Yoon, Ji-Young; Kim, Do-Wan; Kim, Eun-Jung; Park, Bong-Soo; Yoon, Ji-Uk; Kim, Hyung-Joon; Park, Jeong-Hoon
Bone injury is common in many clinical situations, such as surgery or trauma. During surgery, excessive reactive oxygen species (ROS) production decreases the quality and quantity of osteoblasts. Remifentanil decreases ROS production, reducing oxidative stress and the inflammatory response. We investigated remifentanil's protective effects against H 2 O 2 -induced oxidative stress in osteoblasts. To investigate the effect of remifentanil on human fetal osteoblast (hFOB) cells, the cells were incubated with 1 ng/ml of remifentanil for 2 h before exposure to H 2 O 2 . For induction of oxidative stress, hFOB cells were then treated with 200 µM H 2 O 2 for 2 h. To evaluate the effect on autophagy, a separate group of cells were incubated with 1 mM 3-methyladenine (3-MA) before treatment with remifentanil and H 2 O 2 . Cell viability and apoptotic cell death were determined via MTT assay and Hoechst staining, respectively. Mineralized matrix formation was visualized using alizarin red S staining. Western blot analysis was used to determine the expression levels of bone-related genes. Cell viability and mineralized matrix formation increased on remifentanil pretreatment before exposure to H 2 O 2 -induced oxidative stress. As determined via western blot analysis, remifentanil pretreatment increased the expression of bone-related genes (Col I, BMP-2, osterix, and TGF-β). However , pretreatment with 3-MA before exposure to remifentanil and H 2 O 2 inhibited remifentanil's protective effects on hFOB cells during oxidative stress. We showed that remifentanil prevents oxidative damage in hFOB cells via a mechanism that may be highly related to autophagy. Further clinical studies are required to investigate its potential as a therapeutic agent.
Chen, Qiong-Fang; Wang, Gang; Tang, Li-Qing; Yu, Xian-Wen; Li, Zhao-Fei; Yang, Xiu-Fen
This study focuses on the protective effect of germacrone on human umbilical vein endothelial cells(HUVECs) damaged by H2O2-induced oxidative stress and its possible mechanisms. The oxidative damage model was established by using 500 μmol•L⁻¹ H2O2 to treat HUVECs for 3 hours, and then protected with different concentrations of germacrone for 24 hours. The effect of germacrone on cell viability of HUVECs damaged by H2O2 was detected by MTT. The contents of PGI2, TXB2, ET-1, t-PA, PAI-1, TNF-α and IL-6 were detected by ELISA. The content of NO was detected by using nitrate reductase method. Colorimetry was used to detect NOS and GSH-Px. The contents of MDA, SOD and LDH were detected by TBA, WST-1 and microplate respectively. Apoptosis was observed by Hoechst 33258 fluorescent staining. The mRNA expressions of Bax, Bcl-2 and Caspase-3 in cells were detected by RT-PCR. The results showed that the cell damage rate was 52% after treated with 500 μmol•L⁻¹ H2O2 for 3 hours. The cell activity was increasing with the rise of germacrone concentration within the range of 20-200 mol•L⁻¹. Compared with normal group, the contents of PGI2, NO, T-NOS, t-PA, SOD, GSH-Px and Bcl-2 mRNA expressions were lower after damaged with H2O2. The contents of PAI-1, ET-1, IL-6, TNF-α, TXB2, LDH, MDA, Bax mRNA and Caspase-3 mRNA expressions were increased. Compared with model group, the contents of PGI2, NO, T-NOS, t-PA, SOD, GSH-Px and Bcl-2 mRNA expressions were increased after treated with germacrone. The contents of PAI-1, ET-1, IL-6, TNF-α, TXB2, LDH, MDA, Bax mRNA and Caspase-3 mRNA expressions were lower after treated with germacrone. According to Hoechst 33258 fluorescence staining, compared with normal group, the cell membrane and the nucleus showed strong dense blue fluorescence, and the number of cells significantly decreased in model group. Compared with model group, blue fluorescence intensity decreased in drug group. The above findings demonstrate that
Full Text Available Objective: It has been well documented that oxidative stress is involved in the pathogenesis of cardiac diseases. Previous studies have shown that pomegranate seed oil (PSO has antioxidant properties. This study was designed to investigate probable protective effects of PSO against hydrogen peroxide (H2O2-induced damage in H9c2 cardiomyocytes.Materials and Methods: The cells were pretreated 24 hr with PSO 1 hr before exposure to 200 µM H2O2. Cell viability was evaluated using 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium (MTT assay. The level of reactive oxygen species (ROS and lipid peroxidation were measured by fluorimetric methods.Results: H2O2 significantly decreased cell viability which was accompanied by an increase in ROS production and lipid peroxidation and a decline in superoxide dismutase activity. Pretreatment with PSO increased viability of cardiomyocytes and decrease the elevated ROS production and lipid peroxidation. Also, PSO was able to restore superoxide dismutase activity.Conclusion: PSO has protective effect against oxidative stress-induced damage in cardiomyocytes and can be considered as a natural cardioprotective agent to prevent cardiovascular diseases.
Chang, Yuqian; Li, Shuli; Guo, Weinan; Yang, Yuqi; Zhang, Weigang; Zhang, Qian; He, Yuanmin; Yi, Xiuli; Cui, Tingting; An, Yawen; Song, Pu; Jian, Zhe; Liu, Ling; Li, Kai; Wang, Gang; Gao, Tianwen; Wang, Lin; Li, Chunying
The prevention of hydrogen peroxide (H2O2)-induced oxidative stress has proved to be beneficial to vitiligo patients. Simvastatin possesses antioxidative capacity and has shown protective effect in various oxidative stress-related diseases. However, whether simvastatin can protect human melanocytes against oxidative stress has not been investigated. In this study, we initially found that pretreatment with 0.1 μmol/L to 1.0 μmol/L simvastatin led to increased cell viability and decreased cell apoptosis of melanocytes in response to H2O2. In addition, simvastatin was able to potentiate the activity of antioxidant enzymes and lessen intracellular reactive oxygen species accumulation. Furthermore, we found that simvastatin promoted the activation of nuclear erythroid 2-related factor (Nrf2) and that knockdown of Nrf2 abolished the protective effect of simvastatin against H2O2-induced oxidative damage. More importantly, the mutual enhancement between mitogen-activated protein kinase pathways and p62 contributed to simvastatin-induced Nrf2 activation in melanocytes. Finally, simvastatin showed more antioxidative capacity and better protective effect than aspirin in H2O2-treated melanocytes. Taken together, our results show that simvastatin protects human melanocytes from H2O2-induced oxidative stress by activating Nrf2, thus supporting simvastatin as a potential therapeutic agent for vitiligo. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Du, Lei; Chen, Jia; Xing, Yi-Qiao
Eupatilin, a pharmacologically active flavone derived from the Artemisia plant species, is known to possess anti-oxidant activity. However, the effects of eupatilin on oxidative stress-induced retinal damage in retinal pigment epithelium (RPE) cells and the potential mechanisms involved have not been explored. Therefore, the aim of this study was to investigate the effects of eupatilin on oxidative stress-induced retinal damage in RPE cells. Our results showed that eupatilin significantly attenuated H2O2-induced cell injury and ROS production in ARPE-19 cells. In addition, eupatilin pretreatment greatly upregulated Bcl-2 expression, downregulated Bax expression, as well as suppressed caspase-3 activity in ARPE-19 cells exposed to H2O2. Furthermore, eupatilin pretreatment markedly enhanced phosphorylation levels of PI3K and Akt in ARPE-19 cells exposed to H2O2. In conclusion, our data showed that eupatilin protected against H2O2-induced oxidative stress and apoptosis through the activation of PI3K/Akt signaling pathway in ARPE-19 cells. Thus, eupatilin may be useful for the prevention or treatment of proliferative vitreoretinopathy (PVR). Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Full Text Available Apart from the antihyperglycemic effects, DPP4 inhibitors and GLP-1 molecules are involved in the preservation of cardiac functions. We have demonstrated that DPP4-deficient rats possess resistance to endotoxemia and ischemia/reperfusion stress. However, whether the decrease of DPP4 activity simply augmented the GLP-1 signaling or that such decrease resulted in a change of cellular function remain unclear. Accordingly, we investigated the responses of H(2O(2-induced oxidative stress in adult wild-type and DPP4-deficient rats isolated cardiomyocytes. The coadministration of GLP-1 or DPP4 inhibitor was also performed to define the mechanisms. Cell viability, ROS concentration, catalase activity, glucose uptake, prosurvival, proapoptotic signaling, and contractile function were examined after cells exposed to H(2O(2. DPP4-deficient cardiomyocytes were found to be resistant to H(2O(2-induced cell death via activating AKT signaling, enhancing glucose uptake, preserving catalase activity, diminishing ROS level and proapoptotic signaling. GLP-1 concentration-dependently improved cell viability in wild-type cardiomyocyte against ROS stress, and the ceiling response concentration (200 nM was chosen for studies. GLP-1 was shown to decrease H(2O(2-induced cell death by its receptor-dependent AKT pathway in wild-type cardiomyocytes, but failed to cause further activation of AKT in DPP4-deficient cardiomyocytes. Acute treatment of DPP4 inhibitor only augmented the protective effect of low dose GLP-1, but failed to alter fuel utilization or ameliorate cell viability in wild-type cardiomyocytes after H(2O(2 exposure. The improvement of cell viability after H(2O(2 exposure was correlated with the alleviation of cellular contractile dysfunction in both DPP4-deficient and GLP-1 treated wild-type cardiomyocytes. These findings demonstrated that GLP-1 receptor-dependent pathway is important and exert protective effect in wild-type cardiomyocyte. Long term loss of
Wang, Qiuju; Ju, Xue; Chen, Yuke; Dong, Xiaoqing; Luo, Sha; Liu, Hongjian; Zhang, Dongming
This study was designed in vitro to investigate the effects of L-carnitine against H2O2-induced oxidative stress in a grass carp (Ctenopharyngodon idellus) ovary cell line (GCO). GCO cells were pre-treated with different concentrations of L-carnitine, followed by incubation with 2.5 mM H2O2 for 1 h to induce oxidative damage. The results indicated that adding L-carnitine at concentrations of 0.01-1 mM into the medium for 12 h significantly increased cell viability. Pre-treatment with L-carnitine at concentrations of 0.1-5 mM for 12 h significantly inhibited 2.5 mM H2O2-induced cell viability loss. The significant decreases in the level of reactive oxygen species and cell apoptosis were observed in 0.5 mM L-carnitine group compared to the H2O2 group. Malondialdehyde values of all of the L-carnitine groups were significantly lower than those of the H2O2 group, while total glutathione levels of all of the L-carnitine groups were significantly higher than of the H2O2 group. The activity of antioxidant enzymes, such as total superoxide dismutase (0.1 and 0.5 mM L-carnitine), catalase (0.5 mM L-carnitine) and γ-glutamyl cysteine synthetase (0.5 and 1 mM L-carnitine), was significantly increased. In addition, pre-treatment of L-carnitine in GCO cells exposed to 2.5 mM H2O2 significantly increased the mRNA expression of copper, zinc superoxide dismutase, catalase (0.5 mM L-carnitine), glutamate cysteine ligase catalytic subunit (0.1-1 mM) and glutathione peroxidase (0.1 mM L-carnitine). In conclusion, L-carnitine promotes GCO cell growth and improves antioxidant function, it plays a protective role against oxidative stress induced by H2O2 in GCO cells, and the appropriate supplemental amount of L-carnitine is 0.1-1 mM.
Morabito, Rossana; Remigante, Alessia; Di Pietro, Maria Letizia; Giannetto, Antonino; La Spada, Giuseppina; Marino, Angela
Preconditioning (PC) is an adaptive response to a mild and transient oxidative stress, shown for the first time in myocardial cells and not described in erythrocytes so far. The possible adaptation of human erythrocytes to hydrogen peroxide (H2O2)-induced oxidative stress has been here verified by monitoring one of band 3 protein functions, i.e., Cl-/HCO3- exchange, through rate constant for SO4= uptake measurement. With this aim, erythrocytes were exposed to a mild and transient oxidative stress (30 min to either 10 or 100 μM H2O2), followed by a stronger oxidant condition (300- or, alternatively, 600-μM H2O2 treatment). SO4= uptake was measured by a turbidimetric method, and the possible role of catalase (CAT, significantly contributing to the anti-oxidant system in erythrocytes) in PC response has been verified by measuring the rate of H2O2 degradation. The preventive exposure of erythrocytes to 10 μM H2O2, and then to 300 μM H2O2, significantly ameliorated the rate constant for SO4= uptake with respect to 300 μM H2O2 alone, showing thus an adaptive response to oxidative stress. Our results show that (i) SO4= uptake measurement is a suitable model to monitor the effects of a mild and transient oxidative stress in human erythrocytes, (ii) band 3 protein anion exchange capability is retained after 10 μM H2O2 treatment, (iii) PC response induced by the 10 μM H2O2 pretreatment is clearly detected, and (iv) PC response, elicited by low-concentrated H2O2, is mediated by CAT enzyme and does not involve band 3 protein tyrosine phosphorylation pathways. Erythrocyte adaptation to a short-term oxidative stress may serve as a basis for future studies about the impact of more prolonged oxidative events, often associated to aging, drug consumption, chronic alcoholism, hyperglycemia, or neurodegenerative diseases.
Tian, Xing; Gao, Lingyue; An, Li; Jiang, Xiaowen; Bai, Junpeng; Huang, Jian; Meng, Weihong; Zhao, Qingchun
Compound MQA (1,5-O-dicaffeoyl-3-O-[4-malic acid methyl ester]-quinic acid) is a natural caffeoylquinic acid derivative isolated from Arctium lappa L. roots. This study aims to explore the neuroprotective effects of MQA against hydrogen peroxide (H 2 O 2 )-induced oxidative stress in SH-SY5Y neuroblastoma cells. The SH-SY5Y cells were divided into four groups, including control, 20 μM MQA, 200 μM H2O2, 200 μM H2O2 + 20 μM MQA groups. The effects of MQA on H 2 O 2 -induced cell death were measured by MTT and LDH assays. Hoechst 33342 and Annexin V-PI double staining were used to observed H2O2-induced apoptosis. Also, the effects of MQA on antioxidant system and mitochondrial pathway were explored. Further, steady-state phosphorylation levels of ERK1/2, Akt and GSK-3β were examined by Western blot analysis. Pretreatment with MQA prevented cell death in SH-SY5Y cells exposed to 200 μM H2O2 for 3 h. Meanwhile, Hoechst 33342 and Annexin V-PI double staining showed that MQA attenuated H 2 O 2 -induced apoptosis. These changes are related to elevation in SOD activity, reduction in MDA production and ROS formation, and increases in mitochondrial membrane potential (MMP). In addition, the potential mechanisms of MQA against H 2 O 2 -induced apoptosis are associated with increases in the Bcl-2/Bax ratio, decreases in cytochrome c release, caspase-3 and caspase-9 expressions, phosphorylation of ERK1/2, and dephosphorylation of AKT and GSK-3β. These findings suggest that protective effects of MQA against H 2 O 2 -induced apoptosis might be associated with mitochondrial apoptosis, ERK1/2 and AKT/GSK-3β pathway.
Liu, Xue-Ru; Cao, Lu; Li, Tao; Chen, Lin-Lin; Yu, Yi-Yan; Huang, Wen-Jun; Liu, Li; Tan, Xiao-Qiu
Previous studies have shown that propofol, an intravenous anesthetic commonly used in clinical practice, protects the myocardium from injury. Mitochondria- and endoplasmic reticulum (ER)-mediated oxidative stress and apoptosis are two important signaling pathways involved in myocardial injury and protection. The present study aimed to test the hypothesis that propofol could exert a cardio-protective effect via the above two pathways. Cultured neonatal rat cardiomyocytes were treated with culture medium (control group), H2O2 at 500 μM (H2O2 group), propofol at 50 μM (propofol group), and H2O2 plus propofol (H2O2 + propofol group), respectively. The oxidative stress, mitochondrial membrane potential (ΔΨm) and apoptosis of the cardiomyocytes were evaluated by a series of assays including ELISA, flow cytometry, immunofluorescence microscopy and Western blotting. Propofol significantly suppressed the H2O2-induced elevations in the activities of caspases 3, 8, 9 and 12, the ratio of Bax/Bcl-2, and cell apoptosis. Propofol also inhibited the H2O2-induced reactive oxygen species (ROS) generation, lactic dehydrogenase (LDH) release and mitochondrial transmembrane potential (ΔΨm) depolarization, and restored the H2O2-induced reductions of glutathione (GSH) and superoxide dismutase (SOD). In addition, propofol decreased the expressions of glucose-regulated protein 78 kDa (Grp78) and inositol-requiring enzyme 1α (IRE1α), two important signaling molecules in the ER-mediated apoptosis pathway. Propofol protects cardiomyocytes from H2O2-induced injury by inhibiting the mitochondria- and ER-mediated apoptosis signaling pathways.
Ma, Tianju; Chen, Tingjun; Li, Peng; Ye, Zi; Zhai, Wei; Jia, Liang; Chen, Wenqian; Sun, Ang; Huang, Yang; Wei, Shihui; Li, Zhaohui
This study aimed to investigate the protective role of heme oxygenase-1 (HO-1) in H2O2-induced oxidative stress and apoptosis in human lens epithelial cells (hLEC; SRA01/04). SRA01/04 cells were exposed to a hydrogen peroxide (H2O2) concentration gradient and inducers of HO-1 such as cobalt protoporphyrin (CoPP) and zinc protoporphyrin (ZnPP), respectively. In addition, an RNA silencing experiment was conducted to investigate the HO-1 function in this study. A Cell Counting Kit-8 (CCK-8) assay was used to measure cell viability. Western blot and ELISA were used to detect the level of HO-1 expression. In our study, hLECs were exposed to 400 μM hydrogen peroxide (H2O2) for 24 h with or without pretreatment with 10μΜ CoPP or 10μΜ ZnPP, respectively. Double immunofluorescence staining was used for cell identification and the qualitative expression of HO-1. Expression of HO-1 was monitored using Western blot and ELISA. Intracellular reactive oxygen species (ROS) were detected by flow cytometry analyses; commercial enzymatic kits were used to measure the levels of glutathione (GSH), as well as superoxide dismutase (SOD). The proportion of cell apoptosis was quantified by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. The expression of caspase family (-8, -3) proteins was measured by Western blot analysis. HO-1 significantly restored the cell viability under H2O2 injury via reducing the generation of ROS and increasing the levels of SOD and GSH activity. Moreover, HO-1 also inhibited H2O2-induced caspase-8 and caspase-3 proteins, thus significantly reducing the apoptosis of SRA01/04. An RNA silencing experiment demonstrated the increased resistance of LECs to oxidative stress specifically for increased levels of HO-1. These findings suggested that HO-1 protects human lens epithelial cells from H2O2-induced oxidant stress by upregulating antioxidant enzyme activity, reducing ROS generation, and thus inhibiting caspase family
Lin, Xiajing; Jiang, Shouqun; Jiang, Zongyong; Zheng, Chuntian; Gou, Zhongyong
This experiment investigated the antioxidant effects of equol on oxidative stress induced by H2O2 in chicken intestinal epithelial cells (IEC). IEC, from Lingnan yellow broiler chick embryos at embryonic day 18, were cultured in Dulbecco's modified Eagle's medium/F12. Cells were pretreated with 0, 10, 100, or 500 nM equol for 24 h before exposure to 300 μM H2O2 during a further 24 h. Oxidative damage was assessed by photomicrographs of cells, measuring cell proliferation, malondialdehyde (MDA) content, and antioxidative capacity from cellular total superoxide dismutase (T-SOD) activity, as well as the relative expressions of Nrf2, Bcl-2, SOD-1, GSH-Px3, Claudin-1 Treatment with 300 μM H2O2 caused serious damage to cells, with fewer normal intestinal epithelial cells, revealed by photomicroscopy. Treatment with 300 μM H2O2 significantly decreased live cell numbers compared with controls and prior treatment with equol had no effect in offsetting this action of H2O2 (P > 0.05). Compared with the cells treated just with H2O2, pre-treatment with 10, 100 and 500 nM equol significantly enhanced T-SOD activity (P equol before H2O2 significantly enhanced T-SOD activity compared with the untreated controls (P equol, the relative abundance of Nrf2 transcripts increased from the controls (P 0.05). Pre-treatment with 10 and 100 nM equol significantly increased the transcript abundance of Claudin-1 (P Equol is shown here to protect IECs from oxidative damage by promoting the expression of antioxidant genes, increasing the activities of antioxidant enzymes, and by enhancing antioxidant capacity; 100 nM equol appeared to be the most effective concentration. © 2016 Poultry Science Association Inc.
Ruhomally, Z; Somanah, J; Bahorun, T; Neergheen-Bhujun, V S
Morinda citrifolia L. commonly known as noni is used by the pharmaceutical and cosmetic industries due to the plethora of pharmacological activities of its metabolites. In Mauritius, the fruits of M. citrifolia are used in folk medicine against a number of indications. The present study aimed at evaluating the antioxidant activity of ripe and unripe noni fruit at both biochemical and cellular levels. Using an array of established assay systems, the fruit antioxidant propensity was assessed in terms of its radical scavenging, iron reducing and metal chelating potentials. Ascorbic acid, total phenolic and total flavonoid contents of the fruits were also determined. The ascorbic acid content of ripe noni was 76.24 ± 1.13 mg/100 g while total phenolics of ripe and unripe fruit extracts were 748.40 ± 8.85 μg and 770.34 ± 2.27 μg GAE g(-1) FW respectively. Both the ripe and unripe extracts of M. citrifolia were potent scavengers of nitric oxide, superoxide and hydroxyl radicals. The ferric reducing capacity ranged from 11.26 ± 0.33 to 11.90 ± 0.20 mM Fe(2+) g(-1) FW while the IC50 values for the iron (II) chelating power were 0.50 ± 0.01 and 1.74 ± 0.01 g FW/mL for the ripe and unripe fruit extracts respectively. Cellular studies additionally demonstrated that noni were able to dose-dependently counteract accumulation of reactive oxygen species (ROS)-induced oxidative stress, a potential obesogenic factor within human liposarcoma SW872 cells as well as significantly restore cell death within the concentration range of 0.106-0.813 g/mL. Results reported herein suggest noni as an interesting source of prophylactic antioxidants modulated by its polyphenol composition.
Jeong, Jong Hee; Noh, Min-Young; Choi, Jae-Hyeok; Lee, Haiwon; Kim, Seung Hyun
Bamboo salt (BS) and soy sauce (SS) are traditional foods in Asia, which contain antioxidants that have cytoprotective effects on the body. The majority of SS products contain high levels of common salt, consumption of which has been associated with numerous detrimental effects on the body. However, BS may be considered a healthier substitute to common salt. The present study hypothesized that SS made from BS, known as bamboo salt soy sauce (BSSS), may possess enhanced cytoprotective properties; this was evaluated using a hydrogen peroxide (H2O2)-induced neuronal cell death rat model. Rat neuronal cells were pretreated with various concentrations (0.001, 0.01, 0.1, 1 and 10%) of BSSS, traditional soy sauce (TRSS) and brewed soy sauce (BRSS), and were subsequently exposed to H2O2 (100 µM). The viability of neuronal cells, and the occurrence of DNA fragmentation, was subsequently examined. Pretreatment of neuronal cells with TRSS and BRSS reduced cell viability in a concentration-dependent manner, whereas neuronal cells pretreated with BSSS exhibited increased cell viability, as compared with non-treated neuronal cells. Furthermore, neuronal cells pretreated with 0.01% BSSS exhibited the greatest increase in viability. Exposure of neuronal cells to H2O2 significantly increased the levels of reactive oxygen species (ROS), B-cell lymphoma 2-associated X protein, poly (ADP-ribose), cleaved poly (ADP-ribose) polymerase, cytochrome c, apoptosis-inducing factor, cleaved caspase-9 and cleaved caspase-3, in all cases. Pretreatment of neuronal cells with BSSS significantly reduced the levels of ROS generated by H2O2, and increased the levels of phosphorylated AKT and phosphorylated glycogen synthase kinase-3β. Furthermore, the observed effects of BSSS could be blocked by administration of 10 µM LY294002, a phosphatidylinositol 3-kinase inhibitor. The results of the present study suggested that BSSS may exert positive neuroprotective effects against H2O2-induced cell death
Ye, Junli; Han, Yantao; Chen, Xuehong; Xie, Jing; Liu, Xiaojin; Qiao, Shunhong; Wang, Chunbo
Both oxidative stress and endoplasmic reticulum stress (ER stress) have been linked to pathogenesis of neurodegenerative diseases. Our previous study has shown that L-carnitine may function as an antioxidant to inhibit H2O2-induced oxidative stress in neuroblastoma SH-SY5Y cells. To further explore the neuroprotection of L-carnitine, here we study the effects of L-carnitine on the ER stress response in H2O2-induced SH-SY5Y cell injury. Our results showed that L-carnitine pretreatment could increase cell viability; inhibit apoptosis and ROS accumulation caused by H2O2 or tunicamycin (TM). L-carnitine suppress the endoplasmic reticulum dilation and activation of ER stress-associated proteins including glucose-regulated protein 78 (GRP78), CCAAT/enhancer-binding protein-homologous protein (CHOP), JNK, Bax and Bim induced by H2O2 or TM. In addition, H2O2-induced cell apoptosis and activation of ER stress can also be attenuated by antioxidant N-acetylcysteine (NAC), CHOP siRNA and the inhibitor of ER stress 4-phenylbutyric acid (4-PBA). Taken together, our results demonstrated that H2O2 could trigger both oxidative stress and ER stress in SH-SY5Y cells, and ER stress participated in SH-SY5Y apoptosis mediated by H2O2-induced oxidative stress. CHOP/Bim or JNK/Bim-dependent ER stress signaling pathways maybe related to the neuroprotective effects of L-carnitine against H2O2-induced apoptosis and oxidative injury. Copyright © 2014 Elsevier Ltd. All rights reserved.
Alnuqaydan, Abdullah M; Lenehan, Claire E; Hughes, Rachel R; Sanderson, Barbara J
The in vitro safety and antioxidant potential of Calendula officinalis flower head extracts was investigated. The effect of different concentrations (0.125, 0.5, 1.0, 2.0 and 5.0% (v/v)) of Calendula extracts on human skin cells HaCaT in vitro was explored. Doses of 1.0% (v/v) (0.88 mg dry weight/mL) or less showed no toxicity. Cells were also exposed to the Calendula extracts for either 4, 24 or 48 h before being exposed to an oxidative insult (hydrogen peroxide H2 O2 ) for 1 h. Using the MTT cytotoxicity assay, it was observed that two independent extracts of C. officinalis gave time-dependent and concentration-dependent H2 O2 protection against induced oxidative stress in vitro using human skin cells. Pre-incubation with the Calendula extracts for 24 and 48 h increased survival relative to the population without extract by 20% and 40% respectively following oxidative challenge. The antioxidant potential of the Calendula extracts was confirmed using a complimentary chemical technique, the DPPH(●) assay. Calendula extracts exhibited free radical scavenging abilities. This study demonstrates that Calendula flower extracts contain bioactive and free radical scavenging compounds that significantly protect against oxidative stress in a human skin cell culture model. Copyright © 2014 John Wiley & Sons, Ltd.
Full Text Available Gardenamide A (GA protects the rat retinal ganglion (RGC-5 cells against cell apoptosis induced by H2O2. The protective effect of GA was completely abrogated by the specific phosphoinositide 3-kinase (PI3K inhibitor LY294002, and the specific protein kinase B (Akt inhibitor Akt VIII respectively, indicating that the protective mechanism of GA is mediated by the PI3K/Akt signaling pathway. The specific extracellular signal-regulated kinase (ERK1/2 inhibitor PD98059 could not block the neuroprotection of GA. GA attenuated the levels of reactive oxygen species (ROS and malondialdehyde (MDA induced by H2O2. Western blotting showed that GA promoted the phosphorylation of ERK1/2, Akt and endothelial nitric oxide synthase (eNOS, respectively, and effectively reversed the H2O2-inhibited phosphorylation of these three proteins. LY294002 completely inhibited the GA-activated phosphorylation of Akt, while only partially inhibiting eNOS. This evidence implies that eNOS may be activated directly by GA. PD98059 attenuated only partially the GA-induced phosphorylation of ERK1/2 with/without the presence of H2O2, indicating that GA may activate ERK1/2 directly. All these results put together confirm that GA protects RGC-5 cells from H2O2 insults via the activation of PI3K/Akt/eNOS signaling pathway. Whether the ERK1/2 signaling pathway is involved requires further investigations.
Gao, Shasha; Qin, Tingyu; Liu, Zhenzhen; Caceres, Maria Andrea; Ronchi, Carlos F.; Chen, C-Y. Oliver; Yeum, Kyung-jin; Taylor, Allen; Blumberg, Jeffery B.; Liu, Yizhi
Purpose Epidemiological studies suggest that dietary intake of lutein and zeaxanthin is inversely related to the risk for senile cataract. The objectives of this work were to investigate the mechanisms by which these nutrients provide anti-cataract effects. We evaluated their modulation of oxidative damage in human lens epithelial cells (HLEC) and their interaction with intracellular glutathione (GSH). Methods Subconfluent HLEC were pre-incubated with or without 5 µM lutein, zeaxanthin, or α-tocopherol for 48 h and then exposed to 100 µM H2O2 for 1 h. Levels of protein carbonyls in the cells were measured by western-blotting analysis following reaction with 2,4-dinitrophenylhydrazine (DNPH). Levels of malondialdehyde (MDA), reduced glutathione (GSH) and oxidized glutathione (GSSG) were measured by an HPLC system. DNA damage was assessed using comet assays. Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Results In the absence of H2O2, HLEC had very low levels of protein carbonyl and MDA. Supplementation with lutein, zeaxanthin, or α-tocopherol to the unstressed HLEC had no detectable effects on levels of oxidized proteins and lipid in the cells. Exposure of HLEC to H2O2 significantly increased levels of oxidized proteins, lipid peroxidation, and DNA damage. Pre-incubation with lutein, zeaxanthin, or α-tocopherol dramatically reduced the levels of H2O2 -induced protein carbonyl, MDA, and DNA damage in HLEC. The protective effects of lutein, zeaxanthin, and α-tocopherol against protein oxidation, lipid peroxidation, and DNA damage were comparable. Supplementation with lutein, zeaxanthin, or α-tocopherol increased GSH levels and GSH:GSSG ratio, particularly in response to oxidative stress. Depletion of GSH resulted in significant increase in susceptibility to H2O2-induced cell death. Supplementation with α-tocopherol, but not lutein or zeaxanthin, can partially restore the
Saleem Bani Hani
Conclusions: The results from this study suggest that the water-soluble extract of S. fruticosa leaves protects against both H2O2-induced and intrinsic cellular DNA oxidation in human embryonic kidney 293 cells.
Xu, Yihui; Lin, Wei; Ye, Shuifen; Wang, Huajin; Wang, Tingting; Su, Youyan; Wu, Liangning; Wang, Yuanwang; Xu, Qian; Xu, Chuanshan; Cai, Jing
Oxidative damage plays a critical role in the etiology of neurodegenerative disorders including Parkinson's disease (PD). In our study, an ancient Chinese kidney-tonifying formula, which consists of Cistanche, Epimedii, and Polygonatum cirrhifolium, was investigated to protect MES23.5 dopaminergic neurons against hydrogen peroxide- (H2O2-) induced oxidative damage. The damage effects of H2O2 on MES23.5 cells and the protective effects of KTF against oxidative stress were evaluated using MTT assay, transmission electron microscopy (TEM), immunocytochemistry (ICC), enzyme-linked immunosorbent assay (ELISA), and immunoblotting. The results showed that cell viability was dramatically decreased after a 12 h exposure to 150 μM H2O2. TEM observation found that the H2O2-treated MES23.5 cells presented cellular organelle damage. However, when cells were incubated with KTF (3.125, 6.25, and 12.5 μg/ml) for 24 h after H2O2 exposure, a significant protective effect against H2O2-induced damage was observed in MES23.5 cells. Using ICC, we found that KTF inhibited the reduction of the tyrosine hydroxylase (TH) induced by H2O2, upregulated the mRNA and protein expression of HO-1, CAT, and GPx-1, and downregulated the expression of caspase 3. These results indicated that KTF may provide neuron protection against H2O2-induced cell damage through ameliorating oxidative stress, and our findings provide a new potential strategy for the prevention and treatment of Parkinson's disease.
Li, Kai; Shen, Qingyi; Xie, Youtao; You, Mingyu; Huang, Liping; Zheng, Xuebin
Oxidative stress exerts a key influence in osteoporosis in part by inhibiting osteogenic differentiation of bone marrow stromal cells (BMSCs). With their unique antioxidant properties and reported biocompatibility, cerium oxide (CeO 2 ) ceramics exhibit promising potential for the treatment of osteoporosis resulting from oxidative stress. In this study, protective effects of CeO 2 -incorporated hydroxyapatite coatings (HA-10Ce and HA-30Ce) on the viability and osteogenic differentiation of H 2 O 2 -treated BMSCs were examined. CeO 2 -incorporated HA coatings enhanced cell viability and attenuated cell apoptosis caused by H 2 O 2 . An increase in CeO 2 content in HA coatings better alleviated H 2 O 2 -induced inhibition of osteogenic differentiation by increasing alkaline phosphatase (ALP) activity, calcium deposition activity, and mRNA expression levels of osteogenesis markers runt-related transcription factor 2 (Runx2), ALP, and osteocalcin (OCN) in BMSCs. Furthermore, the H 2 O 2 -induced decrease of gene and protein expressions of β-catenin and cyclin D1 in the Wnt/β-catenin signaling pathway was successfully rescued by the CeO 2 incorporated HA coatings. Besides, the decreased expression of receptor activator of nuclear factor kappa-B ligand (RANKL) and the increased ratio of osteoprotegerin (OPG)/RANKL in BMSCs on the CeO 2 -modified coatings was observed, indicating the inhibition of osteoclastogenesis. The above results were mediated by the antioxidant properties of CeO 2 . The CeO 2 -incorporated HA coatings reversed the decreased superoxide dismutase (SOD) activity, reduced reactive oxygen species (ROS) generation, and suppressed the malondiadehyde (MDA) formation. The findings suggested that CeO 2 -modified HA coatings may be promising coating materials for osteoporotic bone regeneration.
Ding, Xiao; Wang, Dian; Li, Longlong; Ma, Haitian
Dehydroepiandrosterone (DHEA) is widely used as a nutritional supplement, and administration of DHEA produces a number of beneficial effects in the elderly. Many researchers have suggested that DHEA exerts it function after conversion into more biologically active hormones in peripheral target cells. The actions of DHEA in Leydig cells, a major target cell of DHEA biotransformation in males, are not clear. The present study found that DHEA increased cell viability and decreased reactive oxygen species (ROS) and malondialdehyde contents in H2O2-induced Leydig cells. DHEA significantly increased the activities of superoxide dismutase, catalase and peroxidase, and decreased the DNA damage in H2O2-induced Leydig cells. Apoptosis was significant decreased in H2O2-induced Leydig cells after DHEA treatment. DHEA inhibited the loss of mitochondrial membrane potential (ΔΨm) and the upregulation of the caspase-3 protein level induced by H2O2 in Leydig cells. DHEA also reversed the decrease in PI3K and p-Akt protein levels induced by H2O2. These data showed that DHEA could ameliorate H2O2-induced oxidative damage by increasing anti-oxidative enzyme activities, which resulted in reduced ROS content, and decreased apoptosis, mainly by preventing the loss of ΔΨm and inhibiting caspase-3 protein levels via activation of PI3K/Akt signaling pathways. These results increase our understanding of the molecular mechanism of the anti-ageing effect of DHEA. Copyright © 2015 Elsevier Ltd. All rights reserved.
Full Text Available Buchang naoxintong capsule (BNC is a traditional Chinese medicine approved for the treatment of cerebrovascular and cardiovascular diseases. However, little is known about the specific protective function or mechanism by which BNC protects against myocardial injury. This research was designed to investigate the cardioprotective effects of BNC in vitro model of hydrogen peroxide (H2O2-induced H9c2 rat cardiomyoblasts. BNC intestinal absorption liquid was used in this study instead of drug-containing serum or extracting solution. Our study revealed that BNC preconditioning enhanced antioxidant function by increasing the activities of total-antioxygen capacity, total-superoxide dismutase, and catalase and by decreasing the production of reactive oxygen species and malondialdehyde. BNC preconditioning also activated extracellular signal-regulated kinases (ERK1/2 and inhibited apoptosis-related proteins such as poly ADP-ribose polymerase (PARP and caspase-3. Additionally, preincubation with BNC reduced intracellular Ca2+ concentration, improved mitochondrial membrane potential, and decreased the apoptosis rate of H9c2 cells in a dose-dependent manner. These data demonstrated that BNC protects H9c2 cardiomyoblasts from H2O2-induced oxidative injury by increasing antioxidant abilities, activating ERK1/2, and blocking Ca2+-dependent and mitochondria-mediated apoptosis. Based on our results, the potency of BNC for protecting H9c2 cells from oxidative damage is comparable to that of trimetazidine.
Full Text Available Selenium- (Se- enriched polysaccharide SPMP-2a was extracted and purified from Pleurotus geesteranus. SPMP-2a is a white flocculent polysaccharide and soluble in water, with a molecular weight of 3.32 × 104 Da. Fourier transform infrared spectroscopy spectral analysis indicated that it belongs to an acid Se polysaccharide with α-D-glucopyranoside bond. The effects of Se polysaccharide SPMP-2a in P. geesteranus against hydrogen peroxide- (H2O2- induced oxidative damage in human keratinocytes (HaCaT cells were evaluated further. Reduced cell viability and elevated apoptotic rates in H2O2-treated HaCaT cells were proven by MTT and flow cytometry assays. Hoechst 33342 staining revealed chromatin condensations in the nuclei of HaCaT cells. However, with the addition of SPMP-2a, cell viability improved, nuclear condensation declined, and cell apoptotic rates dropped significantly. Ultrastructural observation consistently revealed that treatments with SPMP-2a reduced the number of swollen and vacuolar mitochondria in the H2O2-treated cells compared with the controls. Furthermore, SPMP-2a increased the superoxide dismutase (SOD and catalase (CAT activities and reduced reactive oxygen species (ROS content. Western blot analysis showed that SPMP-2a treatment effectively increased B-cell lymphoma 2 (Bcl-2 protein expression. Therefore, SPMP-2a could improve cellular antioxidant enzyme activities, reduce ROS levels, and increase Bcl-2 protein expression levels, thereby reducing cell apoptosis and protecting HaCaT cells from H2O2-induced oxidative damage.
Full Text Available Glutamine is the most abundant free amino acid in the human blood stream and is 'conditionally essential' to cells. Its intracellular levels are regulated both by the uptake of extracellular glutamine via specific transport systems and by its intracellular synthesis by glutamine synthetase (GS. Adding to the regulatory complexity, when extracellular glutamine is reduced GS protein levels rise. Unfortunately, this excess GS can be maladaptive. GS overexpression is neurotoxic especially if the cells are in a low-glutamine medium. Similarly, in low glutamine, the levels of multiple stress response proteins are reduced rendering cells hypersensitive to H(2O(2, zinc salts and DNA damage. These altered responses may have particular relevance to neurodegenerative diseases of aging. GS activity and glutamine levels are lower in the Alzheimer's disease (AD brain, and a fraction of AD hippocampal neurons have dramatically increased GS levels compared with control subjects. We validated the importance of these observations by showing that raising glutamine levels in the medium protects cultured neuronal cells against the amyloid peptide, Aβ. Further, a 10-day course of dietary glutamine supplementation reduced inflammation-induced neuronal cell cycle activation, tau phosphorylation and ATM-activation in two different mouse models of familial AD while raising the levels of two synaptic proteins, VAMP2 and synaptophysin. Together, our observations suggest that healthy neuronal cells require both intracellular and extracellular glutamine, and that the neuroprotective effects of glutamine supplementation may prove beneficial in the treatment of AD.
Leong, Sze Ying; Oey, Indrawati; Burritt, David John
This research aimed to study the effect of pulsed electric field (PEF) processing on the bioprotective capacity of carrot purée for White Belgian, Yellow Solar, Nantes, Nutri Red and Purple Haze cultivars against H2O2-induced oxidative damage. The bioprotective capacity was determined using cell viability, membrane integrity and nitric oxide (NO) production in a human Caco-2 cell culture assay. Total carotenoids, total anthocyanins, total vitamin C and total phenolics were also evaluated. Compared to the untreated purée, Purple Haze and Nutri Red processed at 303 kJ/kg completely increased Caco-2 cells resistance towards oxidative damage by recovering the cell viability and inhibiting NO production. For cultivar with low carotenoid levels, i.e. Yellow Solar, the application of 0.8 kV/cm resulted in a higher total carotenoid content in the purée than its untreated counterpart, leading to an improved bioprotective effect. This study clearly shows that PEF could add value to carrots by maximising bioprotective effects. Copyright © 2015 Elsevier Ltd. All rights reserved.
Full Text Available Proanthocyanidins (PCs have shown inhibition of oxidative damage by improving Nrf-2 expression in many tissues. However, the cytoprotective effects of PCs on H2O2-induced tendon damage have not been verified. The current study was aimed at assessing the cytoprotection of PCs on the oxidative cellular toxicity of tendon-derived stem cells (TDSCs induced by H2O2. The TDSCs were isolated from patellar tendons of Sprague Dawley (SD rats, and the cells after third passage were used for subsequent experiments. The isolated cells were identified by flow cytometry assay and multidifferentiation potential assay. Cell Counting Kit-8 assay was performed to examine cell viability. Real-Time PCR and Western Blot were employed to, respectively, assess the mRNA and protein expressions of Nrf-2, GCLM, NQO-1, and HO-1. PCs significantly improved the cell viability of TDSCs. Furthermore, H2O2 upregulated Nrf-2, GCLM, NQO-1, and HO-1 without significant difference, while the proteins expressions were increased with significant difference in PCs group and PCs + H2O2 cotreated group. All the findings indicated that PCs could protect against the oxidative damage induced by H2O2 in TDSCs, and the cytoprotective effects might be due to the ability of PCs to activate the expressions of GCLM, HO-1, and NQO-1 via upregulating Nrf-2 signaling pathway.
Su, Hua; Liu, Dan-Dan; Zhao, Meng; Hu, Wei-Liang; Xue, Shan-Shan; Cao, Qian; Le, Xue-Yi; Ji, Liang-Nian; Mao, Zong-Wan
Polyvinylpyrrolidone-stabilized iridium nanoparticles (PVP-IrNPs), synthesized by the facile alcoholic reduction method using abundantly available PVP as protecting agents, were first reported as enzyme mimics showing intrinsic catalase- and peroxidase-like activities. The preparation procedure was much easier and more importantly, kinetic studies found that the catalytic activity of PVP-IrNPs was comparable to previously reported platinum nanoparticles. Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) characterization indicated that PVP-IrNPs had the average size of approximately 1.5 nm and mainly consisted of Ir(0) chemical state. The mechanism of PVP-IrNPs' dual-enzyme activities was investigated using XPS, Electron spin resonance (ESR) and cytochrome C-based electron transfer methods. The catalase-like activity was related to the formation of oxidized species Ir(0)@IrO2 upon reaction with H2O2. The peroxidase-like activity originated from their ability acting as electron transfer mediators during the catalysis cycle, without the production of hydroxyl radicals. Interestingly, the protective effect of PVP-IrNPs against H2O2-induced cellular oxidative damage was investigated in an A549 lung cancer cell model and PVP-IrNPs displayed excellent biocompatibility and antioxidant activity. Upon pretreatment of cells with PVP-IrNPs, the intracellular reactive oxygen species (ROS) level in response to H2O2 was decreased and the cell viability increased. This work will facilitate studies on the mechanism and biomedical application of nanomaterials-based enzyme mimic.
Full Text Available Salidroside (SAL is an active component of Rhodiola rosea with documented antioxidative properties. The purpose of this study is to explore the mechanism of the protective effect of SAL on hydrogen peroxide- (H2O2- induced endothelial dysfunction. Pretreatment of the human umbilical vein endothelial cells (HUVECs with SAL significantly reduced the cytotoxicity brought by H2O2. Functional studies on the rat aortas found that SAL rescued the endothelium-dependent relaxation and reduced superoxide anion (O2∙- production induced by H2O2. Meanwhile, SAL pretreatment inhibited H2O2-induced nitric oxide (NO production. The underlying mechanisms involve the inhibition of H2O2-induced activation of endothelial nitric oxide synthase (eNOS, adenosine monophosphate-activated protein kinase (AMPK, and Akt, as well as the redox sensitive transcription factor, NF-kappa B (NF-κB. SAL also increased mitochondrial mass and upregulated the mitochondrial biogenesis factors, peroxisome proliferator-activated receptor gamma-coactivator-1alpha (PGC-1α, and mitochondrial transcription factor A (TFAM in the endothelial cells. H2O2-induced mitochondrial dysfunction, as demonstrated by reduced mitochondrial membrane potential (Δψm and ATP production, was rescued by SAL pretreatment. Taken together, these findings implicate that SAL could protect endothelium against H2O2-induced injury via promoting mitochondrial biogenesis and function, thus preventing the overactivation of oxidative stress-related downstream signaling pathways.
Xing, Shasha; Yang, Xiaoyan; Li, Wenjing; Bian, Fang; Wu, Dan; Chi, Jiangyang; Xu, Gao; Zhang, Yonghui; Jin, Si
Salidroside (SAL) is an active component of Rhodiola rosea with documented antioxidative properties. The purpose of this study is to explore the mechanism of the protective effect of SAL on hydrogen peroxide- (H2O2-) induced endothelial dysfunction. Pretreatment of the human umbilical vein endothelial cells (HUVECs) with SAL significantly reduced the cytotoxicity brought by H2O2. Functional studies on the rat aortas found that SAL rescued the endothelium-dependent relaxation and reduced superoxide anion (O2∙−) production induced by H2O2. Meanwhile, SAL pretreatment inhibited H2O2-induced nitric oxide (NO) production. The underlying mechanisms involve the inhibition of H2O2-induced activation of endothelial nitric oxide synthase (eNOS), adenosine monophosphate-activated protein kinase (AMPK), and Akt, as well as the redox sensitive transcription factor, NF-kappa B (NF-κB). SAL also increased mitochondrial mass and upregulated the mitochondrial biogenesis factors, peroxisome proliferator-activated receptor gamma-coactivator-1alpha (PGC-1α), and mitochondrial transcription factor A (TFAM) in the endothelial cells. H2O2-induced mitochondrial dysfunction, as demonstrated by reduced mitochondrial membrane potential (Δψm) and ATP production, was rescued by SAL pretreatment. Taken together, these findings implicate that SAL could protect endothelium against H2O2-induced injury via promoting mitochondrial biogenesis and function, thus preventing the overactivation of oxidative stress-related downstream signaling pathways. PMID:24868319
Full Text Available Aim: Copaene (COP, a tricyclic sesquiterpene, is present in several essential oils of medicinal and aromatic plants and has antioxidant and anticarcinogenic features. But, very little information is known about the effects of COP on oxidative stress induced neurotoxicity. Method: We used hydrogen peroxide (H2O2 exposure for 6 h to model oxidative stress. Therefore, this experimental design allowed us to explore the neuroprotective potential of COP in H2O2-induced toxicity in rat cerebral cortex cell cultures for the first time. For this purpose, methyl thiazolyl tetrazolium (MTT and lactate dehydrogenase (LDH release assays were carried out to evaluate cytotoxicity. Total antioxidant capacity (TAC and total oxidative stress (TOS parameters were used to evaluate oxidative changes. In addition to determining of 8-hydroxy-2-deoxyguanosine (8-OH-dG levels, the single cell gel electrophoresis (SCGE or comet assay was also performed for measuring the resistance of neuronal DNA to H2O2-induced challenge. Result: The results of this study showed that survival and TAC levels of the cells decreased, while TOS, 8-OH-dG levels and the mean values of the total scores of cells showing DNA damage increased in the H2O2 alone treated cultures. But pre-treatment of COP suppressed the cytotoxicity, genotoxicity and oxidative stress which were increased by H2O2. Conclusion: It is proposed that COP as a natural product with an antioxidant capacity in mitigating oxidative injuries in the field of neurodegenerative diseases. [J Intercult Ethnopharmacol 2014; 3(1.000: 21-28
Luo, Fenglei; Lv, Qiang; Zhao, Yuqin; Hu, Guibing; Huang, Guodi; Zhang, Jiukai; Sun, Chongde; Li, Xian; Chen, Kunsong
Mangiferin is a natural xanthonoid with various biological activities. Quantification of mangiferin in fruit peel, pulp, and seed kernel was carried out in 11 Chinese mango (Mangifera indica L.) cultivars. The highest mangiferin content was found in the peel of Lvpimang (LPM) fruit (7.49 mg/g DW). Efficient purification of mangiferin from mango fruit peel was then established for the first time by combination of macroporous HPD100 resin chromatography with optimized high-speed counter-current chromatography (HSCCC). Purified mangiferin was identified by both HPLC and LC-MS, and it showed higher DPPH(•) free-radical scavenging capacities and ferric reducing ability of plasma (FRAP) than by l-ascorbic acid (Vc) or Trolox. In addition, it showed significant protective effects on human umbilical vein endothelial cells (HUVEC) under H(2)O(2)-induced stress. Cells treated with mangiferin resulted in significant enhanced cell survival under of H(2)O(2) stress. Therefore, mangiferin from mango fruit provides a promising perspective for the prevention of oxidative stress-associated diseases.
Luo, Fenglei; Lv, Qiang; Zhao, Yuqin; Hu, Guibing; Huang, Guodi; Zhang, Jiukai; Sun, Chongde; Li, Xian; Chen, Kunsong
Mangiferin is a natural xanthonoid with various biological activities. Quantification of mangiferin in fruit peel, pulp, and seed kernel was carried out in 11 Chinese mango (Mangifera indica L.) cultivars. The highest mangiferin content was found in the peel of Lvpimang (LPM) fruit (7.49 mg/g DW). Efficient purification of mangiferin from mango fruit peel was then established for the first time by combination of macroporous HPD100 resin chromatography with optimized high-speed counter-current chromatography (HSCCC). Purified mangiferin was identified by both HPLC and LC-MS, and it showed higher DPPH• free-radical scavenging capacities and ferric reducing ability of plasma (FRAP) than by l-ascorbic acid (Vc) or Trolox. In addition, it showed significant protective effects on human umbilical vein endothelial cells (HUVEC) under H2O2-induced stress. Cells treated with mangiferin resulted in significant enhanced cell survival under of H2O2 stress. Therefore, mangiferin from mango fruit provides a promising perspective for the prevention of oxidative stress-associated diseases. PMID:23109851
Nikdel, K; Aminafshar, M; Mohammadi-Sangcheshmeh, A; EmamJomeh-Kashan, N; Seyedjafari, E
In this study, in vitro maturation was performed in presence of various concentrations (0, 10, 100, or 1000 µM) of H2O2. The intracellular glutathione (GSH) level, fertilization, cleavage, and blastocyst rates, total cell number, and apoptotic cell number and expression of Bax, Bcl-2, and p53 genes in blastocyst-stage embryos were studied. At 10 μM H2O2 concentration, a higher GSH level was detected in comparison to the other groups while oocytes exposed to 1000 μM H2O2 had the lowest GSH level. Treatment of oocytes with 1000 μM H2O2 decreased the rate of two pronuclei formation as compared with other groups. A higher rate of blastocyst formation was seen in 100 μM H2O2 group as compared with the control group. However, exogenous H2O2 in maturation medium did not affect total cell numbers and apoptotic cell ratio at the blastocyst stage. Moreover, mRNA transcript abundance of Bax, Bcl-2, and p53 genes was similar between blastocysts derived from H2O2-induced oocytes and control blastocysts. Treatment of oocytes with H2O2 at mild level during in vitro maturation had a positive effect on GSH level and this, in turn, may lead to improvement in preimplantation embryonic development.
Zhuang, Yongliang; Ma, Qingyu; Guo, Yan; Sun, Liping
Rambutan peel phenolic (RPP) extracts were prepared via dynamic separation with macroporous resin. The total phenolic content and individual phenolics in RPP were determined. Results showed that the total phenolic content of RPP was 877.11 mg gallic acid equivalents (GAE)/g extract. The content of geranin (122.18 mg/g extract) was the highest among those of the 39 identified phenolic compounds. RPP protected against oxidative stress in H 2 O 2 -induced HepG2 cells in a dose-response manner. The inhibitory effects of RPP on cell apoptosis might be related to its inhibitory effects on the generation of intracellular reactive oxygen species and increased effects on superoxide dismutase activity. The in vivo anti-aging activity of RPP was evaluated using an aging mice model that was induced by d-galactose (d-gal). The results showed that RPP enhanced the antioxidative status of experimental mice. Moreover, histological analysis indicated that RPP effectively reduced d-gal-induced liver and kidney tissue damage in a dose-dependent manner. Therefore, RPP can be used as a natural antioxidant and anti-aging agent in the pharmaceutical and food industries. Copyright © 2017 Elsevier Ltd. All rights reserved.
Yoon, Ji-Young; Park, Jeong-Hoon; Kim, Eun-Jung; Park, Bong-Soo; Yoon, Ji-Uk; Shin, Sang-Wook; Kim, Do-Wan
Reactive oxygen species play critical roles in homeostasis and cell signaling. Dexmedetomidine, a specific agonist of the α2-adrenoceptor, has been commonly used for sedation, and it has been reported to have a protective effect against oxidative stress. In this study, we investigated whether dexmedetomidine has a protective effect against H2O2-induced oxidative stress and the mechanism of H2O2-induced cell death in normal human fetal osteoblast (hFOB) cells. Cells were divided into three groups: control group-cells were incubated in normoxia without dexmedetomidine, hydrogen peroxide (H2O2) group-cells were exposed to H2O2 (200 µM) for 2 h, and Dex/H2O2 group-cells were pretreated with dexmedetomidine (5 µM) for 2 h then exposed to H2O2 (200 µM) for 2 h. Cell viability and apoptosis were evaluated. Osteoblast maturation was determined by assaying bone nodular mineralization. Expression levels of bone-related proteins were determined by western blot. Cell viability was significantly decreased in the H2O2 group compared with the control group, and this effect was improved by dexmedetomidine. The Hoechst 33342 and Annexin-V FITC/PI staining revealed that dexmedetomidine effectively decreased H2O2-induced hFOB cell apoptosis. Dexmedetomidine enhanced the mineralization of hFOB cells when compared to the H2O2 group. In western blot analysis, bone-related protein was increased in the Dex/H2O2 group. We demonstrated the potential therapeutic value of dexmedetomidine in H2O2-induced oxidative stress by inhibiting apoptosis and enhancing osteoblast activity. Additionally, the current investigation could be evidence to support the antioxidant potential of dexmedetomidine in vitro.
Yu, Jie; Lin, Jia-Jia; Yu, Rui; He, Shan; Wang, Qin-Wen; Cui, Wei; Zhang, Jin-Rong
Background: As a natural carotenoid abundant in chloroplasts of edible brown algae, fucoxanthin possesses various health benefits, including anti-oxidative activity in particular. Objective: In the present study, we studied whether fucoxanthin protected against hydrogen peroxide (H2O2)-induced neuronal apoptosis. Design: The neuroprotective effects of fucoxanthin on H2O2-induced toxicity were studied in both SH-SY5Y cells and primary cerebellar granule neurons. Results: Fucoxanthin significantly protected against H2O2-induced neuronal apoptosis and intracellular reactive oxygen species. H2O2 treatment led to the reduced activity of phosphoinositide 3-kinase (PI3-K)/Akt cascade and the increased activity of extracellular signal-regulated kinase (ERK) pathway in SH-SY5Y cells. Moreover, fucoxanthin significantly restored the altered activities of PI3-K/Akt and ERK pathways induced by H2O2. Both specific inhibitors of glycogen synthase kinase 3β (GSK3β) and mitogen-activated protein kinase kinase (MEK) significantly protected against H2O2-induced neuronal death. Furthermore, the neuroprotective effects of fucoxanthin against H2O2-induced neuronal death were abolished by specific PI3-K inhibitors. Conclusions: Our data strongly revealed that fucoxanthin protected against H2O2-induced neurotoxicity via concurrently activating the PI3-K/Akt cascade and inhibiting the ERK pathway, providing support for the use of fucoxanthin to treat neurodegenerative disorders induced by oxidative stress.
Gechev, Tsanko; Mehterov, Nikolay; Denev, Iliya; Hille, Jacques
A genetic approach is described to isolate mutants more tolerant to oxidative stress. A collection of T-DNA activation tag Arabidopsis thaliana mutant lines was screened for survivors under conditions that trigger H2O2-induced cell death. Oxidative stress was induced by applying the catalase (CAT)
Shimizu, Shunichi; Yonezawa, Ryo; Negoro, Takaharu; Yamamoto, Shinichiro; Numata, Tomohiro; Ishii, Masakazu; Mori, Yasuo; Toda, Takahiro
Transient receptor potential melastatin 2 (TRPM2) is an oxidative stress-sensitive Ca(2+)-permeable channel. In monocytes/macrophages, H2O2-induced TRPM2 activation causes cell death and/or production of chemokines that aggravate inflammatory diseases. However, relatively high concentrations of H2O2 are required for activation of TRPM2 channels in vitro. Thus, in the present study, factors that sensitize TRPM2 channels to H2O2 were identified and subsequent physiological responses were examined in U937 human monocytes. Temperature increase from 30°C to 37°C enhanced H2O2-induced TRPM2-mediated increase in intracellular free Ca(2+) ([Ca(2+)]i) in TRPM2-expressing HEK 293 cells (TRPM2/HEK cells). The H2O2-induced TRPM2 activation enhanced by the higher temperature was dramatically sensitized by intracellular Fe(2+)-accumulation following pretreatment with FeSO4. Thus intracellular Fe(2+)-accumulation sensitizes H2O2-induced TRPM2 activation at around body temperature. Moreover, intracellular Fe(2+)-accumulation increased poly(ADP-ribose) levels in nuclei by H2O2 treatment, and the sensitization of H2O2-induced TRPM2 activation were almost completely blocked by poly(ADP-ribose) polymerase inhibitors, suggesting that intracellular Fe(2+)-accumulation enhances H2O2-induced TRPM2 activation by increase of ADP-ribose production through poly(ADP-ribose) polymerase pathway. Similarly, pretreatment with FeSO4 stimulated H2O2-induced TRPM2 activation at 37°C in U937 cells and enhanced H2O2-induced ERK phosphorylation and interleukin-8 (CXCL8) production. Although the addition of H2O2 to cells under conditions of intracellular Fe(2+)-accumulation caused cell death, concentration of H2O2 required for CXCL8 production was lower than that resulting in cell death. These results indicate that intracellular Fe(2+)-accumulation sensitizes TRPM2 channels to H2O2 and subsequently produces CXCL8 at around body temperature. It is possible that sensitization of H2O2-induced TRPM2
Yu, Bang-Wei; Li, Jin-Long; Guo, Bin-Bin; Fan, Hui-Min; Zhao, Wei-Min; Wang, He-Yao
Chlorogenic acid has shown protective effect on cardiomyocytes against oxidative stress-induced damage. Herein, we evaluated nine caffeoylquinic acid analogues (1-9) isolated from the leaves of Gynura nepalensis for their protective effect against H2O2-induced H9c2 cardiomyoblast damage and explored the underlying mechanisms. H9c2 cardiomyoblasts were exposed to H2O2 (0.3 mmol/L) for 3 h, and cell viability was detected with MTT assay. Hoechst 33342 staining was performed to evaluate cell apoptosis. MMPs (mitochondrial membrane potentials) were measured using a JC-1 assay kit, and ROS (reactive oxygen species) generation was measured using CM-H2 DCFDA. The expression levels of relevant proteins were detected using Western blot analysis. Exposure to H2O2 markedly decreased the viability of H9c2 cells and catalase activity, and increased LDH release and intracellular ROS production; accompanied by a loss of MMP and increased apoptotic rate. Among the 9 chlorogenic acid analogues as well as the positive control drug epigallocatechin gallate (EGCG) tested, compound 6 (3,5-dicaffeoylquinic acid ethyl ester) was the most effective in protecting H9c2 cells from H2O2-induced cell death. Pretreatment with compound 6 (1.56-100 μmol/L) dose-dependently alleviated all the H2O2-induced detrimental effects. Moreover, exposure to H2O2 significantly increased the levels of Bax, p53, cleaved caspase-8, and cleaved caspase-9, and decreased the level of Bcl-2, resulting in cell apoptosis. Exposure to H2O2 also significantly increased the phosphorylation of p38, JNK and ERK in the H9c2 cells. Pretreatment with compound 6 (12.5 and 25 μmol/L) dose-dependently inhibited the H2O2-induced increase in the level of cleaved caspase-9 but not of cleaved caspase-8. It also dose-dependently suppressed the H2O2-induced phosphorylation of JNK and ERK but not that of p38. Compound 6 isolated from the leaves of Gynura nepalensis potently protects H9c2 cardiomyoblasts against H2O2-induced
Yu, Jie; Zheng, Jiacheng; Lin, Jiajia; Jin, Linlu; Yu, Rui; Mak, Shinghung; Hu, Shengquan; Sun, Hongya; Wu, Xiang; Zhang, Zaijun; Lee, Mingyuen; Tsim, Wahkeung; Su, Wei; Zhou, Wenhua; Cui, Wei; Han, Yifan; Wang, Qinwen
Oxidative stress-induced neuronal apoptosis plays an important role in many neurodegenerative disorders. In this study, we have shown that indirubin-3-oxime, a derivative of indirubin originally designed for leukemia therapy, could prevent hydrogen peroxide (H2O2)-induced apoptosis in both SH-SY5Y cells and primary cerebellar granule neurons. H2O2 exposure led to the increased activities of glycogen synthase kinase 3β (GSK3β) and extracellular signal-regulated kinase (ERK) in SH-SY5Y cells. Indirubin-3-oxime treatment significantly reversed the altered activity of both the PI3-K/Akt/GSK3β cascade and the ERK pathway induced by H2O2. In addition, both GSK3β and mitogen-activated protein kinase inhibitors significantly prevented H2O2-induced neuronal apoptosis. Moreover, specific inhibitors of the phosphoinositide 3-kinase (PI3-K) abolished the neuroprotective effects of indirubin-3-oxime against H2O2-induced neuronal apoptosis. These results strongly suggest that indirubin-3-oxime prevents H2O2-induced apoptosis via concurrent inhibiting GSK3β and the ERK pathway in SH-SY5Y cells, providing support for the use of indirubin-3-oxime to treat neurodegenerative disorders caused or exacerbated by oxidative stress.
Lu, Shaoyun; Zhuo, Chunliu; Wang, Xianghui; Guo, Zhenfei
Abscisic acid (ABA), H2O2 and nitric oxide (NO) are important signals in gene expression and physiological responses during plant adaptation to environmental stresses. The essential role of NR-derived NO production in ABA and H2O2 induced antioxidant enzymes were studied using transgenic tobacco plants over-expressing Stylosanthes guianensis 9-cis-epoxycartenoid dioxygenase gene (SgNCED1) for elevated ABA level, or over-expressing wheat oxalate oxidase gene (OxO) for elevated H2O2 level in comparison to the wild type. Compared to the wild type, higher levels of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and nitrate reductase (NR) activities and NO production were observed in all transgenic plants. For investigating the relationship of ABA, H2O2, and NR-produced NO in the induction of antioxidant enzyme activities, an inhibitor of ABA biosynthesis, scavengers of H2O2 and NO, and an inhibitor of NR were used in the experiments. The results indicate that H2O2-induced activities of SOD, CAT, and APX depends on NR-derived NO in OxO transgenic plants, while ABA-induced activities depends on H2O2 and NR-derived NO in SgNCED1 transgenic plants. Compared to unaltered nitrate reductase 2 (NIA2), NIA1 transcript was induced in both types of transgenic plants. It is suggested NR-derived NO is essential for ABA- or H2O2-induced antioxidant enzyme activities. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Brand, A; Gil, S; Seger, R; Yavin, E
The present work examines the effect of membrane lipid composition on activation of extracellular signal-regulated protein kinases (ERK) and cell death following oxidative stress. When subjected to 50 microM docosahexaenoic acid (DHA, 22 : 6 n-3), cellular phospholipids of OLN 93 cells, a clonal line of oligodendroglia origin low in DHA, were enriched with this polyunsaturated fatty acid. In the presence of 1 mM N,N-dimethylethanolamine (dEa) a new phospholipid species analog was formed in lieu of phosphatidylcholine. Exposure of DHA-enriched cells to 0.5 mM H2O2, caused sustained activation of ERK up to 24 h. At this time massive apoptotic cell death was demonstrated by ladder and TUNEL techniques. H2O2-induced stress applied to dEa or DHA/dEa co-supplemented cells showed only a transient ERK activation and no cell death after 24 h. Moreover, while ERK was rapidly translocated into the nucleus in DHA-enriched cells, dEa supplements completely blocked ERK nuclear translocation. This study suggests that H2O2-induced apoptotic cell death is associated with prolonged ERK activation and nuclear translocation in DHA-enriched OLN 93 cells, while both phenomena are prevented by dEa supplements. Thus, the membrane lipid composition ultimately modulates ERK activation and translocation and therefore can promote or prevent apoptotic cell death.
Full Text Available Wampee (Clausena lansium fruits (CLS, whose pulp can be used to prepare fruit cups, desserts, jam, or jelly, can be eaten along with the peel. In this study, a PC12 cell model was built to observe the protective effect of CLS against H2O2-induced oxidative stress. We found that pretreatment with CLS increased cell viability and inhibited cytotoxicity, caspase-3 activity and DNA condensation. CLS also attenuated the increase in ROS production and MMP reduction. Moreover, we attempted to determine whether CLS suppressed the expression and phosphorylation of NF-κB. Western blot and immunostaining assay revealed that CLS inhibited H2O2-induced up-regulation of NF-κB p65 and pNF-κB p65. And CLS significantly suppressed the translocation of NF-κB p65 and pNF-κB p65 from cytoplasm to nuclear. Also, seven major compounds including a new flavanoid, luteolin-4'-O-β-d-gluco-pyranoside (3 and six known compounds 1,2, 4–7 were isolated and identified from CLS. Their antioxidative and H2O2-induced PC12 cell apoptosis-reversing activity were determined. These findings suggest that CLS and its major constituents (flavanoids may be potential antioxidant agents and should encourage further research into their use as a functional food for neurodegenerative diseases.
Full Text Available Adipose tissue secretes numerous hormone-like factors, which are known as adipokines. Adipokine receptors have been identified in the central nervous system but the potential role of adipokine signaling in neuroprotection is unclear. The aim of this study is to determine (1 Whether adipokines secreted from cultured adipose tissue of lean humans is protective against oxidative stress-induced neurotoxicity in human SH-SY5Y neuronal cells; and (2 To explore potential signaling pathways involved in these processes. Adipose tissue conditioned media (ATCM from healthy lean subjects completely prevented H2O2 induced neurotoxicity, while this effect is lost after heating ATCM. ATCM activated the phosphorylation of ERK1/2, JNK and Akt at serine 308 in SH-SY5Y cells. PD98059 (25 µM, SP600125 (5 µM and LY29400 (20 µM partially blocked the protective effects of ATCM against H2O2 induced neurotoxicity. Findings demonstrate that heat-sensitive factors secreted from human adipose tissue of lean subjects are protective against H2O2 induced neurotoxicity and ERK1/2, JNK, and PI3K signaling pathways are involved in these processes. In conclusion, this study demonstrates preliminary but encouraging data to further support that adipose tissue secreted factors from lean human subjects might possess neuroprotective properties and unravel the specific roles of ERK1/2, JNK and PI3K in these processes.
