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Two of the most prevalent neurodegenerative disorders (NDDs), Alzheimer's disease (AD) and Parkinson's disease (PD), present significant challenges to healthcare systems worldwide. While the etiologies of AD and PD differ, both diseases share commonalities in synaptic dysfunction, thereby focusing attention on the role of neurotransmitters. The possible functions that platelets may play in neurodegenerative illnesses including PD and AD are becoming more acknowledged. In AD, platelets have been investigated for their ability to generate amyloid-ß (Aß) peptides, contributing to the formation of neurotoxic plaques. Moreover, platelets are considered biomarkers for early AD diagnosis. In PD, platelets have been studied for their involvement in oxidative stress and mitochondrial dysfunction, which are key factors in the disease's pathogenesis. Emerging research shows that platelets, which release glutamate upon activation, also play a role in these disorders. Decreased glutamate uptake in platelets has been observed in Alzheimer's and Parkinson's patients, pointing to a systemic dysfunction in glutamate handling. This paper aims to elucidate the critical role that glutamate receptors play in the pathophysiology of both AD and PD. Utilizing data from clinical trials, animal models, and cellular studies, we reviewed how glutamate receptors dysfunction contributes to neurodegenerative (ND) processes such as excitotoxicity, synaptic loss, and cognitive impairment. The paper also reviews all current medications including glutamate receptor antagonists for AD and PD, highlighting their mode of action and limitations. A deeper understanding of glutamate receptor involvement including its systemic regulation by platelets could open new avenues for more effective treatments, potentially slowing disease progression and improving patient outcomes.
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Doença de Alzheimer , Doença de Parkinson , Animais , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Doença de Alzheimer/patologia , Ácido Glutâmico , Receptores de GlutamatoRESUMO
Patients with inflammatory bowel disease (IBD) are susceptible to colitis-associated cancer (CAC). Chronic inflammation promotes the risk for CAC. In contrast, mucosal healing predicts improved prognosis in IBD and reduced risk of CAC. However, the molecular integration among colitis, mucosal healing, and CAC remains poorly understood. Claudin-2 (CLDN2) expression is upregulated in IBD; however, its role in CAC is not known. The current study was undertaken to examine the role for CLDN2 in CAC. The AOM/DSS-induced CAC model was used with WT and CLDN2-modified mice. High-throughput expression analyses, murine models of colitis/recovery, chronic colitis, ex vivo crypt culture, and pharmacological manipulations were employed in order to increase our mechanistic understanding. The Cldn2KO mice showed significant inhibition of CAC despite severe colitis compared with WT littermates. Cldn2 loss also resulted in impaired recovery from colitis and increased injury when mice were subjected to intestinal injury by other methods. Mechanistic studies demonstrated a possibly novel role of CLDN2 in promotion of mucosal healing downstream of EGFR signaling and by regulation of Survivin expression. An upregulated CLDN2 expression protected from CAC and associated positively with crypt regeneration and Survivin expression in patients with IBD. We demonstrate a potentially novel role of CLDN2 in promotion of mucosal healing in patients with IBD and thus regulation of vulnerability to colitis severity and CAC, which can be exploited for improved clinical management.
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Neoplasias Associadas a Colite , Colite , Doenças Inflamatórias Intestinais , Animais , Humanos , Camundongos , Claudina-2/genética , Claudina-2/metabolismo , Colite/induzido quimicamente , Colite/complicações , Colite/genética , Neoplasias Associadas a Colite/complicações , Neoplasias Associadas a Colite/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/metabolismo , Camundongos Endogâmicos C57BL , Survivina/metabolismoRESUMO
Background: Posttraumatic stress disorder (PTSD) is a mental health condition triggered by exposure to traumatic events in an individual's life. Patients with PTSD are also at a higher risk for comorbidities. However, it is not well understood how PTSD affects human health and/or promotes the risk for comorbidities. Nevertheless, patients with PTSD harbor a proinflammatory milieu and dysbiotic gut microbiota. Gut barrier integrity helps to maintain normal gut homeostasis and its dysregulation promotes gut dysbiosis and inflammation. Methods: We used a mouse model of repeated social defeat stress (RSDS), a preclinical model of PTSD. Behavioral studies, metagenomics analysis of the microbiome, gut permeability assay (on mouse colon, using an Ussing chamber), immunoblotting, and immunohistochemical analyses were performed. Polarized intestinal epithelial cells and 3-dimensional crypt cultures were used for mechanistic analysis. Results: The RSDS mice harbor a heightened proinflammatory gut environment and microbiota dysbiosis. The RSDS mice further showed significant dysregulation of gut barrier functions, including transepithelial electrical resistance, mucin homeostasis, and antimicrobial responses. RSDS mice also showed a specific increase in intestinal expression of claudin-2, a tight junction protein, and epinephrine, a stress-induced neurotransmitter. Treating intestinal epithelial cells or 3-dimensional cultured crypts with norepinephrine or intestinal luminal contents (fecal contents) upregulated claudin-2 expression and inhibited transepithelial electrical resistance. Conclusions: Traumatic stress induces dysregulation of gut barrier functions, which may underlie the observed gut microbiota changes and proinflammatory gut milieu, all of which may have an interdependent effect on the health and increased risk of comorbidities in patients with PTSD.
