Mechanism of colon cancer cell apoptosis induced by telocinobufagin: role of oxidative stress and apoptosis pathway / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of telocinobufagin on viability and apoptosis of colorectal cancer (CRC) cells and explore the mechanism of telocinobufagin-induced apoptosis.</p><p><b>METHODS</b>MTT assay was performed to detect the viability of CRC cells exposed to telocinobufagin. Nuclear staining with Hoechst 33342 and flow cytometry were used to analyze the cell death of CRC cells. Expressions of proteins related with cell apoptosis and oxidative stress were determined with Western blotting.</p><p><b>RESULTS</b>Telocinobufagin decreased the viability of CRC cells in a time- and dose-dependent manner. The presence of karyopycnosis and apoptotic bodies together with the results of flow cytometry suggested that telocinobufagin induced cell apoptosis to cause cell death. Western blotting showed that telocinobufagin exposure of the cells resulted in upregulated p53 and Bax protein expressions and promoted cleavage of caspase 9 and PARP. Telocinobufagin induced phosphorylation of Bad and PARP cleavage, and suppressed phosphorylation of IKBα and TAK1 and expression of survivin in the cells.</p><p><b>CONCLUSION</b>Telocinobufagin can decrease the viability of CRC cells by inducing cell apoptosis, which involves p53-mediated Bax activation and inhibition of the IAP pathway.</p>

Mitochondrial estrogen receptor β inhibits non-small cell lung cancer cell apoptosis via interaction with Bad / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the molecular mechanisms by which mitochondrial estrogen receptor β (ERβ) suppresses non-small cell lung cancer cell apoptosis induced by apoptotic stimulations.</p><p><b>METHODS</b>The mitochondrial localization of ERβ in non-small cell lung cancer cell lines A549 and 201T was determined using immunofluorescence and Western blotting. The changes of apoptosis of the cells with mitochondrial ERβ overexpression or knockdown in response to cisplatin and STS treatments were assessed, and mitochondrial ERβ interaction with the pro-apoptotic protein Bad was detected using co-immunoprecipitation and Western blotting.</p><p><b>RESULTS</b>ERβ was localized in the mitochondria in A549 and 201T cells. ERβ overexpression significantly reduced while ERβ knockdown increased Bax activation and cell apoptosis induced by cisplatin and STS. Mitochondrial ERβ interaction with pro-apoptotic protein Bad may suppress Bax activation and its translocation to the mitochondria.</p><p><b>CONCLUSION</b>Mitochondrial ERβ can suppress apoptosis of non-small cell lung cancer cells induced by cisplatin or STS through interaction with Bad, suggesting the value of mitochondrial ERβ as a new therapeutic target for treatment of non-small cell lung cancer.</p>

Protein microarray for complex apoptosis monitoring of dysplastic oral keratinocytes in experimental photodynamic therapy

BACKGROUND: Photodynamic therapy is an alternative treatment of muco-cutaneous tumors that uses a light source able to photoactivate a chemical compound that acts as a photosensitizer. The phthalocyanines append to a wide chemical class that encompasses a large range of compounds; out of them aluminium-substituted disulphonated phthalocyanine possesses a good photosensitizing potential. RESULTS: The destructive effects of PDT with aluminium-substituted disulphonated phthalocyanine are achieved by induction of apoptosis in tumoral cells as assessed by flow cytometry analysis. Using protein microarray we evaluate the possible molecular pathways by which photodynamic therapy activates apoptosis in dysplastic oral keratinocytes cells, leading to the tumoral cells destruction. Among assessed analytes, Bcl-2, P70S6K kinase, Raf-1 and Bad proteins represent the apoptosis related biomolecules that showed expression variations with the greatest amplitude. CONCLUSIONS: Up to date, the intimate molecular apoptotic mechanisms activated by photodynamic therapy with this type of phthalocyanine in dysplastic human oral keratinocytes are not completely elucidated. With protein microarray as high-throughput proteomic approach a better understanding of the manner in which photodynamic therapy leads to tumoral cell destruction can be obtained, by depicting apoptotic molecules that can be potentially triggered in future anti-tumoral therapies.

