Effects of alprostadil in β-aminopropanitrile induced aortic dissection in a murine model / 中华心血管病杂志

Objective: To investigate the protective role of alprostadil on aortic dissection. Methods: 26 C57BL6 male mice were divided into control group (normal drinking water, n=13) and model group (1 g·kg-1·d-1 BAPN via drinking water, n=13). On day 14, mRNA expression of inflammatory-related genes as well as EP receptor families were detected by RT-PCR (n=6 each) and EP4 protein levels were determined by Western blot (n=7 each). Another 88 mice were divided into 3 groups: control group (n=22), model group (n=33) and treatment group (n=33). The mice in model group and treatment group were applied with BAPN (1 g·kg-1·d-1) via drinking water. The mice in treatment group received additional intraperitoneal injection with alprostadil (80 μg·kg-1·d-1) for 28 days. The mice in the control and model group received equal volume intraperitoneal injection with 0.9% saline respectively. The body weight and systolic blood pressure, the mortality and morbidity were monitored from the beginning until the designed end of the study. On day 28, the mice were sacrificed and aorta were fixed, embedded and sliced, followed by staining with HE and Victoria Blue. The distribution of EP4 was determined by immunohistochemistry in control (n=6) and model group (n=6). Furthermore, the concentration of PGE1 were tested among model (n=3) and treatment group (n=4). EP4 protein expression was determined in model group (n=7) and treatment group (n=6). Results: On day 14, mRNA expression level of MCP-1 ((2.74±1.55) vs. (1.00±0.49),<0.05) and MMP2((1.38±0.42) vs. (1.00±0.27), P<0.05) was significantly upregulated in model group compared with control group. Protein expression of EP4 receptor also increased in aorta in model group compared with control group (1.48±0.51 vs. 1.00±0.19, P<0.05). In the dissection area, the EP4 expression was also enriched compared with non-dissection area, particularly in endothelial cells and inflammatory cells on day 28. BAPN applied in drinking water (model and treatment groups) successfully induced the aortic dissection in mice, some mice died of the rupture. The elastic fibers were fractured, and the infiltrated immune cells were visible in dissected tissue. False lumen was formed. There was no dissection and death in the control group. Compared with control group, the morbidity and mortality rates were significantly increased in the model group (60.6%, 20/33, 30.3%, 10/33) and the treatment group (72.7%, 24/33, 24.2%, 8/33). The mortality and morbidity rates were similar between model and treatment groups. There is no difference in terms of SBP among three groups (P>0.05). Further study showed that after alprostadil injection, the blood concentration of PGE1 was increased in treatment group ((0.540±0.041 vs. 0.436±0.012)μmol/L, P<0.05). Besides, the EP4 receptor expression was downregulated in the treatment group compared to model group (0.60±0.30 vs. 1.00±0.20, P<0.05). Conclusion: EP4 expression is upregulated in BAPN induced aortic dissection mouse model. No protective effects are observed post alprostadil treatment in this model probably due to the reduced expression of EP4.

Asymmetric Dimethylarginine Predicts One-year Recurrent Cardiovascular Events: Potential Biomarker of "Toxin Syndrome" in Coronary Heart Disease / 中国结合医学杂志

OBJECTIVE@#To examine the prognostic value of serum levels of asymmetric dimethylarginine (ADMA) in patients with stable coronary heart disease (CHD) thus explore a potential biomarker of "toxin syndrome" in CHD.@*METHODS@#In this prospective nested case-control study, 36 of 1,503 Chinese patients with stable CHD experienced at least 1 recurrent cardiovascular event (RCE) during 1-year follow-up. Serum levels of ADMA at the start of follow-up were compared between these 36 cases and 36 controls which matched to cases in terms of gender, age, history of hypertension, and myocardial infarction.@*RESULTS@#Based on the crude model, subjects in the 2 highest ADMA quartiles showed significantly higher risk of developing RCE than those in the lowest ADMA quartile [odds ratio (OR) 4.09, 95% confidence interval (CI) 1.01 to 16.58; OR 6.76, 95% CI 1.57 to 29.07]. This association was also observed in the case-mix model (OR 5.51, 95% CI 1.23 to 24.61; OR 7.83, 95% CI 1.68 to 36.41) and multivariable model (OR 6.64, 95% CI 1.40 to 31.49: OR 13.14, 95% CI 2.28 to 75.71) after adjusting for confounders. The multivariable model which combined ADMA and high-sensitivity C-reactive protein (hsCRP) showed better predictive power with areas under the receiver operator characteristic curves (0.779) than the model of either ADMA (0.694) or hsCRP (0.636).@*CONCLUSION@#Serum ADMA level may be a potential biomarker of "toxin syndrome" in CHD which shows favorable prognostic value in predicting 1-year RCE in patients with stable CHD. [The registration number is ChiCTR-PRNRC-07000012].

