Deoxynucleotidyl

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Deoxynucleotidyl

  • situ terminal deoxynucleotidyl
  • terminal deoxynucleotidyl

  • Terms modified by Deoxynucleotidyl

  • deoxynucleotidyl transferase
  • deoxynucleotidyl transferase dutp nick-end labeling

  • Selected Abstracts


    Differences and relationships of thymidine phosphorylase expression in tumor-associated macrophages and cancer cells in squamous cell carcinoma of the esophagus

    DISEASES OF THE ESOPHAGUS, Issue 1 2002
    N. Koide
    SUMMARY. Thymidine phosphorylase (TP), which has been shown to be identical to platelet-derived endothelial cell growth factor, is expressed in tumor-associated macrophages (TAMs) as well as cancer cells. The aim of this study was to clarify the differences or relationships of TP expression in TAMs and cancer cells in esophageal squamous cell carcinoma (SCC). Tissues samples were taken from 56 patients with esophageal SCC after curative surgery. The expression of TP in TAMs or SCC cells was examined using a monoclonal antibody to TP (clone 654,1). Microvessels in SCC that stained positively for Factor VIII-related antigen were counted (microvessel density, MVD). Macrophages in SCC that stained positively for CD68 antigen were counted (monocytic count). Ki-67 antigen was immunostained with MIB-1, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end labeling was performed, and Ki-67 labeling index (LI) and apoptotic index were calculated. The expression of TP in stromal cells and cancer cells was observed in 43 (76.8%) and 33 patients (58.9%), respectively. There were significant correlations between TP expression in stromal cells (TAMs) as well as in cancer cells and venous invasion, distant metastasis, or MVD. There was a correlation between TP expression in cancer cells and lymph node metastasis, and there were correlations between TP expression in TAMs and monocytic count or Ki-67 LI; however, there was no correlation between TP expression in TAMs and lymph node metastasis. On the other hand, in SCCs with TP expression in both TAMs and cancer cells, higher frequencies of venous invasion and distant metastasis, higher MVD and lower apoptotic index were observed than in other SCCs. The 5-year survival rate in patients with TP expression in both TAMs and cancer cells was poorer than that in patients with TP expression in neither TAMs and cancer cell. In conclusion, these results suggest that co-expression of TP in TAMs and cancer cells is strongly associated with angiogenic promotion and distant metastasis. However, other effects of TP, such as promotion of tumor growth and lymph node metastasis, may be different depending on whether these are expressed in TAMs or cancer cells in esophageal SCCs. Patients with coexpression of TP in TAMs and cancer cells may be associated with a poor prognosis. [source]


    Topical treatment with thiazolidinediones, activators of peroxisome proliferator-activated receptor-,, normalizes epidermal homeostasis in a murine hyperproliferative disease model

    EXPERIMENTAL DERMATOLOGY, Issue 3 2006
    Marianne Demerjian
    Abstract:, In a murine model of epidermal hyperplasia reproducing some of the abnormalities of several common skin disorders, we previously demonstrated the antiproliferative and pro-differentiating effects of peroxisome proliferator-activated receptor (PPAR),, PPAR,/,, and liver X receptor activators. Unlike other subgroups of PPAR activators, thiazolidinediones (TZDs), a family of PPAR, ligands, did not inhibit keratinocyte proliferation in normal murine skin. Here, we studied the effects of two TZDs, namely ciglitazone (10 mM) and troglitazone (1 mM), in the same murine model where epidermal hyperproliferation was reproduced by repeated barrier abrogation with tape stripping. Topical treatment with ciglitazone and troglitazone resulted in a marked and significant decrease in epidermal thickness. Furthermore, in all TZD-treated groups, we observed a significant decrease in keratinocyte proliferation using proliferating cell nuclear antigen, 5-bromo-2,-deoxyuridine, and tritiated thymidine incorporation. However, using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay, we found no difference in apoptosis between different treatments, emphasizing that it is the antiproliferative role of these activators that accounts for the decrease of epidermal thickness. Finally, using immunohistochemical methods, we determined the effects of ciglitazone on keratinocyte differentiation in this hyperproliferative model. We observed an increased expression of involucrin and filaggrin following ciglitazone treatment, suggesting a pro-differentiating action of TZDs in this model. In summary, topical TZDs significantly reduce epidermal keratinocyte proliferation while promoting differentiation in a murine model of hyperproliferative epidermis. Together, these results suggest that in addition to their metabolic effects currently in use in the treatment of type 2 diabetes, topical TZDs could be considered as potential alternative therapeutic agents in hyperproliferative skin diseases such as psoriasis. [source]


    Defining the caspase-containing apoptotic machinery contributing to cornification in human epidermal equivalents

    EXPERIMENTAL DERMATOLOGY, Issue 1 2006
    Vijaya Chaturvedi
    Abstract:, Whether terminal differentiation/stratum corneum formation of keratinocytes (KCs) represents a form of programmed cell death, utilizing mediators of classical apoptosis, is unclear. Apoptosis, an evolutionarily conserved death process, is comprised of extrinsic and intrinsic pathways, which converge using caspase 3. To define upstream and downstream caspases involved in terminal differentiation, we utilized human epidermal equivalents (EEs). Using submerged cultures comprised of human KCs, EEs were sequentially analyzed before and after being raised to an air/liquid (A/L) interface at 3,24 h intervals. At each time point, EEs were analyzed morphologically and for specific enzyme activity to distinguish different initiator (caspases 1, 2, 8, 9) and effector caspases (3, 6, 7). Terminal differentiation began at 6,8 h, as defined by stratum corneum with loricirin expression and completed at 18,24 h producing an epidermis resembling normal skin. Enzyme activity for caspases 1, 2, 3, 6, 7, 8, and 9 (but not 4, 5) was enhanced (>two-fold nmol/mg/h) at 3,6 h compared with submerged cultures. Processing of caspase 14 occurred at 18 h, and cleaved caspase 14 was increased at 24 h. Activated caspase 3-positive and terminal deoxynucleotidyl transferase-mediated nick end labeling-positive KCs were identified in EEs at 3,6 h corresponding to initiation sites of terminal differentiation. Addition of caspase inhibitors reduced levels of involucrin and loricrin in EEs raised to an A/L interface. We conclude caspases function as important death effectors strategically positioned at intersection of intrinsic and extrinsic pathways in KCs undergoing stratum corneum formation. [source]


    Pituitary adenylate cyclase-activating polypeptide attenuates streptozotocin-induced apoptotic death of RIN-m5F cells through regulation of Bcl-2 family protein mRNA expression

