根皮素乳膏中根皮素的HPLC法测定

建立了高效液相色谱法测定根皮素乳膏中的根皮素.采用C18色谱柱,以甲醇-0.1%乙酸(45∶55)为流动相,检测波长286 nm.根皮素在0.02～0.20 mg/ml浓度范围内线性关系良好.回收率约99%,RSD为1.23%.     

HPLC法研究根皮素的稳定性

目的研究根皮素在不同条件下的稳定性。方法采用经典恒温法考察根皮素在不同pH值水溶液中的稳定性以及抗氧剂、强酸、强碱、强光、强氧化和高温条件下对其稳定性的影响,并研究根皮素在常温条件下,在不同溶剂和pH值缓冲液中的最大溶解度,用反相高效液相色谱法测定其含量。结果根皮素在碱性、中性和强氧化性条件下不稳定,在酸性环境、强光、高温条件下稳定。不同的抗氧化剂对其稳定性具有一定的保护作用。结论根皮素在酸性环境下比较稳定,在溶液0.1 mol·L~(-1)HCl,pH值3.0,pH值4.0,水,pH值5.0,pH值6.0,30mL·L~(-1) H_2O_2,pH值7.0缓冲液中稳定性依次降低,对于根皮素及其相关产品的研发具有重要意义,在实际应用中应加以考虑。     

原花青素对狗离体冠状血管的影响在药理学范畴的研究

目的:研究原花青素在狗冠状动脉上舒张特征和机制。方法:制备狗冠状动脉血管环,固定于盛有K-H液的恒温肌槽内,并观察等长时血管张力的变化。结果:原花青素使KCl及无钙中CaCl2量效曲线明显右移,使肌条敏感性和最大收缩反应明显降低。原花青素可使KCl预收缩冠状动脉血管环产生明显的舒张作用,Nω-L-硝基精氨酸、甲烯兰及去内皮细胞组,可部分阻断17β-雌二醇的舒张作用。结论:原花青素具有内皮依赖性和非内皮依赖性的舒血管效应,前者的作用机制与NO和NO-cGMP途径相关,而后者可能是由于原花青素对血管的直接作用引起,即抑制电压依赖性的钙通道。     

复方根皮素乳膏中根皮素、藁本内酯体外透皮吸收研究

摘 要 目的：测定复方根皮素乳膏中根皮素、藁本内酯的离体大鼠透皮吸收率。方法: 以Franz智能透皮实验仪进行体外透皮吸收试验,取不同时间点接收液,以HPLC法测定根皮素、藁本内酯含量,计算累计释放量和累计透过量,进行透皮吸收行为评价。结果: 根皮素、藁本内酯分别在0.044 2~4.42 μg·mL^-1(r=0.999 9)和0.048 7~4.87 μg·mL^-1(r=0.999 9)范围内线性良好,平均回收率分别为99.85%、99.92%,RSD分别为0.67%、0.66%(n=9),根皮素、藁本内酯透过离体大鼠皮肤的皮肤渗透行为符合Higuchi方程,r值均大于0.9,即累积渗透量Qn与时间t呈良好线性关系。结论:复方根皮素乳膏具有良好的透皮性能。     

钙通道阻滞剂的血管内皮保护作用

随着对钙通道阻滞剂的研究,逐渐发现其对血管内皮有一定的保护作用,且并不依赖于其抗高血压和抗缺血的作用。主要机制有：阻止或恢复受损血管内皮的舒张功能;影响皮细胞和平滑肌细胞间的相互作用;     

根皮素对人胃癌细胞系SGC-7901的影响及作用机制

目的 探讨根皮素对人胃癌细胞系SGC-7901的影响及其作用机制。方法 培养人胃癌细胞系SGC-7901,分别采用0.3%DMSO(DMSO组)、顺铂2.5 mg/L(DDP组)、辣椒素受体1(VR1)拮抗剂辣椒平(Cap) 0.01 mmol/L(Cap组)以及根皮素40、80、160μg/mL处理细胞,采用Cap 0.01 mmol/L预处理1 h后加根皮素160μg/mL(Cap+根皮素组)处理细胞,同时设置阴性对照组不做任何处理。MTT法检测细胞活性,流式细胞术检测细胞凋亡,通过JC-1荧光染色评估线粒体膜电位(MMP),Western blot法检测凋亡相关蛋白表达。结果 与DMSO组和阴性对照组相比,根皮素40、80、160μg/mL处理12、24、48 h后,细胞存活率降低,且呈剂量-时间依赖性(P<0.05);与DDP组比较,根皮素80、160μg/mL处理12、24、48 h后,细胞存活率降低(P<0.05);Cap+根皮素组细胞存活率较根皮素160μg/mL组增加(P<0.05)。与DMSO组和阴性对照组比较,根皮素40、80、160μg/mL处理...     

