Modulation of human Th17 cell responses through complement receptor 3 (CD11 b/CD18) ligation on monocyte-derived dendritic cells.

PubMed

Nowatzky, Johannes; Manches, Olivier; Khan, Shaukat Ali; Godefroy, Emmanuelle; Bhardwaj, Nina

2018-06-13

Apoptotic cell receptors contribute to the induction of tolerance by modulating dendritic cell function following the uptake of apoptotic cells or microparticles. Dendritic cells that have bound or ingested apoptotic cells produce only low amounts of pro-inflammatory cytokines and fail to prime effector T cell responses. Specifically, ligation of the apoptotic cell receptor CR3 (CD11 b/CD18) on human monocyte-derived dendritic cells (moDC) down-modates proinflammatory cytokine secretion, but the consequences for human Th17 cell homeostasis and effector responses remain unknown. Here, we aimed to establish whether CD11b-ligated moDC modulate Th17 cell effector reponses to assess their potential for future use in moDC-based suppressive immunotherapy. We generated a bead-based surrogate system to target CD11b on monocyte-derived human dendritic cells and examined the effects of CD11b ligation on Th17-skewing cytokine secretion, priming, expansion and functional plasticity in DC/T cell co-culture systems at the poly- and monoclonal level. We show that Th17 cell expansion within the human memory CD4 + T cell compartment was efficiently constricted by targeting the CD11b receptor on moDC. This tolerogenic capacity was primarily dependent on cytokine skewing. Furthermore, ligation of CD11b on healthy homozygous carriers of the rs11143679 (ITGAM) variant - a strong genetic susceptibility marker for human systemic lupus erythematosus - also down-modulated the secretion of Th17-skewing cytokines. Overall, our findings underline the potential of targeted CD11b ligation on human dendritic cells for the engineering of suppressive immunotherapy for Th17-related autoimmune disorders. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hyperforin Suppresses Tumor Growth and NF-κB-mediated Anti-apoptotic and Invasive Potential of Non-small Cell Lung Cancer.

PubMed

Chen, Wei-Ting; Chen, Ying-Kai; Lin, Song-Shei; Hsu, Fei-Ting

2018-04-01

Previous studies have indicated that hyperforin inhibits tumor growth of hepatocellular carcinoma. However, the anticancer effects of hyperforin in non-small cell lung cancer (NSCLC) are ambiguous. The aim of the present study was to investigate the anticancer effect of hyperforin in NSCLC. NSCLC CL1-5-F4 cells were treated with different concentrations of hyperforin or NF-κB inhibitor (QNZ) for different time periods. Change of cell viability, NF-κB activation, apoptotic signaling pathways, expression of anti-apoptotic proteins, and cell invasion were detected using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, NF-κB reporter gene assay, flow cytometry, western blotting, and cell invasion assay. The results demonstrated that hyperforin significantly promotes extrinsic and intrinsic apoptotic pathways, and inhibits cell viability and NF-κB activation. In addition, results also indicated that blockage of NF-κB activation reduces the levels of anti-apoptotic proteins and cell invasion in CL1-5-F4 cells. These results suggested hyperforin induces apoptosis and inhibits NF-κB-modulated anti-apoptotic and invasive potential in NSCLC. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Reduced risk of apoptosis: mechanisms of stress responses.

PubMed

Milisav, Irina; Poljšak, Borut; Ribarič, Samo

2017-02-01

Apoptosis signaling pathways are integrated into a wider network of interconnected apoptotic and anti-apoptotic pathways that regulate a broad range of cell responses from cell death to growth, development and stress responses. An important trigger for anti- or pro-apoptotic cell responses are different forms of stress including hypoxia, energy deprivation, DNA damage or inflammation. Stress duration and intensity determine whether the cell's response will be improved cell survival, due to stress adaptation, or cell death by apoptosis, necrosis or autophagy. Although the interplay between enhanced stress tolerance and modulation of apoptosis triggering is not yet fully understood, there is a substantial body of experimental evidence demonstrating that apoptosis and anti-apoptosis signaling pathways can be manipulated to trigger or delay apoptosis in vitro or in vivo. Anti-apoptotic strategies cover a broad range of approaches. These interventions include mediators that prevent apoptosis (trophic factors and cytokines), apoptosis inhibition (caspase inhibition, stimulation of anti-apoptotic or inhibition of pro-apoptotic proteins and elimination of apoptotic stimulus), adaptive stress responses (induction of maintenance and repair, caspase inactivation) and cell-cell interactions (blocking engulfment and modified micro environment). There is a consensus that preclinical efficacy and safety evaluations of anti-apoptotic strategies should be performed with protocols that simulate as closely as possible the effects of aging, gender, risk factors, comorbidities and co-medications.

Transforming growth factor-β released by apoptotic white blood cells during red blood cell storage promotes transfusion-induced alloimmunomodulation.

PubMed

Vallion, Romain; Bonnefoy, Francis; Daoui, Anna; Vieille, Loredane; Tiberghien, Pierre; Saas, Philippe; Perruche, Sylvain

2015-07-01

Red blood cell (RBC) alloimmunization is a major immunologic risk of transfusion. However, RBC storage facilitates white blood cell (WBC) apoptosis and apoptotic cells have immunomodulatory properties. We investigated the behavior of WBCs, and apoptosis in particular, in RBC units during storage and then studied the impact of WBC apoptosis on the modulation of posttransfusion alloimmunization in RBC products stored short term. We used a mouse model of alloimmunization to transfused HEL-ovalbumin-Duffy (HOD) surface antigen expressed specifically on RBCs. The presence of circulating anti-HOD immunoglobulin G detected by flow cytometry confirmed immunization to HOD+ RBCs. WBC apoptosis and factors released by apoptotic WBCs during storage were determined and in particular the role of transforming growth factor (TGF)-β was assessed on RBC alloimmunization. In blood stored 72 hours, 30% of WBCs were apoptotic, and transfusion of short-term-stored blood resulted in lesser immunization than did fresh blood or stored leukoreduced (LR) RBCs. WBCs undergoing apoptosis released during short-term storage factors modulating RBC alloimmunization. Indeed apoptotic cell-released factors modulate alloimmunization whereas exogenous apoptotic cells directly transfused with LR RBCs did not. While microparticles released during RBC storage had no immunomodulatory role, TGF-β found in the supernatant of stored blood demonstrated the capacity to favor Treg polarization of naïve CD4+CD25- T cells in vitro and limited RBC alloimmunization in vivo. Indeed, addition of recombinant TGF-β to stored LR RBC transfusion strongly limited posttransfusion RBC alloimmunization. Our findings show that short-term storage of non-LR blood facilitates WBC apoptosis therefore releasing TGF-β that modulates posttransfusion RBC alloimmunization. © 2015 AABB.

Photodynamic injury of isolated crayfish neuron and surrounding glial cells: the role of p53

NASA Astrophysics Data System (ADS)

Sharifulina, S. A.; Uzdensky, A. B.

2015-03-01

The pro-apoptotic transcription factor p53 is involved in cell responses to injurious impacts. Using its inhibitor pifithrin- α and activators tenovin-1, RITA and WR-1065, we studied its potential participation in inactivation and death of isolated crayfish mechanoreceptor neuron and satellite glial cells induced by photodynamic treatment, a strong inducer of oxidative stress. In dark, p53 activation by tenovin-1 or WR-1065 shortened activity of isolated neurons. Tenovin-1 and WR-1065 induced apoptosis of glial cells, whereas pifithrin-α was anti-apoptotic. Therefore, p53 mediated glial apoptosis and suppression of neuronal activity after axotomy. Tenovin-1 but not other p53 modulators induced necrosis of axotomized neurons and surrounding glia, possibly, through p53-independent pathway. Under photodynamic treatment, p53 activators tenovin-1 and RITA enhanced glial apoptosis indicating the pro-apoptotic activity of p53. Photoinduced necrosis of neurons and glia was suppressed by tenovin-1 and, paradoxically, by pifithrin-α. Modulation of photoinduced changes in the neuronal activity and necrosis of neurons and glia was possibly p53-independent. The different effects of p53 modulators on neuronal and glial responses to axotomy and photodynamic impact were apparently associated with different signaling pathways in neurons and glial cells.

Targeting autophagy to modulate cell survival: a comparative analysis in cancer, normal and embryonic cells.

PubMed

Divac Rankov, Aleksandra; Ljujić, Mila; Petrić, Marija; Radojković, Dragica; Pešić, Milica; Dinić, Jelena

2017-11-01

Autophagy is linked to multiple cancer-related signaling pathways, and represents a defense mechanism for cancer cells under therapeutic stress. The crosstalk between apoptosis and autophagy is essential for both tumorigenesis and embryonic development. We studied the influence of autophagy on cell survival in pro-apoptotic conditions induced by anticancer drugs in three model systems: human cancer cells (NCI-H460, COR-L23 and U87), human normal cells (HaCaT and MRC-5) and zebrafish embryos (Danio rerio). Autophagy induction with AZD2014 and tamoxifen antagonized the pro-apoptotic effect of chemotherapeutics doxorubicin and cisplatin in cell lines, while autophagy inhibition by wortmannin and chloroquine synergized the action of both anticancer agents. This effect was further verified by assessing cleaved caspase-3 and PARP-1 levels. Autophagy inhibitors significantly increased both apoptotic markers when applied in combination with doxorubicin while autophagy inducers had the opposite effect. In a similar manner, autophagy induction in zebrafish embryos prevented cisplatin-induced apoptosis in the tail region while autophagy inhibition increased cell death in the tail and retina of cisplatin-treated animals. Autophagy modulation with direct inhibitors of the PI3kinase/Akt/mTOR pathway (AZD2014 and wortmannin) triggered the cellular response to anticancer drugs more effectively in NCI-H460 and zebrafish embryonic models compared to HaCaT suggesting that these modulators are selective towards rapidly proliferating cells. Therefore, evaluating the autophagic properties of chemotherapeutics could help determine more accurately the fate of different cell types under treatment. Our study underlines the importance of testing autophagic activity of potential anticancer agents in a comparative approach to develop more rational anticancer therapeutic strategies.

Ellagic acid protects endothelial cells from oxidized low-density lipoprotein-induced apoptosis by modulating the PI3K/Akt/eNOS pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ou, Hsiu-Chung; Lee, Wen-Jane; Tunghai University, Taichung, Taiwan

Endothelial apoptosis is a driving force in atherosclerosis development. Oxidized low-density lipoprotein (oxLDL) promotes inflammatory and thrombotic processes and is highly atherogenic, as it stimulates macrophage cholesterol accumulation and foam cell formation. Previous studies have shown that the phosphatidylinositol 3-kinase/Akt/endothelial nitric oxide synthase/nitric oxide (PI3K/Akt/eNOS/NO) pathway is involved in oxLDL-induced endothelial apoptosis. Ellagic acid, a natural polyphenol found in berries and nuts, has in recent years been the subject of intense research within the fields of cancer and inflammation. However, its protective effects against oxLDL-induced injury in vascular endothelial cells have not been clarified. In the present study, we investigatedmore » the anti-apoptotic effect of ellagic acid in human umbilical vein endothelial cells (HUVECs) exposed to oxLDL and explored the possible mechanisms. Our results showed that pretreatment with ellagic acid (5-20 {mu}M) significantly attenuated oxLDL-induced cytotoxicity, apoptotic features, and generation of reactive oxygen species (ROS). In addition, the anti-apoptotic effect of ellagic acid was partially inhibited by a PI3K inhibitor (wortmannin) and a specific eNOS inhibitor (cavtratin) but not by an ERK inhibitor (PD98059). In exploring the underlying mechanisms of ellagic acid action, we found that oxLDL decreased Akt and eNOS phosphorylation, which in turn activated NF-{kappa}B and downstream pro-apoptotic signaling events including calcium accumulation, destabilization of mitochondrial permeability, and disruption of the balance between pro- and anti-apoptotic Bcl-2 proteins. Those alterations induced by oxLDL, however, were attenuated by pretreatment with ellagic acid. The inhibition of oxLDL-induced endothelial apoptosis by ellagic acid is due at least in part to its anti-oxidant activity and its ability to modulate the PI3K/Akt/eNOS signaling pathway.« less

Taurine protects HK-2 cells from oxidized LDL-induced cytotoxicity via the ROS-mediated mitochondrial and p53-related apoptotic pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, Chun-Yu; Shen, Chao-Yu; Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan

Oxidized LDL (oxLDL) induces a pro-oxidative environment and promotes apoptosis, causing the progression of renal diseases in humans. Taurine is a semi-essential amino acid in mammals and has been shown to be a potent endogenous antioxidant. The kidney plays a pivotal role in maintaining the balance of taurine. However, the mechanisms underlying the protective effects of taurine against oxLDL-induced injury in renal epithelial cells have not been clarified. In the present study, we investigated the anti-apoptotic effects of taurine on human proximal tubular epithelial (HK-2) cells exposed to oxLDL and explored the related mechanisms. We observed that oxLDL increased themore » contents of ROS and of malondialdehyde (MDA), which is a lipid peroxidation by-product that acts as an indicator of the cellular oxidation status. In addition, oxLDL induced cell death and apoptosis in HK-2 cells. Pretreatment with taurine at 100 μM significantly attenuated the oxLDL-induced cytotoxicity. We determined that oxLDL triggered the phosphorylation of ERK and, in turn, the activation of p53 and other apoptosis-related events, including calcium accumulation, destabilization of the mitochondrial permeability and disruption of the balance between pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins. The malfunctions induced by oxLDL were effectively blocked by taurine. Thus, our results suggested that taurine exhibits potential therapeutic activity by preventing oxLDL-induced nephrotoxicity. The inhibition of oxLDL-induced epithelial apoptosis by taurine was at least partially due to its anti-oxidant activity and its ability to modulate the ERK and p53 apoptotic pathways. - Highlights: • Oxidized LDL induced cytotoxicity and apoptosis in HK-2 cells. • Pretreatment with taurine attenuated oxLDL-induced nephrotoxicity. • Taurine protected against renal damages through inhibition of ROS generation. • Taurine prevented apoptosis through modulation of the p53 phosphorylation.« less

Small GTPase CDC-42 promotes apoptotic cell corpse clearance in response to PAT-2 and CED-1 in C. elegans

PubMed Central

Neukomm, L J; Zeng, S; Frei, A P; Huegli, P A; Hengartner, M O

2014-01-01

The rapid clearance of dying cells is important for the well-being of multicellular organisms. In C. elegans, cell corpse removal is mainly mediated by three parallel engulfment signaling cascades. These pathways include two small GTPases, MIG-2/RhoG and CED-10/Rac1. Here we present the identification and characterization of CDC-42 as a third GTPase involved in the regulation of cell corpse clearance. Genetic analyses performed by both loss of cdc-42 function and cdc-42 overexpression place cdc-42 in parallel to the ced-2/5/12 signaling module, in parallel to or upstream of the ced-10 module, and downstream of the ced-1/6/7 module. CDC-42 accumulates in engulfing cells at membranes surrounding apoptotic corpses. The formation of such halos depends on the integrins PAT-2/PAT-3, UNC-112 and the GEF protein UIG-1, but not on the canonical ced-1/6/7 or ced-2/5/12 signaling modules. Together, our results suggest that the small GTPase CDC-42 regulates apoptotic cell engulfment possibly upstream of the canonical Rac GTPase CED-10, by polarizing the engulfing cell toward the apoptotic corpse in response to integrin signaling and ced-1/6/7 signaling in C. elegans. PMID:24632947

Small GTPase CDC-42 promotes apoptotic cell corpse clearance in response to PAT-2 and CED-1 in C. elegans.

PubMed

Neukomm, L J; Zeng, S; Frei, A P; Huegli, P A; Hengartner, M O

2014-06-01

The rapid clearance of dying cells is important for the well-being of multicellular organisms. In C. elegans, cell corpse removal is mainly mediated by three parallel engulfment signaling cascades. These pathways include two small GTPases, MIG-2/RhoG and CED-10/Rac1. Here we present the identification and characterization of CDC-42 as a third GTPase involved in the regulation of cell corpse clearance. Genetic analyses performed by both loss of cdc-42 function and cdc-42 overexpression place cdc-42 in parallel to the ced-2/5/12 signaling module, in parallel to or upstream of the ced-10 module, and downstream of the ced-1/6/7 module. CDC-42 accumulates in engulfing cells at membranes surrounding apoptotic corpses. The formation of such halos depends on the integrins PAT-2/PAT-3, UNC-112 and the GEF protein UIG-1, but not on the canonical ced-1/6/7 or ced-2/5/12 signaling modules. Together, our results suggest that the small GTPase CDC-42 regulates apoptotic cell engulfment possibly upstream of the canonical Rac GTPase CED-10, by polarizing the engulfing cell toward the apoptotic corpse in response to integrin signaling and ced-1/6/7 signaling in C. elegans.

Harnessing Apoptotic Cell Clearance to Treat Autoimmune Arthritis

PubMed Central

Saas, Philippe; Bonnefoy, Francis; Toussirot, Eric; Perruche, Sylvain

2017-01-01

Early-stage apoptotic cells possess immunomodulatory properties. Proper apoptotic cell clearance during homeostasis has been shown to limit subsequent immune responses. Based on these observations, early-stage apoptotic cell infusion has been used to prevent unwanted inflammatory responses in different experimental models of autoimmune diseases or transplantation. Moreover, this approach has been shown to be feasible without any toxicity in patients undergoing allogeneic hematopoietic cell transplantation to prevent graft-versus-host disease. However, whether early-stage apoptotic cell infusion can be used to treat ongoing inflammatory disorders has not been reported extensively. Recently, we have provided evidence that early-stage apoptotic cell infusion is able to control, at least transiently, ongoing collagen-induced arthritis. This beneficial therapeutic effect is associated with the modulation of antigen-presenting cell functions mainly of macrophages and plasmacytoid dendritic cells, as well as the induction of collagen-specific regulatory CD4+ T cells (Treg). Furthermore, the efficacy of this approach is not altered by the association with two standard treatments of rheumatoid arthritis (RA), methotrexate and tumor necrosis factor (TNF) inhibition. Here, in the light of these observations and recent data of the literature, we discuss the mechanisms of early-stage apoptotic cell infusion and how this therapeutic approach can be transposed to patients with RA. PMID:29062314

Harnessing Apoptotic Cell Clearance to Treat Autoimmune Arthritis.

PubMed

Saas, Philippe; Bonnefoy, Francis; Toussirot, Eric; Perruche, Sylvain

2017-01-01

Early-stage apoptotic cells possess immunomodulatory properties. Proper apoptotic cell clearance during homeostasis has been shown to limit subsequent immune responses. Based on these observations, early-stage apoptotic cell infusion has been used to prevent unwanted inflammatory responses in different experimental models of autoimmune diseases or transplantation. Moreover, this approach has been shown to be feasible without any toxicity in patients undergoing allogeneic hematopoietic cell transplantation to prevent graft- versus -host disease. However, whether early-stage apoptotic cell infusion can be used to treat ongoing inflammatory disorders has not been reported extensively. Recently, we have provided evidence that early-stage apoptotic cell infusion is able to control, at least transiently, ongoing collagen-induced arthritis. This beneficial therapeutic effect is associated with the modulation of antigen-presenting cell functions mainly of macrophages and plasmacytoid dendritic cells, as well as the induction of collagen-specific regulatory CD4 + T cells (Treg). Furthermore, the efficacy of this approach is not altered by the association with two standard treatments of rheumatoid arthritis (RA), methotrexate and tumor necrosis factor (TNF) inhibition. Here, in the light of these observations and recent data of the literature, we discuss the mechanisms of early-stage apoptotic cell infusion and how this therapeutic approach can be transposed to patients with RA.

Apoptotic effects of bovine apo-lactoferrin on HeLa tumor cells.

PubMed

Luzi, Carla; Brisdelli, Fabrizia; Iorio, Roberto; Bozzi, Argante; Carnicelli, Veronica; Di Giulio, Antonio; Lizzi, Anna Rita

2017-01-01

Lactoferrin (Lf), a cationic iron-binding glycoprotein of 80 kDa present in body secretions, is known as a compound with marked antimicrobial activity. In the present study, the apoptotic effect of iron-free bovine lactoferrin (apo-bLf) on human epithelial cancer (HeLa) cells was examined in association with reactive oxygen species and glutathione (GSH) levels. Apoptotic effect of iron-free bovine lactoferrin inhibited the growth of HeLa cells after 48 hours of treatment while the diferric-bLf was ineffective in the concentration range tested (from 1 to 12.5 μM). Western blot analysis showed that key apoptotic regulators including Bax, Bcl-2, Sirt1, Mcl-1, and PARP-1 were modulated by 1.25 μM of apo-bLf. In the same cell line, apo-bLf induced apoptosis together with poly (ADP-ribose) polymerase cleavage, caspase activation, and a significant drop of NAD + . In addition, apo-bLf-treated HeLa cells showed a marked increase of reactive oxygen species level and a significant GSH depletion. On the whole, apo-bLf triggered apoptosis of HeLa cells upon oxygen radicals burst and GSH decrease. Copyright © 2017 John Wiley & Sons, Ltd.

Musa paradisiaca inflorescence induces human colon cancer cell death by modulating cascades of transcriptional events.

PubMed

K B, Arun; Madhavan, Aravind; T R, Reshmitha; Thomas, Sithara; Nisha, P

2018-01-24

Colorectal cancer (CRC) is one of the leading causes of cancer death, and diet plays an important role in the etiology of CRC. Traditional medical practitioners in many South Asian countries use plantain inflorescence to treat various gastro-intestinal ailments. The aim of the present study was to investigate the anticancer effects of extracts of inflorescence of Musa paradisiaca against HT29 human colon cancer cells and elucidate the mechanism of these effects by studying the modulation of cascades of transcriptional events. In vitro assays depicted that methanol extract of Musa paradisiaca inflorescence (PIMET) was cytotoxic to HT29 cells. PIMET induced DNA damage and arrested the cell cycle at the G2/M phase. Expression studies showed that PIMET pretreatment upregulates pro-apoptotic Bcl2 and downregulates anti-apoptotic Bax proteins. Different assays showed that the deregulation of pro/antiapoptotic proteins reduces the mitochondrial membrane potential and ATP production; moreover, it enhances cytochrome c release, which triggers the apoptotic pathway, and further cleaves caspase 3 and PARP proteins, resulting in apoptosis. Changes in the protein expression profile of HT29 cells after PIMET treatment were analyzed using mass-spectrometry-based proteomics. PIMET treatment significantly altered the expression of HT29 protein; interestingly, X-linked inhibitor of apoptosis protein was also downregulated. Alteration in the expression of this protein has significant effects, leading to HT29 cell death.

Human and Viral Golgi Anti-apoptotic Proteins (GAAPs) Oligomerize via Different Mechanisms and Monomeric GAAP Inhibits Apoptosis and Modulates Calcium*

PubMed Central

Saraiva, Nuno; Prole, David L.; Carrara, Guia; de Motes, Carlos Maluquer; Johnson, Benjamin F.; Byrne, Bernadette; Taylor, Colin W.; Smith, Geoffrey L.

2013-01-01

Golgi anti-apoptotic proteins (GAAPs) are hydrophobic proteins resident in membranes of the Golgi complex. They protect cells from a range of apoptotic stimuli, reduce the Ca2+ content of intracellular stores, and regulate Ca2+ fluxes. GAAP was discovered in camelpox virus, but it is highly conserved throughout evolution and encoded by all eukaryote genomes examined. GAAPs are part of the transmembrane Bax inhibitor-containing motif (TMBIM) family that also includes other anti-apoptotic and Ca2+-modulating membrane proteins. Most TMBIM members show multiple bands when analyzed by SDS-PAGE, suggesting that they may be oligomeric. However, the molecular mechanisms of oligomerization, the native state of GAAPs in living cells and the functional significance of oligomerization have not been addressed. TMBIM members are thought to have evolved from an ancestral GAAP. Two different GAAPs, human (h) and viral (v)GAAP were therefore selected as models to examine oligomerization of TMBIM family members. We show that both hGAAP and vGAAP in their native states form oligomers and that oligomerization is pH-dependent. Surprisingly, hGAAP and vGAAP do not share the same oligomerization mechanism. Oligomerization of hGAAP is independent of cysteines, but oligomerization of vGAAP depends on cysteines 9 and 60. A mutant vGAAP that is unable to oligomerize revealed that monomeric vGAAP retains both its anti-apoptotic function and its effect on intracellular Ca2+ stores. In conclusion, GAAP can oligomerize in a pH-regulated manner, and monomeric GAAP is functional. PMID:23508950

Apoptotic cell-induced AhR activity is required for immunological tolerance and suppression of systemic lupus erythematosus in mice and humans.

PubMed

Shinde, Rahul; Hezaveh, Kebria; Halaby, Marie Jo; Kloetgen, Andreas; Chakravarthy, Ankur; da Silva Medina, Tiago; Deol, Reema; Manion, Kieran P; Baglaenko, Yuriy; Eldh, Maria; Lamorte, Sara; Wallace, Drew; Chodisetti, Sathi Babu; Ravishankar, Buvana; Liu, Haiyun; Chaudhary, Kapil; Munn, David H; Tsirigos, Aristotelis; Madaio, Michael; Gabrielsson, Susanne; Touma, Zahi; Wither, Joan; De Carvalho, Daniel D; McGaha, Tracy L

2018-06-01

The transcription factor AhR modulates immunity at multiple levels. Here we report that phagocytes exposed to apoptotic cells exhibited rapid activation of AhR, which drove production of the cytokine IL-10. Activation of AhR was dependent on interactions between apoptotic-cell DNA and the pattern-recognition receptor TLR9 that was required for the prevention of immune responses to DNA and histones in vivo. Moreover, disease progression in mouse systemic lupus erythematosus (SLE) correlated with strength of the AhR signal, and the disease course could be altered by modulation of AhR activity. Deletion of AhR in the myeloid lineage caused systemic autoimmunity in mice, and an enhanced AhR transcriptional signature correlated with disease in patients with SLE. Thus, AhR activity induced by apoptotic cell phagocytes maintains peripheral tolerance.

CD147 regulates extrinsic apoptosis in spermatocytes by modulating NFκB signaling pathways

PubMed Central

Wang, Chaoqun; Fok, Kin Lam; Cai, Zhiming; Chen, Hao; Chan, Hsiao Chang

2017-01-01

CD147 null mutant male mice are infertile with arrested spermatogenesis and increased apoptotic germ cells. Our previous studies have shown that CD147 prevents apoptosis in mouse spermatocytes but not spermatogonia. However, the underlying mechanism remains elusive. In the present study, we aim to determine the CD147-regulated apoptotic pathway in mouse spermatocytes. Our results showed that immunodepletion of CD147 triggered apoptosis through extrinsic apoptotic pathway in mouse testis and spermatocyte cell line (GC-2 cells), accompanied by activation of non-canonical NFκB signaling and suppression of canonical NFκB signaling. Furthermore, CD147 was found to interact with TRAF2, a factor known to regulate NFκB and extrinsic apoptotic signaling, and interfering CD147 led to the decrease of TRAF2. Consistently, depletion of CD147 by CRISPR/Cas9 technique in GC-2 cells down-regulated TRAF2 and resulted in cell death with suppressed canonical NFκB and activated non-canonical NFκB signaling. On the contrary, interfering of CD147 had no effect on NFκB signaling pathways as well as TRAF2 protein level in mouse spermatogonia cell line (GC-1 cells). Taken together, these results suggested that CD147 plays a key role in reducing extrinsic apoptosis in spermatocytes, but not spermatogonia, through modulating NFκB signaling pathway. PMID:27902973

CD147 regulates extrinsic apoptosis in spermatocytes by modulating NFκB signaling pathways.

PubMed

Wang, Chaoqun; Fok, Kin Lam; Cai, Zhiming; Chen, Hao; Chan, Hsiao Chang

2017-01-10

CD147 null mutant male mice are infertile with arrested spermatogenesis and increased apoptotic germ cells. Our previous studies have shown that CD147 prevents apoptosis in mouse spermatocytes but not spermatogonia. However, the underlying mechanism remains elusive. In the present study, we aim to determine the CD147-regulated apoptotic pathway in mouse spermatocytes. Our results showed that immunodepletion of CD147 triggered apoptosis through extrinsic apoptotic pathway in mouse testis and spermatocyte cell line (GC-2 cells), accompanied by activation of non-canonical NFκB signaling and suppression of canonical NFκB signaling. Furthermore, CD147 was found to interact with TRAF2, a factor known to regulate NFκB and extrinsic apoptotic signaling, and interfering CD147 led to the decrease of TRAF2. Consistently, depletion of CD147 by CRISPR/Cas9 technique in GC-2 cells down-regulated TRAF2 and resulted in cell death with suppressed canonical NFκB and activated non-canonical NFκB signaling. On the contrary, interfering of CD147 had no effect on NFκB signaling pathways as well as TRAF2 protein level in mouse spermatogonia cell line (GC-1 cells). Taken together, these results suggested that CD147 plays a key role in reducing extrinsic apoptosis in spermatocytes, but not spermatogonia, through modulating NFκB signaling pathway.

Remodeling of adhesion and modulation of mechanical tensile forces during apoptosis in Drosophila epithelium.

PubMed

Teng, Xiang; Qin, Lei; Le Borgne, Roland; Toyama, Yusuke

2017-01-01

Apoptosis is a mechanism of eliminating damaged or unnecessary cells during development and tissue homeostasis. During apoptosis within a tissue, the adhesions between dying and neighboring non-dying cells need to be remodeled so that the apoptotic cell is expelled. In parallel, contraction of actomyosin cables formed in apoptotic and neighboring cells drives cell extrusion. To date, the coordination between the dynamics of cell adhesion and the progressive changes in tissue tension around an apoptotic cell is not fully understood. Live imaging of histoblast expansion, which is a coordinated tissue replacement process during Drosophila metamorphosis, shows remodeling of adherens junctions (AJs) between apoptotic and non-dying cells, with a reduction in the levels of AJ components, including E-cadherin. Concurrently, surrounding tissue tension is transiently released. Contraction of a supra-cellular actomyosin cable, which forms in neighboring cells, brings neighboring cells together and further reshapes tissue tension toward the completion of extrusion. We propose a model in which modulation of tissue tension represents a mechanism of apoptotic cell extrusion. © 2017. Published by The Company of Biologists Ltd.

Chromium (VI)-induced oxidative stress, apoptotic cell death and modulation of p53 tumor suppressor gene.

PubMed

Bagchi, D; Bagchi, M; Stohs, S J

2001-06-01

Chromium (VI) is a widely used industrial chemical, extensively used in paints, metal finishes, steel including stainless steel manufacturing, alloy cast irons, chrome, and wood treatment. On the contrary, chromium (III) salts such as chromium polynicotinate, chromium chloride and chromium picolinate, are used as micronutrients and nutritional supplements, and have been demonstrated to exhibit a significant number of health benefits in rodents and humans. However, the cause for the hexavalent chromium to induce cytotoxicity is not entirely understood. A series of in vitro and in vivo studies have demonstrated that chromium (VI) induces an oxidative stress through enhanced production of reactive oxygen species (ROS) leading to genomic DNA damage and oxidative deterioration of lipids and proteins. A cascade of cellular events occur following chromium (VI)-induced oxidative stress including enhanced production of superoxide anion and hydroxyl radicals, increased lipid peroxidation and genomic DNA fragmentation, modulation of intracellular oxidized states, activation of protein kinase C, apoptotic cell death and altered gene expression. In this paper, we have demonstrated concentration- and time-dependent effects of sodium dichromate (chromium (VI) or Cr (VI)) on enhanced production of superoxide anion and hydroxyl radicals, changes in intracellular oxidized states as determined by laser scanning confocal microscopy, DNA fragmentation and apoptotic cell death (by flow cytometry) in human peripheral blood mononuclear cells. These results were compared with the concentration-dependent effects of chromium (VI) on chronic myelogenous leukemic K562 cells and J774A.1 murine macrophage cells. Chromium (VI)-induced enhanced production of ROS, as well as oxidative tissue and DNA damage were observed in these cells. More pronounced effect was observed on chronic myelogenous leukemic K562 cells and J774A.1 murine macrophage cells. Furthermore, we have assessed the effect of a single oral LD50 dose of chromium (VI) on female C57BL/6Ntac and p53-deficient C57BL/6TSG p53 mice on enhanced production of superoxide anion, lipid peroxidation and DNA fragmentation in the hepatic and brain tissues. Chromium (VI)-induced more pronounced oxidative damage in p53 deficient mice. This in vivo study highlighted that apoptotic regulatory protein p53 may play a major role in chromium (VI)-induced oxidative stress and toxicity. Taken together, oxidative stress and oxidative tissue damage, and a cascade of cellular events including modulation of apoptotic regulatory gene p53 are involved in chromium (VI)-induced toxicity and carcinogenesis.

N-3 poly-unsaturated fatty acids shift estrogen signaling to inhibit human breast cancer cell growth.

PubMed

Cao, Wenqing; Ma, ZhiFan; Rasenick, Mark M; Yeh, ShuYan; Yu, JiangZhou

2012-01-01

Although evidence has shown the regulating effect of n-3 poly-unsaturated fatty acid (n-3 PUFA) on cell signaling transduction, it remains unknown whether n-3 PUFA treatment modulates estrogen signaling. The current study showed that docosahexaenoic acid (DHA, C22:6), eicosapentaenoic acid (EPA, C20:5) shifted the pro-survival and proliferative effect of estrogen to a pro-apoptotic effect in human breast cancer (BCa) MCF-7 and T47D cells. 17 β-estradiol (E2) enhanced the inhibitory effect of n-3 PUFAs on BCa cell growth. The IC50 of DHA or EPA in MCF-7 cells decreased when combined with E2 (10 nM) treatment (from 173 µM for DHA only to 113 µM for DHA+E2, and from 187 µm for EPA only to 130 µm for EPA+E2). E2 also augmented apoptosis in n-3 PUFA-treated BCa cells. In contrast, in cells treated with stearic acid (SA, C18:0) as well as cells not treated with fatty acid, E2 promoted breast cancer cell growth. Classical (nuclear) estrogen receptors may not be involved in the pro-apoptotic effects of E2 on the n-3 PUFA-treated BCa cells because ERα agonist failed to elicit, and ERα knockdown failed to block E2 pro-apoptotic effects. Subsequent studies reveal that G protein coupled estrogen receptor 1 (GPER1) may mediate the pro-apoptotic effect of estrogen. N-3 PUFA treatment initiated the pro-apoptotic signaling of estrogen by increasing GPER1-cAMP-PKA signaling response, and blunting EGFR, Erk 1/2, and AKT activity. These findings may not only provide the evidence to link n-3 PUFAs biologic effects and the pro-apoptotic signaling of estrogen in breast cancer cells, but also shed new insight into the potential application of n-3 PUFAs in BCa treatment.

Modulation of caspases and their non-apoptotic functions by Legionella pneumophila.

PubMed

Amer, Amal O

2010-02-01

Legionella pneumophila has become a model system to decipher the non-apoptotic functions of caspases and their role in immunity. In permissive cells, the L. pneumophila-containing vacuole evades endosomal traffic and is remodelled by the endoplasmic reticulum. Evasion of the endosomes is mediated by the Dot/Icm type IV secretion system. Upon L. pneumophila infection of genetically restrictive cells such as wild-type (WT) C57Bl/6J murine macrophages, flagellin is sensed by the NOD-like receptor Nlrc4 leading to caspase-1 activation by the inflammasome complex. Then, caspase-7 is activated downstream of the Nlrc4 inflammasome, promoting non-apoptotic functions such as L. pneumophila-containing phagosome maturation and bacterial degradation. Interestingly, caspase-3 is activated in permissive cells during early stages of infection. However, caspase-3 activation does not lead to apoptosis until late stages of infection because it is associated with potent Dot/Icm-mediated anti-apoptotic stimuli that render the infected cells resistant to external apoptotic inducers. Therefore, the role of caspase-1 and non-apoptotic functions of executioner caspases are temporally and spatially modulated during infection by L. pneumophila, which determine permissiveness to intracellular bacterial proliferation. This review will examine the novel activation pathways of caspases by L. pneumophila and discuss their role in genetic restriction and permissiveness to infection.

Hsp70 suppresses apoptosis of BRL cells by regulating the expression of Bcl-2, cytochrome C, and caspase 8/3.

PubMed

Kong, Fanzhi; Wang, Hui; Guo, Jingru; Peng, Mengling; Ji, Hong; Yang, Huanmin; Liu, Binrun; Wang, Jianfa; Zhang, Xu; Li, Shize

2016-05-01

During cold stress, liver cells undergo apoptotic injury as a result of oxidative stress. Heat shock 70 kDa protein (Hsp70) is a protein involved in modulating a variety of physiological processes, including stress responses, proliferation, and apoptosis. In addition, Hsp70 regulates apoptotic signaling pathways in different manners, promoting or suppressing apoptosis. In this study, we investigated the effects of Hsp70 overexpression on hydrogen peroxide (H2O2)-induced apoptosis of Buffalo rat liver (BRL) cells and the underlying mechanisms of these effects. Our results show that in comparison with the control group, Hsp70 overexpression displayed increased protein levels of Bcl-2, and decreased cytochrome c (Cyt c), cleaved caspase 3, and cleaved caspase 8, but no apparent differences were found in levels of Bax. Furthermore, Hsp70 overexpression significantly suppresses the amount of apoptotic cells. Such findings indicate that overexpression of Hsp70 inhibits H2O2-mediated activation of caspase 8 and caspase 3, upregulates the expression of Bcl-2 which is a known anti-apoptotic protein, and decreases the release of Cyt c from the mitochondria into the cytoplasm, collectively decreasing cell apoptosis.

Astaxanthin Inhibits Acetaldehyde-Induced Cytotoxicity in SH-SY5Y Cells by Modulating Akt/CREB and p38MAPK/ERK Signaling Pathways.

PubMed

Yan, Tingting; Zhao, Yan; Zhang, Xia; Lin, Xiaotong

2016-03-10

Excessive alcohol consumption can lead to brain tissue damage and cognitive dysfunction. Acetaldehyde, the most toxic metabolite of ethanol, mediates the brain tissue damage and cognitive dysfunction induced by chronic excessive alcohol consumption. In this study, the effect of astaxanthin, a marine bioactive compound, on acetaldehyde-induced cytotoxicity was investigated in SH-SY5Y cells. It was found that astaxanthin protected cells from apoptosis by ameliorating the effect of acetaldehyde on the expression of Bcl-2 family proteins, preventing the reduction of anti-apoptotic protein Bcl-2 and the increase of pro-apoptotic protein Bak induced by acetaldehyde. Further analyses showed that astaxanthin treatment inhibited acetaldehyde-induced reduction of the levels of activated Akt and cyclic AMP-responsive element binding protein (CREB). Astaxanthin treatment also prevented acetaldehyde-induced increase of the level of activated p38 mitogen-activated protein kinase (MAPK) and decrease of the level of activated extracellular signal-regulated kinases (ERKs). Activation of Akt/CREB pathway promotes cell survival and is involved in the upregulation of Bcl-2 gene. P38MAPK plays a critical role in apoptotic events while ERKs mediates the inhibition of apoptosis. Thus, astaxanthin may inhibit acetaldehyde-induced apoptosis through promoting the activation of Akt/CREB and ERKs and blocking the activation of p38MAPK. In addition, astaxanthin treatment suppressed the oxidative stress induced by acetaldehyde and restored the antioxidative capacity of SH-SY5Y cells. Therefore, astaxanthin may protect cells against acetaldehyde-induced cytotoxicity through maintaining redox balance and modulating apoptotic and survival signals. The results suggest that astaxanthin treatment may be beneficial for preventing neurotoxicity associated with acetaldehyde and excessive alcohol consumption.

Regucalcin is an androgen-target gene in the rat prostate modulating cell-cycle and apoptotic pathways.

PubMed

Vaz, Cátia V; Maia, Cláudio J; Marques, Ricardo; Gomes, Inês M; Correia, Sara; Alves, Marco G; Cavaco, José E; Oliveira, Pedro F; Socorro, Sílvia

2014-09-01

Regucalcin (RGN) is a calcium (Ca(2+) )-binding protein underexpressed in prostate adenocarcinoma comparatively to non-neoplastic prostate or benign prostate hyperplasia cases. Moreover, RGN expression is negatively associated with the cellular differentiation of prostate adenocarcinoma, suggesting that loss of RGN may be associated with tumor onset and progression. However, the RGN actions over the control of prostate cell growth have not been investigated. Androgens are implicated in the promotion of prostate cell proliferation, thus we studied the in vivo effect of androgens on RGN expression in rat prostate. The role of RGN modulating cell proliferation and apoptotic pathways in rat prostate was investigated using transgenic animals (Tg-RGN) overexpressing the protein. In vivo stimulation with 5α-dihydrotestosterone (DHT) down-regulated RGN expression in rat prostate. Cell proliferation index and prostate weight were reduced in Tg-RGN, which was concomitant with altered expression of cell-cycle regulators. Tg-RGN presented diminished expression of the oncogene H-ras and increased expression of cell-cycle inhibitor p21. Levels of anti-apoptotic Bcl-2, as well as the Bcl-2/Bax protein ratio were increased in prostates overexpressing RGN. Both caspase-3 expression and enzyme activity were decreased in the prostates of Tg-RGN. Overexpression of RGN resulted in inhibition of cell proliferation and apoptotic pathways, which demonstrated its role maintaining prostate growth balance. Thus, deregulation of RGN expression may be an important event favoring the development of prostate cancer. Moreover, the DHT effect down-regulating RGN expression in rat prostate highlighted for the importance of this protein in prostatic physiology. © 2014 Wiley Periodicals, Inc.

Chinonin, a novel drug against cardiomyocyte apoptosis induced by hypoxia and reoxygenation.

PubMed

Shen, J G; Quo, X S; Jiang, B; Li, M; Xin, W; Zhao, B L

2000-02-21

The inhibitory effects of Chinonin, a natural antioxidant extracted from a Chinese medicine, on apoptotic and necrotic cell death of cardiomyocytes in hypoxia-reoxygenation process were observed in this study. The possible mechanisms of Chinonin on scavenging reactive oxygen species and regulating apoptotic related genes bcl-2 and p53 were also investigated. Neonatal rat cardiomyocytes were subjected to 24-h hypoxia and 4-h reoxygenation. Cell death was evaluated by DNA electrophoresis on agarose gel, cell death ELISA and annexin-V-FLUOS/propidium iodide (PI) double staining cytometry. Hypoxia caused the increase of apoptotic rates and the release of lactate dehydrogenase (LDH), while reoxygenation not only further increased the apoptotic rates and leakage of LDH, but also induced necrosis of cardiomyocytes. In addition, hypoxia increased the levels of NO(2)(-)/NO(3)(-) and thiobarbituric acid reacted substances (TBARS), while reoxygenation decreased NO(2)(-)/NO(3)(-), but further increased TBARS in the cultured media. Moreover, hypoxia up-regulated the expression levels of bcl-2 and p53 proteins, while reoxygenation down-regulated bcl-2 and further up-regulated p53. Chinonin significantly decreased the rates of apoptotic and necrotic cardiomyocytes, and inhibited the leakage of LDH. It also diminished NO(2)(-)/NO(3)(-) and TBARS, down-regulated the expression level of p53 protein, and up-regulated bcl-2 protein, respectively. The results suggest that Chinonin has preventive effects against apoptotic and necrotic cell death and its protective mechanisms are related to the antioxidant properties of scavenging nitric oxide and oxygen free radicals, and the modulating effects on the expression levels of bcl-2 and p53 proteins.

4β-Hydroxywithanolide E Modulates Alternative Splicing of Apoptotic Genes in Human Hepatocellular Carcinoma Huh-7 Cells.

PubMed

Lee, Chien-Chin; Chang, Wen-Hsin; Chang, Ya-Sian; Liu, Ting-Yuan; Chen, Yu-Chia; Wu, Yang-Chang; Chang, Jan-Gowth

2017-08-04

Alternative splicing is a mechanism for increasing protein diversity from a limited number of genes. Studies have demonstrated that aberrant regulation in the alternative splicing of apoptotic gene transcripts may contribute to the development of cancer. In this study, we isolated 4β-Hydroxywithanolide E (4bHWE) from the traditional herb Physalis peruviana and investigated its biological effect in cancer cells. The results demonstrated that 4bHWE modulates the alternative splicing of various apoptotic genes, including HIPK3, SMAC/DIABLO, and SURVIVIN. We also discovered that the levels of SRSF1 phospho-isoform were decreased and the levels of H3K36me3 were increased in 4bHWE treatment. Knockdown experiments revealed that the splicing site selection of SMAC/DIABLO could be mediated by changes in the level of H3K36me3 in 4bHWE-treated cells. Furthermore, we extended our study to apoptosis-associated molecules, and detected increased levels of poly ADP-ribose polymerase cleavage and the active form of CASPASE-3 in 4bHWE-induced apoptosis. In vivo experiments indicated that the treatment of tumor-bearing mice with 4bHWE resulted in a marked decrease in tumor size. This study is the first to demonstrate that 4bHWE affects alternative splicing by modulating splicing factors and histone modifications, and provides a novel view of the antitumor mechanism of 4bHWE.

The effect of Astragalus polysaccharides on attenuation of diabetic cardiomyopathy through inhibiting the extrinsic and intrinsic apoptotic pathways in high glucose -stimulated H9C2 cells.

PubMed

Sun, Shuqin; Yang, Shuo; Dai, Min; Jia, Xiujuan; Wang, Qiyan; Zhang, Zheng; Mao, Yongjun

2017-06-13

Apoptosis plays a critical role in the progression of diabetic cardiomyopathy (DC). Astragalus polysaccharides (APS), an extract of astragalus membranaceus (AM), is an effective cardioprotectant. Currently, little is known about the detailed mechanisms underlying cardioprotective effects of APS. The aims of this study were to investigate the potential effects and mechanisms of APS on apoptosis employing a model of high glucose induction of apoptosis in H9C2 cells. A model of high glucose induction of H9C2 cell apoptosis was adopted in this research. The cell viabilities were analyzed by MTT assay, and the apoptotic response was quantified by flow cytometry. The expression levels of the apoptosis related proteins were determined by Real-time PCR and western blotting. Incubation of H9C2 cells with various concentrations of glucose (i.e., 5.5, 12.5, 25, 33 and 44 mmol/L) for 24 h revealed that cell viability was reduced by high glucose dose-dependently. Pretreatment of cells with APS could inhibit high glucose-induced H9C2 cell apoptosis by decreasing the expressions of caspases and the release of cytochrome C from mitochondria to cytoplasm. Further experiments also showed that APS could modulate the ratio of Bcl-2 to Bax in mitochondria. APS decreases high glucose-induced H9C2 cell apoptosis by inhibiting the expression of pro-apoptotic proteins of both the extrinsic and intrinsic pathways and modulating the ratio of Bcl-2 to Bax in mitochondria.

Cardiolipin modulates allosterically peroxynitrite detoxification by horse heart cytochrome c

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ascenzi, Paolo, E-mail: ascenzi@uniroma3.it; Ciaccio, Chiara; Interuniversity Consortium for the Research on the Chemistry of Metals in Biological Systems, I-70126 Bari

2011-01-07

Research highlights: {yields} Cardiolipin binding to cytochrome c. {yields} Cardiolipin-dependent peroxynitrite isomerization by cytochrome c. {yields} Cardiolipin-cytochrome c complex plays pro-apoptotic effects. {yields} Cardiolipin-cytochrome c complex plays anti-apoptotic effects. -- Abstract: Upon interaction with bovine heart cardiolipin (CL), horse heart cytochrome c (cytc) changes its tertiary structure disrupting the heme-Fe-Met80 distal bond, reduces drastically the midpoint potential out of the range required for its physiological role, binds CO and NO with high affinity, and displays peroxidase activity. Here, the effect of CL on peroxynitrite isomerization by ferric cytc (cytc-Fe(III)) is reported. In the absence of CL, hexa-coordinated cytc does notmore » catalyze peroxynitrite isomerization. In contrast, CL facilitates cytc-Fe(III)-mediated isomerization of peroxynitrite in a dose-dependent fashion inducing the penta-coordination of the heme-Fe(III)-atom. The value of the second order rate constant for CL-cytc-Fe(III)-mediated isomerization of peroxynitrite (k{sub on}) is (3.2 {+-} 0.4) x 10{sup 5} M{sup -1} s{sup -1}. The apparent dissociation equilibrium constant for CL binding to cytc-Fe(III) is (5.1 {+-} 0.8) x 10{sup -5} M. These results suggest that CL-cytc could play either pro-apoptotic or anti-apoptotic effects facilitating lipid peroxidation and scavenging of reactive nitrogen species, such as peroxynitrite, respectively.« less

Combinatorial effect of curcumin with docetaxel modulates apoptotic and cell survival molecules in prostate cancer

PubMed Central

Banerjee, Saswati; Singh, Santosh K.; Chowdhury, Indrajit; Lillard, James W.; Singh, Rajesh

2017-01-01

Docetaxel is the most commonly used chemotherapeutic agent to target androgen signaling in metastatic prostate cancer (PCa); however, prolonged treatment with docetaxel results in drug-resistant cancer cells. Combination therapies have the potential of increasing the effectiveness of drug treatment as well as decreasing the side effects. Curcumin is a nontoxic organic compound with multifaceted chemopreventive potential. In this study, we evaluated whether curcumin can reinforce the effect of docetaxel on PCa cells. The PCa cell lines DU145 and PC3 were treated with curcumin and docetaxel alone or in combination. After completion of the treatment cell proliferation and the expression of pro-survival and anti-apoptotic markers and the signaling molecules were analyzed. The combined treatment of curcumin and docetaxel inhibited the proliferation and induced apoptosis significantly higher than the curcumin and docetaxel-treated group alone. Interestingly, the combined treatment with curcumin and docetaxel modulates the expression of RTKs, PI3K, phospho-AKT, NF-kappa B, p53, and COX-2. These results suggest that curcumin can be a potential therapeutic contender in enhancing the efficacy of docetaxel in PCa treatment. PMID:28199187

Attacking Cancer’s Achilles Heel: Antagonism of Anti-Apoptotic BCL-2 Family Members

PubMed Central

Opferman, Joseph T.

2015-01-01

Malignant cells routinely violate cellular checkpoints that should initiate cell death in normal cells by triggering pro-apoptotic members of the BCL-2 family of proteins. To escape such death inducing signals, cancer cells often select for up regulation of anti-apoptotic BCL-2 family members including BCL-2, BCL-XL, BFL-1, BCL-W, and MCL-1. These family members prevent death by sequestering pro-apoptotic molecules. To counter this resistance mechanism, small molecule inhibitors of anti-apoptotic BCL-2 family members have been under development. These molecules have shown promise in pre-clinical and clinical testing to overcome apoptotic resistance, prompting cancer cells to undergo apoptosis. Alternatively, other strategies have taken advantage of the normal regulatory machinery controlling anti-apoptotic molecules and have used inhibitors of signaling pathways to down-modulate the expression of anti-apoptotic molecules thus tilting the balance in cancer cells to cell death. This review explores recent developments and strategies aimed at antagonizing anti-apoptotic BCL-2 family member action to promote the induction of cell death in cancer therapy. PMID:26293580

Modulation of ovarian follicle maturation and effects on apoptotic cell death in Holtzman rats exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in utero and lactationally.

PubMed

Heimler, I; Trewin, A L; Chaffin, C L; Rawlins, R G; Hutz, R J

1998-01-01

Recent reports have described the reproduction-modulating and endocrine-disrupting effects following exposure to toxic substances such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Herein, we set out (1) to determine whether TCDD exposure exerts detrimental effects on follicle maturation in the Holtzman rat ovary and (2) to determine whether the effects of TCDD are mediated in part via apoptotic cell death. In certain species, dioxin exposure is correlated with reduced fecundity, reduced ovulatory rate, an increased incidence of endometriosis, and various reproductive cancers. Although some of the effects of TCDD are mediated via the hypothalamic-pituitary axis, direct effects on the ovary have also been observed. In the present study, an oral dose of 1 microgram TCDD/kg maternal body weight was administered on Day 15 of gestation. Female pups were sacrificed on Postnatal Day 21/22, and the ovaries were excised, fixed for histologic analysis, and analyzed in a double-blind paradigm. The analysis included a count and measurement and classification of preantral and antral follicles throughout the entire ovary. The contralateral ovary from each animal was analyzed for DNA fragmentation indicative of apoptotic cell death. The results indicate that TCDD treatment significantly reduced the number of antral follicles in the size classes 50,000 to 74,999 microns2 and > 100,000 microns2. We also observed a reduction in the number of preantral follicles less than 50,000 microns2. No difference was observed in the degree of apoptotic cell death in antral (50,000 to > 100,000 microns2) and preantral follicles (50,000 microns2 to > 75,000 microns2) between TCDD-treated and control-treated tissues. These data support the hypothesis that TCDD results in a diminution in the number of antral and preantral follicles of certain size classes in animals exposed during critical periods of development, but that apoptosis does not appear to be the underlying mechanism in these particular follicles. This does not preclude apoptosis occurring in pools of smaller precursor follicles.

The production of nitric oxide in the coeliac ganglion modulates the effect of cholinergic neurotransmission on the rat ovary during the preovulatory period.

PubMed

Delsouc, María B; Della Vedova, María C; Ramírez, Darío; Delgado, Silvia M; Casais, Marilina

2018-05-01

The aim of the present work was to investigate whether the nitric oxide produced by the nitric oxide/nitric oxide synthase (NO/NOS) system present in the coeliac ganglion modulates the effects of cholinergic innervation on oxidative status, steroidogenesis and apoptotic mechanisms that take place in the rat ovary during the first proestrous. An ex vivo Coeliac Ganglion- Superior Ovarian Nerve- Ovary (CG-SON-O) system was used. Cholinergic stimulation of the CG was achieved by 10 -6  M Acetylcholine (Ach). Furthermore, 400 μM Aminoguanidine (AG) - an inhibitor of inducible-NOS was added in the CG compartment in absence and presence of Ach. It was found that Ach in the CG compartment promotes apoptosis in ovarian tissue, probably due to the oxidative stress generated. AG in the CG compartment decreases the release of NO and progesterone, and increases the release of estradiol from the ovary. The CG co-treatment with Ach and AG counteracts the effects of the ganglionic cholinergic agonist on ovarian oxidative stress, increases hormone production and decreases Fas mRNA expression. These results suggest that NO is an endogenous modulator of cholinergic neurotransmission in CG, with implication in ovarian steroidogenesis and the apoptotic mechanisms that take place in the ovary during the preovulatory period in rats. Copyright © 2018 Elsevier Inc. All rights reserved.

Directing an appropriate immune response: the role of defense collagens and other soluble pattern recognition molecules.

PubMed

Fraser, D A; Tenner, A J

2008-02-01

Defense collagens and other soluble pattern recognition receptors contain the ability to recognize and bind molecular patterns associated with pathogens (PAMPs) or apoptotic cells (ACAMPs) and signal appropriate effector-function responses. PAMP recognition by defense collagens C1q, MBL and ficolins leads to rapid containment of infection via complement activation. However, in the absence of danger, such as during the clearance of apoptotic cells, defense collagens such as C1q, MBL, ficolins, SP-A, SP-D and even adiponectin have all been shown to facilitate enhanced phagocytosis and modulate induction of cytokines towards an anti-inflammatory profile. In this way, cellular debris can be removed without provoking an inflammatory immune response which may be important in the prevention of autoimmunity and/or resolving inflammation. Indeed, deficiencies and/or knock-out mouse studies have highlighted critical roles for soluble pattern recognition receptors in the clearance of apoptotic bodies and protection from autoimmune diseases along with mediating protection from specific infections. Understanding the mechanisms involved in defense collagen and other soluble pattern recognition receptor modulation of the immune response may provide important novel insights into therapeutic targets for infectious and/or autoimmune diseases and additionally may identify avenues for more effective vaccine design.

Improved bioavailability of targeted Curcumin delivery efficiently regressed cardiac hypertrophy by modulating apoptotic load within cardiac microenvironment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ray, Aramita, E-mail: aramitaray@yahoo.co.in; Rana, Santanu, E-mail: rana.santanu@gmail.com; Banerjee, Durba, E-mail: durba.research@gmail.com

Cardiomyocyte apoptosis acts as a prime modulator of cardiac hypertrophy leading to heart failure, a major cause of human mortality worldwide. Recent therapeutic interventions have focussed on translational applications of diverse pharmaceutical regimes among which, Curcumin (from Curcuma longa) is known to have an anti-hypertrophic potential but with limited pharmacological efficacies due to low aqueous solubility and poor bioavailability. In this study, Curcumin encapsulated by carboxymethyl chitosan (CMC) nanoparticle conjugated to a myocyte specific homing peptide was successfully delivered in bioactive form to pathological myocardium for effective regression of cardiac hypertrophy in a rat (Rattus norvegicus) model. Targeted nanotization showedmore » higher cardiac bioavailability of Curcumin at a low dose of 5 mg/kg body weight compared to free Curcumin at 35 mg/kg body weight. Moreover, Curcumin/CMC-peptide treatment during hypertrophy significantly improved cardiac function by downregulating expression of hypertrophy marker genes (ANF, β-MHC), apoptotic mediators (Bax, Cytochrome-c) and activity of apoptotic markers (Caspase 3 and PARP); whereas free Curcumin in much higher dose showed minimal improvement during compromised cardiac function. Targeted Curcumin treatment significantly lowered p53 expression and activation in diseased myocardium via inhibited interaction of p53 with p300-HAT. Thus attenuated acetylation of p53 facilitated p53 ubiquitination and reduced the apoptotic load in hypertrophied cardiomyocytes; thereby limiting cardiomyocytes' need to enter the regeneration cycle during hypertrophy. This study elucidates for the first time an efficient targeted delivery regimen for Curcumin and also attributes towards probable mechanistic insight into its therapeutic potential as a cardio-protective agent for regression of cardiac hypertrophy. - Highlights: • Cardiomyocyte targeted Curcumin/CMC-peptide increases bioavailability of the drug. • Curcumin nanoparticle regresses cardiac hypertrophy by reducing myocyte apoptosis. • Targeted Curcumin shows higher efficacy over free Curcumin to regress hypertrophy. • Curcumin modulates p300-HAT axis to facilitate p53 degradation.« less

Oxidative and apoptotic effects of lambda-cyhalothrin modulated by piperonyl butoxide in the liver of Oreochromis niloticus.

PubMed

Piner, Petek; Uner, Nevin

2012-05-01

The aim of this study was to investigate the toxic effects of pyrethroid pesticide lambda-cyhalothrin in the presence of piperonyl butoxide as a modulator in the liver of juvenile Oreochromis niloticus. LC(50) (96h) value of lambda-cyhalothrin was determined as 2.901μg/L for O. niloticus. The fish were exposed to 0.48μg/L (1/6 of the 96-h LC(50)) lambda-cyhalothrin and 10μg/L piperonyl butoxide for 96-h and 15-d. tGSH, GSH, GSSG, Hsp70 and TBARS contents, GPx, GR, GST and caspase-3 enzymes activities were determined. Lambda-cyhalothrin caused increases in tGSH, GSH, TBARS contents, and GST activity. Piperonyl butoxide treatment with lambda-cyhalothrin caused significant increases in tGSH GSH, Hsp70, TBARS contents, and GPx and GST activities while caspase-3 activity was decreased. The results of the present study revealed that lambda-cyhalothrin caused oxidative stress which upregulated GSH and GSH-related enzymes. Piperonyl butoxide increased the oxidative stress potential and apoptotic effects of lambda-cyhalothrin. Copyright © 2012 Elsevier B.V. All rights reserved.

Silymarin modulates doxorubicin-induced oxidative stress, Bcl-xL and p53 expression while preventing apoptotic and necrotic cell death in the liver

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patel, Nirav; Joseph, Cecil; Corcoran, George B.

2010-06-01

The emergence of silymarin (SMN) as a natural remedy for liver diseases, coupled with its entry into NIH clinical trial, signifies its hepatoprotective potential. SMN is noted for its ability to interfere with apoptotic signaling while acting as an antioxidant. This in vivo study was designed to explore the hepatotoxic potential of Doxorubicin (Dox), the well-known cardiotoxin, and in particular whether pre-exposures to SMN can prevent hepatotoxicity by reducing Dox-induced free radical mediated oxidative stress, by modulating expression of apoptotic signaling proteins like Bcl-xL, and by minimizing liver cell death occurring by apoptosis or necrosis. Groups of male ICR micemore » included Control, Dox alone, SMN alone, and Dox with SMN pre/co-treatment. Control and Dox groups received saline i.p. for 14 days. SMN was administered p.o. for 14 days at 16 mg/kg/day. An approximate LD{sub 50} dose of Dox, 60 mg/kg, was administered i.p. on day 12 to animals receiving saline or SMN. Animals were euthanized 48 h later. Dox alone induced frank liver injury (> 50-fold increase in serum ALT) and oxidative stress (> 20-fold increase in malondialdehyde [MDA]), as well as direct damage to DNA (> 15-fold increase in DNA fragmentation). Coincident genomic damage and oxidative stress influenced genomic stability, reflected in increased PARP activity and p53 expression. Decreases in Bcl-xL protein coupled with enhanced accumulation of cytochrome c in the cytosol accompanied elevated indexes of apoptotic and necrotic cell death. Significantly, SMN exposure reduced Dox hepatotoxicity and associated apoptotic and necrotic cell death. The effects of SMN on Dox were broad, including the ability to modulate changes in both Bcl-xL and p53 expression. In animals treated with SMN, tissue Bcl-xL expression exceeded control values after Dox treatment. Taken together, these results demonstrated that SMN (i) reduced, delayed onset, or prevented toxic effects of Dox which are typically associated with hydroxyl radical production, (ii) performed as an antioxidant limiting oxidative stress, (iii) protected the integrity of the genome, and (iv) antagonized apopotic and necrotic cell death while increasing antiapoptotic Bcl-xL protein levels and minimizing the leakage of proapoptotic cytochrome c from liver mitochondria. These observations demonstrate the protective actions of SMN in liver, and raise the possibility that such protection may extend to other organs during Dox treatment including the heart.« less

Adiponectin modulates inflammatory reactions via calreticulin receptor–dependent clearance of early apoptotic bodies

PubMed Central

Takemura, Yukihiro; Ouchi, Noriyuki; Shibata, Rei; Aprahamian, Tamar; Kirber, Michael T.; Summer, Ross S.; Kihara, Shinji; Walsh, Kenneth

2007-01-01

Obesity and type 2 diabetes are associated with chronic inflammation. Adiponectin is an adipocyte-derived hormone with antidiabetic and antiinflammatory actions. Here, we demonstrate what we believe to be a previously undocumented activity of adiponectin, facilitating the uptake of early apoptotic cells by macrophages, an essential feature of immune system function. Adiponectin-deficient (APN-KO) mice were impaired in their ability to clear apoptotic thymocytes in response to dexamethasone treatment, and these animals displayed a reduced ability to clear early apoptotic cells that were injected into their intraperitoneal cavities. Conversely, adiponectin administration promoted the clearance of apoptotic cells by macrophages in both APN-KO and wild-type mice. Adiponectin overexpression also promoted apoptotic cell clearance and reduced features of autoimmunity in lpr mice whereas adiponectin deficiency in lpr mice led to a further reduction in apoptotic cell clearance, which was accompanied by exacerbated systemic inflammation. Adiponectin was capable of opsonizing apoptotic cells, and phagocytosis of cell corpses was mediated by the binding of adiponectin to calreticulin on the macrophage cell surface. We propose that adiponectin protects the organism from systemic inflammation by promoting the clearance of early apoptotic cells by macrophages through a receptor-dependent pathway involving calreticulin. PMID:17256056

Flavonoids in Ginkgo biloba fallen leaves induce apoptosis through modulation of p53 activation in melanoma cells.

PubMed

Park, Hye-Jung; Kim, Moon-Moo

2015-01-01

The aim of the present study was to examine the apoptotic effect of flavonoids in methanol extracts of Ginkgo biloba fallen leaves (MEGFL) on melanoma cells. Ginkgo biloba is a deciduous castle chaplain and its leaves include various types of flavonoids such as flavonol-O-glycosides. Ginkgo biloba is known to have therapeutic properties against a number of diseases such as cerebrovascular diseases, blood circulation disease and hypertension. In the present study MEGFL exhibited a higher cytotoxic effect on melanoma cells than Ginkgo biloba leaves (MEGL). It was also found that MEGFL induced apoptotic cell death which was characterized by DNA fragmentation. During the cell death process following treatment with MEGFL, the expression of a variety of death-associated proteins including p53, caspase-3, caspase-9, cytochrome c and Bax were analyzed in the cytosol of melanoma cells. MEGFL significantly increased the expression levels of caspase-3, caspase-9 and p53 in a dose-dependent manner. Our results indicate that MEGFL induced apoptotic cell death by increasing the expression of cell death-associated proteins in melanoma cells.

The Core Molecular Machinery Used for Engulfment of Apoptotic Cells Regulates the JNK Pathway Mediating Axon Regeneration in Caenorhabditis elegans.

PubMed

Pastuhov, Strahil Iv; Fujiki, Kota; Tsuge, Anna; Asai, Kazuma; Ishikawa, Sho; Hirose, Kazuya; Matsumoto, Kunihiro; Hisamoto, Naoki

2016-09-14

The mechanisms that govern the ability of specific neurons to regenerate their axons after injury are not well understood. In Caenorhabditis elegans, the initiation of axon regeneration is positively regulated by the JNK-MAPK pathway. In this study, we identify two components functioning upstream of the JNK pathway: the Ste20-related protein kinase MAX-2 and the Rac-type GTPase CED-10. CED-10, when bound by GTP, interacts with MAX-2 and functions as its upstream regulator in axon regeneration. CED-10, in turn, is activated by axon injury via signals initiated from the integrin α-subunit INA-1 and the nonreceptor tyrosine kinase SRC-1 and transmitted via the signaling module CED-2/CrkII-CED-5/Dock180-CED-12/ELMO. This module is also known to regulate the engulfment of apoptotic cells during development. Our findings thus reveal that the molecular machinery used for engulfment of apoptotic cells also promotes axon regeneration through activation of the JNK pathway. The molecular mechanisms of axon regeneration after injury remain poorly understood. In Caenorhabditis elegans, the initiation of axon regeneration is positively regulated by the JNK-MAPK pathway. In this study, we show that integrin, Rac-GTPase, and several other molecules, all of which are known to regulate engulfment of apoptotic cells during development, also regulate axon regeneration. This signaling module activates the JNK-MAPK cascade via MAX-2, a PAK-like protein kinase that binds Rac. Our findings thus reveal that the molecular machinery used for engulfment of apoptotic cells also promotes axon regeneration through activation of the JNK pathway. Copyright © 2016 the authors 0270-6474/16/369710-12$15.00/0.

Taurine protects HK-2 cells from oxidized LDL-induced cytotoxicity via the ROS-mediated mitochondrial and p53-related apoptotic pathways.

PubMed

Chang, Chun-Yu; Shen, Chao-Yu; Kang, Chao-Kai; Sher, Yuh-Pyng; Sheu, Wayne H-H; Chang, Chia-Che; Lee, Tsung-Han

2014-09-15

Oxidized LDL (oxLDL) induces a pro-oxidative environment and promotes apoptosis, causing the progression of renal diseases in humans. Taurine is a semi-essential amino acid in mammals and has been shown to be a potent endogenous antioxidant. The kidney plays a pivotal role in maintaining the balance of taurine. However, the mechanisms underlying the protective effects of taurine against oxLDL-induced injury in renal epithelial cells have not been clarified. In the present study, we investigated the anti-apoptotic effects of taurine on human proximal tubular epithelial (HK-2) cells exposed to oxLDL and explored the related mechanisms. We observed that oxLDL increased the contents of ROS and of malondialdehyde (MDA), which is a lipid peroxidation by-product that acts as an indicator of the cellular oxidation status. In addition, oxLDL induced cell death and apoptosis in HK-2 cells. Pretreatment with taurine at 100 μM significantly attenuated the oxLDL-induced cytotoxicity. We determined that oxLDL triggered the phosphorylation of ERK and, in turn, the activation of p53 and other apoptosis-related events, including calcium accumulation, destabilization of the mitochondrial permeability and disruption of the balance between pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins. The malfunctions induced by oxLDL were effectively blocked by taurine. Thus, our results suggested that taurine exhibits potential therapeutic activity by preventing oxLDL-induced nephrotoxicity. The inhibition of oxLDL-induced epithelial apoptosis by taurine was at least partially due to its anti-oxidant activity and its ability to modulate the ERK and p53 apoptotic pathways. Copyright © 2014 Elsevier Inc. All rights reserved.

Nicotinamide induces mitochondrial-mediated apoptosis through oxidative stress in human cervical cancer HeLa cells.

PubMed

Feng, Yi; Wang, Yonghua; Jiang, Chengrui; Fang, Zishui; Zhang, Zhiqiang; Lin, Xiaoying; Sun, Liwei; Jiang, Weiying

2017-07-15

Nicotinamide participates in energy metabolism and influences cellular redox status and modulates multiple pathways related with both cellular survival and death. Recent studies have shown that it induced proliferation inhibition and apoptosis in many cancer cells. However, little is known about the effects of nicotinamide on human cervical cancer cells. We aimed to evaluate the effects of the indicated concentrations nicotinamide on cell proliferation, apoptosis and redox-related parameters in HeLa cells and investigated the apoptotic mechanism. After the treatment of the indicated concentrations nicotinamide, HeLa cell proliferation was evaluated by the CCK-8 assay and the production of ROS (reactive oxygen species) was measured using 2',7'-Dichlorofluorescin diacetate. The apoptotic effect was confirmed by observing the cellular and nuclear morphologies with fluorescence microscope and apoptotic rate of HeLa cell apoptosis was measured by flow cytometry using Annexin-V method. Moreover, we examined the mitochondrial membrane potential by JC-1 method and measured the expression of apoptosis related genes using qRT-PCR and immunoblotting. Nicotinamide restrained the HeLa cell proliferation and significantly increased the accumulation of ROS and depletion of GSH at relatively high concentrations. Furthermore, nicotinamide promoted HeLa cell apoptosis via the intrinsic mitochondrial apoptotic pathway. Our study revealed that nicotinamide induced the apoptosis through oxidative stress and intrinsic mitochondrial apoptotic pathways in HeLa cell. The results emerge that nicotinamide may be an inexpensive, safe and promising therapeutic agent or a neoadjuvant chemotherapy for cervical cancer patients, as well useful to find new drugs for cervical cancer therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

Apoptotic function of human PMS2 compromised by the nonsynonymous single-nucleotide polymorphic variant R20Q

PubMed Central

Marinovic-Terzic, Ivana; Yoshioka-Yamashita, Atsuko; Shimodaira, Hideki; Avdievich, Elena; Hunton, Irina C.; Kolodner, Richard D.; Edelmann, Winfried; Wang, Jean Y. J.

2008-01-01

Mismatch repair (MMR) corrects replication errors during DNA synthesis. The mammalian MMR proteins also activate cell cycle checkpoints and apoptosis in response to persistent DNA damage. MMR-deficient cells are resistant to cisplatin, a DNA cross-linking agent used in chemotherapy, because of impaired activation of apoptotic pathways. It is shown that postmeiotic segregation 2 (PMS2), an MMR protein, is required for cisplatin-induced activation of p73, a member of the p53 family of transcription factors with proapoptotic activity. The human PMS2 is highly polymorphic, with at least 12 known nonsynonymous codon changes identified. We show here that the PMS2(R20Q) variant is defective in activating p73-dependent apoptotic response to cisplatin. When expressed in Pms2-deficient mouse fibroblasts, human PMS2(R20Q) but not PMS2 interfered with the apoptotic response to cisplatin. Correspondingly, PMS2 but not PMS2(R20Q) enhanced the cytotoxic effect of cisplatin measured by clonogenic survival. Because PMS2(R20Q) lacks proapoptotic activity, this polymorphic allele may modulate tumor responses to cisplatin among cancer patients. PMID:18768816

Apoptotic function of human PMS2 compromised by the nonsynonymous single-nucleotide polymorphic variant R20Q.

PubMed

Marinovic-Terzic, Ivana; Yoshioka-Yamashita, Atsuko; Shimodaira, Hideki; Avdievich, Elena; Hunton, Irina C; Kolodner, Richard D; Edelmann, Winfried; Wang, Jean Y J

2008-09-16

Mismatch repair (MMR) corrects replication errors during DNA synthesis. The mammalian MMR proteins also activate cell cycle checkpoints and apoptosis in response to persistent DNA damage. MMR-deficient cells are resistant to cisplatin, a DNA cross-linking agent used in chemotherapy, because of impaired activation of apoptotic pathways. It is shown that postmeiotic segregation 2 (PMS2), an MMR protein, is required for cisplatin-induced activation of p73, a member of the p53 family of transcription factors with proapoptotic activity. The human PMS2 is highly polymorphic, with at least 12 known nonsynonymous codon changes identified. We show here that the PMS2(R20Q) variant is defective in activating p73-dependent apoptotic response to cisplatin. When expressed in Pms2-deficient mouse fibroblasts, human PMS2(R20Q) but not PMS2 interfered with the apoptotic response to cisplatin. Correspondingly, PMS2 but not PMS2(R20Q) enhanced the cytotoxic effect of cisplatin measured by clonogenic survival. Because PMS2(R20Q) lacks proapoptotic activity, this polymorphic allele may modulate tumor responses to cisplatin among cancer patients.

Pharmacological Prevention and Reversion of Erectile Dysfunction after Radical Prostatectomy, By Modulation of Nitric Oxide/Cgmp Pathways

DTIC Science & Technology

2008-03-01

Figure 3. Time course of the effect of bilateral cavernosal nerve resection on the smooth muscle cell content in the rat corpora cavernosa. Penile...iindicates the apoptotic cells in the corpora cavernosa. Bottom: QIA for TUNEL ***Pɘ.001 Figure 7: Time course of the effect of bilateral...Figure 6 Effect of unilateral and bilateral cavernosal nerve resection and long-term sildenafil treatment on cell proliferation and turnover in the

The oncogenic tyrosine kinase Lyn impairs the pro-apoptotic function of Bim.

PubMed

Aira, Lazaro E; Villa, Elodie; Colosetti, Pascal; Gamas, Parvati; Signetti, Laurie; Obba, Sandrine; Proics, Emma; Gautier, Fabien; Bailly-Maitre, Béatrice; Jacquel, Arnaud; Robert, Guillaume; Luciano, Frédéric; Juin, Philippe P; Ricci, Jean-Ehrland; Auberger, Patrick; Marchetti, Sandrine

2018-04-01

Phosphorylation of Ser/Thr residues is a well-established modulating mechanism of the pro-apoptotic function of the BH3-only protein Bim. However, nothing is known about the putative tyrosine phosphorylation of this Bcl-2 family member and its potential impact on Bim function and subsequent Bax/Bak-mediated cytochrome c release and apoptosis. As we have previously shown that the tyrosine kinase Lyn could behave as an anti-apoptotic molecule, we investigated whether this Src family member could directly regulate the pro-apoptotic function of Bim. In the present study, we show that Bim is phosphorylated onto tyrosine residues 92 and 161 by Lyn, which results in an inhibition of its pro-apoptotic function. Mechanistically, we show that Lyn-dependent tyrosine phosphorylation of Bim increases its interaction with anti-apoptotic members such as Bcl-xL, therefore limiting mitochondrial outer membrane permeabilization and subsequent apoptosis. Collectively, our data uncover one molecular mechanism through which the oncogenic tyrosine kinase Lyn negatively regulates the mitochondrial apoptotic pathway, which may contribute to the transformation and/or the chemotherapeutic resistance of cancer cells.

Taurine ameliorated homocysteine-induced H9C2 cardiomyocyte apoptosis by modulating endoplasmic reticulum stress.

PubMed

Zhang, Zhimin; Zhao, Lianyou; Zhou, Yanfen; Lu, Xuanhao; Wang, Zhengqiang; Wang, Jipeng; Li, Wei

2017-05-01

Homocysteine (Hcy)-triggered endoplasmic reticulum (ER) stress-mediated endothelial cell apoptosis has been suggested as a cause of Hcy-dependent vascular injury. However, whether ER stress is the molecular mechanism linking Hcy and cardiomyocytes death is unclear. Taurine has been reported to exert cardioprotective effects via various mechanisms. However, whether taurine protects against Hcy-induced cardiomyocyte death by attenuating ER stress is unknown. This study aimed to evaluate the opposite effects of taurine on Hcy-induced cardiomyocyte apoptosis and their underlying mechanisms. Our results demonstrated that low-dose or short-term Hcy treatment increased the expression of glucose-regulated protein 78 (GRP78) and activated protein kinase RNA-like ER kinase (PERK), inositol-requiring enzyme 1 (IRE1), and activating transcription factor 6 (ATF6), which in turn prevented apoptotic cell death. High-dose Hcy or prolonged Hcy treatment duration significantly up-regulated levels of C/EBP homologous protein (CHOP), cleaved caspase-12, p-c-Jun N-terminal kinase (JNK), and then triggered apoptotic events. High-dose Hcy also resulted in a decrease in mitochondrial membrane potential (Δψm) and an increase in cytoplasmic cytochrome C and the expression of cleaved caspase-9. Pretreatment of cardiomyocytes with sodium 4-phenylbutyric acid (an ER stress inhibitor) significantly inhibited Hcy-induced apoptosis. Furthermore, blocking the PERK pathway partly alleviated Hcy-induced ER stress-modulated cardiomyocyte apoptosis, and down-regulated the levels of Bax and cleaved caspase-3. Experimental taurine pretreatment inhibited the expression of ER stress-related proteins, and protected against apoptotic events triggered by Hcy-induced ER stress. Taken together, our results suggest that Hcy triggered ER stress in cardiomyocytes, which was the crucial molecular mechanism mediating Hcy-induced cardiomyocyte apoptosis, and the adverse effect of Hcy could be prevented by taurine.

Improved bioavailability of targeted Curcumin delivery efficiently regressed cardiac hypertrophy by modulating apoptotic load within cardiac microenvironment.

PubMed

Ray, Aramita; Rana, Santanu; Banerjee, Durba; Mitra, Arkadeep; Datta, Ritwik; Naskar, Shaon; Sarkar, Sagartirtha

2016-01-01

Cardiomyocyte apoptosis acts as a prime modulator of cardiac hypertrophy leading to heart failure, a major cause of human mortality worldwide. Recent therapeutic interventions have focussed on translational applications of diverse pharmaceutical regimes among which, Curcumin (from Curcuma longa) is known to have an anti-hypertrophic potential but with limited pharmacological efficacies due to low aqueous solubility and poor bioavailability. In this study, Curcumin encapsulated by carboxymethyl chitosan (CMC) nanoparticle conjugated to a myocyte specific homing peptide was successfully delivered in bioactive form to pathological myocardium for effective regression of cardiac hypertrophy in a rat (Rattus norvegicus) model. Targeted nanotization showed higher cardiac bioavailability of Curcumin at a low dose of 5 mg/kg body weight compared to free Curcumin at 35 mg/kg body weight. Moreover, Curcumin/CMC-peptide treatment during hypertrophy significantly improved cardiac function by downregulating expression of hypertrophy marker genes (ANF, β-MHC), apoptotic mediators (Bax, Cytochrome-c) and activity of apoptotic markers (Caspase 3 and PARP); whereas free Curcumin in much higher dose showed minimal improvement during compromised cardiac function. Targeted Curcumin treatment significantly lowered p53 expression and activation in diseased myocardium via inhibited interaction of p53 with p300-HAT. Thus attenuated acetylation of p53 facilitated p53 ubiquitination and reduced the apoptotic load in hypertrophied cardiomyocytes; thereby limiting cardiomyocytes' need to enter the regeneration cycle during hypertrophy. This study elucidates for the first time an efficient targeted delivery regimen for Curcumin and also attributes towards probable mechanistic insight into its therapeutic potential as a cardio-protective agent for regression of cardiac hypertrophy. Copyright © 2015 Elsevier Inc. All rights reserved.

Silencing of cytosolic NADP(+)-dependent isocitrate dehydrogenase by small interfering RNA enhances the sensitivity of HeLa cells toward staurosporine.

PubMed

Lee, Su-Min; Park, Sin Young; Shin, Seoung Woo; Kil, In Sup; Yang, Eun Sun; Park, Jeen-Woo

2009-02-01

Staurosporine induces the production of reactive oxygen species, which play an important causative role in apoptotic cell death. Recently, it was demonstrated that the control of cellular redox balance and the defense against oxidative damage is one of the primary functions of cytosolic NADP(+)-dependent isocitrate dehydrogenase (IDPc) by supplying NADPH for antioxidant systems. The present report shows that silencing of IDPc expression in HeLa cells greatly enhances apoptosis induced by staurosporine. Transfection of HeLa cells with an IDPc small interfering RNA (siRNA) markedly decreased activity of IDPc, enhancing the susceptibility of staurosporine-induced apoptosis reflected by DNA fragmentation, cellular redox status and the modulation of apoptotic marker proteins. These results indicate that IDPc may play an important role in regulating the apoptosis induced by staurosporine and the sensitizing effect of IDPc siRNA on the apoptotic cell death of HeLa cells offers the possibility of developing a modifier of cancer chemotherapy.

Apoptotic cell death during Drosophila oogenesis is differentially increased by electromagnetic radiation depending on modulation, intensity and duration of exposure.

PubMed

Sagioglou, Niki E; Manta, Areti K; Giannarakis, Ioannis K; Skouroliakou, Aikaterini S; Margaritis, Lukas H

2016-01-01

Present generations are being repeatedly exposed to different types and doses of non-ionizing radiation (NIR) from wireless technologies (FM radio, TETRA and TV stations, GSM and UMTS phones/base stations, Wi-Fi networks, DECT phones). Although there is controversy on the published data regarding the non-thermal effects of NIR, studies have convincingly demonstrated bioeffects. Their results indicate that modulation, intensity, exposure duration and model system are important factors determining the biological response to irradiation. Attempting to address the dependence of NIR bioeffectiveness on these factors, apoptosis in the model biological system Drosophila melanogaster was studied under different exposure protocols. A signal generator was used operating alternatively under Continuous Wave (CW) or Frequency Modulation (FM) emission modes, at three power output values (10 dB, 0, -10 dB), under four carrier frequencies (100, 395, 682, 900 MHz). Newly emerged flies were exposed either acutely (6 min or 60 min on the 6th day), or repeatedly (6 min or 60 min daily for the first 6 days of their life). All exposure protocols resulted in an increase of apoptotic cell death (ACD) observed in egg chambers, even at very low electric field strengths. FM waves seem to have a stronger effect in ACD than continuous waves. Regarding intensity and temporal exposure pattern, EMF-biological tissue interaction is not linear in response. Intensity threshold for the induction of biological effects depends on frequency, modulation and temporal exposure pattern with unknown so far mechanisms. Given this complexity, translating such experimental data into possible human exposure guidelines is yet arbitrary.

Hesperidin Induces Apoptosis by Inhibiting Sp1 and Its Regulatory Protein in MSTO-211H Cells

PubMed Central

Lee, Kyung-Ae; Lee, Sang-Han; Lee, Yong-Jin; Baeg, Seung Mi; Shim, Jung-Hyun

2012-01-01

Hesperidin, a flavanone present in citrus fruits, has been studied as potential therapeutic agents that have anti-tumor activity and apoptotic effects in several cancers, but there is no report about the apoptotic effect of hesperidin in human malignant pleural mesothelioma through the specificity protein 1 (Sp1) protein. We investigated whether hesperidin inhibited cell growth and regulated Sp1 target proteins by suppressing the levels of Sp1 protein in MSTO-211H cells. The IC50 value of hesperidin was determined to be 152.3 μM in MSTO-211H cells for 48 h. Our results suggested that hesperidin (0-160 μM) decreased cell viability, and induced apoptotic cell death. Hesperidin increased Sub-G1 population in MSTO-211H cells. Hesperidin significantly suppressed mRNA/protein level of Sp1 and modulated the expression level of the Sp1 regulatory protein such as p27, p21, cyclin D1, Mcl-1, and survivin in mesothelioma cells. Also, hesperidin induced apoptotic signaling including: cleavages of Bid, caspase-3, and PARP, upregulation of Bax, and down-regulation of Bcl-xl in mesothelioma cells. These results show that hesperidin suppressed mesothelioma cell growth through inhibition of Sp1. In this study, we demonstrated that Sp1 acts as a novel molecular target of hesperidin in human malignant pleural mesothelioma. PMID:24130923

Gonadal steroids modulate Fas-induced apoptosis of lactotropes and somatotropes.

PubMed

Jaita, Gabriela; Zárate, Sandra; Ferrari, Luciana; Radl, Daniela; Ferraris, Jimena; Eijo, Guadalupe; Zaldivar, Verónica; Pisera, Daniel; Seilicovich, Adriana

2011-02-01

We have previously reported that Fas activation induces apoptosis of anterior pituitary cells from rats at proestrus but not at diestrus and in an estrogen-dependent manner. In this study, we evaluated the effect of Fas activation on apoptosis of lactotropes and somatotropes during the estrous cycle and explored the action of gonadal steroids on Fas-induced apoptosis. Also, we studied whether changes in Fas expression are involved in the apoptotic response of anterior pituitary cells. Fas activation increased the percentage of TUNEL-positive lactotropes and somatotropes at proestrus but not at diestrus. FasL triggered apoptosis of somatotropes only when cells from ovariectomized rats were cultured in the presence of 17 β-estradiol (E2). Progesterone (P4) blocked the apoptotic action of the Fas/FasL system in lactotropes and somatotropes incubated with E2. Both E2 and P4 increased the percentage of cells expressing Fas at the cell membrane. Our results show that Fas activation induces apoptosis of lactotropes and somatotropes at proestrus but not at diestrus. Gonadal steroids may be involved in the apoptotic response of lactotropes and somatotropes, suggesting that Fas activation is implicated in the renewal of these pituitary subpopulations during the estrous cycle. The effect of gonadal steroids on Fas expression may be only partially involved in regulation of the Fas/FasL apoptotic pathway in the anterior pituitary gland.

A Review on Structures and Functions of Bcl-2 Family Proteins from Homo sapiens.

PubMed

Sivakumar, Dakshinamurthy; Sivaraman, Thirunavukkarasu

2016-01-01

Cancer cells evade apoptosis, which is regulated by proteins of Bcl-2 family in the intrinsic pathways. Numerous experimental three-dimensional (3D) structures of the apoptotic proteins and the proteins bound with small chemical molecules/peptides/proteins have been reported in the literature. In this review article, the 3D structures of the Bcl-2 family proteins from Homo sapiens and as well complex structures of the anti-apoptotic proteins bound with small molecular inhibitors reported in the literature to date have been comprehensively listed out and described in detail. Moreover, the molecular mechanisms by which the Bcl-2 family proteins modulate the apoptotic processes and strategies for designing antagonists to anti-apoptotic proteins have been concisely discussed.

Cell life and death in the anterior pituitary gland: role of oestrogens.

PubMed

Seilicovich, A

2010-07-01

Apoptotic processes play an important role in the maintenance of cell numbers in the anterior pituitary gland during physiological endocrine events. In this review, we summarise the regulation of apoptosis of anterior pituitary cells, particularly lactotrophs, somatotrophs and gonadotrophs, and analyse the possible mechanisms involved in oestrogen-induced apoptosis in anterior pituitary cells. Oestrogens exert apoptotic actions in several cell types and act as modulators of pituitary cell renewal, sensitising cells to both mitogenic and apoptotic signals. Local synthesis of growth factors and cytokines induced by oestradiol as well as changes in phenotypic features that enhance the responsiveness of anterior pituitary cells to pro-apoptotic factors may account for cyclical apoptotic activity in anterior pituitary cells during the oestrous cycle. Considering that tissue homeostasis results from a balance between cell proliferation and death and that mechanisms involved in apoptosis are tightly regulated, defects in cell death processes could have a considerable physiopathological impact.

Air pollution induces enhanced mitochondrial oxidative stress in cystic fibrosis airway epithelium.

PubMed

Kamdar, O; Le, Wei; Zhang, J; Ghio, A J; Rosen, G D; Upadhyay, D

2008-10-29

We studied the effects of airborne particulate matters (PM) on cystic fibrosis (CF) epithelium. We noted that PM enhanced human CF bronchial epithelial apoptosis, activated caspase-9 and PARP-1; and reduced mitochondrial membrane potential. Mitochondrial inhibitors (4,4-diisothiocyanatostilbene-2,2'disulfonic acid, rotenone and thenoyltrifluoroacetone) blocked PM-induced generation of reactive oxygen species and apoptosis. PM upregulated pro-apoptotic Bad, Bax, p53 and p21; and enhanced mitochondrial localization of Bax. The anti-apoptotic Bcl-2, Bcl-xl, Mcl-1 and Xiap remained unchanged; however, overexpression of Bcl-xl blocked PM-induced apoptosis. Accordingly, we provide the evidence that PM enhances oxidative stress and mitochondrial signaling mediated apoptosis via the modulation of Bcl family proteins in CF.

36 kDa glycoprotein isolated from Rhus verniciflua stokes inhibits G/GO-induced mitochondrial apoptotic signal pathways in BNL CL.2 cells.

PubMed

Lee, Sei-Jung; Oh, Phil-Sun; Lim, Kwang; Lim, Kye-Taek

2005-12-01

Rhus verniciflua Stokes is one of the medicinal plants traditionally used to heal and treat hepatic and inflammatory diseases. We found that a glycoprotein isolated from the fruit has a molecular weight of 36 kDa and consists of a carbohydrate component (38.75%) and a protein (61.25%), and that the glycoprotein has a strong scavenging activity against hydroxyl radicals without any pro-oxidant activity in the cell-free system. In glucose/glucose oxidase (G/GO)-induced BNL CL.2 cells, the results showed that Rhus verniciflua Stokes glycoprotein has dose-dependent blocking activities against G/GO-induced cytotoxicity and apoptosis, increasing the glutathione (GSH) peroxidase activity. In the activity of the mitochondrial apoptotic mediators (cytochrome c, caspases and poly(ADP-ribose)polymerase (PARP)), the glycoprotein (100 microg/ml) showed an inhibitory effect on cytochrome c release, caspase-9/3 activation, and PARP cleavage. Moreover, Rhus verniciflua Stokes glycoprotein has a stimulating effect on the nitric oxide production. Here, we speculate that this glycoprotein is one of the natural antioxidants and of the modulators of apoptotic signal pathways in BNL CL.2 cells.

Versican G3 Domain Modulates Breast Cancer Cell Apoptosis: A Mechanism for Breast Cancer Cell Response to Chemotherapy and EGFR Therapy

PubMed Central

Du, William Weidong; Yang, Burton B.; Yang, Bing L.; Deng, Zhaoqun; Fang, Ling; Shan, Sze Wan; Jeyapalan, Zina; Zhang, Yaou; Seth, Arun; Yee, Albert J.

2011-01-01

Overexpression of EGFR and versican has been reported in association with breast cancers. Considered oncogenic, these molecules may be attractive therapeutic targets. Possessing anti-apoptotic and drug resistant properties, overexpression of these molecules is accompanied by selective sensitization to the process of apoptosis. In this study, we exogenously expressed a versican G3 construct in breast cancer cell lines and analyzed the effects of G3 on cell viability in fetal bovine serum free conditioned media and evaluated the effects of apoptotic agent C2-ceramide, and chemotherapeutic agents including Docetaxel, Doxorubicin, and Epirubicin. Versican G3 domain enhanced tumor cell resistance to apoptosis when cultured in serum free medium, Doxorubicin, or Epirubicin by up-regulating pERK and GSK-3β (S9P). However, it could be prevented by selective EGFR inhibitor AG 1478 and selective MEK inhibitor PD 98059. Both AG 1478 and PD 98059 enhanced expression of pSAPK/JNK, while selective JNK inhibitor SP 600125 enhanced expression of GSK-3β (S9P). Versican G3 promoted cell apoptosis induced by C2-ceramide or Docetaxel by enhancing expression of pSAPK/JNK and decreasing expression of GSK-3β (S9P), an observation blocked by AG 1478 or SP 6000125. Inhibition of endogenous versican expression by siRNA or reduction of versican G3's expression by linking G3 with 3′UTR prevented G3 modulated cell apoptosis. The dual roles of G3 in modulating breast cancer cell resistance to chemotherapeutic agents may in part explain a potential mechanism for breast cancer cell resistance to chemotherapy and EGFR therapy. The apoptotic effects of chemotherapeutics depend upon the activation and balance of down stream signals in the EGFR pathway. GSK-3β (S9P) appears to function as a key checkpoint in this balance of apoptosis and anti-apoptosis. Investigation and potential consideration of targeting GSK-3β (S9P) merits further study. PMID:22096483

Versican G3 domain modulates breast cancer cell apoptosis: a mechanism for breast cancer cell response to chemotherapy and EGFR therapy.

PubMed

Du, William Weidong; Yang, Burton B; Yang, Bing L; Deng, Zhaoqun; Fang, Ling; Shan, Sze Wan; Jeyapalan, Zina; Zhang, Yaou; Seth, Arun; Yee, Albert J

2011-01-01

Overexpression of EGFR and versican has been reported in association with breast cancers. Considered oncogenic, these molecules may be attractive therapeutic targets. Possessing anti-apoptotic and drug resistant properties, overexpression of these molecules is accompanied by selective sensitization to the process of apoptosis. In this study, we exogenously expressed a versican G3 construct in breast cancer cell lines and analyzed the effects of G3 on cell viability in fetal bovine serum free conditioned media and evaluated the effects of apoptotic agent C2-ceramide, and chemotherapeutic agents including Docetaxel, Doxorubicin, and Epirubicin. Versican G3 domain enhanced tumor cell resistance to apoptosis when cultured in serum free medium, Doxorubicin, or Epirubicin by up-regulating pERK and GSK-3β (S9P). However, it could be prevented by selective EGFR inhibitor AG 1478 and selective MEK inhibitor PD 98059. Both AG 1478 and PD 98059 enhanced expression of pSAPK/JNK, while selective JNK inhibitor SP 600125 enhanced expression of GSK-3β (S9P). Versican G3 promoted cell apoptosis induced by C2-ceramide or Docetaxel by enhancing expression of pSAPK/JNK and decreasing expression of GSK-3β (S9P), an observation blocked by AG 1478 or SP 6000125. Inhibition of endogenous versican expression by siRNA or reduction of versican G3's expression by linking G3 with 3'UTR prevented G3 modulated cell apoptosis. The dual roles of G3 in modulating breast cancer cell resistance to chemotherapeutic agents may in part explain a potential mechanism for breast cancer cell resistance to chemotherapy and EGFR therapy. The apoptotic effects of chemotherapeutics depend upon the activation and balance of down stream signals in the EGFR pathway. GSK-3β (S9P) appears to function as a key checkpoint in this balance of apoptosis and anti-apoptosis. Investigation and potential consideration of targeting GSK-3β (S9P) merits further study.

Study of morphological changes in breast cancer cells MCF-7 under the action of pro-apoptotic agents with laser modulation interference microscope MIM-340

NASA Astrophysics Data System (ADS)

Nebogatikov, V.; Nikitiuk, A.; Konysheva, A.; Ignatyev, P.; Grishko, V.; Naimark, O.

2017-09-01

Quantitative phase microscopy is a new method to measure and evaluate the microlevel processes characterized by the high resolution and providing ample opportunities to quantitatively analyze various parameters, including specimens from biological matter. In this study, a laser interference microscope was used to evaluate the state of cancer cells (living and apoptotic). Apoptotic cancer cells were obtained by treatment of MCF-7 cells with the use of betulin-based α-bromomethyl ketone (BMK) derivative. When using the microscope, the main differences in the morphometric parameters of living and apoptotic cells such as height, diameter, perimeter, area and volume were appraised. The criteria that can be used as markers of apoptosis activation were identified.

Inhibition of Carbonic Anhydrase IX by Ureidosulfonamide Inhibitor U104 Reduces Prostate Cancer Cell Growth, But Does Not Modulate Daunorubicin or Cisplatin Cytotoxicity.

PubMed

Riemann, Anne; Güttler, Antje; Haupt, Verena; Wichmann, Henri; Reime, Sarah; Bache, Matthias; Vordermark, Dirk; Thews, Oliver

2018-03-05

Carbonic anhydrase (CA) IX has emerged as a promising target for cancer therapy. It is highly upregulated in hypoxic regions and mediates pH regulation critical for tumor cell survival as well as extracellular acidification of the tumor microenvironment, which promotes tumor aggressiveness via various mechanisms, such as augmenting metastatic potential. Therefore, the aim of this study was to analyze the complex interdependency between CA IX and the tumor microenvironment in prostate tumor cells with regard to potential therapeutic implications. CA IX was upregulated by hypoxia as well as acidosis in prostate cancer cells. This induction did not modulate intracellular pH but led to extracellular acidification. Pharmacological inhibition of CA IX activity by U104 (SLC-0111) resulted in a reduction in tumor cell growth and an increase in apoptotic cell death. Intracellular pH was reduced under normoxic and even more so under hypoxic conditions when CA IX level was high. However, although intracellular pH regulation was disturbed, targeting CA IX in combination with daunorubicin or cisplatin did not intensify apoptotic tumor cell death. Hence, targeting CA IX in prostate cancer cells can lead to intracellular pH dysregulation and, consequently, can reduce cellular growth and elevate apoptotic cell death. Attenuation of extracellular acidification by blocking CA IX might additionally impede tumor progression and metastasis. However, no beneficial effect was seen when targeting CA IX in combination with chemotherapeutic drugs.

Enhancement of UVB radiation-mediated apoptosis by knockdown of cytosolic NADP+-dependent isocitrate dehydrogenase in HaCaT cells.

PubMed

Lee, Su Jeong; Park, Jeen-Woo

2014-04-01

Ultraviolet B (UVB) radiation induces the production of reactive oxygen species (ROS) that promote apoptotic cell death. We showed that cytosolic NADP+-dependent isocitrate dehydrogenase (IDPc) plays an essential role in the control of cellular redox balance and defense against oxidative damage, by supplying NADPH for antioxidant systems. In this study, we demonstrated that knockdown of IDPc expression by RNA interference enhances UVB-induced apoptosis of immortalized human HaCaT keratinocytes. This effect manifested as DNA fragmentation, changes in cellular redox status, mitochondrial dysfunction, and modulation of apoptotic marker expression. Based on our findings, we suggest that attenuation of IDPc expression may protect skin from UVB-mediated damage, by inducing the apoptosis of UV-damaged cells.

Ethanol Influences on Bax Translocation, Mitochondrial Membrane Potential, and Reactive Oxygen Species Generation are Modulated by Vitamin E and Brain-Derived Neurotrophic Factor

PubMed Central

Heaton, Marieta Barrow; Paiva, Michael; Siler-Marsiglio, Kendra

2011-01-01

Background This study investigated ethanol influences on intracellular events which predispose developing neurons toward apoptosis, and the capacity of the antioxidant α-tocopherol (vitamin E) and the neurotrophin brain-derived neurotrophic factor (BDNF) to modulate these effects. Assessments were made of the following: (1) ethanol-induced translocation of the pro-apoptotic Bax protein to the mitochondrial membrane, a key upstream event in the initiation of apoptotic cell death; (2) disruption of the mitochondrial membrane potential (MMP) as a result of ethanol exposure, an important process in triggering the apoptotic cascade; and (3) generation of damaging reactive oxygen species (ROS) as a function of ethanol exposure. Methods These interactions were investigated in cultured postnatal day 8 neonatal rat cerebellar granule cells, a population vulnerable to developmental ethanol exposure in vivo and in vitro. Bax mitochondrial translocation was analyzed via subcellular fractionation followed by Western blot, and mitochondrial membrane integrity was determined using the lipophilic dye, JC-1, which exhibits potential-dependent accumulation in the mitochondrial membrane as a function of the MMP. Results Brief ethanol exposure in these preparations precipitated Bax translocation, but both vitamin E and BDNF reduced this effect to control levels. Ethanol treatment also resulted in a disturbance of the MMP, and this effect was blunted by the antioxidant and the neurotrophin. ROS generation was enhanced by a short ethanol exposure in these cells, but the production of these harmful free radicals was diminished to control levels by co-treatment with either vitamin E or BDNF. Conclusions These results indicate that both antioxidants and neurotrophic factors have the potential to ameliorate ethanol neurotoxicity, and suggest possible interventions which could be implemented in preventing or lessening the severity of the damaging effects of ethanol in the developing central nervous system seen in the fetal alcohol syndrome (FAS). PMID:21332533

The anti-apoptotic BAG3 protein is involved in BRAF inhibitor resistance in melanoma cells.

