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1.
Medicina (Kaunas) ; 58(10)2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36295595

RESUMEN

Background and Objectives: This study aimed to evaluate the utility and accuracy of dual-energy automatic plaque removal (DE-APR) in patients with symptomatic peripheral arterial disease (PAD) using digital subtraction angiography (DSA) as the reference standard. Materials and Methods: We retrospectively analyzed 100 patients with PAD who underwent DE computed tomography angiography (DE-CTA) and DSA of the lower extremities. DE-CTA was used to generate APR subtracted images. In the three main arterial segments (aorto-iliac segment, femoro-popliteal segment, and below-the-knee segment), the presence or absence of hemodynamically significant stenosis (>50%) and calcification was assessed using the images. CTA data were analyzed using different imaging approaches (DE-standard reconstruction image (DE-SR), DE-APR maximum intensity projection image (APR), and DE-SR with APR). Results: For all segments evaluated, the sensitivity, specificity, and accuracy for detecting significant stenosis were 98.16%, 81.01%, and 89.58%, respectively, with DE-SR; 97.79%, 83.33%, and 90.56%, respectively, with APR; and 98.16%, 92.25%, and 95.20%, respectively, with DE-SR with APR. DE-SR with APR had greater accuracy than DE-SR or APR alone (p < 0.001 and p < 0.001, respectively). When analyzed based on vascular wall calcification, the accuracy of DE-SR with APR remained greater than 90% regardless of calcification severity, whereas DE-SR showed a considerable reduction in accuracy in moderate to severe calcification. In the case of APR, the degree of vascular wall calcification did not significantly influence the accuracy in the aorto-iliac and femoro-popliteal segments. DE-SR with APR achieved significantly higher diagnostic accuracy for all lower extremity segments in evaluating hemodynamically significant stenosis in patients with symptomatic PAD and transcended the impact of vascular wall calcification compared with DE-SR. Conclusions: APR demonstrated favorable diagnostic performance in the aorto-iliac and femoro-popliteal segments, exhibiting good agreement with DSA even in cases of moderate to severe vascular wall calcification.


Asunto(s)
Enfermedad Arterial Periférica , Calcificación Vascular , Humanos , Angiografía por Tomografía Computarizada/métodos , Constricción Patológica/diagnóstico por imagen , Estudios Retrospectivos , Sensibilidad y Especificidad , Angiografía de Substracción Digital/métodos , Enfermedad Arterial Periférica/diagnóstico por imagen , Calcificación Vascular/diagnóstico por imagen
2.
J Neurosci ; 37(34): 8292-8308, 2017 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-28747383

RESUMEN

Innate immune signaling is important in the pathophysiology of ischemia/reperfusion (stroke)-induced injury and recovery. Several lines of evidence support a central role for microglia in these processes. Recent work has identified Toll-like receptors (TLRs) and type I interferon (IFN) signaling in both ischemia/reperfusion-induced brain injury and ischemic preconditioning-mediated neuroprotection. To determine the effects of "ischemia/reperfusion-like" conditions on microglia, we performed genomic analyses on wild-type (WT) and TLR4-/- cultured microglia after sequential exposure to hypoxia/hypoglycemia and normoxia/normoglycemia (H/H-N/N). We observed increased expression of type 1 IFN-stimulated genes (ISGs) as the predominant transcriptomal feature of H/H-N/N-exposed WT, but not TLR4-/-, microglia. Microarray analysis on ex vivo sorted microglia from ipsilateral male mouse cortex after a transient in vivo ischemic pulse also demonstrated robust expression of ISGs. Type 1 IFNs, including the IFN-αs and IFN-ß, activate the interferon-α/ß receptor (IFNAR) complex. We confirmed both in vitro H/H-N/N- and in vivo ischemia/reperfusion-induced microglial ISG responses by quantitative real-time PCR and demonstrated that both were dependent on IFNAR1. We characterized the effects of hypoxia/hypoglycemia on phosphorylation of signal transducer and activator of transcription 1 (STAT1), release of type 1 IFNs, and surface expression of IFNAR1 in microglia. We demonstrated that IFN-ß induces dose-dependent secretion of ISG chemokines in cultured microglia and robust ISG expression in microglia both in vitro and in vivo Finally, we demonstrated that the microglial ISG chemokine responses to TLR4 agonists were dependent on TLR4 and IFNAR1. Together, these data suggest novel ischemia/reperfusion-induced pathways for both TLR4-dependent and -independent, IFNAR1-dependent, type 1 IFN signaling in microglia.SIGNIFICANCE STATEMENT Stroke is the fifth leading cause of death in the United States and is a leading cause of serious long-term disability worldwide. Innate immune responses are critical in stroke pathophysiology, and microglia are key cellular effectors in the CNS response to ischemia/reperfusion. Using a transcriptional analysis approach, we identified a robust interferon (IFN)-stimulated gene response within microglia exposed to ischemia/reperfusion in both in vitro and in vivo experimental paradigms. Using a number of complementary techniques, we have demonstrated that these responses are dependent on innate immune signaling components including Toll-like receptor-4 and type I IFNs. We have also elucidated several novel ischemia/reperfusion-induced microglial signaling mechanisms.