Transactivation of bad by vorinostat-induced acetylated p53 enhances doxorubicin-induced cytotoxicity in cervical cancer cells

Vorinostat (VOR) has been reported to enhance the cytotoxic effects of doxorubicin (DOX) with fewer side effects because of the lower DOX dosage in breast cancer cells. In this study, we investigated the novel mechanism underlying the synergistic cytotoxic effects of VOR and DOX co-treatment in cervical cancer cells HeLa, CaSki and SiHa cells. Co-treatment with VOR and DOX at marginal doses led to the induction of apoptosis through caspase-3 activation, poly (ADP-ribose) polymerase cleavage and DNA micronuclei. Notably, the synergistic growth inhibition induced by the co-treatment was attributed to the upregulation of the pro-apoptotic protein Bad, as the silencing of Bad expression using small interfering RNA (siRNA) abolished the phenomenon. As siRNA against p53 did not result in an increase in acetylated p53 and the consequent upregulation of Bad, the observed Bad upregulation was mediated by acetylated p53. Moreover, a chromatin immunoprecipitation analysis showed that the co-treatment of HeLa cells with VOR and DOX increased the recruitment of acetylated p53 to the bad promoter, with consequent bad transactivation. Conversely, C33A cervical cancer cells containing mutant p53 co-treated with VOR and DOX did not exhibit Bad upregulation, acetylated p53 induction or consequent synergistic growth inhibition. Together, the synergistic growth inhibition of cervical cancer cell lines induced by co-treatment with VOR and DOX can be attributed to the upregulation of Bad, which is induced by acetylated p53. These results show for the first time that the acetylation of p53, rather than histones, is a mechanism for the synergistic growth inhibition induced by VOR and DOX co-treatments.

The study of the protective effect and its mechanism of Edaravone to neurons with hydrogen peroxide stimulated / 中华外科杂志

<p><b>OBJECTIVES</b>To prove the protective effect of Edaravone to neurons and to study the particular mechanism.</p><p><b>METHODS</b>Neurons were collected from 18-day fetal rat brains and a culture of almost pure neurons was obtained after 14-day culture, then the cells were randomly assigned to one of the three groups: control group, hydrogen peroxide (H₂O₂)-treated group, and Edaravone-treated group. In H₂O₂-treated group, 300 µmol/L H₂O₂ was added to the medium, followed by returning to the normal culture for the presupposition of time. In Edaravone-treated group, 500 µmol/L Edaravone was prophylactically added to the medium for 30 minutes before the insult. Morphology of mitochondria was visualized by transmission electron microscopy. The rate of apoptotic cells was detected by flow cytometry analysis. The relationships between the proteins and the key proteins expressions were observed by immunoprecipitation and immunoblotting.</p><p><b>RESULTS</b>Compared to the Edaravone-treated group, mitochondria in H₂O₂-treated group displayed more vesicular matrix compartments at the same time. Percentage of apoptotic cells in H₂O₂-treated group after 0.5, 2, 6 and 12 h were 14.40% ± 1.23%, 45.50% ± 2.81%, 56.40% ± 3.53%, 62.50% ± 4.23%, which were higher than control group (F = 274.8, P < 0.01). Edaravone-treated group were 0.90% ± 0.07%, 1.10% ± 0.08%, 3.50% ± 1.90%, 12.60% ± 1.10%, which were lower than H₂O₂-treated group (F = 362.7, P < 0.01). After H₂O₂ stimulation for 0.5 h in H₂O₂-treated group, the levels of p-JNK (Thr183/Tyr185) and cytochrome c in cytosol and BAX in heavy membrane were increased significantly at 0.5 h, reaching a peak at 12 h after stimulation, In addition, the expressions of p-BAD, BAX, BAD and 14-3-3 of cytoplasm decreased, however, these changes were inhibited in the Edaravone-treated group.</p><p><b>CONCLUSIONS</b>As a free radical scavenger, the Edaravone could protect neurons by inhibiting the activity of JNK, the disassociation of BAD from 14-3-3 and the translocation of BAX from the cytosol to mitochondria.</p>

Growth Inhibition of Hepatocellular Carcinoma Huh7 Cells by Lactobacillus casei Extract

