Clinical and Histopathological Effects of Isotretinoin on Neuroregeneration in Experimental Spinal Cord Injury.

Aim: Spinal cord injury is an important problem, and a fully effective treatment for it has not yet been developed. Isotretinoin is a retinoid known for its anti-inflammatory effect. The present study aimed to evaluate whether isotretinoin has a positive impact on neural tissue in post-injury damage. Material and Methods: A total of 36 rats were randomly divided into 6 groups as control, sham, and injury with 14-day 7.5 mg/kg/day, 28-day 7.5 mg/kg/day, 14-day 15 mg/kg/day, and 28-day 15 mg/kg/day isotretinoin groups. Laminectomy was performed and spinal cord injury was produced by using the clip compression technique. Neurological examination was performed on days 1, 7, 14, and 28. After the treatment period, all rats were sacrificed, and their spinal cord samples were collected for histopathological assessment. Results: Groups receiving 7.5 mg/kg/day (p=0.048) and 15 mg/kg/day (p<0.001) isotretinoin showed a significantly increased inclined plane angle on day 14 compared with the sham group. In hematoxylin and eosin, and Luxol fast blue staining, the 28-day isotretinoin of 15 mg/kg/day group and the control group had similar histopathological findings in motor neurons and glial cells. The cleaved caspase 3 expression was significantly diminished in the groups of 28-day isotretinoin 7.5 mg/kg/day, 14-day isotretinoin 15 mg/kg/day, and 28-day isotretinoin 15 mg/kg/day, compared to the sham group, along with the reduction in apoptosis. Conclusion: Isotretinoin reduces neuronal apoptosis, diminishes pathological tissue damage, and improves functional recovery after injury. The observed prominent neuroprotective effects introduce isotretinoin as a promising therapy for spinal cord injury. [ABSTRACT FROM AUTHOR]