PubMed

Guerriero, Luana; Palmieri, Giuseppe; De Marco, Margot; Cossu, Antonio; Remondelli, Paolo; Capunzo, Mario; Turco, Maria Caterina; Rosati, Alessandra

2017-10-06

BAG3 protein, a member of BAG family of co-chaperones, has a pro-survival role in several tumour types. BAG3 anti-apoptotic properties rely on its characteristic to bind several intracellular partners, thereby modulating crucial events such as apoptosis, differentiation, cell motility, and autophagy. In human melanomas, BAG3 positivity is correlated with the aggressiveness of the tumour cells and can sustain IKK-γ levels, allowing a sustained activation of NF-κB. Furthermore, BAG3 is able to modulate BRAFV600E levels and activity in thyroid carcinomas. BRAFV600E is the most frequent mutation detected in malignant melanomas and is targeted by Vemurafenib, a specific inhibitor found to be effective in the treatment of advanced melanoma. However, patients with BRAF-mutated melanoma may result insensitive ab initio or, mostly, develop acquired resistance to the treatment with this molecule. Here we show that BAG3 down-modulation interferes with BRAF levels in melanoma cells and sensitizes them to Vemurafenib treatment. Furthermore, the down-modulation of BAG3 protein in an in vitro model of acquired resistance to Vemurafenib can induce sensitization to the BRAFV600E specific inhibition by interfering with BRAF pathway through reduction of ERK phosphorylation, but also on parallel survival pathways. Future studies on BAG3 molecular interactions with key proteins responsible of acquired BRAF inhibitor resistance may represent a promising field for novel multi-drugs treatment design.

The anti-apoptotic BAG3 protein is involved in BRAF inhibitor resistance in melanoma cells

PubMed Central

Guerriero, Luana; Palmieri, Giuseppe; De Marco, Margot; Cossu, Antonio; Remondelli, Paolo; Capunzo, Mario; Turco, Maria Caterina; Rosati, Alessandra

2017-01-01

BAG3 protein, a member of BAG family of co-chaperones, has a pro-survival role in several tumour types. BAG3 anti-apoptotic properties rely on its characteristic to bind several intracellular partners, thereby modulating crucial events such as apoptosis, differentiation, cell motility, and autophagy. In human melanomas, BAG3 positivity is correlated with the aggressiveness of the tumour cells and can sustain IKK-γ levels, allowing a sustained activation of NF-κB. Furthermore, BAG3 is able to modulate BRAFV600E levels and activity in thyroid carcinomas. BRAFV600E is the most frequent mutation detected in malignant melanomas and is targeted by Vemurafenib, a specific inhibitor found to be effective in the treatment of advanced melanoma. However, patients with BRAF-mutated melanoma may result insensitive ab initio or, mostly, develop acquired resistance to the treatment with this molecule. Here we show that BAG3 down-modulation interferes with BRAF levels in melanoma cells and sensitizes them to Vemurafenib treatment. Furthermore, the down-modulation of BAG3 protein in an in vitro model of acquired resistance to Vemurafenib can induce sensitization to the BRAFV600E specific inhibition by interfering with BRAF pathway through reduction of ERK phosphorylation, but also on parallel survival pathways. Future studies on BAG3 molecular interactions with key proteins responsible of acquired BRAF inhibitor resistance may represent a promising field for novel multi-drugs treatment design. PMID:29113311

AAV delivery of GRP78/BiP promotes adaptation of human RPE cell to ER stress.

PubMed

Ghaderi, Shima; Ahmadian, Shahin; Soheili, Zahra-Soheila; Ahmadieh, Hamid; Samiei, Shahram; Kheitan, Samira; Pirmardan, Ehsan R

2018-02-01

Adeno associated virus (AAV)-mediated gene delivery of GRP78 (78 kDa glucose-regulated protein) attenuates the condition of endoplasmic reticulum (ER) stress and prevents apoptotic loss of photoreceptors in Retinitis pigmentosa (RP) rats. In the current study we overexpressed Grp78 with the help of AAV-2 in primary human retinal pigmented epithelium (hRPE) cell cultures and examined its effect on cell response to ER stress. The purpose of this work was studying potential stimulating effect of GRP78 on adaptation/pro-survival of hRPE cells under ER stress, as an in vitro model for RPE degeneration. To investigate the effect of Grp78 overexpression on unfolded protein response (UPR) markers under ER stress, hRPE primary cultures were transduced by recombinant virus rAAV/Grp78, and treated with ER stressor drug, tunicamycin. Expression changes of four UPR markers including GRP78, PERK, ATF6α, and GADD153/CHOP, were assessed by real-time PCR and western blotting. We found that GRP78 has a great contribution in modulation of UPR markers to favor adaptive response in ER-stressed hRPE cells. In fact, GRP78 overexpression affected adaptation and apoptotic phases of early UPR, through enhancement of two master regulators/ER stress sensors (PERK and ATF6α) and down-regulation of a key pro-apoptotic cascade activator (GADD153/CHOP). Together these findings demonstrate the promoting effect of GRP78 on adaptation/pro-survival of hRPE cells under ER stress. This protein with anti-apoptotic actions in the early UPR and important role in cell fate regulation, can be recruited as a useful candidate for future investigations of RPE degenerative diseases. © 2017 Wiley Periodicals, Inc.

Losartan protects against cerebral ischemia/reperfusion-induced apoptosis through β-arrestin1-mediated phosphorylation of Akt.

PubMed

Chen, Lin; Ren, Zhiping; Wei, Xinbing; Wang, Shuaishuai; Wang, Yimeng; Cheng, Yanyan; Gao, Hua; Liu, Huiqing

2017-11-15

Losartan, an angiotensin (Ang) II type 1 receptor blocker (ARB), has been revealed to protect against cerebral ischemia/reperfusion (I/R) injury. However, the mechanism by which losartan protect brain ischemia injury is still obscure. In this study, we investigated whether losartan protected against cerebral I/R injury by reducing apoptosis and the possible signaling pathways. Wistar rats were pretreated for 14 days with 5mg/kg losartan, and then subjected to middle cerebral artery occlusion (MCAO) for 2h followed by reperfusion. Meanwhile, PC12 cells pretreated with losartan were exposed to oxygen-glucose deprivation-reoxygenation (OGD/R), an in vitro model of cerebral ischemia. Our results showed that administration of losartan significantly inhibited the apoptosis by decreasing the number of apoptotic cells, decreasing the protein level of cleaved caspase-3, cytochrom C and Bax, and increasing the level of Bcl-2 both in vivo and in vitro. Moreover, losartan treatment markedly enhanced the phosphorylation of Akt and blockade of PI3K activity by wortmannin dramatically inhibited Akt phosphorylation and attenuated the anti-apoptotic effect of losartan. Furthermore, pretreatment with losartan significantly increased the protein level of β-arrestin1 and silence of β-arrestin1 by siRNA partly attenuated losartan-induced anti-apoptotic effect and the phosphorylation of Akt. These results suggested that β-arrestin1 modulated the activation of Akt in losartan-induced anti-apoptotic effect in cerebral I/R. Our data would provide a new molecular basis for further understanding of protective effect of losartan in cerebral I/R injury and may provide benefits of using losartan in the treatment of cerebrovascular disease. Copyright © 2017 Elsevier B.V. All rights reserved.

Fractalkine is a "find-me" signal released by neurons undergoing ethanol-induced apoptosis.

PubMed

Sokolowski, Jennifer D; Chabanon-Hicks, Chloe N; Han, Claudia Z; Heffron, Daniel S; Mandell, James W

2014-01-01

Apoptotic neurons generated during normal brain development or secondary to pathologic insults are efficiently cleared from the central nervous system. Several soluble factors, including nucleotides, cytokines, and chemokines are released from injured neurons, signaling microglia to find and clear debris. One such chemokine that serves as a neuronal-microglial communication factor is fractalkine, with roles demonstrated in several models of adult neurological disorders. Lacking, however, are studies investigating roles for fractalkine in perinatal brain injury, an important clinical problem with no effective therapies. We used a well-characterized mouse model of ethanol-induced apoptosis to assess the role of fractalkine in neuronal-microglial signaling. Quantification of apoptotic debris in fractalkine-knockout (KO) and CX3CR1-KO mice following ethanol treatment revealed increased apoptotic bodies compared to wild type mice. Ethanol-induced injury led to release of soluble, extracellular fractalkine. The extracellular media harvested from apoptotic brains induces microglial migration in a fractalkine-dependent manner that is prevented by neutralization of fractalkine with a blocking antibody or by deficiency in the receptor, CX3CR1. This suggests fractalkine acts as a "find-me" signal, recruiting microglial processes toward apoptotic cells to promote their clearance. Next, we aimed to determine whether there are downstream alterations in cytokine gene expression due to fractalkine signaling. We examined mRNA expression in fractalkine-KO and CX3CR1-KO mice after alcohol-induced apoptosis and found differences in cytokine production in the brains of these KOs by 6 h after ethanol treatment. Collectively, this suggests that fractalkine acts as a "find me" signal released by apoptotic neurons, and subsequently plays a critical role in modulating both clearance and inflammatory cytokine gene expression after ethanol-induced apoptosis.

Phosphorylation of Puma modulates its apoptotic function by regulating protein stability

PubMed Central

Fricker, M; O'Prey, J; Tolkovsky, A M; Ryan, K M

2010-01-01

Puma is a potent BH3-only protein that antagonises anti-apoptotic Bcl-2 proteins, promotes Bax/Bak activation and has an essential role in multiple apoptotic models. Puma expression is normally kept very low, but can be induced by several transcription factors including p53, p73, E2F1 and FOXO3a, whereby it can induce an apoptotic response. As Puma can to bind and inactivate all anti-apoptotic members of the Bcl-2 family, its activity must be tightly controlled. We report here, for the first time, evidence that Puma is subject to post-translational control through phosphorylation. We show that Puma is phosphorylated at multiple sites, with the major site of phosphorylation being serine 10. Replacing serine 10 with alanine causes reduced Puma turnover and enhanced cell death. Interestingly, Puma turnover occurs through the proteasome, and substitution of serine 10 causes elevated Puma levels independently of macroautophagy, Bcl-2 family member binding, caspase activity and apoptotic death. We conclude, therefore, that phosphorylation of Puma at serine 10 promotes Puma turnover, represses Puma's cell death potential and promotes cell survival. Owing to the highly pro-apoptotic nature of Puma, these studies highlight an important additional regulatory step in the determination of cellular life or death. PMID:21364664

The many ways tissue phagocytes respond to dying cells

PubMed Central

Blander, J. Magarian

2017-01-01

Summary Apoptosis is an important component of normal tissue physiology, and the prompt removal of apoptotic cells is equally essential to avoid the undesirable consequences of their accumulation and disintegration. Professional phagocytes are highly specialized for engulfing apoptotic cells. The recent ability to track cells that have undergone apoptosis in situ has revealed a division of labor among the tissue resident phagocytes that sample them. Macrophages are uniquely programmed to process internalized apoptotic cell-derived fatty acids, cholesterol and nucleotides, as a reflection of their dominant role in clearing the bulk of apoptotic cells. Dendritic cells carry apoptotic cells to lymph nodes where they signal the emergence and expansion of highly suppressive regulatory CD4 T cells. A broad suppression of inflammation is executed through distinct phagocyte-specific mechanisms. A clever induction of negative regulatory nodes is notable in dendritic cells serving to simultaneously shut down multiple pathways of inflammation. Several of the genes and pathways modulated in phagocytes in response to apoptotic cells have been linked to chronic inflammatory and autoimmune diseases such as atherosclerosis, inflammatory bowel disease and systemic lupus erythematosus. Our collective understanding of old and new phagocyte functions after apoptotic cell phagocytosis demonstrates the enormity of ways to mediate immune suppression and enforce tissue homeostasis. PMID:28462530

The many ways tissue phagocytes respond to dying cells.

PubMed

Blander, J Magarian

2017-05-01

Apoptosis is an important component of normal tissue physiology, and the prompt removal of apoptotic cells is equally essential to avoid the undesirable consequences of their accumulation and disintegration. Professional phagocytes are highly specialized for engulfing apoptotic cells. The recent ability to track cells that have undergone apoptosis in situ has revealed a division of labor among the tissue resident phagocytes that sample them. Macrophages are uniquely programmed to process internalized apoptotic cell-derived fatty acids, cholesterol and nucleotides, as a reflection of their dominant role in clearing the bulk of apoptotic cells. Dendritic cells carry apoptotic cells to lymph nodes where they signal the emergence and expansion of highly suppressive regulatory CD4 T cells. A broad suppression of inflammation is executed through distinct phagocyte-specific mechanisms. A clever induction of negative regulatory nodes is notable in dendritic cells serving to simultaneously shut down multiple pathways of inflammation. Several of the genes and pathways modulated in phagocytes in response to apoptotic cells have been linked to chronic inflammatory and autoimmune diseases such as atherosclerosis, inflammatory bowel disease and systemic lupus erythematosus. Our collective understanding of old and new phagocyte functions after apoptotic cell phagocytosis demonstrates the enormity of ways to mediate immune suppression and enforce tissue homeostasis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

HIPK2 modulates p53 activity towards pro-apoptotic transcription.

PubMed

Puca, Rosa; Nardinocchi, Lavinia; Sacchi, Ada; Rechavi, Gideon; Givol, David; D'Orazi, Gabriella

2009-10-14

Activation of p53-mediated gene transcription is a critical cellular response to DNA damage and involves a phosphorylation-acetylation cascade of p53. The discovery of differences in the response to different agents raises the question whether some of the p53 oncosuppressor functions might be exerted by different posttranslational modifications. Stress-induced homeodomain-interacting protein kinase-2 (HIPK2) phosphorylates p53 at serine-46 (Ser46) for p53 apoptotic activity; p53 acetylation at different C-terminus lysines including p300-mediated lysine-382 (Lys382) is also required for full activation of p53 transcriptional activity. The purpose of the current study was to evaluate the interplay among HIPK2, p300, and p53 in p53 acetylation and apoptotic transcriptional activity in response to drug by using siRNA interference, p300 overexpression or deacetylase inhibitors, in cancer cells. Knockdown of HIPK2 inhibited both adriamycin-induced Ser46 phosphorylation and Lys382 acetylation in p53 protein; however, while combination of ADR and zinc restored Ser46 phosphorylation it did not recover Lys382 acetylation. Chromatin immunoprecipitation studies showed that HIPK2 was required in vivo for efficient p300/p53 co-recruitment onto apoptotic promoters and that both p53 modifications at Ser46 and Lys382 were necessary for p53 apoptotic transcription. Thus, p53Lys382 acetylation in HIPK2 knockdown as well as p53 apoptotic activity in response to drug could be rescued by p300 overexpression. Similar effect was obtained with the Sirt1-inhibitor nicotinamide. Interestingly trichostatin A (TSA), the inhibitor of histone deacetylase complexes (HDAC) did not have effect, suggesting that Sirt1 was the deacetylase involved in p53 deacetylation in HIPK2 knockdown. These results reveal a novel role for HIPK2 in activating p53 apoptotic transcription. Our results indicate that HIPK2 may regulate the balance between p53 acetylation and deacetylation, by stimulating on one hand co-recruitment of p300 and p53Lys382 on apoptotic promoters and on the other hand by inhibiting Sirt1 deacetylase activity. We attempted to reactivate p53 apoptotic transcriptional activity by rescuing both Ser46 and Lys382 modification in response to drug. Our data propose combination strategies for the treatment of tumors with dysfunctional p53 and/or HIPK2 that include classical chemotherapy with pharmacological or natural agents such as Sirt1-deacetylase inhibitors or zinc, respectively.

Apoptosis and Molecular Targeting Therapy in Cancer

PubMed Central

Hassan, Mohamed; Watari, Hidemichi; AbuAlmaaty, Ali; Ohba, Yusuke; Sakuragi, Noriaki

2014-01-01

Apoptosis is the programmed cell death which maintains the healthy survival/death balance in metazoan cells. Defect in apoptosis can cause cancer or autoimmunity, while enhanced apoptosis may cause degenerative diseases. The apoptotic signals contribute into safeguarding the genomic integrity while defective apoptosis may promote carcinogenesis. The apoptotic signals are complicated and they are regulated at several levels. The signals of carcinogenesis modulate the central control points of the apoptotic pathways, including inhibitor of apoptosis (IAP) proteins and FLICE-inhibitory protein (c-FLIP). The tumor cells may use some of several molecular mechanisms to suppress apoptosis and acquire resistance to apoptotic agents, for example, by the expression of antiapoptotic proteins such as Bcl-2 or by the downregulation or mutation of proapoptotic proteins such as BAX. In this review, we provide the main regulatory molecules that govern the main basic mechanisms, extrinsic and intrinsic, of apoptosis in normal cells. We discuss how carcinogenesis could be developed via defective apoptotic pathways or their convergence. We listed some molecules which could be targeted to stimulate apoptosis in different cancers. Together, we briefly discuss the development of some promising cancer treatment strategies which target apoptotic inhibitors including Bcl-2 family proteins, IAPs, and c-FLIP for apoptosis induction. PMID:25013758

Clearance of Dying Cells by Phagocytes: Mechanisms and Implications for Disease Pathogenesis.

PubMed

Fond, Aaron M; Ravichandran, Kodi S

The efficient clearance of apoptotic cells is an evolutionarily conserved process crucial for homeostasis in multicellular organisms. The clearance involves a series of steps that ultimately facilitates the recognition of the apoptotic cell by the phagocytes and the subsequent uptake and processing of the corpse. These steps include the phagocyte sensing of "find-me" signals released by the apoptotic cell, recognizing "eat-me" signals displayed on the apoptotic cell surface, and then intracellular signaling within the phagocyte to mediate phagocytic cup formation around the corpse and corpse internalization, and the processing of the ingested contents. The engulfment of apoptotic cells by phagocytes not only eliminates debris from tissues but also produces an anti-inflammatory response that suppresses local tissue inflammation. Conversely, impaired corpse clearance can result in loss of immune tolerance and the development of various inflammation-associated disorders such as autoimmunity, atherosclerosis, and airway inflammation but can also affect cancer progression. Recent studies suggest that the clearance process can also influence antitumor immune responses. In this review, we will discuss how apoptotic cells interact with their engulfing phagocytes to generate important immune responses, and how modulation of such responses can influence pathology.

A near death experience: Shigella manipulates host death machinery to silence innate immunity.

PubMed

Bronner, Denise N; O'Riordan, Mary Xd

2014-10-01

Release of mitochondrial contents often triggers inflammation and cell death, and modulating this process can be advantageous to invading pathogens. In this issue of The EMBO Journal, Andree and colleagues reveal new findings that an intracellular bacterial pathogen exploits apoptotic machinery to suppress host immune signaling, yet avoids cell death. This study emphasizes the need to expand our understanding of the roles played by pro‐apoptotic proteins in non‐death scenarios.

DRF3 as a Cholesterol Dependent Regulator of Src in Prostate Cancer

DTIC Science & Technology

2009-01-01

reported to induce non-apoptotic blebbing ( Eisenmann et al., 2007), suggesting the possibility that DRF3 may oppose blebbing. DRF3 knockdown by RNA...protein DIP, was recently shown to promote plasma membrane blebbing by acting as a Dia in- hibitor ( Eisenmann et al., 2007). Non-apoptotic membrane...43-51. Eisenmann KM, Harris ES, Kitchen SM, Holman HA, Higgs HN, Alberts AS. Dia-interacting protein modulates formin-mediated actin assembly at the

The glycan-binding protein galectin-1 controls survival of epithelial cells along the crypt-villus axis of small intestine.

PubMed

Muglia, C; Mercer, N; Toscano, M A; Schattner, M; Pozner, R; Cerliani, J P; Gobbi, R Papa; Rabinovich, G A; Docena, G H

2011-05-26

Intestinal epithelial cells serve as mechanical barriers and active components of the mucosal immune system. These cells migrate from the crypt to the tip of the villus, where different stimuli can differentially affect their survival. Here we investigated, using in vitro and in vivo strategies, the role of galectin-1 (Gal-1), an evolutionarily conserved glycan-binding protein, in modulating the survival of human and mouse enterocytes. Both Gal-1 and its specific glyco-receptors were broadly expressed in small bowel enterocytes. Exogenous Gal-1 reduced the viability of enterocytes through apoptotic mechanisms involving activation of both caspase and mitochondrial pathways. Consistent with these findings, apoptotic cells were mainly detected at the tip of the villi, following administration of Gal-1. Moreover, Gal-1-deficient (Lgals1(-/-)) mice showed longer villi compared with their wild-type counterparts in vivo. In an experimental model of starvation, fasted wild-type mice displayed reduced villi and lower intestinal weight compared with Lgals1(-/-) mutant mice, an effect reflected by changes in the frequency of enterocyte apoptosis. Of note, human small bowel enterocytes were also prone to this pro-apoptotic effect. Thus, Gal-1 is broadly expressed in mucosal tissue and influences the viability of human and mouse enterocytes, an effect which might influence the migration of these cells from the crypt, the integrity of the villus and the epithelial barrier function.

Comparative Therapeutic Effects of Minocycline Treatment and Bone Marrow Mononuclear Cell Transplantation following Striatal Stroke

PubMed Central

Souza, Celice C.; da Silva, Michelle Castro; Lopes, Rosana Telma; Cardoso, Marcelo M.; Santos, Adriano Guimarães; dos Santos, Ijair Rogério

2017-01-01

We explored the comparative effects of minocycline treatment and intrastriatal BMMC transplantation after experimental striatal stroke in adult rats. Male Wistar adult rats were divided as follows: saline-treated (N = 5), minocycline-treated (N = 5), and BMMC-transplanted (N = 5) animals. Animals received intrastriatal microinjections of 80 pmol of endothelin-1 (ET-1). Behavioral tests were performed at 1, 3, and 7 days postischemia. Animals were treated with minocycline (50 mg/kg, i.p.) or intrastriatal transplants of 106 BMMCs at 24 h postischemia. Animals were perfused at 7 days after ischemic induction. Coronal sections were stained with cresyl violet for gross histopathological analysis and immunolabeled for the identification of neuronal bodies (NeuN), activated microglia/macrophages (ED1), and apoptotic cells (active caspase-3). BMMC transplantation and minocycline reduced the number of ED1+ cells (p < 0.05, ANOVA-Tukey), but BMMC afforded better results. Both treatments afforded comparable levels of neuronal preservation compared to control (p > 0.05). BMMC transplantation induced a higher decrease in the number of apoptotic cells compared to control and minocycline treatment. Both therapeutic approaches improved functional recovery in ischemic animals. The results suggest that BMMC transplantation is more effective in modulating microglial activation and reducing apoptotic cell death than minocycline, although both treatments are equally efficacious on improving neuronal preservation. PMID:28713482

Comparative Therapeutic Effects of Minocycline Treatment and Bone Marrow Mononuclear Cell Transplantation following Striatal Stroke.

PubMed

Souza, Celice C; da Silva, Michelle Castro; Lopes, Rosana Telma; Cardoso, Marcelo M; de Souza, Lucas Lacerda; Santos, Adriano Guimarães; Dos Santos, Ijair Rogério; Franco, Edna C S; Gomes-Leal, Walace

2017-01-01

We explored the comparative effects of minocycline treatment and intrastriatal BMMC transplantation after experimental striatal stroke in adult rats. Male Wistar adult rats were divided as follows: saline-treated ( N = 5), minocycline-treated ( N = 5), and BMMC-transplanted ( N = 5) animals. Animals received intrastriatal microinjections of 80 pmol of endothelin-1 (ET-1). Behavioral tests were performed at 1, 3, and 7 days postischemia. Animals were treated with minocycline (50 mg/kg, i.p.) or intrastriatal transplants of 106 BMMCs at 24 h postischemia. Animals were perfused at 7 days after ischemic induction. Coronal sections were stained with cresyl violet for gross histopathological analysis and immunolabeled for the identification of neuronal bodies (NeuN), activated microglia/macrophages (ED1), and apoptotic cells (active caspase-3). BMMC transplantation and minocycline reduced the number of ED1+ cells ( p < 0.05, ANOVA-Tukey), but BMMC afforded better results. Both treatments afforded comparable levels of neuronal preservation compared to control ( p > 0.05). BMMC transplantation induced a higher decrease in the number of apoptotic cells compared to control and minocycline treatment. Both therapeutic approaches improved functional recovery in ischemic animals. The results suggest that BMMC transplantation is more effective in modulating microglial activation and reducing apoptotic cell death than minocycline, although both treatments are equally efficacious on improving neuronal preservation.

Neutral sphingomyelinase 2 modulates cytotoxic effects of protopanaxadiol on different human cancer cells

PubMed Central

2013-01-01

Background Some of ginsenosides, root extracts from Panax ginseng, exert cytotoxicity against cancer cells through disruption of membrane subdomains called lipid rafts. Protopanaxadiol (PPD) exhibits the highest cytotoxic effect among 8 ginsenosides which we evaluated for anti-cancer activity. We investigated if PPD disrupts lipid rafts in its cytotoxic effects and also the possible mechanisms. Methods Eight ginsenosides were evaluated using different cancer cells and cell viability assays. The potent ginsenoside, PPD was investigated for its roles in lipid raft disruption and downstream pathways to apoptosis of cancer cells. Anti-cancer effects of PPD was also investigated in vivo using mouse xenograft model. Results PPD consistently exerts its potent cytotoxicity in 2 cell survival assays using 5 different cancer cell lines. PPD disrupts lipid rafts in different ways from methyl-β-cyclodextrin (MβCD) depleting cholesterol out of the subdomains, since lipid raft proteins were differentially modulated by the saponin. During disruption of lipid rafts, PPD activated neutral sphingomyelinase 2 (nSMase 2) hydrolyzing membrane sphingomyelins into pro-apoptotic intracellular ceramides. Furthermore, PPD demonstrated its anti-cancer activities against K562 tumor cells in mouse xenograft model, confirming its potential as an adjunct or chemotherapeutic agent by itself in vivo. Conclusions This study demonstrates that neutral sphingomyelinase 2 is responsible for the cytotoxicity of PPD through production of apoptotic ceramides from membrane sphingomyelins. Thus neutral sphingomyelinase 2 and its relevant mechanisms may potentially be employed in cancer chemotherapies. PMID:23889969

Use of Autoantigen-Loaded Phosphatidylserine-Liposomes to Arrest Autoimmunity in Type 1 Diabetes

PubMed Central

Pujol-Autonell, Irma; Serracant-Prat, Arnau; Cano-Sarabia, Mary; Ampudia, Rosa M.; Rodriguez-Fernandez, Silvia; Sanchez, Alex; Izquierdo, Cristina; Stratmann, Thomas; Puig-Domingo, Manuel; Maspoch, Daniel; Verdaguer, Joan; Vives-Pi, Marta

2015-01-01

Introduction The development of new therapies to induce self-tolerance has been an important medical health challenge in type 1 diabetes. An ideal immunotherapy should inhibit the autoimmune attack, avoid systemic side effects and allow β-cell regeneration. Based on the immunomodulatory effects of apoptosis, we hypothesized that apoptotic mimicry can help to restore tolerance lost in autoimmune diabetes. Objective To generate a synthetic antigen-specific immunotherapy based on apoptosis features to specifically reestablish tolerance to β-cells in type 1 diabetes. Methods A central event on the surface of apoptotic cells is the exposure of phosphatidylserine, which provides the main signal for efferocytosis. Therefore, phosphatidylserine-liposomes loaded with insulin peptides were generated to simulate apoptotic cells recognition by antigen presenting cells. The effect of antigen-specific phosphatidylserine-liposomes in the reestablishment of peripheral tolerance was assessed in NOD mice, the spontaneous model of autoimmune diabetes. MHC class II-peptide tetramers were used to analyze the T cell specific response after treatment with phosphatidylserine-liposomes loaded with peptides. Results We have shown that phosphatidylserine-liposomes loaded with insulin peptides induce tolerogenic dendritic cells and impair autoreactive T cell proliferation. When administered to NOD mice, liposome signal was detected in the pancreas and draining lymph nodes. This immunotherapy arrests the autoimmune aggression, reduces the severity of insulitis and prevents type 1 diabetes by apoptotic mimicry. MHC class II tetramer analysis showed that peptide-loaded phosphatidylserine-liposomes expand antigen-specific CD4+ T cells in vivo. The administration of phosphatidylserine-free liposomes emphasizes the importance of phosphatidylserine in the modulation of antigen-specific CD4+ T cell expansion. Conclusions We conclude that this innovative immunotherapy based on the use of liposomes constitutes a promising strategy for autoimmune diseases. PMID:26039878

Use of autoantigen-loaded phosphatidylserine-liposomes to arrest autoimmunity in type 1 diabetes.

PubMed

Pujol-Autonell, Irma; Serracant-Prat, Arnau; Cano-Sarabia, Mary; Ampudia, Rosa M; Rodriguez-Fernandez, Silvia; Sanchez, Alex; Izquierdo, Cristina; Stratmann, Thomas; Puig-Domingo, Manuel; Maspoch, Daniel; Verdaguer, Joan; Vives-Pi, Marta

2015-01-01

The development of new therapies to induce self-tolerance has been an important medical health challenge in type 1 diabetes. An ideal immunotherapy should inhibit the autoimmune attack, avoid systemic side effects and allow β-cell regeneration. Based on the immunomodulatory effects of apoptosis, we hypothesized that apoptotic mimicry can help to restore tolerance lost in autoimmune diabetes. To generate a synthetic antigen-specific immunotherapy based on apoptosis features to specifically reestablish tolerance to β-cells in type 1 diabetes. A central event on the surface of apoptotic cells is the exposure of phosphatidylserine, which provides the main signal for efferocytosis. Therefore, phosphatidylserine-liposomes loaded with insulin peptides were generated to simulate apoptotic cells recognition by antigen presenting cells. The effect of antigen-specific phosphatidylserine-liposomes in the reestablishment of peripheral tolerance was assessed in NOD mice, the spontaneous model of autoimmune diabetes. MHC class II-peptide tetramers were used to analyze the T cell specific response after treatment with phosphatidylserine-liposomes loaded with peptides. We have shown that phosphatidylserine-liposomes loaded with insulin peptides induce tolerogenic dendritic cells and impair autoreactive T cell proliferation. When administered to NOD mice, liposome signal was detected in the pancreas and draining lymph nodes. This immunotherapy arrests the autoimmune aggression, reduces the severity of insulitis and prevents type 1 diabetes by apoptotic mimicry. MHC class II tetramer analysis showed that peptide-loaded phosphatidylserine-liposomes expand antigen-specific CD4+ T cells in vivo. The administration of phosphatidylserine-free liposomes emphasizes the importance of phosphatidylserine in the modulation of antigen-specific CD4+ T cell expansion. We conclude that this innovative immunotherapy based on the use of liposomes constitutes a promising strategy for autoimmune diseases.

Enhancement of UVB radiation-mediated apoptosis by knockdown of cytosolic NADP+-dependent isocitrate dehydrogenase in HaCaT cells

PubMed Central

Lee, Su Jeong; Park, Jeen-Woo

2014-01-01

Ultraviolet B (UVB) radiation induces the production of reactive oxygen species (ROS) that promote apoptotic cell death. We showed that cytosolic NADP+-dependent isocitrate dehydrogenase (IDPc) plays an essential role in the control of cellular redox balance and defense against oxidative damage, by supplying NADPH for antioxidant systems. In this study, we demonstrated that knockdown of IDPc expression by RNA interference enhances UVB-induced apoptosis of immortalized human HaCaT keratinocytes. This effect manifested as DNA fragmentation, changes in cellular redox status, mitochondrial dysfunction, and modulation of apoptotic marker expression. Based on our findings, we suggest that attenuation of IDPc expression may protect skin from UVB-mediated damage, by inducing the apoptosis of UV-damaged cells. [BMB Reports 2014; 47(4): 209-214] PMID:24286310

Oncogenic Properties of Apoptotic Tumor Cells in Aggressive B Cell Lymphoma

PubMed Central

Ford, Catriona A.; Petrova, Sofia; Pound, John D.; Voss, Jorine J.L.P.; Melville, Lynsey; Paterson, Margaret; Farnworth, Sarah L.; Gallimore, Awen M.; Cuff, Simone; Wheadon, Helen; Dobbin, Edwina; Ogden, Carol Anne; Dumitriu, Ingrid E.; Dunbar, Donald R.; Murray, Paul G.; Ruckerl, Dominik; Allen, Judith E.; Hume, David A.; van Rooijen, Nico; Goodlad, John R.; Freeman, Tom C.; Gregory, Christopher D.

2015-01-01

Summary Background Cells undergoing apoptosis are known to modulate their tissue microenvironments. By acting on phagocytes, notably macrophages, apoptotic cells inhibit immunological and inflammatory responses and promote trophic signaling pathways. Paradoxically, because of their potential to cause death of tumor cells and thereby militate against malignant disease progression, both apoptosis and tumor-associated macrophages (TAMs) are often associated with poor prognosis in cancer. We hypothesized that, in progression of malignant disease, constitutive loss of a fraction of the tumor cell population through apoptosis could yield tumor-promoting effects. Results Here, we demonstrate that apoptotic tumor cells promote coordinated tumor growth, angiogenesis, and accumulation of TAMs in aggressive B cell lymphomas. Through unbiased “in situ transcriptomics” analysis—gene expression profiling of laser-captured TAMs to establish their activation signature in situ—we show that these cells are activated to signal via multiple tumor-promoting reparatory, trophic, angiogenic, tissue remodeling, and anti-inflammatory pathways. Our results also suggest that apoptotic lymphoma cells help drive this signature. Furthermore, we demonstrate that, upon induction of apoptosis, lymphoma cells not only activate expression of the tumor-promoting matrix metalloproteinases MMP2 and MMP12 in macrophages but also express and process these MMPs directly. Finally, using a model of malignant melanoma, we show that the oncogenic potential of apoptotic tumor cells extends beyond lymphoma. Conclusions In addition to its profound tumor-suppressive role, apoptosis can potentiate cancer progression. These results have important implications for understanding the fundamental biology of cell death, its roles in malignant disease, and the broader consequences of apoptosis-inducing anti-cancer therapy. PMID:25702581

Modulation of the AMPK/Sirt1 axis during neuronal infection by herpes simplex virus type 1.

PubMed

Martin, Carolina; Leyton, Luis; Arancibia, Yennyfer; Cuevas, Alexei; Zambrano, Angara; Concha, Margarita I; Otth, Carola

2014-01-01

Currently, it is unclear whether a neuron that undergoes viral reactivation and produces infectious particles survives and resumes latency or is killed, which is intriguing even if still unanswered. Previous reports have shown that herpes simplex virus type 1 (HSV-1) inhibits apoptosis during early infection, but is pro-apoptotic during productive infection. Taking in consideration that the stress sensors AMPK and Sirt1 are involved in neuronal survival and neuroprotection, we hypothesized that HSV-1 could activate the AMPK/Sirt1 axis as a strategy to establish latency through inhibition of apoptosis and restoration of the energy status. These effects could be accomplished through deacetylation of pro-apoptotic protein p53 and regulation of the master regulator of mitochondrial biogenesis and function PGC-1α and its target gene TFAM. Accordingly, we evaluated the AMPK/Sirt1 axis and its targets p53, PGC-1α, and acetyl CoA carboxylase in mice neuronal cultures infected with HSV-1 by western blot, RT-qPCR, and immunofluorescence analyses. Herein, we show that HSV-1 differentially modulates the AMPK/Sirt1 axis during the course of infection. In fact, during early infection (2 hpi) activated AMPK (p-AMPK) was down-regulated, but thereafter recovered gradually. In contrast, the levels of acetylated-p53 increased during the first hours post infection, but afterwards were reduced in parallel with the activation of Sirt1. However, acetylated-p53 peaked again at 18 hpi during productive infection, suggesting an activation of apoptosis. Strikingly, acetylated-p53, Sirt1, and p-AMPK apparently translocate from the nucleus to the cytoplasm after 4 hpi, where they accumulate in discrete foci in the perinuclear region. These results suggest that HSV-1 modulates the AMPK/Sirt1 axis differentially during the course of infection interfering with pro-apoptotic signaling and regulating mitochondrial biogenesis.

Garlic-Derived S-Allylmercaptocysteine Ameliorates Nonalcoholic Fatty Liver Disease in a Rat Model through Inhibition of Apoptosis and Enhancing Autophagy

PubMed Central

Fung, Man-Lung; Liong, Emily C.; Chang, Raymond Chuen Chung; Ching, Yick-Pang; Tipoe, George L.

2013-01-01

Our previous study demonstrated that administration of garlic-derived antioxidant S-allylmercaptocysteine (SAMC) ameliorated hepatic injury in a nonalcoholic fatty liver disease (NAFLD) rat model. Our present study aimed to investigate the mechanism of SAMC on NAFLD-induced hepatic apoptosis and autophagy. Adult female rats were fed with a high-fat diet for 8 weeks to develop NAFLD with or without intraperitoneal injection of 200 mg/kg SAMC for three times per week. During NAFLD development, increased apoptotic cells and caspase-3 activation were observed in the liver. Increased apoptosis was modulated through both intrinsic and extrinsic apoptotic pathways. NAFLD treatment also enhanced the expression of key autophagic markers in the liver with reduced activity of LKB1/AMPK and PI3K/Akt pathways. Increased expression of proapoptotic regulator p53 and decreased activity of antiautophagic regulator mTOR were also observed. Administration of SAMC reduced the number of apoptotic cells through downregulation of both intrinsic and extrinsic apoptotic mechanisms. SAMC also counteracted the effects of NAFLD on LKB1/AMPK and PI3K/Akt pathways. Treatment with SAMC further enhanced hepatic autophagy by regulating autophagic markers and mTOR activity. In conclusion, administration of SAMC during NAFLD development in rats protects the liver from chronic injury by reducing apoptosis and enhancing autophagy. PMID:23861709

Role of Zucchini and Its Distinctive Components in the Modulation of Degenerative Processes: Genotoxicity, Anti-Genotoxicity, Cytotoxicity and Apoptotic Effects

PubMed Central

Martínez-Valdivieso, Damián; Font, Rafael; Fernández-Bedmar, Zahira; Merinas-Amo, Tania; Gómez, Pedro; Alonso-Moraga, Ángeles

2017-01-01

Zucchini (Cucurbita pepo subsp. pepo) is a seasonal vegetable with high nutritional and medical values. Many useful properties of this fruit are attributed to bioactive compounds. Zucchini fruits (“Yellow” and “Light Green” varieties) and four distinctive components (lutein, β-carotene, zeaxanthin and dehydroascorbic acid) were selected. Firstly, the lutein, β-carotene, zeaxanthin and dehydroascorbic acid contents were determined in these fruits. Then, in order to evaluate the safety and suitability of their use, different assays were carried out: (i) genotoxicity and anti-genotoxicity tests to determine the safety and DNA-protection against hydrogen peroxide; (ii) cytotoxicity; and (iii) DNA fragmentation and Annexin V/PI (Propidium Iodide) assays to evaluate the pro-apoptotic effect. Results showed that: (i) all the substances were non-genotoxic; (ii) all the substances were anti-genotoxic except the highest concentration of lutein; (iii) “Yellow” zucchini epicarp and mesocarp exhibited the highest cytotoxic activity (IC50 > 0.1 mg/mL and 0.2 mg/mL, respectively); and (iv) “Light Green” zucchini skin induced internucleosomal DNA fragmentation, β-carotene being the possible molecule responsible for its pro-apoptotic activity. To sum up, zucchini fruit could play a positive role in human health and nutrition due to this fruit and its components were safe, able to inhibit significantly the H2O2-induced damage and exhibit anti-proliferative and pro-apoptotic activities toward HL60 (human promyelocytic leukemia cells) tumor cells. The information generated from this research should be considered when selecting potential accessions for breeding program purposes. PMID:28708122

Role of Zucchini and Its Distinctive Components in the Modulation of Degenerative Processes: Genotoxicity, Anti-Genotoxicity, Cytotoxicity and Apoptotic Effects.

PubMed

Martínez-Valdivieso, Damián; Font, Rafael; Fernández-Bedmar, Zahira; Merinas-Amo, Tania; Gómez, Pedro; Alonso-Moraga, Ángeles; Del Río-Celestino, Mercedes

2017-07-14

Zucchini ( Cucurbita pepo subsp. pepo ) is a seasonal vegetable with high nutritional and medical values. Many useful properties of this fruit are attributed to bioactive compounds. Zucchini fruits ("Yellow" and "Light Green" varieties) and four distinctive components (lutein, β-carotene, zeaxanthin and dehydroascorbic acid) were selected. Firstly, the lutein, β-carotene, zeaxanthin and dehydroascorbic acid contents were determined in these fruits. Then, in order to evaluate the safety and suitability of their use, different assays were carried out: (i) genotoxicity and anti-genotoxicity tests to determine the safety and DNA-protection against hydrogen peroxide; (ii) cytotoxicity; and (iii) DNA fragmentation and Annexin V/PI (Propidium Iodide) assays to evaluate the pro-apoptotic effect. Results showed that: (i) all the substances were non-genotoxic; (ii) all the substances were anti-genotoxic except the highest concentration of lutein; (iii) "Yellow" zucchini epicarp and mesocarp exhibited the highest cytotoxic activity (IC 50 > 0.1 mg/mL and 0.2 mg/mL, respectively); and (iv) "Light Green" zucchini skin induced internucleosomal DNA fragmentation, β-carotene being the possible molecule responsible for its pro-apoptotic activity. To sum up, zucchini fruit could play a positive role in human health and nutrition due to this fruit and its components were safe, able to inhibit significantly the H₂O₂-induced damage and exhibit anti-proliferative and pro-apoptotic activities toward HL60 (human promyelocytic leukemia cells) tumor cells. The information generated from this research should be considered when selecting potential accessions for breeding program purposes.

Differences in the rate of oestrogen-induced apoptosis in breast cancer by oestradiol and the triphenylethylene bisphenol

PubMed Central

Obiorah, I E; Jordan, V C

2014-01-01

Background and Purpose Triphenylethylene (TPE)-like compounds were the first agents to be used in the treatment of metastatic breast cancer in postmenopausal women. Although structurally related to the anti-oestrogen, 4-hydroxytamoxifen, TPEs possess oestrogenic properties in fully oestrogenized breast cancer cells but do not induce apoptosis with short-term treatment in long-term oestrogen-deprived breast cancer cells. This study determined the differential effects of bisphenol, a TPE, on growth and apoptosis based on the modulation of the shape of the ligand–oestrogen receptor complex. Experimental Approach Apoptotic flow cytometric studies were used to evaluate apoptosis over time. Proliferation of the breast cancer cells was assessed using DNA quantification and cell cycle analysis. Real-time PCR was performed to quantify mRNA levels of apoptotic genes. Regulation of cell cycle and apoptotic genes was determined using PCR-based arrays. Key Results Bisphenol induced an up-regulation of cell cycle genes similar to those induced by 17β oestradiol (E2). Unlike the changes induced by E2 that occur after 24 h, the apoptosis evoked by bisphenol occurred after 4 days, with quantifiable apoptotic changes noted at 6 days. A prolonged up-regulation of endoplasmic reticulum stress and inflammatory stress response genes was observed with subsequent activation of apoptosis-related genes in the second week of treatment with bisphenol. Conclusions and Implications The bisphenol: ERα complex induces delayed biological effects on the growth and apoptosis of breast cancer cells. Both the shape of the complex and the duration of treatment control the initiation of apoptosis. PMID:24819221

Resveratrol suppresses growth of cancer stem-like cells by inhibiting fatty acid synthase.

PubMed

Pandey, Puspa R; Okuda, Hiroshi; Watabe, Misako; Pai, Sudha K; Liu, Wen; Kobayashi, Aya; Xing, Fei; Fukuda, Koji; Hirota, Shigeru; Sugai, Tamotsu; Wakabayashi, Go; Koeda, Keisuke; Kashiwaba, Masahiro; Suzuki, Kazuyuki; Chiba, Toshimi; Endo, Masaki; Fujioka, Tomoaki; Tanji, Susumu; Mo, Yin-Yuan; Cao, Deliang; Wilber, Andrew C; Watabe, Kounosuke

2011-11-01

Resveratrol is a natural polyphenolic compound and has been shown to exhibit cardio-protective as well as anti-neoplastic effects on various types of cancers. However, the exact mechanism of its anti-tumor effect is not clearly defined. Resveratrol has been shown to have strong hypolipidemic effect on normal adipocytes and as hyper-lipogenesis is a hallmark of cancer cell physiology, the effect of resveratrol on lipid synthesis in cancer stem-like cells (CD24(-)/CD44(+)/ESA(+)) that were isolated from both ER+ and ER- breast cancer cell lines was examined. The authors found that resveratrol significantly reduced the cell viability and mammosphere formation followed by inducing apoptosis in cancer stem-like cells. This inhibitory effect of resveratrol is accompanied by a significant reduction in lipid synthesis which is caused by the down-regulation of the fatty acid synthase (FAS) gene followed by up-regulation of pro-apoptotic genes, DAPK2 and BNIP3. The activation of apoptotic pathway in the cancer stem-like cells was suppressed by TOFA and by Fumonisin B1, suggesting that resveratrol-induced apoptosis is indeed through the modulation of FAS-mediated cell survival signaling. Importantly, resveratrol was able to significantly suppress the growth of cancer stem-like cells in an animal model of xenograft without showing apparental toxicity. Taken together, the results of this study indicate that resveratrol is capable of inducing apoptosis in the cancer stem-like cells through suppression of lipogenesis by modulating FAS expression, which highlights a novel mechanism of anti-tumor effect of resveratrol.

Resveratrol suppresses growth of cancer stem-like cells by inhibiting fatty acid synthase

PubMed Central

Pandey, Puspa R.; Okuda, Hiroshi; Watabe, Misako; Pai, Sudha K.; Liu, Wen; Kobayashi, Aya; Xing, Fei; Fukuda, Koji; Hirota, Shigeru; Sugai, Tamotsu; Wakabayashi, Go; Koeda, Keisuke; Kashiwaba, Masahiro; Suzuki, Kazuyuki; Chiba, Toshimi; Endo, Masaki; Fujioka, Tomoaki; Tanji, Susumu; Mo, Yin-Yuan; Cao, Deliang; Wilber, Andrew C.; Watabe, Kounosuke

2012-01-01

Resveratrol is a natural polyphenolic compound and has been shown to exhibit cardio-protective as well as anti-neoplastic effects on various types of cancers. However, the exact mechanism of its anti-tumor effect is not clearly defined. Resveratrol has been shown to have strong hypolipidemic effect on normal adipocytes and as hyper-lipogenesis is a hallmark of cancer cell physiology, we examined the effect of resveratrol on lipid synthesis in cancer stem-like cells (CD24−/CD44+/ESA+) that were isolated from both ER+ and ER− breast cancer cell lines. We found that resveratrol significantly reduced the cell viability and mammosphere formation followed by inducing apoptosis in cancer stem-like cells. This inhibitory effect of resveratrol is accompanied by a significant reduction in lipid synthesis which is caused by the down-regulation of the fatty acid synthase (FAS) gene followed by up-regulation of pro-apoptotic genes, DAPK2 and BNIP3. The activation of apoptotic pathway in the cancer stem-like cells was suppressed by TOFA and by Fumonisin B1, suggesting that resveratrol-induced apoptosis is indeed through the modulation of FAS-mediated cell survival signaling. Importantly, resveratrol was able to significantly suppress the growth of cancer stem-like cells in an animal model of xenograft without showing apparental toxicity. Taken together, our results indicate that resveratrol is capable of inducing apoptosis in the cancer stem-like cells through suppression of lipogenesis by modulating FAS expression, which highlights a novel mechanism of anti-tumor effect of resveratrol. PMID:21188630

Sulphoraphane, a naturally occurring isothiocyanate induces apoptosis in breast cancer cells by targeting heat shock proteins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarkar, Ruma; Mukherjee, Sutapa; Biswas, Jaydip

Highlights: Black-Right-Pointing-Pointer HSPs (27, 70 and 90) and HSF1 are overexpressed in MCF-7 and MDA-MB-231 cells. Black-Right-Pointing-Pointer Sulphoraphane, a natural isothiocyanate inhibited HSPs and HSF1 expressions. Black-Right-Pointing-Pointer Inhibition of HSPs and HSF1 lead to regulation of apoptotic proteins. Black-Right-Pointing-Pointer Alteration of apoptotic proteins activate of caspases particularly caspase 3 and 9 leading to induction of apoptosis. Black-Right-Pointing-Pointer Alteration of apoptotic proteins induce caspases leading to induction of apoptosis. -- Abstract: Heat shock proteins (HSPs) are involved in protein folding, aggregation, transport and/or stabilization by acting as a molecular chaperone, leading to inhibition of apoptosis by both caspase dependent and/or independentmore » pathways. HSPs are overexpressed in a wide range of human cancers and are implicated in tumor cell proliferation, differentiation, invasion and metastasis. HSPs particularly 27, 70, 90 and the transcription factor heat shock factor1 (HSF1) play key roles in the etiology of breast cancer and can be considered as potential therapeutic target. The present study was designed to investigate the role of sulphoraphane, a natural isothiocyanate on HSPs (27, 70, 90) and HSF1 in two different breast cancer cell lines MCF-7 and MDA-MB-231 cells expressing wild type and mutated p53 respectively, vis-a-vis in normal breast epithelial cell line MCF-12F. It was furthermore investigated whether modulation of HSPs and HSF1 could induce apoptosis in these cells by altering the expressions of p53, p21 and some apoptotic proteins like Bcl-2, Bax, Bid, Bad, Apaf-1 and AIF. Sulphoraphane was found to down-regulate the expressions of HSP70, 90 and HSF1, though the effect on HSP27 was not pronounced. Consequences of HSP inhibition was upregulation of p21 irrespective of p53 status. Bax, Bad, Apaf-1, AIF were upregulated followed by down-regulation of Bcl-2 and this effect was prominent in MCF-7 than in MDA-MB-231. However, very little change in the expression of Bid was observed. Alteration in Bcl-2 Bax ratio resulted in the release of cytochrome c from mitochondria and activation of caspases 3 and 9 which are in agreement with apoptotic index values. Sulphoraphane therefore can be regarded as a potent inducer of apoptosis due to HSP modulation in breast cancer cells.« less

Amelioration of nandrolone decanoate-induced testicular and sperm toxicity in rats by taurine: Effects on steroidogenesis, redox and inflammatory cascades, and intrinsic apoptotic pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahmed, Maha A.E., E-mail: mahapharm@yahoo.com

The wide abuse of the anabolic steroid nandrolone decanoate by athletes and adolescents for enhancement of sporting performance and physical appearance may be associated with testicular toxicity and infertility. On the other hand, taurine; a free β-amino acid with remarkable antioxidant activity, is used in taurine-enriched beverages to boost the muscular power of athletes. Therefore, the purpose of this study was to investigate the mechanisms of the possible protective effects of taurine on nandrolone decanoate-induced testicular and sperm toxicity in rats. To achieve this aim, male Wistar rats were randomly distributed into four groups and administered either vehicle, nandrolone decanoatemore » (10 mg/kg/week, I.M.), taurine (100 mg/kg/day, p.o.) or combination of taurine and nandrolone decanoate, for 8 successive weeks. Results of the present study showed that taurine reversed nandrolone decanoate-induced perturbations in sperm characteristics, normalized serum testosterone level, and restored the activities of the key steroidogenic enzymes; 3β-HSD, and 17β-HSD. Moreover, taurine prevented nandrolone decanoate-induced testicular toxicity and DNA damage by virtue of its antioxidant, anti-inflammatory, and anti-apoptotic effects. This was evidenced by taurine-induced modulation of testicular LDH-x activity, redox markers (MDA, NO, GSH contents, and SOD activity), inflammatory indices (TNF-α, ICAM-1 levels, and MMP-9 gene expression), intrinsic apoptotic pathway (cytochrome c gene expression and caspase-3 content), and oxidative DNA damage markers (8-OHdG level and comet assay). In conclusion, at the biochemical and histological levels, taurine attenuated nandrolone decanoate-induced poor sperm quality and testicular toxicity in rats. - Highlights: • Nandrolone decanoate (ND) disrupts sperm profile and steroidogenesis in rats. • ND upregulates gene expression of inflammatory and apoptotic markers. • Taurine normalizes sperm profile and serum testosterone level in ND-treated rats. • Taurine prevents ND-induced testicular toxicity and DNA damage. • Taurine shows antioxidant, anti-inflammatory, and anti-apoptotic effects.« less

HSP27 Inhibits Homocysteine-Induced Endothelial Apoptosis by Modulation of ROS Production and Mitochondrial Caspase-Dependent Apoptotic Pathway.

PubMed

Tian, Xin; Zhao, Lei; Song, Xianjing; Yan, Youyou; Liu, Ning; Li, Tianyi; Yan, Bingdi; Liu, Bin

2016-01-01

Objectives. Elevated plasma homocysteine (Hcy) could lead to endothelial dysfunction and is viewed as an independent risk factor for atherosclerosis. Heat shock protein 27 (HSP27), a small heat shock protein, is reported to exert protective effect against atherosclerosis. This study aims to investigate the protective effect of HSP27 against Hcy-induced endothelial cell apoptosis in human umbilical vein endothelial cells (HUVECs) and to determine the underlying mechanisms. Methods. Apoptosis, reactive oxygen species (ROS), and mitochondrial membrane potential (MMP) of normal or HSP27-overexpressing HUVECs in the presence of Hcy were analyzed by flow cytometry. The mRNA and protein expression levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Results. We found that Hcy could induce cell apoptosis with corresponding decrease of nitric oxide (NO) level, increase of endothelin-1 (ET-1), intracellular adhesion molecule-1 (ICAM-1), vascular cellular adhesion molecule-1 (VCAM-1), and monocyte chemoattractant protein-1 (MCP-1) levels, elevation of ROS, and dissipation of MMP. In addition, HSP27 could protect the cell against Hcy-induced apoptosis and inhibit the effect of Hcy on HUVECs. Furthermore, HSP27 could increase the ratio of Bcl-2/Bax and inhibit caspase-3 activity. Conclusions. Therefore, we concluded that HSP27 played a protective role against Hcy-induced endothelial apoptosis through modulation of ROS production and the mitochondrial caspase-dependent apoptotic pathway.

Modulation of curcumin-induced Akt phosphorylation and apoptosis by PI3K inhibitor in MCF-7 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kizhakkayil, Jaleel; Thayyullathil, Faisal; Chathoth, Shahanas

2010-04-09

Curcumin has been shown to induce apoptosis in various malignant cancer cell lines. One mechanism of curcumin-induced apoptosis is through the PI3K/Akt signaling pathway. Akt, also known as protein kinase B (PKB), is a member of the family of phosphatidylinositol 3-OH-kinase regulated Ser/Thr kinases. The active Akt regulates cell survival and proliferation; and inhibits apoptosis. In this study we found that curcumin induces apoptotic cell death in MCF-7 cells, as assessed by MTT assay, DNA ladder formation, PARP cleavage, p53 and Bax induction. At apoptotic inducing concentration, curcumin induces a dramatic Akt phosphorylation, accompanied by an increased phosphorylation of glycogenmore » synthase kinase 3{beta} (GSK3{beta}), which has been considered to be a pro-growth signaling molecule. Combining curcumin with PI3K inhibitor, LY290042, synergizes the apoptotic effect of curcumin. The inhibitor LY290042 was capable of attenuating curcumin-induced Akt phosphorylation and activation of GSK3{beta}. All together, our data suggest that blocking the PI3K/Akt survival pathway sensitizes the curcumin-induced apoptosis in MCF-7 cells.« less

Apoptotic cell-mediated suppression of streptococcal cell wall-induced arthritis is associated with alteration of macrophage function and local regulatory T-cell increase: a potential cell-based therapy?

PubMed Central

Perruche, Sylvain; Saas, Philippe; Chen, Wanjun

2009-01-01

Introduction Experimental streptococcal cell wall (SCW)-induced arthritis is characterized by two successive phases of the disease. The acute phase occurs early and is associated with an inflammatory process and neutrophil infiltration into the synovium. The second chronic phase is related to effector T-cell activation and the dysregulation of macrophage function. Creation of an immunomodulatory environment has been attributed to apoptotic cells themselves, apoptotic cell uptake by phagocytes as well as a less sensibility of phagocytes capturing apoptotic bodies to activation. Therefore we evaluated the potential of apoptotic cell injection to influence the course of inflammation in SCW-induced arthritis in rats. Methods Rat apoptotic thymocytes were injected intraperitoneally (2 × 108) in addition to an arthritogenic dose of systemic SCW in LEW female rats. Control rats received SCW immunization and PBS. Rats were then followed for arthritis occurrence and circulating cytokine detection. At sacrifice, regulatory T cells (Tregs) and macrophages were analyzed. Results Apoptotic cell injection profoundly suppressed joint swelling and destruction typically observed during the acute and chronic phases of SCW-induced arthritis. Synovial inflammatory cell infiltration and bone destruction were also markedly suppressed. Ex vivo experiments revealed reduced levels of TNF in cultures of macrophages from rats challenged with SCW in the presence of apoptotic thymocytes as well as reduced macrophage response to lipopolysaccharide. Moreover, apoptotic cell injection induced higher Foxp3+ Tregs in the lymphoid organs, especially in the draining lymph nodes. Conclusions Our data indicate that apoptotic cells modulate macrophage function and result in Treg generation/increase. This may be involved in inhibition of inflammation and amelioration of arthritis. This highlights and confirms previous studies showing that in vivo generation of Tregs using apoptotic cell injection may be a useful tool to prevent and treat inflammatory autoimmune responses. PMID:19570235

Identification of a Novel Recycling Sequence in the C-tail of FPR2/ALX Receptor

PubMed Central

Thompson, Dawn; McArthur, Simon; Hislop, James N.; Flower, Roderick J.; Perretti, Mauro

2014-01-01

Formyl-peptide receptor type 2 (FPR2; also called ALX because it is the receptor for lipoxin A4) sustains a variety of biological responses relevant to the development and control of inflammation, yet the cellular regulation of this G-protein-coupled receptor remains unexplored. Here we report that, in response to peptide agonist activation, FPR2/ALX undergoes β-arrestin-mediated endocytosis followed by rapid recycling to the plasma membrane. We identify a transplantable recycling sequence that is both necessary and sufficient for efficient receptor recycling. Furthermore, removal of this C-terminal recycling sequence alters the endocytic fate of FPR2/ALX and evokes pro-apoptotic effects in response to agonist activation. This study demonstrates the importance of endocytic recycling in the anti-apoptotic properties of FPR2/ALX and identifies the molecular determinant required for modulation of this process fundamental for the control of inflammation. PMID:25326384

Physalin A exerts anti-tumor activity in non-small cell lung cancer cell lines by suppressing JAK/STAT3 signaling

PubMed Central

Loo, Jacky F.C.; Xia, Dajin; Gao, Sizhi P.; Ma, Zhongjun; Chen, Zhe

2016-01-01

The signal transducers and activators of transcription 3 (STAT3) signaling pathway plays critical roles in the pathogenesis and progression of various human cancers, including non-small cell lung cancer (NSCLC). In this study, we aimed to evaluate the therapeutic potential of physalin A, a bioactive withanolide derived from Physalis alkekengi var. francheti used in traditional Chinese medicine, was evaluated in human NSCLC cells. Its and determined whether it effect oninhibited both constitutive and induced STAT3 activity, through repressing the phosphorylation levels of JAK2 and JAK3, resulting in anti-proliferation and pro-apoptotic effects on NSCLC cells was also determined, and. theThe antitumor effects of physalin A were also validated usingin an in vivo mouse xenograft models of NSCLC cells. Physalin A had anti-proliferative and pro-apoptotic effects in NSCLC cells with constitutively activated STAT3; it also suppressed both constitutive and induced STAT3 activity by modulating the phosphorylation of JAK2 and JAK3. Furthermore, physalin A abrogated the nuclear translocation and transcriptional activity of STAT3, thereby decreasing the expression levels of STAT3, its target genes, such as Bcl-2 and XIAP. Knockdown of STAT3 expression by small interfering RNA (siRNA) significantly enhanced the pro-apoptotic effects of physalin A in NSCLC cells. Moreover, physalin A significantly suppressed tumor xenograft growth. Thus, as an inhibitor of JAK2/3-STAT3 signaling, physalin A, has potent anti-tumor activities, which may facilitate the development of a therapeutic strategy for treating NSCLC. PMID:26843613

Catalase-Modulated Heterogeneous Fenton Reaction for Selective Cancer Cell Eradication: SnFe2O4 Nanocrystals as an Effective Reagent for Treating Lung Cancer Cells.

PubMed

Lee, Kuan-Ting; Lu, Yu-Jen; Mi, Fwu-Long; Burnouf, Thierry; Wei, Yi-Ting; Chiu, Shao-Chieh; Chuang, Er-Yuan; Lu, Shih-Yuan

2017-01-18

Heterogeneous Fenton reactions have been proven to be an effective and promising selective cancer cell treatment method. The key working mechanism for this method to achieve the critical therapeutic selectivity however remains unclear. In this study, we proposed and demonstrated for the first time the critical role played by catalase in realizing the therapeutic selectivity for the heterogeneous Fenton reaction-driven cancer cell treatment. The heterogeneous Fenton reaction, with the lattice ferric ions of the solid catalyst capable of converting H 2 O 2 to highly reactive hydroxyl radicals, can effectively eradicate cancer cells. In this study, SnFe 2 O 4 nanocrystals, a recently discovered outstanding heterogeneous Fenton catalyst, were applied for selective killing of lung cancer cells. The SnFe 2 O 4 nanocrystals, internalized into the cancer cells, can effectively convert endogenous H 2 O 2 into highly reactive hydroxyl radicals to invoke an intensive cytotoxic effect on the cancer cells. On the other hand, catalase, present at a significantly higher concentration in normal cells than in cancer cells, remarkably can impede the apoptotic cell death induced by the internalized SnFe 2 O 4 nanocrystals. According to the results obtained from the in vitro cytotoxicity study, the relevant oxidative attacks were effectively suppressed by the presence of normal physiological levels of catalase. The SnFe 2 O 4 nanocrystals were thus proved to effect apoptotic cancer cell death through the heterogeneous Fenton reaction and were benign to cells possessing normal physiological levels of catalase. The catalase modulation of the involved heterogeneous Fenton reaction plays the key role in achieving selective cancer cell eradication for the heterogeneous Fenton reaction-driven cancer cell treatment.

Antagonism between apoptotic (Bax/Bcl-2) and anti-apoptotic (IAP) signals in human osteoblastic cells under vector-averaged gravity condition.

PubMed

Nakamura, Hiroshi; Kumei, Yasuhiro; Morita, Sadao; Shimokawa, Hitoyata; Ohya, Keiichi; Shinomiya, Kenichi

2003-12-01

A functional disorder associated with weightlessness is well documented in osteoblasts. The apototic features of this disorder are poorly understood. Harmful stress induces apoptosis in cells via mitochondria and/or Fas. The Bax triggers cytochrome c release from mitochondria, which can be blocked by the Bcl-2. Released cytochrome c then activates the initiator caspase, caspase-9, which can be blocked by the anti-apototic (IAP) family of molecules. The effector caspase, caspase-3, finally exerts DNA fragmentation. We conducted this study to examine the apoptotic effects of vector-averaged gravity on normal human osteoblastic cells. Cell culture flasks were incubated on the clinostat, which generated vector-averaged gravity condition (simulated microgravity) for 12, 24, 48, and 96 hours. Upon termination of clinostat cultures, the cell number and cell viability were assessed. DNA fragmentation was analyzed on the agarose-gel electrophoresis. The mRNA levels for Bax, Bcl-2, XIAP, and caspase-3 genes were analyzed by semi-quantitative RT-PCR. Twenty-four hours after starting clinostat rotation, the ratios of Bax/Bcl-2 mRNA levels (indicator of apoptosis) were significantly increased to 136% of the 1G static controls. However, the XIAP mRNA levels (anti-apoptotic molecule) were increased concomitantly to 138% of the 1G static controls. Thus, cell proliferation or cell viability was not affected by vector-averaged gravity. DNA fragmentation was not observed in clinostat group as well as in control group. Finally, the caspase-3 mRNA levels were not affected by vector-averaged gravity. Simulated microgravity might modulate some apoptotic signals upstream the mitochondrial pathway.

Targeting Toll-like receptor 7/8 enhances uptake of apoptotic leukemic cells by monocyte-derived dendritic cells but interferes with subsequent cytokine-induced maturation.

PubMed

van den Ancker, Willemijn; van Luijn, Marvin M; Ruben, Jurjen M; Westers, Theresia M; Bontkes, Hetty J; Ossenkoppele, Gert J; de Gruijl, Tanja D; van de Loosdrecht, Arjan A

2011-01-01

Therapeutic vaccination with dendritic cells (DC) is an emerging investigational therapy for eradication of minimal residual disease in acute myeloid leukemia. Various strategies are being explored in manufacturing DC vaccines ex vivo, e.g., monocyte-derived DC (MoDC) loaded with leukemia-associated antigens (LAA). However, the optimal source of LAA and the choice of DC-activating stimuli are still not well defined. Here, loading with leukemic cell preparations (harboring both unknown and known LAA) was explored in combination with a DC maturation-inducing cytokine cocktail (CC; IL-1β, IL-6, TNF-α, and PGE(2)) and Toll-like receptor ligands (TLR-L) to optimize uptake. Since heat shock induced apoptotic blasts were more efficiently taken up than lysates, we focused on uptake of apoptotic leukemic cells. Uptake of apoptotic blast was further enhanced by the TLR7/8-L R848 (20-30%); in contrast, CC-induced maturation inhibited uptake. CC, and to a lesser extent R848, enhanced the ability of MoDC to migrate and stimulate T cells. Furthermore, class II-associated invariant chain peptide expression was down-modulated after R848- or CC-induced maturation, indicating enhanced processing and presentation of antigenic peptides. To improve both uptake and maturation, leukemic cells and MoDC were co-incubated with R848 for 24 h followed by addition of CC. However, this approach interfered with CC-mediated MoDC maturation as indicated by diminished migratory and T cell stimulatory capacity, and the absence of IL-12 production. Taken together, our data demonstrate that even though R848 improved uptake of apoptotic leukemic cells, the sequential use of R848 and CC is counter-indicated due to its adverse effects on MoDC maturation.

Oncogenic properties of apoptotic tumor cells in aggressive B cell lymphoma.

PubMed

Ford, Catriona A; Petrova, Sofia; Pound, John D; Voss, Jorine J L P; Melville, Lynsey; Paterson, Margaret; Farnworth, Sarah L; Gallimore, Awen M; Cuff, Simone; Wheadon, Helen; Dobbin, Edwina; Ogden, Carol Anne; Dumitriu, Ingrid E; Dunbar, Donald R; Murray, Paul G; Ruckerl, Dominik; Allen, Judith E; Hume, David A; van Rooijen, Nico; Goodlad, John R; Freeman, Tom C; Gregory, Christopher D

2015-03-02

Cells undergoing apoptosis are known to modulate their tissue microenvironments. By acting on phagocytes, notably macrophages, apoptotic cells inhibit immunological and inflammatory responses and promote trophic signaling pathways. Paradoxically, because of their potential to cause death of tumor cells and thereby militate against malignant disease progression, both apoptosis and tumor-associated macrophages (TAMs) are often associated with poor prognosis in cancer. We hypothesized that, in progression of malignant disease, constitutive loss of a fraction of the tumor cell population through apoptosis could yield tumor-promoting effects. Here, we demonstrate that apoptotic tumor cells promote coordinated tumor growth, angiogenesis, and accumulation of TAMs in aggressive B cell lymphomas. Through unbiased "in situ transcriptomics" analysis-gene expression profiling of laser-captured TAMs to establish their activation signature in situ-we show that these cells are activated to signal via multiple tumor-promoting reparatory, trophic, angiogenic, tissue remodeling, and anti-inflammatory pathways. Our results also suggest that apoptotic lymphoma cells help drive this signature. Furthermore, we demonstrate that, upon induction of apoptosis, lymphoma cells not only activate expression of the tumor-promoting matrix metalloproteinases MMP2 and MMP12 in macrophages but also express and process these MMPs directly. Finally, using a model of malignant melanoma, we show that the oncogenic potential of apoptotic tumor cells extends beyond lymphoma. In addition to its profound tumor-suppressive role, apoptosis can potentiate cancer progression. These results have important implications for understanding the fundamental biology of cell death, its roles in malignant disease, and the broader consequences of apoptosis-inducing anti-cancer therapy. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Modulation of glucocorticoid resistance in pediatric T-cell Acute Lymphoblastic Leukemia by increasing BIM expression with the PI3K/mTOR inhibitor BEZ235

PubMed Central

Hall, Connor P.; Reynolds, C. Patrick; Kang, Min H.

2015-01-01

Purpose The aim of our study is to evaluate the preclinical therapeutic activity and mechanism of action of BEZ235, a dual PI3K/mTOR inhibitor, in combination with dexamethasone in ALL. Experimental Design The cytotoxic effects of BEZ235 and dexamethasone as single agents and in combination were assessed in a panel of ALL cell lines and xenograft models. The underlying mechanism of BEZ235 and dexamethasone was evaluated using immunoblotting, TaqMan RT-PCR, siRNA, immunohistochemistry and immunoprecipitation. Results Inhibition of the PI3K/AKT/mTOR pathway with the dual PI3K/mTOR inhibitor BEZ235 enhanced dexamethasone-induced anti-leukemic activity in in vitro (continuous cell lines and primary ALL cultures) and systemic in vivo models of T-ALL (including a patient-derived xenograft). Through inhibition of AKT1, BEZ235 was able to alleviate AKT1-mediated suppression of dexamethasone-induced apoptotic pathways leading to increased expression of the pro-apoptotic BCL-2 protein BIM. Downregulation of MCL-1 by BEZ235 further contributed to the modulation of dexamethasone resistance by increasing the amount of BIM available to induce apoptosis, especially in PTEN-null T-ALL where inhibition of AKT only partially overcame AKT-induced BIM suppression. Conclusion Our data support the further investigation of agents targeting the PI3K/mTOR pathway to modulate glucocorticoid resistance in T-ALL. PMID:26080839

The glycan-binding protein galectin-1 controls survival of epithelial cells along the crypt-villus axis of small intestine

PubMed Central

Muglia, C; Mercer, N; Toscano, M A; Schattner, M; Pozner, R; Cerliani, J P; Gobbi, R Papa; Rabinovich, G A; Docena, G H

2011-01-01

Intestinal epithelial cells serve as mechanical barriers and active components of the mucosal immune system. These cells migrate from the crypt to the tip of the villus, where different stimuli can differentially affect their survival. Here we investigated, using in vitro and in vivo strategies, the role of galectin-1 (Gal-1), an evolutionarily conserved glycan-binding protein, in modulating the survival of human and mouse enterocytes. Both Gal-1 and its specific glyco-receptors were broadly expressed in small bowel enterocytes. Exogenous Gal-1 reduced the viability of enterocytes through apoptotic mechanisms involving activation of both caspase and mitochondrial pathways. Consistent with these findings, apoptotic cells were mainly detected at the tip of the villi, following administration of Gal-1. Moreover, Gal-1-deficient (Lgals1−/−) mice showed longer villi compared with their wild-type counterparts in vivo. In an experimental model of starvation, fasted wild-type mice displayed reduced villi and lower intestinal weight compared with Lgals1−/− mutant mice, an effect reflected by changes in the frequency of enterocyte apoptosis. Of note, human small bowel enterocytes were also prone to this pro-apoptotic effect. Thus, Gal-1 is broadly expressed in mucosal tissue and influences the viability of human and mouse enterocytes, an effect which might influence the migration of these cells from the crypt, the integrity of the villus and the epithelial barrier function. PMID:21614093

Micro-Economics of Apoptosis in Cancer: ncRNAs Modulation of BCL-2 Family Members

PubMed Central

Villanova, Lidia; Careccia, Silvia; De Maria, Ruggero

2018-01-01

In the last few years, non-coding RNAs (ncRNAs) have been a hot topic in cancer research. Many ncRNAs were found to regulate the apoptotic process and to play a role in tumor cell resistance to treatment. The apoptotic program is on the frontline as self-defense from cancer onset, and evasion of apoptosis has been classified as one of the hallmarks of cancer responsible for therapy failure. The B-cell lymphoma 2 (BCL-2) family members are key players in the regulation of apoptosis and mediate the activation of the mitochondrial death machinery in response to radiation, chemotherapeutic agents and many targeted therapeutics. The balance between the pro-survival and the pro-apoptotic BCL-2 proteins is strictly controlled by ncRNAs. Here, we highlight the most common mechanisms exerted by microRNAs, long non-coding RNAs and circular RNAs on the main mediators of the intrinsic apoptotic cascade with particular focus on their significance in cancer biology. PMID:29570632

Micro-Economics of Apoptosis in Cancer: ncRNAs Modulation of BCL-2 Family Members.

PubMed

Villanova, Lidia; Careccia, Silvia; De Maria, Ruggero; Fiori, Micol E

2018-03-23

In the last few years, non-coding RNAs (ncRNAs) have been a hot topic in cancer research. Many ncRNAs were found to regulate the apoptotic process and to play a role in tumor cell resistance to treatment. The apoptotic program is on the frontline as self-defense from cancer onset, and evasion of apoptosis has been classified as one of the hallmarks of cancer responsible for therapy failure. The B-cell lymphoma 2 (BCL-2) family members are key players in the regulation of apoptosis and mediate the activation of the mitochondrial death machinery in response to radiation, chemotherapeutic agents and many targeted therapeutics. The balance between the pro-survival and the pro-apoptotic BCL-2 proteins is strictly controlled by ncRNAs. Here, we highlight the most common mechanisms exerted by microRNAs, long non-coding RNAs and circular RNAs on the main mediators of the intrinsic apoptotic cascade with particular focus on their significance in cancer biology.

CD300b regulates the phagocytosis of apoptotic cells via phosphatidylserine recognition

PubMed Central

Murakami, Y; Tian, L; Voss, O H; Margulies, D H; Krzewski, K; Coligan, J E

2014-01-01

The CD300 receptor family members are a group of molecules that modulate a variety of immune cell processes. We show that mouse CD300b (CLM7/LMIR5), expressed on myeloid cells, recognizes outer membrane-exposed phosphatidylserine (PS) and does not, as previously reported, directly recognize TIM1 or TIM4. CD300b accumulates in phagocytic cups along with F-actin at apoptotic cell contacts, thereby facilitating their engulfment. The CD300b-mediated activation signal is conveyed through CD300b association with the adaptor molecule DAP12, and requires a functional DAP12 ITAM motif. Binding of apoptotic cells promotes the activation of the PI3K-Akt kinase pathway in macrophages, while silencing of CD300b expression diminishes PI3K-Akt kinase activation and impairs efferocytosis. Collectively, our data show that CD300b recognizes PS as a ligand, and regulates the phagocytosis of apoptotic cells via the DAP12 signaling pathway. PMID:25034781

Modulation of the Unfolded Protein Response by Tauroursodeoxycholic Acid Counteracts Apoptotic Cell Death and Fibrosis in a Mouse Model for Secondary Biliary Liver Fibrosis

PubMed Central

Paridaens, Annelies; Raevens, Sarah; Devisscher, Lindsey; Bogaerts, Eliene; Verhelst, Xavier; Hoorens, Anne; van Vlierberghe, Hans; Van Grunsven, Leo A.; Geerts, Anja; Colle, Isabelle

2017-01-01

The role of endoplasmic reticulum stress and the unfolded protein response (UPR) in cholestatic liver disease and fibrosis is not fully unraveled. Tauroursodeoxycholic acid (TUDCA), a hydrophilic bile acid, has been shown to reduce endoplasmic reticulum (ER) stress and counteract apoptosis in different pathologies. We aimed to investigate the therapeutic potential of TUDCA in experimental secondary biliary liver fibrosis in mice, induced by common bile duct ligation. The kinetics of the hepatic UPR and apoptosis during the development of biliary fibrosis was studied by measuring markers at six different timepoints post-surgery by qPCR and Western blot. Next, we investigated the therapeutic potential of TUDCA, 10 mg/kg/day in drinking water, on liver damage (AST/ALT levels) and fibrosis (Sirius red-staining), in both a preventive and therapeutic setting. Common bile duct ligation resulted in the increased protein expression of CCAAT/enhancer-binding protein homologous protein (CHOP) at all timepoints, along with upregulation of pro-apoptotic caspase 3 and 12, tumor necrosis factor receptor superfamily, member 1A (TNFRsf1a) and Fas-Associated protein with Death Domain (FADD) expression. Treatment with TUDCA led to a significant reduction of liver fibrosis, accompanied by a slight reduction of liver damage, decreased hepatic protein expression of CHOP and reduced gene and protein expression of pro-apoptotic markers. These data indicate that TUDCA exerts a beneficial effect on liver fibrosis in a model of cholestatic liver disease, and suggest that this effect might, at least in part, be attributed to decreased hepatic UPR signaling and apoptotic cell death. PMID:28117681

Curcumin induces ER stress-mediated apoptosis through selective generation of reactive oxygen species in cervical cancer cells.

PubMed

Kim, Boyun; Kim, Hee Seung; Jung, Eun-Ji; Lee, Jung Yun; K Tsang, Benjamin; Lim, Jeong Mook; Song, Yong Sang

2016-05-01

Prolonged accumulation of misfolded or unfolded proteins caused by cellular stress, including oxidative stress, induces endoplasmic reticulum stress, which then activates an unfolded protein response (UPR). ER stress is usually maintained at higher levels in cancer cells as compared to normal cells due to altered metabolism in cancer. Here, we investigated whether curcumin is ER stress-mediated apoptosis in cervical cancer cells, and ROS increased by curcumin are involved in the process as an upstream contributor. Curcumin inhibited proliferation of cervical cancer cells (C33A, CaSki, HeLa, and ME180) and induced apoptotic cell death. Curcumin activated ER-resident UPR sensors, such as PERK, IRE-1α, and ATF6, and their downstream-signaling proteins in cervical cancer cells, but not in normal epithelial cells and peripheral blood mononuclear cells (PBMCs). CHOP, a key factor involved in ER stress-mediated apoptosis, was also activated by curcumin. CHOP decreased the ratio of anti-apoptotic protein Bcl-2 to pro-apoptotic protein Bax expression, and subsequently increased the apoptotic population of cervical cancer cells. Furthermore, curcumin elevated levels of intracellular reactive oxygen species (ROS) in cervical cancer cells, but not in normal epithelial cells. Scavenging ROS resulted in inhibition of ER stress and partially restored cell viability in curcumin-treated cancer cells. Collectively, these observations show that curcumin promotes ER stress-mediated apoptosis in cervical cancer cells through increase of cell type-specific ROS generation. Therefore, modulation of these differential responses to curcumin between normal and cervical cancer cells could be an effective therapeutic strategy without adverse effects on normal cells. © 2015 Wiley Periodicals, Inc.

The study of apoptotic bifunctional effects in relationship between host and parasite in cystic echinococcosis: a new approach to suppression and survival of hydatid cyst.

PubMed

Spotin, Adel; Majdi, Monireh Mokhtari Amir; Sankian, Mojtaba; Varasteh, Abdolreza

2012-05-01

Cystic echinococcosis (hydatidosis) is a zoonotic helminthic disease of human and other intermediated hosts wherein infection is caused by the larval stages of tapeworm Echinococcus granulosus. Growth of the larval stage is formed throughout the internal organs, the liver and lung, causing their destruction. Important pathways are unknown about suppression and survival of cysts in human body. In this study, apoptotic bifunctional effects are evaluated in relationship between host and parasite in cystic echinococcosis. Human lymphocytes were treated with hydatid fluid (HF). After 6 h of exposure, caspase-3 activity was measured by fluorometric assay in the HF-treated lymphocytes and control cells. Also, the expression of Bax (as pro-apoptotic protein) and Bcl-2 (an anti-apoptotic protein) mRNA was assessed by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) after 12 h of exposure. For surveying of apoptosis-inducing ligands TNF-related apoptosis-inducing ligand and Fas-L, germinal layer and accompaniment peripheral tissues as healthy control were separated by scalpel from each cyst in sterile condition, then were assess by semiquantitative RT-PCR method in mRNA expression. Both the ratio of Bax/Bcl-2 mRNA expression and caspase-3 activity were higher in the fertile fluid-treated lymphocytes relative to infertile fluid-treated lymphocytes and control group versus the expression level of apoptosis-inducing ligands having a relatively high level in germinal layer of infertile cyst in comparison to fertile cyst and healthy tissue. Apoptosis of germinal layer of fertile cysts is possibly one of the suppression mechanisms in hydatidosis patients, in contrast to lymphocytes apoptosis by modulator of hydatid fluid, one of the hydatid cyst survival mechanisms.

Estrogen Modulates Specific Life and Death Signals Induced by LH and hCG in Human Primary Granulosa Cells In Vitro.

PubMed

Casarini, Livio; Riccetti, Laura; De Pascali, Francesco; Gilioli, Lisa; Marino, Marco; Vecchi, Eugenia; Morini, Daria; Nicoli, Alessia; La Sala, Giovanni Battista; Simoni, Manuela

2017-04-28

Luteinizing hormone (LH) and human chorionic gonadotropin (hCG) are glycoprotein hormones used for assisted reproduction acting on the same receptor (LHCGR) and mediating different intracellular signaling. We evaluated the pro- and anti-apoptotic effect of 100 pM LH or hCG, in the presence or in the absence of 200 pg/mL 17β-estradiol, in long-term, serum-starved human primary granulosa cells (hGLC) and a transfected granulosa cell line overexpressing LHCGR (hGL5/LHCGR). To this purpose, phospho-extracellular-regulated kinase 1/2 (pERK1/2), protein kinase B (pAKT), cAMP-responsive element binding protein (pCREB) activation and procaspase 3 cleavage were evaluated over three days by Western blotting, along with the expression of target genes by real-time PCR and cell viability by colorimetric assay. We found that LH induced predominant pERK1/2 and pAKT activation STARD1 , CCND2 and anti-apoptotic XIAP gene expression, while hCG mediated more potent CREB phosphorylation, expression of CYP19A1 and procaspase 3 cleavage than LH. Cell treatment by LH is accompanied by increased (serum-starved) cell viability, while hCG decreased the number of viable cells. The hCG-specific, pro-apoptotic effect was blocked by a physiological dose of 17β-estradiol, resulting in pAKT activation, lack of procaspase 3 cleavage and increased cell viability. These results confirm that relatively high levels of steroidogenic pathway activation are linked to pro-apoptotic signals in vitro, which may be counteracted by other factors, i.e., estrogens.

SL-01, an oral derivative of gemcitabine, inhibited human breast cancer growth through induction of apoptosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Yuan-Yuan; Qin, Yi-Zhuo; Wang, Rui-Qi

Highlights: •SL-01 is an oral derivative of gemcitabine. •SL-01 possessed activity against human breast cancer growth via apoptotic induction. •SL-01’s activity was more potently than that of gemcitabine. •SL-01 inhibited cancer growth without toxicity to mice. -- Abstract: SL-01 is an oral derivative of gemcitabine that was synthesized by introducing the moiety of 3-(dodecyloxycarbonyl) pyrazine-2-carbonyl at N4-position on cytidine ring of gemcitabine. We aimed to evaluate the efficacy of SL-01 on human breast cancer growth. SL-01 significantly inhibited MCF-7 proliferation as estimated by colorimetric assay. Flow cytometry assay indicated the apoptotic induction and cell cycle arrest in G1 phase. SL-01more » modulated the expressions of p-ATM, p53 and p21 and decrease of cyclin D1 in MCF-7 cells. Further experiments were performed in a MCF-7 xenografts mouse model. SL-01 by oral administration strongly inhibited MCF-7 xenografts growth. This effect of SL-01 might arise from its roles in the induction of apoptosis. Immunohistochemistry assay showed the increase of TUNEL staining cells. Western blotting indicated the modulation of apoptotic proteins in SL-01-treated xenografts. During the course of study, there was no evidence of toxicity to mice. In contrast, the decrease of neutrophil cells in peripheral and increase of AST and ALT levels in serum were observed in the gemcitabine-treated mice. Conclusion: SL-01 possessed similar activity against human breast cancer growth with gemcitabine, whereas, with lower toxicity to gemcitabine. SL-01 is a potent oral agent that may supplant the use of gemcitabine.« less

Small heat shock proteins: Role in cellular functions and pathology.

PubMed

Bakthisaran, Raman; Tangirala, Ramakrishna; Rao, Ch Mohan

2015-04-01

Small heat shock proteins (sHsps) are conserved across species and are important in stress tolerance. Many sHsps exhibit chaperone-like activity in preventing aggregation of target proteins, keeping them in a folding-competent state and refolding them by themselves or in concert with other ATP-dependent chaperones. Mutations in human sHsps result in myopathies, neuropathies and cataract. Their expression is modulated in diseases such as Alzheimer's, Parkinson's and cancer. Their ability to bind Cu2+, and suppress generation of reactive oxygen species (ROS) may have implications in Cu2+-homeostasis and neurodegenerative diseases. Circulating αB-crystallin and Hsp27 in the plasma may exhibit immunomodulatory and anti-inflammatory functions. αB-crystallin and Hsp20 exhitbit anti-platelet aggregation: these beneficial effects indicate their use as potential therapeutic agents. sHsps have roles in differentiation, proteasomal degradation, autophagy and development. sHsps exhibit a robust anti-apoptotic property, involving several stages of mitochondrial-mediated, extrinsic apoptotic as well as pro-survival pathways. Dynamic N- and C-termini and oligomeric assemblies of αB-crystallin and Hsp27 are important factors for their functions. We propose a "dynamic partitioning hypothesis" for the promiscuous interactions and pleotropic functions exhibited by sHsps. Stress tolerance and anti-apoptotic properties of sHsps have both beneficial and deleterious consequences in human health and diseases. Conditional and targeted modulation of their expression and/or activity could be used as strategies in treating several human disorders. The review attempts to provide a critical overview of sHsps and their divergent roles in cellular processes particularly in the context of human health and disease. Copyright © 2015. Published by Elsevier B.V.

Natural products induce a G protein-mediated calcium pathway activating p53 in cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ginkel, Paul R. van; Yan, Michael B.; Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53792

Paclitaxel, etoposide, vincristine and doxorubicin are examples of natural products being used as chemotherapeutics but with adverse side effects that limit their therapeutic window. Natural products derived from plants and having low toxicity, such as quercetin, resveratrol, epigallocatechin gallate and piceatannol, have been shown to inhibit tumor cell growth both in vitro and in pre-clinical models of cancer, but their mechanisms of action have not been fully elucidated, thus restricting their use as prototypes for developing synthetic analogs with improved anti-cancer properties. We and others have demonstrated that one of the earliest and consistent events upon exposure of tumor cellsmore » to these less toxic natural products is a rise in cytoplasmic calcium, activating several pro-apoptotic pathways. We describe here a G protein/inositol 1,4,5-trisphosphate pathway (InsP3) in MDA-MB-231 human breast cancer cells that mediates between these less toxic natural products and the release of calcium from the endoplasmic reticulum. Further, we demonstrate that this elevation of intracellular calcium modulates p53 activity and the subsequent transcription of several pro-apoptotic genes encoding PIG8, CD95, PIDD, TP53INP, RRM2B, Noxa, p21 and PUMA. We conclude from our findings that less toxic natural products likely bind to a G protein coupled receptor that activates a G protein-mediated and calcium-dependent pathway resulting selectively in tumor cell death. - Highlights: • Natural products having low toxicity increase cytoplasmic calcium in cancer cells. • A G-protein/IP{sub 3} pathway mediates the release of calcium from the ER. • The elevation of intracellular calcium modulates p53 activity. • p53 and other Ca{sup 2+}-dependent pro-apoptotic pathways inhibit cancer cell growth.« less

Mitochondrial Modulation by Epigallocatechin 3-Gallate Ameliorates Cisplatin Induced Renal Injury through Decreasing Oxidative/Nitrative Stress, Inflammation and NF-kB in Mice

PubMed Central

Wang, Xueping; Wang, Ping; Fu, Guanghou; Meng, Hongzhou; Wang, Yimin; Jin, Baiye

2015-01-01

Cancer chemotherapy drug cisplatin is known for its nephrotoxicity. The aim of this study is to investigate whether Epigallocatechin 3-Gallate (EGCG) can reduce cisplatin mediated side effect in kidney and to understand its mechanism of protection against tissue injury. We used a well-established 3-day cisplatin induced nephrotoxicity mice model where EGCG were administered. EGCG is a major active compound in Green Tea and have strong anti-oxidant and anti-inflammatory properties. EGCG protected against cisplatin induced renal dysfunction as measured by serum creatinine and blood urea nitrogen (BUN). EGCG improved cisplatin induced kidney structural damages such as tubular dilatation, cast formation, granulovaculoar degeneration and tubular cell necrosis as evident by PAS staining. Cisplatin induced kidney specific mitochondrial oxidative stress, impaired activities of mitochondrial electron transport chain enzyme complexes, impaired anti-oxidant defense enzyme activities such as glutathione peroxidase (GPX) and manganese superoxide dismutase (MnSOD) in mitochondria, inflammation (tumor necrosis factor α and interleukin 1β), increased accumulation of NF-κB in nuclear fraction, p53 induction, and apoptotic cell death (caspase 3 activity and DNA fragmentation). Treatment of mice with EGCG markedly attenuated cisplatin induced mitochondrial oxidative/nitrative stress, mitochondrial damages to electron transport chain activities and antioxidant defense enzyme activities in mitochondria. These mitochondrial modulations by EGCG led to protection mechanism against cisplatin induced inflammation and apoptotic cell death in mice kidney. As a result, EGCG improved renal function in cisplatin mediated kidney damage. In addition to that, EGCG attenuated cisplatin induced apoptotic cell death and mitochondrial reactive oxygen species (ROS) generation in human kidney tubular cell line HK-2. Thus, our data suggest that EGCG may represent new promising adjunct candidate for cisplatin. PMID:25875356

Molecular dynamics study of segment peptides of Bax, Bim, and Mcl-1 BH3 domain of the apoptosis-regulating proteins bound to the anti-apoptotic Mcl-1 protein.

PubMed

Zhao, Run-Ning; Fan, Song; Han, Ju-Guang; Liu, Guang

2015-01-01

Mcl-1 has emerged as a potential therapeutic target in the treatment of several malignancies. Peptides representing BH3 region of pro-apoptotic proteins have been shown to bind the hydrophobic cleft of anti-apoptotic Mcl-1 and this segment is responsible for modulating the apoptotic pathways in living cells. Understanding the molecular basis of protein-peptide interaction is required to develop potent inhibitors specific for Mcl-1. Molecular dynamics simulations were performed for Mcl-1 in complex with three different BH3 peptides derived from Mcl-1, Bax, and Bim. Accordingly, the calculated binding free energies using MM-PBSA method are obtained and comparison with the experimentally determined binding free energies is made. The interactions involving two conserved charged residues (Aspi, and Arg/Lysi-4) and three upstream conserved hydrophobic residues (Leui-5, Ile/Vali-2, and Glyi-1, respectively) of BH3 peptides play the important roles in the structural stability of the complexes. The calculated results exhibit that the interactions of Bim BH3 peptides to Mcl-1 is stronger than the complex with Bax 19BH3 peptides. The hydrophobic residues (position i - 9, i - 8 and i + 2) of BH3 peptides can be involved in their inhibitory specificity. The calculated results can be used for designing more effective MCL-1 inhibitors.

Houttuynia cordata Thunb extract modulates G0/G1 arrest and Fas/CD95-mediated death receptor apoptotic cell death in human lung cancer A549 cells

PubMed Central

2013-01-01

Background Houttuynia cordata Thunb (HCT) is commonly used in Taiwan and other Asian countries as an anti-inflammatory, antibacterial and antiviral herbal medicine. In this study, we investigated the anti-human lung cancer activity and growth inhibition mechanisms of HCT in human lung cancer A549 cells. Results In order to investigate effects of HCT on A549 cells, MTT assay was used to evaluate cell viability. Flow cytometry was employed for cell cycle analysis, DAPI staining, and the Comet assay was used for DNA fragmentation and DNA condensation. Western blot analysis was used to analyze cell cycle and apoptotic related protein levels. HCT induced morphological changes including cell shrinkage and rounding. HCT increased the G0/G1 and Sub-G1 cell (apoptosis) populations and HCT increased DNA fragmentation and DNA condensation as revealed by DAPI staining and the Comet assay. HCT induced activation of caspase-8 and caspase-3. Fas/CD95 protein levels were increased in HCT-treated A549 cells. The G0/G1 phase and apoptotic related protein levels of cyclin D1, cyclin A, CDK 4 and CDK 2 were decreased, and p27, caspase-8 and caspase-3 were increased in A549 cells after HCT treatment. Conclusions The results demonstrated that HCT-induced G0/G1 phase arrest and Fas/CD95-dependent apoptotic cell death in A549 cells PMID:23506616

[Apoptosis-modulating effects of heat shock proteins: the influence of Hsp27 chaperone on TBA Bcl-2 family proteins in Jurkat cell line].

PubMed

Riazantseva, N V; Kaĭgorodova, E V; Maroshkina, A N; Belkina, M V; Novitskiĭ, V V

2012-01-01

The in vitro phosphorylated and non-phosphorylated Hsp27 forms concentrations and Bcl-2 proteins affected by Hsp27 inhibition were studied in Jurkat-line tumor cells and healthy donor mononuclear lymphocytes by Western blotting technique. The Hsp27 inhibition causes the increase of intracellular Bax protein concentration and the decrease of Bcl-2 level leading to an increase of apoptotic changes in Jurkat line cells.

In non-transformed cells Bak activates upon loss of anti-apoptotic Bcl-XL and Mcl-1 but in the absence of active BH3-only proteins.

PubMed

Senft, D; Weber, A; Saathoff, F; Berking, C; Heppt, M V; Kammerbauer, C; Rothenfusser, S; Kellner, S; Kurgyis, Z; Besch, R; Häcker, G

2015-11-26

Mitochondrial apoptosis is controlled by proteins of the B-cell lymphoma 2 (Bcl-2) family. Pro-apoptotic members of this family, known as BH3-only proteins, initiate activation of the effectors Bcl-2-associated X protein (Bax) and Bcl-2 homologous antagonist/killer (Bak), which is counteracted by anti-apoptotic family members. How the interactions of Bcl-2 proteins regulate cell death is still not entirely clear. Here, we show that in the absence of extrinsic apoptotic stimuli Bak activates without detectable contribution from BH3-only proteins, and cell survival depends on anti-apoptotic Bcl-2 molecules. All anti-apoptotic Bcl-2 proteins were targeted via RNA interference alone or in combinations of two in primary human fibroblasts. Simultaneous targeting of B-cell lymphoma-extra large and myeloid cell leukemia sequence 1 led to apoptosis in several cell types. Apoptosis depended on Bak whereas Bax was dispensable. Activator BH3-only proteins were not required for apoptosis induction as apoptosis was unaltered in the absence of all BH3-only proteins known to activate Bax or Bak directly, Bcl-2-interacting mediator of cell death, BH3-interacting domain death agonist and p53-upregulated modulator of apoptosis. These findings argue for auto-activation of Bak in the absence of anti-apoptotic Bcl-2 proteins and provide evidence of profound differences in the activation of Bax and Bak.

Tangeretin alters neuronal apoptosis and ameliorates the severity of seizures in experimental epilepsy-induced rats by modulating apoptotic protein expressions, regulating matrix metalloproteinases, and activating the PI3K/Akt cell survival pathway.

PubMed

Guo, Xiao-Qian; Cao, Yu-Ling; Hao, Fang; Yan, Zhong-Rui; Wang, Mei-Ling; Liu, Xue-Wu

2017-09-01

Epilepsy is complex neural disarray categorized by recurring seizures. Despite recent advances in pharmacotherapies for epilepsy, its treatment remains a challenge due to the contrary effects of the drugs. As a result, the identification of novel anti-epileptic drugs (AEDs) with neuroprotective properties and few side effects is of great value. Thus, the present study assessed the treatment effects of tangeretin using a rat model of pilocarpine-induced epilepsy. Separate groups of male Wistar rats received oral administrations of tangeretin at 50, 100, or 200mg/kg for 10 days and then, on the 10th day, they received an intraperitoneal injection of pilocarpine (30mg/kg). Subsequently, neuronal degeneration and apoptosis were assessed using Nissl staining and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay procedures. Additionally, the expressions of phosphatidylinositol-3-kinase (PI3K/Akt) pathway proteins, cleaved caspase-3, Bad, Bcl-2, Bcl-xL, and Bax were determined using Western blot analyses. Tangeretin reduced the seizure scores and latency to first seizure of the rats and effectively activated the pilocarpine-induced suppression of PI3K/Akt signaling. Additionally, tangeretin effectively regulated the levels of apoptosis-inducing factor (AIF) in mitochondria as well as the expressions of apoptotic pathway proteins. Seizure-induced elevations in the activities and expressions of matrix metalloproteinases (MMPs)-2 and -9 were also modulated. The present results indicate that tangeretin exerted potent neuroprotective effects against pilocarpine-induced seizures via the activation of PI3K/Akt signaling and the regulation of MMPs. Copyright © 2017 Medical University of Bialystok. Published by Elsevier B.V. All rights reserved.

Induction of apoptosis by 3-amino-6-(3-aminopropyl)-5,6-dihydro-5,11-dioxo-11H-indeno[1,2-c]isoquinoline via modulation of MAPKs (p38 and c-Jun N-terminal kinase) and c-Myc in HL-60 human leukemia cells.

PubMed

Park, Eun-Jung; Kiselev, Evgeny; Conda-Sheridan, Martin; Cushman, Mark; Pezzuto, John M

2012-03-23

Recently, we reported that 3-amino-6-(3-aminopropyl)-5,6-dihydro-5,11-dioxo-11H-indeno[1,2-c]isoquinoline (AM6-36), sharing structural similarity with naturally occurring isoquinolines, induced activities mediated by retinoid X receptor (RXR) response element accompanied by antiproliferative effects on breast cancer cells. To further characterize the biologic potential of AM6-36, we currently report studies conducted with HL-60 human leukemia cells. AM6-36 significantly inhibited cellular proliferation in a dose- and time-dependent manner with an IC(50) value of 86 nM. When evaluated at low test concentrations (≤0.25 μM), AM6-36 induced arrest in the G2/M phase of the cell cycle. At higher concentrations (1 and 2 μM), the response shifted to apoptosis, which was consistent with the effect of AM6-36 on other apoptotic signatures including an increase of apoptotic annexin V(+) 7-AAD(-) cells, loss of mitochondrial membrane potential, induction of poly(ADP-ribose) polymerase cleavage, and activation of several caspases. These apoptotic effects are potentially due to up-regulation of p38 MAPK and JNK phosphorylation and down-regulation of c-Myc oncogene expression. Taken together, AM6-36 might serve as an effective anticancer agent by inducing G2/M cell cycle arrest and apoptosis through the activation of MAPKs and inhibition of c-Myc.

Differential modulation of apoptotic processes by proanthocyanidins as a dietary strategy for delaying chronic pathologies.

PubMed

Puiggròs, Francesc; Salvadó, Maria-Josepa; Bladé, Cinta; Arola, Lluís

2014-01-01

Apoptosis is a biological process necessary for maintaining cellular homeostasis. Several diseases can result if it is deregulated. For example, inhibition of apoptotic signaling pathways is linked to the survival of pathological cells, which contributes to cancer, whereas excessive apoptosis is linked to neurodegenerative diseases, partially via oxidative stress. The activation or restoration of apoptosis via extrinsic or intrinsic pathways combined with cell signaling pathways triggered by reactive oxygen specises (ROS) formation is considered a key strategy by which bioactive foods can exert their health effects. Proanthocyanidins, a class of flavonoids naturally found in fruits, vegetables, and beverages, have attracted a great deal of attention not only because they are strong antioxidants but also because they appear to exert a different modulation of apoptosis, stimulating apoptosis in damaged cells, thus preventing cancer or reducing apoptosis in healthy cells, and as a result, preserving the integrity of normal cells and protecting against neurodegenerative diseases. Therefore, proanthocyanidins could provide a defense against apoptosis induced by oxidative stress or directly inhibit apoptosis, and they could also provide a promising treatment for a variety of diseases. Emerging data suggest that proanthocyanidins, especially those that humans can be persuaded to consume, may be used to prevent and manage cancer and mental disorders.