PURPOSE: Lactobacillus casei (L. casei) is known to exert anti-proliferation effects on many types of cancer cells. However, the effect of L. casei on liver cancer has not been reported. Accordingly, the aim of this study was to determine the anti-cancer effect of L. casei extract on Huh7 cells. MATERIALS AND METHODS: L. casei ATCC393 extract was prepared and purified. After the treatment of L. casei extract on Huh7 cells, cell viability, cell cycle arrest and cell death were analyzed by flow cytometry. The expression levels of tumor necrosis factor-alpha receptor 1 (TNFR1) and death receptor 3 (DR3) mRNA related with extrinsic apoptosis were assessed by reverse transcription polymerase chain reaction. Additionally, P21 and P27 cell cycle proteins as well as Caspase-3, -8, -9, phospho-Bad and Bcl-2 apoptosis proteins were analyzed by western blot analysis. To determine the effect of L. casei extract on cancer stem-like cells, we analyzed changes in side population fraction through flow cytometry. RESULTS: The cell viability of Huh7 cells treated with L. casei extract was decreased by 77%, potentially owing to increases in the rates of Huh7 cells arrested in the G2/M phase (3% increase) and that underwent apoptosis (6% increase). The expression levels of TNFR1 and DR3 mRNA, as well as P21 and P27 cell cycle proteins, were increased. Meanwhile, the expressions of caspase-8, -9, phospho-Bad and Bcl-2 proteins decreased. However, in the case of side population cells, no remarkable changes were observed. CONCLUSION: L. casei extract exerts a potent anti-tumor effect on the viability of liver cancer cells, although not on cancer stem-like cells.

Tounongsan extract induces apoptosis in cultured Raji cells / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of Tounongsan () extract (TNSE) on proliferation and apoptosis of the human lymphoma cell line Raji and its possible mechanism of action.</p><p><b>METHODS</b>The viability of TNSE-treated Raji cells was measured by a 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Cell apoptosis was determined by flow cytometry. The molecular mechanisms of TNSE-mediated apoptosis were further investigated by reverse transcription-polymerase chain reaction (RT-PCR) analysis of the mRNA expression of nuclear factor κB (NF-κB), Bcl-xL, Bcl-2-associated death promoter (Bad), caspase-9 and caspase-3. Western blotting was used to detect the protein expressions of NF-κB, Bad, cleaved caspase-9 and cleaved caspase-3.</p><p><b>RESULTS</b>TNSE inhibited Raji cell proliferation in dose- and time-dependent manners. After 48-h treatment with various concentrations of TNSE (125, 250 and 500 μg/mL), the apoptosis rates of Raji cell were 12.23%±1.98% (P<0.05), 20.97%±3.96% (P<0.01) and 30.4%±4.87% (P<0.01), respectively, compared with those of the control (6.02%±1.01%). RT-PCR demonstrated that NF-κB mRNA expression was significantly downregulated in Raji cells treated with 250 μg/mL TNSE for 48 h (P<0.05), while Bad, caspase-9 and caspase-3 mRNA levels were upregulated (P<0.05). Moreover, TNSE treatment resulted in downregulation of NF-κB protein expression and strikingly upregulated protein expressions of Bad, cleaved caspase-9, cleaved caspase-3 in a dose-dependent manner, as determined by Western blot.</p><p><b>CONCLUSION</b>TNSE exhibits significant anti-proliferative and apoptotic effects in Raji cells, which may be involved in regulation of NF-κB and Bad, and activation of caspase-9 and caspase-3.</p>

Capsaicin-Induced Apoptosis of FaDu Human Pharyngeal Squamous Carcinoma Cells

PURPOSE: To investigate the anti-tumor effect of capsaicin on human pharyngeal squamous carcinoma cells (FaDu). MATERIALS AND METHODS: The expression of apoptosis/cell cycle-related proteins (or genes) was examined by reverse transcriptase-polymerase chain reaction, western blotting and ELISA methods, while the apoptotic cell population, cell morphology and DNA fragmentation levels were assessed using flow cytometry, fluorescence microscopy and agarose gel electrophoresis. RESULTS: Capsaicin was found to inhibit the growth and proliferation of FaDu cells in a dose- and time-dependent manner. Apoptotic cell death was confirmed by observing increases in nuclear condensation, nuclear DNA fragmentation and sub-G1 DNA content. The observed increase in cytosolic cytochrome c, activation of caspase 3 and PARP (p85) levels following capsaicin treatment indicated that the apoptotic response was mitochondrial pathway-dependent. Gene/protein expression analysis of Bcl-2, Bad and Bax further revealed decreased anti-apoptotic Bcl-2 protein and increased pro-apoptotic Bad/Bax expression. Furthermore, capsaicin suppressed the cell cycle progression at the G1/S phase in FaDu cells by decreasing the expression of the regulators of cyclin B1 and D1, as well as cyclin-dependent protein kinases cdk-1, cdk-2 and cdk-4. CONCLUSION: Our current data show that capsaicin induces apoptosis in FaDu cells and this response is associated with mitochondrial pathways, possibly by mediating cell cycle arrest at G1/S.

