Lowering of dietary advanced glycation endproducts (AGE) reduces neointimal formation after arterial injury in genetically hypercholesterolemic mice

Restenosis remains a major cause of morbidity and mortality after coronary angioplasty. Injury-induced inflammation, thrombosis, smooth muscle cell (SMC) proliferation, and neointimal formation contribute to restenosis. These events are linked to circulating glucose-derived advanced gycation endproducts (AGE), known to promote cell proliferation, lipid glycoxidation and oxidant stress. This study evaluates the association between dietary AGE content and neointimal formation after arterial injury in genetically hypercholesterolemic mice. Male, 12-week-old, apolipoprotein E-deficient (apoE(-/-)) mice were randomly assigned to receive either a high AGE diet (HAD; AGE=15000 U/mg), or a similar diet with ten-fold lower AGE (LAD; AGE=1500 U/mg). These mice underwent femoral artery injury 1 week later, and were maintained on their diets for an additional 4 weeks. At 4 weeks after injury, significant decrease in neointimal formation was noted in LAD-fed mice. Neointimal area, intima/media ratio, and stenotic luminal area (LA) were less pronounced in the LAD group than the HAD group (P<0.05). These quantitative differences were associated with a marked reduction ( approximately 56%) of macrophages in the neointimal lesions, as well as an obvious reduction of SMC content of LAD-fed mice. The reduction of neointimal formation in the LAD mice correlated with a approximately 40% decrease in circulating AGE levels (P<0.0005). Immunohistochemistry also showed a reduced ( approximately 1.5-fold) deposition of AGE in the endothelia, SMC, and macrophages in neointimal lesions of LAD-fed mice. These results represent the first evidence in vivo for a causal relationship between dietary AGE and the vessel wall response to acute injury, suggesting a significant potential for dietary AGE restriction in the prevention of restenosis after angioplasty.     

Sulindac inhibits neointimal formation after arterial injury in wild-type and apolipoprotein E-deficient mice

Neointimal hyperplasia is a critical component of restenosis, a major complication of angioplasty and related therapeutic procedures. We studied the effects of hyperlipidemia and the nonsteroidal anti-inflammatory drugs, aspirin (acetyl-salicylic acid; ASA), and sulindac, on neointimal formation in a mouse femoral arterial injury model. At 2 months of age, normolipidemic, wild-type (WT), and hyperlipidemic, apolipoprotein E-deficient (apoE-/-) mice were divided into three treatment groups: Western-type diet (WD), WD + ASA (200 mg/kg food), and WD + sulindac (300 mg/kg food). After 1 week, mice underwent arterial injury and treatments were maintained for 4 weeks. Histomorphometry of the injured arteries showed striking effects of plasma cholesterol levels and drug treatment on neointimal hyperplasia. In the WD or WD + ASA groups, apoE-/- mice had twice the neointimal area than WT mice ( approximately 30,000 vs. 13,000 microm(2) per section; P < 0.0001). Compared with ASA or WD alone, sulindac treatment resulted in approximately 70% (P = 0.0001) and 50% (P = 0.01) reductions in the neointimal area in apoE-/- and WT mice, respectively. ASA, at a dose sufficient to inhibit platelet aggregation, did not affect neointimal formation in mice of either genotype. Evidence of macrophages was noted in the lesions of apoE-/- mice in the WD and WD + ASA groups, but remarkably, none was detectable with sulindac treatment, despite hyperlipidemia, suggesting early steps in the response to injury were abrogated. These results demonstrate sulindac reduces neointimal formation in both normolipidemic and hyperlipidemic settings and raise the possibility that similar benefits may be obtained in patients undergoing angioplasty and related procedures.     