Modulation of ARTS and XIAP by Parkin Is Associated with Carnosic Acid Protects SH-SY5Y Cells against 6-Hydroxydopamine-Induced Apoptosis.

PubMed

Fu, Ru-Huei; Huang, Li-Chun; Lin, Chia-Yuan; Tsai, Chia-Wen

2018-02-01

The mediation of apoptosis-related protein in the TGF-β signaling pathway (ARTS) and X-liked inhibitor of apoptosis protein (XIAP) by parkin plays a critical role in preventing Parkinson's disease. We studied whether carnosic acid (CA) could prevent 6-hydroxydopamine (6-OHDA)-induced apoptosis by modulating ARTS and XIAP through parkin in SH-SY5Y cells. In cells treated with 6-OHDA, the protein expression of ARTS is increased and XIAP is decreased. Pretreatment of cells with CA reversed these effects. Moreover, CA attenuated the activation of caspase 9 and caspase 7 by 6-OHDA. By immunoprecipitation with ARTS antibody, we found that 6-OHDA increased the protein expression of XIAP. However, pretreatment of cells with CA reduced XIAP protein and increased the ubiquitination of ARTS. Silencing of parkin attenuated the ability of CA to reverse the induction of ARTS and apoptotic-related proteins and the reduction of XIAP and parkin protein by 6-OHDA. Similarly, reversal of 6-OHDA-induced nuclear condensation and apoptotic-related proteins by CA was inhibited in cells with XIAP silencing. In conclusion, CA induces parkin by enhancing the ubiquitination of ARTS, leading to induction of XIAP. This may be a novel strategy for preventing Parkinson's disease.

Effect of cocaine on Fas-associated protein with death domain in the rat brain: individual differences in a model of differential vulnerability to drug abuse.

PubMed

García-Fuster, María-Julia; Clinton, Sarah M; Watson, Stanley J; Akil, Huda

2009-04-01

This study was designed to (1) assess the effects of cocaine on Fas-associated protein with death domain (FADD) system and its role in the activation of apoptotic vs nonapoptotic events and (2) ascertain whether animals selectively bred for their differential propensity to drug-seeking show differences in FADD levels or response to cocaine. Acute cocaine, through D(2) dopamine receptors, induced a dose-response increase in FADD protein in the cortex, with opposite effects over pFADD (Ser191/194), and no induction of apoptotic cell death (poly-(ADP-ribose) polymerase cleavage). FADD was increased by cocaine in cytosol (approximately 142%), membranes (approximately 23%) and nucleus (approximately 54%). The modulation of the FADD system showed tolerance of the acute effect over time, as well as a compensatory response on withdrawal that mirrored the acute effect--ie a transient FADD decrease on day 3 of withdrawal, both at mRNA and protein levels. In a second experiment, possible FADD differences were investigated in rats selectively bred for differential responsiveness to novelty, propensity for drug-seeking and cocaine sensitization. High-responders (HR), who were more prone to drug abuse, exhibited higher FADD and lower pFADD levels than low-responder (LR) rats. However, HR and LR rats showed similar rates of cocaine-induced apoptosis, and exhibited a parallel impact of cocaine over FADD within each phenotype. Thus, FADD is a signaling protein modulated by cocaine, regulating apoptosis/proliferative mechanisms in relation to its FADD/pFADD content. Interestingly, animals selectively bred for differential propensity to substance abuse show basal differences in the expression of this protein, suggesting FADD may also be a molecular correlate for the HR/LR phenotype.

Eupatilin inhibits T-cell activation by modulation of intracellular calcium flux and NF-kappaB and NF-AT activity.

PubMed

Kim, Young-Dae; Choi, Suck-Chei; Oh, Tae-Young; Chun, Jang-Soo; Jun, Chang-Duk

2009-09-01

Eupatilin, one of the pharmacologically active ingredients of Artemisia princeps, exhibits a potent anti-ulcer activity, but its effects on T-cell immunity have not been investigated. Here, we show that eupatilin has a profound inhibitory effect on IL-2 production in Jurkat T cells as well as in human peripheral blood leukocytes. Eupatilin neither influenced clustering of CD3 and LFA-1 to the immunological synapse nor inhibited conjugate formation between T cells and B cells in the presence or absence of superantigen (SEE). Eupatilin also failed to inhibit T-cell receptor (TCR) internalization, thereby, suggesting that eupatilin does not interfere with TCR-mediated signals on the membrane proximal region. In unstimulated T cells, eupatilin significantly induced apoptotic cell death, as evidenced by an increased population of annexin V(+)/PI(+) cells and cleavage of caspase-3 and PARP. To our surprise, however, once cells were activated, eupatilin had little effect on apoptosis, and instead slightly protected cells from activation-induced cell death, suggesting that apoptosis also is not a mechanism for eupatilin-induced T-cell suppression. On the contrary, eupatilin dramatically inhibited I-kappaBalpha degradation and NF-AT dephosphorylation and, consequently, inhibited NF-kappaB and NF-AT promoter activities in PMA/A23187-stimulated T cells. Interestingly, intracellular calcium flux was significantly perturbed in cells pre-treated with eupatilin, suggesting that calcium-dependent cascades might be targets for eupatilin action. Collectively, our results provide evidence for dual regulatory functions of eupatilin: (1) a pro-apoptotic effect on resting T cells and (2) an immunosuppressive effect on activated T cells, presumably through modulation of Ca(2+) flux. (c) 2009 Wiley-Liss, Inc.

The Proteins from Sika deer antler as potential modulators on cisplatin-induced cytotoxicity in human embryonic kidney 293 cells.

PubMed

Yang, Huihai; Li, Wei; Wang, Lulu; He, Xiaofeng; Sun, Hang; Zhang, Jing

2017-07-31

Our study aimed to investigate the protective role of SDAPR on cisplatin-induced cytotoxicity and its' possible mechanism in HEK293 cells. Cell viability was measured by MTT assay. Oxidative stress (SOD, GSH, LDH and MDA), inflammatory factors (TNF-α and IL-6) and apoptosis-related proteins (caspase-3, Bax, Bcl-2) expression were measured. The apoptotic cells were observed by TUNEL staining. Our study results indicated that non-cytotoxic levels of SDAPR significantly increased viability rate (LD 50 value of cisplatin is 20 μM), which improved antioxidant defence, attenuated apoptosis by decreasing expression levels of cleaved-caspase-3 and Bax, increasing Bcl-2 expression and inhibiting apoptotic positive cells in HEK 293 cells. In addition, SDAPR treatment markedly inhibited the levels of TNF-α and IL-6. In conclusion, Sika deer antler protein, a potential modulator, could alleviate cisplatin-induced cytotoxicity in HEK 293 cells.

NEU3 sialidase strictly modulates GM3 levels in skeletal myoblasts C2C12 thus favoring their differentiation and protecting them from apoptosis.

PubMed

Anastasia, Luigi; Papini, Nadia; Colazzo, Francesca; Palazzolo, Giacomo; Tringali, Cristina; Dileo, Loredana; Piccoli, Marco; Conforti, Erika; Sitzia, Clementina; Monti, Eugenio; Sampaolesi, Maurilio; Tettamanti, Guido; Venerando, Bruno

2008-12-26

Membrane-bound sialidase NEU3, often referred to as the "ganglioside sialidase," has a critical regulatory function on the sialoglycosphingolipid pattern of the cell membrane, with an anti-apoptotic function, especially in cancer cells. Although other sialidases have been shown to be involved in skeletal muscle differentiation, the role of NEU3 had yet to be disclosed. Herein we report that NEU3 plays a key role in skeletal muscle differentiation by strictly modulating the ganglioside content of adjacent cells, with special regard to GM3. Induced down-regulation of NEU3 in murine C2C12 myoblasts, even when partial, totally inhibits their capability to differentiate by increasing the GM3 level above a critical point, which causes epidermal growth factor receptor inhibition (and ultimately its down-regulation) and an higher responsiveness of myoblasts to the apoptotic stimuli.

The Immunomodulatory and Neuroprotective Effects of Mesenchymal Stem Cells (MSCs) in Experimental Autoimmune Encephalomyelitis (EAE): A Model of Multiple Sclerosis (MS)

PubMed Central

Al Jumah, Mohammed A.; Abumaree, Mohamed H.

2012-01-01

Mesenchymal stem cells (MSCs) are multipotent cells that differentiate into the mesenchymal lineages of adipocytes, osteocytes and chondrocytes. MSCs can also transdifferentiate and thereby cross lineage barriers, differentiating for example into neurons under certain experimental conditions. MSCs have anti-proliferative, anti-inflammatory and anti-apoptotic effects on neurons. Therefore, MSCs were tested in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), for their effectiveness in modulating the pathogenic process in EAE to develop effective therapies for MS. The data in the literature have shown that MSCs can inhibit the functions of autoreactive T cells in EAE and that this immunomodulation can be neuroprotective. In addition, MSCs can rescue neural cells via a mechanism that is mediated by soluble factors, which provide a suitable environment for neuron regeneration, remyelination and cerebral blood flow improvement. In this review, we discuss the effectiveness of MSCs in modulating the immunopathogenic process and in providing neuroprotection in EAE. PMID:22942767

Anti-inflammatory and apoptotic effects of the polyphenol curcumin on human fibroblast-like synoviocytes.

PubMed

Kloesch, Burkhard; Becker, Tatjana; Dietersdorfer, Elisabeth; Kiener, Hans; Steiner, Guenter

2013-02-01

It has recently been reported that the polyphenol curcumin has pronounced anti-carcinogenic, anti-inflammatory and pro-apoptotic properties. This study investigated possible anti-inflammatory and apoptotic effects of curcumin on the human synovial fibroblast cell line MH7A, and on fibroblast-like synoviocytes (FLS) derived from patients with rheumatoid arthritis (RA). MH7A cells and RA-FLS were stimulated either with interleukin (IL)-1β or phorbol 12-myristate 13 acetate (PMA), and treated simultaneously or sequentially with increasing concentrations of curcumin. Release of interleukin (IL)-6 and vascular endothelial growth factor (VEGF)-A was quantified by enzyme-linked immunosorbent assays (ELISAs). In MH7A cells, modulation of the transcription factor nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinases (MAPKs) such as p38 and extracellular-signal regulated kinase (ERK1/2) were analysed by a reporter gene assay and Western blot, respectively. Pro-apoptotic events were monitored by Annexin-V/7-AAD based assay. Cleavage of pro-caspase-3 and -7 was checked with specific antibodies. Curcumin effectively blocked IL-1β and PMA-induced IL-6 expression both in MH7A cells and RA-FLS. VEGF-A expression could only be detected in RA-FLS and was induced by PMA, but not by IL-1β. Furthermore, curcumin inhibited activation of NF-κB and induced dephosphorylation of ERK1/2. Treatment of FLS with high concentrations of curcumin was associated with a decrease in cell viability and induction of apoptosis. The natural compound curcumin represents strong anti-inflammatory properties and induces apoptosis in FLS. This study provides an insight into possible molecular mechanisms of this substance and suggests it as a natural remedy for the treatment of chronic inflammatory diseases like RA. Copyright © 2013 Elsevier B.V. All rights reserved.

IGF-1 protects SH-SY5Y cells against MPP+-induced apoptosis via PI3K/PDK-1/Akt pathway.

PubMed

Kim, Chanyang; Park, Seungjoon

2018-03-01

Insulin-like growth factor (IGF)-1 is a well-known anti-apoptotic pro-survival factor and phosphatidylinositol-3-kinase (PI3K)/Akt pathway is linked to cell survival induced by IGF-1. It is also reported that Akt signaling is modulated by 3-phosphoinositide-dependent kinase-1 (PDK1). In the current study, we investigated whether the anti-apoptotic effect of IGF-1 in SH-SY5Y cells exposed to 1-methyl-4-phenylpyridinium (MPP + ) is associated with the activity of PI3K/PDK1/Akt pathway. Treatment of cells with IGF-1 inhibited MPP + -induced apoptotic cell death. IGF-1-induced activation of Akt and the protective effect of IGF-1 on MPP + -induced apoptosis were abolished by chemical inhibition of PDK1 (GSK2334470) or PI3K (LY294002). The phosphorylated levels of Akt and PDK1 were significantly suppressed after MPP + exposure, while IGF-1 treatment completely restored MPP+-induced reductions in phosphorylation. IGF-1 protected cells from MPP + insult by suppressing intracellular reactive oxygen species (ROS) production and malondialdehyde levels and increasing superoxide dismutase activity. Mitochondrial ROS levels were also increased during MPP + exposure, which were attenuated by IGF-1 treatment. In addition, IGF-1-treated cells showed increased activities of succinate dehydrogenase and citrate synthase, stabilization of mitochondrial transmembrane potential, increased ratio of Bcl-2 to Bax, prevention of cytochrome c release and inhibition of caspase-3 activation with PARP cleavage. Furthermore, the protective effects of IGF-1 on oxidative stress and mitochondrial dysfunction were attenuated when cells were preincubated with GSK2334470 or LY294002. Our data suggest that IGF-1 protects SH-SY5Y cells against MPP + -associated oxidative stress by preserving mitochondrial integrity and inhibiting mitochondrial apoptotic cascades via the activation of PI3K/PDK1/Akt pathway. © 2018 The authors.

IGF-1 protects SH-SY5Y cells against MPP+-induced apoptosis via PI3K/PDK-1/Akt pathway

PubMed Central

Kim, Chanyang; Park, Seungjoon

2018-01-01

Insulin-like growth factor (IGF)-1 is a well-known anti-apoptotic pro-survival factor and phosphatidylinositol-3-kinase (PI3K)/Akt pathway is linked to cell survival induced by IGF-1. It is also reported that Akt signaling is modulated by 3-phosphoinositide-dependent kinase-1 (PDK1). In the current study, we investigated whether the anti-apoptotic effect of IGF-1 in SH-SY5Y cells exposed to 1-methyl-4-phenylpyridinium (MPP+) is associated with the activity of PI3K/PDK1/Akt pathway. Treatment of cells with IGF-1 inhibited MPP+-induced apoptotic cell death. IGF-1-induced activation of Akt and the protective effect of IGF-1 on MPP+-induced apoptosis were abolished by chemical inhibition of PDK1 (GSK2334470) or PI3K (LY294002). The phosphorylated levels of Akt and PDK1 were significantly suppressed after MPP+ exposure, while IGF-1 treatment completely restored MPP+-induced reductions in phosphorylation. IGF-1 protected cells from MPP+ insult by suppressing intracellular reactive oxygen species (ROS) production and malondialdehyde levels and increasing superoxide dismutase activity. Mitochondrial ROS levels were also increased during MPP+ exposure, which were attenuated by IGF-1 treatment. In addition, IGF-1-treated cells showed increased activities of succinate dehydrogenase and citrate synthase, stabilization of mitochondrial transmembrane potential, increased ratio of Bcl-2 to Bax, prevention of cytochrome c release and inhibition of caspase-3 activation with PARP cleavage. Furthermore, the protective effects of IGF-1 on oxidative stress and mitochondrial dysfunction were attenuated when cells were preincubated with GSK2334470 or LY294002. Our data suggest that IGF-1 protects SH-SY5Y cells against MPP+-associated oxidative stress by preserving mitochondrial integrity and inhibiting mitochondrial apoptotic cascades via the activation of PI3K/PDK1/Akt pathway. PMID:29459421

Perinatal asphyxia leads to PARP-1 overactivity, p65 translocation, IL-1β and TNF-α overexpression, and apoptotic-like cell death in mesencephalon of neonatal rats: prevention by systemic neonatal nicotinamide administration.

PubMed

Neira-Peña, T; Rojas-Mancilla, E; Munoz-Vio, V; Perez, R; Gutierrez-Hernandez, M; Bustamante, D; Morales, P; Hermoso, M A; Gebicke-Haerter, P; Herrera-Marschitz, M

2015-05-01

Perinatal asphyxia (PA) is a leading cause of neuronal damage in newborns, resulting in long-term neurological and cognitive deficits, in part due to impairment of mesostriatal and mesolimbic neurocircuitries. The insult can be as severe as to menace the integrity of the genome, triggering the overactivation of sentinel proteins, including poly (ADP-ribose) polymerase-1 (PARP-1). PARP-1 overactivation implies increased energy demands, worsening the metabolic failure and depleting further NAD(+) availability. Using a global PA rat model, we report here evidence that hypoxia increases PARP-1 activity, triggering a signalling cascade leading to nuclear translocation of the NF-κB subunit p65, modulating the expression of IL-1β and TNF-α, pro-inflammatory molecules, increasing apoptotic-like cell death in mesencephalon of neonate rats, monitored with Western blots, qPCR, TUNEL and ELISA. PARP-1 activity increased immediately after PA, reaching a maximum 1-8 h after the insult, while activation of the NF-κB signalling pathway was observed 8 h after the insult, with a >twofold increase of p65 nuclear translocation. IL-1β and TNF-α mRNA levels were increased 24 h after the insult, together with a >twofold increase in apoptotic-like cell death. A single dose of the PARP-1 inhibitor nicotinamide (0.8 mmol/kg, i.p.), 1 h post delivery, prevented the effect of PA on PARP-1 activity, p65 translocation, pro-inflammatory cytokine expression and apoptotic-like cell death. The present study demonstrates that PA leads to PARP-1 overactivation, increasing the expression of pro-inflammatory cytokines and cell death in mesencephalon, effects prevented by systemic neonatal nicotinamide administration, supporting the idea that PARP-1 inhibition represents a therapeutic target against the effects of PA.

Attenuation of oxidative stress and cardioprotective effects of zinc supplementation in experimental diabetic rats.

PubMed

Barman, Susmita; Srinivasan, Krishnapura

2017-02-01

Oxidative stress plays a major role in the pathogenesis of diabetes mellitus, which further exacerbates damage of cardiac, hepatic and other tissues. We have recently reported that Zn supplementation beneficially modulates hyperglycaemia and hypoinsulinaemia, with attendant reduction of associated metabolic abnormalities in diabetic rats. The present study assessed the potential of Zn supplementation in modulating oxidative stress and cardioprotective effects in diabetic rats. Diabetes was induced in Wistar rats with streptozotocin, and groups of diabetic rats were treated with 5- and 10-fold dietary Zn interventions (0·19 and 0·38 g Zn/kg diet) for 6 weeks. The markers of oxidative stress, antioxidant enzyme activities and concentrations of antioxidant molecules, lipid profile, and expressions of fibrosis and pro-apoptotic factors in the cardiac tissue were particularly assessed. Supplemental Zn showed significant attenuation of diabetes-induced oxidative stress in terms of altered antioxidant enzyme activities and increased the concentrations of antioxidant molecules. Hypercholesterolaemia and hyperlipidaemia were also significantly countered by Zn supplementation. Along with attenuated oxidative stress, Zn supplementation also showed significant cardioprotective effects by altering the mRNA expressions of fibrosis and pro-apoptotic factors (by >50 %). The expression of lipid oxidative marker 4-hydroxy-2-nonenal (4-HNE) protein in cardiac tissue of diabetic animals was rectified (68 %) by Zn supplementation. Elevated cardiac and hepatic markers in circulation and pathological abnormalities in cardiac and hepatic tissue architecture of diabetic animals were ameliorated by dietary Zn intervention. The present study indicates that Zn supplementation can attenuate diabetes-induced oxidative stress in circulation as well as in cardiac and hepatic tissues.

Carbamylated erythropoietin ameliorates the metabolic stress induced in vivo by severe chronic hypoxia

PubMed Central

Fantacci, Monica; Bianciardi, Paola; Caretti, Anna; Coleman, Thomas R.; Cerami, Anthony; Brines, Michael; Samaja, Michele

2006-01-01

Ischemia and chronic hypoxia (CH) trigger a variety of adverse effects arising from metabolic stress that injures cells. In response to reduced O2, hypoxia-inducible factor 1α (HIF-1α) activates erythropoietin (Epo) as well as many other target genes that counteract the effects of O2 deficiency. Epo produced by the kidney stimulates erythrocyte production, leading to decreased HIF-1α production by improved tissue O2 delivery. However, Epo is produced by many other tissues, and it is currently unclear to what extent, if any, locally produced Epo modulates HIF-1α expression. Derivatives of Epo that possess tissue-protective activities but do not stimulate erythropoiesis [e.g., carbamylated Epo (CEpo)] are useful tools with which to determine whether exogenous Epo modulates HIF-1α in the absence of changes in hemoglobin concentration. We compared the effects of CH (6.5% O2 for 10 days) with or without CEpo administered by daily s.c. injection (10 μg/kg of body weight). CEpo administration did not alter the survival rate, weight loss, or increased hemoglobin concentration associated with CH. Therefore, CEpo does not directly suppress HIF-mediated erythropoiesis. CEpo does, however, prevent CH-induced neuronal increases of HIF-1α and Epo receptor-associated immunoreactivity (a measure of stress) while reducing the apoptotic index. In contrast, the myocardium did not exhibit increased HIF-1α expression during CH, although CEpo did reduce the apoptotic index. These observations therefore demonstrate that CEpo administration reduces the metabolic stress caused by severe CH, resulting in improved cellular survival independent of erythrocyte production. PMID:17090665

Aged keratinocyte phenotyping: morphology, biochemical markers and effects of Dead Sea minerals.

PubMed

Soroka, Yoram; Ma'or, Zeev; Leshem, Yael; Verochovsky, Lilian; Neuman, Rami; Brégégère, François Menahem; Milner, Yoram

2008-10-01

The aging process and its characterization in keratinocytes have not been studied in depth until now. We have assessed the cellular and molecular characteristics of aged epidermal keratinocytes in monolayer cultures and in skin by measuring their morphological, fluorometric and biochemical properties. Light and electron microscopy, as well as flow cytometry, revealed increase in cell size, changes in cell shape, alterations in mitochondrial structure and cytoplasmic content with aging. We showed that the expression of 16 biochemical markers was altered in aged cultured cells and in tissues, including caspases 1 and 3 and beta-galactosidase activities, immunoreactivities of p16, Ki67, 20S proteasome and effectors of the Fas-dependent apoptotic pathway. Aged cells diversity, and individual variability of aging markers, call for a multifunctional assessment of the aging phenomenon, and of its modulation by drugs. As a test case, we have measured the effects of Dead Sea minerals on keratinocyte cultures and human skin, and found that they stimulate proliferation and mitochondrial activity, decrease the expression of some aging markers, and limit apoptotic damage after UVB irradiation.

Dynamical states, possibilities and propagation of stress signal

PubMed Central

Malik, Md. Zubbair; Ali, Shahnawaz; Singh, Soibam Shyamchand; Ishrat, Romana; Singh, R. K. Brojen

2017-01-01

The stress driven dynamics of Notch-Wnt-p53 cross-talk is subjected to a few possible dynamical states governed by simple fractal rules, and allowed to decide its own fate by choosing one of these states which are contributed from long range correlation with varied fluctuations due to active molecular interaction. The topological properties of the networks corresponding to these dynamical states have hierarchical features with assortive structure. The stress signal driven by nutlin and modulated by mediator GSK3 acts as anti-apoptotic signal in this system, whereas, the stress signal driven by Axin and modulated by GSK3 behaves as anti-apoptotic for a certain range of Axin and GSK3 interaction, and beyond which the signal acts as favor-apoptotic signal. However, this stress system prefers to stay in an active dynamical state whose counterpart complex network is closest to hierarchical topology with exhibited roles of few interacting hubs. During the propagation of stress signal, the system allows the propagator pathway to inherit all possible properties of the state to the receiver pathway/pathways with slight modifications, indicating efficient information processing and democratic sharing of responsibilities in the system via cross-talk. The increase in the number of cross-talk pathways in the system favors to establish self-organization. PMID:28106087

EGCG protects against homocysteine-induced human umbilical vein endothelial cells apoptosis by modulating mitochondrial-dependent apoptotic signaling and PI3K/Akt/eNOS signaling pathways.

PubMed

Liu, Shumin; Sun, Zhengwu; Chu, Peng; Li, Hailong; Ahsan, Anil; Zhou, Ziru; Zhang, Zonghui; Sun, Bin; Wu, Jingjun; Xi, Yalin; Han, Guozhu; Lin, Yuan; Peng, Jinyong; Tang, Zeyao

2017-05-01

Homocysteine (Hcy) induced vascular endothelial injury leads to the progression of endothelial dysfunction in atherosclerosis. Epigallocatechin gallate (EGCG), a natural dietary antioxidant, has been applied to protect against atherosclerosis. However, the underlying protective mechanism of EGCG has not been clarified. The present study investigated the mechanism of EGCG protected against Hcy-induced human umbilical vein endothelial cells (HUVECs) apoptosis. Methyl thiazolyl tetrazolium assay (MTT), transmission electron microscope, fluorescent staining, flow cytometry, western blot were used in this study. The study has demonstrated that EGCG suppressed Hcy-induced endothelial cell morphological changes and reactive oxygen species (ROS) generation. Moreover, EGCG dose-dependently prevented Hcy-induced HUVECs cytotoxicity and apoptotic biochemical changes such as reducing mitochondrial membrane potential (MMP), decreasing Bcl-2/Bax protein ratio and activating caspase-9 and 3. In addition, EGCG enhanced the protein ratio of p-Akt/Akt, endothelial nitric oxide synthase (eNOS) activation and nitric oxide (NO) formation in injured cells. In conclusion, the present study shows that EGCG prevents Hcy-induced HUVECs apoptosis via modulating mitochondrial apoptotic and PI3K/Akt/eNOS signaling pathways. Furthermore, the results indicate that EGCG is likely to represent a potential therapeutic strategy for atherosclerosis associated with Hyperhomocysteinemia (HHcy).

Dynamical states, possibilities and propagation of stress signal.

PubMed

Malik, Md Zubbair; Ali, Shahnawaz; Singh, Soibam Shyamchand; Ishrat, Romana; Singh, R K Brojen

2017-01-20

The stress driven dynamics of Notch-Wnt-p53 cross-talk is subjected to a few possible dynamical states governed by simple fractal rules, and allowed to decide its own fate by choosing one of these states which are contributed from long range correlation with varied fluctuations due to active molecular interaction. The topological properties of the networks corresponding to these dynamical states have hierarchical features with assortive structure. The stress signal driven by nutlin and modulated by mediator GSK3 acts as anti-apoptotic signal in this system, whereas, the stress signal driven by Axin and modulated by GSK3 behaves as anti-apoptotic for a certain range of Axin and GSK3 interaction, and beyond which the signal acts as favor-apoptotic signal. However, this stress system prefers to stay in an active dynamical state whose counterpart complex network is closest to hierarchical topology with exhibited roles of few interacting hubs. During the propagation of stress signal, the system allows the propagator pathway to inherit all possible properties of the state to the receiver pathway/pathways with slight modifications, indicating efficient information processing and democratic sharing of responsibilities in the system via cross-talk. The increase in the number of cross-talk pathways in the system favors to establish self-organization.

Docosahexaenoic acid: brain accretion and roles in neuroprotection after brain hypoxia and ischemia

PubMed Central

Mayurasakorn, Korapat; Williams, Jill J.; Ten, Vadim S.; Deckelbaum, Richard J.

2014-01-01

Purpose of review With important effects on neuronal lipid composition, neurochemical signaling and cerebrovascular pathobiology, docosahexaenoic acid (DHA), a n-3 polyunsaturated fatty acid, may emerge as a neuroprotective agent against cerebrovascular disease. This paper examines pathways for DHA accretion in brain and evidence for possible roles of DHA in prophylactic and therapeutic approaches for cerebrovascular disease. Recent findings DHA is a major n-3 fatty acid in the mammalian central nervous system and enhances synaptic activities in neuronal cells. DHA can be obtained through diet or to a limited extent via conversion from its precursor, α-linolenic acid (α-LNA). DHA attenuates brain necrosis after hypoxic ischemic injury, principally by modulating membrane biophysical properties and maintaining integrity in functions between pre-and post-synaptic areas, resulting in better stabilizing intracellular ion balance in hypoxic-ischemic insult. Additionally, DHA alleviates brain apoptosis, by inducing anti-apoptotic activities such as decreasing responses to reactive oxygen species, up-regulating anti-apoptotic protein expression, down-regulating apoptotic protein expression, and maintaining mitochondrial integrity and function. Summary DHA in brain relates to a number of efficient delivery and accretion pathways. In animal models DHA renders neuroprotection after hypoxic-ischemic injury by regulating multiple molecular pathways and gene expression. PMID:21178607

[6]-Shogaol, a dietary phenolic compound, induces oxidative stress mediated mitochondrial dependant apoptosis through activation of proapoptotic factors in Hep-2 cells.

PubMed

Annamalai, Govindhan; Kathiresan, Suresh; Kannappan, Nagappan

2016-08-01

Ginger (Zingiber officinale) is a well-known herb used in ethnomedicine. [6]-shogaol, a phenolic nature is a major constituent of ginger. In this study, we investigated the anticancer activity of [6]-shogaol in Laryngeal cancer (Hep-2) cells. We demonstrated the effects of [6]-shogaol on the cell growth and apoptosis in Hep-2 cells were analyzed by the generation of reactive oxygen species (ROS), the level of mitochondrial membrane potential (ΔYm), DNA damage and apoptotic morphological changes were analyzed by AO/EtBr, AO and Hoechst staining. Further, apoptotic protein expressions were analyzed by western blot analysis. Our results indicated that [6]-shogaol induces apoptosis as evidenced by loss of cell viability, enhanced ROS, lipid peroxidation results in altered mitochondrial membrane potential, increased DNA damage in Hep-2 cells. Further, the prooxidant role of [6]-shogaol inhibit Bcl-2 expression with the simultaneous up-regulation of Bax, Cytochrome c, Caspase-9 and -3 protein expressions were observed in Hep-2 cells. Thus, [6]-shogaol induces apoptosis in Hep-2 cells through inducing oxidative damage and modulate apoptotic marker expressions. Therefore, [6]-shogaol might be used as a therapeutic agent for the treatment of laryngeal cancer. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Cardioprotection Via Modulation of Calcium Homeostasis by Thiopental in Hypoxia-Reoxygenated Neonatal Rat Cardiomyocytes

PubMed Central

Kim, Hyun-Soo; Hwang, Ki-Chul

2010-01-01

Purpose Ca2+ homeostasis plays an important role in myocardial cell injury induced by hypoxia-reoxygenation, and prevention of intracellular Ca2+ overload is key to cardioprotection. Even though thiopental is a frequently used anesthetic agent, little is known about its cardioprotective effects, particulary in association with Ca2+ homeostasis. We investigated whether thiopental protects cardiomyocytes against hypoxia-reoxygenation injury by regulating Ca2+ homeostasis. Materials and Methods Neonatal rat cardiomyocytes were isolated. Cardiomyocytes were exposed to different concentrations of thiopental and immediately replaced in the hypoxic chamber to maintain hypoxia. After 1 hour of exposure, a culture dish was transferred to the CO2 incubator and cells were incubated at 37℃ for 5 hours. At the end of the experiments, the authors assessed cell protection using immunoblot analysis and caspase activity. The mRNA of genes involved in Ca2+ homeostasis, mitochondrial membrane potential, and cellular Ca2+ levels were examined. Results In thiopental-treated cardiomyocytes, there was a decrease in expression of the proapoptotic protein Bax, caspase-3 activation, and intracellular Ca2+ content. In addition, both enhancement of anti-apoptotic protein Bcl-2 and activation of Erk concerned with survival were shown. Furthermore, thiopental attenuated alterations of genes involving Ca2+ regulation and significantly modulated abnormal changes of NCX and SERCA2a genes in hypoxia-reoxygenated neonatal cardiomyocytes. Thiopental suppressed disruption of mitochondrial membrane potential (ΔΨm) induced by hypoxia-reoxygenation. Conclusion Thiopental is likely to modulate expression of genes that regulate Ca2+ homeostasis, which reduces apoptotic cell death and results in cardioprotection. PMID:20191008

SPATA4 Counteracts Etoposide-Induced Apoptosis via Modulating Bcl-2 Family Proteins in HeLa Cells.

PubMed

Jiang, Junjun; Li, Liyuan; Xie, Mingchao; Fuji, Ryosuke; Liu, Shangfeng; Yin, Xiaobei; Li, Genlin; Wang, Zhao

2015-01-01

Spermatogenesis associated 4 (SPATA4) is a testis-specific gene first cloned by our laboratory, and plays an important role in maintaining the physiological function of germ cells. Accumulated evidence suggests that SPATA4 might be associated with apoptosis. Here we established HeLa cells that stably expressed SPATA4 to investigate the function of SPATA4 in apoptosis. SPATA4 protected HeLa cells from etoposide-induced apoptosis through the mitochondrial apoptotic pathway, in the way that SPATA4 suppressed decrease of the mitochondrial membrane potential, the release of cytochrome c, and subsequent activation of caspase-9 and -3. We further demonstrated that SPATA4 upregulated anti-apoptotic members of Bcl-2 family proteins, Bcl-2, and downregulated the pro-apoptotic member of Bcl-2 family proteins, Bax. Knockdown of SPATA4 in HeLa/SPATA4 cells could partially rescue expression levels of bcl-2 and bax. In conclusion, SPATA4 protects HeLa cells against etoposide-induced apoptosis through the mitochondrial apoptotic pathway. Our findings provide further evidence that SPATA4 plays a role in regulating apoptosis.

Menadione (Vitamin K3) induces apoptosis of human oral cancer cells and reduces their metastatic potential by modulating the expression of epithelial to mesenchymal transition markers and inhibiting migration.

PubMed

Suresh, Shruthy; Raghu, Dinesh; Karunagaran, Devarajan

2013-01-01

Oral cancer is one of the most commonly occurring cancers worldwide, decreasing the patient's survival rate due to tumor recurrence and metastasis. Menadione (Vitamin K3) is known to exhibit cytotoxicity in various cancer cells but the present study focused on its effects on viability, apoptosis, epithelial to mesenchymal transition (EMT), anchorage independent growth and migration of oral cancer cells. The results show that menadione is more cytotoxic to SAS (oral squamous carcinoma) cells but not to non-tumorigenic HEK293 and HaCaT cells. Menadione treatment increased the expression of pro-apoptotic proteins, Bax and p53, with a concurrent decrease in anti-apoptotic proteins, Bcl-2 and p65. Menadione induced the expression of E-cadherin but reduced the expression of EMT markers, vimentin and fibronectin. Menadione also inhibited anchorage independent growth and migration in SAS cells. These findings reveal and confirm that menadione is a potential candidate in oral cancer therapy as it exhibits cytotoxic, antineoplastic and antimigratory effects besides effectively blocking EMT in oral cancer cells.

Multi-Modal Strategies for Overcoming Tumor Drug Resistance: Hypoxia, Warburg’s Effect, Stem Cells, and Multifunctional Nanotechnology

PubMed Central

Milane, Lara; Ganesh, Shanthi; Shah, Shruti; Duan, Zhen-feng; Amiji, Mansoor

2011-01-01

Inefficiency in systemic drug delivery and tumor residence as well microenvironmental selection pressures contribute to the development of multidrug resistance (MDR) in cancer. Characteristics of MDR include abnormal vasculature, regions of hypoxia, up-regulation of ABC-transporters, aerobic glycolysis, and an elevated apoptotic threshold. Nano-sized delivery vehicles are ideal for treating MDR cancer as they can improve the therapeutic index of drugs and they can be engineered to achieve multifunctional parameters. The multifunctional ability of nanocarriers makes them more adept at treating heterogeneous tumor mass than traditional chemotherapy. Nanocarriers also have preferential tumor accumulation via the EPR effect; this accumulation can be further enhanced by actively targeting the biological profile of MDR cells. Perhaps the most significant benefit of using nanocarrier drug delivery to treat MDR cancer is that nanocarrier delivery diverts the effects of ABC-transporter mediated drug efflux; which is the primary mechanism of MDR. This review discusses the capabilities, applications, and examples of multifunctional nanocarriers for the treatment of MDR. This review emphasizes multifunctional nanocarriers that enhance drug delivery efficiency, the application of RNAi, modulation of the tumor apoptotic threshold, and physical approaches to overcome MDR. PMID:21497176

Selenium nanoparticles involve HSP-70 and SIRT1 in preventing the progression of type 1 diabetic nephropathy.

PubMed

Kumar, Goru Santosh; Kulkarni, Apoorva; Khurana, Amit; Kaur, Jasmine; Tikoo, Kulbhushan

2014-11-05

The present study was undertaken to examine the protective effect of selenium nanoparticles (SeNPs) in the progression of diabetic nephropathy (DN). Diabetes was induced in male Sprague Dawley (SD) rats by injecting streptozotocin (STZ) (55mg/kg, i.p). DN was then assessed by measuring blood urea nitrogen (BUN), creatinine, albumin, fibronectin and collagen. Changes in the expression of cytoprotective and apoptotic proteins in the kidney of rats were also examined. Herein we show that SeNPs effectively lowered the levels of BUN, creatinine, fibronectin and collagen and elevated the levels of albumin in diabetic rats. Histological observation corroborated with the above protective effects of SeNPs. Interestingly, SeNPs elevated the levels of heat shock protein (HSP-70), longevity protein SIRT 1 and also modulated apoptotic proteins Bax and Bcl-2 in diabetic kidney. Our data represents a paradigm shift in our understanding about the therapeutic potential of SeNPs in preventing DN by not only quenching oxidative stress but also by activating cyto-protective protein HSP70 and longevity protein SIRT1. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Involvement of PI3K/Akt, ERK and p38 signaling pathways in emodin-mediated extrinsic and intrinsic human hepatoblastoma cell apoptosis.

PubMed

Cui, Yuting; Lu, Peiran; Song, Ge; Liu, Qian; Zhu, Di; Liu, Xuebo

2016-06-01

As a natural anthraquinone derivative, 1,3,8-trihydroxy-6-methylanthraquinone, known as emodin, has recently been reported to possess potential chemopreventive capacity, but the underlying molecular mechanism of its hepatocyte toxicity remains poorly clarified. The present research indicated that emodin targeted HepG2 cells without being cytotoxic to primary human hepatocyte cells in comparison with chrysophanol and rhein. The anti-proliferative effect of emodin was ascribed to occurrence of apoptosis, which characterized by higher ethidium bromide signal, brighter DAPI fluorescence, cleavages of procaspase-3 and poly (ADP-ribose) polymerase as well as quantitative result from Annexin V-FITC/PI double staining. Furthermore, emodin improved Bax/Bcl-2 ratio, elicited disruption of mitochondrial membrane potential and promoted efflux of cytochrome c to cytosol, indicative of features of mitochondria-dependent apoptotic signals. Emodin concurrently led to activations of Fas, Fas-L, caspase-8 and tBid, which provoked death receptor apoptotic signals. Notably, activated tBid relayed the Fas apoptotic signal to the mitochondrial pathway. Besides, emodin effectively attenuated phosphorylations of Akt and ERK and promoted phosphorylation of p38. Inhibitions of PI3K/Akt and ERK and activation of p38 mediated emodin-induced apoptosis through modulating the mitochondrial pathway and/or death receptor pathway. Additionally, there was a cross-talk between PI3K/Akt and MAPKs pathways in emodin-induced apoptosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antigenotoxic and Apoptotic Activity of Green Tea Polyphenol Extracts on Hexavalent Chromium-Induced DNA Damage in Peripheral Blood of CD-1 Mice: Analysis with Differential Acridine Orange/Ethidium Bromide Staining

PubMed Central

García-Rodríguez, María del Carmen; Carvente-Juárez, Megumi Monserrat; Altamirano-Lozano, Mario Agustín

2013-01-01

This study was conducted to investigate the modulating effects of green tea polyphenols on genotoxic damage and apoptotic activity induced by hexavalent chromium [Cr (VI)] in CD-1 mice. Animals were divided into the following groups: (i) injected with vehicle; (ii) treated with green tea polyphenols (30 mg/kg) via gavage; (iii) injected with CrO3 (20 mg/kg) intraperitoneally; (iv) treated with green tea polyphenols in addition to CrO3. Genotoxic damage was evaluated by examining micronucleated polychromatic erythrocytes (MN-PCEs) obtained from peripheral blood at 0, 24, 48, and 72 h after treatment. Induction of apoptosis and cell viability were assessed by differential acridine orange/ethidium bromide (AO/EB) staining. Treatment of green tea polyphenols led to no significant changes in the MN-PCEs. However, CrO3 treatment significantly increased MN-PCEs at 24 and 48 h after injection. Green tea polyphenols treatment prior to CrO3 injection led to a decrease in MN-PCEs compared to the group treated with CrO3 only. The average of apoptotic cells was increased at 48 h after treatment compared to control mice, suggesting that apoptosis could contribute to eliminate the DNA damaged cells induced by Cr (VI). Our findings support the proposed protective effects of green tea polyphenols against the genotoxic damage induced by Cr (VI). PMID:24363823

A genetic variant of the anti-apoptotic protein Akt predicts natalizumab-induced lymphocytosis and post-natalizumab multiple sclerosis reactivation.

PubMed

Rossi, Silvia; Motta, Caterina; Studer, Valeria; Monteleone, Fabrizia; De Chiara, Valentina; Buttari, Fabio; Barbieri, Francesca; Bernardi, Giorgio; Battistini, Luca; Cutter, Gary; Stüve, Olaf; Salvetti, Marco; Centonze, Diego

2013-01-01

Multiple sclerosis (MS) patients discontinuing natalizumab treatment are at risk of disease reactivation. No clinical or surrogate parameters exist to identify patients at risk of post-natalizumab MS reactivation. To determine the role of natalizumab-induced lymphocytosis and of Akt polymorphisms in disease reactivation after natalizumab discontinuation. Peripheral leukocyte count and composition were monitored in 93 MS patients during natalizumab treatment, and in 56 of these subjects who discontinued the treatment. Genetic variants of the anti-apoptotic protein Akt were determined in all subjects because natalizumab modulates the apoptotic pathway and lymphocyte survival is regulated by the apoptotic cascade. Natalizumab-induced peripheral lymphocytosis protected from post-natalizumab MS reactivation. Subjects who relapsed or had magnetic resonance imaging (MRI) worsening after treatment cessation, in fact, had milder peripheral lymphocyte increases during the treatment, largely caused by less marked T cell increase. Furthermore, subjects carrying a variant of the gene coding for Akt associated with reduced anti-apoptotic efficiency (rs2498804T) had lower lymphocytosis and higher risk of disease reactivation. This study identified one functionally meaningful genetic variant within the Akt signaling pathway that is associated with both lymphocyte count and composition alterations during natalizumab treatment, and with the risk of disease reactivation after natalizumab discontinuation.

Parental exposure to natural mixtures of persistent organic pollutants (POP) induced changes in transcription of apoptosis-related genes in offspring zebrafish embryos.

PubMed

Lyche, Jan L; Grześ, Irena M; Karlsson, Camilla; Nourizadeh-Lillabadi, Rasoul; Aleström, Peter; Ropstad, Erik

2016-01-01

Apoptosis is an integral element of development that may also be initiated by environmental contaminants. The aim of the present study was to assess potential changes in the regulation of apoptotic genes in zebrafish embryos following parental exposure to two natural mixtures of persistent organic pollutants (POP). The mixture from Lake Mjøsa contained exceptionally high concentrations of polybrominated diphenyl ethers (PBDE), as well as relatively high levels of polychlorinated biphenyls (PCB) and dichlorodiphenyltrichloroethane (DDT). The mixture from Lake Losna contained background concentrations of POP. Genes involved in the apoptotic machinery were screened for their expression profile at four time points during embryonic development. Thirteen and 15 genes involved in apoptosis were found to be significantly upregulated in the high-exposure and background exposure groups, respectively, compared with controls. Modulation of apoptotic genes was restricted only to the first time point, which corresponds with the blastula stage. Although there were substantial differences in POP concentrations between mixtures, genes underlying the apoptosis process showed almost similar responses to the two mixtures. In both exposure groups the main executors of apoptosis p53, casp 2, casp 6, cassp 8, and BAX displayed upregulation compared to controls, suggesting that these POP induce apoptosis via a p53-dependent mechanism. Upregulation of genes that play a critical role in apoptosis suggests that disturbance of normal apoptotic signaling during gametogenesis and embryogenesis may be one of the central mechanisms involved in adverse reproductive effects produced by POP in zebrafish.

St. John's wort extract and hyperforin inhibit multiple phosphorylation steps of cytokine signaling and prevent inflammatory and apoptotic gene induction in pancreatic β cells.

PubMed

Novelli, Michela; Menegazzi, Marta; Beffy, Pascale; Porozov, Svetlana; Gregorelli, Alex; Giacopelli, Daniela; De Tata, Vincenzo; Masiello, Pellegrino

2016-12-01

The extract of the herbaceous plant St. John's wort (SJW) and its phloroglucinol component hyperforin (HPF) were previously shown to inhibit cytokine-induced STAT-1 and NF-κB activation and prevent damage in pancreatic β cells. To further clarify the mechanisms underlying their protective effects, we evaluated the phosphorylation state of various factors of cytokine signaling pathways and the expression of target genes involved in β-cell function, inflammatory response and apoptosis induction. In the INS-1E β-cell line, exposed to a cytokine mixture with/without SJW extract (2-5μg/ml) or HPF (1-5μM), protein phosphorylation was assessed by western blotting and expression of target genes by real-time quantitative PCR. SJW and HPF markedly inhibited, in a dose-dependent manner (from 60 to 100%), cytokine-induced activating phosphorylations of STAT-1, NF-κB p65 subunit and IKK (NF-κB inhibitory subunit IκBα kinase). MAPK and Akt pathways were also modulated by the vegetal compounds through hindrance of p38 MAPK, ERK1/2, JNK and Akt phosphorylations, each reduced by at least 65% up to 100% at the higher dose. Consistently, SJW and HPF a) abolished cytokine-induced mRNA expression of pro-inflammatory genes; b) avoided down-regulation of relevant β-cell functional/differentiation genes; c) corrected cytokine-driven imbalance between pro- and anti-apoptotic factors, by fully preventing up-regulation of pro-apoptotic genes and preserving expression or function of anti-apoptotic Bcl-2 family members; d) protected INS-1E cells against cytokine-induced apoptosis. In conclusion, SJW extract and HPF exert their protective effects through simultaneous inhibition of multiple phosphorylation steps along various cytokine signaling pathways and consequent restriction of inflammatory and apoptotic gene expression. Thus, they have a promising therapeutic potential for the prevention or limitation of immune-mediated β-cell dysfunction and damage leading to type 1 diabetes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Matrix metalloproteinase-9 is involved in chronic lymphocytic leukemia cell response to fludarabine and arsenic trioxide.

PubMed

Amigo-Jiménez, Irene; Bailón, Elvira; Ugarte-Berzal, Estefanía; Aguilera-Montilla, Noemí; García-Marco, José A; García-Pardo, Angeles

2014-01-01

Matrix metalloproteinase-9 (MMP-9) contributes to chronic lymphocytic leukemia (CLL) pathology by regulating cell migration and preventing spontaneous apoptosis. It is not known if MMP-9 is involved in CLL cell response to chemotherapy and we address this in the present study, using arsenic trioxide (ATO) and fludarabine as examples of cytotoxic drugs. We used primary cells from the peripheral blood of CLL patients and MEC-1 cells stably transfected with an empty vector or a vector containing MMP-9. The effect of ATO and fludarabine was determined by flow cytometry and by the MTT assay. Expression of mRNA was measured by RT-PCR and qPCR. Secreted and cell-bound MMP-9 was analyzed by gelatin zymography and flow cytometry, respectively. Protein expression was analyzed by Western blotting and immunoprecipitation. Statistical analyses were performed using the two-tailed Student's t-test. In response to ATO or fludarabine, CLL cells transcriptionally upregulated MMP-9, preceding the onset of apoptosis. Upregulated MMP-9 primarily localized to the membrane of early apoptotic cells and blocking apoptosis with Z-VAD prevented MMP-9 upregulation, thus linking MMP-9 to the apoptotic process. Culturing CLL cells on MMP-9 or stromal cells induced drug resistance, which was overcome by anti-MMP-9 antibodies. Accordingly, MMP-9-MEC-1 transfectants showed higher viability upon drug treatment than Mock-MEC-1 cells, and this effect was blocked by silencing MMP-9 with specific siRNAs. Following drug exposure, expression of anti-apoptotic proteins (Mcl-1, Bcl-xL, Bcl-2) and the Mcl-1/Bim, Mcl-1/Noxa, Bcl-2/Bax ratios were higher in MMP-9-cells than in Mock-cells. Similar results were obtained upon culturing primary CLL cells on MMP-9. Our study describes for the first time that MMP-9 induces drug resistance by modulating proteins of the Bcl-2 family and upregulating the corresponding anti-apoptotic/pro-apoptotic ratios. This is a novel role for MMP-9 contributing to CLL progression. Targeting MMP-9 in combined therapies may thus improve CLL response to treatment.

Matrix Metalloproteinase-9 Is Involved in Chronic Lymphocytic Leukemia Cell Response to Fludarabine and Arsenic Trioxide

PubMed Central

Amigo-Jiménez, Irene; Bailón, Elvira; Ugarte-Berzal, Estefanía; Aguilera-Montilla, Noemí; García-Marco, José A.; García-Pardo, Angeles

2014-01-01

Background Matrix metalloproteinase-9 (MMP-9) contributes to chronic lymphocytic leukemia (CLL) pathology by regulating cell migration and preventing spontaneous apoptosis. It is not known if MMP-9 is involved in CLL cell response to chemotherapy and we address this in the present study, using arsenic trioxide (ATO) and fludarabine as examples of cytotoxic drugs. Methods We used primary cells from the peripheral blood of CLL patients and MEC-1 cells stably transfected with an empty vector or a vector containing MMP-9. The effect of ATO and fludarabine was determined by flow cytometry and by the MTT assay. Expression of mRNA was measured by RT-PCR and qPCR. Secreted and cell-bound MMP-9 was analyzed by gelatin zymography and flow cytometry, respectively. Protein expression was analyzed by Western blotting and immunoprecipitation. Statistical analyses were performed using the two-tailed Student's t-test. Results In response to ATO or fludarabine, CLL cells transcriptionally upregulated MMP-9, preceding the onset of apoptosis. Upregulated MMP-9 primarily localized to the membrane of early apoptotic cells and blocking apoptosis with Z-VAD prevented MMP-9 upregulation, thus linking MMP-9 to the apoptotic process. Culturing CLL cells on MMP-9 or stromal cells induced drug resistance, which was overcome by anti-MMP-9 antibodies. Accordingly, MMP-9-MEC-1 transfectants showed higher viability upon drug treatment than Mock-MEC-1 cells, and this effect was blocked by silencing MMP-9 with specific siRNAs. Following drug exposure, expression of anti-apoptotic proteins (Mcl-1, Bcl-xL, Bcl-2) and the Mcl-1/Bim, Mcl-1/Noxa, Bcl-2/Bax ratios were higher in MMP-9-cells than in Mock-cells. Similar results were obtained upon culturing primary CLL cells on MMP-9. Conclusions Our study describes for the first time that MMP-9 induces drug resistance by modulating proteins of the Bcl-2 family and upregulating the corresponding anti-apoptotic/pro-apoptotic ratios. This is a novel role for MMP-9 contributing to CLL progression. Targeting MMP-9 in combined therapies may thus improve CLL response to treatment. PMID:24956101

Evaluation of heterocyclic steroids and curcumin derivatives as anti-breast cancer agents: Studying the effect on apoptosis in MCF-7 breast cancer cells.

PubMed

Elmegeed, Gamal A; Yahya, Shaymaa M M; Abd-Elhalim, Mervat M; Mohamed, Mervat S; Mohareb, Rafat M; Elsayed, Ghada H

2016-11-01

Anticancer agents consisting of hybrid molecules are used to improve effectiveness and diminish drug resistance. The current study aimed to introduce newly synthesized hetero-steroids of promising anticancer effects. Besides, the pro-apoptotic effects of new compounds were investigated extensively. Several pyrimidino-, triazolopyrimidino-, pyridazino-, and curcumin-steroid derivatives were synthesized, elucidated and confirmed using the spectral and analytical data. The synthesized hetero-steroids, compounds 9, 10, 11, 12, 13, 14, 15, 18, 20, 21, 22 and 24, were tested for their cytotoxic effects versus human breast cancer cells (MCF-7) using neutral red supravital dye uptake assay. Compound 24 (IC50=18μM) showed more inhibitory influence on MCF-7 growth. Using QRT-PCR (Quantitative real time-polymerase chain reaction), CCND1, Survivin, BCL-2, CDC2, P21 and P53, genes expression levels were investigated. The study results disclose that compounds 4, 7, 18, 24 knocked down the expression levels of CCND1, Survivin, BCL-2 and CDC2. However, P21 and P53 were up-regulated by compounds 21, 22. This study introduced promising pro-apoptotic anticancer agents acting through the modulation of key regulators of apoptosis and cell cycle genes. Copyright © 2016 Elsevier Inc. All rights reserved.

Protein C Inhibitor (PCI) Binds to Phosphatidylserine Exposing Cells with Implications in the Phagocytosis of Apoptotic Cells and Activated Platelets

PubMed Central

Rieger, Daniela; Assinger, Alice; Einfinger, Katrin; Sokolikova, Barbora; Geiger, Margarethe

2014-01-01

Protein C Inhibitor (PCI) is a secreted serine protease inhibitor, belonging to the family of serpins. In addition to activated protein C PCI inactivates several other proteases of the coagulation and fibrinolytic systems, suggesting a regulatory role in hemostasis. Glycosaminoglycans and certain negatively charged phospholipids, like phosphatidylserine, bind to PCI and modulate its activity. Phosphatidylerine (PS) is exposed on the surface of apoptotic cells and known as a phagocytosis marker. We hypothesized that PCI might bind to PS exposed on apoptotic cells and thereby influence their removal by phagocytosis. Using Jurkat T-lymphocytes and U937 myeloid cells, we show here that PCI binds to apoptotic cells to a similar extent at the same sites as Annexin V, but in a different manner as compared to live cells (defined spots on ∼10–30% of cells). PCI dose dependently decreased phagocytosis of apoptotic Jurkat cells by U937 macrophages. Moreover, the phagocytosis of PS exposing, activated platelets by human blood derived monocytes declined in the presence of PCI. In U937 cells the expression of PCI as well as the surface binding of PCI increased with time of phorbol ester treatment/macrophage differentiation. The results of this study suggest a role of PCI not only for the function and/or maturation of macrophages, but also as a negative regulator of apoptotic cell and activated platelets removal. PMID:25000564

Persimmon Leaves (Diospyros kaki) Extract Protects Optic Nerve Crush-Induced Retinal Degeneration

PubMed Central

Ryul Ahn, Hong; Kim, Kyung-A; Kang, Suk Woo; Lee, Joo Young; Kim, Tae-Jin; Jung, Sang Hoon

2017-01-01

Retinal ganglion cell (RGC) death is part of many retinal diseases. Here, we report that the ethanol extract of Diospyros kaki (EEDK) exhibits protective properties against retinal degeneration, both in vitro and in vivo. Upon exposure to cytotoxic compounds, RGC-5 cells showed approximately 40% cell viability versus the control, while pre-treatment with EEDK markedly increased cell viability in a concentration-dependent manner. Further studies revealed that cell survival induced by EEDK was associated with decreased levels of apoptotic proteins, such as poly (ADP-ribose) polymerase, p53, and cleaved caspase-3. In addition to apoptotic pathways, we demonstrated that expression levels of antioxidant-associated proteins, such as superoxide dismutase-1, glutathione S-transferase, and glutathione peroxidase-1, were positively modulated by EEDK. In a partial optic nerve crush mouse model, EEDK had similar ameliorating effects on retinal degeneration resulting from mechanical damages. Therefore, our results suggest that EEDK may have therapeutic potential against retinal degenerative disorders, such as glaucoma. PMID:28425487

Anti-ceramidase LCL385 acutely reduces BCL-2 expression in the hippocampus but is not associated with an increase of learned helplessness in rats.

PubMed

Nahas, Ziad; Jiang, Yan; Zeidan, Youssef H; Bielawska, Alicja; Szulc, Zdzislaw; Devane, Lindsay; Kalivas, Peter; Hannun, Yusuf A

2009-01-30

Evidence from in situ studies supports the role of anti-apoptotic factors in the antidepressant responses of certain psychotropics. The availability of anti-ceramidase pro-apoptocic compound (LCL385) provides an opportunity to test in vivo the relation between hippocampal apopotosis and learned helplessness. 40 Sprague-Dawley male rodents underwent an FST after a treatment with LCL385, desipramine (DMI), or placebo (SAL) over 3 days. Behavioral responses, including immobility, swimming and climbing were counted during the 6min test. Western blot labeling was used to detect anti-apoptosis in hippocampus. DMI alone was associated with reduced immobility and increased climbing whereas LCL385 alone showed a decrease in Bcl-2/beta-actin ratio. Direct modulation of Bcl-2 expression in the hippocampus is not associated with learned helplessness in stressed rats. Three-day administration of DMI and LCL385 show divergent effects on behavioral and anti-apoptotic measures.

Manganese activates the mitochondrial apoptotic pathway in rat astrocytes by modulating the expression of proteins of the Bcl-2 family.

PubMed

Gonzalez, Laura E; Juknat, A Ana; Venosa, Andrea J; Verrengia, Noemi; Kotler, Mónica L

2008-12-01

Manganese induces the central nervous system injury leading to manganism, by mechanisms not completely understood. Chronic exposure to manganese generates oxidative stress and induces the mitochondrial permeability transition. In the present study, we characterized apoptotic cell death mechanisms associated with manganese toxicity in rat cortical astrocytes and demonstrated that (i) Mn treatment targets the mitochondria and induces mitochondrial membrane depolarization followed by cytochrome c release to the cytoplasm, (ii) Mn induces both effector caspases 3/7 and 6 as well as PARP-1 cleavage and (iii) Mn shifts the balance of cell death/survival of Bcl-2 family proteins to favor the apoptotic demise of astrocytes. Our model system using cortical rat astrocytes treated with Mn would emerge as a good tool for investigations aimed to elucidate the role of apoptosis in manganism.

A dual role for the anti-apoptotic Bcl-2 protein in cancer: mitochondria versus endoplasmic reticulum.

PubMed

Akl, Haidar; Vervloessem, Tamara; Kiviluoto, Santeri; Bittremieux, Mart; Parys, Jan B; De Smedt, Humbert; Bultynck, Geert

2014-10-01

Anti-apoptotic Bcl-2 contributes to cancer formation and progression by promoting the survival of altered cells. Hence, it is a prime target for novel specific anti-cancer therapeutics. In addition to its canonical anti-apoptotic role, Bcl-2 has an inhibitory effect on cell-cycle progression. Bcl-2 acts at two different intracellular compartments, the mitochondria and the endoplasmic reticulum (ER). At the mitochondria, Bcl-2 via its hydrophobic cleft scaffolds the Bcl-2-homology (BH) domain 3 (BH3) of pro-apoptotic Bcl-2-family members. Small molecules (like BH3 mimetics) can disrupt this interaction, resulting in apoptotic cell death in cancer cells. At the ER, Bcl-2 modulates Ca(2+) signaling, thereby promoting proliferation while increasing resistance to apoptosis. Bcl-2 at the ER acts via its N-terminal BH4 domain, which directly binds and inhibits the inositol 1,4,5-trisphosphate receptor (IP3R), the main intracellular Ca(2+)-release channel. Tools targeting the BH4 domain of Bcl-2 reverse Bcl-2's inhibitory action on IP3Rs and trigger pro-apoptotic Ca(2+) signaling in cancer B-cells, including chronic lymphocytic leukemia (CLL) cells and diffuse large B-cell lymphoma (DLBCL) cells. The sensitivity of DLBCL cells to BH4-domain targeting tools strongly correlated with the expression levels of the IP3R2 channel, the IP3R isoform with the highest affinity for IP3. Interestingly, bio-informatic analysis of a database of primary CLL patient cells also revealed a transcriptional upregulation of IP3R2. Finally, this review proposes a model, in which cancer cell survival depends on Bcl-2 at the mitochondria and/or the ER. This dependence likely will have an impact on their responses to BH3-mimetic drugs and BH4-domain targeting tools. This article is part of a Special Issue entitled: Calcium signaling in health and disease. Guest Editors: Geert Bultynck, Jacques Haiech, Claus W. Heizmann, Joachim Krebs, and Marc Moreau. Copyright © 2014 Elsevier B.V. All rights reserved.

Polyalthia longifolia Methanolic Leaf Extracts (PLME) induce apoptosis, cell cycle arrest and mitochondrial potential depolarization by possibly modulating the redox status in hela cells.

PubMed

Vijayarathna, Soundararajan; Oon, Chern Ein; Chen, Yeng; Kanwar, Jagat R; Sasidharan, Sreenivasan

2017-05-01

Medicinal plants have been accepted as a gold mine, with respect to the diversity of their phytochemicals. Many medicinal plants extracts are potential anticancer agents. Polyalthia longifolia var. angustifolia Thw. (Annonaceae) is one of the most significant native medicinal plants and is found throughout Malaysia. Hence, the present study was intended to assess the anticancer properties of P. longifolia leaf methanolic extract (PLME) and its underlying mechanisms. The Annexin V/PI flow cytometry analysis showed that PLME induces apoptosis in HeLa cells in dose-dependent manner whereas the PI flow cytometric analysis for cell cycle demonstrated the accumulation of cells at sub G0/G1, G0/G1 and G2/M phases. Investigation with JC-1 flow cytometry analysis indicated increase in mitochondria membrane potential depolarisation corresponding to increase in PLME concentrations. PLME was also shown to influence intracellular reactive oxygen species (ROS) by exerting anti-oxidant (half IC 50 ) and pro-oxidant (IC 50 and double IC 50 ) affect against HeLa cells. PLME treatment also displayed DNA damage in HeLa cells in concentration depended fashion. The proteomic profiling array exposed the expression of pro-apoptotic and anti-apoptotic proteins upon PLME treatment at IC 50 concentration in HeLa cells. Pro-apoptotic proteins; BAX, BAD, cytochrome c, caspase-3, p21, p27 and p53 were found to be significantly up-regulated while anti-apoptotic proteins; BCL-2 and BCL-w were found to be significantly down-regulated. This investigation postulated the role of p53 into mediating apoptosis, cell cycle arrest and mitochondrial potential depolarisation by modulating the redox status of HeLa cells. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Two programmed cell death systems in Escherichia coli: an apoptotic-like death is inhibited by the mazEF-mediated death pathway.

PubMed

Erental, Ariel; Sharon, Idith; Engelberg-Kulka, Hanna

2012-01-01

In eukaryotes, the classical form of programmed cell death (PCD) is apoptosis, which has as its specific characteristics DNA fragmentation and membrane depolarization. In Escherichia coli a different PCD system has been reported. It is mediated by the toxin-antitoxin system module mazEF. The E. coli mazEF module is one of the most thoroughly studied toxin-antitoxin systems. mazF encodes a stable toxin, MazF, and mazE encodes a labile antitoxin, MazE, which prevents the lethal effect of MazF. mazEF-mediated cell death is a population phenomenon requiring the quorum-sensing pentapeptide NNWNN designated Extracellular Death Factor (EDF). mazEF is triggered by several stressful conditions, including severe damage to the DNA. Here, using confocal microscopy and FACS analysis, we show that under conditions of severe DNA damage, the triggered mazEF-mediated cell death pathway leads to the inhibition of a second cell death pathway. The latter is an apoptotic-like death (ALD); ALD is mediated by recA and lexA. The mazEF-mediated pathway reduces recA mRNA levels. Based on these results, we offer a molecular model for the maintenance of an altruistic characteristic in cell populations. In our model, the ALD pathway is inhibited by the altruistic EDF-mazEF-mediated death pathway.

Tenascin-C induces resistance to apoptosis in pancreatic cancer cell through activation of ERK/NF-κB pathway.

PubMed

Shi, Meiyan; He, Xiaodan; Wei, Wei; Wang, Juan; Zhang, Ti; Shen, Xiaohong

2015-06-01

As a glycol-protein located in extracellular matrix (ECM), tenascin-C (TNC) is absent in most normal adult tissues but is highly expressed in the majority of malignant solid tumors. Pancreatic cancer is characterized by an abundant fibrous tissue rich in TNC. Although it was reported that TNC's expression increased in the progression from low-grade precursor lesions to invasive cancer and was associated with tumor differentiation in human pancreatic cancer, studies on the relations between TNC and tumor progression in pancreatic cancer were rare. In this study, we performed an analysis to determine the effects of TNC on modulating cell apoptosis and chemo-resistance and explored its mechanisms involving activation in pancreatic cancer cell. The expressions of TNC, ERK1/2/p-ERK1/2, Bcl-xL and Bcl-2 were detected by immunohistochemistry and western blotting. Then the effects of exogenous and endogenous TNC on the regulation of tumor proliferation, apoptosis and gemcitabine cytotoxicity were investigated. The associations among the TNC knockdown, TNC stimulation and expressions of ERK1/2/NF-κB/p65 and apoptotic regulatory proteins were also analyzed in cell lines. The mechanism of TNC on modulating cancer cell apoptosis and drug resistant through activation of ERK1/2/NF-κB/p65 signals was evaluated. The effect of TNC on regulating cell cycle distribution was also tested. TNC, ERK1/2/p-ERK1/2, and apoptotic regulatory proteins Bcl-xL and Bcl-2 were highly expressed in human pancreatic cancer tissues. In vitro, exogenous TNC promoted pancreatic cancer cell growth also mediates basal as well as starved and drug-induced apoptosis in pancreatic cancer cells. The effects of TNC on anti-apoptosis were induced by the activation state of ERK1/2/NF-κB/p65 signals in pancreatic cell. TNC phosphorylate ERK1/2 to induce NF-κB/p65 nucleus translocation. The latter contributes to promote Bcl-xL, Bcl-2 protein expressions and reduce caspase activity, which inhibit cell apoptotic processes. TNC mediated gemcitabine chemo-resistance via modulating cell apoptosis in pancreatic cancer. TNC resulted in the enrichment of pancreatic cancer cells in S-phase with a concomitant decrease in number of cells in G1 phase. The present study indicated TNC in cellular matrix induces an activation of ERK1/2/NF-κB/p65 signaling cascade and thereby mediates resistance to apoptosis in pancreatic cancer. TNC could serve as a diagnostic marker and predictor of gemcitabine response and potentially as a target for chemotherapy of pancreatic cancer.

Apoptotic Effect of Nigella sativa on Human Lymphoma U937 Cells.

PubMed

Arslan, Belkis Atasever; Isik, Fatma Busra; Gur, Hazal; Ozen, Fatih; Catal, Tunc

2017-10-01

Nigella sativa is from botanical Ranunculaceae family and commonly known as black seed. Apoptotic effect of N. sativa and its apoptotic signaling pathways on U937 lymphoma cells are unknown. In this study, we investigated selective cytotoxic and apoptotic effects of N. sativa extract and its apoptotic mechanisms on U937 cells. In addition, we also studied selective cytotoxic activity of thymoquinone that is the most active essential oil of N. sativa . Our results showed that N. sativa extract has selective cytotoxicity and apoptotic effects on U937 cells but not ECV304 control cells. However, thymoquinone had no significant cytotoxicity against on both cells. N. sativa extract increased significantly caspase-3, BAD, and p53 gene expressions in U937 cells. N. sativa may have anticancer drug potential and trigger p53-induced apoptosis in U937 lymphoma cells. This is the first study showing the apoptotic effect of Nigella sativa extract on U937 cells. Abbreviations used: CI: Cytotoxicity index, DMEM: Dulbecco's Modified Eagle Medium, HL: Hodgkin's lymphoma, MTT: 3-(4,5-dimethy lthiazol-2yl)-2,5-diphenyl tetrazolium bromide, RPMI: Roswell Park Memorial Institute medium.

Inhibition of GSK3 differentially modulates NF-{kappa}B, CREB, AP-1 and {beta}-catenin signaling in hepatocytes, but fails to promote TNF-{alpha}-induced apoptosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goetschel, Frank; Kern, Claudia; Lang, Simona

2008-04-01

Glycogen synthase kinase-3 (GSK-3) is known to modulate cell survival and apoptosis through multiple intracellular signaling pathways. However, its hepatoprotective function and its role in activation of NF-{kappa}B and anti-apoptotic factors are poorly understood and remain controversial. Here we investigated whether inhibition of GSK-3 could induce apoptosis in the presence of TNF-{alpha} in primary mouse hepatocytes. We show that pharmacological inhibition of GSK-3 in primary mouse hepatocytes does not lead to TNF-{alpha}-induced apoptosis despite reduced NF-{kappa}B activity. Enhanced stability of I{kappa}B-{alpha} appears to be responsible for lower levels of nuclear NF-{kappa}B and hence reduced transactivation. Additionally, inhibition of GSK-3 wasmore » accompanied by marked upregulation of {beta}-catenin, AP-1, and CREB transcription factors. Stimulation of canonical Wnt signaling and CREB activity led to elevated levels of anti-apoptotic factors. Hence, survival of primary mouse hepatocytes may be caused by the activation and/or upregulation of other key regulators of liver homeostasis and regeneration. These signaling molecules may compensate for the compromised anti-apoptotic function of NF-{kappa}B and allow survival of hepatocytes in the presence of TNF-{alpha} and GSK-3 inhibition.« less

Puerarin protects rat kidney from lead-induced apoptosis by modulating the PI3K/Akt/eNOS pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Chan-Min, E-mail: lcm9009@126.com; Ma, Jie-Qiong; Sun, Yun-Zhi

Puerarin (PU), a natural flavonoid, has been reported to have many benefits and medicinal properties. However, its protective effects against lead (Pb) induced injury in kidney have not been clarified. The aim of the present study was to investigate the effects of puerarin on renal oxidative stress and apoptosis in rats exposed to Pb. Wistar rats were exposed to lead acetate in the drinking water (500 mg Pb/l) with or without puerarin co-administration (100, 200, 300 and 400 mg PU/kg intragastrically once daily) for 75 days. Our data showed that puerarin significantly prevented Pb-induced nephrotoxicity in a dose-dependent manner, indicatedmore » by both diagnostic indicators of kidney damage (serum urea, uric acid and creatinine) and histopathological analysis. Moreover, Pb-induced profound elevation of reactive oxygen species (ROS) production and oxidative stress, as evidenced by increasing of lipid peroxidation level and depleting of intracellular reduced glutathione (GSH) level in kidney, were suppressed by treatment with puerarin. Furthermore, TUNEL assay showed that Pb-induced apoptosis in rat kidney was significantly inhibited by puerarin. In exploring the underlying mechanisms of puerarin action, we found that activities of caspase-3 were markedly inhibited by the treatment of puerarin in the kidney of Pb-treated rats. Puerarin increased phosphorylated Akt, phosphorylated eNOS and NO levels in kidney, which in turn inactivated pro-apoptotic signaling events including inhibition of mitochondria cytochrome c release and restoration of the balance between pro- and anti-apoptotic Bcl-2 proteins in kidney of Pb-treated rats. In conclusion, these results suggested that the inhibition of Pb-induced apoptosis by puerarin is due at least in part to its antioxidant activity and its ability to modulate the PI3K/Akt/eNOS signaling pathway. Highlights: ► Puerarin prevented lead-induced nephrototoxicity. ► Puerarin reduced lead-induced increase in ROS and TBARS production in kidney of rats. ► Puerarin activated the PI3K/Akt/eNOS pathway in kidney. ► Puerarin regulated the expression of pro-apoptotic proteins and caspase activation. ► Puerarin significantly inhibited the lead-induced apoptosis in rat kidney.« less

Changes in proliferating and apoptotic markers of leiomyoma following treatment with a selective progesterone receptor modulator or gonadotropin-releasing hormone agonist.

PubMed

Yun, Bo Seong; Seong, Seok Ju; Cha, Dong Hyun; Kim, Ji Yeon; Kim, Mi-La; Shim, Jeong Yun; Park, Ji Eun

2015-08-01

To evaluate changes in proliferating and apoptotic markers of myoma tissue from patients treated with a selective progesterone receptor modulator (SPRM) or GnRH agonist by measuring expression of PDGF-A mRNA, IGF-1 mRNA, bcl-2 mRNA, and PCNA and caspase-3 protein. Between December 2013 and July 2014, women with symptomatic leiomyoma were divided into control (no treatment before surgery), SPRM (treatment with ulipristal acetate [SPRM] for 3 months before surgery), and GnRHa (treatment with leuprolide acetate [GnRH agonist] for 3 months before surgery) groups. Tissue specimens were collected from the myoma core and normal myometrium of all patients. The expression of mRNA and protein was assessed by quantitative real-time reverse transcriptase-polymerase chain reaction and Western blot. A total of 38 patients were enrolled (control group, n=14; SPRM group, n=13; GnRHa group, n=11). PDGF-A mRNA expression was lower in both the myoma core and normal myometrium tissues of the SPRM compared with the control group, but there was no difference between the control and GnRHa group. There were also no group differences in bcl-2 mRNA or IGF-1 mRNA expression. Both PCNA and caspase-3 protein expression were higher in the leiomyoma tissue of the SPRM compared with the control group, but there was no difference between the control and GnRHa groups in the expression of either protein. Both proliferation and apoptosis were increased in the leiomyoma of patients after SPRM treatment, but there was no change following GnRH agonist treatment, in vivo. However, PDGF-A mRNA was decreased after SPRM treatment, indicating a dual effect of progesterone on the regulation of growth factors. Furthermore, there was an increase in caspase-3 protein, but not bcl-2 mRNA, expression in the SPRM group suggesting that SPRM may exert its effects in pathways other than the bcl-2 apoptotic pathway. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Jeong Eun; Hanyang Biomedical Research Institute, Seoul; Park, Jae Hyeon

Oxidative stress can lead to expression of inflammatory transcription factors, which are important regulatory elements in the induction of inflammatory responses. One of the transcription factors, nuclear transcription factor kappa-B (NF-κB) plays a significant role in the inflammation regulatory process. Inflammatory cell death has been implicated in neuronal cell death in some neurodegenerative disorders such as Parkinson's disease (PD). In this study, we investigated the molecular mechanisms underlying apoptosis initiated by chlorpyrifos (CPF)-mediated oxidative stress. Based on the cytotoxic mechanism of CPF, we examined the neuroprotective effects of rosiglitazone (RGZ), a peroxisome proliferator-activated receptor gamma (PPAR-γ) agonist, against CPF-induced neuronalmore » cell death. The treatment of SH-SY5Y cells with CPF induced oxidative stress. In addition, CPF activated the p38, JNK and ERK mitogen-activated protein kinases (MAPKs), and induced increases in the inflammatory genes such as COX-2 and TNF-α. CPF also induced nuclear translocation of NF-κB and inhibitors of NF-κB abolished the CPF-induced COX-2 expression. Pretreatment with RGZ significantly reduced ROS generation and enhanced HO-1 expression in CPF-exposed cells. RGZ blocked the activation of both p38 and JNK signaling, while ERK activation was strengthened. RGZ also attenuated CPF-induced cell death through the reduction of NF-κB-mediated proinflammatory factors. Results from this study suggest that RGZ may exert an anti-apoptotic effect against CPF-induced cytotoxicity by attenuation of oxidative stress as well as inhibition of the inflammatory cascade via inactivation of signaling by p38 and JNK, and NF-κB. - Highlights: • CPF induces apoptotic cell death in SH-SY5Y cells • ROS involved in CPF-mediated apoptotic cell death • Inflammation involved in CPF-mediated apoptotic cell death • Rosiglitazone modulates ROS and inflammatory response in CPF-treated cells.« less

HIV-1 Tat protein induces glial cell autophagy through enhancement of BAG3 protein levels.

PubMed

Bruno, Anna Paola; De Simone, Francesca Isabella; Iorio, Vittoria; De Marco, Margot; Khalili, Kamel; Sariyer, Ilker Kudret; Capunzo, Mario; Nori, Stefania Lucia; Rosati, Alessandra

2014-01-01

BAG3 protein has been described as an anti-apoptotic and pro-autophagic factor in several neoplastic and normal cells. We previously demonstrated that BAG3 expression is elevated upon HIV-1 infection of glial and T lymphocyte cells. Among HIV-1 proteins, Tat is highly involved in regulating host cell response to viral infection. Therefore, we investigated the possible role of Tat protein in modulating BAG3 protein levels and the autophagic process itself. In this report, we show that transfection with Tat raises BAG3 levels in glioblastoma cells. Moreover, BAG3 silencing results in highly reducing Tat- induced levels of LC3-II and increasing the appearance of sub G0/G1 apoptotic cells, in keeping with the reported role of BAG3 in modulating the autophagy/apoptosis balance. These results demonstrate for the first time that Tat protein is able to stimulate autophagy through increasing BAG3 levels in human glial cells.

Multiple mechanisms modulate distinct cellular susceptibilities towards apoptosis in the developing Drosophila eye

PubMed Central

Fan, Yun; Bergmann, Andreas

2014-01-01

Although apoptosis is mechanistically well understood, a comprehensive understanding of how cells modulate their susceptibility towards apoptosis in a developing tissue is lacking. Here, we reveal striking dynamics in the apoptotic susceptibilities of different cell types in the Drosophila retina over a period of only 24 hours. Mitotic cells are extremely susceptible to apoptotic signals, while post-mitotic cells have developed several strategies to promote survival. For example, photoreceptor neurons accumulate the inhibitor of apoptosis, Diap1. In unspecified cells, Cullin-3-mediated degradation keeps Diap1 levels low. These cells depend on EGFR signaling for survival. As development proceeds, developmentally older photoreceptors degrade Diap1 resulting in increased apoptosis susceptibility. Finally, R8 photoreceptors have very efficient survival mechanisms independently of EGFR or Diap1. These examples illustrate how complex cellular susceptibility towards apoptosis is regulated in a developing organ. Similar complexities may regulate apoptosis susceptibilities in mammalian development and tumor cells may take advantage of it. PMID:24981611

Induction of cell cycle changes and modulation of apoptogenic/anti-apoptotic and extracellular signaling regulatory protein expression by water extracts of I'm-Yunity™ (PSP)

PubMed Central

Hsieh, Tze-chen; Wu, Peili; Park, Spencer; Wu, Joseph M

2006-01-01

Background I'm-Yunity™ (PSP) is a mushroom extract derived from deep-layer cultivated mycelia of the patented Cov-1 strain of Coriolus versicolor (CV), which contains as its main bioactive ingredient a family of polysaccharo-peptide with heterogeneous charge properties and molecular sizes. I'm-Yunity™ (PSP) is used as a dietary supplement by cancer patients and by individuals diagnosed with various chronic diseases. Laboratory studies have shown that I'm-Yunity™ (PSP) enhances immune functions and also modulates cellular responses to external challenges. Recently, I'm-Yunity™ (PSP) was also reported to exert potent anti-tumorigenic effects, evident by suppression of cell proliferation and induction of apoptosis in malignant cells. We investigate the mechanisms by which I'm-Yunity™ (PSP) elicits these effects. Methods Human leukemia HL-60 and U-937 cells were incubated with increasing doses of aqueous extracts of I'm-Yunity™ (PSP). Control and treated cells were harvested at various times and analyzed for changes in: (1) cell proliferation and viability, (2) cell cycle phase transition, (3) induction of apoptosis, (4) expression of cell cycle, apoptogenic/anti-apoptotic, and extracellular regulatory proteins. Results Aqueous extracts of I'm-Yunity™ (PSP) inhibited cell proliferation and induced apoptosis in HL-60 and U-937 cells, accompanied by a cell type-dependent disruption of the G1/S and G2/M phases of cell cycle progression. A more pronounced growth suppression was observed in treated HL-60 cells, which was correlated with time- and dose-dependent down regulation of the retinoblastoma protein Rb, diminution in the expression of anti-apoptotic proteins bcl-2 and survivin, increase in apoptogenic proteins bax and cytochrome c, and cleavage of poly(ADP-ribose) polymerase (PARP) from its native 112-kDa form to the 89-kDa truncated product. Moreover, I'm-Yunity™ (PSP)-treated HL-60 cells also showed a substantial decrease in p65 and to a lesser degree p50 forms of transcription factor NF-κB, which was accompanied by a reduction in the expression of cyclooxygenase 2 (COX2). I'm-Yunity™ (PSP) also elicited an increase in STAT1 (signal transducer and activator of transcription) and correspondingly, decrease in the expression of activated form of ERK (extracellular signal-regulated kinase). Conclusion Aqueous extracts of I'm-Yunity™ (PSP) induces cell cycle arrest and alterations in the expression of apoptogenic/anti-apoptotic and extracellular signaling regulatory proteins in human leukemia cells, the net result being suppression of proliferation and increase in apoptosis. These findings may contribute to the reported clinical and overall health effects of I'm-Yunity™ (PSP). PMID:16965632

Leptin suppresses non-apoptotic cell death in ischemic rat cardiomyocytes by reduction of iPLA{sub 2} activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takatani-Nakase, Tomoka, E-mail: nakase@mukogawa-u.ac.jp; Takahashi, Koichi, E-mail: koichi@mukogawa-u.ac.jp

Caspase-independent, non-apoptotic cell death is an important therapeutic target in myocardial ischemia. Leptin, an adipose-derived hormone, is known to exhibit cytoprotective effects on the ischemic heart, but the mechanisms are poorly understood. In this research, we found that pretreatment of leptin strongly suppressed ischemic-augmented nuclear shrinkage and non-apoptotic cell death on cardiomyocytes. Leptin was also shown to significantly inhibit the activity of iPLA{sub 2}, which is considered to play crucial roles in non-apoptotic cell death, resulting in effective prevention of ischemia-induced myocyte death. These findings provide the first evidence of a protective mechanism of leptin against ischemia-induced non-apoptotic cardiomyocyte death.more » - Highlights: • Myocardial ischemia-model induces in caspase-independent, non-apoptotic cell death. • Leptin strongly inhibits ischemic-augmented non-apoptotic cell death. • Leptin reduces iPLA{sub 2} activity, leading to avoidance of non-apoptotic cell death.« less

Two Closely Related Ubiquitin C-Terminal Hydrolase Isozymes Function as Reciprocal Modulators of Germ Cell Apoptosis in Cryptorchid Testis

PubMed Central

Kwon, Jungkee; Wang, Yu-Lai; Setsuie, Rieko; Sekiguchi, Satoshi; Sato, Yae; Sakurai, Mikako; Noda, Mami; Aoki, Shunsuke; Yoshikawa, Yasuhiro; Wada, Keiji

2004-01-01

The experimentally induced cryptorchid mouse model is useful for elucidating the in vivo molecular mechanism of germ cell apoptosis. Apoptosis, in general, is thought to be partly regulated by the ubiquitin-proteasome system. Here, we analyzed the function of two closely related members of the ubiquitin C-terminal hydrolase (UCH) family in testicular germ cell apoptosis experimentally induced by cryptorchidism. The two enzymes, UCH-L1 and UCH-L3, deubiquitinate ubiquitin-protein conjugates and control the cellular balance of ubiquitin. The testes of gracile axonal dystrophy (gad) mice, which lack UCH-L1, were resistant to cryptorchid stress-related injury and had reduced ubiquitin levels. The level of both anti-apoptotic (Bcl-2 family and XIAP) and prosurvival (pCREB and BDNF) proteins was significantly higher in gad mice after cryptorchid stress. In contrast, Uchl3 knockout mice showed profound testicular atrophy and apoptotic germ cell loss after cryptorchid injury. Ubiquitin level was not significantly different between wild-type and Uchl3 knockout mice, whereas the levels of Nedd8 and the apoptotic proteins p53, Bax, and caspase3 were elevated in Uchl3 knockout mice. These results demonstrate that UCH-L1 and UCH-L3 function differentially to regulate the cellular levels of anti-apoptotic, prosurvival, and apoptotic proteins during testicular germ cell apoptosis. PMID:15466400

Maternal choline supplementation during murine pregnancy modulates placental markers of inflammation, apoptosis and vascularization in a fetal sex-dependent manner.

PubMed

Kwan, Sze Ting Cecilia; King, Julia H; Yan, Jian; Jiang, Xinyin; Wei, Emily; Fomin, Vladislav G; Roberson, Mark S; Caudill, Marie A

2017-05-01

Normal placental vascular development is influenced by inflammatory, angiogenic and apoptotic processes, which may be modulated by choline through its role in membrane biosynthesis, cellular signaling and gene expression regulation. The current study examined the effect of maternal choline supplementation (MCS) on placental inflammatory, angiogenic and apoptotic processes during murine pregnancy. Pregnant dams were randomized to receive 1, 2 or 4 times (X) the normal choline content of rodent diets, and tissues were harvested on embryonic day (E) 10.5, 12.5, 15.5 or 18.5 for gene expression, protein abundance and immunohistochemical analyses. The choline-induced changes in the inflammatory and angiogenic markers were a function of fetal sex. Specifically, 4X (versus 1X) choline reduced the transcript (P ≤ 0.05) and protein (P ≤ 0.06) expression of TNF-a and IL-1β in the male placentas at E10.5 and E18.5, respectively. In the female placentas, 4X (versus 1X) choline modulated the transcript expression of Il1b in a biphasic pattern with reduced Il1b at E12.5 (P = 0.045) and E18.5 (P = 0.067) but increased Il1b at E15.5 (P = 0.031). MCS also induced an upregulation of Vegfa expression in the female placentas at E15.5 (P = 0.034; 4X versus 2X) and E18.5 (P = 0.026; 4X versus 1X). MCS decreased (P = 0.011; 4X versus 1X) placental apoptosis at E10.5. Additionally, the luminal area of the maternal spiral arteries was larger (P ≤ 0.05; 4X versus 1X) in response to extra choline throughout gestation. MCS during murine pregnancy has fetal sex-specific effects on placental inflammation and angiogenesis, with possible consequences on placental vascular development. Copyright © 2017 Elsevier Ltd. All rights reserved.

CAS role in the brain apoptosis of Bufo arenarum induced by cypermethrin.

PubMed

Izaguirre, M F; Vergara, M N; Casco, V H

2006-08-01

CAS might have a key role in the apoptosis induced by toxins, acting as anti-apoptotic factor, stimulating the cellular proliferation and the cell contact stabilization. To start to elucidate their role in the brain apoptosis of Bufo arenarum induced by cypermethrin (CY), the expression patterns of CAS and several cell adhesion molecules (CAMs) were established. Bufo arenarum tadpoles of the control and acute bioassay survival at different doses (39, 156, 625 and 2,500 microg CY/L) and times (24, 48, 72 and 96 h) of CY treatment were fixed in Carnoy, embedded in paraffin and sectioned. CAS and CAMs expression was determined by immunofluorescence and immunohistochemistry, respectively. When the bioassay starts, CAS increases suggesting a proliferative or regenerative effect, but decreases when the doses and/or the biocide exposure time increases, suggesting compromise of the cellular cycle control and trigger of an apoptotic wave. However, these neurotoxic mechanisms should not involve degradation of N-cadherin and alpha-catenin, in contrast of beta-catenin and axonal N-CAM180, at least in the initial apoptotic phase. Additionally, an adhesion compensatory mechanism by N-CAM180 is observed in the neuron cell body. These results suggest a dual role of CAS in the cellular cycle control during the CY-induced apoptosis: induction of cell proliferation and stabilization of the cell-cell junctions by modulating CAMs expression.

Suppression of osteoblastic phenotypes and modulation of pro- and anti-apoptotic features in normal human osteoblastic cells under a vector-averaged gravity condition.

PubMed

Nakamura, Hiroshi; Kumei, Yasuhiro; Morita, Sadao; Shimokawa, Hitoyata; Ohya, Keiichi; Shinomiya, Kenichi

2003-06-01

Spaceflight and bed rest induce loss of bone mass. A number of in vivo and in vitro studies have been conducted to clarify the mechanisms, however, the results have been conflicting. The purpose of this study was to investigate the effects of gravity unloading on proliferation, phenotypes, and apoptosis of normal human osteoblastic cells in the presence of 1alpha,25-dihydroxyvitamin D3. We used a vector-averaged gravity condition generated by clinostat rotation to simulate gravity unloading. Clinostat rotation did not affect the cell proliferation. On the first day, the mRNA levels for osteocalcin, ALP, CBFA1, VDR, RANKL, and OPG were reduced by clinostat rotation to 21%, 65%, 62%, 52%, 43%, and 54% of control, respectively. ALP activity was decreased to 75% of control. On the second day, the mRNA levels for osteocalcin and RANKL were reduced to 77% and 61% of control, respectively. The decreased VDR mRNA level might be responsible for the reduction for mRNA levels for osteocalcin, RANKL, and OPG. Clinostat rotation increased the pro-apoptotic index (Bax/Bcl-2 ratio) but did not induce apoptosis due to the simultaneous upregulation of the anti-apoptotic XIAP. Reduction of osteoblast responsiveness to 1alpha,25-dihydroxyvitamin D3 might be involved in osteopenia that is induced by gravity unloading.

C-Phycocyanin protects against acute tributyltin chloride neurotoxicity by modulating glial cell activity along with its anti-oxidant and anti-inflammatory property: A comparative efficacy evaluation with N-acetyl cysteine in adult rat brain.

PubMed

Mitra, Sumonto; Siddiqui, Waseem A; Khandelwal, Shashi

2015-08-05

Spirulina is a widely used health supplement and is a dietary source of C-Phycocyanin (CPC), a potent anti-oxidant. We have previously reported the neurotoxic potential of tributyltin chloride (TBTC), an environmental pollutant and potent biocide. In this study, we have evaluated the protective efficacy of CPC against TBTC induced neurotoxicity. To evaluate the extent of neuroprotection offered by CPC, its efficacy was compared with the degree of protection offered by N-acetylcysteine (NAC) (a well known neuroprotective drug, taken as a positive control). Male Wistar rats (28 day old) were administered with 20mg/kg TBTC (oral) and 50mg/kg CPC or 50mg/kg NAC (i.p.), alone or in combination, and various parameters were evaluated. These include blood-brain barrier (BBB) damage; redox parameters (ROS, GSH, redox pathway associated enzymes, oxidative stress markers); inflammatory, cellular, and stress markers; apoptotic proteins and in situ cell death assay (TUNEL). We observed increased CPC availability in cortical tissue following its administration. Although BBB associated proteins like claudin-5, p-glycoprotein and ZO-1 were restored, CPC/NAC failed to protect against TBTC induced overall BBB permeability (Evans blue extravasation). Both CPC and NAC remarkably reduced oxidative stress and inflammation. NAC effectively modulated redox pathway associated enzymes whereas CPC countered ROS levels efficiently. Interestingly, CPC and NAC were equivalently capable of reducing apoptotic markers, astroglial activation and cell death. This study illustrates the various pathways involved in CPC mediated neuroprotection against this environmental neurotoxicant and highlights its capability to modulate glial cell activity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Curcumin induces apoptotic cell death of activated human CD4+ T cells via increasing endoplasmic reticulum stress and mitochondrial dysfunction.

PubMed

Zheng, Min; Zhang, Qinggao; Joe, Yeonsoo; Lee, Bong Hee; Ryu, Do Gon; Kwon, Kang Beom; Ryter, Stefan W; Chung, Hun Taeg

2013-03-01

Curcumin, a natural polyphenolic antioxidant compound, exerts well-known anti-inflammatory and immunomodulatory effects, the latter which can influence the activation of immune cells including T cells. Furthermore, curcumin can inhibit the expression of pro-inflammatory cytokines and chemokines, through suppression of the NF-κB signaling pathway. The beneficial effects of curcumin in diseases such as arthritis, allergy, asthma, atherosclerosis, diabetes and cancer may be due to its immunomodulatory properties. We studied the potential of curcumin to modulate CD4+ T cells-mediated autoimmune disease, by examining the effects of this compound on human CD4+ lymphocyte activation. Stimulation of human T cells with PHA or CD3/CD28 induced IL-2 mRNA expression and activated the endoplasmic reticulum (ER) stress response. The treatment of T cells with curcumin induced the unfolded protein response (UPR) signaling pathway, initiated by the phosphorylation of PERK and IRE1. Furthermore, curcumin increased the expression of the ER stress associated transcriptional factors XBP-1, cleaved p50ATF6α and C/EBP homologous protein (CHOP) in human CD4+ and Jurkat T cells. In PHA-activated T cells, curcumin further enhanced PHA-induced CHOP expression and reduced the expression of the anti-apoptotic protein Bcl-2. Finally, curcumin treatment induced apoptotic cell death in activated T cells via eliciting an excessive ER stress response, which was reversed by the ER-stress inhibitor 4-phenylbutyric acid or transfection with CHOP-specific siRNA. These results suggest that curcumin can impact both ER stress and mitochondria functional pathways, and thereby could be used as a promising therapy in the context of Th1-mediated autoimmune diseases. Copyright © 2013 Elsevier B.V. All rights reserved.

Silymarin and its active component silibinin act as novel therapeutic alternatives for salivary gland cancer by targeting the ERK1/2-Bim signaling cascade.

PubMed

Choi, Eun-Sun; Oh, Sejun; Jang, Boonsil; Yu, Hyun-Ju; Shin, Ji-Ae; Cho, Nam-Pyo; Yang, In-Hyoung; Won, Dong-Hoon; Kwon, Hye-Jeong; Hong, Seong Doo; Cho, Sung-Dae

2017-06-01

Approximately 20% of all salivary gland cancer patients who are treated with current treatment modalities will ultimately develop metastases. Its most common form, mucoepidermoid carcinoma (MEC) is a highly aggressive tumor with an overall 5-year survival rate of ~30%. Until now, several chemotherapeutic drugs have been tested for the treatment of salivary gland tumors, but the results have been disappointing and the drugs often cause unwanted side effects. Therefore, several recent studies have focused on the potential of alternative and/or complementary therapeutic options, including the use of silymarin. The effects of silymarin and its active component silibinin on salivary gland cancer-derived MC3 and HN22 cells and their underlying molecular mechanisms were examined using trypan blue exclusion, 4'-6-diamidino-2-phenylindole (DAPI) staining, Live/Dead, Annexin V/PI staining, mitochondrial membrane potential (ΔΨm) measurement, quantitative RT-PCR, soft agar colony formation and Western blotting analyses. We found that silymarin and silibinin dramatically increased the expression of the pro-apoptotic protein Bim in a concentration- and time-dependent manner and, concomitantly, induced apoptosis in MC3 and HN22 cells. We also found that ERK1/2 signaling inhibition successfully sensitized these cells to the apoptotic effects of silymarin and silibinin, which indicates that the ERK1/2 signaling pathway may act as an upstream regulator that modulates the silymarin/silibinin-induced Bim signaling pathway. Taken together, we conclude that ERK1/2 signaling pathway inhibition by silymarin and silibinin increases the expression of the pro-apoptotic Bcl-2 family member Bim which, subsequently, induces mitochondria-mediated apoptosis in salivary gland cancer-derived cells.

Butyrate-induced apoptotic cascade in colonic carcinoma cells: modulation of the beta-catenin-Tcf pathway and concordance with effects of sulindac and trichostatin A but not curcumin.

PubMed

Bordonaro, M; Mariadason, J M; Aslam, F; Heerdt, B G; Augenlicht, L H

1999-10-01

Short-chain fatty acids play a critical role in colonic homeostasis because they stimulate pathways of growth arrest, differentiation, and apoptosis. These effects have been well characterized in colonic cell lines in vitro. We investigated the role of beta-catenin-Tcf signaling in these responses to butyrate and other well-characterized inducers of apoptosis of colonic epithelial cells. Unlike wild-type APC, which down-regulates Tcf activity, butyrate, as well as sulindac and trichostatin A, all inducers of G0-G1 cell cycle arrest and apoptosis in the SW620 colonic carcinoma cell line, up-regulate Tcf activity. In contrast, structural analogues of butyrate that do not induce cell cycle arrest or apoptosis and curcumin, which stimulates G2-M arrest without inducing apoptosis, do not alter Tcf activity. Similar to the cell cycle arrest and apoptotic cascade induced by butyrate, the up-regulation of Tcf activity is dependent upon the presence of a mitochondrial membrane potential, unlike the APC-induced down-regulation, which is insensitive to collapse of the mitochondrial membrane potential. Moreover, the butyrate-induced increase in Tcf activity, which is reflected in an increase in beta-catenin-Tcf complex formation, is independent of the down-regulation caused by expression of wild-type APC. Thus, butyrate and wild-type APC have different and independent effects on beta-catenin-Tcf signaling. These data are consistent with other reports that suggest that the absence of wild-type APC, associated with the up-regulation of this signaling pathway, is linked to the probability of a colonic epithelial cell entering an apoptotic cascade.

Effects of flavocoxid, a dual inhibitor of COX and 5-lipoxygenase enzymes, on benign prostatic hyperplasia

PubMed Central

Altavilla, D; Minutoli, L; Polito, F; Irrera, N; Arena, S; Magno, C; Rinaldi, M; Burnett, BP; Squadrito, F; Bitto, A

2012-01-01

BACKGROUND AND PURPOSE Inflammation plays a key role in the development of benign prostatic hyperplasia (BPH). Eicosanoids derived from the COX and 5-lipoxygenase (5-LOX) pathways are elevated in the enlarging prostate. Flavocoxid is a novel flavonoid–based ‘dual inhibitor’ of the COX and 5-LOX enzymes. This study evaluated the effects of flavocoxid in experimental BPH. EXPERIMENTAL APPROACH Rats were treated daily with testosterone propionate (3 mg·kg−1 s.c.) or its vehicle for 14 days to induce BPH. Animals receiving testosterone were randomized to receive vehicle (1 mL·kg−1, i.p.) or flavocoxid (20 mg·kg−1, i.p.) for 14 days. Histological changes, eicosanoid content and mRNA and protein levels for apoptosis-related proteins and growth factors were assayed in prostate tissue. The effects of flavocoxid were also tested on human prostate carcinoma PC3 cells. KEY RESULTS Flavocoxid reduced prostate weight and hyperplasia, blunted inducible expression of COX-2 and 5-LOX as well as the increased production of PGE2 and leukotriene B4 (LTB4), enhanced pro-apoptotic Bax and caspase-9 and decreased the anti-apoptotic Bcl-2 mRNA. Flavocoxid also reduced EGF and VEGF expression. In PC3 cells, flavocoxid stimulated apoptosis and inhibited growth factor expression. Flavocoxid-mediated induction of apoptosis was inhibited by the pan-caspase inhibitor, Z-VAD-FMK, in PC3 cells, suggesting an essential role of caspases in flavocoxid-mediated apoptosis during prostatic growth. CONCLUSION AND IMPLICATIONS Our results show that a ‘dual inhibitor’ of the COX and 5-LOX enzymes, such as flavocoxid, might represent a rational approach to reduce BPH through modulation of eicosanoid production and a caspase-induced apoptotic mechanism. PMID:22471974

Effects of flavocoxid, a dual inhibitor of COX and 5-lipoxygenase enzymes, on benign prostatic hyperplasia.

PubMed

Altavilla, D; Minutoli, L; Polito, F; Irrera, N; Arena, S; Magno, C; Rinaldi, M; Burnett, B P; Squadrito, F; Bitto, A

2012-09-01

Inflammation plays a key role in the development of benign prostatic hyperplasia (BPH). Eicosanoids derived from the COX and 5-lipoxygenase (5-LOX) pathways are elevated in the enlarging prostate. Flavocoxid is a novel flavonoid-based 'dual inhibitor' of the COX and 5-LOX enzymes. This study evaluated the effects of flavocoxid in experimental BPH. Rats were treated daily with testosterone propionate (3 mg·kg(-1)  s.c.) or its vehicle for 14 days to induce BPH. Animals receiving testosterone were randomized to receive vehicle (1 mL·kg(-1) , i.p.) or flavocoxid (20 mg·kg(-1) , i.p.) for 14 days. Histological changes, eicosanoid content and mRNA and protein levels for apoptosis-related proteins and growth factors were assayed in prostate tissue. The effects of flavocoxid were also tested on human prostate carcinoma PC3 cells. Flavocoxid reduced prostate weight and hyperplasia, blunted inducible expression of COX-2 and 5-LOX as well as the increased production of PGE(2) and leukotriene B(4) (LTB(4) ), enhanced pro-apoptotic Bax and caspase-9 and decreased the anti-apoptotic Bcl-2 mRNA. Flavocoxid also reduced EGF and VEGF expression. In PC3 cells, flavocoxid stimulated apoptosis and inhibited growth factor expression. Flavocoxid-mediated induction of apoptosis was inhibited by the pan-caspase inhibitor, Z-VAD-FMK, in PC3 cells, suggesting an essential role of caspases in flavocoxid-mediated apoptosis during prostatic growth. Our results show that a 'dual inhibitor' of the COX and 5-LOX enzymes, such as flavocoxid, might represent a rational approach to reduce BPH through modulation of eicosanoid production and a caspase-induced apoptotic mechanism. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

Effects of the novel angiotensin II receptor type I antagonist, fimasartan on myocardial ischemia/reperfusion injury.

