Cathepsin L derived from skeletal muscle cells transfected with bFGF promotes endothelial cell migration

Gene transfer of basic fibroblast growth factor (bFGF) has been shown to induce significant endothelial migration and angiogenesis in ischemic disease models. Here, we investigate what factors are secreted from skeletal muscle cells (SkMCs) transfected with bFGF gene and whether they participate in endothelial cell migration. We constructed replication-defective adenovirus vectors containing the human bFGF gene (Ad/bFGF) or a control LacZ gene (Ad/LacZ) and obtained conditioned media, bFGF-CM and LacZ-CM, from SkMCs infected by Ad/bFGF or Ad/LacZ, respectively. Cell migration significantly increased in HUVECs incubated with bFGF-CM compared to cells incubated with LacZ-CM. Interestingly, HUVEC migration in response to bFGF-CM was only partially blocked by the addition of bFGF-neutralizing antibody, suggesting that bFGF-CM contains other factors that stimulate endothelial cell migration. Several proteins, matrix metalloproteinase-1 (MMP-1), plasminogen activator inhibitor-1 (PAI-1), and cathepsin L, increased in bFGF-CM compared to LacZ-CM; based on 1-dimensional gel electrophoresis and mass spectrometry. Their increased mRNA and protein levels were confirmed by RT-PCR and immunoblot analysis. The recombinant human bFGF protein induced MMP-1, PAI-1, and cathepsin L expression in SkMCs. Endothelial cell migration was reduced in groups treated with bFGF-CM containing neutralizing antibodies against MMP-1 or PAI-1. In particular, HUVECs treated with bFGF-CM containing cell-impermeable cathepsin L inhibitor showed the most significant decrease in cell migration. Cathepsin L protein directly promotes endothelial cell migration through the JNK pathway. These results indicate that cathepsin L released from SkMCs transfected with the bFGF gene can promote endothelial cell migration.

Renin-Angiotensin-Aldosterone System (RAAS) Gene Polymorphism as a Risk Factor of Coronary In-Stent Restenosis

Intimal proliferation is a main cause of in-stent restenosis. Over-excretion of angiotensin I converting enzyme (ACE) and aldosterone is reported to stimulate intimal hyperplasia and the genetic effect of these molecules may alter the process of in-stent restenosis. We hypothesized that the genetic polymorphisms that alter the expression of genes such as ACE I/D, CYP11B2-344C/T, and AGT M235T can affect in-stent restenosis. We analyzed the angiographic and clinical data of 238 patients (272 stents) who underwent coronary stenting and follow-up angiography, and analyzed the genotypes of ACE I/D, CYP11B2-344T/C, and AGT M235T. There was no significant difference in age, sex, or lipid profiles between the patent and restenosis groups. Diabetes mellitus was more frequent in the binary restenosis group. Quantitative computer-assisted angiographic (QCA) analysis revealed that the risk of in-stent restenosis increased with lesion length and was inversely proportional to post- stenting minimal luminal diameter (MLD) and reference diameter. There was no difference in the frequency of binary restenosis between genotypes in each of the three genes. However, follow-up MLD was significantly smaller in the ACE DD genotype than in the ACE II or ID genotypes. Defining restenosis as MLD 2 mm, the restenosis rate was significantly higher in the ACE DD genotype than in the ACE II or ID genotypes. There was no significant synergistic effect between the three gene polymorphisms. In conclusion, while the ACE I/D polymor phism promoted the progress of in-stent restenosis and was of clinical significance, the other potential variables examined did not correlate with in-stent restenosis.

The Effects of an Aldosterone Synthase (CYP11B2) Gene Polymorphism on the Risk of Myocardial Infarction

BACKGROUND AND OBJECTIVES: Several polymorphisms of the renin-angiotensin-aldosterone system have been found to have pleiotropic effects on cardiovascular diseases. Polymorphism of the aldosterone synthase gene (CYP11B2), which may influence plasma aldosterone levels, has been reported to cause systemic hypertension, influence the left ventricular diameter and mass, and decrease baroreflex sensitivity of the cardiovascular system. Through these mechanisms, it is thought to increase the risk of myocardial infarction (MI). Our study was designed to elucidate whether polymorphism of CYP11B2 increased the risk of MI. SUBJECTS AND METHODS: We analyzed the genotypes of CYP11B2 and the classic risk factors of MI in 188 MI patients and 320 control subjects without history of MI. RESULTS: There was no significant difference in the distribution of genotypes between the patient and control groups. Adjusting for the classical risk factors, multiple logistic regression analysis showed no significant effect of CYP11B2 gene polymorphism on the development of MI. However, the presence of the -344C allele is associated with a markedly increased MI risk conferred by classic risk factors including hypertension, smoking, and male sex. In particular, hypertension was not a significant risk factor as compared with non-hypertensive patients in subjects without -344C, but the relative risk was increased to 2.40 (95% CI:1.05-5.51, p<0.05) with - 344C. The relative risks of smoking and male sex were also increased with the presence of the - 344C allele. CONCLUSION: CYP11B2 polymorphism is not an independent risk factor of MI, although hypertension, smoking, and male sex are more potent risk factors for MI in Koreans who possess the - 344C allele.