Dendritic cells (DCs) are the most potent antigen-presen ting cells that play crucial roles in the regulation of immune response. Triptol ide, an active component purified from the medicinal plant Tripterygium wilfor ...Dendritic cells (DCs) are the most potent antigen-presen ting cells that play crucial roles in the regulation of immune response. Triptol ide, an active component purified from the medicinal plant Tripterygium wilfor dii Hook F., has been demonstrated to act as a potent immunosuppressive drug c apab le of inhibiting T cell activation and proliferation. However, little is known a bout the effects of triptolide on DCs. The present study shows that triptolide d oes not affect phenotypic differentiation and LPS-induced maturation of murine DCs. But triptolide can dramatically reduce cell recovery by inducing apoptosis of DCs at concentration as low as 10 ng/ml, as demonstrated by phosphatidylserin e exposure, mitochondria potential decrease, and nuclear DNA condensation. Tript olide induces activation of p38 in DCs, which precedes the activation of caspase 3. SB203580, a specific kinase inhibitor for p38, can block the activation of caspase 3 and inhibit the resultant apoptosis of DCs. Our results suggest that t he anti-inflammatory and immunosuppressive activities of triptolide may be due, in part, to its apoptosis-inducing effects on DCs.展开更多
AIM: To investigate the anti-tumor effect and mechanisms of magnetic nanoparticles targeting hepatocellular carcinoma. METHODS: Human hepatocellular carcinoma was induced in nude mice, and the mice were randomly divid...AIM: To investigate the anti-tumor effect and mechanisms of magnetic nanoparticles targeting hepatocellular carcinoma. METHODS: Human hepatocellular carcinoma was induced in nude mice, and the mice were randomly divided into group A receiving normal saline, group B receiving magnetic nanoparticles containing 5-fluorouracil (5-FU), group C receiving 5-FU, and group D receiving magnetic nanoparticles containing 5-FU with a magnetic field built in tumor tissues. The tumor volume was measured on the day before treatment and 1, 4, 7, 10 and 13 d after treatment. Tumor tissues were isolated for examination of the expression of bcl-2, bax and caspase 3 by immunohistochemical method, reverse transcription polymerase chain reaction and Western blotting. RESULTS: The tumor volume was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01). The volume was markedly lower in group D than in group C (P < 0.05). The expression of protein and mRNA of bcl-2 was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01), and was markedly lower in group D than in group C (P < 0.01). The expression of bax and caspase 3 in groups C and D was signif icantly increased, compared with that in groups A and B (P < 0.01). CONCLUSION: The targeted magnetic nanoparticles containing 5-FU can improve the chemotherapeutic effect of 5-FU against hepatocellular carcinoma by decreasing the expression of bcl-2 gene, and increasing the expression of bax and caspase 3 genes.展开更多
BACKGROUND： Lentiviral vectors, a type of retroviral vector, are able to infect cells at all phases of cell cycle. They are able to express exogenous target genes in vivo over long periods of time with limited immuno...BACKGROUND： Lentiviral vectors, a type of retroviral vector, are able to infect cells at all phases of cell cycle. They are able to express exogenous target genes in vivo over long periods of time with limited immunological reaction. OBJECTIVE： To inhibit neuronal apoptosis by blocking the apoptotic cascade reaction, gene silencing of Caspase 3, and transfection of Caspase 3 short hairpin ribonucleic acid （shRNA） into Neuro 2a cells using a lentiviral vector.DESIGN： TiME-AND SETTING： An observational, genetic engineering cellular biology experiment was performed in Guangzhou Red Cross Hospital and Guangzhou Institute of Traumatic Surgery between March 2007 and June 2008. MATERIALS： PLL3.7, PCMV-VSV-G, and PH＇8.9∧PR plasmids were provided by the CBR Institute for Biomedical Research, Harvard Medical School, USA. Staurosporine was purchased from Sigma, USA.METHODS： Caspase 3 siRNA was synthesized and cloned into the PLL3.7 plasmid. The Caspase 3 shRNA-PLL3.7 Ientivirus was generated in 293T cells using a calcium phosphate transfection kit. After the lentivirus was transfected into Neuro 2a cells, apoptosis was induced in both the transfected and untransfected cells by staurosporine. Cell apoptosis was assessed by flow cvtometrv.MAIN OUTCOME MEASURES： Caspase 3 mRNA expression was measured by RT-PCR and Caspase protein expression was assessed by Western blot. Cellular apoptosis was determined by flow cytometry using Annevin V-PE/Taad-Cy7. RESULTS： The transfection rate of caspase 3 shRNA was 〉 98% using the lentiviral vector, RT-PCR and Western blot results demonstrated that significantly reduced Caspase 3 mRNA and protein expression in the transfected Neuro 2a. The control group exhibited 38.7% Annexin V/7aad-positive cells, which suggested apoptotic anaphase, while only 5.0% cells in the Caspase 3 gene silencing group entered apoptotic anaphase. CONCKUSION： Caspase 3 shRNA inhibited Caspase 3 expression in Neuro 2a ceils and decreased drug-induced apoptosis of Neuro 2a cells.展开更多
