Asymmetric dimethylarginine induces maladaptive function of the blood-brain barrier.

Growing body of evidence suggests that cardiovascular risk factor, asymmetric dimethylarginine (ADMA), can be implicated in the pathogenesis of neurodegenerative and psychiatric disorders. In part, ADMA can affect brain health negatively modulating critical functions of the blood-brain barrier (BBB). The precise mechanisms and consequences of ADMA action on the cerebral vasculature remains unexplored.

The effects of nickel chloride on papillary muscle contractility under normothermic and hypothermic conditions: Comparison of active and hibernating ground squirrels (Urocitellus undulatus) with Wistar rats.

Extracellular Ca plays a pivotal role in the regulation of cardiac contractility under normal and extreme conditions. Here, by using nickel chloride (NiCl), a non-specific blocker of extracellular Ca influx, we studied the input of extracellular Ca on the regulation of papillary muscle (PM) contractility under normal and hypothermic conditions in ground squirrels (GS), and rats. By measuring isometric force of contraction, we studied how NiCl affects force-frequency relationship and the rest effect in PM of these species at 30 °C and 10 °C.

Sex differences in pre- and post-synaptic glutamate signaling in the nucleus accumbens core.

Background: Glutamate signaling within the nucleus accumbens underlies motivated behavior and is involved in psychiatric disease. Although behavioral sex differences in these processes are well-established, the neural mechanisms driving these differences are largely unexplored. In these studies, we examine potential sex differences in synaptic plasticity and excitatory transmission within the nucleus accumbens core.

Retromer Stabilization Improves Cognitive Function and Synaptic Plasticity in a Mouse Model of Down Syndrome.

Background: Retromer complex proteins are decreased in postmortem brain tissues from Down syndrome subjects and inversely correlate with the Alzheimer's disease-like neuropathology. However, whether targeting in vivo the retromer system affects cognitive deficits and synaptic function in Down syndrome remains unknown.

Objective: The aim of the current study was to examine the effects of pharmacological retromer stabilization on cognitive and synaptic functions in a mouse model of Down syndrome.

Regulation of Papillary Muscle Contractility by NAD and Ammonia Interplay: Contribution of Ion Channels and Exchangers.

Various models, including stem cells derived and isolated cardiomyocytes with overexpressed channels, are utilized to analyze the functional interplay of diverse ion currents involved in cardiac automaticity and excitation-contraction coupling control. Here, we used β-NAD and ammonia, known hyperpolarizing and depolarizing agents, respectively, and applied inhibitory analysis to reveal the interplay of several ion channels implicated in rat papillary muscle contractility control. We demonstrated that: 4 mM β-NAD, having no strong impact on resting membrane potential (RMP) and action potential duration (APD90) of ventricular cardiomyocytes, evoked significant suppression of isometric force (F) of paced papillary muscle.

Anti-hypoxic effect of interleukin-10 in hippocampal neurons is mediated by modulation of TASK-1 and TASK-3 channels activity.

It has been shown that anti-inflammatory cytokine interleukin-10 (IL-10) can exert anti-hypoxic effect preventing post-hypoxic neuronal hyperexcitability. Yet, exact mechanisms of IL-10 mediated anti-hypoxic action on neuronal function are not fully understood. We suggested that IL-10 can exert its anti-hypoxic action via modulation of activity of two-pore potassium TASK-1 and TASK-3 channels.

Effects of Cardiotoxins from Cobra Venom on Rat Heart Muscle and Aorta: A Comparative Study of Toxin-Induced Contraction Mechanisms.

Cardiotoxins (CaTxs) are a group of snake toxins that affect the cardiovascular system (CVS). Two types (S and P) of CaTxs are known, but the exact differences in the effects of these types on CVS have not been thoroughly studied. We investigated cellular mechanisms of action on CVS for cobra CaTxs CTX-1 (S-type) and CTX-2 (P-type) focusing on the papillary muscle (PM) contractility and contraction of aortic rings (AR) supplemented by pharmacological analysis.

Inhibition of the Akt/PKB Kinase Increases Na1.6-Mediated Currents and Neuronal Excitability in CA1 Hippocampal Pyramidal Neurons.

In neurons, changes in Akt activity have been detected in response to the stimulation of transmembrane receptors. However, the mechanisms that lead to changes in neuronal function upon Akt inhibition are still poorly understood. In the present study, we interrogate how Akt inhibition could affect the activity of the neuronal Na channels with while impacting intrinsic excitability.

