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1.
Circulation ; 147(8): 669-685, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36591786

RESUMO

BACKGROUND: Epsin endocytic adaptor proteins are implicated in the progression of atherosclerosis; however, the underlying molecular mechanisms have not yet been fully defined. In this study, we determined how epsins enhance endothelial-to-mesenchymal transition (EndoMT) in atherosclerosis and assessed the efficacy of a therapeutic peptide in a preclinical model of this disease. METHODS: Using single-cell RNA sequencing combined with molecular, cellular, and biochemical analyses, we investigated the role of epsins in stimulating EndoMT using knockout in Apoe-/- and lineage tracing/proprotein convertase subtilisin/kexin type 9 serine protease mutant viral-induced atherosclerotic mouse models. The therapeutic efficacy of a synthetic peptide targeting atherosclerotic plaques was then assessed in Apoe-/- mice. RESULTS: Single-cell RNA sequencing and lineage tracing revealed that epsins 1 and 2 promote EndoMT and that the loss of endothelial epsins inhibits EndoMT marker expression and transforming growth factor-ß signaling in vitro and in atherosclerotic mice, which is associated with smaller lesions in the Apoe-/- mouse model. Mechanistically, the loss of endothelial cell epsins results in increased fibroblast growth factor receptor-1 expression, which inhibits transforming growth factor-ß signaling and EndoMT. Epsins directly bind ubiquitinated fibroblast growth factor receptor-1 through their ubiquitin-interacting motif, which results in endocytosis and degradation of this receptor complex. Consequently, administration of a synthetic ubiquitin-interacting motif-containing peptide atheroma ubiquitin-interacting motif peptide inhibitor significantly attenuates EndoMT and progression of atherosclerosis. CONCLUSIONS: We conclude that epsins potentiate EndoMT during atherogenesis by increasing transforming growth factor-ß signaling through fibroblast growth factor receptor-1 internalization and degradation. Inhibition of EndoMT by reducing epsin-fibroblast growth factor receptor-1 interaction with a therapeutic peptide may represent a novel treatment strategy for atherosclerosis.


Assuntos
Aterosclerose , Fator de Crescimento Transformador beta , Camundongos , Animais , Fatores de Crescimento de Fibroblastos , Apolipoproteínas E , Aterosclerose/genética , Receptores de Fatores de Crescimento de Fibroblastos , Fatores de Crescimento Transformadores , Ubiquitinas
3.
Circ Res ; 132(1): e22-e42, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36444722

RESUMO

BACKGROUND: Excess cholesterol accumulation in lesional macrophages elicits complex responses in atherosclerosis. Epsins, a family of endocytic adaptors, fuel the progression of atherosclerosis; however, the underlying mechanism and therapeutic potential of targeting Epsins remains unknown. In this study, we determined the role of Epsins in macrophage-mediated metabolic regulation. We then developed an innovative method to therapeutically target macrophage Epsins with specially designed S2P-conjugated lipid nanoparticles, which encapsulate small-interfering RNAs to suppress Epsins. METHODS: We used single-cell RNA sequencing with our newly developed algorithm MEBOCOST (Metabolite-mediated Cell Communication Modeling by Single Cell Transcriptome) to study cell-cell communications mediated by metabolites from sender cells and sensor proteins on receiver cells. Biomedical, cellular, and molecular approaches were utilized to investigate the role of macrophage Epsins in regulating lipid metabolism and transport. We performed this study using myeloid-specific Epsin double knockout (LysM-DKO) mice and mice with a genetic reduction of ABCG1 (ATP-binding cassette subfamily G member 1; LysM-DKO-ABCG1fl/+). The nanoparticles targeting lesional macrophages were developed to encapsulate interfering RNAs to treat atherosclerosis. RESULTS: We revealed that Epsins regulate lipid metabolism and transport in atherosclerotic macrophages. Inhibiting Epsins by nanotherapy halts inflammation and accelerates atheroma resolution. Harnessing lesional macrophage-specific nanoparticle delivery of Epsin small-interfering RNAs, we showed that silencing of macrophage Epsins diminished atherosclerotic plaque size and promoted plaque regression. Mechanistically, we demonstrated that Epsins bound to CD36 to facilitate lipid uptake by enhancing CD36 endocytosis and recycling. Conversely, Epsins promoted ABCG1 degradation via lysosomes and hampered ABCG1-mediated cholesterol efflux and reverse cholesterol transport. In a LysM-DKO-ABCG1fl/+ mouse model, enhanced cholesterol efflux and reverse transport due to Epsin deficiency was suppressed by the reduction of ABCG1. CONCLUSIONS: Our findings suggest that targeting Epsins in lesional macrophages may offer therapeutic benefits for advanced atherosclerosis by reducing CD36-mediated lipid uptake and increasing ABCG1-mediated cholesterol efflux.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Camundongos , Placa Aterosclerótica/metabolismo , Macrófagos/metabolismo , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Aterosclerose/metabolismo , Colesterol/metabolismo , Transportador 1 de Cassete de Ligação de ATP/metabolismo
4.
Can Assoc Radiol J ; 74(2): 241-250, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36083291

