HPLC法测定匹伐他汀钙中6种有关物质

目的建立了高效液相色谱梯度洗脱法测定匹伐他汀钙中有关物质的方法。方法采用C18（4.6mm×250mm,5μm）色谱柱,以醋酸盐缓冲液（取醋酸钠0.15g,冰醋酸0.5mL,加水稀释至1000mL）为流动相A,乙腈为流动相B,梯度洗脱条件：0～20min,A为56%;20～40min,A为56%→30%;40～60min,A为30%;以1.0mL.min-1的流速进行梯度洗脱;检测波长为245nm。结果匹伐他汀钙与各有关物质的分离度良好,匹伐他汀钙及杂质Ⅰ、Ⅱ、Ⅲ、Ⅴ、Ⅵ的检测限均为0.04μg.mL-1。结论所建立的方法简便、灵敏、准确,可用于匹伐他汀钙有关物质的测定。     

The effect of pitavastatin calcium on endothelial dysfunction induced by hypercholesterolemia

Objective: To investigate whether endothelial function can be improved by the treatment of pitavastatin calcium via its antioxidant properties in hypercholesteremia patients.

Methods: Forty patients with hypercholesteremia were randomized to receive pitavastatin calcium 1 or 2 mg/day for 8 weeks. Among them, four people were lost in the follow-up period. Before and after treatment, clinical and biochemical characteristics, markers of oxidative stress (plasma 8-iso-prostaglandin F_2α and serum gp91phox) were determined and concomitantly endothelium-dependent brachial artery flow-mediated dilation (FMD) was measured by ultrasound examination. Thirty healthy subjects were chosen as controls.

Results: For individuals with hypercholesteremia, total cholesterol, low-density lipoprotein cholesterol (LDL-C) and serum gp91phox were significantly increased (p < 0.001 for all) and plasma 8-iso-prostaglandinF2α (8-iso-PGF2α) was significantly higher (p < 0.05), while FMD was obviously impaired (p < 0.001). Total cholesterol, LDL-C and serum gp91phox were significantly reduced (p < 0.001 for all), plasma 8-iso-PGF2α was lower and FMD was significantly improved after pitavastatin calcium treatment compared with those before treatment in any group (p < 0.05 for both). However, there was no significant difference between the 1-mg and 2-mg pitavastatin calcium groups post-therapy.

Conclusions: Endothelial dysfunction induced by hypercholesteremia can be ameliorated by pitavastatin calcium treatment, which occurs in part through its antioxidative properties.     

CYP2C76-mediated species difference in drug metabolism: A comparison of pitavastatin metabolism between monkeys and humans

The monkey is often used to predict metabolism of drugs in humans since it generally shows a metabolic pattern similar to humans. However, metabolic profiles different from humans are occasionally seen in monkeys for some drugs including pitavastatin. Recently, we have successfully identified a monkey-specific cytochrome P450 (CYP) 2C76, which possibly accounts for a species difference between monkeys and humans because of its sequence and functional uniqueness. The present study on the role of CYP2C76 and other monkey CYP2Cs in pitavastatin metabolism, as an example, has revealed that CYP2C76 is important for the metabolism of the lactone form, indicating a major role of CYP2C76 for the difference in the metabolism of pitavastatin and possibly other drugs between monkeys and humans. The current investigation on the involvement of CYP2C76 in the metabolism of other drugs is expected to reveal further the further importance of this monkey-specific drug-metabolizing enzyme.     

Unremarkable impact of Oatp inhibition on the liver concentration of fluvastatin,lovastatin and pitavastatin in wild-type and Oatp1a/1b knockout mouse

1. Oatp inhibitors have been shown to significantly increase the plasma exposure of statins. However, understanding alterations of liver concentration is also important. While modeling has simulated liver concentration changes, availability of experimental data is limited, especially when concerning drug–drug interactions (DDI). The objective of this work was to determine blood and liver concentrations of fluvastatin, lovastatin and pitavastatin, when blocking uptake transporters.

