2',4'-二羟基-3'-甲基-3-甲氧基查耳酮上调p21抑制人肝癌HepG2细胞的生长

目的 探讨2'',4''-二羟基-3''-甲基-3-甲氧基查耳酮(C20)对人肝癌HepG2细胞的体外抗肿瘤作用及其潜在的作用机制。方法 通过CCK-8法、集落形成实验、5-乙炔基-2''-脱氧尿苷(EdU)染色法检测C20对人肝癌HepG2细胞增殖的影响;通过彗星实验检测C20(10 μmol·L^-1)对HepG2细胞DNA损伤的影响;通过流式细胞术检测C20(5、10 μmol·L^-1)对HepG2细胞周期阻滞的影响;通过Hoechst染色和流式细胞术检测C20(5、10 μmol·L^-1)对HepG2细胞凋亡的影响。借助Western blotting法检测C20(5、10 μmol·L^-1)处理对HepG2细胞中与凋亡、DNA损伤、细胞周期阻滞相关蛋白表达水平的调控作用。结果 与对照组比较,C20显著抑制HepG2细胞的活力(P<0.001),给药48 h的半数抑制浓度(IC₅₀)为7.937 μmol·L^-1;5 μmol·L^-1 C20能够显著抑制HepG2细胞的集落形成能力(P<0.01);EdU染色结果显示5、10 μmol·L^-1的C20能够抑制人肝癌HepG2细胞的增殖能力;5、10 μmol·L^-1的C20显著诱导HepG2细胞G₂/M期阻滞(P<0.001);5、10 μmol·L^-1的C20显著促进HepG2细胞凋亡(P<0.001),并显著上调Caspas-3、Caspase-9以及PARP的剪切水平(P<0.01);10 μmol·L^-1的C20能够诱导HepG2细胞发生DNA损伤,并且5、10 μmol·L^-1的C20显著上调γH2AX、p21的蛋白水平(P<0.01)。结论 C20能够造成HepG2细胞发生DNA损伤,上调p21蛋白水平,导致细胞G₂/M期阻滞,并进一步诱发凋亡,发挥体外抗肝癌作用。     

HPLC测定当归中1-(3',4'-dihydroxycinnamoyl)-cyclopentane-2,3-diol的含量

目的 建立HPLC测定当归中1-（3'',4''-dihydroxycinnamoyl）-cyclopentane-2,3-diol含量的方法。方法 采用Inertsil ODS-3 C₁₈柱（4.6 mm×250 mm,5 μm）,流动相为乙腈-0.05%三氟乙酸水溶液梯度洗脱,流速为1.0 mL·min^-1,检测波长为325 nm,柱温为30℃。结果 1-（3'',4''-dihydroxycinnamoyl）-cyclopentane-2,3-diol进样量在0.023 36~1.168 0 μg（r=1.000 0）内与峰面积呈良好的线性关系,平均回收率为95.33%,RSD为1.88%。结论 该方法简便、准确、重复性好,可为当归药材的质量控制提供参考。     

鬼臼毒素聚合物胶团对人胶质瘤细胞的抑制作用

目的 合成鬼臼毒素聚合物胶团,评价其对人胶质瘤细胞的增殖抑制作用。方法 制备鬼臼毒素聚合物胶团,考察其理化性质,通过肿瘤细胞摄取实验,噻唑蓝（MTT）法检测其对U87细胞的增殖抑制作用。结果 鬼臼毒素聚合物胶团比游离药物鬼臼毒素对人胶质瘤细胞有更大的增殖抑制作用,显著增加肿瘤细胞内的药物浓度。结论 鬼臼毒素聚合物胶团对人脑胶质瘤细胞增殖有明显的抑制作用。     

