8isoPGF2alpha and alpha-tocopheronolactone as biomarkers of oxidative stress in sepsis

Sepsis is a state of severe illness caused by overwhelming infection of the blood stream by toxin producing bacteria. Oxidative stress has been indicated as an effect of the illness and not in its aetiology. 8isoPGp2α, is the most highly reliable and commonly used biomarker of oxidative stress in normal and diseased state individuals. It has also been suggested that metabolites of vitamin E such as α-Tocopheronolactone, may serve as an indicator of invivo oxidative stress. The aim of the current study was to re-establish and validate the methods using GC/MS for the analysis of 8isoPGF2α and vitamin E metabolites and to utilize these assays in patients with sepsis (n=5) and control (n=5), to obtain evidence of oxidative stress from 8isoPGp2α concentrations and to investigate whether α-Tocopheronolactone could be used as an invivo biomarker of oxidative stress. A marked increase with a mean ± ISD of 917.1 ± 238.6 and 2521 ± 442.1 pg/mg and 274 ± 148.1 and 29.29 ± 8.323 pmol/mmol was observed for the sepsis patients and controls subjects' urinary concentrations of 8isoPGF2α and α-Tocopheronolactone respectively. No correlation was observed between the concentrations of the metabolites (P > 0.05), but a positive r value indicated the probability of a correlation with an increase in sample size. A high concentration of α-CEHC in the patients' urine (1940 ± 798.7 pmol/mmol) indicated a status of vitamin E status the reason for the increase is unknown and could be attributed to the diet (information unavailable) and also the sepsis state itself, but the formation of artefactual oxidation was ruled out; due to a poor correlation between α-CEHC and α-Tocopheronolactone. Thus the study validated the use of 8isoPGF2α as an independent biomarker of oxidative stress and highlighted the possible role of α-Tocopheronolactone as a biomarker of oxidative stress. The study also suggests further investigation into the role of α-CEHC in oxidative stress and sepsis state