维生素A对C_(57)BL小鼠黑色素瘤肺转移的影响及其机理研究

本研究从免疫学角度观察了维生素A(V-A)对肺泡巨噬细胞(Mφ)功能的影响和体内抗肿瘤血道肺转移的作用。实验结果显示,V-A处理后小鼠肺泡Mφ细胞毒活性及其细胞表面补体C_3b受体功能均有所增强,小鼠肿瘤血道肺转移减少,且两者之间有较好的相关性。     

鲨鱼软骨提取物对肿瘤的抑制作用

鲨鱼软骨提取物（sharkcartilageactiveextract，SCAE）在体外细胞实验中，当浓度为50μg／ml时，对肿瘤细胞的抑制率是50．2％～60％。在小鼠移植瘤实验中表明，SCAE作用最佳的是分子量1×104～5×104部位。小鼠口服SCAE24～72mg／d的抑瘤率是54％～67％，小鼠注射SCAE6～18mg／d的抑癌率是67％～82．2％。SCAE有溶于水，用量小等特点。     

银杏外种皮提取物对C_(57)BL/6J小鼠Lewis肺癌转移的抑制作用及其机制

目的研究银杏外种皮提取物(GBEE)对小鼠Lewis肺癌转移的抑制作用及其作用机制。方法制备C57BL/6J小鼠Lewis肺癌转移模型,随机分为正常对照、模型对照、替加氟80 mg·kg-1(阳性对照)和GBEE 50,100和200 mg·kg-1治疗组。正常和模型对照组ig给予等体积生理盐水,给药组分别ig给予相应药物,每天1次,连续15 d。给药结束后第2天剥瘤称取瘤质量,计算抑瘤率;摘取肺组织,Bouin's液固定后于解剖显微镜下计数肺表面转移灶,计算肺癌转移率和抗转移率;放射免疫法测定血清Ⅳ型胶原(ColⅣ)和透明质酸(HA)的含量;免疫组织化学法检测移植瘤细胞CD44和nm23-H1蛋白的表达。结果 GBEE 50,100和200 mg·kg-1对C57BL/6J小鼠Lewis肺癌移植瘤生长具有明显的抑制作用(P<0.05,P<0.01),移植瘤瘤质量分别为2.6±0.4,2.3±0.4和(2.3±0.6)g,抑瘤率分别为21.3%,32.2%和29.6%。模型对照组小鼠Lewis肺癌转移率为70%,GBEE 50,100和200 mg·kg-1治疗组肺癌转移率分别为50%,30%和40%。与模型对照组比较,GBEE 100 mg·kg-1治疗组小鼠肺癌转移灶明显减少(P<0.01),抗转移率为87.5%;50和200 mg·kg-1无明显影响。与模型对照组比较,GBEE 50,100和200 mg·kg-1可明显降低小鼠血清中ColⅣ和HA含量(P<0.01),抑制小鼠Lewis肺癌移植瘤细胞CD44蛋白表达,并促进nm23-H1蛋白表达(P<0.05,P<0.01)。结论 GBEE对Lewis肺癌转移模型小鼠具有抗肿瘤转移作用,其机制可能与增加肿瘤转移抑制基因nm23-H1表达、抑制肿瘤细胞黏附分子CD44表达并降低血清ColⅣ和HA含量有关。     

鲨鱼软骨制剂抗肿瘤作用的研究

以鲨鱼软骨为原料,经盐酸胍抽提,丙酮分级沉淀,超滤,Sephadex G-75柱层折等步骤得到鲨鱼软骨制剂 1（SP1）和鲨鱼软骨制剂 2（SP2）。测定它们对肿瘤细胞和血管内皮细胞DNA合成的抑制效应,对小鼠移植瘤的抑癌作用,以及对小鼠脾脏和胸腺的影响。结果表明:SP1能同时抑制血管内皮细胞和直接抑制肿瘤细胞;SP2同时具有提高机体免疫功能、直控抑制肿瘤细胞和抑制血管内皮细胞的活性。整体实验说明它们都具有较强的抑制肿瘤生长的活性,对小鼠体重无明显影响,无明显毒副作用,显示了良好的应用前景。     

