8-OHdG Expression Research Articles

Analytics of oxidative stress markers in the early diagnosis of oxygen DNA damage.

Under homeostatic conditions, an equilibrium state between amounts of free radicals formed and their scavenging is observed. Free radicals are destructive only when present in excess. Pathological changes within cells and tissues can result from a persistent excess of free radicals. Living organisms are increasingly exposed to oxidative stress, resulting in oxidative DNA modifications. One such modification is 8-hydroxy-2'-deoxyguanosine (8-OHdG). It is considered a biomarker of oxidative stress and oxidative DNA damage. It has been found both in physiological fluids and in cells. This paper presents methods found in the literature for determining 8-OHdG expression in various kinds of biological material - blood, urine or liver homogenates. Methods for determining the biomarker expression have been grouped into direct and indirect methods, and the various levels of 8-hydroxy-2'-deoxyguanosine that can be determined by the different techniques are presented. The basic pros and cons of the various techniques are also discussed.

Abstract TP265: AATF Protects Neuron Against Ischemia via Regulating PAR/AIF Pathway

Abstract: Apoptosis antagonizing transcription factor (AATF) exerts an effect against oxidative stress, DNA damage and cellular apoptosis. However, its role in neuronal ischemia or hypoxia damage has not been elucidated yet. Present study investigated the neuroprotective roles and mechanisms of AATF under ischemia and hypoxia in vivo and in vitro. Focal cerebral ischemia of rat was generated by distal middle cerebral artery occlusion (dMCAO) model, SH-SY5Y cells were used to generate oxygen glucose deprivation (OGD) model in vitro. Western blot and immunofluorescent staining were used to investigate the expression changes of AATF. CCK-8 and LDH were performed to evaluate cellular survival and cytotoxicity. Overexpression and interference lentivirus vectors were performed to regulate the expression of AATF in SH-SY5Y cells. DHE staining that measured by flow cytometry was performed to investigate cellular superoxide anion levels. 8-OHdG expression and AP sites measurement were used to evaluate DNA damage. DNA Ladder and TUNEL staining were employed to evaluate DNA fragmentation. MNNG and DPQ were respectively used to agitate or antagonist caspase-3 independent PCD (programmed cell death) pathway, STS and Z-VAD-fmk were respectively used to agitate or antagonist caspase-3 dependent PCD pathway. Western blot was performed to investigate the expression of Poly(ADP-ribose) polymers (PAR) and apoptosis inducing factor (AIF) in different cellular components, Co-IP (co-immunoprecipitation) was used to test the interaction of AIF, H2AX and CypA (Cyclophilin A). We found that AATF was increased in cortical neurons after brain ischemia (P<0.001). Besides, AATF was upregulated in OGD-treated SH-SY5Y cells in a time-dependent manner (P=0.007). Additionally, overexpressing AATF ameliorated OGD-induced cellular death (P < 0.001) and cytotoxicity (P = 0.001), and AATF interference exacerbated OGD-induced cellular death (P=0.033) and cytotoxicity (P=0.006). We also found that AATF overexpression suppressed cellular DNA fragmentation (P=0.003) but did not ameliorate oxidative stress and DNA damage. Moreover, we discovered that overexpressing AATF suppressed PAR/AIF signaling pathway via binding with AIF.

Salvianolate protects H9c2 cells from hypoxia/reoxygenation injury-induced apoptosis by attenuating mitochondrial DNA oxidative damage

