Atorvastatin suppresses vascular hypersensitivity and remodeling induced by transient adventitial administration of lipopolysaccharide in rats.

BACKGROUND: The phenotypic transition of vascular smooth muscle cells (VSMCs) from a contractile to a proliferative state markedly affects the pathophysiology of cardiovascular diseases. The adventitial inflammation can promote neointimal formation and vascular remodeling. We used direct administration of lipopolysaccharide (LPS) into the periphery of the carotid artery to investigate the influence of transient adventitial inflammation on vascular remodeling and its potential mechanism. METHODS: Male 15-week-old Wistar rats were randomly assigned to four groups with six rats in each group. The rats of groups I and II were administered distilled water, and group III and IV were treated with fasudil and atorvastatin respectively. All treatments were given daily for 11 days. On day 8, the adventitia in group I was injected with 5 µL sterile saline, and the group II-IV were injected with 5 µL sterilized LPS. The carotid blood flow and femoral blood pressure were measured in vivo, and the thickness of vascular intima and middle layer was measured in vitro. Serum interleukin-6 (IL-6) and tumor necrosis factor α (TNFα) were determined using enzyme-linked immunosorbent assay (ELISA) assay. And the Rho-associated coiled-coil-containing protein kinase 2 (ROCK2), myosin phosphatase target subunit 1 (MYPT1), myosin light chain (MLC), myocardin, SM-α actin or glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were detected by western blot. The comparisons were made by one-way analysis of variance with Bonferroni's post hoc test. A value of P<0.05 was considered to represent a statistically significant difference. RESULTS: Transient adventitial inflammation induced by LPS caused no obvious change in basal blood flow, but did lead to vascular hypersensitivity to serotonin. Morphological examinations revealed that the medial layer was the only domain affected, and showed VSMC proliferation and rearrangement. LPS increased serum IL-6 and TNFα contents, ROCK2 expression and activity, and caused changes in the expression levels of some stereotypical VSMC genes. Similar to the Rho-kinase inhibitor fasudil, atorvastatin completely restored the morphological alterations, even increased blood flow. CONCLUSIONS: Our study confirms the beneficial effect of atorvastatin on the vascular system in terms of morphology and function.

Statin-ezetimibe versus statin lipid-lowering therapy in patients with acute coronary syndromes undergoing percutaneous coronary intervention.

BACKGROUND: Studies comparing the clinical efficacy and safety of intensive statin therapy with ezetimibe-statin combination therapy are still rare at present, especially in Asian population. METHODS: We enrolled 202 patients who suffered acute coronary syndrome (ACS) and underwent percutaneous coronary intervention (PCI) between May and July in 2016. Patients were allocated into three groups based on the lipid lowering strategy: moderate-intensity statin group (n=118), ezetimibe combined with moderate-intensity statin group (ezetimibe-statin combination, n=55) and intensive statin group (n=29). The lipid profiles and side effects were analyzed and compared among the patients in three groups at admission, 1 month and 3 months after PCI. The clinical outcomes of the patients were observed through 6-month follow-up. RESULTS: One month after PCI, the level of non-high density lipoprotein-cholesterol (non-HDL-C) was decreased by 41.9%, 21.6% and 29.8% by ezetimibe-statin combination therapy, moderate-intensity statin therapy and intensive statin therapy, respectively (P<0.05). The reduction percentages of TC and LDL-C were significantly higher in ezetimibe-statin combination group than in moderate-intensity statin group (P<0.001). The proportion of patients reaching LDL-C goal was higher in ezetimibe-statin combination group (69.1%, P=0.007) and intensive statin group (67.9%, P=0.047) compared with moderate-intensity statin group (46.9%) at 1 month after PCI. There was no significant difference among the three groups with respect to hepatic enzymes level, creatine kinase (CK) level and incidence of muscle symptoms. CONCLUSIONS: The reduction percentage of non-HDL-C was larger in ezetimibe-statin combination group than intensive statin group. This finding suggested that statin/ezetimibe combination therapy could be an alternative to intensive statin therapy in Chinese patients with atherosclerotic cardiovascular disease.

Efficacy and safety of ticagrelor versus clopidogrel with different dosage in high-risk patients with acute coronary syndrome.

