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Apoptotic Activity (apoptotic + activity)
Selected AbstractsApoptotic activity in gestational trophoblastic disease correlates with clinical outcome: assessment by the caspase-related M30 CytoDeath antibodyHISTOPATHOLOGY, Issue 3 2001P M Chiu The objective of this study was to assess apoptotic activity in gestational trophoblastic disease (GTD) and its prognostic value in hydatidiform mole (HM). Expression of the specific caspase cleavage site within cytokeratin 18 was assessed immunohistochemically using the monoclonal antibody M30 CytoDeath in 12 spontaneous abortions, 22 partial and 57 complete HM, eight choriocarcinoma (CCA) and 28 normal placentas. The M30 immunoreactivity occurred predominantly in the syncytiotrophoblasts. A significantly higher M30 index in HM and CCA was found when compared with normal placentas and spontaneous abortions (P < 0.001). The M30 index of those HM which spontaneously regressed was significantly higher than those HM which developed persistent disease requiring chemotherapy (P < 0.001). The M30 index correlated with another apoptotic index previously detected by TdT-mediated dUTP nick-end labelling (TUNEL) (P = 0.007) and the proliferation index assessed by the Ki67 antigen (P = 0.034). We conclude that apoptosis is important in the pathogenesis of GTD. Assessment of apoptotic activity in HM by the M30 index may be considered as an alternative prognostic indicator for predicting the clinical behaviour. [source] Apoptotic activity of doxazosin on prostate stroma in vitro is mediated through an autocrine expression of TGF-,1THE PROSTATE, Issue 3 2001Kenneth Y. Ilio Abstract Background Doxazosin, an alpha-adrenergic antagonist, has been shown to induce apoptosis in prostatic stromal cells. The mechanism of this apoptotic action by Doxazosin remains undefined. The present study was carried out to demonstrate that the effect of Doxazosin on apoptosis of prostate stromal cells is mediated through an autocrine action of TGF-,1. Methods Primary cultures of human prostate cells were treated with varying concentrations of Doxazosin (0, 0.1, 1, 10, and 100 ,M) for a period up to 3 days. At the end of the 3-day culture, cell numbers were counted. Apoptosis was assessed by a colorimetric terminal deoxyribonucleotide transferase labeling technique. TGF-,1 was determined by enzyme-linked immunosorbent assay (ELISA). Results Compared to control cultures, cell numbers were significantly decreased as much as 68.4% in cultures treated with 10 ,M of Doxazosin after 3 days incubation, while apoptosis increased by 64.7% in cultures treated with the same concentration of Doxazosin after 24 h. This decrease in cell number was reversed when antibody to TGF-,1 was added to these cultures. Addition of TGF-,1 (0, 1.0, and 10 ng/mL) to the cultures also decreased the cell numbers. Quantitation of TGF-,1 in lysates of cells by ELISA revealed that the cells treated with Doxazosin (10 ,M) produced as much as 62.5% more TGF-,1 than in that of untreated cells. Conclusions These results demonstrate that the apoptotic effect of Doxazosin on human prostatic stromal cells is mediated through an autocrine production of TGF-,1. Prostate 48:131,135, 2001. © 2001 Wiley-Liss, Inc. [source] Characteristics of dengue virus-infected peripheral blood mononuclear cell death that correlates with the severity of illnessMICROBIOLOGY AND IMMUNOLOGY, Issue 8 2009Yanin Jaiyen ABSTRACT The pathogenic mechanism of the severe form of dengue is complicated. Recent reports indicate that apoptotic death of various tissues or organs may be associated with vascular leakage, and ultimately leads to the death of DENV-infected patients. In the present study, we provide additional evidence supporting the detrimental role of apoptosis in DENV infection. A comparison of the rate of apoptosis in PBMCs isolated from patients suffering DF, a mild form of the disease, and the rate in patients with DHF, a life-threatening disease, revealed that PBMCs from DHF patients underwent apoptosis at a significantly higher rate than those suffering from DF alone. This suggests that the severity of natural DENV infection correlates with PBMC apoptosis. In addition, this cell death was induced not only by DENV itself, but also by the apoptotic activities of pro-inflammatory cytokines, such as TNF-,, and IL-1,, that were upregulated in DHF patients. The death of these mononuclear cells that function in an innate immune system may explain the higher viral load in DHF patients than in DF patients. Interestingly, a gene expression profile pattern elucidated that apoptosis occurring during natural DENV infection involved mainly the extrinsic apoptosis pathway, which is mediated via both caspase-dependent and caspase-independent mechanisms. In conclusion, our data highlight the adverse effect of apoptosis induced by DENV and by pro-inflammatory cytokines during natural DENV infection. [source] Mahanine inhibits growth and induces apoptosis in prostate cancer cells through the deactivation of Akt and activation of caspases,THE PROSTATE, Issue 