OBJECTIVETo study the expression of cell cycle related factor sonic hedgehog (SHH) in autogenous vein graft and its relation with neointima formation.

METHODSAutogenous vein graft model were established in 24 male Wistar rats of 8 weeks old and 140 g weight, by transplanting the left jugular vein to intra renal abdominal aorta with microsurgical technique. Graft veins were harvested at 14 d and 28 d after transplantation. The immunohistochemistry and Western blot were used to detect the SHH and PCNA expression in the vein graft. At the same time SHH mRNA was measured by quantitative real-time PCR. The opposite normal veins served as control.

RESULTSHistological staining showed that the percent of SHH+ cells was only (2.0 +/- 0.5)% in the normal vein, but was much more in the vein graft after surgery, as (39.4 +/- 0.4)% and (63.0 +/- 0.3)% respectively (P < 0.01). The expression of SHH and PCNA were both elevated in the vein graft. There was a positive correlation between them which indicated by Western blot (r = 0.808, P < 0.01). The SHH mRNA content also increased in vein graft to 9.5 and 23.8 folds of that in control.

CONCLUSIONSHH is upregulated in autogenous vein grafts and may correlated with the proliferation of vascular smooth muscle cells.

Animals ; Hedgehog Proteins ; metabolism ; Male ; Neointima ; metabolism ; Rats ; Rats, Wistar ; Transplantation, Autologous ; Tunica Intima ; metabolism ; Veins ; metabolism ; pathology ; transplantation

Aged ; Carotid Artery, Common ; pathology ; Diabetes Mellitus, Type 2 ; metabolism ; pathology ; Female ; Glucose Intolerance ; metabolism ; pathology ; Glucose Tolerance Test ; Humans ; Insulin Resistance ; Male ; Tunica Intima ; pathology

AIM AND METHODSTo determine the relationship between the nuclear envelope nucleoside triphosphatase (EC 3. 6. 1. 15, NTPase) activity and the phenotypic modulation of vascular smooth muscle cell (VSMC), the NTPase activity was detected during restenosis after de-endothelialization in vascular wall. The activities of three enzymes involved in carbohydrate and nucleic acid metabolism were also investigated by spectrophotometry.

RESULTSThe activity of NTPase increased continuously and associated with the process of intimal thickening. Western blotting showed that expression of SMalpha-actin, as the marker of contractile phenotype of VSMC, decreased continuously. Osteopontin (OPN), the marker of synthetic phenotype of VSMC, was up-regulated during the process. These suggested that intimal injury induced phenotypic modulation of VSMC. The activities of 5'-nucleotidase, adenosine deaminase and succinate dehydrogenase increased and reached their peaks on 7 days after de-endothelialization. The changes of three enzymes were associated with proliferation in VSMC.

CONCLUSIONThe efflux of mRNA and the changes of enzyme activity involved in carbohydrate or nucleic acid metabolism may be the biochemical basis in the development and progression of restenosis.

Animals ; Constriction, Pathologic ; Endothelium, Vascular ; pathology ; Female ; Hyperplasia ; enzymology ; pathology ; Male ; Muscle, Smooth, Vascular ; pathology ; Nucleoside-Triphosphatase ; metabolism ; Rats ; Rats, Sprague-Dawley ; Tunica Intima ; enzymology ; pathology

Arterial restenosis frequently develops after open or endovascular surgery due to intimal hyperplasia. Since tissue transglutaminase (TG2) is known to involve in fibrosis, wound healing, and extracellular matrix remodeling, we examined the role of TG2 in the process of intimal hyperplasia using TG2-null mice. The neointimal formation was compared between TG2-null and wild-type (C57BL/6) mice by two different injury models; carotid ligation and carotid loop injury. In ligation model, there was no difference in intimal thickness between two groups. In loop injury model, intimal hyperplasia developed in both groups and the intimal/medial area ratio was significantly reduced in TG2-null mice (P = 0.007). TG2 was intensely stained in neointimal cells in 2 weeks. In situ activity of TG2 in the injured arteries steadily increased until 4 weeks compared to uninjured arteries. Taken together, intimal hyperplasia was significantly reduced in TG2-null mice, indicating that TG2 has an important role in the development of intimal hyperplasia. This suggests that TG2 may be a novel target to prevent the arterial restenosis after vascular surgery.
Animals ; Carotid Arteries/pathology/*surgery ; Disease Models, Animal ; GTP-Binding Proteins/deficiency/genetics/*metabolism ; Hyperplasia ; Mice ; Mice, Inbred C57BL ; Transglutaminases/deficiency/genetics/*metabolism ; Tunica Intima/*pathology

BACKGROUNDAtherosclerosis is a chronic inflammatory disease. Accumulated evidences suggest a deep involvement of oxidative damage in the development of atherosclerosis, but little is discussed over the relationship between plasma glutathione redox status as the most important intrinsic antioxidant defensive mechanism and the atherosclerosis.

