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Objective To explore the effect of SFI in radiation-induced mice brain injury after 20 Gy cranial radiation.Methods The mice were divided into three groups:(1) control group,(2) RT-only group:the whole brain was irradiated with a dose of 20 Gy,(3) RT and SFI group:SFI at 20 ml/kg/d from 4 weeks after 20 Gy cranial radiation theraty(CRT).Results Morris water maze test showed that the latency of the irradiated group was longer than control group and SFI improved the cognitive function of mice (t =6.34,6.70,P ＜0.05).The expression of TNF-α reached to the highest level at 3 h after irradiation,and then it decreased but got the second higher level again at 4 weeks after irradiation.The expression of IL-1 β reached to the highest level at 72 h after irradiation and decreased until 4 weeks after irradiation.SFI decreased both expressions of TNF-α (t =11.34,9.70,6.07,P ＜ 0.05) and IL-1 β (t =12.27,5.70,7.52,P ＜ 0.05).Immune florescence staining showed that SFI reduced the number of activated microglia (t =12.35,8.64,7.82,P ＜ 0.05)and inhibited the translocation of p65 of microglia after irradiation.Conclusions Findings suggest that SFI may decrease microglial activation and suppress the expression of TNF-α and IL-1β by inhibiting the translocation of NF-κB p65 and then attenuate irradiation-induced brain injury.
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This study investigated the influence of silencing TRAF6 with shRNA on lipopolysaccharide (LPS)/toll-like receptor (TLR)-4 signaling pathway in vitro. Four plasmids (pGCsi-TRAF6-shRNA1, 2, 3, 4) containing different shRNA sequences were designed and synthesized. The proliferation of RAW264.7 cells after transfected with these plasmids was measured by MTT assay. Inflammatory cellular models were established by LPS stimulation. Levels of TNF-alpha, IL-1beta and TGF-beta1 in the supernatants, mRNA expressions of TRAF6, IL-6 and COX-2, protein expression of TRAF6 and translocation of NF-kappaB were assayed by ELISA, real-time quantitative PCR and Western blotting, respectively. The results showed that the TRAF6 gene knockdown by RNAi hardly inhibited the proliferation of RAW264.7 cells within 72 h. The mRNA and protein expression of TRAF6 was lower in the TRAF6-shRNA1, 2 groups than in the TRAF6-shRNA3, 4 groups. Therefore, pGCsi-TRAF6-shRNA1, 2 were selected for the subsequent experiments. Our results still showed that pGCsi-TRAF6-shRNA1, 2 could significantly reduce the production of pro-inflammatory cytokines and mediators including TNF-alpha, IL-1beta, IL-6 and COX-2, and inhibit NF-kappaB nuclear translocation. Moreover, pGCsi-TRAF6-shRNA1, 2 could suppress the release of TGF-beta1 at the protein level. It was concluded that the recombinant plasmid pTRAF6-shRNA can, to some extent, inhibit inflammatory response stimulated by LPS at the initial phase. TRAF6 may become the potential therapeutic target of many inflammation-related diseases.
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Objective To explore the inhibitory effects of Tanshinone Ⅱ A on the radiationinduced microglia activation and the possible mechanism.Methods Microglia cells BV-2 were irradiated with 2,4,8,16,and 32 Gy doses or sham-irradiated in presence or absence of 1.0 μg/ml Tanshinone Ⅱ A for 12 h,respectively.The effects of Tanshinone Ⅱ A on radiation-induced pro-inflammatory cytokines were evaluated using real-time PCR.The expression level of NF-κB p65 in cytoplasm and nucleus was measured by using Western blot.Immunofluorescence staining and confocal microscopy analysis were applied to detect the expression of γ-H2AX and p65 post-irradiation.Results The microglia cells were activated at 16,32 Gy post-irradiation.Radiation-induced release of the pro-inflammatory cytokines in BV-2 cells was detectable after irradiation.Tanshinone Ⅱ A decreased radiation-induced release of proinflammatory cytokines(t=5.56,P ＜ 0.05).Furthermore,western blotting showed that Tanshinone Ⅱ A could attenuate the nuclear translocation of NF-κB p65 submit post-irradiation.Immunofluorescence staining showed that γ-H2AX foci formation while p65 translocation into nucleus post-irradiation.Conclusions Tanshinone Ⅱ A exerts anti-inflammatory properties by suppressing the transcription of proinflammatory cytokine genes that might be associated with NF-κB signaling pathway.It is postulated that irradiation causes immediate cellular reaction and DSB triggers the molecular response which leads to NFκB pathway activation.
