Estrogen diminishes postischemic hydroxyl radical production

1998 ◽  
Vol 274 (6) ◽  
pp. H1950-H1954 ◽  
Author(s):  
Nansie A. McHugh ◽  
Gary F. Merrill ◽  
Saul R. Powell
Keyword(s):  
Tissue Injury ◽  
Antioxidant Properties ◽  
Cardioprotective Effect ◽  
Oh Radicals ◽  
Acute Administration ◽  
Reperfusion Arrhythmias ◽  
Conjugated Equine Estrogen ◽  
Anesthetized Dogs ◽  
Reperfusion Of The Myocardium ◽  
Equine Estrogens

Reperfusion of blood flow to an ischemic myocardium is imperative to survival; ironically, it may also manifest several pathophysiological conditions. The most important of these are reperfusion arrhythmias and tissue injury and/or death. The mechanisms involved in reperfusion arrhythmias remain to be fully elucidated; however, increasing evidence indicates that reperfusion-induced arrhythmias are a free radical-mediated phenomenon. Acute administration of conjugated equine estrogen to dogs attenuates ischemia- and reperfusion-induced arrhythmias. The cardioprotective effect of estrogens in postmenopausal women is well documented, and recent studies suggest that estrogens possess strong antioxidant properties, with equine estrogens most potent. In this study we show that administration of conjugated equine estrogen to fully anesthetized dogs abolishes the burst of ⋅ OH radicals typically produced on reperfusion of the myocardium. This indicates that estrogen might attenuate reperfusion-induced ventricular arrhythmias by virtue of its antioxidant properties, suggesting a novel cardioprotective effect of the hormone.

Mechanisms of the Putative Cardioprotective Effect of Hexamethonium in Anesthetized Dogs Given a Large Dose of Bupivacaine

1994 ◽  
Vol 80 (3) ◽  
pp. 595-605 ◽  
Author(s):  
Jean E. de La Coussaye ◽  
Jean-Jacques Eledjam ◽  
Pascal Bruelle ◽  
Jean-Yves Lefrant ◽  
Bruno Bassoul ◽  
...  
Keyword(s):  
Large Dose ◽  
Cardioprotective Effect ◽  
Anesthetized Dogs

scholarly journals Inhibition of Digestive Enzymes, Antioxidant and Free Radical Scavenging Capacities of Stem Bark Extracts of Coula edulis Baill (Olacaceae)

2021 ◽  
Vol 10 (5) ◽  
pp. 1
Author(s):  
Eric Beyegue ◽  
Boris G. K. Azantsa ◽  
Angie M-A Mbong ◽  
Julius E. Oben
Keyword(s):  
Oxidative Stress ◽  
Free Radical ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Ethanolic Extract ◽  
Stem Bark ◽  
Alpha Amylase ◽  
In Vitro Assays ◽  
Oh Radicals

Prolonged hyperglycemia enhances oxidative stress. Bioactive compounds extracted possess antioxidant, anti-free radical potentials or the ability to reduce blood sugar levels. The objective of this study was to evaluate the antioxidant properties of extracts of stem bark of Coula edulis Baill., their abilities to trap free radicals and glucose, as well as their ability to inhibit α-amylase and invertase activities. In vitro assays were used to test the trapping capacity of extracts on DPPH, ABTS, NO, and OH radicals; to evaluate the antioxidant capacity, the activity of glycosylation and the capacity of inhibition of the activities of α-amylase and invertase were conducted. Also, phenolic, flavonoid and alkaloid contents of extracts were determined. Results showed that extracts of the stem bark of C. edulis have anti-radical properties. The extracts chelate DPPH, hydroxyl (OH), nitrite oxide (NO), ABTS radicals, and even glucose. The IC50 values varied depending on the nature of the extraction solvent. Ethanolic extract has the highest polyphenolic content (289.12 ± 30.31 µg catechin equivalent/g), flavonoids (1.12 ± 0.09 µg quercetin equivalent/g) and alkaloids (5.54 ± 0.59 µg quinin equivalent/g). The extracts also reduce invertase and α-amylase activities. C. edulis extracts present strong antioxidant potentials and can be used as a source of natural antioxidants for the prevention of oxidative stress and hyperglycemia.

