Effects of tachyplesin on the regulation of cell cycle in human hepatocarcinoma SMMC-7721 cells

AIM: To investigate the effects of tachyplesin on the cell cycle regulation in human hepatcarcinoma cells. METHODS: Effects of tachyplesin on the cell cycle in human hepatocarcinoma SMMC-7721 cells were assayed with flow cytometry. The protein levels of p53, p16, cyclin D1 and CDK4 were assayed by immunocytochemistry. The mRNA levels of p21(WAF1/CIP1) and c-myc genes were examined with in situ hybridization assay. RESULTS: After tachyplesin treatment, the cell cycle arrested at G(0)/G(1) phase, the protein levels of mutant p53, cyclin D1 and CDK4 and the mRNA level of c-myc gene a were decreased, whereas the levels of p16 protein and p21(WAF1/CIP1) mRNA increased. CONCLUSION: Tachyplesin might arrest the cell at G(0)/G(1) phase by upregulating the levels of p16 protein and p21(WAF1/CIP1) mRNA and downregulating the levels of mutant p53, cyclin D1 and CDK4 proteins and c-myc mRNA, and induce the differentiation of human hepatocacinoma cells

Effects of tachyplesin on proliferation and differentiation of human hepatocellular carcinoma SMMC-7721 cells

AIM: To investigate the antitumor activities of tachyplesin on human hepatocellular carcinoma (HCC) cells. METHODS: Tachyplesin, isolated from acid extracts of Chinese horseshoe crab ( Tachypleus tridentatus) hemocytes, was used to treat the human HCC cell line SMMC-7721. Effects of tachyplesin on the proliferation of SMMC-7721 cells were measured with trypan blue dye exclusion test and HE staining. The morphology and ultrastructure of the cells were examined by light microscopy and transmission electron microscopy, respectively. The activities of gamma-glutamyltransferase (gamma-GT) and tyrosine aminotransferase (TAT) were assayed with biochemical methods. The levels of alpha fetoprotein (alpha-FP), proliferating cell nuclear antigen (PCNA), p21(WAF1/CIP1) and c-myc were examined by immunocytochemistry. RESULTS: After treatment with tachyplesin 3.0 mg/L, the proliferation of SMMC-7721 cells was inhibited significantly, with the cell growth inhibitory rate amounted to 55.57% and the maximum cell mitotic index declined by 43.68%. The morphology and ultrastructure underwent restorational alteration. The activity of gamma-GT declined while TAT activity increased obviously, and the levels of alpha-FP and PCNA decreased. Moreover, the expression of p21(WAF1/CIP1) protein was up-regulated and that of c-myc protein was down-regulated. CONCLUSION: Tachyplesin could effectively inhibit the proliferation of hepatocarcinoma cells, reverse the malignant morphological and ultrastructural characteristics, alter the levels of enzymes and antigens, regulate the expression of differentiation-associated oncogene and tumor suppressor gene, and induce hepatocarcinama cell differentiation

Theoretical Study on Intramolecular Proton Transfer Reaction in 2-(2-Mercaptophenyl)benzoxazole

