Efficacy and safety of Danhong injection on endothelial function and inflammatory factors after the percutaneous coronary intervention for coronary heart disease: A protocol of systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: To systematically review the effects of Danhong injection on endothelial function and inflammatory factors after the percutaneous coronary intervention (PCI) for coronary heart disease (CHD) and to provide a basis for further research. METHODS: Through computer retrieval, including PubMed, Embase, the Cochrane Library, CNKI, Wan Fang Data, VIP, SinoMed were retrieved on a computer. Randomized controlled trials (RCTs) on the effects of Danhong injection on endothelial function and inflammatory factors after PCI for CHD were collected in strict accordance with the pre-established inclusion and exclusion criteria. Chinese and English literatures in published from the establishment of each database to December 1, 2019, were retrieved by combining subject headings and free terms. Literatures were screened out by 2 researchers independently, and the risk of bias was assessed by 2 independent researchers by using the assessment tool for risk of bias as described Cochrane systematic reviewer's manual 5.1.0. Statistical analysis was performed by using Stata 14.0 software. RESULTS: By collecting the existing evidence, this study would determine the effects of Danhong injection on endothelial function and inflammatory factors after PCI for CHD by meta-analysis. CONCLUSION: Through this study, we will draw a definite conclusion on whether Danhong injection has significant effects on endothelial function and inflammatory factors after PCI for CHD. This conclusion will provide practical and scientific guidance for the use of Danhong injection after PCI for CHD. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42020165568.

Danhong injection mobilizes endothelial progenitor cells to repair vascular endothelium injury via upregulating the expression of Akt, eNOS and MMP-9.

BACKGROUD: Endothelial progenitor cells (EPCs) have been characterized as one of the key effectors of endothelial healing. The effect of Danhong injection (DHI), the most widely prescribed Chinese medicine for coronary heart disease (CHD), on EPCs mobilization remains unclear. PURPOSE: We aimed to assess the effect of DHI on EPCs mobilization to repair percutaneous coronary intervention (PCI) induced vascular injury, and to investigate the characteristics and potential mechanism of DHI on EPCs mobilization. METHOD: Forty-two patients with CHD underwent PCI and received stent implantation were enrolled in a Phase II clinical trials. All patients received routine western medical treatment after PCI, patients of DHI group received DHI in addition. The levels of CECs, cytokines (vWF, IL-6, CRP) and EPCs were analyzed at baseline, post-PCI and after treatment. To investigate the characteristics of DHI on EPCs mobilization, 12 healthy volunteers received intravenous infusion of DHI once and the other 12 received for 7 days. EPCs enumeration were done at a series of time points. At last we tested the effect of DHI and three chemical constituents of DHI (danshensu; lithospermic acid, LA; salvianolic acid D, SaD) on EPCs level and expression of Akt, eNOS and MMP-9 in bone marrow cells of myocardial infarction (MI) mice. RESULTS: In the DHI group the angina symptoms were improved, the levels of cytokines and CECs were reduced; while EPCs population was increased after treatment. In the phase I clinical trials, EPCs counts reached a plateau phase in 9 h and maintained for more than 10 h after a single dose. After continuous administration, EPCs levels plateaued on the 3rd or 4th day, and maintain till 1 day after the withdrawal, then its levels gradually declined. DHI treatment induced a timely dependent mobilization of EPCs. DHI promoted EPCs mobilization via upregulating the expression of Akt, eNOS and MMP-9 in BM. LA and SaD have played a valuable role in EPCs mobilization. CONCLUSION: These initial results demonstrated that DHI is effective in alleviating endothelial injury and promoting endothelial repair through enhancing EPCs mobilization and revealed the effect feature and possible mechanisms of DHI in mobilizing EPCs.

Damaging Effects of Total Parenteral Nutrition Formula on Vascular Endothelium.

