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1.
Retin Cases Brief Rep ; 17(1): 54-60, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33229912

RESUMO

PURPOSE: Three cases of dislocation of a Gore-Tex scleral-sutured EnVista intraocular lens are reported. The tensile strength of the lens eyelets under two suturing methods is assessed. Pursuant surgical considerations are discussed. METHODS: A chart review was performed to identify cases of scleral-sutured EnVista lens dislocations. In addition, six EnVista lenses were suspended in a balanced salt solution tank, tied either with suture over haptic or simple pass technique. Eyelet tensile strength was calculated by gradual addition of weights. Eyelet fracture position and width were measured. The tensile strength of one additional EnVista lens was assessed in open air. PATIENTS: In a retrospective, consecutive case series, three dislocated lenses were identified out of 17 surgeries from one institution. Two dislocations occurred postoperatively, and one occurred intraoperatively. RESULTS: The EnVista eyelet demonstrated greater tensile strength tied with the simple pass method (0.27 ± 0.017 N, n = 3) than with the suture over haptic method (0.15 ± 0.016 N, n = 3; P = 0.0015). Eyelet fracture location corresponded to tensile strength. The lens in air withstood greater tensile stress. CONCLUSION: Stress is placed on different regions of the eyelet with each suturing method. Simple pass may withstand greater tension and decrease risk for lens fracture, but the operating surgeon must consider multiple factors when forming an operative plan.


Assuntos
Lentes Intraoculares , Politetrafluoretileno , Humanos , Implante de Lente Intraocular/métodos , Estudos Retrospectivos , Resistência à Tração , Resistência à Flexão , Vitrectomia/métodos , Acuidade Visual , Suturas/efeitos adversos , Técnicas de Sutura , Fatores de Risco
2.
J Vasc Res ; 48(3): 261-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21099231

RESUMO

BACKGROUND/AIMS: The role of adventitial fibroblasts in the vascular inflammation observed in the adventitia of large vessels in numerous cardiovascular diseases remains unclear. Our objective was to explore the contribution of these cells to angiotensin II (Ang II)-induced aortic inflammation and adventitial expansion. METHODS: Cytokine production by primary human aortic adventitial fibroblasts (AoAF) in tissue culture was detected using multiplex ELISA, and increases in cytokine mRNA following Ang II stimulation were quantitated by real-time PCR. The ability of AoAF-derived MCP-1 to attract monocytes was studied in vitro using Boyden assays, and the resulting effect of the monocyte-AoAF interaction on fibroblast proliferation was measured in vitro using proliferation and (3)H-thymidine incorporation assays. Ang II-induced fibroblast proliferation was measured in vivo using aortic digestion of single cells followed by flow cytometric quantification of fibroblast numbers as well as fibroblast and PCNA immunostaining. The ability of monocytes to induce AoAF proliferation was demonstrated in vivo using CCR2(+/+) wild-type monocyte adoptive transfer into Ang II-stimulated CCR2-null mice which can produce MCP-1 but have cells lacking the MCP-1 receptor - CCR2. RESULTS: AoAF constitutively secreted numerous proinflammatory cytokines, particularly IL-6 and MCP-1, whose gene expressions were further upregulated in response to Ang II stimulation. AoAF-derived MCP-1 was potent in recruiting THP-1 monocytes in vitro, and these monocytes stimulated AoAF proliferation based on a flow cytometric assessment of cell number and (3)H-thymidine incorporation in tissue culture. In vivo, Ang II induced fibroblast proliferation, increased fibroblast and PCNA adventitial staining, and blunted inflammatory responses in the CCR2(-/-) background. Injection of CCR2(+/+) monocytes into Ang II-treated CCR2(-/-) mice restored adventitial thickening which resulted in increased fibrosis secondary to adventitial fibroblast proliferation. CONCLUSIONS: Our results suggest that Ang II-stimulates AoAF to recruit monocytes via fibroblast-derived MCP-1, and the recruited monocytes further activate fibroblast proliferation, adventitial thickening, and additional cytokine production. This fibroblast-monocyte amplification loop may critically mediate hallmarks of adventitial inflammation common to many cardiovascular diseases.