在b3lyP/6-31g(d,P)水平上研究了2-(2-巯苯基)苯并噁唑气态中五种异构体(E1,E2,E3,E4和k)在气态中的稳定性及其在基态下的质子转移,同时结合极化连续介质模型(PCM)研究了水、二甲亚砜、乙腈、乙醇、苯胺和环己烷等对2-(2-巯苯基)苯并噁唑溶剂化作用的影响.研究结果表明,醇式异构体E1为2-(2-巯苯基)苯并噁唑的优势构型;在E1向k(酮式异构体)转变过程中,存在一个较小的能垒;当考虑零点振动能(zPVE)后,逆向能垒消失.在溶液中,随着溶剂极性的增强,醇式异构体E1与k之间的反应平衡向k方向移动,在非极性溶剂环己烷中,E1为优势构型,而在强极性水溶液中,k为优势构型。The tautomers(E1,E2,E3,E4,and K) and the ground state intramolecular proton transfer reaction of 2-(2-mercaptophenyl)benzoxazole were studied at the B3LYP/6-31G(d,p) level.The effect of solvent(water,dimethylsulfoxide,acetonitrile,ethanol,aniline,and cyclohexane) was studied at the B3LYP/6-31G(d,p) level,using the polarizable continuum model.The results of density functional calculations indicate that the enol form E1 is the most stable tautomer at the ground state.In these solvents there is an equilibrium for 2-(2-mercaptophenyl)benzoxazole in the ground state between E1 and K,and the equilibrium shifts toward the tautomer K as the polarity of the solvent increases.E1 is the preferential conformation in cyclohexane,but K is the more stable tautomer in water.国家自然科学基金(Nos.20772027;20803020);973子课题(No.2003CB716005);中国博士后科学基金(No.20070410805)资助项

NMR and Theoretical Study on Interactions between Diperoxovanadate Complex and Substituted Pyridines

为探讨有机配体上取代基团对反应平衡的影响,在模拟生理条件下(0.15mol/L NaCl溶液),应用多核(1H,13C和51V)多维(DOSY)以及变温NMR技术研究双过氧钒配合物[OV(O2)2(D2O)]-/[OV(O2)2(HOD)]-(简写为bpV)与取代吡啶的相互作用.bpV与有机配体的反应性从强到弱的顺序为:皮考林酸根>异烟酸根>异烟酸甲酯>皮考林甲酯,这说明吡啶环上同一位置上的不同取代基团和同一取代基团在不同位置上都影响反应平衡,竞争配位导致一系列新的6配位(配体为异烟酸根和异烟酸甲酯)或7配位(配体为皮考林酸根和皮考林甲酯)的过氧钒物种[OV(O2)2L]n-(L=取代吡啶,n=1或2)生成,密度泛函计算结果较合理地解释了实验结果,并表明溶剂化在反应中起重要作用.To understand the substitution group effects of organic ligands on the reaction equilibrium,the interactions between diperoxovanadate complex [OV(O2)2(D2O)]-/[OV(O2)2(HOD)]-(abbr. bpV) and a series of substituted pyridines were explored using multinuclear(1H,13C,and 51V) magnetic resonance,DOSY,and variable temperature NMR in 0.15 mol/L NaCl ionic medium for mimicking the physiological condition. The reactivity order among the substituted pyridines and bpV is picolinate>isonicotinate> methyl isonicotinate>methyl picolinate. The competitive coordination results in the formation of a series of new six-coordinated(isonicotinate and methyl isonicotinate) or seven-coordinated(picolinate and methyl picolinate) peroxovanadate species [OV(O2)2L]n-(L=substituted pyridines,n=1 or 2). Both the different substitution groups at the same position and the same groups at the different substitution position affect these reactions. The results of density functional calculations provide someway a reasonable explanation for the relative reactivity of the substituted pyridines. Solvation effects play an important role in these reactions.国家自然科学基金(Nos.20772027,20803020);; 973子课题(No.2003CB716005);; 湖南省自然科学基金(No.06JJ30004);; 中国博士后科学基金(No.20070410805);; 湖南省教育厅青年项目(No.06B028);; 固体表面物理化学国家重点实验室资助项目;; 湖南科技大学博士基金(No.E-55107)资助项目