鲨鱼软骨粉对S_(180)荷瘤小鼠免疫细胞调节功能的影响

目的研究鲨鱼软骨粉(SCP)对S180荷瘤小鼠免疫细胞功能的影响。方法鲨鱼软骨粉300、200、100mg·kg-1小鼠灌胃给药10 d。MTT法检测其对S180荷瘤小鼠脾淋巴细胞增殖功能的影响;流式细胞仪检测T淋巴细胞亚群的变化;ELISA法测定荷瘤小鼠血清中细胞因子TNF-α、IFN-γ含量。结果 SCP能提高小鼠脾淋巴细胞的增殖活性;不同程度地提高小鼠脾细胞CD4+细胞数,增加CD4+/CD8+细胞比值;明显提高小鼠巨噬细胞的吞噬活性;促进外周血清中TNF-α和IFN-γ的分泌水平。结论 SCP能提高T细胞介导的细胞免疫应答,提高巨噬细胞调节免疫应答的功能,促进TNF-α、IFN-γ等细胞因子的分泌,从而发挥其抗肿瘤作用。     

苦参碱对C57BL/6J小鼠Lewis肺癌VEGF表达的影响

目的 研究苦参碱对小鼠Lewis肺癌的作用,并探讨其作用机制.方法 建立小鼠Lewis肺癌模型,将实验小鼠分为生理盐水组、不同剂量苦参碱组、环磷酰胺组,计算原发瘤抑制率及微血管密度;采用RT-PCR和Western blot法检测原发瘤组织VEGF mRNA和蛋白表达.结果 应用苦参碱各剂量组,小鼠原发瘤抑制率、微血管...     

用CAM技术评价鲨鱼软骨提取物抑制新生血管生长的活性

采用鸡胚绒毛尿囊膜（CAM）技术，检测了鲨鱼软骨提取物（SCAE）抑制新生血管生长的活性。其方法是将肿瘤组织、SCAE等样品接种在置于孵化5d鸡胚CAM膜上的硅环中，继续孵育2d后取膜，观察新生毛细血管生长情况，并采用Crums顺序进行评判。结果表明，SCAE能显著地抑制CAM的新生血管生长，并对BI。黑色素瘤促新生血管形成作用亦有非常显著的抑制作用。     

鲨鱼软骨粉对S_(180)荷瘤小鼠红细胞膜流动性的研究

目的从红细胞免疫的角度研究鲨鱼软骨粉的抗肿瘤作用机制,初步探讨鲨鱼软骨粉对S_(180)荷瘤小鼠红细胞膜流动性的影响。方法采用荧光分光光度法测定S_(-180)荷瘤小鼠红细胞膜流动性的变化;紫外分光光度法测定S_(-180)荷瘤小鼠红细胞膜酸性磷酸酶(ACP)的含量变化;十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDSPAGE)测定S_(180)荷瘤小鼠红细胞膜带3蛋白含量的变化。结果鲨鱼软骨粉能够提高S_(180)荷瘤小鼠红细胞膜流动性、酸性磷酸酶和带3蛋白的含量。结论鲨鱼软骨粉对S_(180)荷瘤小鼠红细胞膜流动性有显著增强作用。     

鲨鱼脑提取物对小鼠学习记忆的影响及毒性研究

采用东莨菪碱致小鼠记性障碍模型,通过迷宫实验法,观察了鲨鱼脑提取物对小鼠改善记忆的影响及其急性毒性实验.结果表明:鲨鱼脑提取物对东莨菪碱所致小鼠记忆障碍有明显改善作用,小鼠灌胃鲨鱼脑提取物的最大安全耐受量为成人常用量的675倍,提示临床用药安全,有较好的开发利用前景.     

鲨鱼软骨抗肿瘤制剂的效应及其作用机制

以鲨鱼软骨为原料，经盐酸胍抽提、丙酮分级沉淀、超滤等步骤得到鲨鱼软骨抗肿瘤制剂（SCATP）。采用放射免疫分析方法测定其对荷瘤小鼠血浆6－Keto－PGF1α和TXB2水平的影响，整装细胞扫描电镜技术测定SCATP对Hela细胞骨架的影响，常规方法测定SCATP对小鼠脾脏和胸腺的影响及对荷瘤小鼠的抑癌效应。结果显示，（1）当剂量达20mg／kg时，SCATP能使荷瘤小鼠血浆6－Keto－PGF1α非常显著下降（P＜0．01），使TXB2水平显著下降（P＜0．05）；（2）SCATP能使Hela细胞骨架发生凝聚或固缩，并有明显的浓度依赖关系，提示SCATP能抑制肿瘤细胞的分裂增殖及运动迁移；（3）SCATP能刺激小鼠脾脏和胸腺，并显著抑制实验动物肿瘤的生长。     