OBJECTIVES: Sepsis in one of the most serious complications that can occur during total parenteral nutrition (TPN) procedures. In this experimental study, we investigated the effects of TPN, with or without lipid emulsion, on vascular endothelial damage. METHODS: In total, 50 rabbits were used, divided into 5 groups of 10 each. TPN with lipids (group 1), TPN without lipids (group 2), and 0.09% saline (group 3) were given for 10 days via a central venous catheter. Group 4 received no treatment other than placement of a central venous catheter for 10 days. Group 5 was a control group. At the end of day 10, rabbits were sacrificed and tissue samples of liver, kidney, and inferior vena cava were prepared and examined by immunohistochemical methods for vascular cellular adhesion molecule (VCAM)-1 expression. RESULTS: In tissue sections of liver, kidney, and inferior vena cava, VCAM-1 activity was increased prominently in TPN with and without lipids compared with the control group. VCAM-1 activity in the TPN with lipids group was decreased versus the TPN without lipids group (P > 0.05). CONCLUSIONS: The TPN procedure results in vascular endothelial cell damage not only in the vein where the solution is introduced but also in other parts of the vascular system. Even if it is not statistically significant, lipids in the TPN formula may decrease this endothelial cell damage, as shown by immunohistochemistry.

CD144+ endothelial microparticles as a marker of endothelial injury in neonatal ABO blood group incompatibility.

BACKGROUND: ABO antigens are expressed on the surfaces of red blood cells and the vascular endothelium. We studied circulating endothelial microparticles (EMP) in ABO haemolytic disease of the newborn (ABO HDN) as a marker of endothelial activation to test a hypothesis of possible endothelial injury in neonates with ABO HDN, and its relation with the occurrence and severity of haemolysis. MATERIAL AND METHODS: Forty-five neonates with ABO HDN were compared with 20 neonates with Rhesus incompatibility (Rh HDN; haemolytic controls) and 20 healthy neonates with matched mother and infant blood groups (healthy controls). Laboratory investigations were done for markers of haemolysis and von Willebrand factor antigen (vWF Ag). EMP (CD144(+)) levels were measured before and after therapy (exchange transfusion and/or phototherapy). RESULTS: vWF Ag and pre-therapy EMP levels were higher in infants with ABO HDN or Rh HDN than in healthy controls, and were significantly higher in babies with ABO HDN than in those with Rh HDN (p<0.05). In ABO HDN, pre-therapy EMP levels were higher in patients with severe hyperbilirubinaemia than in those with mild and moderate disease or those with Rh HDN (p<0.001). Post-therapy EMP levels were lower than pre-therapy levels in both the ABO HDN and Rh HDN groups; however, the decline in EMP levels was particularly evident after exchange transfusion in ABO neonates with severe hyperbilirubinaemia (p<0.001). Multiple regression analysis revealed that the concentrations of haemoglobin, lactate dehydrogenase and indirect bilirubin were independently correlated with pre-therapy EMP levels in ABO HDN. DISCUSSION: Elevated EMP levels in ABO HDN may reflect an IgG-mediated endothelial injury parallel to the IgG-mediated erythrocyte destruction and could serve as a surrogate marker of vascular dysfunction and disease severity in neonates with this condition.

Early initiation of low-dose atorvastatin treatment after an acute ST-elevated myocardial infarction, decreases inflammatory process and prevents endothelial injury and activation.

BACKGROUND: High-dose statin treatment improves clinical outcome of ST-elevated myocardial infarction (STEMI). However, the effect of low-dose atorvastatin treatment on inflammatory and pro-thrombotic molecules during the post-STEMI period is unclear. We investigated the effect of low-dose atorvastatin treatment on the kinetics of cytokine IL-6, vascular cell adhesion molecule (sVCAM-1) and endothelium-derived markers of thrombosis/fibrinolysis such as von Willebrand factor (vWF), plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA), post STEMI. METHODS: Twenty-four normocholesterolemic patients with STEMI were randomised to receive atorvastatin 10mg/day or no statin treatment for 6 weeks after the event. Blood samples were obtained by their admission to the hospital as well as at weeks 1 and 6. Circulating levels of IL-6, sVCAM-1, vWF, PAI-1 and tPA were determined by ELISA. RESULTS: Atorvastatin induced a decrease of IL-6 at 1 week, an effect which reached significance compared to baseline at 6 weeks post STEMI (p<0.05 vs baseline). Serum sVCAM-1 was increased in controls both at 1 and 6 weeks post-STEMI (p<0.05 vs baseline), an effect prevented by atorvastatin. Plasma vWF was increased 1 week post-STEMI in controls (p<0.05 vs baseline) and returned to baseline at 6 weeks, an effect prevented by atorvastatin. Plasma PAI-1, tPA and the PAI-1/tPA ratio remained unchanged in both groups. CONCLUSION: Early initiation of low-dose atorvastatin treatment decreases the expression of IL-6 and sVCAM-1 and the release of vWF in patients with STEMI. Therefore, low-dose atorvastatin, modulates inflammatory response and decreases endothelial injury and activation in patients with recent STEMI.

