OBJECTIVETo investigate Bcl-2/Bax gene expression in different types of carotid plaque, and examine the relationship between gene expression and atherosclerotic plaque instability and the main cause of brain ischemic events.

METHODSTotally 42 human carotid plaque specimens obtained during carotid endarterectomy were divided into stable group (n=19) and unstable group (n=23) based on histopathological studies (HE staining). Eight aortic arteries and their branches from hepatic transplantation donors were taken as control group. Bcl-2/Bax was detected by immunohistochemistry (IHC) staining (n=42) and in situ hybridization (ISH) (n=25, stable 13/unstable 12).

RESULTSBcl-2 gene expression, which was expressed in smooth muscle cells (SMC), endothelial cells (EC), macrophages (MP) and foam cells, was detected in 20 and 9 cases in unstable plaque while 11 and 4 cases in stable plaque by IHC and ISH, respectively (P < 0.05). Bax, which was expressed in SMC and MP, was detected in 18 and 11 cases in unstable plaque, while 8 and 5 cases in stable plaque by IHC and ISH, respectively (P < 0.05).

CONCLUSIONThe expression rate of Bcl-2/Bax in unstable plaques was higher than in stable plaques. Bcl-2 was one of the elements that maintain plaque stability whereas Bax was one element that facilitates plaque instability. Therefore, Bcl-2/Bax expression in different stage of atherosclerosis may be one of the molecule regulation mechanisms in carotid atherosclerosis.

Apoptosis ; genetics ; Carotid Arteries ; metabolism ; pathology ; Carotid Artery Diseases ; metabolism ; Carotid Stenosis ; metabolism ; pathology ; Endothelium, Vascular ; metabolism ; Humans ; Macrophages ; metabolism ; Muscle, Smooth, Vascular ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; biosynthesis ; genetics ; Up-Regulation ; bcl-2-Associated X Protein

OBJECTIVE: To explore the relationship between hypoxia-inducible foctor-1α (HIF-1α) and neovascularization in early atherosclerosis plaques by establishing rabbit carotid atherosclerosis models, and to observe the value of contrast-enhanced ultrasound in the detection of neovascularization. METHODS: We provided high-fat diet combined with the implantation of silicone rubber ring to establish carotid atherosclerosis in rat models. On the 14th and 28th days, we detected neovascularization in the carotid atherosclerotic plaques by contrast-enhanced ultrasound, obtained the peak intensity (PI) of the contrast agent in the plaques by time-intensity curve (TIC) and analyzed the difference. We also tested the level of HIF-1α, vascular endothelial growth factor (VEGF), cluster of differentiation 31 (CD31), α-actin, and RAM-11 by immunohistochemical method in each group, analyzed their correlation, and the correlation between PI and CD31 expression. RESULTS: On the 14th day, contrast-enhanced ultrasound showed the neovascularization in the carotid atherosclerotic plaques. On the 14th and 28th days, the intensity of contrast-enhanced ultrasound showed significant difference, the mean optical density of HIF-1α, VEGF, CD31, RAM-11, and α-actin within the carotid atherosclerotic plaques also showed statistical difference. The expressions between HIF-1α and VEGF, HIF-1α and CD31, HIF-1α and RAM-11, HIF-1α and α-actin, as well as PI and CD31 showed highly positive correlations. CONCLUSION During the process of atherosclerosis evolution, neovascularization in the atherosclerotic plaques has come into being in the early period, and HIF-1α in early atherosclerosis can promote the formation of neovascularization. Contrast-enhanced ultrasound can detect the dynamic changes of neovascularization within early atherosclerotic plaques.
Animals ; Carotid Artery Diseases ; complications ; metabolism ; pathology ; Disease Models, Animal ; Hypoxia-Inducible Factor 1, alpha Subunit ; metabolism ; Male ; Neovascularization, Pathologic ; etiology ; metabolism ; pathology ; Rabbits

OBJECTIVETo investigate the relationship between insulin resistance and carotid atherosclerosis in patients with potential hyperglycemia.

METHODSA total of 221 patients were recruited among those with potential hyperglycemia. All participants underwent physical examination, medical history interview, and 75 g oral glucose tolerance test. Venous blood was sampled for measurement of insulin and cholesterol levels. The intima-media thickness (IMT) in bilateral common carotid arteries was observed by B-mode ultrasound. Insulin resistance index was calculated by homeostasis model assessment (HOMA-IR). Subjects were stratified in quintiles according to HOMA-IR values. Risk factors and atherosclerotic parameters were analyzed.

