Blends of hydrophobic and swelling agents in the swelling layer in the preparation of delayed-release pellets of a hydrophilic drug with low MW: Physicochemical characterizations and in-vivo evaluations

In this study, a hydrophobic material, ethylcellulose, which was used as its aqueous suspension Surelease^®, was combined with a swelling agent as the swelling layer to prepare delayed-release pellets for Danshensu, which is a hydrophilic drug with low MW. A rupturable, delayed-release pellet consists of a drug core, a swelling layer containing a swelling agent (cross-linked sodium carboxymethyl cellulose) with a hydrophobic agent (Surelease^®), and a controlled layer composed by an insoluble, water-permeable polymeric coating (aqueous ethylcellulose dispersions) was developed in a fluidised bed. Results showed that blending Surelease^® into the swelling layer could effectively extend the release of Danshensu from the pellets, which may be attributed to the slowed swelling rate by reduction of water penetration and improvement of mechanical integrity of the swelling layer. Drug in the delayed pellets showed sustained release in beagle dogs after oral administration with comparable in-vivo exposure to the uncoated drug pellets. In conclusion, blends of hydrophobic and swelling agents in the swelling layer in double-membrane pellets could achieve a delayed drug-release profile in vitro, as well as delayed and sustained absorption in vivo for highly soluble, low-MW drug. The present study highlighted the potential use of a delayed-release system for other hydrophilic, low-MW drugs to meet the formulation requirements for chronopharmacological diseases.     

丹参素通过抑制miR-199a-5p对心肌缺血再灌注损伤大鼠的保护作用

目的评估丹参素对心肌缺血/再灌注(MI/R)损伤的保护作用及其可能机制。方法 32只大鼠随机分为假手术组、模型组组、丹参素30 mg/kg组和丹参素60 mg/kg组,丹参素组在再灌注开始后5 min内iv相应剂量丹参素,假手术组和模型组注射等量生理盐水;再灌注3 h后,向冠状动脉中注入2 mL的3%伊文思蓝染料;取大鼠动脉血和心脏,通过组织化学测定心肌梗死面积大小,通过ELISA测定血清中的肌酸激酶-同工酶(CK-MB)和心肌肌钙蛋白(c TnI)水平。通过氧糖剥夺/恢复(OGD/R)H9c2心肌细胞模型评估丹参素预处理对细胞的直接作用,使用MTT、ELISA和流式细胞术分别测定丹参素对细胞活力、乳酸脱氢酶(LDH)释放和细胞凋亡的影响,使用RT-PCR和Western blotting免疫印迹测定miR-199a-5p及其下游蛋白Akt和ERK1/2的表达。结果丹参素治疗可显著降低心肌梗死面积以及血清中CK-MB和cTnI的水平(P0.05);丹参素预处理显著改善OGD/R心肌细胞活力恢复能力,减少细胞凋亡水平,显著提高Akt和ERK1/2的m RNA和蛋白表达水平,降低miR-199a-5p的m RNA表达水平(P0.05);上调miR-199a-5p显著降低Akt和ERK1/2的m RNA和蛋白表达水平(P0.05),而下调miR-199a-5p可显著提高Akt和ERK1/2的m RNA和蛋白表达水平(P0.05)。结论丹参素可以通过抑制miR-199a-5p增加Akt和ERK1/2表达来发挥心脏保护作用。     

丹参素和肝细胞生长因子对药物性肝细胞损伤的影响

目的:观察丹参素、猪再生肝细胞生长因子(PRHGF)和猪促肝细胞生长素(PHGF)对药物性肝损伤的影响。方法:以硫代乙酰胺(TAA)复制体外培养大鼠肝细胞损伤模型,通过检测培养液中LDH选出量和四甲基偶氮唑盐(MTT)显色情况了解肝细胞的存活和增殖情况,并同时检测细胞内、外SOD含量。结果:培养介质中加入TAA后,致LDH逸出明显增加,肝细胞增生指数下降,上清液和细胞内SOD活性显著降低。TAA和丹参素或PRHGF合用,则肝细胞逸出的LDH明显减少,增生指数上升并超过正常对照组,上清液和细胞内SOD活性显著升高。结论:丹参素、PRHGF和PHGF均能阻止肝细胞TAA损伤和促进肝细胞增生的作用。     

丹参制剂中原儿茶醛及丹参素的同时定量分析

目的：对复方丹参含片及滴丸中的原儿茶醛及丹参素同时进行了定量测定。方法：采用高效液相法。结果：复方丹参含片５次测定平均回收率丹参素为１００．４７％,ＲＳＤ为１．０８％,原儿茶醛为９９．２７％,ＲＳＤ为１．２２％。在丹参滴丸中３次测定的平均回收率丹参素为１００．４０％,ＲＳＤ为０．６５％,原儿茶醛为９８．４７％,ＲＳＤ为１．７６％。结论：方法简便、快速,两峰分离良好。