Assuntos
Angiotensina II/metabolismo , Aorta/imunologia , Tecido Conjuntivo/imunologia , Citocinas/metabolismo , Fibroblastos/imunologia , Mediadores da Inflamação/metabolismo , Inflamação/imunologia , Transferência Adotiva , Animais , Aorta/metabolismo , Aorta/patologia , Proliferação de Células , Células Cultivadas , Quimiocina CCL2/metabolismo , Quimiotaxia de Leucócito , Técnicas de Cocultura , Tecido Conjuntivo/metabolismo , Tecido Conjuntivo/patologia , Meios de Cultivo Condicionados/metabolismo , Citocinas/genética , Ensaio de Imunoadsorção Enzimática , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/imunologia , Monócitos/metabolismo , Comunicação Parácrina , Reação em Cadeia da Polimerase , Receptores CCR2/deficiência , Receptores CCR2/genética , Fatores de Tempo
3.
J Immunol ; 181(5): 3515-23, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18714024

RESUMO

The 5-lipoxygenase (5LO) produces leukotriene B(4) and 15-epilipoxin-A(4) (15-epi-LXA(4)). Phosphorylation at Ser(523) by protein kinase A (PKA) prevents 5LO shift to the perinuclear membrane. Atorvastatin and pioglitazone up-regulate 15-epi-LXA(4) production in the heart. We assessed whether phosphorylation of 5LO by PKA determines whether 5LO interacts with the membranous cytosolic phospholipase A(2) (cPLA(2)) to produce leukotriene B(4) or with cyclooxygenase-2 (COX2) to produce 15-epi-LXA(4). Rats received either pioglitazone, atorvastatin, pioglitazone plus atorvastatin, vehicle, or LPS. Rat myocardial cells were incubated with pioglitazone plus atorvastatin, pioglitazone plus atorvastatin plus H-89 (PKA inhibitor), H-89, or vehicle for 8 h. Pioglitazone and atorvastatin did not affect total 5LO expression. However, both increased 5LO levels in the cytosolic fraction. H-89 caused a shift of 5LO to the membranous fraction in atorvastatin- and pioglitazone-treated rats. Pioglitazone and atorvastatin increased phospho-5LO levels. H-89 attenuated this increase. Both pioglitazone and atorvastatin increased COX2 levels in the cytosolic fraction and the membranous fraction. H-89 prevented this increase. Pioglitazone and atorvastatin increased cPLA(2) expression in the membranous fraction. This effect was not attenuated by H-89. Pioglitazone plus atorvastatin increased 15-epi-LXA(4) levels. H-89 attenuated the effect of pioglitazone plus atorvastatin. Pioglitazone plus atorvastatin plus H-89 increased leukotriene B(4) levels. Coimmunoprecipitation showed that without H-89, atorvastatin and pioglitazone induced an interaction between 5LO and COX2 in the cytosolic fraction, whereas when H-89 was added, 5LO interacted with cPLA(2) on the membranous fraction. The 5LO phosphorylation determines whether 15-epi-LXA(4) (anti-inflammatory) or leukotriene B(4) (inflammatory mediator) is produced.


Assuntos
Araquidonato 5-Lipoxigenase/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ácidos Heptanoicos/farmacologia , Leucotrieno B4/biossíntese , Lipoxinas/biossíntese , Pirróis/farmacologia , Tiazolidinedionas/farmacologia , Animais , Atorvastatina , Regulação da Expressão Gênica/efeitos dos fármacos , Ácidos Heptanoicos/administração & dosagem , Fatores Imunológicos/genética , Isoquinolinas/farmacologia , Masculino , Miocárdio/citologia , Miocárdio/imunologia , Fosforilação , Pioglitazona , Pirróis/administração & dosagem , Ratos , Ratos Sprague-Dawley , Serina/metabolismo , Sulfonamidas/farmacologia , Tiazolidinedionas/administração & dosagem
4.
Am J Trop Med Hyg ; 100(5): 1223-1226, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30860012

RESUMO

Ocular toxocariasis can be vision threatening, and is commonly reported from tropical or subtropical regions. Knowledge of clinical manifestations from the United States, particularly in underserved areas such as the American South, is lacking. We report three cases of ocular toxocariasis in individuals from the Mississippi Delta, a rural community with prevalent poverty. Visual acuity was severely affected in two of the three cases. Increased awareness of ocular toxocariasis, which may have under-recognized frequency, will contribute to prompt diagnosis and treatment, which will ultimately improve patient health in the region.


