Animals ; Cytological Techniques ; methods ; Cytophotometry ; instrumentation ; methods ; Humans ; Pharmacology ; methods ; trends ; Systems Biology ; methods ; Toxicology ; methods ; trends

OBJECTIVE: To study signal transduction pathways in cultured rat hepatocytes in the high nitric oxide (NO) environment of hepatitis. METHODS: NO levels were assessed by measurement of its stable oxidative products nitrite (NO2(-)) and nitrate (NO3(-)) using the Griess method with or without thiols (GSH or L-Cys). Rat hepatocytes were incubated with Sodium Nitroprusside (SNP) to produce a high NO environment and the intracellular cGMP and s-nitrosoglutathione (GSNO) in the culture media were measured using radioimmunoassay or with the MTT assay absorbed at 334nm respectively. RESULTS: After incubation of 1.543 mmol/L SNP for 30 minutes 0.63+/-0.06 mmol/L and at 25 minutes 0.98+/-0.11 mmol/L of NO was released in containing 25 mmol/L GSH and L-Cys condition. The levels of both cGMP and GSNO were significantly increased (compared with control P<0.05) in a dose related manner. CONCLUSION: Signal transduction of cultured rat hepatocytes in a high NO environment could be a cGMP-dependent as well as a non-cGMP-dependent pathway.

OBJECTIVE: To investigate the augmentation of microsomal glutathione S-transferase (mGST) preparation using simple organic compounds. METHODS: Rat liver microsomes were isolated using both the polyethyleneGlyco 6000 (PEG6000) and Ca(2+) precipitation methods. Next the mGST activity was measured after incubation with the alkylating agent N-ethylmaleimind (NEM). RESULTS: The baseline mGST activity of rat microsomes was 0.15 after PEG6000 exposure and 0.082 after Ca(2+) precipitation. After NEM treatment mGST activity increased to 1.797 (2.35X) (P<0.01) and 2.375 (4.127X) (P<0.01) respectively followed by purified washing. mGST activation was stimulated maximally by 5-10 mmol/L NEM and occurred rapidly with 1-2 min of co- incubation. CONCLUSION: For both the PEG6000 and Ca(2+) precipitation methods the mGST activity of rat microsomes can be significantly enhanced after exposure to NEM. This enhancement is more prominent with the Ca(2+) precipitation.

OBJECTIVE: To establish a hepatocyte immunotoxicity model for screening of liver protective medications. METHODS: Cytotoxicity was induced by coincubating BCG-pretreated rat hepatocytes in vivo and with 10 mg/L LPS in vitro. Biphenyldimethylesterate (DDB), malotilate(MLT), silybin(SB) and glycyrrhizin (GRZ) were coincubated along with LPS to prevent the hepatocyte injury and verify the applicability and reliability of the model. AST, LDH and nitric oxide (NO) were measured in both the serum and supernatant. The liver and spleen index were calculated and the liver histopathologic changes were examined microscopically. RESULTS: Supernatant AST, LDH and NO in the BCG combined LPS group were increased in comparison with the control group (P<0.01). This increase was attenuated by the addition of DDB, MLT, SB and GRZ (P<0.05). The serum AST, NO and liver and spleen index were also increased significantly compared with the control group (P<0.01). Microscopic exam revealed serious histopathologic changes in the BCG combined LPS group. Hepatoxicity with associated liver enzyme elevation but histopathologic changes were attenuated by DDB, MLT, SB and GRZ. CONCLUSION: BCG combined LPS-induced hepatocyte immunotoxicity in an in vitro rat model may be a useful technique to assess the effectiveness of liver protective medications.

OBJECTIVETo explore the estrogenic activity and its mechanism of ethanol extract from black soybean (BSE).

METHODThe modified MCF-7 cell proliferation assay was used to evaluate the estrogenic activity of BSE. And the possible mechanisms were addressed using RT-PCR measurements in which pure estrogen receptor antagonist ICI182,780 was employed as a tool.

RESULTThe estrogenic activity of BSE at various concentrations (1-1000 microg x mL(-1)), expressed as proliferative effect (PE) relative to that of solvent control, was examined. The results indicated that, at low concentration range (10-200 microg x mL(-1)), BSE was able to induce MCF-7 cell growth with a maximum at 100 microg x mL(-1). The results of RT-PCR showed that pS2 and PR mRNA could be significantly induced by BSE in MCF-7 cells, which was relative to the concentration of BSE. Moreover, the specific estrogen receptor antagonist, ICI182,780 could block these reactions.

CONCLUSIONEthanol extract of black soybean can stimulate the growth of MCF-7 cells and increase the expression of estrogen receptor-responsive gene, suggesting that the estrogenic effects of BSE are mediated by the estrogen receptor.

Breast Neoplasms ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Estradiol ; analogs & derivatives ; pharmacology ; Estrogen Receptor Modulators ; pharmacology ; Female ; Humans ; Plants, Medicinal ; chemistry ; RNA, Messenger ; biosynthesis ; genetics ; Receptors, Progesterone ; biosynthesis ; genetics ; Seeds ; chemistry ; Soybeans ; chemistry ; Trefoil Factor-1 ; Tumor Suppressor Proteins ; biosynthesis ; genetics

OBJECTIVETo investigate the estrogen-like activities of icariin (ICA), icaritin (ICT) and desmethylicaritin (DICT) and their structure/activity relationships.

