Original ContributionProtection of podocytes from hyperhomocysteinemia-induced injury by deletion of the gp91phox gene
Section snippets
Animal procedures
C57BL/6J wild-type (WT; 6 weeks of age, male) and gp91phox knockout (KO) mice (6 weeks of age, male; The Jackson Laboratory, Bar Harbor, ME, USA) were used. All protocols were approved by the Institutional Animal Care and Use Committee of the Virginia Commonwealth University. Given the difficulty of the development of hyperhomocysteinemia in mice with both kidneys because of treatment that requires a long period of time, all gp91phox KO mice and WT mice were subjected to a uninephrectomy, which
Reduction of hHcys-induced O2â production in gp91phox KO mice
As shown by HPLC analysis, plasma Hcys levels were similar in WT and gp91phox KO mice on the normal diet. FF diet treatment significantly increased plasma Hcys levels in both WT and gp91phox KO mice (Fig. 1A). ESR analysis showed that glomerular O2â production was lower in KO mice than in WT mice on the normal diet. On the FF diet, glomerular O2â production increased by 2.4-fold in WT mice. However, FF diet-induced O2â production was much less in KO mice compared with WT mice (Figs. 1B and 1C).
Alleviation of glomerular injury in gp91phox KO mice on the FF diet
Discussion
The goals of this study were to determine whether podocytes are a direct target of hHcys and to investigate the role of NADPH oxidase-dependent O2â production in hHcys-induced podocyte injury. Using an FF diet-induced hHcys animal model in gp91phox gene-deficient mice and in vitro cultured podocytes, we clearly demonstrated that hHcys directly induces podocyte injury and depletion through gp91phox-containing NADPH oxidase activation and O2â production.
There is considerable evidence supporting
Acknowledgments
This study was supported by Grants DK54927, HL075316, and HL57244 from the National Institutes of Health.
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