Dioscin is a natural steroid saponin derived from several plants, showing potent anti-cancer effect against a variety of tumor cell lines. In the present study, we investigated the anti-cancer activity of dioscin agai...Dioscin is a natural steroid saponin derived from several plants, showing potent anti-cancer effect against a variety of tumor cell lines. In the present study, we investigated the anti-cancer activity of dioscin against human LNCaP cells, and evaluated the possible mechanism involved in its antineoplastic action. It was found that dioscin（1, 2 and 4 μmol/L） could significantly inhibit the viability of LNCaP cells in a time- and concentration-dependent manner. Flow cytometry revealed that the apoptosis rate was increased after treatment of LNCaP cells with dioscin for 24 h, indicating that apoptosis was an important mechanism by which dioscin inhibited cancer. Western blotting was employed to detect the expression of caspase-3, Bcl-2 and Bax in LNCaP cells. The expression of cleaved caspase-3 was significantly increased, and meanwhile procaspase-3 was markedly decreased. The expression of anti-apoptotic protein Bcl-2 was down-regulated, whereas the pro-apoptotic protein Bax was up-regulated. Moreover, the Bcl-2/Bax ratio was drastically decreased. These results suggested that dioscin possessed potential anti-tumor activity in human LNCaP cells through the apoptosis pathway, which might be associated with caspase-3 and Bcl-2 protein family.展开更多
Objective To study whether there is the apoptosis of neural cells and the expression of Bcl-2 protein in intracerebral hemorrhage (ICH) in model of rats, for the further understanding the mechanism of the delayed dama...Objective To study whether there is the apoptosis of neural cells and the expression of Bcl-2 protein in intracerebral hemorrhage (ICH) in model of rats, for the further understanding the mechanism of the delayed damage of the neural cells around the hematoma after ICH. Methods Fifty SD rats were randomly divided into 5 groups, ten in each. With the Group A as the control, the rest 40 were used to set up intracerebral hemorrhage model. The brains were taken out at 12 th , 24 th , 48 th and 72 th hours, respectively. Apoptosis cells were detected with terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL), and the expression of Bcl-2 protein was detected with immunochemical stainging methed (SP). Results In the control group, no apoptosis cells and Bc1-2 protein were detected. In rest groups, the apoptosis cells and Bc1-2 protein were expressed in different degree. Apoptosis rates verified and corresponded with the time after ICH, with the peak at 48 th -72 th hour after hemorrhage. The peak rate of apoptosis cells was (24.50±2.69)% and Bcl-2 protein expression was (20.76±1.97)% . There was significant difference between the experimental groups and control (P<0.05), and no linear relationship between the apoptosis rate and the expression of Bcl-2 protein. Conclusion Apoptosis may be an important factor in the secondary trauma of ICH. There is a time leg after hemorrhage. All this is instructive to clinical treatment in time. Bcl-2 protein keeps increasing in a certain time after hemorrhage, but not synchronize with the cell apoptosis. This indicates that bcl-2 has the effect to reduce the apoptosis of neural cells.展开更多
AIM: To analyze the protein expression essential for apoptosis in liver steatosis. METHODS: The expression of proapoptotic proteins p53, Bax, and antiapoptotic Bcl-2 in hepatocytes with steatosis (SH) and without stea...AIM: To analyze the protein expression essential for apoptosis in liver steatosis. METHODS: The expression of proapoptotic proteins p53, Bax, and antiapoptotic Bcl-2 in hepatocytes with steatosis (SH) and without steatosis (NSH) was evaluated in 84 patients at various stages of non-alcoholic fatty liver disease (NAFLD). RESULTS: Immunohistochemical staining of liver tissue showed the activation of p53 protein in SH and NSH with increased liver steatosis, diminished Bcl-2 and slightly decreased Bax protein. Positive correlation was found between the stage of liver steatosis with p53 expression in SH (r = 0.54, P < 0.01) and NSH (r = 0.49, P < 0.01). The antiapoptotic protein Bcl-2 was diminished together with the advancement of liver steatosis, especially in non-steatosed hepatocytes (r =0.43, P < 001). CONCLUSION: Apoptosis is one of the most important mechanisms leading to hepatocyte elimination in NAFLD. The intensification of inflammation in NAFLD induces proapoptotic protein p53 with the inhibition of antiapoptotic Bcl-2.展开更多
