TITLE:
Short-term antioxidant diet prevents hyperfiltration in young male rat kidney subjected to ischemia/reperfusion injury
AUTHORS:
Yuriy Slyvka, Felicia V. Nowak, Tracey M. Hayes, Sharon R. Inman
KEYWORDS:
Antioxidants; Ischemia/Reperfusion; Kidney; Nitric Oxide Synthase
JOURNAL NAME:
Open Journal of Molecular and Integrative Physiology,
Vol.3 No.1,
February
22,
2013
ABSTRACT: Objectives: The process of transplantation is associated with exposure to both long and short cold and warm ischemic times that
result in ischemia/reperfusion injury. Oxidative stress contributes to tissue
fibrosis, renal dysfunction, and/or rejection. Treatments that scavenge
oxygen free radicals and have antioxidant properties can ameliorate the damaging
results in renal grafts following ischemia/reperfusion injury. The present
study tests the hypothesis that an antioxidant-fortified diet given to rats
before and after renal ischemia/reperfusion injury will reduce the kidney
damage that results and improve renal function. Endothelial and inducible
nitric oxide synthases may change with tissue injury, including ischemia/ reperfusion.
Materials and Methods: Male Wistar rats were subjected to ischemia/reperfusion
injury at 7 or 19 weeks of age with or without dietary antioxidant
supplementation. One week later, glomerular filtration rate, mean arterial
pressure and urinary nitric oxide were measured, and renal endothelial and
inducible nitric oxide synthases examined. Results: The glomerular filtration
rate was elevated more than two-fold above the normal range at 8 weeks in animals on the regular diet
exposed to ischemia/reperfu- sion, while in the 8 week antioxidant-fortified
diet group the glomerular filtration rate was normal. Also, in 8 week rats,
levels of endothelial nitric oxide synthase protein in cortex were higher on
the regular than on the antioxidant-fortified diet. Conclusion: Early after ischemia/reperfusion injury renal endothelial
nitric oxide synthase levels rise, possibly contributing to vascular dilation
and hyperperfusion, and an antioxidant-fortified diet can ameliorate these
changes in the younger age group.