Activity of thiols as singlet molecular oxygen quenchers

Devasagayam, T.P.A.; Sundquist, Alfred R.; Mascio, Paolo Di; Kaiser, S.; Sies, H.

doi:10.1016/1011-1344(91)80008-6

Cited by 159 publications

(95 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The scavengers used were as follows: BHA and GSH, free radical scavengers; 21 NaN3, singlet oxygen scavenger; 21,22 and D-mannitol, a superoxide scavenger. 23 The addition of scavengers to the Trp solution produced a protective effect on photodegradation (Fig.…”

Section: Ros-mediated Photodegradation Of Trpmentioning

confidence: 99%

Photoreactivity of Amino Acids: Tryptophan-induced Photochemical Events via Reactive Oxygen Species Generation

2007

View full text Add to dashboard Cite

ChemicalsEssential amino acids, quinine, sodium dodecyl sulfate (SDS), and several ROS scavengers, such as butylated hydroxyanisole (BHA), reduced gluthatione (GSH), sodium azide (NaN3), and Tryptophan (Trp), an aromatic amino acid, is a constituent of peptides/proteins and is also a precursor of serotonin, kynurenine derivatives, and nicotinamide adenine dinucleotides. There have been a number of reports on photochemical reactions involving peptides/proteins which contain Trp that showed significant photodegradation, dimerization, and photoionization. The photochemical properties of Trp have not been fully elucidated, and this would provide novel insight into the handling of Trp-containing peptides/proteins. Consequently, we have been trying to evaluate the photochemical properties of Trp, as well as other essential amino acids, focusing on their photosensitivity, photodegradation, and their ability to induce lipid peroxidation. Among all the essential amino acids tested, Trp exhibited the maximal level of superoxide anion generation under 18 h of light exposure (30000 lux). UV spectral analysis of Trp suggested the absorbability of UVA/B light, and exposure of Trp, in both solid and solution states, to UVA/B light resulted in significant photodegradation (t0.5: 18 h) and gradual color changes. In addition, photoirradiated Trp generated lipoperoxidant, a causative agent of photoirritation, and this might be associated with ROS generation.

show abstract

Section: Ros-mediated Photodegradation Of Trpmentioning

confidence: 99%

Photoreactivity of Amino Acids: Tryptophan-induced Photochemical Events via Reactive Oxygen Species Generation

2007

View full text Add to dashboard Cite

show abstract

“…14 Diallyldisulfide (DADS), a metabolite of allicin, includes redoxactive sulfhydryl (SH)-or disulfide (-S-S)-groups which have already been proven to act as radical scavengers. 47 Aged garlic extract and diallyl polysulfides inhibit the formation of TBA-reactive substances and fluorescent substances induced by iron-ascorbic acid in isolated liver microsomal membranes, indicating the protection against lipid peroxidation. 37 Alliin scavenges the hydroxyl radical (.OH) and garlic powder scavenges both .OH and 1,1-diphenyl-2-picrylhydrazyl radicals.…”

Section: Discussionmentioning

confidence: 99%

Garlic Extract Ameliorates Renal and Cardiopulmonary Injury in the Rats with Chronic Renal Failure

et al. 2011

View full text Add to dashboard Cite

Chronic renal failure (CRF) is associated with oxidative stress that promotes production of reactive oxygen species and cytokine release. We aimed to investigate the possible protective and antioxidant effects of aqueous garlic extract (AGE) in a rat model of CRF. Male Sprague-Dawley rats were randomly assigned as either CRF group with 5/6 reduction in the renal mass or sham-operated control group. CRF group received either saline or AGE (250 mg/kg/day/1 mL) orally for 3 weeks. At the end of the 3 weeks, rats were decapitated and trunk blood was collected. Creatinine, blood urea nitrogen (BUN) and lactate dehydrogenase (LDH) activity, and TNF-α and IL-1β levels were measured in the serum samples, while malondialdehyde (MDA), glutathione (GSH) levels, and myeloperoxidase (MPO) activity were determined in the kidney, lung, and heart samples. CRF caused significant decreases in tissue GSH, which were accompanied with significant increases in MDA levels and MPO activities, while the circulating levels of the LDH activity, creatinine, BUN, TNF-α, and IL-1β were elevated. AGE treatment alleviated CRF-induced oxidative changes in the injured tissues, while CRF-induced elevations in the blood levels of the pro-inflammatory cytokines and LDH were reduced. In conclusion, CRF-induced oxidative tissue injury occurs via the activation of pro-inflammatory mediators and by neutrophil infiltration into tissues and that the protective effects of garlic on CRF-induced injury can be attributed to its ability to inhibit neutrophil infiltration and pro-inflammatory mediators. These findings suggest that garlic, as a supplementary to diet, may have a potential therapeutic use in delimitating the systemic oxidant effects of CRF on remote organs.

show abstract

“…For the antioxidant function it is important that it serves as a substrate for dehydroascorbate reductase. GSH is able to react directly with ROS including H 2 O 2 (Dalton et al, 1986), hydroxyl radical (Smirnoff & Cumbes, 1989) and even 1 O 2 (Devasagayam et al, 1991). Chloroplasts also contain phospholipid hydroperoxide-scavenging glutathione peroxidase (Eshdat et al, 1997) that may be involved in the reduction of lipid peroxide of thylakoid membranes to its alcohol, suppressing the chain oxidation of thylakoid phospholipids.…”

Section: Stromal Defense Systemmentioning

confidence: 99%