scholarly journals Vitamin E Prevents Cold Wrap Restraint Stress-Induced Intestinal Fluid Transport Alterations in Rats

1994 ◽  
Vol 8 (7) ◽  
pp. 417-421 ◽  
Author(s):  
Scott Burdick ◽  
Ningren Cui ◽  
Lonnie R Empey ◽  
Richard N Fedorak
Keyword(s):  
Free Radical ◽  
Vitamin E ◽  
Restraint Stress ◽  
Fluid Transport ◽  
Radical Scavenging ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Intestinal Fluid ◽  
Fluid Absorption

Psychological stress may alter gastrointestinal absorptive function by increasing the quantity of intestinal free radicals or by lowering endogenous intestinal free radical scavenging capacity. Vitamin E has been shown to be a potent endogenous antioxidant and free radical scavenger under both physiological and pathological conditions. The purpose of this study was to determine whether cold wrap restraint stress altered in vivo intestinal fluid absorption in rats, and whether vitamin E administration prior to the induction of cold wrap restraint stress could prevent such changes in intestinal secretion. Jejunal, ileal and colonic fluid and electrolyte transport rates were measured in vivo using an isolated loop technique. Cold wrap restraint stress reduced in vivo fluid absorption in the ileum and colon, but not in the jejunum. Administration of vitamin E prior to the cold wrap restraint stress procedure completely prevented this alteration of ileal and colonic fluid absorption.

scholarly journals Free Radical–Mediated Cell Damage After Experimental Status Epilepticus in Hippocampal Slice Cultures

2002 ◽  
Vol 88 (6) ◽  
pp. 2909-2918 ◽  
Author(s):  
Richard Kovács ◽  
Sebastian Schuchmann ◽  
Siegrun Gabriel ◽  
Oliver Kann ◽  
Julianna Kardos ◽  
...  
Keyword(s):  
Free Radicals ◽  
Status Epilepticus ◽  
Free Radical ◽  
Hippocampal Slice ◽  
Cell Damage ◽  
Radical Scavenging ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Mitochondrial Depolarization ◽  
Hippocampal Slice Cultures

Generation of free radicals may have a key role in the nerve cell damage induced by prolonged or frequently recurring convulsions (status epilepticus). Mitochondrial function may also be altered due to production of free radicals during seizures. We therefore studied changes in field potentials (fp) together with measurements of extracellular, intracellular, and intramitochondrial calcium concentration ([Ca2+]e, [Ca2+]i, and [Ca2+]m, respectively), mitochondrial membrane potential (ΔΨ), NAD(P)H auto-fluorescence, and dihydroethidium (HEt) fluorescence in hippocampal slice cultures by means of simultaneous electrophysiological and microfluorimetric measurements. As reported previously, each seizure-like event (SLE) resulted in mitochondrial depolarization associated with a delayed rise in oxidation of HEt to ethidum, presumably indicating ROS production. We show here that repeated SLEs led to a decline in intracellular and intramitochondrial Ca2+ signals despite unaltered Ca2+ influx. Also, mitochondrial depolarization and the NAD(P)H signal became smaller during recurring SLEs. By contrast, the ethidium fluorescence rises remained constant or even increased from SLE to SLE. After about 15 SLEs, activity changed to continuous afterdischarges with steady depolarization of mitochondrial membranes. Staining with a cell death marker, propidium iodide, indicated widespread cell damage after 2 h of recurring SLEs. The free radical scavenger, α-tocopherol, protected the slice cultures against this damage and also reduced the ongoing impairment of NAD(P)H production. These findings suggest involvement of reactive oxygen species (ROS) of mitochondrial origin in the epileptic cell damage and that free radical scavenging may prevent status epilepticus–induced cell loss.

scholarly journals Hydroxyl radical induced structural changes of collagen

2007 ◽  
Vol 21 (2) ◽  
pp. 91-103 ◽  
Author(s):  
Helan Xiao ◽  
Guoping Cai ◽  
Mingyao Liu
Keyword(s):  
Free Radical ◽  
Hydroxyl Radicals ◽  
Structural Changes ◽  
Type I Collagen ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Type I ◽  
Dependent Manner ◽  
First Time

