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1.
J Neuroinflammation ; 21(1): 107, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659061

RESUMO

Neuroinflammation and synaptodendritic damage represent the pathological hallmarks of HIV-1 associated cognitive disorders (HAND). The post-synaptic protein neurogranin (Nrgn) is significantly reduced in the frontal cortex of postmortem brains from people with HIV (PWH) and it is associated with inflammatory factors released by infected microglia/macrophages. However, the mechanism involved in synaptic loss have yet to be elucidated. In this study, we characterized a newly identified long non-coding RNA (lncRNA) transcript (RP11-677M14.2), which is antisense to the NRGN locus and is highly expressed in the frontal cortex of HIV-1 individuals. Further analysis indicates an inverse correlation between the expression of RP11-677M14.2 RNA and Nrgn mRNA. Additionally, the Nrgn-lncRNA axis is dysregulated in neurons exposed to HIV-1 infected microglia conditioned medium enriched with IL-1ß. Moreover, in vitro overexpression of this lncRNA impacts Nrgn expression at both mRNA and protein levels. Finally, we modeled the Nrgn-lncRNA dysregulation within an HIV-1-induced inflammatory environment using brain organoids, thereby corroborating our in vivo and in vitro findings. Together, our study implicates a plausible role for lncRNA RP11-677M14.2 in modulating Nrgn expression that might serve as the mechanistic link between Nrgn loss and cognitive dysfunction in HAND, thus shedding new light on the mechanisms underlying synaptodendritic damage.


Assuntos
HIV-1 , Neurogranina , Doenças Neuroinflamatórias , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/metabolismo , RNA Longo não Codificante/genética , Neurogranina/metabolismo , Neurogranina/genética , Doenças Neuroinflamatórias/metabolismo , Infecções por HIV/metabolismo , Infecções por HIV/genética , Infecções por HIV/patologia , Microglia/metabolismo , Masculino , Animais
2.
Phys Rev Lett ; 132(15): 151902, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682992

RESUMO

We present the first determination of the energy dependence of the B-D[over ¯] and B^{*}-D[over ¯] isospin-0, S-wave scattering amplitudes both below and above the thresholds using lattice QCD, which allows us to investigate rigorously whether mixed bottom-charm b[over ¯]c[over ¯]ud tetraquarks exist as bound states or resonances. The scattering phase shifts are obtained using Lüscher's method from the energy spectra in two different volumes. To ensure that no relevant energy level is missed, we use large, symmetric 7×7 and 8×8 correlation matrices that include, at both source and sink, B^{(*)}-D[over ¯] scattering operators with the lowest three or four possible back-to-back momenta in addition to local b[over ¯]c[over ¯]ud operators. We fit the energy dependence of the extracted scattering phase shifts using effective-range expansions. We observe sharp peaks in the B^{(*)}-D[over ¯] scattering rates close to the thresholds, which are associated with shallow bound states, either genuine or virtual, a few MeV or less below the B^{(*)}-D[over ¯] thresholds. In addition, we find hints for resonances with masses of order 100 MeV above the thresholds and decay widths of order 200 MeV.

3.
Chemistry ; : e202401833, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819585

RESUMO

Ionic detergents enable applications and cause harm in biospheres due to cell toxicity. The utility of covalent combinations between ionic and non-ionic detergent headgroups in modulating cell toxicity remains speculative due to the yet rarely explored synthesis. We close this gap and establish the modular synthesis of ionic/non-ionic hybrid detergents. We restructure a combinatorial methallyl dichloride one-pot coupling into a two-step coupling, which reduces by-products, improves product yields, and enables the gram-scale preparation of asymmetric, cationic/non-ionic and anionic/non-ionic hybrid detergents. Our modular synthesis delivers new modalities for the design of ionic detergents, including an unprecedented scaling of properties that determine applications, such as charge, critical micelle concentration (cmc), solubilizing properties, hard water tolerance, and cell compatibility. We uncover that shielding the charge in ionic headgroups can switch the detergent species that is toxic to cells from monomers to mixtures of monomers and micellar assemblies. Establishing the chemistry of ionic/non-ionic hybrid detergents provides a missing evolutionary link in the structural comparison of ionic and non-ionic detergents, enables an easy synthesis access to yet unexplored chemical spaces of asymmetric hybrid materials, and delivers new modalities for designing the toxicity of supramolecular nanomaterials.

