Simvastatin Enhances Learning and Memory Independent of Amyloid Load in Mice

Ann Neurol. 2006 Dec;60(6):729-39. doi: 10.1002/ana.21053.

Abstract

Objective: Normal aging is often associated with a decline in learning and memory functions. This decline is manifested to a much greater extent in Alzheimer's disease. Recent studies have indicated statins, a class of cholesterol-lowering drugs, as a potential therapy for Alzheimer's disease. Our objective was to determine whether administering a statin drug (simvastatin) would protect against the development of behavioral deficits in an established mouse model of Alzheimer's disease.

Methods: Tg2576 mice and their nontransgenic littermates were treated with simvastatin and assessed by behavioral tests and biochemical analyses.

Results: Simvastatin treatment not only reversed learning and memory deficits in the Tg2576 mice, but also enhanced learning and memory in the nontransgenic mice. Moreover, levels of amyloid beta protein in the brains of treated mice did not differ from those of untreated mice. Simvastatin treatment was associated with increased expression levels of protein kinase B (Akt) and endothelial nitric oxide synthase in the mouse brain.

Interpretation: Our findings demonstrate that the effects of simvastatin on learning and memory are independent of amyloid beta protein levels. The mechanisms by which simvastatin exerts its beneficial effects may be related to modulation of signaling pathways in memory formation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alzheimer Disease / drug therapy*
  • Alzheimer Disease / physiopathology
  • Alzheimer Disease / psychology
  • Animals
  • Anticholesteremic Agents / pharmacology
  • Anticholesteremic Agents / therapeutic use
  • Brain / drug effects*
  • Brain / pathology
  • Brain / physiopathology
  • Cholesterol / metabolism
  • Cytoprotection / drug effects
  • Cytoprotection / physiology
  • Disease Models, Animal
  • Female
  • Learning / drug effects
  • Learning / physiology
  • Learning Disabilities / drug therapy*
  • Learning Disabilities / pathology
  • Learning Disabilities / physiopathology
  • Memory / drug effects
  • Memory / physiology
  • Memory Disorders / drug therapy*
  • Memory Disorders / pathology
  • Memory Disorders / physiopathology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Neuroprotective Agents / pharmacology
  • Neuroprotective Agents / therapeutic use
  • Nitric Oxide Synthase Type III / drug effects
  • Nitric Oxide Synthase Type III / metabolism
  • Plaque, Amyloid / drug effects*
  • Plaque, Amyloid / metabolism
  • Plaque, Amyloid / pathology
  • Proto-Oncogene Proteins c-akt / drug effects
  • Proto-Oncogene Proteins c-akt / metabolism
  • Signal Transduction / drug effects
  • Signal Transduction / physiology
  • Simvastatin / pharmacology*
  • Simvastatin / therapeutic use
  • Treatment Outcome

Substances

  • Anticholesteremic Agents
  • Neuroprotective Agents
  • Cholesterol
  • Simvastatin
  • Nitric Oxide Synthase Type III
  • Proto-Oncogene Proteins c-akt