Antisickling property of fetal hemoglobin enhances nitric oxide bioavailability and ameliorates organ oxidative stress in transgenic-knockout sickle mice

In sickle cell disease (SCD), the events originating from hemoglobin S polymerization and intravascular sickling lead to reperfusion injury, hemolysis, decreased nitric oxide (NO) bioavailability, and oxidative stress. Oxidative stress is implicated as a contributing factor to multiple organ damage in SCD. We hypothesize that inhibition of sickling by genetic manipulation to enhance antisickling fetal hemoglobin (HbF) expression will have an ameliorating effect on oxidative stress by decreasing intravascular sickling and hemolysis and enhancing NO bioavailability. We tested this hypothesis in BERK (Berkeley) mice expressing exclusively human α- and βS-globins and varying levels of HbF, i.e., BERK (<1% HbF), BERKγM (20% HbF) and BERKγH (40% HbF). Intravascular sickling showed a distinct decrease with increased expression of HbF, which was accompanied by decreased hemolysis and increased NO metabolites (NOx) levels. Consistent with decreased intravascular sickling and increased NO bioavailability, BERKγM and BERKγH mice showed markedly decreased lipid peroxidation accompanied by increased activity/levels of antioxidants [superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), and reduced glutathione (GSH)] in the muscle, kidney, and liver compared with BERK mice ( P < 0.05–0.0001). NOxlevels showed a strong inverse correlation with hemolytic rate and oxidative stress. Decreased oxidative stress in the presence of elevated HbF levels led to an anti-inflammatory effect as evidenced by decreased peripheral leukocyte counts. These results show that the protective effect of HbF is mediated primarily by decreasing intravascular sickling resulting in decreased oxidative stress and increased NO bioavailability.

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Reduced Oxidative Stress and Enhanced Nitric Oxide (NO) Bioavailability in Transgenic-Knockout Sickle Mice Expressing Fetal Hemoglobin (HbF) Is Mediated by Decreased Sickling and Hemolysis.

Blood ◽

10.1182/blood.v110.11.842.842 ◽

2007 ◽

Vol 110 (11) ◽

pp. 842-842

Author(s):

Trisha Dasgupta ◽

Mary E. Fabry ◽

Dhananjay K. Kaul

Keyword(s):

Oxidative Stress ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Genetic Manipulation ◽

Fetal Hemoglobin ◽

Organ Damage ◽

Multiple Organ ◽

Protective Effects ◽

Cell Disease ◽

No Bioavailability

Abstract The primary event in the vaso-occlusive pathophysiology of sickle cell disease (SCD) is polymerization of hemoglobin S under deoxygenated conditions. In SCD, sub-clinical transient vaso-occlusive events caused by red cell sickling are likely to be more frequent resulting in “reperfusion injury” that generates reactive oxygen species and results in chronic oxidative stress that will contribute to multiple organ damage. In fact, previous studies have suggested that sickling is etiologic to repefusion injury and oxidative stress (Kaul and Hebbel, JCI, 2000), although the effect of antisickling therapy on oxidative stress has not been evaluated. Increasing the levels of antisickling fetal hemoglobin (HbF) by hydroxyurea therapy markedly reduces polymer formation. HbF exerts an ameliorating effect in sickle cell disease patients both on red cells and in the prevention of multiple organ damage. Here, we hypothesize that induction of HbF by genetic manipulation (in the absence of pharmacological manipulation) will reduce organ oxidative stress by reducing sickling and hemolysis, and thereby increase NO bioavailability. To test our hypothesis, we measured activity of selected antioxidants and lipid peroxidation (LPO) in BERK mice expressing exclusively human α- and βS-globins and varying levels of HbF, i.e., BERK (<1% HbF), BERKγM (20% HbF) and BERKγH (40% HbF). Percent sickled cells in venous samples (drawn in 2.5% glutaraldehyde solution in 0.1M cacodylate buffer) showed a distinct decrease with increased %HbF (P<0.05, multiple comparisons). Consistent with maximal sickling, BERK mice showed 5.4–6.9-fold increase in LPO in various tissues (muscle, kidney and liver) compared with C57BL controls (P<0.001). In contrast, BERKγM and BERKγH mice showed a marked decrease (73% and 80%, respectively) in LPO compared with BERK mice (P<0.001). Also, activity/levels of antioxidants (superoxide dismutase [SOD], catalase, glutathione peroxidase [GPx] and reduced glutathione [GSH]) showed significant decreases in BERK mice (P<0.001–0.00001). On the other hand, BERKγM and BERKγH mice showed significant increases in antioxidant activity (P<0.05–0.0001). Induction of HbF was associated with increased levels of NO metabolites (NOx) and reduced hemolysis; the latter is in agreement with our previous observations in BERKγM mice (Kaul et al. JCI, 2004). These results strongly suggest that reduced sickling and hemolysis in the presence of HbF cause increased NO bioavailability. NO is well known to exert antioxidative effects. Thus, we show for the first time that the induction of antisickling HbF leads to an increase in NO bioavailability and a decrease in oxidative stress, and that these protective effects are mediated primarily by reduced intravascular sickling.

