title: Furosemide prevents apoptosis and associated gene expression in a rat model of surgical ischemic acute renal failure.
abstract: Recently, we demonstrated that furosemide improves renal hemodynamics and attenuates ischemia/reperfusion (I/R)-associated changes in angiogenesis-related gene expression. However, the effect of furosemide on I/R-induced apoptosis is not known. We utilized a rat model of acute ischemic nephropathy to test the hypothesis that furosemide attenuates I/R-induced apoptosis. Male Sprague-Dawley rats anesthetized with urethane (50 mg/kg) were randomly allocated into four groups (n = 6 each): sham operated saline infusion, sham operated with furosemide (30 microg/kg/hr) infusion, unilateral renal ischemia (1 hr) followed by six hours of reperfusion, and I/R with furosemide infusion. Apoptosis was measured in kidney samples and compared between groups using ANOVA with Bonferroni correction. Apoptosis-related gene expression was assessed using microarray analysis and validated with RT-PCR. Phosphorylation of Akt was analyzed using ELISA, and data were compared between groups using the Mann Whitney U test. Compared to the control group, I/R significantly (p < 0.001) induced apoptosis in both the cortex and medulla. Similarly, microarray analysis revealed that I/R induced (< or = two-fold increase compared to control group) 73 apoptosis-related genes. Phosphorylation of Akt was significantly (p < 0.05) downregulated after I/R. Treatment with furosemide significantly (p < 0.001) reduced I/R-induced apoptosis in both the cortex and medulla and attenuated the expression of 72 I/R-induced apoptosis-related genes. Compared to the I/R group, furosemide significantly (p < 0.01) upregulated the phosphorylation of Akt. These data suggest that a low dose furosemide infusion may attenuate I/R-induced apoptosis and associated gene transcription, and imply a possible novel molecular basis for the mechanism of action of furosemide in acute renal failure.
authors.affiliation: Department of Radiation Oncology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma 73104, USA. naravind@ouhsc.edu
authors.forename: Natarajan
authors.initials: N
authors.lastname: Aravindan
authors.forename: Sheeja
authors.initials: S
authors.lastname: Aravindan
authors.forename: Bernhard J
authors.initials: BJ
authors.lastname: Riedel
authors.forename: Han-Rong
authors.initials: HR
authors.lastname: Weng
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Shaw
mesh_terms: D058186:Acute Kidney Injury / Q000235:genetics / Q000503:physiopathology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D053938:DNA Fragmentation; D004195:Disease Models, Animal; D004232:Diuretics / Q000494:pharmacology*; D005665:Furosemide / Q000494:pharmacology*; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000503:physiopathology
chemical_list: D004232:Diuretics; D005665:Furosemide; D051057:Proto-Oncogene Proteins c-akt