海南哥纳香醇甲(GHM-10)对体外L1210细胞的抗肿瘤活性

用体外培养法研究GHM-10对L1210细胞生长的抑制作用和作用机制。结果表明,L1210细胞在用GHM-10处理1h,24h和7d后,IC₅₀依次为6.85,3.32和1.59μg·ml^-1,提示GHM-10有非时相特异性细胞毒药物的特性。在用GHM-10 1～2μg·ml^-1作用24h后,L1210细胞的增长率和有丝分裂指数下降,细胞核形态发生变化,但活细胞率仍保持在96%以上,提示GHM-10主要抑制细胞的增殖。用流式细胞计对L1210细胞进行细胞周期动力学的分析表明,GHM-10可在一定程度上阻断G₁期细胞向S期移行,还可增加L1210细胞的膜流动性。     

海南哥纳香醇甲GHM-10对L1210细胞DNA分子结构及拓扑异构酶II活性的影响

目的： 研究海南哥纳香醇甲（GHM-10）抑癌细胞DNA合成的作用机制。 方法： 用单细胞凝胶电泳法检测GHM-10对L1210细胞DNA分子的损伤,碱洗脱法测定GHM-10对L1210细胞DNA单链长度的影响,用GHM-10对超螺旋pUC18 DNA的解旋能力测定它对DNA拓扑异构酶II活性的影响。 结果： L1210细胞用GHM-10 (4～10) μg.ml^-1处理4.5 h后,DNA分子受损,表现为电泳后在荧光显微镜下可见彗星状拖尾。GHM-10 (4～25) μg.ml^-1处理L1210细胞5 h, 可引起DNA单链断裂。 L1210细胞或从L1210细胞分离的蛋白质在用GHM-10处理后,DNA拓扑异构酶II的活性均被抑制。结论： GHM-10可引起L1210细胞DNA分子损伤; 无论在细胞内还是细胞外,GHM-10可抑制拓扑异构酶II的活性。     

海南粗榧新碱衍生物HH07A的抗肿瘤作用

用细胞生长曲线测定法及软琼脂集落形成分析法研究了HH07A对几种肿瘤及正常细胞生长的影响。结果表明,1.5ug·ml^-1及3μg·ml^-1HH07A能分别明显抑制L1210和HL-60细胞的生长。3种肿瘤细胞对HH07A的敏感性依次为L1210>KB>HL-60,而正常小鼠粒系祖细胞GM-CPC对药物的敏感性则低于前三者,且HH07A3.5μg·ml^-1对HL-60细胞无分化诱导作用。HH07A对腹水型L1210白血病小鼠、S180小鼠均有较明显的治疗作用,使L1210荷瘤小鼠、S180荷瘤小鼠存活时间延长。也能抑制S180实体瘤的生长。     

从海南哥纳香中分离的一种新化合物──海南哥纳香醇甲的抗肿瘤作用

体外用细胞生长曲线测定法、MTT试验、软琼脂集落形成分析法,及体内对移植性肿瘤实验,研究了海南哥纳香醇甲(GHM-10)的抗肿瘤作用,结果表明:GHM-10对肿瘤细胞有较强的抑制作用,IC₅₀在2μg·ml^-1左右;对正常细胞影响较小,骨髓祖细胞的敏感性则更低;耐药的KB/VCR200细胞及其亲本KB细胞具有相似的敏感性。GHM-10对HL-60细胞无分化诱导作用。GHM-10对实体型肝癌H22小鼠、Lewis肺癌小鼠及腹水型S180小鼠均有明显的治疗作用。     

海南粗榧新碱衍生物HH07A对体外L1210细胞的杀伤作用

体外培养的小鼠L1210细胞被HH07A2μg·ml^-1作用24h后,与对照组细胞相比,其细胞数不再增长,有丝分裂数及集落形成率下降,细胞形态及细胞周期动力学均发生一定的变化。且HH07A大剂量短期作用抑制Ll210细胞集落形成的效率高于低剂量持续作用。     

商陆多糖Ⅱ体外对小鼠脾细胞增殖及产生集落刺激因子的影响

用[³H]TdR参入法检测小鼠脾细胞增殖能力及产生集落刺激因子(colony stimulating factor. CSF)含量.证明商陆多糖Ⅱ(PAP-Ⅱ)在31～500 μg·m^-1范围内显著促进小鼠稗细胞增殖。PAP-Ⅱ,31～125 μg·ml^-1可剂量依赖性地促进Con A(1,2.8μg·ml^-1),LPS(3,10,30 μg·ml^-1)诱导的淋巴细胞细咆增殖,随着PAP-Ⅱ剂量加大,对丝裂原诱导的淋巴细胞增殖反呈抑制作用。PAP-Ⅱ。10～500μg·ml^-1呈剂量及时间依赖性地促进脾细胞产生CSF,其最适剂量为100 μg·ml^-1。最佳时间为5 d,提示PAP-Ⅱ能增强免疫及促进造血功能。     

