interleukin-8 and Neointima

Normalized optical density (NOD) measured by optical coherence tomography represents neointimal maturity after coronary stent implantation and is correlated with morphologic information provided by both light and electron microscopy. We aimed to test the hypothesis that even second generation drug-eluting stents (DESs) are problematic in terms of neointimal maturity. We implanted bare-metal stents (BMS: n = 14), everolimus-eluting stents (EESs: n = 15) or zotarolimus-eluting stents (ZESs: n = 12) at 41 sites in 32 patients with stable coronary artery disease. OCT was performed at up to 12 months of follow-up, and the average optical density of neointima covering struts was evaluated. NOD was calculated as the optical density of stent-strut covering tissue divided by the optical density of the struts. We also measured circulating CD34+ /CD133+ /CD45low cells, and serum levels of stromal cell-derived factor (SDF)-1, interleukin (IL)-8 and matrix metalloproteinase (MMP)-9 at baseline and follow-up. NOD was lower in the EES (0.70 ± 0.06) group than in the BMS (0.76 ± 0.07, P < 0.05) and ZES (0.76 ± 0.06, P < 0.05) groups. The mean neointimal area (R = 0.33, P < 0.05) and mean neointimal thickness (R = 0.37, P < 0.05) were correlated with NOD. Although NOD was not correlated with percent changes in circulating endothelial progenitor cells, and the levels of SDF-1 and IL-8, it was negatively correlated with the change in MMP-9 level (R = - 0.51, P < 0.01). Neointimal maturity might be lower at EES sites than BMS or ZES sites. This might lead to impaired neointimal tissue growth and matrix degradation. These results suggest a specific pathophysiology after DES implantation.

Topics: Aged; Aged, 80 and over; Cardiovascular Agents; Chemokine CXCL12; Coronary Artery Disease; Coronary Vessels; Drug-Eluting Stents; Endothelial Progenitor Cells; Everolimus; Female; Humans; Interleukin-8; Male; Matrix Metalloproteinase 9; Middle Aged; Neointima; Percutaneous Coronary Intervention; Predictive Value of Tests; Prosthesis Design; Sirolimus; Time Factors; Tomography, Optical Coherence; Treatment Outcome; Vascular Remodeling

Proliferation and migration of vascular smooth muscle cells (VSMCs) can cause atherosclerosis and neointimal formation. MicroRNAs have been shown to regulate cell proliferation and phenotype transformation. We discovered abundant expression of microRNA-195 in VSMCs and conducted a series of studies to identify its function in the cardiovascular system.. MicroRNA-195 expression was initially found to be altered when VSMCs were treated with oxidized low-density lipoprotein (oxLDL) in a non-replicated microRNA array experiment. Using cellular studies, we found that microRNA-195 reduced VSMC proliferation, migration, and synthesis of IL-1β, IL-6, and IL-8. Using bioinformatics prediction and experimental studies, we showed that microRNA-195 could repress the expression of Cdc42, CCND1, and FGF1 genes. Using a rat model, we found that the microRNA-195 gene, introduced by adenovirus, substantially reduced neointimal formation in a balloon-injured carotid artery. In situ hybridization confirmed the presence of microRNA-195 in the treated arteries but not in control arteries. Immunohistochemistry experiments showed abundant Cdc42 in the neointima of treated arteries.. We showed that microRNA-195 plays a role in the cardiovascular system by inhibiting VSMC proliferation, migration, and proinflammatory biomarkers. MicroRNA-195 may have the potential to reduce neointimal formation in patients receiving stenting or angioplasty.

Topics: Adenoviridae; Animals; Carotid Arteries; Carotid Artery Injuries; cdc42 GTP-Binding Protein; Cell Movement; Cell Proliferation; Cells, Cultured; Computational Biology; Cyclin D1; Disease Models, Animal; Fibroblast Growth Factor 1; Gene Expression Profiling; Gene Expression Regulation; Genetic Therapy; Genetic Vectors; Humans; Immunohistochemistry; In Situ Hybridization; Inflammation Mediators; Interleukin-1beta; Interleukin-6; Interleukin-8; Lipoproteins, LDL; Male; MicroRNAs; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Neointima; Oligonucleotide Array Sequence Analysis; Phenotype; Rats; Rats, Sprague-Dawley; Time Factors; Transfection