Liquen «aureus» / Lichen aureus

El liquen aureus es una entidad rara, englobada dentro de un grupo de enfermedades denominadas dermatosis purpúricas pigmentarias. Todas ellas son, básicamente, capilaritis de origen desconocido, caracterizadas histológicamente por un infiltrado perivascular de linfocitos T, extravasación de eritrocitos y depósitos de hemosiderina. Aparece predominantemente en niños y adultos jóvenes de cualquier raza, con más frecuencia en hombres que en mujeres. La biopsia cutánea confirma el diagnóstico. Las lesiones cutáneas suelen ser asintomáticas, aunque en algunos casos puede aparecer un prurito intenso. Tienden a la cronicidad, y se ha descrito, sobre todo en niños, la resolución espontánea al cabo de varios años. La respuesta al tratamiento suele ser bastante limitada. Los corticoides tópicos potentes rara vez son eficaces; en algunos casos, se ha intentado el tratamiento con fototerapia (PUVA), pimecrolimus o pentoxifilina, con resultados variables

Lichen aureus is one of the subtypes of a rare group of diseases referred to as pigmented purpuric dermatoses. They are essentially a capillaritis of unknown origin. Histologically, they are characterized by a perivascular T-cell lymphocytic infiltrate centered on the superficial small blood vessels of the skin. Extravasation of red blood cells with marked hemosiderin deposition in macrophages is also found. It occurs predominantly in children and young adults of any race, more frequently in men than in women. A skin biopsy helps to confirm the diagnosis. The eruption is usually asymptomatic, but pruritus may be a prominent feature in some cases. The lesions usually persist unchanged for many years. Complete resolution rarely occurs, being more frequent in children than in adults. The response to treatment is usually quite limited. Potent topical steroids are rarely effective. Ultraviolet A phototherapy (PUVA), pimecrolimus or pentoxifylline have been reported to be beneficial in some cases

[Effect of Tongxinluo on 7 gene expression profile associated with vascular endothelium injure of rats with deficiency of vital energy or qi stagnation].

OBJECTIVE: To investigate 7 gene expression profile associated with inflammation and oxidative stress in vascular endothelium injure of rats with deficiency of vital energy or qi stagnation, and the effect of Tongxinluo on gene expression profile. METHOD: The model of vascular endothelium injury of rats with deficiency of vital energy or qi stagnation were established by using high L-methionine, with load-carrying swimming or being fastened, respectively. RT-PCR and SAGE database which is available in NCBI, were used to analyze the changes of 7 gene expression related with inflammation and oxidative stress in endothelium injure and the effect of Tongxinluo on the gene expression profile. RESULT: Compared with control group, the gene expression of inflammation related COX-1, COX-2, oxidative stress related iNOS, SOD and blood vessel vasomotion related eNOS, ECE, increased in deficiency of vital energy group (P < 0.05 or P < 0.01), and the gene expression decreased with Tongxinluo treatment (P < 0.05 or P < 0.01). The gene expression of COX-1, COX-2, iNOS and eNOS, ECE, increased (P < 0.01), but the gene expression of PCS and SOD decreased (P < 0.01), in qi stagnation group, and the disorder of gene expression improved with treatment of Tongxinluo (P < 0.01). CONCLUSION: The 7 gene expression related to vascular endothelium injure were not the same in rat with deficiency of vital energy or qi stagnation, and Tongxinluo could regulate the disorder of the gene expression, protecting vascular endothelium from injure.

Effect of dopamine on vascular reactivity in near-term lamb carotids: role of the endothelium.

Many neonates are diagnosed with hypotension in the first 24 hr of life. Those with severe hypotension are often given high doses of dopamine at 10 to 20 microg/kg/min. This study examined the hypothesis that dopamine, a vasoactive drug commonly used in the neonatal intensive care unit, alters vascular reactivity. Vascular reactivity was measured by comparing 5HT dose-response characteristics in untreated near-term lamb common carotid arteries and arteries treated with 15 microg/kg/min of dopamine. The authors found that dopamine pretreatment for 60 min significantly potentiated 5HT-induced contractile tone by approximately 100% ( p < .05). This observed increase in tone was accompanied by a significant decrease in the affinity of 5HT to its receptor ( p < .05), suggesting an activation of a separate contractile pathway, or a mechanism downstream from agonist-receptor binding. Interestingly, an increase in contractility was observed only in endothelium-intact arteries. In arteries with denuded endothelium, dopamine pretreatment resulted in a small but significant decrease in tone compared to control arteries ( p < .05), suggesting a vasodilatory mechanism unmasked by endothelium removal. Although multiple mechanisms can increase vascular resistance, these data described the in vitro effects of high doses of dopamine on vascular tone as well as the role of the endothelium in dopaminemediated vasoconstriction.