二甲双胍缓释片人体药代动力学及其相对生物利用度

目的 研究国产盐酸二甲双胍缓释片在人体药代动力学行为并与普通片进行等效性评价比较,并估算其药代动力学参数。方法 20名受试者分两组交叉服用缓释片和普通片,用RP-HPLC法测定血浆中药物浓度,并估算相应的药动学参数。结果 单剂量口服1000mg缓释片和普通片后估算的AUC_0-24分别为11.95±2.62μg·h^-1·ml^-1和10.72±2.23μg·h^-1·ml^-1;C_max分别为1.50±0.22μg·ml^-1和2.34±0.30μg·ml^-1;T_max分别为3.38±0.8h和1.61±0.32h;t_1/2分别为4.94±0.47h和3.20±0.38h;多剂量1000mg·d^-1时AUC_ss分别为15.04±3.01μg·h^-1·ml^-1和14.51±2.69μg·h^-1·ml^-1;C_max分别为1.68±0.25μg·ml^-1和1.60±0.26μg·ml^-1;C_min分别为0.15±0.03μg·ml^-1和0.12±0.04μg·ml^-1;Cav分别为0.62±0.13μg·ml^-1和0.61±0.11μg·ml^-1;T_max分别为3.61±0.60h和1.88±0.38h;AUC_0-24和AUC_ss经对数转换后方差分析和双单侧t检验，显示两制剂吸收程度生物等效。结论受试制剂和参比制剂吸收程度生物等效，但具有缓释特性。盐酸二甲双胍缓释片的相对生物利用度单剂量时为（111.5±8.3）%，多剂量时为（103.6±9.2）%。     

人参皂甙Rh2体外对小鼠黑色素瘤细胞的分化诱导作用

体外实验证明人参皂甙Rh₂在10μg·ml^-1的浓度下能明显抑制B₁₆细胞的生长,并呈浓度依赖性,其IC₅₀为4.1μg·ml^-1。Rh₂在10μg·ml^-1浓度下对B₁₆细胞有较强的分化诱导作用,表现为黑色素生成能力明显增加;形态向上皮样细胞分化;细胞呈网状结构;黑色素颗粒增多,生长变缓慢。细胞动力学研究结果表明,Rh₂可使B₁₆细胞阻断在G₁期。提示Rh₂对B₁₆细胞具有分化诱导作用。     

(+),(-)和(±)棉酚在雌大鼠抗早孕作用的研究

妊娠第6～9天大鼠,分别ig(±)和(-)棉酚80mg·kg^-1·d^-1和40mg·kg^-1·d^-1,结果有明显的抗早孕作用。然而(+)棉酚40mg·kg^-1·d^-1对大鼠生育无明显影响。(-)棉酚30μg·ml^-1能抑制体外培养黄体细胞孕酮的分泌。(+)棉酚10μg·ml^-1能促进黄体细胞分泌孕酮。hCG1IU·ml^-1能明显刺激体外培养颗粒细胞孕酮的分泌。(±)棉酚10和30μg·ml^-1皆能明显降低颗粒细胞对hCG的反应性。     

HPLC法测定国产洛索洛芬钠片人体相对生物利用度

目的 建立人血浆中洛索洛芬钠浓度的HPLC测定方法,研究健康受试者口服国产洛索洛芬钠片的药代动力学,以进口洛索洛芬钠片作为参比制剂,计算两制剂的相对生物利用度,判断两种制剂是否等效。方法 血浆样品加入内标后经三氯乙酸沉淀蛋白、涡旋、离心,吸取上清液进样。色谱柱为Shimadzu VP-ODS(150mm×4.6mm i.d.,5μm C₁₈),流动相为0.05mol·L^-1磷酸二氢钾-甲醇(27∶73)(v/v),紫外检测波长230nm。测定了20名受试者单剂量口服两种洛索洛芬钠片60mg后血药浓度时间过程。结果 最低检测浓度0.2μg·ml^-1,回收率大于80%,日间和日内的变异系数小于10.5%,线性范围为0.2～12.0μg·ml^-1(r=0.9998),符合生物样品分析的要求。主要药动学参数分别为:国产洛索洛芬钠片:t_1/2为1.39±0.15h,AUC_0-6h 10.71±1.45μg·h·ml^-1,C_max7.23±1.02μg·ml^-1,t_max0.4±0.1h；参比制剂t_1/2为1.41±0.15h,AUC_0-6h 10.46±1.32μg·h·ml^-1,C_max7.49±1.26μg·ml^-1,t_max0.4±0.1h。结论 建立的HPLC法简单快速，定量可靠准确，适合于洛索洛芬钠临床研究。洛索洛芬钠受试制剂的相对生物利用度为（103.2±15.1）%。经统计学分析，两制剂生物等效。     

