Potential sources of oxidative stress that induce postexercise proteinuria in rats

2008 ◽  
Vol 104 (4) ◽  
pp. 1063-1068 ◽  
Author(s):  
Günnur Koçer ◽  
Ümit Kemal Şentürk ◽  
Oktay Kuru ◽  
Filiz Gündüz

Exercise-induced proteinuria is a common consequence of physical activity and is caused predominantly by alterations in renal hemodynamics. Although it has been shown that exercise-induced oxidative stress can also contribute to the occurrence of postexercise proteinuria, the sources of reactive oxygen species that promote it are unknown. We investigated the enzymes nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and xanthine oxidase (XO) as possible sources of oxidative stress in postexercise proteinuria. First, we evaluated the effect of blocking the NADPH oxidase enzyme on postexercise proteinuria. We found a significant increase in urinary protein level, kidney thiobarbituric acid-reactive substances (TBARS), and protein carbonyl content after exhaustive exercise, and NADPH oxidase activity was induced by exercise. Rats that were treated with an NADPH oxidase inhibitor for 4 days before exhaustive exercise showed no increase in kidney TBARS or protein carbonyl derivative level and no proteinuria or NADPH oxidase activation. In the next set of experiments, we investigated the effect of XO blockage on postexercise proteinuria. Oxypurinol, an XO inhibitor was administered to rats for 3 days before exercise. Although XO inhibition significantly decreased kidney TBARS levels and protein carbonyl content in exercised rats, the inhibition did not prevent exercise-induced proteinuria. However, plasma and kidney XO activity was not induced by exercise, but rather it was suppressed under oxypurinol treatment. These results suggest that increased NADPH oxidase activity induced by exhaustive exercise is an important source of elevated oxidative, stress during exercise, which contributes to the occurrence of postexercise proteinuria.

2018 ◽  
Vol 4 (1) ◽  
pp. 170-181
Author(s):  
Darrell A. Jackson ◽  
Fanny Astruc-Diaz ◽  
Nicole M. Byrnes ◽  
Phillip H. Beske

Most 2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl) propanoic acid receptors (AMPARs) expressed on adult hippocampal pyramidal neurons contain the edited form of GluA2 (Q607R) and are thus impermeable to Ca2+/Zn2+ entry.  Following ischemic injury, these receptors undergo a subunit composition change, switching from a GluA2-containing Ca2+/Zn2+-impermeable AMPAR to a GluA2-lacking Ca2+/Zn2+-permeable AMPAR. Recent studies indicate that an oxidative stress signaling pathway is responsible for the I/R-induced changes in AMPAR subunit composition.  Studies suggest that nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase), a superoxide generator, is the source that initiates the oxidative stress-signaling cascade during post-ischemic reperfusion. The objective of the present study was to determine if suppression of NADPH oxidase activity prevents the increase in phosphorylation and subsequent internalization of the GluA2 AMPAR subunit during reperfusion of post-ischemic hippocampal slices. In this study, we demonstrated that exposure of adult rat hippocampal slices to oxygen glucose deprivation/reperfusion (OGD/R) results in an increase in Ser880 phosphorylation of the GluA2 subunit.  The increase in Ser880 phosphorylation resulted in the dissociation of GluA2 from the scaffolding proteins Glutamate receptor-interacting protein 1 (GRIP1) and AMPAR binding protein (ABP), thus enabling the association of GluA2 with protein interacting with C kinase 1 (PICK1). OGD/R also resulted in an increase in the association of activated protein kinase C ? (PKC?) with PICK1. We have found that pharmacological inhibition of NADPH oxidase with apocynin diminishes the OGD/R-induced increase in activated PKC? association with PICK1 and subsequent Ser880 phosphorylation of GluA2. Suppression of NADPH oxidase activity also blunted OGD/R-induced decreased association of GluA2 with the scaffolding proteins GRIP1 and ABP.  Protein phosphatase 2A (PP2A), which regulates PKC? activity by dephosphorylating the kinase, was inactivated by OGD/R-induced increase in tyrosine phosphorylation of the phosphatase (Y307). Inhibition of NADPH oxidase activity ameliorated OGD/R-induced PP2A phosphorylation and inactivation. Our findings are consistent with a model of OGD/R-induced Ser880 phosphorylation of GluA2 that implicates NADPH oxidase mediated inactivation of PP2A and sustained PKC? phosphorylation of GluA2.