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Cytomegalovirus (CMV) is a widely prevalent herpesvirus that reaches seroprevalence rates of up to 95% in several parts of the world. The majority of CMV infections are asymptomatic, albeit they have severe detrimental effects on immunocompromised individuals. Congenital CMV infection is a leading cause of developmental abnormalities in the USA. CMV infection is a significant risk factor for cardiovascular diseases in individuals of all ages. Like other herpesviruses, CMV regulates cell death for its replication and establishes and maintains a latent state in the host. Although CMV-mediated regulation of cell death is reported by several groups, it is unknown how CMV infection affects necroptosis and apoptosis in cardiac cells. Here, we infected primary cardiomyocytes, the contractile cells in the heart, and primary cardiac fibroblasts with wild-type and cell-death suppressor deficient mutant CMVs to determine how CMV regulates necroptosis and apoptosis in cardiac cells. Our results reveal that CMV infection prevents TNF-induced necroptosis in cardiomyocytes; however, the opposite phenotype is observed in cardiac fibroblasts. CMV infection also suppresses inflammation, reactive oxygen species (ROS) generation, and apoptosis in cardiomyocytes. Furthermore, CMV infection improves mitochondrial biogenesis and viability in cardiomyocytes. We conclude that CMV infection differentially affects the viability of cardiac cells.
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Sonodynamic therapy (SDT) is an application of focused ultrasound (FUS) that enables a sonosensitizing agent to prime tumors for increased sensitivity during sonication. Unfortunately, current clinical treatments for glioblastoma (GBM) are lacking, leading to low long-term survival rates among patients. SDT is a promising method for treating GBM in an effective, noninvasive, and tumor-specific manner. Sonosensitizers preferentially enter tumor cells compared to the surrounding brain parenchyma. The application of FUS in the presence of a sonosensitizing agent generates reactive oxidative species resulting in apoptosis. Although this therapy has been shown previously to be effective in preclinical studies, there is a lack of established standardized parameters. Standardized methods are necessary to optimize this therapeutic strategy for preclinical and clinical use. In this paper, we detail the protocol to perform SDT in a preclinical GBM rodent model using magnetic resonance-guided FUS (MRgFUS). MRgFUS is an important feature of this protocol, as it allows for specific targeting of a brain tumor without the need for invasive surgeries (e.g., craniotomy). The benchtop device used here can focus on a specific location in three dimensions by clicking on a target on an MRI image, making target selection a straightforward process. This protocol will provide researchers with a standardized preclinical method for MRgFUS SDT, with the added flexibility to change and optimize parameters for translational research.
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Neoplasias Encefálicas , Glioblastoma , Terapia por Ultrassom , Camundongos , Animais , Glioblastoma/diagnóstico por imagem , Glioblastoma/terapia , Ultrassonografia , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/tratamento farmacológico , Encéfalo/patologia , Terapia por Ultrassom/métodos , Linhagem Celular TumoralRESUMO
Brain structural changes in HIV identified by voxel-based morphometry (VBM) alone could arise from a variety of causes that are difficult to distinguish without further information, such as cortical thickness (CT), gyrification index (GI) or sulcal depth (SD). Hence, our goal was to assess these additional metrics in HIV using high-resolution 3D T1-weighted images and investigate if surface-based morphometric (SBM) analysis would reveal significant changes in the gray matter (GM) and white matter (WM) volumes combined with alterations in cortical thickness (CT), gyrification index (GI), sulcal depth (SD). T1-w magnetization-prepared-rapid-acquisition gradient-echo (MP-RAGE) scans were acquired in 27 HIV-infected individuals on antiretroviral therapy (ART) and 15 HIV-uninfected healthy controls using a 3T MRI scanner equipped with a 16-channel head "receive" and a quadrature body "transmit" coil. Voxel-based and surface-based morphometric analyses were performed using the MATLAB based SPM Computational Anatomy Toolbox (CAT12.7(1700)). HIV-infected patients showed significantly altered GM and WM volumes, CT, GI, and SD, in multiple brain regions. This study showed the association of altered GM and WM volumes in local brain regions with the changes in region-wise CT, GI and SD measures of HIV-infected patients, especially in the parahippocampal and middle frontal regions as compared to uninfected healthy controls. The outcome of this study suggests that the findings of VBM may not necessarily indicate the volumetric shrinkage or increase alone, but might also be due to altered CT, GI, or SD. Correlation analysis showed a significantly accelerated gray matter loss with age in HIV-infected individuals compared to uninfected healthy controls.