Singh, Ajeet Kumar; Vinayak, Manjula
Concomitant generation of reactive oxygen species during tissue inflammation has been recognised as a major factor for the development and the maintenance of hyperalgesia, out of which H2O2 is the major player. However, molecular mechanism of H2O2 induced hyperalgesia is still obscure. The aim of present study is to analyse the mechanism of H2O2-induced hyperalgesia in rats. Intraplantar injection of H2O2 (5, 10 and 20 µmoles/paw) induced a significant thermal hyperalgesia in the hind paw, confirmed by increased c-Fos activity in dorsal horn of spinal cord. Onset of hyperalgesia was prior to development of oxidative stress and inflammation. Rapid increase in phosphorylation of extracellular signal regulated kinase (ERK) was observed in neurons of dorsal root ganglia after 20 min of H2O2 (10 µmoles/paw) administration, which gradually returned towards normal level within 24 h, following the pattern of thermal hyperalgesia. The expression of TNFR1 followed the same pattern and colocalised with pERK. ERK phosphorylation was observed in NF-200-positive and -negative neurons, indicating the involvement of ERK in C-fibres as well as in A-fibres. Intrathecal preadministration of Src family kinases (SFKs) inhibitor (PP1) and MEK inhibitor (PD98059) prevented H2O2 induced augmentation of ERK phosphorylation and thermal hyperalgesia. Pretreatment of protein tyrosine phosphatases (PTPs) inhibitor (sodium orthovanadate) also diminished hyperalgesia, although it further increased ERK phosphorylation. Combination of orthovanadate with PP1 or PD98059 did not exhibit synergistic antihyperalgesic effect. The results demonstrate SFKs-mediated ERK activation and increased TNFR1 expression in nociceptive neurons during H2O2 induced hyperalgesia. However, the role of PTPs in hyperalgesic behaviour needs further molecular analysis.
Sai Wang Seto
Full Text Available Sailuotong (SLT is a standardised three-herb formulation consisting of Panax ginseng, Ginkgo biloba, and Crocus sativus designed for the management of vascular dementia. While the latest clinical trials have demonstrated beneficial effects of SLT in vascular dementia, the underlying cellular mechanisms have not been fully explored. The aim of this study was to assess the ability and mechanisms of SLT to act against hydrogen peroxide (H2O2-induced oxidative damage in cultured human vascular endothelial cells (EAhy926. SLT (1–50 µg/mL significantly suppressed the H2O2-induced cell death and abolished the H2O2-induced reactive oxygen species (ROS generation in a concentration-dependent manner. Similarly, H2O2 (0.5 mM; 24 h caused a ~2-fold increase in lactate dehydrogenase (LDH release from the EA.hy926 cells which were significantly suppressed by SLT (1–50 µg/mL in a concentration-dependent manner. Incubation of SLT (50 µg/mL increased superoxide dismutase (SOD activity and suppressed the H2O2-enhanced Bax/Bcl-2 ratio and cleaved caspase-3 expression. In conclusion, our results suggest that SLT protects EA.hy916 cells against H2O2-mediated injury via direct reduction of intracellular ROS generation and an increase in SOD activity. These protective effects are closely associated with the inhibition of the apoptotic death cascade via the suppression of caspase-3 activation and reduction of Bax/Bcl-2 ratio, thereby indicating a potential mechanism of action for the clinical effects observed.
Ai, Hou-Xi; Wang, Wen; Sun, Fang-Lin; Huang, Wen-Ting; An, Yi; Li, Lin
To investigate the effects of morroniside on H2O2-induced apoptosis in nerve cells. Human neuroblastoma cell line SH-SY5Y cells were pre-incubaed with morroniside (1, 10, and 100 micromol x L(-1)) for 24 h prior to exposure to H2O2 (500 micromol x L(-1)) for 18 h. The activity of reactive SOD was measured by a biochemical assay. The expression of caspase-3, caspase-9, Bcl-2 and Bax was determined by Wastern blotting method. Pretreatment of the cells with morroniside (10 and 100 micromol x L(-1)) increasd SOD activity by 14% (P<0.01) and 11% (P<0.05) in comparison with cells exposed only to H2O2. Morroniside (1, 10, 100 micromol x L(-1)) lowered caspase-3 level by 31% (P<0.01), 103% (P<0.001) and 95% (P<0.001), decreased caspase-9 content by 71% (P<0.001), 132% (P<0.001) and 37% (P<0.05), and increasd Bcl-1 level by 88% (P<0.01), 121% (P<0.001) and 60% (P<0.01) respectively but no significant change occurred in Bax level in comparison with cells exposed only to H2O2. Morroniside has neuroprotection effect against H2O2-induced oxidation injury in nerve cell.
Li, Ran; Yin, Fei; Guo, Ying-Ying; Zhao, Kun-Chi; Ruan, Qing; Qi, Ying-Mei
Spinal cord injury (SCI) is a devastating and common neurological disorder which causes local oxidative damage. The study aimed to investigate the underlying role of ANRIL in H2O2-induced cell injury of rat PC-12 cells. Cell injury was evaluated on the basis of cell viability, migration, invasion and apoptosis. The effect of ANRIL on H2O2-induced cell injury was estimated after cell transfection. Then, the interaction between ANRIL and miR-125a was explored by qRT-PCR and estimation of cell injury. Predicted by TargetScan, the possible target gene of miR-125a was verified. After that, the effects of aberrantly expressed target gene on cell viability, migration, invasion and apoptosis as well as phosphorylation of key kinases involved in JAK/STAT and ERK/MAPK pathways were evaluated. Results revealed that H2O2-induced PC-12 cell injury could be aggravated by ANRIL suppression. ANRIL appeared to act as a sponge of miR-125a, and ANRIL suppression promoted H2O2-induced cell injury by up-regulation of miR-125a. MCL-1 was a target of miR-125a, and MCL-1 was negatively correlated with miR-125a. Subsequent experiments showed the effect of MCL-1 silence on H2O2-induced PC-12 cell injury was the same as ANIRL suppression. MCL-1 attenuated H2O2-induced PC-12 cell injury by activating JAK/STAT and ERK/MAPK pathways. These findings suggested that knockdown of ANRIL aggravates H2O2-induced injury in PC-12 cells by targeting miR-125a. This might provide novel insights in the role of ANRIL in pathogenesis of oxidative damage during SCI. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Full Text Available In this work, we designed and synthesized a series of amide derivatives (1–13, benzoxazine derivatives (16–28 and amino derivatives (29–30 from xyloketal B. All 28 new derivatives and seven known compounds (14, 15, 31–35 were evaluated for their protection against H2O2-induced HUVEC injury. 23 and 24 exhibited more potential protective activities than other derivatives; and the EC50 values of them and the leading compound 31 (xyloketal B were 5.10, 3.59 and 15.97 μM, respectively. Meanwhile, a comparative molecular similarity indices analysis (CoMSIA was constructed to explain the structural activity relationship of these xyloketal derivatives. This 3D QSAR model from CoMSIA suggested that the derived model exhibited good predictive ability in the external test-set validation. Derivative 24 fit well with the COMSIA map, therefore it possessed the highest activity of all compounds. Compounds 23, 24 and 31 (xyloketal B were further to examine in the JC-1 mitochondrial membrane potential (MMP assay of HUVECs using flow cytometry (FCM. The result indicated that 23 and 24 significantly inhibited H2O2-induced decrease of the cell mitochondrial membrane potential (ΔΨm at 25 μM. Collectively, the protective effects of xyloketals on H2O2-induced endothelial cells may be generated from oxidation action by restraining ROS and reducing the MMP.
Seo, Young Lan; Heo, Shinhee; Jang, Kyung Lib
Infection with hepatitis C virus (HCV) is characterized by systemic oxidative stress that is caused by either viral core protein or chronic inflammation. It is well recognized that reactive oxygen species (ROS) such as H2O2 can induce apoptotic cell death and can therefore function as anti-tumorigenic species. However, the detailed mechanisms by which ROS induce apoptotic cell death and HCV copes with the oxidative conditions are largely unknown. In the present study, we found that H2O2 induced apoptotic cell death in p53-positive human hepatocytes, but not in p53-negative human hepatocytes. For this effect, H2O2 upregulated levels of p14, increased ubiquitin-dependent degradation of mouse double minute 2 (MDM2), and reduced the interaction between MDM2 and p53 to prevent p53 degradation, resulting in accumulation of p53 and subsequent activation of p53-dependent apoptotic pathways. Interestingly, HCV core repressed p14 expression via promoter hypermethylation to abolish the potential of H2O2 to activate the p14-MDM2-p53 pathway. As a consequence, HCV core-expressing cells could overcome p53-mediated apoptosis provoked by H2O2. Taken together, HCV core could contribute to hepatocellular carcinoma formation by removing deleterious roles of ROS inducing cell death. © 2015 The Authors.
Ji, Guang; Zhang, Weiwei; Quan, Moyuan; Chen, Yang; Qu, Hui; Hu, Zhiping
This study aimed to investigate the effects of H2O2-induced oxidative stress on cell viability and survival, as well as changes in the distribution of Golgi apparatus and in the level of Golgi reassembly and stacking protein 65 (GRASP65). Cell viability of cultured N2a cells treated with H2O2 was measured by the MTT assay. Apoptosis was measured by flow cytometry analyses. Cells labeled by indirect immunofluorescence were observed under confocal microscope to detect any Golgi morphological alterations; electron microscopy of Golgi apparatus was also done. Expression of GRASP65 and phospho-GRASP65 was examined by immunoblotting. H2O2 treatment reduced the cell viability and raised the cell mortality of N2a cells in a time-dependent manner. Notable changes were only observed in the distribution and morphology of Golgi apparatus at 6 h after H2O2 treatment. The expression of GRASP65 showed no significant changes at different time points; the phosphorylated GRASP65 level was significantly increased after H2O2 treatment, peaked at 3 h, and finally dropped at 6 h. Taken together, GRASP65 phosphorylation may have a critical role in inducing cell death at the early stage after H2O2 treatment, while its role in H2O2-induced Golgi morphological changes may be complex.
Kwang Min Lee
Full Text Available Oxidative stress plays a significant role in the etiology of a variety of neurodegenerative diseases. In this study, we found that Melandrii Herba extract (ME attenuated oxidative-induced damage in cells. Mechanistically, ME exhibited protection from H2O2-induced neurotoxicity via caspase-3 inactivation, Bcl-2 downregulation, Bax upregulation, and MAPK activation (ERK 1/2, JNK 1/2, and p38 MAPK in vitro. Moreover, our in vivo data showed that ME was able to attenuate scopolamine-induced cognitive impairment. These results provide in vitro and in vivo evidence that ME exhibits neuroprotective properties against oxidative stress, which suggests that ME is worthy of further investigation as a complementary, or even as an alternative, product for preventing and treating neurodegenerative disorders.
Park, Min-Ja; Bae, Young-Seuk
The present study assessed the effects of an aqueous extract of Acanthopanax koreanum root (AE) and of AE following fermentation by lactic acid bacteria (Lactobacillus plantarum and Bifidobacterium bifidum) (AEF) on human skin fibroblast HS68 cells exposed to ultraviolet B (UVB) irradiation and oxidative stress. AEF effectively antagonized the senescence-associated β-galactosidase staining and upregulation of p53 and p21(Cip1/WAF1) induced by UVB or H2O2 treatment in HS68 cells. It also exhibited excellent antioxidant activities in radical scavenging assays and reduced the intracellular level of reactive oxygen species induced by UVB or H2O2 treatment. The antioxidant and antisenescent activities of AEF were greater than those of nonfermented A. koreanum extract. AEF significantly repressed the UVB- or H2O2-induced activities of matrix metalloproteinase (MMP)-1 and -3, overexpression of MMP-1, and nuclear factor κB (NF-κB) activation. This repression of NF-κB activation and MMP-1 overexpression was attenuated by a mitogen-activated protein kinase activator, suggesting that this AEF activity was dependent on this signaling pathway. Taken together, these data indicated that AEF-mediated antioxidant and anti-photoaging activities may produce anti-wrinkle effects on human skin.
Kim, Young-Jun; Seo, Sang Gwon; Choi, Keunhwa; Kim, Jong Eun; Kang, Heerim; Chung, Min-Yu; Lee, Ki Won; Lee, Hyong Joo
Cellular oxidative damage mediated by reactive oxygen species has been reported to inhibit gap-junctional intercellular communication (GJIC). In turn, the inhibition of GJIC can be attenuated by functional food compounds with antioxidant properties. In this study, we compared the protective effects of onion peel extract (OPE) and onion flesh extract (OFE) on oxidative stress-mediated GJIC inhibition, and investigated the mechanisms of action responsible. OPE restored H2 O2 -induced GJIC inhibition to a higher degree than OFE in WB-F344 rat liver epithelial cells. OPE was found to inhibit H2 O2 -induced phosphorylation of ERK1/2 and Cx43. A radical scavenging assay demonstrated superiority of OPE over OFE, suggesting that the observed effects might be mediated via an antioxidant mechanism. Quercetin is the major compound that is likely to be responsible for the protective effect against H2 O2 -mediated GJIC inhibition. This study suggests that OPE, a material often discarded, may be of value for the future development of functional food products. This study demonstrates that onion peel extract (OPE) exhibits a protective effect against the inhibition of gap-junctional intercellular communication (GJIC) mediated by H2 O2 , which is likely to occur via its antioxidant activity. OPE contains significant concentrations of bioactive phenolic compounds. Reductions in oxidative stress can lead to recovery of GJIC, which has been reported to be implicated in the prevention and treatment of cancers. These findings suggest that onion peel, a common waste product, could be used as potential resources for functional food development. Onion peel could be processed into a quercetin-rich powder or a pill for the prevention of cancer and other oxidative stress-related diseases. © 2014 Institute of Food Technologists®
Zhou, Xueping; Yuan, Dong; Wang, Mingxia
Although elevated levels of H2O2 have been implicated to play important roles in the pathogenesis of various cardiovascular diseases, the underlying mechanisms remain unclear. This study aims to examine the effect of H2O2 on endothelial nitric oxide (NO) production in intact venules, and elucidate the role and mechanisms of NO in H2O2-induced increases in microvessel permeability. Experiments were conducted on individually perfused rat mesenteric venules. Microvessel permeability was determined by measuring hydraulic conductivity (Lp), and endothelial [Ca2+]i was measured on fura-2-loaded vessels. Perfusion of H2O2 (10 μM) caused a delayed and progressively increased endothelial [Ca2+]i and Lp, a pattern different from inflammatory mediator-induced immediate and transient response. Under the same experimental conditions, measuring endothelial NO via DAF-2 and the spatial detection of cell apoptosis by fluorescent markers revealed that H2O2 induced two phases of NO production followed by caspase activation, intracellular Ca2+ accumulation, and vascular cell apoptosis. The initial NO production was correlated with increased endothelial NO synthase (eNOS) Ser1177 phosphorylation in the absence of elevated endothelial [Ca2+]i, whereas the second phase of NO depended on increased [Ca2+]i and was associated with Thr495 dephosphorylation without increased Ser1177 phosphorylation. Inhibition of NOS prevented H2O2-induced caspase activation, cell apoptosis, and increases in endothelial [Ca2+]i and Lp. Our results indicate that H2O2 at micromolar concentration is able to induce a large magnitude of NO in intact venules, causing caspase activation-mediated endothelial Ca2+ accumulation, cell apoptosis, and increases in permeability. The mechanisms revealed from intact microvessels may contribute to the pathogenesis of oxidant-related cardiovascular diseases. PMID:23086988
Samuni, Amram; Maimon, Eric; Goldstein, Sara
Horseradish peroxidase (HRP) catalyzes H2O2 dismutation while undergoing heme inactivation. The mechanism underlying this process has not been fully elucidated. The effects of nitroxides, which protect metmyoglobin and methemoglobin against H2O2-induced inactivation, have been investigated. HRP reaction with H2O2 was studied by following H2O2 depletion, O2 evolution and heme spectral changes. Nitroxide concentration was followed by EPR spectroscopy, and its reactions with the oxidized heme species were studied using stopped-flow. Nitroxide protects HRP against H2O2-induced inactivation. The rate of H2O2 dismutation in the presence of nitroxide obeys zero-order kinetics and increases as [nitroxide] increases. Nitroxide acts catalytically since its oxidized form is readily reduced to the nitroxide mainly by H2O2. The nitroxide efficacy follows the order 2,2,6,6-tetramethyl-piperidine-N-oxyl (TPO)>4-OH-TPO>3-carbamoyl proxyl>4-oxo-TPO, which correlates with the order of the rate constants of nitroxide reactions with compounds I, II, and III. Nitroxide catalytically protects HRP against inactivation induced by H2O2 while modulating its catalase-like activity. The protective role of nitroxide at μM concentrations is attributed to its efficient oxidation by P940, which is the precursor of the inactivated form P670. Modeling the dismutation kinetics in the presence of nitroxide adequately fits the experimental data. In the absence of nitroxide the simulation fits the observed kinetics only if it does not include the formation of a Michaelis-Menten complex. Nitroxides catalytically protect heme proteins against inactivation induced by H2O2 revealing an additional role played by nitroxide antioxidants in vivo. Copyright © 2017 Elsevier B.V. All rights reserved.
Clementi, Maria Elisabetta; Pani, Giovambattista; Sampaolese, Beatrice; Tringali, Giuseppe
Oxidative stress has long been linked to neuronal cell death in many neurodegenerative diseases. Antioxidant conventional supplements are poorly effective in preventing neuronal damage caused by oxidative stress due to their inability to cross the blood brain barrier. Hence the use of molecules extracted from plants and fruits such as phenolics, flavonoids, and terpenoids compounds constitute a new wave of antioxidant therapies to defend against free radicals. In this study we examined the effects of punicalagin, a ellagitannin isolated from the pomegranate juice, on a rat adrenal pheochromocytoma cell line, treated with hydrogen peroxide, evaluating the viability, oxidation potential, mitochondrial function, and eventual apoptosis. This study was performed on PC12 cells pretreated with punicalagin (0.5, 1, 5, 10 e 20 µM) 24 hours before of the damage by hydrogen peroxide (H 2 O 2 ). H 2 O 2 concentration (300 µM) used in our study was determined by preliminary experiments of time course. The cell viability and ROS production were evaluated by MTS assay and cytofluorometry assays, respectively. Subsequently, the number of apoptotic-positive cells and mitochondrial transmembrane potential, were measured by flow cytometry, in the same experimental paradigm. Finally, the expression of Bax and enzymatic activity of Caspase 3, some of the principle actors of programmed cell death, were investigated by semiquantitative PCR and utilizing a colorimetric assay kit, respectively. We found that pretreatment with punicalagin protected the cells from H 2 O 2 -induced damage. In particular, the protective effect seemed to be correlated with a control both in radical oxygen species production and in mitochondrial functions. In fact the cells treated with H 2 O 2 showed an altered mitochondrial membrane integrity while the pretreatment with punicalagin retained both the cellular viability and the mitochondrial membrane potential similar to the control. Furthermore, the
Full Text Available Trehalose is a non-reducing disaccharide and can be accumulated in response to heat or oxidative stresses in Candida albicans. Here we showed that a C. albicans tps1Δ mutant, which is deficient in trehalose synthesis, exhibited increased apoptosis rate upon H(2O(2 treatment together with an increase of intracellular Ca(2+ level and caspase activity. When the intracellular Ca(2+ level was stimulated by adding CaCl(2 or A23187, both the apoptosis rate and caspase activity were increased. In contrast, the presence of two calcium chelators, EGTA and BAPTA, could attenuate these effects. Moreover, we investigated the role of Ca(2+ pathway in C. albicans apoptosis and found that both calcineurin and the calcineurin-dependent transcription factor, Crz1p, mutants showed decreased apoptosis and caspase activity upon H(2O(2 treatment compared to the wild-type cells. Expression of CaMCA1, the only gene found encoding a C. albicans metacaspase, in calcineurin-deleted or Crz1p-deleted cells restored the cell sensitivity to H(2O(2. Our results suggest that Ca(2+ and its downstream calcineurin/Crz1p/CaMCA1 pathway are involved in H(2O(2-induced C. albicans apoptosis. Inhibition of this pathway might be the mechanism for the protective role of trehalose in C. albicans.
Choi, Doo Jin; Cho, Sarang; Seo, Jeong Yeon; Lee, Hyang Burm; Park, Yong Il
Numerous studies have suggested that neuronal cells are protected against oxidative stress-induced cell damage by antioxidants, such as polyphenolic compounds. Phellinus linteus (PL) has traditionally been used to treat various symptoms in East Asian countries. In the present study, we prepared an ethyl acetate extract from the fruiting bodies of PL (PLEA) using hot water extraction, ethanol precipitation, and ethyl acetate extraction. The PLEA contained polyphenols as its major chemical component, and thus, we predicted that it may exhibit antioxidant and neuroprotective effects against oxidative stress. The results showed that the pretreatment of human brain neuroblastoma SK-N-MC cells with the PLEA (0.1-5 μg/mL) significantly and dose-dependently reduced the cytotoxicity of H2O2 and the intracellular ROS levels and enhanced the expression of HO-1 (heme oxygenase-1) and antioxidant enzymes, such as CAT (catalase), GPx-1 (glutathione peroxidase-1), and SOD-1 and -2 (superoxide dismutase-1 and -2). The PLEA also directly scavenged free radicals. PLEA pretreatment also significantly attenuated DNA fragmentation and suppressed the mRNA expression and activation of mitogen-activated protein kinases extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 kinase, which are induced by oxidative stress and lead to cell death. PLEA pretreatment inhibited the activation of the apoptosis-related proteins caspase-3 and poly (ADP-ribose) polymerase. These results demonstrate that the PLEA has neuroprotective effects against oxidative stress (H2O2)-induced neuronal cell death via its antioxidant and anti-apoptotic properties. PLEA should be investigated in an in vivo model on its potential to prevent or ameliorate neurodegenerative disease. Copyright © 2016 Elsevier Inc. All rights reserved.
Wang, Yongyi; Men, Min; Xie, Bo; Shan, Jianggui; Wang, Chengxi; Liu, Jidong; Zheng, Hui; Yang, Wengang; Xue, Song; Guo, Changfa
Reactive oxygenation species (ROS) generated from reperfusion results in cardiac injury through apoptosis and inflammation, while PKR has the ability to promote apoptosis and inflammation. The aim of the study was to investigate whether PKR is involved in hydrogen peroxide (H2O2) induced neonatal cardiac myocytes (NCM) injury. In our study, NCM, when exposed to H2O2, resulted in persistent activation of PKR due to NCM endogenous RNA. Inhibition of PKR by 2-aminopurine (2-AP) or siRNA protected against H2O2 induced apoptosis and injury. To elucidate the mechanism, we revealed that inhibition of PKR alleviated H2O2 induced apoptosis companied by decreased caspase3/7 activity, BAX and caspase-3 expression. We also revealed that inhibition of PKR suppressed H2O2 induced NFκB pathway and NLRP3 activation. Finally, we found ADAR1 mRNA and protein expression were both induced after H2O2 treatment through STAT-2 dependent pathway. By gain and loss of ADAR1 expression, we confirmed ADAR1 modulated PKR activity. Therefore, we concluded inhibition of PKR protected against H2O2-induced injury by attenuating apoptosis and inflammation. A self-preservation mechanism existed in NCM that ADAR1 expression is induced by H2O2 to limit PKR activation simultaneously. These findings identify a novel role for PKR/ADAR1 in myocardial reperfusion injury.
Zhou, Yue; Dong, Ying; Xu, Qing-Gang; Zhu, Shu-Yun; Tian, Shi-Lei; Huo, Jing-jing; Hao, Ting-Ting; Zhu, Bei-Wei
Mussel bioactive peptides have been viewed as mediators to maximize the high quality of life. In this study, the anti-aging activities of mussel oligopeptides were evaluated using H2O2-induced prematurely senescent MRC-5 fibroblasts. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry displayed that exposure to H2O2 led to the loss of cell viability and cell cycle arrest. In addition, H2O2 caused the elevation of senescence-associated-β-galactosidase (SA-β-gal) activity and formation of senescence-associated heterochromatin foci (SAHF). It was found that pretreatment with mussel oligopeptides could significantly attenuate these properties associated with cellular senescence. Mussel oligopeptides also led to the increase of glutathione (GSH) level and mitochondrial transmembrane potential (Δψm) recovery. In addition, mussel oligopeptides resulted in an improvement in transcriptional activity of peroxiredoxin 1 (Prx1), nicotinamide phosphoribosyltransferase (NAMPT) and sirtuin 1 (SIRT1). This study revealed that mussel oligopeptides could protect against cellular senescence induced by H2O2, and the effects were closely associated with redox cycle modulating and potentiating the SIRT1 pathway. These findings provide new insights into the beneficial role of mussel bioactive peptides on retarding senescence process. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.
Yamamoto, Shinichiro; Toda, Takahiro; Yonezawa, Ryo; Negoro, Takaharu; Shimizu, Shunichi
TRPM2 is a Ca2+-permeable channel that is activated by H2O2. TRPM2-mediated Ca2+ signaling has been implicated in the aggravation of inflammatory diseases. Therefore, the development of TRPM2 inhibitors to prevent the aggravation of these diseases is expected. We recently reported that some Tyrphostin AG-related compounds inhibited the H2O2-induced activation of TRPM2 by scavenging the intracellular hydroxyl radical. In the present study, we examined the effects of AG-related compounds on H2O2-induced cellular responses in human monocytic U937 cells, which functionally express TRPM2. The effects of AG-related compounds on H2O2-induced changes in intracellular Ca2+ concentrations, extracellular signal-regulated kinase (ERK) activation, and CXCL8 secretion were assessed using U937 cells. Ca2+ influxes via TRPM2 in response to H2O2 were blocked by AG-related compounds. AG-related compounds also inhibited the H2O2-induced activation of ERK, and subsequent secretion of CXCL8 mediated by TRPM2-dependent and -independent mechanisms. Our results show that AG-related compounds inhibit H2O2-induced CXCL8 secretion following ERK activation, which is mediated by TRPM2-dependent and -independent mechanisms in U937 cells. We previously reported that AG-related compounds blocked H2O2-induced TRPM2 activation by scavenging the hydroxyl radical. The inhibitory effects of AG-related compounds on TRPM2-independent responses may be due to scavenging of the hydroxyl radical. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.
Ostrowski, Tim D.; Hasser, Eileen M.; Heesch, Cheryl M.; Kline, David D.
Hydrogen peroxide (H2O2) is a stable reactive oxygen species and potent neuromodulator of cellular and synaptic activity. Centrally, endogenous H2O2 is elevated during bouts of hypoxia-reoxygenation, a variety of disease states, and aging. The nucleus tractus solitarii (nTS) is the central termination site of visceral afferents for homeostatic reflexes and contributes to reflex alterations during these conditions. We determined the extent to which H2O2 modulates synaptic and membrane properties in nTS neurons in rat brainstem slices. Stimulation of the tractus solitarii (which contains the sensory afferent fibers) evoked synaptic currents that were not altered by 10 – 500 μM H2O2. However, 500 μM H2O2 modulated several intrinsic membrane properties of nTS neurons, including a decrease in input resistance, hyperpolarization of resting membrane potential (RMP) and action potential (AP) threshold (THR), and an initial reduction in AP discharge to depolarizing current. H2O2 increased conductance of barium-sensitive potassium currents, and block of these currents ablated H2O2-induced changes in RMP, input resistance and AP discharge. Following washout of H2O2 AP discharge was enhanced due to depolarization of RMP and a partially maintained hyperpolarization of THR. Hyperexcitability persisted with repeated H2O2 exposure. H2O2 effects on RMP and THR were ablated by intracellular administration of the antioxidant catalase, which was immunohistochemically identified in neurons throughout the nTS. Thus, H2O2 initially reduces excitability of nTS neurons that is followed by sustained hyperexcitability, which may play a profound role in cardiorespiratory reflexes. PMID:24397952
Full Text Available We have previously reported that Ginsenoside Rb1 may effectively prevent HUVECs from senescence, however, the detailed mechanism has not demonstrated up to now. Recent studies have shown that sirtuin-1 (Sirt1 plays an important role in the development of endothelial senescence. The purpose of this study was to explore whether Sirt1 is involved in the action of Ginsenoside Rb1 regarding protection against H2O2-induced HUVEC Senescence.Senescence induced by hydrogen peroxide (H2O2 in human umbilical vein endothelial cells (HUVECs was examined by analyzing plasminogen activator inhibitor-1 (PAI-1 expression, cell morphology, and senescence-associated beta-galactosidase (SA-β-gal activity. The results revealed that 42% of control-treated HUVECs were SA-β-gal positive after treatment by 60 µmol/L H2O2, however, this particular effect of H2O2 was decreased more than 2-fold (19% in the HUVECs when pretreated with Rb1 (20 µmol/L for 30 min. Additionally, Rb1 decreased eNOS acetylation, as well as promoted more NO production that was accompanied by an increase in Sirt1 expression. Furthermore, upon knocking down Sirt1, the effect of Rb1 on HUVEC senescence was blunted.The present study indicated that Ginsenoside Rb1 acts through stimulating Sirt1 in order to protect against endothelial senescence and dysfunction. As such, Sirt1 appears to be of particular importance in maintaining endothelial functions and delaying vascular aging.
Veskamide, enferamide, becatamide, and oretamide are phenolic amides whose analogues are found in plants. In this study, the four amides were prepared by chemical synthesis and their protective effects on H(2)O(2)-induced apoptosis in PC-12 cells were investigated. The syntheses were relatively si...
The genotoxicity of reactive oxygen species (ROS) is well established. The underlying mechanism involves oxidation of DNA by ROS. However, we have recently shown that hydrogen peroxide (H2O2), the major mediator of oxidative stress, can also cause genomic damage indirectly. Thus, H2O2 at pathologically relevant ...
Pomari, Elena; Stefanon, Bruno; Colitti, Monica
Background Arctium lappa (AL), Camellia sinensis (CS), Echinacea angustifolia, Eleutherococcus senticosus, Panax ginseng (PG), and Vaccinium myrtillus (VM) are plants traditionally used in many herbal formulations for the treatment of various conditions. Although they are well known and already studied for their anti-inflammatory properties, their effects on H2O2-stimulated macrophages are a novel area of study. Materials and methods Cell viability was tested after treatment with increasing doses of H2O2 and/or plant extracts at different times of incubation to identify the optimal experimental conditions. The messenger (m)RNA expression of TNFα, COX2, IL1β, NFκB1, NFκB2, NOS2, NFE2L2, and PPARγ was analyzed in macrophages under H2O2 stimulation. The same genes were also quantified after plant extract treatment on cells pre-stimulated with H2O2. Results A noncytotoxic dose (200 μM) of H2O2 induced active mRNA expression of COX2, IL1β, NFE2L2, NFκB1, NFκB2, NOS2, and TNFα, while PPARγ was depressed. The expression of all genes tested was significantly (P<0.001) regulated by plant extracts after pre-stimulation with H2O2. COX2 was downregulated by AL, PG, and VM. All extracts depressed IL1β expression, but upregulated NFE2L2. NFκB1, NFκB2, and TNFα were downregulated by AL, CS, PG, and VM. NOS2 was inhibited by CS, PG, and VM. PPARγ was decreased only after treatment with E. angustifolia and E. senticosus. Conclusion The results of the present study indicate that the stimulation of H2O2 on RAW267.4 cells induced the transcription of proinflammatory mediators, showing that this could be an applicable system by which to activate macrophages. Plant extracts from AL, CS, PG, and VM possess in vitro anti-inflammatory activity on H2O2-stimulated macrophages by modulating key inflammation mediators. Further in vitro and in vivo investigation into molecular mechanisms modulated by herbal extracts should be undertaken to shed light on the development of novel
Full Text Available Elena Pomari, Bruno Stefanon, Monica Colitti Department of Agricultural and Environmental Sciences, University of Udine, Udine, Italy Background: Arctium lappa (AL, Camellia sinensis (CS, Echinacea angustifolia, Eleutherococcus senticosus, Panax ginseng (PG, and Vaccinium myrtillus (VM are plants traditionally used in many herbal formulations for the treatment of various conditions. Although they are well known and already studied for their anti-inflammatory properties, their effects on H2O2-stimulated macrophages are a novel area of study. Materials and methods: Cell viability was tested after treatment with increasing doses of H2O2 and/or plant extracts at different times of incubation to identify the optimal experimental conditions. The messenger (mRNA expression of TNFα, COX2, IL1β, NFκB1, NFκB2, NOS2, NFE2L2, and PPARγ was analyzed in macrophages under H2O2 stimulation. The same genes were also quantified after plant extract treatment on cells pre-stimulated with H2O2. Results: A noncytotoxic dose (200 µM of H2O2 induced active mRNA expression of COX2, IL1β, NFE2L2, NFκB1, NFκB2, NOS2, and TNFα, while PPARγ was depressed. The expression of all genes tested was significantly (P<0.001 regulated by plant extracts after pre-stimulation with H2O2. COX2 was downregulated by AL, PG, and VM. All extracts depressed IL1β expression, but upregulated NFE2L2. NFκB1, NFκB2, and TNFα were downregulated by AL, CS, PG, and VM. NOS2 was inhibited by CS, PG, and VM. PPARγ was decreased only after treatment with E. angustifolia and E. senticosus. Conclusion: The results of the present study indicate that the stimulation of H2O2 on RAW267.4 cells induced the transcription of proinflammatory mediators, showing that this could be an applicable system by which to activate macrophages. Plant extracts from AL, CS, PG, and VM possess in vitro anti-inflammatory activity on H2O2-stimulated macrophages by modulating key inflammation mediators. Further in
Rothbart, Sabine; Ember, Erika; van Eldik, Rudi
The kinetics of the hydrogen peroxide induced oxidative degradation of the azo dye Orange II in aqueous carbonate buffered solution were studied for the oxo-bridged [Mn(2)(III/IV)(mu-O)(2)(bpy)(4)](ClO(4))(3) complex and its mononuclear analogue [Mn(II)(bpy)(2)Cl(2)] as catalysts to reveal the underlying reaction mechanism and reactive intermediates participating in the catalytic cycle. Both catalysts show identical oxidative reactivity when used at equimolar manganese concentration. If a simple Mn(II) salt and a 1 : 2 concentration of bipyridine are added to the substrate and oxidant containing reaction mixture, the same oxidative reactivity as found for both readily prepared catalysts was observed for several investigated substrates. This demonstrates the in situ accessibility of a reactive intermediate and its precursor complex. The crucial role of bicarbonate as co-catalyst was studied. The distinct dependence of the observed rate constant for the oxidation reaction on the total carbonate concentration can be accounted for in terms of in situ generation of peroxycarbonate. EPR and rapid scan UV/Vis measurements of the reaction of hydrogen peroxide in carbonate buffered solution with [Mn(2)(III/IV)(mu-O)(2)(bpy)(4)](ClO(4))(3) and [Mn(II)(bpy)(2)Cl(2)], revealed for both catalysts the presence of monomeric Mn(II) and Mn(IV)-oxo species as the main intermediates. The proposed reaction mechanism involves two-electron oxidation of a mononuclear Mn(II) precursor complex to a high-valent Mn(IV)=O intermediate as catalytically active species. Differences in the activity of in situ prepared catalyst precursors of different metal to ligand ratios are reported. The 1 : 2 complex was found to be the catalytically more active precursor for the oxidation of the selected substrates, whereas the 1 : 3 complex rather catalyzed the disproportion of hydrogen peroxide.
Shimizu, Yuri; Miyakura, Reiko; Otsuka, Yuzuru
Apoptosis is characterized by distinct morphological and biochemical changes that occur upon activation of a family of serine proteases known as caspases. Reactive oxygen species (ROS) induce apoptosis in many cell systems. Nuclear receptor subfamily 4, group A, member 1 (NR4A1) has been shown to induce apoptosis in a number of cell lineages, but can also paradoxically act as a death inhibitory factor. In the current study, we focused on the potential role of NR4A1 in hydrogen peroxide (H2O2)-induced apoptosis of normal human umbilical cord fibroblast (HUC-F2) cells. Growth of HUC-F2 cells treated with H2O2 was measured by MTT assay. Analysis of gene expression was performed with a STEP ONE PLUS Real Time PCR system. Inactivation of NR4A1 was treated with siRNA. Apoptosis was measured by Beckman Coulter flow cytometer after inhibition of NR4A1 with siRNA and H2O2 treatment. Caspase -3, -8 and -9 was measured by caspase assay kit. H2O2 treatment led to enhanced NR4A1 expression. Moreover inhibition of NR4A1 with specific siRNA in HUC-F2 cells triggered an increase in apoptosis and caspase-8 and -3 activities following the addition of H2O2. Our results collectively suggest that NR4A1 is a regulator that inhibits extrinsic apoptosis in HUC-F2 cells during oxidative stress through reduction of caspase-8 and -3 activities.
Park, Woo Hyun
Oxidative stress induces apoptosis in endothelial cells (ECs). Reactive oxygen species (ROS) promote cell death by regulating the activity of various mitogen-activated protein kinases (MAPKs) in ECs. The present study investigated the effects of MAPK inhibitors on cell survival and glutathione (GSH) levels upon H2O2 treatment in calf pulmonary artery ECs (CPAECs). H2O2 treatment inhibited the growth and induced the death of CPAECs, as well as causing GSH depletion and the loss of mitochondrial membrane potential (MMP). While treatment with the MEK or JNK inhibitor impaired the growth of H2O2-treated CPAECs, treatment with the p38 inhibitor attenuated this inhibition of growth. Additionally, JNK inhibitor treatment increased the proportion of sub-G1 phase cells in H2O2-treated CPAECs and further decreased the MMP. However, treatment with a p38 inhibitor reversed the effects of H2O2 treatment on cell growth and the MMP. Similarly, JNK inhibitor treatment further increased, whereas p38 inhibitor treatment decreased, the proportion of GSH-depleted cells in H2O2-treated CPAECs. Each of the MAPK inhibitors affected cell survival, and ROS or GSH levels differently in H2O2-untreated, control CPAECs. The data suggest that the exposure of CPAECs to H2O2 caused the cell growth inhibition and cell death through GSH depletion. Furthermore, JNK inhibitor treatment further enhanced, whereas p38 inhibitors attenuated, these effects. Thus, the results of the present study suggest a specific protective role for the p38 inhibitor, and not the JNK inhibitor, against H2O2-induced cell growth inhibition and cell death.
Kich, Débora Mara; Bitencourt, Shanna; Caye, Bruna; Faleiro, Dalana; Alves, Celso; Silva, Joana; Pinteus, Susete; Mergener, Michelle; Majolo, Fernanda; Boligon, Aline Augusti; Santos, Roberto Christ Vianna; Pedrosa, Rui; de Souza, Claucia Fernanda Volken; Goettert, Márcia Inês
Calyptranthes tricona is a species (Myrtaceae) native to South Brazil. Plants belonging to this family are folkloric used for analgesia, inflammation, and infectious diseases. However, little is known about the toxic potential of C. tricona. The present study aimed to evaluate the antioxidant activity of C. tricona ethanol and hexane leaf extracts, as well as verify their effect on human lymphocytes and MCF-7 cells. The extracts were subjected to preliminary phytochemical screening, antioxidant activity using DPPH and ORAC methods. Genotoxic and mutagenic effects in cultured human lymphocytes were assessed using the comet assay and the micronucleus assay, respectively. In addition, cell viability by MTT assay and fluorometric analysis of mitochondrial potential and caspases-9 activity were performed in order to verify the possible effects of both extracts on H 2 O 2 -induced cell death of MCF-7 cells. Our findings revealed that the phenol content and the antioxidant activity were only present in the ethanol extract. Also, the phytochemical screening presented steroids, triterpenoids, condensed tannins, and flavones as the main compounds. However, both extracts were capable of inducing concentration-dependent DNA damage in human lymphocytes. When treating MCF-7 cells with the extracts, both of them inhibited MCF-7 cell death in response to oxidative stress through a decrease of mitochondrial depolarization and caspases-9 activity. Thus, our results need to be considered in future in vitro and in vivo studies of C. tricona effects. In the meanwhile, we recommend caution in the acute/chronic use of this homemade preparation for medicinal purpose.
Full Text Available Osteoarthritis (OA, one of the most common joint diseases with unknown etiology, is characterized by the progressive destruction of articular cartilage and the apoptosis of chondrocytes. The purpose of this study is to elucidate the molecular mechanisms of H2O2-mediated rabbit chondrocytes apoptosis. CCK-8 assay showed that H2O2 treatment induced a remarkable reduction of cell viability, which was further verified by the remarkable phosphatidylserine externalization after H2O2 treatment for 1 h, the typical characteristics of apoptosis. H2O2 treatment induced a significant dysfunction of mitochondrial membrane potential (ΔΨm, but did not induce casapse-9 activation, indicating that H2O2 treatment induced caspase-independent intrinsic apoptosis that was further verified by the fact that silencing of AIF but not inhibiting caspase-9 potently prevented H2O2-induced apoptosis. H2O2 treatment induced a significant increase of caspase-8 and -3 activation, and inhibition of caspase-8 or -3 significantly prevented H2O2-induced apoptosis, suggesting that the extrinsic pathway played an important role. Collectively, our findings demonstrate that H2O2 induces apoptosis via both the casapse-8-mediated extrinsic and the caspase-independent intrinsic apoptosis pathways in rabbit chondrocytes.
Zal, F; Khademi, F; Taheri, R; Mostafavi-Pour, Z
Oxidative stress and a disrupted antioxidant system are involved in a variety of pregnancy complications. In the present study, the role of vitamin E (Vit E) and folate as radical scavengers on the GSH homeostasis in stress oxidative induced in rat endometrial cells was investigated. Primary endometrial stromal cell cultures treated with 50 and 200 µM of H2O2 and evaluated the cytoprotective effects of Vit E (5 µM) and folate (0.01 µM) in H2O2-treated cells for 24 h. Following the exposure of endometrial cells to H2O2 alone and in the presence of Vit E and/or folate, cell survival, glutathione peroxidase (GPx) and glutathione reductase activities and the level of reduced glutathione (GSH) were measured. Cell adhesions comprise of cell attachment and spreading on collagen were determined. Flow cytometric analysis using annexin V was used to measure apoptosis. H2O2 treatment showed a marked decrease in cell viability, GPx and GR activities and the level of GSH. Although Vit E or folate had some protective effect, combination therapy with Vit E and folate attenuated all the changes due to H2O2 toxicity. An increasing number of alive cells was showed in the cells exposed to H2O2 (50 µM) accompanied by co-treatment with Vit E and folic acid. The present findings indicate that co-administration of Vit E and folate before and during pregnancy may maintain a viable pregnancy and contribute to its clinical efficacy for the treatment of some idiopathic infertility.
Blenn, Christian; Althaus, Felix R; Malanga, Maria
PAR [poly(ADP-ribose)] is a structural and regulatory component of multiprotein complexes in eukaryotic cells. PAR catabolism is accelerated under genotoxic stress conditions and this is largely attributable to the activity of a PARG (PAR glycohydrolase). To overcome the early embryonic lethality of parg-knockout mice and gain more insights into the biological functions of PARG, we used an RNA interference approach. We found that as little as 10% of PARG protein is sufficient to ensure basic cellular functions: PARG-silenced murine and human cells proliferated normally through several subculturing rounds and they were able to repair DNA damage induced by sublethal doses of H2O2. However, cell survival following treatment with higher concentrations of H2O2 (0.05-1 mM) was increased. In fact, PARG-silenced cells were more resistant than their wild-type counterparts to oxidant-induced apoptosis while exhibiting delayed PAR degradation and transient accumulation of ADP-ribose polymers longer than 15-mers at early stages of drug treatment. No difference was observed in response to the DNA alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine, suggesting a specific involvement of PARG in the cellular response to oxidative DNA damage.
de Oliveira, Marcos Roberto; Brasil, Flávia Bittencourt; Andrade, Cláudia Marlise Balbinotti
Mitochondria are the major site of ATP production in mammalian cells. Furthermore, these organelles are a source and a target of reactive oxygen species (ROS), such as radical anion superoxide (O 2 -· ) and hydrogen peroxide (H 2 O 2 ). The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is the master regulator of the mammalian redox biology and controls the expression of antioxidant and phase II detoxifying enzymes in several cell types. Naringenin (NGN, 5,7-dihydroxy-2-(4-hydroxyphenyl)-2,3-dihydrochromen-4-one), a flavanone, exhibits cytoprotective effects by acting as an antioxidant and anti-inflammatory agent. NGN is a potent activator of Nrf2. Nonetheless, it was not examine yet whether NGN would induce mitochondrial protection in cells under redox stress. Therefore, we investigate here whether Nrf2 would be involved in the mitochondrial protection elicited by NGN in SH-SY5Y cells exposed to H 2 O 2 . We observed that a pretreatment with NGN at 80 µM for 2 h reduced the levels of lipid peroxidation, protein carbonylation, and protein nitration in the membranes of mitochondria obtained from H 2 O 2 -treated SH-SY5Y cells. Additionally, NGN prevented the H 2 O 2 -induced impairment in the function of the enzymes aconitase, α-ketoglutarate dehydrogenase, and succinate dehydrogenase. The activites of the complexes I and V, as well as the production of ATP, were restored by NGN. NGN also suppressed the H 2 O 2 -induced mitochondria-related apoptosis. Interestingly, NGN promoted an increase in the levels of both total and mitochondrial glutathione (GSH). Silencing of Nrf2 abolished the protective effects induced by NGN. Overall, NGN induced mitochondrial protection by an Nrf2-dependent mechanism in H 2 O 2 -treated SH-SY5Y cells.
Lv, Runxiao; Du, Lili; Lu, Chunwen; Wu, Jinhui; Ding, Muchen; Wang, Chao; Mao, Ningfang; Shi, Zhicai
Allicin is a major bioactive ingredient of garlic and has a broad range of biological activities. Allicin has been reported to protect against cell apoptosis induced by H 2 O 2 in human umbilical vein endothelial cells. The present study evaluated the neuroprotective effect of allicin on the H 2 O 2 -induced apoptosis of rat pheochromocytoma PC12 cells in vitro and explored the underlying mechanism involved. PC12 cells were incubated with increasing concentrations of allicin and the toxic effect of allicin was measured by MTT assay. The cells were pretreated for 24 h with low dose (L-), medium dose (M-) and high dose (H-) of allicin, followed by exposure to 200 µM H 2 O 2 for 2 h, and the cell viability was examined by MTT assay. In addition, cell apoptosis rate was analyzed by Annexin V-FITC/PI assay, while intracellular reactive oxygen species (ROS) and mitochondrial transmembrane potential (∆ψm) were measured by flow cytometry. Bcl-2, Bax, cleaved-caspase-3 and cytochrome c (Cyt C) in the mitochondria were also examined by western blotting. The results demonstrated that 0.01 µg/ml (L-allicin), 0.1 µg/ml (M-allicin) and 1 µg/ml (H-allicin) were non-toxic doses of allicin. Furthermore, H 2 O 2 reduced cell viability, promoted cell apoptosis, induced ROS production and decreased ∆ψm. However, allicin treatment reversed the effect of H 2 O 2 in a dose-dependent manner. It was also observed that H 2 O 2 exposure significantly decreased Bcl-2 and mitochondrial Cyt C, while it increased Bax and cleaved-caspase-3, which were attenuated by allicin pretreatment. The results revealed that allicin protected PC12 cells from H 2 O 2 -induced cell apoptosis via the mitochondrial pathway, suggesting the potential neuroprotective effect of allicin against neurological diseases.
Full Text Available Oxidative stress-induced retinal pigment epithelial (RPE cell damage is an important factor in the pathogenesis of age-related macular degeneration (AMD. Previous studies have shown that RTA 408, a synthetic triterpenoid compound, potently activates Nrf2. This study aimed to investigate the protective effects of RTA 408 in cultured RPE cells during oxidative stress and to determine the effects of RTA 408 on Nrf2 and its downstream target genes. Primary human RPE cells were pretreated with RTA 408 and then incubated in 200 μM H2O2 for 6 h. Cell viability was measured with the WST-8 assay. Apoptosis was quantitatively measured by annexin V/propidium iodide (PI double staining and Hoechst 33342 fluorescent staining. Reduced (GSH and oxidized glutathione (GSSG were measured using colorimetric assays. Nrf2 activation and its downstream effects on phase II enzymes were examined by Western blot. Treatment of RPE cells with nanomolar ranges (10 and 100 nM of RTA 408 markedly attenuated H2O2-induced viability loss and apoptosis. RTA 408 pretreatment significantly protected cells from oxidative stress-induced GSH loss, GSSG formation and decreased ROS production. RTA 408 activated Nrf2 and increased the expression of its downstream genes, such as HO-1, NQO1, SOD2, catalase, Grx1, and Trx1. Consequently, the enzyme activities of NQO1, Grx1, and Trx1 were fully protected by RTA 408 pretreatment under oxidative stress. Moreover, knockdown of Nrf2 by siRNA significantly reduced the cytoprotective effects of RTA 408. In conclusion, our data suggest that RTA 408 protect primary human RPE cells from oxidative stress-induced damage by activating Nrf2 and its downstream genes.
Tian, Youqing; Daoud, Abdelkader; Shang, Jing
Reactive oxygen species (ROS) are involved in myocardial injury. ROS are known to inactivate lipid phosphatase and tension homolog on chromosome 10 (PTEN), an enzyme that increases apoptosis in neonatal cardiomyocytes. BpV(pic) and bpV(phen), two bisperoxovanadium molecules and PTEN inhibitors, may be involved in limiting myocardial infarction. To compare the protective effects of bpV(pic) and bpV(phen) on ROS-induced cardiomyocyte injury and their possible mechanisms, we selected two popular models of hypoxia/reoxygenation (H/R) and H2O2-induced injury in H9c2 cardiomyoblasts to investigate their effects against injury. We found that pre-treatment with bpV(pic) and bpV(phen) increased the viability and protected the morphology of H9c2 cells under the conditions of H/R and H2O2 by inhibiting LDH release, apoptosis and caspases 3/8/9 activities. However, their respective inhibitory abilities in the two models were different, suggesting that the quantity of ROS from the two models might be different. However, the conflict between ROS and PTEN may affect the action of bpV(pic) and bpV(phen). Taken together, the results demonstrate that bpV(pic) and bpV(phen) have inhibitory effects on oxidative stress-induced cardiomyocyte injury that may be partially modulated by the action of ROS on PTEN.
Shekoohiyan, Sakine; Moussavi, Gholamreza; Naddafi, Kazem
A bacterial peroxidase-mediated oxidizing process was developed for biodegrading total petroleum hydrocarbons (TPH) in a sequencing batch reactor (SBR). Almost complete biodegradation (>99%) of high TPH concentrations (4g/L) was attained in the bioreactor with a low amount (0.6mM) of H2O2 at a reaction time of 22h. A specific TPH biodegradation rate as high as 44.3mgTPH/gbiomass×h was obtained with this process. The reaction times required for complete biodegradation of TPH concentrations of 1, 2, 3, and 4g/L were 21, 22, 28, and 30h, respectively. The catalytic activity of hydrocarbon catalyzing peroxidase was determined to be 1.48U/mL biomass. The biodegradation of TPH in seawater was similar to that in fresh media (no salt). A mixture of bacteria capable of peroxidase synthesis and hydrocarbon biodegradation including Pseudomonas spp. and Bacillus spp. were identified in the bioreactor. The GC/MS analysis of the effluent indicated that all classes of hydrocarbons could be well-degraded in the H2O2-induced SBR. Accordingly, the peroxidase-mediated process is a promising method for efficiently biodegrading concentrated TPH-laden saline wastewater. Copyright © 2016 Elsevier B.V. All rights reserved.
Wang, Liu; Zhao, Ruirui; Zheng, Yanyan; Chen, Lin; Li, Rui; Ma, Junfei; Hong, Xiaofeng; Ma, Peihua; Sheng, Jiping; Shen, Lin
Hydrogen peroxide (H2O2) acts as a signaling molecule in response to cold stress. Mitogen-activated protein kinases (MAPKs) and C-repeat/dehydration-responsive factor (CBF) play important roles in cold response regulation. To investigate the roles of MAPKs and CBF in H2O2-induced chilling tolerance, tomato (Solanum lycopersicum cv. Ailsa Craig) plants were treated with 1 mM H2O2 before chilling treatment. The results showed that H2O2 treatment protected subcellular structure, increased concentrations of abscisic acid (ABA), zeatin riboside (ZR), and methyl jasmonate (MeJA), but decreased the concentration of gibberellic acid (GA3). Furthermore, 1 mM H2O2 treatment enhanced the activities of antioxidant enzymes. Meanwhile, relative expressions of SlMAPK1/2/3 and SlCBF1 in H2O2-treated plants were higher than those in the control. Our findings suggest that H2O2 treatment might enhance the chilling tolerance of tomato plants by activating SlMAPK1/2/3 and SlCBF1 gene expression and by regulating phytohormone concentrations and antioxidant enzyme activities.
Tang, Bao; Zhang, Dan; Li, Sha; Xu, Zongqi; Feng, Xiaohai; Xu, Hong
Effects of reactive oxygen species (ROS) on cell growth and poly(γ-glutamic acid) (γ-PGA) synthesis were studied by adding hydrogen peroxide to a medium of Bacillus subtilis NX-2. After optimizing the addition concentration and time of H 2 O 2 , a maximum concentration of 33.9 g/L γ-PGA was obtained by adding 100 µM H 2 O 2 to the medium after 24 H. This concentration was 20.6% higher than that of the control. The addition of diphenyleneiodonium chloride (ROS inhibitor) can interdict the effect of H 2 O 2 -induced ROS. Transcriptional levels of the cofactors and relevant genes were also determined under ROS stress to illustrate the possible metabolic mechanism contributing to the improve γ-PGA production. The transcriptional levels of genes belonging to the tricarboxylic acid cycle and electron transfer chain system were significantly increased by ROS, which decreased the NADH/NAD + ratio and increased the ATP levels, thereby providing more reducing power and energy for γ-PGA biosynthesis. The enhanced γ-PGA synthetic genes also directly promoted the formation of γ-PGA. This study was the first to use the ROS control strategy for γ-PGA fermentation and provided valuable information on the possible mechanism by which ROS regulated γ-PGA biosynthesis in B. subtilis NX-2. © 2015 International Union of Biochemistry and Molecular Biology, Inc.
Varela, Diego; Simon, Felipe; Olivero, Pablo
activation. The aim of this study was to determine the signalling pathways responsible for H(2)O(2)-induced VSOR Cl(-) channel activation. In rat hepatoma (HTC) cells, H(2)O(2) elicited a transient increase in tyrosine phosphorylation of phospholipase Cgamma1 (PLCgamma1) that was blocked by PP2, a Src......-family protein kinases inhibitor. Also, H(2)O(2) triggered an increase in cytosolic [Ca(2+)] that paralleled the time course of PLCgamma1 phosphorylation. The H(2)O(2)-induced [Ca(2+)](i) rise was prevented by the generic phospholipase C (PLC) inhibitor U73122 and the inositol 1,4,5-trisphosphate-receptor (IP(3...
Shi, Xingxing; Li, Wenjing; Liu, Honghong; Yin, Deling; Zhao, Jing
Cardiac stem cells (CSCs)-based therapy provides a promising avenue for the management of ischemic heart diseases. However, engrafted CSCs are subjected to acute cell apoptosis in the ischemic microenvironment. Here, stem cell antigen 1 positive (Sca-1+) CSCs proved to own therapy potential were cultured and treated with H2O2 to mimic the ischemia situation. As autophagy inhibitor, 3-methyladenine (3MA), inhibited H2O2-induced CSCs apoptosis, thus we demonstrated that H2O2 induced autophagy-dependent apoptosis in CSCs, and continued to find key proteins responsible for the crosstalk between autophagy and apoptosis. Nuclear Receptor Subfamily 4 Group A Member 2 (NR4A2), increased upon cardiomyocyte injury with unknown functions in CSCs, was increased by H2O2. NR4A2 siRNA attenuated H2O2 induced autophagy and apoptosis in CSCs, which suggested an important role of NR4A2 in CSCs survival in ischemia conditions. Reactive oxygen species (ROS) and NF-κB (P65) subunit were both increased by H2O2. Either the ROS scavenger, N-acetyl-l-cysteine (NAC) or NF-κB signaling inhibitor, bay11-7082 could attenuate H2O2-induced autophagy and apoptosis in CSCs, which suggested they were involved in this process. Furthermore, NAC inhibited NF-κB activities, while bay11-7082 inhibited NR4A2 expression, which revealed a ROS/NF-κB/NR4A2 pathway responsible for H2O2-induced autophagy and apoptosis in CSCs. Our study supports a new clue enhancing the survival rate of CSCs in the infarcted myocardium for cell therapy in ischemic cardiomyopathy.
Varela, Diego; Simon, Felipe; Olivero, Pablo; Armisén, Ricardo; Leiva-Salcedo, Elías; Jørgensen, Finn; Sala, Francisco; Stutzin, Andrés
Volume-sensitive outwardly rectifying (VSOR) Cl(-) channels participate in several physiological processes such as regulatory volume decrease, cell cycle regulation, proliferation and apoptosis. Recent evidence points to a significant role of hydrogen peroxide (H(2)O(2)) in VSOR Cl(-) channel activation. The aim of this study was to determine the signalling pathways responsible for H(2)O(2)-induced VSOR Cl(-) channel activation. In rat hepatoma (HTC) cells, H(2)O(2) elicited a transient increase in tyrosine phosphorylation of phospholipase Cgamma1 (PLCgamma1) that was blocked by PP2, a Src-family protein kinases inhibitor. Also, H(2)O(2) triggered an increase in cytosolic [Ca(2+)] that paralleled the time course of PLCgamma1 phosphorylation. The H(2)O(2)-induced [Ca(2+)](i) rise was prevented by the generic phospholipase C (PLC) inhibitor U73122 and the inositol 1,4,5-trisphosphate-receptor (IP(3)R) blocker 2-APB. In line with these results, manoeuvres that prevented PLCgamma1 activation and/or [Ca(2+)](i) rise, abolished H(2)O(2)-induced VSOR Cl(-) currents. Furthermore, in cells that overexpress a phosphorylation-defective dominant mutant of PLCgamma1, H(2)O(2) did not induce activation of VSOR Cl(-) currents. All these H(2)O(2)-induced effects were independent of extracellular Ca(2+). Our findings suggest that activation of PLCgamma1 and subsequent Ca(2+)(i) mobilisation mediate H(2)O(2)-induced VSOR Cl(-) currents, indicating that H(2)O(2) operates via redox-sensitive signalling pathways akin to those activated by osmotic challenges.
Full Text Available Parkinson’s disease (PD is one of the most common neurodegenerative diseases. Recent studies suggest that sulfated hetero-polysaccharides (UF protect against developing PD. However, the detailed mechanisms of how UF suppress neuronal death have not been fully elucidated. We investigated the cytoprotective mechanisms of UF using human dopaminergic neuroblastoma SH-SY5Y cells as a PD model. UF prevented H2O2-induced apoptotic cell death in SH-SY5Y cells in a dose-dependent manner. An examination of the PI3K/Akt upstream pathway revealed that UF-pretreated cells showed a decreased relative density of Akt, PI3K, and TrkA, and increased the phosphorylation of Akt, PI3K, and NGF; the PI3K inhibitor, LY294002, partially prevented this effect. An examination of the PI3K/Akt downstream pathway revealed the increased expression of the apoptosis-associated markers Bax, p53, CytC, and GSK3β, and the decreased expression of Bcl-2 in UF-treated cells. UF-treated cells also exhibited decreased caspase-3, caspase-8, and caspase-9 activities, which induced cell apoptosis. Our results demonstrate that UF affect the PI3K/Akt pathway, as well as downstream signaling. Therefore, the UF-mediated activation of PI3K/Akt could provide a new potential therapeutic strategy for neurodegenerative diseases associated with oxidative injury. These findings contribute to a better understanding of the critical roles of UF in the treatment of PD.
Yasuda, Jumpei; Okada, Muneyoshi; Yamawaki, Hideyuki
Tumstatin, a cleaved fragment of α3 chain of type IV collagen, is an endogenous anti-angiogenetic peptide. Although the expression level of tumstatin changes in the heart tissues of certain experimental cardiac disease models, its effect on cardiomyocytes has not been clarified. In this study, we examined the effects of T3 peptide, an active subfragment of tumstatin, on hydrogen peroxide (H 2 O 2 )-induced cell death in H9c2 cardiomyoblasts. Cell viability was examined by a cell counting assay. Staining using 4', 6-diamidino-2-phenylindole was performed to observe nuclear morphology. Western blotting was performed to examine cleaved caspase-3 expression. Mitochondrial membrane potential and morphology were detected by a Mito Tracker Red staining. Intracellular reactive oxygen species production was examined by 2', 7'-dichlorodihydrofluorescein diacetate staining. T3 peptide (300, 1000ng/ml) suppressed H 2 O 2 (1mM)-induced cell death, apoptotic changes of nuclei and cleaved caspas-3 expression in a concentration-dependent manner. T3 peptide also inhibited H 2 O 2 -induced loss of mitochondrial membrane potential, mitochondrial fission and reactive oxygen species production. Cilengitide, an integrin α v β 3 /α v β 5 inhibitor, prevents the inhibitory effect of T3 peptide on H 2 O 2 -induced reactive oxygen species production. In conclusion, T3 peptide inhibits H 2 O 2 -induced apoptosis at least partly via the inhibition of intracellular reactive oxygen species production through the action on integrin. Copyright © 2017 Elsevier B.V. All rights reserved.
Full Text Available Yong-Pan Huang,1,* Fen-Fei Gao,1,* Bin Wang,1 Fu-Chun Zheng,2 Yan-Mei Zhang,1 Yi-Cun Chen,1 Zhan-Qin Huang,1 Yan-Shan Zheng,1 Shu-Ping Zhong,3 Gang-Gang Shi1,4 1Department of Pharmacology, 2Department of Pharmacy, First Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, People's Republic of China; 3Department of Biochemistry and Molecular Biology, University of Southern California, Los Angeles, CA, USA; 4Department of Cardiovascular Diseases, First Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, People's Republic of China *These authors contributed equally to this work Abstract: N-n-butyl haloperidol iodide (F2, a novel compound, has shown palliative effects in myocardial ischemia/reperfusion (I/R injury. In this study, we investigated the effects of F2 on the extracellular signal-regulated kinase kinase (MEK/extracellular signal-regulated kinase (ERK/Na+/H+ exchanger (NHE/Na+/Ca2+ exchanger (NCX signal-transduction pathway involved in H2O2-induced Ca2+ overload, in order to probe the underlying molecular mechanism by which F2 antagonizes myocardial I/R injury. Acute exposure of rat cardiac myocytes to 100 µM H2O2 increased both NHE and NCX activities, as well as levels of phosphorylated MEK and ERK. The H2O2-induced increase in NCX current (INCX was nearly completely inhibited by the MEK inhibitor U0126 (1,4-diamino-2,3-dicyano-1,4-bis[o-aminophenylmercapto]butadiene, but only partly by the NHE inhibitor 5-(N,N-dimethyl-amiloride (DMA, indicating the INCX increase was primarily mediated by the MEK/mitogen-activated protein kinase (MAPK pathway, and partially through activation of NHE. F2 attenuated the H2O2-induced INCX increase in a concentration-dependent manner. To determine whether pathway inhibition was H2O2-specific, we examined the ability of F2 to inhibit MEK/ERK activation by epidermal growth factor (EGF, and NHE activation by angiotensin II. F2 not only inhibited H2O2-induced and
Deng, Xiangyu; Chen, Sheng; Zheng, Dong; Shao, Zengwu; Liang, Hang; Hu, Hongzhi
Icariin is a prenylated flavonol glycoside derived from the Chinese herb Epimedium sagittatum. This study investigated the mechanism by which icariin prevents H2O2-induced apoptosis in rat nucleus pulposus (NP) cells. NP cells were isolated from the rat intervertebral disc and they were divided into five groups after 3 passages: (A) blank control; (B) 200 μM H2O2; (C) 200 μM H2O2 + 20 μM icariin; (D) 20 μM icariin + 200 μM H2O2 + 25 μM LY294002; (E) 200 μM H2O2 + 25 μM LY294002. LY294002 is a selective inhibitor of the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway. NP cell viability, apoptosis rate, intracellular reactive oxygen species levels, and the expression of AKT, p-AKT, p53, Bcl-2, Bax, caspase-3 were estimated. The results show that, compared with the control group, H2O2 significantly increased NP cell apoptosis and the level of intracellular ROS. Icariin pretreatment significantly decreased H2O2-induced apoptosis and intracellular ROS and upregulated p-Akt and BCL-2 and downregulated caspase-3 and Bax. LY294002 abolished the protective effects of icariin. Our results show that icariin can attenuate H2O2-induced apoptosis in rat nucleus pulposus cells and PI3K/AKT pathway is at least partly included in this protection effect.
Yang, Xian-Wen; He, Hong-Ping; Du, Zhi-Zhi; Liu, Hai-Yang; Di, Ying-Tong; Ma, Yan-Lin; Wang, Fang; Lin, Hua; Zuo, Yi-Qing; Li, Ling; Hao, Xiao-Jiang
Eight new lignan glucosides, tarennanosides A-H (1-8, resp.), were isolated from the whole plant of Tarenna attenuata, together with three known compounds, fernandoside, (-)-lyoniresinol, and (-)-isolariciresinol. The planar structures of new compounds were elucidated mainly by analysis of physical and spectroscopic data, and the absolute configurations were determined by acid hydrolysis as well as CD spectroscopy. Compounds 1 and 2 exhibited potent antioxidant activities against H2O2-induced impairment in PC12 cells. Preliminary mechanism study by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method showed that these two compounds could act as radical scavengers.