RESULTSWith HOMA-IR value increase, incidence of impaired glucose tolerance, diabetes mellitus, hypertension, and coronary artery disease increased, the levels of triglyceride (TG), low density lipoprotein cholesterol (LDL-C), fasting plasma glucose, 2 hour plasma glucose, and fasting insulin increased as well, while the level of high density lipoprotein cholesterol (HDL-C) decreased. Meanwhile, all atherosclerotic parameters increased. Multivariate regression analysis showed that TG, total cholesterol, HDL-C, LDL-C levels, and ln(HOMA-IR) were related to IMT, hence were risk factors for IMT increase.

CONCLUSIONInsulin resistance is implicated in atherogenesis.

Aged ; Blood Glucose ; metabolism ; Carotid Artery Diseases ; blood ; etiology ; Carotid Artery, Common ; pathology ; ultrastructure ; Female ; Glucose Tolerance Test ; Humans ; Hyperglycemia ; blood ; Insulin ; blood ; Insulin Resistance ; Lipids ; blood ; Male ; Middle Aged ; Risk Factors ; Tunica Media ; pathology

OBJECTIVETo evaluate the capability of magnetic resonance imaging (MRI) using different sequences in displaying atherosclerotic carotid plaque composition.

METHODSThirty-five patients received pre- and post-contrast carotid MRI examination on a 3.0T scanner. TOF, T(1)W, T(2)W, PDW and CE-T(1)W were used for identifying the positive and negative cases for the plaque composition (lipid-rich necrotic core, intraplaque hemorrhage and calcification), and their respective sensitivity, specificity and Cohens κ with 95% CI for displaying the components of the plaques were calculated.

RESULTSA total of 74 plaques were found in the 35 patients, and after exclusion of 6 plaques for a thickness below 3 mm, 68 plaques were included for the analysis. Lipid-rich necrotic core were found in 57 plaques, intraplaque hemorrhage in 30 plaques, and alcification in 43 plaques. CE-T(1)W was the optimal sequence for displaying lipid-rich necrotic core with a sensitivity of 100%, specificity of 90.9%, and κ value of 0.944. Both T(1)W and TOF reliably showed the intraplaque hemorrhage, but the former had a greater sensitivity (100%), specificity (92.1%), and κ value (0.911). Of all the 5 sequences, TOF was the best to show calcification with high sensitivity (100%), specificity (92%), and κ value (0.936).

CONCLUSIONCE-T(1)W is the best sequence to show lipid-rich necrotic core with high sensitivity and specificity. T(1)W and TOF show a high level of agreement with the standard to show the intraplaque hemorrhage. TOF is more sensitive and accurate than the other sequences in displaying calcification. The combination of T(1)W, TOF and CE-T(1)W allows accurate evaluation of each component of the plaque.

Adult ; Aged ; Aged, 80 and over ; Carotid Artery Diseases ; diagnosis ; metabolism ; pathology ; Contrast Media ; Female ; Humans ; Magnetic Resonance Imaging ; methods ; Male ; Middle Aged

OBJECTIVETo explore the expression and changes of protooncogene c-myc in early restenosis after carotid endarterectomy (CEA).

METHODSUsing New Zealand Rabbits, carotid atherosclerotic stenosis (CASS) model were created. The expression of c-myc in early restenosis after CEA were detected by quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTSIn this experiment protooncogene c-myc was analysed at pre-operation, 4 hours and 1 d after CEA by qRT-PCR, and the level of mRNA of c-myc was reached maximum at 4 hours, and decreased following significantly, but still higher than pre-operation.

CONCLUSIONSThe activation of protooncogene c-myc may be generator factor of vascular smooth muscle cell proliferation.

Animals ; Carotid Arteries ; metabolism ; pathology ; surgery ; Carotid Artery Diseases ; surgery ; Carotid Stenosis ; etiology ; genetics ; physiopathology ; Disease Models, Animal ; Endarterectomy, Carotid ; adverse effects ; methods ; Gene Expression ; Male ; Postoperative Complications ; etiology ; metabolism ; physiopathology ; Proto-Oncogene Proteins c-myc ; genetics ; RNA, Messenger ; genetics ; metabolism ; Rabbits ; Random Allocation ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVENitric oxide (NO) was speculated to play an important role in the pathophysiology of cerebral ischemia. Minocycline, a tetracycline derivative, reduced inflammation and protected against cerebral ischemia. To study the neuroprotection mechanism of minocycline for vascular dementia, the influences of minocycline on expressions of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) were observed in the brains of Wistar rats.

METHODSThe vascular dementia rat model was established by permanent bilateral common carotid arteries occlusion (BCCAO). Wistar rats were divideded into 3 groups randomly: sham-operation group (S group), vascular dementia model group (M group), and minocycline treatment group (MT group). The behaviour was tested with Morris water maze and open-field task. Expressions of iNOS and eNOS were measured by immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). The optical density value was measured by imaging analysis. Percentage of positive cells with iNOS and eNOS expression was analyzed with optical microscope.

