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Sample records for exacerbates oxidative stress

  1. Does aspirin-induced oxidative stress cause asthma exacerbation?

    PubMed Central

    Kacprzak, Dorota

    2015-01-01

    Aspirin-induced asthma (AIA) is a distinct clinical syndrome characterized by severe asthma exacerbations after ingestion of aspirin or other non-steroidal anti-inflammatory drugs. The exact pathomechanism of AIA remains unknown, though ongoing research has shed some light. Recently, more and more attention has been focused on the role of aspirin in the induction of oxidative stress, especially in cancer cell systems. However, it has not excluded the similar action of aspirin in other inflammatory disorders such as asthma. Moreover, increased levels of 8-isoprostanes, reliable biomarkers of oxidative stress in expired breath condensate in steroid-naïve patients with AIA compared to AIA patients treated with steroids and healthy volunteers, has been observed. This review is an attempt to cover aspirin-induced oxidative stress action in AIA and to suggest a possible related pathomechanism. PMID:26170841

  2. Exacerbation of pathology by oxidative stress in respiratory and locomotor muscles with Duchenne muscular dystrophy.

    PubMed

    Lawler, John M

    2011-05-01

    Duchenne muscular dystrophy (DMD) is the most devastating type of muscular dystrophy, leading to progressive weakness of respiratory (e.g. diaphragm) and locomotor muscles (e.g. gastrocnemius). DMD is caused by X-linked defects in the gene that encodes for dystrophin, a key scaffolding protein of the dystroglycan complex (DCG) within the sarcolemmal cytoskeleton. As a result of a compromised dystroglycan complex, mechanical integrity is impaired and important signalling proteins (e.g. nNOS, caveolin-3) and pathways are disrupted. Disruption of the dystroglycan complex leads to high susceptibility to injury with repeated, eccentric contractions as well as inflammation, resulting in significant damage and necrosis. Chronic damage and repair cycling leads to fibrosis and weakness. While the link between inflammation with damage and weakness in the DMD diaphragm is unresolved, elevated oxidative stress may contribute to damage, weakness and possibly fibrosis. While utilization of non-specific antioxidant interventions has yielded inconsistent results, recent data suggest that NAD(P)H oxidase could play a pivotal role in elevating oxidative stress via integrated changes in caveolin-3 and stretch-activated channels (SACs). Oxidative stress may act as an amplifier, exacerbating disruption of the dystroglycan complex, upregulation of the inflammatory transcription factor NF-B, and thus functional impairment of force-generating capacity.

  3. Impaired genomic stability and increased oxidative stress exacerbate different features of Ataxia-telangiectasia.

    PubMed

    Ziv, Shelly; Brenner, Ori; Amariglio, Ninette; Smorodinsky, Nechama I; Galron, Ronit; Carrion, Danaise V; Zhang, Weijia; Sharma, Girdhar G; Pandita, Raj K; Agarwal, Manjula; Elkon, Ran; Katzin, Nirit; Bar-Am, Irit; Pandita, Tej K; Kucherlapati, Raju; Rechavi, Gideon; Shiloh, Yosef; Barzilai, Ari

    2005-10-01

    Ataxia-telangiectasia (A-T) is a multisystem, cancer-predisposing genetic disorder caused by deficiency of the ATM protein. To dissect the A-T phenotype, we augmented specific features of the human disease by generating mouse strains that combine Atm deficiency with dysfunction of other proteins. Increasing oxidative stress by combining deficiencies in Atm and superoxide dismutase 1 (Sod1) exacerbated growth retardation and markedly reduced the mean survival time following ionizing radiation. In contrast, increasing genomic instability by combining deficiencies of Atm and the mismatch repair protein Mlh1 caused a moderate increase in radiation sensitivity and dramatic increase in aggressive lymphomas, compared with thes Atm-/- single knockout. Remarkably, Atm, Mlh1 or Mlh1/Atm single or double heterozygosity did not significantly affect the life span of the various genotypes. Mlh1/Atm double null tumors were polyclonal, whereas the tumors in other genotypes were mono- or oligoclonal, demonstrating the high predisposition of thymocytes with this genotype to become malignant. Chromosomal aberrations in the tumors were localized mainly in chromosomes 12 and 15. The genomic region on chromosome 15, which contains the gene for the c-Myc oncoprotein, was commonly amplified, and elevated levels of the c-Myc protein were subsequently observed in the tumors. Our data suggest that impaired genomic instability is an important contributing factor to cancer predisposition in A-T, whereas oxidative stress is more important in the radiation sensitivity and growth retardation facets of this disease.

  4. Innate immune activation by inhaled lipopolysaccharide, independent of oxidative stress, exacerbates silica-induced pulmonary fibrosis in mice.

    PubMed

    Brass, David M; Spencer, Jennifer C; Li, Zhuowei; Potts-Kant, Erin; Reilly, Sarah M; Dunkel, Mary K; Latoche, Joseph D; Auten, Richard L; Hollingsworth, John W; Fattman, Cheryl L

    2012-01-01

    Acute exacerbations of pulmonary fibrosis are characterized by rapid decrements in lung function. Environmental factors that may contribute to acute exacerbations remain poorly understood. We have previously demonstrated that exposure to inhaled lipopolysaccharide (LPS) induces expression of genes associated with fibrosis. To address whether exposure to LPS could exacerbate fibrosis, we exposed male C57BL/6 mice to crystalline silica, or vehicle, followed 28 days later by LPS or saline inhalation. We observed that mice receiving both silica and LPS had significantly more total inflammatory cells, more whole lung lavage MCP-1, MIP-2, KC and IL-1β, more evidence of oxidative stress and more total lung hydroxyproline than mice receiving either LPS alone, or silica alone. Blocking oxidative stress with N-acetylcysteine attenuated whole lung inflammation but had no effect on total lung hydroxyproline. These observations suggest that exposure to innate immune stimuli, such as LPS in the environment, may exacerbate stable pulmonary fibrosis via mechanisms that are independent of inflammation and oxidative stress.

  5. Exacerbation of Alcohol-Induced Oxidative Stress in Rats by Polyunsaturated Fatty Acids and Iron Load

    PubMed Central

    Patere, S. N.; Majumdar, A. S.; Saraf, M. N.

    2011-01-01

    The hypothesis that excessive intake of vegetable oil containing polyunsaturated fatty acids and iron load precipitate alcohol-induced liver damage was investigated in a rat model. In order to elucidate the mechanism underlying this synergism, the serum levels of iron, total protein, serum glutamate pyruvate transaminase, liver thiobarbituric acid reactive substances, and activities of antioxidant enzymes superoxide dismutase, catalase in liver of rats treated with alcohol, polyunsaturated fatty acids and iron per se and in combination were examined. Alcohol was fed to the rats at a level of 10-30% (blood alcohol was maintained between 150-350 mg/dl by using head space gas chromatography), polyunsaturated fatty acids at a level of 15% of diet and carbonyl iron 1.5-2% of diet per se and in combination to different groups for 30 days. Hepatotoxicity was assessed by measuring serum glutamate pyruvate transaminase, which was elevated and serum total protein, which was decreased significantly in rats fed with a combination of alcohol, polyunsaturated fatty acids and iron. It was also associated with increased lipid peroxidation and disruption of antioxidant defense in combination fed rats as compared to rats fed with alcohol or polyunsaturated fatty acids or iron. The present study revealed significant exacerbation of the alcohol-induced oxidative stress in presence of polyunsaturated fatty acids and iron. PMID:22303057

  6. Maternal obesity and malnourishment exacerbate perinatal oxidative stress resulting in diabetogenic programming in F1 offspring.

    PubMed

    Saad, M I; Abdelkhalek, T M; Haiba, M M; Saleh, M M; Hanafi, M Y; Tawfik, S H; Kamel, M A

    2016-06-01

    The effect of in-utero environment on fetal health and survival is long-lasting, and this is known as the fetal origin hypothesis. The oxidative stress state during gestation could play a pivotal role in fetal programming and development of diseases such as diabetes. In this study, we investigated the effect of intra-uterine obesity and malnutrition on oxidative stress markers in pancreatic and peripheral tissues of F1 offspring both prenatally and postnatally. Furthermore, the effect of postnatal diet on oxidative stress profile was evaluated. The results indicated that intra-uterine obesity and malnourishment significantly increased oxidative stress in F1 offspring. Moreover, the programming effect of obesity was more pronounced and protracted than malnutrition. The obesity-induced programming of offspring tissues was independent of high-caloric environment that the offspring endured; however, high-caloric diet potentiated its effect. In addition, pancreas and liver were the most affected tissues by fetal reprogramming both prenatally and postnatally. In conclusion, maternal obesity and malnutrition-induced oxidative stress could predispose offspring to insulin resistance and diabetes.

  7. Pomegranate juice exacerbates oxidative stress and nigrostriatal degeneration in Parkinson’s disease

    PubMed Central

    Tapias, Victor; Cannon, Jason R.; Greenamyre, J. Timothy

    2013-01-01

    Numerous factors contribute to the death of substantia nigra (SN) dopamine (DA) neurons in Parkinson’s disease (PD). Compelling evidence implicates mitochondrial deficiency, oxidative stress, and inflammation as important pathogenic factors in PD. Chronic exposure of rats to rotenone causes a PD-like syndrome, in part by causing oxidative damage and inflammation in SN. Pomegranate juice (PJ) has the greatest composite antioxidant potency index among beverages, and it has been demonstrated to have protective effects in a transgenic model of Alzheimer’s disease. The present study was designed to examine the potential neuroprotective effects of PJ in the rotenone model of PD. Oral administration of PJ did not mitigate or prevent experimental PD but instead increased nigrostriatal terminal depletion, DA neuron loss, the inflammatory response, and caspase activation, thereby heightening neurodegeneration. The mechanisms underlying this effect are uncertain, but the finding that PJ per se enhanced nitrotyrosine, inducible nitric oxide synthase, and activated caspase-3 expression in nigral DA neurons is consistent with its potential pro-oxidant activity. PMID:24315037

  8. A combined marginal deficiency of copper and zinc does not exacerbate oxidant stress asssociated with copper or zinc deficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Both copper deficiency (Cu-def) and zinc deficiency (Zn-def) result in oxidative stress. Thus, an experiment was conducted to determine whether a marginal Zn-def amplified oxidative stress responses to a marginal Cu-def, or vice versa. Weanling male Sprague-Dawley rats were assigned to groups of 10 ...

  9. Nitroxyl exacerbates ischemic cerebral injury and oxidative neurotoxicity.

    PubMed

    Choe, Chi-un; Lewerenz, Jan; Fischer, Gerry; Uliasz, Tracy F; Espey, Michael Graham; Hummel, Friedhelm C; King, Stephen Bruce; Schwedhelm, Edzard; Böger, Rainer H; Gerloff, Christian; Hewett, Sandra J; Magnus, Tim; Donzelli, Sonia

    2009-09-01

    Nitroxyl (HNO) donor compounds function as potent vasorelaxants, improve myocardial contractility and reduce ischemia-reperfusion injury in the cardiovascular system. With respect to the nervous system, HNO donors have been shown to attenuate NMDA receptor activity and neuronal injury, suggesting that its production may be protective against cerebral ischemic damage. Hence, we studied the effect of the classical HNO-donor, Angeli's salt (AS), on a cerebral ischemia/reperfusion injury in a mouse model of experimental stroke and on related in vitro paradigms of neurotoxicity. I.p. injection of AS (40 mumol/kg) in mice prior to middle cerebral artery occlusion exacerbated cortical infarct size and worsened the persistent neurological deficit. AS not only decreased systolic blood pressure, but also induced systemic oxidative stress in vivo indicated by increased isoprostane levels in urine and serum. In vitro, neuronal damage induced by oxygen-glucose-deprivation of mature neuronal cultures was exacerbated by AS, although there was no direct effect on glutamate excitotoxicity. Finally, AS exacerbated oxidative glutamate toxicity - that is, cell death propagated via oxidative stress in immature neurons devoid of ionotropic glutamate receptors. Taken together, our data indicate that HNO might worsen cerebral ischemia-reperfusion injury by increasing oxidative stress and decreasing brain perfusion at concentrations shown to be cardioprotective in vivo.

  10. Mechanical stretch exacerbates the cell death in SH-SY5Y cells exposed to paraquat: mitochondrial dysfunction and oxidative stress.

    PubMed

    Wang, Fang; Franco, Rodrigo; Skotak, Maciej; Hu, Gang; Chandra, Namas

    2014-03-01

    Recent studies suggest that traumatic brain injury (TBI) and pesticide exposure increase the risk of Parkinson's disease (PD), but the molecular mechanisms involved remain unclear. Using an in vitro model of TBI, we evaluated the role of mitochondrial membrane potential (ΔΨm) and mitochondrial reactive oxygen species (ROS) induced by stretch on dopaminergic cell death upon paraquat exposure. Human dopaminergic neuroblastoma SH-SY5Y cells grown on silicone membrane were stretched at mild (25%) and moderate (50%) strain prior to paraquat exposure. We observed that moderate stretch (50% strain) increased the vulnerability of cells to paraquat demonstrated by the loss of plasma membrane integrity (propidium iodide-uptake) and decreased mitochondrial activity (MTT assay). Mitochondrial depolarization occurred immediately after stretch, while mitochondrial ROS increased rapidly and remained elevated for up to 4h after the stretch injury. Intracellular glutathione (GSH) stores were also transiently decreased immediately after moderate stretch. Cells treated with paraquat, or moderate stretch exhibited negligible mitochondrial depolarization at 48h post treatment, whereas in cells stretched prior to paraquat exposure, a significant mitochondrial depolarization occurred compared to samples exposed to either paraquat or stretch. Moderate stretch also increased mitochondrial ROS formation, as well as exacerbated intracellular GSH loss induced by paraquat. Overexpression of manganese superoxide dismutase (MnSOD) markedly diminished the deleterious effects of stretch in paraquat neurotoxicity. Our findings demonstrate that oxidative stress induced by mitochondrial dysfunction plays a critical role in the synergistic toxic effects of stretch (TBI) and pesticide exposure. Mitigation of oxidative stress via mitochondria-targeted antioxidants appears an attractive route for treatment of neurodegeneration mediated by TBI.

  11. Oxidative stress and myocarditis.

    PubMed

    Tada, Yuko; Suzuki, Jun-Ichi

    2016-01-01

    Reactive oxygen species (ROS) such as superoxide anion and hydrogen peroxide are produced highly in myocarditis. ROS, which not only act as effectors for pathogen killing but also mediate signal transduction in the stress responsive pathways, are closely related with both innate and adaptive immunity. On the other hand, oxidative stress overwhelming the capacity of anti-oxidative system generated in severe inflammation has been suggested to damage tissues and exacerbate inflammation. Oxidative stress worsens the autoimmunological process of myocarditis, and suppression of the anti-oxidative system and long-lasting oxidative stress could be one of the pathological mechanisms of cardiac remodeling leading to inflammatory cardiomyopathy. Oxidative stress is considered to be one of the promising treatment targets of myocarditis. Evidences of anti-oxidative treatments in myocarditis have not been fully established. Basic strategies of anti-oxidative treatments include inhibition of ROS production, activation of anti-oxidative enzymes and elimination of generated free radicals. ROS are produced by mitochondrial respiratory chain reactions and enzymes including NADPH oxidases, cyclooxygenase, and xanthine oxidase. Other systems involved in inflammation and stress response, such as NF-κB, Nrf2/Keap1, and neurohumoral factors also influence oxidative stress in myocarditis. The efficacy of anti-oxidative treatments could also depend on the etiology and the phases of myocarditis. We review in this article the pathological significance of ROS and oxidative stress, and the potential anti-oxidative treatments in myocarditis.

  12. Exacerbation of oxidative stress during sickle vaso-occlusive crisis is associated with decreased anti-band 3 autoantibodies rate and increased red blood cell-derived microparticle level: a prospective study.

    PubMed

    Hierso, Régine; Lemonne, Nathalie; Villaescusa, Rinaldo; Lalanne-Mistrih, Marie-Laure; Charlot, Keyne; Etienne-Julan, Maryse; Tressières, Benoit; Lamarre, Yann; Tarer, Vanessa; Garnier, Yohann; Hernandez, Ada Arce; Ferracci, Serge; Connes, Philippe; Romana, Marc; Hardy-Dessources, Marie-Dominique

    2017-03-01

    Painful vaso-occlusive crisis, a hallmark of sickle cell anaemia, results from complex, incompletely understood mechanisms. Red blood cell (RBC) damage caused by continuous endogenous and exogenous oxidative stress may precipitate the occurrence of vaso-occlusive crises. In order to gain insight into the relevance of oxidative stress in vaso-occlusive crisis occurrence, we prospectively compared the expression levels of various oxidative markers in 32 adults with sickle cell anaemia during vaso-occlusive crisis and steady-state conditions. Compared to steady-state condition, plasma levels of free haem, advanced oxidation protein products and myeloperoxidase, RBC caspase-3 activity, as well as the concentrations of total, neutrophil- and RBC-derived microparticles were increased during vaso-occlusive crises, whereas the reduced glutathione content was decreased in RBCs. In addition, natural anti-band 3 autoantibodies levels decreased during crisis and were negatively correlated with the rise in plasma advanced oxidation protein products and RBC caspase-3 activity. These data showed an exacerbation of the oxidative stress during vaso-occlusive crises in sickle cell anaemia patients and strongly suggest that the higher concentration of harmful circulating RBC-derived microparticles and the reduced anti-band 3 autoantibodies levels may be both related to the recruitment of oxidized band 3 into membrane aggregates.

  13. Protective effects of dietary avocado oil on impaired electron transport chain function and exacerbated oxidative stress in liver mitochondria from diabetic rats.

    PubMed

    Ortiz-Avila, Omar; Gallegos-Corona, Marco Alonso; Sánchez-Briones, Luis Alberto; Calderón-Cortés, Elizabeth; Montoya-Pérez, Rocío; Rodriguez-Orozco, Alain R; Campos-García, Jesús; Saavedra-Molina, Alfredo; Mejía-Zepeda, Ricardo; Cortés-Rojo, Christian

    2015-08-01

    Electron transport chain (ETC) dysfunction, excessive ROS generation and lipid peroxidation are hallmarks of mitochondrial injury in the diabetic liver, with these alterations also playing a role in the development of non-alcoholic fatty liver disease (NAFLD). Enhanced mitochondrial sensitivity to lipid peroxidation during diabetes has been also associated to augmented content of C22:6 in membrane phospholipids. Thus, we aimed to test whether avocado oil, a rich source of C18:1 and antioxidants, attenuates the deleterious effects of diabetes on oxidative status of liver mitochondria by decreasing unsaturation of acyl chains of membrane lipids and/or by improving ETC functionality and decreasing ROS generation. Streptozocin-induced diabetes elicited a noticeable increase in the content of C22:6, leading to augmented mitochondrial peroxidizability index and higher levels of lipid peroxidation. Mitochondrial respiration and complex I activity were impaired in diabetic rats with a concomitant increase in ROS generation using a complex I substrate. This was associated to a more oxidized state of glutathione, All these alterations were prevented by avocado oil except by the changes in mitochondrial fatty acid composition. Avocado oil did not prevented hyperglycemia and polyphagia although did normalized hyperlipidemia. Neither diabetes nor avocado oil induced steatosis. These results suggest that avocado oil improves mitochondrial ETC function by attenuating the deleterious effects of oxidative stress in the liver of diabetic rats independently of a hypoglycemic effect or by modifying the fatty acid composition of mitochondrial membranes. These findings might have also significant implications in the progression of NAFLD in experimental models of steatosis.

  14. Prior cadmium exposure improves glucoregulation in diabetic rats but exacerbates effects on metabolic dysregulation, oxidative stress, and hepatic and renal toxicity.

    PubMed

    Singh, Prem Kumar; Baxi, Darshee; Diwedi, Ruchi; Ramachandran, A V

    2012-04-01

    The present study was taken up to assess the role of subchronic exposure to an environmentally relevant dosage of cadmium in type l diabetes. Female rats of the Wistar strain were treated with cadmium (5.12 mg/kg body weight) for 45 days. On day 46, rats were made diabetic by alloxan. After 7 days, diabetes (i.e., animals with serum glucose greater than 300 mg/dL) in the alloxanized animals was confirmed and further experiments were conducted for 15 days. Cadmium pretreatment showed disturbed glucose homeostasis with attendant changes in carbohydrate metabolism, coupled with decrease in food and water intake. Disturbance in carbohydrate metabolism was indicated by altered tissue metabolite load, as marked by a decrease in protein and glycogen contents and increased cholesterol store. Poor glucose clearance subsequent to a glucose challenge under the glucose tolerance test was observed in these animals (0.48/min in control vs. 0.13/min in Cd animals). There was a significantly lower glucose elevation rate in the insulin response test subsequent to an insulin-induced decrease in glucose level in Cd-exposed animals. Elevated oxidative stress was marked by increased lipid peroxidation, decreased antioxidant (both nonenzymatic and enzymatic) levels, and serum markers of hepatic and renal damage. Decreased corticosterone levels, together with increased E2 and reduced P4 levels, were some of the hallmark changes in the serum hormone profile of Cd-exposed animals. Overall, the present results are novel and interesting to open more investigations on animal models of type 1 diabetes with a history of previous Cd exposure.

  15. Haemophilus influenzae and oxidative stress

    PubMed Central

    Harrison, Alistair; Bakaletz, Lauren O.; Munson, Robert S.

    2012-01-01

    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 (COPD), 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 relative to the well-described systems in Escherichia coli. Moreover, we will compare how H. influenzae combats the effect of oxidative stress as a necessary phenotype for its roles as both a successful commensal and pathogen. PMID:22919631

  16. Oxidative stress and anxiety

    PubMed Central

    Rammal, Hassan; Soulimani, Rachid

    2009-01-01

    High O2 consumption, modest antioxidant defenses and a lipid-rich constitution make the brain highly vulnerable to redox imbalances. Oxidative damage in the brain causes nervous system impairment. Recently, oxidative stress has also been implicated in depression, anxiety disorders and high anxiety levels. The findings which establish a link between oxidative stress and pathological anxiety have inspired a number of other recent studies focusing on the link between oxidative status and normal anxiety and also on a possible causal relationship between cellular oxidative stress and emotional stress. This review examines the recent discoveries made on the link between oxidative status and normal anxiety levels and the putative role of oxidative stress in genesis of anxiety. We discuss the different opinions and questions that exist in the field and review the methodological approaches that are being used to determine a causal relationship between oxidative and emotional stress. PMID:20357926

  17. Restraint stress exacerbates cardiac and adipose tissue pathology via β-adrenergic signaling in rats with metabolic syndrome.

    PubMed

    Matsuura, Natsumi; Nagasawa, Kai; Minagawa, Yuji; Ito, Shogo; Sano, Yusuke; Yamada, Yuichiro; Hattori, Takuya; Watanabe, Shogo; Murohara, Toyoaki; Nagata, Kohzo

    2015-05-15

    Restraint stress stimulates sympathetic nerve activity and can affect adiposity and metabolism. However, the effects of restraint stress on cardiovascular and metabolic disorders in metabolic syndrome (MetS) have remained unclear. We investigated the effects of chronic restraint stress and β-adrenergic receptor (β-AR) blockade on cardiac and adipose tissue pathology and metabolic disorders in a rat model of MetS. DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, derived from a cross between Dahl salt-sensitive and Zucker rats. Rats were exposed to restraint stress (restraint cage, 2 h/day) for 4 wk from 9 wk of age with or without daily subcutaneous administration of the β-AR blocker propranolol (2 mg/kg). Age-matched homozygous lean littermates of DS/obese rats (DahlS.Z-Lepr(+)/Lepr(+) rats) served as control animals. Chronic restraint stress exacerbated hypertension as well as left ventricular hypertrophy, fibrosis, diastolic dysfunction, and oxidative stress in a manner sensitive to propranolol treatment. Restraint stress attenuated body weight gain in DS/obese rats, and this effect tended to be reversed by propranolol (P = 0.0682). Restraint stress or propranolol did not affect visceral or subcutaneous fat mass. However, restraint stress potentiated cardiac and visceral adipose tissue inflammation in DS/obese rats, and these effects were ameliorated by propranolol. Restraint stress also exacerbated glucose intolerance, insulin resistance, and abnormal lipid metabolism in a manner sensitive to propranolol. In addition, restraint stress increased urinary norepinephrine excretion, and propranolol attenuated this effect. Our results thus implicate β-ARs in the exacerbation of cardiac and adipose tissue pathology and abnormal glucose and lipid metabolism induced by restraint stress in this model of MetS.

  18. Does psychosocial stress play a role in the exacerbation of psoriasis?

    PubMed

    Hunter, H J A; Griffiths, C E M; Kleyn, C E

    2013-11-01

    It is widely accepted that psychosocial stress can result from the daily strains of living with a diagnosis of psoriasis. There is now an evolving body of work to suggest that psychosocial stress may also play a role in the exacerbation of psoriasis. We discuss the historical evidence supporting a temporal relationship between psychosocial stress and the exacerbation of psoriasis. The underlying pathophysiological mechanisms by which this occurs are largely unknown, but current evidence points towards a role for nerve-related factors, namely their interaction with mast cells and the potentiation of neurogenic inflammation in this regard. It is also likely that the physiological stress response in patients with psoriasis differs from that in healthy individuals, as evidenced by alterations in the hypothalamic-pituitary-adrenal axis and sympathetic-adrenal-medullary system function. Psychological stress results in a redistribution of leucocytes with increased trafficking of inflammatory cells into the skin, which may exacerbate psoriasis. Langerhans cells play a role in the stress response of normal skin; their function in the stress response of patients with psoriasis is open to speculation. We discuss the influence of stress reactivity in patients with psoriasis and the impact of stress reduction strategies in the management of psoriasis. Finally, we suggest potentially fruitful areas for future research.

  19. Staphylococcal response to oxidative stress

    PubMed Central

    Gaupp, Rosmarie; Ledala, Nagender; Somerville, Greg A.

    2012-01-01

    Staphylococci are a versatile genus of bacteria that are capable of causing acute and chronic infections in diverse host species. The success of staphylococci as pathogens is due in part to their ability to mitigate endogenous and exogenous oxidative and nitrosative stress. Endogenous oxidative stress is a consequence of life in an aerobic environment; whereas, exogenous oxidative and nitrosative stress are often due to the bacteria's interaction with host immune systems. To overcome the deleterious effects of oxidative and nitrosative stress, staphylococci have evolved protection, detoxification, and repair mechanisms that are controlled by a network of regulators. In this review, we summarize the cellular targets of oxidative stress, the mechanisms by which staphylococci sense oxidative stress and damage, oxidative stress protection and repair mechanisms, and regulation of the oxidative stress response. When possible, special attention is given to how the oxidative stress defense mechanisms help staphylococci control oxidative stress in the host. PMID:22919625

  20. Erythropoietin and oxidative stress.

    PubMed

    Maiese, Kenneth; Chong, Zhao Zhong; Hou, Jinling; Shang, Yan Chen

    2008-05-01

    Unmitigated oxidative stress can lead to diminished cellular longevity, accelerated aging, and accumulated toxic effects for an organism. Current investigations further suggest the significant disadvantages that can occur with cellular oxidative stress that can lead to clinical disability in a number of disorders, such as myocardial infarction, dementia, stroke, and diabetes. New therapeutic strategies are therefore sought that can be directed toward ameliorating the toxic effects of oxidative stress. Here we discuss the exciting potential of the growth factor and cytokine erythropoietin for the treatment of diseases such as cardiac ischemia, vascular injury, neurodegeneration, and diabetes through the modulation of cellular oxidative stress. Erythropoietin controls a variety of signal transduction pathways during oxidative stress that can involve Janus-tyrosine kinase 2, protein kinase B, signal transducer and activator of transcription pathways, Wnt proteins, mammalian forkhead transcription factors, caspases, and nuclear factor kappaB. Yet, the biological effects of erythropoietin may not always be beneficial and may be poor tolerated in a number of clinical scenarios, necessitating further basic and clinical investigations that emphasize the elucidation of the signal transduction pathways controlled by erythropoietin to direct both successful and safe clinical care.

  1. Stress, social support, emotional regulation, and exacerbation of diffuse plaque psoriasis.

    PubMed

    Picardi, A; Mazzotti, E; Gaetano, P; Cattaruzza, M S; Baliva, G; Melchi, C F; Biondi, M; Pasquini, P

    2005-01-01

    The authors' aim was to investigate the role of stressful events, perceived social support, attachment security, and alexithymia in triggering exacerbations of diffuse plaque psoriasis. Inpatients experiencing a recent exacerbation of diffuse plaque psoriasis (N=33) were compared with inpatients with skin conditions believed to have a negligible psychosomatic component (N=73). Stressful events during the last year were assessed with Paykel's Interview for Recent Life Events. Attachment style, alexithymia, and perceived social support were assessed with the Experiences in Close Relationships questionnaire, the Toronto Alexithymia Scale, and the Multidimensional Scale of Perceived Social Support, respectively. Multiple logistic regression analysis was used to control for age, gender, education, marital status, and alcohol consumption. In relation to comparison subjects, the patients with psoriasis had lower perceived social support and higher attachment-related avoidance. Also, they were more likely to have high alexithymic characteristics. There were no differences between the patients with psoriasis and the comparison subjects in scores on the Experiences in Close Relationships anxiety scale, the total number of stressful events, and the number of undesirable, uncontrollable, or major events. Although caution should be applied in generalizing these findings to outpatients, this study suggests that alexithymia, attachment-related avoidance, and poor social support might increase susceptibility to exacerbations of diffuse plaque psoriasis, possibly through impaired emotional regulation. Several physiological mechanisms involving the neuroendocrine and the immune system might mediate the interplay between stress, personality, and diffuse plaque psoriasis.

  2. A Molecular Web: Endoplasmic Reticulum Stress, Inflammation, and Oxidative Stress

    PubMed Central

    Chaudhari, Namrata; Talwar, Priti; Parimisetty, Avinash; Lefebvre d’Hellencourt, Christian; Ravanan, Palaniyandi

    2014-01-01

    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

  3. Pulmonary oxidative stress, inflammation and dysregulated iron homeostatis in rat models of cardiovascular disease

    EPA Science Inventory

    Underlying cardiovascular disease (CVD) is considered a risk factor for the exacerbation of air pollution health effects. Therefore, rodent models of CVD are increasingly used to examine mechanisms ofvariation in susceptibility. Pulmonary oxidative stress, inflammation and altere...

  4. Oxidative stress & male infertility.

    PubMed

    Makker, Kartikeya; Agarwal, Ashok; Sharma, Rakesh

    2009-04-01

    The male factor is considered a major contributory factor to infertility. Apart from the conventional causes for male infertility such as varicocoele, cryptorchidism, infections, obstructive lesions, cystic fibrosis, trauma, and tumours, a new and important cause has been identified: oxidative stress. Oxidative stress is a result of the imbalance between reactive oxygen species (ROS) and antioxidants in the body. It is a powerful mechanism that can lead to sperm damage, deformity and eventually, male infertility. This review discusses the physiological need for ROS and their role in normal sperm function. It also highlights the mechanism of production and the pathophysiology of ROS in relation to the male reproductive system and enumerate the benefits of incorporating antioxidants in clinical and experimental settings.

  5. Oxidative Stress in Malaria

    PubMed Central

    Percário, Sandro; Moreira, Danilo R.; Gomes, Bruno A. Q.; Ferreira, Michelli E. S.; Gonçalves, Ana Carolina M.; Laurindo, Paula S. O. C.; Vilhena, Thyago C.; Dolabela, Maria F.; Green, Michael D.

    2012-01-01

    Malaria is a significant public health problem in more than 100 countries and causes an estimated 200 million new infections every year. Despite the significant effort to eradicate this dangerous disease, lack of complete knowledge of its physiopathology compromises the success in this enterprise. In this paper we review oxidative stress mechanisms involved in the disease and discuss the potential benefits of antioxidant supplementation as an adjuvant antimalarial strategy. PMID:23208374

  6. CVD and Oxidative Stress

    PubMed Central

    Cervantes Gracia, Karla; Llanas-Cornejo, Daniel; Husi, Holger

    2017-01-01

    Nowadays, it is known that oxidative stress plays at least two roles within the cell, the generation of cellular damage and the involvement in several signaling pathways in its balanced normal state. So far, a substantial amount of time and effort has been expended in the search for a clear link between cardiovascular disease (CVD) and the effects of oxidative stress. Here, we present an overview of the different sources and types of reactive oxygen species in CVD, highlight the relationship between CVD and oxidative stress and discuss the most prominent molecules that play an important role in CVD pathophysiology. Details are given regarding common pharmacological treatments used for cardiovascular distress and how some of them are acting upon ROS-related pathways and molecules. Novel therapies, recently proposed ROS biomarkers, as well as future challenges in the field are addressed. It is apparent that the search for a better understanding of how ROS are contributing to the pathophysiology of CVD is far from over, and new approaches and more suitable biomarkers are needed for the latter to be accomplished. PMID:28230726

  7. Oxidative Stress in Myopia

    PubMed Central

    Francisco, Bosch-Morell; Salvador, Mérida; Amparo, Navea

    2015-01-01

    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

  8. Oxidative stress in myopia.

    PubMed

    Francisco, Bosch-Morell; Salvador, Mérida; Amparo, Navea

    2015-01-01

    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.

  9. Oxidative stress and ageing.

    PubMed

    Birch-Machin, M A; Bowman, A

    2016-10-01

    Oxidative stress is the resultant damage due to redox imbalances (increase in destructive free radicals [reactive oxygen species (ROS)] and reduction in antioxidant protection/pathways) and is linked to ageing in many tissues including skin. In ageing skin there are bioenergetic differences between keratinocytes and fibroblasts which provide a potential ageing biomarker. The differences in skin bioenergy are part of the mitochondrial theory of ageing which remains one of the most widely accepted ageing theories describing subsequent increasing free radical generation. Mitochondria are the major source of cellular oxidative stress and form part of the vicious cycle theory of ageing. External and internal sources of oxidative stress include UVR/IR, pollution (environment), lifestyle (exercise and diet), alcohol and smoking all of which may potentially impact on skin although many exogenous actives and endogenous antioxidant defence systems have been described to help abrogate the increased stress. This also links to differences in skin cell types in terms of the UVR action spectrum for nuclear and mitochondrial DNA damage (the latter a previously described UVR biomarker in skin). Recent work associates bioenergy production and oxidative stress with pigment production thereby providing another additional potential avenue for targeted anti-ageing intervention in skin. This new data supporting the detrimental effects of the numerous wavelengths of UVR may aid in the development of cosmetic/sunscreen design to reduce the effects of photoageing. Recently, complex II of the mitochondrial electron transport chain appears to be more important than previously thought in the generation of free radicals (suggested predominantly by non-human studies). We investigated the relationship between complex II and ageing using human skin as a model tissue. The rate of complex II activity per unit of mitochondria was determined in fibroblasts and keratinocytes cultured from skin covering

  10. Doxorubicin induced myocardial injury is exacerbated following ischaemic stress via opening of the mitochondrial permeability transition pore

    SciTech Connect

    Gharanei, M.; Hussain, A.; Janneh, O.; Maddock, H.L.

    2013-04-15

    Chemotherapeutic agents such as doxorubicin are known to cause or exacerbate cardiovascular cell death when an underlying heart condition is present. However, the mechanism of doxorubicin-induced cardiotoxicity is unclear. Here we assess the cardiotoxic effects of doxorubicin in conditions of myocardial ischaemia reperfusion and the mechanistic basis of protection, in particular the role of the mitochondrial permeability transition pore (mPTP) in such protection. The effects of doxorubicin (1 μM) ± cyclosporine A (CsA, 0.2 μM; inhibits mPTP) were investigated in isolated male Sprague–Dawley rats using Langendorff heart and papillary muscle contraction models subjected to simulated ischaemia and reperfusion injury. Isolated rat cardiac myocytes were used in an oxidative stress model to study the effects of drug treatment on mPTP by confocal microscopy. Western blot analysis evaluated the effects of drug treatment on p-Akt and p-Erk 1/2 levels. Langendorff and the isometric contraction models showed a detrimental effect of doxorubicin throughout reperfusion/reoxygenation as well as increased p-Akt and p-Erk levels. Interestingly, CsA not only reversed the detrimental effects of doxorubicin, but also reduced p-Akt and p-Erk levels. In the sustained oxidative stress assay to study mPTP opening, doxorubicin decreased the time taken to depolarization and hypercontracture, but these effects were delayed in the presence of CsA. Collectively, our data suggest for the first that doxorubicin exacerbates myocardial injury in an ischaemia reperfusion model. If the inhibition of mPTP ameliorates the cardiotoxic effects of doxorubicin, then more selective inhibitors of mPTP should be further investigated for their utility in patients receiving doxorubicin. - Highlights: ► Doxorubicin exacerbates myocardial ischaemia reperfusion injury. ► Co-treatment with CsA protects against doxorubicin induced myocardial injury. ► CsA delays doxorubicin induced mPTP opening in laser

  11. Restraint stress exacerbates alcohol-induced reproductive toxicity in male rats.

    PubMed

    Priya, P Hari; Girish, B P; Reddy, P Sreenivasula

    2014-12-01

    Cumulative exposure to multiple stresses may lead to aggravating the toxicity of each stress, qualitatively or quantitatively altering biological responses because of toxicological interaction. In this study, we intended to determine the possible effects of restraint stress on reproductive toxicity due to ethanol usage in male rats. Early pubertal male Wistar rats were subjected to either restraint stress (5 h/day) or alcohol intoxication (2 mg/kg body weight) or both for 60 days. Body weights of control and experimental rats were similar during the 60 days of this study. Testes were harvested, weighed, and prepared for enzyme assays, and cauda epididymides were isolated for the determination of density, motility, and viability of stored spermatozoa. Restraint stress or alcohol treatment significantly reduced testis weight and caused significant reductions in steroidogenesis and spermatogenesis. Mean density, motility, and viability of stored spermatozoa were reduced in experimental rats. Plasma testosterone concentrations in rats subjected to restraint stress or alcohol were decreased compared with those of controls, concomitant with increased concentrations of LH and FSH in experimental rats. These data suggest that sub-chronic exposure to restraint stress or alcohol contribute to reduce testicular and epididymal function in exposed rats. The study also suggests that restraint stress exacerbates alcohol-induced reproductive toxicity in rats.

  12. Oxidative Stress, Nitric Oxide, and Diabetes

    PubMed Central

    Pitocco, Dario; Zaccardi, Francesco; Di Stasio, Enrico; Romitelli, Federica; Santini, Stefano A.; Zuppi, Cecilia; Ghirlanda, Giovanni

    2010-01-01

    In the recent decades, oxidative stress has become focus of interest in most biomedical disciplines and many types of clinical research. Increasing evidence from research on several diseases show that oxidative stress is associated with the pathogenesis of diabetes, obesity, cancer, ageing, inflammation, neurodegenerative disorders, hypertension, apoptosis, cardiovascular diseases, and heart failure. Based on this research, the emerging concept is that oxidative stress is the “final common pathway”, through which risk factors of several diseases exert their deleterious effects. Oxidative stress causes a complex dysregulation of cell metabolism and cell-cell homeostasis. In this review, we discuss the role of oxidative stress in the pathogenesis of insulin resistance and beta-cell dysfunction. These are the two most relevant mechanisms in the pathophysiology of type 2 diabetes, and in the pathogenesis of diabetic vascular complications, the leading cause of death in diabetic patients. PMID:20703435

  13. Oxidative stress, nitric oxide, and diabetes.

    PubMed

    Pitocco, Dario; Zaccardi, Francesco; Di Stasio, Enrico; Romitelli, Federica; Santini, Stefano A; Zuppi, Cecilia; Ghirlanda, Giovanni

    2010-01-01

    In the recent decades, oxidative stress has become focus of interest in most biomedical disciplines and many types of clinical research. Increasing evidence from research on several diseases show that oxidative stress is associated with the pathogenesis of diabetes, obesity, cancer, ageing, inflammation, neurodegenerative disorders, hypertension, apoptosis, cardiovascular diseases, and heart failure. Based on this research, the emerging concept is that oxidative stress is the "final common pathway", through which risk factors of several diseases exert their deleterious effects. Oxidative stress causes a complex dysregulation of cell metabolism and cell-cell homeostasis. In this review, we discuss the role of oxidative stress in the pathogenesis of insulin resistance and beta-cell dysfunction. These are the two most relevant mechanisms in the pathophysiology of type 2 diabetes, and in the pathogenesis of diabetic vascular complications, the leading cause of death in diabetic patients.

  14. BRCA1 and Oxidative Stress

    PubMed Central

    Yi, Yong Weon; Kang, Hyo Jin; Bae, Insoo

    2014-01-01

    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. PMID:24704793

  15. Hypoxia-Induced Oxidative Stress Modulation with Physical Activity

    PubMed Central

    Debevec, Tadej; Millet, Grégoire P.; Pialoux, Vincent

    2017-01-01

    Increased oxidative stress, defined as an imbalance between prooxidants and antioxidants, resulting in molecular damage and disruption of redox signaling, is associated with numerous pathophysiological processes and known to exacerbate chronic diseases. Prolonged systemic hypoxia, induced either by exposure to terrestrial altitude or a reduction in ambient O2 availability is known to elicit oxidative stress and thereby alter redox balance in healthy humans. The redox balance modulation is also highly dependent on the level of physical activity. For example, both high-intensity exercise and inactivity, representing the two ends of the physical activity spectrum, are known to promote oxidative stress. Numerous to-date studies indicate that hypoxia and exercise can exert additive influence upon redox balance alterations. However, recent evidence suggests that moderate physical activity can attenuate altitude/hypoxia-induced oxidative stress during long-term hypoxic exposure. The purpose of this review is to summarize recent findings on hypoxia-related oxidative stress modulation by different activity levels during prolonged hypoxic exposures and examine the potential mechanisms underlying the observed redox balance changes. The paper also explores the applicability of moderate activity as a strategy for attenuating hypoxia-related oxidative stress. Moreover, the potential of such moderate intensity activities used to counteract inactivity-related oxidative stress, often encountered in pathological, elderly and obese populations is also discussed. Finally, future research directions for investigating interactive effects of altitude/hypoxia and exercise on oxidative stress are proposed. PMID:28243207

  16. Do interactions between stress and immune responses lead to symptom exacerbations in irritable bowel syndrome?

    PubMed

    O'Malley, Dervla; Quigley, Eamonn M M; Dinan, Timothy G; Cryan, John F

    2011-10-01

    Irritable bowel syndrome (IBS) is a common, debilitating gastrointestinal (GI) disorder, with a worldwide prevalence of between 10% and 20%. This functional gut disorder is characterized by episodic exacerbations of a cluster of symptoms including abdominal pain, bloating and altered bowel habit, including diarrhea and/or constipation. Risk factors for the development of IBS include a family history of the disorder, childhood trauma and prior gastrointestinal infection. It is generally accepted that brain-gut axis dysfunction is fundamental to the development of IBS; however the underlying pathophysiological mechanisms remain elusive. Additional considerations in comprehending the chronic relapsing pattern that typifies IBS symptoms are the effects of both psychosocial and infection-related stresses. Indeed, co-morbidity with mood disorders such as depression and anxiety is common in IBS. Accumulating evidence points to a role for a maladaptive stress response in the initiation, persistence and severity of IBS-associated symptom flare-ups. Moreover, mechanistically, the stress-induced secretion of corticotropin-releasing factor (CRF) is known to mediate changes in GI function. Activation of the immune system also appears to be important in the generation of IBS symptoms and increasing evidence now implicates low-grade inflammation or immune activation in IBS pathophysiology. There is a growing body of research focused on understanding at a molecular, cellular and in vivo level, the relationship between the dysregulated stress response and immune system alterations (either individually or in combination) in the etiology of IBS and to the occurrence of symptoms.

  17. Dietary trimethylamine N-oxide exacerbates impaired glucose tolerance in mice fed a high fat diet.

    PubMed

    Gao, Xiang; Liu, Xiaofang; Xu, Jie; Xue, Changhu; Xue, Yong; Wang, Yuming

    2014-10-01

    Trimethylamine N-oxide (TMAO) is an oxidation product of trimethylamine (TMA) and is present in many aquatic foods. Here, we investigated the effects of TMAO on glucose tolerance in high fat diet (HFD)-fed mice. Male C57BL/6 mice were randomly assigned to the control, high fat (HF), and TMAO groups. The HF group was fed a diet containing 25% fat, and the TMAO group was fed the HFD plus 0.2% TMAO for 4 weeks. After 3 weeks of feeding, oral glucose tolerance tests were performed. Dietary TMAO increased fasting insulin levels and homeostasis model assessment-estimated insulin resistance (HOMA-IR) and exacerbated the impaired glucose tolerance in HFD-fed mice. These effects were associated with the expression of genes related to the insulin signal pathway, glycogen synthesis, gluconeogenesis and glucose transport in liver. mRNA levels of the pro-inflammatory cytokine MCP-1 increased significantly and of the anti-inflammatory cytokine IL-10 greatly decreased in adipose tissue. Our results suggest that dietary TMAO exacerbates impaired glucose tolerance, obstructs the hepatic insulin signaling pathway, and causes adipose tissue inflammation in mice fed a high fat diet.

  18. Stress in the Adult Rat Exacerbates Muscle Pain Induced by Early-Life Stress

    PubMed Central

    Alvarez, Pedro; Green, Paul G.; Levine, Jon D.

    2013-01-01

    Background Early-life stress and exposure to stressful stimuli play a major role in the development of chronic widespread pain in adults. However, how they interact in chronic pain syndromes remains unclear. Methods Dams and neonatal litters were submitted to a restriction of nesting material (neonatal limited bedding, NLB) for one week. As adults, these rats were exposed to a painless sound stress protocol. The involvement of sympathoadrenal catecholamines, interleukin 6 (IL-6) and tumor necrosis alpha (TNFα) in nociception, was evaluated through of behavioral and ELISA assays, surgical interventions and intrathecal antisense treatments. Results Adult NLB rats exhibited mild muscle hyperalgesia, which was markedly aggravated by sound stress (peaking 15 days after exposure). Adrenal medullectomy did not modify hyperalgesia in NLB rats but prevented its aggravation by sound stress. Sustained administration of epinephrine to NLB rats mimicked sound stress effect. Intrathecal treatment with antisense directed to IL-6-receptor subunit gp130, but not to TNFα type 1 receptor (TNFR1), inhibited hyperalgesia in NLB rats. However, antisense against either gp130 or TNFR1 inhibited sound stress-induced enhancement of hyperalgesia. Compared to control rats, NLB rats exhibit increased plasma levels of IL-6 but decreased levels of TNFα, whereas sound stress increases IL-6 plasma levels in control but not in NLB rats. Conclusions Early-life stress induces a persistent elevation of IL-6, hyperalgesia and susceptibility to chronic muscle pain, which is unveiled by exposure to stress in adults. This probably depends on an interaction between adrenal catecholamines and pro-inflammatory cytokines acting at muscle nociceptor level. PMID:23706525

  19. Oxidative stress and hypertension.

    PubMed

    Harrison, David G; Gongora, Maria Carolina

    2009-05-01

    This review has summarized some of the data supporting a role of ROS and oxidant stress in the genesis of hypertension. There is evidence that hypertensive stimuli, such as high salt and angiotensin II, promote the production of ROS in the brain, the kidney, and the vasculature and that each of these sites contributes either to hypertension or to the untoward sequelae of this disease. Although the NADPH oxidase in these various organs is a predominant source, other enzymes likely contribute to ROS production and signaling in these tissues. A major clinical challenge is that the routinely used antioxidants are ineffective in preventing or treating cardiovascular disease and hypertension. This is likely because these drugs are either ineffective or act in a non-targeted fashion, such that they remove not only injurious ROS Fig. 5. Proposed role of T cells in the genesis of hypertension and the role of the NADPH oxidase in multiple cells/organs in modulating this effect. In this scenario, angiotensin II stimulates an NADPH oxidase in the CVOs of the brain, increasing sympathetic outflow. Sympathetic nerve terminals in lymph nodes activate T cells, and angiotensin II also directly activates T cells. These stimuli also activate expression of homing signals in the vessel and likely the kidney, which attract T cells to these organs. T cells release cytokines that stimulate the vessel and kidney NADPH oxidases, promoting vasoconstriction and sodium retention. SFO, subfornical organ. 630 Harrison & Gongora but also those involved in normal cell signaling. A potentially important and relatively new direction is the concept that inflammatory cells such as T cells contribute to hypertension. Future studies are needed to understand the interaction of T cells with the CNS, the kidney, and the vasculature and how this might be interrupted to provide therapeutic benefit.

  20. Oxidative stress in Parkinson's disease.

    PubMed

    Nikam, Shashikant; Nikam, Padmaja; Ahaley, S K; Sontakke, Ajit V

    2009-01-01

    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 thiobarbituric acid reactive substances, nitric oxide in the form of nitrite & nitrate. Enzymatic antioxidants in the form of superoxide dismutase, glutathione peroxidase, catalase, ceruloplasmin and non enzymatic antioxidant vitamins e.g. vitamin E and C in either serum or plasma or erythrocyte in 40 patients of Parkinson's disease in the age group 40-80 years. Trace elements e.g. copper, zinc and selenium were also estimated. Plasma thiobarbituric acid reactive substances and nitric oxide levels were Significantly high but superoxide dismutase, glutathione peroxidase, catalase, ceruloplasmin, vitamin-E, vitamin-C, copper, zinc and selenium levels were significantly low in Parkinson's disease when compared with control subjects. Present study showed that elevated oxidative stress may be playing a role in dopaminergic neuronal loss in substentia nigra pars compacta and involved in pathogenesis of the Parkinson's disease.

  1. Chronic stress exacerbates neuropathic pain via the integration of stress-affect-related information with nociceptive information in the central nucleus of the amygdala.

    PubMed

    Li, Ming-Jia; Liu, Ling-Yu; Chen, Lin; Cai, Jie; Wan, You; Xing, Guo-Gang

    2017-04-01

    Exacerbation of pain by chronic stress and comorbidity of pain with stress-related psychiatric disorders, including anxiety and depression, represent significant clinical challenges. However, the underlying mechanisms still remain unclear. Here, we investigated whether chronic forced swim stress (CFSS)-induced exacerbation of neuropathic pain is mediated by the integration of stress-affect-related information with nociceptive information in the central nucleus of the amygdala (CeA). We first demonstrated that CFSS indeed produces both depressive-like behaviors and exacerbation of spared nerve injury (SNI)-induced mechanical allodynia in rats. Moreover, we revealed that CFSS induces both sensitization of basolateral amygdala (BLA) neurons and augmentation of long-term potentiation (LTP) at the BLA-CeA synapse and meanwhile, exaggerates both SNI-induced sensitization of CeA neurons and LTP at the parabrachial (PB)-CeA synapse. In addition, we discovered that CFSS elevates SNI-induced functional up-regulation of GluN2B-containing NMDA (GluN2B-NMDA) receptors in the CeA, which is proved to be necessary for CFSS-induced augmentation of LTP at the PB-CeA synapse and exacerbation of pain hypersensitivity in SNI rats. Suppression of CFSS-elicited depressive-like behaviors by antidepressants imipramine or ifenprodil inhibits the CFSS-induced exacerbation of neuropathic pain. Collectively, our findings suggest that CFSS potentiates synaptic efficiency of the BLA-CeA pathway, leading to the activation of GluN2B-NMDA receptors and sensitization of CeA neurons, which subsequently facilitate pain-related synaptic plasticity of the PB-CeA pathway, thereby exacerbating SNI-induced neuropathic pain. We conclude that chronic stress exacerbates neuropathic pain via the integration of stress-affect-related information with nociceptive information in the CeA.

  2. The metabolomics of oxidative stress.

    PubMed

    Noctor, Graham; Lelarge-Trouverie, Caroline; Mhamdi, Amna

    2015-04-01

    Oxidative stress resulting from increased availability of reactive oxygen species (ROS) is a key component of many responses of plants to challenging environmental conditions. The consequences for plant metabolism are complex and manifold. We review data on small compounds involved in oxidative stress, including ROS themselves and antioxidants and redox buffers in the membrane and soluble phases, and we discuss the wider consequences for plant primary and secondary metabolism. While metabolomics has been exploited in many studies on stress, there have been relatively few non-targeted studies focused on how metabolite signatures respond specifically to oxidative stress. As part of the discussion, we present results and reanalyze published datasets on metabolite profiles in catalase-deficient plants, which can be considered to be model oxidative stress systems. We emphasize the roles of ROS-triggered changes in metabolites as potential oxidative signals, and discuss responses that might be useful as markers for oxidative stress. Particular attention is paid to lipid-derived compounds, the status of antioxidants and antioxidant breakdown products, altered metabolism of amino acids, and the roles of phytohormone pathways.

  3. Exhaled Nitric Oxide, Lung Function, and Exacerbations in Wheezy Infants and Toddlers

    PubMed Central

    Debley, Jason S.; Stamey, David C.; Cochrane, Elizabeth S.; Gama, Kim L.; Redding, Gregory J.

    2010-01-01

    Background There are limited data assessing the relationship between fractional concentration of exhaled nitric oxide (FENO) and lung function or exacerbations in infants with recurrent wheezing. Objectives In a longitudinal pilot study of children < 2 years old we assessed whether baseline FENO was associated with lung function, bronchodilator responsiveness, changes in lung function, or subsequent exacerbations of wheezing. Methods Forced expiratory flows and volumes using the raised-volume rapid thoracic compression method were measured in 44 infants and toddlers (mean age 15.7 mos.) with recurrent wheezing. Single-breath exhaled nitric oxide (SB-eNO) was measured at 50 mL/sec. Lung function was again measured 6 months after enrollment. Results At enrollment FEV0.5, FEF25-75, and FEF75 z-scores for the cohort were significantly less than zero. There was no correlation between enrollment SB-eNO and enrollment lung function measures. SB-eNO was higher in infants with bronchodilator responsiveness (46.1 vs. 23.6 ppb, p<0.001), and was associated with a decline in FEV0.5 (r = -.54, P = 0.001), FEF25-75 (r = -0.6, P < 0.001), and FEF75 (r = -0.55, P = 0.001) over 6 months. A 10ppb increase in SB-eNO was associated with a 0.4 z-score decline in FEV0.5, a 0.4 z-score decline in FEF25-75, and a 0.42 z-score decline in FEF75. SB-eNO was superior to lung function and bronchodilator responsivenss in predicting subsequent wheezing treated with systemic steroids. Conclusions SB-eNO may predict changes in lung function and risk of future wheezing, and holds promise as a biomarker to predict asthma in wheezy infants and toddlers. PMID:20462633

  4. Oxidative stress and carbon metabolism influence Aspergillus flavus transcriptome composition and secondary metabolite production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Contamination of crops with aflatoxin is a serious threat to global food safety. Aflatoxin production by Aspergillus flavus has been shown to be exacerbated by drought stress in the field and by oxidative stress in vitro. We examined the transcriptomes of three toxigenic and three atoxigenic isolate...

  5. Stress exacerbates neuron loss and microglia proliferation in a rat model of excitotoxic lower motor neuron injury

    PubMed Central

    Puga, Denise A.; Tovar, C. Amy; Guan, Zhen; C.Gensel, John; Lyman, Matthew S.; McTigue, Dana M.; Popovich, Phillip G.

    2015-01-01

    All individuals experience stress and hormones (e.g., glucocorticoids/GCs) released during stressful events can affect the structure and function of neurons. These effects of stress are best characterized for brain neurons; however, the mechanisms controlling the expression and binding affinity of glucocorticoid receptors in the spinal cord are different than those in the brain. Accordingly, whether stress exerts unique effects on spinal cord neurons, especially in the context of pathology, is unknown. Using a controlled model of focal excitotoxic lower motor neuron injury in rats, we examined the effects of acute or chronic variable stress on spinal cord motor neuron survival and glial activation. New data indicate that stress exacerbates excitotoxic spinal cord motor neuron loss and associated activation of microglia. In contrast, hypertrophy and hyperplasia of astrocytes and NG2+ glia were unaffected or were modestly suppressed by stress. Although excitotoxic lesions cause significant motor neuron loss and stress exacerbates this pathology, overt functional impairment did not develop in the relevant forelimb up to one week post-lesion. These data indicate that stress is a disease-modifying factor capable of altering neuron and glial responses to pathological challenges in the spinal cord. PMID:26100488

  6. Binge Ethanol and MDMA Combination Exacerbates Toxic Cardiac Effects by Inducing Cellular Stress

    PubMed Central

    Navarro-Zaragoza, Javier; Ros-Simó, Clara; Milanés, María-Victoria; Valverde, Olga; Laorden, María-Luisa

    2015-01-01

    Binge drinking is a common pattern of ethanol consumption among young people. Binge drinkers are especially susceptible to brain damage when other substances are co-administered, in particular 3,4 methylendioxymethamphetamine (MDMA). The aim of the present work was to study the mechanisms implicated in the adaptive changes observed after administration of these drugs of abuse. So, we have evaluated the cardiac sympathetic activity and the expression and activation of heat shock protein 27 (HSP27), after voluntary binge ethanol consumption, alone and in combination with MDMA. Both parameters are markers of stressful situations and they could be modified inducing several alterations in different systems. Adolescent mice received MDMA, ethanol or both (ethanol plus MDMA). Drinking in the dark (DID) procedure was used as a model of binge. Noradrenaline (NA) turnover, tyrosine hydroxylase (TH), TH phosphorylated at serine 31 and HSP27 expression and its phosphorylation at serine 82 were evaluated in adolescent mice 48 h, 72 h, and 7 days after treatments in the left ventricle. NA and normetanephrine (NMN) were determined by high-performance liquid chromatography (HPLC); TH and HSP27 expression and phosphorylation were measured by quantitative blot immunollabeling using specific antibodies. Ethanol and MDMA co-administration increased NA turnover and TH expression and phosphorylation versus the consumption of each one of these drugs. In parallel with the described modifications in the cardiac sympathetic activity, our results showed that binge ethanol+MDMA exposure is associated with an increase in HSP27 expression and phosphorylation in the left ventricle, supporting the idea that the combination of both drugs exacerbates the cellular stress induced by ethanol or MDMA alone. PMID:26509576

  7. Binge Ethanol and MDMA Combination Exacerbates Toxic Cardiac Effects by Inducing Cellular Stress.

    PubMed

    Navarro-Zaragoza, Javier; Ros-Simó, Clara; Milanés, María-Victoria; Valverde, Olga; Laorden, María-Luisa

    2015-01-01

    Binge drinking is a common pattern of ethanol consumption among young people. Binge drinkers are especially susceptible to brain damage when other substances are co-administered, in particular 3,4 methylendioxymethamphetamine (MDMA). The aim of the present work was to study the mechanisms implicated in the adaptive changes observed after administration of these drugs of abuse. So, we have evaluated the cardiac sympathetic activity and the expression and activation of heat shock protein 27 (HSP27), after voluntary binge ethanol consumption, alone and in combination with MDMA. Both parameters are markers of stressful situations and they could be modified inducing several alterations in different systems. Adolescent mice received MDMA, ethanol or both (ethanol plus MDMA). Drinking in the dark (DID) procedure was used as a model of binge. Noradrenaline (NA) turnover, tyrosine hydroxylase (TH), TH phosphorylated at serine 31 and HSP27 expression and its phosphorylation at serine 82 were evaluated in adolescent mice 48 h, 72 h, and 7 days after treatments in the left ventricle. NA and normetanephrine (NMN) were determined by high-performance liquid chromatography (HPLC); TH and HSP27 expression and phosphorylation were measured by quantitative blot immunollabeling using specific antibodies. Ethanol and MDMA co-administration increased NA turnover and TH expression and phosphorylation versus the consumption of each one of these drugs. In parallel with the described modifications in the cardiac sympathetic activity, our results showed that binge ethanol+MDMA exposure is associated with an increase in HSP27 expression and phosphorylation in the left ventricle, supporting the idea that the combination of both drugs exacerbates the cellular stress induced by ethanol or MDMA alone.

  8. [Vitamins and oxidative stress].

    PubMed

    Kodentsova, V M; Vrzhesinskaia, O A; Mazo, V K

    2013-01-01

    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.

  9. Oxidative Stress in Atopic Dermatitis

    PubMed Central

    Ji, Hongxiu; Li, Xiao-Kang

    2016-01-01

    Atopic dermatitis (AD) is a chronic pruritic skin disorder affecting many people especially young children. It is a disease caused by the combination of genetic predisposition, immune dysregulation, and skin barrier defect. In recent years, emerging evidence suggests oxidative stress may play an important role in many skin diseases and skin aging, possibly including AD. In this review, we give an update on scientific progress linking oxidative stress to AD and discuss future treatment strategies for better disease control and improved quality of life for AD patients. PMID:27006746

  10. [Oxidative stress in Crohn's disease].

    PubMed

    Moret, Inés; Cerrillo, Elena; Navarro-Puche, Ana; Iborra, Marisa; Rausell, Francisco; Tortosa, Luis; Beltrán, Belén

    2014-01-01

    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.

  11. Peroxisomes, oxidative stress, and inflammation

    PubMed Central

    Terlecky, Stanley R; Terlecky, Laura J; Giordano, Courtney R

    2012-01-01

    Peroxisomes are intracellular organelles mediating a wide variety of biosynthetic and biodegradative reactions. Included among these are the metabolism of hydrogen peroxide and other reactive species, molecules whose levels help define the oxidative state of cells. Loss of oxidative equilibrium in cells of tissues and organs potentiates inflammatory responses which can ultimately trigger human disease. The goal of this article is to review evidence for connections between peroxisome function, oxidative stress, and inflammation in the context of human health and degenerative disease. Dysregulated points in this nexus are identified and potential remedial approaches are presented. PMID:22649571

  12. Oxidative stress in cyanobacteria.

    PubMed

    Latifi, Amel; Ruiz, Marion; Zhang, Cheng-Cai

    2009-03-01

    Reactive oxygen species (ROS) are byproducts of aerobic metabolism and potent agents that cause oxidative damage. In oxygenic photosynthetic organisms such as cyanobacteria, ROS are inevitably generated by photosynthetic electron transport, especially when the intensity of light-driven electron transport outpaces the rate of electron consumption during CO(2) fixation. Because cyanobacteria in their natural habitat are often exposed to changing external conditions, such as drastic fluctuations of light intensities, their ability to perceive ROS and to rapidly initiate antioxidant defences is crucial for their survival. This review summarizes recent findings and outlines important perspectives in this field.

  13. Oxidative stress in obstructive nephropathy.

    PubMed

    Dendooven, Amélie; Ishola, David A; Nguyen, Tri Q; Van der Giezen, Dionne M; Kok, Robbert Jan; Goldschmeding, Roel; Joles, Jaap A

    2011-06-01

    Unilateral ureteric obstruction (UUO) is one of the most commonly applied rodent models to study the pathophysiology of renal fibrosis. This model reflects important aspects of inflammation and fibrosis that are prominent in human kidney diseases. In this review, we present an overview of the factors contributing to the pathophysiology of UUO, highlighting the role of oxidative stress.

  14. Oxidative stress in obstructive nephropathy

    PubMed Central

    Dendooven, Amélie; Ishola, David A; Nguyen, Tri Q; Van der Giezen, Dionne M; Kok, Robbert Jan; Goldschmeding, Roel; Joles, Jaap A

    2011-01-01

    Unilateral ureteric obstruction (UUO) is one of the most commonly applied rodent models to study the pathophysiology of renal fibrosis. This model reflects important aspects of inflammation and fibrosis that are prominent in human kidney diseases. In this review, we present an overview of the factors contributing to the pathophysiology of UUO, highlighting the role of oxidative stress. PMID:20804541

  15. Oxidative Stress and Neurodegenerative Disorders

    PubMed Central

    Li, Jie; O, Wuliji; Li, Wei; Jiang, Zhi-Gang; Ghanbari, Hossein A.

    2013-01-01

    Living cells continually generate reactive oxygen species (ROS) through the respiratory chain during energetic metabolism. ROS at low or moderate concentration can play important physiological roles. However, an excessive amount of ROS under oxidative stress would be extremely deleterious. The central nervous system (CNS) is particularly vulnerable to oxidative stress due to its high oxygen consumption, weakly antioxidative systems and the terminal-differentiation characteristic of neurons. Thus, oxidative stress elicits various neurodegenerative diseases. In addition, chemotherapy could result in severe side effects on the CNS and peripheral nervous system (PNS) of cancer patients, and a growing body of evidence demonstrates the involvement of ROS in drug-induced neurotoxicities as well. Therefore, development of antioxidants as neuroprotective drugs is a potentially beneficial strategy for clinical therapy. In this review, we summarize the source, balance maintenance and physiologic functions of ROS, oxidative stress and its toxic mechanisms underlying a number of neurodegenerative diseases, and the possible involvement of ROS in chemotherapy-induced toxicity to the CNS and PNS. We ultimately assess the value for antioxidants as neuroprotective drugs and provide our comments on the unmet needs. PMID:24351827

  16. Space flight and oxidative stress

    NASA Technical Reports Server (NTRS)

    Stein, T. P.

    2002-01-01

    Space flight is associated with an increase in oxidative stress after return to 1g. The effect is more pronounced after long-duration space flight. The effects lasts for several weeks after landing. In humans there is increased lipid peroxidation in erythrocyte membranes, reduction in some blood antioxidants, and increased urinary excretion of 8-iso-prostaglandin F(2alpha) and 8-oxo-7,8 dihydro-2 deoxyguanosine. Isoprostane 8-iso-prostaglandin F(2alpha) and 8-oxo-7,8 dihydro-2 deoxyguanosine are markers for oxidative damage to lipids and DNA, respectively. The changes have been attributed to a combination of the energy deficiency that occurs during flight and substrate competition for amino acids occurring between repleting muscle and other tissues during the recovery phase. The observations in humans have been complemented by rodent studies. Most rodent studies showed increased production of lipid peroxidation products postflight and decreased antioxidant enzyme activity postflight. The rodent observations were attributed to the stress associated with reentry into Earth's gravity. Decreasing the imbalance between the production of endogenous oxidant defenses and oxidant production by increasing the supply of dietary antioxidants may lessen the severity of the postflight increase in oxidative stress.

  17. Estradiol and neurodegenerative oxidative stress.

    PubMed

    Nilsen, Jon

    2008-10-01

    Estradiol is a potent preventative against neurodegenerative disease, in part, by activating antioxidant defense systems scavenging reactive oxygen species, limiting mitochondrial protein damage, improving electron transport chain activity and reducing mitochondrial DNA damage. Estradiol also increases the activity of complex IV of the electron transport chain, improving mitochondrial respiration and ATP production under normal and stressful conditions. However, the high oxidative cellular environment present during neurodegeneration makes estradiol a poor agent for treatment of existing disease. Oxidative stress stimulates the production of the hydroperoxide-dependent hydroxylation of estradiol to the catecholestrogen metabolites, which can undergo reactive oxygen species producing redox cycling, setting up a self-generating toxic cascade offsetting any antioxidant/antiapoptotic effects generated by the parent estradiol. Additional disease-induced factors can further perpetuate this cycle. For example dysregulation of the catecholamine system could alter catechol-O-methyltransferase-catalyzed methylation, preventing removal of redox cycling catecholestrogens from the system enhancing pro-oxidant effects of estradiol.