12 2006Swati Sinha Abstract BACKGROUND The present study was undertaken to evaluate anti-proliferative and -apoptotic activities of mahanine, a plant derived carbazole alkaloid, in prostate cancer cells and to determine its molecular mechanism by which it induces apoptotic cell death. METHODS The growth inhibitory and apoptotic inductive effect of mahanine on prostate cancer cells were examined by measuring cell proliferation and BrdU labeling, caspase activity, DNA fragmentation, and Western blot analyses. RESULTS Mahanine inhibited growth of PC3 and LNCaP prostate cancer cells in a dose and time-dependent manner. Mechanistically, mahanine inhibited cell-survival pathway by dephosphorylation of PIP3 dependent kinase 1 (PDK1) thereby deactivation of Akt and downregulation of Bcl-xL. In addition, mahanine activated caspase pathway (caspases 9 and 3) and eventually cleavage of DNA repair enzyme, PARP resulting DNA fragmentation and apoptosis. CONCLUSIONS Mahanine inhibits growth and induces apoptosis in both androgen-responsive, LNCaP and androgen-independent, PC3 cells by targeting cell survival pathway. Prostate © 2006 Wiley-Liss, Inc. [source] Apoptotic activity in gestational trophoblastic disease correlates with clinical outcome: assessment by the caspase-related M30 CytoDeath antibodyHISTOPATHOLOGY, Issue 3 2001P M Chiu The objective of this study was to assess apoptotic activity in gestational trophoblastic disease (GTD) and its prognostic value in hydatidiform mole (HM). Expression of the specific caspase cleavage site within cytokeratin 18 was assessed immunohistochemically using the monoclonal antibody M30 CytoDeath in 12 spontaneous abortions, 22 partial and 57 complete HM, eight choriocarcinoma (CCA) and 28 normal placentas. The M30 immunoreactivity occurred predominantly in the syncytiotrophoblasts. A significantly higher M30 index in HM and CCA was found when compared with normal placentas and spontaneous abortions (P < 0.001). The M30 index of those HM which spontaneously regressed was significantly higher than those HM which developed persistent disease requiring chemotherapy (P < 0.001). The M30 index correlated with another apoptotic index previously detected by TdT-mediated dUTP nick-end labelling (TUNEL) (P = 0.007) and the proliferation index assessed by the Ki67 antigen (P = 0.034). We conclude that apoptosis is important in the pathogenesis of GTD. Assessment of apoptotic activity in HM by the M30 index may be considered as an alternative prognostic indicator for predicting the clinical behaviour. [source] PPAR, and PP2A are involved in the proapoptotic effect of conjugated linoleic acid on human hepatoma cell line SK-HEP-1INTERNATIONAL JOURNAL OF CANCER, Issue 11 2007Giuliana Muzio Abstract Conjugated linoleic acid (CLA), found in dairy products, in beef and lamb has been demonstrated to possess anticancer properties protecting several tissues from developing cancer. Moreover, it has been shown to modulate apoptosis in several cancer cell lines. The aim of this study was to investigate which signaling transduction pathways were modulated in CLA-induced apoptosis in human hepatoma SK-HEP-1 cells. The cells exposed to CLA were evaluated for PPAR,, PP2A, pro-apoptotic proteins Bak, Bad and caspases, and anti-apoptotic proteins Bcl-2 and Bcl-XL. Cells were also treated with okadaic acid, a PP2A inhibitor, or with Wy-14643, a specific PPAR, agonist. The CLA-induced apoptosis was concomitant to the increase of percentage of cells in the S phase, PPAR,, PP2A and pro-apoptotic proteins; simultaneously, antiapoptotic proteins decreased. Inhibition of PP2A prevented apoptosis, and PPAR, agonist showed similar effect as CLA. The increased PP2A could be responsible for the dephosphorylation of Bcl-2 and Bad, permitting apoptotic activity of Bax and Bad. The increase of caspase 8 and 9 suggested that both the intrinsic and extrinsic apoptotic pathways were induced. PP2A was probably increased by PPAR,, since putative PPRE sequences were found in genes encoding its subunits. In conclusion, CLA induces apoptosis in human hepatoma SK-HEP-1 cells, by increasing PPAR,, PP2A and pro-apoptotic proteins. © 2007 Wiley-Liss, Inc. [source] The Trophic Effects of Oestrogen on Male Rat Anterior Pituitary LactotrophsJOURNAL OF NEUROENDOCRINOLOGY, Issue 5 2009L. A. Nolan Rapid but often transient changes in mitotic and apoptotic activity are important components of the pituitary response to changes in the hormonal environment. For example, bilateral adrenalectomy and orchidectomy each result in a wave of increased mitosis lasting approximately 1 week, mediated by the same population of trophically active and, to a large extent, endocrinologically inactive cells. By contrast to these tonic inhibitors of pituitary trophic activity, reports of a progressive increase in lactotroph numbers during pregnancy suggest that oestrogen is a potent and persistent pituitary mitogen. By comparing the amplitude and duration of male rat anterior pituitary mitotic responses to oestrogen treatment, to adrenalectomy, and to a combination of the