Objective: To investigate the possible mechanism related to the protective effects of salvianolate in H9c2 cells underwent hypoxia/reoxygenation (H/R)-injury. Methods: H9c2 cells were divided into four groups: control group, salvianolate group (S group), H/R group, and salvianolate+ H/R group(S+ H/R group), in which the H9c2 cells were pretreated with salvianolate before H/R-treatment.Apoptotic cells were detected by Tunel assays and AnnexinⅤ-FITC apoptosis detection kit.The intracellular ATP level, the change of mitochondrial membrane potential and the mitochondrial DNA oxidative damage were also determined in these groups. Results: (1) The apoptosis rate of H/R group(26.36±5.14)% was significantly higher compared to control group(2.71±1.66)%(P=0.000 4), which could be significantly reduced in S+ H/R group(17.28±4.75)%(P=0.012 8 vs. H/R group , P=0.003 9 vs. control group). The ratio of AnnexinⅤ and PI double positive cells in H/R group(28.23±6.73)% was significantly higher compared to control group(3.53±2.83)%(P=0.001 1), which was significantly reduced in S+ H/R group(18.10±4.56)%(P=0.037 2 vs. H/R group, P=0.038 3 vs. control group). (2)The ATP level of H9c2 cells in H/R group(49.05±10.12)% was significantly lower than in control group 100%(P=0.000 5), which was significantly increased in S+ H/R group(68.67±13.32)%(P=0.019 9 vs. H/R group). Confocal microscope showed that red fluorescence was dominant in the control group, red fluorescence was significantly reduced, while green fluorescence was significantly increased in H9c2 cells of H/R group and the fluorescence ratio of red to green in H/R group((37.13±8.47)%) was significantly decreased compared to control group (100%, P=0.000 1), fluorescence ratio of red to green was significantly increased in S+ H/R group((63.77±12.32)% vs. H/R group, P=0.007 3). (3)The mitochondrial DNA oxidative damage in different groups: there was only few 8-hydroxyguanine (8-OHdG) expression, which marked as green, in control group, and 8-OHdG expression was significantly upregulated in H/R group, moreover, the 8-OHdG was co-localized with mitochondria.The expression of 8-OHdG was significantly lower in S+ H/R group compared to H/R group. Conclusion: Salvianolate can reduce mitochondrial DNA oxidative damage, and protect mitochondrial function, thus inhibit myocardial cell apoptosis and eventually reduce the myocardial H/R-injury in H9c2 cells.

The significance of 8-hydroxy-deoxyguanosine acid in the diagnosis of nonalcoholic steatohepatitis

Objective: To evaluate the significance of serum 8-hydroxy-deoxyguanosine acid(8-OHdG) in the diagnosis of nonalcoholic steatohepatitis (NASH). Methods: Patients or healthy subjects were enrolled at the Second Hospital of Tianjin Medical University and the Second People's Hospital of Tianjin from May 2013 to December 2015. A total of 41 patients with nonalcoholic fatty liver disease were enrolled in the study, including 20 nonalcoholic simple fatty liver (NAFL) patients and 21 NASH patients whose diagnosis were proven by liver biopsy. The other 32 healthy subjects were studied as controls. Serum 8-OHdG, ALT, AST and GGT were tested. Nonalcoholic fatty liver disease activity score (NAS) and expression of 8-OHdG in liver was investigated between NAFL patients and NASH patients. The correlations between serum 8-OHdG and serum ALT, AST, GGT, and 8-OHdG in liver tissue in NASH group were investigated. In addition, the receiver operating characteristic (ROC) curve analyses for ALT and 8-OHdG levels were performed in NAFL patients and NASH patients, and the cut-off value was determined. Results: Serum 8-OHdG values in healthy controls, NAFL and NASH patients were (0.19±0.16) μg/L, (0.22±0.16) μg/L, (0.42±0.21) μg/L respectively. The serum 8-OHdG and serum ALT, GGT and 8-OHdG in liver tissue were all positively correlated in NASH group with respective correlation coefficient r values as 0.454 7, 0.382 9, and 0.497 6. AUC of 8-OHdG was 0.901 with cut-off value 0.39 μg/L. Its sensitivity was 88.3% and specificity was 81.5%, which were higher than those of ALT. Conclusion: The value of serum 8-OHdG would be used as a marker for the diagnosis of NASH.

Taurine Administration Mitigates Cisplatin Induced Acute Nephrotoxicity by Decreasing DNA Damage and Inflammation: An Immunocytochemical Study.