Role of oxygen-derived free radicals in canine reperfusion arrhythmias

1995 ◽  
Vol 268 (1) ◽  
pp. H295-H300 ◽  
Author(s):  
D. E. Euler
Keyword(s):  
Free Radicals ◽  
Ventricular Fibrillation ◽  
Coronary Flow ◽  
Reperfusion Arrhythmias ◽  
Arterial Blood ◽  
Oxygen Derived Free Radicals ◽  
Shunt Occlusion ◽  
Anesthetized Dogs ◽  
Retrograde Coronary Flow

The role of oxygen-derived free radicals in reperfusion arrhythmias was investigated in open-chest anesthetized dogs. The left anterior descending coronary artery was cannulated and perfused by an arterial bypass shunt. Ischemia was produced for 15 min by shunt occlusion and retrograde diversion of collateral blood flow. Dogs (n = 12) were treated with saline, N-(2-mercaptopropionyl)glycine (50 mg/kg), deferoxamine (10 mg/kg), superoxide dismutase (15,000 U/kg) plus catalase (55,000 U/kg), or dimethylthiourea (500 mg/kg). All agents were infused intravenously for 1 h starting 30 min before occlusion and continuing for 5 min of reperfusion. There were no differences in mean arterial blood pressure, heart rate, antegrade coronary flow, retrograde coronary flow, or size of the risk region among the five treatment groups. None of the dogs developed ventricular fibrillation during occlusion, whereas 88% of the 60 dogs fibrillated upon reperfusion. The antioxidant interventions did not alter the incidence of reperfusion-induced ventricular fibrillation compared with the saline-treated controls. The results suggest that free radicals do not play a role in lethal canine reperfusion arrhythmias.

scholarly journals The Anti-Inflammatory Role of Bilirubin on “Two-Hit” Sepsis Animal Model

2020 ◽  
Vol 21 (22) ◽  
pp. 8650
Author(s):  
Duc Tin Tran ◽  
Yong Yeon Jeong ◽  
Jeong Min Kim ◽  
Hong Bum Bae ◽  
Sung Kuk Son ◽  
...  
Keyword(s):  
Animal Model ◽  
Inflammatory Cytokines ◽  
Tissue Injury ◽  
Antioxidant Properties ◽  
Cecal Ligation ◽  
Suppressor Cells ◽  
Inflammatory Cells ◽  
The Body ◽  
Sepsis Model ◽  
Anti Inflammatory

Introduction: Bilirubin is a product of the heme catabolism pathway, and it is excreted in bile and removed from the body through the urine. Bilirubin has potent antioxidant properties but also plays a role in anti-inflammation by protecting the body against endotoxin-induced lung inflammation, down-regulating the expression of adhesion molecules, and inhibiting the infiltration of inflammatory cells. Thus, bilirubin is a promising agent that could use in inflammation disease treatment. The application of bilirubin on the “two-hit” sepsis animal model has been, to date, unknown. Methods: we used lipopolysaccharide to induce initial insults in C57BL/6 mice. After 24 h, mice underwent cecal ligation and puncture to induce the “two-hit” sepsis model. Next, mice were administered 30 mg/kg bilirubin and we observed an improvement. Results: We observed that bilirubin inhibited the expression of pro-inflammatory cytokines, while the levels of anti-inflammatory cytokines were significantly augmented in the lung. Bilirubin improved the survival rate in the sepsis model. Furthermore, we suggest that bilirubin can modulate the accumulation of T-regulatory cells and myeloid-derived suppressor cells. Notably, bilirubin suppressed the activation and functions of T-cells. Conclusions: These results clarified that bilirubin might improve tissue injury in sepsis through anti-inflammatory mechanisms.

