Improvement Effects of α-lipoic Acid on Glucose Metabolism Disorder of Insulin Resistant HepG 2 Cells / 中国药房

OBJECTIVE：To study the i mprovement effects of α-lipoic acid on glucose metabolism disorder of insulin resistant HepG2 cells. METHODS ：The effects of 25-1 000 µmol/L α-lipoic acid on survival rate of human hepatoma cell HepG2 were determined by MTT assay so as to determine the concentration of α-lipoic acid. Negative control group ，insulin resistance group （1× 10－7 mol/L insulin ），combination resistance group （30 µmol/L sodium arsenite+ 1×10－8 mol/L insulin ），α-lipoic acid low- concentration，medium-concentration and high-concentration groups were set up. HepG 2 cells were treated with α-lipoic acid for 12 h and then cultured with corresponding concentration of sodium arsenite or/and insulin for 24 h. The glucose oxidase method was used to detect the glucose consumption ，colorimetric method was used to detect hexokinase activity and pyruvate kinase activity ， and anthrone method was used to detect glycogen content. Western blot assay was used to detect the protein expression of GLUT 4， p-GSK3β and GSK3β as well as the ratio of p-Akt/Akt and p-GSK3β/GSK3β. RESULTS：25，50，100 µmol/L α-lipoic acid had no significant effect on the survival rates of HepG 2 cells（P＞0.05），and survival rates of H epG2 cells were higher than 96％，so they were used as the low ，medium and high concentration for follow-up study. Compared with negative control group ，glucose consumption，the activities of hexokinase and pyruvate kinase ，glycogen content ，protein expression of GLUT 4 and p-GSK 3β，the ratio of p-Akt/Akt and p-GSK 3β/GSK3β were decreased significantly in insulin resistance group and combined resistance group， while the protein expression of GSK 3β was increased significantly（P＜0.05）. Compared with combination resistance group ，the glucose consumption （except for α-lipoic acid low- concentration group ），the activities of h exokinase（except for α-lipoic acid low-concentration and medium-concentration groups ） andpyruvate kinase （except for α-lipoic acid low-concentration com and medium-concentration groups ）， glycogen contents ， protein expression of GLUT 4 （except for α-lipoic acid mail：bliang163@163.com low-concentration group ）and p-GSK3β，the ratio of p-Akt/ Akt（except for α-lipoic acid low-concentration and medium-concentration groups ）and p-GSK 3β/GSK3β（except for α-lipoic acid low-concentration groups ）were increased significantly in α-lipoic acid groups ，while protein expression of GSK 3β（except for α-lipoic acid low-concentration and medium-concentration groups ） was decreased significantly （P＜0.05）；glycogen content ， protein expression of GLUT 4 and the ratio of p-GSK 3β/GSK3β in α-lipoic acid high-concentration group as well as the protein expression of p-GSK 3β in α-lipoic acid medium-concentration and high-concentration groups were improved significantly （P＜0.05）. CONCLUSIONS：α-lipoic acid can improve the disorder of glucose metabolism in insulin resistant HepG 2 cells，the mechanism of which may be associated with the increase of glucose consumption ，the activities of glucose metabolism related enzymes and glycogen content ，and expression up-regulation of the phosphorylation levels of Akt and GSK 3β protein，the expression of GLUT 4 and p-GSK 3β proteins，down-regulation of the expression of GSK 3β protein.

Study on Synthesis and Anti-tumor Activity of 6 Kinds of Tectorigenin Mannich Base Derivatives / 中国药房