    FEBS JOURNAL, Issue 22 2008
    Satomi Onoue
    Oxidative stress, followed by the apoptotic death of pancreatic , cells, is considered to be one of causative agents in the evolution of the type 2 diabetic state; therefore, the protection of , cells can comprise an efficacious strategy for preventing type 2 diabetes. In the present study, RIN-m5F cells (i.e. the rat insulinoma , cell line) were stimulated with streptozotocin, resulting in a time- and concentration-dependent release of lactate dehydrogenase. There appeared to be significant apoptotic cell death after 2 h of treatment with streptozotocin at 10 mm, as demonstrated by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling staining and 2.6-fold activation of cellular caspase-3, an apoptotic enzyme. By contrast, some neuropeptides of the glucagon-secretin family and coenzyme Q10, an endogenous mitochondrial antioxidant, could attenuate streptozotocin cytotoxicity, and especially pituitary adenylate cyclase-activating polypeptide (PACAP), at a concentration of 10,7 m, exhibited 34% attenuation of lactate dehydrogenase release from streptozotocin-treated RIN-m5F cells. Quantitative RT-PCR experiments indicated the inhibitory effect of PACAP on streptozotocin-evoked up-regulation of pro-apoptotic factor (Noxa and Bax) and a 2.3-fold enhancement of Bcl-2 mRNA expression, a pro-survival protein, was also observed after addition of PACAP. The data obtained suggest the anti-apoptotic role of PACAP in streptozotocin-treated RIN-m5F cells through the regulation of pro-apoptotic and pro-survival factors. [source]


    Enhanced Expression of Transcription Factor E2F in Helicobacter pylori -infected Gastric Mucosa

    HELICOBACTER, Issue 3 2002
    Hajime Isomoto
    Abstract Objective.Helicobacter pylori is implicated in gastric carcinogenesis through increased gastric epithelial cell turnover. In fact, high proportions of proliferating and apoptotic epithelial cells are found in H. pylori -infected gastric mucosa. E2F, a transcription factor, induces coordinated transactivation of a set of genes involved in cell cycle progression. The aim of this study was to investigate the expression of E2F in H. pylori -infected gastric mucosa and examine the correlation between such expression and gastric epithelial cell proliferation and apoptosis. Methods. Twenty-five patients with H. pylori -associated gastritis (HAG) and 13 control subjects negative for H. pylori were examined. E2F expression was studied in situ by Southwestern histochemistry, a method used to localize transcription factors. Labeled double-stranded oligo-DNA with specific consensus sequence for E2F binding sites was reacted with frozen sections from antral biopsy specimens obtained at endoscopy. Gastric epithelial cell proliferation was assessed by immunostaining of proliferating cell nuclear antigen (PCNA), while apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL). The percentages of epithelial cells with nuclear staining for PCNA and E2F were expressed as a positivity index (PI). The percentage of TUNEL-positive epithelial cells was defined as apoptotic index. Results. E2F was expressed in the nuclei of gastric epithelial cells within gastric pits. E2F PI in H. pylori -infected gastric mucosa was significantly higher than that in noninfected. Expression of E2F correlated well with PCNA-positive epithelial cells. We also demonstrated colocalization of PCNA with E2F expression in the same epithelial cells. Apoptotic index was also high in H. pylori -infected mucosa, and correlated with E2F PI. Conclusion. Our results demonstrated a significant increase in the expression of E2F in H. pylori -infected mucosa, which correlated with both the percentages of PCNA- and TUNEL-positive cells. Our results suggest that enhanced E2F expression in gastric mucosa may be involved in H. pylori -related gastric carcinogenesis through accelerated cell turnover. [source]


    Interleukin 18 causes hepatic ischemia/reperfusion injury by suppressing anti-inflammatory cytokine expression in mice

    HEPATOLOGY, Issue 3 2004
    Dan Takeuchi
    Hepatic ischemia/reperfusion injury is a clinically important problem. While the mechanisms of the initial event and subsequent neutrophil-dependent injury are somewhat understood, little is known about the regulation of endogenous hepatoprotective effects on this injury. Interleukin 12 (IL-12) plays a role in the induction of this injury, but involvement of interleukin 18 (IL-18) has not been clarified. Using a murine model of partial hepatic ischemia and subsequent reperfusion, the aim of the current study was to determine whether IL-18 is up-regulated during hepatic ischemia/reperfusion and to determine the role of endogenous IL-18 in the development and regulation of inflammatory hepatic ischemia/reperfusion injury. Hepatic IL-18 expression was up-regulated from 1 to 8 hours after reperfusion. Hepatic ischemia/reperfusion induced nuclear factor-,B (NF-,B) and activator protein 1 (AP-1) activation, as defined by electrophoretic mobility shift assay, and caused significant increases in liver neutrophil recruitment, apoptosis, hepatocellular injury, and liver edema as defined by liver myeloperoxidase content, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end-labeling (TUNEL) staining, serum aminotransferase levels, and liver wet-to-dry weight ratios. In mice treated with neutralizing antibody to IL-18, ischemia/reperfusion-induced increases in CXC chemokine expression, activation of NF-,B and AP-1, and apoptosis were greatly reduced. Furthermore, under blockade of IL-18, anti-inflammatory cytokines such as IL-4 and IL-10 were greatly up-regulated. Signal transducer and activator of transcription 6 (STAT6) was significantly activated under blockade of IL-18. These conditions also caused significant reduction in liver neutrophil sequestration and liver injury. In conclusion, the data suggest that IL-18 is required for facilitating neutrophil-dependent hepatic ischemia/reperfusion injury through suppressing anti-inflammatory cytokine expression. (HEPATOLOGY 2004;39:699,710.) [source]


    Adult thymus transplantation with allogeneic intra-bone marrow,bone marrow transplantation from same donor induces high thymopoiesis, mild graft-versus-host reaction and strong graft-versus-tumour effects

    IMMUNOLOGY, Issue 4 2009
    Takashi Miyake
    Summary Although allogeneic bone marrow transplantation (BMT) plus donor lymphocyte infusion (DLI) is performed for solid tumours to enhance graft-versus-tumour (GVT) effects, a graft-versus-host reaction (GVHR) is also elicited. We carried out intra-bone marrow,bone marrow transplantation (IBM-BMT) plus adult thymus transplantation (ATT) from the same donor to supply alloreactive T cells continually. Normal mice treated with IBM-BMT + ATT survived for a long time with high donor-derived thymopoiesis and mild GVHR. The percentage of CD4+ FoxP3+ regulatory T cells in the spleen of the mice treated with IBM-BMT + ATT was lower than in normal B6 mice or mice treated with IBM-BMT alone, but higher than in mice treated with IBM-BMT + DLI; the mice treated with IBM-BMT + DLI showed severe GVHR. In tumour-bearing mice, tumour growth was more strongly inhibited by IBM-BMT + ATT than by IBM-BMT alone. Mice treated with IBM-BMT + a high dose of DLI also showed tumour regression comparable to that of mice treated with IBM-BMT + ATT but died early of GVHD. By contrast, mice treated with IBM-BMT + a low dose of DLI showed longer survival but less tumour regression than the mice treated with IBM-BMT + ATT. Histologically, significant numbers of CD8+ T cells were found to have infiltrated the tumour in the mice treated with IBM-BMT + ATT. The number of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labelling (TUNEL)-positive apoptotic tumour cells also significantly increased in the mice treated with IBM-BMT + ATT. Allogeneic IBM-BMT + ATT thus can induce high thymopoiesis, preserving strong GVT effects without severe GVHR. [source]


