A novel cell-permeable antioxidant peptide decreases renal tubular apoptosis and damage in unilateral ureteral obstruction

Am J Physiol Renal Physiol. 2008 Nov;295(5):F1545-53. doi: 10.1152/ajprenal.00395.2007. Epub 2008 Sep 10.

Abstract

Unilateral ureteral obstruction (UUO) is characterized by decreases in renal function, increased interstitial fibrosis, tubular apoptosis, and cellular infiltration. It has been suggested that inhibition of tubular apoptosis may protect against renal damage in obstruction. We have recently developed a series of peptides which are concentrated in the inner mitochondrial membrane and prevent cell death. These peptides are also active in vivo, in myocardial infraction, ischemic brain injury, and amyotrophic lateral sclerosis models. We therefore used SS-31, a prototype of these peptides, and assessed its effects on renal damage and oxidative stress in a 14-day obstruction model. SS-31 (1 or 3 mg/kg) or saline was given 1 day before and throughout the 14 days of obstruction. Kidneys were harvested and assessed for apoptosis (terminal transferase-dUTP-nick-end labeling, caspase 3 expression), fibrosis (trichrome staining), macrophage infiltration, fibroblast expression (immunoperoxidase), and oxidative damage (8-OH deoxyguanosine and heme oxygenase-1 expression), cytokines, and signaling pathways (transforming growth factor-beta, CCR-1, p38-MAPK, NF-kappaB). SS-31 significantly attenuated the effects of obstruction on all aspects of renal damage which were examined, with both the 1 and 3 mg/kg doses showing efficacy. We noted increased oxidative stress in obstruction, which was also attenuated by SS-31 treatment. Signaling via NF-kappaB and p38 MAPK pathways were both affected by SS-31 treatment. This study provides a proof of concept that peptides which protect mitochondria in vitro can provide protection from renal damage in a UUO model. The mechanism by which protection is afforded requires further studies both in vitro and in vivo.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • 8-Hydroxy-2'-Deoxyguanosine
  • Animals
  • Antioxidants / pharmacology
  • Antioxidants / therapeutic use
  • Apoptosis / drug effects*
  • Cell Proliferation / drug effects
  • Cytokines / genetics
  • Cytokines / metabolism
  • Deoxyguanosine / analogs & derivatives
  • Deoxyguanosine / metabolism
  • Disease Models, Animal
  • Enzyme-Linked Immunosorbent Assay
  • Fibroblasts / drug effects
  • Fibroblasts / metabolism
  • Fibroblasts / pathology
  • Gene Expression / drug effects
  • Heme Oxygenase-1 / metabolism
  • Intermediate Filament Proteins / metabolism
  • Kidney / drug effects*
  • Kidney / metabolism
  • Kidney / pathology
  • Macrophages / drug effects
  • Macrophages / metabolism
  • Macrophages / pathology
  • Oligopeptides / pharmacology
  • Oligopeptides / therapeutic use*
  • Oxidative Stress / drug effects
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, CCR1 / genetics
  • Receptors, CCR1 / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transcription Factor RelA / genetics
  • Transcription Factor RelA / metabolism
  • Transforming Growth Factor beta / genetics
  • Transforming Growth Factor beta / metabolism
  • Ureteral Obstruction / drug therapy*
  • Ureteral Obstruction / metabolism
  • Ureteral Obstruction / pathology
  • p38 Mitogen-Activated Protein Kinases / genetics
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • Antioxidants
  • Ccr1 protein, rat
  • Cytokines
  • Intermediate Filament Proteins
  • Oligopeptides
  • Receptors, CCR1
  • Transcription Factor RelA
  • Transforming Growth Factor beta
  • arginyl-2,'6'-dimethyltyrosyl-lysyl-phenylalaninamide
  • 8-Hydroxy-2'-Deoxyguanosine
  • Heme Oxygenase-1
  • p38 Mitogen-Activated Protein Kinases
  • Deoxyguanosine