Anticancer effect of Howiinol A and its mechanism of action

Howiinol A (GHM-10) is a kind of phenylethylene pyrone compounds isolated from Goniothalamus howii. By using the techniques of cell growth curve determination, MTT test, soft agar colony assay and experimental therapy of transplantable tumors in mice, it is found that GHM-10 exerts potent inhibitory effect on cancer cells but its influence on normal cells is relatively slight; the sensitivity of a drug-resistant cell line, KB/VCR 2000, to GHM-10 is similar to its parent cell line KB. Remarkable therapeutic effect can be seen in mice bearing H22 hepatoma and Lewis lung cancer and in mice with ascetic sarcoma 180 when GHM-10 is orally or intraperitoneally administered.

The IC₅₀s of L1210 cells treated with GHM-10 for 1 and 24 h are 6.85 and 3.32 μg·ml^-1 respectively. The ratio of IC₅₀ 1 h and IC₅₀ 24 h is only 2.06, indicating that the action of GHM-10 is conformed to a cell cycle non-specific cytotoxic agent. By using trypan blue exclusive test and morphological examination, it is demonstrated that the main effect of GHM-10 is to inhibit the cell proliferation. Flow cytometery technique is used to analyze the cell cycle of L1210 cells. The results show that to some extent, GHM-10 blocks the cell cycle transition from G1 phase to S phase. By using [³H] labeled precursor incorporation technique, it is shown that GHM-10 significantly suppresses the biosynthesis of DNA, RNA and protein in L1210 cells, and the DNA synthesis is mostly affected. At 1 h after the cells were treated with GHM-10, these inhibitory effects have already been irreversible, suggesting that GHM-10 may cause structural damage on DNA molecules. However, GHM-10 is unable to intercalate into DNA molecules or to destroy its structure directly. By using single cell gel electrophoresis and alkaline elution technology, it is confirmed that GHM-10 causes DNA molecule damage and single strand breakage in L1210 cells. Further studies show that GHM-10 markedly inhibits DNA dehelix induced by DNA topoisomerase II both inside and outside the cells, indicating that GHM-10 is acting as an inhibitor of DNA topoisomerase II.     

4—（4“—（2”,2“,6”,6“—四甲基哌啶氮氧自由基）...

The antitumor activity of GP-7, a new spin-labeled epipodophyllotoxin, was studied by liquid scintillation spectrometry. There were many similarities between GP-7 and etoposide. Both GP-7 and etoposide inhibited the incorporation of [3H]TdR, [3H]UR, and [3H]Leu into DNA, RNA, and protein synthesis in leukemia 7712 cells. The inhibition correlated with drug concentration and duration. IC50 of GP-7 and etoposide on DNA synthesis at 24 h were 0.21 and 0.37 micrograms.ml-1, respectively. The inhibition of GP-7 or etoposide on DNA synthesis retained even after the drug were washed out for 3 h. GP-7 and etoposide caused DNA single-strand breaks, with a well concentration-response relationship. These data suggest that the inhibition of DNA synthesis by GP-7 or etoposide is likely due to the damage of DNA template and breaking of single-strand DNA.     

4-[4″-(2″,2″,6″,6″-四甲基哌啶氮氧自由基)氨基]-4′-去甲表鬼臼毒对L1210细胞系增殖、克隆形成和DNA合成的影响

新合成的鬼臼毒自旋标记衍生物4-(4″-(2″,2″,6″,6″-四甲基哌啶氮氧自由基)氨基)-4′-去甲表鬼臼毒(GP-7)显著抑制体外培养的L1210细胞生长。抑制作用和浓度及处理时间正相关,作用特点和鬼臼乙叉甙(VP-16)相似,24,48hIC_(50)分别为1.51和0.13μmol/L。GP-7和VP-16对L1210细胞软琼脂克隆形成均有抑制作用,且有浓度依赖性,IC_(50)分别为3.29和2.82μmol/L。GP-70.08～100μmol/L对L1210细胞DNA合成抑制率为18.4～80.7％。本文结果表明GP-7体外抗肿瘤作用与VP-16相似。     

Effect of the dialdehyde derivative of 5'-deoxyinosine on pyrimidine deoxyribonucleoside metabolism in L1210 cells

