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1.
J Med Case Rep ; 17(1): 142, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37069616

RESUMO

BACKGROUND: Polymorphous adenocarcinoma is the third most common malignant salivary gland tumor. Within polymorphous adenocarcinoma, cribriform adenocarcinoma of salivary glands is a rare subtype and resembles papillary thyroid carcinoma histopathologically. Diagnostically, cribriform adenocarcinoma of salivary glands is challenging for pathologists and surgeons alike as initial presentation and cytologic nuclear features can be easily confused with papillary thyroid carcinoma arising from a thyroglossal duct remnant or lingual thyroid. CASE PRESENTATION: A healthy 64-year-old Caucasian woman presented to a community otolaryngologist with a 4-year history of progressive postnasal drip, globus sensation, and eventual dysphonia. Flexible fiberoptic laryngoscopy showed a large, smooth, vallecular lesion filling the oropharynx. Computed tomography imaging of the neck showed a rounded heterogeneous mass centered within the right aspect of the oropharynx measuring 4.2 × 4.4 × 4.5 cm. Fine needle aspiration biopsy was suspicious for papillary carcinoma due to microscopic findings of malignant cells, nuclear grooves, and a powdery chromatin pattern. In the operating room, the tumor was resected en bloc using a lateral pharyngotomy approach with partial resection of the right lateral hyoid. A limited cervical lymphadenectomy was performed to facilitate the lateral pharyngotomy approach and two out of three lymph nodes demonstrated regional metastatic disease. Nuclear grooves, nuclear membrane notching, and occasional intranuclear pseudoinclusions were identified, which are overlapping histopathological characteristics of papillary thyroid carcinoma and cribriform adenocarcinoma of salivary glands. It was negative for thyroglobulin and thyroid transcription factor-1, which was in keeping with cribriform adenocarcinoma of salivary glands rather than papillary thyroid carcinoma. CONCLUSION: It is difficult to distinguish cribriform adenocarcinoma of salivary glands from papillary thyroid carcinoma solely by cytology, and the distinct characteristics of regional lymph node metastasis coupled with nuanced histologic differences should be emphasized in the evaluation of patients presenting with neck lymphadenopathy and an unknown primary or tongue mass. If sufficient fine needle aspiration biopsy material is available, thyroid transcription factor-1, thyroglobulin, or molecular testing may prove useful in differentiating cribriform adenocarcinoma of salivary glands from papillary thyroid carcinoma. A misdiagnosis of papillary thyroid carcinoma may lead to inappropriate treatment including unnecessary thyroidectomy. Therefore, it is critical for both pathologists and surgeons to be aware of this uncommon entity to avoid misdiagnosis and subsequent mismanagement.


Assuntos
Adenocarcinoma , Neoplasias da Glândula Tireoide , Feminino , Humanos , Pessoa de Meia-Idade , Tireoglobulina , Câncer Papilífero da Tireoide/diagnóstico , Câncer Papilífero da Tireoide/cirurgia , Câncer Papilífero da Tireoide/patologia , Glândulas Salivares Menores/patologia , Glândulas Salivares Menores/cirurgia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/cirurgia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Fatores de Transcrição
2.
Laryngoscope ; 133(10): 2597-2602, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36651328

RESUMO

OBJECTIVES: Bone resorption of more conventional vascularized bone grafts have been well described showing minimal resorption over time. Few studies have evaluated osseous union and bone resorption in scapula tip free flaps (STFF) in the reconstruction of mandibulectomy defects. We aimed to describe our series on STFF with respect to osseous union and bone resorption over time. METHODS: Retrospective chart review of patients receiving STFF from January 2014-January 2017 (n = 25). A neuroradiologist analyzed follow-up CT scans to assess (1) STFF complete, partial, or no osseous union with native mandible and (2) STFF volume change over time in a subset with multiple follow-up scans (n = 18). RESULTS: Twenty-three of 25 patients (92%) showed complete or partial STFF osseous union with native mandible either distally or proximally. STFF volume change ranged from +4.8 to -54% (median -0.5%) over median follow-up interval of 23 months. History of chemoradiation therapy, bisphophonate use, sex, age, or smoking history did not correlate with bone resorption. CONCLUSIONS: STFFs shows high rates of osseous union and limited bone resorption that is equivalent to, or less than, vascularized fibular and iliac crest flaps. Clinically, this translates into both optimal healing and functional and cosmetic outcomes, especially in the setting of prior therapies. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:2597-2602, 2023.