α1-Adrenergic receptor regulates papillary muscle and aortic segment contractile function via modulation of store-operated Ca entry in long-tailed ground squirrels Urocitellus undulatus.

The effect of phenylephrine (PE) on right ventricle papillary muscle (PM) and aortic segment (AS) contractile activity was studied in long-tailed ground squirrels Urocitellus undulatus during summer activity, torpor and interbout active (IBA) periods in comparison to rat. We found that PE (10 μM) exerts positive inotropic effect on ground squirrel PM that was blocked by α1-AR inhibitor-prazosin. PE differently affected frequency dependence of PM contraction in ground squirrels and rats.

Inhibition of AKT Signaling Alters βIV Spectrin Distribution at the AIS and Increases Neuronal Excitability.

The axon initial segment (AIS) is a highly regulated subcellular domain required for neuronal firing. Changes in the AIS protein composition and distribution are a form of structural plasticity, which powerfully regulates neuronal activity and may underlie several neuropsychiatric and neurodegenerative disorders. Despite its physiological and pathophysiological relevance, the signaling pathways mediating AIS protein distribution are still poorly studied.

Involvement of NMDA and GABA(A) receptors in modulation of spontaneous activity in hippocampal culture: Interrelations between burst firing and intracellular calcium signal.

Spontaneous burst firing is a hallmark attributed to the neuronal network activity. It is known to be accompanied by intracellular calcium [Са] oscillations within the bursting neurons. Studying mechanisms underlying regulation of burst firing is highly relevant, since impairment in neuronal bursting accompanies different neurological disorders.

Can DNA barcoding be used to identify closely related Clunio Haliday, 1855 species (Diptera: Chironomidae, Orthocladiinae)?

DNA barcoding based on a fragment of mitochondrial Cytochrome C Oxidase subunit 1 gene (COI) was applied to the two chironomids Clunio balticus Heimbach (690 base pairs) and C. ponticus Michailova (691 base pairs). The two species differed by one deletion in the nucleotide sequence Adenine.

Mathematical Modelling in Biomedicine: A Primer for the Curious and the Skeptic.

In most disciplines of natural sciences and engineering, mathematical and computational modelling are mainstay methods which are usefulness beyond doubt. These disciplines would not have reached today's level of sophistication without an intensive use of mathematical and computational models together with quantitative data. This approach has not been followed in much of molecular biology and biomedicine, however, where qualitative descriptions are accepted as a satisfactory replacement for mathematical rigor and the use of computational models is seen by many as a fringe practice rather than as a powerful scientific method.

Dissecting Cellular Mechanisms of Long-Chain Acylcarnitines-Driven Cardiotoxicity: Disturbance of Calcium Homeostasis, Activation of Ca-Dependent Phospholipases, and Mitochondrial Energetics Collapse.

Long-chain acylcarnitines (LCAC) are implicated in ischemia-reperfusion (I/R)-induced myocardial injury and mitochondrial dysfunction. Yet, molecular mechanisms underlying involvement of LCAC in cardiac injury are not sufficiently studied. It is known that in cardiomyocytes, palmitoylcarnitine (PC) can induce cytosolic Ca accumulation, implicating L-type calcium channels, Na/Ca exchanger, and Ca-release from sarcoplasmic reticulum (SR).

The role of cooperativity in a p53-miR34 dynamical mathematical model.

The objective of this study is to evaluate the role of cooperativity, captured by the Hill coefficient, in a minimal mathematical model describing the interactions between p53 and miR-34a. The model equations are analyzed for negative, none and normal cooperativity using a specific version of bifurcation theory and they are solved numerically. Special attention is paid to the sign of so-called first Lyapunov value.

Extra virgin olive oil improves synaptic activity, short-term plasticity, memory, and neuropathology in a tauopathy model.

In recent years, increasing evidence has accumulated supporting the health benefits of extra virgin olive oil (EVOO). Previous studies showed that EVOO supplementation improves Alzheimer's disease (AD)-like amyloidotic phenotype of transgenic mice. However, while much attention has been focused on EVOO-mediated modulation of Aβ processing, its direct influence on tau metabolism in vivo and synaptic function is still poorly characterized.

Interleukin-10 and transforming growth factor-β1 facilitate long-term potentiation in CA1 region of hippocampus.

