Ovarian follicle development is associated with the physiological functions of granulosa cells(GCs),including proliferation and apoptosis.The level of miR-24-3p in ovarian tissue of high-yielding Yorkshire×Landra...Ovarian follicle development is associated with the physiological functions of granulosa cells(GCs),including proliferation and apoptosis.The level of miR-24-3p in ovarian tissue of high-yielding Yorkshire×Landrace sows was significantly higher than that of low-yielding sows.However,the functions of miR-24-3p on GCs are unclear.In this study,using flow cytometry,5-ethynyl-2′-de-oxyuridine(EdU)staining,and cell count,we showed that miR-24-3p promoted the proliferation of GCs increasing the proportion of cells in the S phase and upregulating the expression of cell cycle genes,moreover,miR-24-3p inhibited GC apoptosis.Mechanistically,on-line prediction,bioinformatics analysis,a luciferase reporter assay,RT-qPCR,and Western blot results showed that the target gene of miR-24-3p in proliferation and apoptosis is cyclin-dependent kinase inhibitor 1B(P27/CDKN1B).Furthermore,the effect of miR-24-3p on GC proliferation and apoptosis was attenuated by P27 overexpression.These findings suggest that miR-24-3p regulates the physiological functions of GCs.展开更多
BACKGROUND Gastric carcinoma(GC)is the third most frequent cause of cancer-related death,highlighting the pressing need for novel clinical treatment options.In this regard,microRNAs(miRNAs)have emerged as a promising ...BACKGROUND Gastric carcinoma(GC)is the third most frequent cause of cancer-related death,highlighting the pressing need for novel clinical treatment options.In this regard,microRNAs(miRNAs)have emerged as a promising therapeutic strategy.Studies have shown that miRNAs can regulate related signaling pathways,acting as tumor suppressors or tumor promoters.AIM To explore the effect of miR-204-3p on GC cells.METHODS We measured the expression levels of miR-204-3p in GC cells using quantitative real-time polymerase chain reaction,followed by the delivery of miR-204-3p overexpression and miR-204-3p knockdown vectors into GC cells.CCK-8 was used to detect the effect of miR-204-3p on the proliferation of GC cells,and the colony formation ability of GC cells was detected by the clonal formation assay.The effects of miR-204-3p on GC cell cycle and apoptosis were detected by flow cytometry.The BABL/c nude mouse subcutaneous tumor model using MKN-45 cells was constructed to verify the effect of miR-204-3p on the tumorigenicity of GC cells.Furthermore,the study investigated the effects of miR-204-3p on various proteins related to the MAPK signaling pathway,necroptosis signaling pathway and apoptosis signaling pathway on GC cells using Western blot techniques.RESULTS Firstly,we found that the expression of miR-204-3p in GC was low.When treated with the lentivirus overexpression vector,miR-204-3p expression significantly increased,but the lentivirus knockout vector had no significant effect on miR-204-3p.In vitro experiments confirmed that miR-204-3p overexpression inhibited GC cell viability,promoted cell apoptosis,blocked the cell cycle,and inhibited colony formation ability.In vivo animal experiments confirmed that miR-204-3p overexpression inhibited subcutaneous tumorigenesis ability in BABL/c nude mice.Simultaneously,our results verified that miR-204-3p overexpression can inhibit GC cell proliferation by inhibiting protein expression levels of KRAS and p-ERK1/2 in the MAPK pathway,as well as inhibiting protein expression levels of p-RIP1 and p-MLK1 in the necroptosis pathway to promote the BCL-2/BAX/Caspase-3 apoptosis pathway.CONCLUSION MiR-204-3p overexpression inhibited GC cell proliferation by inhibiting the MAPK pathway and necroptosis pathway to promote apoptosis of GC cells.Thus,miR-204-3p may represent a new potential therapeutic target for GC.展开更多
