scholarly journals Alpha Lipoic Acid Improves Endothelial Function and Oxidative Stress in Mice Exposed to Chronic Intermittent Hypoxia

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Mohammad Badran ◽  
Bisher Abuyassin ◽  
Saeid Golbidi ◽  
Najib Ayas ◽  
Ismail Laher
Keyword(s):  
Oxidative Stress ◽  
Nitric Oxide ◽  
Endothelial Dysfunction ◽  
Endothelial Function ◽  
Intermittent Hypoxia ◽  
Chronic Intermittent Hypoxia ◽  
Alpha Lipoic Acid ◽  
Systemic Oxidative Stress ◽  
Enos Uncoupling ◽  
And Oxidative Stress

Objective. Obstructive sleep apnea (OSA) is characterized by recurrent airway collapse that causes chronic intermittent hypoxia (CIH). OSA is associated with systemic inflammation and oxidative stress resulting in endothelial dysfunction and cardiovascular disease (CVD). Alpha lipoic acid (ALA) is a potent antioxidant with anti-inflammatory properties. We hypothesized that dietary ALA can improve endothelial function of mice exposed to CIH. Methods. Mice were exposed to either CIH or intermittent air (IA) and treated with dietary ALA (0.2% w/w) or a regular chow diet for 8 weeks. Endothelial function, endothelial nitric oxide (eNOS) uncoupling, systemic oxidative stress, systemic inflammation, aortic expression of inflammatory cytokines, and antioxidant enzymes were measured after 8 weeks. Results. Mice exposed to CIH exhibited endothelial dysfunction accompanied by systemic oxidative stress and inflammation as well as increased aortic expression of inflammatory cytokines. Furthermore, CIH led to eNOS uncoupling. Treatment with dietary ALA reversed endothelial dysfunction in mice exposed to CIH, lowered systemic oxidative stress and inflammation, prevented the increases of inflammatory cytokine gene expression, increased the expression of antioxidant enzymes, and preserved eNOS in a coupled state. Conclusion. ALA attenuates endothelial dysfunction by preventing oxidative stress and inflammation and restoring nitric oxide bioavailability in mice exposed to CIH. Our data suggests the potential beneficial use of ALA as adjunctive therapy in OSA.

scholarly journals Uncoupling of Vascular Nitric Oxide Synthase Caused by Intermittent Hypoxia

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Mohammad Badran ◽  
Bisher Abuyassin ◽  
Saeid Golbidi ◽  
Najib Ayas ◽  
Ismail Laher
Keyword(s):  
Nitric Oxide ◽  
Endothelial Dysfunction ◽  
Intermittent Hypoxia ◽  
Asymmetric Dimethylarginine ◽  
Chronic Intermittent Hypoxia ◽  
No Production ◽  
Diabetic Mice ◽  
Enos Uncoupling ◽  
Obstructive Sleep ◽  
Oxide Synthase

Objective. Obstructive sleep apnea (OSA), characterized by chronic intermittent hypoxia (CIH), is often present in diabetic (DB) patients. Both conditions are associated with endothelial dysfunction and cardiovascular disease. We hypothesized that diabetic endothelial dysfunction is further compromised by CIH.Methods. Adult male diabetic (BKS.Cg-Dock7m+/+Leprdb/J) (db/db) mice (10 weeks old) and their heterozygote littermates were subjected to CIH or intermittent air (IA) for 8 weeks. Mice were separated into 4 groups: IA (intermittent air nondiabetic), IH (intermittent hypoxia nondiabetic), IADB (intermittent air diabetic), and IHDB (intermittent hypoxia diabetic) groups. Endothelium-dependent and endothelium-independent relaxation and modulation by basal nitric oxide (NO) were analyzed using wire myograph. Plasma 8-isoprostane, interleukin-6 (IL-6), and asymmetric dimethylarginine (ADMA) were measured using ELISA. Uncoupling of eNOS was measured using dihydroethidium (DHE) staining.Results. Endothelium-dependent vasodilation and basal NO production were significantly impaired in the IH and IADB group compared to IA group but was more pronounced in IHDB group. Levels of 8-isoprostane, IL-6, ADMA, and eNOS uncoupling were ≈2-fold higher in IH and IADB groups and were further increased in the IHDB group.Conclusion. Endothelial dysfunction is more pronounced in diabetic mice subjected to CIH compared to diabetic or CIH mice alone. Oxidative stress, ADMA, and eNOS uncoupling were exacerbated by CIH in diabetic mice.