Asunto(s)
Isquemia Encefálica/metabolismo , Interferones/farmacología , Microglía/metabolismo , Receptor de Interferón alfa y beta/biosíntesis , Daño por Reperfusión/metabolismo , Receptor Toll-Like 4/deficiencia , Animales , Animales Recién Nacidos , Isquemia Encefálica/genética , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Expresión Génica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microglía/efectos de los fármacos , Receptor de Interferón alfa y beta/genética , Daño por Reperfusión/genética , Receptor Toll-Like 4/genética
3.
FASEB J ; 30(12): 4056-4070, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27609773

RESUMEN

Pulmonary fibrosis is a progressive and often fatal condition that is believed to be partially orchestrated by macrophages. Mechanisms that control migration of these cells into and within the lung remain undefined. We evaluated the contributions of the semaphorin receptor, plexin C1 (PLXNC1), and the exocytic calcium sensor, synaptotagmin 7 (Syt7), in these processes. We evaluated the role of PLXNC1 in macrophage migration by using Boyden chambers and scratch tests, characterized its contribution to experimentally induced lung fibrosis in mice, and defined the mechanism for our observations. Our findings reveal that relative to control participants, patients with idiopathic pulmonary fibrosis demonstrate excessive monocyte migration and underexpression of PLXNC1 in the lungs and circulation, a finding that is recapitulated in the setting of scleroderma-related interstitial lung disease. Relative to wild type, PLXNC1-/- mouse macrophages are excessively migratory, and PLXNC1-/- mice show exacerbated collagen accumulation in response to either inhaled bleomycin or inducible lung targeted TGF-ß1 overexpression. These findings are ameliorated by replacement of PLXNC1 on bone marrow-derived cells or by genetic deletion of Syt7. These data demonstrate the previously unrecognized observation that PLXNC1 deficiency permits Syt7-mediated macrophage migration and enhances mammalian lung fibrosis.-Peng, X., Moore, M., Mathur, A., Zhou, Y., Sun, H., Gan, Y., Herazo-Maya, J. D., Kaminski, N., Hu, X., Pan, H., Ryu, C., Osafo-Addo, A., Homer, R. J., Feghali-Bostwick, C., Fares, W. H., Gulati, M., Hu, B., Lee, C.-G., Elias, J. A., Herzog, E. L. Plexin C1 deficiency permits synaptotagmin 7-mediated macrophage migration and enhances mammalian lung fibrosis.