2020 ◽  
Vol 70 (2) ◽  
pp. 227-237
Author(s):  
Eda Güneş

Abstract The aim of the this study was to evaluate the effects of fresh, dried and freeze-dried Centaurea depressa M. Bieb. (Asteraceae) on the oxidant and antioxidant status of the model organism D. melanogaster Meigen (Diptera: Drosophilidae) experimentally. The study was carried out from 2016 to 2019, and plant leaf extracts (0-50 mg/l) were added to insect standard artificial diets. The total protein, protein carbonyl content and glutathione-S-transferase, superoxide dismutase and catalase activities were quantified at the insect’s third larval stage. Our data showed that protein carbonyl content varied from 2.70 nmol/mg protein in the control group to 59.11 nmol/mg protein in the group fed with fresh leaf extract signifying induction of oxidative stress. All extracts increased the levels of all antioxidant enzymes and decreased the amounts of total protein. Meanwhile, the group fed with the freeze-dried extract showed no significant difference in the levels of total protein and protein carbonyl content except at the 50 mg/l concentration of the extract. Moreover, this group had superoxide dismutase and catalase activities 4 to 5 times higher than in the control group. In conclusion, induction of oxidative stress indicates that the fresh form of C. depressa leaves may have potential as a natural pesticide, whereas induction of endogenous antioxidant enzymes by the freeze-dried extract suggest its potential as an antioxidant.


2021 ◽  
Vol 11 (2) ◽  
pp. 164
Author(s):  
Jae-Hoon Jeong ◽  
Jung-Hoon Koo ◽  
Jang Soo Yook ◽  
Joon-Yong Cho ◽  
Eun-Bum Kang

Exercise and antioxidants have health benefits that improve cognitive impairment and may act synergistically. In this study, we examined the effects of treadmill exercise (TE) and mitochondria-targeted antioxidant mitoquinone (MitoQ), individually or combined, on learning and memory, mitochondrial dynamics, NADPH oxidase activity, and neuroinflammation and antioxidant activity in the hippocampus of D-galactose-induced aging rats. TE alone and TE combined with MitoQ in aging rats reduced mitochondrial fission factors (Drp1, Fis1) and increased mitochondrial fusion factors (Mfn1, Mfn2, Opa1). These groups also exhibited improved NADPH oxidase activity and antioxidant activity (SOD-2, catalase). TE or MitoQ alone decreased neuroinflammatory response (COX-2, TNF-α), but the suppression was greater with their combination. In addition, aging-increased neuroinflammation in the dentate gyrus was decreased in TE but not MitoQ treatment. Learning and memory tests showed that, contrarily, MitoQ alone demonstrated some similar effects to TE but not a definitive improvement. In conclusion, this study demonstrated that MitoQ exerted some positive effects on aging when used as an isolated treatment, but TE had a more effective role on cognitive impairment, oxidative stress, inflammation, and mitochondria dysfunction. Our findings suggest that the combination of TE and MitoQ exerted no synergistic effects and indicated regular exercise should be the first priority in neuroprotection of age-related cognitive decline.


Author(s):  
Pullaiah P. ◽  
Suchitra M. M. ◽  
Siddhartha Kumar B.

Background: Oxidative stress (OS) has an important role in the pathogenesis and progression of rheumatoid arthritis (RA). OS causes protein modification, thereby impairing the biological functions of the protein. This study was conducted to assess the oxidatively modified protein as protein carbonyl content and the antioxidant status as protein thiols, and to study the association between protein carbonyls and protein thiols in RA.Methods: Newly diagnosed RA patients who were not taking any disease modifying anti-rheumatic drugs were included into the study group (n=45) along with age and sex matched healthy controls (n=45). Serum protein carbonyl content and protein thiols were estimated.Results: Elevated protein carbonyl content and decreased protein thiol levels (p<0.001) were observed in RA. A significant negative correlation was observed between protein carbonyl content and protein thiol levels (p<0.001).Conclusions: Oxidative stress in RA is evidenced by enhanced protein oxidation and decreased antioxidant protein thiol levels. Decreased protein thiols may also reflect protein modifications leading to compromise in the antioxidant properties. This oxidant and antioxidant imbalance needs to be addressed by therapeutic interventions to prevent disease progression.


Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Dongmei Liu ◽  
Lie Gao ◽  
Kurtis G Cornish ◽  
Irving H Zucker

In a previous study, we showed that Ang II type I receptor (AT1R) expression increased in the rostral ventrolateral medulla (RVLM) of chronic heart failure (CHF) rabbits and in normal rabbits infused with intracerebroventricular (ICV) Angiotensin II (AngII). The present study investigated if oxidative stress plays a role in Ang II induced AT1R upregulation and its relationship to the transcription factor activator protein 1 (AP1) in CHF rabbits and in the CATHa neuronal cell line. In neuronal cell cultures, Ang II significantly increased AT1R mRNA by 153 ± 22%, P <0.01; c-Jun mRNA by 90 ± 10%, P < 0.01; NADPH oxidase activity by 126 ± 43%, P < 0.01 versus untreated cells; Tempol, Apocynin and the AP 1 inhibitor Tanshinone II reversed the increased AT1R, c-Jun expression and NADPH oxidase activity induced by AngII. We examined the effect of ICV Tempol on expression of these proteins in the RVLM of CHF rabbits. Compared to untreated CHF rabbits Tempol significantly decreased AT1R protein expression (0.88±0.16 vs. 1.6±0.29, P <0.05), phosphorylated Jnk protein (0.10±0.02 vs. 0.31±0.10, P <0.05), and phosphorylated c-Jun (0.02±0.001 vs. 0.14±0.05, P <0.05). These data suggest that Ang II induces AT1R upregulation at the transcriptional level by activation of oxidative stress and AP1 in both cultured cells and in intact brain. Antioxidant agents may be beneficial in CHF by decreasing AT1R expression through the Jnk and AP1 pathway.


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Julie Chao ◽  
Youming Guo ◽  
Lee Chao

Kallistatin was identified in human plasma as a tissue kallikrein-binding protein and a serine proteinase inhibitor. Kallistatin exerts pleiotropic effects on angiogenesis, oxidative stress, inflammation, apoptosis, fibrosis, and tumor growth. Kallistatin levels are markedly reduced in patients with coronary artery disease, sepsis, diabetic retinopathy, inflammatory bowel disease, pneumonia, and cancer. Moreover, plasma kallistatin levels are positively associated with leukocyte telomere length in young African Americans, indicating the involvement of kallistatin in aging. In addition, kallistatin treatment promotes vascular repair by increasing the migration and function of endothelial progenitor cells (EPCs). Kallistatin via its heparin-binding site antagonizes TNF-α-induced senescence and superoxide formation, while kallistatin’s active site is essential for inhibiting miR-34a synthesis, thus elevating sirtuin 1 (SIRT1)/eNOS synthesis in EPCs. Kallistatin inhibits oxidative stress-induced cellular senescence by upregulating Let-7g synthesis, leading to modulate Let-7g-mediated miR-34a-SIRT1-eNOS signaling pathway in human endothelial cells. Exogenous kallistatin administration attenuates vascular injury and senescence in association with increased SIRT1 and eNOS levels and reduced miR-34a synthesis and NADPH oxidase activity, as well as TNF-α and ICAM-1 expression in the aortas of streptozotocin- (STZ-) induced diabetic mice. Conversely, endothelial-specific depletion of kallistatin aggravates vascular senescence, oxidative stress, and inflammation, with further reduction of Let-7g, SIRT1, and eNOS and elevation of miR-34a in mouse lung endothelial cells. Furthermore, systemic depletion of kallistatin exacerbates aortic injury, senescence, NADPH oxidase activity, and inflammatory gene expression in STZ-induced diabetic mice. These findings indicate that endogenous kallistatin displays a novel role in protection against vascular injury and senescence by inhibiting oxidative stress and inflammation.


2015 ◽  
Vol 86 ◽  
pp. 352-361 ◽  
Author(s):  
Julio Madrigal-Matute ◽  
Carlos-Ernesto Fernandez-Garcia ◽  
Luis Miguel Blanco-Colio ◽  
Elena Burillo ◽  
Ana Fortuño ◽  
...  

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3319-3319
Author(s):  
Clara Lo ◽  
Bing Zhang ◽  
Kristina Cusmano-Ozog ◽  
Wendy Wong ◽  
Michael Jeng ◽  
...  

