Association between Expression of 8-OHdG and Cigarette Smoking in Non-small Cell Lung Cancer

BACKGROUND: Exposure to cigarette smoking (CS) is a major risk factor for the development of lung cancer. CS is known to cause oxidative DNA damage and mutation of tumor-related genes, and these factors are involved in carcinogenesis. 8-Hydroxydeoxyguanosine (8-OHdG) is considered to be a reliable biomarker for oxidative DNA damage. Increased levels of 8-OHdG are associated with a number of pathological conditions, including cancer. There are no reports on the expression of 8-OHdG by immunohistochemistry in non-small cell lung cancer (NSCLC). METHODS: We investigated the expression of 8-OHdG and p53 in 203 NSCLC tissues using immunohistochemistry and correlated it with clinicopathological features including smoking. RESULTS: The expression of 8-OHdG was observed in 83.3% of NSCLC. It was significantly correlated with a low T category, negative lymph node status, never-smoker, and longer overall survival (p < .05) by univariate analysis. But multivariate analysis revealed that 8-OHdG was not an independent prognostic factor for overall survival in NSCLC patients. The aberrant expression of p53 significantly correlated with smoking, male, squamous cell carcinoma, and Ki-67 positivity (p < .05). CONCLUSIONS: The expression of 8-OHdG was associated with good prognostic factors. It was positively correlated with never-smokers in NSCLC, suggesting that oxidative damage of DNA cannot be explained by smoking alone and may depend on complex control mechanisms.

PI3Kδ contributes to ER stress-associated asthma through ER-redox disturbances: the involvement of the RIDD–RIG-I–NF-κB axis

Hyperactivation of phosphoinositol 3-kinase (PI3K) has been suggested to be a potential mechanism for endoplasmic reticulum (ER) stress-enhanced airway hyperresponsiveness, and PI3K inhibitors have been examined as asthma therapeutics. However, the regulatory mechanism linking PI3K to ER stress and related pathological signals in asthma have not been defined. To elucidate these pathogenic pathways, we investigated the influence of a selective PI3Kδ inhibitor, IC87114, on airway inflammation in an ovalbumin/lipopolysaccharide (OVA/LPS)-induced asthma model. In OVA/LPS-induced asthmatic mice, the activity of PI3K, downstream phosphorylation of AKT and activation of nuclear factor-κB (NF-κB) were all significantly elevated; these effects were reversed by IC87114. IC87114 treatment also reduced the OVA/LPS-induced ER stress response by enhancing the intra-ER oxidative folding status through suppression of protein disulfide isomerase activity, ER-associated reactive oxygen species (ROS) accumulation and NOX4 activity. Furthermore, inositol-requiring enzyme-1α (IRE1α)-dependent degradation (RIDD) of IRE1α was reduced by IC87114, resulting in a decreased release of proinflammatory cytokines from bronchial epithelial cells. These results suggest that PI3Kδ may induce severe airway inflammation and hyperresponsiveness by activating NF-κB signaling through ER-associated ROS and RIDD–RIG-I activation. The PI3Kδ inhibitor IC87114 is a potential therapeutic agent against neutrophil-dominant asthma.

Treatment of eggshell with casein phosphopeptide reduces the severity of ovariectomy-induced bone loss / 한국실험동물학회지

It has been generally accepted that calcium intake prevents bone loss, and frequent fracture resulted from osteoporosis. However, it is still elusive as to how effective sole calcium intake is in preventing or attenuating the severity of osteoporosis. Here, we demonstrate the effects of eggshell-casein phosphopeptide (ES-CPP), and compared these effects those of calcium supplement, for restoring ovariectomy-mediated bone loss. CPP, synthesized from the hydrolysis of casein (0.5%) using trypsin, was added to the grinded ES and was then administered to the ovariectomized (OVX) rat at 100 mg/kg for 4 weeks. Urine and feces from each group were collected each day, and were used to calculate the apparent calcium absorption rate in a day. After 4 weeks incubation, blood and femoral bones were isolated for the analysis of parameters representing osteoporosis. The apparent calcium absorption rate was significantly increased in the ES-CPP treated groups, in comparison to both the OVX and the commercial calcium supplement (CCS) treated group. Notably, treatment with ES-CPP markedly enhanced the calcium content in femoral bone and the relative weight of femoral bone to body weight, though calcium content in serum was barely changed by treatment with ES-CPP. Parameters of osteoporosis, such as osteocalcin in serum and bone mineral density, were rescued by treatment with ES-CPP, compared to treatment with commercial calcium supplement. This finding strongly suggests the possible use of ES-CPP in preventing or attenuating the severity of postmenopausal osteoporosis.