BACKGROUND: Dual antiplatelet therapy is recommended as a standard antiplatelet strategy in acute coronary syndrome. For those with reduced pharmacologic response to clopidogrel, strengthening antiplatelet therapy (clopidogrel 150mg daily) may reduce adverse clinical events. Ticagrelor is a direct-acting inhibitor of the adenosine diphosphate receptor P2Y12 that has a more rapid onset and offset than clopidogrel. METHODS: In this retrospective study, we compared ticagrelor (180mg loading dose 90mg twice daily thereafter), clopidogrel (300mg loading dose, 75mg or 150mg daily thereafter) for the prevention of cardiovascular events in 273 high-risk patients admitted to coronary care unit with acute coronary syndrome. RESULTS: The rate of IST in hospital was significantly reduced in patients of ticagrelor group comparing with those receiving clopidogrel 75mg (0.69% vs 8.2%, p=0.009). Moreover, the TVR rate was less in the ticagrelor group than clopidogrel 75mg group (2.7% vs 13.1%, p=0.007) 6months follow-up. The incidence of MACCE has no difference between the two clopidogrel groups. Kaplan-Meier analysis of MACCE-free indicated that there was no difference between the three groups. Ticagrelor significantly increased the rate of minor bleeding compared with clopidogrel 75mg daily during hospital (45.5% vs 26.2%,p=0.012) and 6-month follow-up (66.9% vs 45.9%,p=0.004).Bleeding-free prognosis was significantly better in the clopidogrel 75mg daily group. CONCLUSIONS: In patients with acute coronary syndrome undergoing PCI, the rate of in-stent thrombosis and TVR were significantly reduced treated with ticagrelor compared with clopidogrel 75mg daily, without an increase of overall major bleeding, but with an increase of minor bleeding.

[Effect of valsartan on vasoconstriction induced by the chronic injury of the adventitia in the rat collared carotid artery].

OBJECTIVE: Vasoconstriction and vascular hypersensitivity to serotonin were previously shown in animal models of adventitia injury. We investigated the contribution of angiotensin II (AngII)/AngII receptors and oxidative stress to vascular contractility and reactivity in this model. METHODS: Wistar Kyoto rats were divided into 3 groups: normal (n = 6, no any intervention, only for measuring the serum AngII concentration), vehicle (n = 12, collared), and valsartan (n = 12, collared + valsartan 30 mg×kg(-1)×d(-1)). After one week of treatment, adventitia injury was induced by positioning a silicone collar around the right carotid artery for one week. Blood flow and vascular reactivity to serotonin were determined one week after injury, the blood from left ventricle was taken to measure the serum AngII concentration by ELISA, and carotids were harvested for morphometry and Western blot analysis. RESULTS: Adventitia injury induced lumen cross-sectional area reduction (-44% vs. -5%), media diameter increase (62% vs. 10%), blood flow reduction [(2.79 ± 0.22) vs. (4.33 ± 0.84) ml/min] were significantly attenuated by valsartan. The increased vascular reactivity sensitivity to serotonin in vehicle group was also significantly reduced in valsartan group. Serum AngII concentration was significantly increased in vehicle group [(45.21 ± 4.52) pg/ml vs. (19.83 ± 0.5) pg/ml in normal rats, P = 0.0148] and the expression of AngII type 1 (AT(1)) receptor, AngII type 2 (AT(2)) receptor, as well as p22(phox) in collared arteries were significantly upregulated. Valsartan did not affect the AT(1) receptor expression but further increased serum AngII concentration [(89.73 ± 20.44) pg/ml vs. (45.21 ± 4.52) pg/ml, P = 0.001], and AT(2) receptor expression, while downregulated p22(phox) expressions. CONCLUSIONS: Collar-induced adventitia injury resulted in chronic vasoconstriction and vascular hypersensitivity to serotonin via increased serum AngII level, upregulated AngII receptors expression in the vascular well, and activated local oxidative stress. These changes could be blocked by valsartan suggesting a crucial role of AngII/AngII receptors on vascular contractility and reactivity changes in this model.

Inflammation inhibitory effects of sirolimus and paclitaxel-eluting stents on interleukin-1ß-induced coronary artery in-stent restenosis in pigs.