PubMed

Han, Jin; Park, Sung-Ji; Thu, Vu Thi; Lee, Sung-Ryul; Long, Le Thanh; Kim, Hyoung Kyu; Kim, Nari; Park, Seung Woo; Jeon, Eun-Seok; Kim, Eun-Ji; Yoon, Chang-Hwan; Cho, Goo-Young; Choi, Dong-Ju

2013-10-03

The aim of this study was to investigate the cardioprotective effect of fimasartan, a newly developed angiotensin II receptor type I blocker (ARB), against myocardial ischemia/reperfusion (I/R) injury and to identify the mechanism by which it reduces mitochondrial damage. Fimasartan was administered intravenously to Sprague-Dawley rats (3mg/kg), cardiomyocytes (50 μM), and H9c2 cells (50 μM) before ischemia or hypoxia. Myocardial infarction (MI), echocardiograms, DNA fragmentation, terminal deoxynucleotidyl transferase-mediated dUTP in situ nick-end labeling, immunoblotting, oxygen consumption, confocal microscopic appearance, and L-type Ca(2+) current (ICa,L) were then assessed. Fimasartan pretreatment remarkably reduced the rate of MI and improved cardiac performance well after I/R (n = 9/group). Fimasartan also reduced apoptotic cell death both in vivo and in hypoxia/reoxygenation (H/R)-treated H9c2 cells (n = 5~8/group). H/R-induced mitochondrial O2(-) production and collapse of membrane potential were markedly attenuated in fimasartan-treated cardiomyocytes (n = 4 ~ 6/group). Additionally, mitochondrial Ca(2+) overload during reoxygenation was suppressed by fimasartan (n = 4~6/group), and this was found to be possibly related to the inhibition of ICa,L and mitochondrial Ca(2+) uniporter. Furthermore, fimasartan pretreatment increased phosphorylations of Akt and glycogen synthase kinase-3β (n = 5 ~ 7/group), decreased pro-apoptotic p53 levels, and increased anti-apoptotic Bcl-2 levels (n = 4) during reperfusion. Fimasartan preconditioning has the potential to modulate Bcl-2 and suppress I/R-induced Ca(2+) overload by inhibiting ICa,L and MCU. These beneficial effects could prevent the mitochondrial dysfunction and apoptosis accompanied by I/R. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Amelioration of nandrolone decanoate-induced testicular and sperm toxicity in rats by taurine: effects on steroidogenesis, redox and inflammatory cascades, and intrinsic apoptotic pathway.

PubMed

Ahmed, Maha A E

2015-02-01

The wide abuse of the anabolic steroid nandrolone decanoate by athletes and adolescents for enhancement of sporting performance and physical appearance may be associated with testicular toxicity and infertility. On the other hand, taurine; a free β-amino acid with remarkable antioxidant activity, is used in taurine-enriched beverages to boost the muscular power of athletes. Therefore, the purpose of this study was to investigate the mechanisms of the possible protective effects of taurine on nandrolone decanoate-induced testicular and sperm toxicity in rats. To achieve this aim, male Wistar rats were randomly distributed into four groups and administered either vehicle, nandrolone decanoate (10mg/kg/week, I.M.), taurine (100mg/kg/day, p.o.) or combination of taurine and nandrolone decanoate, for 8 successive weeks. Results of the present study showed that taurine reversed nandrolone decanoate-induced perturbations in sperm characteristics, normalized serum testosterone level, and restored the activities of the key steroidogenic enzymes; 3β-HSD, and 17β-HSD. Moreover, taurine prevented nandrolone decanoate-induced testicular toxicity and DNA damage by virtue of its antioxidant, anti-inflammatory, and anti-apoptotic effects. This was evidenced by taurine-induced modulation of testicular LDH-x activity, redox markers (MDA, NO, GSH contents, and SOD activity), inflammatory indices (TNF-α, ICAM-1 levels, and MMP-9 gene expression), intrinsic apoptotic pathway (cytochrome c gene expression and caspase-3 content), and oxidative DNA damage markers (8-OHdG level and comet assay). In conclusion, at the biochemical and histological levels, taurine attenuated nandrolone decanoate-induced poor sperm quality and testicular toxicity in rats. Copyright © 2014 Elsevier Inc. All rights reserved.

Ascorbyl Stearate Promotes Apoptosis Through Intrinsic Mitochondrial Pathway in HeLa Cancer Cells.

PubMed

Mane, Shirish D; Thoh, Maikho; Sharma, Deepak; Sandur, Santosh K; Naidu, K Akhilender

2016-12-01

Ascorbic acid is proposed to have antitumor potential against certain cancer types but has the limitation of requiring high doses for treating cancer. Ascorbyl stearate (ASC-S) is a fatty acid ester derivative of ascorbic acid with comparable potent apoptotic activity. The present study was aimed at understanding the pathway involved in apoptotic activity of ASC-S in cervical cancer cells. The effect of ASC-S on reactive oxygen species (ROS), and mitochondrial membrane potential (MMP) was studied in HeLa cells. Furthermore, the dose-dependent effect of ASC-S on release of cytochrome c, pro-caspase-9, caspase-3, BH3 interacting-domain death agonist (BID), truncated BH3 interacting-domain death agonist (t-BID), FAS ligand (FASL) and transcription factors nuclear factor-kappa B (NF-ĸB), nuclear factor of activated T-cells (NFAT) and activator protein-1 (AP1) were studied in HeLa cells. Treatment of HeLa cells with ASC-S significantly increased the MMP. The modulation of MMP resulted in cleavage of BID, expression of FAS, cleavage of pro-caspase-9 and release of cytochrome c into cytosol. In addition, ASC-S treatment resulted in deregulation of transcription factors NF-ĸB, NFAT and AP1, which play an important role in the development of inflammation and cancer. Our data, for the first time, suggest that ASC-S has an apoptotic effect against HeLa cells by inducing change in mitochondrial membrane permeability, cytochrome c release and subsequent activation of caspase-3 and NF-ĸB. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Nitric oxide-mediated activity in anti-cancer photodynamic therapy.

PubMed

Rapozzi, Valentina; Della Pietra, Emilia; Zorzet, Sonia; Zacchigna, Marina; Bonavida, Benjamin; Xodo, Luigi Emilio

2013-04-01

Cell recurrence in cancer photodynamic therapy (PDT) is an important issue that is poorly understood. It is becoming clear that nitric oxide (NO) is a modulator of PDT. By acting on the NF-κB/Snail/RKIP survival/anti-apoptotic loop, NO can either stimulate or inhibit apoptosis. We found that pheophorbide a/PDT (Pba/PDT) induces the release of NO in B78-H1 murine amelanotic melanoma cells in a concentration-dependent manner. Low-dose PDT induces low NO levels by stimulating the anti-apoptotic nature of the above loop, whereas high-dose PDT stimulates high NO levels inhibiting the loop and activating apoptosis. When B78-H1 cells are treated with low-dose Pba/PDT and DETA/NO, an NO-donor, intracellular NO increases and cell growth is inhibited according to scratch-wound and clonogenic assays. Western blot analyses showed that the combined treatment reduces the expression of the anti-apoptotic NF-κB and Snail gene products and increases the expression of the pro-apoptotic RKIP gene product. The combined effect of Pba and DETA/NO was also tested in C57BL/6 mice bearing a syngeneic B78-H1 melanoma. We used pegylated Pba (mPEG-Pba) due to its better pharmacokinetics compared to free Pba. mPEG-Pba (30 mg/Kg) and DETA/NO (0.4 mg/Kg) were i.p. injected either as a single molecule or in combination. After photoactivation at 660 nM (fluence of 193 J/cm(2)), the combined treatment delays tumor growth more efficiently than each individual treatment (p<0.05). Taken together, our results showed that the efficacy of PDT is strengthened when the photosensitizer is used in combination with an NO donor. Copyright © 2013 Elsevier Inc. All rights reserved.

Attenuation of dexamethasone-induced cell death in multiple myeloma is mediated by miR-125b expression

PubMed Central

Murray, Megan Y.; Rushworth, Stuart A.; Zaitseva, Lyubov; Bowles, Kristian M.; MacEwan, David J.

2013-01-01

Dexamethasone is a key front-line chemotherapeutic for B-cell malignant multiple myeloma (MM). Dexamethasone modulates MM cell survival signaling but fails to induce marked cytotoxicity when used as a monotherapy. We demonstrate here the mechanism behind this insufficient responsiveness of MM cells toward dexamethasone, revealing in MM a dramatic anti-apoptotic role for microRNA (miRNA)-125b in the insensitivity toward dexamethasone-induced apoptosis. MM cells responding to dexamethasone exhibited enhanced expression of oncogenic miR-125b. Dexamethasone also induced expression of miR-34a, which acts to suppress SIRT1 deacetylase, and thus allows maintained acetylation and inactivation of p53. p53 mRNA is also suppressed by miR-125b targeting. Reporter assays showed that both these dexamethasone-induced miRNAs act downstream of their target genes to prevent p53 tumor suppressor actions and, ultimately, resist cytotoxic responses in MM. Use of antisense miR-125b transcripts enhanced expression of pro-apoptotic p53, repressed expression of anti-apoptotic SIRT1 and, importantly, significantly enhanced dexamethasone-induced cell death responses in MM. Pharmacological manipulations showed that the key regulation enabling complete dexamethasone sensitivity in MM cells lies with miR-125b. In summary, dexamethasone-induced miR-125b induces cell death resistance mechanisms in MM cells via the p53/miR-34a/SIRT1 signaling network and provides these cells with an enhanced level of resistance to cytotoxic chemotherapeutics. Clearly, such anti-apoptotic mechanisms will need to be overcome to more effectively treat nascent, refractory and relapsed MM patients. These mechanisms provide insight into the role of miRNA regulation of apoptosis and their promotion of MM cell proliferative mechanisms. PMID:23759586

Regulation of T lymphocyte apoptotic markers is associated to cell activation during the acute phase of dengue.

PubMed

Torrentes-Carvalho, Amanda; Marinho, Cintia Ferreira; de Oliveira-Pinto, Luzia Maria; de Oliveira, Débora Batista; Damasco, Paulo Vieira; Cunha, Rivaldo Venâncio; de Souza, Luiz José; de Azeredo, Elzinandes Leal; Kubelka, Claire Fernandes

2014-05-01

Dengue fever, a public health problem in Brazil, may present severe clinical manifestations as result of an increased vascular permeability and coagulation disorders. T cell activation is a critical event for an effective immune response against infection, including the production of cytokines. We aim to reveal mechanisms that modulate the virus-cell interaction, with an emphasis on cell death. Apoptosis is involved in lymphocyte homeostasis, contributes to the clearance of virus-infected cells but also may play a role in the pathogenesis. Phosphatidylserine exposure on CD8T lymphocytes from dengue patients support early apoptotic processes and loss of genomic integrity, observed by DNA fragmentation in T lymphocytes and indicating late apoptosis. These T cells express activation and cytotoxic phenotypes as revealed by CD29 and CD107a upregulation. Higher frequencies of CD95 were detected in T lymphocytes mainly in those with the cytotoxic profile (CD107a+) and lower levels of anti-apoptotic molecule Bcl-2, suggesting that both CD4+ and CD8+ T cell subsets are more susceptible to apoptosis during acute dengue. The analysis of apoptosis-related protein expression profile showed that not only molecules with pro- but also those with anti-apoptotic functions are overexpressed, indicating that survival mechanisms could be possibly protecting cells against apoptosis caused by viral, immune, oxidative and/or genotoxic stresses. These observations led us to propose that in dengue patients there is an association between T cell susceptibility to apoptosis and the activation state. The mechanisms for understanding the immunopathogenesis during dengue infection are discussed. Copyright © 2013 Elsevier GmbH. All rights reserved.

Curcumin inhibits autocrine growth hormone-mediated invasion and metastasis by targeting NF-κB signaling and polyamine metabolism in breast cancer cells.

PubMed

Coker-Gurkan, Ajda; Celik, Merve; Ugur, Merve; Arisan, Elif-Damla; Obakan-Yerlikaya, Pinar; Durdu, Zeynep Begum; Palavan-Unsal, Narcin

2018-05-16

Curcumin is assumed to be a plant-derived therapeutic drug that triggers apoptotic cell death in vitro and in vivo by affecting different molecular targets such as NF-κB. Phase I/II trial of curcumin alone or with chemotherapeutic drugs has been accomplished in pancreatic, colon, prostate and breast cancer cases. Recently, autocrine growth hormone (GH) signaling-induced cell growth, metastasis and drug resistance have been demonstrated in breast cancer. In this study, our aim was to investigate the potential therapeutic effect of curcumin by evaluating the molecular machinery of curcumin-triggered apoptotic cell death via focusing on NF-κB signaling and polyamine (PA) metabolism in autocrine GH-expressing MCF-7, MDA-MB-453 and MDA-MB-231 breast cancer cells. For this purpose, a pcDNA3.1 (+) vector with a GH gene insert was transfected by a liposomal agent in all breast cancer cells and then selection was conducted in neomycin (G418) included media. Autocrine GH-induced curcumin resistance was overcome in a dose-dependent manner and curcumin inhibited cell proliferation, invasion-metastasis and phosphorylation of p65 (Ser536), and thereby partly prevented its DNA binding activity in breast cancer cells. Moreover, curcumin induced caspase-mediated apoptotic cell death by activating the PA catabolic enzyme expressions, which led to generation of toxic by-products such as H 2 O 2 in MCF-7, MDA-MB-453 and MDA-MB-231 GH+ breast cancer cells. In addition, transient silencing of SSAT prevented curcumin-induced cell viability loss and apoptotic cell death in each breast cancer cells. In conclusion, curcumin could overcome the GH-mediated resistant phenotype via modulating cell survival, death-related signaling routes and activating PA catabolic pathway.

HSP27, 70 and 90, anti-apoptotic proteins, in clinical cancer therapy (Review).

PubMed

Wang, Xiaoxia; Chen, Meijuan; Zhou, Jing; Zhang, Xu

2014-07-01

Among the heat shock proteins (HSP), HSP27, HSP70 and HSP90 are the most studied stress-inducible HSPs, and are induced in response to a wide variety of physiological and environmental insults, thus allowing cells to survive to lethal conditions based on their powerful cytoprotective functions. Different functions of HSPs have been described to explain their cytoprotective functions, including their most basic role as molecular chaperones, that is to regulate protein folding, transport, translocation and assembly, especially helping in the refolding of misfolded proteins, as well as their anti-apoptotic properties. In cancer cells, the expression and/or activity of the three HSPs is abnormally high, and is associated with increased tumorigenicity, metastatic potential of cancer cells and resistance to chemotherapy. Associating with key apoptotic factors, they are powerful anti-apoptotic proteins, having the capacity to block the cell death process at different levels. Altogether, the properties suggest that HSP27, HSP70 and HSP90 are appropriate targets for modulating cell death pathways. In this review, we summarize the role of HSP90, HSP70 and HSP27 in apoptosis and the emerging strategies that have been developed for cancer therapy based on the inhibition of the three HSPs.

Modulation of Mcl-1 expression reduces age-related cochlear degeneration

PubMed Central

Yang, Wei Ping; Xu, Yang; Guo, Wei Wei; Liu, Hui Zhan; Hu, Bo Hua

2013-01-01

Mcl-1 is an anti-apoptotic member of the Bcl-2 family that modulates apoptosis-related signaling pathways and promotes cell survival. We have previously demonstrated a reduction of Mcl-1 expression in aging cochleae. To investigate whether restoring Mcl-1 expression would reduce aging-related cochlear degeneration, we developed a rat model of Mcl-1 overexpression. A plasmid encoding human Mcl-1/enhanced green fluorescent protein was applied to the round window of the cochlea. This in vivo treatment transfected both the sensory and supporting cells of the cochlear sensory epithelium and enhanced Mcl-1 expression at both the mRNA and the protein level. The upregulation of Mcl-1 expression reduced the progression of age-related cochlear dysfunction and sensory cell death. Furthermore, the transfection of Mcl-1 exerted its protective effect by suppressing cochlear apoptosis at the mitochondrial level. This study demonstrates that the genetic modulation of Mcl-1 expression reduces the progression of age-related cochlear degeneration. PMID:23790646

Huntingtin polyQ Mutation Impairs the 17β-Estradiol/Neuroglobin Pathway Devoted to Neuron Survival.

PubMed

Nuzzo, Maria Teresa; Fiocchetti, Marco; Totta, Pierangela; Melone, Mariarosa A B; Cardinale, Antonella; Fusco, Francesca R; Gustincich, Stefano; Persichetti, Francesca; Ascenzi, Paolo; Marino, Maria

2017-10-01

Among several mechanisms underlying the well-known trophic and protective effects of 17β-estradiol (E2) in the brain, we recently reported that E2 induces the up-regulation of two anti-apoptotic and neuroprotectant proteins: huntingtin (HTT) and neuroglobin (NGB). Here, we investigate the role of this up-regulation. The obtained results indicate that E2 promotes NGB-HTT association, induces the localization of the complex at the mitochondria, and protects SK-N-BE neuroblastoma cells and murine striatal cells, which express wild-type HTT (i.e., polyQ 7 ), against H 2 O 2 -induced apoptosis. All E2 effects were completely abolished in HTT-knocked out SK-N-BE cells and in striatal neurons expressing the mutated form of HTT (mHTT; i.e., polyQ 111 ) typical of Huntington's disease (HD). As a whole, these data provide a new function of wild-type HTT which drives E2-induced NGB in mitochondria modulating NGB anti-apoptotic activity. This new function is lost by HTT polyQ pathological expansion. These data evidence the existence of a novel E2/HTT/NGB neuroprotective axis that may play a relevant role in the development of HD therapeutics.

Curcumin attenuates paraquat-induced cell death in human neuroblastoma cells through modulating oxidative stress and autophagy.

PubMed

Jaroonwitchawan, Thiranut; Chaicharoenaudomrung, Nipha; Namkaew, Jirapat; Noisa, Parinya

2017-01-01

Paraquat is a neurotoxic agent, and oxidative stress plays an important role in neuronal cell death after paraquat exposure. In this study, we assessed the neuroprotective effect of curcumin against paraquat and explored the underlying mechanisms of curcumin in vitro. Curcumin treatment prevented paraquat-induced reactive oxygen species (ROS) and apoptotic cell death. Curcumin also exerted a neuroprotective effect by increasing the expression of anti-apoptotic and antioxidant genes. The pretreatment of curcumin significantly decreased gene expression and protein production of amyloid precursor protein. The activation of autophagy process was found defective in paraquat-induced cells, indicated by the accumulation and reduction of LC3I/II. Noteworthy, curcumin restored LC3I/II expression after the pretreatment. Collectively, curcumin demonstrated as a prominent suppressor of ROS, and could reverse autophagy induction in SH-SY5Y cells. The consequences of this were the reduction of APP production and prevention of SH-SY5Y cells from apoptosis. Altogether, curcumin potentially serves as a therapeutic agent of neurodegenerative diseases, associated with ROS overproduction and autophagy dysfunction. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Resveratrol protects HaCaT cells from ultraviolet B-induced photoaging via upregulation of HSP27 and modulation of mitochondrial caspase-dependent apoptotic pathway.

PubMed

Zhou, Fen; Huang, Xin; Pan, Yun; Cao, Di; Liu, Chuan; Liu, Yiyi; Chen, Aijun

2018-05-15

The skin is the outermost protective barrier between the internal and external environment in humans. Chronic exposure to ultraviolet (UV) radiation is a major cause of photoaging. Evidence suggests that resveratrol suppresses UVB-induced photoaging. In this study, we aimed to investigate the protective effects of resveratrol against UVB-induced photoaging in HaCaT cells and to determine the underlying mechanisms. Apoptosis of normal or HSP27-overexpressing HaCaT cells in the presence of UVB was analyzed by flow cytometry. The mRNA and protein expression levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting. Resveratrol inhibited UVB-induced apoptosis by upregulating the expression of HSP27, reducing the production of proapoptotic proteins such as p65, Bax, and cleaved caspase-3, and promoting the expression of anti-apoptotic protein Bcl-2. However, UVB irradiation on HaCaT cells pretreated with resveratrol led to the upregulation of Bax, downregulation of Bcl-2, and promotion of p65 and caspase-3 activation after silencing of HSP27 gene. These findings suggest that the inhibition of HSP27 expression can partially reverse the anti-apoptotic effect of resveratrol and confirm that resveratrol can regulate HSP27 and thus control p65 and caspase-3 activation. In summary, resveratrol plays a role in photoprotection by upregulating HSP27 expression, increasing Bcl-2/Bax ratio, and inhibiting caspase-3 activity and p65 expression. Copyright © 2018 Elsevier Inc. All rights reserved.

Eosinophil Resistance to Glucocorticoid-Induced Apoptosis is Mediated by the Transcription Factor NFIL3

PubMed Central

Pazdrak, Konrad; Moon, Young; Straub, Christof; Stafford, Susan; Kurosky, Alexander

2016-01-01

The mainstay of asthma therapy, glucocorticoids (GCs) exert their therapeutic effects through the inhibition of inflammatory signaling and induction of eosinophil apoptosis. However, laboratory and clinical observations of GC-resistant asthma suggest that GCs' effects on eosinophil viability may depend on the state of eosinophil activation. In the present study we demonstrate that eosinophils stimulated with IL-5 show impaired prop-aptoptotic response to GCs. We sought to determine the contribution of GC-mediated transactivating (TA) and transrepressing (TR) pathways in modulation of activated eosinophils' response to GC by comparing their response to the selective GC receptor (GR) agonist Compound A (CpdA) devoid of TA activity to that upon treatment with Dexamethasone (Dex). IL-5-activated eosinophils showed contrasting responses to CpdA and Dex, as IL-5-treated eosinophils showed no increase in apoptosis compared to cells treated with Dex alone, while CpdA elicited an apoptotic response regardless of IL-5 stimulation. Proteomic analysis revealed that both Nuclear Factor IL-3 (NFIL3) and Map Kinase Phosphatase 1 (MKP1) were inducible by IL-5 and enhanced by Dex; however, CpdA had no effect on NFIL3 and MKP1 expression. We found that inhibiting NFIL3 with specific siRNA or by blocking the IL-5-inducible Pim-1 kinase abrogated the protective effect of IL-5 on Dex-induced apoptosis, indicating crosstalk between IL-5 anti-apoptotic pathways and GR-mediated TA signaling occurring via the NFIL3 molecule. Collectively, these results indicate that 1) GCs' TA pathway may support eosinophil viability in IL-5-stimulated cells through synergistic upregulation of NFIL3; and 2) functional inhibition of IL-5 signaling (anti-Pim1) or the use of selective GR agonists that don't upregulate NFIL3 may be effective strategies for the restoring pro-apoptotic effect of GCs on IL-5-activated eosinophils. PMID:26880402

Intravenous apoptotic spleen cell infusion induces a TGF-beta-dependent regulatory T-cell expansion

PubMed Central

Kleinclauss, François M.; Perruche, Sylvain; Masson, Emeline; De Carvalho Bittencourt, Marcelo; Biichle, Sabeha; Remy-Martin, Jean-Paul; Ferrand, Christophe; Martin, Mael; Bittard, Hugues; Chalopin, Jean-Marc; Seilles, Estelle; Tiberghien, Pierre; Saas, Philippe

2006-01-01

Apoptotic leukocytes are endowed with immunomodulatory properties that can be used to enhance hematopoietic engraftment and prevent graft-versus-host disease. This apoptotic cell-induced tolerogenic effect is mediated by host macrophages and not recipient dendritic cells or donor phagocytes present in the bone marrow graft as evidenced by selective cell depletion and trafficking experiments. Furthermore, apoptotic cell infusion is associated with TGF-β-dependent donor CD4+CD25+ T cell expansion. Such cells have a regulatory phenotype (CD62Lhigh and intracellular CTLA-4+), express high levels of Foxp3 mRNA and exert ex vivo suppressive activity through a cell-to-cell contact mechanism. In vivo CD25 depletion after apoptotic cell infusion prevents the apoptotic spleen cell-induced beneficial effects on engraftment and graft-versus-host disease occurrence. This highlights the role of regulatory T cells in the tolerogenic effect of apoptotic spleen cell infusion. This novel association between apoptosis and regulatory T cell expansion may also contribute to preventing deleterious auto-immune responses during normal turnover. PMID:15962005

Inhibition of SIRT1 by a small molecule induces apoptosis in breast cancer cells.

PubMed

Kalle, Arunasree M; Mallika, A; Badiger, Jayasree; Alinakhi; Talukdar, Pinaki; Sachchidanand

2010-10-08

Overexpression of SIRT1, a NAD+-dependent class III histone deacetylases (HDACs), is implicated in many cancers and therefore could become a promising antitumor target. Here we demonstrate a small molecule SIRT1 inhibitor, ILS-JGB-1741(JGB1741) with potent inhibitory effects on the proliferation of human metastatic breast cancer cells, MDA-MB 231. The molecule has been designed using medicinal chemistry approach based on known SIRT1 inhibitor, sirtinol. The molecule showed a significant inhibition of SIRT1 activity compared to sirtinol. Studies on the antitumor effects of JGB on three different cancer cell lines, K562, HepG2 and MDA-MB 231 showed an IC₅₀ of 1, 10 and 0.5 μM, respectively. Further studies on MDA-MB 231 cells showed a dose-dependent increase in K9 and K382 acetylation of H3 and p53, respectively. Results also demonstrated that JGB1741-induced apoptosis is associated with increase in cytochrome c release, modulation in Bax/Bcl2 ratio and cleavage of PARP. Flowcytometric analysis showed increased percentage of apoptotic cells, decrease in mitochondrial membrane potential and increase in multicaspase activation. In conclusion, the present study indicates the potent apoptotic effects of JGB1741 in MDA-MB 231 cells. Copyright © 2010 Elsevier Inc. All rights reserved.

Lycopene modulates cholinergic dysfunction, Bcl-2/Bax balance, and antioxidant enzymes gene transcripts in monosodium glutamate (E621) induced neurotoxicity in a rat model.

PubMed

Sadek, Kadry; Abouzed, Tarek; Nasr, Sherif

2016-04-01

The effect of monosodium glutamate (MSG) on brain tissue and the relative ability of lycopene to avert these neurotoxic effects were investigated. Thirty-two male Wistar rats were distributed into 4 groups: group I, untreated (placebo); group II, injected with MSG (5 mg·kg(-1)) s.c.; group III, gastrogavaged with lycopene (10 mg·kg(-1)) p.o.; and group IV received MSG with lycopene with the same mentioned doses for 30 days. The results showed that MSG induced elevation in lipid peroxidation marker and perturbation in the antioxidant homeostasis and increased the levels of brain and serum cholinesterase (ChE), total creatine phosphokinase (CPK), creatine phosphokinase isoenzymes BB (CPK-BB), and lactate dehydrogenase (LDH). Glutathione S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT) activities and gene expression were increased and glutathione content was reduced in the MSG-challenged rats, and these effects were ameliorated by lycopene. Furthermore, MSG induced apoptosis in brain tissues reflected in upregulation of pro-apoptotic Bax while lycopene upregulated the anti-apoptotic Bcl-2. Our results indicate that lycopene appears to be highly effective in relieving the toxic effects of MSG by inhibiting lipid peroxidation and inducing modifications in the activity of cholinesterase and antioxidant pathways. Interestingly, lycopene protects brain tissue by inhibiting apoptosis signaling induced by MSG.

Novel pregnenolone derivatives modulate apoptosis via Bcl-2 family genes in hepatocellular carcinoma in vitro.

PubMed

Elhinnawi, Manar A; Mohareb, Rafat M; Rady, Hanaa M; Khalil, Wagdy K B; Abd Elhalim, Mervat M; Elmegeed, Gamal A

2018-06-10

A series of pregnenolone derivatives were synthesized and assessed for anti-cancer activity against hepatocellular carcinoma cell line (HepG2). The synthesized hetero-steroids (compounds 3, 4, 5, 6, 7, 8a and 8b) were evaluated for their cytotoxic activities using MTT (3-(4,5-Dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide) assay. Apoptotic activity was assessed using dual acridine orange/ethidium bromide staining method and DNA fragmentation assay. Pro-apoptotic genes (Bax and Bak) and anti-apoptotic genes (Bcl-2 and Bcl-xL) were analyzed using quantitative real time PCR. The results revealed that compounds 4 and 6 displayed cytotoxic activity (IC 50s , 36.97 ± 2.18 and 18.46 ± 0.64 µM, respectively), while compounds 5 and 7 exhibited weak cytotoxic activity (IC 50s , 93.87 ± 8.30 µM and 93.48 ± 4.14 µM, respectively). All synthesized heterocyclic pregnenolone derivatives induced apoptosis through DNA fragmentation. Compounds 4 and 6 increased early and late apoptotic cell percentages while compounds 3, 5, 7 and 8b increased either early or late apoptotic cell percentage. Moreover, compounds 3, 6 and 8b up-regulated the expression level of Bak gene. On the other hand, compounds 4, 5, 7 and 8a down-regulated the Bcl-2 expression level, besides, compounds 5, 7 and 8a down-regulated the Bcl-xL expression level. Compounds 5, 7, 8a and 8b increased the Bak/Bcl-xL ratio, besides, compound 8a raised the Bax/Bcl-xL ratio whereas compound 5 elevated Bax/Bcl-2 and Bak/Bcl-2 ratios. The present work introduced novel pro-apoptotic pregnenolone derivatives that acted against HepG2 cells through DNA fragmentation, apoptotic morphological changes and were able to increase the pro-apoptotic/anti-apoptotic ratios of Bcl-2 family genes. This study particularly revealed that the cytotoxic compound 4 is the most promising pro-apoptotic compound among other synthesized derivatives where it induced apoptosis (late and early) through the down-regulation of Bcl-2 gene expression level. Copyright © 2018 Elsevier Ltd. All rights reserved.

Protective effects of melittin on transforming growth factor-{beta}1 injury to hepatocytes via anti-apoptotic mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Woo-Ram; Park, Ji-Hyun; Kim, Kyung-Hyun

Melittin is a cationic, hemolytic peptide that is the main toxic component in the venom of the honey bee (Apis mellifera). Melittin has multiple effects, including anti-bacterial, anti-viral and anti-inflammatory, in various cell types. However, the anti-apoptotic mechanisms of melittin have not been fully elucidated in hepatocytes. Apoptosis contributes to liver inflammation and fibrosis. Knowledge of the apoptotic mechanisms is important to develop new and effective therapies for treatment of cirrhosis, portal hypertension, liver cancer, and other liver diseases. In the present study, we investigated the anti-apoptotic effect of melittin on transforming growth factor (TGF)-{beta}1-induced apoptosis in hepatocytes. TGF-{beta}1-treated hepatocytesmore » were exposed to low doses (0.5 and 1 {mu}g/mL) and high dose (2 {mu}g/mL) of melittin. The low doses significantly protected these cells from DNA damage in TGF-{beta}1-induced apoptosis compared to the high dose. Also, melittin suppressed TGF-{beta}1-induced apoptotic activation of the Bcl-2 family and caspase family of proteins, which resulted in the inhibition of poly-ADP-ribose polymerase (PARP) cleavage. These results demonstrate that TGF-{beta}1 induces hepatocyte apoptosis and that an optimal dose of melittin exerts anti-apoptotic effects against TGF-{beta}1-induced injury to hepatocytes via the mitochondrial pathway. These results suggest that an optimal dose of melittin can serve to protect cells against TGF-{beta}1-mediated injury. - Highlights: > We investigated the anti-apoptotic effect of melittin on TGF-{beta}1-induced hepatocyte. > TGF-{beta}1 induces hepatocyte apoptosis. > TGF-{beta}1-treated hepatocytes were exposed to low doses and high dose of melittin. > Optimal dose of melittin exerts anti-apoptotic effects to hepatocytes.« less

Modulatory effects of metformin on mutagenicity and epithelial tumor incidence in doxorubicin-treated Drosophila melanogaster.

PubMed

Oliveira, Victor Constante; Constante, Sarah Alves Rodrigues; Orsolin, Priscila Capelari; Nepomuceno, Júlio César; de Rezende, Alexandre Azenha Alves; Spanó, Mário Antônio

2017-08-01

Metformin (MET) is an anti-diabetic drug used to prevent hepatic glucose release and increase tissue insulin sensitivity. Diabetic cancer patients are on additional therapy with anticancer drugs. Doxorubicin (DXR) is a cancer chemotherapeutic agent that interferes with the topoisomerase II enzyme and generates free radicals. MET (2.5, 5, 10, 25 or 50 mM) alone was examined for mutagenicity, recombinogenicity and carcinogenicity, and combined with DXR (0.4 mM) for antimutagenicity, antirecombinogenicity and anticarcinogenicity, using the Somatic Mutation and Recombination Test and the Test for Detecting Epithelial Tumor Clones in Drosophila melanogaster. MET alone did not induce mutation or recombination. Modulating effects of MET on DXR-induced DNA damage were observed at the highest concentrations. In the evaluation of carcinogenesis, MET alone did not induce tumors. When combined with DXR, MET also reduced the DXR-induced tumors at the highest concentrations. Therefore, in the present experimental conditions, MET alone did not present mutagenic/recombinogenic/carcinogenic effects, but it was able to modulate the effect of DXR in the induction of DNA damage and of tumors in D. melanogaster. It is believed that this modulating effect is mainly related to the antioxidant, anti-inflammatory and apoptotic effects of this drug, although such effects have not been directly evaluated. Copyright © 2017 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yeung, Y.-S.; Yip, C.-W.; Hon, C.-C.

We have previously demonstrated that over-expression of spike protein (S) of severe acute respiratory syndrome coronavirus (SARS-CoV) or its C-terminal subunit (S2) is sufficient to induce apoptosis in vitro. To further investigate the possible roles of S2 in SARS-CoV-induced apoptosis and pathogenesis of SARS, we characterized the host expression profiles induced upon S2 over-expression in Vero E6 cells by oligonucleotide microarray analysis. Possible activation of mitochondrial apoptotic pathway in S2 expressing cells was suggested, as evidenced by the up-regulation of cytochrome c and down-regulation of the Bcl-2 family anti-apoptotic members. Inhibition of Bcl-2-related anti-apoptotic pathway was further supported by themore » diminution of S2-induced apoptosis in Vero E6 cells over-expressing Bcl-xL. In addition, modulation of CCN E2 and CDKN 1A implied the possible control of cell cycle arrest at G1/S phase. This study is expected to extend our understanding on the pathogenesis of SARS at a molecular level.« less

Bifidobacterium breve reduces apoptotic epithelial cell shedding in an exopolysaccharide and MyD88-dependent manner

PubMed Central

Hughes, K. R.; Harnisch, L. C.; Alcon-Giner, C.; Mitra, S.; Wright, C. J.; Ketskemety, J.

2017-01-01

Certain members of the microbiota genus Bifidobacterium are known to positively influence host well-being. Importantly, reduced bifidobacterial levels are associated with inflammatory bowel disease (IBD) patients, who also have impaired epithelial barrier function, including elevated rates of apoptotic extrusion of small intestinal epithelial cells (IECs) from villi—a process termed ‘cell shedding’. Using a mouse model of pathological cell shedding, we show that mice receiving Bifidobacterium breve UCC2003 exhibit significantly reduced rates of small IEC shedding. Bifidobacterial-induced protection appears to be mediated by a specific bifidobacterial surface exopolysaccharide and interactions with host MyD88 resulting in downregulation of intrinsic and extrinsic apoptotic responses to protect epithelial cells under highly inflammatory conditions. Our results reveal an important and previously undescribed role for B. breve, in positively modulating epithelial cell shedding outcomes via bacterial- and host-dependent factors, supporting the notion that manipulation of the microbiota affects intestinal disease outcomes. PMID:28123052

Bifidobacterium breve reduces apoptotic epithelial cell shedding in an exopolysaccharide and MyD88-dependent manner.

PubMed

Hughes, K R; Harnisch, L C; Alcon-Giner, C; Mitra, S; Wright, C J; Ketskemety, J; van Sinderen, D; Watson, A J M; Hall, L J

2017-01-01

Certain members of the microbiota genus Bifidobacterium are known to positively influence host well-being. Importantly, reduced bifidobacterial levels are associated with inflammatory bowel disease (IBD) patients, who also have impaired epithelial barrier function, including elevated rates of apoptotic extrusion of small intestinal epithelial cells (IECs) from villi-a process termed 'cell shedding'. Using a mouse model of pathological cell shedding, we show that mice receiving Bifidobacterium breve UCC2003 exhibit significantly reduced rates of small IEC shedding. Bifidobacterial-induced protection appears to be mediated by a specific bifidobacterial surface exopolysaccharide and interactions with host MyD88 resulting in downregulation of intrinsic and extrinsic apoptotic responses to protect epithelial cells under highly inflammatory conditions. Our results reveal an important and previously undescribed role for B. breve, in positively modulating epithelial cell shedding outcomes via bacterial- and host-dependent factors, supporting the notion that manipulation of the microbiota affects intestinal disease outcomes. © 2017 The Authors.

Fever-range hyperthermia improves the anti-apoptotic effect induced by low pH on human neutrophils promoting a proangiogenic profile.

PubMed

Díaz, Fernando Erra; Dantas, Ezequiel; Cabrera, Maia; Benítez, Constanza A; Delpino, María V; Duette, Gabriel; Rubione, Julia; Sanjuan, Norberto; Trevani, Analía S; Geffner, Jorge

2016-10-27

Neutrophils have the shortest lifespan among leukocytes and usually die via apoptosis, limiting their deleterious potential. However, this tightly regulated cell death program can be modulated by pathogen-associated molecular patterns (PAMPs), danger-associated molecular pattern (DAMPs), and inflammatory cytokines. We have previously reported that low pH, a hallmark of inflammatory processes and solid tumors, moderately delays neutrophil apoptosis. Here we show that fever-range hyperthermia accelerates the rate of neutrophil apoptosis at neutral pH but markedly increases neutrophil survival induced by low pH. Interestingly, an opposite effect was observed in lymphocytes; hyperthermia plus low pH prevents lymphocyte activation and promotes the death of lymphocytes and lymphoid cell lines. Analysis of the mechanisms through which hyperthermia plus low pH increased neutrophil survival revealed that hyperthermia further decreases cytosolic pH induced by extracellular acidosis. The fact that two Na + /H + exchanger inhibitors, 5-(N-ethyl-N-isopropyl) amiloride (EIPA) and amiloride, reproduced the effects induced by hyperthermia suggested that it prolongs neutrophil survival by inhibiting the Na + /H + antiporter. The neutrophil anti-apoptotic effect induced by PAMPs, DAMPs, and inflammatory cytokines usually leads to the preservation of the major neutrophil effector functions such as phagocytosis and reactive oxygen species (ROS) production. In contrast, our data revealed that the anti-apoptotic effect induced by low pH and hyperthermia induced a functional profile characterized by a low phagocytic activity, an impairment in ROS production and a high ability to suppress T-cell activation and to produce the angiogenic factors VEGF, IL-8, and the matrix metallopeptidase 9 (MMP-9). These results suggest that acting together fever and local acidosis might drive the differentiation of neutrophils into a profile able to promote both cancer progression and tissue repair during the late phase of inflammation, two processes that are strongly dependent on the local production of angiogenic factors by infiltrating immune cells.

Targeting Cellular Calcium Homeostasis to Prevent Cytokine-Mediated Beta Cell Death.

PubMed

Clark, Amy L; Kanekura, Kohsuke; Lavagnino, Zeno; Spears, Larry D; Abreu, Damien; Mahadevan, Jana; Yagi, Takuya; Semenkovich, Clay F; Piston, David W; Urano, Fumihiko

2017-07-17

Pro-inflammatory cytokines are important mediators of islet inflammation, leading to beta cell death in type 1 diabetes. Although alterations in both endoplasmic reticulum (ER) and cytosolic free calcium levels are known to play a role in cytokine-mediated beta cell death, there are currently no treatments targeting cellular calcium homeostasis to combat type 1 diabetes. Here we show that modulation of cellular calcium homeostasis can mitigate cytokine- and ER stress-mediated beta cell death. The calcium modulating compounds, dantrolene and sitagliptin, both prevent cytokine and ER stress-induced activation of the pro-apoptotic calcium-dependent enzyme, calpain, and partly suppress beta cell death in INS1E cells and human primary islets. These agents are also able to restore cytokine-mediated suppression of functional ER calcium release. In addition, sitagliptin preserves function of the ER calcium pump, sarco-endoplasmic reticulum Ca 2+ -ATPase (SERCA), and decreases levels of the pro-apoptotic protein thioredoxin-interacting protein (TXNIP). Supporting the role of TXNIP in cytokine-mediated cell death, knock down of TXNIP in INS1-E cells prevents cytokine-mediated beta cell death. Our findings demonstrate that modulation of dynamic cellular calcium homeostasis and TXNIP suppression present viable pharmacologic targets to prevent cytokine-mediated beta cell loss in diabetes.

Gemfibrozil pretreatment resulted in a sexually dimorphic outcome in the rat models of global cerebral ischemia-reperfusion via modulation of mitochondrial pro-survival and apoptotic cell death factors as well as MAPKs.

PubMed

Mohagheghi, Fatemeh; Ahmadiani, Abolhassan; Rahmani, Behrouz; Moradi, Fatemeh; Romond, Nathalie; Khalaj, Leila

2013-07-01

Inducers of mitochondrial biogenesis are widely under investigation for use in a novel therapeutic approach in neurodegenerative disorders. The ability of Gemfibrozil, a fibrate, is investigated for the first time to modulate mitochondrial pro-survival factors involved in the mitochondrial biogenesis signaling pathway, including peroxisome proliferator-activated receptor coactivator-1α (PGC-1α), nuclear respiratory factor (NRF-1), and mitochondrial transcription factor A (TFAM) in the brain. Gemfibozil is clinically administered to control hyperlipidemia. It secondarily prevents cardiovascular events such as cardiac arrest in susceptible patients. In this study, pretreatment of animals with gemfibrozil prior to ischemia-reperfusion (I/R) resulted in a sexually dimorphic outcome. While the expression of NRF-1 and TFAM were induced in gemfibrozil-pretreated met-estrous females, they were suppressed in males. Gemfibrozil also proved to be neuroprotective in met-estrous females, as it inhibited caspase-dependent apoptosis while in males it led to hippocampal neurodegeneration via activation of both the caspase-dependent and caspase-independent apoptosis. In the mitogen-activated protein kinase (MAPKs) pathway, gemfibrozil pretreatment induced the expression of extracellular signal-regulated kinases (ERK1/2) in met-estrous females and reduced it in males. These findings correlatively point to the sexual-dimorphic effects of gemfibrozil in global cerebral I/R context by affecting important factors involved in the mitochondrial biogenesis, MAPKs, and apoptotic cell death pathways.

Saponins from Tribulus terrestris L. protect human keratinocytes from UVB-induced damage.

PubMed

Sisto, Margherita; Lisi, Sabrina; D'Amore, Massimo; De Lucro, Raffaella; Carati, Davide; Castellana, Donatello; La Pesa, Velia; Zuccarello, Vincenzo; Lofrumento, Dario D

2012-12-05

Chronic exposure to solar UVB radiation damages skin, increasing the risk to develop cancer. Hence the identification of compounds with a photoprotective efficacy is essential. This study examined the role of saponins derived from Tribulus terrestris L. (TT) on the modulation of apoptosis in normal human keratinocytes (NHEK) exposed to physiological doses of UVB and to evaluate their antitumoral properties. In NHEK, TT saponins attenuate UVB-induced programmed cell death through inhibition of intrinsic apoptotic pathway. In squamous cell carcinomas (SCC) TT saponins do not make the malignant keratinocytes more resistant to UVB and determine an enhanced apoptotic response. The photoprotective effect of TT saponins is tightly correlated to the enhancement of NER genes expression and the block of UVB-mediated NF-κB activation. Collectively, our study shows experimental evidence that TT has a preventive efficacy against UVB-induced carcinogenesis and the molecular knowledge on the mechanisms through which TT saponins regulate cell death suggests great potential for TT to be developed into a new medicine for cancer patients. Copyright © 2012 Elsevier B.V. All rights reserved.

SIRT1 inhibition restores apoptotic sensitivity in p53-mutated human keratinocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herbert, Katharine J.; Cook, Anthony L., E-mail: Anthony.Cook@utas.edu.au; Snow, Elizabeth T., E-mail: elizabeth.snow@utas.edu.au

2014-06-15

Mutations to the p53 gene are common in UV-exposed keratinocytes and contribute to apoptotic resistance in skin cancer. P53-dependent activity is modulated, in part, by a complex, self-limiting feedback loop imposed by miR-34a-mediated regulation of the lysine deacetylase, SIRT1. Expression of numerous microRNAs is dysregulated in squamous and basal cell carcinomas; however the contribution of specific microRNAs to the pathogenesis of skin cancer remains untested. Through use of RNAi, miRNA target site blocking oligonucleotides and small molecule inhibitors, this study explored the influence of p53 mutational status, SIRT1 activity and miR-34a levels on apoptotic sensitivity in primary (NHEK) and p53-mutatedmore » (HaCaT) keratinocyte cell lines. SIRT1 and p53 are overexpressed in p53-mutated keratinocytes, whilst miR-34a levels are 90% less in HaCaT cells. HaCaTs have impaired responses to p53/SIRT1/miR-34a axis manipulation which enhanced survival during exposure to the chemotherapeutic agent, camptothecin. Inhibition of SIRT1 activity in this cell line increased p53 acetylation and doubled camptothecin-induced cell death. Our results demonstrate that p53 mutations increase apoptotic resistance in keratinocytes by interfering with miR-34a-mediated regulation of SIRT1 expression. Thus, SIRT1 inhibitors may have a therapeutic potential for overcoming apoptotic resistance during skin cancer treatment. - Highlights: • Impaired microRNA biogenesis promotes apoptotic resistance in HaCaT keratinocytes. • TP53 mutations suppress miR-34a-mediated regulation of SIRT1 expression. • SIRT1 inhibition increases p53 acetylation in HaCaTs, restoring apoptosis.« less

Neuroprotective Effect of Brassica oleracea Sprouts Crude Juice in a Cellular Model of Alzheimer's Disease

PubMed Central

Mattioli, Roberto; Costantino, Paolo; Baima, Simona; Punzi, Pasqualina; Giordano, Cesare; Pinto, Alessandro; Donini, Lorenzo Maria; d'Erme, Maria

2015-01-01

β-Amyloid peptide (Aβ) aberrant production and aggregation are major factors implicated in the pathogenesis of Alzheimer's disease (AD), causing neuronal death via oxidative stress. Several studies have highlighted the importance of polyphenolic antioxidant compounds in the treatment of AD, but complex food matrices, characterized by a different relative content of these phytochemicals, have been neglected. In the present study, we analyzed the protective effect on SH-SY5Y cells treated with the fragment Aβ 25–35 by two crude juices of broccoli sprouts containing different amounts of phenolic compounds as a result of different growth conditions. Both juices protected against Aβ-induced cytotoxicity and apoptotic cell death as evidenced by cell viability, nuclear chromatin condensation, and apoptotic body formation measurements. These effects were mediated by the modulation of the mitochondrial function and of the HSP70 gene transcription and expression. Furthermore, the juices upregulated the intracellular glutathione content and mRNA levels or activity of antioxidant enzymes such as heme oxygenase-1, thioredoxin, thioredoxin reductase, and NAD(P)H:quinone oxidoreductase 1 via activation of NF-E2-related factor 2 (Nrf2). Although the effects of the two juices were similar, the juice enriched in phenolic compounds showed a greater efficacy in inducing the activation of the Nrf2 signalling pathway. PMID:26180595

Modulation of Cellular Stress Response via the Erythropoietin/CD131 Heteroreceptor Complex in Mouse Mesenchymal-Derived Cells

PubMed Central

Bohr, Stefan; Patel, Suraj J; Vasko, Radovan; Shen, Keyue; Iracheta-Vellve, Arvin; Lee, Jungwoo; Bale, Shyam Sundhar; Chakraborty, Nilay; Brines, Michael; Cerami, Anthony; Berthiaume, Francois; Yarmush, Martin L

2014-01-01

Tissue protective properties of erythropoietin (EPO) have let to the discovery of an alternative EPO-signaling via an EPO-R/CD131 receptor complex which can now be specifically targeted through pharmaceutically designed short sequence peptides such as ARA290. However, little is still known about specific functions of alternative EPO-signaling in defined cell populations. In this study we investigated effects of signaling through EPO-R/CD131 complex on cellular stress responses and pro-inflammatory activation in different mesenchymal-derived phenotypes. We show that anti-apoptotic, anti-inflammatory effects of ARA290 and EPO coincide with the externalization of CD131 receptor component as an immediate response to cellular stress. In addition, alternative EPO-signaling strongly modulated transcriptional, translational or metabolic responses after stressor removal. Specifically, we saw that ARA290 was able overcome a TNFα-mediated inhibition of transcription factor activation related to cell stress responses, most notably of serum response factor (SRF), heat shock transcription factor protein 1 (HSF1) and activator protein 1 (AP1). We conclude that alternative EPO-signaling acts as a modulator of pro-inflammatory signaling pathways and likely plays a role in restoring tissue homeostasis. PMID:25373867

Establishment of a Transgenic Zebrafish Line for Superficial Skin Ablation and Functional Validation of Apoptosis Modulators In Vivo

PubMed Central

Chen, Chi-Fang; Chu, Che-Yu; Chen, Te-Hao; Lee, Shyh-Jye; Shen, Chia-Ning; Hsiao, Chung-Der

2011-01-01

Background Zebrafish skin is composed of enveloping and basal layers which form a first-line defense system against pathogens. Zebrafish epidermis contains ionocytes and mucous cells that aid secretion of acid/ions or mucous through skin. Previous studies demonstrated that fish skin is extremely sensitive to external stimuli. However, little is known about the molecular mechanisms that modulate skin cell apoptosis in zebrafish. Methodology/Principal Findings This study aimed to create a platform to conduct conditional skin ablation and determine if it is possible to attenuate apoptotic stimuli by overexpressing potential apoptosis modulating genes in the skin of live animals. A transgenic zebrafish line of Tg(krt4:NTR-hKikGR)cy17 (killer line), which can conditionally trigger apoptosis in superficial skin cells, was first established. When the killer line was incubated with the prodrug metrodinazole, the superficial skin displayed extensive apoptosis as judged by detection of massive TUNEL- and active caspase 3-positive signals. Great reductions in NTR-hKikGR+ fluorescent signals accompanied epidermal cell apoptosis. This indicated that NTR-hKikGR+ signal fluorescence can be utilized to evaluate apoptotic events in vivo. After removal of metrodinazole, the skin integrity progressively recovered and NTR-hKikGR+ fluorescent signals gradually restored. In contrast, either crossing the killer line with testing lines or transiently injecting the killer line with testing vectors that expressed human constitutive active Akt1, mouse constitutive active Stat3, or HPV16 E6 element displayed apoptosis-resistant phenotypes to cytotoxic metrodinazole as judged by the loss of reduction in NTR-hKikGR+ fluorescent signaling. Conclusion/Significance The killer/testing line binary system established in the current study demonstrates a nitroreductase/metrodinazole system that can be utilized to conditionally perform skin ablation in a real-time manner, and provides a valuable tool to visualize and quantify the anti-apoptotic potential of interesting target genes in vivo. The current work identifies a potential use for transgenic zebrafish as a high-throughput platform to validate potential apoptosis modulators in vivo. PMID:21655190

c-FLIP is involved in erythropoietin-mediated protection of erythroid-differentiated cells from TNF-alpha-induced apoptosis.

PubMed

Vittori, Daniela; Vota, Daiana; Callero, Mariana; Chamorro, María E; Nesse, Alcira

2010-05-04

The TNF-alpha (tumour necrosis factor) affects a wide range of biological activities, such as cell proliferation and apoptosis. Cell life or death responses to this cytokine might depend on cell conditions. This study focused on the modulation of factors that would affect the sensitivity of erythroid-differentiated cells to TNF-alpha. Hemin-differentiated K562 cells showed higher sensitivity to TNF-induced apoptosis than undifferentiated cells. At the same time, hemin-induced erythroid differentiation reduced c-FLIP (cellular FLICE-inhibitory protein) expression. However, this negative effect was prevented by prior treatment with Epo (erythropoietin), which allowed the cell line to maintain c-FLIP levels. On the other hand, erythroid-differentiated UT-7 cells - dependent on Epo for survival - showed resistance to TNF-alpha pro-apoptotic action. Only after the inhibition of PI3K (phosphatidylinositol-3 kinase)-mediated pathways, which was accompanied by negative c-FLIP modulation and increased erythroid differentiation, were UT-7 cells sensitive to TNF-alpha-triggered apoptosis. In summary, erythroid differentiation might deregulate the balance between growth promotion and death signals induced by TNF-alpha, depending on cell type and environmental conditions. The role of c-FLIP seemed to be critical in the protection of erythroid-differentiated cells from apoptosis or in the determination of their sensitivity to TNF-mediated programmed cell death. Epo, which for the first time was found to be involved in the prevention of c-FLIP down-regulation, proved to have an anti-apoptotic effect against the pro-inflammatory factor. The identification of signals related to cell life/death switching would have significant implications in the control of proliferative diseases and would contribute to the understanding of mechanisms underlying the anaemia associated with inflammatory processes.

4-aminopyridine, a Kv channel antagonist, prevents apoptosis of rat cerebellar granule neurons.

PubMed

Hu, Chang-Long; Liu, Zheng; Zeng, Xi-Min; Liu, Zi-Qiang; Chen, Xian-Hua; Zhang, Zhi-Hong; Mei, Yan-Ai

2006-09-01

Compelling evidence indicates that excessive potassium (K+) efflux and intracellular K+ depletion are the key early steps in apoptosis. Previously, we reported that apoptosis of cerebellar granule neurons induced by incubation in low-K+ (5 mM) and serum-free medium was associated with an increase in A-type transient inactivation of K+ channel current (IA) amplitude and modulation of channels' gating properties. Here, we showed that a classic K+ channel blocker, 4-aminopyradine (4-AP), significantly inhibited IA amplitude in a concentration-dependent manner (reduction of current by 10 microM and 10 mM 4-AP was 11.4+/-1.3% and 72.2+/-3.3%, respectively). Moreover, 4-AP modified the steady-state activation and inactivation kinetics of IA channels, such that the activation and inactivation curves were shifted to the right about 20 mV and 17 mV, respectively. Fluorescence staining showed that 4-AP dramatically increased the viability of cells undergoing apoptosis in a dose-dependent manner. That is, while 5 mM 4-AP was present, cell viability was 84.9+/-5.2%. Consistent with the cell viability analysis, internucleosomal DNA fragmentation by gel electrophoresis analysis showed that 5 mM 4-AP also protected against neuronal apoptosis. Furthermore, 4-AP significantly inhibited cytochrome c release and caspase-3 activity induced by low-K+/serum-free incubation. Finally, current-clamp analysis indicated that 5 mM 4-AP did not significantly depolarize the membrane potential. These results suggest that 4-AP has robust neuroprotective effects on apoptotic granule cells. The neuroprotective effect of 4-AP is likely not due to membrane depolarization, but rather that 4-AP may modulate the gating properties of IA channels in an anti-apoptotic manner.

CM363, a novel naphthoquinone derivative which acts as multikinase modulator and overcomes imatinib resistance in chronic myelogenous leukemia

PubMed Central

Díaz-Chico, Juan Carlos; McNaughton-Smith, Grant; Jiménez-Alonso, Sandra; Hueso-Falcón, Idaira; Montero, Juan Carlos; Blanco, Raquel; León, Javier; Rodríguez-González, Germán; Estévez-Braun, Ana; Pandiella, Atanasio; Díaz-Chico, Bonifacio Nicolás; Fernández-Pérez, Leandro

2017-01-01

Human Chronic Myelogenous Leukemia (CML) is a hematological stem cell disorder which is associated with activation of Bcr-Abl-Stat5 oncogenic pathway. Direct Bcr-Abl inhibitors are initially successful for the treatment of CML but over time many patients develop drug resistance. In the present study, the effects of CM363, a novel naphthoquinone (NPQ) derivative, were evaluated on human CML-derived K562 cells. CM363 revealed an effective cell growth inhibition (IC50 = 0.7 ± 0.5 μM) by inducing cancer cells to undergo cell cycle arrest and apoptosis. CM363 caused a dose- and time-dependent reduction of cells in G0/G1 and G2/M phases. This cell cycle arrest was associated with increased levels of cyclin E, pChk1 and pChk2 whereas CM363 downregulated cyclin B, cyclin D3, p27, pRB, Wee1, and BUBR1. CM363 increased the double-strand DNA break marker γH2AX. CM363 caused a time-dependent increase of annexin V-positive cells, DNA fragmentation and increased number of apoptotic nuclei. CM363 triggered the mitochondrial apoptotic pathway as reflected by a release of cytochrome C from mitochondria and induction of the cleavage of caspase-3 and -9, and PARP. CM363 showed multikinase modulatory effects through an early increased JNK phosphorylation followed by inhibition of pY-Bcrl-Abl and pY-Stat5. CM363 worked synergistically with imatinib to inhibit cell viability and maintained its activity in imatinib-resistant cells. Finally, CM363 (10 mg/Kg) suppressed the growth of K562 xenograft tumors in athymic mice. In summary, CM363 is a novel multikinase modulator that offers advantages to circumvent imanitib resistance and might be therapeutically effective in Bcrl-Abl-Stat5 related malignancies. PMID:27557509

CM363, a novel naphthoquinone derivative which acts as multikinase modulator and overcomes imatinib resistance in chronic myelogenous leukemia.

PubMed

Guerra, Borja; Martín-Rodríguez, Patricia; Díaz-Chico, Juan Carlos; McNaughton-Smith, Grant; Jiménez-Alonso, Sandra; Hueso-Falcón, Idaira; Montero, Juan Carlos; Blanco, Raquel; León, Javier; Rodríguez-González, Germán; Estévez-Braun, Ana; Pandiella, Atanasio; Díaz-Chico, Bonifacio Nicolás; Fernández-Pérez, Leandro

2017-05-02

Human Chronic Myelogenous Leukemia (CML) is a hematological stem cell disorder which is associated with activation of Bcr-Abl-Stat5 oncogenic pathway. Direct Bcr-Abl inhibitors are initially successful for the treatment of CML but over time many patients develop drug resistance. In the present study, the effects of CM363, a novel naphthoquinone (NPQ) derivative, were evaluated on human CML-derived K562 cells. CM363 revealed an effective cell growth inhibition (IC50 = 0.7 ± 0.5 μM) by inducing cancer cells to undergo cell cycle arrest and apoptosis. CM363 caused a dose- and time-dependent reduction of cells in G0/G1 and G2/M phases. This cell cycle arrest was associated with increased levels of cyclin E, pChk1 and pChk2 whereas CM363 downregulated cyclin B, cyclin D3, p27, pRB, Wee1, and BUBR1. CM363 increased the double-strand DNA break marker γH2AX. CM363 caused a time-dependent increase of annexin V-positive cells, DNA fragmentation and increased number of apoptotic nuclei. CM363 triggered the mitochondrial apoptotic pathway as reflected by a release of cytochrome C from mitochondria and induction of the cleavage of caspase-3 and -9, and PARP. CM363 showed multikinase modulatory effects through an early increased JNK phosphorylation followed by inhibition of pY-Bcrl-Abl and pY-Stat5. CM363 worked synergistically with imatinib to inhibit cell viability and maintained its activity in imatinib-resistant cells. Finally, CM363 (10 mg/Kg) suppressed the growth of K562 xenograft tumors in athymic mice. In summary, CM363 is a novel multikinase modulator that offers advantages to circumvent imanitib resistance and might be therapeutically effective in Bcrl-Abl-Stat5 related malignancies.

Modulation of hexavalent chromium-induced genotoxic damage in peripheral blood of mice by epigallocatechin-3-gallate (EGCG) and its relationship to the apoptotic activity.

PubMed

García-Rodríguez, María Del Carmen; Montaño-Rodríguez, Ana Rosa; Altamirano-Lozano, Mario Agustín

2016-01-01

This study was conducted to investigate the relationship between modulation of genotoxic damage and apoptotic activity in Hsd:ICR male mice treated with (-)-epigallocatechin-3-gallate (EGCG) and hexavalent chromium [Cr(VI)]. Four groups of 5 mice each were treated with (i) control vehicle only, (ii) EGCG (10 mg/kg) by gavage, (iii) Cr(VI) (20 mg/kg of CrO3) intraperitoneally (ip), and (iv) EGCG in addition to CrO3 (EGCG-CrO3). Genotoxic damage was evaluated by examining presence of micronucleated polychromatic erythrocytes (MN-PCE) obtained from peripheral blood of the caudal vein at 0, 24, 48, and 72 h after treatment. Induction of apoptosis and cell viability were assessed by differential acridine orange/ethidium bromide (AO/EB) staining. EGCG treatment produced no significant changes in frequency of MN-PCE. However, CrO3 treatment significantly increased number of MN-PCE at 24 and 48 h post injection. Treatment with EGCG prior to CrO3 injection decreased number of MN-PCE compared to CrO3 alone. The MN-PCE reduction was greater than when EGCG was administered ip. The frequency of early apoptotic cells was elevated at 48 h following EGCG, CrO3, or EGCG-CrO3 exposure, with highest levels observed in the combined treatment group, while the frequencies of late apoptotic cells and necrotic cells were increased only in EGCG-CrO3 exposure. Our findings support the view that EGCG is protective against genotoxic damage induced by Cr(VI) and that apoptosis may contribute to elimination of DNA-damaged cells (MN-PCE) when EGCG was administered prior to CrO3. Further, it was found that the route of administration of EGCG plays an important role in protection against CrO3-induced genotoxic damage.

Discovery of (4-bromophenyl)(3-hydroxy-4-methoxyphenyl)methanone through upregulating hTERT induces cell apoptosis and ERS

PubMed Central

Cheng, Xiu; Shi, Jing Bo; Liu, Hao; Chen, Liu Zeng; Wang, Yang; Tang, Wen Jian; Liu, Xin Hua

2017-01-01

Dominant-negative mutants of telomerase hTERT were demonstrated to have selective effects in tumor cells. However, no any effective and highly selective hTERT inhibitor has been developed so far. We focused on developing new hTERT modulators and synthesized a small molecular compound, named (4-bromophenyl)(3-hydroxy-4-methoxyphenyl)methanone. Our in vitro studies found that title compound showed high inhibitory activity against telomerase, had high antiproliferative capacity on SMMC-7721 cells with IC50 value 88 nm, and had no obvious toxic effect on human normal hepatocyte cells with IC50 value 10 μM. Our in vivo studies showed that this compound significantly inhibited tumor growth in xenograft tumor models. The further molecular mechanisms of title compound inhibition SMMC-7721 cell proliferation by modulating hTERT were explored; the results showed that endoplasmic reticulum stress (ERS) through ER over response (EOR) activates the expression of hTERT, and then induces ERS, which is believed to be intricately associated with oxidative stress and mitochondrial dysfunction, resulting in apoptotic cell death, thereby modulating the expression of downstream signaling molecules including CHOP (CAAT/enhancer-binding protein homologous protein)) and mitochondrion pathway of apoptosis, leading to inhibition of cell proliferation. PMID:28837145

Molecular characterization and immunological roles of avian IL-22 and its soluble receptor IL-22 binding protein

USDA-ARS?s Scientific Manuscript database

As a member of the interleukin (IL)-10 family, IL-22 is an important mediator in modulating tissue responses during inflammation. Through activation of STAT3-signaling cascades, IL-22 induces proliferative and anti-apoptotic pathways, as well as antimicrobial peptides (AMPs), that help prevent tissu...

Facilitation of apoptosis by cyclosporins A and H, but not FK506 in mouse bronchial eosinophils.

PubMed

Kitagaki, K; Nagai, H; Hayashi, S; Totsuka, T

1997-10-22

This study was undertaken to clarify whether or not binding to cyclophilin is a prerequisite for cyclosporin A-induced modulation of apoptotic cell death in eosinophils. Eosinophils were isolated from bronchoalveolar lavage fluid of mice challenged with inhaled allergen after sensitization. Apoptosis was determined by analysing the DNA content. At 72 h, 99% of the cells had died without addition of cytokines, whereas 55-60% of the cells survived in the presence of 10 U/ml recombinant murine interleukin 5 or recombinant murine granulocyte macrophage-colony stimulation factor (GM-CSF). Apoptotic cell death at 72 h in the presence of 10 U/ml interleukin 5 was increased by addition of cyclosporin H, an analogue of cyclosporin A without cyclophilin binding activity, in a concentration-dependent (0.3 to 3 microM) manner. The increase in apoptosis elicited by cyclosporin A and cyclosporin H took place also in the presence of 10 U/ml GM-CSF but to a lesser extent. There was a significant augmentation of apoptosis in eosinophils cultured in the presence of each cytokine for 72 h or longer. Tacrolimus (FK506) failed to augment apoptotic cell death. Thus, it is unlikely that binding of cyclosporin A to cyclophilin accounts for the increased apoptosis induced by cyclosporin A and its analogue in eosinophils. The increase in apoptosis induced by cyclosporin A, but not FK506, in activated eosinophils from the airways may be attributed to the anti-asthmatic effects of cyclosporin A.

Dengue Virus Modulates the Unfolded Protein Response in a Time-dependent Manner*

PubMed Central

Peña, José; Harris, Eva

2011-01-01

Flaviviruses, such as dengue virus (DENV), depend on the host endoplasmic reticulum for translation, replication, and packaging of their genomes. Here we report that DENV-2 infection modulates the unfolded protein response in a time-dependent manner. We show that early DENV-2 infection triggers and then suppresses PERK-mediated eIF2α phosphorylation and that in mid and late DENV-2 infection, the IRE1-XBP1 and ATF6 pathways are activated, respectively. Activation of IRE1-XBP1 correlated with induction of downstream targets GRP78, CHOP, and GADD34. Furthermore, induction of CHOP did not induce apoptotic markers, such as suppression of anti-apoptotic protein Bcl-2, activation of caspase-9 or caspase-3, and cleavage of poly(ADP-ribose) polymerase. Finally, we show that DENV-2 replication is affected in PERK−/− and IRE1−/− mouse embryo fibroblasts when compared with wild-type mouse embryo fibroblasts. These results demonstrate that time-dependent activation of the unfolded protein response by DENV-2 can override inhibition of translation, prevent apoptosis, and prolong the viral life cycle. PMID:21385877

ATP depletion inhibits glucocorticoid-induced thymocyte apoptosis.

PubMed Central

Stefanelli, C; Bonavita, F; Stanic', I; Farruggia, G; Falcieri, E; Robuffo, I; Pignatti, C; Muscari, C; Rossoni, C; Guarnieri, C; Caldarera, C M

1997-01-01

In quiescent thymocytes, mitochondrial de-energization was not correlated to apoptotic death. In fact, thymocytes treated with oligomycin, a highly specific inhibitor of ATP synthase, alone or with atractyloside to block ATP translocation from the cytoplasm, were alive, even if their mitochondria were depolarized, as revealed by flow cytometry after Rhodamine 123 staining. Furthermore, oligomycin was a powerful inhibitor of apoptosis induced in rat thymocytes by dexamethasone and, to a lesser extent, by the calcium ionophore A23187 and etoposide, but was without effect when apoptosis was induced by staurosporine, and increased cell death in mitogen-treated thymocytes. The inhibition of apoptosis was confirmed by morphological criteria, inhibition of inter-nucleosomal DNA fragmentation and inhibition of the loss of membrane integrity. The anti-apoptotic effect of oligomycin in cells treated with A23187 or etoposide was correlated to the inhibition of protein synthesis, while inhibition of apoptosis induced by dexamethasone, already evident at an oligomycin concentration of 10 ng/ml, was instead strictly correlated to the effect exerted on the cellular ATP level. Thymocyte apoptosis triggered by dexamethasone was blocked or delayed by inhibitors of respiratory-chain uncouplers, inhibitors of ATP synthase and antioxidants: a lasting protection from dexamethasone-induced apoptosis was always correlated to a drastic and rapid reduction in ATP level (31-35% of control), while a delay in the death process was characterized by a moderate decrease in ATP (73-82% of control). Oligomycin inhibited the specific binding of radioactive corticosteroid to thymocyte nuclei, confirming the inhibitory effect of ATP depletion on glucocorticoid binding and suggesting that ATP depletion is a common mediator of the anti-apoptotic action of different effectors in glucocorticoid-induced apoptosis. In conclusion, the reported data indicate that ATP may act as a cellular modulator of some forms of apoptosis, depending on the death trigger, and that in quiescent cells the de-energization of mitochondria is not necessarily linked to apoptosis. PMID:9148768

Efficient antitumor effect of co-drug-loaded nanoparticles with gelatin hydrogel by local implantation

PubMed Central

Zhang, Hao; Tian, Yong; Zhu, Zhenshu; Xu, Huae; Li, Xiaolin; Zheng, Donghui; Sun, Weihao

2016-01-01

Tetrandrine (Tet) could enhance the antitumor effect of Paclitaxel (Ptx) by increasing intracellular Reactive Oxygen Species (ROS) levels, which leads to the possibility of co-delivery of both drugs for synergistic antitumor effect. In the current study, we reported an efficient, local therapeutic strategy employing effective Tet and Ptx delivery with a nanoparticle-loaded gelatin system. Tet- and Ptx co-loaded mPEG-PCL nanoparticles (P/T-NPs) were encapsulated into the physically cross-linked gelatin hydrogel and then implanted on the tumor site for continuous drug release. The drug-loaded gelatin hydrogel underwent a phase change when the temperature slowly increased. In vitro study showed that Tet/Ptx-loaded PEG-b-PCL nanoparticles encapsulated within a gelatin hydrogel (P/T-NPs-Gelatin) inhibited the growth and invasive ability of BGC-823 cells more effectively than the combination of free drugs or P/T-NPs. In vivo study validated the therapeutic potential of P/T-NPs-Gelatin. P/T-NPs-Gelatin significantly inhibited the activation of p-Akt and the downstream anti-apoptotic Bcl-2 protein and also inducing the activation of pro-apoptotic Bax protein. Moreover, the molecular-modulating effect of P/T-NPs-Gelatin on related proteins varied slightly under the influence of NAC, which was supported by the observations of the tumor volumes and weights. Based on these findings, local implantation of P/T-NPs-Gelatin may be a promising therapeutic strategy for the treatment of gastric cancer. PMID:27226240

Designing Inhibitors of Cytochrome c/Cardiolipin Peroxidase Complexes: Mitochondria-Targeted Imidazole-Substituted Fatty Acids

PubMed Central

Jiang, Jianfei; Bakan, Ahmet; Kapralov, Alexandr A.; Silva, K. Ishara; Huang, Zhentai; Amoscato, Andrew A.; Peterson, James; Garapati, Venkata Krishna; Saxena, Sunil; Bayir, Hülya; Atkinson, Jeffrey; Bahar, Ivet; Kagan, Valerian E.

2014-01-01

Mitochondria have emerged as the major regulatory platform responsible for coordination of numerous metabolic reactions as well as cell death processes, whereby the execution of intrinsic apoptosis includes the production of reactive oxygen species fueling oxidation of cardiolipin (CL) catalyzed by cytochrome (cyt) c. As this oxidation occurs within the peroxidase complex of cyt c with CL, the latter represents a promising target for the discovery and design of drugs with anti-apoptotic mechanism of action. In this work, we designed and synthesized a new group of mitochondria-targeted imidazole-substituted analogues of stearic acid TPP-n-ISA with different positions of the attached imidazole group on the fatty acid (n=6, 8, 10, 13 and 14). By using a combination of absorption spectroscopy and EPR protocols (continuous wave electron paramagnetic resonance, and electron spin echo envelope modulation) we demonstrated that TPP-n-ISA indeed were able to potently suppress CL induced structural re-arrangements in cyt c paving the way to its peroxidase competence. TPP-n-ISA analogues preserved the low spin hexa-coordinated heme iron state in cyt c/CL complexes whereby TPP-6-ISA displayed a significantly more effective preservation pattern than TPP-14-ISA. Elucidation of these intermolecular stabilization mechanisms of cyt c identified TPP-6-ISA as an effective inhibitor of the peroxidase function of cyt c/CL complexes with a significant anti-apoptotic potential realized in mouse embryonic cells exposed to ionizing irradiation. These experimental findings were detailed and supported by all atom molecular dynamics simulations. Based on the experimental data and computations predictions, we identified TPP-6-ISA as a candidate drug with optimized anti-apoptotic potency. PMID:24631490

Additive Renoprotection by Pioglitazone and Fenofibrate against Inflammatory, Oxidative and Apoptotic Manifestations of Cisplatin Nephrotoxicity: Modulation by PPARs

PubMed Central

Helmy, Mai M.; Helmy, Maged W.; El-Mas, Mahmoud M.

2015-01-01

Nephrotoxicity is a major side effect for the antineoplastic drug cisplatin. Here, we employed pharmacological, biochemical, and molecular studies to investigate the role of peroxisome proliferator-activated receptors (PPARs) in cisplatin nephrotoxicity. Rats were treated with a single i.p. dose of cisplatin (5 mg/kg) alone or combined with pioglitazone (PPARγ agonist), fenofibrate (PPARα agonist), pioglitazone plus fenofibrate, or thalidomide (Tumor necrosis factor-α inhibitor; TNF-α). Cisplatin nephrotoxicity was evidenced by rises in renal indices of functional (blood urea nitrogen, BUN, and creatinine), inflammatory (TNF-α, interleukin 6, IL-6), oxidative (increased malondialdehyde, MDA, and decreased superoxide dismutase, SOD and nitric oxide metabolites, NOx), apoptotic (caspase 3), and histological (glomerular atrophy, acute tubular necrosis and vacuolation) profiles. Cisplatin effects were partly abolished upon concurrent exposure to pioglitazone, fenofibrate, or thalidomide; more renoprotection was observed in rats treated with pioglitazaone plus fenofibrate. Immunostaining showed that renal expressions of PPARα and PPARγ were reduced by cisplatin and restored to vehicle-treated values after simultaneous treatment with pioglitazone or fenofibrate. Fenofibrate or pioglitazone renoprotection remained unaltered after concurrent blockade of PPARα (GW6471) and PPARγ (GW9662), respectively. To complement the rat studies, we also report that in human embryonic kidney cells (HEK293 cells), increases caused by cisplatin in inflammatory, apoptotic, and oxidative biomarkers were (i) partly improved after exposure to pioglitazone, fenofibrate, or thalidomide, and (ii) completely disappeared in cells treated with a combination of all three drugs. These data establish that the combined use of pioglitazone and fenofibrate additively improved manifestations of cisplatin nephrotoxicity through perhaps GW6471/GW9662-insensitive mechanisms. PMID:26536032

NF-{kappa}B inhibition is involved in tobacco smoke-induced apoptosis in the lungs of rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhong Caiyun; Zhou Yamei; Pinkerton, Kent E.

2008-07-15

Apoptosis is a vital mechanism for the regulation of cell turnover and plays a critical role in tissue homeostasis and development of many disease processes. Previous studies have demonstrated the apoptotic effect of tobacco smoke; however, the molecular mechanisms by which tobacco smoke triggers apoptosis remain unclear. In the present study we investigated the effects of tobacco smoke on the induction of apoptosis in the lungs of rats and modulation of nuclear factor-kappa B (NF-{kappa}B) in this process. Exposure of rats to 80 mg/m{sup 3} tobacco smoke significantly induced apoptosis in the lungs. Tobacco smoke resulted in inhibition of NF-{kappa}Bmore » activity, noted by suppression of inhibitor of {kappa}B (I{kappa}B) kinase (IKK), accumulation of I{kappa}B{alpha}, decrease of NF-{kappa}B DNA binding activity, and downregulation of NF-{kappa}B-dependent anti-apoptotic proteins, including Bcl-2, Bcl-xl, and inhibitors of apoptosis. Initiator caspases for the death receptor pathway (caspase 8) and the mitochondrial pathway (caspase 9) as well as effector caspase 3 were activated following tobacco smoke exposure. Tobacco smoke exposure did not alter the levels of p53 and Bax proteins. These findings suggest the role of NF-{kappa}B pathway in tobacco smoke-induced apoptosis.« less

Topical Treatment of Hair Loss with Formononetin by Modulating Apoptosis.

PubMed

Kim, Mi Hye; Choi, You Yeon; Lee, Ji Eun; Kim, Kyuseok; Yang, Woong Mo

2016-01-01

Formononetin is one of the main components of red clover plants and its role on hair regrowth against hair loss has not been established yet. In the present study, we assessed the potential effects of formononetin on alopecia, along with impaired hair cycles by induction of apoptosis-regression.Depilated C57BL/6 mice were used for monitoring the hair cycles. Formononetin (1 and 100 µM) was topically treated to the dorsal skin for 14 days. Topical formononetin treatment induced miniaturized hair follicles to recover to normal sizes. Tapering hair shaft began to grow newly, emerging from the hair follicles by formononetin. In addition, formononetin inhibited the activation of caspase-8 and decreased the procaspase-9 expression. As a result of formononetin treatment, anti-apoptotic Bcl-2 was up-regulated, whereas pro-apoptotic Bax and p53 were down-regulated, resulting in a decrease of caspase-3 activation. Formononetin showed the obvious inhibition of apoptosis under terminal deoxynucleotidyl transferase dUTP nick end labeling staining thereafter.Taken together, our findings demonstrate that formononetin exerted the hair regrowth effect on hair loss, in which the underlying mechanisms were associated with Fas/Fas L-induced caspase activation, thus inhibiting apoptosis. Georg Thieme Verlag KG Stuttgart · New York.

δ- and γ-tocotrienols induce classical ultrastructural apoptotic changes in human T lymphoblastic leukemic cells.

PubMed

Wong, Rebecca S Y; Radhakrishnan, Ammu K; Ibrahim, Tengku Azmi Tengku; Cheong, Soon-Keng

2012-06-01

Tocotrienols are isomers of the vitamin E family, which have been reported to exert cytotoxic effects in various cancer cells. Although there have been some reports on the effects of tocotrienols in leukemic cells, ultrastructural evidence of tocotrienol-induced apoptotic cell death in leukemic cells is lacking. The present study investigated the effects of three isomers of tocotrienols (alpha, delta, and gamma) on a human T lymphoblastic leukemic cell line (CEM-SS). Cell viability assays showed that all three isomers had cytotoxic effects (p < 0.05) on CEM-SS cells with delta-tocotrienol being the most potent. Transmission electron microscopy showed that the cytotoxic effects by delta- and gamma-tocotrienols were through the induction of an apoptotic pathway as demonstrated by the classical ultrastructural apoptotic changes characterized by peripheral nuclear chromatin condensation and nuclear fragmentation. These findings were confirmed biochemically by the demonstration of phosphatidylserine externalization via flow cytometry analysis. This is the first study showing classical ultrastructural apoptotic changes induced by delta- and gamma-tocotrienols in human T lymphoblastic leukemic cells.

Wheatgrass-Derived Polysaccharide Has Antiinflammatory, Anti-Oxidative and Anti-Apoptotic Effects on LPS-Induced Hepatic Injury in Mice.

PubMed

Nepali, Sarmila; Ki, Hyeon-Hui; Lee, Ji-Hyun; Lee, Hoon-Yeon; Kim, Dae-Ki; Lee, Young-Mi

2017-07-01

Hepatic injury occurs frequently during sepsis, and polysaccharides isolated from plants have been reported to have antiinflammatory and antioxidant effects in various models. However, the effect of wheatgrass-derived polysaccharide (WGP) has not been previously studied. In the present study, we investigated the effect of WGP on lipopolysaccharide (LPS)-induced hepatic injury in mice. Mice were pre-treated with WGP (100 or 200 mg/kg daily for 2 days) and then challenged with LPS (1 mg/kg, intraperitoneal), and sacrificed after 12 h. Wheatgrass-derived polysaccharide decreased serum aminotransferase levels and histological changes as compared with LPS-challenged mice. Wheatgrass-derived polysaccharide also significantly inhibited LPS-induced pro-inflammatory cytokine up-regulation and improved the oxidative status of liver tissues. Furthermore, these effects were found to be mediated by the suppression of the transcriptional activity of nuclear factor-kappa B (NF-κB), due to inhibitions of transforming growth factor beta (TGF-β)-activated kinase (TAK)-1 phosphorylation and inhibition of kappa B (IκB)-α degradation. In addition, WGP inhibited the activations of mitogen-activated protein kinases (MAPKs). Wheatgrass-derived polysaccharide also attenuated hepatic cell death by modulating caspase-3 and apoptosis associated mitochondrial proteins, such as, B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax). Taken together, WGP possesses antiinflammatory, anti-oxidant and anti-apoptotic activity and ameliorates LPS-induced liver injury in mice. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Baicalein antagonizes rotenone-induced apoptosis in dopaminergic SH-SY5Y cells related to Parkinsonism.

PubMed

Song, Ju-Xian; Choi, Mandy Yuen-Man; Wong, Kavin Chun-Kit; Chung, Winkie Wing-Yan; Sze, Stephen Cho-Wing; Ng, Tzi-Bun; Zhang, Kalin Yan-Bo

2012-01-21

Two active compounds, baicalein and its glycoside baicalin were found in the dried root of Scutellaria baicalensis Georgi, and reported to be neuroprotective in vitro and in vivo. This study aims to evaluate the protective effects of baicalein on the rotenone-induced apoptosis in dopaminergic SH-SY5Y cells related to parkinsonism. Cell viability and cytotoxicity were determined by MTT assay. The degree of nuclear apoptosis was evaluated with a fluorescent DNA-binding probe Hoechst 33258. The production of reactive oxidative species (ROS) and loss of mitochondrial membrane potential (ΔΨm) were determined by fluorescent staining with DCFH-DA and Rhodanmine 123, respectively. The expression of Bax, Bcl-2, cleaved caspase-3 and phosphorylated ERK1/2 was determined by the Western blots. Baicalein significantly increased viability and decreased rotenone-induced death of SH-SY5Y cells in a dose-dependent manner. Pre- and subsequent co-treatment with baicalein preserved the cell morphology and attenuated the nuclear apoptotic characteristics triggered by rotenone. Baicalein antagonized rotenone-induced overproduction of ROS, loss of ΔΨm, the increased expression of Bax, cleaved caspase-3 and phosphorylated ERK1/2 and the decreased expression of Bcl-2. The antioxidative effect, mitochondrial protection and modulation of anti-and pro-apoptotic proteins are related to the neuroprotective effects of baicalein against rotenone induced cell death in SH-SY5Y cells.

Long-term treatment of anterior pituitary cells with nitric oxide induces programmed cell death.

PubMed

Velardez, Miguel Omar; Poliandri, Ariel Hernán; Cabilla, Jimena Paula; Bodo, Cristian Carlos Armando; Machiavelli, Leticia Inés; Duvilanski, Beatriz Haydeé

2004-04-01

Nitric oxide (NO) plays a complex role in modulating programmed cell death. It can either protect the cell from apoptotic death or mediate apoptosis, depending on its concentration and the cell type and/or status. In this study, we demonstrate that long-term exposition to NO induces cell death of anterior pituitary cells from Wistar female rats. DETA NONOate (Z)-1-[2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate, 1 mm], a NO donor that releases NO for an extended period of time, decreased cellular viability and prolactin release from primary cultures of anterior pituitary cells. Morphological studies showed an increase in the number of cells with chromatin condensation and nuclear fragmentation at 24 and 48 h after DETA/NO exposure. DNA internucleosomal fragmentation was also observed at the same time. Reversibility of the NO effect on cellular viability and prolactin release was observed only when the cells were incubated with DETA/NO for less than 6 h. Most apoptotic cells were immunopositive for prolactin, suggesting a high susceptibility of lactotrophs to the effect of NO. The cytotoxic effect of NO is dependent of caspase-9 and caspase-3, but seems to be independent of oxidative stress or nitrosative stress. Our results show that the exposition of anterior pituitary cells to NO for long periods induces programmed cell death of anterior pituitary cells.

Impaired phagocytosis of apoptotic cell material in serologically active clinically quiescent patients with systemic lupus erythematosis.

PubMed

Huang, Wen-Nan; Tso, Tim K; Wu, Hsiao-Chih; Yang, Hsiu-Fen; Tsay, Gregory J

2016-12-01

Serologically active clinically quiescent (SACQ) patients with systemic lupus erythematosus (SLE) account for 8-12% of all patients with SLE, but there is disagreement about whether such patients are indeed clinically stable. Patients with clinically active SLE have decreased macrophage function, although the status of SACQ patients with SLE is unclear. This study compared 18 patients who met the diagnostic criteria for SACQ SLE with 18 healthy volunteers with regard to the capability of macrophages to clear apoptotic bodies by use of a modified serum-free phagocytosis test. Macrophages that naturally differentiated from monocytes were used to engulf apoptotic cells developed from polymorphonuclear neutrophils. The results showed that macrophages from SACQ patients with SLE had less phagocytotic capability than those from healthy controls. The significant reduction of macrophage phagocytotic capability in these patients suggests the potential for disease recurrence. The use of a serum-free method confirmed the presence of intrinsic factors that modulate the decrease of macrophage function in SLE. © 2015 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

Disruption of chromosomal locus 1p36 differentially modulates TAp73 and ΔNp73 expression in follicular lymphoma

PubMed Central

Hassan, Hesham M.; Varney, Michelle L.; Jain, Smrati; Weisenburger, Dennis D.; Singh, Rakesh K.; Dave, Bhavana J.

2015-01-01

The TP73 gene is located at the chromosome 1p36 locus that is commonly disrupted or deleted in follicular lymphoma (FL) with poor prognosis. Therefore, we analyzed the expression of the pro-apoptotic TAp73 and anti-apoptotic ΔNp73 isoforms in FL cases with normal or abnormal 1p36. We observed a significant increase in ΔNp73 expression and ΔNp73:TAp73 ratio, lower expression of cleaved caspase-3 and a higher frequency of Ki-67 and PCNA positive cells in FL cases with abnormal 1p36. A negative correlation between the ΔNp73:TAp73 ratio and cleaved caspase-3 expression, and a positive correlation between ΔNp73 expression and Ki-67 or PCNA were observed. The expression of TAp73 and its pro-apoptotic transcriptional targets Bim, Puma, and Noxa were significantly lower in FL compared to reactive follicular hyperplasia. Together, our data demonstrates that 1p36 disruption is associated with increased ΔNp73 expression, decreased apoptosis and increased proliferation in FL. PMID:24660851

The crude extract of Corni Fructus induces apoptotic cell death through reactive oxygen species-modulated pathways in U-2 OS human osteosarcoma cells.

PubMed

Liao, Ching-Lung; Hsu, Shu-Chun; Yu, Chien-Chih; Yang, Jai-Sing; Tang, Nou-Ying; Wood, Wellington Gibson; Lin, Jaung-Geng; Chung, Jing-Gung

2014-09-01

Crude extract of Corni Fructus (CECF) has been used in Traditional Chinese medicine for the treatment of different diseases for hundreds of years. The purpose of this study was to investigate the cytotoxic effects of CECF on U-2 OS human osteosarcoma cells. Flow cytometry was used for measuring the percentage of viable cells, cell-cycle distribution, apoptotic cells in sub-G1 phase, reactive oxygen species (ROS), Ca(2+) levels, and mitochondrial membrane potential (ΔΨm ). Comet assay and 4'-6-diamidino-2-phenylindole staining were used for examining DNA damage and condensation. Western blotting was used to examine apoptosis-associated protein levels in U-2 OS cells after exposed to CECF. Immunostaining and confocal laser system microscope were used to examine protein translocation after CECF incubation. CECF decreased the percentage of viability, induced DNA damage and DNA condensation, G₀/G₁ arrest, and apoptosis in U-2 OS cells. CECF-stimulated activities of caspase-8, caspase-9, and caspase-3, ROS, and Ca(2+) production, decreased ΔΨm levels of in U-2 OS cells. CECF increased protein levels of caspase-3, caspase-9, Bax, cytochrome c, GRP78, AIF, ATF-6α, Fas, TRAIL, p21, p27, and p16 which were associated with cell-cycle arrest and apoptosis. These findings suggest that CECF triggers apoptosis in U-2 OS cells via ROS-modulated caspase-dependent and -independent pathways. Copyright © 2012 Wiley Periodicals, Inc., a Wiley company.

Intravenous infusion of apoptotic cells simultaneously with allogeneic hematopoietic grafts alters anti-donor humoral immune responses.

PubMed

Perruche, Sylvain; Kleinclauss, François; Bittencourt, Marcelo de Carvalho; Paris, Dominique; Tiberghien, Pierre; Saas, Philippe

2004-08-01

Intravenous infusion of apoptotic donor or third-party leukocytes simultaneously with an allogeneic donor bone marrow (BM) graft favors engraftment across major histocompatibility barriers. While verifying that such apoptotic cell infusion might not also be associated with antibody (Ab)-mediated allo-immune responses, we found, rather strikingly, that apoptotic cell infusion could in fact successfully prevent a humoral allo-immunization against a BM graft in mice. Indeed, among recipients having rejected their BM graft, prior apoptotic cell infusion was associated with a near absence of Ab-mediated allo-responses, while such an immunization was frequently observed in the absence of apoptotic cell infusion. This was also observed when infusing host apoptotic cells, thus showing that the prevention of immunization was linked to the apoptotic state of the cells rather than mediated by residual anti-recipient activity. In vivo anti-transforming growth factor-beta (TGF-beta) treatment resulted in the loss of this apoptotic cell infusion-associated protective effect on humoral allo-responses. Further studies will determine whether apoptotic cell infusion, in addition to hematopoietic graft facilitation might also contribute to preventing deleterious Ab-mediated allo-responses in various transplantation settings.

Endocannabinoids modulate apoptosis in endometriosis and adenomyosis.

PubMed

Bilgic, Elif; Guzel, Elif; Kose, Sevil; Aydin, Makbule Cisel; Karaismailoglu, Eda; Akar, Irem; Usubutun, Alp; Korkusuz, Petek

2017-06-01

Adenomyosis that is a form of endometriosis is the growth of ectopic endometrial tissue within the muscular wall of the uterus (myometrium), which may cause dysmenorrhea and infertility. Endocannabinoid mediated apoptotic mechanisms of endometriosis and adenomyosis are not known. We hypothesized that the down regulation of endocannabinoid receptors and/or alteration in their regulatory enzymes may have a direct role in the pathogenesis of endometriosis and adenomyosis through apoptosis. Endocannabinoid receptors CB1 and CB2, their synthesizing and catabolizing enzymes (FAAH, NAPE-PLD, DAGL, MAGL) and the apoptotic indexes were immunohistochemically assessed in endometriotic and adenomyotic tissues. Findings were compared to normal endometrium and myometrium. Endometrial adenocarcinoma (Ishikawa) and ovarian endometriosis cyst wall stromal (CRL-7566) cell lines were furthermore cultured with or without cannabinoid receptor agonists. The IC50 value for CB1 and CB2 receptor agonists was quantified. Cannabinoid agonists on cell death were investigated by Annexin-V/Propidium iodide labeling with flow cytometry. CB1 and CB2 receptor levels decreased in endometriotic and adenomyotic tissues compared to the control group (p=0,001 and p=0,001). FAAH, NAPE-PLD, MAGL and DAGL enzyme levels decreased in endometriotic and adenomyotic tissues compared to control (p=0,001, p=0,001, p=0,001 and p=0,002 respectively). Apoptotic cell indexes both in endometriotic and adenomyotic tissues also decreased significantly, compared to the control group (p=0,001 and p=0,001). CB1 and CB2 receptor agonist mediated dose dependent fast anti-proliferative and pro-apoptotic effects were detected in Ishikawa and ovarian endometriosis cyst wall stromal cell lines (CRL-7566). Endocannabinoids are suggested to increase apoptosis mechanisms in endometriosis and adenomyosis. CB1 and CB2 antagonists can be considered as potential medical therapeutic agents for endometriosis and adenomyosis. Copyright © 2017 Elsevier GmbH. All rights reserved.

Prospects of apoptotic cell-based therapies for transplantation and inflammatory diseases.

PubMed

Saas, Philippe; Kaminski, Sandra; Perruche, Sylvain

2013-10-01

Apoptotic cell removal or interactions of early-stage apoptotic cells with immune cells are associated with an immunomodulatory microenvironment that can be harnessed to exert therapeutic effects. While the involved immune mechanisms are still being deciphered, apoptotic cell infusion has been tested in different experimental models where inflammation is deregulated. This includes chronic and acute inflammatory disorders such as arthritis, contact hypersensitivity and acute myocardial infarction. Apoptotic cell infusion has also been used in transplantation settings to prevent or treat acute and chronic rejection, as well as to limit acute graft-versus-host disease associated with allogeneic hematopoietic cell transplantation. Here, we review the mechanisms involved in apoptotic cell-induced immunomodulation and data obtained in preclinical models of transplantation and inflammatory diseases.

Curcumin affects cell survival and cell volume regulation in human renal and intestinal cells

PubMed Central

Kössler, Sonja; Nofziger, Charity; Jakab, Martin; Dossena, Silvia; Paulmichl, Markus

2012-01-01

Curcumin (1,7-bis(4-hydroxy-3-methoxyphenyl)-1E,6E-heptadiene-3,5-dione or diferuloyl methane) is a polyphenol derived from the Curcuma longa plant, commonly known as turmeric. This substance has been used extensively in Ayurvedic medicine for centuries for its anti-oxidant, analgesic, anti-inflammatory and antiseptic activity. More recently curcumin has been found to possess anti-cancer properties linked to its pro-apoptotic and anti-proliferative actions. The underlying mechanisms of these diverse effects are complex, not fully elucidated and subject of intense scientific debate. Despite increasing evidence indicating that different cation channels can be a molecular target for curcumin, very little is known about the effect of curcumin on chloride channels. Since, (i) the molecular structure of curcumin indicates that the substance could potentially interact with chloride channels, (ii) chloride channels play a role during the apoptotic process and regulation of the cell volume, and (iii) apoptosis is a well known effect of curcumin, we set out to investigate whether or not curcumin could (i) exert a modulatory effect (direct or indirect) on the swelling activated chloride current IClswell in a human cell system, therefore (ii) affect cell volume regulation and (iii) ultimately modulate cell survival. The IClswell channels, which are essential for regulating the cell volume after swelling, are also known to be activated under isotonic conditions as an early event in the apoptotic process. Here we show that long-term exposure of a human kidney cell line to extracellular 0.1–10 μM curcumin modulates IClswell in a dose-dependent manner (0.1 μM curcumin is ineffective, 0.5–5.0 μM curcumin increase, while 10 μM curcumin decrease the current), and short-term exposure to micromolar concentrations of curcumin does not affect IClswell neither if applied from the extracellular nor from the intracellular side – therefore, a direct effect of curcumin on IClswell can be ruled out. Furthermore, we show that curcumin exposure induces apoptosis in human kidney cells, and at a concentration of 5.0–10 μM induces the appearance of a sub-population of cells with a dramatically increased volume. In these cells the regulation of the cell volume seems to be impaired, most likely as a consequence of the IClswell blockade. Similarly, 50 μM curcumin induced apoptosis, caused cell cycle arrest in G1-phase and increased the volume of human colorectal adenocarcinoma HT-29 cells. The cell cycle arrest in G1 phase may be the mechanism underlying the volume increase observed in this cell line after exposure to curcumin. PMID:22178266

The deubiquitinating enzyme DUBAI stabilizes DIAP1 to suppress Drosophila apoptosis

PubMed Central

Yang, C-S; Sinenko, S A; Thomenius, M J; Robeson, A C; Freel, C D; Horn, S R; Kornbluth, S

2014-01-01

Deubiquitinating enzymes (DUBs) counteract ubiquitin ligases to modulate the ubiquitination and stability of target signaling molecules. In Drosophila, the ubiquitin–proteasome system has a key role in the regulation of apoptosis, most notably, by controlling the abundance of the central apoptotic regulator DIAP1. Although the mechanism underlying DIAP1 ubiquitination has been extensively studied, the precise role of DUB(s) in controlling DIAP1 activity has not been fully investigated. Here we report the identification of a DIAP1-directed DUB using two complementary approaches. First, a panel of putative Drosophila DUBs was expressed in S2 cells to determine whether DIAP1 could be stabilized, despite treatment with death-inducing stimuli that would induce DIAP1 degradation. In addition, RNAi fly lines were used to detect modifiers of DIAP1 antagonist-induced cell death in the developing eye. Together, these approaches identified a previously uncharacterized protein encoded by CG8830, which we named DeUBiquitinating-Apoptotic-Inhibitor (DUBAI), as a novel DUB capable of preserving DIAP1 to dampen Drosophila apoptosis. DUBAI interacts with DIAP1 in S2 cells, and the putative active site of its DUB domain (C367) is required to rescue DIAP1 levels following apoptotic stimuli. DUBAI, therefore, represents a novel locus of apoptotic regulation in Drosophila, antagonizing cell death signals that would otherwise result in DIAP1 degradation. PMID:24362437

ERK2 phosphorylation of serine 77 regulates Bmf pro-apoptotic activity.

PubMed

Shao, Y; Aplin, A E

2012-01-19

B-cell lymphoma 2 (Bcl-2) homology 3 (BH3)-only proteins represent a class of pro-apoptotic factors that neutralize pro-survival Bcl-2 proteins, and, in some cases, directly activate Bax. The mechanisms of control and the role of BH3-only proteins, such as Bcl-2 like protein 11 extra large and Bad are well studied. By contrast, relatively little is known about the regulation and role of Bcl-2 modifying factor (Bmf). The B-RAF oncogene is mutated in ∼8% of human tumors. We have previously shown that Bmf is upregulated at the transcript level and is required for apoptosis induced by targeting B-RAF signaling in tumor cells harboring mutant B-RAF. In this study, we show that Bmf is regulated at the post-translational level by mutant B-RAF-MEK-ERK2 signaling. Extracellular signal-regulated kinase (ERK2) directly phosphorylates Bmf on serine 74 and serine 77 residues with serine 77 being the predominant site. In addition, serine 77 phosphorylation reduces Bmf pro-apoptotic activity likely through a mechanism independent of altering Bmf localization to the mitochondria and/or interactions with dynein light chain 2 and the pro-survival proteins, B-cell lymphoma extra large, Bcl-2 and Mcl-1. These data identify a novel mode of regulation in Bmf that modulates its pro-apoptotic activity in mutant B-RAF tumor cells.

Macrocycles that inhibit the binding between heat shock protein 90 and TPR-containing proteins

PubMed Central

Ardi, Veronica C.; Alexander, Leslie D.; Johnson, Victoria; McAlpine, Shelli R.

2011-01-01

Heat shock protein 90 (Hsp90) accounts for 1–2% of the total proteins in normal cells and functions as a molecular chaperone that folds, assembles, and stabilizes client proteins. Hsp90 is over-expressed (3–6-fold increase) in stressed cells, including cancer cells, and regulates over 200 client and co-chaperone proteins. Hsp90 client proteins are involved in a plethora of cellular signaling events including numerous growth and apoptotic pathways. Since pathway-specific inhibitors can be problematic in drug-resistant cancers, shutting down multiple pathways at once is a promising approach when developing new therapeutics. Hsp90’s ability to modulate many growth and signaling pathways simultaneously makes this protein an attractive target in the field of cancer therapeutics. Herein we present evidence that a small molecule modulates Hsp90 via binding between the N and middle domain and allosterically inhibiting the binding interaction between Hsp90 and four C-terminal binding client proteins: IP6K2, FKBP38, FKBP52, and HOP. These last three clients contain a tetratricopeptide-repeat (TPR) region, which is known to interact with the MEEVD sequence on the C-terminus of Hsp90. Thus, this small molecule modulates the activity between co-chaperones that contain TPR motifs and Hsp90’s MEEVD region. This mechanism of action is unique from that of all Hsp90 inhibitors currently in clinical trials where these molecules have no effect on proteins that bind to the C-terminus of Hsp90. Further, our small molecule induces a Caspase-3 dependent apoptotic event. Thus, we describe the mechanism of a novel scaffold that is a useful tool for studying cell-signaling events that result when blocking the MEEVD-TPR interaction between Hsp90 and co-chaperone proteins. PMID:21950602

Renoprotective effect of the isoflavonoid biochanin A against cisplatin induced acute kidney injury in mice: Effect on inflammatory burden and p53 apoptosis.