Cisplatin (CDDP) is one of the most effective chemotherapeutic agent used in the treatment of many kind of solid tumors. Its primary side effect is nephrotoxicity. The aim of this study to investigate the effects of taurine on cisplatin-induced acute nephrotoxicity. A single intraperitoneal injection of CDDP (15 mg/kg, or 25 mg/kg) deteriorated the kidney functions as reflected by histopathological changes. Histopathological changes were observed in all cisplatin groups. In the cisplatin group, oxidative stress was evident in the cisplatin group by observing an increase in 8-OHdG expression, an indicator of oxidative DNA damage. CDDP also resulted to an increase in CD68 expression in the renal tissues of CDDP groups. Taurine transporter (TauT) was down-regulated, and p53 was up-regulated in renal tissues as indicated by immunohistochemical analysis. Administration with taurine prior to a cisplatin injection was able to protect against deterioration of kidney function, to abrogate the decline in anti-oxidants and to suppress the increase in DNA damage. Moreover, taurine inhibited p53 activation and improved the pathological changes induced by cisplatin. This study demonstrates the protective effects of taurine in attenuating the expression of pro-inflammatory mediators and in improving antioxidant capacity in the kidney of cisplatin-injected rats. Thus, taurine could be a beneficial dietary supplement to attenuate cisplatin induced nephrotoxicity.

Increased Expression OF ADAMTS-13, 8-OHdG AND GFAP-NF Correlates with Neuropathology in Feline Infectious Peritonitis Virus-infected Cats

Increased Expression OF ADAMTS-13, 8-OHdG AND GFAP-NF Correlates with Neuropathology in Feline Infectious Peritonitis Virus-infected Cats

Protection of Taurine Against Arsenic-Induced DNA Damage of Mice Kidneys.

The purpose of this study was to explore the protective capacity of taurine on arsenic (As)-induced neurotoxicity. Thirty mice were used and ten rats in each group. We treated the As exposure group with 4 ppm As2O3 for 60 days by drinking water and the protective group with 4 ppm As2O3 and 150 mg/kg taurine. Drinking water was only given in the control group. Pathologic changes and DNA damage in the mice kidney were examined by HE staining, immunohistochemistry and comet assay. Abnormal morphological changes were found in the kidney of As exposed mouse. Moreover, 8-hydroxy-2-deoxyguanosine (8-OHdG) expression and comet number, tail moment, and tail length of comet were markedly elevated in the As intoxication mice. However, histopathological changes and low expression of 8-OHdG were shown in the protective group. Our results indicate that supplementation of taurine protects against the histopathologic changes and DNA damage of mouse kidneys in As exposure group.

Hyperbaric oxygen treatment reverses radiation induced pro-fibrotic and oxidative stress responses in a rat model

PurposeRadiotherapy is effective in the treatment of tumors in the pelvic area but is associated with side effects such as cystitis and proctitis. Hyperbaric Oxygen Therapy (HBOT) has emerged as a treatment modality for radiation-induced side effects. In a rat model for radiation cystitis, we studied the effects of HBOT on oxidative stress and pro-fibrotic factors. Materials and methodsSedated Sprague-Dawley rats underwent bladder irradiation of 20Gy with and without 20 sessions of HBOT during a fortnight. Control animals were treated with and without HBOT. All four groups of animals were euthanized 28 days later. Histopathological examinations, immunohistochemistry and quantitative polymerase chain reaction (qPCR) were used to analyze changes in oxidative stress (8-OHdG), anti-oxidative responses (SOD-1, SOD2, HO-1 and NRFα) and a panel of Th1-type and Th2-type cytokines (IL-1β, IL-4, IL-5, IL-6, IL-10, IL-13, TNF-α, TGF-β, IFN-γ) in the urinary bladder. ResultsBladder irradiation increased the expression of 8-OHdG, SOD2, HO-1, NRFα, IL-10, TNF-α and tended to increase TGF-β. These changes were completely reversed by HBOT while HBOT in control animals had no effects on the studied markers for oxidative stress, anti-oxidative responses and Th1-type and Th2-type cytokines. ConclusionsRadiation induced a significant elevation of oxidative stress, antioxidants and pro-fibrotic factors in our animal model for radiation cystitis that were completely reversed and normalized by HBOT. Our findings indicate that HBOT may prevent radiation-induced changes by affecting oxidative stress and inflammatory cascades induced by radiation. SummaryRadiotherapy may cause the development of chronic inflammation and fibrosis, significantly impairing organ function. We hypothesized that bladder irradiation induces an oxidative stress reaction, thereby triggering the redox system and thus initiating an inflammatory and pro-fibrotic response. We aimed to assess whether these changes would be reversed by hyperbaric oxygen using an animal model for radiation cystitis. Our study show that hyperbaric oxygen therapy may reverse oxidative stress and pro-inflammatory factors induced by radiation.