AIM: To evaluate the influence of an intravitreal injection of bevacizumab and fasudil on the retinal vascular endothelial growth factor(VEGF),tumor necrosis factor alpha(TNFα),and caspase 3 levels in a diabetic rabb...AIM: To evaluate the influence of an intravitreal injection of bevacizumab and fasudil on the retinal vascular endothelial growth factor(VEGF),tumor necrosis factor alpha(TNFα),and caspase 3 levels in a diabetic rabbit model. · METHODS: The study included 6 healthy rabbits(Group 1),6 rabbits with experimentally induced diabetes mellitus(DM)(Group 2),7 rabbits with experimentally induced DM to which intravitreal bevacizumab was administered(Group 3),and 7 rabbits with experimentally induced DM to which intravitreal fasudil was administered(Group 4). An intravitreal injection of 1.25mg/50μL bevacizumab in the right eye of rabbits in Group 3 and an intravitreal injection of 0.0064mg/50μL fasudil in the right eye of rabbits in Group 4 were administered on day 21 after the induction of DM. The studied eyes of the rabbits were enucleated three days after the intravitreal injection. The TNFα,VEGF,and caspase 3 levels were determined using the ELISA method. · RESULTS: There was a statistically significant difference in the VEGF and caspase 3 levels between groups(P =0.005 and P =0.013,respectively),but the TNF α level did not differ significantly between groups(P = 0.792). It was found that VEGF levels were significantly lower in Group 1 and Group 3 than in Group 2 using the Mann-Whitney U test with the Bonferroni correction(P = 0.004 for both comparison). There was no statistically significant difference between other groups with regard to VEGF levels(the P value ranged between 0.015 and 0.886). Although the P values of the caspase 3 levels were 0.015 for Group 1 and Group 4,0.038 for Group 2and Group 3,and 0.018 for Group 3 and Group 4,these P values remained above the threshold P value of 0.0083,which was the statistically significant level for post hoc tests. ·CONCLUSION: An intravitreal injection of bevacizumab decreased both the VEGF level,which plays a role in angiogenesis,and the caspase 3 level,which plays a role in apoptosis. Although not as effective as bevacizumab,fasudil had a beneficial effect on the VEGF levels but significantly increased the caspase 3 levels.展开更多
文摘Dendritic cells (DCs) are the most potent antigen-presen ting cells that play crucial roles in the regulation of immune response. Triptol ide, an active component purified from the medicinal plant Tripterygium wilfor dii Hook F., has been demonstrated to act as a potent immunosuppressive drug c apab le of inhibiting T cell activation and proliferation. However, little is known a bout the effects of triptolide on DCs. The present study shows that triptolide d oes not affect phenotypic differentiation and LPS-induced maturation of murine DCs. But triptolide can dramatically reduce cell recovery by inducing apoptosis of DCs at concentration as low as 10 ng/ml, as demonstrated by phosphatidylserin e exposure, mitochondria potential decrease, and nuclear DNA condensation. Tript olide induces activation of p38 in DCs, which precedes the activation of caspase 3. SB203580, a specific kinase inhibitor for p38, can block the activation of caspase 3 and inhibit the resultant apoptosis of DCs. Our results suggest that t he anti-inflammatory and immunosuppressive activities of triptolide may be due, in part, to its apoptosis-inducing effects on DCs.
基金Supported by the Hi-Tech Research and Development Program of China, NO.2002AA214061
文摘AIM: To investigate the anti-tumor effect and mechanisms of magnetic nanoparticles targeting hepatocellular carcinoma. METHODS: Human hepatocellular carcinoma was induced in nude mice, and the mice were randomly divided into group A receiving normal saline, group B receiving magnetic nanoparticles containing 5-fluorouracil (5-FU), group C receiving 5-FU, and group D receiving magnetic nanoparticles containing 5-FU with a magnetic field built in tumor tissues. The tumor volume was measured on the day before treatment and 1, 4, 7, 10 and 13 d after treatment. Tumor tissues were isolated for examination of the expression of bcl-2, bax and caspase 3 by immunohistochemical method, reverse transcription polymerase chain reaction and Western blotting. RESULTS: The tumor volume was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01). The volume was markedly lower in group D than in group C (P < 0.05). The expression of protein and mRNA of bcl-2 was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01), and was markedly lower in group D than in group C (P < 0.01). The expression of bax and caspase 3 in groups C and D was signif icantly increased, compared with that in groups A and B (P < 0.01). CONCLUSION: The targeted magnetic nanoparticles containing 5-FU can improve the chemotherapeutic effect of 5-FU against hepatocellular carcinoma by decreasing the expression of bcl-2 gene, and increasing the expression of bax and caspase 3 genes.