    Evidence for a perforin-mediated mechanism controlling cardiac inflammation in Trypanosoma cruzi infection

    INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 2 2002
    ANDREA HENRIQUES-PONS
    Summary. ,CD8+ T lymphocytes are considered an important cell population involved in the control of parasitaemia and mortality after Trypanosoma cruzi infection. However, despite recent developments in this field, the mechanism whereby this control is exerted is still not completely understood. Here we have used perforin knockout (,/,) mice infected with Y strain T. cruzi in order to evaluate specifically the participation of the perforin-based cytotoxic pathway in the destruction of cardiomyocytes, cellular inflammatory infiltration, and control of parasitaemia and mortality. We observed that although parasitaemia was equivalent in perforin (+/+) and (,/,) groups, survival rate and spontaneous physical performance were significantly lower in the perforin deficient mice. The cardiac inflammatory cell infiltration, mostly composed of CD8+ cells, was more evident in perforin (,/,) mice. Ultrastructural and immunofluorescence analysis, as well as plasma creatine kinase activity, revealed cardiomyocyte damage and necrosis, more evident in perforin (,/,) mice. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) assays performed in heart samples revealed similar and modest levels of apoptosis in both perforin (+/+) and (,/,) mice. These results indicate that perforin does not play a pivotal role in the control of parasitaemia and direct lysis of cardiomyocytes, but seems to be an important molecule involved in the control of cardiac inflammation and pathology induced by a highly virulent strain of T. cruzi. [source]


    Sevoflurane-induced post-conditioning has no beneficial effects on neuroprotection after incomplete cerebral ischemia in rats

    ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2010
    H.-M. LEE
    Background: The aim of this study was to investigate whether sevoflurane-induced post-conditioning has a neuroprotective effect against incomplete cerebral ischemia in rats. Methods: After cerebral ischemia by right common carotid artery occlusion in combination with hemorrhagic hypotension (35 mmHg) for 30 min, 1.0 minimum alveolar concentration of sevoflurane was administered for 15 min (Post-C 15, n=8), 30 min (Post-C 30, n=8), or 60 min (Post-C 60, n=8) in rats. Sevoflurane was not administered in control (n=8) and sham control rats (n=8). Neurologic evaluations were performed at 24, 48, and 72 h after ischemia. Degrees of neuronal damage in ischemic hippocampal CA1 and the cortex were assessed by counting eosinophilic neurons, and detection of DNA fragmentation was performed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining. Results: Neurologic deficit scores in the Post-C 60 group were higher than in the control group at 48 and 72 h post-ischemia (P<0.05). No differences were observed in the percentages of eosinophilic neurons among the control (CA1: 37.3 ± 25.4, cortex: 26.0 ± 8.9), Post-C 15 (CA1: 54.0 ± 21.4, cortex: 30.8 ± 19.9), or Post-C 30 (CA1: 68.4 ± 17.5, cortex: 38.0 ± 11.0) groups in ischemic CA1 and cortices. However, in the Post-C 60 group, the percentages of eosinophilic neurons were higher than in the control group in CA1 and cortices (P<0.05). The percentages of TUNEL-positive cell were similar in the control group and the post-conditioned groups. Conclusion: These findings show that sevoflurane administration after ischemia does not provide neuroprotection in rats subjected to incomplete cerebral ischemia. [source]


    Anatomic distribution of apoptosis in medulla oblongata of infants and adults

    JOURNAL OF ANATOMY, Issue 2 2008
    A. Porzionato
    Abstract The aim of the study was to evaluate the distribution of apoptosis in the medullary nuclei of infants and adults who died of hypoxic-ischaemic injury. Apoptosis was studied by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) in brainstems from 22 adults (7 subjects who died of opiate intoxication, 15 who died of other hypoxic-ischaemic injury) and 10 infants. The nuclei examined included the hypoglossal, dorsal motor nucleus of the vagus, nucleus tractus solitarii, nucleus of the spinal trigeminal tract, cuneate, vestibular and inferior olivary nuclei. A morphometric analysis with the optical disector method was performed to calculate the mean percentages (± standard deviation) of TUNEL-positive neuronal and glial cells for the sample populations. Opiate deaths did not have higher apoptotic indices than other adult hypoxic-ischaemic deaths. Statistically significant differences between adults and infants were found in the neuronal apoptotic indices of the cuneate (28.2 ± 16.3% vs. 6.9 ± 8.7%), vestibular (24.7 ± 15.0% vs. 11.3 ± 11.4%), nucleus tractus solitarii (11.2 ± 11.2% vs. 2.3 ± 2.4%), dorsal motor nucleus of the vagus (6.8 ± 8.5% vs. 0.1 ± 0.2%) and hypoglossal (6.6 ± 5.7% vs. 0.1 ± 0.2%), indicating higher resistance of the neuronal populations of these infant medullary nuclei to terminal hypoxic-ischaemic injury or post-mortem changes. Differences in neuronal apoptotic index were also statistically significant among nuclei, suggesting differential characteristics of survival. Nuclei with higher neuronal apoptotic indices were the cuneate, vestibular and nucleus of the spinal trigeminal tract, which are located in the lateral medullary tegmentum and share the same vascular supply from the posterior inferior cerebellar artery. [source]


    Comparison of the effects of erdosteine and N-acetylcysteine on apoptosis regulation in endotoxin-induced acute lung injury

    JOURNAL OF APPLIED TOXICOLOGY, Issue 4 2006
    Rezan Demiralay
    Abstract This study was carried out to investigate comparatively the frequency of apoptosis in lung epithelial cells after intratracheal instillation of endotoxin [lipopolysaccharide (LPS)] in rats and the role of tumor necrosis factor alpha (TNF- ,) on apoptosis, and the effects of erdosteine and N-acetylcysteine on the regulation of apoptosis. Female Wistar rats were given oral erdosteine (10,500 mg kg,1) or N-acetylcysteine (10,500 mg kg,1) once a day for 3 consecutive days. Then the rats were intratracheally instilled with LPS (5 mg kg,1) to induce acute lung injury. The rats were killed at 24 h after LPS administration. Lung tissue samples were stained with hematoxylin-eosin for histopathological assessments. The apoptosis level in the lung bronchial and bronchiolar epithelium was determined using the TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick endlabelling) method. Cytoplasmic TNF- , was evaluated by immunohistochemistry. Pretreatment with erdosteine and pretreatment with N-acetylcysteine at a dose of 10 mg kg,1 had no protective effect on LPS-induced lung injury. When the doses of drugs increased, the severity of the lung damage caused by LPS decreased. It was found that as the pretreatment dose of erdosteine was increased, the rate of apoptosis induced by LPS in lung epithelial cells decreased and this decrease was statistically significant in doses of 300 mg kg,1 and 500 mg kg,1. Pretreatment with N-acetylcysteine up to a dose of 500 mg kg,1 did not show any significant effect on apoptosis regulation. It was noticed that both antioxidants had no significant effect on the local production level of TNF- ,. These findings suggest that erdosteine could be a possible therapeutic agent for acute lethal lung injury and its mortality. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    Bis(4,7-dimethyl and 5-dinitro-1,10-phenanthroline) sulfato-oxovanadium(IV)-mediated in vivo male germ cell apoptosis