Neuroprotective effects of clarithromycin against neuronal damage in cerebral ischemia and in cultured neuronal cells after oxygen-glucose deprivation

AimsRats subjected to transient focal ischemia and cultured neuronal cells subjected to oxygen-glucose deprivation (OGD) were treated with clarithromycin (CAM) to evaluate the effects of CAM in protecting against neuronal damage. Main methodsSprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 90min and then reperfused. Each animal was given an oral dose clarithromycin (CAM, 100mg/kg) or vehicle alone just after the ischemia was commenced. The infarct volume, edema index and neurological performance were assessed after 24 and 72h of reperfusion. The cerebral blood flow (CBF) was measured with an MRI system at 90min after MCAO. After 24 and 72h, oxidative stress (4-HNE, 8-OHdG) and inflammation (Iba-1, TNF-α) were assessed by immunohistochemical analyses and degenerative cells were assessed in the cortex by Fluoro-Jade C (FJC) labeling. The cultured neuronal cells were also used to examine the effects of CAM exposure on the viability of the cells after OGD. Key findingsCBF was unchanged between the two groups. Significant reductions of the infarct volume and edema index, an improved neurological deficit score, a significant suppression of 4-HNE and 8-OHdG expression, marked reductions of Iba-1 and TNF-α expression, and a significant reduction of FJC-positive cells were also observed in the CAM-treated animals at both time points. Treatment with 10μM and 100μM CAM in vitro significantly reduced cell death after OGD. SignificanceCAM appears to provide antioxidant and anti-inflammatory effects and protect against neuronal damage after cerebral ischemia and OGD.

Novel antioxidant capability of titanium induced by UV light treatment.

The intracellular production of reactive oxygen species (ROS) is a representative form of cellular oxidative stress and plays an important role in triggering adverse cellular events, such as the inflammatory reaction and delayed or compromised differentiation. Osteoblastic reaction to titanium with particular focus on ROS production remains unknown. Ultraviolet (UV) light treatment improves the physicochemical properties of titanium, specifically the induction of super hydrophilicity and removal of hydrocarbon, and eventually enhances its osteoconductivity. We hypothesized that there is a favorable regulatory change of ROS production within osteoblasts in contact with UV-treated titanium. Osteoblasts were cultured on titanium disks with or without UV-pretreatment. The intracellular production of ROS was higher on acid-etch-created rough titanium surfaces than on machine-prepared smooth ones. The ROS production was reduced by 40-50% by UV pretreatment of titanium regardless of the surface roughness. Oxidative DNA damage, as detected by 8-OHdG expression, was alleviated by 50% on UV-treated titanium surfaces. The expression of inflammatory cytokines was consistently lower in osteoblasts cultured on UV-treated titanium. ROS scavenger, glutathione, remained more without being depleted in osteoblasts on UV-treated titanium. Bio-burden test further showed that culturing osteoblasts on UV-treated titanium can significantly reduce the ROS production even with the presence of hydrogen peroxide, an oxidative stress inducer. These data suggest that the intracellular production of ROS and relevant inflammatory reaction, which unavoidably occurs in osteoblasts in contact with titanium, can be significantly reduced by UV pretreatment of titanium, implying a novel antioxidant capability of the particular titanium.