4.
Cell Mol Life Sci ; 80(2): 54, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36715759

RESUMO

Neural stem cells reside in the subgranular zone, a specialized neurogenic niche of the hippocampus. Throughout adulthood, these cells give rise to neurons in the dentate gyrus, playing an important role in learning and memory. Given that these core cognitive processes are disrupted in numerous disease states, understanding the underlying mechanisms of neural stem cell proliferation in the subgranular zone is of direct practical interest. Here, we report that mature neurons, neural stem cells and neural precursor cells each secrete the neurovascular protein epidermal growth factor-like protein 7 (EGFL7) to shape this hippocampal niche. We further demonstrate that EGFL7 knock-out in a Nestin-CreERT2-based mouse model produces a pronounced upregulation of neurogenesis within the subgranular zone. RNA sequencing identified that the increased expression of the cytokine VEGF-D correlates significantly with the ablation of EGFL7. We substantiate this finding with intraventricular infusion of VEGF-D upregulating neurogenesis in vivo and further show that VEGF-D knock-out produces a downregulation of neurogenesis. Finally, behavioral studies in EGFL7 knock-out mice demonstrate greater maintenance of spatial memory and improved memory consolidation in the hippocampus by modulation of pattern separation. Taken together, our findings demonstrate that both EGFL7 and VEGF-D affect neurogenesis in the adult hippocampus, with the ablation of EGFL7 upregulating neurogenesis, increasing spatial learning and memory, and correlating with increased VEGF-D expression.


Assuntos
Células-Tronco Neurais , Camundongos , Animais , Células-Tronco Neurais/metabolismo , Aprendizagem Espacial , Fator D de Crescimento do Endotélio Vascular/metabolismo , Proliferação de Células/fisiologia , Hipocampo/metabolismo , Neurogênese/genética , Camundongos Knockout , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
5.
BMC Neurol ; 19(1): 304, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783737

RESUMO

BACKGROUND: Paraneoplastic limbic encephalitis (PLE) is a rare autoimmune neurological syndrome observed in cancer patients. PLE is difficult to diagnose and presents a variable response to treatment, depending on the characteristics of the tumor and neuronal autoantibodies. CASE PRESENTATION: A 64-year-old, Caucasian, non-smoker man presented with a rapidly developing cognitive impairment, personality change, spatial disorientation, and short-term memory loss associated with anorexia and cervical and inguinal lymph nodes. The 18F-FDG PET scan documented intensely hypermetabolic lymph nodes, which histologically corresponded to a metastasis from a small cell neuroendocrine carcinoma. The brain MRI revealed a high T2-weighted FLAIR signal of the hippocamps, consisted with a PLE. The presence of anti-neuronal Hu antibodies confirmed the diagnosis. The patient underwent plasmapheresis, associated to a systemic chemotherapy resulting in a partial and temporary improvement of the neurological symptoms. Four cycles of intravenous immunoglobulins were also necessary. After six cures of chemotherapy, the lymph node metastases regressed. However, a new anorectal lesion was detected and was histologically confirmed as a primary small cell neuroendocrine carcinoma, which was treated with concomitant chemoradiotherapy. At the end of this treatment, the patient showed a rapid tumor progression leading to his death. CONCLUSIONS: This case highlights the rare entity, PLE, which is difficult to diagnose and manage. In addition, this is the first published case of PLE associated with an anorectal small cell neuroendocrine carcinoma, which appeared after completion of systemic chemotherapy.


Assuntos
Carcinoma Neuroendócrino/diagnóstico , Carcinoma de Células Pequenas/diagnóstico , Encefalite Límbica/diagnóstico , Autoanticorpos , Fluordesoxiglucose F18 , Hipocampo/patologia , Humanos , Encefalite Límbica/imunologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons
7.
J Neuroinflammation ; 15(1): 126, 2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-29703241