根皮素在比格犬体内的药物动力学研究

摘 要 目的：建立LC-MS/MS法测定根皮素在比格犬血浆中的浓度的方法,并将该方法应用于研究比格犬口服根皮素后的药动学行为。方法: 以白藜芦醇为内标,血浆样品经乙酸乙酯萃取,富集生物样品中的根皮素,进行LC-MS/MS检测。色谱柱：Agilent EC C18 column (100 mm ×4.6 mm, 3.5 μm),柱温：30 ℃,流动相：乙腈-水（95:5）,流速：0.5 ml·min^-1,采用电喷雾电离源（ESI）,负离子多反应监测（MRM）扫描分析,根皮素和内标白藜芦醇的离子选择通道分别为m/z 273.0→m/z 166.9,m/z 227.0→m/z 184.9;比格犬单剂量口服根皮素胶囊30 mg·kg^-1,60 mg·kg^-1,120 mg·kg^-1。于不同时间点取血测定血浆中药物的含量并利用DAS2.0软件计算其药动学参数。结果: 根皮素在50.0～125 000.0 ng·ml^-1范围内呈线性关系,平均回收率均大于93.15%,日内与日间精密度（RSD）均小于6.1%。比格犬口服30,60,120 mg·kg^-1的根皮素后,tmax分别为(180.0±69.28) min、240 min、240 min,Cmax分别为 (1 025.1 ±189.2) ng·ml^-1、(3 075.9 ±242.3) ng·ml^-1、(5 712.3±600.8) ng·ml^-1。给药剂量和AUC及Cmax成正相关。结论:该法快速、精确、简便,可用于比格犬血浆中根皮素的测定及药动学研究。随着给药剂量的增加,AUC和Cmax明显增加,t1/2没有明显差异,CL/F减小。     

根皮素的抗炎和免疫抑制作用 (英文)

探讨根皮素（phloretin）在体外对小鼠T淋巴细胞增殖、活化、周期和巨噬细胞NO释放、吞噬功能的影响。CFDA-SE标记技术结合流式细胞术检测根皮素对T淋巴细胞增殖的影响。荧光抗体染色结合流式细胞术分析根皮素对T淋巴细胞在Con A的刺激下CD69和CD25的表达水平的影响。碘化丙啶（PI）染色检测细胞周期的分布情况。Griess试剂盒和荧光微球分别用以检测巨噬细胞NO释放和吞噬功能。结果显示,根皮素（40、60和80 μmol·L^-1）明显抑制T淋巴细胞增殖,增殖指数（PI）从1.41 ± 0.13分别下降到1.34 ± 0.16、1.19 ± 0.12和1.07 ± 0.06。根皮素可明显抑制CD69和CD25的表达（P < 0.01）。细胞周期分析显示,根皮素可将细胞抑制在G₀/G₁期。巨噬细胞在LPS和IFN-γ的刺激下的NO释放量为（26.72 ±3.57）μmol·L^-1,而在根皮素作用下NO释放量明显下降（P < 0.01）。巨噬细胞吞噬率在根皮素作用下也明显下降（P < 0.01）。以上结果表明,根皮素有望发展成为一种新的免疫抑制药物。
     

白藜芦醇对离体犬冠状动脉血管环的影响

目的：研究白藜芦醇和17β-雌二醇对狗冠状动脉舒张特征的影响及其机制。方法：制备狗冠状动脉血管环，固定于盛有K-H液的恒温肌槽内，并观察等长时血管张力的变化。结果：白藜芦醇和17β-雌二醇使KCI及无钙K-H液中CaCl2量效曲线明显右移，使肌条敏感性和最大收缩反应明显降低。Nω-L-硝基精氨酸、甲烯兰、正矾酸钠及去细胞内皮，可部分阻断白藜芦醇和17β-雌二醇的舒张血管作用。格列本脲组对白藜芦醇和17β-雌二醇的舒张作用没有影响。结论：白藜芦醇和17β-雌二醇舒张血管都具有内皮依赖性，与KATP仰通道无关。     

