L-serine treatment may improve neurorestoration of rats after permanent focal cerebral ischemia potentially through improvement of neurorepair

PLoS One. 2014 Mar 26;9(3):e93405. doi: 10.1371/journal.pone.0093405. eCollection 2014.

Abstract

The present study was conducted to clarify whether treatment with L-serine can improve the brain repair and neurorestoration of rats after permanent middle cerebral artery occlusion (pMCAO). After pMCAO, the neurological functions, brain lesion volume, and cortical injury were determined. GDNF, NGF, NCAM L1, tenascin-C, and Nogo-A levels were measured. Proliferation and differentiation of the neural stem cells (NSCs) and proliferation of the microvessels in the ischemic boundary zone of the cortex were evaluated. Treatment with L-serine (168 mg/kg body weight, i.p.) began 3 h after pMCAO and was repeated every 12 h for 7 days or until the end of the experiment. L-Serine treatment: 1) reduced the lesion volume and neuronal loss; 2) improved the recovery of neurological functions; 3) elevated the expression of nerve growth-related factors; and 4) facilitated the proliferation of endogenous NSCs and microvessels activated after pMCAO and increased the number of new-born neurons. 5) D-cycloserine, an inhibitor of serine hydroxymethyltransferase, blunted the effects of L-serine on NSC proliferation, differentiation, microvascular proliferation. In conclusions, L-serine treatment in pMCAO rats can reduce brain injury and facilitate neurorestoration which is partly associated with the improvement of proliferation of NSCs and microvessels, reconstruction of neurovascular units and resultant neurorepair. The effects of L-serine on endogenous NSC proliferation and microvascular proliferation are partly mediated by the action of L-serine as a substrate for the production of one-carbon groups used for purine and pyrimidine synthesis and modulation of the expression of some nerve growth-related factors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Proliferation
  • Central Nervous System Agents / pharmacology*
  • Central Nervous System Agents / therapeutic use
  • Cerebral Cortex / blood supply
  • Cerebral Cortex / pathology
  • Cerebral Cortex / physiopathology
  • Cerebrovascular Circulation / drug effects
  • Infarction, Middle Cerebral Artery / drug therapy*
  • Infarction, Middle Cerebral Artery / physiopathology
  • Infarction, Middle Cerebral Artery / psychology
  • Male
  • Maze Learning / drug effects
  • Microvessels / drug effects
  • Nerve Regeneration / drug effects*
  • Neural Stem Cells / drug effects
  • Neural Stem Cells / physiology
  • Rats, Sprague-Dawley
  • Serine / pharmacology*
  • Serine / therapeutic use

Substances

  • Central Nervous System Agents
  • Serine

Grants and funding

This work was supported partly by grants from the National Natural Science Foundation of China (81000497, 81071614 and 81372131), by project funding from the Priority Academic Program Development of Jiangsu Higher Education Institutions, and by the Project for Innovation Development of Graduate Student of Nantong University. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.