    JOURNAL OF APPLIED TOXICOLOGY, Issue 4 2001
    Osmond J. D'Cruz
    Abstract Oxovanadium(IV) [VO] complexes of 1,10-phenanthroline are a new class of potent apoptosis-inducing cytotoxic agents against human testicular cancer cells in vitro. The present study investigated the in vivo ability of four(bis)-chelated 1,10-phenanthroline [phen] complexes of sulfato-oxovanadium(IV),VO(phen)2, VO(Cl,phen)2, VO(Me2,phen)2 and VO(NO2,phen)2,with and without substitutions, to induce testicular germ cell apoptosis. Male germ cell loss in mice was measured by determining the epididymal sperm count, testicular weight and histological evaluation of the testes. Repetitive intratesticular injection (7.5 mg kg,1 testis,1) of bis-chelated 1,10-phenanthroline complexes of oxovanadium(IV) with 4,7-dimethyl [VO(Me2,phen)2] and 5-dinitro [VO(NO2,phen)2] substitution led to decreased sperm counts and reduced testicular weights. Histopathological examination of testicular sections from VO(Me2,phen)2 - and VO(NO2,phen)2 -treated mice revealed a marked inhibition of spermatogenesis and preferential loss of maturing, as well as elongated spermatids. In situ evaluation of seminiferous tubule cross-sections by terminal deoxynucleotidyl transferase-mediated FITC-deoxyuridine triphosphate nick end-labeling (TUNEL) and laser scanning confocal microscopy showed characteristic apoptotic germ cells delineating the periphery of the seminiferous tubules. The ability of bis-chelated 4,7-dimethyl- and 5-dinitro-substituted 1,10-phenanthroline complexes of oxovanadium(IV) to induce germ cell apoptosis in vivo may have potential utility in the treatment of human testicular germ cell tumors. Copyright © 2001 John Wiley & Sons, Ltd. [source]


    Apoptosis and Cardiopulmonary Bypass

    JOURNAL OF CARDIAC SURGERY, Issue 2 2007
    M.S., Miljenko Kova
    Apoptotic index (AI) obtained with in situ terminal deoxynucleotidyl transferase-labeled dUTP nick end labeling (TUNEL) method and Bak protein expression were compared. Patients and Methods: Twenty consecutive patients who underwent coronary artery bypass surgery, myocardial samples from the right atrium were taken in three stages: before cannulation (the first sample group), after declamping (the second sample group), and 20 minutes after reperfusion (the third sample group). The percentage of apoptotic cells was determined by TUNEL method. Expression of Bak protein was immunohistochemically analyzed. Intermittent ischemia and moderate hypothermia were used as methods of myocardial management during surgery. A statistical analysis was performed by using the Friedman ANOVA analysis of variances, the Kendall coefficient of concordance and the Wilcoxon matched pair test. Results: In the first sample group mean value of Bak expression was 2.61 ± 2.18, compared with AI 5.38 ± 3.58, after declamping (the second sample group) the mean value of Bak expression was 4.31 ± 2.68 while AI was 7.63 ± 4.38 and after 20 minutes of reperfusion in the third sample group mean value of Bak expression was 8.89 ± 4.45, while AI was 15.6 ± 8.45. When compared by using Wilcoxon matched pair test two methods significantly correlated, p > 0.0001. Conclusion: The positive correlation between AI obtained by TUNEL method and expression of Bak protein may suggest that apoptosis is activated mainly through mitochondrial activation pathway in ischemic reperfusion injury. The results suggest that ischemic reperfusion injury increases the AI in the right atrial tissue. If so, immunohistochemical expression of Bak protein could be used as a marker of myocardial ischemia induced injury. [source]


    Influence of cardiac-specific overexpression of insulin-like growth factor 1 on lifespan and aging-associated changes in cardiac intracellular Ca2+ homeostasis, protein damage and apoptotic protein expression

    AGING CELL, Issue 6 2007
    Qun Li
    Summary A fall in circulating levels of cardiac survival factor insulin-like growth factor 1 (IGF-1) contributes to cardiac aging. To better understand the role of IGF-1 in cardiac aging, we examined the influence of cardiac IGF-1 overexpression on lifespan, cardiomyocyte intracellular Ca2+ homeostasis, protein damage, apoptosis and expression of pro- and anti-apoptotic proteins in young and old mice. Mouse survival rate was constructed by the Kaplan,Meier curve. Intracellular Ca2+ was evaluated by fura-2 fluorescence. Protein damage was determined by protein carbonyl formation. Apoptosis was assessed by caspase-8 expression, caspase-3 and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling) assay. Pro- and anti-apoptotic proteins including Bax, p53, pp53, Bcl2, Omi/HtrA2, apoptosis repressor with caspase recruitment domain (ARC) and X-linked inhibitor of apoptosis protein (XIAP) were assessed by Western blot. Aging decreased plasma in IGF-1 levels, elevated myocyte resting intracellular Ca2+ levels, reduced electrically stimulated rise in intracellular Ca2+ and delayed intracellular Ca2+ decay associated with enhanced protein carbonyl formation, caspase-8 expression and caspase-3 activity in FVB mice, all of which with the exception of elevated resting intracellular Ca2+ were attenuated by IGF-1. Aging up-regulated expression of Bax, Bcl2 and ARC, down-regulated XIAP expression and did not affect p53, pp53 and Omi/HtrA2. The IGF-1 transgene attenuated or nullified aging-induced changes in Bax, Bcl2 and XIAP. Our data suggest a beneficial role for IGF-1 in aging-induced survival, cardiac intracellular Ca2+ homeostasis, protein damage and apoptosis possibly related to pro- and anti-apoptotic proteins. [source]


    Induction of Oxidative DNA Damage in the Peri-Infarct Region After Permanent Focal Cerebral Ischemia

