Methylprednisolone (MP) is currently the only drug confirmed to exhibit a neuroprotective effect on acute
spinal cord injury (SCI). Vitamin C (VC) is a natural water-soluble antioxidant that exerts neuroprotective
effects through eliminating free radical damage to nerve cells. Bone marrow mesenchymal stem cells
(BMMSCs), as multipotent stem cells, are promising candidates in SCI repair. To evaluate the therapeutic
effects of MP, VC and BMMSCs on traumatic SCI, 80 adult male rats were randomly divided into seven
groups: control, SCI (SCI induction by weight-drop method), MP (SCI induction, followed by administration
of 30 mg/kg MP via the tail vein, once every other 6 hours, for five times), VC (SCI induction, followed
by intraperitoneal administration of 100 mg/kg VC once a day, for 28 days), MP + VC (SCI induction, followed
by administration of MP and VC as the former), BMMSCs (SCI induction, followed by injection of 3
× 106 BMMSCs at the injury site), and BMMSCs + VC (SCI induction, followed by BMMSCs injection and
VC administration as the former). Locomotor recovery was assessed using the Basso Mouse Scale. Injured
spinal cord tissue was evaluated using hematoxylin-eosin staining and immunohistochemical staining. Expression
of transforming growth factor-beta, tumor necrosis factor-alpha, and matrix metalloproteinase-2
genes was determined using real-time quantitative PCR. BMMSCs intervention better promoted recovery
of nerve function of rats with SCI, mitigated nerve cell damage, and decreased expression of transforming
growth factor-beta, tumor necrosis factor-alpha, and matrix metalloproteinase-2 genes than MP and/or
VC. More importantly, BMMSCs in combination with VC induced more obvious improvements. These
results suggest that VC can enhance the neuroprotective effects of BMMSCs against SCI.