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Objective To explore the inhibitory effects of Corilagin on the production of proinflammatory cytokines in microglia induced by radiation. Methods The cytotoxicity of Corilagin was measured by MTT assay. Microglia BV-2 cells were irradiated 0 or 32 Gy after pretreated with Corilagin for 12 hours. Realtime-PCR was used to detect the mRNA levels of inflammatory cytokines, such as IL-1β,TNF-α on several time-points. The content of nitric oxide (NO) was determined with nitrate reductase method. The translocation of NF-κB was measured by Western blot and immunocytochemical stain.Confocal microscopy was used to observe the expression of Iba-1 and Nemo. Results No cytotoxicity was detected on BV-2 cells with 1-10 μg/ml Corilagin. Iba-1 expression in microglia cells was activated by irradiation, the expression levels of inflammatory cytokines, such as IL-1β, TNF-α and NO were also elevated. Whereas, the production of IL-1 β, TNF-α in activated microglia cells was significantly inhibited with 5 μg/mL corilagin ( tIL-1β = 6. 341, tTNF-α = 3.41 1, tNO = 3. 134, P ＜ 0. 05 ). Corilagin significantly inhibited the expression of Nemo and the translocation of NF-κB p65. Conclusion Corilagin could inhibit the activation of irradiated microglia cells and down-regulate the expression of inflammatory cytokines, via inhibition of the NF-κB signaling pathway.
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In this study, the anti-HBV effects of tea polyphenols (TP) were examined. After cells were exposed to TP for 3, 6, 9 days, amounts of HBsAg, HBeAg and HBV-DNA released into the supernatant of the cultured HepG2 2.2.15 cells were detected. TP, to some extent, inhibited the secretion of HBsAg and strongly suppressed the secretion of HBeAg in a dose-dependent (P<0.01) and time-dependent manner, with 50% maximal inhibitory concentration (IC50) value being 7.34 microg/mL on the 9th day, but the time-dependence was not significant (P=0.051). Expression of HBV-DNA in the supernatant of the cell culture also was significantly decreased in a dose-dependent fashion (P<0.01). The IC50 of TP in inhibiting HBV DNA was 2.54 microg/mL. It concluded that TP possessed potential anti-HBV effects and may be used as a treatment alternative for HBV infection.
Subject(s)
Antiviral Agents/pharmacology , DNA, Viral/analysis , Dose-Response Relationship, Drug , Flavonoids/pharmacology , Hep G2 Cells , Hepatitis B Surface Antigens/analysis , Hepatitis B e Antigens/analysis , Hepatitis B virus/drug effects , Inhibitory Concentration 50 , Phenols/pharmacology , Tea/chemistryABSTRACT
AIM:We examined the efficacy ofanti-L3T4 McAb in the T cell signaling pathway in treating ex-Derimental antoimmune cardiomyopathy in BALB/c mice,as a model of the autoimmune mechanism involved in human di-latedardiomyopathy(DCM).METHODS:ADP/ATP carrier peptides were used to induce autoimmune cardiomyopathy in BALB/c mice.Afier 3 months.anti-L3T4 McAb WaS administered to deplete CD4+ T ceHs in the mice.Real-time PCR were used to detect the expression of intracellular signaling molecules(p561ck,p59fyn and Zap-70)and cytokine production(IFN-r,IL-2 and IL-4)in T cells.The expression of CIM5 was determined by immunohistochemistry a-nalysis.RESULTS:Reduced expression of p561ck,p59fyn and Zap-70 and the reduced cytokine production of IFN-r, IL-2 and IL-4 in T cells of anti-IJ3T4-treated DCM mice were found.Also,the expression of CD45 in spleen T cells was significantiv decreased in the anti-L3T4-treated group.In contrast,immunization with irrelevant Ab did not protect the mice.the expression of T cell signaling molecules,CD45,and cytokine were not inhibited.CONCLUSION:Thesestudies provide direct evidenee that anti-L3T4 McAb can be all effective immunomodulator to T cell signal molecules and 8ubsequent cytokine production events in ADP/ATP carrier-induced DCM in BALB/c mice.