Assuntos
Reabsorção Óssea , Retalhos de Tecido Biológico , Neoplasias Mandibulares , Reconstrução Mandibular , Humanos , Retalhos de Tecido Biológico/transplante , Estudos Retrospectivos , Neoplasias Mandibulares/cirurgia , Reconstrução Mandibular/métodos , Osseointegração , Mandíbula/cirurgia , Escápula/transplante , Reabsorção Óssea/etiologia , Reabsorção Óssea/cirurgia , Transplante Ósseo/métodos
3.
Addict Biol ; 26(6): e13071, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34164896

RESUMO

Our lab and others have shown that chronic alcohol use leads to gene and miRNA expression changes across the mesocorticolimbic (MCL) system. Circular RNAs (circRNAs) are noncoding RNAs that form closed-loop structures and are reported to alter gene expression through miRNA sequestration, thus providing a potentially novel neurobiological mechanism for the development of alcohol dependence (AD). Genome-wide expression of circRNA was assessed in the nucleus accumbens (NAc) from 32 AD-matched cases/controls. Significant circRNAs (unadj. p ≤ 0.05) were identified via regression and clustered in circRNA networks via weighted gene co-expression network analysis (WGCNA). CircRNA interactions with previously generated mRNA and miRNA were detected via correlation and bioinformatic analyses. Significant circRNAs (N = 542) clustered in nine significant AD modules (FWER p ≤ 0.05), within which we identified 137 circRNA hubs. We detected 23 significant circRNA-miRNA-mRNA interactions (FDR ≤ 0.10). Among these, circRNA-406742 and miR-1200 significantly interact with the highest number of mRNA, including genes associated with neuronal functioning and alcohol addiction (HRAS, PRKCB, HOMER1, and PCLO). Finally, we integrate genotypic information that revealed 96 significant circRNA expression quantitative trait loci (eQTLs) (unadj. p ≤ 0.002) that showed significant enrichment within recent alcohol use disorder (AUD) and smoking genome-wide association study (GWAS). To our knowledge, this is the first study to examine the role of circRNA in the neuropathology of AD. We show that circRNAs impact mRNA expression by interacting with miRNA in the NAc of AD subjects. More importantly, we provide indirect evidence for the clinical importance of circRNA in the development of AUD by detecting a significant enrichment of our circRNA eQTLs among GWAS of substance abuse.


Assuntos
Alcoolismo/genética , MicroRNAs/biossíntese , Núcleo Accumbens/patologia , RNA Circular/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/genética , Estudo de Associação Genômica Ampla , Humanos , Fumar/patologia
4.
PLoS One ; 15(12): e0243857, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33332381

RESUMO

Chronic alcohol abuse has been linked to the disruption of executive function and allostatic conditioning of reward response dysregulation in the mesocorticolimbic pathway (MCL). Here, we analyzed genome-wide mRNA and miRNA expression from matched cases with alcohol dependence (AD) and controls (n = 35) via gene network analysis to identify unique and shared biological processes dysregulated in the prefrontal cortex (PFC) and nucleus accumbens (NAc). We further investigated potential mRNA/miRNA interactions at the network and individual gene expression levels to identify the neurobiological mechanisms underlying AD in the brain. By using genotyped and imputed SNP data, we identified expression quantitative trait loci (eQTL) uncovering potential genetic regulatory elements for gene networks associated with AD. At a Bonferroni corrected p≤0.05, we identified significant mRNA (NAc = 6; PFC = 3) and miRNA (NAc = 3; PFC = 2) AD modules. The gene-set enrichment analyses revealed modules preserved between PFC and NAc to be enriched for immune response processes, whereas genes involved in cellular morphogenesis/localization and cilia-based cell projection were enriched in NAc modules only. At a Bonferroni corrected p≤0.05, we identified significant mRNA/miRNA network module correlations (NAc = 6; PFC = 4), which at an individual transcript level implicated miR-449a/b as potential regulators for cellular morphogenesis/localization in NAc. Finally, we identified eQTLs (NAc: mRNA = 37, miRNA = 9; PFC: mRNA = 17, miRNA = 16) which potentially mediate alcohol's effect in a brain region-specific manner. Our study highlights the neurotoxic effects of chronic alcohol abuse as well as brain region specific molecular changes that may impact the development of alcohol addiction.