RESUMO

Introduction: This needs assessment evaluated residents' and medical students' knowledge of Competence by Design (CBD), perceived benefits of and challenges or barriers to the transition to CBD for residents, and perceived overall preparedness for the transition to CBD in diagnostic radiology. Materials and Methods: All diagnostic radiology residents and medical students in Canada were eligible to participate in this national cross-sectional, questionnaire-based needs assessment. Knowledge of CBD was evaluated through participants' self-reported rating of their knowledge of CBD on a 5-point Likert scale. Perceived benefits of and challenges or barriers to the transition to CBD for residents were rank ordered. Participants' overall self-reported preparedness for the transition to CBD was assessed on a 5-point Likert scale. Data were summarized by descriptive statistics and bivariate analyses were conducted as appropriate. Results: Ninety-four residents (n = 77) and medical students (n = 17) participated in this needs assessment. Participants' mean ± standard deviation self-reported rating of their overall knowledge of CBD was 2.86 ± .94. Provision of meaningful feedback to learners and learners' ability to identify their own educational needs were among the highest ranked perceived benefits of the transition to CBD, while demands on time and increased frequency of evaluation were among the highest ranked perceived challenges or barriers to the transition to CBD. Few participants reported being either "prepared" (4.7%) or "somewhat prepared" (14.0%) for the transition to CBD. Conclusion: Preparedness for the transition to CBD in diagnostic radiology may be improved. Targeted interventions to augment the preparedness of residents and medical students should be considered.


Assuntos
Internato e Residência , Radiologia , Estudantes de Medicina , Humanos , Estudos Transversais , Competência Clínica , Educação de Pós-Graduação em Medicina
5.
Cells ; 11(11)2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35681530

RESUMO

Endothelial-to-mesenchymal transition (EndoMT) is the process of endothelial cells progressively losing endothelial-specific markers and gaining mesenchymal phenotypes. In the normal physiological condition, EndoMT plays a fundamental role in forming the cardiac valves of the developing heart. However, EndoMT contributes to the development of various cardiovascular diseases (CVD), such as atherosclerosis, valve diseases, fibrosis, and pulmonary arterial hypertension (PAH). Therefore, a deeper understanding of the cellular and molecular mechanisms underlying EndoMT in CVD should provide urgently needed insights into reversing this condition. This review summarizes a 30-year span of relevant literature, delineating the EndoMT process in particular, key signaling pathways, and the underlying regulatory networks involved in CVD.


Assuntos
Doenças Cardiovasculares , Hipertensão Pulmonar , Doenças Cardiovasculares/metabolismo , Células Endoteliais/metabolismo , Endotélio/metabolismo , Transição Epitelial-Mesenquimal/genética , Humanos , Hipertensão Pulmonar/metabolismo
6.
Cureus ; 14(3): e23248, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35475045

RESUMO

A 63-year-old male with a 20-year history of a chronic, recurrent sacrococcygeal pilonidal cyst was referred to our outpatient clinic. He had received multiple surgical resections in the past with benign pathology. He presented with a verrucous wart-like midline mass on the superior gluteal cleft that had grown since his last resection. The patient subsequently underwent resection of the mass with bilateral gluteal rotational flaps. Pathology showed squamous cell carcinoma with tumor-free margins, and further imaging showed no evidence of metastatic disease. It is believed chronic inflammation with subsequent genetic and impaired DNA repair mechanisms is the leading cause of malignancy. The treatment of choice for pilonidal carcinoma is surgical resection with free margins. Reconstruction methods can be utilized to repair the tissue defect. Pilonidal carcinoma has high mortality risk with surgical treatment yielding a disease-free 5-year survival rate of 55% of patients and a high recurrence rate of 50%. The role of chemoradiotherapy is currently unclear.