Objective:To investigate the role of miR-129-5p in regulating HMGB1 expression in pancreatic cancer cell apoptosis.Methods:The untreated pancreatic cancer SW1990 cells were used as the control group.Mimics-NC(empty ve...Objective:To investigate the role of miR-129-5p in regulating HMGB1 expression in pancreatic cancer cell apoptosis.Methods:The untreated pancreatic cancer SW1990 cells were used as the control group.Mimics-NC(empty vector),miR-129-5p mimics,inhibitor-NC(empty vector)and miR-129-5p inhibitor were transfected into SW1990 cells by liposome transfection method as the mimics-NC group,miR-129-5p overexpression group(miR-129-5p mimics group),inhibitor-NC group and miR-129-5p low expression group(miR-129-5p inhibitor group).The binding site of miR-129-5p and HMGB1 was predicted by online target gene prediction website Target genes,and the targeting relationship between miR-129-5p and HMGB1 was verified by dual luciferase gene report experiment.The expression of miR-129-5p in each group was detected by qRT-PCR,and the expression of HMGB1 protein and apoptosis-related proteins Caspase 3 and Bcl-2 by Western blot.Hoechst staining was used to observe the changes of apoptosis.Results:Compared with the mimics-NC group and control group,miR-129-5p mimics transfection significantly up-regulated miR-129-5p level(P<0.01),inhibited HMGB1(P<0.01)and Bcl-2(P<0.05)protein expression,pro-moted Caspase 3 protein expression(P<0.05),and promoted apoptosis;compared with the inhibitor-NC group and control group,miR-129-5p inhibitor transfection significantly down-regulated miR-129-5p level(P<0.05),promoted HMGB1 and Bcl-2 protein expression(all P<0.05),inhibited Caspase 3protein expression(P<0.01),and inhibited apoptosis.The results of dual luciferase reporter gene assay showed that miR-129-5p could inhibit the fluorescence activity of wildtype HMGB1 cells and target the expression of HMGB1.Conclusion:miR-129-5p promotes the apoptosis of pancreatic cancer SW1990 cells by targeting inhibition of HMGB1 expression.展开更多
The modulatory role of bcl 2 gene in hepatocellular apoptosis of rats with glycochenodeoxycholate (GCDC) induced obstructive jaundice was investigated. The hepatocytes in normal rats and those with bile duct ligati...The modulatory role of bcl 2 gene in hepatocellular apoptosis of rats with glycochenodeoxycholate (GCDC) induced obstructive jaundice was investigated. The hepatocytes in normal rats and those with bile duct ligation for 7 days, 14 days and 21 days were isolated and obtained by in situ collagenase perfusion and primary culture. The expression of bcl 2 mRNA in the hepatocytes was detected by RT PCR. Primary culture was performed on the hepatocytes from normal rats and those with bile duct ligation for 14 days. 100 μmol/L GCDC was added to the hepatocytes for incubation for 24 h. The hepatocellular apoptotic ratio was measured by using FCM and hepatocellular apoptosis detected in situ by using TUNEL technique. Results showed that the expression of bcl 2 mRNA was not detectable in the hepatocytes of normal rats by RT PCR technique, while detectable in the hepatocytes of those with bile duct ligation (BDL) for 7, 14 and 21 days. Hepatocellular apoptosis in the BDL group was obviously decreased as compared with normal control group after addition of 100 μmol/L GCDC to the cells for 24 h. It was concluded that the hepatocytes in the BDL rats expressed bcl 2. During obstructive jaundice, expression of bcl 2 from the hepatocytes can inhibit the bile salt induced hepatocellular apoptosis.展开更多
In order to investigate the protective effect of hypoxic preconditioning on the cerebral ischemia-reperfusion injury, the expression of Bcl-2 and Bax was detected by using immunohistochemical staining after 3 h cerebr...In order to investigate the protective effect of hypoxic preconditioning on the cerebral ischemia-reperfusion injury, the expression of Bcl-2 and Bax was detected by using immunohistochemical staining after 3 h cerebral ischemia followed by 1, 6, 12, 24 and 48 h reperfusion respectively in rats treated with or without hypoxic preconditioning before cerebral ischemia. In addition, the apoptosis of neural cells and the behavioral scores for neurological functions recovery were evaluated by TUNEL staining and ＂crawling method＂, respectively. Compared with control group （cerebral ischemia-reperfusion without hypoxic preconditioning）, the expression of Bcl-2 was significantly increased, but that of Bax decreased in the hypoxic preconditioning group （cerebral ischemiareperfusion with hypoxie preconditioning）, both P〈0.05. The pre-treatment with hypoxic preconditioning could reduce the apoptosis of neural cells and promote the neurological function recovery as compared to control group. It was suggested that hypoxic preconditioning may have protective effects on the cerebral ischemia-reperfusion injury by inhibiting the apoptosis of neural cells, increase the expression of Bcl-2 and decrease the expression of Bax.展开更多