Honokiol-induced apoptosis of human non-Hodgkin lymphoma Raji cells and its possible mechanism / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the apoptosis-inducing effect of honokiol on human non-Hodgkin lymphoma Raji cells and the possible mechanism.</p><p><b>METHODS</b>Raji cells were treated with different concentrations of honokiol, and the proliferation of the cells was detected using MTT assay. Flow cytometry was employed to analyze the cell cycle changes and apoptosis of honokiol-treated cells. Caspase 8 activity in the cells was measured by caspase 8 kit, and RT-PCR was used to detect the expression of apoptosis-related genes Bcl-2, Bad, and Bax.</p><p><b>RESULTS</b>Honokiol significantly inhibited the growth of Raji cells in a time- and dose-dependent manner, with IC(50) concentration of 17.53, 12.61, and 7.4 µg/ml at 12, 24, 48 h, respectively. Flow cytometry revealed cell cycle arrest at G0/G1 phase following honokiol treatment. The apoptosis rates of Raji cells treated with 7.5 and 15 µg/ml honokiol were significantly higher than that of the control cells [(18.24∓2.53)%, (28.44∓2.48)% vs (4.84∓1.15)%, P<0.01]. Caspase 8 activity in Raji cells was significantly enhanced by honokiol (P<0.05). The mRNA expression of the apoptosis-promoting gene Bad was significantly increased following honokiol treatment (P<0.01), while the expressions of Bcl-2 and Bax remained unchanged.</p><p><b>CONCLUSION</b>Honokiol can induce apoptosis in Raji cells possibly in relation to enhancement of caspase 8 activity and Bad gene expression.</p>

Effect of valsartan and carnitine on cardiomyocyte Calpain-1 and Bcl-xl expressions of dogs with chronic alcohol intake-induced cardiomyopathy / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the effects of valsartan and carnitine on cardiomyocyte Calpain-1 and Bcl-xl expressions of dogs with chronic alcohol intake-induced cardiomyopathy.</p><p><b>METHODS</b>Dogs were randomly assigned into 4 groups (n = 7 each): (1) alcohol fed (free access to 5%, 1(st) week; 10% 2(nd) week; 500 ml 25% bolus plus free access to 5% from 3 to 24 weeks, A); (2) alcohol + valsartan (5 mg×kg(-1)×d(-1), B); (3) alcohol + carnitine (300 mg×kg(-1)×d(-1), C); (4) Control (D). After six months, all animals were assessed for left ventricular (LV) function by echocardiography. The Bad and Bcl-xl protein expressions were evaluated by immunohistochemistry. The expression of Calpain-1 protein was determined with Western blot. Myocardial morphology was quantified on HE stained slices and under electron microscopy. The terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) was performed for apoptosis analysis.</p><p><b>RESULTS</b>Compared with group D, LVEDD and LVESD were significantly increased while EF and FS significantly decreased in group A. In alcohol fed group, expressions of Bad and Calpain-1 protein were significantly increased while Bcl-xl protein expression was downregulated, all changes could be significantly attenuated by intervention with valsartan and carnitine (all P < 0.05).</p><p><b>CONCLUSION</b>These data suggest that alcohol could promote cardiac myocyte apoptosis, reduce cardiac function and aggravate myocardial remodeling which valsartan and carnitine could reduce alcoholic cardiomyopathy by downregulating Calpain-1 and Bad protein expression and upregulating expression of Bcl-xl protein.</p>

Apoptosis inducing effect of tanshinone II(A) on human nasopharyngeal carcinoma CNE cells / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate anticancer effect and potential mechanism of tanshinone II(A) (Tan II(A)) on human nasopharyngeal carcinoma cell line CNE cells.</p><p><b>METHOD</b>Antiproliferative effect of Tan II(A) on CNE cells was evaluated by morphological examination, cell growth curves, colonial assay and MTT assay. Apoptosis detection was carried out using Hoechest 33258 and PI double-dyeing method. Intracellular Ca2+ concentration and mitochondria membrane potential were detected by fluorospectrophotometer. Bad and MT-1A transcript analysis in CNE cells was analyzed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR).</p><p><b>RESULT</b>Tan II(A) could inhibit CNE cells proliferation in dose- and time-dependent manner. 50% inhibiting concentration of Tan II(A) on CNE cells in 24, 48, 72 h was 45.7, 24.8, 3.3 mg x L(-2), respectively. Typical apoptotic morphology such as chromatin aggregation was observed in CNE cells with Tan II(A) treated for 24 h, and the apoptotic inducing effect was in a dose-dependent manner. After treated with Tan II(A), intracellular Ca2+ concentration of CNE cells was increased, mitochondria membrane potential of the cells was decreased, relative mRNA level of Bad and MT-1A was up-regulated.</p><p><b>CONCLUSION</b>Tan II(A) had anticancer effect on CNE cells through apoptosis via calcineurin-dependent pathway and MT-1A downregulation.</p>