Asunto(s)
Macrófagos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Fibrosis Pulmonar/metabolismo , Receptores de Superficie Celular/metabolismo , Receptores Virales/metabolismo , Sinaptotagminas/metabolismo , Animales , Modelos Animales de Enfermedad , Humanos , Pulmón/metabolismo , Ratones Noqueados , Proteínas del Tejido Nervioso/deficiencia , Fibrosis Pulmonar/genética , Receptores de Superficie Celular/deficiencia , Receptores Virales/deficiencia , Factor de Crecimiento Transformador beta1/metabolismo
4.
Proc Natl Acad Sci U S A ; 107(43): 18575-80, 2010 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-20937878

RESUMEN

Foxp3 is a key transcription factor for differentiation and function of regulatory T (Treg) cells that is critical for maintaining immunological self-tolerance. Therefore, increasing Treg function by Foxp3 transduction to regulate an inflammatory immune response is an important goal for the treatment of autoimmune and allergic diseases. Here we have generated a cell-permeable Foxp3 protein by fusion with the unique human HHph-1-PTD (protein transduction domain), examined its regulatory function in T cells, and characterized its therapeutic effect in autoimmune and allergic disease models. HHph-1-Foxp3 was rapidly and effectively transduced into cells within 30 min and conferred suppressor function to CD4(+)CD25(-) T cells as well as directly inhibiting T-cell activation and proliferation. Systemic delivery of HHph-1 Foxp3 remarkably inhibited the autoimmune symptoms of scurfy mice and the development of colitis induced by scurfy or wild-type CD4 T cells. Moreover, intranasal delivery of HHph-1-Foxp3 strongly suppressed ovalbumin-induced allergic airway inflammation. These results demonstrate the clinical potential of the cell-permeable recombinant HHph-1-Foxp3 protein in autoimmune and hypersensitive allergic diseases.


Asunto(s)
Asma/terapia , Enfermedades Autoinmunes/terapia , Factores de Transcripción Forkhead/inmunología , Factores de Transcripción Forkhead/uso terapéutico , Enfermedades Inflamatorias del Intestino/terapia , Animales , Asma/inmunología , Enfermedades Autoinmunes/inmunología , Permeabilidad de la Membrana Celular , Modelos Animales de Enfermedad , Femenino , Factores de Transcripción Forkhead/administración & dosificación , Factores de Transcripción Forkhead/genética , Humanos , Enfermedades Inflamatorias del Intestino/inmunología , Activación de Linfocitos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Mutantes , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/uso terapéutico , Linfocitos T Reguladores/inmunología
5.
J Neurotrauma ; 40(19-20): 2118-2125, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37464770

RESUMEN

The pupillary light reflex (PLR) is an important biomarker for the detection and management of traumatic brain injury (TBI). We investigated the performance of PupilScreen, a smartphone-based pupillometry app, in classifying healthy control subjects and subjects with severe TBI in comparison to the current gold standard NeurOptics pupillometer (NPi-200 model with proprietary Neurological Pupil Index [NPi] TBI severity score). A total of 230 PLR video recordings taken using both the PupilScreen smartphone pupillometer and NeurOptics handheld device (NPi-200) pupillometer were collected from 33 subjects with severe TBI (sTBI) and 132 subjects who were healthy without self-reported neurological disease. Severe TBI status was determined by Glasgow Coma Scale (GCS) at the time of recording. The proprietary NPi score was collected from the NPi-200 pupillometer for each subject. Seven PLR curve morphological parameters were collected from the PupilScreen app for each subject. A comparison via t-test and via binary classification algorithm performance using NPi scores from the NPi-200 and PLR parameter data from the PupilScreen app was completed. This was used to determine how the frequently used NPi-200 proprietary NPi TBI severity score compares to the PupilScreen app in ability to distinguish between healthy and sTBI subjects. Binary classification models for this task were trained for the diagnosis of healthy or severe TBI using logistic regression, k-nearest neighbors, support vector machine, and random forest machine learning classification models. Overall classification accuracy, sensitivity, specificity, area under the curve, and F1 score values were calculated. Median GCS was 15 for the healthy cohort and 6 (interquartile range 2) for the severe TBI cohort. Smartphone app PLR parameters as well as NPi from the digital infrared pupillometer were significantly different between healthy and severe TBI cohorts; 33% of the study cohort had dark eye colors defined as brown eyes of varying shades. Across all classification models, the top performing PLR parameter combination for classifying subjects as healthy or sTBI for PupilScreen was maximum diameter, constriction velocity, maximum constriction velocity, and dilation velocity with accuracy, sensitivity, specificity, area under the curve (AUC), and F1 score of 87%, 85.9%, 88%, 0.869, and 0.85, respectively, in a random forest model. The proprietary NPi TBI severity score demonstrated greatest AUC value, F1 score, and sensitivity of 0.648, 0.567, and 50.9% respectively using a random forest classifier and greatest overall accuracy and specificity of 67.4% and 92.4% using a logistic regression model in the same classification task on the same dataset. The PupilScreen smartphone pupillometry app demonstrated binary healthy versus severe TBI classification ability greater than that of the NPi-200 proprietary NPi TBI severity score. These results may indicate the potential benefit of future study of this PupilScreen smartphone pupillometry application in comparison to the NPi-200 digital infrared pupillometer across the broader TBI spectrum, as well as in other neurological diseases.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Aplicaciones Móviles , Enfermedades del Sistema Nervioso , Humanos , Reflejo Pupilar , Teléfono Inteligente , Color del Ojo , Pupila , Lesiones Traumáticas del Encéfalo/diagnóstico
6.
J Chest Surg ; 56(1): 1-5, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36598118

