CAVNgb; tMCAO+SP600125; tMCAO+CAVNgb+SP600125; or sham procedure. Rats were assessed till day 14 for neurologic outcome before infarct determination. In vitro, combined lentivirus-mediated Ngb overexpression+SP600125 significantly reduced oxidative stress and apoptosis compared with single treatment(s) after hypoxia/reoxygenation in B50 cells. In vivo, infarct volume was significantly reduced by CAVNgb, SP600125, and further by CAVNgb+SP600125. The number of Ngb-positive cells in the peri-infarct cortex and striatum was significantly increased 14 days after tMCAO in animals receiving CAVNgb. Neurologic outcome, measured using a 32-point neurologic score, significantly improved with CAVNgb+SP600125 compared with single treatments at 14 days after tMCAO. Combined Ngb overexpression with JNK inhibition reduced hypoxia/reoxygenation-induced oxidative stress and apoptosis in cultured neurons and reduced infarct and improved neurologic outcome more than single therapy after in vivo experimental stroke in hypertensive rats.

Low-density lipoprotein receptor-related protein 1 (LRP1)-dependent cell signaling promotes axonal regeneration

Low-density lipoprotein receptors (LRPs) are present extensively on cells outside of the nervous system and classically exert roles in lipoprotein metabolism. It has been reported recently that LRP1 activation could phosphorylate the neurotrophin receptor TrkA in PC12 cells and increase neurite outgrowth from developing cerebellar granule cells. These intriguing findings led us to explore the hypothesis that LRP1 activation would activate canonical neurotrophic factor signaling in adult neurons and promote axonal regeneration after spinal cord injury. We now find that treatment of adult rat dorsal root ganglion neurons in vitro with LRP1 agonists (the receptor binding domain of α-2-macroglobulin or the hemopexin domain of matrix metalloproteinase 9) induces TrkC, Akt, and ERK activation; significantly increases neurite outgrowth (p < 0.01); and overcomes myelin inhibition (p < 0.05). These effects require Src family kinase activation, a classic LRP1-mediated Trk transactivator. Moreover, intrathecal infusions of LRP1 agonists significantly enhance sensory axonal sprouting and regeneration after spinal cord injury in rats compared with control-infused animals (p < 0.05). A significant role is established for lipoprotein receptors in sprouting and regeneration after CNS injury, identifying a novel class of therapeutic targets to explore for traumatic neurological disorders.

Morphological and molecular characterization of dietary-induced pseudo-albinism during post-embryonic development of Solea senegalensis (Kaup, 1858)

The appearance of the pseudo-albino phenotype was investigated in developing Senegalese sole (Solea senegalensis, Kaup 1858) larvae at morphological and molecular levels. In order to induce the development of pseudo-albinos, Senegalese sole larvae were fed Artemia enriched with high levels of arachidonic acid (ARA). The development of their skin pigmentation was compared to that of a control group fed Artemia enriched with a reference commercial product. The relative amount of skin melanophores, xanthophores and iridophores revealed that larval pigmentation developed similarly in both groups. However, results from different relative proportions, allocation patterns, shapes and sizes of skin chromatophores revealed changes in the pigmentation pattern between ARA and control groups from 33 days post hatching onwards. The new populations of chromatophores that should appear at post-metamorphosis were not formed in the ARA group. Further, spatial patterns of distribution between the already present larval xanthophores and melanophores were suggestive of short-range interaction that seemed to be implicated in the degradation of these chromatophores, leading to the appearance of the pseudo-albino phenotype. The expression profile of several key pigmentation-related genes revealed that melanophore development was promoted in pseudo-albinos without a sufficient degree of terminal differentiation, thus preventing melanogenesis. Present results suggest the potential roles of asip1 and slc24a5 genes on the down-regulation of trp1 expression, leading to defects in melanin production. Moreover, gene expression data supports the involvement of pax3, mitf and asip1 genes in the developmental disruption of the new post-metamorphic populations of melanophores, xanthophores and iridophores.