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Infecções por HIV , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Infecções por HIV/diagnóstico por imagem , Infecções por HIV/tratamento farmacológicoRESUMO
Airway remodeling in asthma involves the hyperproliferation of airway smooth muscle (ASM) cells. However, the molecular signals that regulate ASM growth are not completely understood. Gq-coupled G protein-coupled receptor and receptor tyrosine kinase signaling regulate ASM cell proliferation via activation of phospholipase C, generation of inositol triphosphate (IP3) and diacylglycerol (DAG). Diacylglycerol kinase (DGK) converts DAG into phosphatidic acid (PA) and terminates DAG signaling while promoting PA-mediated signaling and function. Herein, we hypothesized that PA is a pro-mitogenic second messenger in ASM, and DGK inhibition reduces the conversion of DAG into PA resulting in inhibition of ASM cell proliferation. We assessed the effect of pharmacological inhibition of DGK on pro-mitogenic signaling and proliferation in primary human ASM cells. Pretreatment with DGK inhibitor I (DGKI) significantly inhibited platelet-derived growth factor-stimulated ASM cell proliferation. Anti-mitogenic effect of DGKI was associated with decreased mTOR signaling and expression of cyclin D1. Exogenous PA promoted pro-mitogenic signaling and rescued DGKI-induced attenuation of ASM cell proliferation. Finally, house dust mite (HDM) challenge in wild type mice promoted airway remodeling features, which were attenuated in DGKζ-/- mice. We propose that DGK serves as a potential drug target for mitigating airway remodeling in asthma.
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Remodelação das Vias Aéreas , Asma , Animais , Asma/metabolismo , Proliferação de Células , Ciclina D1/metabolismo , Diacilglicerol Quinase/genética , Diacilglicerol Quinase/metabolismo , Diglicerídeos/metabolismo , Humanos , Inositol/farmacologia , Camundongos , Mitógenos/farmacologia , Miócitos de Músculo Liso/metabolismo , Ácidos Fosfatídicos/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Tirosina Quinases/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fosfolipases Tipo C/metabolismoRESUMO
Pseudoprogression (PsP) refers to treatment-related clinico-radiologic changes mimicking true progression (TP) that occurs in patients with glioblastoma (GBM), predominantly within the first 6 months after the completion of surgery and concurrent chemoradiation therapy (CCRT) with temozolomide. Accurate differentiation of TP from PsP is essential for making informed decisions on appropriate therapeutic intervention as well as for prognostication of these patients. Conventional neuroimaging findings are often equivocal in distinguishing between TP and PsP and present a considerable diagnostic dilemma to oncologists and radiologists. These challenges have emphasized the need for developing alternative imaging techniques that may aid in the accurate diagnosis of TP and PsP. In this review, we encapsulate the current state of knowledge in the clinical applications of commonly used metabolic and physiologic magnetic resonance (MR) imaging techniques such as diffusion and perfusion imaging and proton spectroscopy in distinguishing TP from PsP. We also showcase the potential of promising imaging techniques, such as amide proton transfer and amino acid-based positron emission tomography, in providing useful information about the treatment response. Additionally, we highlight the role of "radiomics", which is an emerging field of radiology that has the potential to change the way in which advanced MR techniques are utilized in assessing treatment response in GBM patients. Finally, we present our institutional experiences and discuss future perspectives on the role of multiparametric MR imaging in identifying PsP in GBM patients treated with "standard-of-care" CCRT as well as novel/targeted therapies.