RESUMEN

Background: The number of patients with incidentally identified pulmonary nodules is increasing. This study attempted to confirm the usefulness and safety of video-assisted thoracic surgery (VATS) core needle biopsy of pulmonary nodules. Methods: Data from 18 patients diagnosed with pulmonary nodules who underwent VATS core need biopsy were retrospectively reviewed. Results: Of the 18 patients, 15 had malignancies (primary lung cancer, n=14; metastatic lung cancer, n=1), and 3 had benign nodules. Mortality and pleural metastasis did not occur during the follow-up period. Conclusion: In patients with solitary pulmonary nodules that require tissue confirmation, computed tomography-guided percutaneous cutting needle biopsy or diagnostic pulmonary resection sometimes may not be feasible choices due to the location of the solitary pulmonary nodule or the patient's impaired pulmonary function, VATS core needle biopsy may be performed in these patients as an alternative method.

7.
Immune Netw ; 22(5): e40, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36381962

RESUMEN

Mesenchymal stem cells (MSCs) are attractive alternatives to conventional anti-asthmatic drugs for severe asthma. Mechanisms underlying the anti-asthmatic effects of MSCs have not yet been elucidated. This study evaluated the anti-asthmatic effects of intravenously administered MSCs, focusing on macrophages and monocytes. Seven-week-old transgenic (Tg) mice with lung-specific overexpression of IL-13 were used to simulate chronic asthma. MSCs were intravenously administered four days before sampling. We examined changes in immune cell subpopulations, gene expression, and histological phenotypes. IL-13 Tg mice exhibited diverse features of chronic asthma, including severe type 2 inflammation, airway fibrosis, and mucus metaplasia. Intravenous administration of MSCs attenuated these asthmatic features just four days after a single treatment. MSC treatment significantly reduced SiglecF-CD11c-CD11b+ monocyte-derived macrophages (MoMs) and inhibited the polarization of MoMs into M2 macrophages, especially M2a and M2c. Furthermore, MSCs downregulated the excessive accumulation of Ly6c- monocytes in the lungs. While an intravenous adoptive transfer of Ly6c- monocytes promoted the infiltration of MoM and Th2 inflammation, that of MSC-exposed Ly6c- monocytes did not. Ex vivo Ly6c- MoMs upregulated M2-related genes, which were reduced by MSC treatment. Molecules secreted by Ly6c- MoMs from IL-13 Tg mice lungs upregulated the expression of fibrosis-related genes in fibroblasts, which were also suppressed by MSC treatment. In conclusion, intravenously administered MSCs attenuate asthma phenotypes of chronic asthma by modulating macrophages. Identifying M2 macrophage subtypes revealed that exposure to MSCs transforms the phenotype and function of macrophages. We suggest that Ly6c- monocytes could be a therapeutic target for asthma management.