In order to study the effects of ethyl pyruvate on cardiomyocyte apoptosis following ischemia/reperfusion （I/R） in vitro and the expression of Bcl-2 and Bax proteins, isolated rat hearts were perfused in a Langendor...In order to study the effects of ethyl pyruvate on cardiomyocyte apoptosis following ischemia/reperfusion （I/R） in vitro and the expression of Bcl-2 and Bax proteins, isolated rat hearts were perfused in a Langendorff model. Twenty-four rats were randomly divided into 3 groups （n=8 in each group）： control group was perfused for 120 min. In the I/R group, after 30 min stabilization the injury was induced by 30 min global ischemia followed by 60 min reperfusion. Ethyl pyruvate （EP） group was set up with the same protocol as I/R group except that it was supplied with 2 mmol/L EP 15 rain before ischemia and throughout reperfusion. Myocardial malonaldehyde （MDA） content was measured. Myocardial apoptotic index （AI） was tested by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling （TUNEL） method. The expression of anti-apoptotic protein Bcl-2 and pro-apoptotic protein Bax in cardiac myocytes was detected by immunohistochemistry. As compared with control group, the content of MDA, myocardial AI and the expression of Bcl-2, Bax proteins were increased significantly in I/R group, but the content of MDA, myocardial AI and the expression of Bax protein were decreased obviously and the expression of Bcl-2 protein was up-regulated in EP group （P〈0.05）. These results demonstrate that EP could inhibit apoptosis of cardiac myocytes possibly via alleviating oxidative stress, up-regulating Bcl-2 and down-regulating Bax proteins.展开更多
BACKGROUND:Many Chinese herbs,especially herbal injections,have been shown to have anti-tumor effects in recent years.However,since most reports focus on the clinical effectiveness of these herbs,their mechanisms of a...BACKGROUND:Many Chinese herbs,especially herbal injections,have been shown to have anti-tumor effects in recent years.However,since most reports focus on the clinical effectiveness of these herbs,their mechanisms of action are not well understood.In this study,we assessed apoptosis in the hepatocellular carcinoma (HCC) cell line HepG2 induced by an injectable extract from the seed of Coix lacryma-jobi (Semen coicis,SC),and monitored the expression of Bcl-2 and caspase-8.METHODS:Injectable SC was applied to HepG2 cells at different concentrations and the cells were collected 12,24 and 48 hours later.5-fluorouracil was used as a positive control group,and fluorescence-activated cell-sorting cytometry was used to measure the apoptosis rate of HepG2 cells and the expression of Bcl-2 and caspase-8 proteins.RESULTS:SC induced apoptosis in HepG2 cells in a concentration and time-dependent manner,and the expression of caspase-8 was elevated and prolonged.However,it did not significantly influence the expression of Bcl-2.CONCLUSION:Injectable SC may induce apoptosis in HCC cells by regulating the expression of caspase-8.展开更多
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
To observe the effectof ginsenoside Re on cardiomyocyte apoptosis and Bcl- 2 / Bax gene expression after ischemia (30 m in) and reperfusion (6 h) in rats and to elucidate the possible m echanism s of ginsenoside Re ...To observe the effectof ginsenoside Re on cardiomyocyte apoptosis and Bcl- 2 / Bax gene expression after ischemia (30 m in) and reperfusion (6 h) in rats and to elucidate the possible m echanism s of ginsenoside Re on inhibition of cardiom yocyte apoptosis,the ischem ia/ reperfusion heart m odel was established by ligating the left anterior descending branch of coronary artery in Wistar rats.The apoptotic cardiom yocytes were confirmed by transm ission electron m icroscopy and counted by in situ nick end labeling(TU NEL) method and lightm icroscopy.The m RNA and protein expression of Bcl- 2 and Bax genes were studied by in situ hybridization and im munohis- tochemical staining.Mean optical density (OD) value of the positive fields of m RNA and protein expression was quantitatively exam ined by im age analysis system.The results were as follows: (1) The apoptotic cardiomyocytes were found in ischemic