Local delivery of green tea catechins inhibits neointimal formation in the rat carotid artery injury model

It has been shown that green tea catechins (GTC) suppress proliferation of vascular smooth muscle cells (VSMCs) and that epigallocatechin-3-gallate (EGCG), which is a major constituent of GTC, selectively inhibits the platelet-derived growth factor-BB (PDGF-BB)-induced intracellular signaling transduction pathway. Vascular smooth muscle cell proliferation is one of major mechanisms of restenosis following percutaneous coronary intervention. This study tested whether GTC can inhibit VSMC proliferation and prevent neointimal formation in a rat carotid artery injury model. Vascular smooth muscle cell proliferation inhibition was analyzed with [³H]thymidine incorporation. Green tea catechins were applied to the endothelium-denuded carotid arteries of rats for 20min. Angiography and morphometric analysis was performed after 2 weeks. Green tea catechins decreased [³H]thymidine incorporation stimulated with PDGF-BB dose dependently. In the absence of PDGF-BB, the decrement of [³H]thymidine incorporation was evident above a concentration of 10µg/ml of GTC. Carotid arteriographic evaluation showed that the minimum luminal diameter in the GTC-treated group (n = 12) was 5.9 ± 1.6 arbitrary units (a.u.) and was significantly larger than in the control group (4.3 ± 1.4 a.u., n = 10) (P < 0.05). The GTC-treated group also showed a significant reduction in neointimal formation compared with the control group (0.29 ± 0.11 vs 0.42 ± 0.10mm², P < 0.05). To identify the active ingredients, we performed a similar experiment using EGCG. The effects of EGCG were similar to those of GTC. Green tea catechins effectively inhibited VSMC proliferation. Neointimal formation was prevented in the rat carotid artery injury model by local delivery of GTC. As EGCG showed similar effects, it may be one of the major constituents of GTC having these effects.     

腺病毒介导的人p27kip1基因转染对球囊损伤后兔颈动脉新生内膜增生的抑制作用

目的 研究腺病毒介导的p27kip1基因及其蛋白产物高表达对球囊损伤后兔颈动脉新生内膜增生的抑制作用。方法 建立兔颈动脉球囊损伤模型,将LacZ重组腺病毒（AdLacZ）和人p27kipl重组腺病毒（Adhp27kipl）在体内分别转染损伤动脉节段,以Western　blot、x-gal染色、HE染色、兔疫组化及计算机图像处理方法观察转染动脉节段中外源性p27kipl蛋白表达及其对新生内膜增生的影响。结果 与AdLacZ转染组及未转染组比较,Adhp27kip1转染的动脉节段内p27kip1蛋白呈高表达,表达高峰在7～14 d,持续4周以上;转染4周后未转染组、AdLacZ转染组及Adhp27kip1转染组的新生内膜面积分别为1.106mm2、0.988mm2及0.278mm2;管腔狭窄率分别为87.07％、65.40％及32.14％。结论 外源性p27kip1基因及其蛋白产物在损伤动脉节段内高表达可显著抑制新生内膜增生及管腔狭窄。     

Alpha-lipoic acid inhibits fractalkine expression and prevents neointimal hyperplasia after balloon injury in rat carotid artery

Vascular inflammation induced by the proinflammatory cytokine/NF-kappaB pathway is one of the key mechanisms in the development of neointimal hyperplasia. Accumulating evidence suggests that a recently identified chemokine, fractalkine, is involved in arterial inflammation and atherogenesis. However, no study has examined the expression of neointimal fractalkine and the effects of pharmacological agents on this process. The purposes of this study were to measure neointimal fractalkine expression in the rat carotid artery following balloon injury and to determine if alpha-lipoic acid (ALA) inhibits fractalkine expression and neointimal hyperplasia. Balloon injury of the rat carotid artery induced fractalkine expression in the medial as well as neointimal regions. ALA inhibited this expression and consequently prevented neoinitmal hyperplasia in a balloon-injured rat carotid artery. Additionally, ALA inhibited TNF-alpha-stimulated fractalkine expression in cultured vascular smooth muscle cells (VSMCs), a process which is mediated through the NF-kappaB pathway. In addition to fractalkine, ALA successfully inhibited TNF-alpha-stimulated expression of vascular cell adhesion molecule-1 and monocyte chemotactic protein-1 in cultured VSMCs. These data suggest that the cytokine-fractalkine system is involved in the pathogenesis of restenosis. The present study supports the possibility that ALA, which inhibits the NF-kappaB/fractalkine pathway, may be used to prevent neointimal hyperplasia after angioplasty or stenting.     