Establishment of β-aminopropionitrile-induced aortic dissection model in C57Bl/6J mice / 中华心血管病杂志

Objective@#To establish the mouse aorta dissection (AD) model through drinking water containing β-aminopropionitrile (BAPN).@*Methods@#Forty 3-week-old C57B1/6J male mice were divided into four groups according to randomized block design: control, 0.2, 0.4 and 0.8 g·kg-1·d-1 BAPN groups (dissolving respective dose of BAPN in the drinking water, n=10 each group). Arterial systolic blood pressure and heart rate were measured weekly in conscious, restrained mice using a noninvasive computerized tail-cuff system. Mice those died of rupture of aortic dissecting aneurysm during the study were autopsied and the aorta was examined. After 4 weeks, survived mice were sacrificed by an overdose of sodium pentobarbital and the whole aorta was harvested and analyzed.@*Results@#The incidence of AD and the mortality of ruptured AD was 0 and 0 in control group, 30% (3/10) and 20% (2/10) in 0.2 g·kg-1·d-1 BAPN group, 50% (5/10) and 40% (4/10) in 0.4 g·kg-1·d-1 BAPN group, 90% (9/10) and 70% (7/10) in 0.8 g·kg-1·d-1 BAPN group (both P<0.05 vs. control group). The incidence of AD and the mortality of ruptured AD increased in proportion to BAPN concentration increase. In 0.8 g·kg-1·d-1 BAPN group, 7 mice died of dissecting aneurysm rupture during the experiment, among which 5 dissecting aneurysms were mainly located in the thoracic aorta and 2 dissecting aneurysms in abdominal aorta. The diameters of thoracic aorta and abdominal aorta were (1.38±0.19) and (1.23±0.13) mm in control group, (2.43±1.56) and (1.30±0.26) mm in 0.2 g·kg-1·d-1 BAPN group, (2.45±1.28) and (1.30±0.31) mm in 0.4 g·kg-1·d-1 BAPN group, (2.87±0.57) and (1.95±0.81) mm in 0.8 g·kg-1·d-1 BAPN group (both P<0.05 vs. control group). The diameters of thoracic aorta and abdominal aorta in mice also increased in proportion with BAPN concentration increase. Furthermore, blood-filled false lumen formation and elastic fibers fragmentation were evidenced in hematoxylin-eosin stained and Vitoria blue-Sirius red stained aortic cross-sections of mice in the 0.8 g·kg-1·d-1 BAPN group.@*Conclusion@#BAPN treatment induced aortic dissection model in C57Bl/6J mice can serve as a useful wild-type mouse model for the mechanism and pharmaceutical studies of AD.

A Preliminary Study of the Therapeutic Role of Human Early Fetal Aorta-derived Endothelial Progenitor Cells in Inhibiting Carotid Artery Neointimal Hyperplasia / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Endothelial cell damage is an important pathophysiological step of restenosis after angioplasty and stenting. Cell transplantation has great therapeutic potential for endothelial recovery. We investigated the effect of transplanting endothelial progenitor cells (EPCs) derived from human early fetal aortas in rat injured arteries.</p><p><b>METHODS</b>The carotid arterial endothelium of Sprague-Dawley rats was damaged by dilatation with a 1.5 F balloon catheter, and then EPCs derived from human early fetal aortas (<14 weeks) were injected into the lumen of the injured artery in transplanted rats, with an equal volume of normal saline injected into control rats. Rats were sacrificed at 2 and 4 weeks after treatment and transplanted cells were identified by immunohistochemical staining with anti-human CD31 and anti-human mitochondria antibodies. Arterial cross-sections were analyzed by pathology, immunohistochemistry, and morphometry.</p><p><b>RESULTS</b>Green fluorescence-labeled EPCs could be seen in the endovascular surface of balloon-injured vessels after transplantation. The intimal area and intimal/medial area ratio were significantly smaller in the transplanted group than in the control (P < 0.05) and the residual lumen area was larger (P < 0.05). After EPC transplantation, a complete vascular endothelial layer was formed, which was positive for human von Willebrand factor after immunohistochemical staining, and immunohistochemical staining revealed many CD31- and mitochondria-positive cells in the re-endothelialized endothelium with EPC transplantation but not control treatment.</p><p><b>CONCLUSION</b>EPCs derived from human early fetal aorta were successfully transplanted into injured vessels and might inhibit neointimal hyperplasia after vascular injury.</p>

Ischemia preconditioning attenuated myocardial ischemia via upregulating the expression of adiponectin in rat / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate whether adiponectin plays a role in the protection of myocardium in the rat myocardial ischemia preconditioning (IPC) model.</p><p><b>METHOD</b>Infarct size was measured by Masson's Trichrome staining, the expression of protein and mRNA of adiponectin at 0, 6, 12 and 24 h after IPC was examined by immunohistochemistry and quantitative real time RT-PCR, plasma levels of adiponectin at above mentioned four time points after IPC were detected by ELISA in IPC and MI rats.</p><p><b>RESULT</b>Infarct size was smaller in IPC than in MI rats (20% ± 2% vs. 31% ± 3%, P < 0.05). The expression of adiponectin mRNA at 6 h and 12 h after IPC was 2.2 and 2.1 times higher than in Sham rats at respective time points (P < 0.05). Immunohistochemistry staining evidenced increased adiponectin expression in the ischemic area and weak expression of adiponectin in non-ischemic area (P < 0.05). Compared to the sham group, the plasma level of adiponectin increased significantly at 0, 6 and 12 h after IPC (0 h: 7.40 ± 0.47 vs. 10.90 ± 1.74; 6 h: 8.18 ± 1.41 vs. 10.98 ± 1.74; 12 h: 6.97 ± 1.02 vs. 9.31 ± 0.96, P < 0.05).</p><p><b>CONCLUSION</b>IPC reduced infarction size, upregulated the myocardial expression of adiponectin at mRNA and protein levels, and increased plasma adiponectin concentration, suggesting that the adiponectin may play a critical role in the protective effect of IPC.</p>

Effects of cytochrome P450 isozymes on aristolochic acid renal cytotoxicity / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effect of cytochrome P450 isozymes on aristolochic acid induced cytotoxicity on renal proximal tubular epithelial cell (cell line HK-2).</p><p><b>METHOD</b>Human renal tubular cells (cell line HK-2), were treated with aristolochic acid (AA) alone or in combination with cytochrome P450 isozymes inhibitors, including alpha-naphthoflavone (CYP450 1A1 and 1 A2 inhibitors), ketoconazole (CYP450 3A4 inhibitor), sodium diethyldithiocarbamate (CYP450 2A6 and 2E1 inhibitors), quinidine (CYP450 2D inhibitor), alpha-lipoic acid (NADPH: P450 reductase inhibitor), sulfaphenazole (CYP450 2C inhibitor) in the presence or absence of liver microsome(S9). The inhibition of cell proliferation rate was studied by MTT assay and the lactate dehydrogenase release rate was determined with continuous monitoring method.</p><p><b>RESULT</b>AA inhibits cell proliferation and promotes the release of LDH over the range of 12.5-100 mg x L(-1), in a dose-dependent manner. Addition of S9 into the culture system reduced AA cytotoxicity, with the cell proliferation inhibition reducing and the release of LDH decreasing (AA + S9 group vs the same concentration of AA alone group, P < 0.05). In the absence of S9, ketoconazole or alpha-naphthoflavone has no obvious effect on AA cytotoxicity, however,under the conditions of adding S9, ketoconazole or alpha-naphthoflavone enhances AA cytotoxicity. Other inhibitors of CYP450 isozymes has no distinct effect on AA cytotoxicity.</p><p><b>CONCLUSION</b>The microsomal enzyme of Liver can reduce the AA cytotoxicity, and CYP450 3A, CYP450 1A may be the major cytochrome P450 isozymes which impact AA cytotoxicity.</p>

