Baicalin-loaded PEGylated lipid nanoparticles: characterization,pharmacokinetics, and protective effects on acute myocardial ischemia in rats

Context: Baicalin has many pharmacological activities, including protective function against myocardial ischemia by antioxidant effects and free radical scavenging activity. However, its rapid elimination half-life in plasma and poor water solubility limits its clinical efficacy.

Objective: Novel baicalin-loaded PEGylated nanostructured lipid carriers (BN-PEG-NLC) were developed to improve bioavailability of BN, to prolong retention time in vivo and to enhance its protective effect.

Methods: In this study, BN-PEG-NLC were prepared by the emulsion-evaporation and low temperature-solidification method using a mixture of glycerol monostearate and polyethylene glycol monostearate as solid lipids, and oleic acid as the liquid lipid. The physicochemical properties of NLC were characterized. The pharmacokinetic and pharmacodynamic behaviors of BN-PEG-NLC or BN-NLC were evaluated in acute MI rats.

Results and discussion: The particle size, zeta potential, and entrapment efficiency for BN-PEG-NLC were observed as 83.9?nm, ?32.1?mV, and 83.5%, respectively. The release profiles of BN from both BN-PEG-NLC and BN-NLC were fitted to the Ritger–Peppas modal, which presented burst release initially and prolonged release afterwards. Pharmacokinetics results indicated that BN-PEG-NLC exhibited a 7.2-fold increase in AUC in comparison to BN solution, while a 3-fold increase in comparison to BN-NLC. Biodistribution results revealed that BN-PEG-NLC exhibited higher heart drug concentration compared with BN-NLC as well as BN solution. In the present study, BN-PEG-NLC significantly ameliorated infarct size.

Conclusion: The results of the present study imply that PEG-NLC could be the biocompatible carriers for heart-targeted drug delivery to improve myocardial ischemia.     

双黄连气雾剂稳定性的研究

采用高压液相色谱法测定了双黄连气雾剂中绿原酸与黄芩甙的含量,应用恒温加速实验法探讨了双黄连气雾剂的化学动力学过程,预测其稳定性,实验结果与留样观察法相近,同时对双黄连在降解过程中pH的变化进行了考察。     

基于网络药理学和16SrDNA测序的当归六黄汤合煎与单煎治疗阴虚甲亢作用的差异研究

目的 探讨当归六黄汤的抗阴虚甲亢作用,阐释传统汤剂合煎和单煎的差异。方法 运用网络药理学方法,筛选当归六黄汤的主要活性成分和治疗阴虚甲亢疾病的相关靶点,并对交集靶点进行蛋白质-蛋白质相互作用（protein-protein interaction,PPI）网络分析、基因本体（gene ontology,GO）功能和京都基因与基因组百科全书（Kyoto encyclopedia of genes and genomes,KEGG）通路富集分析,构建药材-成分-靶点-通路网络;进一步进行实验验证,构建阴虚甲亢大鼠模型,评价当归六黄汤合煎和单煎对阴虚甲亢大鼠体质量、粪便含水率及相关血清学指标的影响;利用16S rDNA测序技术,揭示合煎和单煎对大鼠肠道微生物群落多样性的影响。结果 筛选获得当归六黄汤方中102个活性成分,检索出与阴虚甲亢有关靶点116个。富集分析获得871条GO条目和158条KEGG相关条目（P<0.05）,其中生物过程（biological process,BP）675条、细胞组分（cellular component,CC）77条、分子功能（molecular fu...     

家兔血清中黄芩苷的薄层扫描法测定及药动学参数

采用薄层扫描法测定家兔血清中的黄芩甙及在兔体内的药物动力学参数。结果显示血清药物浓度在0．5～25μg／ml范围内线性关系良好，体内药物动力学呈开放性二室模型。并通过回收率试验确定了方法的准确性。     

葛根芩连汤不同配伍对黄芩苷、小檗碱含量的影响

目的研究葛根芩连汤在不同配伍的情况下黄芩苷、小檗碱含量的变化。方法采用反相高效液相法,选用PhenomenexC18柱(4.6mm×250mm),流动相为甲醇磷酸盐缓冲液(pH3),检测波长分别为280nm(黄芩苷)、346nm(小檗碱)。结果不同配伍对葛根芩连汤中黄芩苷、小檗碱含量影响显著。结论黄芩苷与小檗碱在煎煮后形成沉淀,从而使葛根芩连汤中的黄芩苷和小檗碱的含量大大降低。     

