Background/Objectives: Diabetes mellitus is known to exacerbate neural degeneration and impair regenerative capacity following injury. This study aimed to investigate the effects of Garcinia kola and curcumin on spinal cord morphology and neural structure in a diabetic sciatic nerve injury model. Methods: Spinal cord tissues were obtained from male Wistar albino rats subjected to sciatic nerve transection and diabetes induction in a previously established experimental model. Animals had been assigned to five experimental groups (n = 7 per group): control group, transected sciatic nerve group, transected sciatic nerve + diabetes mellitus (DM), transected sciatic nerve + diabetes mellitus + curcumin (DM + Cur), and transected sciatic nerve + diabetes mellitus + Garcinia kola (DM + GK). Curcumin (300 mg/kg/day) and Garcinia kola (200 mg/kg/day) were administered orally. All animals were sacrificed at three months post-injury. Cervical (C3–C5) spinal cord segments were processed for histological evaluation, and quantitative assessments were performed using unbiased stereological methods to estimate neuronal and structural parameters. Microscopic analyses were conducted to assess morphological alterations. Results: Diabetes combined with sciatic nerve transection induced marked structural alterations in the spinal cord, including reductions in neuronal density and disruption of tissue organization. The DM group showed a significantly lower number of motor neurons than the other groups; similarly, it showed a significant decrease in soma area compared to the Cont and Sham groups. Conclusions: Both the curcumin and Garcinia kola treatment groups exhibited partial preservation of spinal cord morphology. This study provides evidence that Garcinia kola and curcumin exert protective effects not only at the peripheral nerve level, but also in the spinal cord following diabetic nerve injury.