8.
Sci Rep ; 12(1): 9811, 2022 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-35697721

RESUMEN

Despite numerous previous studies, the full action mechanism of the pathogenesis of asthma remains undiscovered, and the need for further investigation is increasing in order to identify more effective target molecules. Recent attempts to develop more efficacious treatments for asthma have incorporated mesenchymal stem cell (MSC)-based cell therapies. This study aimed to evaluate the anti-asthmatic effects of MSCs primed with Liproxstatin-1, a potent ferroptosis inhibitor. In addition, we sought to examine the changes within macrophage populations and their characteristics in asthmatic conditions. Seven-week-old transgenic mice, constitutively overexpressing lung-specific interleukin (IL)-13, were used to simulate chronic asthma. Human umbilical cord-derived MSCs (hUC-MSCs) primed with Liproxstatin-1 were intratracheally administered four days prior to sampling. IL-13 transgenic mice demonstrated phenotypes of chronic asthma, including severe inflammation, goblet cell hyperplasia, and subepithelial fibrosis. Ly6C+M2 macrophages, found within the pro-inflammatory CD11c+CD11b+ macrophages, were upregulated and showed a strong correlation with lung eosinophil counts. Liproxstatin-1-primed hUC-MSCs showed enhanced ability to downregulate the activation of T helper type 2 cells compared to naïve MSCs in vitro and reduced airway inflammation, particularly Ly6C+M2 macrophages population, and fibrosis in vivo. In conclusion, intratracheal administration is an effective method of MSC delivery, and macrophages hold great potential as an additional therapeutic target for asthma.


Asunto(s)
Antiasmáticos , Asma , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Animales , Antiasmáticos/farmacología , Asma/patología , Fibrosis , Inflamación/patología , Macrófagos/metabolismo , Trasplante de Células Madre Mesenquimatosas/métodos , Ratones , Ratones Transgénicos
9.
J Clin Neurosci ; 105: 66-72, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36113244

RESUMEN

Clinical significance of increased clopidogrel response measured by VerifyNow P2Y12 assay is unclear; management guidelines are lacking in the context of neuroendovascular intervention. Our objective was to assess whether increased clopidogrel response predicts complications from endovascular aneurysm treatment requiring dual antiplatelet therapy. A single-institution, 9-year retrospective study of patients undergoing endovascular treatments for ruptured and unruptured aneurysms requiring aspirin and clopidogrel was conducted. Patients were grouped according to preoperative platelet inhibition in response to clopidogrel measured by the VerifyNow P2Y12 assay (VNP; P2Y12 reactivity units, PRU). Demographic and clinical features were compared across groups. Hemorrhagic complication rates (intracranial, major extracranial, minor extracranial) and thromboembolic complications (in-stent stenosis, stroke/transient ischemic attack) were compared, controlling for potential confounders and multiple comparisons. Data were collected from 284 patients across 317 procedures. Pre-operative VNP assays identified 9 % Extreme Responders (PRU ≤ 15), 13 % Hyper-Responders (PRU 16-60), 62 % Therapeutic Responders (PRU 61-214), 16 % Hypo-Responders (PRU ≥ 215). Increased response to clopidogrel was associated with increased risk of any hemorrhagic complication (≤60 PRU vs > 60 PRU; 39 % vs 24 %, P = 0.050); all intracranial hemorrhages occurred in patients with PRU > 60. Thromboembolic complications were similar between therapeutic and subtherapeutic patients (<215 PRU vs ≥ 215 PRU; 15 % vs 16 %, P = 0.835). Increased preoperative clopidogrel response is associated with increased rate of extracranial hemorrhagic complications in endovascular aneurysm treatments. Hyper-responders (16-60 PRU) and Extreme Responders (≤15 PRU) were not associated with intracranial hemorrhagic or thrombotic complications. Hypo-responders who underwent adjustment of antiplatelet therapy and neurointerventions did not experience higher rates of complications.