The fresh water polyp Hydra belongs to the phylum Cnidaria, which diverged from the metazoan lineage before the appearance of bilaterians. In order to understand the evolution of apoptosis in metazoans, we have begun ...The fresh water polyp Hydra belongs to the phylum Cnidaria, which diverged from the metazoan lineage before the appearance of bilaterians. In order to understand the evolution of apoptosis in metazoans, we have begun to elucidate the molecular cell death machinery in this model organism. Based on ESTs and the whole Hydra genome assembly, we have identified 15 caspases. We show that one is activated during apoptosis, four have characteristics of initiator caspases with N-terminal DED, CARD or DD domain and two undergo autoprocessing in vitro. In addition, we describe seven Bcl-2-1ike and two Bak-like proteins. For most of the Bcl-2 family proteins, we have observed mitochondrial localization. When expressed in mammalian cells, HyBak-like 1 and 2 strongly induced apoptosis. Six of the Bcl-2 family members inhibited apoptosis induced by camptothecin in mammalian ceils with HyBcl-2-1ike 4 showing an especially strong protective effect. This protein also interacted with HyBak-like 1 in a yeast two-hybrid assay. Mutation of the conserved leucine in its BH3 domain abolished both the interaction with HyBak-like 1 and the anti-apoptotic effect. Moreover, we describe novel Hydra BH-3-only proteins. One of these interacted with Bcl-2-1ike 4 and induced apoptosis in mammalian cells. Our data indicate that the evolution of a complex network for cell death regulation arose at the earliest and simplest level of multicellular organization, where it exhibited a substantially higher level of complexity than in the protostome model organisms Caenorhabditis and Drosophila.展开更多
Objective To study the effects of P53, PCNA, Bc1-2 protein and their relationship in salivary adenoid cystic carclnoma(SACC). Methods These protelns were examlned by lmmunohistochemistry. Results overexpressions of Ps...Objective To study the effects of P53, PCNA, Bc1-2 protein and their relationship in salivary adenoid cystic carclnoma(SACC). Methods These protelns were examlned by lmmunohistochemistry. Results overexpressions of Ps, and PCNA were revealed in ACC samples, they were higher than those in (polymorphous adenomas) PA, but expression of Bc1-2 protein was not different between ACC and PA. In 3 subtypes of ACC, expressions of 3 proteins were different. Conciusion Mutations of P53, Bc1-2 may be involed in the occurrence of SACC, expression of PCNA and mutation of P53 may coexist in the development of the SACC.展开更多
AIM: Mechanisms responsible for persistence of HCV infection and liver damage in chronic hepatitis C are not clear. Apoptosis is an important form of host immune response against viral infections. Anti-apoptotic prote...AIM: Mechanisms responsible for persistence of HCV infection and liver damage in chronic hepatitis C are not clear. Apoptosis is an important form of host immune response against viral infections. Anti-apoptotic protein bcl-2 expression on liver tissue as well as the influence of interferon alpha 2b (IFNa2b) and ribavirin (RBV) were analyzed in patients with chronic hepatitis C. METHODS: In 30 patients with chronic hepatitis C (responders - R and non-responders - NR) treated with IFNα2b+RBV, protein bcl-2 was determined in hepatocytes and in liver associated lymphocytes before and after the treatment. RESULTS: The treatment diminished bcl-2 protein accumulation in liver cells in_patients with hepatitis C (P<0.05). Before and after the therapy, we detected bcl-2 protein in R in 87±15% and 83±20% of hepatocytes and in 28±18% and 26±10% of liver-associated lymphocytes, respectively. In NR, the values before treatment decreased from 94±32% to 88±21% of hepatocytes and 39±29% to 28±12% of lymphocytes with bcl-2 expression. There was no statistical correlation between bcl-2 expression on liver tissue with inflammatory activity, fibrosis and biochemical parameters before and after the treatment. CONCLUSION: IFNα2b+RBV treatment, by bcl-2 protein expression decrease, enables apoptosis of hepatocytes and associated liver lymphocytes, which in turn eliminate hepatitis C viruses.展开更多
