Alcohol consumption is known to lead to gene expression changes in the brain. After performing weighted gene co-expression network analyses (WGCNA) on genome-wide mRNA and microRNA (miRNA) expression in Nucleus Accumbens (NAc) of subjects with alcohol dependence (AD; N = 18) and of matched controls (N = 18), six mRNA and three miRNA modules significantly correlated with AD were identified (Bonferoni-adj. p≤ 0.05). Cell-type-specific transcriptome analyses revealed two of the mRNA modules to be enriched for neuronal specific marker genes and downregulated in AD, whereas the remaining four mRNA modules were enriched for astrocyte and microglial specific marker genes and upregulated in AD. Gene set enrichment analysis demonstrated that neuronal specific modules were enriched for genes involved in oxidative phosphorylation, mitochondrial dysfunction and MAPK signaling. Glial-specific modules were predominantly enriched for genes involved in processes related to immune functions, i.e. cytokine signaling (all adj. p≤ 0.05). In mRNA and miRNA modules, 461 and 25 candidate hub genes were identified, respectively. In contrast to the expected biological functions of miRNAs, correlation analyses between mRNA and miRNA hub genes revealed a higher number of positive than negative correlations (χ2 test p≤ 0.0001). Integration of hub gene expression with genome-wide genotypic data resulted in 591 mRNA cis-eQTLs and 62 miRNA cis-eQTLs. mRNA cis-eQTLs were significantly enriched for AD diagnosis and AD symptom counts (adj. p = 0.014 and p = 0.024, respectively) in AD GWAS signals in a large, independent genetic sample from the Collaborative Study on Genetics of Alcohol (COGA). In conclusion, our study identified putative gene network hubs coordinating mRNA and miRNA co-expression changes in the NAc of AD subjects, and our genetic (cis-eQTL) analysis provides novel insights into the etiological mechanisms of AD.
Rationale Vascular endothelial growth factor (VEGF)-B selectively binds VEGF receptor (VEGFR)-1, a receptor that does not mediate angiogenesis, and is emerging as a major cytoprotective factor. Objective To test the hypothesis that VEGF-B exerts non–angiogenesis-related cardioprotective effects in nonischemic dilated cardiomyopathy. Methods and Results AAV-9–carried VEGF-B167 cDNA (1012 genome copies) was injected into the myocardium of chronically instrumented dogs developing tachypacing-induced dilated cardiomyopathy. After 4 weeks of pacing, green fluorescent protein–transduced dogs (AAV-control, n=8) were in overt congestive heart failure, whereas the VEGF-B–transduced (AAV-VEGF-B, n=8) were still in a well-compensated state, with physiological arterial PO2. Left ventricular (LV) end-diastolic pressure in AAV-VEGF-B and AAV-control was, respectively, 15.0±1.5 versus 26.7±1.8 mm Hg and LV regional fractional shortening was 9.4±1.6% versus 3.0±0.6% (all P<0.05). VEGF-B prevented LV wall thinning but did not induce cardiac hypertrophy and did not affect the density of α-smooth muscle actin–positive microvessels, whereas it normalized TUNEL-positive cardiomyocytes and caspase-9 and -3 activation. Consistently, activated Akt, a major negative regulator of apoptosis, was superphysiological in AAV-VEGF-B, whereas the proapoptotic intracellular mediators glycogen synthase kinase (GSK)-3β and FoxO3a (Akt targets) were activated in AAV-control, but not in AAV-VEGF-B. Cardiac VEGFR-1 expression was reduced 4-fold in all paced dogs, suggesting that exogenous VEGF-B167 exerted a compensatory receptor stimulation. The cytoprotective effects of VEGF-B167 were further elucidated in cultured rat neonatal cardiomyocytes exposed to 10−8 mol/L angiotensin II: VEGF-B167 prevented oxidative stress, loss of mitochondrial membrane potential, and, consequently, apoptosis. Conclusions We determined a novel, angiogenesis-unrelated cardioprotective effect of VEGF-B167 in nonischemic dilated cardiomyopathy, which limits apoptotic cell loss and delays the progression toward failure.
