Molecular and Cellular Biochemistry

, Volume 290, Issue 1–2, pp 23–32

Forskolin, an inducer of cAMP, up-regulates acetylcholinesterase expression and protects against organophosphate exposure in neuro 2A cells

  • Bryan F. Curtin
  • Nabaneeta Pal
  • Richard K. Gordon
  • Madhusoodana P. Nambiar


Bioscavenger prophylactic therapy using purified human acetylcholinesterase (AChE) or butylcholinesterase (BChE) is a promising treatment for future protection against chemical warfare nerve agent exposure. Potential immune response due to the complex structure of cholinesterases, mutations, post-translational modifications, and genetic variation is a limiting factor against purified enzyme therapy. We investigated an alternative bioscavenger approach using Forskolin, an inducer of intracellular cyclic AMP (cAMP), which activates AChE promoter and up-regulates its expression. A mouse neuronal cell line, Neuro 2A, was treated with various doses of Forskolin and analysis of the expressed enzyme indicates that the AChE activity was significantly increased in cells exposed to repeated administration of the drug every other day for 7–10 days. Cholinesterase enzyme assays showed that the enzyme activity was increased approximately 2-fold for the extracellular enzyme and 3-fold for the intracellular enzyme. The optimal dose found for extracellular enzyme production was 12–24 μM Forskolin, while the optimal dose for intracellular was 12 μM. In parallel with the rise in the AChE level, the morphology of Forskolin-treated cells showed neurite growth with increasing doses. Forskolin treatment protects Neuro 2A cells from Diisopropylflurophophate (DFP), a surrogate of the organophosphate chemical warfare agents soman and sarin, induced toxicity in Neuro 2A cells. These results indicate that transcriptional inducers, such as Forskolin, can sufficiently up-regulate cellular AChE production and protect cells against organophosphate toxicity.


acetylcholinesterase organophosphates transcriptional regulators neuronal cell lines gene expression neuroprotection 


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • Bryan F. Curtin
    • 1
  • Nabaneeta Pal
    • 1
  • Richard K. Gordon
    • 1
  • Madhusoodana P. Nambiar
    • 1
    • 2
  1. 1.Department of Biochemical Pharmacology, Division of BiochemistryWalter Reed Army Institute of ResearchSilver SpringUSA
  2. 2.Department of MedicineUniformed Services University of the Health SciencesBethesdaUSA

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