30 research outputs found

    MicroRNAs Are Involved in the Development of Morphine-Induced Analgesic Tolerance and Regulate Functionally Relevant Changes in Serpini1.

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    Long-term opioid treatment results in reduced therapeutic efficacy and in turn leads to an increase in the dose required to produce equivalent pain relief and alleviate break-through or insurmountable pain. Altered gene expression is a likely means for inducing long-term neuroadaptations responsible for tolerance. Studies conducted by our laboratory (Tapocik et al., 2009) revealed a network of gene expression changes occurring in canonical pathways involved in neuroplasticity, and uncovered miRNA processing as a potential mechanism. In particular, the mRNA coding the protein responsible for processing miRNAs, Dicer1, was positively correlated with the development of analgesic tolerance. The purpose of the present study was to test the hypothesis that miRNAs play a significant role in the development of analgesic tolerance as measured by thermal nociception. Dicer1 knockdown, miRNA profiling, bioinformatics, and confirmation of high value targets were used to test the proposition. Regionally targeted Dicer1 knockdown (via shRNA) had the anticipated consequence of eliminating the development of tolerance in C57BL/6J (B6) mice, thus supporting the involvement of miRNAs in the development of tolerance. MiRNA expression profiling identified a core set of chronic morphine-regulated miRNAs (miR\u27s 27a, 9, 483, 505, 146b, 202). Bioinformatics approaches were implemented to identify and prioritize their predicted target mRNAs. We focused our attention on miR27a and its predicted target serpin peptidase inhibitor clade I (Serpini1) mRNA, a transcript known to be intricately involved in dendritic spine density regulation in a manner consistent with chronic morphine\u27s consequences and previously found to be correlated with the development of analgesic tolerance. In vitro reporter assay confirmed the targeting of the Serpini1 3′-untranslated region by miR27a. Interestingly miR27a was found to positively regulateSerpini1 mRNA and protein levels in multiple neuronal cell lines. Lastly, Serpini1 knockout mice developed analgesic tolerance at a slower rate than wild-type mice thus confirming a role for the protein in analgesic tolerance. Overall, these results provide evidence to support a specific role for miR27a and Serpini1 in the behavioral response to chronic opioid administration (COA) and suggest that miRNA expression and mRNA targeting may underlie the neuroadaptations that mediate tolerance to the analgesic effects of morphine

    Physical Activity Across the Curriculum (PAAC): a randomized controlled trial to promote physical activity and diminish overweight and obesity in elementary school children

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    Objective Physical Activity Across the Curriculum (PAAC) was a three-year cluster randomized controlled trial to promote physical activity and diminish increases in overweight and obesity in elementary school children. Methods Twenty-four elementary schools were cluster randomized to the PAAC intervention or served as control. All children in grades two and three were followed to grades four and five. PAAC promoted 90 minutes/wk of moderate to vigorous intensity physically active academic lessons delivered by classroom teachers. BMI was the primary outcome, daily PA and academic achievement were secondary outcomes. Results The three-year change in BMI for PAAC was 2.0 ± 1.9 and control 1.9 ± 1.9, respectively (NS). However, change in BMI from baseline to three years was significantly influenced by exposure to PAAC. Schools with ≥75 minutes of PAAC/wk showed significantly less increase in BMI at three years compared to schools that had <75 minutes of PAAC (1.8 ± 1.8 vs. 2.4 ± 2.0, p=0.02). PAAC schools had significantly greater changes in daily PA and academic achievement scores. Conclusions The PAAC approach may promote daily PA and academic achievement in elementary school children. Additionally, 75 minutes of PAAC activities may attenuate increases in BMI

    Weight management for individuals with intellectual and developmental disabilities: Rationale and design for an 18 month randomized trial

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    Weight management for individuals with intellectual and developmental disabilities (IDD) has received limited attention. Studies on weight management in this population have been conducted over short time frames, in small samples with inadequate statistical power, infrequently used a randomized design, and have not evaluated the use of emerging effective dietary strategies such as pre-packaged meals (PMs). Low energy/fat PMs may be useful in individuals with IDD as they simplify meal planning, limit undesirable food choices, teach appropriate portion sizes, are convenient and easy to prepare, and when combined with fruits and vegetables provide a high volume, low energy dense meal. A randomized effectiveness trial will be conducted in 150 overweight/obese adults with mild to moderate IDD, and their study partners to compare weight loss (6 months) and weight maintenance (12 months) between 2 weight management approaches: 1. A Stop Light Diet enhanced with reduced energy/fat PMs (eSLD); and 2. A recommended care reduced energy/fat meal plan diet (RC). The primary aim is to compare weight loss (0–6 months) and weight maintenance (7–18 months) between the eSLD and RC diets. Secondarily, changes in chronic disease risk factors between the eSLD and RC diets including blood pressure, glucose, insulin, LDL-cholesterol, and HDL-cholesterol will be compared during both weight loss and weight maintenance. Finally, potential mediators of weight loss including energy intake, physical activity, data recording, adherence to the diet, study partner self-efficacy and daily stress related to dietary change will be explored