The effects of the dialdehyde derivatives of inosine (Inox) and 5'-deoxyinosine (5'-dInox) on L1210 cells were compared. The growth of L1210 cells was inhibited to a greater extent by 5'-dInox than by Inox. The increased inhibition of L1210 cell growth by 5'-dInox was also reflected by the increased inhibition of the incorporation of precursors into RNA, DNA and proteins. Even though 5'-dInox was a more potent inhibitor, Inox accumulated in the L1210 cells to levels 4- to 5-fold greater than 5'-dInox. The metabolism of [5-3H]deoxycytidine and [5-3H]deoxyuridine by L1210 cells in culture, in the presence of Inox or 5'-dInox, indicated that dCMP deaminase was an intracellular site of action for 5'-dInox. The dCMP deaminase activity in cell-free extracts prepared from 5'-dInox-treated cells was reduced markedly. This decrease in activity was not reversed by increased substrate concentrations nor was the activity subject to allosteric activation by dCTP. Deoxyuridine and deoxycytidine were able to reverse the effects of 5'-dInox on the inhibition of L1210 cell growth.     

Molecular basis of the antineoplastic activity of 3'-amino-3'-deoxythymidine

3'-Amino-3'-deoxythymidine decreased the incorporation of [2-14C]thymidine into DNA of L1210 cells in vitro, and produced an accumulation of [2-14C]thymidine di- and triphosphate. The extent of these effects varied with the amount of recovery time after removal of 3'-amino-3'-deoxythymidine prior to addition of labeled thymidine. The distribution of radioactivity in the acid-soluble fraction derived from [3H]3'-amino-3'-deoxythymidine was as follows: 50% as 3'-amino-3'-deoxythymidine, 20% as the monophosphate, 10% as the diphosphate, and 20% as the triphosphate derivatives. No incorporation of [3H]3'-amino-3'-deoxythymidine into L1210 DNA could be detected. 3'-Amino-3'-deoxythymidine-5'-triphosphate is a competitive inhibitor against dTTP with a Ki of 3.3 microM, whereas the Km for dTTP was 8 microM using activated calf thymus DNA as the template and DNA polymerase-alpha. These data indicate that a major site of inhibition by 3'-amino-3'-deoxythymidine is inhibition of the DNA polymerase reaction.     

Cytotoxicity of cinnamic aldehyde on leukemia L1210 cells

Cytotoxic effect of cinnamic aldehyde (CA) on L1210 mouse leukemia cells was tested. Addition of CA in Fischer's medium at 4.8 micrograms/ml could inhibit the growth of L1210 by 50 per cent. The terminal aldehyde-group of CA molecule was found to be responsible to the inhibition. Experiments of incorporating [3H]-uridine, [3H]-thymidine, and [3H]-leucine by the cells revealed that the syntheses of protein, DNA, and RNA were suppressed by the presence of CA in the culture solution with potency appeared in that order. The inhibitory effect of CA on glycolysis was insignificant. Direct reaction between aldehyde-groups of CA molecules and sulfhydryl-groups of cell components was proved. The results suggested that CA inhibited L1210 cells by blocking protein synthesis through trapping sulfhydryl-containing amino acids in the cell.     

Reversal of the cytotoxicity of 3'-amino-3'-deoxythymidine by pyrimidine deoxyribonucleosides.

Mammalian cell replication is strongly inhibited by 3′-amino-3′deoxythymidine (3′-aminothymidine). This cytotoxieity can be specifically prevented or reversed by pyrimidine 2′-deoxyribonucleosides. The addition of 50 μM 2′-deoxycytidine to L1210 cells treated with 10 μM 3′ the population doubling time from about 38 hr to 17 hr. The control cells doubled every 13 hr. Another cytotoxic effect produced by 3′-aminothymidine is a dose- and time-dependent increase in cell volume. 2′-Deoxycytidine can effectively prevent and reverse this increase. 3′-Aminothymidme appears to be a potent selective inhibitor of DNA synthesis in L1210 cells. The incorporation of [³H]thymidine into DNA was inhibited by 50 per cent at 1 μM 3′-aminothymidine, a concentration which reduced L1210 replication by about 65 per cent. The rate of incorporation of [³H] adenine into DNA, another measure of DNA synthesis, was reduced similarly by 3′-aminothymidine. and 2′-deoxycytidine eliminated this inhibition as well. An effect on RNA or protein synthesis was not detected. The incorporation of [³H] uridine or [³H] adenine into RNA, or of tritiated amino acids into protein, was not reduced by 25 μM 3′-aminothymidine. These results suggest that selective disruption of DNA metabolism may account for the cytotoxicity of 3′-aminothymidine.