two, the present study aimed to further clarify the characteristics of the oestrogen-induced trophic response, in particular whether lactotrophs are the predominant cell type involved. Adrenalectomy produced a wave of increased mitotic activity, which resolved within 7 days as expected, whereas oestrogen induced a significant increase in mitotic activity, which was sustained for the 14-day duration of the study. The trophic effects of combining adrenalectomy and oestrogen treatment were not additive in that the statistically insignificant upward trend in mitotic index during the first few days compared to oestrogen treatment alone was entirely abolished by oestrogen pre-treatment. The increase in mitotic activity in lactotrophs induced by oestrogen either with or without adrenalectomy did not result in an increase in the relative size of the prolactin-positive compared to prolactin-negative pituitary parenchymal cell numbers by the end of the study. Despite the marked increase in the lactotroph population that is reported during pregnancy, these data indicate that at least the early (i.e. within 2 weeks) mitotic response to pharmacological doses of oestrogen increases mitotic activity in the lactotroph subpopulation by only 5,8% relative to other cellular subpopulations. Unexpectedly, the mitotic response to oestrogen principally occurs in non-prolactin-containing cells and results in the recruitment, amongst other trophically responsive populations, of the entire subpopulation of prolactin-, adrenocorticotrophic hormone- and luteinising hormone-negative cells that respond mitotically to adrenalectomy. Oestrogen therefore has a previously unrecognised non-cell type-specific trophic effect in the pituitary that obscures the relative expansion of the lactotroph population by inducing concurrent increases in numbers of prolactin-negative cells, the nature of which at least in part remains to be determined. [source] Cytotoxicity and apoptosis enhancement in brain tumor cells upon coadministration of paclitaxel and ceramide in nanoemulsion formulationsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 7 2008Ankita Desai Abstract The objective of this study was to examine augmentation of therapeutic activity in human glioblastoma cells with combination of paclitaxel (PTX) and the apoptotic signaling molecule, C6 -ceramide (CER), when administered in novel oil-in-water nanoemulsions. The nanoemulsions were formulated with pine-nut oil, which has high concentrations of essential polyunsaturated fatty acid (PUFA). Drug-containing nanoemulsions were characterized for particle size, surface charge, and the particle morphology was examined with transmission electron microscopy (TEM). Epi-fluorescent microscopy was used to analyze nanoemulsion-encapsulated rhodamine-labeled PTX and NBD-labeled CER uptake and distribution in U-118 human glioblastoma cells. Cell viability was assessed with the MTS (formazan) assay, while apoptotic activity of PTX and CER was evaluated with caspase-3/7 activation and flow cytometry. Nanoemulsion formulations with the oil droplet size of approximately 200 nm in diameter were prepared with PTX, CER, and combination of the two agents. When administered to U-118 cells, significant enhancement in cytotoxicity was observed with combination of PTX and CER as compared to administration of individual agents. The increase in cytotoxicity correlated with enhancement in apoptotic activity in cells treated with combination of PTX and CER. The results of these studies show that oil-in-water nanoemulsions can be designed with combination therapy for enhancement of cytotoxic effect in brain tumor cells. In addition, PTX and CER can be used together to augment therapeutic activity, especially in aggressive tumor models such as glioblastoma. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:2745,2756, 2008 [source] Erythrodiol, a natural triterpenoid from olives, has antiproliferative and apoptotic activity in HT-29 human adenocarcinoma cellsMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 5 2008M. Emília Juan Abstract Erythrodiol is the precursor of pentacyclic triterpenic acids present in Olea Europaea. Although olive oil and some of its constituents are reported to have anticarcinogenic activities, erythrodiol has not been assessed in its cell biological functions in detail. We therefore determined its effects on cell growth and apoptosis in human colorectal carcinoma HT-29 cells. Proliferation, cytotoxicity, and apoptosis were measured by fluorescence-based techniques. Erythrodiol inhibited cell growth with an EC50 value of 48.8 ± 3.7 ,M without any cytotoxic effects in a concentration range up to 100 ,M. However, exposure of cells for 24 h to 50, 100, and 150 ,M erythrodiol increased caspase-3-like activity by 3.2-, 4.8-, and 5.2-fold over that in control cells. We here demonstrate for the first time that, in colon adenocarcinoma cells, erythrodiol exerts antiproliferative and proapoptotic activity. [source] Prognostic Significance of p53/bcl-2 Co-expression in Patients With Laryngeal Squamous Cell CarcinomaTHE