Prostacyclin synthase gene transfer accelerates reendothelialization and inhibits neointimal formation in rat carotid arteries after balloon injury

Prostacyclin (PGI2), a metabolite of arachidonic acid, has the vasoprotective effects of vasodilation, anti-platelet aggregation, and inhibition of smooth muscle cell proliferation. We hypothesized that an overexpression of endogenous PGI2 may accelerate the recovery from endothelial damage and inhibit neointimal formation in the injured artery. To test this hypothesis, we investigated in vivo transfer of the PGI2 synthase (PCS) gene into balloon-injured rat carotid arteries by a nonviral lipotransfection method. Seven days after transfection, a significant regeneration of endothelium was observed in the arteries transfected with a plasmid carrying the rat PCS gene (pCMV-PCS), but little regeneration was seen in those with the control plasmid carrying the lacZ gene (pCMV-lacZ) (percent luminal circumference lined by newly regenerated endothelium: 87. 1+/-6.9% in pCMV-PCS-transfected vessels and 6.9+/-0.2% in pCMV-lacZ vessels, P<0.001). BrdU staining of arterial segments demonstrated a significantly lower incorporation in pCMV-PCS-transfected vessels (7. 5+/-0.3% positive nuclei in vessel cells) than in pCMV-lacZ (50. 7+/-9.6%, P<0.01). Moreover, 2 weeks after transfection, the PCS gene transfer resulted in a significant inhibition of neointimal formation (88% reduction in ratio of intima/media areas), whereas medial area was similar among the groups. Arterial segments transfected with pCMV-PCS produced significantly higher levels of 6-keto-PGF1alpha, the main metabolite of PGI2, compared with the segments transfected with pCMV-lacZ (10.2+/-0.55 and 2.1+/-0.32 ng/mg tissue for pCMV-PCS and pCMV-placZ, P<0.001). In conclusion, this study demonstrated that an in vivo PCS gene transfer increased the production of PGI2 and markedly inhibited neointimal formation with accelerated reendothelialization in rat carotid arteries after balloon injury.     

Neuregulin-1 attenuates neointimal formation following vascular injury and inhibits the proliferation of vascular smooth muscle cells

Neuregulin-1 (NRG-1) is expressed in vascular endothelial cells, and its receptors are localized to the underlying smooth muscle cells. However, the role of NRG-1 in vascular function and injury is largely unknown. First, the expression of NRG-1 and its receptors (erbB receptors) was analyzed after balloon injury to the rat carotid artery. NRG-1 and erbB expression levels were low in uninjured vessels; however, NRG-1 and erbB4 were upregulated following injury. We then examined the effect of NRG-1 on neointimal formation following balloon injury. NRG-1 was administered by tail-vein injection prior to injury and every 2 days following injury. Two weeks after injury, NRG-1-treated animals demonstrated a 50% reduction in lesion size compared with controls receiving the vehicle. To examine possible mechanisms for NRG-1 action, we examined its effects on vascular smooth muscle cell (VSMC) function. Rat VSMC cultures were pretreated with NRG-1 for 24 h and then stimulated with platelet-derived growth factor. NRG-1 significantly decreased platelet-derived growth factor-stimulated VSMC proliferation and migration. These findings suggest that NRG-1 may be a novel therapeutic candidate for the treatment of restenosis and atherosclerosis.     