2. In wild-type mouse, rifampin pre-treatment decreased the unbound liver-to-plasma ratio (K_p,uu) of fluvastatin by 4.2-fold to 2.2, lovastatin by 4.9-fold to 0.81 and pitavastatin by 10-fold to 0.21. Changes in K_p,uu were driven by increases in systemic exposures as liver concentrations were not greatly altered.

3. In Oatp1a/1b knockout mouse (KO), rifampin exerted no additional effect on fluvastatin and lovastatin. Contrarily, rifampin further decreased pitavastatin K_p,uu by 3.4-fold, suggesting that the KO is inadequate to completely block liver uptake of pitavastatin as there are additional rifampin-sensitive uptake mechanism(s) not captured in the KO model.

4. This work provides experimental data showing that the plasma compartment is more sensitive to Oatp modulation than the liver compartment, even for rifampin-mediated DDI. Consistent with previous simulations, inhibiting or targeting Oatps may change K_p,uu, but exhibit only a minimal effect on absolute liver concentrations.     

LC-MS测定人血浆中匹伐他汀浓度及其应用

目的建立LC-MS测定人血浆中匹伐他汀的浓度。方法采用Shim-pack C18色谱柱,流动相A为甲醇,流动相B为含0.025%氨水和0.05mmol·L^-1醋酸铵的水溶液,采用梯度洗脱方式。质谱检测方式：SIM。以瑞舒伐他汀为内标,血浆样品用乙酸乙酯提取浓缩检测,进行LC-MS分析。结果匹伐他汀在0.2～200.0ng·mL^-1内线性关系良好（r=0.9999）;平均提取回收率均为86.28%;日内日间RSD均小于12%。结论本方法快速、简捷、准确,适用于匹伐他汀的临床药动学研究和血药浓度监测。     

匹伐他汀钙的合成

2-环丙基-4-（4-氟苯基）-喹啉-3-羧酸乙酯经KBH4／ZnCl2还原、溴化、制得膦叶立德后，与（3R，5S）-6-氧代-3，5-二羟基-3，5．0-亚异丙基己酸叔丁酯进行Wittig-Homor反应、脱保护并内酯化、水解成盐制得HMG CoA还原酶抑制剂类降血脂药物匹伐他汀钙，总收率约31％。     

匹伐他汀提高心肌过氧化物酶Ⅲ、细胞外超氧化物歧化酶表达减轻心肌肥厚

目的:探讨匹伐他汀对大鼠心肌肥厚模型氧化应激水平、过氧化物酶Ⅲ(PrxⅢ)和细胞外超氧化物歧化酶(EC-SOD)表达的影响。方法:SD大鼠随机分为对照组、心肌肥厚组和匹伐他汀组。心肌肥厚组和匹伐他汀组大鼠背部皮下注射异丙肾上腺素7 d制备心肌肥厚模型,对照组注射等体积生理盐水。匹伐他汀组大鼠于注药前7 d即给予匹伐他汀灌胃共14 d。注药7 d后测定大鼠右颈总动脉收缩压(SBP)、舒张压(DBP),计算平均动脉压(MAP)。取心称量全心质量(HW)和左心室质量(LHW),计算心重指数(HW/BW,LHW/BW);分离并测量室间隔(VST)与游离室壁(LVWT)厚度;光学、电子显微镜观察心肌的形态结构;检测血清乳酸脱氢酶(LDH)活性、心肌内丙二醛(MDA)、过氧化氢(H_2O_2)含量、PrxⅢ和ECSOD的mRNA与蛋白水平表达变化。结果:光镜和电镜观察显示,心肌肥厚组和匹伐他汀组大鼠呈心肌细胞肥大表现,但匹伐他汀组形态改变轻于心肌肥厚组;与对照组相比,心肌肥厚组和匹伐他汀组大鼠MAP、HW/BW、LHW/BW、VST、LVWT、血清LDH活性、MDA和H_2O_2含量均明显增加,但匹伐他汀组却低于心肌肥厚组;心肌肥厚组和匹伐他汀组大鼠心肌组织PrxⅢ和EC-SOD的mRNA和蛋白表达量高于对照组,而匹伐他汀组大鼠PrxⅢ和EC-SOD表达量又高于心肌,肥厚组。结论:匹伐他汀能降低大鼠心肌肥厚模型氧化应激水平,改善心肌形态结构和功能的改变,这可能与抗氧化酶PrxⅢ和EC-SOD的表达增强密切相关。     