Asunto(s)
Aneurisma de la Aorta Abdominal , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Aneurisma Intracraneal , Tromboembolia , Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/cirugía , Aspirina/efectos adversos , Clopidogrel/uso terapéutico , Procedimientos Endovasculares/efectos adversos , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/tratamiento farmacológico , Aneurisma Intracraneal/cirugía , Inhibidores de Agregación Plaquetaria/efectos adversos , Estudios Retrospectivos , Tromboembolia/tratamiento farmacológico , Tromboembolia/etiología , Resultado del Tratamiento
10.
World Neurosurg ; 156: e374-e380, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34563718

RESUMEN

OBJECTIVE: Clopidogrel is a commonly used antiplatelet agent for the prevention of thromboembolic complications following neuroendovascular procedures, but anecdotal data have raised concern for the possibility that clopidogrel may induce severe, intolerable fatigue. The purpose of this study is to systematically investigate this phenomenon. METHODS: We performed a dual-institution, 9-year, retrospective study of patients undergoing clopidogrel therapy for neuroendovascular procedures. Patients were included only if their response to clopidogrel was assessed by platelet function testing using the VerifyNow P2Y12 (VNP) assay. Hyperresponse to clopidogrel was defined as P2Y12 reaction units ≤60. Patients were considered to have had clopidogrel-induced severe fatigue if the onset of symptoms followed the initiation of clopidogrel therapy; symptoms improved following a reduction in the dose of clopidogrel; and symptoms could not be attributed to any other medical explanation. RESULTS: Data were collected on 349 patients. Five patients (1.4%) met criteria for clopidogrel-induced severe fatigue. All 5 patients were female, ages 39-68. VNP assessments obtained while patients were symptomatic revealed hyperresponse to clopidogrel (0-22 P2Y12 reaction units). Symptoms improved in all 5 patients when the dose of clopidogrel was reduced by half. Notably, 30% of patients (n = 103) demonstrated a hyperresponse to clopidogrel on at least 1 VNP assessment, but 98 of these patients did not suffer from severe fatigue. CONCLUSIONS: A syndrome of severe fatigue and other constitutional symptoms is a rare but clinically significant side effect of hyperresponse to clopidogrel in patients undergoing neuroendovasular intervention.


Asunto(s)
Clopidogrel/efectos adversos , Hipersensibilidad a las Drogas/fisiopatología , Fatiga/inducido químicamente , Inhibidores de Agregación Plaquetaria/efectos adversos , Adulto , Anciano , Procedimientos Endovasculares , Femenino , Humanos , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Pruebas de Función Plaquetaria , Agonistas del Receptor Purinérgico P2Y/efectos adversos , Receptores Purinérgicos P2Y12 , Estudios Retrospectivos
12.
Vasc Specialist Int ; 32(4): 186-189, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28042559

RESUMEN

Hypercoagulable states have been associated with aortic thrombosis. Antiphospholipid syndrome (APS) is one of the commonest types of acquired thrombophilia. We report the case of successful anticoagulation management in an APS patient with mobile thrombi within the aorta. A 58-year-old male patient presented to the emergency department (ED) with right-sided hemiparesis. His first symptoms were noted approximately 12-16 hours before presentation to the ED. Magnetic resonance imaging of the brain showed acute embolic infarction of the left frontal and parietotemporal lobes. Transesophageal echocardiography (TEE) and computed tomography angiography (CTA) demonstrated mobile thrombi attached to the wall of the ascending aorta and aortic arch. The patient was diagnosed with APS based on positivity of anti-beta-2 glycoprotein 1 antibodies, and was initiated on anticoagulation therapy. Repeated TEE and CTA revealed complete resolution of the thrombi after 12 days of treatment; the patient was discharged well.