Transplante experimental, subcutâneo e intraperitoneal, de ovário em suínos: estudo histomorfométrico e imunoistoquímico / Experimental transplantation, subcutaneous and intraperitoneal, ovary in pigs: immunohistochemical and histomorphometric study

O transplante autólogo de tecido ovariano constitui alternativa relevante na preservação da fertilidade e da função hormonal ovariana em mulheres sujeitas à falência ovariana prematura e infertilidade, por causas malignas, tratamentos adjuvantes ou cirurgias. É a única opção para crianças, fase pré-puberal e para mulheres que não podem retardar a quimioterapia ou não podem ser submetidas à estimulação do ciclo. O transplante ovariano autólogo pode ser, quanto ao local de reimplantação, ortotópico ou heterotópico e, quanto à conservação, a fresco ou após o período de criopreservação. As várias etapas envolvidas neste transplante são estudadas mundialmente na atualidade, como a retirada e preservação do tecido ovariano, as técnicas de criopreservação, o local apropriado para o reimplante e as possibilidades de redução da perda folicular. A avaliação da apoptose - morte celular programada - é útil na avaliação da rejeição e viabilidade dos enxertos de transplantes estabelecidos na prática clínica, tanto autólogos como heterólogos. Com o intuito de utilizar animais de maior porte, conseguir seguimento de médio prazo e realizar os procedimentos cirúrgicos por via laparoscópica, padrão ouro em humanos, o presente estudo utilizou como modelo experimental fêmeas suínas, em idade reprodutiva, da raça Minipig. Este projeto teve como propósito avaliar a influência da criopreservação e do local de implante na qualidade e na viabilidade do transplante autólogo de ovário, a fresco e após criopreservação, no tecido celular subcutâneo e na região intraperitoneal peri-infundibular. Foram avaliados a quantidade e a densidade folicular dos implantes e os aspectos morfológicos e histomorfométricos, bem como a apoptose, por meio da imunoexpressão de proteínas proapoptóticas- Bax e antiapoptóticas-Bcl-2, além da Caspase 3-clivada, fase final das vias extrínseca e intrínseca dos mecanismos de apoptose.Quarenta animais foram divididos em cinco grupos: Controle com ooforectomia...

Autotransplantation of ovarian tissue is an important alternative to preserve fertility and hormonal ovarian function in women undergoing ovarian failure and premature infertilidade, because of cancer or surgery. It is the only option for infants, pre-pubertal patients and for women who can not delay chemotherapy or not may be subjected to stimulation of the cycle. The various steps involved in the transplant are studied worldwide today, as the removal and preservation of ovarian tissue, the techniques of cryopreservation, the appropriate site and mechanisms to reduce follicular loss. Assessment of apoptosis - programmed cell death-is useful in the study of the viability of the grafts and rejection of transplants established in clinical practice, both autologous and heterologous. In order to use larger animals, getting following medium term (over 21 days) and to perform surgical procedures by laparoscopy (gold standard in humans), this study used an experimental model sows, reproductive age, Minipig race. This project aims to evaluate the influence of cryopreservation and implantation site of the quality and viability of ovarian autografts, fresh and after cryopreservation, at subcutaneous site and at intraperitoneal site. We analyzed the quantity and density of follicular implants and the morphological and histomorphometric as well as apoptosis, by proteins immunoexpression antiapoptotic and proapoptotic. Forty animals were divided into five groups: Control with oophorectomy (Group I), oophorectomy and fresh transplantation to subcutaneous site (Group II), oophorectomy and fresh transplantation to intraperitoneal site (Group III), oophorectomy and transplantation of cryopreserved ovarian tissue to subcutaneous site (Group IV) and oophorectomy and transplantation of cryopreserved ovarian tissue to intraperitoneal site (Group V). We concluded that the autologous ovarian transplantation was feasible in the technical proposals, in subcutaneous and...