PubMed

Suliman, Faiha A; Khodeer, Dina M; Ibrahiem, Afaf; Mehanna, Eman T; El-Kherbetawy, Mohamed K; Mohammad, Hala M F; Zaitone, Sawsan A; Moustafa, Yasser M

2018-05-21

Cisplatin is a potent widely-used chemotherapeutics; however, its clinical use is associated with nephrotoxicity. Renoprotective approaches are being discovered to halt the tubular cell death due to inflammatory and apoptotic burdens. In the present study, the renoprotective effects of different doses of biochanin A (10, 20 or 40 mg/kg) in mice treated with a single injection of cisplatin (10 mg/kg) were reported. Cisplatin administration resulted in marked increases in serum creatinine and blood urea nitrogen. Further, renal homogenates showed increased level of inflammatory cytokines and upregulation of the expression of p53 up-regulated modulator of apoptosis (PUMA), p53 and caspase 3 but downregulation in Nrf2 expression. Furthermore, cisplatin group showed marked necrosis and degenerated tubular lining epithelial cells with frequently detected apoptotic bodies. Mice treated with biochanin A (10, 20 or 40 mg/kg) for 14 days prior to cisplatin abrogated cisplatin-mediated damage. Furthermore, the elevated serum creatinine and urea levels were lessened by some doses of biochanin A, indicating protection against renal injury. Similarly, the changes in apoptosis and inflammatory markers have ameliorated to significant levels (P < 0.05). The results suggest biochanin A as a nephroprotective agent against cisplatin toxicity. Overall, this nephroprotective effect of biochanin A involved anti-inflammatory and antiapoptotic activities. Copyright © 2018 Elsevier B.V. All rights reserved.

The roles of HOXB7 in promoting migration, invasion, and anti-apoptosis in gastric cancer.

PubMed

Joo, Moon Kyung; Park, Jong-Jae; Yoo, Hyo Soon; Lee, Beom Jae; Chun, Hoon Jai; Lee, Sang Woo; Bak, Young-Tae

2016-10-01

The aim of this study was to compare HOXB7 expression level between gastric cancer and non-cancerous gastric tissues. Additionally, the functional effects of HOXB7, including its pro-migration or invasion and anti-apoptosis roles, were evaluated in gastric cancer cells. Both gene and protein expression levels of HOXB7 were examined in gastric cancer cell lines, and HOXB7 expression was compared between primary or metastatic gastric cancer tissues and chronic gastritis or intestinal metaplasia tissues. Functional studies included a wound healing assay, a Matrigel invasion assay, and an Annexin-V assay were performed, and Akt/PTEN activity was measured by western blotting. Both gene and protein expression levels of HOXB7 could be clearly detected in various gastric cancer cell lines except MKN-28 cell. HOXB7 expression was significantly higher in primary or metastatic gastric cancer tissues than in chronic gastritis or intestinal metaplasia tissues. HOXB7 knockdown led to inhibition of cell invasion and migration, had an apoptotic effect, downregulated phosphor-Akt, and upregulated PTEN in AGS and SNU-638 cells. Reinforced expression of HOXB7 caused the opposite effects in MKN-28 and MKN-45 cells. Our study suggests that HOXB7 has an oncogenic role in gastric cancer, which might be related to the modulation of Akt/PTEN activity to induce cell migration/invasion and anti-apoptotic effects. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Allograft tolerance induced by donor apoptotic lymphocytes requires phagocytosis in the recipient

NASA Technical Reports Server (NTRS)

Sun, E.; Gao, Y.; Chen, J.; Roberts, A. I.; Wang, X.; Chen, Z.; Shi, Y.

2004-01-01

Cell death through apoptosis plays a critical role in regulating cellular homeostasis. Whether the disposal of apoptotic cells through phagocytosis can actively induce immune tolerance in vivo, however, remains controversial. Here, we report in a rat model that without using immunosuppressants, transfusion of apoptotic splenocytes from the donor strain prior to transplant dramatically prolonged survival of heart allografts. Histological analysis verified that rejection signs were significantly ameliorated. Splenocytes from rats transfused with donor apoptotic cells showed a dramatically decreased response to donor lymphocyte stimulation. Most importantly, blockade of phagocytosis in vivo, either with gadolinium chloride to disrupt phagocyte function or with annexin V to block binding of exposed phosphotidylserine to its receptor on phagocytes, abolished the beneficial effect of transfused apoptotic cells on heart allograft survival. Our results demonstrate that donor apoptotic cells promote specific allograft acceptance and that phagocytosis of apoptotic cells in vivo plays a crucial role in maintaining immune tolerance.

Curcumin inhibits cellular condensation and alters microfilament organization during chondrogenic differentiation of limb bud mesenchymal cells.

PubMed

Kim, Dong Kyun; Kim, Song Ja; Kang, Shin Sung; Jin, Eun Jung

2009-09-30

Curcumin is a well known natural polyphenol product isolated from the rhizome of the plant Curcuma longa, anti-inflammatory agent for arthritis by inhibiting synthesis of inflammatory prostaglandins. However, the mechanisms by which curcumin regulates the functions of chondroprogenitor, such as proliferation, precartilage condensation, cytoskeletal organization or overall chondrogenic behavior, are largely unknown. In the present report, we investigated the effects and signaling mechanism of curcumin on the regulation of chondrogenesis. Treating chick limb bud mesenchymal cells with curcumin suppressed chondrogenesis by stimulating apoptotic cell death. It also inhibited reorganization of the actin cytoskeleton into a cortical pattern concomitant with rounding of chondrogenic competent cells and down-regulation of integrin beta1 and focal adhesion kinase (FAK) phosphorylation. Curcumin suppressed the phosphorylation of Akt leading to Akt inactivation. Activation of Akt by introducing a myristoylated, constitutively active form of Akt reversed the inhibitory actions of curcumin during chondrogenesis. In summary, for the first time, we describe biological properties of curcumin during chondrogenic differentiation of chick limb bud mesenchymal cells. Curcumin suppressed chondrogenesis by stimulating apoptotic cell death and down-regulating integrin-mediated reorganization of actin cytoskeleton via modulation of Akt signaling.

Autophagy Has a Beneficial Role in Relieving Cigarette Smoke-Induced Apoptotic Death in Human Gingival Fibroblasts.

PubMed

Kim, Moon-Soo; Yun, Jeong-Won; Park, Jin-Ho; Park, Bong-Wook; Kang, Young-Hoon; Hah, Young-Sool; Hwang, Sun-Chul; Woo, Dong Kyun; Byun, June-Ho

2016-01-01

The deleterious role of cigarette smoke has long been documented in various human diseases including periodontal complications. In this report, we examined this adverse effect of cigarette smoke on human gingival fibroblasts (HGFs) which are critical not only in maintaining gingival tissue architecture but also in mediating immune responses. As well documented in other cell types, we also observed that cigarette smoke promoted cellular reactive oxygen species in HGFs. And we found that this cigarette smoke-induced oxidative stress reduced HGF viability through inducing apoptosis. Our results indicated that an increased Bax/Bcl-xL ratio and resulting caspase activation underlie the apoptotic death in HGFs exposed to cigarette smoke. Furthermore, we detected that cigarette smoke also triggered autophagy, an integrated cellular stress response. Interesting, a pharmacological suppression of the cigarette smoke-induced autophagy led to a further reduction in HGF viability while a pharmacological promotion of autophagy increased the viability of HGFs with cigarette smoke exposures. These findings suggest a protective role for autophagy in HGFs stressed with cigarette smoke, highlighting that modulation of autophagy can be a novel therapeutic target in periodontal complications with cigarette smoke.

Neutrophil Apoptosis: Relevance to the Innate Immune Response and Inflammatory Disease

PubMed Central

Fox, Sarah; Leitch, Andrew E.; Duffin, Rodger; Haslett, Christopher; Rossi, Adriano G.

2010-01-01

Neutrophils are the most abundant cell type involved in the innate immune response. They are rapidly recruited to sites of injury or infection where they engulf and kill invading microorganisms. Neutrophil apoptosis, the process of programmed cell death that prevents the release of neutrophil histotoxic contents, is tightly regulated and limits the destructive capacity of neutrophil products to surrounding tissue. The subsequent recognition and phagocytosis of apoptotic cells by phagocytic cells such as macrophages is central to the successful resolution of an inflammatory response and it is increasingly apparent that the dying neutrophil itself exerts an anti-inflammatory effect through modulation of surrounding cell responses, particularly macrophage inflammatory cytokine release. Apoptosis may be delayed, induced or enhanced by micro-organisms dependent on their immune evasion strategies and the health of the host they encounter. There is now an established field of research aimed at understanding the regulation of apoptosis and its potential as a target for therapeutic intervention in inflammatory and infective diseases. This review focuses on the physiological regulation of neutrophil apoptosis with respect to the innate immune system and highlights recent advances in mechanistic understanding of apoptotic pathways and their therapeutic manipulation in appropriate and excessive innate immune responses. PMID:20375550

Human hepatocytes apoptosis induced by replication of hepatitis B virus subgenotypes F1b and F4: Role of basal core promoter and preCore mutations.

PubMed

Elizalde, María Mercedes; Sevic, Ina; González López Ledesma, María Mora; Campos, Rodolfo Héctor; Barbini, Luciana; Flichman, Diego Martin

2018-01-01

In the context of pathogenesis of HBV infection, HBV genotypes and mutants have been shown to affect the natural course of chronic infection and treatment outcomes. In this work, we studied the induction of apoptosis by the replication of HBV subgenotypes F1b and F4, and the naturally occurring mutants BCP and preCore. Both subgenotypes F1b and F4 HBV genome transfections induced cell death by apoptosis in human hepatocytes. The BCPdm (A1762T/G1764A) and preCore (G1896A) mutants induced higher levels of apoptosis than the wt virus. This increase in apoptosis was not associated with the enhanced viral replication of the variants. HBV-mediated apoptosis was independent of viral subgenotypes, and associated with the modulation of members of the regulatory Bcl-2 family proteins expression in the mitochondrial apoptotic pathway. Finally, the apoptosis induction increase observed for the preCore mutants suggests that HBeAg might have an anti-apoptotic effect in human hepatocytes. Copyright © 2017 Elsevier Inc. All rights reserved.

Coriolus versicolor (Yunzhi) extract attenuates growth of human leukemia xenografts and induces apoptosis through the mitochondrial pathway.

PubMed

Ho, Cheong-Yip; Kim, Chi-Fai; Leung, Kwok-Nam; Fung, Kwok-Pui; Tse, Tak-Fu; Chan, Helen; Lau, Clara Bik-San

2006-09-01

Coriolus versicolor (CV), also called Yunzhi, has been demonstrated to exert anti-tumor effects on various types of cancer cells. Our previous studies have demonstrated that a standardized aqueous ethanol extract prepared from CV inhibited the proliferation of human leukemia cells via induction of apoptosis. The present study aimed to evaluate the underlying mechanisms of apoptosis through modulation of Bax, Bcl-2 and cytochrome c protein expressions in a human pro-myelocytic leukemia (HL-60) cell line, as well as the potential of the CV extract as anti-leukemia agent using the athymic mouse xenograft model. Our results demonstrated that the CV extract dose-dependently suppressed the proliferation of HL-60 cells (IC50 = 150.6 microg/ml), with increased nucleosome production from apoptotic cells. Expression of pro-apoptotic protein Bax was significantly up-regulated in HL-60 cells treated with the CV extract, especially after 16 and 24 h. Meanwhile, expression of anti-apoptotic protein Bcl-2 was concomitantly down-regulated, as reflected by the increased Bax/Bcl-2 ratio. The CV extract markedly, but transiently, promoted the release of cytochrome c from mitochondria to cytosol after 24-h incubation. In vivo studies in the athymic nude mouse xenograft model also confirmed the growth-inhibitory activity of the CV extract on human leukemia cells. In conclusion, the CV extract attenuated the human leukemia cell proliferation in vivo, and in vitro possibly by inducing apoptosis through the mitochondrial pathway. The CV extract is likely to be valuable for the treatment of some forms of human leukemia.

Calcium-permeable α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid Receptors Trigger Neuronal Nitric-oxide Synthase Activation to Promote Nerve Cell Death in an Src Kinase-dependent Fashion*

PubMed Central

Socodato, Renato; Santiago, Felipe N.; Portugal, Camila C.; Domingues, Ana F.; Santiago, Ana R.; Relvas, João B.; Ambrósio, António F.; Paes-de-Carvalho, Roberto

2012-01-01

In the retina information decoding is dependent on excitatory neurotransmission and is critically modulated by AMPA glutamate receptors. The Src-tyrosine kinase has been implicated in modulating neurotransmission in CNS. Thus, our main goal was to correlate AMPA-mediated excitatory neurotransmission with the modulation of Src activity in retinal neurons. Cultured retinal cells were used to access the effects of AMPA stimulation on nitric oxide (NO) production and Src phosphorylation. 4-Amino-5-methylamino-2′,7′-difluorofluorescein diacetate fluorescence mainly determined NO production, and immunocytochemistry and Western blotting evaluated Src activation. AMPA receptors activation rapidly up-regulated Src phosphorylation at tyrosine 416 (stimulatory site) and down-regulated phosphotyrosine 527 (inhibitory site) in retinal cells, an effect mainly mediated by calcium-permeable AMPA receptors. Interestingly, experiments confirmed that neuronal NOS was activated in response to calcium-permeable AMPA receptor stimulation. Moreover, data suggest NO pathway as a key regulatory signaling in AMPA-induced Src activation in neurons but not in glial cells. The NO donor SNAP (S-nitroso-N-acetyl-dl-penicillamine) and a soluble guanylyl cyclase agonist (YC-1) mimicked AMPA effect in Src Tyr-416 phosphorylation, reinforcing that Src activation is indeed modulated by the NO pathway. Gain and loss-of-function data demonstrated that ERK is a downstream target of AMPA-induced Src activation and NO signaling. Furthermore, AMPA stimulated NO production in organotypic retinal cultures and increased Src activity in the in vivo retina. Additionally, AMPA-induced apoptotic retinal cell death was regulated by both NOS and Src activity. Because Src activity is pivotal in several CNS regions, the data presented herein highlight that Src modulation is a critical step in excitatory retinal cell death. PMID:22992730

Calcium-permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors trigger neuronal nitric-oxide synthase activation to promote nerve cell death in an Src kinase-dependent fashion.

PubMed

Socodato, Renato; Santiago, Felipe N; Portugal, Camila C; Domingues, Ana F; Santiago, Ana R; Relvas, João B; Ambrósio, António F; Paes-de-Carvalho, Roberto

2012-11-09

In the retina information decoding is dependent on excitatory neurotransmission and is critically modulated by AMPA glutamate receptors. The Src-tyrosine kinase has been implicated in modulating neurotransmission in CNS. Thus, our main goal was to correlate AMPA-mediated excitatory neurotransmission with the modulation of Src activity in retinal neurons. Cultured retinal cells were used to access the effects of AMPA stimulation on nitric oxide (NO) production and Src phosphorylation. 4-Amino-5-methylamino-2',7'-difluorofluorescein diacetate fluorescence mainly determined NO production, and immunocytochemistry and Western blotting evaluated Src activation. AMPA receptors activation rapidly up-regulated Src phosphorylation at tyrosine 416 (stimulatory site) and down-regulated phosphotyrosine 527 (inhibitory site) in retinal cells, an effect mainly mediated by calcium-permeable AMPA receptors. Interestingly, experiments confirmed that neuronal NOS was activated in response to calcium-permeable AMPA receptor stimulation. Moreover, data suggest NO pathway as a key regulatory signaling in AMPA-induced Src activation in neurons but not in glial cells. The NO donor SNAP (S-nitroso-N-acetyl-DL-penicillamine) and a soluble guanylyl cyclase agonist (YC-1) mimicked AMPA effect in Src Tyr-416 phosphorylation, reinforcing that Src activation is indeed modulated by the NO pathway. Gain and loss-of-function data demonstrated that ERK is a downstream target of AMPA-induced Src activation and NO signaling. Furthermore, AMPA stimulated NO production in organotypic retinal cultures and increased Src activity in the in vivo retina. Additionally, AMPA-induced apoptotic retinal cell death was regulated by both NOS and Src activity. Because Src activity is pivotal in several CNS regions, the data presented herein highlight that Src modulation is a critical step in excitatory retinal cell death.

Dose-dependent responses of I3C and DIM on T-cell activation in the human T lymphocyte Jurkat cell line

USDA-ARS?s Scientific Manuscript database

Indole-3-carbinol (I3C) and its dimer diindolylmethane (DIM) are bioactive metabolites of a glucosinolate glucobrassicin found in cruciferous vegetables. Both I3C and DIM have been reported to possess anti-apoptotic, anti-proliferative and anti-carcinogenic properties via the modulation of immune p...

Cannabidiol as potential anticancer drug

PubMed Central

Massi, Paola; Solinas, Marta; Cinquina, Valentina; Parolaro, Daniela

2013-01-01

Over the past years, several lines of evidence support an antitumourigenic effect of cannabinoids including Δ9-tetrahydrocannabinol (Δ9-THC), synthetic agonists, endocannabinoids and endocannabinoid transport or degradation inhibitors. Indeed, cannabinoids possess anti-proliferative and pro-apoptotic effects and they are known to interfere with tumour neovascularization, cancer cell migration, adhesion, invasion and metastasization. However, the clinical use of Δ9-THC and additional cannabinoid agonists is often limited by their unwanted psychoactive side effects, and for this reason interest in non-psychoactive cannabinoid compounds with structural affinity for Δ9-THC, such as cannabidiol (CBD), has substantially increased in recent years. The present review will focus on the efficacy of CBD in the modulation of different steps of tumourigenesis in several types of cancer and highlights the importance of exploring CBD/CBD analogues as alternative therapeutic agents. PMID:22506672

BAD-Dependent Regulation of Fuel Metabolism and KATP Channel Activity Confers Resistance to Epileptic Seizures

PubMed Central

Giménez-Cassina, Alfredo; Martínez-François, Juan Ramón; Fisher, Jill K.; Szlyk, Benjamin; Polak, Klaudia; Wiwczar, Jessica; Tanner, Geoffrey R.; Lutas, Andrew; Yellen, Gary; Danial, Nika N.

2012-01-01

Summary Neuronal excitation can be substantially modulated by alterations in metabolism, as evident from the anticonvulsant effect of diets that reduce glucose utilization and promote ketone body metabolism. We provide genetic evidence that BAD, a protein with dual functions in apoptosis and glucose metabolism, imparts reciprocal effects on metabolism of glucose and ketone bodies in brain cells. These effects involve phospho-regulation of BAD and are independent of its apoptotic function. BAD modifications that reduce glucose metabolism produce a marked increase in the activity of metabolically sensitive KATP channels in neurons, as well as resistance to behavioral and electrographic seizures in vivo. Seizure resistance is reversed by genetic ablation of the KATP channel, implicating the BAD-KATP axis in metabolic control of neuronal excitation and seizure responses. PMID:22632729

Phenolic acid intake, delivered via moderate champagne wine consumption, improves spatial working memory via the modulation of hippocampal and cortical protein expression/activation.

PubMed

Corona, Giulia; Vauzour, David; Hercelin, Justine; Williams, Claire M; Spencer, Jeremy P E

2013-11-10

While much data exist for the effects of flavonoid-rich foods on spatial memory in rodents, there are no such data for foods/beverages predominantly containing hydroxycinnamates and phenolic acids. To address this, we investigated the effects of moderate Champagne wine intake, which is rich in these components, on spatial memory and related mechanisms relative to the alcohol- and energy-matched controls. In contrast to the isocaloric and alcohol-matched controls, supplementation with Champagne wine (1.78 ml/kg BW, alcohol 12.5% vol.) for 6 weeks led to an improvement in spatial working memory in aged rodents. Targeted protein arrays indicated that these behavioral effects were paralleled by the differential expression of a number of hippocampal and cortical proteins (relative to the isocaloric control group), including those involved in signal transduction, neuroplasticity, apoptosis, and cell cycle regulation. Western immunoblotting confirmed the differential modulation of brain-derived neurotrophic factor, cAMP response-element-binding protein (CREB), p38, dystrophin, 2',3'-cyclic-nucleotide 3'-phosphodiesterase, mammalian target of rapamycin (mTOR), and Bcl-xL in response to Champagne supplementation compared to the control drink, and the modulation of mTOR, Bcl-xL, and CREB in response to alcohol supplementation. Our data suggest that smaller phenolics such as gallic acid, protocatechuic acid, tyrosol, caftaric acid, and caffeic acid, in addition to flavonoids, are capable of exerting improvements in spatial memory via the modulation in hippocampal signaling and protein expression. Changes in spatial working memory induced by the Champagne supplementation are linked to the effects of absorbed phenolics on cytoskeletal proteins, neurotrophin expression, and the effects of alcohol on the regulation of apoptotic events in the hippocampus and cortex.

Apoptotic effect of a novel kefir product, PFT, on multidrug-resistant myeloid leukemia cells via a hole-piercing mechanism

PubMed Central

GHONEUM, MAMDOOH; GIMZEWSKI, JAMES

2014-01-01

We examined the apoptotic effect of a novel Probiotics Fermentation Technology (PFT) kefir grain product; PFT is a natural mixture composed primarily of Lactobacillus kefiri P-IF, a specific strain of L. kefiri with unique growth characteristics. The aim of this study was to examine the apoptotic effect of PFT on human multidrug-resistant (MDR) myeloid leukemia (HL60/AR) cells in vitro and explore the mechanistic approach underlying its effect. HL60/AR cells were cultured with PFT (0.6–5.0 mg/ml) for 3 days. The apoptotic effect of PFT was assessed through examination of percent apoptosis, caspase 3 activation, Bcl-2 expression levels and changes in mitochondrial membrane potential (MMP). PFT induced apoptosis in HL60/AR cells in a dose-dependent manner which was maximal at 67.5% for 5 mg/ml. Induction of apoptosis was associated with activation of caspase 3, decreased expression of Bcl-2 and decreased polarization of MMP. In addition, PFT showed a unique characteristic of piercing holes in HL60/AR cells, as indicated by AFM studies. This hole induction may be responsible for the apoptotic effect on cancer cells. These results suggest that PFT may act as a potential therapy for the treatment of MDR leukemia. PMID:24430613

The Effects of NAD+ on Apoptotic Neuronal Death and Mitochondrial Biogenesis and Function after Glutamate Excitotoxicity

PubMed Central

Wang, Xiaowan; Li, Hailong; Ding, Shinghua

2014-01-01

NAD+ is an essential co-enzyme for cellular energy metabolism and is also involved as a substrate for many cellular enzymatic reactions. It has been shown that NAD+ has a beneficial effect on neuronal survival and brain injury in in vitro and in vivo ischemic models. However, the effect of NAD+ on mitochondrial biogenesis and function in ischemia has not been well investigated. In the present study, we used an in vitro glutamate excitotoxicity model of primary cultured cortical neurons to study the effect of NAD+ on apoptotic neuronal death and mitochondrial biogenesis and function. Our results show that supplementation of NAD+ could effectively reduce apoptotic neuronal death, and apoptotic inducing factor translocation after neurons were challenged with excitotoxic glutamate stimulation. Using different approaches including confocal imaging, mitochondrial DNA measurement and Western blot analysis of PGC-1 and NRF-1, we also found that NAD+ could significantly attenuate glutamate-induced mitochondrial fragmentation and the impairment of mitochondrial biogenesis. Furthermore, NAD+ treatment effectively inhibited mitochondrial membrane potential depolarization and NADH redistribution after excitotoxic glutamate stimulation. Taken together, our results demonstrated that NAD+ is capable of inhibiting apoptotic neuronal death after glutamate excitotoxicity via preserving mitochondrial biogenesis and integrity. Our findings provide insights into potential neuroprotective strategies in ischemic stroke. PMID:25387075

Cobalt iron oxide nanoparticles induce cytotoxicity and regulate the apoptotic genes through ROS in human liver cells (HepG2).

PubMed

Ahamed, Maqusood; Akhtar, Mohd Javed; Khan, M A Majeed; Alhadlaq, Hisham A; Alshamsan, Aws

2016-12-01

Cobalt iron oxide (CoFe 2 O 4 ) nanoparticles (CIO NPs) have been one of the most widely explored magnetic NPs because of their excellent chemical stability, mechanical hardness and heat generating potential. However, there is limited information concerning the interaction of CIO NPs with biological systems. In this study, we investigated the reactive oxygen species (ROS) mediated cytotoxicity and apoptotic response of CIO NPs in human liver cells (HepG2). Diameter of crystalline CIO NPs was found to be 23nm with a band gap of 1.97eV. CIO NPs induced cell viability reduction and membrane damage, and degree of induction was dose- and time-dependent. CIO NPs were also found to induce oxidative stress revealed by induction of ROS, depletion of glutathione and lower activity of superoxide dismutase enzyme. Real-time PCR data has shown that mRNA level of tumor suppressor gene p53 and apoptotic genes (bax, CASP3 and CASP9) were higher, while the expression level of anti-apoptotic gene bcl-2 was lower in cells following exposure to CIO NPs. Activity of caspase-3 and caspase-9 enzymes was also higher in CIO NPs exposed cells. Furthermore, co-exposure of N-acetyl-cysteine (ROS scavenger) efficiently abrogated the modulation of apoptotic genes along with the prevention of cytotoxicity caused by CIO NPs. Overall, we observed that CIO NPs induced cytotoxicity and apoptosis in HepG2 cells through ROS via p53 pathway. This study suggests that toxicity mechanisms of CIO NPs should be further investigated in animal models. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of Malnutrition on Neutrophil/Mononuclear Cell Apoptotic Functions in Children with Acute Lymphoblastic Leukemia.

PubMed

Cakir, Fatma Betul; Berrak, Su Gülsün; Aydogan, Gonul; Tulunay, Aysin; Timur, Cetin; Canpolat, Cengiz; Eksioglu Demiralp, Emel

2017-04-01

Recent studies claim that apoptosis may explain immune dysfunction observed in malnutrition. The objective of this study was to determine the effect of malnutrition on apoptotic functions of phagocytic cells in acute lymphoblastic leukemia (ALL). Twenty-eight ALL patients (13 with malnutrition) and thirty controls were enrolled. Neutrophil and mononuclear cell apoptosis of ALL patients and the control group were studied on admission before chemotherapy and repeated at a minimum of three months after induction of chemotherapy or when the nutritional status of leukemic children improved. The apoptotic functions of both ALL groups on admission were significantly lower than those of the control group. The apoptotic functions were lower in ALL patients with malnutrition than those in ALL patients without malnutrition, but this was not statistically significant. The repeated apoptotic functions of both ALL groups were increased to similar values with the control group. This increase was found to be statistically significant. The apoptotic functions in ALL patients were not found to be affected by malnutrition. However, after dietary intervention, increased apoptotic functions in both ALL patient groups deserve mentioning. Dietary intervention should always be recommended as malnutrition or cachexia leads to multiple complications. Enhanced apoptosis might originate also from remission state of cancer.

Combinatorial usage of fungal polysaccharides from Cordyceps sinensis and Ganoderma atrum ameliorate drug-induced liver injury in mice.

PubMed

Fan, Songtao; Huang, Xiaojun; Wang, Sunan; Li, Chang; Zhang, Zhihong; Xie, Mingyong; Nie, Shaoping

2018-05-15

This study investigated the possible protective effect of combined fungal polysaccharides (CFP), consisting of Cordyceps sinensis polysaccharides (CSP) and Ganoderma atrum polysaccharides (PSG) with well-defined structural characteristics, against cyclophosphamide (CTX)-induced hepatotoxicity in mice. Our results indicated CFP effectively prevented the liver injury by decreasing toxicity markers (aspartate transaminase, alanine aminotransferase and alkaline phosphatase). Further biochemical and molecular analysis indicated CSP particularly inhibited the activation of Toll-like receptor 9 (TLR9) and its related inflammatory signals, including pro-inflammatory cytokines, inducible nitric oxide synthase, and cyclooxygenase-2 to modulate hepatic inflammation response. Relatively, through activation of peroxisome proliferator-activated receptor α (PPARα), PSG increased hepatic glutathione peroxidase and glutathione content depleted by CTX, as well as prevented mitochondria-dependent apoptosis with regulation on Bcl-2 family proteins (Bad, Bax and Bcl-2). In addition, protective effect of CFP was associated with enhanced modulations on cellular oxidant/antioxidant imbalance, mitochondrial apoptotic pathway and pro-inflammatory factors via PPARα upregulation and TLR9 downregulation. Taking together, the combinatorial approach based on CSP and PSG presented a practical option for the management of drug-induced liver injury. Copyright © 2018 Elsevier Ltd. All rights reserved.

Systems analysis of apoptotic priming in ovarian cancer identifies vulnerabilities and predictors of drug response.

PubMed

Zervantonakis, Ioannis K; Iavarone, Claudia; Chen, Hsing-Yu; Selfors, Laura M; Palakurthi, Sangeetha; Liu, Joyce F; Drapkin, Ronny; Matulonis, Ursula; Leverson, Joel D; Sampath, Deepak; Mills, Gordon B; Brugge, Joan S

2017-08-28

The lack of effective chemotherapies for high-grade serous ovarian cancers (HGS-OvCa) has motivated a search for alternative treatment strategies. Here, we present an unbiased systems-approach to interrogate a panel of 14 well-annotated HGS-OvCa patient-derived xenografts for sensitivity to PI3K and PI3K/mTOR inhibitors and uncover cell death vulnerabilities. Proteomic analysis reveals that PI3K/mTOR inhibition in HGS-OvCa patient-derived xenografts induces both pro-apoptotic and anti-apoptotic signaling responses that limit cell killing, but also primes cells for inhibitors of anti-apoptotic proteins. In-depth quantitative analysis of BCL-2 family proteins and other apoptotic regulators, together with computational modeling and selective anti-apoptotic protein inhibitors, uncovers new mechanistic details about apoptotic regulators that are predictive of drug sensitivity (BIM, caspase-3, BCL-X L ) and resistance (MCL-1, XIAP). Our systems-approach presents a strategy for systematic analysis of the mechanisms that limit effective tumor cell killing and the identification of apoptotic vulnerabilities to overcome drug resistance in ovarian and other cancers.High-grade serous ovarian cancers (HGS-OvCa) frequently develop chemotherapy resistance. Here, the authors through a systematic analysis of proteomic and drug response data of 14 HGS-OvCa PDXs demonstrate that targeting apoptosis regulators can improve response of these tumors to inhibitors of the PI3K/mTOR pathway.

NFκBP65 transcription factor modulates resistance to doxorubicin through ABC transporters in breast cancer.

PubMed

Velaei, Kobra; Samadi, Nasser; Soltani, Sina; Barazvan, Balal; Soleimani Rad, Jafar

2017-07-01

Shedding light on chemoresistance biology of breast cancer could contribute to enhance the clinical outcome. Intrinsic or acquired resistance to chemotherapy is a major problem in breast cancer treatment. The NFκB pathway by siRNAP65 and JSH-23 as a translocational inhibitor of NFκBP65 in the doxorubicin-resistant MCF-7 (MCF-7/Dox) and MCF-7 cells was blocked. Then, the ABC transporter expression and function were assessed by real-time qRT-PCR and flow cytometry, respectively. Induction of apoptosis was evaluated after inhibition of the NFΚB pathway as well. Our study underlined the upregulation of NFκBP65 and anti-apoptotic Bcl-2 and downregulation of pro-apoptotic Bax in the MCF-7/Dox cells compared with control MCF-7 cells. Here, we showed that interplay between nuclear factor kappa B P65 (NFkBP65) as a transcriptional regulator and ABC transporters in the MCF-7/Dox cancer cells. We found that inhibition of the elevated expression of NFκBP65 in the resistant breast cancer, whether translocational inhibition or silencing by siRNA, decreased the expression and function of MDR1 and MRP1 efflux pumps. Furthermore, the blockade of NFκBP65 promoted apoptosis via modulating Bcl-2 and BAX expression. After inhibition of the NFκBP65 signaling pathway, elevated baseline expression of survival Bcl-2 gene in the resistant breast cells significantly decreased. Suppression of the NFκB pathway has a profound dual impact on promoting the intrinsic apoptotic pathway and reducing ABC transporter function and expression, which are some of the chemoresistance features. It was speculated that the NFκB pathway directly acts on doxorubicin-induced MDR1 and MRP1 expression in MCF-7/Dox cells.

Receptor-interacting protein kinases modulate noise-induced sensory hair cell death

PubMed Central

Zheng, H-W; Chen, J; Sha, S-H

2014-01-01

Receptor-interacting protein (RIP) kinases promote the induction of necrotic cell death pathways. Here we investigated signaling pathways in outer hair cells (OHCs) of adult male CBA/J mice exposed to noise that causes permanent threshold shifts, with a particular focus on RIP kinase-regulated necroptosis. One hour after noise exposure, nuclei of OHCs in the basal region of the cochlea displayed both apoptotic and necrotic features. RIP1 and RIP3 protein levels increased and caspase-8 was activated. Treatment with pan-caspase inhibitor ZVAD blocked the activation of caspase-8 and reduced the number of apoptotic nuclei, while increasing levels of RIP1, RIP3, and necrotic OHCs. Conversely, treatment with necrosis inhibitor necrostatin-1 (Nec-1) or RIP3 siRNA (siRIP3) diminished noise-induced increases in RIP1 and RIP3, and decreased necrotic OHC nuclei. This treatment also increased the number of apoptotic nuclei without increasing activation of caspase-8. Consistent with the elevation of levels of RIP1 and RIP3, noise-induced active AMPKα levels increased with ZVAD treatment, but decreased with Nec-1 and siRIP3 treatment. Furthermore, treatment with siRIP3 did not alter the activation of caspase-8, but instead increased activation of caspase-9 and promoted endonuclease G translocation into OHC nuclei. Finally, auditory brainstem response functional measurements and morphological assessment of OHCs showed that ZVAD treatment reduces noise-induced deficits. This protective function is potentiated when combined with siRIP3 treatment. In conclusion, noise-induced OHC apoptosis and necrosis are modulated by caspases and RIP kinases, respectively. Inhibition of either pathway shifts the prevalence of OHC death to the alternative pathway. PMID:24874734

Quantitative biochemical characterization and biotechnological production of caspase modulator, XIAP: Therapeutic implications for apoptosis-associated diseases.

PubMed

Yun, Si-Eun; Nam, Min-Kyung; Rhim, Hyangshuk

2018-07-01

Regulating apoptosis is a common and essential therapeutic strategy for cancer and neurodegenerative disorders. Based on basic studies of apoptotic mechanisms, various researches have attempted to overcome the pathogenesis of such diseases by activating or inhibiting apoptosis. Generally, the biochemical characteristics of the target molecules should be evaluated along with understanding of their mechanisms of action during drug development. Among apoptotic regulators, XIAP serves as a potent negative regulator to block apoptosis through the inhibition of caspase (CASP)-9 and -3/7. Although XIAP is an attractive target with such apoptotic-modulating property, biochemical and biophysical studies of XIAP are still challenging. In this study, the CASP-9 and -3/7 inhibitors XIAP, 242Δ and Δ230 were prepared using the pGEX expression system and biochemically characterized. These inhibitors were expressed in Escherichia coli at a concentration of ≥20 mg/L culture under a native condition with 0.01 mM IPTG induction. Notably, using a simple and rapid affinity purification technique, these CASP-9 and -3/7 inhibitors have been purified, yielding ≥5 mg/L culture at approximately 90% purity. We have determined that HtrA2 specifically binds to the BIR2 and BIR3 of XIAP at a 1:1 molecular ratio. Moreover, in vitro cell-free CASP-9 and -3/7 activation-apoptosis assays have demonstrated that these purified XIAP proteins dramatically inhibit CASP-9 and -3/7 action. Our system is suitable for biochemical studies, such as quantitation of the number of molecules acting on the apoptosis regulation, and provides a basis and insights that can be applied to the development of therapeutic agents for neurodegenerative disorders and cancer. Copyright © 2018 Elsevier B.V. All rights reserved.

Combined effect of tumor necrosis factor (TNF)-alpha and heat shock protein (HSP)-70 in reducing apoptotic injury in hypoxia: a cell culture study.

PubMed

Goel, Gunjan; Guo, Miao; Ding, Jamie; Dornbos, David; Ali, Ahmer; Shenaq, Mohammed; Guthikonda, Murali; Ding, Yuchuan

2010-10-15

Studies have demonstrated neuroprotective effects of either TNF-alpha or HSP-70 in ischemia/reperfusion injury following exercise. However, the protective mechanisms involving combined effect of the two proteins, particularly in neuronal apoptosis, remain unclear. This study aims to elucidate the beneficial role of TNF-alpha and HSP-70 in the regulation of apoptotic proteins and ERK signaling in hypoxic injury. Cortical neurons from 20 Sprague-Dawley rat embryos were isolated and cultured in five groups with or without pretreatment with recombinant TNF-alpha, HSP-70 protein or both prior to hypoxic conditions: (1) control; (2) control/hypoxia; (3) TNF-alpha/hypoxia; (4) HSP-70/hypoxia and (5) TNF-alpha/HSP-70/hypoxia. Western blotting was used to detect pro- and anti-apoptotic proteins, including Bax, AIF, Bcl-xL, Bcl-2, and pERK1/2 protein. TNF-alpha and HSP-70 significantly (p<0.05) reduced the levels of pro-apoptotic proteins, Bax and AIF. Also, pretreatment of hypoxic brain tissue with TNF-alpha and HSP-70 significantly (p<0.05) enhanced the levels of anti-apoptotic protein, Bcl-xL. TNF-alpha and HSP-70 together increased Bcl-2 levels by 70%. Hypoxia caused a significant (p<0.05) increase in ERK1/2 phosphorylation levels by 224%. The most effective inhibition of ERK levels was obtained by the combined administration of TNF-alpha and HSP-70. This study suggested that TNF-alpha and HSP-70 together enhance the decrease in pro-apoptotic protein levels and the increase in anti-apoptotic protein levels in the event of neuronal hypoxia through ERK1/2 signal transduction. 2010. Published by Elsevier Ireland Ltd.

Effect of homeopathic treatment on gene expression in Copenhagen rat tumor tissues.

PubMed

Thangapazham, Rajesh L; Rajeshkumar, N V; Sharma, Anuj; Warren, Jim; Singh, Anoop K; Ives, John A; Gaddipati, Jaya P; Maheshwari, Radha K; Jonas, Wayne B

2006-12-01

Increasing evidence suggests that the inability to undergo apoptosis is an important factor in the development and progression of prostate cancer. Agents that induce apoptosis may inhibit tumor growth and provide therapeutic benefit. In a recent study, the authors found that certain homeopathic treatments produced anticancer effects in an animal model. In this study, the authors examined the immunomodulating and apoptotic effects of these remedies. The authors investigated the effect of a homeopathic treatment regimen containing Conium maculatum, Sabal serrulata, Thuja occidentalis, and a MAT-LyLu Carcinosin nosode on the expression of cytokines and genes that regulate apoptosis. This was assessed in prostate cancer tissues, extracted from animals responsive to these drugs, using ribonuclease protection assay or reverse transcription polymerase chain reaction. There were no significant changes in mRNA levels of the apoptotic genes bax, bcl-2, bcl-x, caspase-1, caspase-2, caspase-3, Fas, FasL, or the cytokines interleukin (IL)-1alpha, IL-1beta, tumor necrosis factor (TNF)-beta, IL-3, IL-4, IL-5, IL-6, IL-10, TNF-alpha, IL-2, and interferon-gamma in prostate tumor and lung metastasis after treatment with homeopathic medicines. This study indicates that treatment with the highly diluted homeopathic remedies does not alter the gene expression in primary prostate tumors or in lung metastasis. The therapeutic effect of homeopathic treatments observed in the in vivo experiments cannot be explained by mechanisms based on distinct alterations in gene expression related to apoptosis or cytokines. Future research should explore subtle modulations in the expression of multiple genes in different biological pathways.

Assessment of herb-drug synergy to combat doxorubicin induced cardiotoxicity.

PubMed

Jain, Aditi; Rani, Vibha

2018-07-15

Aim Doxorubicin (Dox) is one of the most cardiotoxic anti-cancerous drug that is widely used for broad-range of cancers. There is an urgent need for developing cardio-oncological therapeutic interventions. Natural products having both anti-cancerous potential as well as cardioprotective effects may hold a great potential in this regard. Curcuma longa (an Indian herb) polyphenols including curcumin, and well known for its anti-oxidative and anti-cancerous potential was used in the present study for its synergistic effect on cancer cells and cardiomyocytes. Preliminary dose dependent analysis for cell viability was conducted by MTT and trypan blue assays where the effects of curcumin and Dox on cancer cell progression and cardiotoxicity were studied. Microscopic studies were done to analyse the morphological alterations of cells followed by intracellular ROS production studies by NBT and DCFH-DA assays. Apoptotic cellular death was studied by caspase activity and Annexin/PI FACS analysis. TUNEL assay was done followed by expression analysis of different cellular death biomarkers by quantitative real-time PCR. We observed that dose dependent cardiotoxicity of Dox can be significantly minimized by supplementing it with curcumin. Curcumin supplementation exaggerates oxidative stress and apoptosis leading to cancer cell death by modulating pro- and anti-apoptotic biomarkers. The combination treatment with curcumin results in achieving the desired anti-cancerous effect of Dox without compromising its activity and hence, reduces the possibility of its dose mediated cardiotoxic effects. Hence, curcumin holds a great potential for cardio-oncological therapeutic interventions. Copyright © 2018 Elsevier Inc. All rights reserved.

Resveratrol ameliorates spatial learning memory impairment induced by Aβ1-42 in rats.

PubMed

Wang, Rui; Zhang, Yu; Li, Jianguo; Zhang, Ce

2017-03-06

β-amyloid (Aβ) deposition is considered partially responsible for cognitive dysfunction in Alzheimer's disease (AD). Recently, resveratrol has been reported to play a potential role as a neuroprotective biofactor by modulating Aβ pathomechanisms, including through anti-neuronal apoptotic, anti-oxidative stress, and anti-neuroinflammatory effects. In addition, SIRT1 has been demonstrated to modulate learning and memory function by regulating the expression of cAMP response binding protein (CREB), which involves in modulating the expression of SIRT1. However, whether resveratrol can alleviate Aβ-induced cognitive dysfunction, whether SIRT1 expression and CREB phosphorylation in the hippocampus are affected by Aβ, and whether resveratrol influences these effects remain unknown. In the present study, we used a hippocampal injection model in rats to investigate the effects of resveratrol on Aβ 1-42 -induced impairment of spatial learning, memory and synaptic plasticity as well as on alterations of SIRT1 expression and CREB phosphorylation. We found that resveratrol significantly reversed the water maze behavioral impairment and the attenuation of long-term potentiation (LTP) in area CA1 that were induced by hippocampal injection of Aβ 1-42 . Interestingly, resveratrol also prevented the Aβ 1-42 -induced reductions in SIRT1 expression and CREB phosphorylation in rat hippocampus. In conclusion, in rats, resveratrol protects neurons against Aβ 1-42 -induced disruption of spatial learning, memory and hippocampal LTP. The mechanisms underlying the neuroprotective effects may involve rescue of SIRT1 expression and CREB phosphorylation. Copyright © 2016. Published by Elsevier Ltd.

Apigenin potentiates TRAIL therapy of non-small cell lung cancer via upregulating DR4/DR5 expression in a p53-dependent manner

PubMed Central

Chen, Minghui; Wang, Xueshi; Zha, Daolong; Cai, Fangfang; Zhang, Wenjing; He, Yan; Huang, Qilai; Zhuang, Hongqin; Hua, Zi-Chun

2016-01-01

Apigenin (APG) is an edible plant-derived flavonoid that shows modest antitumor activities in vitro and in vivo. APG treatment results in cell growth arrest and apoptosis in various types of tumors by modulating several signaling pathways. In the present study, we evaluated interactions between APG and TRAIL in non-small cell lung cancer (NSCLC) cells. We observed a synergistic effect between APG and TRAIL on apoptosis of NSCLC cells. A549 cells and H1299 cells were resistant to TRAIL treatment alone. The presence of APG sensitized NSCLC cells to TRAIL-induced apoptosis by upregulating the levels of death receptor 4 (DR4) and death receptor 5 (DR5) in a p53-dependent manner. Consistently, the pro-apoptotic proteins Bad and Bax were upregulated, while the anti-apoptotic proteins Bcl-xl and Bcl-2 were downregulated. Meanwhile, APG suppressed NF-κB, AKT and ERK activation. Treatment with specific small-molecule inhibitors of these pathways enhanced TRAIL-induced cell death, mirroring the effect of APG. Furthermore, using a mouse xenograft model, we demonstrated that the combined treatment completely suppressed tumor growth as compared with APG or TRAIL treatment alone. Our results demonstrate a novel strategy to enhance TRAIL-induced antitumor activity in NSCLC cells by APG via inhibition of the NF-κB, AKT and ERK prosurvival regulators. PMID:27752089

Apigenin potentiates TRAIL therapy of non-small cell lung cancer via upregulating DR4/DR5 expression in a p53-dependent manner.

PubMed

Chen, Minghui; Wang, Xueshi; Zha, Daolong; Cai, Fangfang; Zhang, Wenjing; He, Yan; Huang, Qilai; Zhuang, Hongqin; Hua, Zi-Chun

2016-10-18

Apigenin (APG) is an edible plant-derived flavonoid that shows modest antitumor activities in vitro and in vivo. APG treatment results in cell growth arrest and apoptosis in various types of tumors by modulating several signaling pathways. In the present study, we evaluated interactions between APG and TRAIL in non-small cell lung cancer (NSCLC) cells. We observed a synergistic effect between APG and TRAIL on apoptosis of NSCLC cells. A549 cells and H1299 cells were resistant to TRAIL treatment alone. The presence of APG sensitized NSCLC cells to TRAIL-induced apoptosis by upregulating the levels of death receptor 4 (DR4) and death receptor 5 (DR5) in a p53-dependent manner. Consistently, the pro-apoptotic proteins Bad and Bax were upregulated, while the anti-apoptotic proteins Bcl-xl and Bcl-2 were downregulated. Meanwhile, APG suppressed NF-κB, AKT and ERK activation. Treatment with specific small-molecule inhibitors of these pathways enhanced TRAIL-induced cell death, mirroring the effect of APG. Furthermore, using a mouse xenograft model, we demonstrated that the combined treatment completely suppressed tumor growth as compared with APG or TRAIL treatment alone. Our results demonstrate a novel strategy to enhance TRAIL-induced antitumor activity in NSCLC cells by APG via inhibition of the NF-κB, AKT and ERK prosurvival regulators.

Camel milk triggers apoptotic signaling pathways in human hepatoma HepG2 and breast cancer MCF7 cell lines through transcriptional mechanism.

PubMed

Korashy, Hesham M; Maayah, Zaid H; Abd-Allah, Adel R; El-Kadi, Ayman O S; Alhaider, Abdulqader A

2012-01-01

Few published studies have reported the use of crude camel milk in the treatment of stomach infections, tuberculosis and cancer. Yet, little research was conducted on the effect of camel milk on the apoptosis and oxidative stress associated with human cancer. The present study investigated the effect and the underlying mechanisms of camel milk on the proliferation of human cancer cells using an in vitro model of human hepatoma (HepG2) and human breast (MCF7) cancer cells. Our results showed that camel milk, but not bovine milk, significantly inhibited HepG2 and MCF7 cells proliferation through the activation of caspase-3 mRNA and activity levels, and the induction of death receptors in both cell lines. In addition, Camel milk enhanced the expression of oxidative stress markers, heme oxygenase-1 and reactive oxygen species production in both cells. Mechanistically, the increase in caspase-3 mRNA levels by camel milk was completely blocked by the transcriptional inhibitor, actinomycin D; implying that camel milk increased de novo RNA synthesis. Furthermore, Inhibition of the mitogen activated protein kinases differentially modulated the camel milk-induced caspase-3 mRNA levels. Taken together, camel milk inhibited HepG2 and MCF7 cells survival and proliferation through the activation of both the extrinsic and intrinsic apoptotic pathways.

Tangeretin Alleviates Cisplatin-Induced Acute Hepatic Injury in Rats: Targeting MAPKs and Apoptosis.

PubMed

Omar, Hany A; Mohamed, Wafaa R; Arab, Hany H; Arafa, El-Shaimaa A

2016-01-01

Despite its broad applications, cisplatin affords considerable nephro- and hepatotoxicity through triggering inflammatory and oxidative stress cascades. The aim of the current investigation was to study the possible protective effects of tangeretin on cisplatin-induced hepatotoxicity. The impact of tangeretin on cisplatin-evoked hepatic dysfunction and histopathologic changes along with oxidative stress, inflammatory and apoptotic biomarkers were investigated compared to silymarin. Tangeretin pre-treatment significantly improved liver function tests (ALT and AST), inhibited cisplatin-induced lipid profile aberrations (total cholesterol and triglycerides) and diminished histopathologic structural damage in liver tissues. Tangeretin also attenuated cisplatin-induced hepatic inflammatory events as indicated by suppression of tumor necrosis factor-α (TNF-α) and enhancement of interleukin-10 (IL-10). Meanwhile, it lowered malondialdehyde (MDA), nitric oxide (NO) and nuclear factor erythroid 2-related factor 2 (NRF-2) levels with restoration of glutathione (GSH), and glutathione peroxidase (GPx). Regarding mitogen-activated protein kinase (MAPK) pathway, tangeretin attenuated cisplatin-induced increase in phospho-p38, phospho-c-Jun N-terminal kinase (p-JNK) and phospho-extracellular signal-regulated kinase (p-ERK1/2) in liver tissues. In addition, tangeretin downregulated Bax expression with augmentation of Bcl-2 promoting liver cell survival. Our results highlight the protective effects of tangeretin against cisplatin-induced acute hepatic injury via the concerted modulation of inflammation, oxidative stress, MAPKs and apoptotic pathways.

Tamoxifen induces apoptotic neutrophil efferocytosis in horses.

PubMed

Olave, C; Morales, N; Uberti, B; Henriquez, C; Sarmiento, J; Ortloff, A; Folch, H; Moran, G

2018-03-01

Macrophages and neutrophils are important cellular components in the process of acute inflammation and its subsequent resolution, and evidence increasingly suggests that they play important functions during the resolution of chronic, adaptive inflammatory processes. Exacerbated neutrophil activity can be harmful to surrounding tissues; this is important in a range of diseases, including allergic asthma and chronic obstructive pulmonary disease in humans, and equine asthma (also known as recurrent airway obstruction (RAO). Tamoxifen (TX) is a non-steroidal estrogen receptor modulator with effects on cell growth and survival. Previous studies showed that TX treatment in horses with induced acute pulmonary inflammation promoted early apoptosis of blood and BALF neutrophils, reduction of BALF neutrophils, and improvement in animals' clinical status. The aim of this study was to describe if TX induces in vitro efferocytosis of neutrophils by alveolar macrophages. Efferocytosis assay, myeloperoxidase (MPO) detection and translocation phosphatidylserine (PS) were performed on neutrophils isolated from peripheral blood samples from five healthy horses. In in vitro samples from heathy horses, TX treatment increases the phenomenon of efferocytosis of peripheral neutrophils by alveolar macrophages. Similar increases in supernatant MPO concentration and PS translocation were observed in TX-treated neutrophils, compared to control cells. In conclusion, these results confirm that tamoxifen has a direct effect on equine peripheral blood neutrophils, through stimulation of the engulfment of apoptotic neutrophils by alveolar macrophages.

Nerve growth factor reduces apoptotic cell death in rat facial motor neurons after facial nerve injury.

PubMed

Hui, Lian; Yuan, Jing; Ren, Zhong; Jiang, Xuejun

2015-01-01

To assess the effects of nerve growth factor (NGF) on motor neurons after induction of a facial nerve lesion, and to compare the effects of different routes of NGF injection on motor neuron survival. This study was carried out in the Department of Otolaryngology Head & Neck Surgery, China Medical University, Liaoning, China from October 2012 to March 2013. Male Wistar rats (n = 65) were randomly assigned into 4 groups: A) healthy controls; B) facial nerve lesion model + normal saline injection; C) facial nerve lesion model + NGF injection through the stylomastoid foramen; D) facial nerve lesion model + intraperitoneal injection of NGF. Apoptotic cell death was detected using the terminal deoxynucleotidyl transferase dUTP nick end-labeling assay. Expression of caspase-3 and p53 up-regulated modulator of apoptosis (PUMA) was determined by immunohistochemistry. Injection of NGF significantly reduced cell apoptosis, and also greatly decreased caspase-3 and PUMA expression in injured motor neurons. Group C exhibited better efficacy for preventing cellular apoptosis and decreasing caspase-3 and PUMA expression compared with group D (p<0.05). Our findings suggest that injections of NGF may prevent apoptosis of motor neurons by decreasing caspase-3 and PUMA expression after facial nerve injury in rats. The NGF injected through the stylomastoid foramen demonstrated better protective efficacy than when injected intraperitoneally.

Natural Compounds As Modulators of Non-apoptotic Cell Death in Cancer Cells

PubMed Central

Guamán-Ortiz, Luis Miguel; Orellana, Maria Isabel Ramirez; Ratovitski, Edward A.

2017-01-01

Cell death is an innate capability of cells to be removed from microenvironment, if and when they are damaged by multiple stresses. Cell death is often regulated by multiple molecular pathways and mechanism, including apoptosis, autophagy, and necroptosis. The molecular network underlying these processes is often intertwined and one pathway can dynamically shift to another one acquiring certain protein components, in particular upon treatment with various drugs. The strategy to treat human cancer ultimately relies on the ability of anticancer therapeutics to induce tumor-specific cell death, while leaving normal adjacent cells undamaged. However, tumor cells often develop the resistance to the drug-induced cell death, thus representing a great challenge for the anticancer approaches. Numerous compounds originated from the natural sources and biopharmaceutical industries are applied today in clinics showing advantageous results. However, some exhibit serious toxic side effects. Thus, novel effective therapeutic approaches in treating cancers are continued to be developed. Natural compounds with anticancer activity have gained a great interest among researchers and clinicians alike since they have shown more favorable safety and efficacy then the synthetic marketed drugs. Numerous studies in vitro and in vivo have found that several natural compounds display promising anticancer potentials. This review underlines certain information regarding the role of natural compounds from plants, microorganisms and sea life forms, which are able to induce non-apoptotic cell death in tumor cells, namely autophagy and necroptosis. PMID:28367073

Modeling gene-environment interactions in oral cavity and esophageal cancers demonstrates a role for the p53 R72P polymorphism in modulating susceptibility.

PubMed

Sarkar, Jayanta; Dominguez, Emily; Li, Guojun; Kusewitt, Donna F; Johnson, David G

2014-08-01

A large number of epidemiological studies have linked a common single-nucleotide polymorphism (SNP) in the human p53 gene to risk for developing a variety of cancers. This SNP encodes either an arginine or proline at position 72 (R72P) of the p53 protein, which can alter the apoptotic activity of p53 via transcriptional and non-transcriptional mechanisms. This SNP has also been reported to modulate the development of human papilloma virus (HPV)-driven cancers through differential targeting of the p53 variant proteins by the E6 viral oncoprotein. Mouse models for the p53 R72P polymorphism have recently been developed but a role for this SNP in modifying cancer risk in response to viral and chemical carcinogens has yet to be established experimentally. Here, we demonstrate that the p53 R72P polymorphism modulates the hyperprolferative, apoptotic and inflammatory phenotypes caused by expression of the HPV16 E6 and E7 oncoproteins. Moreover, the R72P SNP also modifies the carcinogenic response to the chemical carcinogen 4NQO, in the presence and absence of the HPV16 transgene. Our findings confirm several human epidemiological studies associating the codon 72 proline variant with increased risk for certain cancers but also suggest that there are tissue-specific differences in how the R72P polymorphism influences the response to environmental carcinogens. © 2013 Wiley Periodicals, Inc.

Astaxanthin attenuates early acute kidney injury following severe burns in rats by ameliorating oxidative stress and mitochondrial-related apoptosis.

PubMed

Guo, Song-Xue; Zhou, Han-Lei; Huang, Chun-Lan; You, Chuan-Gang; Fang, Quan; Wu, Pan; Wang, Xin-Gang; Han, Chun-Mao

2015-04-13

Early acute kidney injury (AKI) is a devastating complication in critical burn patients, and it is associated with severe morbidity and mortality. The mechanism of AKI is multifactorial. Astaxanthin (ATX) is a natural compound that is widely distributed in marine organisms; it is a strong antioxidant and exhibits other biological effects that have been well studied in various traumatic injuries and diseases. Hence, we attempted to explore the potential protection of ATX against early post burn AKI and its possible mechanisms of action. The classic severe burn rat model was utilized for the histological and biochemical assessments of the therapeutic value and mechanisms of action of ATX. Upon ATX treatment, renal tubular injury and the levels of serum creatinine and neutrophil gelatinase-associated lipocalin were improved. Furthermore, relief of oxidative stress and tubular apoptosis in rat kidneys post burn was also observed. Additionally, ATX administration increased Akt and Bad phosphorylation and further down-regulated the expression of other downstream pro-apoptotic proteins (cytochrome c and caspase-3/9); these effects were reversed by the PI3K inhibitor LY294002. Moreover, the protective effect of ATX presents a dose-dependent enhancement. The data above suggested that ATX protects against early AKI following severe burns in rats, which was attributed to its ability to ameliorate oxidative stress and inhibit apoptosis by modulating the mitochondrial-apoptotic pathway, regarded as the Akt/Bad/Caspases signalling cascade.

Astaxanthin Attenuates Early Acute Kidney Injury Following Severe Burns in Rats by Ameliorating Oxidative Stress and Mitochondrial-Related Apoptosis

PubMed Central

Guo, Song-Xue; Zhou, Han-Lei; Huang, Chun-Lan; You, Chuan-Gang; Fang, Quan; Wu, Pan; Wang, Xin-Gang; Han, Chun-Mao

2015-01-01

Early acute kidney injury (AKI) is a devastating complication in critical burn patients, and it is associated with severe morbidity and mortality. The mechanism of AKI is multifactorial. Astaxanthin (ATX) is a natural compound that is widely distributed in marine organisms; it is a strong antioxidant and exhibits other biological effects that have been well studied in various traumatic injuries and diseases. Hence, we attempted to explore the potential protection of ATX against early post burn AKI and its possible mechanisms of action. The classic severe burn rat model was utilized for the histological and biochemical assessments of the therapeutic value and mechanisms of action of ATX. Upon ATX treatment, renal tubular injury and the levels of serum creatinine and neutrophil gelatinase-associated lipocalin were improved. Furthermore, relief of oxidative stress and tubular apoptosis in rat kidneys post burn was also observed. Additionally, ATX administration increased Akt and Bad phosphorylation and further down-regulated the expression of other downstream pro-apoptotic proteins (cytochrome c and caspase-3/9); these effects were reversed by the PI3K inhibitor LY294002. Moreover, the protective effect of ATX presents a dose-dependent enhancement. The data above suggested that ATX protects against early AKI following severe burns in rats, which was attributed to its ability to ameliorate oxidative stress and inhibit apoptosis by modulating the mitochondrial-apoptotic pathway, regarded as the Akt/Bad/Caspases signalling cascade. PMID:25871290

Baicalein antagonizes rotenone-induced apoptosis in dopaminergic SH-SY5Y cells related to Parkinsonism

PubMed Central

2012-01-01

Background Two active compounds, baicalein and its glycoside baicalin were found in the dried root of Scutellaria baicalensis Georgi, and reported to be neuroprotective in vitro and in vivo. This study aims to evaluate the protective effects of baicalein on the rotenone-induced apoptosis in dopaminergic SH-SY5Y cells related to parkinsonism. Methods Cell viability and cytotoxicity were determined by MTT assay. The degree of nuclear apoptosis was evaluated with a fluorescent DNA-binding probe Hoechst 33258. The production of reactive oxidative species (ROS) and loss of mitochondrial membrane potential (ΔΨm) were determined by fluorescent staining with DCFH-DA and Rhodanmine 123, respectively. The expression of Bax, Bcl-2, cleaved caspase-3 and phosphorylated ERK1/2 was determined by the Western blots. Results Baicalein significantly increased viability and decreased rotenone-induced death of SH-SY5Y cells in a dose-dependent manner. Pre- and subsequent co-treatment with baicalein preserved the cell morphology and attenuated the nuclear apoptotic characteristics triggered by rotenone. Baicalein antagonized rotenone-induced overproduction of ROS, loss of ΔΨm, the increased expression of Bax, cleaved caspase-3 and phosphorylated ERK1/2 and the decreased expression of Bcl-2. Conclusion The antioxidative effect, mitochondrial protection and modulation of anti-and pro-apoptotic proteins are related to the neuroprotective effects of baicalein against rotenone induced cell death in SH-SY5Y cells. PMID:22264378

The antihypertension drug doxazosin suppresses JAK/STATs phosphorylation and enhances the effects of IFN-α/γ-induced apoptosis.

PubMed

Park, Mi Sun; Kim, Boh-Ram; Kang, Sokbom; Kim, Dae-Yong; Rho, Seung Bae

2014-11-01

Doxazosin, a commonly prescribed treatment for patients with benign prostatic hyperplasia, serves as an α1-blocker of the adrenergic receptors. In this study, we calculated its effect on the ovarian carcinoma cells. Doxazosin induces dose-dependent growth suppression and is additively activated through IFN-α or IFN-γ stimulation. They both enhanced G1 phase arrest, as well as the activity of caspase-3, and the reduction of cyclin D1 and CDK4 protein levels. Doxazosin growth suppression was abolished either by the Janus family of tyrosine kinase (JAK) or the signal transducer and activator of transcription (STAT) inhibitor treatment. The activity of JAK/STAT was dependent on the level of doxazosin, suggesting a requirement of doxazosin for the activation of JAK/STAT. Furthermore, doxazosin plus IFN-α or doxazosin plus IFN-γ additively suppressed the activation of the JAK/STAT signals through phosphorylation of JAK and STAT, thus affecting the activation of subsequent downstream signaling components PI3K, mTOR, 70S6K, and PKCδ. In vivo study demonstrated that doxazosin significantly suppressed tumor growth in an ovarian cancer cell xenograft mouse model, inducing apoptotic cell death by up-regulating the expression of p53, whereas c-Myc expression was markedly reduced. Our data indicate that doxazosin can modulate the apoptotic effects of IFN-α- and IFN-γ through the JAK/STAT signaling pathways. Collectively, we indicate that this action may be a potent chemotherapeutic property against ovarian carcinoma.

Decursin and decursinol angelate: molecular mechanism and therapeutic potential in inflammatory diseases.

PubMed

Shehzad, Adeeb; Parveen, Sajida; Qureshi, Munibah; Subhan, Fazli; Lee, Young Sup

2018-03-01

Epidemiological studies have shown that inflammation plays a critical role in the development and progression of various chronic diseases, including cancers, neurological diseases, hepatic fibrosis, diabetic retinopathy, and vascular diseases. Decursin and decursinol angelate (DA) are pyranocoumarin compounds obtained from the roots of Angelica gigas. Several studies have described the anti-inflammatory effects of decursin and DA. Decursin and DA have shown potential anti-inflammatory activity by modulating growth factors such as vascular endothelial growth factor, transcription factors such as signal transducer and activator of transcription 3 and nuclear factor kappa-light-chain-enhancer of activated B cells, cellular enzymes including matrix metalloproteinases cyclooxygenase, and protein kinases such as extracellular receptor kinase, phosphatidylinositol-3-kinase, and protein kinase C. These compounds have the ability to induce apoptosis by activating pro-apoptotic proteins and the caspase cascade, and reduced the expression of anti-apoptotic proteins such as B-cell lymphoma 2 and B-cell lymphoma-extra-large. Interaction with multiple molecular targets and cytotoxic effects, these two compounds are favorable candidates for treating various chronic inflammatory diseases such as cancers (prostate, breast, leukemia, cervical, and myeloma), rheumatoid arthritis, diabetic retinopathy, hepatic fibrosis, osteoclastogenesis, allergy, and Alzheimer's disease. We have summarized the preliminary studies regarding the biological effects of decursin and DA. In this review, we will also highlight the functions of coumarin compounds that can be translated to a clinical practice for the treatment and prevention of various inflammatory ailments.

Expression and function of methylthioadenosine phosphorylase in chronic liver disease.

PubMed

Czech, Barbara; Dettmer, Katja; Valletta, Daniela; Saugspier, Michael; Koch, Andreas; Stevens, Axel P; Thasler, Wolfgang E; Müller, Martina; Oefner, Peter J; Bosserhoff, Anja-Katrin; Hellerbrand, Claus

2013-01-01

To study expression and function of methylthioadenosine phosphorylase (MTAP), the rate-limiting enzyme in the methionine and adenine salvage pathway, in chronic liver disease. MTAP expression was analyzed by qRT-PCR, Western blot and immunohistochemical analysis. Levels of MTA were determined by liquid chromatography-tandem mass spectrometry. MTAP was downregulated in hepatocytes in murine fibrosis models and in patients with chronic liver disease, leading to a concomitant increase in MTA levels. In contrast, activated hepatic stellate cells (HSCs) showed strong MTAP expression in cirrhotic livers. However, also MTA levels in activated HSCs were significantly higher than in hepatocytes, and there was a significant correlation between MTA levels and collagen expression in diseased human liver tissue indicating that activated HSCs significantly contribute to elevated MTA in diseased livers. MTAP suppression by siRNA resulted in increased MTA levels, NFκB activation and apoptosis resistance, while overexpression of MTAP caused the opposite effects in HSCs. The anti-apoptotic effect of low MTAP expression and high MTA levels, respectively, was mediated by induced expression of survivin, while inhibition of survivin abolished the anti-apoptotic effect of MTA on HSCs. Treatment with a DNA demethylating agent induced MTAP and reduced survivin expression, while oxidative stress reduced MTAP levels but enhanced survivin expression in HSCs. MTAP mediated regulation of MTA links polyamine metabolism with NFκB activation and apoptosis in HSCs. MTAP and MTAP modulating mechanisms appear as promising prognostic markers and therapeutic targets for hepatic fibrosis.

Expression and Function of Methylthioadenosine Phosphorylase in Chronic Liver Disease

PubMed Central

Czech, Barbara; Dettmer, Katja; Valletta, Daniela; Saugspier, Michael; Koch, Andreas; Stevens, Axel P.; Thasler, Wolfgang E.; Müller, Martina; Oefner, Peter J.; Bosserhoff, Anja-Katrin; Hellerbrand, Claus

2013-01-01

To study expression and function of methylthioadenosine phosphorylase (MTAP), the rate-limiting enzyme in the methionine and adenine salvage pathway, in chronic liver disease. Design MTAP expression was analyzed by qRT-PCR, Western blot and immunohistochemical analysis. Levels of MTA were determined by liquid chromatography-tandem mass spectrometry. Results MTAP was downregulated in hepatocytes in murine fibrosis models and in patients with chronic liver disease, leading to a concomitant increase in MTA levels. In contrast, activated hepatic stellate cells (HSCs) showed strong MTAP expression in cirrhotic livers. However, also MTA levels in activated HSCs were significantly higher than in hepatocytes, and there was a significant correlation between MTA levels and collagen expression in diseased human liver tissue indicating that activated HSCs significantly contribute to elevated MTA in diseased livers. MTAP suppression by siRNA resulted in increased MTA levels, NFκB activation and apoptosis resistance, while overexpression of MTAP caused the opposite effects in HSCs. The anti-apoptotic effect of low MTAP expression and high MTA levels, respectively, was mediated by induced expression of survivin, while inhibition of survivin abolished the anti-apoptotic effect of MTA on HSCs. Treatment with a DNA demethylating agent induced MTAP and reduced survivin expression, while oxidative stress reduced MTAP levels but enhanced survivin expression in HSCs. Conclusion MTAP mediated regulation of MTA links polyamine metabolism with NFκB activation and apoptosis in HSCs. MTAP and MTAP modulating mechanisms appear as promising prognostic markers and therapeutic targets for hepatic fibrosis. PMID:24324622

Supraphysiological doses of performance enhancing anabolic-androgenic steroids exert direct toxic effects on neuron-like cells

PubMed Central

Basile, John R.; Binmadi, Nada O.; Zhou, Hua; Yang, Ying-Hua; Paoli, Antonio; Proia, Patrizia

2013-01-01

Anabolic-androgenic steroids (AAS) are lipophilic hormones often taken in excessive quantities by athletes and bodybuilders to enhance performance and increase muscle mass. AAS exert well known toxic effects on specific cell and tissue types and organ systems. The attention that androgen abuse has received lately should be used as an opportunity to educate both athletes and the general population regarding their adverse effects. Among numerous commercially available steroid hormones, very few have been specifically tested for direct neurotoxicity. We evaluated the effects of supraphysiological doses of methandienone and 17-α-methyltestosterone on sympathetic-like neuron cells. Vitality and apoptotic effects were analyzed, and immunofluorescence staining and western blot performed. In this study, we demonstrate that exposure of supraphysiological doses of methandienone and 17-α-methyltestosterone are toxic to the neuron-like differentiated pheochromocytoma cell line PC12, as confirmed by toxicity on neurite networks responding to nerve growth factor and the modulation of the survival and apoptosis-related proteins ERK, caspase-3, poly (ADP-ribose) polymerase and heat-shock protein 90. We observe, in contrast to some previous reports but in accordance with others, expression of the androgen receptor (AR) in neuron-like cells, which when inhibited mitigated the toxic effects of AAS tested, suggesting that the AR could be binding these steroid hormones to induce genomic effects. We also note elevated transcription of neuritin in treated cells, a neurotropic factor likely expressed in an attempt to resist neurotoxicity. Taken together, these results demonstrate that supraphysiological exposure to the AAS methandienone and 17-α-methyltestosterone exert neurotoxic effects by an increase in the activity of the intrinsic apoptotic pathway and alterations in neurite networks. PMID:23675320

Evaluation of synergistic anticandidal and apoptotic effects of ferulic acid and caspofungin against Candida albicans.

PubMed

Canturk, Zerrin

2018-01-01

This study aimed to investigate the synergy between anticandidal and apoptotic effects of ferulic acid and caspofungin against Candida albicans and Candida glabrata, with the help of a quantitative checkerboard microdilution assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) as a viability dye. Apoptotic effects of caspofungin and ferulic acid concentrations (alone and combined) were analyzed for C. albicans and C. glabrata based on annexin V-propidium iodide binding capacities using flow cytometric analysis. C. albicans showed a synergistic effect, represented by a fractional inhibitory concentration index of < 0.5, but C. glabrata showed no synergistic effect (fractional inhibitory concentration index > 0.5). Early and late apoptotic effects of caspofungin and ferulic acid concentrations (1 μg/mL and 1000 μg/mL) were calculated as 55.7% and 18.3%, respectively, while their necrotic effects were determined as 5.8% and 51.6%, respectively, using flow cytometric analyses. The apoptotic effects of the combination of caspofungin and ferulic acid at concentrations of 1 μg/mL and 1000 μg/mL on C. albicans and C. glabrata were 73.0% and 48.7%, respectively. Ferulic acid also demonstrated a synergistic effect in combination with caspofungin against C. albicans. Another possibility is to combine the existing anticandidal drug with phytochemicals to enhance the efficacy of anticandidal drug. Copyright © 2017. Published by Elsevier B.V.

Poncirin Induces Apoptosis in AGS Human Gastric Cancer Cells through Extrinsic Apoptotic Pathway by up-Regulation of Fas Ligand.

PubMed

Saralamma, Venu Venkatarame Gowda; Nagappan, Arulkumar; Hong, Gyeong Eun; Lee, Ho Jeong; Yumnam, Silvia; Raha, Suchismita; Heo, Jeong Doo; Lee, Sang Joon; Lee, Won Sup; Kim, Eun Hee; Kim, Gon Sup

2015-09-18

Poncirin, a natural bitter flavanone glycoside abundantly present in many species of citrus fruits, has various biological benefits such as anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer activities. The anti-cancer mechanism of Poncirin remains elusive to date. In this study, we investigated the anti-cancer effects of Poncirin in AGS human gastric cancer cells (gastric adenocarcinoma). The results revealed that Poncirin could inhibit the proliferation of AGS cells in a dose-dependent manner. It was observed Poncirin induced accumulation of sub-G1 DNA content, apoptotic cell population, apoptotic bodies, chromatin condensation, and DNA fragmentation in a dose-dependent manner in AGS cells. The expression of Fas Ligand (FasL) protein was up-regulated dose dependently in Poncirin-treated AGS cells Moreover, Poncirin in AGS cells induced activation of Caspase-8 and -3, and subsequent cleavage of poly(ADP-ribose) polymerase (PARP). Inhibitor studies' results confirm that the induction of caspase-dependent apoptotic cell death in Poncirin-treated AGS cells was led by the Fas death receptor. Interestingly, Poncirin did not show any effect on mitochondrial membrane potential (ΔΨm), pro-apoptotic proteins (Bax and Bak) and anti-apoptotic protein (Bcl-xL) in AGS-treated cells followed by no activation in the mitochondrial apoptotic protein caspase-9. This result suggests that the mitochondrial-mediated pathway is not involved in Poncirin-induced cell death in gastric cancer. These findings suggest that Poncirin has a potential anti-cancer effect via extrinsic pathway-mediated apoptosis, possibly making it a strong therapeutic agent for human gastric cancer.

Metformin combined with sodium dichloroacetate promotes B leukemic cell death by suppressing anti-apoptotic protein Mcl-1

PubMed Central

Melloni, Elisabetta; Gilli, Paola; Bertolasi, Valerio; Casciano, Fabio; Rigolin, Gian Matteo; Zauli, Giorgio; Secchiero, Paola

2016-01-01

Metformin and the mitochondrial targeting dichloroacetate (DCA) have recently received attention due to their ability to inhibit anaerobic glycolysis, which renders most cancer cells resistant to apoptosis induction. We observed that Metformin alone exhibited a dose-dependent anti-leukemic activity in both B leukemic cell lines and primary B-chronic lymphocytic leukemia (B-CLL) patients' cells and its anti-leukemic activity was enhanced when used in combination with DCA. In order to overcome the problems of poor bioavailability and cellular uptake, which limit DCA efficacy, we have designed and synthetized cocrystals consisting of Metformin and DCA (Met-DCA) at different stoichiometric ratios. Of note, the MetH2++•2DCA− cocrystal exhibited enhanced in vitro anti-leukemic activity, with respect to the treatment with the mix consisting of Metformin plus DCA. In particular, the treatment with the cocrystal MetH2++•2DCA− induced a synergistic apoptotic cell death coupled to a marked down-modulation of the anti-apoptotic Mcl-1 protein. Taken together, our data emphasize that innovative compounds based on Metformin-DCA combination merit to be further evaluated as chemotherapeutic agents for the treatment of B-CLL. PMID:26959881

The basic helix-loop-helix transcription factor Nex-1/Math-2 promotes neuronal survival of PC12 cells by modulating the dynamic expression of anti-apoptotic and cell cycle regulators

PubMed Central

Uittenbogaard, Martine; Chiaramello, Anne

2006-01-01

The basic helix-loop-helix transcription factor Nex1/Math-2 belongs to the NeuroD subfamily, which plays a critical role during neuronal differentiation and maintenance of the differentiated state. Previously, we demonstrated that Nex1 is a key regulatory component of the nerve growth factor (NGF) pathway. Further supporting this hypothesis, this study shows that Nex1 has survival-inducing properties similar to NGF, as Nex1-overexpressing PC12 cells survive in the absence of trophic factors. We dissected the molecular mechanism by which Nex1 confers neuroprotection upon serum removal and found that constitutive expression of Nex1 maintained the expression of specific G1 phase cyclin-dependent kinase inhibitors and concomitantly induced a dynamic expression profile of key anti-apoptotic regulators. This study provides the first evidence of the underlying mechanism by which a member of the NeuroD-subfamily promotes an active anti-apoptotic program essential to the survival of neurons. Our results suggest that the survival program may be viewed as an integral component of the intrinsic programming of the differ entiated state. PMID:15659228

The LIM Protein Zyxin Binds CARP-1 and Promotes Apoptosis

PubMed Central

Hervy, Martial; Hoffman, Laura M.; Jensen, Christopher C.; Smith, Mark; Beckerle, Mary C.

2010-01-01

Zyxin is a dual-function LIM domain protein that regulates actin dynamics in response to mechanical stress and shuttles between focal adhesions and the cell nucleus. Here we show that zyxin contributes to UV-induced apoptosis. Exposure of wild-type fibroblasts to UV-C irradiation results in apoptotic cell death, whereas cells harboring a homozygous disruption of the zyxin gene display a statistically significant survival advantage. To gain insight into the molecular mechanism by which zyxin promotes apoptotic signaling, we expressed an affinity-tagged zyxin variant in zyxin-null cells and isolated zyxin-associated proteins from cell lysates under physiological conditions. A 130-kDa protein that was co-isolated with zyxin was identified by microsequence analysis as the Cell Cycle and Apoptosis Regulator Protein-1 (CARP-1). CARP-1 associates with the LIM region of zyxin. Zyxin lacking the CARP-1 binding region shows reduced proapoptotic activity in response to UV-C irradiation. We demonstrate that CARP-1 is a nuclear protein. Zyxin is modified by phosphorylation in cells exposed to UV-C irradiation, and nuclear accumulation of zyxin is induced by UV-C exposure. These findings highlight a novel mechanism for modulating the apoptotic response to UV irradiation. PMID:20852740

Chondroprotective and anti-inflammatory role of melanocortin peptides in TNF-α activated human C-20/A4 chondrocytes

PubMed Central

Kaneva, Magdalena K; Kerrigan, Mark JP; Grieco, Paolo; Curley, G Paul; Locke, Ian C; Getting, Stephen J

2012-01-01

BACKGROUND AND PURPOSE Melanocortin MC1 and MC3 receptors, mediate the anti-inflammatory effects of melanocortin peptides. Targeting these receptors could therefore lead to development of novel anti-inflammatory therapeutic agents. We investigated the expression of MC1 and MC3 receptors on chondrocytes and the role of α-melanocyte-stimulating hormone (α-MSH) and the selective MC3 receptor agonist, [DTRP8]-γ-MSH, in modulating production of inflammatory cytokines, tissue-destructive proteins and induction of apoptotic pathway(s) in the human chondrocytic C-20/A4 cells. EXPERIMENTAL APPROACH Effects of α-MSH, [DTRP8]-γ-MSH alone or in the presence of the MC3/4 receptor antagonist, SHU9119, on TNF-α induced release of pro-inflammatory cytokines, MMPs, apoptotic pathway(s) and cell death in C-20/A4 chondrocytes were investigated, along with their effect on the release of the anti-inflammatory cytokine IL-10. KEY RESULTS C-20/A4 chondrocytes expressed functionally active MC1,3 receptors. α-MSH and [DTRP8]-γ-MSH treatment, for 30 min before TNF-α stimulation, provided a time-and-bell-shaped concentration-dependent decrease in pro-inflammatory cytokines (IL-1β, IL-6 and IL-8) release and increased release of the chondroprotective and anti-inflammatory cytokine, IL-10, whilst decreasing expression of MMP1, MMP3, MMP13 genes.α-MSH and [DTRP8]-γ-MSH treatment also inhibited TNF-α-induced caspase-3/7 activation and chondrocyte death. The effects of [DTRP8]-γ-MSH, but not α-MSH, were abolished by the MC3/4 receptor antagonist, SHU9119. CONCLUSION AND IMPLICATIONS Activation of MC1/MC3 receptors in C-20/A4 chondrocytes down-regulated production of pro-inflammatory cytokines and cartilage-destroying proteinases, inhibited initiation of apoptotic pathways and promoted release of chondroprotective and anti-inflammatory cytokines. Developing small molecule agonists to MC1/MC3 receptors could be a viable approach for developing chondroprotective and anti-inflammatory therapies in rheumatoid and osteoarthritis. PMID:22471953

Intravenous apoptotic cell infusion as a cell-based therapy toward improving hematopoietic cell transplantation outcome.

PubMed

Saas, Philippe; Gaugler, Béatrice; Perruche, Sylvain

2010-10-01

Allogeneic hematopoietic cell transplantation (AHCT) is an efficient therapy for different malignant and nonmalignant hematological diseases. However, the use of this therapeutic approach is still limited by some severe toxic side effects, mainly graft-versus-host disease (GvHD). Today, the risk of fatal GvHD restrains the wider application of AHCT to many patients in need of an effective therapy for their high-risk hematologic malignancies. Thus, new strategies, including cell-based therapy approaches, are required. We propose to use intravenous donor apoptotic leukocyte infusion to improve AHCT outcome. In experimental AHCT models, we demonstrated that intravenous apoptotic leukocyte infusion, simultaneously with allogeneic bone marrow grafts, favors hematopoietic engraftment, prevents allo-immunization, and delays acute GvHD onset. Here, we review the different mechanisms and the potential beneficial effects associated with the immunomodulatory properties of apoptotic cells in the AHCT setting. © 2010 New York Academy of Sciences.

Estradiol increases the expression of TNF-α and TNF receptor 1 in lactotropes.

PubMed

Zaldivar, Verónica; Magri, María Laura; Zárate, Sandra; Jaita, Gabriela; Eijo, Guadalupe; Radl, Daniela; Ferraris, Jimena; Pisera, Daniel; Seilicovich, Adriana

2011-01-01

Estrogens are recognized modulators of pituitary cell renewal, sensitizing cells to mitogenic and apoptotic signals. Tumor necrosis factor-α (TNF-α) is a proinflammatory cytokine that plays an important role in tissue homeostasis modulating cell proliferation, differentiation and death. We previously demonstrated that TNF-α-induced apoptosis of anterior pituitary cells from female rats is estrogen-dependent and predominant in cells from rats at proestrus when estradiol levels are the highest. Considering that one of the mechanisms involved in the apoptotic action of estrogens can result from increased expression of cytokines and/or their receptors, the aim of the present study was to evaluate the effect of estrogens on the expression of TNF-α and its receptor, TNF receptor 1 (TNFR1), in anterior pituitary cells. TNFR1 expression, determined by Western blot, was higher in anterior pituitary glands from rats at proestrus than at diestrus. Incubation of anterior pituitary cells from ovariectomized rats with 17β-estradiol enhanced TNFR1 protein expression. As determined by double immunocytochemistry, the expression of TNF-α and TNFR1 was detected in prolactin-, GH-, LH- and ACTH-bearing cells. 17β-estradiol increased the percentage of TNF-α and TNFR1-immunoreactive lactotropes but did not modify the number of GH-bearing cells expressing TNF-α or TNFR1. Our results demonstrate that estradiol increases the expression of TNF-α and TNFR1 in anterior pituitary cells, especially in lactotropes. The sensitizing action of estrogens to proapoptotic stimuli at proestrus in the anterior pituitary gland may involve changes in the expression of the TNF-α/TNFR1 system. Copyright © 2011 S. Karger AG, Basel.

Mitochondrial targeted curcumin exhibits anticancer effects through disruption of mitochondrial redox and modulation of TrxR2 activity.

PubMed

Jayakumar, Sundarraj; Patwardhan, Raghavendra S; Pal, Debojyoti; Singh, Babita; Sharma, Deepak; Kutala, Vijay Kumar; Sandur, Santosh Kumar

2017-12-01

Mitocurcumin is a derivative of curcumin, which has been shown to selectively enter mitochondria. Here we describe the anti-tumor efficacy of mitocurcumin in lung cancer cells and its mechanism of action. Mitocurcumin, showed 25-50 fold higher efficacy in killing lung cancer cells as compared to curcumin as demonstrated by clonogenic assay, flow cytometry and high throughput screening assay. Treatment of lung cancer cells with mitocurcumin significantly decreased the frequency of cancer stem cells. Mitocurcumin increased the mitochondrial reactive oxygen species (ROS), decreased the mitochondrial glutathione levels and induced strand breaks in the mitochondrial DNA. As a result, we observed increased BAX to BCL-2 ratio, cytochrome C release into the cytosol, loss of mitochondrial membrane potential and increased caspase-3 activity suggesting that mitocurcumin activates the intrinsic apoptotic pathway. Docking studies using mitocurcumin revealed that it binds to the active site of the mitochondrial thioredoxin reductase (TrxR2) with high affinity. In corroboration with the above finding, mitocurcumin decreased TrxR activity in cell free as well as the cellular system. The anti-cancer activity of mitocurcumin measured in terms of apoptotic cell death and the decrease in cancer stem cell frequency was accentuated by TrxR2 overexpression. This was due to modulation of TrxR2 activity to NADPH oxidase like activity by mitocurcumin, resulting in higher ROS accumulation and cell death. Thus, our findings reveal mitocurcumin as a potent anticancer agent with better efficacy than curcumin. This study also demonstrates the role of TrxR2 and mitochondrial DNA damage in mitocurcumin mediated killing of cancer cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Hydroxyl radical mediates cisplatin-induced apoptosis in human hair follicle dermal papilla cells and keratinocytes through Bcl-2-dependent mechanism.

PubMed

Luanpitpong, Sudjit; Nimmannit, Ubonthip; Chanvorachote, Pithi; Leonard, Stephen S; Pongrakhananon, Varisa; Wang, Liying; Rojanasakul, Yon

2011-08-01

Induction of massive apoptosis of hair follicle cells by chemotherapy has been implicated in the pathogenesis of chemotherapy-induced alopecia (CIA), but the underlying mechanisms of regulation are not well understood. The present study investigated the apoptotic effect of cisplatin in human hair follicle dermal papilla cells and HaCaT keratinocytes, and determined the identity and role of specific reactive oxygen species (ROS) involved in the process. Treatment of the cells with cisplatin induced ROS generation and a parallel increase in caspase activation and apoptotic cell death. Inhibition of ROS generation by antioxidants inhibited the apoptotic effect of cisplatin, indicating the role of ROS in the process. Studies using specific ROS scavengers further showed that hydroxyl radical, but not hydrogen peroxide or superoxide anion, is the primary oxidative species responsible for the apoptotic effect of cisplatin. Electron spin resonance studies confirmed the formation of hydroxyl radicals induced by cisplatin. The mechanism by which hydroxyl radical mediates the apoptotic effect of cisplatin was shown to involve down-regulation of the anti-apoptotic protein Bcl-2 through ubiquitin-proteasomal degradation. Bcl-2 was also shown to have a negative regulatory role on hydroxyl radical. Together, our results indicate an essential role of hydroxyl radical in cisplatin-induced cell death of hair follicle cells through Bcl-2 regulation. Since CIA is a major side effect of cisplatin and many other chemotherapeutic agents with no known effective treatments, the knowledge gained from this study could be useful in the design of preventive treatment strategies for CIA through localized therapy without compromising the chemotherapy efficacy.

The delta opioid peptide D-Alanine 2, Leucine 5 Enkephaline (DADLE)-induces neuroprotection through cross-talk between the UPR and pro-survival MAPK-NGF-Bcl2 signaling pathways via modulation of several micro-RNAs in SH-SY5Y cells subjected to ER stress.

PubMed

Moghal, Erfath Thanjeem Begum; Venkatesh, Katari; Sen, Dwaipayan

2018-05-01

Parkinson's disease (PD) is the second most progressive neurodegenerative disease characterized by the loss of dopaminergic neurons and accumulation of misfolded proteins in endoplasmic reticulum (ER) leading to activation of the unfolded protein response (UPR). In the present study, we aimed to determine the potential survival effect of the delta opioid neuro-peptide D-Alanine 2, Leucine 5 Enkephaline (DADLE), and its mechanism in dopaminergic SH-SY5Y cells which were subjected to ER stress. In this cellular model of PD, enhanced cell survivability was observed on DADLE treatment (but not with μ and κ opioid agonists) along with concomitant down regulation of the UPR stress sensors and protein aggregates. The study found increased phosphorylation of MEK-1, which leads to activation of MAP kinase as well as enhanced expression of the pro-survival gene nerve growth factor and anti-apoptotic marker Bcl2. DADLE treatment could also significantly inhibit expression of the pro-apoptotic marker BIM. Next-generation sequence analysis revealed 93 micro (mi) RNAs to be differentially regulated following DADLE treatment in cells subjected to ER stress. Pathway prediction and previously published reports revealed that out of these 93 miRNAs, 34 can play a role in promoting cell survival. Specific modulation of two such miRNAs, namely miR-30c-2-3p and miR-200c, could partially reverse the positive survival effect induced by DADLE. Apart from the known miRNAs, various novel miRNAs were also observed following DADLE treatment which could also play a role in enhancing the survival of SH-SY5Y cells under ER stress. © 2018 International Federation for Cell Biology.

Bicuculline reverts the neuroprotective effects of meloxicam in an oxygen and glucose deprivation (OGD) model of organotypic hippocampal slice cultures.

PubMed

Landucci, Elisa; Llorente, Irene L; Anuncibay-Soto, Berta; Pellegrini-Giampietro, Domenico E; Fernández-López, Arsenio

2018-06-24

We previously demonstrated that the non-steroidal anti-inflammatory agent meloxicam has neuroprotective effects in an oxygen and glucose deprivation model (OGD) of rat organotypic hippocampal slice cultures. We wondered if GABAergic transmission changed the neuroprotective effects of meloxicam and if meloxicam was able to modulate endoplasmic reticulum stress (ER stress) in this model. Mortality was measured using propidium iodide. Western blot assays were performed to measure levels of cleaved and non-cleaved caspase-3 to quantify apoptosis, while levels of GRP78, GRP94 and phosphorylated eIF2α were used to detect unfolded protein response (UPR). Transcript levels of GRP78, GRP94 and GABAergic receptor α, β, and γ subunits were measured by real-time quantitative polymerase chain reaction (qPCR). In the present study, we show that the presence of meloxicam in a 30 min OGD assay, followed by 24 h of normoxic conditions, presented an antiapoptotic effect. The simultaneous presence of the GABA A receptor antagonist, bicuculline, in combination with meloxicam blocked the neuroprotective effect provided by the latter. However, in light of its effects on caspase 3 and PARP, bicuculline did not seem to promote the apoptotic pathway. Our results also showed that meloxicam modified the unfolded protein response (UPR), as well as the transcriptional response of different genes, including the GABA A receptor, alpha1, beta3 and gamma2 subunits. We concluded that meloxicam has a neuroprotective anti-apoptotic action, is able to enhance the UPR independently of the systemic anti-inflammatory response and its neuroprotective effect can be inhibited by blocking GABA A receptors. Copyright © 2018. Published by Elsevier Ltd.

Bromelain nanoparticles protect against 7,12-dimethylbenz[a]anthracene induced skin carcinogenesis in mouse model.

PubMed

Bhatnagar, Priyanka; Pant, Aditya B; Shukla, Yogeshwer; Chaudhari, Bhushan; Kumar, Pradeep; Gupta, Kailash C

2015-04-01

Conventional cancer chemotherapy leads to severe side effects, which limits its use. Nanoparticles (NPs) based delivery systems offer an effective alternative. Several evidences highlight the importance of Bromelain (BL), a proteolytic enzyme, as an anti-tumor agent which however has been limited due to the requirement of high doses at the tumor site. Therefore, we illustrate the development of BL loaded poly (lactic-co-glycolic acid) NPs that show enhanced anti-tumor effects compared to free BL. The formulated NPs with a mean particle size of 130.4 ± 8.81 nm exhibited sustained release of BL. Subsequent investigation revealed enhanced anti-tumor ability of NPs in 2-stage skin tumorigenesis mice model. Reduction in average number of tumors (∼ 2.3 folds), delay in tumorigenesis (∼ 2 weeks), percent tumorigenesis (∼ 4 folds), and percent mortality rate as well as a reduction in the average tumor volume (∼ 2.5 folds) in mice as compared to free BL were observed. The NPs were found to be superior in exerting chemopreventive effects over chemotherapeutic effects at 10 fold reduced dose than free BL, validated by the enhanced ability of NPs (∼ 1.8 folds) to protect the DNA from induced damage. The effects were also supported by histopathological evaluations. NPs were also capable of modulating the expression of pro-apoptotic (P53, Bax) and anti-apoptotic (Bcl2) proteins. Therefore, our findings demonstrate that developed NPs formulation could be used to improve the efficacy of chemotherapy by exerting chemo-preventive effects against induced carcinogenesis at lower dosages. Copyright © 2015 Elsevier B.V. All rights reserved.

Neurodegenerative changes and apoptosis induced by intrauterine and extrauterine exposure of radiofrequency radiation.

PubMed

Güler, Göknur; Ozgur, Elcin; Keles, Hikmet; Tomruk, Arin; Vural, Sevil Atalay; Seyhan, Nesrin

2016-09-01

Adverse health effects of radiofrequency radiation (RFR) on the ongoing developmental stages of children from conception to childhood are scientifically anticipated subject. This study was performed to identify the effects of global system for mobile communications (GSM) modulated mobile phone like RFR in 1800MHz frequency on oxidative DNA damage and lipid peroxidation beside the apoptotic cell formation, using histopathological and immunohistochemical methods in the brain tissue of 1-month-old male and female New Zealand White rabbits that were exposed to these fields at their mother's womb and after the birth. Oxidative DNA damage and lipid peroxidation levels were investigated by measuring the 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) levels, respectively. Histopathological changes were observed using by hematoxylin and eosin (HE) staining. Apoptotic cells were detected in the examined organs by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining. For both male and female infants; 8-OHdG levels increased in the group exposed to RFR in both intrauterine and extrauterine periods compared to the infants that were never exposed to RFR and the ones were exposed when they reached one month of age (p<0.05). MDA results were different for male and female rabbits. There was no difference between all female infant groups (p>0.05), while only intrauterine exposure significantly causes MDA level increase for the male infants. HE staining revealed mild lessions in neuronal necrobiosis in brain tissues of female rabbits that had only intaruterine exposure and male rabbits had only extrauterine exposure. Gliosis were mildly positive in brain tissues of rabbits that are exposed only intrauterine period, also the group exposed both intrauterine and extrauterine periods. However, there was no apoptotic change detected by TUNEL staining in the brain tissues of all groups. Copyright © 2015 Elsevier B.V. All rights reserved.

Neuroprotection by JM-20 against oxygen-glucose deprivation in rat hippocampal slices: Involvement of the Akt/GSK-3β pathway.

PubMed

Ramírez-Sánchez, Jeney; Simões Pires, Elisa Nicoloso; Nuñez-Figueredo, Yanier; Pardo-Andreu, Gilberto L; Fonseca-Fonseca, Luis Arturo; Ruiz-Reyes, Alberto; Ochoa-Rodríguez, Estael; Verdecia-Reyes, Yamila; Delgado-Hernández, René; Souza, Diogo O; Salbego, Christianne

2015-11-01

Cerebral ischemia is the third most common cause of death and a major cause of disability worldwide. Beyond a shortage of essential metabolites, ischemia triggers many interconnected pathophysiological events, including excitotoxicity, oxidative stress, inflammation and apoptosis. Here, we investigated the neuroprotective mechanisms of JM-20, a novel synthetic molecule, focusing on the phosphoinositide-3-kinase (PI3K)/Akt survival pathway and glial cell response as potential targets of JM-20. For this purpose, we used organotypic hippocampal slice cultures exposed to oxygen-glucose deprivation (OGD) to achieve ischemic/reperfusion damage in vitro. Treatment with JM-20 at 0.1 and 10 μM reduced PI incorporation (indicative of cell death) after OGD. OGD decreased the phosphorylation of Akt (pro-survival) and GSK 3β (pro-apoptotic), resulting in respective inhibition and activation of these proteins. Treatment with JM20 prevented the reduced phosphorylation of these proteins after OGD, representing a shift from pro-apoptotic to pro-survival signaling. The OGD-induced activation of caspase-3 was also attenuated by JM-20 treatment at 10 μM. Moreover, in cultures treated with JM-20 and exposed to OGD conditioning, we observed a decrease in activated microglia, as well as a decrease in interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α release into the culture medium, while the level of the anti-inflammatory IL-10 increased. GFAP immunostaining and IB4 labeling showed that JM-20 treatment significantly augmented GFAP immunoreactivity after OGD, when compared with cultures exposed to OGD only, suggesting the activation of astroglial cells. Our results confirm that JM-20 has a strong neuroprotective effect against ischemic injury and suggest that the mechanisms involved in this effect may include the modulation of reactive astrogliosis, as well as neuroinflammation and the anti-apoptotic cell signaling pathway. Copyright © 2015 Elsevier Ltd. All rights reserved.

PI3K and Bcl-2 inhibition primes glioblastoma cells to apoptosis through downregulation of Mcl-1 and Phospho-BAD.

PubMed

Pareja, Fresia; Macleod, David; Shu, Chang; Crary, John F; Canoll, Peter D; Ross, Alonzo H; Siegelin, Markus D

2014-07-01

Glioblastoma multiforme (GBM) is a highly malignant human brain neoplasm with limited therapeutic options. GBMs display a deregulated apoptotic pathway with high levels of the antiapoptotic Bcl-2 family of proteins and overt activity of the phosphatidylinositol 3-kinase (PI3K) signaling pathway. Therefore, combined interference of the PI3K pathway and the Bcl-2 family of proteins is a reasonable therapeutic strategy. ABT-263 (Navitoclax), an orally available small-molecule Bcl-2 inhibitor, and GDC-0941, a PI3K inhibitor, were used to treat established glioblastoma and glioblastoma neurosphere cells, alone or in combination. Although GDC-0941 alone had a modest effect on cell viability, treatment with ABT-263 displayed a marked reduction of cell viability and induction of apoptotic cell death. Moreover, combinatorial therapy using ABT-263 and GDC-0941 showed an enhanced effect, with a further decrease in cellular viability. Furthermore, combination treatment abrogated the ability of stem cell-like glioma cells to form neurospheres. ABT-263 and GDC-0941, in combination, resulted in a consistent and significant increase of Annexin V positive cells and loss of mitochondrial membrane potential compared with either monotherapy. The combination treatment led to enhanced cleavage of both initiator and effector caspases. Mechanistically, GDC-0941 depleted pAKT (Serine 473) levels and suppressed Mcl-1 protein levels, lowering the threshold for the cytotoxic actions of ABT-263. GDC-0941 decreased Mcl-1 in a posttranslational manner and significantly decreased the half-life of Mcl-1 protein. Ectopic expression of human Mcl-1 mitigated apoptotic cell death induced by the drug combination. Furthermore, GDC-0941 modulated the phosphorylation status of BAD, thereby further enhancing ABT-263-mediated cell death. Combination therapy with ABT-263 and GDC-0941 has novel therapeutic potential by specifically targeting aberrantly active, deregulated pathways in GBM, overcoming endogenous resistance to apoptosis. ©2014 American Association for Cancer Research.

Apoptotic cells subjected to cold/warming exposure disorganize apoptotic microtubule network and undergo secondary necrosis.

PubMed

Oropesa-Ávila, Manuel; Fernández-Vega, Alejandro; de la Mata, Mario; Garrido-Maraver, Juan; Cotán, David; Paz, Marina Villanueva; Pavón, Ana Delgado; Cordero, Mario D; Alcocer-Gómez, Elizabet; de Lavera, Isabel; Lema, Rafael; Zaderenko, Ana Paula; Sánchez-Alcázar, José A

2014-09-01

Apoptotic microtubule network (AMN) is organized during apoptosis, forming a cortical structure beneath the plasma membrane which plays a critical role in preserving cell morphology and plasma membrane integrity. The aim of this study was to examine the effect of cold/warming exposure on apoptotic microtubules and plasma membrane integrity during the execution phase of apoptosis. We demonstrated in camptothecin-induced apoptotic H460 cells that cold/warming exposure disorganized apoptotic microtubules and allowed the access of active caspases to the cellular cortex and the cleavage of essential proteins in the preservation of plasma membrane permeability. Cleavage of cellular cortex and plasma membrane proteins, such as α-spectrin, paxilin, focal adhesion kinase and calcium ATPase pump (PMCA-4) involved in cell calcium extrusion resulted in increased plasma permeability and calcium overload leading apoptotic cells to secondary necrosis. The essential role of caspase-mediated cleavage in this process was demonstrated because the addition of the pan-caspase inhibitor z-VAD during cold/warming exposure that induces AMN depolymerization avoided the cleavage of cortical and plasma membrane proteins and prevented apoptotic cells to undergo secondary necrosis. Likewise, apoptotic microtubules stabilization by taxol during cold/warming exposure also prevented cellular cortex and plasma membrane protein cleavage and secondary necrosis. Furthermore, microtubules stabilization or caspase inhibition during cold/warming exposure was also critical for proper phosphatidylserine externalization and apoptotic cell clearance by macrophages. These results indicate that cold/warming exposure of apoptotic cells induces secondary necrosis which can be prevented by both, microtubule stabilization or caspase inhibition.