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Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Progressão da Doença , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Glioblastoma/terapia , Humanos , Imageamento por Ressonância Magnética/métodos , PrótonsRESUMO
Prolonged sitting in a mild hypercapnic environment impairs peripheral vascular function. The effects of sitting interruptions using passive or active skeletal muscle contractions are still unclear. Therefore, we sought to examine the vascular effects of brief periods (2 min every half hour) of passive and active lower limb movement to interrupt prolonged sitting with mild hypercapnia in adults. Fourteen healthy adults (24 ± 2 yr) participated in three experimental visits sitting for 2.5 h in a mild hypercapnic environment (CO2 = 1,500 ppm): control (CON, no limb movement), passive lower limb movement (PASS), and active lower limb movement (ACT) during sitting. At all visits, brachial and popliteal artery flow-mediated dilation (FMD), microvascular function, plasmatic levels of nitrate/nitrite and endothelin-1, and heart rate variability were assessed before and after sitting. Brachial and popliteal artery FMDs were reduced in CON and PASS (P < 0.05) but were preserved (P > 0.05) in ACT. Microvascular function was blunted in CON (P < 0.05) but was preserved in PASS and ACT (P > 0.05). In addition, total plasma nitrate/nitrite was preserved in ACT (P > 0.05) but was reduced in CON and PASS (P < 0.05), and endothelin-1 levels were decreased in ACT (P < 0.05). Both passive and active movement induced a greater ratio between the low-frequency and high-frequency bands for heart rate variability (P < 0.05). For the first time, to our knowledge, we found that brief periods of passive leg movement can preserve microvascular function, but that an intervention that elicits larger increases in shear rate, such as low-intensity exercise, is required to fully protect both macrovascular and microvascular function and circulating vasoactive substance balance.NEW & NOTEWORTHY Passive leg movement could not preserve macrovascular endothelial function, whereas active leg movement could protect endothelial function. Attenuated microvascular function can be salvaged by passive movement and active movement. Preservation of macrovascular hemodynamics and plasma total nitrate/nitrite and endothelin-1 during prolonged sitting requires active movement. These findings dissociate the impacts induced by mechanical stress (passive movement) from the change in metabolism (active movement) on the vasculature during prolonged sitting in a mild hypercapnic environment.
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Hipercapnia , Perna (Membro) , Adulto , Artéria Braquial , Endotélio Vascular/fisiologia , Humanos , Extremidade Inferior/irrigação sanguínea , Fluxo Sanguíneo Regional/fisiologia , Vasodilatação/fisiologiaRESUMO
Diacylglycerol kinase (DGK), a lipid kinase, catalyzes the conversion of diacylglycerol (DAG) to phosphatidic acid, thereby terminating DAG-mediated signaling by Gq-coupled receptors that regulate contraction of airway smooth muscle (ASM). A previous study from our laboratory demonstrated that DGK inhibition or genetic ablation leads to reduced ASM contraction and provides protection for allergen-induced airway hyperresponsiveness. However, the mechanism by which DGK regulates contractile signaling in ASM is not well established. Herein, we investigated the role of prorelaxant cAMP-protein kinase A (PKA) signaling in DGK-mediated regulation of ASM contraction. Pretreatment of human ASM cells with DGK inhibitor I activated PKA as demonstrated by the phosphorylation of PKA substrates, VASP, Hsp20, and CREB, which was abrogated when PKA was inhibited pharmacologically or molecularly using overexpression of the PKA inhibitor peptide, PKI. Furthermore, inhibition of DGK resulted in induction of cyclooxygenase (COX) and generation of prostaglandin E2 (PGE2 ) with concomitant activation of Gs-cAMP-PKA signaling in ASM cells in an autocrine/paracrine fashion. Inhibition of protein kinase C (PKC) or extracellular-signal-regulated kinase (ERK) attenuated DGK-mediated production of PGE2 and activation of cAMP-PKA signaling in human ASM cells, suggesting that inhibition of DGK activates the COX-PGE2 pathway in a PKC-ERK-dependent manner. Finally, DGK inhibition-mediated attenuation of contractile agonist-induced phosphorylation of myosin light chain 20 (MLC-20), a marker of ASM contraction, involves COX-mediated cAMP production and PKA activation in ASM cells. Collectively these findings establish a novel mechanism by which DGK regulates ASM contraction and further advances DGK as a potential therapeutic target to provide effective bronchoprotection in asthma.