    Physical activity across the curriculum: year one process evaluation results

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    <p>Abstract</p> <p>Background</p> <p>Physical Activity Across the Curriculum (PAAC) is a 3-year elementary school-based intervention to determine if increased amounts of moderate intensity physical activity performed in the classroom will diminish gains in body mass index (BMI). It is a cluster-randomized, controlled trial, involving 4905 children (2505 intervention, 2400 control).</p> <p>Methods</p> <p>We collected both qualitative and quantitative process evaluation data from 24 schools (14 intervention and 10 control), which included tracking teacher training issues, challenges and barriers to effective implementation of PAAC lessons, initial and continual use of program specified activities, and potential competing factors, which might contaminate or lessen program effects.</p> <p>Results</p> <p>Overall teacher attendance at training sessions showed exceptional reach. Teachers incorporated active lessons on most days, resulting in significantly greater student physical activity levels compared to controls (p < 0.0001). Enjoyment ratings for classroom-based lessons were also higher for intervention students. Competing factors, which might influence program results, were not carried out at intervention or control schools or were judged to be minimal.</p> <p>Conclusion</p> <p>In the first year of the PAAC intervention, process evaluation results were instrumental in identifying successes and challenges faced by teachers when trying to modify existing academic lessons to incorporate physical activity.</p

    Physical activity and academic achievement across the curriculum (A + PAAC): rationale and design of a 3-year, cluster-randomized trial

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    Abstract Background Improving academic achievement and reducing the rates of obesity in elementary school students are both of considerable interest. Increased physical activity during academic instruction time during school offers a potential intervention to address both issues. A program titled &#8220;Physical Activity Across the Curriculum&#8221; (PAAC) was developed in which classroom teachers in 22 elementary schools were trained to deliver academic instruction using physical activity with a primary aim of preventing increased BMI. A secondary analysis of data assessed the impact of PAAC on academic achievement using the Weschler Individual Achievement Test-II and significant improvements were shown for reading, math and spelling in students who participated in PAAC. Based on the results from PAAC, an adequately powered trial will be conducted to assess differences in academic achievement between intervention and control schools called, &#8220;Academic Achievement and Physical Activity Across the Curriculum (A&#8201;+&#8201;PAAC).&#8221; Methods/design Seventeen elementary schools were cluster randomized to A&#8201;+&#8201;PAAC or control for a 3-year trial. Classroom teachers were trained to deliver academic instruction through moderate-to-vigorous physical activity with a target of 100+ minutes of A&#8201;+&#8201;PAAC activities per week. The primary outcome measure is academic achievement measured by the Weschler Individual Achievement Test-III, which was administered at baseline (Fall 2011) and will be repeated in the spring of each year by assessors blinded to condition. Potential mediators of any association between A&#8201;+&#8201;PAAC and academic achievement will be examined on the same schedule and include changes in cognitive function, cardiovascular fitness, daily physical activity, BMI, and attention-to-task. An extensive process analysis will be conducted to document the fidelity of the intervention. School and student recruitment/randomization, teacher training, and baseline testing for A&#8201;+&#8201;PAAC have been completed. Nine schools were randomized to the intervention and 8 to control. A random sample of students in each school, stratified by gender and grade (A&#8201;+&#8201;PAAC&#8201;=&#8201;370, Control&#8201;=&#8201;317), was selected for outcome assessments from those who provided parental consent/child assent. Baseline data by intervention group are presented. Discussion If successful, the A&#8201;+&#8201;PAAC approach could be easily and inexpensively scaled and disseminated across elementary schools to improve both educational quality and health. Funding source: R01- DK85317. Trial registration: US NIH Clinical Trials, http://NCT01699295.Peer Reviewe

    NMDAR inhibition-independent antidepressant actions of ketamine metabolites

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    Major depressive disorder afflicts ~16 percent of the world population at some point in their lives. Despite a number of available monoaminergic-based antidepressants, most patients require many weeks, if not months, to respond to these treatments, and many patients never attain sustained remission of their symptoms. The non-competitive glutamatergic N-methyl-D-aspartate receptor (NMDAR) antagonist, (R,S)-ketamine (ketamine), exerts rapid and sustained antidepressant effects following a single dose in depressed patients. Here we show that the metabolism of ketamine to (2S,6S;2R,6R)-hydroxynorketamine (HNK) is essential for its antidepressant effects, and that the (2R,6R)-HNK enantiomer exerts behavioural, electroencephalographic, electrophysiological and cellular antidepressant actions in vivo. Notably, we demonstrate that these antidepressant actions are NMDAR inhibition-independent but they involve early and sustained α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor activation. We also establish that (2R,6R)-HNK lacks ketamine-related side-effects. Our results indicate a novel mechanism underlying ketamine’s unique antidepressant properties, which involves the required activity of a distinct metabolite and is independent of NMDAR inhibition. These findings have relevance for the development of next generation, rapid-acting antidepressants

    Neuroplasticity, axonal guidance and micro-RNA genes are associated with morphine self-administration behavior