Extracellular matrix (ECM) plays an important role in cell differentiation, growth, migration and apoptosis. Collagen is the most abundant protein familyin vivo, but its function has still not been clearly defined yet. Reactive oxygen species (ROS) have a central role in oxidative cell stress. Electron spin resonance (ESR) spectroscopy indicates that type I collagen could uniquely scavenge hydroxyl radicals in dose- and time-dependent manner; whereas BSA and gelatin (a denatured collagen) have no such an effect. However, the mechanism by which type I collagen scavenges hydroxyl radicals is different from that of GSH, a well-known free radical scavenger. Using a new method, two-dimensional FTIR correlation analysis, for the first time, we show that the order of functional group changes of type I collagen in this process is amide I earlier than amide II than amide III than –CH– thanν(C=O). The results indicates that the structure of the main chain of collagen changed first, followed by more residue groupν(C=O) exposed to hydroxyl radicals. The reaction with the carbonyl group in collagen causes the hydroxyl free radicals to be scavenged. Therefore, ECM can effectively scavenge ROS under normal physiological conditions. When the proteins of ECM were denatured in the same way as gelatin, they lost their function as a free radical scavenger. All of these results provide new insight into therapy or prevention of oxidative stress, apoptosis and ageing.

Ceria-Zirconia Antioxidant Nanoparticles Attenuate Hypoxia-Induced Acute Kidney Injury by Restoring Autophagy Flux and Alleviating Mitochondrial Damage

2020 ◽  
Vol 16 (7) ◽  
pp. 1144-1159
Author(s):  
Sang-Eun Hong ◽  
Jong Hun An ◽  
Seong-Lan Yu ◽  
Jaeku Kang ◽  
Chang Gyo Park ◽  
...  
Keyword(s):  
Acute Kidney Injury ◽  
Free Radical ◽  
Antioxidant Activities ◽  
Kidney Injury ◽  
Mitochondrial Damage ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Autophagy Flux ◽  
Novel Approach

Oxidative stress is one of the principal causes of hypoxia-induced kidney injury. The ceria nanoparticle (CNP) is known to exhibit free radical scavenger and catalytic activities. When zirconia is attached to CNPs (CZNPs), the ceria atom tends to remain in a Ce3+ form and its efficacy as a free radical scavenger thus increases. We determined the effectiveness of CNP and CZNP antioxidant activities against hypoxia-induced acute kidney injury (AKI) and observed that these nanoparticles suppress the apoptosis of hypoxic HK-2 cells by restoring autophagy flux and alleviating mitochondrial damage. In vivo experiments revealed that CZNPs effectively attenuate hypoxia-induced AKI by preserving renal structures and glomerulus function. These nanoparticles can successfully diffuse into HK-2 cells and effectively counteract reactive oxygen species (ROS) to block hypoxia-induced AKI. This suggests that these particles represent a novel approach to controlling this condition.

Arjunic Acid, a Strong Free Radical Scavenger from Terminalia arjuna

2008 ◽  
Vol 36 (01) ◽  
pp. 197-207 ◽  
Author(s):  
Fang-Yun Sun ◽  
Xiu-Ping Chen ◽  
Jin-Hua Wang ◽  
Hai-Lin Qin ◽  
Su-Rong Yang ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Lipid Peroxidation ◽  
Ascorbic Acid ◽  
Free Radical ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Dpph Method ◽  
Significant Difference

This study was designed to investigate the antioxidant and free radical scavenging capacities of arjunic acid, an aglycone obtained from the fruit of medicine Terminalia Fruit. Liver microsomes, mitochondria, and red blood cells (RBCs) were prepared from Wistar rats. The antioxidant capacity was determined by the inhibitory effect on lipid peroxidation, hydrogen peroxide induced RBCs hemolysis, and RBCs autoxidative hemolysis. The free radical scavenging activity was tested by DPPH method and 2′,7′-dichlorodihydrofluoresc in diacetate (DCFH2-DA) assay. Ascorbic acid was chosen as the positive controls. Results showed that arjunic acid was a strong antioxidant and a free radical scavenger, more potent than ascorbic acid, in microsomes lipid peroxidation, DPPH, hydrogen peroxide induced RBCs hemolysis, and (DCFH2-DA) assay (p < 0.05). However, no significant difference was observed in the RBCs autoxidative hemolysis assay (p > 0.05).