OBJECTIVE To determine whether Bc1-2 protein down-regulation can render NCI-460 cells more susceptible to gamma radiation-induced apoptosis by treatment with antisense oligonucleotide （ASODN） against the coding regi...OBJECTIVE To determine whether Bc1-2 protein down-regulation can render NCI-460 cells more susceptible to gamma radiation-induced apoptosis by treatment with antisense oligonucleotide （ASODN） against the coding region of Bcl-2 mRNA. METHODS Cell survival was determined using the trypan blue dye exclusion. Expression of the Bcl-2 protein was assayed using immunofluo- rescence labeling with fluoresce isothiocyanate. Apoptosis was determined by Giemsa staining and flow cytomertry. RESULTS It was found that Bcl-2 ASODN combined with radiation sig- nificantly reduced the number of viable cells （P〈0.05）. There was no difference in cell survival between a nonsense oligodeoxynucleotide/radiation combination and cells treated with radiation alone. Bcl-2 ASODN combined with radiation significantly inhibited expression of the Bcl-2 protein in the NCI-H460 cells （P〈0.05）. Using Giemsa staining, cells treated with Bcl-2 ASODN combined with radiation at 72 h displayed classic apoptotic changes. Apoptotic rates of the NCI-H460 cells treated with Bcl-2 ASODN combined with radiation significantly increased （P〈 0.05）, compared with either a nonsense oligodeoxynucleotide/radiation combination or radiation-treatment cells alone. CONCLUSION ASODN against the coding region of Bcl-2 mRNA increases radiation-induced apoptosis in NCI-H460 cells.展开更多
In this study, we sought to elucidate the effects of melatonin on learning and memory as well as apoptosis and expression of the Bax or Bcl-2 proteins in the subgranular zone of the dentate gyrus in pinealectomized ra...In this study, we sought to elucidate the effects of melatonin on learning and memory as well as apoptosis and expression of the Bax or Bcl-2 proteins in the subgranular zone of the dentate gyrus in pinealectomized rats. Using the Morris water maze and the olfactory memory tests, we found that the average escape latency in pinealectomized rats was clearly increased compared with sham-operated rats. Moreover, the average escape latency in the melatonin-treated and pinealectomized rats was longer than that in the sham-operated rats and shorter than that in the pinealectomized and untreated rats. Immunohistochemistry and terminal-deoxynucleoitidyl transferase mediated nick end labeling （TUNEL） showed that there were fewer Bax immunoreactive cells and TUNEL-positive （apoptotic） cells but more Bcl-2 immunoreactive cells in the melatonin-treated rats compared with the pinealectomized rats. The sham-operated rats showed numbers of these cells similar to the melatonin-treated rats. These experimental findings demonstrate that melatonin treatment may reduce abnormal apoptosis by promoting gene expression of Bax and suppressing gene expression of Bcl-2 in the subgranular zone of the dentate gyrus in pinealectomized rats. These effects appear to result in the inhibition of cellular apoptosis and the improvement of spatial learning and memory in pinealectomized rats.展开更多
基金supported by the National Natural Science Foundation of China(No.81173065)
文摘Dioscin is a natural steroid saponin derived from several plants, showing potent anti-cancer effect against a variety of tumor cell lines. In the present study, we investigated the anti-cancer activity of dioscin against human LNCaP cells, and evaluated the possible mechanism involved in its antineoplastic action. It was found that dioscin（1, 2 and 4 μmol/L） could significantly inhibit the viability of LNCaP cells in a time- and concentration-dependent manner. Flow cytometry revealed that the apoptosis rate was increased after treatment of LNCaP cells with dioscin for 24 h, indicating that apoptosis was an important mechanism by which dioscin inhibited cancer. Western blotting was employed to detect the expression of caspase-3, Bcl-2 and Bax in LNCaP cells. The expression of cleaved caspase-3 was significantly increased, and meanwhile procaspase-3 was markedly decreased. The expression of anti-apoptotic protein Bcl-2 was down-regulated, whereas the pro-apoptotic protein Bax was up-regulated. Moreover, the Bcl-2/Bax ratio was drastically decreased. These results suggested that dioscin possessed potential anti-tumor activity in human LNCaP cells through the apoptosis pathway, which might be associated with caspase-3 and Bcl-2 protein family.