Assuntos
Infecções Oculares Parasitárias/diagnóstico , População Rural , Toxocaríase/diagnóstico , Adulto , Animais , Anti-Helmínticos/uso terapêutico , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Olho/parasitologia , Infecções Oculares Parasitárias/tratamento farmacológico , Feminino , Humanos , Larva Migrans/diagnóstico , Masculino , Mississippi , Toxocara canis , Toxocaríase/tratamento farmacológico , Acuidade Visual , Adulto Jovem
5.
Circ Res ; 99(7): 723-30, 2006 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-16960103

RESUMO

The vasoconstrictor angiotensin II (Ang II) accelerates atherosclerosis by inducing vascular gene expression programs, producing monocyte recruitment, and vascular remodeling. In vascular smooth muscle cells (VSMCs), Ang II signaling activates interleukin (IL)-6 expression, a cytokine producing acute-phase inflammation, mediated by the transcription factor nuclear factor kappaB (NF-kappaB). The classical NF-kappaB activation pathway involves cytoplasmic-to-nuclear translocation of the potent RelA transactivating subunit; however, because nuclear RelA is present in VSMCs, the mechanism by which NF-kappaB activity is controlled is incompletely understood. In this study, we focus on early activation steps controlling RelA activation. Although Ang II only weakly induces approximately 1.5-fold RelA nuclear translocation, RelA is nevertheless required because short interfering RNA-mediated RelA knockdown inhibits inducible IL-6 expression. We find instead that Ang II stimulation rapidly induces RelA phosphorylation at serine residue 536, a critical regulatory site in its transactivating domain. Chromatin immunoprecipitation assays indicate no significant changes in total RelA binding to the native IL-6 promoter, but an apparent increase in fractional binding of phospho-Ser536 RelA. Inactivation of RhoA by treatment with Clostridium botulinum exoenzyme C3 exotoxin or expression of dominant negative RhoA blocks Ang II-inducible RelA Ser536 phosphorylation and IL-6 expression. Finally, enhanced phospho-Ser536 RelA formation in the aortae of rats chronically infused with Ang II was observed. Together, these data indicate a novel mechanism for Ang II-induced NF-kappaB activation in VSMCs, mediated by RhoA-induced phospho-Ser536 RelA formation, IL-6 expression, and vascular inflammation.


Assuntos
Angiotensina II/farmacologia , Interleucina-6/genética , Músculo Liso Vascular/metabolismo , NF-kappa B/metabolismo , Regiões Promotoras Genéticas , Fator de Transcrição RelA/metabolismo , Proteína rhoA de Ligação ao GTP/fisiologia , Animais , Aorta/citologia , Aorta/metabolismo , Interleucina-6/biossíntese , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , NF-kappa B/fisiologia , Fosforilação , Isoformas de Proteínas/metabolismo , Ratos , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/fisiologia
6.
Diabetes ; 55(5): 1252-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16644679