7.
Front Cardiovasc Med ; 9: 841928, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252405

RESUMO

Diabetes mellitus is a worldwide health problem that usually comes with severe complications. There is no cure for diabetes yet and the threat of these complications is what keeps researchers investigating mechanisms and treatments for diabetes mellitus. Due to advancements in genomics, epigenomics, proteomics, and single-cell multiomics research, considerable progress has been made toward understanding the mechanisms of diabetes mellitus. In addition, investigation of the association between diabetes and other physiological systems revealed potentially novel pathways and targets involved in the initiation and progress of diabetes. This review focuses on current advancements in studying the mechanisms of diabetes by using genomic, epigenomic, proteomic, and single-cell multiomic analysis methods. It will also focus on recent findings pertaining to the relationship between diabetes and other biological processes, and new findings on the contribution of diabetes to several pathological conditions.

8.
J Clin Invest ; 132(10)2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35316218

RESUMO

Proliferation of latently infected CD4+ T cells with replication-competent proviruses is an important mechanism contributing to HIV persistence during antiretroviral therapy (ART). One approach to targeting this latent cell expansion is to inhibit mTOR, a regulatory kinase involved with cell growth, metabolism, and proliferation. Here, we determined the effects of chronic mTOR inhibition with rapamycin with or without T cell activation in SIV-infected rhesus macaques (RMs) on ART. Rapamycin perturbed the expression of multiple genes and signaling pathways important for cellular proliferation and substantially decreased the frequency of proliferating CD4+ memory T cells (TM cells) in blood and tissues. However, levels of cell-associated SIV DNA and SIV RNA were not markedly different between rapamycin-treated RMs and controls during ART. T cell activation with an anti-CD3LALA antibody induced increases in SIV RNA in plasma of RMs on rapamycin, consistent with SIV production. However, upon ART cessation, both rapamycin and CD3LALA-treated and control-treated RMs rebounded in less than 12 days, with no difference in the time to viral rebound or post-ART viral load set points. These results indicate that, while rapamycin can decrease the proliferation of CD4+ TM cells, chronic mTOR inhibition alone or in combination with T cell activation was not sufficient to disrupt the stability of the SIV reservoir.


Assuntos
Infecções por HIV , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Antirretrovirais/farmacologia , Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos , Proliferação de Células , Infecções por HIV/tratamento farmacológico , Macaca mulatta/genética , RNA , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/farmacologia , Carga Viral , Replicação Viral
9.
BMJ Open ; 11(8): e046310, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373296

RESUMO

INTRODUCTION: Regardless of having effective vaccines against COVID-19, containment measures such as enhanced physical distancing and good practice of personal hygiene remain the mainstay of controlling the COVID-19 pandemic. Countries across Asia have imposed these containment measures to varying extents. However, residents in different countries would have a differing degree of compliance to these containment measures potentially due to differences in the level of awareness and motivation in the early phase of pandemic. OBJECTIVES: In our study, we aimed to describe and correlate the level of knowledge and attitude with the level of compliance with personal hygiene and physical distancing practices among Asian countries in the early phase of pandemic. METHODS: A multinational cross-sectional study was carried out using electronic surveys between May and June 2020 across 14 geographical areas. Subjects aged 21 years and above were invited to participate through social media, word of mouth and electronic mail. RESULTS: Among the 2574 responses obtained, 762 (29.6%) participants were from East Asia and 1812 (70.4%) were from Southeast Asia (SEA). A greater proportion of participants from SEA will practise physical distancing as long as it takes (72.8% vs 60.6%). Having safe distancing practices such as standing more than 1 or 2 m apart (AdjOR 5.09 95% CI (1.08 to 24.01)) or more than 3 or 4 m apart (AdjOR 7.05 95% CI (1.32 to 37.67)), wearing a mask when they had influenza-like symptoms before the COVID-19 pandemic, preferring online news channels such as online news websites/applications (AdjOR 1.73 95% CI (1.21 to 2.49)) and social media (AdjOR 1.68 95% CI (1.13 to 2.50) as sources of obtaining information about COVID-19 and high psychological well-being (AdjOR 1.39 95% CI (1.04 to 1.87)) were independent factors associated with high compliance. CONCLUSIONS: We found factors associated with high compliance behaviour against COVID-19 in the early phase of pandemic and it will be useful to consider them in risk assessment, communication and pandemic preparedness.