Combination therapy with cerivastatin and nifedipine improves endothelial dysfunction after balloon injury in porcine coronary arteries.

HMG-CoA reductase inhibitors and calcium channel blockers have antiatherogenic effects; however, their mechanisms remain to be elucidated. This study examined the effect of cerivastatin and/or nifedipine on the endothelial dysfunction in porcine balloon-injured coronary arteries. Normal male pigs were randomly divided into the following four groups: control, cerivastatin (1 mg/kg/d PO), nifedipine (4 mg/kg/d PO), and their combination (n = 10 each). We started the treatments 3 days before balloon injury in the proximal left coronary arteries and continued for 4 weeks after the procedure. Then, we examined endothelial vasodilator functions ex vivo in organ chambers and in vitro by Western blotting for eNOS expression. Endothelium-dependent relaxations to serotonin, but not those to bradykinin or the calcium ionophore A23187 or endothelium-independent relaxations to sodium nitroprusside, were significantly impaired by balloon injury. The monotherapy with cerivastatin or nifedipine partially improved, and their combination supernormalized the relaxations to serotonin without affecting those to bradykinin or A23187 or endothelium-independent relaxations to sodium nitroprusside. The expression of eNOS was significantly reduced by balloon injury and normalized by the combination therapy. These results indicate that the combination therapy improves endothelial dysfunction after balloon injury, in which the up-regulation of eNOS may be involved.

Angiotensin receptor blockade with candesartan attenuates atherosclerosis, plaque disruption, and macrophage accumulation within the plaque in a rabbit model.

BACKGROUND: Little is known about whether direct angiotensin receptor blockade can reduce atherosclerosis and plaque disruption. This study evaluated the effect of angiotensin receptor blockade on both the development of atherosclerosis and the disruption of plaque in a modified Constantinides animal model. METHODS AND RESULTS: Twenty-eight New Zealand White rabbits underwent aortic balloon injury followed by a 1% cholesterol diet for 8 weeks. Thirteen rabbits received candesartan at 0.5 mg x kg(-1) x d(-1) beginning 2 days before aortic balloon injury and continued for the total 8 weeks of the cholesterol diet. The rabbits were then pharmacologically triggered and humanely killed, and their aortas were analyzed. The degree of atherosclerosis was determined by intima-media ratio of the infrarenal portion of the aorta. The frequency of intra-aortic thrombosis, a measure of plaque disruption, and the percentages of macrophage area and collagen-staining area of the plaque were determined. Candesartan-treated rabbits had less atherosclerosis (intima-media infrarenal aorta ratio of 1.18+/-0.08 versus 1.57+/-0.08 [mean+/-SEM] for the placebo group, P<0.001); fewer thrombi (3 of 13 versus 11 of 15; P<0.05); lower percentage area of macrophages to total plaque (18.8+/-2.7% versus 27+/-2.5%, P<0.05); and higher collagen to total plaque area (45+/-3% versus 35+/-2%, P<0.01). CONCLUSIONS: These results demonstrate that angiotensin receptor blockade attenuates the degree of atherosclerosis and reduces both plaque disruption and macrophage accumulation while increasing collagen deposition in the aortas of this animal model.

Nerve growth factor supplementation reverses the impairment, induced by Type 1 diabetes, of hindlimb post-ischaemic recovery in mice.

