TY - JOUR
T1 - Glyoxylate reductase activity in blood mononuclear cells and the diagnosis of primary hyperoxaluria type 2
AU - Knight, John
AU - Holmes, Ross P.
AU - Milliner, Dawn S.
AU - Monico, Carla G.
AU - Cramer, Scott D.
N1 - Funding Information:
Acknowledgements. The authors gratefully acknowledge the invaluable contribution of Ying Yang for assisting with these experiments. This research was supported by NIH grants DK54468 and DK73354, and the authors thank Oxalosis and Hyperoxaluria Foundation, which supported the Mayo Clinic Hyperoxaluria Center.
PY - 2006/8
Y1 - 2006/8
N2 - Background. Primary hyperoxaluria type 2 (PH2) is a rare monogenic disorder characterized by an elevated urinary excretion of oxalate. Increased oxalate excretion in PH2 patients can cause nephrolithiasis and nephrocalcinosis, and can, in some cases, result in renal failure and systemic oxalate deposition. The disease is due to a deficiency of glyoxylate reductase/hydroxypyruvate reductase (GRHPR) activity. A definitive diagnosis of PH2 is currently made by the analysis of GR activity in a liver biopsy. GRHPR is expressed in virtually every tissue in the body, suggesting that utilization of more readily available cells could be used to determine GRHPR deficiency. In this study, we have evaluated the potential of determining GR and d -glycerate dehydrogenase (DGDH) activity in blood mononuclear cells (BMC) as a diagnostic indicator of PH2. Methods. Blood samples were obtained from 10 male and 10 female normal subjects, median age 31, range 21-63, at the Wake Forest University Medical Center and from primary hyperoxaluria patients at the Mayo Clinic. The BMC were isolated and GR and DGDH activities measured in cell lysates. Results. An assay of 20 normal individuals indicated that BMC contained a DGDH and GR activity of 0.97±0.20 (range 0.62-1.45), and 10.6±3.3 (range 8.3-16.6) nmol/min/mg protein, respectively. The intra-assay coefficient of variation for DGDH and GR activity was 8.2 and 11.5%, respectively. The BMC lysates from al adult subjects and patients with PH1 showed similar GR and DGDH activities. This was confirmed by the presence of immunoreactive GRHPR protein by western blot analysis. In contrast, PH2 BMC lysates did not exhibit DGDH or GR activity, and showed no immunoreactive GRHPR by western blot analysis. Conclusion. These results suggest that the assay of DGDH or GR activity in BMC could be used as a minimally invasive diagnostic test for PH2.
AB - Background. Primary hyperoxaluria type 2 (PH2) is a rare monogenic disorder characterized by an elevated urinary excretion of oxalate. Increased oxalate excretion in PH2 patients can cause nephrolithiasis and nephrocalcinosis, and can, in some cases, result in renal failure and systemic oxalate deposition. The disease is due to a deficiency of glyoxylate reductase/hydroxypyruvate reductase (GRHPR) activity. A definitive diagnosis of PH2 is currently made by the analysis of GR activity in a liver biopsy. GRHPR is expressed in virtually every tissue in the body, suggesting that utilization of more readily available cells could be used to determine GRHPR deficiency. In this study, we have evaluated the potential of determining GR and d -glycerate dehydrogenase (DGDH) activity in blood mononuclear cells (BMC) as a diagnostic indicator of PH2. Methods. Blood samples were obtained from 10 male and 10 female normal subjects, median age 31, range 21-63, at the Wake Forest University Medical Center and from primary hyperoxaluria patients at the Mayo Clinic. The BMC were isolated and GR and DGDH activities measured in cell lysates. Results. An assay of 20 normal individuals indicated that BMC contained a DGDH and GR activity of 0.97±0.20 (range 0.62-1.45), and 10.6±3.3 (range 8.3-16.6) nmol/min/mg protein, respectively. The intra-assay coefficient of variation for DGDH and GR activity was 8.2 and 11.5%, respectively. The BMC lysates from al adult subjects and patients with PH1 showed similar GR and DGDH activities. This was confirmed by the presence of immunoreactive GRHPR protein by western blot analysis. In contrast, PH2 BMC lysates did not exhibit DGDH or GR activity, and showed no immunoreactive GRHPR by western blot analysis. Conclusion. These results suggest that the assay of DGDH or GR activity in BMC could be used as a minimally invasive diagnostic test for PH2.
KW - Blood mononuclear cells
KW - D-glycerate dehydrogenase
KW - Glyoxylate reductase
KW - Primary hyperoxaluria type 2
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U2 - 10.1093/ndt/gfl142
DO - 10.1093/ndt/gfl142
M3 - Article
C2 - 16597637
AN - SCOPUS:33748059855
SN - 0931-0509
VL - 21
SP - 2292
EP - 2295
JO - Nephrology Dialysis Transplantation
JF - Nephrology Dialysis Transplantation
IS - 8
ER -