7-二氟甲氧基-5,4'-二正辛烷氧基金雀异黄素钝化Pim-1对宫颈癌细胞增殖和侵袭的抑制作用

目的 检测7-二氟甲氧基-5,4''-二正辛烷氧基金雀异素(7-difluoromethoxyl-5,4''-di-n-octylygenistein,DFOG)对宫颈癌HeLa细胞增殖、迁移、侵袭的抑制作用及其机制。方法 体外培养宫颈癌HeLa细胞,用MTT法检测DFOG对HeLa细胞的增殖抑制作用;用PI染色FCM检测DFOG对HeLa细胞周期分布的影响;用Transwell法检测DFOG对HeLa细胞迁移及侵袭的抑制作用;用Western blotting、siRNA/cDNA转染检测DFOG对HeLa细胞增殖、迁移侵袭抑制作用的可能分子生物学机制。结果 DFOG在体外对HeLa细胞增殖、迁移、侵袭呈浓度依赖性的抑制作用,阻滞细胞周期于G1期,伴随着Pim-1蛋白表达下调,同时Pim-1下游蛋白Cyclin D、Cyclin E、Cyclin A表达下调,而p15和p21蛋白表达上调。用siRNA干扰沉默Pim-1基因,则DFOG对HeLa细胞增殖、迁移、侵袭的抑制作用明显加强;用Pim-1-cDNA转染HeLa细胞,则能部分抵消DFOG对细胞增殖、迁移、侵袭的抑制作用。结论 DFOG通过钝化Pim-1组织细胞与G1期而发挥其抑制宫颈癌HeLa细胞增殖、迁移和侵袭的作用。     

鬼臼毒素衍生物CIP-36诱导KBV 200细胞凋亡

目的：研究鬼臼毒素衍生物CIP-36对多药耐药人口腔鳞状上皮癌细胞KBV 200的抗肿瘤活性及其作用机制。方法：MTT法考察CIP-36对KBV 200体外增殖的抑制作用;Giemsa染色、DNA ladder和流式细胞仪等方法进行细胞凋亡检测;免疫荧光法观察CIP-36对细胞骨架的作用;western-blot法检测CIP-36对KBV 200细胞P-gp表达的影响。结果：CIP-36对KBV 200细胞有明显的抑制作用,IC₅₀值为（2.06±0.38）μmol / L,能够诱导细胞产生凋亡小体和DNA ladder。流式细胞检测到了细胞凋亡峰,并观察到细胞周期出现S/G₂+M期阻滞。Western-blot结果显示P-gp表达降低,并且观察到CIP-36可破坏KBV 200细胞的细胞骨架。结论：CIP-36可能通过降低P-gp的表达,破坏细胞骨架等多靶点克服KBV 200细胞株的多药耐药性。     

藏红花素联合顺铂对人宫颈癌HeLa细胞协同抑制作用的研究

目的 探索藏红花素联合顺铂对人宫颈癌HeLa细胞的协同抑制作用及相关调控机制。方法 取对数生长期人宫颈癌HeLa细胞,设置空白对照组（DMSO）、藏红花素组（400 μg·mL^-1）、顺铂组（5 μg·mL^-1）、联合组（藏红花素400 μg·mL^-1+顺铂5 μg·mL^-1）。干预48 h后,CCK-8检测HeLa细胞增殖抑制率,采用CompuSyn软件计算藏红花素与顺铂的联合指数（CI）,Annexin V-FITC染色法检测细胞凋亡,流式细胞术检测细胞周期分布,Western blotting检测激活型半胱氨酸天冬氨酸蛋白酶-3（Cleaved Caspase-3）、B细胞淋巴瘤/白血病-2（Bcl-2）、Bcl-2相关X蛋白（Bax）、细胞周期素D1（Cyclin D1）、周期蛋白依赖激酶2（CDK2）的表达。结果 与顺铂组比较,联合组细胞增殖抑制率显著升高（P<0.05）,CI为0.68,具有中度协同效应;细胞凋亡率显著升高（P<0.01）,G₀/G₁期细胞比例显著升高（P<0.05）,而G₂/M期比例显著降低（P<0.01）,Cleaved Caspase-3、Bax蛋白表达水平及Bax/Bcl-2比值均显著升高（P<0.05）,Cyclin D1、CDK2蛋白表达水平显著降低（P<0.01）。与空白对照组比较,藏红花素组G₀/G₁期细胞比例显著升高而G₂/M期比例显著降低（P<0.01）,Cleaved Caspase-3、Bax表达水平及Bax/Bcl-2比值均显著升高（P<0.01）,Cyclin D1、CDK2表达水平显著降低（P<0.05）。结论 藏红花素联合顺铂可协同抑制人宫颈癌HeLa细胞的增殖和生长,其作用机制可能与调控凋亡相关蛋白的表达从而促进细胞凋亡、阻滞细胞周期进程有关。     