fields in the ischem ia/ reperfusion group and weren't observed in the sham- operation group by transmission electron microscopy;(2 ) The num bers of the apoptotic cells were134.4 5± 4 5 .6 1/ field in the ischemia/ reperfusion group,and 90 .6 6± 19.2 2 / field in the ginsenoside Re- treated group.The differences was significant between two groups(P<0 .0 1) ;(3) Gene expression of Bcl- 2 and Bax were increased significantly in the is- chemia/ reperfusion group and ginsenoside Re- treated group when compared with the sham - opera- tion group.There was no significant difference in the gene expression of Bcl- 2 between the gin- senoside Re- treated group and ischemia/ reperfusion group(P>0 .0 5 ) ,but gene expression of Bax was decreased significantly in the ginsenoside Re- treated group as compared with the ischem ia/ reperfusion group(P<0 .0 1) .The ratio of Bcl- 2 / Bax was increased significantly in the ginseno- side Re- treated group when com pared with the ischem ia/ reperfusion group and sham- operation group.These findings suggest that m yocardial ischem ia- reperfusion can induce cardiom yocyte apoptosis,and ginsenoside Re can significantly inhibit cardiom yocyte apoptosis induced by ischemi- a- reperfusion in rats.It is concluded that ginsenoside Re inhibits cardiomyocyte apoptosis by in- hibiting expression of pro- apoptotic Bax gene and raising the ratio of Bcl- 2 / Bax.展开更多
To investigate the relationship of bcl-2, p53, proliferating cell nuclear antigen (PCNA) to cell proliferation, apoptosis and pathological parameters, the patterns of cell growth and turnover in renal cell carcinoma (...To investigate the relationship of bcl-2, p53, proliferating cell nuclear antigen (PCNA) to cell proliferation, apoptosis and pathological parameters, the patterns of cell growth and turnover in renal cell carcinoma (RCC), formalin-fixed and paraffin-embedded tissue blocks from 34 patients with RCC were examined. Cell proliferation activity was detected by PCNA immunostaining and the proliferation index (PI) was expressed as a percentage of the PCNA-positive cells in the tumor cells. Apoptosis was detected by terminal deoxy- nucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and the apoptotic index (AI) was expressed as a percentage of the TUNEL-positive cells in the tumor cells. Expressions of bcl-2 and p53 were assessed immunohistochemically. Our results showed that the PI ranged from 6.0 % to 24.0 % (median 12.3 %) and the AI from 2.0 % to 8.0 % (median 5.4 %) in RCC. The expression of the bcl-2 protein was demonstrated in 15 cases (44.1 %); the expression of the p53 protein, however, was seen in only 3 case. bcl-2 positivity was not associated with PI or AI or any pathological parameters. There were close associations between PI and tumor grade and stage, and a significant relationship between AI and the tumor grade of RCC. Our study suggests that bcl-2 positivity was not associated with PI or AI or any pathological parameters. There are close associations between PI and AI and tumor grade and stage of RCC. Active cell proliferation may be accompanied by frequent apoptosis in RCC.展开更多
基金supported by the National Natural Science Foundation of China(32272849)the National Key R&D Program of China(2021YFF1000602)the earmarked fund for CARS-35-PIG。
文摘Ovarian follicle development is associated with the physiological functions of granulosa cells(GCs),including proliferation and apoptosis.The level of miR-24-3p in ovarian tissue of high-yielding Yorkshire×Landrace sows was significantly higher than that of low-yielding sows.However,the functions of miR-24-3p on GCs are unclear.In this study,using flow cytometry,5-ethynyl-2′-de-oxyuridine(EdU)staining,and cell count,we showed that miR-24-3p promoted the proliferation of GCs increasing the proportion of cells in the S phase and upregulating the expression of cell cycle genes,moreover,miR-24-3p inhibited GC apoptosis.Mechanistically,on-line prediction,bioinformatics analysis,a luciferase reporter assay,RT-qPCR,and Western blot results showed that the target gene of miR-24-3p in proliferation and apoptosis is cyclin-dependent kinase inhibitor 1B(P27/CDKN1B).Furthermore,the effect of miR-24-3p on GC proliferation and apoptosis was attenuated by P27 overexpression.These findings suggest that miR-24-3p regulates the physiological functions of GCs.