Wu, Jian-Zhang; Cheng, Chan-Chan; Shen, Lai-Lai; Wang, Zhan-Kun; Wu, Shou-Biao; Li, Wu-Lan; Chen, Su-Hua; Zhou, Rong-Ping; Qiu, Pei-Hong
Chalcone derivatives (E)-3-(4-hydroxy-3-methoxyphenyl)-1-(4-methoxyphenyl) prop-2-en-1-one and (E)-3-(4-hydroxyphenyl)-1-(4-methoxyphenyl) prop-2-en-1-one (Compounds 1 and 2) have been demonstrated to be potent anti-inflammatory agents in our previous study. In light of the relationship of intracellular mechanisms between anti-inflammatories and antioxidants, we further designed and synthesized a series of chalcone derivatives based on 1 and 2, to explore their antioxidant efficacy. The majority of the derivatives exhibited strong protective effects on PC12 (PC12 rat pheochromocytoma) cells exposed to H2O2, and all compounds were nontoxic. A preliminary structure-activity relationship was proposed. Compounds 1 and 1d ((E)-2-methoxy-4-(3-(4-methoxyphenyl)-3-oxoprop-1-en-1-yl) phenyl acrylate) exerted the action in a good dose-dependent manner. Quantitative RT-PCR (qRT-PCR) and western blot analysis showed that 1 and 1d significantly improve the expression of nuclear factor erythroid 2 p45-related factor 2 (Nrf2)-dependent antioxidant genes g-Glutamylcysteine Ligase Catalytic Subunit (GCLC) and heme oxygenase-1 (HO-1) and their corresponding proteins (γ-glutamyl cysteine synthase (γ-GCS) and HO-1) in PC12 cells. Inhibition of GCLC and HO-1 by specific inhibitors, l-buthionine-S-sulfoximine (BSO) and zinc protoporphyrin (ZnPP), respectively, partially reduce the protective effect of 1 and 1d. These data present a series of novel chalcone analogs, especially compounds 1 and 1d, as candidates for treating oxidative stress-related disease by activating the Nrf2-antioxidant responsive element (ARE) pathway. PMID:25318055
Qi, Zhi-Lin; Liu, Yin-Hua; Qi, Shi-Mei; Ling, Lie-Feng; Feng, Zun-Yong; Li, Qiang
To investigate the molecular mechanism by which salidroside protects PC12 cells from H2O2-induced apoptosis. PC12 cells cultured in DMEM supplemented with 10% horse serum and 5% fetal bovine serum were pretreated with different doses of salidroside for 2 h and then stimulated with H2O2 for different lengths of time. The expression levels of PARP and caspase 3 and the phosphorylation of p38, ERK and JNK were determined with Western blotting. The cell nuclear morphology was observed after DAPI staining. The production of ROS was detected using a ROS detection kit, and the levels of gp91(phox) and p47(phox) in the membrane and cytoplasm were detected by membrane-cytoplasm separation experiment; the binding between gp91(phox) and p47(phox) was assayed by coimmunoprecipitation experiment. Salidroside dose-dependently suppressed cell apoptosis, lowered phosphorylation levels of p38, ERK and JNK, inhibited the production of ROS, reduced the binding between gp91(phox) and p47(phox), and inhibited the activity of NOX2 in PC12 cells exposed to H2O2. Salidroside protects PC12 cells from H2O2-induced apoptosis at least partly by suppressing NOX2-ROS-MAPKs signaling pathway.
Miranda, Daniel D. C; Arçari, Demétrius P; Pedrazzoli, José; Carvalho, Patrícia de O; Cerutti, Suzete M; Bastos, Deborah H. M; Ribeiro, Marcelo L
.... Since oxidative DNA damage is involved in various pathological states such as cancer, the aim of this study was to evaluate the antioxidant activity of mate tea as well as the ability to influence...
Hu, Junzheng; Cui, Weiding; Ding, Wenxiao; Gu, Yanqing; Wang, Zhen; Fan, Weimin
Chondrocyte apoptosis is closely related to the development and progression of osteoarthritis. Global adiponectin (gAPN), secreted from adipose tissue, possesses potent anti-inflammatory and antiapoptotic properties in various cell types. This study aimed to investigate the role of autophagy induced by gAPN in the suppression of H2O2-induced apoptosis and the potential mechanism of gAPN-induced autophagy in chondrocytes. H2O2 was used to induce apoptotic injury in rat chondrocytes. CCK-8 assay was performed to determine the viability of cells treated with different concentrations of gAPN with or without H2O2. Cell apoptosis was detected by flow cytometry and TUNEL staining. Mitochondrial membrane potential was examined using JC-1 fluorescence staining assay. The autophagy inhibitors 3-MA and Bafilomycin A1 were used to treat cells and then evaluate the effect of gAPN-induced autophagy. To determine the downstream pathway, chondrocytes were preincubated with the AMPK inhibitor Compound C. Beclin-1, LC3B, P62 and apoptosis-related proteins were identified by Western blot analysis. H2O2 (400 µM)-induced chondrocytes apoptosis and caspase-3 activation were attenuated by gAPN (0.5 µg/mL). gAPN increased Bcl-2 expression and decreased Bax expression. The loss of mitochondrial membrane potential induced by H2O2 was also abolished by gAPN. Furthermore, the antiapoptotic effect of gAPN was related to gAPN-induced autophagy by increased formation of Beclin-1 and LC3B and P62 degradation. In particular, the inhibition of gAPN-induced autophagy by 3-MA prevented the protective effect of gAPN on apoptosis induced by H2O2. Moreover, gAPN increased p-AMPK expression and decreased p-mTOR expression. Compound C partly suppressed the expression of autophagy-related proteins and restored the expression of p-mTOR suppressed by gAPN. Thus, the AMPK/mTOR pathway played an important role in the induction of autophagy and protection of H2O2-induced chondrocytes apoptosis by gAPN. g
Full Text Available Background/Aims: Chondrocyte apoptosis is closely related to the development and progression of osteoarthritis. Global adiponectin (gAPN, secreted from adipose tissue, possesses potent anti-inflammatory and antiapoptotic properties in various cell types. This study aimed to investigate the role of autophagy induced by gAPN in the suppression of H2O2-induced apoptosis and the potential mechanism of gAPN-induced autophagy in chondrocytes. Methods: H2O2 was used to induce apoptotic injury in rat chondrocytes. CCK-8 assay was performed to determine the viability of cells treated with different concentrations of gAPN with or without H2O2. Cell apoptosis was detected by flow cytometry and TUNEL staining. Mitochondrial membrane potential was examined using JC-1 fluorescence staining assay. The autophagy inhibitors 3-MA and Bafilomycin A1 were used to treat cells and then evaluate the effect of gAPN-induced autophagy. To determine the downstream pathway, chondrocytes were preincubated with the AMPK inhibitor Compound C. Beclin-1, LC3B, P62 and apoptosis-related proteins were identified by Western blot analysis. Results: H2O2 (400 µM-induced chondrocytes apoptosis and caspase-3 activation were attenuated by gAPN (0.5 µg/mL. gAPN increased Bcl-2 expression and decreased Bax expression. The loss of mitochondrial membrane potential induced by H2O2 was also abolished by gAPN. Furthermore, the antiapoptotic effect of gAPN was related to gAPN-induced autophagy by increased formation of Beclin-1 and LC3B and P62 degradation. In particular, the inhibition of gAPN-induced autophagy by 3-MA prevented the protective effect of gAPN on apoptosis induced by H2O2. Moreover, gAPN increased p-AMPK expression and decreased p-mTOR expression. Compound C partly suppressed the expression of autophagy-related proteins and restored the expression of p-mTOR suppressed by gAPN. Thus, the AMPK/mTOR pathway played an important role in the induction of autophagy and protection of
Sohn, Uy Soo; Lee, Se Eun; Lee, Sung Hee; Nam, Yoonjin; Hwang, Wan Kyunn; Sohn, Uy Dong
Quercetin-3-O-β-D-glucuronopyranoside (QGC) is a flavonoid glucoside extracted from Rumex Aquaticus. Recent studies have shown that QGC exhibits anti-inflammatory, anti-oxidateve effect in vivo and cytoprotective effect in vitro. Reactive oxygen species (ROS), at low concentration, play role as a primary signal or second messenger, however, at high concentration, ROS are cytotoxic. In this study, we investigated the protective mechanism of QGC in H2O2-induced injury of Feline Esophageal Epithelial Cells. Primary-cultured feline esophagus cells were identified by an indirect immunofluorescent staining method using a cytokeratin monoclonal antibody. Cell viability was determined by the conventional MTT reduction assay. Western blot analysis was performed with specific antibodies to investigate the activation of MAPKs, NF-κB, and IκB-α, and the expression of COX-2. When the cells were exposed to 600 μM H2O2 medium for 24 h, cell viability decreased to 54 %. However, when cells were pretreated with 50-150 μM QGC for 12 h, the viability of cells exposed to H2O2 significantly increased in the dose dependent manner. QGC (50 μM, 12 h) also inhibited the expression of COX-2 induced by 10 μM H2O2 for 24 h. We found that treatment of H2O2 activated p38 MAPK and JNK, but not ERK. However QGC inhibited the H2O2-induced p38 MAPK and JNK phosphorylation. In addition, NF-κB was activated by H2O2 and translocated into the nucleus, but QGC inhibited the activation of NF-κB by blocking degradation of IκB. These data suggest that QGC reduces H2O2-induced COX-2 production by modulating the p38 MAPK, JNK, NF-κB signal pathway in feline esophageal epithelial cells.
Wei, Ri-Bao; Wang, Yong-Xin; Cao, Li; Zhuo, Li; Fu, Bo; Li, Ping
The aim of this study was to explore the protective effect of compound tianpupian (TPP) against (2)O(2)-induced the apoptosis of murine splenic lymphocytes and its mechanism. The cell apoptosis rate was detected by MTT method; the cell apoptosis and mitochondrial membrance potential were detected by flow cytometry (FCM) with Annexi-V/PI double staining and JC-1 staining method, respectively; and caspase 3 relative activity was determined by colorimetry. The results indicated that after treating with (2)O(2), the absorbance value of cultured lymphocytes and the red/green ratio of JC-1 were reduced, and the apoptotic rate and caspase 3 activity were increased, coculture of (2)O(2)-treated cells with compound TPP increased the cell absorbance ratio and red/green rate of JC-1, while reduced the apoptosis rate and caspase 3 activity. It is concluded that compound TPP alleviates intracellular oxidative damages and dose-dependently inhibited apoptosis of murine splenic lymphocytes through reducing mitochondrial membrane potential and inhibiting caspase 3 activity. This suggests that compound TPP is a potential anti-apoptotic agent.
Full Text Available Oxidative stress, as mediated by ROS, is a significant factor in initiating the development of age-associated cataracts; D-limonene is a common natural terpene with powerful antioxidative properties which occurs naturally in a wide variety of living organisms. It has been shown to have antioxidant effect; we found that D-limonene can effectively prevent the oxidative damage caused by H2O2 and propose that the main mechanism underlying the inhibitory effects of D-limonene is the inhibition of HLECs apoptosis. In the present study, we used confocal-fluorescence microscopy, flow cytometry analysis, Hoechst staining, H2DCFDA staining, transmission electron microscopy, and immunoblot analysis; the results revealed that slightly higher concentrations of D-limonene (125–1800 μM reduced the H2O2-induced ROS generation and inhibited the H2O2-induced caspase-3 and caspase-9 activation and decreased the Bcl-2/Bax ratio. Furthermore, it inhibited H2O2-induced p38 MAPK phosphorylation. Thus, we conclude that D-limonene could effectively protect HLECs from H2O2-induced oxidative stress and that its antioxidative effect is significant, thereby increasing the cell survival rate.
Jo, Hyo Sang; Kim, Dae Won; Shin, Min Jea; Cho, Su Bin; Park, Jung Hwan; Lee, Chi Hern; Yeo, Eun Ji; Choi, Yeon Joo; Yeo, Hyeon Ji; Sohn, Eun Jeong; Son, Ora; Cho, Sung-Woo; Kim, Duk-Soo; Yu, Yeon Hee; Lee, Keun Wook; Park, Jinseu; Eum, Won Sik; Choi, Soo Young
Oxidative stress plays an important role in the progression of various neuronal diseases including ischemia. Heat shock protein 22 (HSP22) is known to protect cells against oxidative stress. However, the protective effects and mechanisms of HSP22 in hippocampal neuronal cells under oxidative stress remain unknown. In this study, we determined whether HSP22 protects against hydrogen peroxide (H2O2)-induced oxidative stress in HT-22 using Tat-HSP22 fusion protein. We found that Tat-HSP22 transduced into HT-22 cells and that H2O2-induced cell death, oxidative stress, and DNA damage were significantly reduced by Tat-HSP22. In addition, Tat-HSP22 markedly inhibited H2O2-induced mitochondrial membrane potential, cytochrome c release, cleaved caspase-3, and Bax expression levels, while Bcl-2 expression levels were increased in HT-22 cells. Further, we showed that Tat-HSP22 transduced into animal brain and inhibited cleaved-caspase-3 expression levels as well as significantly inhibited hippocampal neuronal cell death in the CA1 region of animals in the ischemic animal model. In the present study, we demonstrated that transduced Tat-HSP22 attenuates oxidative stress-induced hippocampal neuronal cell death through the mitochondrial signaling pathway and plays a crucial role in inhibiting neuronal cell death, suggesting that Tat-HSP22 protein may be used to prevent oxidative stress-related brain diseases including ischemia.
Full Text Available Intracellular calcium concentration ([Ca(2+]i plays an important role in regulating most cellular processes, including apoptosis and survival, but its alterations are different and complicated under diverse conditions. In this study, we focused on the [Ca(2+]i and its control mechanisms in process of hydrogen peroxide (H2O2-induced apoptosis of primary cultured Sprague-Dawley (SD rat retinal cells and 17β-estradiol (βE2 anti-apoptosis. Fluo-3AM was used as a Ca(2+ indicator to detect [Ca(2+]i through fluorescence-activated cell sorting (FACS, cell viability was assayed using MTT assay, and apoptosis was marked by Hoechst 33342 and annexin V/Propidium Iodide staining. Besides, PI3K activity was detected by Western blotting. Results showed: a 100 μM H2O2-induced retinal cell apoptosis occurred at 4 h after H2O2 stress and increased in a time-dependent manner, but [Ca(2+]i increased earlier at 2 h, sustained to 12 h, and then recovered at 24 h after H2O2 stress; b 10 μM βE2 treatment for 0.5-24 hrs increased cell viability by transiently increasing [Ca(2+]i, which appeared only at 0.5 h after βE2 application; c increased [Ca(2+]i under 100 µM H2O2 treatment for 2 hrs or 10 µM βE2 treatment for 0.5 hrs was, at least partly, due to extracellular Ca(2+ stores; d importantly, the transiently increased [Ca(2+]i induced by 10 µM βE2 treatment for 0.5 hrs was mediated by the phosphatidylinositol-3-kinase (PI3K and gated by the L-type voltage-gated Ca(2+ channels (L-VGCC, but the increased [Ca(2+]i induced by 100 µM H2O2 treatment for 2 hrs was not affected; and e pretreatment with 10 µM βE2 for 0.5 hrs effectively protected retinal cells from apoptosis induced by 100 µM H2O2, which was also associated with its transient [Ca(2+]i increase through L-VGCC and PI3K pathway. These findings will lead to better understanding of the mechanisms of βE2-mediated retinal protection and to exploration of the novel therapeutic strategies for retina
Full Text Available Resveratrol, a polyphenol presents in grapes and wine, displays antioxidant and anti-inflammatory properties and cytoprotective effect in brain pathologies associated to oxidative stress and neurodegeneration. In previous work, we demonstrated that resveratrol exerts neuroglial modulation, improving glial functions, mainly related to glutamate metabolism. Astrocytes are a major class of glial cells and regulate neurotransmitter systems, synaptic processing, energy metabolism and defense against oxidative stress. This study sought to determine the protective effect of resveratrol against hydrogen peroxide (H2O2-induced cytotoxicity in C6 astrocyte cell line, an astrocytic lineage, on neurochemical parameters and their cellular and biochemical mechanisms. H2O2 exposure increased oxidative-nitrosative stress, iNOS expression, cytokine proinflammatory release (TNFα levels and mitochondrial membrane potential dysfunction and decreased antioxidant defenses, such as SOD, CAT and creatine kinase activity. Resveratrol strongly prevented C6 cells from H2O2-induced toxicity by modulating glial, oxidative and inflammatory responses. Resveratrol per se increased heme oxygenase 1 (HO1 expression and extracellular GSH content. In addition, HO1 signaling pathway is involved in the protective effect of resveratrol against H2O2-induced oxidative damage in astroglial cells. Taken together, these results show that resveratrol represents an important mechanism for protection of glial cells against oxidative stress.
Xu, Jun; Wu, Liang; Zhang, Yiming; Gu, Huijie; Huang, Zhongyue; Zhou, Kaifeng; Yin, Xiaofan
The present study tested the potential effect of OSU53, a novel AMPK activator, against hydrogen peroxide (H2O2)-induced spinal cord neuron damages. Treatment with OSU53 attenuated H2O2-induced death and apoptosis of primary murine spinal cord neurons. OSU53 activated AMPK signaling, which is required for its actions in spinal cord neurons. The AMPK inhibitor Compound C or AMPKα1 siRNA almost abolished OSU53-mediated neuroprotection against H2O2. On the other hand, sustained-activation of AMPK by introducing the constitutive-active AMPKα1 mimicked OSU53's actions, and protected spinal cord neurons from oxidative stress. OSU53 significantly attenuated H2O2-induced reactive oxygen species production, lipid peroxidation and DNA damages in spinal cord neurons. Additionally, OSU53 increased NADPH content and heme oxygenase-1 mRNA expression in H2O2-treated spinal cord neurons. Together, we indicate that targeted-activation of AMPK by OSU53 protects spinal cord neurons from oxidative stress.
Full Text Available AIM: To explore the effect of different concentrations of salidroside on H2O2 induced oxidative stress damage in human lens epithelium cells(HLEC. METHODS: HLEC were cultured and divided into negative control group: cultured in normal cultivation; oxidative damage group: treated with 100μmol/L H2O2 for 12h; Salidroside low concentration group: 10μmol/L salidroside treated for 24h and H2O2 treated for 12h; Salidroside high concentration group: 100μmol/L salidroside treated for 24h and H2O2 treated for 12h. MTT method was applied to observe the effect of salidroside on HLEC survival rate. Morphological change of each group were observed and recorded under inverted microscope. DCFH-DA fluorescent probe was applied to detect intracellular ROS changes; content of malondialdehyde(MDA, superoxide dismutase(SODand glutathione peroxidase(GSH-Pxin supernatants were detected by pectrophotometer. RESULTS: Salidroside obviously inhibited H2O2-induced HLEC vitality decline, inhibited ROS generation in cells, causing SOD, GSH-Px levels increased and MDA levels decreased. CONCLUSION: Salidroside inhibited H2O2 induced HLEC injury by decreasing the intracellular MDA content levels and increasing SOD, GSH-Px content levels, which conclude that salidroside may have a certain role in the treatment of HLEC damage.
Ou, Zong-Quan; Rades, Thomas; McDowell, Arlene
-induced senescence by mediating oxidative stress. Premature senescence of young WI-38 cells was induced by application of H2O2. Cells were treated with S. oleraceus extracts before or after H2O2 stress. The senescence- associated β-galactosidase (SA-β-gal) activity was used to indicate cell senescence. S....... oleraceus extracts showed higher cellular antioxidant activity than chlorogenic acid in WI-38 cells. S. oleraceus extracts suppressed H2O2 stress-induced premature senescence in a concentration-dependent manner. At 5 and 20 mg/mL, S. oleraceus extracts showed better or equivalent effects of reducing stress......Antioxidants protect against damage from free radicals and are believed to slow the ageing process. Previously, we have reported the high antioxidant activity of 70% methanolic Sonchus oleraceus L. (Asteraceae) leaf extracts. We hypothesize that S. oleraceus extracts protect cells against H2O2...
FENG, CHUNSHENG; LUO, TIANFEI; ZHANG, SHUYAN; LIU, KAI; ZHANG, YANHONG; LUO, YINAN; GE, PENGFEI
Oxidative stress, which is characterized by excessive production of reactive oxygen species (ROS), is a common pathway that results in neuronal injury or death due to various types of pathological stress. Although lycopene has been identified as a potent antioxidant, its effect on hydrogen peroxide (H2O2)-induced neuronal damage remains unclear. In the present study, pretreatment with lycopene was observed to protect SH-SY5Y neuroblastoma cells against H2O2-induced death via inhibition of apoptosis resulting from activation of caspase-3 and translocation of apoptosis inducing factor (AIF) to the nucleus. Furthermore, the over-produced ROS, as well as the reduced activities of anti-oxidative enzymes, superoxide dismutase and catalase, were demonstrated to be alleviated by lycopene. Additionally, lycopene counteracted H2O2-induced mitochondrial dysfunction, which was evidenced by suppression of mitochondrial permeability transition pore opening, attenuation of the decline of the mitochondrial membrane potential, and inhibition of the increase of Bax and decrease of Bcl-2 levels within the mitochondria. The release of cytochrome c and AIF from the mitochondria was also reduced. These results indicate that lycopene is a potent neuroprotectant against apoptosis, oxidative stress and mitochondrial dysfunction, and could be administered to prevent neuronal injury or death. PMID:27035331
Ji Sook Kang
Full Text Available ABSTRACT The fruit of the Prunus mume (Siebold Siebold & Zucc., Rosaceae (Korean name: Maesil has long been used as a health food or valuable medicinal material in traditional herb medicine in Southeast Asian countries. In this study, we determined the potential therapeutic efficacy of the ethanol extract of P. mume fruits (EEPM against H2O2-induced oxidative stress and apoptosis in the murine skeletal muscle myoblast cell line C2C12, and sought to understand the associated molecular mechanisms. The results indicated that exposure of C2C12 cells to H2O2 caused a reduction in cell viability by increasing the generation of intracellular reactive oxygen species and by disrupting mitochondrial membrane permeability, leading to DNA damage and apoptosis. However, pretreatment of the cells with EEPM before H2O2 exposure effectively attenuated these changes, suggesting that EEPM prevented H2O2-induced mitochondria-dependent apoptosis. Furthermore, the increased ex-pression and phosphorylation of nuclear factor erythroid 2-related factor 2 (Nrf2 and up-regulation of heme oxygenase-1 (HO-1, a phase II antioxidant enzyme, were detected in EEPM-treated C2C12 cells. We also found that zinc protoporphyrin IX, an HO-1 inhibitor, attenuated the protective effects of EEPM against H2O2-induced reactive oxygen species accumulation and cytotoxicity. Therefore, these results indicate that the activation of the Nrf2/HO-1 pathway might be involved in the protection of EEPM against H2O2-induced cellular oxidative damage. In conclusion, these results show that EEPM contributes to the prevention of oxidative damage and could be used as a nutritional agent for oxidative stress-related diseases.
Jeung, In Cheul; Jee, Donghyun; Rho, Chang-Rae; Kang, Seungbum
We evaluated the protective effect of ALS-L1023, an extract of Melissa officinalis L. (Labiatae; lemon balm) against oxidative stress-induced apoptosis in human retinal pigment epithelial cells (ARPE-19 cells). ARPE-19 cells were incubated with ALS-L1023 for 24 h and then treated with hydrogen peroxide (H2O2). Oxidative stress-induced apoptosis and intracellular generation of reactive oxygen species (ROS) were assessed by flow cytometry. Caspase-3/7 activation and cleaved poly ADP-ribose polymerase (PARP) were measured to investigate the protective role of ALS-L1023 against apoptosis. The protective effect of ALS-L1023 against oxidative stress through activation of the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) was evaluated by Western blot analysis. ALS-L1023 clearly reduced H2O2-induced cell apoptosis and intracellular production of ROS. H2O2-induced oxidative stress increased caspase-3/7 activity and apoptotic PARP cleavage, which were significantly inhibited by ALS-L1023. Activation of the PI3K/Akt pathway was associated with the protective effect of ALS-L1023 on ARPE-19 cells. ALS-L1023 protected human RPE cells against oxidative damage. This suggests that ALS-L1023 has therapeutic potential for the prevention of dry age-related macular degeneration.
Li, Dan-Dan; Zhong, Bin-Wu; Zhang, Hai-Xia; Zhou, Hong-Yan; Luo, Jie; Liu, Yang; Xu, Gui-Chun; Luan, Chun-Sheng; Fang, Jun
The degeneration of retinal pigment epithelium (RPE) cells in the sub retinal pigment epithelial space and choroid is an initial pathological characteristic for the age-related macular degeneration which is the leading cause of severe vision loss in old people. Moreover, oxidative stress is implicated as a major inducer of RPE cell death. Here, we assessed the correlation between the H2O2-induced RPE cell death and glutamine metabolism. We found under low glutamine supply (20 %), the ARPE-19 cells were more susceptive to H2O2-induced apoptosis. Moreover, the glutamine uptake and the glutaminase (GLS) were suppressed by H2O2 treatments. Moreover, we observed miR-23a was upregulated by H2O2 treatments and overexpression of miR-23a significantly sensitized ARPE-19 cells to H2O2. Importantly, Western blotting and luciferase assay demonstrated GLS1 is a direct target of miR-23a in RPE cells. Inhibition of the H2O2-induced miR-23a by antagomiR protected the RPE cells from the oxidative stress-induced cell death. In addition, recovery of GLS1 expression in miR-23a overexpressed RPE cells rescued the H2O2-induced cell death. This study illustrated a mechanism for the protection of the oxidative-induced RPE cell death through the recovery of glutamine metabolism by inhibition of miR-23a, contributing to the discovery of novel targets and the developments of therapeutic strategies for the prevention of RPE cells from oxidative stress.
Farombi, E.O.; Moller, P.; Dragsted, L.O.
at concentrations between 30-90 mumol/L and decreased H2O2-induced DNA strand breaks and oxidized bases. Neither alpha-tocopherol nor curcumin decreased H2O2-induced DNA damage in this assay. In lymphocytes incubated with Fe3+ /GSH, Fe3+ was reduced to Fe2+ by GSH initiating a free radical generating reaction which...
Ferlazzo, Nadia; Visalli, Giuseppa; Smeriglio, Antonella; Cirmi, Santa; Lombardo, Giovanni Enrico; Campiglia, Pietro; Di Pietro, Angela; Navarra, Michele
It has been reported that oxidant/antioxidant imbalance triggers cell damage that in turn causes a number of lung diseases. Flavonoids are known for their health benefits, and Citrus fruits juices are one of the main food sources of these secondary plant metabolites. The present study was designed to evaluate the effect of the flavonoid fraction of bergamot and orange juices, on H2O2-induced oxidative stress in human lung epithelial A549 cells. First we tested the antioxidant properties of bo...
Ding, Guoliang; Zhao, Jianquan; Jiang, Dianming
Osteoporosis is a disease of the skeleton that is characterized by the loss of bone mass and degeneration of bone microstructure, resulting in an increased risk of fracture. Oxidative stress, which is known to promote oxidative damage to mitochondrial function and also cell apoptosis, has been recently indicated to be implicated in osteoporosis. However, there are few agents that counteract oxidative stress in osteoporosis. In the present study, the protective effects of allicin against the oxidative stress-induced mitochondrial dysfunction and apoptosis were investigated in murine osteoblast-like MC3T3-E1 cells. The results demonstrated that allicin counteracted the reduction of cell viability and induction of apoptosis caused by hydrogen peroxide (H 2 O 2 ) exposure. The inhibition of apoptosis by allicin was confirmed by the inhibition of H 2 O 2 -induced cytochrome c release and caspase-3 activation. Moreover, the inhibition of apoptosis by allicin was identified to be associated with the counteraction of H 2 O 2 -induced mitochondrial dysfunction. In addition, allicin was demonstrated to be able to significantly ameliorate the repressed phosphoinositide 3-kinase (PI3K)/AKT and cyclic adenosine monophosphate response element-binding protein (CREB)/extracellular-signal-regulated kinase (ERK) signaling pathways by H 2 O 2 , which may also be associated with the anti-oxidative stress effects of allicin. In conclusion, allicin protects osteoblasts from H 2 O 2 -induced oxidative stress and apoptosis in MC3T3-E1 cells by improving mitochondrial function and the activation of PI3K/AKT and CREB/ERK signaling. The present study implies a promising role of allicin in oxidative stress-associated osteoporosis.
Diao, Hongying; Liu, Bin; Shi, Yongfeng; Song, Chunli; Guo, Ziyuan; Liu, Ning; Song, Xianjing; Lu, Yang; Lin, Xiaoye; Li, Zhuoran
Oxidative stress-induced myocardial apoptosis and necrosis are involved in ischemia/reperfusion (I/R) injury. This study was performed to investigate microRNA (miR)-210's role in oxidative stress-related myocardial damage. The expression of miR-210 was upregulated in myocardial tissues of I/R rats, while that of Bcl-2 adenovirus E1B 19kDa-interacting protein 3 (BNIP3) was downregulated. To simulate in vivo oxidative stress, H9c2 cells were treated with H2O2 for 48 h. MiR-210 level was increased upon H2O2 stimulation, peaked at 8 h, and then decreased. An opposite expression pattern of BNIP3 was observed. BNIP3 was demonstrated as a direct target of miR-210 via luciferase reporter assay. H2O2-induced cell apoptosis was attenuated by miR-210 mimics, whereas aggravated by miR-210 inhibitor. MiR-210 knockdown-induced cell apoptosis in presence of H2O2 was attenuated by BNIP3 siRNA. Our work demonstrates that miR-210 plays a protective role in H2O2-induced cardiomyocyte apoptosis at least by regulating the pro-apoptotic BNIP3.
Yuan, Xiao-Hua; Fan, Yang-Yang; Yang, Chun-Rong; Gao, Xiao-Rui; Zhang, Li-Li; Hu, Ying; Wang, Ya-Qin; Jun, Hu
The role of progesterone on the cardiovascular system is controversial. Our present research is to specify the effect of progesterone on arterial endothelial cells in response to oxidative stress. Our result showed that H2O2 (150 μM and 300 μM) induced cellular antioxidant response. Glutathione (GSH) production and the activity of Glutathione peroxidase (GPx) were increased in H2O2-treated group. The expression of glutamate cysteine ligase catalytic subunit (GCLC) and modifier subunit (GCLM) was induced in response to H2O2. However, progesterone absolutely abolished the antioxidant response through increasing ROS level, inhibiting the activity of Glutathione peroxidase (GPx), decreasing GSH level and reducing expression of GClC and GCLM. In our study, H2O2 induced nitrogen monoxide (NO) production and endothelial nitric oxide synthase (eNOS) expression, and progesterone promoted H2O2-induced NO production. Progesterone increased H2O2-induced expression of hypoxia inducible factor-α (HIFα) which in turn regulated eNOS expression and NO synthesis. Further study demonstrated that progesterone increased H2O2 concentration of culture medium which may contribute to NO synthesis. Exogenous GSH decreased the content of H2O2 of culture medium pretreated by progesterone combined with H2O2 or progesterone alone. GSH also inhibited expression of HIFα and eNOS, and abolished NO synthesis. Collectively, our study demonstrated for the first time that progesterone inhibited cellular antioxidant effect and increased oxidative stress, promoted NO production of arterial endothelial cells, which may be due to the increasing H2O2 concentration and amplified oxidative stress signal. Copyright © 2015. Published by Elsevier Ltd.
Ben Khedir, S; Moalla, D; Jardak, N; Mzid, M; Sahnoun, Z; Rebai, T
We investigated the efficacy of Pistacia lentiscus fruit oil (PLFO) for protecting human skin from damage due to oxidative stress. PLFO contains natural antioxidants including polyphenols, sterols and tocopherols. We compared the antioxidant potential of PLFO with extra virgin olive oil (EVOO). Explants of healthy adult human skin were grown in culture with either PLFO or EVOO before adding hydrogen peroxide (H2O2). We also used cultured skin explants to investigate the effects of PLFO on lipid oxidation and depletion of endogenous antioxidant defense enzymes including glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) one day after 2 h exposure to H2O2. We found that PLFO scavenged radicals and protected skin against oxidative injury. PLFO exhibited greater antioxidant and free radical scavenging activity than EVOO. Skin explants treated with PLFO inhibited H2O2 induced MDA formation by inhibition of lipid oxidation. In addition, the oil inhibited H2O2 induced depletion of antioxidant defense enzymes including GPx, SOD and CAT. We found that treatment with PLFO repaired skin damage owing to its antioxidant properties.
Straadt, Ida K; Young, Jette F; Petersen, Bent O
In this study, stress in relation to slaughter was investigated in a model system by the use of (13)C, (1)H, and (31)P nuclear magnetic resonance (NMR) spectroscopy for elucidating changes in the metabolites in C2C12 myotubes exposed to H(2)O(2)-induced stress. Oxidative stress resulted in lower...... levels of several metabolites, mainly amino acids; however, higher levels of alanine were apparent in the (13)C spectra after incubation with [(13)C(1)]glucose. In the (13)C spectra [(13)C(3)]lactate tended to increase after exposure to increasing concentrations of H(2)O(2); conversely, a tendency...
Park, Woo Hyun
Exogenous hydrogen peroxide (H2O2) induces oxidative stress and apoptosis in cancer cells. This study evaluated the antiapoptotic effects of pan-caspase and caspase-3, -8, or -9 inhibitors on H2O2-treated Calu-6 and A549 lung cancer cells in relation to reactive oxygen species (ROS) and glutathione (GSH). Treatment with 50-500 μM H2O2 inhibited the growth of Calu-6 and A549 cells at 24 h and induced apoptosis in these cells. All the tested caspase inhibitors significantly prevented cell death in H2O2-treated lung cancer cells. H2O2 increased intracellular ROS levels, including that of O 2·- , at 1 and 24 h. It also increased the activity of catalase but decreased the activity of SOD. In addition, H2O2 triggered GSH deletion in Calu-6 and A549 cells at 24 h. It reduced GSH levels in Calu-6 cells at 1 h but increased them at 24 h. Caspase inhibitors decreased O 2·- levels in H2O2-treated Calu-6 cells at 1 h and these inhibitors decreased ROS levels, including that of O 2·- , in H2O2-treated A549 cells at 24 h. Caspase inhibitors partially attenuated GSH depletion in H2O2-treated A549 cells and increased GSH levels in these cells at 24 h. However, the inhibitors did not affect GSH deletion and levels in Calu-6 cells at 24 h. In conclusion, H2O2 induced caspase-dependent apoptosis in Calu-6 and A549 cells, which was accompanied by increases in ROS and GSH depletion. The antiapoptotic effects of caspase inhibitors were somewhat related to the suppression of H2O2-induced oxidative stress and GSH depletion.
Full Text Available Background: Hypoxic stress is a crucial factor for retaining the cell survival in injured tissue. Overcoming this issue is the key for successful cellular regenerative therapy. Therefore the purpose of this study was to investigate whether the in-vitro pretreatment of Whartonʼs Jelly (WJ derived Mesenchymal stem cells (WJ-MSCs with an antioxidant, namely N-acetylcysteine (NAC, can improve the efficacy of WJ-MSCs for transplantation purpose. Methods: WJ-MSCs were cultured with or without NAC at different concentrations (0.1mM, 1mM and 10mM. To simulate oxidative stress conditions, cultures were exposed to hydrogen peroxide (H2O2 100 µM for 1 hour. Cytoprotective effect of NAC was evaluated by determining cell injury, viability, and proliferation. The oxidative stress is assessed by measuring the activity of glutathione (GSH, superoxide dismutase (SOD, catalase (CAT, and malodialdehyde (MDA. Results: Pretreatment of WJ-MSCs with NAC increased their viability and proliferation in concentration-dependent manner. Furthermore, 10 mM NAC significantly reduced the H2O2 induced oxidative stress by enhancing the activity of GSH, SOD, and CAT and reduced the level of MDA Conclusion: The study results indicate that NAC may abrogate H2O2 induced oxidative-stress of WJ-MSCs. This study provides basis to explore NAC effect on WJ-MSCs survival without cytotoxicity.
Full Text Available Achillolide A is a natural sesquiterpene lactone that we have previously shown can inhibit microglial activation. In this study we present evidence for its beneficial effects on astrocytes under oxidative stress, a situation relevant to neurodegenerative diseases and brain injuries. Viability of brain astrocytes (primary cultures was determined by lactate dehydrogenase (LDH activity, intracellular ROS levels were detected using 2′,7′-dichlorofluorescein diacetate, in vitro antioxidant activity was measured by differential pulse voltammetry, and protein phosphorylation was determined using specific ELISA kits. We have found that achillolide A prevented the H2O2-induced death of astrocytes, and attenuated the induced intracellular accumulation of reactive oxygen species (ROS. These activities could be attributed to the inhibition of the H2O2-induced phosphorylation of MAP/ERK kinase 1 (MEK1 and p44/42 mitogen-activated protein kinases (MAPK, and to the antioxidant activity of achillolide A, but not to H2O2 scavenging. This is the first study that demonstrates its protective effects on brain astrocytes, and its ability to interfere with MAPK activation. We propose that achillolide A deserves further evaluation for its potential to be developed as a drug for the prevention/treatment of neurodegenerative diseases and brain injuries where oxidative stress is part of the pathophysiology.
Rahim, Saleh M; Taha, Ekhlass M; Mubark, Zaid M; Aziz, Salam S; Simon, K D; Mazlan, A G
Cymbopogon citratus (C. citratus) has antioxidant, anti-inflammatory, and chemoprotective properties. This study was conducted to evaluate the protective effect of C. citratus aqueous extract against hydrogen peroxide (H2O2)-induced oxidative stress and injury in the reproductive system of male rats. The twenty-five rats used in this study were divided into five groups, comprised of five rats each. The control group received standard food and drink. The H2O2 group received standard food and water with 0.5% H2O2. The rats in the H2O2 + C. citratus group and H2O2 + vitamin E group received standard food, H2O2, and C. citratus [100 mg·kg(-1) body weight (bw)], or vitamin E as an antioxidant reference (500 mg·kg(-1) bw), respectively. The C. citratus group was given C. citratus (100 mg·kg(-1) bw) in addition to the standard food and drink. The treatments were administered for 30 days. The H2O2 treatment significantly (P citratus, vitamin E, and H2O2 treatment significantly (P citratus aqueous extract reduced oxidative stress and protected male rats against H2O2-induced reproductive system injury.
Full Text Available Pancreatic beta-cell death is known to be the cause of deficient insulin production in diabetes mellitus. Oxidative stress is one of the major causes of beta-cell death. In this study, we investigated the effects of Psoralea corylifolia L. seed (PCS extract on beta-cell death. Oral administration of PCS extract resulted in a significant improvement of hyperglycemia in streptozotocin-induced diabetic mice. PCS extract treatment improved glucose tolerance and increased serum insulin levels. To study the mechanisms involved, we investigated the effects of PCS extract on H2O2-induced apoptosis in INS-1 cells. Treatment with PCS extract inhibited cell death. PCS extract treatment decreased reactive oxygen species level and activated antioxidative enzymes. Among the major components of PCS extract, psoralen and isopsoralen (coumarins, but not bakuchiol, showed preventive effects against H2O2-induced beta-cell death. These findings indicate that PCS extract may be a potential pharmacological agent to protect against pancreatic beta-cell damage caused by oxidative stress associated with diabetes.
Dai, Panpan; Mao, Yixin; Sun, Xiaoyu; Li, Xumin; Muhammad, Ibrahim; Gu, Weiyan; Zhang, Dafeng; Zhou, Yu; Ma, Jianfeng; Ni, Zhenyu; Huang, Shengbin
Osteoblast apoptosis induced by oxidative stress plays a crucial role in the development and progression of osteoporosis. Curcumin, a natural antioxidant isolated from Curcuma longa, has highly protective effects against osteoporosis. However, the effects of curcumin on oxidative stress-induced osteoblast apoptosis remain unclear. This study aimed to explore the effect of curcumin on hydrogen peroxide (H2O2) induced osteoblast apoptosis and the underlying mechanisms. An osteoblastic cell line (Saos-2) was exposed to various concentrations of H2O2 with or without curcumin treatment. Cell viability was evaluated by MTT assays. The apoptosis rate was analyzed by flow cytometry and TUNEL assays. Mitochondrial ROS and membrane potential were determined using a fluorescence microscope. Mitochondrial respiratory enzyme activity was measured using a spectrophotometer. Protein levels were detected by western blotting. Curcumin was cytoprotective because it greatly improved the viability of Saos-2 cells exposed to H2O2 and attenuated H2O2-induced apoptosis. Curcumin treatment also preserved the mitochondrial redox potential, decreased the mitochondrial oxidative status, and improved the mitochondrial membrane potential and functions. Furthermore, curcumin treatment markedly increased levels of phosphorylated protein kinase B (Akt) and phosphorylated glycogen synthase kinase-3β (GSK3β). Curcumin administration ameliorates oxidative stress-induced apoptosis in osteoblasts by preserving mitochondrial functions and activation of Akt-GSK3β signaling. These data provide experimental evidence supporting the clinical use of curcumin for prevention or treatment of osteoporosis. © 2017 The Author(s)Published by S. Karger AG, Basel.
Full Text Available Thymosin beta-4 (Tβ4 is a ubiquitous protein with many properties relating to cell proliferation and differentiation that promotes wound healing and modulates inflammatory mediators. The mechanism by which Tβ4 modulates cardiac protection under oxidative stress is not known. The purpose of this study is to dissect the cardioprotective mechanism of Tβ4 on H(2O(2 induced cardiac damage.Rat neonatal cardiomyocytes with or without Tβ4 pretreatment were exposed to H(2O(2 and expression of antioxidant, apoptotic, and anti-inflammatory genes was evaluated by quantitative real-time PCR and western blotting. ROS levels were estimated by DCF-DA using fluorescent microscopy and fluorimetry. Selected antioxidant, anti-inflammatory and antiapoptotic genes were silenced by siRNA transfections in neonatal cardiomyocytes and effect of Tβ4 on H(2O(2-induced cardiac damage was evaluated.Pre-treatment of Tβ4 resulted in reduction of the intracellular ROS levels induced by H(2O(2 in cardiomyocytes. Tβ4 pretreatment also resulted in an increase in the expression of antiapoptotic proteins and reduction of Bax/BCl(2 ratio in the cardiomyocytes. Pretreatment with Tβ4 resulted in stimulating the expression of antioxidant enzymes copper/zinc SOD and catalase in cardiomyocytes at both transcription and translation levels. Tβ4 treatment resulted in the increased expression of anti-apoptotic and anti-inflammatory genes. Silencing of Cu/Zn SOD and catalase gene resulted in apoptotic cell death in the cardiomyocytes which was prevented by treatment with Tβ4.This is the first report that demonstrates the effect of Tβ4 on cardiomyocytes and its capability to selectively upregulate anti-oxidative enzymes, anti-inflammatory genes, and antiapoptotic enzymes in the neonatal cardiomyocytes thus preventing cell death thereby protecting the myocardium. Tβ4 treatment resulted in decreased oxidative stress and inflammation in the myocardium under oxidative stress.
Ghaffari, Hadi; Ghassam, Behrouz Jalali; Prakash, H S
To investigate capacity of Hyptis suaveolens (H. suaveolens) methanol extract as an antioxidant to protect against carbon tetrachloride (CCl(4))-induced oxidative stress, hepatotoxicity in Albino Wistar rats and cytoprotective effect of hydrogen peroxide (H(2)O(2)) induced cell death in HepG(2) cell line. Two different doses of methanol extract of H. suaveolens were evaluated for the hepatoprotective activity against carbon tetrachloride (CCl(4)) induced hepatotoxicity in rats. Animals in Group I: served as control, group II: H. suaveolens (100 mL/kg b.w), group III: H. suaveolens (50 mL/kg b.w) + CCl(4) (1 mg/kg), group IV: H. suaveolens (100 mL/kg b.w) + CCl(4) (1 mL/kg) and group V: CCl(4) (1 mL/kg). Histopathologic changes of liver were also evaluated. Cytotoxicity was also determined by 3, (4,5-dimethylthiazol-2-yl)2,5-diphenyl-tetrazolium bromide (MTT) assay. Oral sigle dose treatment of CCl(4) produced a marked elevation in the serum levels of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and Lactate dehydrogenase (LDH). Histopathological analysis of the liver of CCl(4)-induced rats revealed marked liver cell necrosis with inflammatory collections that were conformed to increase in the levels of SOD, GSH, GST, GR and LPO. Treatment with H(2)O(2) significantly induced death of HepG(2) cell. Pretreatment with H. suaveolens methanol extract inhibited or attenuated H(2)O(2) induced cytotoxicity. This study shows that H. suaveolens methanol extract can be proposed to protect the liver against CCl(4)-induced oxidative damage in rats and protect the cells against H(2)O(2)-induced oxidative damage in HepG(2) cells. The hepatoprotective and cytoprotective effects might be correlated with its antioxidant and free radical scavenger effects. Copyright © 2012 Hainan Medical College. Published by Elsevier B.V. All rights reserved.
Bayliak, Maria M; Lushchak, Volodymyr I
The effect of aqueous extract from R. rosea root on lifespan and the activity of antioxidant enzymes in budding yeast Saccharomyces cerevisiae have been studied. The supplementation of the growth medium with R. rosea extract decreased survival of exponentially growing S. cerevisiae cells under H(2)O(2)-induced oxidative stress, but increased viability and reproduction success of yeast cells in stationary phase. The extract did not significantly affect catalase activity and decreased SOD activity in chronologically aged yeast population. These results suggest that R. rosea acts as a stressor for S. cerevisiae cells, what sensitizes yeast cells to oxidative stress at exponential phase, but induces adaptation in stationary phase cells demonstrating the positive effect on yeast survival without activation of major antioxidant enzymes. Copyright Â© 2011 Elsevier GmbH. All rights reserved.
Full Text Available Muhamad Noor Alfarizal Kamarudin, Nur Afiqah Mohd Raflee, Sharifah Salwa Syed Hussein, Jia Ye Lo, Hadi Supriady, Habsah Abdul KadirInstitute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, MalaysiaAbstract: Alpha-lipoic acid, a potent antioxidant with multifarious pharmacological benefits has been reported to be neuroprotective in several neuronal models and used to treat neurological disorders such as Alzheimer’s disease. Nonetheless, conclusive mechanisms of alpha-lipoic acid for its protective effects particularly in NG108-15 cells have never been investigated. In this study, the intricate neuroprotective molecular mechanisms by (R-(+-alpha-lipoic acid (R-LA against H2O2-induced cell death in an in vitro model of neurodegeneration were elucidated. Pretreatment with R-LA (2 hours significantly increased NG108-15 cell viability as compared to H2O2-treated cells and mitigated the induction of apoptosis as evidenced by Hoechst 33342/propidium iodide staining. R-LA (12.5–50 µM aggrandized the reduced glutathione over glutathione disulfide ratio followed by a reduction in the intracellular reactive oxygen species level and an increase in mitochondrial membrane potential following H2O2 exposure. Moreover, pretreatment with R-LA stimulated the activation of PI3K-Akt through mTORC1 and mTORC2 components (mTOR, rictor and raptor and production of antiinflammatory cytokine, IL-10 which led to the inactivation of glycogen synthase kinase-3β (GSK-3β and reduction of both Bax/Bcl2 and Bax/Bcl-xL ratios, accompanied by inhibition of the cleaved caspase-3. Additionally, this observation was preceded by the suppression of NF-κβ p65 translocation and production of proinflammatory cytokines (IL-6 and TNF-α. The current findings accentuate new mechanistic insight of R-LA against apoptogenic and brain inflammatory factors in a neuronal model. These results further advocate the therapeutic potential of R-LA for
Full Text Available Oxidative stress-induced retinal pigment epithelial (RPE cell damage is involved in the progression of diabetic retinopathy. Arginine methylation catalyzed by protein arginine methyltransferases (PRMTs has emerged as an important histone modification involved in diverse diseases. Sirtuin (SIRT1 is a protein deacetylase implicated in the onset of metabolic diseases. Therefore, we examined the roles of type I PRMTs and their relationship with SIRT1 in human RPE cells under H2O2-induced oxidative stress. H2O2 treatment increased PRMT1 and PRMT4 expression but decreased SIRT1 expression. Similar to H2O2 treatment, PRMT1 or PRMT4 overexpression increased RPE cell damage. Moreover, the H2O2-induced RPE cell damage was attenuated by PRMT1 or PRMT4 knockdown and SIRT1 overexpression. In this study, we revealed that SIRT1 expression was regulated by PRMT1 but not by PRMT4. Finally, we found that PRMT1 and PRMT4 expression is increased in the RPE layer of streptozotocin-treated rats. Taken together, we demonstrated that oxidative stress induces apoptosis both via PRMT1 in a SIRT1-dependent manner and via PRMT4 in a SIRT1-independent manner. The inhibition of the expression of type I PRMTs, especially PRMT1 and PRMT4, and increased SIRT1 could be therapeutic approaches for diabetic retinopathy.
Wu, Yi; Zhang, Xueqing; Kang, Xueling; Li, Ning; Wang, Rong; Hu, Tiantian; Xiang, Meng; Wang, Xinhong; Yuan, Wenjun; Chen, Alex; Meng, Dan; Chen, Sifeng
Oxidative stress caused by cellular accumulation of reactive oxygen species (ROS) is a major contributor to disease and cell death. However, how induced pluripotent stem cells (iPSC) respond to different levels of oxidative stress is largely unknown. Here, we investigated the effect of H2 O2 -induced oxidative stress on iPSC function in vitro. Mouse iPSC were treated with H2 O2 (25-100 μmol/L). IPSC adhesion, migration, viability, apoptosis and senescence were analysed. Expression of adhesion-related genes, stress defence genes, and osteoblast- and adipocyte-associated genes were determined by reverse transcription polymerase chain reaction. The present study found that H2 O2 (25-100 μmol/L) decreased iPSC adhesion to matrix proteins and endothelial cells, and downregulated gene expression levels of adhesion-related molecules, such as integrin alpha 7, cadherin 1 and 5, melanoma cell adhesion molecule, vascular cell adhesion molecule 1, and monocyte chemoattractant protein-1. H2 O2 (100 μmol/L) decreased iPSC viability and inhibited the capacity of iPSC migration and transendothelial migration. iPSC were sensitive to H2 O2 -induced G2/M arrest, senescence and apoptosis when exposed to H2 O2 at concentrations above 25 μmol/L. H2 O2 increased the expression of stress defence genes, including catalase, cytochrome B alpha, lactoperoxidase and thioredoxin domain containing 2. H2 O2 upregulated the expression of osteoblast- and adipocyte-associated genes in iPSC during their differentiation; however, short-term H2 O2 -induced oxidative stress did not affect the protein expression of the pluripotency markers, octamer-binding transcription factor 4 and sex-determining region Y-box 2. The present results suggest that iPSC are sensitive to H2 O2 toxicity, and inhibition of oxidative stress might be a strategy for improving their functions. © 2013 Wiley Publishing Asia Pty Ltd.
Eno, Colins O; Zhao, Guoping; Venkatanarayan, Avinashnarayan; Wang, Bing; Flores, Elsa R; Li, Chi
The exact roles of lysosomal membrane permeabilization (LMP) in oxidative stress-triggered apoptosis are not completely understood. Here, we first studied the temporal relation between LMP and mitochondrial outer membrane permeabilization (MOMP) during the initial stage of apoptosis caused by the oxidative stress inducer H2O2. Despite its essential role in mediating apoptosis, the expression of the BH3-only Bcl-2 protein Noxa was dispensable for LMP. In contrast, MOMP was dependent on Noxa expression and occurred downstream of LMP. When lysosomal membranes were stabilized by the iron-chelating agent desferrioxamine, H2O2-induced increase in DNA damage, Noxa expression, and subsequent apoptosis were abolished by the inhibition of LMP. Importantly, LMP-induced Noxa expression increase was mediated by p53 and seems to be a unique feature of apoptosis caused by oxidative stress. Finally, exogenous iron loading recapitulated the effects of H2O2 on the expression of BH3-only Bcl-2 proteins. Overall, these data reveal a Noxa-mediated signaling pathway that couples LMP with MOMP and ultimate apoptosis during oxidative stress. Copyright © 2013 Elsevier Inc. All rights reserved.
Wang, Mingxing; Kanako, Nakajima; Zhang, Yanqiu; Xiao, Xulang; Gao, Qipin; Tetsuya, Konishi
Hericium erinaceus (HE) has been used both as a traditional Chinese medicine and home remedy for treatment of gastric and duodenal ulcers and gastritis. EP-1, a purified polysaccharide isolated from HE mycelium, has recently been identified as the active component responsible for HE anti-gastritis activity. Because oxidative stress has been implicated as a pathogenic cause of gastritis and gastric ulcers, EP-1 antioxidant properties were systematically examined in vitro using the human gastric mucosal epithelial cell line, GES-1. Results showed that EP-1 possessed higher oxygen radical absorbance capacity (ORAC) and 2-3 times higher ability to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide and hydroxyl radicals than a hot water extract of commercially available HE fruiting body. A crude mycelial polysaccharide (CMPS) extract of HE, from which EP-1 was purified, showed slightly stronger radical scavenging activity and ORAC than EP-1, with the exception of DPPH-scavenging activity. Antioxidant activities of these extracts were further studied using hydrogen peroxide (H2O2)-abused GES-1 cells; EP-1 dose-dependently preserved cell viability of abused cells as assessed via MTT assay. Moreover, FACS analysis revealed that EP-1 prevented H2O2-induced apoptotic cell death by inhibiting activation of apoptotic cellular signals within mitochondria-dependent apoptotic pathways. CMPS also prevented H2O2-induced oxidative stress, but to a lesser degree than did EP-1, even though CMPS exhibited comparable or stronger in vitro antioxidant activity than did EP-1.
Zhu, Ying; Zhao, Ke-ke; Tong, Yao; Zhou, Ya-li; Wang, Yi-xiao; Zhao, Pei-quan; Wang, Zhao-yang
Increased oxidative stress, which can lead to the retinal pigment epithelium (RPE) cell death by inducing ATP depletion and DNA repair, is believed to be a prominent pathology in age-related macular degeneration (AMD). In the present study, we showed that and 0.1 mM nicotinamide adenine dinucleotide (NAD+) administration significantly blocked RPE cell death induced by 300 μM H2O2. Further investigation showed that H2O2 resulted in increased intracellular ROS level, activation of PARP-1 and subsequently necrotic death of RPE cells. Exogenous NAD+ administration significantly decreased intracellular and intranuclear ROS levels in H2O2-treated RPE cells. In addition, NAD+ administration to H2O2-treated RPE cells inhibited the activation of PARP-1 and protected the RPE cells against necrotic death. Moreover, exogenous NAD+ administration up-regulated autophagy in the H2O2-treated RPE cells. Inhibition of autophagy by LY294002 blocked the decrease of intracellular and intranuclear ROS level. Besides, inhibition of autophagy by LY294002 abolished the protection of exogenous NAD+ against H2O2-induced cell necrotic death. Taken together, our findings indicate that that exogenous NAD+ administration suppresses H2O2-induced oxidative stress and protects RPE cells against PARP-1 mediated necrotic death through the up-regulation of autophagy. The results suggest that exogenous NAD+ administration might be potential value for the treatment of AMD. PMID:27240523
Pronsato, Lucía; Milanesi, Lorena
Accumulating evidence indicates that apoptosis is activated in the aged skeletal muscle, contributing to sarcopenia. We have previously demonstrated that testosterone protects against hydrogen peroxide (H2O2)-induced apoptosis in C2C12 muscle cells, at different levels: morphological, physiological, biochemical and molecular. In the present study we observed that H2O2 induces the mitochondrial permeability transition pore (mPTP) opening and exerts p53 activation in a time-dependent way, with a maximum response after 1-2h of treatment. Testosterone treatment, prior to H2O2, reduces not only p53 phosphorylation but also p66Shc expression, activation and its mitochondrial localization, at the same time that it prevents the mPTP opening. Furthermore, testosterone diminishes JNK and PKCβI phosphorylation induced by H2O2 and probably contributing thus, to reduce the activation of p66Shc. Thus, the mPTP opening, p53, JNK and PKCβI activation, as well as p66Shc mRNA increase, induced by oxidative stress, were reduced by testosterone pretreatment. The data presented in this work show some of the components upstream of the classical apoptotic pathway, that are activated during oxidative stress and that are points where testosterone exerts its protective action against apoptosis, exposing some of the puzzle pieces of the intricate network that aged skeletal muscle apoptosis represents. Copyright © 2015. Published by Elsevier Inc.
Zhu, Ying; Zhao, Ke-Ke; Tong, Yao; Zhou, Ya-Li; Wang, Yi-Xiao; Zhao, Pei-Quan; Wang, Zhao-Yang
Increased oxidative stress, which can lead to the retinal pigment epithelium (RPE) cell death by inducing ATP depletion and DNA repair, is believed to be a prominent pathology in age-related macular degeneration (AMD). In the present study, we showed that and 0.1 mM nicotinamide adenine dinucleotide (NAD(+)) administration significantly blocked RPE cell death induced by 300 μM H2O2. Further investigation showed that H2O2 resulted in increased intracellular ROS level, activation of PARP-1 and subsequently necrotic death of RPE cells. Exogenous NAD(+) administration significantly decreased intracellular and intranuclear ROS levels in H2O2-treated RPE cells. In addition, NAD(+) administration to H2O2-treated RPE cells inhibited the activation of PARP-1 and protected the RPE cells against necrotic death. Moreover, exogenous NAD(+) administration up-regulated autophagy in the H2O2-treated RPE cells. Inhibition of autophagy by LY294002 blocked the decrease of intracellular and intranuclear ROS level. Besides, inhibition of autophagy by LY294002 abolished the protection of exogenous NAD(+) against H2O2-induced cell necrotic death. Taken together, our findings indicate that that exogenous NAD(+) administration suppresses H2O2-induced oxidative stress and protects RPE cells against PARP-1 mediated necrotic death through the up-regulation of autophagy. The results suggest that exogenous NAD(+) administration might be potential value for the treatment of AMD.
Shi, Kai; Wang, Xulei; Zhu, Jie; Cao, Guiqun; Zhang, Kang; Su, Zhiguang
Oxidative stress can cause injury in retinal endothelial cells. Salidroside is a strong antioxidative and cytoprotective supplement in Chinese traditional medicine. In this study, we investigated the effects of salidroside on H2O2-induced primary retinal endothelial cells injury. Salidroside decreased H2O2-induced cell death, and efficiently suppressed cellular ROS production, malondialdehyde generation, and cell apoptosis induced by H2O2 treatment. Salidroside induced the intracellular mRNA expression, protein expression, and enzymatic activities of catalase and Mn-SOD and increased the ratio of Bcl2/Bax. Our results demonstrated that salidroside protected retinal endothelial cells against oxidative injury through increasing the Bcl2/Bax signaling pathway and activation of endogenous antioxidant enzymes. This finding presents salidroside as an attractive agent with potential to attenuate retinopathic diseases.
Zheng, Xiang-Tao; Wu, Zi-Heng; Wei, Ye; Dai, Ju-Ji; Yu, Guan-Feng; Yuan, FengLai; Ye, Le-Chi
Vascular endothelial cells are highly sensitive to oxidative stress, and this is one of the mechanisms by which widespread endothelial dysfunction is induced in most cardiovascular diseases and disorders. However, how these cells can survive in oxidative stress environments remains unclear. Salidroside, a traditional Chinese medicine, has been shown to confer vascular protective effects. We aimed to understand the role of autophagy and its regulatory mechanisms by treating human umbilical vein endothelial cells (HUVECs) with salidroside under oxidative stress. HUVECs were treated with salidroside and exposed to hydrogen peroxide (H2O2). The results indicated that salidroside exerted cytoprotective effects in an H2O2-induced HUVEC injury model and suppressed H2O2-induced apoptosis of HUVECs. Pretreatment with 3-methyladenine (3-MA), an autophagy inhibitor, increased oxidative stress-induced HUVEC apoptosis, while the autophagy activator rapamycin induced anti-apoptosis effects in HUVECs. Salidroside increased autophagy and decreased apoptosis of HUVECs in a dose-dependent manner under oxidative stress. Moreover, 3-MA attenuated salidroside-induced HUVEC autophagy and promoted apoptosis, whereas rapamycin had no additional effects compared with salidroside alone. Salidroside upregulated AMPK phosphorylation but downregulated mTOR phosphorylation under oxidative stress; however, administration of compound C, an AMPK inhibitor, abrogated AMPK phosphorylation and increased mTOR phosphorylation and apoptosis compared with salidroside alone. These results suggest that autophagy is a protective mechanism in HUVECs under oxidative stress and that salidroside might promote autophagy through activation of the AMPK pathway and downregulation of mTOR pathway.
Wang, Yan; Liu, Qian; Xu, Yingqiong; Zhang, Yuanyuan; Lv, Yanni; Tan, Yisha; Jiang, Nan; Cao, Guosheng; Ma, Xiaonan; Wang, Jingrong; Cao, Zhengyu; Yu, Boyang; Kou, Junping
Oxidative stress-induced cytoskeletal dysfunction of neurons has been implicated as a crucial cause of cell apoptosis or death in the central nervous system (CNS) diseases, such as neurodegenerative and psychiatric diseases. The application of neuroprotectants rescuing the neurons from cytoskeletal damage and apoptosis can be a potential treatment for these CNS diseases. Ginsenoside Rg1 (Rg1), one of the major active components of ginseng, has been reported possessing notable neuroprotective activities. However, there is rare report about its effect on cytoskeleton and its undergoing mechanism. The current study is to reveal the regulatory effects of Rg1 on cytoskeletal and morphological lesion in oxidative stress-induced neuronal apoptosis. The results demonstrated that pre-treatment with Rg1 (0.1-10 μM) attenuated hydrogen peroxide (H2O2)-induced neuronal apoptosis and oxidative stress through reducing the intracellular reactive oxygen species (ROS) production and methane dicarboxylic aldehyde (MDA) level. The Rg1 treatment also abolished H2O2-induced morphological changes, including cell rounding, membrane blebbing, neurite retraction and nuclei condensation, which were generated by myosin IIA-actin interaction. These effects were mediated via the down-regulation of caspase-3, ROCK1 (Rho-associated kinase1) activation and myosin light chain (MLC, Ser-19) phosphorylation. Furthermore, inhibiting myosin II activity with blebbistatin partly blocked the neuroprotective effects of Rg1. The computer-aided homology modelling revealed that Rg1 preferentially positioned in the actin binding cleft of myosin IIA and might block the binding of myosin IIA to actin filaments. Accordingly, the neuroprotective mechanism of Rg1 is related to the activity that inhibits myosin IIA-actin interaction and the caspase-3/ROCK1/MLC signaling pathway. These findings put some insights into the unique neuroprotective properties of Rg1 associated with the regulation of myosin IIA
Steeves, Craig H; Potrykus, Joanna; Barnett, David A; Bearne, Stephen L
The anaerobic, Gram-negative bacillus Fusobacterium nucleatum plays a vital role in oral biofilm formation and the development of periodontal disease. The organism plays a central bridging role between early and late colonizers within dental plaque and plays a protective role against reactive oxygen species. Using a two-dimensional gel electrophoresis and mass spectrometry approach, we have annotated 78 proteins within the proteome of F. nucleatum subsp. nucleatum and identified those proteins whose apparent intracellular concentrations change in response to either O(2)- or H(2)O(2)-induced oxidative stress. Three major protein systems were altered in response to oxidative stress: (i) proteins of the alkyl hydroperoxide reductase/thioredoxin reductase system were increased in intracellular concentration; (ii) glycolytic enzymes were modified by oxidation (i.e. D-glyceraldehyde 3-phosphate dehydrogenase, and fructose 6-phosphate aldolase) or increased in intracellular concentration, with an accompanying decrease in ATP production; and (iii) the intracellular concentrations of molecular chaperone proteins and related proteins (i.e. ClpB, DnaK, HtpG, and HrcA) were increased. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Zhang, Zhanquan; Chen, Jian; Li, Boqiang; He, Chang; Chen, Yong; Tian, Shiping
The limitations of chemical fungicides for the control of postharvest diseases have recently become more apparent. The utilization of antagonistic microorganisms is a promising alternative to that of fungicides to control postharvest decay. In previous studies, the antagonistic yeast Cryptococcus laurentii has shown excellent effects of biocontrol and great potential for practical application. Adverse conditions, such as oxidative stress, limit the practical application of antagonistic yeast. In this study, we investigated the oxidative stress tolerance of C. laurentii and the associated mechanisms. The results indicated that exogenous oxidative stress has a significant effect on the viability and biocontrol efficiency of C. laurentii . H 2 O 2 -induced oxidative stress led to the accumulation of reactive oxygen species. The results of flow cytometric analysis suggested that apoptosis is responsible for the reduced survival rate of C. laurentii under oxidative stress. Using tests of antioxidant activity, we found that C. laurentii could employ enzymatic systems to resist exogenous oxidative stress. The addition of exogenous glutathione, a non-enzymatic antioxidant, to the media can significantly enhance oxidative tolerance and biocontrol efficiency of C. laurentii .
Full Text Available Purpose. We aimed to investigate the possible effects of melatonin on gene expressions and activities of MnSOD and catalase under conditions of oxidative stress induced by hydrogen peroxide (H2O2 in peripheral blood mononuclear cells (PBMCs. Materials and Methods. PBMCs were isolated from healthy subjects and treated as follows: (1 control (only with 0.1% DMSO for 12 h; (2 melatonin (1 mM for 12 h; (3 H2O2 (250 μM for 2 h; (4 H2O2 (250 μM for 2 h following 10 h pretreatment with melatonin (1 mM. The gene expression was evaluated by real-time PCR. MnSOD and catalase activities in PBMCs were determined by colorimetric assays. Results. Pretreatment of PBMCs with melatonin significantly augmented expression and activity of MnSOD which were diminished by H2O2. Melatonin treatment of PBMCs caused a significant upregulation of catalase by almost 2-fold in comparison with untreated cells. However, activity and expression of catalase increased by 1.5-fold in PBMCs under H2O2-induced oxidative stress compared with untreated cell. Moreover, pretreatment of PBMCs with melatonin resulted in a significant 1.8-fold increase in catalase expression compared to PBMCs treated only with H2O2. Conclusion. It seems that melatonin could prevent from undesirable impacts of H2O2-induced oxidative stress on MnSOD downregulation. Moreover, melatonin could promote inductive effect of H2O2 on catalase mRNA expression.
Niels A. J. Cremers
Full Text Available Mesenchymal stem cell (MSC administration is a promising adjuvant therapy to treat tissue injury. However, MSC survival after administration is often hampered by oxidative stress at the site of injury. Heme oxygenase (HO generates the cytoprotective effector molecules biliverdin/bilirubin, carbon monoxide (CO and iron/ferritin by breaking down heme. Since HO-activity mediates anti-apoptotic, anti-inflammatory, and anti-oxidative effects, we hypothesized that modulation of the HO-system affects MSC survival. Adipose-derived MSCs (ASCs from wild type (WT and HO-2 knockout (KO mice were isolated and characterized with respect to ASC marker expression. In order to analyze potential modulatory effects of the HO-system on ASC survival, WT and HO-2 KO ASCs were pre-treated with HO-activity modulators, or downstream effector molecules biliverdin, bilirubin, and CO before co-exposure of ASCs to a toxic dose of H2O2. Surprisingly, sensitivity to H2O2-mediated cell death was similar in WT and HO-2 KO ASCs. However, pre-induction of HO-1 expression using curcumin increased ASC survival after H2O2 exposure in both WT and HO-2 KO ASCs. Simultaneous inhibition of HO-activity resulted in loss of curcumin-mediated protection. Co-treatment with glutathione precursor N-Acetylcysteine promoted ASC survival. However, co-incubation with HO-effector molecules bilirubin and biliverdin did not rescue from H2O2-mediated cell death, whereas co-exposure to CO-releasing molecules-2 (CORM-2 significantly increased cell survival, independently from HO-2 expression. Summarizing, our results show that curcumin protects via an HO-1 dependent mechanism against H2O2-mediated apoptosis, and likely through the generation of CO. HO-1 pre-induction or administration of CORMs may thus form an attractive strategy to improve MSC therapy.