HPLC-DAD法测定益脑胶囊中3,6'-二芥子酰基蔗糖、五味子醇甲和人参皂苷Rb1

目的 建立HPLC-DAD法同时测定益脑胶囊中3,6''-二芥子酰基蔗糖、五味子醇甲和人参皂苷Rb₁的方法。方法 采用Agilent Eclipe Zorbax XDB C₁₈柱（250 mm×4.6 mm,5 μm）;流动相：0.1%磷酸溶液–乙腈,梯度洗脱;检测器：DAD检测器;检测波长：203 nm（人参皂苷Rb₁）、249 nm（五味子醇甲）、321 nm（3,6''-二芥子酰基蔗糖）;体积流量：1.0 mL/min;柱温：室温;进样量：10 μL。结果 3,6''-二芥子酰基蔗糖、五味子醇甲和人参皂苷Rb₁分别在0.193～19.300、0.299～29.910、0.189～188.600 μg/mL线性关系良好,平均回收率分别为99.5%、99.7%、98.3%,RSD值分别为1.2%、1.1%、0.7%。结论 本法简便、准确、快速,适用于益脑胶囊中3,6''-二芥子酰基蔗糖、五味子醇甲和人参皂苷Rb₁的测定,为完善该产品的质量标准完善提供参考。     

4-O-卤代酰基-4′-去甲基表鬼臼毒素类似物的合成与抗肿瘤活性

为考察4′-去甲表鬼臼毒素C₄位上联结含卤素原子的酯化侧链时对化合物抗肿瘤活性的影响,设计并采用选择性酯化方法合成了9个新的4′-去甲基表鬼臼毒素酯化产物。其中标题化合物在L₁₂₁₀白血病肿瘤细胞与KB细胞的体外生长抑制试验中普遍表现出显著的抑制活性,大部分化合物活性超过依托泊甙。而普通脂酸酯的活性较弱。     

新型低氧还原剂Q39通过阻断HIF-1α转运引起肝癌Bel-7402细胞凋亡

目的 评价Q39低氧条件下诱导肝癌细胞Bel-7402细胞凋亡的抗肿瘤活性及其机制。方法 MTT法测定Q39对人肝癌细胞Bel-7402增殖抑制作用。PI染色法检测Q39诱导人肝癌细胞凋亡作用。免疫荧光法检测HIF-1α蛋白的转运和表达。结果 Q39在常氧和低氧下均抑制肝癌Bel-7402细胞的生长。Q39在低氧条件下促进Bel-7402肿瘤细胞凋亡。Q39通过抑制ERK1/2的磷酸化,明显抑制HIF-1α的转运。结论 Q39在低氧条件下通过抑制ERK1/2信号通路引起Bel-7402肿瘤细胞凋亡。     

4-S-(5-酰氨基-1,3,4-噻二唑-2-基)-4-脱氧-4′-去甲基表鬼臼毒素衍生物的合成与抗肿瘤活性

基于在4′-去甲基表鬼臼毒素母核C₄位上联结含有杂原子的芳香环取代基,以此考察其结构与活性关系的设想,设计并合成了10个标题化合物。体外L₁₂₁₀白血病细胞与KB细胞生长抑制试验结果表明,这类化合物有较强的抗肿瘤活性。其中化合物SIPI-92-1772,1774,1775,1776,1777与1779的活性超过临床用药依托泊甙。其余化合物活性与依托泊甙相当或略低。     

RP-HPLC测定4，5，2’-三吗啉酰氧基-2，5'-二氯二苯甲酮原料药的含量及有关物质

目的 建立测定原料药4,5,2''-三吗啉酰氧基-2,5''-二氯二苯甲酮（LF1）的含量及有关物质的RP-HPLC方法。方法 采用Diamonsil C₁₈（250 mm×4.6 mm,5 μm）色谱柱,乙腈-磷酸水（60：40,pH3.0）为流动相,检测波长230 nm,体积流量1 mL/min,柱温25℃。结果 主峰与杂质峰分离良好,LF1和杂质A分别在质量浓度1.0~100（r=0.999 8）和0.2~2.4 mg/L （r=0.999 6）线性关系良好,最低检测限分别为1和2 ng/mL,平均回收率分别为100.7%和102.0%。结论 本法简便、快速、准确,可用于LF1原料药的含量及有关物质的测定。     