Homocysteine Aggravates Cortical Neural Cell Injury through Neuronal Autophagy Overactivation following Rat Cerebral Ischemia-Reperfusion.

Elevated homocysteine (Hcy) levels have been reported to be involved in neurotoxicity after ischemic stroke. However, the underlying mechanisms remain incompletely understood to date. In the current study, we hypothesized that neuronal autophagy activation may be involved in the toxic effect of Hcy on cortical neurons following cerebral ischemia. Brain cell injury was determined by hematoxylin-eosin (HE) staining and TdT-mediated dUTP Nick-End Labeling (TUNEL) staining. The level and localization of autophagy were detected by transmission electron microscopy, western blot and immunofluorescence double labeling. The oxidative DNA damage was revealed by immunofluorescence of 8-Hydroxy-2′-deoxyguanosine (8-OHdG). Hcy treatment aggravated neuronal cell death, significantly increased the formation of autophagosomes and the expression of LC3B and Beclin-1 in the brain cortex after middle cerebral artery occlusion-reperfusion (MCAO). Immunofluorescence analysis of LC3B and Beclin-1 distribution indicated that their expression occurred mainly in neurons (NeuN-positive) and hardly in astrocytes (GFAP-positive). 8-OHdG expression was also increased in the ischemic cortex of Hcy-treated animals. Conversely, LC3B and Beclin-1 overexpression and autophagosome accumulation caused by Hcy were partially blocked by the autophagy inhibitor 3-methyladenine (3-MA). Hcy administration enhanced neuronal autophagy, which contributes to cell death following cerebral ischemia. The oxidative damage-mediated autophagy may be a molecular mechanism underlying neuronal cell toxicity of elevated Hcy level.

Hyperoxia disrupts the intestinal barrier in newborn rats

Animal studies have demonstrated that neonatal hyperoxia injures the distal small intestine. This study aimed to determine the effects of neonatal hyperoxia exposure on the intestinal morphology and intestinal barrier integrity in newborn rats. Sprague–Dawley rat pups were exposed to either ambient air or hyperoxia. The ambient air and normobaric hyperoxia groups were maintained in room air and 85% O2 for 2weeks, respectively. The rats were euthanized on Postnatal Day 14, and the terminal ileum was collected for histological analyses and oxidative stress measurements. The generation of reactive oxygen species was evaluated by measuring the production of 8-hydroxy-2′-deoxyguanosine (8-OHdG). The expression and localization of epithelial injury markers [intestinal fatty acid binding protein (I-FABP)] and intestinal barrier proteins [occludin and zonula occludens (ZO)-1] were analyzed through immunofluorescence staining and western blotting. The body weight at birth was comparable between the two groups. On Postnatal Day 14, the rats in the hyperoxia group exhibited significantly lower body weight, a higher serum interleukin-6 level, a higher intestinal injury score, higher 8-OHdG and I-FABP expression, and lower occludin and ZO-1 protein expression than did those in the ambient air group. Hyperoxia exposure injured the distal small intestine and disrupted the intestinal barrier in newborn rats. This may be attributable to oxidative stress during the postnatal period.

An immunohistochemical study of NFE2L2, KEAP1 and 8-hydroxy-2'-deoxyguanosine and the EMT markers SNAI2, ZEB1 and TWIST1 in metastatic melanoma.