METHODSICT was hydrolyzed from ICA by cellulase and then DICT was demethylated from ICT in boron tribromide and dichloromethane system. Estrogen-sensitive MCF-7 cells and T47D cells were co-incubated with different concentrations of test compounds for 6 and 9 d respectively, and the cell proliferation was measured by MTT.

RESULTSICT and DICT both markedly enhanced cell proliferation. Compared with estradiol (10.(-9) mol/L), the proliferative effects of 10.-6 mol/L ICT and DICT on MCF-7 cells were 90.0% and 94.0% (P<0.01), respectively, and those of T47D cells were 65.6% and 50.0%. (P<0.01). But this phenomenon was not observed with ICA. Cell proliferation induced by ICT and DICT was completely antagonized by 10.(-7 )mol/L pure estrogen receptor antagonist, ICI182,780.

CONCLUSIONICT and DICT possess estrogen-like activity of enhancing proliferation in MCF-7 and T47D cells. However, ICA appears to have no estrogenicity on MCF-7 and T47D cell lines in vitro.

Breast Neoplasms ; pathology ; Cell Division ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Flavonoids ; chemistry ; pharmacology ; Humans ; Phytoestrogens ; isolation & purification ; pharmacology ; Tumor Cells, Cultured

OBJECTIVETo investigate the gene expression of MAPEG in the cortex of concanavalin A (Con A)-induced mouse immune inflammatory model and the effect of cyclosporine A (Cs A).

METHODSMale Balb/c mouse immune inflammation model was developed by intravenous injection of Con A (20 mg/kg). Cs A (150 mg/kg) was intravenously infected prior to Con A administration. The MAPEG expressions were determined by RT-PCR.

RESULTmGST1, mGST3, LTC(4)S, FLAP and mPGES-1 were detected by RT-PCR but not mGST2. Eight hours after Con A treatment, mGST1 level was up-regulated to 1.2 approximately 1.5 folds of control with or without Cs A treatment. mGST3ìLTC(4)S, FLAP and mPGES-1 mRNA levels were not influenced by Con A administration.

CONCLUSIONImmune mechanism may be not involved in mGST1 up-regulation in this model and Con A does not alter arachidonic acid metabolism in cortex.

5-Lipoxygenase-Activating Proteins ; Animals ; Brain ; metabolism ; Carrier Proteins ; genetics ; metabolism ; Concanavalin A ; toxicity ; Cyclosporine ; pharmacology ; Eicosanoids ; metabolism ; Glutathione ; metabolism ; Glutathione Transferase ; genetics ; metabolism ; Intramolecular Oxidoreductases ; genetics ; metabolism ; Male ; Membrane Proteins ; genetics ; metabolism ; Mice ; Mice, Inbred BALB C ; Prostaglandin-E Synthases

Animals ; Cell Differentiation ; drug effects ; Cell Transplantation ; Cells, Cultured ; Disease Models, Animal ; Drug Evaluation, Preclinical ; Embryonic Stem Cells ; cytology ; Humans ; Regeneration ; drug effects

OBJECTIVETo observe the therapeutic efficacy of 131I-labeled granulocyte macrophage colony-stimulating factor (GM-SCF) in SCID mouse-acute myeloid leukemia model, and the relationship between dose and effect.

METHODSSCID-mouse acute myeloid leukemia model was established by injecting HL-60 cells through tail vein. GM-CSF was labeled with 131I by the chloramines-T method. SCID mice were randomly divided into 6 groups. Groups I, II and III treatment groups were given 9.25 x 10(5), 22.20 x 10(5) and 37.00 x 10(5) Bq of 131I-GM-CSF, respectively. Group IV was given 131I. Group V was given blending of 131I and GM-CSF. Group VI was control. Changes of HL-60 cells in blood and marrow, as well as white blood cells, red blood cells and platelets in blood were detected. Survival time of the SCID mice was calculated.

RESULTIt was observed that WBC, HL-60 cells in blood and marrow were less in treatment groups than that in control groups, especially in groups II, III. After 2 weeks of treatment, BPC of II, III groups increased remarkably (P < 0.01). Survival time of the SCID mice was prolonged in treatment groups (P < 0.01), especially in group III, the longest survival time of 60 days.

CONCLUSION131I-GM-CSF could increase leukemic SCID mice survival rate. The therapeutic efficacy of low dose and mediate dose of 131I-GM-CSF is dose-dependent. 131I-GM-CSF is an effective radiation immunity therapy for leukemic mice.

Animals ; Antineoplastic Agents ; therapeutic use ; Dose-Response Relationship, Drug ; Female ; Granulocyte-Macrophage Colony-Stimulating Factor ; therapeutic use ; HL-60 Cells ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; Mice ; Mice, SCID ; Xenograft Model Antitumor Assays