13.
Diabetes ; 58(11): 2525-35, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19690064

RESUMEN

OBJECTIVE: Insulin resistance is a major characteristic of type 2 diabetes and is causally associated with obesity. Inflammation plays an important role in obesity-associated insulin resistance, but the underlying mechanism remains unclear. Interleukin (IL)-10 is an anti-inflammatory cytokine with lower circulating levels in obese subjects, and acute treatment with IL-10 prevents lipid-induced insulin resistance. We examined the role of IL-10 in glucose homeostasis using transgenic mice with muscle-specific overexpression of IL-10 (MCK-IL10). RESEARCH DESIGN AND METHODS: MCK-IL10 and wild-type mice were fed a high-fat diet (HFD) for 3 weeks, and insulin sensitivity was determined using hyperinsulinemic-euglycemic clamps in conscious mice. Biochemical and molecular analyses were performed in muscle to assess glucose metabolism, insulin signaling, and inflammatory responses. RESULTS: MCK-IL10 mice developed with no obvious anomaly and showed increased whole-body insulin sensitivity. After 3 weeks of HFD, MCK-IL10 mice developed comparable obesity to wild-type littermates but remained insulin sensitive in skeletal muscle. This was mostly due to significant increases in glucose metabolism, insulin receptor substrate-1, and Akt activity in muscle. HFD increased macrophage-specific CD68 and F4/80 levels in wild-type muscle that was associated with marked increases in tumor necrosis factor-alpha, IL-6, and C-C motif chemokine receptor-2 levels. In contrast, MCK-IL10 mice were protected from diet-induced inflammatory response in muscle. CONCLUSIONS: These results demonstrate that IL-10 increases insulin sensitivity and protects skeletal muscle from obesity-associated macrophage infiltration, increases in inflammatory cytokines, and their deleterious effects on insulin signaling and glucose metabolism. Our findings provide novel insights into the role of anti-inflammatory cytokine in the treatment of type 2 diabetes.


Asunto(s)
Citocinas/fisiología , Grasas de la Dieta/farmacología , Resistencia a la Insulina/fisiología , Interleucina-10/genética , Macrófagos/fisiología , Músculo Esquelético/fisiología , Animales , Creatina Quinasa/genética , Creatina Quinasa/metabolismo , Citocinas/antagonistas & inhibidores , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatología , Modelos Animales de Enfermedad , Citometría de Flujo , Técnica de Clampeo de la Glucosa , Hiperinsulinismo , Inflamación/fisiopatología , Inflamación/prevención & control , Insulina/fisiología , Interleucina-10/metabolismo , Interleucina-10/farmacología , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiopatología
14.
Phys Chem Chem Phys ; 10(7): 974-82, 2008 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-18259636

RESUMEN

The oxidation and hydration kinetics of a proton conductor oxide, SrCe(0.95)Yb(0.05)O(2.975), were examined via conductivity relaxation upon a sudden change of oxygen activity in a fixed water-activity atmosphere, and vice versa, in the ranges of -4.0 < log a(O(2)) < or = 0.01 and -5.0 < log a(H(2)O) < -2.0 at 800 degrees C. It was found that under an oxygen-activity gradient in a fixed water-vapor-activity atmosphere, the conductivity relaxation with time is monotonic with a single relaxation time (as usual), yielding a chemical diffusivity that is unequivocally that of the component oxygen. In a water-activity gradient in a fixed oxygen activity atmosphere, on the other hand, the conductivity relaxation appears quite unusual, exhibiting an extremum after an initial transient. The conductivity relaxation upon hydration or oxidation, in general, is quantitatively analyzed in terms of two apparent chemical diffusivities for component oxygen and hydrogen, respectively. The inner workings of hydration is discussed, and the as-evaluated chemical diffusivities are reported and compared with the conventional chemical diffusivity of water.


Asunto(s)
Cerio/química , Óxidos/química , Oxígeno/química , Protones , Estroncio/química , Iterbio/química , Atmósfera , Conductividad Eléctrica , Cinética , Oxidación-Reducción , Factores de Tiempo , Agua/química
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