Assuntos
COVID-19 , Pandemias , Vacinas contra COVID-19 , Estudos Transversais , Humanos , Pandemias/prevenção & controle , SARS-CoV-2 , Inquéritos e Questionários
10.
Cells ; 10(8)2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34440686

RESUMO

Background: The endothelial epsin 1 and 2 endocytic adaptor proteins play an important role in atherosclerosis by regulating the degradation of the calcium release channel inositol 1,4,5-trisphosphate receptor type 1 (IP3R1). In this study, we sought to identify additional targets responsible for epsin-mediated atherosclerotic endothelial cell activation and inflammation in vitro and in vivo. Methods: Atherosclerotic ApoE-/- mice and ApoE-/- mice with an endothelial cell-specific deletion of epsin 1 on a global epsin 2 knock-out background (EC-iDKO/ApoE-/-), and aortic endothelial cells isolated from these mice, were used to examine inflammatory signaling in the endothelium. Results: Inflammatory signaling was significantly abrogated by both acute (tumor necrosis factor-α (TNFα) or lipopolysaccharide (LPS)) and chronic (oxidized low-density lipoprotein (oxLDL)) stimuli in EC-iDKO/ApoE-/- mice and murine aortic endothelial cells (MAECs) isolated from epsin-deficient animals when compared to ApoE-/- controls. Mechanistically, the epsin ubiquitin interacting motif (UIM) bound to Toll-like receptors (TLR) 2 and 4 to potentiate inflammatory signaling and deletion of the epsin UIM mitigated this interaction. Conclusions: The epsin endocytic adaptor proteins potentiate endothelial cell activation in acute and chronic models of atherogenesis. These studies further implicate epsins as therapeutic targets for the treatment of inflammation of the endothelium associated with atherosclerosis.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Inflamação , Transdução de Sinais , Animais , Aorta/metabolismo , Aterosclerose/etiologia , Células Endoteliais/patologia , Feminino , Lipoproteínas LDL/metabolismo , Masculino , Camundongos , Camundongos Knockout
11.
PLoS One ; 16(6): e0252835, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34097719

RESUMO

IMPORTANCE: Knowledge and attitude influence compliance and individuals' practices. The risk and protective factors associated with high compliance to these preventive measures are critical to enhancing pandemic preparedness. OBJECTIVE: This survey aims to assess differences in mental health, knowledge, attitudes, and practices (KAP) of preventive measures for COVID-19 amongst healthcare professionals (HCP) and non-healthcare professionals. DESIGN: Multi-national cross-sectional study was carried out using electronic surveys between May-June 2020. SETTING: Multi-national survey was distributed across 36 countries through social media, word-of-mouth, and electronic mail. PARTICIPANTS: Participants ≥21 years working in healthcare and non-healthcare related professions. MAIN OUTCOME: Risk factors determining the difference in KAP towards personal hygiene and social distancing measures during COVID-19 amongst HCP and non-HCP. RESULTS: HCP were significantly more knowledgeable on personal hygiene (AdjOR 1.45, 95% CI -1.14 to 1.83) and social distancing (AdjOR 1.31, 95% CI -1.06 to 1.61) compared to non-HCP. They were more likely to have a positive attitude towards personal hygiene and 1.5 times more willing to participate in the contact tracing app. There was high compliance towards personal hygiene and social distancing measures amongst HCP. HCP with high compliance were 1.8 times more likely to flourish and more likely to have a high sense of emotional (AdjOR 1.94, 95% CI (1.44 to 2.61), social (AdjOR 2.07, 95% CI -1.55 to 2.78), and psychological (AdjOR 2.13, 95% CI (1.59-2.85) well-being. CONCLUSION AND RELEVANCE: While healthcare professionals were more knowledgeable, had more positive attitudes, their higher sense of total well-being was seen to be more critical to enhance compliance. Therefore, focusing on the well-being of the general population would help to enhance their compliance towards the preventive measures for COVID-19.


Assuntos
COVID-19/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/psicologia , Pandemias/prevenção & controle , Cooperação do Paciente , Adulto , Estudos Transversais , Feminino , Saúde Global , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários
12.
J Neuroimaging ; 31(3): 480-492, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33930224