Assuntos
Alcoolismo/genética , Redes Reguladoras de Genes , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/metabolismo , Doença Crônica , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Metalotioneína/genética , Metalotioneína/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Núcleo Accumbens/patologia , Córtex Pré-Frontal/patologia , Locos de Características Quantitativas/genética
5.
Alcohol Clin Exp Res ; 44(12): 2468-2480, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33067813

RESUMO

BACKGROUND: Long noncoding RNA (lncRNA) have been implicated in the etiology of alcohol use. Since lncRNA provide another layer of complexity to the transcriptome, assessing their expression in the brain is the first critical step toward understanding lncRNA functions in alcohol use and addiction. Thus, we sought to profile lncRNA expression in the nucleus accumbens (NAc) in a large postmortem alcohol brain sample. METHODS: LncRNA and protein-coding gene (PCG) expressions in the NAc from 41 subjects with alcohol dependence (AD) and 41 controls were assessed via a regression model. Weighted gene coexpression network analysis was used to identify lncRNA and PCG networks (i.e., modules) significantly correlated with AD. Within the significant modules, key network genes (i.e., hubs) were also identified. The lncRNA and PCG hubs were correlated via Pearson correlations to elucidate the potential biological functions of lncRNA. The lncRNA and PCG hubs were further integrated with GWAS data to identify expression quantitative trait loci (eQTL). RESULTS: At Bonferroni adj. p-value ≤ 0.05, we identified 19 lncRNA and 5 PCG significant modules, which were enriched for neuronal and immune-related processes. In these modules, we further identified 86 and 315 PCG and lncRNA hubs, respectively. At false discovery rate (FDR) of 10%, the correlation analyses between the lncRNA and PCG hubs revealed 3,125 positive and 1,860 negative correlations. Integration of hubs with genotype data identified 243 eQTLs affecting the expression of 39 and 204 PCG and lncRNA hubs, respectively. CONCLUSIONS: Our study identified lncRNA and gene networks significantly associated with AD in the NAc, coordinated lncRNA and mRNA coexpression changes, highlighting potentially regulatory functions for the lncRNA, and our genetic (cis-eQTL) analysis provides novel insights into the etiological mechanisms of AD.


Assuntos
Alcoolismo/metabolismo , Núcleo Accumbens/metabolismo , RNA Longo não Codificante/metabolismo , Alcoolismo/genética , Estudos de Casos e Controles , Estudo de Associação Genômica Ampla , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Locos de Características Quantitativas , RNA Longo não Codificante/genética , Transcriptoma
6.
Sci Rep ; 10(1): 10568, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601278

RESUMO

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.


Assuntos
Administração por Inalação , Administração Intranasal/métodos , Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Sistemas de Liberação de Medicamentos/métodos , Sprays Nasais , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , COVID-19 , Simulação por Computador , Infecções por Coronavirus/virologia , Humanos , Hidrodinâmica , Cavidade Nasal/anatomia & histologia , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/virologia , Nebulizadores e Vaporizadores , Seios Paranasais/efeitos dos fármacos , Seios Paranasais/virologia , Pneumonia Viral/virologia , SARS-CoV-2 , Vacinas Virais/administração & dosagem
7.
JAMA Otolaryngol Head Neck Surg ; 144(11): 967-975, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29710215

