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Deoxynucleotidyl Transferase dUTP Nick-end Labeling (deoxynucleotidyl + transferase_dutp_nick-end_labeling)
Kinds of Deoxynucleotidyl Transferase dUTP Nick-end Labeling Selected AbstractsDehydroepiandrosterone inhibits the proliferation and induces the death of HPV-positive and HPV-negative cervical cancer cells through an androgen- and estrogen-receptor independent mechanismFEBS JOURNAL, Issue 19 2009Roma A. Girón Dehydroepiandrosterone (DHEA) has a protective role against epithelial-derived carcinomas; however, the mechanisms remain unknown. We determined the effect of DHEA on cell proliferation, the cell cycle and cell death in three cell lines derived from human uterine cervical cancers infected or not with human papilloma virus (HPV). We also determined whether DHEA effects are mediated by estrogen and androgen receptors. Proliferation of C33A (HPV-negative), CASKI (HPV16-positive) and HeLa (HPV18-positive) cells was evaluated by violet crystal staining and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) reduction. Flow cytometry was used to evaluate the phases of the cell cycle, and cell death was detected using a commercially available carboxyfluorescein apoptosis detection kit that determines caspase activation. DNA fragmentation was determined using the terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. Flutamide and ICI 182,780 were used to inhibit androgen and estrogen receptors, respectively, and letrozol was used to inhibit the conversion of DHEA to estradiol. Our results show that DHEA inhibited cell proliferation in a dose-dependent manner in the three cell lines; the DHEA IC50 doses were 50, 60 and 70 ,m for C33A, CASKI and HeLa cells, respectively. The antiproliferative effect was not abrogated by inhibitors of androgen and estrogen receptors or by an inhibitor of the conversion of testosterone to estradiol, and this effect was associated with an increase in necrotic cell death in HPV-negative cells and apoptosis in HPV-positive cells. These results suggest that DHEA strongly inhibits the proliferation of cervical cancer cells, but its effect is not mediated by androgen or estrogen receptor pathways. DHEA could therefore be used as an alternative in the treatment of cervical cancer. [source] The neuronal apoptotic death in global cerebral ischemia in gerbil: Important role for sodium channel modulator,JOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2009Manoja Kumar Brahma Abstract Global ischemia was induced in gerbil by bilateral occlusion of the common carotid arteries for 5 min. Sodium ionophore monensin or sodium channel blocker tetrodotoxin (TTX) was administered at doses of 10 ,g/kg, i.p., 30 min before ischemia induction; the dose was repeated after 22 hr. Subsequently, brain infarct occurred, determined at 24 hr after occlusion. Large, well-demarcated infarcts were observed in both hemispheres, an important observation because it critically influences the interpretation of the data. Because nitric oxide (NO) production is thought to be related to ischemic neuronal damage, we examined increases in Ca2+ influx, which lead to the activation of nitric oxide synthase (NOS). Then we evaluated the contributions of neuronal NOS, endothelial NOS, and inducible NOS to NO production in brain cryosections. The cytosolic release of apoptogenic molecules like cytochrome c and p53 were confirmed after 24 hr of reflow. TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling) labeling detected the apoptotic cells, which were confirmed in neuron-rich cell populations. After 24 hr, all the ischemic changes were amplified by monensin and significantly attenuated by TTX treatment. Additionally, the nesting behavior and histological outcomes were examined after 7 day of reflow. The neuronal damage in the hippocampal area and significant decrease in nesting scores were observed with monensin treatment and reduced by TTX pretreatment after day 7 of reflow. To our knowledge, this report is the first to highlight the involvement of the voltage-sensitive Na+ channel in possibly regulating in part NO system and apoptosis in a cytochrome c,dependent manner in global ischemia in the gerbil, and thus warrants further investigation. © 2008 Wiley-Liss, Inc. [source] A caspase inhibitor, IDN-6556, ameliorates early hepatic injury in an ex vivo rat model of warm and cold ischemia,LIVER TRANSPLANTATION, Issue 3 2007Niel C. Hoglen This study examined the efficacy of the caspase inhibitor, IDN-6556, in a rat model of liver ischemia-reperfusion injury. Livers from male Sprague-Dawley rats were reperfused for 120 minutes after 24 hours of 4°C cold storage in University of Wisconsin solution. Portal blood flow measurements estimated sinusoidal resistance, and bile production, alanine aminotransferase activities, and Suzuki scores were evaluated as parameters of hepatocyte/liver injury. Treated livers were exposed to 25 or 50 ,M of IDN-6556 in University of Wisconsin storage solution and/or the perfusate. All treatment regimens with IDN-6556 significantly improved portal blood flow measured at 120 minutes, and significant improvements were seen as early as 30 minutes when inhibitor was also present in the perfusate (P < 0.01). All treatment groups with IDN-6556 significantly increased bile production by 3-4-fold compared with controls (P < 0.01), and reductions in alanine aminotransferase activities were seen within 90 minutes of reperfusion (P < 0.05). These data were confirmed by improved Suzuki scores (less sinusoidal congestion, necrosis, and vacuolization) in all treated groups. Livers from the IDN-6556,treated groups had markedly reduced caspase activities and TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling)-positive cells, suggesting reductions in apoptosis. IDN-6556 present in cold storage media ameliorated liver injury due to cold ischemia and reperfusion injury and may be a rational therapeutic approach to reduce the risk of liver ischemia in the clinical setting. Liver Transpl 13: 361,366, 2007. © 2007 AASLD. [source] Onset of Apoptosis in the Cystic Duct During Metamorphosis of a Japanese Lamprey, Lethenteron reissneriTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 7 2010Mayako Morii Abstract A nonparasitic lamprey in Japan, Lethenteron reissneri, stops feeding prior to the commencement of metamorphosis. Resumption of feeding cannot take place due to major alterations in the digestive system, including loss of the gall bladder (GB) and biliary tree in the liver. This degeneration of bile ducts is considered to depend on programmed cell death or apoptosis, but molecular evidence of apoptosis remains lacking. Using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining and immunohistochemistry with an antibody against active caspase-3, we showed that epithelial cells of the cystic duct (CD) and GB became TUNEL-positive by the early metamorphosing stage. Immunohistochemical staining of active caspase-3, a key mediator in the apoptotic cascade, showed that the apoptotic signal was initiated in the region around the CD in the late larval phase. In later stages, active caspase-3-positive epithelial cells were also observed in the large intrahepatic bile duct (IHBD) and peripheral small IHBDs. At the early metamorphosing stage, bile canaliculi between hepatocytes were dilated and displayed features resembling canaliculi in cholestasis. Onset of apoptosis around the CD, which is the pathway for the storage of bile juice, and progression of apoptosis towards the large IHBD, which is the pathway for the secretion of bile juice, may lead to temporary intrahepatic cholestasis. The present study represents the first precise spatial and temporal analysis of apoptosis in epithelial cells of the biliary tract system during metamorphosis of any lamprey species. Anat Rec 293:1155,1166, 2010. © 2010 Wiley-Liss, Inc. [source] | ||||||||||