  18. Causes and consequences of oxidative stress in spermatozoa.

    PubMed

    Aitken, Robert John; Gibb, Zamira; Baker, Mark A; Drevet, Joel; Gharagozloo, Parviz

    2016-01-01

    Spermatozoa are highly vulnerable to oxidative attack because they lack significant antioxidant protection due to the limited volume and restricted distribution of cytoplasmic space in which to house an appropriate armoury of defensive enzymes. In particular, sperm membrane lipids are susceptible to oxidative stress because they abound in significant amounts of polyunsaturated fatty acids. Susceptibility to oxidative attack is further exacerbated by the fact that these cells actively generate reactive oxygen species (ROS) in order to drive the increase in tyrosine phosphorylation associated with sperm capacitation. However, this positive role for ROS is reversed when spermatozoa are stressed. Under these conditions, they default to an intrinsic apoptotic pathway characterised by mitochondrial ROS generation, loss of mitochondrial membrane potential, caspase activation, phosphatidylserine exposure and oxidative DNA damage. In responding to oxidative stress, spermatozoa only possess the first enzyme in the base excision repair pathway, 8-oxoguanine DNA glycosylase. This enzyme catalyses the formation of abasic sites, thereby destabilising the DNA backbone and generating strand breaks. Because oxidative damage to sperm DNA is associated with both miscarriage and developmental abnormalities in the offspring, strategies for the amelioration of such stress, including the development of effective antioxidant formulations, are becoming increasingly urgent.

  19. Hemoglobin oxidative stress in cancer.

    PubMed

    Della Rovere, F; Granata, A; Broccio, M; Zirilli, A; Broccio, G

    1995-01-01

    The role played by free radicals in carcinogenesis and their relationships with antioxidant pool and cancer have already been shown. Free radicals induce increased membrane permeability through membrane lipid peroxidation, protein oxidation and histamine release from mast cells. Free radicals also cause oxyhemoglobin oxidative stress which increases methemoglobin and hemichromes. For this reason, we studied the in vitro formation of methemoglobin at 0' and 90', dosed following the HPLC method, after oxidative stress of blood by means of acetylphenylhydrazine in 40 subjects with cancer and 40 healthy donors. The results showed that methemoglobin formation was highly significant in tumors as compared to controls (P < 0.0001). The statistical analyses we carried out showed that metHb formation is not affected by age, sex, smoking habit, red blood cell number, Hb, Ht or tumor staging. This makes us believe that free radicals alter erythrocyte membrane permeability and predenaturate oxyhemoglobin so that erythrocyte membrane becomes more susceptible to new oxidative stress. This caused the abnormal response we found. Our results clearly underline the role played by free radicals in tumorous disease and provide a successful and easy method to detect early, even in a pre-clinical stage, the presence of tumorous alterations in the human body.

  20. Disturbance in the Mucosa-Associated Commensal Bacteria Is Associated with the Exacerbation of Chronic Colitis by Repeated Psychological Stress; Is That the New Target of Probiotics?

    PubMed Central

    Arase, Sohei; Watanabe, Yohei; Setoyama, Hiromi; Nagaoka, Noriko; Kawai, Mitsuhisa; Matsumoto, Satoshi

    2016-01-01

    Psychological stress can exacerbate inflammatory bowel disease. However, the mechanisms underlying how psychological stress affects gut inflammation remain unclear. Here, we focused on the relationship between changes in the microbial community of mucosa-associated commensal bacteria (MACB) and mucosal immune responses induced by chronic psychological stress in a murine model of ulcerative colitis. Furthermore, we examined the effect of probiotic treatment on exacerbated colitis and MACB composition changes induced by chronic psychological stress. Repeated water avoidance stress (rWAS) in B6-Tcra-/- mice severely exacerbated colitis, which was evaluated by both colorectal tissue weight and histological score of colitis. rWAS treatment increased mRNA expression of UCN2 and IFN-γ in large intestinal lamina propria mononuclear cells (LI-LPMC). Interestingly, exacerbated colitis was associated with changes in the microbial community of MACB, specifically loss of bacterial species diversity and an increase in the component ratio of Clostridium, revealed by 16S rRNA gene amplicon analysis. Finally, the oral administration of a probiotic Lactobacillus strain was protective against the exacerbation of colitis and was associated with a change in the bacterial community of MACB in rWAS-exposed Tcra-/- mice. Taken together, these results suggested that loss of species diversity in MACB might play a key role in exacerbated colitis induced by chronic psychological stress. In addition, probiotic treatment may be used as a tool to preserve the diversity of bacterial species in MACB and alleviate gut inflammation induced by psychological stress. PMID:27500935

  1. Neurodegenerative diseases and oxidative stress.

    PubMed

    Emerit, J; Edeas, M; Bricaire, F

    2004-01-01

    Oxidative stress is now recognized as accountable for redox regulation involving reactive oxygen species (ROS) and reactive nitrogen species (RNS). Its role is pivotal for the modulation of critical cellular functions, notably for neurons astrocytes and microglia, such as apoptosis program activation, and ion transport, calcium mobilization, involved in excitotoxicity. Excitotoxicity and apoptosis are the two main causes of neuronal death. The role of mitochondria in apoptosis is crucial. Multiple apoptotic pathways emanate from the mitochondria. The respiratory chain of mitochondria that by oxidative phosphorylation, is the fount of cellular energy, i.e. ATP synthesis, is responsible for most of ROS and notably the first produced, superoxide anion (O(2)(;-)). Mitochondrial dysfunction, i.e. cell energy impairment, apoptosis and overproduction of ROS, is a final common pathogenic mechanism in aging and in neurodegenerative disease such as Alzheimer's disease (AD), Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS). Nitric oxide (NO(;)), an RNS, which can be produced by three isoforms of NO-synthase in brain, plays a prominent role. The research on the genetics of inherited forms notably ALS, AD, PD, has improved our understanding of the pathobiology of the sporadic forms of neurodegenerative diseases or of aging of the brain. ROS and RNS, i.e. oxidative stress, are not the origin of neuronal death. The cascade of events that leads to neurons, death is complex. In addition to mitochondrial dysfunction (apoptosis), excitotoxicity, oxidative stress (inflammation), the mechanisms from gene to disease involve also protein misfolding leading to aggregates and proteasome dysfunction on ubiquinited material.

  2. Oxidative stress and glycemic regulation.

    PubMed

    Ceriello, A

    2000-02-01

    Oxidative stress is an acknowledged pathogenetic mechanism in diabetic complications. Hyperglycemia is a widely known cause of enhanced free radical concentration, whereas oxidative stress involvement in glycemic regulation is still debated. Glucose transport is a cascade of events starting from the interaction of insulin with its own receptor at the plasma membrane and ending with intracellular glucose metabolism. In this complex series of events, each step plays an important role and can be inhibited by a negative effect of oxidative stress. Several studies show that an acute increase in the blood glucose level may impair the physiological homeostasis of many systems in living organisms. The mechanisms through which acute hyperglycemia exerts these effects may be identified in the production of free radicals. It has been suggested that insulin resistance may be accompanied by intracellular production of free radicals. In adipocytes cultured in vitro, insulin increases the production of hydrogen peroxide, which has been shown to mimic the action of insulin. These data allow us to hypothesize that a vicious circle between hyperinsulinemia and free radicals could be operating: insulin resistance might cause elevated plasma free radical concentrations, which, in turn, might be responsible for a deterioration of insulin action, with hyperglycemia being a contributory factor. Data supporting this hypothesis are available. Vitamin E improves insulin action in healthy, elderly, and non-insulin-dependent diabetic subjects. Similar results can be obtained by vitamin C administration.

  3. [Oxidative stress and endothelial dysfunction].

    PubMed

    Jarasūniene, Dalia; Simaitis, Audrius

    2003-01-01

    Growing numbers of morbidity and mortality due to the Coronary Heart Disease (CHD) is recognized as the more increasing challenge in the world. The initial stage of atherosclerosis, early diagnosis and treatment of CHD are the main objectives of current research. Endothelium dysfunction, the earliest expression of the atherosclerotic process is associated with subtle biochemical changes that gradually are transformed into the structural changes of the arterial wall. The theory of free radicals is the most common among the atherosclerosis explanations. Overproduction or impaired neutralization of the free radicals accounts for oxidative stress that is causing substantial damage to the low density lipoproteins, nitric oxyde (NO), endothelium cells, tissue cells and finally leads to the endothelium dysfuction. Pathophysiology of oxidative stress and its role in the endothelium dysfunction are discussed in this paper. Positive role of various medications (statins, angiotensin converting enzym inhibitors, aldosteron antagonists, estrogens, antioxidants, b-blockers with vasodilatative properties) to the oxidative stress and consequently to the endothelium dysfuction are discussed as well.

  4. p53, Oxidative Stress, and Aging

    PubMed Central

    Liu, Dongping

    2011-01-01

    Abstract 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 prooxidative 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. Antioxid. Redox Signal. 15, 1669–1678. PMID:21050134

  5. Oxidative Stress and the Homeodynamics of Iron Metabolism

    PubMed Central

    Bresgen, Nikolaus; Eckl, Peter M.

    2015-01-01

    Iron and oxygen share a delicate partnership since both are indispensable for survival, but if the partnership becomes inadequate, this may rapidly terminate life. Virtually all cell components are directly or indirectly affected by cellular iron metabolism, which represents a complex, redox-based machinery that is controlled by, and essential to, metabolic requirements. Under conditions of increased oxidative stress—i.e., enhanced formation of reactive oxygen species (ROS)—however, this machinery may turn into a potential threat, the continued requirement for iron promoting adverse reactions such as the iron/H2O2-based formation of hydroxyl radicals, which exacerbate the initial pro-oxidant condition. This review will discuss the multifaceted homeodynamics of cellular iron management under normal conditions as well as in the context of oxidative stress. PMID:25970586

  6. Oxidative stress in androgenetic alopecia

    PubMed Central

    Prie, BE; Iosif, L; Tivig, I; Stoian, I; Giurcaneanu, C

    2016-01-01

    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 (p<0.01) SOD activity was found in patients with androgenetic alopecia. For plasma samples decreased TEAC activity (p<0.001), increased MDA levels (p<0.001) and no change in total thiols concentration were found in patients when compared with the controls. Discussions:Decreased total antioxidant activity and increased MDA levels found in plasma samples of patients with androgenetic alopecia 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. Abbreviations: AAG = androgenetic alopecia, MDA = malondialdehyde, SOD = superoxide dismutase

  7. Oxidative stress in androgenetic alopecia.

    PubMed

    Prie, B E; Iosif, L; Tivig, I; Stoian, I; Giurcaneanu, C

    2016-01-01

    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 (p<0.01) SOD activity was found in patients with androgenetic alopecia. For plasma samples decreased TEAC activity (p<0.001), increased MDA levels (p<0.001) and no change in total thiols concentration were found in patients when compared with the controls. Discussions:Decreased total antioxidant activity and increased MDA levels found in plasma samples of patients with androgenetic alopecia 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.

  8. Oxidative Stress in Inherited Mitochondrial Diseases

    PubMed Central

    Hayashi, Genki; Cortopassi, Gino

    2015-01-01

    Mitochondria are a source of reactive oxygen species (ROS). Mitochondrial diseases are the result of inherited defects in mitochondrially-expressed genes. One potential pathomechanism for mitochondrial disease is oxidative stress. Oxidative stress can occur as the result of increased ROS production, or decreased ROS protection. The role of oxidative stresses in the five most common inherited mitochondrial diseases; Friedreich's ataxia (FA), LHON, MELAS, MERRF and Leigh Syndrome (LS) is discussed. Published reports for oxidative stress involvement in pathomechanism in these five mitochondrial diseases are reviewed. The strongest for oxidative stress pathomechanism among the five diseases was in Friedreich's ataxia. In addition, a meta-analysis was carried out to provide an unbiased evaluation of the role of oxidative stress in the five diseases, by searching for oxidative stress citation count frequency within each disease. Of the five most common mitochondrial diseases, the strongest support for oxidative stress is in Friedreich's ataxia (6.42%), followed by LHON (2.45%), MELAS (2.18%), MERRF (1.71%), and LS (1.03%). The increased frequency of oxidative stress citations was significant relative to the mean of the total pool of five diseases (p<0.01) and the mean of the four non-Friedreich's diseases (p<0.0001). Thus there is support for oxidative stress in all five most common mitochondrial diseases, but the strongest, significant support is for Friedreich's ataxia. PMID:26073122

  9. Oxidative Stress in Oral Diseases

    PubMed Central

    Kesarwala, Aparna H.; Krishna, Murali C.; Mitchell, James B.

    2014-01-01

    Oxidative species, including reactive oxygen species (ROS), are components of normal cellular metabolism and are required for intracellular processes as varied as proliferation, signal transduction, and apoptosis. In the situation of chronic oxidative stress, however, ROS contribute to various pathophysiologies and are involved in multiple stages of carcinogenesis. In head and neck cancers specifically, many common risk factors contribute to carcinogenesis via ROS-based mechanisms, including tobacco, areca quid, alcohol, and viruses. Given their widespread influence on the process of carcinogenesis, ROS and their related pathways are attractive targets for intervention. The effects of radiation therapy, a central component of treatment for nearly all head and neck cancers, can also be altered via interfering with oxidative pathways. These pathways are also relevant to the development of many benign oral diseases. In this review, we outline how ROS contribute to pathophysiology with a focus toward head and neck cancers and benign oral diseases, describing potential targets and pathways for intervention that exploit the role of oxidative species in these pathologic processes. PMID:25417961

  10. Oxidative Stress and HPV Carcinogenesis

    PubMed Central

    De Marco, Federico

    2013-01-01

    Extensive experimental work has conclusively demonstrated that infection with certain types of human papillomaviruses, the so-called high-risk human papillomavirus (HR-HPV), represent a most powerful human carcinogen. However, neoplastic growth is a rare and inappropriate outcome in the natural history of HPV, and a number of other events have to concur in order to induce the viral infection into the (very rare) neoplastic transformation. From this perspective, a number of putative viral, host, and environmental co-factors have been proposed as potential candidates. Among them oxidative stress (OS) is an interesting candidate, yet comparatively underexplored. OS is a constant threat to aerobic organisms being generated during mitochondrial oxidative phosphorylation, as well as during inflammation, infections, ionizing irradiation, UV exposure, mechanical and chemical stresses. Epithelial tissues, the elective target for HPV infection, are heavily exposed to all named sources of OS. Two different types of cooperative mechanisms are presumed to occur between OS and HPV: I) The OS genotoxic activity and the HPV-induced genomic instability concur independently to the generation of the molecular damage necessary for the emergence of neoplastic clones. This first mode is merely a particular form of co-carcinogenesis; and II) OS specifically interacts with one or more molecular stages of neoplastic initiation and/or progression induced by the HPV infection. This manuscript was designed to summarize available data on this latter hypothesis. Experimental data and indirect evidences on promoting the activity of OS in viral infection and viral integration will be reviewed. The anti-apoptotic and pro-angiogenetic role of NO (nitric oxide) and iNOS (inducible nitric oxide synthase) will be discussed together with the OS/HPV cooperation in inducing cancer metabolism adaptation. Unexplored/underexplored aspects of the OS interplay with the HPV-driven carcinogenesis will be

  11. Oxidative Stress in Diabetic Nephropathy

    PubMed Central

    Kashihara, N.; Haruna, Y.; Kondeti, V.K.; Kanwar, Y.S.

    2013-01-01

    Diabetic nephropathy is a leading cause of end-stage renal failure worldwide. Its morphologic characteristics include glomerular hypertrophy, basement membrane thickening, mesangial expansion, tubular atrophy, interstitial fibrosis and arteriolar thickening. All of these are part and parcel of microvascular complications of diabetes. A large body of evidence indicates that oxidative stress is the common denominator link for the major pathways involved in the development and progression of diabetic micro- as well as macrovascular complications of diabetes. There are a number of macromolecules that have been implicated for increased generation of reactive oxygen species (ROS), such as, NAD(P)H oxidase, advanced glycation end products (AGE), defects in polyol pathway, uncoupled nitric oxide synthase (NOS) and mitochondrial respiratory chain via oxidative phosphorylation. Excess amounts of ROS modulate activation of protein kinase C, mitogen-activated protein kinases, and various cytokines and transcription factors which eventually cause increased expression of extracellular matrix (ECM) genes with progression to fibrosis and end stage renal disease. Activation of renin-angiotensin system (RAS) further worsens the renal injury induced by ROS in diabetic nephropathy. Buffering the generation of ROS may sound a promising therapeutic to ameliorate renal damage from diabetic nephropathy, however, various studies have demonstrated minimal reno-protection by these agents. Interruption in the RAS has yielded much better results in terms of reno-protection and progression of diabetic nephropathy. In this review various aspects of oxidative stress coupled with the damage induced by RAS are discussed with the anticipation to yield an impetus for designing new generation of specific antioxidants that are potentially more effective to reduce reno-vascular complications of diabetes. PMID:20939814

  12. Etiologies of sperm oxidative stress

    PubMed Central

    Sabeti, Parvin; Pourmasumi, Soheila; Rahiminia, Tahereh; Akyash, Fatemeh; Talebi, Ali Reza

    2016-01-01

    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. PMID:27351024

  13. Inflammation, oxidative stress, and obesity.

    PubMed

    Fernández-Sánchez, Alba; Madrigal-Santillán, Eduardo; Bautista, Mirandeli; Esquivel-Soto, Jaime; Morales-González, Angel; Esquivel-Chirino, Cesar; Durante-Montiel, Irene; Sánchez-Rivera, Graciela; Valadez-Vega, Carmen; Morales-González, José A

    2011-01-01

    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.

  14. Inflammation, Oxidative Stress, and Obesity

    PubMed Central

    Fernández-Sánchez, Alba; Madrigal-Santillán, Eduardo; Bautista, Mirandeli; Esquivel-Soto, Jaime; Morales-González, Ángel; Esquivel-Chirino, Cesar; Durante-Montiel, Irene; Sánchez-Rivera, Graciela; Valadez-Vega, Carmen; Morales-González, José A.

    2011-01-01

    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. PMID:21686173

  15. Oxidative stress in neonatology: a review.

    PubMed

    Mutinati, M; Pantaleo, M; Roncetti, M; Piccinno, M; Rizzo, A; Sciorsci, R L

    2014-02-01

    Free radicals are highly reactive oxidizing agents containing one or more unpaired electrons. Both in human and veterinary neonathology, it is generally accepted that oxidative stress functions as an important catalysator of neonatal disease. Soon after birth, many sudden physiological and environmental conditions make the newborn vulnerable for the negative effects of oxidative stress, which potentially can impair neonatal vitality. As a clinician, it is important to have in depth knowledge about factors affecting maternal/neonatal oxidative status and the cascades of events that enrol when the neonate is subjected to oxidative stress. This report aims at providing clinicians with an up-to-date review about oxidative stress in neonates across animal species. It will be emphasized which handlings and treatments that are applied during neonatal care or resuscitation can actually impose oxidative stress upon the neonate. Views and opinions about maternal and/or neonatal antioxydative therapy will be shared.

  16. Impact of oxidative stress in fetal programming.

    PubMed

    Thompson, Loren P; Al-Hasan, Yazan

    2012-01-01

    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 protect against organ dysfunction in the programmed offspring.

  17. Kinins— The Kallikrein-Kinin System and Oxidative Stress

    PubMed Central

    Kayashima, Yukako; Smithies, Oliver; Kakoki, Masao

    2012-01-01

    Purpose of review The Kallikrein-kinin system (KKS) constitutes a complex multi-enzyme cascade that produces several bioactive kinin peptides and their derivatives including bradykinin. In addition to the classical notion of the KKS as a potent vasodilator and a mediator of inflammatory responses, recent studies suggest a link between the KKS and oxidative stress. A number of established mouse model with altered levels of KKS components opened the way to evaluate precise functions of the KKS. Here we review recent findings on the role of the KKS in cardiovascular diseases and chronic kidney diseases, and discuss potential benefits of KKS activation in these diseases. Recent findings Deletion of both B1R and B2R in a diabetic mouse model exacerbates its renal phenotypes, suggesting that the KKS exerts protective effects on diabetic nephropathy by suppressing oxidative stress, presumably via nitric oxide (NO) and prostaglandins (PGs). Summary Accumulating evidence has highlighted the importance of the KKS as a protective system against oxidative stress and organ damage in the heart and kidney. The activation of the KKS by ACE inhibitors and vasopeptidase inhibitors is likely to be beneficial in senescence-associated cardiovascular diseases and chronic kidney diseases. PMID:22048723

  18. Oxidative stress and antioxidant defense mechanisms linked to exercise during cardiopulmonary and metabolic disorders.

    PubMed

    Fisher-Wellman, Kelsey; Bell, Heather K; Bloomer, Richard J

    2009-01-01

    Oxidative stress has been implicated in the pathophysiology of multiple human diseases, in addition to the aging process. Although various stimuli exist, acute exercise is known to induce a transient increase in reactive oxygen and nitrogen species (RONS), evident by several reports of increased oxidative damage following acute bouts of aerobic and anaerobic exercise. Although the results are somewhat mixed and appear disease dependent, individuals with chronic disease experience an exacerbation in oxidative stress following acute exercise when compared to healthy individuals. However, this increased oxidant stress may serve as a necessary "signal" for the upregulation in antioxidant defenses, thereby providing protection against subsequent exposure to prooxidant environments within susceptible individuals. Here we present studies related to both acute exercise-induced oxidative stress in those with disease, in addition to studies focused on adaptations resulting from increased RONS exposure associated with chronic exercise training in persons with disease.

  19. Do the serum oxidative stress biomarkers provide a reasonable index of the general oxidative stress status?

    PubMed

    Argüelles, Sandro; García, Sonia; Maldonado, Mariam; Machado, Alberto; Ayala, Antonio

    2004-11-01

    The oxidant status of an individual is assessed by determining a group of markers in noninvasive samples. One limitation when measuring these biomarkers is that they do not give information about tissue localization of oxidative stress. The present study was undertaken to establish whether the serum oxidative stress biomarkers are indicative of oxidative stress in tissues of an individual. To accomplish this, we determined a few generic markers of oxidation in serum and tissues of six groups of rats treated experimentally, to modulate their oxidative stress status. The correlation between serum and tissue levels was calculated for each marker. Also, for each tissue, the correlation between the values of these oxidative stress biomarkers was analysed. Our results show that only lipid peroxides in serum could be useful to predict the oxidative stress in tissues. No correlation was found between any of the oxidative stress markers in serum.

  20. Intracerebral Hemorrhage, Oxidative Stress, and Antioxidant Therapy

    PubMed Central

    Duan, Xiaochun; Wen, Zunjia; Shen, Haitao; Shen, Meifen

    2016-01-01

    Hemorrhagic stroke is a common and severe neurological disorder and is associated with high rates of mortality and morbidity, especially for intracerebral hemorrhage (ICH). Increasing evidence demonstrates that oxidative stress responses participate in the pathophysiological processes of secondary brain injury (SBI) following ICH. The mechanisms involved in interoperable systems include endoplasmic reticulum (ER) stress, neuronal apoptosis and necrosis, inflammation, and autophagy. In this review, we summarized some promising advances in the field of oxidative stress and ICH, including contained animal and human investigations. We also discussed the role of oxidative stress, systemic oxidative stress responses, and some research of potential therapeutic options aimed at reducing oxidative stress to protect the neuronal function after ICH, focusing on the challenges of translation between preclinical and clinical studies, and potential post-ICH antioxidative therapeutic approaches. PMID:27190572

  1. Intracerebral Hemorrhage, Oxidative Stress, and Antioxidant Therapy.

    PubMed

    Duan, Xiaochun; Wen, Zunjia; Shen, Haitao; Shen, Meifen; Chen, Gang

    2016-01-01

    Hemorrhagic stroke is a common and severe neurological disorder and is associated with high rates of mortality and morbidity, especially for intracerebral hemorrhage (ICH). Increasing evidence demonstrates that oxidative stress responses participate in the pathophysiological processes of secondary brain injury (SBI) following ICH. The mechanisms involved in interoperable systems include endoplasmic reticulum (ER) stress, neuronal apoptosis and necrosis, inflammation, and autophagy. In this review, we summarized some promising advances in the field of oxidative stress and ICH, including contained animal and human investigations. We also discussed the role of oxidative stress, systemic oxidative stress responses, and some research of potential therapeutic options aimed at reducing oxidative stress to protect the neuronal function after ICH, focusing on the challenges of translation between preclinical and clinical studies, and potential post-ICH antioxidative therapeutic approaches.

  2. Husbandry stress exacerbates mycobacterial infections in adult zebrafish, Danio rerio (Hamilton)

    USGS Publications Warehouse

    Ramsay, J.M.; Watral, V.; Schreck, C.B.; Kent, M.L.

    2009-01-01

    Mycobacteria are significant pathogens of laboratory zebrafish, Danio rerio (Hamilton). Stress is often implicated in clinical disease and morbidity associated with mycobacterial infections but has yet to be examined with zebrafish. The aim of this study was to examine the effects of husbandry stressors on zebrafish infected with mycobacteria. Adult zebrafish were exposed to Mycobacterium marinum or Mycobacterium chelonae, two species that have been associated with disease in zebrafish. Infected fish and controls were then subjected to chronic crowding and handling stressors and examined over an 8-week period. Whole-body cortisol was significantly elevated in stressed fish compared to non-stressed fish. Fish infected with M. marinum ATCC 927 and subjected to husbandry stressors had 14% cumulative mortality while no mortality occurred among infected fish not subjected to husbandry stressors. Stressed fish, infected with M. chelonae H1E2 from zebrafish, were 15-fold more likely to be infected than non-stressed fish at week 8 post-injection. Sub-acute, diffuse infections were more common among stressed fish infected with M. marinum or M. chelonae than non-stressed fish. This is the first study to demonstrate an effect of stress and elevated cortisol on the morbidity, prevalence, clinical disease and histological presentation associated with mycobacterial infections in zebrafish. Minimizing husbandry stress may be effective at reducing the severity of outbreaks of clinical mycobacteriosis in zebrafish facilities. ?? 2009 Blackwell Publishing Ltd.

  3. Oxidative Stress and Pulmonary Fibrosis

    PubMed Central

    Cheresh, Paul; Kim, Seok-Jo; Tulasiram, Sandhya; Kamp, David W.

    2012-01-01

    Oxidative stress is implicated as an important molecular mechanism underlying fibrosis in a variety of organs, including the lungs. However, the causal role of reactive oxygen species (ROS) released from environmental exposures and inflammatory / interstitial cells in mediating fibrosis as well as how best to target an imbalance in ROS production in patients with fibrosis are not firmly established. We focus on the role of ROS in pulmonary fibrosis and, where possible, highlight overlapping molecular pathways in other organs. The key origins of oxidative stress in pulmonary fibrosis (e.g. environmental toxins, mitochondria / NADPH oxidase of inflammatory and lung target cells, and depletion of antioxidant defenses) are reviewed. The role of alveolar epithelial cell (AEC) apoptosis by mitochondria- and p53-regulated death pathways are examined. We emphasize an emerging role for the endoplasmic reticulum (ER) in pulmonary fibrosis. After briefly summarizing how ROS trigger a DNA damage response, we concentrate on recent studies implicating a role for mitochondrial DNA (mtDNA) damage and repair mechanisms focusing on 8-oxoguanine DNA glycosylase (Ogg1) as well as crosstalk between ROS production, mtDNA damage, p53, Ogg1, and mitochondrial aconitase (ACO2). Finally, the association between ROS and TGF-β1-induced fibrosis is discussed. Novel insights into the molecular basis of ROS-induced pulmonary diseases and, in particular, lung epithelial cell death may promote the development of unique therapeutic targets for managing pulmonary fibrosis as well as fibrosis in other organs and tumors, and in aging; diseases for which effective management is lacking. PMID:23219955

  4. Oxidative Stress Adaptation with Acute, Chronic and Repeated Stress

    PubMed Central

    Pickering, Andrew M.; Vojtovich, Lesya; Tower, John; Davies, Kelvin J. A.

    2013-01-01

    Oxidative stress adaptation or hormesis is an important mechanism by which cells and organisms respond to, and cope with, environmental and physiological shifts in the level of oxidative stress. Most studies of oxidative stress adaption have been limited to adaptation induced by acute stress. In contrast, many if not most environmental and physiological stresses are either repeated or chronic. In this study we find that both cultured mammalian cells, and the fruit fly Drosophila melanogaster, are capable of adapting to chronic or repeated stress by up-regulating protective systems, such as their proteasomal proteolytic capacity to remove oxidized proteins. Repeated stress adaptation resulted in significant extension of adaptive responses. Repeated stresses must occur at sufficiently long intervals, however (12 hours or more for MEF cells and 7 days or more for flies), for adaptation to be successful, and the level of both repeated and chronic stress must be lower than is optimal for adaptation to acute stress. Regrettably, regimens of adaptation to both repeated and chronic stress that were successful for short-term survival in Drosophila, nevertheless also caused significant reductions in lifespan for the flies. Thus, although both repeated and chronic stress can be tolerated, they may result in a shorter life. PMID:23142766

  5. Cognitive and neuroinflammatory consequences of mild repeated stress are exacerbated in aged mice

    PubMed Central

    Buchanan, J.B.; Sparkman, N.L.; Chen, J.; Johnson, R.W.

    2008-01-01

    Summary Peripheral immune stimulation as well as certain types of psychological stress increases brain levels of inflammatory cytokines such as interleukin-1β (IL-1β), IL-6 and tumor necrosis factor α (TNFα). We have demonstrated that aged mice show greater increases in central inflammatory cytokines, as well as greater cognitive deficits, compared to adults in response to peripheral lipopolysaccharide (LPS) administration. Because aged mice are typically more sensitive to systemic stressors such as LPS, and certain psychological stressors induce physiological responses similar to those that follow LPS, we hypothesized that aged mice would be more sensitive to the physiological and cognitive effects of mild stress than adult mice. Here, adult (3–5 mo) and aged (22–23 mo) male BALB/c mice were trained in the Morris water maze for 5 days. Mice were then exposed to a mild restraint stress of 30 minutes before being tested in a working memory version of the water maze over a 3 day period. On day 4 mice were stressed and then killed for collection of blood and brain. In a separate group of animals, mice were killed immediately after one, two or three 30 min restraint sessions and blood for peripheral corticosterone and cytokine protein measurement, and brains were dissected for central cytokine mRNA measurement. Stress disrupted spatial working memory in both adult and aged mice but to a much greater extent in the aged mice. In addition, aged mice showed an increase in stress-induced expression of hippocampal IL-1β mRNA and MHC class II protein compared to non-stressed controls while expression in adult mice was unaffected by stress. These data show that aged mice are more sensitive to both the cognitive and inflammatory effects of mild stress than are adult mice and suggest a possible a role for IL-1β. PMID:18407425

  6. Induction of Oxidative Stress in Kidney

    PubMed Central

    Ozbek, Emin

    2012-01-01

    Oxidative stress has a critical role in the pathophysiology of several kidney diseases, and many complications of these diseases are mediated by oxidative stress, oxidative stress-related mediators, and inflammation. Several systemic diseases such as hypertension, diabetes mellitus, and hypercholesterolemia; infection; antibiotics, chemotherapeutics, and radiocontrast agents; and environmental toxins, occupational chemicals, radiation, smoking, as well as alcohol consumption induce oxidative stress in kidney. We searched the literature using PubMed, MEDLINE, and Google scholar with “oxidative stress, reactive oxygen species, oxygen free radicals, kidney, renal injury, nephropathy, nephrotoxicity, and induction”. The literature search included only articles written in English language. Letters or case reports were excluded. Scientific relevance, for clinical studies target populations, and study design, for basic science studies full coverage of main topics, are eligibility criteria for articles used in this paper. PMID:22577546

  7. Water stress exacerbates the severity of Botryosphaeria dieback in grapevines infected by Neofusicoccum parvum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Botryosphaeria dieback (causal fungus Neofusicoccum parvum) is a detrimental grapevine trunk disease, causing internal wood degradation, killing shoots, and reducing yields. We examined the interactive effects of drought and N. parvum infection, common vineyard stresses, on wood-lesion development. ...

  8. Clinical Relevance of Biomarkers of Oxidative Stress

    PubMed Central

    Frijhoff, Jeroen; Winyard, Paul G.; Zarkovic, Neven; Davies, Sean S.; Stocker, Roland; Cheng, David; Knight, Annie R.; Taylor, Emma Louise; Oettrich, Jeannette; Ruskovska, Tatjana; Gasparovic, Ana Cipak; Cuadrado, Antonio; Weber, Daniela; Poulsen, Henrik Enghusen; Grune, Tilman; Schmidt, Harald H.H.W.

    2015-01-01

    Abstract 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 using nonspecific methods, while specific methodologies are often too sophisticated or laborious for routine clinical use. Future Directions: Several markers of oxidative stress still represent a viable biomarker opportunity for clinical use. However, positive findings with currently used biomarkers still need to be validated in larger sample sizes and compared with current clinical standards to establish them as clinical diagnostics. It is important to realize that oxidative stress is a nuanced phenomenon that is difficult to characterize, and one biomarker is not necessarily better than others. The vast diversity in oxidative stress between diseases and conditions has to be taken into account when selecting the most appropriate biomarker. Antioxid. Redox Signal. 23, 1144–1170. PMID:26415143

  9. Oxidative stress in the neonate.

    PubMed

    Robles, R; Palomino, N; Robles, A

    2001-11-01

    The aim of this study is to determine the oxidative state of term and preterm neonates at the moment of birth and during the first days of life, and the influence of exposure to oxygen on the premature neonates.A total of 20 neonates were selected. Group A: 10 healthy full-term neonates, and Group B: 10 preterm neonates with no other pathology associated, requiring oxygen therapy. Venous samples were taken in cord at 3 and 72 h in Group A, and in cord at 3, 24 and 72 h and 7 days in Group B.Hydroperoxides, Q10 coenzyme (Co Q10) and alpha-tocopherol were measured within the erythrocyte membrane. Levels of hydroperoxides present in erythrocyte membrane were higher than normal both in Group A and in Group B at birth. This increase was greater in the group of premature neonates. Levels of alpha-tocopherol at birth increase significantly at 72 h in term neonates. Among the premature newborns, alpha-tocopherol levels are two to three times lower at birth and do not rise to higher levels as in the term neonate group. Fall in levels of Co Q10 in erythrocyte membranes is observed, and perhaps is due to the role of Co Q10 in maintaining the pool of reduced tocopherol. At birth, the neonate presents an increase of markers of oxidative stress and a decrease of their antioxidant defenses. This difference is greater as gestational age decreases. The application of oxygen therapy resulted in these levels which remain low throughout the study period.

  10. Global climate change and toxicology: Exacerbation of toxicity of pollutants by thermal stress

    EPA Science Inventory

    Relatively small elevations in the average global temperature can translate to greater incidences of heat alerts during the summer months, an effect that is especially prevalent in urban areas where simultaneous exposure to heat stress and excessive levels of air pollutants is co...

  11. PARTICULATE MATTER, OXIDATIVE STRESS AND ...

    EPA Pesticide Factsheets

    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

  12. Oxidative Stress Related Diseases in Newborns

    PubMed Central

    Aykac, Kubra

    2016-01-01

    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. PMID:27403229

  13. Ageing, oxidative stress, and mitochondrial uncoupling.

    PubMed

    Harper, M-E; Bevilacqua, L; Hagopian, K; Weindruch, R; Ramsey, J J

    2004-12-01

    Mitochondria are a cell's single greatest source of reactive oxygen species. Reactive oxygen species are important for many life sustaining processes of cells and tissues, but they can also induce cell damage and death. If their production and levels within cells is not effectively controlled, then the detrimental effects of oxidative stress can accumulate. Oxidative stress is widely thought to underpin many ageing processes, and the oxidative stress theory of ageing is one of the most widely acknowledged theories of ageing. As well as being the major source of reactive oxygen species, mitochondria are also a major site of oxidative damage. The purpose of this review is a concise and current review of the effects of oxidative stress and ageing on mitochondrial function. Emphasis is placed upon the roles of mitochondrial proton leak, the uncoupling proteins, and the anti-ageing effects of caloric restriction.

  14. Oxidative stress and oxidative damage in chemical carcinogenesis

    SciTech Connect

    Klaunig, James E. Wang Zemin; Pu Xinzhu; Zhou Shaoyu

    2011-07-15

    Reactive oxygen species (ROS) are induced through a variety of endogenous and exogenous sources. Overwhelming of antioxidant and DNA repair mechanisms in the cell by ROS may result in oxidative stress and oxidative damage to the cell. This resulting oxidative stress can damage critical cellular macromolecules and/or modulate gene expression pathways. Cancer induction by chemical and physical agents involves a multi-step process. This process includes multiple molecular and cellular events to transform a normal cell to a malignant neoplastic cell. Oxidative damage resulting from ROS generation can participate in all stages of the cancer process. An association of ROS generation and human cancer induction has been shown. It appears that oxidative stress may both cause as well as modify the cancer process. Recently association between polymorphisms in oxidative DNA repair genes and antioxidant genes (single nucleotide polymorphisms) and human cancer susceptibility has been shown.

  15. Nur77 exacerbates PC12 cellular injury in vitro by aggravating mitochondrial impairment and endoplasmic reticulum stress

    PubMed Central

    Gao, Huimin; Chen, Zhaoyu; Fu, Yongmei; Yang, Xiaoyan; Weng, Ruihui; Wang, Rui; Lu, Jianjun; Pan, Mengqiu; Jin, Kunlin; McElroy, Chris; Tang, Beisha; Xia, Ying; Wang, Qing

    2016-01-01

    The nuclear orphan receptor, Nur77 plays important roles in neuroimflammation, apoptosis, and dopaminergic neurodegeneration. We conducted a further mechanistic investigation into the association of Nur77 with cell death. Cytosporone B (Csn-B), an agonist for Nur77, and Nur77 knockdown were adopted in the 6-hydroxydopamine (OHDA)-lesioned PC12 cells to investigate the mechanisms underlying Nur77-mediated injury. The 6-OHDA incubation caused Nur77 translocation from the nucleus to cytosol and Endoplasm reticulum (ER) and induced co-localization of Tom20/Nur77 and Protein Disulfide Isomerase (PDI)/Nur77. Nur77 activation further decreased cell viability, aggravated intracellular LDH release, intracellular Ca2+, ROS levels, apoptosis, ER tress and, mitochondrial transmembrane potential (ΔΨm) decline. In addition, Nur77 activation significantly enhanced the efficiency of autophagy as indicated by an up-regulation of Beclin-1/LC-3 and downregulation of p62, and aggravated mitochondrial dysfunctions and ER stress as shown by increased HSP60/Cytochrome C (Cyt C) and CHOP-ATF3 levels respectively. These changes could be partially reversed by Nur77 knockdown. Moreover, Nur77 activation upregulated PINK1 and downregulated Parkin levels. We conclude that Nur77 exacerbates PC12 cell death at least partially by aggravating the mitochondrial impairment and ER stress and enhancing autophagy. We propose that Nur77 is likely a critical target in the PD therapy. PMID:27679973

  16. Relationships between Stress Granules, Oxidative Stress, and Neurodegenerative Diseases

    PubMed Central

    2017-01-01

    Cytoplasmic stress granules (SGs) are critical for facilitating stress responses and for preventing the accumulation of misfolded proteins. SGs, however, have been linked to the pathogenesis of neurodegenerative diseases, in part because SGs share many components with neuronal granules. Oxidative stress is one of the conditions that induce SG formation. SGs regulate redox levels, and SG formation in turn is differently regulated by various types of oxidative stress. These associations and other evidences suggest that SG formation contributes to the development of neurodegenerative diseases. In this paper, we review the regulation of SG formation/assembly and discuss the interactions between oxidative stress and SG formation. We then discuss the links between SGs and neurodegenerative diseases and the current therapeutic approaches for neurodegenerative diseases that target SGs. PMID:28194255

  17. Fipronil insecticide toxicology: oxidative stress and metabolism.

    PubMed

    Wang, Xu; Martínez, María Aránzazu; Wu, Qinghua; Ares, Irma; Martínez-Larrañaga, María Rosa; Anadón, Arturo; Yuan, Zonghui

    2016-11-01

    Fipronil (FIP) is widely used across the world as a broad-spectrum phenylpyrazole insecticide and veterinary drug. FIP was the insecticide to act by targeting the γ-aminobutyric acid (GABA) receptor and has favorable selective toxicity towards insects rather than mammals. However, because of accidental exposure, incorrect use of FIP or widespread FIP use leading to the contamination of water and soil, there is increasing evidence that FIP could cause a variety of toxic effects on animals and humans, such as neurotoxic, hepatotoxic, nephrotoxic, reproductive, and cytotoxic effects on vertebrate and invertebrates. In the last decade, oxidative stress has been suggested to be involved in the various toxicities induced by FIP. To date, few reviews have addressed the toxicity of FIP in relation to oxidative stress. The focus of this article is primarily intended to summarize the progress in research associated with oxidative stress as a possible mechanism for FIP-induced toxicity as well as metabolism. The present review reports that studies have been conducted to reveal the generation of reactive oxygen species (ROS) and oxidative stress as a result of FIP treatment and have correlated them with various types of toxicity. Furthermore, the metabolism of FIP was also reviewed, and during this process, various CYP450 enzymes were involved and oxidative stress might occur. The roles of various compounds in protecting against FIP-induced toxicity based on their anti-oxidative effects were also summarized to further understand the role of oxidative stress in FIP-induced toxicity.

  18. Oxidative stress and the ageing endocrine system.

    PubMed

    Vitale, Giovanni; Salvioli, Stefano; Franceschi, Claudio

    2013-04-01

    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.

  19. Proteomics, oxidative stress and male infertility.

    PubMed

    Agarwal, Ashok; Durairajanayagam, Damayanthi; Halabi, Jacques; Peng, Jason; Vazquez-Levin, Monica

    2014-07-01

    Oxidative stress has been established as one of the main causes of male infertility and has been implicated in many diseases associated with infertile men. It results from high concentrations of free radicals and suppressed antioxidant potential, which may alter protein expression in seminal plasma and/or spermatozoa. In recent years, proteomic analyses have been performed to characterize the protein profiles of seminal ejaculate from men with different clinical conditions, such as high oxidative stress. The aim of the present review is to summarize current findings on proteomic studies performed in men with high oxidative stress compared with those with physiological concentrations of free radicals, to better understand the aetiology of oxidative stress-induced male infertility. Each of these studies has suggested candidate biomarkers of oxidative stress, among them are DJ-1, PIP, lactotransferrin and peroxiredoxin. Changes in protein concentrations in seminal plasma samples with oxidative stress conditions were related to stress responses and to regulatory pathways, while alterations in sperm proteins were mostly associated to metabolic responses (carbohydrate metabolism) and stress responses. Future studies should include assessment of post-translational modifications in the spermatozoa as well as in seminal plasma proteomes of men diagnosed with idiopathic infertility. Oxidative stress, which occurs due to a state of imbalance between free radicals and antioxidants, has been implicated in most cases of male infertility. Cells that are in a state of oxidative stress are more likely to have altered protein expression. The aim of this review is to better understand the causes of oxidative stress-induced male infertility. To achieve this, we assessed proteomic studies performed on the seminal plasma and spermatozoa of men with high levels of oxidative stress due to various clinical conditions and compared them with men who had physiological concentrations of free

  20. Heat stress does not exacerbate tennis-induced alterations in physical performance

    PubMed Central

    Girard, Olivier; Christian, Ryan J; Racinais, Sébastien; Périard, Julien D

    2014-01-01

    Objectives To assess the time course of changes in physical performance in response to match-play tennis under heat stress. Methods Two matches consisting of 20 min of effective playing time (2×10 min segments) were played in COOL (∼102 min; ∼22°C and 70% relative humidity (RH)) and HOT (∼119 min; ∼36°C and 35% RH) environments. Repeated-sprint ability (3×15 m, 15 s rest), 15 m sprint time with a direction change (180°), vertical jump height (squat and countermovement jumps) and leg stiffness (multirebound jumps) were assessed in 12 competitive male players prematch, midmatch and postmatch, and 24 and 48 h after match completion. Results During the repeated-sprint ability test, initial (+2.3% and +3.1%) and cumulated sprint (+1.5% and +2.8%) times increased from prematch to midmatch and postmatch, respectively (p<0.001), while the sprint decrement score did not change. Match-play tennis induced a slowing (average of both conditions: +1.1% and +1.3% at midmatch and postmatch time points; p=0.05) of 15 m sprint time with direction change. Compared with prematch, leg stiffness (−6.4% and −6.5%; p<0.001) and squat jump height (−1.5% and −2.4%; p=0.05), but not countermovement jump height (−0.7% and −1.3%; p>0.05), decreased midmatch and postmatch, respectively, regardless of the condition. Complete recovery in all physical performance markers occurred within 24 h. Conclusions In tennis, match-related fatigue is characterised by impaired repeated-sprint ability, explosive power and leg stiffness at midmatch and postmatch, with values restored to prematch baseline 24 h into recovery. In addition, physical performance responses (match and recovery kinetics) are identical when competing in cool and hot environments. PMID:24668378

  1. Oxidative Stress, Prooxidants, and Antioxidants: The Interplay

    PubMed Central

    Rahal, Anu; Kumar, Amit; Singh, Vivek; Yadav, Brijesh

    2014-01-01

    Oxidative stress is a normal phenomenon in the body. Under normal conditions, the physiologically important intracellular levels of reactive oxygen species (ROS) are maintained at low levels by various enzyme systems participating in the in vivo redox homeostasis. Therefore, oxidative stress can also be viewed as an imbalance between the prooxidants and antioxidants in the body. For the last two decades, oxidative stress has been one of the most burning topics among the biological researchers all over the world. Several reasons can be assigned to justify its importance: knowledge about reactive oxygen and nitrogen species production and metabolism; identification of biomarkers for oxidative damage; evidence relating manifestation of chronic and some acute health problems to oxidative stress; identification of various dietary antioxidants present in plant foods as bioactive molecules; and so on. This review discusses the importance of oxidative stress in the body growth and development as well as proteomic and genomic evidences of its relationship with disease development, incidence of malignancies and autoimmune disorders, increased susceptibility to bacterial, viral, and parasitic diseases, and an interplay with prooxidants and antioxidants for maintaining a sound health, which would be helpful in enhancing the knowledge of any biochemist, pathophysiologist, or medical personnel regarding this important issue. PMID:24587990

  2. Oxidative Stress in Aging Human Skin

    PubMed Central

    Rinnerthaler, Mark; Bischof, Johannes; Streubel, Maria Karolin; Trost, Andrea; Richter, Klaus

    2015-01-01

    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

  3. Oxidative Stress in Placenta: Health and Diseases

    PubMed Central

    Wu, Fan; Tian, Fu-Ju; Lin, Yi

    2015-01-01

    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. PMID:26693479

  4. Mammalian Metallothionein-2A and Oxidative Stress

    PubMed Central

    Ling, Xue-Bin; Wei, Hong-Wei; Wang, Jun; Kong, Yue-Qiong; Wu, Yu-You; Guo, Jun-Li; Li, Tian-Fa; Li, Ji-Ke

    2016-01-01

    Mammalian metallothionein-2A (MT2A) has received considerable attention in recent years due to its crucial pathophysiological role in anti-oxidant, anti-apoptosis, detoxification and anti-inflammation. For many years, most studies evaluating the effects of MT2A have focused on reactive oxygen species (ROS), as second messengers that lead to oxidative stress injury of cells and tissues. Recent studies have highlighted that oxidative stress could activate mitogen-activated protein kinases (MAPKs), and MT2A, as a mediator of MAPKs, to regulate the pathogenesis of various diseases. However, the molecule mechanism of MT2A remains elusive. A deeper understanding of the functional, biochemical and molecular characteristics of MT2A would be identified, in order to bring new opportunities for oxidative stress therapy. PMID:27608012

  5. Oxidative and nitrosative stress in trichloroethene-mediated autoimmune response.

    PubMed

    Wang, Gangduo; Cai, Ping; Ansari, G A S; Khan, M Firoze

    2007-01-18

    Reactive oxygen and nitrogen species (RONS) are implicated in the pathogenesis of several autoimmune diseases. Also, increased lipid peroxidation and protein nitration are reported in systemic autoimmune diseases. Lipid peroxidation-derived aldehydes (LPDAs) such as malondialdehyde (MDA) and 4-hydroxynonenal (HNE) are highly reactive and bind proteins covalently, but their potential to elicit an autoimmune response and contribution to disease pathogenesis remain unclear. Similarly, nitration of protein could also contribute to disease pathogenesis. To assess the status of lipid peroxidation and/or RONS, autoimmune-prone female MRL+/+ mice (5-week old) were treated with trichloroethene (TCE), an environmental contaminant known to induce autoimmune response, for 48 weeks (0.5mg/ml via drinking water), and formation of antibodies to LPDA-protein adducts was followed in the sera of control and TCE-treated mice. TCE treatment led to greater formation of both anti-MDA- and -HNE-protein adduct antibodies and higher serum iNOS and nitrotyrosine levels. The increase in TCE-induced oxidative stress was associated with increases in anti-nuclear-, anti-ssDNA- and anti-dsDNA-antibodies. These findings suggest that TCE exposure not only leads to oxidative/nitrosative stress, but is also associated with induction/exacerbation of autoimmune response in MRL+/+ mice. Further interventional studies are needed to establish a causal role of RONS in TCE-mediated autoimmunity.

  6. Oxidative stress in IgA nephropathy.

    PubMed

    Coppo, R; Camilla, R; Amore, A; Peruzzi, L

    2010-01-01

    IgA nephropathy (IgAN) is characterized by mesangial deposits of IgA1, likely due to accumulation of IgA immune complexes. The activation of intracellular signaling mostly results in oxidative stress, as detected in mesangial cells cultured with aberrantly glycosylated IgA or IgA aggregates and in renal biopsies of patients with IgAN. Signs of altered oxidation/antioxidation balance have been detected in sera and/or in erythrocytes of patients with IgAN, including increased levels of lipoperoxide or malondialdehyde and reduced activity of superoxide dismutase, catalase and glutathione peroxidase. Moreover, increased levels of a marker of oxidative stress, advanced oxidation protein products (AOPPs), have been reported to be significantly associated with proteinuria and disease progression in patients with IgAN. AOPPs are often carried by albumin and can in turn enhance the oxidative stress in the circulation. Recent research suggests that the nephrotoxicity of aberrantly glycosylated IgA1 in IgAN is enhanced in the presence of systemic signs of oxidative stress, and it is tempting to hypothesize that the level of the oxidative milieu conditions the different expression and progression of IgAN.

  7. Oxidative stress in severe acute illness

    PubMed Central

    Bar-Or, David; Bar-Or, Raphael; Rael, Leonard T.; Brody, Edward N.

    2015-01-01

    The overall redox potential of a cell is primarily determined by oxidizable/reducible chemical pairs, including glutathione–glutathione disulfide, reduced thioredoxin–oxidized thioredoxin, and NAD+–NADH (and NADP–NADPH). Current methods for evaluating oxidative stress rely on detecting levels of individual byproducts of oxidative damage or by determining the total levels or activity of individual antioxidant enzymes. Oxidation–reduction potential (ORP), on the other hand, is an integrated, comprehensive measure of the balance between total (known and unknown) pro-oxidant and antioxidant components in a biological system. Much emphasis has been placed on the role of oxidative stress in chronic diseases, such as Alzheimer's disease and atherosclerosis. The role of oxidative stress in acute diseases often seen in the emergency room and intensive care unit is considerable. New tools for the rapid, inexpensive measurement of both redox potential and total redox capacity should aid in introducing a new body of literature on the role of oxidative stress in acute illness and how to screen and monitor for potentially beneficial pharmacologic agents. PMID:25644686

  8. Role of oxidative stress on platelet hyperreactivity during aging.

    PubMed

    Fuentes, Eduardo; Palomo, Iván

    2016-03-01

    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.

  9. Oxidative Stress Resistance in Deinococcus radiodurans†

    PubMed Central

    Slade, Dea; Radman, Miroslav

    2011-01-01

    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

  10. Radical-free biology of oxidative stress

    PubMed Central

    Jones, Dean P.

    2008-01-01

    Free radical-induced macromolecular damage has been studied extensively as a mechanism of oxidative stress, but large-scale intervention trials with free radical scavenging antioxidant supplements show little benefit in humans. The present review summarizes data supporting a complementary hypothesis for oxidative stress in disease that can occur without free radicals. This hypothesis, which is termed the “redox hypothesis,” is that oxidative stress occurs as a consequence of disruption of thiol redox circuits, which normally function in cell signaling and physiological regulation. The redox states of thiol systems are sensitive to two-electron oxidants and controlled by the thioredoxins (Trx), glutathione (GSH), and cysteine (Cys). Trx and GSH systems are maintained under stable, but nonequilibrium conditions, due to a continuous oxidation of cell thiols at a rate of about 0.5% of the total thiol pool per minute. Redox-sensitive thiols are critical for signal transduction (e.g., H-Ras, PTP-1B), transcription factor binding to DNA (e.g., Nrf-2, nuclear factor-κB), receptor activation (e.g., αIIbβ3 integrin in platelet activation), and other processes. Nonradical oxidants, including peroxides, aldehydes, quinones, and epoxides, are generated enzymatically from both endogenous and exogenous precursors and do not require free radicals as intermediates to oxidize or modify these thiols. Because of the nonequilibrium conditions in the thiol pathways, aberrant generation of nonradical oxidants at rates comparable to normal oxidation may be sufficient to disrupt function. Considerable opportunity exists to elucidate specific thiol control pathways and develop interventional strategies to restore normal redox control and protect against oxidative stress in aging and age-related disease. PMID:18684987

  11. Oxidative Stress Marker and Pregnancy Induced Hypertension

    PubMed Central

    Draganovic, Dragica; Lucic, Nenad; Jojic, Dragica

    2016-01-01

    Background: Pregnancy induced hypertension (PIH) is a state of extremely increased oxidative stress. Hence, research and test of role and significance of oxidative stress in hypertensive disturbance in pregnancy is very important. Aim: Aims of this research were to determine a level of thiobarbituric acid reactive substance (TBARS) as oxidative stress marker in blood of pregnant woman with pregnancy induced hypertension and to analyze correlation of TBARS values with blood pressure values in pregnancy induced hypertensive pregnant women. Patients and methods: Research has been performed at the Clinic of Gynecology and Obstetrics, University Clinical Centre in the Republic of Srpska. It covered 100 pregnant women with hypertension and 100 healthy pregnant women of gestation period from 28 to 40 weeks. Level of TBARS is determined as an equivalent of malondialdehyde standard, in accordance with recommendations by producer (Oxi Select TBARS Analisa Kit). Results: Pregnancy induced hypertension is a state of extremely increased oxidative stress. All pregnant women experiencing hypertension had increased TBARS values in medium value interval over 20 µmol, 66%, whereas in group of healthy pregnant women, only 1% experienced increased TBARS value. Pregnant women with difficult preeclampsia (32%) had high TBARS values, over 40 µmol, and with mild PIH, only 4.9% pregnant women. Conclusion: Pregnant women with pregnancy induced hypertension have extremely increased degree of oxidative stress and lipid peroxidation. TBARS values are in positive correlation with blood pressure values, respectively the highest TBARS value were present in pregnant women with the highest blood pressure values. PMID:28210016

  12. Contribution of mitochondrial oxidative stress to hypertension

    PubMed Central

    Dikalov, Sergey I.; Dikalova, Anna E.

    2016-01-01

    Purpose of review In 1954 Harman proposed the free radical theory of aging, and in 1972 he suggested that mitochondria are both the source and the victim of toxic free radicals. Interestingly, hypertension is age-associated disease and clinical data show that by age 70, 70% of the population has hypertension and this is accompanied by oxidative stress. Antioxidant therapy however is not currently available and common antioxidants like ascorbate and vitamin E are ineffective in preventing hypertension. The present review focuses on molecular mechanisms of mitochondrial oxidative stress and therapeutic potential of targeting mitochondria in hypertension. Recent findings In the past several years, we have shown that the mitochondria become dysfunctional in hypertension and have defined novel role of mitochondrial superoxide radicals in this disease. We have shown that genetic manipulation of mitochondrial antioxidant enzyme superoxide dismutase (SOD2) affects blood pressure and have developed mitochondria-targeted therapies such as SOD2 mimetics that effectively lower blood pressure. The specific mechanism of mitochondrial oxidative stress in hypertension, however, remains unclear. Recent animal and clinical studies have demonstrated several hormonal, metabolic, inflammatory, and environmental pathways contributing to mitochondrial dysfunction and oxidative stress. Summary Nutritional supplements, calorie restriction, and life style change are the most effective preventive strategies to improve mitochondrial function and reduce mitochondrial oxidative stress. Aging associated mitochondrial dysfunction, however, reduces efficacy of these strategies. Therefore, we propose that new classes of mitochondria-targeted antioxidants can provide high therapeutic potential to improve endothelial function and reduce hypertension. PMID:26717313

  13. Repression of gene expression by oxidative stress.

    PubMed Central

    Morel, Y; Barouki, R

    1999-01-01

    Gene expression is modulated by both physiological signals (hormones, cytokines, etc.) and environmental stimuli (physical parameters, xenobiotics, etc.). Oxidative stress appears to be a key pleiotropic modulator which may be involved in either pathway. Indeed, reactive oxygen species (ROS) have been described as second messengers for several growth factors and cytokines, but have also been shown to rise following cellular insults such as xenobiotic metabolism or enzymic deficiency. Extensive studies on the induction of stress-response genes by oxidative stress have been reported. In contrast, owing to the historical focus on gene induction, less attention has been paid to gene repression by ROS. However, a growing number of studies have shown that moderate (i.e. non-cytotoxic) oxidative stress specifically down-regulates the expression of various genes. In this review, we describe the alteration of several physiological functions resulting from oxidative-stress-mediated inhibition of gene transcription. We will then focus on the repressive oxidative modulation of various transcription factors elicited by ROS. PMID:10477257

  14. Diabetic Cardiovascular Disease Induced by Oxidative Stress

    PubMed Central

    Kayama, Yosuke; Raaz, Uwe; Jagger, Ann; Adam, Matti; Schellinger, Isabel N.; Sakamoto, Masaya; Suzuki, Hirofumi; Toyama, Kensuke; Spin, Joshua M.; Tsao, Philip S.

    2015-01-01

    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. PMID:26512646

  15. The impact of oxidative stress on hair.

    PubMed

    Trüeb, R M

    2015-12-01

    Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to detoxify the reactive intermediates or to repair the resulting damage. Reactive oxygen species or free radicals are highly reactive molecules that can directly damage lipids, proteins, and DNA. They are generated by a multitude of endogenous and environmental challenges, while the body possesses endogenous defense mechanisms. With age, production of free radicals increases, while the endogenous defense mechanisms decrease. This imbalance leads to progressive damage of cellular structures, presumably resulting in the aging phenotype. While the role of oxidative stress has been widely discussed in skin aging, little focus has been placed on its impact on hair condition. Moreover, most literature on age-related hair changes focuses on alopecia, but it is equally important that the hair fibers that emerge from the scalp exhibit significant age-related changes that have equal impact on the overall cosmetic properties of hair. Sources of oxidative stress with impact on the pre-emerging fiber include: oxidative metabolism, smoking, UVR, and inflammation from microbial, pollutant, or irritant origins. Sources of oxidative stress with impact on the post-emerging fiber include: UVR (enhanced by copper), chemical insults, and oxidized scalp lipids. The role of the dermatologist is recognition and treatment of pre- and post-emerging factors for lifetime scalp and hair health.

  16. Potential markers of oxidative stress in stroke.

    PubMed

    Cherubini, Antonio; Ruggiero, Carmelinda; Polidori, M Cristina; Mecocci, Patrizia

    2005-10-01

    Free radical production is increased in ischemic and hemorrhagic stroke, leading to oxidative stress that contributes to brain damage. The measurement of oxidative stress in stroke would be extremely important for a better understanding of its pathophysiology and for identifying subgroups of patients that might receive targeted therapeutic intervention. Since direct measurement of free radicals and oxidized molecules in the brain is difficult in humans, several biological substances have been investigated as potential peripheral markers. Among lipid peroxidation products, malondialdehyde, despite its relevant methodological limitations, is correlated with the size of ischemic stroke and clinical outcome, while F2-isoprostanes appear to be promising, but they have not been adequately evaluated. 8-Hydroxy-2-deoxyguanosine has been extensively investigated as markers of oxidative DNA damage but no study has been done in stroke patients. Also enzymatic and nonenzymatic antioxidants have been proposed as indirect markers. Among them ascorbic acid, alpha-tocopherol, uric acid, and superoxide dismutase are related to brain damage and clinical outcome. After a critical evaluation of the literature, we conclude that, while an ideal biomarker is not yet available, the balance between antioxidants and by-products of oxidative stress in the organism might be the best approach for the evaluation of oxidative stress in stroke patients.

  17. The dysregulation of endoplasmic reticulum stress response in acute-on-chronic liver failure patients caused by acute exacerbation of chronic hepatitis B.

    PubMed

    Ren, F; Shi, H; Zhang, L; Zhang, X; Wen, T; Xie, B; Zheng, S; Chen, Y; Li, L; Chen, D; Duan, Z

    2016-01-01

    Although endoplasmic reticulum (ER) stress is critical in various liver diseases, its role in acute-on-chronic liver failure (AoCLF) caused by acute exacerbation of chronic hepatitis B (CHB) is still elusive. This study aimed to analyse ER stress responses in the progression of HBV-related AoCLF. Normal liver tissues (n = 10), liver tissues of CHB (n = 12) and HBV-related patients with AoCLF (n = 19) were used. Electron microscopy of the ultrastructure of the ER was carried out on liver specimens. The gene and protein expression levels of ER stress-related genes were measured. We further analysed the correlation between the expression levels of ER stress-related molecules and liver injury. Electron microscopy identified typical features of the ER microstructure in AoCLF subjects. Among the three pathways of unfolded protein responses, the PKR-like ER kinase and inositol-requiring enzyme 1 signalling pathway were activated in CHB subjects and inactivated in AoCLF subjects, while the activating transcription factor 6 signalling pathway was sustained in the activated form during the progression of AoCLF; the expression of glucose-regulated protein (Grp)78 and Grp94 was gradually decreased in AoCLF subjects compared to healthy individuals and CHB subjects, showing a negative correlation with serum ALT, AST and TBIL; moreover, the ER stress-related apoptosis molecules were activated in the progression of acute exacerbation of CHB. The dysregulated ER stress response may play a complicated role in the pathogenesis of AoCLF, and a severe ER stress response may predict the occurrence of AoCLF caused by acute exacerbation of CHB.

  18. Oxidative stress as a mechanism of teratogenesis.

    PubMed

    Hansen, Jason M

    2006-12-01

    Emerging evidence shows that redox-sensitive signal transduction pathways are critical for developmental processes, including proliferation, differentiation, and apoptosis. As a consequence, teratogens that induce oxidative stress (OS) may induce teratogenesis via the misregulation of these same pathways. Many of these pathways are regulated by cellular thiol redox couples, namely glutathione/glutathione disulfide, thioredoxinred/thioredoinox, and cysteine/cystine. This review outlines oxidative stress as a mechanism of teratogenesis through the disruption of thiol-mediated redox signaling. Due to the ability of many known and suspected teratogens to induce oxidative stress and the many signaling pathways that have redox-sensitive components, further research is warranted to fully understand these mechanisms.

  19. Drug-Induced Oxidative Stress and Toxicity

    PubMed Central

    Deavall, Damian G.; Martin, Elizabeth A.; Horner, Judith M.; Roberts, Ruth

    2012-01-01

    Reactive oxygen species (ROS) are a byproduct of normal metabolism and have roles in cell signaling and homeostasis. Species include oxygen radicals and reactive nonradicals. Mechanisms exist that regulate cellular levels of ROS, as their reactive nature may otherwise cause damage to key cellular components including DNA, protein, and lipid. When the cellular antioxidant capacity is exceeded, oxidative stress can result. Pleiotropic deleterious effects of oxidative stress are observed in numerous disease states and are also implicated in a variety of drug-induced toxicities. In this paper, we examine the nature of ROS-induced damage on key cellular targets of oxidative stress. We also review evidence implicating ROS in clinically relevant, drug-related side effects including doxorubicin-induced cardiac damage, azidothymidine-induced myopathy, and cisplatin-induced ototoxicity. PMID:22919381

  20. Oxidative stress and mitochondrial dysfunction in sepsis.

    PubMed

    Galley, H F

    2011-07-01

    Sepsis-related organ dysfunction remains the most common cause of death in the intensive care unit (ICU), despite advances in healthcare and science. Marked oxidative stress as a result of the inflammatory responses inherent with sepsis initiates changes in mitochondrial function which may result in organ damage. Normally, a complex system of interacting antioxidant defences is able to combat oxidative stress and prevents damage to mitochondria. Despite the accepted role that oxidative stress-mediated injury plays in the development of organ failure, there is still little conclusive evidence of any beneficial effect of systemic antioxidant supplementation in patients with sepsis and organ dysfunction. It has been suggested, however, that antioxidant therapy delivered specifically to mitochondria may be useful.

  1. Oxidative stress in development: nature or nurture?

    PubMed

    Dennery, Phyllis A

    2010-10-15

    An unavoidable consequence of aerobic respiration is the generation of reactive oxygen species (ROS). These may negatively impact development. Nevertheless, a certain amount of oxidative stress is required to allow for the normal progression of embryonic and fetal growth. Alterations in placental oxidative stress results in altered placental function and ultimately altered fetal growth and/or developmental programming leading to long-term consequences into adulthood. This article reviews the role of redox in fetal development and will focus on how developmental programming is influenced by the fetal and placental redox state as well as discuss potential therapeutic interventions.

  2. Involvement of oxidative stress in Alzheimer disease.

    PubMed

    Nunomura, Akihiko; Castellani, Rudy J; Zhu, Xiongwei; Moreira, Paula I; Perry, George; Smith, Mark A

    2006-07-01

    Genetic and lifestyle-related risk factors for Alzheimer disease (AD) are associated with an increase in oxidative stress, suggesting that oxidative stress is involved at an early stage of the pathologic cascade. Moreover, oxidative stress is mechanistically and chronologically associated with other key features of AD, namely, metabolic, mitochondrial, metal, and cell-cycle abnormalities. Contrary to the commonly held notion that pathologic hallmarks of AD signify etiology, several lines of evidence now indicate that aggregation of amyloid-beta and tau is a compensatory response to underlying oxidative stress. Therefore, removal of proteinaceous accumulations may treat the epiphenomenon rather than the disease and may actually enhance oxidative damage. Although some antioxidants have been shown to reduce the incidence of AD, the magnitude of the effect may be modified by individual factors such as genetic predisposition (e.g. apolipoprotein E genotype) and habitual behaviors. Because caloric restriction, exercise, and intellectual activity have been experimentally shown to promote neuronal survival through enhancement of endogenous antioxidant defenses, a combination of dietary regimen of low total calorie and rich antioxidant nutrients and maintaining physical and intellectual activities may ultimately prove to be one of the most efficacious strategies for AD prevention.