文摘BACKGROUND Gastric carcinoma(GC)is the third most frequent cause of cancer-related death,highlighting the pressing need for novel clinical treatment options.In this regard,microRNAs(miRNAs)have emerged as a promising therapeutic strategy.Studies have shown that miRNAs can regulate related signaling pathways,acting as tumor suppressors or tumor promoters.AIM To explore the effect of miR-204-3p on GC cells.METHODS We measured the expression levels of miR-204-3p in GC cells using quantitative real-time polymerase chain reaction,followed by the delivery of miR-204-3p overexpression and miR-204-3p knockdown vectors into GC cells.CCK-8 was used to detect the effect of miR-204-3p on the proliferation of GC cells,and the colony formation ability of GC cells was detected by the clonal formation assay.The effects of miR-204-3p on GC cell cycle and apoptosis were detected by flow cytometry.The BABL/c nude mouse subcutaneous tumor model using MKN-45 cells was constructed to verify the effect of miR-204-3p on the tumorigenicity of GC cells.Furthermore,the study investigated the effects of miR-204-3p on various proteins related to the MAPK signaling pathway,necroptosis signaling pathway and apoptosis signaling pathway on GC cells using Western blot techniques.RESULTS Firstly,we found that the expression of miR-204-3p in GC was low.When treated with the lentivirus overexpression vector,miR-204-3p expression significantly increased,but the lentivirus knockout vector had no significant effect on miR-204-3p.In vitro experiments confirmed that miR-204-3p overexpression inhibited GC cell viability,promoted cell apoptosis,blocked the cell cycle,and inhibited colony formation ability.In vivo animal experiments confirmed that miR-204-3p overexpression inhibited subcutaneous tumorigenesis ability in BABL/c nude mice.Simultaneously,our results verified that miR-204-3p overexpression can inhibit GC cell proliferation by inhibiting protein expression levels of KRAS and p-ERK1/2 in the MAPK pathway,as well as inhibiting protein expression levels of p-RIP1 and p-MLK1 in the necroptosis pathway to promote the BCL-2/BAX/Caspase-3 apoptosis pathway.CONCLUSION MiR-204-3p overexpression inhibited GC cell proliferation by inhibiting the MAPK pathway and necroptosis pathway to promote apoptosis of GC cells.Thus,miR-204-3p may represent a new potential therapeutic target for GC.
基金National Natural Science Foundation of China (No.82260134)Natural Science Foundation of Guangxi (No.2023GXNSFAA026118)+1 种基金High-level Talents Research Project of the Affiliated Hospital of Youjiang Medical College for Nationalities (No.R202011702)Guangxi Graduate Education Innovation Project (No.YCSW2023506)。
文摘Objective:To investigate the role of miR-129-5p in regulating HMGB1 expression in pancreatic cancer cell apoptosis.Methods:The untreated pancreatic cancer SW1990 cells were used as the control group.Mimics-NC(empty vector),miR-129-5p mimics,inhibitor-NC(empty vector)and miR-129-5p inhibitor were transfected into SW1990 cells by liposome transfection method as the mimics-NC group,miR-129-5p overexpression group(miR-129-5p mimics group),inhibitor-NC group and miR-129-5p low expression group(miR-129-5p inhibitor group).The binding site of miR-129-5p and HMGB1 was predicted by online target gene prediction website Target genes,and the targeting relationship between miR-129-5p and HMGB1 was verified by dual luciferase gene report experiment.The expression of miR-129-5p in each group was detected by qRT-PCR,and the expression of HMGB1 protein and apoptosis-related proteins Caspase 3 and Bcl-2 by Western blot.Hoechst staining was used to observe the changes of apoptosis.Results:Compared with the mimics-NC group and control group,miR-129-5p mimics transfection significantly up-regulated miR-129-5p level(P<0.01),inhibited HMGB1(P<0.01)and Bcl-2(P<0.05)protein expression,pro-moted Caspase 3 protein expression(P<0.05),and promoted apoptosis;compared with the inhibitor-NC group and control group,miR-129-5p inhibitor transfection significantly down-regulated miR-129-5p level(P<0.05),promoted HMGB1 and Bcl-2 protein expression(all P<0.05),inhibited Caspase 3protein expression(P<0.01),and inhibited apoptosis.The results of dual luciferase reporter gene assay showed that miR-129-5p could inhibit the fluorescence activity of wildtype HMGB1 cells and target the expression of HMGB1.Conclusion:miR-129-5p promotes the apoptosis of pancreatic cancer SW1990 cells by targeting inhibition of HMGB1 expression.