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Arginine therapy of transgenic-knockout sickle mice improves microvascular function by reducing non-nitric oxide vasodilators, hemolysis, and oxidative stress

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00162.2008 ◽

2008 ◽

Vol 295 (1) ◽

pp. H39-H47 ◽

Cited By ~ 51

Author(s):

Dhananjay K. Kaul ◽

Xiaoqin Zhang ◽

Trisha Dasgupta ◽

Mary E. Fabry

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Vascular Reactivity ◽

Microvascular Function ◽

Cell Disease ◽

No Bioavailability ◽

Cox 2 ◽

And Oxidative Stress

In sickle cell disease, nitric oxide (NO) depletion by cell-free plasma hemoglobin and/or oxygen radicals is associated with arginine deficiency, impaired NO bioavailability, and chronic oxidative stress. In transgenic-knockout sickle (BERK) mice that express exclusively human α- and βS-globins, reduced NO bioavailability is associated with induction of non-NO vasodilator enzyme, cyclooxygenase (COX)-2, and impaired NO-mediated vascular reactivity. We hypothesized that enhanced NO bioavailability in sickle mice will abate activity of non-NO vasodilators, improve vascular reactivity, decrease hemolysis, and reduce oxidative stress. Arginine treatment of BERK mice (5% arginine in mouse chow for 15 days) significantly reduced expression of non-NO vasodilators COX-2 and heme oxygenase-1. The decreased COX-2 expression resulted in reduced prostaglandin E2(PGE2) levels. The reduced expression of non-NO vasodilators was associated with significantly decreased arteriolar dilation and markedly improved NO-mediated vascular reactivity. Arginine markedly decreased hemolysis and oxidative stress and enhanced NO bioavailability. Importantly, arteriolar diameter response to a NO donor (sodium nitroprusside) was strongly correlated with hemolytic rate (and nitrotyrosine formation), suggesting that the improved microvascular function was a response to reduced hemolysis. These results provide a strong rationale for therapeutic use of arginine in sickle cell disease and other hemolytic diseases.

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Tetrahydrocurcumin alleviates hypertension, aortic stiffening and oxidative stress in rats with nitric oxide deficiency

Hypertension Research ◽

10.1038/hr.2011.180 ◽

2011 ◽

Vol 35 (4) ◽

pp. 418-425 ◽

Cited By ~ 44

Author(s):

Saowanee Nakmareong ◽

Upa Kukongviriyapan ◽

Poungrat Pakdeechote ◽

Veerapol Kukongviriyapan ◽

Bunkerd Kongyingyoes ◽

...

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Nitric Oxide Deficiency ◽

Aortic Stiffening ◽

And Oxidative Stress

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Differential susceptibility of a few members of the nasuta–albomicans complex of Drosophila to paraquat-induced lethality and oxidative stress

Genome ◽

10.1139/g11-049 ◽

2011 ◽

Vol 54 (10) ◽

pp. 829-835 ◽

Cited By ~ 2

Author(s):

Mysore S. Ranjini ◽

Ravikumar Hosamani ◽

Muralidhara ◽

Nallur B. Ramachandra

Keyword(s):

