Exendin-4 Plays a Protective Role in a Rat Model of Spinal Cord Injury Through SERCA2

Cell Physiol Biochem. 2018;47(2):617-629. doi: 10.1159/000490017. Epub 2018 May 22.

Abstract

Background/aims: Current therapies for spinal cord injury (SCI) have limited efficacy, and identifying a therapeutic target is a pressing need. Sarcoplasmic/endoplasmic reticulum Ca2+ ATPase 2 (SERCA2) plays an important role in regulating calcium homeostasis, which has been shown to inhibit apoptosis. Exendin-4 has been shown to inhibit the apoptosis of nerve cells in SCI, which can also improve SERCA2 expression. In this study, we sought to determine whether exendin-4 plays a protective role in a rat model of SCI via SERCA2.

Methods: To investigate the effects of exendin-4 on SCI, a rat model of SCI was induced by a modified version of Allen's method. Spinal cord tissue sections from rats and western blot analysis were used to examine SERCA2 expression after treatment with the long-acting glucagon-like peptide 1 receptor exendin-4 or the SERCA2 antagonist 5(6)-carboxyfluorescein diacetate N-succinimidyl ester (CE). Locomotor function was evaluated using the Basso Beattie Bresnahan locomotor rating scale and slanting board test.

Results: Cell apoptosis was increased with CE treatment and decreased with exendin-4 treatment. Upregulation of SERCA2 in female rats with SCI resulted in an improvement of motor function scores and histological changes.

Conclusion: These findings suggest that exendin-4 plays a protective role in a rat model of SCI through SERCA2 via inhibition of apoptosis. Existing drugs targeting SERCA2 may be an effective therapeutic strategy for the treatment of SCI.

Keywords: Apoptosis; Exendin-4; SERCA2; Spinal cord injury(SCI).

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Caspase 3 / metabolism
  • Cyclic AMP / metabolism
  • Cyclic AMP-Dependent Protein Kinases / antagonists & inhibitors
  • Cyclic AMP-Dependent Protein Kinases / metabolism
  • Disease Models, Animal
  • Exenatide
  • Locomotion / drug effects
  • Microscopy, Fluorescence
  • PC12 Cells
  • Peptides / pharmacology*
  • Peptides / therapeutic use
  • Protective Agents / pharmacology*
  • Protective Agents / therapeutic use
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Recovery of Function / drug effects*
  • Sarcoplasmic Reticulum Calcium-Transporting ATPases / antagonists & inhibitors
  • Sarcoplasmic Reticulum Calcium-Transporting ATPases / metabolism*
  • Signal Transduction / drug effects
  • Spinal Cord Injuries / prevention & control
  • Venoms / pharmacology*
  • Venoms / therapeutic use
  • bcl-2-Associated X Protein / metabolism

Substances

  • Atp2a2 protein, rat
  • Peptides
  • Protective Agents
  • Proto-Oncogene Proteins c-bcl-2
  • Venoms
  • bcl-2-Associated X Protein
  • Exenatide
  • Cyclic AMP
  • Cyclic AMP-Dependent Protein Kinases
  • Caspase 3
  • Sarcoplasmic Reticulum Calcium-Transporting ATPases