文摘The modulatory role of bcl 2 gene in hepatocellular apoptosis of rats with glycochenodeoxycholate (GCDC) induced obstructive jaundice was investigated. The hepatocytes in normal rats and those with bile duct ligation for 7 days, 14 days and 21 days were isolated and obtained by in situ collagenase perfusion and primary culture. The expression of bcl 2 mRNA in the hepatocytes was detected by RT PCR. Primary culture was performed on the hepatocytes from normal rats and those with bile duct ligation for 14 days. 100 μmol/L GCDC was added to the hepatocytes for incubation for 24 h. The hepatocellular apoptotic ratio was measured by using FCM and hepatocellular apoptosis detected in situ by using TUNEL technique. Results showed that the expression of bcl 2 mRNA was not detectable in the hepatocytes of normal rats by RT PCR technique, while detectable in the hepatocytes of those with bile duct ligation (BDL) for 7, 14 and 21 days. Hepatocellular apoptosis in the BDL group was obviously decreased as compared with normal control group after addition of 100 μmol/L GCDC to the cells for 24 h. It was concluded that the hepatocytes in the BDL rats expressed bcl 2. During obstructive jaundice, expression of bcl 2 from the hepatocytes can inhibit the bile salt induced hepatocellular apoptosis.
文摘In order to investigate the protective effect of hypoxic preconditioning on the cerebral ischemia-reperfusion injury, the expression of Bcl-2 and Bax was detected by using immunohistochemical staining after 3 h cerebral ischemia followed by 1, 6, 12, 24 and 48 h reperfusion respectively in rats treated with or without hypoxic preconditioning before cerebral ischemia. In addition, the apoptosis of neural cells and the behavioral scores for neurological functions recovery were evaluated by TUNEL staining and ＂crawling method＂, respectively. Compared with control group （cerebral ischemia-reperfusion without hypoxic preconditioning）, the expression of Bcl-2 was significantly increased, but that of Bax decreased in the hypoxic preconditioning group （cerebral ischemiareperfusion with hypoxie preconditioning）, both P〈0.05. The pre-treatment with hypoxic preconditioning could reduce the apoptosis of neural cells and promote the neurological function recovery as compared to control group. It was suggested that hypoxic preconditioning may have protective effects on the cerebral ischemia-reperfusion injury by inhibiting the apoptosis of neural cells, increase the expression of Bcl-2 and decrease the expression of Bax.
文摘In order to study the effects of ethyl pyruvate on cardiomyocyte apoptosis following ischemia/reperfusion （I/R） in vitro and the expression of Bcl-2 and Bax proteins, isolated rat hearts were perfused in a Langendorff model. Twenty-four rats were randomly divided into 3 groups （n=8 in each group）： control group was perfused for 120 min. In the I/R group, after 30 min stabilization the injury was induced by 30 min global ischemia followed by 60 min reperfusion. Ethyl pyruvate （EP） group was set up with the same protocol as I/R group except that it was supplied with 2 mmol/L EP 15 rain before ischemia and throughout reperfusion. Myocardial malonaldehyde （MDA） content was measured. Myocardial apoptotic index （AI） was tested by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling （TUNEL） method. The expression of anti-apoptotic protein Bcl-2 and pro-apoptotic protein Bax in cardiac myocytes was detected by immunohistochemistry. As compared with control group, the content of MDA, myocardial AI and the expression of Bcl-2, Bax proteins were increased significantly in I/R group, but the content of MDA, myocardial AI and the expression of Bax protein were decreased obviously and the expression of Bcl-2 protein was up-regulated in EP group （P〈0.05）. These results demonstrate that EP could inhibit apoptosis of cardiac myocytes possibly via alleviating oxidative stress, up-regulating Bcl-2 and down-regulating Bax proteins.
基金supported by a grant from the Foundation of Most Advanced Group of Medical Scientists and Technicians of Shandong Province (2007GG30002014)
文摘BACKGROUND:Many Chinese herbs,especially herbal injections,have been shown to have anti-tumor effects in recent years.However,since most reports focus on the clinical effectiveness of these herbs,their mechanisms of action are not well understood.In this study,we assessed apoptosis in the hepatocellular carcinoma (HCC) cell line HepG2 induced by an injectable extract from the seed of Coix lacryma-jobi (Semen coicis,SC),and monitored the expression of Bcl-2 and caspase-8.METHODS:Injectable SC was applied to HepG2 cells at different concentrations and the cells were collected 12,24 and 48 hours later.5-fluorouracil was used as a positive control group,and fluorescence-activated cell-sorting cytometry was used to measure the apoptosis rate of HepG2 cells and the expression of Bcl-2 and caspase-8 proteins.RESULTS:SC induced apoptosis in HepG2 cells in a concentration and time-dependent manner,and the expression of caspase-8 was elevated and prolonged.However,it did not significantly influence the expression of Bcl-2.CONCLUSION:Injectable SC may induce apoptosis in HCC cells by regulating the expression of caspase-8.
