RESUMO
OBJECTIVE: We aimed to determine the effect of mechanistic target of rapamycin inhibitor everolimus on abdominal aortic aneurysm within the angiotensin II (A2)-infused apolipoprotein E-deficient mouse model. APPROACH AND RESULTS: Abdominal aortic aneurysm was induced via subcutaneous infusion of A2. Flow cytometry demonstrated increased circulating and aortic C-C chemokine receptor 2 (CCR2) monocytes during A2 infusion. The number of CCR2 monocytes present within the aorta was positively correlated with suprarenal aortic diameter. Simultaneous infusion of everolimus via a second subcutaneous osmotic micropump inhibited A2-induced aortic dilatation. Using flow cytometry and Western blot analysis, decreased aortic dilatation was associated with reduced development of CCR2 bone marrow monocytes, fewer numbers of circulating CCR2 monocytes, and lower aortic CCR2 concentration. In vitro, everolimus inhibited A2-stimulated production of interferon (IFN)-γ and IFNγ-induced CCR2 expression in apolipoprotein E-deficient mouse bone marrow monocytes. Further, everolimus diminished IFNγ/lipopolysaccharide-stimulated M1 polarization in apolipoprotein E-deficient mouse bone marrow monocyte-differentiated macrophages. CONCLUSIONS: Systemic administration of everolimus limits aortic aneurysm in the A2-infused apolipoprotein E-deficient mouse model via suppressed development of bone marrow CCR2 monocytes and reduced egress of these cells into the circulation.
Assuntos
Aorta Abdominal/efeitos dos fármacos , Aneurisma da Aorta Abdominal/prevenção & controle , Apolipoproteínas E/deficiência , Monócitos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Receptores CCR2/metabolismo , Sirolimo/análogos & derivados , Serina-Treonina Quinases TOR/antagonistas & inibidores , Angiotensina II , Animais , Aorta Abdominal/enzimologia , Aorta Abdominal/imunologia , Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/enzimologia , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/imunologia , Aneurisma da Aorta Abdominal/patologia , Apolipoproteínas E/genética , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Everolimo , Citometria de Fluxo , Bombas de Infusão Implantáveis , Infusões Subcutâneas , Interferon gama/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/enzimologia , Monócitos/imunologia , Monócitos/patologia , Inibidores de Proteínas Quinases/administração & dosagem , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Sirolimo/administração & dosagem , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismoRESUMO
The effective maturation of dendritic cells (DC) is complex and highly regulated and requires the presence of a variety of signals. Tumor necrosis factor (TNF) and its receptors or innate pattern recognition receptors such as the toll-like receptors have been shown to contribute to this process. DC derived from bone marrow cells in the presence of granulocyte/macrophage colony-stimulating factor can be used as a model to ascertain the contribution of different signals to DC maturation. Analysis of DC activated by addition of the mycobacterial vaccine strain Bacillus Calmette-Guérin showed that of the effector molecules studied only interleukin-10 expression was significantly reduced in TNF-negative (B6.TNF(-/-)) DC. Another effector molecule produced by DC, inducible nitric oxide synthase, was largely unchanged.
Assuntos
Vacina BCG/metabolismo , Células Dendríticas/metabolismo , Interleucina-10/biossíntese , Receptores Tipo II do Fator de Necrose Tumoral/genética , Fator de Necrose Tumoral alfa/genética , Animais , Vacina BCG/imunologia , Medula Óssea/patologia , Diferenciação Celular/genética , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/microbiologia , Células Dendríticas/patologia , Regulação da Expressão Gênica , Interleucina-10/genética , Interleucina-10/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismoRESUMO
The generalized lymphoproliferative disorder (gld) mouse strain is characterized by severe splenomegaly/lymphadenopathy, the production of autoimmune antibodies, and the appearance of CD4/CD8-negative T cells. An additional TNF deficiency of gld/gld mice attenuates the course of the disorder through a yet-unknown mechanism. In this study, we could demonstrate that the reduced splenomegaly and lymphadenopathy in B6.gld/gld.TNF-/- mice were correlated with a decreased peripheral T cell proliferation rate and a delayed polyclonal activation. A comparative analysis of naïve T cells and memory/effector T cells showed an age-dependent difference in the T cell activation pattern in the spleen of B6.gld/gld and B6.gld/gld.TNF-/- mice. T cells from B6.gld/gld.TNF-/- spleens and lymph nodes showed significantly higher levels of CCR7 and CD62 ligand on their surface compared with B6.gld/gld mice when mice of the same age were compared. Additionally, we found an increased titer of the Th1 cytokine IFN-gamma in the serum of B6.gld/gld mice, whereas the concentration of IFN-gamma was markedly reduced in the serum of B6.gld/gld.TNF-/- mice. These findings support the hypothesis that increased T cell activation and proliferation in the presence of TNF contribute to the exacerbation of the gld syndrome.
