title: Interleukin-10 inhibits the in vivo and in vitro adverse effects of TNF-alpha on the endothelium of murine aorta.
abstract: TNF-α is a proinflammatory cytokine and is an important mediator of maternal endothelial dysfunction leading to preeclampsia. In this study, we tested whether IL-10 protects against TNF-α-induced endothelial dysfunction in murine aorta. In in vitro experiments, aortic rings of C57BL/6 female mice were incubated in Dulbecco's modified Eagle's medium in the presence of either vehicle (distilled H(2)O), TNF-α (4 nmol/l), or recombinant mouse IL-10 (300 ng/ml) or in the presence of both TNF-α and IL-10 for 22 h at 37°C. In in vivo experiments C57BL6/IL-10 knockout female mice were treated with saline or TNF-α (220 ng·kg(-1)·day(-1)) for 14 days. Aortic rings were isolated from in vitro and in vivo experiments and mounted in a wire myograph (Danish Myotech) and stretched to a tension of 5 mN. Endothelium-dependent relaxation was assessed by constructing cumulative concentration-response curves to acetylcholine (ACh, 0.001-10 μmol/l) during phenylephrine (10 μmol/l)-induced contraction. As a result, overnight exposure of aortic rings to TNF-α resulted in significant blunted maximal relaxing responses (E(max)) to ACh compared with untreated rings (22 ± 4 vs. 82 ± 3%, respectively). IL-10 knockout mice treated with TNF-α showed significant impairment in ACh responses (E(max)) compared with C57BL/6 mice treated with TNF-α (51 ± 3 vs. 72 ± 3%, respectively). Western blot analysis showed that endothelial nitric oxide synthase (eNOS) expression was reduced by TNF-α in in vitro and in vivo experiments, whereas IL-10 restored the eNOS expression. In conclusion, the anti-inflammatory cytokine IL-10 prevents impairment in endothelium-dependent vasorelaxation caused by TNF-α by protecting eNOS expression.
authors.affiliation: Department of Physiology, Medical College of Georgia, Augusta, GA 30912, USA. szemse@students.mcg.edu
authors.forename: Saiprasad M
authors.initials: SM
authors.lastname: Zemse
authors.forename: Chin Wei
authors.initials: CW
authors.lastname: Chiao
authors.forename: Rob H P
authors.initials: RH
authors.lastname: Hilgers
authors.forename: R Clinton
authors.initials: RC
authors.lastname: Webb
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000187:drug effects* / Q000378:metabolism* / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism* / Q000503:physiopathology; D005260:Female; D051550:I-kappa B Kinase / Q000378:metabolism; D016753:Interleukin-10 / Q000172:deficiency* / Q000378:metabolism / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D023421:Models, Animal; D016328:NF-kappa B / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D010656:Phenylephrine / Q000494:pharmacology; D010766:Phosphorylation; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000494:pharmacology*; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D016753:Interleukin-10; D010656:Phenylephrine; D052250:Nitric Oxide Synthase Type III; D051550:I-kappa B Kinase; D000109:Acetylcholine