  3. Oxidative stress in brain ischemia.

    PubMed

    Love, S

    1999-01-01

    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

  4. Nitric oxide and oxidative stress in placental explant cultures.

    PubMed

    Goncalves, Juvic M; Casart, Ysabel C; Camejo, María I

    2016-01-01

    Placental explant culture, and cellular cytolysis and cellular differentiation have been previously studied. However, oxidative stress and nitric oxide profiles have not been evaluated in these systems. The aim of this study was to determine the release of lipid peroxidation and nitric oxide from placental explants cultured over a seven day period. Placental explants were maintained for seven days in culture and the medium was changed every 24 hours. The response was assessed in terms of syncytiotrophoblast differentiation (human chorionic gonadotropin, hCG), cellular cytolysis (lactate dehydrogenase, LDH), oxidative stress (thiobarbituric acid reactive substances, TBARS), and nitric oxide (NO). Levels of hCG increased progressively from day two to attain its highest level on days four and five after which it decreased gradually. In contrast, the levels of LDH, TBARS, and NO were elevated in the early days of placental culture when new syncytiotrophoblast from cytotrophoblast were forming and also in the last days of culture when tissue was declining. In conclusion, the levels of NO and lipid peroxidation follow a pattern similar to LDH and contrary to hCG. Future placental explant studies to evaluate oxidative stress and NO should consider the physiological changes inherent during the time of culture.

  5. Potential Modulation of Sirtuins by Oxidative Stress

    PubMed Central

    Santos, Leonardo; Escande, Carlos; Denicola, Ana

    2016-01-01

    Sirtuins are a conserved family of NAD-dependent protein deacylases. Initially proposed as histone deacetylases, it is now known that they act on a variety of proteins including transcription factors and metabolic enzymes, having a key role in the regulation of cellular homeostasis. Seven isoforms are identified in mammals (SIRT1–7), all of them sharing a conserved catalytic core and showing differential subcellular localization and activities. Oxidative stress can affect the activity of sirtuins at different levels: expression, posttranslational modifications, protein-protein interactions, and NAD levels. Mild oxidative stress induces the expression of sirtuins as a compensatory mechanism, while harsh or prolonged oxidant conditions result in dysfunctional modified sirtuins more prone to degradation by the proteasome. Oxidative posttranslational modifications have been identified in vitro and in vivo, in particular cysteine oxidation and tyrosine nitration. In addition, oxidative stress can alter the interaction with other proteins, like SIRT1 with its protein inhibitor DBC1 resulting in a net increase of deacetylase activity. In the same way, manipulation of cellular NAD levels by pharmacological inhibition of other NAD-consuming enzymes results in activation of SIRT1 and protection against obesity-related pathologies. Nevertheless, further research is needed to establish the molecular mechanisms of redox regulation of sirtuins to further design adequate pharmacological interventions. PMID:26788256

  6. Role of inducible nitric oxide synthase on the development of virus-associated asthma exacerbation which is dependent on Th1 and Th17 cell responses

    PubMed Central

    Shin, Tae-Seop; Lee, Byung-Jae; Tae, You-Me; Kim, You-Sun; Jeon, Seong Gyu; Gho, Yong Song; Choi, Dong-Chull

    2010-01-01

    Asthma is characterized by airway inflammation induced by immune dysfunction to inhaled antigens. Although respiratory viral infections are the most common cause of asthma exacerbation, immunologic mechanisms underlying virus-associated asthma exacerbation are controversial. Clinical evidence indicates that nitric oxide (NO) levels in exhaled air are increased in exacerbated asthma patients compared to stable patients. Here, we evaluated the immunologic mechanisms and the role of NO synthases (NOSs) in the development of virus-associated asthma exacerbation. A murine model of virus-associated asthma exacerbation was established using intranasal challenge with ovalbumin (OVA) plus dsRNA for 4 weeks in mice sensitized with OVA plus dsRNA. Lung infiltration of inflammatory cells, especially neutrophils, was increased by repeated challenge with OVA plus dsRNA, as compared to OVA alone. The neutrophilic inflammation enhanced by dsRNA was partly abolished in the absence of IFN-gamma or IL-17 gene expression, whereas unaffected in the absence of IL-13. In terms of the roles of NOSs, dsRNA-enhanced neutrophilic inflammation was significantly decreased in inducible NOS (iNOS)-deficient mice compared to wild type controls; in addition, this phenotype was inhibited by treatment with a non-specific NOS inhibitor (L-NAME) or an specific inhibitor (1400 W), but not with a specific endothelial NOS inhibitor (AP-CAV peptide). Taken together, these findings suggest that iNOS pathway is important in the development of virus-associated exacerbation of neutrophilic inflammation, which is dependent on both Th1 and Th17 cell responses. PMID:20841959

  7. Inhibition of Adenylyl Cyclase Type 5 Increases Longevity and Healthful Aging through Oxidative Stress Protection

    PubMed Central

    Vatner, Stephen F.; Pachon, Ronald E.; Vatner, Dorothy E.

    2015-01-01

    Mice with disruption of adenylyl cyclase type 5 (AC5 knockout, KO) live a third longer than littermates. The mechanism, in part, involves the MEK/ERK pathway, which in turn is related to protection against oxidative stress. The AC5 KO model also protects against diabetes, obesity, and the cardiomyopathy induced by aging, diabetes, and cardiac stress and also demonstrates improved exercise capacity. All of these salutary features are also mediated, in part, by oxidative stress protection. For example, chronic beta adrenergic receptor stimulation induced cardiomyopathy was rescued by AC5 KO. Conversely, in AC5 transgenic (Tg) mice, where AC5 is overexpressed in the heart, the cardiomyopathy was exacerbated and was rescued by enhancing oxidative stress resistance. Thus, the AC5 KO model, which resists oxidative stress, is uniquely designed for clinical translation, since it not only increases longevity and exercise, but also protects against diabetes, obesity, and cardiomyopathy. Importantly, inhibition of AC5's action to prolong longevity and enhance healthful aging, as well as its mechanism through resistance to oxidative stress, is unique among all of the nine AC isoforms. PMID:25945149

  8. Hypoxia. 1. Intracellular sensors for oxygen and oxidative stress: novel therapeutic targets.

    PubMed

    Miyata, Toshio; Takizawa, Shunya; van Ypersele de Strihou, Charles

    2011-02-01

    A variety of human disorders, e.g., ischemic heart disease, stroke, kidney disease, eventually share the deleterious consequences of a common, hypoxic and oxidative stress pathway. In this review, we utilize recent information on the cellular defense mechanisms against hypoxia and oxidative stress with the hope to propose new therapeutic tools. The hypoxia-inducible factor (HIF) is a key player as it activates a broad range of genes protecting cells against hypoxia. Its level is determined by its degradation rate by intracellular oxygen sensors prolyl hydroxylases (PHDs). There are three different PHD isoforms (PHD1-3). Small molecule PHD inhibitors improve hypoxic injury in experimental animals but, unfortunately, may induce adverse effects associated with PHD2 inhibition, e.g., angiogenesis. As yet, no inhibitor specific for a distinct PHD isoform is currently available. Still, the specific disruption of the PHD1 gene is known to induce hypoxic tolerance, without angiogenesis and erythrocytosis, by reprogramming basal oxygen metabolism with an attendant decreased oxidative stress in hypoxic mitochondria. A specific PHD1 inhibitor might therefore offer a novel therapy against hypoxia. The nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) regulates the basal and inducible expression of numerous antioxidant stress genes. Disruption of its gene exacerbates oxidative tissue injury. Nrf2 activity is modulated by Kelch-like ECH-associated protein 1 (Keap1), an intracellular sensor for oxidative stress. Inhibitors of Keap 1 may prove therapeutic against oxidative tissue injury.

  9. Attenuation of cold stress-induced exacerbation of cardiac and adipose tissue pathology and metabolic disorders in a rat model of metabolic syndrome by the glucocorticoid receptor antagonist RU486

    PubMed Central

    Nagasawa, K; Matsuura, N; Takeshita, Y; Ito, S; Sano, Y; Yamada, Y; Uchinaka, A; Murohara, T; Nagata, K

    2016-01-01

    Objectives: Chronic stress affects the central nervous system as well as endocrine, metabolic and immune systems. However, the effects of cold stress on cardiovascular and metabolic disorders in metabolic syndrome (MetS) have remained unclear. We recently characterized DahlS.Z-Leprfa/Leprfa (DS/obese) rats, derived from a cross between Dahl salt-sensitive and Zucker rats, as a new animal model of MetS. We have now investigated the effects of chronic cold stress and glucocorticoid receptor (GR) blockade on cardiac and adipose tissue pathology as well as on metabolic parameters in this model. Methods: DS/obese rats were exposed to cold stress (immersion in ice-cold water to a depth of 1–2 cm for 2 h per day) with or without subcutaneous injection of the GR antagonist RU486 (2 mg kg−1day−1) for 4 weeks beginning at 9 weeks of age. Age-matched homozygous lean (DahlS.Z-Lepr+/Lepr+) littermates served as a control. Results: Chronic cold stress exacerbated hypertension as well as left ventricular (LV) hypertrophy, fibrosis and diastolic dysfunction in DS/obese rats in a manner sensitive to RU486 treatment. Cold stress with or without RU486 did not affect body weight or fat mass. In contrast, cold stress further increased cardiac oxidative stress as well as macrophage infiltration and proinflammatory gene expression in LV and visceral fat tissue, with all of these effects being attenuated by RU486. Cold stress also further increased GR and 11β-hydroxysteroid dehydrogenase type 1 mRNA and protein abundance in LV and visceral adipose tissue, and these effects were again inhibited by RU486. In addition, RU486 ameliorated the stress-induced aggravation of dyslipidemia, glucose intolerance and insulin resistance in DS/obese rats. Conclusions: Our results implicate GR signaling in cold stress-induced exacerbation of cardiac and adipose tissue pathology as well as of abnormal glucose and lipid metabolism in a rat model of MetS. PMID:27110688

  10. Good Stress, Bad Stress and Oxidative Stress: Insights from Anticipatory Cortisol Reactivity

    PubMed Central

    Aschbacher, Kirstin; O'Donovan, Aoife; Wolkowitz, Owen M.; Dhabhar, Firdaus S.; Su, Yali; Epel, Elissa

    2014-01-01

    Chronic psychological stress appears to accelerate biological aging, and oxidative damage is an important potential mediator of this process. However, the mechanisms by which psychological stress promotes oxidative damage are poorly understood. This study investigates the theory that cortisol increases in response to an acutely stressful event have the potential to either enhance or undermine psychobiological resilience to oxidative damage, depending on the body's prior exposure to chronic psychological stress. In order to achieve a range of chronic stress exposure, forty-eight post-menopausal women were recruited in a case-control design that matched women caring for spouses with dementia (a chronic stress model) with similarly aged control women whose spouses were healthy. Participants completed a questionnaire assessing perceived stress over the previous month and provided fasting blood. Three markers of oxidative damage were assessed: 8-iso-prostaglandin F2α (IsoP), lipid peroxidation, 8-hydroxyguanosine (8-OxoG) and 8-hydroxy-2′-deoxyguanosine (8-OHdG), reflecting oxidative damage to RNA/DNA respectively. Within approximately one week, participants completed a standardized acute laboratory stress task while salivary cortisol responses were measured. The increase from 0 to 30 min was defined as “peak” cortisol reactivity, while the increase from 0 to 15 min was defined as “anticipatory” cortisol reactivity, representing a cortisol response that began while preparing for the stress task. Women under chronic stress had higher 8-oxoG, oxidative damage to RNA (p<.01). A moderated mediation model was tested, in which it was hypothesized that heightened anticipatory cortisol reactivity would mediate the relationship between perceived stress and elevated oxidative stress damage, but only among women under chronic stress. Consistent with this model, bootstrapped path analysis found significant indirect paths from perceived stress to 8-OxoG and IsoP (but not

  11. Good stress, bad stress and oxidative stress: insights from anticipatory cortisol reactivity.

    PubMed

    Aschbacher, Kirstin; O'Donovan, Aoife; Wolkowitz, Owen M; Dhabhar, Firdaus S; Su, Yali; Epel, Elissa

    2013-09-01

    Chronic psychological stress appears to accelerate biological aging, and oxidative damage is an important potential mediator of this process. However, the mechanisms by which psychological stress promotes oxidative damage are poorly understood. This study investigates the theory that cortisol increases in response to an acutely stressful event have the potential to either enhance or undermine psychobiological resilience to oxidative damage, depending on the body's prior exposure to chronic psychological stress. In order to achieve a range of chronic stress exposure, forty-eight post-menopausal women were recruited in a case-control design that matched women caring for spouses with dementia (a chronic stress model) with similarly aged control women whose spouses were healthy. Participants completed a questionnaire assessing perceived stress over the previous month and provided fasting blood. Three markers of oxidative damage were assessed: 8-iso-prostaglandin F(2α) (IsoP), lipid peroxidation, 8-hydroxyguanosine (8-oxoG) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), reflecting oxidative damage to RNA/DNA respectively. Within approximately one week, participants completed a standardized acute laboratory stress task while salivary cortisol responses were measured. The increase from 0 to 30 min was defined as "peak" cortisol reactivity, while the increase from 0 to 15 min was defined as "anticipatory" cortisol reactivity, representing a cortisol response that began while preparing for the stress task. Women under chronic stress had higher 8-oxoG, oxidative damage to RNA (p<.01). A moderated mediation model was tested, in which it was hypothesized that heightened anticipatory cortisol reactivity would mediate the relationship between perceived stress and elevated oxidative stress damage, but only among women under chronic stress. Consistent with this model, bootstrapped path analysis found significant indirect paths from perceived stress to 8-oxoG and IsoP (but not 8-OHd

  12. Oxidative stress markers in affective disorders.

    PubMed

    Siwek, Marcin; Sowa-Kućma, Magdalena; Dudek, Dominika; Styczeń, Krzysztof; Szewczyk, Bernadeta; Kotarska, Katarzyna; Misztakk, Paulina; Pilc, Agnieszka; Wolak, Małgorzata; Nowak, Gabriel

    2013-01-01

    Affective disorders are a medical condition with a complex biological pattern of etiology, involving genetic and epigenetic factors, along with different environmental stressors. Increasing numbers of studies indicate that induction of oxidative and nitrosative stress (O&NS) pathways, which is accompanied by immune-inflammatory response, might play an important role in the pathogenic mechanisms underlying many major psychiatric disorders, including depression and bipolar disorder. Reactive oxygen and nitrogen species have been shown to impair the brain function by modulating activity of principal neurotransmitter (e.g., glutamatergic) systems involved in the neurobiology of depression. Both preclinical and clinical studies revealed that depression is associated with altered levels of oxidative stress markers and typically reduced concentrations of several endogenous antioxidant compounds, such as glutathione, vitamin E, zinc and coenzyme Q10, or enzymes, including glutathione peroxidase, and with an impairment of the total antioxidant status. These oxidative stress parameters can be normalized by successful antidepressant therapy. On the other hand, some antioxidants (zinc, N-acetylcysteine, omega-3 free fatty acids) may exhibit antidepressant properties or enhance standard antidepressant therapy. These observations introduce new potential targets for the development of therapeutic interventions based on antioxidant compounds. The present paper reviews selected animal and human studies providing evidence that oxidative stress is implicated in the pathophysiology and treatment of depression and bipolar disorder.

  13. Interdependence of tetrapyrrole metabolism, the generation of oxidative stress and the mitigative oxidative stress response

    PubMed Central

    Busch, Andrea W.U.; Montgomery, Beronda L.

    2015-01-01

    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. PMID:25618582

  14. Interdependence of tetrapyrrole metabolism, the generation of oxidative stress and the mitigative oxidative stress response.

    PubMed

    Busch, Andrea W U; Montgomery, Beronda L

    2015-01-01

    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.

  15. Oxidative stress in benign prostate hyperplasia.

    PubMed

    Zabaiou, N; Mabed, D; Lobaccaro, J M; Lahouel, M

    2016-02-01

    To assess the status of oxidative stress in benign prostate hyperplasia, a very common disease in older men which constitutes a public health problem in Jijel, prostate tissues were obtained by transvesical adenomectomy from 10 men with benign prostate hyperplasia. We measured the cytosolic levels of malondialdehyde (MDA) and glutathione (GSH) and cytosolic enzyme activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferase. The development of benign prostate hyperplasia is accompanied by impaired oxidative status by increasing levels of MDA, depletion of GSH concentrations and a decrease in the activity of all the antioxidant enzymes studied. These results have allowed us to understand a part of the aetiology of benign prostate hyperplasia related to oxidative stress.

  16. Oxidative stress, phototherapy and the neonate.

    PubMed

    Gathwala, G; Sharma, S

    2000-11-01

    Phototherapy is the most widely used form of therapy for unconjugated hyperbilirubinaemia. Its non-invasive nature and few side effects reported earlier have led to the assumption that it is innocuous. Recent research has revealed that phototherapy is a photodynamic stress and can induce lipid peroxidation. There is increasing evidence that many severe diseases of the neonate are caused by oxidative injury and lipid peroxidation. In the present communique, we review the oxidative susceptibility of the neonate and the evidence now available that phototherapy induces oxidative stress. Although intensive phototherapy (up to 40 mwatt/cm2/nm) has been reported to be increasingly effective, a little caution, we believe is warranted, till more definite data in the human neonate, help resolve the issue.

  17. Current perspectives of oxidative stress and its measurement in chronic obstructive pulmonary disease.

    PubMed

    Lin, Jiun-Lih; Thomas, Paul S

    2010-08-01

    Cigarette smoking, the principal aetiology of chronic obstructive pulmonary disease (COPD) in the developed countries, delivers and generates oxidative stress within the lungs. This imbalance of oxidant burden and antioxidant capacity has been implicated as an important contributing factor in the pathogenesis of COPD. Oxidative processes and free radical generation orchestrate the inflammation, mucous gland hyperplasia, and apoptosis of the airway lining epithelium which characterises COPD. Pivotal oxidative stress/pro-inflammatory molecules include reactive oxygen species such as the superoxides and hydroxyl radicals, pro-inflammatory cytokines including leukotrienes, interleukins, tumour necrosis factor alpha, and activated transcriptional factors such as nuclear factor kappa-B and activator protein 1. The lung has a large reserve of antioxidant agents such as glutathione and superoxide dismutase to counter oxidants. However, smoking also causes the depletion of antioxidants, which further contributes to oxidative tissue damage. The downregulation of antioxidant pathways has also been associated with acute exacerbations of COPD. The delivery of redox-protective antioxidants may have preventative and therapeutic potential of COPD. Although these observations have yet to translate into common clinical practice, preliminary clinical trials and studies of animal models have shown that interventions to counter this oxidative imbalance may have potential to better manage COPD. There is, thus, a need for the ability to monitor such interventions and exhaled breath condensate is rapidly emerging as a novel and noninvasive approach in the sampling of airway epithelial lining fluid which could be used for repeated analysis of oxidative stress and inflammation in the lungs.

  18. Avocado Oil Improves Mitochondrial Function and Decreases Oxidative Stress in Brain of Diabetic Rats.

    PubMed

    Ortiz-Avila, Omar; Esquivel-Martínez, Mauricio; Olmos-Orizaba, Berenice Eridani; Saavedra-Molina, Alfredo; Rodriguez-Orozco, Alain R; Cortés-Rojo, Christian

    2015-01-01

    Diabetic encephalopathy is a diabetic complication related to the metabolic alterations featuring diabetes. Diabetes is characterized by increased lipid peroxidation, altered glutathione redox status, exacerbated levels of ROS, and mitochondrial dysfunction. Although the pathophysiology of diabetic encephalopathy remains to be clarified, oxidative stress and mitochondrial dysfunction play a crucial role in the pathogenesis of chronic diabetic complications. Taking this into consideration, the aim of this work was to evaluate the effects of 90-day avocado oil intake in brain mitochondrial function and oxidative status in streptozotocin-induced diabetic rats (STZ rats). Avocado oil improves brain mitochondrial function in diabetic rats preventing impairment of mitochondrial respiration and mitochondrial membrane potential (ΔΨ m ), besides increasing complex III activity. Avocado oil also decreased ROS levels and lipid peroxidation and improved the GSH/GSSG ratio as well. These results demonstrate that avocado oil supplementation prevents brain mitochondrial dysfunction induced by diabetes in association with decreased oxidative stress.

  19. Avocado Oil Improves Mitochondrial Function and Decreases Oxidative Stress in Brain of Diabetic Rats

    PubMed Central

    Ortiz-Avila, Omar; Esquivel-Martínez, Mauricio; Olmos-Orizaba, Berenice Eridani; Saavedra-Molina, Alfredo; Rodriguez-Orozco, Alain R.; Cortés-Rojo, Christian

    2015-01-01

    Diabetic encephalopathy is a diabetic complication related to the metabolic alterations featuring diabetes. Diabetes is characterized by increased lipid peroxidation, altered glutathione redox status, exacerbated levels of ROS, and mitochondrial dysfunction. Although the pathophysiology of diabetic encephalopathy remains to be clarified, oxidative stress and mitochondrial dysfunction play a crucial role in the pathogenesis of chronic diabetic complications. Taking this into consideration, the aim of this work was to evaluate the effects of 90-day avocado oil intake in brain mitochondrial function and oxidative status in streptozotocin-induced diabetic rats (STZ rats). Avocado oil improves brain mitochondrial function in diabetic rats preventing impairment of mitochondrial respiration and mitochondrial membrane potential (ΔΨm), besides increasing complex III activity. Avocado oil also decreased ROS levels and lipid peroxidation and improved the GSH/GSSG ratio as well. These results demonstrate that avocado oil supplementation prevents brain mitochondrial dysfunction induced by diabetes in association with decreased oxidative stress. PMID:26180820

  20. Methylglyoxal promotes oxidative stress and endothelial dysfunction.

    PubMed

    Sena, Cristina M; Matafome, Paulo; Crisóstomo, Joana; Rodrigues, Lisa; Fernandes, Rosa; Pereira, Paulo; Seiça, Raquel M

    2012-05-01

    Modern diets can cause modern diseases. Research has linked a metabolite of sugar, methylglyoxal (MG), to the development of diabetic complications, but the exact mechanism has not been fully elucidated. The present study was designed to investigate whether MG could directly influence endothelial function, oxidative stress and inflammation in Wistar and Goto-Kakizaki (GK) rats, an animal model of type 2 diabetes. Wistar and GK rats treated with MG in the drinking water for 3 months were compared with the respective control rats. The effects of MG were investigated on NO-dependent vasorelaxation in isolated rat aortic arteries from the different groups. Insulin resistance, NO bioavailability, glycation, a pro-inflammatory biomarker monocyte chemoattractant protein-1 (MCP-1) and vascular oxidative stress were also evaluated. Methylglyoxal treated Wistar rats significantly reduced the efficacy of NO-dependent vasorelaxation (p<0.001). This impairment was accompanied by a three fold increase in the oxidative stress marker nitrotyrosine. Advanced glycation endproducts (AGEs) formation was significantly increased as well as MCP-1 and the expression of the receptor for AGEs (RAGE). NO bioavailability was significantly attenuated and accompanied by an increase in superoxide anion immunofluorescence. Methylglyoxal treated GK rats significantly aggravated endothelial dysfunction, oxidative stress, AGEs accumulation and diminished NO bioavailability when compared with control GK rats. These results indicate that methylglyoxal induced endothelial dysfunction in normal Wistar rats and aggravated the endothelial dysfunction present in GK rats. The mechanism is at least in part by increasing oxidative stress and/or AGEs formation with a concomitant increment of inflammation and a decrement in NO bioavailability. The present study provides further evidence for methylglyoxal as one of the causative factors in the pathogenesis of atherosclerosis and development of macrovascular

  1. Piracetam improves mitochondrial dysfunction following oxidative stress.

    PubMed

    Keil, Uta; Scherping, Isabel; Hauptmann, Susanne; Schuessel, Katin; Eckert, Anne; Müller, Walter E

    2006-01-01

    1.--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. 2.--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. 3.--Piracetam treatment at concentrations between 100 and 1000 microM 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 microM) induced a nearly complete recovery of mitochondrial membrane potential and ATP levels. Piracetam also reduced caspase 9 activity after SNP treatment. 4.--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. 5.--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.

  2. Inflammatory and oxidative stress in rotavirus infection

    PubMed Central

    Guerrero, Carlos A; Acosta, Orlando

    2016-01-01

    Rotaviruses are the single leading cause of life-threatening diarrhea affecting children under 5 years of age. Rotavirus entry into the host cell seems to occur by sequential interactions between virion proteins and various cell surface molecules. The entry mechanisms seem to involve the contribution of cellular molecules having binding, chaperoning and oxido-reducing activities. It appears to be that the receptor usage and tropism of rotaviruses is determined by the species, cell line and rotavirus strain. Rotaviruses have evolved functions which can antagonize the host innate immune response, whereas are able to induce endoplasmic reticulum (ER) stress, oxidative stress and inflammatory signaling. A networking between ER stress, inflammation and oxidative stress is suggested, in which release of calcium from the ER increases the generation of mitochondrial reactive oxygen species (ROS) leading to toxic accumulation of ROS within ER and mitochondria. Sustained ER stress potentially stimulates inflammatory response through unfolded protein response pathways. However, the detailed characterization of the molecular mechanisms underpinning these rotavirus-induced stressful conditions is still lacking. The signaling events triggered by host recognition of virus-associated molecular patterns offers an opportunity for the development of novel therapeutic strategies aimed at interfering with rotavirus infection. The use of N-acetylcysteine, non-steroidal anti-inflammatory drugs and PPARγ agonists to inhibit rotavirus infection opens a new way for treating the rotavirus-induced diarrhea and complementing vaccines. PMID:27175349

  3. Multimarker Screening of Oxidative Stress in Aging

    PubMed Central

    Syslová, Kamila; Böhmová, Adéla; Kuzma, Marek; Pelclová, Daniela; Kačer, Petr

    2014-01-01

    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. PMID:25147595

  4. [Mitochondria, oxidative stress and aging].

    PubMed

    Szarka, András; Bánhegyi, Gábor; Sümegi, Balázs

    2014-03-23

    The free radical theory of aging was defined in the 1950s. On the base of this theory, the reactive oxygen species formed in the metabolic pathways can play pivotal role in ageing. The theory was modified by defining the mitochondrial respiration as the major cellular source of reactive oxygen species and got the new name mitochondrial theory of aging. Later on the existence of a "vicious cycle" was proposed, in which the reactive oxygen species formed in the mitochondrial respiration impair the mitochondrial DNA and its functions. The formation of reactive oxygen species are elevated due to mitochondrial dysfunction. The formation of mitochondrial DNA mutations can be accelerated by this "vicious cycle", which can lead to accelerated aging. The exonuclease activity of DNA polymerase γ, the polymerase responsible for the replication of mitochondrial DNA was impaired in mtDNA mutator mouse recently. The rate of somatic mutations in mitochondrial DNA was elevated and an aging phenotype could have been observed in these mice. Surprisingly, no oxidative impairment neither elevated reactive oxygen species formation could have been observed in the mtDNA mutator mice, which may question the existence of the "vicious cycle".

  5. Oxidative stress and carbon metabolism influence Aspergillus flavus transcriptome composition and secondary metabolite production

    PubMed Central

    Fountain, Jake C.; Bajaj, Prasad; Pandey, Manish; Nayak, Spurthi N.; Yang, Liming; Kumar, Vinay; Jayale, Ashwin S.; Chitikineni, Anu; Zhuang, Weijian; Scully, Brian T.; Lee, R. Dewey; Kemerait, Robert C.; Varshney, Rajeev K.; Guo, Baozhu

    2016-01-01

    Contamination of crops with aflatoxin is a serious global threat to food safety. Aflatoxin production by Aspergillus flavus is exacerbated by drought stress in the field and by oxidative stress in vitro. We examined transcriptomes of three toxigenic and three atoxigenic isolates of A. flavus in aflatoxin conducive and non-conducive media with varying levels of H2O2 to investigate the relationship of secondary metabolite production, carbon source, and oxidative stress. We found that toxigenic and atoxigenic isolates employ distinct mechanisms to remediate oxidative damage, and that carbon source affected the isolates’ expression profiles. Iron metabolism, monooxygenases, and secondary metabolism appeared to participate in isolate oxidative responses. The results suggest that aflatoxin and aflatrem biosynthesis may remediate oxidative stress by consuming excess oxygen and that kojic acid production may limit iron-mediated, non-enzymatic generation of reactive oxygen species. Together, secondary metabolite production may enhance A. flavus stress tolerance, and may be reduced by enhancing host plant tissue antioxidant capacity though genetic improvement by breeding selection. PMID:27941917

  6. Oxidative Stress: A Promising Target for Chemoprevention

    PubMed Central

    John, AM Sashi Papu; Ankem, Murali K; Damodaran, Chendil

    2016-01-01

    Cancer is a leading cause of death worldwide, and treating advanced stages of cancer remains clinically challenging. Epidemiological studies have shown that oxidants and free radicals induced DNA damage is one of the predominant causative factors for cancer pathogenesis. Hence, oxidants are attractive targets for chemoprevention as well as therapy. Dietary agents are known to exert an anti-oxidant property which is one of the most efficient preventive strategy in cancer progression. In this article, we highlight dietary agents can potentially target oxidative stress, in turn delaying, preventing, or treating cancer development. Some of these agents are currently in use in basic research, while some have been launched successfully into clinical trials. PMID:27088073

  7. Electromagnetic Fields, Oxidative Stress, and Neurodegeneration

    PubMed Central

    Consales, Claudia; Merla, Caterina; Marino, Carmela; Benassi, Barbara

    2012-01-01

    Electromagnetic fields (EMFs) originating both from both natural and manmade sources permeate our environment. As people are continuously exposed to EMFs in everyday life, it is a matter of great debate whether they can be harmful to human health. On the basis of two decades of epidemiological studies, an increased risk for childhood leukemia associated with Extremely Low Frequency fields has been consistently assessed, inducing the International Agency for Research on Cancer to insert them in the 2B section of carcinogens in 2001. EMFs interaction with biological systems may cause oxidative stress under certain circumstances. Since free radicals are essential for brain physiological processes and pathological degeneration, research focusing on the possible influence of the EMFs-driven oxidative stress is still in progress, especially in the light of recent studies suggesting that EMFs may contribute to the etiology of neurodegenerative disorders. This review synthesizes the emerging evidences about this topic, highlighting the wide data uncertainty that still characterizes the EMFs effect on oxidative stress modulation, as both pro-oxidant and neuroprotective effects have been documented. Care should be taken to avoid methodological limitations and to determine the patho-physiological relevance of any alteration found in EMFs-exposed biological system. PMID:22991514

  8. Oxidative stress response in Paracoccidioides brasiliensis.

    PubMed

    Campos, Elida G; Jesuino, Rosália Santos Amorim; Dantas, Alessandra da Silva; Brígido, Marcelo de Macedo; Felipe, Maria Sueli S

    2005-06-30

    Survival of pathogenic fungi inside human hosts depends on evasion from the host immune system and adaptation to the host environment. Among different insults that Paracoccidioides brasiliensis has to handle are reactive oxygen and nitrogen species produced by the human host cells, and by its own metabolism. Knowing how the parasite deals with reactive species is important to understand how it establishes infection and survives within humans. The initiative to describe the P. brasiliensis transcriptome fostered new approaches to study oxidative stress response in this organism. By examining genes related to oxidative stress response, one can evaluate the parasite's ability to face this condition and infer about possible ways to overcome this ability. We report the results of a search of the P. brasiliensis assembled expressed sequence tag database for homologous sequences involved in oxidative stress response. We described several genes coding proteins involved in antioxidant defense, for example, catalase and superoxide dismutase isoenzymes, peroxiredoxin, cytochrome c peroxidase, glutathione synthesis enzymes, thioredoxin, and the transcription factors Yap1 and Skn7. The transcriptome analysis of P. brasiliensis reveals a pathogen that has many resources to combat reactive species. Besides characterizing the antioxidant defense system in P. brasiliensis, we also compared the ways in which different fungi respond to oxidative damage, and we identified the basic features of this response.

  9. Aflatoxin production and oxidative stress in Aspergillus flavus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The colonization of crops by Aspergillus flavus results in the production of aflatoxins. Aflatoxin production is also exacerbated by abiotic stresses in the field. Here, we investigated the role of reactive oxygen species (ROS), which accumulate in plant tissues in response to drought and heat stres...

  10. Dual effects of curcumin on neuronal oxidative stress in the presence of Cu(II).

    PubMed

    Huang, Han-Chang; Lin, Chang-Jun; Liu, Wen-Juan; Jiang, Rui-Rui; Jiang, Zhao-Feng

    2011-07-01

    Alzheimer's disease (AD) is one of the most common neurodegenerative disorders. Elevated copper (Cu) ions are thought to link AD pathology. Curcumin is suggested to treat AD because of its high anti-oxidative activity and coordination to transitional metal ions. In this study, the protective effect of curcumin against the Cu(II)-induced oxidative damage was investigated in primary rat cortical neurons. The neuronal damage was assessed by morphological observation, cell viability, and oxidative stress level. The results showed that curcumin at low dosage protected primary cultured neurons from the 20 μM Cu(II)-induced damage. Low dosage of curcumin depressed oxidative stress levels exacerbated by Cu(II). However, high dosage of curcumin failed to decrease the Cu(II)-induced oxidative stress. When Cu(II) was presented in primary neurons, curcumin at high dosage resulted in chromosomal aberration and cell damage. These results suggest that curcumin, in a concentration-dependent manner, plays both anti-oxidative and pro-oxidative roles in primary neurons treated with Cu(II).

  11. Oxidative Stress and Air Pollution Exposure

    PubMed Central

    Lodovici, Maura; Bigagli, Elisabetta

    2011-01-01

    Air pollution is associated with increased cardiovascular and pulmonary morbidity and mortality. The mechanisms of air pollution-induced health effects involve oxidative stress and inflammation. As a matter of fact, particulate matter (PM), especially fine (PM2.5, PM < 2.5 μm) and ultrafine (PM0.1, PM < 0.1 μm) particles, ozone, nitrogen oxides, and transition metals, are potent oxidants or able to generate reactive oxygen species (ROS). Oxidative stress can trigger redox-sensitive pathways that lead to different biological processes such as inflammation and cell death. However, it does appear that the susceptibility of target organ to oxidative injury also depends upon its ability to upregulate protective scavenging systems. As vehicular traffic is known to importantly contribute to PM exposure, its intensity and quality must be strongly relevant determinants of the qualitative characteristics of PM spread in the atmosphere. Change in the composition of this PM is likely to modify its health impact. PMID:21860622

  12. Oxidative stress and inflammatory bowel disease.

    PubMed

    Almenier, Hazem A; Al Menshawy, Hazem H; Maher, Maha M; Al Gamal, Salah

    2012-01-01

    Inflammatory Bowel Disease (IBD) is a chronic relapsing and remitting inflammatory condition of the gastrointestinal tract. The exact cause of IBD remains undetermined, the condition appears to be related to a combination of genetic and environmental factors. While many gaps in our knowledge still exist, the last two decades have witnessed an unprecedented progress not only in the etiology ; but mainly in the mechanisms underlying the chronic inflammatory response, immunologic and genetic aspects. We review some recent points of research in pathogenesis with special stress on oxidative stress and its correlations with disease activity.

  13. Oxidative Stress and Periodontal Disease in Obesity.

    PubMed

    Dursun, Erhan; Akalin, Ferda Alev; Genc, Tolga; Cinar, Nese; Erel, Ozcan; Yildiz, Bulent Okan

    2016-03-01

    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 < 0.05 for all). GCF TOS was higher in the obese women (P < 0.05), whereas there was a nonsignificant trend for higher serum TOS in obese women (P = 0.074). GCF TAOC values showed a negative correlation with body mass index, whereas GCF OSI was positively correlated with fasting insulin and low-density lipoprotein-cholesterol levels (P < 0.05 for all). Clinical periodontal indices showed significant correlations with body mass index, insulin, and lipid levels, and also oxidant status markers

  14. Oxidative Stress and Periodontal Disease in Obesity

    PubMed Central

    Dursun, Erhan; Akalın, Ferda Alev; Genc, Tolga; Cinar, Nese; Erel, Ozcan; Yildiz, Bulent Okan

    2016-01-01

    Abstract 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 < 0.05 for all). GCF TOS was higher in the obese women (P < 0.05), whereas there was a nonsignificant trend for higher serum TOS in obese women (P = 0.074). GCF TAOC values showed a negative correlation with body mass index, whereas GCF OSI was positively correlated with fasting insulin and low-density lipoprotein-cholesterol levels (P < 0.05 for all). Clinical periodontal indices showed significant correlations with body mass index, insulin, and lipid levels, and also oxidant status

  15. ALS and Oxidative Stress: The Neurovascular Scenario

    PubMed Central

    Thakur, Keshav; Gupta, Pawan Kumar

    2013-01-01

    Oxidative stress and angiogenic factors have been placed as the prime focus of scientific investigations after an establishment of link between vascular endothelial growth factor promoter (VEGF), hypoxia, and amyotrophic lateral sclerosis (ALS) pathogenesis. Deletion of the hypoxia-response element in the vascular endothelial growth factor promoter and mutant superoxide dismutase 1 (SOD1) which are characterised by atrophy and muscle weakness resulted in phenotype resembling human ALS in mice. This results in lower motor neurodegeneration thus establishing an important link between motor neuron degeneration, vasculature, and angiogenic molecules. In this review, we have presented human, animal, and in vitro studies which suggest that molecules like VEGF have a therapeutic, diagnostic, and prognostic potential in ALS. Involvement of vascular growth factors and hypoxia response elements also highlights the converging role of oxidative stress and neurovascular network for understanding and treatment of various neurodegenerative disorders like ALS. PMID:24367722

  16. [Atherosclerosis, oxidative stress and physical activity. Review].

    PubMed

    Calderón, Juan Camilo; Fernández, Ana Zita; María de Jesús, Alina Isabel

    2008-09-01

    Atherosclerosis and related diseases have emerged as the leading cause of morbidity and mortality in the western world and, therefore, as a problem of public health. Free radicals and reactive oxygen species have been suggested to be part of the pathophysiology of these diseases. It is well known that physical activity plays an important role as a public health measure by reducing the risk of developing atherosclerosis-related cardiovascular events in the general population. It is also known that physical activity increases in some tissues, the reactive oxygen species production. In this review the atherosclerosis-oxidative stress-physical activity relationship is focused on the apparent paradox by which physical activity reduces atherosclerosis and cardiovascular risk in parallel with the activation of an apparently damaging mechanism which is an increased oxidative stress. A hypothesis including the experimental and clinical evidence is presented to explain the aforementioned paradox.

  17. [Oxidative stress and preeclampsia: A review].

    PubMed

    Guerby, P; Vidal, F; Garoby-Salom, S; Vayssiere, C; Salvayre, R; Parant, O; Negre-Salvayre, A

    2015-11-01

    Preeclampsia is a leading cause of pregnancy complications and affects 3-7% of pregnant women. Pathophysiology of preeclampsia is still unclear. According to the two-stage model of preeclampsia, the abnormal and hypoperfused placenta (stage 1) releases factors to the bloodstream, which are responsible for the maternal symptoms (stage 2), characterised by a systemic inflammation and endothelial dysfunction. Oxidative stress plays an important role in the pathophysiology of the preeclampsia and could be the common denominator between the two. This review summarizes the current knowledge of a new potential etiology of the disease, with a special focus on oxidative stress. We also review the different factors that have been proposed to cause endothelial cell dysfunction in preeclampsia, and trials investigating the role of antioxidant supplementation in preeclampsia.

  18. Oxidative stress and Parkinson’s disease

    PubMed Central

    Blesa, Javier; Trigo-Damas, Ines; Quiroga-Varela, Anna; Jackson-Lewis, Vernice R.

    2015-01-01

    Parkinson disease (PD) is a chronic, progressive neurological disease that is associated with a loss of dopaminergic neurons in the substantia nigra pars compacta 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 PD. Environmental factors, such as neurotoxins, pesticides, insecticides, dopamine (DA) itself, and genetic mutations in PD-associated 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. PMID:26217195

  19. Saline stress enhanced accumulation of leaf phenolics in honeysuckle (Lonicera japonica Thunb.) without induction of oxidative stress.

    PubMed

    Yan, Kun; Zhao, Shijie; Bian, Lanxing; Chen, Xiaobing

    2017-03-01

    Honeysuckle (Lonicera japonica Thunb.) is a traditional medicinal plant in Chinese, and chlorogenic acid and luteolosid are its specific bioactive phenolic compounds. This study was to investigate leaf antioxidant responses in honeysuckle to saline stress with emphasis on phenolics through hydroponic experiments and field trials. NaCl stress did not stimulate antioxidant system including superoxide dismutase, ascorbate peroxidase, catalase and ascorbate, and had no significant effect on lipid peroxidation in the leaves. Consistently, no inhibition on photochemical capacity of photosystems suggested that reactive oxygen species (ROS) was maintained at a normal level under NaCl stress. However, leaf phenolic synthesis was activated by NaCl stress, indicated by elevated genes transcription and activity of phenylalanine ammonia-lyase and increased phenolics concentration. Specifically, leaf chlorogenic acid concentration was increased by 67.43% and 48.86% after 15 days of 150 and 300 mM NaCl stress, and the increase of luteolosid concentration was 54.26% and 39.74%. The accumulated phenolics hardly helped detoxify ROS in vivo in absence of oxidative stress, but the elevated phenolic synthesis might restrict ROS generation by consuming reduction equivalents. As with NaCl stress, soil salinity also increased concentrations of leaf phenolics including chlorogenic acid and luteolosid without exacerbated lipid peroxidation. In conclusion, leaf phenolics accumulation is a mechanism for the acclimation to saline stress probably by preventing oxidative stress in honeysuckle; leaf medicinal quality of honeysuckle can be improved by saline stress due to the accumulation of bioactive phenolic compounds.

  20. Oxidative stress and male reproductive health

    PubMed Central

    Aitken, Robert J; Smith, Tegan B; Jobling, Matthew S; Baker, Mark A; De Iuliis, Geoffry N

    2014-01-01

    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 conceived in vitro and serves as a driver for current research into the origins of free radical generation in the germ line. PMID:24369131

  1. Lamins as mediators of oxidative stress

    SciTech Connect

    Sieprath, Tom; Darwiche, Rabih; De Vos, Winnok H.

    2012-05-18

    Highlights: Black-Right-Pointing-Pointer The nuclear lamina defines structural and functional properties of the cell nucleus. Black-Right-Pointing-Pointer Lamina dysfunction leads to a broad spectrum of laminopathies. Black-Right-Pointing-Pointer Recent data is reviewed connecting laminopathies to oxidative stress. Black-Right-Pointing-Pointer A framework is proposed to explain interactions between lamins and oxidative stress. -- Abstract: The nuclear lamina defines both structural and functional properties of the eukaryotic cell nucleus. Mutations in the LMNA gene, encoding A-type lamins, lead to a broad spectrum of diseases termed laminopathies. While different hypotheses have been postulated to explain disease development, there is still no unified view on the mechanistic basis of laminopathies. Recent observations indicate that laminopathies are often accompanied by altered levels of reactive oxygen species and a higher susceptibility to oxidative stress at the cellular level. In this review, we highlight the role of reactive oxygen species for cell function and disease development in the context of laminopathies and present a framework of non-exclusive mechanisms to explain the reciprocal interactions between a dysfunctional lamina and altered redox homeostasis.

  2. Oxidative Stress in Patients With Acne Vulgaris

    PubMed Central

    Arican, Ozer; Belge Kurutas, Ergul; Sasmaz, Sezai

    2005-01-01

    Acne vulgaris is one of the common dermatological diseases and its pathogenesis is multifactorial. In this study, we aim to determine the effects of oxidative stress in acne vulgaris. Forty-three consecutive acne patients and 46 controls were enrolled. The parameters of oxidative stress such as catalase (CAT), glucose-6-phosphate dehydrogenase (G6PD), superoxide dismutase (SOD), and malondialdehyde (MDA) in the venous blood of cases were measured spectrophotometrically. The values compared with control group, the relation between the severity and distribution of acne, and the correlation of each enzyme level were researched. CAT and G6PD levels in patients were found to be statistically decreased, and SOD and MDA levels were found to be statistically increased (P < .001). However, any statistical difference and correlation could not be found between the severity and distribution of lesions and the mean levels of enzymes. In addition, we found that each enzyme is correlated with one another. Our findings show that oxidative stress exists in the acne patients. It will be useful to apply at least one antioxidant featured drug along with the combined acne treatment. PMID:16489259

  3. Chrononutrition against Oxidative Stress in Aging

    PubMed Central

    Garrido, M.; Terrón, M. P.; Rodríguez, A. B.

    2013-01-01

    Free radicals and oxidative stress have been recognized as important factors in the biology of aging and in many age-associated degenerative diseases. Antioxidant systems deteriorate during aging. It is, thus, considered that one way to reduce the rate of aging and the risk of chronic disease is to avoid the formation of free radicals and reduce oxidative stress by strengthening antioxidant defences. Phytochemicals present in fruits, vegetables, grains, and other foodstuffs have been linked to reducing the risk of major oxidative stress-induced diseases. Some dietary components of foods possess biological activities which influence circadian rhythms in humans. Chrononutrition studies have shown that not only the content of food, but also the time of ingestion contributes to the natural functioning of the circadian system. Dietary interventions with antioxidant-enriched foods taking into account the principles of chrononutrition are of particular interest for the elderly since they may help amplify the already powerful benefits of phytochemicals as natural instruments with which to prevent or delay the onset of common age-related diseases. PMID:23861994

  4. Oxidative stress and modification of synaptic proteins in hippocampus after traumatic brain injury.

    PubMed

    Ansari, Mubeen A; Roberts, Kelly N; Scheff, Stephen W

    2008-08-15

    Oxidative stress, an imbalance between oxidants and antioxidants, contributes to the pathogenesis of traumatic brain injury (TBI). Oxidative neurodegeneration is a key mediator of exacerbated morphological responses and deficits in behavioral recoveries. The present study assessed early hippocampal sequential imbalance to possibly enhance antioxidant therapy. Young adult male Sprague-Dawley rats were subjected to a unilateral moderate cortical contusion. At various times post-TBI, animals were killed and the hippocampus was analyzed for antioxidants (GSH, GSSG, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, glucose-6-phosphate dehydrogenase, superoxide dismutase, and catalase) and oxidants (acrolein, 4-hydroxynonenal, protein carbonyl, and 3-nitrotyrosine). Synaptic markers (synapsin I, postsynaptic density protein 95, synapse-associated protein 97, growth-associated protein 43) were also analyzed. All values were compared with those for sham-operated animals. Significant time-dependent changes in antioxidants were observed as early as 3 h posttrauma and paralleled increases in oxidants (4-hydroxynonenal, acrolein, and protein carbonyl), with peak values obtained at 24-48 h. Time-dependent changes in synaptic proteins (synapsin I, postsynaptic density protein 95, and synapse-associated protein 97) occurred well after levels of oxidants peaked. These results indicate that depletion of antioxidant systems following trauma could adversely affect synaptic function and plasticity. Early onset of oxidative stress suggests that the initial therapeutic window following TBI appears to be relatively short, and it may be necessary to stagger selective types of antioxidant therapy to target specific oxidative components.

  5. Neuro-oxidative-nitrosative stress in sepsis.

    PubMed

    Berg, Ronan M G; Møller, Kirsten; Bailey, Damian M

    2011-07-01

    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 brain parenchyma, due to failure of the local antioxidant systems. ROS/RNS cause structural membrane damage, induce inflammation, and scavenge nitric oxide (NO) to yield peroxynitrite (ONOO(-)). This activates the inducible NO synthase, which further compounds ONOO(-) formation. ROS/RNS cause mitochondrial dysfunction by inhibiting the mitochondrial electron transport chain and uncoupling oxidative phosphorylation, which ultimately leads to neuronal bioenergetic failure. Furthermore, in certain 'at risk' areas of the brain, free radicals may induce neuronal apoptosis. In the present review, we define a role for ROS/RNS-mediated neuronal bioenergetic failure and apoptosis as a primary mechanism underlying sepsis-associated encephalopathy and, in sepsis survivors, permanent cognitive deficits.

  6. Antibacterial activity of graphite, graphite oxide, graphene oxide, and reduced graphene oxide: membrane and oxidative stress.

    PubMed

    Liu, Shaobin; Zeng, Tingying Helen; Hofmann, Mario; Burcombe, Ehdi; Wei, Jun; Jiang, Rongrong; Kong, Jing; Chen, Yuan

    2011-09-27

    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.

  7. Attenuation of oxidative stress and cardioprotective effects of zinc supplementation in experimental diabetic rats.

    PubMed

    Barman, Susmita; Srinivasan, Krishnapura

    2017-02-01

    Oxidative stress plays a major role in the pathogenesis of diabetes mellitus, which further exacerbates damage of cardiac, hepatic and other tissues. We have recently reported that Zn supplementation beneficially modulates hyperglycaemia and hypoinsulinaemia, with attendant reduction of associated metabolic abnormalities in diabetic rats. The present study assessed the potential of Zn supplementation in modulating oxidative stress and cardioprotective effects in diabetic rats. Diabetes was induced in Wistar rats with streptozotocin, and groups of diabetic rats were treated with 5- and 10-fold dietary Zn interventions (0·19 and 0·38 g Zn/kg diet) for 6 weeks. The markers of oxidative stress, antioxidant enzyme activities and concentrations of antioxidant molecules, lipid profile, and expressions of fibrosis and pro-apoptotic factors in the cardiac tissue were particularly assessed. Supplemental Zn showed significant attenuation of diabetes-induced oxidative stress in terms of altered antioxidant enzyme activities and increased the concentrations of antioxidant molecules. Hypercholesterolaemia and hyperlipidaemia were also significantly countered by Zn supplementation. Along with attenuated oxidative stress, Zn supplementation also showed significant cardioprotective effects by altering the mRNA expressions of fibrosis and pro-apoptotic factors (by >50 %). The expression of lipid oxidative marker 4-hydroxy-2-nonenal (4-HNE) protein in cardiac tissue of diabetic animals was rectified (68 %) by Zn supplementation. Elevated cardiac and hepatic markers in circulation and pathological abnormalities in cardiac and hepatic tissue architecture of diabetic animals were ameliorated by dietary Zn intervention. The present study indicates that Zn supplementation can attenuate diabetes-induced oxidative stress in circulation as well as in cardiac and hepatic tissues.

  8. Short-term modern life-like stress exacerbates Aβ-pathology and synapse loss in 3xTg-AD mice

    PubMed Central

    Baglietto-Vargas, David; Chen, Yuncai; Suh, Dongjin; Ager, Rahasson R.; Rodriguez-Ortiz, Carlos J.; Mederios, Rodrigo; Myczek, Kristoffer; Green, Kim N.; Baram, Tallie Z.; LaFerla, Frank M.

    2016-01-01

    Alzheimer’s disease (AD) is a progressive neurological disorder that impairs memory and other cognitive functions in the elderly. The social and financial impacts of AD are overwhelming and are escalating exponentially as a result of population aging. Therefore, identifying AD-related risk factors and the development of more efficacious therapeutic approaches are critical to cure this neurological disorder. Current epidemiological evidence indicates that life experiences, including chronic stress, are a risk for AD. However, it is unknown if short-term stress, lasting for hours, influences the onset or progression of AD. Here, we determined the effect of short-term, multi-modal ‘modern life-like’ stress on AD pathogenesis and synaptic plasticity in mice bearing three AD mutations (the 3xTg-AD mouse model). We found that combined emotional and physical stress lasting 5 h severely impaired memory in wild-type mice and tended to impact it in already low-performing 3xTg-AD mice. This stress reduced the number of synapse-bearing dendritic spines in 3xTg-AD mice and increased Aβ levels by augmenting AβPP processing. Thus, short-term stress simulating modern-life conditions may exacerbate cognitive deficits in preclinical AD by accelerating amyloid pathology and reducing synapse numbers. PMID:26077803

  9. Oxidative Stress and Autophagy in Cardiovascular Homeostasis

    PubMed Central

    Morales, Cyndi R.; Pedrozo, Zully; Lavandero, Sergio

    2014-01-01

    Abstract Significance: Autophagy is an evolutionarily ancient process of intracellular protein and organelle recycling required to maintain cellular homeostasis in the face of a wide variety of stresses. Dysregulation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) leads to oxidative damage. Both autophagy and ROS/RNS serve pathological or adaptive roles within cardiomyocytes, depending on the context. Recent Advances: ROS/RNS and autophagy communicate with each other via both transcriptional and post-translational events. This cross talk, in turn, regulates the structural integrity of cardiomyocytes, promotes proteostasis, and reduces inflammation, events critical to disease pathogenesis. Critical Issues: Dysregulation of either autophagy or redox state has been implicated in many cardiovascular diseases. Cardiomyocytes are rich in mitochondria, which make them particularly sensitive to oxidative damage. Maintenance of mitochondrial homeostasis and elimination of defective mitochondria are each critical to the maintenance of redox homeostasis. Future Directions: The complex interplay between autophagy and oxidative stress underlies a wide range of physiological and pathological events and its elucidation holds promise of potential clinical applicability. Antioxid. Redox Signal. 20, 507–518. PMID:23641894

  10. Oxidative stress, thyroid dysfunction & Down syndrome

    PubMed Central

    Campos, Carlos; Casado, Ángela

    2015-01-01

    Down syndrome (DS) is one of the most common chromosomal disorders, occurring in one out of 700-1000 live births, and the most common cause of mental retardation. Thyroid dysfunction is the most typical endocrine abnormality in patients with DS. It is well known that thyroid dysfunction is highly prevalent in children and adults with DS and that both hypothyroidism and hyperthyroidism are more common in patients with DS than in the general population. Increasing evidence has shown that DS individuals are under unusual increased oxidative stress, which may be involved in the higher prevalence and severity of a number of pathologies associated with the syndrome, as well as the accelerated ageing observed in these individuals. The gene for Cu/Zn superoxide dismutase (SOD1) is coded on chromosome 21 and it is overexpressed (~50%) resulting in an increase of reactive oxygen species (ROS) due to overproduction of hydrogen peroxide (H2O2). ROS leads to oxidative damage of DNA, proteins and lipids, therefore, oxidative stress may play an important role in the pathogenesis of DS. PMID:26354208

  11. Beyond Diabetes: Does Obesity-Induced Oxidative Stress Drive the Aging Process?

    PubMed Central

    Salmon, Adam B.

    2016-01-01

    Despite numerous correlative data, a causative role for oxidative stress in mammalian longevity has remained elusive. However, there is strong evidence that increased oxidative stress is associated with exacerbation of many diseases and pathologies that are also strongly related to advanced age. Obesity, or increased fat accumulation, is one of the most common chronic conditions worldwide and is associated with not only metabolic dysfunction but also increased levels of oxidative stress in vivo. Moreover, obesity is also associated with significantly increased risks of cardiovascular disease, neurological decline and cancer among many other diseases as well as a significantly increased risk of mortality. In this review, we investigate the possible interpretation that the increased incidence of these diseases in obesity may be due to chronic oxidative stress mediating segmental acceleration of the aging process. Understanding how obesity can alter cellular physiology beyond that directly related to metabolic function could open new therapeutic areas of approach to extend the period of healthy aging among people of all body composition. PMID:27438860

  12. Dietary curcumin counteracts the outcome of traumatic brain injury on oxidative stress, synaptic plasticity, and cognition.

    PubMed

    Wu, Aiguo; Ying, Zhe; Gomez-Pinilla, Fernando

    2006-02-01

    The pervasive action of oxidative stress on neuronal function and plasticity after traumatic brain injury (TBI) is becoming increasingly recognized. Here, we evaluated the capacity of the powerful antioxidant curry spice curcumin ingested in the diet to counteract the oxidative damage encountered in the injured brain. In addition, we have examined the possibility that dietary curcumin may favor the injured brain by interacting with molecular mechanisms that maintain synaptic plasticity and cognition. The analysis was focused on the BDNF system based on its action on synaptic plasticity and cognition by modulating synapsin I and CREB. Rats were exposed to a regular diet or a diet high in saturated fat, with or without 500 ppm curcumin for 4 weeks (n = 8/group), before a mild fluid percussion injury (FPI) was performed. The high-fat diet has been shown to exacerbate the effects of TBI on synaptic plasticity and cognitive function. Supplementation of curcumin in the diet dramatically reduced oxidative damage and normalized levels of BDNF, synapsin I, and CREB that had been altered after TBI. Furthermore, curcumin supplementation counteracted the cognitive impairment caused by TBI. These results are in agreement with previous evidence, showing that oxidative stress can affect the injured brain by acting through the BDNF system to affect synaptic plasticity and cognition. The fact that oxidative stress is an intrinsic component of the neurological sequel of TBI and other insults indicates that dietary antioxidant therapy is a realistic approach to promote protective mechanisms in the injured brain.

  13. Flavonoids and oxidative stress in Drosophila melanogaster.

    PubMed

    Sotibrán, América Nitxin Castañeda; Ordaz-Téllez, María Guadalupe; Rodríguez-Arnaiz, Rosario

    2011-11-27

    Flavonoids are a family of antioxidants that are widely represented in fruits, vegetables, dry legumes, and chocolate, as well as in popular beverages, such as red wine, coffee, and tea. The flavonoids chlorogenic acid, kaempferol, quercetin and quercetin 3β-d-glycoside were investigated for genotoxicity using the wing somatic mutation and recombination test (SMART). This test makes use of two recessive wing cell markers: multiple wing hairs (mwh) and flare (flr(3)), which are mutations located on the left arm of chromosome 3 of Drosophila melanogaster and are indicative of both mitotic recombination and various types of mutational events. In order to test the antioxidant capacities of the flavonoids, experiments were conducted with various combinations of oxidants and polyphenols. Oxidative stress was induced using hydrogen peroxide, the Fenton reaction and paraquat. Third-instar transheterozygous larvae were chronically treated for all experiments. The data obtained in this study showed that, at the concentrations tested, the flavonoids did not induce somatic mutations or recombination in D. melanogaster with the exception of quercetin, which proved to be genotoxic at only one concentration. The oxidants hydrogen peroxide and the Fenton reaction did not induce mutations in the wing somatic assay of D. melanogaster, while paraquat and combinations of flavonoids produced significant numbers of small single spots. Quercetin 3β-d-glycoside mixed with paraquat was shown to be desmutagenic. Combinations of the oxidants with the other flavonoids did not show any antioxidant activity.

  14. Oxidative stress and antioxidants: Distress or eustress?

    PubMed

    Niki, Etsuo

    2016-04-01

    There is a growing consensus that reactive oxygen species (ROS) are not just associated with various pathologies, but that they act as physiological redox signaling messenger with important regulatory functions. It is sometimes stated that "if ROS is a physiological signaling messenger, then removal of ROS by antioxidants such as vitamins E and C may not be good for human health." However, it should be noted that ROS acting as physiological signaling messenger and ROS removed by antioxidants are not the same. The lipid peroxidation products of polyunsaturated fatty acids and cholesterol induce adaptive response and enhance defense capacity against subsequent oxidative insults, but it is unlikely that these lipid peroxidation products are physiological signaling messenger produced on purpose. The removal of ROS and inhibition of lipid peroxidation by antioxidants should be beneficial for human health, although it has to be noted also that they may not be an effective inhibitor of oxidative damage mediated by non-radical oxidants. The term ROS is vague and, as there are many ROS and antioxidants which are different in chemistry, it is imperative to explicitly specify ROS and antioxidant to understand the effects and role of oxidative stress and antioxidants properly.

  15. Biocompatibility of implantable materials: An oxidative stress viewpoint.

    PubMed

    Mouthuy, Pierre-Alexis; Snelling, Sarah J B; Dakin, Stephanie G; Milković, Lidija; Gašparović, Ana Čipak; Carr, Andrew J; Žarković, Neven

    2016-12-01

    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.

  16. Air pollution and circulating biomarkers of oxidative stress

    PubMed Central

    Staimer, Norbert; Vaziri, Nosratola D.

    2013-01-01

    Chemical components of air pollutant exposures that induce oxidative stress and subsequent inflammation may be partly responsible for associations of cardiovascular morbidity and mortality with airborne particulate matter and combustion-related pollutant gasses. However, epidemiologic evidence regarding this is limited. An exposure-assessment approach is to measure the oxidative potential of particle mixtures because it is likely that hundreds of correlated chemicals are involved in overall effects of air pollution on health. Oxidative potential likely depends on particle composition and size distribution, especially ultrafine particle concentration, and on transition metals and certain semivolatile and volatile organic chemicals. For health effects, measuring systemic oxidative stress in the blood is one feasible approach, but there is no universal biomarker of oxidative stress and there are many potential target molecules (lipids, proteins, DNA, nitric oxide, etc.), which may be more or less suitable for specific study goals. Concurrent with the measurement of oxidative stress, it is important to measure gene and/or protein expression of endogenous antioxidant enzymes because they can modify relations between oxidative stress biomarkers and air pollutants. Conversely, the expression and activities of these enzymes are modified by oxidative stress. This interplay will likely determine the observed effects of air pollutants on systemic inflammatory and thrombotic mediators and related clinical outcomes. Studies are needed to assess the reliability and validity of oxidative stress biomarkers, evaluate differences in associations between oxidative stress biomarkers and various pollutant measurements (mass, chemical components, and oxidative potential), and evaluate impacts of antioxidant responses on these relations. PMID:23626660

  17. Correlates of oxidative stress in wild kestrel nestlings (Falco tinnunculus).

    PubMed

    Costantini, David; Casagrande, Stefania; De Filippis, Stefania; Brambilla, Gianfranco; Fanfani, Alberto; Tagliavini, James; Dell'Omo, Giacomo

    2006-05-01

    The fitness of an organism can be affected by conditions experienced during early development. In light of the impact that oxidative stress can have on the health and ageing of a bird species, this study evaluated factors accounting for the variation in oxidative stress levels in nestlings of the Eurasian kestrel (Falco tinnunculus) by measuring the serum concentration of reactive oxygen metabolites and the serum antioxidant barrier against hypochlorite-induced oxidation. The ratio between these two variables was considered as an index of oxidative stress, with higher values meaning higher oxidative damage. Six-chick broods showed the highest level of oxidative stress, while no effect of sex was found. Age showed an inverse relationship with the oxidants and the levels of oxidative stress, with younger birds having higher levels. Hatching date, body condition, body mass and carotenoid concentration did not show any relationship with oxidants, antioxidants or degree of oxidative stress. These findings suggest that intrabrood sibling competition could play a role in determining oxidative stress, and that in carnivorous birds other antioxidant molecules could be more important than carotenoids to reduce oxidative stress.

  18. Novel insights into the aetiology and pathophysiology of increased airway inflammation during COPD exacerbations.

    PubMed

    Tsoumakidou, Maria; Siafakas, Nikolaos M

    2006-05-22

    Airway inflammation increases during acute exacerbations of COPD. Extrinsic factors, such as airway infections, increased air pollution, and intrinsic factors, such as increased oxidative stress and altered immunity may contribute to this increase. The evidence for this and the potential mechanisms by which various aetiological agents increase inflammation during COPD exacerbations is reviewed. The pathophysiologic consequences of increased airway inflammation during COPD exacerbations are also discussed. This review aims to establish a cause and effect relationship between etiological factors of increased airway inflammation and COPD exacerbations based on recently published data. Although it can be speculated that reducing inflammation may prevent and/or treat COPD exacerbations, the existing anti-inflammatory treatments are modestly effective.

  19. PHEOCHROMOCYTOMA: A CATECHOLAMINE AND OXIDATIVE STRESS DISORDER

    PubMed Central

    Pacak, Karel

    2012-01-01

    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

  20. Oxidative stress in severe pulmonary trauma in critical ill patients. Antioxidant therapy in patients with multiple trauma--a review.

    PubMed

    Bedreag, Ovidiu Horea; Rogobete, Alexandru Florin; Sarandan, Mirela; Cradigati, Alina Carmen; Papurica, Marius; Dumbuleu, Maria Corina; Chira, Alexandru Mihai; Rosu, Oana Maria; Sandesc, Dorel

    2015-01-01

    Multiple trauma patients require extremely good management and thus, the trauma team needs to be prepared and to be up to date with the new standards of intensive therapy. Oxidative stress and free radicals represent an extremely aggressive factor to cells, having a direct consequence upon the severity of lung inflammation. Pulmonary tissue is damaged by oxidative stress, leading to biosynthesis of mediators that exacerbate inflammation modulators. The subsequent inflammation spreads throughout the body, leading most of the time to multiple organ dysfunction and death. In this paper, we briefly present an update of biochemical effects of oxidative stress and free radical damage to the pulmonary tissue in patients in critical condition in the intensive care unit. Also, we would like to present a series of active substances that substantially reduce the aggressiveness of free radicals, increasing the chances of survival.

  1. Oxidative stress: Biomarkers and novel therapeutic pathways.

    PubMed

    Maiese, Kenneth; Chong, Zhao Zhong; Hou, Jinling; Shang, Yan Chen

    2010-03-01

    Oxidative stress significantly impacts multiple cellular pathways that can lead to the initiation and progression of varied disorders throughout the body. It therefore becomes imperative to elucidate the components and function of novel therapeutic strategies against oxidative stress to further clinical diagnosis and care. In particular, both the growth factor and cytokine erythropoietin (EPO) and members of the mammalian forkhead transcription factors of the O class (FoxOs) may offer the greatest promise for new treatment regimens since these agents and the cellular pathways they oversee cover a range of critical functions that directly influence progenitor cell development, cell survival and degeneration, metabolism, immune function, and cancer cell invasion. Furthermore, both EPO and FoxOs function not only as therapeutic targets, but also as biomarkers of disease onset and progression, since their cellular pathways are closely linked and overlap with several unique signal transduction pathways. However, biological outcome with EPO and FoxOs may sometimes be both unexpected and undesirable that can raise caution for these agents and warrant further investigations. Here we present the exciting as well as complicated role EPO and FoxOs possess to uncover the benefits as well as the risks of these agents for cell biology and clinical care in processes that range from stem cell development to uncontrolled cellular proliferation.

