Pharmacological activation of protein kinase A improves memory loss and neuropathological changes in a mouse model of dementia of Alzheimer's type

Behav Pharmacol. 2017 Apr;28(2 and 3-Spec Issue):187-198. doi: 10.1097/FBP.0000000000000294.

Abstract

The study investigates the therapeutic potential of the protein kinase A (PKA) activator forskolin in cognitive deficits of mice. Streptozotocin (STZ) [3 mg/kg, intracerebroventricularly (i.c.v.)] was used to induce memory deficits in mice, whereas aged mice served as natural model of dementia. Forskolin (2.5, 5, and 10 mg/kg/day, oral) treatment was administered to i.c.v. STZ-treated and aged mice for 14 days. The Morris Water Maze test was used to evaluate learning and memory. Estimation of brain acetylcholinesterase (AChE) activity, brain glutathione, thiobarbituric acid-reactive species, brain myeloperoxidase levels, and histopathological studies were also performed. Both STZ i.c.v. and aging resulted in a marked decline in Morris Water Maze performance, reflecting impairment of learning and memory. STZ i.c.v.-treated mice and aged mice showed a marked accentuation of AChE activity, thiobarbituric acid-reactive species and myeloperoxidase levels along with a decrease in the glutathione level. Further, the stained micrographs of STZ-treated mice and aged mice indicated pathological changes, severe neutrophilic infiltration, and amyloid deposition. Forskolin treatment significantly attenuated STZ-induced and age-related memory deficits, and biochemical and histopathological alterations. The findings indicate that the PKA activator forskolin probably alleviated memory deficits by virtue of its anticholinesterase, antiamyloid, antioxidative, and anti-inflammatory effects. It is concluded that PKA could be explored as a potential therapeutic target in dementia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcholinesterase / metabolism*
  • Alzheimer Disease / drug therapy*
  • Alzheimer Disease / physiopathology
  • Animals
  • Brain / drug effects
  • Brain / physiopathology
  • Cholinesterase Inhibitors / pharmacology
  • Colforsin / administration & dosage
  • Colforsin / pharmacology*
  • Cyclic AMP-Dependent Protein Kinases / drug effects*
  • Cyclic AMP-Dependent Protein Kinases / metabolism
  • Dementia / drug therapy
  • Dementia / physiopathology
  • Disease Models, Animal
  • Female
  • Glutathione / metabolism
  • Male
  • Maze Learning / drug effects
  • Memory Disorders / drug therapy
  • Mice
  • Streptozocin

Substances

  • Cholinesterase Inhibitors
  • Colforsin
  • Streptozocin
  • Cyclic AMP-Dependent Protein Kinases
  • Acetylcholinesterase
  • Glutathione