黄芩愈伤组织培养及黄芩苷合成调控的研究

目的研究黄芩愈伤组织培养和黄芩苷合成调控的规律。方法采用植物细胞培养技术诱导愈伤组织;HPLC法测定黄芩苷的量。结果黄芩愈伤组织生长和黄芩苷积累的优势培养条件为在基本培养基MS中氮源浓度为60mmol/L(NH4 ∶NO3-为1∶1),KH2PO4浓度0.5~1.5mmol/L,附加80g/L蔗糖,0.3mg/LIAA,2mg/L6-BA和200mg/L蛋白胨,温度(25±1)℃,暗培养。培养40d后收获愈伤组织,生物量达28.7g/L,黄芩苷为167.4mg/g,明显高于野生黄芩的最高量。结论黄芩愈伤组织的生长和黄芩苷的积累并不同步,而是先生长后合成。蔗糖对黄芩苷的合成具有明显的调节作用,在蔗糖质量浓度小于3%时,能有效促进愈伤组织的生长,但对黄芩苷的合成没有刺激作用;当蔗糖质量浓度在3%~8%时,愈伤组织表现出明显的生长和次生代谢功能,黄芩愈伤组织的生长及黄芩苷合成明显增加;当蔗糖质量浓度在8%时,两者均达到最大值。     

黄芩苷胶囊的人体生物等效性研究

目的:建立人血浆中黄芩苷浓度的高效液相-紫外(HPLC-UV)测定方法,测定志愿者口服黄芩苷胶囊后的血药浓度,估算其药动学参数并对供试制剂与参比制剂的生物等效性进行评价。方法:18名健康志愿者随机单剂量交叉口服黄芩苷试验胶囊和参比片750mg,血浆样品采用固相萃取法处理后,进行HPLC-UV测定。结果:受试及参比制剂中药物主要药动学参数如下:cmax分别为(91±s33)μg·L-1和(86±29)μg·L-1,tmax分别为(7.4±1.3)h和(7.4±1.0)h,AUC0~24分别为(586±233)μg·h·L-1和(579±173)μg·h·L-1,AUC0~∞分别为(616±249)μg·h·L-1和(613±180)μg·h·L-1。黄芩苷试验胶囊的相对生物利用度为(101±18)%。结论:本方法操作简单,专属性强,灵敏度高,准确性好。试验胶囊与参比片生物等效。     

高效液相色谱法测定清肺抑火片中黄芩苷的含量

目的:探讨清肺抑火片的含量测定方法.方法:采用高效液相色谱法(HPLC法)测定清肺抑火片黄芩中黄芩苷的含量.色谱柱为Elite 0DS C18柱(250 mm×4.0 mm,5μm),流动相为甲醇-水-磷酸(45:55:0.2),流速为1 mL/min,检测波长为315 nm.结果:回归方程为Y=85.915 4 2 701.674 3X,r=0.999 3,平均回收率为97.93%,RSD为1.76%(n=6).结论:HPLC法简便、快速、可靠,可用于清肺抑火片的质量控制.     

复方双黄连分散片的质量标准研究

目的建立复方双黄连分散片（金银花、黄芩、连翘、蒲公英等）的质量标准。方法采用TLC法对蒲公英、黄芩苷和绿原酸进行鉴别。用HPLC法测定黄芩苷的含量。结果TLC鉴别方法专属性强。黄芩苷在1．6μg～4．0μg范围内呈良好的线性关系，r=0．9998，加样回收率为99．69％，RSD为0．4％。含量限度黄芩苷为不少于80mg／片。本方法操作简单，结果准确，灵敏度高，重复性好。结论本质量标准可有效地控制复方双黄连分散片的质量。     

复方逍遥合剂中黄芩苷的薄层扫描测定

建立了薄层扫描法测定复方逍遥合剂中黄芩苷含量,并采用TLC法对黄柏、白芍、柴胡、贝母等成分进行鉴别.黄芩苷点样量在0.15～0.75μg范围内线性关系良好(r=0.9987),平均回收率99.2%(RSD 1.5%).