BACKGROUND: Coronary artery in-stent restenosis (ISR) and late stent thrombosis remain as important complications of stenting. The inflammation reactions to sirolimus and paclitaxel-eluting stents were investigated in a swine stenosis model induced by interleukin (IL)-1ß. METHODS: Mini pigs (n = 12; 2-3 months old and weighing 25-30 kg) were subjected to thoracotomy. Segments (10 mm) of the mid left anterior descending coronary artery and left circumflex coronary artery were exposed and aseptically wrapped with a cotton mesh soaked with IL-1ß (5 µg). After 2 weeks, the animals were anesthetized and quantitative coronary arteriography (QCA) was performed. The stenosis sites were randomized into three groups for stent insertion: a sirolimus-eluting stent (SES) group (Firebird(TM), n = 7), a paclitaxel-eluting stent (PES) group (TAXUS(TM), n = 9), and a bare-metal stent (BMS) group (YINYITM, Dalian Yinyi Biomaterials Development Co., Ltd, China, n = 8). The three different stents were randomly implanted into stenosis segments. Expression of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), P-selectin and vascular cell adhesion molecule-1 (VCAM-1) was determined by reverse transcription-coupled polymerase chain reaction (RT-PCR). RESULTS: QCA showed severe stenosis in IL-1ß treated segments. The SES and PES groups showed lower 1-month angiographic late lumen loss (LLL) within the stent and the lesion compared with BMS (P < 0.05) by follow-up QCA. The SES showed lower LLL than that of PES in reducing 1-month inflammation lesions in pigs by follow-up QCA ((0.15 ± 0.06) mm vs. (0.33 ± 0.01) mm, P < 0.0001). The neointimal hyperplasia areas in SES and PES showed lower than those of BMS (SES (11.6 ± 1.7) mm(2), PES (27.2 ± 1.6) mm(2) vs. BMS (76.2 ± 1.3) mm(2), P < 0.0001). The mRNA expression of MCP-1 by RT-PCR in SES and PES showed lower than that of BMS at 30 days after stenting (SES 0.20 ± 0.03, PES 0.48 ± 0.49 vs. BMS 0.58 ± 0.07, P < 0.05). Levels of VCAM-1 in SES were significantly lower than those of PES and BMS (SES 0.35 ± 0.08 vs. PES 0.65 ± 0.13, BMS 0.70 ± 0.06, P < 0.05). Histochemical immunostaining of vessel walls showed lower inflammatory chemokine MCP-1 expression in the SES and PES groups compared with BMS. CONCLUSION: SESs were superior in reducing 1-month angiographic LLL in inflammation lesions in pigs, strongly suggesting that SESs can suppress inflammatory reactions in ISR at multiple points.

Effect of tongxinluo on vasoconstriction induced by the chronic injury of the adventitia in the rat carotid artery.

OBJECTIVE: Tongxinluo (TXL) is a traditional Chinese medicine that is developed on the meridian theory of traditional Chinese medicine, with the function of alleviating the angina. The present study was undertaken to explore the molecular mechanism of TXL in treating the pectoris angina through observing the effectiveness of TXL superfine powder on the vasoconstriction and the activation of RhoA/Rho-kinase pathway induced by the injury of the adventitia. METHODS: 36 male Wistar Kyoto rats were assigned to 3 treatments (n=12): vehicle, TXL (400 mg kg(-1) day(-1)) and fasudil (15 mg kg(-1) day(-1)). After 1 week of treatment, adventitia injury was induced by positioning a silicone collar around the right carotid artery for 1 week. Blood flow and vascular reactivity to serotonin were determined 1 week after injurying, the both sides of carotids were harvested for morphometry, Western blotting analysis and RT-PCR analysis. RESULTS: Adventitia injury leaded to histological changes of vasoconstriction with the lumen cross-sectional area of 44.7% (p<0.001) decreasing and the media diameter of 62.31% (p<0.001) increasing, accompanying by the reduction of the blood flow and the increase of vascular reactivity sensitivity to serotonin. Treatment with both TXL superfine powder and fasudil can prevent the development of vasoconstriction, improve the carotid blood flow and normalize the vascular hypersensitivity to serotonin. Adventitia injuring of the rat carotid increased the expression of Rho-kinase mRNA and p-MYPT1(Thr696) protein by 1.78-fold (p<0.05) and >2-fold respectively (p<0.05). TXL reduced the expression of Rho-kinase mRNA and p-MYPT1(Thr696) protein by 54.2% (p<0.05) and 57.1% (p<0.05) respectively in collared arteries. Fasudil restrained the p-MYPT1(Thr696) protein expression by 63.8% (p<0.05) in collared arteries, did not affect the collar-induced the increase of Rho-kinase mRNA expression (p>0.05). CONCLUSIONS: Treatment with TXL, similar to that with fasudil, can effectively prevent collar-induced vasoconstriction and vascular hyperreactivity to serotonin through inhibiting the RhoA/Rho-kinase pathway.

[Inhibitory effect and acting mechanism of Tongxinluo on IL-1beta-mediated coronary intimal hyperplasia and 5-hydroxytryptamine-induced coronary vasospasm in small swine].