Background Alcohol Dependence (AD) shows evidence for genetic liability, but genes influencing risk remain largely unidentified. Methods We conducted a genomewide association study in 706 related AD cases and 1748 unscreened population controls from Ireland. We sought replication in 15,496 samples of European descent. We used model organisms to assess the role of orthologous genes in ethanol response behaviors. We tested one primate-specific gene for expression differences in case/control post-mortem brain tissue. Results We detected significant association in COL6A3 and suggestive association in two previously implicated loci, KLF12 and RYR3. None of these signals are significant in replication. A suggestive signal in the long noncoding RNA LOC339975 is significant in case:control meta-analysis, but not in a population sample. Knockdown of a COL6A3 ortholog in C. elegans reduced ethanol sensitivity. Col6a3 expression correlated with handling-induced convulsions in mice. Loss of function of the KLF12 ortholog in C. elegans impaired development of acute functional tolerance. Klf12 expression correlated with locomotor activation following ethanol injection in mice. Loss of function of the RYR3 ortholog reduced ethanol sensitivity in C. elegans and rapid tolerance in Drosophila. The ryanodine receptor antagonist dantrolene reduced motivation to self-administer ethanol in rats. Expression of LOC339975 does not differ between cases and controls but is reduced in carriers of the associated rs11726136 allele in nucleus accumbens. Conclusions We detect association between AD and COL6A3, KLF12, RYR3 and LOC339975. Despite non-replication of COL6A3, KLF12 and RYR3 signals, orthologs of these genes influence behavioral response to ethanol in model organisms, suggesting potential involvement in human ethanol response and AD liability. The associated LOC339975 allele may influence gene expression in human nucleus accumbens. Although the functions of long noncoding RNAs are poorly understood, there is mounting evidence implicating these genes in multiple brain functions and disorders.
Topical intra-nasal sprays are amongst the most commonly prescribed therapeutic options for sinonasal diseases in humans. However, inconsistency and ambiguity in instructions show a lack of definitive knowledge on best spray use techniques. In this study, we have identified a new usage strategy for nasal sprays available over-the-counter, that registers an average 8-fold improvement in topical delivery of drugs at diseased sites, when compared to prevalent spray techniques. The protocol involves re-orienting the spray axis to harness inertial motion of particulates and has been developed using computational fluid dynamics simulations of respiratory airflow and droplet transport in medical imaging-based digital models. Simulated dose in representative models is validated through in vitro spray measurements in 3D-printed anatomic replicas using the gamma scintigraphy technique. This work breaks new ground in proposing an alternative user-friendly strategy that can significantly enhance topical delivery inside human nose. While these findings can eventually translate into personalized spray usage instructions and hence merit a change in nasal standard-of-care, this study also demonstrates how relatively simple engineering analysis tools can revolutionize everyday healthcare. Finally, with respiratory mucosa as the initial coronavirus infection site, our findings are relevant to intra-nasal vaccines that are in-development, to mitigate the COVID-19 pandemic.
Recchia FA. Reverse changes in cardiac substrate oxidation in dogs recovering from heart failure. Am J Physiol Heart Circ Physiol 295: H2098 -H2105, 2008. First published September 26, 2008 doi:10.1152/ajpheart.00471.2008.-When recovering from heart failure (HF), the myocardium displays a marked plasticity and can regain normal gene expression and function; however, recovery of substrate oxidation capacity has not been explored. We tested whether cardiac functional recovery is matched by normalization of energy substrate utilization during post-HF recovery. HF was induced in dogs by pacing the left ventricle (LV) at 210 -240 beats/min for 4 wk. Tachycardia was discontinued, and the heart was allowed to recover. An additional group was studied in HF, and healthy dogs served as controls (n ϭ 8/group). Cardiac free fatty acids (FFAs) and glucose oxidation were measured with [ 3 H]oleate and [ 14 C]glucose. At 10 days of recovery, hemodynamic parameters returned to control values; however, the contractile response to dobutamine remained depressed, LV end-diastolic volume was 28% higher than control, and the heart mass-to-body mass ratio was increased (9.8 Ϯ 0.4 vs. 7.5 Ϯ 0.2 g/kg, P Ͻ 0.05). HF increased glucose oxidation (76.8 Ϯ 19.7 nmol ⅐ min Ϫ1 ⅐ g Ϫ1 ) and decreased FFA oxidation (20.7 Ϯ 6.4 nmol ⅐ min Ϫ1 ⅐ g Ϫ1 ), compared with normal dogs (24.5 Ϯ 6.3 and 51.7 Ϯ 9.6 nmol ⅐ min Ϫ1 ⅐ g Ϫ1 , respectively), and reversed to normal values at 10 days of recovery (25.4 Ϯ 6.0 and 46.6 Ϯ 6.7 nmol ⅐ min Ϫ1 ⅐ g Ϫ1 , respectively). However, similar to HF, the recovered dogs failed to increase glucose and fatty acid uptake in response to pacing stress. The activity of myocardial citrate synthase and aconitase was significantly decreased during recovery compared with that in control dogs (58 and 27% lower, respectively, P Ͻ 0.05), indicating a persistent reduction in mitochondrial oxidative capacity. In conclusion, cardiac energy substrate utilization is normalized in the early stage of post-HF recovery at baseline, but not under stress conditions. dilated cardiomyopathy; fatty acids; glucose; tachypacing THE CAPACITY OF THE FAILING heart to recover and restore, at least in part, a normal structure and function has been well demonstrated, both in animal models (12,13,26,28) and in patients (3,25). In pacing-induced heart failure (HF), an established model of dilated cardiomyopathy, hemodynamic and neurohormonal alterations, as well as myocyte function, return to control level within the first 2 wk of recovery after discontinuation of cardiac stimulation (28). Moreover, a number of studies have been performed in end-stage HF patients sustained with mechanical left ventricular (LV) assist devices while awaiting cardiac transplantation. The availability of ventricular tissue samples collected during the procedures of assist device implantation and removal has stimulated a strong interest in the molecular and cellular alterations occurring before and after mechanical unloading. Mechanical assistance favors reverse remodeling at...