AIMS/HYPOTHESIS: Type 1 diabetes increases the risk of peripheral ischaemia and impairs recovery once ischaemia occurs, probably because the healing process is hampered by diabetes-induced endothelial dysfunction. In normoglycaemic mice subjected to limb ischaemia, blockade of nerve growth factor (NGF) compromises reparative angiogenesis. In the present study, we evaluated if expressional alterations of endogenous NGF system components are associated with diabetes-related impairment in neovascularisation. In addition, we tested whether the correction of NGF liabilities benefits post-ischaemic healing of Type 1 diabetic animals. METHODS: Unilateral hindlimb ischaemia was produced in streptozotocin-induced Type 1 diabetic mice. Purified murine NGF (20 microg daily for 14 days) or PBS were injected into ischaemic adductors. Non-diabetic mice given PBS served as controls. Hindlimb blood flow was analysed sequentially for up to 14 days. At necroscopy, adductors were removed for quantification of microvessel density, endothelial cell apoptosis and NGF receptor expression. NGF content was determined by ELISA three days after ischaemia. In vitro, we tested whether NGF protects endothelial cells from apoptosis induced by high glucose and whether vascular endothelial growth factor-A (VEGF-A) is involved in this beneficial effect. RESULTS: Muscles removed from Type 1 diabetic mice showed reduced NGF content and up-regulation of the NGF p75 receptor. NGF supplementation promoted capillarisation and arteriogenesis, reduced apoptosis, and accelerated blood flow recovery. NGF stimulated VEGF-A production by human endothelial cells incubated in high-glucose medium and conferred resistance against high-glucose-induced apoptosis via a VEGF-A-mediated mechanism. CONCLUSIONS/INTERPRETATION: NGF protects endothelial cells from apoptosis induced by Type 1 diabetes and facilitates reparative neovascularisation. The findings may open up new therapeutic options for the treatment of diabetic complications.

Evidence for the mechanisms underlying the effects of pimaradienoic acid isolated from the roots of Viguiera arenaria on rat aorta.

The present study examines the effects of the diterpene ENT-pimara-8(14),15-dien-19-oic acid (PA) on rat thoracic aorta. PA (10(-5), 3 x 10(-5) and 10(-4) mol/l) caused concentration-dependent inhibition of phenylephrine (Phe)-induced contraction in either endothelium-intact or endothelium-denuded aortic rings. PA attenuated the contraction induced by CaCl(2) in Ca(2+)-free solution containing Phe (10(-7) mol/l) or KCl (30 mmol/l). This diterpene did not interfere with Ca(2+) release from intracellular stores mediated by either Phe (10(-6) mol/l) or caffeine (30 mmol/l). PA (10(-6) to 3 x 10(-4) mol/l) concentration dependently relaxed Phe-pre-contracted rings with intact (92.64 +/- 7.60%) or denuded endothelium (98.82 +/- 1.56%). Pre-incubation of denuded aortic rings with N(G)-nitro-L-arginine methyl ester (10(-4) mol/l), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (10(-6) mol/l) or indomethacin (10(-5) mol/l) reduced PA-induced relaxation (percentage of relaxation: 77.50 +/- 3.95, 78.56 +/- 2.81, 77.11 +/- 6.22, respectively). However, the relaxant responses induced by PA on Phe-pre-contracted rings were unaffected by tetraethylammonium (1 and 5 mmol/l). PA also relaxed KCl-pre-contracted rings with intact (97.44 +/- 3.66%) or denuded endothelium (95.95 +/- 3.72%). Collectively, these results support the notion that the effects elicited by PA on vascular smooth muscle are endothelium-independent and involve extracellular Ca(2+) influx blocked. In addition, PA effects are partly dependent on the release of nitric oxide from the vascular smooth muscle through an activation of guanylyl cyclase-dependent mechanism and are related to the release of metabolites derived from the arachidonic acid pathway. Finally, our results demonstrated that the PA relaxant action is not related with the opening of potassium (K(+)) channels.

Ginsenoside Rg3 inhibits phenylephrine-induced vascular contraction through induction of nitric oxide synthase.

Ginsenoside Rg3 (Rg3) isolated from Panax ginseng relaxes vessels and exerts a cytoprotective effect. In view of the fact that nitric oxide (NO) is involved in vascular hyporeactivity and immunostimulation, the effects of total ginsenosides (GS) and Rg3 on the vascular responses and the expression of inducible nitric oxide synthase (iNOS) were investigated. Vasocontraction of endothelium-denuded aortic ring was induced by phenylephrine with or without GS or Rg3. The expression of iNOS was assessed by Western blot and RT-PCR analyses. NF-kappaB activation was monitored by gel shift, immunoblot and immunocytochemical analyses. Incubation of the endothelium-denuded aortic ring with GS or Rg3 inhibited phenylephrine-induced vasocontraction, which was abrogated by NOS inhibition. GS or Rg3 increased NO production in aortic rings, but Rb1, Rc, Re and Rg1 had no effect. Aortic rings obtained from rats treated with GS or Rg3 responded to phenylnephrine to a lesser extent, while producing NO to a larger extent, than those from control animals. GS or Rg3 induced iNOS in vascular smooth muscle. Rg3 induced iNOS with increase in NO production in Raw264.7 cells. Rg3 increased NF-kappaB DNA binding, whose band was supershifted with anti-p65 and anti-p50 antibodies, and elicited p65 nuclear translocation, which was accompanied by phosphorylation and degradation of I-kappaBalpha. PKC regulated iNOS induction by Rg3. In conclusion, Rg3 relaxes vessels as a consequence of NO production, to which iNOS induction contributes, and iNOS induction by Rg3 accompanied NF-kappaB activation, which involves phosphorylation and degradation of I-kappaBalpha and nuclear translocation of p65.