OBJECTIVE: To observe the inhibitory effect of Tongxinluo (TXL) on coronary vaso spasm in small swine in vivo, and to investigate its possible acting mechanism. METHODS: The model of coronary atherosclerosis in 16 male small swines was established by left thoracotomy after anesthesia, isolated the sections of left anterio-descending branch and proximal end of rotator branch with similar outer diameter, and encapsulated them with paper-towel holding 2.5 microg interleukin-1beta. Two weeks later, the condition of coronary vasospasm induced by catheter intra-coronary injection of 5-hydroxytryptamine (5-HT, 10 microg/kg) was observed through coronary artery contrast examination. The 12 swines with successfully formed coronary vaso spasm were randomly divided into 2 groups, the TXL group and the control group. They were fed with special diet, but TXL 1 g/(kg d) was administered additionally to the TXL group for 4 weeks. The observation on coronary vasospasm was repeated 1 week after discontinuation of TXL treatment, then the animals were sacrificed, their vascular sections enclosed with IL-1beta was taken to conduct the pathologic examination and to detect the expressions of Rho kinase mRNA and its substrate myosin- binding subunit phosphorylation (MBS-P) by RT-PCR and Western blot method. RESULTS: Coronary artery contrast showed that local coronary stenosis occurred in the 12 model swines to different extents (20% - 30%, and vascular spasm on them could be induced by 5-HT. At the time of repeating examination, 11 vascular sections in the control group still maintain their positive spasm reaction to 5-HT, but only 2 in the TXL group did so, the reaction turned to negative in 1 and 10 in the two groups respectively. Pathological examination showed that different degrees of macrophage aggregation could be found in both groups. The degree of lumen stricture and endometrial hyperplasia in the TXL group was obviously attenuated than those in the control group. The expressions of Rho kinase mRNA and MBS-P in the control group were up-regulated obviously. As compared with those in the control group, they were inhibited significantly in the TXL group, as (71.5 +/- 2.4) vs (98.2 +/- 7.7)% and 16,633 +/- 1,390 vs 25,818 +/- 4,745, respectively (all P < 0.05). CONCLUSION: TXL could obviously inhibit the coronary intimal hyperplasia mediated by IL-1beta and coronary vasospasm induced by 5-HT, one of its mechanisms is possibly the inhibition on the intracellular Rho kinase mRNA expression in the IL-1beta enclosed vascular section to decrease the level of MBS-P.

[Effects of rapamycin on Rho-kinase and p27 mRNA expressions in a porcine coronary intimal proliferation model induced by interleukin-1beta].

OBJECTIVE: To observe the effects of rapamycin on the expressions of Rho-kinase and p27 mRNA during vascular intimal proliferation in a porcine model of coronary stenosis induced by interleukin-1beta (IL-1beta). METHODS: The proximal segments of LAD and LCX were wrapped with cotton mesh that had absorbed sepharose bead solution with or without IL-1beta. Selective coronary angiography was performed two weeks later and the animals were killed for collecting the samples for histopathology and RT-PCR analyzing of Rho-kinase and p27 mRNA. RESULTS: The expressions of Rho-kinase and p27 mRNA could be visualized in normal coronary wall. The expression of Rho-kinase mRNA was significantly enhanced and the expression of p27 mRNA was significantly decreased during the process of intimal proliferation induced by IL-1beta. Rapamycin significantly inhibited the intimal proliferation, reduced the infiltration of inflammatory cells, reduced the expression of Rho-kinase mRNA and increased the expression of p27 mRNA. CONCLUSIONS: The expression of Rho-kinase mRNA is upregulated and p27 mRNA downregulated in coronary artery stenosis induced by IL-1beta and these effects could be abolished by cotreatment with rapamycin.

[Upregulated Rho-kinase and increased phosphorylation of myosin-binding subunit of myosin phosphates are key players in a porcine coronary artery spasm model with interleukin-1beta].

OBJECTIVE: Phosphorylation of myosin light chain (MLC) is one of the most important steps for vascular smooth muscle contraction and Rho-kinase is involved in this process. We investigated the role of Rho-kinase in a porcine coronary artery spasm model with interleukin-1beta. METHODS: Segments of left coronary artery adventitia were surrounded by normal saline (n = 8) or IL-1beta agarose microne (n = 8) for 2 weeks. Vasospastic responses to intracoronary serotonin or histamine then studied at the saline or IL-1beta-treated site. The Rho-kinase mRNA expression in the treated site was measured by reverse transcription-polymerase chain reaction analysis (RT-PCR). The extent of phosphorylation of myosin-binding subunit of myosin phosphates (MBS, one of the major substrates of Rho-kinase) were quantified by Western blot analysis. RESULTS: Intracoronary serotonin or histamine repeatedly induced coronary artery spasm and coronary arterial stenosis was evidenced at IL-1beta-treated site. Expression of Rho-kinase mRNA in IL-1beta-treated site was significantly increased compared to saline treated site (98.20% +/- 7.66% vs. 63.70% +/- 4.26%, P < 0.05). Western blot analysis showed that during the serotonin-induced contractions the extent of phosphorylation of MBS was also significantly increased in the spastic site (25,485 +/- 4745 vs. 6510 +/- 779, P < 0.05). CONCLUSION: Rho-kinase upregulation at the spastic site and increased phosphorylation of myosin-binding subunit of myosin phosphates are key players in inducing vascular smooth muscle hypercontraction in this porcine model.