Effects of Piracetam and Hyperbaric Oxygen on Histopathological and Circulating Biochemical Responses Following Sciatic Nerve Crush Injury in Rats

Background: Peripheral nerve injury initiates a series of degenerative, inflammatory, and reparative responses. Piracetam and hyperbaric oxygen (HBO) have been proposed as potential therapeutic interventions; however, their effects during the early phase following sciatic nerve injury require further investigation. This study evaluated early histopathological and circulating biochemical responses to piracetam and HBO in a rat model of sciatic nerve injury. Methods: Forty male Wistar Albino rats were randomly allocated to four groups following experimental sciatic nerve injury: an untreated injury control group (Group K), a hyperbaric oxygen therapy group (Group HBO), an intraperitoneal piracetam group (Group P), and a combined hyperbaric oxygen plus piracetam group (Group HBO + P). After 14 days, the rats were euthanised, and sciatic nerve tissues and blood samples were collected for histopathological and biochemical analyses. Results: No statistically significant differences were observed among the four groups with respect to axonal continuity, capillary formation, or myelin sheath regeneration. Fibroblast density was increased in Group P compared with Group K (p = 0.025), while no significant differences were detected among the remaining groups. Inflammatory cell counts were higher in Group P than in Group K (p = 0.037) and elevated in Group HBO + P compared with Group K (p = 0.014). Hypoxia-inducible factor-1 alpha (HIF-1α) expression was highest in Group K. Additionally, neuron-specific enolase levels were significantly increased in Group P compared with Group K (p = 0.006). Conclusions: Under the conditions of this 14-day experimental study, piracetam and HBO were associated with differences in selected circulating biochemical parameters but did not produce statistically significant improvements in the assessed histopathological indices. The findings were interpreted as early responses to treatment, and longer follow-up studies are needed to determine whether these changes translate into sustained axonal regeneration or functional recovery.