NMR Studies on Interactions between Diperoxovanadate and 1-Ethyl-1H-Imidazole

为探讨过氧钒配合物中有机配体对反应平衡的影响,在模拟生理条件下(0.15MOl·l-1nACl溶液),应用多核(1H、13C和51V)多维(COSy和HSQC)核磁共振(nMr)以及变温技术等谱学方法研究双过氧钒配合物[OV(O2)2l]-(l=d2O或HOd,与之配位的过氧钒物种简写为bPV)和[OV(O2)2ll′]n{-n=1-2,ll′=3-羟基-皮考啉酸根(3-OH-PIC),2-(2′-吡啶)-咪唑(Py-IM),1,10-邻菲啰啉(PHEn),与它们配位的含钒物种分别简写为bPV(3-OH-PIC)、bPV(Py-IM)和bPV(PHEn)}与n-乙基咪唑(n-ET-IM)的相互作用.实验结果表明,n-ET-IM与4种双过氧钒配合物反应性从强到弱的顺序为bPV>bPV(3-OH-PIC)>bPV(Py-IM)>bPV(PHEn).研究表明,金属中心上配体的配位能力、空间位阻和分子量等因素都对反应平衡产生较大的影响,同时竞争配位的结果导致新的6配位过氧物种[OV(O2)2(n-ET-IM)]-的生成.利用上述谱学方法有助于揭示此类相互作用体系的反应过程和配位方式.To understand the effects of organic ligands on the reaction equilibrium, interactions between a series of diperoxovanadate complexes [OV(O2)2L]- (L=D2O or HOD, the corresponding peroxovanadate species (bpV)) and [OV (O2)2LL′]n-{n=1-2; LL′ =3-hydroxyl-picolinate (3-OH-pic), 2-(2′-pyridine)-imidazole (py-im), 1,10-phenanthroline (phen), the corresponding peroxovanadate species bpV(3-OH-pic), bpV(py-im), and bpV(phen)}and 1-ethyl-1H-imidazole (N- Et-im) in solution were explored using multinuclear (1H, 13C, and 51V) magnetic resonance, COSY (correlated spectroscopy), HSQC (heteronuclear single quantum coherence) and variable temperature nuclear magnetic responance (NMR) using 0.15 mol·L-1 NaCl ionic medium to mimic physiological conditions.Experimental results indicated that the reactivity of these four complexes with 1-ethyl-1H-imidazole decreased as follows: bpV>bpV(3-OH-pic)>bpV(py-im)> bpV(phen).The coordinating ability, the steric effect, and the molecular weight of these organic ligands affected the reaction equilibrium.A new six-coordinated peroxovanadate species [OV(O2)2(N-Et-im)]- was formed because of competitive coordination.国家自然科学基金(20772027;20803020);中国博士后科学基金(20070410805);卫生部科学研究基金-福建省卫生教育联合攻关计划(WKJ2008-2-036);厦门市重大疾病攻关研究基金(3502Z20051027)资助项目---

NMR studies on interactions between diperoxovanadate complexes and 1-methylimidazole

To understand the effects of organic ligands of the diperoxovanadate complexes on the reaction equilibrium, the interactions between a series of diperoxovanadate complexes [OV(O-2)(2)LL '](n-) [n=1 similar to 3; LL '=oxalate, abbr. oxa; picolinate, abbr. pic; 2,2 '-bipyridine, abbr. bipy; and 1,10-phenanthroline, abbr. phen. The corresponding peroxovanadate species abbreviate bpV(oxa), bpV(pic), bpV(bipy), and bpV(phen)] and I-methylimidazole (abbr. N-Me-Im) in solution were explored using multinuclear (H-1, C-13, and V-51) magnetic resonance, COSY, and variable temperature NMR in 0.15 mol/L NaCl ionic medium for mimicking the physiological conditions. The experimental results indicated the activity order of these four complexes with I-methylimidazole as follows: bpV(oxa)> bpV(pic)> bpV(bipy)> bpV(phen). Both the coordinating capability and the steric effect of the organic ligands affect the reaction equilibrium. At the same time, a new six-coordinated peroxovanadate species [OV(O-2)(2)(N-Me-Im)](-) is formed due to the competitive coordination