Gastrodia elata Blume and its pure compounds protect BV-2 microglial-derived cell lines against β-amyloid: The involvement of GRP78 and CHOP

Objectives: Gastrodia elata (GE) Blume (Orchidaceae) has been previously known for its therapeutic benefits against neurodegenerative diseases. Microglial activation and death have been implicated in the pathogenesis of a variety of neurodegenerative diseases, including Alzheimer's disease. In this study, GE and its pure components, gastrodin and 4-hydroxybenzyl alcohol (4HBA), were applied to β-amyloid-induced BV2 mouse microglial cells. Materials and Methods Cell viability was assessed by the MTT assay and Western blotting was also performed. Results: β-amyloid-induced cell death was shown to be induced time- and dose-dependently. To examine the cell death mechanism, we confirmed the involvement of ER stress signaling. C/EBP homologous protein (CHOP), a pro-apoptotic ER stress protein, was expressed at high levels but glucose-regulated protein 78 (GRP78), an anti-apoptotic ER stress protein with chaperone activity, was only slightly affected by treatment with β-amyloid. However, pretreatment with GE and its components inhibited the expression of CHOP but increased that of GRP78 in β-amyloid-treated cells. This study also showed that a single treatment with GE extracts, gastrodin, or 4HBA induced the expression of GRP78, a marker for enhanced protein folding machinery, suggesting a protective mechanism for GE against β-amyloid. Conclusions: This study reveals the protective effects of GE against β-amyloid-induced cell death, possibly through the enhancement of protein folding machinery of a representative protein, GRP78, and the regulation of CHOP in BV2 mouse microglial cells.

Effects of Chronic Mild Stress in Female Bax Inhibitor-1-Gene Knockout Mice

OBJECTIVE: The anti-apoptotic protein Bax inhibitor-1 (BI-1) is a regulator of apoptosis linked to endoplasmic reticulum (ER) stress, and BI-1-/- mice exhibit increased sensitivity to tissue damage. The purpose of this study was to investigate the role of BI-1 in the pathogenesis of chronic mild stress (CMS)-induced depression-like behaviors in BI-1-/- mice. METHODS: We delivered CMS for 2 or 6 weeks in BI-1-knockout and wild-type mice. Control groups of BI-1-knockout and wild-type mice were left undisturbed. The measured parameters were sucrose consumption at weeks 1, 2, 3, 4, 5, and 6, spontaneous locomotion, and a forced swimming test (FST) at weeks 2 and 6. RESULTS: Significant decreases in sucrose consumption and increases in immobility time in the FST were observed in both stress groups compared with the non-stress groups. Interestingly, at week 2, but not at week 6, BI-1-/--stress mice showed less sucrose intake and greater immobility time than did BI-1+/+-stress mice. CONCLUSION: These results suggest that BI-1 may play role in protecting against the depressogenic effects of CMS in the short term, but not in the long term. Further study is required to deepen understanding of the role of BI-1 in protecting against depression.

The Protective Effect of Epigallocatechin-3 Gallate on Ischemia/Reperfusion Injury in Isolated Rat Hearts: An ex vivo Approach

The aim of this study was to evaluate the preventive role of epigallocatechin-3 gallate (EGCG, a derivative of green tea) in ischemia/reperfusion (I/R) injury of isolated rat hearts. It has been suggested that EGCG has beneficial health effects, including prevention of cancer and heart disease, and it is also a potent antioxidant. Rat hearts were subjected to 20 min of normoxia, 20 min of zero-flow ischemia and then 50 min of reperfusion. EGCG was perfused 10 min before ischemia and during the whole reperfusion period. EGCG significantly increased left ventricular developed pressure (LVDP) and increased maximum positive and negative dP/dt (+/-dP/dtmax). EGCG also significantly increased the coronary flow (CF) at baseline before ischemia and at the onset of the reperfusion period. Moreover, EGCG decreased left ventricular end diastolic pressure (LVEDP). This study showed that lipid peroxydation was inhibited and Mn-SOD and catalase expressions were increased in the presence of EGCG. In addition, EGCG increased levels of Bcl-2, Mn-superoxide dismutase (SOD), and catalase expression and decreased levels of Bax and increased the ratio of Bcl-2/Bax in isolated rat hearts. Cleaved caspase-3 was decreased after EGCG treatment. EGCG markedly decreased the infarct size while attenuating the increase in lactate dehydrogenase (LDH) levels in the effluent. In summary, we suggest that EGCG has a protective effect on I/R-associated hemodynamic alteration and injury by acting as an antioxidant and anti-apoptotic agent in one.