YIGSR聚合衍生物对B16黑色素瘤细胞实验性肺转移的抑制作用

目的 :研究Tyr-Ile-Gly-Ser-Arg(YIGSR )均叉、杂叉聚合肽的抗肿瘤转移作用。方法 :观察药物对B16黑色素瘤细胞实验性肺转移的影响。结果 :尾静脉接种B16黑色素瘤细胞第21天 ,46例对照组和实验组小鼠肺转移瘤灶形成比例100 %。10例对照组小鼠平均肺转移结节数105 5±78 2。与瘤细胞共注射的适宜剂量YIGSR均叉、杂叉肽可明显降低实验组小鼠的肺转移结节数 ,并呈一定的剂量依赖关系。其中 ,100μg～200μgYIGSR均叉和同剂量杂叉肽组肺转移结节数与对照组比较 ,P<0.05和P<0.01 ;50μg均叉肽与对照组比较 ,P<0.05。但受试合成肽未明显降低已形成肺转移小鼠的肺脏重量。结论 :YIGSR聚合衍生物有较强的抗肿瘤转移作用 ,其机制与瘤细胞栓塞、滞留于远隔靶器官的微血管中并增殖 ,瘤细胞穿出血管或淋巴管 ,在靶器官内形成微转移灶有关     

氨氯地平抑制小鼠黑色素瘤高转移细胞株B16体内转移的作用及相关机制研究

目的:研究不同剂量氨氯地平抑制小鼠黑色素瘤高转移细胞株B16转移的作用,并探讨其作用机制。方法:选取64只C57BL/6J小鼠,将黑色素瘤髙转移细胞株B16接种在小鼠腹股沟皮下(2×106个/只)。将接种后的小鼠以随机数字表法分为对照组和氨氯地平高、中、低剂量治疗组,对照组小鼠仅给予0.9%氯化钠注射液;治疗组小鼠给予不同剂量的氨氯地平治疗,分别为1 mg/kg(低剂量组)、3 mg/kg(中剂量组)和10 mg/kg(高剂量组)。观察各组小鼠肿瘤生长情况及身体情况;观察各组小鼠肿瘤肺转移情况,计算肺转移的结节及肿瘤抑瘤率;采用免疫组织化学法检测各组小鼠肿瘤组织中白细胞介素8(IL-8)蛋白表达水平;采用逆转录-聚合酶链反应(RT-PCR)检测各组小鼠肿瘤组织中IL-8的信使核糖核酸(mRNA)表达水平。结果:氨氯地平对小鼠黑色素瘤高转移细胞株B16的自发性肺转移有显著的抑制作用;治疗组小鼠肿瘤组织中IL-8蛋白表达均明显减弱,且随氨氯地平剂量的增加而减弱;治疗组小鼠肿瘤组织中IL-8的mRNA的表达明显低于对照组,且IL-8的mRNA的表达随氨氯地平剂量的增加而减弱。结论:氨氯地平对小鼠黑色素瘤高转移细胞株B16有一定的抑瘤和抑制肺转移作用,其作用可能与影响IL-8的表达有关。     

魟鱼软骨多糖对小鼠恶性黑色素移植瘤MMP-9表达的影响

目的:研究魟鱼软骨多糖(RCG)对小鼠恶性黑色素移植瘤基质金属蛋白酶-9(MMP-9)表达的影响。方法:体外培养黑色素瘤细胞(B16),接种B16细胞于C57BL/6小鼠右侧腋下部位,复制小鼠黑色素瘤模型。实验分为生理盐水(等容生理盐水)、环磷酰胺(CTX,60mg·kg-1)和魟鱼软骨多糖高、中、低剂量(700、300、100mg·kg-1)组,灌胃给药,每天1次,连续21d。观察肿瘤生长情况,计算原发瘤抑制率;采用Westernblot方法检测肿瘤组织中MMP-9的蛋白表达情况;采用RT-PCR方法检测MMP-9的基因表达情况。结果:与生理盐水组比较,魟鱼软骨多糖高、中、低剂量组小鼠原发瘤抑制率显著升高(P<0.01);魟鱼软骨多糖高、中、低剂量组MMP-9蛋白表达、基因表达显著降低(P<0.01)。结论:魟鱼软骨多糖能明显抑制小鼠黑色素瘤原发瘤的生长,可能与其抑制肿瘤MMP-9的蛋白表达和MMP-9mRNA的表达有关。     

国产云芝多糖对小鼠抗肿瘤免疫反应的促进作用

本文采用观察同一个体多种指标的方法,研究国产云芝胞内多糖对C57BL/6J/J小鼠体内的黑色素瘤B16的抗瘤作用及其促进荷瘤鼠抗肿瘤免疫反应的作用.结果表明,这种云芝多糖对黑色素瘤B16的抑瘤率为40.8%,与环磷酰胺合用对黑色素瘤B16人工肺转移的抑制率达84.4%;其抗瘤作用机理以拮抗肿瘤的免疫抑制作用,多方面有效地促进行瘤鼠的非特异性抗肿瘤免疫反应为主,对正常机体的免疫反应也有一定促进作用.     