RESUMO

Evidence of diabetes-induced nuclear factor-kappaB (NF-kappaB) activation has been provided with DNA binding assays or nuclear localization with immunohistochemistry, but few studies have explored mechanisms involved. We examined effects of diabetes on proteins comprising NF-kappaB canonical and noncanonical activation pathways in the renal cortex of diabetic mice. Plasma concentrations of NF-kappaB-regulated cytokines were increased after 1 month of hyperglycemia, but most returned to control levels or lower by 3 months, when the same cytokines were increased significantly in renal cortex. Cytosolic content of NF-kappaB canonical pathway proteins did not differ between experimental groups after 3 months of diabetes, while NF-kappaB noncanonical pathway proteins were affected, including increased phosphorylation of inhibitor of kappaB kinase-alpha and several fold increases in NF-kappaB-inducing kinase and RelB, which were predominantly located in tubular epithelial cells. Nuclear content of all NF-kappaB pathway proteins was decreased by diabetes, with the largest change in RelB and p50 (approximately twofold decrease). Despite this decrease, measurable increases in protein binding to DNA in diabetic versus control nuclear extracts were observed with electrophoretic mobility shift assay. These results provide evidence for chronic NF-kappaB activation in the renal cortex of db/db mice and suggest a novel, diabetes-linked mechanism involving both canonical and noncanonical NF-kappaB pathway proteins.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Córtex Renal/metabolismo , NF-kappa B/metabolismo , Animais , Núcleo Celular/imunologia , Núcleo Celular/metabolismo , Quimiocinas/biossíntese , Citocinas/biossíntese , Citosol/imunologia , Citosol/metabolismo , DNA/metabolismo , Diabetes Mellitus Experimental/imunologia , Camundongos , NF-kappa B/classificação
7.
Ophthalmic Surg Lasers Imaging ; 43(4): 291-5, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589336

RESUMO

BACKGROUND AND OBJECTIVE: Chronic macular hole and inability to maintain prone positioning remain poor prognostic markers for successful macular hole closure. The authors revisited the role of autologous platelets as an adjunct to internal limiting membrane (ILM) peeling of chronic macular holes in patients unable to maintain prone positioning. PATIENTS AND METHODS: A retrospective case study was conducted on 13 eyes of 13 patients with full-thickness chronic macular hole (> 24 months). Each patient was unable to maintain prone positioning due to medical and physical comorbidities. Each eye was treated with pars plana vitrectomy, ILM peeling, autologous platelets, and C(3)F(8) gas tamponade. No positioning was advised postoperatively. All patients had complete ophthalmic examinations preoperatively and 1 day and 1, 3, and 6 months postoperatively with optical coherence tomography. Outcome measures were anatomic closure based on Tornambe classification, final best-corrected visual acuity, and improvement of quality of vision. RESULTS: All 13 patients completed 6 months' follow-up. Macular hole duration ranged from 2 to 5 years. There was a 100% macular hole closure rate at 1 and 6 months postoperatively. All patients reported subjective improvement in visual acuity as an improvement of an absolute central scotoma. At 6 months postoperatively, 38% of patients reported improved best-corrected visual acuity. There were no recurrences. CONCLUSION: Autologous platelets and ILM peeling may function synergistically to enhance chronic macular hole closure in patients unable to maintain prone positioning.


Assuntos
Membrana Basal/cirurgia , Plaquetas , Tamponamento Interno , Fluorocarbonos/administração & dosagem , Perfurações Retinianas/cirurgia , Vitrectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Decúbito Ventral , Perfurações Retinianas/diagnóstico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
8.
J Clin Invest ; 119(12): 3637-51, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19920349

RESUMO

Vascular inflammation contributes to cardiovascular diseases such as aortic aneurysm and dissection. However, the precise inflammatory pathways involved have not been clearly defined. We have shown here that subcutaneous infusion of Ang II, a vasopressor known to promote vascular inflammation, into older C57BL/6J mice induced aortic production of the proinflammatory cytokine IL-6 and the monocyte chemoattractant MCP-1. Production of these factors occurred predominantly in the tunica adventitia, along with macrophage recruitment, adventitial expansion, and development of thoracic and suprarenal aortic dissections. In contrast, a reduced incidence of dissections was observed after Ang II infusion into mice lacking either IL-6 or the MCP-1 receptor CCR2. Further analysis revealed that Ang II induced CCR2+CD14hiCD11bhiF4/80- macrophage accumulation selectively in aortic dissections and not in aortas from Il6-/- mice. Adoptive transfer of Ccr2+/+ monocytes into Ccr2-/- mice resulted in selective monocyte uptake into the ascending and suprarenal aorta in regions of enhanced ROS stress, with restoration of IL-6 secretion and increased incidence of dissection. In vitro, coculture of monocytes and aortic adventitial fibroblasts produced MCP-1- and IL-6-enriched conditioned medium that promoted differentiation of monocytes into macrophages, induced CD14 and CD11b upregulation, and induced MCP-1 and MMP-9 expression. These results suggest that leukocyte-fibroblast interactions in the aortic adventitia potentiate IL-6 production, inducing local monocyte recruitment and activation, thereby promoting MCP-1 secretion, vascular inflammation, ECM remodeling, and aortic destabilization.