It has been shown that pro-inflammatory cytokines preferentially attenuate long-term potentiation (LTP), at the same time the effect of anti-inflammatory cytokines on synaptic plasticity has not been fully studied yet. Here we studied the effect of two anti-inflammatory cytokines - interleukin-10 (IL-10) and transforming growth factor-β1 (TGF-β1) on long-term potentiation. It was found that exogenously added IL-10 as well as TGF-β1 were able to effectively facilitate LTP evoked with ether high frequency or theta burst stimulation protocols in CA1 area of hippocampus.

Interleukin-10 Facilitates Glutamatergic Synaptic Transmission and Homeostatic Plasticity in Cultured Hippocampal Neurons.

Anti-inflammatory cytokines are known to exert neuroprotective action ameliorating aberrant neuronal network activity associated with inflammatory responses. Yet, it is still not fully understood if anti-inflammatory cytokines play a significant role in the regulation of synaptic activity under normal conditions. Thus, the aim of our study was to investigate the effect of Interleukin-10 (IL-10) on neuronal synaptic transmission and plasticity.

Environmental Enrichment and Social Isolation Mediate Neuroplasticity of Medium Spiny Neurons through the GSK3 Pathway.

Resilience and vulnerability to neuropsychiatric disorders are linked to molecular changes underlying excitability that are still poorly understood. Here, we identify glycogen-synthase kinase 3β (GSK3β) and voltage-gated Na channel Nav1.6 as regulators of neuroplasticity induced by environmentally enriched (EC) or isolated (IC) conditions-models for resilience and vulnerability.

Functional Modulation of Voltage-Gated Sodium Channels by a FGF14-Based Peptidomimetic.

Protein-protein interactions (PPI) offer unexploited opportunities for CNS drug discovery and neurochemical probe development. Here, we present ZL181, a novel peptidomimetic targeting the PPI interface of the voltage-gated Na channel Nav1.6 and its regulatory protein fibroblast growth factor 14 (FGF14).

Interleukin-10 and PD150606 modulate expression of AMPA receptor GluA1 and GluA2 subunits under hypoxic conditions.

The goal of this study was to evaluate the effects of anti-inflammatory cytokine, interleukin-10 (IL-10), and calpain inhibitor, PD150606, on the expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits in rat hippocampal slices exposed to repeated brief hypoxic episodes. We studied both individual and combinatory effects of PD150606 and IL-10 on the expression of AMPA receptor subunits under hypoxic conditions for GluA1 and GluA2 as well as their phosphorylated forms - pSer831-GluA1 and pSer880-GluA2. Additionally, we studied whether brief hypoxic episodes and IL-10 may affect mRNA expression of transcriptional factors such as hypoxia-inducible factor-1α and nuclear factor κB (NF-κB).

PPARgamma agonists rescue increased phosphorylation of FGF14 at S226 in the Tg2576 mouse model of Alzheimer's disease.

Background: Cognitive impairment in humans with Alzheimer's disease (AD) and in animal models of Aβ-pathology can be ameliorated by treatments with the nuclear receptor peroxisome proliferator-activated receptor-gamma (PPARγ) agonists, such as rosiglitazone (RSG). Previously, we demonstrated that in the Tg2576 animal model of AD, RSG treatment rescued cognitive deficits and reduced aberrant activity of granule neurons in the dentate gyrus (DG), an area critical for memory formation.

Methods: We used a combination of mass spectrometry, confocal imaging, electrophysiology and split-luciferase assay and in vitro phosphorylation and Ingenuity Pathway Analysis.

Glycogen synthase kinase 3 beta alters anxiety-, depression-, and addiction-related behaviors and neuronal activity in the nucleus accumbens shell.

Psychiatric disorders such as anxiety, depression and addiction are often comorbid brain pathologies thought to share common mechanistic biology. As part of the cortico-limbic circuit, the nucleus accumbens shell (NAcSh) plays a fundamental role in integrating information in the circuit, such that modulation of NAcSh circuitry alters anxiety, depression, and addiction-related behaviors. Intracellular kinase cascades in the NAcSh have proven important mediators of behavior.

Consequences of acute Na1.1 exposure to deltamethrin.

Background: Pyrethroid insecticides are the most popular class of insecticides in the world, despite their near-ubiquity, their effects of delaying the onset of inactivation of voltage-gated sodium (Na) channels have not been well-evaluated in all the mammalian Na isoforms.

Objective: Here we compare the well-studied Na1.6 isoforms to the less-understood Na1.