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Tuberculosis (TB) is a major public health concern worldwide; however the factors that account for resistance or susceptibility to disease are not completely understood. Although some studies suggest that the differential expression of miRNAs in peripheral blood of TB patients could be useful as biomarkers of active disease, their involvement during the inflammatory process in lungs of infected individuals is unknown. Here, we evaluated the global expression of miRNAs in the lungs of mice experimentally infected with Mycobacterium tuberculosis on 30 and 60 days post-infection. We observed that several miRNAs were differentially expressed compared to uninfected mice. Furthermore, we verified that the expression of miR-135b, miR-21, miR-155, miR-146a, and miR-146b was significantly altered in distinct leukocyte subsets isolated from lungs of infected mice, while genes potentially targeted by those miRNAs were associated with a diversity of immune related molecular pathways. Importantly, we validated the inhibition of Pellino 1 expression by miR-135b in vitro. Overall, this study contributes to the understanding of the dynamics of miRNA expression in lungs during experimental TB and adds further perspectives into the role of miRNAs on the regulation of immune processes such as leukocyte activation. (C) 2016 Elsevier Ltd. All rights reserved.

ObjectiveThe inhibition of glycolysis exerts potent antiseizure effects, as demonstrated by the efficacy of ketogenic and low-glucose/nonketogenic diets in the treatment of drug-resistant epilepsy. ATP-sensitive potassium (K-ATP) channels have been initially identified as the main determinant of the reduction of neuronal hyperexcitability. However, a plethora of other mechanisms have been proposed. Herein, we report the ability of 2-deoxy-d-glucose (2-DG), a glucose analog that inhibits glycolytic enzymes, of potentiating -aminobutyric acid (GABA)ergic tonic inhibition via neurosteroid-mediated activation of extrasynaptic GABA(A) receptors. MethodsAcute effects of 2-DG on the ATP-sensitive potassium currents, GABAergic tonic inhibition, firing activity, and interictal events were assessed in hippocampal slices by whole-cell patch-clamp and local field potential recordings of dentate gyrus granule cells. ResultsAcute application of 2-DG activates two distinct outward conductances: a K-ATP channel-mediated current and a bicuculline-sensitive tonic current. The effect of 2-DG on such GABAergic tonic currents was fully prevented by either finasteride or PK11195, which are specific inhibitors of the neurosteroidogenesis pathway acting via different mechanisms. Moreover, the oxidized form of vitamin C, dehydroascorbic acid, known for its ability to induce neurosteroidogenesis, also activated a bicuculline-sensitive tonic current in a manner indistinguishable from that of 2-DG. Finally, we found that the enhancement of K-ATP current by 2-DG primarily regulates intrinsic firing rate of granule cells, whereas the increase of the GABAergic tonic current plays a key role in reducing the frequency of interictal events evoked by treatment of hippocampal slices with the convulsive agent 4-aminopyridine. SignificanceWe demonstrated, for the first time, that 2-DG potentiates the extrasynaptic tonic GABAergic current through activation of neurosteroidogenesis. Such tonic inhibition represents the main conductance responsible for the antiseizure action of this glycolytic inhibitor.

We examine whether the frequency of amino acids across an organism's proteome is primarily determined by optimization to function or other factors, such as the structure of the genetic code. Considering all available proteins together, we first point out that the frequency of an amino acid in a proteome negatively correlates with its mass, suggesting that the genome preserves a fundamental distribution ruled by simple energetics. Given the universality of such distributions, one can use outliers, cysteine and leucine, to identify amino acids that deviate from this simple rule for functional purposes and examine those functions. We quantify the strength of such selection as the entropic cost outliers pay to defy the mass-frequency relation. Codon degeneracy of an amino acid partially explains the correlation between mass and frequency: light amino acids being typically encoded by highly degenerate codon families, with the exception of arginine. While degeneracy may be a factor in hard wiring the relationship between mass and frequency in proteomes, it does not provide a complete explanation. By examining extremophiles, we are able to show that this law weakens with temperature, likely due to protein stability considerations, thus the environment is essential. (C) 2016 Elsevier Ltd. All rights reserved.

It has been known for many years that centromeres cluster at the spindle pole body in fission yeast. In this issue of Developmental Cell, Fernandez-Alvarez et al. (2016) reveal that the functional significance of clustering is to promote spindle assembly by modulating nuclear envelope integrity at the onset of mitosis.

Programmed cell death is an essential aspect of animal development. Mutations in vertebrate genes that mediate apoptosis only mildly perturb development, suggesting that other cell death modes likely have important roles. Linker cell-type death (LCD) is a morphologically conserved cell death form operating during the development of Caenorhabditis elegans and vertebrates. We recently described a molecular network governing LCD in C. elegans, delineating a key role for the transcription factor heat-shock factor 1 (HSF-1). Although HSF-1 functions to protect cells from stress in many settings by inducing expression of protein folding chaperones, it promotes LCD by inducing expression of the conserved E2 ubiquitin-conjugating enzyme LET-70/UBE2D2, which is not induced by stress. Following whole-genome RNA interference and candidate gene screens, we identified and characterized four conserved regulators required for LCD. Here we show that two of these, NOB-1/Hox and EOR-1/PLZF, act upstream of HSF-1, in the context of Wnt signaling. A third protein, NHR-67/TLX/NR2E1, also functions upstream of HSF-1, and has a separate activity that prevents precocious expression of HSF-1 transcriptional targets. We demonstrate that the SET-16/mixed lineage leukemia 3/4 (MLL3/4) chromatin regulation complex functions at the same step or downstream of HSF-1 to control LET-70/UBE2D2 expression. Our results identify conserved proteins governing LCD, and demonstrate that transcriptional regulators influence this process at multiple levels.