    JOURNAL OF NEUROCHEMISTRY, Issue 4 2000
    Tetsuya Nagayama
    Abstract: To address the role of oxidative DNA damage in focal cerebral ischemia lacking reperfusion, we investigated DNA base and strand damage in a rat model of permanent middle cerebral artery occlusion (MCAO). Contents of 8-hydroxyl-2,-deoxyguanosine (8-OHdG) and apurinic/apyrimidinic abasic sites (AP sites), hallmarks of oxidative DNA damage, were quantitatively measured in nuclear DNA extracts from brains obtained 4-72 h after MCAO. DNA single- and double-strand breaks were detected on coronal brain sections using in situ DNA polymerase I-mediated biotin-dATP nick-translation (PANT) and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL), respectively. Levels of 8-OHdG and AP sites were markedly elevated 16-72 h following MCAO in the frontal cortex, representing the peri-infarct region, but levels did not significantly change within the ischemic core regions of the caudateputamen and parietal cortex. PANT- and TUNEL-positive cells began to be detectable 4-8 h following MCAO in the caudate-putamen and parietal cortex and reached maximal levels at 72 h. PANT- and TUNEL-positive cells were also detected 16-72 h after MCAO in the lateral frontal cortex within the infarct border, where many cells also showed colocalization of DNA single-strand breaks and DNA fragmentation. In contrast, levels of PANT-positive cells alone were transiently increased (16 h after MCAO) in the medial frontal cortex, an area distant from the infarct zone. These data suggest that within peri-infarct brain regions, oxidative injury to nuclear DNA in the form of base and strand damage may be a significant and contributory cause of secondary expansion of brain damage following permanent focal ischemia. [source]


    Pregnenolone Sulfate, a Naturally Occurring Excitotoxin Involved in Delayed Retinal Cell Death

    JOURNAL OF NEUROCHEMISTRY, Issue 6 2000
    C. Cascio
    Abstract: The present study was designed to investigate the neurosteroid pregnenolone sulfate (PS), known for its ability to modulate NMDA receptors and interfere with acute excitotoxicity, in delayed retinal cell death. Three hours after exposure of the isolated and intact retina to a 30-min PS pulse, DNA fragmentation as assessed by genomic DNA gel electrophoresis and a modified in situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method appeared concurrently with an increase in superoxide dismutase (SOD) activity and thiobarbituric acid-reactive substances (TBARS) levels. At 7 h, the increased amount of DNA laddering was accompanied by a higher number of TUNEL-positive cells in the inner nuclear and ganglion cell layers. Necrotic signs were characterized by DNA smear migration, lactate dehydrogenase (LDH) release, and damage mainly in the inner nuclear layer. PS-induced delayed cell death was markedly reduced by the NMDA receptor antagonists 4-(3-phosphonopropyl)-2-piperazinecarboxylic acid and 3,-hydroxy-5,-pregnan-20-one sulfate but completely blocked after concomitant addition of the non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione. Steroids with antioxidant properties (progesterone, dehydroepiandrosterone and its sulfate ester, and 17,-estradiol) differently prevented PS-induced delayed cell death. Cycloheximide treatment protected against DNA fragmentation and LDH release but failed to prevent the rise in SOD activity and TBARS level. We conclude that a brief PS pulse causes delayed cell death in a slowly evolving apoptotic fashion characterized by a cycloheximide-sensitive death program downstream of reactive oxygen species generation and lipid peroxidation, turning into secondary necrosis in a retinal cell subset. [source]


    Antiapoptotic and antiautophagic effects of glial cell line-derived neurotrophic factor and hepatocyte growth factor after transient middle cerebral artery occlusion in rats

    JOURNAL OF NEUROSCIENCE RESEARCH, Issue 10 2010
    Jingwei Shang
    Abstract Glial cell line-derived neurotrophic factor (GDNF) and hepatocyte growth factor (HGF) are strong neurotrophic factors, which function as antiapoptotic factors. However, the neuroprotective effect of GDNF and HGF in ameliorating ischemic brain injury via an antiautophagic effect has not been examined. Therefore, we investigated GDNF and HGF for changes of infarct size and antiapoptotic and antiautophagic effects after transient middle cerebral artery occlusion (tMCAO) in rats. For the estimation of ischemic brain injury, the infarct size was calculated at 24 hr after tMCAO by HE staining. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick end labeling (TUNEL) was performed for evaluating the antiapoptotic effect. Western blot analysis of microtubule-associated protein 1 light chain 3 (LC3) and immunofluorescence analysis of LC3 and phosphorylated mTOR/Ser2448 (p-mTOR) were performed for evaluating the antiautophagic effect. GDNF and HGF significantly reduced infarct size after cerebral ischemia. The amounts of LC3-I plus LC3-II (relative to ,-tubulin) were significantly increased after tMCAO, and GDNF and HGF significantly decreased them. GDNF and HGF significantly increased p-mTOR-positive cells. GDNF and HGF significantly decreased the numbers of TUNEL-, LC3-, and LC3/TUNEL double-positive cells. LC3/TUNEL double-positive cells accounted for about 34.3% of LC3 plus TUNEL-positive cells. This study suggests that the protective effects of GDNF and HGF were greatly associated with not only the antiapoptotic but also the antiautophagic effects; maybe two types of cell death can occur in the same cell at the same time, and GDNF and HGF are capable of ameliorating these two pathways. © 2010 Wiley-Liss, Inc. [source]


    Therapeutic benefits of intrathecal protein therapy in a mouse model of amyotrophic lateral sclerosis

    JOURNAL OF NEUROSCIENCE RESEARCH, Issue 13 2008
    Yasuyuki Ohta
    Abstract When fused with the protein transduction domain (PTD) derived from the human immunodeficiency virus TAT protein, proteins can cross the blood,brain barrier and cell membrane and transfer into several tissues, including the brain, making protein therapy feasible for various neurological disorders. We have constructed a powerful antiapoptotic modified Bcl-XL protein (originally constructed from Bcl-XL) fused with PTD derived from TAT (TAT-modified Bcl-XL), and, to examine its clinical effectiveness in a mouse model of familial amyotrophic lateral sclerosis (ALS), transgenic mice expressing human Cu/Zn superoxide dismutase (SOD1) bearing a G93A mutation were treated by intrathecal infusion of TAT-modified Bcl-XL. We demonstrate that intrathecally infused TAT-fused protein was effectively transferred into spinal cord neurons, including motor neurons, and that intrathecal infusion of TAT-modified Bcl-XL delayed disease onset, prolonged survival, and improved motor performance. Histological studies show an attenuation of motor neuron loss and a decrease in the number of cleaved caspase 9-, cleaved caspase 3-, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells in the lumbar cords of TAT-modified Bcl-XL -treated G93A mice. Our results indicate that intrathecal protein therapy using a TAT-fused protein is an effective clinical tool for the treatment of ALS. © 2008 Wiley-Liss, Inc. [source]