  2. OXIDATIVE STRESS: BIOMARKERS AND NOVEL THERAPEUTIC PATHWAYS

    PubMed Central

    Maiese, Kenneth; Chong, Zhao Zhong; Hou, Jinling; Shang, Yan Chen

    2010-01-01

    Oxidative stress significantly impacts multiple cellular pathways that can lead to the initiation and progression of varied disorders throughout the body. It therefore becomes imperative to elucidate the components and function of novel therapeutic strategies against oxidative stress to further clinical diagnosis and care. In particular, both the growth factor and cytokine erythropoietin (EPO) and members of the mammalian forkhead transcription factors of the O class (FoxOs) may offer the greatest promise for new treatment regimens since these agents and the cellular pathways they oversee cover a range of critical functions that directly influence progenitor cell development, cell survival and degeneration, metabolism, immune function, and cancer cell invasion. Furthermore, both EPO and FoxOs function not only as therapeutic targets, but also as biomarkers of disease onset and progression, since their cellular pathways are closely linked and overlap with several unique signal transduction pathways. However, biological outcome with EPO and FoxOs may sometimes be both unexpected and undesirable that can raise caution for these agents and warrant further investigations. Here we present the exciting as well as complicated role EPO and FoxOs possess to uncover the benefits as well as the risks of these agents for cell biology and clinical care in processes that range from stem cell development to uncontrolled cellular proliferation. PMID:20064603

  3. Oxidative Stress in Genetic Mouse Models of Parkinson's Disease

    PubMed Central

    Varçin, Mustafa; Bentea, Eduard; Michotte, Yvette; Sarre, Sophie

    2012-01-01

    There is extensive evidence in Parkinson's disease of a link between oxidative stress and some of the monogenically inherited Parkinson's disease-associated genes. This paper focuses on the importance of this link and potential impact on neuronal function. Basic mechanisms of oxidative stress, the cellular antioxidant machinery, and the main sources of cellular oxidative stress are reviewed. Moreover, attention is given to the complex interaction between oxidative stress and other prominent pathogenic pathways in Parkinson's disease, such as mitochondrial dysfunction and neuroinflammation. Furthermore, an overview of the existing genetic mouse models of Parkinson's disease is given and the evidence of oxidative stress in these models highlighted. Taken into consideration the importance of ageing and environmental factors as a risk for developing Parkinson's disease, gene-environment interactions in genetically engineered mouse models of Parkinson's disease are also discussed, highlighting the role of oxidative damage in the interplay between genetic makeup, environmental stress, and ageing in Parkinson's disease. PMID:22829959

  4. Chasing great paths of Helmut Sies "Oxidative Stress".

    PubMed

    Majima, Hideyuki J; Indo, Hiroko P; Nakanishi, Ikuo; Suenaga, Shigeaki; Matsumoto, Ken-Ichiro; Matsui, Hirofumi; Minamiyama, Yukiko; Ichikawa, Hiroshi; Yen, Hsiu-Chuan; Hawkins, Clare L; Davies, Michael J; Ozawa, Toshihiko; St Clair, Daret K

    2016-04-01

    Prof. Dr. Helmut Sies is a pioneer of "Oxidative Stress", and has published over 18 papers with the name of "Oxidative Stress" in the title. He has been Editor-in-Chief of the journal "Archives of Biochemistry and Biophysics" for many years, and is a former Editor-in-Chief of the journal "Free Radical Research". He has clarified our understanding of the causes of chronic developing diseases, and has studied antioxidant factors. In this article, importance of "Oxidative Stress" and our mitochondrial oxidative stress studies; roles of mitochondrial ROS, effects of vitamin E and its homologues in oxidative stress-related diseases, effects of antioxidants in vivo and in vitro, and a mitochondrial superoxide theory for oxidative stress diseases and aging are introduced, and some of our interactions with Helmut are described, congratulating and appreciating his great path.

  5. A Nucleocytoplasmic Shuttling Protein in Oxidative Stress Tolerance

    SciTech Connect

    Ow, David W.; Song, Wen

    2003-03-26

    Plants for effective extraction of toxic metals and radionuclides must tolerate oxidative stress. To identify genes that enhance oxidative stress tolerance, an S. pombe cDNA expression plasmid library was screened for the ability to yield hypertolerant colonies. Here, we report on the properties of one gene that confers hypertolerance to cadmium and oxidizing chemicals. This gene appears to be conserved in other organisms as homologous genes are found in human, mouse, fruitfly and Arabidopsis. The fruitfly and Arabidopsis genes likewise enhance oxidative stress tolerance in fission yeast. During oxidative stress, the amount of mRNA does not change, but protein fusions to GFP relocate from the cytoplasm to the nucleus. The same pattern is observed with the Arabidopsis homologue-GFP fusion protein. This behavior suggests a signaling role in oxidative stress tolerance and these conserved proteins may be targets for engineering stress tolerant plants for phytoremediation.

  6. Oxidative stress induction by nanoparticles in THP-1 cells with 4-HNE production: stress biomarker or oxidative stress signalling molecule?

    PubMed

    Foucaud, L; Goulaouic, S; Bennasroune, A; Laval-Gilly, P; Brown, D; Stone, V; Falla, J

    2010-09-01

    The aim of this study was to investigate whether carbon black (CB) nanoparticles might induce toxicity to monocytic cells in vitro via an oxidative stress mechanism involving formation of the lipid peroxidation product 4-hydroxynonenal (4-HNE) and the subsequent role of 4-HNE in inducing further cytotoxic effects. ROS production in cells by CB nanoparticles was shown by the oxidation of DCFH after a short time exposure. These particles induced the formation of 4-HNE-protein adducts and significant modification of glutathione content corresponding to an increase of oxidized glutathione form (GSSG) and a decrease of total glutathione (GSX) content. These results attest to an oxidative stress induced by the carbon black nanoparticles, although no induction of HO-1 protein expression was detected. Concerning the effects of a direct exposure to 4-HNE, our results showed that 4-HNE is not cytotoxic for concentrations lower than 12.5 microM. By contrast, it provokes a very high cytotoxicity for concentrations above 25 microM. An induction of HO-1 expression was observed from concentrations above 5 microM of 4-HNE. Finally, glutathione content decreased significantly from 5 microM of 4-HNE but no modification was observed under this concentration. The discrepancy between effects of carbon black nanoparticles and 4-HNE on the intracellular markers of oxidative stress suggests that 4-HNE is not directly implied in the signalling of oxidative toxicity of nanoparticles but is an effective biomarker of oxidative effects of nanoparticles.

  7. Oxidative stress in marine environments: biochemistry and physiological ecology.

    PubMed

    Lesser, Michael P

    2006-01-01

    Oxidative stress-the production and accumulation of reduced oxygen intermediates such as superoxide radicals, singlet oxygen, hydrogen peroxide, and hydroxyl radicals-can damage lipids, proteins, and DNA. Many disease processes of clinical interest and the aging process involve oxidative stress in their underlying etiology. The production of reactive oxygen species is also prevalent in the world's oceans, and oxidative stress is an important component of the stress response in marine organisms exposed to a variety of insults as a result of changes in environmental conditions such as thermal stress, exposure to ultraviolet radiation, or exposure to pollution. As in the clinical setting, reactive oxygen species are also important signal transduction molecules and mediators of damage in cellular processes, such as apoptosis and cell necrosis, for marine organisms. This review brings together the voluminous literature on the biochemistry and physiology of oxidative stress from the clinical and plant physiology disciplines with the fast-increasing interest in oxidative stress in marine environments.

  8. Diabetes and the Brain: Oxidative Stress, Inflammation, and Autophagy

    PubMed Central

    Muriach, María; Flores-Bellver, Miguel; Romero, Francisco J.; Barcia, Jorge M.

    2014-01-01

    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. PMID:25215171

  9. Diabetes and the brain: oxidative stress, inflammation, and autophagy.

    PubMed

    Muriach, María; Flores-Bellver, Miguel; Romero, Francisco J; Barcia, Jorge M

    2014-01-01

    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.

  10. Nrf2 protects photoreceptor cells from photo-oxidative stress induced by blue light.

    PubMed

    Chen, Wan-Ju; Wu, Caiying; Xu, Zhenhua; Kuse, Yoshiki; Hara, Hideaki; Duh, Elia J

    2017-01-01

    Oxidative stress plays a key role in age-related macular degeneration and hereditary retinal degenerations. Light damage in rodents has been used extensively to model oxidative stress-induced photoreceptor degeneration, and photo-oxidative injury from blue light is particularly damaging to photoreceptors. The endogenous factors protecting photoreceptors from oxidative stress, including photo-oxidative stress, are continuing to be elucidated. In this study, we evaluated the effect of blue light exposure on photoreceptors and its relationship to Nrf2 using cultured murine photoreceptor (661W) cells. 661W cells were exposed to blue light at 2500 lux. Exposure to blue light for 6-24 h resulted in a significant increase in intracellular reactive oxygen species (ROS) and death of 661W cells in a time-dependent fashion. Blue light exposure resulted in activation of Nrf2, as indicated by an increase in nuclear translocation of Nrf2. This was associated with a significant induction of expression of Nrf2 as well as an array of Nrf2 target genes, including antioxidant genes, as indicated by quantitative reverse transcription PCR (qRT-PCR). In order to determine the functional role of Nrf2, siRNA-mediated knockdown studies were performed. Nrf2-knockdown in 661W cells resulted in significant exacerbation of blue light-induced reactive oxygen species levels as well as cell death. Taken together, these findings indicate that Nrf2 is an important endogenous protective factor against oxidative stress in photoreceptor cells. This suggests that drugs targeting Nrf2 could be considered as a neuroprotective strategy for photoreceptors in AMD and other retinal conditions.

  11. Management of multicellular senescence and oxidative stress

    PubMed Central

    Haines, David D; Juhasz, Bela; Tosaki, Arpad

    2013-01-01

    Progressively sophisticated understanding of cellular and molecular processes that contribute to age-related physical deterioration is being gained from ongoing research into cancer, chronic inflammatory syndromes and other serious disorders that increase with age. Particularly valuable insight has resulted from characterization of how senescent cells affect the tissues in which they form in ways that decrease an organism's overall viability. Increasingly, the underlying pathophysiology of ageing is recognized as a consequence of oxidative damage. This leads to hyperactivity of cell growth pathways, prominently including mTOR (mammalian target of rapamycin), that contribute to a build-up in cells of toxic aggregates such as progerin (a mutant nuclear cytoskeletal protein), lipofuscin and other cellular debris, triggering formation of senescent cellular phenotypes, which interact destructively with surrounding tissue. Indeed, senescent cell ablation dramatically inhibits physical deterioration in progeroid (age-accelerated) mice. This review explores ways in which oxidative stress creates ageing-associated cellular damage and triggers induction of the cell death/survival programs’ apoptosis, necrosis, autophagy and ‘necroapoptophagy’. The concept of ‘necroapoptophagy’ is presented here as a strategy for varying tissue oxidative stress intensity in ways that induce differential activation of death versus survival programs, resulting in enhanced and sustained representation of healthy functional cells. These strategies are discussed in the context of specialized mesenchymal stromal cells with the potential to synergize with telocytes in stabilizing engrafted progenitor cells, thereby extending periods of healthy life. Information and concepts are summarized in a hypothetical approach to suppressing whole-organism senescence, with methods drawn from emerging understandings of ageing, gained from Cnidarians (jellyfish, corals and anemones) that undergo a

  12. Biomarkers of exposure to endogenous oxidative and aldehyde stress.

    PubMed

    Bruce, W Robert; Lee, Owen; Liu, Zhen; Marcon, Norman; Minkin, Salomon; O'Brien, Peter J

    2011-08-01

    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.

  13. Extract of Polygala tenuifolia Alleviates Stress-Exacerbated Atopy-Like Skin Dermatitis through the Modulation of Protein Kinase A and p38 Mitogen-Activated Protein Kinase Signaling Pathway

    PubMed Central

    Sur, Bongjun; Lee, Bombi; Yoon, Ye Seul; Lim, Pooreum; Hong, Riwon; Yeom, Mijung; Lee, Hyang Sook; Park, Hijoon; Shim, Insop; Lee, Hyejung; Jang, Young Pyo; Hahm, Dae-Hyun

    2017-01-01

    Atopic dermatitis (AD) and stress create a vicious cycle: stress exacerbates atopic symptoms, and atopic disease elicits stress and anxiety. Targeting multiple pathways including stress and allergic inflammation is, therefore, important for treating AD. In this study, we investigated the remedial value of Polygala tenuifolia Willd. (PTW) for treating immobilization (IMO) stress-exacerbated atopy-like skin dermatitis and its underlying mechanism. Trimellitic anhydride (TMA) was applied to dorsal skin for sensitization and subsequently both ears for eliciting T-cell-dependent contact hypersensitivity in mice, which underwent 2 h-IMO stress and PTW administration for the latter 6 and 9 days in the ear exposure period of TMA, respectively. To elicit in vitro degranulation of human mast cell line-1 (HMC-1), 10 µM substance P (SP) and 200 nM corticotrophin-releasing factor (CRF) were sequentially added with 48 h-interval. PTW extract (500 µg/mL) was added 30 min before CRF treatment. IMO stress exacerbated TMA-induced scratching behavior by 252%, and increased their blood corticosterone levels by two-fold. Treatment with 250 mg/kg PTW significantly restored IMO stress-exacerbated scratching behavior and other indicators such as skin inflammation and water content, lymph node weights, and serum histamine and immunoglobulin E (lgE) levels. Furthermore, it also reversed TMA-stimulated expression of tumor necrosis factor (TNF)-α and interleukin (IL)-4 mRNAs in ear tissues. PTW significantly inhibited SP/CRF-stimulated degranulation of HMC-1 cells, subsequent tryptase secretion, and protein kinase A (PKA) activity. PTW also selectively inhibited p38 mitogen-activated protein kinase (MAPK) phosphorylation in SP/CRF-treated HMC-1 cells. PTW significantly inhibited HMC-1 cell degranulation and alleviated IMO stress-exacerbated atopic dermatitis symptoms by modulating the PKA/p38 MAPK signaling pathway. PMID:28106783

  14. Oxidative and nitrosative stress in ammonia neurotoxicity.

    PubMed

    Skowrońska, Marta; Albrecht, Jan

    2013-04-01

    Increased ammonia accumulation in the brain due to liver dysfunction is a major contributor to the pathogenesis of hepatic encephalopathy (HE). Fatal outcome of rapidly progressing (acute) HE is mainly related to cytotoxic brain edema associated with astrocytic swelling. An increase of brain ammonia in experimental animals or treatment of cultured astrocytes with ammonia generates reactive oxygen and nitrogen species in the target tissues, leading to oxidative/nitrosative stress (ONS). In cultured astrocytes, ammonia-induced ONS is invariably associated with the increase of the astrocytic cell volume. Interrelated mechanisms underlying this response include increased nitric oxide (NO) synthesis which is partly coupled to the activation of NMDA receptors and increased generation of reactive oxygen species by NADPH oxidase. ONS and astrocytic swelling are further augmented by excessive synthesis of glutamine (Gln) which impairs mitochondrial function following its accumulation in there and degradation back to ammonia ("the Trojan horse" hypothesis). Ammonia also induces ONS in other cell types of the CNS: neurons, microglia and the brain capillary endothelial cells (BCEC). ONS in microglia contributes to the central inflammatory response, while its metabolic and pathophysiological consequences in the BCEC evolve to the vasogenic brain edema associated with HE. Ammonia-induced ONS results in the oxidation of mRNA and nitration/nitrosylation of proteins which impact intracellular metabolism and potentiate the neurotoxic effects. Simultaneously, ammonia facilitates the antioxidant response of the brain, by activating astrocytic transport and export of glutathione, in this way increasing the availability of precursors of neuronal glutathione synthesis.

  15. Alterations in magnesium and oxidative status during chronic emotional stress.

    PubMed

    Cernak, I; Savic, V; Kotur, J; Prokic, V; Kuljic, B; Grbovic, D; Veljovic, M

    2000-03-01

    Magnesium and oxidative status were investigated in young volunteers exposed to chronic stress (political intolerance, awareness of potential military attacks, permanent stand-by duty and reduced holidays more than 10 years) or subchronic stress consisting of everyday mortal danger in military actions lasting more than 3 months. Significant decreases in plasma ionized Mg2+, total Mg and ionized Ca2+ concentrations were found in both groups. Similarly, both study groups exhibited oxidative stress as assessed by increased plasma superoxide anions and malondialdehyde and modified antioxidant defense. There were no significant differences between the two stress groups. A negative correlation between magnesium balance and oxidative stress was observed suggesting that the same etiological factor (chronic stress) initiate decreases in both free and total magnesium concentrations and simultaneously increase oxidative stress intensity. These findings support the need for magnesium supplementation with antioxidant vitamins for people living in conditions of chronic stress.

  16. Endoplasmic Reticulum Stress Links Oxidative Stress to Impaired Pancreatic Beta-Cell Function Caused by Human Oxidized LDL

    PubMed Central

    Favre, Dimitri; Ezanno, Hélène; Bonnefond, Amélie; Bonner, Caroline; Gmyr, Valéry; Kerr-Conte, Julie; Gauthier, Benoit R.; Widmann, Christian; Waeber, Gérard; Pattou, François; Froguel, Philippe; Abderrahmani, Amar

    2016-01-01

    Elevated plasma concentration of the pro-atherogenic oxidized low density lipoprotein cholesterol (LDL) triggers adverse effects in pancreatic beta-cells and is associated with type 2 diabetes. Here, we investigated whether the endoplasmic reticulum (ER) stress is a key player coupling oxidative stress to beta-cell dysfunction and death elicited by human oxidized LDL. We found that human oxidized LDL activates ER stress as evidenced by the activation of the inositol requiring 1α, and the elevated expression of both DDIT3 (also called CHOP) and DNAJC3 (also called P58IPK) ER stress markers in isolated human islets and the mouse insulin secreting MIN6 cells. Silencing of Chop and inhibition of ER stress markers by the chemical chaperone phenyl butyric acid (PBA) prevented cell death caused by oxidized LDL. Finally, we found that oxidative stress accounts for activation of ER stress markers induced by oxidized LDL. Induction of Chop/CHOP and p58IPK/P58IPK by oxidized LDL was mimicked by hydrogen peroxide and was blocked by co-treatment with the N-acetylcystein antioxidant. As a conclusion, the harmful effects of oxidized LDL in beta-cells requires ER stress activation in a manner that involves oxidative stress. This mechanism may account for impaired beta-cell function in diabetes and can be reversed by antioxidant treatment. PMID:27636901

  17. Targeting oxidative stress response by green tea polyphenols: clinical implications.

    PubMed

    Yiannakopoulou, Eugenia Ch

    2013-09-01

    Green tea polyphenols, the most interesting constituent of green tea leaves, have been shown to have both pro-oxidant and antioxidant properties. Both pro-oxidant and antioxidant properties are expected to contribute to modulation of oxidative stress response under ideal optimal dosage regimens. Exposure to a low concentration of a pro-oxidant prior to exposure to oxidative stress induces the expression of genes that code for proteins that induce adaptation in a subsequent oxidative stress. On the other hand, exposure to an antioxidant concurrently with exposure to the oxidative stress affords protection through free radical scavenging or through other indirect antioxidant mechanisms. In any case, the optimal conditions that afford protection from oxidative stress should be defined for any substance with redox properties. Green tea polyphenols, being naturally occurring substances, seem to be an ideal option for the modulation of oxidative stress response. This paper reviews available data on the pro-oxidant and antioxidant properties of green tea polyphenols focusing on their potential on the modulation of oxidative stress response.

  18. Effects of oxidative stress on erythrocyte deformability

    NASA Astrophysics Data System (ADS)

    Bayer, Rainer; Wasser, Gerd

    1996-05-01

    Hemolysis as a consequence of open heart surgery is well investigated and explained by the oxidative and/or mechanical stress produced, e.g. by the heart lung machine. In Europe O3 is widely used by physicians, dedicated to alternative medicine. They apply O3 mostly by means of the Major Autohematotherapy (MAH, a process of removing 50 - 100 ml of blood, adding O3 gas to it and returning it to the patient's body). No controlled studies on the efficacy of O3 are available so far, but several anecdotal cases appear to confirm that MAH improves microcirculation, possibly due to increased RBC flexibility. Most methods established to estimate RBC deformability are hard to standardize and include high error of measurement. For our present investigation we used the method of laser diffraction in combination with image analysis. The variation coefficient of the measurement is less than 1%. Previous investigations of our group have shown, that mechanical stress decreases deformability, already at rather low levels of mechanical stress which do not include hemolysis. On the other hand exposure to O2, H2O2 or O3 does not alter the deformability of RBC and--except O3--does not induce considerably hemolysis. However this only holds true if deformability (shear rates 36/s - 2620/s) is determined in isotonic solutions. In hypertonic solutions O3 decreases RBC deformability, but improves it in hypotonic solutions. The results indicate that peroxidative stress dehydrates RBC and reduces their size. To explain the positive effect of O3 on the mechanical fragility of RBC we tentatively assume, that the reduction of RBC size facilitates the feed through small pore filters. In consequence, the size reduction in combination with undisturbed deformability at iso-osmolarity may have a beneficial effect on microcirculation.

  19. Effect of paraquat-induced oxidative stress

    PubMed Central

    Wiemer, Matthias; Osiewacz, Heinz D.

    2014-01-01

    Aging of biological systems is influenced by various factors, conditions and processes. Among others, processes allowing organisms to deal with various types of stress are of key importance. In particular, oxidative stress as the result of the generation of reactive oxygen species (ROS) at the mitochondrial respiratory chain and the accumulation of ROS-induced molecular damage has been strongly linked to aging. Here we view the impact of ROS from a different angle: their role in the control of gene expression. We report a genome-wide transcriptome analysis of the fungal aging model Podospora anserina grown on medium containing paraquat (PQ). This treatment leads to an increased cellular generation and release of H2O2, a reduced growth rate, and a decrease in lifespan. The combined challenge by PQ and copper has a synergistic negative effect on growth and lifespan. The data from the transcriptome analysis of the wild type cultivated under PQ-stress and their comparison to those of a longitudinal aging study as well as of a copper-uptake longevity mutant of P. anserina revealed that PQ-stress leads to the up-regulation of transcripts coding for components involved in mitochondrial remodeling. PQ also affects the expression of copper-regulated genes suggesting an increase of cytoplasmic copper levels as it has been demonstrated earlier to occur during aging of P. anserina and during senescence of human fibroblasts. This effect may result from the induction of the mitochondrial permeability transition pore via PQ-induced ROS, leading to programmed cell death as part of an evolutionary conserved mechanism involved in biological aging and lifespan control. PMID:28357247

  20. Oxidative stress is increased in C. elegans models of Huntington's disease but does not contribute to polyglutamine toxicity phenotypes.

    PubMed

    Machiela, Emily; Dues, Dylan J; Senchuk, Megan M; Van Raamsdonk, Jeremy M

    2016-12-01

    Huntington's disease (HD) is an adult onset neurodegenerative disorder for which there is currently no cure. While HD patients and animal models of the disease exhibit increased oxidative damage, it is currently uncertain to what extent oxidative stress contributes to disease pathogenesis. In this work, we use a genetic approach to define the role of oxidative stress in HD. We find that a C. elegans model of HD expressing a disease-length polyglutamine tract in the body wall muscle is hypersensitive to oxidative stress and shows an upregulation of antioxidant defense genes, indicating that the HD worm model has increased levels of oxidative stress. To determine whether this increase in oxidative stress contributes to the development of polyglutamine-toxicity phenotypes in this HD model, we examined the effect of deleting individual superoxide dismutase (sod) genes in the HD worm model. As predicted, we found that deletion of sod genes in the HD worm model resulted in a clear increase in sensitivity to oxidative stress. However, we found that increasing oxidative stress in the HD worm model did not exacerbate deficits caused by polyglutamine toxicity. We confirmed these observations in two worm models expressing disease-length polyglutamine tracts in neurons. Furthermore, we found that treatment with antioxidants failed to rescue movement deficits or decrease aggregation in HD worm models. Combined, this suggests that the increase in oxidative stress in worm models of HD does not contribute to the phenotypic deficits observed in these worms, and provides a possible explanation for the failure of antioxidants in HD clinical trials.

  1. Evaluation of Oxidative Stress in Bipolar Disorder in terms of Total Oxidant Status, Total Antioxidant Status, and Oxidative Stress Index

    PubMed Central

    CİNGİ YİRÜN, Merve; ÜNAL, Kübranur; ALTUNSOY ŞEN, Neslihan; YİRÜN, Onur; AYDEMİR, Çiğdem; GÖKA, Erol

    2016-01-01

    Introduction 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). Methods 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. Results 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. Conclusion 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. PMID:28373794

  2. Oxidative Stress and ADHD: A Meta-Analysis

    PubMed Central

    Joseph, Nidhin; Zhang-James, Yanli; Perl, Andras; Faraone, Stephen V.

    2017-01-01

    Objective To clarify the role of oxidative stress and antioxidant activity in ADHD. Method We examined the association of ADHD and oxidative stress by applying random effects meta-analysis to studies of oxidative stress and antioxidant status in medication naive patients with ADHD and controls. Results Six studies of a total of 231 ADHD patients and 207 controls met our selection criteria. The association between ADHD and antioxidant status was not significant. We found a significant association between ADHD and oxidative stress that could not be accounted for by publication bias. The significant association lost significance after correcting for intrastudy clustering. No one observation accounted for the positive result. Conclusion These results are preliminary given the small number of studies. They suggest that patients with ADHD have normal levels of antioxidant production, but that their response to oxidative stress is insufficient, leading to oxidative damage. PMID:24232168

  3. Indium and indium tin oxide induce endoplasmic reticulum stress and oxidative stress in zebrafish (Danio rerio).

    PubMed

    Brun, Nadja Rebecca; Christen, Verena; Furrer, Gerhard; Fent, Karl

    2014-10-07

    Indium and indium tin oxide (ITO) are extensively used in electronic technologies. They may be introduced into the environment during production, use, and leaching from electronic devices at the end of their life. At present, surprisingly little is known about potential ecotoxicological implications of indium contamination. Here, molecular effects of indium nitrate (In(NO3)3) and ITO nanoparticles were investigated in vitro in zebrafish liver cells (ZFL) cells and in zebrafish embryos and novel insights into their molecular effects are provided. In(NO3)3 led to induction of endoplasmic reticulum (ER) stress response, induction of reactive oxygen species (ROS) and induction of transcripts of pro-apoptotic genes and TNF-α in vitro at a concentration of 247 μg/L. In(NO3)3 induced the ER stress key gene BiP at mRNA and protein level, as well as atf6, which ultimately led to induction of the important pro-apoptotic marker gene chop. The activity of In(NO3)3 on ER stress induction was much stronger than that of ITO, which is explained by differences in soluble free indium ion concentrations. The effect was also stronger in ZFL cells than in zebrafish embryos. Our study provides first evidence of ER stress and oxidative stress induction by In(NO3)3 and ITO indicating a critical toxicological profile that needs further investigation.

  4. Biphasic regulation of lysosomal exocytosis by oxidative stress.

    PubMed

    Ravi, Sreeram; Peña, Karina A; Chu, Charleen T; Kiselyov, Kirill

    2016-11-01

    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.

  5. Oxidative stress, free radicals and protein peroxides.

    PubMed

    Gebicki, Janusz M

    2016-04-01

    Primary free radicals generated under oxidative stress in cells and tissues produce a cascade of reactive secondary radicals, which attack biomolecules with efficiency determined by the reaction rate constants and target concentration. Proteins are prominent targets because they constitute the bulk of the organic content of cells and tissues and react readily with many of the secondary radicals. The reactions commonly lead to the formation of carbon-centered radicals, which generally convert in vivo to peroxyl radicals and finally to semistable hydroperoxides. All of these intermediates can initiate biological damage. This article outlines the advantages of the application of ionizing radiations to studies of radicals, with particular reference to the generation of desired radicals, studies of the kinetics of their reactions and correlating the results with events in biological systems. In one such application, formation of protein hydroperoxides in irradiated cells was inhibited by the intracellular ascorbate and glutathione.

  6. The Oxygen Paradox, oxidative stress, and ageing.

    PubMed

    Davies, Kelvin J A

    2016-04-01

    Professor Helmut Sies is being lauded in this special issue of Archives of Biochemistry & Biophysics, on the occasion of his retirement as Editor-in-Chief. There is no doubt that Helmut has exerted an enormously positive influence on this journal, the fields of Biochemistry & Biophysics in general, and the areas of free radical and redox biology & medicine in particular. Helmut Sies' many discoveries about peroxide metabolism, glutathione, glutathione peroxidases, singlet oxygen, carotenoids in general and lycopene in particular, and flavonoids, fill the pages of his more than 600 publications. In addition, he will forever be remembered for coining the term 'oxidative stress' that is so widely used (and sometimes abused) by most of his colleagues.

  7. Thyroid Hormones, Oxidative Stress, and Inflammation.

    PubMed

    Mancini, Antonio; Di Segni, Chantal; Raimondo, Sebastiano; Olivieri, Giulio; Silvestrini, Andrea; Meucci, Elisabetta; Currò, Diego

    2016-01-01

    Inflammation and oxidative stress (OS) are closely related processes, as well exemplified in obesity and cardiovascular diseases. OS is also related to hormonal derangement in a reciprocal way. Among the various hormonal influences that operate on the antioxidant balance, thyroid hormones play particularly important roles, since both hyperthyroidism and hypothyroidism have been shown to be associated with OS in animals and humans. In this context, the nonthyroidal illness syndrome (NTIS) that typically manifests as reduced conversion of thyroxine (T4) to triiodothyronine (T3) in different acute and chronic systemic conditions is still a debated topic. The pathophysiological mechanisms of this syndrome are reviewed, together with the roles of deiodinases, the enzymes responsible for the conversion of T4 to T3, in both physiological and pathological situations. The presence of OS indexes in NTIS supports the hypothesis that it represents a condition of hypothyroidism at the tissue level and not only an adaptive mechanism to diseases.

  8. Cerulein Pancreatitis: Oxidative Stress, Inflammation, and Apoptosis

    PubMed Central

    2008-01-01

    Cerulein pancreatitis is similar to human edematous pancreatitis, manifesting with dysregulation of digestive enzyme production and cytoplasmic vacuolization, the death of acinar cells, edema formation, and infiltration of inflammatory cells into the pancreas. Reactive oxygen species are involved in nuclear factor-κB activation, cytokine expression, apoptosis and pathogenesis of pancreatitis. There is recent evidence that cerulein activates NADPH oxidase, which is a major source of reactive oxygen species during inflammation and apoptosis in pancreatic acinar cells. In addition, the Janus kinase/signal transducer and activator of transcription pathway has been suggested as being involved in inflammatory signaling in the pancreas. This review discusses the involvement of oxidative stress in inflammation and apoptosis in pancreatic acinar cells stimulated with cerulein as an in vitro model of pancreatitis. PMID:20485614

  9. Thyroid Hormones, Oxidative Stress, and Inflammation

    PubMed Central

    Raimondo, Sebastiano; Olivieri, Giulio; Meucci, Elisabetta; Currò, Diego

    2016-01-01

    Inflammation and oxidative stress (OS) are closely related processes, as well exemplified in obesity and cardiovascular diseases. OS is also related to hormonal derangement in a reciprocal way. Among the various hormonal influences that operate on the antioxidant balance, thyroid hormones play particularly important roles, since both hyperthyroidism and hypothyroidism have been shown to be associated with OS in animals and humans. In this context, the nonthyroidal illness syndrome (NTIS) that typically manifests as reduced conversion of thyroxine (T4) to triiodothyronine (T3) in different acute and chronic systemic conditions is still a debated topic. The pathophysiological mechanisms of this syndrome are reviewed, together with the roles of deiodinases, the enzymes responsible for the conversion of T4 to T3, in both physiological and pathological situations. The presence of OS indexes in NTIS supports the hypothesis that it represents a condition of hypothyroidism at the tissue level and not only an adaptive mechanism to diseases. PMID:27051079

  10. Air pollution, oxidative stress, and Alzheimer's disease.

    PubMed

    Moulton, Paula Valencia; Yang, Wei

    2012-01-01

    Alzheimer's disease (AD) is the most common form of dementia affecting millions of people worldwide and will continue to affect millions more with population aging on the rise. AD causality is multifactorial. Known causal factors include genetic predisposition, age, and sex. Environmental toxins such as air pollution (AP) have also been implicated in AD causation. Exposure to AP can lead to chronic oxidative stress (OS), which is involved in the pathogenesis of AD. Whereas AP plays a role in AD pathology, the epidemiological evidence for this association is limited. Given the significant prevalence of AP exposure combined with increased population aging, epidemiological evidence for this link is important to consider. In this paper, we examine the existing evidence supporting the relationship between AP, OS, and AD and provide recommendations for future research on the population level, which will provide evidence in support of public health interventions.

  11. Effect of hyperbaric oxygen on cyclosporine-induced nephrotoxicity and oxidative stress in rats.

    PubMed

    Ay, Hakan; Uzun, Gunalp; Onem, Yalcin; Aydinoz, Secil; Yildiz, Senol; Bilgi, Oguz; Topal, Turgut; Atasoyu, Enes Murat

    2007-01-01

    Reactive oxygen species have been suggested to be involved in cyclosporine nephrotoxicity. Hyperbaric oxygen is known to induce the generation of reactive oxygen species in tissues. The aim of this study was to investigate whether the use of hyperbaric oxygen concurrently with cyclosporine potentiates cyclosporine nephrotoxicity by inducing oxidative stress in kidneys. The study consisted of four groups of rats: a control group, a cyclosporine group (15 mg/kg/day intraperitoneally for 14 days), a hyperbaric oxygen group (60 min. every day for five days at 2.5 atmosphere absolute), and a cyclosporine + hyperbaric oxygen group (cyclosporine 15 mg/kg/day intraperitoneally for 14 days + hyperbaric oxygen for 60 min at 2.5 atmosphere absolute every day for five days on the last five days of cyclosporine treatment). Oxidative stress was determined by measuring renal thiobarbituric acid-reactive substances content, renal superoxide dismutase, and glutathione peroxidase activities. Cyclosporine increased serum urea and creatinine levels, indicating the development of nephrotoxicity, and induced significant oxidative stress in rat kidneys. Hyperbaric oxygen alone did not alter any of the biochemical and oxidative stress parameters compared to the control group. When used concurrently with cyclosporine, hyperbaric oxygen significantly reduced cyclosporine-induced oxidative stress, but it neither attenuated nor aggravated cyclosporine-induced nephrotoxicity. These results suggest that reactive oxygen species are involved in cyclosporine nephrotoxicity, but are not the direct cause of the toxicity. Although concurrent use of cyclosporine and hyperbaric oxygen did not exacerbate cyclosporine nephrotoxicity in this model, we recommend that the renal functions of patients be monitored periodically when these treatments are used concurrently.

  12. Metabolomics of Oxidative Stress in Recent Studies of Endogenous and Exogenously Administered Intermediate Metabolites

    PubMed Central

    Liu, Jia; Litt, Lawrence; Segal, Mark R.; Kelly, Mark J. S.; Pelton, Jeffrey G.; Kim, Myungwon

    2011-01-01

    Aerobic metabolism occurs in a background of oxygen radicals and reactive oxygen species (ROS) that originate from the incomplete reduction of molecular oxygen in electron transfer reactions. The essential role of aerobic metabolism, the generation and consumption of ATP and other high energy phosphates, sustains a balance of approximately 3000 essential human metabolites that serve not only as nutrients, but also as antioxidants, neurotransmitters, osmolytes, and participants in ligand-based and other cellular signaling. In hypoxia, ischemia, and oxidative stress, where pathological circumstances cause oxygen radicals to form at a rate greater than is possible for their consumption, changes in the composition of metabolite ensembles, or metabolomes, can be associated with physiological changes. Metabolomics and metabonomics are a scientific disciplines that focuse on quantifying dynamic metabolome responses, using multivariate analytical approaches derived from methods within genomics, a discipline that consolidated innovative analysis techniques for situations where the number of biomarkers (metabolites in our case) greatly exceeds the number of subjects. This review focuses on the behavior of cytosolic, mitochondrial, and redox metabolites in ameliorating or exacerbating oxidative stress. After reviewing work regarding a small number of metabolites—pyruvate, ethyl pyruvate, and fructose-1,6-bisphosphate—whose exogenous administration was found to ameliorate oxidative stress, a subsequent section reviews basic multivariate statistical methods common in metabolomics research, and their application in human and preclinical studies emphasizing oxidative stress. Particular attention is paid to new NMR spectroscopy methods in metabolomics and metabonomics. Because complex relationships connect oxidative stress to so many physiological processes, studies from different disciplines were reviewed. All, however, shared the common goal of ultimately developing

  13. Metabolomics of oxidative stress in recent studies of endogenous and exogenously administered intermediate metabolites.

    PubMed

    Liu, Jia; Litt, Lawrence; Segal, Mark R; Kelly, Mark J S; Pelton, Jeffrey G; Kim, Myungwon

    2011-01-01

    Aerobic metabolism occurs in a background of oxygen radicals and reactive oxygen species (ROS) that originate from the incomplete reduction of molecular oxygen in electron transfer reactions. The essential role of aerobic metabolism, the generation and consumption of ATP and other high energy phosphates, sustains a balance of approximately 3000 essential human metabolites that serve not only as nutrients, but also as antioxidants, neurotransmitters, osmolytes, and participants in ligand-based and other cellular signaling. In hypoxia, ischemia, and oxidative stress, where pathological circumstances cause oxygen radicals to form at a rate greater than is possible for their consumption, changes in the composition of metabolite ensembles, or metabolomes, can be associated with physiological changes. Metabolomics and metabonomics are a scientific disciplines that focuse on quantifying dynamic metabolome responses, using multivariate analytical approaches derived from methods within genomics, a discipline that consolidated innovative analysis techniques for situations where the number of biomarkers (metabolites in our case) greatly exceeds the number of subjects. This review focuses on the behavior of cytosolic, mitochondrial, and redox metabolites in ameliorating or exacerbating oxidative stress. After reviewing work regarding a small number of metabolites-pyruvate, ethyl pyruvate, and fructose-1,6-bisphosphate-whose exogenous administration was found to ameliorate oxidative stress, a subsequent section reviews basic multivariate statistical methods common in metabolomics research, and their application in human and preclinical studies emphasizing oxidative stress. Particular attention is paid to new NMR spectroscopy methods in metabolomics and metabonomics. Because complex relationships connect oxidative stress to so many physiological processes, studies from different disciplines were reviewed. All, however, shared the common goal of ultimately developing "omics

  14. The Role of Oxidative Stress and Antioxidants in Liver Diseases.

    PubMed

    Li, Sha; Tan, Hor-Yue; Wang, Ning; Zhang, Zhang-Jin; Lao, Lixing; Wong, Chi-Woon; Feng, Yibin

    2015-11-02

    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.

  15. Strategies for Reducing or Preventing the Generation of Oxidative Stress

    PubMed Central

    Poljsak, B.

    2011-01-01

    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

  16. The Role of Oxidative Stress and Antioxidants in Liver Diseases

    PubMed Central

    Li, Sha; Tan, Hor-Yue; Wang, Ning; Zhang, Zhang-Jin; Lao, Lixing; Wong, Chi-Woon; Feng, Yibin

    2015-01-01

    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

  17. Oxidative stress decreases with elevation in the lizard Psammodromus algirus.

    PubMed

    Reguera, Senda; Zamora-Camacho, Francisco J; Trenzado, Cristina E; Sanz, Ana; Moreno-Rueda, Gregorio

    2014-06-01

    Oxidative stress is considered one of the main ecological and evolutionary forces. Several environmental stressors vary geographically and thus organisms inhabiting different sites face different oxidant environments. Nevertheless, there is scarce information about how oxidative damage and antioxidant defences vary geographically in animals. Here we study how oxidative stress varies from lowlands (300-700 m asl) to highlands (2200-2500 m asl) in the lizard Psammodromus algirus. To accomplish this, antioxidant enzymatic activity (catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione transferase, DT-diaphorase) and lipid peroxidation were assayed in tissue samples from the lizards' tail. Lipid peroxidation was higher in individuals from lowlands than from highlands, indicating higher oxidative stress in lowland lizards. These results suggest that environmental conditions are less oxidant at high elevations with respect to low ones. Therefore, our study shows that oxidative stress varies geographically, which should have important consequences for our understanding of geographic variation in physiology and life-history of organisms.

  18. [Selenium and oxidative stress in cancer patients].

    PubMed

    Gorozhanskaia, É G; Sviridova, S P; Dobrovol'skaia, M M; Zybrikhina, G N; Kashnia, Sh R

    2013-01-01

    In order to identify the features of violations of free-radical processes in blood serum of 94 untreated cancer patients with different localization of the tumor (cancer of the stomach, colon, breast, ovarian, hemoblastoses) were determined selenium levels and indicators of oxidative stress (sum of metabolites of nitrogen--NOx, the level of superoxide dismutase--Cu/ZnSOD and malondiialdehyde-MDA, and the activity of catalase). In addition, 40 patients with malignant liver disease and clinical signs of liver failure in the early postoperative period was carried out a comparative evaluation of the efficacy of selenium-containing drug "Selenaze" (sodium selenite pentahydrate). It was found that selenium levels in cancer patients by 25-30% below the norm of 110-120 mg/l at a rate of 73.0 +/- 2.6 mg/l. Low levels of NOx was detected in patients with all tumor localizations (22.1 +/- 1.1 microM, with normal range 28.4 +/- 0.9 microM). The exceptions were patients with extensive malignant process in the liver, in which the NOx levels were significantly higher than normal (p < 0.001). The high level of NOx has a toxic effect on the hepatocyte, causing metabolic disorders and inflammatory-necrotic changes in the liver. Elevated levels of SOD and MDA in normal values of catalase activity was detected in all patients. The use of "Selenaze" in postoperative patients with tumors of the liver increased selenium levels by 10-12%, which was accompanied by a decrease in the content of SOD and NOx, and contributed to earlier recovery of detoxic and synthetic liver function. These findings point to an intensification of oxidative stress and metabolic disorders in the malignant process, which is the basis for metabolic correction.

  19. Traumatic stress, oxidative stress and posttraumatic stress disorder: neurodegeneration and the accelerated-aging hypothesis

    PubMed Central

    Miller, Mark W.; Sadeh, Naomi

    2014-01-01

    Posttraumatic stress disorder (PTSD) is associated with elevated risk for a variety of age-related diseases and neurodegeneration. In this paper, we review evidence relevant to the hypothesis that chronic PTSD constitutes a form of persistent life stress that potentiates oxidative stress (OXS) and accelerates cellular aging. We provide an overview of empirical studies that have examined the effects of psychological stress on OXS, discuss the stress-perpetuating characteristics of PTSD, and then identify mechanisms by which PTSD might promote OXS and accelerated aging. We review studies on OXS-related genes and the role that they may play in moderating the effects of PTSD on neural integrity and conclude with a discussion of directions for future research on antioxidant treatments and biomarkers of accelerated aging in PTSD. PMID:25245500

  20. Oxidative and Nitrative Stress in Neurodegeneration

    PubMed Central

    Cobb, Catherine A.; Cole, Marsha P.

    2015-01-01

    Aerobes require oxygen for metabolism and normal free radical formation. As a result, maintaining the redox homeostasis is essential for brain cell survival due to their high metabolic energy requirement to sustain electrochemical gradients, neurotransmitter release, and membrane lipid stability. Further, brain antioxidant levels are limited compared to other organs and less able to compensate for reactive oxygen and nitrogen species (ROS/RNS) generation which contribute oxidative/nitrative stress (OS/NS). Antioxidant treatments such as vitamin E, minocycline, and resveratrol mediate neuroprotection by prolonging the incidence of or reversing OS and NS conditions. Redox imbalance occurs when the antioxidant capacity is overwhelmed, consequently leading to activation of alternate pathways that remain quiescent under normal conditions. If OS/NS fails to lead to adaptation, tissue damage and injury ensue, resulting in cell death and/or disease. The progression of OS/NS-mediated neurodegeneration along with contributions from microglial activation, dopamine metabolism, and diabetes comprise a detailed interconnected pathway. This review proposes a significant role for OS/NS and more specifically, lipid peroxidation (LPO) and other lipid modifications, by triggering microglial activation to elicit a neuroinflammatory state potentiated by diabetes or abnormal dopamine metabolism. Subsequently, sustained stress in the neuroinflammatory state overwhelms cellular defenses and prompts neurotoxicity resulting in the onset or amplification of brain damage. PMID:26024962

  1. Oxidative stress causes plasma protein modification.

    PubMed

    Tetik, Sermin; Kiliç, Arzu; Aksoy, Halil; Rizaner, Nahit; Ahmad, Sarfraz; Yardimci, Turay

    2015-01-01

    We investigated the effect of oxidative systems on plasma proteins using Chloramine-T, a source of free radicals. Plasma specimens from 10 healthy volunteers were treated with 40 mmol/L Chloramine-T (1:1 v/v). Total protein and plasma carbonyl levels were evaluated spectrophotometrically. Identification of plasma proteins modifications was performed by SDS-PAGE, protein and lipid electrophoresis. Protein fragmentation was evaluated by HPLC. Total protein levels of oxidised plasmas were significantly lower (4.08 ± 0.12 g/dL) than control (7.86 ± 0.03 g/dL) (P < 0.01). Plasma carbonyl levels were higher (1.94 ± 0.38 nmol/mg protein) in oxidised plasma than that of control (0.03 ± 0.01 nmol/mg protein) (P < 0.01). Plasma oxidation had no significant effect on the levels of proteins and lipids. Protein fragmentations were detected in oxidised groups compared to those of the control. We conclude that protein modifications have direct effect on the protein functions, which are related to stress agent, its treatment period(s), and the methodology used for evaluating such experimental results.

  2. Influence of Oxidative Stress on Stored Platelets

    PubMed Central

    2016-01-01

    Platelet storage and its availability for transfusion are limited to 5-6 days. Oxidative stress (OS) is one of the causes for reduced efficacy and shelf-life of platelets. The studies on platelet storage have focused on improving the storage conditions by altering platelet storage solutions, temperature, and materials. Nevertheless, the role of OS on platelet survival during storage is still unclear. Hence, this study was conducted to investigate the influence of storage on platelets. Platelets were stored for 12 days at 22°C. OS markers such as aggregation, superoxides, reactive oxygen species, glucose, pH, lipid peroxidation, protein oxidation, and antioxidant enzymes were assessed. OS increased during storage as indicated by increments in aggregation, superoxides, pH, conjugate dienes, and superoxide dismutase and decrements in glucose and catalase. Thus, platelets could endure OS till 6 days during storage, due to the antioxidant defense system. An evident increase in OS was observed from day 8 of storage, which can diminish the platelet efficacy. The present study provides an insight into the gradual changes occurring during platelet storage. This lays the foundation towards new possibilities of employing various antioxidants as additives in storage solutions. PMID:26949396

  3. Oxidative stress, protein modification and Alzheimer disease.

    PubMed

    Tramutola, A; Lanzillotta, C; Perluigi, M; Butterfield, D Allan

    2016-06-15

    Alzheimer disease (AD) is a progressive neurodegenerative disease that affects the elderly population with complex etiology. Many hypotheses have been proposed to explain different causes of AD, but the exact mechanisms remain unclear. In this review, we focus attention on the oxidative-stress hypothesis of neurodegeneration and we discuss redox proteomics approaches to analyze post-mortem human brain from AD brain. Collectively, these studies have provided valuable insights into the molecular mechanisms involved both in the pathogenesis and progression of AD, demonstrating the impairment of numerous cellular processes such as energy production, cellular structure, signal transduction, synaptic function, mitochondrial function, cell cycle progression, and degradative systems. Each of these cellular functions normally contributes to maintain healthy neuronal homeostasis, so the deregulation of one or more of these functions could contribute to the pathology and clinical presentation of AD. In particular, we discuss the evidence demonstrating the oxidation/dysfunction of a number of enzymes specifically involved in energy metabolism that support the view that reduced glucose metabolism and loss of ATP are crucial events triggering neurodegeneration and progression of AD.

  4. Correlation of Zinc with Oxidative Stress Biomarkers

    PubMed Central

    Morales-Suárez-Varela, María; Llopis-González, Agustín; González-Albert, Verónica; López-Izquierdo, Raúl; González-Manzano, Isabel; Cháves, Javier; Huerta-Biosca, Vicente; Martin-Escudero, Juan C.

    2015-01-01

    Hypertension and smoking are related with oxidative stress (OS), which in turn reports on cellular aging. Zinc is an essential element involved in an individual’s physiology. The aim of this study was to evaluate the relation of zinc levels in serum and urine with OS and cellular aging and its effect on the development of hypertension. In a Spanish sample with 1500 individuals, subjects aged 20–59 years were selected, whose zinc intake levels fell within the recommended limits. These individuals were classified according to their smoking habits and hypertensive condition. A positive correlation was found (Pearson’s C = 0.639; p = 0.01) between Zn serum/urine quotient and oxidized glutathione levels (GSSG). Finally, risk of hypertension significantly increased when the GSSG levels exceeded the 75 percentile; OR = 2.80 (95%CI = 1.09–7.18) and AOR = 3.06 (95%CI = 0.96–9.71). Low zinc levels in serum were related with OS and cellular aging and were, in turn, to be a risk factor for hypertension.  PMID:25774936

  5. Oxidative stress in atherosclerosis and diabetes.

    PubMed

    Lankin, V Z; Lisina, M O; Arzamastseva, N E; Konovalova, G G; Nedosugova, L V; Kaminnyi, A I; Tikhaze, A K; Ageev, F T; Kukharchuk, V V; Belenkov, Yu N

    2005-07-01

    We measured the content of lipid peroxides in plasma LDL from patients with chronic CHD not accompanied by hypercholesterolemia; CHD and hypercholesterolemia; type 2 diabetes mellitus and decompensation of carbohydrate metabolism; and CHD, circulatory insufficiency, and type 2 diabetes mellitus (without hypercholesterolemia). The content of lipid peroxides in LDL isolated from blood plasma by differential ultracentrifugation in a density gradient was estimated by a highly specific method with modifications (reagent Fe(2+) xylene orange and triphenylphosphine as a reducing agent for organic peroxides). The content of lipid peroxides in LDL from patients was much higher than in controls (patients without coronary heart disease and diabetes). Hypercholesterolemia and diabetes can be considered as factors promoting LDL oxidation in vivo. Our results suggest that stimulation of lipid peroxidation in low-density lipoproteins during hypercholesterolemia and diabetes is associated with strong autooxidation of cholesterol and glucose during oxidative and carbonyl (aldehyde) stress, respectively. These data illustrate a possible mechanism of the progression of atherosclerosis in patients with diabetes mellitus.

  6. Effect of lysozyme chloride on betel quid chewing aggravated gastric oxidative stress and hemorrhagic ulcer in diabetic rats

    PubMed Central

    Hung, Chen-Road

    2005-01-01

    AIM: To evaluate the protective effect of lysozyme chloride on betel quid chewing (BQC) aggravated gastric oxidative stress and hemorrhagic ulcer in rats with diabetes mellitus (DM). METHODS: Male Wistar rats were challenged intravenously with streptozotocin (65 mg/kg) to induce DM. Rats were fed with regular pellet food or BQC-containing diets. After 90 d, rats were deprived of food for 24 h. Rat stomachs were irrigated for 3 h with normal saline or simulated gastric juice. Rats were killed and gastric specimens were harvested. RESULTS: An enhancement of various gastric ulcerogenic parameters, including acid back-diffusion, mucosal lipid peroxide generation, as well as decreased glutathione levels and mucus content, were observed in DM rats. After feeding DM rats with BQC, an exacerbation of these ulcero-genic parameters was achieved. Gastric juice caused a further aggravation of these ulcerogenic parameters. Daily intragastric lysozyme chloride dose-dependently inhibited exacerbation of various ulcerogenic parameters in those BQC-fed DM rats. CONCLUSION: (1) Gastric juice could aggravate both DM and BQC-fed DM rat hemorrhagic ulcer; (2) BQC exacerbated gastric hemorrhagic ulcer in DM rats via enhancing oxidative stress and reducing defensive factors; (3) lysozyme chloride effectively protected BQC aggravated gastric damage in DM rats. PMID:16270397

  7. Oxidative stress in zebrafish (Danio rerio) sperm.

    PubMed

    Hagedorn, Mary; McCarthy, Megan; Carter, Virginia L; Meyers, Stuart A

    2012-01-01

    Laboratories around the world have produced tens of thousands of mutant and transgenic zebrafish lines. As with mice, maintaining all of these valuable zebrafish genotypes is expensive, risky, and beyond the capacity of even the largest stock centers. Because reducing oxidative stress has become an important aspect of reducing the variability in mouse sperm cryopreservation, we examined whether antioxidants might improve cryopreservation of zebrafish sperm. Four experiments were conducted in this study. First, we used the xanthine-xanthine oxidase (X-XO) system to generate reactive oxygen species (ROS). The X-XO system was capable of producing a stress reaction in zebrafish sperm reducing its sperm motility in a concentration dependent manner (P<0.05). Second, we examined X-XO and the impact of antioxidants on sperm viability, ROS and motility. Catalase (CAT) mitigated stress and maintained viability and sperm motility (P>0.05), whereas superoxide dismutase (SOD) and vitamin E did not (P<0.05). Third, we evaluated ROS in zebrafish spermatozoa during cryopreservation and its effect on viability and motility. Methanol (8%) reduced viability and sperm motility (P<0.05), but the addition of CAT mitigated these effects (P>0.05), producing a mean 2.0 to 2.9-fold increase in post-thaw motility. Fourth, we examined the effect of additional cryoprotectants and CAT on fresh sperm motility. Cryoprotectants, 8% methanol and 10% dimethylacetamide (DMA), reduced the motility over the control value (P<0.5), whereas 10% dimethylformamide (DMF) with or without CAT did not (P>0.05). Zebrafish sperm protocols should be modified to improve the reliability of the cryopreservation process, perhaps using a different cryoprotectant. Regardless, the simple addition of CAT to present-day procedures will significantly improve this process, assuring increased and less variable fertilization success and allowing resource managers to dependably plan how many straws are needed to safely

  8. Effect of heat stress on oxidative stress, lipid peroxidation and some stress parameters in broilers.

    PubMed

    Altan, O; Pabuçcuoğlu, A; Altan, A; Konyalioğlu, S; Bayraktar, H

    2003-09-01

    1. This study was conducted to determine the effects of heat stress on fearfulness, leucocyte components, oxidative stress and lipid peroxidation in two commercial broiler strains, Cobb (C) and Ross (R). 2. At 36 and 37 d of age birds were exposed to 38 +/- 1 degree C for 3 h. Rectal temperatures, duration of tonic immobility (TI), haematocrit values, proportions of leucocyte components (heterophil, lymphocyte, basophil, eosinophil, monocyte), malondialdehyde (MDA) concentrations and antioxidant enzyme activities (CAT, SOD, GPx) of all the birds were determined, before and after heat treatment. 3. Rectal temperatures increased and haematocrit values decreased in birds exposed to heat stress. Heat stress caused a significant increase in heterophil/lymphocyte and in basophil ratios. 4. Exposing birds to heat stress increased duration of TI, suggesting heat-stressed birds tended to be more fearful. 5. Heat stress resulted in a significant Genotype x Treatment interaction for MDA concentration. CAT, SOD and GPx activities; MDA concentrations in heat-stressed R strain birds were greater than in heat-stressed C strain birds.

  9. Potential roles of environmental oxidative stress in aflatoxin production revealed in the Aspergillus flavus transcriptome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aflatoxin contamination caused by Aspergillus flavus infection in crops is known to be exacerbated primarily by abiotic stresses such as drought stress, and biotic stresses such as arthropod infestation. These stresses result in the production and accumulation of reactive oxygen species (ROS) in the...

  10. Classification of oxidative stress based on its intensity

    PubMed Central

    Lushchak, Volodymyr I.

    2014-01-01

    In living organisms production of reactive oxygen species (ROS) is counterbalanced by their elimination and/or prevention of formation which in concert can typically maintain a steady-state (stationary) ROS level. However, this balance may be disturbed and lead to elevated ROS levels called oxidative stress. To our best knowledge, there is no broadly acceptable system of classification of oxidative stress based on its intensity due to which proposed here system may be helpful for interpretation of experimental data. Oxidative stress field is the hot topic in biology and, to date, many details related to ROS-induced damage to cellular components, ROS-based signaling, cellular responses and adaptation have been disclosed. However, it is common situation when researchers experience substantial difficulties in the correct interpretation of oxidative stress development especially when there is a need to characterize its intensity. Careful selection of specific biomarkers (ROS-modified targets) and some system may be helpful here. A classification of oxidative stress based on its intensity is proposed here. According to this classification there are four zones of function in the relationship between “Dose/concentration of inducer” and the measured “Endpoint”: I – basal oxidative stress (BOS); II – low intensity oxidative stress (LOS); III – intermediate intensity oxidative stress (IOS); IV – high intensity oxidative stress (HOS). The proposed classification will be helpful to describe experimental data where oxidative stress is induced and systematize it based on its intensity, but further studies will be in need to clear discriminate between stress of different intensity. PMID:26417312

  11. Blood and Oxidative Stress (BOS): Soyuz mission "Eneide"

    NASA Astrophysics Data System (ADS)

    Rizzo, Angela Maria; Adorni, Laura; Montorfano, Gigliola; Negroni, Manuela; Zava, Stefania; Berra, Bruno

    2007-09-01

    The aim of this experiment was to assay astronaut antioxidant status, to analyse red blood cell membrane composition of astronauts prior and after flight and to study the correlation with oxidative stress that erythrocytes have undergone due to space radiations. Results obtained from this single case study, indicate that during a short time flight, erythrocytes decrease their antioxidant defences, to counteract oxidative stress.

  12. Curcumin alleviates oxidative stress and mitochondrial dysfunction in astrocytes.

    PubMed

    Daverey, Amita; Agrawal, Sandeep K

    2016-10-01

    Oxidative stress plays a critical role in various neurodegenerative diseases, thus alleviating oxidative stress is a potential strategy for therapeutic intervention and/or prevention of neurodegenerative diseases. In the present study, alleviation of oxidative stress through curcumin is investigated in A172 (human glioblastoma cell line) and HA-sp (human astrocytes cell line derived from the spinal cord) astrocytes. H2O2 was used to induce oxidative stress in astrocytes (A172 and HA-sp). Data show that H2O2 induces activation of astrocytes in dose- and time-dependent manner as evident by increased expression of GFAP in A172 and HA-sp cells after 24 and 12h respectively. An upregulation of Prdx6 was also observed in A172 and HA-sp cells after 24h of H2O2 treatment as compared to untreated control. Our data also showed that curcumin inhibits oxidative stress-induced cytoskeleton disarrangement, and impedes the activation of astrocytes by inhibiting upregulation of GFAP, vimentin and Prdx6. In addition, we observed an inhibition of oxidative stress-induced inflammation, apoptosis and mitochondria fragmentation after curcumin treatment. Therefore, our results suggest that curcumin not only protects astrocytes from H2O2-induced oxidative stress but also reverses the mitochondrial damage and dysfunction induced by oxidative stress. This study also provides evidence for protective role of curcumin on astrocytes by showing its effects on attenuating reactive astrogliosis and inhibiting apoptosis.

  13. Altered Gravity Induces Oxidative Stress in Drosophila Melanogaster

    NASA Technical Reports Server (NTRS)

    Bhattacharya, Sharmila; Hosamani, Ravikumar

    2015-01-01

    Altered gravity environments can induce increased oxidative stress in biological systems. Microarray data from our previous spaceflight experiment (FIT experiment on STS-121) indicated significant changes in the expression of oxidative stress genes in adult fruit flies after spaceflight. Currently, our lab is focused on elucidating the role of hypergravity-induced oxidative stress and its impact on the nervous system in Drosophila melanogaster. Biochemical, molecular, and genetic approaches were combined to study this effect on the ground. Adult flies (2-3 days old) exposed to acute hypergravity (3g, for 1 hour and 2 hours) showed significantly elevated levels of Reactive Oxygen Species (ROS) in fly brains compared to control samples. This data was supported by significant changes in mRNA expression of specific oxidative stress and antioxidant defense related genes. As anticipated, a stress-resistant mutant line, Indy302, was less vulnerable to hypergravity-induced oxidative stress compared to wild-type flies. Survival curves were generated to study the combined effect of hypergravity and pro-oxidant treatment. Interestingly, many of the oxidative stress changes that were measured in flies showed sex specific differences. Collectively, our data demonstrate that altered gravity significantly induces oxidative stress in Drosophila, and that one of the organs where this effect is evident is the brain.

  14. Antioxidant status and biomarkers of oxidative stress in canine lymphoma

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background – Oxidative stress might play a role in carcinogenesis, as well as impacting morbidity and mortality of veterinary cancer patients. The purpose of this study was to evaluate antioxidant concentrations and biomarkers of oxidative stress in dogs with newly-diagnosed lymphoma prior to treatm...

  15. Protein Sulfenylation: A Novel Readout of Environmental Oxidant Stress

    EPA Science Inventory

    Oxidative stress is a commonly cited mechanism of toxicity of environmental agents. Ubiquitous environmental chemicals such as the diesel exhaust component 1,2-naphthoquinone (1,2-NQ)induce oxidative stress by redox cycling, which generates hydrogen peroxide (H202). Cysteinylthio...

  16. Inhibiting corticosterone synthesis during fear memory formation exacerbates cued fear extinction memory deficits within the single prolonged stress model.

    PubMed

    Keller, Samantha M; Schreiber, William B; Stanfield, Briana R; Knox, Dayan

    2015-01-01

    Using the single prolonged stress (SPS) animal model of post-traumatic stress disorder (PTSD), previous studies suggest that enhanced glucocorticoid receptor (GR) expression leads to cued fear extinction retention deficits. However, it is unknown how the endogenous ligand of GRs, corticosterone (CORT), may contribute to extinction retention deficits in the SPS model. Given that CORT synthesis during fear learning is critical for fear memory consolidation and SPS enhances GR expression, CORT synthesis during fear memory formation could strengthen fear memory in SPS rats by enhancing GR activation during fear learning. In turn, this could lead to cued fear extinction retention deficits. We tested the hypothesis that CORT synthesis during fear learning leads to cued fear extinction retention deficits in SPS rats by administering the CORT synthesis inhibitor metyrapone to SPS and control rats prior to fear conditioning, and observed the effect this had on extinction memory. Inhibiting CORT synthesis during fear memory formation in control rats tended to decrease cued freezing, though this effect never reached statistical significance. Contrary to our hypothesis, inhibiting CORT synthesis during fear memory formation disrupted extinction retention in SPS rats. This finding suggests that even though SPS exposure leads to cued fear extinction memory deficits, CORT synthesis during fear memory formation enhances extinction retention in SPS rats. This suggests that stress-induced CORT synthesis in previously stressed rats can be beneficial.

  17. Oxidative Stress in Maternal Blood and Placenta From Mild Diabetic Rats

    PubMed Central

    Spada, Ana Paula Machado; Sinzato, Yuri Karen; Campos, Kleber Eduardo; Faria, Priscila Afonso; Dallaqua, Bruna; Calderon, Iracema Mattos Paranhos; Rudge, Marilza Vieira Cunha; Rodrigues, Tiago

    2014-01-01

    The aim of the present study was at evaluating the effects of oxidative stress in blood and placenta of mild diabetic Wistar rats. At birth, Wistar rats received citrate buffer (nondiabetic group, n = 15) and another group received streptozotocin (100 mg/kg, subcutaneous) to induce mild diabetes (diabetic, n = 15). The glycemia of these pregnant adult female rats were evaluated at days 0, 7, 14, and 21 of pregnancy, and at term pregnancy, the blood and placental samples were collected for oxidative stress measurements. The mild diabetes caused glycemia superior to 120 mg/dL during pregnancy, increased superoxide dismutase, glutathione peroxidase, glutathione reductase activities, and malondialdehyde levels in the blood, and catalase activity in the placenta. Thus, mild diabetes increased activities of antioxidant substances aiming at defending against the exacerbated oxidative stress but were not enough. The placenta also answered to diabetic milieu and increased antioxidant defense, showing that even a mild hyperglycemia was enough to cause placental and maternal blood changes. PMID:24458484

  18. Role of Differential Signaling Pathways and Oxidative Stress in Diabetic Cardiomyopathy

    PubMed Central

    Watanabe, Kenichi; Thandavarayan, Rajarajan A; Harima, Meilei; Sari, Flori R; Gurusamy, Narasimman; Veeraveedu, Punniyakoti T; Mito, Sayaka; Arozal, Wawaimuli; Sukumaran, Vijayakumar; Laksmanan, Arun Prasath; Soetikno, Vivian; Kodama, Makoto; Aizawa, Yoshifusa

    2010-01-01

    Diabetes mellitus increases the risk of heart failure independently of underlying coronary artery disease, and many believe that diabetes leads to cardiomyopathy. The underlying pathogenesis is partially understood. Several factors may contribute to the development of cardiac dysfunction in the absence of coronary artery disease in diabetes mellitus. There is growing evidence that excess generation of highly reactive free radicals, largely due to hyperglycemia, causes oxidative stress, which further exacerbates the development and progression of diabetes and its complications. Hyperglycemia-induced oxidative stress is a major risk factor for the development of micro-vascular pathogenesis in the diabetic myocardium, which results in myocardial cell death, hypertrophy, fibrosis, abnormalities of calcium homeostasis and endothelial dysfunction. Diabetes-mediated biochemical changes show cross-interaction and complex interplay culminating in the activation of several intracellular signaling molecules. Diabetic cardiomyopathy is characterized by morphologic and structural changes in the myocardium and coronary vasculature mediated by the activation of various signaling pathways. This review focuses on the oxidative stress and signaling pathways in the pathogenesis of the cardiovascular complications of diabetes, which underlie the development and progression of diabetic cardiomyopathy. PMID:22043204

  19. Oxidative stress in diabetes: implications for vascular and other complications.

    PubMed

    Pitocco, Dario; Tesauro, Manfredi; Alessandro, Rizzi; Ghirlanda, Giovanni; Cardillo, Carmine

    2013-10-30

    In recent decades, oxidative stress has become a focus of interest in most biomedical disciplines and many types of clinical research. Increasing evidence shows that oxidative stress is associated with the pathogenesis of diabetes, obesity, cancer, ageing, inflammation, neurodegenerative disorders, hypertension, apoptosis, cardiovascular diseases, and heart failure. Based on these studies, an emerging concept is that oxidative stress is the "final common pathway" through which the risk factors for several diseases exert their deleterious effects. Oxidative stress causes a complex dysregulation of cell metabolism and cell-cell homeostasis; in particular, oxidative stress plays a key role in the pathogenesis of insulin resistance and β-cell dysfunction. These are the two most relevant mechanisms in the pathophysiology of type 2 diabetes and its vascular complications, the leading cause of death in diabetic patients.

  20. Oxidative Stress in Diabetes: Implications for Vascular and Other Complications

    PubMed Central

    Pitocco, Dario; Tesauro, Manfredi; Alessandro, Rizzi; Ghirlanda, Giovanni; Cardillo, Carmine

    2013-01-01

    In recent decades, oxidative stress has become a focus of interest in most biomedical disciplines and many types of clinical research. Increasing evidence shows that oxidative stress is associated with the pathogenesis of diabetes, obesity, cancer, ageing, inflammation, neurodegenerative disorders, hypertension, apoptosis, cardiovascular diseases, and heart failure. Based on these studies, an emerging concept is that oxidative stress is the “final common pathway” through which the risk factors for several diseases exert their deleterious effects. Oxidative stress causes a complex dysregulation of cell metabolism and cell–cell homeostasis; in particular, oxidative stress plays a key role in the pathogenesis of insulin resistance and β-cell dysfunction. These are the two most relevant mechanisms in the pathophysiology of type 2 diabetes and its vascular complications, the leading cause of death in diabetic patients. PMID:24177571

  1. Nanoparticles, Lung Injury, and the Role of Oxidant Stress

    PubMed Central

    Madl, Amy K.; Plummer, Laurel E.; Carosino, Christopher; Pinkerton, Kent E.