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Proteínas Quinases Dependentes de AMP Cíclico , Diacilglicerol Quinase , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Diacilglicerol Quinase/genética , Dinoprostona/farmacologia , Humanos , Contração Muscular , Proteína Quinase CRESUMO
Exaggerated airway smooth muscle (ASM) contraction regulated by the Gq family of G protein-coupled receptors causes airway hyperresponsiveness in asthma. Activation of Gq-coupled G protein-coupled receptors leads to phospholipase C (PLC)-mediated generation of inositol triphosphate (IP3) and diacylglycerol (DAG). DAG signaling is terminated by the action of DAG kinase (DGK) that converts DAG into phosphatidic acid (PA). Our previous study demonstrated that DGKζ and α isoform knockout mice are protected from the development of allergen-induced airway hyperresponsiveness. Here we aimed to determine the mechanism by which DGK regulates ASM contraction. Activity of DGK isoforms was inhibited in human ASM cells by siRNA-mediated knockdown of DGKα and ζ, whereas pharmacological inhibition was achieved by pan DGK inhibitor I (R59022). Effects of DGK inhibition on contractile agonist-induced activation of PLC and myosin light chain (MLC) kinase, elevation of IP3, and calcium levels were assessed. Furthermore, we used precision-cut human lung slices and assessed the role of DGK in agonist-induced bronchoconstriction. DGK inhibitor I attenuated histamine- and methacholine-induced bronchoconstriction. DGKα and ζ knockdown or pretreatment with DGK inhibitor I resulted in attenuated agonist-induced phosphorylation of MLC and MLC phosphatase in ASM cells. Furthermore, DGK inhibition decreased Gq agonist-induced calcium elevation and generation of IP3 and increased histamine-induced production of PA. Finally, DGK inhibition or treatment with DAG analog resulted in attenuation of activation of PLC in human ASM cells. Our findings suggest that DGK inhibition perturbed the DAG:PA ratio, resulting in inhibition of Gq-PLC activation in a negative feedback manner, resulting in protection against ASM contraction.
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Broncoconstrição/efeitos dos fármacos , Diacilglicerol Quinase/antagonistas & inibidores , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Contração Muscular/efeitos dos fármacos , Músculo Liso/enzimologia , Pirimidinonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Tiazóis/farmacologia , Broncoconstrição/genética , Células Cultivadas , Diacilglicerol Quinase/genética , Diacilglicerol Quinase/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Técnicas de Silenciamento de Genes , Humanos , Contração Muscular/genética , Transdução de Sinais/genéticaRESUMO
Attention-deficit hyperactivity disorder (ADHD) is a neurological and neurodevelopmental childhood-onset disorder characterized by a persistent pattern of inattentiveness, impulsiveness, restlessness, and hyperactivity. These symptoms may continue in 55-66% of cases from childhood into adulthood. Even though the precise etiology of ADHD is not fully understood, it is considered as a multifactorial and heterogeneous disorder with several contributing factors such as heritability, auxiliary to neurodevelopmental issues, severe brain injuries, neuroinflammation, consanguineous marriages, premature birth, and exposure to environmental toxins. Neuroimaging and neurodevelopmental assessments may help to explore the possible role of genetic variations on ADHD neuropsychobiology. Multiple genetic studies have observed a strong genetic association with various aspects of neuropsychobiological functions, including neural abnormalities and delayed neurodevelopment in ADHD. The advancement in neuroimaging and molecular genomics offers the opportunity to analyze the impact of genetic variations alongside its dysregulated pathways on structural and functional derived brain imaging phenotypes in various neurological and psychiatric disorders, including ADHD. Recently, neuroimaging genomic studies observed a significant association of brain imaging phenotypes with genetic susceptibility in ADHD. Integrating the neuroimaging-derived phenotypes with genomics deciphers various neurobiological pathways that can be leveraged for the development of novel clinical biomarkers, new treatment modalities as well as therapeutic interventions for ADHD patients. In this review, we discuss the neurobiology of ADHD with particular emphasis on structural and functional changes in the ADHD brain and their interactions with complex genomic variations utilizing imaging genetics methodologies. We also highlight the genetic variants supposedly allied with the development of ADHD and how these, in turn, may affect the brain circuit function and related behaviors. In addition to reviewing imaging genetic studies, we also examine the need for complementary approaches at various levels of biological complexity and emphasize the importance of combining and integrating results to explore biological pathways involved in ADHD disorder. These approaches include animal models, computational biology, bioinformatics analyses, and multimodal imaging genetics studies.