Pleiotropic roles of melatonin against oxidative stress mediated tissue injury in the gastrointestinal tract: An overview

2019 ◽  
Vol 2 (2) ◽  
pp. 158-184 ◽  
Author(s):  
Palash K Pal ◽  
Bharati Bhattacharjee ◽  
Aindrila Chattopadhyay ◽  
Debasish Bandyopadhyay
Keyword(s):  
Oxidative Stress ◽  
Molecular Mechanisms ◽  
Clinical Symptoms ◽  
Tissue Injury ◽  
Ischemia Reperfusion ◽  
Antioxidant Properties ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Gi Tract ◽  
Pathological Conditions

The excessive production of free radicals and/or reactive oxygen species (ROS) in gastrointestinal (GI) tract leads to oxidative damages in GI tissues with development of varied pathological conditions and clinical symptoms. Many endogenous as well as exogenous factors are involved in such pathogenesis, herein, focus was given to the factors of metal toxicity, non-steroidal anti-inflammatory drugs (NSAIDs), ischemia-reperfusion, consumption of high fat diet and alcohol, and different pathological conditions and diseases. Since ROS is more or less involved in the GI damages caused by these factors, therefore attempts have been made to develop appropriate therapeutic agents that possess antioxidant properties. Being a potent antioxidant and free radical scavenger, melatonin was suggested as a potent therapeutic answer to these GI damages. The discovery of different binding sites and receptors of melatonin in the GI tissues further proves its local actions to protect these tissues from oxidative stress.  In the review, we attempt to try our best to summarize the current developments regarding the GI injuries caused by oxidative stress and the potential beneficial effects of melatonin on these injuries. The important molecular mechanisms associated with these changes were also highlighted in the discussion. We hope that this review will provide valuable information to consider melatonin as a suitable molecule used for GI tract protection.

Synthesis, Spectroscopic Characterization and Biological Evaluation of 1-(4'-Hydroxybenzamido)-Imine-1,2,3,4-Tetrahydrocarbazole Derivatives

2017 ◽  
Vol 6 (1) ◽  
pp. 30-40 ◽  
Author(s):  
Munusamy Saravanabhavan ◽  
Ambason Franklin Ebenazer ◽  
Venkatesan Murugesan ◽  
Marimuthu Sekar
Keyword(s):  
Antioxidant Properties ◽  
Spectroscopic Characterization ◽  
Spectroscopic Studies ◽  
Docking Studies ◽  
Biological Evaluation ◽  
Assay Method ◽  
Oh Radicals ◽  
Synthetic Approach ◽  
Anticancer Activities

A facile synthetic approach towards 1-(4'-hydroxybenzamido)-imine-1,2,3,4-tetrahydrocarbazole derivatives 3a–g was reported via reaction of 1-oxo-1,2,3,4-tetrahydrocarbazoles 1a–g, with p-hydroxybenzhydrazide in ethanol in the presence of sufficient amount of acetic acid. The structure of all the compounds was confirmed by spectroscopic studies. The antioxidant properties of all the derivatives have also been checked against DPPH and OH radicals. Further, in vitro anticancer activities of all the synthesized compounds were investigated by MTT assay method. All the prepared analogues exhibited considerable anticancer properties especially, 3e and 3f which reveled the best anticancer activity among all the test compounds. Additionally, we carried out molecular docking studies using the protein kinase CK2 inhibitors. In all the biological assays, halogen substituted carbazole derivatives showed enhanced activities than the other derivatives.

scholarly journals Influence of Drying Temperature on Phenolic Acids Composition and Antioxidant Activity of Sprouts and Leaves of White and Red Quinoa

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Urszula Złotek ◽  
Urszula Gawlik-Dziki ◽  
Dariusz Dziki ◽  
Michał Świeca ◽  
Renata Nowak ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Phenolic Compounds ◽  
Hydroxyl Radicals ◽  
Phenolic Acids ◽  
Total Phenolics ◽  
Antioxidant Properties ◽  
Chenopodium Quinoa ◽  
Reducing Power ◽  
Oh Radicals ◽  
Drying Temperature