Yu, Jing-Song; Leng, Peng-Fei; Li, Yi-Fu; Wang, Yong-Quan; Wang, Yan; An, Rui-Hua; Qi, Ji-Ping
Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that interacts with multiple signaling pathways during prostate development. In the present study, LNCaP cells were knocked down of AhR by siRNA, or treated with the AhR agonist 3-methylcholanthrene (3MC). The effects of AhR on LNCaP cells and the associated mechanisms were studied both under normal condition and under hydrogen peroxide (H 2 O 2 ) - induced oxidative stress. MTT, transwell chamber assays and flow cytometry were employed to investigate cell proliferation, invasion, and apoptosis, respectively, whereas the DNA damage response (DDR) signaling (phosphorylation of ataxia-telangiectasia mutated [ATM], check-point kinase 2 [Chk2], histone H2AX, p53, and cleaved poly-ADP-ribose polymerase [PARP]) was detected by western blotting. Exposure of LNCaP cells to H 2 O 2 inhibited their viability and migration, and induced apoptosis, at a greater extent compared with the culture under normal conditions. In addition, the oxidative stress increased p-ATM, p-Chk2, p-p53, and p-H2AX expression levels significantly. Knockdown of AhR attenuated the aforementioned effects caused by H 2 O 2 -induced oxidative stress. Activation of AhR by 3MC treatment, further aggravated these changes of LNCaP cells on oxidative stress. The findings indicated that AhR suppresses the viability and migration of LNCaP cells notably under oxidative stress, and this process is associated with positive regulation of the responses to oxidative DNA damage.
Pickering, Andrew M; Staab, Trisha A; Tower, John; Sieburth, Derek; Davies, Kelvin J A
In mammalian cells, hydrogen peroxide (H(2)O(2))-induced adaptation to oxidative stress is strongly dependent on an Nrf2 transcription factor-mediated increase in the 20S proteasome. Here, we report that both Caenorhabditis elegans nematode worms and Drosophila melanogaster fruit flies are also capable of adapting to oxidative stress with H(2)O(2) pre-treatment. As in mammalian cells, this adaptive response in worms and flies involves an increase in proteolytic activity and increased expression of the 20S proteasome, but not of the 26S proteasome. We also found that the increase in 20S proteasome expression in both worms and flies, as in mammalian cells, is important for the adaptive response, and that it is mediated by the SKN-1 and CNC-C orthologs of the mammalian Nrf2 transcription factor, respectively. These studies demonstrate that stress mechanisms operative in cell culture also apply in disparate intact organisms across a wide biological diversity.
Our previous study has demonstrated that apo-10’-lycopenoic acid (ALA), an enzymatic metabolite of lycopene, can suppress lung carcinogenesis in an animal model. However, the potential mechanism(s) underlying this protection is not well defined. It has been suggested that lycopene or its hydrophilic...
Zhou, Silei; Han, Quanli; Wang, Ru; Li, Xin; Wang, Qingyang; Wang, Huizhong; Wang, Jing; Ma, Yuanfang
Peroxiredoxin2 (PRDX2) is a member of the peroxiredoxin family of antioxidant enzymes. A number of previous studies have indicated that PRDX2 may serve a cell type-dependent role in tumorigenesis. Recently, PRDX2 has been identified to be the new target of miR-122a, which has been demonstrated to be frequently downregulated in hepatocellular carcinoma (HCC). Thus, PRDX2 may have a pro-tumorigenic role in HCC. Because the role of PRDX2 in HCC has not yet been reported, it is of interest to explore how PRDX2 may affect reactive oxygen species (ROS)-mediated cell death in HCC cells. The present study analyzed the effects of PRDX2 knockdown or overexpression on hydrogen peroxide (H2O2)-induced cell death in HCC SMMC-7721 cells. Tumor necrosis factor-α (TNF-α)-induced cell death upon PRDX2 knockdown or overexpression was also examined in SMMC-7721 cells. It was found that PRDX2 knockdown augmented H2O2-induced cell death in SMMC-7721 cells, whereas PRDX2 overexpression exhibited opposite effects. By contrast, PRDX2 knockdown enhanced TNF-α-induced apoptosis, whereas PRDX2 overexpression reduced it, even though both treatments showed little effects on TNF-α-induced necrosis in SMMC-7721 cells. Further exploration confirmed PRDX2 knockdown led to enhanced ROS generation in response to H2O2. Taken together, the present study supports that PRDX2 serves a pro-tumorigenic role in HCC through, at least partially, limiting ROS-mediated apoptosis under oxidative stress.
Del Bo', Cristian; Porrini, Marisa; Campolo, Jonica; Parolini, Marina; Lanti, Claudia; Klimis-Zacas, Dorothy; Riso, Patrizia
We previously reported that a portion of blueberries reversed endothelial dysfunction induced by acute cigarette smoking. Since smoking-induced endothelial dysfunction is associated with a condition of oxidative stress, we evaluated whether the observed effect was mediated by modulation of markers of oxidative stress and antioxidant defence. Fourteen out of 16 male healthy smokers previously enrolled, participated in a three-armed randomized controlled study with the following experimental conditions: smoking treatment (one cigarette); blueberry treatment (300g of blueberries) + smoking (one cigarette); control treatment (300ml of water with sugar) + smoking (one cigarette). The cigarette was smoked 100min after blueberry/control/water consumption. Each treatment was separated by 1 week of washout period. Plasma vitamin (C, B12 and folate) and aminothiol concentrations, endogenous [formamidopyrimidine-DNA glycosylase (FPG)-sensitive sites] and oxidatively induced DNA damage (resistance to H2O2-induced DNA damage) in peripheral blood mononuclear cells (PBMCs) were measured at baseline and 20, 60, 90, 120min and 24h after smoking. On the whole, analysis of variance did not show a significant effect of treatment on the modulation of markers of oxidative stress and antioxidant defence but revealed an effect of time for plasma concentrations of vitamin C (P = 0.003), B12 (P 0.05) and H2O2-induced DNA damage (P > 0.05) in PBMCs. In conclusion, the consumption of a single blueberry portion failed to modulate markers of oxidative stress and antioxidant defence investigated in our experimental conditions. Further studies are necessary to elucidate this finding and help clarifying the mechanisms of protection of blueberries against smoking-induced endothelial dysfunction. © The Author 2015. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: firstname.lastname@example.org.
Akcakaya, Handan; Dal, Fulya; Tok, Sabiha; Cinar, Suzan-Adin; Nurten, Rustem
Oxidative stress can be defined as the increase of oxidizing agents like reactive oxygen and nitrogen species, or the imbalance between the antioxidative defense mechanism and oxidants. Cell cycle checkpoint response can be defined as the arrest of the cell cycle functioning after damaging chemical exposure. This temporary arrest may be a period of time given to the cells to repair the DNA damage before entering the cycle again and completing mitosis. In order to determine the effects of oxidative stress on several cell cycle phases, human erytroleukemia cell line (K562) was synchronized with mimosine and genistein, and cell cycle analysis carried out. Synchronized cells were exposed to oxidative stress with hydrogen peroxide (H2O2) at several concentrations and different times. Changes on mitochondria membrane potential (ΔΨm) of K562 cells were analyzed in G1, S, and G2 /M using Rhodamine 123 (Rho 123). To determine apoptosis and necrosis, stressed cells were stained with Annexin V (AnnV) and propidium iodide (PI) for flow cytometry. Changes were observed in the ΔΨm of synchronized and asynchronized cells that were exposed to oxidative stress. Synchronized cells in S phase proved resistant to the effects of oxidative stress and synchronized cells at G2 /M phase were sensitive to the effects of H2O2 -induced oxidative stress at 500 μM and above. © 2014 International Federation for Cell Biology.
Full Text Available After sudden traumatic brain injuries, secondary injuries may occur during the following days or weeks, which leads to the accumulation of reactive oxygen species (ROS. Since ROS exacerbate brain damage, it is important to protect neurons against their activity. Zinc finger protein 179 (Znf179 was shown to act as a neuroprotective factor, but the regulation of gene expression under oxidative stress remains unknown. In this study, we demonstrated an increase in Znf179 protein levels in both in vitro model of hydrogen peroxide (H2O2-induced ROS accumulation and animal models of traumatic brain injury. Additionally, we examined the sub-cellular localization of Znf179, and demonstrated that oxidative stress increases Znf179 nuclear shuttling and its interaction with specificity protein 1 (Sp1. Subsequently, the positive autoregulation of Znf179 expression, which is Sp1-dependent, was further demonstrated using luciferase reporter assay and green fluorescent protein (GFP-Znf179-expressing cells and transgenic mice. The upregulation of Sp1 transcriptional activity induced by the treatment with nerve growth factor (NGF led to an increase in Znf179 levels, which further protected cells against H2O2-induced damage. However, Sp1 inhibitor, mithramycin A, was shown to inhibit NGF effects, leading to a decrease in Znf179 expression and lower cellular protection. In conclusion, the results obtained in this study show that Znf179 autoregulation through Sp1-dependent mechanism plays an important role in neuroprotection, and NGF-induced Sp1 signaling may help attenuate more extensive (ROS-induced damage following brain injury.
Full Text Available Restenosis after intraluminal or open vascular reconstruction remains an important clinical problem. Vascular endothelial cell (EC injury induced by oxidative stress plays an important role in the development of intimal hyperplasia. In this study, we sought to evaluate the protective effects of Bcl-xl overexpression in vitro on oxidative stress-induced EC injury and the role of the Akt/endothelial nitric oxide synthase (eNOS pathway. Human umbilical vein endothelial cells (HUVECs exposed to hydrogen peroxide (H2O2, 0.5 mM were used as the experimental oxidative stress model. The Bcl-xl gene was transferred into HUVECs through recombinant adenovirus vector pAdxsi-GFP-Bcl-xl before oxidative treatment. Cell apoptosis was evaluated by Annexin V/propidium iodide and Hoechst staining, caspase-7 and PARP cleavage. Cell viability was assessed using the cell counting kit-8 assay, proliferating cell nuclear antigen (PCNA immunocytochemical detection and the scratching assay. Expressions of Akt, phospho-Akt and eNOS were detected by Western blotting. Our results showed that H2O2 induced apoptosis and decreased the cell viability of HUVECs. Bcl-xl overexpression significantly protected cells from H2O2-induced cell damage and apoptosis and maintained the cell function. Furthermore, the level of phospho-Akt and eNOS protein expression was significantly elevated when pretreated with Bcl-xl gene transferring. These findings suggest that Bcl-xl overexpression exerts an anti-apoptotic and protective effect on EC function. The Akt/eNOS signaling pathway is probably involved in these processes.
Full Text Available The health beneficial effects of dietary polyphenols have been attributed to their intrinsic antioxidant activity, which depends on the structure of the compound and number of hydroxyl groups. In this study, the protective effects of pyrogallol, phloroglucinol, and myricetin on the yeast Saccharomyces cerevisiae were investigated. Pyrogallol and myricetin, which have a pyrogallol structure in the B ring, increased H2O2 resistance associated with a reduction in intracellular oxidation and protein carbonylation, whereas phloroglucinol did not exert protective effects. The acquisition of oxidative stress resistance in cells pretreated with pyrogallol and myricetin was not associated with an induction of endogenous antioxidant defences as assessed by the analysis of superoxide dismutase and catalase activities. However, myricetin, which provided greater stress resistance, prevented H2O2-induced glutathione oxidation. Moreover, myricetin increased the chronological lifespan of yeast lacking the mitochondrial superoxide dismutase (Sod2p, which exhibited a premature aging phenotype and oxidative stress sensitivity. These findings show that the presence of hydroxyl groups in the ortho position of the B ring in pyrogallol and myricetin contributes to the antioxidant protection afforded by these compounds. In addition, myricetin may alleviate aging-induced oxidative stress, particularly when redox homeostasis is compromised due to downregulation of endogenous defences present in mitochondria.
Isolation and quantification of major chlorogenic acids in three major instant coffee brands and their potential effects on H2O2-induced mitochondrial membrane depolarization and apoptosis in PC-12 cells
Coffee is a most consumed drink worldwide. In this paper, from three commercially available instant coffees, major chlorogenic acids were isolated and quantified using HPLC and NMR spectroscopic methods. Also, their anti-oxidant and anti-inflammatory activities were determined using DPPH-radical sca...
Conti, Valeria; Corbi, Graziamaria; Simeon, Vittorio; Russomanno, Giusy; Manzo, Valentina; Ferrara, Nicola; Filippelli, Amelia
Oxidative stress is strongly associated with aging and age-related diseases and plays a crucial role in endothelial dysfunction development. To better understand the molecular mechanisms of aging and stress response in humans, we examined changes to young and older human endothelial cells over time (72, 96 and 120 h), before and after H2O2-induced stress. We measured the expression of the deacetylase Sirtuin 1 (Sirt1) and its transcriptional target Forkhead box O3a (Foxo3a); TBARS, a well-known marker of overall oxidative stress, and catalase activity as index of antioxidation. Moreover, we quantified levels of cellular senescence by senescence-associated β galactosidase (SA-βgal) assay. Under oxidative stress induction older cells showed a progressive decrease of Sirt1 and Foxo3a expression, persistently high TBARS levels with high, but ineffective Cat activity to counteract such levels. In addition cellular senescence drastically increased in older cells compared with Young cells both in presence and in the absence of oxidative stress. By following the cell behavior during the time course, we can hypothesize that while in young cells an oxidative stress induction stimulated an adequate response through activation of molecular factor crucial to counteract oxidative stress, the older cells are not able to adequately adapt themselves to external stress stimuli. During their life, endothelial cells impair the ability to defend themselves from oxidative stress stimuli. This dysfunction involves the pathway of Sirt1 a critical regulator of oxidative stress response and cellular lifespan, underlining its crucial role in endothelial homeostasis control during aging and age-associated diseases.
Full Text Available Previous studies have shown that the JAK2/STAT3 signaling pathway plays a regulatory role in cellular oxidative stress injury (OSI. In this study, we explored the role of the JAK2/STAT3 signaling pathway in hydrogen peroxide (H2O2-induced OSI and the protective effect of melatonin against (H2O2-induced injury in human umbilical vein endothelial cells (HUVECs. AG490 (a specific inhibitor of the JAK2/STAT3 signaling pathway and JAK2 siRNA were used to manipulate JAK2/STAT3 activity, and the results showed that AG490 and JAK2 siRNA inhibited OSI and the levels of p-JAK2 and p-STAT3. HUVECs were then subjected to H2O2 in the absence or presence of melatonin, the main secretory product of the pineal gland. Melatonin conferred a protective effect against H2O2, which was evidenced by improvements in cell viability, adhesive ability and migratory ability, decreases in the apoptotic index and reactive oxygen species (ROS production and several biochemical parameters in HUVECs. Immunofluorescence and Western blotting showed that H2O2 treatment increased the levels of p-JAK2, p-STAT3, Cytochrome c, Bax and Caspase3 and decreased the levels of Bcl2, whereas melatonin treatment partially reversed these effects. We, for the first time, demonstrate that the inhibition of the JAK2/STAT3 signaling pathway results in a protective effect against endothelial OSI. The protective effects of melatonin against OSI, at least partially, depend upon JAK2/STAT3 inhibition.
Kim, Nam-Yi; Ahn, Sang-Gun; Kim, Soo-A
Cinnamaldehyde (CA) has various functional properties, such as anti-cancer, anti-microbial, anti-inflammatory, and anti-oxidant activities. This study examined the intracellular signaling mechanisms of CA on the oxidative stress response in human dental pulp cells (hDPCs). The results showed that CA did not have any cell cytotoxicity or cause morphological changes at concentrations up to 50µM. A CA treatment strongly up-regulated the cellular protein level of heme oxygenase-1 (HO-1) and promoted Nrf2 translocation to the nucleus. CA-mediated Nrf2/HO-1 activation reduced the level of reactive oxygen species and protected the hDPCs from H2O2-induced oxidative stress, which induces apoptosis. Moreover, HO-1 depletion by siRNA attenuated the CA-mediated cell protection against oxidative stress. These results indicate that CA protects hDPCs dysfunction under oxidative stress conditions, and this effect is mediated by Nrf2 activation and the up-regulation of HO-1. Overall, these observations suggest that CA is a potential therapeutic agent for cell protection against oxidative stress. Copyright © 2017 Elsevier B.V. All rights reserved.
Full Text Available Hericium erinaceus (HE has been used both as a traditional Chinese medicine and home remedy for treatment of gastric and duodenal ulcers and gastritis. EP-1, a purified polysaccharide isolated from HE mycelium, has recently been identified as the active component responsible for HE anti-gastritis activity. Because oxidative stress has been implicated as a pathogenic cause of gastritis and gastric ulcers, EP-1 antioxidant properties were systematically examined in vitro using the human gastric mucosal epithelial cell line, GES-1. Results showed that EP-1 possessed higher oxygen radical absorbance capacity (ORAC and 2-3 times higher ability to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH, superoxide and hydroxyl radicals than a hot water extract of commercially available HE fruiting body. A crude mycelial polysaccharide (CMPS extract of HE, from which EP-1 was purified, showed slightly stronger radical scavenging activity and ORAC than EP-1, with the exception of DPPH-scavenging activity. Antioxidant activities of these extracts were further studied using hydrogen peroxide (H2O2-abused GES-1 cells; EP-1 dose-dependently preserved cell viability of abused cells as assessed via MTT assay. Moreover, FACS analysis revealed that EP-1 prevented H2O2-induced apoptotic cell death by inhibiting activation of apoptotic cellular signals within mitochondria-dependent apoptotic pathways. CMPS also prevented H2O2-induced oxidative stress, but to a lesser degree than did EP-1, even though CMPS exhibited comparable or stronger in vitro antioxidant activity than did EP-1.
Full Text Available BACKGROUND: Cell senescence is central to a large body of age related pathology, and accordingly, cardiomyocytes senescence is involved in many age related cardiovascular diseases. In consideration of that, delaying cardiomyocytes senescence is of great importance to control clinical cardiovascular diseases. Previous study indicated that bradykinin (BK protected endothelial cells from senescence induced by oxidative stress. However, the effects of bradykinin on cardiomyocytes senescence remain to be elucidated. In this study, we investigated the effect of bradykinin on H2O2-induced H9C2 cells senescence. METHODS AND RESULTS: Bradykinin pretreatment decreased the senescence induced by H2O2 in cultured H9C2 cells in a dose dependent manner. Interestingly, 1 nmol/L of BK almost completely inhibited the increase in senescent cell number and p21 expression induced by H2O2. Since H2O2 induces senescence through superoxide-induced DNA damage, we also observed the DNA damage by comet assay, and BK markedly reduced DNA damage induced by H2O2, and moreover, BK treatment significantly prevented reactive oxygen species (ROS production in H9C2 cells treated with H2O2. Importantly, when co-incubated with bradykinin B2 receptor antagonist HOE-140 or eNOS inhibitor N-methyl-L-arginine acetate salt (L-NAME, the protective effects of bradykinin on H9C2 senescence were totally blocked. Furthermore, BK administration significantly prevented the increase in nicotinamide adenine dinucleotide phosphate (NADPH oxidase activity characterized by increased ROS generation and gp91 expression and increased translocation of p47 and p67 to the membrane and the decrease in superoxide dismutase (SOD activity and expression induced by H2O2 in H9C2 cells, which was dependent on BK B2 receptor mediated nitric oxide (NO release. CONCLUSIONS: Bradykinin, acting through BK B2 receptor induced NO release, upregulated antioxidant Cu/Zn-SOD and Mn-SOD activity and expression while
Full Text Available The unceasing need for oxygen is in contradiction to the fact that it is in fact toxic to mammals. Namely, its monovalent reduction can have as a consequence the production of short-living, chemically very active free radicals and certain non-radical agents (nitrogen-oxide, superoxide-anion-radicals, hydroxyl radicals, peroxyl radicals, singlet oxygen, peroxynitrite, hydrogen peroxide, hypochlorous acid, and others. There is no doubt that they have numerous positive roles, but when their production is stepped up to such an extent that the organism cannot eliminate them with its antioxidants (superoxide-dismutase, glutathione-peroxidase, catalase, transferrin, ceruloplasmin, reduced glutathion, and others, a series of disorders is developed that are jointly called „oxidative stress.“ The reactive oxygen species which characterize oxidative stress are capable of attacking all main classes of biological macromolecules, actually proteins, DNA and RNA molecules, and in particular lipids. The free radicals influence lipid peroxidation in cellular membranes, oxidative damage to DNA and RNA molecules, the development of genetic mutations, fragmentation, and the altered function of various protein molecules. All of this results in the following consequences: disrupted permeability of cellular membranes, disrupted cellular signalization and ion homeostasis, reduced or loss of function of damaged proteins, and similar. That is why the free radicals that are released during oxidative stress are considered pathogenic agents of numerous diseases and ageing. The type of damage that will occur, and when it will take place, depends on the nature of the free radicals, their site of action and their source. [Projekat Ministarstva nauke Republike Srbije, br. 173034, br. 175061 i br. 31085
Paul, Manoj; Thushara, Ram M; Jagadish, Swamy; Zakai, Uzma I; West, Robert; Kemparaju, Kempaiah; Girish, Kesturu S
Oxidative stress-induced platelet apoptosis is one among the many causes for the development and progression of many disorders like cardiovascular diseases, arthritis, Alzheimer's disease and many chronic inflammatory responses. Many studies have demonstrated the less optimal effect of N-acetyl cysteine (NAC) in oxidative stress-induced cellular damage. This could be due to its less lipophilicity which makes it difficult to enter the cellular membrane. Therefore in the present study, lipophilic sila-amide derivatives (6a and 6b) synthesized through the reaction of NAC with 3-Aminopropyltrimethylsilane and aminomethyltrimethylsilane were used to determine their protective property against oxidative stress-induced platelet apoptosis. At a concentration of 10 µM, compound 6a and 6b were able to significantly inhibit Rotenone/H2O2 induced platelet apoptotic markers like reactive oxygen species, intracellular calcium level, mitochondrial membrane potential, cytochrome c release from mitochondrial to the cytosol, caspase-9 and -3 activity and phosphatidylserine externalization. Therefore, the compounds can be extrapolated as therapeutic agents to protect platelets from oxidative stress-induced platelet apoptosis and its associated complications.
catalase) and apoptotic (AKT, NF-Kβ, ERK1/2, JNK, p53 and p38 MAPK) genes that tended towards survival. Conclusions Taken together, the results of our study showed that the ethyl acetate extract of GBR, with high antioxidant potentials, could prevent H2O2-induced oxidative damage in SH-SY5Y cells. The potential of GBR and its neuroprotective mechanism in ameliorating oxidative stress-related cytotoxicity is therefore worth exploring further. PMID:23866310
Saha, Debarchana; Koli, Swanand; Reddy, Kudumula Venkata Rami
Hemoglobin (Hb), a major protein involved in transport of oxygen (O2 ), is expressed by erythroid lineages. Until recently, it was not known whether non-erythroid cells express Hb. The objective was to evaluate the expression and functional significance of Hb-α and Hb-β in human primary vaginal epithelial cells (hPVECs) and decipher downstream signaling. RT-PCR, qRT-PCR, flow cytometry, Western blot, immunofluorescence were used to evaluate the expression of Hb-α, Hb-β, and nuclear factor E2-related factor-2(Nrf2) after hydrogen peroxide (H2 O2 ) induction. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) assay were used to determine the binding efficiency of Nrf2 on the Hb-α promoter. Stimulation of hPVECs and human vaginal epithelial cell line, VK2/E6E7 with H2 O2 augmented the expression of Hb-α, Hb-β, Nrf2, heme oxygenase-1 (HO-1), and reactive oxygen species (ROS). Treatment of these cells with Nrf2 inhibitor, trigonelline (Trig) inhibited Hb-α and Hb-β expressions. Hb-α and Hb-β overexpression downregulated H2 O2 -induced ROS. The presence of Nrf2 binding domain was demonstrated within Hb-α promoter. The results revealed for the first time that Hb-α and Hb-β were induced by oxidative stress through the activation of Nrf2. Overexpression of Hb-α and Hb-β ameliorated H2 O2 -induced oxidative stress, indicating one of the possible mechanism(s) to protect hPVECS from oxidative stress. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Full Text Available The accumulation of oxidative damage and mitochondrial dysfunction is an important factor that contributes to aging. The Psoralea corylifolia seeds (PCS, commonly known as “Boh-Gol-Zhee” in Korea, have been used traditionally as a medicinal remedy. We investigated whether an extract of PCS has protective effects on oxidative stress and mitochondrial function in hepatocytes. The PCS extract showed an antisenescence effect on human diploid fibroblasts as evidenced by a decreased expression of p16INK4a mRNA and senescence-associated β-galactosidase staining. PCS extract treatment reduced H2O2-induced reactive oxygen species (ROS production in HepG2 cells, inhibited ROS production in hepatocytes of aged mice, and increased superoxide dismutase activity. In H2O2-treated HepG2 cells, PCS extract treatment recovered ATP production. PCS extract treatment recovered the oxygen consumption rate and inhibited reduction of mitochondrial membrane potential induced by oxidative stress, suggesting improvement of mitochondrial function. In addition, PCS extract treatment recovered peroxisome proliferator-activated receptor γ coactivator 1α and carnitine palmitoyltransferase 1 mRNA and protein expression, and inhibited mitochondrial genome damage. Treatment with the major component of PCS extract, bakuchiol, also recovered mitochondrial dysfunction. On the basis of these results, we conclude that PCS extract inhibits ROS production and mitochondrial dysfunction induced by oxidative stress in hepatocytes.
Xu, Xuejing; Li, Dong; Li, Xue; Shi, Qing; Ju, Xiuli
To investigate the impact of miRNA (microRNA) on hepatic oxidative stress damage under the human mesenchymal stem cell conditioned medium (MSC-CM) and explore the roles of the beta-1 adrenergic receptor (ADRB1) and hexokinase 2 (HK2) in this process. Hydrogen peroxide was used to induce oxidative stress injury in the human normal liver cell line L02. MSC-CM was separately prepared. After treatment with MSC-CM, the protective effects of MSC-CM on oxidative stress injury were assessed by changes in apoptosis, cell viability, cell cycle, and mitochondrial membrane potential. According to the microarray analysis, 19 disparately expressed miRNAs were selected for RT-PCR and miR143 identified as having significant differential expression in MSC-CM against oxidative stress injury. Subsequently, the predicted target proteins of miR143 were selected by bioinformatics software, and verified by western blot. In addition, down-regulation and up-regulation of miR143 expression and hydrogen peroxide induced hypoxia injury were carried out on L02 cells to study the role of miR143. MSC-CM significantly attenuated H 2 O 2 induced oxidative stress injury. The expression of miR143 was increased following oxidative stress injury whereas it decreased after MSC-CM treatment. The expression levels of HK2 and ADRB1 regulated by miR143 and Bcl-2 decreased under H 2 O 2 treatment but were restored following MSC-CM treatment. However the expression levels of Bax and BMF increased after H 2 O 2 injury and decreased after MSC-CM treatment. Moreover over-expression or down-regulation of miR143 aggravated or alleviated hepatocyte apoptosis respectively. MSC-CM may alleviate H 2 O 2 induced oxidative stress injury by inhibiting apoptosis and adjusting miRNA expression. Moreover down-regulation of miR143 protects L02 cells from apoptosis and initiates an adaptive process by adjusting the expression of HK2 ADRB1 and apoptosis-related proteins.
Full Text Available p62 is a scaffolding adaptor implicated in the clearance of protein aggregates by autophagy. Reactive oxygen species (ROS can either stimulate or inhibit NFκB-mediated gene expression influencing cellular fate. We studied the effect of hydrogen peroxide (H2O2-mediated oxidative stress and NFκB signaling on p62 expression in the retinal pigment epithelium (RPE and investigated its role in regulation of autophagy and RPE survival against oxidative damage. Cultured human RPE cell line ARPE-19 and primary human adult and fetal RPE cells were exposed to H2O2-induced oxidative stress. The human apolipoprotein E4 targeted-replacement (APOE4 mouse model of AMD was used to study expression of p62 and other autophagy proteins in the retina. p62, NFκB p65 (total, phosphorylated, nuclear and cytoplasmic and ATG10 expression was assessed by mRNA and protein analyses. Cellular ROS and mitochondrial superoxide were measured by CM-H2DCFDA and MitoSOX staining respectively. Mitochondrial viability was determined using MTT activity. qPCR-array system was used to investigate autophagic genes affected by p62. Nuclear and cytoplasmic levels of NFκB p65 were evaluated after cellular fractionation by Western blotting. We report that p62 is up-regulated in RPE cells under H2O2-induced oxidative stress and promotes autophagic activity. Depletion of endogenous p62 reduces autophagy by downregulation of ATG10 rendering RPE more susceptible to oxidative damage. NFκB p65 phosphorylation at Ser-536 was found to be critical for p62 upregulation in response to oxidative stress. Proteasome inhibition by H2O2 causes p62-NFκB signaling as antioxidant pre-treatment reversed p62 expression and p65 phosphorylation when RPE was challenged by H2O2 but not when by Lactacystin. p62 protein but not RNA levels are elevated in APOE4-HFC AMD mouse model, suggesting reduction of autophagic flux in disease conditions. Our findings suggest that p62 is necessary for RPE cytoprotection
Zhang, Jing; Cai, Shuxian; Li, Juan; Xiong, Ligui; Tian, Lili; Liu, Jianjun; Huang, Jianan; Liu, Zhonghua
Oxidative stress can induce neuronal apoptosis via the production of superoxide and hydroxyl radicals. This process is as a major pathogenic mechanism in neurodegenerative disorders. In this study, we aimed to clarify whether theaflavins protect PC12 cells from oxidative stress damage induced by H2O2. A cell model of PC12 cells undergoing oxidative stress was created by exposing cells to 200 μM H2O2 in the presence or absence of varying concentrations of theaflavins (5, 10, and 20 μM). Cell viability was monitored using the MTT assay and Hoechst 33258 staining, showing that 10 μM theaflavins enhanced cell survival following 200 μM H2O2 induced toxicity and increased cell viability by approximately 40 %. Additionally, we measured levels of intracellular reactive oxygen species (ROS) and antioxidant enzyme activity. This suggested that the neuroprotective effect of theaflavins against oxidative stress in PC12 cells is derived from suppression of oxidant enzyme activity. Furthermore, Western blot analyses indicated that theaflavins downregulated the ratio of pro-apoptosis/anti-apoptosis proteins Bax/Bcl-2. Theaflavins also downregulated the expression of caspase-3 compared with a H2O2-treated group that had not been treated with theaflavins. Interestingly, this is the first study to report that the four main components of theaflavins found in black tea can protect neural cells (PC12) from apoptosis induced by H2O2. These findings provide the foundations for a new field of using theaflavins or its source, black tea, in the treatment of neurodegenerative diseases caused by oxidative stress.
Full Text Available Mitochondrial respiratory chain (RC deficits, resulting in augmented mitochondrial ROS (mROS generation, underlie pathogenesis of astrocytes. However, mtDNA-depleted cells (ρ0 lacking RC have been reported to be either sensitive or resistant to apoptosis. In this study, we sought to determine the effects of RC-enhanced mitochondrial stress following oxidative insult. Using noninvasive fluorescence probe-coupled laser scanning imaging microscopy, the ability to resist oxidative stress and levels of mROS formation and mitochondrial calcium (mCa2+ were compared between two different astrocyte cell lines, control and ρ0 astrocytes, over time upon oxidative stress. Our results showed that the cytoplasmic membrane becomes permeated with YO-PRO-1 dye at 150 and 130 minutes in RBA-1 and ρ0 astrocytes, respectively. In contrast to RBA-1, 30 minutes after 20 mM H2O2 exposure, ρ0 astrocytes formed marked plasma membrane blebs, lost the ability to retain Mito-R, and showed condensation of nuclei. Importantly, H2O2-induced ROS and accompanied mCa2+ elevation in control showed higher levels than ρ0 at early time point but vice versa at late time point. Our findings underscore dual phase of RC-defective cells harboring less mitochondrial stress due to low RC activity during short-term oxidative stress but augmented mROS-mediated mCa2+ stress during severe oxidative insult.
Sari, Ece; Tunc-Sarisozen, Yeliz; Mutlu, Hulya; Shahbazi, Reza; Ucar, Gulberk; Ulubayram, Kezban
Targeted delivery of therapeutics is the favourable idea, whereas it is possible to distribute the therapeutically active drug molecule only to the site of action. For this purpose, in this study, catalase encapsulated poly(D,L-lactide-co-glycolide)-block-poly(ethylene glycol) (PLGA-b-PEG) nanoparticles were developed and an endothelial target molecule (anti-ICAM-1) was conjugated to this carrier system in order to decrease the oxidative stress level in the target site. According to the enzymatic activity results, initial catalase activity of nanoparticles was increased from 27.39 U/mg to up to 45.66 U/mg by adding 5 mg/mL bovine serum albumin (BSA). After 4 h, initial catalase activity was preserved up to 46.98% while free catalase retained less than 4% of its activity in proteolytic environment. Furthermore, FITC labelled anti-ICAM-1 targeted catalase encapsulated nanoparticles (anti-ICAM-1/CatNPs) were rapidly taken up by cultured endothelial cells and concomitantly endothelial cells were resistant to H2O2 induced oxidative impairment.
Bhaskaran, Natarajan; Shukla, Sanjeev; Kanwal, Rajnee; Srivastava, Janmejai K; Gupta, Sanjay
Protection of cells from oxidative insult may be possible through direct scavenging of reactive oxygen species, or through stimulation of intracellular antioxidant defense mechanisms by induction of antioxidant gene expression. In this study we investigated the cytoprotective effect of chamomile and elucidated the underlying mechanisms. The cytoprotective effect of chamomile was examined on H(2)O(2)-induced cellular stress in RAW 264.7 murine macrophages. RAW 264.7 murine macrophages treated with chamomile were protected from cell death caused by H(2)O(2). Treatment with 50μM H(2)O(2) for 6h caused significant increase in cellular stress accompanied by cell death in RAW 264.7 macrophages. Pretreatment with chamomile at 10-20μg/mL for 16h followed by H(2)O(2) treatment protected the macrophages against cell death. Chamomile exposure significantly increased the expression of antioxidant enzymes viz. heme oxygenase-1 (HO-1), peroxiredoxin-1 (Prx-1), and thioredoxin-1 (Trx-1) in a dose-dependent manner, compared with their respective controls. Chamomile increased nuclear translocation of Nrf2 with increased phosphorylated Nrf2 levels, and binding to the antioxidant response element in the nucleus. These molecular findings for the first time provide insights into the mechanisms underlying the induction of phase 2 enzymes through the Keap1-Nrf2 signaling pathway by chamomile, and provide evidence that chamomile possesses antioxidant and cytoprotective properties. Copyright © 2012 Elsevier Inc. All rights reserved.
Luís Cláudio Nascimento da Silva
Full Text Available Oxidative stress plays an important role in the induction of cell death and is associated with various pathologic disorders; therefore, the search for natural products that attenuate the effects produced by oxidant agents is greatly increased. Here, the protective effects of native lectin from Cratylia mollis seeds (pCramoll and recombinant Cramoll 1 (rCramoll against H2O2-induced oxidative stress in Vero cells were evaluated. Both lectins significantly attenuated the H2O2-induced cytotoxicity in a concentration-dependent way. The maximum protective effects were 96.85±15.59% (rCramoll and 59.48±23.44% (pCramoll. The Live/Dead analysis showed a reduction in the percentage of dead cells from 65.04±3.29% (H2O2 to 39.77±2.93% (pCramoll and 13.90±9.01% (rCramoll. The deleterious effects of H2O2 on cell proliferation were reduced to 10.83% (pCramoll and 24.17% (rCramoll. Lectins treatment attenuated the excessive superoxide production, the collapse of the mitochondrial membrane potential, and the lysosomal and DNA damage in H2O2-treated cells. In conclusion, our results suggest that pCramoll and rCramoll blocked H2O2-induced cytotoxicity through decreasing reactive oxygen species, restoring the mitochondrial potential, preventing the lysosomal damage and DNA fragmentation, and thus promoting cell survival and proliferation.
Hossain, Mohammad A.; Bhattacharjee, Soumen; Armin, Saed-Moucheshi; Qian, Pingping; Xin, Wang; Li, Hong-Yu; Burritt, David J.; Fujita, Masayuki; Tran, Lam-Son P.
Plants are constantly challenged by various abiotic stresses that negatively affect growth and productivity worldwide. During the course of their evolution, plants have developed sophisticated mechanisms to recognize external signals allowing them to respond appropriately to environmental conditions, although the degree of adjustability or tolerance to specific stresses differs from species to species. Overproduction of reactive oxygen species (ROS; hydrogen peroxide, H2O2; superoxide, O2⋅-; hydroxyl radical, OH⋅ and singlet oxygen, 1O2) is enhanced under abiotic and/or biotic stresses, which can cause oxidative damage to plant macromolecules and cell structures, leading to inhibition of plant growth and development, or to death. Among the various ROS, freely diffusible and relatively long-lived H2O2 acts as a central player in stress signal transduction pathways. These pathways can then activate multiple acclamatory responses that reinforce resistance to various abiotic and biotic stressors. To utilize H2O2 as a signaling molecule, non-toxic levels must be maintained in a delicate balancing act between H2O2 production and scavenging. Several recent studies have demonstrated that the H2O2-priming can enhance abiotic stress tolerance by modulating ROS detoxification and by regulating multiple stress-responsive pathways and gene expression. Despite the importance of the H2O2-priming, little is known about how this process improves the tolerance of plants to stress. Understanding the mechanisms of H2O2-priming-induced abiotic stress tolerance will be valuable for identifying biotechnological strategies to improve abiotic stress tolerance in crop plants. This review is an overview of our current knowledge of the possible mechanisms associated with H2O2-induced abiotic oxidative stress tolerance in plants, with special reference to antioxidant metabolism. PMID:26136756
Mohammad A. Hossain
Full Text Available Plants are constantly challenged by various abiotic stresses that negatively affect growth and productivity worldwide. During the course of their evolution, plants have developed sophisticated mechanisms to recognize external signals allowing them to respond appropriately to environmental conditions, although the degree of adjustability or tolerance to specific stresses differs from species to species. Overproduction of reactive oxygen species (ROS (hydrogen peroxide, H2O2; superoxide, O2ˉ˙; hydroxyl radical, OH. and singlet oxygen, 1O2 is enhanced under abiotic and/or biotic stresses, which can cause oxidative damage to plant macromolecules and cell structures, leading to inhibition of plant growth and development, or to death. Among the various ROS, freely diffusible and relatively long-lived H2O2 acts as a central player in stress signal transduction pathways. These pathways can then activate multiple acclamatory responses that reinforce resistance to various abiotic and biotic stressors. To utilize H2O2 as a signaling molecule, non-toxic levels must be maintained in a delicate balancing act between H2O2 production and scavenging. Several recent studies have demonstrated that the H2O2-priming can enhance abiotic stress tolerance by modulating ROS detoxification and by regulating multiple stress-responsive pathways and gene expression. Despite the importance of the H2O2-priming, little is known about how this process improves the tolerance of plants to stress. Understanding the mechanisms of H2O2-priming-induced abiotic stress tolerance will be valuable for identifying biotechnological strategies to improve abiotic stress tolerance in crop plants. This review is an overview of our current knowledge of the possible mechanisms associated with H2O2-induced abiotic oxidative stress tolerance in plants, with special reference to antioxidant metabolism.
Hossain, Mohammad A; Bhattacharjee, Soumen; Armin, Saed-Moucheshi; Qian, Pingping; Xin, Wang; Li, Hong-Yu; Burritt, David J; Fujita, Masayuki; Tran, Lam-Son P
Plants are constantly challenged by various abiotic stresses that negatively affect growth and productivity worldwide. During the course of their evolution, plants have developed sophisticated mechanisms to recognize external signals allowing them to respond appropriately to environmental conditions, although the degree of adjustability or tolerance to specific stresses differs from species to species. Overproduction of reactive oxygen species (ROS; hydrogen peroxide, H2O2; superoxide, [Formula: see text]; hydroxyl radical, OH(⋅) and singlet oxygen, (1)O2) is enhanced under abiotic and/or biotic stresses, which can cause oxidative damage to plant macromolecules and cell structures, leading to inhibition of plant growth and development, or to death. Among the various ROS, freely diffusible and relatively long-lived H2O2 acts as a central player in stress signal transduction pathways. These pathways can then activate multiple acclamatory responses that reinforce resistance to various abiotic and biotic stressors. To utilize H2O2 as a signaling molecule, non-toxic levels must be maintained in a delicate balancing act between H2O2 production and scavenging. Several recent studies have demonstrated that the H2O2-priming can enhance abiotic stress tolerance by modulating ROS detoxification and by regulating multiple stress-responsive pathways and gene expression. Despite the importance of the H2O2-priming, little is known about how this process improves the tolerance of plants to stress. Understanding the mechanisms of H2O2-priming-induced abiotic stress tolerance will be valuable for identifying biotechnological strategies to improve abiotic stress tolerance in crop plants. This review is an overview of our current knowledge of the possible mechanisms associated with H2O2-induced abiotic oxidative stress tolerance in plants, with special reference to antioxidant metabolism.
Liu, Tao; Hu, Xiaohui; Zhang, Jiao; Zhang, Junheng; Du, Qingjie; Li, Jianming
Low temperature is a crucial factor influencing plant growth and development. The chlorophyll precursor, 5-aminolevulinic acid (ALA) is widely used to improve plant cold tolerance. However, the interaction between H 2 O 2 and cellular redox signaling involved in ALA-induced resistance to low temperature stress in plants remains largely unknown. Here, the roles of ALA in perceiving and regulating low temperature-induced oxidative stress in tomato plants, together with the roles of H 2 O 2 and cellular redox states, were characterized. Low concentrations (10-25 mg·L - 1 ) of ALA enhanced low temperature-induced oxidative stress tolerance of tomato seedlings. The most effective concentration was 25 mg·L - 1 , which markedly increased the ratio of reduced glutathione and ascorbate (GSH and AsA), and enhanced the activities of superoxide dismutase, catalase, ascorbate peroxidase, dehydroascorbate reductase, and glutathione reductase. Furthermore, gene expression of respiratory burst oxidase homolog1 and H 2 O 2 content were upregulated with ALA treatment under normal conditions. Treatment with exogenous H 2 O 2 , GSH, and AsA also induced plant tolerance to oxidative stress at low temperatures, while inhibition of GSH and AsA syntheses significantly decreased H 2 O 2 -induced oxidative stress tolerance. Meanwhile, scavenging or inhibition of H 2 O 2 production weakened, but did not eliminate, GSH- or AsA- induced tomato plant tolerance to oxidative stress at low temperatures. Appropriate concentrations of ALA alleviated the low temperature-induced oxidative stress in tomato plants via an antioxidant system. The most effective concentration was 25 mg·L - 1 . The results showed that H 2 O 2 induced by exogenous ALA under normal conditions is crucial and may be the initial step for perception and signaling transmission, which then improves the ratio of GSH and AsA. GSH and AsA may then interact with H 2 O 2 signaling, resulting in enhanced antioxidant capacity
Ye, Junsheng; Li, Juan; Yu, Yuming; Wei, Qiang; Deng, Wenfeng; Yu, Lixin
Oxidative stress has been considered as the possible mechanism of renal ischemia/reperfusion injury. L-carnitine is an endogenous mitochondrial membrane compound and could effectively protect ischemia-reperfusion injury in the kidney. To elucidate the nephroprotective effects of L-carnitine, here we assessed the effect of L-carnitine on hydrogen peroxide (H(2)O(2))-mediated oxidative stress in the human proximal tubule epithelial cell line, HK-2 cells. The results showed that pretreatment with L-carnitine 12h inhibited H(2)O(2)-induced cell viability loss, intracellular reactive oxygen species generation and lipid peroxidation in a concentration-dependent manner. Also L-carnitine promoted endogenous antioxidant defense components including total antioxidative capacity, glutathione peroxidase, catalase and superoxide dismutase. In parallel, cell apoptosis triggered by H(2)O(2) characterized with the DNA fragment and caspase-3 activity were also inhibited by L-carnitine. Furthermore, mitochondrial dysfunction associated with cell apoptosis including membrane potential loss, down-regulation of Bcl-2 and up-regulation of Bax and the release of cytochrome c were abrogated in the presence of L-carnitine. These results suggested that L-carnitine could protect HK-2 cells from H(2)O(2)-induced injury through the inhibition of oxidative damage, mitochondria dysfunction and ultimately inhibition of cell apoptosis, which indicates that L-carnitine may be a promising approach for the treatment of oxidative stress in renal diseases. Copyright 2010 Elsevier B.V. All rights reserved.
Full Text Available Resveratrol acts as a free radical scavenger and a potent antioxidant in the inhibition of numerous reactive oxygen species (ROS. The function of resveratrol and resveratrol-loaded nanoparticles in protecting human lung cancer cells (A549 against hydrogen peroxide was investigated in this study. The 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS assay was performed to evaluate the antioxidant properties. Resveratrol had substantially high antioxidant capacity (trolox equivalent antioxidant capacity value compared to trolox and vitamin E since the concentration of resveratrol was more than 50 μM. Nanoparticles prepared from β-lactoglobulin (β-lg were successfully developed. The β-lg nanoparticle showed 60 to 146 nm diameter in size with negatively charged surface. Non-cytotoxicity was observed in Caco-2 cells treated with β-lg nanoparticles. Fluorescein isothiocynate-conjugated β-lg nanoparticles were identified into the cell membrane of Caco-2 cells, indicating that nanoparticles can be used as a delivery system. Hydrogen peroxide caused accumulation of ROS in a dose- and time-dependent manner. Resveratrol-loaded nanoparticles restored H2O2-induced ROS levels by induction of cellular uptake of resveratrol in A549 cells. Furthermore, resveratrol activated nuclear factor erythroid 2-related factor 2-Kelch ECH associating protein 1 (Nrf2-Keap1 signaling in A549 cells, thereby accumulation of Nrf2 abundance, as demonstrated by western blotting approach. Overall, these results may have implications for improvement of oxidative stress in treatment with nanoparticles as a biodegradable and non-toxic delivery carrier of bioactive compounds.
Brand, A; Gil, S; Yavin, E
A major reason for brain tissue vulnerability to oxidative damage is the high content of polyunsaturated fatty acids (PUFAs). Oligodendroglia-like OLN 93 cells lack PUFAs and are relatively insensitive to oxidative stress. When grown in serum-free defined medium in the presence of 0.1 mM docosahexaenoic acid (DHA; 22:6 n-3) for 3 days, OLN 93 cells release in the medium 2.6-fold more thiobarbituric acid-reactive substances (TBARS) after a 30-min exposure to 0.1 mM H2O2 and 50 microM Fe2+. Release of TBARS was substantially decreased by approximately 20 and 30% on coincubation with either 1 mM N-monomethylethanolamine or N,N'-dimethylethanolamine (dEa), respectively. The protective effect of dEa was concentration- and time-dependent and was still visible after dEa removal, suggesting a long-lasting mechanism of protection. After 24 h following H2O2-induced stress, cell death monitored by cell sorting showed 16% of the cells in the sub-G1 area, indicative of apoptotic cell death. DHA-supplemented cultures showed 35% cell death, whereas cosupplements with dEa reduced cell death to 12%, indicating cell rescue. Although the exact mechanism for this protection is not known, the nature of the polar head group and the degree of unsaturation may determine the ultimate resistance of nerve cells to oxidative stress.
Iwami, Hisashi; Pruessner, Joachim; Shiraki, Kunihiko; Brinkmann, Ralf; Miura, Yoko
Recently introduced new technologies that enable temperature-controlled laser irradiation on the RPE allowed us to investigate temperature-resolved RPE cell responses. In this study we aimed primarily to establish an experimental setup that can realize laser irradiation on RPE cell culture with the similar temperature distribution as in the clinical application, with a precise time/temperature history. With this setup, we conducted investigations to elucidate the temperature-dependent RPE cell biochemical responses and the effect of transient hyperthermia on the responses of RPE cells to the secondary-exposed oxidative stress. Porcine RPE cells cultivated in a culture dish (inner diameter = 30 mm) with culture medium were used, on which laser radiation (λ = 1940 nm, spot diameter = 30 mm) over 10 s was applied as a heat source. The irradiation provides a radially decreasing temperature profile which is close to a Gaussian shape with the highest temperature in the center. Power setting for irradiation was determined such that the peak temperature (Tmax) in the center of the laser spot at the cells reaches from 40 °C to 58 °C (40, 43, 46, 50, 58 °C). Cell viability was investigated with ethidium homodimer III staining at the time points of 3 and 24 h following laser irradiation. Twenty four hours after laser irradiation the cells were exposed to hydrogen peroxide (H2O2) for 5 h, followed by the measurement of intracellular glutathione, intracellular 4-hydroxynonenal (HNE) protein adducts, and secreted vascular endothelial growth factor (VEGF). The mean temperature threshold for RPE cell death after 3 h was found to be around 52 °C, and for 24 h around 50 °C with the current irradiation setting. A sub-lethal preconditioning on Tmax = 43 °C significantly induced the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio, and decreased H2O2-induced increase of intracellular 4-HNE protein adducts. Although sub-lethal hyperthermia (Tmax
Full Text Available Fermented Chinese formula Shuan-Tong-Ling (STL, composed of fourteen medicinal herbs, was an experiential formula by Dr. Zhigang Mei for treating vascular encephalopathy, but the underlying mechanisms remained unknown. In this study, we aimed to investigate the protective effects of fermented STL on hydrogen peroxide- (H2O2- induced injury in rat brain microvascular endothelial cells (BMECs and the possible mechanisms. Cultured BMECs were treated with H2O2, STL, or nicotinamide (NAM, a SIRT1 inhibitor. Then, 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl-2H-tetrazolium bromide (MTT assay was employed to detect cell proliferation and senescence-associated beta-galactosidase (SA-β-gal was used to examine cell senescence. Cell nuclei were observed by 4′,6-diamidino-2-phenylindole. Additionally, changes in reactive oxygen species (ROS, superoxide dismutase (SOD, and glutathione (GSH levels were measured. Expression of SIRT1, p21, and PGC-1α was determined by western blot. Cell proliferation significantly increased with STL treatment in a dose-dependent manner. H2O2 treatment could intensify cell senescence and nuclei splitting or pyknosis. With STL treatment, the reduced ROS level was accompanied by increased SOD and GSH activity. Further assays showed upregulation of SIRT1 and PGC-1α and downregulation of p21 after STL treatment. The results revealed that STL could protect BMECs against oxidative stress injury at least partially through the SIRT1 pathway.
Qui, Shuang; Kano, Junko; Noguchi, Masayuki
Dickkopf (DKK) 3 is a DKK glycoprotein family member that controls cell fate during embryogenesis and exerts opposing effects on survival in a cell type-dependent manner; however, the mechanisms governing its pro-apoptosis versus pro-survival functions remain unclear. Here, we investigated DKK3 function in Li21 hepatoma cells and tPH5CH immortalized hepatocytes. DKK3 knockdown by siRNA resulted in reactive oxygen species accumulation and subsequent apoptosis, which were abrogated by administration of the antioxidant N-acetyl-cysteine. Moreover, forced DKK3 over-expression induced resistance to hydrogen peroxide (H2 O2 )-induced apoptosis. Expression analysis by cDNA microarray showed that xanthine dehydrogenase (XDH) expression was significantly lower in Li21 and tPH5CHDKK3-over-expressing cells in response to H2 O2 treatment when compared to that in their respective mock-transfected controls, whereas a marked increase was observed in H2 O2 -treated DKK3 knockdown cells. Thus, these data suggest that DKK3 promotes cell survival during oxidative stress by suppressing the expression of the superoxide-producing enzyme XDH. © 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.
Full Text Available Ultraviolet (UV radiation, particularly ultraviolet A (UVA, is known to play a major role in photoaging of the human skin. Many studies have demonstrated that UV exposure causes the skin cells to generate reactive oxygen species and activates the mitogen-activated protein kinase (MAPK pathway. Previous studies have also demonstrated that cycloheterophyllin has an antioxidant effect and can effectively scavenge free radicals. Extending the aforementioned investigations, in this study, human dermal fibroblasts were used to investigate the protective effect of cycloheterophyllin against UV-induced damage. We found that cycloheterophyllin not only significantly increased cell viability, but also attenuated the phosphorylation of MAPK after UVA exposure. Furthermore, cycloheterophyllin could reduce hydrogen peroxide (H2O2 generation and down-regulate H2O2-induced MAPK phosphorylation. In the in vivo studies, the topical application of cycloheterophyllin before UVA irradiation significantly decreased trans-epidermal water loss (TEWL, erythema, and blood flow rate. These results indicate that cycloheterophyllin is a photoprotective agent that inhibits UVA-induced oxidative stress and damage, and could be used in the research on and prevention of skin photoaging.
Full Text Available It has been reported that oxidant/antioxidant imbalance triggers cell damage that in turn causes a number of lung diseases. Flavonoids are known for their health benefits, and Citrus fruits juices are one of the main food sources of these secondary plant metabolites. The present study was designed to evaluate the effect of the flavonoid fraction of bergamot and orange juices, on H2O2-induced oxidative stress in human lung epithelial A549 cells. First we tested the antioxidant properties of both extracts in cell-free experimental models and then we assayed their capability to prevent the cytotoxic effects induced by H2O2. Our results demonstrated that both Citrus juice extracts reduce the generation of reactive oxygen species and membrane lipid peroxidation, improve mitochondrial functionality, and prevent DNA-oxidative damage in A549 cells incubated with H2O2. Our data indicate that the mix of flavonoids present in both bergamot and orange juices may be of use in preventing oxidative cell injury and pave the way for further research into a novel healthy approach to avoid lung disorders.
Ferlazzo, Nadia; Visalli, Giuseppa; Smeriglio, Antonella; Cirmi, Santa; Lombardo, Giovanni Enrico; Campiglia, Pietro; Di Pietro, Angela; Navarra, Michele
It has been reported that oxidant/antioxidant imbalance triggers cell damage that in turn causes a number of lung diseases. Flavonoids are known for their health benefits, and Citrus fruits juices are one of the main food sources of these secondary plant metabolites. The present study was designed to evaluate the effect of the flavonoid fraction of bergamot and orange juices, on H2O2-induced oxidative stress in human lung epithelial A549 cells. First we tested the antioxidant properties of both extracts in cell-free experimental models and then we assayed their capability to prevent the cytotoxic effects induced by H2O2. Our results demonstrated that both Citrus juice extracts reduce the generation of reactive oxygen species and membrane lipid peroxidation, improve mitochondrial functionality, and prevent DNA-oxidative damage in A549 cells incubated with H2O2. Our data indicate that the mix of flavonoids present in both bergamot and orange juices may be of use in preventing oxidative cell injury and pave the way for further research into a novel healthy approach to avoid lung disorders.
Shahzad, Muhammad; Small, David M; Morais, Christudas; Wojcikowski, Ken; Shabbir, Arham; Gobe, Glenda C
Astragalus membranaceus either alone or in combination with Angelica sinensis has been used traditionally for kidney disease in East Asia and China for thousands of years. Previous studies using in vivo animal models have shown the benefits of these medicinal herbs in kidney diseases that involve oxidative stress. However, the mechanisms by which these medicinal herbs protect kidney cells remain largely unknown. To investigate the mechanisms by which ethanol, methanol and aqueous crude extracts of roots of A. membranaceus and A. sinensis afford protection to human kidney proximal tubular epithelial cells, using an in vitro model of oxidative stress. Ethanol, methanol and aqueous extracts of roots of A. membranaceus and A. sinensis were prepared by a three-solvent sequential process. HK2 human kidney proximal tubular epithelial cells were treated with H2O2 alone (0.5mM) or in combination with different concentrations of extracts. Cell mitosis and death (microscopy) and cell viability (MTT assay) were compared. Western immunoblot was used to study expression of apoptosis-related proteins (pro-apoptotic Bax andanti-apoptotic Bcl-XL), and cell survival (NFκB subunits p65 and p50), pro-inflammatory (TNF-α) and protective (TGFβ1) proteins. H2O2-induced oxidative stress significantly increased apoptosis and reduced cell survival; upregulated pro-apoptotic and down-regulated Bcl-XL; increased NFκB (p65, p50); increased TNFα and decreased TGFβ1. All changes indicated kidney damage and dysfunction. All were modulated by all extracts of both plant species, except for NFκB which was only modulated by extracts of A. membranaceus. In conclusion, in a model of oxidative stress that might occur after nephrotoxicity, the plant extracts were protective via anti-apoptotic and anti-inflammatory mechanisms. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Willis, Jeremy; Patel, Yogin; Lentz, Barry L; Yan, Shan
The base excision repair pathway is largely responsible for the repair of oxidative stress-induced DNA damage. However, it remains unclear how the DNA damage checkpoint is activated by oxidative stress at the molecular level. Here, we provide evidence showing that hydrogen peroxide (H2O2) triggers checkpoint kinase 1 (Chk1) phosphorylation in an ATR [ataxia-telangiectasia mutated (ATM) and Rad3-related]-dependent but ATM-independent manner in Xenopus egg extracts. A base excision repair protein, Apurinic/apyrimidinic (AP) endonuclease 2 (APE2, APN2, or APEX2), is required for the generation of replication protein A (RPA)-bound single-stranded DNA, the recruitment of a checkpoint protein complex [ATR, ATR-interacting protein (ATRIP), and Rad9] to damage sites, and H2O2-induced Chk1 phosphorylation. A conserved proliferating cell nuclear antigen interaction protein box of APE2 is important for the recruitment of APE2 to H2O2-damaged chromatin. APE2 3'-phosphodiesterase and 3'-5' exonuclease activity is essential for single-stranded DNA generation in the 3'-5' direction from single-stranded breaks, referred to as single-stranded break end resection. In addition, APE2 associates with Chk1, and a serine residue (S86) in the Chk1-binding motif of APE2 is essential for Chk1 phosphorylation, indicating a Claspin-like but distinct role for APE2 in ATR-Chk1 signaling. Our data indicate that APE2 plays a vital and previously unexpected role in ATR-Chk1 checkpoint signaling in response to oxidative stress. Thus, our findings shed light on a distinct mechanism of how an ATR-Chk1-dependent DNA damage checkpoint is mediated by APE2 in the oxidative stress response.
Sextius, P; Betts, R; Benkhalifa, I; Commo, S; Eilstein, J; Massironi, M; Wang, P; Michelet, J-F; Qiu, J; Tan, X; Jeulin, S
To examine the ability of an extract from traditional Chinese medicine, Polygonum multiflorum Radix, to protect melanocyte viability from oxidative stress, a key mechanism in the initiation and progression of hair greying. To assess the antioxidant capacity of Polygonum multiflorum Radix extract, primary human foreskin melanocytes were treated with a commercially available Polygonum multiflorum Radix extract added to culture medium and exposed to hydrogen peroxide (H 2 O 2 ), using intracellular reactive oxygen species concentrations and glutathione/protein ratios as endpoints. To improve solubility for cosmetic uses, a new Polygonum multiflorum Radix extract was derived. As hair greying is the consequence of melanocyte disappearance in an oxidative stress environment, we checked whether the antioxidant capacity of the new Polygonum multiflorum Radix extract could preserve melanocyte viability in response to H 2 O 2 -induced oxidative stress, and preserve pigmentation within ex vivo human hair follicles. In vitro treatment of primary human foreskin melanocytes with traditional available Polygonum multiflorum Radix extract resulted in decreased intracellular ROS accumulation in response to H 2 O 2 exposure with a concomitant preservation of glutathione-to-protein ratio, consistent with a protective response against H 2 O 2 exposure and demonstrating the promise of this extract for protecting melanocytes against oxidative stress. Melanocytes treated with the improved Polygonum multiflorum Radix extract exhibited attenuated H 2 O 2 -induced cell death, demonstrating a clear cytoprotective effect. Treatment of ex vivo human hair follicles with the improved Polygonum multiflorum Radix extract resulted in a higher level of melanin compared to vehicle-treated controls, demonstrating an ex vivo protective effect on hair pigmentation. Polygonum multiflorum Radix extract protects in vitro primary human foreskin melanocytes from the deleterious effects of H 2 O 2
Saeed-Zidane, Mohammed; Linden, Lea; Salilew-Wondim, Dessie; Held, Eva; Neuhoff, Christiane; Tholen, Ernst; Hoelker, Michael; Schellander, Karl; Tesfaye, Dawit
Various environmental insults including diseases, heat and oxidative stress could lead to abnormal growth, functions and apoptosis in granulosa cells during ovarian follicle growth and oocyte maturation. Despite the fact that cells exposed to oxidative stress are responding transcriptionally, the potential release of transcripts associated with oxidative stress response into extracellular space through exosomes is not yet determined. Therefore, here we aimed to investigate the effect of oxidative stress in bovine granulosa cells in vitro on the cellular and exosome mediated defense mechanisms. Bovine granulosa cells were aspirated from ovarian follicles and cultured in DMEM/F-12 Ham culture medium supplemented with 10% exosome-depleted fetal bovine serum. In the first experiment sub-confluent cells were treated with 5 μM H2O2 for 40 min to induce oxidative stress. Thereafter, cells were subjected to ROS and mitochondrial staining, cell proliferation and cell cycle assays. Furthermore, gene and protein expression analysis were performed in H2O2-challenged versus control group 24 hr post-treatment using qRT-PCR and immune blotting or immunocytochemistry assay, respectively. Moreover, exosomes were isolated from spent media using ultracentrifugation procedure, and subsequently used for RNA isolation and qRT-PCR. In the second experiment, exosomes released by granulosa cells under oxidative stress (StressExo) or those released by granulosa cells without oxidative stress (NormalExo) were co-incubated with bovine granulosa cells in vitro to proof the potential horizontal transfer of defense molecules from exosomes to granulosa cells and investigate any phenotype changes. Exposure of bovine granulosa cells to H2O2 induced the accumulation of ROS, reduced mitochondrial activity, increased expression of Nrf2 and its downstream antioxidant genes (both mRNA and protein), altered the cell cycle transitions and induced cellular apoptosis. Granulosa cells exposed to oxidative
Shi, Q; Zhang, W; Guo, S; Jian, Z; Li, S; Li, K; Ge, R; Dai, W; Wang, G; Gao, T; Li, C
Oxidative stress has a critical role in the pathogenesis of vitiligo. However, the specific molecular mechanism involved in oxidative stress-induced melanocyte death is not well characterized. Given the powerful role of microRNAs (miRNAs) in the regulation of cell survival as well as the fact that the generation of miRNAs can be affected by oxidative stress, we hypothesized that miRNAs may participate in vitiligo pathogenesis by modulating the expression of vital genes in melanocytes. In the present study, we initially found that miR-25 was increased in both serum and lesion samples from vitiligo patients, and its serum level was correlated with the activity of vitiligo. Moreover, restoration of miR-25 promoted the H2O2-induced melanocyte destruction and led to the dysfunction of melanocytes. Further experiments proved that MITF, a master regulator in melanocyte survival and function, accounted for the miR-25-caused damaging impact on melanocytes. Notably, other than the direct role on melanocytes, we observed that miR-25 inhibited the production and secretion of SCF and bFGF from keratinocytes, thus impairing their paracrine protective effect on the survival of melanocytes under oxidative stress. At last, we verified that oxidative stress could induce the overexpression of miR-25 in both melanocytes and keratinocytes possibly by demethylating the promoter region of miR-25. Taken together, our study demonstrates that oxidative stress-induced overexpression of miR-25 in vitiligo has a crucial role in promoting the degeneration of melanocytes by not only suppressing MITF in melanocytes but also impairing the paracrine protective effect of keratinocytes. Therefore, it is worthy to investigate the possibility of miR-25 as a potential drug target for anti-oxidative therapy in vitiligo. PMID:26315342
Yan, Xu; Qiao, Yajun; Ouyang, Jiting; Jia, Mei; Li, Jiaxin; Yuan, Fang
Atmospheric pressure plasma jet (APPJ) can produce biological active species for biomedical applications. This work proves direct evidence of the protective effects of APPJ against oxidative stress. SH-SY5Y cells, a commonly used cell model for the study of neurotoxicity and neuroprotection, were treated with APPJ for different durations. Then, cells were exposed to 200 µM H2O2 for 24 h and cell viability was measured using a CCK-8 kit. Changes in cell apoptosis were further confirmed by calcein-AM fluorescence imaging and flow cytometry. Extracellular NO production was detected using the Griess method. The results showed that APPJ protected SH-SY5Y from H2O2-induced apoptosis in a time-dependent manner. Moreover, extracellular NO production was significantly increased with the APPJ treatment. The results show in vitro that APPJ treatment could protect SH-SY5Y cells from oxidative stress by reducing cell apoptosis, which might be related to the reactive nitrogen species induced by the APPJ treatment. Our results indicate that the APPJ may have therapeutic potential as a novel ‘NO donor drug’ in neuroprotection and in the treatment of neurodegenerative diseases.
Zhou, Aifen; He, Zhili; Redding, A.M.; Mukhopadhyay, Aindrila; Hemme, Christopher L.; Joachimiak, Marcin P.; Bender, Kelly S.; Keasling, Jay D.; Stahl, David A.; Fields, Matthew W.; Hazen, Terry C.; Arkin, Adam P.; Wall, Judy D.; Zhou, Jizhong
Response of Desulfovibrio vulgaris Hildenborough to hydrogen peroxide (H2O2, 1 mM) was investigated with transcriptomic, proteomic and genetic approaches. Microarray data demonstrated that gene expression was extensively affected by H2O2 with the response peaking at 120 min after H2O2 treatment. Genes affected include those involved with energy production, sulfate reduction, ribosomal structure and translation, H2O2 scavenging, posttranslational modification and DNA repair as evidenced by gene coexpression networks generated via a random matrix-theory based approach. Data from this study support the hypothesis that both PerR and Fur play important roles in H2O2-induced oxidative stress response. First, both PerR and Fur regulon genes were significantly up-regulated. Second, predicted PerR regulon genes ahpC and rbr2 were derepressedin Delta PerR and Delta Fur mutants and induction of neither gene was observed in both Delta PerR and Delta Fur when challenged with peroxide, suggesting possible overlap of these regulons. Third, both Delta PerR and Delta Fur appeared to be more tolerant of H2O2 as measured by optical density. Forth, proteomics data suggested de-repression of Fur during the oxidative stress response. In terms of the intracellular enzymatic H2O2 scavenging, gene expression data suggested that Rdl and Rbr2 may play major roles in the detoxification of H2O2. In addition, induction of thioredoxin reductase and thioredoxin appeared to be independent of PerR and Fur. Considering all data together, D. vulgaris employed a distinctive stress resistance mechanism to defend against increased cellular H2O2, and the temporal gene expression changes were consistent with the slowdown of cell growth at the onset of oxidative stress.
Full Text Available The effect of oxidative stress–induced by hydrogen peroxide (H2O2 on the analgesic effect of xylazine and dipyrone in 7-14 days old chicks was studied, compared with the control group that given plane tap water. H2O2, 0.5 % in water, induced oxidative stress in chicks by significantly lowering glutathione, rising malondialdehyde in plasma, whole brain during the day 7th, 10th, 14th of chicks old in comparison with the control group. The analgesic median effective doses (ED50 of xylazine and dipyrone in the control group were determined to be 0.79 and 65.3 mg/kg, intramuscularly (i.m., respectively whereas H2O2 treated groups decreased these values to be 0.31 and 37.2 mg/kg, i.m. by 61 and 43%, respectively. Intramuscular injection of xylazine and dipyrone at 0.5, 70 mg/kg respectively causes analgesia from electro-stimulation induced pain in 50, 66.67% respectively in control groups whereas H2O2 treated chicks increases the analgesic efficacy to be 83.33 and 83.33% respectively. Xylazine and dipyrone injection at 1 and 100 mg/kg, i.m. 15 minutes before formaldehyde injection in right planter foot of stressed chicks causes analgesia from pain induced by formaldehyde through significant increases in onset of lifting of formaldehyde injected foot, significantly decreases its lifting numbers, decreases the time elapsed of lifting of formaldehyde injected foot in comparison with the stressed control group that injected with saline in right planter foot. The data of this study indicate that H2O2-induced oxidative stress potentiate the analgesic efficacy of the central and peripheral analgesics of xylazine and dipyrone in chicks.