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Transtorno do Deficit de Atenção com Hiperatividade , Adulto , Animais , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/genética , Encéfalo/diagnóstico por imagem , Criança , Predisposição Genética para Doença , Variação Genética , Humanos , NeuroimagemRESUMO
Peripheral artery disease (PAD) is characterized by the accumulation of atherosclerotic plaques in the lower extremity conduit arteries, which impairs blood flow and walking capacity. Dietary nitrate has been used to reduce blood pressure (BP) and improve walking capacity in PAD. However, a standardized dose for PAD has not been determined. Therefore, we sought to determine the effects of a body mass-normalized moderate dose of nitrate (0.11 mmol nitrate/kg) as beetroot juice on serum nitrate/nitrite, vascular function, walking capacity, and tissue oxygen utilization capacity in patients with PAD. A total of 11 patients with PAD received either nitrate supplement or placebo in a randomized crossover design. Total serum nitrate/nitrite, resting BP, brachial and popliteal artery endothelial function (flow-mediated dilation, FMD), arterial stiffness (pulse-wave velocity, PWV), augmentation index (AIx), maximal walking distance and time, claudication onset time, and skeletal muscle oxygen utilization were measured pre- and postnitrate and placebo intake. There were significant group × time interactions (P < 0.05) for serum nitrate/nitrite, FMD, BP, walking distance and time, and skeletal muscle oxygen utilization. The nitrate group showed significantly increased serum nitrate/nitrite (Δ1.32 µM), increased brachial and popliteal FMD (Δ1.3% and Δ1.7%, respectively), reduced peripheral and central systolic BP (Δ-4.7 mmHg and Δ-8.2 mmHg, respectively), increased maximal walking distance (Δ92.7 m) and time (Δ56.3 s), and reduced deoxygenated hemoglobin during walking. There were no changes in PWV, AIx, or claudication (P > 0.05). These results indicate that a body-mass normalized moderate dose of nitrate may be effective and safe for reducing BP, improving endothelial function, and improving walking capacity in patients with PAD.
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Beta vulgaris , Endotélio Vascular/fisiopatologia , Tolerância ao Exercício , Sucos de Frutas e Vegetais , Claudicação Intermitente/dietoterapia , Nitratos/administração & dosagem , Doença Arterial Periférica/dietoterapia , Caminhada , Idoso , Pressão Sanguínea , Índice de Massa Corporal , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Claudicação Intermitente/diagnóstico , Claudicação Intermitente/fisiopatologia , Masculino , Pessoa de Meia-Idade , Nebraska , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/fisiopatologia , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento , Rigidez Vascular , VasodilataçãoRESUMO
Infections due to extended-spectrum ß-lactamase- (ESBL-) producing Gram-negative bacteria have led to increased mortality, morbidity, and economic burden worldwide. These bacteria can colonize the healthy intestine of human beings and can disseminate in communities and hospital. This study aimed to investigate the prevalence of fecal carriage of ESBL-producing Escherichia coli and Klebsiella species among health science (HS) and non-health science (NHS) students. This descriptive cross-sectional study was conducted on 104 HS and 104 NHS students in which one stool sample from each student was collected and processed for bacterial culture and sensitivity testing according to standard bacteriological procedures. Each morphotype was identified and characterized phenotypically. The antimicrobial sensitivity profile of bacterial isolates was determined by the Kirby-Bauer disk diffusion technique. ESBL production was tested by combination disk method as recommended by the Clinical and Laboratory Standards Institute. Out of 208 stool samples, E. coli and Klebsiella spp. were recovered from 203 (86.8%) and 31 (13.2%) stool samples, respectively. Among those 234 isolates, 69 were positive for ESBL which included E. coli (n = 66, 95.7%) and Klebsiella spp. (n = 3, 4.3%). Fifty (42.4%) out of 118 isolates from HS students and 19 (16.4%) out of 116 from NHS students were colonized by ESBL-producers. Compared to non-ESBL producers, a higher number of ESBL-producing isolates were resistant to ciprofloxacin (14.5% vs. 1.8%, p < 0.001), cotrimoxazole (59.4% vs. 16.4%, p < 0.001), and amikacin (10.1% vs 4.2%, p < 0.001). All E. coli and Klebsiella species isolates were susceptible to meropenem. The prevalence of fecal carriage of ESBL-producing bacteria was higher in HS students; however, there was a considerable number of these strains colonizing NHS students as well. This "iceberg phenomenon" of asymptomatic carriage of ESBL-producing pathogens might act as a source of infection in both the community and hospitals. Therefore, surveillance of carriage of drug-resistant bacteria should be performed regularly.
