HPLC同时测定栀子金花丸中4种成分的含量

[目的]采用HPLC建立同时测定栀子金花丸中黄芩苷、汉黄芩苷、黄芩素、汉黄芩素这4种成分含量的分析方法。[方法]色谱柱为Agilent Zorbax SB-C18(4.6 mm×250 mm,5μm);流动相为乙腈-浓度0.1%磷酸溶液,梯度洗脱,检测波长为278 nm。[结果]黄芩苷、汉黄芩苷、黄芩素、汉黄芩素4种成分的线性范围分别为0.418~4.18μg/ml(R=0.999 8),0.2~2.0μg/ml(R=0.999 8),0.233~2.330μg/ml(R=0.999 9),0.215~2.150μg/ml(R=0.999 9);平均回收率分别是98.40%(RSD=0.45%)、98..66%(RSD=1.41%)、98.88%(RSD=1.48%)和98.97%(RSD=1.45%)。[结论]该方法快速、简便,且具有良好的重复性和回收率,可作为栀子金花丸中这4种成分的含量控制方法。     

Preparation and evaluation of self-microemulsifying drug delivery system of baicalein

The main object of this work is to prepare self-microemulsifying drug delivery system (SMEDDS) for oral bioavailability enhancement of a poorly water-soluble drug, baicalein. SMEDDS is the mixture of surfactants, cosurfactants, and oils, which are emulsified in aqueous media under conditions of gentle agitation or gastrointestinal motility. Solubility of baicalein was determined in various vehicles. Pseudo-ternary phase diagrams were constructed to identify the efficient self-emulsification region and droplet size distributions of the resultant microemulsions were determined using a particle size analyzer. Optimized SMEDDS formulations for baicalein were Cremophor RH40 (53.57%) as surfactant, Transcutol P (21.43%) as cosurfactant, and Caprylic capric triglyceride (ODO, 25%) as oil. The drug release rate of SMEDDS was significantly higher than that of the baicalein suspension. Comparison of the pharmacokinetics between baicalein-loaded SMEDDS and baicalein suspension was also performed in rats. The plasma concentrations of baicalein and baicalin, its mainly conjugated metabolite, were determined by HPLC method. The in vivo results showed that the absorption of baicalein from SMEDDS resulted in about 200.7% increase in relative bioavailability compared with that of the baicalein suspension. Our studies illustrated the potential use of SMEDDS for the delivery of hydrophobic compounds, such as baicalein by the oral route.     

Pharmacokinetic study of baicalein after oral administration in monkeys

Baicalein, a flavonoid originally isolated from the root of Scutellaria baicalensis Georgi, has numerous pharmacological activities. Up to now, several studies regarding the pharmacokinetic profiles of baicalein have been described, while there is no such study reported in monkey, the species which is more similar to human. The purpose of this study was to investigate the pharmacokinetic profiles of baicalein after oral administration in monkeys. After orally administrating three doses of baicalein in monkeys, multi-peaks of the plasma concentration-time curves were observed and the non-linear pharmacokinetics for baicalein and its metabolite baicalin were found at doses of 50-500mg/kg. In order to calculate the absolute bioavailability, the intravenous pharmacokinetic study was also carried out after intravenous administration of 10mg/kg baicalein. The absolute bioavailability of baicalein in different doses was ranged from 13.1% to 23.0%. In this study, baicalein and baicalin were determined by LC-MS method. The chromatographic separation was performed on Agilent Poroshell 120 SB-C18 column (2.7μm, 2.1×50mm). Baicalein and baicalin were detected by single quadrupole mass spectrometer equipment with electrospray ionization interface with the selected ion monitoring mode. The assay was linear for both baicalein and baicalin with the correlation coefficients>0.99. The intra- and inter-day precisions for baicalein and baicalin were all less than 15% by relative standard deviation. The analytes were stable during samples storage and handling, and no matrix effects were observed. The method we developed in this study was sensitive, precise, stable and producible.     

