Glutathione and Riboflavin Status in Supplemented Patients Undergoing Home Nocturnal Hemodialysis versus Standard Hemodialysis
published online 13 November 2009. Corrected Proof
Background
Patients on conventional hemodialysis (HD) have elevated markers of oxidative stress and chronic inflammation, which may contribute to a high prevalence of cardiovascular disease. Glutathione (GSH), an important intracellular antioxidant, requires cysteine as a rate-limiting amino acid for its synthesis and riboflavin for its regeneration.
Objectives
We aimed to examine whether erythrocyte GSH (eGSH) concentrations and riboflavin status are influenced by the increased dialysis dose provided to vitamin-supplemented patients receiving home nocturnal hemodialysis (HNHD) (6–8 hours/session, 5–7 nights/week) compared with patients on standard hemodialysis (SHD) (4 hours/session, 3 days/week).
Method
This was a cross-sectional comparative study involving 30 patients undergoing SHD or HNHD regimens and a group of 15 healthy control subjects (HC). We measured eGSH concentration by liquid chromatography–tandem mass spectrometry, riboflavin status by eGSH reductase activity coefficient (EGRAC) as well as plasma total cysteine (Cys) and total homocysteine (Hcy), vitamin C by high-performance liquid chromatography, and C-reactive protein (CRP) by standard method. Estimated dietary protein and energy intakes were determined by 3-day food records, and nutritional status was assessed by subjective global assessment (SGA).
Results
There were no significant differences among groups in eGSH concentration, EGRAC, dietary protein intake, and SGA score. SHD patients had significantly higher plasma Cys (P < .001) and Hcy compared with HNHD and HC groups (P = .048). Vitamin C was significantly lower (P = .01) and CRP significantly higher (P = .048) in both HD groups compared with HC.
Conclusion
eGSH concentration appears to be unaffected by dialysis dose in well-nourished HD patients.
∗The Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital Toronto, Ontario, Canada
†Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
‡The Research Institute, The Hospital for Sick Children Toronto, Ontario, Canada
§Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
∗∗Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
††Department of Paediatrics, University of Toronto, Toronto, Ontario, Canada
‡‡Department of Nephrology, University of Toronto, Toronto, Ontario, Canada
Address reprint requests to Dr. Pauline B. Darling, St. Michael's Hospital, Room 56D, 6th Floor Cardinal Carter Wing, Toronto, Ontario M5B 1W8, Canada.
Funding for this study was provided by a research grant from the Kidney Foundation of Canada.
This study was presented in part as a poster at the Experimental Biology Meeting, New Orleans, Louisiana, April 2009.
ABSTRACT