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

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.