Little is known regarding the role of redox balance regulators in metastatic melanomas, but there is some evidence for a link between epithelial-to-mesenchymal transition (EMT) and cellular redox status. We compared the immunohistochemical expression of nuclear factor erythroid-2-related factor 2 (NFE2L2), Kelch-like ECH-associated protein 1(KEAP1), 8-hydroxy-2'-deoxyguanosine (8-OHdG), TWIST1, SNAI2 and ZEB1 between primary melanomas and metastases in a cohort of 23 nevi, 66 malignant melanomas and 22 metastases. Nuclear NFE2L2 expression was higher (p=0.003) and cytoplasmic KEAP1 lower (p=0.026) in metastatic lesions than at primary sites. Nuclear NFE2L2 expression was associated with the presence of distant metastases (p=0.040) and with nuclear TWIST1 expression (p=0.002). Patients having both NFE2L2 and TWIST1 expression in nuclei had an extremely poor prognosis (p=0.0003). In multivariate analysis nuclear TWIST1 expression was an independent predictor of a poorer prognosis (HR 2.99, 95% CI 1.17-7.69; p=0.023) and the invasive TWIST1/ZEB1 phenotype showed poorer melanoma-specific survival (HR 7.28, 95% CI 2.23-23.77; p=0.001). Nuclear expression of 8-OHdG (p=0.001) was lower at metastatic sites than in primary lesions. EMT signalling and the KEAP1/NFE2L2-axis are likely to be involved in metastatic spread of malignant melanoma and also appear to have potential interactions.

Semen leukocytes and oxidative-dependent DNA damage of spermatozoa in male partners of subfertile couples with no symptoms of genital tract infection.

The influence of seminal leukocytes on generation of oxidative damage to sperm DNA was here investigated on male partners of subfertile couples asymptomatic for a genital tract infection. The study included 111 ejaculates from men attending the Andrology Centre at University of L'Aquila. Semen leukocytes subset included round cells expressing pan-leukocyte CD45 antigen, monocyte/macrophage lineage antigen CD14, and activated macrophages HLA-DR antigen. The 8-hydroxy-2'-deoxyguanosine (8-OHdG) expression identified spermatozoa with DNA oxidative adducts while terminal deoxynucleotidyl transferase (TdT)-mediated fluorescein-dUTP nick end labeling (TUNEL) assay detected spermatozoa with DNA fragmentation. Flow cytometry and immunocytochemistry was used for determinations. Main outcome measure was the association of semen leukocyte subpopulations with spermatozoa showing oxidative-related DNA damage and with routine semen parameters. Leukocyte subpopulations were strictly correlated (p<0.0001), but no association was found between the concentration of leukocytes, semen parameters, the percentage of TUNEL-positive and of 8-OHdG-positive spermatozoa. The percentage of 8-OHdG-positive spermatozoa was positively correlated with the percentage of TUNEL-positive spermatozoa (r=0.48; p<0.0001) and negatively correlated with sperm concentration (r=-0.44; p<0.0001). Sperm concentration and the percentage of TUNEL-positive spermatozoa independently contributed (β=-0.25, p=0.008; β=0.23, p=0.05, respectively) to the variation in percentage of 8-OHdG-positive spermatozoa after adjusting for age, abstinence time, and smoking. In conclusion, oxidative-dependent DNA damage in spermatozoa was associated to poor semen quality but not to different leukocyte subpopulations in ejaculates of men asymptomatic for a genital tract infection.

Placental aging and oxidation damage in a tissue micro-array model: an immunohistochemistry study.

To evaluate the expression of markers correlated with cellular senescence and DNA damage (8-hydroxy-2'-deoxy-guanosine (8-OHdG), p53, p21, APE1/Ref-1 (APE1), interleukin (IL-6 and IL-8) in placentas from healthy and pathologic pregnancies. This retrospective study considered a placental tissue micro-array containing 92 controls from different gestational ages and 158 pathological cases including preeclampsia (PE), HELLP syndrome (hemolysis, elevated liver enzymes, low platelet count), small for gestational age (SGA) fetuses, and intrauterine growth restriction (IUGR) occurring at different gestational ages. In this study, we demonstrated a significant influence of gestational age on the expression in the trophoblast of 8-OHdG, p53, p21, APE1, and IL-6. In placentas of cases affected by PE, HELLP, or IUGR, there was an increased expression of 8-OHdG, p53, APE1, and IL-6 compared to controls (only IL-8 was significantly decreased in cases). In both groups of pathology between 22- and 34-week gestation and after 34-week gestation, APE1 levels were higher in the trophoblast of women affected by hypertensive disorders of pregnancy than women carrying an IUGR fetus. The cytoplasmic expression of 8-OHdG was increased in placentas in IUGR cases compared to PE or HELLP pregnancies. In cases after 34-week gestation, p21 was higher in SGA and IUGR than in controls and late PE. Moreover, p53 was increased after 34-week gestation in IUGR pregnancies. Placentas from pathological pregnancies had an altered expression of 8-OHdG, p53, p21, APE1, IL-6, and IL-8. The alterations of intracellular pathways involving these elements may be the cause or the consequence of placental dysfunction, but in any case reflect an impaired placental function, possibly due to increased aging velocity in pathologic cases.