OBJECTIVE： To conduct structural modification of tectorigenin to search for new compounds with anti-tumor activity. METHODS： Tectorigenin was used as a lead compound， and then added into amine reagents as ethanolamine， methylamine， ethylamine， dimethylamine， diethylamine， n-propylamine and formaldehyde solution. Tectorigenin Mannich base derivatives were synthesized by mannich reaction with as the lead compound. The structures of the derivatives were identified according to IR， UV， MS and NMR data. Solubility of tectorigenin and its derivatives were investigated by solubility test method. MTT assay was used to investigate the inhibitory effects of tectorigenin and its derivatives on the proliferation of human colon cancer cell line HCT116， human lung cancer cell line A549 and human hepatoma cell line HepG2， and half inhibitory concentration （IC50） was calculated. The inhibition rate of tectorigenin and its derivatives （100 mg/kg） on H22 hepatoma-bearing mice in vivo was studied. RESULTS： Totally of 6 kinds of tectorigenin mannich base derivatives were synthesized， such as 8-（N-hydroxyethyl）-methyleneamino-5，7，4′-trihydroxy-6-methoxyisoflavone， 8-（N-methyl）-methyleneamino-5，7，4′-trihydroxy-6- methoxyisoflavone， 8-（N， N-diethyl）-methyleneamino-5，7，4′-trihydroxy-6-methoxyisoflavone， 8-（N， N-dimethyl）-methyleneamino- 5，7，4′-trihydroxy-6-methoxyisoflavone， 8-（N-ethyl）-methyleneamino-5，7，4′-trihydroxy-6-methoxyisoflavone， 8-（N-propyl）- methyleneamino-5，7，4′-trihydroxy-6-methoxyisoflavone （compounds 1-6 in turn）. Compared with tectorigenin， the water solubility of six derivatives was significantly improved， and the solubility was 5-20 times higher than that of tectorigenin. IC50 of compounds 1， 3 and 5 to HCT116 cells were （34.82±3.27）， （16.21±4.13）， （33.12±3.25） μmol/L， which were stronger than that of tectorigenin [（45.23±5.74） μmol/L]； IC50 of compounds 1， 3 and 5 to A549 cells were （37.05±5.74）， （26.88±4.52）， （30.13±6.23） μmol/L， which were stronger than that of tectorigenin [（53.24±6.34） μmol/L]； IC50 of compounds 1， 3 and 5 to HepG2 cells were （23.74±1.45）， （18.96±2.34）， （30.95±2.87） μmol/L， which were stronger than that of tectorigenin [（48.98±2.58） μmol/L]. Compounds 1， 3 and 5 showed higher inhibition rates （55.51％， 57.20％ and 49.15％） than tectorigenin （33.05％） on H22 hepatoma-bearing mice， respectively. The other three compounds had no obvious advantage over tectorigenin in anti-tumor activity. CONCLUSIONS： In this study， compounds 1， 3 and 5 of six tectorigenin mannich base derivatives synthesized in this study have stronger antitumor activity than tectorigenin.

Apoptosis of Human Hepatoma Cell Line SMMC-7721 Induced by Dihydroartemisinin and Its Possible Mechanism / 中国药学杂志

OBJECTIVE: To investigate the apoptosis effect of human hepatocellular carcinoma cell line SMMC-7721 induced by dihydroartemisinin in vitro and the possible mechanism. METHODS: After treatment with 25, 50, 100, 200, and 400 μmol•L-1 dihydroartemisinin for 24 h. The proliferation inhibitory effect of dihydroartemisinin on SMMC-7721 cell was detected by MTT assay. Cell cycle and apoptosis were detected by flow cytometry. The change of apoptotic morphology was detected by confocal laser scanning microscopy. Rho 123 staining method was used to detect the changes of mitochondrial membrane potential. Western blot was used to detect expression of Bcl-2, Bax, Cleaved Caspase-3, Cleaved Caspase-9 and Cyto C. RESULTS: MTT results showed that 25-400 μmol•L -1 dihydroartemisinin can inhibit the proliferation of SMMC-7721 cells obviously. The cell cycle detection results of flow cytometry showed that dihydroartemisinin could block SMMC-7721 cell cycle in G2/M phase. The results of Hochest 333258 staining showed that the nuclei were heterogeneous, condensed and fragmented in the DHA treatment group. The cell apoptosis detection results of flow cytometry showed that the apoptosis rate of dihydroartemisinin treated groups were increased obviously (P < 0.01). The results of Rho 123 staining showed that the mitochondrial membrane potential was decreased significantly (P < 0.01). Western blot results showed that the expression of Bcl-2 was down-regulated, expression of Bax was up-regulated, the ration of Bax /Bcl-2 was increased and the expression of Cleaved Caspase-3, Cleaved Caspase-9 and Cyto C were up-regulated. CONCLUSION: Dihydroartemisinin can induce apoptosis of SMMC-7721 cells, on the mechanism of apoptosis may be related to mitochondrial pathway.

