scholarly journals Computational Model of Tyrosine Nitration Resulting from Oxidative Stress and Nitric Oxide Interaction in the Microcirculation

2006 ◽  
Vol 20 (4) ◽  
Author(s):  
Mahendra Kavdia
2012 ◽  
Vol 303 (10) ◽  
pp. L870-L879 ◽  
Author(s):  
Adeleye J. Afolayan ◽  
Annie Eis ◽  
Ru-Jeng Teng ◽  
Ivane Bakhutashvili ◽  
Sushma Kaul ◽  
...  

A rapid increase in the synthesis and release of nitric oxide (NO) facilitates the pulmonary vasodilation that occurs during birth-related transition. Alteration of this transition in persistent pulmonary hypertension of the newborn (PPHN) is associated with impaired function of endothelial nitric oxide synthase (eNOS) and an increase in oxidative stress. We investigated the hypothesis that a decrease in expression and activity of mitochondrial localized manganese superoxide dismutase (MnSOD) in pulmonary artery endothelial cells (PAEC) increases oxidative stress and impairs eNOS function in PPHN. We isolated PAEC and pulmonary arteries from fetal lambs with PPHN induced by prenatal ductus arteriosus ligation or sham ligation (control). We investigated MnSOD expression and activity, tyrosine nitration of MnSOD, and mitochondrial O2− levels in PAEC from control and PPHN lambs. We introduced exogenous MnSOD via an adenoviral vector (ad-MnSOD) transduction into PAEC and pulmonary arteries of PPHN lambs. The effect of ad-MnSOD was investigated on: mitochondrial O2− levels, MnSOD and eNOS expression and activity, intracellular hydrogen peroxide (H2O2) levels, and catalase expression in PAEC. MnSOD mRNA and protein levels and activity were decreased and MnSOD tyrosine nitration was increased in PPHN-PAEC. ad-MnSOD transduction of PPHN-PAEC increased its activity two- to threefold, decreased mitochondrial O2− levels, and increased H2O2 levels and catalase expression. ad-MnSOD transduction improved eNOS expression and function and the relaxation response of PPHN pulmonary arteries. Our observations suggest that decreased MnSOD expression and activity contribute to the endothelial dysfunction observed in PPHN.


2001 ◽  
Vol 12 (9) ◽  
pp. 1892-1899
Author(s):  
GANGMIN DENG ◽  
NOSRATOLA D. VAZIRI ◽  
BAHMAN JABBARI ◽  
ZHEMIN NI ◽  
XIAO-XIN YAN

Abstract. Interaction of reactive oxygen species with nitric oxide promotes nitric oxide inactivation and generation of cytotoxic reactive nitrogen species that attack DNA, lipids, and proteins. Nitration of free tyrosine and tyrosine residues of proteins results in production of nitrotyrosine, which can lead to excitotoxicity and frequently is found in the brain of patients and animals with various degenerative, ischemic, toxic, and other neurologic disorders. According to earlier studies, reactive oxygen species activity is increased and neuronal NO synthase expression in the brain is elevated in animals with chronic renal failure (CRF). It was hypothesized, therefore, that tyrosine nitration must be increased in the uremic brain. This hypothesis was tested, through determination of nitrotyrosine abundance (by Western blot analysis), as well as distribution (by immunohistology), in the cerebrum of rats with CRF 6 wk after 5/6 nephrectomy. The results were compared with those of sham-operated controls and antioxidant (lazaroid)-treated and captopril-treated rats with CRF. Western blot analysis revealed a significant increase in nitrotyrosine abundance in the cerebral cortex of rats with CRF. This was accompanied by an intense nitrotyrosine staining of the neuronal processes, including proximal segments of dendrites, axons, and axon terminals of the cortical neurons. Both antioxidant therapy and captopril administration alleviated oxidative stress (as evidenced by normalization of plasma lipid peroxidation product malondialdehyde) and significantly reduced nitrotyrosine abundance in the cerebral cortex of the treated CRF group. In conclusion, CRF resulted in oxidative stress and increased tyrosine nitration in the cerebral cortex. Antioxidant therapy and angiotensin-converting enzyme inhibition alleviated the CRF-induced oxidative stress and mitigated tyrosine nitration in the rats with CRF.