Protective effects of alpha lipoic acid on radiation-induced salivary gland injury in rats.

PurposeRadiation therapy is a treatment for patients with head and neck (HN) cancer. However, radiation exposure to the HN often induces salivary gland (SG) dysfunction. We investigated the effect of α-lipoic acid (ALA) on radiation-induced SG injury in rats.ResultsALA preserved acinoductal integrity and acinar cell secretary function following irradiation. These results are related to the mechanisms by which ALA inhibits oxidative stress by inhibiting gp91 mRNA and 8-OHdG expression and apoptosis of acinar cells and ductal cells by inactivating MAPKs in the early period and expression of inflammation-related factors including NF-κB, IκB-α, and TGF-β1 and fibrosis in late irradiated SG. ALA effects began in the acute phase and persisted for at least 56 days after irradiation.Materials and MethodsRats were assigned to followings: control, ALA only (100 mg/kg, i.p.), irradiated, and ALA administered 24 h and 30 min prior to irradiation. The neck area including the SG was evenly irradiated with 2 Gy per minute (total dose, 18 Gy) using a photon 6-MV linear accelerator. Rats were killed at 4, 7, 28, and 56 days after radiation.ConclusionsOur results show that ALA could be used to ameliorate radiation-induced SG injury in patients with HN cancer.

Smoking-promoted oxidative DNA damage response is highly correlated to lung carcinogenesis.

Oxidative stress induced by tobacco smoking is one of the main causes of DNA damage and is known to be involved in various cancers. Smoking is the leading cause of lung cancer, while the role of cigarette smoke-induced oxidative DNA damage response during lung carcinogenesis is largely unknown. In this study, we investigated oxidative DNA damage response levels in smoking and nonsmoking patients with lung cancer, and evaluated the potential diagnostic value of 8-OHdG for lung cancer. We observed a higher level of 8-OHdG expression and secretion in airways of lung cancer patients than that of noncancer controls. 8-OHdG expression was associated with the TNM stages. Additionally, cigarette smoke-induced oxidative DNA damage response was observed in bronchial epithelial cells in vitro and in vivo. A statistical significance correlation was found between the levels of 8-OHdG and smoking index. With a cut-off value of 2.86 ng/ml, 8-OHdG showed a sensitivity and specificity of 70.0% and 73.7%, respectively, to identify a patient with lung cancer. These findings not only underscore the importance of smoking in oxidative DNA damage response of lung cancer patients, but also suggest 8-OHdG as a potential diagnostic biomarker for lung cancer.