The aim of this study was to evaluate the influence of drying temperature on the phenolic acids profile and antioxidant activity of sprouts and leaves red and white Chenopodium quinoa (RQ and WQ, respectively). Four-day sprouts and leaves dried at 30, 45, and 60°C were tested. All sprouts contained significant amounts of phenolic compounds; however, higher content was determined in the RQ sprouts. Phenolic compounds from WQ sprouts seem to be thermostable in the studied temperature range, whereas total phenolics content in RQ sprouts decreased significantly after drying in the 60°C. Content of vanillic and p-coumaric acids did not differ significantly between sprouts dried at the same conditions; however, their level decreased in the high temperature. Irrespective of the drying temperature, higher activity against ABTS free radicals and reducing power was observed in the case of RQ sprouts extracts. Sprouts dried at 30°C had a higher ability to scavenge hydroxyl radicals. RQ sprouts were characterized by about two times higher antioxidant activity regardless of the method used. No significant differences between total phenolics (TPC) and flavonoids content in RQ and LQ leaves were found. In the both cases, decrease of TPC was observed after drying in the highest temperature. The leaves do not differ too much in terms of the phenolic acids profile, whereas the differentiating factor is thermal processing. Leaves of both quinoa contained thermostable compounds able to scavenge hydroxyl radicals. Reducing power and ability to scavenge OH radicals were correlated with all components of quinoa sprouts which suggest synergism between them and does not indicate the key role of a particular compound in creating antioxidant capacity. Germination and subsequent oven-drying at 30°C of quinoa seeds significantly increased the antioxidant properties compared with raw seeds. Also, in the case of leaves, the best results were obtained after drying at 30°C.

Comparison of renal excretion of rubidium and potassium

1959 ◽  
Vol 197 (6) ◽  
pp. 1297-1302 ◽  
Author(s):  
Arthur S. Kunin ◽  
Earl H. Dearborn ◽  
Belton A. Burrows ◽  
Arnold S. Relman
Keyword(s):  
Glomerular Filtration Rate ◽  
Plasma Level ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
Renal Excretion ◽  
Acute Administration ◽  
Rubidium Chloride ◽  
Anesthetized Dogs ◽  
Renal Clearances

The simultaneous renal clearances of rubidium and potassium were studied during the infusion of solutions of rubidium chloride into intact anesthetized dogs. The effects of prior loading with potassium were studied, as were also the responses to acute administration of acetazoleamide and meralluride. It was observed that the clearance of rubidium was usually slightly less than that of potassium and tended under most circumstances to vary in parallel with it. During infusion of RbCl the clearance of rubidium was usually less than the glomerular filtration rate and was independent of plasma level when the latter was varied from 1.0 to 5.0 mEq/l. However, net secretion of rubidium, as well as of potassium, could be demonstrated during periods of reduced filtration rate following administration of acetazoleamide. In the present experiments there was no evidence of interionic competition, but this possibility has not been critically tested. It is concluded that rubidium and potassium are probably handled by similar, if not identical, tubular mechanisms. The secretion of rubidium appears to be slower than that of potassium.

scholarly journals Efficacy of quercetin derivatives in prevention of ulcerative colitis in rats

2013 ◽  
Vol 6 (1) ◽  
pp. 9-12 ◽  
Author(s):  
Ruzena Sotnikova ◽  
Viera Nosalova ◽  
Jana Navarova
Keyword(s):  
Ulcerative Colitis ◽  
Acetic Acid ◽  
Intestinal Inflammation ◽  
Tissue Injury ◽  
Reductase Activity ◽  
Antioxidant Properties ◽  
Control Group ◽  
Wall Thickening ◽  
Quercetin Derivatives

Abstract Reactive oxygen species has been implicated to contribute significantly to tissue injury associated with ulcerative colitis. Thus compounds with antioxidant properties could be potential therapeutic agents in this disease. Flavonoid compounds are known to possess antioxidative and antiinflammatory properties. Two derivatives of the flavonoid quercetin (Q), chloronaphthoquinone quercetin (CNC) and monochloropivaloyl quercetin (MCP), showed improved antioxidant properties and moreover, they efficiently inhibited aldose reductase activity in vitro. The aim of the work was to test the potential efficacy of quercetin and these synthetic derivatives in vivo in prevention of intestinal inflammation during ulcerative colitis in rats. Colitis was induced by intracolonic administration of acetic acid (4% solution). The control group received the same volume of saline. The vehicle dimethyl sulfoxide (DMSO) and the drugs Q, CNC or MCP were administered orally two hours and then one hour before the acetic acid or saline instillation. After 48 hours, the animals were sacrificed and the colon was weighed, measured and scored for visible damage. Acetic acid triggered an intense inflammatory response of the colon, characterised by haemorrhage, ulceration and bowel wall thickening. From the drugs tested, only CNC (2 × 50 mg/kg) effectively depressed inflammatory damage of the colon. The mechanism of this beneficial effect remains to be elucidated.

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