Indução do sistema citocromo P450 em linhagens de hepatoma humano para utilização como modelo in vitro no desenvolvimento de fármacos / Induction of cytochrome P450 system in human hepatoma cell lines for using as in vitro model in drug development

Na etapa inicial do desenvolvimento de novos fármacos, a avaliação do metabolismo e da toxicidade é fundamental para definir seu potencial emprego como candidato a fármaco. Nestes estudos, diversos modelos in vitro são empregados, dentre eles linhagens de hepatoma humano. Entretanto, uma grande limitação ao uso deste modelo in vitro é a baixa expressão das enzimas do sistema citocromo P450. O carotenóide bixina, componente majoritário do anato (urucum), apresentou em estudos in vivo, a capacidade de induzir algumas isoformas do sistema citocromo P450, com a vantagem de apresentar baixa toxicidade. Neste trabalho, a fração lipossolúvel do anato (bixina) e hidrossolúvel (norbixina) foram avaliadas como indutores do sistema citocromo P450 em linhagens de hepatoma humano. Ensaios de MTT, empregando as linhagens HepG2, C3A e SK-HEP-1 indicaram que bixina e norbixina em concentrações abaixo de 0,22 mM são seguras quanto à citotoxicidade. A expressão dos genes CYP 1A1, 1A2, 2C9, 2B6, 2E1 e 3A4 foi avaliada, através de ensaios de RT-PCR em tempo real, em linhagens de hepatoma humano submetidas a tratamento com os compostos bixina e norbixina. Os resultados mostraram que células HepG2 e C3A tratadas com bixina nas concentrações de 0,05 e 0,1 mM, por períodos de 24 e 48 horas, apresentaram aumento de expressão da CYP 1A1 e CYP 1A2. Porém, a exposição de células HepG2 e C3A ao composto norbixina não resultou em aumento de expressão das isoformas avaliadas neste estudo. Os resultados deste trabalho indicaram o potencial emprego de bixina como agente indutor das CYPs 1A1 e 1A2, em linhagens de hepatoma humano utilizadas como modelo in vitro, para estudo de compostos cuja metabolização envolva uma destas vias, entretanto, estudos adicionais são fundamentais, a fim de avaliar a ação deste composto sobre outras isoformas do sistema citocromo P-450, bem como outros sistemas enzimáticos.

In the early development stage of the new drugs, the pharmacological and toxicological properties are critical to define the potential use of the candidate drug. During this stage, several in vitro models systems are employed, including human hepatoma cell lines. However, the main limitation of the use of cell lines as in vitro model is the low expression level of cytochrome P450 enzymes. A carotenoid knowed as bixin, the main pigment in the annatto (urucum), it has been reported to induce some isoforms of cytochrome P450 in rats, with the advantage of its low toxicity. In this work, the oil-soluble (bixin) and aqueous soluble extracts (norbixin) were evaluated as inducers of the cytochrome P450 system in human hepatoma cell lines (HepG2, C3A, SK-HEP-1). The results of MTT assays showed that bixin concentrations below 0.22 mM were not cytotoxic in HepG2, C3A and SK-HEP-1 cell lines. Expression changes in CYP 1A1, 1A2, 2C9, 2B6, 2E1 and 3A4 were evaluated, by real time RT-PCR and the results showed that the exposition to 0,05 mM and 0,1 mM bixin, for 24 and 48 hours of treatment, lead to an increase in CYP 1A1 and CYP 1A2 expression level. By contrast, the cytochrome P450 isoforms were not affected by the exposition to norbixin. In conclusion, this work indicated the potential use of bixin induced hepatoma cell lines as in vitro model for studies of biotransformation and toxicity of drugs involving CYP 1A, however, further studies are necessary to evaluate the effect of bixin on the other cytochrome P450 isoforms as well as other enzymatic systems.

Inhibition of proliferation of 5-FU combined with thermotherapy in human hepatoma cell line / 中国综合临床