RESUMO

BACKGROUND: Human immunodeficiency virus type 1 (HIV-1)-associated neurocognitive disorder (HAND) is a common outcome of a majority of HIV-1-infected subjects and is associated with synaptodendritic damage. Neurogranin (Ng), a postsynaptic protein, and calmodulin (CaM) are two important players of synaptic integrity/functions. The biological role of Ng in the context of HAND is unknown. METHODS: We compared the expression of Ng in frontal cortex (FC) tissues from control and HIV-1-positive subjects with and without HAND by immunohistochemistry, western blot, and qRT-PCR. The interaction between Ng and CaM was analyzed by co-immunoprecipitation. Ng, microtubule-associated protein 2 (MAP2), CaM, CaM-dependent protein kinase II (CaMKII), CREB, synaptophysin (Syp), and synapsin I (Syn I) expressions were evaluated by western blot using FC tissue lysates and differentiated SH-SY5Y (dSH-SY5Y) cells. Identification of inflammatory factors related to Ng loss was accomplished by exposing dSH-SY5Y cells to HIV-1 and mock-infected monocyte-derived macrophage (MDM) supernatants or HIV-1 NLYU2 pseudotyped with VSV-G-Env. Levels of interleukin (IL)-1ß, IL-8, tumor necrosis factor (TNF)-α, monocyte chemoattractant protein (MCP)-1, MCP-2, and CXCL5 in MDM supernatants were measured by ELISA. Association of IL-1ß and IL-8 to Ng expression in context of HIV-1 infection was evaluated in the presence or absence of neutralizing antibodies against these cytokines. RESULTS: Expression level of Ng was reduced significantly in FC of HAND-positive (HAND+) patients compared to uninfected individuals. Although no difference was found in CaM expression, interaction between Ng and CaM was reduced in HAND+ patients, which was associated with decreased level of CaMKII, a downstream signaling molecule of CaM pathway. This in turn resulted in reduction of synaptic markers, Syp and Syn I. HIV-1 infection directly had no considerable effect on dysregulation of Ng expression in dSH-SY5Y cells, whereas high amount of pro-inflammatory IL-1ß and IL-8 in HIV-1-infected MDM supernatants was associated with significant reduction in Ng expression. CONCLUSIONS: Synaptic damage in HAND+ patients could be a result of abrogation of Ng through HIV-1-induced inflammation that dysregulates Ng-CaM interaction and downstream signaling cascades associated with synaptodendritic functions. This is the first study evaluating the potential role of Ng in the context of HIV-1 neuropathogenesis.


Assuntos
Complexo AIDS Demência/metabolismo , Dendritos/metabolismo , Lobo Frontal/metabolismo , HIV-1 , Neurogranina/biossíntese , Sinapses/metabolismo , Complexo AIDS Demência/patologia , Adulto , Idoso , Dendritos/patologia , Feminino , Lobo Frontal/patologia , Humanos , Inflamação/metabolismo , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Sinapses/patologia
9.
Chempluschem ; 89(1): e202300386, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37668309

RESUMO

Detergents are amphiphilic molecules that serve as enabling steps for today's world applications. The increasing diversity of the detergentome is key to applications enabled by detergent science. Regardless of the application, the optimal design of detergents is determined empirically, which leads to failed preparations, and raising costs. To facilitate project planning, here we review synthesis strategies that drive the diversification of the detergentome. Synthesis strategies relevant for industrial and academic applications include linear, modular, combinatorial, bio-based, and metric-assisted detergent synthesis. Scopes and limitations of individual synthesis strategies in context with industrial product development and academic research are discussed. Furthermore, when designing detergents, the selection of molecular building blocks, i. e., head, linker, tail, is as important as the employed synthesis strategy. To facilitate the design of safe-to-use and tailor-made detergents, we provide an overview of established head, linker, and tail groups and highlight selected scopes and limitations for applications. It becomes apparent that most recent contributions to the increasing chemical diversity of detergent building blocks originate from the development of detergents for membrane protein studies. The overview of synthesis strategies and molecular blocks will bring us closer to the ability to predictably design and synthesize optimal detergents for challenging future applications.