Nocchi, Linda; Daly, Donna M; Chapple, Christopher; Grundy, David
The incidence of bladder conditions such as overactive bladder syndrome and its associated urinary incontinence is highly prevalent in the elderly. However, the mechanisms underlying these disorders are unclear. Studies suggest that the urothelium forms a 'sensory network' with the underlying innervation, alterations in which, could compromise bladder function. As the accumulation of reactive oxygen species can cause functional alterations with age, the aim of this study was to investigate whether oxidative stress alters urothelial sensory signalling and whether the mechanism underlying the effect of oxidative stress on the urothelium plays a role in aging. Five-month-old(young) and 24-month-old (aged) mice were used. H2O2 , used to induce oxidative stress, resulted in an increase in bladder afferent nerve activity and urothelial intracellular calcium in preparations from young mice. These functional changes were concurrent with upregulation of TRPM8 in the urothelium. Moreover, application of a TRPM8 antagonist significantly attenuated the H2O2 -induced calcium responses. Interestingly, an upregulation of TRPM8 was also found in the urothelium from aged mice, where high oxidative stress levels were observed, together with a greater calcium response to the TRPM8 agonist WS12. Furthermore, these calcium responses were attenuated by pretreatment with the antioxidant N-acetyl-cysteine. This study shows that oxidative stress affects urothelial function involving a TRPM8-mediated mechanism and these effects may have important implications for aging. These data provide an insight into the possible mechanisms by which oxidative stress causes physiological alterations in the bladder, which may also occur in other organs susceptible to aging. © 2014 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.
Jou, Mei-Jie; Peng, Tsung-I; Reiter, Russel J; Jou, Shuo-Bin; Wu, Hong-Yueh; Wen, Shiau-Ting
Oxidative stress-induced mitochondrial dysfunction has been shown to play a crucial role in the pathogenesis of a wide range of diseases. Protecting mitochondrial function, therefore, is vital for cells to survive during these disease processes. In this study, we demonstrate that melatonin, a chief secretory product of the pineal gland, readily rescued mitochondria from oxidative stress-induced dysfunction and effectively prevented subsequent apoptotic events and death in rat brain astrocytes (RBA-1). The early protection provided by melatonin in mitochondria of intact living cells was investigated by the application of time-lapse conventional, confocal, and multiphoton fluorescent imaging microscopy coupled with noninvasive mitochondria-targeted fluorescent probes. In particular, we observed that melatonin effectively prevented exogenously applied H2O2-induced mitochondrial swelling in rat brain astrocytes at an early time point (within 10 min) and subsequently reduced apoptotic cell death (150 min later). Other early apoptotic events such as plasma membrane exposure of phosphatidyl serine and the positive YOPRO-1 staining of the early apoptotic nucleus were also prevented by melatonin. A mechanistic study at the mitochondrial level related to the early protection provided by melatonin revealed that the indole molecule significantly reduced mitochondrial reactive oxygen species (ROS) formation induced by H2O2 stress. Melatonin also prevented mitochondrial ROS generation caused by other organic hydroperoxides including tert-butyl hydroperoxide and cumene hydroperoxide. This antioxidative effect of melatonin is more potent than that of vitamin E. Via its ability to reduce mitochondrial ROS generation, melatonin prevented H2O2-induced mitochondrial calcium overload, mitochondrial membrane potential depolarization, and the opening of the mitochondrial permeability transition (MPT) pore. As a result, melatonin blocked MPT-dependent cytochrome c release, the downstream
Full Text Available Diabetic retinopathy is a common diabetic eye disease caused by changes in retinal ganglion cells (RGCs. It is an ocular manifestation of systemic disease, which affects up to 80% of all patients who have had diabetes for 10 years or more. The genetically diabetic db/db mouse, as a model of type-2 diabetes, shows diabetic retinopathy induced by apoptosis of RGCs. Astaxanthin is a carotenoid with powerful antioxidant properties that exists naturally in various plants, algae and seafood. Here, astaxanthin was shown to reduce the apoptosis of RGCs and improve the levels of oxidative stress markers, including superoxide anion, malondialdehyde (MDA, a marker of lipid peroxidation, 8-hydroxy-2-deoxyguanosine (8-OHdG, indicator of oxidative DNA damage and MnSOD (manganese superoxide dismutase activity in the retinal tissue of db/db mouse. In addition, astaxanthin attenuated hydrogen peroxide(H2O2-induced apoptosis in the transformed rat retinal ganglion cell line RGC-5. Therefore, astaxanthin may be developed as an antioxidant drug to treat diabetic retinopathy.
Background: The transcriptional regulatory network involved in low temperature response leading to acclimation has been established in Arabidopsis. In japonica rice, which can only withstand transient exposure to milder cold stress (10C), an oxidative-mediated network has been proposed to play a key role in configuring early responses and short-term defenses. The components, hierarchical organization and physiological consequences of this network were further dissected by a systems-level approach.Results: Regulatory clusters responding directly to oxidative signals were prominent during the initial 6 to 12 hours at 10C. Early events mirrored a typical oxidative response based on striking similarities of the transcriptome to disease, elicitor and wounding induced processes. Targets of oxidative-mediated mechanisms are likely regulated by several classes of bZIP factors acting on as1/ocs/TGA-like element enriched clusters, ERF factors acting on GCC-box/JAre-like element enriched clusters and R2R3-MYB factors acting on MYB2-like element enriched clusters.Temporal induction of several H2O2-induced bZIP, ERF and MYB genes coincided with the transient H2O2spikes within the initial 6 to 12 hours. Oxidative-independent responses involve DREB/CBF, RAP2 and RAV1 factors acting on DRE/CRT/rav1-like enriched clusters and bZIP factors acting on ABRE-like enriched clusters. Oxidative-mediated clusters were activated earlier than ABA-mediated clusters.Conclusion: Genome-wide, physiological and whole-plant level analyses established a holistic view of chilling stress response mechanism of japonica rice. Early response regulatory network triggered by oxidative signals is critical for prolonged survival under sub-optimal temperature. Integration of stress and developmental responses leads to modulated growth and vigor maintenance contributing to a delay of plastic injuries. 2010 Yun et al; licensee BioMed Central Ltd.
Giacoppo, Sabrina; Gugliandolo, Agnese; Trubiani, Oriana; Pollastro, Federica; Grassi, Gianpaolo; Bramanti, Placido; Mazzon, Emanuela
Research in the last decades has widely investigated the anti-oxidant properties of natural products as a therapeutic approach for the prevention and the treatment of oxidative-stress related disorders. In this context, several studies were aimed to evaluate the therapeutic potential of phytocannabinoids, the bioactive compounds of Cannabis sativa. Here, we examined the anti-oxidant ability of Cannabigerol (CBG), a non-psychotropic cannabinoid, still little known, into counteracting the hydrogen peroxide (H2O2)-induced oxidative stress in murine RAW264.7 macrophages. In addition, we tested selective receptor antagonists for cannabinoid receptors and specifically CB1R (SR141716A) and CB2R (AM630) in order to investigate through which CBG may exert its action. Taken together, our in vitro results showed that CBG is able to counteract oxidative stress by activation of CB2 receptors. CB2 antagonist pre-treatment indeed blocked the protective effects of CBG in H2O2 stimulated macrophages, while CB1R was not involved. Specifically, CBG exhibited a potent action in inhibiting oxidative stress, by down-regulation of the main oxidative markers (iNOS, nitrotyrosine and PARP-1), by preventing IκB-α phosphorylation and translocation of the nuclear factor-κB (NF-κB) and also via the modulation of MAP kinases pathway. On the other hand, CBG was found to increase anti-oxidant defense of cells by modulating superoxide dismutase-1 (SOD-1) expression and thus inhibiting cell death (results focused on balance between Bax and Bcl-2). Based on its anti-oxidant activities, CBG may hold great promise as an anti-oxidant agent and therefore used in clinical practice as a new approach in oxidative-stress related disorders. PMID:28348416
Johnson, Neal A.; Aruni, Wilson; Dou, Yuetan; Masinde, Godfred; Fletcher, Hansel M.
Porphyromonas gingivalis, an anaerobic oral pathogen implicated in adult periodontitis, can exist in an environment of oxidative stress. To evaluate its adaptation to this environment, we have assessed the response of P. gingivalis W83 to varying levels and durations of hydrogen peroxide (H2O2)-induced stress. When P. gingivalis was initially exposed to a subinhibitory concentration of H2O2 (0.1 mM), an adaptive response to higher concentrations could be induced. Transcriptome analysis demonstrated that oxidative stress can modulate several functional classes of genes depending on the severity and duration of the exposure. A 10 min exposure to H2O2 revealed increased expression of genes involved in DNA damage and repair, while after 15 min, genes involved in protein fate, protein folding and stabilization were upregulated. Approximately 9 and 2.8 % of the P. gingivalis genome displayed altered expression in response to H2O2 exposure at 10 and 15 min, respectively. Substantially more genes were upregulated (109 at 10 min; 47 at 15 min) than downregulated (76 at 10 min; 11 at 15 min) by twofold or higher in response to H2O2 exposure. The majority of these modulated genes were hypothetical or of unknown function. One of those genes (pg1372) with DNA-binding properties that was upregulated during prolonged oxidative stress was inactivated by allelic exchange mutagenesis. The isogenic mutant P. gingivalis FLL363 (pg1372 : : ermF) showed increased sensitivity to H2O2 compared with the parent strain. Collectively, our data indicate the adaptive ability of P. gingivalis to oxidative stress and further underscore the complex nature of its resistance strategy under those conditions. PMID:22745271
Full Text Available Research in the last decades has widely investigated the anti-oxidant properties of natural products as a therapeutic approach for the prevention and the treatment of oxidative-stress related disorders. In this context, several studies were aimed to evaluate the therapeutic potential of phytocannabinoids, the bioactive compounds of Cannabis sativa. Here, we examined the anti-oxidant ability of Cannabigerol (CBG, a non-psychotropic cannabinoid, still little known, into counteracting the hydrogen peroxide (H2O2-induced oxidative stress in murine RAW264.7 macrophages. In addition, we tested selective receptor antagonists for cannabinoid receptors and specifically CB1R (SR141716A and CB2R (AM630 in order to investigate through which CBG may exert its action. Taken together, our in vitro results showed that CBG is able to counteract oxidative stress by activation of CB2 receptors. CB2 antagonist pre-treatment indeed blocked the protective effects of CBG in H2O2 stimulated macrophages, while CB1R was not involved. Specifically, CBG exhibited a potent action in inhibiting oxidative stress, by down-regulation of the main oxidative markers (iNOS, nitrotyrosine and PARP-1, by preventing IκB-α phosphorylation and translocation of the nuclear factor-κB (NF-κB and also via the modulation of MAP kinases pathway. On the other hand, CBG was found to increase anti-oxidant defense of cells by modulating superoxide dismutase-1 (SOD-1 expression and thus inhibiting cell death (results focused on balance between Bax and Bcl-2. Based on its antioxidant activities, CBG may hold great promise as an anti-oxidant agent and therefore used in clinical practice as a new approach in oxidative-stress related disorders.
Chan, Jackie Yan-Yan; Tsui, Hei-Tung; Chung, Ivan Ying-Ming; Chan, Robbie Yat-Kan; Kwan, Yiu-Wa; Chan, Shun-Wan
Oxidative stress is considered an important factor that promotes cell death in response to a variety of pathophysiological conditions. This study investigated the antioxidant properties of allicin, the principle ingredient of garlic, on preventing oxidative stress-induced injury. The antioxidant capacities of allicin were measured by using 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay and hydrogen peroxide (H(2)O(2))-induced cell damage on H9c2 cardiomyoblasts. Allicin (0.3-10 μM) pre-incubation could concentration-dependently attenuate the intracellular reactive oxygen species (ROS) increase induced by H(2)O(2) on H9c2 cells. It could also protect H9c2 cells against H(2)O(2)-induced cell damage. However, the DPPH free radical scavenging activity of allicin was shown to be low. Therefore, it is believed that the protective effect of allicin on H9c2 cells could inhibit intracellular ROS production instead of scavenging extracellular H(2)O(2) or free radicals. For the observed protective effect on H9c2 cells, allicin might also be effective in reducing free radical-induced myocardial cell death in ischemic condition.
Bhakta, Dipita; Siva, Ramamoorthy
Plant dyes have been in use for coloring and varied purposes since prehistoric times. A red dye found in the roots of plants belonging to genus Morinda is a well recognized coloring ingredient. The dye fraction obtained from the methanolic extract of the roots of Morinda tinctoria was explored for its role in attenuating damages caused by H(2)O(2)-induced oxidative stress. The antioxidant potential of the dye fraction was assessed through DPPH radical scavenging, deoxyribose degradation and inhibition of lipid peroxidation in mice liver. It was subsequently screened for its efficiency in extenuating damage incurred to biomembrane (using erythrocytes and their ghost membranes) and macromolecules (pBR322 DNA, lipids and proteins) from exposure to hydrogen peroxide. In addition, the non-toxic nature of the dye was supported by the histological evaluation conducted on the tissue sections from the major organs of Swiss Albino mice as well as effect on Hep3B cell line (human hepatic carcinoma). The LC-MS confirms the dye fraction to be morindone. Our study strongly suggests that morindone present in the root extracts of M. tinctoria, in addition to being a colorant, definitely holds promise in the pharmaceutical industry. Copyright © 2012 Elsevier Ltd. All rights reserved.
Garcia, Gonçalo; Nanni, Sara; Figueira, Inês; Ivanov, Ines; McDougall, Gordon J; Stewart, Derek; Ferreira, Ricardo B; Pinto, Paula; Silva, Rui F M; Brites, Dora; Santos, Cláudia N
Neuroinflammation is an integral part of the neurodegeneration process inherent to several aging dysfunctions. Within the central nervous system, microglia are the effective immune cells, responsible for neuroinflammatory responses. In this study, raspberries were subjected to in vitro digestion simulation to obtain the components that result from the gastrointestinal (GI) conditions, which would be bioaccessible and available for blood uptake. Both the original raspberry extract and the gastrointestinal bioaccessible (GIB) fraction protected neuronal and microglia cells against H2O2-induced oxidative stress and lipopolysaccharide (LPS)-induced inflammation, at low concentrations. Furthermore, this neuroprotective capacity was independent of intracellular ROS scavenging mechanisms. We show for the first time that raspberry metabolites present in the GIB fraction significantly inhibited microglial pro-inflammatory activation by LPS, through the inhibition of Iba1 expression, TNF-α release and NO production. Altogether, this study reveals that raspberry polyphenols may present a dietary route to the retardation or amelioration of neurodegenerative-related dysfunctions. Copyright © 2016 Elsevier Ltd. All rights reserved.
Yan Y. Sanders
Full Text Available Aging and age-related diseases are associated with cellular senescence that results in variable apoptosis susceptibility to oxidative stress. Although fibroblast senescence has been associated with apoptosis resistance, mechanisms for this have not been well defined. In this report, we studied epigenetic mechanisms involving histone modifications that confer apoptosis resistance to senescent human diploid fibroblasts (HDFs. HDFs that undergo replicative senescence display typical morphological features, express senescence-associated β-galactosidase, and increased levels of the tumor suppressor genes, p16, p21, and caveolin-1. Senescent HDFs are more resistant to oxidative stress (exogenous H2O2-induced apoptosis in comparison to non-senescent (control HDFs; this is associated with constitutively high levels of the anti-apoptotic gene, Bcl-2, and low expression of the pro-apoptotic gene, Bax. Cellular senescence is characterized by global increases in H4K20 trimethylation and decreases in H4K16 acetylation in association with increased activity of Suv420h2 histone methyltransferase (which targets H4K20, decreased activity of the histone acetyltransferase, Mof (which targets H4K16, as well as decreased total histone acetyltransferase activity. In contrast to Bax gene, chromatin immunoprecipitation studies demonstrate marked enrichment of the Bcl-2 gene with H4K16Ac, and depletion with H4K20Me3, predicting active transcription of this gene in senescent HDFs. These data indicate that both global and locus-specific histone modifications of chromatin regulate altered Bcl-2:Bax gene expression in senescent fibroblasts, contributing to its apoptosis-resistant phenotype.
Basov, A A; Bykov, I M
The effect of nutritional correction (a diet high in foods with antioxidant content) on blood parameters in laboratory animals with metabolic disorders associated with oxidative stress has been studied. In experimental models of laboratory animals (male rabbits weighing 3.5-4.0 kg, n = 40) with purulent septic diseases it has been demonstrated that the use of nutritive correction (replacement of 100 g of the cereal mixture through day on a mixture of cabbage 50 g, carrots 50 g, beet 25 g, apple 25 g, kiwi 10 g and garnet 10 g per 1 rabbit) is not inferior to its efficiency of glutathione use (2 g per day). The use of these antioxidants in laboratory animals significantly reduced the phenomenon of oxidative stress on the 5th day: blood antioxidant capacity significantly increased by 14.9 and 26.6%, and the area of the flash of luminol-dependent H2O2-induced chemiluminescence of blood plasma reduced by 44.2 and 48.6% in the experimental groups receiving respectively nutritive correction and glutathione. The low-molecula level of blood antioxidant capacity was restored and the balance of the activity of superoxide dismutase (decrease) and catalase (increase) was achieved on the 10th day of the experiment. These figures significantly (p < 0.05) differed from than in the group of animals receiving no antioxidant correction. The latter studied parameters of prooxidant-antioxidant system reached values comparable with those in intact animals (n = 10) only on the 30th day, confirming the advisability of appointing a complex antioxidant therapy.
Rojo, Ana I; Sagarra, María Rosa de; Cuadrado, Antonio
Oxidant injury activates the neuroprotective pathway represented by phosphatidylinositol 3 kinase (PI3K) and Akt. However, the final outcome of oxidant exposure is often associated with neuronal death. This study was aimed to identify the molecular mechanism responsible for loss of tolerance to an oxidative environment. In N2A neuroblasts, serum and H2O2 exhibited different kinetics of regulation for the Ser/Thr kinases Akt and glycogen synthase kinase 3beta (GSK-3beta) and for the transcription factor Nrf2, which governs redox homeostasis. Thus, H2O2 rapidly activated Akt, inhibited GSK-3beta, and directed the transcription factor Nrf2 to the nucleus, but after 4 h Akt was inactive, GSK-3beta was active and Nrf2 was more cytosolic than nuclear. Inhibition of the PI3K/Akt pathway by LY294002, impeded the short-term effect of H2O2 on nuclear translocation of Nrf2. GSK-3beta activation (inhibiting PI3K/Akt) or direct GSK-3beta inhibition in cerebellar granule neurons resulted in respective nuclear exclusion and nuclear accumulation of Nrf2. Moreover, in these neurons, nuclear accumulation of Nrf2 correlated with increased heme oxygenase-1 expression. Over-expression of the kinase active GSK-3beta (Delta9) mutant, induced Nrf2 cytoplasmic localization and inhibited Nrf2 transcriptional activity towards an antioxidant-response-element luciferase reporter. Moreover, GSK-3beta (Delta9) sensitized N2A neuroblasts to H2O2-induced oxidative stress and cell death. This study identifies GSK-3beta, a kinase known to participate in neurodegeneration, as a fundamental element in the down-regulation of the antioxidant cell defense elicited by Nrf2 after oxidant injury and provides a mechanism to explain the loss of oxidant tolerance that happens under persistent oxidant exposure such as those found in several neuropathologies.
Tan, Sang-Nee; Sim, Sai-Peng; Khoo, Alan S B
Genetic aberrations have been identified in nasopharyngeal carcinoma (NPC), however, the underlying mechanism remains elusive. There are increasing evidences that the apoptotic nuclease caspase-activated deoxyribonuclease (CAD) is one of the players leading to translocation in leukemia. Oxidative stress, which has been strongly implicated in carcinogenesis, is a potent apoptotic inducer. Most of the NPC etiological factors are known to induce oxidative stress. Although apoptosis is a cell death process, cells possess the potential to survive apoptosis upon DNA repair. Eventually, the surviving cells may carry rearranged chromosomes. We hypothesized that oxidative stress-induced apoptosis may cause chromosomal breaks mediated by CAD. Upon erroneous DNA repair, cells that survive apoptosis may harbor chromosomal rearrangements contributing to NPC pathogenesis. This study focused on the AF9 gene at 9p22, a common deletion region in NPC. We aimed to propose a possible model for molecular mechanism underlying the chromosomal rearrangements in NPC. In the present study, we showed that hydrogen peroxide (H2O2) induced apoptosis in NPC (HK1) and normal nasopharyngeal epithelial (NP69) cells, as evaluated by flow cytometric analyses. Activity of caspases 3/7 was detected in H2O2-treated cells. This activity was inhibited by caspase inhibitor (CI). By nested inverse polymerase chain reaction (IPCR), we demonstrated that oxidative stress-induced apoptosis in HK1 and NP69 cells resulted in cleavages within the breakpoint cluster region (BCR) of the AF9 gene. The gene cleavage frequency detected in the H2O2-treated cells was found to be significantly higher than untreated control. We further found that treatment with CI, which indirectly inhibits CAD, significantly reduced the chromosomal breaks in H2O2-cotreated cells. Intriguingly, a few breakpoints were mapped within the AF9 region that was previously reported to translocate with the mixed lineage leukemia (MLL) gene in
Full Text Available It has been demonstrated that oxidative stress has a ubiquitous role in neurodegenerative diseases. Major source of oxidative stress due to reactive oxygen species (ROS is related to mitochondria as an endogenous source. Although there is ample evidence from tissues of patients with neurodegenerative disorders of morphological, biochemical, and molecular abnormalities in mitochondria, it is still not very clear whether the oxidative stress itself contributes to the onset of neurodegeneration or it is part of the neurodegenerative process as secondary manifestation. This paper begins with an overview of how oxidative stress occurs, discussing various oxidants and antioxidants, and role of oxidative stress in diseases in general. It highlights the role of oxidative stress in neurodegenerative diseases like Alzheimer's, Parkinson's, and Huntington's diseases and amyotrophic lateral sclerosis. The last part of the paper describes the role of oxidative stress causing deregulation of cyclin-dependent kinase 5 (Cdk5 hyperactivity associated with neurodegeneration.
Sindhu, Sardar; Akhter, Nadeem; Kochumon, Shihab; Thomas, Reeby; Wilson, Ajit; Shenouda, Steve; Tuomilehto, Jaakko; Ahmad, Rasheed
Metabolic diseases such as obesity and type-2 diabetes (T2D) are known to be associated with chronic low-grade inflammation called metabolic inflammation together with an oxidative stress milieu found in the expanding adipose tissue. The innate immune Toll-like receptors (TLR) such as TLR2 and TLR4 have emerged as key players in metabolic inflammation; nonetheless, TLR10 expression in the adipose tissue and its significance in obesity/T2D remain unclear. TLR10 gene expression was determined in the adipose tissue samples from healthy non-diabetic and T2D individuals, 13 each, using real-time RT-PCR. TLR10 protein expression was determined by immunohistochemistry, confocal microscopy, and flow cytometry. Regarding in vitro studies, THP-1 cells, peripheral blood mononuclear cells (PBMC), or primary monocytes were treated with hydrogen peroxide (H2O2) for induction of reactive oxygen species (ROS)-mediated oxidative stress. Superoxide dismutase (SOD) activity was measured using a commercial kit. Data (mean±SEM) were compared using unpaired student's t-test and Poxidative stress induced high levels of TLR10 gene/protein expression in monocytic cells and PBMC. In these cells, oxidative stress induced a time-dependent increase in SOD activity. Pre-treatment of cells with anti-oxidants/ROS scavengers diminished the expression of TLR10. ROS-induced TLR10 expression involved the nuclear factor-kappaB (NF-κB)/mitogen activated protein kinase (MAPK) signaling as well as endoplasmic reticulum (ER) stress. H2O2-induced oxidative stress interacted synergistically with palmitate to trigger the expression of TLR10 which associated with enhanced expression of proinflammatory cytokines/chemokine. Oxidative stress induces the expression of TLR10 which may represent an immune marker for metabolic inflammation. © 2018 The Author(s). Published by S. Karger AG, Basel.
Yan, Xiaofei; Xun, Meng; Dou, Xiaojuan; Wu, Litao; Zhang, Fujun; Zheng, Jin
Reduced Na+-K+-ATPase activity has close relationship with cardiomyocyte death. Reactive oxygen species (ROS) also plays an important role in cardiac cell damage. It has been proved that Na+-K+-ATPase and ROS form a feed-forward amplifier. The aim of this study was to explore whether DRm217, a proved Na+/K+-ATPase's DR-region specific monoclonal antibody and direct activator, could disrupt Na+-K+-ATPase/ROS amplifier and protect cardiac cells from ROS-induced injury. We found that DRm217 protected myocardial cells against hydrogen peroxide (H2O2)-induced cardiac cell injury and mitochondrial dysfunction. DRm217 also alleviated the effect of H2O2 on inhibition of Na+-K+-ATPase activity, Na+-K+-ATPase cell surface expression, and Src phosphorylation. H2O2-treatment increased intracellular ROS, mitochondrial ROS and induced intracellular Ca2+, mitochondrial Ca2+ overload. DRm217 closed Na+-K+-ATPase/ROS amplifier, alleviated Ca2+ accumulation and finally inhibited ROS and mitochondrial ROS generation. These novel results may help us to understand the important role of the Na+-K+-ATPase in oxidative stress and oxidative stress-related disease.
Giddabasappa, Anand; Bauler, Matthew N; Barrett, Christina M; Coss, Christopher C; Wu, Zhongzhi; Miller, Duane D; Dalton, James T; Eswaraka, Jeetendra R
The goal of this study was to determine whether an estrogen receptor-β (ERβ)-selective agonist (GTx-822; GTx, Inc., Memphis, TN) could prevent hydrogen peroxide (H(2)O(2))-induced oxidative stress in ARPE-19 cells and to elucidate the molecular pathways involved in this protection. The selectivity of GTx-822 for ERβ was determined by receptor-binding assay (RBA) and transactivation assay. Cultured ARPE-19 cells were subjected to oxidative stress with t-butyl hydroxide (t-BH) or hydrogen peroxide (H(2)O(2)) in the presence and absence of GTx-822. Reactive oxygen species (ROS) was measured by using H(2)DCFDA fluorescence. Apoptosis was evaluated by cell death ELISA. Mitochondrial membrane potential was measured with the JC-1 assay. Gene expression and protein expression and activation were quantitated with qRT-PCR and Western blot analysis. Phospho-protein arrays elucidated the activation of protein kinases. The RBA and transactivation assay revealed that GTx-822 is an ERβ-selective agonist (K(i) = 0.53 nM). GTx-822 prevented oxidative stress in ARPE-19 cells. It preserved mitochondrial function and prevented cellular apoptosis. Pretreatment with GTx-822 increased ERβ gene and protein expression during oxidative stress. Upregulation of the phase II antioxidant genes GPx-2 and HO-1 was also seen in an ERβ-dependent mechanism. GTx-822 pretreatment induced phosphorylation of ERK1/2, PI3-K, and Bad. This is the first report to show that GTx-822, an ERβ agonist, can protect ARPE-19 cells from the cellular apoptosis induced by oxidative stress. GTx-822 mediated cytoprotection was mediated through induction of both genomic and nongenomic pathways. The results of this study open new avenues for the use of a selective ERβ agonist in treatment of ocular diseases like AMD where oxidative stress plays a major role in disease pathogenesis.
Full Text Available Olga Baraldi,1 Francesca Bianchi,2,3 Viola Menghi,1 Andrea Angeletti,1 Anna Laura Croci Chiocchini,1 Maria Cappuccilli,1 Valeria Aiello,1 Giorgia Comai,1 Gaetano La Manna1 1Department of Experimental, Diagnostic and Specialty Medicine, Nephrology, Dialysis and Renal Transplant Unit, Sant’Orsola-Malpighi Hospital, University of Bologna, Bologna, 2Stem Wave Institute for Tissue Healing, Gruppo Villa Maria Care & Research – Ettore Sansavini Health Science Foundation, Lugo, Ravenna, 3National Institute of Biostructures and Biosystems at the Department of Experimental, Diagnostic and Specialty Medicine, Sant’Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy Background: Acute kidney injury, known as a major trigger for organ fibrosis and independent predictor of chronic kidney disease, is characterized by mesangial cell proliferation, inflammation and unbalance between biosynthesis and degradation of extracellular matrix. Therapeutic approaches targeting the inhibition of mesangial cell proliferation and matrix expansion may represent a promising opportunity for the treatment of kidney injury. An ester of hyaluronic acid and butyric acid (HB has shown vasculogenic and regenerative properties in renal ischemic-damaged tissues, resulting in enhanced function recovery and minor degree of inflammation in vivo. This study evaluated the effect of HB treatment in mesangial cell cultures exposed to H2O2-induced oxidative stress.Materials and methods: Lactate dehydrogenase release and caspase-3 activation were measured using mesangial cells prepared from rat kidneys to assess necrosis and apoptosis. Akt and p38 phosphorylation was analyzed to identify the possible mechanism underlying cell response to HB treatment. The relative expressions of matrix metallopeptidase 9 (MPP-9 and collagen type 1 alpha genes were also analyzed by quantitative real-time polymerase chain reaction. Cell proliferation rate and viability were measured using
Full Text Available Glycogen synthase kinase-3β (GSK-3β acts as a negative regulator of NF-E2 related factor 2 (Nrf2 by inducing Nrf2 degradation and nuclear export. Our previous study demonstrated that the flavonoid hyperoside elicits cytoprotection against oxidative stress by activating the Keap1-Nrf2-ARE signaling pathway, thus increasing the expression of antioxidant enzymes, such as heme oxygenase-1 (HO-1, superoxide dismutase (SOD and catalase. However, the role of GSK-3β in hyperoside-mediated Nrf2 activation is unclear. Here, we demonstrate that in a normal human hepatocyte cell line, (L02, hyperoside is capable of inducing the phosphorylation of GSK-3β at Ser9 without affecting the protein levels of GSK-3β and its phosphorylation at Thr390. Lithium chloride (LiCl and short interfering RNA (siRNA-mediated inhibition of GSK-3β significantly enhanced the ability of hyperoside to protect L02 liver cells from H2O2-induced oxidative damage, leading to increased cell survival shown by the maintenance of cell membrane integrity and elevated levels of glutathione (GSH, one of the endogenous antioxidant biomarkers. Further study showed that LiCl and siRNA-mediated inhibition of GSK-3β increased hyperoside-induced HO-1 expression, and the effect was dependent upon enhanced Nrf2 nuclear translocation and gene expression. These activities were followed by ARE-mediated transcriptional activation in the presence of hyperoside, which was abolished by the transfection of the cells with Nrf2 siRNA. Furthermore, the siRNA-mediated inhibition of Keap1 also enhanced hyperoside-induced Nrf2 nuclear accumulation and HO-1 expression, which was relatively smaller than the effects obtained from GSK-3β siRNA administration. Moreover, Keap1 siRNA administration alone had no significant effect on the phosphorylation and protein expression of GSK-3β. Collectively, our data provide evidence that hyperoside attenuates H2O2 -induced L02 cell damage by activating the Nrf2-ARE
Basiricò, L; Morera, P; Dipasquale, D; Tröscher, A; Bernabucci, U
Some in vitro and in vivo studies have demonstrated protective effects of conjugated linoleic acid (CLA) isomers against oxidative stress and lipid peroxidation. However, only a few and conflicting studies have been conducted showing the antioxidant potential of essential fatty acids. The objectives of the study were to compare the effects of CLA to other essential fatty acids on the thiol redox status of bovine mammary epithelia cells (BME-UV1) and their protective role against oxidative damage on the mammary gland by an in vitro study. The BME-UV1 cells were treated with complete medium containing 50 μM of cis-9,trans-11 CLA, trans-10,cis-12 CLA, α-linolenic acid, γ-linolenic acid, and linoleic acid. To assess the cellular antioxidant response, glutathione, NADPH, and γ-glutamyl-cysteine ligase activity were measured 48 h after addition of fatty acids (FA). Intracellular reactive oxygen species and malondialdehyde production were also assessed in cells supplemented with FA. Reactive oxygen species production after 3 h of H2O2 exposure was assessed to evaluate and to compare the potential protection of different FA against H2O2-induced oxidative stress. All FA treatments induced an intracellular GSH increase, matched by high concentrations of NADPH and an increase of γ-glutamyl-cysteine ligase activity. Cells supplemented with FA showed a reduction in intracellular malondialdehyde levels. In particular, CLA isomers and linoleic acid supplementation showed a better antioxidant cellular response against oxidative damage induced by H2O2 compared with other FA. The Authors. Published by the Federation of Animal Science Societies and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).
Ali, Abid; Rahman, Khalilur; Jahan, Nazish; Jamil, Amer; Rashid, Abid; Shah, Syed Muhammad Ali
Medicinal plants are rich in secondary metabolites (alkoloids, glycosides, coumarins, flavonides, steroids, etc.) and considered to be more effective and a safer alternative source to manage a variety of diseases related to liver, heart and kidney disordered. This study determines in vitro antioxidant and in vivo toxicological profile including hemolytic, brine shrimp lethality and mutagenicity of aerial parts of Artemisia absinthium. DNA protection assay was performed on pUC19 plasmid vector using H(2)O(2) as oxidative agent. Total phenolic and flavonoid content were determined using colorimetric methods. Toxicity of the plant was evaluated by brine shrimp lethality, hemolytic and mutagenic activity. DNA protection assay of the plant showed concentration dependent protective effect and at concentration 10μL/mL revealed complete protective effect against H(2)O(2) induced DNA damage. Highest phenolic and flavonoid content was found to be 167.3 (mg GAE 100g DW(-1)) and 14 (mg CE 100g DW(-1)) respectively. Results showed that A. absinthium is potent against standard toxicological procedures, that indicates the presence of bioactive components in the plant and possess antioxidant activity that protects DNA against H(2)O(2) induced oxidative damage. Thus the results showed/support that A. absinthium provides significant health benefits.
Mishra, A; Reddy, I J; Gupta, P S P; Mondal, S
The objective of this study was to find out the effect of L-carnitine on oocyte maturation and subsequent embryo development, with L-carnitine-mediated alteration if any in transcript level of antioxidant enzymes (GPx, Cu/Zn-SOD (SOD1) and Mn-SOD (SOD2) in oocytes and developing sheep embryos produced in vitro. Different concentrations of L-carnitine (0 mm, 2.5 mm, 5 mm, 7.5 mm and 10 mm) were used in maturation medium. Oocytes matured with 10 mm L-carnitine showed significantly (p L-carnitine were not significantly different. Maturation rate was not influenced by supplementation of any experimental concentration of L-carnitine. There was a significant (p L-carnitine-treated oocytes and embryos than control group. Antioxidant effect of L-carnitine was proved by culturing oocytes and embryos with H2O2 in the presence of L-carnitine which could be able to protect oocytes and embryos from H2O2-induced oxidative damage. L-carnitine supplementation significantly (p L-carnitine supplementation during in vitro maturation reduces oxidative stress-induced embryo toxicity by decreasing intracellular ROS and increasing intracellular GSH that in turn improved developmental potential of oocytes and embryos and alters transcript level of antioxidant enzymes. © 2016 Blackwell Verlag GmbH.
Ghaffari, Hadi; Ghassam, Behrouz Jalali; Chandra Nayaka, S; Ramachandra Kini, K; Prakash, H S
The present study was carried out to investigate the antioxidant and neuroprotective effects of Hyptis suaveolens methanol extract (HSME) using various in vitro systems. The total phenol and flavonoids contents of the HSME were quantified by colorimetric methods. The HSME extract exhibited potent antioxidant activity as determined by 2,20-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, 2,2-diphenyl-1-picrylhydrazyl, and ferric reducing antioxidant power assays. The neuroprotective activity of HSME was determined on mouse N2A neuroblastoma cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, lactate dehydrogenase, intracellular ROS assays, and upregulation of brain neuronal markers at genetic level. The N2A cells were pretreated with different concentrations (0.5, 1, 1.5, and 2 mg/ml) of the extract and then exposed to H2O2 to induce oxidative stress and neurotoxicity. The survival of the cells treated with different concentrations of HSME and H2O2 increased as compared to cells exposed only to H2O2 (47.3 %) (p < 0.05). The HSME also dose-dependently reduced LDH leakage and intracellular ROS production (p < 0.05). Pretreatment with HSME promotes the upregulation of tyrosine hydroxylase (2.41-fold, p < 0.05), and brain-derived neurotrophic factor genes (2.15-fold, p < 0.05) against H2O2-induced cytotoxicity in N2A cells. Moreover, the HSME showed antioxidant activity and decreased neurotoxicity. These observations suggest that HSME have marked antioxidant and neuroprotective activities.
Characterization of Mycobacterium smegmatis sigF mutant and its regulon: overexpression of SigF antagonist (MSMEG_1803) in M. smegmatis mimics sigF mutant phenotype, loss of pigmentation, and sensitivity to oxidative stress.
Singh, Anirudh K; Dutta, Debashis; Singh, Vandana; Srivastava, Vishal; Biswas, Rajesh K; Singh, Bhupendra N
In Mycobacterium smegmatis, sigF is widely expressed during different growth stages and plays role in adaptation to stationary phase and oxidative stress. Using a sigF deletion mutant of M. smegmatis mc(2) 155, we demonstrate that SigF is not essential for growth of bacterium. Deletion of sigF results in loss of carotenoid pigmentation which rendered increased susceptibility to H2 O2 induced oxidative stress in M. smegmatis. SigF modulates the cell surface architecture and lipid biosynthesis extending the repertoire of SigF function in this species. M. smegmatis SigF regulon included variety of genes expressed during exponential and stationary phases of growth and those responsible for oxidative stress, lipid biosynthesis, energy, and central intermediary metabolism. Furthermore, we report the identification of a SigF antagonist, an anti-sigma factor (RsbW), which upon overexpression in M. smegmatis wild type strain produced a phenotype similar to M. smegmatis mc(2) 155 ΔsigF strain. The SigF-anti-SigF interaction is duly validated using bacterial two-hybrid and pull down assays. In addition, anti-sigma factor antagonists, RsfA and RsfB were identified and their interactions with anti-sigma factor were experimentally validated. Identification of these proteins will help decode regulatory circuit of this alternate sigma factor. © 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.
Barlaka, Eleftheria; Görbe, Anikó; Gáspár, Renáta; Pálóczi, János; Ferdinandy, Péter; Lazou, Antigone
Heart failure still remains one of the leading causes of morbidity and mortality worldwide. A major contributing factor is reactive oxygen/nitrogen species (RONS) overproduction which is associated with cardiac remodeling partly through cardiomyocyte apoptosis. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that belong to the nuclear receptor superfamily and have been implicated in cardioprotection. However, the molecular mechanisms are largely unexplored. In this study we sought to investigate the potential beneficial effects evoked by activation of PPARβ/δ under the setting of oxidative stress induced by H2O2 in adult rat cardiac myocytes. The selective PPARβ/δ agonist GW0742 inhibited the H2O2-induced apoptosis and increased cell viability. In addition, generation of RONS was attenuated in cardiac myocytes in the presence of PPARβ/δ agonist. These effects were abolished in the presence of the PPARβ/δ antagonist indicating that the effect was through PPARβ/δ receptor activation. Treatment with PPARβ/δ agonist was also associated with attenuation of caspase-3 and PARP cleavage, upregulation of anti-apoptotic Bcl-2 and concomitant downregulation of pro-apoptotic Bax. In addition, activation of PPARβ/δ inhibited the oxidative-stress-induced MMP-2 and MMP-9 mRNA upregulation. It is concluded that PPARβ/δ activation exerts a cytoprotective effect in adult rat cardiac myocytes subjected to oxidative stress via inhibition of oxidative stress, MMP expression, and apoptosis. Our data suggest that the novel connection between PPAR signaling and MMP down-regulation in cardiac myocytes might represent a new target for the management of oxidative stress-induced cardiac dysfunction. Copyright © 2015 Elsevier Ltd. All rights reserved.
Zou, Yi; Wang, Jun; Peng, Jian
Oregano essential oil (OEO) has long been used to improve the health of animals, particularly their intestinal health. The health benefits of OEO are generally attributed to antioxidative actions, but the mechanisms remain unclear. Here, we investigate the antioxidative effects of OEO and their underlying molecular mechanisms in porcine small intestinal epithelial (IPEC-J2) cells. We found that OEO treatment prior to hydrogen peroxide (H2O2) exposure increased cell viability and prevented lactate dehydrogenase (LDH) release into the medium. H2O2-induced reactive oxygen species (ROS) and malondialdehyde (MDA) were remarkably suppressed by OEO. OEO dose-dependently increased mRNA and protein levels of the nuclear factor-erythroid 2-related factor-2 (Nrf2) target genes Cu/Zn-superoxide dismutase (SOD1) and g-glutamylcysteine ligase (GCLC, GLCM), as well as intracellular concentrations of SOD1 and glutathione. OEO also increased intranuclear expression of Nrf2 and the activity of an antioxidant response element reporter plasmid in IPEC-J2 cells. The OEO-induced expression of Nrf2-regulated genes and increased SOD1 and glutathione concentrations in IPEC-J2 cells were reduced by Nrf2 small interfering (si) RNAs, counteracting the protective effects of OEO against oxidative stress in IPEC-J2 cells. Our results suggest that OEO protects against H2O2-induced IPEC-J2 cell damage by inducing Nrf2 and related antioxidant enzymes. PMID:28105249
Pan, Y; Qiao, Q Y; Pan, L H; Zhou, D C; Hu, C; Gu, H F; Fu, S K; Liu, X L; Jin, H M
Inhibition of the rennin-angiotensin system (RAS) could reduce insulin resistance in patients with hypertension and diabetic kidney disease (DKD), but whether the effect of losartan on insulin resistance is associated with reduction of oxidative stress and enhancement of insulin signaling transduction has not been fully elucidated. 130 patients with type 2 DKD were randomly assigned into 2 groups, the losartan group (n=65, 100 mg orally daily for 12 months) and the amlodipine group (n=65, 10 mg orally daily for 12 months). Oxidative stress markers in plasma, urine concentrations of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and nitrotyrosine (NT) as well as SOD activity were measured by ELISA. After in vitro treatment with different doses of losartan (10, 100 μmol/L) or amlodipine for 48 h, the size of H2O2-induced adipocytes and glucose consumption were measured. Western blot was performed to investigate IRS-1 serine phosphorylation level as well as the protein expressions of phosphorylated insulin receptor (pIR), phosphatidylinositol 3- kinase (PI3K) and insulin receptor substrate 1 (IRS-1) in 3T3-L1 adipocytes. After 12-month treatment, there were no significant differences in systolic and diastolic blood pressures decreases, plasma fasting blood glucose and HbA1c between the 2 groups. Compared with amlodipine group, fasting blood insulin levels and insulin resistance index (HOMA-IR) were significantly decreased in losartan group, and in addition, the circulating levels of 8-OHdG and NT were significantly decreased in losartan group, while the serum SOD activity was enhanced. There were significant positively correlations of HOMA-IR with inflammatory oxidative stress markers. In vitro study showed that losartan could increase glucose uptake in 3T3-L1 adipocytes (Padipocyte size (Preduction of oxidative stress and inflammation in patients with type 2 DKD as well as the activation of insulin signal pathway in insulin-resistance 3T3-L1 adipocytes through
Full Text Available Peroxiredoxins (Prxs are ubiquitous thiol peroxidases that are involved in the reduction of peroxides. It has been reported that prokaryotic Prxs generally show greater structural robustness than their eukaryotic counterparts, making them less prone to inactivation by overoxidation. This difference has inspired the search for new antioxidants from prokaryotic sources that can be used as possible therapeutic biodrugs. Bacterioferritin comigratory proteins (Bcps of the hyperthermophilic archaeon Sulfolobus solfataricus that belong to the Prx family have recently been characterized. One of these proteins, Bcp1, was chosen to determine its antioxidant effects in H9c2 rat cardiomyoblast cells. Bcp1 activity was measured in vitro under physiological temperature and pH conditions that are typical of mammalian cells; the yeast thioredoxin reductase (yTrxR/thioredoxin (yTrx reducing system was used to evaluate enzyme activity. A TAT-Bcp1 fusion protein was constructed to allow its internalization and verify the effect of Bcp1 on H9c2 rat cardiomyoblasts subjected to oxidative stress. The results reveal that TAT-Bcp1 is not cytotoxic and inhibits H2O2-induced apoptosis in H9c2 cells by reducing the H2O2 content inside these cells.
Full Text Available To establish the effect of low (11 mM and high (55 mM glucose concentrations (G11, G55 on Jurkat cells exposed to rotenone (ROT, a class 5 mitocan. We demonstrated that ROT induces apoptosis in Jurkat cells cultured in G11 by oxidative stress (OS mechanism involving the generation of anion superoxide radical (O2∙-, 68%/hydrogen peroxide (H2O2, 54%, activation of NF-κB (32%, p53 (25%, c-Jun (17% transcription factors, and caspase-3 (28%, apoptosis-inducing factor (AIF, 36% nuclei translocation, c-Jun N-terminal kinase (JNK activation, and loss of mitochondria transmembrane potential (ΔΨm, 62% leading to nuclei fragmentation (~10% and ~40% stage I-II fragmented nuclei, resp.. ROT induces massive cytoplasmic aggregates of DJ-1 (93%, and upregulation of Parkin compared to untreated cells, but no effect on PINK-1 protein was observed. Cell death marker detection and DJ-1 and Parkin expression were significantly reduced when cells were cultured in G55 plus ROT. Remarkably, metformin sensitized Jurkat cells against ROT in G55. Our results indicate that a high-glucose milieu promotes resistance against ROT/H2O2-induced apoptosis in Jurkat cells. Our data suggest that combined therapy by using mitochondria-targeted damaging compounds and regulation of glucose (e.g., metformin can efficiently terminate leukemia cells via apoptosis in hyperglycemic conditions.
Ko, Ji-Ae; Sotani, Yasuyuki; Ibrahim, Diah Gemala; Kiuchi, Yoshiaki
Proliferative vitreoretinopathy (PVR) is the major cause of treatment failure in individuals who undergo surgery for retinal detachment. The epithelial-mesenchymal transition (EMT) in retinal pigment epithelium (RPE) cells contributes to the pathogenesis of PVR. Oxidative stress is thought to play a role in the progression of retinal diseases including PVR. We have now examined the effects of oxidative stress on the EMT and related processes in the human RPE cell line. We found that H 2 O 2 induced the contraction of RPE cells in a three-dimensional collagen gel. Analysis of a cytokine array revealed that H 2 O 2 specifically increased the release of macrophage migration inhibitory factor (MIF) from RPE cells. Reverse transcription-polymerase chain reaction and immunoblot analyses showed that H 2 O 2 increased the expression of MIF in RPE cells. Immunoblot and immunofluorescence analyses revealed that H 2 O 2 upregulated the expression of α-SMA and vimentin and downregulated that of ZO-1 and N-cadherin. Consistent with these observations, the transepithelial electrical resistance of cell was reduced by exposure to H 2 O 2 . The effects of oxidative stress on EMT-related and junctional protein expression as well as on transepithelial electrical resistance were inhibited by antibodies to MIF, but they were not mimicked by treatment with recombinant MIF. Finally, analysis with a profiling array for mitogen-activated protein kinase signalling revealed that H 2 O 2 specifically induced the phosphorylation of p38 mitogen-activated protein kinase. Our results thus suggest that MIF may play a role in induction of the EMT and related processes by oxidative stress in RPE cells and that it might thereby contribute to the pathogenesis of PVR. Proliferative vitreoretinopathy is a major complication of rhegmatogenous retinal detachment, and both oxidative stress and induction of the EMT in RPE cells are thought to contribute to the pathogenesis of this condition. We have now
. Further, knocking down CREB expression by siRNA resulted in significant suppression of IL-32 induction by IFNγ and H2O2 in HBE cells. Conclusion IL-32 expression in airway epithelium may be augmented by inflammation and oxidative stress, which may occur in COPD acute exacerbation. c-Jun and CREB are key transcriptional factors in IFNγ and H2O2 induced IL-32 expression. PMID:22413812
Full Text Available Creatine (Cr is naturally produced in the body and stored in muscles where it is involved in energy generation. It is widely used, especially by athletes, as a staple supplement for improving physical performance. Recent reports have shown that Cr displays antioxidant activity which could explain its beneficial cellular effects. We have evaluated the ability of Cr to protect human erythrocytes and lymphocytes against oxidative damage. Erythrocytes were challenged with model oxidants, 2, 2'-azobis(2-amidinopropane dihydrochloride (AAPH and hydrogen peroxide (H2O2 in the presence and absence of Cr. Incubation of erythrocytes with oxidant alone increased hemolysis, methemoglobin levels, lipid peroxidation and protein carbonyl content. This was accompanied by decrease in glutathione levels. Antioxidant enzymes and antioxidant power of the cell were compromised while the activity of membrane bound enzyme was lowered. This suggests induction of oxidative stress in erythrocytes by AAPH and H2O2. However, Cr protected the erythrocytes by ameliorating the AAPH and H2O2 induced changes in these parameters. This protective effect was confirmed by electron microscopic analysis which showed that oxidant-induced cell damage was attenuated by Cr. No cellular alterations were induced by Cr alone even at 20 mM, the highest concentration used. Creatinine, a by-product of Cr metabolism, was also shown to exert protective effects, although it was slightly less effective than Cr. Human lymphocytes were similarly treated with H2O2 in absence and presence of different concentrations of Cr. Lymphocytes incubated with oxidant alone had alterations in various biochemical and antioxidant parameters including decrease in cell viability and induction of DNA damage. The presence of Cr attenuated all these H2O2-induced changes in lymphocytes. Thus, Cr can function as a blood antioxidant, protecting cells from oxidative damage, genotoxicity and can potentially increase their
Boonekamp, Jelle J.; Bauch, Christina; Mulder, Ellis; Verhulst, Simon
Oxidative stress shortens telomeres in cell culture, but whether oxidative stress explains variation in telomere shortening in vivo at physiological oxidative stress levels is not well known. We therefore tested for correlations between six oxidative stress markers and telomere attrition in nestling
Zhong, Shi-Ying; Chen, Yong-Xing; Fang, Min; Zhu, Xiao-Long; Zhao, Yan-Xin; Liu, Xue-Yuan
This study aimed to investigate the influence of low-dose levodopa (L-DOPA) on neuronal cell death under oxidative stress. PC12 cells were treated with L-DOPA at different concentrations. We detected the L-DOPA induced reactive oxygen species (ROS). Meanwhile, MTT and LDH assay were performed to determine the proliferation and growth of PC12 cells with or without ROS scavenger. In addition, after pretreatment with L-DOPA at different concentrations alone or in combination with CD39 inhibitor, PC12 cells were incubated with hydrogen peroxide (H2O2) and the cell viability was evaluated by MTT and LDH assay. In addition, the expression of pCREB and CD39 was detected by immunofluorescence staining and Western blot assay in both cells and rat's brain after L-DOPA treatment. After treatment with L-DOPA for 3 days, the cell proliferation and growth were promoted when the L-DOPA concentration was 30 µM. Low dose L-DOPA could protect the PC12 cells from H2O2 induced oxidative stress, which was compromised by CD39 inhibitor. In addition, the expression of CD39 and pCREB increased in both PC12 cells and rats' brain after L-DOPA treatment. L-DOPA at different concentrations has distinct influence on proliferation and growth of PC12 cells, and low dose (<30 µM) L-DOPA protects PC12 cells against oxidative stress which might be related to the up-regulation of CD39 and pCREB expression.
Full Text Available OBJECTIVE: This study aimed to investigate the influence of low-dose levodopa (L-DOPA on neuronal cell death under oxidative stress. METHODS: PC12 cells were treated with L-DOPA at different concentrations. We detected the L-DOPA induced reactive oxygen species (ROS. Meanwhile, MTT and LDH assay were performed to determine the proliferation and growth of PC12 cells with or without ROS scavenger. In addition, after pretreatment with L-DOPA at different concentrations alone or in combination with CD39 inhibitor, PC12 cells were incubated with hydrogen peroxide (H2O2 and the cell viability was evaluated by MTT and LDH assay. In addition, the expression of pCREB and CD39 was detected by immunofluorescence staining and Western blot assay in both cells and rat's brain after L-DOPA treatment. RESULTS: After treatment with L-DOPA for 3 days, the cell proliferation and growth were promoted when the L-DOPA concentration was 30 µM. Low dose L-DOPA could protect the PC12 cells from H2O2 induced oxidative stress, which was compromised by CD39 inhibitor. In addition, the expression of CD39 and pCREB increased in both PC12 cells and rats' brain after L-DOPA treatment. CONCLUSIONS: L-DOPA at different concentrations has distinct influence on proliferation and growth of PC12 cells, and low dose (<30 µM L-DOPA protects PC12 cells against oxidative stress which might be related to the up-regulation of CD39 and pCREB expression.
King, Shelby M; Quartuccio, Suzanne M; Vanderhyden, Barbara C; Burdette, Joanna E
Ovarian cancer is the deadliest gynecological malignancy due to detection of cancer at a late stage when the disease has metastasized. One likely progenitor cell type of ovarian cancer is the ovarian surface epithelium (OSE), which proliferates rapidly in the presence of inflammatory cytokines and oxidative stress following ovulation. To determine whether oxidative stress induces DNA damage leading to spontaneous transformative changes in normal OSE, an immortalized mouse OSE cell line (MOSE cells) or normal mouse ovarian organoids were treated with hydrogen peroxide (H2O2) and loss of contact inhibition was assessed by soft agar assay. In response to H2O2, OSE cells grown in 3D exhibited growth in soft agar but MOSE cells grown on 2D plastic did not, indicating a critical role for epithelial-stromal interactions in neoplastic initiation. Loss of contact inhibition in response to H2O2 correlated with an increase in proliferation, DNA damage and upregulation of the oncogene Akt1. Use of a reactive oxygen species scavenger or Akt inhibitor blocked H2O2-induced proliferation and growth in soft agar. Although parental MOSE cells did not undergo transformation by H2O2, MOSE cells stably overexpressing constitutively active myristoylated Akt or knockdown of phosphatase and tensin homolog (PTEN) exhibited loss of contact inhibition and increased proliferation. This study indicates that normal OSE undergo transformative changes induced by oxidative stress and that this process requires Akt upregulation and activation. A 3D model that retains tissue architecture is critical for studying this process and may lead to development of new intervention strategies directed at early stages of ovarian cancer.
Full Text Available Oxidative stress is implicated in the pathogenesis of pancreatic β-cell dysfunction that occurs in both type 1 and type 2 diabetes. Nuclear factor E2-related factor 2 (NRF2 is a master regulator in the cellular adaptive response to oxidative stress. The present study found that MIN6 β-cells with stable knockdown of Nrf2 (Nrf2-KD and islets isolated from Nrf2-knockout mice expressed substantially reduced levels of antioxidant enzymes in response to a variety of stressors. In scramble MIN6 cells or wild-type islets, acute exposure to oxidative stressors, including hydrogen peroxide (H2O2 and S-nitroso-N-acetylpenicillamine, resulted in cell damage as determined by decrease in cell viability, reduced ATP content, morphology changes of islets, and/or alterations of apoptotic biomarkers in a concentration- and/or time-dependent manner. In contrast, silencing of Nrf2 sensitized MIN6 cells or islets to the damage. In addition, pretreatment of MIN6 β-cells with NRF2 activators, including CDDO-Im, dimethyl fumarate (DMF, and tert-butylhydroquinone (tBHQ, protected the cells from high levels of H2O2-induced cell damage. Given that reactive oxygen species (ROS are involved in regulating glucose-stimulated insulin secretion (GSIS and persistent activation of NRF2 blunts glucose-triggered ROS signaling and GSIS, the present study highlights the distinct roles that NRF2 may play in pancreatic β-cell dysfunction that occurs in different stages of diabetes.
Zhang, Lan; Sun, Shuming; Zhou, Jie; Liu, Jiao; Lv, Jia-Han; Yu, Xiang-Qiang; Li, Chi; Gong, Lili; Yan, Qin; Deng, Mi; Xiao, Ling; Ma, Haili; Liu, Jin-Ping; Peng, Yun-Lei; Wang, Dao; Liao, Gao-Peng; Zou, Li-Jun; Liu, Wen-Bin; Xiao, Ya-Mei
Abstract The Akt signaling pathway plays a key role in promoting the survival of various types of cells from stress-induced apoptosis, and different members of the Akt family display distinct physiological roles. Previous studies have shown that in response to UV irradiation, Akt2 is sensitized to counteract the induced apoptosis. However, in response to oxidative stress such as hydrogen peroxide, it remains to be elucidated what member of the Akt family would be activated to initiate the signaling cascades leading to resistance of the induced apoptosis. In the present study, we present the first evidence that knockdown of Akt1 enhances cell survival under exposure to 50 μM H2O2. This survival is derived from selective upregulation and activation of Akt2 but not Akt3, which initiates 3 major signaling cascades. First, murine double minute 2 (MDM2) is hyperphosphorylated, which promotes p53 degradation and attenuates its Ser-15 phosphorylation, significantly attenuating Bcl-2 homologous antagonist killer (Bak) upregulation. Second, Akt2 activation inactivates glycogen synthase kinase 3 beta (GSK-3β) to promote stability of myeloid leukemia cell differentiation protein 1 (MCL-1). Finally, Akt2 activation promotes phosphorylation of FOXO3A toward cytosolic export and thus downregulates Bim expression. Overexpression of Bim enhances H2O2-induced apoptosis. Together, our results demonstrate that among the Akt family members, Akt2 is an essential kinase in counteracting oxidative-stress-induced apoptosis through multiple signaling pathways. Antioxid. Redox Signal. 15, 1–17. PMID:21303257
Tan, Jun Jie; Azmi, Siti Maisura; Yong, Yoke Keong; Cheah, Hong Leong; Lim, Vuanghao; Sandai, Doblin; Shaharuddin, Bakiah
Stem cells with enhanced resistance to oxidative stress after in vitro expansion have been shown to have improved engraftment and regenerative capacities. Such cells can be generated by preconditioning them with exposure to an antioxidant. In this study we evaluated the effects of Tualang honey (TH), an antioxidant-containing honey, on human corneal epithelial progenitor (HCEP) cells in culture. Cytotoxicity, gene expression, migration, and cellular resistance to oxidative stress were evaluated. Immunofluorescence staining revealed that HCEP cells were holoclonal and expressed epithelial stem cell marker p63 without corneal cytokeratin 3. Cell viability remained unchanged after cells were cultured with 0.004, 0.04, and 0.4% TH in the medium, but it was significantly reduced when the concentration was increased to 3.33%. Cell migration, tested using scratch migration assay, was significantly enhanced when cells were cultured with TH at 0.04% and 0.4%. We also found that TH has hydrogen peroxide (H2O2) scavenging ability, although a trace level of H2O2 was detected in the honey in its native form. Preconditioning HCEP cells with 0.4% TH for 48 h showed better survival following H2O2-induced oxidative stress at 50 µM than untreated group, with a significantly lower number of dead cells (15.3±0.4%) were observed compared to the untreated population (20.5±0.9%, p<0.01). Both TH and ascorbic acid improved HCEP viability following induction of 100 µM H2O2, but the benefit was greater with TH treatment than with ascorbic acid. However, no significant advantage was demonstrated using 5-hydroxymethyl-2-furancarboxaldehyde, a compound that was found abundant in TH using GC/MS analysis. This suggests that the cellular anti-oxidative capacity in HCEP cells was augmented by native TH and was attributed to its antioxidant properties. In conclusion, TH possesses antioxidant properties and can improve cell migration and cellular resistance to oxidative stress in HCEP cells in
Bhatti, F U; Mehmood, A; Latief, N; Zahra, S; Cho, H; Khan, S N; Riazuddin, S
Oxidative stress is a major obstacle against cartilage repair in osteoarthritis (OA). Anti-oxidant agents can play a vital role in addressing this issue. We evaluated the effect of Vitamin E preconditioning in improving the potential of mesenchymal stem cells (MSCs) to confer resistance against oxidative stress prevailing during OA. Vitamin E pretreated MSCs were exposed to oxidative stress in vitro by hydrogen peroxide (H 2 O 2 ) and also implanted in surgically-induced rat model of OA. Analysis was done in terms of cell proliferation, apoptosis, cytotoxicity, chondrogenesis and repair of cartilage tissue. Vitamin E pretreatment enabled MSCs to counteract H 2 O 2 -induced oxidative stress in vitro. Proliferative markers, proliferating cell nuclear antigen (PCNA) and Ki67 were up-regulated, along with the increase in the viability of MSCs. Expression of transforming growth factor-beta (TGFβ) was also increased. Reduction of apoptosis, expression of vascular endothelial growth factor (VEGF) and caspase 3 (Casp3) genes, and lactate dehydrogenase (LDH) release were also observed. Transplantation of Vitamin E pretreated MSCs resulted in increased proteoglycan contents of cartilage matrix. Increased expression of chondrogenic markers, Aggrecan (Acan) and collagen type-II alpha (Col2a1) accompanied by decreased expression of collagen type-I alpha (Col1a1) resulted in increased differentiation index that signifies the formation of hyaline cartilage. Further, there was an increased expression of PCNA and TGFβ genes along with a decreased expression of Casp3 and VEGF genes with increased histological score. Taken together results of this study demonstrated that Vitamin E pretreated MSCs have an improved ability to impede the progression of OA and thus increased potential to treat OA. Copyright © 2016 Osteoarthritis Research Society International. All rights reserved.
Full Text Available BACKGROUND: To investigate if microRNAs (miRNAs play a role in regulating h-ERG trafficking in the setting of chronic oxidative stress as a common deleterious factor for many cardiac disorders. METHODS: We treated neonatal rat ventricular myocytes and HEK293 cells with stable expression of h-ERG with H2O2 for 12 h and 48 h. Expression of miR-17-5p seed miRNAs was quantified by real-time RT-PCR. Protein levels of chaperones and h-ERG trafficking were measured by Western blot analysis. Luciferase reporter gene assay was used to study miRNA and target interactions. Whole-cell patch-clamp techniques were employed to record h-ERG K(+ current. RESULTS: H-ERG trafficking was impaired by H2O2 after 48 h treatment, accompanied by reciprocal changes of expression between miR-17-5p seed miRNAs and several chaperones (Hsp70, Hsc70, CANX, and Golga2, with the former upregulated and the latter downregulated. We established these chaperones as targets for miR-17-5p. Application miR-17-5p inhibitor rescued H2O2-induced impairment of h-ERG trafficking. Upregulation of endogenous by H2O2 or forced miR-17-5p expression either reduced h-ERG current. Sequestration of AP1 by its decoy molecule eliminated the upregulation of miR-17-5p, and ameliorated impairment of h-ERG trafficking. CONCLUSIONS: Collectively, deregulation of the miR-17-5p seed family miRNAs can cause severe impairment of h-ERG trafficking through targeting multiple ER stress-related chaperones, and activation of AP1 likely accounts for the deleterious upregulation of these miRNAs, in the setting of prolonged duration of oxidative stress. These findings revealed the role of miRNAs in h-ERG trafficking, which may contribute to the cardiac electrical disturbances associated with oxidative stress.
Li, Hongbo; Wang, Baoying; Zhu, Chunhui; Feng, Yan; Wang, Shaolan; Shahzad, Muhammad; Hu, Chenghu; Mo, Mingshu; Du, Fangying; Yu, Xiaorui
Oxidative stress leading to retinal nerve cells (RNCs) apoptosis is a major cause of neurodegenerative disorders of the retina. 17β-Estradiol (E2) has been suggested to be a neuroprotective agent in the central nervous system; however, at present, the underlying mechanisms are not well understood, and the related research on the RNCs is less reported. Here, in order to investigate the protective role and mechanism of E2 against oxidative stress-induced damage on RNCs, the transmission electron microscopy and annexin V-FITC/propidium iodide assay were applied to detect the RNCs apoptosis. Western blot and real-time PCR were used to determine the expression of the critical molecules in Bcl-2 and caspase family associated with apoptosis. The transmission electron microscopy results showed that H(2)O(2) could induce typical features of apoptosis in RNCs, including formation of the apoptosome. E2 could, however, suppress the H(2)O(2)-induced morphological changes of apoptosis. Intriguingly, we observed E2-mediated phagocytic scavenging of apoptosome. In response to H(2)O(2)-induced apoptosis, Bax, acting as one of the pivotal pro-apoptotic members of Bcl-2 family, increased significantly, which directly resulted in an increased ratio of Bax to anti-apoptotic protein Bcl-2 (Bax/Bcl-2). Additionally, caspases 9 and 3, which are the critical molecules of the mitochondrial apoptosis pathway, were activated by H(2)O(2). In contrast, E2 exerted anti-apoptotic effects by reducing the expression of Bax to decrease the ratio of Bax/Bcl-2 and impeded the caspases 9/3 activation. Moreover, LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor, could sharply block the effect of E2 in reducing the percentage of apoptotic cells resistance to H(2)O(2). And the attenuation of Bax, the reduced activities of caspases 9/3 and the impeded release of mitochondrial cytochrome c mediated by E2 resistance to H(2)O(2) damage were significantly retrieved by LY294002 administration. Taken
Lee, Sang C; Zhang, Jack; Strom, Josh; Yang, Danzhou; Dinh, Thai Nho; Kappeler, Kyle; Chen, Qin M
Inhibition of protein synthesis serves as a general measure of cellular consequences of chemical stress. A few proteins are translated selectively and influence cell fate. How these proteins can bypass the general control of translation remains unknown. We found that low to mild doses of oxidants induce de novo translation of the NRF2 protein. Here we demonstrate the presence of a G-quadruplex structure in the 5' untranslated region (UTR) of NRF2 mRNA, as measured by circular dichroism, nuclear magnetic resonance, and dimethylsulfate footprinting analyses. Such a structure is important for 5'-UTR activity, since its removal by sequence mutation eliminated H2O2-induced activation of the NRF2 5' UTR. Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomics revealed elongation factor 1 alpha (EF1a) as a protein binding to the G-quadruplex sequence. Cells responded to H2O2 treatment by increasing the EF1a protein association with NRF2 mRNA, as measured by RNA-protein interaction assays. The EF1a interaction with small and large subunits of ribosomes did not appear to change due to H2O2 treatment, nor did posttranslational modifications, as measured by two-dimensional (2-D) Western blot analysis. Since NRF2 encodes a transcription factor essential for protection against tissue injury, our data have revealed a novel mechanism of cellular defense involving de novo NRF2 protein translation governed by the EF1a interaction with the G-quadruplex in the NRF2 5' UTR during oxidative stress. Copyright © 2016 American Society for Microbiology.