    Expressions of nitrotyrosine and TUNEL immunoreactivities in cultured rat spinal cord neurons after exposure to glutamate, nitric oxide, or peroxynitrite

    JOURNAL OF NEUROSCIENCE RESEARCH, Issue 5 2001
    Y. Manabe
    Abstract Although excitotoxic and oxidative stress play important roles in spinal neuron death, the exact mechanism is not fully understood. We examined cell damage of primary culture of 11-day-old rat spinal cord by addition of glutamate, nitric oxide (NO) or peroxynitrite (PN) with detection of nitrotyrosine (NT) or terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick end labeling (TUNEL). With addition of glutamate, NOC18 (a slow NO releaser) or PN, immunoreactivity for NT became stronger in the cytoplasm of large motor neurons in the ventral horn at 6 to 48 hr and positive in the axons of the ventral horn at 24 to 48 hr. TUNEL positive nuclei were found in spinal large motor neurons from 24 hr, and the positive cell number greatly increased at 48 hr in contrast to the vehicle. Pretreatment of cultures with ,-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)/kainate receptor antagonist, NO-suppressing agent, and antioxidant protected the immunoreactivity for NT or TUNEL. The present results suggest that both excitotoxic and oxidative stress play an important role in the upregulation of NT nitration and the apoptotic pathway in cultured rat spinal neurons. J. Neurosci. Res. 65:371,377, 2001. © 2001 Wiley-Liss, Inc. [source]


    Isoflurane attenuates dynorphin-induced cytotoxicity and downregulation of Bcl-2 expression in differentiated neuroblastoma SH-SY5Y cells

    ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2009
    G.-J. WU
    Background: It has been proposed that the volatile anesthetic isoflurane induces neuroprotection and that the endogenous opioid peptide dynorphin induces neurocytotoxicity in cells. The levels of dynorphin are often significantly elevated in neuropathophysiological conditions, and dynorphin can directly induce toxicity. However, the neuroprotective effects of isoflurane on dynorphin-induced cytotoxicity are still unclear. Methods: In order to determine the effect of isoflurane on dynorphin-induced cytotoxicity in neuronal cells, we have designed a device wherein cultured human neuroblastoma SH-SY5Y cells can be exposed to isoflurane. Fully differentiated SH-SY5Y cells were obtained by treating the cells with retinoic acid for 6 days. We examined SH-SY5Y cell survival, apoptosis, and antiapoptotic protein expression by cell viability, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling stain, and Western blot analysis, respectively. Results: After 16 h of dynorphin (10 ,M) treatment, the SH-SY5Y cells showed significant cytotoxicity, apoptosis, and downregulation of the antiapoptotic Bcl-2 protein expression. These effects of dynorphin were significantly inhibited by isoflurane exposure for 32 h [pretreatment for 16 h and posttreatment (after dynorphin treatment) for 16 h]. Conclusion: Thus, our results suggest that isoflurane exerts neuroprotective effects in the case of dynorphin-induced pathophysiological disruption. [source]


    Recently identified a novel neuropeptide manserin colocalize with the TUNEL-positive cells in the top villi of the rat duodenum

    JOURNAL OF PEPTIDE SCIENCE, Issue 6 2008
    Aika Yajima
    Abstract We recently isolated a novel 40 amino acid neuropeptide designated manserin from the rat brain. Manserin is derived from secretogranin II, a member of granin acidic secretory protein family by proteolytic processing, as previously reported secretoneurin and EM66. Manserin peptide are localized in the endocrine cells of the pituitary. In this study, we further investigated the manserin localization in the digestive system by immunohistochemical analysis using antimanserin antibody. In the duodenum, manserin immunostaining was exclusively observed in the nuclei of top villi instead of cytosol as observed in neurons in our previous study. Interestingly, manserin-positive cells in the duodenum are colocalized with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) positive cells, the cells whose DNA was damaged. Since the top villi of duodenum epithelial cells are known to undergo spontaneous apoptosis during epithelial cell turn over, and since other peptides such as secretoneurin and EM66 derived from SgII have been reported to be cancer-related, these results indicated that manserin peptide may have a role in apoptosis and/or cancer pathogenesis in the digestive organ. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd. [source]


    Pretreatment with the ciclosporin derivative NIM811 reduces delayed neuronal death in the hippocampus after transient forebrain ischaemia

    JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2010
    Masaaki Hokari Dr
    Abstract Objectives There have been several previous studies showing that ciclosporin, a ligand for cyclophilin D (CypD), reduces mitochondrial permeability transition (mPT) and ameliorates delayed neuronal death. NIM811 is a non-immunosuppressive ciclosporin derivative that also inhibits mPT, but has significantly less cytotoxicity than ciclosporin. Actually, in animal experiments, several investigators have reported that NIM811 ameliorates central nervous system disorders, such as traumatic brain injury, transient focal cerebral ischaemia and spinal cord injury. Therefore, we evaluated whether the ciclosporin derivative, NIM811 reduces mPT and ameliorates delayed neuronal death in the hippocampal CA1 sectors in mice when subjected to transient forebrain ischaemia. Methods Male C57BL/6 mice were treated with 50 mg/kg ciclosporin, 10, 50 or 100 mg/kg NIM811 or phosphate-buffered saline. At 30 min post-injection, all mice were subjected to 20 min bilateral common carotid artery occlusion (BCCAO). To estimate delayed neuronal death, the sections were prepared for HE staining and terminal deoxynucleotidyl transferase-mediated dUTP end-labelling (TUNEL) staining at 72 h after 20 min BCCAO. Furthermore, using 5,5,,6,6,-tetrachloro-1,1,,3,3,-tetraethylbenzimidazolocarbocyanine iodide (JC-1) staining technique, we evaluated whether NIM811 (1, 10, 100 or 1000 ,m) inhibited mPT in the neurons exposed to 100 ,m glutamate. Results Both delayed neuronal injury and apoptosis in the hippocampal CA1 sectors were significantly ameliorated at 72 h after transient forebrain ischaemia in the mice treated with 100 mg/kg NIM811 or 50 mg/kg ciclosporin. The treatments with 100 ,m and 1000 ,m NIM811 significantly inhibited the reduction of mitochondrial membrane potential in the neurons exposed to 100 ,m glutamate. Conclusions These findings strongly suggest that NIM811 inhibits mPT and ameliorates delayed neuronal death in mice subjected to transient forebrain ischaemia. [source]


    Rapid Induction of Apoptosis in Gastrulating Mouse Embryos by Ethanol and Its Prevention by HB-EGF