Assuntos
Aneurisma Aórtico/etiologia , Dissecção Aórtica/etiologia , Quimiocina CCL2/fisiologia , Interleucina-6/fisiologia , Receptores CCR2/fisiologia , Transferência Adotiva , Dissecção Aórtica/patologia , Dissecção Aórtica/fisiopatologia , Angiotensina II/administração & dosagem , Animais , Aneurisma Aórtico/patologia , Aneurisma Aórtico/fisiopatologia , Sequência de Bases , Quimiocina CCL2/genética , Técnicas de Cocultura , Tecido Conjuntivo/patologia , Tecido Conjuntivo/fisiopatologia , Primers do DNA/genética , Modelos Animais de Doenças , Humanos , Inflamação/etiologia , Inflamação/patologia , Inflamação/fisiopatologia , Interleucina-6/deficiência , Interleucina-6/genética , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores CCR2/deficiência , Receptores CCR2/genética , Transdução de Sinais
9.
Curr Cardiol Rev ; 4(3): 179-92, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19936194

RESUMO

UNLABELLED: Interleukin-6 (IL-6) is a well-established, independent indicator of multiple distinct types of cardiovascular disease and all-cause mortality. In this review, we present current understanding of the multiple roles that IL-6 and its signaling pathways through glycoprotein 130 (gp130) play in cardiovascular homeostasis. IL-6 is highly inducible in vascular tissues through the actions of the angiotensin II (Ang II) peptide, where it acts in a paracrine manner to signal through two distinct mechanisms, the first being a classic membrane receptor initiated pathway and the second, a trans-signaling pathway, being able to induce responses even in tissues lacking the IL-6 receptor. Recent advances and new concepts in how its intracellular signaling pathways operate via the Janus kinase (JAK)-Signal Transducer and Activator of Transcription (STAT) are described. IL-6 has diverse actions in multiple cell types of cardiovascular importance, including endothelial cells, monocytes, platelets, hepatocytes and adipocytes. We discuss central roles of IL-6 in endothelial dysfunction, cellular inflammation by affecting monocyte activation/differentiation, cellular cytoprotective functions from reactive oxygen species (ROS) stress, modulation of pro-coagulant state, myocardial growth control, and its implications in metabolic control and insulin resistance. These multiple actions indicate that IL-6 is not merely a passive biomarker, but actively modulates adaptive and pathological responses to cardiovascular stress. SUMMARY: IL-6 is a multifunctional cytokine whose presence in the circulation is linked with diverse types of cardiovascular disease and is an independent risk factor for atherosclerosis. In this review, we examine the mechanisms by which IL-6 signals and its myriad effects in cardiovascular tissues that modulate the manifestations of vascular inflammation.

