紫草素抑制单核细胞募集及其对人鼠嵌合内异症模型的影响

目的:探讨紫草素影响子宫内膜异位症(EMs)小鼠模型RANTES募集单核细胞、抑制异位内膜生长的作用机制。方法:建立人鼠嵌合型EMs动物模型,设大(10mg/kg)、中(5mg/kg)、小(2.5mg/kg)剂量紫草素治疗组,治疗28d。另设PBS阴性对照组、达菲林阳性对照组,采用形态学方法比较紫草素对EMs小鼠模型移植人子宫蜕膜生长抑制的情况;体内趋化实验评价紫草素对RANTES募集单核细胞的影响。结果:不同剂量紫草素及达菲林均能抑制小鼠体内人子宫蜕膜的生长,与PBS组比较,差异显著(P<0.05)。其中大、中剂量组异位灶缩小最显著(分别为P=0.000和P=0.001),其次为达菲林组(P=0.003)和小剂量组(P=0.011),各组间比较差异无显著意义(P>0.05)。紫草素明显抑制rhRANTES对U937细胞的趋化作用(P<0.05)。结论:人鼠嵌合型EMs动物模型可用于EMs的研究。紫草素能抑制异位灶生长,该作用可能通过抑制趋化因子募集单核细胞至腹腔,减轻腹腔炎症而起作用。     

紫草素诱导人绒毛膜癌JEG-3细胞凋亡机制的研究

背景与目的：研究紫草素（shikonin）诱导人绒毛膜癌JEG-3细胞的凋亡作用及其机制。材料与方法：采用四甲基偶氮唑盐（MTT）法测定紫草素对JEG-3细胞生长的抑制作用;Hoechst33258荧光染色和流式细胞术（FCM）检测紫草素处理JEG-3细胞后发生凋亡的形态变化;Western blot检测凋亡相关蛋白的活化。结果：MTT分析表明,紫草素抑制JEG-3细胞增殖,并呈时间和剂量依赖性（P〈0．01）,其半数有效抑制浓度（IC50）为（6．3&#177;0．6）μmol／L;紫草素处理JEG-3细胞后,Hoechst33258染色出现典型的凋亡特征,且FCM检测出现明显的亚二倍体峰,Annexin V／P1双染出现早期凋亡细胞;Western blot检测结果显示经紫草素处理后JEG-3细胞的Caspase-3、ERK、JNK蛋白均被激活,而PARP蛋白被剪切成cleaved PARP（85KD）。结论：紫草素可能经Caspase-3途径诱导人绒毛膜癌细胞JEG-3凋亡,并且MAPK通路的活化、抑制对细胞的凋亡有一定的影响。     

紫草素的脂质体制备工艺及其质量评价研究

目的:研究紫草素脂质体的制备方法及质量评价。方法:采用薄膜超声法制备紫草素脂质体,超速离心法测其包封率;以包封率、粒径为指标,采用正交试验设计法优化处方,并对其表面特征、包封率、粒径、Zeta电位进行考察。结果:优化处方制备的脂质体平均粒径为187.73 nm,药物的平均包封率为76.9%,Zeta电位绝对值为38.94 mV,外观圆整,分散均匀。结论:制备的紫草素脂质体包封率较高,粒径小,混悬液体系稳定,为紫草素脂质体的进一步研究奠定基础。     

复方川紫方提取工艺研究

<正>复方川紫方是本院经验方,由川芎、紫草、羌活等十余味药组成,功能抗菌消炎、通络止痛、行气活血散瘀,临床以油剂外敷,用于治疗肩周炎、网球肘等,疗效较好。其采用油炸古法制作,在有效成分提取、用药安全等方面存在一定不足。为进一步提高产品质量,保证临床应用安全有效、稳定可控,我们采用正交设计对该复方的提取工艺进行考察,优选最佳提取条件,为产品的生产工艺改进提供依据。     

Synthesis and Biological Evaluation of Heterocyclic Carboxylic Acyl Shikonin Derivatives

A series of shikonin derivatives ( 1 – 13 ) that were acylated selectively by various thiophene or indol carboxylic acids at the side chain of shikonin were synthesized, and their biological activities were also evaluated as potential tubulin inhibitors. Among them, compound 3 ((R)‐1‐(5,8‐dihydroxy‐1,4‐dioxo‐1,4‐dihydronaphthalen‐2‐yl)‐4‐methylpent‐3‐enyl 3‐(1H‐indol‐3‐yl)propanoate) and compound 8 ((R)‐1‐(5,8‐dihydroxy‐1,4‐dioxo‐1,4‐dihydronaphthalen‐2‐yl)‐4‐methylpent‐3‐enyl 2‐(thiophen‐3‐yl)acetate) exhibited good antiproliferative activity of A875 (IC₅₀ = 0.005 ± 0.001 μm , 0.009  ± 0.002 μm ) and HeLa (IC₅₀ = 11.84 ± 0.64 μm , 4.62  ± 0.31 μm ) cancer cell lines in vitro, respectively. Shikonin (IC₅₀ = 0.46 ± 0.002 μm , 4.80 ± 0.48 μm ) and colchicine (IC₅₀ = 0.75 ± 0.05 μm , 17.79 ± 0.76 μm ) were used as references. Meanwhile, they also showed the most potent growth inhibitory activity against tubulin (IC₅₀ of 3.96  ± 0.13 μm and 3.05 ± 0.30 μm , respectively), which were compared with shikonin (IC₅₀ =  15.20 ± 0.25 μm ) and colchicine (IC₅₀ = 3.50 ± 0.35 μm ). Furthermore, from the results of flow cytometer, we found compound 3 can really inhibit HeLa cell proliferation and has low cell toxicity. Based on the preliminary results, compound 3 with potent inhibitory activity in tumor growth may be a potential anticancer agent.     

