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. 2010 Feb;24(2):609-16.
doi: 10.1096/fj.09-135731. Epub 2009 Oct 5.

Glucose-6-phosphate dehydrogenase-deficient mice have increased renal oxidative stress and increased albuminuria

Yizhen Xu  1 , Zhaoyun Zhang, Ji Hu, Isaac E Stillman, Jane A Leopold, Diane E Handy, Joseph Loscalzo, Robert C Stanton
Affiliations

Glucose-6-phosphate dehydrogenase-deficient mice have increased renal oxidative stress and increased albuminuria

Yizhen Xu et al. FASEB J. 2010 Feb.

Abstract

Glucose-6-phosphate dehydrogenase (G6PD) is the rate-limiting enzyme of the pentose phosphate pathway and the principal source of NADPH, a major cellular reductant, and is central to cell survival. Our previous work showed that diabetes and increased aldosterone are acquired forms of G6PD deficiency, leading to decreased G6PD activity and NADPH levels and damage to kidney tissue and endothelial cells. In this study, G6PD-deficient mice were studied to test the hypothesis that decreased G6PD activity per se can cause changes similar to those seen in the acquired conditions of G6PD deficiency. Results show that as compared with control mice, G6PD-deficient mice had increased oxidative stress, as manifested by decreased NADPH levels and decreased GSH levels, and increased markers of lipid peroxidation. G6PD-deficient mice had increased protein kinase C activity, increased nuclear factor-kappaB activity, and increased urinary albumin levels, all of which is similar to changes seen in diabetic mice. Changes persisted as the mice aged, as old G6PD-deficient mice (17-20 mo) had higher urine albumin levels and also had evidence for increased apoptosis in the renal cortex. These results show that decreased G6PD activity per se is sufficient to cause changes similar to those seen in diabetic mice.

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Figures

Figure 1.
Figure 1.
NADPH levels in kidney cortex from WT, heterozygous (HET), and homozygous (HOM) G6PD-deficient mice. Heterozygotes had ∼50% of WT NADPH level, and homozygotes had ∼32% of the WT level. Values are expressed as means ± se. WT, n = 4; heterogyzous, n = 4; homozygous, n = 3. *P < 0.05 vs. WT control.
Figure 2.
Figure 2.
PKC activity was increased in kidney cortex from heterozygous (HET) and homozygous (HOM) G6PD-deficient mice as compared to WT. Increased PKC activity has been shown in many pathophysiological inflammatory processes. The significant increases in PKC suggest that there is increased inflammation in G6PD-deficient mice. Values are expressed as means ± se. WT, n = 4; heterogyzous, n = 4; homozygous, n = 3. *P < 0.05 vs. WT control.
Figure 3.
Figure 3.
ΙκΒ protein expression in kidney cortex was decreased in heterozygous (HET) and homozygous (HOM) G6PD-deficient mice as compared to WT control. Decreased ΙκΒ protein reflects increased NF-κΒ protein expression, which is a mediator of inflammatory processes. Thus, the significant decreases of ΙκΒ protein in G6PD-deficient mice suggest that there is increased inflammation in these mice as compared to WT mice. A) Representative Western blot for G6PD and β-actin expression from 3 experimental groups. See Materials and Methods for experimental protocols. B) Summary of ΙκΒ protein expression as determined by densitometric analysis and normalized to β-actin expression. Values are expressed as means ± se for 3 experiments. WT, n = 4; heterogyzous, n = 4; homozygous, n = 3. *P < 0.05 vs. control.
Figure 4.
Figure 4.
Urinary microalbumin level is increased in heterozygous (Het) and homozygous (Homo) G6PD-deficient mice as compared to WT control in 22-wk-old mice and 17- to 20-mo-old mice. An early marker of kidney damage or kidney inflammation is increased urine albumin levels. Data show that G6PD-deficient mice have highly significant increases in urine albumin levels by 22 wk that is seen even in the old mice. Alb/cr is the measure of albumin in the urine collection normalized to the urine creatinine value. Values are expressed as means ± se. Mice/group, 22 wk: WT, n = 4; heterogyzous, n = 4; homozygous, n = 3. Mice/group, 17–20 mo: WT, n = 4; heterozygous, n = 3; homozygous, n = 4; hemizgous (Hemi), n = 3. *P < 0.05 vs. WT control.
Figure 5.
Figure 5.
ΙκΒ protein expression in kidney cortex was decreased in hemizygous (Hemi) and homozygous (Homo) G6PD-deficient mice as compared to WT control in old mice. Similar to the young mice, older G6PD-deficient mice have decreased ΙκΒ protein, suggesting continued activation of NF-κΒ protein as compared to the WT mice, at least in the mice expressing the lowest G6PD activity (hemizygotes). Representative immunoblots are shown above the aggregate data. WT, n = 4; heterozygous, n = 3; homozygous, n = 4; hemizgous, n = 3. *P < 0.05 vs. WT control.
Figure 6.
Figure 6.
Bax protein expression in kidney cortex from old mice was increased in hemizygous (Hemi) males, and there was a trend to increase in homozygous (Homo) female G6PD deficient mice as compared to WT control. Increased expression of Bax protein reflects increased apoptosis. The G6PD deficient mice have an increased expression of BAX protein, suggesting a higher percentage of cells undergoing apoptosis as compared to the WT mice. Representative immunoblots are shown above the aggregate data. WT, n = 4; heterozygous, n = 3; homozygous, n = 4; hemizgous, n = 3. *P < 0.05 vs. WT control.
Figure 7.
Figure 7.
Histopathology of a hemizygous mouse with the greatest degree of proteinuria (urinary albumin/creatinine 1.6). As noted, no significant pathological lesions were noted in any of the groups. A) Light microscopy image showing unremarkable glomeruli and preserved tubulointerstitium (hematoxylin and eosin; original view ×40). B) Electronmicroscopy of a glomerulus shows unremarkable basement membranes, as well as intact endothelial fenestrations and podocyte foot processes (original view ×15,000). C) Electron microscopy image of mitochondria along the basolateral membrane of a proximal tubule. Note intact lamellar and tubular cristae within the rod-shaped mitochondria (original view ×60,000).
See this image and copyright information in PMC

References

    1. Munro A W, Girvan H M, McLean K J. Cytochrome P450-redox partner fusion enzymes. Biochim Biophys Acta. 2007;1770:345–359. - PubMed
    1. Leopold J A, Cap A, Scribner A W, Stanton R C, Loscalzo J. Glucose 6-phosphate dehydrogenase deficiency promotes endothelial oxidant stress and decreases nitiric oxide bioavailability. FASEB J. 2001;15:1771–1773. - PubMed
    1. Leopold J A, Zhang Y Y, Scribner A A, Stanton R C, Loscalzo J. Glucose 6-phosphate dehydrogenase overexpression decreases endothelial cell oxidant stress and increases bioavailable nitric oxide. Arterioscler Thromb Vasc Biol. 2003;23:411–417. - PubMed
    1. Horton J D. Sterol regulatory element-binding proteins: transcriptional activators of lipid synthesis. Biochem Soc Trans. 2002;30:1091–1095. - PubMed
    1. Muller G, Morawietz H. NAD(P)H oxidase and endothelial dysfunction. Horm Metab Res. 2009;41:152–158. - PubMed

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