RESULTSMinocycline attenuated cognitive impairment. Inducible NOS was significantly down-regulated in MT group, compared with that in M group (P < 0.01), while eNOS was significantly up-regulated, compared with that in M group (P < 0.01). The expressions of iNOS and eNOS in M and MT groups were higher than those in S group (P < 0.01).

CONCLUSIONMinocycline can down-regulate the expression of iNOS and up-regulate the expression of eNOS in vascular dementia, which restrains apoptosis and oxidative stress to protect neural function.

Animals ; Behavior, Animal ; drug effects ; Carotid Artery Diseases ; complications ; Carotid Artery, Common ; Cognition Disorders ; drug therapy ; etiology ; pathology ; Disease Models, Animal ; Exploratory Behavior ; drug effects ; Female ; Hippocampus ; drug effects ; physiopathology ; Maze Learning ; drug effects ; Minocycline ; therapeutic use ; Nitric Oxide Synthase Type II ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Oxidative Stress ; drug effects ; Rats ; Rats, Wistar ; Reaction Time ; drug effects ; Time Factors

The aim of this study was to identify the main factor affecting compliance and intima-media thickness of the elastic common carotid artery in continuous ambulatory peritoneal dialysis patients. Increased intima-media thickness and decreased arterial compliance are associated with elevated risk of cardiovascular disease. This study included 20 patients and 20 age- and sex- matched healthy control subjects. The compliance and intima-media thickness of the right common carotid artery within 1 cm to the bifurcation were measured three times using high-resolution B-mode echocardiography. Blood samples were obtained to measure levels of hemoglobin, phosphorus, total calcium, total CO2, serum albumin, C-reactive protein, serum total cholesterol, LDL- and HDL-cholesterol and triglycerides. We found that the compliance of common carotid artery was lower in the patient group than in the control group. In the patient group, the compliance of common carotid artery was positively correlated with serum albumin concentration, and intima-media thickness of common carotid artery was negatively correlated with serum albumin levels. Stepwise regression analysis showed that serum albumin concentration was independently related to the compliance of common carotid artery, suggesting hypoalbuminemia can independently give deleterious effects on the arterial wall in continuous ambulatory peritoneal dialysis patients.
Aged ; Albumins/metabolism ; Arteries/pathology ; C-Reactive Protein ; Carbon Dioxide ; Cardiovascular Diseases ; Carotid Arteries/*pathology ; Carotid Artery, Common/pathology ; Dose-Response Relationship, Drug ; Echocardiography ; Female ; Hemoglobins/metabolism ; Humans ; Hypoalbuminemia/*pathology ; Lipoproteins, HDL Cholesterol/blood ; Lipoproteins, LDL Cholesterol/blood ; Male ; Middle Aged ; Peritoneal Dialysis ; Peritoneal Dialysis, Continuous Ambulatory/methods ; Phosphorus/blood ; Regression Analysis ; Research Support, Non-U.S. Gov't ; Serum Albumin/metabolism ; Tunica Intima/pathology ; Tunica Media/pathology

OBJECTIVETo investigate the effects of carvedilol on stabilizing atherosclerosis plaque.

METHODSForty five male Japanese white rabbits were divided randomly into 5 groups with 9 for each. One group was fed up with normal diet as blank control. In other four groups, the common carotid artery of rabbits fed up with high cholesterol diet were injured by balloon. Three groups of them were transfected by wild-type p53 gene 8 weeks later, and then two groups of them were treated with carvedilol (3 mgxkg(-1)xd(-1)) and metoprolol (6 mgxkg(-1)xd(-1)) respectively, high cholesterol diet should be continued for other 4 weeks. Serum lipid, hypersensitive C-reaction protein (hsCRP), oxidized low density lipoprotein (oxLDL), superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-PX) were measured in 0, 8, 12 weeks after experiment. The apoptosis rate of smooth muscle cell (SMC) in endomembrane and the local expression of p53, bcl-2, bax, alpha-actin were examined after experiment, and the carotid arteries were examined by light microscopy and transmission electron microscopy.

RESULTSThe typical carotid atherosclerotic plaques were observed in balloon-injured groups. The local expression rates of p53 in groups transfected by wild type p53 gene were higher obviously than them in other two groups (P < 0.01). Compared with the rabbits received simple transfection, the thickness of the fibrous cap in rabbits received carvedilol and metoprolol were all increased, but the change could be observed significantly in carvedilol group (P < 0.05). Compared with metoprolol, carvedilol could reduce the level of serum hsCRP, oxLDL, MDA, and increase the concentration of SOD and GSH-PX significantly (P < 0.05 or 0.01), but two medicines had no obvious influence to serum lipid. The apoptosis rate of SMC in endomembrane, the local expression of bax gene and bax/bcl-2 ratio were decreased, the positive expression rates of alpha-actin and bcl-2 were enhanced in carvedilol group (P < 0.01).