Objective To investigate the inhibition rate of cell proliferation, cell apoptosis rate and their effects on the cell cycle proceeding of the SSMC7721 cell line when 5-FU combined with thermotherapy is induced into the cells, and then provide theoretical bases to the combined therapy of hepatocellular carcinoma. Methods The inhibition rate of cell proliferation was detected by the MTT under different conditions, the cell cycle proceeding and the cell apoptosis rate was detected by flow cytometry and the subcellular structure was detected by the electronmicroscope. Results The cell inhibition rate of the thermotherapy group, 5-FU group and the combinedgroup were 18.4% ,28. 3% and 52. 7% ,respectively. The inhibition rates in the latter two groups were significantly different to the thermotherapy group. The results of flow cytometry showed that the cell numbers increased in G1 stage decreased in S stage,and increased in G2/M stage;the cell apoptosis rate increased. There was significant difference between different groups(P ＜ 0.01 or P ＜0.05). The results of the electronmicroscop showed that the nuclear chromatins agglutinated in the borderline and the mitochondriums became swelled. Conclusions The 5-FU combined with thermotherapy could significantly improve the inhibition rate of cell proliferation, inhibit the cell cycle proceeding from G1 stage to S stage, and induce cells apoptosis and change the subcellular structures in the SSMC7721 cell line.

The Persistent Secretion of TNF-? by60Co Irradiated TNF Gene Modified Human Hepatoma Cell / 中国肿瘤生物治疗杂志

?-tumor necrosis factor can enhance tumor cells autolysis and the expression of HLA antigenes. So we infected Human Hepatoma Cell Line (HHCL)with recombinant retroviral vector containing an insert of human tumor necrosis factor-? cDNA. The transduced tumor cells were isolated by G418 selection. After being irradiated by different doses of 60Co, their expression of TNF in 24 hours were tested. Observations of the relationship between the doses of irradiation and the expression levels of TNF were done. We also preserved the irradiated HHCL-TNF cells into liquid nitrogen, after recovering, tested their expressions of TNF again. This paper shows that: (l)following irradiation by 60Co, the production of ?-TNF persisted for about four weeks, and there is no difference among the different irradiated doses(40G~100G); (2)After being irradiated and kept into liquid nitrogen, the recovering HHCL-TNF cells constitutively secrete ?-TNF for about three weeks.These findings provide a logical basis for designing protocols for active immunotherapy in humans.

Preliminary studies on the antitumor activities of D-glucosamine and its derivatives / 中国海洋药物

Objective The growth inhibitory effects of GlcNH_2?HCl,GlcNH_2 and NAG on human hepatoma SMMC-7721 cells in vitro was investigated.The antitumor activity of GlcNH_2?HCl against Sarcoma_(180) in KM mice was also investigated.Methods The cell viability in vitro was examined with MTT assay.DNA isolation and cell-cycle analyses were also performed.GlcNH_2?HCl was ig administered to Sarcoma_(180) KM mice.The inhibition rates,spleen and thymus index were calculated.Results GlcNH_2?HCl and GlcNH_2 resulted in a concentration-dependent reduction in hepatoma cell growth.The inhibition rates against SMMC-7721 cell of GlcNH_2?HCl and GlcNH_2 at concentration of 500?g?mL~(-1) were(50.24)% and 52.19%.As to the concentration of 1000?g?mL~(1), the rates were(82.21%) and 83.20%.This effect was accompanied by a marked increase in the proportion of S phase cells.Compared with the control,there was no significant difference among various concentrations of NAG,GlcNH_(2)?HCl exhibited inhibitiory effect against Sarcoma_(180) in mice at the dosage of 125～500 mg?kg~(-1),and the inhibition rate was about 27.84%～34.02%.The optimal inhibitory effect was 250 mg?kg~(-1).GlcNH_2?HCl could enhance the weights of thymus and spleen.In addition,it could promote lymphocyte transformation.Conclusion It is therefore postulated that the antitumor effect of GlcNH_2?HCl is probably host-mediated and cytocidal.

SYNERGISTIC EFFECT OF HYPERTHERMIA ON PHOTOCARCINORIN PHOTODYNAMlC THERAPY / 第二军医大学学报

In this paper, we describe a synergistic effect of hyperthermia on photocarcino-rin photodynamic therapy. The results suggest that the synergistic action of hyperthermia and photodynamic reaction was markedy better than that of hyperthermia alone plus photocarcinorin alone. with hyperthermia treatment (42℃, 30 min) alone, the fraction of cells inactivated was 7%, while with photodynamic effect alone(1J/cm2) that was 30% (?5%).when the same dosage of irradiation was applied after a rise in temperature, the fraction of cells inactivated increased to 80% (?5%) and when temperature was raised to the same amount after irradiation the fraction of cells inactivated increased to 92%. It can be seen that hyperthermia enhances, the response of tumor cells to photocarcinorin photodynamic effect in a synergistic way.