Enhanced oxidative stress with a gradient between plasma and muscle interstitial fluid in patients with end stage renal failure on hemodialysis

Abstract

The concentration of 8-iso-prostaglandin-F2 alpha (8-iso-PGF2 alpha in biological fluids has been considered as the most reliable biochemical index of the lipid peroxidation and oxidative stress in patients with several pathological conditions including end stage renal failure. However, there is no reference regarding the influence of Hemodialysis (HD) on the values of 8-iso-PGF2 alpha in the muscle Interstitial Fluid (IF) of patients with end stage renal failure. The aim of our study was to determine 8-iso-PGF2 alpha concentration in the IF during hemodialysis and the gradient between plasma and IF in patients with end stage renal failure. In this study, two microdialysis probes were inserted into the vastus lateralis muscle of the right leg of six male patients with end stage renal failure who were on hemodialysis, and in six healthy males (controls). The samples of IF (12 dialysate fluids) were collected after an equilibration of 30 min: a) during the 1st hour preceding hemodialysis (group CRF0), b) during the 1st, 2nd, 3rd and 4th hour while on hemodialysis (groups CRF1, CRF2, CRF3 and CRF4) and c) during the 1st hour following hemodialysis (group CRF5). At the end of the above periods and simultaneously, blood samples were drawn from the arteriovenous fistula. In the controls, the IF samples (twelve dialysate fluids) were collected during a period of one hour and the blood samples at the end of this period. The levels of 8-iso-PGF2 alpha were measured with an enzyme-immunoassay method. Statistical evaluation was carried out with the statistical program NCSS 2000 and the ANOVA test. Plasma and IF levels of 8-iso-PGF2 alpha in the patients were significantly higher than in controls at base line. During hemodialysis, the 8-iso-PGF2 alpha rose progressively both in plasma and IF but remained higher in plasma than in IF. Lipid peroxidation is higher in patients on hemodialysis than in controls but it is lower in the IF compared to plasma. The mechanism for this gradient is speculative.