汉防己甲素及克矽平对矽肺大鼠Ⅰ型和Ⅲ型胶原mRNA的影响

汉防己甲素（汉甲）及克矽平（Ｐｏｌｙｖｉｎｙｌｐｙｒｉｄｉｎｅ－Ｎ－Ｏｘｉｄｅ,ＰＶＮＯ）是目前较为有效的抑制矽肺纤维化的药物。本文研究了其对胶原ｍＲＮＡ水平的影响．斑点杂交实验表明大鼠接尘６０天和１２０天后α１（Ⅰ）及α１（Ⅲ）ｍＲＮＡ水平明显上升,经汉甲或克矽平治疗１个月或３个月后,胶原ｍＲＮＡ水平明显下降。原位杂交结果表明胶原ｍＲ－ＮＡ银颗粒与细胞性结节和增厚的肺泡壁的成纤维细胞分布重合。汉甲或克矽平治疗后银颗粒数下降。提示汉甲及克矽平对矽肺进程中的胶原基因表达增强有抑制作用。     

Bisbenzylisoquinoline alkaloids and P-glycoprotein function: A structure activity relationship study

Conflicts with the notion that specific substrate interactions were required in the control of reaction path in active transport systems, P-glycoprotein showed extraordinarily low specificity. Therefore, overexpression P-glycoprotein excluded a large number of anticancer agents from cancer cells, and multidrug resistance happened. Several kinds of bisbenzylisoqunoline alkaloids were reported to modulate P-glycoprotein function and reverse drug resistance. In order to provide more information for their structure activity relationship on P-glycoprotein function, the effects of tetrandrine, isotetrandrine, fangchinoline, berbamine, dauricine, cepharanthine and armepavine on the P-glycoprotein function were compared by using daunorubicin-resistant leukemia MOLT-4 cells in the present study. Among them, tetrandrine exhibited the strongest P-glycoprotein inhibitory effect, followed with fangchinoline and cepharanthine, and subsequently with berbamine or isotetrandrine. However, dauricine and armepavine showed little influence on the P-glycoprotein function. These data revealed that the 18-membered ring of the bisbenzylisoquinoline alkaloids maintained the P-glycoprotein inhibitory activity, suggesting that double isoquinoline units connected by two oxygen bridges were indispensable. Moreover, stereo-configuration of bisbenzylisoquinoline 3D structures determined their inhibitory activities, which provided a new viewpoint to recognize the specificity of binding pocket in P-glycoprotein. Our data also indicated that 3D chemical structure was more sensitive than 2D to predict the P-glycoprotein inhibitory-potencies of bisbenzylisoqunoline alkaloids.     

Tetrandrine enhances radiosensitivity through the CDC25C/CDK1/cyclin B1 pathway in nasopharyngeal carcinoma cells

The increasing resistance of nasopharyngeal carcinoma to irradiation makes the exploration of effective radiosensitizers necessary. Tetrandrine is known to be an antitumor drug, but little is known regarding its radiosensitization effect on nasopharyngeal carcinoma. We investigated the effect of combined treatment of irradiation and maximum non-cytotoxic doses of tetrandrine on the nasopharyngeal carcinoma cell lines CNE1 and CNE2. The maximum non-cytotoxic doses of tetrandrine in CNE1 and CNE2 cells were assessed using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The radiosensitization of cells receiving the maximum non-cytotoxic doses of tetrandrine was assessed by evaluating cell proliferation and DNA damage repair using MTT, clonogenic, comet assays and detection of caspase-3 and phosphorylated histone H2AX (γ-H2AX). The cell cycle was assessed by flow cytometry, and protein expression was detected by western blot analysis. The maximum non-cytotoxic doses of tetrandrine in CNE1 and CNE2 cells were 1.5 μmol/L and 1.8 μmol/L, respectively. When cells were exposed to irradiation and the maximum non-cytotoxic doses of tetrandrine, the survival fraction was decreased. DNA damage and γ-H2AX levels markedly increased. Moreover, tetrandrine abrogated the G2/M phase arrest caused by irradiation. Combined treatment with the maximum non-cytotoxic dose of tetrandrine and irradiation caused suppression of the phosphorylation of CDK1 and CDC25C and increase in the expression of cyclin B1. The study in vivo also showed that the maximum non-cytotoxic dose of tetrandrine could reduce tumor growth in xenograft tumor model. Our results suggest that the maximum non-cytotoxic dose of tetrandrine can enhance the radiosensitivity of CNE1 and CNE2 cells and that the underlying mechanism could be associated with abrogation of radiation-induced G2/M arrest via activation of the CDC25C/CDK1/Cyclin B1 pathway.     