根皮苷及根皮素对小鼠的半数致死量测定

摘 要 目的:研究根皮苷及根皮素对昆明种小鼠的急性毒性作用和测定半数致死量(LD50)。方法: 通过昆明小鼠口服不同浓度的根皮苷及根皮素溶液,观察并记录根皮苷及根皮素对小鼠的毒性反应。利用SPSS(windows 100版) one way ANOVA统计学软件计算其对小鼠的半数致死量(LD50)。结果:昆明种小鼠口服根皮苷及根皮素的LD50分别为9.067、5.760 g·kg^-1,二者的95%可信区间为8.239 8～9.977 5 g·kg^-1,5.364 8～6.184 4 g·kg^-1。结论:根皮素和根皮苷口服毒性极小,其用量安全可靠。     

Hepatotoxicity and endothelial dysfunction induced by high choline diet and the protective effects of phloretin in mice

The involvement of choline and its metabolite trimethylamine-N-oxide (TMAO) in endothelial dysfunction and atherosclerosis has been repeatedly confirmed. Phloretin, a dihydrochalcone flavonoid usually present in apples, possesses a variety of biological activities including vascular nutrition. This study was designed to investigate whether phloretin could alleviate or prevent high choline-induced vascular endothelial dysfunction and liver injury in mice. Mice were provided with 3% high choline water and given phloretin orally daily for 10 weeks. The high choline-treated mice showed the significant dyslipidemia and hyperglycemia with the impaired liver and vascular endothelium (p < 0.01). Administration of phloretin at 200 and 400 mg/kg bw significantly reduced the choline-induced elevation of serum TC, TG, LDL-C, AST, ALT, ET-1 and TXA2 (p < 0.01), and markedly antagonized the choline-induced decrease of serum PGI2, HDL-C and NO levels. Furthermore, phloretin elevated hepatic SOD and GSH-Px activities and decreased hepatic MDA levels of the mice exposed to high choline water. Moreover, histopathological test with the H&E and Oil Red O staining of liver sections confirmed the high choline diet-caused liver steatosis and the hepatoprotective effect of phloretin. These findings suggest that high choline causes oxidative damage, and phloretin alleviate vascular endothelial dysfunction and liver injury.     

The estrogenic effects of apigenin,phloretin and myricetin based on uterotrophic assay in immature Wistar albino rats

Chemicals that occur in vegetal food and known as phytoestrogens, because of their structures similarity to estrogen, have benefits on chronic diseases. Despite this, when they are taken at high amounts, they can cause harmful effects on endocrine system of human and animals. In this study, it has been intended to determine the estrogenic potencies of phytoestrogens apigenin, phloretin and myricetin whose affinities for estrogen receptors in vitro. The female rats divided into 17 groups, each containing six rats. There was a negative control group and there were positive control dose groups which contains ethinyl estradiol, ethinyl estradiol + tamoxifen and genistein. The other dose groups which were tested for estrogenic activity contains apigenin, myricetin and phloretin All chemicals have been given to Wistar immature female rats with oral gavage for 3 consecutive days. By using uterotrophic analysis, uterus wet and blotted weights, vaginal opening, uterus length of female rats has been recorded at the end of the experiment. For detect of cell response, luminal epithelium height, gland number and lactoferrin intensity in luminal epithelium of uterus were evaluated. Biochemical analysises in blood were performed.     

