Dataset Information

Elevated plasma 8-iso-prostaglandin F2? levels in human smokers originate primarily from enzymatic instead of non-enzymatic lipid peroxidation.

ABSTRACT: It is widely accepted that free radicals in tobacco smoke lead to oxidative stress and generate the popular lipid peroxidation biomarker 8-iso-prostaglandin F2? (8-iso-PGF2?). However, 8-iso-PGF2? can simultaneously be produced in vivo by the prostaglandin-endoperoxide synthases (PGHS) induced by inflammation. This inflammation-dependent mechanism has never been considered as a source of elevated 8-iso-PGF2? in tobacco smokers. The goal of this study is to quantify the distribution of chemical- and PGHS-dependent 8-iso-PGF2? formation in the plasma of tobacco smokers and non-smokers. The influences of gender and hormonal contraceptive use were accounted for. The distribution was determined by measuring the 8-iso-PGF2?/prostaglandin F2? (PGF2?) ratio. When comparing smokers (n = 28) against non-smokers (n = 30), there was a statistically significant increase in the 8-iso-PGF2? concentration. The source of this increased 8-iso-PGF2? was primarily from PGHS. When stratifying for gender, the increase in 8-iso-PGF2? in male smokers (n = 9) was primarily from PGHS. Interestingly, female smokers on hormonal contraceptives had increased 8-iso-PGF2? in both pathways, whereas those not on hormonal contraceptives did not have increased 8-iso-PGF2?. In conclusion, increased plasma 8-iso-PGF2? in tobacco smokers has complex origins, with PGHS-dependent formation as the primary source. Accounting for both pathways provides a definitive measurement of both oxidative stress and inflammation.

SUBMITTER: van 't Erve TJ

PROVIDER: S-EPMC5767525 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Elevated plasma 8-iso-prostaglandin F2α levels in human smokers originate primarily from enzymatic instead of non-enzymatic lipid peroxidation.

van 't Erve Thomas J TJ Lih Fred B FB Kadiiska Maria B MB Deterding Leesa J LJ Mason Ronald P RP

Free radical biology & medicine 20171121

It is widely accepted that free radicals in tobacco smoke lead to oxidative stress and generate the popular lipid peroxidation biomarker 8-iso-prostaglandin F2α (8-iso-PGF2α). However, 8-iso-PGF2α can simultaneously be produced in vivo by the prostaglandin-endoperoxide synthases (PGHS) induced by inflammation. This inflammation-dependent mechanism has never been considered as a source of elevated 8-iso-PGF2α in tobacco smokers. The goal of this study i ...[more]

PMID: 29162517

Similar Datasets

Project description:BACKGROUND:Lower socioeconomic status (SES) and psychosocial stress during pregnancy have been associated with adverse birth outcomes. While hypothalamic-pituitary-axis activation is thought to be the primary driver, oxidative stress may also be involved mechanistically. We used data from the Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) cohort (N=476) to examine associations between self-reported psychosocial stress measures, SES indicators, and urinary oxidative stress biomarker concentrations, hypothesizing that women with lower SES and increased psychosocial stress would have elevated oxidative stress biomarkers. METHODS:Maternal age, education, marital status, insurance status, alcohol use and smoking status were obtained via self-reported questionnaires and were used as indicators of SES. Perceived stress, depression, negative life experiences, neighborhood perceptions, and social support were self-reported in questionnaires administered during pregnancy. Responses were grouped into tertiles for analysis, where the highest tertile corresponded to highest level of psychosocial stress. Urinary concentrations of 8-iso-prostaglandin F2? (8-iso-PGF2?) and its primary metabolite were measured at three study visits (median 18, 24, 28 weeks gestation) and averaged to reflect oxidative stress across pregnancy. Linear models were used to examine associations between SES indicators, tertiles of psychosocial stress and oxidative stress biomarkers. RESULTS:Average levels of 8-iso-PGF2? and the 8-iso-PGF2? metabolite were higher among pregnant women who were younger, who had public compared to private insurance, and who were unemployed compared to employed. However, no associations were observed between psychosocial stress measures and biomarker concentrations in adjusted analyses. CONCLUSIONS:Psychosocial stress during pregnancy, as indicated by self-reported questionnaire measures, was not associated with biomarkers of oxidative stress in the PROTECT study. However, results suggest that these biomarkers are elevated among women of lower SES, which is typically associated with stress. Notably, compared to other populations, self-reported psychosocial stress measures were lower in PROTECT compared to other populations.

Project description:1. 8-Iso prostaglandin F2 alpha (8-iso PGF2 alpha) is one of a series of prostanoids formed independently of the cyclo-oxygenase pathway. It has been shown to be upregulated in many conditions of oxidant stress where its formation is induced by free radical-catalysed actions on arachidonic acid. As 8-iso PGF2 alpha is formed in vivo in diseases in which oxidant stress is high such as septic shock, we have assessed the relative potency and efficacy of this compound in pulmonary arteries from control and lipopolysaccharide (LPS)-treated rats. 2. Several studies have characterized the contractile actions of 8-iso PGF2 alpha on various smooth muscle preparations, but its potential dilator actions have not been addressed. Thus these studies examined both the contractile and dilator actions of 8-iso PGF2 alpha in rat pulmonary artery rings. The thromboxane mimetic U46619, PGE2 sodium nitroprusside (SNP) and acetyl choline (ACh) were used for comparison. Each prostanoid had to be dissolved in ethanol to a maximum concentration of 1 x 10-2 M. At high concentrations, ethanol directly contracted pulmonary vessels. We were therefore limited by the actions of the vehicle such that we were unable to add prostanoids at concentrations higher than 1 x 10-4 M. In some cases this meant that maximum responses were not achieved and in these cases the Emax and pD2 values are apparent estimates. 3. The following rank order of potency was obtained from contractile studies; U46619 > 8-iso PGF2 alpha > PGE2, each prostanoid producing concentration-dependent contractions (10(-10)-3 x 10(-4) M, 10(-9)-10(-4) M, 10(-8)-10(-4) M, respectively). As has been shown previously for other smooth muscle preparations, the thromboxane receptor (TP) antagonist ICI 192605, (1 x 10(-6), 1 x 10(-5) and 1 x 10(-4) M), inhibited the contractions of 8-iso PGF2 alpha in a concentration-dependent fashion. 4. The nitric oxide synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME; 1 x 10(-4) M), enhanced the contractile function of both 8-iso PGF2 alpha and PGE2, but had no effect on that caused by U46619. Similarly, L-NAME inhibited the dilator function of all agents tested except the exogenous nitric oxide (NO) donor SNP indicating that PGE2 and 8-iso PGF2 alpha like ACh, act through the release of NO. The specificity of the effects of L-NAME were confirmed in studies with the inactive enantiomer D-NAME (1 x 10(-4) M), which did not affect the contractile or the dilator actions of 8-iso PGF2 alpha. Furthermore, ICI 192605 enhanced the dilator actions of 8-iso PGF2 alpha, suggesting that the dilator component of 8-iso PGF2 alpha was achieved via activation of a non-TP receptor. 5. Isoprostanes may modulate vascular tone by a direct action on TP receptors to cause contraction and via a distinct receptor leading to the release of NO to cause dilation.

Dataset Information

Elevated plasma 8-iso-prostaglandin F2? levels in human smokers originate primarily from enzymatic instead of non-enzymatic lipid peroxidation.

Publications

Elevated plasma 8-iso-prostaglandin F<sub>2α</sub> levels in human smokers originate primarily from enzymatic instead of non-enzymatic lipid peroxidation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure