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Neonatal hypoxia-ischemia (HI) produces neurodegeneration and brain injury, and leads to behavioral and cognitive dysfunction. Hyperbaric oxygen (HBO) treatment may potentially be neuroprotective in HI injury. The aim of this study was to examine any neuroprotection by HBO treatment on long-term neurological function in the rat model of neontatal HI. Seven-day-old rats were subjected to HI or sham surgery. HBO treatment was administered (2.5 ATA for 90 min) 1h after hypoxia exposure. Sensorimotor (grip test and rota-rod) and cognitive tests (inhibitory avoidance and Morris water maze) were performed at postnatal day 28 to day 60. The extent of brain damage was determined by histological evaluation. Apoptosis, caspase-3 and apoptosis inducing factor (AIF) expression were assessed by immunohistochemistry 12, 24, and 48 h after HI. HI-treated animals had significantly worse sensorimotor and cognitive performances than those in the Sham group. HBO treatment led to significant improvements in neurobehavioral functions compared to the HI group, especially for cognitive performances. Morphological evaluation revealed a remarkable recovery of brain injury in the HBO group. Furthermore, the improvements in neurobehavioral impairments were correlated with the reduction in lesion size of the hippocampus and cerebral cortex. The proportion of apoptotic cells significantly increased with time after HI, and HBO significantly inhibited apoptotic cell death. The proportion of caspase-3 positive cells and nuclear AIF translocation increased and peaked at 24h after HI injury. HBO-treated rats showed decreased expression of these proteins compared to HI-treated animals. In conclusion, our results suggested that HBO treatment was effective in promoting long-term functional and histological recovery against neonatal HI brain injury. HBO-induced neuroprotection was associated with suppression of apoptosis by inhibiting caspase-3 and AIF-mediated pathways. Further studies evaluating its associated molecular and cellular mechanism are needed., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The purpose of this study was to determine the proper concentration of wortmannin that effectively inhibits PI3K/AKT but does not affect the proliferation and apoptosis of primary porcine preadipocytes. Firstly, primary porcine preadipocytes were isolated and their abilities to be induced to differentiation into mature adipocytes were evaluated. The preadipocytes were then treated with different concentrations of wortmannin, and the proliferation of the cells was detected with methanethiosulfonate (MTS). Annexin V- FITC/PI double-staining was used to detect the level of cell apoptosis. The apoptosis-related gene expressions were also quantified by qRT-PCR. At the same time, single cell electrophoresis was used to examine the extent of cellular DNA damage. Our data demonstrated that the primary porcine preadipocytes could differ-entiate into mature adipocytes. Up to 200 nmol/L of wortmannin had no effect on the proliferation ability of primary porcine preadipocytes (P>0.05). Results from the flow cytometry Annexin V- FITC/PI double-staining showed that 200 nmol/L wortmannin significantly induced apoptosis of the primary porcine preadipocytes (P<0.05). QRT-PCR results also showed that the expressions of caspase8, TNFR1, GZMB, and Bcl-x1 were significantly upregulated, while the expression of GZMA and cFLIP were not significantly affected when treated with 200 nmol/L wortmannin. In addition, results from the single cell gel electrophoresis indicated that 100 nmol/L wortmannin did not induce DNA damage. In conclusion, our results col-lectively showed that 100 nmol/L wortmanin can be used to study the role of PI3k pathway on the preadipocytes differen-tion without affecting the cell proliferation and apoptosis.

Aim: Through a third-butyl hydrogen peroxide (t-BHP) induced apoptosis in pancreatic islet β-cells to study the oxidative damage induced endoplasmic reticulum stress-JNK pathway of apoptosis related molecules in vitro., Methods: Mouse insulinoma(MIN6) cells was administered with t-BHP which were cultured in vitro. Choosing medicine with different concentrations(0-400 μmol/L)and time periods(0-8 h)to establish the cells apoptosis model. The percentage of cell viability was determined through CCK-8 assay. The percentage of apoptosis was determined through flow cytometric assay after Annexin-V-FITC-PI staining. The activity of caspase-3 was measured by the caspase-3 activity assay kit. The expression of Endoplasmic reticulum stress-related molecules and the apoptosis signal pathway IRE1, JNK, P-JNK, Caspase-3 were detected by Western blot., Results: The percentage of MIN6 cell viability was reducing with the concentration of t-BHP increasing. The Caspase-3 significantly change the activity after exposured of t-BHP in a concentration ≥ 25 μmol/L when the role of ≥1 h, With t-BHP concentration was increased, the role of prolonged, endoplasmic reticulum stress transmembrane protein IRE1α, P-JNK, active caspase-3 expression was significantly increased., Conclusion: The study demonstrates that the percentage of MIN6 cell viability was reduced in a dose-dependent manner. Continuous exposuring of t-BHP induced oxidative damage in MIN6 cells to endoplasmic reticulum stress and apoptosis. The expression of Endoplasmic reticulum stress and apoptosis pathway-related molecules in cell apoptosis in a dose and time-dependent.

Aims: To explore the effect and mechanism of exendin-4 on dexamethasone-induced apoptosis in pancreatic β-cells., Methods: Murine MIN6 pancreatic β-cells were treated with dexamethasone (100 nmol/l) over 48h following pretreatment with exendin-4 (100 nmol/l). Cell viability was determined using an MTT assay. The percentage of apoptotic cells was determined through fluorescence microscopy analysis after Hochest/PI staining and a flow cytometric assay after Annexin V-FITC/PI staining. Caspase 3 activity was measured using the caspase 3 activity assay kit. Expression of cyt-c, bcl-2, bax, AKT, and phosphorylated AKT was detected by western blot., Results: Exendin-4 reduced the percentage of cells undergoing apoptosis when β-cells were exposed to dexamethasone. Exendin-4 down-regulated caspase 3 activity, reduced cytochrome c levels in cytoplasm, and increased Bcl-2 protein levels and the Bcl-2 to Bax ratio in dexamethasone-treated β-cells. These exendin-4 effects were blocked in the presence of an inhibitor of the phosphoinositide-3 kinase (PI-3K) pathway or of the protein kinase A (PKA) pathway. Exendin-4 reversed dexamethasone-mediated inhibition of Akt phosphorylation, which was abrogated by the PI-3K and PKA inhibitors., Conclusion: PI-3K and PKA signaling are involved in the exendin-4-mediated modulation of β-cell apoptosis., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Thyroid cancer is the most common endocrine malignancy and exhibits the full range of malignant behaviors from the relatively indolent occult differentiated thyroid cancer to uniformly aggressive and lethal anaplastic thyroid cancer. Iodine is a well known key element in thyroid normal function maintenance and thyroid cancer development. However, the effects induced by iodine and the molecular mechanisms involved remain poorly understood in thyroid cancer. We investigated the apoptotic effect of iodine on three different subtypes of thyroid cancer cells. We observed that apoptosis induced by iodine was mitochondrial-mediated. Iodine treatment decreased the level of mutant p53 including the R273H mutant that possesses anti-apoptotic features, but increased the p21 level. Surprisingly, high doses of iodine promoted instead of suppressed the expression of anti-apoptotic protein Bcl-xL expression. Moreover, iodine transiently activated the subfamily members of mitogen activated protein kinases (MAPKs) (ERK1/2, p38 and JNK1/2) which contribute to modulate p53, p21 and Bcl-xL expression. The further results showed the three subfamily members of MAPKs all worked as anti-apoptotic factors. Collectively, iodine-induced apoptotic pathway is involved in the activation of MAPKs-related p21, Bcl-xL and mutant p53 regulation. The findings provide solid molecular evidence to explain the potential pathway for iodine to influence thyroid cancer development. It may also reveal some novel molecular targets for the treatment of thyroid cancer., ((c) 2010 Elsevier Ireland Ltd. All rights reserved.)