Assuntos
Detergentes , Proteínas de Membrana , Detergentes/química , Proteínas de Membrana/química
10.
Res Sq ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38260270

RESUMO

Neuroinflammation and synaptodendritic damage represent the pathological hallmarks of HIV-1 associated cognitive disorders (HAND). The post-synaptic protein neurogranin (Nrgn) is significantly reduced in the frontal cortex of postmortem brains from people with HIV (PWH) and it is associated with inflammatory factors released by infected microglia/macrophages. However, the mechanism involved in synaptic loss have yet to be elucidated. In this study, we characterized a newly identified long non-coding RNA (lncRNA) transcript (RP11-677M14.2), which is antisense to the NRGN locus and is highly expressed in the frontal cortex of HIV-1 individuals. Further analysis indicates an inverse correlation between the expression of RP11-677M14.2 RNA and Nrgn mRNA. Additionally, the Nrgn-lncRNA axis is dysregulated in neurons exposed to HIV-1 infected microglia conditioned medium enriched with IL-1b. Moreover, in vitro overexpression of this lncRNA impact Nrgn expression at both mRNA and protein levels. Finally, we modeled the Nrgn-lncRNA dysregulation within an HIV-1-induced neuroinflammatory environment using brain organoids, thereby corroborating our in vivo and in vitro findings. Together, our study implicates a plausible role for lncRNA RP11-677M14.2 in modulating Nrgn expression that might serve as the mechanistic link between Nrgn loss and cognitive dysfunction in HAND, thus shedding new light on the mechanisms underlying synaptodendritic damage.

11.
Methods Mol Biol ; 2807: 261-270, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38743234

RESUMO

The development of 3D-organoid models has revolutionized the way diseases are studied. Recently, our brain organoid model has been shown to recapitulate in in vitro the human brain cytoarchitecture originally encountered in HIV-1 neuropathogenesis, allowing downstream applications. Infected monocytes, macrophages, and microglia are critically important immune cells for infection and dissemination of HIV-1 throughout brain during acute and chronic phase of the disease. Once in the brain parenchyma, long-lived infected monocytes/macrophages along with resident microglia contribute to the establishment of CNS latency in people with HIV (PWH). Hence, it is important to better understand how HIV-1 enters and establishes infection and latency in CNS to further develop cure strategies. Here we detailed an accessible protocol to incorporate monocytes (infected and/or labeled) as a model of transmigration of peripheral monocytes into brain organoids that can be applied to characterize HIV-1 neuroinvasion and virus dissemination.


Assuntos
Encéfalo , Infecções por HIV , HIV-1 , Monócitos , Organoides , Organoides/virologia , Organoides/patologia , Humanos , HIV-1/fisiologia , HIV-1/patogenicidade , Monócitos/virologia , Monócitos/imunologia , Infecções por HIV/virologia , Infecções por HIV/imunologia , Infecções por HIV/patologia , Encéfalo/virologia , Encéfalo/patologia , Encéfalo/imunologia , Microglia/virologia , Microglia/imunologia , Microglia/patologia , Macrófagos/virologia , Macrófagos/imunologia , Latência Viral
12.
Cells ; 12(9)2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37174713

RESUMO

Elongation of the posterior body axis is distinct from that of the anterior trunk and head. Early drivers of posterior elongation are the neural plate/tube and notochord, later followed by the presomitic mesoderm (PSM), together with the neural tube and notochord. In axolotl, posterior neural plate-derived PSM is pushed posteriorly by convergence and extension of the neural plate. The PSM does not go through the blastopore but turns anteriorly to join the gastrulated paraxial mesoderm. To gain a deeper understanding of the process of axial elongation, a detailed characterization of PSM morphogenesis, which precedes somite formation, and of other tissues (such as the epidermis, lateral plate mesoderm and endoderm) is needed. We investigated these issues with specific tissue labelling techniques (DiI injections and GFP+ tissue grafting) in combination with optical tissue clearing and 3D reconstructions. We defined a spatiotemporal order of PSM morphogenesis that is characterized by changes in collective cell behaviour. The PSM forms a cohesive tissue strand and largely retains this cohesiveness even after epidermis removal. We show that during embryogenesis, the PSM, as well as the lateral plate and endoderm move anteriorly, while the net movement of the axis is posterior.