A Novel Free Radical Scavenger, Edarabone, Protects Against Cisplatin-Induced Acute Renal Damage in Vitro and in Vivo

2003 ◽  
Vol 305 (3) ◽  
pp. 1183-1190 ◽  
Author(s):  
Minoru Satoh ◽  
Naoki Kashihara ◽  
Sohachi Fujimoto ◽  
Hideyuki Horike ◽  
Takehiko Tokura ◽  
...  
Keyword(s):  
Free Radical ◽  
Renal Damage ◽  
Free Radical Scavenger ◽  
Radical Scavenger

DPPH Free Radical Scavenger Components from the Fruits of Alpinia rafflesiana Wall. ex. Bak. (Zingiberaceae)

2004 ◽  
Vol 59 (11-12) ◽  
pp. 811-815 ◽  
Author(s):  
Habsah Mohamad ◽  
Faridah Abas ◽  
Dharma Permana ◽  
Nordin H. Lajis ◽  
Abdul Manaf Ali ◽  
...  
Keyword(s):  
Free Radical ◽  
Methanol Extract ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Scavenging Activity ◽  
Colorimetric Analysis ◽  
Natural Sources

The methanol extract of the dried ripe fruits of Alpinia rafflesiana was investigated for its DPPH free radical scavenger constituents. 2′,3′,4′,6′-Tetrahydroxychalcone (7), which has never been isolated from natural sources was found to be most active as a DPPH free radical scavenger with the IC50 value of 55 μᴍ. Other known compounds isolated from this species include 5,6-dehydrokawain (1), flavokawin B (2), 1,7-diphenyl-5-hydroxy-6-hepten-3-one (3), (-)-pinocembrin (4), cardamonin (5) and (-)-pinostrobin (6). The DPPH free radical scavenger compounds were detected using TLC autographic analysis. The percentage inhibition of DPPH free radical scavenging activity was measured on isolates (5-7) using colorimetric analysis.

scholarly journals Ilex khasiana - The silent holly species of Aquifoliaceae on its pharmacognostical importance as a free radical scavenger and antibacterial agent

2020 ◽  
Vol 11 (2) ◽  
pp. 2438-2444
Author(s):  
Charles Lalnunfela ◽  
Lalremsanga H.T. ◽  
Lalhriatpuii T.C. ◽  
Lalthanpuii P.B. ◽  
Kholhring Lalchhandama
Keyword(s):  
Free Radical ◽  
Medicinal Plant ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Northeast India ◽  
Free Radical Scavenger ◽  
Butylated Hydroxytoluene ◽  
Radical Scavenger ◽  
Endangered Medicinal Plant ◽  
Rare And Endangered

Ilex khasiana is a rare and endangered medicinal plant endemic to northeast India. Remaining largely unexplored,it is purported to have a range of medicinal values and may soon join the medicinal plant hall of fame.Extracts of the leaves were prepared using solvents of increasing polarity, namelypetroleum ether (IKP), chloroform (IKC) and methanol (IKM).The preliminary phytochemical screening indicated the presence of alkaloids, phytosterols, triterpenoids, saponins, reducing sugars, glycosides and carbohydrates. Free radical-scavenging activity was assessed using2,2-diphenyl-1-picrylhydrazyl(DPPH). IKC exhibited the highest activity with an IC50 of 17.22 ± 1.87, followed by IKM with an IC50 of 26.93 ± 5.14 and IKP with an IC50 of 37.16 ± 5.11. Butylated hydroxytoluene (BHT)was used as the standard DPPH scavenger and showed an IC50 of 8.31 ±0.72. IKM and IKC also showed positive antibacterial activity againstGram-negative bacteria such asEscherichia coli, Pseudomonas aeruginosa, andKlebsiella pneumoniae, and a Gram-positive bacteriaBacillus subtilis. IKP did not indicate any inhibition against the selected bacteria. Our findings substantiate the basis for further investigations on the medicinal potentials of the plant.  

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