鸢尾苷元对急性心肌梗死小鼠心肌的保护作用

目的观察鸢尾苷元对小鼠急性心肌梗死模型缺血心肌的影响,并探讨其作用机制。方法开胸结扎左冠状动脉前降支建立小鼠急性心肌梗死模型,分生理盐水组、复方丹参组、溶媒组、鸢尾苷元小剂量(5g·L-1)和大剂量组(10g·L-1),每组10只。观察各组心肌梗死面积、血清心肌酶、血清过氧化物歧化酶(SOD)和丙二醛(MDA)含量,及缺血心肌血管内皮生长因子A(VEGFa)、内皮型一氧化氮合成酶(eNOS)和β-肾上腺素受体激酶1(β-ARK1) mRNA的表达。结果与生理盐水组相比,鸢尾苷元组心肌梗死面积明显缩小(P<0.01),血清心肌酶和MDA含量降低(P<0.01)。心肌VEGFa和eNOS mRNA的表达上调(P<0.01),β-ARK1 mRNA的表达下调(P<0.01),且随着剂量的增加其作用加强。结论鸢尾苷元对急性心肌梗死小鼠心肌有明显的保护作用,其作用机制与其抗氧化损伤及上调VEGFa和eNOS mRNA的表达、下调β-ARK1的表达有关。     

N-benzyl-5-phenyl-1H-pyrazole-3-carboxamide promotes vascular endothelial cell angiogenesis and migration in the absence of serum and FGF-2

Aim:

To investigate the effect of N-benzyl-5-phenyl-1H-pyrazole-3-carboxamide (BPC) on angiogenesis in human umbilical vein endothelial cells (HUVECs).

Methods:

Capillary-like tube formation on matrigel and cell migration analyses were performed in the absence of serum and fibroblast growth factor (FGF-2). Reactive oxygen species (ROS) were measured using a fluorescent probe, 2′, 7′- dichlorodihydrofluorescein (DCHF). The nitric oxide (NO) production of HUVECs was examined using a NO detection kit. Morphological observation under a phase contrast microscope, a viability assay using 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl-tetrazolium (MTT) and a lactate dehydrogenase (LDH) activity analysis by a detection kit were performed to evaluate the toxicity of BPC on HUVECs in the presence of serum and FGF-2. The level of hypoxia-inducible factor 1α (HIF-1α) and the release of vascular endothelial growth factor (VEGF) were measured by Western blot and ELISA, respectively.

Results:

In the absence of serum and FGF-2, cells treated with BPC (5-20 μmol/L) rapidly aligned with one another and formed tube-like structures within 12 h. In the presence of serum and FGF-2, cells treated with BPC for 24, 48 and 72 h had no changes in morphology, viability or LDH release compared with the control group. Cell migration in the BPC-treated group was significantly increased compared with the control group. During this process, NO production and ROS level were elevated dramatically, and the levels of HIF-1α and VEGF were increased dependent on the generation of ROS.

Conclusion:

BPC most effectively promoted angiogenesis and migration in HUVECs in the absence of FGF-2 and serum.     

C/EBP beta and C/EBP delta expression is elevated in the early phase of ethanol-induced hepatosteatosis in mice

Aim： Alcohol, which is predominantly metabolized in the liver, is a major hepatic toxicant that readily induces hepatic steatosis. The expression of CCAAT enhancer binding protein （C/EBP）, especially the C/EBP delta variety, is increased in the early phase of adipogenesis. However, the role of C/EBP delta in ethanol-induced hepatosteatosis is unclear. Methods： Male C57BL/6J mice were randomized to one of four groups： a control group, a group receiving orally administered ethanol （4 g ethanol/kg body weight） （EtOH）, a high-fat-diet （HF） group and an EtOH＋HF group. Mice were sacrificed after 5 or 10 weeks for various measurements. The in vitro effect of ethanol on the expression of C/EBP alpha, beta and delta was studied in HepG2 cells. Results： By week 5, ethanol treatment had significantly increased liver C/EBP delta and beta protein expression （by 2.3- and 1.4-fold, respectively）, which then returned to the control level by week 10. In contrast, the expression of C/EBP alpha was evident only at week 10. The in vitro study shows that C/EBP delta expression was elevated significantly at 24 h but not at 48 or 72 h. C/EBP beta expres- sion was highest at 48 h, whereas C/EBP alpha expression was highest at 72 h. We also found that a low concentration of ethanol plus oleic acid enhanced C/EBP delta expression in HepG2 cells. Conclusion： C/EBP delta expression appears to play an important role in the early phase of ethanol-induced hepatosteatosis in mice and in ethanol-treated HepG2 cells. In addition, EtOH＋HF enhances the expression of C/EBP delta in HepG2 cells. Thus, C/EBP delta might be a therapeutic target in alcoholic hepatosteatosis.     