Effect of tissue factor pathway inhibitor on apoptosis of rat mesangial cells and Fas and bcl-2 expression / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the biological impact and mechanism of recombinant tissue factor pathway inhibitor (rTFPI) on apoptosis of rat kidney mesangial cells (MsC).</p><p><b>METHODS</b>TFPI expression in human glomerular minor lesion (GML), mesangial proliferative glomerulonephritis (MPGN) and cultured rat MsC was detected using immunohistochemistry and immunofluorescence, respectively. Rat MsC were incubated with rTFPI and its variant peptides. Morphological changes of apoptosis were investigated by Hoechst 33258 and the apoptotic rate was assessed by flow cytometry. DNA fragmentation and effect of rTFPI on expression of caspase-3, Fas and bcl-2 were studied using gel electrophoresis and Western blot respectively.</p><p><b>RESULTS</b>The expression of TFPI in MPGN was higher than that in GML. TFPI was expressed in cultured rat mesangial cells. Apoptosis of MsC was induced by rTFPI, especially by its C-termianl, in a dose- and time-dependent manner. Apoptosis ratios of MsC treated with rTFPI were 2.1, 3.0 and 4.9 times more than control, respectively. Expression of gene caspase-3 and Fas was up-regulated in a dose-dependent manner wherease bcl-2 expression did not show any changes.</p><p><b>CONCLUSION</b>rTFPI induces apoptosis in cultured rat mesangial cells by its C-terminal possibly via Fas/FasL pathway.</p>

Repeated electroconvulsive seizure induces c-Myc down-regulation and Bad inactivation in the rat frontal cortex

Repeated electroconvulsive seizure (ECS), a model for electroconvulsive therapy (ECT), exerts neuroprotective and proliferative effects in the brain. This trophic action of ECS requires inhibition of apoptotic activity, in addition to activation of survival signals. c-Myc plays an important role in apoptosis of neurons, in cooperation with the Bcl-2 family proteins, and its activity and stability are regulated by phosphorylation and ubiquitination. We examined c-Myc and related proteins responsible for apoptosis after repeated ECS. In the rat frontal cortex, repeated ECS for 10 days reduced the total amount of c-Myc, while increasing phosphorylation of c-Myc at Thr58, which reportedly induces degradation of c-Myc. As expected, ubiquitination of both phosphorylated and total c-Myc increased after 10 days ECS, suggesting that ECS may reduce c-Myc protein level via ubiquitination-proteasomal degradation. Bcl-2 family proteins, caspase, and poly(ADP-ribose) polymerase (PARP) were investigated to determine the consequence of down-regulating c-Myc. Protein levels of Bcl-2, Bcl-X(L), Bax, and Bad showed no change, and cleavage of caspase-3 and PARP were not induced. However, phosphorylation of Bad at Ser-155 and binding of Bad to 14-3-3 increased without binding to Bcl-X(L) after repeated ECS, implying that repeated ECS sequesters apoptotic Bad and frees pro-survival Bcl-X(L). Taken together, c-Myc down-regulation via ubiquitination-proteasomal degradation and Bad inactivation by binding to 14-3-3 may be anti-apoptotic mechanisms elicited by repeated ECS in the rat frontal cortex. This finding further supports the trophic effect of ECS blocking apoptosis as a possible therapeutic effect of ECT.

Effects of microcystins on expression of apoptosis-associated hepatocyte genes / 中华预防医学杂志

<p><b>OBJECTIVE</b>To deeply explore the effects of microcystins (MC-LR) on Bax and Bcl-2 during the course of MC-LR promoting liver tumor.</p><p><b>METHODS</b>applied to set up the animal model, and the effect of MC-LR promoting liver tumor was evaluated by the Albertgamma-GT methods. And then, the immunohistochemical technique, RT-PCR and image analysis were used to study the expression of the Bcl-2 and Bax during the course of promoting tumor.</p><p><b>RESULTS</b>(1) MC-LR might enhance the positive reaction rate of GGT. The positive reaction rate of GGT in DEN + pure toxin group was 100%, it was significantly higher than the DEN control group 22.22% (P < 0.05). (2) The intension and areas of the protein expression of Bcl-2 in DEN + pure toxin group were 0.0977 and 0.0315, and in DEN control group were 0.0460 and 0.0205, respectively. The expression level of Bcl-2 protein in DEN + pure toxin group were significantly higher than in DEN control group (P < 0.05). Simultaneously, the protein expression of Bax was significantly decreased by MC-LR (P < 0.05). The intension and areas of the expression of Bax in DEN + pure toxin group were 0.0283 and 0.0073, and in DEN control group were 0.0655 and 0.0244 respectively. (3) The mRNA expression of Bcl-2 was significantly increased by MC-LR. The intension of Bcl-2 mRNA expression in DEN + pure toxin group was 2.244, being significantly higher than in the other groups (P < 0.05). However, the mRNA expression of Bax showed no significant difference between DEN + pure toxin and the other groups.</p><p><b>CONCLUSION</b>The expression change of Bcl-2 and Bax should possibly play an important role in the course of MC-LR promoting liver tumor.</p>