Plasma soluble adhesion molecules; intercellular adhesion molecule-1, vascular cell adhesion molecule-1 and E-selectin levels in patients with isolated coronary artery ectasia

Plasma soluble adhesion molecules, intercellular adhesion molecule-1 (ICAM)-1, vascular cell adhesion molecule-1 (VCAM-1) and E-selectin leves of patients with isolated coronary artery ectasia (CAE), patients with obstructive coronary artery disease without CAE and subjects with angiographically normal coronary arteries were evaluated. Patients with isolated CAE were detected to have significantly higher levels of plasma soluble ICAM-1, VCAM-1 and E-selectin in comparison with patients with obstructive coronary artery disease without CAE (ICAM, 673 +/- 153 versus 381 +/- 106, respectively, P < 0.001; VCAM-1, 2366 +/- 925 versus 1136 +/- 208, respectively, P < 0.001; E-selectin, 74 +/- 21 versus 61 +/- 18, respectively, P = 0.01) and subjects with normal coronary arteries (ICAM-1, 673 +/- 153 versus 303 +/- 131, respectively, P < 0.001; VCAM-1, 2366 +/- 925 versus 729 +/- 231, respectively, P < 0.001; E-selectin, 74 +/- 21 versus 49 +/- 9, respectively, P < 0.001), suggesting the presence of a more severe and extensive chronic inflammation in the coronary circulation in patients with isolated CAE. BACKGROUND: The common coexistence of coronary artery ectasia (CAE) with coronary artery disease (CAD) suggests that it may be a variant of CAD. However, it is not clear why some patients with obstructive CAD develop CAE whereas most do not. Inflammation has been reported to be a major contributing factor to both obstructive and aneurysmatic vascular disorders and therefore, in the present study, the plasma soluble adhesion molecules, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin levels in isolated CAE were investigated. METHODS: The study population consisted of three groups: the first consisted of 32 patients with isolated CAE without stenotic lesion; the second of 32 patients with obstructive CAD without CAE; and the third group of 30 control subjects with normal coronary arteries. Coronary diameters were measured as the maximum diameter of the ectasic segment by use of a computerized quantitative coronary angiography analysis system. According to the angiographic definition used in the Coronary Artery Surgery Study, a vessel is considered to be ectasic when its diameter is > or =1.5 times that of the adjacent normal segment in segmental ectasia. Plasma soluble ICAM-1, VCAM-1 and E-selectin levels were measured in all patients and control subjects using commercially available enzyme-linked immunosorbent assay kits. RESULTS: Patients with isolated CAE were found to have significantly higher levels of plasma soluble ICAM-1, VCAM-1, and E-selectin in comparison with patients with obstructive CAD without CAE (ICAM, 673 +/- 153 versus 381 +/- 106, respectively; P < 0.001; VCAM-1, 2366 +/- 925 versus 1136 +/- 208, respectively; P < 0.001; E-selectin, 74 +/- 21 versus 61+/-18, respectively; P = 0.01) and control subjects with normal coronary arteries (ICAM-1, 673 +/- 153 versus 303 +/- 131, respectively;, P < 0.001; VCAM-1, 2366 +/- 925 versus 729 +/- 231, respectively; P < 0.001; E-selectin, 74 +/- 21 versus 49 +/- 9, respectively; P < 0.001). In addition, we detected statistically significant positive correlation between the total length of ectasic segments and the levels of plasma soluble ICAM-1 (r = 0.625; P < 0.001), VCAM-1 (r = 0.548; P = 0.001) and E-selectin (r = 0.390; P = 0.027). Multivariate logistic regression analysis revealed a significant independent relation between isolated CAE and ICAM-1 [odds ratio (OR) = 1.023; 95% confidence interval (CI) = 1.0048-1.0414; P = 0.0129] and VCAM-1 (OR = 1.0057; 95% CI = 1.0007-1.0106; P = 0.0240). CONCLUSIONS: We have shown that patients with isolated CAE have raised levels of plasma soluble ICAM-1, VCAM-1 and E-selectin in comparison with patients with obstructive CAD without CAE and control subjects with normal coronary arteries, suggesting the presence of a more severe and extensive chronic inflammation in the coronary circulation in these patients.     