西洛他唑对小鼠慢性缺血性脑损伤的保护作用及机制

目的：观察西洛他唑对小鼠慢性缺血性脑损伤的保护作用,探讨其与促血管生成的关系。方法：以大脑中动脉栓塞方法诱导小鼠局灶性脑缺血,缺血后1、4、7h和术后1～14d腹腔注射西洛他唑（10mg／kg）,每天一次,观察缺血后35d西洛他唑对神经症状评分、斜板角度、脑梗死体积、神经元密度和缺血侧血管内皮生长因子（VEGF）、血管内皮生长因子受体2（Flk-1）表达的作用。结果：西洛他唑能降低缺血后神经症状评分,提高斜板角度,减少脑梗死体积,增加存活神经元密度和VEGF、Flk-1表达的数目。结论：西洛他唑对小鼠慢性局灶性脑缺血具有保护作用,其作用机制可能与诱导缺血侧VEGF、Flk-1表达,促进血管生成有关。     

基于网络药理学和实验验证的丹参-红花药对治疗心肌缺血的作用机制探讨

目的 通过网络药理学和动物实验探究丹参-红花药对治疗心肌缺血的潜在作用和机制。方法 检索中药系统药理学数据库与分析平台（TCMSP）和文献手动补充确定丹参-红花的活性成分及治疗心肌缺血靶点。以“心肌缺血”及“急性心肌缺血”为关键词,在CTD、DisGeNET、GeneCards和OMIM数据库中检索疾病的潜在靶点。利用Venny 2.1.0将筛选得到的有效化学成分靶点与疾病靶点进行交集,确定丹参-红花药对治疗心肌缺血的作用靶点。将交集靶点信息上传至STRING v11.0,构建活性成分-靶点网络及蛋白质相互作用网络（PPI）。通过DAVID数据库对丹参-红花治疗心肌缺血的靶点进行基因本体（GO）功能和京都基因与基因组百科全书（KEGG）通路的富集分析。40只SD雄性大鼠,根据体质量随机分成4组,每组10只,即对照组、模型组、复方丹参滴丸（73 mg·kg^-1·d^-1）组、丹参-红花（生药量16 g·kg^-1·d^-1）组。对照组和模型组大鼠每天ig等量0.9%氯化钠溶液,给药组ig相应剂量的药物,每天1次,共7 d。于第6天,除对照组外,其余各组给药1 h后sc异丙肾上腺素（ISO,85 mg·kg^-1）,连续2 d造模。HE染色观察各组大鼠心肌组织病理变化;蛋白免疫印迹法检测各组大鼠心肌组织磷酸化哺乳动物雷帕霉素靶蛋白（p-mTOR）、磷酸化转录激活蛋白3（p-STAT3）、缺氧诱导因子1α（HIF-1α）、血管内皮生长因子A（VEGFA）、血小板衍生生长因子A（PDGFA）和碱性成纤维细胞生长因子（bFGF）蛋白表达水平。结果 网络药理学筛选得到丹参-红花药对治疗心肌缺血的活性成分91个,靶点246个。PPI网络结果显示主要靶点包括STAT3、MAPK1、JUN、RELA、MAPK3、AKT1、SRC、APP、TNF、PIK3CA、CXCL8、KNG1、IL6、VEGFA、MAPK14、HSP90AA1、MAPK8、EGFR、FOS和IL2等。主要靶点相关的通路涉及血管生成（如HIF-1信号通路和VEGF信号通路）、炎症反应（如NF-κB信号通路和TNF信号通路）和细胞凋亡（如细胞凋亡信号通路和p53信号通路）等。动物实验HE染色结果表明,对照组大鼠心肌细胞正常;模型组大鼠心肌纤维肿胀且有断裂,心肌细胞增宽,局部有明显水肿、渗出、炎性细胞浸润;复方丹参滴丸组与模型组大鼠比较,心肌纤维排列略微紊乱且较窄,病理改变程度有所减轻。丹参-红花组大鼠的心肌纤维排列整齐,细胞形态结构完整,心肌纤维肿胀轻,无毛细血管扩张,接近正常心肌形态。蛋白质免疫印迹检测结果表明,与对照组比较,模型组大鼠心肌组织中HIF-1α、VEGFA、PDGFA和bFGF的蛋白表达水平显著升高（P＜0.05、0.01）,p-mTOR和p-STAT3的蛋白表达水平显著下降（P＜0.05、0.01）。与模型组比较,丹参-红花显著上调了p-mTOR、p-STAT3、HIF-1α、VEGFA、PDGFA和bFGF的蛋白表达水平（P＜0.05、0.01）。结论 丹参-红花可能通过上调与血管生成密切相关的蛋白水平来促进急性心肌缺血模型大鼠缺血心肌组织的血管生成,从而改善其缺血性损伤。     