    ALCOHOLISM, Issue 1 2006
    Brian A. Kilburn
    Background: Ethanol exposure during gastrulation and early neurulation induces apoptosis within certain embryonic cell populations, leading to craniofacial and neurological defects. There is currently little information about the initial kinetics of ethanol-induced apoptosis, and interest in the ability of endogenous survival factors to moderate apoptosis is growing. Ethanol alters intracellular signaling, leading to cell death in chick embryos, suggesting that apoptosis could occur rapidly and that signaling pathways activated by survival factors might reduce apoptosis. Methods: Pregnant mice were intubated with 1, 2, or 4 g/kg ethanol on day 7.5 of embryogenesis (E7.5) 1, 3, or 6, hours before harvesting gastrulation-stage embryos. Control animals received maltose/dextran. Blood alcohol concentrations (BAC) were determined by gas chromatography. E7.5 embryos isolated from untreated dams were cultured in vitro for 1 or 3 hr with 0 or 400 mg% ethanol and 0 or 5 nM heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF). Apoptosis was quantified using fluorescence microscopy to detect annexin V binding and DNA fragmentation [terminal deoxynucleotidyl transferase-mediated dUTP-X nick end labeling (TUNEL)] in whole-mount or sectioned embryos. Results: Both annexin V binding and TUNEL were elevated (p<0.05) in embryos exposed in utero to 1 g/kg ethanol for 3 hours, increasing linearly with time and ethanol concentration. Apoptosis increased (p<0.05) in all germ cell layers. Mice treated with 4 g/kg sustained BAC of 400 mg% for nearly 3 hours, significantly increasing apoptosis within the first hour. Cultured embryos exposed to 400 mg% ethanol displayed 2- to 3-fold more TUNEL than vehicle-treated embryos (p<0.05); however, exogenous HB-EGF prevented apoptosis. Conclusions: Ethanol rapidly produced apoptosis in gastrulation-stage embryos, consistent with induction by intracellular signaling. The ethanol-induced apoptotic pathway was blocked by the endogenous survival factor, HB-EGF. Differences in the expression of survival factors within individual embryos could be partly responsible for variations in the teratogenic effects of ethanol among offspring exposed prenatally. [source]


    Ethanol Exposure Enhances Apoptosis Within the Testes

    ALCOHOLISM, Issue 10 2000
    Qianlong Zhu
    Background: Chronic ethanol abuse causes testicular atrophy and male infertility in alcoholic men. It is well known that ethanol exposure disrupts the hypothalamic-pituitary-gonadal axis, adversely affects the secretory function of Sertoli cells, and produces oxidative stress within the testes. It is still not clear what cellular mechanisms are responsible for the morphologic alteration of the testes that results in a reduction of testicular mass as a consequence of ethanol exposure. The hypothesis tested was that ethanol enhances apoptosis of testicular germ cells. Methods: In the experiments of chronic ethanol exposure, male Sprague Dawley® rats (Harlan Sprague Dawley, Inc., Indianapolis, IN) were fed Liber-Decarlie liquid diet for 9 weeks. In the experiments of acute ethanol exposure, a small volume of 20% ethanol solution was administered by intratesticular injection. Both 3,-end labeling of isolated testicular deoxyribonucleic acid (DNA) and labeling of apoptotic cells in situ by the terminal deoxynucleotidyl transferase-mediated deoxyuridine 5,-triphosphate nick end-labeling method were used to determine apoptosis rates within the testes. The expression of proteins involved in apoptosis was assessed by reverse transcription-polymerase chain reaction and by Western blotting. Results: The testes of rats that were fed an ethanol-containing liquid diet had more testicular DNA fragmentation than did those of animals that were fed an isocaloric control diet. Ethanol increased the number of apoptotic spermatogonia as well as spermatocytes. Direct intratesticular injections of ethanol solution enhanced testicular DNA fragmentation, suggesting an increase in apoptosis. Moreover, Fas ligand levels were increased within the testes of rats that were chronically fed ethanol. In vitro, ethanol treatment of cultured Sertoli cells enhanced the production of Fas ligand. In addition, testicular levels of p53 messenger ribonucleic acid were increased in rats that were chronically fed ethanol. Conclusions: All of these observations suggest that ethanol enhances testicular germ cell apoptosis. [source]


    Apoptotic cell death does not parallel other indicators of liver damage in chronic hepatitis C patients

    JOURNAL OF VIRAL HEPATITIS, Issue 3 2000
    Rodrigues
    The mechanisms of hepatocyte damage and the events that lead to high rates of chronic liver disease in hepatitis C virus (HCV) infection remain unclear. Recent in vitro studies have suggested that the HCV core protein may disrupt specific signalling pathways of apoptosis. This prompted us to study patients with chronic HCV infection to: determine the extent of apoptosis in the liver; evaluate whether clinical and biochemical data are correlated with histological findings; and to investigate if apoptosis is related to the histological activity of the disease. Twelve patients with chronic hepatitis C were included in the study. Liver histology was scored by using the histological activity index (HAI) of Knodell et al. DNA fragmentation was assessed in liver tissue by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labelling (TUNEL) assay. Routine methods were used to determine serum markers of liver disease. Bile acids were measured in serum and liver by gas chromatography. Patients were placed, according to their HAI score, into group A (3.8 ± 0.3) or group B (7.8 ± 0.8) (P < 0.01). Liver enzymes tended to be higher in group B patients than in patients of group A. Levels of toxic bile acids in serum were greater in patients than in controls (P < 0.01). Chenodeoxycholic acid values were slightly higher in serum and liver of patients in group A. Liver biopsies with low HAI scores showed an increased rate of apoptosis (18.0 ± 4.0 apoptotic cells per field) compared to those with higher HAI scores (6.6 ± 2.1, P < 0.05) or to controls (3.5 ± 0.4, P < 0.01). Hence, less severe liver disease, associated with lower histological grades and biochemistries, as well as increased levels of chenodeoxycholic acid, induces an expanded apoptotic response. The lower apoptotic rate in advanced liver disease may be associated with the high incidence of hepatocellular dysplasia/neoplasia. [source]


    Inverse Relationship Between Increased Apoptosis and Decreased Skin Cancer in UV-irradiated CD1d -/- Mice,

    PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 1 2005
    Yasuhiro Matsumura
    ABSTRACT We previously demonstrated that CD1d knockout mice were resistant to ultraviolet (UV)-induced immunosuppression. Because immune suppression is a critical factor in the development of UV-induced skin cancers, we investigated the response of wild type (WT) and CD1d -/- mice to UV carcinogenesis. We found that although 100% of WT mice developed skin tumors after 45 weeks of UV irradiation, only 60% of CD1d -/- mice developed skin tumors. To investigate the mechanisms involved in the resistance of CD1d -/- mice to UV-induced carcinogenesis, we determined the time course and kinetics of keratinocyte cell death after UV irradiation. After acute UV exposure, the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL)-positive keratinocytes were eliminated from the skin of WT mice by 72 h post-UV, but they still persisted until 96 h in CD1d -/- mice. The kinetics of p53 protein expression closely followed the kinetics of apoptotic cell death. Chronic UV irradiation resulted in induction of a significantly higher number of apoptotic keratinocytes in CD1d -/- than WT mice. In addition, epidermis and dermis from chronically UV-irradiated CD1d -/- mice harbored significantly fewer p53 mutations than WT mice. These results indicate that the resistance of CD1d -/- mice to UV carcinogenesis may be due to increased cell death and elimination of keratinocytes and fibroblasts containing DNA damage and p53 mutations. [source]