第十八届美国理论与应用力学大会总结

1会议概况2018年6月5—9日,第18届美国理论与应用力学大会(18th U.S. National Congress of Theoretical and Applied Mechanics, USNCTAM2018)在美国芝加哥召开.本次大会由美国力学国家委员会和中国力学学会联合主办,旨在探讨和交流近四年世界范围内在理论和应用力学领域的基础研究、创新技术的最新进展,吸引了来自世界各地的近千名专家学

NMR Studies on Interactions between Diperoxovanadate and 1-Ethyl-1H-Imidazole

To understand the effects of organic ligands on the reaction equilibrium, interactions between a series of diperoxovanadate complexes [OV(O-2)(2)L](-) (L=D2O or HOD, the corresponding peroxovanadate species (bpV)) and [OV (O-2)(2)LL'](n-) {n=1-2; LL' =3-hydroxyl-picolinate (3-OH-pic), 2-(2'-pyridine)-imidazole (py-im), 1,10-phenanthroline (phen), the corresponding peroxovanadate species bpV(3-OH-pic), bpV(py-im), and bpV(phen)} and 1-ethyl-1H-imidazole (N-Et-im) in solution were explored using multinuclear (H-1, C-13, and V-51) magnetic resonance, COSY (con-elated spectroscopy), HSQC (heteronuclear single quantum coherence) and variable temperature nuclear magnetic responance (NMR) using 0.15 mol.L-1 NaCl ionic medium to mimic physiological conditions. Experimental results indicated that the reactivity of these four complexes with 1-ethyl-1H-imidazole decreased as follows: bpV > bpV(3-OH-pic)> bpV(py-im)> bpV(phen). The coordinating ability, the steric effect, and the molecular weight of these organic ligands affected the reaction equilibrium. A new six-coordinated peroxovanadate species [OV(O-2)(2)(N-Et-im)](-) was formed because of competitive coordination.National Natural Science Foundation of China [20772027, 20803020]; China Postdoctoral Science Foundation [20070410805]; Science Research Foundation of Ministry of Health & United Fujian Provincial Health ; Education Project for Tackling the Key Research [WKJ2008-2-036]; Health and Science and Technology of Xiamen, China [3502Z20051027

EFFECTS OF HMBA ON THE EXPRESSION OF CELL-CYCLE-ASSOCIATED GENES IN HUMAN HEPATOCARCINOMA SMMC-7721 CELLS

本文研究HMBA对人肝癌SMMC-7721细胞周期G_0/G_1期阻滞相关基因表达的影响。免疫细胞化学和核酸原位杂交检测结果显示,HMBA可明显上调p21~(WAFl/CIPl)、p16蛋白表达并增强p21~(WAFl/CIPl)基因转录,同时对CDK4、Cyclin D1蛋白表达以及c-myc基因转录均具有明显的下调作用。结果表明,HMBA可通过增强p21~(WAFl/CIPl)、p16基因表达而抑制Cyclin D1-CDK4活性,最终导致细胞进入S期所需的c-myc等基因转录活性下降,从而将细胞周期阻滞于G_0/G_1期,诱导人肝癌细胞分化。In this study, the effects of HMBA on the expression of G0/G1 phase arrest-associated genes in human hepatocarcinoma SMMC-7721 cells were investigated. Immunocytochemistry and in situ hybridization assay revealed that the levels of P21WAF1/CIP1 and p16 proteins and the level of P21WAF1/CIP1 mRNA were increased while the levels of CDK4 and Cyclin Dl proteins and c-myc mRNA were decreased in the cells treated with HMBA. These results showed that HMBA could up-regulate the expression of p21WAF1/CIP1 and p16 genes, down-regulate the activity of Cyclin D1-CDK4 and the transcription of c-myc gene which were necessary for cells entering into S phase, and so arrest the cells in G0/G1 phase, and induce the differentiation of human hepatocarcinoma SMMC-7721 cells.国家自然科学基金(No.30170724);; 教育部高等学校骨干教师基