Kristi M Porter
Full Text Available Pulmonary Hypertension (PH is a progressive disorder characterized by endothelial dysfunction and proliferation. Hypoxia induces PH by increasing vascular remodeling. A potential mediator in hypoxia-induced PH development is arachidonate 5-Lipoxygenase (ALOX5. While ALOX5 metabolites have been shown to promote pulmonary vasoconstriction and endothelial cell proliferation, the contribution of ALOX5 to hypoxia-induced proliferation remains unknown. We hypothesize that hypoxia exposure stimulates HPAEC proliferation by increasing ALOX5 expression and activity. To test this, human pulmonary artery endothelial cells (HPAEC were cultured under normoxic (21% O2 or hypoxic (1% O2 conditions for 24-, 48-, or 72 hours. In a subset of cells, the ALOX5 inhibitor, zileuton, or the 5-lipoxygenase activating protein inhibitor, MK-886, was administered during hypoxia exposure. ALOX5 expression was measured by qRT-PCR and western blot and HPAEC proliferation was assessed. Our results demonstrate that 24 and 48 hours of hypoxia exposure have no effect on HPAEC proliferation or ALOX5 expression. Seventy two hours of hypoxia significantly increases HPAEC ALOX5 expression, hydrogen peroxide (H2O2 release, and HPAEC proliferation. We also demonstrate that targeted ALOX5 gene silencing or inhibition of the ALOX5 pathway by pharmacological blockade attenuates hypoxia-induced HPAEC proliferation. Furthermore, our findings indicate that hypoxia-induced increases in cell proliferation and ALOX5 expression are dependent on H2O2 production, as administration of the antioxidant PEG-catalase blocks these effects and addition of H2O2 to HPAEC promotes proliferation. Overall, these studies indicate that hypoxia exposure induces HPAEC proliferation by activating the ALOX5 pathway via the generation of H2O2.
digestion occurs at matrix attachment regions (MARs), and proceeds in distinct, spatio-temporal stages (figure. 1). The, as yet unidentified, MAR-associated endonu- clease works through a single strand scission mechanism. (Walker et al 1997). Thus, the enzyme initially cuts only one DNA strand; while a second, closely ...
Francisco, Bosch-Morell; Salvador, Mérida; Amparo, Navea
Myopia affected approximately 1.6 billion people worldwide in 2000, and it is expected to increase to 2.5 billion by 2020. Although optical problems can be corrected by optics or surgical procedures, normal myopia and high myopia are still an unsolved medical problem. They frequently predispose people who have them to suffer from other eye pathologies: retinal detachment, glaucoma, macular hemorrhage, cataracts, and so on being one of the main causes of visual deterioration and blindness. Genetic and environmental factors have been associated with myopia. Nevertheless, lack of knowledge in the underlying physiopathological molecular mechanisms has not permitted an adequate diagnosis, prevention, or treatment to be found. Nowadays several pieces of evidence indicate that oxidative stress may help explain the altered regulatory pathways in myopia and the appearance of associated eye diseases. On the one hand, oxidative damage associated with hypoxia myopic can alter the neuromodulation that nitric oxide and dopamine have in eye growth. On the other hand, radical superoxide or peroxynitrite production damage retina, vitreous, lens, and so on contributing to the appearance of retinopathies, retinal detachment, cataracts and so on. The objective of this review is to suggest that oxidative stress is one of the key pieces that can help solve this complex eye problem. PMID:25922643
The effect of Sunphenon and Polyphenon 60 in oxidative stress response, myogenic regulatory factors, inflammatory cytokines, apoptotic and proteolytic pathways on H2O2-induced myotube atrophy was addressed. Cellular responses of H2O2-induced C2C12cells were examined, including mRNA expression of myogenic ...
Song, Jia-Le; Choi, Jung-Ho; Seo, Jae-Hoon; Kil, Jeung-Ha
BACKGROUND/OBJECTIVES This study was performed to investigate the in vitro antioxidant and cytoprotective effects of fermented sesame sauce (FSeS) against hydrogen peroxide (H2O2)-induced oxidative damage in renal proximal tubule LLC-PK1 cells. MATERIALS/METHODS 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (•OH), and H2O2 scavenging assay was used to evaluate the in vitro antioxidant activity of FSeS. To investigate the cytoprotective effect of FSeS against H2O2-induced oxidative damage in LLC-PK1 cells, the cellular levels of reactive oxygen species (ROS), lipid peroxidation, and endogenous antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-px) were measured. RESULTS The ability of FSeS to scavenge DPPH, •OH and H2O2 was greater than that of FSS and AHSS. FSeS also significantly inhibited H2O2-induced (500 µM) oxidative damage in the LLC-PK1 cells compared to FSS and AHSS (P sauces, FSeS also significantly increased cellular CAT, SOD, and GSH-px activities and mRNA expression (P < 0.05). CONCULUSIONS These results from the present study suggest that FSeS is an effective radical scavenger and protects against H2O2-induced oxidative damage in LLC-PK1 cells by reducing ROS levels, inhibiting lipid peroxidation, and stimulating antioxidant enzyme activity. PMID:24741396
Full Text Available Abstract Background Excessive oxidative stress and lipid peroxidation have been demonstrated to play important roles in the production of liver damage. L-carnitine is a natural substance and acts as a carrier for fatty acids across the inner mitochondrial membrane for subsequent beta-oxidation. It is also an antioxidant that reduces metabolic stress in the cells. Recent years L-carnitine has been proposed for treatment of various kinds of disease, including liver injury. This study was conducted to evaluate the protective effect of L-carnitine against hydrogen peroxide (H2O2-induced cytotoxicity in a normal human hepatocyte cell line, HL7702. Methods We analyzed cytotoxicity using MTT assay and lactate dehydrogenase (LDH release. Antioxidant activity and lipid peroxidation were estimated by reactive oxygen species (ROS levels, activities and protein expressions of superoxide dismutase (SOD and catalase (CAT, and malondialdehyde (MDA formation. Expressions of peroxisome proliferator-activated receptor (PPAR-alpha and its target genes were evaluated by RT-PCR or western blotting. The role of PPAR-alpha in L-carnitine-enhanced expression of SOD and CAT was also explored. Statistical analysis was performed by a one-way analysis of variance, and its significance was assessed by Dennett's post-hoc test. Results The results showed that L-carnitine protected HL7702 cells against cytotoxity induced by H2O2. This protection was related to the scavenging of ROS, the promotion of SOD and CAT activity and expression, and the prevention of lipid peroxidation in cultured HL7702 cells. The decreased expressions of PPAR-alpha, carnitine palmitoyl transferase 1 (CPT1 and acyl-CoA oxidase (ACOX induced by H2O2 can be attenuated by L-carnitine. Besides, we also found that the promotion of SOD and CAT protein expression induced by L-carnitine was blocked by PPAR-alpha inhibitor MK886. Conclusions Taken together, our findings suggest that L-carnitine could protect HL
Background Excessive oxidative stress and lipid peroxidation have been demonstrated to play important roles in the production of liver damage. L-carnitine is a natural substance and acts as a carrier for fatty acids across the inner mitochondrial membrane for subsequent beta-oxidation. It is also an antioxidant that reduces metabolic stress in the cells. Recent years L-carnitine has been proposed for treatment of various kinds of disease, including liver injury. This study was conducted to evaluate the protective effect of L-carnitine against hydrogen peroxide (H2O2)-induced cytotoxicity in a normal human hepatocyte cell line, HL7702. Methods We analyzed cytotoxicity using MTT assay and lactate dehydrogenase (LDH) release. Antioxidant activity and lipid peroxidation were estimated by reactive oxygen species (ROS) levels, activities and protein expressions of superoxide dismutase (SOD) and catalase (CAT), and malondialdehyde (MDA) formation. Expressions of peroxisome proliferator-activated receptor (PPAR)-alpha and its target genes were evaluated by RT-PCR or western blotting. The role of PPAR-alpha in L-carnitine-enhanced expression of SOD and CAT was also explored. Statistical analysis was performed by a one-way analysis of variance, and its significance was assessed by Dennett's post-hoc test. Results The results showed that L-carnitine protected HL7702 cells against cytotoxity induced by H2O2. This protection was related to the scavenging of ROS, the promotion of SOD and CAT activity and expression, and the prevention of lipid peroxidation in cultured HL7702 cells. The decreased expressions of PPAR-alpha, carnitine palmitoyl transferase 1 (CPT1) and acyl-CoA oxidase (ACOX) induced by H2O2 can be attenuated by L-carnitine. Besides, we also found that the promotion of SOD and CAT protein expression induced by L-carnitine was blocked by PPAR-alpha inhibitor MK886. Conclusions Taken together, our findings suggest that L-carnitine could protect HL7702 cells against
Wang, Yu; Wang, Yi-Li; Huang, Xia; Yang, Yang; Zhao, Ya-Jun; Wei, Cheng-Xi; Zhao, Ming
Atrial fibrillation (AF) is a complex disease with multiple inter-relating causes culminating in rapid atrial activation and atrial structural remodeling. The contribution of endoplasmic reticulum and mitochondria stress to AF has been highlighted. As the class III antiarrhythmic agent, ibutilide are widely used to AF. This study was designed to explore whether ibutilide could treat AF by inhibiting endoplasmic reticulum stress pathways and mitochondria stress. The neonatal rat cardiomyocytes were isolated and exposed to H2O2, ibutilide was add to the culture medium 12 h. Then the cell viability, oxidative stress levels and apoptotic rate were analyzed. In addition, endoplasmic reticulum stress related protein (GRP78, GRP94, CHOP), mitochondria-dependent protein (Bax, Bcl-2) and caspase-3/9/12 were identified by real-time PCR and western blot analysis. In our results, remarkable decreased cell viability and oxidative stress levels were detected in cardiomyocytes after treating with H2O2. The apoptotic rate and the expression of proteins involved in mitochondrial stress and endoplasmic reticulum stress pathways increased. While ibutilide significantly inhibited these changes. These data suggested that ibutilide serves a protective role against H2O2-induced apoptosis of neonatal rat cardiomyocytes, and the mechanism is related to suppression of mitochondrial stress and endoplasmic reticulum stress.
Spasov, A A; Zheltova, A A; Kharitonov, M V
Magnesium deficiency has been shown to result in alterations of cellular functions and biological activity of molecules. The review discusses possible relationship between Mg2+ deficiency and development of oxidative stress. Decrease of Mg2+ concentration in tissues and blood is accompanied with elevation of the oxidative stress markers, including products of the oxidative modification of lipids, proteins and DNA. The reduction in antioxidant defenses is synchronous with oxidative stress markers elevation. Different mechanisms including systemic reactions (hyperactivation of inflammation and endothelial dysfunction) and cellular changes (mitochondrial dysfunction and excessive production of fatty acids) are supposed to be involved in development and maintenance of the oxidative stress due to Mg2+ deficiency. Therefore the facts consolidated into the review evidence clear relation between Mg2+ deficiency and the oxidative stress development.
Ramirez, Dario C; Gomez Mejiba, Sandra E; Mason, Ronald P
We have reinvestigated the biochemistry of H2O2-induced Cu,Zn-superoxide dismutase (SOD1)-centered radicals, detecting them by immuno-spin trapping. These radicals are involved in H2O2-induced structural and functional damage to SOD1, and their mechanism of generation depends on copper and/or (bi)carbonate (i.e., CO2, CO3(-2), or HCO3-). First, in the absence of DTPA and (bi)carbonate, Cu(II) was partially released and rebound at His, Cys, and Tyr residues in SOD1 with the generation of protein-copper-bound oxidants outside the SOD1 active site by reaction with excess H2O2. These species produced immuno-spin trapping-detectable SOD1-centered radicals associated with H2O2-induced active site ( approximately 5 and approximately 10 kDa fragments) and non-active site (smearing between 3 and 16 kDa) copper-dependent backbone oxidations and subsequent fragmentation of SOD1. Second, in the presence of DTPA, which inhibits H2O2-induced SOD1 non-active site fragmentation, (bi)carbonate scavenged the enzyme-bound oxidant at the SOD1 active site to produce the carbonate radical anion, CO3*-, thus protecting against active site SOD1 fragmentation. CO3*- diffuses and produces side chain oxidations forming DMPO-trappable radical sites outside the enzyme active site. Both mechanisms for generating immuno-spin trapping-detectable SOD1-centered radicals were susceptible to inhibition by cyanide and enhanced at high pH values. In addition, (bi)carbonate enhanced H2O2-induced SOD1 turnover as demonstrated by an enhancement in oxygen evolution and SOD1 inactivation. These results help clarify the free radical chemistry involved in the functional and structural oxidative damage to SOD1 by H2O2 with the intermediacy of copper- and CO3*--mediated oxidations.
Yong Weon Yi
Full Text Available The breast cancer susceptibility gene 1 (BRCA1 has been well established as a tumor suppressor and functions primarily by maintaining genome integrity. Genome stability is compromised when cells are exposed to oxidative stress. Increasing evidence suggests that BRCA1 regulates oxidative stress and this may be another mechanism in preventing carcinogenesis in normal cells. Oxidative stress caused by reactive oxygen species (ROS is implicated in carcinogenesis and is used strategically to treat human cancer. Thus, it is essential to understand the function of BRCA1 in oxidative stress regulation. In this review, we briefly summarize BRCA1’s many binding partners and mechanisms, and discuss data supporting the function of BRCA1 in oxidative stress regulation. Finally, we consider its significance in prevention and/or treatment of BRCA1-related cancers.
Krishnamurthy, Aparna; Rathinasabapathi, Bala
Biotic and abiotic stress conditions produce reactive oxygen species (ROS) in plants causing oxidative stress damage. At the same time, ROS have additional signaling roles in plant adaptation to the stress. It is not known how the two seemingly contrasting functional roles of ROS between oxidative damage to the cell and signaling for stress protection are balanced. Research suggests that the plant growth regulator auxin may be the connecting link regulating the level of ROS and directing its role in oxidative damage or signaling in plants under stress. The objective of this review is to highlight some of the recent research on how auxin’s role is intertwined to that of ROS, more specifically H2O2, in plant adaptation to oxidative stress conditions. PMID:23887492
Zhou, Xiangjun; Bai, Chen; Sun, Xinbo; Gong, Xiaoxin; Yang, Yong; Chen, Congbo; Shan, Guang; Yao, Qisheng
Puerarin (PR) is an isoflavonoid isolated from the root of the plant Pueraria lobata and has been widely used in traditional Chinese herbal medicine for the treatment of various diseases. Oxidative stress and epithelial cell apoptosis play important roles in the renal fibrotic process. The present study aimed to determine whether or not PR inhibits renal fibrosis by reducing oxidative stress induced-epithelial cell apoptosis. In vivo, unilateral ureteral obstruction (UUO) induced renal fibrosis, and epithelial cell apoptosis. A total of 24 mice were randomly assigned to four experimental groups: sham, UUO alone, UUO +50 mg/kg PR, and UUO +100 mg/kg PR. In vitro, 200 μM hydrogen peroxide (H2O2) induced epithelial cell apoptosis. The experiments were dived into four groups: control, H2O2 alone, H2O2+50 μM PR, and H2O2+100 μM PR. Tubular injury was measured in the renal cortex of the mice through periodic acid-Schiff (PAS) staining, and the extracellular matrix (ECM) was measured through Sirius red (SR), immunohistochemistry (IHC) staining, and Western blot. Renal epithelial cell apoptosis was measured through terminal deoxynucleotidyl transferase-mediated dUTP Nick-End labeling (TUNEL), flow cytometry (FCM), and Hoechst assays. The protein expression of NOX4, caspase3, ERK, P38, and JNK was assessed through Western blot. PAS staining showed that PR decreased renal tubular injury in UUO mice. SR and IHC staining demonstrated that PR decreased the accumulation of ECM. PR treatment significantly inhibited epithelial cell apoptosis according to the results of TUNEL, FCM, Hoechst, and Western blot. Furthermore, NOX4 increased in UUO mice and decreased with PR treatment. H2O2-derived oxidative stress activated epithelial apoptosis and mitogen-activated protein kinases (MAPK), and PR treatment significantly reversed it. These results suggest that PR treatment ameliorates renal fibrosis by inhibiting oxidative stress induced-epithelial cell apoptosis through
Girardot, Fabrice; Monnier, Véronique; Tricoire, Hervé
Background During their life, multicellular organisms are challenged with oxidative stress. It is generated by several reactive oxygen species (ROS), may limit lifespan and has been related to several human diseases. ROS can generate a wide variety of defects in many cellular components and thus the response of the organism challenged with oxidative stress may share some features with other stress responses. Conversely, in spite of recent progress, a complete functional analysis of the transcriptional responses to different oxidative stresses in model organisms is still missing. In addition, the functional significance of observed transcriptional changes is still elusive. Results We used oligonucleotide microarrays to address the specificities of transcriptional responses of adult Drosophila to different stresses induced by paraquat and H2O2, two oxidative stressors, and by tunicamycin which induces an endoplasmic reticulum (ER) stress. Both specific and common responses to the three stressors were observed and whole genome functional analysis identified several important classes of stress responsive genes. Within some functional classes, we observed that isozymes do not all behave similarly, which may reflect unsuspected functional specificities. Moreover, genetic experiments performed on a subset of lines bearing mutations in genes identified in microarray experiments showed that a significant number of these mutations may affect resistance of adult Drosophila to oxidative stress. Conclusions A long term common stress response to paraquat- or H2O2-induced oxidative stresses and ER stress is observed for a significant number of genes. Besides this common response, the unexpected complexity of the stress responses to oxidative and ER stresses in Drosophila, suggest significant specificities in protective properties between genes associated to the same functional classes. According to our functional analysis, a large part of the genome may play a role in protective
Gella, Alejandro; Durany, Nuria
Alzheimer disease (AD) is a progressive dementia affecting a large proportion of the aging population. The histopathological changes in AD include neuronal cell death, formation of amyloid plaques and neurofibrillary tangles. There is also evidence that brain tissue in patients with AD is exposed to oxidative stress (e.g., protein oxidation, lipid oxidation, DNA oxidation and glycoxidation) during the course of the disease. Advanced glycation endproducts (AGEs) are present in amyloid plaques ...
Li, Shuli; Zhu, Guannan; Yang, Yuqi; Jian, Zhe; Guo, Sen; Dai, Wei; Shi, Qiong; Ge, Rui; Ma, Jingjing; Liu, Ling; Li, Kai; Luan, Qi; Wang, Gang; Gao, Tianwen; Li, Chunying
In patients with vitiligo, an increased reactive oxygen species (ROS) level has been proved to be a key player during disease initiation and progression in melanocytes. Nevertheless, little is known about the effects of ROS on other cells involved in the aberrant microenvironment, such as keratinocytes and the following immune events. CXCL16 is constitutively expressed in keratinocytes and was recently found to mediate homing of CD8+ T cells in human skin. We sought to explicate the effect of oxidative stress on human keratinocytes and its capacity to drive CD8+ T-cell trafficking through CXCL16 regulation. We first detected putative T-cell skin-homing chemokines and ROS in serum and lesions of patients with vitiligo. The production of candidate chemokines was detected by using quantitative real-time PCR and ELISA in keratinocytes exposed to H2O2. Furthermore, the involved mediators were analyzed by using quantitative real-time PCR, Western blotting, ELISA, and immunofluorescence. Next, we tested the chemotactic migration of CD8+ T cells from patients with vitiligo mediated by the CXCL16-CXCR6 pair using the transwell assay. CXCL16 expression increased and showed a positive correlation with oxidative stress levels in serum and lesions of patients with vitiligo. The H2O2-induced CXCL16 expression was due to the activation of 2 unfolded protein response pathways: kinase RNA (PKR)-like ER kinase-eukaryotic initiation factor 2α and inositol-requiring enzyme 1α-X-box binding protein 1. CXCL16 produced by stressed keratinocytes induced migration of CXCR6+CD8+ T cells derived from patients with vitiligo. CXCR6+CD8+ T-cell skin infiltration is accompanied by melanocyte loss in lesions of patients with vitiligo. Our study demonstrated that CXCL16-CXCR6 mediates CD8+ T-cell skin trafficking under oxidative stress in patients with vitiligo. The CXCL16 expression in human keratinocytes induced by ROS is, at least in part, caused by unfolded protein response activation
Fernando Holguin; Anne Fitzpatrick
.... Contrary to what has previously been thought, the combination of obesity and asthma, both chronic inflammatory diseases, does not necessarily result in a synergistic effect, leading to even greater oxidative stress...
Ahsanuddin, Sayeeda; Lam, Minh; D. Baron, Elma
.... Here, we review the critical role that oxidative stress plays in skin aging, including its effects on signaling pathways involved in skin matrix formation and degradation, proteasome activity, as well as DNA structure...
Full Text Available Exercise appears to increase reactive oxygen species (ROS, which can result in damage to cells. Potential sources of ROS in skeletal muscle fibers during exercise include the mitochondrial respiratory chain, xantine oxidase production of superoxide, enzymatic arachidonic acid oxygenation, nitric oxide synthesis, catecholamine oxidation, and neutrophil-induced oxidative burts. Stress proteins (SPs represent one of the general molecular protective mechanisms that enable cell and whole organisms to survive stress. The exact relationship between exercise, ROS and SPs remains unclear. Antioxidant supplements have been touted by manufacturers as a means for athletes to perform better, recover more quickly and fully from endurance exercise, or allow them to train more strenuously. At present, data are insufficient to recommend antioxidant supplements for athletes or other persons who exercise regularly. However, no one questions the importance of ingesting a diet rich in antioxidants for all who exercise and train regularly.
Recently progress has been made on O2 toxicity and pathology related to numerous environmental contaminants in insects. The pro-oxidants studied included: dioxin, paraquat, and an assorted array of quinones, 8-methoxypsorlen, arsenic, and mercury. The responses to these oxidants are diverse, but they arise from the reactive oxygen species. These pro-oxidants in insects cause lipid peroxidation, protein and enzyme oxidation, and GSH depletion. Potentially, they may also cause DNA oxidation, and form DNA adducts. Oxidative challenge is alleviated by antioxidant compounds, but more importantly by the induction of antioxidant enzymes, which are crucial for the termination of O2 radical cascade and lipid peroxidation chain reaction. Insects exhibit a wasting syndrome under sub-acute stress. In acute toxicity vital physiological processes impaired are hemolymph melanization and diuresis. Thus, insects resemble vertebrates in both the response to oxidative stress and its pathological consequences. These results raise the prospect that insects may serve as non-mammalian model species for monitoring the oxidative-stress component of environmental toxicity.
Zakkar, Mustafa; Guida, Gustavo; Suleiman, M-Saadeh; Angelini, Gianni D.
The development of the cardiopulmonary bypass (CPB) revolutionized cardiac surgery and contributed immensely to improved patients outcomes. CPB is associated with the activation of different coagulation, proinflammatory, survival cascades and altered redox state. Haemolysis, ischaemia, and perfusion injury and neutrophils activation during CPB play a pivotal role in oxidative stress and the associated activation of proinflammatory and proapoptotic signalling pathways which can affect the function and recovery of multiple organs such as the myocardium, lungs, and kidneys and influence clinical outcomes. The administration of agents with antioxidant properties during surgery either intravenously or in the cardioplegia solution may reduce ROS burst and oxidative stress during CPB. Alternatively, the use of modified circuits such as minibypass can modify both proinflammatory responses and oxidative stress. PMID:25722792
Conclusion: This study demonstrates the potential benefits of pharmacological preconditioning of diabetic-mouse-derived MSCs with NAC for amelioration of apoptosis and oxidative stress in H2O2 induced injury.
Duan, Yabing; Ge, Changyan; Liu, Shengming; Wang, Jianxin; Zhou, Mingguo
Fungal histidine kinases (HKs) are involved in osmotic and oxidative stress responses, hyphal development, fungicide sensitivity and virulence. Members of HK class III are known to signal through the high-osmolarity glycerol mitogen-activated protein kinase (HOG MAPK). In this study, we characterized the Shk1 gene (SS1G_12694.3), which encodes a putative class III HK, from the plant pathogen Sclerotinia sclerotiorum. Disruption of Shk1 resulted in resistance to phenylpyrrole and dicarboximide fungicides and increased sensitivity to hyperosmotic stress and H2 O2 -induced oxidative stress. The Shk1 mutant showed a significant reduction in vegetative hyphal growth and was unable to produce sclerotia. Quantitative real-time polymerase chain reaction (qRT-PCR and glycerol determination assays showed that the expression of SsHOG1 (the last kinase of the Hog pathway) and glycerol accumulation were regulated by the Shk1 gene, but PAK (p21-activated kinase) was not. In addition, the Shk1 mutant showed no change in virulence. All the defects were restored by genetic complementation of the Shk1 deletion mutant with the wild-type Shk1 gene. These findings indicate that Shk1 is involved in vegetative differentiation, sclerotial formation, glycerol accumulation and adaption to hyperosmotic and oxidative stresses, and to fungicides, in S. sclerotiorum. Taken together, our results demonstrate, for the first time, the role of two-component HKs in Sclerotinia. © 2013 BSPP AND JOHN WILEY & SONS LTD.
Kodentsova, V M; Vrzhesinskaia, O A; Mazo, V K
The central and local stress limiting systems, including the antioxidant defense system involved in defending the organism at the cellular and systemic levels from excess activation response to stress influence, leading to damaging effects. The development of stress, regardless of its nature [cold, increased physical activity, aging, the development of many pathologies (cardiovascular, neurodegenerative diseases, diseases of the gastrointestinal tract, ischemia, the effects of burns), immobilization, hypobaric hypoxia, hyperoxia, radiation effects etc.] leads to a deterioration of the vitamin status (vitamins E, A, C). Damaging effect on the antioxidant defense system is more pronounced compared to the stress response in animals with an isolated deficiency of vitamins C, A, E, B1 or B6 and the combined vitamins deficiency in the diet. Addition missing vitamin or vitamins restores the performance of antioxidant system. Thus, the role of vitamins in adaptation to stressors is evident. However, vitamins C, E and beta-carotene in high doses, significantly higher than the physiological needs of the organism, may be not only antioxidants, but may have also prooxidant properties. Perhaps this explains the lack of positive effects of antioxidant vitamins used in extreme doses for a long time described in some publications. There is no doubt that to justify the current optimal doses of antioxidant vitamins and other dietary antioxidants specially-designed studies, including biochemical testing of initial vitamin and antioxidant status of the organism, as well as monitoring their change over time are required.
Yang, Hui; Jin, Xun; Kei Lam, Christopher Wai; Yan, Sheng-Kai
Increasing evidences have suggested that oxidative stress plays a major role in the pathogenesis of diabetes mellitus (DM). Oxidative stress also appears to be the pathogenic factor in underlying diabetic complications. Reactive oxygen species (ROS) are generated by environmental factors, such as ionizing radiation and chemical carcinogens, and also by endogenous processes, including energy metabolism in mitochondria. ROS produced either endogenously or exogenously can attack lipids, proteins and nucleic acids simultaneously in living cells. There are many potential mechanisms whereby excess glucose metabolites traveling along these pathways might promote the development of DM complication and cause pancreatic β cell damage. However, all these pathways have in common the formation of ROS, that, in excess and over time, causes chronic oxidative stress, which in turn causes defective insulin gene expression and insulin secretion as well as increased apoptosis. Various methods for determining biomarkers of cellular oxidative stress have been developed, and some have been proposed for sensitive assessment of antioxidant defense and oxidative damage in diabetes and its complications. However, their clinical utility is limited by less than optimal standardization techniques and the lack of sufficient large-sized, multi-marker prospective trials.
Bayliak, Maria M; Burdyliuk, Nadia I; Izers'ka, Lilia I; Lushchak, Volodymyr I
Concentration-dependent effects of aqueous extract from R. rosea root on long-term survival and stress resistance of budding yeast Saccharomyces cerevisiae were studied. At low concentrations, R. rosea aqueous extract extended yeast chronological lifespan, enhanced oxidative stress resistance of stationary-phase cells and resistance to number stressors in exponentially growing cultures. At high concentrations, R. rosea extract sensitized yeast cells to stresses and shortened yeast lifespan. These biphasic concentration-responses describe a common hormetic phenomenon characterized by a low-dose stimulation and a high-dose inhibition. Yeast pretreatment with low doses of R. rosea extract enhanced yeast survival and prevented protein oxidation under H2O2-induced oxidative stress. Positive effect of R. rosea extract on yeast survival under heat shock exposure was not accompanied with changes in antioxidant enzyme activities and levels of oxidized proteins. The deficiency in transcriptional regulators, Msn2/Msn4 and Yap1, abolished the positive effect of low doses of R. rosea extract on yeast viability under stress challenges. Potential involvement of Msn2/Msn4 and Yap1 regulatory proteins in realization of R. rosea beneficial effects is discussed.
Nikam, Shashikant; Nikam, Padmaja; Ahaley, S. K.; Sontakke, Ajit V.
Oxidative stress contributes to the cascade, leading to dopamine cell degeneration in Parkinson’s disease. However, oxidative stress is intimately linked to other components of the degenerative process, such as mitochondrial dysfunction, excitotoxicity, nitric oxide toxicity and inflammation. It is therefore difficult to determine whether oxidative stress leads to or is a consequence of, these events. Oxidative stress was assessed by estimating lipid peroxidation product in the form of thioba...
Full Text Available Haemophilus influenzae is a commensal of the human upper respiratory tract. H. influenzae can, however, move out of its commensal niche and cause multiple respiratory tract diseases. Such diseases include otitis media in young children, as well as exacerbations of chronic obstructive pulmonary disease, sinusitis, conjunctivitis and bronchitis. During the course of colonization and infection, H. influenzae must withstand oxidative stress generated by multiple reactive oxygen species produced endogenously, by other co-pathogens and by host cells. H. influenzae has therefore evolved multiple mechanisms that protect the cell against oxygen-generated stresses. In this review, we will describe these systems. Moreover, we will compare how H. influenzae obviates the effect of oxidative stress as a necessary phenotype for its roles as both a successful commensal and pathogen, relative to the well-described systems in Escherichia coli.
Sivonová, Monika; Zitnanová, Ingrid; Hlincíková, Lucia; Skodácek, Igor; Trebatická, Jana; Duracková, Zdenka
Mental stress in psychiatric disease and in daily life contributes to oxidative stress in the body. In this study we investigated a connection between possible psychological stress caused by university undergraduate examinations and oxidative stress experienced by our test subjects. Some parameters of oxidative stress (single strand breaks of DNA in lymphocytes, sensitivity to lipid oxidation and antioxidant status) were studied in medical students on the day of the examination (stress condition) and compared with the same parameters obtained from the same students during the term between two examination periods (non-stress condition). The results show that in the stress condition oxidative damage to DNA and sensitivity to lipid oxidation were significantly increased (pstress" conditions. A significant decrease in plasma antioxidant activity (pstress was observed. These results suggest that during university examinations students are under increased oxidative stress.
Rosa Martha Perez-Gutierrez
Full Text Available Six new flavonoids 2′,4′-dihydroxychalcone-6′-O-β-d-glucopyranoside (1, α,3,2′,4′-tetrahydroxy-4-methoxy-dihydrochalcone-3′-C-β-glucopyranosy-6′-O-β-d-glucopyranoside (2, 7-hydroxy-5,8′-dimethoxy-6′α-l-rhamnopyranosyl-8-(3-phenyl-trans-acryloyl-1-benzopyran-2-one (3, 6′7-dihydroxy-5,8-dimethoxy-8(3-phenyl-trans-acryloyl-1-benzopyran-2-one (4, 9-hydroxy-3,8-dimethoxy-4-prenylpterocarpan (5, and α,4,4′-trihydroxydihydrochalcone-2′-O-β-d-glucopyranoside (6 were isolated from bark of Eysenhardtia polystachya. Antidiabetic activity of compounds 1–5 in terms of their cellular antioxidant and free radical scavenging and also in streptozotocin- (STZ- induced diabetic mice was evaluated on liver transaminases, lipid peroxidation, total bilirubin, total protein, superoxide dismutase (SOD, catalase (CAT, glutathione peroxidase (CSH-Px, and glutathione reductase (GSH. Results indicated that 1–5 scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH, hydroxyl (OH∙, nitric oxide radicals (NO∙, superoxide anion radical (O2∙-, radical cation (ABTS∙+, and hydrogen peroxide (H2O2 radical, and protection against H2O2 induced BSA damage was also observed. Furthermore, 1–5 showed ability to decrease the oxidative stress in H9c2 cell. Diabetic mice present high levels of lipid peroxide, total protein, SGPT, SGOT, ALP, and TB. However, treatment of STZ-induced diabetes in mice with 1–5 reduced levels of these enzymes leading to protector effect of liver. In addition, with treatment with 1–5, increases in radical scavenging enzymes of CSH-Px, SOD, GSH, and CAT have also been observed in diabetic mice. The antioxidant properties of compounds 1–5 are a promising strategy for ameliorating therapeutic effects by avoiding disorders in the normal redox reactions in healthy cells which consequently could alleviate complications of diabetes.
Fogarasi Erzsébet; Croitoru Mircea Dumitru; Fülöp Ibolya; Muntean Daniela-Lucia
Oxidative stress is an imbalance between free radicals or other reactive species and the antioxidant activity of the organism. Oxidative stress can induce several illnesses such as cardiovascular disease, neurodegenerative disorders, diabetes, cancer, Alzheimer and Parkinson. The biomarkers of oxidative stress are used to test oxidative injury of biomolecules. The indicators of lipid peroxidation (malondialdehyde, 4-hydroxy- 2-nonenal, 2-propenal, isoprostanes), of protein oxidation (carbonyl...
Yang, Hongyan; Xie, Yan; Yang, Dongyu; Ren, Decheng
Reactive oxygen species (ROS) play important roles in follicular development and survival. Granulosa cell death is associated with increased ROS, but the mechanism of granulosa cell death induced by ROS is not clear. In order to define the molecular link between ROS and granulosa cell death, COV434, human granulosa tumor cells, were treated with H2O2. Compared to control cells, H2O2 induced granulosa cell death in a dose- and time-dependent manner. H2O2 induced an increase in Bax, Bak and Puma, and a decrease in anti-apoptotic molecules such as Bcl-2, Bcl-xL and Mcl-1. Both knockdown of Puma and overexpression of Bcl-xL could inhibit H2O2-induced granulosa cell death. These results suggest that suppression of Puma and overexpression of anti-apoptotic Bcl-2 family members could improve granulosa cell survival. To explore the mechanisms responsible for these findings, ROS in granulosa cells treatment with H2O2 were measured. The results showed that ROS was increased in a H2O2 dose- and time-dependent manner at the earlier time point. In addition, H2O2 induced an increase in Nrf2 and phosphorylation of JNK and p53. SP600125, an inhibitor of JNK, inhibits H2O2-induced phosphorylation of JNK and p53, and granulosa cell death. Antioxidant N-acetylcysteine (NAC) dose-dependently prevents H2O2-induced granulosa cell death. Furthermore, NAC also prevents phosphorylation of JNK and p53 induced by H2O2. Taken together, these data suggest that H2O2 regulates cell death in granulosa cells via the ROS-JNK-p53 pathway. These findings provide an improved understanding of the mechanisms underlying granulosa cell apoptosis, which could potentially be useful for future clinical applications. PMID:28445976
Wang, Cong; Gao, Yibo; Gao, Xinghua; Wang, Hua; Tian, Jingxuan; Wang, Li; Zhou, Bingpu; Ye, Ziran; Wan, Jun; Wen, Weijia
A highly efficient photochromic hydrogel was successfully fabricated via casting precursor, which is based on amorphous tungsten oxide and poly (ethylene oxide)-block-poly (propylene oxide)-block-poly (ethylene oxide). Under simulated solar illumination, the hydrogel has a rapid and controlled temperature increasing ratio as its coloration degree. Localized electrons in the amorphous tungsten oxide play a vital role in absorption over a broad range of wavelengths from 400 nm to 1100 nm, encompassing the entire visible light and infrared regions in the solar spectrum. More importantly, the material exhibits sustainable released H2O2 induced by localized electrons, which has a synergistic effect with the rapid surface temperature increase. The amount of H2O2 released by each film can be tuned by the light irradiation, and the film coloration can indicate the degree of oxidative stress. The ability of the H2O2-releasing gels in vitro study was investigated to induce apoptosis in melanoma tumor cells and NIH 3T3 fibroblasts. The in vivo experimental results indicate that these gels have a greater healing effect than the control in the early stages of tumor formation.
Moret, Inés; Cerrillo, Elena; Navarro-Puche, Ana; Iborra, Marisa; Rausell, Francisco; Tortosa, Luis; Beltrán, Belén
Crohn's disease (CD) is characterized by transmural inflammation that is most frequently located in the region of the terminal ileum. Although the physiopathological mechanisms of the disease are not yet well defined, the unregulated immune response is associated with high production of reactive oxygen species (ROS). These elements are associated with complex systems known as antioxidant defenses, whose function is ROS regulation, thereby preventing the harmful effects of these elements. However, the presence of an imbalance between ROS production and ROS elimination by antioxidants has been widely described and leads to oxidative stress. In this article, we describe the most significant findings on oxidative stress in the intestinal mucosa and peripheral blood. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.
M. V. Belova
Full Text Available Objective: to comparatively assess the intensity of oxidative stress (OS in acute poisonings by various toxic chemicals. Subjects and methods. Two hundred and eighty-seven patients with acute poisoning by psychopharmacological agents, ethanol, and cauterants were examined. Results. A correlation was found between the manifestations of OS and the severity of poisoning. The investigators revealed the impacts of exposure to toxic chemicals and complications of the toxicogenic phase of acute poisoning by the above toxicants on the intensity of OS. Conclusion. The intensity of OS in the poisonings under study increases in proportion to the severity of intoxication, toxicant exposure in the body. The presence of hemolysis, upper airway burn, and chronic alcoholism deteriorate OS. Key words: oxidative stress, acute poisonings, chemical burn, chronic alcoholism.
Liu, Dongping; Xu, Yang
Mammalian aging is associated with elevated levels of oxidative damage of DNA, proteins, and lipids as a result of unbalanced prooxidant and antioxidant activities. Accumulating evidence indicates that oxidative stress is a major physiological inducer of aging. p53, the guardian of the genome that is important for cellular responses to oxidative stresses, might be a key coordinator of oxidative stress and aging. In response to low levels of oxidative stresses, p53 exhibits antioxidant activities to eliminate oxidative stress and ensure cell survival; in response to high levels of oxidative stresses, p53 exhibits pro-oxidative activities that further increase the levels of stresses, leading to cell death. p53 accomplishes these context-dependent roles by regulating the expression of a panel of genes involved in cellular responses to oxidative stresses and by modulating other pathways important for oxidative stress responses. The mechanism that switches p53 function from antioxidant to prooxidant remains unclear, but could account for the findings that increased p53 activities have been linked to both accelerated aging and increased life span in mice. Therefore, a balance of p53 antioxidant and prooxidant activities in response to oxidative stresses could be important for longevity by suppressing the accumulation of oxidative stresses and DNA damage.
Damisela Ramírez Ramírez
Full Text Available Background: aging is one of the major problems that the world is facing today due to its impact on all areas of society. Objective: to determine the concentrations of advanced oxidation protein products and malondialdehyde as indicators of oxidative damage and to determine the antioxidant defense capacity of the enzymes superoxide dismutase, catalase and the reduced glutathione concentration in aged rats. Methods: a total of 20 male Wistar rats with a body weight of approximately 200 to 250 grams were selected to form two groups with 10 young adult rats and 10 old rats. 2 ml of blood was drawn from the paranasal sinus. The sample was collected in 5 ml vials and after being homogenized, it was sent to the Biomedical Research Center, where it was used to assess the following oxidative stress variables: degree of oxidative damage and antioxidant defense level. An analysis of variance was performed to study the behavior of the different groups. Differences were considered significant when P value was less than 0.05. Results: no significant changes were found in the concentrations of malondialdehyde and glutathione, as well as in the superoxide dismutase and catalase activity in aged rats compared to young. Concentration of advanced oxidation protein products increased significantly in aged rats. Conclusions: aged rats showed an increase in oxidative damage to proteins. Antioxidant defense capacity of the enzymes superoxide dismutase and catalase and reduced glutathione concentration showed no changes.
Full Text Available It is well known that G6PD-deficient individuals are highly susceptible to oxidative stress. However, the differences in the degree of metabolic alterations among patients during an oxidative crisis have not been extensively studied. In this study, we applied mathematical modeling to assess the metabolic changes in erythrocytes of various G6PD-deficient patients during hydrogen peroxide- (H2O2- induced perturbation and predict the kinetic properties that elicit redox imbalance after exposure to an oxidative agent. Simulation results showed a discrepancy in the ability to restore regular metabolite levels and redox homeostasis among patients. Two trends were observed in the response of redox status (GSH/GSSG to oxidative stress, a mild decrease associated with slow recovery and a drastic decline associated with rapid recovery. The former was concluded to apply to patients with severe clinical symptoms. Low max and high mG6P of G6PD were shown to be kinetic properties that enhance consequent redox imbalance.
Young, In-Chi; Chuang, Sung-Ting; Hsu, Chia-Hsien; Sun, Yu-Jun; Lin, Feng-Huei
During the progression of osteoarthritis (OA), dysregulation of extracellular matrix anabolism, abnormal generation of reactive oxygen species (ROS) and inflammatory cytokines have been shown to accelerate the degradation process of cartilage. The potency of c-phycocyanin (C-PC) to protect cellular components against oxidative stress, along with its anti-inflammation and anti-apoptosis effects, are well documented; however, effects of C-PC on OA are still unclear. In this study, we aimed to investigate the effects of C-PC on OA using H2O2 or compression-stimulated OA-like porcine chondrocyte models. The results showed that C-PC had the ability to inhibit ROS production, reverse caspase-3 activity, and reduce apoptosis cell population. C-PC also reversed aggrecan and type II collagen gene expressions after stimulation with 1mM H2O2 or 60psi of compression. Inhibition of IL-6 and MMP-13 genes was observed in compression-stimulated chondrocytes but not in H2O2-treated cells. In dimethylmethylene blue assay and alcian blue staining, C-PC maintained the sulfated-glycosaminoglycan (sGAG) content after stimulation with compression. We concluded that C-PC can prevent early signs of OA caused by compressive stress and attenuate H2O2-induced oxidative stress. Therefore, we suggest that C-PC can be used as a potential drug candidate for chronic OA treatment. Copyright © 2016 Elsevier B.V. All rights reserved.
Kohr, Mark J; Evangelista, Alicia M; Ferlito, Marcella; Steenbergen, Charles; Murphy, Elizabeth
Oxidative stress and membrane damage following myocardial ischemia/reperfusion injury are important contributors to cardiomyocyte death and the loss of myocardial function. Our previous study identified cysteine 144 (C144) of tripartite motif-containing protein 72 (TRIM72) as a potential site for S-nitrosylation (SNO). TRIM72 is a cardioprotective membrane repair protein that can be both activated and targeted for degradation by different oxidative modifications. Consistent with the potential regulation of TRIM72 by various oxidative modifications, we found that SNO levels increased at C144 of TRIM72 with ischemic preconditioning. Therefore, to investigate the role of C144 in the regulation of TRIM72 function, we mutated C144 of TRIM72 to a serine residue (TRIM72(C144S)), and expressed either TRIM72(WT) or TRIM72(C144S) in HEK-293 cells, which lack endogenous TRIM72, in order to examine the effect of this mutation on the functional stability of TRIM72 and on cell survival. We hypothesized that SNO of TRIM72 stabilizes the protein, thus allowing for membrane repair and enhanced cell survival. Upon treatment with hydrogen peroxide (H2O2), we found that TRIM72(WT) levels were decreased, but not TRIM72(C144S) and this correlated with increased H2O2-induced cell death in TRIM72(WT) cells. Additionally, we found that treatment with the cardioprotective S-nitrosylating agent S-nitrosoglutathione (GSNO), was able to preserve TRIM72(WT) protein levels and enhance TRIM72(WT)-mediated cell survival, but had no effect on TRIM72(C144S) levels. Consistent with our hypothesis, GSNO was also found to increase SNO levels and inhibit H2O2-induced irreversible oxidation for TRIM72(WT) without affecting TRIM72(C144S). In further support of our hypothesis, GSNO blocked the ischemia/reperfusion-induced decrease in TRIM72 levels and reduced infarct size in a Langendorff-perfused heart model. The results of these studies have important implications for cardioprotection and suggest that
Full Text Available The chemopreventive potential of water extracts of the Brassica vegetables cabbage and kale was evaluated by administering their aqueous extracts in drinking water ad libitum to Wistar rats submitted to Ito’s hepatocarcinogenesis model (CB group and K group, respectively - 14 rats per group. Animals submitted to this same model and treated with water were used as controls (W group - 15 rats. Treatment with the vegetable extracts did not inhibit (P > 0.05 placental glutathione S-transferase-positive preneoplastic lesions (PNL. The number of apoptotic bodies did not differ (P > 0.05 among the experimental groups. Ex vivo hydrogen peroxide treatment of rat livers resulted in lower (P < 0.05 DNA strand breakage in cabbage- (107.6 ± 7.8 µm and kale- (110.8 ± 10.0 µm treated animals compared with control (120.9 ± 12.7 µm, as evaluated by the single cell gel (comet assay. Treatment with cabbage (2 ± 0.3 µg/g or kale (4 ± 0.2 µg/g resulted in increased (P < 0.05 hepatic lutein concentration compared with control (0.5 ± 0.07 µg/g. Despite the absence of inhibitory effects of cabbage and kale aqueous extracts on PNL, these Brassica vegetables presented protection against DNA damage, an effect possibly related to increased hepatic lutein concentrations. However, it must be pointed out that the cause-effect relationship between lutein levels and protection is hypothetical and remains to be demonstrated.
Wei, Zhen-Hua; Bai, Linquan; Deng, Zixin; Zhong, Jian-Jiang
A novel fermentation strategy to enhance antibiotics production was demonstrated by inducing reactive oxygen species (ROS), and validamycin A (VAL-A) production by Streptomyces hygroscopicus 5008 in agro-industrial residues containing medium was taken as an example. By optimizing H2O2 amount and addition time, the intracellular ROS level was increased, and VAL-A production titer was enhanced by 40% on day 4 when 25 μM H2O2 was added at 8th h of fermentation. Addition of diphenyleneiodonium chloride (ROS inhibitor) reduced the H2O2 induction effect. The transcription level of eight VAL-A structure genes was enhanced by ROS, and activities of glucose-6-phosphate dehydrogenase and ValG enzyme were increased while glyceraldehyde 3-phosphate dehydrogenase activity was inhibited. This work demonstrated that ROS induction was a useful strategy for VAL-A fermentation, and the information on gene transcription and enzyme activities may be helpful to further understanding the mechanism of ROS effect on the antibiotic biosynthesis. Copyright Â© 2010. Published by Elsevier Ltd.
Wong, P S; Garle, M J; Alexander, S P H; Randall, M D; Roberts, R E
Hydrogen peroxide (H2O2) has been proposed to act as a factor for endothelium-derived hyperpolarization (EDH) and EDH may act as a 'back up' system to compensate the loss of the NO pathway. Here, the mechanism of action of H2O2 in porcine isolated coronary arteries (PCAs) was investigated. Distal PCAs were mounted in a wire myograph and pre-contracted with U46619 (1nM-50μM), a thromboxane A2-mimetic or KCl (60mM). Concentration-response curves to H2O2(1μM-1mM), bradykinin (0.01nM-1μM), sodium nitroprusside (SNP) (10nM-10μM), verapamil (1nM-10μM), KCl (0-20mM) or Ca(2+)-reintroduction (1μM-10mM) were constructed in the presence of various inhibitors. Activity of the Na(+)/K(+)-pump was measured through rubidium-uptake using atomic absorption spectrophotometry. H2O2 caused concentration-dependent vasorelaxations with a maximum relaxation (Rmax) of 100±16% (mean±SEM), pEC50=4.18±0.20 (n=4) which were significantly inhibited by PEG-catalase at 0.1-1.0mM H2O2 (Ppump activity. We have shown that the vascular actions of H2O2 are sensitive to ouabain and high concentrations of H2O2 are able to modulate the Na(+)/K(+)-pump. This may contribute towards its vascular actions. Copyright © 2014 Elsevier Ltd. All rights reserved.
Prie, B E; Iosif, L; Tivig, I; Stoian, I; Giurcaneanu, C
Rationale: Androgenetic alopecia is not considered a life threatening disease but can have serious impacts on the patient's psychosocial life. Genetic, hormonal, and environmental factors are considered responsible for the presence of androgenetic alopecia. Recent literature reports have proved the presence of inflammation and also of oxidative stress at the level of dermal papilla cells of patients with androgenetic alopecia Objective: We have considered of interest to measure the oxidative stress parameters in the blood of patients with androgenetic alopecia Methods and results: 27 patients with androgenetic alopecia and 25 age-matched controls were enrolled in the study. Trolox Equivalent Antioxidant Capacity (TEAC), malondialdehyde (MDA) and total thiols levels were measured on plasma samples. Superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) activities, and also non protein thiols levels together with TEAC activity were determined on erythrocytes samples No statistically significant changes were observed for TEAC erythrocytes, non-protein thiols, GPx and CAT activities. Significantly decreased (palopecia. For plasma samples decreased TEAC activity (palopecia are indicators of oxidative stress presence in these patients. Significantly decreased SOD activity but no change in catalase, glutathione peroxidase, non protein thiols level and total antioxidant activity in erythrocytes are elements which suggest the presence of a compensatory mechanism for SOD dysfunction in red blood cells of patients with androgenetic alopecia. AAG = androgenetic alopecia, MDA = malondialdehyde, SOD = superoxide dismutase, CAT = catalase, GPx = glutathione peroxidase, GSH = glutathione, GST = glutathione transferase, SH = thiols, TEAC = trolox equivalent antioxidant capacity, ABTS = 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), CDNB = 1-chloro-2,4-dinitrobenzene.
Shyamal K Goswami
Full Text Available Oxidative stress caused by various oxygen containing free radicals and reactive species (collectively called "Reactive Oxygen Species" or ROS has long been attributed to cardiovascular diseases. In human body, major oxidizing species are super oxide, hydrogen peroxide, hydroxyl radical, peroxy nitrite etc. ROS are produced from distinct cellular sources, enzymatic and non-enzymatic; have specific physicochemical properties and often have specific cellular targets. Although early studies in nineteen sixties and seventies highlighted the deleterious effects of these species, later it was established that they also act as physiological modulators of cellular functions and diseases occur only when ROS production is deregulated. One of the major sources of cellular ROS is Nicotinamide adenine dinucleotide phosphate oxidases (Noxes that are expressed in almost all cell types. Superoxide and hydrogen peroxide generated from them under various conditions act as signal transducers. Due to their immense importance in cellular physiology, various Nox inhibitors are now being developed as therapeutics. Another free radical of importance in cardiovascular system is nitric oxide (a reactive nitrogen species generated from nitric oxide synthase(s. It plays a critical role in cardiac function and its dysregulated generation along with superoxide leads to the formation of peroxynitrite a highly deleterious agent. Despite overwhelming evidences of association between increased level of ROS and cardiovascular diseases, antioxidant therapies using vitamins and omega 3 fatty acids have largely been unsuccessful till date. Also, there are major discrepancies between studies with laboratory animals and human trials. It thus appears that the biology of ROS is far complex than anticipated before. A comprehensive understanding of the redox biology of diseases is thus needed for developing targeted therapeutics.
José A. Morales-González
Full Text Available Obesity is a chronic disease of multifactorial origin and can be defined as an increase in the accumulation of body fat. Adipose tissue is not only a triglyceride storage organ, but studies have shown the role of white adipose tissue as a producer of certain bioactive substances called adipokines. Among adipokines, we find some inflammatory functions, such as Interleukin-6 (IL-6; other adipokines entail the functions of regulating food intake, therefore exerting a direct effect on weight control. This is the case of leptin, which acts on the limbic system by stimulating dopamine uptake, creating a feeling of fullness. However, these adipokines induce the production of reactive oxygen species (ROS, generating a process known as oxidative stress (OS. Because adipose tissue is the organ that secretes adipokines and these in turn generate ROS, adipose tissue is considered an independent factor for the generation of systemic OS. There are several mechanisms by which obesity produces OS. The first of these is the mitochondrial and peroxisomal oxidation of fatty acids, which can produce ROS in oxidation reactions, while another mechanism is over-consumption of oxygen, which generates free radicals in the mitochondrial respiratory chain that is found coupled with oxidative phosphorylation in mitochondria. Lipid-rich diets are also capable of generating ROS because they can alter oxygen metabolism. Upon the increase of adipose tissue, the activity of antioxidant enzymes such as superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GPx, was found to be significantly diminished. Finally, high ROS production and the decrease in antioxidant capacity leads to various abnormalities, among which we find endothelial dysfunction, which is characterized by a reduction in the bioavailability of vasodilators, particularly nitric oxide (NO, and an increase in endothelium-derived contractile factors, favoring atherosclerotic disease.
Kin Weng Kong
Full Text Available Barringtonia racemosa is a tropical plant with medicinal values. In this study, the ability of the water extracts of the leaf (BLE and stem (BSE from the shoots to protect HepG2 cells against oxidative damage was studied. Five major polyphenolic compounds consisting of gallic acid, ellagic acid, protocatechuic acid, quercetin and kaempferol were identified using HPLC-DAD and ESI-MS. Cell viability assay revealed that BLE and BSE were non-cytotoxic (cell viabilities >80% at concentration less than 250 µg/ml and 500 µg/ml, respectively. BLE and BSE improved cellular antioxidant status measured by FRAP assay and protected HepG2 cells against H2O2-induced cytotoxicity. The extracts also inhibited lipid peroxidation in HepG2 cells as well as the production of reactive oxygen species. BLE and BSE could also suppress the activities of superoxide dismutase and catalase during oxidative stress. The shoots of B. racemosa can be an alternative bioactive ingredient in the prevention of oxidative damage.
Zhao, Danyue; Shah, Nagendra P
In view of the potential of lactic acid bacteria (LAB) to enhance the antioxidant activity of food products, this work explored the effectiveness of LAB fermented black tea samples in alleviating H2O2-induced oxidative stress in human colonocytes. The antioxidant capacity of tea samples was evaluated in terms of cyto-protectiveness, mitochondria membrane potential (Δψm)-stabilizing activity, ROS-inhibitory effect, and antioxidant enzyme-modulating activity. The effect on oxidative DNA damage and repair was studied in CCD 841 by comet assay. Results showed that the protective effect of tea pretreatment was more pronounced in normal cells (CCD 841) than in carcinomas (Caco-2), and fermented samples were invariably more effective. Higher cell viability and Δψm were maintained and ROS production was markedly inhibited with tea pretreatment. The fermented tea samples also remarkably stimulated DNA repair, resulting in fewer strand breaks and oxidative lesions. Our study implied that LAB fermentation may be an efficient way to enhance the antioxidative effectiveness of black tea flavonoid-enriched foods.
An investigation of the effects of Cinnamomum cassia bark extracts on oxidative DNA damage and possible cytotoxic and apoptotic activities in transformed/untransformed cell lines from Type 1 diabetic patients, in vitro.
Ferzan Lermioglu Erciyas
Full Text Available It was shown that patients with Type 1 diabetes mellitus (T1DM had increased level of oxidative DNA damage and decreased efficacy of DNA repair. These changes were implicated in the increased cancer risk in patients with diabetes mellitus. Cinnamon bark extracts have diverse biological activities including antidiabetic and anti-tumor properties. Cinnamomum cassia (C. cassia is a common used cinnamon species present in commercial cinnamon preparations. We aimed to investigate the effects of cinnamon extracts prepared from C. cassia bark on endogenous and hydrogen peroxide (H2O2-induced oxidative DNA damage, as well as cytotoxic and apoptotic activities in this study. Type 1 diabetic (T1DM lymphocytes (GM02765, GM01838 and fibroblasts (GM01837 were obtained from NIGMS Human Genetic Cell Repository of Coriell Institute, New Jersey, USA. Cytotoxicity analysis were performed by using a tetrazolium salt, 4-[3-(4-iodophenyl 2-(4-nitrophenyl 2H-5-tetrazolio] 1,3-benzene disulfonate (WST-1. The effects of extracts on endogenous and H2O2-induced oxidative DNA damage were studied using the single cell gel electrophoresis (SCGE; Comet Assay, a technique allowing DNA damage in a single cell. Apoptotic activities of extracts were investigated by TUNEL and Annexin V/PI assays. using flow cytometry. IC50 and IC20 values of the extracts varied and the effects on endogenous and H2O2-induced DNA damage were different regarding cell lines and extracts. Although their protective effects at some doses against to H2O2-induced oxidative damage, our results suggested DNA damaging and apoptotic potential of cinnamon bark extracts on Type 1 diabetic cell lines, in vitro.
Full Text Available Sperm is particularly susceptible to reactive oxygen species (ROS during critical phases of spermiogenesis. However, the level of seminal ROS is restricted by seminal antioxidants which have beneficial effects on sperm parameters and developmental potentials. Mitochondria and sperm plasma membrane are two major sites of ROS generation in sperm cells. Besides, leukocytes including polymer phonuclear (PMN leukocytes and macrophages produce broad category of molecules including oxygen free radicals, non-radical species and reactive nitrogen species. Physiological role of ROS increase the intracellular cAMP which then activate protein kinase in male reproductive system. This indicates that spermatozoa need small amounts of ROS to acquire the ability of nuclear maturation regulation and condensation to fertilize the oocyte. There is a long list of intrinsic and extrinsic factors which can induce oxidative stress to interact with lipids, proteins and DNA molecules. As a result, we have lipid peroxidation, DNA fragmentation, axonemal damage, denaturation of the enzymes, over generation of superoxide in the mitochondria, lower antioxidant activity and finally abnormal spermatogenesis. If oxidative stress is considered as one of the main cause of DNA damage in the germ cells, then there should be good reason for antioxidant therapy in these conditions
Gómez-Zubeldia, María Angeles; Bazo, Ascensión Pérez; Gabarre, Juan José Arbués; Nogales, Agustín García; Palomino, José Carlos Millán
Reactive oxygen species seem to be involved in the onset and promotion of carcinogenesis. In 80% of cases of endometrial adenocarcinoma type I, a clear association exists with endometrial hyperplasia, which is considered a key factor in the endometrial oncological spectrum. The presence or absence of atypical cells determines oncological potential. This study explored the behavior of oxidative stress (catalase and malondialdehyde) in endometrial hyperplasia (with or without atypical cells) by comparing it with the oxidative stress existing in both the proliferative and secretory phases. Endometrial specimens from 55 women were used, 32 of which were histologically diagnosed as physiological (17 proliferative and 15 secretory endometria) and 23 as endometrial hyperplasia (18 nonatypical and 5 atypical endometrial hyperplasia). Significant differences were found in the malondialdehyde variable between the proliferative endometrium and the endometrium with atypical hyperplasia (P = 0.0208) and between both types of endometrial hyperplasia (P = 0.0441). The other comparisons were not statistically significant. No changes in catalase activity were observed. Our findings seem to suggest that the presence of atypical cells in endometrial hyperplasia induces a reduction in lipid peroxidation, which could permit survival and growth of these cells. This possible decrease in lipid peroxidation does not seem to be mediated by an increase in endometrial catalase activity.
Renu A. Kowluru
Full Text Available Oxygen metabolism is essential for sustaining aerobic life, and normal cellular homeostasis works on a fine balance between the formation and elimination of reactive oxygen species (ROS. Oxidative stress, a cytopathic consequence of excessive production of ROS and the suppression of ROS removal by antioxidant defense system, is implicated in the development of many diseases, including Alzheimer's disease, and diabetes and its complications. Retinopathy, a debilitating microvascular complication of diabetes, is the leading cause of acquired blindness in developed countries. Many diabetes-induced metabolic abnormalities are implicated in its development, and appear to be influenced by elevated oxidative stress; however the exact mechanism of its development remains elusive. Increased superoxide concentration is considered as a causal link between elevated glucose and the other metabolic abnormalities important in the pathogenesis of diabetic complications. Animal studies have shown that antioxidants have beneficial effects on the development of retinopathy, but the results from very limited clinical trials are somewhat ambiguous. Although antioxidants are being used for other chronic diseases, controlled clinical trials are warranted to investigate potential beneficial effects of antioxidants in the development of retinopathy in diabetic patients.
V. V. Evdokimov
Full Text Available The study objective was to evaluate the level of oxidative stress and antioxidant defense of the ejaculate in different types of sperm pathologies caused by reproductive system disorders including varicocele, idiopathic asthenozoospermia, non-obstructive asthenozoospermia. Patients groups included 14, 11, and 16 men aged 20–45.Methods of ejaculate examination included study of morphological parameters in accordance with the 5th edition of the World Health Organization Guidelines. Biochemical parameters of the spermoplasm were measured according to the standard procedures described in previous articles.The study included men with abnormal sperm motility and morphology in the ejaculate, i. e. men with sperm pathologies in the form of asthenozoospermia. Morphological and biochemical changes were detected in the patient groups with varicocele and with asthenoand azoospermia compared to the normospermia group.In the separate varicocele group, patients were examined before and after varicocelectomy. Morphological parameters of the ejaculate didn’t show significant improvement, but biochemical parameters of the spermoplasm changed significantly: total antioxidant activity increased, the level of superoxide dismutase decreased which demonstrates decreased effect of oxidative stress after varicocelectomy.
Thompson, Loren P.; Yazan Al-Hasan
Intrauterine stress induces increased risk of adult disease through fetal programming mechanisms. Oxidative stress can be generated by several conditions, such as, prenatal hypoxia, maternal under- and overnutrition, and excessive glucocorticoid exposure. The role of oxidant molecules as signaling factors in fetal programming via epigenetic mechanisms is discussed. By linking oxidative stress with dysregulation of specific target genes, we may be able to develop therapeutic strategies that pr...
Maria Helena Vaisbich
Full Text Available Background/Aims: Nephropathic cystinosis (NC is a severe systemic disease and cysteamine improves its prognosis. Lysosomal cystine accumulation is the hallmark of cystinosis and is regarded as the primary defect due to mutations in the CTNS gene. However, there is great evidence that cystine accumulation itself is not responsible for all abnormalities observed in NC. Studies have demonstrated altered ATP metabolism, increased apoptosis, and cell oxidation. An increased number of autophagosomes and autophagic vacuoles have been observed in cystinotic fibroblasts and renal epithelial cells, suggesting that altered autophagy plays a role in NC, leading to increased production of reactive oxygen species. Therefore, cystinosis patients can be more susceptible to oxidative stress (OS and it can contribute to the progression of the renal disease. Our goal was to evaluate a marker of OS (serum TBARS in NC children, and to compare the results with those observed in healthy controls and correlated with renal function parameters. Methods: The study included patients aged under 18 years, with good adherence to the treatment and out of renal replacement therapy. The following parameters were evaluated: serum creatinine, BUN, creatinine clearance estimated by stature and serum TBARS levels. Results: We selected 20 patients aged 8.0 ±3.6 years and observed serum TBARS levels of 4.03 ±1.02 nmol/ml. Serum TBARS levels in the 43 healthy controls, aged 7.4 ±1.1 years, were 1.60 ±0.04 nmol/ml. There was a significant difference between the plasma TBARS levels among the 2 groups (p Conclusion: An increased level of serum TBARS in patients with NC was observed and this abnormality was not correlated with the renal function status degree. This is the first report that shows increased oxidative stress in serum of NC patients.
Ruder, Elizabeth H.; Hartman, Terryl J.; Goldman, Marlene B.
Purpose of review To review the role of oxidative stress in the context of female fertility. Recent findings Oxidative stress is associated with decreased female fertility in animal and in-vitro models, but no studies to date have directly assessed the relationship in women. Exposures associated with oxidative stress and with evidence to influence the timing and maintenance of a viable pregnancy include pregnancy complications (e.g. preeclampsia), extremes of body weight, alcohol, tobacco, and caffeine intake. Intake of antioxidant nutrients, including use of multivitamins, impacts the generation of reactive oxygen species and may play a beneficial role in female fertility. Summary Infertility is a significant public health problem and diagnosis and treatment are stressful, invasive, and costly. The role of oxidative stress in female fertility is an understudied and compelling area for investigation. Identifying modifiable factors to decrease oxidative stress in the gynecologic environment may be an inexpensive and noninvasive therapy for increasing fertility. PMID:19469044
Wood, J M; Decker, H; Hartmann, H; Chavan, B; Rokos, H; Spencer, J D; Hasse, S; Thornton, M J; Shalbaf, M; Paus, R; Schallreuter, K U
Senile graying of human hair has been the subject of intense research since ancient times. Reactive oxygen species have been implicated in hair follicle melanocyte apoptosis and DNA damage. Here we show for the first time by FT-Raman spectroscopy in vivo that human gray/white scalp hair shafts accumulate hydrogen peroxide (H(2)O(2)) in millimolar concentrations. Moreover, we demonstrate almost absent catalase and methionine sulfoxide reductase A and B protein expression via immunofluorescence and Western blot in association with a functional loss of methionine sulfoxide (Met-S=O) repair in the entire gray hair follicle. Accordingly, Met-S=O formation of Met residues, including Met 374 in the active site of tyrosinase, the key enzyme in melanogenesis, limits enzyme functionality, as evidenced by FT-Raman spectroscopy, computer simulation, and enzyme kinetics, which leads to gradual loss of hair color. Notably, under in vitro conditions, Met oxidation can be prevented by L-methionine. In summary, our data feed the long-voiced, but insufficiently proven, concept of H(2)O(2)-induced oxidative damage in the entire human hair follicle, inclusive of the hair shaft, as a key element in senile hair graying, which does not exclusively affect follicle melanocytes. This new insight could open new strategies for intervention and reversal of the hair graying process.
D. Rook (Denise)
textabstractDue to immature antioxidant defenses, preterm infants are at susceptible to oxidative stress, which is associated with bronchopulmonary dysplasia, retinopathy of prematurity and periventricular leukomalacia. The general aim of this thesis was to study oxidative stress in preterm infants
Flores, Lisa C; Ortiz, Melanie; Dube, Sara; Hubbard, Gene B; Lee, Shuko; Salmon, Adam; Zhang, Yiqiang; Ikeno, Yuji
The Free Radical or Oxidative Stress Theory of Aging is one of the most popular theories in aging research and has been extensively studied over the past several decades. However, recent evidence using transgenic/knockout mice that overexpress or down-regulate antioxidant enzymes challenge the veracity of this theory since the animals show no increase or decrease in lifespan. These results seriously call into question the role of oxidative damage/stress in the aging process in mammals. Therefore, the theory requires significant modifications if we are to understand the relationship between aging and the regulation of oxidative stress. Our laboratory has been examining the impacts of thioredoxins (Trxs), in the cytosol and mitochondria, on aging and age-related diseases. Our data from mice that are either up-regulating or down-regulating Trx in different cellular compartments, that is, the cytosol or mitochondria, could shed some light on the role of oxidative stress and its pathophysiological effects. The results generated from our lab and others may indicate that: 1) changes in oxidative stress and the redox state in the cytosol, mitochondria or nucleus might play different roles in the aging process; 2) the role of oxidative stress and redox state could have different pathophysiological consequences in different tissues/cells, for example, mitotic vs. post-mitotic; 3) oxidative stress could have different pathophysiological impacts in young and old animals; and 4) the pathophysiological roles of oxidative stress and redox state could be controlled through changes in redox-sensitive signaling, which could have more diverse effects on pathophysiology than the accumulation of oxidative damage to various molecules. To critically test the role of oxidative stress on aging and age-related diseases, further study is required using animal models that regulate oxidative stress levels differently in each cellular compartment, each tissue/organ, and/or at different stages
Markan, Suchita; Kohli, Harbir Singh; Sud, Kamal
To evaluate the status of oxidative stress in patients with different primary glomerular diseases (PGD) which have differential predisposition to renal failure.......To evaluate the status of oxidative stress in patients with different primary glomerular diseases (PGD) which have differential predisposition to renal failure....
as ulcers, neuropathy, and nephropathy which are known to affect oxidative stress parameters were excluded from the study. Any subject receiving antioxidant ... Oxidative stress in diabetic patients with retinopathy. After obtaining written consent, with 8 h of fasting,. 10 ml of venous blood was collected from the median.
