Spinal cord injury (SCI) can cause various symptoms, including
pain, complete or incomplete loss of autonomic, sensory, motor and functions inferior to the site of the damage. Despite wondrous advances in medicine, treating
spinal cord injuries remains a thorny issue yet. Recently, the control of inflammatory processes after damage to the nervous system has been noticed as a promising therapeutic target. The goal of the present experiment was to identify the effects of
apelin-13 on the histological outcome, inflammatory factors, and functional recovery in the animal
contusion model of SCI were analyzed. 40 Female Wistar rats were randomly but equally assigned in
laminectomy,
contusion, PBS (1 mL PBS, i.p), control group which received
apelin-13 (control +
apelin, 100 μg/kg, i.p), and
apelin-13 treatment groups. In the treatment group,
apelin-13 (100 μg/kg) was injected intraperitoneally 30 min after injury. The weight-dropping
contusion model was used for inducing SCI. The Basso, Beattie, and Bresnahan scale (BBB), narrow beam test (NBT), rotarod test, and the open-field test was applied to evaluate locomotor and behavioral activity. Real-time polymerase chain reaction (PCR) and ELISA technique was accomplished eight weeks after inducing SCI to measure the level of
fibroblast growth factor FGF-1, FGFR1 and the inflammatory factors including
interleukin (IL)-1β,
tumor necrosis factor-α (TNF-α),
IL-6, and
IL-10. Furthermore, histological change was estimated by H&E staining. Our results showed that
apelin-13 treatment after SCI led to a significant increase in functional recovery and behavioral tests. Stereological estimation illustrated that
apelin-13 could reduce significantly central cavity volume and number of glial cells, and also increase significantly spinal cord volume and number of neural cells. PCR and ELISA evaluation shows a significant increase in
IL-10 level and decrease in levels of
FGF-1, FGF-R1, and pro-inflammatory
cytokines (PIC). This study suggested that
apelin-13 has
neuroprotective effects by regulating the inflammatory process after SCI.