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    Neuroadaptations in the ventral striatum (VS) and ventral midbrain (VMB) following chronic opioid administration are thought to contribute to the pathogenesis and persistence of opiate addiction. In order to identify candidate genes involved in these neuroadaptations, we utilized a behavior-genetics strategy designed to associate contingent intravenous drug self-administration with specific patterns of gene expression in inbred mice differentially predisposed to the rewarding effects of morphine. In a Yoked-control paradigm, C57BL/6J mice showed clear morphine-reinforced behavior, whereas DBA/2J mice did not. Moreover, the Yoked-control paradigm revealed the powerful consequences of self-administration versus passive administration at the level of gene expression. Morphine self-administration in the C57BL/6J mice uniquely up- or down-regulated 237 genes in the VS and 131 genes in the VMB. Interestingly, only a handful of the C57BL/6J self-administration genes (\u3c3%) exhibited a similar expression pattern in the DBA/2J mice. Hence, specific sets of genes could be confidently assigned to regional effects of morphine in a contingent- and genotype-dependent manner. Bioinformatics analysis revealed that neuroplasticity, axonal guidance and micro-RNAs (miRNAs) were among the key themes associated with drug self-administration. Noteworthy were the primary miRNA genes H19 and micro-RNA containing gene (Mirg), processed, respectively, to mature miRNAs miR-675 and miR-154, because they are prime candidates to mediate network-like changes in responses to chronic drug administration. These miRNAs have postulated roles in dopaminergic neuron differentiation and mu-opioid receptor regulation. The strategic approach designed to focus on reinforcement-associated genes provides new insight into the role of neuroplasticity pathways and miRNAs in drug addiction. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction

    Neuroplasticity, axonal guidance and micro-RNA genes are associated with morphine self-administration behavior

    No full text
    Neuroadaptations in the ventral striatum (VS) and ventral midbrain (VMB) following chronic opioid administration are thought to contribute to the pathogenesis and persistence of opiate addiction. In order to identify candidate genes involved in these neuroadaptations, we utilized a behavior-genetics strategy designed to associate contingent intravenous drug self-administration with specific patterns of gene expression in inbred mice differentially predisposed to the rewarding effects of morphine. In a Yoked-control paradigm, C57BL/6J mice showed clear morphine-reinforced behavior, whereas DBA/2J mice did not. Moreover, the Yoked-control paradigm revealed the powerful consequences of self-administration versus passive administration at the level of gene expression. Morphine self-administration in the C57BL/6J mice uniquely up- or down-regulated 237 genes in the VS and 131 genes in the VMB. Interestingly, only a handful of the C57BL/6J self-administration genes (\u3c3%) exhibited a similar expression pattern in the DBA/2J mice. Hence, specific sets of genes could be confidently assigned to regional effects of morphine in a contingent- and genotype-dependent manner. Bioinformatics analysis revealed that neuroplasticity, axonal guidance and micro-RNAs (miRNAs) were among the key themes associated with drug self-administration. Noteworthy were the primary miRNA genes H19 and micro-RNA containing gene (Mirg), processed, respectively, to mature miRNAs miR-675 and miR-154, because they are prime candidates to mediate network-like changes in responses to chronic drug administration. These miRNAs have postulated roles in dopaminergic neuron differentiation and mu-opioid receptor regulation. The strategic approach designed to focus on reinforcement-associated genes provides new insight into the role of neuroplasticity pathways and miRNAs in drug addiction. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction

    Identification of candidate genes and gene networks specifically associated with analgesic tolerance to morphine

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    Chronic morphine administration may alter the expression of hundreds to thousands of genes. However, only a subset of these genes is likely involved in analgesic tolerance. In this report, we used a behavior genetics strategy to identify candidate genes specifically linked to the development of morphine tolerance. Two inbred genotypes [C57BL/6J (B6), DBA2/J (D2)] and two reciprocal congenic genotypes (B6D2, D2B6) with the proximal region of chromosome 10 (Chr10) introgressed into opposing backgrounds served as the behavior genetic filter. Tolerance after therapeutically relevant doses of morphine developed most rapidly in the B6 followed by the B6D2 genotype and did not develop in the D2 mice and only slightly in the D2B6 animals indicating a strong influence of the proximal region of Chrl0 in the development of tolerance. Gene expression profiling and pattern matching identified 64,53,86, and 123 predisposition genes and 81, 96,106, and 82 tolerance genes in the periaqueductal gray (PAG), prefrontal cortex, temporal lobe, and ventral striatum, respectively. A potential gene network was identified in the PAG in which 19 of the 34 genes were strongly associated with tolerance. Eleven of the network genes were found to reside in quantitative trait loci previously associated with morphine-related behaviors, whereas seven were predictive of tolerance (morphine-naive condition). Overall, the genes modified by chronic morphine administration show a strong presence in canonical pathways representative of neuroadaptation. A potentially significant role for the micro-RNA and epigenetic mechanisms in response to chronic administration of pharmacologically relevant doses of morphine was highlighted by candidate genes Dicer and H19. Copyright © 2009 Society for Neuroscience
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