원지(遠志)가 뇌혈류 저하에 의한 흰쥐 뇌조직의 산화적 손상과 해마신경세포 자연사에 미치는 영향

Objectives : Polygalae Radix (POL) has an ameliorating effect on learning and memory impairment caused by cerebral hypoperfusion. In regard to POL's action mechanism, this study was carried out to investigate the effects of POL on oxidative damage and neuronal apoptosis induced by cerebral hypoperfusion in rats.Methods : The cerebral hypoperfusion was induced by permanent bilateral common carotid artery occlusion (pBCAO) in Sprague-Dawley rats. POL was administered orally once a day (130 mg/kg of water-extract) for 28 days starting at 4 weeks after the pBCAO. Superoxide dismutase (SOD) activities and malondialdehyde (MDA) levels in the brain tissue were measured using ELISA method. Expressions of 4-hydroxynonenal (4HNE) and 8-hydroxy-2'- deoxyguanosine (8-OHdG) were observed using immunohistochemistry. In addition, neuronal apoptosis was evaluated with Cresyl violet staining, TUNEL labeling, and immunohistochemistry against Bax and caspase-3.Results : POL treatment significantly increased SOD activities and significantly reduced MDA levels in the cerebral cortex. The up-regulations of 4HNE and 8-OHdG expression caused by pBCAO in the CA1 of hippocampus were significantly attenuated by POL treatment. POL treatment also restored the reduction of CA1 thickness and CA1 neurons caused by pBCAO and significantly attenuated the apoptotic markers including TUNEL-positive cells, Bax, and caspase-3 expression in the CA1 of hippocampus.Conclusions : The results show that POL attenuated the oxidative damage in brain tissue and neuronal apoptosis in the hippocampus caused by the cerebral hypoperfusion. It suggests that POL can be a beneficial medicinal herb to treat the brain diseases related to cerebral hypoperfusion.

NADPH Oxidase Inhibitor Apocynin Attenuates PCB153-Induced Thyroid Injury in Rats.

PCBs, widespread endocrine disruptors, cause the disturbance of thyroid hormone (TH) homeostasis in humans and animals. However, the exact mechanism of thyroid dysfunction caused by PCBs is still unknown. In order to clarify the hypotheses that NADPH oxidase (NOX) and subsequent NF-κB pathway may play roles in thyroid dysfunction, sixty Sprague-Dawley rats were randomly divided into four groups: control group, PCB153 treated (PCB) group, received apocynin with PCB153 treatment (APO + PCB) group, and drug control (APO) group. Serum thyroid hormone levels were evaluated. The morphological change of thyroid tissue was analyzed under the light and transmission electron microscopy. NOX2, 8-OHdG, and NF-κB expression in the thyroid tissue was evaluated by immune-histochemical staining. Oxidative stress and inflammatory cytokines were detected. The following results were reduced after apocynin treatment: (1) serum thyroid hormone, (2) thyroid pathological injuries, (3) thyroid MDA, (4) thyroid ultrastructural change, (5) serum inflammatory cytokines, and (6) thyroid expression of NOX2, 8-OHdG, and NF-κB. These results suggested that NOX inhibition attenuates thyroid dysfunction induced by PCB in rats, presumably because of its role in preventing ROS generation and inhibiting the activation of NF-κB pathway. Our findings may provide new therapeutic targets for PCBs induced thyroid dysfunction.

Molecular Hydrogen Alleviates Cellular Senescence in Endothelial Cells.

Substantial evidence indicates that molecular hydrogen (H2) has beneficial vascular effects because of its antioxidant and/or anti-inflammatory effects. Thus, hydrogen-rich water may prove to be an effective anti-aging drink. This study examined the effects of H2on endothelial senescence and clarified the mechanisms involved. Hydrogen-rich medium was produced by a high-purity hydrogen gas generator. Human umbilical vein endothelial cells (HUVECs) were incubated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for various time periods in normal or hydrogen-rich medium. The baseline H2concentration in hydrogen-rich medium was 0.55±0.07 mmol/L. This concentration gradually decreased, and H2was almost undetectable in medium after 12 h. At 24 h after TCDD exposure, HUVECs treated with TCDD exhibited increased 8OHdG and acetyl-p53 expression, decreased nicotinamide adenine dinucleotide (NAD(+))/NADH ratio, impaired Sirt1 activity, and enhanced senescence-associated β-galactosidase. However, HUVECs incubated in hydrogen-rich medium did not exhibit these TCDD-induced changes accompanying Nrf2 activation, which was observed even after H2was undetectable in the medium. Chrysin, an inhibitor of Nrf2, abolished the protective effects of H2on HUVECs. H2has long-lasting antioxidant and anti-aging effects on vascular endothelial cells through the Nrf2 pathway, even after transient exposure to H2. Hydrogen-rich water may thus be a functional drink that increases longevity. (Circ J 2016; 80: 2037-2046).