Introduction: Oxidative stress contributes to the pathogenesis of many disease states including preeclampsia. However the degree of change and the precise timing of the tilt from balanced to oxidative stress is not well document in preeclamptic toxaemia of pregnancy in Nigerian women. This underlined the basis of this ...
Luis Eduardo Soares Netto
Full Text Available Oxidative stress response in plants is still poorly understood in comparison with the correspondent phenomenon in bacteria, yeast and mammals. For instance, nitric oxide is assumed to play various roles in plants although no nitric oxide synthase gene has yet been isolated. This research reports the results of a search of the sugarcane expressed sequence tag (SUCEST database for homologous sequences involved in the oxidative stress response. I have not found any gene similar to nitric oxide synthase in the SUCEST database although an alternative pathway for nitric oxide synthesis was proposed. I have also found several genes involved in antioxidant defense, e.g. metal chelators, low molecular weight compounds, antioxidant enzymes and repair systems. Ascorbate (vitamin C is a key antioxidant in plants because it reaches high concentrations in cells and is a substrate for ascorbate peroxidase, an enzyme that I found in different isoforms in the SUCEST database. I also found many enzymes involved in the biosynthesis of low molecular weight antioxidants, which may be potential targets for genetic manipulation. The engineering of plants for increased vitamin C and E production may lead to improvements in the nutritional value and stress tolerance of sugarcane. The components of the antioxidant defense system interact and their synthesis is probably closely regulated. Transcription factors involved in regulation of the oxidative stress response in bacteria, yeast and mammals differ considerably among themselves and when I used them to search the SUCEST database only genes with weak similarities were found, suggesting that these transcription regulators are not very conserved. The involvement of reactive oxygen species and antioxidants in plant defense against pathogens is also discussed.A resposta ao estresse oxidativo não é bem conhecida em plantas como em bactérias, leveduras e humanos. Por exemplo, assume-se que óxido nítrico tem várias fun
Miura, Yuri; Endo, Tamao
Oxidative stress is recognized as an important environmental factor in aging; however, because reactive oxygen species (ROS) and related free radicals are normally produced both intra- and extracellularly, air-living organisms cannot avoid the risk of oxidative stress. Consequently, these organisms have evolved various anti-oxidant systems to prevent ROS, scavenge free radicals, repair damaged components and adaptive responses. This review will focus on the repair and adaptive response to oxidative stress, and summarize the changes of these systems as a result aging and their relationship to premature aging.
Babu Rao; Santhoshi; Sridhar V; Souris; Margaret
Non - enzymatic free radical mediated oxidation of biological molecules, membranes and tissues is associated with a variety of pathological events such as cancer, aging and diabetes mellitus .  Increased oxidative stress is seen in both types of diabetes me llitus namely type 1 and type 2, irrespective of duration, complications and treatment. In diabetes mellitus, oxidative stress seems primarily due to both an increased plasma free radical concentra...
Full Text Available Non - enzymatic free radical mediated oxidation of biological molecules, membranes and tissues is associated with a variety of pathological events such as cancer, aging and diabetes mellitus .  Increased oxidative stress is seen in both types of diabetes me llitus namely type 1 and type 2, irrespective of duration, complications and treatment. In diabetes mellitus, oxidative stress seems primarily due to both an increased plasma free radical concentration and a sharp decline in antioxidant defences .  Among the causes of enhanced free radical production, hyperglycemia and hyper insulinemia seem to play a major role , [2,3] Hyperglycemia is the more easily modifiable factor among the two and good glycemic control can reduce the oxidative stress. Controversy pers ists regarding the other possible mechanisms of increased oxidative stress in diabetes and whether oxidative stress normalizes with adequate metabolic control alone. The role of oxidative stress and diabetic complications has been extensively investigated. Oxidative stress has been suggested to be involved in the genesis of both macro and micro angiopathy [4,5] Prospective trials are now underway addressing the controversial issues of possible role of pharmacological antioxidants in preventing or at least de laying the onset of diabetic complications.
Full Text Available Oxidative stress is an imbalance between free radicals or other reactive species and the antioxidant activity of the organism. Oxidative stress can induce several illnesses such as cardiovascular disease, neurodegenerative disorders, diabetes, cancer, Alzheimer and Parkinson. The biomarkers of oxidative stress are used to test oxidative injury of biomolecules. The indicators of lipid peroxidation (malondialdehyde, 4-hydroxy- 2-nonenal, 2-propenal, isoprostanes, of protein oxidation (carbonylated proteins, tyrosine derivatives, of oxidative damage of DNA, and other biomarkers (glutathione level, metallothioneins, myeloperoxidase activity are the most used oxidative stress markers. Diseases caused by oxidative stress can be prevented with antioxidants. In human body are several enzymes with antioxidant capacity (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and spin traps. Antioxidants are synthetized in the organism (glutathione or arrive in the body by nutrition (ascorbic acid, vitamin E, carotenoids, flavonoids, resveratrol, xanthones. Different therapeutic strategies to reduce oxidative stress with the use of synthetic molecules such as nitrone-based antioxidants (phenyl-α-tert-butyl-nitrone (PBN, 2,4-disulphophenyl- N-tert-butylnitrone (NXY-059, stilbazulenyl nitrone (STAZN, which scavenge a wide variety of free radical species, increase endogenous antioxidant levels and inhibits free radical generation are also tested in animal models.
Frijhoff, Jeroen; Winyard, Paul G; Zarkovic, Neven
SIGNIFICANCE: Oxidative stress is considered to be an important component of various diseases. A vast number of methods have been developed and used in virtually all diseases to measure the extent and nature of oxidative stress, ranging from oxidation of DNA to proteins, lipids, and free amino...... acids. RECENT ADVANCES: An increased understanding of the biology behind diseases and redox biology has led to more specific and sensitive tools to measure oxidative stress markers, which are very diverse and sometimes very low in abundance. CRITICAL ISSUES: The literature is very heterogeneous....... It is often difficult to draw general conclusions on the significance of oxidative stress biomarkers, as only in a limited proportion of diseases have a range of different biomarkers been used, and different biomarkers have been used to study different diseases. In addition, biomarkers are often measured...
Full Text Available We review oxidative stress-related newborn disease and the mechanism of oxidative damage. In addition, we outline diagnostic and therapeutic strategies and future directions. Many reports have defined oxidative stress as an imbalance between an enhanced reactive oxygen/nitrogen species and the lack of protective ability of antioxidants. From that point of view, free radical-induced damage caused by oxidative stress seems to be a probable contributing factor to the pathogenesis of many newborn diseases, such as respiratory distress syndrome, bronchopulmonary dysplasia, periventricular leukomalacia, necrotizing enterocolitis, patent ductus arteriosus, and retinopathy of prematurity. We share the hope that the new understanding of the concept of oxidative stress and its relation to newborn diseases that has been made possible by new diagnostic techniques will throw light on the treatment of those diseases.
Briganti, S; Cristaudo, A; D'Argento, V; Cassano, N; Turbino, L; Guarrera, M; Vena, G; Picardo, M
The pathogenesis of the physical urticarias has not been completely defined. Indeed, different stimuli can induce similar clinical manifestations, some of which are capable of generating reactive oxygen species. In order to evaluate whether the generation of an oxidative stress response could be a common pathogenetic mechanism of the disease, we have determined the profile of a number of chemical and enzymatic antioxidants in blood samples from a group of patients with physical urticarias. Compared with controls, a systemic imbalance of the antioxidants was detected in the patient group with a decrease of both plasma vitamin E and cellular catalase and glutathione peroxidase activities along with an increase of superoxide dismutase activity. Moreover, an increase in the percentage of plasma polyunsaturated fatty acids, as a target for peroxidative damage, was also observed. These alterations may lead to an increased percentage of peroxidable compounds in skin and to the intracellular generation of reactive oxygen species and could therefore provide one possible explanation for the patients' urticarial response to stimuli. Even if the alteration of the antioxidant status is secondary to changes in cytokine or complement activation, our results suggest a common biochemical profile in patients with different forms of physical urticaria.
Particulate matter (PM), a component of air pollution has been epidemiologically associated with sudden deaths, cardiovascular and respiratory illnesses. The effects are more pronounced in patients with pre-existing conditions such as asthma, diabetes or obstructive pulmonary disorders. Clinical and experimental studies have historically focused on the cardiopulmonary effects of PM. However, since PM particles carry numerous biocontaminants that are capable of triggering free radical production and cytokine release, the possibility that PM may affect organs systems sensitive to oxidative stress must be considered. Four independent studies that summarize the neurochemical and neuropathological changes found in the brains of PM exposed animals are described here. These were recently presented at two 2007 symposia sponsored by the Society of Toxicology (Charlotte, NC) and the International Neurotoxicology Association (Monterey, CA). Particulates are covered with biocontaminants (e.g., endotoxins, mold, pollen) which convey free radical activity that can damage the lipids, nucleic acids, and proteins of target cells on contact and stimulate inflammatory cytokine release. Although, the historical focus of PM toxicity has been cardiopulmonary targets, it is now appreciated that inhaled nano-size (<100 nm) particles quickly exit the lungs and enter the circulation where they distribute to various organ systems (l.e., liver, kidneys, testes, lymph nodes) (Takenaka et aI
Kästle, Marc; Reeg, Sandra; Rogowska-Wrzesinska, Adelina
After oxidative stress proteins which are oxidatively modified are degraded by the 20S proteasome. However, several studies documented an enhanced ubiquitination of yet unknown proteins. Since ubiqutination is a prerequisite for degradation by the 26S proteasome in an ATP-dependent manner...... this raises the question whether these proteins are also oxidized and, if not, what proteins need to be ubiquitinated and degraded after oxidative conditions. By determination of oxidized- and ubiquitinated proteins we demonstrate here that most oxidized proteins are not preferentially ubiquitinated. However......, we were able to confirm an increase of ubiquitinated proteins 16h upon oxidative stress. Therefore, we isolated ubiquitinated proteins from hydrogen peroxide treated cells, as well as from control and lactacystin, an irreversible proteasome inhibitor, treated cells, and identified some...
Full Text Available Abstract Background Accumulation of aberrant proteins to form Lewy bodies (LBs is a hallmark of Parkinson's disease (PD. Ubiquitination-mediated degradation of aberrant, misfolded proteins is critical for maintaining normal cell function. Emerging evidence suggests that oxidative/nitrosative stress compromises the precisely-regulated network of ubiquitination in PD, particularly affecting parkin E3 ligase activity, and contributes to the accumulation of toxic proteins and neuronal cell death. Results To gain insight into the mechanism whereby cell stress alters parkin-mediated ubiquitination and LB formation, we investigated the effect of oxidative stress. We found significant increases in oxidation (sulfonation and subsequent aggregation of parkin in SH-SY5Y cells exposed to the mitochondrial complex I inhibitor 1-methyl-4-phenlypyridinium (MPP+, representing an in vitro cell-based PD model. Exposure of these cells to direct oxidation via pathological doses of H2O2 induced a vicious cycle of increased followed by decreased parkin E3 ligase activity, similar to that previously reported following S-nitrosylation of parkin. Pre-incubation with catalase attenuated H2O2 accumulation, parkin sulfonation, and parkin aggregation. Mass spectrometry (MS analysis revealed that H2O2 reacted with specific cysteine residues of parkin, resulting in sulfination/sulfonation in regions of the protein similar to those affected by parkin mutations in hereditary forms of PD. Immunohistochemistry or gel electrophoresis revealed an increase in aggregated parkin in rats and primates exposed to mitochondrial complex I inhibitors, as well as in postmortem human brain from patients with PD with LBs. Conclusion These findings show that oxidative stress alters parkin E3 ligase activity, leading to dysfunction of the ubiquitin-proteasome system and potentially contributing to LB formation.
Espejo, C.; Penkowa, Milena; Saez-Torres, I.
Neurobiology, experimental autoimmune encephalomyelitis IFN-d, multiple sclerosis, neurodegeneration, oxidative stress......Neurobiology, experimental autoimmune encephalomyelitis IFN-d, multiple sclerosis, neurodegeneration, oxidative stress...
Vitale, Giovanni; Salvioli, Stefano; Franceschi, Claudio
Ageing is a process characterized by a progressive decline in cellular function, organismal fitness and increased risk of age-related diseases and death. Several hundred theories have attempted to explain this phenomenon. One of the most popular is the 'oxidative stress theory', originally termed the 'free radical theory'. The endocrine system seems to have a role in the modulation of oxidative stress; however, much less is known about the role that oxidative stress might have in the ageing of the endocrine system and the induction of age-related endocrine diseases. This Review outlines the interactions between hormones and oxidative metabolism and the potential effects of oxidative stress on ageing of endocrine organs. Many different mechanisms that link oxidative stress and ageing are discussed, all of which converge on the induction or regulation of inflammation. All these mechanisms, including cell senescence, mitochondrial dysfunction and microRNA dysregulation, as well as inflammation itself, could be targets of future studies aimed at clarifying the effects of oxidative stress on ageing of endocrine glands.
Wang, Yue; Andrukhov, Oleh; Rausch-Fan, Xiaohui
Periodontitis is a common inflammatory disease, which is initiated by bacterial infection and subsequently progressed by aberrant host response. It can result in the destruction of teeth supporting tissues and have an influence on systemic health. When periodontitis occurs, reactive oxygen species, which are overproduced mostly by hyperactive neutrophils, could not be balanced by antioxidant defense system and cause tissues damage. This is characterized by increased metabolites of lipid peroxidation, DNA damage and protein damage. Local and systemic activities of antioxidants can also be influenced by periodontitis. Total antioxidant capacity, total oxidant status and oxidative stress index have been used to evaluate the oxidative stress associated with periodontitis. Studies have confirmed that inflammatory response in periodontitis is associated with an increased local and systemic oxidative stress and compromised antioxidant capacity. Our review focuses on increased oxidative stress in periodontal disease, specifically, on the relationship between the local and systemic biomarkers of oxidative stress and periodontitis and their association with the pathogenesis of periodontitis. Also, the relationship between periodontitis and systemic inflammation, and the effects of periodontal therapy on oxidative stress parameters will be discussed. PMID:29180965
Hypogonadism attributable to males with metabolic syndrome was also observed in automechanics occupationally exposed to mixed chemicals accompanied by oxidative stress (OS). We evaluated associations among testosterone, OS biomarkers, enzymatic and non-enzymatic antioxidants in normal weight ...
Rasmussen, Sanne Tofte; Andersen, Jon Thor Trærup; Nielsen, Torben Kjær
Simvastatin reduces the blood concentration of cholesterol by inhibiting hydroxymethylglutaryl-coenzyme A reductase, the rate-limiting enzyme in cholesterol synthesis, and thereby reduces the risk of cardiovascular disease. In addition, simvastatin treatment leads to a reduction in fluxes in mito...... in diseased populations, such as diabetes or hemochromatosis, where oxidative stress is prominent, is unknown but seems unlikely....... in mitochondrial respiratory complexes I and II and might thereby reduce the formation of reactive oxygen species, which have been implicated in the pathogenesis of arteriosclerosis. Therefore, we hypothesized that simvastatin may reduce oxidative stress in humans in vivo. We conducted a randomized, double......-blinded, placebo-controlled study in which subjects were treated with either 40 mg of simvastatin or placebo for 14 days. The endpoints were six biomarkers for oxidative stress, which represent intracellular oxidative stress to nucleic acids, lipid peroxidation and plasma antioxidants, that were measured in urine...
Feb 14, 2012 ... Oxidative stress has been implicated in coronary artery disease (CAD). Malondialdehyde (MDA) is lipid peroxidation end product. Bilirubin may act as an antioxidant that suppresses lipid oxidation. The role of MDA and antioxidant capacity and their inter-relationship in patients with and without CAD was.
Upham, B L; Wagner, J G
The article highlighted in this issue is "The Role of Oxidative Stress in Indium Phosphide-Induced Lung Carcinogenesis in Rats" by Barbara C. Gottschling, Robert R. Maronpot, James R. Hailey, Shyamal Peddada, Cindy R. Moomaw, James E. Klaunig, and Abraham Nyska (pp. 28-40). The article integrates a traditional pathologic study of toxicant-induced pulmonary carcinogenesis with an immunohistologic assessment of oxidative stress, thereby determining a potential mechanism of action of a toxicant, specifically indium phosphide.
Hovatta, Iiris; Juhila, Juuso; Donner, Jonas
Anxiety disorders, depression, and alcohol use disorder are common neuropsychiatric diseases that often occur together. Oxidative stress has been suggested to contribute to their etiology. Oxidative stress is a consequence of either increased generation of reactive oxygen species or impaired enzymatic or non-enzymatic defense against it. When excessive it leads to damage of all major classes of macromolecules, and therefore affects several fundamentally important cellular functions. Consequences that are especially detrimental to the proper functioning of the brain include mitochondrial dysfunction, altered neuronal signaling, and inhibition of neurogenesis. Each of these can further contribute to increased oxidative stress, leading to additional burden to the brain. In this review, we will provide an overview of recent work on oxidative stress markers in human patients with anxiety, depressive, or alcohol use disorders, and in relevant animal models. In addition, putative oxidative stress-related mechanisms important for neuropsychiatric diseases are discussed. Despite the considerable interest this field has obtained, the detailed mechanisms that link oxidative stress to the pathogenesis of neuropsychiatric diseases remain largely unknown. Since this pathway may be amenable to pharmacological intervention, further studies are warranted. Copyright © 2010 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.
Full Text Available The ocular surface is always attacked by oxidative stress, and cornea epithelial cells are supposed to have their own recovery system against oxidative stress. Therefore we hypothesized that tears supply key molecules for preventing oxidative stress in cornea. The potential target key molecule we focused is selenoprotein P (SeP. SeP is a carrier of selenium, which is an essential trace element for many animals, for oxidative stress metabolism in the organism, and was extremely expressed in lacrimal gland. An experiment was performed with SeP eye drops in a rat dry eye model, prepared by removing the lacrimal glands. The anticipated improvement in corneal dry eye index and the suppression of oxidative stress markers were observed in SeP eye drop group. Furthermore, the concentration of SeP was significantly higher in dry eye patients compared with normal volunteers. Collectively, we concluded that tear SeP is a key molecule to protect the ocular surface cells against environmental oxidative stress.
Bloomer, Richard J; Goldfarb, Allen H
Oxidative stress and subsequent damage to cellular proteins, lipids, and nucleic acids, as well as changes to the glutathione system, are well documented in response to aerobic exercise. However, far less information is available on anaerobic exercise-induced oxidative modifications. Recent evidence indicates that high intensity anaerobic work does result in oxidative modification to the above-mentioned macromolecules in both skeletal muscle and blood. Also, it appears that chronic anaerobic exercise training can induce adaptations that act to attenuate the exercise-induced oxidative stress. These may be specific to increased antioxidant defenses and/or may act to reduce the generation of pro-oxidants during and after exercise. However, a wide variety of exercise protocols and assay procedures have been used to study oxidative stress pertaining to anaerobic work. Therefore, precise conclusions about the exact extent and location of oxidative macromolecule damage, in addition to the adaptations resulting from chronic anaerobic exercise training, are difficult to indicate. This manuscript provides a review of anaerobic exercise and oxidative stress, presenting both the acute effects of a single exercise bout and the potential for adaptations resulting from chronic anaerobic training.
Malinin, Nikolay L.; West, Xiaoxia Z.; Byzova, Tatiana V.
Multiple biological consequences of oxidative stress are known to contribute to aging and aging-related pathologies. It was recently shown that (carboxyalkyl)pyrroles (CAPs), the end products of phospholipid oxidation serve as a novel class of endogenous ligands for Toll-like receptors (TLRs) and promote the process of angiogenesis. In this review, we discuss implications of these findings in the context of age-related pathologies, including tumorigenesis. Accumulation of oxidation products i...
Peivandi Yazdi A
Full Text Available Free radical and peroxide production lead to intracellular damage. On the other hand, free radicals are used by the human immune system to defend against pathogens. The aging process could be limited by oxidative stress in the short term. Chronic diseases like diabetes mellitus (DM are full-stress conditions in which remarkable metabolic functional destructions might happen. There is strong evidence regarding antioxidant impairment in diabetes. Performing a particular method for anesthesia in diabetic patients might prevent or modify excessive free radical formation and oxidative stress. It seems that prescribing antioxidant drugs could promote wound healing in diabetics.
Rinnerthaler, Mark; Bischof, Johannes; Streubel, Maria Karolin; Trost, Andrea; Richter, Klaus
Oxidative stress in skin plays a major role in the aging process. This is true for intrinsic aging and even more for extrinsic aging. Although the results are quite different in dermis and epidermis, extrinsic aging is driven to a large extent by oxidative stress caused by UV irradiation. In this review the overall effects of oxidative stress are discussed as well as the sources of ROS including the mitochondrial ETC, peroxisomal and ER localized proteins, the Fenton reaction, and such enzymes as cyclooxygenases, lipoxygenases, xanthine oxidases, and NADPH oxidases. Furthermore, the defense mechanisms against oxidative stress ranging from enzymes like superoxide dismutases, catalases, peroxiredoxins, and GSH peroxidases to organic compounds such as L-ascorbate, α-tocopherol, beta-carotene, uric acid, CoQ10, and glutathione are described in more detail. In addition the oxidative stress induced modifications caused to proteins, lipids and DNA are discussed. Finally age-related changes of the skin are also a topic of this review. They include a disruption of the epidermal calcium gradient in old skin with an accompanying change in the composition of the cornified envelope. This modified cornified envelope also leads to an altered anti-oxidative capacity and a reduced barrier function of the epidermis. PMID:25906193
Full Text Available Oxidative stress in skin plays a major role in the aging process. This is true for intrinsic aging and even more for extrinsic aging. Although the results are quite different in dermis and epidermis, extrinsic aging is driven to a large extent by oxidative stress caused by UV irradiation. In this review the overall effects of oxidative stress are discussed as well as the sources of ROS including the mitochondrial ETC, peroxisomal and ER localized proteins, the Fenton reaction, and such enzymes as cyclooxygenases, lipoxygenases, xanthine oxidases, and NADPH oxidases. Furthermore, the defense mechanisms against oxidative stress ranging from enzymes like superoxide dismutases, catalases, peroxiredoxins, and GSH peroxidases to organic compounds such as L-ascorbate, α-tocopherol, beta-carotene, uric acid, CoQ10, and glutathione are described in more detail. In addition the oxidative stress induced modifications caused to proteins, lipids and DNA are discussed. Finally age-related changes of the skin are also a topic of this review. They include a disruption of the epidermal calcium gradient in old skin with an accompanying change in the composition of the cornified envelope. This modified cornified envelope also leads to an altered anti-oxidative capacity and a reduced barrier function of the epidermis.
Full Text Available During pregnancy, development of the placenta is interrelated with the oxygen concentration. Embryo development takes place in a low oxygen environment until the beginning of the second trimester when large amounts of oxygen are conveyed to meet the growth requirements. High metabolism and oxidative stress are common in the placenta. Reactive oxidative species sometimes harm placental development, but they are also reported to regulate gene transcription and downstream activities such as trophoblast proliferation, invasion, and angiogenesis. Autophagy and apoptosis are two crucial, interconnected processes in the placenta that are often influenced by oxidative stress. The proper interactions between them play an important role in placental homeostasis. However, an imbalance between the protective and destructive mechanisms of autophagy and apoptosis seems to be linked with pregnancy-related disorders such as miscarriage, preeclampsia, and intrauterine growth restriction. Thus, potential therapies to hold oxidative stress in leash, promote placentation, and avoid unwanted apoptosis are discussed.
Full Text Available Oxidative stress, an imbalance between the generation of reactive oxygen species and antioxidant defense capacity of the body, is closely associated with aging and a number of diseases including cancer, cardiovascular diseases, diabetes and diabetic complications. Several mechanisms may cause oxidative insult in diabetes, although their exact contributions are not entirely clear. Accumulating evidence points to many interrelated mechanisms that increase production of reactive oxygen and nitrogen species or decrease antioxidant protection in diabetic patients. In modern medicine, regular physical exercise is an important tool in the prevention and treatment of diseases including diabetes. Although acute exhaustive exercise increases oxidative stress, exercise training has been shown to up regulate antioxidant protection. This review aims to summarize the mechanisms of increased oxidative stress in diabetes and with respect to acute and chronic exercise
Noah M Walton
Full Text Available An increasing body of evidence suggests that alterations in neurogenesis and oxidative stress are associated with a wide variety of CNS diseases, including Alzheimer's disease, schizophrenia and Parkinson's disease, as well as routine loss of function accompanying aging. Interestingly, the association between neurogenesis and the production of reactive oxidative species (ROS remains largely unexamined. The adult CNS harbors two regions of persistent lifelong neurogenesis: the subventricular zone and the dentate gyrus (DG. These regions contain populations of quiescent neural stem cells (NSCs that generate mature progeny via rapidly-dividing progenitor cells. We hypothesized that the energetic demands of highly proliferative progenitors generates localized oxidative stress that contributes to ROS-mediated damage within the neuropoietic microenvironment. In vivo examination of germinal niches in adult rodents revealed increases in oxidized DNA and lipid markers, particularly in the subgranular zone (SGZ of the dentate gyrus. To further pinpoint the cell types responsible for oxidative stress, we employed an in vitro cell culture model allowing for the synchronous terminal differentiation of primary hippocampal NSCs. Inducing differentiation in primary NSCs resulted in an immediate increase in total mitochondria number and overall ROS production, suggesting oxidative stress is generated during a transient window of elevated neurogenesis accompanying normal neurogenesis. To confirm these findings in vivo, we identified a set of oxidation-responsive genes, which respond to antioxidant administration and are significantly elevated in genetic- and exercise-induced model of hyperactive hippocampal neurogenesis. While no direct evidence exists coupling neurogenesis-associated stress to CNS disease, our data suggest that oxidative stress is produced as a result of routine adult neurogenesis.
Slade, Dea; Radman, Miroslav
Summary: Deinococcus radiodurans is a robust bacterium best known for its capacity to repair massive DNA damage efficiently and accurately. It is extremely resistant to many DNA-damaging agents, including ionizing radiation and UV radiation (100 to 295 nm), desiccation, and mitomycin C, which induce oxidative damage not only to DNA but also to all cellular macromolecules via the production of reactive oxygen species. The extreme resilience of D. radiodurans to oxidative stress is imparted synergistically by an efficient protection of proteins against oxidative stress and an efficient DNA repair mechanism, enhanced by functional redundancies in both systems. D. radiodurans assets for the prevention of and recovery from oxidative stress are extensively reviewed here. Radiation- and desiccation-resistant bacteria such as D. radiodurans have substantially lower protein oxidation levels than do sensitive bacteria but have similar yields of DNA double-strand breaks. These findings challenge the concept of DNA as the primary target of radiation toxicity while advancing protein damage, and the protection of proteins against oxidative damage, as a new paradigm of radiation toxicity and survival. The protection of DNA repair and other proteins against oxidative damage is imparted by enzymatic and nonenzymatic antioxidant defense systems dominated by divalent manganese complexes. Given that oxidative stress caused by the accumulation of reactive oxygen species is associated with aging and cancer, a comprehensive outlook on D. radiodurans strategies of combating oxidative stress may open new avenues for antiaging and anticancer treatments. The study of the antioxidation protection in D. radiodurans is therefore of considerable potential interest for medicine and public health. PMID:21372322
Slade, Dea; Radman, Miroslav
Deinococcus radiodurans is a robust bacterium best known for its capacity to repair massive DNA damage efficiently and accurately. It is extremely resistant to many DNA-damaging agents, including ionizing radiation and UV radiation (100 to 295 nm), desiccation, and mitomycin C, which induce oxidative damage not only to DNA but also to all cellular macromolecules via the production of reactive oxygen species. The extreme resilience of D. radiodurans to oxidative stress is imparted synergistically by an efficient protection of proteins against oxidative stress and an efficient DNA repair mechanism, enhanced by functional redundancies in both systems. D. radiodurans assets for the prevention of and recovery from oxidative stress are extensively reviewed here. Radiation- and desiccation-resistant bacteria such as D. radiodurans have substantially lower protein oxidation levels than do sensitive bacteria but have similar yields of DNA double-strand breaks. These findings challenge the concept of DNA as the primary target of radiation toxicity while advancing protein damage, and the protection of proteins against oxidative damage, as a new paradigm of radiation toxicity and survival. The protection of DNA repair and other proteins against oxidative damage is imparted by enzymatic and nonenzymatic antioxidant defense systems dominated by divalent manganese complexes. Given that oxidative stress caused by the accumulation of reactive oxygen species is associated with aging and cancer, a comprehensive outlook on D. radiodurans strategies of combating oxidative stress may open new avenues for antiaging and anticancer treatments. The study of the antioxidation protection in D. radiodurans is therefore of considerable potential interest for medicine and public health.
Vacaresse, Nathalie; Vieira, Otília; Robbesyn, Fanny; Jürgens, Günther; Salvayre, Robert; Negre-Salvayre, Anne
Oxidized low density lipoproteins (oxLDL) are thought to play a major role in atherosclerosis. OxLDL act in part through alteration of intracellular signalling pathways in cells of the vascular wall. We recently reported that the EGF receptor (EGFR) signalling pathway is activated by lipid peroxidation products (among them 4-hydroxynonenal, 4-HNE) contained in oxLDL.The use of phenolic antioxidants, such as trolox, alpha-tocopherol, caffeic acid and tyrphostins A-25, A-46 or A-1478, showed that the oxLDL-induced EGFR activation is constituted by two separate components, the first (early) one being antioxidant-insensitive, the second (late) being antioxidant-sensitive.4-HNE derivatization of EGFR and EGFR activation induced by exogenous 4-HNE, suggest that the early (0.5 – 3 h) component of oxLDL-induced EGFR activation is mediated (at least in part) by 4-HNE (and possibly by other oxidized lipids). This early component is antioxidant-insensitive.The second component (4 – 5 h) of the oxLDL-induced EGFR activation is antioxidant-sensitive, since it is blocked by antioxidants such as trolox, caffeic acid or PDTC, which act by blocking the cellular oxidative stress (H2O2 generation) evoked by oxLDL. Conversely, exogenous H2O2 induced EGFR autophosphorylation (thus mimicking the second component) and was also inhibited by antioxidants. This effect is mediated in part through inhibition by oxidative stress of protein tyrosine phosphatases involved in EGFR dephosphorylation. PMID:11309250
Full Text Available Chronic overnutrition creates chronic hyperglycemia that can gradually induce insulin resistance and insulin secretion impairment. These disorders, if not intervened, will eventually be followed by appearance of frank diabetes. The mechanisms of this chronic pathogenic process are complex but have been suggested to involve production of reactive oxygen species (ROS and oxidative stress. In this review, I highlight evidence that reductive stress imposed by overflux of NADH through the mitochondrial electron transport chain is the source of oxidative stress, which is based on establishments that more NADH recycling by mitochondrial complex I leads to more electron leakage and thus more ROS production. The elevated levels of both NADH and ROS can inhibit and inactivate glyceraldehyde 3-phosphate dehydrogenase (GAPDH, respectively, resulting in blockage of the glycolytic pathway and accumulation of glycerol 3-phospate and its prior metabolites along the pathway. This accumulation then initiates all those alternative glucose metabolic pathways such as the polyol pathway and the advanced glycation pathways that otherwise are minor and insignificant under euglycemic conditions. Importantly, all these alternative pathways lead to ROS production, thus aggravating cellular oxidative stress. Therefore, reductive stress followed by oxidative stress comprises a major mechanism of hyperglycemia-induced metabolic syndrome.
Abscisic acid, H2O2 and nitric oxide interactions mediated cold-induced S-adenosylmethionine synthetase in Medicago sativa subsp. falcata that confers cold tolerance through up-regulating polyamine oxidation.
Guo, Zhenfei; Tan, Jiali; Zhuo, Chunliu; Wang, Congying; Xiang, Bin; Wang, Zengyu
S-adenosylmethionine synthetase (SAMS) is the key enzyme catalysing the formation of S-adenosylmethionine (SAM), a precursor of polyamines and ethylene. To investigate the potential role of SAMS in cold tolerance, we isolated MfSAMS1 from the cold-tolerant germplasm Medicago sativa subsp. falcata and analysed the association of SAM-derived polyamines with cold tolerance. The expression of MfSAMS1 in leaves was greatly induced by cold, abscisic acid (ABA), H2O2 and nitric oxide (NO). Our data revealed that ABA, H2O2 and NO interactions mediated the cold-induced MfSAMS1 expression and cold acclimation in falcata. SAM, putrescine, spermidine and spermine levels, ethylene production and polyamine oxidation were sequentially altered in response to cold, indicating that SAMS-derived SAM is preferentially used in polyamine synthesis and homeostasis during cold acclimation. Antioxidant enzyme activities were also induced in response to cold and showed correlation with polyamine oxidation. Overexpression of MfSAMS1 in tobacco resulted in elevated SAM levels, but polyamine levels and ethylene production in the transgenic plants were not significantly changed. Compared to the wild type, transgenic plants had increased levels of apoplastic H2O2, higher transcript levels of genes involved in polyamine synthesis and oxidation, and higher activities of polyamine oxidation and antioxidant enzymes. The results showed that overexpression of MfSAMS1 promoted polyamine synthesis and oxidation, which in turn improved H2 O2 -induced antioxidant protection, as a result enhanced tolerance to freezing and chilling stress in transgenic plants. This is the first report demonstrating that SAMS plays an important role in plant tolerance to cold via up-regulating polyamine oxidation. © 2014 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.
Chaudhari, Namrata; Talwar, Priti; Parimisetty, Avinash; Lefebvre d’Hellencourt, Christian; Ravanan, Palaniyandi
Execution of fundamental cellular functions demands regulated protein folding homeostasis. Endoplasmic reticulum (ER) is an active organelle existing to implement this function by folding and modifying secretory and membrane proteins. Loss of protein folding homeostasis is central to various diseases and budding evidences suggest ER stress as being a major contributor in the development or pathology of a diseased state besides other cellular stresses. The trigger for diseases may be diverse but, inflammation and/or ER stress may be basic mechanisms increasing the severity or complicating the condition of the disease. Chronic ER stress and activation of the unfolded-protein response (UPR) through endogenous or exogenous insults may result in impaired calcium and redox homeostasis, oxidative stress via protein overload thereby also influencing vital mitochondrial functions. Calcium released from the ER augments the production of mitochondrial Reactive Oxygen Species (ROS). Toxic accumulation of ROS within ER and mitochondria disturbs fundamental organelle functions. Sustained ER stress is known to potentially elicit inflammatory responses via UPR pathways. Additionally, ROS generated through inflammation or mitochondrial dysfunction could accelerate ER malfunction. Dysfunctional UPR pathways have been associated with a wide range of diseases including several neurodegenerative diseases, stroke, metabolic disorders, cancer, inflammatory disease, diabetes mellitus, cardiovascular disease, and others. In this review, we have discussed the UPR signaling pathways, and networking between ER stress-induced inflammatory pathways, oxidative stress, and mitochondrial signaling events, which further induce or exacerbate ER stress. PMID:25120434
Full Text Available Cardiovascular disease (CVD is the leading cause of morbidity and mortality among patients with diabetes mellitus (DM. DM can lead to multiple cardiovascular complications, including coronary artery disease (CAD, cardiac hypertrophy, and heart failure (HF. HF represents one of the most common causes of death in patients with DM and results from DM-induced CAD and diabetic cardiomyopathy. Oxidative stress is closely associated with the pathogenesis of DM and results from overproduction of reactive oxygen species (ROS. ROS overproduction is associated with hyperglycemia and metabolic disorders, such as impaired antioxidant function in conjunction with impaired antioxidant activity. Long-term exposure to oxidative stress in DM induces chronic inflammation and fibrosis in a range of tissues, leading to formation and progression of disease states in these tissues. Indeed, markers for oxidative stress are overexpressed in patients with DM, suggesting that increased ROS may be primarily responsible for the development of diabetic complications. Therefore, an understanding of the pathophysiological mechanisms mediated by oxidative stress is crucial to the prevention and treatment of diabetes-induced CVD. The current review focuses on the relationship between diabetes-induced CVD and oxidative stress, while highlighting the latest insights into this relationship from findings on diabetic heart and vascular disease.
Full Text Available Comparison of oxidative stress status between subjects with or without warts is absent in the literature. In this study, we evaluated 31 consecutive patients with warts (15 female, 16 male and 36 control cases with no evidence of disease to determine the effects of oxidative stress in patients with warts. The patients were classified according to the wart type, duration, number, and location of lesions. We measured the indicators of oxidative stress such as catalase (CAT, glucose-6-phosphate dehydrogenase (G6PD, superoxide dismutase (SOD, and malondialdehyde (MDA in the venous blood by spectrophotometry. There was a statistically significant increase in levels of CAT, G6PD, SOD activities and MDA in the patients with warts compared to the control group (P<.05. However, we could not define a statistically significant correlation between these increased enzyme activities and MDA levels and the type, the duration, the number, and the location of lesions. We determined possible suppression of T cells during oxidative stress that might have a negative effect on the prognosis of the disease. Therefore, we propose an argument for the appropriateness to give priority to immunomodulatory treatment alternatives instead of destructive methods in patients with demonstrated oxidative stress.
Camini, Fernanda Caetano; da Silva Caetano, Camila Carla; Almeida, Letícia Trindade; da Costa Guerra, Joyce Ferreira; de Mello Silva, Breno; de Queiroz Silva, Silvana; de Magalhães, José Carlos; de Brito Magalhães, Cintia Lopes
Mayaro virus (MAYV) is a neglected tropical arbovirus that causes a febrile syndrome that is sometimes accompanied by incapacitating arthritis/arthralgia. The pathogenesis of MAYV has not been completely defined and oxidative stress mediated by an increase in reactive oxygen species (ROS) and/or depletion of antioxidant defences has been found to contribute to several aspects of viral disease. To investigate whether MAYV induced oxidative stress in host cells, we monitored ROS production, oxidative stress markers and antioxidant defences at different time points after infection. Our results show that MAYV induced significant oxidative stress in infected HepG2 cells, as indicated by the increase of malondialdehyde (MDA) and protein carbonyl levels, and by a significant decrease of the reduced versus oxidized glutathione (GSH/GSSG) ratio. Generally, MAYV-infected HepG2 cells also showed an increase in antioxidant defences. We observed an increase in the superoxide dismutase (SOD) and catalase (CAT) activities and the total glutathione content. To determine whether similar effects occurred in other cell types, we evaluated the ROS, MDA and SOD activity levels in J774 cells after MAYV infection. Similar to our observations in HepG2 cells, the J774 cells showed an increase in ROS, MDA and total SOD activity following MAYV infection. Thus, since the cellular redox environment is influenced by the production and removal of ROS, we hypothesize that the overproduction of ROS was responsible for the oxidative stress in response to the MAYV infection despite the increase in the antioxidant status. This study is the first report on the involvement of oxidative stress during MAYV infection. Collectively, our data shed light on some mechanisms that are operational in host cells following exposure to MAYV. Copyright © 2017 Elsevier B.V. All rights reserved.
Full Text Available Mono-ubiquitinated PCNA activates error-prone DNA polymerases; therefore, strict regulation of PCNA mono-ubiquitination is crucial in avoiding undesired mutagenesis. In this study, we used an in vitro assay system to identify USP7 as a deubiquitinating enzyme of mono-ubiquitinated PCNA. Suppression of USP1, a previously identified PCNA deubiquitinase, or USP7 increased UV- and H2O2-induced PCNA mono-ubiquitination in a distinct and additive manner, suggesting that USP1 and USP7 make different contributions to PCNA deubiquitination in human cells. Cell-cycle-synchronization analyses revealed that USP7 suppression increased H2O2-induced PCNA ubiquitination throughout interphase, whereas USP1 suppression specifically increased ubiquitination in S-phase cells. UV-induced mutagenesis was elevated in USP1-suppressed cells, whereas H2O2-induced mutagenesis was elevated in USP7-suppressed cells. These results suggest that USP1 suppresses UV-induced mutations produced in a manner involving DNA replication, whereas USP7 suppresses H2O2-induced mutagenesis involving cell-cycle-independent processes such as DNA repair.
Henry, Leroy G; McKenzie, Rachelle ME; Robles, Antonette; Fletcher, Hansel M
Porphyromonas gingivalis, a black-pigmented, Gram-negative anaerobe, is an important etiologic agent of periodontal disease. The harsh inflammatory condition of the periodontal pocket implies that this organism has properties that will facilitate its ability to respond and adapt to oxidative stress. Because the stress response in the pathogen is a major determinant of its virulence, a comprehensive understanding of its oxidative stress resistance strategy is vital. We discuss multiple mechanisms and systems that clearly work in synergy to defend and protect P. gingivalis against oxidative damage caused by reactive oxygen species. The involvement of multiple hypothetical proteins and/or proteins of unknown function in this process may imply other unique mechanisms and potential therapeutic targets. PMID:22439726
Atalay, Mustafa; Laaksonen, David E.
Oxidative stress, an imbalance between the generation of reactive oxygen species and antioxidant defense capacity of the body, is closely associated with aging and a number of diseases including cancer, cardiovascular diseases, diabetes and diabetic complications. Several mechanisms may cause oxidative insult in diabetes, although their exact contributions are not entirely clear. Accumulating evidence points to many interrelated mechanisms that increase production of reactive oxygen and nitro...
Dursun, Erhan; Akalin, Ferda Alev; Genc, Tolga; Cinar, Nese; Erel, Ozcan; Yildiz, Bulent Okan
Periodontal disease is a chronic inflammatory disease of the jaws and is more prevalent in obesity. Local and systemic oxidative stress may be an early link between periodontal disease and obesity. The primary aim of this study was to detect whether increased periodontal disease susceptibility in obese individuals is associated with local and systemic oxidative stress. Accordingly; we analyzed periodontal status and systemic (serum) and local (gingival crevicular fluid [GCF]) oxidative status markers in young obese women in comparison with age-matched lean women.Twenty obese and 20 lean women participated. Periodontal condition was determined by clinical periodontal indices including probing depth, clinical attachment level, gingival index, gingival bleeding index, and plaque index. Anthropometric, hormonal, and metabolic measurements were also performed. Blood and GCF sampling was performed at the same time after an overnight fasting. Serum and GCF total antioxidant capacity (TAOC), and total oxidant status (TOS) levels were determined, and oxidative stress index (OSI) was calculated.Clinical periodontal analyses showed higher gingival index and gingival bleeding index in the obese group (P = 0.001 for both) with no significant difference in probing depth, clinical attachment level, and plaque index between the obese and the lean women. Oxidant status analyses revealed lower GCF and serum TAOC, and higher GCF and serum OSI values in the obese women (P periodontal indices showed significant correlations with body mass index, insulin, and lipid levels, and also oxidant status markers.Our results suggest that young obese, otherwise healthy, women show findings of early periodontal disease (gingival inflammation) compared with age-matched healthy lean women, and that local/periodontal oxidative stress generated by obesity seems to be associated with periodontal disease.
Jenkins, R R; Goldfarb, A
In recent years research in the basic and applied sciences has broadened our understanding of oxygen chemistry and its influences on biological systems. Although living organisms are endowed with a broad array of biochemical defense mechanisms for protection against potentially harmful radical chemistry, oxidative stress may overwhelm those defenses. It is now clear that exercise may initiate oxidative stress. It is the aim of this symposium to review and broaden our understanding of the problem of free radical chemistry as it applies to the exercise milieu.
Wilfredo Mañon Rossi
Full Text Available Biomarkers are used regularly in medical practice to provide objective markers of health status of a person, as well as the physiological response of the body to a pharmacological therapeutic intervention. In the specific case of the use of antioxidant products (antioxidant therapy, it is necessary to measure both biomarkers of oxidative stress level of the person as those that are specific to a physiological or pathological progression of a disease disorder. This paper describes the main biomarkers of oxidative general and specific stress as well as laboratory techniques, which should be taken into account when measuring the effectiveness of antioxidant therapies.
Brain ischemia initiates a complex cascade of metabolic events, several of which involve the generation of nitrogen and oxygen free radicals. These free radicals and related reactive chemical species mediate much of damage that occurs after transient brain ischemia, and in the penumbral region of infarcts caused by permanent ischemia. Nitric oxide, a water- and lipid-soluble free radical, is generated by the action of nitric oxide synthases. Ischemia causes a surge in nitric oxide synthase 1 (NOS 1) activity in neurons and, possibly, glia, increased NOS 3 activity in vascular endothelium, and later an increase in NOS 2 activity in a range of cells including infiltrating neutrophils and macrophages, activated microglia and astrocytes. The effects of ischemia on the activity of NOS 1, a Ca2+-dependent enzyme, are thought to be secondary to reversal of glutamate reuptake at synapses, activation of NMDA receptors, and resulting elevation of intracellular Ca2+. The up-regulation of NOS 2 activity is mediated by transcriptional inducers. In the context of brain ischemia, the activity of NOS 1 and NOS 2 is broadly deleterious, and their inhibition or inactivation is neuroprotective. However, the production of nitric oxide in blood vessels by NOS 3, which, like NOS 1, is Ca2+-dependent, causes vasodilatation and improves blood flow in the penumbral region of brain infarcts. In addition to causing the synthesis of nitric oxide, brain ischemia leads to the generation of superoxide, through the action of nitric oxide synthases, xanthine oxidase, leakage from the mitochondrial electron transport chain, and other mechanisms. Nitric oxide and superoxide are themselves highly reactive but can also combine to form a highly toxic anion, peroxynitrite. The toxicity of the free radicals and peroxynitrite results from their modification of macromolecules, especially DNA, and from the resulting induction of apoptotic and necrotic pathways. The mode of cell death that prevails probably
Desireddy Neelima, Bandi Hari Krishna, Masthan Saheb, Natham Mallikarjuna Reddy.
Full Text Available Background and objectives: Pellagra was vanished from most parts of the world where it was formerly present due to its dietary modification. However, it is still encountered among the jowar eating populations of India. The information about the role of oxidative stress in pellagra was not established. Therefore, in this study we assessed the oxidative stress status by using malondialdehyde (MDA, total anti oxidant status (TAOS and redox ratio (RER in clinically diagnosed pellagra patients. Materials and methods: Clinically diagnosed pellagra patients aged between 18 to 40 years, both male and females were recruited (n=78 from department of Dermatology. Age and gender matched controls (n=78 were recruited from the student and residents of the hospital. Malondialdehyde (MDA is a marker of lipid peroxidation, Total Anti Oxidant Status (TAOS and Redox Ratio (RER markers were assessed by using commercially available kits. Results: There were no significant differences in the anthropometric parameters. However, the oxidative stress markers MDA (p<0.05, RER (p<0.001 were significantly high and TAOS was low (P<0.001 in pellagra patients in comparison with age and gender matched controls. Conclusion: The results of this study showed the increased MDA, RER levels and decreased TAOS levels. Estimation of these markers at early stage will help to take measures to prevent the progression of disease and develop antioxidant strategies.
Prasad, Rajniti; Anil; Mishra, Om P; Mishra, Surendra P; Upadhyay, Ram S; Singh, Tej B
Free radicals can cause neuronal injury and play an important role in pathogenesis of neurocysticercosis. This study was done to evaluate oxidative stress (antioxidants and oxidants) in cerebrospinal fluid (CSF) of children with neurocysticercosis and to observe their correlation with the type of seizure and outcome. Forty consecutive confirmed cases of neurocysticercosis were evaluated for their markers of reactive oxygen species, that is, oxidants (malondialdehyde, protein carbonyl and nitrite) and antioxidant (superoxide dismutase, glutathione peroxidase, ceruloplasmin, ascorbic acid, copper and zinc) concentrations in CSF. An equal number of children, age and sex matched with an idiopathic generalized tonic-clonic seizure, were studied as controls. Generalized tonic-clonic seizure (65%) was the most common presentation, and a single ring-enhancing lesion in the parietal lobe was the most common finding in cranial imaging. Oxidants such as malondialdehyde, protein carbonyl and nitrite in CSF were significantly elevated (P neurocysticercosis than in controls. There were insignificant differences in oxidant and antioxidant value in CSF in relation to the type of seizure, number and location of lesion in cerebral cortex and antiepileptic therapy. The significantly elevated malondialdehyde, nitrite and protein carbonyl values reflect increased oxidative stress, whereas decreased concentrations of glutathione peroxidase, ascorbic acid, zinc, copper, ceruloplasmin and superoxide dismutase point toward utilization of the antioxidants in neurocysticercosis. The observed changes in oxidants and antioxidants suggest the production of reactive oxygen species such as superoxide, hydrogen peroxides and hydroxyl radicals and their possible role in pathogenesis of neurocysticercosis.
Malinin, Nikolay L; West, Xiaoxia Z; Byzova, Tatiana V
Multiple biological consequences of oxidative stress are known to contribute to aging and aging-related pathologies. It was recently shown that (carboxyalkyl)pyrroles (CAPs), the end products of phospholipid oxidation serve as a novel class of endogenous ligands for Toll-like receptors (TLRs) and promote the process of angiogenesis. In this review, we discuss implications of these findings in the context of age-related pathologies, including tumorigenesis. Accumulation of oxidation products in tissues of aging organisms might create conditions for uncontrolled pathological angiogenesis as seen in patients with age related macular degeneration. CAPs and their receptors, TLRs might also promote the progression of atherosclerotic lesions. Importantly, besides their role in a number of pathologies, oxidative products of phospholipids contribute to tissue repair processes thereby antagonizing the destructive effects of oxidation.
Hepatic Antioxidant, Oxidative Stress And Histopathological Changes Induced By Nicotine In A Gender Based Study In Adult Rats. ... In comparison with the control findings of male and female rats, nicotine-treated male and female rats showed significant increase in MDA content by 57.3 and 41.8% respectively and a ...
Background: Diabetes mellitus (DM) is known to induce oxidative stress along with deranging various metabolisms; one of the late complications of .... History and physical data were obtained from both groups of cases and controls. Systolic ... disorders, cardiac diseases, stroke, gestational. DM, and complications related to ...
Background: Methyl-thiophanate (MT), a fungicide largely used in agriculture throughout the world including Tunisia, protects many vegetables, fruits and field crops against a wide spectrum of fungal diseases. Oxidative stress has been proposed as a possible mechanism involved in MT toxicity on non-target organism.
Berg, Ronan M G; Møller, Kirsten; Bailey, Damian M
Neuro-oxidative-nitrosative stress may prove the molecular basis underlying brain dysfunction in sepsis. In the current review, we describe how sepsis-induced reactive oxygen and nitrogen species (ROS/RNS) trigger lipid peroxidation chain reactions throughout the cerebrovasculature and surrounding...
Full Text Available Age-related neurodegenerative disease has been mechanistically linked with mitochondrial dysfunction via damage from reactive oxygen species produced within the cell. We determined whether increased mitochondrial oxidative stress could modulate or regulate two of the key neurochemical hallmarks of Alzheimer's disease (AD: tau phosphorylation, and beta-amyloid deposition. Mice lacking superoxide dismutase 2 (SOD2 die within the first week of life, and develop a complex heterogeneous phenotype arising from mitochondrial dysfunction and oxidative stress. Treatment of these mice with catalytic antioxidants increases their lifespan and rescues the peripheral phenotypes, while uncovering central nervous system pathology. We examined sod2 null mice differentially treated with high and low doses of a catalytic antioxidant and observed striking elevations in the levels of tau phosphorylation (at Ser-396 and other phospho-epitopes of tau in the low-dose antioxidant treated mice at AD-associated residues. This hyperphosphorylation of tau was prevented with an increased dose of the antioxidant, previously reported to be sufficient to prevent neuropathology. We then genetically combined a well-characterized mouse model of AD (Tg2576 with heterozygous sod2 knockout mice to study the interactions between mitochondrial oxidative stress and cerebral Ass load. We found that mitochondrial SOD2 deficiency exacerbates amyloid burden and significantly reduces metal levels in the brain, while increasing levels of Ser-396 phosphorylated tau. These findings mechanistically link mitochondrial oxidative stress with the pathological features of AD.
Rupérez, Azahara I; Gil, Angel; Aguilera, Concepción M
Obesity is a multifactorial disease characterized by the excessive accumulation of fat in adipose tissue and peripheral organs. Its derived metabolic complications are mediated by the associated oxidative stress, inflammation and hypoxia. Oxidative stress is due to the excessive production of reactive oxygen species or diminished antioxidant defenses. Genetic variants, such as single nucleotide polymorphisms in antioxidant defense system genes, could alter the efficacy of these enzymes and, ultimately, the risk of obesity; thus, studies investigating the role of genetic variations in genes related to oxidative stress could be useful for better understanding the etiology of obesity and its metabolic complications. The lack of existing literature reviews in this field encouraged us to gather the findings from studies focusing on the impact of single nucleotide polymorphisms in antioxidant enzymes, oxidative stress-producing systems and transcription factor genes concerning their association with obesity risk and its phenotypes. In the future, the characterization of these single nucleotide polymorphisms (SNPs) in obese patients could contribute to the development of controlled antioxidant therapies potentially beneficial for the treatment of obesity-derived metabolic complications.
Full Text Available Abstract Background Down syndrome (DS neurons are more susceptible to oxidative stress and previous studies have shown that vitamin E was able to reduce oxidative stress and improve DS neurons' viability. Therefore, this study was done to investigate the protective role of γ-tocotrienol (γT3 in DS neurons from hydrogen peroxide (H2O2 -induced oxidative stress. The pro-apoptosis tendency of γT3 was compared to α-tocopherol (αT in non-stress condition as well. Methods Primary culture of DS and euploid neurons were divided into six groups of treatment: control, H2O2, γT3 pre-treatment with H2O2, γT3 only, αT pre-treatment with H2O2 and αT only. The treatments were assessed by MTS assay and apoptosis assay by single-stranded DNA (ssDNA apoptosis ELISA assay, Hoechst and Neu-N immunofluorescence staining. The cellular uptake of γT3 and αT was determined by HPLC while protein expressions were determined by Western blot. Comparison between groups was made by the Student's t test, one-way ANOVA and Bonferroni adjustment as well as two-way ANOVA for multiple comparisons. Results One day incubation of γT3 was able to reduced apoptosis of DS neurons by 10%, however γT3 was cytotoxic at longer incubation period (14 days and at concentrations ≥ 100 μM. Pre-treatment of αT and γT3 only attenuate apoptosis and increase cell viability in H2O2-treated DS and euploid neurons by 10% in which the effects were minimal to maintain most of the DS cells' morphology. γT3 act as a free radical scavenger by reducing ROS generated by H2O2. In untreated controls, DS neurons showed lower Bcl-2/Bax ratio and p53 expression compared to normal neurons, while cPKC and PKC-δ expressions were higher in DS neurons. On the other hand, pre-treatment of γT3 in H2O2-treated DS neurons have reduced Bcl-2/Bax ratio, which was not shown in euploid neurons. This suggests that pre-treatment of γT3 did not promote DS cell survival. Meanwhile γT3 and αT treatments
Andrea W.U. Busch
Full Text Available Tetrapyrroles are involved in light harvesting and light perception, electron-transfer reactions, and as co-factors for key enzymes and sensory proteins. Under conditions in which cells exhibit stress-induced imbalances of photosynthetic reactions, or light absorption exceeds the ability of the cell to use photoexcitation energy in synthesis reactions, redox imbalance can occur in photosynthetic cells. Such conditions can lead to the generation of reactive oxygen species (ROS associated with alterations in tetrapyrrole homeostasis. ROS accumulation can result in cellular damage and detrimental effects on organismal fitness, or ROS molecules can serve as signals to induce a protective or damage-mitigating oxidative stress signaling response in cells. Induced oxidative stress responses include tetrapyrrole-dependent and -independent mechanisms for mitigating ROS generation and/or accumulation. Thus, tetrapyrroles can be contributors to oxidative stress, but are also essential in the oxidative stress response to protect cells by contributing to detoxification of ROS. In this review, we highlight the interconnection and interdependence of tetrapyrrole metabolism with the occurrence of oxidative stress and protective oxidative stress signaling responses in photosynthetic organisms.
Cannizzo, Elvira S; Clement, Cristina C; Sahu, Ranjit; Follo, Carlo; Santambrogio, Laura
Immunosenescence is characterized by a decreased ability of the immune system to respond to foreign antigens, as well as a decreased ability to maintain tolerance to self-antigens. This results in an increased susceptibility to infection and cancer and reduced responses to vaccination [1-5]. The mechanisms underlying immunosenescence comprise a series of cellular and molecular events involving alteration of several biochemical pathways and different cellular populations, and for the most part our understanding of these molecular mechanisms is still fragmentary. In this review we will focus on the process of senescence associated with oxidative stress, in particular how protein oxidation alters the functionality of immune cells and how oxidative stress contributes to a chronic inflammatory process often referred as inflamm-aging. Copyright © 2011 Elsevier B.V. All rights reserved.
Full Text Available Anticholinesterase compounds, organophosphates (OPs and carbamates (CMs are commonly used for a variety of purposes in agriculture and in human and veterinary medicine. They exert their toxicity in mammalian system primarily by virtue of acetylcholinesterase (AChE inhibition at the synapses and neuromuscular junctions, leading into the signs of hypercholinergic preponderance. However, the mechanism(s involved in brain/muscle damage appear to be linked with alteration in antioxidant and the scavenging system leading to free radical-mediated injury. OPs and CMs cause excessive formation of F2-isoprostanes and F4-neuroprostanes, in vivo biomarkers of lipid peroxidation and generation of reactive oxygen species (ROS, and of citrulline, a marker of NO/NOS and reactive nitrogen species (RNS generation. In addition, during the course of these excitatory processes and inhibition of AChE, a high rate of ATP consumption, coupled with the inhibition of oxidative phosphorylation, compromise the cell's ability to maintain its energy levels and excessive amounts of ROS and RNS may be generated. Pretreatment with N-methyl D-aspartate (NMDA receptor antagonist memantine, in combination with atropine sulfate, provides significant protection against inhibition of AChE, increases of ROS/RNS, and depletion of high-energy phosphates induced by DFP/carbofuran. Similar antioxidative effects are observed with a spin trapping agent, phenyl-N-tert-butylnitrone (PBN or chain breaking antioxidant vitamin E. This review describes the mechanisms involved in anticholinesterase-induced oxidative/nitrosative injury in target organs of OPs/CMs, and protection by various agents.
Keil, Uta; Scherping, Isabel; Hauptmann, Susanne; Schuessel, Katin; Eckert, Anne; Müller, Walter E
Mitochondrial dysfunction including decrease of mitochondrial membrane potential and reduced ATP production represents a common final pathway of many conditions associated with oxidative stress, for example, hypoxia, hypoglycemia, and aging. Since the cognition-improving effects of the standard nootropic piracetam are usually more pronounced under such pathological conditions and young healthy animals usually benefit little by piracetam, the effect of piracetam on mitochondrial dysfunction following oxidative stress was investigated using PC12 cells and dissociated brain cells of animals treated with piracetam. Piracetam treatment at concentrations between 100 and 1000 μM improved mitochondrial membrane potential and ATP production of PC12 cells following oxidative stress induced by sodium nitroprusside (SNP) and serum deprivation. Under conditions of mild serum deprivation, piracetam (500 μM) induced a nearly complete recovery of mitochondrial membrane potential and ATP levels. Piracetam also reduced caspase 9 activity after SNP treatment. Piracetam treatment (100–500 mg kg−1 daily) of mice was also associated with improved mitochondrial function in dissociated brain cells. Significant improvement was mainly seen in aged animals and only less in young animals. Moreover, the same treatment reduced antioxidant enzyme activities (superoxide dismutase, glutathione peroxidase, and glutathione reductase) in aged mouse brain only, which are elevated as an adaptive response to the increased oxidative stress with aging. In conclusion, therapeutically relevant in vitro and in vivo concentrations of piracetam are able to improve mitochondrial dysfunction associated with oxidative stress and/or aging. Mitochondrial stabilization and protection might be an important mechanism to explain many of piracetam's beneficial effects in elderly patients. PMID:16284628
El Assar, Mariam; Angulo, Javier; Rodríguez-Mañas, Leocadio
Vascular aging, a determinant factor for cardiovascular disease and health status in the elderly, is now viewed as a modifiable risk factor. Impaired endothelial vasodilation is a early hallmark of arterial aging that precedes the clinical manifestations of vascular dysfunction, the first step to cardiovascular disease and influencing vascular outcomes in the elderly. Accordingly, the preservation of endothelial function is thought to be an essential determinant of healthy aging. With special attention on the effects of aging on the endothelial function, this review is focused on the two main mechanisms of aging-related endothelial dysfunction: oxidative stress and inflammation. Aging vasculature generates an excess of the reactive oxygen species (ROS), superoxide and hydrogen peroxide, that compromise the vasodilatory activity of nitric oxide (NO) and facilitate the formation of the deleterious radical, peroxynitrite. Main sources of ROS are mitochondrial respiratory chain and NADPH oxidases, although NOS uncoupling could also account for ROS generation. In addition, reduced antioxidant response mediated by erythroid-2-related factor-2 (Nrf2) and downregulation of mitochondrial manganese superoxide dismutase (SOD2) contributes to the establishment of chronic oxidative stress in aged vessels. This is accompanied by a chronic low-grade inflammatory phenotype that participates in defective endothelial vasodilation. The redox-sensitive transcription factor, nuclear factor-κB (NF-κB), is upregulated in vascular cells from old subjects and drives a proinflammatory shift that feedbacks oxidative stress. This chronic NF-κB activation is contributed by increased angiotensin-II signaling and downregulated sirtuins and precludes adequate cellular response to acute ROS generation. Interventions targeted to recover endogenous antioxidant capacity and cellular stress response rather than exogenous antioxidants could reverse oxidative stress-inflammation vicious cycle in
Syslová, Kamila; Böhmová, Adéla; Mikoška, Miloš; Kuzma, Marek; Pelclová, Daniela; Kačer, Petr
Aging is a complex process of organism decline in physiological functions. There is no clear theory explaining this phenomenon, but the most accepted one is the oxidative stress theory of aging. Biomarkers of oxidative stress, substances, which are formed during oxidative damage of phospholipids, proteins, and nucleic acids, are present in body fluids of diseased people as well as the healthy ones (in a physiological concentration). 8-iso prostaglandin F2α is the most prominent biomarker of phospholipid oxidative damage, o-tyrosine, 3-chlorotyrosine, and 3-nitrotyrosine are biomarkers of protein oxidative damage, and 8-hydroxy-2(')-deoxyguanosine and 8-hydroxyguanosine are biomarkers of oxidative damage of nucleic acids. It is thought that the concentration of biomarkers increases as the age of people increases. However, the concentration of biomarkers in body fluids is very low and, therefore, it is necessary to use a sensitive analytical method. A combination of HPLC and MS was chosen to determine biomarker concentration in three groups of healthy people of a different age (twenty, forty, and sixty years) in order to find a difference among the groups.
Yang, Yang; Durando, Michael; Smith-Roe, Stephanie L.; Sproul, Chris; Greenwalt, Alicia M.; Kaufmann, William; Oh, Sehyun; Hendrickson, Eric A.; Vaziri, Cyrus
The E3 ubiquitin ligase Rad18 mediates tolerance of replication fork-stalling bulky DNA lesions, but whether Rad18 mediates tolerance of bulky DNA lesions acquired outside S-phase is unclear. Using synchronized cultures of primary human cells, we defined cell cycle stage-specific contributions of Rad18 to genome maintenance in response to ultraviolet C (UVC) and H2O2-induced DNA damage. UVC and H2O2 treatments both induced Rad18-mediated proliferating cell nuclear antigen mono-ubiquitination during G0, G1 and S-phase. Rad18 was important for repressing H2O2-induced (but not ultraviolet-induced) double strand break (DSB) accumulation and ATM S1981 phosphorylation only during G1, indicating a specific role for Rad18 in processing of oxidative DNA lesions outside S-phase. However, H2O2-induced DSB formation in Rad18-depleted G1 cells was not associated with increased genotoxin sensitivity, indicating that back-up DSB repair mechanisms compensate for Rad18 deficiency. Indeed, in DNA LigIV-deficient cells Rad18-depletion conferred H2O2-sensitivity, demonstrating functional redundancy between Rad18 and non-homologous end joining for tolerance of oxidative DNA damage acquired during G1. In contrast with G1-synchronized cultures, S-phase cells were H2O2-sensitive following Rad18-depletion. We conclude that although Rad18 pathway activation by oxidative lesions is not restricted to S-phase, Rad18-mediated trans-lesion synthesis by Polη is dispensable for damage-tolerance in G1 (because of back-up non-homologous end joining-mediated DSB repair), yet Rad18 is necessary for damage tolerance during S-phase. PMID:23295675
Bagan, Jose; Saez, Guillermo; Tormos, Carmen; Gavalda, Carmen; Sanchis, Jose M; Bagan, Leticia; Scully, Crispian
This study analyzed the oxidative stress status in patients with recurrent aphthous stomatitis (RAS) in the presence and absence of active ulceration. Oxidative stress was analyzed in peripheral mononuclear cells of 28 RAS patients with active ulceration and 29 controls. A further blood sample was collected from nine subjects randomly selected from the 28 RAS cases, during the period in which the patients did not have active oral ulceration. The reduced glutathione (GSH), malondialdehyde (MDA), and oxidized glutathione (GSSG) levels were measured in these samples. The mean MDA and GSSG levels were significantly higher in patients with active RAS than in the controls, while GSH was lower in the RAS group (p < 0.01). There was a nonsignificant tendency toward higher MDA and GSSG levels in patients with major RAS compared with minor RAS. On comparing the serum findings in the nine RAS patients in the presence and absence of lesions, the presence of ulceration was associated with even higher MDA and GSSG levels and lower GSH concentrations (p < 0.05) CONCLUSIONS: Oxidative stress was detected in our RAS patients.
Ellegaard, Pernille Kempel; Poulsen, Henrik Enghusen
Oxidative stress to DNA from smoking was investigated in one randomized smoking cessation study and in 36 cohort studies from excretion of urinary 8-oxo-7-hydrodeoxyguanosine (8-oxodG). Meta-analysis of the 36 cohort studies showed smoking associated with a 15.7% (95% CL 11.0:20.3, p ....0001) increased oxidative stress to DNA, in agreement with the reduction of oxidative stress to DNA found in the smoking cessation study. Meta-analysis of the 22 studies that used chromatography methodology on 1709 persons showed a significant 29.3% increase in smokers (95% CL 17.3;41.3), but meta-analysis of 14...... studies on 3668 persons using ELISA methodology showed a non-significant effect of 8.7% [95% CL −1.2;18.6]. Tobacco smoke induces oxidative damage to DNA; however, this is not detected with ELISA methodology. Currently, the use of existing ELISA methodology to measure urinary excretion of 8-oxo-7...