LARYNGOSCOPE, Issue 8 2000Martin C. Jäckel MD Abstract Objective The p53, bcl-2, and bax genes are known to be involved in control of cell cycle progression and regulation of apoptotic cell death. Although they are frequently altered in laryngeal squamous cell carcinoma, their clinical relevance is not yet fully understood. In the present study, individual and combined expressions of these genes were related with patient survival as well as with proliferative and apoptotic activity. Design Retrospective study. Methods Paraffin-embedded tissue sections of 88 laryngeal squamous cell carcinomas that were diagnosed and treated between 1986 and 1996 were investigated for p53, bcl-2, and bax protein expression by immunohistochemistry. Apoptotic cells were visualized using the nick end labeling method. To assess proliferative activity of tumors, mitotic indices were determined. Results Age of patients, advanced disease (stages III and IV), high mitotic activity, positive bcl-2 expression, high level of p53 expression, and p53/bcl-2 co-expression were significantly associated with shortened overall survival in univariate analysis. In multivariate analysis, only age and p53/bcl-2 co-expression had independent prognostic value. Other combinations of genes, i.e., bcl-2-to-bax and p53-to-bax ratios, were not associated with patient outcome. A significant positive correlation was found between apoptotic and mitotic activity. However, protein levels of p53, bcl-2, and bax were unrelated to proliferation and apoptosis of tumor cells. Conclusions The co-expression of p53/bcl-2 was an independent predictor of patient outcome and had a prognostic value superior to both parameters considered separately. The rate of apoptosis mainly counterbalanced proliferative activity but appeared not to be significantly influenced by p53, bcl-2, and bax. [source] New Insights into Mechanisms of Spontaneous Liver Transplant Tolerance: The Role of Foxp3-Expressing CD25+CD4+ Regulatory T CellsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2008W. Li Liver allografts in mice are accepted across MHC barriers without requirement for immunosuppressive therapy. The mechanisms underlying this phenomenon remain largely undefined. In this study, we investigated the role of Foxp3-expressing CD25+CD4+ regulatory T cells (Treg) in the induction of murine liver transplant tolerance. Foxp3+CD25+CD4+ T cells were increased in liver grafts and recipient spleens from day 5 to day 100 posttransplantation, associated with enhanced CTLA4 and TGF-, expression and IL-4 production. Depletion of recipient CD25+CD4+ T cells using anti-CD25 mAb (250 ,g/day) induced acute liver allograft rejection. This was associated with a decreased ratio of Foxp3+ Treg: T effector cells, decreased IL-4 and elevated IL-10 and IL-2 production by graft-infiltrating T cells, and reduced apoptotic activity of graft-infiltrating CD4+ and CD8+ T cells in anti-CD25-mAb-treated recipients. Thus, the data suggest that Foxp3+CD25+CD4+Treg are involved in spontaneous acceptance of liver allografts in mice. The ratio of Treg to T effector cells appears to determine liver transplant outcome. CTLA4, IL-4, TGF-, and apoptosis of graft-infiltrating T cells are also associated with liver transplant tolerance and may contribute, at least in part, to the mechanisms of Treg-mediated immune regulation in this model. [source] Reissner's Fibre Proteins and p73 Variations in the Cerebrospinal Fluid and Subcommissural Organ of Hydrocephalic RatANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2009E. M. Carmona-Calero Summary Reissner's fibre (RF) is formed by the polymerization of the glycoprotein secreted by the subcommissural organ (SCO). The SCO also secretes soluble glycoprotein into the cerebrospinal fluid (CSF); variations in RF and SCO have been reported in hydrocephalus. On the other hand, hydrocephalus and other brain alterations have been described in p73 mutant mice. The p73 belongs to the tumour suppressor p53 protein family and has two isoforms: the TAp73 with apoptotic activity and ,Np73 with anti-apoptotic function. Moreover, the TAp73 isoform is glycosylated and secreted into the CSF. In the present work, we analysed the variations in RF and p73 proteins in the CSF and SCO of spontaneously hydrocephalic rats. Brains from control rats and spontaneously hydrocephalic rats of 12 months of age were used. The SCO sections were immunohistochemically processed with anti-TAp73 and anti-Reissner fibre (AFRU). The spontaneous hydrocephalus presents a decrease in the AFRU immunoreactive material in the SCO and an absence of RF. The anti-TAp73 was also present, slightly decreased, in the hydrocephalic SCO. AFRU and p73 bands were also detected in the CSF by western blot and six AFRU and p73 protein bands of a similar molecular weight were found in the CSF of the control rats. The number of AFRU and p73 bands was lower in the hydrocephalic rats than in the control rats. In conclusion, hydrocephalus produces a decrease in the secretions of the SCO and an absence of RF and a decrease in p73 and RF proteins in the CSF. [source] |