METHODSA total of 132 patients suspected with atherosclerosis were assigned to three groups by high frequency ultrasonic examination of the carotid artery. With the thickness of intima of the carotid artery as an index of degree of atherosclerosis progression, 56 were included in plaque-forming group (A), 42 in carotid artery intima-thickening group (B), and 34 in normal carotid artery intima-thickness group (C). All patients were subjected to the measurement of plasma glutathione (GSH) (reduced form GSH and oxidized form GSSG), nicotinamide adenine dinucleotide phosphate (NADP) (reduced form NADPH and oxidized form NADP(+)), oxidized low density lipoprotein (oxLDL), and malondialdehyde (MDA). The GSH/GSSG and NADPH/NADP(+) redox potentials were calculated according to the Nernst equation, and their correlation with intima thickness and oxLDL was analyzed.

RESULTSWith the thickening of artery intima (from group C to A), GSH concentration and the ratio of GSH/GSSG gradually reduced, and GSSG and GSH/GSSG redox potential gradually increased (more positive) (P < 0.05). The NADPH and NADPH/NADP(+) redox status also showed similar but milder changes. The products of oxidative stress oxLDL and MDA increased significantly along with the thickening of artery intima (P < 0.05). The analysis of the relationship between GSH/GSSG redox potential, intima thickness, and oxLDL showed positive correlations (P < 0.05). The plasma GSH/GSSG redox status was positively correlated with the intima thickness of the carotid artery and the oxidized injury of LDL. The redox status shifted to oxidizing direction along with the intima thickening and plaque-forming.

CONCLUSIONElevated peroxidative glutathione redox status was deeply implicated in atherosclerosis progressing, and it may be a sensitive and reliable index for monitoring oxidative status in atherosclerosis.

Adult ; Aged ; Atherosclerosis ; metabolism ; pathology ; Carotid Arteries ; pathology ; Female ; Glutathione ; blood ; Glutathione Disulfide ; blood ; Humans ; Lipid Peroxidation ; Male ; Middle Aged ; NADP ; blood ; Oxidative Stress ; Tunica Intima ; pathology ; Tunica Media ; pathology

The aim of this study was to investigate the relationship between obesity, insulin resistance and atherosclerosis in type 2 diabetes mellitus (T2DM) patients. Total 530 patients with T2DM were included. To evaluate the severity of atherosclerosis, we measured the coronary artery calcification (CAC) score, intima-media thickness (IMT) of the common carotid artery, and the ankle-brachial pressure index (ABPI). Subjects were classified according to body mass index (BMI), a marker of general obesity, and waist-to-hip ratio (WHR), a marker of regional obesity. The insulin sensitivity index (ISI) was measured by the short insulin tolerance test. All subjects were classified into four groups, according to BMI: the under-weight group, the normal-weight (NW) group, the over-weight (OW) group, and the obese (OB) group. WHR and systolic blood pressure, triglycerides (TG), HDL-cholesterol (HDLC), free fatty acids (FFA), fibrinogen, and fasting c-peptide levels were significantly different between BMI groups. TG, HDL-C, FFA, fibrinogen and ISI were significantly different between patients with and without abdominal obesity. In the OW group as well as in the NW group, carotid IMT, ABPI and CAC score were significantly different between patients with and without abdominal obesity. This study indicates that abdominal obesity was associated with atherosclerosis in T2DM patients.
Aged ; Atherosclerosis/complications ; Blood Pressure ; Coronary Vessels/pathology ; Diabetes Complications ; Diabetes Mellitus, Type 2/*genetics ; Female ; Humans ; Insulin Resistance ; Korea ; Male ; Middle Aged ; Obesity/*complications/*genetics ; Triglycerides/metabolism ; Tunica Intima/pathology ; Tunica Media/pathology

BACKGROUNDPost-stenting restenosis is a significant clinical problem, involving vascular smooth muscle cells (VSMCs) proliferation and apoptosis. It is reported that c-myc antisense oligodeoxynucleotides (ASODNs) local delivered by catheter can inhibit VSMCs proliferation. This study was designed to assess tissue distribution of c-myc ASODN local delivered using gelatin-coated platinum-iridium (Pt-Ir) stents, and its effect on apoptosis of VSMCs.