Abstract Abstract 3319 Background: An unpredictable subset of patients (∼20–30%) with pediatric immune thrombocytopenia (ITP) progress to chronic ITP; this increases the risk of morbidity and mortality from bleeding, long-term immunomodulation, and/or splenectomy. Furthermore, treatments such as chronic steroid therapy often result in intolerable side effects, raising the need for targeted therapies. We previously tested a novel list of genes that might predict progression to chronic ITP (Zhang et al Blood 2011). Oxidative stress (OS)-related pathways were among those most significantly perturbed in chronic ITP. For further evaluation of the role of OS in ITP, we measured glutathione as a marker of redox capacity and protein carbonyl content as a marker of oxidative cell damage. Methods: Pediatric patients with primary ITP were included, with exclusion of subjects with secondary thrombocytopenia, other autoimmune disorders (ie, lupus), or other chronic illnesses. Healthy pediatric volunteers were recruited as controls. Patients had blood draws within 1 month from ITP diagnosis. Reduced (GSH) to oxidized (GSSG) glutathione ratios were measured from whole blood by tandem mass-spectrometry. Protein carbonyl content (PCC) levels were measured from platelet-rich plasma by enzyme-linked immunosorbent assay (ELISA). Subjects were followed up to 15 months from diagnosis and monitored for disease resolution or progression. Chronic ITP was defined as thrombocytopenia (platelets <100,000/μL) lasting at least 12 months from diagnosis (Rodegheiro et al Blood 2009). Acute ITP was defined as thrombocytopenia resolving within 12 months from diagnosis. Statistical significance was defined as p<0.05. Results: Between July 2009 and December 2011, 67 pediatric patients with ITP were recruited. Thirty-four patients had acute ITP, and 33 patients progressed to chronic ITP. The median age of patients was 7 years (range 18 months – 17 years). Sixty-three percent were female, 37% were male. Twenty-four pediatric controls were also recruited (46% female, 54% male). The median age of controls was 8 years (range 5 years – 17 years). Patients with ITP had significantly lower GSH:GSSG ratios compared to controls, and patients with chronic ITP had lower GSH:GSSG ratios compared to those with acute ITP (Figure 1). Furthermore, patients with ITP had significantly higher PCC levels compared to controls (Figure 2). Conclusions: This data provides further evidence for a role of oxidative stress (OS) in the pathophysiology of ITP. Furthermore, decreased redox capacity, as evidenced by the decreased glutathione ratios, may be associated with progression to chronic ITP. Reactive oxidative species (ROS) may be important in the pathogenesis of autoimmunity in ITP; oxidatively altered cellular by-products induce pathogenic antibodies and become immunogenic. This also raises a potential anti-oxidant mechanism of therapy, which may play a greater role in chronic ITP treatment. Increased understanding of OS in pediatric ITP may reveal markers of disease progression, highlighting those at greatest risk for chronic ITP and creating a role for targeted therapy. Disclosures: No relevant conflicts of interest to declare.


2006 ◽  
Vol 164 ◽  
pp. S136
Author(s):  
Vügar Aliyev ◽  
Banuçiçek Yücesan ◽  
Şebnem Ş. Çeçen ◽  
Ayşe Karakuş ◽  
Serap Yalçın ◽  
...  

2008 ◽  
Vol 295 (1) ◽  
pp. E103-E109 ◽  
Author(s):  
Adam Whaley-Connell ◽  
Javad Habibi ◽  
Shawna A. Cooper ◽  
Vincent G. DeMarco ◽  
Melvin R. Hayden ◽  
...  

Angiotensin II (Ang II) stimulation of the Ang type 1 receptor (AT1R) facilitates myocardial remodeling through NADPH oxidase-mediated generation of oxidative stress. Components of the renin-angiotensin system constitute an autocrine/paracrine unit in the myocardium, including renin, which is the rate-limiting step in the generation of Ang II. This investigation sought to determine whether cardiac oxidative stress and cellular remodeling could be attenuated by in vivo renin inhibition and/or AT1R blockade in a rodent model of chronically elevated tissue Ang II levels, the transgenic (mRen2)27 rat (Ren2). The Ren2 overexpresses the mouse renin transgene with resultant hypertension, insulin resistance, and cardiovascular damage. Young (6- to 7-wk-old) heterozygous (+/−) male Ren2 and age-matched Sprague-Dawley rats were treated with the renin inhibitor aliskiren, which has high preferential affinity for human and mouse renin, an AT1R blocker, irbesartan, or placebo for 3 wk. Myocardial NADPH oxidase activity and immunostaining for NADPH oxidase subunits and 3-nitrotyrosine were evaluated and remodeling changes assessed by light and transmission electron microscopy. Blood pressure, myocardial NADPH oxidase activity and subunit immunostaining, 3-nitrotyrosine, perivascular fibrosis, mitochondrial content, and markers of activity were significantly increased in Ren2 compared with SD littermates. Both renin inhibition and blockade of the AT1R significantly attenuated cardiac functional and structural alterations, although irbesartan treatment resulted in greater reductions of both blood pressure and markers of oxidative stress. Collectively, these data suggest that both reduce changes driven, in part, by Ang II-mediated increases in NADPH oxidase and, in part, increases in blood pressure.


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