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Objective To investigate the effect of recombinant plasmid pshRNA-DNMT3b on expression of DNMT3b mRNA and protein and on the proliferation of bladder cancer T24 cells,and research the function of DNMT3b in the process of bladder tumor formation.Methods There were three groups in this study,which are blank controller,HK and pshRNA-DNMT3b(24h,48h,72h),respectively.T24 cells were cultured routinely and transfected by the recombinant plasmids with lipfectamine 2000.The cells were detected by methods of RT-PCR,western blot and MTT.The varying level of DNMT3b mRNA and expression protein,and the conditions of cellular survival rate were observed.Results The recombinant plasmids were successfully transfected into T24 cell lines.The grey valHe of RT-PCR elctrophoretogram was analyzed by the software of Gel-pro analyzer,the rate of blank controller,HK and pshRNA-DNMT3b(24h,48h,72h),was (99.56±1.24)%,(99.12±1.35)%,(75.77±1.42)%,(44.69±1.05)%and(20.52±0.89)%,respectively.The analytical resuit of western blot image was(99.43±1.28)%,(98.90±1.31)%,(67.83±1.02)%,(43.43±1.05)%and(21.92±0.89)%.There was no statistically difference in survival between blank control and HK(P＞0.05).The group of pshRNA-DNMT3b and other two groups had statistical difference only at the 72th hour and the cell inhibitory growth rate only increase 0.45%.Conclusions The recombinant ptasmid pshRNA-DNMT3b can inhibit the expression of mRNA and protein of DNMT3b effectively.However,it has slight function on inhibiting cell proliferation.
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The cytokine repertoire of ADP/ATP carrier-specific humoral immune responses and the cytokine-dependent anti-ADP/ATP carrier antibody IgG subclasses were examined in a cohort of ADP/ATP carrier-immunized BALB/c mice treated with anti-CD4 monoclonal antibody. Eighteen male BALB/c mice (6-8 weeks old) were randomized into 3 groups: dilated cardiomyopathy (DCM) group, DCM-tolerance (Tol) group and control group. The mice in DCM group were immunized with the peptides derived from human ADP/ATP carrier protein for 6 months and mice in the control group were sham-immunized, while the mice in DCM-Tol group were immunized with ADP/ATP carrier protein and anti-CD4 McAb simultaneously. Serum autoantibody against ADP/ATP carrier and IgG subclasses were measured by ELISA, intracellular cytokines IFN-gamma and IL-4 of Th cells were monitored with flow cytometry, and splenic T cell cytokines IFN-gamma, IL-2, IL-4 and IL-6 were detected by using real-time fluorescent quantitative PCR. The results showed that the autoantibody against ADP/ATP carrier was found in all mice in DCM group, and the antibody level, serum IgG1 and IgG2a subclasses, cytokines in T cells and Th cells were all elevated in DCM group, as compared with those in control group (P<0.01). On the other hand, in DCM-Tol group, the autoantibody level and contents of all the cytokines were significantly different from those in DCM group (P<0.01), and were close to those in control group. And the levels of IgG1, IgG2a, IgG2b and IgG3 were influenced, to varying degrees, by anti-CD4 McAb as compared with those in DCM group. All these four types of IgG subclasses were substantially decreased in DCM-Tol group as compared with DCM group. It is concluded that the treatment with anti-CD4 McAb could prevent the activation of T cells, reverse the abnormal secretion of cytokines and the imbalance between Th1/Th2 cell subsets and abnormal production of autoantibody against ADP/ATP carrier, and eventually avoid myocardial injuries.
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In order to detect the expression of Oct4 in bladder cancer tissue and cell line BIU-87, immunohistochemistry was used in 49 bladder cancer biopsy samples and immunofluorescence and reverse transcription-PCR were performed on bladder cancer cell line BIU-87. Forty of 49 bladdercancer samples showed the expression of Oct4 in about 0.6% cancer cells. The positive rate and den-sity of Oct4 expression had no obvious relationship with the grade, recurrence or metastasis of blad-der cancer (P0.05). A few Oct4 positive cells were found in bladder cancer cell line BlU-87, which was also confirmed by RT-PCR. This study indicated the existence of few Oct4 positive cells in bladder cancer, which may be the bladder cancer stem cells. This study may provide the foundation for isolation and identification of bladder cancer stem cells.