文摘Objective To study whether there is the apoptosis of neural cells and the expression of Bcl-2 protein in intracerebral hemorrhage (ICH) in model of rats, for the further understanding the mechanism of the delayed damage of the neural cells around the hematoma after ICH. Methods Fifty SD rats were randomly divided into 5 groups, ten in each. With the Group A as the control, the rest 40 were used to set up intracerebral hemorrhage model. The brains were taken out at 12 th , 24 th , 48 th and 72 th hours, respectively. Apoptosis cells were detected with terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL), and the expression of Bcl-2 protein was detected with immunochemical stainging methed (SP). Results In the control group, no apoptosis cells and Bc1-2 protein were detected. In rest groups, the apoptosis cells and Bc1-2 protein were expressed in different degree. Apoptosis rates verified and corresponded with the time after ICH, with the peak at 48 th -72 th hour after hemorrhage. The peak rate of apoptosis cells was (24.50±2.69)% and Bcl-2 protein expression was (20.76±1.97)% . There was significant difference between the experimental groups and control (P<0.05), and no linear relationship between the apoptosis rate and the expression of Bcl-2 protein. Conclusion Apoptosis may be an important factor in the secondary trauma of ICH. There is a time leg after hemorrhage. All this is instructive to clinical treatment in time. Bcl-2 protein keeps increasing in a certain time after hemorrhage, but not synchronize with the cell apoptosis. This indicates that bcl-2 has the effect to reduce the apoptosis of neural cells.
文摘AIM: To analyze the protein expression essential for apoptosis in liver steatosis. METHODS: The expression of proapoptotic proteins p53, Bax, and antiapoptotic Bcl-2 in hepatocytes with steatosis (SH) and without steatosis (NSH) was evaluated in 84 patients at various stages of non-alcoholic fatty liver disease (NAFLD). RESULTS: Immunohistochemical staining of liver tissue showed the activation of p53 protein in SH and NSH with increased liver steatosis, diminished Bcl-2 and slightly decreased Bax protein. Positive correlation was found between the stage of liver steatosis with p53 expression in SH (r = 0.54, P < 0.01) and NSH (r = 0.49, P < 0.01). The antiapoptotic protein Bcl-2 was diminished together with the advancement of liver steatosis, especially in non-steatosed hepatocytes (r =0.43, P < 001). CONCLUSION: Apoptosis is one of the most important mechanisms leading to hepatocyte elimination in NAFLD. The intensification of inflammation in NAFLD induces proapoptotic protein p53 with the inhibition of antiapoptotic Bcl-2.
文摘The fresh water polyp Hydra belongs to the phylum Cnidaria, which diverged from the metazoan lineage before the appearance of bilaterians. In order to understand the evolution of apoptosis in metazoans, we have begun to elucidate the molecular cell death machinery in this model organism. Based on ESTs and the whole Hydra genome assembly, we have identified 15 caspases. We show that one is activated during apoptosis, four have characteristics of initiator caspases with N-terminal DED, CARD or DD domain and two undergo autoprocessing in vitro. In addition, we describe seven Bcl-2-1ike and two Bak-like proteins. For most of the Bcl-2 family proteins, we have observed mitochondrial localization. When expressed in mammalian cells, HyBak-like 1 and 2 strongly induced apoptosis. Six of the Bcl-2 family members inhibited apoptosis induced by camptothecin in mammalian ceils with HyBcl-2-1ike 4 showing an especially strong protective effect. This protein also interacted with HyBak-like 1 in a yeast two-hybrid assay. Mutation of the conserved leucine in its BH3 domain abolished both the interaction with HyBak-like 1 and the anti-apoptotic effect. Moreover, we describe novel Hydra BH-3-only proteins. One of these interacted with Bcl-2-1ike 4 and induced apoptosis in mammalian cells. Our data indicate that the evolution of a complex network for cell death regulation arose at the earliest and simplest level of multicellular organization, where it exhibited a substantially higher level of complexity than in the protostome model organisms Caenorhabditis and Drosophila.
文摘Objective To study the effects of P53, PCNA, Bc1-2 protein and their relationship in salivary adenoid cystic carclnoma(SACC). Methods These protelns were examlned by lmmunohistochemistry. Results overexpressions of Ps, and PCNA were revealed in ACC samples, they were higher than those in (polymorphous adenomas) PA, but expression of Bc1-2 protein was not different between ACC and PA. In 3 subtypes of ACC, expressions of 3 proteins were different. Conciusion Mutations of P53, Bc1-2 may be involed in the occurrence of SACC, expression of PCNA and mutation of P53 may coexist in the development of the SACC.