4-phenylbutyric Acid Regulates Collagen Synthesis and Secretion Induced by High Concentrations of Glucose in Human Gingival Fibroblasts

High glucose leads to physio/pathological alterations in diabetes patients. We investigated collagen production in human gingival cells that were cultured in high concentrations of glucose. Collagen synthesis and secretion were increased when the cells were exposed to high concentrations of glucose. We examined endoplasmic reticulum (ER) stress response because glucose metabolism is related to ER functional status. An ER stress response including the expression of glucose regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), inositol requiring enzyme alpha (IRE-1alpha) and phosphoreukaryotic initiation factor alpha (p-eIF-2alpha) was activated in the presence of high glucose. Activating transcription factor 4 (ATF-4), a downstream protein of p-eIF-2alpha as well as a transcription factor for collagen, was also phosphorylated and translocalized into the nucleus. The chemical chaperone 4-PBA inhibited the ER stress response and ATF-4 phosphorylation as well as nuclear translocation. Our results suggest that high concentrations of glucose-induced collagen are linked to ER stress and the associated phosphorylation and nuclear translocation of ATF-4.

Apoptosis Induced by Manganese on Neuronal SK-N-MC Cell Line: Endoplasmic Reticulum (ER) Stress and Mitochondria Dysfunction

OBJECTIVES: Manganese chloride (MnCl2) is one of heavy metals for causing neurogenerative dysfunction like Manganism. The purpose of this study was to determine the acute toxicity of MnCl2 using different times and various concentrations including whether manganese toxicity may involve in two intrinsic pathways, endoplasmic reticulum (ER) stress and mitochondria dysfunction and lead to neuronal apoptosis mediated by organelle disorders in neuroblastoma cell line SK-N-MC. METHODS: In the acute toxicity test, five concentrations (200, 400, 600, 800, 1,000 uM) of MnCl2 with 3, 6, 12, 24, 48 hours exposure were selected to analyze cell viability. In addition, to better understand their toxicity, acute toxicity was examined with 1,000 uM MnCl2 for 24 hours exposure via reactive oxygen species (ROS), mitochondria membrane potential, western blotting and mitochondrial complex activities. RESULTS: Our results showed that both increments of dose and time prompt the increments in the number of dead cells. Cells treated by 1,000 microM MnCl2 activated 265% (+/-8.1) caspase-3 compared to control cell. MnCl2 induced intracellular ROS produced 168% (+/-2.3%) compared to that of the control cells and MnCl2 induced neurotoxicity significantly dissipated 48.9% of mitochondria membrane potential compared to the control cells. CONCLUSIONS: This study indicated that MnCl2 induced apoptosis via ER stress and mitochondria dysfunction. In addition, MnCl2 affected only complex I except complex II, III or IV activities.

PDTC Inhibits TNF-alpha-Induced Apoptosis in MC3T3E1 Cells

Osteoblasts are affected by TNF-alpha overproduction by immune cells during inflammation. It has been suggested that functional NF-kappaB sites are involved in TNF-alpha-induced bone resorption. Thus, we explored the effect of pyrrolidine dithiocarbamate (PDTC), which potently blocks the activation of nuclear factor (NF-kappaB), on the induction of TNF-alpha-induced activation of JNK/SAPK, AP-1, cytochrome c, caspase and apoptosis in MC3T3E1 osteoblasts. Pretreatment of the cells with PDTC blocked TNF-alpha-induced NF-kappaB activation. TNF-alpha-induced activation of AP-1, another nuclear transcription factor, was suppressed by PDTC. The activation of c-Jun N-terminal kinase, implicated in the regulation of AP-1, was also down regulated by PDTC. TNF-alpha-induced apoptosis, release of cytochrome c and subsequent activation of caspase-3 were abolished by PDTC. TNF-alpha-induced apoptosis was partially blocked by Ac-DEVD-CHO, a caspase-3 inhibitor, suggesting that caspase-3 is involved in TNF-alpha- mediated signaling through NF-kappaB in MC3T3E1 osteoblasts. Thus, these results demonstrate that PDTC, has an inhibitory effect on TNF-alpha-mediated activation of JNK/SAPK, AP-1, cytochrome c release and subsequent caspase-3, leading to the inhibition of apoptosis. Our study may contribute to the treatment of TNF-alpha-associated immune and inflammatory diseases such as rheumatoid arthritis and periodontal diseases.