Three vehicle formulations for melagatran, a direct thrombin inhibitor, evaluated in a vena cava thrombosis model in the rat.

BACKGROUND: The objective of this study was to investigate whether the use of a depot formulation would enhance the antithrombotic effect of the direct thrombin inhibitor melagatran. METHODS AND RESULTS: In a rat venous thrombosis model, animals were openly randomized to receive subcutaneously (s.c.) either vehicle (saline, cyclodextrin or poloxamer) or melagatran (0.5 microM/kg) dissolved in vehicle. An additional injection of cyclodextrin or poloxamer was given at another site to investigate whether the vehicle itself had any additional effect. All injections were given 30 min before induction of thrombus formation. Thrombus formation was induced by ferric chloride, together with stenosis of the caval vein, during a short period of inhalation anaesthesia. Five hours later the thrombi were harvested and their wet weight determined. Thrombus size was comparable across the vehicle-only groups. The antithrombotic effects of melagatran in saline or poloxamer were comparable while melagatran in cyclodextrin was less effective. The effects of melagatran in saline, cyclodextrin or poloxamer were not enhanced by additional cyclodextrin or poloxamer. Thrombin time (TT) and activated partial thromboplastin time (aPTT) at the end of the experiment were prolonged to a greater extent in the groups receiving melagatran in cyclodextrin or poloxamer compared with those receiving melagatran in saline. CONCLUSION: In this vena cava thrombosis model, no enhanced antithrombotic effect was observed with melagatran given as a s.c. depot formulation in cyclodextrin or poloxamer compared with that in saline.

Effects of traditional Chinese formulations on rat carotid artery injured by balloon endothelial denudation.

We examined the inhibitory effects of traditional Chinese formulations (TCFs: Kampo formulation in Japanese) on intimal thickening of the carotid artery injured by balloon endothelial denudation in rats. Among the eight TCFs examined oren-gedoku-to (huanglian-jiedu-tang in Chinese), choto-san (diao-teng-san), saiko-ka-ryukotsu-borei-to (chaihujia-longgu-muli-tang) and dai-joki-to (da-cheng-qi-tang) significantly inhibited the intimal thickening 7 days after denudation. These four TCFs also inhibited proliferation of vascular smooth muscle cells (VSMC), which may play a central role in the development of restenosis after balloon endothelial denudation. The present results suggest that further evaluation of these four TCFs as inhibitors of VSMC proliferation to prevent arteriosclerosis is warranted.

Evaluation of DNA aptamers directed to thrombin as potential thrombus imaging agents.

Two DNA aptamers directed against two separate exosites on human alpha-thrombin were evaluated for thrombus-imaging potential. Aptamer ODN 1 is directed to the thrombin substrate binding site (exosite 1). Our finding that ODN 1 competes with fibrin for binding to exosite 1 on thrombin suggests that ODN 1 will not be useful for thrombus imaging. Aptamer ODN 2 is directed against the thrombin heparin binding site (exosite 2). ODN 2 bound to model thrombi that were formed either by clotting purified fibrinogen with thrombin, or by recalcifying citrated plasma. As the thrombin content of thrombi was increased the rate of ODN 2 uptake into preformed thrombi increased, whereas the rate of release of ODN 2 out of preformed thrombi decreased. This in vitro data suggested that ODN 2 might be useful for thrombus imaging because it can bind to exosite 2 on fibrin-bound thrombin. However, in a rabbit jugular vein model using thrombus supplemented with human thrombin, ODN 2 uptake was equal to the ovalbumin control, and did not reflect thrombin content. While the in vitro results with ODN 2 were consistent with thrombus imaging, the rapid clearance of ODN 2 from circulation, combined with slow mass transfer in the clot, seem to work against in vivo thrombin-dependent imaging or washout analysis.