METHODSGelatin-coated Pt-Ir stents that had absorbed caroboxyfluorescein-5-succimidyl ester (FAM) labeled c-myc ASODNs (550 microg per stent) were implanted into the right carotid arteries of 6 rabbits. Tissue samples were obtained at 45 minutes, 2 hours, and 6 hours. Tissue distribution of c-myc ASODNs was assessed by fluorescence microscopy. In addition, 32 rabbits were randomly divided into two groups. Rabbits in the control group (n = 16) were implanted with gelatin-coated Pt-Ir stents, and those in the treatment group (n = 16) were implanted with gelatin-coated stents that had absorbed c-myc ASODNs. 7, 14, 30, or 90 days (n = 4, respectively, for each group) after the stenting procedure, the stented segments were harvested, and histopathological examinations were performed to calculate neointimal area and mean neointimal thickness. The expression of c-myc was assessed using in situ hybridization (ISH) and immunohistochemical methods. Apoptotic VSMCs were detected using terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) and transmission electron microscope (TEM).

RESULTSAccording to fluorescence microscopic results, FAM-labeled c-myc ASODNs were concentrated in the target vessel media at the 45 minutes time point, and then dispersed to the adventitia. Morphometric analysis showed that neointimal area and mean neointimal thickness increased continuously up to 90 days after stent implantation, but that total neointimal area and mean neointimal thickness were less in the treatment group than in the control group at all time points (P < 0.0001). At day 7 and day 14 after stenting, there were no detectable apoptotic cells in either group. However, apoptotic cells were present in the neointima 30 and 90 days after stenting, and the number of apoptotic cells was less at 30 days than at 90 days. Meanwhile, c-myc ASODNs appeared to induce apoptosis in more cells in the treatment group than that in the control group. Typical apoptotic VSMCs were observable under TEM. The expression of c-myc was positive in the control group and negative or weakly positive in the c-myc ASODN treatment group, according to both ISH and immunohistochemical examination.

CONCLUSIONGelatin-coated Pt-Ir stent mediated local delivery of c-myc ASODNs is feasible. The localization of c-myc ASODN is primarily in the target vessel walls. c-myc ASODNs can inhibit VSMCs proliferation and induce its apoptosis after local delivery in vivo.

Animals ; Apoptosis ; drug effects ; Carotid Arteries ; Female ; Gelatin ; Genes, myb ; genetics ; In Situ Hybridization ; Iridium ; Male ; Microscopy, Fluorescence ; Myocytes, Smooth Muscle ; pathology ; Oligodeoxyribonucleotides, Antisense ; administration & dosage ; metabolism ; pharmacology ; Platinum ; Rabbits ; Random Allocation ; Stents ; Tissue Distribution ; Tunica Intima ; metabolism ; Tunica Media ; metabolism

AIMOsteopontin 13-peptide(Gly158-Lys170), containing multi-function domains was used to inhibit the VSMC adhesion, migration. The mechanism of 13-peptide inhibiting neointima formation was investigated.

METHODSThe effect of 13-peptide on VSMC adhesion was tested by adhesion assay. The restenosis model was prepared balloon injury after administration of 13-peptide for 1 h, and then the 13-peptide was given by an intravenous drip for 7 days. The expression changes of OPN, FAK, ILK in vessel wall were detected by immunohistochemistry and Western blot.

RESULTSThe 13-peptide dose-dependently reduced adhesion of VSMC in OPN matrix, and the infiltration of macrophage in vessel wall also was reduced in the treatment group after balloon injury. The expression of OPN, FAK, ILK was down-regulated following with the inhibition of neointima thickening.

CONCLUSIONThe OPN 13-peptide can inhibit inflammation and neointima formation by blocking the binding of OPN to it's receptors.

Animals ; Cell Adhesion ; drug effects ; Cells, Cultured ; Disease Models, Animal ; Male ; Muscle, Smooth, Vascular ; cytology ; drug effects ; metabolism ; Osteopontin ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Tunica Intima ; pathology

BACKGROUNDThe autologous saphenous vein is the most common conduit for coronary artery bypass grafting, but the vein graft disease will occur. This study used Matrigel basement membrane matrix with many different growth factors to promote vasa vasorum neovascularization and extenuate the hypoxia to improve remodeling.

METHODSThis study observed the hypoxia and thickness of the vein grafts at different times. Normal veins and vein grafts with 15 min of ischemia one day postoperatively were harvested in the neck of rabbits. Paired vein grafts with 15 min ischemia bilaterally (control vs. Matrigel basement membrane matrix) were performed and harvested at 2, 6, and 12 weeks postoperatively. The rabbits were randomly divided into four postoperative groups (six rabbits in each group): Group 1, one day postoperatively; Group 2, 2 weeks postoperatively; Group 3, 6 weeks postoperatively; and Group 4, 12 weeks postoperatively. The dimensions of vessel wall were captured, and the mean thicknesses of intima, media, and adventitia were measured. The hypoxia-inducible factor (HIF)-1α and HIF-2α labeling indices of intima, media, and adventitia were also measured.

