Behavioral neuroendocrinology has a rich history of using diverse model organisms to elucidate general principles and evolution of hormone-brain-behavior relationships. The oxytocin and vasopressin ...systems have been studied in many species, revealing their role in regulating social behaviors. Oxytocin and vasopressin receptors show remarkable species and individual differences in distribution in the brain that have been linked to diversity in social behaviors. New technologies allow for unprecedented interrogation of the genes and neural circuitry regulating behaviors, but these approaches often require transgenic models and are most often used in mice. Here we discuss seminal findings relating the oxytocin and vasopressin systems to social behavior with a focus on non-traditional animal models. We then evaluate the potential of using CRISPR/Cas9 genome editing to examine the roles of genes and enable circuit dissection, manipulation and activity monitoring of the oxytocin and vasopressin systems. We believe that it is essential to incorporate these genetic and circuit level techniques in comparative behavioral neuroendocrinology research to ensure that our field remains innovative and attractive for the next generation of investigators and funding agencies.
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•Comparative approaches invigorate behavioral neuroendocrinology.•Important discoveries of OXT and AVP function were made in non-traditional models.•CRISPR techniques allow targeted genome editing in non-traditional models.•CRISPR allows interrogation of functional polymorphisms regulating Oxtr and Avpr1a.•CRISPR transgenics allow manipulation and monitoring of cell-type specific circuits.
Striatal circuits must be modulated for behavioral flexibility, the ability to adapt to environmental changes. Striatal astrocytes contribute to circuit neuromodulation by controlling the activity of ...ambient neurotransmitters. In particular, extracellular glutamate levels are tightly controlled by the astrocytic glutamate transporter EAAT2, influencing synaptic functioning and neural network activity. However, it remains unclear if EAAT2 responds to environmental cues to specifically shape action control.
To investigate the relationship between behavioral flexibility and experience-dependent regulation of EAAT2 expression in the dorsal striatum, mice were trained on an instrumental task. We manipulated EAAT2 expression using chemogenetic activation of astrocytic Gq signaling or in vivo morpholinos and determined the ability to adapt to novel environmental contingencies.
The loss of behavioral flexibility with task overtraining is associated with the upregulation of EAAT2, which results in enhanced glutamate clearance and altered modulation of glutamatergic neurotransmission in the lateral part of the dorsal striatum. Interfering with EAAT2 upregulation in this striatal area preserves behavioral flexibility.
Astrocytes are emerging as critical regulators of striatal functions. This work demonstrates that plasticity of EAAT2 expression in the lateral part of the dorsal striatum shapes behavior, thus providing novel mechanistic insights into how flexibility in action control is regulated.
We here describe a technique to transiently activate specific neural pathways in vivo. It comprises the combined use of a CRE-recombinase expressing canine adenovirus-2 (CAV-2) and an ...adeno-associated virus (AAV-hSyn-DIO-hM3D(Gq)-mCherry) that contains the floxed inverted sequence of the designer receptor exclusively activated by designer drugs (DREADD) hM3D(Gq)-mCherry. CAV-2 retrogradely infects projection neurons, which allowed us to specifically express hM3D(Gq)-mCherry in neurons that project from the ventral tegmental area (VTA) to the nucleus accumbens (Acb), the majority of which were dopaminergic. Activation of hM3D(Gq)-mCherry by intraperitoneal (i.p.) injections of clozapine-N-oxide (CNO) leads to increases in neuronal activity, which enabled us to specifically activate VTA to Acb projection neurons. The VTA to Acb pathway is part of the mesolimbic dopamine system and has been implicated in behavioral activation and the exertion of effort. Injections of all doses of CNO led to increases in progressive ratio (PR) performance. The effect of the lowest dose of CNO was suppressed by administration of a DRD1-antagonist, suggesting that CNO-induced increases in PR-performance are at least in part mediated by DRD1-signaling. We hereby validate the combined use of CAV-2 and DREADD-technology to activate specific neural pathways and determine consequent changes in behaviorally relevant paradigms.