Oxidative Stress ◽

Biochemical Analysis ◽

Reduced Glutathione ◽

Differential Susceptibility ◽

Activity Levels ◽

Oxygen Species ◽

Stress Markers ◽

The Status ◽

Markers Of Oxidative Stress ◽

And Oxidative Stress

The evolution of karyotypically stabilized short-lived (SL) and long-lived (LL) cytoraces in the laboratory have been established and validated through our previous lifespan studies. In the present investigation, we examined the possible reason(s) for the differential longevity among selected members of SL and LL cytoraces, employing the well known paraquat (PQ) resistance bioassay. Exposure of these races to varying concentrations of PQ revealed relatively higher resistance among LL cytoraces than SL cytoraces, as evident by the lower incidence of mortality. Biochemical analysis for endogenous markers of oxidative stress revealed that LL-2 cytorace exhibited lower reactive oxygen species (ROS) and lipid peroxidation (LPO) levels, higher activity levels of superoxide dismutase (SOD), and coupled with higher levels of reduced glutathione (GSH) compared with the levels found in SL-2 cytorace. These findings suggest that the higher susceptibility of SL cytoraces to PQ challenge may be, at least in part, related to the higher endogenous levels of oxidative stress markers. Although the precise mechanisms responsible for the longer longevity among LL cytoraces of the nasuta–albomicans complex of Drosophila merits further investigation, our data suggest that the relatively longer lifespan may be related to the status of endogenous markers that renders them more resistant towards oxidative-stress-mediated lethality, as evident in the PQ assay.

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Mercury Exposure and Endothelial Dysfunction

International Journal of Toxicology ◽

10.1177/1091581815589766 ◽

2015 ◽

Vol 34 (4) ◽

pp. 300-307 ◽

Cited By ~ 13

Author(s):

Swati Omanwar ◽

M. Fahim

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Endothelial Dysfunction ◽

Vascular Endothelium ◽

Circulatory System ◽

Vital Role ◽

Mercury Exposure ◽

And Function ◽

The Impact ◽

And Oxidative Stress

Vascular endothelium plays a vital role in the organization and function of the blood vessel and maintains homeostasis of the circulatory system and normal arterial function. Functional disruption of the endothelium is recognized as the beginning event that triggers the development of consequent cardiovascular disease (CVD) including atherosclerosis and coronary heart disease. There is a growing data associating mercury exposure with endothelial dysfunction and higher risk of CVD. This review explores and evaluates the impact of mercury exposure on CVD and endothelial function, highlighting the interplay of nitric oxide and oxidative stress.

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Melatonin, Nitric Oxide Synthase and Oxidative Stress: Implications in Aging

Catecholamine Research - Advances in Behavioral Biology ◽

10.1007/978-1-4757-3538-3_57 ◽

2002 ◽

pp. 245-248

Author(s):

D. K. Lahiri ◽

Y-.W. Ge ◽

J. I. Nurnberger ◽

E. Y. Yang ◽

S. C. Bondy

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Oxide Synthase ◽

And Oxidative Stress

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Recurrent insulin-induced hypoglycemia induces AngII and COX2 leading to renal (pro)renin receptor expression and oxidative stress

International Journal of Medicine ◽

10.14419/ijm.v5i1.6858 ◽

2017 ◽

Vol 5 (1) ◽

pp. 71 ◽

Cited By ~ 1

Author(s):

Wael Alanazi ◽

Mohammad Uddin ◽

Selim Fakhruddin ◽

Keith Jackson

Keyword(s):

Oxidative Stress ◽

Nadph Oxidase ◽

Kidney Injury ◽

Organ Damage ◽

Day Surgery ◽

Receptor Expression ◽

Sprague Dawley ◽

Subunit Expression ◽

Renal Biomarker ◽

And Oxidative Stress

Background: Recurrent insulin-induced hypoglycemia (RIIH) is an avoidable consequence in the therapeutic management of diabetes mellitus. RIIH has been implicated in causing hypertension through an increase in renal and systemic AngII production.Objective: The present study was performed to assess the hypothesis that chronic insulin treatment enhances AngII and COX2 formation which in turn increases (pro) renin receptor (PRR) expression and NADPH oxidase-mediated oxidative stress, leading to renal and cardiac injury.Methods: The present studies were conducted in Male Sprague Dawley rats treated with daily subcutaneous injections of 7u/kg insulin or saline for 14 days. On the 14th day, surgery was performed for treatment infusion (captopril 12mg/kg, NS398 0.3mg/kg or vehicle), and renal interstitial fluid sample and urine collections for biomarker measurements. At the end of the experiments, kidneys and hearts were harvested to evaluate PRR and NOX2 (NADPH oxidase subunit) expression and oxidative stress.Results: We found that RIIH enhanced AngII and COX2 activity, leading to renal PRR expression and NADPH oxidase-induced oxidative stress in the heart and kidney. 8-isoprostane was evaluated as a renal biomarker of oxidative stress, which was induced in insulin treated animals and modulated by captopril and NS398. In addition, there was a slight increase in NGAL, a urinary biomarker of acute kidney injury (AKI), in insulin treated animals when compared to control.Conclusion: These results demonstrate that RIIH induces renal PRR expression and oxidative stress through increasing AngII and COX2 in the heart and kidney, leading to end-organ damage.

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