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To explore the effects of Taushinone ⅡA on the proliferation, apoptosis and gene ex- pression of p53 and bcl-2 in human gastric carcinoma MKN-45 cells. Cell count and MTT assay were used to study the proliferation-inhibiting effect of Tanshinone ⅡA on MKN-45 cells. The effect of Tanshinone ⅡA on the cell cycle and apoptosis of MKN-45 cells were examined by propidium io- dide (PI) staining and flow cytometry. Semi-quantitative RT-PCR was used to further verify the ex- pression of p53 and bcl-2 gene after exposure to Tanshinone ⅡA in MKN-45 cells. The results showed that Tanshinone ⅡA significantly inhibited the growth and proliferation of MKN-45 cells in a dose- and time-dependent manner (P<0.05). Tanshinone ⅡA arrested MKN-45 cells in G2/M phase which led to an obvious accumulation of G2/M phase cells while decreased number of G0/G1 phase cells. This resulted in apoptosis of MKN-45 cells and the apoptosis rate was as high as 43.91% after treatment with 2.0 μg/mL Tanshinone ⅡA for 96 h. It was also found that Tanshinone ⅡA up-regulated expression of p53 gene and down-regulated expression of bcl-2 gene. The cytostatic and antiproliferative effect of Tanshinone ⅡA makes it a promising anticancer agent for the treatment of gastric carcinoma.
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The effect of vascular endothelial growth factor (VEGF) overexpression on matrix metalloproteinase-2 (MMP-2) in nasopharyngeal carcinoma (NPC) cells in vitro and the possible mechanism involved were investigated, and the correlation between the expression of VEGF and MMP-2 in NPC evaluated. The NPC cells were transfected with PAd-trackVEGF165 plasmid. The expression levels of VEGF and MMP-2 mRNA and protein in NPC cells were detected by semi-quantitative RT-PCR and Western blot respectively. It was found that the expression of VEGF and MMP-2 mRNA and protein was significantly increased in NPC cells after transfection of VEGF165. It was concluded that the expression of VEGF was correlated to the in vitro invasion of NPC cells, and the induction of MMP-2 by VEGF was a key process of NPC cell invasion.
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The expression of the cytokines IL-2, IL-10, TNF-alpha and their roles in mice with herpes simplex viral encephalitis (HSE) were studied. By using semiquantitative reverse transcription polymerase chain reaction (RT-PCR), the expressions of IL-2, IL-10 and TNF-alpha mRNA in control group, HSE group and acyclovir (ACV)-treated group were detected and the pathological changes of brain were observed. It was found that after HSV1 infection, the cerebral lesions of haemorrhage and necrosis in mice were observed under the microscopy, and the levels of IL-2, IL-10 and TNF-alpha were increased remarkably. After treatment with ACV after HSV1 infection, the cerebral lesions in mice were improved, the level of IL-2 maintained stable, IL-10 was increased consistently, and TNF-alpha was decreased significantly as compared with those in HSE group. In acute HSE, many cytokines are upregulated, including IL-2, IL-10 and TNF-alpha to eliminate virus and TH1 type response is dominant. In convalescence, there is a shift in the cytokine expression profile from TH1 profile to TH2 profile and the shift can inhibit the overexpression of immune response in animals. ACV has remarkable effects in the treatment of HSE.
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The effect of vascular endothelial growth factor (VEGF) overexpression on matrix metalloproteinase-2 (MMP-2) in nasopharyngeal carcinoma (NPC) cells in vitro and the possible mechanism involved were investigated, and the correlation between the expression of VEGF and MMP-2 in NPC evaluated. The NPC cells were transfected with PAd-trackVEGF165 plasmid. The expression levels of VEGF and MMP-2 mRNA and protein in NPC cells were detected by semi-quantitative RT-PCR and Western blot respectively. It was found that the expression of VEGF and MMP-2 mRNA and protein was significantly increased in NPC cells after transfection of VEGF165. It was concluded that the expression of VEGF was correlated to the in vitro invasion of NPC cells, and the induction of MMP-2 by VEGF was a key process of NPC cell invasion.
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The expression of the cytokines IL-2, IL-10, TNF-α and their roles in mice with herpes simplex viral encephalitis (HSE) were studied. By using semiquantitative reverse transcription polymerase chain reaction (RT-PCR), the expressions of IL-2, IL-10 and TNF-α mRNA in control group, HSE group and acyclovir (ACV)-treated group were detected and the pathological changes of brain were observed. It was found that after HSV1 infection, the cerebral lesions of haemorrhage and necrosis in mice were observed under the microscopy, and the levels of IL-2, IL-10 and TNF-α were increased remarkably. After treatment with ACV after HSV1 infection, the cerebral lesions in mice were improved, the level of IL-2 maintained stable, IL-10 was increased consistently, and TNF-α was decreased significantly as compared with those in HSE group. In acute HSE, many cytokines are upregulated, including IL-2, IL-10 and TNF-α to eliminate virus and TH1 type response is dominant. In convalescence, there is a shift in the cytokine expression profile from TH1 profile to TH2 profile and the shift can inhibit the overexpression of immune response in animals. ACV has remarkable effects in the treatment of HSE.