Preparation and characterization of solid lipid nanoparticles loaded traditional Chinese medicine

Ultrasonication was employed to prepare solid lipid nanoparticles (SLN). The model traditional Chinese medicine, tetrandrine (TET), was incorporated into SLN. The TET–loaded SLN (TET–SLN) were spherical in the photograph of transmission electron microscope (TEM). The particle size measured by laser diffraction (LD) was found to be 157.3 ± 8.2 nm. Zeta potential analyzer suggested the zeta potential of TET–SLN was −29.36 ± 3.68 mV in distilled water. The entrapment efficiency (EE%) was determined with the sephadex gel chromatogram and high-performance liquid chromatogram (HPLC), and up to 90.59% of TET was incorporated. Stability evaluation showed relatively long-term stability with only slight particle growth (P > 0.05) after storage at room temperature for 4 weeks. Therefore, ultrasonication is demonstrated to be a simple, available and effective method to prepare high quality SLN loaded traditional Chinese medicine.     

Design,synthesis and biological activities of tetrandrine and fangchinoline derivatives as antitumer agents

The isolation and modification of natural products is always a very important resources to anti-tumor drugs. Therefore, a novel series of tetrandrine and fangchinoline derivatives were designed and synthesized, and their antiproliferative activities against HepG2, MCF-7 cells were evaluated and described. From the activity result obtained, high to very high activity in vitro has been found, one of the tested compounds (compound 5d) exhibited the most significant cytotoxic effects. Compound 5d increased 29.2, 7.37 times anti-proliferative activity for HepG2 cells and MCF-7 cells compared to sunitinib (IC₅₀ = 16.06 μM and 25.41 μM). Finally flow cytometry determined that compound 5d could indeed inhibit the proliferation of HepG2 cells via inducing apoptosis.     

柔红霉素在人敏感和抗三尖杉酯碱的HL－60细胞中分布和积聚变化

应用激光扫描共焦显微镜和流式细胞术,研究柔红霉素在人敏感和抗三尖杉酯碱的ＨＬ－６０细胞中分布和积聚变化。柔红霉素１０μｇ／ｍｌ处理细胞１小时,激光扫描共焦显微镜观察到：在敏感ＨＬ－６０细胞中,柔红霉素主要分布于细胞核中;而在抗性细胞中,主要分布于细胞一侧。逆转抗药性的药物维拉帕米不改变柔红霉素在抗性细胞中的核质分布。流式细胞术显示：三尖杉酯碱和蛋白激酶Ｃ激活剂佛波脂处理细胞,使柔红霉素在抗性细胞内积聚降低;而粉防己碱和维拉帕米处理细胞１小时,柔红霉素在抗性细胞内积聚明显增加,但维拉帕米处理２４小时,反而使积聚降低。结果表明：抗三尖杉酯碱的ＨＬ－６０细胞改变桑红霉素的胞内分布,降低细胞内的积聚是抗药性的机制之一。     