The effect of spaceflight on mouse olfactory bulb volume, neurogenesis, and cell death indicates the protective effect of novel environment.

PubMed

Latchney, Sarah E; Rivera, Phillip D; Mao, Xiao W; Ferguson, Virginia L; Bateman, Ted A; Stodieck, Louis S; Nelson, Gregory A; Eisch, Amelia J

2014-06-15

Space missions necessitate physiological and psychological adaptations to environmental factors not present on Earth, some of which present significant risks for the central nervous system (CNS) of crewmembers. One CNS region of interest is the adult olfactory bulb (OB), as OB structure and function are sensitive to environmental- and experience-induced regulation. It is currently unknown how the OB is altered by spaceflight. In this study, we evaluated OB volume and neurogenesis in mice shortly after a 13-day flight on Space Shuttle Atlantis [Space Transport System (STS)-135] relative to two groups of control mice maintained on Earth. Mice housed on Earth in animal enclosure modules that mimicked the conditions onboard STS-135 (AEM-Ground mice) had greater OB volume relative to mice maintained in standard housing on Earth (Vivarium mice), particularly in the granule (GCL) and glomerular (GL) cell layers. AEM-Ground mice also had more OB neuroblasts and fewer apoptotic cells relative to Vivarium mice. However, the AEM-induced increase in OB volume and neurogenesis was not seen in STS-135 mice (AEM-Flight mice), suggesting that spaceflight may have negated the positive effects of the AEM. In fact, when OB volume of AEM-Flight mice was considered, there was a greater density of apoptotic cells relative to AEM-Ground mice. Our findings suggest that factors present during spaceflight have opposing effects on OB size and neurogenesis, and provide insight into potential strategies to preserve OB structure and function during future space missions. Copyright © 2014 the American Physiological Society.

BAD-dependent regulation of fuel metabolism and K(ATP) channel activity confers resistance to epileptic seizures.

PubMed

Giménez-Cassina, Alfredo; Martínez-François, Juan Ramón; Fisher, Jill K; Szlyk, Benjamin; Polak, Klaudia; Wiwczar, Jessica; Tanner, Geoffrey R; Lutas, Andrew; Yellen, Gary; Danial, Nika N

2012-05-24

Neuronal excitation can be substantially modulated by alterations in metabolism, as evident from the anticonvulsant effect of diets that reduce glucose utilization and promote ketone body metabolism. We provide genetic evidence that BAD, a protein with dual functions in apoptosis and glucose metabolism, imparts reciprocal effects on metabolism of glucose and ketone bodies in brain cells. These effects involve phosphoregulation of BAD and are independent of its apoptotic function. BAD modifications that reduce glucose metabolism produce a marked increase in the activity of metabolically sensitive K(ATP) channels in neurons, as well as resistance to behavioral and electrographic seizures in vivo. Seizure resistance is reversed by genetic ablation of the K(ATP) channel, implicating the BAD-K(ATP) axis in metabolic control of neuronal excitation and seizure responses. Copyright © 2012 Elsevier Inc. All rights reserved.

Estradiol increases the Bax/Bcl-2 ratio and induces apoptosis in the anterior pituitary gland.

PubMed

Zaldivar, Verónica; Magri, María Laura; Zárate, Sandra; Jaita, Gabriela; Eijo, Guadalupe; Radl, Daniela; Ferraris, Jimena; Pisera, Daniel; Seilicovich, Adriana

2009-01-01

Estrogens are recognized as acting as modulators of pituitary cell renewal, sensitizing cells to mitogenic and apoptotic signals, thus participating in anterior pituitary homeostasis during the estrous cycle. The balance of pro- and antiapoptotic proteins of the Bcl-2 family is known to regulate cell survival and apoptosis. In order to understand the mechanisms underlying apoptosis during the estrous cycle, we evaluated the expression of the proapoptotic protein Bax and the antiapoptotic proteins Bcl-2 and Bcl-xL in the anterior pituitary gland in cycling female rats as well as the influence of estradiol on the expression of these proteins in anterior pituitary cells of ovariectomized rats. As determined by Western blot, the expression of Bax was higher in anterior pituitary glands from rats at proestrus than at diestrus I, Bcl-2 protein levels showed no difference and Bcl-xL expression was lower, thus increasing the Bax/Bcl-2 ratio at proestrus. Assessed by annexin V binding and flow cytometry, the percentage of apoptotic anterior pituitary cells was higher in rats at proestrus than at diestrus I. Chronic estrogen treatment in ovariectomized rats enhanced the Bax/Bcl-2 ratio and induced apoptosis. Moreover, incubation of cultured anterior pituitary cells from ovariectomized rats with 17beta-estradiol for 24 h increased the Bax/Bcl-2 ratio, decreased Bcl-xL expression and induced apoptosis. Our results demonstrate that estradiol increases the ratio between proapoptotic and antiapoptotic proteins of the Bcl-2 family. This effect could participate in the sensitizing action of estrogens to proapoptotic stimuli and therefore be involved in the high apoptotic rate observed at proestrus in the anterior pituitary gland.

Interferon-gamma induces apoptosis and augments the expression of Fas and Fas ligand by microglia in vitro.

PubMed

Badie, B; Schartner, J; Vorpahl, J; Preston, K

2000-04-01

Activation of microglia by interferon-gamma (IFN-gamma) has been implicated in a number of central nervous system (CNS) inflammatory disease processes. Because IFN-gamma has also been shown to play a role in programmed cell death, we investigated its cytotoxicity and its effect on the Fas apoptotic pathway in microglia. Flow cytometry was used to quantify the IFN-gamma-mediated apoptotic response and Fas and Fas ligand (FasL) expression in two well-characterized murine microglia cell lines (BV-2 and N9). Nuclear fragmentation, suggestive of apoptosis, was noted within 24 h of incubation of microglia with IFN-gamma (10 U/ml). After a 72-h incubation, almost every BV-2 and N9 microglia, but not GL261 glioma cells, underwent cell death and detached from the culture plates. This cytotoxicity occurred even at low IFN-gamma concentrations (1 U/ml) and was inhibited by BAF, a pan-caspase inhibitor. Incubation of BV-2 and N9 microglia, but not GL261 glioma cells, with IFN-gamma also potentiated the expression of Fas and FasL in a similar dose-response and time-course manner, as seen for the apoptotic response. Whereas Fas expression increased by 100% in both microglia cells, FasL upregulation was more pronounced and increased by as much as 200% in the N9 cells. These findings suggest that in addition to its role as a microglia activator, IFN-gamma may also induce apoptosis of microglia, possibly through simultaneous upregulation of Fas and FasL. Interferon-gamma modulation of the Fas pathway and apoptosis in microglia may be important in the pathogenesis of inflammatory CNS disease processes. Copyright 2000 Academic Press.

Regulatory effect of the AMPK-COX-2 signaling pathway in curcumin-induced apoptosis in HT-29 colon cancer cells.

PubMed

Lee, Yun-Kyoung; Park, Song Yi; Kim, Young-Min; Park, Ock Jin

2009-08-01

AMP-activated protein kinase (AMPK), a highly conserved protein in eukaryotes, functions as a major metabolic switch to maintain energy homeostasis. It also intrinsically regulates the mammalian cell cycle. Moreover, the AMPK cascade has emerged as an important pathway implicated in cancer control. In this study we investigated the effects of curcumin on apoptosis and the regulatory effect of the AMPK-cyclooxygenase-2 (COX-2) pathway in curcumin-induced apoptosis. Curcumin has shown promise as a chemopreventive agent because of its in vivo regression of various animal-model colon cancers. This study focused on exploiting curcumin to apply antitumorigenic effects through modulation of the AMPK-COX-2 cascade. Curcumin exhibited a potent apoptotic effect on HT-29 colon cancer cells at concentrations of 50 micromol/L and above. These apoptotic effects were correlated with the decrease in pAkt and COX-2, as well as the increase in p-AMPK. Cell cycle analysis showed that curcumin induced G(1)-phase arrest. Further study with AMPK synthetic inhibitor Compound C has shown that increased concentrations of Compound C would abolish AMPK expression, accompanied by a marked increase in COX-2 as well as pAkt expression in curcumin-treated HT-29 cells. By inhibiting AMPK with Compound C, we found that curcumin-treated colon cancer cells were no longer undergoing apoptosis; rather, they were proliferative. These results indicate that AMPK is crucial in apoptosis induced by curcumin and further that the pAkt-AMPK-COX-2 cascade or AMPK-pAkt-COX-2 pathway is important in cell proliferation and apoptosis in colon cancer cells.

Mitomycin C-induced apoptosis in cultured human Tenon's capsule fibroblasts.

PubMed

Kim, J W; Kim, S K; Song, I H; Kim, I T

1999-06-01

To investigate the mitomycin C-induced apoptotic cell death of fibroblasts, the primarily cultured human Tenon's capsule fibroblasts were exposed to a clinically used dosage of 0.4 mg/ml of mitomycin C for 5 minutes. TUNEL (TdT-mediated dUTP-biotin nick end labeling) assay and electron microscopic studies were performed to determine the extent of mitomycin C-induced apoptosis. A flow cytometric study was performed to quantify the apoptotic cell population over time. The TUNEL stains were positive and electron microscopy showed features of apoptotic cell death in some fibroblasts 3 and 5 days after treatment. Flow cytometric analysis using Annexin V-propidium iodide double staining detected apoptotic cells 3 days after treatment. These apoptotic cell populations increased at 4 days and were sustained for one week. This study revealed that the clinical effects of mitomycin C on fibroblasts may be mediated not only by antiproliferative but also apoptotic cell death to some degree. Therefore, the apoptotic cell death of fibroblasts induced by mitomycin C should be considered to properly understand the mechanism of wound healing after trabeculectomy with adjunctive mitomycin C.

Concise Review: Apoptotic Cell-Based Therapies-Rationale, Preclinical Results and Future Clinical Developments.

PubMed

Saas, Philippe; Daguindau, Etienne; Perruche, Sylvain

2016-06-01

The objectives of this review are to summarize the experimental data obtained using apoptotic cell-based therapies, and then to discuss future clinical developments. Indeed, apoptotic cells exhibit immunomodulatory properties that are reviewed here by focusing on more recent mechanisms. These immunomodulatory mechanisms are in particular linked to the clearance of apoptotic cells (called also efferocytosis) by phagocytes, such as macrophages, and the induction of regulatory T cells. Thus, apoptotic cell-based therapies have been used to prevent or treat experimental inflammatory diseases. Based on these studies, we have identified critical steps to design future clinical trials. This includes: the administration route, the number and schedule of administration, the appropriate apoptotic cell type to be used, as well as the apoptotic signal. We also have analyzed the clinical relevancy of apoptotic-cell-based therapies in experimental models. Additional experimental data are required concerning the treatment of inflammatory diseases (excepted for sepsis) before considering future clinical trials. In contrast, apoptotic cells have been shown to favor engraftment and to reduce acute graft-versus-host disease (GvHD) in different relevant models of transplantation. This has led to the conduct of a phase 1/2a clinical trial to alleviate GvHD. The absence of toxic effects obtained in this trial may support the development of other clinical studies based on this new cell therapy. Stem Cells 2016;34:1464-1473. © 2016 AlphaMed Press.

Ethyl acetate extract of germinated brown rice attenuates hydrogen peroxide-induced oxidative stress in human SH-SY5Y neuroblastoma cells: role of anti-apoptotic, pro-survival and antioxidant genes.

PubMed

Azmi, Nur Hanisah; Ismail, Norsharina; Imam, Mustapha Umar; Ismail, Maznah

2013-07-17

There are reports of improved metabolic outcomes due to consumption of germinated brown rice (GBR). Many of the functional effects of GBR can be linked to its high amounts of antioxidants. Interestingly, dietary components with high antioxidants have shown promise in the prevention of neurodegenerative diseases like Alzheimer's disease (AD). This effect of dietary components is mostly based on their ability to prevent apoptosis, which is believed to link oxidative damage to pathological changes in AD. In view of the rich antioxidant content of GBR, we studied its potential to modulate processes leading up to AD. The total phenolic content and antioxidant capacity of the ethyl acetate extract of GBR were compared to that of brown rice (BR), and the cytotoxicity of both extracts were determined on human SH-SY5Y neuronal cells using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) Assay. Based on its higher antioxidant potentials, the effect of the GBR extract on morphological changes due to hydrogen peroxide (H₂O₂)-induced oxidative damage in human SH-SY5Y neuronal cells was examined using inverted light microscope and fluorescence microscope by means of acridine orange-propidium iodide (AO/PI) staining. Also, evaluation of the transcriptional regulation of antioxidant and apoptotic genes was carried out using Multiplex Gene Expression System. The ethyl acetate extract of GBR had higher total phenolic content and antioxidant capacity compared to BR. The cytotoxicity results showed that GBR extract did not cause any damage to the human SH-SY5Y neuronal cells at concentrations of up to 20 ppm, and the morphological analyses showed that the GBR extract (up to 10 ppm) prevented H₂O₂-induced apoptotic changes in the cells. Furthermore, multiplex gene expression analyses showed that the protection of the cells by the GBR extract was linked to its ability to induce transcriptional changes in antioxidant (SOD 1, SOD 2 and catalase) and apoptotic (AKT, NF-Kβ, ERK1/2, JNK, p53 and p38 MAPK) genes that tended towards survival. Taken together, the results of our study showed that the ethyl acetate extract of GBR, with high antioxidant potentials, could prevent H₂O₂-induced oxidative damage in SH-SY5Y cells. The potential of GBR and its neuroprotective mechanism in ameliorating oxidative stress-related cytotoxicity is therefore worth exploring further.

Cellular Basis for Learning Impairment in Fragile X Syndrome

DTIC Science & Technology

2014-08-01

oxygen is restored. Induction of the heat shock proteins (HSPs) is one of the first lines of defense against physiological stress , shifting cellular...Haddad, 2001), and aid resistance to glutamate and hypoxic stress in mammals (Zhang et al., 2000). AMPA receptor currents, meanwhile, are also...level in anoxic turtle brain. These include increases in heat shock proteins, anti-apoptotic factors, the MAP kinases, antioxidants and modulation of

MicroRNAs and Glucocorticoid-Induced Apoptosis in Lymphoid Malignancies

PubMed Central

Sionov, Ronit Vogt

2013-01-01

The initial response of lymphoid malignancies to glucocorticoids (GCs) is a critical parameter predicting successful treatment. Although being known as a strong inducer of apoptosis in lymphoid cells for almost a century, the signaling pathways regulating the susceptibility of the cells to GCs are only partly revealed. There is still a need to develop clinical tests that can predict the outcome of GC therapy. In this paper, I discuss important parameters modulating the pro-apoptotic effects of GCs, with a specific emphasis on the microRNA world comprised of small players with big impacts. The journey through the multifaceted complexity of GC-induced apoptosis brings forth explanations for the differential treatment response and raises potential strategies for overcoming drug resistance. PMID:23431463

Pelle Modulates dFoxO-Mediated Cell Death in Drosophila.

PubMed

Wu, Chenxi; Chen, Yujun; Wang, Feng; Chen, Changyan; Zhang, Shiping; Li, Chaojie; Li, Wenzhe; Wu, Shian; Xue, Lei

2015-10-01

Interleukin-1 receptor-associated kinases (IRAKs) are crucial mediators of the IL-1R/TLR signaling pathways that regulate the immune and inflammation response in mammals. Recent studies also suggest a critical role of IRAKs in tumor development, though the underlying mechanism remains elusive. Pelle is the sole Drosophila IRAK homolog implicated in the conserved Toll pathway that regulates Dorsal/Ventral patterning, innate immune response, muscle development and axon guidance. Here we report a novel function of pll in modulating apoptotic cell death, which is independent of the Toll pathway. We found that loss of pll results in reduced size in wing tissue, which is caused by a reduction in cell number but not cell size. Depletion of pll up-regulates the transcription of pro-apoptotic genes, and triggers caspase activation and cell death. The transcription factor dFoxO is required for loss-of-pll induced cell death. Furthermore, loss of pll activates dFoxO, promotes its translocation from cytoplasm to nucleus, and up-regulates the transcription of its target gene Thor/4E-BP. Finally, Pll physically interacts with dFoxO and phosphorylates dFoxO directly. This study not only identifies a previously unknown physiological function of pll in cell death, but also shed light on the mechanism of IRAKs in cell survival/death during tumorigenesis.

Combined venetoclax and alvocidib in acute myeloid leukemia.

PubMed

Bogenberger, James; Whatcott, Clifford; Hansen, Nanna; Delman, Devora; Shi, Chang-Xin; Kim, Wontak; Haws, Hillary; Soh, Katherine; Lee, Ye Sol; Peterson, Peter; Siddiqui-Jain, Adam; Weitman, Steven; Stewart, Keith; Bearss, David; Mesa, Ruben; Warner, Steven; Tibes, Raoul

2017-12-05

More effective treatment options for elderly acute myeloid leukemia (AML) patients are needed as only 25-50% of patients respond to standard-of-care therapies, response duration is typically short, and disease progression is inevitable even with some novel therapies and ongoing clinical trials. Anti-apoptotic BCL-2 family inhibitors, such as venetoclax, are promising therapies for AML. Nonetheless, resistance is emerging. We demonstrate that venetoclax combined with cyclin-dependent kinase (CDK) inhibitor alvocidib is potently synergistic in venetoclax-sensitive and -resistant AML models in vitro , ex vivo and in vivo . Alvocidib decreased MCL-1, and/or increased pro-apoptotic proteins such as BIM or NOXA, often synergistically with venetoclax. Over-expression of BCL-XL diminished synergy, while knock-down of BIM almost entirely abrogated synergy, demonstrating that the synergistic interaction between alvocidib and venetoclax is primarily dependent on intrinsic apoptosis. CDK9 inhibition predominantly mediated venetoclax sensitization, while CDK4/6 inhibition with palbociclib did not potentiate venetoclax activity. Combined, venetoclax and alvocidib modulate the balance of BCL-2 family proteins through complementary, yet variable mechanisms favoring apoptosis, highlighting this combination as a promising therapy for AML or high-risk MDS with the capacity to overcome intrinsic apoptosis mechanisms of resistance. These results support clinical testing of combined venetoclax and alvocidib for the treatment of AML and advanced MDS.

Combined venetoclax and alvocidib in acute myeloid leukemia

PubMed Central

Bogenberger, James; Whatcott, Clifford; Hansen, Nanna; Delman, Devora; Shi, Chang-Xin; Kim, Wontak; Haws, Hillary; Soh, Katherine; Lee, Ye Sol; Peterson, Peter; Siddiqui-Jain, Adam; Weitman, Steven; Stewart, Keith; Bearss, David; Mesa, Ruben; Warner, Steven; Tibes, Raoul

2017-01-01

More effective treatment options for elderly acute myeloid leukemia (AML) patients are needed as only 25–50% of patients respond to standard-of-care therapies, response duration is typically short, and disease progression is inevitable even with some novel therapies and ongoing clinical trials. Anti-apoptotic BCL-2 family inhibitors, such as venetoclax, are promising therapies for AML. Nonetheless, resistance is emerging. We demonstrate that venetoclax combined with cyclin-dependent kinase (CDK) inhibitor alvocidib is potently synergistic in venetoclax-sensitive and -resistant AML models in vitro, ex vivo and in vivo. Alvocidib decreased MCL-1, and/or increased pro-apoptotic proteins such as BIM or NOXA, often synergistically with venetoclax. Over-expression of BCL-XL diminished synergy, while knock-down of BIM almost entirely abrogated synergy, demonstrating that the synergistic interaction between alvocidib and venetoclax is primarily dependent on intrinsic apoptosis. CDK9 inhibition predominantly mediated venetoclax sensitization, while CDK4/6 inhibition with palbociclib did not potentiate venetoclax activity. Combined, venetoclax and alvocidib modulate the balance of BCL-2 family proteins through complementary, yet variable mechanisms favoring apoptosis, highlighting this combination as a promising therapy for AML or high-risk MDS with the capacity to overcome intrinsic apoptosis mechanisms of resistance. These results support clinical testing of combined venetoclax and alvocidib for the treatment of AML and advanced MDS. PMID:29291023

β2-Adrenergic Receptor Knockout Mice Exhibit A Diabetic Retinopathy Phenotype

PubMed Central

Jiang, Youde; Zhang, Qiuhua; Liu, Li; Tang, Jie; Kern, Timothy S.; Steinle, Jena J.

2013-01-01

There is considerable evidence from our lab and others for a functional link between β-adrenergic receptor and insulin receptor signaling pathways in retina. Furthermore, we hypothesize that this link may contribute to lesions similar to diabetic retinopathy in that the loss of adrenergic input observed in diabetic retinopathy may disrupt normal anti-apoptotic insulin signaling, leading to retinal cell death. Our studies included assessment of neural retina function (ERG), vascular degeneration, and Müller glial cells (which express only β1 and β2-adrenergic receptor subtypes). In the current study, we produced β2-adrenergic receptor knockout mice to examine this deletion on retinal neurons and vasculature, and to identify specific pathways through which β2-adrenergic receptor modulates insulin signaling. As predicted from our hypothesis, β2-adrenergic receptor knockout mice display certain features similar to diabetic retinopathy. In addition, loss of β2-adrenergic input resulted in an increase in TNFα, a key inhibitor of insulin receptor signaling. Increased TNFα may be associated with insulin-dependent production of the anti-apoptotic factor, Akt. Since the effects occurred in vivo under normal glucose conditions, we postulate that aspects of the diabetic retinopathy phenotype might be triggered by loss of β2-adrenergic receptor signaling. PMID:23894672

Cyclic AMP efflux inhibitors as potential therapeutic agents for leukemia.

PubMed

Perez, Dominique R; Smagley, Yelena; Garcia, Matthew; Carter, Mark B; Evangelisti, Annette; Matlawska-Wasowska, Ksenia; Winter, Stuart S; Sklar, Larry A; Chigaev, Alexandre

2016-06-07

Apoptotic evasion is a hallmark of cancer. We propose that some cancers may evade cell death by regulating 3'-5'-cyclic adenosine monophosphate (cAMP), which is associated with pro-apoptotic signaling. We hypothesize that leukemic cells possess mechanisms that efflux cAMP from the cytoplasm, thus protecting them from apoptosis. Accordingly, cAMP efflux inhibition should result in: cAMP accumulation, activation of cAMP-dependent downstream signaling, viability loss, and apoptosis. We developed a novel assay to assess cAMP efflux and performed screens to identify inhibitors. In an acute myeloid leukemia (AML) model, several identified compounds reduced cAMP efflux, appropriately modulated pathways that are responsive to cAMP elevation (cAMP-responsive element-binding protein phosphorylation, and deactivation of Very Late Antigen-4 integrin), and induced mitochondrial depolarization and caspase activation. Blocking adenylyl cyclase activity was sufficient to reduce effects of the most potent compounds. These compounds also decreased cAMP efflux and viability of B-lineage acute lymphoblastic leukemia (B-ALL) cell lines and primary patient samples, but not of normal primary peripheral blood mononuclear cells. Our data suggest that cAMP efflux is a functional feature that could be therapeutically targeted in leukemia. Furthermore, because some of the identified drugs are currently used for treating other illnesses, this work creates an opportunity for repurposing.

MLF1 is a proapoptotic antagonist of HOP complex-mediated survival.

PubMed

Sun, Yi; Chao, Jyh-Rong; Xu, Wu; Pourpak, Alan; Boyd, Kelli; Moshiach, Simon; Qi, Guo-Yan; Fu, Amina; Shao, Hua-Rong; Pounds, Stanley; Morris, Stephan W

2017-04-01

In the HAX1/HtrA2-OMI/PARL (HOP) mitochondrial protein complex, anti-apoptotic signals are generated by cleavage and activation of the serine protease HtrA2/OMI by the rhomboid protease PARL upon recruitment of both proteases to inner mitochondrial membrane protein HAX1 (HS1-associated protein X-1). Here we report the negative regulation of the HOP complex by human leukemia-associated myeloid leukemia factor 1 (MLF1). We demonstrate that MLF1 physically and functionally associates with HAX1 and HtrA2. Increased interaction of MLF1 with HAX1 and HtrA2 displaces HtrA2 from the HOP complex and inhibits HtrA2 cleavage and activation, resulting in the apoptotic cell death. Conversely, over-expressed HAX1 neutralizes MLF1's effect and inhibits MLF1-induced apoptosis. Importantly, Mlf1 deletion reverses B- and T-cell lymphopenia and significantly ameliorates the progressive striatal and cerebellar neurodegeneration observed in Hax1 -/- mice, with a doubling of the lifespan of Mlf1 -/- /Hax1 -/- animals compared to Hax1 -/- animals. Collectively, these data indicate that MLF1 serves as a proapoptotic antagonist that interacts with the HOP mitochondrial complex to modulate cell survival. Copyright © 2017 Elsevier B.V. All rights reserved.

Arsenic induces apoptosis in mouse liver is mitochondria dependent and is abrogated by N-acetylcysteine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Santra, Amal; Chowdhury, Abhijit; Ghatak, Subhadip

2007-04-15

Arsenicosis, caused by arsenic contamination of drinking water supplies, is a major public health problem in India and Bangladesh. Chronic liver disease, often with portal hypertension occurs in chronic arsenicosis, contributes to the morbidity and mortality. The early cellular events that initiate liver cell injury due to arsenicosis have not been studied. Our aim was to identify the possible mechanisms related to arsenic-induced liver injury in mice. Liver injury was induced in mice by arsenic treatment. The liver was used for mitochondrial oxidative stress, mitochondrial permeability transition (MPT). Evidence of apoptosis was sought by TUNEL test, caspase assay and histology.more » Pretreatment with N-acetyl-L-cysteine (NAC) was done to modulate hepatic GSH level. Arsenic treatment in mice caused liver injury associated with increased oxidative stress in liver mitochondria and alteration of MPT. Altered MPT facilitated cytochrome c release in the cytosol, activation of caspase 9 and caspase 3 activities and apoptotic cell death. Pretreatment of NAC to arsenic-treated mice abrogated all these alteration suggesting a glutathione (GSH)-dependent mechanism. Oxidative stress in mitochondria and inappropriate MPT are important in the pathogenesis of arsenic induced apoptotic liver cell injury. The phenomenon is GSH dependent and supplementation of NAC might have beneficial effects.« less

FAS apoptotic inhibitory molecule 2 is a stress-induced intrinsic neuroprotective factor in the retina.

PubMed

Pawar, Mercy; Busov, Boris; Chandrasekhar, Aaruran; Yao, Jingyu; Zacks, David N; Besirli, Cagri G

2017-10-01

We report the neuroprotective role of FAS apoptotic inhibitory molecule 2 (FAIM2), an inhibitor of the FAS signaling pathway, during stress-induced photoreceptor apoptosis. Retinal detachment resulted in increased FAIM2 levels in photoreceptors with higher amounts detected at the tips of outer segments. Activation of FAS death receptor via FAS-ligand led to JNK-mediated FAIM2 phosphorylation, decreased proteasome-mediated degradation and increased association with the FAS receptor. Photoreceptor apoptosis was accelerated in Faim2 knockout mice following experimental retinal detachment. We show that FAIM2 is primarily involved in reducing stress-induced photoreceptor cell death but this effect was transient. FAIM2 was found to interact with both p53 and HSP90 following the activation of the FAS death pathway and FAIM2/HSP90 interaction was dependent on the phosphorylation of FAIM2. Lack of FAIM2 led to increased expression of proadeath genes Fas and Ripk1 in the retina under physiologic conditions. These results demonstrate that FAIM2 is an intrinsic neuroprotective factor activated by stress in photoreceptors and delays FAS-mediated photoreceptor apoptosis. Modulation of this pathway to increase FAIM2 expression may be a potential therapeutic option to prevent photoreceptor death.

Silencing of decoy receptor 3 (DcR3) expression by siRNA in pancreatic carcinoma cells induces Fas ligand-mediated apoptosis in vitro and in vivo.

PubMed

Zhou, Jian; Song, Shiduo; He, Songbin; Wang, Zhenxin; Zhang, Bing; Li, Dechun; Zhu, Dongming

2013-09-01

Decoy receptor 3 (DcR3) is abundantly expressed in human tumors and protects cells from a wide range of apoptotic stimuli. In this study, we demonstrate that DcR3 is overexpressed in pancreatic carcinoma cells, and that the pancreatic carcinoma cell lines, Panc-1 and SW1990, are resistant to Fas ligand (FasL)-mediated apoptosis. To further define the function of DcR3 in cell growth and apoptosis, we used small interfering RNA (siRNA) to knockdown the expression of the DcR3 gene in Panc-1 and SW1990 cells. Our results revealed that the silencing of DcR3 expression enhanced the inhibitory effects of FasL and reduced the capabiltiy of the cells for proliferation and colony formation in vitro. In addition, the downregulation of DcR3 modulated the cell apoptotic regulators, Fas-associated death domain (FADD), caspase‑3 and caspase‑8, thus triggering cell apoptosis. Furthermore, the knockdown of DcR3 inhibited the growth of Panc-1 tumor xenografts. Taken together, our findings indicate that DcR3 is important in cancer progression and may be a used as a potential therapeutic target for the gene therapy of pancreatic carcinoma.

Effect of Apoptotic Cell Recognition on Macrophage Polarization and Mycobacterial Persistence

PubMed Central

de Oliveira Fulco, Tatiana; Andrade, Priscila Ribeiro; de Mattos Barbosa, Mayara Garcia; Pinto, Thiago Gomes Toledo; Ferreira, Paula Fernandez; Ferreira, Helen; da Costa Nery, José Augusto; Real, Suzana Côrte; Borges, Valéria Matos; Moraes, Milton Ozório; Sarno, Euzenir Nunes; Sampaio, Elizabeth Pereira

2014-01-01

Intracellular Mycobacterium leprae infection modifies host macrophage programming, creating a protective niche for bacterial survival. The milieu regulating cellular apoptosis in the tissue plays an important role in defining susceptible and/or resistant phenotypes. A higher density of apoptotic cells has been demonstrated in paucibacillary leprosy lesions than in multibacillary ones. However, the effect of apoptotic cell removal on M. leprae-stimulated cells has yet to be fully elucidated. In this study, we investigated whether apoptotic cell removal (efferocytosis) induces different phenotypes in proinflammatory (Mϕ1) and anti-inflammatory (Mϕ2) macrophages in the presence of M. leprae. We stimulated Mϕ1 and Mϕ2 cells with M. leprae in the presence or absence of apoptotic cells and subsequently evaluated the M. leprae uptake, cell phenotype, and cytokine pattern in the supernatants. In the presence of M. leprae and apoptotic cells, Mϕ1 macrophages changed their phenotype to resemble the Mϕ2 phenotype, displaying increased CD163 and SRA-I expression as well as higher phagocytic capacity. Efferocytosis increased M. leprae survival in Mϕ1 cells, accompanied by reduced interleukin-15 (IL-15) and IL-6 levels and increased transforming growth factor beta (TGF-β) and IL-10 secretion. Mϕ1 cells primed with M. leprae in the presence of apoptotic cells induced the secretion of Th2 cytokines IL-4 and IL-13 in autologous T cells compared with cultures stimulated with M. leprae or apoptotic cells alone. Efferocytosis did not alter the Mϕ2 cell phenotype or cytokine secretion profile, except for TGF-β. Based on these data, we suggest that, in paucibacillary leprosy patients, efferocytosis contributes to mycobacterial persistence by increasing the Mϕ2 population and sustaining the infection. PMID:25024361

Leptin signaling and apoptotic effects in human prostate cancer cell lines.

PubMed

Samuel-Mendelsohn, Sigal; Inbar, Michal; Weiss-Messer, Esther; Niv-Spector, Leonora; Gertler, Arieh; Barkey, Ronnie J

2011-06-15

Prostate cancer (PCa) progression is often associated with transactivation of the androgen receptor (AR) by endogenous hormones/growth factors. One such factor affecting growth, proliferation, and apoptostis (pro-/anti-) in various cancers is the adipokine leptin. This research studied leptin-induced signaling and apoptosis in androgen sensitive (LNCaP, PC3/AR) and insensitive (PC3, DU145) PCa cell lines. Signaling was studied by immunoblotting in cells overexpressing leptin receptors (LRb), Janus kinase 2 (JAK2), and kinase negative-HER2-YFP cDNAs. Apoptosis was measured by immunoblotting of apoptotic proteins and by Hoechst staining of condensed DNA. Leptin rapidly induced activation of JAK2, STAT3, and MAPK (ERK1/2) signaling cascades; it may also induce HER2 transactivation via leptin-induced phospho-JAK2. Leptin was then shown to exert clear pro-apoptotic effects, increasing levels of caspase 3, cleavage of its substrate, poly (ADP-ribose) polymerase (PARP) to cleaved PARP(89) , levels of CK 18, a cytoskeletal protein formed during apoptosis, and DNA condensation. Kinase inhibitors indicated that leptin-induced apoptosis is probably mediated by balanced activation of JAK2/STAT3, p38 MAPK, and PKC pathways in PCa cells. A human leptin mutein LRb antagonist, L39A/D40A/F41A, fully inhibited leptin-induced phosphorylation of JAK2, ERK1/2, and Akt/PKB, and partially abrogated effects on apoptotic proteins. In LNCaP and PC3/AR cells, leptin increased AR protein levels in correlation with raised apoptotic markers. Thus, AR may mediate, at least partly, the leptin-induced apoptotic response. Leptin can clearly induce apoptosis in human PCa cell lines. These findings could lead to development of new leptin agonists with enhanced pro-apoptotic effects and targeted for use in human PCa. Copyright © 2010 Wiley-Liss, Inc.

Epigenetic regulation of the TRAIL/Apo2L apoptotic pathway by histone deacetylase inhibitors: an attractive approach to bypass melanoma immunotherapy resistance

PubMed Central

Jazirehi, Ali R; Arle, Dylan

2013-01-01

TNF-related apoptosis-inducing ligand (TRAIL/Apo2L) is a major cytotoxic mechanism employed by cytotoxic T lymphocytes (CTL) and natural killer (NK) cells to eradicate malignant cells. TRAIL/Apo2L interacts with its cognate receptors located on tumor cell surface namely, TRAIL-R1 (DR4), TRAIL-R2 (DR5), TRAIL-R3 (DcR1), TRAIL-R4 (DcR2) and osteoprotegerin (OPG). The exact function of DcR1 and DcR2 remains elusive. TRAIL/Apo2L or agonistic monoclonal antibodies directed against TRAIL/Apo2L death-inducing receptors (DR4, DR5) have become an attractive immunological therapeutic tools in clinical oncology due to their selective killing of tumors and lack of affinity towards healthy cells. Though a potent anti-cancer modality, some cancer cells exhibit inherent or acquired resistance to TRAIL/Apo2L. Postulated resistance mechanisms include up-regulation of c-FLIP, down-regulation of caspase-8, down-regulation/shedding of death receptors and an imbalanced ratio of pro- to anti-apoptotic genes due to aberrant activity of cellular survival signal transduction pathways. The development of resistance has spurred the use of combination therapy, in particular using small molecule sensitizing agents, to restore apoptosis sensitivity. A novel category of such compounds is histone deacetylase inhibitors (HDACi), which block HDACs from removing acetyl groups from histone tails thereby preventing silencing of pro-apoptotic genes and regulating the expression of non-histone proteins (i.e., apoptosis-associated genes), are effective agents in some malignancies. Some HDACi, such as Suberoylanilide Hydroxamic Acid (SAHA), have received FDA approval for cancer treatment. In various melanoma preclinical models, HDACi in conjunction with TRAIL/Apo2L, via modulation of apoptotic machinery, have proven to overcome acquired/inherent resistance to either agent. Here, we discuss recent findings on the role of TRAIL/Apo2L and its agonistic mAbs in melanoma immunotherapy with discussions on potential cellular and molecular events by which HDACi can sensitize metastatic melanoma to TRAIL/Apo2L-mediated immune-therapy, thereby, overcoming resistance. PMID:23885325

SI113, a SGK1 inhibitor, potentiates the effects of radiotherapy, modulates the response to oxidative stress and induces cytotoxic autophagy in human glioblastoma multiforme cells

PubMed Central

Talarico, Cristina; Dattilo, Vincenzo; D'Antona, Lucia; Barone, Agnese; Amodio, Nicola; Belviso, Stefania; Musumeci, Francesca; Abbruzzese, Claudia; Bianco, Cataldo; Trapasso, Francesco; Schenone, Silvia; Alcaro, Stefano; Ortuso, Francesco; Florio, Tullio; Paggi, Marco G.; Perrotti, Nicola; Amato, Rosario

2016-01-01

Glioblastoma multiforme (GBM) is the most aggressive CNS tumor and is characterized by a very high frequency of clinical relapse after therapy and thus by a dismal prognosis, which strongly compromises patients survival. We have recently identified the small molecule SI113, as a potent and selective inhibitor of SGK1, a serine/threonine protein kinase, that modulates several oncogenic signaling cascades. The SI113-dependent SGK1 inhibition induces cell death, blocks proliferation and perturbs cell cycle progression by modulating SGK1-related substrates. SI113 is also able to strongly and consistently block, in vitro and in vivo, growth and survival of human hepatocellular-carcinomas, either used as a single agent or in combination with ionizing radiations. In the present paper we aim to study the effect of SI113 on human GBM cell lines with variable p53 expression. Cell viability, cell death, caspase activation and cell cycle progression were then analyzed by FACS and WB-based assays, after exposure to SI113, with or without oxidative stress and ionizing radiations. Moreover, autophagy and related reticulum stress response were evaluated. We show here, that i) SGK1 is over-expressed in highly malignant gliomas and that the treatment with SI113 leads to ii) significant increase in caspase-mediated apoptotic cell death in GBM cell lines but not in normal fibroblasts; iii)enhancement of the effects of ionizing radiations; iv) modulation of the response to oxidative reticulum stress; v) induction of cytotoxic autophagy. Evidence reported here underlines the therapeutic potential of SI113 in GBM, suggesting a new therapeutic strategy either alone or in combination with radiotherapy. PMID:26908461

SI113, a SGK1 inhibitor, potentiates the effects of radiotherapy, modulates the response to oxidative stress and induces cytotoxic autophagy in human glioblastoma multiforme cells.

PubMed

Talarico, Cristina; Dattilo, Vincenzo; D'Antona, Lucia; Barone, Agnese; Amodio, Nicola; Belviso, Stefania; Musumeci, Francesca; Abbruzzese, Claudia; Bianco, Cataldo; Trapasso, Francesco; Schenone, Silvia; Alcaro, Stefano; Ortuso, Francesco; Florio, Tullio; Paggi, Marco G; Perrotti, Nicola; Amato, Rosario

2016-03-29

Glioblastoma multiforme (GBM) is the most aggressive CNS tumor and is characterized by a very high frequency of clinical relapse after therapy and thus by a dismal prognosis, which strongly compromises patients survival. We have recently identified the small molecule SI113, as a potent and selective inhibitor of SGK1, a serine/threonine protein kinase, that modulates several oncogenic signaling cascades. The SI113-dependent SGK1 inhibition induces cell death, blocks proliferation and perturbs cell cycle progression by modulating SGK1-related substrates. SI113 is also able to strongly and consistently block, in vitro and in vivo, growth and survival of human hepatocellular-carcinomas, either used as a single agent or in combination with ionizing radiations. In the present paper we aim to study the effect of SI113 on human GBM cell lines with variable p53 expression. Cell viability, cell death, caspase activation and cell cycle progression were then analyzed by FACS and WB-based assays, after exposure to SI113, with or without oxidative stress and ionizing radiations. Moreover, autophagy and related reticulum stress response were evaluated. We show here, that i) SGK1 is over-expressed in highly malignant gliomas and that the treatment with SI113 leads to ii) significant increase in caspase-mediated apoptotic cell death in GBM cell lines but not in normal fibroblasts; iii)enhancement of the effects of ionizing radiations; iv) modulation of the response to oxidative reticulum stress; v) induction of cytotoxic autophagy. Evidence reported here underlines the therapeutic potential of SI113 in GBM, suggesting a new therapeutic strategy either alone or in combination with radiotherapy.

Phagocytosis of Apoptotic Trophoblast Cells by Human Endometrial Endothelial Cells Induces Proinflammatory Cytokine Production

PubMed Central

Peng, Bing; Koga, Kaori; Cardenas, Ingrid; Aldo, Paulomi; Mor, Gil

2011-01-01

Problem Apoptosis is a normal constituent of trophoblast turnover in the placenta; however in some cases, this process is related to pregnancy complications such as preeclampsia. Recognition and engulfment of these apoptotic trophoblast cells is important for clearance of dying cells. The aim of this study was to show the cross talk between human endometrial endothelial cells (HEECs) and apoptotic trophoblast cells in an in vitro coculture model and its effect on cytokine production by HEECs. Method of study Fluorescent-labeled HEECs were cocultured with fluorescent-labeled apoptotic human trophoblast cells. Confocal microscopy and flowcytometry were used to show the interaction between these two types of cells. Cytokine profiles were determined using multiplex analysis. Results HEECs are capable to phagocytose apoptotic trophoblasts. This activity is inhibited by the phagocytosis inhibitor cytochalasin B. Phagocytosis of apoptotic trophoblast cells induced the secretion of the proinflammatory cytokines interleukin-6 and monocyte chemoattractant protein-1 by HEECs. Conclusion This study provides the first evidence that HEECs have an ability to phagocytose apoptotic trophoblasts. Furthermore, we demonstrated an inflammatory response of HEECs after phagocytosing the apoptotic trophoblast cells. This event may contribute to the inflammatory response in both normal pregnancy and pathologic pregnancy such as preeclampsia. PMID:20219062

Bad phosphorylation as a target of inhibition in oncology.

PubMed

Bui, Ngoc-Linh-Chi; Pandey, Vijay; Zhu, Tao; Ma, Lan; Basappa; Lobie, Peter E

2018-02-28

Bcl-2 agonist of cell death (BAD) is a BH3-only member of the Bcl-2 family which possesses important regulatory function in apoptosis. BAD has also been shown to possess many non-apoptotic functions closely linked to cancer including regulation of glycolysis, autophagy, cell cycle progression and immune system development. Interestingly, BAD can be either pro-apoptotic or pro-survival depending on the phosphorylation state of three specific serine residues (human S75, S99 and S118). Expression of BAD and BAD phosphorylation patterns have been shown to influence tumor initiation and progression and play a predictive role in disease prognosis, drug response and chemosensitivity in various cancers. This review aims to summarize the current evidence on the functional role of BAD phosphorylation in human cancer and evaluate the potential utility of modulating BAD phosphorylation in cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

Apoptotic Signaling in Mouse Odontogenesis

PubMed Central

Svandova, Eva; Tucker, Abigail S.

2012-01-01

Abstract Apoptosis is an important morphogenetic event in embryogenesis as well as during postnatal life. In the last 2 decades, apoptosis in tooth development (odontogenesis) has been investigated with gradually increasing focus on the mechanisms and signaling pathways involved. The molecular machinery responsible for apoptosis exhibits a high degree of conservation but also organ and tissue specific patterns. This review aims to discuss recent knowledge about apoptotic signaling networks during odontogenesis, concentrating on the mouse, which is often used as a model organism for human dentistry. Apoptosis accompanies the entire development of the tooth and corresponding remodeling of the surrounding bony tissue. It is most evident in its role in the elimination of signaling centers within developing teeth, removal of vestigal tooth germs, and in odontoblast and ameloblast organization during tooth mineralization. Dental apoptosis is caspase dependent and proceeds via mitochondrial mediated cell death with possible amplification by Fas-FasL signaling modulated by Bcl-2 family members. PMID:22204278

N-(3-oxo-acyl) homoserine lactone inhibits tumor growth independent of Bcl-2 proteins.

PubMed

Zhao, Guoping; Neely, Aaron M; Schwarzer, Christian; Lu, Huayi; Whitt, Aaron G; Stivers, Nicole S; Burlison, Joseph A; White, Carl; Machen, Terry E; Li, Chi

2016-02-02

Pseudomonas aeruginosa produces N-(3-oxododecanoyl)-homoserine lactone (C12) as a quorum-sensing molecule for bacterial communication. C12 has also been reported to induce apoptosis in various types of tumor cells. However, the detailed molecular mechanism of C12-triggerred tumor cell apoptosis is still unclear. In addition, it is completely unknown whether C12 possesses any potential therapeutic effects in vivo. Our data indicate that, unlike most apoptotic inducers, C12 evokes a novel form of apoptosis in tumor cells through inducing mitochondrial membrane permeabilization independent of both pro- and anti-apoptotic Bcl-2 proteins. Importantly, C12 inhibits tumor growth in animals regardless of either pro- or anti-apoptotic Bcl-2 proteins. Furthermore, opposite to conventional chemotherapeutics, C12 requires paraoxonase 2 (PON2) to exert its cytotoxicity on tumor cells in vitro and its inhibitory effects on tumor growth in vivo. Overall, our results demonstrate that C12 inhibits tumor growth independent of both pro- and anti-apoptotic Bcl-2 proteins, and through inducing unique apoptotic signaling mediated by PON2 in tumor cells.

N-(3-oxo-acyl) homoserine lactone inhibits tumor growth independent of Bcl-2 proteins

PubMed Central

Zhao, Guoping; Neely, Aaron M.; Schwarzer, Christian; Lu, Huayi; Whitt, Aaron G.; Stivers, Nicole S.; Burlison, Joseph A.; White, Carl; Machen, Terry E.; Li, Chi

2016-01-01

Pseudomonas aeruginosa produces N-(3-oxododecanoyl)-homoserine lactone (C12) as a quorum-sensing molecule for bacterial communication. C12 has also been reported to induce apoptosis in various types of tumor cells. However, the detailed molecular mechanism of C12-triggerred tumor cell apoptosis is still unclear. In addition, it is completely unknown whether C12 possesses any potential therapeutic effects in vivo. Our data indicate that, unlike most apoptotic inducers, C12 evokes a novel form of apoptosis in tumor cells through inducing mitochondrial membrane permeabilization independent of both pro- and anti-apoptotic Bcl-2 proteins. Importantly, C12 inhibits tumor growth in animals regardless of either pro- or anti-apoptotic Bcl-2 proteins. Furthermore, opposite to conventional chemotherapeutics, C12 requires paraoxonase 2 (PON2) to exert its cytotoxicity on tumor cells in vitro and its inhibitory effects on tumor growth in vivo. Overall, our results demonstrate that C12 inhibits tumor growth independent of both pro- and anti-apoptotic Bcl-2 proteins, and through inducing unique apoptotic signaling mediated by PON2 in tumor cells. PMID:26758417

Cooperative binding of Annexin A5 to phosphatidylserine on apoptotic cell membranes

NASA Astrophysics Data System (ADS)

Janko, Christina; Jeremic, Ivica; Biermann, Mona; Chaurio, Ricardo; Schorn, Christine; Muñoz, Luis E.; Herrmann, Martin

2013-12-01

Healthy cells exhibit an asymmetric plasma membrane with phosphatidylserine (PS) located on the cytoplasmic leaflet of the plasma membrane bilayer. Annexin A5-FITC, a PS binding protein, is commonly used to evaluate apoptosis in flow cytometry. PS exposed by apoptotic cells serves as a major ‘eat-me’ signal for phagocytes. Although exposition of PS has been observed after alternative stimuli, no clearance of viable, PS exposing cells has been detected. Thus, besides PS exposure, membranes of viable and apoptotic cells might exhibit specific characteristics. Here, we show that Annexin A5 binds in a cooperative manner to different types of dead cells. Shrunken apoptotic cells thereby showed the highest Hill coefficient values. Contrarily, parafomaldehyde fixation of apoptotic cells completely abrogates the cooperativity effect seen with dead and dying cells. We tend to speculate that the cooperative binding of Annexin A5 to the membranes of apoptotic cells reflects higher fluidity of the exposed membranes facilitating PS clustering.

YiQiFuMai Powder Injection Attenuates Ischemia/Reperfusion-Induced Myocardial Apoptosis Through AMPK Activation.

PubMed

Li, Fang; Zheng, Xianjie; Fan, Xiaoxue; Zhai, Kefeng; Tan, Yisha; Kou, Junping; Yu, Boyang

2016-12-01

The YiQiFuMai powder injection (YQFM), a traditional Chinese medicine (TCM) prescription re-developed based on the well-known TCM formula Sheng-maisan, showed a wide range of pharmacological activities in cardiovascular diseases in clinics. However, its role in protection against myocardial ischemia/reperfusion (MI/R) injury has not been elucidated. The present study not only evaluated the cardioprotective effect of YQFM from MI/R injury but also investigated the potential molecular mechanisms both in vivo and in vitro. The myocardium infarct size, production of lactate dehydrogenase (LDH), creatine kinase (CK), cardiac function, TUNEL staining, and caspase-3 activity were measured. Cell viability was determined, and cell apoptosis was measured by Hoechst 33342 staining and flow cytometry. Mitochondrial membrane potential (ΔΨm) was measured, and ATP content was quantified by bioluminescent assay. Expression of apoptosis-related proteins, including Caspase-3, Bcl-2, Bax, AMPKα, and phospho-AMPKα, was analyzed by western blotting. AMPKα siRNA transfection was also applied to the mechanism elucidation. YQFM at a concentration of 1.06 g/kg significantly reduced myocardium infarct size and the production of LDH, CK in serum, improved the cardiac function, and also produced a significant decrease of apoptotic index. Further, combined treatment with compound C partly attenuated the anti-apoptotic effect of YQFM. In addition, pretreatment with YQFM ranging from 25 to 400 μg/mL markedly improved cell viability and decreased LDH release. Moreover, YQFM inhibited H9c2 apoptosis, blocked the expression of caspase-3, and modulated Bcl-2 and Bax proteins, leading to an increased mitochondrial membrane potential and cellular ATP content. Mechanistically, YQFM activated AMP-activated protein kinase (AMPK) signaling pathways whereas pretreatment with AMPK inhibitor Compound C and application of transfection with AMPKα siRNA attenuated the anti-apoptotic effect of YQFM. Our results indicated that YQFM could provide significant cardioprotection against MI/R injury, and potential mechanisms might suppress cardiomyocytes apoptosis, at least in part, through activating the AMPK signaling pathways.

Sesamol induced apoptotic effect in lung adenocarcinoma cells through both intrinsic and extrinsic pathways.

PubMed

Siriwarin, Boondaree; Weerapreeyakul, Natthida

2016-07-25

Sesamol is a phenolic lignan found in sesame seeds (Sesamum indicum L.) and sesame oil. The anticancer effects and molecular mechanisms underlying its apoptosis-inducing effect were investigated in human lung adenocarcinoma (SK-LU-1) cells. Sesamol inhibited SK-LU-1 cell growth with an IC50 value of 2.7 mM and exhibited less toxicity toward normal Vero cells after 48 h of treatment (Selective index = 3). Apoptotic bodies-the hallmark of apoptosis-were observed in sesamol-treated SK-LU-1 cells, stained with DAPI. Sesamol increased the activity of caspase 8, 9, and 3/7, indicating that apoptotic cell death occurred through both extrinsic and intrinsic pathways. Sesamol caused the loss of mitochondrial transmembrane potential signifying intrinsic apoptosis induction. Decreasing Bid expression revealed crosstalk between the intrinsic and extrinsic apoptotic pathways; demonstrating clearly that sesamol induces apoptosis through both pathways in human lung adenocarcinoma (SK-LU-1) cells. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effect of PDT-treated apoptotic cells on macrophages

NASA Astrophysics Data System (ADS)

Song, Sheng; Xing, Da; Zhou, Fei-fan; Chen, Wei R.

2009-02-01

Recently, the long-term immunological effects of photodynamic therapy have attracted much attention. PDT induced immune response was mainly initiated through necrotic cells and apoptotic cells, as well as immune cells such as macrophages. Nitric oxide (NO) as an important regulatory factor in signal transfer between cells has been wildly studied for generation, development, and metastasis of tumors. NO synthase is a key enzyme in nitric oxide synthesis. However, inducible nitric oxide synthase (iNOS) is usually activated under pathological conditions, such as stress and cancer, which can produce high levels of nitric oxide and contribute to tumor cytotoxicity. In addition, increased NO production by iNOS has been associated with the host immune response and cell apoptosis, which play an important role in many carcinogenesis and anti-carcinoma mechanisms. This study focuses on the NO production in macrophages, induced by mouse breast carcinoma apoptotic cells treated by PDT in vitro, and on the effects of immune response induced by apoptotic cells in tumor cells growth.

ARP2, a novel pro-apoptotic protein expressed in epithelial prostate cancer LNCaP cells and epithelial ovary CHO transformed cells.

PubMed

Mas-Oliva, Jaime; Navarro-Vidal, Enrique; Tapia-Vieyra, Juana Virginia

2014-01-01

Neoplastic epithelial cells generate the most aggressive types of cancers such as those located in the lung, breast, colon, prostate and ovary. During advanced stages of prostate cancer, epithelial cells are associated to the appearance of androgen-independent tumors, an apoptotic-resistant phenotype that ultimately overgrows and promotes metastatic events. We have previously identified and electrophysiologically characterized a novel Ca(2+)-permeable channel activated during apoptosis in the androgen-independent prostate epithelial cancer cell line, LNCaP. In addition, we reported for the first time the cloning and characterization of this channel-like molecule named apoptosis regulated protein 2 (ARP2) associated to a lethal influx of Ca(2+) in Xenopus oocytes. In the present study, LNCaP cells and Chinese hamster ovary cells (CHO cell line) transfected with arp2-cDNA are induced to undergo apoptosis showing an important impact on cell viability and activation of caspases 3 and 7 when compared to serum deprived grown cells and ionomycin treated cells. The subcellular localization of ARP2 in CHO cells undergoing apoptosis was studied using confocal microscopy. While apoptosis progresses, ARP2 initially localized in the peri-nuclear region of cells migrates with time towards the plasma membrane region. Based on the present results and those of our previous studies, the fact that ARP2 constitutes a novel cation channel is supported. Therefore, ARP2 becomes a valuable target to modulate the influx and concentration of calcium in the cytoplasm of epithelial cancer cells showing an apoptotic-resistant phenotype during the onset of an apoptotic event.

Novel association of the obesity risk-allele near Fas Apoptotic Inhibitory molecule 2 (FAIM2) gene with heart rate and study of its effects on myocardial infarction in diabetic participants of the PREDIMED trial

USDA-ARS?s Scientific Manuscript database

The Fas apoptotic pathway has been implicated in type 2 diabetes and cardiovascular disease. Although a polymorphism (rs7138803; G'>'A) near the Fas apoptotic inhibitory molecule 2 (FAIM2) locus has been related to obesity, its association with other cardiovascular risk factors and disease remains u...

Combination of nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy as a novel therapeutic application to manage the pain and treat many clinical conditions

NASA Astrophysics Data System (ADS)

Halasa, Salaheldin; Dickinson, Eva

2014-02-01

From hypertension to diabetes, cancer to HIV, stroke to memory loss and learning disorders to septic shock, male impotence to tuberculosis, there is probably no pathological condition where nitric oxide does not play an important role. Nitric oxide is an analgesic, immune-modulator, vasodilator, anti-apoptotic, growth modulator, angiogenetic, anti-thrombotic, anti-inflammatory and neuro-modulator. Because of the above actions of nitric oxide, many clinical conditions associated with abnormal Nitric oxide (NO) production and bioavailability. Our novel therapeutic approach is to restore the homeostasis of nitric oxide and replace the lost cells by combining nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy.

Heme oxygenase/carbon monoxide signaling pathways: regulation and functional significance.

PubMed

Ryter, Stefan W; Otterbein, Leo E; Morse, Danielle; Choi, Augustine M K

2002-01-01

Carbon monoxide (CO), a gaseous second messenger, arises in biological systems during the oxidative catabolism of heme by the heme oxygenase (HO) enzymes. HO exists as constitutive (HO-2, HO-3) and inducible isoforms (HO-1), the latter which responds to regulation by multiple stress-stimuli. HO-1 confers protection in vitro and in vivo against oxidative cellular stress. Although the redox active compounds that are generated from HO activity (i.e. iron, biliverdin-IXalpha, and bilirubin-IXa) potentially modulate oxidative stress resistance, increasing evidence points to cytoprotective roles for CO. Though not reactive, CO regulates vascular processes such as vessel tone, smooth muscle proliferation, and platelet aggregation, and possibly functions as a neurotransmitter. The latter effects of CO depend on the activation of guanylate cyclase activity by direct binding to the heme moiety of the enzyme, stimulating the production of cyclic 3':5'-guanosine monophosphate. CO potentially interacts with other intracellular hemoprotein targets, though little is known about the functional significance of such interactions. Recent progress indicates that CO exerts novel anti-inflammatory and anti-apoptotic effects dependent on the modulation of the p38 mitogen activated protein kinase (MAPK)-signaling pathway. By virtue of these effects, CO confers protection in oxidative lung injury models, and likely plays a role in HO-1 mediated tissue protection.

Effects of different extracts of curcumin on TPC1 papillary thyroid cancer cell line.

PubMed

Perna, Angelica; De Luca, Antonio; Adelfi, Laura; Pasquale, Tammaro; Varriale, Bruno; Esposito, Teresa

2018-02-15

The thyroid gland is one of the largest endocrine glands in the body. The vast majority of TCs (> 90%) originate from follicular cells and are defined as differentiated thyroid cancers (DTC) and the two histological subtypes are the papillary TC with its variants and the follicular TC. Curcumin possesses a wide variety of biological functions, and thanks to its properties, it has gained considerable attention due to its profound medicinal values (Prasad, Gupta, Tyagi, and Aggarwal, Biotechnol Adv 32:1053-1064, 2014). We have undertaken the present work in order to define the possible role of curcumin in modulating the genetic expression of cell markers and to understand the effectiveness of this nutraceutical in modulating the regression of cancer phenotype. As a template we used the TPC-1 cells treated with the different extracts of turmeric, and examined the levels of expression of different markers (proliferative, inflammatory, antioxidant, apoptotic). Treatment with the three different curcumin extracts displays anti-inflammatory, antioxidant properties and it is able to influence cell cycle with slightly different effects upon the extracts. Furthermore curcumin is able to influence cell metabolic activity vitality. In conclusion curcumin has the potential to be developed as a safe therapeutic but further studies are needed to verify its antitumor ability in vivo.

The apoptotic effect of simvastatin via the upregulation of BIM in nonsmall cell lung cancer cells.

PubMed

Lee, Hwa Young; Kim, In Kyoung; Lee, Hye In; Mo, Jin Young; Yeo, Chang Dong; Kang, Hyeon Hui; Moon, Hwa Sik; Lee, Sang Haak

2016-01-01

Statins are known to have pleiotropic effects that induce cell death in certain cancer cells. BIM is a member of the bcl-2 gene family, which promotes apoptotic cell death. This study investigated the hypothesis that simvastatin has pro-apoptotic effects in epidermal growth factor receptor (EGFR)-mutated lung cancer cell lines via the upregulation of the expression of the BIM protein. The cytotoxic effects of simvastatin on gefitinib-sensitive (HCC827, E716-A750del) and -resistant (H1975, T790M + L858R) nonsmall cell lung cancer (NSCLC) cells were compared. Cell proliferation and expression of apoptosis-related and EGFR downstream signaling proteins were evaluated. Expression of BIM was compared in H1975 cells after treatment with simvastatin or gefitinib. SiRNA-mediated BIM depletion was performed to confirm whether the cytotoxicity of simvastatin was mediated by the expression of BIM. H1975 cells showed significantly reduced viability compared with HCC827 cells after treatment with simvastatin (2 μM) for 48 hours. In simvastatin-treated H1975 cells, expression of pro-apoptotic proteins was increased and the phosphorylation of ERK 1/2 (p-ERK 1/2) was reduced. Expression of BIM was suppressed by gefitinib (1 μM) treatment in H1975 cells, but it was significantly increased by treatment with simvastatin. BIM depletion by siRNA transfection enhanced the viability of H1975 cells that received simvastatin treatment and increased their expression of anti-apoptotic proteins. Simvastatin restored the expression of BIM to induce apoptotic cell death in NSCLC cells harboring an EGFR-resistant mutation. Our study suggests the potential utility of simvastatin as a BIM-targeted treatment for NSCLC.

Effect of Temporal Pattern of Radiation in Intensity Modulated Radiotherapy on Cell Cycle Progression and Apoptosis of ACHN Renal Cell Carcinoma Cell Line.

PubMed

Khorramizadeh, Maryam; Saberi, Alihossein; Tahmasebi-Birgani, Mohammadjavad; Shokrani, Parvaneh; Amouhedari, Alireza

The existence of a hypersensitive radiation response to doses below 1 Gy is well established for many normal and tumor cell lines. The aim of this study was to ascertain the impact of temporal pattern modeling IMRT on survival, cell cycle and apoptosis of human RCC cell line ACHN, so as to provide radiobiological basis for optimizing IMRT plans for this disease. The ACHN renal cell carcinoma cell line was used in this study. Impact of the triangle, V, small-large or large-small temporal patterns in the presence and absence of threshold dose of hyper-radiosensitivity at the beginning of patterns were studied using soft agarclonogenic assays. Cell cycle and apoptosis analysis were performed after irradiation with the temporal patterns. For triangle and small-large dose sequences, survival fraction was significantly reduced after irradiation with or without threshold dose of hyper-radiosensitivity at the beginning of the patterns. In all of the dose patterns, cell cycle distributions and the percentage of apoptotic cells at 24 h after irradiation with or without priming dose of hyper-radiosensitivity showed no significant difference. However, apoptotic cells were increased when beams with the smallest dose applied at the beginning of dose pattern like triangle and small-large dose sequence. These data show that the biologic effects of single fraction may differ in clinical settings depending on the size and sequence of the partial fractions. Doses at the beginning but not at the end of sequences may change cytotoxicity effects of radiation.

Sulforaphane inhibits growth of human breast cancer cells and augments the therapeutic index of the chemotherapeutic drug, gemcitabine.

PubMed

Hussain, Arif; Mohsin, Javeria; Prabhu, Sathyen Alwin; Begum, Salema; Nusri, Qurrat El-Ain; Harish, Geetganga; Javed, Elham; Khan, Munawwar Ali; Sharma, Chhavi

2013-01-01

Phytochemicals are among the natural chemopreventive agents with most potential for delaying, blocking or reversing the initiation and promotional events of carcinogenesis. They therefore offer cancer treatment strategies to reduce cancer related death. One such promising chemopreventive agent which has attracted considerable attention is sulforaphane (SFN), which exhibits anti-cancer, anti-diabetic, and anti-microbial properties. The present study was undertaken to assess effect of SFN alone and in combination with a chemotherapeutic agent, gemcitabine, on the proliferative potential of MCF-7 cells by cell viability assay and authenticated the results by nuclear morphological examination. Further we analyzed the modulation of expression of Bcl-2 and COX-2 on treatment of these cells with SFN by RT-PCR. SFN showed cytotoxic effects on MCF-7 cells in a dose- and time-dependent manner via an apoptotic mode of cell death. In addition, a combinational treatment of SFN and gemcitabine on MCF-7 cells resulted in growth inhibition in a synergistic manner with a combination index (CI) <1. Notably, SFN was found to significantly downregulate the expression of Bcl-2, an anti-apoptotic gene, and COX-2, a gene involved in inflammation, in a time-dependent manner. These results indicate that SFN induces apoptosis and anti-inflammatory effects on MCF-7 cells via downregulation of Bcl-2 and COX-2 respectively. The combination of SFN and gemcitabine may potentiate the efficacy of gemcitabine and minimize the toxicity to normal cells. Taken together, SFN may be a potent anti-cancer agent for breast cancer treatment.

Ameliorative Effect of Fisetin on Cisplatin-Induced Nephrotoxicity in Rats via Modulation of NF-κB Activation and Antioxidant Defence

PubMed Central

Sahu, Bidya Dhar; Kalvala, Anil Kumar; Koneru, Meghana; Mahesh Kumar, Jerald; Kuncha, Madhusudana; Rachamalla, Shyam Sunder; Sistla, Ramakrishna

2014-01-01

Nephrotoxicity is a dose-dependent side effect of cisplatin limiting its clinical usage in the field of cancer chemotherapy. Fisetin is a bioactive flavonoid with recognized antioxidant and anti-inflammatory properties. In the present study, we investigated the potential renoprotective effect and underlying mechanism of fisetin using rat model of cisplatin-induced nephrotoxicity. The elevation in serum biomarkers of renal damage (blood urea nitrogen and creatinine); degree of histopathological alterations and oxidative stress were significantly restored towards normal in fisetin treated, cisplatin challenged animals. Fisetin treatment also significantly attenuated the cisplatin-induced IκBα degradation and phosphorylation and blocked the NF-κB (p65) nuclear translocation, with subsequent elevation of pro-inflammatory cytokine, TNF-α, protein expression of iNOS and myeloperoxidase activities. Furthermore, fisetin markedly attenuated the translocation of cytochrome c protein from the mitochondria to the cytosol; decreased the expression of pro-apoptotic proteins including Bax, cleaved caspase-3, cleaved caspase-9 and p53; and prevented the decline of anti-apoptotic protein, Bcl-2. The cisplatin-induced mRNA expression of NOX2/gp91phox and NOX4/RENOX and the NADPH oxidase enzyme activity were also significantly lowered by fisetin treatment. Moreover, the evaluated mitochondrial respiratory enzyme activities and mitochondrial antioxidants were restored by fisetin treatment. Estimation of platinum concentration in kidney tissues revealed that fisetin treatment along with cisplatin did not alter the cisplatin uptake in kidney tissues. In conclusion, these findings suggest that fisetin may be used as a promising adjunct candidate for cisplatin use. PMID:25184746

A synthetic cryptochrome inhibitor induces anti-proliferative effects and increases chemosensitivity in human breast cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chun, Sung Kook; Department of Biological Sciences, Seoul National University, Seoul, 151-747; Department of Brain & Cognitive Sciences, Seoul National University, Seoul, 151-747

Disruption of circadian rhythm is a major cause of breast cancer in humans. Cryptochrome (CRY), a circadian transcription factor, is a risk factor for initiation of breast cancer, and it is differentially expressed between normal and breast cancer tissues. Here, we evaluated the anti-proliferative and pro-apoptotic activity of KS15, a recently discovered small-molecule inhibitor of CRY, in human breast cancer cells. First, we investigated whether KS15 treatment could promote E-box-mediated transcription by inhibiting the activity of CRY in MCF-7 human breast cancer cells. Protein and mRNA levels of regulators of cell cycle and apoptosis, as well as core clock genes,more » were differentially modulated in response to KS15. Next, we investigated whether KS15 could inhibit proliferation and increase sensitivity to anti-tumor drugs in MCF-7 cells. We found that KS15 decreased the speed of cell growth and increased the chemosensitivity of MCF-7 cells to doxorubicin and tamoxifen, but had no effect on MCF-10A cells. These findings suggested that pharmacological inhibition of CRY by KS15 exerts an anti-proliferative effect and increases sensitivity to anti-tumor drugs in a specific type of breast cancer. - Highlights: • Cryptochrome inhibitor (KS15) has anti-tumor activity to human breast cancer cells. • KS15 induces differential changes in cell cycle regulators and pro-apoptotic genes. • KS15 inhibits MCF-7 cell growth and enhances susceptibility to anti-tumor drugs.« less

Momordica charantia polysaccharides could protect against cerebral ischemia/reperfusion injury through inhibiting oxidative stress mediated c-Jun N-terminal kinase 3 signaling pathway.

PubMed

Gong, Juanjuan; Sun, Fumou; Li, Yihang; Zhou, Xiaoling; Duan, Zhenzhen; Duan, Fugang; Zhao, Lei; Chen, Hansen; Qi, Suhua; Shen, Jiangang

2015-04-01

Momordica charantia (MC) is a medicinal plant for stroke treatment in Traditional Chinese Medicine, but its active compounds and molecular targets are unknown yet. M. charantia polysaccharide (MCP) is one of the important bioactive components in MC. In the present study, we tested the hypothesis that MCP has neuroprotective effects against cerebral ischemia/reperfusion injury through scavenging superoxide (O2(-)), nitric oxide (NO) and peroxynitrite (ONOO(-)) and inhibiting c-Jun N-terminal protein kinase (JNK3) signaling cascades. We conducted experiments with in vivo global and focal cerebral ischemia/reperfusion rat models and in vitro oxygen glucose deprivation (OGD) neural cells. The effects of MCP on apoptotic cell death and infarction volume, the bioactivities of scavenging O2(-), NO and ONOO(-), inhibiting lipid peroxidation and modulating JNK3 signaling pathway were investigated. Major results are summarized as below: (1) MCP dose-dependently attenuated apoptotic cell death in neural cells under OGD condition in vitro and reduced infarction volume in ischemic brains in vivo; (2) MCP had directing scavenging effects on NO, O2(-) and ONOO(-) and inhibited lipid peroxidation; (3) MCP inhibited the activations of JNK3/c-Jun/Fas-L and JNK3/cytochrome C/caspases-3 signaling cascades in ischemic brains in vivo. Taken together, we conclude that MCP could be a promising neuroprotective ingredient of M. charantia and its mechanisms could be at least in part attributed to its antioxidant activities and inhibiting JNK3 signaling cascades during cerebral ischemia/reperfusion injury. Copyright © 2014 Elsevier Ltd. All rights reserved.

Kidney stone matrix proteins ameliorate calcium oxalate monohydrate induced apoptotic injury to renal epithelial cells.

PubMed

Narula, Shifa; Tandon, Simran; Singh, Shrawan Kumar; Tandon, Chanderdeep

2016-11-01

Kidney stone formation is a highly prevalent disease, affecting 8-10% of the human population worldwide. Proteins are the major constituents of human kidney stone's organic matrix and considered to play critical role in the pathogenesis of disease but their mechanism of modulation still needs to be explicated. Therefore, in this study we investigated the effect of human kidney stone matrix proteins on the calcium oxalate monohydrate (COM) mediated cellular injury. The renal epithelial cells (MDCK) were exposed to 200μg/ml COM crystals to induce injury. The effect of proteins isolated from human kidney stone was studied on COM injured cells. The alterations in cell-crystal interactions were examined by phase contrast, polarizing, fluorescence and scanning electron microscopy. Moreover, its effect on the extent of COM induced cell injury, was quantified by flow cytometric analysis. Our study indicated the antilithiatic potential of human kidney stone proteins on COM injured MDCK cells. Flow cytometric analysis and fluorescence imaging ascertained that matrix proteins decreased the extent of apoptotic injury caused by COM crystals on MDCK cells. Moreover, the electron microscopic studies of MDCK cells revealed that matrix proteins caused significant dissolution of COM crystals, indicating cytoprotection against the impact of calcium oxalate injury. The present study gives insights into the mechanism implied by urinary proteins to restrain the pathogenesis of kidney stone disease. This will provide a better understanding of the formation of kidney stones which can be useful for the proper management of the disease. Copyright © 2016 Elsevier Inc. All rights reserved.

Expression Changes of Apoptotic Genes in Tissues from Mice Exposed to Nicotine

PubMed Central

Jalili, Cyrus; Salahshoor, Mohammad Reza; Moradi, Mohammad Taher; Ahookhash, Maryam; Taghadosi, Mehdi; Sohrabi, Maryam

2017-01-01

Objective: Smoking is the leading preventable cause of various diseases such as lung cancer, chronic obstructive pulmonary disease and cardiovascular disease. Nicotine, one of the major toxic components of tobacco, contributes to the pathogenesis of different diseases. Methods: Given the controversy about nicotine toxicity, the present study was conducted to determine apoptotic effects of nicotine on the heart, kidney, lung and liver of male mice. Real-time PCR was performed to identify mRNA expression changes in apoptotic-related genes between nicotine treated and control mice. Result: In the heart and lung, nicotine caused significant decrease in P53, Bax and Caspase-3 mRNA expression levels compared to the control group. However, in the kidney and liver, the result was significant increase in Bax, Caspase-2, Caspase-3 and a significant decrease in P53 mRNA expression (p<0.01). DNA fragmentation assays indicated no fragmentation in the heart and lung, but in the kidney and liver of nicotine treated mice, isolated DNA was fragmented. Conclusion: Our study provided insight into the molecular mechanisms of nicotine anti-apoptotic effects on the heart and lung as well as pro-apoptotic effects on kidney and liver via a P53-independent pathway. PMID:28240526

Neuroprotection by Caffeine in Hyperoxia-Induced Neonatal Brain Injury

PubMed Central

Endesfelder, Stefanie; Weichelt, Ulrike; Strauß, Evelyn; Schlör, Anja; Sifringer, Marco; Scheuer, Till; Bührer, Christoph; Schmitz, Thomas

2017-01-01

Sequelae of prematurity triggered by oxidative stress and free radical-mediated tissue damage have coined the term “oxygen radical disease of prematurity”. Caffeine, a potent free radical scavenger and adenosine receptor antagonist, reduces rates of brain damage in preterm infants. In the present study, we investigated the effects of caffeine on oxidative stress markers, anti-oxidative response, inflammation, redox-sensitive transcription factors, apoptosis, and extracellular matrix following the induction of hyperoxia in neonatal rats. The brain of a rat pups at postnatal Day 6 (P6) corresponds to that of a human fetal brain at 28–32 weeks gestation and the neonatal rat is an ideal model in which to investigate effects of oxidative stress and neuroprotection of caffeine on the developing brain. Six-day-old Wistar rats were pre-treated with caffeine and exposed to 80% oxygen for 24 and 48 h. Caffeine reduced oxidative stress marker (heme oxygenase-1, lipid peroxidation, hydrogen peroxide, and glutamate-cysteine ligase catalytic subunit (GCLC)), promoted anti-oxidative response (superoxide dismutase, peroxiredoxin 1, and sulfiredoxin 1), down-regulated pro-inflammatory cytokines, modulated redox-sensitive transcription factor expression (Nrf2/Keap1, and NFκB), reduced pro-apoptotic effectors (poly (ADP-ribose) polymerase-1 (PARP-1), apoptosis inducing factor (AIF), and caspase-3), and diminished extracellular matrix degeneration (matrix metalloproteinases (MMP) 2, and inhibitor of metalloproteinase (TIMP) 1/2). Our study affirms that caffeine is a pleiotropic neuroprotective drug in the developing brain due to its anti-oxidant, anti-inflammatory, and anti-apoptotic properties. PMID:28106777

Apoptosis of leukemia K562 and Molt-4 cells induced by emamectin benzoate involving mitochondrial membrane potential loss and intracellular Ca2+ modulation.

PubMed

Yun, Xinming; Rao, Wenbing; Xiao, Ciying; Huang, Qingchun

2017-06-01

Leukemia threatens millions of people's health and lives, and the pesticide-induced leukemia has been increasingly concerned because of the etiologic exposure. In this paper, cytotoxic effect of emamectin benzoate (EMB), an excellent natural-product insecticide, was evaluated through monitoring cell viability, cell apoptosis, mitochondrial membrane potential and intracellular Ca 2+ concentration ([Ca 2+ ] i ) in leukemia K562 and Molt-4 cells. Following the exposure to EMB, cell viability was decreased and positive apoptosis of K562 and Molt-4 cells was increased in a concentration- and time- dependent fashion. In the treatment of 10μM EMB, apoptotic cells accounted for 93.0% to K562 cells and 98.9% to Molt-4 cells based on the control, meanwhile, 63.47% of K562 cells and 81.15% of Molt-4 cells exhibited late apoptotic and necrotic features with damaged cytoplasmic membrane. 48h exposure to 10μM EMB increased significantly the great number of cells with mitochondrial membrane potential (MMP) loss, and the elevation of [Ca 2+ ] i level was peaked and persisted within 70s in K562 cells whilst 50s in Molt-4 cells. Moreover, a stronger cytotoxicity of EMB was further observed than that of imatinib. The results authenticate the efficacious effect of EMB as a potential anti-leukemia agent and an inconsistency with regard to insecticide-induced leukemia. Copyright © 2017 Elsevier B.V. All rights reserved.

Neuroprotection by Caffeine in Hyperoxia-Induced Neonatal Brain Injury.

PubMed

Endesfelder, Stefanie; Weichelt, Ulrike; Strauß, Evelyn; Schlör, Anja; Sifringer, Marco; Scheuer, Till; Bührer, Christoph; Schmitz, Thomas

2017-01-18

Sequelae of prematurity triggered by oxidative stress and free radical-mediated tissue damage have coined the term "oxygen radical disease of prematurity". Caffeine, a potent free radical scavenger and adenosine receptor antagonist, reduces rates of brain damage in preterm infants. In the present study, we investigated the effects of caffeine on oxidative stress markers, anti-oxidative response, inflammation, redox-sensitive transcription factors, apoptosis, and extracellular matrix following the induction of hyperoxia in neonatal rats. The brain of a rat pups at postnatal Day 6 (P6) corresponds to that of a human fetal brain at 28-32 weeks gestation and the neonatal rat is an ideal model in which to investigate effects of oxidative stress and neuroprotection of caffeine on the developing brain. Six-day-old Wistar rats were pre-treated with caffeine and exposed to 80% oxygen for 24 and 48 h. Caffeine reduced oxidative stress marker (heme oxygenase-1, lipid peroxidation, hydrogen peroxide, and glutamate-cysteine ligase catalytic subunit (GCLC)), promoted anti-oxidative response (superoxide dismutase, peroxiredoxin 1, and sulfiredoxin 1), down-regulated pro-inflammatory cytokines, modulated redox-sensitive transcription factor expression (Nrf2/Keap1, and NFκB), reduced pro-apoptotic effectors (poly (ADP-ribose) polymerase-1 (PARP-1), apoptosis inducing factor (AIF), and caspase-3), and diminished extracellular matrix degeneration (matrix metalloproteinases (MMP) 2, and inhibitor of metalloproteinase (TIMP) 1/2). Our study affirms that caffeine is a pleiotropic neuroprotective drug in the developing brain due to its anti-oxidant, anti-inflammatory, and anti-apoptotic properties.

Contrasting apoptotic responses of conjugated linoleic acid in the liver of obese Zucker rats fed palm oil or ovine fat.

PubMed

Lopes, Paula A; Martins, Susana V; Viana, Ricardo S J; Ramalho, Rita M; Alfaia, Cristina M; Pinho, Mário S; Jerónimo, Eliana; Bessa, Rui J B; Castro, Matilde F; Rodrigues, Cecília M P; Prates, José A M

2011-08-01

We hypothesized that reducing weight properties of conjugated linoleic acid (CLA) are due to adipocyte apoptosis and that CLA differentially modulates the apoptotic responses in hepatic lipotoxicity from rats fed saturated fat diets. Obese Zucker rats were fed atherogenic diets (2%w/w of cholesterol) formulated with high (15%w/w) saturated fat, from vegetable or animal origin, supplemented or not with 1% of a mixture (1:1) of cis-9, trans-11 and trans-10, cis-12 CLA isomers for 14 weeks. CLA induced no changes on retroperitoneal fat depot weight, which was in line with similar levels of apoptosis. Interestingly, CLA had a contrasting effect on cell death in the liver according to the dietary fat. CLA increased hepatocyte apoptosis, associated with upregulation of Fas protein in rats fed palm oil, compared to rats receiving palm oil alone. However, rats fed ovine fat alone displayed the highest levels of hepatic cell death, which were decreased in rats fed ovine fat plus CLA. This reducing effect of CLA was related to positively restoring endoplasmic reticulum (ER) ATF-6α, BiP and CHOP protein levels and increasing phosphorylated c-Jun NH(2)-terminal kinase (JNK) and c-Jun, thus suggesting an adaptive response of cell survival. These findings reinforce the role of CLA as regulator of apoptosis in the liver. Moreover, the dietary fat composition is a key factor in activation of apoptosis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Efficacy of PLGA-loaded apigenin nanoparticles in Benzo[a]pyrene and ultraviolet-B induced skin cancer of mice: mitochondria mediated apoptotic signalling cascades.

PubMed

Das, Sreemanti; Das, Jayeeta; Samadder, Asmita; Paul, Avijit; Khuda-Bukhsh, Anisur Rahman

2013-12-01

Skin cancer is increasing at an alarming rate and becoming resistant to conventional chemotherapy necessitating improved drug delivery system. We loaded apigenin (Ap), a dietary flavonoid having anti-cancer property, with poly (lactic-co-glycolide) (PLGA) nanoparticles (NAp) to explore if nano-encapsulation could enhance anti-carcinogenic effect against ultra-violet B (UVB) and Benzo(a)pyrene (BaP) induced skin tumor and mitochondrial dysfunction in mice. Particle size, morphology and zeta potential of NAp were determined using dynamic light scattering and atomic force microscopy. Tumor incidence and multiplicity in UVB-BaP induced mice with/without NAp treatment were ascertained and their histolopathological sections and chromosomal aberrations were studied. ROS accumulation and mitochondrial functioning through relevant markers like mitochondrial transmembrane potential were analyzed. Mitochondrial volume changes/swelling, cytochrome c (cyt c) release, mRNA and protein expressions of Apaf-1, bax, bcl-2, cyt c, cleaved caspase-9 and 3 were studied. Results showed that NAp produced better effects than Ap, due to their smaller size, and faster mobility. NAp reduced tissue damage and frequency of chromosomal aberrations, increased ROS accumulation to mediate mitochondrial-apoptosis through modulation of several apoptotic markers and mitochondrial matrix swelling. NAp showed ameliorative potentials in combating skin cancer and therefore has greater prospect of use in therapeutic management of skin cancer. Copyright © 2013 Elsevier Ltd. All rights reserved.

Antiproliferative and apoptosis-induction studies of 5-hydroxy 3',4',7-trimethoxyflavone in human breast cancer cells MCF-7: an in vitro and in silico approach.

PubMed

Sudha, A; Srinivasan, P; Kanimozhi, V; Palanivel, K; Kadalmani, B

2018-05-08

The aim of this study was to find the efficacy of 5-hydroxy 3',4',7-trimethoxyflavone (HTMF), a flavonoid compound isolated from the medicinal plant Lippia nodiflora, in inhibiting the proliferation and inducing apoptosis in human breast cancer cell line MCF-7. The anti-proliferative effect of the compound HTMF was confirmed using MTT cytotoxicity assay. Increased apoptotic induction by HTMF was demonstrated by acridine orange/ethidium bromide (AO/EtBr) and Hoechst 33258 staining studies. The phosphatidylserine translocation, an early feature of apoptosis and DNA damage were revealed through AnnexinV-Cy3 staining and comet assay. Moreover, the significant elevation of cellular ROS was observed in the treated cells, as measured by 2,7-diacetyl dichlorofluorescein (DCFH-DA). The mRNA expression studies also supported the effectiveness of HTMF by shifting the Bax:Bcl-2 ratio. The treatment of MCF-7 cells with HTMF encouraged apoptosis through the modulation of apoptotic markers, such as p53, Bcl-2, Bax, and cleaved PARP. In silico molecular docking and dynamics studies with MDM2-p53 protein revealed that HTMF was more potent compound that could inhibit the binding of MDM2 with p53 and, therefore, could trigger apoptosis in cancer cell. Overall, this study brings up scientific evidence for the efficacy of HTMF against MCF-7 breast cancer cells.

Induction of S phase cell arrest and caspase activation by polysaccharide peptide isolated from Coriolus versicolor enhanced the cell cycle dependent activity and apoptotic cell death of doxorubicin and etoposide, but not cytarabine in HL-60 cells.

PubMed

Hui, Kenrie Pui-Yan; Sit, Wai-Hung; Wan, Jennifer Man-Fan

2005-07-01

Activation of the cell death program (apoptosis) is a strategy for the treatment of human cancer, and unfortunately a large number of drugs identified as cell cycle-specific agents for killing cancer cells are also toxic to normal cells. The present study demonstrates that the polysaccharide peptide (PSP) extracted from the Chinese medicinal mushroom, Coriolus versicolor, used in combination therapy in China, has the ability to lower the cytotoxicity of certain anti-leukemic drugs via their interaction with cell cycle-dependent and apoptotic pathways. Flow cytometry analysis demonstrated that pre-treatment of PSP (25-100 microg/ml) dose-dependently enhanced the cell cycle perturbation and apoptotic activity of doxorubicin (Doxo) and etoposide (VP-16), but not cytarabine (Ara-C) in human promyelocytic leukemia HL-60 cells. The antagonistic result from combined treatment with Ara-C and PSP may be caused by the removal of HL-60 cells in the G1-S boundary by PSP before exposure to Ara-C. A negative correlation between the increase in apoptotic cell population (pre-G1 peak) with the S-phase cell population expression (R2=0.998), the expression of cyclin E expression (R2=0.872) and caspase 3 activity (R2=0.997) suggests that PSP enhanced the apoptotic machinery of Doxo and VP-16 in a cell cycle-dependent manner and is mediated, at least in part, by the PSP-mediated modulation of the regulatory checkpoint cyclin E and caspase 3. This study is the first to describe the cell cycle mechanistic action of PSP and its interaction with other anticancer agents. Our data support the potential development of PSP as an adjuvant for leukemia treatment, but also imply the importance of understanding its interaction with individual anticancer agents.

Apolipoprotein E Is a Ligand for Triggering Receptor Expressed on Myeloid Cells 2 (TREM2)*

PubMed Central

Atagi, Yuka; Liu, Chia-Chen; Painter, Meghan M.; Chen, Xiao-Fen; Verbeeck, Christophe; Zheng, Honghua; Li, Xia; Rademakers, Rosa; Kang, Silvia S.; Xu, Huaxi; Younkin, Steven; Das, Pritam; Fryer, John D.; Bu, Guojun

2015-01-01

Several heterozygous missense mutations in the triggering receptor expressed on myeloid cells 2 (TREM2) have recently been linked to risk for a number of neurological disorders including Alzheimer disease (AD), Parkinson disease, and frontotemporal dementia. These discoveries have re-ignited interest in the role of neuroinflammation in the pathogenesis of neurodegenerative diseases. TREM2 is highly expressed in microglia, the resident immune cells of the central nervous system. Along with its adaptor protein, DAP12, TREM2 regulates inflammatory cytokine release and phagocytosis of apoptotic neurons. Here, we report apolipoprotein E (apoE) as a novel ligand for TREM2. Using a biochemical assay, we demonstrated high-affinity binding of apoE to human TREM2. The functional significance of this binding was highlighted by increased phagocytosis of apoE-bound apoptotic N2a cells by primary microglia in a manner that depends on TREM2 expression. Moreover, when the AD-associated TREM2-R47H mutant was used in biochemical assays, apoE binding was vastly reduced. Our data demonstrate that apoE-TREM2 interaction in microglia plays critical roles in modulating phagocytosis of apoE-bound apoptotic neurons and establish a critical link between two proteins whose genes are strongly linked to the risk for AD. PMID:26374899

Apoptosis-Related Gene Expression in an Adult Cohort with Crimean-Congo Hemorrhagic Fever.

PubMed

Guler, Nil; Eroglu, Cafer; Yilmaz, Hava; Karadag, Adil; Alacam, Hasan; Sunbul, Mustafa; Fletcher, Tom E; Leblebicioglu, Hakan

2016-01-01

Crimean-Congo Hemorrhagic Fever (CCHF) is a life threatening acute viral infection characterized by fever, bleeding, leukopenia and thrombocytopenia. It is a major emerging infectious diseases threat, but its pathogenesis remains poorly understood and few data exist for the role of apoptosis in acute infection. We aimed to assess apoptotic gene expression in leukocytes in a cross-sectional cohort study of adults with CCHF. Twenty participants with CCHF and 10 healthy controls were recruited at a tertiary CCHF unit in Turkey; at admission baseline blood tests were collected and total RNA was isolated. The RealTime ready Human Apoptosis Panel was used for real-time PCR, detecting differences in gene expression. Participants had CCHF severity grading scores (SGS) with low risk score (10 out of 20) and intermediate or high risk scores (10 out of 20) for mortality. Five of 20 participants had a fatal outcome. Gene expression analysis showed modulation of pro-apoptotic and anti-apoptotic genes that facilitate apoptosis in the CCHF patient group. Dominant extrinsic pathway activation, mostly related with TNF family members was observed. Severe and fatal cases suggest additional intrinsic pathway activation. The clinical significance of relative gene expression is not clear, and larger longitudinal studies with simultaneous measurement of host and viral factors are recommended.

Evidence for apoptosis in human atherogenesis and in a rat vascular injury model.

PubMed Central

Han, D. K.; Haudenschild, C. C.; Hong, M. K.; Tinkle, B. T.; Leon, M. B.; Liau, G.

1995-01-01

Apoptosis is a physiological cell death process important for normal development and involved in many pathological conditions. In atherosclerosis, pathological accumulation of cells in the intima has been attributed to the migration and proliferation of smooth muscle cells, macrophages, and lymphocytes. In this report, we explored the possibility that apoptosis may also contribute to the pathogenesis of this disease. We examined 35 human atherosclerotic lesion samples and identified a substantial number of cells undergoing apoptosis in 25 of the samples. Furthermore, in a rat vascular injury model, apoptotic cells were specifically identified in the neointima. The presence of apoptotic cells was demonstrated by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling, nuclear staining with propidium iodide, and electron microscopy. Immunostaining with cell-type-specific markers and subsequent terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling analysis on the same sample revealed that the majority of the apoptotic cells were modulated smooth muscle cells as well as macrophages. These results indicate that apoptosis occurs in cells of the injured blood vessel as well as the advanced atherosclerotic lesion and that physiological cell death may have an important role in determining the course of atherogenesis. Images Figure 1 Figure 2 Figure 4 Figure 5 PMID:7639326

Cardioprotective activity of urocortin by preventing caspase-independent, non-apoptotic death in cultured neonatal rat cardiomyocytes exposed to ischemia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takatani-Nakase, Tomoka, E-mail: nakase@mukogawa-u.ac.jp; Takahashi, Koichi, E-mail: koichi@mukogawa-u.ac.jp

Research highlights: {yields} Ischemia induces high level of iPLA{sub 2} resulting in caspase-independent myocyte death. {yields} Urocortin causes iPLA{sub 2} down-regulation leading to avoidance of non-apoptotic death. {yields} The survival-promoting effect of urocortin is abrogated by CRH receptor antagonist. -- Abstract: Caspase-independent, non-apoptotic cell death in ischemic heart disease is considered to be one of the important therapeutic targets, however, the detailed mechanisms of this cell death process are not clear. In this study, we investigated the mechanisms of non-apoptotic cell death in cultured neonatal rat cardiomyocytes during ischemia, and the cardioprotection by preventing the mechanisms. We found that ischemiamore » caused elevation of the phospholipase A{sub 2} (iPLA{sub 2}) expression in the myocytes, leading to distinctive non-apoptotic nuclear shrinkage, and cell death. Moreover, we investigated whether the potent cardioprotective corticotropin-releasing hormone (CRH), urocortin, which had been less focused on non-apoptotic cell death, inhibits the ischemic myocyte death. Ischemia-augmented nuclear shrinkage of the myocytes was suppressed by the pretreatment of {approx}10 nM urocortin before the cells were exposed to ischemia. Urocortin could significantly suppress the expression and activity of iPLA{sub 2}, resulting in preventing the ischemia-induced cell death. The survival-promoting effect of urocortin was abrogated by the CRH receptor antagonist astressin. These findings provide the first evidence linking the targets of the urocortin-mediated cardioprotection to the suppression of the caspase-independent, non-apoptotic death in cardiac myocytes exposed to ischemia.« less

Hypoxic preconditioning potentiates the trophic effects of mesenchymal stem cells on co-cultured human primary hepatocytes.

PubMed

Qin, Harry H; Filippi, Céline; Sun, Song; Lehec, Sharon; Dhawan, Anil; Hughes, Robin D

2015-12-01

Mesenchymal stem/stromal cells (MSCs) improve the metabolic function of co-cultured hepatocytes. The present study aimed to further enhance the trophic effects of co-culture with hepatocytes using hypoxic preconditioning (HPc) of the MSCs and also to investigate the underlying molecular mechanisms involved. Human adipose tissue-derived MSCs were subjected to hypoxia (2 % O2; HPc) or normoxia (20 % O2) for 24 h and then co-cultured with isolated human hepatocytes. Assays of metabolic function and apoptosis were performed to investigate the hepatotrophic and anti-apoptotic effects of co-culture. Indirect co-cultures and co-culture with MSC-conditioned medium investigated the role of paracrine factors in the hepatotrophic effects of co-culture. Reactive oxygen species (ROS) activity was antagonised with N-acetylcysteine to investigate whether HPc potentiated the effects of MSCs by intracellular ROS-dependent mechanisms. Tumour necrosis factor (TNF)-α, transforming growth factor (TGF)-β1, and extracellular collagen production was determined and CASP9 and BAX/BCL-2 signalling pathways analysed to investigate the role of soluble factors, extracellular matrix deposition, and apoptosis-associated gene signalling in the effects of co-culture. HPc potentiated the hepatotrophic and anti-apoptotic effects of co-culture by ROS-dependent mechanisms. There was increased MSC TGF-β1 production, and enhanced MSC deposition of extracellular collagen, with reduced synthesis of TNF-α, as well as a downregulation of the expression of pro-apoptotic CASP9, BAX, BID and BLK genes and upregulated expression of anti-apoptotic BCL-2 in hepatocytes. HPc potentiated the trophic and anti-apoptotic effects of MSCs on hepatocytes via mechanisms including intracellular ROS, autocrine TGF-β, extracellular collagen and caspase and BAX/BCL-2 signalling pathways.

Lentinan diminishes apoptotic bodies in the ileal crypts associated with S-1 administration.

PubMed

Suga, Yasuyo; Takehana, Kenji

2017-09-01

S-1 is an oral agent containing tegafur (a prodrug of 5-fluorouracil) that is used to treat various cancers, but adverse effects are frequent. Two pilot clinical studies have suggested that lentinan (LNT; β-1,3-glucan) may reduce the incidence of adverse effects caused by S-1 therapy. In this study, we established a murine model for assessment of gastrointestinal toxicity associated with S-1 and studied the effect of LNT. S-1 was administered orally to BALB/c mice at the effective dose (8.3mg/kg, as tegafur equivalent) once daily (5days per week) for 3weeks. Stool consistency and intestinal specimens were examined. We investigated the effect of combined intravenous administration of LNT at 0.1mg, which is an effective dose in murine tumor models. We also investigated the effect of a single administration of S-1. During long-term administration of S-1, some mice had loose stools and an increase in apoptotic bodies was observed in the ileal crypts. An increase in apoptotic bodies was also noted after a single administration of S-1 (15mg/kg). Prior or concomitant administration of LNT inhibited the increase in apoptotic bodies in both settings. Administration of LNT also increased the accumulation of CD11b + TIM-4 + cells in the ileum, while depletion of these cells by liposomal clodronate diminished the inhibitory effect of LNT on S-1 toxicity. Combined administration of LNT with S-1 led to a decrease in apoptotic bodies in the ileal crypts, possibly because LNT promoted phagocytosis of damaged cells by CD11b + TIM-4 + cells. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of pomelo citrus (Citrus maxima var. Nambangan), vitamin C and lycopene towards the number reduction of mice (Mus musculus) apoptotic hepatocyte caused of ochratoxin A

NASA Astrophysics Data System (ADS)

Badriyah, Hastuti, Utami Sri

2017-06-01

Foods can contaminated by some mycotoxin produced by molds. Ochratoxin A is a sort of mycotoxin that cause structural damage on hepatocytes. Pomelo citrus (Citrus maxima var. Nambangan) contain vitamin C and lycopene that have antioxidant character. This research is done to: 1)examine the effect of pomelo citrus juice, vitamin C, and lycopene treatment towards the number reduction of mice apoptotic hepatocytes caused by ochratoxin A exposure, 2)examine the effect of vitamin C mixed with lycopene treatment towards the number reduction of mice apoptotic hepatocytes caused by ochratoxin A exposure. The experimental group used male mice strain BALB-C in the age of three month and bodyweight 20-30 grams devided in 4 experiment group and control group. The experiment group I were administered pomelo citrus juice 0,5 ml/30 grams BW/day orally during 2 weeks and then administered with ochratoxin in the dose of 1 mg/kg BW during 1 week. The experiment group II were administered with vitamin C in the dose of 5,85 µg/30g BW with the same methods. The experiment group III were administered with lycopene in the dose of 0,1025 µg/30 g BW with the same methods. The experiment group IV were administered with vitamin C mixed with lycopene with the same methods. The control group were administered with ochratoxin A in the dose of 1 mg/kg BW per oral during 1 week. The apoptotic hepatocyte number were count by microscopic observation of hepatocyte slides from experiment group as well as control group with cytochemical staining. The research result shows that: 1) the pomelo citrus juice, vitamin C as well as lycopene administration could reduce the mice apoptotic hepatocyte number caused by ochratoxin A exposure, compared with the mice apoptotic hepatocyte number caused by ochratoxin A exposure only; 2) the vitamin C mixed with lycopene could reduce the mice apoptotic hepatocyte number caused by ochratoxin A exposure compared with the mice apoptotic hepatocyte number caused by ochratoxin exposure only.

Neurological Effects of Honey: Current and Future Prospects

PubMed Central

Mijanur Rahman, Mohammad; Gan, Siew Hua; Khalil, Md. Ibrahim

2014-01-01

Honey is the only insect-derived natural product with therapeutic, traditional, spiritual, nutritional, cosmetic, and industrial value. In addition to having excellent nutritional value, honey is a good source of physiologically active natural compounds, such as polyphenols. Unfortunately, there are very few current research projects investigating the nootropic and neuropharmacological effects of honey, and these are still in their early stages. Raw honey possesses nootropic effects, such as memory-enhancing effects, as well as neuropharmacological activities, such as anxiolytic, antinociceptive, anticonvulsant, and antidepressant activities. Research suggests that the polyphenol constituents of honey can quench biological reactive oxygen species and counter oxidative stress while restoring the cellular antioxidant defense system. Honey polyphenols are also directly involved in apoptotic activities while attenuating microglia-induced neuroinflammation. Honey polyphenols are useful in improving memory deficits and can act at the molecular level. Therefore, the ultimate biochemical impact of honey on specific neurodegenerative diseases, apoptosis, necrosis, neuroinflammation, synaptic plasticity, and behavior-modulating neural circuitry should be evaluated with appropriate mechanistic approaches using biochemical and molecular tools. PMID:24876885

Zyflamend Sensitizes Tumor Cells to TRAIL-Induced Apoptosis Through Up-Regulation of Death Receptors and Down-Regulation of Survival Proteins: Role of ROS-Dependent CCAAT/Enhancer-Binding Protein-Homologous Protein Pathway

PubMed Central

Kim, Ji Hye; Park, Byoungduck; Gupta, Subash C.; Kannappan, Ramaswamy; Sung, Bokyung

2012-01-01

Abstract Aim: TNF (tumor necrosis factor)-related apoptosis-inducing ligand (TRAIL), is a selective killer of tumor cells, although its potential is limited by the development of resistance. In this article, we investigated whether the polyherbal preparation Zyflamend® can sensitize tumor cells to TRAIL. Results: We found that Zyflamend potentiated TRAIL-induced apoptosis in human cancer cells. Zyflamend manifested its effects through several mechanisms. First, it down-regulated the expression of cell survival proteins known to be linked to resistance to TRAIL. Second, Zyflamend up-regulated the expression of pro-apoptotic protein, Bax. Third, Zyflamend up-regulated the expression of death receptors (DRs) for TRAIL. Up-regulation of DRs was critical as gene-silencing of these receptors significantly reduced the effect of Zyflamend on TRAIL-induced apoptosis. The up-regulation of DRs was dependent on CCAAT/enhancer-binding protein-homologous protein (CHOP), as Zyflamend induced CHOP, its gene-silencing abolished the induction of receptors, and mutation of the CHOP binding site on DR5 promoter abolished Zyflamend-mediated DR5 transactivation. Zyflamend mediated its effects through reactive oxygen species (ROS), as ROS quenching reduced its effect. Further, Zyflamend induced DR5 and CHOP and down-regulated the expression of cell survival proteins in nude mice bearing human pancreatic cancer cells. Innovation: Zyflamend can sensitize tumor cells to TRAIL through modulation of multiple cell signaling mechanisms that are linked to ROS. Conclusion: Zyflamend potentiates TRAIL-induced apoptosis through the ROS-CHOP-mediated up-regulation of DRs, increase in pro-apoptotic protein and down-regulation of cell survival proteins. Antioxid. Redox Signal. 16, 413–427. PMID:22004570

The Influence of Spirulina platensis Filtrates on Caco-2 Proliferative Activity and Expression of Apoptosis-Related microRNAs and mRNA.