胃肿瘤患者循环可溶性细胞间粘附分子-1和血管细胞粘附分子-1

AIM To elucidate the biological and clinical significance of sICAM-1 and sVCAM-1 in patients with gastric cancer.METHODS The serum levels of soluble ICAM-1 and VCAM-1 were measured with sandwith enzyme immunoassay.RESULTS In gastric cancer patients, soluble ICAM-1 and VCAM-1 concentrations were significantly elevated in comparision with those of healthy subjects (289.23μg/L±32.69μg/L vs 190.44μ/L±35.92μg/L,1430.88μg/L±421.71μg/L vs 727.24μg/L±157.68μg/L, respectively, P＜0.01). The increment in serum sICAM-1 and sVCAM-1 concentrations correlated well with the staging of gastric cancer. The serum levels of sICAM-1 and sVCAM-1 in patients of Ⅲ-Ⅳ stages were higher than those of Ⅰ-Ⅱ stages (346.60μg/L±92.10μg/L vs 257.54μg/L±32.77μg/L, 1800.60μg/L±510.76μg/L vs 1262.81μg/L±236.73μg/L). The levels of sICAM-1 and sVCAM-1 were correlated significantly (r=0.49,P＜0.01). The sICAM-1 and sVCAM-1 levels correlated positively with alkaline phophatase (r=0.63,0.71,P＜0.001) and white cell count (r=0.52,0.43, P＜0.01); but correlated negatively with serum albumin (r=-0.41, -0.49, P＜0.01).CONCLUSION The measurement of circulating ICAM-1 and VCAM-1 may bring additional prognostic information for patients with gastric cancer in varying stages.INTRODUCTIONTumor growth and metastasis involves a variety of cell-cell and cell-extracellular matrix interactions mediated by cell adhesion molecules. Currently, a number of cell adhesion molecules, such as intercellular adhesion molecules-1 (ICAM-1), vascular cell adhesion molecules-1 (VCAM-1), etc. have been found.ICAM-1 and VCAM-1 are members of the immunoglobulin supergene family which are cytokine-induced glycoproteins (IL-1, TNFα and IFNγ). Both of them have five or seven extracellular immunoglobulin-like domains, a single transmembranous domain and a short cytoplasmic tail[1,2]. The natural ligand of ICAM-1 or VCAM-1 is LFA-1 (CD11a) and Mac-1 (CD11b) or VLA-4, respectively[3]. ICAM-1 is a widely distributed protein on a variety of tissues, and can be detected in many cells such as macrophage, T- and B-cells, or fibroblasts, endothelial and epithelial cells. VCAM-1 is also a widely distributed protein and is constitutively expressed on tissue macrophage, dentritic cells in lymphoid tissue and skin, as well as on bone marrow fibroblasts and epithelial cells. Expression of VCAM-1 is inducible on vascular endothelial cells under pathological conditions[4].Recently, soluble forms of several adhesion molecules including ICAM-1 and VCAM-1 were found in serum of normal donors[5]. Abnormally high levels of them have been described in some solid malignant tumors, leukemia, autoimmune disease, infectious disease, etc.The present study was carried out to measure the circulating levels of sICAM-1 and sVCAM-1 in gastric cancer before treatment was given and to study their correlation with clinical, histological and routine laboratory parameters.     

Expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in the pig coronary artery injury model: comparison of plain old balloon angioplasty and stent implantation

OBJECTIVES: Restenosis after coronary intervention usually occurs due to coronary remodeling or neointimal formation, but inflammation is also important especially after stent implantation. Adhesion molecules are important in the recruitment of inflammatory cells into the neointima and in the phenotypical changes of vascular smooth muscle cells. To examine the role of adhesion molecules in the pathogenesis of restenosis, immunohistochemical expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was investigated in the pig coronary injury model. METHODS: Left anterior descending coronary arteries of pigs were injured using a balloon. Two weeks after the injury, balloon injury was performed again in the balloon group and a Palmaz-Schatz stent was implanted in the stent group. Pigs were sacrificed at 1, 2 and 4 weeks. Immunohistochemical analysis was performed using ICAM-1, VCAM-1, macrophage and alpha-smooth muscle actin antibodies. RESULTS: In non-injured vessels, weak immunoreactivities of ICAM-1 and VCAM-1 were observed in the endothelium and media. In injured sites, ICAM-1 and VCAM-1 were found in the inflammatory cells and smooth muscle cells in the neointima from 1 week, and strong immunoreactivities were seen around the strut in the stent group. Although the immunoreactivities peaked at 2 weeks in the balloon group, strong immunoreactivities were still seen at 4 weeks in the stent group. Regenerated endothelial cells were positive for both antibodies from 2 weeks. CONCLUSIONS: The expression of ICAM-1 and VCAM-1 lasted longer in the stent group than in the balloon group, suggesting the occurrence of late restenosis after stent implantation. Control of the inflammatory response including adhesion molecules is essential for further reduction of restenosis after stent implantation.     

Levels of serum vascular cell adhesion molecule-1 in measles

While the levels of serum vascular cell adhesion molecule-1 (VCAM-1) have been investigated in many diseases, they have not, to our knowledge, been studied in patients with measles. Serum VCAM-1 and creatinine levels were determined in six adolescent and adult Japanese patients with measles in the acute febrile phase and defervescent afebrile phase. Serum VCAM-1 levels were significantly higher in the acute febrile phase than in the convalescent afebrile phase, but no significant difference between the serum creatinine levels was shown in the two phases. Our study revealed that the high serum VCAM-1 level in the acute febrile phase later decreased in the afebrile convalescent phase. The measurement of circulating VCAM-1 may be useful for the assessment of convalescence in patients with measles.     

男性冠心病患者雄激素与颈动脉内膜和中膜厚度及血管细胞黏附因子-1的关系

目的探讨男性冠状动脉粥样硬化性心脏病(冠心病)患者体内雄激素水平与反映内皮功能异常的指标颈动脉内膜、中膜厚度(IMT)、血管细胞黏附因子-1(VCAM-1)的关系,观察雄激素减轻动脉粥样硬化的程度。方法比较51例男性冠心病患者与55例对照者的年龄、体质量、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、三酰甘油(TG)、吸烟、空腹血糖、血压、血清游离睾酮水平(FT)、VCAM-1及IMT,分析冠心病危险因素如年龄、体质量、TC、LDL-C、HDL-C、TG、吸烟、空腹血糖、血压及FT与VCAM-1、IMT的相关性。结果冠心病组的年龄、血压、吸烟史、空腹血糖、HDL-C与对照组比较,差异无统计学意义(P>0．05);体质量为(78．1±5．7)kg,大于对照组的(73．6±4．8)kg,P<0．01;TC高于对照组[(4．99±0．88)mmol／L和(4．52±0．65)mmol／L,P<0.01];LDL-C高于对照组[(3．35±0．63)mmol／L和(2．94±0．55)mmol／L,P<0．01];TG高于对照组[(2．35±0．92)mmol／L和(1．87±0．61)mmol／L,P<0．01];FT低于对照组[(13．2±3.6)×10-9g／L和(16．6±5．1)×10-9g／L,P<0．01];IMT高于对照组[(1．11±0．24) mm和(0．96±0．22)mm,P<0．01];VCAM-1含量高于对照组[(372．7±111．8)×10-6g／L和(208．2±72．5)×10-6g／L,P<0.01]。多元逐步回归分析显示FT与IMT、VCAM-1分别呈负相关(r=-0.358,r=-0.547,均为P<0．01)。结论男性冠心病患者FT水平与反映内皮功能异常的指标IMT、VCAM-1呈负相关。