Objectives: To determine if high-resolution T2-weighted (HRT2) magnetic resonance imaging (MRI) is a comparably accurate and economical alternative to the gold standard of contrast-enhanced T1-weighted (T1C) MRI for surveillance of know vestibular schwannomas (VSs).Study Design: Retrospective case-control analysis, systematic review, and economic evaluation. Methods: Vestibular schwannoma size in anteroposterior, mediolateral, and superoinferior axes were measured by two neuroradiologists, both blinded to previous measurements, for 50 randomized patients with T1C and HRT2 on two separate occasions. Measurements were assessed by Pearson product-moment correlation coefficients, and differences were analyzed by Student t test. Once the data were analyzed, appropriate economic evaluation was performed utilizing institutional-, federal-, and literature-based estimates of cost and incidence/prevalence.Results: Pearson correlations (r) between T1C and HRT2 were 0.991 and 0.973 for radiologists 1 and 2, respectively, with no statistically significant differences (P 0.05) between imaging techniques. Intraobserver and interobserver reliability estimates (j) were 0.88 to 1 for both T1C and HRT2, indicating very high reliability. Cost-minimization analysis demonstrated cost and charge differences of $148.02 and $1,284 per patient per scan, respectively. This represents an overall cost and charge savings for this 50-patient cohort of $7,401 and $64,200, respectively.Conclusion: HRT2 imaging is a highly reliable and lower-cost alternative to T1C for follow-up surveillance scans in patients with VS.
Evidence is accumulating to support a potentially important role for purinergic (P2X) receptors in heart failure (HF). We tested the hypothesis that a hydrolysis-resistant nucleotide analog with agonist activity at myocardial P2X receptors (P2XRs) improves the systolic HF phenotype in mouse and dog models. We developed a hydrolysis-resistant adenosine monophosphate derivative, (1ЈS,2R,3S,4ЈR,5ЈS)-4-(6-amino-2-chloro-9H-purin-9-yl)-1-[phosphoryloxymethyl] bicycle[3.1.0]hexane-2,3-diol) (MRS2339), with agonist activity at native cardiac P2XRs. Chronic MRS2339 infusion in postinfarct and calsequestrin (CSQ) mice with HF resulted in higher rates of pressure change (ϩdP/dt), left ventricle (LV)-developed pressure, and cardiac output in an in vitro working heart model. Heart function in vivo, as determined by echocardiography-derived fractional shortening, was also improved in MRS2339-infused mice. The beneficial effect of MRS2339 was dose-dependent and was identical to that produced by cardiac myocyte-specific overexpression of the P2X 4 receptor. The HF improvement was associated with the preservation of LV wall thickness in both systole and diastole in postinfarct and CSQ mice. In dogs with pacing-induced HF, MRS2339 infusion reduced left ventricular end-diastolic pressure, improved arterial oxygenation, and increased ϩdP/dt. MRS2339 treatment also decreased LV chamber size in mice and dogs with HF. In murine and canine models of systolic HF, in vivo administration of a P2X nucleotide agonist improved contractile function and cardiac performance. These actions were associated with preserved LV wall thickness and decreased LV remodeling. The data are consistent with a role of cardiac P2XRs in mediating the beneficial effect of this agonist.Interest has grown in the physiological role of purinergic (P2) receptors for extracellular ATP within the cardiovascular system. There are two subfamilies of P2 receptors: ligandgated ion channel and G protein-coupled receptors, termed P2X and P2Y, respectively (North, 2002;Abbracchio et al., 2006). Seven subtypes of P2X (P2X 1 -7 ) receptors have been identified by molecular cloning. The various cloned P2Y receptors are coupled to phospholipase C (PLC) (for P2Y 1 , P2Y 2 , P2Y 4 , P2Y 6 ), PLC and Gs (for P2Y 11 ) (Communi et al., 1997;Hollopeter et al., 2001;Zhang et al., 2001), and G i (P2Y 12 , P2Y 13 , P2Y 14 ). Members of both the P2X and P2Y families are expressed in the heart (Erlinge and Burnstock, 2008). P2X 1 receptor expression is increased in the left atria of patients with dilated cardiomyopathy (Berry et al., 1999), whereas the P2Y 11 receptor is present in all four chambers of the heart (Communi et al., 1997).In the heart, extracellular ATP can elicit an increase in
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