Pretreatment with glutamine attenuates anoxia/reoxygenation injury of human proximal renal tubular epithelial cells via induction of heme oxygenase-1.
OBJECTIVE
Glutamine showed potential cytoprotective activity probably due to induction of heme oxygenase-1 (HO-1). We thus investigated the effect of glutamine in vitro on anoxia/reoxygenation (A/R) injury of renal tubular epithelial cells.


METHODS
Human proximal renal tubular epithelial cells (HK-2) were subjected to A/R with or without glutamine, after which viability and apoptosis of the cells were determined by MTT assay and annexin V flow cytometry, respectively. Meanwhile, expression of HO-1, caspase-3, Bcl-2 and inducible nitric oxide synthetase (iNOS) was measured by reverse transcriptase polymerase chain reaction and Western blot.


RESULTS
A/R significantly induced apoptosis of HK-2 cells, which was inhibited by glutamine, during which HO-1 was upregulated significantly, but nullified by p38MAPK inhibitor. Caspase-3 and iNOS increased after A/R; however, glutamine inhibited this potential. Opposite results were observed for Bcl-2.


CONCLUSIONS
Glutamine prevents A/R injury of HK-2 cells through induction of HO-1 via a p38MAPK-dependent pathway, which plays a key role in the cytoprotective effect of glutamine.
Shi
Qiang
Q
Department of Radiology, The First Affiliated Hospital, China Medical University, Shenyang, China.
Feng
Ya-Ni
YN
Fang
Jun
J
Xu
Ke
K
D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D015687:Cell Hypoxia; D002478:Cells, Cultured; D019610:Cytoprotection; D004847:Epithelial Cells / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D005973:Glutamine / Q000494:pharmacology*; D051547:Heme Oxygenase-1 / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D006801:Humans; D007687:Kidney Tubules, Proximal / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D009569:Nitric Oxide / Q000235:genetics; D019001:Nitric Oxide Synthase / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010100:Oxygen / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D015427:Reperfusion Injury / Q000201:enzymology / Q000473:pathology / Q000517:prevention & control
D000975:Antioxidants; D019253:Proto-Oncogene Proteins c-bcl-2; D005973:Glutamine; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D051547:Heme Oxygenase-1; D053148:Caspase 3; D010100:Oxygen