Assuntos
Mesoderma , Placa Neural , Mesoderma/fisiologia , Morfogênese , Desenvolvimento Embrionário , Músculos
13.
J Acquir Immune Defic Syndr ; 88(5): 426-438, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34757972

RESUMO

OBJECTIVES: This study describes prevention behavior and psychosocial health among people living with HIV (PLHIV) and HIV-negative people during the early wave of the coronavirus disease 2019 (COVID-19) pandemic in the United States. We assessed differences by HIV status and associations between social disruption and psychosocial health. DESIGN: A cross-sectional telephone/videoconference administered survey of 3411 PLHIV and HIV-negative participants in the Multicenter AIDS Cohort Study/WIHS Combined Cohort Study (MWCCS). METHODS: An instrument combining new and validated measures was developed to assess COVID-19 prevention efforts, social disruptions (loss of employment, childcare, health insurance, and financial supports), experiences of abuse, and psychosocial health. Interviews were performed between April and June 2020. Associations between social disruptions and psychosocial health were explored using multivariable logistic regression, adjusting for sociodemographics and HIV status. RESULTS: Almost all (97.4%) participants reported COVID-19 prevention behavior; 40.1% participants reported social disruptions, and 34.3% reported health care appointment disruption. Men living with HIV were more likely than HIV-negative men to experience social disruptions (40.6% vs. 32.9%; P < 0.01), whereas HIV-negative women were more likely than women with HIV to experience social disruptions (51.1% vs. 39.8%, P < 0.001). Participants who experienced ≥2 social disruptions had significantly higher odds of depression symptoms [aOR = 1.32; 95% confidence interval (CI): 1.12 to 1.56], anxiety (aOR = 1.63; 95% CI: 1.17 to 2.27), and social support dissatisfaction (aOR = 1.81; 95% CI: 1.26 to 2.60). CONCLUSIONS: This study builds on emerging literature demonstrating the psychosocial health impact related to the COVID-19 pandemic by providing context specific to PLHIV. The ongoing pandemic requires structural and social interventions to decrease social disruption and address psychosocial health needs among the most vulnerable populations.


Assuntos
COVID-19/epidemiologia , Soronegatividade para HIV , Soropositividade para HIV/epidemiologia , Soropositividade para HIV/psicologia , Saúde Mental/estatística & dados numéricos , COVID-19/psicologia , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Prevalência , Estados Unidos/epidemiologia
14.
Front Plant Sci ; 11: 176, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256504

RESUMO

DNA methylation is involved in many different biological processes in the development and well-being of crop plants such as transposon activation, heterosis, environment-dependent transcriptome plasticity, aging, and many diseases. Whole-genome bisulfite sequencing is an excellent technology for detecting and quantifying DNA methylation patterns in a wide variety of species, but optimized data analysis pipelines exist only for a small number of species and are missing for many important crop plants. This is especially important as most existing benchmark studies have been performed on mammals with hardly any repetitive elements and without CHG and CHH methylation. Pipelines for the analysis of whole-genome bisulfite sequencing data usually consists of four steps: read trimming, read mapping, quantification of methylation levels, and prediction of differentially methylated regions (DMRs). Here we focus on read mapping, which is challenging because un-methylated cytosines are transformed to uracil during bisulfite treatment and to thymine during the subsequent polymerase chain reaction, and read mappers must be capable of dealing with this cytosine/thymine polymorphism. Several read mappers have been developed over the last years, with different strengths and weaknesses, but their performances have not been critically evaluated. Here, we compare eight read mappers: Bismark, BismarkBwt2, BSMAP, BS-Seeker2, Bwameth, GEM3, Segemehl, and GSNAP to assess the impact of the read-mapping results on the prediction of DMRs. We used simulated data generated from the genomes of Arabidopsis thaliana, Brassica napus, Glycine max, Solanum tuberosum, and Zea mays, monitored the effects of the bisulfite conversion rate, the sequencing error rate, the maximum number of allowed mismatches, as well as the genome structure and size, and calculated precision, number of uniquely mapped reads, distribution of the mapped reads, run time, and memory consumption as features for benchmarking the eight read mappers mentioned above. Furthermore, we validated our findings using real-world data of Glycine max and showed the influence of the mapping step on DMR calling in WGBS pipelines. We found that the conversion rate had only a minor impact on the mapping quality and the number of uniquely mapped reads, whereas the error rate and the maximum number of allowed mismatches had a strong impact and leads to differences of the performance of the eight read mappers. In conclusion, we recommend BSMAP which needs the shortest run time and yields the highest precision, and Bismark which requires the smallest amount of memory and yields precision and high numbers of uniquely mapped reads.