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The curcumin prodrugs, which could be selectively activated in tumor cells, were prepared to establish a basis for the targeted chemotherapy for cancer. On the basis of the molecular structure of curcumin, the N-maleoyl-L-valine-curcumin (NVC), N-maleoyl- glycine-curcumin (NGC) were chemically synthesized and identified by IR and NMR spectroscopy. After treatment with these two prodrugs for 6 - 24 h, the rates of growth inhibition on human bladder cancer EJ cells and renal tubular epithelial (HKC) cells were detected by MTT colorimetry. Our results showed that after the treatment with 20 micromol/L - 40 micromol/L NVC and NGC for 6 - 24 h, the growth inhibitory effects on EJ cells were 6.71% - 65.13% (P < 0.05), 10.96% - 73.01% (P < 0.05), respectively, in both dose- and time-dependent manners. When compared with the curcumin of same concentrations, the growth inhibitory effects of these two prodrugs on HKC cells were significantly decreased (P < 0.01). It is concluded that activation of curcumin prodrugs via hydrolysis functions of cellular esterase could inhibit the growth activities of tumor cells, and reduce the side effects on normal diploid cells. This provided a novel strategy for further exploration of tumor-targeted chemotherapeutic drugs.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Curcumin/pharmacology , Dose-Response Relationship, Drug , Prodrugs/chemical synthesis , Prodrugs/pharmacology , Tumor Cells, Cultured , Urinary Bladder Neoplasms/pathologyABSTRACT
To clone Uroplakin Ⅱ gene from Chinese transitional cell carcinoma (TCC) of bladder and construct its eukaryotic expression vector, the molecular cloning method was used to extract total RNA from a GⅢ/ T3N0M0 tissue sample of the bladder TCC patients. The primers were designed by Primer 5.0 software. Full length cDNA of Uroplakin Ⅱ gene was amplified by reverse transcription polymerase chain reaction (RT-PCR), assayed by nucleic acid sequencing and then inserted between Xba Ⅰ and HindⅢ restrictive sites of eukaryotic expression vector pcDNA3.0. The recombinant was assayed by restricted enzyme digestion. Under the induction of Lipofectamine 2000, the recombinant was transfected into Uroplakin Ⅱ negative bladder cancer cell line EJ. Cellular expression levels of Uroplakin Ⅱ were detected by RT-PCR. The nucleic acid sequencing results indicated that Chinese Uroplakin Ⅱ cDNA (555 bp) was successfully cloned. The BLAST analysis demonstrated that the cloned sequence is 100 % homologous with sequences reported overseas. The GenBank accession number AY455312 was also registered. The results of restricted enzyme digestion indicated that eukaryotic vector pcDNA-UP Ⅱ for Uroplakin Ⅱ was successfully constructed.After being transferred with pcDNA-UPⅡ for 72 h, cellular Uroplakin Ⅱ mRNA levels were significantly improved (P＜0.01). It is concluded that human Uroplakin Ⅱ gene was successfully cloned from Chinese TCC tissues, which provided a basis for further exploration of the roles of Uroplakin Ⅱ gene in TCC biological behaviors and potential strategies for targeted biological therapy of TCC.
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Summary: In order to study the expression of IL-1β and TNF-α in the myocardium of MCMV myocarditis and their role in the myocardial damages, 60 BALB/C mice of 4 weeks were randomly divided into two groups: 36 were injected intraperitoneally with MCMV and 24 served as control group. Immunohistochemistry was used to detect IL-1β and TNF-α expression in the myocardium, and myocardial lesions were observed histopathologically. Histopathological study on the myocardium from infected mice revealed focal or diffuse lesions characterized by inflammatory cells and degeneration or necrosis of myocytes. The myocardial lesion score showed the degree of inflammatory cell infiltration was slight in MCMV myocarditis.The positive staining signals for IL-1β and TNF-α proteins which mainly located in the infiltrating inflammatory cells and degenerative or necrotic myocytes were markedly detectable whereas there were no positive findings in the myocardium of control mice. IL-1β and TNF-α was expressed in the myocardium of viral myocarditis murine model induced by MCMV. IL-1β and TNF-α may play an important role in the pathogenesis of viral myocarditis.