RESUMO

BACKGROUND AND PURPOSE: To describe MRI findings in Japanese macaque encephalomyelitis (JME) with emphasis on lesion characteristics, lesion evolution, normal-appearing brain tissue, and similarities to human demyelinating disease. METHODS: MRI data were obtained from 114 Japanese macaques, 30 presenting neurological signs of JME. All animals were screened for presence of T2 -weighted white matter signal hyperintensities; animals with behavioral signs of JME were additionally screened for contrast-enhancing lesions. Whole-brain quantitative T1 maps were collected, and histogram analysis was performed with regression across age to evaluate microstructural changes in normal appearing brain tissue in JME and neurologically normal animals. Quantitative estimates of blood-brain-barrier (BBB) permeability to gadolinium-based-contrast agent (GBCA) were obtained in acute, GBCA-enhancing lesions. Longitudinal imaging data were acquired for 15 JME animals. RESULTS: One hundred and seventy-three focal GBCA-enhancing lesions were identified in 30 animals demonstrating behavioral signs of neurological dysfunction. JME GBCA-enhancing lesions were typically focal and ovoid, demonstrating highest BBB GBCA permeability in the lesion core, similar to acute, focal multiple sclerosis lesions. New GBCA-enhancing lesions arose rapidly from normal-appearing tissue, and BBB permeability remained elevated for weeks. T1 values in normal-appearing tissue were significantly associated with age, but not with sex or disease. CONCLUSIONS: Intense, focal neuroinflammation is a key MRI finding in JME. Several features of JME compare directly to human inflammatory demyelinating diseases. Investigation of JME combined with the development and validation of noninvasive imaging biomarkers offers substantial potential to improve diagnostic specificity and contribute to the understanding of human demyelinating diseases.


Assuntos
Barreira Hematoencefálica/fisiologia , Encéfalo/diagnóstico por imagem , Encefalomielite/patologia , Encefalomielite/veterinária , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/patologia , Adolescente , Adulto , Animais , Encéfalo/patologia , Criança , Pré-Escolar , Meios de Contraste , Encefalomielite/diagnóstico por imagem , Feminino , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/diagnóstico por imagem , Humanos , Lactente , Inflamação/patologia , Macaca fuscata , Imageamento por Ressonância Magnética/métodos , Masculino
13.
J Gastroenterol Hepatol ; 36(8): 2187-2197, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33615534

RESUMO

BACKGROUND AND AIM: Gastrointestinal manifestations of the coronavirus disease 2019 (COVID-19) pandemic may mimic irritable bowel syndrome (IBS), and social distancing measures may affect IBS patients negatively. We aimed to study the impact of COVID-19 on respondents with self-reported IBS. METHODS: We conducted an anonymized survey from May to June 2020 in 33 countries. Knowledge, attitudes, and practices on personal hygiene and social distancing as well as psychological impact of COVID-19 were assessed. Statistical analysis was performed to determine differences in well-being and compliance to social distancing measures between respondents with and without self-reported IBS. Factors associated with improvement or worsening of IBS symptoms were evaluated. RESULTS: Out of 2704 respondents, 2024 (74.9%) did not have IBS, 305 (11.3%) had self-reported IBS, and 374 (13.8%) did not know what IBS was. Self-reported IBS respondents reported significantly worse emotional, social, and psychological well-being compared with non-IBS respondents and were less compliant to social distancing measures (28.2% vs 35.3%, P = 0.029); 61.6% reported no change, 26.6% reported improvement, and 11.8% reported worsening IBS symptoms. Higher proportion of respondents with no change in IBS symptoms were willing to practice social distancing indefinitely versus those who deteriorated (74.9% vs 51.4%, P = 0.016). In multivariate analysis, willingness to continue social distancing for another 2-3 weeks (vs longer period) was significantly associated with higher odds of worsening IBS. CONCLUSION: Our study showed that self-reported IBS respondents had worse well-being and compliance to social distancing measures than non-IBS respondents. Future research will focus on occupational stress and dietary changes during COVID-19 that may influence IBS.


Assuntos
COVID-19/epidemiologia , Síndrome do Intestino Irritável/epidemiologia , Pandemias , Cooperação do Paciente , SARS-CoV-2 , Autorrelato , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Retrospectivos , Singapura/epidemiologia , Inquéritos e Questionários
14.
Ann Clin Transl Neurol ; 8(2): 456-470, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33440071

RESUMO

OBJECTIVE: To determine whether animals with Japanese macaque encephalomyelitis (JME), a spontaneous demyelinating disease similar to multiple sclerosis (MS), harbor myelin-specific T cells in their central nervous system (CNS) and periphery. METHODS: Mononuclear cells (MNCs) from CNS lesions, cervical lymph nodes (LNs) and peripheral blood of Japanese macaques (JMs) with JME, and cervical LN and blood MNCs from healthy controls or animals with non-JME conditions were analyzed for the presence of myelin-specific T cells and changes in interleukin 17 (IL-17) and interferon gamma (IFNγ) expression. RESULTS: Demyelinating JME lesions contained CD4+ T cells and CD8+ T cells specific to myelin oligodendrocyte glycoprotein (MOG), myelin basic protein (MBP), and/or proteolipid protein (PLP). CD8+ T-cell responses were absent in JME peripheral blood, and in age- and sex-matched controls. However, CD4+ Th1 and Th17 responses were detected in JME peripheral blood versus controls. Cervical LN MNCs from eight of nine JME animals had CD3+ T cells specific for MOG, MBP, and PLP that were not detected in controls. Mapping myelin epitopes revealed a heterogeneity in responses among JME animals. Comparison of myelin antigen sequences with those of JM rhadinovirus (JMRV), which is found in JME lesions, identified six viral open reading frames (ORFs) with similarities to myelin antigen sequences. Overlapping peptides to these JMRV ORFs did not induce IFNγ responses. INTERPRETATIONS: JME possesses an immune-mediated component that involves both CD4+ and CD8+ T cells specific for myelin antigens. JME may shed new light on inflammatory demyelinating disease pathogenesis linked to gamma-herpesvirus infection.