10.
Am J Physiol Heart Circ Physiol ; 295(6): H2436-46, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18931027

RESUMO

Endothelial nitric oxide synthase (eNOS) activation with subsequent inducible NOS (iNOS), cytosolic phospholipase A2 (cPLA2), and cyclooxygenase-2 (COX2) activation is essential to statin inhibition of myocardial infarct size (IS). In the rat, the peroxisome proliferator-activated receptor-gamma agonist pioglitazone (Pio) limits IS, upregulates and activates cPLA2 and COX2, and increases myocardial 6-keto-PGF1alpha levels without activating eNOS and iNOS. We asked whether Pio also limits IS in eNOS-/- and iNOS-/- mice. Male C57BL/6 wild-type (WT), eNOS-/-, and iNOS-/- mice received 10 mg.kg(-1).day(-1) Pio (Pio+) or water alone (Pio-) for 3 days. Mice underwent 30 min coronary artery occlusion and 4 h reperfusion, or hearts were harvested and subjected to ELISA and immunoblotting. As a result, Pio reduced IS in the WT (15.4+/-1.4% vs. 39.0+/-1.1%; P<0.001), as well as in the eNOS-/- (32.0+/-1.6% vs. 44.2+/-1.9%; P<0.001) and iNOS-/- (18.0+/-1.2% vs. 45.5+/-2.3%; P<0.001) mice. The protective effect of Pio in eNOS-/- mice was smaller than in the WT (P<0.001) and iNOS-/- (P<0.001) mice. Pio increased myocardial Ser633 and Ser1177 phosphorylated eNOS levels in the WT and iNOS-/- mice. iNOS was undetectable in all six groups. Pio increased cPLA2, COX2, and PGI2 synthase levels in the WT, as well as in the eNOS-/- and iNOS-/-, mice. Pio increased the myocardial 6-keto-PGF1alpha levels and cPLA2 and COX2 activity in the WT, eNOS-/-, and iNOS-/- mice. In conclusion, the myocardial protective effect of Pio is iNOS independent and may be only partially dependent on eNOS. Because eNOS activity decreases with age, diabetes, and advanced atherosclerosis, this effect may be relevant in a clinical setting and should be further characterized.


Assuntos
Fármacos Cardiovasculares/farmacologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/enzimologia , Óxido Nítrico Sintase Tipo III/deficiência , Óxido Nítrico Sintase Tipo II/deficiência , Tiazolidinedionas/farmacologia , 6-Cetoprostaglandina F1 alfa/metabolismo , Animais , Ciclo-Oxigenase 2/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Modelos Animais de Doenças , Immunoblotting , Oxirredutases Intramoleculares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo III/genética , Fosfolipases A2 Citosólicas/metabolismo , Fosforilação , Pioglitazona , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo
11.
Atherosclerosis ; 194(1): 125-33, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17109863

RESUMO

Angiotensin II (A-II), the major effector peptide of the renin angiotensin system potently accelerates progression of atherosclerosis. To investigate its effects on vascular inflammatory mechanisms, we elucidated vascular cytokine expression during early lesion development in A-II-infused atherosclerosis-prone LDLR-/- mice. Male LDLR-/- mice were placed on a "Western" high-fat diet for 4 weeks, followed by sham or A-II infusion for 7 weeks. Equal blood pressures and elevations in serum lipids were seen in both groups. Mice were sacrificed when significant A-II-induced plaque development was first detectable, aortae were explanted and culture media assayed for secreted cytokines. Nine cytokines were significantly induced with interleukin-6 (IL-6) being the most highly secreted. Local IL-6 production was confirmed by in situ mRNA hybridization and immunostaining, where the most abundant IL-6 was found in the aortic adventitia, with lesser production by the medial and intimal layers. Immunofluorescence colocalization showed IL-6 expression by fibroblasts and activated macrophages. Activation of downstream IL-6 signaling mediated by the Jak-STAT3 pathway was demonstrated by inducible phospho-Tyr705-STAT3 formation in the adventitia and endothelium (of IL-6+/+ mice only). These findings define cytokine profiles in the A-II infusion model and demonstrate that IL-6, produced by activated macrophages and fibroblasts in the adventitia, induces the Jak-STAT3 pathway during early A-II-induced atherosclerosis.


Assuntos
Angiotensina II/farmacologia , Aterosclerose/fisiopatologia , Interleucina-6/genética , Janus Quinases/metabolismo , Receptores de LDL/genética , Fator de Transcrição STAT3/metabolismo , Vasoconstritores/farmacologia , Animais , Aorta/fisiologia , Aterosclerose/metabolismo , Fibroblastos/fisiologia , Interleucina-6/metabolismo , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Técnicas de Cultura de Órgãos , Fosforilação/efeitos dos fármacos , RNA Mensageiro/metabolismo , Receptores de LDL/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Tirosina/metabolismo
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