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.
基金Thisprojectwassupported by a grant from the NaturalSciences Foundation of Hubei Province(No.2 0 0 0 J0 5 0 ) .
文摘To observe the effectof ginsenoside Re on cardiomyocyte apoptosis and Bcl- 2 / Bax gene expression after ischemia (30 m in) and reperfusion (6 h) in rats and to elucidate the possible m echanism s of ginsenoside Re on inhibition of cardiom yocyte apoptosis,the ischem ia/ reperfusion heart m odel was established by ligating the left anterior descending branch of coronary artery in Wistar rats.The apoptotic cardiom yocytes were confirmed by transm ission electron m icroscopy and counted by in situ nick end labeling(TU NEL) method and lightm icroscopy.The m RNA and protein expression of Bcl- 2 and Bax genes were studied by in situ hybridization and im munohis- tochemical staining.Mean optical density (OD) value of the positive fields of m RNA and protein expression was quantitatively exam ined by im age analysis system.The results were as follows: (1) The apoptotic cardiomyocytes were found in ischemic fields in the ischem ia/ reperfusion group and weren't observed in the sham- operation group by transmission electron microscopy;(2 ) The num bers of the apoptotic cells were134.4 5± 4 5 .6 1/ field in the ischemia/ reperfusion group,and 90 .6 6± 19.2 2 / field in the ginsenoside Re- treated group.The differences was significant between two groups(P<0 .0 1) ;(3) Gene expression of Bcl- 2 and Bax were increased significantly in the is- chemia/ reperfusion group and ginsenoside Re- treated group when compared with the sham - opera- tion group.There was no significant difference in the gene expression of Bcl- 2 between the gin- senoside Re- treated group and ischemia/ reperfusion group(P>0 .0 5 ) ,but gene expression of Bax was decreased significantly in the ginsenoside Re- treated group as compared with the ischem ia/ reperfusion group(P<0 .0 1) .The ratio of Bcl- 2 / Bax was increased significantly in the ginseno- side Re- treated group when com pared with the ischem ia/ reperfusion group and sham- operation group.These findings suggest that m yocardial ischem ia- reperfusion can induce cardiom yocyte apoptosis,and ginsenoside Re can significantly inhibit cardiom yocyte apoptosis induced by ischemi- a- reperfusion in rats.It is concluded that ginsenoside Re inhibits cardiomyocyte apoptosis by in- hibiting expression of pro- apoptotic Bax gene and raising the ratio of Bcl- 2 / Bax.
文摘To investigate the relationship of bcl-2, p53, proliferating cell nuclear antigen (PCNA) to cell proliferation, apoptosis and pathological parameters, the patterns of cell growth and turnover in renal cell carcinoma (RCC), formalin-fixed and paraffin-embedded tissue blocks from 34 patients with RCC were examined. Cell proliferation activity was detected by PCNA immunostaining and the proliferation index (PI) was expressed as a percentage of the PCNA-positive cells in the tumor cells. Apoptosis was detected by terminal deoxy- nucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and the apoptotic index (AI) was expressed as a percentage of the TUNEL-positive cells in the tumor cells. Expressions of bcl-2 and p53 were assessed immunohistochemically. Our results showed that the PI ranged from 6.0 % to 24.0 % (median 12.3 %) and the AI from 2.0 % to 8.0 % (median 5.4 %) in RCC. The expression of the bcl-2 protein was demonstrated in 15 cases (44.1 %); the expression of the p53 protein, however, was seen in only 3 case. bcl-2 positivity was not associated with PI or AI or any pathological parameters. There were close associations between PI and tumor grade and stage, and a significant relationship between AI and the tumor grade of RCC. Our study suggests that bcl-2 positivity was not associated with PI or AI or any pathological parameters. There are close associations between PI and AI and tumor grade and stage of RCC. Active cell proliferation may be accompanied by frequent apoptosis in RCC.