PubMed

Śmieszek, Agnieszka; Giezek, Ewa; Chrapiec, Martyna; Murat, Martyna; Mucha, Aleksandra; Michalak, Izabela; Marycz, Krzysztof

2017-03-07

Spirulina platensis (SP) is a blue-green microalga that has recently raised attention not only as a nutritional component, but also as a source of bioactivities that have therapeutic effects and may find application in medicine, including cancer treatment. In the present study we determined the cytotoxic effect of S. platensis filtrates (SPF) on human colon cancer cell line Caco-2. Three concentrations of SPF were tested-1.25%, 2.5%, and 5% ( v / v ). We have found that the highest concentration of SPF exerts the strongest anti-proliferative and pro-apoptotic effect on Caco-2 cultures. The SPF negatively affected the morphology of Caco-2 causing colony shrinking and significant inhibition of metabolic and proliferative activity of cells. The wound-healing assay showed that the SPF impaired migratory capabilities of Caco-2. This observation was consistent with lowered mRNA levels for metalloproteinases. Furthermore, SPF decreased the transcript level of pro-survival genes (cyclin D1, surviving, and c-Myc) and reduced the autocrine secretion of Wnt-10b. The cytotoxic effect of SPF involved the modulation of the Bax and Bcl-2 ratio and a decrease of mitochondrial activity, and was related with increased levels of intracellular reactive oxygen species (ROS) and nitric oxide (NO). Moreover, the SPF also caused an increased number of cells in the apoptotic sub-G0 phase and up-regulated expression of mir-145, simultaneously decreasing expression of mir-17 and 146. Obtained results indicate that SPF can be considered as an agent with anti-cancer properties that may be used for colon cancer prevention and treatment.

The Influence of Spirulina platensis Filtrates on Caco-2 Proliferative Activity and Expression of Apoptosis-Related microRNAs and mRNA

PubMed Central

Śmieszek, Agnieszka; Giezek, Ewa; Chrapiec, Martyna; Murat, Martyna; Mucha, Aleksandra; Michalak, Izabela; Marycz, Krzysztof

2017-01-01

Spirulina platensis (SP) is a blue-green microalga that has recently raised attention not only as a nutritional component, but also as a source of bioactivities that have therapeutic effects and may find application in medicine, including cancer treatment. In the present study we determined the cytotoxic effect of S. platensis filtrates (SPF) on human colon cancer cell line Caco-2. Three concentrations of SPF were tested—1.25%, 2.5%, and 5% (v/v). We have found that the highest concentration of SPF exerts the strongest anti-proliferative and pro-apoptotic effect on Caco-2 cultures. The SPF negatively affected the morphology of Caco-2 causing colony shrinking and significant inhibition of metabolic and proliferative activity of cells. The wound-healing assay showed that the SPF impaired migratory capabilities of Caco-2. This observation was consistent with lowered mRNA levels for metalloproteinases. Furthermore, SPF decreased the transcript level of pro-survival genes (cyclin D1, surviving, and c-Myc) and reduced the autocrine secretion of Wnt-10b. The cytotoxic effect of SPF involved the modulation of the Bax and Bcl-2 ratio and a decrease of mitochondrial activity, and was related with increased levels of intracellular reactive oxygen species (ROS) and nitric oxide (NO). Moreover, the SPF also caused an increased number of cells in the apoptotic sub-G0 phase and up-regulated expression of mir-145, simultaneously decreasing expression of mir-17 and 146. Obtained results indicate that SPF can be considered as an agent with anti-cancer properties that may be used for colon cancer prevention and treatment. PMID:28272349

Effects of femara and tamoxifen on proliferation of FM3A cells in culture.

PubMed

Topcul, Mehmet; Topcul, Funda; Cetin, Idil

2013-01-01

In this study, antiproliferative effects of the selective estrogen receptor modulator Tamoxifen and the aromatase inhibitor letrozole (Femara) were evaluated and compared using the FM3A cell line, originating from a C3H mouse mammary carcinoma and positive in terms of estrogen receptor (ER) expression. Cell kinetic parameters including labelling index, mitotic index and labelling index were assessed after exposure of the. FM3A cell line to 0.001μg/ml of Tamoxifen and 0.25μg/ml of Femara for 4, 8, 16 and 32 h for all parameters. The results showed that cell growth was inhibited by both agents. There was a significant decrease in labelling index and mitotic index and significant increase in apoptotic index for all experimental groups. The differences between control and all experimental groups were statistically significant (p<0.001) for all applications.

Ras activation modulates methylglyoxal-induced mesangial cell apoptosis through superoxide production.

PubMed

Huang, Wei Jan; Tung, Chun Wu; Ho, Cheng; Yang, Jen Tsung; Chen, Min Li; Chang, Pey Jium; Lee, Pei Hsien; Lin, Chun Liang; Wang, Jeng Yi

2007-01-01

While previous studies have demonstrated that diabetic nephropathy is attributable to glucose-derived dicarbonyl compounds, methylglyoxal (MGO)-inducing apoptosis in renal mesangial cells, the molecular mechanism of upper stream redox signaling modulation, has not been fully elucidated. Rat mesangial cells pretreated with or without superoxide dismutase, diphenyloniodium, SB203580, and manumycin A were cultured in methylglyoxal stress-induced apoptosis. Signaling protein expression, flow cytometry, and morphological features of apoptotic cell death were assessed. Methylglyoxal decreased cell viability in mesangial cells. Superoxide mediated methylglyoxal-induced caspase 3 cleavage. Pretreatment with diphenyloniodium, SB203580, and manumycin A reduced methylglyoxal augmentation of superoxide synthesis and caspase-3 activation. Methylglyoxal rapidly enhanced Ras activation and progressively increased cytosolic P38 and nuclear c-Jun activation. Scavenging of superoxide by superoxide dismutase or diphenyloniodium, inhibiting P38 by SB203580, and inhibiting Ras with manumycin A successfully reduced the promoting effect of methylglyoxal on P38 and c-Jun phosphorylation (activation). Furthermore, pretreatment with superoxide dismutase, diphenyloniodium, SB203580, and manumycin A significantly attenuated methylglyoxal induction of apoptosis on the basis of Annexin-V assay and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labelling (TUNEL) staining. This study has shown that methylglyoxal increased Ras modulation of superoxide-mediated P38 activation and c-Jun activation, which resulted in increased apoptosis.

The effect of N-nitrosodimethylamine (NDMA) on Bax and Mcl-1 expression in human neutrophils.

PubMed

Jablonski, Jakub; Jablonska, Ewa; Leonik, Agnieszka

2011-12-01

In the present study we examined a role of pro-apoptotic Bax and anti-apoptotic Mcl-1 proteins, participating in the regulation of intrinsic apoptosis pathway in human neutrophils (PMNs) exposed to N-nitrosodimethylamine (NDMA), the environmental xenobiotic. For the purpose comparison, the same studies were conducted in autologous peripheral blood mononuclear cells (PBMCs). The production of cytochrome c by PMNs was also determined. A deficit of anti-apoptotic Mcl-1 and overexpression of the pro-apoptotic protein Bax suggest that the apoptosis process in human neutrophils exposed to NDMA is dependent on changes in the expression of these proteins. PMNs were more sensitive to NDMA than PBMCs.

Modulation of cutaneous scavenger receptor B1 levels by exogenous stressors impairs "in vitro" wound closure.

PubMed

Muresan, Ximena Maria; Sticozzi, Claudia; Belmonte, Giuseppe; Savelli, Vinno; Evelson, Pablo; Valacchi, Giuseppe

2018-06-01

Scavenger receptor B1 (SR-B1) is a trans-membrane protein, involved in tissue reverse cholesterol transport. Several studies have demonstrated that SR-B1 is also implicated in other physiological processes, such as bacteria and apoptotic cells recognition and regulation of intracellular tocopherol and carotenoids levels. Among the tissues where it is localized, SR-B1 has been shown to be significantly expressed in human epidermis. Our group has demonstrated that SR-B1 levels are down-regulated in human cultured keratinocytes by environmental stressors, such as cigarette smoke, via cellular redox imbalance. Our present study aimed to investigate whether such down-regulation was confirmed in a 3D skin model and under other environmental challengers such as particulate matter and ozone. We also investigated the association between oxidation-induced SR-B1 modulation and impaired wound closure. The data obtained showed that not only cigarette, but also the other environmental stressors reduced SR-B1 expression in epidermal cutaneous tissues and that this effect might be involved in impaired wound healing. Published by Elsevier B.V.

The effect of newly synthesized progesterone derivatives on apoptotic and angiogenic pathway in MCF-7 breast cancer cells.

PubMed

Yahya, Shaymaa M M; Abdelhamid, Abdou O; Abd-Elhalim, Mervat M; Elsayed, Ghada H; Eskander, Emad F

2017-10-01

Due to its high potency and selectivity, anticancer agents consisting of combined molecules have gained great interests. The current study introduces newly synthesized progesterone derivatives of promising anticancer effect. Moreover, the pro-apoptotic and anti-angiogenic effects of these compounds were studied extensively. Several thiazole, pyridine, pyrazole, thiazolopyridine and pyrazolopyridine progesterone derivatives were synthesized. The structure of the novel progesterone derivatives was elucidated and confirmed using the analytical and spectral data. This novel derivatives were tested for their cytotoxic effect against human breast cancer cells (MCF-7) using neutral red uptake assay. Tested compounds showed anticancer activity against MCF-7 cancer cell line in the descending order of 7>2>3>8>6>9>4. The expression levels of Bcl-2, survivin, CCND1, CDC2, P53 and P21, VEGF, Hif-1α, MMP-2, MMP-9, Ang-1, Ang-2, and FGF-1 genes were investigated using QRT-PCR (Quantitative real time-polymerase chain reaction). The study clarified that compounds 2, 3, 4, 6, 7, 8 and 9 showed significant pro-apoptotic effect through the down regulation of Bcl-2., besides, survivin and CCND1 expression levels were down regulated by compounds 3, 4, 6, 7, 8, 9. However, Compound 4 may exert this pro-apoptotic effect through the up-regulation of P53 gene expression. On the other hand, the anti-angiogenic effect of these newly synthesized derivatives was due to their down regulation of VEGF, Ang-2, MMP-9 and FGF-1; and the up-regulation of HIF-1α and ang-1. This study recommended promising pro-apoptotic and anti-angiogenic anticancer agents acting through the regulation of key regulators of apoptosis, cell cycle genes, and pro-angiogenic genes. Copyright © 2017 Elsevier Inc. All rights reserved.

Apoptosis induction by silica nanoparticles mediated through reactive oxygen species in human liver cell line HepG2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahmad, Javed; Ahamed, Maqusood, E-mail: maqusood@gmail.com; Akhtar, Mohd Javed

Silica nanoparticles are increasingly utilized in various applications including agriculture and medicine. In vivo studies have shown that liver is one of the primary target organ of silica nanoparticles. However, possible mechanisms of hepatotoxicity caused by silica nanoparticles still remain unclear. In this study, we explored the reactive oxygen species (ROS) mediated apoptosis induced by well-characterized 14 nm silica nanoparticles in human liver cell line HepG2. Silica nanoparticles (25–200 μg/ml) induced a dose-dependent cytotoxicity in HepG2 cells. Silica nanoparticles were also found to induce oxidative stress in dose-dependent manner indicated by induction of ROS and lipid peroxidation and depletion ofmore » glutathione (GSH). Quantitative real-time PCR and immunoblotting results showed that both the mRNA and protein expressions of cell cycle checkpoint gene p53 and apoptotic genes (bax and caspase-3) were up-regulated while the anti-apoptotic gene bcl-2 was down-regulated in silica nanoparticles treated cells. Moreover, co-treatment of ROS scavenger vitamin C significantly attenuated the modulation of apoptotic markers along with the preservation of cell viability caused by silica nanoparticles. Our data demonstrated that silica nanoparticles induced apoptosis in human liver cells, which is ROS mediated and regulated through p53, bax/bcl-2 and caspase pathways. This study suggests that toxicity mechanisms of silica nanoparticles should be further investigated at in vivo level. -- Highlights: ► We explored the mechanisms of toxicity caused by silica NPs in human liver HepG2 cells. ► Silica NPs induced a dose-dependent cytotoxicity in HepG2 cells. ► Silica NPs induced ROS generation and oxidative stress in a dose-dependent manner. ► Silica NPs were also modulated apoptosis markers both at mRNA and protein levels. ► ROS mediated apoptosis induced by silica NPs was preserved by vitamin C.« less

L-Arginine Modulates Intestinal Inflammation in Rats Submitted to Mesenteric Ischemia-Reperfusion Injury.

PubMed

Taha, M O; de Oliveira, J V; Dias Borges, M; de Lucca Melo, F; Gualtieri, F G; E Silva Aidar, A L; Pacheco, R L; de Melo Alexandre E Silva, T; Klajner, R K; Iuamoto, L R; Munhoz Torres, L; Morais Mendes de Paula, B J; de Campos, K; Oliveira-Junior, I S; Fagundes, D J

2016-03-01

The goal of this study was to investigate whether exogenous offer of L-arginine (LARG) modulates the gene expression of intestinal dysfunction caused by ischemia and reperfusion. Eighteen Wistar-EPM1 male rats (250-300 g) were anesthetized and subjected to laparotomy. The superior mesenteric vessels were exposed, and the rats were randomized into 3 groups (n = 6): the control group (CG), with no superior mesenteric artery interruption; the ischemia/reperfusion group (IRG), with 60 minutes of ischemia and 120 minutes of reperfusion and saline injections; and the L-arginine group (IRG + LARG), with L-arginine injected in the femoral vein 5 minutes before ischemia, 5 minutes after reperfusion, and after 55 minutes of reperfusion. The total RNA was extracted and purified from samples of the small intestine. The concentration of each total RNA sample was determined by using spectrophotometry. The first-strand complementary DNA (cDNA) was synthesized in equal amounts of cDNA and the Master Mix SYBR Green qPCR Mastermix (SABiosciences, a Qiagen Company, Frederick, Md). Amounts of cDNA and Master Mix SYBR Green qPCR Mastermix were distributed to each well of the polymerase chain reaction microarray plate containing the predispensed gene-specific primer sets for Bax and Bcl2. Each sample was evaluated in triplicate, and the Student t test was applied to validate the homogeneity of each gene expression reaction (P < .05). The gene expression of Bax in IRG (+1.48) was significantly higher than in IRG-LARG (+9.69); the expression of Bcl2L1 in IRG (+1.01) was significantly higher than IRG-LARG (+22.89). The apoptotic cell pathway of 2 protagonists showed that LARG improves the gene expression of anti-apoptotic Bcl2l1 (Bcl2-like 1) more than the pro-apoptotic Bax (Bcl2-associated X protein). Copyright © 2016. Published by Elsevier Inc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, De-Ju; Xu, Yan-Ming; Du, Ji-Ying

Highlights: • Normal human bronchial epithelial cells (BEAS-2B) were dosed with cadmium (Cd). • A low level (2 μM) of Cd treatment for 36 h elicited negligible cytotoxicity. • High levels (20 or 30 μM) of Cd treatment for 36 h induced cell death. • High levels of Cd can upregulate the protein levels of eIF5A1 and NF-κB p65. • We suggest that eIF5A1 level is possibly modulated by NF-κB. - Abstract: Cadmium (Cd) and Cd compounds are widely-distributed in the environment and well-known carcinogens. Here, we report that in CdCl{sub 2}-exposed human bronchial epithelial cells (BEAS-2B), the level ofmore » p53 is dramatically decreased in a time- and dose-dependent manner, suggesting that the observed Cd-induced cytotoxicity is not likely due to the pro-apoptotic function of p53. Therefore, this prompted us to further study the responsive pro-apoptotic factors by proteomic approaches. Interestingly, we identified that high levels (20 or 30 μM) of Cd can significantly upregulate the protein levels of eukaryotic translation initiation factor 5A1 (eIF5A1) and redox-sensitive transcription factor NF-κB p65. Moreover, there is an enhanced NF-κB nuclear translocation as well as chromatin-binding in Cd-treated BEAS-2B cells. We also show that small interfering RNA-specific knockdown of eIF5A1 in Cd-exposed cells attenuated the Cd cytotoxicity, indicating the potential role of eIF5A1 in Cd cytotoxicity. As eIF5A1 is reported to be related with cell apoptosis but little is known about its transcriptional control, we hypothesize that NF-κB might likely modulate eIF5A1 gene expression. Notably, by bioinformatic analysis, several potential NF-κB binding sites on the upstream promoter region of eIF5A1 gene can be found. Subsequent chromatin immunoprecipitation assay revealed that indeed there is enhanced NF-κB binding on eIF5A1 promoter region of Cd-treated BEAS-2B cells. Taken together, our findings suggest for the first time a regulatory mechanism for the pro-apoptotic protein eIF5A1 in which its level is possibly modulated by NF-κB in human lung cells.« less

Therapeutic properties of green tea against environmental insults

PubMed Central

Chen, Lixia; Mo, Huanbiao; Zhao, Ling; Gao, Weimin; Wang, Shu; Cromie, Meghan M; Lu, Chuanwen; Wang, Jia-Sheng; Shen, Chwan-Li

2016-01-01

Pesticides, smoke, mycotoxins, polychlorinated biphenyls, and arsenic are the most common environmental toxins and toxicants to humans. These toxins and toxicants may impact on human health at the molecular (DNA, RNA, or protein), organelle (mitochondria, lysosome, or membranes), cellular (growth inhibition or cell death), tissue, organ, and systemic levels. Formation of reactive radicals, lipid peroxidation, inflammation, genotoxicity, hepatotoxicity, embryotoxicity, neurological alterations, apoptosis, and carcinogenic events are some of the mechanisms mediating the toxic effects of the environmental toxins and toxicants. Green tea, the non-oxidized and non-fermented form of tea that contains several polyphenols, including green tea catechins, exhibits protective effects against these environmental toxins and toxicants in preclinical studies and to a much-limited extent, in clinical trials. The protective effects are collectively mediated by antioxidant, anti-inflammatory, anti-mutagenic, hepato- and neuroprotective, and anti-carcinogenic activities. In addition, green tea modulates signaling pathway including NFκB and ERK pathways, preserves mitochondrial membrane potential, inhibits caspase-3 activity, down-regulates pro-apoptotic proteins, and induces the phase II detoxifying pathway. The bioavailability and metabolism of green tea and its protective effects against environmental insults induced by pesticides, smoke, mycotoxins, polychlorinated biphenyls, and arsenic are reviewed in this paper. Future studies with emphasis on clinical trials should identify biomarkers of green tea intake, examine the mechanisms of action of green tea polyphenols, and investigate potential interactions of green tea with other toxicant-modulating dietary factors. PMID:27723473

DNA damage induces down-regulation of Prp19 via impairing Prp19 stability in hepatocellular carcinoma cells.

PubMed

Yin, Jie; Zhang, Yi-An; Liu, Tao-Tao; Zhu, Ji-Min; Shen, Xi-Zhong

2014-01-01

Pre-mRNA processing factor 19 (Prp19) activates pre-mRNA spliceosome and also mediates DNA damage response. Prp19 overexpression in cells with functional p53 leads to decreased apoptosis and increases cell survival after DNA damage. Here we showed that in hepatocellular carcinoma (HCC) cells with inactive p53 or functional p53, Prp19 was down-regulated due to the impaired stability under chemotherapeutic drug treatment. Silencing Prp19 expression enhanced apoptosis of HCC cells with or without chemotherapeutic drug treatment. Furthermore high level of Prp19 may inhibit chemotherapeutic drugs induced apoptosis in hepatocellular carcinoma cells through modulating myeloid leukemia cell differentiation 1 expression. These results indicated that targeting Prp19 may potentiate pro-apoptotic effect of chemotherapeutic agents on HCC.

Berberine induces autophagy in glioblastoma by targeting the AMPK/mTOR/ULK1-pathway

PubMed Central

Wang, Jiwei; Qi, Qichao; Feng, Zichao; Zhang, Xin; Huang, Bin; Chen, Anjing; Prestegarden, Lars; Li, Xingang; Wang, Jian

2016-01-01

There is an urgent need for new therapeutic strategies for patients with glioblastoma multiforme (GBM). Previous studies have shown that berberine (BBR), a natural plant alkaloid, has potent anti-tumor activity. However, the mechanisms leading to cancer cell death have not been clearly elucidated. In this study, we show that BBR has profound effects on the metabolic state of GBM cells, leading to high autophagy flux and impaired glycolytic capacity. Functionally, these alterations reduce the invasive properties, proliferative potential and induce apoptotic cell death. The molecular alterations preceding these changes are characterized by inhibition of the AMPK/mTOR/ULK1 pathway. Finally, we demonstrate that BBR significantly reduces tumor growth in vivo, demonstrating the potential clinical benefits for autophagy modulating plant alkaloids in cancer therapy. PMID:27557493

Cytotoxic and pro-oxidative effects of Imperata cylindrica aerial part ethyl acetate extract in colorectal cancer in vitro.

PubMed

Kwok, Amy Ho Yan; Wang, Yan; Ho, Wing Shing

2016-05-15

Colorectal cancer (CRC) is the third most common cancer. Its global incidence and mortality have been on the rise. Recent strategy of therapies has involved the use of non-steroid anti-inflammatory drugs and cyclooxygenase-selective inhibitors. Aerial parts of Imperata cylindrical L. Raeusch (IMP) have been used as an anti-inflammatory agent in traditional Chinese medicine. Asarachidonate acid cascadeis often involved in inflammation-related malignancy and IMP is an anti-inflammatory agent, hence it is hypothesized that IMP aerial part ethyl acetate extract exerts cytotoxic effects on colorectal cancer cells in vitro. The HT-29 adenocarcinoma cell line was used to elucidate its pro-apoptotic activities. Flow cytometry and fluorescent microscopy were performed to assess cell cycle arrest and the accumulation of reactive oxygen species (ROS). The mRNA and hormone levels of arachidonate acid pathways were studied via quantitative reverse transcription PCR (qRT-PCR) and ELISA. The 50% growth inhibitory effect (GI50) of the IMP extract on HT-29 was measured with a value of 14.5 µg/ml. Immuno-blot and caspase-3/7 activity assay showed the pro-apoptotic effect of IMP on the activation of caspase cascade. G2/M arrest was observed via flow cytometry. The ROS activity was modulated by the IMP extraction a concentration-dependent manner in HT-29 cells. The IMP extract increased PGE2 and PGF2α levels qRT-PCR revealed that transcripts of rate-limiting PGE2- and PGF2α-biosynthetic enzymes - COX-1, mPGES1 and AKR1C3 were notably up-regulated. Among the prostanoid receptors, EP1 and FP transcripts were up-regulated while EP4 transcripts decreased. The findings suggest that the proliferative effect of PGE2, which is generally believed to associate with heightened DNA synthesis and cross-talk with MAPK pathways, is likely triggered by the pro-apoptotic or -oxidative effects exerted by IMP extract in HT-29 cells. Concurring with this notion, indomethacin (COX-1/2-inhibitor) was demonstrated to potentiate the cytotoxic effect of IMP extract (GI50 ≦ 10.8 µg/ml). The results show that the cytotoxic effect of IMP extract predominates over the influence of proliferative prostanoids released by challenged colorectal cancer cells, and may present a potential source for development of novel anti-cancer drugs. Copyright © 2016 Elsevier GmbH. All rights reserved.

Peptide-Based Photoelectrochemical Cytosensor Using a Hollow-TiO2/EG/ZnIn2S4 Cosensitized Structure for Ultrasensitive Detection of Early Apoptotic Cells and Drug Evaluation.

PubMed

Wu, Rong; Fan, Gao-Chao; Jiang, Li-Ping; Zhu, Jun-Jie

2018-02-07

The ability to rapidly detect apoptotic cells and accurately evaluate therapeutic effects is significant in cancer research. To address this target, a biocompatible, ultrasensitive photoelectrochemical (PEC) cytosensing platform was developed based on electrochemically reduced graphene (EG)/ZnIn 2 S 4 cosensitized TiO 2 coupled with specific recognition between apoptotic cells and phosphatidylserine-binding peptide (PSBP). In this strategy, the HL-60 cells were selected as a model and C005, nilotinib, and imatinib were selected as apoptosis inducers to show cytosensing performances. In particular, a TiO 2 photoactive substrate was designed as hollow spheres to enhance the PEC performance. Graphene was electrodeposited on the hollow TiO 2 -modified electrode to accelerate electron transfer and increase conductivity, followed by in situ growth of ZnIn 2 S 4 nanocrystals as photosensitizers via successive ionic layer adsorption and reaction method, forming a TiO 2 /EG/ZnIn 2 S 4 cosensitized structure that was used as a PEC matrix to immobilize PSBP for the recognition of early apoptotic cells. The detection of apoptotic cells was based on steric hindrance originating from apoptotic cell capture to induce an obvious decrease in the photocurrent signal. The ultrahigh sensitivity of the cytosensor resulted from enhanced PEC performance, bioactivity, and high binding affinity between PSBP and apoptotic cells. Compared with other assays, incorporate toxic elements were avoided, such as Cd, Ru, and Te, which ensured normal cell growth and are appropriate for cell analysis. The designed PEC cytosensor showed a low detection limit of apoptotic cells (as low as three cells), a wide linear range from 1 × 10 3 to 5 × 10 7 cells/mL, and an accurate evaluation of therapeutic effects. It also exhibited good specificity, reproducibility, and stability.

Cytotoxic, antioxidative, genotoxic and antigenotoxic effects of Horchata, beverage of South Ecuador.

PubMed

Bailon-Moscoso, Natalia; Tinitana, Fani; Martínez-Espinosa, Ruth; Jaramillo-Velez, Andrea; Palacio-Arpi, Alejandra; Aguilar-Hernandez, Jessica; Romero-Benavides, Juan Carlos

2017-12-19

"Horchata" is an herbal mixture infusion consumed in Southern Ecuador; 66% of its plants are anti-inflammatory medicinal plant, and 51% are analgesics. Anti-inflammatory substances can prevent carcinogenesis mediated by cytotoxic effects and can prevent DNA damage. The aim of this study was to evaluate the cytotoxicity and apoptotic/antigenotoxic effects of horchata as well as its mechanism. Nine different varieties of horchata were prepared in the traditional way and then freeze-dried. Phytochemical screening tested for the presence of secondary metabolites using standard procedures and antioxidant activities. The cytotoxic activity was evaluated on cerebral astrocytoma (D-384), prostate cancer (PC-3), breast cancer (MCF-7), colon cancer (RKO), lung cancer (A-549), immortalized Chinese hamster ovary cells (CHO-K1), and human peripheral blood lymphocytes via a MTS assay. The pro-apoptotic effects were evaluated with Anexin V/Propidium Iodide and western blot of Bax, Bcl-2, TP53, and TP73. Induction and reduction of ROS were assessed by fluorimetry. Genotoxic and antigenotoxic effects were evaluated with a comet assay and micronuclei on binucleated cells. Five of nine horchatas had cytotoxic effects against D-384 while not affecting normal cells. These horchatas induce cell death by apoptosis modulated by p53/p73. In CHO-K1 cells, the horchatas decrease the damage induced by hydrogen peroxide and Mitomycin C measured in the comet and micronucleus assay respectively. The IC 50 range of effective horchatas in D-384 was 41 to 122 μg·mL -1 . This effect may be related to its use in traditional medicine (brain tonic). On the other hand, immortalized Chinese hamster ovary cells (CHO-K1) and lymphocytes did not show a cytotoxic effect. The most potent horchata induced apoptosis via a p53/p73-mediated mechanism. The horchatas present antigenotoxic properties, which may be related to the antioxidant capacity. Future studies on horchata components are necessary to understand the interactions and beneficial properties.

Mitochondria As Sources and Targets of Methane.

PubMed

Mészáros, András Tamás; Szilágyi, Ágnes Lilla; Juhász, László; Tuboly, Eszter; Érces, Dániel; Varga, Gabriella; Hartmann, Petra

2017-01-01

This review summarizes the current knowledge on the role of mitochondria in the context of hypoxic cell biology, while providing evidence of how these mechanisms are modulated by methane (CH 4 ). Recent studies have unambiguously confirmed CH 4 bioactivity in various in vitro and in vivo experimental models and established the possibility that CH 4 can affect many aspects of mitochondrial physiology. To date, no specific binding of CH 4 to any enzymes or receptors have been reported, and it is probable that many of its effects are related to physico-chemical properties of the non-polar molecule. (i) Mitochondria themselves can be sources of endogenous CH 4 generation under oxido-reductive stress conditions; chemical inhibition of the mitochondrial electron transport chain with site-specific inhibitors leads to increased formation of CH 4 in eukaryote cells, in plants, and in animals. (ii) Conventionally believed as physiologically inert, studies cited in this review demonstrate that exogenous CH 4 modulates key events of inflammation. The anti-apoptotic effects of exogenously administered CH 4 are also recognized, and these properties also suggest that CH 4 -mediated intracellular signaling is closely associated with mitochondria. (iii) Mitochondrial substrate oxidation is coupled with the reduction of molecular oxygen, thus providing energy for cellular metabolism. Interestingly, recent in vivo studies have shown improved basal respiration and modulated mitochondrial oxidative phosphorylation by exogenous CH 4 . Overall, these data suggest that CH 4 liberation and effectiveness in eukaryotes are both linked to hypoxic events and redox regulation and support the notion that CH 4 has therapeutic roles in mammalian pathophysiologies.

Mitochondria As Sources and Targets of Methane

PubMed Central

Mészáros, András Tamás; Szilágyi, Ágnes Lilla; Juhász, László; Tuboly, Eszter; Érces, Dániel; Varga, Gabriella; Hartmann, Petra

2017-01-01

This review summarizes the current knowledge on the role of mitochondria in the context of hypoxic cell biology, while providing evidence of how these mechanisms are modulated by methane (CH4). Recent studies have unambiguously confirmed CH4 bioactivity in various in vitro and in vivo experimental models and established the possibility that CH4 can affect many aspects of mitochondrial physiology. To date, no specific binding of CH4 to any enzymes or receptors have been reported, and it is probable that many of its effects are related to physico-chemical properties of the non-polar molecule. (i) Mitochondria themselves can be sources of endogenous CH4 generation under oxido-reductive stress conditions; chemical inhibition of the mitochondrial electron transport chain with site-specific inhibitors leads to increased formation of CH4 in eukaryote cells, in plants, and in animals. (ii) Conventionally believed as physiologically inert, studies cited in this review demonstrate that exogenous CH4 modulates key events of inflammation. The anti-apoptotic effects of exogenously administered CH4 are also recognized, and these properties also suggest that CH4-mediated intracellular signaling is closely associated with mitochondria. (iii) Mitochondrial substrate oxidation is coupled with the reduction of molecular oxygen, thus providing energy for cellular metabolism. Interestingly, recent in vivo studies have shown improved basal respiration and modulated mitochondrial oxidative phosphorylation by exogenous CH4. Overall, these data suggest that CH4 liberation and effectiveness in eukaryotes are both linked to hypoxic events and redox regulation and support the notion that CH4 has therapeutic roles in mammalian pathophysiologies. PMID:29181377

Clearance of apoptotic photoreceptors: elimination of apoptotic debris into the subretinal space and macrophage-mediated phagocytosis via phosphatidylserine receptor and integrin alphavbeta3.

PubMed

Hisatomi, Toshio; Sakamoto, Taiji; Sonoda, Koh-Hei; Tsutsumi, Chikako; Qiao, Hong; Enaida, Hiroshi; Yamanaka, Ichiro; Kubota, Toshiaki; Ishibashi, Tatsuro; Kura, Shinobu; Susin, Santos A; Kroemer, Guido

2003-06-01

The effective phagocytotic clearance of apoptotic debris is fundamental to the maintenance of neural tissues during apoptosis. Retinal photoreceptors undergo apoptosis after retinal detachment. Although their induction phase of apoptosis has been well discussed, their phagocytotic process remains quite unclear. We herein demonstrate that apoptotic photoreceptors are selectively eliminated from their physiological localization, the outer nuclear layer, to the subretinal space, and then phagocytosed by monocyte-derived macrophages. This could be shown by an ultrastructural and immunophenotypic analysis. Moreover, in chimera mice expressing transgenic green fluorescent protein in bone marrow-derived cells, the local infiltration of macrophages could be detected after retinal detachment-induced photoreceptor apoptosis. The local injection of an antibody blocking the phosphatidylserine receptor (PSR) or a peptide (GRGDSP)-blocking integrin alphavbeta3 revealed that phagocytotic clearance involves the PSR as well as integrin alphavbeta3 in vivo. Importantly, the level of blockade obtained with these reagents was different. Although anti-PSR increased the frequency of apoptotic cells that fail to bind to macrophages, GRGDSP prevented the engulfment (but not the recognition) of apoptotic photoreceptor cells by macrophages. To our knowledge, this is the first report describing the mechanisms through which apoptotic photoreceptors are selectively eliminated via a directional process in the subretinal space.

Caspase dependent apoptotic inhibition of melanoma and lung cancer cells by tropical Rubus extracts.

PubMed

George, Blassan Plackal Adimuriyil; Abrahamse, Heidi; Hemmaragala, Nanjundaswamy M

2016-05-01

Rubus fairholmianus Gard. inhibits human melanoma (A375) and lung cancer (A549) cell growth by the caspase dependent apoptotic pathway. Herbal products have a long history of clinical use and acceptance. They are freely available natural compounds that can be safely used to prevent various ailments. The plants and plant derived products became the basis of traditional medicine system throughout the world for thousands of years. The effects of R. fairholmianus root acetone extract (RFRA) on the proliferation of A375 and A549 cells was examined in this study. RFRA led to a decrease in cell viability, proliferation and an increase in cytotoxicity in a dose dependent manner when compared with control and normal skin fibroblast cells (WS1). The morphology of treated cells supported apoptotic cell death. Annexin V/propidium iodide staining indicated that RFRA induced apoptosis in A375 and A549 cells and the percentages of early and late apoptotic populations significantly increased. Moreover, the apoptotic inducing ability of RFRA when analysing effector caspase 3/7 activity, indicated a marked increase in treated cells. In summary, we have shown the anticancer effects of RFRA in A375 and A549 cancer cells via induction of caspase dependent apoptosis in vitro. The extract is more effective against melanoma; which may suggest the usefulness of RFRA-based anticancer therapies. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Apoptotic Cell Death Induced by Resveratrol Is Partially Mediated by the Autophagy Pathway in Human Ovarian Cancer Cells

PubMed Central

Lang, Fangfang; Qin, Zhaoyang; Li, Fang; Zhang, Huilin; Fang, Zhenghui; Hao, Enkui

2015-01-01

Resveratrol (trans-3,4,5’ –trihydroxystilbene) is an active compound in food, such as red grapes, peanuts, and berries. Resveratrol exhibits an anticancer effect on various human cancer cells. However, the mechanism of resveratrol-induced anti-cancer effect at the molecular level remains to be elucidated. In this study, the mechanism underlying the anti-cancer effect of resveratrol in human ovarian cancer cells (OVCAR-3 and Caov-3) was investigated using various molecular biology techniques, such as flow cytometry, western blotting, and RNA interference, with a major focus on the potential role of autophagy in resveratrol-induced apoptotic cell death. We demonstrated that resveratrol induced reactive oxygen species (ROS) generation, which triggers autophagy and subsequent apoptotic cell death. Resveratrol induced ATG5 expression and promoted LC3 cleavage. The apoptotic cell death induced by resveratrol was attenuated by both pharmacological and genetic inhibition of autophagy. The autophagy inhibitor chloroquine, which functions at the late stage of autophagy, significantly reduced resveratrol-induced cell death and caspase 3 activity in human ovarian cancer cells. We also demonstrated that targeting ATG5 by siRNA also suppressed resveratrol-induced apoptotic cell death. Thus, we concluded that a common pathway between autophagy and apoptosis exists in resveratrol-induced cell death in OVCAR-3 human ovarian cancer cells. PMID:26067645

Yeast Genetics for Delineating Bax/Bcl Pathway of Cell Death Regulation.

DTIC Science & Technology

1998-07-01

differences in tosol. The cytosol also became electron dense ("cyto- the copy number of the episomal plasmid from which solic condensation"), similar to...Cell Death & Differ . 3, 229-236. (1993). The C. eheans cell death gene ccd-3 encodes a protein similar ¶Xhitc. K., Tahaoglu, E., and Steller, H. (1996...components may be used in different functional contexts. Similar modules might exist in metazoan apoptotic pathways. Even though yeast does not contain

The activity of the anti-apoptotic fragment generated by the caspase-3/p120 RasGAP stress-sensing module displays strict Akt isoform specificity.

PubMed

Vanli, Güliz; Peltzer, Nieves; Dubuis, Gilles; Widmann, Christian

2014-12-01

The caspase-3/p120 RasGAP module acts as a stress sensor that promotes pro-survival or pro-death signaling depending on the intensity and the duration of the stressful stimuli. Partial cleavage of p120 RasGAP generates a fragment, called fragment N, which protects stressed cells by activating Akt signaling. Akt family members regulate many cellular processes including proliferation, inhibition of apoptosis and metabolism. These cellular processes are regulated by three distinct Akt isoforms: Akt1, Akt2 and Akt3. However, which of these isoforms are required for fragment N mediated protection have not been defined. In this study, we investigated the individual contribution of each isoform in fragment N-mediated cell protection against Fas ligand induced cell death. To this end, DLD1 and HCT116 isogenic cell lines lacking specific Akt isoforms were used. It was found that fragment N could activate Akt1 and Akt2 but that only the former could mediate the protective activity of the RasGAP-derived fragment. Even overexpression of Akt2 or Akt3 could not rescue the inability of fragment N to protect cells lacking Akt1. These results demonstrate a strict Akt isoform requirement for the anti-apoptotic activity of fragment N. Copyright © 2014 Elsevier Inc. All rights reserved.

Deletion of CXCR4 in cardiomyocytes exacerbates cardiac dysfunction following isoproterenol administration

PubMed Central

Wang, ER; Jarrah, AA; Benard, L; Chen, J; Schwarzkopf, M; Hadri, L; Tarzami, ST

2014-01-01

Altered alpha- and beta-adrenergic receptor signaling is associated with cardiac hypertrophy and failure. Stromal cell-derived factor-1α (SDF-1α) and its cognate receptor CXCR4 have been reported to mediate cardioprotection after injury through the mobilization of stem cells into injured tissue. However, little is known regarding whether SDF-1/CXCR4 induces acute protection following pathological hypertrophy and if so, by what molecular mechanism. We have previously reported that CXCR4 physically interacts with the beta-2 adrenergic receptor and modulates its down stream signaling. Here we have shown that CXCR4 expression prevents beta-adrenergic receptor induced hypertrophy. Cardiac beta-adrenergic receptors were stimulated with the implantation of a subcutaneous osmotic pump administrating isoproterenol and CXCR4 expression was selectively abrogated in cardiomyocytes using Cre-loxP-mediated gene recombination. CXCR4 knockout mice showed worsened fractional shortening and ejection fraction. CXCR4 ablation increased susceptibility to isoproterenol-induced heart failure, by upregulating apoptotic markers and reducing mitochondrial function; cardiac function decreases while fibrosis increases. Additionally, CXCR4 expression was rescued with the use of cardiotropic Adeno-associated viral-9 (AAV9) vectors. CXCR4 gene transfer reduced cardiac apoptotic signaling, improved mitochondrial function and resulted in a recovered cardiac function. Our results represent the first evidence that SDF-1/CXCR4 signaling mediates acute cardioprotection through modulating beta-adrenergic receptor signaling in vivo. PMID:24646609

The modulation of apoptosis by oncogenic viruses

PubMed Central

2013-01-01

Transforming viruses can change a normal cell into a cancer cell during their normal life cycle. Persistent infections with these viruses have been recognized to cause some types of cancer. These viruses have been implicated in the modulation of various biological processes, such as proliferation, differentiation and apoptosis. The study of infections caused by oncogenic viruses had helped in our understanding of several mechanisms that regulate cell growth, as well as the molecular alterations leading to cancer. Therefore, transforming viruses provide models of study that have enabled the advances in cancer research. Viruses with transforming abilities, include different members of the Human Papillomavirus (HPV) family, Hepatitis C virus (HCV), Human T-cell Leukemia virus (HTLV-1), Epstein Barr virus (EBV) and Kaposi’s Sarcoma Herpesvirus (KSHV). Apoptosis, or programmed cell death, is a tightly regulated process that plays an important role in development and homeostasis. Additionally, it functions as an antiviral defense mechanism. The deregulation of apoptosis has been implicated in the etiology of diverse diseases, including cancer. Oncogenic viruses employ different mechanisms to inhibit the apoptotic process, allowing the propagation of infected and damaged cells. During this process, some viral proteins are able to evade the immune system, while others can directly interact with the caspases involved in apoptotic signaling. In some instances, viral proteins can also promote apoptosis, which may be necessary for an accurate regulation of the initial stages of infection. PMID:23741982

Coxiella burnetii Employs the Dot/Icm Type IV Secretion System to Modulate Host NF-κB/RelA Activation

PubMed Central

Mahapatra, Saugata; Gallaher, Brandi; Smith, Sydni Caet; Graham, Joseph G.; Voth, Daniel E.; Shaw, Edward I.

2016-01-01

Coxiella burnetii is the causative agent of Q fever and an obligate intracellular pathogen in nature that survives and grows in a parasitophorous vacuole (PV) within eukaryotic host cells. C. burnetii promotes intracellular survival by subverting apoptotic and pro-inflammatory signaling pathways that are typically regulated by nuclear transcription factor-κB (NF-κB). We and others have demonstrated that C. burnetii NMII proteins inhibit expression of pro-inflammatory cytokines and induce expression of anti-apoptotic genes during infection. Here, we demonstrate that C. burnetii promotes intracellular survival by modulating NF-κB subunit p65 (RelA) phosphorylation, and thus activation, in a Type Four B Secretion System (T4BSS)-dependent manner. Immunoblot analysis of RelA phosphorylated at serine-536 demonstrated that C. burnetii increases NF-κB activation via the canonical pathway. However, RelA phosphorylation levels were even higher in infected cells where bacterial protein or mRNA synthesis was inhibited. Importantly, we demonstrate that inhibition of RelA phosphorylation impairs PV formation and C. burnetii growth. We found that a T4BSS-defective mutant (CbΔdotA) elicited phosphorylated RelA levels similar to those of wild type C. burnetii infection treated with Chloramphenicol. Moreover, cells infected with CbΔdotA or wild type C. burnetii treated with Chloramphenicol showed similar levels of GFP-RelA nuclear localization, and significantly increased localization compared to wild type C. burnetii infection. These data indicate that without de novo protein synthesis and a functional T4BSS, C. burnetii is unable to modulate NF-κB activation, which is crucial for optimal intracellular growth. PMID:28066723

Role of extracellular matrix in regulation of staurosporine-induced apoptosis in breast cancer cells.

PubMed

Vasaturo, F; Malacrino, C; Sallusti, E; Coppotelli, G; Birarelli, P; Giuffrida, A; Albonici, L; Simonelli, L; Modesti, A; Modesti, M; Scarpa, S

2005-04-01

Autocrine and paracrine mechanisms modulate the synthesis and secretion of extracellular matrix (ECM); moreover, each component of the ECM is capable of modulating the synthesis and release of other ECM molecules. Therefore, the synthesis of ECM glycoprotein fibronectin and laminin was studied in the human breast cancer cell lines MCF7 and MDA MB 23, plated on different ECM. Our results showed that the cells plated on a fibronectin substrate increased laminin synthesis: this event correlated with an increase in alpha2 and alpha3 integrin subunits. Staurosporine-induced apoptosis was then analyzed in the cell lines plated on different ECM. Staurosporine treatment determined the apoptosis of 35 and 33% respectively of MDA MB 231 and MCF7; these values increased to 60 and 64% in cells plated on laminin, to 48 and 63% in cells plated on fibronectin and to 64 and 69% in cells plated on matrigel. Moreover, staurosporine treatment decreased bcl-2 expression in the cells plated on fibronectin and laminin. Yet, staurosporine treatment determined PARP cleavage and PARP partial disappearance when the cells were plated on matrigel. Finally, a partial loss of function mutant Ras protein that activated only Raf pathway, was expressed in MCF7, in order to identify whether the increase of apoptosis induced by extracellular matrix involved the Raf/MAP kinase pathway. The increase of apoptosis of the cells plated on matrigel suggested that the activation of the Raf pathway is probably involved in the decrease of survival on matrigel. These data demonstrate that the modification of ECM modulates the apoptotic process of breast cancer cells and suggest that it is worthwhile to dissect the role of ECM in the control of apoptotic process.

Alteration in apoptotic rate of testicular cells and sperms following administration of Bisphenol A (BPA) in Wistar albino rats.

PubMed

Srivastava, Seema; Gupta, Priya

2018-05-21

The aim of the study was to evaluate the effect of Bisphenol A [BPA] widely used as a plasticizer in the formation of polycarbonate plastics and epoxy resins, exposure causing alteration in apoptosis rate, and protective effect of Vitamin E when supplemented with BPA orally. Adult male Wistar albino rats aged 3 months were randomly divided into seven groups: control (olive oil treated) BPA-treated (dose 5, 50,100 μg/100gmBW) and Vitamin E intervention group (dose 5, 50, 100 μg/100gmBW BPA+ Vitamin E dose 4 mg/100gmBW). Animals were sacrificed 3 months later, and blood and tissue samples were collected. Apoptotic changes were analyzed in epididymal spermatozoa and testis tissue by binding of annexin V apoptotic biomarker. A significant decline in the weight of testis, testosterone level, and sperm count was observed. Histopathological and apoptotic changes were observed in testis tissue. In epididymal sperms, the early apoptotic cells were observed by staining of annexin V-conjugated FITC and PI green fluorescence in spermatozoa head which indicated the damage of membrane and late apoptotic cells. These changes reduced significantly in Vitamin E-treated groups though were not found to be comparable to control animals. All these changes were attributed to disrupted spermatogenesis that would interfere with sperm formation. Thus, the study infers that BPA affects the apoptosis process in the testis and epididymal sperm that would interfere with its function and contribute to infertility, whereas Vitamin E-supplemented dose has a protective effect towards these changes, indicating its role in improving male fertility.

Tetramethylpyrazine analogue CXC195 protects against cerebral ischemia/reperfusion-induced apoptosis through PI3K/Akt/GSK3β pathway in rats.

PubMed

Chen, Lin; Wei, Xinbing; Hou, Yunfeng; Liu, Xiaoqian; Li, Senpeng; Sun, Baozhu; Liu, Xinyong; Liu, Huiqing

2014-01-01

CXC195 showed strongest protective effects among the ligustrazine derivatives in cells and prevented apoptosis induced by H2O2 injury. We recently demonstrated that CXC195 protected against cerebral ischemia/reperfusion (I/R) injury by its antioxidant activity. However, whether the anti-apoptotic action of CXC195 is involved in cerebral I/R injury is unknown. Here, we investigated the role of CXC195 in apoptotic processes induced by cerebral I/R and the possible signaling pathways. Male Wistar rats were submitted to transient middle cerebral artery occlusion for 2h, followed by 24h reperfusion. CXC195 was injected intraperitoneally at 2h and 12h after the onset of ischemia. The number of apoptotic cells was measured by TUNEL assay, apoptosis-related protein cleaved caspase-3, Bcl-2, Bax and the phosphorylation levels of Akt and GSK3β in ischemic penumbra were assayed by western blot. The results showed that administration of CXC195 at the doses of 3mg/kg and 10mg/kg significantly inhibited the apoptosis by decreasing the number of apoptotic cells, decreasing the level of cleaved caspase-3 and Bax, and increasing the level of Bcl-2 in rats subjected to I/R injury. Simultaneously, CXC195 treatment markedly increased the phosphorylation of Akt and GSK3β. Blockade of PI3K activity by wortmannin, dramatically abolished its anti-apoptotic effect and lowered both Akt and GSK3β phosphorylation levels. Our study firstly demonstrated that CXC195 protected against cerebral I/R injury by reducing apoptosis in vivo and PI3K/Akt/GSK3β pathway involved in the anti-apoptotic effect. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Minocycline exacerbates apoptotic neurodegeneration induced by the NMDA receptor antagonist MK-801 in the early postnatal mouse brain.

PubMed

Inta, Ioana; Vogt, Miriam A; Vogel, Anne S; Bettendorf, Markus; Gass, Peter; Inta, Dragos

2016-10-01

NMDA receptor (NMDAR) antagonists induce in perinatal rodent cortical apoptosis and protracted schizophrenia-like alterations ameliorated by antipsychotic treatment. The broad-spectrum antibiotic minocycline elicits antipsychotic and neuroprotective effects. Here we tested, if minocycline protects also against apoptosis triggered by the NMDAR antagonist MK-801 at postnatal day 7. Surprisingly, minocycline induced widespread cortical apoptosis and exacerbated MK-801-triggered cell death. In some areas such as the subiculum, the pro-apoptotic effect of minocycline was even more pronounced than that elicited by MK-801. These data reveal among antipsychotics unique pro-apoptotic properties of minocycline, raising concerns regarding consequences for brain development and the use in children.

Neuroprotective and anti-apoptotic propensity of Bacopa monniera extract against sodium nitroprusside induced activation of iNOS, heat shock proteins and apoptotic markers in PC12 cells.

PubMed

Pandareesh, M D; Anand, T

2014-05-01

Sodium nitroprusside (SNP) is a widely used nitric oxide (NO) donor, known to exert nitrative stress by up-regulation of inducible nitric oxide synthase (iNOS). Nω-nitro-L-arginine-methyl esther (L-NAME) is a NO inhibitor, which inhibits iNOS expression, is used as positive control. The present study was designed to assess neuroprotective propensity of Bacopa monniera extract (BME) in SNP-induced neuronal damage and oxido-nitrative stress in PC12 cells via modulation of iNOS, heat shock proteins and apoptotic markers. Our results elucidate that pre-treatment of PC12 cells with BME ameliorates the mitochondrial and plasma membrane damage induced by SNP (200 μM) as evidenced by MTT and LDH assays. BME pre-treatment inhibited NO generation by down regulating iNOS expression. BME replenished the depleted antioxidant status induced by SNP treatment. SNP-induced damage to cellular, nuclear and mitochondrial integrity was also restored by BME, which was confirmed by ROS estimation, comet assay and mitochondrial membrane potential assays respectively. BME pre-treatment efficiently attenuated the SNP-induced apoptotic protein biomarkers such as Bax, Bcl-2, cytochrome-c and caspase-3, which orchestrate the proteolytic damage of the cell. Q-PCR results further elucidated up-regulation of neuronal cell stress markers like HO-1 and iNOS and down-regulation of BDNF upon SNP exposure was attenuated by BME pre-treatment. By considering all these findings, we report that BME protects PC12 cells against SNP-induced toxicity via its free radical scavenging and neuroprotective mechanism.

Role of the urokinase plasminogen activator receptor in mediating impaired efferocytosis of anti-SSA/Ro-bound apoptotic cardiocytes: Implications in the pathogenesis of congenital heart block.

PubMed

Briassouli, Paraskevi; Komissarova, Elena V; Clancy, Robert M; Buyon, Jill P

2010-08-06

Binding of maternal anti-Ro/La antibodies to cognate antigen expressed on apoptotic cardiocytes decreases clearance by healthy cardiocytes, which may contribute to the development of autoimmune associated congenital heart block and fatal cardiomyopathy. Given recent evidence implicating the urokinase plasminogen activator receptor (uPAR) as a "don't eat me" signal during efferocytosis, experiments addressed whether surface bound anti-Ro antibodies inhibit apoptotic cell removal via an effect on the expression/function of the urokinase-type plasminogen activator protease uPA/uPAR system. As assessed by flow cytometry and confocal microscopy, uPAR colocalizes and interacts with Ro60 on the surface of apoptotic human fetal cardiocytes. Blocking of uPAR enhances phagocytosis of apoptotic cardiocytes by healthy cardiocytes and reverses the anti-Ro60-dependent impaired clearance of apoptotic cardiocytes. Binding of anti-Ro60 antibodies to apoptotic cardiocytes results in increased uPAR expression, as well as enhanced uPA activity. The binding of anti-Ro60 did not alter other surface molecules involved in cell recognition (calreticulin, CD31, or CD47). These data suggest that increased uPAR expression and uPA activity induced by anti-Ro60 binding to the apoptotic fetal cardiocyte provide a molecular basis by which these antibodies inhibit efferocytosis and ultimately lead to scar of the fetal conduction system and working myocardium.

ApoE gene deficiency enhances the reduction of bone formation induced by a high-fat diet through the stimulation of p53-mediated apoptosis in osteoblastic cells.

PubMed

Hirasawa, Hideyuki; Tanaka, Shinya; Sakai, Akinori; Tsutsui, Masato; Shimokawa, Hiroaki; Miyata, Hironori; Moriwaki, Sawako; Niida, Shumpei; Ito, Masako; Nakamura, Toshitaka

2007-07-01

Osteoblast apoptosis increased in the tibias of apoE(-/-) mice fed with a high-fat diet, decreasing bone formation. The expression of p53 mRNA in marrow adherent cells increased. LDL or oxidized LDL increased apoptosis in the calvarial cells of apoE(-/-) mice. The increase in p53-mediated apoptosis is apparently related to a high-fat diet-induced osteopenia in apoE(-/-) mice. The effects of high-fat loading and the apolipoprotein E (apoE) gene on bones have not been elucidated. We hypothesized that apoE gene deficiency (apoE(-/-)) modulates the effects of high-fat loading on bones. We assessed this hypothesis using wildtype (WT) and apoE(-/-) mice fed a standard (WTS and ApoES groups) or a high-fat diet (WTHf and ApoEHf groups). The concentration of serum lipid levels and bone chemical markers were measured. Histomorphometry of the femurs was performed using microCT and a microscope. Bone marrow adherent cells from the femurs were used for colony-forming unit (CFU)-fibroblastic (CFU-f) assay and mRNA expressions analysis. The apoptotic cells in the tibias were counted. TUNEL fluorescein assay and Western analysis were performed in cultures of calvarial cells by the addition of low-density lipoprotein (LDL) or oxidized LDL. In the ApoEHf group, the values of cortical bone volume and trabecular and endocortical bone formation of the femurs decreased, and urinary deoxypyridinoline increased. Subsequent analysis revealed that the number of apoptotic cells in the tibias of the ApoES group increased, and more so in the ApoEHf group. The ratio of alkaline phosphatase-positive CFU-f to total CFU-f was decreased in the ApoEHf group. p53 mRNA expression in adherent cells of the apoE(-/-) mice increased and had a significantly strong positive correlation with serum LDL. TUNEL fluorescein assay of osteoblastic cells revealed an increase of apoptotic cells in the apoE(-/-) mice. The number of apoptotic cells in the apoE(-/-) mice increased with the addition of 100 microg/ml LDL or oxidized LDL. The p53 protein expression in apoE(-/-) cells exposed to 100 microg/ml LDL or oxidized LDL increased. We concluded that apoE gene deficiency enhances the reduction of bone formation induced by a high-fat diet through the stimulation of p53-mediated apoptosis in osteoblastic cells.

Caspase-mediated pro-apoptotic interaction of panaxadiol and irinotecan in human colorectal cancer cells.

PubMed

Du, Guang-Jian; Wang, Chong-Zhi; Zhang, Zhi-Yu; Wen, Xiao-Dong; Somogyi, Jacqueline; Calway, Tyler; He, Tong-Chuan; Du, Wei; Yuan, Chun-Su

2012-05-01

Panaxadiol is a purified sapogenin of ginseng saponins that exhibits anticancer activity. Irinotecan is a second-line anticancer drug, but clinical treatment with irinotecan is limited due to its side effects. In this study, we have investigated the possible synergistic anticancer effects of panaxadiol and irinotecan on human colorectal cancer cells and explored the potential role of apoptosis in their synergistic activity. The combination of panaxadiol and irinotecan significantly enhanced antiproliferative effects in HCT-116 cells (P< 0.05). Cell cycle analysis demonstrated that combining irinotecan treatment with panaxadiol significantly increased the G1-phase fractions of cells, compared with irinotecan treatment alone. In apoptotic assays, the combination of panaxadiol and irinotecan significantly increased the percentage of apoptotic cells compared with irinotecan alone (P<0.01). Increased activity of caspase-3 and caspase-9 was observed after treating with panaxadiol and irinotecan. The synergistic apoptotic effects were supported by docking analysis, which demonstrated that panaxadiol and irinotecan bound two different chains of the caspase-3 protein. Data from this study suggested that caspase-3- and caspase-9-mediated apoptosis may play an important role in the panaxadiol enhanced antiproliferative effects of irinotecan on human colorectal cancer cells. © 2012 The Authors. JPP © 2012 Royal Pharmaceutical Society.

Tauroursodeoxycholic acid increases neural stem cell pool and neuronal conversion by regulating mitochondria-cell cycle retrograde signaling

PubMed Central

Xavier, Joana M; Morgado, Ana L; Rodrigues, Cecília MP; Solá, Susana

2014-01-01

The low survival and differentiation rates of stem cells after either transplantation or neural injury have been a major concern of stem cell-based therapy. Thus, further understanding long-term survival and differentiation of stem cells may uncover new targets for discovery and development of novel therapeutic approaches. We have previously described the impact of mitochondrial apoptosis-related events in modulating neural stem cell (NSC) fate. In addition, the endogenous bile acid, tauroursodeoxycholic acid (TUDCA) was shown to be neuroprotective in several animal models of neurodegenerative disorders by acting as an anti-apoptotic and anti-oxidant molecule at the mitochondrial level. Here, we hypothesize that TUDCA might also play a role on NSC fate decision. We found that TUDCA prevents mitochondrial apoptotic events typical of early-stage mouse NSC differentiation, preserves mitochondrial integrity and function, while enhancing self-renewal potential and accelerating cell cycle exit of NSCs. Interestingly, TUDCA prevention of mitochondrial alterations interfered with NSC differentiation potential by favoring neuronal rather than astroglial conversion. Finally, inhibition of mitochondrial reactive oxygen species (mtROS) scavenger and adenosine triphosphate (ATP) synthase revealed that the effect of TUDCA is dependent on mtROS and ATP regulation levels. Collectively, these data underline the importance of mitochondrial stress control of NSC fate decision and support a new role for TUDCA in this process. PMID:25483094

Selenium attenuates apoptosis, inflammation and oxidative stress in the blood and brain of aged rats with scopolamine-induced dementia.

PubMed

Demirci, Kadir; Nazıroğlu, Mustafa; Övey, İshak Suat; Balaban, Hasan

2017-04-01

A potent antioxidant, selenium might modulate dementia-induced progression of brain and blood oxidative and apoptotic injuries. The present study explores whether selenium protects against experimental dementia (scopolamine, SCOP)-induced brain, and blood oxidative stress, apoptosis levels, and cytokine production in rats. Thirty-two rats were equally divided into four groups. The first group was used as an untreated control. The second group was treated with SCOP to induce dementia. The third and fourth groups received 1.5 mg/kg selenium (sodium selenite) and SCOP + selenium, respectively. Dementia was induced in the second and forth groups by intraperitoneal SCOP (1 mg/kg) administration. Brain, plasma, and erythrocyte lipid peroxidation levels as well as plasma TNF-α, interleukin (IL)-1β, and IL-4 levels were high in the SCOP group though they were low in selenium treatments. Selenium and selenium + SCOP treatments increased the lowered glutathione peroxidase activity, reduced glutathione, vitamins A and E concentrations in the brain, erythrocytes and plasma of the SCOP group. Apoptotic value expressions as active caspase-3, procaspase-9, and PARP were also increased by SCOP, while they were decreased by selenium and selenium + SCOP treatments. In conclusion, selenium induced protective effects against experimental dementia-induced brain, and blood oxidative injuries and apoptosis through regulation of cytokine production, vitamin E, glutathione concentrations, and glutathione peroxidase activity.

Spermine reduces reactive oxygen species levels and decreases cryocapacitation in canine sperm cryopreservation.

PubMed

Setyawan, Erif Maha Nugraha; Kim, Min Jung; Oh, Hyun Ju; Kim, Geon A; Jo, Young Kwang; Lee, Seok Hee; Choi, Yoo Bin; Lee, Byeong Chun

2016-10-28

The objective of this study was to determine the ability of spermine to act as an antioxidant in scavenging reactive oxygen species (ROS), maintaining sperm function and decreasing cryocapacitation after cryopreservation. Although motility did not increase with spermine treatment, values for membrane integrity were significantly increased (P < 0.05). Higher percentages of linearity and straightness with a lower amplitude of lateral head displacement (ALH) indicated that spermine inhibits hyperactivation. Concentrations of intracellular and extracellular ROS were decreased in the treatment group (P < 0.05). Higher expression of an anti-apoptotic gene (Bcl-2) and lower expression of a pro-apoptotic gene (Bax), together with decreased expression of the mitochondrial ROS modulator ROMO1, DNA repair due to oxidative damage (OGG1), spermine synthase (SMS), NADPH oxidase associated with motility (NOX5) and spermine amino oxidase (SMOX), all showed that 5.0 mM spermine treatment was beneficial to spermatozoa. Furthermore, the proportion of live spermatozoa with intact acrosomes after thawing in the treatment group was higher than in the control. After incubation in canine capacitating medium, numbers of live capacitated spermatozoa with reacted acrosomes were higher than in the control. Our results indicate that 5.0 mM spermine is an optimal concentration for maintaining sperm function, reducing ROS production, preventing apoptosis and adverse effects of cryocapacitation during canine sperm cryopreservation. Copyright © 2016 Elsevier Inc. All rights reserved.

Tunicamycin promotes apoptosis in leukemia cells through ROS generation and downregulation of survivin expression.

PubMed

Lim, Eun Jin; Heo, Jeonghoon; Kim, Young-Ho

2015-08-01

Tunicamycin (TN), one of the endoplasmic reticulum stress inducers, has been reported to inhibit tumor cell growth and exhibit anticarcinogenic activity. However, the mechanism by which TN initiates apoptosis remains poorly understood. In the present study, we investigated the effect of TN on the apoptotic pathway in U937 cells. We show that TN induces apoptosis in association with caspase-3 activation, generation of reactive oxygen species (ROS), and downregulation of survivin expression. P38 MAPK (mitogen-activated protein kinase) and the generation of ROS signaling pathway play crucial roles in TN-induced apoptosis in U937 cells. We hypothesized that TN-induced activation of p38 MAPK signaling pathway is responsible for cell death. To test this hypothesis, we selectively inhibited MAPK during treatment with TN. Our data demonstrated that inhibitor of p38 (SB), but not ERK (PD) or JNK (SP), partially maintained apoptosis during treatment with TN. Pre-treatment with NAC and GSH markedly prevented cell death, suggesting a role for ROS in this process. Ectopic expression of survivin in U937 cells attenuated TN-induced apoptosis by suppression of caspase-3 cleavage, mitochondrial membrane potential, and cytochrome c release in U937 cells. Taken together, our results show that TN modulates multiple components of the apoptotic response of human leukemia cells and raise the possibility of a novel therapeutic strategy for hematological malignancies.

The Tuberin/mTOR Pathway Promotes Apoptosis of Tubular Epithelial Cells in Diabetes

PubMed Central

Velagapudi, Chakradhar; Bhandari, Basant S.; Abboud-Werner, Sherry; Simone, Simona; Abboud, Hanna E.

2011-01-01

Apoptosis contributes to the development of diabetic nephropathy, but the mechanism by which high glucose (HG) induces apoptosis is not fully understood. Because the tuberin/mTOR pathway can modulate apoptosis, we studied the role of this pathway in apoptosis in type I diabetes and in cultured proximal tubular epithelial (PTE) cells exposed to HG. Compared with control rats, diabetic rats had more apoptotic cells in the kidney cortex. Induction of diabetes also increased phosphorylation of tuberin in association with mTOR activation (measured by p70S6K phosphorylation), inactivation of Bcl-2, increased cytosolic cytochrome c expression, activation of caspase 3, and cleavage of PARP; insulin treatment prevented these changes. In vitro, exposure of PTE cells to HG increased phosphorylation of tuberin and p70S6K, phosphorylation of Bcl-2, expression of cytosolic cytochrome c, and caspase 3 activity. High glucose induced translocation of the caspase substrate YY1 from the cytoplasm to the nucleus and enhanced cleavage of PARP. Pretreatment the cells with the mTOR inhibitor rapamycin reduced the number of apoptotic cells induced by HG and the downstream effects of mTOR activation noted above. Furthermore, gene silencing of tuberin with siRNA decreased cleavage of PARP. These data show that the tuberin/mTOR pathway promotes apoptosis of tubular epithelial cells in diabetes, mediated in part by cleavage of PARP by YY1. PMID:21289215

Methylglyoxal causes strong weakening of detoxifying capacity and apoptotic cell death in rat hippocampal neurons.

PubMed

Di Loreto, Silvia; Zimmitti, Vincenzo; Sebastiani, Pierluigi; Cervelli, Carla; Falone, Stefano; Amicarelli, Fernanda

2008-01-01

The hippocampus is known to play a crucial role in learning and memory. Recent data from literature show that cognitive problems, common to aged or diabetic patients, may be related to accumulation of toxic alpha-oxoaldehydes such as methylglyoxal. Thus, it is possible that methylglyoxal could be, at least in part, responsible for the impairment of cognitive functions, and the knowledge of the mechanisms through which this compound elicits neuronal toxicity could be useful for the development of possible therapeutic strategies. We previously reported a high susceptibility of hippocampal neurons to methylglyoxal, through an oxidation-dependent mechanism. In the present study, we extend our investigation on the molecular mechanisms which underlie methylglyoxal toxicity, focusing on possible effects on expression and activity of glyoxalases, its main detoxifying enzymes, and glutathione peroxidase, as well as on the levels of reduced glutathione. We also investigate methylglyoxal-induced modulation of brain derived neurotrophic factor and proinflammatory cytokines. Our results show that methylglyoxal causes a dramatic depletion of reduced glutathione and a significant inhibition of both glyoxalase and glutathione peroxidase activities. Furthermore, methylglyoxal treatment seems to affect the expression of inflammatory cytokines and survival factors. In conclusion, our findings suggest that methylglyoxal-induced neurotoxicity occurs through the impairment of detoxification pathway and depletion of reduced glutathione. This, in turn, triggers widespread apoptotic cell death, occurring through the convergence of both mitochondrial and Fas-receptor pathways.

Effect of mitochondrial apoptotic activation through the mitochondrial membrane permeability transition pore on yak meat tenderness during postmortem aging.

PubMed

Wang, Lin-Lin; Han, Ling; Ma, Xiu-Li; Yu, Qun-Li; Zhao, Suo-Nan

2017-11-01

The effect of membrane permeability transition pore dependent mitochondrial apoptotic activation on yak meat tenderness was investigated. Results indicate that MPTP opening increased significantly and the mitochondrial membrane potential decreased markedly in the early aging process (P<0.05). Cytochrome c was released from the mitochondria to the cytoplasm via the MPTP in the early period. Meanwhile, the activation of procaspase-9 occurred earlier than that of procaspase-3. Cyclosporin A suppressed the MPTP opening, depolarization of the mitochondrial membrane potential, activities of caspase-9 and caspase-3, apoptosis rate, myofibril fragmentation index, reactive oxygen species generation, and Ca 2+ levels. These results demonstrated that MPTP mediated the release of cytochrome c in the mitochondrial apoptotic pathway. Furthermore, yak meat tenderness was improved by mitochondrial apoptotic pathway during aging. MPTP opening may be influenced by the ROS generation and Ca 2+ overloading in yak meat during postmortem aging. Copyright © 2017 Elsevier Ltd. All rights reserved.

Garcinol Upregulates GABAA and GAD65 Expression, Modulates BDNF-TrkB Pathway to Reduce Seizures in Pentylenetetrazole (PTZ)-Induced Epilepsy

PubMed Central

Hao, Fang; Jia, Li-Hua; Li, Xiao-Wan; Zhang, Ying-Rui; Liu, Xue-Wu

2016-01-01

Background Epilepsy is the most predominant neurological disorder characterized by recurrent seizures. Despite treatment with antiepileptic drugs, epilepsy still is a challenge to treat, due to the associated adverse effects of the drugs. Previous investigations have shown critical roles of BDNF-TrkB signalling and expression of glutamic acid decarboxylase 65 (GAD65) and GABAA in the brain during epilepsy. Thus, drugs that could modulate BDNF-TrkB signal and expression of GAD65 and GABAA could aid in therapy. Recent experimental data have focussed on plant-derived compounds in treatments. Garcinol (camboginol), is a polyisoprenylated benzophenone derived from the fruit of Garcinia indica. We investigated the effects of garcinol in pentylenetetrazole (PTZ)-induced epileptic models. Material/Methods Seizure scores were measured in epilepsy kindled mice. Neuronal degeneration and apoptosis were assessed by Nissl staining, TUNEL assay, and Fluoro-Jade B staining. Immunohistochemistry was performed to evaluate cleaved caspase-3 expressions. Expression of BDNF, TrkB, GABAA, GAD65, Bad, Bcl-2, Bcl-xL, and Bax were determined by western blots. Results Significantly reduced seizure scores and mortality rates were observed with pretreatment with garcinol. Elevated expression of apoptotic proteins and caspase-3 in kindled mice were effectively downregulated by garcinol. Epileptogenic mice presented increased BDNF and TrkB with considerably decreased GABAA and GAD65 expression. Garcinol significantly enhanced GABAA and GAD65 while it suppressed BDNF and TrkB. Garcinol enhanced the performance of mice in Morris water maze tests. Conclusions Garcinol exerts neuroprotective effects via supressing apoptosis and modulating BDNF-TrkB signalling and GAD65/GABAA expressions and also enhanced cognition and memory of the mice. PMID:27855137

Targeting ceramide metabolic pathway induces apoptosis in human breast cancer cell lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vethakanraj, Helen Shiphrah; Babu, Thabraz Ahmed; Sudarsanan, Ganesh Babu

2015-08-28

The sphingolipid ceramide is a pro apoptotic molecule of ceramide metabolic pathway and is hydrolyzed to proliferative metabolite, sphingosine 1 phosphate by the action of acid ceramidase. Being upregulated in the tumors of breast, acid ceramidase acts as a potential target for breast cancer therapy. We aimed at targeting this enzyme with a small molecule acid ceramidase inhibitor, Ceranib 2 in human breast cancer cell lines MCF 7 and MDA MB 231. Ceranib 2 effectively inhibited the growth of both the cell lines in dose and time dependant manner. Morphological apoptotic hallmarks such as chromatin condensation, fragmented chromatin were observedmore » in AO/EtBr staining. Moreover, ladder pattern of fragmented DNA observed in DNA gel electrophoresis proved the apoptotic activity of Ceranib 2 in breast cancer cell lines. The apoptotic events were associated with significant increase in the expression of pro-apoptotic genes (Bad, Bax and Bid) and down regulation of anti-apoptotic gene (Bcl 2). Interestingly, increase in sub G1 population of cell cycle phase analysis and elevated Annexin V positive cells after Ceranib 2 treatment substantiated its apoptotic activity in MCF 7 and MDA MB 231 cell lines. Thus, we report Ceranib 2 as a potent therapeutic agent against both ER{sup +} and ER{sup −} breast cancer cell lines. - Highlights: • Acid Ceramidase inhibitor, Ceranib 2 induced apoptosis in Breast cancer cell lines (MCF 7 and MDA MB 231 cell lines). • Apoptosis is mediated by DNA fragmentation and cell cycle arrest. • Ceranib 2 upregulated the expression of pro-apoptotic genes and down regulated anti-apoptotic gene expression. • More potent compared to the standard drug Tamoxifen.« less

Neuroprotective effects of corn silk maysin via inhibition of H2O2-induced apoptotic cell death in SK-N-MC cells.

PubMed

Choi, Doo Jin; Kim, Sun-Lim; Choi, Ji Won; Park, Yong Il

2014-07-25

Neuroprotective effects of maysin, which is a flavone glycoside that was isolated from the corn silk (CS, Zea mays L.) of a Korean hybrid corn Kwangpyeongok, against oxidative stress (H2O2)-induced apoptotic cell death of human neuroblastoma SK-N-MC cells were investigated. Maysin cytotoxicity was determined by measuring cell viability using MTT and lactate dehydrogenase (LDH) assays. Intracellular reactive oxygen species (ROS) were measured using a 2,7-dichlorofluorescein diacetate (DCF-DA) assay. Apoptotic cell death was monitored by annexin V-FITC/PI double staining and by a TUNEL assay. Antioxidant enzyme mRNA levels were determined by real-time PCR. The cleavage of poly (ADP-ribose) polymerase (PARP) was measured by western blotting. Maysin pretreatment reduced the cytotoxic effect of H2O2 on SK-N-MC cells, as shown by the increase in cell viability and by reduced LDH release. Maysin pretreatment also dose-dependently reduced the intracellular ROS level and inhibited PARP cleavage. In addition, DNA damage and H2O2-induced apoptotic cell death were significantly attenuated by maysin pretreatment. Moreover, maysin pretreatment (5-50 μg/ml) for 2h significantly and dose-dependently increased the mRNA levels of antioxidant enzymes (CAT, GPx-1, SOD-1, SOD-2 and HO-1) in H2O2 (200 μM)-insulted cells. These results suggest that CS maysin has neuroprotective effects against oxidative stress (H2O2)-induced apoptotic death of human brain SK-N-MC cells through its antioxidative action. This report is the first regarding neuroprotective health benefits of corn silk maysin by its anti-apoptotic action and by triggering the expression of intracellular antioxidant enzyme systems in SK-N-MC cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Expression and proliferation profiles of PKC, JNK and p38MAPK in physiologically stretched human bladder smooth muscle cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wazir, Romel; Luo, De-Yi; Dai, Yi

2013-08-30

Highlights: •Stretch induces proliferation in human bladder smooth muscle cells (HBSMC). •5% Equibiaxial elongation produces maximum proliferation. •Physiologic stretch decreases apoptotic cell death. •PKC is involved in functional modulation of bladder. •JNK and p38 are not involved in proliferating HBSMC. -- Abstract: Objective: To determine protein kinase C (PKC), c-Jun NH2-Terminal Kinase (JNK) and P38 mitogen-activated protein kinases (p38MAPK) expression levels and effects of their respective inhibitors on proliferation of human bladder smooth muscle cells (HBSMCs) when physiologically stretched in vitro. Materials and methods: HBSMCs were grown on silicone membrane and stretch was applied under varying conditions; (equibiaxial elongation: 2.5%,more » 5%, 10%, 15%, 20%, 25%), (frequency: 0.05, 0.1, 0.2, 0.5, 1 Hz). Optimal physiological stretch was established by assessing proliferation with 5-Bromo-2-deoxyuridine (BrdU) assay and flow cytometry. PKC, JNK and p38 expression levels were analyzed by Western blot. Specificity was maintained by employing specific inhibitors; (GF109203X for PKC, SP600125 for JNK and SB203580 for p38MAPK), in some experiments. Results: Optimum proliferation was observed at 5% equibiaxial stretch (BrdU: 0.837 ± 0.026 (control) to 1.462 ± 0.023)%, (P < 0.05) and apoptotic cell death rate decreased from 16.4 ± 0.21% (control) to 4.5 ± 0.13% (P < 0.05) applied at 0.1 Hz. Expression of PKC was upregulated with slight increase in JNK and no change in p38MAPK after application of stretch. Inhibition had effects on proliferation (1.075 ± 0.024, P < 0.05 GF109203X); (1.418 ± 0.021, P > 0.05 SP600125) and (1.461 ± 0.01, P > 0.05 SB203580). These findings show that mechanical stretch can promote magnitude-dependent proliferative modulation through PKC and possibly JNK but not via p38MAPK in hBSMCs.« less

Repeated Exposure of Epithelial Cells to Apoptotic Cells Induces the Specific Selection of an Adaptive Phenotype: Implications for Tumorigenesis.

PubMed

Feng, Lanfei; Vujicic, Snezana; Dietrich, Michael E; Litbarg, Natalia; Setty, Suman; Antoni, Angelika; Rauch, Joyce; Levine, Jerrold S

2018-05-16

The consequences of apoptosis extend beyond mere death of the cell. We have shown that receptor-mediated recognition of apoptotic target cells by viable kidney proximal tubular epithelial cells (PTECs) inhibits PTEC proliferation, growth, and survival. Here we tested the hypothesis that continual exposure to apoptotic targets can induce a phenotypic change in responding PTECs, as in other instances of natural selection. In particular, we demonstrate that repeated exposure to apoptotic targets leads to emergence of a PTEC line (denoted BU.MPT SEL ) resistant to apoptotic target-induced death. Resistance is exquisitely specific. Not only are BU.MPT SEL responders fully resistant to apoptotic target-induced death (~85% survival versus <10% survival of non-selected cells), but do so while retaining sensitivity to all other target-induced responses, including inhibition of proliferation and growth. Moreover, the resistance of BU.MPT SEL responders is specific to target-induced apoptosis, as apoptosis in response to other suicidal stimuli occurs normally. Comparison of the signaling events induced by apoptotic target exposure in selected versus non-selected responders indicated that the acquired resistance of BU.MPT SEL cells lies in a regulatory step affecting the generation of the pro-apoptotic protein, truncated BH3 interacting-domain death agonist (tBID), most likely at the level of BID cleavage by caspase-8. This specific adaptation has especial relevance for cancer, in which the prominence and persistence of cell death entail magnification of the post-mortem effects of apoptotic cells. Just as cancer cells acquire specific resistance to chemotherapeutic agents, we propose that cancer cells may also adapt to their ongoing exposure to apoptotic targets. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

Mangiferin Has an Additive Effect on the Apoptotic Properties of Hesperidin in Cyclopia sp. Tea Extracts

PubMed Central

Bartoszewski, Rafal; Hering, Anna; Marszałł, Marcin; Stefanowicz Hajduk, Justyna; Bartoszewska, Sylwia; Kapoor, Niren; Kochan, Kinga; Ochocka, Renata

2014-01-01

A variety of biological pro-health activities have been reported for mangiferin and hesperidin, two major phenolic compounds of Honeybush (Cyclopia sp.) tea extracts. Given their increasing popularity, there is a need for understanding the mechanisms underlying the biological effects of these compounds. In this study, we used real-time cytotoxicity cellular analysis of the Cyclopia sp. extracts on HeLa cells and found that the higher hesperidin content in non-fermented "green" extracts correlated with their higher cytotoxicity compared to the fermented extracts. We also found that mangiferin had a modulatory effect on the apoptotic effects of hesperidin. Quantitative PCR analysis of hesperidin-induced changes in apoptotic gene expression profile indicated that two death receptor pathway members, TRADD and TRAMP, were up regulated. The results of this study suggest that hesperidin mediates apoptosis in HeLa cells through extrinsic pathway for programmed cell death. PMID:24633329

Morin protects gastric mucosa from nonsteroidal anti-inflammatory drug, indomethacin induced inflammatory damage and apoptosis by modulating NF-κB pathway.

PubMed

Sinha, Krishnendu; Sadhukhan, Pritam; Saha, Sukanya; Pal, Pabitra Bikash; Sil, Parames C

2015-04-01

Deregulation in prostaglandin (PG) biosynthesis, severe oxidative stress, inflammation and apoptosis contribute to the pathogenesis of nonsteroidal anti-inflammatory drug (NSAID)-induced gastropathy. Unfortunately, most of the prescribed anti-ulcer drugs generate various side effects. In this scenario, we could consider morin as a safe herbal potential agent against IND-gastropathy and rationalize its action systematically. Rats were pretreated with morin for 30 min followed by IND (48 mgkg(-1)) administration for 4 h. The anti-ulcerogenic nature of morin was assessed by morphological and histological analysis. Its effects on the inflammatory (MPO, cytokines, adhesion molecules), ulcer-healing (COXs, PGE(2)), and signaling parameters (NF-κB and apoptotic signaling) were assessed by biochemical, RP-HPLC, immunoblots, IHC, RT-PCR, and ELISA at the time points of their maximal changes due to IND administration. IND induced NF-κB and apoptotic signaling in rat's gastric mucosa. These increased proinflammatory responses, but reduced the antioxidant enzymes and other protective factors. Morin reversed all the adverse effects to prevent IND-induced gastric ulceration in a PGE2 independent manner. Also, it did not affect the absorption and/or primary pharmacological activity of IND. The gastroprotective action of morin is primarily attributed to its potent antioxidant nature that also helps in controlling several IND-induced inflammatory responses. For the first time, the study reveals a mechanistic basis of morin mediated protective action against IND-induced gastropathy. As morin is a naturally abundant safe antioxidant, future detailed pharmacokinetic and pharmacodynamic studies are expected to establish it as a gastroprotective agent. Copyright © 2015 Elsevier B.V. All rights reserved.

Royal Jelly Modulates Oxidative Stress and Apoptosis in Liver and Kidneys of Rats Treated with Cisplatin

PubMed Central

Karadeniz, Ali; Simsek, Nejdet; Karakus, Emre; Yildirim, Serap; Kara, Adem; Can, Ismail; Kisa, Fikrullah; Emre, Habib; Turkeli, Mehmet

2011-01-01

Cisplatin (CDDP) is one of the most active cytotoxic agents in the treatment of cancer and has adverse side effects such as nephrotoxicity and hepatotoxicity. The present study was designed to determine the effects of royal jelly (RJ) against oxidative stress caused by CDDP injury of the kidneys and liver, by measuring tissue biochemical and antioxidant parameters and investigating apoptosis immunohistochemically. Twenty-four Sprague Dawley rats were divided into four groups, group C: control group received 0.9% saline; group CDDP: injected i.p. with cisplatin (CDDP, 7 mg kg−1 body weight i.p., single dose); group RJ: treated for 15 consecutive days by gavage with RJ (300 mg/kg/day); group RJ + CDDP: treated by gavage with RJ 15 days following a single injection of CDDP. Malondialdehyde (MDA) and glutathione (GSH) levels, glutathione S-transferase (GST), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) activities were determined in liver and kidney homogenates, and the liver and kidney were also histologically examined. RJ elicited a significant protective effect towards liver and kidney by decreasing the level of lipid peroxidation (MDA), elevating the level of GSH, and increasing the activities of GST, GSH-Px, and SOD. In the immunohistochemical examinations were observed significantly enhanced apoptotic cell numbers and degenerative changes by cisplatin, but these histological changes were lower in the liver and kidney tissues of RJ + CDDP group. Besides, treatment with RJ lead to an increase in antiapoptotic activity hepatocytes and tubular epithelium. In conclusion, RJ may be used in combination with cisplatin in chemotherapy to improve cisplatin-induced oxidative stress parameters and apoptotic activity. PMID:21904651

Myocardial Protective Effects of L-Carnitine on Ischemia-Reperfusion Injury in Patients With Rheumatic Valvular Heart Disease Undergoing Cardiac Surgery.

PubMed

Li, Ming; Xue, Li; Sun, Haifeng; Xu, Suochun

2016-12-01

The authors used L-carnitine as an ingredient in cardioplegic solution during valve replacement surgery to investigate the protective effect of L-carnitine on myocardial ischemia-reperfusion injury (MIRI) and its possible mechanism. Prospective, randomized study. A tertiary-care hospital. The study comprised 90 patients undergoing valve replacement under cardiopulmonary bypass. Patients were divided randomly into 3 groups. L-carnitine was added to the crystalloid cardioplegic solution for experimental group 1 (3 g/L) and experimental group 2 (6 g/L), whereas no L-carnitine was used in the control group. The remainder of the treatment was identical for all 3 groups. Serum was collected from each patient 1 hour before the surgery and at 2, 6, 24, and 72 hours after unclamping the aorta, and tissue samples were obtained before cardiac arrest and after unclamping the aorta. The postoperative levels of serum aspartate aminotransferase, creatine kinase, creatine kinase-MB isozyme, and lactic acid dehydrogenase and the apoptotic index were all lower in the 2 experimental groups than those in the control group. In addition, each of the aforementioned serum enzyme levels and the apoptotic index in all 3 groups significantly increased after unclamping the aorta compared with baseline levels taken before surgery. Bcl-2 expression was higher and Bax was lower in the 2 experimental groups compared with those of the control group after unclamping the aorta. However, there was no significant difference in all the postoperative indices between the 2 experimental groups. L-carnitine may reduce cardiopulmonary bypass-induced myocardial apoptosis through modulating the expressions of Bcl-2 and Bax, resulting in a protective effect from MIRI. Copyright © 2016 Elsevier Inc. All rights reserved.

Inhibition of SIRT1 by a small molecule induces apoptosis in breast cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalle, Arunasree M., E-mail: arunasreemk@ilsresearch.org; Mallika, A.; Badiger, Jayasree

2010-10-08

Research highlights: {yields} Novel small molecule SIRT1 inhibitor better than sirtinol. {yields} IC{sub 50} 500 nM. {yields} Specific tumor cytotoxicity towards breast cancer cells. {yields} Restoration of H3K9 acetylation levels to baseline when co-treated with SIRT1 activator (Activator X) and inhibitor (ILS-JGB-1741). -- Abstract: Overexpression of SIRT1, a NAD{sup +}-dependent class III histone deacetylases (HDACs), is implicated in many cancers and therefore could become a promising antitumor target. Here we demonstrate a small molecule SIRT1 inhibitor, ILS-JGB-1741(JGB1741) with potent inhibitory effects on the proliferation of human metastatic breast cancer cells, MDA-MB 231. The molecule has been designed using medicinal chemistrymore » approach based on known SIRT1 inhibitor, sirtinol. The molecule showed a significant inhibition of SIRT1 activity compared to sirtinol. Studies on the antitumor effects of JGB on three different cancer cell lines, K562, HepG2 and MDA-MB 231 showed an IC{sub 50} of 1, 10 and 0.5 {mu}M, respectively. Further studies on MDA-MB 231 cells showed a dose-dependent increase in K9 and K382 acetylation of H3 and p53, respectively. Results also demonstrated that JGB1741-induced apoptosis is associated with increase in cytochrome c release, modulation in Bax/Bcl2 ratio and cleavage of PARP. Flowcytometric analysis showed increased percentage of apoptotic cells, decrease in mitochondrial membrane potential and increase in multicaspase activation. In conclusion, the present study indicates the potent apoptotic effects of JGB1741 in MDA-MB 231 cells.« less

An NQO1-Initiated and p53-Independent Apoptotic Pathway Determines the Anti-Tumor Effect of Tanshinone IIA against Non-Small Cell Lung Cancer

PubMed Central

Wang, Guangji; Liu, Huiying; Wu, Xiaolan; Wang, Qiong; Liu, Miao; Liao, Ke; Wu, Mengqiu; Cheng, Xuefang; Hao, Haiping

2012-01-01

NQO1 is an emerging and promising therapeutic target in cancer therapy. This study was to determine whether the anti-tumor effect of tanshinone IIA (TSA) is NQO1 dependent and to elucidate the underlying apoptotic cell death pathways. NQO1+ A549 cells and isogenically matched NQO1 transfected and negative H596 cells were used to test the properties and mechanisms of TSA induced cell death. The in vivo anti-tumor efficacy and the tissue distribution properties of TSA were tested in tumor xenografted nude mice. We observed that TSA induced an excessive generation of ROS, DNA damage, and dramatic apoptotic cell death in NQO1+ A549 cells and H596-NQO1 cells, but not in NQO1− H596 cells. Inhibition or silence of NQO1 as well as the antioxidant NAC markedly reversed TSA induced apoptotic effects. TSA treatment significantly retarded the tumor growth of A549 tumor xenografts, which was significantly antagonized by dicoumarol co-treatment in spite of the increased and prolonged TSA accumulations in tumor tissues. TSA activated a ROS triggered, p53 independent and caspase dependent mitochondria apoptotic cell death pathway that is characterized with increased ratio of Bax to Bcl-xl, mitochondrial membrane potential disruption, cytochrome c release, and subsequent caspase activation and PARP-1 cleavage. The results of these findings suggest that TSA is a highly specific NQO1 target agent and is promising in developing as an effective drug in the therapy of NQO1 positive NSCLC. PMID:22848731

Protective effect of pyruvate against ethanol-induced apoptotic neurodegeneration in the developing rat brain.

PubMed

Ullah, Najeeb; Naseer, Muhammad Imran; Ullah, Ikram; Lee, Hae Young; Koh, Phil Ok; Kim, Myeong Ok

2011-12-01

Exposure to alcohol during the early stages of brain development can lead to neurological disorders in the CNS. Apoptotic neurodegeneration due to ethanol exposure is a main feature of alcoholism. Exposure of developing animals to alcohol (during the growth spurt period in particular) elicits apoptotic neuronal death and causes fetal alcohol effects (FAE) or fetal alcohol syndrome (FAS). A single episode of ethanol intoxication (at 5 g/kg) in a seven-day-old developing rat can activate the apoptotic cascade, leading to widespread neuronal death in the brain. In the present study, we investigated the potential protective effect of pyruvate against ethanol-induced neuroapoptosis. After 4h, a single dose of ethanol induced upregulation of Bax, release of mitochondrial cytochrome-c into the cytosol, activation of caspase-3 and cleavage of poly (ADP-ribose) polymerase (PARP-1), all of which promote apoptosis. These effects were all reversed by co-treatment with pyruvate at a well-tolerated dosage (1000 mg/kg). Histopathology performed at 24 and 48 h with Fluoro-Jade-B and cresyl violet stains showed that pyruvate significantly reduced the number of dead cells in the cerebral cortex, hippocampus and thalamus. Immunohistochemical analysis at 24h confirmed that ethanol-induced cell death is both apoptotic and inhibited by pyruvate. These findings suggest that pyruvate treatment attenuates ethanol-induced neuronal cell loss in the developing rat brain and holds promise as a safe therapeutic and neuroprotective agent in the treatment of neurodegenerative disorders in newborns and infants. Copyright © 2011 Elsevier Ltd. All rights reserved.

Pathogenic or Therapeutic Extracellular Vesicles in Rheumatic Diseases: Role of Mesenchymal Stem Cell-Derived Vesicles

PubMed Central

Cosenza, Stella; Ruiz, Maxime; Maumus, Marie; Jorgensen, Christian; Noël, Danièle

2017-01-01

Extracellular vesicles (EVs) are important mediators of cell-to-cell communication pathways via the transport of proteins, mRNA, miRNA and lipids. There are three main types of EVs, exosomes, microparticles and apoptotic bodies, which are classified according to their size and biogenesis. EVs are secreted by all cell types and their function reproduces that of the parental cell. They are involved in many biological processes that regulate tissue homeostasis and physiopathology of diseases. In rheumatic diseases, namely osteoarthritis (OA) and rheumatoid arthritis (RA), EVs have been isolated from synovial fluid and shown to play pathogenic roles contributing to progression of both diseases. By contrast, EVs may have therapeutic effect via the delivery of molecules that may stop disease evolution. In particular, EVs derived from mesenchymal stem cells (MSCs) reproduce the main functions of the parental cells and therefore represent the ideal type of EVs for modulating the course of either disease. The aim of this review is to discuss the role of EVs in OA and RA focusing on their potential pathogenic effect and possible therapeutic options. Special attention is given to MSCs and MSC-derived EVs for modulating OA and RA progression with the perspective of developing innovative therapeutic strategies. PMID:28441721

Lipase-catalyzed preparation of optically active 1'-acetoxychavicol acetates and their structure-activity relationships in apoptotic activity against human leukemia HL-60 cells.

PubMed

Azuma, Hideki; Miyasaka, Keita; Yokotani, Tsuyoshi; Tachibana, Taro; Kojima-Yuasa, Akiko; Matsui-Yuasa, Isao; Ogino, Kenji

2006-03-15

Structure-activity relationships of 1'-acetoxychavicol acetate (ACA) for apoptotic activity against human leukemia HL-60 cells were investigated using optically active ACA and various racemic ACA analogues. Natural-type (or with different acyl group) ACA showed a high apoptotic activity, but the ortho or meta isomers, 4-deacetoxy analogue, and the 2'-3' dehydrogenated derivative had no effect, or a weak activity. Optically active (R)- and (S)-ACA were prepared by a lipase-catalyzed esterification. Using a mixture of vinyl acetate-tetrahydrofuran (1:1 v/v) as a solvent at refluxing temperature, optically pure (R)- and (S)-ACA were obtained (99.7% ee and 99.1% ee, respectively). The apoptosis-inducing effects of both enantiomers were compared by means of an MTT assay and the detection of typical apoptotic phenomena (DNA fragmentation, caspase-3 activation, and PARP cleavage) and these two activities were almost equal. These results indicate that the essential moieties of ACA for apoptotic activity against HL-60 cells are both the presence of a 4-acetoxyl group and an unsaturated double bond between C-2' and C-3', and that the configuration at the 1'-position is unrelated to activity.

Investigations of Pro- and Anti-Apoptotic Factors Affecting African Swine Fever Virus Replication and Pathogenesis.

PubMed

Dixon, Linda K; Sánchez-Cordón, Pedro J; Galindo, Inmaculada; Alonso, Covadonga

2017-08-25

African swine fever virus (ASFV) is a large DNA virus that replicates predominantly in the cell cytoplasm and is the only member of the Asfarviridae family. The virus causes an acute haemorrhagic fever, African swine fever (ASF), in domestic pigs and wild boar resulting in the death of most infected animals. Apoptosis is induced at an early stage during virus entry or uncoating. However, ASFV encodes anti-apoptotic proteins which facilitate production of progeny virions. These anti-apoptotic proteins include A179L, a Bcl-2 family member; A224L, an inhibitor of apoptosis proteins (IAP) family member; EP153R a C-type lectin; and DP71L. The latter acts by inhibiting activation of the stress activated pro-apoptotic pathways pro-apoptotic pathways. The mechanisms by which these proteins act is summarised. ASF disease is characterised by massive apoptosis of uninfected lymphocytes which reduces the effectiveness of the immune response, contributing to virus pathogenesis. Mechanisms by which this apoptosis is induced are discussed.

Investigations of Pro- and Anti-Apoptotic Factors Affecting African Swine Fever Virus Replication and Pathogenesis

PubMed Central

Dixon, Linda K.; Sánchez-Cordón, Pedro J.; Galindo, Inmaculada

2017-01-01

African swine fever virus (ASFV) is a large DNA virus that replicates predominantly in the cell cytoplasm and is the only member of the Asfarviridae family. The virus causes an acute haemorrhagic fever, African swine fever (ASF), in domestic pigs and wild boar resulting in the death of most infected animals. Apoptosis is induced at an early stage during virus entry or uncoating. However, ASFV encodes anti-apoptotic proteins which facilitate production of progeny virions. These anti-apoptotic proteins include A179L, a Bcl-2 family member; A224L, an inhibitor of apoptosis proteins (IAP) family member; EP153R a C-type lectin; and DP71L. The latter acts by inhibiting activation of the stress activated pro-apoptotic pathways pro-apoptotic pathways. The mechanisms by which these proteins act is summarised. ASF disease is characterised by massive apoptosis of uninfected lymphocytes which reduces the effectiveness of the immune response, contributing to virus pathogenesis. Mechanisms by which this apoptosis is induced are discussed. PMID:28841179

Cardio Protective Effects of Lumbrokinase and Dilong on Second-Hand Smoke-Induced Apoptotic Signaling in the Heart of a Rat Model.

PubMed

Liao, Hung-En; Lai, Chao-Hung; Ho, Tsung-Jung; Yeh, Yu-Lan; Jong, Gwo-Ping; Kuo, Wu-Hsien; Chung, Li-Chin; Pai, Pei-ying; Wen, Su-Ying; Huang, Chih-Yang

2015-06-30

Exposure to second-hand tobacco smoke (SHS) has been epidemiologically linked to heart disease among non-smokers. However, the molecular mechanism behind SHS-induced cardiac disease is not well known. This study found that SD rats exposed to cigarette smoke at a dose of 10 cigarettes for 30 min twice a day for 1 month had a reduced left ventricle-to-tibia length ratio (mg/mm), increased cardiomyocyte apoptosis by TUNEL assay and a wider interstitial space by H&E staining. However, lumbrokinase and dilong both reversed the effects of SHS. Western blotting demonstrated significantly increased expression of the pro-apoptotic protein caspase-3 in the hearts of the rats exposed to SHS. Elevated protein expression levels of Fas, FADD and the apoptotic initiator activated caspase-8, a molecule in the death-receptor-dependent pathway, coupled with increased t-Bid and apoptotic initiator activated caspase-9 were found. Molecules in the mitochondria-dependent pathway, which disrupts mitochondrial membrane potential, were also found in rats exposed to SHS. These factors indicate myocardial apoptosis. However, treatment with lumbrokinase and dilong inhibited SHS-induced apoptosis. Regarding regulation of the survival pathway, we found in western blot analysis that cardiac protein expression of pAkt, Bcl2, and Bcl-xL was significantly down-regulated in rats exposed to SHS. These effects were reversed with lumbrokinase and dilong treatment. The effects of SHS on cardiomyocytes were also found to be mediated by the Fas death receptor-dependent apoptotic pathway, an unbalanced mitochondria membrane potential and decreased survival signaling. However, treatment with both lumbrokinase and dilong inhibited the effects of SHS. Our data suggest that lumbrokinase and dilong may prevent heart disease in SHS-exposed non-smokers.

Adenosine A1 receptor: A neuroprotective target in light induced retinal degeneration.

PubMed

Soliño, Manuel; López, Ester María; Rey-Funes, Manuel; Loidl, César Fabián; Larrayoz, Ignacio M; Martínez, Alfredo; Girardi, Elena; López-Costa, Juan José

2018-01-01

Light induced retinal degeneration (LIRD) is a useful model that resembles human retinal degenerative diseases. The modulation of adenosine A1 receptor is neuroprotective in different models of retinal injury. The aim of this work was to evaluate the potential neuroprotective effect of the modulation of A1 receptor in LIRD. The eyes of rats intravitreally injected with N6-cyclopentyladenosine (CPA), an A1 agonist, which were later subjected to continuous illumination (CI) for 24 h, showed retinas with a lower number of apoptotic nuclei and a decrease of Glial Fibrillary Acidic Protein (GFAP) immunoreactive area than controls. Lower levels of activated Caspase 3 and GFAP were demonstrated by Western Blot (WB) in treated animals. Also a decrease of iNOS, TNFα and GFAP mRNA was demonstrated by RT-PCR. A decrease of Iba 1+/MHC-II+ reactive microglial cells was shown by immunohistochemistry. Electroretinograms (ERG) showed higher amplitudes of a-wave, b-wave and oscillatory potentials after CI compared to controls. Conversely, the eyes of rats intravitreally injected with dipropylcyclopentylxanthine (DPCPX), an A1 antagonist, and subjected to CI for 24 h, showed retinas with a higher number of apoptotic nuclei and an increase of GFAP immunoreactive area compared to controls. Also, higher levels of activated Caspase 3 and GFAP were demonstrated by Western Blot. The mRNA levels of iNOS, nNOS and inflammatory cytokines (IL-1β and TNFα) were not modified by DPCPX treatment. An increase of Iba 1+/MHC-II+ reactive microglial cells was shown by immunohistochemistry. ERG showed that the amplitudes of a-wave, b-wave, and oscillatory potentials after CI were similar to control values. A single pharmacological intervention prior illumination stress was able to swing retinal fate in opposite directions: CPA was neuroprotective, while DPCPX worsened retinal damage. In summary, A1 receptor agonism is a plausible neuroprotective strategy in LIRD.