Adolescent and young adult abuse of short-acting MOP-r agonists such as oxycodone is a pressing public health issue. Few preclinical studies have examined how adolescent exposure to oxycodone impacts its effects in the transition to adulthood. Objective: To determine in mice how chronic adolescent oxycodone self-administration (SA) affects subsequent oxycodone-induced conditioned place preference (CPP), locomotor activity, and antinociception once mice reach early adulthood. Methods: Adolescent C57BL/6J male mice (4 weeks old, n = 6-11) and adult mice (10 weeks old, n = 6 -10) were surgically implanted with indwelling jugular catheters. Mice then acquired oxycodone self administration (14 consecutive 2-hr daily sessions; 0.25 mg/kg/infusion) followed by a 14-day drug free (withdrawal) period in home cage. After the 14-day drug-free period, mice underwent a 10-day oxycodone CPP procedure (0, 1, 3, 10 mg/kg i.p.) or were tested for acute oxycodone-induced anti-nociception in the hot plate assay (335, 5, 7.5 mg/kg i.p.). Results: Mice that self-administered oxycodone during adolescence exhibited greater oxycodone-induced CPP (at the 3 mg/kg dose) than their yoked saline controls and mice that self-administered oxycodone during "adulthood. Oxycodone dose-dependently increased locomotor activity, but sensitization developed only to the 3 mg/kg in the mice that underwent oxycodone self-administration as adolescents. Mice that self-administered oxycodone as adolescents decreased in the anti-nociceptive effects of oxycodone in one dose (5 mg/kg), whereas animals that self-administered oxycodone as adults did not show this effect. Conclusion: Chronic adolescent oxycodone self-administration led to increased oxycodone-induced CPP (primarily 1 and 3 mg/kg, i.p.) and reduced antinociceptive effect of oxycodone (5 mg/kg, i.p.) in adulthood. (C) 2016 Elsevier Ltd. All rights reserved.

Zika virus (ZIVK) represents a new threat to global health, with particular relevance to neuroscientists, due to associated newborn and adult neurological disease. Consequences of vertical infection include microcephaly with brain and eye anomalies, and consequences of adult infection include Guillain-Barre syndrome (GBS) and meningoencephalitis. Recent data suggest specific vulnerability of neural progenitors to infection, leading to cell death and brain calcification, reminiscent of other viral syndromes. Prevailing models suggest entry into neuronal stem cells through transmembrane receptors, hijacking cellular signaling to interfere with neurogenesis and cell survival. Mechanisms of adult neurological disease are unknown, but recent evidence suggests propensity for infection of adult neural stem cells. Efforts focused on mechanisms of pathogenesis, vulnerabilities, and treatments are urgently needed.

In 2003 and 2013, the World Health Organization convened informal consultations on characterization and quality aspects of vaccines based on live virus vectors. In the resulting reports, one of several issues raised for future study was the potential for recombination of virus-vectored vaccines with wild type pathogenic virus strains. This paper presents an assessment of this issue formulated by the Brighton Collaboration. To provide an appropriate context for understanding the potential for recombination of virus-vectored vaccines, we review briefly the current status of virus-vectored vaccines, mechanisms of recombination between viruses, experience with recombination involving live attenuated vaccines in the field, and concerns raised previously in the literature regarding recombination of virus-vectored vaccines with wild type virus strains. We then present a discussion of the major variables that could influence recombination between a virus-vectored vaccine and circulating wild type virus and the consequences of such recombination, including intrinsic recombination properties of the parent virus used as a vector; sequence relatedness of vector and wild virus; virus host range, pathogenesis and transmission; replication competency of vector in target host; mechanism of vector attenuation; additional factors potentially affecting virulence; and circulation of multiple recombinant vectors in the same target population. Finally, we present some guiding principles for vector design and testing intended to anticipate and mitigate the potential for and consequences of recombination of virus-vectored vaccines with wild type pathogenic virus strains. (C) 2016 Published by Elsevier Ltd.

A previous study found that NF-kappa B activation is delayed in L929 cells infected with wild-type (wt) strains of VSV, while activation occurred earlier in cells infected with mutant strain T1026R1 (RI) that encodes a mutation in the cytotoxic matrix (M) protein. The integrity of the other R1 proteins is unknown; therefore our goal was to identify the viral component responsible for preventing NF-kappa B activation in L929 cells. We found that the M protein inhibits viral-mediated activation of NF-kappa B in the context of viral infection and when expressed alone via transfection, and that the M51R mutation in M abrogates this function. Addition of an l kappa B kinase (IKK) inhibitor blocked NF-kappa B activation and interferon-beta mRNA expression in cells infected with viruses encoding the M51R mutation in M. These results indicate that the VSV M protein inhibits activation of NF-kappa B by targeting an event upstream of IKK in the canonical pathway. (C) 2016 Elsevier Inc. All rights reserved.

Immune-mediated diseases are clinically heterogeneous but they share genetic and pathogenic mechanisms. These diseases may develop from the interplay of genetic factors and environmental or lifestyle factors. Exposure to such factors, including infectious agents, is associated with coordinated changes in gene transcription owing to epigenetic alterations. A growing understanding of how epigenetic mechanisms control gene expression patterns and cell function has been aided by the development of small-molecule inhibitors that target these processes. These chemical tools have helped to reveal the importance of epigenetics in guiding cell fate decisions during immune responses and have also highlighted the potential for targeting epigenetic mechanisms for the treatment of inflammation and immune-mediated diseases. In this Review, we discuss the most advanced areas of epigenetic drug development for autoimmune and inflammatory diseases and summarize the promising preclinical data in this exciting and evolving field. These agents will inevitably begin to move into clinical trials for use in patients with immune-mediated diseases.