Neuroprotective effects of celastrol on sciatic nerve transection model in male Wistar rats.

Objectives: Celastrol is an herbal compound with neuroprotective properties. Our research aimed to assess the neuroprotective properties of celastrol on sciatic nerve transection in rats. Materials and Methods: The rats' left sciatic nerve was cut and sutured directly. The animals were then given 1 or 2 mg/kg celastrol intraperitoneally for two weeks. The sensory and locomotor behaviors of the animals were then evaluated for 16 weeks. Immunohistochemistry, ELISA, and real-time PCR were also utilized to evaluate macrophage polarization, cytokine secretion, and neurotrophin expression in injured nerves. Results: Results showed that both doses of celastrol significantly accelerated nerve regeneration and improved sensorimotor functional recovery when compared with controls. Nevertheless, administration of 2 mg/kg of celastrol significantly outperforms treatment with a dose of 1 mg/kg. Celastrol treatment-induced M2 polarization in macrophages decreased proinflammatory cytokines at the injury site. It also increased the expression of BDNF mRNA. Conclusion: These findings suggest that a two-week treatment with celastrol had neuroprotective effects in a rat sciatic nerve transection model, most likely by inducing macrophage M2 polarization and anti-inflammatory effects.