Aim: To investigate the chronic effect of palmitic acid (PA) on apoptosis of pancreatic islet beta-cells and the possible mechanism., Methods: Insulinoma cell line (MIN6 cells) were used in this study. After being incubated in PA (0.1 - 1.6 mml/L) for 24 and 48 hours, MTT method was used to evaluate the livability. After being incubated for 48 h, Hoechst-PI and Annexin-V-FTTC/PI FACS were used to estimate the apoptosis in each group, Western-blotting assay was used to estimate the protein level of p-Akt, Akt, Bax and Bcl-2., Results: Chronic PA dose-dependently (1) decreased the availability and increased the apoptosis of MIN6 cells; (2) decreased the phosphorylation of Akt and Bcl-2, but had no significant effects on Akt and Bax., Conclusion: Chronic PA dose-dependently induced apoptosis of MIN6 cells, and this effect was possibly regulated by Akt/Bcl-2.

This study is to investigate the effect of dexamethasone on cell apoptosis of murine MIN6 pancreatic beta-cells, and to investigate the mechanism of dexamethasone-dependent cell apoptosis. The cell apoptosis model was established by choosing the murine MIN6 pancreatic beta-cells, which was cultured in vitro and induced by dexamethasone. The morphology of the cell apoptosis was observed through fluorescence microscopic analysis after Hochest/PI staining and flow cytometric assay after Annexin-V/PI staining. The expression of caspase-3 was detected with caspase-3 activity assay kit. The expressions of Cyt-c, Bcl-2, Bax, AKT and p-AKT were observed with Western blotting. The results indicated that after exposure to dexamethasone at a concentration ranging from 50-800 nmol x L(-1) for 48 h, the percentage of cell apoptosis was significantly increased with the concentration over 100 nmol x L(-1) of dexamethasone; after exposure to dexamethasone (100 nmol x L(-1)) for 72 h, the activity of caspase-3 increased significantly; after exposure to dexamethasone at a concentration ranging from 50-800 nmol x L(-1) for 48 h, the expression of Cyt-c increased, Bcl-2 and AKT phosphorylation decreased while Bax and T-AKT remained unchanged. It could be concluded that the effect of dexamethasone on murine MIN6 pancreatic beta-cells apoptosis is significant. The mechanism of dexamethasone-dependent cell apoptosis is probably related to down regulation of the Bcl-2 expression and reduction of AKT phosphorylation.

Background: Breast cancer is one of the most common malignancies in women and is highly resistant to chemotherapy. Due to its high tumour selectivity, 3-bromopyruvic acid (3-BrPA), a well-known inhibitor of energy metabolism has been proposed as a specific anticancer agent. The present study determined the effect of 3-BrPA on proliferation, cell cycle and apoptosis in the human breast cancer MCF-7 cell line and other antitumour mechanisms., Methods: MCF-7 cells were treated with various concentrations of 3-BrPA for 1 - 4 days, and cell growth was measured by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay. Marked morphological changes in MCF-7 cells after treatment with 3-BrPA were observed using transmission electron microscopy. The distributions of the cell cycle and apoptosis were analyzed by flow cytometry. Immunohistochemistry was used to indicate the changes in the expression of Bcl-2, c-Myc, and mutant p53., Results: 3-BrPA (25 microg/ml) significantly inhibited the proliferation of MCF-7 cells in a time-dependent manner. The MCF-7 cells exposed to 3-BrPA showed the typical morphological characteristics of apoptosis, including karyopycnosis, nuclear condensation and oversize cytoplasmic particles. In addition, flow cytometric assay also showed more apoptotic cells after 3-BrPA stimulation. The cells at the G0 and G1 phases were dramatically decreased while cells at the S and G2/M phases were increased in response to 3-BrPA treatment after 48 hours. Furthermore, 3-BrPA stimulation decreased the expressions of Bcl-2, c-Myc and mutant p53, which were strongly associated with the programmed cell death signal transduction pathway., Conclusion: 3-BrPA inhibits proliferation, induces S phase and G2/M phase arrest, and promotes apoptosis in MCF-7 cells, which processes might be mediated by the downregulation of the expressions of Bcl-2, c-Myc and mutant p53.

