We have previously shown that medroxyprogesterone acetate (MPA), either alone or combined with conjugated equine estrogens (CEE), significantly decreased insulin sensitivity (SI), compared with both untreated controls and those treated with CEE alone. The purpose of this study was to determine the effects of estradiol (E2), with and without nomegestrol acetate (NA; a potent progestin that lacks...

F2-isoprostanes are isomers of the prostaglandin PGF2alpha. At least one compound of this group, 8-epi-PGF2alpha, exhibits biological activity, and therefore special interest is focused on the mechanism of isoprostane formation: enzyme catalyzed or radical mediated. We analyzed the formation of isoprostanes in vitro and in vivo. In both systems, purified cyclooxygenase isoenzymes and cell model...

F2-isoprostanes (F2-IsoPs) are a gold marker of lipid peroxidation in vivo, whereas F4-neuroprostanes (F4-NPs) measured in cerebrospinal fluid (CSF) or brain tissue selectively indicate neuronal oxidative damage. Gas chromatography/negative-ion chemical-ionization mass spectrometry (GC/NICI-MS) is the most sensitive and robust method for quantifying these compounds, which is essential for CSF s...

The tea catechin EGCG has been postulated to provide health benefits in humans, to some extent, as an antioxidant. The dose-response effect of dietary EGCG (0, 30, 60, or 120 mg/kg diet) was tested in rats under high versus low oxidative stress conditions that were created by feeding diets adequate in vitamin E and Se (Lox), or deficient in both (Hox) for six weeks. Effects on growth, quinone r...

BACKGROUND Cardiovascular disease causes morbidity and mortality in chronic kidney disease. Increased formation of oxygen-derived radicals can accelerate the development of atherosclerosis. Several studies have shown an imbalance in antioxidant activity, resulting in high oxidative stress and lipid peroxidation, in subjects undergoing hemodialysis. METHODS Eighty-nine subjects with chronic ki...

We sought to determine whether motor and cognitive deficits associated with cassava (food) cyanogenic poisoning were associated with high concentrations of F2-isoprostanes, well-established indicators of oxidative damage. Concentrations of serum F2-isoprostanes were quantified by LC-MS/MS and anchored to measures of motor proficiency and cognitive performance, which were respectively assessed t...

To determine if 6 weeks of supplementation with vitamins E and C could alleviate exercise-induced lipid peroxidation and inflammation, we studied 22 runners during a 50 km ultramarathon. Subjects were randomly assigned to one of two groups: (1) placebos (PL) or (2) antioxidants (AO: 1000 mg vitamin C and 300 mg RRR-alpha-tocopheryl acetate). Blood samples were obtained prior to supplementation ...

Oxidative stress as classified by F2-Isoprostanes (F2-IsoPs) in Human Disease: Grab the Low-Hanging Fruit – The utility of F2-IsoPs as a biomarker of oxidative injury in human disease is complex. Careful consideration of the formation, metabolism, and measurement of this biomarker is imperative in the design of clinical trials. Conditions with significantly elevated levels of F2-IsoPs are ideal...