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BACKGROUND: Microglial cells are prominently involved in certain neurologic diseases such as Parkinson disease and Alzeheimer disease. In vitro primary culture is commonly used in studies on the functions of microglia.However, these classical culture methods have some defects including complex procedures and low out-put.OBJECTIVE: To establish a simplified high-output primary culture of microglia.DESIGN: An explorative experiment with microglial cells as the single sample.SETTING: Department of Neurology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.MATERIALS: The study was finished at the Central Laboratory of Union Hospital from April to October 2004. Microglial cells were obtained from 10 newborn(one day) male Kunming mice that were selected.METHODS: The author' s culture method was based on McCarthy method, we developed a new culture method and made some improvements,including the increased cell density for primary culture and nutritional deprivation. The microlglial cells were isolated with low-concentration trypsin-EDTA(ethylene diamine tetraacetic acid) digestion and immunochemically labeled with MAC-1 antibody, so as to measure the output and purity of microglia.MAIN OUTCOME MEASURES: ① Morphologic features of microglial cells, observed with inverted microscope; ② Purity and activity of microglia cultured with these two methods, were measured immunohistochemically.RESULTS: For microglia cultured with McCarthy method, the culture cycle was 20 days and the output was 2 × l05 cells per flask with a purity of 95% -97%. The new method shortened the culture cycle to 15 days and the output reached 1 × 106 cells per flask with a purity of 96-98%. Cell purity and activity had no significant difference between these two culture methods.CONCLUSION: The new method has a similar purity and activity with classical method; however, it may simplify procedures, shorten cycle, and increase output, and therefore can be a useful method for studies on microglia function and for nerve repair.
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The curcumin prodrugs, which could be selectively activated in tumor cells, were prepared to establish a basis for the targeted chemotherapy for cancer. On the basis of the molecular structure of curcumin, the N-maleoyl-L-valine-curcumin (NVC), N-maleoyl- glycine-curcumin (NGC) were chemically synthesized and identified by IR and NMR spectroscopy. After treatment with these two prodrugs for 6-24 h, the rates of growth inhibition on human bladder cancer EJ cells and renal tubular epithelial (HKC) cells were detected by MTT colorimetry. Our results showed that after the treatment with 20 μmol/L- 40 μmol/L NVC and NGC for 6 - 24 h, the growth inhibitory effects on EJ cells were 6.71% -65.13 % (P＜0.05), 10.96 % -73.01% (P ＜0.05), respectively, in both dose- and time-dependent manners. When compared with the curcumin of same concentrations, the growth inhibitory effects of these two prodrugs on HKC cells were significantly decreased (P＜0.01). It is concluded that activation of curcumin prodrugs via hydrolysis functions of cellular esterase could inhibit the growth activities of tumor cells, and reduce the side effects on normal diploid cells. This provided a novel strategy for further exploration of tumortargeted chemotherapeutic drugs.
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<p><b>OBJECTIVE</b>In order to explore the possible roles played by the autoimmune mechanism in the progression of myocarditis into dilated cardiomyopathy (DCM) using an animal model, we investigated whether autoimmune myocarditis might develop into DCM.</p><p><b>METHODS</b>Experimental Balb/C mice (n = 20) were immunized with cardiac myosin with Freund's complete adjuvant at days 0, 7 and 30. The control Balb/C mice (n = 10) were immunized with Freund's complete adjuvant in the same mannere. Serum and myocardium samples were collected after the first immunization at days 15, 21 and 120. The anti-myosin antibody was examined by enzyme-linked immunosorbent assay and immunoblotting.</p><p><b>RESULTS</b>Pathological findings demonstrated that there was myocardial necrosis or inflammatory infiltration during acute stages and fibrosis mainly in the late phase of experimental group, but the myocardial lesions were not found in the control group. Autoimmunity could induce myocarditis and DCM in the absence of viral infection. High titer anti-myosin IgG antibodies were found in the experimental group, but not in the control group. Furthermore, the anti-myosin heavy chain (200 KD) antibody was positive in 21 of 48 patients with DCM and viral myocarditis, but only 4 of 20 patients with coronary heart disease, including 1 case and 3 cases that reacted with heavy and light chains (27.5 KD), respectively. The antibodies were not detected in healthy donors.</p><p><b>CONCLUSION</b>Cardiac myosin might be an autoantigen that provokes autoimmunity and leads to the transformation of myocarditis into DCM. Detection of anti-myosin heavy chain antibody might contribute to diagnosis for DCM and viral myocarditis.</p>