Apoptosis induced by DNA primase inhibitor 3,3'-diethyl-9-methylthia-carbocyanine iodide in human leukemia HL-60 cells / 药学学报

<p><b>AIM</b>To investigate apoptosis induced by 3,3'-diethyl-9-methylthia-carbocyanine iodide (DMTCCI), an inhibitor of DNA primase found in our previous study, and the mechanism of DMTCCI in human myelogenous leukemia HL-60 cells.</p><p><b>METHODS</b>HL-60 cells were cultured in RPMI-1640 medium and treated with different concentrations of DMTCCI. MTT assay was used to detect growth inhibition. Flow cytometry and DNA ladders were used to detect apoptosis. Western blotting was used to observe the expression of survivin, Bcl-xL, Bad, Bax, Bcl-2, caspase-9, caspase-3, caspase-6, PARP, DFF45 and lamin B protein. Caspase-3 activity was measured by ApoAlert Caspase-3 Assay Kit.</p><p><b>RESULTS</b>DMTCCI inhibited proliferation of human leukemia HL-60 cells with IC50 value of 0.24 micromol x L(-1). The results of flow cytometry and DNA ladders showed that DMTCCI could induce apoptosis of HL-60 cells. The expression levels of protein survivin and Bcl-xL were down-regulated, Bad and Bax were up-regulated, while Bcl-2 protein had no change in response to DMTCCI treatment in HL-60 cells. Treatment of HL-60 cells with DMTCCI induced the proteolytic cleavage of caspase-9, caspase-3, caspase-6, PARP, DFF45 and lamin B protein. Caspase-3 activity apparently increased at 3 h and reached a peak at 12 h after exposure to 1 micromol x L(-1) of DMTCCI in HL-60 cells.</p><p><b>CONCLUSION</b>DMTCCI inhibited proliferation and induced apoptosis of human leukemia HL-60 cells. Bcl-2 family proteins, survivin and caspases family proteins might play a role in the apoptosis process induced by DMTCCI.</p>

zVAD-fmk, unlike BocD-fmk, does not inhibit caspase-6 acting on 14-3-3/Bad pathway in apoptosis of p815 mastocytoma cells

In a preliminary study, we found that benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone (zVAD- fmk), unlike Boc-aspartyl(OMe)-fluoromethylketone (BocD-fmk), at usual dosage could not prevent genistein-induced apoptosis of p815 mastocytoma cells. This study was undertaken to reveal the mechanism underlying the incapability of zVAD-fmk in preventing this type of apoptosis. We observed that 14-3-3 protein level was reduced in genistein-treated cells and that BocD-fmk but not zVAD-fmk prevented the reduction of 14-3-3 protein level and the release of Bad from 14-3-3. We also demonstrated that truncated Bad to Bcl-xL interaction in genistein- treated cells was prevented by BocD-fmk but not by zVAD-fmk treatment. Our data indicate that BocD- fmk, compared to zVAD-fmk, has a certain preference for inhibiting 14-3-3/Bad signalling pathway. We also elucidated that this differential efficacy of BocD-fmk and zVAD-fmk resulted from the different effect in inhibiting caspase-6 and that co-treatment of zVAD-fmk and caspase-6 specific inhibitor substantially prevented genistein-induced apoptosis. Our data shows that caspase-6 plays a role on Bad/14-3-3 pathway in genistein-induced apoptosis of p815 cells, and that the usual dose of zVAD-fmk, in contrast to BocD-fmk, did not prevent caspase-6 acting on 14-3-3/Bad-mediated event.