Early experimental obesity is associated with coronary endothelial dysfunction and oxidative stress

2007 ◽  
Vol 292 (2) ◽  
pp. H904-H911 ◽  
Author(s):  
Offer Galili ◽  
Daniele Versari ◽  
Katherine J. Sattler ◽  
Monica L. Olson ◽  
Dallit Mannheim ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Insulin Resistance ◽  
Cardiovascular Risk ◽  
Insulin Sensitivity ◽  
Endothelial Dysfunction ◽  
Endothelial Function ◽  
Microvascular Permeability ◽  
Systemic Oxidative Stress ◽  
Coronary Endothelium ◽  
And Oxidative Stress

Obesity is independently associated with increased cardiovascular risk. However, since established obesity clusters with various cardiovascular risk factors, configuring the metabolic syndrome, the early effects of obesity on vascular function are still poorly understood. The current study was designed to evaluate the effect of early obesity on coronary endothelial function in a new animal model of swine obesity. As to method, juvenile domestic crossbred pigs were randomized to either high-fat/high-calorie diet (HF) or normal chow diet for 12 wk. Coronary microvascular permeability and abdominal wall fat were determined by using electron beam computerized tomography. Epicardial endothelial function and oxidative stress were measured in vitro. Systemic oxidative stress, renin-angiotensin activity, leptin levels, and parameters of insulin sensitivity were evaluated. As a result, HF pigs were characterized by abdominal obesity, hypertension, and elevated plasma lysophosphatidylcholine and leptin in the presence of increased insulin sensitivity. Coronary endothelium-dependent vasorelaxation was reduced in HF pigs and myocardial microvascular permeability increased compared with those values in normal pigs. Systemic redox status in HF pigs was similar to that in normal pigs, whereas the coronary endothelium demonstrated higher content of superoxide anions, nitrotyrosine, and NADPH-oxidase subunits, indicating increased tissue oxidative stress. In conclusion, the current study shows that early obesity is characterized by increased vascular oxidative stress and endothelial dysfunction in association with increased levels of leptin and before the development of insulin resistance and systemic oxidative stress. Vascular dysfunction is therefore an early manifestation of obesity and might contribute to the increased cardiovascular risk, independently of insulin resistance.

Mercury Exposure and Endothelial Dysfunction

2015 ◽  
Vol 34 (4) ◽  
pp. 300-307 ◽  
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.

Tackling endothelial dysfunction by modulating NOS uncoupling: new insights into its pathogenesis and therapeutic possibilities

2012 ◽  
Vol 302 (5) ◽  
pp. E481-E495 ◽  
Author(s):  
Rinrada Kietadisorn ◽  
Rio P. Juni ◽  
An L. Moens
Keyword(s):  
Nitric Oxide ◽  
Endothelial Dysfunction ◽  
Endothelial Function ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Therapeutic Interventions ◽  
Enos Uncoupling ◽  
Underlying Causes ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Endothelial nitric oxide synthase (eNOS) serves as a critical enzyme in maintaining vascular pressure by producing nitric oxide (NO); hence, it has a crucial role in the regulation of endothelial function. The bioavailability of eNOS-derived NO is crucial for this function and might be affected at multiple levels. Uncoupling of eNOS, with subsequently less NO and more superoxide generation, is one of the major underlying causes of endothelial dysfunction found in atherosclerosis, diabetes, hypertension, cigarette smoking, hyperhomocysteinemia, and ischemia/reperfusion injury. Therefore, modulating eNOS uncoupling by stabilizing eNOS activity, enhancing its substrate, cofactors, and transcription, and reversing uncoupled eNOS are attractive therapeutic approaches to improve endothelial function. This review provides an extensive overview of the important role of eNOS uncoupling in the pathogenesis of endothelial dysfunction and the potential therapeutic interventions to modulate eNOS for tackling endothelial dysfunction.

scholarly journals Arginase inhibition restores NOS coupling and reverses endothelial dysfunction and vascular stiffness in old rats