When outbreaks of Highly Pathogenic Avian Influenza (HPAI) occur in OIE member countries with until then disease-free status, member countries can use 'compartmentalisation'. A compartment may be ...defined as a subset of farms under a common management system, complying with certain stringent surveillance, control and biosecurity measures, and based on that may receive a disease-free status. Based on this disease-free status the compartment is exempted from certain transport restrictions coming into force in case of outbreaks occurring in the country. For deciding whether a candidate compartment is granted official compartment status, it is relevant to assess the additional HPAI transmission risks that would arise due to the exemptions granted. These risks consist of both additional local transmission risks as well as the additional risk of a 'jump' of HPAI infection from one poultry area, via the compartment, to another area. Here such risk assessment is carried out using a spatial mathematical model for between-farm transmission in the Netherlands, yielding insight in the roles of compartment composition and contact structure and identify relevant evaluation criteria for granting HPAI compartment status. At the core of this model are transmission probabilities associated with indirect between-farm contacts, e.g. through feed delivery, egg collection and professional visitors. These probabilities were estimated from Dutch epidemic outbreak data in earlier work. The additional risk of a jump of HPAI from one area, via the compartment, to another area is calculated relative to the direct jump risk. The results show that additional transmission risks caused by a compartment to other farms are mainly dependent on the distance of densely populated poultry areas (DPPAs) to the nearest compartment farm. Apart from conditions on these distances, we also recommend specific routing requirements for transport and other movements within the compartment.
A diagnostic approach to mild bleeding disorders Boender, J.; Kruip, M. J. H. A.; Leebeek, F. W. G.
Journal of thrombosis and haemostasis,
August 2016, 2016-08-00, 20160801, Letnik:
14, Številka:
8
Journal Article
Recenzirano
Odprti dostop
Summary
Mild inherited bleeding disorders are relatively common in the general population. Despite recent advances in diagnostic approaches, mild inherited bleeding disorders still pose a significant ...diagnostic challenge. Hemorrhagic diathesis can be caused by disorders in primary hemostasis (von Willebrand disease, inherited platelet function disorders), secondary hemostasis (hemophilia A and B, other (rare) coagulant factor deficiencies) and fibrinolysis, and in connective tissue or vascular formation. This review summarizes the currently available diagnostic methods for mild bleeding disorders and their pitfalls, from structured patient history to highly specialized laboratory diagnosis. A comprehensive framework for a diagnostic approach to mild inherited bleeding disorders is proposed.
Essentials
It is unclear whether there are differences between von Willebrand factor (VWF) activity assays.
We compared the four most used VWF activity assays in 661 von Willebrand disease (VWD) ...patients.
All assays correlated excellently, but a discrepant classification was seen in 20% of patients.
Differences between VWF activity assays have a large impact on the classification of VWD.
Summary
Background
Measuring the ability of von Willebrand factor (VWF) to bind to platelets is crucial for the diagnosis and classification of von Willebrand disease (VWD). Several assays that measure this VWF activity using different principles are available, but the clinical relevance of different assay principles is unclear.
Objective
To compare the four most widely used VWF activity assays in a large VWD patient population.
Methods
We measured VWF:RCo (ristocetin to activate VWF + whole platelets), VWF:GPIbR (ristocetin + platelet glycoprotein Ib receptor GPIb fragments), VWF:GPIbM (gain‐of‐function GPIb fragments that bind VWF spontaneously without ristocetin) and VWF:Ab (monoclonal antibody directed against the GPIb binding epitope of VWF to mimic platelets) in 661 VWD patients from the nationwide ‘Willebrand in the Netherlands’ (WiN) Study.
Results
All assays correlated excellently (Pearson r > 0.9), but discrepant results led to a different classification for up to one‐fifth of VWD patients. VWF:RCo was not sensitive enough to classify 18% of patients and misclassified half of genotypic 2B VWD patients, especially those with p.Arg1306Trp. VWF:GPIbR was more sensitive, accurately classified the vast majority of patients, and was unaffected by the p.Asp1472His variant that causes artificially low VWF:RCo. VWF:GPIbM was the most precise assay but misclassified over a quarter of genotypic 2A, 2B and 3 patients. VWF:Ab, often not considered an actual VWF activity assay, performed at least equally to the other assays with regard to accurate VWD classification.
Conclusion
Although the different VWF activity assays are often considered similar, differences between assays have a large impact on the classification of VWD.