Effects of perindopril and enalapril on atherosclerosis development of apolipoprotein E knockout mice / 中华心血管病杂志

<p><b>OBJECTIVE</b>To compare the effects of perindopril and enalapril on the development of atherosclerotic lesions in ApoE knockout mice.</p><p><b>METHODS</b>ApoE knockout mice were treated with perindoprilor (1.5 mg.kg(-1).d(-1), n = 20), enalapril (7.5 mg.kg(-1).d(-1), n = 20) or saline (0.2 ml saline/d, n = 20) per gavage for 20 weeks. Blood pressure and lipids were measured at the study end. Aortic root atherosclerotic plaque was then quantified and the content of collagen and the size of lipid core in the plaque assessed. Cryostat sections were used to quantify the expressions of monocyte/macrophage-2 (MOMA-2), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and matrix metalloproteinases-9 (MMP-9) in the plaque by immunofluorescence method.</p><p><b>RESULTS</b>Blood pressure and lipid profiles were similar among different groups. Compared with control group, the plaque areas of perindopril group and enalapril group displayed significantly decrease (25.33% and 22.86%, respectively, both P < 0.01). However, no significant different were observed in the plaque size between the different ACE inhibitors groups. Perindopril group and enalapril group also significantly decreased the size of lipid core (52.98% and 38.98%, respectively, both P < 0.01) and the expression of MOMA-2 (88.38% and 52.16%, respectively, both P < 0.01), ICAM-1 (80.87% and 49.59%, respectively, both P < 0.01), VCAM-1 (77.56% and 56.44%, respectively, both P < 0.01) and MMP-9 (86.93% and 55.56%, respectively, both P < 0.01), and increased the plaque collagen content (298.36% and 168.14%, respectively, both P < 0.01) and the effects of perindopril was superior to those of enalapril (all P < 0.05).</p><p><b>CONCLUSIONS</b>ACE inhibitors significantly suppressed tissue inflammation and attenuated the development of atherosclerosis in ApoE knockout mice independent of their effects on the lipid and blood pressure. Perindopril is superior to enalapril in stabilizing the plaques and has similar effect on reducing the plaque size as that of enalapril.</p>

Comparative research of thrombosis animal model induced byendotoxin in combination with carrageenan in different animals / 中国中药杂志

<p><b>OBJECTIVE</b>To compare the development of thrombosis animal model induced by endotoxin(LPS) in combination with carrageenan (Ca) in different animals.</p><p><b>METHOD</b>Two species of rats (SD and Wistar) and three species of mice (Kunming, ICR and Balb/c mice) were employed in the study. The animals of each species were randomly divided into control group and model group (LPS/Ca treatment). The animals in the model group were pretreated with Ca ip at the doses of 25 mg x kg(-1) for rats and 150 mg x kg(-1) for mice, and then treated by LPS iv sixteen hours later, while in the control group were given normal saline (NS). Thrombosis in tails was observed at 24 h after LPS iv. Hematologic parameters were tested for all the animals from each species, and the blood concentration of TNFalpha and IL-6 at different time in SD and Wistar rats were measured.</p><p><b>RESULT</b>LPS/Ca combinatory treatment could induce thrombosis animal model in all five animal species, and the thrombus could be clearly observed on the tails. All species had the similar change in hematologic parameters characterized as the significant decrease of white blood cells and platlets. Inflammatory factors TNFalpha and IL-6 could be largely induced in blood of both SD and Wistar rats at 2 h after LPS iv, but both inflammatory factors only transitorily exist in blood at the early stage of thrombosis model formation.</p><p><b>CONCLUSION</b>LPS/Ca combinatory treatment can successfully induce thrombosis animal model in all tested animal species, and thus this model has extensive animal candidates. The secretion of a large amount of inflammatory factors plays a crucial role in the formation of thrombosis animal model.</p>