2009 ◽  
Vol 107 (4) ◽  
pp. 1249-1257 ◽  
Author(s):  
Jae Hyung Kim ◽  
Lukasz J. Bugaj ◽  
Young Jun Oh ◽  
Trinity J. Bivalacqua ◽  
Sungwoo Ryoo ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Dysfunction ◽  
Endothelial Function ◽  
Vascular Stiffness ◽  
Arginase Activity ◽  
Young Rats ◽  
Arginase 1 ◽  
Enos Uncoupling ◽  
Old Rats

There is increasing evidence that upregulation of arginase contributes to impaired endothelial function in aging. In this study, we demonstrate that arginase upregulation leads to endothelial nitric oxide synthase (eNOS) uncoupling and that in vivo chronic inhibition of arginase restores nitroso-redox balance, improves endothelial function, and increases vascular compliance in old rats. Arginase activity in old rats was significantly increased compared with that shown in young rats. Old rats had significantly lower nitric oxide (NO) and higher superoxide (O2−) production than young. Acute inhibition of both NOS, with NG-nitro-l-arginine methyl ester, and arginase, with 2( S)-amino- 6-boronohexanoic acid (ABH), significantly reduced O2− production in old rats but not in young. In addition, the ratio of eNOS dimer to monomer in old rats was significantly decreased compared with that shown in young rats. These results suggest that eNOS was uncoupled in old rats. Although the expression of arginase 1 and eNOS was similar in young and old rats, inducible NOS (iNOS) was significantly upregulated. Furthermore, S-nitrosylation of arginase 1 was significantly elevated in old rats. These findings support our previously published finding that iNOS nitrosylates and activates arginase 1 (Santhanam et al., Circ Res 101: 692–702, 2007). Chronic arginase inhibition in old rats preserved eNOS dimer-to-monomer ratio and significantly reduced O2− production and enhanced endothelial-dependent vasorelaxation to ACh. In addition, ABH significantly reduced vascular stiffness in old rats. These data indicate that iNOS-dependent S-nitrosylation of arginase 1 and the increase in arginase activity lead to eNOS uncoupling, contributing to the nitroso-redox imbalance, endothelial dysfunction, and vascular stiffness observed in vascular aging. We suggest that arginase is a viable target for therapy in age-dependent vascular stiffness.

scholarly journals Hydrogen Gas Alleviates Chronic Intermittent Hypoxia-Induced Renal Injury through Reducing Iron Overload

Molecules ◽  
2019 ◽  
Vol 24 (6) ◽  
pp. 1184 ◽  
Author(s):  
Peng Guan ◽  
Zhi-Min Sun ◽  
Li-Fei Luo ◽  
Ya-Shuo Zhao ◽  
Sheng-Chang Yang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Iron Overload ◽  
Renal Injury ◽  
Intermittent Hypoxia ◽  
Hydrogen Gas ◽  
Chronic Intermittent Hypoxia ◽  
Protective Effects ◽  
Divalent Metal Transporter 1 ◽  
Divalent Metal Transporter ◽  
And Oxidative Stress

Iron-induced oxidative stress has been found to be a central player in the pathogenesis of kidney injury. Recent studies have indicated H2 can be used as a novel antioxidant to protect cells. The present study was designed to investigate the protective effects of H2 against chronic intermittent hypoxia (CIH)-induced renal injury and its correlation mechanism involved in iron metabolism. We found that CIH-induced renal iron overloaded along with increased apoptosis and oxidative stress. Iron accumulates mainly occurred in the proximal tubule epithelial cells of rats as showed by Perl’s stain. Moreover, we found that CIH could promote renal transferrin receptor and divalent metal transporter-1 expression, inhibit ceruloplasmin expression. Renal injury, apoptosis and oxidative stress induced by CIH were strikingly attenuated in H2 treated rats. In conclusion, hydrogen may attenuate CIH-induced renal injury at least partially via inhibiting renal iron overload.

scholarly journals Genderspecific differences of homocysteinemia and its influence on oxidative stress parameters and endothelial function in patients with stable forms of coronary heart disease

2017 ◽  
Vol 95 (8) ◽  
pp. 705-712
Author(s):  
Olga L. Belaya ◽  
K. Yu. Bondar ◽  
L. I. Markova ◽  
Z. V. Kuropteva ◽  
L. M. Baider ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Nitric Oxide ◽  
Coronary Heart Disease ◽  
Heart Disease ◽  
Endothelial Dysfunction ◽  
Endothelial Function ◽  
Gas Liquid Chromatography ◽  
Men And Women ◽  
Stable Forms ◽  
Gender Specific