15.
Sci Rep ; 10(1): 15209, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938988

RESUMO

HIV-1 associated neurocognitive disorder (HAND) is characterized by neuroinflammation and glial activation that, together with the release of viral proteins, trigger a pathogenic cascade resulting in synaptodendritic damage and neurodegeneration that lead to cognitive impairment. However, the molecular events underlying HIV neuropathogenesis remain elusive, mainly due to lack of brain-representative experimental systems to study HIV-CNS pathology. To fill this gap, we developed a three-dimensional (3D) human brain organoid (hBORG) model containing major cell types important for HIV-1 neuropathogenesis; neurons and astrocytes along with incorporation of HIV-infected microglia. Both infected and uninfected microglia infiltrated into hBORGs resulting in a triculture system (MG-hBORG) that mirrors the multicellular network observed in HIV-infected human brain. Moreover, the MG-hBORG model supported productive viral infection and exhibited increased inflammatory response by HIV-infected MG-hBORGs, releasing tumor necrosis factor (TNF-α) and interleukin-1 (IL-1ß) and thereby mimicking the chronic neuroinflammatory environment observed in HIV-infected individuals. This model offers great promise for basic understanding of how HIV-1 infection alters the CNS compartment and induces pathological changes, paving the way for discovery of biomarkers and new therapeutic targets.


Assuntos
Encéfalo/citologia , Infecções por HIV/complicações , HIV-1/patogenicidade , Transtornos Neurocognitivos/patologia , Organoides/citologia , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/virologia , Diferenciação Celular , Meios de Cultura/química , Células HEK293 , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Humanos , Interleucina-1beta/metabolismo , Modelos Anatômicos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Células-Tronco Neurais/virologia , Transtornos Neurocognitivos/etiologia , Transtornos Neurocognitivos/metabolismo , Técnicas de Cultura de Órgãos , Organoides/metabolismo , Organoides/patologia , Organoides/virologia , Fator de Necrose Tumoral alfa/metabolismo , Replicação Viral
16.
Clin Case Rep ; 8(12): 2878-2882, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33363842

RESUMO

This case highlights the rare entity, salivary duct carcinoma (SDC), which is difficult to diagnose and manage. It is the first published case of a metastatic, HER2-positive parotid SDC successfully treated by a dual anti-HER2 treatment associated to a chemotherapy.

17.
FEBS Lett ; 591(20): 3319-3332, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28892135

RESUMO

High glucose transporter 1 (Glut1) surface expression is associated with increased glycolytic activity in activated CD4+ T cells. Phosphatidylinositide 3-kinases (PI3K) activation measured by p-Akt and OX40 is elevated in CD4+Glut1+ T cells from HIV+ subjects. TCR engagement of CD4+Glut1+ T cells from HIV+ subjects demonstrates hyperresponsive PI3K-mammalian target of rapamycin signaling. High basal Glut1 and OX40 on CD4+ T cells from combination antiretroviral therapy (cART)-treated HIV+ patients represent a sufficiently metabolically active state permissive for HIV infection in vitro without external stimuli. The majority of CD4+OX40+ T cells express Glut1, thus OX40 rather than Glut1 itself may facilitate HIV infection. Furthermore, infection of CD4+ T cells is limited by p110γ PI3K inhibition. Modulating glucose metabolism may limit cellular activation and prevent residual HIV replication in 'virologically suppressed' cART-treated HIV+ persons.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/metabolismo , Transportador de Glucose Tipo 1/imunologia , Infecções por HIV/metabolismo , Receptores OX40/imunologia , Adulto , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Proliferação de Células , Classe Ib de Fosfatidilinositol 3-Quinase/genética , Classe Ib de Fosfatidilinositol 3-Quinase/imunologia , Regulação da Expressão Gênica , Transportador de Glucose Tipo 1/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/crescimento & desenvolvimento , Humanos , Ativação Linfocitária , Masculino , Inibidores de Fosfoinositídeo-3 Quinase , Cultura Primária de Células , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/imunologia , Receptores OX40/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/imunologia , Replicação Viral/efeitos dos fármacos
18.
Curr HIV Res ; 9(4): 209-22, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21675943