Salicylate Regulates Cyclooxygenase-2 Expression through ERK and Subsequent NF-kappaB Activation in Osteoblasts

The expression of cyclooxygenase-2 (COX-2) is a characteristic response to inflammation and can be inhibited with sodium salicylate. TNF-alpha plus IFN-gamma can induce extracellular signal-regulated kinase (ERK), IKK, IkappaB degradation and NF-kappaB activation. The inhibition of the ERK pathway with selective inhibitor, PD098059, blocked cytokine-induced COX-2 expression and PGE2 release. Salicylate treatment inhibited COX-2 expression induced by TNF-alpha/IFN-gamma and regulated the activation of ERK, IKK and I kappaB degradation and subsequent NF-kappaB activation in MC3T3E1 osteoblasts. Furthermore, antioxidants such as catalase, N-acetyl-cysteine or reduced glutathione attenuated COX-2 expression in combined cytokines-treated cells, and also inhibited the activation of ERK, IKK and NF-kappaB in MC3T3E1 osteoblasts. In addition, TNF-alpha/IFN-gamma stimulated ROS release in the osteoblasts. However, salicylate had no obvious effect on ROS release in DCFDA assay. The results showed that salicylate inhibited the activation of ERK and IKK, IkappaB degradation and NF-kappaB activation independent of ROS release and suggested that salicylate exerts its anti-inflammatory action in part through inhibition of ERK, IKK, IkappaB, NF-kappaB and resultant COX-2 expression pathway.

Blockade of p38 Mitogen-activated Protein Kinase Pathway Inhibits Interleukin-6 Release and Expression in Primary Neonatal Cardiomyocytes

The induction of interleukin-6 (IL-6) using combined proinflammatory agents (LPS/IFN-gamma or TNF-alpha/IFN-gamma) was studied in relation to p38 mitogen-activated protein kinase (MAPK) and NF-kappaB transcriptional factor in primary neonatal cardiomyocytes. When added to cultures of cardiomyocytes, the combined agents (LPS/IFN-gamma or TNF-alpha/IFN-gamma) had stimulatory effect on the production of IL-6 and the elevation was significantly reduced by SB203580, a specific p38 MAPK inhibitor. SB203580 inhibited protein production and gene expression of IL-6 in a concentration-dependent manner. In this study, IFN-gamma enhancement of TNF-alpha-induced NF-kappaB binding affinity as well as p38 MAP kinase activation was observed. However, a specific inhibitor of p38 MAPK, SB203580, had no effect on TNF-alpha/IFN-gamma or LPS/IFN-gamma-induced NF-kappaB activation. This study strongly suggests that these pathways about TNF-alpha/IFN-gamma or LPS/IFN-gamma-activated IL-6 release can be primarily dissociated in primary neonatal cardiomyocytes.

Transition metal induces apoptosis in MC3T3E1 osteoblast: Evidence of free radical release

Transition metal ions including Se2+, Cd2+, Hg2+ or Mn2+ have been thought to disturb the bone metabolism directly. However, the mechanism for the bone lesion is unknown. In this study, we demonstrated that MC3T3E1 osteoblasts, exposed to various transition metal ions; selenium, cadmium, mercury or manganese, generated massive amounts of reactive oxygen species (ROS). The released ROS were completely quenched by free radical scavengers-N-acetyl cysteine (NAC), reduced glutathione (GSH), or superoxide dismutase (SOD). First, we have observed that selenium (10 micrometer), cadmium (100 micrometer), mercury (100 micrometer) or manganese (1 mM) treatment induced apoptotic phenomena like DNA fragmentation, chromatin condensation and caspase-3-like cysteine protease activation in MC3T3E1 osteoblasts. Concomitant treatment of antioxidant; N-acetyl-L-cysteine (NAC), reduced-form glutathione (GSH), or superoxide dismutase (SOD), prevented apoptosis induced by each of the transition metal ions. Catalase or dimethylsulfoxide (DMSO) has less potent inhibitory effect on the apoptosis, compared with NAC, GSH or SOD. In line with the results, nitroblue tetrazolium (NBT) stain shows that each of the transition metals is a potent source of free radicals in MC3T3E1 osteoblast. Our data show that oxidative damage is associated with the induction of apoptosis in MC3T3E1 osteoblasts following Se2+, Cd2+, Hg2+ or Mn2+ treatment.