文摘AIM: Mechanisms responsible for persistence of HCV infection and liver damage in chronic hepatitis C are not clear. Apoptosis is an important form of host immune response against viral infections. Anti-apoptotic protein bcl-2 expression on liver tissue as well as the influence of interferon alpha 2b (IFNa2b) and ribavirin (RBV) were analyzed in patients with chronic hepatitis C. METHODS: In 30 patients with chronic hepatitis C (responders - R and non-responders - NR) treated with IFNα2b+RBV, protein bcl-2 was determined in hepatocytes and in liver associated lymphocytes before and after the treatment. RESULTS: The treatment diminished bcl-2 protein accumulation in liver cells in_patients with hepatitis C (P<0.05). Before and after the therapy, we detected bcl-2 protein in R in 87±15% and 83±20% of hepatocytes and in 28±18% and 26±10% of liver-associated lymphocytes, respectively. In NR, the values before treatment decreased from 94±32% to 88±21% of hepatocytes and 39±29% to 28±12% of lymphocytes with bcl-2 expression. There was no statistical correlation between bcl-2 expression on liver tissue with inflammatory activity, fibrosis and biochemical parameters before and after the treatment. CONCLUSION: IFNα2b+RBV treatment, by bcl-2 protein expression decrease, enables apoptosis of hepatocytes and associated liver lymphocytes, which in turn eliminate hepatitis C viruses.
基金This work was supported by the Natural Science Program Foundation of the Guangdong Province (021195)Natural Science Program Foundation of the Guangdong Province (04010446).
文摘OBJECTIVE To determine whether Bc1-2 protein down-regulation can render NCI-460 cells more susceptible to gamma radiation-induced apoptosis by treatment with antisense oligonucleotide （ASODN） against the coding region of Bcl-2 mRNA. METHODS Cell survival was determined using the trypan blue dye exclusion. Expression of the Bcl-2 protein was assayed using immunofluo- rescence labeling with fluoresce isothiocyanate. Apoptosis was determined by Giemsa staining and flow cytomertry. RESULTS It was found that Bcl-2 ASODN combined with radiation sig- nificantly reduced the number of viable cells （P〈0.05）. There was no difference in cell survival between a nonsense oligodeoxynucleotide/radiation combination and cells treated with radiation alone. Bcl-2 ASODN combined with radiation significantly inhibited expression of the Bcl-2 protein in the NCI-H460 cells （P〈0.05）. Using Giemsa staining, cells treated with Bcl-2 ASODN combined with radiation at 72 h displayed classic apoptotic changes. Apoptotic rates of the NCI-H460 cells treated with Bcl-2 ASODN combined with radiation significantly increased （P〈 0.05）, compared with either a nonsense oligodeoxynucleotide/radiation combination or radiation-treatment cells alone. CONCLUSION ASODN against the coding region of Bcl-2 mRNA increases radiation-induced apoptosis in NCI-H460 cells.
文摘In this study, we sought to elucidate the effects of melatonin on learning and memory as well as apoptosis and expression of the Bax or Bcl-2 proteins in the subgranular zone of the dentate gyrus in pinealectomized rats. Using the Morris water maze and the olfactory memory tests, we found that the average escape latency in pinealectomized rats was clearly increased compared with sham-operated rats. Moreover, the average escape latency in the melatonin-treated and pinealectomized rats was longer than that in the sham-operated rats and shorter than that in the pinealectomized and untreated rats. Immunohistochemistry and terminal-deoxynucleoitidyl transferase mediated nick end labeling （TUNEL） showed that there were fewer Bax immunoreactive cells and TUNEL-positive （apoptotic） cells but more Bcl-2 immunoreactive cells in the melatonin-treated rats compared with the pinealectomized rats. The sham-operated rats showed numbers of these cells similar to the melatonin-treated rats. These experimental findings demonstrate that melatonin treatment may reduce abnormal apoptosis by promoting gene expression of Bax and suppressing gene expression of Bcl-2 in the subgranular zone of the dentate gyrus in pinealectomized rats. These effects appear to result in the inhibition of cellular apoptosis and the improvement of spatial learning and memory in pinealectomized rats.