2017 ◽  
Vol 313 (2) ◽  
pp. F174-F183 ◽  
Author(s):  
Ying Chen ◽  
Jennifer C. Sullivan ◽  
Aurélie Edwards ◽  
Anita T. Layton

The goals of this study were to 1) develop a computational model of solute transport and oxygenation in the kidney of the female spontaneously hypertensive rat (SHR), and 2) apply that model to investigate sex differences in nitric oxide (NO) levels in SHR and their effects on medullary oxygenation and oxidative stress. To accomplish these goals, we first measured NO synthase (NOS) 1 and NOS3 protein expression levels in total renal microvessels of male and female SHR. We found that the expression of both NOS1 and NOS3 is higher in the renal vasculature of females compared with males. To predict the implications of that finding on medullary oxygenation and oxidative stress levels, we developed a detailed computational model of the female SHR kidney. The model was based on a published male kidney model and represents solute transport and the biochemical reactions among O2, NO, and superoxide ([Formula: see text]) in the renal medulla. Model simulations conducted using both male and female SHR kidney models predicted significant radial gradients in interstitial fluid oxygen tension (Po2) and NO and [Formula: see text] concentration in the outer medulla and upper inner medulla. The models also predicted that increases in endothelial NO-generating capacity, even when limited to specific vascular segments, may substantially raise medullary NO and Po2 levels. Other potential sex differences in SHR, including [Formula: see text] production rate, are predicted to significantly impact oxidative stress levels, but effects on NO concentration and Po2 are limited.


2020 ◽  
Vol 16 (9) ◽  
pp. 1319-1327
Author(s):  
Ferdous Khan ◽  
Syed A. Kuddus ◽  
Md. H. Shohag ◽  
Hasan M. Reza ◽  
Murad Hossain

Background: An imbalance between pro-oxidants and antioxidants determines the level of oxidative stress which is implicated in the etiopathogenesis of various neuropsychiatric disorders including depression. Therefore, treatment with antioxidants could potentially improve the balance between pro-oxidants and antioxidants. Objective: The objective of this study was to evaluate the ability of astaxanthin, a potential antioxidant, to reduce reserpine-induced depression in BALB/c mice (Mus musculus). Methods: On the behavioral level, antidepressant property of astaxanthin (50 mg/kg, orally) on reserpine (2 mg/kg, subcutaneously) induced depressed mice was evaluated by Forced Swim Test (FST) and Tail Suspension Test (TST). In the biochemical level, the ability of astaxanthin to mitigate reserpine-induced oxidative stress was evaluated by the measurement of Malondialdehyde (MDA) and nitric oxide (NO) in brain, liver and plasma samples. On the other hand, the efficiency of astaxanthin to replenish glutathione depletion and antioxidant enzyme activity augmentation in the same samples were also investigated. Results: Astaxanthin was able to lower reserpine induced immobility time significantly (p<0.05) in FST and TST. Mice treated with astaxanthin showed significantly (p<0.05) low level of oxidative stress markers such as Malondialdehyde (MDA), Nitric Oxide (NO). Consistently, the level of reduced Glutathione (GSH), and the activity of Superoxide Dismutase (SOD) and catalase were augmented due to the oral administration of astaxanthin. Conclusion: This study suggests that astaxanthin reduces reserpine-induced oxidative stress and therefore might be effective in treating oxidative stress associated depression.


2012 ◽  
Vol 11 (2) ◽  
pp. 161-172 ◽  
Author(s):  
Seyhan Sahan-Firat ◽  
Necmiye Canacankatan ◽  
Belma Korkmaz ◽  
Hatice Yildirim ◽  
Lulufer Tamer ◽  
...  

2011 ◽  
Vol 35 (4) ◽  
pp. 418-425 ◽  
Author(s):  
Saowanee Nakmareong ◽  
Upa Kukongviriyapan ◽  
Poungrat Pakdeechote ◽  
Veerapol Kukongviriyapan ◽  
Bunkerd Kongyingyoes ◽  
...  