Assuntos
Doenças Desmielinizantes/diagnóstico por imagem , Doenças Desmielinizantes/patologia , Encefalomielite/diagnóstico por imagem , Encefalomielite/patologia , Bainha de Mielina/imunologia , Linfócitos T/imunologia , Animais , Doenças Autoimunes/imunologia , Doenças Desmielinizantes/virologia , Encefalomielite/virologia , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Epitopos/genética , Epitopos/imunologia , Feminino , Infecções por Herpesviridae/imunologia , Interferon gama/análise , Interleucina-17/análise , Macaca fuscata , Masculino , Doenças dos Macacos , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/imunologia , Proteína Proteolipídica de Mielina/genética , Proteína Proteolipídica de Mielina/imunologia , Bainha de Mielina/patologia , Glicoproteína Mielina-Oligodendrócito/genética , Glicoproteína Mielina-Oligodendrócito/imunologia , Rhadinovirus/genética , Rhadinovirus/imunologia
15.
J Virol ; 95(5)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33328302

RESUMO

The CD200-CD200R pathway is involved in inhibition of immune responses, and the importance of this pathway to infectious disease is highlighted by the fact that viral CD200 (vCD200) molecules have been found to be encoded by several DNA viruses, including the human gammaherpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV), and the closely related rhesus macaque rhadinovirus (RRV). KSHV vCD200 is the most extensively studied vCD200 molecule, however, the only herpesvirus vCD200 molecule to be examined in vivo is that encoded by RRV. Our prior studies have demonstrated that RRV vCD200 is a functional CD200 homologue that is capable of affecting immune responses in vivo, and further, that RRV can express a secreted form of vCD200 (vCD200-Sec) during infection. Despite this information, RRV vCD200 has not been examined specifically for effects on RM CD200R signaling, and the functionality of vCD200-Sec has not been examined in any context. Thus, we developed an in vitro model system in which B cells expressing vCD200 were utilized to assess the effects of this molecule on the regulation of myeloid cells expressing RM CD200R, mimicking interactions that are predicted to occur in vivo Our findings suggest that RRV vCD200 can bind and induce functional signals through RM CD200R, while vCD200-Sec represents a non-functional protein incapable of affecting CD200R signaling. We also provide the first demonstration of the function of RM CD200, which appears to possess more robust signaling capabilities than RRV vCD200, and also show that KSHV vCD200 does not efficiently induce signaling via RM CD200R.IMPORTANCE Viral CD200 homologues are encoded by KSHV and the closely related RRV. Though RRV vCD200 has been examined, questions still exist in regard to the ability of this molecule to induce signaling via rhesus macaque CD200R, as well as the potential function of a secreted form of vCD200. Further, all previous in vitro studies of RRV vCD200 have utilized an Fc fusion protein to examine functionality, which does not replicate the structural properties of the membrane-associated form of vCD200 that is naturally produced during RRV infection. In this study, we demonstrate for the first time that membrane-expressed RRV vCD200 is capable of inducing signal transduction via RM CD200R, while the secreted form of vCD200 appears to be non-functional. Further, we also demonstrate that RM CD200 induces signaling via RM CD200R, and is more robust than RRV vCD200, while KSHV vCD200 does not appear to induce efficient signaling via RM CD200R.