紫草素对IL-17诱导角质形成细胞增殖及趋化因子表达的影响

目的: 观察紫草素(shikonin)对IL-17诱导人角质形成细胞增殖及其分泌趋化因子的影响,探讨紫草素治疗银屑病的作用机制。 方法: 采用IL-17A(200 μg·L^-1)刺激体外培养的HaCaT 细胞,同时加入不同浓度紫草素(2,1mg·L^-1)共同作用24 h。CCK-8法测定细胞增殖;ELISA法测定细胞分泌炎症因子IL-23;Real-time PCR法测定细胞内趋化因子CXCL1,CXCL2和CCL20以及β-防御素4(β-defensin4,DEFB4)的表达。 结果: 紫草素2,1 mg·L^-1能显著抑制IL-17A诱导的HaCaT细胞增殖,具有统计学意义(P<0.01);紫草素各浓度组均能减少IL-23分泌,并对细胞内CXCL1,CXCL2,CCL20和DEFB4的表达有一定的抑制作用。 结论: 紫草素能抑制IL-17A诱导的HaCaT细胞增殖和相关细胞因子的分泌,并可以通过抑制趋化因子募集白细胞,从而达到对银屑病的治疗作用。     

Shikonin and its derivatives inhibit the epidermal growth factor receptor signaling and synergistically kill glioblastoma cells in combination with erlotinib

Overexpression and mutation of the epidermal growth factor receptor (EGFR) gene play a causal role in tumorigenesis and resistance to treatment of glioblastoma (GBM). EGFR inhibitors such as erlotinib are currently used for the treatment of GBM; however, their efficacy has been limited due to drug resistance. New treatment strategies are therefore urgently needed. Shikonin, a natural naphthoquinone, induces both apoptosis and necroptosis in human glioma cells, but the effectiveness of erlotinib‐shikonin combination treatment as well as the underlying molecular mechanisms is unknown yet. In this study, we investigated erlotinib in combination with shikonin and 14 shikonin derivatives in parental U87MG and transfected U87MG.ΔEGFR GBM cells. Most of the shikonin derivatives revealed strong cytotoxicity. Shikonin together with five other derivatives, namely deoxyshikonin, isobutyrylshikonin, acetylshikonin, β,β‐dimethylacrylshikonin and acetylalkannin showed synergistic cytotoxicity toward U87MG.ΔEGFR in combination with erlotinib. Moreover, the combined cytotoxic effect of shikonin and erlotinib was further confirmed with another three EGFR‐expressing cell lines, BS153, A431 and DK‐MG. Shikonin not only dose‐dependently inhibited EGFR phosphorylation and decreased phosphorylation of EGFR downstream molecules, including AKT, P44/42MAPK and PLCγ1, but also together with erlotinib synergistically inhibited ΔEGFR phosphorylation in U87MG.ΔEGFR cells as determined by Loewe additivity and Bliss independence drug interaction models. These results suggest that the combination of erlotinib with shikonin or its derivatives might be a potential strategy to overcome drug resistance to erlotinib.     

分子印迹流动注射化学发光法测定紫草中紫草素

目的 建立分子印迹流动注射化学发光法定量分析紫草素的新方法。方法 在酸性条件下,紫草素对高锰酸钾-甲醛体系发光反应具有明显的增敏作用,以甲基丙烯酸为功能单体、乙二醇二甲基丙烯酸酯为交联剂合成紫草素的分子印迹聚合物,并将其作为分子识别物质,利用紫草素-高锰酸钾-甲醛化学发光体系,结合流动注射化学发光分析技术,建立测定紫草素的分子印迹流动注射化学发光分析方法。结果 体系的化学发光强度与紫草素质量浓度呈线性关系,其标准曲线为Y＝43.2 X＋12.68,r＝0.999 3,线性范围为1.20～80.0 μg/mL,检出限为0.36 μg/mL。结论 利用分子印迹流动注射化学发光分析法测定紫草中的紫草素简便、快速、准确。     

单向灌流法研究紫草素的大鼠在体肠吸收

目的:研究紫草素的大鼠在体肠吸收机制。方法:采用单向灌流模型,紫外分光光度法测定在体肠灌流紫草素的浓度变化,研究紫草素的吸收部位和吸收动力学特征。结果:紫草素在大鼠各肠段的吸收速率常数(Ka)、有效渗透系数(Papp)是结肠>空肠>十二指肠>回肠,且各肠段的Ka和Papp值均无显著性差异;灌流液中不同浓度紫草素的Ka,Papp均无统计差异。结论:紫草素在全肠道有不同程度的吸收,其中结肠吸收最好,药物浓度对紫草素的Papp和Ka值无影响,其吸收机制为被动扩散。     

紫草素及其衍生物诱导凋亡机制外的抗肿瘤机制研究进展

紫草素是从中药紫草中提取的小分子萘醌类化合物，具有明显抗肿瘤作用。紫草素抗肿瘤机制涉及多个靶点，除了传统抗凋亡机制外，还包括诱导肿瘤细胞发生坏死性凋亡、抑制拓扑异构酶、抑制丙酮酸激酶M2（PKM2）等。国内外抗肿瘤药物发展的战略要点之一是从天然产物中寻找高效低毒的活性成分，紫草素具有高效低毒作用，有望和其他化疗药物联合应用，实现化疗协同、增效、减毒作用。