Age-dependent stimulatory effect of desipramine and fluoxetine pretreatment on metastasis formation by B16F10 melanoma in male C57BL/6 mice

Although recent data may provide theoretical support for the preventive use of antidepressants in cancer patients, so far no study has demonstrated the clinical benefits of such strategies in the general population of cancer patients [39, 41]. Moreover, an association between antidepressant use and the risk of tumor promotion could neither be excluded nor established.The aim of this study was to compare the effect of desipramine (a tricyclic antidepressant, TCA) and fluoxetine (a selective serotonin reuptake inhibitor, SSRI) on tumor growth of the mouse B16F10 transplanted melanoma in “young” 6–9 month old and “aged” 18–23 month old male C57BL/6 mice. Drugs were administered daily at a dose of 10 mg/kg, ip, for two weeks and tumor cells were inoculated 2 h after the last antidepressant administration. Control animals were treated with saline. Tumor growth was significantly slower in aged than in young saline-treated control animals. Pretreatment with desipramine dramatically promoted metastasis formation and increased mortality rate but inhibited primary tumor growth in young males. On the other hand, both antidepressants increased primary tumor growth in aged animals, whereas metastasis was only moderately promoted. To determine the effect of antidepressant drug pretreatment and tumor progress on some parameters of cell-mediated immunity (proliferative activity and cytokine production by splenocytes) and angiogenesis, vascular endothelial growth factor (VEGF) and metalloproteinase (MMP)-9 plasma levels were established. The prometastatic effect of desipramine in young animals was connected with an increase of VEGF and MMP-9 plasma levels.     

Formulation of plumbagin loaded long circulating pegylated liposomes: in vivo evaluation in C57BL/6J mice bearing B16F1 melanoma

Context and Objective: Plumbagin (2-methyl, 5-hydroxy, 1, 4-naphthoquinone), an anticancer agent is encapsulated either as conventional or long circulating liposomal formulations to enhance its biological half-life and antitumor efficacy.

Methods: The liposomes were prepared by thin film hydration method and in vitro characterization was carried out to examine the particle size, zeta potential, drug encapsulation efficiency and in vitro release. The optimized formulations were tested for pharmacokinetic and pharmacodynamic efficacy against mice bearing B16F1 melanoma. Also in vivo toxicity studies were carried out.

Results and Discussion: The optimum particle size and entrapment efficiency was observed at drug to lipid molar ratio of 1:20. The in-vitro release of plumbagin from the liposomal formulations in phosphate-buffered saline (pH 7.4) showed biphasic release with an initial burst release followed by sustained release phase. Elimination half life (T_1/2) of pegylated, conventional and free plumbagin was 1305.76?±?278.16, 346.87?±?33.82 and 35.89?±?7.95?min respectively. Further, plumbagin exhibited better antitumor efficacy in vivo when administered as long circulating liposomes with no signs of normal tissue toxicity.

Conclusion: It can be concluded that the pegylated liposomes could provide a promising parenteral platform for plumbagin with enhanced plasma half-life and therapeutic efficacy.     

Differential Toxicity of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) in C57BL/6J Mice Congenic at the Ah Locus

Differential Toxicity of 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) in C57BL/6J Mice Congenic at the Ah Locus. BIRNBAUM,L. S., MCDONALD, M. M., BLAIR, P.C., CLARK, A. M., AND HARRIS,M. W. (1990). Fundam. Appl. Toxicol 15, 186–200. The acutetoxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was examinedin male C57BL/6J mice differing only at the Ah locus. Wild typemice (Ah^b/b; "b/b") were treated once with 0, 50, 100, 200,300, and 400 eg TCDD/kg po while congenic mice (Ah^d/d; "d/d")received a single dose of 0, 400, 800, 1600,2400, and 3200µgTCDD/kg. Mice were checked daily, weighed twice a week, andthose that survived, killed 35 days post-treatment. The LD5Ovalues were 159 and 3351 µg/kg for b/b and d/d mice, respectively.Mean time to death was 22 days and was independent of dose andgenotype. Decrease in body weight gain was noted in both strains5 days after treatment and occurred at doses 100 µ/kgin b/b mice and 1600 µg/kg in d/d mice. Dose-related increasesin liver weight (both absolute and relative to body weight)and decreases in thymus, spleen, testes, and epididymal fatpad weights were observed at 8–24–fold higher dosesin d/d than in b/b mice. A dose-related increase in segmentedneutrophils was observed in both strains. Serum chemistry valuesindicated that 8–24x greater doses of TCDD were neededto elevate sorbitol dehydrogenase, alanine aminotransferase,and 5'-nucleotidase and to decrease total and esterifled cholesterolin d/d than in b/b mice. Few effects were seen on total bileacids, serum triglycerides, glucose, or nonesterifled cholesterol.In the liver, hepatocellular cytomegaly, fatty change, and bileduct hyperplasia occurred in both strains in a dose-relatedmanner, as did thymic and splenic atrophy. Necrosis of germinalepithelium in the testes and edema in the stomach submu cosaoccurred at acutely toxic doses. These lesions also occurredat doses 8–24x greater in did than in b/b mice. Thus,the spectrum of toxicity is independent of the allele at theAh locus, but the relative dose needed to bring about variousacute responses is approximately 8–24x greater in congenicmice homozygous for the "d" allele than for the wild type animalscarrying two copies of the "b" gene.     