粉防已碱与红细胞膜ATPase相互作用的研究

粉防已碱是一种新的钙调蛋白拮抗剂,专一性抑制人红细胞膜上依赖CaM的Ca~(2+)-Mg~(2+)-ATPase。在较高浓度下,它也不同程度地抑制Ca~(2+)-Mg~(2+)-ATPase基本活性、Na~+-K~+-ATPase和Mg~(2+)-ATPase的活性。 除CaM外,不饱和脂肪酸和有限水解均导致膜Ca~(2+)-Mg~(2+)-ATPase的活化,所有这些活化作用被Tet在大约相同的浓度范围内抑制,表明Tet除与CaM结合外,也与膜Ca~(2+)-Mg~(2+)-ATPase结合。 Tet具有抗抵渗溶血的性能,反映了拮抗CaM与药物的膜稳定性间存在相关性。     

汉防己甲素滴眼液对高眼压模型大鼠的降眼压作用

目的比较观察汉防己甲素滴眼液与0.5%噻吗心安滴眼液对高眼压模型大鼠及正常大鼠降眼压的作用。方法正常SD大鼠共分4组：不同浓度的汉防己甲素滴眼液组（0.1%、0.2%、0.3%）及阳性对照组0.5%噻吗心安,药物滴右眼各一滴,阴性对照组生理盐水滴左眼、测量滴药前24h和滴药后1、3、6、24、48、72h的眼压。应用倍频532激光对SD大鼠右眼上巩膜静脉以及小梁网所在区域实施光凝术建立高眼压大鼠模型。高眼压模型鼠共分5组：不同浓度的汉防己甲素滴眼液0.05%、0.1%、0.2%、0.3%及阳性对照组0.5%噻吗心安,右眼即模型眼滴用药物,左眼作为空白对照。测量术前后的眼压。结果汉防己甲素滴眼液对大鼠正常眼压无降压作用（P〉0.05）。对高眼压大鼠用药后24h、72h、1周后,0.3%汉防己甲素滴眼液组降低眼压的幅度与0.5%噻吗心安滴眼液降低眼压的幅度相似（P〉0.05）;0.05%、0.1%、0.2%汉防己甲素滴眼液组也有明显的降压作用,但与0.5%噻吗心安滴眼液相比,降压幅度低于后者（P〈0.05）。结论0.05%、0.1%、0.2%、0.3%汉防己甲素滴眼液均有降低大鼠高眼压的作用,其中0.3%浓度的汉防己甲素滴眼液降眼压效果与0.5%的噻吗心安类似。汉防已甲素滴眼液作为一种治疗青光眼的药物有着良好应用前景。     

Targeting the Ca2+/Calmodulin-dependent protein kinase II by Tetrandrine in human liver cancer cells

Hepatocellular carcinoma (HCC) is the most prevalent malignancy in liver and a leading cause of cancer-related deaths. Despite the pressing need for treatment options, patients with HCC develop significant resistance and adverse side effects to current approved drugs that becomes a major barrier to effective treatment. A natural product Tetrandrine (TET) is a potential alternative treatment option for HCC, with demonstrated effectiveness and low toxicity. However, the mechanisms by which Tetrandrine inhibits HCC are unclear. In the current study, we identify Ca²+/calmodulin-dependent protein kinase II δ (CaMKIIδ) as a potential TET drug target through structural modeling. Screening of a panel of HCC cell lines reveal differential sensitivities toward TET treatment. Interestingly, IC₅₀ of TET inhibition of HCC cell proliferation is positively correlated with CaMKIIδ expression level in these distinct HCC cells. Furthermore, TET treatment resulted in a marked reduction of CaMKIIδ phosphorylation level, and knockdown of CaMKIIδ reduced the sensitivity of HCC cells to TET. Most importantly, CaMKIIδ protein levels in high-grade human HCC samples were significantly elevated as compared to normal liver tissues. Taken together, our studies demonstrate that the natural compound TET targets CaMKIIδ in HCC cells, and that CaMKIIδ level is a potential biomarker to identify HCC patient populations sensitive to Tetrandrine treatment.