RESUMO

Importance: Clinical trials that deintensify treatment for patients with suspected human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) use p16 expression to identify HPV-mediated tumors and guide treatment. While p16 staining has a strong correlation with good outcomes, approximately 12% of p16-positive patients have recurrent disease. Biomarkers that reveal tumor-specific characteristics, such as nodal involvement, may change therapy decisions. Objective: To assess whether if a tumor-specific genetic signature exists for node-negative vs node-positive HPV 16-positive/p16-positive OPSCCs. Design, Setting, and Participants: This was a retrospective cohort study with randomized case selection for p16 OPSCCs undertaken at a university-based, tertiary care cancer center. Samples were collected from patients with p16-positive OPSCC. A total of 21 HPV 16/p16-positive tumors were used in this study. Main Outcomes and Measures: Gene expression profiles of node-negative vs node-positive tumor samples were evaluated using a differential expression analysis approach and the sensitivity and specificity of a molecular signature was determined. Results: Among the 21 patients in the study (3 women, 18 men; mean [SD] age, 54.6 [9.6] years), 6 had node-negative disease and 15 had node-positive disease. Using differential expression analysis, we found 146 genes that were significantly different in patients with node-negative disease vs those with node-positive disease, of which 15 genes were used to create a genetic signature that could distinguish node-negative-like from node-positive-like disease. The resultant molecular signature has a sensitivity of 88.2% (95% CI, 63.6%-98.5%) and specificity of 85.7% (95% CI, 42.1%-99.6%). The positive likelihood ratio of this signature was 6.1 (95% CI, 1.0-38.2) and the negative likelihood ratio was 0.1 (95% CI, 0.04-0.5). Given this population's prevalence of node-positive disease of 70.8%, the positive- and negative-predicative values for this gene signature were 93.7% (95% CI, 70.8%-98.9%) and 75.0% (95% CI, 44.1%-92.0%), respectively. In addition, we developed a gene signature using agnostic, machine learning software that identified a 40-gene profile that predicts node-negative disease from node-positive disease (area under the curve, 0.93; 95% CI, 0.63-1.00). Conclusions and Relevance: Many HPV-16 and p16-positive tumors are treated as "lower-risk," but they do not have similar genetic compositions at the biological level. The identification of subgroups with unique expression patterns, such as those with nodal metastases, may guide physicians toward alternative or more aggressive therapies. In our study, unguided clustering suggested that that the larger biological characteristics of a tumor could be a better prognostic biomarker.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/virologia , Perfilação da Expressão Gênica , Papillomavirus Humano 16/genética , Metástase Linfática , Neoplasias Orofaríngeas/genética , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/virologia , RNA/genética , Feminino , Papillomavirus Humano 16/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Prognóstico , Estudos Prospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Laryngoscope ; 128(1): 202-209, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28397265

RESUMO

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 (κ) 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. LEVEL OF EVIDENCE: 2C. Laryngoscope, 128:202-209, 2018.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neuroma Acústico/diagnóstico por imagem , Estudos de Casos e Controles , Meios de Contraste , Análise Custo-Benefício , Feminino , Gadolínio , Gadolínio DTPA , Compostos Heterocíclicos , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos , Reprodutibilidade dos Testes , Estudos Retrospectivos
9.
Alcohol Clin Exp Res ; 41(5): 911-928, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28226201

RESUMO

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 1,748 unscreened population controls from Ireland. We sought replication in 15,496 samples of European descent. We used model organisms (MOs) to assess the role of orthologous genes in ethanol (EtOH)-response behaviors. We tested 1 primate-specific gene for expression differences in case/control postmortem brain tissue. RESULTS: We detected significant association in COL6A3 and suggestive association in 2 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 Caenorhabditis elegans reduced EtOH 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 (AFT). Klf12 expression correlated with locomotor activation following EtOH injection in mice. Loss of function of the RYR3 ortholog reduced EtOH sensitivity in C. elegans and rapid tolerance in Drosophila. The ryanodine receptor antagonist dantrolene reduced motivation to self-administer EtOH 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 (NAc). CONCLUSIONS: We detect association between AD and COL6A3, KLF12, RYR3, and LOC339975. Despite nonreplication of COL6A3, KLF12, and RYR3 signals, orthologs of these genes influence behavioral response to EtOH in MOs, suggesting potential involvement in human EtOH response and AD liability. The associated LOC339975 allele may influence gene expression in human NAc. Although the functions of long noncoding RNAs are poorly understood, there is mounting evidence implicating these genes in multiple brain functions and disorders.


Assuntos
Alcoolismo/genética , Etanol/administração & dosagem , Loci Gênicos/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Modelos Animais , Adulto , Alcoolismo/diagnóstico , Alcoolismo/epidemiologia , Animais , Caenorhabditis elegans , Estudos de Casos e Controles , Drosophila , Feminino , Loci Gênicos/efeitos dos fármacos , Predisposição Genética para Doença/epidemiologia , Humanos , Irlanda/epidemiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Pessoa de Meia-Idade , Ratos
10.
PLoS One ; 10(9): e0137671, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26381263

RESUMO

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.