One of the early manifestations of atherosclerotic lesions is endothelial dysfunction developing under conditions of reduced nitric oxide production, hyperhomocysteinemia, and oxidative stress. Bearing in mind high interest shown to gender-specific peculiarities of cardiovascular diseases, it appears important to study the relationship between these features in men and women with stable forms of coronary heart disease (CHD). Material and methods. The study included 102 patients with sable COPD divided into 2 groups (men and women) and 40 practically healthy subjects. Plasma homocysteine levels were measured by high-resolution gas-liquid chromatography with fluorescent detector with the use of Eko-Novo Milikhrom A-02 apparatus (Russia). Standard methods were used to measure plasma lipids, products of their peroxidation (dienic conjugates and products reacting with 2-thibarbituric acid), antioxidant enzymes (glutathioneperoxidase, and superoxide dismutase in erythrocytes), activity of the ceruloplasmin-transferrin system (by electron paramagnetic resonance method), final metabolites of nitric oxide using the Gries reaction. The endothelial function was studies by ultrasound with the evaluation of endothelium-dependent vasodilation. Results. The mean levels of homocystein and final NO metabolites in men with stable CHD were 1.5 times higher (р=0,01) and 12% lower (р = 0,03) than in women. Endothelial dysfunction was more pronounced in men (р< 0,05). Conclusion. Patients with CHD exhibit significant gender-specific differences in blood levels of of homocystein and final NO metabolites as well as in endothelium-dependent vasoreactivity associated with intensification of lipid peroxidation and impairment of antioxidative protection.

scholarly journals Silencing MR-1 Protects against Myocardial Injury Induced by Chronic Intermittent Hypoxia by Targeting Nrf2 through Antioxidant Stress and Anti-Inflammation Pathways

2022 ◽  
Vol 2022 ◽  
pp. 1-11
Author(s):  
Qixue Wang ◽  
Yue Wang ◽  
Jiner Zhang ◽  
Shuo Pan ◽  
Shaofeng Liu
Keyword(s):  
Oxidative Stress ◽  
Intermittent Hypoxia ◽  
Myocardial Injury ◽  
Cardiac Insufficiency ◽  
Inflammatory Factors ◽  
Chronic Intermittent Hypoxia ◽  
Heme Oxygenase 1 ◽  
Stress System ◽  
Antioxidant Stress ◽  
And Oxidative Stress

Background. Patients with obstructive sleep apnea hypopnea syndrome (OSAHS) often have cardiac insufficiency mainly due to hypoxia/reperfusion injury caused by chronic intermittent hypoxia (CIH). Inflammation and oxidative stress are involved in the cardiovascular events of OSAHS patients. Studies have found that myofibrillation regulator-1 (MR-1) participates in the pathological process of OSAHS-induced myocardial injury, but the specific mechanism is still unclear. Methods. We used a CIH-induced rat model to simulate the process of OSAHS disease. Indices of myocardial injury, inflammation, and oxidative stress were detected using quantitative PCR and enzyme-linked immunosorbent assay (ELISA). After administration of adenoassociated viral vector (AAV) encoding silencing RNA against MR-1, we examined expression of the classic antioxidant stress pathway protein NF-E2-related factor 2 (Nrf2) using western blotting. Results. We found that levels of serum inflammatory factors tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-8 were increased, and we further observed disturbance of the oxidative stress system, in which the content of reactive oxygen species (ROS), superoxide dismutase (SOD), reduced glutathione (GSH), and malondialdehyde (MDA) was enhanced in CIH-induced rats. Subsequently, we detected that expression of Nrf2 and heme oxygenase-1 (HO-1) was slightly increased, while the expression of Kelch-like ECH-associated protein 1 (Keap-1) was significantly increased in the CIH model. Interestingly, after administration of silencing MR-1 AAV, the elevated levels of inflammatory factors were reduced, and the disordered oxidative stress system was corrected. Additionally, the expression of Nrf2 and HO-1 was distinctly increased, but the high expression of Keap-1 was decreased. Conclusions. Our research results demonstrate that silencing MR-1 rescued the myocardium the injury from inflammatory and oxidative stress in CIH-induced rats by administration of the Nrf2 signaling pathway.

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