Effects of local anesthetics on calmodulin-dependent guanylate cyclase in the plasma membrane of Tetrahymena pyriformis

A highly purified preparation of Tetrahymena calmodulin activated a membrane-bound guanylate cyclase by more than 40-fold. This activation of guanylate cyclase by calmodulin was inhibited completely by local anesthetics such as dibucaine, tetracaine, lidocaine and procaine at concentrations that had no appreciable effect on the activities of basal guanylate cyclase (without calmodulin) and adenylate cyclase. The inhibition by dibucaine of calmodulin-mediated activation of the enzyme activity was not reversed by calcium but was partially overcome by increasing the concentration of calmodulin. Kinetic analysis of local anesthetic-induced inhibition of activation of guanylate cyclase demonstrated a mixed type of antagonism. These results suggest the possibility that the inhibition of calmodulin-dependent guanylate cyclase resulted, in part, from interaction of the drugs with calmodulin.     

Structural analogs of 5'-methylthioadenosine as substrates and inhibitors of 5'-methylthioadenosine phosphorylase and as inhibitors of human lymphocyte transformation

5'-Deoxy-5'-methylthioadenosine (MTA) phosphorylase was purified 13.4-fold from human peripheral lymphocytes. The enzyme demonstrated normal Michaelis-Menten kinetics with Km values of 26 microM and 7.5 mM for the two substrates, MTA and phosphate, respectively. The rate of MTA degradation was temperature dependent, 47 degrees being the optimum temperature. Five structural analogs served as alternative substrates with Km values ranging from 31 to 53 microM while two compounds, 5'-deoxy-5'-methylthiotubercidin (MTT) (Ki = 31 microM) and adenine (Ki = 172 microM), were inhibitory. These same analogs were examined as inhibitors of mitogen-induced human lymphocyte blastogenesis. MTT was found to be the most effective inhibitor of lymphocyte transformation with an I50 of 80 microM.     

UPLC-TOF-MS法鉴定胀果甘草药渣中黄酮类成分

目的建立胀果甘草药渣中黄酮类成分的超高效液相色谱-高分辨飞行时间质谱(UPLC-TOF-MS)定性分析方法。方法 AgilentSB-C18柱(100mm×4.6mm,1.8μm);流动相乙腈-0.1%甲酸水溶液,梯度洗脱;体积流量0.4mL/min;柱温25℃;检测波长254nm。ESI离子源,飞行时间质谱检测器。对比自制对照品进行鉴别。结果共鉴定出8个黄酮类成分,分别为2’,4,4’-三羟基查耳酮、甘草查耳酮D、甘草查耳酮甲、4’-羟基-2’’,2’’-二甲基吡喃[5’’,6’’,6,7]黄酮、甘草黄酮C、光甘草酮、甘草黄酮B和kanzonolE。结论建立了一种简单、可靠的UPLC-TOF-MS方法对胀果甘草药渣中黄酮类成分进行了鉴定,对胀果甘草药渣综合利用有一定参考价值。     

Stimulatory effect of ionophores on adenosine 3',5'-monophosphate content in human mononuclear leukocytes

Ionophores A23187 and bromo-lasalocid ethanolate enhanced the cyclic AMP content in human mononuclear leukocytes. The maximum effect of A23187 with a 10-min incubation was found with 0.3–1.0μM concentrations with or without l-isoproterenol (1 μM) or prostaglandin E ₁ (pge ₁) (0.3 μM). The maximum effect after 5 min of incubation at 37° was observed with 0.05, 0.2 and 1 μm A23187. The effect of ionophore A23187 was enhanced by both aminophylline (1 mM) and isobutyl-methylxanthine (1 mM). Calcium (1 mM). aspirin (1 mM) and indomethacin (100 μM) decreased the stimulatory action of A23187. Bromo-lasalocid ethanolate increased cyclic AMP content in cells maximally at a 3 μM concentration with or without 0.3 μM pge ₁.     