5-HT1A和5-HT2A/2C受体在粉防己碱增强戊巴比妥钠睡眠中的介导作用

前期研究表明粉防己碱增强戊巴比妥钠诱导的催眠作用与5-HT系统相关。本研究采用戊巴比妥钠（45 mg/kg,i.p.）诱导的小鼠翻正反射消失和恢复实验方法,对粉防己碱与不同5-HT受体在增强戊巴比妥钠诱导睡眠中的相互作用进行了探讨。结果表明粉防己碱分别与选择性5-HT1A受体拈抗剂p-MPPI（1 mg/kg,i.p.）,选择性5-HT2A/2C受体拮抗剂ketanserin（1.5 mg/kg,i.p.）合用可以显著增强戊巴比妥钠诱导的催眠作用。选择性5-HT1A受体激动剂8-OH-DPAT（0.1 mg/kg,s.c.）或5-HT2A/2C受体激动剂DOI（0.2mg/kg,i.p.）能够显著减少戊巴比妥钠诱导的小鼠睡眠时间,而粉防己碱（60 mg/kg,i.g.）可以显著拮抗这种睡眠抑制作用。此结果提示,粉防己碱增强戊巴比妥钠诱导的催眠作用可能与5-HT1A受体和5-HT2A/2C受体有关。     

巴戟天醇提取物促大鼠缺血心肌治疗性血管生成的实验研究

目的探讨巴戟天糖链(MOO)对急性心肌梗死(AMI)大鼠缺血心肌治疗性血管生成的影响及其机制。方法♂Wistar大鼠,结扎冠状动脉左前降支,成功制成AMI模型40只,随机分为MOO小、中、大剂量组、麝香保心丸组及模型组,每组8只。另取10只建立假手术组。药物治疗组分别灌胃给予巴戟天醇提物水溶性部分(0.7、1.4、2.8mg.kg-1.d-1)及麝香保心丸悬浊液(30mg.kg-1.d-1),其余两组灌胃给予等量蒸馏水。连续灌胃6wk后处死大鼠,心肌取材,应用免疫组织化学法检测大鼠缺血心肌Ⅷ因子及血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)、碱性成纤维细胞生长因子(basic fibroblast growthfactor,bFGF)蛋白表达情况;计算微血管密度(microvessecdensity,MVD),用图像分析软件测定VEGF及bFGF表达灰度值,并进行半定量分析。结果与模型组相比,MOO中、大剂量组能增加缺血心肌MVD及VEGF、bFGF灰度值(P<0.05),但作用弱于麝香保心丸组(P<0.05);MOO3个剂量组之间MVD差异均有显著性(P<0.05);MOO3个剂量组之间VEGF灰度值差异均有显著性(P<0.05);MOO中、大剂量组bFGF灰度值与小剂量组相比差异有显著性(P<0.05)。结论MOO可促进AMI后大鼠缺血心肌的血管生成,其机制可能与上调缺血心肌VEGF、bFGF蛋白的表达有关。     

Hyperinsulinaemia increases the gene expression of endothelial nitric oxide synthase and the phosphatidylinositol 3-kinase/Akt pathway in rat aorta

