Our previous study suggested that heart-type fatty acid-binding protein (HFABP) levels were greatly elevated in the conditioned medium of explant culture of in-stent restenosis (ISR) tissue from diabetic minipigs compared with those of non-ISR tissue. We here verified this result in animal tissues and investigated the impact of HFABP overexpression in human aortic smooth muscle cells (hASMCs).In Western blot and real-time RT-PCR, HFABP protein and mRNA levels were significantly higher in ISR than in non-ISR tissues from minipigs, and higher in the ISR tissue from diabetic minipigs than that from nondiabetic minipigs. The mRNA microarray and cellular effects of hASMC retroviral overexpression of HFABP and vector was analyzed. Compared with vector, HFABP transduction activates multiple signaling pathways (e.g. adipokine, TGF-β, Toll-like receptor, Wnt, Hedgehog, ErbB and Notch) and promotes inflammation, growth and migration in hASMCs whereas the knockdown of HFABP by small hairpin RNA attenuates these effects.HFABP expression is significantly higher in ISR tissue than in non-ISR tissue from diabetic and nondiabetic minipigs. Overexpression of HFABP induces multiple pathway-related promotion of inflammation, growth and migration in vascular SMCs, suggesting a potential role in coronary artery ISR.
Supported rare earth double perovskite (La2MnNiO6) oxide catalysts were prepared by incipient wet impregnation method for methane catalytic combustion, and effects of the support (Al 2 O 3 , ZrO 2 and MgO) were investigated. The loaded catalysts were characterized by means of XRD, TPR, SEM techniques and their catalytic activities were tested by complete methane oxidation. Depending on the different oxide carrier (e.g. Al 2 O 3 , MgO and ZrO 2 ), catalysts have different catalytic properties, because the interaction of metal oxide-support will affect both redox property and dispersity of the active phase. The results on catalysts have shown that the dispersion on Al 2 O 3 and MgO supports had an effect to enhance the catalytic performances of the catalysts that had been treated at 1100 oC. The activity of ZrO 2 supported catalyst significantly decreases when calcination temperature at is 1100 oC. The dispersity of the active phase and the nature of the oxide carrier played an important role in the catalytic performance.
Objective— We aimed to uncover the protein changes of coronary artery in-stent restenosis (ISR) tissue in minipigs with and without streptozotocin-induced diabetes mellitus by quantitative 2-dimensional fluorescence in-gel electrophoresis (2D-DIGE), and to investigate the influences of crucial proteins identified, particularly adipocyte fatty acid binding protein (AFABP), in human arterial smooth muscle cells. Methods and Results— Sirolimus-eluting stents were implanted in the coronary arteries of 15 diabetic and 26 nondiabetic minipigs, and angiography was repeated after 6 months. The intima tissue of significant ISR and non-ISR segments in both diabetic and nondiabetic minipigs was analyzed by 2D-DIGE and MALDI-TOF/TOF mass spectrometry. AFABP level was significantly increased in ISR tissue than in non-ISR tissue in both diabetic and nondiabetic minipigs, with level being higher in diabetic ISR than in nondiabetic ISR tissue. In human arterial smooth muscle cells, overexpression of AFABP significantly altered phenotype and promoted growth and migration, with effects more prominent in high-glucose than in low-glucose medium, whereas AFABP knockdown inhibited these effects. AFABP overexpression increased reactive oxygen species production by upregulating the expression of NADPH oxidase subunits Nox1, Nox4, and P22 through multiple pathways, with elevation of downstream gene cyclin D1, matrix metalloproteinase-2, and monocyte chemoattractant protein-1. However, AFABP-induced effects were inhibited by diphenyleneiodonium, pathway inhibitors, and small interfering RNA. In addition, the supernatant from AFABP-expressing human arterial smooth muscle cells and recombinant AFABP also promoted cellular growth and migration. Conclusion— This study has demonstrated that AFABP is significantly increased in coronary artery ISR segments of both diabetic and nondiabetic minipigs. Increased AFABP expression and secretory AFABP of human arterial smooth muscle cells promote growth and migration via reactive oxygen species-mediated activation.
In a previous study, we established diabetic and nondiabetic minipig models with coronary artery in-stent restenosis (ISR). Mass spectrometry showed that high-mobility group box (HMGB) 2 level was higher in ISR than in non-ISR tissue from diabetic minipigs. We here investigated whether serum HMGB2 levels were related to ISR in coronary artery disease patients. The effect of HMGB2 was evaluated in mice with femoral artery wire injury and in human aortic smooth muscle cells.From 2513 patients undergoing coronary artery intervention and follow-up angiography at ≈1 year, 262 patients were diagnosed with ISR, and 298 patients with no ISR were randomly included as controls. Serum HMGB2 levels were significantly higher in patients with ISR than in those without ISR and were associated with ISR severity. Multivariable logistic regression analysis showed that HMGB2 level was independently associated with ISR. In experiments, HMGB2 expression was increased in vascular tissue after injury. Perivascular HMGB2 administration promoted injury-induced neointimal hyperplasia in C57Bl/6 mice compared with in the control, whereas such pathophysiological features were attenuated in Hmgb2-/- mice. Mechanistically, HMGB2 enhanced neointimal hyperplasia in mice and proliferation and migration in human aortic smooth muscle cells by inducing reactive oxygen species through increased p47phox phosphorylation. Knocking down p47phox, however, inhibited HMGB2-induced effects in human aortic smooth muscle cells. Finally, HMGB2-induced effects were significantly declined in receptor of advanced glycation end products knockdown or deficient cells, but not in Toll-like receptor 4 knockdown or deficient cells.Serum HMGB2 levels were associated with ISR in patients. HMGB2 promoted neointimal hyperplasia in mice with arterial wire injury through reactive oxygen species activation.