Lijnen Paul, Petrov Victor, van Pelt Jos, Fagard Robert
Hypertension and Cardiovascular Rehabilitation Unit, Department of Cardiovascular Diseases, Katholieke Universiteit Leuven, Leuven, Belgium.
Am J Hypertens. 2008 Oct;21(10):1129-36. doi: 10.1038/ajh.2008.242. Epub 2008 Aug 28.
The aim of this study was to determine whether inhibition of superoxide dismutase (SOD) with diethyldithiocarbamic acid (DETC) could affect the collagen production, the mRNA and protein expression of collagen types I and III, and fibronectin in control and angiotensin II (ANG II)-treated cardiac fibroblasts. Its effect was compared with the SOD mimetics tempol and EUK-8 and with polyethyleneglycol (PEG)-SOD.
Cardiac fibroblasts were cultured to confluence, incubated in serum-free Dulbecco's modified Eagle's medium for 24 h, preincubated with(out) the tested inhibitors for 1 h and further incubated with(out) ANG II (1 micromol/l) for 24 h.
DETC dose-dependently inhibited the activity of CuZn-SOD in cardiac fibroblasts. Superoxide anion production was increased by DETC and decreased by tempol in control and ANG II-treated fibroblasts. DETC also reduced the intracellular generation of reactive oxygen species (ROS) (such as H2O2, hydroxyl radicals, hydroperoxides) in control and ANG II-treated fibroblasts, whereas tempol reduced the ROS production only in ANG II-treated fibroblasts. ANG II and DETC stimulated the collagen production and the collagen I and fibronectin content in fibroblasts. The SOD mimetics tempol and EUK-8 as well as PEG-SOD reduced the collagen production. ANG II and DETC stimulated the tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 levels, whereas tempol decreased the TIMP-2 content in control and ANG II-treated fibroblasts. Matrix metalloproteinase (MMP)-1 level was reduced by ANG II and DETC and increased by tempol.
These data suggest a vital role of SOD and the formed ROS in the accumulation of collagen in cardiac fibroblasts.
本研究旨在确定用二乙基二硫代氨基甲酸盐（DETC）抑制超氧化物歧化酶（SOD）是否会影响对照及血管紧张素II（ANG II）处理的心脏成纤维细胞中的胶原蛋白生成、I型和III型胶原蛋白的mRNA及蛋白表达以及纤连蛋白。将其效果与SOD模拟物tempol和EUK - 8以及聚乙二醇（PEG）- SOD进行比较。
将心脏成纤维细胞培养至汇合状态，在无血清的杜尔贝科改良伊格尔培养基中孵育24小时，用（不用）受试抑制剂预孵育1小时，然后用（不用）ANG II（1微摩尔/升）进一步孵育24小时。
DETC剂量依赖性地抑制心脏成纤维细胞中铜锌超氧化物歧化酶的活性。在对照及ANG II处理的成纤维细胞中，DETC使超氧阴离子生成增加，而tempol使其减少。DETC还降低了对照及ANG II处理的成纤维细胞中细胞内活性氧（ROS）（如过氧化氢、羟基自由基、氢过氧化物）的生成，而tempol仅在ANG II处理的成纤维细胞中降低了ROS生成。ANG II和DETC刺激了成纤维细胞中的胶原蛋白生成以及I型胶原蛋白和纤连蛋白含量。SOD模拟物tempol和EUK - 8以及PEG - SOD减少了胶原蛋白生成。ANG II和DETC刺激了金属蛋白酶组织抑制剂 - 1（TIMP - 1）和TIMP - 2水平，而tempol降低了对照及ANG II处理的成纤维细胞中TIMP - 2的含量。血管紧张素II和DETC降低了基质金属蛋白酶（MMP）- 1水平，而tempol使其升高。
这些数据表明SOD及生成的ROS在心脏成纤维细胞胶原蛋白积累中起重要作用。