    2015-01-01

    The emergence of engineered nanoscale materials has provided significant advancements in electronic, biomedical, and material science applications. Both engineered nanoparticles and nanoparticles derived from combustion or incidental processes exhibit a range of physical and chemical properties, which have been shown to induce inflammation and oxidative stress in biologic systems. Oxidative stress reflects the imbalance between the generation of reaction oxygen species (ROS) and the biochemical mechanisms to detoxify and repair resulting damage of reactive intermediates. This review examines current research incidental and engineered nanoparticles in terms of their health effects on the lungs and mechanisms by which oxidative stress via physicochemical characteristics influence toxicity or biocompatibility. Although oxidative stress has generally been thought of as an adverse biological outcome, this review will also briefly discuss some of the potential emerging technologies to use nanoparticle-induced oxidative stress to treat disease in a site specific fashion. PMID:24215442

  2. Oxidative stress-induced autophagy: Role in pulmonary toxicity

    SciTech Connect

    Malaviya, Rama; Laskin, Jeffrey D.; Laskin, Debra L.

    2014-03-01

    Autophagy is an evolutionarily conserved catabolic process important in regulating the turnover of essential proteins and in elimination of damaged organelles and protein aggregates. Autophagy is observed in the lung in response to oxidative stress generated as a consequence of exposure to environmental toxicants. Whether autophagy plays role in promoting cell survival or cytotoxicity is unclear. In this article recent findings on oxidative stress-induced autophagy in the lung are reviewed; potential mechanisms initiating autophagy are also discussed. A better understanding of autophagy and its role in pulmonary toxicity may lead to the development of new strategies to treat lung injury associated with oxidative stress. - Highlights: • Exposure to pulmonary toxicants is associated with oxidative stress. • Oxidative stress is known to induce autophagy. • Autophagy is upregulated in the lung following exposure to pulmonary toxicants. • Autophagy may be protective or pathogenic.

  3. Effects of Oxidative Stress on Mesenchymal Stem Cell Biology

    PubMed Central

    2016-01-01

    Mesenchymal stromal/stem cells (MSCs) are multipotent stem cells present in most fetal and adult tissues. Ex vivo culture-expanded MSCs are being investigated for tissue repair and immune modulation, but their full clinical potential is far from realization. Here we review the role of oxidative stress in MSC biology, as their longevity and functions are affected by oxidative stress. In general, increased reactive oxygen species (ROS) inhibit MSC proliferation, increase senescence, enhance adipogenic but reduce osteogenic differentiation, and inhibit MSC immunomodulation. Furthermore, aging, senescence, and oxidative stress reduce their ex vivo expansion, which is critical for their clinical applications. Modulation of sirtuin expression and activity may represent a method to reduce oxidative stress in MSCs. These findings have important implications in the clinical utility of MSCs for degenerative and immunological based conditions. Further study of oxidative stress in MSCs is imperative in order to enhance MSC ex vivo expansion and in vivo engraftment, function, and longevity. PMID:27413419

  4. Skeletal muscle effects of electrostimulation after COPD exacerbation: a pilot study.

    PubMed

    Abdellaoui, A; Préfaut, C; Gouzi, F; Couillard, A; Coisy-Quivy, M; Hugon, G; Molinari, N; Lafontaine, T; Jonquet, O; Laoudj-Chenivesse, D; Hayot, M

    2011-10-01

    Muscle dysfunction is a major problem in chronic obstructive pulmonary disease (COPD), particularly after exacerbations. We thus asked whether neuromuscular electrostimulation (NMES) might be directly useful following an acute exacerbation and if such a therapy decreases muscular oxidative stress and/or alters muscle fibre distribution. A pilot randomised controlled study of NMES lasting 6 weeks was carried out in 15 in-patients (n=9 NMES; n=6 sham) following a COPD exacerbation. Stimulation was delivered to the quadriceps and hamstring muscles (35 Hz). Primary outcomes were quadriceps force and muscle oxidative stress. At the end of the study, quadriceps force improvement was statistically different between groups (p=0.02), with a significant increase only in the NMES group (median (interquartile range) 10 (4.7-11.5) kg; p=0.01). Changes in the 6-min walking distance were statistically different between groups (p=0.008), with a significant increase in the NMES group (165 (125-203) m; p=0.003). NMES did not lead to higher muscle oxidative stress, as indicated by the decrease in total protein carbonylation (p=0.02) and myosin heavy chain carbonylation (p=0.01) levels. Finally, we observed a significant increase in type I fibre proportion in the NMES group. Our study shows that following COPD exacerbation, NMES is effective in counteracting muscle dysfunction and decreases muscle oxidative stress.

  5. Inflammation and oxidative stress are elevated in the brain, blood, and adrenal glands during the progression of post-traumatic stress disorder in a predator exposure animal model.

    PubMed

    Wilson, C Brad; McLaughlin, Leslie D; Nair, Anand; Ebenezer, Philip J; Dange, Rahul; Francis, Joseph

    2013-01-01

    This study sought to analyze specific pathophysiological mechanisms involved in the progression of post-traumatic stress disorder (PTSD) by utilizing an animal model. To examine PTSD pathophysiology, we measured damaging reactive oxygen species and inflammatory cytokines to determine if oxidative stress and inflammation in the brain, adrenal glands, and systemic circulation were upregulated in response to constant stress. Pre-clinical PTSD was induced in naïve, male Sprague-Dawley rats via a predator exposure/psychosocial stress regimen. PTSD group rats were secured in Plexiglas cylinders and placed in a cage with a cat for one hour on days 1 and 11 of a 31-day stress regimen. In addition, PTSD group rats were subjected to psychosocial stress whereby their cage cohort was changed daily. This model has been shown to cause heightened anxiety, exaggerated startle response, impaired cognition, and increased cardiovascular reactivity, all of which are common symptoms seen in humans with PTSD. At the conclusion of the predator exposure/psychosocial stress regimen, the rats were euthanized and their brains were dissected to remove the hippocampus, amygdala, and pre-frontal cortex (PFC), the three areas commonly associated with PTSD development. The adrenal glands and whole blood were also collected to assess systemic oxidative stress. Analysis of the whole blood, adrenal glands, and brain regions revealed oxidative stress increased during PTSD progression. In addition, examination of pro-inflammatory cytokine (PIC) mRNA and protein demonstrated neurological inflammatory molecules were significantly upregulated in the PTSD group vs. controls. These results indicate oxidative stress and inflammation in the brain, adrenal glands, and systemic circulation may play a critical role in the development and further exacerbation of PTSD. Thus, PTSD may not be solely a neurological pathology but may progress as a systemic condition involving multiple organ systems.

  6. Clinical Perspective of Oxidative Stress in Sporadic ALS

    PubMed Central

    D’Amico, Emanuele; Factor-Litvak, Pam; Santella, Regina M.; Mitsumoto, Hiroshi

    2013-01-01

    Sporadic amyotrophic lateral sclerosis (sALS) is one of the most devastating neurological diseases; most patients die within 3 to 4 years after symptom onset. Oxidative stress is a disturbance in the pro-oxidative/anti-oxidative balance favoring the pro-oxidative state. Autopsy and laboratory studies in ALS indicate that oxidative stress plays a major role in motor neuron degeneration and astrocyte dysfunction. Oxidative stress biomarkers in cerebrospinal fluid, plasma, and urine, are elevated, suggesting that abnormal oxidative stress is generated outside of the central nervous system. Our review indicates that agricultural chemicals, heavy metals, military service, professional sports, excessive physical exertion, chronic head trauma, and certain foods might be modestly associated with ALS risk, with a stronger association between risk and smoking. At the cellular level, these factors are all involved in generating oxidative stress. Experimental studies indicate that a combination of insults that induce modest oxidative stress can exert additive deleterious effects on motor neurons, suggesting multiple exposures in real-world environments are important. As the disease progresses, nutritional deficiency, cachexia, psychological stress, and impending respiratory failure may further increase oxidative stress. Moreover, accumulating evidence suggests that ALS is possibly a systemic disease. Laboratory, pathologic, and epidemiologic evidence clearly support the hypothesis that oxidative stress is central in the pathogenic process, particularly in genetically susceptive individuals. If we are to improve ALS treatment, well-designed biochemical and genetic epidemiological studies, combined with a multidisciplinary research approach, are needed and will provide knowledge crucial to our understanding of ALS etiology, pathophysiology, and prognosis. PMID:23797033

  7. Oxidative stress in kidney transplantation: causes, consequences, and potential treatment.

    PubMed

    Nafar, Mohsen; Sahraei, Zahra; Salamzadeh, Jamshid; Samavat, Shiva; Vaziri, Nosartolah D

    2011-11-01

    Oxidative stress is a major mediator of adverse outcomes throughout the course of transplantation. Transplanted kidneys are prone to oxidative stress-mediated injury by pre-transplant and post-transplant conditions that cause reperfusion injury or imbalance between oxidants and antioxidants. Besides adversely affecting the allograft, oxidative stress and its constant companion, inflammation, cause cardiovascular disease, cancer, metabolic syndrome, and other disorders in transplant recipients. Presence and severity of oxidative stress can be assessed by various biomarkers produced from interaction of reactive oxygen species with lipids, proteins, nucleic acids, nitric oxide, glutathione, etc. In addition, expression and activities of redox-sensitive molecules such as antioxidant enzymes can serve as biomarkers of oxidative stress. Via activation of nuclear factor kappa B, oxidative stress promotes inflammation which, in turn, amplifies oxidative stress through reactive oxygen species generation by activated immune cells. Therefore, inflammation markers are indirect indicators of oxidative stress. Many treatment options have been evaluated in studies conducted at different stages of transplantation in humans and animals. These studies have provided useful strategies for use in donors or in organ preservation solutions. However, strategies tested for use in post-transplant phase have been largely inconclusive and controversial. A number of therapeutic options have been exclusively examined in animal models and only a few have been tested in humans. Most of the clinical investigations have been of short duration and have provided no insight into their impact on the long-term survival of transplant patients. Effective treatment of oxidative stress in transplant population remains elusive and awaits future explorations.

  8. Molecular mechanisms of ROS production and oxidative stress in diabetes.

    PubMed

    Newsholme, Philip; Cruzat, Vinicius Fernandes; Keane, Kevin Noel; Carlessi, Rodrigo; de Bittencourt, Paulo Ivo Homem

    2016-12-15

    Oxidative stress and chronic inflammation are known to be associated with the development of metabolic diseases, including diabetes. Oxidative stress, an imbalance between oxidative and antioxidative systems of cells and tissues, is a result of over production of oxidative-free radicals and associated reactive oxygen species (ROS). One outcome of excessive levels of ROS is the modification of the structure and function of cellular proteins and lipids, leading to cellular dysfunction including impaired energy metabolism, altered cell signalling and cell cycle control, impaired cell transport mechanisms and overall dysfunctional biological activity, immune activation and inflammation. Nutritional stress, such as that caused by excess high-fat and/or carbohydrate diets, promotes oxidative stress as evident by increased lipid peroxidation products, protein carbonylation and decreased antioxidant status. In obesity, chronic oxidative stress and associated inflammation are the underlying factors that lead to the development of pathologies such as insulin resistance, dysregulated pathways of metabolism, diabetes and cardiovascular disease through impaired signalling and metabolism resulting in dysfunction to insulin secretion, insulin action and immune responses. However, exercise may counter excessive levels of oxidative stress and thus improve metabolic and inflammatory outcomes. In the present article, we review the cellular and molecular origins and significance of ROS production, the molecular targets and responses describing how oxidative stress affects cell function including mechanisms of insulin secretion and action, from the point of view of possible application of novel diabetic therapies based on redox regulation.

  9. Oxidative stress in the brain causes hypertension via sympathoexcitation.

    PubMed

    Kishi, Takuya; Hirooka, Yoshitaka

    2012-01-01

    Activation of the sympathetic nervous system (SNS) has an important role in the pathogenesis of hypertension, and is determined by the brain. Previous many studies have demonstrated that oxidative stress, mainly produced by angiotensin II type 1 (AT(1)) receptor and nicotinamide adenine dinucleotide phosphate (NAD (P) H) oxidase, in the autonomic brain regions was involved in the activation of the SNS of hypertension. In this concept, we have investigated the role of oxidative stress in the rostral ventrolateral medulla (RVLM), which is known as the cardiovascular center in the brainstem, in the activation of the SNS, and demonstrated that AT(1) receptor and NAD (P) H oxidase-induced oxidative stress in the RVLM causes sympathoexcitation in hypertensive rats. The mechanisms in which brain oxidative stress causes sympathoexcitation have been investigated, such as the interactions with nitric oxide (NO), effects on the signal transduction, or inflammations. Interestingly, the environmental factors of high salt intake and high calorie diet may also increase the oxidative stress in the brain, particularly in the RVLM, thereby activating the central sympathetic outflow and increasing the risk of hypertension. Furthermore, several orally administered AT(1) receptor blockers have been found to cause sympathoinhibition via reduction of oxidative stress through the inhibition of central AT(1) receptor. In conclusion, we must consider that AT(1) receptor and the related oxidative stress production in the brain cause the activation of SNS in hypertension, and that AT(1) receptor in the brain could be novel therapeutic target of the treatments for hypertension.

  10. Oxidative stress and Kawasaki disease: how is oxidative stress involved from the acute stage to the chronic stage?

    PubMed

    Yahata, Tomoyo; Hamaoka, Kenji

    2017-01-01

    Inflammation and oxidative stress are closely related. Further, oxidative stress plays an important role in the pathology of inflammation-based Kawasaki disease. An excessive in vivo production of reactive oxygen species increases oxidative stress in the body, which triggers an endless vicious spiral of inflammation reactions and reactive oxygen metabolites. This presumably forms diffuse vasculitis in the acute phase. Acute inflammation and oxidative stress can be rapidly controlled by treatments; however, they may remain for a long time. This has recently been identified as a problem in the chronic phase of Kawasaki disease. Generally, the presence of vascular inflammation and oxidative stress impairs blood vessels, leading to the onset of atherosclerosis, which is a widely recognized risk. The current discussion focuses on whether the same is valid for blood vessels in the chronic phase of Kawasaki disease.

  11. Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its nucleoside diphosphate kinase activity.

    PubMed

    Peuchant, Evelyne; Bats, Marie-Lise; Moranvillier, Isabelle; Lepoivre, Michel; Guitton, Jérôme; Wendum, Dominique; Lacombe, Marie-Lise; Moreau-Gaudry, François; Boissan, Mathieu; Dabernat, Sandrine

    2017-04-01

    NME1 (nonmetastatic expressed 1) gene, which encodes nucleoside diphosphate kinase (NDPK) A [also known as nonmetastatic clone 23 (NM23)-H1 in humans and NM23-M1 in mice], is a suppressor of metastasis, but several lines of evidence-mostly from plants-also implicate it in the regulation of the oxidative stress response. Here, our aim was to investigate the physiologic relevance of NDPK A with respect to the oxidative stress response in mammals and to study its molecular basis. NME1-knockout mice died sooner, suffered greater hepatocyte injury, and had lower superoxide dismutase activity than did wild-type (WT) mice in response to paraquat-induced acute oxidative stress. Deletion of NME1 reduced total NDPK activity and exacerbated activation of the stress-related MAPK, JNK, in the liver in response to paraquat. In a mouse transformed hepatocyte cell line and in primary cultures of normal human keratinocytes, MAPK activation in response to H2O2 and UVB, respectively, was dampened by expression of NM23-M1/NM23-H1, dependent on its NDPK catalytic activity. Furthermore, excess or depletion of NM23-M1/NM23-H1 NDPK activity did not affect the intracellular bulk concentration of nucleoside di- and triphosphates. NME1-deficient mouse embryo fibroblasts grew poorly in culture, were more sensitive to stress than WT fibroblasts, and did not immortalize, which suggested that they senesce earlier than do WT fibroblasts. Collectively, these results indicate that the NDPK activity of NM23-M1/NM23-H1 protects cells from acute oxidative stress by inhibiting activation of JNK in mammal models.-Peuchant, E., Bats, M.-L., Moranvillier, I., Lepoivre, M., Guitton, J., Wendum, D., Lacombe, M.-L., Moreau-Gaudry, F., Boissan, M., Dabernat, S. Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its nucleoside diphosphate kinase activity.

  12. Aldehyde Dehydrogenases in Cellular Responses to Oxidative/electrophilic Stress

    PubMed Central

    Singh, Surendra; Brocker, Chad; Koppaka, Vindhya; Ying, Chen; Jackson, Brian; Matsumoto, Akiko; Thompson, David C.; Vasiliou, Vasilis

    2013-01-01

    Reactive oxygen species (ROS) are continuously generated within living systems and the inability to manage ROS load leads to elevated oxidative stress and cell damage. Oxidative stress is coupled to the oxidative degradation of lipid membranes, also known as lipid peroxidation. This process generates over 200 types of aldehydes, many of which are highly reactive and toxic. Aldehyde dehydrogenases (ALDHs) metabolize endogenous and exogenous aldehydes and thereby mitigate oxidative/electrophilic stress in prokaryotic and eukaryotic organisms. ALDHs are found throughout the evolutionary gamut, from single celled organisms to complex multicellular species. Not surprisingly, many ALDHs in evolutionarily distant, and seemingly unrelated, species perform similar functions, including protection against a variety of environmental stressors like dehydration and ultraviolet radiation. The ability to act as an ‘aldehyde scavenger’ during lipid peroxidation is another ostensibly universal ALDH function found across species. Up-regulation of ALDHs is a stress response in bacteria (environmental and chemical stress), plants (dehydration, salinity and oxidative stress), yeast (ethanol exposure and oxidative stress), Caenorhabditis elegans (lipid peroxidation) and mammals (oxidative stress and lipid peroxidation). Recent studies have also identified ALDH activity as an important feature of cancer stem cells. In these cells, ALDH expression helps abrogate oxidative stress and imparts resistance against chemotherapeutic agents such as oxazaphosphorine, taxane and platinum drugs. The ALDH superfamily represents a fundamentally important class of enzymes that significantly contributes to the management of electrophilic/oxidative stress within living systems. Mutations in various ALDHs are associated with a variety of pathological conditions in humans, underscoring the fundamental importance of these enzymes in physiological and pathological processes. PMID:23195683

  13. Increased oxidative stress and oxidative DNA damage in non-remission schizophrenia patients.

    PubMed

    Sertan Copoglu, U; Virit, Osman; Hanifi Kokacya, M; Orkmez, Mustafa; Bulbul, Feridun; Binnur Erbagci, A; Semiz, Murat; Alpak, Gokay; Unal, Ahmet; Ari, Mustafa; Savas, Haluk A

    2015-09-30

    Increasing evidence shows that oxidative stress plays a role in the pathophysiology of schizophrenia. But there is not any study which examines the effects of oxidative stress on DNA in schizophrenia patients. Therefore we aimed to assess the oxidative stress levels and oxidative DNA damage in schizophrenia patients with and without symptomatic remission. A total of 64 schizophrenia patients (38 with symptomatic remission and 26 without symptomatic remission) and 80 healthy volunteers were included in the study. 8-hydroxydeoxyguanosine (8-OHdG), total oxidant status (TOS) and total antioxidant status (TAS) were measured in plasma. TOS, oxidative stress index (OSI) and 8-OHdG levels were significantly higher in non-remission schizophrenic (Non-R-Sch) patients than in the controls. TOS and OSI levels were significantly higher in remission schizophrenic (R-Sch) patients than in the controls. TAS level were significantly lower and TOS and OSI levels were significantly higher in R-Sch patients than in Non-R-Sch patients. Despite the ongoing oxidative stress in patients with both R-Sch and Non-R-Sch, oxidative DNA damage was higher in only Non-R-Sch patients compared to controls. It is suggested that oxidative stress can cause the disease via DNA damage, and oxidative stress plays a role in schizophrenia through oxidative DNA damage.

  14. Tyrosine phosphorylation of clathrin heavy chain under oxidative stress.

    PubMed

    Ihara, Yoshito; Yasuoka, Chie; Kageyama, Kan; Wada, Yoshinao; Kondo, Takahito

    2002-09-20

    In mouse pancreatic insulin-producing betaTC cells, oxidative stress due to H(2)O(2) causes tyrosine phosphorylation in various proteins. To identify proteins bearing phosphotyrosine under stress, the proteins were affinity purified using an anti-phosphotyrosine antibody-conjugated agarose column. A protein of 180kDa was identified as clathrin heavy chain (CHC) by electrophoresis and mass spectrometry. Immunoprecipitated CHC showed tyrosine phosphorylation upon H(2)O(2) treatment and the phosphorylation was suppressed by the Src kinase inhibitor, PP2. The phosphorylation status of CHC affected the intracellular localization of CHC and the clathrin-dependent endocytosis of transferrin under oxidative stress. In conclusion, CHC is a protein that is phosphorylated at tyrosine by H(2)O(2) and this phosphorylation status is implicated in the intracellular localization and functions of CHC under oxidative stress. The present study demonstrates that oxidative stress affects intracellular vesicular trafficking via the alteration of clathrin-dependent vesicular trafficking.

  15. Oxidative Stress and Inflammation: What Polyphenols Can Do for Us?

    PubMed Central

    Hussain, Tarique; Yin, Yulong; Blachier, Francois; Tossou, Myrlene C. B.; Rahu, Najma

    2016-01-01

    Oxidative stress is viewed as an imbalance between the production of reactive oxygen species (ROS) and their elimination by protective mechanisms, which can lead to chronic inflammation. Oxidative stress can activate a variety of transcription factors, which lead to the differential expression of some genes involved in inflammatory pathways. The inflammation triggered by oxidative stress is the cause of many chronic diseases. Polyphenols have been proposed to be useful as adjuvant therapy for their potential anti-inflammatory effect, associated with antioxidant activity, and inhibition of enzymes involved in the production of eicosanoids. This review aims at exploring the properties of polyphenols in anti-inflammation and oxidation and the mechanisms of polyphenols inhibiting molecular signaling pathways which are activated by oxidative stress, as well as the possible roles of polyphenols in inflammation-mediated chronic disorders. Such data can be helpful for the development of future antioxidant therapeutics and new anti-inflammatory drugs. PMID:27738491

  16. Oxidative stress responses in Escherichia coli and Salmonella typhimurium.

    PubMed Central

    Farr, S B; Kogoma, T

    1991-01-01

    Oxidative stress is strongly implicated in a number of diseases, such as rheumatoid arthritis, inflammatory bowel disorders, and atherosclerosis, and its emerging as one of the most important causative agents of mutagenesis, tumorigenesis, and aging. Recent progress on the genetics and molecular biology of the cellular responses to oxidative stress, primarily in Escherichia coli and Salmonella typhimurium, is summarized. Bacteria respond to oxidative stress by invoking two distinct stress responses, the peroxide stimulon and the superoxide stimulon, depending on whether the stress is mediated by peroxides or the superoxide anion. The two stimulons each contain a set of more than 30 genes. The expression of a subset of genes in each stimulon is under the control of a positive regulatory element; these genes constitute the OxyR and SoxRS regulons. The schemes of regulation of the two regulons by their respective regulators are reviewed in detail, and the overlaps of these regulons with other stress responses such as the heat shock and SOS responses are discussed. The products of Oxy-R- and SoxRS-regulated genes, such as catalases and superoxide dismutases, are involved in the prevention of oxidative damage, whereas others, such as endonuclease IV, play a role in the repair of oxidative damage. The potential roles of these and other gene products in the defense against oxidative damage in DNA, proteins, and membranes are discussed in detail. A brief discussion of the similarities and differences between oxidative stress responses in bacteria and eukaryotic organisms concludes this review. PMID:1779927

  17. Chronic oxidative stress after irradiation: an unproven hypothesis

    PubMed Central

    Cohen, Samuel R; Cohen, Eric P

    2012-01-01

    Injury and organ failure after irradiation of late-responding tissues is a substantial problem in radiation oncology and a major threat after accidental or belligerent exposures. The mechanisms of injury may include death of clonogens, vascular injury, activation of cytokine networks, and/or chronic oxidative stress. Knowledge of mechanisms may guide optimal use of mitigators. The hypothesis of chronic oxidative stress as a mechanism of late radiation injury has received much attention. We review herein the published evidence for chronic oxidative stress in vivo, and for use of antioxidants as mitigators of normal tissue radiation injury. We conclude that there is only indirect evidence for chronic oxidative stress after irradiation, and there are only limited published reports of mitigation by antioxidants. We did not find a differentiation of persistent markers of oxidative stress from an ongoing production of oxygen radicals. It is thus unproven that chronic oxidative stress plays a major role in causing radiation injury and organ failure in late-responding tissues. Further investigation is justified, to identify persistent oxidative stress and to identify optimal mitigators of radiation injury. PMID:23245910

  18. Potential role of punicalagin against oxidative stress induced testicular damage

    PubMed Central

    Rao, Faiza; Tian, Hui; Li, Wenqing; Hung, Helong; Sun, Fei

    2016-01-01

    Punicalagin is isolated from pomegranate and widely used for the treatment of different diseases in Chinese traditional medicine. This study aimed to evaluate the effect of Punicalagin (purity ≥98%) on oxidative stress induced testicular damage and its effect on fertility. We detected the antioxidant potential of punicalagin in lipopolysaccharide (LPS) induced oxidative stress damage in testes, also tried to uncover the boosting fertility effect of Punicalagin (PU) against oxidative stress-induced infertility. Results demonstrated that 9 mg kg−1 for 7 days treatment significantly decreases LPS induced oxidative damage in testes and nitric oxide production. The administration of oxidative stress resulted in a significant reduction in testes antioxidants GSH, T-SOD, and CAT raised LPO, but treatment with punicalagin for 7 days increased antioxidant defense GSH, T-SOD, and CAT by the end of the experiment and reduced LPO level as well. PU also significantly activates Nrf2, which is involved in regulation of antioxidant defense systems. Hence, the present research categorically elucidates the protective effect of punicalagin against LPS induced oxidative stress induced perturbation in the process of spermatogenesis and significantly increased sperm health and number. Moreover, fertility success significantly decreased in LPS-injected mice compared to controls. Mice injected with LPS had fertility indices of 12.5%, while others treated with a combination of PU + LPS exhibited 75% indices. By promoting fertility and eliminating oxidative stress and inflammation, PU may be a useful nutrient for the treatment of infertility. PMID:26763544

  19. Oxidative stress and metabolic disorders: Pathogenesis and therapeutic strategies.

    PubMed

    Rani, Vibha; Deep, Gagan; Singh, Rakesh K; Palle, Komaraiah; Yadav, Umesh C S

    2016-03-01

    Increased body weight and metabolic disorder including insulin resistance, type 2 diabetes and cardiovascular complications together constitute metabolic syndrome. The pathogenesis of metabolic syndrome involves multitude of factors. A number of studies however indicate, with some conformity, that oxidative stress along with chronic inflammatory condition pave the way for the development of metabolic diseases. Oxidative stress, a state of lost balance between the oxidative and anti-oxidative systems of the cells and tissues, results in the over production of oxidative free radicals and reactive oxygen species (ROS). Excessive ROS generated could attack the cellular proteins, lipids and nucleic acids leading to cellular dysfunction including loss of energy metabolism, altered cell signalling and cell cycle control, genetic mutations, altered cellular transport mechanisms and overall decreased biological activity, immune activation and inflammation. In addition, nutritional stress such as that caused by high fat high carbohydrate diet also promotes oxidative stress as evident by increased lipid peroxidation products, protein carbonylation, and decreased antioxidant system and reduced glutathione (GSH) levels. These changes lead to initiation of pathogenic milieu and development of several chronic diseases. Studies suggest that in obese person oxidative stress and chronic inflammation are the important underlying factors that lead to development of pathologies such as carcinogenesis, obesity, diabetes, and cardiovascular diseases through altered cellular and nuclear mechanisms, including impaired DNA damage repair and cell cycle regulation. Here we discuss the aspects of metabolic disorders-induced oxidative stress in major pathological conditions and strategies for their prevention and therapy.

  20. Potential role of punicalagin against oxidative stress induced testicular damage.

    PubMed

    Rao, Faiza; Tian, Hui; Li, Wenqing; Hung, Helong; Sun, Fei

    2016-01-01

    Punicalagin is isolated from pomegranate and widely used for the treatment of different diseases in Chinese traditional medicine. This study aimed to evaluate the effect of Punicalagin (purity ≥98%) on oxidative stress induced testicular damage and its effect on fertility. We detected the antioxidant potential of punicalagin in lipopolysaccharide (LPS) induced oxidative stress damage in testes, also tried to uncover the boosting fertility effect of Punicalagin (PU) against oxidative stress-induced infertility. Results demonstrated that 9 mg kg-1 for 7 days treatment significantly decreases LPS induced oxidative damage in testes and nitric oxide production. The administration of oxidative stress resulted in a significant reduction in testes antioxidants GSH, T-SOD, and CAT raised LPO, but treatment with punicalagin for 7 days increased antioxidant defense GSH, T-SOD, and CAT by the end of the experiment and reduced LPO level as well. PU also significantly activates Nrf2, which is involved in regulation of antioxidant defense systems. Hence, the present research categorically elucidates the protective effect of punicalagin against LPS induced oxidative stress induced perturbation in the process of spermatogenesis and significantly increased sperm health and number. Moreover, fertility success significantly decreased in LPS-injected mice compared to controls. Mice injected with LPS had fertility indices of 12.5%, while others treated with a combination of PU + LPS exhibited 75% indices. By promoting fertility and eliminating oxidative stress and inflammation, PU may be a useful nutrient for the treatment of infertility.

  1. Oxidative stress and psychological functioning among medical students

    PubMed Central

    Srivastava, Rani; Batra, Jyoti

    2014-01-01

    Background: Oxidative stress has gained attention recently in behavioral medicine and has been reported to be associated with various psychological disturbances and their prognoses. Objectives: Study aims to evaluate the oxidative stress (malonylaldehyde (MDA) levels) and its relation with psychological factors (dimensions of personality, levels of anxiety, stress, and depression) among medical/paramedical students of 1st and 3rd year). Materials and Methods: A total of 150 students; 75 from 1st year (2010–2011) and75 from 3rd year (2009–2010); of medical and paramedical background were assessed on level of MDA (oxidative stress) and personality variables, that is, level of anxiety, stress, and depression. These psychological variables were correlated with the level of their oxidative stress. Results: Findings revealed that both groups are influenced by oxidative stress and their psychological variables are also compatible in order to confirm their vulnerabilities to stress. Conclusions: Stress in 3rd year students was significantly higher and it was noted that it adversely affects the psychological parameters. Hence, special attention on mental health aspect in these students may be given. PMID:25788802

  2. Interrelated role of cigarette smoking, oxidative stress, and immune response in COPD and corresponding treatments.

    PubMed

    Zuo, Li; He, Feng; Sergakis, Georgianna G; Koozehchian, Majid S; Stimpfl, Julia N; Rong, Yi; Diaz, Philip T; Best, Thomas M

    2014-08-01

    Cigarette smoking (CS) can impact the immune system and induce pulmonary disorders such as chronic obstructive pulmonary disease (COPD), which is currently the fourth leading cause of chronic morbidity and mortality worldwide. Accordingly, the most significant risk factor associated with COPD is exposure to cigarette smoke. The purpose of the present study is to provide an updated overview of the literature regarding the effect of CS on the immune system and lungs, the mechanism of CS-induced COPD and oxidative stress, as well as the available and potential treatment options for CS-induced COPD. An extensive literature search was conducted on the PubMed/Medline databases to review current COPD treatment research, available in the English language, dating from 1976 to 2014. Studies have investigated the mechanism by which CS elicits detrimental effects on the immune system and pulmonary function through the use of human and animal subjects. A strong relationship among continued tobacco use, oxidative stress, and exacerbation of COPD symptoms is frequently observed in COPD subjects. In addition, therapeutic approaches emphasizing smoking cessation have been developed, incorporating counseling and nicotine replacement therapy. However, the inability to reverse COPD progression establishes the need for improved preventative and therapeutic strategies, such as a combination of intensive smoking cessation treatment and pharmaceutical therapy, focusing on immune homeostasis and redox balance. CS initiates a complex interplay between oxidative stress and the immune response in COPD. Therefore, multiple approaches such as smoking cessation, counseling, and pharmaceutical therapies targeting inflammation and oxidative stress are recommended for COPD treatment.

  3. Systemic inflammatory changes and increased oxidative stress in rural Indian women cooking with biomass fuels.

    PubMed

    Dutta, Anindita; Ray, Manas Ranjan; Banerjee, Anirban

    2012-06-15

    The study was undertaken to investigate whether regular cooking with biomass aggravates systemic inflammation and oxidative stress that might result in increase in the risk of developing cardiovascular disease (CVD) in rural Indian women compared to cooking with a cleaner fuel like liquefied petroleum gas (LPG). A total of 635 women (median age 36 years) who cooked with biomass and 452 age-matched control women who cooked with LPG were enrolled. Serum interleukin-6 (IL-6), C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α) and interleukin-8 (IL-8) were measured by ELISA. Generation of reactive oxygen species (ROS) by leukocytes was measured by flow cytometry, and erythrocytic superoxide dismutase (SOD) was measured by spectrophotometry. Hypertension was diagnosed following the Seventh Report of the Joint Committee. Tachycardia was determined as pulse rate >100 beats per minute. Particulate matter of diameter less than 10 and 2.5 μm (PM₁₀ and PM₂.₅, respectively) in cooking areas was measured using real-time aerosol monitor. Compared with control, biomass users had more particulate pollution in indoor air, their serum contained significantly elevated levels of IL-6, IL-8, TNF-α and CRP, and ROS generation was increased by 37% while SOD was depleted by 41.5%, greater prevalence of hypertension and tachycardia compared to their LPG-using neighbors. PM₁₀ and PM₂.₅ levels were positively associated with markers of inflammation, oxidative stress and hypertension. Inflammatory markers correlated with raised blood pressure. Cooking with biomass exacerbates systemic inflammation, oxidative stress, hypertension and tachycardia in poor women cooking with biomass fuel and hence, predisposes them to increased risk of CVD development compared to the controls. Systemic inflammation and oxidative stress may be the mechanistic factors involved in the development of CVD.

  4. The Role of Flavonoids on Oxidative Stress in Epilepsy

    PubMed Central

    Diniz, Tâmara Coimbra; Silva, Juliane Cabral; de Lima-Saraiva, Sarah Raquel Gomes; Ribeiro, Fernanda Pires Rodrigues de Almeida; Pacheco, Alessandra Gomes Marques; de Freitas, Rivelilson Mendes; Quintans-Júnior, Lucindo José; Quintans, Jullyana de Souza Siqueira; Mendes, Rosemairy Luciane; Almeida, Jackson Roberto Guedes da Silva

    2015-01-01

    Backgrounds. Oxidative stress can result from excessive free-radical production and it is likely implicated as a possible mechanism involved in the initiation and progression of epileptogenesis. Flavonoids can protect the brain from oxidative stress. In the central nervous system (CNS) several flavonoids bind to the benzodiazepine site on the GABAA-receptor resulting in anticonvulsive effects. Objective. This review provides an overview about the role of flavonoids in oxidative stress in epilepsy. The mechanism of action of flavonoids and its relation to the chemical structure is also discussed. Results/Conclusions. There is evidence that suggests that flavonoids have potential for neuroprotection in epilepsy. PMID:25653736

  5. Severe Life Stress and Oxidative Stress in the Brain: From Animal Models to Human Pathology

    PubMed Central

    Jaquet, Vincent; Trabace, Luigia; Krause, Karl-Heinz

    2013-01-01

    Abstract Significance: Severe life stress (SLS), as opposed to trivial everyday stress, is defined as a serious psychosocial event with the potential of causing an impacting psychological traumatism. Recent Advances: Numerous studies have attempted to understand how the central nervous system (CNS) responds to SLS. This response includes a variety of morphological and neurochemical modifications; among them, oxidative stress is almost invariably observed. Oxidative stress is defined as disequilibrium between oxidant generation and the antioxidant response. Critical Issues: In this review, we discuss how SLS leads to oxidative stress in the CNS, and how the latter impacts pathophysiological outcomes. We also critically discuss experimental methods that measure oxidative stress in the CNS. The review covers animal models and human observations. Animal models of SLS include sleep deprivation, maternal separation, and social isolation in rodents, and the establishment of hierarchy in non-human primates. In humans, SLS, which is caused by traumatic events such as child abuse, war, and divorce, is also accompanied by oxidative stress in the CNS. Future Directions: The outcome of SLS in humans ranges from resilience, over post-traumatic stress disorder, to development of chronic mental disorders. Defining the sources of oxidative stress in SLS might in the long run provide new therapeutic avenues. Antioxid. Redox Signal. 18, 1475–1490. PMID:22746161

  6. Mitochondrial metabolism mediates oxidative stress and inflammation in fatty liver

    PubMed Central

    Satapati, Santhosh; Kucejova, Blanka; Duarte, Joao A.G.; Fletcher, Justin A.; Reynolds, Lacy; Sunny, Nishanth E.; He, Tianteng; Nair, L. Arya; Livingston, Kenneth; Fu, Xiaorong; Merritt, Matthew E.; Sherry, A. Dean; Malloy, Craig R.; Shelton, John M.; Lambert, Jennifer; Parks, Elizabeth J.; Corbin, Ian; Magnuson, Mark A.; Browning, Jeffrey D.; Burgess, Shawn C.

    2015-01-01

    Mitochondria are critical for respiration in all tissues; however, in liver, these organelles also accommodate high-capacity anaplerotic/cataplerotic pathways that are essential to gluconeogenesis and other biosynthetic activities. During nonalcoholic fatty liver disease (NAFLD), mitochondria also produce ROS that damage hepatocytes, trigger inflammation, and contribute to insulin resistance. Here, we provide several lines of evidence indicating that induction of biosynthesis through hepatic anaplerotic/cataplerotic pathways is energetically backed by elevated oxidative metabolism and hence contributes to oxidative stress and inflammation during NAFLD. First, in murine livers, elevation of fatty acid delivery not only induced oxidative metabolism, but also amplified anaplerosis/cataplerosis and caused a proportional rise in oxidative stress and inflammation. Second, loss of anaplerosis/cataplerosis via genetic knockdown of phosphoenolpyruvate carboxykinase 1 (Pck1) prevented fatty acid–induced rise in oxidative flux, oxidative stress, and inflammation. Flux appeared to be regulated by redox state, energy charge, and metabolite concentration, which may also amplify antioxidant pathways. Third, preventing elevated oxidative metabolism with metformin also normalized hepatic anaplerosis/cataplerosis and reduced markers of inflammation. Finally, independent histological grades in human NAFLD biopsies were proportional to oxidative flux. Thus, hepatic oxidative stress and inflammation are associated with elevated oxidative metabolism during an obesogenic diet, and this link may be provoked by increased work through anabolic pathways. PMID:26571396

  7. Elevated CO₂ mitigates drought and temperature-induced oxidative stress differently in grasses and legumes.

    PubMed

    AbdElgawad, Hamada; Farfan-Vignolo, Evelyn Roxana; de Vos, Dirk; Asard, Han

    2015-02-01

    Increasing atmospheric CO2 will affect plant growth, including mitigation of stress impact. Such effects vary considerably between species-groups. Grasses (Lolium perenne, Poa pratensis) and legumes (Medicago lupulina, Lotus corniculatus) were subjected to drought, elevated temperature and elevated CO2. Drought inhibited plant growth, photosynthesis and stomatal conductance, and induced osmolytes and antioxidants in all species. In contrast, oxidative damage was more strongly induced in the legumes than in the grasses. Warming generally exacerbated drought effects, whereas elevated CO2 reduced stress impact. In the grasses, photosynthesis and chlorophyll levels were more protected by CO2 than in the legumes. Oxidative stress parameters (lipid peroxidation, H2O2 levels), on the other hand, were generally more reduced in the legumes. This is consistent with changes in molecular antioxidants, which were reduced by elevated CO2 in the grasses, but not in the legumes. Antioxidant enzymes decreased similarly in both species-groups. The ascorbate-glutathione cycle was little affected by drought and CO2. Overall, elevated CO2 reduced drought effects in grasses and legumes, and this mitigation was stronger in the legumes. This is possibly explained by stronger reduction in H2O2 generation (photorespiration and NADPH oxidase), and a higher availability of molecular antioxidants. The grass/legume-specificity was supported by principal component analysis.

  8. Protective mechanisms of Cucumis sativus in diabetes-related modelsof oxidative stress and carbonyl stress

    PubMed Central

    Heidari, Himan; Kamalinejad, Mohammad; Noubarani, Maryam; Rahmati, Mokhtar; Jafarian, Iman; Adiban, Hasan; Eskandari, Mohammad Reza

    2016-01-01

    Introduction: Oxidative stress and carbonyl stress have essential mediatory roles in the development of diabetes and its related complications through increasing free radicals production and impairing antioxidant defense systems. Different chemical and natural compounds have been suggested for decreasing such disorders associated with diabetes. The objectives of the present study were to investigate the protective effects of Cucumis sativus (C. sativus) fruit (cucumber) in oxidative and carbonyl stress models. These diabetes-related models with overproduction of reactive oxygen species (ROS) and reactive carbonyl species (RCS) simulate conditions observed in chronic hyperglycemia. Methods: Cytotoxicity induced by cumene hydroperoxide (oxidative stress model) or glyoxal (carbonyl stress model) were measured and the protective effects of C. sativus were evaluated using freshly isolated rat hepatocytes. Results: Aqueous extract of C. sativus fruit (40 μg/mL) prevented all cytotoxicity markers in both the oxidative and carbonyl stress models including cell lysis, ROS formation, membrane lipid peroxidation, depletion of glutathione, mitochondrial membrane potential decline, lysosomal labialization, and proteolysis. The extract also protected hepatocytes from protein carbonylation induced by glyoxal. Our results indicated that C. sativus is able to prevent oxidative stress and carbonyl stress in the isolated hepatocytes. Conclusion: It can be concluded that C. sativus has protective effects in diabetes complications and can be considered a safe and suitable candidate for decreasing the oxidative stress and carbonyl stress that is typically observed in diabetes mellitus. PMID:27340622

  9. Role of oxidative stress & transient receptor potential in chronic obstructive pulmonary disease

    PubMed Central

    Bose, Protiti; Bathri, Rashmi; Kumar, Lalit; Vijayan, V.K.; Maudar, K.K.

    2015-01-01

    Chronic obstructive pulmonary disease (COPD) affect millions of people worldwide and is known to be one of the leading causes of death. The highly sensitive airways protect themselves from irritants by cough and sneeze which propel endogenous and exogenous substances to minimize airway noxious effects. One noxious effect of these substances is activation of peripheral sensory nerve endings of nociceptor neurons innervating these airways lining thus transmitting dangerous signals from the environment to the central nervous system (CNS). Nociceptor neurons include transient receptor potential (TRP) ion channels, especially the vanilloid and ankyrin subfamilies, TRPV1/A1 which can be activated by noxious chemical challenges in models of airways disease. As oxidative stress may activate airways sensory neurons and contribute to COPD exacerbations we sought to review the role that TRP channel activation by oxidative signals may have on airway responses. It would be prudent to target the TRP channels with antagonists and lower systemic oxidative stress with agents that can modulate TRP expression and boost the endogenous levels of antioxidants for treatment and management of COPD. PMID:26458340

  10. Reduced resistance to oxidative stress during reproduction as a cost of early-life stress.

    PubMed

    Zimmer, Cédric; Spencer, Karen A

    2015-05-01

    Stress exposure during early-life development can have long-term consequences for a variety of biological functions including oxidative stress. The link between early-life stress and oxidative balance is beginning to be explored and previous studies have focused on this link in adult non-breeding or immature individuals. However, as oxidative stress is considered as the main physiological mechanism underlying the trade-off between self-maintenance and investment in reproduction, it is necessary to look at the consequences of early-life stress on oxidative status during reproduction. Here, we investigated the effects of exposure to pre- and/or post-natal stress on oxidative balance during reproduction under benign or stressful environmental conditions in an avian model species, the Japanese quail. We determined total antioxidant status (TAS), total oxidant status (TOS) and resistance to a free-radical attack in individual exposed to pre-natal stress, post-natal stress or both and in control individuals exposed to none of the stressors. TAS levels decreased over time in all females that reproduced under stressful conditions. TOS decreased between the beginning and the end of reproductive period in pre-natal control females. In all females, resistance to a free-radical attack decreased over the reproductive event but this decrease was more pronounced in females from a pre-natal stress development. Our results suggest that pre-natal stress may be associated with a higher cost of reproduction in terms of oxidative stress. These results also confirm that early-life stress can be associated with both benefits and costs depending of the life-history stage or environmental context.

  11. Relationships between adult asthma and oxidative stress markers and pH in exhaled breath condensate: a systematic review.

    PubMed

    Aldakheel, F M; Thomas, P S; Bourke, J E; Matheson, M C; Dharmage, S C; Lowe, A J

    2016-06-01

    Oxidative stress has a recognized role in the pathophysiology of asthma. Recently, interest has increased in the assessment of pH and airway oxidative stress markers. Collection of exhaled breath condensate (EBC) and quantification of biomarkers in breath samples can potentially indicate lung disease activity and help in the study of airway inflammation, and asthma severity. Levels of oxidative stress markers in the EBC have been systematically evaluated in children with asthma; however, there is no such systematic review conducted for adult asthma. A systematic review of oxidative stress markers measured in EBC of adult asthma was conducted, and studies were identified by searching MEDLINE and SCOPUS databases. Sixteen papers met the inclusion criteria. Concentrations of exhaled hydrogen ions, nitric oxide products, hydrogen peroxide and 8-isoprostanes were generally elevated and related to lower lung function tests in adults with asthma compared to healthy subjects. Assessment of EBC markers may be a noninvasive approach to evaluate airway inflammation, exacerbations, and disease severity of asthma, and to monitor the effectiveness of anti-inflammatory treatment regimens. Longitudinal studies, using standardized analytical techniques for EBC collection, are required to establish reference values for the interpretation of EBC markers in the context of asthma.

  12. Postprandial Dysmetabolism and Oxidative Stress in Type 2 Diabetes: Pathogenetic Mechanisms and Therapeutic Strategies.

    PubMed

    Sottero, Barbara; Gargiulo, Simona; Russo, Isabella; Barale, Cristina; Poli, Giuseppe; Cavalot, Franco

    2015-09-01

    Postprandial dysmetabolism in type 2 diabetes (T2D) is known to impact the progression and evolution of this complex disease process. However, the underlying pathogenetic mechanisms still require full elucidation to provide guidance for disease prevention and treatment. This review focuses on the marked redox changes and inflammatory stimuli provoked by the spike in blood glucose and lipids in T2D individuals after meals. All the causes of exacerbated postprandial oxidative stress in T2D were analyzed, also considering the consequence of enhanced inflammation on vascular damage. Based on this in-depth analysis, current strategies of prevention and pharmacologic management of T2D were critically reexamined with particular emphasis on their potential redox-related rationale.

  13. Oxidative stress induces senescence in human mesenchymal stem cells

    SciTech Connect

    Brandl, Anita; Meyer, Matthias; Bechmann, Volker; Nerlich, Michael; Angele, Peter

    2011-07-01

    Mesenchymal stem cells (MSCs) contribute to tissue repair in vivo and form an attractive cell source for tissue engineering. Their regenerative potential is impaired by cellular senescence. The effects of oxidative stress on MSCs are still unknown. Our studies were to investigate into the proliferation potential, cytological features and the telomere linked stress response system of MSCs, subject to acute or prolonged oxidant challenge with hydrogen peroxide. Telomere length was measured using the telomere restriction fragment assay, gene expression was determined by rtPCR. Sub-lethal doses of oxidative stress reduced proliferation rates and induced senescent-morphological features and senescence-associated {beta}-galactosidase positivity. Prolonged low dose treatment with hydrogen peroxide had no effects on cell proliferation or morphology. Sub-lethal and prolonged low doses of oxidative stress considerably accelerated telomere attrition. Following acute oxidant insult p21 was up-regulated prior to returning to initial levels. TRF1 was significantly reduced, TRF2 showed a slight up-regulation. SIRT1 and XRCC5 were up-regulated after oxidant insult and expression levels increased in aging cells. Compared to fibroblasts and chondrocytes, MSCs showed an increased tolerance to oxidative stress regarding proliferation, telomere biology and gene expression with an impaired stress tolerance in aged cells.

  14. Crosstalk between oxidative and nitrosative stress and arterial stiffness.

    PubMed

    Mozos, Ioana; Luca, Constantin Tudor

    2017-02-01

    Arterial stiffness, the expression of reduced arterial elasticity, is an effective predictor of cardiovascular disorders. Oxidative stress is an imbalance between exposure to toxic reactive oxygen species (ROS) and antioxidant systems. The increase in reactive nitrogen species (RNS) is termed nitrosative stress. We review the main mechanisms and products linking arterial stiffness with oxidative and nitrosative stress in several disorders, focusing on recent experimental and clinical data, and the mechanisms explaining benefits of antioxidant therapy. Oxidative and nitrosative stress play important roles in arterial stiffness elevation in several disorders, including diabetes mellitus, hypertension, metabolic syndrome, obesity, peripheral arterial disease, chronic obstructive pulmonary disease, systemic lupus erythematosus, thalassemia, Kawasaki disease and malignant disorders. Oxidative and nitrosative stress are responsible for endothelial dysfunction due to uncoupling of the nitric oxide synthase, oxidative damage to lipids, proteins and DNA in vascular endothelial cells, associated with inflammation, arteriosclerosis and atherosclerosis. Regular physical exercise, caloric restriction, red wine, statins, sartans, metformin, oestradiol, curcumin and combinations of antioxidant vitamins are therapeutic strategies that may decrease arterial stiffness and oxidative stress thus reducing the risk of cardiovascular events. ROS and RNS represent potential therapeutic targets for preventing progression of arterial stiffness.

  15. Oxidative stress in aspic vipers facing pregnancy and water constraints.

    PubMed

    Stier, Antoine; Dupoué, Andréaz; Picard, Damien; Angelier, Frédéric; Brischoux, François; Lourdais, Olivier

    2017-03-14

    The physiological mechanisms underlying the 'cost of reproduction' remain under debate, though oxidative stress has emerged as a potential candidate. The 'oxidative cost of reproduction' has received considerable attention with regards to food and antioxidant availability, however the limitation of water availability has thus far been neglected. In this study we experimentally examined the combined effect of pregnancy and water-deprivation on oxidative status in a viviparous snake (Vipera aspis), a species naturally exposed to periods of water and food deprivation. We predicted a cumulative effect of pregnancy and dehydration on oxidative stress levels. Our results support the occurrence of an oxidative cost of reproduction since we found higher oxidative damage levels in pregnant females than in non-reproductive individuals, despite an up-regulation of antioxidant defences. Surprisingly, water-deprivation was associated with an up-regulation of antioxidant defences, and did not increase oxidative damage, either alone or in combination with reproduction.

  16. Osmotic and oxidative/nitrosative stress in ammonia toxicity and hepatic encephalopathy.

    PubMed

    Görg, Boris; Schliess, Freimut; Häussinger, Dieter

    2013-08-15

    Hepatic encephalopathy (HE) is a neuropsychiatric complication of acute or chronic liver failure. Currently, HE in cirrhotic patients is seen as a clinical manifestation of a low grade cerebral edema which exacerbates in response to a variety of precipitating factors after an ammonia-induced exhaustion of the volume-regulatory capacity of the astrocyte. Astrocyte swelling triggers a complex signaling cascade which relies on NMDA receptor activation, elevation of intracellular Ca(2+) concentration and prostanoid-driven glutamate exocytosis, which result in increased formation of reactive nitrogen and oxygen species (RNOS) through activation of NADPH oxidase and nitric oxide synthase. Since RNOS in turn promote astrocyte swelling, a self-amplifying signaling loop between osmotic- and oxidative stress ensues, which triggers a variety of downstream consequences. These include protein tyrosine nitration (PTN), oxidation of RNA, mobilization of zinc, alterations in intra- and intercellular signaling and multiple effects on gene transcription. Whereas PTN can affect the function of a variety of proteins, such as glutamine synthetase, oxidized RNA may affect local protein synthesis at synapses, thereby potentially interfering with protein synthesis-dependent memory formation. PTN and RNA oxidation are also found in post mortem human cerebral cortex of cirrhotic patients with HE but not in those without HE, thereby confirming a role for oxidative stress in the pathophysiology of HE. Evidence derived from animal experiments and human post mortem brain tissue also indicates an up-regulation of microglia activation markers in the absence of increased synthesis of pro-inflammatory cytokines. However, the role of activated microglia in the pathophysiology of HE needs to be worked out in more detail. Most recent observations made in whole genome micro-array analyses of post mortem human brain tissue point to a hitherto unrecognized activation of multiple anti

  17. Oxidative stress in juvenile chinook salmon, Oncorhynchus tshawytscha (Walbaum)

    USGS Publications Warehouse

    Welker, T.L.; Congleton, J.L.

    2004-01-01

    Juvenile chinook salmon, Oncorhynchus tshawytscha (Walbaum), were held in 8-11??C freshwater, starved for 3 days and subjected to a low-water stressor to determine the relationship between the general stress response and oxidative stress. Lipid peroxidation (LPO) levels (lipid hydroperoxides) were measured in kidney, liver and brain samples taken at the beginning of the experiment (0-h unstressed controls) and at 6, 24 and 48 h after application of a continuous low-water stressor. Tissue samples were also taken at 48 h from fish that had not been exposed to the stressor (48-h unstressed controls). Exposure to the low-water stressor affected LPO in kidney and brain tissues. In kidney, LPO decreased 6 h after imposition of the stressor; similar but less pronounced decreases also occurred in the liver and brain. At 48 h, LPO increased (in comparison with 6-h stressed tissues) in the kidney and brain. In comparison with 48-h unstressed controls, LPO levels were higher in the kidney and brain of stressed fish. Although preliminary, results suggest that stress can cause oxidative tissue damage in juvenile chinook salmon. Measures of oxidative stress have shown similar responses to stress in mammals; however, further research is needed to determine the extent of the stress-oxidative stress relationship and the underlying physiological mechanisms in fish.

  18. Futile cycling increases sensitivity toward oxidative stress in Escherichia coli

    PubMed Central

    Adolfsen, Kristin J.; Brynildsen, Mark P.

    2015-01-01

    Reactive oxygen species (ROS) are toxic molecules utilized by the immune system to combat invading pathogens. Recent evidence suggests that inefficiencies in ATP production or usage can lead to increased endogenous ROS production and sensitivity to oxidative stress in bacteria. With this as inspiration, and knowledge that ATP is required for a number of DNA repair mechanisms, we hypothesized that futile cycling would be an effective way to increase sensitivity to oxidative stress. We developed a mixed integer linear optimization framework to identify experimentally-tractable futile cycles, and confirmed metabolic modeling predictions that futile cycling depresses growth rate, and increases both O2 consumption and ROS production per biomass generated. Further, intracellular ATP was decreased and sensitivity to oxidative stress increased in all actively cycling strains compared to their catalytically inactive controls. This research establishes a fundamental connection between ATP metabolism, endogenous ROS production, and tolerance toward oxidative stress in bacteria. PMID:25732623

  19. Systemic inflammatory changes and increased oxidative stress in rural Indian women cooking with biomass fuels

    SciTech Connect

    Dutta, Anindita; Ray, Manas Ranjan; Banerjee, Anirban

    2012-06-15

    The study was undertaken to investigate whether regular cooking with biomass aggravates systemic inflammation and oxidative stress that might result in increase in the risk of developing cardiovascular disease (CVD) in rural Indian women compared to cooking with a cleaner fuel like liquefied petroleum gas (LPG). A total of 635 women (median age 36 years) who cooked with biomass and 452 age-matched control women who cooked with LPG were enrolled. Serum interleukin-6 (IL-6), C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α) and interleukin-8 (IL-8) were measured by ELISA. Generation of reactive oxygen species (ROS) by leukocytes was measured by flow cytometry, and erythrocytic superoxide dismutase (SOD) was measured by spectrophotometry. Hypertension was diagnosed following the Seventh Report of the Joint Committee. Tachycardia was determined as pulse rate > 100 beats per minute. Particulate matter of diameter less than 10 and 2.5 μm (PM{sub 10} and PM{sub 2.5}, respectively) in cooking areas was measured using real-time aerosol monitor. Compared with control, biomass users had more particulate pollution in indoor air, their serum contained significantly elevated levels of IL-6, IL-8, TNF-α and CRP, and ROS generation was increased by 37% while SOD was depleted by 41.5%, greater prevalence of hypertension and tachycardia compared to their LPG-using neighbors. PM{sub 10} and PM{sub 2.5} levels were positively associated with markers of inflammation, oxidative stress and hypertension. Inflammatory markers correlated with raised blood pressure. Cooking with biomass exacerbates systemic inflammation, oxidative stress, hypertension and tachycardia in poor women cooking with biomass fuel and hence, predisposes them to increased risk of CVD development compared to the controls. Systemic inflammation and oxidative stress may be the mechanistic factors involved in the development of CVD. -- Highlights: ► Effect of chronic biomass smoke exposure on

  20. Flowers of Clerodendrum volubile exacerbate immunomodulation by suppressing phagocytic oxidative burst and modulation of COX-2 activity.

    PubMed

    Erukainure, Ochuko L; Mesaik, Ahmed M; Muhammad, Aliyu; Chukwuma, Chika I; Manhas, Neha; Singh, Parvesh; Aremu, Oluwole S; Islam, Md Shahidul

    2016-10-01

    The immunomodulatory potentials of the crude methanolic extract and fractions [n-hexane (Hex), n-dichloromethane (DCM), ethyl acetate (EtOAc) and n-butanol (BuOH)] of Clerodendrum volubile flowers were investigated on whole blood phagocytic oxidative burst using luminol-amplified chemiluminescence technique. They were also investigated for their free radicals scavenging activities. The DCM fraction showed significant (p<0.05) anti-oxidative burst and free radical scavenging activities indicating high immunomodulatory and antioxidant potencies respectively. Cytotoxicity assay of the DCM fraction revealed a cytotoxic effect on CC-1 normal cell line. GCMS analysis revealed the presence of triacetin; 3,6-dimethyl-3-octanol; 2R - Acetoxymethyl-1,3,3-trimethtyl - 4t - (3-methyl-2-buten-1-yl) - 1c - cyclohexanol and Stigmastan - 3,5-diene in DCM fraction. These compounds were docked with the active sites of cyclooxygenase-2 (COX-2). Triacetin, 3,6-dimethyl-3-Octanol, and 2R-Acetoxymethyl-1,3,3-trimethtyl-4t-(3-methyl-2-buten-1-yl)-1c-cyclohexanol docked comfortably with COX-2 with good scoring function (-CDocker energy) indicating their inhibitory potency against COX-2. 3,6-dimethyl-3-Octanol, displayed the lowest predicted free energy of binding (-21.4kcalmol(-1)) suggesting its stronger interaction with COX-2, this was followed by 2R - Acetoxymethyl-1, 3, 3-trimethtyl-4t-(3-methyl-2-buten-1-yl)-1c-cyclhexanol (BE=-20.5kcalmol(-1)), and triacetin (BE=-10.9kcalmol(-1)). Stigmastan - 3,5-diene failed to dock with COX-2. The observed suppressive effect of the DCM fraction of C. volubile flower methanolic extract on phagocytic oxidative burst indicates an immunomodulatory potential. This is further reflected in its free scavenging activities and synergetic modulation of COX-2 activities by its identified compounds in silico.

  1. Association between heat stress and oxidative stress in poultry; mitochondrial dysfunction and dietary interventions with phytochemicals.

    PubMed

    Akbarian, Abdollah; Michiels, Joris; Degroote, Jeroen; Majdeddin, Maryam; Golian, Abolghasem; De Smet, Stefaan

    2016-01-01

    Heat as a stressor of poultry has been studied extensively for many decades; it affects poultry production on a worldwide basis and has significant impact on well-being and production. More recently, the involvement of heat stress in inducing oxidative stress has received much interest. Oxidative stress is defined as the presence of reactive species in excess of the available antioxidant capacity of animal cells. Reactive species can modify several biologically cellular macromolecules and can interfere with cell signaling pathways. Furthermore, during the last decade, there has been an ever-increasing interest in the use of a wide array of natural feed-delivered phytochemicals that have potential antioxidant properties for poultry. In light of this, the current review aims to (1) summarize the mechanisms through which heat stress triggers excessive superoxide radical production in the mitochondrion and progresses into oxidative stress, (2) illustrate that this pathophysiology is dependent on the intensity and duration of heat stress, (3) present different nutritional strategies for mitigation of mitochondrial dysfunction, with particular focus on antioxidant phytochemicals. Oxidative stress that occurs with heat exposure can be manifest in all parts of the body; however, mitochondrial dysfunction underlies oxidative stress. In the initial phase of acute heat stress, mitochondrial substrate oxidation and electron transport chain activity are increased resulting in excessive superoxide production. During the later stage of acute heat stress, down-regulation of avian uncoupling protein worsens the oxidative stress situation causing mitochondrial dysfunction and tissue damage. Typically, antioxidant enzyme activities are upregulated. Chronic heat stress, however, leads to downsizing of mitochondrial metabolic oxidative capacity, up-regulation of avian uncoupling protein, a clear alteration in the pattern of antioxidant enzyme activities, and depletion of antioxidant

  2. Introduction to Oxidative Stress in Biomedical and Biological Research

    PubMed Central

    Breitenbach, Michael; Eckl, Peter

    2015-01-01

    Oxidative stress is now a well-researched area with thousands of new articles appearing every year. We want to give the reader here an overview of the topics in biomedical and basic oxidative stress research which are covered by the authors of this thematic issue. We also want to give the newcomer a short introduction into some of the basic concepts, definitions and analytical procedures used in this field. PMID:26117854

  3. Oxidative Stress: A Master Regulator of Plant Trade-Offs?

    PubMed

    Morales, Melanie; Munné-Bosch, Sergi

    2016-12-01

    Trade-offs between growth, reproduction, and defence have been documented. Oxidative stress is one of the physiological mechanisms that underlie trade-offs at the cellular and organ levels. The diversity of plant life forms and the complexity of scaling up limit our knowledge of oxidative stress as a universal mediator of life-history trade-offs at the organism level. Joint efforts by plant physiologists and ecologists will undoubtedly provide novel insights into this topic in the near future.

  4. Emerging importance of oxidative stress in regulating striated muscle elasticity.

    PubMed

    Beckendorf, Lisa; Linke, Wolfgang A

    2015-02-01

    The contractile function of striated muscle cells is altered by oxidative/nitrosative stress, which can be observed under physiological conditions but also in diseases like heart failure or muscular dystrophy. Oxidative stress causes oxidative modifications of myofilament proteins and can impair myocyte contractility. Recent evidence also suggests an important effect of oxidative stress on muscle elasticity and passive stiffness via modifications of the giant protein titin. In this review we provide a short overview of known oxidative modifications in thin and thick filament proteins and then discuss in more detail those oxidative stress-related modifications altering titin stiffness directly or indirectly. Direct modifications of titin include reversible disulfide bonding within the cardiac-specific N2-Bus domain, which increases titin stiffness, and reversible S-glutathionylation of cryptic cysteines in immunoglobulin-like domains, which only takes place after the domains have unfolded and which reduces titin stiffness in cardiac and skeletal muscle. Indirect effects of oxidative stress on titin can occur via reversible modifications of protein kinase signalling pathways (especially the NO-cGMP-PKG axis), which alter the phosphorylation level of certain disordered titin domains and thereby modulate titin stiffness. Oxidative stress also activates proteases such as matrix-metalloproteinase-2 and (indirectly via increasing the intracellular calcium level) calpain-1, both of which cleave titin to irreversibly reduce titin-based stiffness. Although some of these mechanisms require confirmation in the in vivo setting, there is evidence that oxidative stress-related modifications of titin are relevant in the context of biomarker design and represent potential targets for therapeutic intervention in some forms of muscle and heart disease.

  5. Mitochondrial oxidant stress in locus coeruleus is regulated by activity and nitric oxide synthase

    PubMed Central

    Sanchez–Padilla, J.; Guzman, J.N.; Ilijic, E.; Kondapalli, J.; Galtieri, D.J.; Yang, B.; Schieber, S.; Oertel, W.; Wokosin, D.; Schumacker, P. T.; Surmeier, D. J.

    2014-01-01

    Summary Loss of noradrenergic locus coeruleus (LC) neurons is a prominent feature of aging–related neurodegenerative diseases, like Parkinson’s disease (PD). The basis of this vulnerability is not understood. To explore possible physiological determinants, LC neurons were studied using electrophysiological and optical approaches in ex vivo mouse brain slices. These studies revealed that autonomous activity in LC neurons was accompanied by oscillations in dendritic Ca2+ concentration attributable to opening of L–type Ca2+ channels. This oscillation elevated mitochondrial oxidant stress and was attenuated by inhibition of nitric oxide synthase. The relationship between activity and stress was malleable, as arousal and carbon dioxide, each increased the spike rate, but differentially affected mitochondrial oxidant stress. Oxidant stress also was increased in an animal model of PD. Thus, our results point to activity–dependent Ca2+ entry and a resulting mitochondrial oxidant stress as factors contributing to the vulnerability of LC neurons. PMID:24816140

  6. COPD exacerbations . 2: aetiology.

    PubMed

    Sapey, E; Stockley, R A

    2006-03-01

    Exacerbations of COPD are thought to be caused by complex interactions between the host, bacteria, viruses, and environmental pollution. These factors increase the inflammatory burden in the lower airways, overwhelming the protective anti-inflammatory defences leading to tissue damage. Frequent exacerbations are associated with increased morbidity and mortality, a faster decline in lung function, and poorer health status, so prevention or optimal treatment of exacerbations is a global priority. In order to evolve new treatment strategies there has been great interest in the aetiology and pathophysiology of exacerbations, but progress has been hindered by the heterogeneous nature of these episodes, vague definitions of an exacerbation, and poor stratification of known confounding factors when interpreting results. We review how an exacerbation should be defined, its inflammatory basis, and the importance of exacerbations on disease progression. Important aetiologies, with their potential underlying mechanisms, are discussed and the significance of each aetiology is considered.

  7. Prohibitin as an oxidative stress biomarker in the eye.

    PubMed

    Lee, Hyunju; Arnouk, Hilal; Sripathi, Srinivas; Chen, Ping; Zhang, Ruonan; Bartoli, Manuela; Hunt, Richard C; Hrushesky, William J M; Chung, Hyewon; Lee, Sung Haeng; Jahng, Wan Jin

    2010-12-01

    Identification of biomarker proteins in the retina and 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 the retina and RPE was studied using 2D electrophoresis, immunohistochemistry, western blot, and mass spectrometry analysis. Comparison of expression levels with apoptotic markers as well as translocation between mitochondria and the nucleus imply that the regulation of prohibitin is an early signaling event in the RPE and retina under oxidative stress. Immunohistochemical analysis of murine aged and diabetic eyes further suggests that the regulation of prohibitin in the RPE/retina is related to aging- and diabetes-induced oxidative stress. Our proteomic approach implies that prohibitin in the RPE and the retina could be a new biomarker protein of oxidative stress in aging and diabetes.