IL-4-induced Stat6 signaling is active in a variety of cell types and plays a role in cell proliferation/growth and resistance to apoptosis. Using EMSA, we identified differential IL-4/Stat6 activities in colorectal cancer cell lines, HT-29 being active Stat6(high) phenotype and Caco-2 being defective Stat6(null) phenotype, respectively. Active Stat6(high) HT-29 cells exhibited resistance to apoptosis by flowcytometry and aggressive metastasis by Transwell assay compared with defective Stat6(null) Caco-2 cells. Comparing one another using RT-PCR, Stat6(high) HT-29 cells expressed more mRNA of anti-apoptotic and pro-metastatic genes Survivin, MDM2, and TMPRSS4, while Stat6(null) Caco-2 cells expressed more mRNA of pro-apoptotic and anti-metastatic genes BAX, CAV1, and P53, respectively. This is the first study describing correlations of IL-4/Stat6 activities with apoptosis and metastasis in colon cancer. These findings, together with the observation of constitutive Stat6 activation in many human malignancies, suggest that Stat6 activities could be a biomarker for cancer cell's invasive/metastatic capability.

IL-4-induced Stat6 signaling is active in a variety of cell types, including immune cells and cancer cells, and plays an important role in the regulation of gene expression. Using EMSA gel shift assay and an antibody to Stat6, we phenotyped two breast cancer cell lines, ZR-75-1 being active Stat6(high) phenotype and BT-20 being defective Stat6(null) phenotype, respectively. Breast cancer cells carrying Stat6(null) phenotype exhibited increased spontaneous apoptosis compared with those carrying Stat6(high) phenotype. Expression microarray analyses demonstrated that IL-4 upregulated CCL26, SOCS1, CISH, EGLN3, and SIDT1, and downregulated DUSP1, FOS, and FOSB, respectively, in these breast cancer cells. Among those genes, CCL26 and SOCS1 were known genes regulated by IL-4/Stat6 pathway, but CISH, EGLN3, SIDT1, DUSP1, FOS, and FOSB were novel genes demonstrated to be IL-4 responsive for the first time. IL-4 also upregulated 38 genes unique to Stat6(null) BT-20 cells and 23 genes unique to Stat6(high) ZR-75-1 cells, respectively. Furthermore, Stat6(high) and Stat6(null) cells showed very different profiles of constitutively expressed genes relevant to apoptosis and metastasis among others, which serve as a valuable expression database and warrant for detailed studies of IL-4/Stat6 pathway in breast cancer.

Recreational and occupational exposure to seawater (SW), have increased but the effect of SW on skin has not been elucidated. The purpose of present study was to assess the effects of SW immersion on the dorsal skin in hairless mice. Adult hairless mice were individually immersed in SW for 3 h, 6 h and 12 h; then, full-thickness dorsal skin of 2 cm diameter was excised for pathological examination (light microscope), apoptosis detection (terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling [TUNEL]) and proliferation index evaluation (immunohistochemistry). Normal and normal saline (NS)-immersed skin were used as controls. Histological examination revealed that there were randomly distributed cell deaths, presenting cell shrinkage, condensation of nuclear chromatin and eosinophilic cytoplasm in the epidermis, and neutrophil infiltration in the dermis, after SW immersion. Moreover, TUNEL showed low levels of apoptosis in normal (9.07 +/- 0.70%) and NS-immersed skin (9.99 +/- 1.22%). There was an apparent increase in the 6-h and 12-h SW immersed groups (29.90 +/- 6.85%, P < 0.01; 45.46 +/- 6.12%, P < 0.01, respectively). Ki-67 antigen was located in the basal layer of the epidermis and hair follicles, the rates of Ki-67-positive cells were 7.90 +/- 1.45% and 7.76 +/- 1.52% in normal and NS-immersed skin, respectively, and in the 12-h SW immersed group, the rate of Ki-67-positive cells reached 23.85 +/- 4.21% (threefold, P < 0.01). In each group, the rate of apoptosis was higher than that of proliferation. We conclude that SW immersion can cause time-dependent apoptosis and proliferation in the epidermis, and the overall effect of SW immersion is injury to the epidermis.

