Author:

Keywords:

Science & Technology, Life Sciences & Biomedicine, Peripheral Vascular Disease, Cardiovascular System & Cardiology, ANGIOTENSIN-II, OXIDATIVE STRESS, HEART-FAILURE, NADPH OXIDASE, ENDOTHELIAL DYSFUNCTION, MYOCARDIAL-INFARCTION, PULMONARY-FIBROSIS, HYPERTENSIVE-RATS, SOD EXPRESSION, CU/ZN-SOD, Adjuvants, Immunologic, Angiotensin II, Animals, Cells, Cultured, Collagen, Cyclic N-Oxides, Ditiocarb, Drug Synergism, Fibroblasts, Gene Expression, Male, Myocardium, Protein Synthesis Inhibitors, RNA, Rats, Rats, Wistar, Reactive Oxygen Species, Spin Labels, Superoxide Dismutase, Vasoconstrictor Agents, 1103 Clinical Sciences, Cardiovascular System & Hematology, 3201 Cardiovascular medicine and haematology, 3202 Clinical sciences

Abstract:

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: These data suggest a vital role of SOD and the formed ROS in the accumulation of collagen in cardiac fibroblasts.