Effect of cytokines and bFGF on the osteoclast differentiation induced by 1 alpha,25-(OH)2D3 in primary murine bone marrow cultures

Bone is a complex tissue in which resorption and formation continue throughout life. The bone tissue contains various types of cells, of which the bone forming osteoblasts and bone resorbing osteoclasts are mainly responsible for bone remodeling. Periodontal disease represents example of abnormal bone remodeling. Osteoclasts are multinucleated cells present only in bone. It is believed that osteoclast progenitors are hematopoietic origin, and they are recruited from hematopoietic tissues such as bone marrow and circulating blood to bone. Cells present in the osteoclast microenvironment include marrow stromal cells, osteoblasts, macrophages, T-lymphocytes, and marrow cells. These cells produce cytokines that can affect osteoclast formation. In vitro model systems using bone marrow cultures have demonstrated that IL-1 beta, IL-3, TNF-alpha, bFGF can stimulate the formation of osteoclasts. In contrast, IL-4 inhibits osteoclast formation. Knowledge of cytokines and bFGF that affect osteoclast formation and their capacity to modulate the bone-resorbing process should provide critical insights into normal calcium homeostasis and disorders of bone turnover such as periodontal disease, osteoporosis and Paget's disease.

Systemic injection of lidocaine induce expression of c-fos mRNA and protein in adult rat brain

Both direct and indirect environmental stress to brain were increase the expression of transcription factor c-fos in various populations of neurons. In this study, we examined whether the intraperitoneal injections of lidocaine at doses inducing convulsion within 10 min increased the level of c-fos mRNA and protein in forebrain areas. In situ hybridization using (35S)UTP-labeled antisense c-fos, cRNA increased c-fos mRNA levels though hippocampal formation, piriform cortex, septum, caudate-putamen, neostriatum, and amygdala within 2 hr. In parallel with the mRNA expression, c-FOS protein immunoreactivity was also observed in the same forebrain areas. In contrast to the seizure activity and widespread neuronal degeneration following a kainate treatment, injections of lidocaine did not produce neuronal death within 3 days. The present study indicates that lidocaine induces convulsion and c-fos expression without causing neuro-toxicity.

Physiological Role of PGE2 and DBcAMP in Bone Cell Metabolism / 대한면역학회지

One of the primary functions for which bones have evolved is to act as a structural support. To achieve this, bones remodel throughout life so that their structure remains optimal for the prevailing mechanical environment. Bone remodeling consists of an initial phase of osteoclastic bone resorption followed by a bone formation period. Prostaglandins are potent regulators of bone formation and bone resorption that can have both stimulatory and inhibitory effects. Elevation of intracellular cAMP is an important intracellular signaling mechanism involved in the regulation of the expression of many proteins. In this study we examine whether PGE or DBcAMP affects osteoblastic activation or osteoclastic differentiation in mouse bone marrow cells and osteosarcoma ROS 17/2.8 cells. The effect of PGE and DBcAMP on the cell proliferation was measured by the incorporation of [3H]- thymidine into DNA. As a result, PGE2 (0.5-1 ug/ml) and DBcAMP (0.1-0.5 mM) inhibited the [3H]-thymidine incorporation into DNA in a dose dependent manner. The effect of PGE2 and DBcAMP on the induction of alkaline phosphatase (ALP) was investigated in ROS 17/2.8 cells cultured in medium containing 0.4% fetal bovine serum. PGE and DBcAMP stimulated ALP activity in the cells in a dose- dependent manner. PGE2 also increased the intracellular cAMP content in a dose- dependent fashion with a maximal effect at 0.5 ug/ml. ROS 17/2.8 cells release nitric oxide upon stimulation of PGE2 or DBcAMP with interferon-r. PGE2 and DBcAMP increase the phosphorylation level of CREB (cAMP response element binding protein) without any change on the amount of CREB protein. Also, PGE (10-6 M) and DBcAMP (10-4 M) significantly increase the generation of osteoclasts in mouse bone marrow cell culture system. In conclusion, the results of this study suggested that cAMP appears to be an important regulatory molecule in the processes of bone formation and resorption.