Deoxyelephantopin from Elephantopus scaber L. induces cell-cycle arrest and apoptosis in the human nasopharyngeal cancer CNE cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, Miaoxian; Chung, Hau Yin, E-mail: anthonychung@cuhk.edu.hk; Food and Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong SAR

2011-07-29

Highlights: {yields} Deoxyelephantopin (ESD) inhibited cell proliferation in the human nasopharyngeal cancer CNE cells. {yields} ESD induced cell cycle arrest in S and G2/M phases via modulation of cell cycle regulatory proteins. {yields} ESD triggered apoptosis by dysfunction of mitochondria and induction of both intrinsic and extrinsic apoptotic signaling pathways. {yields} ESD also triggered Akt, ERK, and JNK signaling pathways. -- Abstract: Deoxyelephantopin (ESD), a naturally occurring sesquiterpene lactone present in the Chinese medicinal herb, Elephantopus scaber L. exerted anticancer effects on various cultured cancer cells. However, the cellular mechanisms by which it controls the development of the cancer cellsmore » are unavailable, particularly the human nasopharyngeal cancer CNE cells. In this study, we found that ESD inhibited the CNE cell proliferation. Cell cycle arrest in S and G2/M phases was also found. Western blotting analysis showed that modulation of cell cycle regulatory proteins was responsible for the ESD-induced cell cycle arrest. Besides, ESD also triggered apoptosis in CNE cells. Dysfunction in mitochondria was found to be associated with the ESD-induced apoptosis as evidenced by the loss of mitochondrial membrane potential ({Delta}{Psi}m), the translocation of cytochrome c, and the regulation of Bcl-2 family proteins. Despite the Western blotting analysis showed that both intrinsic and extrinsic apoptotic pathways (cleavage of caspases-3, -7, -8, -9, and -10) were triggered in the ESD-induced apoptosis, additional analysis also showed that the induction of apoptosis could be achieved by the caspase-independent manner. Besides, Akt, ERK and JNK pathways were found to involve in ESD-induced cell death. Overall, our findings provided the first evidence that ESD induced cell cycle arrest, and apoptosis in CNE cells. ESD could be a potential chemotherapeutic agent in the treatment of nasopharyngeal cancer (NPC).« less

6-Shogaol exerts anti-proliferative and pro-apoptotic effects through the modulation of STAT3 and MAPKs signaling pathways.

PubMed

Kim, Sung-Moo; Kim, Chulwon; Bae, Hang; Lee, Jong Hyun; Baek, Seung Ho; Nam, Dongwoo; Chung, Won-Seok; Shim, Bum Sang; Lee, Seok-Geun; Kim, Sung-Hoon; Sethi, Gautam; Ahn, Kwang Seok

2015-10-01

6-shogaol (6SG), one of active ingredients in ginger (Zingiber officinale), is known to exhibit anti-proliferative, anti-metastatic, and pro-apoptotic activities through a mechanism that is not fully elucidated. Because the aberrant activation of STAT3 and MAPKs have been associated with regulation of proliferation, invasion, and metastasis of tumors, we hypothesized that 6SG modulates the activation of STAT3 and MAPKs activation in tumor cells. We found that 6SG strongly inhibited constitutive phosphorylation of STAT3 through inhibition of the activation of upstream JAK2 and c-Src kinases and nuclear translocation of STAT3 on both MDA-MB231 and DU145 cells. Also, 6SG caused the activation of JNK, p38 MAPK, and ERK. Inhibition of ROS generation by N-acetylcysteine (NAC) significantly prevented 6SG-induced apoptosis. 6SG induced apoptosis as characterized by cleavage of PARP, accumulation of cells in subG1 phase, positive Annexin V binding, down-regulation of STAT3-regulated proteins, and activation of caspase-8, -9, -3 in both MDA-MB231 cells. Compared with other analogues of 6SG, such as 6-gingerol (6G), 8-gingerol (8G), and 10-gingerol (10G), 6SG was found to be the most potent blocker of STAT3 activation. We observed that the administration of 6SG alone significantly suppressed the growth of the tumor. As compared to the vehicle control, 6SG also suppressed the expression of STAT3-regulated gene products such as Bcl-2, Bcl-xL, and Survivin in tumor tissues. Overall, these findings suggest that 6SG can interfere with multiple signaling cascades involved in tumorigenesis and can be used as a potential therapeutic candidate for both the prevention and treatment of cancer. © 2014 Wiley Periodicals, Inc.

Exposure to the Neurotoxic Dinoflagellate, Alexandrium catenella, Induces Apoptosis of the Hemocytes of the Oyster, Crassostrea gigas

PubMed Central

Medhioub, Walid; Ramondenc, Simon; Vanhove, Audrey Sophie; Vergnes, Agnes; Masseret, Estelle; Savar, Veronique; Amzil, Zouher; Laabir, Mohamed; Rolland, Jean Luc

2013-01-01

This study assessed the apoptotic process occurring in the hemocytes of the Pacific oyster, Crassostrea gigas, exposed to Alexandrium catenella, a paralytic shellfish toxins (PSTs) producer. Oysters were experimentally exposed during 48 h to the toxic algae. PSTs accumulation, the expression of 12 key apoptotic-related genes, as well as the variation of the number of hemocytes in apoptosis was measured at time intervals during the experiment. Results show a significant increase of the number of hemocytes in apoptosis after 29 h of exposure. Two pro-apoptotic genes (Bax and Bax-like) implicated in the mitochondrial pathway were significantly upregulated at 21 h followed by the overexpression of two caspase executor genes (caspase-3 and caspase-7) at 29 h, suggesting that the intrinsic pathway was activated. No modulation of the expression of genes implicated in the cell signaling Fas-Associated protein with Death Domain (FADD) and initiation-phase (caspase-2) was observed, suggesting that only the extrinsic pathway was not activated. Moreover, the clear time-dependent upregulation of five (Bcl2, BI-1, IAP1, IAP7B and Hsp70) inhibitors of apoptosis-related genes associated with the return to the initial number of hemocytes in apoptosis at 48 h of exposure suggests the involvement of strong regulatory mechanisms of apoptosis occurring in the hemocytes of the Pacific oyster. PMID:24317471

Identification of novel binding partners (annexins) for the cell death signal phosphatidylserine and definition of their recognition motif.

PubMed

Rosenbaum, Sabrina; Kreft, Sandra; Etich, Julia; Frie, Christian; Stermann, Jacek; Grskovic, Ivan; Frey, Benjamin; Mielenz, Dirk; Pöschl, Ernst; Gaipl, Udo; Paulsson, Mats; Brachvogel, Bent

2011-02-18

Identification and clearance of apoptotic cells prevents the release of harmful cell contents thereby suppressing inflammation and autoimmune reactions. Highly conserved annexins may modulate the phagocytic cell removal by acting as bridging molecules to phosphatidylserine, a characteristic phagocytosis signal of dying cells. In this study five members of the structurally and functionally related annexin family were characterized for their capacity to interact with phosphatidylserine and dying cells. The results showed that AnxA3, AnxA4, AnxA13, and the already described interaction partner AnxA5 can bind to phosphatidylserine and apoptotic cells, whereas AnxA8 lacks this ability. Sequence alignment experiments located the essential amino residues for the recognition of surface exposed phosphatidylserine within the calcium binding motifs common to all annexins. These amino acid residues were missing in the evolutionary young AnxA8 and when they were reintroduced by site directed mutagenesis AnxA8 gains the capability to interact with phosphatidylserine containing liposomes and apoptotic cells. By defining the evolutionary conserved amino acid residues mediating phosphatidylserine binding of annexins we show that the recognition of dying cells represent a common feature of most annexins. Hence, the individual annexin repertoire bound to the cell surface of dying cells may fulfil opsonin-like function in cell death recognition.

Nanosurface design of dental implants for improved cell growth and function

NASA Astrophysics Data System (ADS)

Pan, Hsu-An; Hung, Yao-Ching; Chiou, Jin-Chern; Tai, Shih-Ming; Chen, Hsin-Hung; Huang, G. Steven

2012-08-01

A strategy was proposed for the topological design of dental implants based on an in vitro survey of optimized nanodot structures. An in vitro survey was performed using nanodot arrays with dot diameters ranging from 10 to 200 nm. MG63 osteoblasts were seeded on nanodot arrays and cultured for 3 days. Cell number, percentage undergoing apoptotic-like cell death, cell adhesion and cytoskeletal organization were evaluated. Nanodots with a diameter of approximately 50 nm enhanced cell number by 44%, minimized apoptotic-like cell death to 2.7%, promoted a 30% increase in microfilament bundles and maximized cell adhesion with a 73% increase in focal adhesions. An enhancement of about 50% in mineralization was observed, determined by von Kossa staining and by Alizarin Red S staining. Therefore, we provide a complete range of nanosurfaces for growing osteoblasts to discriminate their nanoscale environment. Nanodot arrays present an opportunity to positively and negatively modulate cell behavior and maturation. Our results suggest a topological approach which is beneficial for the design of dental implants.

HIV-1 Tat targets Tip60 to impair the apoptotic cell response to genotoxic stresses

PubMed Central

Col, Edwige; Caron, Cécile; Chable-Bessia, Christine; Legube, Gaelle; Gazzeri, Sylvie; Komatsu, Yasuhiko; Yoshida, Minoru; Benkirane, Monsef; Trouche, Didier; Khochbin, Saadi

2005-01-01

HIV-1 transactivator Tat uses cellular acetylation signalling by targeting several cellular histone acetyltransferases (HAT) to optimize its various functions. Although Tip60 was the first HAT identified to interact with Tat, the biological significance of this interaction has remained obscure. We had previously shown that Tat represses Tip60 HAT activity. Here, a new mechanism of Tip60 neutralization by Tat is described, where Tip60 is identified as a substrate for the newly reported p300/CBP-associated E4-type ubiquitin-ligase activity, and Tat uses this mechanism to induce the polyubiquitination and degradation of Tip60. Tip60 targeting by Tat results in a dramatic impairment of the Tip60-dependent apoptotic cell response to DNA damage. These data reveal yet unknown strategies developed by HIV-1 to increase cell resistance to genotoxic stresses and show a role of Tat as a modulator of cellular protein ubiquitination. PMID:16001085

Hepatic Leukemia Factor Promotes Resistance To Cell Death: Implications For Therapeutics and Chronotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waters, Katrina M.; Sontag, Ryan L.; Weber, Thomas J.

Physiological variation related to circadian rhythms and aberrant gene expression patterns are believed to modulate therapeutic efficacy, but the precise molecular determinants remain unclear. Here we examine the regulation of cell death by hepatic leukemia factor (HLF), which is an output regulator of circadian rhythms and is aberrantly expressed in human cancers, using an ectopic expression strategy in JB6 mouse epidermal cells and human keratinocytes. Ectopic HLF expression inhibited cell death in both JB6 cells and human keratinocytes, as induced by serum-starvation, tumor necrosis factor alpha and ionizing radiation. Microarray analysis indicates that HLF regulates a complex multi-gene transcriptional programmore » encompassing upregulation of anti-apoptotic genes, downregulation of pro-apoptotic genes, and many additional changes that are consistent with an anti-death program. Collectively, our results demonstrate that ectopic expression of HLF, an established transcription factor that cycles with circadian rhythms, can recapitulate many features associated with circadian-dependent physiological variation.« less

Role of endothelin-1 and its receptors, ETA and ETB, in the survival of human vascular endothelial cells.

PubMed

Mikhail, Marianne; Vachon, Pierre H; D'Orléans-Juste, Pedro; Jacques, Danielle; Bkaily, Ghassan

2017-10-01

Our previous work showed the presence of endothelin-1 (ET-1) receptors, ET A and ET B , in human vascular endothelial cells (hVECs). In this study, we wanted to verify whether ET-1 plays a role in the survival of hVECs via the activation of its receptors ET A and (or) ET B (ET A R and ET B R, respectively). Our results showed that treatment of hVECs with ET-1 prevented apoptosis induced by genistein, an effect that was mimicked by treatment with ET B R-specific agonist IRL1620. Furthermore, blockade of ET B R with the selective ET B R antagonist A-192621 prevented the anti-apoptotic effect of ET-1 in hVECs. However, activation of ET A receptor alone did not seem to contribute to the anti-apoptotic effect of ET-1. In addition, the anti-apoptotic effect of ET B R was found to be associated with caspase 3 inhibition and does not depend on the density of this type of receptor. In conclusion, our results showed that ET-1 possesses an anti-apoptotic effect in hVECs and that this effect is mediated, to a great extent, via the activation of ET B R. This study revealed a new role for ET B R in the survival of hVECs.

Fatty acid synthase regulates the chemosensitivity of breast cancer cells to cisplatin-induced apoptosis.

PubMed

Al-Bahlani, Shadia; Al-Lawati, Hanaa; Al-Adawi, Moza; Al-Abri, Nadia; Al-Dhahli, Buthaina; Al-Adawi, Kawther

2017-06-01

Fatty acid synthase (FASN) is a key enzyme in fat biosynthesis that is over-expressed in advanced breast cancer stages. Cisplatin (CDDP) is a platinum-based drug used in the treatment of certain types of this disease. Although it was shown that FASN inhibition induced apoptosis by enhancing the cytotoxicity of certain drugs in breast cancer, its role in regulating the chemosensitivity of different types of breast cancer cells to CDDP-induced apoptosis is not established yet. Therefore, two different breast cancer cell lines; triple negative breast cancer (TNBC; MDA-MB-231) and triple positive breast cancer (TPBC; BT-474) cells were used to examine such role. We show that TNBC cells had naturally less fat content than TPBC cells. Subsequently, the fat content increased in both cells when treated with Palmitate rather than Oleate, whereas both fatty acids produced apoptotic ultra-structural effects and attenuated FASN expression. However, Oleate increased FASN expression in TPBC cells. CDDP decreased FASN expression and increased apoptosis in TNBC cells. These effects were further enhanced by combining CDDP with fatty acids. We also illustrate that the inhibition of FASN by either siRNA or exogenous inhibitor decreased CDDP-induced apoptosis in TPBC cells suggesting its role as an apoptotic factor, while an opposite finding was observed in TNBC cells when siRNA and fatty acids were used, suggesting its role as a survival factor. To our knowledge, we are the first to demonstrate a dual role of FASN in CDDP-induced apoptosis in breast cancer cells and how it can modulate their chemosensitivity.

Cross-talk between miR-471-5p and autophagy component proteins regulates LC3-associated phagocytosis (LAP) of apoptotic germ cells.

PubMed

Panneerdoss, Subbarayalu; Viswanadhapalli, Suryavathi; Abdelfattah, Nourhan; Onyeagucha, Benjamin C; Timilsina, Santosh; Mohammad, Tabrez A; Chen, Yidong; Drake, Michael; Vuori, Kristiina; Kumar, T Rajendra; Rao, Manjeet K

2017-09-19

Phagocytic clearance of apoptotic germ cells by Sertoli cells is vital for germ cell development and differentiation. Here, using a tissue-specific miRNA transgenic mouse model, we show that interaction between miR-471-5p and autophagy member proteins regulates clearance of apoptotic germ cells via LC3-associated phagocytosis (LAP). Transgenic mice expressing miR-471-5p in Sertoli cells show increased germ cell apoptosis and compromised male fertility. Those effects are due to defective engulfment and impaired LAP-mediated clearance of apoptotic germ cells as miR-471-5p transgenic mice show lower levels of Dock180, LC3, Atg12, Becn1, Rab5 and Rubicon in Sertoli cells. Our results reveal that Dock180 interacts with autophagy member proteins to constitute a functional LC3-dependent phagocytic complex. We find that androgen regulates Sertoli cell phagocytosis by controlling expression of miR-471-5p and its target proteins. These findings suggest that recruitment of autophagy machinery is essential for efficient clearance of apoptotic germ cells by Sertoli cells using LAP.Although phagocytic clearance of apoptotic germ cells by Sertoli cells is essential for spermatogenesis, little of the mechanism is known. Here the authors show that Sertoli cells employ LC3-associated phagocytosis (LAP) by recruiting autophagy member proteins to clear apoptotic germ cells.

Preparation of anastrozole loaded PEG-PLA nanoparticles: evaluation of apoptotic response of breast cancer cell lines.

PubMed

Alyafee, Yusra A; Alaamery, Manal; Bawazeer, Shahad; Almutairi, Mansour S; Alghamdi, Badr; Alomran, Nawaf; Sheereen, Atia; Daghestani, Maha; Massadeh, Salam

2018-01-01

Anastrozole (ANS) is an aromatase inhibitor that is widely used as a treatment for breast cancer in postmenopausal women. Despite the wide use of ANS, it is associated with serious side effects due to uncontrolled delivery. In addition, ANS exhibits low solubility and short plasma half-life. Nanotechnology-based drug delivery has the potential to enhance the efficacy of drugs and overcome undesirable side effects. In this study, we aimed to prepare novel ANS-loaded PLA-PEG-PLA nanoparticles (ANS-NPs) and to compare the apoptotic response of MCF-7 cell line to both ANS and ANS-loaded NPs. ANS-NPs were synthesized using double emulsion method and characterized using different methods. The apoptotic response was evaluated by assessing cell viability, morphology, and studying changes in the expression of MAPK3 , MCL1 , and c-MYC apoptotic genes in MCF-7 cell lines. ANS was successfully encapsulated within PLA-PEG-PLA, forming monodisperse therapeutic NPs with an encapsulation efficiency of 67%, particle size of 186±27.13, and a polydispersity index of 0.26±0.11 with a sustained release profile extended over 144 hours. In addition, results for cell viability and for gene expression represent a similar apoptotic response between the free ANS and ANS-NPs. The synthesized ANS-NPs showed a similar therapeutic effect as the free ANS, which provides a rationale to pursue pre-clinical evaluation of ANS-NPs on animal models.

Deoxycholic acid modulates cell death signaling through changes in mitochondrial membrane properties[S

PubMed Central

Sousa, Tânia; Castro, Rui E.; Pinto, Sandra N.; Coutinho, Ana; Lucas, Susana D.; Moreira, Rui; Rodrigues, Cecília M. P.; Prieto, Manuel; Fernandes, Fábio

2015-01-01

Cytotoxic bile acids, such as deoxycholic acid (DCA), are responsible for hepatocyte cell death during intrahepatic cholestasis. The mechanisms responsible for this effect are unclear, and recent studies conflict, pointing to either a modulation of plasma membrane structure or mitochondrial-mediated toxicity through perturbation of mitochondrial outer membrane (MOM) properties. We conducted a comprehensive comparative study of the impact of cytotoxic and cytoprotective bile acids on the membrane structure of different cellular compartments. We show that DCA increases the plasma membrane fluidity of hepatocytes to a minor extent, and that this effect is not correlated with the incidence of apoptosis. Additionally, plasma membrane fluidity recovers to normal values over time suggesting the presence of cellular compensatory mechanisms for this perturbation. Colocalization experiments in living cells confirmed the presence of bile acids within mitochondrial membranes. Experiments with active isolated mitochondria revealed that physiologically active concentrations of DCA change MOM order in a concentration- and time-dependent manner, and that these changes preceded the mitochondrial permeability transition. Importantly, these effects are not observed on liposomes mimicking MOM lipid composition, suggesting that DCA apoptotic activity depends on features of mitochondrial membranes that are absent in protein-free mimetic liposomes, such as the double-membrane structure, lipid asymmetry, or mitochondrial protein environment. In contrast, the mechanism of action of cytoprotective bile acids is likely not associated with changes in cellular membrane structure. PMID:26351365

Oncostatic action of melatonin: facts and question marks.

PubMed

Pawlikowski, Marek; Winczyk, Katarzyna; Karasek, Michal

2002-04-01

The paper presents the data concerning the in vivo effects of melatonin on experimentally-induced tumors in animals and the in vitro effects on animal and human tumor cells. The majority of experimental tumors responded to the melatonin treatment with growth inhibition. However, some negative or opposite results (i.e. stimulation of tumor instead of inhibition) were also reported. Some of the negative results can be attributed to the improper timing of melatonin administration. Melatonin was also shown to inhibit the growth of several animal and human tumor cell lines in vitro. On the basis of these experiments, a hypothesis of the oncostatic action of melatonin was put forward. The mechanism of the postulated action is complex and probably includes: 1) modulation of the endocrine system; 2) modulation of the immune system; 3) the direct oncostatic action of melatonin on tumor cells. The latter includes the recently discovered anti-oxidative action which probably plays an important role in the countering the DNA damage during the radiation challenge or the exposure to chemical carcinogens. It also includes the antiproliferative and pro-apoptotic effects exerted via melatonin receptors expressed by tumor cells. The involvement of the membrane melatonin receptors is mainly assumed. However, the recent data from our and other laboratories suggest also the involvement of RZR/ROR receptors (the putative melatonin nuclear receptors) in both melatonin-induced proliferation inhibition and apoptosis.

Magnolol Reduces Renal Ischemia and Reperfusion Injury via Inhibition of Apoptosis.

PubMed

Tang, Chia-Yu; Lai, Chang-Chi; Huang, Po-Hsun; Yang, An-Han; Chiang, Shu-Chiung; Huang, Po-Chao; Tseng, Kuo-Wei; Huang, Cheng-Hsiung

2017-01-01

Magnolol, a constituent of the bark of Magnolia officinalis, has been reported to decrease myocardial stunning and infarct size. In this study, we investigated whether magnolol can reduce renal ischemia and reperfusion (I/R) injury. Renal I/R, induced by a 60-min occlusion of bilateral renal arteries and a 24-h reperfusion, significantly increased blood urea nitrogen (BUN) and creatinine levels, and caused histological damage to the kidneys of rats. Apoptosis, as evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining and caspase-3 activation, was significantly increased in the kidneys. Furthermore, serum levels of tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]), interleukin-1β (IL-1β), and interleukin-6 (IL-6) were significantly elevated, while the interleukin-10 (IL-10) level was suppressed. However, intravenous pretreatment with magnolol at doses of 0.003[Formula: see text]mg/kg and 0.006[Formula: see text]mg/kg 10[Formula: see text]min before renal I/R significantly limited the increases of BUN, creatinine, the histological damage, and apoptosis in the kidneys. The increases in TNF-[Formula: see text], IL-1β, and IL-6, and the decrease in IL-10 were also significantly inhibited. Additionally, magnolol increased Bcl-2 and decreased Bax in the kidneys. Phosphorylation of the prosurvival kinases, including Akt and extracellular signal-regulated kinases 1 and 2 (ERK1/2), was elevated, while phosphorylation of the pro-apoptotic mitogen-activated protein kinases, including p38 and c-Jun N-terminal kinase (JNK), was suppressed. In conclusion, magnolol reduces renal I/R injury. The underlying mechanisms for this effect might be related to the prevention of apoptosis, possibly via the inhibition of both extrinsic and intrinsic apoptotic pathways, including the reduction of TNF-[Formula: see text] production and the modulation of pro- and anti-apoptotic signaling elements.

Apoptotic actions of p53 require transcriptional activation of PUMA and do not involve a direct mitochondrial/cytoplasmic site of action in postnatal cortical neurons.

PubMed

Uo, Takuma; Kinoshita, Yoshito; Morrison, Richard S

2007-11-07

Recent studies in non-neuronal cells have shown that the tumor suppressor p53 can promote cell death through a transcription-independent mechanism involving its direct action with a subset of Bcl-2 family member proteins in the cytosol and at the mitochondria. In cultured cortical neurons, however, we could not find evidence supporting a significant contribution of the cytosolic/mitochondrial p53 pathway, and available evidence instead corroborated the requirement for the transcriptional activity of p53. When directly targeted to the cytosol/mitochondria, wild-type p53 lost its apoptosis-inducing activity in neurons but not in non-neuronal cells. The N-terminal p53 fragment (transactivation and proline-rich domains), which induces apoptosis in non-neuronal cells via the cytosolic/mitochondrial pathway, displayed no apoptogenic activity in neurons. In neuronal apoptosis induced by camptothecin or an MDM2 (murine double minute 2) inhibitor, nutlin-3, endogenous p53 protein did not accumulate in the cytosol/mitochondria, and transcriptional inhibition after p53 induction effectively blocked cell death. In addition, overexpression of a dominant-negative form of p53 (R273H) completely suppressed induction of proapoptotic p53 target genes and cell death. PUMA (p53-upregulated modulator of apoptosis) was one such gene induced by camptothecin, and its overexpression was sufficient to induce Bax (Bcl-2-associated X protein)-dependent neuronal death, whereas Noxa was not apoptogenic. These results collectively demonstrate that, in contrast to non-neuronal cells, the apoptotic activity of p53 in postnatal cortical neurons does not rely on its direct action at the cytosol/mitochondria but is exclusively mediated through its transcription-dependent functions. The uniqueness of p53-mediated apoptotic signaling in postnatal cortical neurons was further illustrated by the dispensable function of the proline-rich domain of p53.

NELL2 function in the protection of cells against endoplasmic reticulum stress.

PubMed

Kim, Dong Yeol; Kim, Han Rae; Kim, Kwang Kon; Park, Jeong Woo; Lee, Byung Ju

2015-01-01

Continuous intra- and extracellular stresses induce disorder of Ca(2+) homeostasis and accumulation of unfolded protein in the endoplasmic reticulum (ER), which results in ER stress. Severe long-term ER stress triggers apoptosis signaling pathways, resulting in cell death. Neural epidermal growth factor-like like protein 2 (NELL2) has been reported to be important in protection of cells from cell death-inducing environments. In this study, we investigated the cytoprotective effect of NELL2 in the context of ER stress induced by thapsigargin, a strong ER stress inducer, in Cos7 cells. Overexpression of NELL2 prevented ER stress-mediated apoptosis by decreasing expression of ER stress-induced C/EBP homologous protein (CHOP) and increasing ER chaperones. In this context, expression of anti-apoptotic Bcl-xL was increased by NELL2, whereas NELL2 decreased expression of pro-apoptotic proteins, such as cleaved caspases 3 and 7. This anti-apoptotic effect of NELL2 is likely mediated by extracellular signal-regulated kinase (ERK) signaling, because its inhibitor, U0126, inhibited effects of NELL2 on the expression of anti- and pro-apoptotic proteins and on the protection from ER stress-induced cell death.

Apoptotic effects of ε-viniferin in combination with cis-platin in C6 cells.

PubMed

Özdemir, Filiz; Apaydın, Elif; Önder, Nur İpek; Şen, Mesut; Ayrım, Aysun; Öğünç, Yüksel; İncesu, Zerrin

2018-02-23

Glioblastoma (GBM) is one of the most common and lethal forms of primary brain tumors in human adults. Treatment options are limited, and in most cases ineffective. Natural products are sources of novel compounds endowed with therapeutic properties in many human diseases like cancer. ε-viniferin is a resveratrol dimer and well known for having antiproliferative and apoptotic effects on cancer cells. Cisplatin is a platinum containing anti-cancer drug. In this study, we aimed to investigate antiproliferative and apoptotic effects of using cis-platin and ε-viniferin alone or in combined treatment of C6 cells. Cell proliferation was detected by WST-1. Mitochondrial membrane potential changes in the cells (ΔΨm) were evaluated using cationic dye JC1. Apoptotic index which is a hallmark of late apoptosis was detected by using Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method and apoptotic alterations were observed by transmission electron microscope (TEM). Activation of caspase-8, -9, -3 in C6 cells at various incubation periods was measured by flow cytometer. Apoptotic index increased at highest level in only combined treatment cells (91.6%) after 48 h incubation. These results were supported by TEM images. Caspase-8 activation in C6 cells increased to a maximum (12.5%) after 6 h by using combined cis-platin/ε-viniferin treatment (13.25/95 μM). Caspase-9 was activated at 44.5% after combined treatment for 24 h. This rate is higher than using cis-platin (14.2%) or ε-viniferin (43.3%) alone. The combined 13.25 μM/cisplatin and 95 μM ε-viniferin treatment caused maximum caspase-3 activation in C6 cells (15.5%) at the end of the 72 h incubation. In conclusion, it was observed that caspase-8, -9, -3 activation which was determined in vitro, trigerred apoptotic mechanism in C6 cells by using low concentrations of combined cis-platin and ε-viniferin.

Cytoprotective Effect of Epigallocatechin Gallate (EGCG)-5'-O-α-Glucopyranoside, a Novel EGCG Derivative.

PubMed

Han, Sang Yun; Kim, Eunji; Hwang, Kyeonghwan; Ratan, Zubair Ahmed; Hwang, Hyunsik; Kim, Eun-Mi; Kim, Doman; Park, Junseong; Cho, Jae Youl

2018-05-15

Epigallocatechin gallate (EGCG) is a well-studied polyphenol with antioxidant effects. Since EGCG has low solubility and stability, many researchers have modified EGCG residues to ameliorate these problems. A novel EGCG derivative, EGCG-5'- O -α-glucopyranoside (EGCG-5'Glu), was synthesized, and its characteristics were investigated. EGCG-5'Glu showed antioxidant effects in cell and cell-free systems. Under SNP-derived radical exposure, EGCG-5'Glu decreased nitric oxide (NO) production, and recovered ROS-mediated cell viability. Moreover, EGCG-5'Glu regulated apoptotic pathways (caspases) and cell survival molecules (phosphoinositide 3-kinase (PI3K) and phosphoinositide-dependent kinase 1 (PDK1)). In another radical-induced condition, ultraviolet B (UVB) irradiation, EGCG-5'Glu protected cells from UVB and regulated the PI3K/PDK1/AKT pathway. Next, the proliferative effect of EGCG-5'Glu was examined. EGCG-5'Glu increased cell proliferation by modulating nuclear factor (NF)-κB activity. EGCG-5'Glu protects and repairs cells from external damage via its antioxidant effects. These results suggest that EGCG-5'Glu could be used as a cosmetics ingredient or dietary supplement.

The role of apoptosis repressor with a CARD domain (ARC) in the therapeutic resistance of renal cell carcinoma (RCC): the crucial role of ARC in the inhibition of extrinsic and intrinsic apoptotic signalling.

PubMed

Toth, Csaba; Funke, Sarah; Nitsche, Vanessa; Liverts, Anna; Zlachevska, Viktoriya; Gasis, Marcia; Wiek, Constanze; Hanenberg, Helmut; Mahotka, Csaba; Schirmacher, Peter; Heikaus, Sebastian

2017-05-02

Renal cell carcinomas (RCCs) display broad resistance against conventional radio- and chemotherapies, which is due at least in part to impairments in both extrinsic and intrinsic apoptotic pathways. One important anti-apoptotic factor that is strongly overexpressed in RCCs and known to inhibit both apoptotic pathways is ARC (apoptosis repressor with a CARD domain). Expression and subcellular distribution of ARC in RCC tissue samples and RCC cell lines were determined by immunohistochemistry and fluorescent immunohistochemistry, respectively. Extrinsic and intrinsic apoptosis signalling were induced by TRAIL (TNF-related apoptosis-inducing ligand), ABT-263 or topotecan. ARC knock-down was performed in clearCa-12 cells using lentiviral transduction of pGIPZ. shRNAmir constructs. Extrinsic respectively intrinsic apoptosis were induced by TRAIL (TNF-related apoptosis-inducing ligand), ABT263 or topotecan. Potential synergistic effects were tested by pre-treatment with topotecan and subsequent treatment with ABT263. Activation of different caspases and mitochondrial depolarisation (JC-1 staining) were analysed by flow cytometry. Protein expression of Bcl-2 family members and ARC in RCC cell lines was measured by Western blotting. Statistical analysis was performed by Student's t-test. Regarding the extrinsic pathway, ARC knockdown strongly enhanced TRAIL-induced apoptosis by increasing the activation level of caspase-8. Regarding the intrinsic pathway, ARC, which was only weakly expressed in the nuclei of RCCs in vivo, exerted its anti-apoptotic effect by impairing mitochondrial activation rather than inhibiting p53. Topotecan- and ABT-263-induced apoptosis was strongly enhanced following ARC knockdown in RCC cell lines. In addition, topotecan pre-treatment enhanced ABT-263-induced apoptosis and this effect was amplified in ARC-knockdown cells. Taken together, our results are the first to demonstrate the importance of ARC protein in the inhibition of both the extrinsic and intrinsic pathways of apoptosis in RCCs. In this context, ARC cooperates with anti-apoptotic Bcl-2 family members to exert its strong anti-apoptotic effects and is therefore an important factor not only in the therapeutic resistance but also in future therapy strategies (i.e., Bcl-2 inhibitors) in RCC. In sum, targeting of ARC may enhance the therapeutic response in combination therapy protocols.

Comparison of DNA Damage and Apoptosis Induced By Silver Nanoparticle-containing Dressing Materials During Wound Healing.

PubMed

Choi, Young Suk; Gwak, Heui-Chul; Park, Jae Keun; Lim, Ji Yun; Yeo, Eui Dong; Park, Eunseok; Kim, Junyong; Lee, Young Koo

2018-04-13

Silver nanoparticle (AgNP)-containing dressings are used worldwide for the treatment of wounds; however, many studies have indicated that AgNPs are toxic to humans and cause cell death, primarily via apoptosis. In this study, the investigators compare the apoptotic effects of various AgNP dressing materials, with the hypothesis that nanosilver would be less toxic than ionic silver. For the in vivo experiments, Sprague-Dawley (SD) and streptozotocin (STZ)-induced diabetic rats were treated with 5 dressing materials: Aquacel Ag (product A, silver ion; ConvaTec, Berkshire, UK), Acticoat (product B, AgNP; Smith & Nephew, Fort Worth, TX), Medifoam Silver (product C, silver ion; Genewel Science Co Ltd, Seongnam, South Korea), PolyMem Silver (product D, AgNP; Ferris Mfg Corp, Fort Worth, TX), and Vaseline-impregnated dressing gauze (control; Unilever, London, UK). All treatments were applied 3 times per week. After 14 days of treatment, the SD and STZ rats were euthanized, and wound samples were examined for apoptosis. The analysis included immunohistochemistry, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, Western blotting, and reverse transcription polymerase chain reaction for a semiquantitative evaluation of apoptosis. The AgNP-containing dressing materials were more cytotoxic than the silver dressings. Compared with the AgNP dressing materials, no significant levels of apoptotic factors were observed in the silver dressing-treated wounds. The TUNEL staining showed that product C-dressed wounds contained the most apoptotic cells, while some apoptotic cells were observed in product B-dressed wounds. Moreover, apoptotic gene expression was altered, including a decline in B-cell lymphoma-2 and activation of caspase-3. This was most evident in wounds treated with product C. Interestingly, apoptotic gene expression was not induced in product A-treated wounds. Finally, product D had a relatively lower silver concentration and was less toxic than products A-C. Dressing materials containing AgNP have an antimicrobial effect. However, the authors observed that some AgNP dressings induced DNA damage and apoptosis. Although AgNP dressings did not cause significant acute apoptotic effects, they should be examined for cytotoxic effects in chronic wounds and should be used with caution when treating chronic wounds and those with low bacteria counts.

Inside HDAC with HDAC inhibitors.

PubMed

Bertrand, Philippe

2010-06-01

Histone deacetylase inhibitors are a large group of diverse molecules intrinsically able to inhibit cell proliferation in various cancer cell lines. Their apoptotic effects have been linked to the modulation in the expression of several regulatory tumor suppressor genes caused by the modified status of histone acetylation, a key event in chromatin remodelling. As the initial histone deacetylase activity of HDAC has been extended to other proteins, the possible other biological mechanisms modified by HDAC inhibitor treatments are still to be clarified. The need for HDAC isoform selective inhibitors is an important issue to serve this goal. This review discusses the approaches proposed by several research groups working on the synthesis of HDAC inhibitors, based on modelling studies and the way these findings were used to obtain new HDAC inhibitors with possible isoform selectivity. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

Brain-derived neurotrophic factor reduces inflammation and hippocampal apoptosis in experimental Streptococcus pneumoniae meningitis.

PubMed

Xu, Danfeng; Lian, Di; Wu, Jing; Liu, Ying; Zhu, Mingjie; Sun, Jiaming; He, Dake; Li, Ling

2017-08-04

Streptococcus pneumoniae meningitis is a serious inflammatory disease of the central nervous system (CNS) and is associated with high morbidity and mortality rates. The inflammatory processes initiated by recognition of bacterial components contribute to apoptosis in the hippocampal dentate gyrus. Brain-derived neurotrophic factor (BDNF) has long been recommended for the treatment of CNS diseases due to its powerful neuro-survival properties, as well as its recently reported anti-inflammatory and anti-apoptotic effects in vitro and in vivo. In this study, we investigated the effects of BDNF-related signaling on the inflammatory response and hippocampal apoptosis in experimental models of pneumococcal meningitis. Pretreatment with exogenous BDNF or the tropomyosin-receptor kinase B (TrkB) inhibitor k252a was performed to assess the activation or inhibition of the BDNF/TrkB-signaling axis prior to intracisternal infection with live S. pneumoniae. At 24 h post-infection, rats were assessed for clinical severity and sacrificed to harvest the brains. Paraffin-embedded brain sections underwent hematoxylin and eosin staining to evaluate pathological severity, and cytokine and chemokine levels in the hippocampus and cortex were evaluated by enzyme-linked immunosorbent assay. Additionally, apoptotic neurons were detected in the hippocampal dentate gyrus by terminal deoxynucleotidyl transferase dUTP-nick-end labeling, key molecules associated with the related signaling pathway were analyzed by real-time polymerase chain reaction and western blot, and the DNA-binding activity of nuclear factor kappa B (NF-κB) was measured by electrophoretic mobility shift assay. Rats administered BDNF exhibited reduced clinical impairment, pathological severity, and hippocampal apoptosis. Furthermore, BDNF pretreatment suppressed the expression of inflammatory factors, including tumor necrosis factor α, interleukin (IL)-1β, and IL-6, and increased the expression of the anti-inflammatory factor IL-10. Moreover, BDNF pretreatment increased TrkB expression, activated downstream phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling, and inhibited the myeloid differentiation primary response gene 88 (MyD88)/NF-κB-signaling pathway. These data suggested that BDNF administration exerted anti-inflammatory and anti-apoptotic effects on an experimental pneumococcal meningitis model via modulation of MyD88/NF-κB- and PI3K/AKT-signaling pathways. Our results indicated that treatment with exogenous BDNF might constitute a potential therapeutic strategy for the treatment of bacterial meningitis.

Chronic MDMA induces neurochemical changes in the hippocampus of adolescent and young adult rats: Down-regulation of apoptotic markers.

PubMed

García-Cabrerizo, Rubén; García-Fuster, M Julia

2015-07-01

While hippocampus is a brain region particularly susceptible to the effects of MDMA, the cellular and molecular changes induced by MDMA are still to be fully elucidated, being the dosage regimen, the species and the developmental stage under study great variables. This study compared the effects of one and four days of MDMA administration following a binge paradigm (3×5 mg/kg, i.p., every 2 h) on inducing hippocampal neurochemical changes in adolescent (PND 37) and young adult (PND 58) rats. The results showed that chronic MDMA caused hippocampal protein deficits in adolescent and young adult rats at different levels: (1) impaired serotonergic (5-HT2A and 5-HT2C post-synaptic receptors) and GABAergic (GAD2 enzyme) signaling, and (2) decreased structural cytoskeletal neurofilament proteins (NF-H, NF-M and NF-L). Interestingly, these effects were not accompanied by an increase in apoptotic markers. In fact, chronic MDMA inhibited proteins of the apoptotic pathway (i.e., pro-apoptotic FADD, Bax and cytochrome c) leading to an inhibition of cell death markers (i.e., p-JNK1/2, cleavage of PARP-1) and suggesting regulatory mechanisms in response to the neurochemical changes caused by the drug. The data, together with the observed lack of GFAP activation, support the view that chronic MDMA effects, regardless of the rat developmental age, extends beyond neurotransmitter systems to impair other hippocampal structural cell markers. Interestingly, inhibitory changes in proteins from the apoptotic pathway might be taking place to overcome the protein deficits caused by MDMA. Copyright © 2015 Elsevier Inc. All rights reserved.

Akt-mediated anti-apoptotic effects of substance P in Anti-Fas-induced apoptosis of human tenocytes

PubMed Central

Backman, Ludvig J; Danielson, Patrik

2013-01-01

Substance P (SP) and its receptor, the neurokinin-1 receptor (NK-1 R), are expressed by human tenocytes, and they are both up-regulated in cases of tendinosis, a condition associated with excessive apoptosis. It is known that SP can phosphorylate/activate the protein kinase Akt, which has anti-apoptotic effects. This mechanism has not been studied for tenocytes. The aims of this study were to investigate if Anti-Fas treatment is a good apoptosis model for human tenocytes in vitro, if SP protects from Anti-Fas-induced apoptosis, and by which mechanisms SP mediates an anti-apoptotic response. Anti-Fas treatment resulted in a time- and dose-dependent release of lactate dehydrogenase (LDH), i.e. induction of cell death, and SP dose-dependently reduced the Anti-Fas-induced cell death through a NK-1 R specific pathway. The same trend was seen for the TUNEL assay, i.e. SP reduced Anti-Fas-induced apoptosis via NK-1 R. In addition, it was shown that SP reduces Anti-Fas-induced decrease in cell viability as shown with crystal violet assay. Protein analysis using Western blot confirmed that Anti-Fas induces cleavage/activation of caspase-3 and cleavage of PARP; both of which were inhibited by SP via NK-1 R. Finally, SP treatment resulted in phosphorylation/activation of Akt as shown with Western blot, and it was confirmed that the anti-apoptotic effect of SP was, at least partly, induced through the Akt-dependent pathway. In conclusion, we show that SP reduces Anti-Fas-induced apoptosis in human tenocytes and that this anti-apoptotic effect of SP is mediated through NK-1 R and Akt-specific pathways. PMID:23577779

Methotrexate induces poly(ADP-ribose) polymerase-dependent, caspase 3-independent apoptosis in subsets of proliferating CD4+ T cells.

PubMed

Nielsen, C H; Albertsen, L; Bendtzen, K; Baslund, B

2007-05-01

The mechanism of action of methotrexate (MTX) in autoimmune diseases (AID) is unclear. A pro-apoptotic effect has been demonstrated in mitogen-stimulated peripheral blood mononuclear cells (PBMC), but studies employing conventional antigens have disputed a pro-apoptotic effect. CD4+ T helper (Th) cells play a significant role in most AID. We therefore examined directly, by flow cytometry, the uptake of MTX by the T helper (Th) cells stimulated for 6 days with Candida albicans (CA) or tetanus toxoid (TT), and its consequences with respect to induction of apoptosis. While none of the resting Th cells took up MTX, nearly all the dividing Th cells did, and this abrogated further cell division. Among dividing Th cells, MTX induced an approximately sixfold increase over baseline levels in the proportion of apoptotic cells. This proportion could be reverted to baseline by the addition of folic acid. Exposure of CA-stimulated PBMC to MTX significantly increased their level of cleaved poly(ADP-ribose) polymerase (PARP), and a similar tendency was observed in TT-stimulated cells. Unlike CA and TT, the mitogen phytohaemagglutinin (PHA) induced proliferation of both CD4- and CD4+ T cells, and induced apoptosis in both undivided and divided Th cells. PHA-induced apoptosis involved activation of caspase-3 and the anti-apoptotic protein Bcl-2 in addition to PARP cleavage, suggesting that PHA induces apoptosis via different pathways than CA and TT. We suggest that the latter are more representative of stimulation with self-antigens in AID, and that a pro-apoptotic effect of MTX on self-antigen-stimulated Th cells contributes to the effect of MTX in the treatment of AID.

A bloody mess: dendritic cells use hemophagocytosis to regulate viral inflammation.

PubMed

Miller, Elizabeth; Bhardwaj, Nina

2013-09-19

Previous studies have highlighted the immune-dampening effects of apoptotic cell uptake by phagocytes. Ohyagi et al. (2013) expose a unique mechanism of immune regulation during viral infection, which is mediated through phagocytosis of apoptotic red cells by dendritic cells. Copyright © 2013 Elsevier Inc. All rights reserved.

Naringin ameliorates acetic acid induced colitis through modulation of endogenous oxido-nitrosative balance and DNA damage in rats

PubMed Central

Kumar, Venkatashivam Shiva; Rajmane, Anuchandra Ramchandra; Adil, Mohammad; Kandhare, Amit Dattatraya; Ghosh, Pinaki; Bodhankar, Subhash Laxman

2014-01-01

The aim of this study was to evaluate the effect of naringin on experimentally induced inflammatory bowel disease in rats. Naringin (20, 40 and 80 mg/kg) was given orally for 7 days to Wistar rats before induction of colitis by intrarectal instillation of 2 mL of 4% (v/v) acetic acid solution. The degree of colonic mucosal damage was analyzed by examining mucosal damage, ulcer area, ulcer index and stool consistency. Intrarectal administration of 4% acetic acid resulted in significant modulation of serum alkaline phosphatase, lactate dehydrogenase, superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA) and myeloperoxidase (MPO) content along with colonic nitric oxide (NO), xanthine oxidase (XO) level and protein carbonyl content in the colonic tissue as well as in blood. Naringin (40 and 80 mg/kg) exerted a dose dependent (P < 0.05) ameliorative effect, as it significantly increased hematological parameter as well as colonic SOD and GSH. There was a significant (P < 0.05) and dose dependant inhibition of macroscopical score, ulcer area along with colonic MDA, MPO activity by the 7 days of pretreatment of naringin (40 and 80 mg/kg). Biochemical studies revealed a significant (P < 0.05) dose dependant inhibition in serum alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) levels by pretreatment of naringin. Increased levels of colonic NO, XO, protein carbonyl content and DNA damage were also significantly decreased by naringin pretreatment. The findings of the present investigation propose that naringin has an anti-inflammatory, anti-oxidant and anti-apoptotic potential effect at colorectal sites as it modulates the production and expression of oxidative mediators such as MDA, MPO, NO and XO, thus reducing DNA damage. PMID:24683411

Antiproliferative activity and induction of apoptotic by ethanolic extract of Alpinia galanga rhizhome in human breast carcinoma cell line.

PubMed

Samarghandian, Saeed; Hadjzadeh, Mousa-Al-Reza; Afshari, Jalil Tavakkol; Hosseini, Mohadeseh

2014-06-17

We investigated the potential of galangal rhizomes to induce cytotoxic and apoptotic effects in the cultured human breast carcinoma cell line, (MCF-7) in compare with the non-malignant (MRC-5) cells. Both cells were cultured in DMEM medium and treated with galangal rhizomes for three consecutive days. The percentage of apoptotic cells was determined by flow cytometry using Annexin-V fluorescein isothiocyanate. The results showed that the ethanolic extract of galangal rhizomes decreased cell viability in the malignant cells as a concentration- and time- dependent manner. The IC50 values against MCF-7 were determined at 400.0 ± 11.7 and 170.0 ± 5.9 μg/ml after 48 and 72 h respectively. The morphology of MCF-7 cells treated with the ethanolic extract confirmed the cell proliferation assay results. Alpinia galanga induced apoptosis in MCF-7 cells, as determined by flow cytometry. We concluded that the extract of Alpinia galanga exerts pro-apoptotic effects in a breast cancer-derived cell line and could be considered as a potential chemotherapeutic agent in breast cancer.

Hyperforin Inhibits Cell Growth by Inducing Intrinsic and Extrinsic Apoptotic Pathways in Hepatocellular Carcinoma Cells.

PubMed

Chiang, I-Tsang; Chen, Wei-Ting; Tseng, Chih-Wei; Chen, Yen-Chung; Kuo, Yu-Cheng; Chen, Bi-Jhih; Weng, Mao-Chi; Lin, Hwai-Jeng; Wang, Wei-Shu

2017-01-01

The aim of the present study was to investigate the antitumor effect and mechanism of action of hyperforin in hepatocellular carcinoma (HCC) SK-Hep1 cells in vitro. Cells were treated with different concentrations of hyperforin for different periods of time. Effects of hyperforin on cell viability, apoptosis signaling, and expression of anti-apoptotic and proliferative proteins [cellular FLICE-like inhibitory protein (c-FLIP), X-linked inhibitor of apoptosis protein (XIAP), myeloid cell leukemia 1(MCL1), and cyclin-D1] were investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, and western blotting. Hyperforin significantly inhibited cell viability and expression of anti-apoptotic and proliferative proteins. We also found that hyperforin significantly induced accumulation of cells in sub-G 1 phase, loss of mitochondrial membrane potential, and increased levels of active caspase-3, and caspase-8. Taken together, our findings indicate that hyperforin triggers inhibition of tumor cell growth by inducing intrinsic and extrinsic apoptotic pathways in HCC SK-Hep1 cells. Copyright© 2017 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

THE CONTRIBUTION OF TYRO3 FAMILY RECEPTOR TYROSINE KINASES TO THE HETEROGENEITY OF APOPTOTIC CELL UPTAKE BY MONONUCLEAR PHAGOCYTES

PubMed Central

Curtis, Jeffrey L.; Todt, Jill C.; Hu, Bin; Osterholzer, John J.; Freeman, Christine M.

2014-01-01

Mononuclear phagocytes comprise a mobile, broadly dispersed and highly adaptable system that lies at the very epicenter of host defense against pathogens and the interplay of the innate and adaptive arms of immunity. Understanding the molecular mechanisms that control the response of mononuclear phagocytes to apoptotic cells and the anti-inflammatory consequences of that response is an important goal with implications for multiple areas of biomedical sciences. This review details current understanding of the heterogeneity of apoptotic cell uptake by different members of the mononuclear phagocyte family in humans and mice. It also recounts the unique role of the Tyro3 family of receptor tyrosine kinases, best characterized for Mertk, in the signal transduction leading both to apoptotic cell ingestion and the anti-inflammatory effects that result. PMID:19273223

The pro-apoptotic serum activity is an independent mortality predictor of patients with heart failure.

PubMed

Rössig, Lothar; Fichtlscherer, Stephan; Heeschen, Christopher; Berger, Jürgen; Dimmeler, Stefanie; Zeiher, Andreas M

2004-09-01

Systemic inflammation with elevated serum levels of circulating pro-inflammatory cytokines is a major determinant of prognosis in heart failure (HF). Since serum of patients with HF induces apoptosis of endothelial cells (EC), we aimed to determine whether the pro-apoptotic activity in the serum may predict prognosis of patients with HF. We measured the pro-apoptotic activity in the serum of 48 patients with HF of different aetiology by an ex vivo cell culture assay and subsequently monitored these patients for the single endpoint all-cause mortality. During follow-up, 16 patients died and 11 patients received a heart transplant. Survivors had a lower pro-apoptotic serum activity (P=0.007). By univariate analysis, pro-apoptotic serum activity, NYHA class, pro-BNP, low blood pressure, and creatinine levels were significantly associated with mortality. In a multivariable stepwise Cox-regression model, the pro-apoptotic serum activity (adjusted hazard ratio, HR=1.85 per %, P=0.008), elevated pro-BNP levels (HR=9.35 per log[pro-BNP], P=0.001), and low blood pressure (HR=0.96 per mmHg, P=0.041) remained as independent predictors of death. In this exploratory study, the pro-apoptotic serum capacity is independently associated with a worse prognosis in patients with HF, suggesting that the assessment of serum-induced EC apoptosis could provide an integrative estimate of the deleterious effects of various pro-inflammatory cytokines and other cytotoxic factors in HF.

The TAM-family receptor Mer mediates production of HGF through the RhoA-dependent pathway in response to apoptotic cells.

PubMed

Park, Hyun-Jung; Baen, Ji-Yeon; Lee, Ye-Ji; Choi, Youn-Hee; Kang, Jihee Lee

2012-08-01

The TAM receptor protein tyrosine kinases Tyro3, Axl, and Mer play important roles in macrophage function. We investigated the roles of the TAM receptors in mediating the induction of hepatocyte growth factor (HGF) during the interaction of macrophages with apoptotic cells. Mer-specific neutralizing antibody, small interfering RNA (siRNA), and a recombinant Mer protein (Mer/Fc) inhibited HGF mRNA and protein expression, as well as activation of RhoA, Akt, and specific mitogen-activated protein (MAP) kinases in response to apoptotic cells. Inhibition of Axl or Tyro3 with specific antibodies, siRNA, or Fc-fusion proteins did not prevent apoptotic cell-induced HGF mRNA and protein expression and did not inhibit activation of the postreceptor signaling molecules RhoA and certain MAP kinases, including extracellular signal-regulated protein kinase and c-Jun NH(2)-terminal kinase. However, Axl- and Tyro3-specific blockers did inhibit the activation of Akt and p38 MAP kinase in response to apoptotic cells. In addition, none of the TAM receptors mediated the effects of apoptotic cells on transforming growth factor-β or epidermal growth factor mRNA expression. However, they were involved in the induction of vascular endothelial growth factor mRNA expression. Our data provide evidence that when macrophages interact with apoptotic cells, only Mer of the TAM-family receptors is responsible for mediating transcriptional HGF production through a RhoA-dependent pathway.

Voltage-gated K+ channel modulators as neuroprotective agents.

PubMed

Leung, Yuk-Man

2010-05-22

A manifestation in neurodegeneration is apoptosis of neurons. Neurons undergoing apoptosis may lose a substantial amount of cytosolic K+ through a number of pathways including K+ efflux via voltage-gated K+ (Kv) channels. The consequent drop in cytosolic [K+] relieves inhibition of an array of pro-apoptotic enzymes such as caspases and nucleases. Blocking Kv channels has been known to prevent neuronal apoptosis by preventing K+ efflux. Some neural diseases such as epilepsy are caused by neuronal hyperexcitability, which eventually may lead to neuronal apoptosis. Reduction in activities of A-type Kv channels and Kv7 subfamily members is amongst the etiological causes of neuronal hyperexcitation; enhancing the opening of these channels may offer opportunities of remedy. This review discusses the potential uses of Kv channel modulators as neuroprotective drugs.

Clearance of Apoptotic Photoreceptors

PubMed Central

Hisatomi, Toshio; Sakamoto, Taiji; Sonoda, Koh-hei; Tsutsumi, Chikako; Qiao, Hong; Enaida, Hiroshi; Yamanaka, Ichiro; Kubota, Toshiaki; Ishibashi, Tatsuro; Kura, Shinobu; Susin, Santos A.; Kroemer, Guido

2003-01-01

The effective phagocytotic clearance of apoptotic debris is fundamental to the maintenance of neural tissues during apoptosis. Retinal photoreceptors undergo apoptosis after retinal detachment. Although their induction phase of apoptosis has been well discussed, their phagocytotic process remains quite unclear. We herein demonstrate that apoptotic photoreceptors are selectively eliminated from their physiological localization, the outer nuclear layer, to the subretinal space, and then phagocytosed by monocyte-derived macrophages. This could be shown by an ultrastructural and immunophenotypic analysis. Moreover, in chimera mice expressing transgenic green fluorescent protein in bone marrow-derived cells, the local infiltration of macrophages could be detected after retinal detachment-induced photoreceptor apoptosis. The local injection of an antibody blocking the phosphatidylserine receptor (PSR) or a peptide (GRGDSP)-blocking integrin αvβ3 revealed that phagocytotic clearance involves the PSR as well as integrin αvβ3 in vivo. Importantly, the level of blockade obtained with these reagents was different. Although anti-PSR increased the frequency of apoptotic cells that fail to bind to macrophages, GRGDSP prevented the engulfment (but not the recognition) of apoptotic photoreceptor cells by macrophages. To our knowledge, this is the first report describing the mechanisms through which apoptotic photoreceptors are selectively eliminated via a directional process in the subretinal space. PMID:12759244

cAMP/PKA signaling balances respiratory activity with mitochondria dependent apoptosis via transcriptional regulation

PubMed Central

2010-01-01

Background Appropriate control of mitochondrial function, morphology and biogenesis are crucial determinants of the general health of eukaryotic cells. It is therefore imperative that we understand the mechanisms that co-ordinate mitochondrial function with environmental signaling systems. The regulation of yeast mitochondrial function in response to nutritional change can be modulated by PKA activity. Unregulated PKA activity can lead to the production of mitochondria that are prone to the production of ROS, and an apoptotic form of cell death. Results We present evidence that mitochondria are sensitive to the level of cAMP/PKA signaling and can respond by modulating levels of respiratory activity or committing to self execution. The inappropriate activation of one of the yeast PKA catalytic subunits, Tpk3p, is sufficient to commit cells to an apoptotic death through transcriptional changes that promote the production of dysfunctional, ROS producing mitochondria. Our data implies that cAMP/PKA regulation of mitochondrial function that promotes apoptosis engages the function of multiple transcription factors, including HAP4, SOK2 and SCO1. Conclusions We propose that in yeast, as is the case in mammalian cells, mitochondrial function and biogenesis are controlled in response to environmental change by the concerted regulation of multiple transcription factors. The visualization of cAMP/TPK3 induced cell death within yeast colonies supports a model that PKA regulation plays a physiological role in coordinating respiratory function and cell death with nutritional status in budding yeast. PMID:21108829

Winding through the WNT pathway during cellular development and demise.

PubMed

Li, F; Chong, Z Z; Maiese, K

2006-01-01

In slightly over a period of twenty years, our comprehension of the cellular and molecular mechanisms that govern the Wnt signaling pathway continue to unfold. The Wnt proteins were initially implicated in viral carcinogenesis experiments associated with mammary tumors, but since this period investigations focusing on the Wnt pathways and their transmembrane receptors termed Frizzled have been advanced to demonstrate the critical nature of Wnt for the development of a variety of cell populations as well as the potential of the Wnt pathway to avert apoptotic injury. In particular, Wnt signaling plays a significant role in both the cardiovascular and nervous systems during embryonic cell patterning, proliferation, differentiation, and orientation. Furthermore, modulation of Wnt signaling under specific cellular influences can either promote or prevent the early and late stages of apoptotic cellular injury in neurons, endothelial cells, vascular smooth muscle cells, and cardiomyocytes. A number of downstream signal transduction pathways can mediate the biological response of the Wnt proteins that include Dishevelled, beta-catenin, intracellular calcium, protein kinase C, Akt, and glycogen synthase kinase-3beta. Interestingly, these cellular cascades of the Wnt-Frizzled pathways can participate in several neurodegenerative, vascular, and cardiac disorders and may be closely integrated with the function of trophic factors. Identification of the critical elements that modulate the Wnt-Frizzled signaling pathway should continue to unlock the potential of Wnt pathway for the development of new therapeutic options against neurodegenerative and vascular diseases.

BL-038, a Benzofuran Derivative, Induces Cell Apoptosis in Human Chondrosarcoma Cells through Reactive Oxygen Species/Mitochondrial Dysfunction and the Caspases Dependent Pathway.

PubMed

Liu, Ju-Fang; Chen, Chien-Yu; Chen, Hsien-Te; Chang, Chih-Shiang; Tang, Chih-Hsin

2016-09-07

Chondrosarcoma is a highly malignant cartilage-forming bone tumor that has the capacity to invade locally and cause distant metastasis. Moreover, chondrosarcoma is intrinsically resistant to conventional chemotherapy or radiotherapy. The novel benzofuran derivative, BL-038 (2-amino-3-(2,6-dichlorophenyl)-6-(4-methoxyphenyl)benzofuran-4-yl acetate), has been evaluated for its anticancer effects in human chondrosarcoma cells. BL-038 caused cell apoptosis in two human chondrosarcoma cell lines, JJ012 and SW1353, but not in primary chondrocytes. Treatment of chondrosarcoma with BL-038 also induced reactive oxygen species (ROS) production. Furthermore, BL-038 decreased mitochondrial membrane potential (MMP) and changed mitochondrial-related apoptosis, by downregulating the anti-apoptotic activity members (Bcl-2, Bcl-xL) and upregulating pro-apoptotic members (Bax, Bak) of the B-cell lymphoma 2 (Bcl-2) family of proteins, key regulators of the apoptotic machinery in cells. These results demonstrate that in human chondrosarcoma cells, the apoptotic and cytotoxic effects of BL-038 are mediated by the intrinsic mitochondria-mediated apoptotic pathway, which in turn causes the release of cytochrome c, the activation of caspase-9 and caspase-3, and the cleavage of poly (ADP-ribose) polymerase (PARP), to elicit apoptosis response. Our results show that the benzofuran derivative BL-038 induces apoptosis in chondrosarcoma cells.

BL-038, a Benzofuran Derivative, Induces Cell Apoptosis in Human Chondrosarcoma Cells through Reactive Oxygen Species/Mitochondrial Dysfunction and the Caspases Dependent Pathway

PubMed Central

Liu, Ju-Fang; Chen, Chien-Yu; Chen, Hsien-Te; Chang, Chih-Shiang; Tang, Chih-Hsin

2016-01-01

Chondrosarcoma is a highly malignant cartilage-forming bone tumor that has the capacity to invade locally and cause distant metastasis. Moreover, chondrosarcoma is intrinsically resistant to conventional chemotherapy or radiotherapy. The novel benzofuran derivative, BL-038 (2-amino-3-(2,6-dichlorophenyl)-6-(4-methoxyphenyl)benzofuran-4-yl acetate), has been evaluated for its anticancer effects in human chondrosarcoma cells. BL-038 caused cell apoptosis in two human chondrosarcoma cell lines, JJ012 and SW1353, but not in primary chondrocytes. Treatment of chondrosarcoma with BL-038 also induced reactive oxygen species (ROS) production. Furthermore, BL-038 decreased mitochondrial membrane potential (MMP) and changed mitochondrial-related apoptosis, by downregulating the anti-apoptotic activity members (Bcl-2, Bcl-xL) and upregulating pro-apoptotic members (Bax, Bak) of the B-cell lymphoma 2 (Bcl-2) family of proteins, key regulators of the apoptotic machinery in cells. These results demonstrate that in human chondrosarcoma cells, the apoptotic and cytotoxic effects of BL-038 are mediated by the intrinsic mitochondria-mediated apoptotic pathway, which in turn causes the release of cytochrome c, the activation of caspase-9 and caspase-3, and the cleavage of poly (ADP-ribose) polymerase (PARP), to elicit apoptosis response. Our results show that the benzofuran derivative BL-038 induces apoptosis in chondrosarcoma cells. PMID:27618007

Wogonin induces apoptosis by suppressing E6 and E7 expressions and activating intrinsic signaling pathways in HPV-16 cervical cancer cells.

PubMed

Kim, Man Sub; Bak, Yesol; Park, Yun Sun; Lee, Dong Hun; Kim, Jung Hee; Kang, Jeong Woo; Song, Hyuk-Hwan; Oh, Sei-Ryang; Yoon, Do Young

2013-08-01

Wogonin is a flavonoid compound extracted from Scutellaria baicalensis and is well known as a benzodiazepine receptor ligand with anxiolytic effects. Many recent studies have demonstrated that wogonin modulates angiogenesis, proliferation, invasion, and tumor progress in various cancer tissues. We further explored the mechanism of action of wogonin on cervical cancer cells that contain or lack human papillomavirus (HPV) DNA. Wogonin was cytotoxic to HPV 16 (+) cervical cancer cells, SiHa and CaSki, but not to HPV-negative cells. We demonstrated that wogonin induced apoptosis by suppressing the expressions of the E6 and E7 viral oncogenes in HPV-infected cervical cancer CaSki and SiHa cells. The modulation of p53 and protein retinoblastoma (pRb) were also triggered by the suppression of E6 and E7 expressions. However, p53 was not altered in HPV-negative cervical cancer C33A cells. Moreover, wogonin modulated the mitochondrial membrane potential and the expression of pro- and anti-apoptotic factors such as Bax and Bcl-2. Wogonin also provoked the cleavage of caspase-3, caspase-9, and poly ADP ribose polymerase. After transfection of siRNAs to target E6 and E7, additional restoration of p53 and pRb was not induced, but processing of caspases and PARP was increased compared with wogonin treatment alone. Together, our findings demonstrated that wogonin effectively promotes apoptosis by downregulating E6 and E7 expressions and promoting intrinsic apoptosis in human cervical cancer cells.

Oxidatively modified phosphatidylserines on the surface of apoptotic cells are essential phagocytic ‘eat-me' signals: cleavage and inhibition of phagocytosis by Lp-PLA2

PubMed Central

Tyurin, V A; Balasubramanian, K; Winnica, D; Tyurina, Y Y; Vikulina, A S; He, R R; Kapralov, A A; Macphee, C H; Kagan, V E

2014-01-01

Diversified anionic phospholipids, phosphatidylserines (PS), externalized to the surface of apoptotic cells are universal phagocytic signals. However, the role of major PS metabolites, such as peroxidized species of PS (PSox) and lyso-PS, in the clearance of apoptotic cells has not been rigorously evaluated. Here, we demonstrate that H2O2 was equally effective in inducing apoptosis and externalization of PS in naive HL60 cells and in cells enriched with oxidizable polyunsaturated species of PS (supplemented with linoleic acid (LA)). Despite this, the uptake of LA-supplemented cells by RAW264.7 and THP-1 macrophages was more than an order of magnitude more effective than that of naive cells. A similar stimulation of phagocytosis was observed with LA-enriched HL60 cells and Jurkat cells triggered to apoptosis with staurosporine. This was due to the presence of PSox on the surface of apoptotic LA-supplemented cells (but not of naive cells). This enhanced phagocytosis was dependent on activation of the intrinsic apoptotic pathway, as no stimulation of phagocytosis occurred in LA-enriched cells challenged with Fas antibody. Incubation of apoptotic cells with lipoprotein-associated phospholipase A2 (Lp-PLA2), a secreted enzyme with high specificity towards PSox, hydrolyzed peroxidized PS species in LA-supplemented cells resulting in the suppression of phagocytosis to the levels observed for naive cells. This suppression of phagocytosis by Lp-PLA2 was blocked by a selective inhibitor of Lp-PLA2, SB-435495. Screening of possible receptor candidates revealed the ability of several PS receptors and bridging proteins to recognize both PS and PSox, albeit with diverse selectivity. We conclude that PSox is an effective phagocytic ‘eat-me' signal that participates in the engulfment of cells undergoing intrinsic apoptosis. PMID:24464221

Pan-Cancer Analysis Links PARK2 to BCL-XL-Dependent Control of Apoptosis.

PubMed

Gong, Yongxing; Schumacher, Steven E; Wu, Wei H; Tang, Fanying; Beroukhim, Rameen; Chan, Timothy A

2017-02-01

Mutation of the PARK2 gene can promote both Parkinson's Disease and cancer, yet the underlying mechanisms of how PARK2 controls cellular physiology is incompletely understood. Here, we show that the PARK2 tumor suppressor controls the apoptotic regulator BCL-XL and modulates programmed cell death. Analysis of approximately 10,000 tumor genomes uncovers a striking pattern of mutual exclusivity between PARK2 genetic loss and amplification of BCL2L1, implicating these genes in a common pathway. PARK2 directly binds to and ubiquitinates BCL-XL. Inactivation of PARK2 leads to aberrant accumulation of BCL-XL both in vitro and in vivo, and cancer-specific mutations in PARK2 abrogate the ability of the ubiquitin E3 ligase to target BCL-XL for degradation. Furthermore, PARK2 modulates mitochondrial depolarization and apoptosis in a BCL-XL-dependent manner. Thus, like genes at the nodal points of growth arrest pathways such as p53, the PARK2 tumor suppressor is able to exert its antiproliferative effects by regulating both cell cycle progression and programmed cell death. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

The modulation role of serotonin in Pacific oyster Crassostrea gigas in response to air exposure.

PubMed

Dong, Wenjing; Liu, Zhaoqun; Qiu, Limei; Wang, Weilin; Song, Xiaorui; Wang, Xiudan; Li, Yiqun; Xin, Lusheng; Wang, Lingling; Song, Linsheng

2017-03-01

Serotonin, also known as 5-hydroxytryptamine (5-HT), is a critical neurotransmitter in the neuroendocrine-immune regulatory network and involved in regulation of the stress response in vertebrates and invertebrates. In the present study, serotonin was found to be widely distributed in the tissues of Pacific oyster Crassostrea gigas, including haemolymph, gonad, visceral ganglion, mantle, gill, labial palps and hepatopancreas, and its concentration increased significantly in haemolymph and mantle after the oysters were exposed to air for 1 d. The apoptosis rate of haemocytes was significantly declined after the oysters received an injection of extra serotonin, while the activity of superoxide dismutase (SOD) in haemolymph increased significantly. After the stimulation of serotonin during air exposure, the apoptosis rate of oyster haemocytes and the concentration of H 2 O 2 in haemolymph were significantly decreased, while the SOD activity was significantly elevated. Furthermore, the survival rate of oysters from 4 th to 6 th d after injection of serotonin was higher than that of FSSW group and air exposure group. The results clearly indicated that serotonin could modulate apoptotic effect and redox during air exposure to protect oysters from stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lipopolysaccharides-stimulated macrophage products enhance Withaferin A-induced apoptosis via activation of caspases and inhibition of NF-κB pathway in human cancer cells.

PubMed

Piao, Liang; Canguo, Zhao; Wenjie, Lu; Xiaoli, Cheng; Wenli, Shi; Li, Lu

2017-01-01

Macrophages, as a major cellular component in tumor microenvironment, play an important role in tumor progression. However, their roles in modulation of cytotoxic chemotherapy are still not fully understood. Here, we investigated the influence of Lipoplysaccharides (LPS)-stimulated macrophage products (LSMP) on Withaferin A (WA), a natural compound that derived from the medicinal plant Withania somnifera, as an antitumor agent in human breast cancer cells MDA-MB-231 and prostate cancer cells PC-3. Our results revealed that LSMP may enhance WA-induced apoptosis in both cell lines, the underlying mechanisms of which are closely associated with activation of caspase-8, -9 and -3, cleavage of poly ADP-ribose polymerase (PARP), as well as specifically inhibiting the translocation of nuclear factor-κB (NF-κB) and down-regulation of anti-apoptotic proteins X-linked inhibitor of apoptosis protein (XIAP) and inhibitor of apoptosis protein (cIAP1/2). These findings demonstrate that macrophages in tumor microenvironment can modulate tumor responses to chemotoxic agents, providing an effective strategy that targets macrophages to enhance the antitumor efficacy of cytotoxic chemotherapy. Copyright © 2016. Published by Elsevier Ltd.

Prenatal alcohol-induced neuroapoptosis in rat brain cerebral cortex: protective effect of folic acid and betaine.

PubMed

Sogut, Ibrahim; Uysal, Onur; Oglakci, Aysegul; Yucel, Ferruh; Kartkaya, Kazim; Kanbak, Gungor

2017-03-01

Alcohol consumption in pregnancy may cause fetal alcohol syndrome (FAS) in the infant. This study aims to investigate prenatal alcohol exposure related neuroapoptosis on the cerebral cortex tissues of newborn rats and possible neuroprotective effects of betaine, folic acid, and combined therapy. Pregnant rats were divided into five experimental groups: control, ethanol, ethanol + betaine, ethanol + folic acid, and ethanol + betaine + folic acid combined therapy groups. We measured cytochrome c release, caspase-3, calpain and cathepsin B and L. enzyme activities. In order to observe apoptotic cells in the early stages, TUNEL method was chosen together with histologic methods such as assessing the diameters of the apoptotic cells, their distribution in unit volume and volume proportion of cortical intact neuron nuclei. Calpain, caspase-3 activities, and cytochrome c levels were significantly increased in alcohol group while cathepsin B and L. activities were also found to be elevated albeit not statistically significant. These increases were significantly reversed by folic acid and betaine + folic acid treatments. While ethanol increased the number of apoptotic cells, this increase was prevented in ethanol + betaine and ethanol + betaine + folic acid groups. Morphometric examination showed that the mean diameter of apoptotic cells was increased with ethanol administration while this increase was reduced by betaine and betaine + folic acid treatments. We observed that ethanol is capable of triggering apoptotic cell death in the newborn rat brains. Furthermore, folic acid, betaine, and combined therapy of these supplements may reduce neuroapoptosis related to prenatal alcohol consumption, and might be effective on preventing fetal alcohol syndrome in infants.

Continued clearance of apoptotic cells critically depends on the phagocyte Ucp2 protein

PubMed Central

Park, Daeho; Han, Claudia; Elliott, Michael R.; Kinchen, Jason M.; Trampont, Paul C.; Das, Soumita; Collins, Sheila; Lysiak, Jeffrey J.; Hoehn, Kyle L.; Ravichandran, Kodi S.

2012-01-01

Rapid and efficient removal of apoptotic cells by phagocytes plays a key role during development, tissue homeostasis, and in controlling immune responses1–5. An important feature of efficient clearance is the capacity of a single phagocyte to ingest multiple apoptotic cells successively, and to process the increased load of corpse-derived cellular material6–9. However, factors that influence sustained phagocytic capacity or how they in turn influence continued clearance by phagocytes are not known. Here we identify that the ability of a phagocyte to control its mitochondrial membrane potential is a critical factor in the capacity of a phagocyte to engulf apoptotic cells. Changing the phagocyte mitochondrial membrane potential (genetically or pharmacologically) significantly affected phagocytosis, with lower potential enhancing engulfment and higher membrane potential inhibiting uptake. We then identified that Ucp2, a mitochondrial membrane protein that acts to lower the mitochondrial membrane potential10–12, is upregulated in phagocytes engulfing apoptotic cells (but not synthetic targets, bacteria, or yeast). Loss of Ucp2 limited the capacity of phagocytes to continually ingest apoptotic cells, while overexpression of Ucp2 increased the capacity for engulfment and the ability to engulf multiple apoptotic cells. Mutational and pharmacological inhibition of Ucp2 uncoupling activity reversed the positive effect of Ucp2 on engulfment capacity, suggesting a direct role for Ucp2-mediated mitochondrial function in phagocytosis. Macrophages from Ucp2-deficient mice13, 14 were impaired in their capacity to engulf apoptotic cells in vitro, and Ucp2-deficient mice displayed profound in vivo defects in clearing dying cells in the thymus and the testes. Collectively, these data suggest that phagocytes alter the mitochondrial membrane potential during engulfment to regulate uptake of sequential apoptotic cells, and that Ucp2 is a key molecular determinant of this step in vivo. Since Ucp2 function has also been linked to metabolic diseases and atherosclerosis14–16, these data identifying a new role for Ucp2 in regulating apoptotic cell clearance may provide additional insights toward understanding the complex etiology and pathogenesis of these diseases. PMID:21857682

Untangling the Roles of Anti-Apoptosis in Regulating Programmed Cell Death using Humanized Yeast Cells

PubMed Central

Clapp, Caitlin; Portt, Liam; Khoury, Chamel; Sheibani, Sara; Eid, Rawan; Greenwood, Matthew; Vali, Hojatollah; Mandato, Craig A.; Greenwood, Michael T.

2012-01-01

Genetically programmed cell death (PCD) mechanisms, including apoptosis, are important for the survival of metazoans since it allows, among things, the removal of damaged cells that interfere with normal function. Cell death due to PCD is observed in normal processes such as aging and in a number of pathophysiologies including hypoxia (common causes of heart attacks and strokes) and subsequent tissue reperfusion. Conversely, the loss of normal apoptotic responses is associated with the development of tumors. So far, limited success in preventing unwanted PCD has been reported with current therapeutic approaches despite the fact that inhibitors of key apoptotic inducers such as caspases have been developed. Alternative approaches have focused on mimicking anti-apoptotic processes observed in cells displaying increased resistance to apoptotic stimuli. Hormesis and pre-conditioning are commonly observed cellular strategies where sub-lethal levels of pro-apoptotic stimuli lead to increased resistance to higher or lethal levels of stress. Increased expression of anti-apoptotic sequences is a common mechanism mediating these protective effects. The relevance of the latter observation is exemplified by the observation that transgenic mice overexpressing anti-apoptotic genes show significant reductions in tissue damage following ischemia. Thus strategies aimed at increasing the levels of anti-apoptotic proteins, using gene therapy or cell penetrating recombinant proteins are being evaluated as novel therapeutics to decrease cell death following acute periods of cell death inducing stress. In spite of its functional and therapeutic importance, more is known regarding the processes involved in apoptosis than anti-apoptosis. The genetically tractable yeast Saccharomyces cerevisiae has emerged as an exceptional model to study multiple aspects of PCD including the mitochondrial mediated apoptosis observed in metazoans. To increase our knowledge of the process of anti-apoptosis, we screened a human heart cDNA expression library in yeast cells undergoing PCD due to the conditional expression of a mammalian pro-apoptotic Bax cDNA. Analysis of the multiple Bax suppressors identified revealed several previously known as well as a large number of clones representing potential novel anti-apoptotic sequences. The focus of this review is to report on recent achievements in the use of humanized yeast in genetic screens to identify novel stress-induced PCD suppressors, supporting the use of yeast as a unicellular model organism to elucidate anti-apoptotic and cell survival mechanisms. PMID:22708116

Anti-apoptotic effect of esculin on dopamine-induced cytotoxicity in the human neuroblastoma SH-SY5Y cell line.

PubMed

Zhao, Da-Long; Zou, Li-Bo; Lin, Sheng; Shi, Jian-Gong; Zhu, Hai-Bo

2007-11-01

Dopamine (DA), as a neurotoxin, can elicit severe Parkinson's disease-like syndrome by elevating intracellular reactive oxygen species (ROS) levels and apoptotic activity. In this study, we examined the effect of esculin, which was extracted from Fraxinus sielboldiana blume, on DA-induced cytotoxicity and the underlying mechanism in human neuroblastoma SH-SY5Y cells. Our results suggest that the protective effects of esculin (10(-7), 10(-6) and 10(-5) M) on DA-induced cytotoxicity may be ascribed to its anti-oxidative properties by reducing ROS level, and its anti-apoptotic effect via protecting mitochondrion membrane potential (DeltaPsim), enhancing superoxide dismutaese (SOD) activity and reduced glutathione (GSH) levels, and regulating P53, Bax and Bcl-2 expression. In addition, esculin inhibited the release of cytochrome c and apoptosis-inducing factor (AIF), and the protein expression of activated caspase 3. These data indicate that esculin may provide a useful therapeutic strategy for the treatment of progressive neurodegenerative diseases such as Parkinson's disease (PD).

Celecoxib prevents colitis associated colon carcinogenesis: an upregulation of apoptosis.

PubMed

Setia, Shruti; Nehru, Bimla; Sanyal, Sankar N

2014-12-01

Uncontrolled cell proliferation and suppressed apoptosis are the critical events transforming a normal cell to a cancerous one wherein the inflammatory microenvironment supports this oncogenic transformation. The process of colon carcinogenesis may be aggravated in chronic inflammatory conditions such as ulcerative colitis where non-steroidal anti-inflammatory drugs (NSAIDs) may effectively prevent the cellular and molecular events. Western blots and immunofluorescent analysis of DNA mismatch repair enzymes, cell cycle regulators and pro- and anti-apoptotic proteins were performed in dextran sulfate sodium (DSS)-induced ulcerative colitis and 1,2-dimethyl benz(a)anthracene (DMH)-induced colon cancer. Also, apoptotic studies were done in isolated colonocytes using fluorescent staining and in paraffin sections using TUNEL assay. An upregulation of cell cycle regulators: cyclin D1/cdk4 and cyclin E/cdk2 and anti-apoptotic Bcl-2, along with the suppression of DNA repair enzymes: MLH1 and MSH2; tumour suppressors: p53, p21and Rb and pro-apoptotic proteins: Bax and Bad were observed in the DSS, DMH and DSS+DMH groups. Proliferating cell nuclear antigen (PCNA) was also overexpressed in these groups. The ultimate executioner of the apoptotic pathway; caspase-3, was suppressed in these groups. Apoptotic studies in colonocytes and paraffin sections revealed suppressed apoptosis in these groups. These effects were corrected with the administration of a second generation NSAID, celecoxib along with the treatment of DSS and DMH. The chemopreventive action of celecoxib in colitis mediated colon carcinogenesis may include the regulation of DNA mismatch repair enzymes, cell cycle check points, cell proliferation and apoptosis. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Phenethyl Isothiocyanate Induces Apoptotic Cell Death Through the Mitochondria-dependent Pathway in Gefitinib-resistant NCI-H460 Human Lung Cancer Cells In Vitro.

PubMed

Hsia, Te-Chun; Huang, Yi-Ping; Jiang, Yi-Wen; Chen, Hsin-Yu; Cheng, Zheng-Yu; Hsiao, Yung-Ting; Chen, Cheng-Yen; Peng, Shu-Fen; Chueh, Fu-Shin; Chou, Yu-Cheng; Chung, Jing-Gung

2018-04-01

Some lung cancer patients treated with gefitinib develop resistance to this drug resulting in unsatisfactory treatment outcomes. Phenethyl isothiocyanate (PEITC), present in our common cruciferous vegetables, exhibits anticancer activities in many human cancer cell lines. Currently, there is no available information on the possible modification of gefitinib resistance of lung cancer in vitro by PEITC. Thus, the effects of PEITC on gefitinib resistant lung cancer NCI-H460 cells were investigated in vitro. The total cell viability, apoptotic cell death, production of reactive oxygen species (ROS) and Ca 2+ , levels of mitochondria membrane potential (ΔΨ m ) and caspase-3, -8 and -9 activities were measured by flow cytometry assay. PEITC induced chromatin condensation was examined by DAPI staining. PEITC-induced cell morphological changes, decreased total viable cell number and induced apoptotic cell death in NCI-H460 and NCI-H460/G cells. PEITC decreased ROS production in NCI-H460 cells, but increased production in NCI-H460/G cells. PEITC increased Ca 2+ production, decreased the levels of ΔΨ m and increased caspase-3, -8 and -9 activities in both NCI-H460 and NCI-H460/G cells. Western blotting was used to examine the effect of apoptotic cell death associated protein expression in NCI-H460 NCI-H460/G cells after exposure to PEITC. Results showed that PEITC increased expression of cleaved caspase-3, PARP, GADD153, Endo G and pro-apoptotic protein Bax in NCI-H460/G cells. Based on these results, we suggest that PEITC induces apoptotic cell death via the caspase- and mitochondria-dependent pathway in NCI-H460/G cells. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Inhibition of autophagy enhances DENSpm-induced apoptosis in human colon cancer cells in a p53 independent manner.

PubMed

Gurkan, Ajda Coker; Arisan, Elif Damla; Yerlikaya, Pinar Obakan; Ilhan, Halime; Unsal, Narcin Palavan

2018-06-01

One of the recently developed polyamine (PA) analogues, N 1 ,N 11 -diethylnorspermine (DENSpm), has been found to act as an apoptotic inducer in melanoma, breast, prostate and colon cancer cells. Also, its potential to induce autophagy has been established. Unfolded protein responses and starvation of amino acids are known to trigger autophagy. As yet, however, the molecular mechanism underlying PA deficiency-induced autophagy is not fully clarified. Here, we aimed to determine the apoptotic effect of DENSpm after autophagy inhibition by 3-methyladenine (3-MA) or siRNA-mediated Beclin-1 silencing in colon cancer cells. The apoptotic effects of DENSpm after 3-MA treatment or Beclin-1 silencing were determined by PI and AnnexinV/PI staining in conjunction with flow cytometry. Intracellular PA levels were measured by HPLC, whereas autophagy and the expression profiles of PA key players were determined in HCT116, SW480 and HT29 colon cancer cells by Western blotting. We found that DENSpm-induced autophagy was inhibited by 3-MA treatment and Beclin-1 silencing, and that apoptotic cell death was increased by PA depletion and spermidine/spermine N 1 -acetyltransferase (SSAT) upregulation. We also found that autophagy inhibition led to DENSpm-induced apoptosis through Atg5 down-regulation, p62 degradation and LC3 lipidation in both HCT116 and SW480 cells. p53 deficiency did not alter the response of the colon cancer cells to DENSpm-induced apoptotic cell death under autophagy suppression conditions. From our results we conclude that DENSpm-induced apoptotic cell death is increased when autophagy is inhibited by 3-MA or Beclin-1 siRNA through PA depletion and PA catabolic activation in colon cancer cells, regardless p53 mutation status.

Inhibition of heme oxygenase-1 enhances the cytotoxic effect of gemcitabine in urothelial cancer cells.

PubMed

Miyake, Makito; Fujimoto, Kiyohide; Anai, Satoshi; Ohnishi, Sayuri; Nakai, Yasushi; Inoue, Takeshi; Matsumura, Yoshiaki; Tomioka, Atsushi; Ikeda, Tomohiro; Okajima, Eijiro; Tanaka, Nobumichi; Hirao, Yoshihiko

2010-06-01

Elevated heme oxygenase-1 (HO-1) is associated with resistance to chemo- and radiotherapy through anti-apoptotic function. The present study evaluated whether the HO-1 inhibitor, zinc protoporphyrin IX (ZnPP), enhances the cytotoxic effect of gemcitabine in urothelial carcinoma (UC). The in vitro cytotoxic effect of combination treatment of gemcitabine and ZnPP on UC cells was examined. The in vivo growth inhibitory effects of intraperitoneal administration of gemcitabine and/or ZnPP on mouse subcutaneous tumours were examined. The apoptotic changes were analysed with the detection of DNA fragmentation and cleaved caspase-3. HO-1 was up-regulated by both gemcitabine and irradiation treatment in vitro. ZnPP sensitised the UC cells to both therapies. Enhanced apoptosis was induced by the ZnPP combined with gemicitabine. ZnPP enhanced the antitumour effect of gemcitabine in vivo along with decreased numbers of proliferating cells and increased numbers of apoptotic cells. These findings suggest that ZnPP combined with gemcitabine or irradiation therapy may be an effective therapeutic modality for UC patients.

Using animal models to evaluate the functional consequences of anesthesia during early neurodevelopment.

PubMed

Maloney, Susan E; Creeley, Catherine E; Hartman, Richard E; Yuede, Carla M; Zorumski, Charles F; Jevtovic-Todorovic, Vesna; Dikranian, Krikor; Noguchi, Kevin K; Farber, Nuri B; Wozniak, David F

2018-03-14

Fifteen years ago Olney and colleagues began using animal models to evaluate the effects of anesthetic and sedative agents (ASAs) on neurodevelopment. The results from ongoing studies indicate that, under certain conditions, exposure to these drugs during development induces an acute elevated apoptotic neurodegenerative response in the brain and long-term functional impairments. These animal models have played a significant role in bringing attention to the possible adverse effects of exposing the developing brain to ASAs when few concerns had been raised previously in the medical community. The apoptotic degenerative response resulting from neonatal exposure to ASAs has been replicated in many studies in both rodents and non-human primates, suggesting that a similar effect may occur in humans. In both rodents and non-human primates, significantly increased levels of apoptotic degeneration are often associated with functional impairments later in life. However, behavioral deficits following developmental ASA exposure have not been consistently reported even when significantly elevated levels of apoptotic degeneration have been documented in animal models. In the present work, we review this literature and propose a rodent model for assessing potential functional deficits following neonatal ASA exposure with special reference to experimental design and procedural issues. Our intent is to improve test sensitivity and replicability for detecting subtle behavioral effects, and thus enhance the translational significance of ASA models. Copyright © 2018 Elsevier Inc. All rights reserved.

Reactive oxygen species are key mediators of the nitric oxide apoptotic pathway in anterior pituitary cells.

PubMed

Machiavelli, Leticia I; Poliandri, Ariel H; Quinteros, Fernanda A; Cabilla, Jimena P; Duvilanski, Beatriz H

2007-03-01

We previously showed that long-term exposure of anterior pituitary cells to nitric oxide (NO) induces apoptosis. The intracellular signals underlying this effect remained unclear. In this study, we searched for possible mechanisms involved in the early stages of the NO apoptotic cascade. Caspase 3 was activated by NO with no apparent disruption of mitochondrial membrane potential. NO caused a rapid increase of reactive oxygen species (ROS), and this increase seems to be dependent of mitochondrial electron transport chain. The antioxidant N-acetyl-cysteine avoided ROS increase, prevented the NO-induced caspase 3 activation, and reduced the NO apoptotic effect. Catalase was inactivated by NO, while glutathione peroxidase (GPx) activity and reduced glutathione (GSH) were not modified at first, but increased at later times of NO exposure. The increase of GSH level is important for the scavenging of the NO-induced ROS overproduction. Our results indicate that ROS have an essential role as a trigger of the NO apoptotic cascade in anterior pituitary cells. The permanent inhibition of catalase may strengthen the oxidative damage induced by NO. GPx activity and GSH level augment in response to the oxidative damage, though this increase seems not to be enough to rescue the cells from the NO effect.

Lasiodin inhibits proliferation of human nasopharyngeal carcinoma cells by simultaneous modulation of the Apaf-1/caspase, AKT/MAPK and COX-2/NF-κB signaling pathways.

PubMed

Lin, Lianzhu; Deng, Wuguo; Tian, Yun; Chen, Wangbing; Wang, Jingshu; Fu, Lingyi; Shi, Dingbo; Zhao, Mouming; Luo, Wei

2014-01-01

Rabdosia serra has been widely used for the treatment of the various human diseases. However, the antiproliferative effects and underlying mechanisms of the compounds in this herb remain largely unknown. In this study, an antiproliferative compound against human nasopharyngeal carcinoma (NPC) cells from Rabdosia serra was purified and identified as lasiodin (a diterpenoid). The treatment with lasiodin inhibited cell viability and migration. Lasiodin also mediated the cell morphology change and induced apoptosis in NPC cells. The treatment with lasiodin induced the Apaf-1 expression, triggered the cytochrome-C release, and stimulated the PARP, caspase-3 and caspase-9 cleavages, thereby activating the apoptotic pathways. The treatment with lasiodin also significantly inhibited the phosphorylations of the AKT, ERK1/2, p38 and JNK proteins. The pretreatment with the AKT or MAPK-selective inhibitors considerably blocked the lasiodin-mediated inhibition of cell proliferation. Moreover, the treatment with lasiodin inhibited the COX-2 expression, abrogated NF-κB binding to the COX-2 promoter, and promoted the NF-κB translocation from cell nuclei to cytosol. The pretreatment with a COX-2-selective inhibitor abrogated the lasiodin-induced inhibition of cell proliferation. These results indicated that lasiodin simultaneously activated the Apaf-1/caspase-dependent apoptotic pathways and suppressed the AKT/MAPK and COX-2/NF-κB signaling pathways. This study also suggested that lasiodin could be a promising natural compound for the prevention and treatment of NPC.

AMP-activated protein kinase enhances the phagocytic ability of macrophages and neutrophils

PubMed Central

Bae, Hong-Beom; Zmijewski, Jaroslaw W.; Deshane, Jessy S.; Tadie, Jean-Marc; Chaplin, David D.; Takashima, Seiji; Abraham, Edward

2011-01-01

Although AMPK plays well-established roles in the modulation of energy balance, recent studies have shown that AMPK activation has potent anti-inflammatory effects. In the present experiments, we examined the role of AMPK in phagocytosis. We found that ingestion of Escherichia coli or apoptotic cells by macrophages increased AMPK activity. AMPK activation increased the ability of neutrophils or macrophages to ingest bacteria (by 46±7.8 or 85±26%, respectively, compared to control, P<0.05) and the ability of macrophages to ingest apoptotic cells (by 21±1.4%, P<0.05 compared to control). AMPK activation resulted in cytoskeletal reorganization, including enhanced formation of actin and microtubule networks. Activation of PAK1/2 and WAVE2, which are downstream effectors of Rac1, accompanied AMPK activation. AMPK activation also induced phosphorylation of CLIP-170, a protein that participates in microtubule synthesis. The increase in phagocytosis was reversible by the specific AMPK inhibitor compound C, siRNA to AMPKα1, Rac1 inhibitors, or agents that disrupt actin or microtubule networks. In vivo, AMPK activation resulted in enhanced phagocytosis of bacteria in the lungs by 75 ± 5% vs. control (P<0.05). These results demonstrate a novel function for AMPK in enhancing the phagocytic activity of neutrophils and macrophages.—Bae, H. -B., Zmijewski, J. W., Deshane, J. S., Tadie, J. -M., Chaplin, D. D., Takashima, S., Abraham, E. AMP-activated protein kinase enhances the phagocytic ability of macrophages and neutrophils. PMID:21885655

Heme oxygenase-1 prevents hyperthyroidism induced hepatic damage via an antioxidant and antiapoptotic pathway.

PubMed

Giriş, Murat; Erbil, Yeşim; Depboylu, Bilge; Mete, Ozgür; Türkoğlu, Umit; Abbasoğlu, Semra Doğru; Uysal, Müjdat

2010-12-01

The exact pathogenesis of hepatic dysfunction in hyperthyroidism is still unknown. We aimed to investigate the pathogenesis of liver dysfunction caused by hyperthyroidism through inducing heme oxygenase-1 (HO-1) expression, which has antioxidant and anti-apoptotic properties. Rats were divided into six groups: untreated (group 1), treated with zinc protoporphyrin (ZnPP) (group 2), treated with hemin (group 3), treated with tri-iodothyronine (T3) (group 4), treated with T3 and ZnPP (group 5), and treated with T3 and hemin (group 6). After 22 d, oxidative stress and antioxidant enzymes and the expression of HO-1, mitochondrial permeability transition, cytochrome c, Bax, Bcl-2, caspase-3, caspase-8, and caspase-3 activity, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay were examined. Hyperthyroidism induced oxidative stress of liver tissue was ameliorated by HO-1 induction. Administration of hemin (HO-1 inducer) increased Bcl-2 expression. Decreased expression of cytochrome c was accompanied by a decrease in caspase-3, caspase-8, Bax expression, and caspase-3 activity. The apoptotic activity and oxidative damage were found to be increased by the administration of ZnPP (HO-1 inhibitor). Immunohistochemistry findings supported these results. HO-1 induction plays a protective role in the pathogenesis of the liver dysfunction in hyperthyroidism. This effect is dependent on modulation of the antiapoptotic and antioxidative pathways by HO-1 expression. Copyright © 2010 Elsevier Inc. All rights reserved.

A glass fiber/diethylaminoethyl double filter binding assay that measures apoptotic internucleosomal DNA fragmentation.

PubMed

Erusalimsky, J D; John, J; Hong, Y; Moore, M

1996-11-15

A filter binding assay that measures internucleosomal DNA fragmentation associated with apoptosis is described. The assay is based on a novel principle that consists of using simultaneously two kinds of glass fiber filters to harvest [3H]thymidine-prelabeled cells following their incubation with inducers of apoptosis. One filter, which is neutral, traps intact chromatin and high-molecular-weight DNA. The other filter, which is positively charged with DEAE active groups, traps low-molecular-weight DNA fragments. DNA fragmentation is quantified by measuring the radioactivity retained by each of the filters. The assay was evaluated with the histiocytic lymphoma cell line U937 and the topoisomerase inhibitors camptothecin, etoposide, and doxorubicin. These agents caused a dose-dependent decrease of radioactivity in the neutral filter and a parallel increase of radioactivity in the DEAE filter. Irradiation-induced single strand breaks and topoisomerase-mediated primary DNA damage were not detected by this method. Consistent with the detection of internucleosomal DNA fragmentation, the effects measured by this assay were prevented by the endonuclease inhibitor zinc acetate and by the metabolic inhibitor sodium azide. Results obtained using this assay were validated by observation of DNA ladders on agarose gels and by morphologic examination of apoptotic features. Evaluation of the assay in a mock screen demonstrated that the introduction of the DEAE filter increases the assay sensitivity and eliminates false positives. Thus, this assay may be used in high-throughput screening approaches to discover novel modulators of apoptosis.

Anti-apoptotic and myocardial protective effects of ethyl pyruvate after regional ischaemia/reperfusion myocardial damage in an in vivo rat model.

PubMed

Shim, Haeng Seon; Lee, Wang Gyu; Kim, Yeon A; Han, Jeong Yeol; Park, Miyeong; Song, Yun Gyu; Kim, Joon Soo; Shin, Il-Woo

2017-09-01

The integration of reactive oxygen species is strongly associated with important pathophysiological mechanisms that mediate myocardial ischaemia/reperfusion (I/R) damage. Pyruvate is an efficacious scavenger of reactive oxygen species and a previous study has shown that ethyl pyruvate (EP) has a myocardial protective effect against regional I/R damage in an in vivo rat model. The purpose of this study was to determine whether the myocardial protective effect of EP is associated with anti-apoptosis. Rats were allocated to receive EP dissolved in lactated Ringer's solution or lactated Ringer's solution alone, via intraperitoneal infusion one hour before ischaemia. They were exposed to 30 minutes of ischaemia followed by reperfusion of the left coronary artery territory over two hours. Anti-apoptotic effects were checked using several biochemical parameters after two hours of reperfusion. Apoptosis was analysed using measured caspase-3 activity, Western blotting of B-cell lymphoma 2 (Bcl-2) family protein cleaved by caspase-3, and assessment of DNA laddering patterns and the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining test. In ischaemic myocardium, EP increased Bcl-2 expression, but reduced Bcl-2-associated X protein and cleaved caspase-3 expressions. EP reduced the expression of DNA laddering and the number of myocardial I/R-damaged TUNEL-positive cells. This study demonstrated that EP has an anti-apoptotic effect after regional I/R damage in an in vivo rat heart model. The myocardial protective effect of EP may be related to its anti-apoptotic effect. Copyright: © Singapore Medical Association

Anti-apoptotic BCL-2 family proteins in acute neural injury

PubMed Central

Anilkumar, Ujval; Prehn, Jochen H. M.

2014-01-01

Cells under stress activate cell survival and cell death signaling pathways. Cell death signaling frequently converges on mitochondria, a process that is controlled by the activities of pro- and anti-apoptotic B-cell lymphoma 2 (BCL-2) proteins. In this review, we summarize current knowledge on the control of neuronal survival, development and injury by anti-apoptotic BCL-2 family proteins. We discuss overlapping and differential effects of the individual family members BCL-2, BCL-extra long (BCL-XL), myeloid cell leukemia 1 (MCL-1), and BCL2-like 2 (BCL-W) in the control of survival during development and pathophysiological processes such as trophic factor withdrawal, ischemic injury, excitotoxicity, oxidative stress and energy stress. Finally we discuss recent evidence that several anti-apoptotic BCL-2 proteins influence mitochondrial bioenergetics and control neuronal Ca2+ homeostasis independent of their classical role in cell death signaling. PMID:25324720

Anti-apoptotic BCL-2 family proteins in acute neural injury.

PubMed

Anilkumar, Ujval; Prehn, Jochen H M

2014-01-01

Cells under stress activate cell survival and cell death signaling pathways. Cell death signaling frequently converges on mitochondria, a process that is controlled by the activities of pro- and anti-apoptotic B-cell lymphoma 2 (BCL-2) proteins. In this review, we summarize current knowledge on the control of neuronal survival, development and injury by anti-apoptotic BCL-2 family proteins. We discuss overlapping and differential effects of the individual family members BCL-2, BCL-extra long (BCL-XL), myeloid cell leukemia 1 (MCL-1), and BCL2-like 2 (BCL-W) in the control of survival during development and pathophysiological processes such as trophic factor withdrawal, ischemic injury, excitotoxicity, oxidative stress and energy stress. Finally we discuss recent evidence that several anti-apoptotic BCL-2 proteins influence mitochondrial bioenergetics and control neuronal Ca(2+) homeostasis independent of their classical role in cell death signaling.

TNF-α Gene Knockout in Triple Negative Breast Cancer Cell Line Induces Apoptosis

PubMed Central

Pileczki, Valentina; Braicu, Cornelia; Gherman, Claudia D.; Berindan-Neagoe, Ioana

2013-01-01

Tumor necrosis factor alpha (TNF-α) is a pro-inflammatory cytokine involved in the promotion and progression of cancer, including triple negative breast cancer cells. Thus, there is significant interest in understanding the molecular signaling pathways that connect TNF-α with the survival of tumor cells. In our experiments, we used as an in vitro model for triple negative breast cancer the cell line Hs578T. The purpose of this study is to determine the gene expression profiling of apoptotic signaling networks after blocking TNF-α formation by using specially designed siRNA molecules to target TNF-α messenger RNA. Knockdown of TNF-α gene was associated with cell proliferation inhibition and apoptosis, as observed by monitoring the cell index using the xCELLigence RTCA System and flow cytometry. PCR array technology was used to examine the transcript levels of 84 genes involved in apoptosis. 15 genes were found to be relevant after comparing the treated group with the untreated one of which 3 were down-regulated and 12 up-regulated. The down-regulated genes are all involved in cell survival, whereas the up-regulated ones are involved in and interact with pro-apoptotic pathways. The results described here indicate that the direct target of TNF-α in the Hs578T breast cancer cell line increases the level of certain pro-apoptotic factors that modulate different cellular networks that direct the cells towards death. PMID:23263670