Cognitive Impairments Induced by Concussive Mild Traumatic Brain Injury in Mouse Are Ameliorated by Treatment with Phenserine via Multiple Non-Cholinergic and Cholinergic Mechanisms

PLoS One. 2016 Jun 2;11(6):e0156493. doi: 10.1371/journal.pone.0156493. eCollection 2016.

Abstract

Traumatic brain injury (TBI), often caused by a concussive impact to the head, affects an estimated 1.7 million Americans annually. With no approved drugs, its pharmacological treatment represents a significant and currently unmet medical need. In our prior development of the anti-cholinesterase compound phenserine for the treatment of neurodegenerative disorders, we recognized that it also possesses non-cholinergic actions with clinical potential. Here, we demonstrate neuroprotective actions of phenserine in neuronal cultures challenged with oxidative stress and glutamate excitotoxicity, two insults of relevance to TBI. These actions translated into amelioration of spatial and visual memory impairments in a mouse model of closed head mild TBI (mTBI) two days following cessation of clinically translatable dosing with phenserine (2.5 and 5.0 mg/kg BID x 5 days initiated post mTBI) in the absence of anti-cholinesterase activity. mTBI elevated levels of thiobarbituric acid reactive substances (TBARS), a marker of oxidative stress. Phenserine counteracted this by augmenting homeostatic mechanisms to mitigate oxidative stress, including superoxide dismutase [SOD] 1 and 2, and glutathione peroxidase [GPx], the activity and protein levels of which were measured by specific assays. Microarray analysis of hippocampal gene expression established that large numbers of genes were exclusively regulated by each individual treatment with a substantial number of them co-regulated between groups. Molecular pathways associated with lipid peroxidation were found to be regulated by mTBI, and treatment of mTBI animals with phenserine effectively reversed injury-induced regulations in the 'Blalock Alzheimer's Disease Up' pathway. Together these data suggest that multiple phenserine-associated actions underpin this compound's ability to ameliorate cognitive deficits caused by mTBI, and support the further evaluation of the compound as a therapeutic for TBI.

MeSH terms

  • Animals
  • Brain Concussion / complications
  • Brain Concussion / drug therapy*
  • Brain Concussion / pathology
  • Cholinergic Agents / administration & dosage
  • Cholinesterase Inhibitors / administration & dosage
  • Cognitive Dysfunction / drug therapy*
  • Cognitive Dysfunction / etiology
  • Cognitive Dysfunction / pathology
  • Disease Models, Animal
  • Gene Expression Regulation / drug effects
  • Glutamic Acid / metabolism
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Humans
  • Lipid Peroxidation / drug effects
  • Maze Learning / drug effects
  • Mice
  • Neurons / drug effects
  • Neurons / pathology
  • Oxidative Stress / drug effects*
  • Physostigmine / administration & dosage
  • Physostigmine / analogs & derivatives*

Substances

  • Cholinergic Agents
  • Cholinesterase Inhibitors
  • Glutamic Acid
  • Physostigmine
  • phenserine

Grant support

This research was supported in part by (i) the Intramural Research Program of the National Institute on Aging, National Institutes of Health, (ii) the Ari and Regine Aprijaskis Fund, at Tel-Aviv University, and (iii) a grant from the Israel Science Foundation, grant number 108/09. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.