Oxidative Stress in Children on Peritoneal Dialysis

Abstract

Objectives Enhanced oxidative stress has been observed in dialysis and predialysis adult patients with chronic kidney disease (CKD), which resulted in increased mortality and morbidity within this population. Not much attention in the literature has been paid to nonenzymatic antioxidant defense in children with CKD on peritoneal dialysis (PD). The aim of the present study was to describe the plasma, erythrocyte, and dialysate concentrations of oxidized (GSSG) and reduced glutathione (GSH) and vitamins A, E, and C in a pediatric PD population. Patients 10 children on PD and 27 age-matched healthy subjects were enrolled in the study. Results Erythrocyte and plasma GSH concentrations were lower in PD patients, erythrocyte concentration of GSSG remained unchanged, and plasma GSSG was significantly higher in children on PD. Children on PD exhibited decreased plasma concentrations of antioxidant vitamins compared to healthy subjects. Moreover, we documented loss of vitamins A, E, and C into ultrafiltrate. Conclusion Such low plasma levels of vitamins A, E, and C and simultaneously decreased activity of erythrocyte GSH may be responsible for the increased oxidative stress occurring in children with CKD on PD.

Oxidative Stress in Patients Undergoing Peritoneal Dialysis: A Current Review of the Literature

“…Moreover, PD patients presented a pronounced deficiency of antioxidants, as expressed by lower serum levels of ascorbic acid, vitamin E, and glutathione when compared to the control group [ 25 ]. Zwolinska et al found that children on PD had reduced activity of GSH in RBCs and plasma and significantly decreased levels of antioxidant vitamins A, C, and E—due to loss of these vitamins into the ultrafiltrate—compared to age-matched healthy controls [ 26 ].…”

Low levels of vitamin C in dialysis patients is associated with decreased prealbumin and increased C-reactive protein

“…Furthermore, since various pro-inflammatory cytokines were promoted due to metabolic acidosis [ 12 ], volume overload [ 13 ], and non-sterile dialysate [ 14 ], patients were usually on mirco-inflammation status [ 15 , 16 ]. On the other side, antioxidant levels, such as plasma vitamin C level and reduced glutathione level, were usually decreased [ 3 , 5 , 17 , 18 ]. It was documented that inflammation was associated with increased risk of cardiovascular morbidity and mortality in patients on dialysis [ 19 , 20 ].…”

Endogenously elevated bilirubin modulates kidney function and protects from circulating oxidative stress in a rat model of adenine-induced kidney failure

“…These data are in agreement with previous studies including individuals with benign hyperbilirubinemia who also possess significantly elevated GSH and SH concentrations compared to controls, the concentration of which was positively correlated with unconjugated bilirubin (UCB) concentrations 37 43 . The glutathione antioxidant system is regarded as an important marker of oxidative stress in chronic kidney disease 44 45 . Previous studies have shown that the uraemic state is associated with low concentrations of GSH and reduced thiols (SH), which continue to decrease with the progression of kidney failure in dialysis patients 45 .…”

“…The glutathione antioxidant system is regarded as an important marker of oxidative stress in chronic kidney disease 44 45 . Previous studies have shown that the uraemic state is associated with low concentrations of GSH and reduced thiols (SH), which continue to decrease with the progression of kidney failure in dialysis patients 45 . Our findings, therefore, may indicate that bilirubin plays an important role in maintaining circulating thiol status providing an important pool of antioxidant capacity, which can protect proteins and lipids from oxidation by oxidants produced during inflammation, namely hypochlorous acid produced from myeloperoxidase (MPO) 46 .…”