Search results for "Oxidative Damage"

The effect of olive oil polyphenols on antibodies against oxidized LDL. A randomized clinical trial

2010

summary Background & aim: Oxidized LDL (oxLDL) is a highly immunogenic particle that plays a key role in the development of atherosclerosis. Some data suggest a protective role of OxLDL autoantibodies (OLAB) in atherosclerosis. Our aim was to assess the effect of olive oil polyphenols on the immunogenicity of oxLDL to autoantibody generation. Methods: In a crossover, controlled trial, 200 healthy men were randomly assigned to 3-week sequences of 25 mL/day of 3 olive oils with high (366 mg/kg), medium (164 mg/kg), and low (2.7 mg/kg) phenolic content. Results: Plasma OLAB concentration was inversely associated with oxLDL (p < 0.001). Olive oil phenolic content increased OLAB generation, with…

Assessment of oxidative damage to proteins and DNA in urine of newborn infants by a validated UPLC-MS/MS approach

2014

The assessment of oxidative stress is highly relevant in clinical Perinatology as it is associated to adverse outcomes in newborn infants. This study summarizes results from the validation of an Ultra Performance Liquid Chromatography-tandem Mass Spectrometry (UPLC-MS/MS) method for the simultaneous quantification of the urinary concentrations of a set of endogenous biomarkers, capable to provide a valid snapshot of the oxidative stress status applicable in human clinical trials, especially in the field of Perinatology. The set of analytes included are phenylalanine (Phe), para-tyrosine (p-Tyr), ortho-tyrosine (o-Tyr), meta-tyrosine (m-Tyr), 3-NO2-tyrosine (3NO(2)-Tyr), 3-Cl-tyrosine (3Cl-T…

An oxidatively damaged G-quadruplex/hemin DNAzyme.

2020

International audience; Oxidative damage of guanine to 8-oxoguanine triggers a partial and variable loss of G-quadruplex/hemin DNAzyme activity and provides clues to the mechanistic origins of DNAzyme deactivation, which originates from an interplay between decreased G-quadruplex stability, lower hemin affinity and a modification of the nature of hemin binding sites.

An anti-interleukin-2 receptor drug attenuates T- helper 1 lymphocytes-mediated inflammation in an acute model of endotoxin-induced uveitis.

2014

The aim of the present study was to evaluate the anti-inflammatory efficacy of Daclizumab, an anti-interleukin-2 receptor drug, in an experimental uveitis model upon a subcutaneous injection of lipopolysaccharide into Lewis rats, a valuable model for ocular acute inflammatory processes. The integrity of the blood-aqueous barrier was assessed 24 h after endotoxin-induced uveitis by evaluating two parameters: cell count and protein concentration in aqueous humors. The histopathology of all the ocular structures (cornea, lens, sclera, choroid, retina, uvea, and anterior and posterior chambers) was also considered. Enzyme-linked immunosorbent assays of the aqueous humor samples were performed t…

Dose-dependent metabolic disposition of hydroxytyrosol and formation of mercapturates in rats

2013

Hydroxytyrosol (HT), one of the major polyphenols present in olive oil, is known to possess a high antioxidant capacity. The aim of the present study was to investigate dose dependent (0, 1, 10 and 100 mg/kg) alterations in the metabolism of HT in rats since it has been reported that metabolites may contribute to biological effects. Special attention was paid to the activation of the semiquinone quinone oxidative cycle and the formation of adducts with potential deleterious effects. Thus, we developed a novel analytical methodology to monitor the in vivo formation of the HT mercapturate, N-acetyl-5-S-cysteinyl-hydroxytyrosol in urine samples. Biomarkers of hepatic and renal toxicity were ev…

Glucocorticoid receptor knockdown decreases the antioxidant protection of B16 melanoma cells: an endocrine system-related mechanism that compromises …

2014

We previously reported an interorgan system in which stress-related hormones (corticosterone and noradrenaline), interleukin-6, and glutathione (GSH) coordinately regulate metastatic growth of highly aggressive B16-F10 melanoma cells. Corticosterone, at levels measured in tumor-bearing mice, also induces apoptotic cell death in metastatic cells with low GSH content. In the present study we explored the potential role of glucocorticoids in the regulation of metastatic cell death/survival during the early stages of organ invasion. Glucocorticoid receptor (GCR) knockdown decreased the expression and activity of γ-glutamylcysteine synthetase (γ-GCS), the rate-limiting step in GSH synthesis, in …

Oxidative damage of DNA: Repair and implications

2006

Exercise as a calorie restriction mimetic. Implications for the treatment of age associated frailty

2018

The free radical theory of aging has provided a theoretical framework for an enormous amount of work leading to advances in our understanding of aging. A critical blow to the free radical theory of aging came from epidemiological studies showing that antioxidant supplementation did not lower the incidence of age-associated diseases. However, work from many laboratories supports the theory, for instance showing that overexpression of antioxidant enzymes results in increases not only in life-span but also in health-span. Improving healthy aging means delaying disability. Disability is often preceded by a state characterized by reduced capacity to respond to stressors, caused by a decline in f…

Synthesis and biological evaluation of structural variants of carbazoquinocin C

2003

Some new structural variants of the alkaloid carbazoquinocin C were synthesized in a few steps with good to excellent yields. The key step comprises a cyclisation reaction of appropriate 2-vinylindoles with oxalyl chloride. The carbazole-3,4-quinones are able to trap oxygen-centred radicals. In some biological/biochemical assays some of these compounds exhibit extraordinary results including inhibition of cyclooxygenase-1 and 5-lipoxygenase in the μM-range. Moreover some of the carbazoquinocin C-variants inhibit significant oxidative damage of cellular DNA in nM-range.

Solvent-dependent hypsochromic shift in the imidazole based complex [Cu(µ2-SO4)(Im)4] and ameliorative effects on breast cancer-induced bone metastas…

2023

A sulfate-bridged complex [Cu(µ2-SO4)(Im)4] (1) was prepared and structurally characterized, where Im: imidazole. The X-ray structure analysis reveals that 1 crystallizes in the monoclinic system with space group C2/c. The octahedral coordination around the metal center is made up of four distinct imine nitrogen atoms in the equatorial plane, and two sulfate oxygen atoms occupying the axial sites. The covalent linkage between metals via the sulfate group, forming infinite 1D zigzag chains, ensures the entanglement of the structure. These chains, in turn, are further assembled into a 2D network through N-H...O hydrogen bonding. Thermal analyses underline the high thermal stability of our com…