    Amygdala kindling develops without mossy fiber sprouting and hippocampal neuronal degeneration in rats

    PSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 6 2001
    Mariko Osawa MD
    Abstract Repeated electrical stimulation of limbic structures has been reported to produce the kindling effect together with morphological changes in the hippocampus such as mossy fiber sprouting and/or neuronal loss. However, to argue against a causal role of these neuropathological changes in the development of kindling-associated seizures, we examined mossy fiber sprouting in amygdala (AM)-kindled rats using Timm histochemical staining, and evaluated the hippocampal neuronal degeneration in AM-kindled rats by terminal deoxynucleotidyl transferase-mediated digoxigenin-11-dUTP nick end labelling (TUNEL). Amygdala kindling was established by 10.3 ± 0.7 electrical stimulations, and no increase in Timm granules (neuronal sprouting) was observed up to the time of acquisition of a fully kindled state. However, the density and distribution of Timm granules increased significantly in the dentate gyrus compared with unkindled rats after 29 after-discharges or more than 10 kindled convulsions. In addition, no significant increase in TUNEL-positive cells was found in the hilar polymorphic neurons or in CA3 pyramidal neurons of the kindled rats that had fewer than 29 after-discharges. However, a significant increase of TUNEL-positive cells was found in the granule cell layer in the dentate gyrus of the stimulated side after 18 after-discharges or 10 kindled convulsions. Our result show that AM kindling develops without evidence of mossy fiber sprouting, and that mossy fiber sprouting may appear after repeated kindled convulsions, following death of the granule cells in the dentate gyrus. [source]


    Expression of Apoptosis Regulatory Genes and Incidence of Apoptosis in Different Morphological Quality Groups of In Vitro-produced Bovine Pre-implantation Embryos

    REPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2010
    MG Melka
    Contents Apoptosis occurs during early development in both in vivo - and in vitro -produced embryos, and is considered as one of the causes of embryonic loss. The objectives of this study were, therefore, investigating stage-specific expression profiles of apoptosis regulatory genes in three quality groups of in vitro -produced bovine pre-implantation embryos; and analysing the relationship between cell number and DNA fragmentation with expressions of those genes. The relative abundance of mRNA of 9 pro- (Bax, caspase-9, Bcl-xs, P53, Caspase-3 and Fas) and anti- (Bcl-w and Mcl-1) apoptotic genes was analysed. Differential cell staining and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling were performed to analyse the variation in cell numbers and detect apoptotic nuclei respectively. Expression of Bax and Caspase-3 genes was significantly (p < 0.05) higher in poor quality pre-implantation embryos as compared with that of morphologically good quality embryos of the same developmental stages. Moreover, Mcl-1 expression was significantly higher in good quality immature oocytes than that in the poor quality group. Moreover, higher DNA fragmentation was evidenced in morphologically poor quality blastocysts. In conclusion, our study demonstrates that Bax, caspase-3 and Mcl-1 can be used as potential markers of embryo quality to evaluate in vitro -produced bovine embryos. Further studies are required to investigate specific molecular signatures that can be used in evaluating in vivo -derived embryos. [source]


    Involvement of the Klotho Protein in Dentin Formation and Mineralization

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 2 2008
    Hironobu Suzuki
    Abstract Klotho -deficient mice exhibit multiple pathological conditions resembling human aging. Our previous study showed alterations in the distribution of osteocytes and in the bone matrix synthesis in klotho -deficient mice. Although the bone and tooth share morphological features such as mineralization processes and components of the extracellular matrix, little information is available on how klotho deletion influences tooth formation. The present study aimed to elucidate the altered histology of incisors of klotho -deficient mice,comparing the findings with those from their wild-type littermates, by using immunohistochemistry for alkaline phosphatase (ALP), osteopontin, and dentin matrix protein-1 (DMP-1), terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphosphate nick end-labeling (TUNEL) detection for apoptosis, and electron probe microanalyzer (EPMA) analysis on calcium (Ca), phosphate (P), and magnesium (Mg). Klotho -deficient incisors exhibited disturbed layers of odontoblasts, predentin, and dentin, resulting in an obscure dentin-predentinal border at the labial region. Several odontoblast-like cells without ALP activity were embedded in the labial dentin matrix, and immunopositivity for DMP-1 and osteopontin was discernible in the matrix surrounding these embedded odontoblast-like cells. TUNEL detection demonstrated an apoptotic reaction in the embedded odontoblast-like cells and pulpal cells in the klotho -deficient mice. EPMA revealed lower concentrations of Ca, P, and Mg in the klotho -deficient dentin, except for the dentin around abnormal odontoblast-like cells. These findings suggest the involvement of the klotho gene in dentinogenesis and its mineralization. Anat Rec, 2007. © 2008 Wiley-Liss, Inc. [source]


    Expression of active caspase-3 in mitotic and postmitotic cells of the rat forebrain

    THE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2001
    Xiao-Xin Yan
    Abstract Active caspase-3 immunoreactivity was detected in the rat forebrain proliferative regions at birth and remained high in these areas for about 2 weeks, during which period labeled cells were present centroperipherally across the olfactory bulb. By the end of the third postnatal week, only a small number of immunolabeled cells remained in these forebrain structures. Active caspase-3 immunolabeling was localized mostly to cell nuclei and co-localized partially with TuJ1 and NeuN immunoreactivity, but not with glial fibrially acidic protein, OX-42, ,-aminobutyric acid, or terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL)-positive labeling. Active caspase-3 and 5-bromo-2,-deoxyuridine (BrdU) double-labeled nuclei were seen in the proliferative regions after 2 hours and in the periglomerular region of the bulb after 7 days following BrdU injections. Examination of the cells with electron microscopy confirmed that the active caspase-3-containing nuclei in the proliferative regions often had infoldings and appeared to be undergoing division. Some of the cells with active caspase-3-labeled nuclei in the bulb had synapses on their somata or dendrites. Labeled dendritic spines and a few axon terminals were also observed in the olfactory bulb. Taken together, it appears that a wave of active caspase-3-positive cells are dividing in the proliferative zones and then migrating to the bulb as they differentiate into neurons. Therefore, active caspase-3 may play a role in cellular processes such as neuronal differentiation, migration, and plasticity, in addition to its role in cell death. J. Comp. Neurol. 433:4,22, 2001. © 2001 Wiley-Liss, Inc. [source]