Detrimental effects of anabolic steroids on human endothelial cells

The aim of this study is to investigate the effects in vitro induced by androgenic anabolic steroids (AAS) (testosterone, nandrolone, androstenedione, norandrostenedione, and norandrostenediol) used illicitly in sport competitions, on the proliferation ability, apoptosis and the intracellular calcium concentration ([Ca2+]i) in human umbilical vein endothelial cells (HUVECs), selected as a prototype of a biological target system whose structure and function can be affected by steroids. For this purpose, we evaluated the proliferation inhibition by cytotoxic assay expressed as the concentration of drug inducing a 50% decrease in growth (IC50). The IC50 was reached for testosterone at 100 microM, androstenedione at 375 microM, nandrolone at 9 microM, norandrostenedione at 500 microM. The IC50 value for norandrostenediol was not reached until a concentration of 6000 microM. The apoptotic effect was evaluated by flow cytometry at IC50 for each drug. We observed that testosterone induced 31% of apoptotic cells, norandrostenedione 25%, androstenedione 15% and nandrolone 18%. We have analyzed the effects of these drugs on [Ca2+]i both in the immediate and long-term continuous presence of each compound. Our data show a statistically significant increase of [Ca2+]i in the acute condition and in long-term treated cultures, suggesting that androgen steroids modulate intracellular levels of calcium independent of incubation time or compound identity. As a whole, this study demonstrates that AAS might alter endothelial homeostasis, predisposing to the early endothelial cell activation that is responsible for vascular complications observed frequently in AAS users.     

Isolation and In Vitro Culture of Vascular Endothelial Cells from Mice

In cardiovascular disorders, understanding of endothelial cell (EC) function is essential to elucidate the disease mechanism. Although the mouse model has many advantages for in vivo and in vitro research, efficient procedures for the isolation and propagation of primary mouse EC have been problematic. We describe a high yield process for isolation and in vitro culture of primary EC from mouse arteries (aorta, braches of superior mesenteric artery, and cerebral arteries from the circle of Willis). Mouse arteries were carefully dissected without damage under a light microscope, and small pieces of the vessels were transferred on/in a Matrigel matrix enriched with endothelial growth supplement. Primary cells that proliferated in Matrigel were propagated in advanced DMEM with fetal calf serum or platelet-derived serum, EC growth supplement, and heparin. To improve the purity of the cell culture, we applied shearing stress and anti-fibroblast antibody. EC were characterized by a monolayer cobble stone appearance, positive staining with acetylated low density lipoprotein labeled with 1,1''-dioctadecyl-3,3,3'',3''-tetramethyl-indocarbocyanine perchlorate, RT-PCR using primers for von-Willebrand factor, and determination of the protein level endothelial nitric oxide synthase. Our simple, efficient method would facilitate in vitro functional investigations of EC from mouse vessels.     

白花前胡提取成分对心血管作用的研究进展

目的介绍国内外中药白花前胡提取成分对心血管作用的研究进展 ,为研究和开发中草药提供参考。方法以国内外大量有代表性的文献为基础 ,进行分析、整理和归纳。结果白花前胡提取成分保护心血管作用可能通过以下机制 :a .阻滞钙内流 ;b .抑制血小板聚集作用 ;c .促钾通道开放 ;d .调节心肌细胞动作电位 ;e .抗氧自由基和脂质过氧化作用实现。结论白花前胡及其有效成分在研究和开发防治心血管疾病新药方面具有广阔前景     

钙、锌对铅致大鼠记忆障碍的保护机制探讨

目的　主要探讨饲料钙、锌干预对脑发育期低水平铅暴露致大鼠仔鼠学习记忆障碍保护作用的可能机制。方法　大鼠孕 14d至仔鼠出生 40d饮 10 0mg L含铅水 ,进食加钙 (1 2 5 % )和加锌 (10 0mg kg)配方饲料组 ,观察仔鼠生长发育情况 ,仔鼠 40d取股动脉血分析全血铅含量 ;取右半侧大脑分析脑铅含量 ;取左侧海马和小脑分析NO含量 ,右侧海马分析蛋白激酶C(PKC)活性。结果　两干预组仔鼠脑铅平均值分别为 3 0 5和 0 62 μg g ,明显低于进食普通配方饲料组 ,而加钙组血铅平均值为 0 2 9μmol L,明显低于加锌和普通配方组 ;两干预组海马和小脑一氧化氮 (NO)平均值分别为 2 7 68和 13 82 μmol g组织蛋白 ,均高于普通配方组 ,而海马细胞胞浆蛋白激酶C活性平均值分别为 0 3 3和 0 3 8pmol (min .μg组织蛋白 ) ,均低于普通配方组。结论　饲料中钙、锌干预对低水平铅暴露致大鼠学习记忆障碍的保护作用可能与降低其体内血、脑中铅蓄积水平 ,升高海马和小脑NO含量以及降低海马细胞胞浆内PKC活性有关     

