Renoprotective Effects of Atorvastatin in Diabetic Mice: Downregulation of RhoA and Upregulation of Akt/GSK3

PLoS One. 2016 Sep 20;11(9):e0162731. doi: 10.1371/journal.pone.0162731. eCollection 2016.

Abstract

Potential benefits of statins in the treatment of chronic kidney disease beyond lipid-lowering effects have been described. However, molecular mechanisms involved in renoprotective actions of statins have not been fully elucidated. We questioned whether statins influence development of diabetic nephropathy through reactive oxygen species, RhoA and Akt/GSK3 pathway, known to be important in renal pathology. Diabetic mice (db/db) and their control counterparts (db/+) were treated with atorvastatin (10 mg/Kg/day, p.o., for 2 weeks). Diabetes-associated renal injury was characterized by albuminuria (albumin:creatinine ratio, db/+: 3.2 ± 0.6 vs. db/db: 12.5 ± 3.1*; *P<0.05), increased glomerular/mesangial surface area, and kidney hypertrophy. Renal injury was attenuated in atorvastatin-treated db/db mice. Increased ROS generation in the renal cortex of db/db mice was also inhibited by atorvastatin. ERK1/2 phosphorylation was increased in the renal cortex of db/db mice. Increased renal expression of Nox4 and proliferating cell nuclear antigen, observed in db/db mice, were abrogated by statin treatment. Atorvastatin also upregulated Akt/GSK3β phosphorylation in the renal cortex of db/db mice. Our findings suggest that atorvastatin attenuates diabetes-associated renal injury by reducing ROS generation, RhoA activity and normalizing Akt/GSK3β signaling pathways. The present study provides some new insights into molecular mechanisms whereby statins may protect against renal injury in diabetes.

MeSH terms

  • Animals
  • Anticholesteremic Agents / pharmacology
  • Atorvastatin / pharmacology*
  • Diabetes Mellitus / metabolism
  • Diabetes Mellitus / prevention & control*
  • Down-Regulation / drug effects
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Glycogen Synthase Kinase 3 / metabolism*
  • Immunoblotting
  • Immunohistochemistry
  • Kidney / drug effects
  • Kidney / metabolism
  • Kidney / pathology
  • Male
  • Mice
  • NADPH Oxidase 4
  • NADPH Oxidases / metabolism
  • Phosphorylation / drug effects
  • Protective Agents / pharmacology
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Reactive Oxygen Species / metabolism
  • Signal Transduction / drug effects
  • Up-Regulation / drug effects
  • rho GTP-Binding Proteins / metabolism*
  • rhoA GTP-Binding Protein

Substances

  • Anticholesteremic Agents
  • Protective Agents
  • Reactive Oxygen Species
  • Atorvastatin
  • NADPH Oxidase 4
  • NADPH Oxidases
  • Nox4 protein, mouse
  • Proto-Oncogene Proteins c-akt
  • Extracellular Signal-Regulated MAP Kinases
  • Glycogen Synthase Kinase 3
  • RhoA protein, mouse
  • rho GTP-Binding Proteins
  • rhoA GTP-Binding Protein