黄芩素对感染鼠伤寒沙门氏菌小鼠的影响

试验研究黄芩素对感染鼠伤寒沙门氏菌(STM)小鼠的影响。将80只小鼠分为空白组、STM组、黄芩素+STM组和黄芩素组。结果显示:STM使感染小鼠的存活率明显下降,小鼠血清中炎性因子水平明显增高,脏器指数降低,肝脏和脾脏组织呈现明显的病理改变。黄芩素可使感染STM小鼠的存活率明显升高,小鼠血清中炎性因子水平降低,脏器指数升高,肝脏和脾脏的病理变化明显改善。研究表明,黄芩素对STM感染的小鼠有治疗作用。     

In vitro metabolism in Sprague-Dawley rat liver microsomes of forsythoside A in different compositions of Shuang-Huang-Lian

Shuang–Huang–Lian (SHL), a traditional Chinese formula containing Lonicerae japonicae flos (LJF), Scutellariae radix (SR) and Forsythiae fructus (FF), is commonly used to treat acute upper respiratory tract infection, acute bronchitis and light pneumonia. Forsythoside A is one of the main active ingredients in Forsythiae fructus, a key herb in SHL. In the present study, effects of different compositions in SHL on the in vitro metabolism in Sprague–Dawley rat liver microsomes of forsythoside A were investigated. The observations from Sprague–Dawley rat liver microsomes in the presence of β-NADPH or UDPGA that forsythoside A may be the substrates of CYP3A4, CYP2C9, CYP1A2, UGT1A6, UGT1A3, UGT1A1 and UGT1A9; Chlorogenic acid may be the substrates of CYP3A4, CYP2C9, CYP1A2, CYP2C19, UGT1A6, UGT1A3 and UGT1A1; Baicalin may be the substrates of CYP3A4, CYP2C19, CYP1A2, UGT1A9, UGT1A1 and UGT1A3; Baicalein may be the substrates of CYP3A4, CYP2E1 and UGT1A6. It was also found that the residue of forsythoside A in SHL, FF + LJF and FF + SR was greatly increased compared with that in FF in Sprague–Dawley rat liver microsomes in the presence of β-NADPH or UDPGA, which indicated that the metabolism of forsythoside A in SHL may be influenced by chlorogenic acid in LJF acting on the CYP3A4, CYP2C9, CYP1A2, UGT1A6, UGT1A3 and UGT1A1; baicalin in SR acting on the CYP3A4, CYP1A2, UGT1A9, UGT1A1 and UGT1A3; baicalein acting on the CYP3A4 and UGT1A6 respectively.     

Baicalein induces autophagy in breast cancer cells

AIM:To investigate the autophagy of breast cancer cells induced by baicalein and to explore its mechanism.METHODS:The effects of baicalein on the viability of MCF-7 cells and 4T1 cells were investigated by MTT assay,and the dosage of the drug was determined.The expression levels of microtubule-associated protein 1 light chain 3-Ⅱ(LC3-Ⅱ) and LC3-I in the MCF-7 cells and 4T1 cells treated with baicalein at doses of 25,50 and 100 μmol/L,or combined with autophagy inhibitor 3-methyladenine (3-MA) were determined by Western blot.In order to confirm the role of baicalein in autophagy,the effect of 3-MA on the apoptosis of both MCF-7 cells and 4T1 cells induced by baicalein was analyzed by flow cytometry.The protein levels of p-mTOR,mTOR,p-AKT and AKT were examined by Western blot and the role of AKT-mTOR pathway in the induction of autophagy in breast cancer induced by baicalein was determined by the combination of activators.RESULTS:Baicalein at 50 μmol/L and above doses significantly inhibited the viability of breast cancer cells in a dose-and time-dependent manner.The expression of LC3-Ⅱ/LC3-I in both MCF-7 cells and 4T1 cells was significantly enhanced after the action of baicalein,and the ratio of LC3-Ⅱ/LC3-I was significantly decreased after 3-MA addition.The results of flow cytometry showed that,compared with baicalein group,the combination of baicalein and 3-MA promoted the levels of necrosis and apoptosis.Moreover,the protein levels of p-mTOR and p-AKT were significantly decreased and were rescued by EGF,while their total protein levels were not changed.CONCLUSION:Baicalein induces autophagy through AKT-mTOR pathway both in MCF-7 cells and 4T1 cells.     