Currently available inhibitory optogenetic tools provide short and transient silencing of neurons, but they cannot provide long-lasting inhibition because of the requirement for high light ...intensities. Here we present an optimized blue-light-sensitive synthetic potassium channel, BLINK2, which showed good expression in neurons in three species. The channel is activated by illumination with low doses of blue light, and in our experiments it remained active over (tens of) minutes in the dark after the illumination was stopped. This activation caused long periods of inhibition of neuronal firing in ex vivo recordings of mouse neurons and impaired motor neuron response in zebrafish in vivo. As a proof-of-concept application, we demonstrated that in a freely moving rat model of neuropathic pain, the activation of a small number of BLINK2 channels caused a long-lasting (>30 min) reduction in pain sensation.
Obesity is a risk factor for type II diabetes, atherosclerosis, and some forms of cancer. Variation in common measures of obesity (e.g., BMI, waist/hip ratio) is largely explained by heritability. ...The advent of genome‐wide association studies (GWAS) has made it possible to identify several genetic variants that associate with measures of obesity, but how exactly these genetic variants contribute to overweight has remained largely unresolved. One first hint is given by the fact that many of the associated variants reside in or near genes that act in the central nervous system, which implicates neuronal signaling in the etiology of obesity. Although the brain controls both energy intake and expenditure, it has more capacity to regulate energy intake rather than energy expenditure. In environments where food is abundant, this renders the body prone to weight increases. To gain more insight into the neurobiological mechanisms involved, we set out to investigate the effect of dietary exposure on the expression levels of obesity‐associated genes in the ventro‐medial hypothalamus (VMH)/arcuate nucleus (ARC) and the substantia nigra (SN)/ventral tegmental area (VTA), two brain regions that are implicated in feeding behavior. We show that the expression of Etv5, Faim2, Fto, Negr1 but not Sh2b1 is affected by nutritional state in these two areas, thereby providing insight into the relationship between nutritional state and expression levels of obesity‐associated genes in two brain areas relevant to feeding.
Abstract Geographical maps indicating the value of the basic reproduction number, R0 , can be used to identify areas of higher risk for an outbreak after an introduction. We develop a methodology to ...create R0 maps for vector-borne diseases, using bluetongue virus as a case study. This method provides a tool for gauging the extent of environmental effects on disease emergence. The method involves integrating vector-abundance data with statistical approaches to predict abundance from satellite imagery and with the biologically mechanistic modelling that underlies R0 . We illustrate the method with three applications for bluetongue virus in the Netherlands: 1) a simple R0 map for the situation in September 2006, 2) species-specific R0 maps based on satellite-data derived predictions, and 3) monthly R0 maps throughout the year. These applications ought to be considered as a proof-of-principle and illustrations of the methods described, rather than as ready-to-use risk maps. Altogether, this is a first step towards an integrative method to predict risk of establishment of diseases based on mathematical modelling combined with a geographic information system that may comprise climatic variables, landscape features, land use, and other relevant factors determining the risk of establishment for bluetongue as well as of other emerging vector-borne diseases.
The striatum harbors two neuronal populations that enable action selection. One population represents the striatonigral pathway, expresses the dopamine receptor D1 (DRD1) and promotes the execution ...of motor programs, while the other population represents the striatopallidal pathway, expresses the dopamine receptor D2 (DRD2) and suppresses voluntary activity. The two populations integrate distinct sensorimotor, cognitive, and emotional information streams and their combined activity enables the selection of adaptive behaviors. Characterization of these populations is critical to the understanding of their role in action selection, because it aids the identification of the molecular mechanisms that separate them. To that end, we used fluorescent in situ hybridization to quantify the percentage of striatal cells that (co)express dopaminergic receptors and receptors of the cannabinoid, melanocortin or opioid neurotransmitters systems. Our main findings are that the cannabinoid 1 receptor is equally expressed on both populations with a gradient from dorsal to ventral striatum, that the opioid receptors have a preference for expression with either the DRD1 or DRD2 and that the melanocortin 4 receptor (MC4R) is predominantly expressed in ventral parts of the striatum. In addition, we find that the level of MC4R expression determines its localization to either the DRD1 or the DRD2 population. Thereby, we provide insight into the sensitivity of the two dopaminoceptive populations to these neurotransmitters and progress the understanding of the mechanisms that enable action selection.
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