CONCLUSIONSBoth carvedilol and metoprolol can improve the stability of the plaque, but carvedilol is superior. Its mechanisms may lie in that carvedilol still has function of anti-inflammation, anti-oxidation, decreasing the apoptosis rate of SMC in addition to its function of blocking beta-receptor.

Animal Feed ; Animals ; Apoptosis ; drug effects ; Carbazoles ; pharmacology ; Carotid Artery Diseases ; genetics ; pathology ; Genes, p53 ; Humans ; Male ; Metoprolol ; pharmacology ; Oxidative Stress ; drug effects ; Propanolamines ; pharmacology ; Rabbits ; Transfection ; Tumor Suppressor Protein p53 ; genetics ; metabolism

Advanced glycation endproducts (AGEs) have been reported to play a role in neointimal formation and increase the rate of in-stent restenosis (ISR) in the diabetic coronary artery disease patients treated with stents, but the potential pathogenic mechanisms of AGEs in vascular smooth muscle cell proliferation remain unclear. We sought to determine the AGEs related pathobiological mechanism of diabetic vasculopathy. Rat aortic smooth muscle cell (RAoSMC) culture was done with different concentrations of AGEs and proliferation was assessed. Immunohistochemistry for receptor of AGEs (RAGE) was performed with human carotid atheroma. Western blotting was performed to assess the activation of MAP kinase system in the cultured RAoSMC. AGEs increased RAoSMC proliferation and were associated with increased phosphorylation of ERK and p38 kinase by time and dose dependent manner. The MAP kinase activity was decreased by RNA interference for RAGE. AGEs stimulation increased reactive oxygen species (ROS) generation in cultured RAoSMC. From this study it is concluded that AGEs played a key role in RAoSMC proliferation via MAP kinase dependent pathways. Activation of vascular smooth muscle cell (VSMC) proliferation by MAP kinase system and increased formation of ROS may be the possible mechanisms of AGEs induced diabetic vasculopathy.
Animals ; Carotid Artery Diseases/metabolism/pathology ; Cell Proliferation/drug effects ; Cells, Cultured ; Diabetic Angiopathies/*etiology/metabolism/pathology ; Extracellular Signal-Regulated MAP Kinases/metabolism ; Glycosylation End Products, Advanced/adverse ; Humans ; MAP Kinase Signaling System/drug effects/*physiology ; Phosphorylation/drug effects ; RNA, Small Interfering/pharmacology ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species/metabolism ; Receptors, Immunologic/antagonists & inhibitors/metabolism

OBJECTIVETo investigate the relationship between carotid artery intima media thickness (IMT) and apolipoprotein (Apo) E gene polymorphisms in type 2 diabetes mellitus (DM2).

METHODSTwo hundred and fifty-five DM2 patients without angiopathy and 107 healthy individuals were selected. PCR/allele-specific oligonucleotide probe was used to determine their apoE genotypes.

RESULTSThe prevalence distribution of apoE genotypes and alleles in DM2 patients and that in controls were similar. The TC, LDL-C and Lp(a) concentrations in e4/4, e4/3 subgroups were significantly higher than those in e3/2, e2/2 subgroups (P<0.05). The average value of IMT in e4/4 e4/3 carriers (0.89 mm) was significantly greater than that in e3/2 e2/2 carriers (0.62 mm) (P<0.05). After adjustment for TC, LDL-C, TG, Lp(a), FBG, HbA1c, age, BMI, and smoking, ANCOVA showed that the average value of carotid IMT was significantly greater in subjects with e4/4 e4/3, compared with that in subjects with e3/2 e2/2(P=0.033).

CONCLUSIONApo e4 allele increases the risk for carotid artery atherosclerosis in the early stage of diabetic population.

Adult ; Age Factors ; Aged ; Aged, 80 and over ; Alleles ; Analysis of Variance ; Apolipoprotein E4 ; Apolipoproteins E ; genetics ; Arteriosclerosis ; pathology ; Body Mass Index ; Carotid Artery Diseases ; pathology ; Cholesterol ; blood ; Cholesterol, LDL ; blood ; Diabetes Mellitus, Type 2 ; blood ; genetics ; pathology ; Female ; Gene Frequency ; Genotype ; Glycated Hemoglobin A ; metabolism ; Humans ; Lipoprotein(a) ; blood ; Male ; Middle Aged ; Smoking ; Triglycerides ; blood ; Tunica Intima ; pathology ; Tunica Media ; pathology