16.
J Clin Invest ; 131(1)2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-32960814

RESUMO

Estrogen receptor-negative (ER-negative) breast cancer is thought to be more malignant and devastating than ER-positive breast cancer. ER-negative breast cancer exhibits elevated NF-κB activity, but how this abnormally high NF-κB activity is maintained is poorly understood. The importance of linear ubiquitination, which is generated by the linear ubiquitin chain assembly complex (LUBAC), is increasingly appreciated in NF-κB signaling, which regulates cell activation and death. Here, we showed that epsin proteins, a family of ubiquitin-binding endocytic adaptors, interacted with LUBAC via its ubiquitin-interacting motif and bound LUBAC's bona fide substrate NEMO via its N-terminal homolog (ENTH) domain. Furthermore, epsins promoted NF-κB essential modulator (NEMO) linear ubiquitination and served as scaffolds for recruiting other components of the IκB kinase (IKK) complex, resulting in the heightened IKK activation and sustained NF-κB signaling essential for the development of ER-negative breast cancer. Heightened epsin levels in ER-negative human breast cancer are associated with poor relapse-free survival. We showed that transgenic and pharmacological approaches eliminating epsins potently impeded breast cancer development in both spontaneous and patient-derived xenograft breast cancer mouse models. Our findings established the pivotal role epsins played in promoting breast cancer. Thus, targeting epsins may represent a strategy to restrain NF-κB signaling and provide an important perspective into ER-negative breast cancer treatment.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Mamárias Animais/metabolismo , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Ubiquitinação , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/patologia , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/genética
17.
Nat Commun ; 11(1): 3984, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32770009

RESUMO

The epsin family of endocytic adapter proteins are widely expressed, and interact with both proteins and lipids to regulate a variety of cell functions. However, the role of epsins in atherosclerosis is poorly understood. Here, we show that deletion of endothelial epsin proteins reduces inflammation and attenuates atherosclerosis using both cell culture and mouse models of this disease. In atherogenic cholesterol-treated murine aortic endothelial cells, epsins interact with the ubiquitinated endoplasmic reticulum protein inositol 1,4,5-trisphosphate receptor type 1 (IP3R1), which triggers proteasomal degradation of this calcium release channel. Epsins potentiate its degradation via this interaction. Genetic reduction of endothelial IP3R1 accelerates atherosclerosis, whereas deletion of endothelial epsins stabilizes IP3R1 and mitigates inflammation. Reduction of IP3R1 in epsin-deficient mice restores atherosclerotic progression. Taken together, epsin-mediated degradation of IP3R1 represents a previously undiscovered biological role for epsin proteins and may provide new therapeutic targets for the treatment of atherosclerosis and other diseases.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Aterosclerose/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Proteólise , Proteínas Adaptadoras de Transporte Vesicular/química , Animais , Aorta/metabolismo , Aorta/patologia , Aterosclerose/patologia , Cálcio/metabolismo , Colesterol/metabolismo , Células Endoteliais/metabolismo , Feminino , Deleção de Genes , Células HEK293 , Homeostase , Humanos , Inflamação/patologia , Masculino , Camundongos Knockout , Ligação Proteica , Domínios Proteicos , Ubiquitinação
18.
PLoS One ; 15(2): e0228484, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32017809

RESUMO

Rhesus macaque (RM) rhadinovirus (RRV) is a simian gamma-2 herpesvirus closely related to human Kaposi's sarcoma-associated herpesvirus (KSHV). RRV is associated with the development of diseases in simian immunodeficiency virus (SIV) co-infected RM that resemble KSHV-associated pathologies observed in HIV-infected humans, including B cell lymphoproliferative disorders (LPD) and lymphoma. Importantly, how de novo KSHV infection affects the expression of host genes in humans, and how these alterations in gene expression affect viral replication, latency, and disease is unknown. The utility of the RRV/RM infection model provides a novel approach to address these questions in vivo, and utilizing the RRV bacterial artificial chromosome (BAC) system, the effects of specific viral genes on host gene expression patterns can also be explored. To gain insight into the effects of RRV infection on global host gene expression patterns in vivo, and to simultaneously assess the contributions of the immune inhibitory viral CD200 (vCD200) molecule to host gene regulation, RNA-seq was performed on pre- and post-infection lymph node (LN) biopsy samples from RM infected with either BAC-derived WT (n = 4) or vCD200 mutant RRV (n = 4). A variety of genes were identified as being altered in LN tissue samples due to RRV infection, including cancer-associated genes activation-induced cytidine deaminase (AICDA), glypican-1 (GPC1), CX3C chemokine receptor 1 (CX3CR1), and Ras dexamethasone-induced 1 (RasD1). Further analyses also indicate that GPC1 may be associated with lymphomagenesis. Finally, comparison of infection groups identified the differential expression of host gene thioredoxin interacting protein (TXNIP), suggesting a possible mechanism by which vCD200 negatively affects RRV viral loads in vivo.