Urquiaga, I; Leighton, F
In recent years there has been a remarkable increment in scientific articles dealing with oxidative stress. Several reasons justify this trend: knowledge about reactive oxygen and nitrogen species metabolism; definition of markers for oxidative damage; evidence linking chronic diseases and oxidative stress; identification of flavonoids and other dietary polyphenol antioxidants present in plant foods as bioactive molecules; and data supporting the idea that health benefits associated with fruits, vegetables and red wine in the diet are probably linked to the polyphenol antioxidants they contain. In this review we examine some of the evidence linking chronic diseases and oxidative stress, the distribution and basic structure of plant polyphenol antioxidants, some biological effects of polyphenols, and data related to their bioavailability and the metabolic changes they undergo in the intestinal lumen and after absorption into the organism. Finally, we consider some of the challenges that research in this area currently faces, with particular emphasis on the contributions made at the International Symposium "Biology and Pathology of Free Radicals: Plant and Wine Polyphenol Antioxidants" held July 29-30, 1999, at the Catholic University, Santiago, Chile and collected in this special issue of Biological Research.
Chen, Feng; Liu, Yingxia; Wong, Nai-Kei; Xiao, Jia; So, Kwok-Fai
Stem cell aging is a process in which stem cells progressively lose their ability to self-renew or differentiate, succumb to senescence or apoptosis, and eventually become functionally depleted. Unresolved oxidative stress and concomitant oxidative damages of cellular macromolecules including nucleic acids, proteins, lipids, and carbohydrates have been recognized to contribute to stem cell aging. Excessive production of reactive oxygen species and insufficient cellular antioxidant reserves compromise cell repair and metabolic homeostasis, which serves as a mechanistic switch for a variety of aging-related pathways. Understanding the molecular trigger, regulation, and outcomes of those signaling networks is critical for developing novel therapies for aging-related diseases by targeting stem cell aging. Here we explore the key features of stem cell aging biology, with an emphasis on the roles of oxidative stress in the aging process at the molecular level. As a concept of cytoprotection of stem cells in transplantation, we also discuss how systematic enhancement of endogenous antioxidant capacity before or during graft into tissues can potentially raise the efficacy of clinical therapy. Finally, future directions for elucidating the control of oxidative stress and developing preventive/curative strategies against stem cell aging are discussed.
Magalhães, José; Ferreira, Rita; Marques, Franklim; Olivera, Eduardo; Soares, José; Ascensão, António
Indoor climbing is a worldwide sport with particular physiological and physical demands. The purpose of this study was to analyze the effect of sustained indoor climbing until exhaustion on plasma oxidative stress markers, and to relate it to whole-body dynamic exercise performed at the same percentage of maximal oxygen uptake (VO2max). Fourteen male indoor climbers continuously climbed a competition-style route until exhaustion. Oxygen consumption and heart rate were continuously monitored during the climbing exercise. One week later, subjects performed a treadmill running protocol with the same duration and percentage of VO2max as that of climbing exercise. Blood samples were collected at rest, immediately after, and 1 h after both exercise protocols to analyze plasma levels of reduced (GSH) and oxidized (GSSG) glutathione, malondialdehyde (MDA), protein sulfhydryl (-SH) and carbonyl (CG) groups, total antioxidant status (TAS) and uric acid (UA), and total blood leukocytes, neutrophil, and lymphocyte counts. Compared with running, climbing significantly increased the %GSSG, MDA, CG, TAS, and UA and decreased the GSH and -SH content. Blood counts of total leukocytes and neutrophils increased immediately after and 1 h after both running and climbing (Pclimbing than in running (Pclimbing (Pindoor climbing induces plasma oxidative stress. Moreover, results suggest that an ischemia-reperfusion prooxidant-based mechanism related to climbers' sustained and intermittent isometric forearm muscle contractions might have significantly contributed to observed plasma oxidative stress.
Full Text Available In the recent years there has been considerable interest in mountain sports, including mountaineering, owing to the general availability of climbing clothing and equipment as well trainings and professional literature. This raised a new question for the environmental and mountain medicine: Is mountaineering harmful to health? Potential hazards include the conditions existing in the alpine environment, i.e. lower atmospheric pressure leading to the development of hypobaric hypoxia, extreme physical effort, increased UV radiation, lack of access to fresh food, and mental stress. A reasonable measure of harmfulness of these factors is to determine the increase in the level of oxidative stress. Alpine environment can stimulate the antioxidant enzyme system but under specific circumstances it may exceed its capabilities with simultaneous consumption of low-molecular antioxidants resulting in increased generation of reactive oxygen species (ROS. This situation is referred to as oxidative stress. Rapid and uncontrolled proliferation of reactive oxygen species leads to a number of adverse changes, resulting in the above-average damage to the lipid structures of cell membranes (peroxidation, proteins (denaturation, and nucleic acids. Such situation within the human body cannot take place without resultant systemic consequences. This explains the malaise of people returning from high altitude and a marked decrease in their physical fitness. In addition, a theory is put forward that the increase in the level of oxidative stress is one of the factors responsible for the onset of acute mountain sickness (AMS. However, such statement requires further investigation because the currently available literature is inconclusive. This article presents the causes and effects of development of oxidative stress in the high mountains.
Przybyszewski, Waldemar M; Rzeszowska-Wolny, Joanna
Aging, significant impairment of the oxidation/reduction balance, infection, and inflammation are recognized risk factors of benign hyperplasia and prostate cancer. Chronic symptomatic and asymptomatic prostate inflammatory processes generate significantly elevated levels of reactive oxygen and nitrogen species, and halogenated compounds. Prostate cancer patients showed significantly higher lipid peroxidation and lower antioxidant levels in peripheral blood than healthy controls, whereas patients with prostate hyperplasia did not show such symptoms. Oxidative/nitrosative/halogenative stress causes DNA modifications leading to genome instability that may initiate carcinogenesis; however, it was shown that oxidative damage alone is not sufficient to initiate this process. Peroxidation products induced by reactive oxygen and nitrogen species seem to take part in epigenetic mechanisms regulating genome activity. One of the most common changes occurring in more than 90% of all analyzed prostate cancers is the silencing of GSTP1 gene activity. The gene encodes glutathione transferase, an enzyme participating in detoxification processes. Prostate hyperplasia is often accompanied by chronic inflammation and such a relationship was not observed in prostate cancer. The participation of infection and inflammation in the development of hyperplasia is unquestionable and these factors probably also take part in initiating the early stages of prostate carcinogenesis. Thus it seems that therapeutic strategies that prevent genome oxidative damage in situations involving oxidative/nitrosative/halogenative stress, i.e. use of antioxidants, plant steroids, antibiotics, and non-steroidal anti-inflammatory drugs, could help prevent carcinogenesis.
Waldemar M. Przybyszewski
Full Text Available Aging, significant impairment of the oxidation/reduction balance, infection, and inflammation are recognized risk factors of benign hyperplasia and prostate cancer. Chronic symptomatic and asymptomatic prostate inflammatory processes generate significantly elevated levels of reactive oxygen and nitrogen species, and halogenated compounds. Prostate cancer patients showed significantly higher lipid peroxidation and lower antioxidant levels in peripheral blood than healthy controls, whereas patients with prostate hyperplasia did not show such symptoms. Oxidative/nitrosative/halogenative stress causes DNA modifications leading to genome instability that may initiate carcinogenesis; however, it was shown that oxidative damage alone is not sufficient to initiate this process. Peroxidation products induced by reactive oxygen and nitrogen species seem to take part in epigenetic mechanisms regulating genome activity. One of the most common changes occurring in more than 90�0of all analyzed prostate cancers is the silencing of GSTP1 gene activity. The gene encodes glutathione transferase, an enzyme participating in detoxification processes. Prostate hyperplasia is often accompanied by chronic inflammation and such a relationship was not observed in prostate cancer. The participation of infection and inflammation in the development of hyperplasia is unquestionable and these factors probably also take part in initiating the early stages of prostate carcinogenesis. Thus it seems that therapeutic strategies that prevent genome oxidative damage in situations involving oxidative/nitrosative/halogenative stress, i.e. use of antioxidants, plant steroids, antibiotics, and non-steroidal anti-inflammatory drugs, could help prevent carcinogenesis.
Background: Oxidative stress is known to play a role in the pathophysiology of metabolic syndrome and its components. Racial differences may exist in the level of markers of oxidative stress and antioxidants in patients with metabolic syndrome. Aim: The aim of this study was to determine the oxidative stress and ...
Liu, Shaobin; Zeng, Tingying Helen; Hofmann, Mario; Burcombe, Ehdi; Wei, Jun; Jiang, Rongrong; Kong, Jing; Chen, Yuan
Health and environmental impacts of graphene-based materials need to be thoroughly evaluated before their potential applications. Graphene has strong cytotoxicity toward bacteria. To better understand its antimicrobial mechanism, we compared the antibacterial activity of four types of graphene-based materials (graphite (Gt), graphite oxide (GtO), graphene oxide (GO), and reduced graphene oxide (rGO)) toward a bacterial model-Escherichia coli. Under similar concentration and incubation conditions, GO dispersion shows the highest antibacterial activity, sequentially followed by rGO, Gt, and GtO. Scanning electron microscope (SEM) and dynamic light scattering analyses show that GO aggregates have the smallest average size among the four types of materials. SEM images display that the direct contacts with graphene nanosheets disrupt cell membrane. No superoxide anion (O(2)(•-)) induced reactive oxygen species (ROS) production is detected. However, the four types of materials can oxidize glutathione, which serves as redox state mediator in bacteria. Conductive rGO and Gt have higher oxidation capacities than insulating GO and GtO. Results suggest that antimicrobial actions are contributed by both membrane and oxidation stress. We propose that a three-step antimicrobial mechanism, previously used for carbon nanotubes, is applicable to graphene-based materials. It includes initial cell deposition on graphene-based materials, membrane stress caused by direct contact with sharp nanosheets, and the ensuing superoxide anion-independent oxidation. We envision that physicochemical properties of graphene-based materials, such as density of functional groups, size, and conductivity, can be precisely tailored to either reducing their health and environmental risks or increasing their application potentials. © 2011 American Chemical Society
The field of oxidative stress research embraces chemistry, biochemistry, cell biology, physiology and pathophysiology, all the way to medicine and health and disease research. “Oxidative stress is an imbalance between oxidants and antioxidants in favor of the oxidants, leading to a disruption of redox signaling and control ...
Tagil, Suleyman Murat; Celik, Huseyin Tugrul; Ciftci, Sefa; Kazanci, Fatmanur Hacievliyagil; Arslan, Muzeyyen; Erdamar, Nazan; Kesik, Yunus; Erdamar, Husamettin; Dane, Senol
Wet-cupping therapy is one of the oldest known medical techniques. Although it is widely used in various conditions such as acute\\chronic inflammation, infectious diseases, and immune system disorders, its mechanism of action is not fully known. In this study, we investigated the oxidative status as the first step to elucidate possible mechanisms of action of wet cupping. Wet cupping therapy is implemented to 31 healthy volunteers. Venous blood samples and Wet cupping blood samples were taken concurrently. Serum nitricoxide, malondialdehyde levels and activity of superoxide dismutase and myeloperoxidase were measured spectrophotometrically. Wet cupping blood had higher activity of myeloperoxidase, lower activity of superoxide dismutase, higher levels of malondialdehyde and nitricoxide compared to the venous blood. Wet cupping removes oxidants and decreases oxidative stress. Copyright © 2014 Elsevier Ltd. All rights reserved.
Friederich, Malou; Hansell, Peter; Palm, Fredrik
The role of altered mitochondria function has recently emerged as an important mechanism for the development of diabetic complications. Altered mitochondria function has also been implicated in the ageing process, defective insulin secretion, hypertension, arteriosclerosis, ischemia-reperfusion injury and apoptosis. Normally, the mitochondria are associated with ATP production using primarily pyruvate as the substrate, but recent reports indicate that tissue specific preferences exist. Also, the mitochondria are a substantial source of superoxide production, preferentially during states of elevated intracellular glucose concentrations. The mitochondria function is regulated by several factors including nitric oxide, oxidative stress, mammalian target of rapamycin, ADP and P(i) availability, which result in a complex regulation of ATP production and oxygen consumption, but also superoxide generation. These factors seem to be tissue specific, which warrants a more diverse mechanistic model applying to that specific tissue or cell type. This review presents the basic functions of the mitochondria and focuses on the complex interplay between oxidative stress, nitric oxide and uncoupling proteins in regulating mitochondria function with special focus on diabetes-induced alterations occurring on the mitochondria level.
Lerdweeraphon, Wichaporn; Wyss, James Michael; Boonmars, Thidarut; Roysommuti, Sanya
Perinatal exposure to taurine (a β-amino acid) can alter adult physiological functions, including arterial pressure, hormonal and renal functions. Whereas perinatal taurine supplementation appears to have only minor effects on adult physiology, perinatal taurine depletion is associated with multiple adverse health effects, especially in animals postnatally exposed to other insults. New studies indicate that the mechanism for many of the physiological effects of taurine is related to the antioxidant activity of taurine. Thus the perinatal taurine depletion leads to oxidative stress in adult animals. It is likely that perinatal taurine depletion increases oxidative stress throughout life and that the early life taurine depletion leads to perinatal, epigenetic programming that impacts adult physiological function.
Full Text Available Parkinson disease is a chronic, progressive neurological disease that is associated with a loss of dopaminergic neurons in the substantia nigra of the brain. The molecular mechanisms underlying the loss of these neurons still remain elusive. Oxidative stress is thought to play an important role in dopaminergic neurotoxicity. Complex I deficiencies of the respiratory chain account for the majority of unfavorable neuronal degeneration in Parkinson’s Disease. Environmental factors, such as neurotoxins, insecticides like rotenone, pesticides like Paraquat, dopamine itself and genetic mutations in Parkinson’s Disease related proteins contribute to mitochondrial dysfunction which precedes reactive oxygen species formation. In this mini review, we give an update of the classical pathways involving these mechanisms of neurodegeneration, the biochemical and molecular events that mediate or regulate DA neuronal vulnerability, and the role of PD-related gene products in modulating cellular responses to oxidative stress in the course of the neurodegenerative process.
Can, Murat; Guven, Berrak; Bektas, Sibel; Arikan, Ilker
We aimed to determine the oxidative stress and antioxidant status in preeclamptic placenta. Also, we investigated the apoptotic index of villous trophoblast and proliferation index of cytotrophoblasts. The study included 32 pregnant with preeclampsia and 31 normotensive healthy pregnant women. Malondialdehyde (MDA) and total antioxidant status (TAS) levels were measured in the placenta. For detection of apoptosis and proliferation in trophoblast, apoptosis protease activating factor 1 (APAF-1) and Ki-67 were used. Placental MDA levels in preeclamptic women were significantly higher than normal pregnancies (p=0.002). There was no significant difference between the groups in the TAS levels of placenta (p=0.773). Also, the apoptotic index in villous trophoblasts increased (ppreeclampsia (p=0.850). Increased oxidative stress and apoptosis in pathological placenta are not balanced by antioxidant systems and proliferation mechanisms. Copyright © 2014 Elsevier Ltd. All rights reserved.
Robert J Aitken
Full Text Available One of the major causes of defective sperm function is oxidative stress, which not only disrupts the integrity of sperm DNA but also limits the fertilizing potential of these cells as a result of collateral damage to proteins and lipids in the sperm plasma membrane. The origins of such oxidative stress appear to involve the sperm mitochondria, which have a tendency to generate high levels of superoxide anion as a prelude to entering the intrinsic apoptotic cascade. Unfortunately, these cells have very little capacity to respond to such an attack because they only possess the first enzyme in the base excision repair (BER pathway, 8-oxoguanine glycosylase 1 (OGG1. The latter successfully creates an abasic site, but the spermatozoa cannot process the oxidative lesion further because they lack the downstream proteins (APE1, XRCC1 needed to complete the repair process. It is the responsibility of the oocyte to continue the BER pathway prior to initiation of S-phase of the first mitotic division. If a mistake is made by the oocyte at this stage of development, a mutation will be created that will be represented in every cell in the body. Such mechanisms may explain the increase in childhood cancers and other diseases observed in the offspring of males who have suffered oxidative stress in their germ line as a consequence of age, environmental or lifestyle factors. The high prevalence of oxidative DNA damage in the spermatozoa of male infertility patients may have implications for the health of children conceivedin vitro and serves as a driver for current research into the origins of free radical generation in the germ line.
Signorini, Cinzia; Leoncini, Silvia; Gardi, Concetta; Ciccoli, Lucia; Giardini, Anna; Vecchio, Daniela; Arezzini, Beatrice
After a general introduction, the main pathways of ethanol metabolism (alcohol dehydrogenase, catalase, coupling of catalase with NADPH oxidase and microsomal ethanol-oxidizing system) are shortly reviewed. The cytochrome P450 isoform (CYP2E1) specifically involved in ethanol oxidation is discussed. The acetaldehyde metabolism and the shift of the NAD/NADH ratio in the cellular environment (reductive stress) are stressed. The toxic effects of acetaldehyde are mentioned. The ethanol-induced oxidative stress: the increased MDA formation by incubated liver preparations, the absorption of conjugated dienes in mitochondrial and microsomal lipids and the decrease in the most unsaturated fatty acids in liver cell membranes are discussed. The formation of carbon-centered (1-hydroxyethyl) and oxygen-centered (hydroxyl) radicals during the metabolism of ethanol is considered: the generation of hydroxyethyl radicals, which occurs likely during the process of univalent reduction of dioxygen, is highlighted and is carried out by ferric cytochrome P450 oxy-complex (P450–Fe3+O2·−) formed during the reduction of heme-oxygen. The ethanol-induced lipid peroxidation has been evaluated, and it has been shown that plasma F2-isoprostanes are increased in ethanol toxicity. PMID:20606811
Butkowski, Eugene G; Jelinek, Herbert F
The increasing prevalence of hyperglycaemia implicates a state of oxidative stress and inflammation. Traditional and emerging biomarkers associated with increasing hyperglycaemia were assessed to clarify their role they play in hyperglycaemia. 309 participants attending a rural diabetic screening program were categorised into control and quintile groups based upon glucose levels: 1st quintile - 6.1 mmol/L. Significant results were obtained for anthropometric data and biochemical markers - glucose, HbA1c and total cholesterol (P < 0.001); oxidative stress: glutathione (P < 0.001), glutathione:glutathione disulfide and 8-hydroxy-2-deoxyguanosine (P < 0.05). Interleukin -1β and inflammatory marker ratios IL-6/IL-10, IL-1β/IL-10, MCP-1/IL-10, IGF-1/IL-10 and IL-6/IL-1β were significant (P < 0.05). This study provided further evidence that inflammatory and oxidative stress biomarkers may contribute to diagnostic information associated with preclinical increases in BGL. Further we have provided a unique study in the analysis of ratios of inflammatory biomarkers and correlations with increasing BGL.
Srivastava, Ragni; Lohokare, Rajeev; Prasad, Rajniti
Bacterial meningitis is a common cause of morbidity and mortality in children. The oxidative stress in bacterial meningitis is barely determined. Forty children with bacterial meningitis were studied for their oxidants and antioxidants status in serum and cerebrospinal fluid. Fever (95%) was commonest presentation followed by seizure and vomiting. Neck rigidity and Kernig's sign were present in 37.5% and 27.5% cases, respectively. Plasma and cerebrospinal fluid malondialdehyde, protein carbonyl and nitrite levels were significantly raised in cases (p ascorbic acid, glutathione and superoxide dismutase levels were significantly decreased in children with septic meningitis (p ascorbic acid and superoxide dismutase indicates utilization of the antioxidants in septic meningitis. Thus, changes in oxidants and antioxidants observed suggest production of reactive oxygen species and their possible role in pathogenesis of septic meningitis.
Narsaria, Nidhi; Mohanty, C; Das, B K; Mishra, S P; Prasad, Rajniti
Fifty cases of severe malaria were studied for their oxidant and antioxidant status. Severe anemia (54%) was the most common presentation followed by hyperpyrexia, cerebral malaria and jaundice. Plasma malondialdehyde, protein carbonyl, nitrite, ascorbic acid and copper levels were significantly raised in cases as compared with controls (p children with severe malaria (p < 0.001). Plasma zinc was increased in cases but difference is not statistically significant. Significantly decreased level of nitrites and increased value of glutathione was found in patients with hemoglobinuria and jaundice, respectively. The significantly elevated malondialdehyde and protein carbonyl levels reflect the increased oxidative stress, whereas decreased levels of glutathione and superoxide dismutase point toward utilization of the antioxidants in severe malaria. Thus, changes in oxidants and antioxidants observed suggest the production of reactive oxygen species and their possible role in pathogenesis of severe malaria.
Full Text Available Both iron deficiency and hyperglycemia are highly prevalent globally for pregnant women. Iron supplementation is recommended during pregnancy to control iron deficiency. The purposes of the review are to assess the oxidative effects of iron supplementation and the potential relationship between iron nutrition and gestational diabetes. High doses of iron (~relative to 60 mg or more daily for adult humans can induce lipid peroxidation in vitro and in animal studies. Pharmaceutical doses of iron supplements (e.g., 10× RDA or more for oral supplements or direct iron supplementation via injection or addition to the cell culture medium for a short or long duration will induce DNA damage. Higher heme-iron intake or iron status measured by various biomarkers, especially serum ferritin, might contribute to greater risk of gestational diabetes, which may be mediated by iron oxidative stress though lipid oxidation and/or DNA damage. However, information is lacking about the effect of low dose iron supplementation (≤60 mg daily on lipid peroxidation, DNA damage and gestational diabetes. Randomized trials of low-dose iron supplementation (≤60 mg daily for pregnant women are warranted to test the relationship between iron oxidative stress and insulin resistance/gestational diabetes, especially for iron-replete women.
Wu, Qi; Su, Nana; Zhang, Xiaoyan; Liu, Yuanyuan; Cui, Jin; Liang, Yongchao
The cross talk among hydrogen peroxide (H2O2), nitric oxide (NO) and UV RESISTANCE LOCUS8 (UVR8) in UV-B-induced anthocyanin accumulation in the hypocotyls of radish sprouts was investigated. The results showed that UV-B irradiation significantly increased the anthocyanin accumulation and the expression of UVR8, and a similar trend appeared in radish sprouts subjected to cadmium, chilling and salt stresses regardless of light source. However, these responses disappeared under dark exposure. These results suggest that abiotic stress-induced anthocyanin accumulation and UVR8 expression were light-dependent. Moreover, abiotic stresses all enhanced the production of H2O2 and exogenous H2O2 addition significantly increased the anthocyanin concentration and UVR8 transcription, while these increases were severely inhibited by addition of dimethylthiourea (DMTU, a chemical trap for H2O2). It seems to suggest that H2O2 played an important role in the anthocyanin biosynthesis. Furthermore, addition of 0.5 mM sodium nitroprusside (SNP, a NO-releasing compound) substantially induced the anthocyanin accumulation, and H2O2-induced anthocyanin accumulation and UVR8 expression were significantly suppressed by co-treatment with 2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl (PTIO, a NO scavenger), which was parallel with the expression of anthocyanin biosynthesis-related transcription factors and structural genes. All these results demonstrate that both H2O2 and NO are involved in UV-B-induced anthocyanin accumulation, and there is a crosstalk between them as well as a classical UVR8 pathway.
Takaki, Akinobu; Yamamoto, Kazuhide
Oxidative stress is becoming recognized as a key factor in the progression of chronic liver disease (CLD) and hepatocarcinogenesis. The metabolically important liver is a major reservoir of mitochondria that serve as sources of reactive oxygen species, which are apparently responsible for the initiation of necroinflammation. As a result, CLD could be a major inducer of oxidative stress. Chronic hepatitis C is a powerful generator of oxidative stress, causing a high rate of hepatocarcinogenesis among patients with cirrhosis. Non-alcoholic steatohepatitis is also associated with oxidative stress although its hepatocarcinogenic potential is lower than that of chronic hepatitis C. Analyses of serum markers and histological findings have shown that hepatocellular carcinoma correlates with oxidative stress and experimental data indicate that oxidative stress increases the likelihood of developing hepatocarcinogenesis. However, the results of antioxidant therapy have not been favorable. Physiological oxidative stress is a necessary biological response, and thus adequate control of oxidative stress and a balance between oxidative and anti-oxidative responses is important. Several agents including metformin and L-carnitine can reportedly control mechanistic oxidative stress. This study reviews the importance of oxidative stress in hepatocarcinogenesis and of control strategies for the optimal survival of patients with CLD and hepatocellular carcinoma.
Salmon, Adam B; Richardson, Arlan; Pérez, Viviana I
The oxidative stress theory of aging predicts that manipulations that alter oxidative stress/damage will alter aging. The gold standard for determining whether aging is altered is life span, i.e., does altering oxidative stress/damage change life span? Mice with genetic manipulations in their antioxidant defense system designed to directly address this prediction have, with few exceptions, shown no change in life span. However, when these transgenic/knockout mice are tested using models that develop various types of age-related pathology, they show alterations in progression and/or severity of pathology as predicted by the oxidative stress theory: increased oxidative stress accelerates pathology and reduced oxidative stress retards pathology. These contradictory observations might mean that (a) oxidative stress plays a very limited, if any, role in aging but a major role in health span and/or (b) the role that oxidative stress plays in aging depends on environment. In environments with minimal stress, as expected under optimal husbandry, oxidative damage plays little role in aging. However, under chronic stress, including pathological phenotypes that diminish optimal health, oxidative stress/damage plays a major role in aging. Under these conditions, enhanced antioxidant defenses exert an "antiaging" action, leading to changes in life span, age-related pathology, and physiological function as predicted by the oxidative stress theory of aging. (c) 2009 Elsevier Inc. All rights reserved.
Fuentes, Eduardo; Palomo, Iván
Thrombotic events are common causes of morbidity and mortality in the elderly. Age-accelerated vascular injury is commonly considered to result from increased oxidative stress. There is abundant evidence that oxidative stress regulate several components of thrombotic processes, including platelet activation. Thus oxidative stress can trigger platelet hyperreactivity by decreasing nitric oxide bioavailability. Therefore oxidative stress measurement may help in the early identification of asymptomatic subjects at risk of thrombosis. In addition, oxidative stress inhibitors and platelet-derived nitric oxide may represent a novel anti-aggregation/-activation approach. In this article the relative contribution of oxidative stress and platelet activation in aging is explored. Copyright © 2016 Elsevier Inc. All rights reserved.
Sharma Rakesh K
Full Text Available Abstract In a healthy body, ROS (reactive oxygen species and antioxidants remain in balance. When the balance is disrupted towards an overabundance of ROS, oxidative stress (OS occurs. OS influences the entire reproductive lifespan of a woman and even thereafter (i.e. menopause. OS results from an imbalance between prooxidants (free radical species and the body's scavenging ability (antioxidants. ROS are a double-edged sword – they serve as key signal molecules in physiological processes but also have a role in pathological processes involving the female reproductive tract. ROS affect multiple physiological processes from oocyte maturation to fertilization, embryo development and pregnancy. It has been suggested that OS modulates the age-related decline in fertility. It plays a role during pregnancy and normal parturition and in initiation of preterm labor. Most ovarian cancers appear in the surface epithelium, and repetitive ovulation has been thought to be a causative factor. Ovulation-induced oxidative base damage and damage to DNA of the ovarian epithelium can be prevented by antioxidants. There is growing literature on the effects of OS in female reproduction with involvement in the pathophsiology of preeclampsia, hydatidiform mole, free radical-induced birth defects and other situations such as abortions. Numerous studies have shown that OS plays a role in the pathoysiology of infertility and assisted fertility. There is some evidence of its role in endometriosis, tubal and peritoneal factor infertility and unexplained infertility. This article reviews the role OS plays in normal cycling ovaries, follicular development and cyclical endometrial changes. It also discusses OS-related female infertility and how it influences the outcomes of assisted reproductive techniques. The review comprehensively explores the literature for evidence of the role of oxidative stress in conditions such as abortions, preeclampsia, hydatidiform mole, fetal
Ding, Xiao; Yu, Lei; Ge, Chongyang; Ma, Haitian
Dehydroepiandrosterone (DHEA) is widely used as a nutritional supplement due to its putative anti-aging properties. However, the effect of DHEA in Leydig cells, a major target cell of DHEA biotransformation in male, are not clear. The present study aimed to investigate the preventative effect of DHEA on oxidative damage and apoptosis after H2O2 treatment in Leydig cells. The results showed that DHEA treatment attenuated the reduction of cell viability induced by H2O2. No differences were observed on the superoxide anion (O2-) content, while DHEA treatment decreased reactive oxygen species (ROS) and hydroxyl radical (•OH) content in H2O2-treated Leydig cells. Pre-treatment with DHEA increased peroxidase (POD) activity and decreased glutathione peroxidase (GSH-Px) activity in H2O2-treated Leydig cell. DHEA treatment attenuated DNA damage as indicated by the decreasing of tail moment, comet length and olive tail moment. Total apoptosis ratio and early apoptosis ratio were significantly decreased in H2O2-treated Leydig cell that were pre-treatment with DHEA. DHEA treatment decreased Bax, capase-9 and capase-3 mRNA levels in H2O2-treated Leydig cells. Our results demonstrated that pre-treatment with DHEA prevented the Leydig cells oxidative damage caused by H2O2 through increasing POD activity, which resulted in inhibition of •OH generation. Meanwhile, pre-treatment with DHEA inhibited H2O2-induced Leydig cells early apoptosis which mainly by reducing the pro-apoptotic protein Bax and caspases-9, caspases-3 mRNA levels. This information is important to understand the molecular mechanism of anti-ageing effect and potential application in treatment of oxidative stress induced related diseases of DHEA.
Stephens, Jeffrey Wayne
Increased oxidative stress has been implicated in the pathogenesis of atherosclerosis and coronary heart disease, and is a key feature of diabetes mellitus. Increased oxidative stress has numerous adverse effects on the vascular system, including the altered expression of cell adhesion molecules, induction of pro-inflammatory mediators and more specifically the oxidation of low density lipoprotein (LDL) to form oxidised LDL (Ox-LDL). As well as measuring the total degree of oxidative stress i...
Full Text Available Smog is created through the interactions between pollutants in the air, fog, and sunlight. Air pollutants, such as carbon monoxide, heavy metals, nitrogen oxides, ozone, sulfur dioxide, volatile organic vapors, and particulate matters, can induce oxidative stress in human directly or indirectly through the formation of reactive oxygen species. The outermost boundary of human skin and mucous layers are covered by a complex network of human-associated microbes. The relation between these microbial communities and their human host are mostly mutualistic. These microbes not only provide nutrients, vitamins, and protection against other pathogens, they also influence human's physical, immunological, nutritional, and mental developments. Elements in smog can induce oxidative stress to these microbes, leading to community collapse. Disruption of these mutualistic microbiota may introduce unexpected health risks, especially among the newborns and young children. Besides reducing the burning of fossil fuels as the ultimate solution of smog formation, advanced methods by using various physical, chemical, and biological means to reduce sulfur and nitrogen contains in fossil fuels could lower smog formation. Additionally, information on microbiota disruption, based on functional genomics, culturomics, and general ecological principles, should be included in the risk assessment of prolonged smog exposure to the health of human populations.
Full Text Available Endothelial dysfunction (ED is an early event in atherosclerotic disease, preceding clinical manifestations and complications. Increased reactive oxygen species (ROS have been implicated as important mechanisms that contribute to ED, and ROS’s may function as intracellular messengers that modulate signaling pathways. Several intracellular signal events stimulated by ROS have been defined, including the identification of two members of the mitogen activated protein kinase family (ERK1/2 and big MAP kinase, BMK1, tyrosine kinases (Src and Syk and different isoenzymes of PKC as redox-sensitive kinases. ROS regulation of signal transduction components include the modification in the activity of transcriptional factors such as NFkB and others that result in changes in gene expression and modifications in cellular responses. In order to understand the intracellular mechanisms induced by ROS in endothelial cells (EC, we are studying the response of human umbilical cord vein endothelial cells to increased ROS generation by different pro-atherogenic stimuli. Our results show that Homocysteine (Hcy and oxidized LDL (oxLDL enhance the activity and expression of oxidative stress markers, such as NFkB and heme oxygenase 1. These results suggest that these pro-atherogenic stimuli increase oxidative stress in EC, and thus explain the loss of endothelial function associated with the atherogenic process
Cervini-Silva, Javiera; Nieto-Camacho, Antonio; Gómez-Vidales, Virginia
Fibrous clays (sepiolite, palygorskite) are produced at 1.2m tonnes per year and have a wide range of industrial applications needing to replace long-fibre length asbestos. However, information on the beneficial effects of fibrous clays on health remains scarce. This paper reports on the effect of sepiolite (Vallecas, Spain) and palygorskite (Torrejón El Rubio, Spain) on cell damage via oxidative stress (determined as the progress of lipid peroxidation, LP). The extent of LP was assessed using the Thiobarbituric Acid Reactive Substances assay. The oxidant activity by fibrous clays was quantified using Electron-Paramagnetic Resonance. Sepiolite and palygorskite inhibited LP, whereby corresponding IC50 values were 6557±1024 and 4250±289μgmL(-1). As evidenced by dose-response experiments LP inhibition by palygorskite was surface-controlled. Fibrous clay surfaces did not stabilize HO species, except for suspensions containing 5000μgmL(-1). A strong oxidant (or weak anti-oxidant) activity favours the inhibition of LP by fibrous clays. Copyright © 2015 Elsevier B.V. All rights reserved.
Salech, Felipe; Ponce, Daniela P; SanMartín, Carol D; Rogers, Nicole K; Chacón, Carlos; Henríquez, Mauricio; Behrens, Maria I
Mild cognitive impairment (MCI) is a clinically detectable initial stage of cognitive deterioration with a high conversion rate to dementia. There is increasing evidence that some of the cerebral alterations present in Alzheimer type dementia can be found in peripheral tissues. We have previously shown that lymphocytes from Alzheimer's disease (AD) patients have increased susceptibility to hydrogen peroxide (H2O2)-induced death that depends on dementia severity. We here investigated whether lymphocytes from MCI patients show increased vulnerability to death, and explored the involvement of Poly [ADP-ribose] polymerase (PARP-1) and p53 in the regulation of this process. Lymphocytes from 16 MCI and 10 AD patients, and 15 healthy controls (HCs) were submitted to increasing concentrations of H2O2 for 20 h. Cell death was determined by flow cytometry, in the presence or absence of PARP-1 inhibitors (3-aminobenzamide (3-ABA) or Nicotinamide (NAM)), or the p53 inhibitor (nutlin-3) or stabilizer (pifithrin-α). PARP-1 and p53 mRNA levels were determined by quantitative PCR (qPCR). Lymphocytes from MCI patients showed increased susceptibility to death, attaining intermediate values between AD and controls. PARP inhibitors -3-ABA and NAM- markedly protected from H2O2-induced death, making the difference between MCI and controls disappear, but not the difference between AD and controls. PARP-1 mRNA expression was increased in MCI lymphocytes. Modulation of p53 with Nutlin-3 or pifithrin-α did not modify the H2O2-induced death of lymphocytes from MCI or AD patients, but augmented the death in control lymphocytes attaining levels similar to MCI and AD. Accordingly, p53 mRNA expression was increased in AD and MCI lymphocytes compared to controls. In all, these results show that increased oxidative death is present in lymphocytes at the MCI stage. PARP-1 has a preponderant role, with complete death protection achieved with PARP inhibition in MCI lymphocytes, but not in AD
Liu, Li; Wu, Wei; Li, Jing; Jiao, Wei-Hua; Liu, Li-Yun; Tang, Jie; Liu, Lei; Sun, Fan; Han, Bing-Nan; Lin, Hou-Wen
To investigate the cytoprotective effects of two sesquiterpene aminoquinones isolated from the marine sponge Dysidea fragilis, Dysidaminone H (DA8) and 3'-methylamino-avarone (DA14), we examined their effects against hydrogen peroxide (H 2 O 2 )-induced oxidative injury in human keratinocyte cell line and elucidated the underlying mechanisms. Cell viability was detected using a CCK-8 assay kit. Intracellular reactive oxygen species (ROS) production was measured by fluorescence of 2, 7-Dichlorodi-hydrofluorescein diacetate (DCFH-DA). Messenger RNA and protein expression were measured by real-time quantitative PCR and western blotting analysis. Immunocytochemistry was performed to determine the intracellular location of nuclear factorerythroid 2 p45 related factor 2 (Nrf2). The antioxidant response element (ARE)-luciferase reporter gene assay and RNA interference were used to establish the role of ARE and Nrf2. DA8 and DA14 (DAs) resisted H 2 O 2 induced decline of cell viability by inhibiting the accumulation of ROS. Meanwhile, DAs increased HO-1 expression and ARE activity and induced Nrf2 expression, as well as the accumulation of Nrf2 in the cell nucleus. However, silencing of Nrf2 abolished DAs-induced HO-1 expression and ARE luciferase activation. In addition, DAs induced the phosphorylation of both cyclic AMP-activated protein kinase-α (AMPKα) and extracellular signal-regulated kinase (ERK), while specific inhibitors of AMPKα and ERK abrogated HO1 upregulation and Nrf2 activation. DAs provided cytoprotective effects against H 2 O 2 -induced cytotoxicity by activation of the Nrf2/ARE/HO-1 pathway via phosphorylation of AMPKα and ERK. The findings suggested that DA8 and DA14 might be the candidate therapeutic agents for skin diseases caused by oxidative injury. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
Mouthuy, Pierre-Alexis; Snelling, Sarah J B; Dakin, Stephanie G; Milković, Lidija; Gašparović, Ana Čipak; Carr, Andrew J; Žarković, Neven
Oxidative stress occurs when the production of oxidants surpasses the antioxidant capacity in living cells. Oxidative stress is implicated in a number of pathological conditions such as cardiovascular and neurodegenerative diseases but it also has crucial roles in the regulation of cellular activities. Over the last few decades, many studies have identified significant connections between oxidative stress, inflammation and healing. In particular, increasing evidence indicates that the production of oxidants and the cellular response to oxidative stress are intricately connected to the fate of implanted biomaterials. This review article provides an overview of the major mechanisms underlying the link between oxidative stress and the biocompatibility of biomaterials. ROS, RNS and lipid peroxidation products act as chemo-attractants, signalling molecules and agents of degradation during the inflammation and healing phases. As chemo-attractants and signalling molecules, they contribute to the recruitment and activation of inflammatory and healing cells, which in turn produce more oxidants. As agents of degradation, they contribute to the maturation of the extracellular matrix at the healing site and to the degradation of the implanted material. Oxidative stress is itself influenced by the material properties, such as by their composition, their surface properties and their degradation products. Because both cells and materials produce and react with oxidants, oxidative stress may be the most direct route mediating the communication between cells and materials. Improved understanding of the oxidative stress mechanisms following biomaterial implantation may therefore help the development of new biomaterials with enhanced biocompatibility. Copyright © 2016 Elsevier Ltd. All rights reserved.
Conclusions: Primitive BM-EPCs showed vasculogenic dysfunction in early diabetes. However the oxidative stress is not denoted as the major initiating factor of its cause. Our results suggest that primitive BM-KSL cell has the ability to compensate oxidative stress levels in early diabetes by increasing the expression of anti-oxidative enzymes.
Torres, M D; Canal, J R; Pérez, C
Parameters related to oxidative stress were studied in a group of 10 Wistar diabetic rats and 10 control rats. The levels of total erythrocyte catalase activity in the diabetic animals were significantly (pC18:2) ratios. Greater vitaminE/triglyceride (TG) ratio, however, appeared in the control group. The corresponding vitamin A ratios (vitaminA/TG, vitaminA/PUFA, vitaminA/C 18:2) were higher in the control group. Our work corroborates the findings that fatty acid metabolism presents alterations in the diabetes syndrome and that the antioxidant status is affected.
The unicellular green algae Dunaliella salina contains various antioxidants which protect the cell from oxidative damage due to environmental stresses such as heavy metal stress. In the present study, the response of D. salina at the stationary growth phase to oxidative stress generated by cadmium chloride was ...
The WHO classification of endocrine tumors defines pheochromocytoma as a tumor arising from chromaffin cells in the adrenal medulla — an intra-adrenal paraganglioma. Closely related tumors of extra-adrenal sympathetic and parasympathetic paraganglia are classified as extra-adrenal paragangliomas. Almost all pheochromocytomas and paragangliomas produce catecholamines. The concentrations of catecholamines in pheochromocytoma tissues are enormous, potentially creating a volcano that can erupt at any time. Significant eruptions result in catecholamine storms called “attacks” or “spells”. Acute catecholamine crisis can strike unexpectedly, leaving traumatic memories of acute medical disaster that champions any intensive care unit. A very well-defined genotype-biochemical phenotype relationship exists, guiding proper and cost-effective genetic testing of patients with these tumors. Currently, the production of norepinephrine and epinephrine is optimally assessed by the measurement of their O-methylated metabolites, normetanephrine or metanephrine, respectively. Dopamine is a minor component, but some paragangliomas produce only this catecholamine or this together with norepinephrine. Methoxytyramine, the O-methylated metabolite of dopamine, is the best biochemical marker of these tumors. In those patients with equivocal biochemical results, a modified clonidine suppression test coupled with the measurement of plasma normetanephrine has recently been introduced. In addition to differences in catecholamine enzyme expression, the presence of either constitutive or regulated secretory pathways contributes further to the very unique mutation-dependent catecholamine production and release, resulting in various clinical presentations. Oxidative stress results from a significant imbalance between levels of prooxidants, generated during oxidative phosphorylation, and antioxidants. The gradual accumulation of prooxidants due to metabolic oxidative stress results in proto
Sergey N. Kochetkov
Full Text Available Hepatitis C virus (HCV is the etiological agent accounting for chronic liver disease in approximately 2–3% of the population worldwide. HCV infection often leads to liver fibrosis and cirrhosis, various metabolic alterations including steatosis, insulin and interferon resistance or iron overload, and development of hepatocellular carcinoma or non-Hodgkin lymphoma. Multiple molecular mechanisms that trigger the emergence and development of each of these pathogenic processes have been identified so far. One of these involves marked induction of a reactive oxygen species (ROS in infected cells leading to oxidative stress. To date, markers of oxidative stress were observed both in chronic hepatitis C patients and in various in vitro systems, including replicons or stable cell lines expressing viral proteins. The search for ROS sources in HCV-infected cells revealed several mechanisms of ROS production and thus a number of cellular proteins have become targets for future studies. Furthermore, during last several years it has been shown that HCV modifies antioxidant defense mechanisms. The aim of this review is to summarize the present state of art in the field and to try to predict directions for future studies.
Full Text Available Melamine is a nitrogen heterocyclic triazine compound which is widely used as an industrial chemical. Although melamine is not considered to be acutely toxic with a high LD50 in animals, food contaminated with melamine expose risks to the human health. Melamine has been reported to be responsible for the renal impairment in mammals, its toxicity on the reproductive system, however, has not been adequately assessed. In the present study, we examined the effect of melamine on the follicle development and ovary formation. The data showed that melamine increased reactive oxygen species (ROS levels, and induced granulosa cell apoptosis as well as follicle atresia. To further analyze the mechanism by which melamine induces oxidative stress, the expression and activities of two key antioxidant enzymes superoxide dismutase (SOD and glutathione peroxidase (GPX were analyzed, and the concentration of malondialdehyde (MDA were compared between control and melamine-treated ovaries. The result revealed that melamine changed the expression and activities of SOD and GPX in the melamine-treated mice. Therefore, we demonstrate that melamine causes damage to the ovaries via oxidative stress pathway.
Ivanov, Alexander V.; Bartosch, Birke; Smirnova, Olga A.; Isaguliants, Maria G.; Kochetkov, Sergey N.
Hepatitis C virus (HCV) is the etiological agent accounting for chronic liver disease in approximately 2–3% of the population worldwide. HCV infection often leads to liver fibrosis and cirrhosis, various metabolic alterations including steatosis, insulin and interferon resistance or iron overload, and development of hepatocellular carcinoma or non-Hodgkin lymphoma. Multiple molecular mechanisms that trigger the emergence and development of each of these pathogenic processes have been identified so far. One of these involves marked induction of a reactive oxygen species (ROS) in infected cells leading to oxidative stress. To date, markers of oxidative stress were observed both in chronic hepatitis C patients and in various in vitro systems, including replicons or stable cell lines expressing viral proteins. The search for ROS sources in HCV-infected cells revealed several mechanisms of ROS production and thus a number of cellular proteins have become targets for future studies. Furthermore, during last several years it has been shown that HCV modifies antioxidant defense mechanisms. The aim of this review is to summarize the present state of art in the field and to try to predict directions for future studies. PMID:23358390
Zhang, Dan; Luo, Wan-Ying; Liao, Hua; Wang, Cheng-Fang; Sun, Ying
To investigate the correlation between oxidative stress and PCOS, to provide an evidence for the treatment of PCOS. The levels of maternal serum LPO, MDA, SOD, VE and VC were measured in 30 patients with PCOS (PCOS group 1) and in 30 normal women (control group) by chemicalorimetry. After being measured, the patients with PCOS (PCOS group 1) took VE 0.1 qd x 3 months, VC 0.2 bid x 3 months and Diane-35 (Ethinylestradiol and Cyproterone Acetate Tablets) 1 # qd x 21 d/month x 3 months. The LPO, MDA, SOD, VE and VC were measured after three months. The other 30 patients with PCOS (PCOS group 2) were chosen to take Diane-35 (Ethinylestradiol and Cyproterone Acetate Tablets) 1 qd x 21 d/month x 3 months only. The menstrual cycles were viewed in PCOS group 1 and PCOS group 2 for three months. The levels of maternal serum LPO and MDA in patients with PCOS (PCOS group 1) were significant higher than that in normal women (control group) (P PCOS (PCOS group 1) were lower than that in normal women (control group) (P PCOS group 1 were better than that in PCOS group 2. The PCOS may be related to oxidative stress (the metabolism imbalance of reactive oxygen species). The antioxidants may improve the prognosis of PCOS.
Monique Cristine de Oliveira
Full Text Available Various theories try to explain the biological aging by changing the functions and structure of organic systems and cells. During lifetime, free radicals in the oxidative stress lead to lipid peroxidation of cellular membranes, homeostasis imbalance, chemical residues formation, gene mutations in DNA, dysfunction of certain organelles, and the arise of diseases due to cell death and/or injury. This review describes the action of oxidative stress in the cells aging process, emphasizing the factors such as cellular oxidative damage, its consequences and the main protective measures taken to prevent or delay this process. Tests with antioxidants: vitamins A, E and C, flavonoids, carotenoids and minerals, the practice of caloric restriction and physical exercise, seeking the beneficial effects on human health, increasing longevity, reducing the level of oxidative stress, slowing the cellular senescence and origin of certain diseases, are discussed.Diferentes teorias tentam explicar o envelhecimento biológico através da alteração das funções e estrutura dos sistemas orgânicos e células. Ao longo da vida, os radicais livres presentes no estresse oxidativo conduzem à peroxidação dos lipídios das membranas celulares, desequilíbrio da homeostase, formação de resíduos químicos, mutações gênicas no DNA, disfunção de certas organelas, bem como ao surgimento de doenças devido à lesão e/ou morte celular. Nesta revisão descreve-se a ação do estresse oxidativo no processo de envelhecimento das células, enfatizando fatores como os danos oxidativos celulares, suas conseqüências e as principais medidas protetoras adotadas para se prevenir ou retardar este processo. Testes com antioxidantes: vitaminas A, E e C, flavonóides, carotenóides e minerais; a prática de restrição calórica e exercícios físicos, que buscam efeitos benéficos sobre a saúde humana, aumentando a longevidade, reduzindo o nível de estresse oxidativo
Full Text Available Diabetes mellitus is a common metabolic disorder associated with chronic complications including a state of mild to moderate cognitive impairment, in particular psychomotor slowing and reduced mental flexibility, not attributable to other causes, and shares many symptoms that are best described as accelerated brain ageing. A common theory for aging and for the pathogenesis of this cerebral dysfunctioning in diabetes relates cell death to oxidative stress in strong association to inflammation, and in fact nuclear factor κB (NFκB, a master regulator of inflammation and also a sensor of oxidative stress, has a strategic position at the crossroad between oxidative stress and inflammation. Moreover, metabolic inflammation is, in turn, related to the induction of various intracellular stresses such as mitochondrial oxidative stress, endoplasmic reticulum (ER stress, and autophagy defect. In parallel, blockade of autophagy can relate to proinflammatory signaling via oxidative stress pathway and NFκB-mediated inflammation.
Muriach, María; Flores-Bellver, Miguel; Romero, Francisco J; Barcia, Jorge M
Diabetes mellitus is a common metabolic disorder associated with chronic complications including a state of mild to moderate cognitive impairment, in particular psychomotor slowing and reduced mental flexibility, not attributable to other causes, and shares many symptoms that are best described as accelerated brain ageing. A common theory for aging and for the pathogenesis of this cerebral dysfunctioning in diabetes relates cell death to oxidative stress in strong association to inflammation, and in fact nuclear factor κB (NFκB), a master regulator of inflammation and also a sensor of oxidative stress, has a strategic position at the crossroad between oxidative stress and inflammation. Moreover, metabolic inflammation is, in turn, related to the induction of various intracellular stresses such as mitochondrial oxidative stress, endoplasmic reticulum (ER) stress, and autophagy defect. In parallel, blockade of autophagy can relate to proinflammatory signaling via oxidative stress pathway and NFκB-mediated inflammation.
Takaki, Akinobu; Yamamoto, Kazuhide
Oxidative stress is becoming recognized as a key factor in the progression of chronic liver disease (CLD) and hepatocarcinogenesis. The metabolically important liver is a major reservoir of mitochondria that serve as sources of reactive oxygen species, which are apparently responsible for the initiation of necroinflammation. As a result, CLD could be a major inducer of oxidative stress. Chronic hepatitis C is a powerful generator of oxidative stress, causing a high rate of hepatocarcinogenesi...
Bruce, W Robert; Lee, Owen; Liu, Zhen; Marcon, Norman; Minkin, Salomon; O'Brien, Peter J
We observed an unexpectedly strong association of three different endogenous aldehydes and noted that the association could be explained by multiple reactions in which oxidative stress increased the formation of endogenous aldehydes and endogenous aldehydes increased oxidative stress. These interactions make it reasonable to assess multiple exposures to endogenous oxidative and aldehyde stress with less specific measures such as advanced glycation end-products or protein carbonyls.
Lee, Hyunju; Arnouk, Hilal; Sripathi, Srinivas; Chen, Ping; Zhang, Ruonan; Hunt, Richard C.; Hrushesky, William J. M.; Chung, Hyewon; Lee, Sung Haeng; Jahng, Wan Jin
Identification of biomarker proteins in the retina and the retinal pigment epithelium (RPE) under oxidative stress may imply new insights into signaling mechanisms of retinal degeneration at the molecular level. Proteomic data from an in vivo mice model in constant light and an in vitro oxidative stress model are compared to controls under normal conditions. Our proteomic study shows that prohibitin is involved in oxidative stress signaling in the retina and RPE. The identity of prohibitin in...
Full Text Available Cigarette smokers experience an exaggerated triglyceride (TAG and oxidative stress response to high fat feeding. Exercise training may serve to attenuate the rise in these variables, by improving TAG clearance and antioxidant defense. We compared blood TAG, antioxidant capacity, and oxidative stress biomarkers in exercise trained (>2 hrs per wk and untrained smokers matched for age, in response to a high fat test meal. We report here that low volume exercise training can attenuate postprandial lipid peroxidation, but has little impact on blood TAG and other markers of oxidative stress. Higher volumes of exercise may be needed to allow for clinically meaningful adaptations in postprandial lipemia and oxidative stress.
. Background: There is growing evidence that excess generation of highly reactive free radicals, largely due to hyperglycaemia causes oxidative stress, which further exacerbates the development and ...
Manke, Amruta; Wang, Liying; Rojanasakul, Yon
.... Oxidative stress induced by engineered NP is due to acellular factors such as particle surface, size, composition, and presence of metals, while cellular responses such as mitochondrial respiration...
Cingi Yirün, Merve; Ünal, Kübranur; Altunsoy Şen, Neslihan; Yirün, Onur; Aydemir, Çiğdem; Göka, Erol
Bipolar disorder is one of the most debilitating psychiatric disorders characterized by disruptive episodes of mania/hypomania and depression. Considering the complex role of biological and environmental factors in the etiology of affective disorders, recent studies have focused on oxidative stress, which may damage nerve cell components and take part in pathophysiology. The aim of the present study was to contribute to the data about oxidative stress in bipolar disorder by detecting the total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) levels of manic episode (ME) and euthymic (EU) patients and by comparing these results with those of healthy controls (HCs). The study population consisted of 28 EU outpatients meeting the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for bipolar disorder I and 23 inpatients who were currently hospitalized in a psychiatry ward with the diagnosis of the bipolar disorder ME according to the DSM-5 criteria. Forty-three healthy subjects were included in the study as the control group (HC). Serum TAS, TOS, and OSI levels of all the participants were determined. Statistical analysis of serum TAS, TOS, and OSI levels did not show any significant differences between the ME patients, EU patients, and HCs. Comparison between the bipolar disorder patients (ME+EU) and HC also did not reveal any statistically significant difference between these two groups in terms of serum TAS, TOS, and OSI levels. To date, studies on oxidative stress in bipolar disorder have led to controversial results. In the present study, no statistically significant difference was detected between the oxidative parameters of bipolar disorder patients and HCs. In order to comprehensively evaluate oxidative stress in bipolar disorder, further studies are needed.
Jiang, Shan; Zhang, Dongxin; Huang, Hong; Lei, Yonghong; Han, Yan; Han, Weidong
Background. The aim of this study was to assess the effects of low concentrations of H2O2 on angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro and explore the underlying mechanisms. Methods. HUVECs were cultured and stimulated with different concentrations of H2O2. Flow cytometric analysis was used to select an optimal concentration of H2O2 for the following experiments. Cell proliferation, migration, and tubule formation were evaluated by Cell Counting Kit-8 (CCK-8) assays, scratch wound assays, and Matrigel tubule formation assays, respectively. For gain and loss of function studies, constitutively active MEK5 (CA-MEK5) and ERK5 shRNA lentiviruses were used to activate or knock down extracellular signal-regulated kinase 5 (ERK5). Results. We found that low concentrations of H2O2 promoted HUVECs proliferation, migration, and tubule formation. ERK5 in HUVECs was significantly activated by H2O2. Enhanced ERK5 activity significantly amplified the proangiogenic effects of H2O2; in contrast, ERK5 knock-down abrogated the effects of H2O2. Conclusions. Our results confirmed that low concentrations of H2O2 promoted HUVECs angiogenesis in vitro, and ERK5 is an essential mediator of this process. Therefore, ERK5 may be a potential therapeutic target for promoting angiogenesis and improving graft survival.
Eswari, A Parvathy; Kavitha, S; Banu, J Rajesh; Karthikeyan, O Parthiba; Yeom, Ick-Tae
This study aimed to improve the biomethane potential of dairy waste activated sludge (WAS) by H2O2-acidic pH induced microwave disintegration (HAMW-D) pretreatment approach. The results of HAMW-D compared with the microwave disintegration (MW-D) alone for energy and economic factors. In the two phase disintegration process, the H2O2 concentration of about 0.5mg/g SS under acid pH of 5 was found to be optimum for effective dissociation of Extracellular Polymeric Substances (EPS) matrix. A higher liquefaction of about 46.6% was achieved in HAMW-D when compared to that of MW-D (30%). It subsequently improved the methane yield of about 250mL/g VS in HAMW-D, which was 9.6% higher than MW-D. A net profit of about 49€/ton was achieved for HAMW-D, therefore it is highly recommended for WAS pretreatment. Copyright © 2017 Elsevier Ltd. All rights reserved.
Salmon, Adam B.; Richardson, Arlan; Pérez, Viviana I.
The oxidative stress theory of aging predicts that manipulations that alter oxidative stress/damage will alter aging. The gold standard for determining whether aging is altered is lifespan, i.e., does altering oxidative stress/damage change lifespan? Mice with genetic manipulations in the antioxidant defense system designed to directly address this prediction have, with few exceptions, shown no change in lifespan. However, when these transgenic/knockout mice are tested using models that devel...
Full Text Available Veiko Vengerfeldt,1 Reet Mändar,2,3 Mare Saag,1 Anneli Piir,2 Tiiu Kullisaar2 1Institute of Dental Sciences, Faculty of Medicine, University of Tartu, 2Institute of Biomedicine and Translational Medicine, Faculty of Medicine, University of Tartu, 3Competence Centre on Health Technologies, Tartu, Estonia Background: Apical periodontitis (AP is an inflammatory disease affecting periradicular tissues. It is a widespread condition but its etiopathogenetic mechanisms have not been completely elucidated and the current treatment options are not always successful.Purpose: To compare oxidative stress (OxS levels in the saliva and the endodontium (root canal [RC] contents in patients with different endodontic pathologies and in endodontically healthy subjects.Patients and methods: The study group of this comparison study included 22 subjects with primary chronic apical periodontitis (pCAP, 26 with posttreatment or secondary chronic apical periodontitis (sCAP, eight with acute periapical abscess, 13 with irreversible pulpitis, and 17 healthy controls. Resting saliva samples were collected before clinical treatment. Pulp samples (remnants of the pulp, tooth tissue, and/or previous root filling material were collected under strict aseptic conditions using the Hedström file. The samples were frozen to −80°C until analysis. OxS markers (myeloperoxidase [MPO], oxidative stress index [OSI], 8-isoprostanes [8-EPI] were detected in the saliva and the endodontium. Results: The highest MPO and 8-EPI levels were seen in pCAP and pulpitis, while the highest levels of OSI were seen in pCAP and abscess patients, as well as the saliva of sCAP patients. Controls showed the lowest OxS levels in both RC contents and saliva. Significant positive correlations between OxS markers, periapical index, and pain were revealed. Patients with pain had significantly higher OxS levels in both the endodontium (MPO median 27.9 vs 72.6 ng/mg protein, p=0.004; OSI 6.0 vs 10.4, p<0
Aoi, Wataru; Sakuma, Kunihiro
With advanced of age, production of reactive oxygen species increases in muscle tissues, which causes a continuous elevation of oxidative stress in the muscle. Such oxidative stress brings damage by oxidation of cell components such as lipids, proteins, and DNA. Growing evidences suggest that oxidative stress affects energy metabolism, protein degradation, and apoptosis in the muscle via transcriptional and posttranslation regulation of key proteins, which results in loss of muscle mass and metabolic dysfunction. On the other hand, regular exercise and proper nutrition containing some antioxidant can improve the muscle function by a reduction of excessive oxidative stress. This article describes the influence of oxidative stress on the progress of age-related muscle dysfunction and reviews the effect of countermeasures such as exercise and diet.
Ravi, Sreeram; Peña, Karina A; Chu, Charleen T; Kiselyov, Kirill
Oxidative stress drives cell death in a number of diseases including ischemic stroke and neurodegenerative diseases. A better understanding of how cells recover from oxidative stress is likely to lead to better treatments for stroke and other diseases. The recent evidence obtained in several models ties the process of lysosomal exocytosis to the clearance of protein aggregates and toxic metals. The mechanisms that regulate lysosomal exocytosis, under normal or pathological conditions, are only beginning to emerge. Here we provide evidence for the biphasic effect of oxidative stress on lysosomal exocytosis. Lysosomal exocytosis was measured using the extracellular levels of the lysosomal enzyme beta-hexosaminidase (ß-hex). Low levels or oxidative stress stimulated lysosomal exocytosis, but inhibited it at high levels. Deletion of the lysosomal ion channel TRPML1 eliminated the stimulatory effect of low levels of oxidative stress. The inhibitory effects of oxidative stress appear to target the component of lysosomal exocytosis that is driven by extracellular Ca 2+ . We propose that while moderate oxidative stress promotes cellular repair by stimulating lysosomal exocytosis, at high levels oxidative stress has a dual pathological effect: it directly causes cell damage and impairs damage repair by inhibiting lysosomal exocytosis. Harnessing these adaptive mechanisms may point to pharmacological interventions for diseases involving oxidative proteotoxicity or metal toxicity. Copyright © 2016 Elsevier Ltd. All rights reserved.
Cunningham, Geneva M; Roman, Madeline G; Flores, Lisa C; Hubbard, Gene B; Salmon, Adam B; Zhang, Yiqiang; Gelfond, Jonathan; Ikeno, Yuji
In spite of intensive study, there is still controversy about the free radical or oxidative stress theory of aging, particularly in mammals. Our laboratory has conducted the first detailed studies on the role of thioredoxin (Trx) in the cytosol (Trx1) and in mitochondria (Trx2) on oxidative stress and aging using unique mouse models either overexpressing or down-regulating Trx1 or Trx2. The results generated from our lab and others indicate that: (1) oxidative stress and subsequent changes in signaling pathways could have different pathophysiological impacts at different stages of life; (2) changes in redox-sensitive signaling controlled by levels of oxidative stress and redox state could play more important roles in pathophysiology than accumulation of oxidative damage; (3) changes in oxidative stress and redox state in different cellular compartments (cytosol, mitochondria, or nucleus) could play different roles in pathophysiology during aging, and their combined effects show more impact on aging than changes in either oxidative stress or redox state alone; and (4) the roles of oxidative stress and redox state could have different pathophysiological consequences in different organs/tissues/cells or pathophysiological conditions. To critically test the role of oxidative stress on aging and investigate changes in redox-sensitive signaling pathways, further study is required. Published by Elsevier Inc.
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Inflammation is a common response in the human liver. It is involved in chronic hepatitis, cirrhosis, steatosis, ischemiareperfusion damage, hepatocarcinomas and in the development of metastasis. Reactive oxygen species (ROS production is part of the inflammatory processes. It is implicated in many physiological and pathological situations and can induce mutations in key cancer genes. Normally, this process is prevented by DNA repair enzymatic systems that maintain sequence fidelity during DNA replication. However, overproduction of free radicals in chronic inflammatory diseases is thought to saturate the ability of the cell to repair DNA damage prior to replications. Inflammation-induced genetic damage is not unique to the liver, and it might contribute to the development of mutations in several organs. An example is the chronic inflammatory response in ulcerative colitis that ultimately could lead to neoplasia.
There is compelling evidence to suggest that most known environmental risk factors for HCC development lead to generation of reactive oxygen species (ROS. Indeed, hepatitis C virus (HCV, alcohol and hepatitis B virus (HBV have all been associated with oxidative stress. Direct production of oxidative stress by HCV core protein has been shown. A link between oxidative stress and liver pathogenesis is also supported by the successful use of antioxidant therapy to treat liver injury caused by chronic HCV infection, although it is not currently used for effective therapy. Ethanol metabolism via the alcohol dehydrogenase pathway and microsomal ethanol oxidizing system contribute substantially to the production of acetaldehyde and generation of ROS. HBx via its association with mitochondria has been shown to induce oxidative stress which in turn leads to activation of a
Li, Sha; Tan, Hor-Yue; Wang, Ning; Zhang, Zhang-Jin; Lao, Lixing; Wong, Chi-Woon; Feng, Yibin
A complex antioxidant system has been developed in mammals to relieve oxidative stress. However, excessive reactive species derived from oxygen and nitrogen may still lead to oxidative damage to tissue and organs. Oxidative stress has been considered as a conjoint pathological mechanism, and it contributes to initiation and progression of liver injury. A lot of risk factors, including alcohol, drugs, environmental pollutants and irradiation, may induce oxidative stress in liver, which in turn results in severe liver diseases, such as alcoholic liver disease and non-alcoholic steatohepatitis. Application of antioxidants signifies a rational curative strategy to prevent and cure liver diseases involving oxidative stress. Although conclusions drawn from clinical studies remain uncertain, animal studies have revealed the promising in vivo therapeutic effect of antioxidants on liver diseases. Natural antioxidants contained in edible or medicinal plants often possess strong antioxidant and free radical scavenging abilities as well as anti-inflammatory action, which are also supposed to be the basis of other bioactivities and health benefits. In this review, PubMed was extensively searched for literature research. The keywords for searching oxidative stress were free radicals, reactive oxygen, nitrogen species, anti-oxidative therapy, Chinese medicines, natural products, antioxidants and liver diseases. The literature, including ours, with studies on oxidative stress and anti-oxidative therapy in liver diseases were the focus. Various factors that cause oxidative stress in liver and effects of antioxidants in the prevention and treatment of liver diseases were summarized, questioned, and discussed. PMID:26540040
The reduction of oxidative stress could be achieved in three levels: by lowering exposure to environmental pollutants with oxidizing properties, by increasing levels of endogenous and exogenous antioxidants, or by lowering the generation of oxidative stress by stabilizing mitochondrial energy production and efficiency. Endogenous oxidative stress could be influenced in two ways: by prevention of ROS formation or by quenching of ROS with antioxidants. However, the results of epidemiological studies where people were treated with synthetic antioxidants are inconclusive and contradictory. Recent evidence suggests that antioxidant supplements (although highly recommended by the pharmaceutical industry and taken by many individuals) do not offer sufficient protection against oxidative stress, oxidative damage or increase the lifespan. The key to the future success of decreasing oxidative-stress-induced damage should thus be the suppression of oxidative damage without disrupting the wellintegrated antioxidant defense network. Approach to neutralize free radicals with antioxidants should be changed into prevention of free radical formation. Thus, this paper addresses oxidative stress and strategies to reduce it with the focus on nutritional and psychosocial interventions of oxidative stress prevention, that is, methods to stabilize mitochondria structure and energy efficiency, or approaches which would increase endogenous antioxidative protection and repair systems. PMID:22191011
Li, Sha; Tan, Hor-Yue; Wang, Ning; Zhang, Zhang-Jin; Lao, Lixing; Wong, Chi-Woon; Feng, Yibin
A complex antioxidant system has been developed in mammals to relieve oxidative stress. However, excessive reactive species derived from oxygen and nitrogen may still lead to oxidative damage to tissue and organs. Oxidative stress has been considered as a conjoint pathological mechanism, and it contributes to initiation and progression of liver injury. A lot of risk factors, including alcohol, drugs, environmental pollutants and irradiation, may induce oxidative stress in liver, which in turn results in severe liver diseases, such as alcoholic liver disease and non-alcoholic steatohepatitis. Application of antioxidants signifies a rational curative strategy to prevent and cure liver diseases involving oxidative stress. Although conclusions drawn from clinical studies remain uncertain, animal studies have revealed the promising in vivo therapeutic effect of antioxidants on liver diseases. Natural antioxidants contained in edible or medicinal plants often possess strong antioxidant and free radical scavenging abilities as well as anti-inflammatory action, which are also supposed to be the basis of other bioactivities and health benefits. In this review, PubMed was extensively searched for literature research. The keywords for searching oxidative stress were free radicals, reactive oxygen, nitrogen species, anti-oxidative therapy, Chinese medicines, natural products, antioxidants and liver diseases. The literature, including ours, with studies on oxidative stress and anti-oxidative therapy in liver diseases were the focus. Various factors that cause oxidative stress in liver and effects of antioxidants in the prevention and treatment of liver diseases were summarized, questioned, and discussed.
Full Text Available The reduction of oxidative stress could be achieved in three levels: by lowering exposure to environmental pollutants with oxidizing properties, by increasing levels of endogenous and exogenous antioxidants, or by lowering the generation of oxidative stress by stabilizing mitochondrial energy production and efficiency. Endogenous oxidative stress could be influenced in two ways: by prevention of ROS formation or by quenching of ROS with antioxidants. However, th