  8. Nitrative and Oxidative Stress in Toxicology and Disease

    PubMed Central

    Roberts, Ruth A.; Laskin, Debra L.; Smith, Charles V.; Robertson, Fredika M.; Allen, Erin M. G.; Doorn, Jonathan A.; Slikker, William

    2009-01-01

    Persistent inflammation and the generation of reactive oxygen and nitrogen species play pivotal roles in tissue injury during disease pathogenesis and as a reaction to toxicant exposures. The associated oxidative and nitrative stress promote diverse pathologic reactions including neurodegenerative disorders, atherosclerosis, chronic inflammation, cancer, and premature labor and stillbirth. These effects occur via sustained inflammation, cellular proliferation and cytotoxicity and via induction of a proangiogenic environment. For example, exposure to the ubiquitous air pollutant ozone leads to generation of reactive oxygen and nitrogen species in lung macrophages that play a key role in subsequent tissue damage. Similarly, studies indicate that genes involved in regulating oxidative stress are altered by anesthetic treatment resulting in brain injury, most notable during development. In addition to a role in tissue injury in the brain, inflammation, and oxidative stress are implicated in Parkinson's disease, a neurodegenerative disease characterized by the loss of dopamine neurons. Recent data suggest a mechanistic link between oxidative stress and elevated levels of 3,4-dihydroxyphenylacetaldehyde, a neurotoxin endogenous to dopamine neurons. These findings have significant implications for development of therapeutics and identification of novel biomarkers for Parkinson's disease pathogenesis. Oxidative and nitrative stress is also thought to play a role in creating the proinflammatory microenvironment associated with the aggressive phenotype of inflammatory breast cancer. An understanding of fundamental concepts of oxidative and nitrative stress can underpin a rational plan of treatment for diseases and toxicities associated with excessive production of reactive oxygen and nitrogen species. PMID:19656995

  9. The effects of dietary restriction on oxidative stress in rodents

    PubMed Central

    Walsh, Michael E.; Shi, Yun; Van Remmen, Holly

    2013-01-01

    Oxidative stress is observed during aging and in numerous age-related diseases. Dietary restriction (DR) is a regimen that protects against disease and extends lifespan in multiple species. However, it is unknown how DR mediates its protective effects. One prominent and consistent effect of DR in a number of systems is the ability to reduce oxidative stress and damage. The purpose of this review is to comprehensively examine the hypothesis that dietary restriction reduces oxidative stress in rodents by decreasing reactive oxygen species (ROS) production and increasing antioxidant enzyme activity, leading to an overall reduction of oxidative damage to macromolecules. The literature reveals that the effects of DR on oxidative stress are complex and likely influenced by a variety of factors, including sex, species, tissue examined, types of ROS and antioxidant enzymes examined, and duration of DR. Here we present a comprehensive review of the existing literature on the effect of DR on mitochondrial ROS generation, antioxidant enzymes and oxidative damage. In a majority of studies, dietary restriction had little effect on mitochondrial ROS production or antioxidant activity. On the other hand, DR decreased oxidative damage in the majority of cases. Although the effects of DR on endogenous antioxidants are mixed, we find that glutathione levels are the most likely antioxidant to be increased by dietary restriction, which supports the emerging redox-stress hypothesis of aging. PMID:23743291

  10. Bridges between mitochondrial oxidative stress, ER stress and mTOR signaling in pancreatic β cells.

    PubMed

    Wang, Jing; Yang, Xin; Zhang, Jingjing

    2016-08-01

    Pancreatic β cell dysfunction, i.e., failure to provide insulin in concentrations sufficient to control blood sugar, is central to the etiology of all types of diabetes. Current evidence implicates mitochondrial oxidative stress and endoplasmic reticulum (ER) stress in pancreatic β cell loss and impaired insulin secretion. Oxidative and ER stress are interconnected so that misfolded proteins induce reactive oxygen species (ROS) production; likewise, oxidative stress disturbs the ER redox state thereby disrupting correct disulfide bond formation and proper protein folding. mTOR signaling regulates many metabolic processes including protein synthesis, cell growth, survival and proliferation. Oxidative stress inhibits mTORC1, which is considered an important suppressor of mitochondrial oxidative stress in β cells, and ultimately, controls cell survival. The interplay between ER stress and mTORC1 is complicated, since the unfolded protein response (UPR) activation can occur upstream or downstream of mTORC1. Persistent activation of mTORC1 initiates protein synthesis and UPR activation, while in the later phase induces ER stress. Chronic activation of ER stress inhibits Akt/mTORC1 pathway, while under particular settings, acute activation of UPR activates Akt-mTOR signaling. Thus, modulating mitochondrial oxidative stress and ER stress via mTOR signaling may be an approach that will effectively suppress obesity- or glucolipotoxicity-induced metabolic disorders such as insulin resistance and type 2 diabetes mellitus (T2DM). In this review, we focus on the regulations between mTOR signaling and mitochondrial oxidative or ER stress in pancreatic β cells.

  11. Infrared Dielectric Properties of Low-Stress Silicon Oxide

    NASA Technical Reports Server (NTRS)

    Cataldo, Giuseppe; Wollack, Edward J.; Brown, Ari D.; Miller, Kevin H.

    2016-01-01

    Silicon oxide thin films play an important role in the realization of optical coatings and high-performance electrical circuits. Estimates of the dielectric function in the far- and mid-infrared regime are derived from the observed transmittance spectrum for a commonly employed low-stress silicon oxide formulation. The experimental, modeling, and numerical methods used to extract the dielectric function are presented.

  12. CONCENTRATED AMBIENT AIR POLLUTION CREATES OXIDATIVE STRESS IN CNS MICROGLIA.

    EPA Science Inventory

    Nanometer size particles carry free radical activity on their surface and can produce oxidative stress (OS)-mediated damage upon impact to target cells. The initiating event of phage cell activation (i.e., the oxidative burst) is unknown, although many proximal events have been i...

  13. ELECTROSTATIC CHARGE STIMULATES OXIDATIVE STRESS IN CNS MICROGLIA.

    EPA Science Inventory

    Nanometer size particles carry free radical activity on their surface and can create oxidative stress (OS)-mediated inflammatory changes upon impact. The oxidative burst signals the activation of phage-lineage cells such as peripheral macrophages, Kupffer cells and CNS microgl...

  14. Interaction between osmotic and oxidative stress in diabetic precataractous lens: studies with a sorbitol dehydrogenase inhibitor.

    PubMed

    Obrosova, I G; Fathallah, L; Lang, H J

    1999-12-15

    Both sorbitol accumulation-linked osmotic stress and "pseudohypoxia" [increase in NADH/NAD+, similar to that in hypoxic tissues, and attributed to increased sorbitol dehydrogenase (1-iditol:NAD+ 5-oxidoreductase; EC 1.1.1.14; SDH) activity] have been invoked among the mechanisms underlying oxidative injury in target tissues for diabetic complications. We used the specific SDH inhibitor SDI-157 [2-methyl-4(4-N,N-dimethylaminosulfonyl-1-piperazino)pyrimid ine] to evaluate the role of osmotic stress versus "pseudohypoxia" in oxidative stress occurring in diabetic precataractous lens. Control and diabetic rats were treated with or without SDI-157 (100 mg/kg/day for 3 weeks). Lens malondialdehyde (MDA) plus 4-hydroxyalkenals (4-HA), MDA, GSH, and ascorbate levels, as well as the GSSG/GSH ratios, were similar in SDI-treated and untreated control rats, thus indicating that SDI-157 was not a prooxidant. Intralenticular osmotic stress, manifested by sorbitol levels, was more severe in SDI-treated diabetic rats (38.2+/-6.8 vs 21.2+/-3.5 micromol/g in untreated diabetic and 0.758+/-0.222 micromol/g in control rats, P<0.01 for both), while the decrease in the free cytosolic NAD+/NADH ratio was partially prevented (120+/-16 vs 88+/-11 in untreated diabetic rats and 143+/-13 in controls, P<0.01 for both). GSH and ascorbate levels were decreased, while MDA plus 4-HA and MDA levels were increased in diabetic rats versus controls; both antioxidant depletion and lipid aldehyde accumulation were exacerbated by SDI treatment. Superoxide dismutase (superoxide:superoxide oxidoreductase; EC 1.15.1.1), GSSG reductase (NAD[P]H:oxidized-glutathione oxidoreductase; EC 1.6.4.2), GSH transferase (glutathione S-transferase; EC 2.5.1.18), GSH peroxidase (glutathione:hydrogen-peroxide oxidoreductase; EC 1.11.1.9), and cytoplasmic NADH oxidase activities were increased in diabetic rats versus controls, and all the enzymes but GSH peroxidase were up-regulated further by SDI. In conclusion, sorbitol

  15. Effects of N-acetylcysteine on asthma exacerbation.

    PubMed

    Aliyali, Masoud; Poorhasan Amiri, Ali; Sharifpoor, Ali; Zalli, Fatemeh

    2010-06-01

    Airway mucus hypersecretion and increased oxidative stress are clinical and pathophysiological features of asthma exacerbation. We studied effects of N-acetylcysteine (NAC) as a mucolytic and antioxidant agent in asthma exacerbation. In this randomized, single-blinded, placebo-controlled study 50 patients ( 17 male, 33 female, mean age 48.94+/-13.68) with asthma exacerbation were randomized to receive either oral 600 mg b.d. N-acetylcysteine or placebo in addition to standard treatment during 5 days hospitalization. Daily measurements of wheezing, dyspnea, cough, sputum, expectoration, night sleep scores and morning PEFR were performed. There was no significant difference in wheezing score between patients assigned NAC and those assigned placebo in day 5(0.84[SD 0.94] VS 0.87[SD 0.79]) and also in cough score (0.72[SD 0.84] VS 0.79[SD 0.97]), dyspnea score (0.84[SD 1.06] VS 0.91[SD 1.01]), sputum score(0.79[SD 0.83] VS 0.62[SD 0.71]), expectoration score(0.79[SD 0.97] VS 0.83[SD 1.09]), night sleep score(1[SD 1.17] VS 0.67[SD 0.98] and morning PEFR (256[SD 96.36] VS 282[SD 98.86]). We concluded that addition of N-acetylcysteine to usual asthma medication has no significant effect in treatment of asthma exacerbation.

  16. Exacerbations of COPD

    PubMed Central

    Pavord, Ian D; Jones, Paul W; Burgel, Pierre-Régis; Rabe, Klaus F

    2016-01-01

    Exacerbations of chronic obstructive pulmonary disease (COPD) are defined as sustained worsening of a patient’s condition beyond normal day-to-day variations that is acute in onset, and that may also require a change in medication and/or hospitalization. Exacerbations have a significant and prolonged impact on health status and outcomes, and negative effects on pulmonary function. A significant proportion of exacerbations are unreported and therefore left untreated, leading to a poorer prognosis than those treated. COPD exacerbations are heterogeneous, and various phenotypes have been proposed which differ in biologic basis, prognosis, and response to therapy. Identification of biomarkers could enable phenotype-driven approaches for the management and prevention of exacerbations. For example, several biomarkers of inflammation can help to identify exacerbations most likely to respond to oral corticosteroids and antibiotics, and patients with a frequent exacerbator phenotype, for whom preventative treatment is appropriate. Reducing the frequency of exacerbations would have a beneficial impact on patient outcomes and prognosis. Preventative strategies include modification of risk factors, treatment of comorbid conditions, the use of bronchodilator therapy with long-acting β2-agonists or long-acting muscarinic antagonists, and inhaled corticosteroids. A better understanding of the mechanisms underlying COPD exacerbations will help to optimize use of the currently available and new interventions for preventing and treating exacerbations. PMID:26937187

  17. Oxidative stress contributes to autophagy induction in response to endoplasmic reticulum stress in Chlamydomonas reinhardtii.

    PubMed

    Pérez-Martín, Marta; Pérez-Pérez, María Esther; Lemaire, Stéphane D; Crespo, José L

    2014-10-01

    The accumulation of unfolded/misfolded proteins in the endoplasmic reticulum (ER) results in the activation of stress responses, such as the unfolded protein response or the catabolic process of autophagy to ultimately recover cellular homeostasis. ER stress also promotes the production of reactive oxygen species, which play an important role in autophagy regulation. However, it remains unknown whether reactive oxygen species are involved in ER stress-induced autophagy. In this study, we provide evidence connecting redox imbalance caused by ER stress and autophagy activation in the model unicellular green alga Chlamydomonas reinhardtii. Treatment of C. reinhardtii cells with the ER stressors tunicamycin or dithiothreitol resulted in up-regulation of the expression of genes encoding ER resident endoplasmic reticulum oxidoreductin1 oxidoreductase and protein disulfide isomerases. ER stress also triggered autophagy in C. reinhardtii based on the protein abundance, lipidation, cellular distribution, and mRNA levels of the autophagy marker ATG8. Moreover, increases in the oxidation of the glutathione pool and the expression of oxidative stress-related genes were detected in tunicamycin-treated cells. Our results revealed that the antioxidant glutathione partially suppressed ER stress-induced autophagy and decreased the toxicity of tunicamycin, suggesting that oxidative stress participates in the control of autophagy in response to ER stress in C. reinhardtii In close agreement, we also found that autophagy activation by tunicamycin was more pronounced in the C. reinhardtii sor1 mutant, which shows increased expression of oxidative stress-related genes.

  18. Salivary markers of oxidative stress in oral diseases

    PubMed Central

    Tóthová, L'ubomíra; Kamodyová, Natália; Červenka, Tomáš; Celec, Peter

    2015-01-01

    Saliva is an interesting alternative diagnostic body fluid with several specific advantages over blood. These include non-invasive and easy collection and related possibility to do repeated sampling. One of the obstacles that hinders the wider use of saliva for diagnosis and monitoring of systemic diseases is its composition, which is affected by local oral status. However, this issue makes saliva very interesting for clinical biochemistry of oral diseases. Periodontitis, caries, oral precancerosis, and other local oral pathologies are associated with oxidative stress. Several markers of lipid peroxidation, protein oxidation and DNA damage induced by reactive oxygen species can be measured in saliva. Clinical studies have shown an association with oral pathologies at least for some of the established salivary markers of oxidative stress. This association is currently limited to the population level and none of the widely used markers can be applied for individual diagnostics. Oxidative stress seems to be of local oral origin, but it is currently unclear whether it is caused by an overproduction of reactive oxygen species due to inflammation or by the lack of antioxidants. Interventional studies, both, in experimental animals as well as humans indicate that antioxidant treatment could prevent or slow-down the progress of periodontitis. This makes the potential clinical use of salivary markers of oxidative stress even more attractive. This review summarizes basic information on the most commonly used salivary markers of oxidative damage, antioxidant status, and carbonyl stress and the studies analyzing these markers in patients with caries or periodontitis. PMID:26539412

  19. Oxidative stress and autophagy: Crucial modulators of kidney injury

    PubMed Central

    Sureshbabu, Angara; Ryter, Stefan W.; Choi, Mary E.

    2015-01-01

    Both acute kidney injury (AKI) and chronic kidney disease (CKD) that lead to diminished kidney function are interdependent risk factors for increased mortality. If untreated over time, end stage renal disease (ESRD) is an inevitable outcome. Acute and chronic kidney diseases occur partly due to imbalance between the molecular mechanisms that govern oxidative stress, inflammation, autophagy and cell death. Oxidative stress refers to the cumulative effects of highly reactive oxidizing molecules that cause cellular damage. Autophagy removes damaged organelles, protein aggregates and pathogens by recruiting these substrates into double membrane vesicles called autophagosomes which subsequently fuse with lysosomes. Mounting evidence suggests that both oxidative stress and autophagy are significantly involved in kidney health and disease. However, very little is known about the signaling processes that link them. This review is focused on understanding the role of oxidative stress and autophagy in kidney diseases. In this review, we also discuss the potential relationships between oxidative stress and autophagy that may enable the development of better therapeutic intervention to halt the progression of kidney disease and promote its repair and resolution. PMID:25613291

  20. [Oxidative stress and fertility: false evidence and bad recipes].

    PubMed

    Ménézo, Y; Entezami, F; Lichtblau, I; Cohen, M; Belloc, S; Brack, M

    2012-12-01

    Worldwide statistics agree that at least one out of six couples has fertility problems. If the male gamete is the origin of this problem, it is generally admitted that the oxidative stress is involved. Modern life has obviously increased fertility problems through pesticides, xenoestrogenes, endocrine disrupting chemicals involved in plastic technology such as polychlorinated bisphenyls, bisphenol A, phthalates and alkylphenols… and other cosmetic additives. An important part of these compounds increases oxidative stress, at least in part. Oxidative stress is more than probably at the origin or recurrent increasing pathologies such as endometriosis. If the oocyte is theoretically able to repair oxidative stress linked decays such as DNA fragmentation and oxidation of bases, its capacity is finite and decreasing with age. In order to decrease DNA repair charge, reducing or even avoiding the generation of DNA damages related to reactive oxygen species through consumption of antioxidants compounds is often tempting: however Reasons will be provided to break from current treatments given haphazardly in the population in the age of reproduction, as well as the potential risks of over-exposure. Furthermore recommended treatments, in relation with the new concepts in oxidative stress, will be specified.

  1. Choline Diet and Its Gut Microbe Derived Metabolite, Trimethylamine N-Oxide (TMAO), Exacerbate Pressure Overload-Induced Heart Failure

    PubMed Central

    Organ, Chelsea L.; Otsuka, Hiroyuki; Bhushan, Shashi; Wang, Zeneng; Bradley, Jessica; Trivedi, Rishi; Polhemus, David J.; Tang, W. H. Wilson; Wu, Yuping; Hazen, Stanley L.; Lefer, David J.

    2015-01-01

    Background Trimethylamine N-oxide (TMAO), a gut microbe dependent metabolite of dietary choline and other trimethylamine containing nutrients, is both elevated in the circulation of patients suffering from heart failure (HF) and heralds worse overall prognosis. In animal studies, dietary choline or TMAO significantly accelerate atherosclerotic lesion development in ApoE deficient mice, and reduction in TMAO levels inhibits atherosclerosis development in the LDL receptor knockout mouse. Methods and Results C57BL6/J mice were fed either a control diet, a diet containing choline (1.2%) or a diet containing TMAO (0.12%) starting 3 weeks prior to surgical TAC. Mice were studied for 12 weeks following TAC. Cardiac function and left ventricular structure were monitored at 3-week intervals using echocardiography. Twelve weeks post-TAC myocardial tissues were collected to evaluate cardiac and vascular fibrosis, and blood samples were evaluated for cardiac BNP, choline, and TMAO levels. Pulmonary edema, cardiac enlargement, and left ventricular ejection fraction (LVEF) were significantly (p < 0.05, each) worse in mice fed either TMAO or choline supplemented diets compared to the control diet. In addition, myocardial fibrosis was also significantly greater (p < 0.01, each) in the TMAO and choline groups relative to controls. Conclusions Heart failure severity is significantly enhanced in mice fed diets supplemented in either choline or the gut microbe-dependent metabolite TMAO. The present results suggest that further studies are warranted examining whether gut microbiota and the dietary choline -> TMAO pathway contribute to increased heart failure susceptibility. PMID:26699388

  2. Combined oral contraceptive and nitric oxide synthesis inhibition synergistically causes cardiac hypertrophy and exacerbates insulin resistance in female rats.

    PubMed

    Olatunji, Lawrence A; Olaniyi, Kehinde S; Usman, Taofeek O; Abolarinwa, Bilikis A; Achile, Caleb J; Kim, In-Kyeom

    2017-03-20

    Combined oral contraceptive (COC) use or inhibition of nitric oxide (NO) synthesis has been shown to cause hypertension and insulin resistance. However, the concomitant effects of COC and NO deficiency on the heart and glucose regulation are not well known. We therefore hypothesized that COC treatment during NO deficiency would lead to the development of cardiac hypertrophy that is associated with aggravated glucose deregulation, pro-inflammatory and pro-fibrotic biomarkers. Eight-week-old female Wistar rats were randomly allotted into control, NO deficient (N(G)-nitro-l-arginine methyl ester: L-NAME; 20.0mg/kg b.w.), COC-treated (1.0μg ethinylestradiol+5.0μg levonorgestrel, p.o) and L-NAME+COC-treated groups. The animals were treated daily for 6 weeks. Systolic blood pressure was estimated by tail-cuff plethysmography, insulin resistance (IR) and β-cell function were estimated by homeostatic model of assessment (HOMA-IR and HOMA-β). Pro-inflammatory (C-reactive protein; CRP and uric acid) and pro-fibrotic (plasminogen activator inhibitor-1; PAI-1) biomarkers were estimated in the plasma. Cardiac histological examination was also done. Results show that COC or L-NAME treatments led to increased blood pressure, HOMA-IR, impaired β-cell function, PAI-1, CRP and uric acid, without significant effect on cardiac mass. L-NAME+COC-treated group had significantly higher blood pressure, HOMA-IR, impaired β-cell function, PAI-1, CRP and cardiac mass than COC- or L-NAME-treated groups. Histological examination validated that COC use during NO deficiency causes cardiac hypertrophy. The present study demonstrates that COC treatment and NO deficiency synergistically causes cardiac hypertrophy that is associated with aggravated glucose deregulation, atherogenic dyslipidemia, pro-inflammatory and pro-fibrotic markers.

  3. Stressed Oxidation of C/SiC Composites

    NASA Technical Reports Server (NTRS)

    Halbig, Michael C.; Brewer, David N.; Eckel, Andrew J.; Cawley, James D.

    1997-01-01

    Constant load, stressed oxidation testing was performed on T-300 C/SiC composites with a SiC seal coat. Test conditions included temperatures ranging from 350 C to 1500 C at stresses of 69 MPa and 172 MPa (10 and 25 ksi). The coupon subjected to stressed oxidation at 550 C/69 MPa for 25 hours had a room temperature residual strength one-half that of the as-received coupons. The coupon tested at the higher stress and all coupons tested at higher temperatures failed in less than 25 hr. Microstructural analysis of the fracture surfaces, using SEM (scanning electron microscopy), revealed the formation of reduced cross-sectional fibers with pointed tips. Analysis of composite cross-sections show pathways for oxygen ingress. The discussion will focus on fiber/matrix interphase oxidation and debonding as well as the formation and implications of the fiber tip morphology.

  4. Oxidative stress and mitochondrial dysfunction-linked neurodegenerative disorders.

    PubMed

    Islam, Md Torequl

    2017-01-01

    Reactive species play an important role in physiological functions. Overproduction of reactive species, notably reactive oxygen (ROS) and nitrogen (RNS) species along with the failure of balance by the body's antioxidant enzyme systems results in destruction of cellular structures, lipids, proteins, and genetic materials such as DNA and RNA. Moreover, the effects of reactive species on mitochondria and their metabolic processes eventually cause a rise in ROS/RNS levels, leading to oxidation of mitochondrial proteins, lipids, and DNA. Oxidative stress has been considered to be linked to the etiology of many diseases, including neurodegenerative diseases (NDDs) such as Alzheimer diseases, Amyotrophic lateral sclerosis, Friedreich's ataxia, Huntington's disease, Multiple sclerosis, and Parkinson's diseases. In addition, oxidative stress causing protein misfold may turn to other NDDs include Creutzfeldt-Jakob disease, Bovine Spongiform Encephalopathy, Kuru, Gerstmann-Straussler-Scheinker syndrome, and Fatal Familial Insomnia. An overview of the oxidative stress and mitochondrial dysfunction-linked NDDs has been summarized in this review.

  5. Statins lower calcium-induced oxidative stress in isolated mitochondria.

    PubMed

    Parihar, A; Parihar, M S; Zenebe, W J; Ghafourifar, P

    2012-04-01

    Statins are widely used cholesterol-lowering agents that exert cholesterol-independent effects including antioxidative. The present study delineates the effects of statins, atorvastatin, and simvastatin on oxidative stress and functions of mitochondria that are the primary cellular sources of oxidative stress. In isolated rat liver mitochondria, both the statins prevented calcium-induced cytochrome c release, lipid peroxidation, and opening of the mitochondrial membrane permeability transition (MPT). Both the statins decreased the activity of mitochondrial nitric oxide synthase (mtNOS), lowered the intramitochondrial ionized calcium, and increased the mitochondrial transmembrane potential. Our findings suggest that statins lower intramitochondrial ionized calcium that decreases mtNOS activity, lowers oxidative stress, prevents MPT opening, and prevents the release of cytochrome c from the mitochondria. These results provide a novel framework for understanding the antioxidative properties of statins and their effects on mitochondrial functions.

  6. Markers of Oxidative Stress and Neuroprogression in Depression Disorder.

    PubMed

    Vaváková, Magdaléna; Ďuračková, Zdeňka; Trebatická, Jana

    2015-01-01

    Major depression is multifactorial disorder with high prevalence and alarming prognostic in the nearest 15 years. Several mechanisms of depression are known. Neurotransmitters imbalance and imbalance between neuroprogressive and neuroprotective factors are observed in major depression. Depression is accompanied by inflammatory responses of the organism and consequent elevation of proinflammatory cytokines and increased lipid peroxidation are described in literature. Neuropsychiatric disorders including major depression are also associated with telomerase shortening, oxidative changes in nucleotides, and polymorphisms in several genes connected to metabolism of reactive oxygen species. Mitochondrion dysfunction is directly associated with increasing levels of oxidative stress. Oxidative stress plays significant role in pathophysiology of major depression via actions of free radicals, nonradical molecules, and reactive oxygen and nitrogen species. Products of oxidative stress represent important parameters for measuring and predicting of depression status as well as for determining effectiveness of administrated antidepressants. Positive effect of micronutrients, vitamins, and antioxidants in depression treatment is also reviewed.

  7. Morphine as a Potential Oxidative Stress-Causing Agent.

    PubMed

    Skrabalova, Jitka; Drastichova, Zdenka; Novotny, Jiri

    2013-11-01

    Morphine exhibits important pharmacological effects for which it has been used in medical practice for quite a long time. However, it has a high addictive potential and can be abused. Long-term use of this drug can be connected with some pathological consequences including neurotoxicity and neuronal dysfunction, hepatotoxicity, kidney dysfunction, oxidative stress and apoptosis. Therefore, most studies examining the impact of morphine have been aimed at determining the effects induced by chronic morphine exposure in the brain, liver, cardiovascular system and macrophages. It appears that different tissues may respond to morphine diversely and are distinctly susceptible to oxidative stress and subsequent oxidative damage of biomolecules. Importantly, production of reactive oxygen/nitrogen species induced by morphine, which have been observed under different experimental conditions, can contribute to some pathological processes, degenerative diseases and organ dysfunctions occurring in morphine abusers or morphine-treated patients. This review attempts to provide insights into the possible relationship between morphine actions and oxidative stress.

  8. Oxidative stress, insulin resistance, dyslipidemia and type 2 diabetes mellitus

    PubMed Central

    Tangvarasittichai, Surapon

    2015-01-01

    Oxidative stress is increased in metabolic syndrome and type 2 diabetes mellitus (T2DM) and this appears to underlie the development of cardiovascular disease, T2DM and diabetic complications. Increased oxidative stress appears to be a deleterious factor leading to insulin resistance, dyslipidemia, β-cell dysfunction, impaired glucose tolerance and ultimately leading to T2DM. Chronic oxidative stress, hyperglycemia and dyslipidemia are particularly dangerous for β-cells from lowest levels of antioxidant, have high oxidative energy requirements, decrease the gene expression of key β-cell genes and induce cell death. If β-cell functioning is impaired, it results in an under production of insulin, impairs glucose stimulated insulin secretion, fasting hyperglycemia and eventually the development of T2DM. PMID:25897356

  9. Markers of Oxidative Stress and Neuroprogression in Depression Disorder

    PubMed Central

    Vaváková, Magdaléna; Trebatická, Jana

    2015-01-01

    Major depression is multifactorial disorder with high prevalence and alarming prognostic in the nearest 15 years. Several mechanisms of depression are known. Neurotransmitters imbalance and imbalance between neuroprogressive and neuroprotective factors are observed in major depression. Depression is accompanied by inflammatory responses of the organism and consequent elevation of proinflammatory cytokines and increased lipid peroxidation are described in literature. Neuropsychiatric disorders including major depression are also associated with telomerase shortening, oxidative changes in nucleotides, and polymorphisms in several genes connected to metabolism of reactive oxygen species. Mitochondrion dysfunction is directly associated with increasing levels of oxidative stress. Oxidative stress plays significant role in pathophysiology of major depression via actions of free radicals, nonradical molecules, and reactive oxygen and nitrogen species. Products of oxidative stress represent important parameters for measuring and predicting of depression status as well as for determining effectiveness of administrated antidepressants. Positive effect of micronutrients, vitamins, and antioxidants in depression treatment is also reviewed. PMID:26078821

  10. OXIDATIVE STRESS 3 Is a Chromatin-Associated Factor Involved in Tolerance to Heavy Metals and Oxidative Stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A cDNA expression library from Brassica juncea was introduced into the fission yeast Schizosaccharomyces pombe to select for transformants tolerant to cadmium. Transformants expressing OXIDATIVE STRESS 3 (OXS3) or OXS3-Like cDNA exhibited enhanced tolerance to a range of metals and oxidizing chemica...

  11. Carbon monoxide pollution aggravates ischemic heart failure through oxidative stress pathway.

    PubMed

    Reboul, Cyril; Boissière, Julien; André, Lucas; Meyer, Gregory; Bideaux, Patrice; Fouret, Gilles; Feillet-Coudray, Christine; Obert, Philippe; Lacampagne, Alain; Thireau, Jérôme; Cazorla, Olivier; Richard, Sylvain

    2017-01-03

    Risk of hospital readmission and cardiac mortality increases with atmospheric pollution for patients with heart failure. The underlying mechanisms are unclear. Carbon monoxide (CO) a ubiquitous environmental pollutant could be involved. We explored the effect of daily exposure of CO relevant to urban pollution on post-myocardial infarcted animals. Rats with ischemic heart failure were exposed 4 weeks to daily peaks of CO mimicking urban exposure or to standard filtered air. CO exposure worsened cardiac contractile dysfunction evaluated by echocardiography and at the cardiomyocyte level. In line with clinical reports, the animals exposed to CO also exhibited a severe arrhythmogenic phenotype with numerous sustained ventricular tachycardias as monitored by surface telemetric electrocardiograms. CO did not affect cardiac β-adrenergic responsiveness. Instead, mitochondrial dysfunction was exacerbated leading to additional oxidative stress and Ca(2+) cycling alterations. This was reversed following acute antioxidant treatment of cardiomyocytes with N-acetylcysteine confirming involvement of CO-induced oxidative stress. Exposure to daily peaks of CO pollution aggravated cardiac dysfunction in rats with ischemic heart failure by specifically targeting mitochondria and generating ROS-dependent alterations. This pathway may contribute to the high sensibility and vulnerability of individuals with cardiac disease to environmental outdoor air quality.

  12. Carbon monoxide pollution aggravates ischemic heart failure through oxidative stress pathway

    PubMed Central

    Reboul, Cyril; Boissière, Julien; André, Lucas; Meyer, Gregory; Bideaux, Patrice; Fouret, Gilles; Feillet-Coudray, Christine; Obert, Philippe; Lacampagne, Alain; Thireau, Jérôme; Cazorla, Olivier; Richard, Sylvain

    2017-01-01

    Risk of hospital readmission and cardiac mortality increases with atmospheric pollution for patients with heart failure. The underlying mechanisms are unclear. Carbon monoxide (CO) a ubiquitous environmental pollutant could be involved. We explored the effect of daily exposure of CO relevant to urban pollution on post-myocardial infarcted animals. Rats with ischemic heart failure were exposed 4 weeks to daily peaks of CO mimicking urban exposure or to standard filtered air. CO exposure worsened cardiac contractile dysfunction evaluated by echocardiography and at the cardiomyocyte level. In line with clinical reports, the animals exposed to CO also exhibited a severe arrhythmogenic phenotype with numerous sustained ventricular tachycardias as monitored by surface telemetric electrocardiograms. CO did not affect cardiac β–adrenergic responsiveness. Instead, mitochondrial dysfunction was exacerbated leading to additional oxidative stress and Ca2+ cycling alterations. This was reversed following acute antioxidant treatment of cardiomyocytes with N-acetylcysteine confirming involvement of CO-induced oxidative stress. Exposure to daily peaks of CO pollution aggravated cardiac dysfunction in rats with ischemic heart failure by specifically targeting mitochondria and generating ROS-dependent alterations. This pathway may contribute to the high sensibility and vulnerability of individuals with cardiac disease to environmental outdoor air quality. PMID:28045070

  13. Perinatal Oxidative Stress May Affect Fetal Ghrelin Levels in Humans.

    PubMed

    Luo, Zhong-Cheng; Bilodeau, Jean-François; Nuyt, Anne Monique; Fraser, William D; Julien, Pierre; Audibert, Francois; Xiao, Lin; Garofalo, Carole; Levy, Emile

    2015-12-08

    In vitro cell model studies have shown that oxidative stress may affect beta-cell function. It is unknown whether oxidative stress may affect metabolic health in human fetuses/newborns. In a singleton pregnancy cohort (n = 248), we studied maternal (24-28 weeks gestation) and cord plasma biomarkers of oxidative stress [malondialdehyde (MDA), F2-isoprostanes] in relation to fetal metabolic health biomarkers including cord plasma glucose-to-insulin ratio (an indicator of insulin sensitivity), proinsulin-to-insulin ratio (an indicator of beta-cell function), insulin, IGF-I, IGF-II, leptin, adiponectin and ghrelin concentrations. Strong positive correlations were observed between maternal and cord plasma biomarkers of oxidative stress (r = 0.33 for MDA, r = 0.74 for total F2-isoprostanes, all p < 0.0001). Adjusting for gestational age at blood sampling, cord plasma ghrelin concentrations were consistently negatively correlated to oxidative stress biomarkers in maternal (r = -0.32, p < 0.0001 for MDA; r = -0.31, p < 0.0001 for F2-isoprostanes) or cord plasma (r = -0.13, p = 0.04 for MDA; r = -0.32, p < 0.0001 for F2-isoprostanes). Other fetal metabolic health biomarkers were not correlated to oxidative stress. Adjusting for maternal and pregnancy characteristics, similar associations were observed. Our study provides the first preliminary evidence suggesting that oxidative stress may affect fetal ghrelin levels in humans. The implications in developmental "programming" the vulnerability to metabolic syndrome related disorders remain to be elucidated.

  14. Contaminant-induced oxidative stress in fish: a mechanistic approach.

    PubMed

    Lushchak, Volodymyr I

    2016-04-01

    The presence of reactive oxygen species (ROS) in living organisms was described more than 60 years ago and virtually immediately it was suggested that ROS were involved in various pathological processes and aging. The state when ROS generation exceeds elimination leading to an increased steady-state ROS level has been called "oxidative stress." Although ROS association with many pathological states in animals is well established, the question of ROS responsibility for the development of these states is still open. Fish represent the largest group of vertebrates and they inhabit a broad range of ecosystems where they are subjected to many different aquatic contaminants. In many cases, the deleterious effects of contaminants have been connected to induction of oxidative stress. Therefore, deciphering of molecular mechanisms leading to such contaminant effects and organisms' response may let prevent or minimize deleterious impacts of oxidative stress. This review describes general aspects of ROS homeostasis, in particular highlighting its basic aspects, modification of cellular constituents, operation of defense systems and ROS-based signaling with an emphasis on fish systems. A brief introduction to oxidative stress theory is accompanied by the description of a recently developed classification system for oxidative stress based on its intensity and time course. Specific information on contaminant-induced oxidative stress in fish is covered in sections devoted to such pollutants as metal ions (particularly iron, copper, chromium, mercury, arsenic, nickel, etc.), pesticides (insecticides, herbicides, and fungicides) and oil with accompanying pollutants. In the last section, certain problems and perspectives in studies of oxidative stress in fish are described.

  15. The effect of oxidative stress during exercise in the horse.

    PubMed

    Williams, C A

    2016-10-01

    Oxidative stress is an imbalance of the oxidant-to-antioxidant ratio in the body. Increases in oxidative stress and changes in antioxidant status have been shown during endurance and intense exercise and eventing competition in horses. Antioxidants include vitamins, minerals, enzymes, and proteins that must be synthesized in the body or obtained from the diet. Therefore, exercise level and diet are both factors that play a role in influencing the oxidative stress and antioxidant status of the equine athlete. Along with exercise intensity and duration, diet, age, and training program can also affect oxidative stress in the horse. Several studies using exogenous supplementation of vitamin E, vitamin C, and alpha-lipoic acid have shown positive results in decreasing the effects of exercise (endurance and intense exercise)-induced oxidative stress and increasing the antioxidant status based on the markers and antioxidants measured, whereas other studies using superoxide dismutase showed little effects on the exercise horse. The "free radical theory of aging" states that long-term effects of the degenerative changes associated with aging may induce oxidative stress. However, in old horses (22 ± 2 yr), lipid peroxidation levels and blood antioxidant concentrations were similar to those found in younger but mature (12 ± 2 yr) horses both at rest and during exercise. Other studies found that yearlings (18 ± 2.4 mo) that are novel to forced exercise had less lipid peroxidation and greater antioxidant status than mature mares (13 ± 2.1 yr) prior to exercise training. Exercise training reduced oxidative stress markers and improved antioxidant status in mares, whereas few effects were seen in yearlings. This indicates that youth provided more defense against oxidative stress due to exercise than the exercise training program. Other studies during competition (endurance, jumping, eventing, and racing) have investigated the influence on oxidative stress with varying results

  16. Oxidative stress alters global histone modification and DNA methylation.

    PubMed

    Niu, Yingmei; DesMarais, Thomas L; Tong, Zhaohui; Yao, Yixin; Costa, Max

    2015-05-01

    The JmjC domain-containing histone demethylases can remove histone lysine methylation and thereby regulate gene expression. The JmjC domain uses iron Fe(II) and α-ketoglutarate (αKG) as cofactors in an oxidative demethylation reaction via hydroxymethyl lysine. We hypothesize that reactive oxygen species will oxidize Fe(II) to Fe(III), thereby attenuating the activity of JmjC domain-containing histone demethylases. To minimize secondary responses from cells, extremely short periods of oxidative stress (3h) were used to investigate this question. Cells that were exposed to hydrogen peroxide (H2O2) for 3h exhibited increases in several histone methylation marks including H3K4me3 and decreases of histone acetylation marks including H3K9ac and H4K8ac; preincubation with ascorbate attenuated these changes. The oxidative stress level was measured by generation of 2',7'-dichlorofluorescein, GSH/GSSG ratio, and protein carbonyl content. A cell-free system indicated that H2O2 inhibited histone demethylase activity where increased Fe(II) rescued this inhibition. TET protein showed a decreased activity under oxidative stress. Cells exposed to a low-dose and long-term (3 weeks) oxidative stress also showed increased global levels of H3K4me3 and H3K27me3. However, these global methylation changes did not persist after washout. The cells exposed to short-term oxidative stress also appeared to have higher activity of class I/II histone deacetylase (HDAC) but not class III HDAC. In conclusion, we have found that oxidative stress transiently alters the epigenetic program process through modulating the activity of enzymes responsible for demethylation and deacetylation of histones.

  17. Exercise-Induced Oxidative Stress Responses in the Pediatric Population

    PubMed Central

    Avloniti, Alexandra; Chatzinikolaou, Athanasios; Deli, Chariklia K.; Vlachopoulos, Dimitris; Gracia-Marco, Luis; Leontsini, Diamanda; Draganidis, Dimitrios; Jamurtas, Athanasios Z.; Mastorakos, George; Fatouros, Ioannis G.

    2017-01-01

    Adults demonstrate an upregulation of their pro- and anti-oxidant mechanisms in response to acute exercise while systematic exercise training enhances their antioxidant capacity, thereby leading to a reduced generation of free radicals both at rest and in response to exercise stress. However, less information exists regarding oxidative stress responses and the underlying mechanisms in the pediatric population. Evidence suggests that exercise-induced redox perturbations may be valuable in order to monitor exercise-induced inflammatory responses and as such training overload in children and adolescents as well as monitor optimal growth and development. The purpose of this review was to provide an update on oxidative stress responses to acute and chronic exercise in youth. It has been documented that acute exercise induces age-specific transient alterations in both oxidant and antioxidant markers in children and adolescents. However, these responses seem to be affected by factors such as training phase, training load, fitness level, mode of exercise etc. In relation to chronic adaptation, the role of training on oxidative stress adaptation has not been adequately investigated. The two studies performed so far indicate that children and adolescents exhibit positive adaptations of their antioxidant system, as adults do. More studies are needed in order to shed light on oxidative stress and antioxidant responses, following acute exercise and training adaptations in youth. Available evidence suggests that small amounts of oxidative stress may be necessary for growth whereas the transition to adolescence from childhood may promote maturation of pro- and anti-oxidant mechanisms. Available evidence also suggests that obesity may negatively affect basal and exercise-related antioxidant responses in the peripubertal period during pre- and early-puberty. PMID:28106721

  18. Exercise-Induced Oxidative Stress Responses in the Pediatric Population.

    PubMed

    Avloniti, Alexandra; Chatzinikolaou, Athanasios; Deli, Chariklia K; Vlachopoulos, Dimitris; Gracia-Marco, Luis; Leontsini, Diamanda; Draganidis, Dimitrios; Jamurtas, Athanasios Z; Mastorakos, George; Fatouros, Ioannis G

    2017-01-17

    Adults demonstrate an upregulation of their pro- and anti-oxidant mechanisms in response to acute exercise while systematic exercise training enhances their antioxidant capacity, thereby leading to a reduced generation of free radicals both at rest and in response to exercise stress. However, less information exists regarding oxidative stress responses and the underlying mechanisms in the pediatric population. Evidence suggests that exercise-induced redox perturbations may be valuable in order to monitor exercise-induced inflammatory responses and as such training overload in children and adolescents as well as monitor optimal growth and development. The purpose of this review was to provide an update on oxidative stress responses to acute and chronic exercise in youth. It has been documented that acute exercise induces age-specific transient alterations in both oxidant and antioxidant markers in children and adolescents. However, these responses seem to be affected by factors such as training phase, training load, fitness level, mode of exercise etc. In relation to chronic adaptation, the role of training on oxidative stress adaptation has not been adequately investigated. The two studies performed so far indicate that children and adolescents exhibit positive adaptations of their antioxidant system, as adults do. More studies are needed in order to shed light on oxidative stress and antioxidant responses, following acute exercise and training adaptations in youth. Available evidence suggests that small amounts of oxidative stress may be necessary for growth whereas the transition to adolescence from childhood may promote maturation of pro- and anti-oxidant mechanisms. Available evidence also suggests that obesity may negatively affect basal and exercise-related antioxidant responses in the peripubertal period during pre- and early-puberty.

  19. Oxidative stress in glaucomatous neurodegeneration: mechanisms and consequences.

    PubMed

    Tezel, Gülgün

    2006-09-01

    Reactive oxygen species (ROS) are generated as by-products of cellular metabolism, primarily in the mitochondria. Although ROS are essential participants in cell signaling and regulation, when their cellular production overwhelms the intrinsic antioxidant capacity, damage to cellular macromolecules such as DNA, proteins, and lipids ensues. Such a state of "oxidative stress" is thought to contribute to the pathogenesis of a number of neurodegenerative diseases. Growing evidence supports the involvement of oxidative stress as a common component of glaucomatous neurodegeneration in different subcellular compartments of retinal ganglion cells (RGCs). Besides the evidence of direct cytotoxic consequences leading to RGC death, it also seems highly possible that ROS are involved in signaling RGC death by acting as a second messenger and/or modulating protein function by redox modifications of downstream effectors through enzymatic oxidation of specific amino acid residues. Different studies provide cumulating evidence, which supports the association of ROS with different aspects of the neurodegenerative process. Oxidative protein modifications during glaucomatous neurodegeneration increase neuronal susceptibility to damage and also lead to glial dysfunction. Oxidative stress-induced dysfunction of glial cells may contribute to spreading neuronal damage by secondary degeneration. Oxidative stress also promotes the accumulation of advanced glycation end products in glaucomatous tissues. In addition, oxidative stress takes part in the activation of immune response during glaucomatous neurodegeneration, as ROS stimulate the antigen presenting ability of glial cells and also function as co-stimulatory molecules during antigen presentation. By discussing current evidence, this review provides a broad perspective on cellular mechanisms and potential consequences of oxidative stress in glaucoma.

  20. Oxidative stress in patients with obstructive sleep apnoea syndrome.

    PubMed

    Passali, D; Corallo, G; Yaremchuk, S; Longini, M; Proietti, F; Passali, G C; Bellussi, L

    2015-12-01

    Obstructive sleep apnoea syndrome (OSAS) is a disorder that leads to metabolic abnormalities and increased cardiovascular risk. The aim of this study was to identify early laboratory markers of cardiovascular disease through analysis of oxidative stress in normal subjects and patients with OSAS. A prospective study was designed to compare outcomes of oxidative stress laboratory tests in 20 adult patients with OSAS and a control group of 20 normal subjects. Laboratory techniques for detecting and quantifying free radical damage must be targeted to assess the pro-oxidant component and the antioxidant in order to obtain an overall picture of oxidative balance. No statistical differences in age, sex distribution, or BMI were found between the two groups (p>0.05). There were significant differences in the apnoea/hypopnoea index (AHI) between OSAS patients and the control group (p<0.05). Statistically significant differences in isoprostane, advanced oxidation protein products (AOPP) and non-protein bound iron (NPBI) levels were found between the study and control groups. No significant difference in the levels of thiol biomarkers was found between the two groups. The main finding of the present study was increased production of oxidative stress biomarkers in OSAS patients. The major difference between thiols and other oxidative stress biomarkers is that thiols are antioxidants, while the others are expressions of oxidative damage. The findings of the present study indicate that biomarkers of oxidative stress in OSAS may be used as a marker of upper airway obstructive episodes due to mechanical trauma, as well as a marker of hypoxaemia causing local oropharyngeal inflammation.

  1. Role of Nrf2 in Oxidative Stress and Toxicity

    PubMed Central

    Ma, Qiang

    2015-01-01

    Organismal life encounters reactive oxidants from internal metabolism and environmental toxicant exposure. Reactive oxygen and nitrogen species cause oxidative stress and are traditionally viewed as being harmful. On the other hand, controlled production of oxidants in normal cells serves useful purposes to regulate signaling pathways. Reactive oxidants are counterbalanced by complex antioxidant defense systems regulated by a web of pathways to ensure that the response to oxidants is adequate for the body’s needs. A recurrent theme in oxidant signaling and antioxidant defense is reactive cysteine thiol–based redox signaling. The nuclear factor erythroid 2–related factor 2 (Nrf2) is an emerging regulator of cellular resistance to oxidants. Nrf2 controls the basal and induced expression of an array of antioxidant response element–dependent genes to regulate the physiological and pathophysiological outcomes of oxidant exposure. This review discusses the impact of Nrf2 on oxidative stress and toxicity and how Nrf2 senses oxidants and regulates antioxidant defense. PMID:23294312

  2. Erdosteine for COPD exacerbations.

    PubMed

    2008-10-01

    The mucolytic drug erdosteine (Erdotin - Galen) is licensed in the UK as treatment for up to 10 days "for the symptomatic treatment of acute exacerbations of chronic bronchitis in adults". This indication differs from that for carbocisteine and mecysteine, two older mucolytic drugs that are licensed for adjunctive treatment in respiratory disorders characterised by viscous mucus, and typically used for longer to prevent exacerbations of chronic obstructive pulmonary disease (COPD). Does erdosteine have a role for people with COPD exacerbations?

  3. Hepatic oxidative stress promotes insulin-STAT-5 signaling and obesity by inactivating protein tyrosine phosphatase N2

    PubMed Central

    Gurzov, Esteban N.; Tran, Melanie; Fernandez-Rojo, Manuel A; Merry, Troy L; Zhang, Xinmei; Xu, Yang; Fukushima, Atsushi; Waters, Michael J; Watt, Matthew J; Andrikopoulos, Sofianos; Neel, Benjamin G; Tiganis, Tony

    2015-01-01

    Hepatic insulin resistance is a key contributor to the pathogenesis of obesity and type 2 diabetes (T2D). Paradoxically the development of insulin resistance in the liver is not universal, but pathway-selective, such that insulin fails to suppress gluconeogenesis but promotes lipogenesis, contributing to the hyperglycemia, steatosis and hypertriglyceridemia that underpin the deteriorating glucose control and microvascular complications in T2D. The molecular basis for the pathway-specific insulin resistance remains unknown. Here we report that oxidative stress accompanying obesity inactivates protein-tyrosine phosphatases (PTPs) in the liver, which activates select signaling pathways that exacerbate disease progression. In obese mice, hepatic PTPN2 (TCPTP) inactivation promoted lipogenesis and steatosis and insulin-STAT-5 signaling. The enhanced STAT-5 signaling increased hepatic IGF-1 production, which suppressed central growth hormone release and exacerbated the development of obesity and T2D. Our studies define a mechanism for the development of selective insulin resistance with wide-ranging implications for diseases characterised by oxidative stress. PMID:24954415

  4. Targets of oxidative stress in cardiovascular system.

    PubMed

    Chakraborti, T; Ghosh, S K; Michael, J R; Batabyal, S K; Chakraborti, S

    1998-10-01

    Although oxidants such as superoxide (O2.) and hydrogen peroxide (H2O2) play a role in host-mediated destruction of foreign pathogens yet excessive generation of oxidants may lead to a variety of pathological complications in the cardiovascular system. An important mechanism by which oxidants cause dysfunction of the cardiovascular system appears to be due to the increase in intracellular free Ca2+ concentration. Oxidants cause cellular Ca2+ mobilization by modulating activities of a variety of regulators such as Na+/H+ and Na+/Ca2+ exchangers, Na+/K+ ATPase and Ca2+ ATPase and Ca2+ channels that are associated with Ca2+ transport in the plasma membrane and the sarco(endo)plasmic reticular membrane of myocardial cells. Recent research have suggested that the increase in Ca2+ level by oxidants plays a pivotal role in inducing several protein kinases such as protein kinase C, tyrosine kinase and mitogen activated protein kinases. Oxidant-mediated alteration of different signal transduction systems and their interations eventually regulate a variety of pathological conditions such as atherosclerosis, apoptosis and necrosis in the myocardium.

  5. Myelophil ameliorates brain oxidative stress in mice subjected to restraint stress.

    PubMed

    Lee, Jin-Seok; Kim, Hyung-Geug; Han, Jong-Min; Lee, Jong-Suk; Son, Seung-Wan; Ahn, Yo-Chan; Son, Chang-Gue

    2012-12-03

    We evaluated the pharmacological effects of Myelophil, a 30% ethanol extract of a mix of Astragali Radix and Salviae Radix, on oxidative stress-induced brain damage in mice caused by restraint stress. C57BL/6 male mice (eight weeks old) underwent daily oral administration of distilled water, Myelophil (25, 50, or 100mg/kg), or ascorbic acid (100mg/kg) 1h before induction of restraint stress, which involved 3h of immobilization per day for 21days. Nitric oxide levels, lipid peroxidation, activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione redox system enzymes), and concentrations of adrenaline, corticosterone, and interferon-γ, were measured in brain tissues and/or sera. Restraint stress-induced increases in nitric oxide levels (serum and brain tissues) and lipid peroxidation (brain tissues) were significantly attenuated by Myelophil treatment. Restraint stress moderately lowered total antioxidant capacity, catalase activity, glutathione content, and the activities of glutathione reductase, glutathione peroxidase, and glutathione S-transferase; all these responses were reversed by Myelophil. Myelophil significantly attenuated the elevated serum concentrations of adrenaline and corticosterone and restored serum and brain interferon-γ levels. Moreover, Myelophil normalized expression of the genes encoding monoamine oxidase A, catechol-O-methyltransferase, and phenylethanolamine N-methyltransferase, which was up-regulated by restraint stress in brain tissues. These results suggest that Myelophil has pharmacological properties protects brain tissues against stress-associated oxidative stress damage, perhaps in part through regulation of stress hormones.

  6. Acrylonitrile-Induced Oxidative Stress and Oxidative DNA Damage in Male Sprague-Dawley Rats

    PubMed Central

    Kamendulis, Lisa M.; Klaunig, James E.

    2009-01-01

    Studies have demonstrated that the induction of oxidative stress may be involved in brain tumor induction in rats by acrylonitrile. The present study examined whether acrylonitrile induces oxidative stress and DNA damage in rats and whether blood can serve as a valid surrogate for the biomonitoring of oxidative stress induced by acrylonitrile in the exposed population. Male Sprague-Dawley rats were treated with 0, 3, 30, 100, and 200 ppm acrylonitrile in drinking water for 28 days. One group of rats were also coadministered N-acetyl cysteine (NAC) (0.3% in diet) with acrylonitrile (200 ppm in drinking water) to examine whether antioxidant supplementation was protective against acrylonitrile-induced oxidative stress. Direct DNA strand breakage in white blood cells (WBC) and brain was measured using the alkaline comet assay. Oxidative DNA damage in WBC and brain was evaluated using formamidopyrimidine DNA glycosylase (fpg)-modified comet assay and with high-performance liquid chromatography-electrochemical detection. No significant increase in direct DNA strand breaks was observed in brain and WBC from acrylonitrile-treated rats. However, oxidative DNA damage (fpg comet and 8′hydroxyl-2-deoxyguanosine) in brain and WBC was increased in a dose-dependent manner. In addition, plasma levels of reactive oxygen species (ROS) increased in rats administered acrylonitrile. Dietary supplementation with NAC prevented acrylonitrile-induced oxidative DNA damage in brain and WBC. A slight, but significant, decrease in the GSH:GSSG ratio was seen in brain at acrylonitrile doses > 30 ppm. These results provide additional support that the mode of action for acrylonitrile-induced astrocytomas involves the induction of oxidative stress and damage. Significant associations were seen between oxidative DNA damage in WBC and brain, ROS formation in plasma, and the reported tumor incidences. Since oxidative DNA damage in brain correlated with oxidative damage in WBC, these results suggest

  7. Nitric oxide signaling in plant responses to abiotic stresses.

    PubMed

    Qiao, Weihua; Fan, Liu-Min

    2008-10-01

    Nitric oxide (NO) plays important roles in diverse physiological processes in plants. NO can provoke both beneficial and harmful effects, which depend on the concentration and location of NO in plant cells. This review is focused on NO synthesis and the functions of NO in plant responses to abiotic environmental stresses. Abiotic stresses mostly induce NO production in plants. NO alleviates the harmfulness of reactive oxygen species, and reacts with other target molecules, and regulates the expression of stress responsive genes under various stress conditions.

  8. Mild oxidative stress is beneficial for sperm telomere length maintenance

    PubMed Central

    Mishra, Swetasmita; Kumar, Rajeev; Malhotra, Neena; Singh, Neeta; Dada, Rima

    2016-01-01

    AIM: To evaluate telomere length in sperm DNA and its correlation with oxidative stress (normal, mild, severe). METHODS: The study included infertile men (n = 112) and age matched fertile controls (n = 102). The average telomere length from the sperm DNA was measured using a quantitative real time PCR based assay. Seminal reactive oxygen species (ROS) and 8-Isoprostane (8-IP) levels were measured by chemiluminescence assay and ELISA respectively. RESULTS: Average sperm telomere length in infertile men and controls was 0.609 ± 0.15 and 0.789 ± 0.060, respectively (P < 0.0001). Seminal ROS levels in infertile was higher [66.61 ± 28.32 relative light units (RLU)/s/million sperm] than in controls (14.04 ± 10.67 RLU/s/million sperm) (P < 0.0001). The 8-IP level in infertile men was significantly higher (421.55 ± 131.29 pg/mL) than in controls (275.94 ± 48.13 pg/mL) (P < 0.001). When correlated to oxidative stress, in normal range of oxidative stress (ROS, 0-21.3 RLU/s/million sperm) the average telomere length in cases was 0.663 ± 0.14, in mild oxidative stress (ROS, 21.3-35 RLU/s/million sperm) it was elevated (0.684 ± 0.12) and in severe oxidative stress (ROS > 35 RLU/s/million sperm) average telomere length was decreased to 0.595 ± 0.15. CONCLUSION: Mild oxidative stress results in lengthening of telomere length, but severe oxidative stress results in shorter telomeres. Although telomere maintenance is a complex trait, the study shows that mild oxidative stress is beneficial in telomere length maintenance and thus a delicate balance needs to be established to maximize the beneficial effects of free radicals and prevent harmful effects of supra physiological levels. Detailed molecular evaluation of telomere structure, its correlation with oxidative stress would aid in elucidating the cause of accelerated telomere length attrition. PMID:27376021

  9. Diffusible Factors Secreted by Glioblastoma and Medulloblastoma Cells Induce Oxidative Stress in Bystander Neural Stem Progenitors

    PubMed Central

    Sharma, Neha; Colangelo, Nicholas W.; de Toledo, Sonia M.

    2016-01-01

    Harmful effects that alter the homeostasis of neural stem or progenitor cells (NSPs) can affect regenerative processes in the central nervous system. We investigated the effect of soluble factors secreted by control or 137Cs-γ-irradiated glioblastoma or medulloblastoma cells on redox-modulated endpoints in recipient human NSPs. Growth medium harvested from the nonirradiated brain tumor cells, following 24 h of growth, induced prominent oxidative stress in recipient NSPs as judged by overall increases in mitochondrial superoxide radical levels (p < .001), activation of c-jun N-terminal kinase, and decrease in the active form of FoxO3a. The induced oxidative stress was associated with phosphorylation of p53 on serine 15, a marker of DNA damage, induction of the cyclin-cyclin dependent kinase inhibitors p21Waf1 and p27Kip1, and perturbations in cell cycle progression (p < .001). These changes were also associated with increased apoptosis as determined by enhanced annexin V staining (p < .001) and caspase 8 activation (p < .05) and altered expression of critical regulators of self-renewal, proliferation, and differentiation. Exposure of the tumor cells to radiation only slightly altered the induced oxidative changes in the bystander NSPs, except for medium from irradiated medulloblastoma cells that was more potent at inducing apoptosis in the NSPs than medium from nonirradiated cells (p < .001). The elucidation of such stressful bystander effects provides avenues to understand the biochemical events underlying the development or exacerbation of degenerative outcomes associated with brain cancers. It is also relevant to tissue culture protocols whereby growth medium conditioned by tumor cells is often used to support the growth of stem cells. PMID:27511909

  10. Oxidative stress in the oral cavity: sources and pathological outcomes.

    PubMed

    Avezov, Katia; Reznick, Abraham Z; Aizenbud, Dror

    2015-04-01

    Oxidative stress (OS), an imbalance in the oxidant-antioxidant equilibrium, is thought to be involved in the development of many seemingly unrelated diseases. Oral cavity tissues are a unique environment constantly exposed to internal and external compounds and material hazards as almost no other part of the human body. Some of the compounds are capable of generating OS. Here, the main groups of endogenous as well as exogenous OS sources are presented, followed by their oxidative effect on the salivary contents and function. The oxidative mechanisms in oral cells and their pathologic influence are also discussed.

  11. Relationship of oxidative stress and endothelial dysfunction in sleep apnoea.

    PubMed

    Jurado-Gámez, B; Fernandez-Marin, M C; Gómez-Chaparro, J L; Muñoz-Cabrera, L; Lopez-Barea, J; Perez-Jimenez, F; Lopez-Miranda, J

    2011-04-01

    The aim of the present study was to evaluate ischaemic reactive hyperaemia (IRH) in obstructive sleep apnoea (OSA) and its relationship with oxidative stress. We studied 69 consecutive patients referred to our Sleep Unit (Reina Sofia University Hospital, Cordoba, Spain). Patients with chronic diseases or those taking medication were excluded. IRH was assessed before and after polysomnography. Morning IRH and oxidative stress markers were compared between patients with (apnoea-hypopnoea index (AHI) ≥ 5) and without (AHI < 5) OSA. Measurements were repeated in 25 severe OSA patients after continuous positive airway pressure (CPAP) therapy. We included 46 OSA patients (mean ± sd AHI 49 ± 32.1) and 23 non-OSA subjects (AHI 3 ± 0.9). The OSA patients showed a significant worsening of morning IRH, and a significant increase in malondialdehyde and 8-hydroxydeoxyguanosine levels. Only the oxygen desaturation index independently explained morning IRH, while malondialdehyde levels showed a weak effect on IRH. In severe OSA patients, IRH improved significantly after CPAP treatment, as did malondialdehyde, 8-hydroxydeoxyguanosine and protein carbonyl levels. In OSA patients, endothelial dysfunction and oxidative stress were observed, and IRH worsened after sleep. The increase in oxidative stress was not associated with IRH, while intermittent hypoxia was strongly associated with IRH. In severe OSA patients, CPAP treatment improved oxidative stress and endothelial function.

  12. Oxidative stress modulation in hepatitis C virus infected cells

    PubMed Central

    Lozano-Sepulveda, Sonia A; Bryan-Marrugo, Owen L; Cordova-Fletes, Carlos; Gutierrez-Ruiz, Maria C; Rivas-Estilla, Ana M

    2015-01-01

    Hepatitis C virus (HCV) replication is associated with the endoplasmic reticulum, where the virus can induce cellular stress. Oxidative cell damage plays an important role in HCV physiopathology. Oxidative stress is triggered when the concentration of oxygen species in the extracellular or intracellular environment exceeds antioxidant defenses. Cells are protected and modulate oxidative stress through the interplay of intracellular antioxidant agents, mainly glutathione system (GSH) and thioredoxin; and antioxidant enzyme systems such as superoxide dismutase, catalase, GSH peroxidase, and heme oxygenase-1. Also, the use of natural and synthetic antioxidants (vitamin C and E, N-acetylcysteine, glycyrrhizin, polyenylphosphatidyl choline, mitoquinone, quercetin, S-adenosylmethionine and silymarin) has already shown promising results as co-adjuvants in HCV therapy. Despite all the available information, it is not known how different agents with antiviral activity can interfere with the modulation of the cell redox state induced by HCV and decrease viral replication. This review describes an evidence-based consensus on molecular mechanisms involved in HCV replication and their relationship with cell damage induced by oxidative stress generated by the virus itself and cell antiviral machinery. It also describes some molecules that modify the levels of oxidative stress in HCV-infected cells. PMID:26692473

  13. Role of Magnesium in Oxidative Stress in Individuals with Obesity.

    PubMed

    Morais, Jennifer Beatriz Silva; Severo, Juliana Soares; Santos, Loanne Rocha Dos; de Sousa Melo, Stéfany Rodrigues; de Oliveira Santos, Raisa; de Oliveira, Ana Raquel Soares; Cruz, Kyria Jayanne Clímaco; do Nascimento Marreiro, Dilina

    2017-03-01

    Adipose tissue is considered an endocrine organ that promotes excessive production of reactive oxygen species when in excess, thus contributing to lipid peroxidation. Magnesium deficiency contributes to the development of oxidative stress in obese individuals, as this mineral plays a role as an antioxidant, participates as a cofactor of several enzymes, maintains cell membrane stability and mitigates the effects of oxidative stress. The objective of this review is to bring together updated information on the participation of magnesium in the oxidative stress present in obesity. We conducted a search of articles published in the PubMed, SciELO and LILACS databases, using the keywords 'magnesium', 'oxidative stress', 'malondialdehyde', 'superoxide dismutase', 'glutathione peroxidase', 'reactive oxygen species', 'inflammation' and 'obesity'. The studies show that obese subjects have low serum concentrations of magnesium, as well as high concentrations of oxidative stress marker in these individuals. Furthermore, it is evident that the adequate intake of magnesium contributes to its appropriate homeostasis in the body. Thus, this review of current research can help define the need for intervention with supplementation of this mineral for the prevention and treatment of disorders associated with this chronic disease.

  14. Oxidative stress induces mitochondrial fragmentation in frataxin-deficient cells

    SciTech Connect

    Lefevre, Sophie; Sliwa, Dominika; Rustin, Pierre; Camadro, Jean-Michel; Santos, Renata

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer Yeast frataxin-deficiency leads to increased proportion of fragmented mitochondria. Black-Right-Pointing-Pointer Oxidative stress induces complete mitochondrial fragmentation in {Delta}yfh1 cells. Black-Right-Pointing-Pointer Oxidative stress increases mitochondrial fragmentation in patient fibroblasts. Black-Right-Pointing-Pointer Inhibition of mitochondrial fission in {Delta}yfh1 induces oxidative stress resistance. -- Abstract: Friedreich ataxia (FA) is the most common recessive neurodegenerative disease. It is caused by deficiency in mitochondrial frataxin, which participates in iron-sulfur cluster assembly. Yeast cells lacking frataxin ({Delta}yfh1 mutant) showed an increased proportion of fragmented mitochondria compared to wild-type. In addition, oxidative stress induced complete fragmentation of mitochondria in {Delta}yfh1 cells. Genetically controlled inhibition of mitochondrial fission in these cells led to increased resistance to oxidative stress. Here we present evidence that in yeast frataxin-deficiency interferes with mitochondrial dynamics, which might therefore be relevant for the pathophysiology of FA.

  15. Cellular Mechanisms of Oxidative Stress and Action in Melanoma.

    PubMed

    Venza, Mario; Visalli, Maria; Beninati, Concetta; De Gaetano, Giuseppe Valerio; Teti, Diana; Venza, Isabella

    2015-01-01

    Most melanomas occur on the skin, but a small percentage of these life-threatening cancers affect other parts of the body, such as the eye and mucous membranes, including the mouth. Given that most melanomas are caused by ultraviolet radiation (UV) exposure, close attention has been paid to the impact of oxidative stress on these tumors. The possibility that key epigenetic enzymes cannot act on a DNA altered by oxidative stress has opened new perspectives. Therefore, much attention has been paid to the alteration of DNA methylation by oxidative stress. We review the current evidence about (i) the role of oxidative stress in melanoma initiation and progression; (ii) the mechanisms by which ROS influence the DNA methylation pattern of transformed melanocytes; (iii) the transformative potential of oxidative stress-induced changes in global and/or local gene methylation and expression; (iv) the employment of this epimutation as a biomarker for melanoma diagnosis, prognosis, and drug resistance evaluation; (v) the impact of this new knowledge in clinical practice for melanoma treatment.

  16. Cellular Mechanisms of Oxidative Stress and Action in Melanoma

    PubMed Central

    Venza, Mario; Visalli, Maria; Beninati, Concetta; De Gaetano, Giuseppe Valerio; Teti, Diana; Venza, Isabella

    2015-01-01

    Most melanomas occur on the skin, but a small percentage of these life-threatening cancers affect other parts of the body, such as the eye and mucous membranes, including the mouth. Given that most melanomas are caused by ultraviolet radiation (UV) exposure, close attention has been paid to the impact of oxidative stress on these tumors. The possibility that key epigenetic enzymes cannot act on a DNA altered by oxidative stress has opened new perspectives. Therefore, much attention has been paid to the alteration of DNA methylation by oxidative stress. We review the current evidence about (i) the role of oxidative stress in melanoma initiation and progression; (ii) the mechanisms by which ROS influence the DNA methylation pattern of transformed melanocytes; (iii) the transformative potential of oxidative stress-induced changes in global and/or local gene methylation and expression; (iv) the employment of this epimutation as a biomarker for melanoma diagnosis, prognosis, and drug resistance evaluation; (v) the impact of this new knowledge in clinical practice for melanoma treatment. PMID:26064422

  17. Phloroglucinol Attenuates Free Radical-induced Oxidative Stress

    PubMed Central

    So, Mi Jung; Cho, Eun Ju

    2014-01-01

    The protective role of phloroglucinol against oxidative stress and stress-induced premature senescence (SIPS) was investigated in vitro and in cell culture. Phloroglucinol had strong and concentration-dependent radical scavenging effects against nitric oxide (NO), superoxide anions (O2−), and hydroxyl radicals. In this study, free radical generators were used to induce oxidative stress in LLC-PK1 renal epithelial cells. Treatment with phloroglucinol attenuated the oxidative stress induced by peroxyl radicals, NO, O2−, and peroxynitrite. Phloroglucinol also increased cell viability and decreased lipid peroxidation in a concentration-dependent manner. WI-38 human diploid fibroblast cells were used to investigate the protective effect of phloroglucinol against hydrogen peroxide (H2O2)-induced SIPS. Phloroglucinol treatment attenuated H2O2-induced SIPS by increasing cell viability and inhibited lipid peroxidation, suggesting that treatment with phloroglucinol should delay the aging process. The present study supports the promising role of phloroglucinol as an antioxidative agent against free radical-induced oxidative stress and SIPS. PMID:25320709

  18. Arterial Stiffness, Oxidative Stress, and Smoke Exposure in Wildland Firefighters

    PubMed Central

    Gaughan, Denise M.; Siegel, Paul D.; Hughes, Michael D.; Chang, Chiung-Yu; Law, Brandon F.; Campbell, Corey R.; Richards, Jennifer C.; Kales, Stefanos F.; Chertok, Marcia; Kobzik, Lester; Nguyen, Phuongson; O’Donnell, Carl R.; Kiefer, Max; Wagner, Gregory R.; Christiani, David C.

    2015-01-01

    Objectives To assess the association between exposure, oxidative stress, symptoms, and cardiorespiratory function in wildland firefighters. Methods We studied two Interagency Hotshot Crews with questionnaires, pulse wave analysis for arterial stiffness, spirometry, urinary 8-iso-prostaglandin F2α (8-isoprostane) and 8-hydroxy-2′-deoxyguanosine (8-OHdG), and the smoke exposure marker (urinary levoglucosan). Arterial stiffness was assessed by examining levels of the aortic augmentation index, expressed as a percentage. An oxidative stress score comprising the average of z-scores created for 8-OHdG and 8-isoprostane was calculated. Results Mean augmentation index % was higher for participants with higher oxidative stress scores after adjusting for smoking status. Specifically for every one unit increase in oxidative stress score the augmentation index % increased 10.5% (95% CI: 2.5, 18.5%). Higher mean lower respiratory symptom score was associated with lower percent predicted forced expiratory volume in one second/forced vital capacity. Conclusions Biomarkers of oxidative stress may serve as indicators of arterial stiffness in wildland firefighters. PMID:24909863

  19. Combination effects of amphetamines under hyperthermia - the role played by oxidative stress.

    PubMed

    da Silva, Diana Dias; Silva, Elisabete; Carmo, Helena

    2014-06-01

    Rise in body temperature is a life-threatening consequence of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) abuse. We evaluated the impact of hyperthermia on the cytotoxicity of combinations of MDMA and three other amphetamines, often co-ingested. For this, Hep G2 cells were exposed to MDMA, d-amphetamine, methamphetamine and 4-methylthioamphetamine, individually or combined, at 40.5 °C. The results were compared with normothermia data (37.0 °C). Mixture additivity expectations were calculated by independent action and concentration addition (CA) models. To delineate the mechanism(s) underlying the elicited effects, a range of stress endpoints was evaluated, including quantification of reactive oxygen/nitrogen species (ROS/RNS), lipid peroxidation, reduced/oxidized glutathione (GSH/GSSG), ATP and mitochondrial membrane potential (Δψm) changes. Our data show that, in hyperthermia, amphetamines acted additively and mixture effects were accurately predicted by CA. At 40.5 °C, even slight increases in the concentrations of each drug/mixture promoted significant rises in cytotoxicity, which quickly shifted from roughly undetectable to maximal mortality. Additionally, the increase of RNS/ROS production, decrease of GSH, ATP depletion and mitochondrial impairment were exacerbated under hyperthermia. Importantly, when equieffective cytotoxic concentrations of the mixture and individual amphetamines were compared for all tested stress endpoints, mixture effects did not deviate from those elicited by individual treatments, suggesting that these amphetamines have a similar mode of action, which is not altered in combination. Concluding, our data indicate that amphetamine mixtures produce deleterious effects, even when individual drugs are combined at negligible concentrations. These effects are strongly exacerbated in hyperthermia, emphasizing the potential increased risks of ecstasy intake, especially when hyperthermia occurs concurrently with polydrug abuse.

  20. Aluminum Induces Oxidative Stress Genes in Arabidopsis thaliana1

    PubMed Central

    Richards, Keith D.; Schott, Eric J.; Sharma, Yogesh K.; Davis, Keith R.; Gardner, Richard C.

    1998-01-01

    Changes in gene expression induced by toxic levels of Al were characterized to investigate the nature of Al stress. A cDNA library was constructed from Arabidopsis thaliana seedlings treated with Al for 2 h. We identified five cDNA clones that showed a transient induction of their mRNA levels, four cDNA clones that showed a longer induction period, and two down-regulated genes. Expression of the four long-term-induced genes remained at elevated levels for at least 48 h. The genes encoded peroxidase, glutathione-S-transferase, blue copper-binding protein, and a protein homologous to the reticuline:oxygen oxidoreductase enzyme. Three of these genes are known to be induced by oxidative stresses and the fourth is induced by pathogen treatment. Another oxidative stress gene, superoxide dismutase, and a gene for Bowman-Birk protease inhibitor were also induced by Al in A. thaliana. These results suggested that Al treatment of Arabidopsis induces oxidative stress. In confirmation of this hypothesis, three of four genes induced by Al stress in A. thaliana were also shown to be induced by ozone. Our results demonstrate that oxidative stress is an important component of the plant's reaction to toxic levels of Al. PMID:9449849

  1. Acute exercise and oxidative stress: a 30 year history

    PubMed Central

    Fisher-Wellman, Kelsey; Bloomer, Richard J

    2009-01-01

    The topic of exercise-induced oxidative stress has received considerable attention in recent years, with close to 300 original investigations published since the early work of Dillard and colleagues in 1978. Single bouts of aerobic and anaerobic exercise can induce an acute state of oxidative stress. This is indicated by an increased presence of oxidized molecules in a variety of tissues. Exercise mode, intensity, and duration, as well as the subject population tested, all can impact the extent of oxidation. Moreover, the use of antioxidant supplements can impact the findings. Although a single bout of exercise often leads to an acute oxidative stress, in accordance with the principle of hormesis, such an increase appears necessary to allow for an up-regulation in endogenous antioxidant defenses. This review presents a comprehensive summary of original investigations focused on exercise-induced oxidative stress. This should provide the reader with a well-documented account of the research done within this area of science over the past 30 years. PMID:19144121

  2. Chronic unpredictable stress deteriorates the chemopreventive efficacy of pomegranate through oxidative stress pathway.

    PubMed

    Hasan, Shirin; Suhail, Nida; Bilal, Nayeem; Ashraf, Ghulam Md; Zaidi, Syed Kashif; AlNohair, Sultan; Banu, Naheed

    2016-05-01

    Chronic unpredictable stress (CUS) can influence the risk and progression of cancer through increased oxidative stress. Pomegranate is known to protect carcinogenesis through its anti-oxidative properties. This study is carried out to examine whether CUS affects the chemopreventive potential of pomegranate through oxidative stress pathway. Role of CUS on early stages of 7, 12 dimethyl benz(a) anthracene (DMBA) induced carcinogenesis, and its pre-exposure effect on chemopreventive efficacy of pomegranate juice (PJ) was examined in terms of in vivo antioxidant and biochemical parameters in Swiss albino rats. Rats were divided in various groups and were subjected to CUS paradigm, DMBA administration (65 mg/kg body weight, single dose), and PJ treatment. Exposure to stress (alone) and DMBA (alone) led to increased oxidative stress by significantly decreasing the antioxidant enzymes activities and altering the glutathione (GSH), malondialdehyde (MDA), glutamate oxaloacetate transaminase (GOT), and glutamate pyruvate transaminase (GPT) levels. A significant increase in DNA damage demonstrated by comet assay was seen in the liver cells. Stress exposure to DMBA-treated rats further increased the oxidative stress and disturbed the biochemical parameters as compared to DMBA (alone)-treated rats. Chemoprevention with PJ in DMBA (alone)-treated rats restored the altered parameters. However, in the pre-stress DMBA-treated rats, the overall antioxidant potential of PJ was significantly diminished. Our results indicate that chronic stress not only increases the severity of carcinogenesis but also diminishes the anti-oxidative efficacy of PJ. In a broader perspective, special emphasis should be given to stress management and healthy diet during cancer chemoprevention.

  3. Oxidative Stress in Glaucomatous Neurodegeneration: Mechanisms and Consequences

    PubMed Central

    Tezel, Gülgün

    2007-01-01

    Reactive oxygen species (ROS) are generated as by-products of cellular metabolism, primarily in the mitochondria. Although ROS are essential participants in cell signaling and regulation, when their cellular production overwhelms the intrinsic antioxidant capacity, damage to cellular macromolecules such as DNA, proteins, and lipids ensues. Such a state of “oxidative stress” is thought to contribute to the pathogenesis of a number of neurodegenerative diseases. Growing evidence supports the involvement of oxidative stress as a common component of glaucomatous neurodegeneration in different subcellular compartments of retinal ganglion cells (RGCs). Besides the evidence of direct cytotoxic consequences leading to RGC death, it also seems highly possible that ROS are involved in signaling RGC death by acting as a second messenger and/or modulating protein function by redox modifications of downstream effectors through enzymatic oxidation of specific amino acid residues. Different studies provide cumulating evidence, which supports the association of ROS with different aspects of the neurodegenerative process. Oxidative protein modifications during glaucomatous neurodegeneration increase neuronal susceptibility to damage and also lead to glial dysfunction. Oxidative stress-induced dysfunction of glial cells may contribute to spreading neuronal damage by secondary degeneration. Oxidative stress also promotes the accumulation of advanced glycation end products in glaucomatous tissues. It is also evident that oxidative stress takes part in the activation of immune response during glaucomatous neurodegeneration, as ROS stimulate the antigen presenting ability of glial cells and also function as co-stimulatory molecules during antigen presentation. By discussing current evidence, this review provides a broad perspective on cellular mechanisms and potential consequences of oxidative stress in glaucoma. PMID:16962364

  4. Enhanced nitric oxide generation from nitric oxide synthases as the cause of increased peroxynitrite formation during acute restraint stress: Effects on carotid responsiveness to angiotensinergic stimuli in type-1 diabetic rats.

    PubMed

    Moreira, Josimar D; Pernomian, Larissa; Gomes, Mayara S; Moreira, Rafael P; do Prado, Alejandro F; da Silva, Carlos H T P; de Oliveira, Ana M

    2016-07-15

    Diabetes mellitus is associated with reactive oxygen and nitrogen species accumulation. Behavioral stress increases nitric oxide production, which may trigger a massive impact on vascular cells and accelerate cardiovascular complications under oxidative stress conditions such as Diabetes. For this study, type-1 Diabetes mellitus was induced in Wistar rats by intraperitoneal injection of streptozotocin. After 28 days, cumulative concentration-response curves for angiotensin II were obtained in endothelium-intact carotid rings from diabetic rats that underwent to acute restraint stress for 3h. The contractile response evoked by angiotensin II was increased in carotid arteries from diabetic rats. Acute restraint stress did not alter angiotensin II-induced contraction in carotid arteries from normoglycaemic rats. However acute stress combined with Diabetes increased angiotensin II-induced contraction in carotid rings. Western blot experiments and the inhibition of nitric oxide synthases in functional assays showed that neuronal, endothelial and inducible nitric oxide synthase isoforms contribute to the increased formation of peroxynitrite and contractile hyperreactivity to angiotensin II in carotid rings from stressed diabetic rats. In summary, these findings suggest that the increased superoxide anion generation in carotid arteries from diabetic rats associated to the increased local nitric oxide synthases expression and activity induced by acute restrain stress were responsible for exacerbating the local formation of peroxynitrite and the contraction induced by angiotensin II.

  5. Nonezymatic formation of succinate in mitochondria under oxidative stress.

    PubMed

    Fedotcheva, Nadezhda I; Sokolov, Alexander P; Kondrashova, Mariya N

    2006-07-01

    The products of the reactions of mitochondrial 2-oxo acids with hydrogen peroxide and tert-butyl hydroperoxide (tert-BuOOH) were studied in a chemical system and in rat liver mitochondria. It was found by HPLC that the decarboxylation of alpha-ketoglutarate (KGL), pyruvate (PYR), and oxaloacetate (OA) by both oxidants results in the formation of succinate, acetate, and malonate, respectively. The two latter products do not metabolize in rat liver mitochondria, whereas succinate is actively oxidized, and its nonenzymatic formation from KGL may shunt the tricarboxylic acid (TCA) cycle upon inactivation of alpha-ketoglutarate dehydrogenase (KGDH) under oxidative stress, which is inherent in many diseases and aging. The occurrence of nonenzymatic oxidation of KGL in mitochondria was established by an increase in the CO(2) and succinate levels in the presence of the oxidants and inhibitors of enzymatic oxidation. H(2)O(2) and menadione as an inductor of reactive oxygen species (ROS) caused the formation of CO(2) in the presence of sodium azide and the production of succinate, fumarate, and malate in the presence of rotenone. These substrates were also formed from KGL when mitochondria were incubated with tert-BuOOH at concentrations that completely inhibit KGDH. The nonenzymatic oxidation of KGL can support the TCA cycle under oxidative stress, provided that KGL is supplied via transamination. This is supported by the finding that the strong oxidant such as tert-BuOOH did not impair respiration and its sensitivity to the transaminase inhibitor aminooxyacetate when glutamate and malate were used as substrates. The appearance of two products, KGL and fumarate, also favors the involvement of transamination. Thus, upon oxidative stress, nonenzymatic decarboxylation of KGL and transamination switch the TCA cycle to the formation and oxidation of succinate.

  6. Novel biomarker pipeline to probe the oxidation sites and oxidation degrees of hemoglobin in bovine erythrocytes exposed to oxidative stress.

    PubMed

    Zong, Wansong; Wang, Xiaoning; Yang, Chuanxi; Du, Yonggang; Sun, Weijun; Xu, Zhenzhen

    2016-06-01

    Research on biomarkers for protein oxidation might give insight into the mechanistic mode of oxidative stress. In the work present here, a novel pipeline was established to probe the oxidation mechanism of bovine hemoglobin (Hb) with its oxidation products serving as the biomarkers. Reactive oxygen species generated by irradiation were used to mimic oxidative stress conditions to oxidize Hb in bovine erythrocytes. After Hb extraction and digestion, oxidized peptides in the tryptic fragments were assigned by comparison with the extracted ion chromatography spectra of native peptide from the control sample. Subsequent tandem mass spectrometry analysis of these peptides proved that oxidation was limited to partially exposed amino acid residues (α-Phe36 , β-Met1 , β-Trp14 , for instance) in Hb. Quantitation analysis on these oxidized peptides showed that oxidation degrees of target sites had positive correlations with the extended oxidation dose and the oxidation processes were also controlled by residues types. Compared with the conventional protein carbonyl assay, the identified oxidized products were feasibility biomarkers for Hb oxidation, indicating that the proposed biomarker pipeline was suitable to provide specific and valid information for protein oxidation. Copyright © 2015 John Wiley & Sons, Ltd.

  7. The Mismetallation of Enzymes during Oxidative Stress*

    PubMed Central

    Imlay, James A.

    2014-01-01

    Mononuclear iron enzymes can tightly bind non-activating metals. How do cells avoid mismetallation? The model bacterium Escherichia coli may control its metal pools so that thermodynamics favor the correct metallation of each enzyme. This system is disrupted, however, by superoxide and hydrogen peroxide. These species oxidize ferrous iron and thereby displace it from many iron-dependent mononuclear enzymes. Ultimately, zinc binds in its place, confers little activity, and imposes metabolic bottlenecks. Data suggest that E. coli compensates by using thiols to extract the zinc and by importing manganese to replace the catalytic iron atom. Manganese resists oxidants and provides substantial activity. PMID:25160623

  8. Oxidative stress, circulating antioxidants, and dietary preferences in songbirds.

    PubMed

    Alan, Rebecca R; McWilliams, Scott R

    2013-03-01

    Oxidative stress is an unavoidable consequence of metabolism and increases during intensive exercise. This is especially problematic for migratory birds that metabolize fat to fuel long-distance flight. Birds can mitigate damage by increasing endogenous antioxidants (e.g. uric acid) or by consuming dietary antioxidants (e.g. tocopherol). During flight, birds may increase protein catabolism of lean tissue which may increase circulating uric acid and many birds also consume an antioxidant-rich frugivorous diet during autumn migration. We evaluated three related hypotheses in a migratory passerine: (1) protein consumption is positively related to circulating antioxidants, (2) a dietary oxidative stressor [i.e. polyunsaturated fatty acid (PUFA)] influences antioxidant capacity and oxidative damage, and (3) oxidative stress influences dietary antioxidant preferences. White-throated Sparrows (Zonotrichia albicollis) consuming a high protein diet increased circulating uric acid; however, uric acid, antioxidant capacity, and oxidative stress did not differ between birds consuming a high PUFA versus a low PUFA diet, despite increased oxidative damage in high PUFA birds. Birds did not prefer antioxidant-rich diets even when fed high PUFA, low protein. We conclude that White-throated Sparrows successfully mitigated oxidative damage associated with a high PUFA diet and mounted an endogenous antioxidant response independent of uric acid, other circulating antioxidants, and dietary antioxidants.

  9. Cold defence responses: the role of oxidative stress.

    PubMed

    Blagojevic, Dusko P; Grubor-Lajsic, Gordana N; Spasic, Mihajlo B

    2011-01-01

    Low temperatures provoke increased production of heat accompanied by increased respiration, oxygen consumption and the production of partially reduced oxygen species called ROS. ROS induce different forms of cellular oxidative damage, disturb the redox state and can change the activity of several metabolic enzymes. Organisms have developed a functionally connected set of anti-oxidant enzymes and low molecular mass compounds (together termed the ADS) that metabolise primary ROS. If ROS production within cells overwhelms the ADS, oxidative damage arises and oxidative stress can occur. Short-term cold exposure in endotherms leads to oxidative stress. As cold exposure persists organisms develop adaptive changes toward reducing ROS production and increasing the ADS. In contrast, heterotherms and ectotherms as a normal part of their over-wintering strategy slow down metabolism, oxygen consumption and subsequently cause ROS production. Increased baseline activity of key anti-oxidant enzymes as well as 'secondary' enzymatic defence and/or glutathione levels in preparation for a putative oxidative stressful situation arising from tissue re-oxygenation seems to be the preferred evolutionary adaptation of such animals exposed to low environmental temperatures.

  10. Drought effects on carbon and nitrogen metabolism of pea nodules can be mimicked by paraquat: evidence for the occurrence of two regulation pathways under oxidative stresses.

    PubMed

    Marino, Daniel; González, Esther M; Arrese-Igor, Cesar

    2006-01-01

    Biological nitrogen fixation (BNF) is dramatically affected by environmental constraints such as water stress or heavy metals. It has been reported that these stresses induce the over-production of reactive oxygen species (ROS) and, in turn, oxidative stress that may be responsible for the above-mentioned BNF decline at the molecular level. Oxidative stress, occurring under different environmental stresses, has been widely related to physiological damage. However, a direct relationship between oxidative stress and the decline of BNF, independently from any other cellular damage resulting from adverse environmental situations, has yet to be demonstrated. In order to study the likely in vivo relationship between ROS and BNF inhibition in the legume-Rhizobium symbiosis, two paraquat (PQ) doses, 1 (LPQ) and 10 (HPQ) mmol m(-3), were applied to pea roots for 96 h in order to exacerbate ROS production. Whole-plant physiology and nodule metabolism parameters were determined every 24 h to monitor the evolution of plant responses to ROS. LPQ provoked BNF decline, which was preceded by a prior decrease in sucrose synthase (SS) activity. However, HPQ gave rise to a faster and more pronounced BNF inhibition, which coincided with a decline in SS and also with a reduction in leghaemoglobin (Lb) content. These results indicate a likely involvement of ROS in the effects of environmental stresses on BNF. Furthermore, these results support the occurrence of two regulation pathways for BNF under oxidative stress, one of these involving carbon shortage and the other involving Lb/oxygen flux.

  11. Oxidative Stress, Inflammation, and DNA Damage Responses Elicited by Silver, Titanium Dioxide, and Cerium Oxide Nanomaterials

    EPA Science Inventory

    Previous literature on the biological effects of engineered nanomaterials has focused largely on oxidative stress and inflammation endpoints without further investigating potential pathways. Here we examine time-sensitive biological response pathways affected by engineered nanoma...

  12. Oxidative stress, fibrosis, and early afterdepolarization-mediated cardiac arrhythmias.

    PubMed

    Karagueuzian, Hrayr S; Nguyen, Thao P; Qu, Zhilin; Weiss, James N

    2013-01-01

    Animal and clinical studies have demonstrated that oxidative stress, a common pathophysiological factor in cardiac disease, reduces repolarization reserve by enhancing the L-type calcium current, the late Na, and the Na-Ca exchanger, promoting early afterdepolarizations (EADs) that can initiate ventricular tachycardia and ventricular fibrillation (VT/VF) in structurally remodeled hearts. Increased ventricular fibrosis plays a key facilitatory role in allowing oxidative-stress induced EADs to manifest as triggered activity and VT/VF, since normal non-fibrotic hearts are resistant to arrhythmias when challenged with similar or higher levels of oxidative stress. The findings imply that antifibrotic therapy, in addition to therapies designed to suppress EAD formation at the cellular level, may be synergistic in reducing the risk of sudden cardiac death.

  13. Mitochondrial dysfunction and oxidative stress in aging and cancer

    PubMed Central

    Kudryavtseva, Anna V.; Krasnov, George S.; Dmitriev, Alexey A.; Alekseev, Boris Y.; Kardymon, Olga L.; Sadritdinova, Asiya F.; Fedorova, Maria S.; Pokrovsky, Anatoly V.; Melnikova, Nataliya V.; Kaprin, Andrey D.; Moskalev, Alexey A.; Snezhkina, Anastasiya V.

    2016-01-01

    Aging and cancer are the most important issues to research. The population in the world is growing older, and the incidence of cancer increases with age. There is no doubt about the linkage between aging and cancer. However, the molecular mechanisms underlying this association are still unknown. Several lines of evidence suggest that the oxidative stress as a cause and/or consequence of the mitochondrial dysfunction is one of the main drivers of these processes. Increasing ROS levels and products of the oxidative stress, which occur in aging and age-related disorders, were also found in cancer. This review focuses on the similarities between ageing-associated and cancer-associated oxidative stress and mitochondrial dysfunction as their common phenotype. PMID:27270647

  14. Oxidative stress, fibrosis, and early afterdepolarization-mediated cardiac arrhythmias

    PubMed Central

    Karagueuzian, Hrayr S.; Nguyen, Thao P.; Qu, Zhilin; Weiss, James N.

    2013-01-01

    Animal and clinical studies have demonstrated that oxidative stress, a common pathophysiological factor in cardiac disease, reduces repolarization reserve by enhancing the L-type calcium current, the late Na, and the Na-Ca exchanger, promoting early afterdepolarizations (EADs) that can initiate ventricular tachycardia and ventricular fibrillation (VT/VF) in structurally remodeled hearts. Increased ventricular fibrosis plays a key facilitatory role in allowing oxidative-stress induced EADs to manifest as triggered activity and VT/VF, since normal non-fibrotic hearts are resistant to arrhythmias when challenged with similar or higher levels of oxidative stress. The findings imply that antifibrotic therapy, in addition to therapies designed to suppress EAD formation at the cellular level, may be synergistic in reducing the risk of sudden cardiac death. PMID:23423152

  15. Discovery of biomarkers for oxidative stress based on cellular metabolomics.

    PubMed

    Wang, Ningli; Wei, Jianteng; Liu, Yewei; Pei, Dong; Hu, Qingping; Wang, Yu; Di, Duolong

    2016-07-01

    Oxidative stress has a close relationship with various pathologic physiology phenomena and the potential biomarkers of oxidative stress may provide evidence for clinical diagnosis or disease prevention. Metabolomics was employed to identify the potential biomarkers of oxidative stress. High-performance liquid chromatography-diode array detector, mass spectrometry and partial least squares discriminate analysis were used in this study. The 10, 15 and 13 metabolites were considered to discriminate the model group, vitamin E-treated group and l-glutathione-treated group, respectively. Some of them have been identified, namely, malic acid, vitamin C, reduced glutathione and tryptophan. Identification of other potential biomarkers should be conducted and their physiological significance also needs to be elaborated.

  16. Variability of oxidative stress biomarkers in hemodialysis patients.

    PubMed

    Dahwa, Rumbidzai; Fassett, Robert G; Wang, Zaimin; Briskey, David; Mallard, Alistair R; Coombes, Jeff S

    2014-03-01

    Oxidative stress biomarkers may have a role in the future to assist clinical decisions regarding the use of antioxidant therapies and their efficacy. The aims of this study were to evaluate the within and between-individual variability of plasma oxidative stress biomarkers and investigate factors affecting their variability. Plasma F2-isoprostanes and protein carbonyls were measured in 14 hemodialysis patients every 2 weeks for 10 weeks. Within-individual coefficients of variation (CVs) were isoprostanes = 30.4% (range = 6.1-66.7%) and protein carbonyls = 16.3% (8.4-29.5%). Between-individual CVs were isoprostanes = 34.4% (28.9-40.2%) and protein carbonyls = 19.5% (15.6-24.5%). There were no significant (p > 0.05) relationships between the oxidative stress biomarkers and dietary antioxidant intake, medications, clinical and demographic parameters.

  17. Transketolase counteracts oxidative stress to drive cancer development

    PubMed Central

    Xu, Iris Ming-Jing; Lai, Robin Kit-Ho; Lin, Shu-Hai; Tse, Aki Pui-Wah; Chiu, David Kung-Chun; Koh, Hui-Yu; Law, Cheuk-Ting; Wong, Chun-Ming; Cai, Zongwei; Wong, Carmen Chak-Lui; Ng, Irene Oi-Lin

    2016-01-01

    Cancer cells experience an increase in oxidative stress. The pentose phosphate pathway (PPP) is a major biochemical pathway that generates antioxidant NADPH. Here, we show that transketolase (TKT), an enzyme in the PPP, is required for cancer growth because of its ability to affect the production of NAPDH to counteract oxidative stress. We show that TKT expression is tightly regulated by the Nuclear Factor, Erythroid 2-Like 2 (NRF2)/Kelch-Like ECH-Associated Protein 1 (KEAP1)/BTB and CNC Homolog 1 (BACH1) oxidative stress sensor pathway in cancers. Disturbing the redox homeostasis of cancer cells by genetic knockdown or pharmacologic inhibition of TKT sensitizes cancer cells to existing targeted therapy (Sorafenib). Our study strengthens the notion that antioxidants are beneficial to cancer growth and highlights the therapeutic benefits of targeting pathways that generate antioxidants. PMID:26811478

  18. SYSTEMIC BUT NOT CENTRAL NERVOUS SYSTEM NITRIC OXIDE SYNTHASE INHIBITION EXACERBATES THE HYPERTENSIVE EFFECTS OF CHRONIC MELANOCORTIN-3/4 RECEPTOR ACTIVATION

    PubMed Central

    do Carmo, Jussara M.; Bassi, Mirian; da Silva, Alexandre A.; Hall, John E.

    2011-01-01

    We examined whether systemic or central nervous system (CNS) inhibition of nitric oxide (NO) synthase exacerbates the cardiovascular responses of chronic CNS melanocortin 3/4 receptor (MC3/4R) activation. Sprague-Dawley rats implanted with telemetry probes, venous catheters and intracerebroventricular (ICV) cannulae were divided in 3 groups. After control measurements, the NO synthase inhibitor L-NAME was infused (10 μg/kg/min, IV) for 17 days and starting on day 7 of L-NAME infusion the MC3/4R agonist MTII (10 ng/hr, Group 1) or saline vehicle (Group 2) was infused ICV for 10 days. A third group not treated with L-NAME also received MTII ICV. MC3/4R activation caused a greater increase in mean arterial pressure (MAP) and heart rate (HR) in rats treated with IV L-NAME (35±6 mmHg and 56±8 bpm) than L-NAME + vehicle or MTII alone (22±5 and 9±2 mmHg, and 26±14 and 27±5 bpm) despite a 58 and 50% reduction in food intake during the first 6 days of MTII infusion. To test if the amplified pressor response to MTII after L-NAME was due to a reduction in NO availability in the brain, we also infused L-NAME directly into the CNS alone or in combination with MTII. ICV infusion of L-NAME + MTII caused only ~10 mmHg increase in MAP with no change in HR, similar to the effects of ICV infusion of MTII alone, while ICV infusion of L-NAME alone had no effect on MAP. These results suggest that reduction in peripheral, but not CNS, NO production augments MAP sensitivity to CNS MC3/4R activation. PMID:21263126

  19. Bilirubin oxidation products, oxidative stress, and intracerebral hemorrhage

    PubMed Central

    Clark, J. F.; Loftspring, M.; Wurster, W. L.; Beiler, S.; Beiler, C; Wagner, K. R.; Pyne-Geithman, G. J.

    2009-01-01

    Summary Hematoma and perihematomal regions after intracerebral hemorrhage (ICH) are biochemically active environments known to undergo potent oxidizing reactions. We report facile production of bilirubin oxidation products (BOXes) via hemoglobin/Fenton reaction under conditions approximating putative in vivo conditions seen following ICH. Using a mixture of human hemoglobin, physiological buffers, unconjugated solubilized bilirubin, and molecular oxygen and/or hydrogen peroxide, we generated BOXes, confirmed by spectral signature consistent with known BOXes mixtures produced by independent chemical synthesis, as well as HPLC-MS of BOX A and BOX B. Kinetics are straightforward and uncomplicated, having initial rates around 0.002 μM bilirubin per μM hemoglobin per second under normal experimental conditions. In hematomas from porcine ICH model, we observed significant production of BOXes, malondialdehyde, and superoxide dismutase, indicating a potent oxidizing environment. BOX concentrations increased from 0.084 ± 0.01 in fresh blood to 22.24 ± 4.28 in hematoma at 72 h, and were 11.22 ± 1.90 in adjacent white matter (nmol/g). Similar chemical and analytical results are seen in ICH in vivo, indicating the hematoma is undergoing similar potent oxidations. This is the first report of BOXes production using a well-defined biological reaction and in vivo model of same. Following ICH, amounts of unconjugated bilirubin in hematoma can be substantial, as can levels of iron and hemoglobin. Oxidation of unconjugated bilirubin to yield bioactive molecules, such as BOXes, is an important discovery, expanding the role of bilirubin in pathological processes seen after ICH. PMID:19066073

  20. Honey bee (Apis mellifera) drones survive oxidative stress due to increased tolerance instead of avoidance or repair of oxidative damage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oxidative stress can lead to premature aging symptoms and cause acute mortality at higher doses in a range of organisms. Oxidative stress resistance and longevity are mechanistically and phenotypically linked: considerable variation in oxidative stress resistance exists among and within species and ...

  1. Oxidative stress and nutritional prevention in autoimmune rheumatic diseases.

    PubMed

    Sukkar, Samir G; Rossi, Edoardo

    2004-03-01

    The hypothesis that oxidative stress favours flogistic and immune processes inducing autoimmune rheumatic diseases (ARDs) and their complications is still under discussion. In this review we take into consideration both the aetiopathological role of the diet in such diseases and the possible efficacy of dietary supports as adjuvants for the usual specific therapies. Moreover, we shall examine the hypothetical pathophysiological role of oxidative stress on ARDs and their complications, the methods for its evaluation and the possibility of intervening on oxidative pathways by means of nutritional modulation. It is possible that in the future we will be able to control connective pathology by associating an immuno-modulating therapy ('re-educating') with natural products having an anti-oxidant activity to current immunosuppressive treatment (which has potentially toxic effects).

  2. The Role of Oxidative Stress in Apoptosis of Breast Cancer.

    DTIC Science & Technology

    1995-09-27

    AD GRANT NO: AT17-94-J-4296IC % ELECTED NOV 0 3 1995 TITLE: The Role of Oxidative Stress in Apoptosis of F Breast Cancer Cells PRINCIPAL INVESTIGATOR...The Role of Oxidative Stress in Apoptosis of Breast Cancer Cells DAMD17-94-J-4296 6. AUTHOR(S) Margaret M. Briehl, Ph.D. 7. PERFORMING ORGANIZATION NAME...that control apoptosis holds promise as a new approach for the treatment of breast cancer . The objective of the research project is to test the

  3. Oxidative stress and the evolutionary origins of preeclampsia.

    PubMed

    Elliot, Michael G

    2016-04-01

    In this speculative paper, I consider the relationship between oxidative stress and the evolution of placentation in eutherian mammals. I argue that epitheliochorial placentation, in which fetal tissues remain separated from maternal blood throughout gestation, has evolved as a protective mechanism against oxidative stress arising from pregnancy, particularly in species with unusually long gestation periods and unusually large placentas. Human beings comprise an unusual species that has the life history characteristics of an epitheliochorial species, but exhibits hemochorial placentation, in which fetal tissues come into direct contact with maternal blood. I argue that the risk of preeclampsia has arisen as a consequence of the failure of human beings to evolve epitheliochorial placentation.

  4. Periodontal Disease-Induced Atherosclerosis and Oxidative Stress

    PubMed Central

    Kurita-Ochiai, Tomoko; Jia, Ru; Cai, Yu; Yamaguchi, Yohei; Yamamoto, Masafumi

    2015-01-01

    Periodontal disease is a highly prevalent disorder affecting up to 80% of the global population. Recent epidemiological studies have shown an association between periodontal disease and cardiovascular disease, as oxidative stress plays an important role in chronic inflammatory diseases such as periodontal disease and cardiovascular disease. In this review, we focus on the mechanisms by which periodontopathic bacteria cause chronic inflammation through the enhancement of oxidative stress and accelerate cardiovascular disease. Furthermore, we comment on the antioxidative activity of catechin in atherosclerosis accelerated by periodontitis. PMID:26783845

  5. Overexpression of calreticulin sensitizes SERCA2a to oxidative stress.

    PubMed

    Ihara, Yoshito; Kageyama, Kan; Kondo, Takahito

    2005-04-22

    Calreticulin (CRT), a Ca(2+)-binding molecular chaperone in the endoplasmic reticulum, plays a vital role in cardiac physiology and pathology. Oxidative stress is a main cause of myocardiac disorder in the ischemic heart, but the function of CRT under oxidative stress is not fully understood. In this study, the effect of overexpression of CRT on sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA) 2a under oxidative stress was examined using myocardiac H9c2 cells transfected with the CRT gene. The in vitro activity of SERCA2a and uptake of (45)Ca(2+) into isolated microsomes were suppressed by H(2)O(2) in CRT-overexpressing cells compared with controls. Moreover, SERCA2a protein was degraded via a proteasome-dependent pathway following the formation of a complex with CRT under the stress with H(2)O(2). Thus, we conclude that overexpression of CRT enhances the inactivation and degradation of SERCA2a in the cells under oxidative stress, suggesting some pathophysiological functions of CRT in Ca(2+) homeostasis of myocardiac disease.

  6. Stress dependent oxidation of sputtered niobium and effects on superconductivity

    SciTech Connect

    David Henry, M. Wolfley, Steve; Monson, Todd; Clark, Blythe G.; Shaner, Eric; Jarecki, Robert

    2014-02-28

    We report on the suppression of room temperature oxidation of DC sputtered niobium films and the effects upon the superconductive transition temperature, T{sub c}. Niobium was sputter-deposited on silicon dioxide coated 150 mm wafers and permitted to oxidize at room temperature and pressure for up to two years. Resistivity and stress measurements indicate that tensile films greater than 400 MPa resist bulk oxidation with measurements using transmission electron microscope, electron dispersive X-ray spectroscopy, x-ray photoelectric spectroscopy, and secondary ion mass spectrometry confirming this result. Although a surface oxide, Nb{sub 2}O{sub 5}, consumed the top 6–10 nm, we measure less than 1 at. % oxygen and nitrogen in the bulk of the films after the oxidation period. T{sub c} measurements using a SQUID magnetometer indicate that the tensile films maintained a T{sub c} approaching the dirty superconductive limit of 8.4 K after two years of oxidation while maintaining room temperature sheet resistance. This work demonstrates that control over niobium film stress during deposition can prevent bulk oxidation by limiting the vertical grain boundaries ability to oxidize, prolonging the superconductive properties of sputtered niobium when exposed to atmosphere.

  7. Stress dependent oxidation of sputtered niobium and effects on superconductivity

    NASA Astrophysics Data System (ADS)

    David Henry, M.; Wolfley, Steve; Monson, Todd; Clark, Blythe G.; Shaner, Eric; Jarecki, Robert

    2014-02-01

    We report on the suppression of room temperature oxidation of DC sputtered niobium films and the effects upon the superconductive transition temperature, Tc. Niobium was sputter-deposited on silicon dioxide coated 150 mm wafers and permitted to oxidize at room temperature and pressure for up to two years. Resistivity and stress measurements indicate that tensile films greater than 400 MPa resist bulk oxidation with measurements using transmission electron microscope, electron dispersive X-ray spectroscopy, x-ray photoelectric spectroscopy, and secondary ion mass spectrometry confirming this result. Although a surface oxide, Nb2O5, consumed the top 6-10 nm, we measure less than 1 at. % oxygen and nitrogen in the bulk of the films after the oxidation period. Tc measurements using a SQUID magnetometer indicate that the tensile films maintained a Tc approaching the dirty superconductive limit of 8.4 K after two years of oxidation while maintaining room temperature sheet resistance. This work demonstrates that control over niobium film stress during deposition can prevent bulk oxidation by limiting the vertical grain boundaries ability to oxidize, prolonging the superconductive properties of sputtered niobium when exposed to atmosphere.

  8. Fluorescence lifetime imaging of endogenous biomarker of oxidative stress

    PubMed Central

    Datta, Rupsa; Alfonso-García, Alba; Cinco, Rachel; Gratton, Enrico

    2015-01-01

    Presence of reactive oxygen species (ROS) in excess of normal physiological level results in oxidative stress. This can lead to a range of pathological conditions including inflammation, diabetes mellitus, cancer, cardiovascular and neurodegenerative disease. Biomarkers of oxidative stress play an important role in understanding the pathogenesis and treatment of these diseases. A number of fluorescent biomarkers exist. However, a non-invasive and label-free identification technique would be advantageous for in vivo measurements. In this work we establish a spectroscopic method to identify oxidative stress in cells and tissues by fluorescence lifetime imaging (FLIM). We identified an autofluorescent, endogenous species with a characteristic fluorescent lifetime distribution as a probe for oxidative stress. To corroborate our hypothesis that these species are products of lipid oxidation by ROS, we correlate the spectroscopic signals arising from lipid droplets by combining FLIM with THG and CARS microscopy which are established techniques for selective lipid body imaging. Further, we performed spontaneous Raman spectral analysis at single points of the sample which provided molecular vibration information characteristics of lipid droplets. PMID:25993434

  9. Oxidative-stress-induced epigenetic changes in chronic diabetic complications.

    PubMed

    Feng, Biao; Ruiz, Michael Anthony; Chakrabarti, Subrata

    2013-03-01

    Oxidative stress plays an important role in the development and progression of chronic diabetic complications. Diabetes causes mitochondrial superoxide overproduction in the endothelial cells of both large and small vessels. This increased superoxide production causes the activation of several signal pathways involved in the pathogenesis of chronic complications. In particular, endothelial cells are major targets of glucose-induced oxidative damage in the target organs. Oxidative stress activates cellular signaling pathways and transcription factors in endothelial cells including protein kinase C (PKC), c-Jun-N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), forkhead box O (FOXO), and nuclear factor kappa-B (NF-κB). Oxidative stress also causes DNA damage and activates DNA nucleotide excision repair enzymes including the excision repair cross complimenting 1(ERCC1), ERCC4, and poly(ADP-ribose) polymerase (PARP). Augmented production of histone acetyltransferase p300, and alterations of histone deacetylases, including class III deacetylases sirtuins, are also involved in this process. Recent research has found that small noncoding RNAs, like microRNA, are a new kind of regulator associated with chronic diabetic complications. There are extensive and complicated interactions and among these molecules. The purpose of this review is to demonstrate the role of oxidative stress in the development of diabetic complications in relation to epigenetic changes such as acetylation and microRNA alterations.

  10. In vitro model suggests oxidative stress involved in keratoconus disease

    NASA Astrophysics Data System (ADS)

    Karamichos, D.; Hutcheon, A. E. K.; Rich, C. B.; Trinkaus-Randall, V.; Asara, J. M.; Zieske, J. D.

    2014-04-01

    Keratoconus (KC) affects 1:2000 people and is a disorder where cornea thins and assumes a conical shape. Advanced KC requires surgery to maintain vision. The role of oxidative stress in KC remains unclear. We aimed to identify oxidative stress levels between human corneal keratocytes (HCKs), fibroblasts (HCFs) and keratoconus cells (HKCs). Cells were cultured in 2D and 3D systems. Vitamin C (VitC) and TGF-β3 (T3) were used for 4 weeks to stimulate self-assembled extracellular matrix (ECM). No T3 used as controls. Samples were analyzed using qRT-PCR and metabolomics. qRT-PCR data showed low levels of collagen I and V, as well as keratocan for HKCs, indicating differentiation to a myofibroblast phenotype. Collagen type III, a marker for fibrosis, was up regulated in HKCs. We robustly detected more than 150 metabolites of the targeted 250 by LC-MS/MS per condition and among those metabolites several were related to oxidative stress. Lactate levels, lactate/malate and lactate/pyruvate ratios were elevated in HKCs, while arginine and glutathione/oxidized glutathione ratio were reduced. Similar patterns found in both 2D and 3D. Our data shows that fibroblasts exhibit enhanced oxidative stress compared to keratocytes. Furthermore the HKC cells exhibit the greatest level suggesting they may have a myofibroblast phenotype.

  11. The oxidative stress of Phanerochaete chrysosporium against lead toxicity.

    PubMed

    Wan, Jia; Zeng, Guangming; Huang, Danlian; Huang, Chao; Lai, Cui; Li, Ningjie; Wei, Zhen; Xu, Piao; He, Xiaoxiao; Lai, Mingyong; He, Yibin

    2015-02-01

    Among the technologies for heavy metal remediation, bioremediation technology has gained extensive attention because of its low processing costs and high efficiency. The white-rot fungus Phanerochaete chrysosporium (P. chrysosporium) which has a good tolerance to heavy metals has been widely used in the heavy metal bioremediation. In order to figure out the molecular mechanisms involved in the oxidative stress of P. chrysosporium against metal toxicity, we examined the effect of Pb(2+) on the levels of reactive oxygen species and the production of malondialdehyde. Results showed that P. chrysosporium could adjust Pb-stressed condition by regulating the unique oxidation-antioxidation process in cells and kept a balance between oxidation and antioxidation when it was threatened by a different dose of Pb(2+). Investigations into the oxidative stress of P. chrysosporium to lead could not only provide a better understanding of the relationship between lead and oxidative stress in P. chrysosporium, but also offer important informations on the development of fungal-based remediation technologies to reduce the toxic effects of lead.

  12. Muscle Aging and Oxidative Stress in Wild-Caught Shrews

    PubMed Central

    Hindle, Allyson G.; Lawler, John M.; Campbell, Kevin L.; Horning, Markus

    2010-01-01

    Red-toothed shrews (Soricidae, subfamily Soricinae) are an intriguing model system to examine the free radical theory of aging in wild mammals, given their short (<18 month) lifespan and high mass-specific metabolic rates. As muscle performance underlies both foraging ability and predator avoidance, any age-related decline should be detrimental to fitness and survival. Muscle samples of water shrews (Sorex palustris) and sympatrically distributed short-tailed shrews (Blarina brevicauda) were therefore assessed for oxidative stress markers, protective antioxidant enzymes and apoptosis. Activity levels of catalase and glutathione peroxidase increased with age in both species. Similarly, Cu,Zn-superoxide dismutase isoform content was elevated significantly in older animals of both species (increases of 60% in the water shrew, 25% in the short-tailed shrew). Only one oxidative stress marker (lipid peroxidation) was age-elevated; the others were stable or declined (4-hydroxynonenal adducts and dihydroethidium oxidation). Glutathione peroxidase activity was significantly higher in the short-tailed shrew, while catalase activity was 2× higher in water shrews. Oxidative stress indicators were on average higher in short-tailed shrews. Apoptosis occurred in <1% of myocytes examined, and did not increase with age. Within the constraints of the sample size we found evidence of protection against elevated oxidative stress in wild-caught shrews. PMID:20109576

  13. In vitro model suggests oxidative stress involved in keratoconus disease

    PubMed Central

    Karamichos, D.; Hutcheon, A. E. K.; Rich, C. B.; Trinkaus-Randall, V.; Asara, J. M.; Zieske, J. D.

    2014-01-01

    Keratoconus (KC) affects 1:2000 people and is a disorder where cornea thins and assumes a conical shape. Advanced KC requires surgery to maintain vision. The role of oxidative stress in KC remains unclear. We aimed to identify oxidative stress levels between human corneal keratocytes (HCKs), fibroblasts (HCFs) and keratoconus cells (HKCs). Cells were cultured in 2D and 3D systems. Vitamin C (VitC) and TGF-β3 (T3) were used for 4 weeks to stimulate self-assembled extracellular matrix (ECM). No T3 used as controls. Samples were analyzed using qRT-PCR and metabolomics. qRT-PCR data showed low levels of collagen I and V, as well as keratocan for HKCs, indicating differentiation to a myofibroblast phenotype. Collagen type III, a marker for fibrosis, was up regulated in HKCs. We robustly detected more than 150 metabolites of the targeted 250 by LC-MS/MS per condition and among those metabolites several were related to oxidative stress. Lactate levels, lactate/malate and lactate/pyruvate ratios were elevated in HKCs, while arginine and glutathione/oxidized glutathione ratio were reduced. Similar patterns found in both 2D and 3D. Our data shows that fibroblasts exhibit enhanced oxidative stress compared to keratocytes. Furthermore the HKC cells exhibit the greatest level suggesting they may have a myofibroblast phenotype. PMID:24714342

  14. Muscle aging and oxidative stress in wild-caught shrews.

    PubMed

    Hindle, Allyson G; Lawler, John M; Campbell, Kevin L; Horning, Markus

    2010-04-01

    Red-toothed shrews (Soricidae, subfamily Soricinae) are an intriguing model system to examine the free-radical theory of aging in wild mammals, given their short (<18months) lifespan and high mass-specific metabolic rates. As muscle performance underlies both foraging ability and predator avoidance, any age-related decline should be detrimental to fitness and survival. Muscle samples of water shrews (Sorex palustris) and sympatrically distributed short-tailed shrews (Blarina brevicauda) were therefore assessed for oxidative stress markers, protective antioxidant enzymes and apoptosis. Activity levels of catalase and glutathione peroxidase increased with age in both species. Similarly, Cu,Zn-superoxide dismutase isoform content was elevated significantly in older animals of both species (increases of 60% in the water shrew, 25% in the short-tailed shrew). Only one oxidative stress marker (lipid peroxidation) was age-elevated; the others were stable or declined (4-hydroxynonenal adducts and dihydroethidium oxidation). Glutathione peroxidase activity was significantly higher in the short-tailed shrew, while catalase activity was 2x higher in water shrews. Oxidative stress indicators were on average higher in short-tailed shrews. Apoptosis occurred in <1% of myocytes examined, and did not increase with age. Within the constraints of the sample size we found evidence of protection against elevated oxidative stress in wild-caught shrews.

  15. Epigenetic Regulation of Oxidative Stress in Ischemic Stroke

    PubMed Central

    Zhao, Haiping; Han, Ziping; Ji, Xunming; Luo, Yumin

    2016-01-01

    The prevalence and incidence of stroke rises with life expectancy. However, except for the use of recombinant tissue-type plasminogen activator, the translation of new therapies for acute stroke from animal models into humans has been relatively unsuccessful. Oxidative DNA and protein damage following stroke is typically associated with cell death. Cause-effect relationships between reactive oxygen species and epigenetic modifications have been established in aging, cancer, acute pancreatitis, and fatty liver disease. In addition, epigenetic regulatory mechanisms during stroke recovery have been reviewed, with focuses mainly on neural apoptosis, necrosis, and neuroplasticity. However, oxidative stress-induced epigenetic regulation in vascular neural networks following stroke has not been sufficiently explored. Improved understanding of the epigenetic regulatory network upon oxidative stress may provide effective antioxidant approaches for treating stroke. In this review, we summarize the epigenetic events, including DNA methylation, histone modification, and microRNAs, that result from oxidative stress following experimental stroke in animal and cell models, and the ways in which epigenetic changes and their crosstalk influence the redox state in neurons, glia, and vascular endothelial cells, helping us to understand the foregone and vicious epigenetic regulation of oxidative stress in the vascular neural network following stroke. PMID:27330844

  16. Sirt3 Protects Dopaminergic Neurons from Mitochondrial Oxidative Stress.

    PubMed

    Shi, Han; Deng, Han-Xiang; Gius, David; Schumacker, Paul T; James Surmeier, D; Ma, Yong-Chao

    2017-03-24

    Age-dependent elevation in mitochondrial oxidative stress is widely posited to be a major factor underlying the loss of substantia nigra pars compacta (SNc) dopaminergic neurons in Parkinson's disease (PD). However, mechanistic links between aging and oxidative stress are not well understood. Sirtuin-3 (Sirt3) is a mitochondrial deacetylase that could mediate this connection. Indeed, genetic deletion of Sirt3 increased oxidative stress and decreased the membrane potential of mitochondria in SNc dopaminergic neurons. This change was attributable to increased acetylation and decreased activity of manganese superoxide dismutase (MnSOD). Site directed mutagenesis of lysine 68 to glutamine (K68Q), mimicking acetylation, decreased MnSOD activity in SNc dopaminergic neurons, whereas mutagenesis of lysine 68 to arginine (K68R), mimicking deacetylation, increased activity. Introduction of K68R MnSOD rescued mitochondrial redox status and membrane potential of SNc dopaminergic neurons from Sirt3 knockouts. Moreover, deletion of DJ-1, which helps orchestrate nuclear oxidant defenses, and Sirt3 in mice led to a clear age-related loss of SNc dopaminergic neurons. Lastly, K68 acetylation of MnSOD was significantly increased in the SNc of PD patients. Taken together, our studies suggest that an age-related decline in Sirt3 protective function is a major factor underlying increasing mitochondrial oxidative stress and loss of SNc dopaminergic neurons in PD.

  17. Oxidative stress in MeHg-induced neurotoxicity

    SciTech Connect

    Farina, Marcelo; Aschner, Michael; Rocha, Joao B.T.

    2011-11-15

    Methylmercury (MeHg) is an environmental toxicant that leads to long-lasting neurological and developmental deficits in animals and humans. Although the molecular mechanisms mediating MeHg-induced neurotoxicity are not completely understood, several lines of evidence indicate that oxidative stress represents a critical event related to the neurotoxic effects elicited by this toxicant. The objective of this review is to summarize and discuss data from experimental and epidemiological studies that have been important in clarifying the molecular events which mediate MeHg-induced oxidative damage and, consequently, toxicity. Although unanswered questions remain, the electrophilic properties of MeHg and its ability to oxidize thiols have been reported to play decisive roles to the oxidative consequences observed after MeHg exposure. However, a close examination of the relationship between low levels of MeHg necessary to induce oxidative stress and the high amounts of sulfhydryl-containing antioxidants in mammalian cells (e.g., glutathione) have led to the hypothesis that nucleophilic groups with extremely high affinities for MeHg (e.g., selenols) might represent primary targets in MeHg-induced oxidative stress. Indeed, the inhibition of antioxidant selenoproteins during MeHg poisoning in experimental animals has corroborated this hypothesis. The levels of different reactive species (superoxide anion, hydrogen peroxide and nitric oxide) have been reported to be increased in MeHg-exposed systems, and the mechanisms concerning these increments seem to involve a complex sequence of cascading molecular events, such as mitochondrial dysfunction, excitotoxicity, intracellular calcium dyshomeostasis and decreased antioxidant capacity. This review also discusses potential therapeutic strategies to counteract MeHg-induced toxicity and oxidative stress, emphasizing the use of organic selenocompounds, which generally present higher affinity for MeHg when compared to the classically

  18. Stress generation in thermally grown oxide films. [oxide scale spalling from superalloy substrates

    NASA Technical Reports Server (NTRS)

    Kumnick, A. J.; Ebert, L. J.

    1981-01-01

    A three dimensional finite element analysis was conducted, using the ANSYS computer program, of the stress state in a thin oxide film thermally formed on a rectangular piece of NiCrAl alloy. The analytical results indicate a very high compressive stress in the lateral directions of the film (approximately 6200 MPa), and tensile stresses in the metal substrate that ranged from essentially zero to about 55 MPa. It was found further that the intensity of the analytically determined average stresses could be approximated reasonably well by the modification of an equation developed previously by Oxx for stresses induced into bodies by thermal gradients.

  19. Acute restraint stress induces endothelial dysfunction: role of vasoconstrictor prostanoids and oxidative stress.

    PubMed

    Carda, Ana P P; Marchi, Katia C; Rizzi, Elen; Mecawi, André S; Antunes-Rodrigues, José; Padovan, Claudia M; Tirapelli, Carlos R

    2015-01-01

    We hypothesized that acute stress would induce endothelial dysfunction. Male Wistar rats were restrained for 2 h within wire mesh. Functional and biochemical analyses were conducted 24 h after the 2-h period of restraint. Stressed rats showed decreased exploration on the open arms of an elevated-plus maze (EPM) and increased plasma corticosterone concentration. Acute restraint stress did not alter systolic blood pressure, whereas it increased the in vitro contractile response to phenylephrine and serotonin in endothelium-intact rat aortas. NG-nitro-l-arginine methyl ester (l-NAME; nitric oxide synthase, NOS, inhibitor) did not alter the contraction induced by phenylephrine in aortic rings from stressed rats. Tiron, indomethacin and SQ29548 reversed the increase in the contractile response to phenylephrine induced by restraint stress. Increased systemic and vascular oxidative stress was evident in stressed rats. Restraint stress decreased plasma and vascular nitrate/nitrite (NOx) concentration and increased aortic expression of inducible (i) NOS, but not endothelial (e) NOS. Reduced expression of cyclooxygenase (COX)-1, but not COX-2, was observed in aortas from stressed rats. Restraint stress increased thromboxane (TX)B(2) (stable TXA(2) metabolite) concentration but did not affect prostaglandin (PG)F2α concentration in the aorta. Restraint reduced superoxide dismutase (SOD) activity, whereas concentrations of hydrogen peroxide (H(2)O(2)) and reduced glutathione (GSH) were not affected. The major new finding of our study is that restraint stress increases vascular contraction by an endothelium-dependent mechanism that involves increased oxidative stress and the generation of COX-derived vasoconstrictor prostanoids. Such stress-induced endothelial dysfunction could predispose to the development of cardiovascular diseases.

  20. Restraint stress alters immune parameters and induces oxidative stress in the mouse uterus during embryo implantation.

    PubMed

    Liu, Guanhui; Dong, Yulan; Wang, Zixu; Cao, Jing; Chen, Yaoxing

    2014-12-01

    The influence of stress on embryo implantation is not well understood. Prior studies have focused on later gestational stages and the long-term impact of stress on immune function. The objective of this study is to investigate the effects of restraint stress on the immune parameters and the oxidative states of the uterus during implantation. In this study, pregnant CD1 mice were subjected to restraint stress (4 h/d) on embryonic day 1 (E1) and sacrificed on E3, E5, and E7. Maternal plasma corticosterone (CORT) secretion and implantation sites in the uterus were examined. The uterine (excluding embryos) homogenate and uterine lymphocytes were collected to examine oxidative stress states and associated immune parameters. The results demonstrated that restraint stress increased maternal plasma CORT secretion and reduced the number of implantation sites by 15.3% on E5 and by 26.1% on E7. Moreover, restraint stress decreased the density of uterine natural killer (uNK) cells in the endometrium by 22.1-47.9% and increased the density of mast cells in the myometrium by 55.6-76.9%. Restraint stress remarkably decreased the CD3(+)CD4(+) T/CD3(+)CD8(+) T cell ratio (by 26.2-28.9%) and attenuated uterine lymphocyte proliferation and secretion of cytokines. In addition, restraint stress threatened the intracellular equilibrium between oxidants and antioxidants, resulting in decreased glutathione peroxidase (GSH-PX) (32.2% and 45.7%), superoxide dismutase (SOD) (15.5% and 26.1%), and total antioxidant capacity (T-AOC) (18.4% and 18.2%) activities and increased malondialdehyde (MDA) (34.4% and 43.0%) contents on E5 and E7. In conclusion, these findings demonstrate that restraint stress causes abnormal implantation and negatively impacts immune parameters in association with oxidative stress in mice.

  1. Normoxic resuscitation after cardiac arrest protects against hippocampal oxidative stress, metabolic dysfunction, and neuronal death

    PubMed Central

    Vereczki, Viktoria; Martin, Erica; Rosenthal, Robert E; Hof, Patrick R; Hoffman, Gloria E; Fiskum, Gary

    2008-01-01

    Resuscitation and prolonged ventilation using 100% oxygen after cardiac arrest is standard clinical practice despite evidence from animal models indicating that neurologic outcome is improved using normoxic compared with hyperoxic resuscitation. This study tested the hypothesis that normoxic ventilation during the first hour after cardiac arrest in dogs protects against prelethal oxidative stress to proteins, loss of the critical metabolic enzyme pyruvate dehydrogenase complex (PDHC), and minimizes subsequent neuronal death in the hippocampus. Anesthetized beagles underwent 10 mins ventricular fibrillation cardiac arrest, followed by defibrillation and ventilation with either 21% or 100% O2. At 1 h after resuscitation, the ventilator was adjusted to maintain normal blood gas levels in both groups. Brains were perfusion-fixed at 2 h reperfusion and used for immunohistochemical measurements of hippocampal nitrotyrosine, a product of protein oxidation, and the E1α subunit of PDHC. In hyperoxic dogs, PDHC immunostaining diminished by approximately 90% compared with sham-operated dogs, while staining in normoxic animals was not significantly different from nonischemic dogs. Protein nitration in the hippocampal neurons of hyperoxic animals was 2–3 times greater than either sham-operated or normoxic resuscitated animals at 2 h reperfusion. Stereologic quantification of neuronal death at 24 h reperfusion showed a 40% reduction using normoxic compared with hyperoxic resuscitation. These results indicate that postischemic hyperoxic ventilation promotes oxidative stress that exacerbates prelethal loss of pyruvate dehydrogenase and delayed hippocampal neuronal cell death. Moreover, these findings indicate the need for clinical trials comparing the effects of different ventilatory oxygen levels on neurologic outcome after cardiac arrest. PMID:16251887

  2. Molecular and biochemical responses of Volvox carteri to oxidative stress

    NASA Astrophysics Data System (ADS)

    Lingappa, U.; Rankin-Gee, E. K.; Lera, M.; Bebour, B.; Marcu, O.

    2014-03-01

    Understanding the intracellular response to environmental stresses is a key aspect to understanding the limits of habitability for life as we know it. A wide range of relevant stressors, from heat shock to radiation, result in the intracellular production of reactive oxygen species (ROS). ROS are used physiologically as signaling molecules to cause changes in gene expression and metabolism. However, ROS, including superoxide (O2-) and peroxides, are also highly reactive molecules that cause oxidative damage to proteins, lipids and DNA. Here we studied stress response in the multicellular, eukaryotic green alga Volvox carteri, after exposure to heat shock conditions. We show that the ROS response to heat stress is paralleled by changes in photosynthetic metabolism, antioxidant enzyme activity and gene expression, and fluctuations in the elemental composition of cells. Metabolism, as measured by pulse amplitude modulated (PAM) fluorometry over two hours of heat stress, showed a linear decrease in the photosynthetic efficiency of Volvox. ROS quantification uncovered an increase in ROS in the culture medium, paralleled by a decrease in ROS within the Volvox colonies, suggesting an export mechanism is utilized to mitigate stress. Enzyme kinetics indicated an increase in superoxide dismutase (SOD) activity over the heat stress timecourse. Using X-ray fluorescence (XRF) at the Stanford Synchrotron Radiation Lightsource, we show that these changes coincide with cell-specific import/export and intracellular redistribution of transition elements and halides, suggesting that the cellular metallome is also engaged in mediating oxidative stress in Volvox.

  3. Differential thiol oxidation of the signaling proteins Akt, PTEN or PP2A determines whether Akt phosphorylation is enhanced or inhibited by oxidative stress in C2C12 myotubes derived from skeletal muscle.

    PubMed

    Tan, Pearl Lin; Shavlakadze, Tea; Grounds, Miranda D; Arthur, Peter G

    2015-05-01

    Oxidative stress, caused by excess reactive oxygen species (ROS), has been hypothesized to cause or exacerbate skeletal muscle wasting in a number of diseases and chronic conditions. ROS, such as hydrogen peroxide, have the potential to affect signal transduction pathways such as the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3 K)/Akt pathway that regulates protein synthesis. Previous studies have found contradictory outcomes for the effect of ROS on the PI3K/Akt signaling pathway, where oxidative stress can either enhance or inhibit Akt phosphorylation. The apparent contradictions could reflect differences in experimental cell types or types of ROS treatments. We replicate both effects in myotubes of cultured skeletal muscle C2C12 cells, and show that increased oxidative stress can either inhibit or enhance Akt phosphorylation. This differential response could be explained: thiol oxidation of Akt, but not the phosphatases PTEN or PP2A, caused a decline in Akt phosphorylation; whereas the thiol oxidation of Akt, PTEN and PP2A increased Akt phosphorylation. These observations indicate that a more complete understanding of the effects of oxidative stress on a signal transduction pathway comes not only from identifying the proteins susceptible to thiol oxidation, but also their relative sensitivity to ROS.

  4. Oxidative stress in alcohol-induced rat parotid sialadenosis.

    PubMed

    Campos, Sara Cristina Gonçalves; Moreira, Denise Aparecida Corrêa; Nunes, Terezinha D'Avila e Silva; Colepicolo, Pio; Brigagão, Maísa Ribeiro Pereira Lima

    2005-07-01

    This study evaluated the effect of chronic ethanol consumption on the oxidative status of rat parotid and submandibular glands. To identify the endogenous response to ethanol ingestion, the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were determined. In addition, the antioxidant alpha-tocopherol was supplied to the animals in order to estimate its action in ethanol-associated glandular damage. The thiobarbituric acid reactive substances (TBARS), and the protein carbonyl (PC) content, both markers of cellular oxidative stress on lipid and protein structures, respectively, were recorded. Animals subjected to alcohol ingestion showed a low body growth rate with concomitant enlargement of absolute and relative parotid wet weight, compared with pair-fed calorie-controlled rats. Parotid glands of ethanol-treated animals showed increased SOD and GPx activity, and alpha-tocopherol was able to reduce their activities to the control levels. TBARS and PC were enhanced after chronic ethanol treatment in rat parotids. Supplemental alpha-tocopherol suppressed the oxidative ethanol-induced damage in lipid without affecting induced protein oxidation. Submandibular glands revealed no alterations in the weight, enzymatic and oxidative parameters tested due to ethanol and/or alpha-tocopherol ingestion. These findings indicate the involvement of oxidative stress in parotid gland sialadenosis due to ethanol consumption and the capability of alpha-tocopherol to halt lipid damage, although this low-molecular antioxidant compound leads to neither increased glandular weight nor protein oxidation in ethanol-induced parotid alterations.

  5. Oxidative stress and aberrant signaling in aging and cognitive decline

    PubMed Central

    Dröge, Wulf; Schipper, Hyman M

    2007-01-01

    Brain aging is associated with a progressive imbalance between antioxidant defenses and intracellular concentrations of reactive oxygen species (ROS) as exemplified by increases in products of lipid peroxidation, protein oxidation, and DNA oxidation. Oxidative conditions cause not only structural damage but also changes in the set points of redox-sensitive signaling processes including the insulin receptor signaling pathway. In the absence of insulin, the otherwise low insulin receptor signaling is strongly enhanced by oxidative conditions. Autophagic proteolysis and sirtuin activity, in turn, are downregulated by the insulin signaling pathway, and impaired autophagic activity has been associated with neurodegeneration. In genetic studies, impairment of insulin receptor signaling causes spectacular lifespan extension in nematodes, fruit flies, and mice. The predicted effects of age-related oxidative stress on sirtuins and autophagic activity and the corresponding effects of antioxidants remain to be tested experimentally. However, several correlates of aging have been shown to be ameliorated by antioxidants. Oxidative damage to mitochondrial DNA and the electron transport chain, perturbations in brain iron and calcium homeostasis, and changes in plasma cysteine homeostasis may altogether represent causes and consequences of increased oxidative stress. Aging and cognitive decline thus appear to involve changes at multiple nodes within a complex regulatory network. PMID:17517043

  6. Age-related oxidative stress compromises endosomal proteostasis.

    PubMed

    Cannizzo, Elvira S; Clement, Cristina C; Morozova, Kateryna; Valdor, Rut; Kaushik, Susmita; Almeida, Larissa N; Follo, Carlo; Sahu, Ranjit; Cuervo, Ana Maria; Macian, Fernando; Santambrogio, Laura

    2012-07-26

    A hallmark of aging is an imbalance between production and clearance of reactive oxygen species and increased levels of oxidatively damaged biomolecules. Herein, we demonstrate that splenic and nodal antigen-presenting cells purified from aging mice accumulate oxidatively modified proteins with side-chain carbonylation, advanced glycation end products, and lipid peroxidation. Furthermore, we show that the endosomal accumulation of oxidatively modified proteins interferes with the efficient processing of exogenous antigens and degradation of macroautophagy-delivered proteins. In support of a causative role for oxidized products in the inefficient immune response, a decrease in oxidative stress improved the adaptive immune response to immunizing antigens. These findings underscore a previously unrecognized negative effect of age-dependent changes in cellular proteostasis on the immune response.

  7. Age-related Oxidative Stress Compromises Endosomal Proteostasis

    PubMed Central

    Cannizzo, Elvira S.; Clement, Cristina C.; Morozova, Kateryna; Valdor, Rut; Kaushik, Susmita; Almeida, Larissa N.; Follo, Carlo; Sahu, Ranjit; Cuervo, Ana Maria; Macian, Fernando; Santambrogio, Laura

    2012-01-01

    A hallmark of aging is an imbalance between production and clearance of reactive oxygen species and increased levels of oxidatively damaged biomolecules. Herein we demonstrate that splenic and nodal antigen presenting cells purified from old mice accumulate oxidatively modified proteins with side chain carbonylation, advanced glycation end products and lipid peroxidation. We show further that the endosomal accumulation of oxidatively modified proteins interferes with the efficient processing of exogenous antigens and degradation of macroautophagy-delivered proteins. In support of a causative role for oxidized products in the inefficient immune response, a decrease in oxidative stress improved the adaptive immune response to immunizing antigens. These findings underscore a previously unrecognized negative effect of age-dependent changes in cellular proteostasis on the immune response. PMID:22840404

  8. Oxidative stress modulates the nitric oxide defense promoted by Escherichia coli flavorubredoxin.

    PubMed

    Baptista, Joana M; Justino, Marta C; Melo, Ana M P; Teixeira, Miguel; Saraiva, Lígia M

    2012-07-01

    Mammalian cells of innate immunity respond to pathogen invasion by activating proteins that generate a burst of oxidative and nitrosative stress. Pathogens defend themselves from the toxic compounds by triggering a variety of detoxifying enzymes. Escherichia coli flavorubredoxin is a nitric oxide reductase that is expressed under nitrosative stress conditions. We report that in contrast to nitrosative stress alone, exposure to both nitrosative and oxidative stresses abolishes the expression of flavorubredoxin. Electron paramagnetic resonance (EPR) experiments showed that under these conditions, the iron center of the flavorubredoxin transcription activator NorR loses the ability to bind nitric oxide. Accordingly, triggering of the NorR ATPase activity, a requisite for flavorubredoxin activation, was impaired by treatment of the protein with the double stress. Studies of macrophages revealed that the contribution of flavorubredoxin to the survival of E. coli depends on the stage of macrophage infection and that the lack of protection observed at the early phase is related to inhibition of NorR activity by the oxidative burst. We propose that the time-dependent activation of flavorubredoxin contributes to the adaptation of E. coli to the different fluxes of hydrogen peroxide and nitric oxide to which the bacterium is subjected during the course of macrophage infection.