Assuntos
Alcoolismo/genética , Redes Reguladoras de Genes , MicroRNAs/genética , Núcleo Accumbens/metabolismo , Locos de Características Quantitativas , RNA Mensageiro/genética , Alcoolismo/metabolismo , Astrócitos/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Neurônios/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais/fisiologia , Transcriptoma , Regulação para Cima
12.
Circ Res ; 106(12): 1893-903, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20431055

RESUMO

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-B(167) cDNA (10(12) 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 Po(2). 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 alpha-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)-3beta 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-B(167) exerted a compensatory receptor stimulation. The cytoprotective effects of VEGF-B(167) were further elucidated in cultured rat neonatal cardiomyocytes exposed to 10(-8) mol/L angiotensin II: VEGF-B(167) prevented oxidative stress, loss of mitochondrial membrane potential, and, consequently, apoptosis. CONCLUSIONS: We determined a novel, angiogenesis-unrelated cardioprotective effect of VEGF-B(167) in nonischemic dilated cardiomyopathy, which limits apoptotic cell loss and delays the progression toward failure.


Assuntos
Cardiomiopatias/complicações , Progressão da Doença , Insuficiência Cardíaca/prevenção & controle , Miocárdio/metabolismo , Fator B de Crescimento do Endotélio Vascular/genética , Fator B de Crescimento do Endotélio Vascular/metabolismo , Adenoviridae/genética , Animais , Cardiomiopatias/metabolismo , Células Cultivadas , DNA Complementar/genética , Modelos Animais de Doenças , Cães , Técnicas de Transferência de Genes , Insuficiência Cardíaca/metabolismo , Masculino , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Neuropilina-1/metabolismo , Estresse Oxidativo/fisiologia , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
J Pharmacol Exp Ther ; 333(3): 920-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20200116

RESUMO

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, (1'S,2R,3S,4'R,5'S)-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 (+dP/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 +dP/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.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Coração/efeitos dos fármacos , Receptores Purinérgicos P2/efeitos dos fármacos , Animais , Estimulação Cardíaca Artificial , Cardiomiopatia Dilatada/tratamento farmacológico , Cães , Insuficiência Cardíaca/diagnóstico por imagem , Testes de Função Cardíaca , Hemodinâmica/efeitos dos fármacos , Infusões Intravenosas , Masculino , Camundongos , Camundongos Transgênicos , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Receptores Purinérgicos P2/biossíntese , Receptores Purinérgicos P2/genética , Taquicardia/tratamento farmacológico , Ultrassonografia , Função Ventricular Esquerda/efeitos dos fármacos
14.
Am J Physiol Heart Circ Physiol ; 295(5): H2098-105, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18820029

RESUMO

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 = 8/group). Cardiac free fatty acids (FFAs) and glucose oxidation were measured with [3H]oleate and [14C]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 +/- 0.4 vs. 7.5 +/- 0.2 g/kg, P < 0.05). HF increased glucose oxidation (76.8 +/- 19.7 nmol.min(-1).g(-1)) and decreased FFA oxidation (20.7 +/- 6.4 nmol.min(-1).g(-1)), compared with normal dogs (24.5 +/- 6.3 and 51.7 +/- 9.6 nmol.min(-1).g(-1), respectively), and reversed to normal values at 10 days of recovery (25.4 +/- 6.0 and 46.6 +/- 6.7 nmol.min(-1).g(-1), 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 < 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.


Assuntos
Metabolismo Energético , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica , Mitocôndrias Cardíacas/metabolismo , Miocárdio/metabolismo , Aconitato Hidratase/metabolismo , Acil-CoA Desidrogenase/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Animais , Estimulação Cardíaca Artificial , Citrato (si)-Sintase/metabolismo , Modelos Animais de Doenças , Cães , Ácidos Graxos não Esterificados/metabolismo , Glucose/metabolismo , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/metabolismo , Hemodinâmica/efeitos dos fármacos , Masculino , Mitocôndrias Cardíacas/enzimologia , Contração Miocárdica , Miocárdio/enzimologia , Miocárdio/patologia , Oxirredução , Recuperação de Função Fisiológica , Fatores de Tempo , Ultrassonografia , Remodelação Ventricular
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