Changes of retinal ganglion cells and expression of Bad after optic nerve crush in rats / 法医学杂志

OBJECTIVE@#To observe the change of retinal ganglion cells (RGCs)and the expression of Bad after optic nerve injury, so as to study the changes of optic function level on morphology and molecular.@*METHODS@#The experimental models of optic nerve crush were established in fifty Wistar rats. At the different time after injuries (from one to twenty-eight day), the changes of RGCs were observed under microscope. Immunohistochemiscal technique and computer image analysis methods were performed to observe the changes of Bad in RGCs in rats.@*RESULTS@#The number of RGCs was reduced significantly according to partial lesion of optic nerve crush. An initial loss of RGCs densities was accelerated in one week after nerve crush, two weeks later the trend mitigated. After four weeks, no obvious change were observed. The expression of Bad increased in 3 days, reached peak in 5 days, and declined one week later. No obvious changes were observed after two weeks.@*CONCLUSION@#The expression of Bad lead to the loss of RGCs following optic nerve crush. This is the important reason of loss optic function. The identification on optic nerve injuries should be done at least four weeks later.

Dephosphorelation of Bad and upregulation of Bcl-2 in hippocampus of rats following limbic seizure induced by kainic acid injection into amygdaloid nucleus / 生理学报

The purpose of the present study was to explore the seizure-induced changes in Bad (Bcl-2-associated death protein), 14-3-3, phosphoBad, Bcl-2 and Bcl-XL expression in the rat model of focal limbic seizure. Unilateral intra-amygdaloid injection of kainic acid (KA) was made to induce seizure. Electroencephalogram (EEG) and regional cerebral flow (r-CBF) were monitored continuously. Diazepam (30 mg/kg) was administered to terminate the seizure. The apoptotic and surviving neurons in the hippocampus were observed by terminal deoxynucleotidyl transferrase-mediated dUTP nick end labeling (TUNEL) and cresyl violet staining, the expression of Bad, 14-3-3, phosphoBad, Bcl-2 and Bcl-XL were detected with immunofluorescence, Western blot and immunoprecipitation. The results showed that TUNEL-positive neurons appeared at 8 h and reached maximum at 24 h following seizure cessation within the ipsilateral CA3 subfield of the hippocampus. Seizure induced the dephosphorylation of Bad and the dissociation of Bad from its chaperone protein 14-3-3 and subsequent dimerization of Bad with Bcl-XL. The expression of phosphoBad decreased and Bcl-2 increased. There was little change in r-CBF after the seizure. These results suggest that seizure leads to a dephosphorylation of Bad and an upregulation of Bcl-2. Dephosphorylation of Bad may be injurious while the upregulation of Bcl-2 may be protective to the brain damage induced by seizures, but not related with r-CBF.

The inhibition pathway of the EBV-immortalized cells in children with infectious mononucleosis / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the inhibition pathway of the EBV-immortalized cells (CD23(+)) in children with infectious mononucleosis (IM) caused by Epstein-Barr virus.</p><p><b>METHODS</b>The expressions of CD23, CD19, CD95, Bcl-2 and the co-expressions of CD23CD95, CD19CD23 on peripheral blood mononuclear cell (PBMC) were analyzed by flow cytometry (FCM) during acute phase, early convalescent phase and convalescent phase of 34 EBV-IM children and compared with that of 24 healthy donors.</p><p><b>RESULTS</b>(1) The levels of CD23(+) and CD23(+)CD19(+) cells decreased and CD95(+), CD95(+)CD23(+), Bcl-2(+) cells increased markedly in IM patients in acute phase [CD95(+) cells (19.43 +/- 8.46)%; CD95(+)CD23(+) cells (1.81 +/- 1.71)%; Bcl-2(+) cells (23.41 +/- 26.47)%] and early convalescent phase [CD95(+) cells (12.94 +/- 5.05)%; CD95(+)CD23(+) (1.05 +/- 1.20)%; Bcl-2(+) cells (10.54 +/- 9.68)%], as compared with those of healthy controls [CD95(+) cells (10.39 +/- 2.90)%; CD95(+)CD23(+) cells (0.50 +/- 0.46)%; Bcl-2(+) cells (7.25 +/- 2.88)%]. The earlier the course of IM, the more abnormal the expressive levels. All the abnormal results returned to normal in convalescent phase. (2) Positive relationships were observed between the expressions of CD95(+)CD23(+) cells and that of CD23(+) cells, CD23(+)CD19(+) cells during acute and early convalescent phase, the expressions of Bcl-2(+), CD3(+) cells and CD23(+), CD23(+)CD19(+) cells during acute phase, the expressions of CD95(+)CD23(+) cells and Bcl-2(+) cells during acute phase, and the expressions of CD95(+)CD23(+) cells and CD95(+) cells during convalescent phase.</p><p><b>CONCLUSION</b>The results indicate that CD95L-CD95 mediated apoptosis plays an important role in eliminating EBV-immortalized cells, which is counteracted partly by Bcl-2.</p>