  9. Oxidative Stress Modulates the Nitric Oxide Defense Promoted by Escherichia coli Flavorubredoxin

    PubMed Central

    Baptista, Joana M.; Justino, Marta C.; Melo, Ana M. P.; Teixeira, Miguel

    2012-01-01

    Mammalian cells of innate immunity respond to pathogen invasion by activating proteins that generate a burst of oxidative and nitrosative stress. Pathogens defend themselves from the toxic compounds by triggering a variety of detoxifying enzymes. Escherichia coli flavorubredoxin is a nitric oxide reductase that is expressed under nitrosative stress conditions. We report that in contrast to nitrosative stress alone, exposure to both nitrosative and oxidative stresses abolishes the expression of flavorubredoxin. Electron paramagnetic resonance (EPR) experiments showed that under these conditions, the iron center of the flavorubredoxin transcription activator NorR loses the ability to bind nitric oxide. Accordingly, triggering of the NorR ATPase activity, a requisite for flavorubredoxin activation, was impaired by treatment of the protein with the double stress. Studies of macrophages revealed that the contribution of flavorubredoxin to the survival of E. coli depends on the stage of macrophage infection and that the lack of protection observed at the early phase is related to inhibition of NorR activity by the oxidative burst. We propose that the time-dependent activation of flavorubredoxin contributes to the adaptation of E. coli to the different fluxes of hydrogen peroxide and nitric oxide to which the bacterium is subjected during the course of macrophage infection. PMID:22563051

  10. Good genes, oxidative stress and condition-dependent sexual signals.

    PubMed Central

    von Schantz, T; Bensch, S; Grahn, M; Hasselquist, D; Wittzell, H

    1999-01-01

    The immune and the detoxication systems of animals are characterized by allelic polymorphisms, which underlie individual differences in ability to combat assaults from pathogens and toxic compounds. Previous studies have shown that females may improve offspring survival by selecting mates on the basis of sexual ornaments and signals that honestly reveal health. In many cases the expression of these ornaments appears to be particularly sensitive to oxidative stress. Activated immune and detoxication systems often generate oxidative stress by an extensive production of reactive metabolites and free radicals. Given that tolerance or resistance to toxic compounds and pathogens can be inherited, female choice should promote the evolution of male ornaments that reliably reveal the status of the bearers' level of oxidative stress. Hence, oxidative stress may be one important agent linking the expression of sexual ornaments to genetic variation in fitness-related traits, thus promoting the evolution of female mate choice and male sexual ornamentation, a controversial issue in evolutionary biology ever since Darwin. PMID:10081154

  11. Effect of antioxidants on the oxidative stress in cataract patients

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To determine the relationship between oxidative stress and eye disease, and the impact of antioxidant supplementation, forty subjects (50-70 y, F25, M15) were enrolled in a double blinded randomized study. Subjects were randomized to receive either 1) lutein (12 mg) or 2) lutein (12 mg) + green tea...

  12. OXIDATIVE STRESS PARTICIPATES IN PARTICULATE MATTER (PM) INDUCED LUNG INJURY

    EPA Science Inventory

    Oxidative stress participates in particulate matter (PM) induced acute lung injury.
    Elizabeth S. Roberts1, Judy L. Richards2, Kevin L. Dreher2. 1College of Veterinary Medicine, NC State University, Raleigh, NC, 2US Environmental Protection Agency, NHEERL, RTP, NC.
    Epidemiol...

  13. Oxidative stress and antioxidant status in fetal circulation in preeclampsia.

    PubMed

    Braekke, Kristin; Harsem, Nina K; Staff, Anne C

    2006-11-01

    Preeclampsia is associated with oxidative stress in maternal circulation. The purpose of this study was to explore oxidative stress and antioxidants in the fetal circulation in preeclampsia. Women with preeclampsia (n = 19) or uncomplicated pregnancies (n = 33) delivered by cesarean section were included. Blood was sampled separately from the umbilical vein and artery. 8-Iso-prostaglandin F(2alpha) (8-isoprostane), a stable product of lipid peroxidation, is a reliable marker of oxidative stress. Concentration of total 8-isoprostane in cord plasma was analyzed by gas chromatography-mass spectrometry. Antioxidant status was evaluated measuring ferric reducing ability of plasma and vitamin E. There was no difference between preeclampsia and control groups regarding median plasma concentration of 8-isoprostane in umbilical vein (955 versus 780 pg/mL, p = 0.41) or in umbilical artery (233 versus 276 pg/mL, p = 0.65). Concentration of 8-isoprostane was much higher in plasma from the umbilical vein than artery, suggesting placenta as the source of 8-isoprostane. Median ferric reducing ability of plasma concentration was higher in preeclampsia than in controls, both in the umbilical vein and artery. Median vitamin E concentration in the umbilical vein was higher in preeclampsia, but no difference was found in the umbilical artery. In conclusion, no evidence of increased oxidative stress, evaluated by 8-isoprostane concentration, was found in fetal circulation in preeclampsia.

  14. Oxidative stress responses and NRF2 in human leukaemia.

    PubMed

    Abdul-Aziz, Amina; MacEwan, David J; Bowles, Kristian M; Rushworth, Stuart A

    2015-01-01

    Oxidative stress as a result of elevated levels of reactive oxygen species (ROS) has been observed in almost all cancers, including leukaemia, where they contribute to disease development and progression. However, cancer cells also express increased levels of antioxidant proteins which detoxify ROS. This includes glutathione, the major antioxidant in human cells, which has recently been identified to have dysregulated metabolism in human leukaemia. This suggests that critical balance of intracellular ROS levels is required for cancer cell function, growth, and survival. Nuclear factor (erythroid-derived 2)-like 2 (NRF2) transcription factor plays a dual role in cancer. Primarily, NRF2 is a transcription factor functioning to protect nonmalignant cells from malignant transformation and oxidative stress through transcriptional activation of detoxifying and antioxidant enzymes. However, once malignant transformation has occurred within a cell, NRF2 functions to protect the tumour from oxidative stress and chemotherapy-induced cytotoxicity. Moreover, inhibition of the NRF2 oxidative stress pathway in leukaemia cells renders them more sensitive to cytotoxic chemotherapy. Our improved understanding of NRF2 biology in human leukaemia may permit mechanisms by which we could potentially improve future cancer therapies. This review highlights the mechanisms by which leukaemic cells exploit the NRF2/ROS response to promote their growth and survival.

  15. Stimuli-responsive electrodes detect oxidative stress and liver injury.

    PubMed

    Aran, Kiana; Parades, Jacobo; Rafi, Mohammad; Yau, Jennifer F; Acharya, Abhinav P; Zibinsky, Mikhail; Liepmann, Dorian; Murthy, Niren

    2015-02-25

    A digital point-of-care biosensor for measuring reactive oxygen species is presented based on novel reactive oxygen species responsive polymer-based electrodes. The biosensor is able to detect a drug-induced liver injury by monitoring the oxidative stress in the blood.

  16. Apoptosis modulated by oxidative stress and inflammation during obstructive nephropathy.

    PubMed

    Manucha, Walter; Vallés, Patricia G

    2012-08-01

    Kidney apoptosis and fibrosis are an inevitable outcome of progressive chronic kidney diseases where congenital obstructive nephropathy is the primary cause of the end-stage renal disease in children, and is also a major cause of renal failure in adults. The injured tubular cells linked to interstitial macrophages, and myofibroblasts produce cytokines and growth factors that promote an inflammatory state in the kidney, induce tubular cell apoptosis, and facilitate the accumulation of extracellular matrix. Angiotensin II plays a central role in the renal fibrogenesis at a very early stage leading to a rapid progression in chronic kidney disease. The increasing levels of angiotensin II induce pro-inflammatory cytokines, NF-κB activation, adhesion molecules, chemokines, growth factors, and oxidative stress. Furthermore, growing evidence reports that angiotensin II (a pro-inflammatory hormone) increases the mitochondrial oxidative stress regulating apoptosis induction. This review summarizes our understanding about possible mechanisms that contribute to apoptosis modulated by inflammation and/or oxidative stress during obstructive nephropathy. The new concept of antiinflammatory tools regulating mitochondrial oxidative stress will directly affect the inflammatory process and apoptosis. This idea could have attractive consequences in the treatment of renal and other inflammatory pathologies.

  17. Association of Lipids with Oxidative Stress Biomarkers in Subclinical Hypothyroidism

    PubMed Central

    Santi, Adriana; Duarte, Marta M. M. F.; de Menezes, Charlene C.; Loro, Vania Lucia

    2012-01-01

    Objective. The aim of the present study was to evaluate the oxidative stress biomarkers in patients with subclinical hypothyroidism (n = 20) and health controls (n = 20). Subjects and Methods. Total cholesterol (TC), triglycerides (TGs), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), thiobarbituric acid reactive substances (TBARSs), catalase (CAT), superoxide dismutase (SOD), and arylesterase (ARE) were analyzed. Results. TC, LDL-C, TBARS, and CAT were higher in subclinical hypothyroidism patients, whereas SOD did not change. Arylesterase activity was significantly lower in the SH group, compared with the control group. Correlation analyses revealed the association of lipids (TC and LDL-C) with both oxidative stress biomarkers and thyrotropin (TSH). Thyroid hormones were correlated only with triglyceride levels. In addition, TSH was significantly correlated with TBARS, CAT, and SOD. However, no significant correlations were observed after controlling TC levels. Conclusions. We found that SH patients are under increased oxidative stress manifested by reduced ARE activity and elevated lipoperoxidation and CAT activity. Secondary hypercholesterolemia to thyroid dysfunction and not hypothyroidism per se appears to be associated with oxidative stress in subclinical hypothyroidism. PMID:23251155

  18. Oxidative stress alters physiological and morphological neuronal properties.

    PubMed

    Hasan, Sonia M; Joe, Mary; Alshuaib, Waleed B

    2007-07-01

    We investigated the effects of H(2)O(2)-induced oxidative stress on the delayed-rectifier current (IK(DR)), neuronal physiological and morphological properties. Measurements were obtained from hippocampal CA1 neurons in control solution and from the same neurons after exposure to oxidative stress (short- and long-term H(2)O(2) external applications at 0.1, 1, and 10 mM). With short-term (6 min) H(2)O(2) (1 mM) treatment, IK(DR) measured in the H(2)O(2)-containing solution (778 +/- 23 pA, n=20), was smaller than that measured in the control Ca(2+)-free Hepes solution (1,112 +/- 38 pA, n=20). Coenzyme Q(10) (0.1 mM) pretreatment prevented the H(2)O(2)-induced inhibition of IK(DR). With long-term (40, 80 min) H(2)O(2) (0.1, 10 mM) treatment, the neuron lost its distinctive shape (rounded up) and the neurite almost disappeared. These results suggest that oxidative stress, which inhibits IK(DR), can alter neural activity. The morphological changes caused by H(2)O(2) support the idea that oxidative stress causes intracellular damage and compromises neural function.

  19. Mechanisms of Nanoparticle-Induced Oxidative Stress and Toxicity

    PubMed Central

    Wang, Liying

    2013-01-01

    The rapidly emerging field of nanotechnology has offered innovative discoveries in the medical, industrial, and consumer sectors. The unique physicochemical and electrical properties of engineered nanoparticles (NP) make them highly desirable in a variety of applications. However, these novel properties of NP are fraught with concerns for environmental and occupational exposure. Changes in structural and physicochemical properties of NP can lead to changes in biological activities including ROS generation, one of the most frequently reported NP-associated toxicities. 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, NP-cell interaction, and immune cell activation are responsible for ROS-mediated damage. NP-induced oxidative stress responses are torch bearers for further pathophysiological effects including genotoxicity, inflammation, and fibrosis as demonstrated by activation of associated cell signaling pathways. Since oxidative stress is a key determinant of NP-induced injury, it is necessary to characterize the ROS response resulting from NP. Through physicochemical characterization and understanding of the multiple signaling cascades activated by NP-induced ROS, a systemic toxicity screen with oxidative stress as a predictive model for NP-induced injury can be developed. PMID:24027766

  20. Oxidative Stress, DNA Repair and Prostate Cancer Risk

    DTIC Science & Technology

    2010-08-01

    progressed smoothly for all three specific aims. 15. SUBJECT TERMS microRNA ovarian cancer 16. SECURITY CLASSIFICATION OF: 17. LIMITATION... factors for prostate cancer are associated with elevated levels of ROS (advancing age, inflammation, androgen, high-fat diet), or decreased...TITLE: Oxidative Stress, DNA Repair and Prostate Cancer Risk PRINCIPAL INVESTIGATOR: Hua Zhao, Ph.D

  1. Lutein Protects RGC-5 Cells Against Hypoxia and Oxidative Stress

    PubMed Central

    Li, Suk-Yee; Lo, Amy C. Y.

    2010-01-01

    Retinal ischemia and oxidative stress lead to neuronal death in many ocular pathologies. Recently, we found that lutein, an oxy-carotenoid, protected the inner retina from ischemia/reperfusion injury. However, it is uncertain whether lutein directly protects retinal ganglion cells (RGCs). Here, an in vitro model of hypoxia and oxidative stress was used to further investigate the neuroprotective role of lutein in RGCs. Cobalt chloride (CoCl2) and hydrogen peroxide (H2O2) were added to a transformed RGC cell line, RGC-5, to induce chemical hypoxia and oxidative stress, respectively. Either lutein or vehicle was added to cultured cells. A higher cell count was observed in the lutein-treated cells compared with the vehicle-treated cells. Our data from this in vitro model revealed that lutein might protect RGC-5 cells from damage when exposed to either CoCl2-induced chemical hypoxia or H2O2-induced oxidative stress. These results suggest that lutein may play a role as a neuroprotectant. PMID:20559505

  2. Targeting Oxidative Stress for Treatment of Glaucoma and Optic Neuritis

    PubMed Central

    Kimura, Atsuko; Namekata, Kazuhiko; Guo, Xiaoli; Noro, Takahiko; Harada, Chikako

    2017-01-01

    Glaucoma is a neurodegenerative disease of the eye and it is one of the leading causes of blindness. Glaucoma is characterized by progressive degeneration of retinal ganglion cells (RGCs) and their axons, namely, the optic nerve, usually associated with elevated intraocular pressure (IOP). Current glaucoma therapies target reduction of IOP, but since RGC death is the cause of irreversible vision loss, neuroprotection may be an effective strategy for glaucoma treatment. One of the risk factors for glaucoma is increased oxidative stress, and drugs with antioxidative properties including valproic acid and spermidine, as well as inhibition of apoptosis signal-regulating kinase 1, an enzyme that is involved in oxidative stress, have been reported to prevent glaucomatous retinal degeneration in mouse models of glaucoma. Optic neuritis is a demyelinating inflammation of the optic nerve that presents with visual impairment and it is commonly associated with multiple sclerosis, a chronic demyelinating disease of the central nervous system. Although steroids are commonly used for treatment of optic neuritis, reduction of oxidative stress by approaches such as gene therapy is effective in ameliorating optic nerve demyelination in preclinical studies. In this review, we discuss oxidative stress as a therapeutic target for glaucoma and optic neuritis. PMID:28270908

  3. Reproductive Benefit of Oxidative Damage: An Oxidative Stress “Malevolence”?

    PubMed Central

    Poljsak, B.; Milisav, I.; Lampe, T.; Ostan, I.

    2011-01-01

    High levels of reactive oxygen species (ROS) compared to antioxidant defenses are considered to play a major role in diverse chronic age-related diseases and aging. Here we present an attempt to synthesize information about proximate oxidative processes in aging (relevant to free radical or oxidative damage hypotheses of aging) with an evolutionary scenario (credited here to Dawkins hypotheses) involving tradeoffs between the costs and benefits of oxidative stress to reproducing organisms. Oxidative stress may be considered a biological imperfection; therefore, the Dawkins' theory of imperfect adaptation of beings to environment was applied to the role of oxidative stress in processes like famine and infectious diseases and their consequences at the molecular level such as mutations and cell signaling. Arguments are presented that oxidative damage is not necessarily an evolutionary mistake but may be beneficial for reproduction; this may prevail over its harmfulness to health and longevity in evolution. Thus, Dawkins' principle of biological “malevolence” may be an additional biological paradigm for explaining the consequences of oxidative stress. PMID:21969876

  4. Effect of acute intradialytic strength physical exercise on oxidative stress and inflammatory responses in hemodialysis patients

    PubMed Central

    Esgalhado, Marta; Stockler-Pinto, Milena Barcza; de França Cardozo, Ludmila Ferreira Medeiros; Costa, Cinthia; Barboza, Jorge Eduardo; Mafra, Denise

    2015-01-01

    reduce oxidative stress and inflammation, and in addition, it seems to reduce plasma SOD levels, which could exacerbate the oxidative stress in HD patients. PMID:26484017

  5. Behavior of Oxidative Stress Markers in Alcoholic Liver Cirrhosis Patients

    PubMed Central

    Galicia-Moreno, Marina; Rosique-Oramas, Dorothy; Medina-Avila, Zaira; Álvarez-Torres, Tania; Falcón, Dalia; Higuera-de la tijera, Fátima; Béjar, Yadira L.; Cordero-Pérez, Paula; Muñoz-Espinosa, Linda; Pérez-Hernández, José Luis; Kershenobich, David

    2016-01-01

    Alcohol is the most socially accepted addictive substance worldwide, and its metabolism is related with oxidative stress generation. The aim of this work was to evaluate the role of oxidative stress in alcoholic liver cirrhosis (ALC). This study included 187 patients divided into two groups: ALC, classified according to Child-Pugh score, and a control group. We determined the levels of reduced and oxidized glutathione (GSH and GSSG) and the GSH/GSSG ratio by an enzymatic method in blood. Also, protein carbonyl and malondialdehyde (MDA) content were estimated in serum. MDA levels increased in proportion to the severity of damage, whereas the GSH and GSSG levels decreased and increased, respectively, at different stages of cirrhosis. There were no differences in the GSH/GSSG ratio and carbonylated protein content between groups. We also evaluated whether the active consumption of or abstinence from alcoholic beverages affected the behavior of these oxidative markers and only found differences in the MDA, GSH, and GSSG determination and the GSH/GSSG ratio. Our results suggest that alcoholic cirrhotic subjects have an increase in oxidative stress in the early stages of disease severity and that abstinence from alcohol consumption favors the major antioxidant endogen: GSH in patients with advanced disease severity. PMID:28074118

  6. Behavior of Oxidative Stress Markers in Alcoholic Liver Cirrhosis Patients.

    PubMed

    Galicia-Moreno, Marina; Rosique-Oramas, Dorothy; Medina-Avila, Zaira; Álvarez-Torres, Tania; Falcón, Dalia; Higuera-de la Tijera, Fátima; Béjar, Yadira L; Cordero-Pérez, Paula; Muñoz-Espinosa, Linda; Pérez-Hernández, José Luis; Kershenobich, David; Gutierrez-Reyes, Gabriela

    2016-01-01

    Alcohol is the most socially accepted addictive substance worldwide, and its metabolism is related with oxidative stress generation. The aim of this work was to evaluate the role of oxidative stress in alcoholic liver cirrhosis (ALC). This study included 187 patients divided into two groups: ALC, classified according to Child-Pugh score, and a control group. We determined the levels of reduced and oxidized glutathione (GSH and GSSG) and the GSH/GSSG ratio by an enzymatic method in blood. Also, protein carbonyl and malondialdehyde (MDA) content were estimated in serum. MDA levels increased in proportion to the severity of damage, whereas the GSH and GSSG levels decreased and increased, respectively, at different stages of cirrhosis. There were no differences in the GSH/GSSG ratio and carbonylated protein content between groups. We also evaluated whether the active consumption of or abstinence from alcoholic beverages affected the behavior of these oxidative markers and only found differences in the MDA, GSH, and GSSG determination and the GSH/GSSG ratio. Our results suggest that alcoholic cirrhotic subjects have an increase in oxidative stress in the early stages of disease severity and that abstinence from alcohol consumption favors the major antioxidant endogen: GSH in patients with advanced disease severity.

  7. Oxidative stress in songbirds exposed to dietary methylmercury.

    PubMed

    Henry, Katie A; Cristol, Daniel A; Varian-Ramos, Claire W; Bradley, Eric L

    2015-04-01

    Long-term, sublethal methylmercury exposure can cause reproductive depression, immune suppression, endocrine disruption and other problems in birds. We used two biomarkers to detect oxidative stress in livers of zebra finches (Taeniopygia guttata) developmentally exposed to sublethal levels of dietary methylmercury (0.0, 0.3, 0.6, 1.2, or 2.4 μg/g wet weight in diet). Our findings indicate that young adult finches exposed to environmentally relevant concentrations of mercury in ovo and through their diets, exhibited oxidative stress in their livers. We measured the ratio of the antioxidant glutathione in its reduced form (GSH) versus its oxidized form (GSSG) and the activity of the superoxide dismutase (SOD) enzyme suite. Blood total mercury served as a proxy for liver mercury concentration, and was on average 8.4 times the dietary dose (e.g., birds consuming 0.6 μg/g had blood mercury levels of ~5 μg/g on a wet weight basis). Consistent with what is known from large, aquatic bird species, there was a significant, negative relationship between GSH/GSSG ratios and tissue mercury concentrations, which is indicative of oxidative stress. This relationship was driven by a significant increase in the oxidized glutathione in the livers of birds with higher blood mercury levels. SOD activity was also found to have a significant, negative relationship with blood mercury.

  8. Cocoa phenolic extract protects pancreatic beta cells against oxidative stress.

    PubMed

    Martín, María Angeles; Ramos, Sonia; Cordero-Herrero, Isabel; Bravo, Laura; Goya, Luis

    2013-07-31

    Diabetes mellitus is associated with reductions in glutathione, supporting the critical role of oxidative stress in its pathogenesis. Antioxidant food components such as flavonoids have a protective role against oxidative stress-induced degenerative and age-related diseases. Flavonoids constitute an important part of the human diet; they can be found in most plant foods, including green tea, grapes or cocoa and possess multiple biological activities. This study investigates the chemo-protective effect of a cocoa phenolic extract (CPE) containing mainly flavonoids against oxidative stress induced by tert-butylhydroperoxide (t-BOOH) on Ins-1E pancreatic beta cells. Cell viability and oxidative status were evaluated. Ins-1E cells treatment with 5-20 μg/mL CPE for 20 h evoked no cell damage and did not alter ROS production. Addition of 50 μM t-BOOH for 2 h increased ROS and carbonyl groups content and decreased reduced glutathione level. Pre-treatment of cells with CPE significantly prevented the t-BOOH-induced ROS and carbonyl groups and returned antioxidant defences to adequate levels. Thus, Ins-1E cells treated with CPE showed a remarkable recovery of cell viability damaged by t-BOOH, indicating that integrity of surviving machineries in the CPE-treated cells was notably protected against the oxidative insult.

  9. Brain oxidative stress induced by obstructive jaundice in rats.

    PubMed

    Chroni, Elisabeth; Patsoukis, Nikolaos; Karageorgos, Nikolaos; Konstantinou, Dimitris; Georgiou, Christos

    2006-02-01

    The effect of experimental obstructive jaundice on the oxidative status of brain tissues in rats was examined. Twenty-four male Wistar rats were divided into 4 groups: Group I was the control, group II was the sham operated, and groups III and IV were bile duct ligated and killed on the 5th and the 10th day, respectively. Oxidative stress was assessed by measuring the thiol redox state (protein and nonprotein components) and lipid peroxidation level variations in samples from the cerebral cortex, midbrain, and cerebellar tissue in all animals. Results indicated the presence of oxidative stress in the jaundiced animals that was more pronounced on the 10th day as indicated by a decrease in reduced glutathione and protein thiol and an increase in protein disulphide and lipid peroxidation. A dramatic elevation of the level of total nonprotein mixed disulphide level was found specifically in the midbrain in the 10th day group. This suggests an accumulation of nonprotein disulfides other than oxidized glutathione, which remained unchanged, in this particular brain area. This study showed a correlation between experimental obstructive jaundice and the oxidative stress in the rats' brain, implying that a similar pathogenetic mechanism may play a key role in cholestatic liver disease, resulting in hepatic encephalopathy in humans.

  10. Perinatal BPA exposure induces hyperglycemia, oxidative stress and decreased adiponectin production in later life of male rat offspring.

    PubMed

    Song, Shunzhe; Zhang, Ling; Zhang, Hongyuan; Wei, Wei; Jia, Lihong

    2014-04-03

    The main object of the present study was to explore the effect of perinatal bisphenol A (BPA) exposure on glucose metabolism in early and later life of male rat offspring, and to establish the potential mechanism of BPA-induced dysglycemia. Pregnant rats were treated with either vehicle or BPA by drinking water at concentrations of 1 and 10 µg/mL BPA from gestation day 6 through the end of lactation. We measured the levels of fasting serum glucose, insulin, adiponectin and parameters of oxidative stress on postnatal day (PND) 50 and PND100 in male offspring, and adiponectin mRNA and protein expression in adipose tissue were also examined. Our results showed that perinatal exposure to 1 or 10 µg/mL BPA induced hyperglycemia with insulin resistance on PND100, but only 10 µg/mL BPA exposure had similar effects as early as PND50. In addition, increased oxidative stress and decreased adiponectin production were also observed in BPA exposed male offspring. Our findings indicated that perinatal exposure to BPA resulted in abnormal glucose metabolism in later life of male offspring, with an earlier and more exacerbated effect at higher doses. Down-regulated expression of adiponectin gene and increased oxidative stress induced by BPA may be associated with insulin resistance.

  11. Autophagy and oxidative stress in cardiovascular diseases

    PubMed Central

    Mei, Yu; Thompson, Melissa D.; Cohen, Richard A.; Tong, XiaoYong

    2014-01-01

    Autophagy is a highly conserved degradation process by which intracellular components, including soluble macromolecules (e.g. nucleic acids, proteins, carbohydrates, and lipids) and dysfunctional organelles (e.g. mitochondria, ribosomes, peroxisomes, and endoplasmic reticulum) are degraded by the lysosome. Autophagy is orchestrated by the autophagy related protein (Atg) composed protein complexes to form autophagosomes, which fuse with lysosomes to generate autolysosomes where the contents are degraded to provide energy for cell survival in response to environmental and cellular stress. Autophagy is an important player in cardiovascular disease development such as atherosclerosis, cardiac ischemia/reperfusion, cardiomyopathy, heart failure and hypertension. Autophagy in particular contributes to cardiac ischemia, hypertension and diabetes by interaction with reactive oxygen species generated in endoplasmic reticulum and mitochondria. This review highlights the dual role of autophagy in cardiovascular disease development. Full recognition of autophagy as an adaptive or maladaptive response would provide potential new strategies for cardiovascular disease prevention and management. PMID:24834848

  12. Oxidative stress and its effects during dehydration.

    PubMed

    França, M B; Panek, A D; Eleutherio, E C A

    2007-04-01

    Water is usually thought to be required for the living state, but several organisms are capable of surviving complete dehydration (anhydrobiotes). Elucidation of the mechanisms of tolerance against dehydration may lead to development of new methods for preserving biological materials that do not normally support drying, which is of enormous practical importance in industry, in clinical medicine as well as in agriculture. One of the molecular mechanisms of damage leading to death in desiccation-sensitive cells upon drying is free-radical attack to phospholipids, DNA and proteins. This review aims to summarize the strategies used by anhydrobiotes to cope with the danger of oxygen toxicity and to present our recent results about the importance of some antioxidant defense systems in the dehydration tolerance of Saccharomyces cerevisiae, a usual model in the study of stress response.

  13. Oxidative stress in the cochlea: an update.

    PubMed

    Poirrier, A L; Pincemail, J; Van Den Ackerveken, P; Lefebvre, P P; Malgrange, B

    2010-01-01

    This paper will focus on understanding the role and action of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the molecular and biochemical pathways responsible for the regulation of the survival of hair cells and spiral ganglion neurons in the auditory portion of the inner ear. The pivotal role of ROS/RNS in ototoxicity makes them potentially valuable candidates for effective otoprotective strategies. In this review, we describe the major characteristics of ROS/RNS and the different oxidative processes observed during ototoxic cascades. At each step, we discuss their potential as therapeutic targets because an increasing number of compounds that modulate ROS/RNS processing or targets are being identified.

  14. The Oxygen Paradox, Oxidative Stress, and Ageing

    PubMed Central

    Davies, Kelvin J. A.

    2015-01-01

    Professor Helmut Sies is being lauded in this special issue of Archives of Biochemistry & Biophysics, on the occasion of his retirement as Editor-in-Chief. There is no doubt that Helmut has exerted an enormously positive influence on this journal, the fields of Biochemistry & Biophysics in general, and the areas of free radical and redox biology & medicine in particular. Helmut Sies' many discoveries about peroxide metabolism, glutathione, glutathione peroxidases, singlet oxygen, carotenoids in general and lycopene in particular, and flavonoids, fill the pages of his more than 600 publications. In addition, he will forever be remembered for coining the term ‘oxidative stress’ that is so widely used (and sometimes abused) by most of his colleagues. PMID:27095211

  15. The effects of anesthetic agents on oxidative stress

    NASA Astrophysics Data System (ADS)

    Yakan, Selvinaz; Düzgüner, Vesile

    2016-04-01

    Oxidative stress can be defined as the instability between antioxidant defense of the body and the production of free radical that causes peroxydation on the lipid layer. Free radicals are reactive oxygen species that are produced in the course of normal metabolisms of aerobe organisms and they may cause disorders in cell structure and organelles by interacting macromolecules, like lipid, protein, nucleic acids. Therefore, they may cause cardiovascular, immune system, liver, kidney illnesses and many other illnesses like cancer, aging, cataract, diabetes. It is known that many drugs used for the purpose of anesthetizing may cause lipid peroxidation in organism. For these reasons, determining the Oxidative stress index of anaesthetic stress chosen in the ones that are exposed to long term anaesthetic agents and anaesthesia appliccations, is so substantial.

  16. Non-thermal Plasma and Oxidative Stress

    NASA Astrophysics Data System (ADS)

    Toyokuni, Shinya

    2015-09-01

    Thermal plasmas and lasers have been used in medicine to cut and ablate tissues and for coagulation. Non-equilibrium atmospheric pressure plasma (NEAPP; non-thermal plasma) is a recently developed, non-thermal technique with possible biomedical applications. Although NEAPP reportedly generates reactive oxygen/nitrogen species, electrons, positive ions, and ultraviolet radiation, few research projects have been conducted to merge this technique with conventional free radical biology. Recently, Prof. Masaru Hori's group (Plasma Nanotechnology Research Center, Nagoya University) developed a NEAPP device with high electron density. Here electron spin resonance revealed hydroxyl radicals as a major product. To merge non-thermal plasma biology with the preexisting free radical biology, we evaluated lipid peroxidation and DNA modifications in various in vitro and ex vivo experiments. Conjugated dienes increased after exposure to linoleic and alfa-linolenic acids. An increase in 2-thiobarbituric acid-reactive substances was also increased after exposure to phosphatidylcholine, liposomes or liver homogenate. Direct exposure to rat liver in medium produced immunohistochemical evidence of 4-hydroxy-2-nonenal- and acrolein-modified proteins. Exposure to plasmid DNA induced dose-dependent single/double strand breaks and increased the amounts of 8-hydroxy-2'-deoxyguanosine and cyclobutane pyrimidine dimers. These results indicate that oxidative biomolecular damage by NEAPP is dose-dependent and thus can be controlled in a site-specific manner. Simultaneous oxidative and UV-specific DNA damage may be useful in cancer treatment. Other recent advancements in the related studies of non-thermal plasma in Nagoya University Graduate School of Medicine will also be discussed.

  17. Oxidative stress and DNA methylation regulation in the metabolic syndrome.

    PubMed

    Yara, Sabrina; Lavoie, Jean-Claude; Levy, Emile

    2015-01-01

    DNA methylation is implicated in tissue-specific gene expression and genomic imprinting. It is modulated by environmental factors, especially nutrition. Modified DNA methylation patterns may contribute to health problems and susceptibility to complex diseases. Current advances have suggested that the metabolic syndrome (MS) is a programmable disease, which is characterized by epigenetic modifications of vital genes when exposed to oxidative stress. Therefore, the main objective of this paper is to critically review the central context of MS while presenting the most recent knowledge related to epigenetic alterations that are promoted by oxidative stress. Potential pro-oxidant mechanisms that orchestrate changes in methylation profiling and are related to obesity, diabetes and hypertension are discussed. It is anticipated that the identification and understanding of the role of DNA methylation marks could be used to uncover early predictors and define drugs or diet-related treatments able to delay or reverse epigenetic changes, thereby combating MS burden.

  18. Diabetes and Kidney Disease: Role of Oxidative Stress

    PubMed Central

    Jha, Jay C.; Banal, Claudine; Chow, Bryna S.M.; Cooper, Mark E.

    2016-01-01

    Abstract Significance: Intrarenal oxidative stress plays a critical role in the initiation and progression of diabetic kidney disease (DKD). Enhanced oxidative stress results from overproduction of reactive oxygen species (ROS) in the context of concomitant, insufficient antioxidant pathways. Renal ROS production in diabetes is predominantly mediated by various NADPH oxidases (NOXs), but a defective antioxidant system as well as mitochondrial dysfunction may also contribute. Recent Advances: Effective agents targeting the source of ROS generation hold the promise to rescue the kidney from oxidative damage and prevent subsequent progression of DKD. Critical Issues and Future Directions: In the present review, we summarize and critically analyze molecular and cellular mechanisms that have been demonstrated to be involved in NOX-induced renal injury in diabetes, with particular focus on the role of increased glomerular injury, the development of albuminuria, and tubulointerstitial fibrosis, as well as mitochondrial dysfunction. Furthermore, novel agents targeting NOX isoforms are discussed. Antioxid. Redox Signal. 25, 657–684. PMID:26906673

  19. Oxidative stress response and Nrf2 signaling in aging

    PubMed Central

    Zhang, Hongqiao; Davies, Kelvin J. A.; Forman, Henry Jay

    2015-01-01

    Increasing oxidative stress, a major characteristic of aging, has been implicated in variety of age-related pathologies. In aging, oxidant production from several sources is increased while antioxidant enzymes, the primary lines of defense, are decreased. Repair systems, including the proteasomal degradation of damaged proteins also declines. Importantly, the adaptive response to oxidative stress declines with aging. Nrf2/EpRE signaling regulates the basal and inducible expression of many antioxidant enzymes and the proteasome. Nrf2/EpRE activity is regulated at several levels including transcription, post-translation, and interaction with other proteins. This review summarizes current studies on age-related impairment of Nrf2/EpRE function and discusses the change of Nrf2 regulatory mechanisms with aging. PMID:26066302

  20. Marine Carotenoids against Oxidative Stress: Effects on Human Health.

    PubMed

    Gammone, Maria Alessandra; Riccioni, Graziano; D'Orazio, Nicolantonio

    2015-09-30

    Carotenoids are lipid-soluble pigments that are produced in some plants, algae, fungi, and bacterial species, which accounts for their orange and yellow hues. Carotenoids are powerful antioxidants thanks to their ability to quench singlet oxygen, to be oxidized, to be isomerized, and to scavenge free radicals, which plays a crucial role in the etiology of several diseases. Unusual marine environments are associated with a great chemical diversity, resulting in novel bioactive molecules. Thus, marine organisms may represent an important source of novel biologically active substances for the development of therapeutics. In this respect, various novel marine carotenoids have recently been isolated from marine organisms and displayed several utilizations as nutraceuticals and pharmaceuticals. Marine carotenoids (astaxanthin, fucoxanthin, β-carotene, lutein but also the rare siphonaxanthin, sioxanthin, and myxol) have recently shown antioxidant properties in reducing oxidative stress markers. This review aims to describe the role of marine carotenoids against oxidative stress and their potential applications in preventing and treating inflammatory diseases.

  1. Deubiquitinases as a signaling target of oxidative stress

    PubMed Central

    Cotto-Rios, Xiomaris M.; Békés, Miklos; Chapman, Jessica; Ueberheide, Beatrix; Huang, Tony T.

    2012-01-01

    SUMMARY Deubiquitinating enzymes (DUBs) constitute a large family of cysteine proteases that have broad impact on numerous biological and pathological processes, including the regulation of genomic stability. DUBs are often assembled onto multiprotein complexes to assist in their localization and substrate selection, yet it remains unclear how the enzymatic activity of DUBs is modulated by intracellular signals. Herein, we show that bursts of reactive oxygen species (ROS) reversibly inactivate DUBs through the oxidation of the catalytic cysteine residue. Importantly, USP1, a key regulator of genomic stability, is reversibly inactivated upon oxidative stress. This, in part, explains the rapid nature of PCNA monoubiquitination-dependent DNA damage tolerance in response to oxidative DNA damage in replicating cells. We propose that DUBs of the cysteine protease family act as ROS sensors in human cells and that ROS-mediated DUB inactivation is a critical mechanism for fine-tuning stress-activated signaling pathways. PMID:23219552

  2. Role of oxidative stress in transformation induced by metal mixture.

    PubMed

    Martín, Silva-Aguilar; Emilio, Rojas; Mahara, Valverde

    2011-01-01

    Metals are ubiquitous pollutants present as mixtures. In particular, mixture of arsenic-cadmium-lead is among the leading toxic agents detected in the environment. These metals have carcinogenic and cell-transforming potential. In this study, we used a two step cell transformation model, to determine the role of oxidative stress in transformation induced by a mixture of arsenic-cadmium-lead. Oxidative damage and antioxidant response were determined. Metal mixture treatment induces the increase of damage markers and the antioxidant response. Loss of cell viability and increased transforming potential were observed during the promotion phase. This finding correlated significantly with generation of reactive oxygen species. Cotreatment with N-acetyl-cysteine induces effect on the transforming capacity; while a diminution was found in initiation, in promotion phase a total block of the transforming capacity was observed. Our results suggest that oxidative stress generated by metal mixture plays an important role only in promotion phase promoting transforming capacity.

  3. [Effect of mexicor on oxidative stress in acute myocardial infarction].

    PubMed

    Golikov, A P; Davydov, B V; Rudnev, D V; Klychnikova, E V; Bykova, N S; Riabinin, V A; Polumiskov, V Iu; Nikolaeva, N Iu; Golikov, P P

    2005-01-01

    Mexicor (5% solution and capsules) was used in 40 of 80 conventionally treated patients with acute myocardial infarction. The drug was given intravenously for 5 days, than intramuscularly (6-9 mg/kg) for 9 days and orally (0.1 mg t.i.d.) thereafter until discharge. Severity of oxidative stress was evaluated by K coefficient. Calculation of this coefficient required data on degree of oxidation of lipids in blood serum, serum levels of diene conjugates, malonic dialdehyde, alpha-tocopherol and ceruloplasmin. These parameters as well as activity of superoxide dismutase, glutathione peroxidase and catalase in erythrocytes were measured at admission, on days 2, 3, 7, 14 and at discharge. Mexicor treated compared with untreated (n=40) patients were characterized by diminished severity of oxidative stress at the account of lower levels of lipid peroxidation products and augmented compensatory potential of the endogenous antioxidant system.

  4. Hepatitis B and its Relationship With Oxidative Stress

    PubMed Central

    Alavian, Seyed Moayed; Showraki, Alireza

    2016-01-01

    Context Despite the great breakthroughs we have witnessed in the last 50 years in the prevention, diagnosis, and treatment of hepatitis B, we are still far from eradicating or even curing the disease. Achieving further progress in controlling this disease will not be possible without discovering the exact pathogenesis behind it. One prime suspect in the pathogenesis of various diseases is oxidative stress. This review will exclusively explore hepatitis B in the context of oxidative stress to obtain a more comprehensive clinical perspective on its pathogenesis and eventual medical therapy. Evidence Acquisition We systematically searched PubMed, Google Scholar, Web of Science, EMBASE, and Scopus using an extensive list of keywords in the following three categories: 1) Hepatitis B and oxidation 2) Hepatitis B and antioxidant system 3) Effects of approved anti-hepatitis B drugs on redox status. All relevant articles were obtained and reviewed carefully after the exclusion criteria were deployed. Results There is great evidence indicating extensive oxidative stress occurs in hepatitis B. This oxidative stress takes place on multiple levels, including lipid peroxidation, DNA oxidation, protein oxidation, and reactive oxygen and nitrogen species production. However, there are also conflicting results with regard to antioxidant therapy and antioxidant status in hepatitis B, some of which may be explained by the concept of “compensatory gaps.” Nevertheless, further studies are indicated to reach a more thorough judgment. Conclusions Despite the presence of vast oxidative stress in hepatitis B, antioxidant therapy is not always effective as a treatment strategy, especially considering that antioxidants can act as “double-edged swords” or antioxidants; if not used at the right time or place or in the right combination, these substances can easily become pro-oxidants. Therefore, several studies will be needed to determine suitable antioxidant therapies. We propose the

  5. N-acetylcysteine attenuates dimethylnitrosamine induced oxidative stress in rats.

    PubMed

    Sathish, Priya; Paramasivan, Vijayalakshmi; Palani, Vivekanandan; Sivanesan, Karthikeyan

    2011-03-05

    Oxidative stress has been implicated in the pathogenesis and progression of various hepatic disorders and hence screening for a good hepatoprotective and antioxidant agent is the need of the hour. The present study was aimed to investigate the hepatoprotective and antioxidant property of N-acetylcysteine (NAC) against dimethylnitrosamine (DMN) induced oxidative stress and hepatocellular damage in male Wistar albino rats. Administration of single dose of DMN (5mg/kg b.w.; i.p.) resulted in significant elevation in the levels of serum aspartate transaminase and alanine transaminase, indicating hepatocellular damage. Oxidative stress induced by DMN treatment was confirmed by an elevation in the status of lipid peroxidation (LPO) and reduction in the activities of enzymic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase and in the levels of non-enzymic antioxidants, reduced glutathione, vitamin-C and vitamin-E in the liver tissue. DMN induced oxidative stress and hepatocellular membrane instability was further substantiated by a decline in the status of the membrane bound ATPases in the liver tissue. Post-treatment with NAC (50mg/kg b.w.; p.o.) for 7days effectively protected against the DMN induced insult to liver by preventing the elevation in the status of the serum marker enzymes and LPO, and restoring the activities of both the enzymic and non-enzymic antioxidants and membrane bound ATPases towards normalcy. These results demonstrate that NAC acts as a good hepatoprotective and antioxidant agent in attenuating DMN induced oxidative stress and hepatocellular damage.

  6. Exercise-induced oxidative stress and hypoxic exercise recovery.

    PubMed

    Ballmann, Christopher; McGinnis, Graham; Peters, Bridget; Slivka, Dustin; Cuddy, John; Hailes, Walter; Dumke, Charles; Ruby, Brent; Quindry, John

    2014-04-01

    Hypoxia due to altitude diminishes performance and alters exercise oxidative stress responses. While oxidative stress and exercise are well studied, the independent impact of hypoxia on exercise recovery remains unknown. Accordingly, we investigated hypoxic recovery effects on post-exercise oxidative stress. Physically active males (n = 12) performed normoxic cycle ergometer exercise consisting of ten high:low intensity intervals, 20 min at moderate intensity, and 6 h recovery at 975 m (normoxic) or simulated 5,000 m (hypoxic chamber) in a randomized counter-balanced cross-over design. Oxygen saturation was monitored via finger pulse oximetry. Blood plasma obtained pre- (Pre), post- (Post), 2 h post- (2Hr), 4 h post- (4Hr), and 6 h (6Hr) post-exercise was assayed for Ferric Reducing Ability of Plasma (FRAP), Trolox Equivalent Antioxidant Capacity (TEAC), Lipid Hydroperoxides (LOOH), and Protein Carbonyls (PC). Biopsies from the vastus lateralis obtained Pre and 6Hr were analyzed by real-time PCR quantify expression of Heme oxygenase 1 (HMOX1), Superoxide Dismutase 2 (SOD2), and Nuclear factor (euthyroid-derived2)-like factor (NFE2L2). PCs were not altered between trials, but a time effect (13 % Post-2Hr increase, p = 0.044) indicated exercise-induced blood oxidative stress. Plasma LOOH revealed only a time effect (p = 0.041), including a 120 % Post-4Hr increase. TEAC values were elevated in normoxic recovery versus hypoxic recovery. FRAP values were higher 6Hr (p = 0.045) in normoxic versus hypoxic recovery. Exercise elevated gene expression of NFE2L2 (20 % increase, p = 0.001) and SOD2 (42 % increase, p = 0.003), but hypoxic recovery abolished this response. Data indicate that recovery in a hypoxic environment, independent of exercise, may alter exercise adaptations to oxidative stress and metabolism.

  7. Graded hypoxia and blood oxidative stress during exercise recovery.

    PubMed

    Peters, Bridget; Ballmann, Christopher; Mcginnis, Graham; Epstein, Erin; Hyatt, Hayden; Slivka, Dustin; Cuddy, John; Hailes, William; Dumke, Charles; Ruby, Brent; Quindry, John

    2016-01-01

    Altitude exposure and exercise elicit oxidative stress in blood; however, exercise recovery at 5000 m attenuates oxidative stress. The purpose was to determine the altitude threshold at which blood oxidative stress is blunted during exercise recovery. Twelve males 18-28 years performed four-cycle ergometry bouts (60 min, 70% VO2max, at 975 m). In a randomised counterbalanced crossover design, participants recovered 6 h at 0, 1667, 3333 and 5000 m in a normobaric hypoxia chamber (recovery altitudes were simulated by using a computerised system in an environmental chamber by lowering the partial pressure of oxygen to match that of the respective altitude). Oxygen saturation was monitored throughout exercise recovery. Blood samples obtained pre-, post-, 1 h post- and 5 h post-exercise were assayed for ferric-reducing antioxidant plasma, Trolox equivalent antioxidant capacity, uric acid, lipid hydroperoxides and protein carbonyls. Muscle biopsies obtained pre and 6 h were analysed by real-time polymerase chain reaction to quantify expression of hemeoxgenase 1, superoxide dismutase 2 and nuclear factor (euthyroid-derived 2)-like factor. Pulse oximetry data were similar during exercise, but decreased for the three highest recovery elevations (0 m = 0%, 1667 m = -3%; 3333 m = -7%; 5000 m = -17%). A time-dependent oxidative stress occurred following exercise for all variables, but the two highest recovery altitudes partially attenuated the lipid hydroperoxide response (0 m = +135%, 1667 m = +251%, 3333 m = +99%; 5000 m = +108%). Data may indicate an altitude threshold between 1667 and 3333 m, above which the oxidative stress response is blunted during exercise recovery.

  8. Myocardial Oxidative Stress in Infants Undergoing Cardiac Surgery.

    PubMed

    Sznycer-Taub, Nathaniel; Mackie, Stewart; Peng, Yun-Wen; Donohue, Janet; Yu, Sunkyung; Aiyagari, Ranjit; Charpie, John

    2016-04-01

    Cardiac surgery for congenital heart disease often necessitates a period of myocardial ischemia during cardiopulmonary bypass and cardioplegic arrest, followed by reperfusion after aortic cross-clamp removal. In experimental models, myocardial ischemia-reperfusion is associated with significant oxidative stress and ventricular dysfunction. A prospective observational study was conducted in infants (<1 year) who underwent elective surgical repair of a ventricular septal defect (VSD) or tetralogy of Fallot (TOF). Blood samples were drawn following anesthetic induction (baseline) and directly from the coronary sinus at 1, 3, 5, and 10 min following aortic cross-clamp removal. Samples were analyzed for oxidant stress using assays for thiobarbituric acid-reactive substances, protein carbonyl, 8-isoprostane, and total antioxidant capacity. For each subject, raw assay data were normalized to individual baseline samples and expressed as fold-change from baseline. Results were compared using a one-sample t test with Bonferroni correction for multiple comparisons. Sixteen patients (ten with TOF and six with VSD) were enrolled in the study, and there were no major postoperative complications observed. For the entire cohort, there was an immediate, rapid increase in myocardial oxidative stress that was sustained for 10 min following aortic cross-clamp removal in all biomarker assays (all P < 0.01), except total antioxidant capacity. Infant cardiac surgery is associated with a rapid, robust, and time-dependent increase in myocardial oxidant stress as measured from the coronary sinus in vivo. Future studies with larger enrollment are necessary to assess any association between myocardial oxidative stress and early postoperative outcomes.

  9. Linking phosphorus availability with photo-oxidative stress in plants.

    PubMed

    Hernández, Iker; Munné-Bosch, Sergi

    2015-05-01

    Plants have evolved a plethora of mechanisms to circumvent the potential damaging effects of living under low phosphorus availability in the soil. These mechanisms include different levels of organization, from root-shoot signalling at the whole-plant level to specific biochemical responses at the subcellular level, such as reductions in photosynthesis and the consequent activation of photo- and antioxidant mechanisms in chloroplasts. Some recent studies clearly indicate that severe phosphorus deficiency can lead to alterations in the photosynthetic apparatus, including reductions in CO2 assimilation rates, a down-regulation of photosynthesis-related genes and photoinhibition at the photosystem II level, thus causing potential photo-oxidative stress. Photo-oxidative stress is characterized by an increased production of reactive oxygen species in chloroplasts, which at low concentrations can serve a signalling, protective role, but when present at high concentrations can cause damage to lipids, proteins and nucleic acids, thus leading to irreversible injuries. We discuss here the mechanisms that phosphate-starved plants have evolved to withstand photo-oxidative stress, including changes at the subcellular level (e.g. activation of photo- and antioxidant protection mechanisms in chloroplasts), cellular and tissular levels (e.g. activation of photorespiration and anthocyanin accumulation) and whole-plant level (alterations in source-sink relationships modulated by hormones). Of particular importance is the current evidence demonstrating that phosphate-starved plants activate simultaneous responses at multiple levels, from transcriptional changes to root-shoot signalling, to prevent oxidative damage. In this review, we summarize current knowledge about the occurrence of photo-oxidative stress in phosphate-starved plants and highlight the mechanisms these plants have evolved to prevent oxidative damage under phosphorus limitation at the subcellular, cellular and whole

  10. Liver Metabolomics Reveals Increased Oxidative Stress and Fibrogenic Potential in Gfrp Transgenic Mice in Response to Ionizing Radiation

    PubMed Central

    2015-01-01

    Although radiation-induced tissue-specific injury is well documented, the underlying molecular changes resulting in organ dysfunction and the consequences thereof on overall metabolism and physiology have not been elucidated. We previously reported the generation and characterization of a transgenic mouse strain that ubiquitously overexpresses Gfrp (GTPH-1 feedback regulatory protein) and exhibits higher oxidative stress, which is a possible result of decreased tetrahydrobiopterin (BH4) bioavailability. In this study, we report genotype-dependent changes in the metabolic profiles of liver tissue after exposure to nonlethal doses of ionizing radiation. Using a combination of untargeted and targeted quantitative mass spectrometry, we report significant accumulation of metabolites associated with oxidative stress, as well as the dysregulation of lipid metabolism in transgenic mice after radiation exposure. The radiation stress seems to exacerbate lipid peroxidation and also results in higher expression of genes that facilitate liver fibrosis, in a manner that is dependent on the genetic background and post-irradiation time interval. These findings suggest the significance of Gfrp in regulating redox homeostasis in response to stress induced by ionizing radiation affecting overall physiology. PMID:24824572

  11. Liver metabolomics reveals increased oxidative stress and fibrogenic potential in gfrp transgenic mice in response to ionizing radiation.

    PubMed

    Cheema, Amrita K; Pathak, Rupak; Zandkarimi, Fereshteh; Kaur, Prabhjit; Alkhalil, Lynn; Singh, Rajbir; Zhong, Xiaogang; Ghosh, Sanchita; Aykin-Burns, Nukhet; Hauer-Jensen, Martin

    2014-06-06

    Although radiation-induced tissue-specific injury is well documented, the underlying molecular changes resulting in organ dysfunction and the consequences thereof on overall metabolism and physiology have not been elucidated. We previously reported the generation and characterization of a transgenic mouse strain that ubiquitously overexpresses Gfrp (GTPH-1 feedback regulatory protein) and exhibits higher oxidative stress, which is a possible result of decreased tetrahydrobiopterin (BH4) bioavailability. In this study, we report genotype-dependent changes in the metabolic profiles of liver tissue after exposure to nonlethal doses of ionizing radiation. Using a combination of untargeted and targeted quantitative mass spectrometry, we report significant accumulation of metabolites associated with oxidative stress, as well as the dysregulation of lipid metabolism in transgenic mice after radiation exposure. The radiation stress seems to exacerbate lipid peroxidation and also results in higher expression of genes that facilitate liver fibrosis, in a manner that is dependent on the genetic background and post-irradiation time interval. These findings suggest the significance of Gfrp in regulating redox homeostasis in response to stress induced by ionizing radiation affecting overall physiology.

  12. Acute exacerbation of COPD.

    PubMed

    Ko, Fanny W; Chan, Ka Pang; Hui, David S; Goddard, John R; Shaw, Janet G; Reid, David W; Yang, Ian A

    2016-10-01

    The literature of acute exacerbation of chronic obstructive pulmonary disease (COPD) is fast expanding. This review focuses on several aspects of acute exacerbation of COPD (AECOPD) including epidemiology, diagnosis and management. COPD poses a major health and economic burden in the Asia-Pacific region, as it does worldwide. Triggering factors of AECOPD include infectious (bacteria and viruses) and environmental (air pollution and meteorological effect) factors. Disruption in the dynamic balance between the 'pathogens' (viral and bacterial) and the normal bacterial communities that constitute the lung microbiome likely contributes to the risk of exacerbations. The diagnostic approach to AECOPD varies based on the clinical setting and severity of the exacerbation. After history and examination, a number of investigations may be useful, including oximetry, sputum culture, chest X-ray and blood tests for inflammatory markers. Arterial blood gases should be considered in severe exacerbations, to characterize respiratory failure. Depending on the severity, the acute management of AECOPD involves use of bronchodilators, steroids, antibiotics, oxygen and noninvasive ventilation. Hospitalization may be required, for severe exacerbations. Nonpharmacological interventions including disease-specific self-management, pulmonary rehabilitation, early medical follow-up, home visits by respiratory health workers, integrated programmes and telehealth-assisted hospital at home have been studied during hospitalization and shortly after discharge in patients who have had a recent AECOPD. Pharmacological approaches to reducing risk of future exacerbations include long-acting bronchodilators, inhaled steroids, mucolytics, vaccinations and long-term macrolides. Further studies are needed to assess the cost-effectiveness of these interventions in preventing COPD exacerbations.

  13. Psychological stress during exercise: immunoendocrine and oxidative responses.

    PubMed

    Huang, Chun-Jung; Webb, Heather E; Evans, Ronald K; McCleod, Kelly A; Tangsilsat, Supatchara E; Kamimori, Gary H; Acevedo, Edmund O

    2010-12-01

    The purpose of this study was to examine the changes in catecholamines (epinephrine [EPI] and norepinephrine [NE]), interleukin-2 (IL-2) and a biomarker of oxidative stress (8-isoprostane) in healthy individuals who were exposed to a dual challenge (physical and psychological stress). Furthermore, this study also examined the possible relationships between catecholamines (NE and EPI) and 8-isoprostane and between IL-2 and 8-isoprostane following a combined physical and psychological challenge. Seven healthy male subjects completed two experimental conditions. The exercise-alone condition (EAC) consisted of cycling at 60% VO(2max) for 37 min, while the dual-stress condition (DSC) included 20 min of a mental challenge while cycling. DSC showed greater EPI and 8-isoprostane levels (significant condition by time interaction). NE and IL-2 revealed significant change across time in both conditions. In addition, following dual stress, EPI area-under-the-curve (AUC) demonstrated a positive correlation with NE AUC and IL-2 AUC. NE AUC was positively correlated with IL-2 AUC and peak 8-isoprostane, and peak IL-2 was positively correlated with peak 8-isoprostane in response to a dual stress. The potential explanation for elevated oxidative stress during dual stress may be through the effects of the release of catecholamines and IL-2. These findings may further provide the potential explanation that dual stress alters physiological homeostasis in many occupations including firefighting, military operations and law enforcement. A greater understanding of these responses to stress can assist in finding strategies (e.g. exercise training) to overcome the inherent psychobiological challenges associated with physically and mentally demanding professions.

  14. High Sodium-Induced Oxidative Stress and Poor Anticrystallization Defense Aggravate Calcium Oxalate Crystal Formation in Rat Hyperoxaluric Kidneys.

    PubMed

    Huang, Ho-Shiang; Ma, Ming-Chieh

    2015-01-01

    Enhanced sodium excretion is associated with intrarenal oxidative stress. The present study evaluated whether oxidative stress caused by high sodium (HS) may be involved in calcium oxalate crystal formation. Male rats were fed a sodium-depleted diet. Normal-sodium and HS diets were achieved by providing drinking water containing 0.3% and 3% NaCl, respectively. Rats were fed a sodium-depleted diet with 5% hydroxyl-L-proline (HP) for 7 and 42 days to induce hyperoxaluria and/or calcium oxalate deposition. Compared to normal sodium, HS slightly increased calcium excretion despite diuresis; however, the result did not reach statistical significance. HS did not affect the hyperoxaluria, hypocalciuria or supersaturation caused by HP; however, it increased calcium oxalate crystal deposition soon after 7 days of co-treatment. Massive calcium oxalate formation and calcium crystal excretion in HS+HP rats were seen after 42 days of treatment. HP-mediated hypocitraturia was further exacerbated by HS. Moreover, HS aggravated HP-induced renal injury and tubular damage via increased apoptosis and oxidative stress. Increased urinary malondialdehyde excretion, in situ superoxide production, NAD(P)H oxidase and xanthine oxidase expression and activity, and decreased antioxidant enzyme expression or activity in the HS+HP kidney indicated exaggerated oxidative stress. Interestingly, this redox imbalance was associated with reduced renal osteopontin and Tamm-Horsfall protein expression (via increased excretion) and sodium-dependent dicarboxylate cotransporter NaDC-1 upregulation. Collectively, our results demonstrate that a HS diet induces massive crystal formation in the hyperoxaluric kidney; this is not due to increased urinary calcium excretion but is related to oxidative injury and loss of anticrystallization defense.

  15. Visualization of Oxidative Stress Induced by Experimental Periodontitis in Keap1-Dependent Oxidative Stress Detector-Luciferase Mice

    PubMed Central

    Kataoka, Kota; Ekuni, Daisuke; Tomofuji, Takaaki; Irie, Koichiro; Kunitomo, Muneyoshi; Uchida, Yoko; Fukuhara, Daiki; Morita, Manabu

    2016-01-01

    The aim of this study was to investigate whether a Keap1-dependent oxidative stress detector-luciferase (OKD-LUC) mouse model would be useful for the visualization of oxidative stress induced by experimental periodontitis. A ligature was placed around the mandibular first molars for seven days to induce periodontitis. Luciferase activity was measured with an intraperitoneal injection of d-luciferin on days 0, 1, and 7. The luciferase activity in the periodontitis group was significantly greater than that in the control group at seven days. The expressions of heme oxygenase-1 (HO-1) and malondialdehyde in periodontal tissue were significantly higher in the periodontitis group than in the control group. Immunofluorescent analysis confirmed that the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) occurred more frequently in the periodontitis group than in the control group. This study found that under oxidative stress induced by experimental periodontitis, the Nrf2/antioxidant defense pathway was activated and could be visualized from the luciferase activity in the OKD-LUC model. Thus, the OKD-LUC mouse model may be useful for exploring the mechanism underlying the relationship between the Nrf2/antioxidant defense pathway and periodontitis by enabling the visualization of oxidative stress over time. PMID:27854327

  16. Acetaminophen protects brain endothelial cells against oxidative stress.

    PubMed

    Tripathy, Debjani; Grammas, Paula

    2009-05-01

    Increasing evidence suggests that acetaminophen has unappreciated anti-oxidant and anti-inflammatory properties. Drugs that affect oxidant and inflammatory stress in the brain are of interest because both processes are thought to contribute to the pathogenesis of neurodegenerative disease. The objective of this study is to determine whether acetaminophen affects the response of brain endothelial cells to oxidative stress. Cultured brain endothelial cells are pre-treated with acetaminophen and then exposed to the superoxide-generating compound menadione (25 microM). Cell survival, inflammatory protein expression, and anti-oxidant enzyme activity are measured. Menadione causes a significant (p<0.001) increase in endothelial cell death as well as an increase in RNA and protein levels of tumor necrosis factor alpha, interleukin-1, macrophage inflammatory protein alpha, and RANTES. Menadione also evokes a significant (p<0.001) increase in the activity of the anti-oxidant enzyme superoxide dismutase (SOD). Pre-treatment of endothelial cell cultures with acetaminophen (25-100 microM) increases endothelial cell survival and inhibits menadione-induced expression of inflammatory proteins and SOD activity. In addition, we document, for the first time, that acetaminophen increases expression of the anti-apoptotic protein Bcl2. Suppressing Bcl2 with siRNA blocks the pro-survival effect of acetaminophen. These data show that acetaminophen has anti-oxidant and anti-inflammatory effects on the cerebrovasculature and suggest a heretofore unappreciated therapeutic potential for this drug in neurodegenerative diseases such as Alzheimer's disease that are characterized by oxidant and inflammatory stress.

  17. [Indices of oxidative stress. 2. Lipid peroxides].

    PubMed

    Lushchak, V I; Bahniukova, T V; Luzhna, L I

    2006-01-01

    Two methods of the determination of lipid peroxidation products have been compared which are based on Fe(II) oxidation by them at acid pH values in the presence of xylenol orange which binds Fe(III) have been compared. The first method uses cumene hydropeoxide as an internal standard. In the second one, lipid peroxides are previously reduced by triphenylphosphine and these substances content is measured as a difference of the production of complexes with xylenol orange and iron ions in the control (with reduction) and experimental sample (without reduction). The optimization of measurement conditions is described. The levels of lipid peroxides in goldfish tissues assayed simultaneously by two methods were similar. The method with cumene hydroperoxide needs less amounts of biological material; moreover, there is no necessity in a calibration curve. Effects of hyperoxia on lipid peroxide levels in goldfish tissues were studied with the cumene method. Within the first hours of hyperoxia this index increased 13-times in the liver and 2-times in the brain and muscle. The further exposure rebounded this parameter to the initial level. Levels of lipid peroxides positively correlated with levels of end products of lipid peroxidation (thiobarbiturate acid reactive substances) in the goldfish tissues. The method of quantification of lipid peroxides with cumene is recommended for wide using in biological investigations.

  18. Nitric oxide ameliorates the damaging effects of oxidative stress induced by iron deficiency in cyanobacterium Anabaena 7120.

    PubMed

    Kaushik, Manish Singh; Srivastava, Meenakshi; Srivastava, Alka; Singh, Anumeha; Mishra, Arun Kumar

    2016-11-01

    In cyanobacterium Anabaena 7120, iron deficiency leads to oxidative stress with unavoidable consequences. Nitric oxide reduces pigment damage and supported the growth of Anabaena 7120 in iron-deficient conditions. Elevation in nitric oxide accumulation and reduced superoxide radical production justified the role of nitric oxide in alleviating oxidative stress in iron deficiency. Increased activities of antioxidative enzymes and higher levels of ROS scavengers (ascorbate, glutathione and thiol) in iron deficiency were also observed in the presence of nitric oxide. Nitric oxide also supported the membrane integrity of Anabaena cells and reduces protein and DNA damage caused by oxidative stress induced by iron deficiency. Results suggested that nitric oxide alleviates the damaging effects of oxidative stress induced by iron deficiency in cyanobacterium Anabaena 7120.

  19. l-Arginine Enhances Resistance against Oxidative Stress and Heat Stress in Caenorhabditis elegans

    PubMed Central

    Ma, Heran; Ma, Yudan; Zhang, Zhixian; Zhao, Ziyuan; Lin, Ran; Zhu, Jinming; Guo, Yi; Xu, Li

    2016-01-01

    The antioxidant properties of l-arginine (l-Arg) in vivo, and its effect on enhancing resistance to oxidative stress and heat stress in Caenorhabditis elegans were investigated. C. elegans, a worm model popularly used in molecular and developmental biology, was used in the present study. Here, we report that l-Arg, at a concentration of 1 mM, prolonged C. elegans life by 26.98% and 37.02% under oxidative and heat stress, respectively. Further experiments indicated that the longevity-extending effects of l-Arg may be exerted by its free radical scavenging capacity and the upregulation of aging-associated gene expression in worms. This work is important in the context of numerous recent studies that concluded that environment stresses are associated with an increased population death rate. PMID:27690079

  20. Nitric oxide during ischemia attenuates oxidant stress and cell death during ischemia and reperfusion in cardiomyocytes.

    PubMed

    Iwase, Hirotaro; Robin, Emmanuel; Guzy, Robert D; Mungai, Paul T; Vanden Hoek, Terry L; Chandel, Navdeep S; Levraut, Jacques; Schumacker, Paul T

    2007-08-15

    Nitric oxide (NO) has been implicated as a cardioprotective agent during ischemia/reperfusion (I/R), but the mechanism of protection is unknown. Oxidant stress contributes to cell death in I/R, so we tested whether NO protects by attenuating oxidant stress. Cardiomyocytes and murine embryonic fibroblasts were administered NO (10-1200 nM) during simulated ischemia, and cell death was assessed during reperfusion without NO. In each case, NO abrogated cell death during reperfusion. Cells overexpressing endothelial NO synthase (NOS) exhibited a similar protection, which was abolished by the NOS inhibitor N(omega)-nitro-l-arginine methyl ester. Protection was not mediated by guanylate cyclase or the mitochondrial K(ATP) channel, as inhibitors of these systems failed to abolish protection. NO did not prevent decreases in mitochondrial potential, but cells protected with NO demonstrated recovery of potential at reperfusion. Measurements using C11-BODIPY reveal that NO attenuates lipid peroxidation during ischemia and reperfusion. Measurements of oxidant stress using the ratiometric redox sensor HSP-FRET demonstrate that NO attenuates protein oxidation during ischemia. These findings reveal that physiological levels of NO during ischemia can attenuate oxidant stress both during ischemia and during reperfusion. This response is associated with a remarkable attenuation of cell death, suggesting that ischemic cell death may be a regulated event.