Effects of phenothiazines on the membrane-bound guanylate and adenylate cyclase in tetrahymena pyriformis

The particulate-bound guanylate cyclase activity of Tetrahymena pyriformis was shown previously to be Ca²⁺-dependent and to be activated by an endogenous calmodulin-like protein (Tetrahymena Ca²⁺-binding protein, TCBP) [S. Nagao, Y. Suzuki, Y. Watanabe and Y. Nozawa, Biochem. biophys. Res. Commum.90, 261 (1979)]. Phenothiazine derivatives, such as chlorpromazine and trifluoperazine, that interact with calmodulin were found to inhibit the Ca²⁺-dependent guanylate cyclase activity and the TCBP-induced activation of the guanylate cyclase activity. Ethylene glycol-bis (β-aminoethyl ether)-N, N'-tetraacetic acid (EGTA), a Ca²⁺ chelator, also inhibited the activation of guanylate cyclase. However, the mechanisms by which EGTA and trifluoperazine act were different. The EGTA-induced inhibition could not be overcome by increasing the concentration of TCBP, whereas the trifluoperazine-induced inhibition could be overcome by increasing the concentration of TCBP, but not by increasing the concentration of Ca²⁺. These findings suggest that the mechanism by which trifluoperazine inhibits the activation of guanylate cyclase involves competition with TCBP.     

Increased thymidylate synthetase in 5-fluorodeoxyuridine resistant cultured hepatoma cells

A FdUrd resistant line of cultured mouse hepatoma cells has been obtained. The resistant cell line had 6- to 10-fold higher levels of thymidylate synthetase, but dihydrofolate reductase and thymidine kinase were unchanged. No impairment of FdUrd incorporation by the resistant cell line could be detected. The increased thymidylate synthetase in resistant cells had the same turnover number and I₅₀ for FdUMP as the enzyme found in sensitive cells, making it unlikely that a new gene product had been obtained. Sensitive cells could be completely rescued by the addition of thymidine, suggesting that the primary mode of drug action is to diminish thymidine metabolites. Resistant cells, removed from FdUrd for several generations, did not proliferate immediately upon reintroduction of the drug; however, loss of sensitivity was much more rapid than upon initial exposure. These results are interpreted in terms of a mechanism for resistance.     

Age related changes in cardiac and aortic phosphodiesterase activities in normotensive and hypertensive rats.

The activities of cAMP¹ and cGMP phosphodiesterase were studied in the aorta (freed of adventitia layer) and in the heart (ventricles) of normotensive and mincralocorticoid hypertensive rats of 8 or 16 weeks of age. The enzyme activities were determined at low (1 μM) and high (100 μM) substrate concentrations. The changes in activity were compared to the changes in organ weight, protein and DNA content. The increase in organ weight that occurred with both age and hypertensive treatment corresponded mostly to a marked elevation in protein content in the aorta, but not in the heart, where the DNA content increased without any significant variation in protein content. In both tissues. eGMP phosphodiesterase activity measured at low substrate concentration was sensitive to endogenous Ca²⁺-dependent activation and markedly increased with age. This increase was proportionally larger than the variations in DNA content of the tissues, but lower than those of total protein in the aorta. It could not be ascribed to an increase in the activator content of the tissues, which was in excess. By contrast. cGMP phosphodiesterase activity measured at high substrate concentration and cAMP phosphodiesterase activity, measured at either substrate concentration, were not sensitive to the Ca²⁺-dependent activation and did not undergo large changes with age except for a significant decrease in cAMP phosphodiesterase activity at high substrate concentration per mg heart cytosol protein. No relationship could be found between the elevation of blood pressure, due to age or to the influence of the mineralocorticoid treatment, and phosphodiesterase activities, which varied in a similar manner in control and hypertensive rats. The results are consistent with the view that a cGMP phosphodiesterase. which is sensitive to Ca²⁺-dependent endogenous activation, increases in aorta and heart cells with the age of the rat.