Baicalein inhibits proliferation and migration of gastric cancer MGC-803 cells

AIM: To investigate the effects of baicalein (BAI) on the proliferation and migration of gastric cancer MGC-803 cells and the mechanisms. METHODS: After MGC-803 cells were treated with BAI at different concentrations, the viability of the MGC-803 cells was tested by MTT assay. The cell colony formation ability were detected by plate colony formation assay. Wound-healing and Transwell cell migration assays were used to test the migration ability of the MGC-803 cells. The concentration of 12-hydroxyeicosatetraenoic acid (12-HETE) was measured by ELISA. The protein levels of platelet type 12-lipoxygenase (p12-LOX), vascular endothelial growth factor (VEGF), p-ezrin and epithelial-mesenchymal transition (EMT) markers in MGC-803 cells were determined by Western blot. RESULTS: BAI significantly inhibited the proliferation, plate colony formation and migration abilities of the MGC-803 cells (P<0.05 or P<0.01), down-regulated the concentration of p12-LOX metabolite 12-HETE significantly (P<0.05 or P<0.01), decreased the protein levels of p12-LOX, VEGF, p-ezrin, vimentin and Snail (P<0.05 or P<0.01), and increased the protein expression of E-cadherin (P<0.01). CONCLUSION: BAI suppresses the proliferation and migration abilities of gastric cancer MGC-803 cells effectively. These effects of BAI may be related to regulating the protein levels of p12-LOX, VEGF, p-ezrin and EMT-related proteins.     

纤维素酶辅助提取生黄芩饮片中黄酮苷元的工艺研究

[目的]探讨生黄芩饮片黄酮类化合物的纤维素酶辅助提取优化工艺条件。[方法]采用系列单因素和正交试验设计,通过高效液相分析以黄酮苷转化成的苷元含量为考核指标,对影响辅助提取的因素进行了研究,并与传统水煎煮法比较。[结果]生黄芩黄酮苷元的最佳纤维素酶辅助提取工艺为液固比10：1,酶浓度25U／g（药材）,pH值5．O,温度50℃,提取时间7h。最佳提取条件下,黄酮苷元黄芩素和汉黄芩素的提取率分别为175．04、28．84μmol/g（药材）,分别为传统水煎煮法的6．7倍和4．8倍。[结论]纤维素酶辅助提取法提取黄芩素和汉黄芩素等转化率高,易于实现规模化生产。     

黄芩素的制备及抗糖尿病研究概况

黄芩是一种中国传统草药,国内外学者对中药黄芩的化学成分、药理作用和作用机制等方面进行了深入的研究。黄芩素（baica—lein）是黄芩苷（baicalin）的苷元,是黄芩的主要活性成分之一,是发挥药理活性的基础：现就近几年来国内外有关黄苓素的提取、纯化、含量测定和生物活性的研究成果进行综述,为全面开发利用黄芩提供参考,     

大叶海藻化学成分研究

[目的]研究分析大叶海藻的化学成分。[方法]采用MCI柱层析和半制备液相等方法从大叶海藻提取液中分离得到7个化合物,利用核磁共振(NMR)、质谱(MS)等波谱方法对其结构进行鉴定。[结果]经鉴定可知7个化合物分别为bis(2-methylpropyl)ester(1)、2-cyclohexene-1-acetic acid(2)、calycosin(3)、baicalein(4)、wogonin(5)、24-hydroperoxy-24-vinyl-cholesterol(6)和fucosterol(7)。[结论]化合物4和化合物6为首次从该植物中分到。