Assuntos
Perfilação da Expressão Gênica/veterinária , Infecções por Herpesviridae/veterinária , Rhadinovirus/patogenicidade , Infecções Tumorais por Vírus/veterinária , Animais , Receptor 1 de Quimiocina CX3C/genética , Transformação Celular Neoplásica/genética , Citidina Desaminase/genética , Regulação Neoplásica da Expressão Gênica , Glipicanas/genética , Infecções por Herpesviridae/genética , Tecido Linfoide/metabolismo , Macaca mulatta , Análise de Sequência de RNA/veterinária , Infecções Tumorais por Vírus/genética , Latência Viral , Replicação Viral , Proteínas ras/genética
19.
Cephalalgia ; 40(6): 586-596, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31752520

RESUMO

BACKGROUND: Many medically-refractory trigeminal neuralgia patients are non-responders to surgical treatment. Few studies have explored how trigeminal nerve characteristics relate to surgical outcome, and none have investigated the relationship between subcortical brain structure and treatment outcomes. METHODS: We retrospectively studied trigeminal neuralgia patients undergoing surgical treatment with microvascular decompression. Preoperative magnetic resonance imaging was used for manual tracing of trigeminal nerves and automated segmentation of hippocampus, amygdala, and thalamus. Nerve and subcortical structure volumes were compared between responders and non-responders and assessed for ability to predict postoperative pain outcome. RESULTS: In all, 359 trigeminal neuralgia patients treated surgically from 2005-2018 were identified. A total of 34 patients met the inclusion criteria (32 with classic and two with idiopathic trigeminal neuralgia). Across all patients, thalamus volume was reduced ipsilateral compared to contralateral to the side of pain. Between responders and non-responders, non-responders exhibited larger contralateral trigeminal nerve volume, and larger ipsilateral and contralateral hippocampus volume. Through receiver-operator characteristic curve analyses, contralateral hippocampus volume correctly classified treatment outcome in 82% of cases (91% sensitive, 78% specific, p = 0.008), and contralateral nerve volume correctly classified 81% of cases (91% sensitive, 75% specific, p < 0.001). Binomial logistic regression analysis showed that contralateral hippocampus and contralateral nerve volumes together classified outcome with 84% accuracy (Nagelkerke R2 = 65.1). CONCLUSION: Preoperative hippocampal and trigeminal nerve volume, measured on standard clinical magnetic resonance images, may predict early non-response to surgical treatment for trigeminal neuralgia. Treatment resistance in medically refractory trigeminal neuralgia may depend on the structural features of both the trigeminal nerve and structures involved in limbic components of chronic pain.


Assuntos
Hipocampo/patologia , Nervo Trigêmeo/patologia , Neuralgia do Trigêmeo/patologia , Neuralgia do Trigêmeo/cirurgia , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Cirurgia de Descompressão Microvascular , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
20.
J Immunol ; 203(11): 2928-2943, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31653683

RESUMO

Although IL-15 has been implicated in the pathogenic hyperimmune activation that drives progressive HIV and SIV infection, as well as in the generation of HIV/SIV target cells, it also supports NK and T cell homeostasis and effector activity, potentially benefiting the host. To understand the role of IL-15 in SIV infection and pathogenesis, we treated two cohorts of SIVmac239-infected rhesus macaques (RM; Macaca mulatta), one with chronic infection, the other with primary infection, with a rhesusized, IL-15-neutralizing mAb (versus an IgG isotype control) for up to 10 wk (n = 7-9 RM per group). In both cohorts, anti-IL-15 was highly efficient at blocking IL-15 signaling in vivo, causing 1) profound depletion of NK cells in blood and tissues throughout the treatment period; 2) substantial, albeit transient, depletion of CD8+ effector memory T cells (TEM) (but not the naive and central memory subsets); and 3) CD4+ and CD8+ TEM hyperproliferation. In primary infection, reduced frequencies of SIV-specific effector T cells in an extralymphoid tissue site were also observed. Despite these effects, the kinetics and extent of SIV replication, CD4+ T cell depletion, and the onset of AIDS were comparable between anti-IL-15- and control-treated groups in both cohorts. However, RM treated with anti-IL-15 during primary infection manifested accelerated reactivation of RM rhadinovirus. Thus, IL-15 support of NK cell and TEM homeostasis does not play a demonstrable, nonredundant role in SIV replication or CD4+ T cell deletion dynamics but may contribute to immune control of oncogenic γ-herpesviruses.


Assuntos
Interleucina-15/imunologia , Macaca mulatta/imunologia , Transdução de Sinais/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Feminino , Masculino , Vírus da Imunodeficiência Símia/patogenicidade
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