白杨素对大鼠离体肾动脉的舒张作用

目的研究白杨素对大鼠离体肾动脉的舒张作用及其机制是否涉及抑制肾动脉血管平滑肌细胞L-型电压依赖性钙通道。方法利用微血管张力记录仪(DMT)观察白杨素对预收缩大鼠肾动脉血管环的肌源性反应;利用全细胞膜片钳电生理学实验方法,观察白杨素对大鼠离体肾动脉血管平滑肌细胞L-型电压依赖性钙电流的作用。结果 1白杨素浓度依赖性的舒张60 mmol/L KCl或10-5 mol/L去氧肾上腺素(PE)预收缩的大鼠肾动脉血管环,其最大舒张幅度分别为88.99%和67.47%,RC50值分别为26.25μmol/L和51.68μmol/L。2白杨素(浓度为RC50值)可抑制大鼠肾动脉血管平滑肌细胞L-型电压依赖性钙电流,使其I-V曲线非平行上移;给予0 mV单电压刺激时,白杨素(浓度为RC50值)使大鼠肾动脉血管平滑肌细胞L-型电压依赖性钙电流值降低45.43%。结论 1白杨素浓度依赖性舒张60 mmol/L KCl或10-5 mol/L PE预收缩的大鼠肾动脉血管环;2白杨素抑制大鼠肾动脉血管平滑肌细胞L-型电压依赖性钙电流,使其I-V曲线非平行上移。     

冠状动脉微血管内皮细胞功能障碍分子机制的研究进展

冠状动脉微血管疾病是多种心血管事件发生的高风险因素,因其病因较为复杂且具有一定隐蔽性,导致现阶段针对其病机机制仍较为有限。在冠状动脉微血管内皮细胞（CMEC）功能障碍的发生及发展的过程中,CMEC损伤是导致其发生的主要核心环节,CMEC的代谢能力、应激能力以及炎症等相关功能均与CMEC功能障碍疾病密切相关,同时也是其发生早期的主要临床特征。由于现阶段关于CMEC损伤的相关病理机制尚未完全明确,基于此,本研究对CMEC功能障碍的相关病理机制加以综述,以期为临床医护人员对该病发生的复杂病理机制更好理解,从而为后续相关研究的进展提供一定参考依据。     

20-羟-二十烷四烯酸在糖尿病心血管并发症中的作用

糖尿病是以高血糖为特征的代谢紊乱综合征,其心血管并发症是导致糖尿病患者致残、致死的主要原因.20-羟-二十烷四烯酸(20-hydroxyeicosatetraenoic acid,20-HETE)是近年来发现的花生四烯酸(Arachidonic acid,AA)第三条代谢通路,细胞色素P-450(Cytochrome P-450,CYP450)途径的活性代谢产物.现有研究表明其在调节肾功能和血管平滑肌紧张度中起到重要作用,但对20-HETE与糖尿病的关系研究甚少.本文对近年来国际上20-HETE与糖尿病心血管并发症的研究报道进行综述.     

金钠多 艾司洛尔减轻缺氧刺激内皮细胞分泌内皮素的作用比较

目的观察缺氧对血管内皮细胞(VEC)分泌内皮素(ET)的影响及金钠多和艾司洛尔的保护作用。方法将培养的血管内皮细胞分为4组:空白对照组、单纯缺氧组、缺氧+金钠多组、缺氧+艾司洛尔组。除空白对照组外,其他各组置于低压舱内进行缺氧暴露。用放射免疫法测定各组缺氧前和缺氧后0.5、6和24hET含量。结果①缺氧可促进VEC分泌ET增加(P<0.01)。②同单纯缺氧组比较,在缺氧后0.5、6、24h时,金钠多组的ET含量明显降低(P<0.01)。③同单纯缺氧组比较,在缺氧后0.5h艾司洛尔组的ET含量明显降低(P<0.01),但在缺氧后6h和24h时,两组ET含量差异无统计学意义(P>0.05)。④金钠多组与艾司洛尔组比较,ET浓度降低在0.5h差异无统计学意义(P>0.05),但在6h和24h金钠多组ET含量较艾司洛尔组明显降低(P<0.01)。结论缺氧可使VEC释放ET显著增加;金钠多和艾司洛尔能抑制缺氧促VEC分泌ET的作用;金钠多的保护作用更强于艾司洛尔。