RESUMO

Extracellular adenosine triphosphate (eATP) is a potent molecule that has the capacity to modulate various aspects of cell functions including gene expression. This element of modulation is essential to the role of ATP as a therapeutic agent. The hypothesis presented is that ATP can have an important impact on the treatment of HIV infection. This is supported in part by published research, although a much greater role for ATP is suggested than prior authors ever thought possible. ATP has the ability to enhance the immune system and could thus improve the host's own defense mechanisms to eradicate the virus-infected cells and restore normal immune function. This could provide effective therapy when used in conjunction with highly active antiretroviral therapies (HAART) to eliminate the latently infected cells. The key lies in applying ATP through the methodology described. This article presents a strategy for using ATP therapeutically along with background evidence to substantiate the importance of using ATP in the treatment of HIV infection.


Assuntos
Trifosfato de Adenosina/uso terapêutico , Adjuvantes Imunológicos/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Quimioterapia Combinada , Humanos
19.
Biochem Biophys Res Commun ; 314(4): 1126-32, 2004 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-14751250

RESUMO

HIV-1 Vpr is a protein with multiple functions. It has been suggested that such pleiotropic effects by a viral protein may be mediated by its association with viral and cellular proteins or through modulation of expression of specific cellular genes. To address this, we used cDNA microarray techniques to analyze the regulation of a panel of host cellular genes by HIV-1 Vpr using isogenic HIV-1 either with or without Vpr expression. Results indicate that Vpr downregulated the expression of genes involved in cell cycle/proliferation regulation, DNA repair, tumor antigens, and immune activation factors, and upregulated many ribosomal and structural proteins. These results for the first time reveal the involvement of several potential cellular genes, which may be useful, both for understanding Vpr functions and for the development of therapeutics targeting the Vpr molecule.


Assuntos
Regulação da Expressão Gênica/fisiologia , Produtos do Gene vpr/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Western Blotting , DNA Complementar , HIV-1/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Produtos do Gene vpr do Vírus da Imunodeficiência Humana
20.
Virology ; 328(1): 89-100, 2004 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-15380361

RESUMO

HIV-1 Vpr has been shown to transactivate LTR-directed expression through its interaction with several proteins of cellular origin including the glucocorticoid receptor (GR). Upon activation, steroid receptors bind to proteins containing the signature motif LxxLL, translocate into the nucleus, bind to their response element, and activate transcription. The presence of such motifs in HIV-1 Vpr has prompted us to undertake the analysis of the role of specific leucine residue(s) involved in Vpr-GR interaction, subcellular localization and its effect on Vpr-GR-mediated transactivation. The individual leucine residues present in H I, II, and III were mutated in the Vpr molecule and evaluated for their ability to interact with GR, transactivate GRE and HIV-1 LTR promoters, and their colocalization with GR. While Vpr mutants L42 and L67 showed reduced activation, substitutions at L20, L23, L26, L39, L64, and L68 exhibited a similar and slightly higher level of activation compared to Vprwt. Interestingly, a substitution at residue L22 resulted in a significantly higher GRE and HIV-1 LTR transactivation (8- to 11-fold higher) in comparison to wild type. Confocal microscopy indicated that Vpr L22A exhibited a distinct condensed nuclear localization pattern different from the nuclear/perinuclear pattern noted with Vprwt. Further, electrophoretic mobility shift assay (EMSA) revealed that the VprL22A-GR complex had higher DNA-binding activity when compared to the wild type Vpr-GR complex. These results suggest a contrasting role for the leucine residues on HIV-1 LTR-directed transactivation dependent upon their location in Vpr.


Assuntos
Produtos do Gene vpr/fisiologia , Infecções por HIV/virologia , HIV-1/fisiologia , Leucina/fisiologia , Fragmentos de Peptídeos/fisiologia , Ativação Transcricional , Replicação Viral , Sequência de Aminoácidos , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Produtos do Gene vpr/química , Produtos do Gene vpr/genética , Produtos do Gene vpr/metabolismo , Repetição Terminal Longa de HIV , Humanos , Dados de Sequência Molecular , Mutação , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de HIV/metabolismo , Fatores de Tempo , Produtos do Gene vpr do Vírus da Imunodeficiência Humana
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