Morphological and functional evaluation of 10-HYDROXY-2-decenoic acid's regenerative effect on mouse sciatic nerve CRUSH model

Traumatic injury of peripheral nerves results in loss of motor and sensory functions. It seriously weakens the workforce and decreases the quality of life. 10-hydroxy-2-decenoic acid (10-HDA) is the predominant fatty acid of royal jelly which is known for its neuroprotective effects. We hypothesize that 10-HDA may accelerate regeneration and recovery after crush injury. The 40 mice were randomly assigned to sham group, sciatic nerve crush group, HDA 30 treatment group, and HDA 60 treatment group. The mice (except sham group) were exposed to sciatic nerve crush injury. One hour after injury, the mice were given 0.9% saline solution or 10-HDA (30 and 60 mg/kg) orally through flexible gavage daily for 4 weeks. The functional recovery was evaluated using thermal hyperalgesia, sciatic function index, rotarod, electromyography, and horizontal ladder rung walking tests. Microstructural changes of the crushed sciatic nerve were analyzed using the ImageJ software for immunofluorescence images of neurofilament (NFH), βIII-tubulin (βIII), myelin protein zero (P0), nicotinic acetylcholine receptor (NAR), and S100 protein on the longitudinal section of the sciatic nerve. We observed that 10-HDA significantly recovered motor and sensory functions at two weeks post-injury. Laser scanning confocal microscopy demonstrated that 10-HDA significantly increased regeneration of NFH, βIII, P0, NAR, S100 structures. Especially the 30 mg/kg dosage of 10-HDA showed promising results. In conclusion, 10-HDA has shown to possess a strong therapeutic effect on sciatic nerve crush injury, which is one of the most common models of peripheral nerve injury in mice.