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BACKGROUND: To evaluate the social and academic impact of adolescents with Attention Deficit Hyperactivity Disorder (ADHD) and gender differences compared with their non-ADHD peers. METHODS: A cross-sectional descriptive study using a standardized rating scale of teacher observations was conducted in the schools of Qatar from 7th to 12th grades. Teachers completed Swanson, Nolan, and Pelham (SNAP-IV) rating scale questionnaires for the ADHD core symptoms together with nine questions to evaluate the academic and social difficulties in all participants. RESULTS: A total of 1775 students (mean age: 15 ± 1.5 years; boys/girls: 717/1058) were included in this study. Based on the SNAP-IV rating scale, 150 students were showing core symptoms of ADHD and classified as having ADHD (8.5%; boys/girls; 93/57) and 1625 students as non-ADHD peers (91.5%; boys/girls; 624/1001). Prevalence of ADHD among adolescent students is 8.5%, and it varied significantly between genders with 13% of boys and 5.4% of girls affected by this disorder. Adolescents with ADHD had more academic and social difficulties than their non-ADHD peers, the boys more so than the girls. Boys with inattentive subtype of ADHD had more academic difficulties than girls, while girls had more social difficulties than boys. CONCLUSION: The results of this study revealed that ADHD among adolescents is substantially associated with academic and social difficulties in the school environment. Gender differences among students with ADHD should be considered in the school and clinical environment.
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Diabetes mellitus (DM) is caused either due to insulin deficiency (T1DM) or insulin resistance (T2DM). DM increases the risk of heart failure by diabetic cardiomyopathy (DMCM), a cardiac muscle disorder that leads to a progressive decline in diastolic function, and ultimately systolic dysfunction. Mouse models of T1DM and T2DM exhibit clinical signs of DMCM. Growing evidence implicates microRNA (miRNA), an endogenous, non-coding, regulatory RNA, in the pathogenesis and signaling of DMCM. Therefore, inhibiting deleterious miRNAs and mimicking cardioprotective miRNAs could provide a potential therapeutic intervention for DMCM. miRNA-133a (miR-133a) is a highly abundant miRNA in the human heart. It is a cardioprotective miRNA, which is downregulated in the DM heart. It has anti-hypertrophic and anti-fibrotic effects. miR-133a mimic treatment after the onset of early DMCM can reverse histological and clinical signs of the disease in mice. We hypothesized that overexpression of cardiac-specific miR-133a in Ins2+/- Akita (T1DM) mice can prevent progression of DMCM. Here, we describe a method to create and validate cardiac-specific Ins2+/-/miR-133aTg mice to determine whether cardiac-specific miR-133a overexpression prevents development of DMCM. These strategies demonstrate the value of genetic modeling of human disease such as DMCM and evaluate the potential of miRNA as a therapeutic intervention.
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Diabetes Mellitus Experimental/metabolismo , Coração/fisiopatologia , Insulina/genética , MicroRNAs/genética , Animais , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Regulação para Baixo/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/patologia , Miócitos Cardíacos/patologiaRESUMO
Bone density disorders are characterized by a reduction in bone mass density and strength, which lead to an increase in the susceptibility to sudden and unexpected fractures. Despite the serious consequences of low bone mineral density (BMD) and its significant impact on human health, most affected individuals may not know that they have the disease because it is asymptomatic. Therefore, understanding the genetic basis of low BMD and osteoporosis is essential to fully elucidate its pathobiology and devise preventative or therapeutic approaches. Here we sequenced the whole genomes of 3000 individuals from the Qatar Biobank and conducted genome-wide association analyses to identify genetic risk factors associated with low BMD in the Qatari population. Fifteen variants were significantly associated with total body BMD (p < 5 × 10-8). Of these, five variants had previously been reported by and were directionally consistent with previous genome-wide association study data. Ten variants were new: six intronic variants located at six gene loci (MALAT1/TALAM1, FASLG, LSAMP, SAG, FAM189A2, and LOC101928063) and four intergenic variants. This first such study in Qatar provides a new insight into the genetic architecture of low BMD in the Qatari population. Nevertheless, more studies are needed to validate these findings and to elucidate the functional effects of these variants on low BMD and bone fracture susceptibility.