高糖诱导人THP1细胞Toll样受体4信号通路变化及匹伐他汀的拮抗作用

目的探讨高糖刺激下人单核/巨噬细胞系（Thp1）细胞表面Toll样受体4（TLR4）表达和信号通路活性变化,并探讨匹伐他汀对高糖引起该信号通路表达变化的作用及可能的机制。方法体外培养Thp1细胞,分为对照组（0mmol·L~（-1）葡萄糖）、低葡萄糖浓度组（5.5mmol·L~（-1）葡萄糖）、高葡萄糖浓度组（15、25 mmol·L~（-1）葡萄糖）、高糖（15mmol·L~（-1）葡萄糖）＋匹伐他汀组（0.01、0.1、1μmol·L~（-1）匹伐他汀）,各组细胞干预24 h后,Real-TimePCR方法检测各组细胞TLR4、MCP1、IL6基因表达水平,Western印迹法检测各组细胞TLR4、Myd88蛋白表达水平。结果随着葡萄糖浓度从5.5mmol·L~（-1）升高到25 mmol·L~（-1）,Thp1细胞TLR4、MCP1、IL6基因表达及TLR4、Myd88蛋白水平逐渐增加。Thp1细胞在高糖刺激前给予匹伐他汀预孵1 h,TLR4、MCP1、IL6基因水平及TLR4、Myd88蛋白水平随匹伐他汀浓度的增加逐渐下降。结论高糖能剌激人Thp1细胞TLR4信号通路激活,呈剂量依赖性诱导TLR4、IL6、MCP1表达升高,且高糖激活的信号通路可能为Myd88依赖途径;匹伐他汀可以拮抗高糖诱导的TLR4信号通路激活,抑制炎症反应的放大。     

Comparative long-term efficacy and tolerability of pitavastatin 4 mg and atorvastatin 20-40 mg in patients with type 2 diabetes mellitus and combined (mixed) dyslipidaemia

Aim: To compare the long‐term efficacy and safety of pitavastatin with atorvastatin in patients with type 2 diabetes and combined (mixed) dyslipidaemia. Methods: Randomised, double‐blind, active‐controlled, multinational non‐inferiority study. Patients were randomised 2 : 1 to pitavastatin 4 mg (n = 279) or atorvastatin 20 mg (n = 139) daily for 12 weeks. Patients completing the core study could continue on pitavastatin 4 mg (n = 141) or atorvastatin 20 mg (n = 64) [40 mg (n = 7) if lipid targets not reached by week 8] for a further 44 weeks (extension study). The primary efficacy variable was the change in low‐density lipoprotein cholesterol (LDL‐C). Results: Reductions in LDL‐C were not significantly different at week 12 between the pitavastatin (?41%) and atorvastatin (?43%) groups. Attainment of National Cholesterol Education Program and European Atherosclerosis Society targets for LDL‐C and non‐high‐density lipoprotein cholesterol (non‐HDL‐C) was similarly high for both treatment groups. Changes in secondary lipid variables (e.g. HDL‐C, apolipoprotein B and triglycerides) were similar between treatments. Post hoc analysis showed that adjusted mean treatment differences for pitavastatin vs. atorvastatin were within the non‐inferiority margin at weeks 16 (+0.11%; 95% confidence interval (CI), ?5.23 to 5.44) and 44 (?0.02%; 95% CI, ?5.46 to 5.41) of the extension study. Both treatments were well tolerated; atorvastatin increased fasting blood glucose from baseline (+7.2%; p < 0.05), whereas pitavastatin had no significant effect (+2.1%). Conclusions: Reductions in LDL‐C and changes in other lipids were not significantly different in patients treated with pitavastatin 4 mg or atorvastatin 20 or 40 mg. Pitavastatin may, however, have a more favourable effect on the glycaemic status.