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Fujiao Nie ◽  
Jiazhao Yan ◽  
Yanjun Ling ◽  
Zhengrong Liu ◽  
Chaojun Fu ◽  
...  

Abstract Background Diabetic retinopathy (DR) has become a worldwide concern because of the rising prevalence rate of diabetes mellitus (DM). Despite much energy has been committed to DR research, it remains a difficulty for diabetic patients all over the world. Since apoptosis of retinal microvascular pericytes (RMPs) is the early characteristic of DR, this study aimed to reveal the mechanism of Shuangdan Mingmu (SDMM) capsule, a Chinese patent medicine, on oxidative stress-induced apoptosis of pericytes implicated with poly (ADP-ribose) polymerase (PARP) / glyceraldehyde 3-phosphate dehydrogenase (GAPDH) pathway. Methods Network pharmacology approach was performed to predict biofunction of components of SDMM capsule dissolved in plasma on DR. Both PARP1 and GAPDH were found involved in the hub network of protein-protein interaction (PPI) of potential targets and were found to take part in many bioprocesses, including responding to the regulation of reactive oxygen species (ROS) metabolic process, apoptotic signaling pathway, and response to oxygen levels through enrichment analysis. Therefore, in vitro research was carried out to validate the prediction. Human RMPs cultured with media containing 0.5 mM hydrogen oxide (H2O2) for 4 h was performed as an oxidative-damage model. Different concentrations of SDMM capsule, PARP1 inhibitor, PARP1 activation, and GAPDH inhibitor were used to intervene the oxidative-damage model with N-Acetyl-L-cysteine (NAC) as a contrast. Flow cytometry was performed to determine the apoptosis rate of cells and the expression of ROS. Cell counting kit 8 (CCK8) was used to determine the activity of pericytes. Moreover, nitric oxide (NO) concentration of cells supernatant and expression of endothelial nitric oxide synthase (eNOS), superoxide dismutase (SOD), B cell lymphoma 2 (BCL2), vascular endothelial growth factor (VEGF), endothelin 1 (ET1), PARP1, and GAPDH were tested through RT-qPCR, western blot (WB), or immunocytochemistry (ICC). Results Overproduction of ROS, high apoptotic rate, and attenuated activity of pericytes were observed after cells were incubated with media containing 0.5 mM H2O2. Moreover, downregulation of SOD, NO, BCL2, and GAPDH, and upregulation of VEGFA, ET1, and PARP1 were discovered after cells were exposed to 0.5 mM H2O2 in this study, which could be improved by PARP1 inhibitor and SDMM capsule in a dose-dependent way, whereas worsened by PARP1 activation and GAPDH inhibitor. Conclusions SDMM capsule may attenuate oxidative stress-induced apoptosis of pericytes through downregulating PARP expression and upregulating GAPDH expression.


2021 ◽  
Vol 22 (15) ◽  
pp. 8296
Author(s):  
Rüdiger Hardeland

Melatonin interacts in multiple ways with microglia, both directly and, via routes of crosstalk with astrocytes and neurons, indirectly. These effects of melatonin are of relevance in terms of antioxidative protection, not only concerning free-radical detoxification, but also in prevention of processes that cause, promote, or propagate oxidative stress and neurodegeneration, such as overexcitation, toxicological insults, viral and bacterial infections, and sterile inflammation of different grades. The immunological interplay in the CNS, with microglia playing a central role, is of high complexity and includes signaling toward endothelial cells and other leukocytes by cytokines, chemokines, nitric oxide, and eikosanoids. Melatonin interferes with these processes in multiple signaling routes and steps. In addition to canonical signal transduction by MT1 and MT2 melatonin receptors, secondary and tertiary signaling is of relevance and has to be considered, e.g., via the upregulation of sirtuins and the modulation of pro- and anti-inflammatory microRNAs. Many details concerning the modulation of macrophage functionality by melatonin are obviously also applicable to microglial cells. Of particular interest is the polarization toward M2 subtypes instead of M1, i.e., in favor of being anti-inflammatory at the expense of proinflammatory activities, which is well-documented in macrophages but also applies to microglia.


Sign in / Sign up

Export Citation Format

Share Document