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Epigenetic reprogramming and autophagy have critical roles in differentiation of stem cells. However, very little is known about how epigenetic modifications are mediated and how they contribute to autophagy and differentiation in human cardiac stem cells (hCSCs). Previously, we have reported that intracellular matrix metalloproteinase-9 (MMP9), a collagenase, mediates cell death in hCSCs. Here, we investigated whether intracellular MMP9 mediates epigenetic modifications and autophagy in hCSCs. We created MMP9KO hCSCs and treated them with 5-azacytidine, an inhibitor of DNA methylation, and bafilomycin A1, an inhibitor of autophagosome degradation, and evaluated epigenetic modifications, autophagic flux, and differentiation. Our results showed compromised epigenetic modifications, reduced autophagy, and impaired differentiation in MMP9KO hCSCs. Remarkably, paracrine MMP9 supplementation restored epigenetic modifications but further reduced autophagy in MMP9KO hCSCs. We conclude that intracellular MMP9 is a critical mediator of epigenetic modifications and autophagy in hCSCs. Furthermore, the endocrine and paracrine effects of MMP9 vary for regulating autophagy in hCSCs. These novel roles of MMP9 are valuable for stem cell therapy.
Assuntos
Autofagia/genética , Epigênese Genética , Metaloproteinase 9 da Matriz/genética , Miócitos Cardíacos/metabolismo , Células-Tronco/metabolismo , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Autofagia/efeitos dos fármacos , Azacitidina/farmacologia , Sistemas CRISPR-Cas , Diferenciação Celular/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA/efeitos dos fármacos , DNA Metiltransferase 3A/genética , DNA Metiltransferase 3A/metabolismo , Deleção de Genes , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Macrolídeos/farmacologia , Metaloproteinase 9 da Matriz/deficiência , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Comunicação Parácrina/efeitos dos fármacos , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacosRESUMO
Curcumae Rhizoma, also known as Ezhu is a traditional Chinese medicine that has been used for many centuries against several diseases. The rhizome of the plant is composed of curcuminoids (curcumin, demethoxycurcumin, and bisdemethoxycurcumin), and essential volatile oils including curcumol, curdione, and germacrone. While curcuminoids have been extensively studied for their antimicrobial, antioxidant, anti-inflammatory and anticancer properties, the therapeutic efficacy of curcumol is still emerging. Recent studies have shown anticancer properties of curcumol against multiple solid tumors such as breast, colorectal, head and neck, and lung adenocarcinomas. The underlying anti-tumor mechanisms revealed inhibition of several signaling pathways (NF-κB, MAPK, PI-3K/AKT, and GSK-3ß) associated with cell proliferation, survival, anti-apoptosis, invasion and metastasis. Besides curcumol, extracts from the Curcumae Rhizoma roots possess many other terpenoids such as ß-elemene, δ-elemene, germacrone, furanodiene and furanodienone with known anticancer properties. In this review, we comprehensively focused on the composition of Curcumae Rhizoma essential oils, their structure, isolation and therapeutic uses of curcumol to aid in the improvement and development of novel drugs with minimal cytotoxicity, enhanced efficacy, and less cost.
Assuntos
Óleos Voláteis , Sesquiterpenos , Quinase 3 da Glicogênio Sintase , Humanos , Óleos Voláteis/farmacologia , Rizoma , Sesquiterpenos/farmacologia , TerpenosRESUMO
Anthocyanins and bromelain have gained significant attention due to their antioxidative and anti-inflammatory properties. Both have been shown to improve endothelial function, blood pressure (BP) and oxygen utility capacity in humans; however, the combination of these two and the impacts on endothelial function, BP, total antioxidant capacity (TAC) and oxygen utility capacity have not been previously investigated. The purpose of this study was to investigate the impacts of a combined anthocyanins and bromelain supplement (BE) on endothelial function, BP, TAC, oxygen utility capacity and fatigability in healthy adults. Healthy adults (n 18, age 24 (sd 4) years) received BE or placebo in a randomised crossover design. Brachial artery flow-mediated dilation (FMD), BP, TAC, resting heart rate, oxygen utility capacity and fatigability were measured pre- and post-BE and placebo intake. The BE group showed significantly increased FMD, reduced systolic BP and improved oxygen utility capacity compared with the placebo group (P < 0·05). Tissue saturation and oxygenated Hb significantly increased following BE intake, while deoxygenated Hb significantly decreased (P < 0·05) during exercise. Additionally, TAC was significantly increased following BE intake (P < 0·05). There were no significant differences for resting heart rate, diastolic BP or fatigability index. These results suggest that BE intake is an effective nutritional therapy for improving endothelial function, BP, TAC and oxygen utility capacity, which may be beneficial to support vascular health in humans.