1. Hyperinsulinaemia has been reported to be an independent risk factor for cardiovascular diseases. Insulin stimulates both the phosphatidylinositol 3-kinase (PI3-K)/Akt and mitogen-activated protein kinase (MAPK) pathways. To investigate the direct effects of insulin on vascular tissues, we examined the gene and protein expression of insulin signalling molecules, endothelial nitric oxide synthase (eNOS) and MAPK in aortas obtained from established hyperinsulinaemic rats under deep urethane anaesthesia (1.2 g/kg, i.p.). 2. High plasma insulin levels significantly enhanced the gene and protein expression of eNOS in aortas. This was accompanied not only by increased mRNA levels of insulin receptor substrate (IRS)-1, IRS-2, PI3-K and Akt, but also by a high protein content of Akt and phospho-Akt (Ser473). 3. In contrast, MAPK mRNA levels were decreased in hyperinsulinaemic rats compared with normoinsulinaemic rats. 4. Insulin receptor mRNA levels were also lower in insulin-treated rats rather than controls. The overexpression of mRNA for vascular endothelial growth factor (VEGF) and insulin-like growth factor (IGF)-I receptor was also observed in aortas from hyperinsulinaemic rats. 5. To our knowledge, these data provide the first direct measurements of the mRNA of insulin signalling molecules and the downstream eNOS and MAPK. We conclude that hyperinsulinaemia itself can lead to the upregulation of eNOS and the PI3-K/Akt pathway in the vasculature and may also induce the overexpression of VEGF and IGF-I receptor genes.     

Differential hepatoprotective mechanisms of rutin and quercetin in CCl4-intoxicated BALB/cN mice

Aim:

To investigate the mechanisms underlying the protective effects of quercetin-rutinoside (rutin) and its aglycone quercetin against CCl₄-induced liver damage in mice.

Methods:

BALB/cN mice were intraperitoneally administered rutin (10, 50, and 150 mg/kg) or quercetin (50 mg/kg) once daily for 5 consecutive days, followed by the intraperitoneal injection of CCl₄ in olive oil (2 mL/kg, 10% v/v). The animals were sacrificed 24 h later. Blood was collected for measuring the activities of ALT and AST, and the liver was excised for assessing Cu/Zn superoxide dismutase (SOD) activity, GSH and protein concentrations and also for immunoblotting. Portions of the livers were used for histology and immunohistochemistry.

Results:

Pretreatment with rutin and, to a lesser extent, with quercetin significantly reduced the activity of plasma transaminases and improved the histological signs of acute liver damage in CCl₄-intoxicated mice. Quercetin prevented the decrease in Cu/Zn SOD activity in CCl₄-intoxicated mice more potently than rutin. However, it was less effective in the suppression of nitrotyrosine formation. Quercetin and, to a lesser extent, rutin attenuated the inflammation in the liver by down-regulating the CCl₄-induced activation of nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α) and cyclooxygenase (COX-2). The expression of inducible nitric oxide synthase (iNOS) was more potently suppressed by rutin than by quercetin. Treatment with both flavonoids significantly increased NF-E2-related factor 2 (Nrf2) and heme oxygenase (HO-1) expression in injured livers, although quercetin was less effective than rutin at an equivalent dose. Quercetin more potently suppressed the expression of transforming growth factor-β1 (TGF-β1) than rutin.

Conclusion:

Rutin exerts stronger protection against nitrosative stress and hepatocellular damage but has weaker antioxidant and anti-inflammatory activities and antifibrotic potential than quercetin, which may be attributed to the presence of a rutinoside moiety in position 3 of the C ring.     

Population pharmacokinetic analysis of axitinib in healthy volunteers

AIMS

Axitinib is a potent and selective second generation inhibitor of vascular endothelial growth factor receptors 1, 2 and 3 approved for second line treatment of advanced renal cell carcinoma. The objectives of this analysis were to assess plasma pharmacokinetics and identify covariates that may explain variability in axitinib disposition following single dose administration in healthy volunteers.

METHODS

Plasma concentration–time data from 337 healthy volunteers in 10 phase I studies were analyzed, using non-linear mixed effects modelling (nonmem) to estimate population pharmacokinetic parameters and evaluate relationships between parameters and food, formulation, demographic factors, measures of renal and hepatic function and metabolic genotypes (UGT1A1*28 and CYP2C19).

RESULTS

A two compartment structural model with first order absorption and lag time best described axitinib pharmacokinetics. Population estimates for systemic clearance (CL), central volume of distribution (V_c), absorption rate constant (k_a) and absolute bioavailability (F) were 17.0 l h⁻¹, 45.3 l, 0.523 h⁻¹ and 46.5%, respectively. With axitinib Form IV, k_a and F increased in the fasted state by 207% and 33.8%, respectively. For Form XLI (marketed formulation), F was 15% lower compared with Form IV. CL was not significantly influenced by any of the covariates studied. Body weight significantly affected V_c, but the effect was within the estimated interindividual variability for V_c.

CONCLUSIONS

The analysis established a model that adequately characterizes axitinib pharmacokinetics in healthy volunteers. V_c was found to increase with body weight. However, no change in plasma exposures is expected with change in body weight; hence no dose adjustment is warranted.