Preventive effects of a traditional Chinese formulation, Chaihu-jia-Longgu-Muli-tang, on intimal thickening of carotid artery injured by balloon endothelial denudation in rats.

We report here that the traditional Chinese formulation, Chaihu-jia-Longgu-Muli-tang (CLM), significantly inhibited the increase in intimal thickening in rat carotid artery injured by balloon endothelial denudation, which mimics many aspects of restenosis after percutaneous coronary intervention (PCI) in humans. CLM, Saiko-ka-Ryukotsu-Borei-to in Japanese, is commonly prescribed for symptoms accompanying hypertension and atherosclerosis in Japanese Kampo medical care. CLM administered orally 1 week before and 1, 4 and 8 weeks after balloon injury inhibited the increase in intimal area, intimal/medial ratio and stenosis ratio. To our knowledge, this is the first report demonstrating inhibitory effects of a traditional Chinese formulation on intimal thickening of carotid artery after balloon injury. It is worth noting that CLM maintained its inhibitory effect up to 8 weeks after balloon injury. The reduction in intimal thickening by CLM could have resulted from inhibition of intimal smooth muscle cell proliferation, which was assessed by immuno-histochemical analysis using monoclonal antibody against proliferating cell nuclear antigen. Therefore, CLM may be a favourable candidate for prevention of restenosis after PCI. Moreover CLM may have a therapeutic value in the prevention of atherosclerosis, because restenosis after PCI is considered to be an accelerated atherosclerosis.

The role of alpha(v)beta3 integrins in vascular healing.

Alpha(v)beta3 integrins play an important role in vascular healing. Vascular injury is a stimulus for expression of alpha(v)beta3 by vascular cells and, among other effects, alpha(v)beta3 integrins function in the adhesion of activated platelets to endothelium. white cell/endothelium interactions, platelet-mediated thrombin generation, fibrin clot retraction by nucleated cells, smooth muscle cell (SMC) migration and proliferation, vascular cell apoptosis, and vascular remodeling. There are ten different animal models in which treatment with alpha(v)beta3 antagonists reduced the vascular response, including (neo)intima formation, after mechanical injury. These studies, along with mechanistic data derived from cell culture studies, provide compelling evidence that alpha(v)beta3 integrins are involved in vascular repair processes. The challenge is to develop a therapeutic agent that will prove effective in reducing restenosis in humans following percutaneous coronary intervention (PCI).

Coronary artery endothelial protection after local delivery of 17beta-estradiol during balloon angioplasty in a porcine model: a potential new pharmacologic approach to improve endothelial function.

OBJECTIVES: The goal of this research was to study the effect of locally delivered 17beta-estradiol (17beta-E) during angioplasty on endothelial function after percutaneous transluminal coronary angioplasty (PTCA) at four weeks. BACKGROUND: The endothelium plays a major role in the structural and functional integrity of coronary arteries and is damaged by PTCA. METHODS: Juvenile swine were subjected to PTCA, after which each artery was randomly-assigned to 600-microg 17beta-E delivered locally, an equal volume of vehicle (V) or PTCA alone. After four weeks, the improvement in endothelial function was assessed by angiography using intracoronary acetylcholine (Ach) infusion and by immunohistochemistry. RESULTS: At 10(-5) mol/l and 10(-4) mol/l Ach, significant vasoconstriction was noted in arteries treated with PTCA alone (p < 0.01 and p < 0.0001, respectively) and with PTCA plus V (p < 0.02 and p < 0.001, respectively). No significant vasoconstrictive response to Ach was observed in arteries treated with PTCA plus 17beta-E. Immunohistochemistry of vessels four weeks after PTCA revealed enhanced re-endothelialization (p < 0.0005) and endothelial nitric-oxide synthase (eNOS) expression (p < 0.0005) in PTCA plus 17beta-E-treated arteries compared with the other two treatment groups. Arteries treated with 17beta-E showed significantly lower neointima formation, which correlated inversely with the extent of re-endothelialization and eNOS expression. CONCLUSIONS: Locally delivered 17beta-E significantly enhances re-endothelialization and endothelial function after PTCA, possibly by improving the expression of eNOS. Since endothelial dysfunction can promote both restenosis and coronary spasm, local 17beta-E administration is a promising new approach to improve long-term results after PTCA.