The study was aimed to explore the possible roles of survivin and P63 protein in the development and progression of B cell non-Hodgkin's lymphoma (B-NHL) and their relation with cell apoptosis and proliferation. TdT-mediated dUTP nick end labeling (TUNEL) and immunohistochemistry were used to detect the survivin and P63 protein expression, cell apoptosis and proliferating cell nuclear antigen (PCNA) level in 43 cases of B-NHL and 10 cases of reactive hyperplasia lymphoid (RHL) tissues. The results indicated that the positive rates of survivin and P63 protein expression were 69.8% (30/43) and 82.7% (30/43) respectively. The expression of survivin and P63 protein was 10% (1/10) and 40% (4/10) in RHL tissues of 10 cases. The expression of survivin in aggression B-NHL was higher than that in indolent B-NHL (83.3% vs 46.2%, P < 0.01). The expression of P63 proteins in aggressive B-NHL was higher than that in indolent B-NHL (86.7% vs 76.9%, P > 0.05). Apoptotic index (AI) and proliferation index (PI) correlated positively with expression of survivin (r = 0.429, P < 0.01; r = 0.348, P < 0.01), and so do with expression of P63 proteins (r = 0.451, P < 0.01; r = 0.369, P < 0.05). In addition, AI and PI were positively related (r = 0.598, P < 0.001). It is concluded that survivin may participate in the regulation mechanism of B-NHL cell apoptosis and proliferation, P63 as an oncogene enhances proliferation and takes part in the development of B-NHL. There may be a close relationship between survivin and P63 protein in the regulation of lymphocyte proliferative kinetics.

Objective: To explore the expression of myeloid cell leukemia 1 (MCL-1) proteins and survivin and its correlation with cell apoptosis as well as with the development and progression of B cell non-Hodgkin's lymphoma (B-NHL)., Methods: TdT-mediated dUTP nick end labeling and immunohistochemistry were used to study cell apoptosis and expression of MCL-1 proteins and survivin proteins in 43 patients with B-NHL and 10 with reactive hyperplasia (RH) lymphoid tissue., Results: The positive rate of MCL-1 proteins and survivin proteins was 58.1% (25/43) and 69.8% (30/43) respectively. The expression of MCL-1 proteins was not detected in RH lymphoid tissue, but that of survivin was detected in 10.0% (1/10). The expression of MCL-1 proteins in aggressive B-NHL was higher than that in indolent B-NHL (70.0 % vs 30.8 %, P < 0.05). The expression of survivin in aggressive B-NHL was also higher than that in indolent B-NHL (80.0% vs 46.2%, P < 0.05). Apoptotic index (AI) was not correlated positively with the expression of MCL-1, but correlated positively with the expression of survivin (r = 0.429, P < 0.01). MCL-1 and survivin were correlated positively in B-NHL (r = 0.598, P < 0.001)., Conclusions: MCL-1 proteins as family member of BCL-2 have no influence on apoptosis but survivin may participate in the regulation mechanism of B-NHL apoptosis. It is indicated that the two proteins with a close relationship may take part in the development and progression of B-NHL.

Iodine is a key element in the synthesis of thyroid hormones and the process of iodine transport by thyroid cells is active. Iodine deficiency, which is a known risk factor for thyroid cancer, may result from inadequate dietary iodine or from defects in iodine transportation. In contrast, a sufficient supply of iodine can induce cell-cycle arrest and apoptosis in thyroid cancer cells and may prevent the transformation of a differentiated thyroid cancer into a less differentiated or anaplastic form. However, the functions of iodine are complex, and the mechanisms of its action in thyroid cancer are unclear. This review focuses on the role of iodine in the carcinogenesis, proliferation, and apoptosis of thyroid cancers as well as on iodine transporters, most of which are impaired in thyroid cancer. Elucidating the roles of iodine may generate novel diagnostic and therapeutic approaches to thyroid cancer and improve current strategies for its treatment and prevention. [ABSTRACT FROM AUTHOR]