Reactive oxygen species mediate compensatory glomerular hypertrophy in rat uninephrectomized kidney.
Hyperfiltration in glomeruli is the most common pathway to progressive renal dysfunction. Moreover, reduction of renal mass by unilateral nephrectomy results in an immediate increase in glomerular flow to the remnant kidney, followed by compensatory glomerular hypertrophy. Reactive oxygen species (ROS) are involved in renal hypertrophic responses; however, the role of ROS in compensatory glomerular hypertrophy remains unclear. Therefore, this role was investigated in the present study. Wistar rats were randomly placed into two groups: uninephrectomized rats (Nx) and uninephrectomized rats treated with tempol (Nx + TP). The glomerular volume increased in the Nx 1 week after surgery, but was significantly suppressed in the Nx + TP. Levels of phospho-Akt and phospho-ribosomal protein S6, which are critical for cell growth and hypertrophy, were markedly increased in the glomeruli of the Nx, while tempol treatment almost abolished the activation of these proteins. These results suggest that ROS have important roles in compensatory hypertrophy in glomeruli.
Ozeki
Masahito
M
Division of Nephrology, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192, Japan.
Nagasu
Hajime
H
Satoh
Minoru
M
Namikoshi
Tamehachi
T
Haruna
Yoshisuke
Y
Tomita
Naruya
N
Sasaki
Tamaki
T
Kashihara
Naoki
N
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D003497:Cyclic N-Oxides / Q000494:pharmacology; D005919:Glomerular Filtration Rate / Q000187:drug effects / Q000502:physiology; D006984:Hypertrophy / Q000378:metabolism / Q000473:pathology; D007668:Kidney / Q000601:surgery*; D007678:Kidney Glomerulus / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D009392:Nephrectomy / Q000379:methods*; D009569:Nitric Oxide / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism*; D038601:Ribosomal Protein S6 / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D013113:Spin Labels; D058570:TOR Serine-Threonine Kinases
D000975:Antioxidants; D003497:Cyclic N-Oxides; D017382:Reactive Oxygen Species; D038601:Ribosomal Protein S6; D013113:Spin Labels; D009569:Nitric Oxide; D011494:Protein Kinases; C546845:mTOR protein, rat; D051057:Proto-Oncogene Proteins c-akt; D058570:TOR Serine-Threonine Kinases; C001803:tempol