RESULTSIn Group 1, the labeling index of HIF-1α was high in the normal vein and decreased significantly in the vein graft one day postoperatively (intima: 80 ± 3% vs. 12 ± 1%, P = 0.01; media: 67 ± 5% vs. 11 ± 1%, P = 0.01; adventitia: 40 ± 10% vs. 7 ± 2%, P = 0.03). The labeling index of HIF-2α had similar trend as HIF-1α (intima: 80 ± 10% vs. 10 ± 5%, P = 0.02; media: 60 ± 14% vs. 12 ± 2%, P = 0.01; adventitia: 45 ± 20% vs. 10 ± 4%, P = 0.03). Compared with the control vein grafts, vein grafts with Matrigel basement membrane matrix had lower labeling indices of HIF-1α and HIF-2α in media and adventitia at Group 2 (HIF-1α: 34 ± 5% vs. 20 ± 4%, P = 0.04 for media; 23 ± 3% vs. 11 ± 2%, P = 0.03 for adventitia; HIF-2α: 37 ± 6% vs. 21 ± 4%, P = 0.03 for media; 24 ± 4% vs. 13 ± 2%, P = 0.04 for adventitia) and Group 3 (HIF-1α: 33 ± 4% vs. 7 ± 2%, P = 0.04 for media; 13 ± 3% vs. 3 ± 1%, P = 0.02 for adventitia; HIF-2α: 27 ± 4% vs. 12 ± 3%, P = 0.02 for media; 19 ± 2% vs. 6 ± 1%, P = 0.02 for adventitia). There were no differences in mean thickness of intima, media, and adventitia between bilateral vein grafts at 2, 6, and 12 weeks postoperatively.

CONCLUSIONSThis study indicated that promoting vasa vasorum neovascularization of vein grafts extenuated hypoxia, but did not influence the intimal hyperplasia of the wall.

Animals ; Basic Helix-Loop-Helix Transcription Factors ; metabolism ; Hyperplasia ; pathology ; Hypoxia-Inducible Factor 1 ; metabolism ; Hypoxia-Inducible Factor 1, alpha Subunit ; metabolism ; Neovascularization, Pathologic ; pathology ; Postoperative Period ; Rabbits ; Saphenous Vein ; pathology ; Tunica Intima ; pathology ; Vasa Vasorum ; pathology

OBJECTIVETo assess the effect of valsartan eluting-stents on restenosis and collagen deposition in neointima hyperplasia in rabbits.

METHODSValsartan eluting-stents and the carrier eluting-stents were made with patented multi-layers coating techniques. Bare stents (n = 8), carrier eluting-stents (n = 8) and valsartan eluting-stents (n = 10) were implanted into rabbit abdominal aortas, respectively. Quantitive angiography (QA) was performed before, immediately post and 3 months after stents implantations to determine the diameter of aortas. Rabbits were killed 3 months post stents implantation and the cross sections of the stented vessels were analyzed for neointimal formation: luminal area (LA), neointimal area (NIA), inner elastic lumina area (IELA), the maximal inner-membrane thickness (MIT) and percent stenosis. MASSON and picrosirius red staining were performed to observe the collagen deposition in neointima analyzed.

RESULTSThe mean aortic diameters measured by QA at different time points were similar between the groups. LA was significantly larger (5 016 269 microm(2) +/- 207,934 microm(2) vs. 4,345,548 microm(2) +/- 125,822 microm(2) and 4,302,061 microm(2) +/- 167,952 microm(2), P < 0.01 vs. valsartan stents) while NIA (441,577 microm(2) +/- 74,099 microm(2) vs. 1,119,635 microm(2) +/- 163,503 microm(2) and 1,135,636 microm(2) +/- 136,555 microm(2)) and MIT (116 microm +/- 12 microm vs. 240 microm +/- 30 microm and 192 microm +/- 21 microm) as well as percent stenosis (8% +/- 2% vs. 20% +/- 2% and 21% +/- 2%) were significantly reduced in valsartan eluting-stents group compared to bare and carrier stents groups. MASSON and picrosirius red staining revealed rich type III collagen deposition in neointima and spare type I collagen patched around stents struts in bare and carrier stents groups and collagen deposition was rarely seen in neointima and stents struts in valsartan eluting-stents group.

CONCLUSIONValsartan eluting-stents inhibited neointimal hyperplasia by decreasing collagen deposition.

Animals ; Collagen ; metabolism ; Coronary Restenosis ; metabolism ; pathology ; therapy ; Coronary Vessels ; pathology ; Drug-Eluting Stents ; Female ; Graft Occlusion, Vascular ; metabolism ; pathology ; Hyperplasia ; Male ; Rabbits ; Tetrazoles ; therapeutic use ; Tunica Intima ; pathology ; Valine ; analogs & derivatives ; therapeutic use ; Valsartan