基金Open Foundation of Key Laboratory of Biomedical Engineering,Guangdong Province,No.21030400Key Project of Guangzhou Medical and Health Care Foundation,No. 2006-ZDi-04
文摘BACKGROUND： Lentiviral vectors, a type of retroviral vector, are able to infect cells at all phases of cell cycle. They are able to express exogenous target genes in vivo over long periods of time with limited immunological reaction. OBJECTIVE： To inhibit neuronal apoptosis by blocking the apoptotic cascade reaction, gene silencing of Caspase 3, and transfection of Caspase 3 short hairpin ribonucleic acid （shRNA） into Neuro 2a cells using a lentiviral vector.DESIGN： TiME-AND SETTING： An observational, genetic engineering cellular biology experiment was performed in Guangzhou Red Cross Hospital and Guangzhou Institute of Traumatic Surgery between March 2007 and June 2008. MATERIALS： PLL3.7, PCMV-VSV-G, and PH＇8.9∧PR plasmids were provided by the CBR Institute for Biomedical Research, Harvard Medical School, USA. Staurosporine was purchased from Sigma, USA.METHODS： Caspase 3 siRNA was synthesized and cloned into the PLL3.7 plasmid. The Caspase 3 shRNA-PLL3.7 Ientivirus was generated in 293T cells using a calcium phosphate transfection kit. After the lentivirus was transfected into Neuro 2a cells, apoptosis was induced in both the transfected and untransfected cells by staurosporine. Cell apoptosis was assessed by flow cvtometrv.MAIN OUTCOME MEASURES： Caspase 3 mRNA expression was measured by RT-PCR and Caspase protein expression was assessed by Western blot. Cellular apoptosis was determined by flow cytometry using Annevin V-PE/Taad-Cy7. RESULTS： The transfection rate of caspase 3 shRNA was 〉 98% using the lentiviral vector, RT-PCR and Western blot results demonstrated that significantly reduced Caspase 3 mRNA and protein expression in the transfected Neuro 2a. The control group exhibited 38.7% Annexin V/7aad-positive cells, which suggested apoptotic anaphase, while only 5.0% cells in the Caspase 3 gene silencing group entered apoptotic anaphase. CONCKUSION： Caspase 3 shRNA inhibited Caspase 3 expression in Neuro 2a ceils and decreased drug-induced apoptosis of Neuro 2a cells.
基金Supported by the Scientific Research Project Coordination Unit of Abant Izzet Baysal University
文摘AIM: To evaluate the influence of an intravitreal injection of bevacizumab and fasudil on the retinal vascular endothelial growth factor(VEGF),tumor necrosis factor alpha(TNFα),and caspase 3 levels in a diabetic rabbit model. · METHODS: The study included 6 healthy rabbits(Group 1),6 rabbits with experimentally induced diabetes mellitus(DM)(Group 2),7 rabbits with experimentally induced DM to which intravitreal bevacizumab was administered(Group 3),and 7 rabbits with experimentally induced DM to which intravitreal fasudil was administered(Group 4). An intravitreal injection of 1.25mg/50μL bevacizumab in the right eye of rabbits in Group 3 and an intravitreal injection of 0.0064mg/50μL fasudil in the right eye of rabbits in Group 4 were administered on day 21 after the induction of DM. The studied eyes of the rabbits were enucleated three days after the intravitreal injection. The TNFα,VEGF,and caspase 3 levels were determined using the ELISA method. · RESULTS: There was a statistically significant difference in the VEGF and caspase 3 levels between groups(P =0.005 and P =0.013,respectively),but the TNF α level did not differ significantly between groups(P = 0.792). It was found that VEGF levels were significantly lower in Group 1 and Group 3 than in Group 2 using the Mann-Whitney U test with the Bonferroni correction(P = 0.004 for both comparison). There was no statistically significant difference between other groups with regard to VEGF levels(the P value ranged between 0.015 and 0.886). Although the P values of the caspase 3 levels were 0.015 for Group 1 and Group 4,0.038 for Group 2and Group 3,and 0.018 for Group 3 and Group 4,these P values remained above the threshold P value of 0.0083,which was the statistically significant level for post hoc tests. ·CONCLUSION: An intravitreal injection of bevacizumab decreased both the VEGF level,which plays a role in angiogenesis,and the caspase 3 level,which plays a role in apoptosis. Although not as effective as bevacizumab,fasudil had a beneficial effect on the VEGF levels but significantly increased the caspase 3 levels.