Dose-related effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in C57BL/6J and DBA/2J mice

The dose-related effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were studied in B6D2F1/J (B6D), C57BL/6J (C57), and DBA/2J (DBA) mice. A 14-fold difference in lethality was observed in C57 and DBA mice, based upon 30-day LD50 values of 182 and 2570 micrograms TCDD/kg body wt, respectively. The 30-day LD50 for B6D mice was 296 micrograms TCDD/kg body wt. A progressive loss of body weight in all strains of mice was observed during the 30-day LD50 studies, with maximal weight losses of 24.7, 34.0, and 33.4% prior to death of C57, B6D, and DBA mice, respectively. In separate experiments, it was found that decreased feed consumption did not contribute to weight loss in C57 mice exposed to lethal or sublethal doses of TCDD until the animals were moribund. Time-course studies in C57 mice treated with 200 micrograms TCDD/kg body wt indicated that decreases in serum glucose and triglyceride concentrations and increases in hepatic triglyceride content occurred within 4 to 8 days of exposure, and were maximally altered within 17 to 21 days postexposure, concomitant with a 25% body weight loss. C57 mice fasted for 24 to 96 hr lost 18% of body weight and also exhibited alterations in glucose and lipid parameters; however, these changes were substantially different than the effects of TCDD exposure. In concert, these observations demonstrate that decreased feed consumption (hypophagia) does not account for weight loss and changes in carbohydrate and lipid metabolism in TCDD-treated C57 mice. Dose-response experiments resulted in comparable changes in glucose and lipid parameters when DBA mice were exposed to 10-fold higher doses of TCDD than C57 mice. Parallel LD50 responses and parallel changes in carbohydrate and lipid metabolism, at 10- to 15-fold differences in dose range, are indicative of a common mechanism of toxicity in TCDD-treated C57 and DBA mice.     

Nitric Oxide and Carbon Monoxide Act as Inhibitory Neurotransmitters in the Longitudinal Muscle of C57BL/6J Mouse Distal Colon

The present study was designed to identify the inhibitory neurotransmitters mediating nonadrenergic noncholinergic relaxation in the longitudinal muscle of C57/BL mouse distal colon. Relaxation induced by electrical field stimulation (EFS) was recorded isotonically in the presence of atropine and guanethidine. Cyclic guanosine-3′,5′-monophosphate (cyclic GMP) content was measured by radioimmunoassay. EFS-induced relaxation was inhibited by nitro-l-arginine (l-NNA) and Sn (IV) protoporphyrin dichloride IX (SnPP-IX), a nitric oxide (NO) and carbon monoxide (CO) synthase inhibitor, respectively. A combination of both inhibitors produced an additive effect. ODQ, a soluble guanylate cyclase inhibitor, inhibited EFS-induced relaxation. NOR-1, a NO donor, and carbon monoxide-releasing molecule-2 (CORM-2), a CO donor, treatment relaxed the distal colon and increased cyclic GMP content. The effects of NOR-1 and CORM-2 were inhibited by ODQ. KT5823, a cyclic GMP–dependent protein kinase inhibitor, inhibited EFS-induced relaxation. EFS-induced relaxation in the presence of KT5823 was further inhibited byl-NNA, but not by SnPP-IX. In addition, KT5823 inhibited CORM-2–induced relaxation, but not NOR-1–induced relaxation. H89, a cyclic AMP–dependent protein kinase inhibitor, inhibited EFS-induced relaxation, and EFS-induced relaxation in the presence of H89 was further inhibited byl-NNA. These results suggested that NO and CO function as inhibitory neurotransmitters in the longitudinal muscle of C57BL mouse distal colon.