Propofol Suppresses Ferroptosis via Modulating eNOS/NO Signaling Pathway to Improve Traumatic Brain Injury

Purpose

This study aims to explore the neuroprotective effect of propofol in improving traumatic brain injury (TBI) by inhibiting ferroptosis through the modulation of the endothelial nitric oxide (NO) synthase (eNOS)/NO signaling pathway.

Methods

The GSE173975 dataset was used to analyze the differentially expressed genes between TBI and sham surgery control groups in the short and long term. A TBI model was established in 2-month-old male SPF C57BL/6 mice by impact exposure of the exposed dura mater. After the establishment of the TBI model, propofol (30 mg/kg) or saline was administered via intraperitoneal injection for intervention. Nissl staining and Perls staining were employed to assess neuronal function and iron deposition, respectively. Western blot technology was employed to detect the expression of proteins related to ferroptosis. Immunofluorescence staining of astrocytes and microglia was utilized to assess the neuroinflammatory response induced by TBI. The Morris water maze (MWM) and novel object recognition (NOR) tests were employed to assess cognitive dysfunction induced by TBI.

Findings

Bioinformatics analysis revealed aberrant gene expression associated with iron transport, neuronal death, and inflammatory response in the initial stages of TBI. Long-term abnormalities were predominantly linked to genes involved in inflammatory response. Perls staining and protein expression analysis confirmed the occurrence of iron deposition and ferroptosis following TBI. Propofol treatment significantly reduced iron deposition and ferroptosis induced by TBI. Nissl staining demonstrated enhanced neuronal function, while TUNEL staining indicated reduced neuronal apoptosis. Immunofluorescence analysis demonstrated that propofol significantly reduced the proliferation of astrocytes and activation of microglia induced by TBI in the long term. The results of MWM and NOR tests indicated that propofol significantly improved the long-term cognitive dysfunction induced by TBI. Propofol exerts neuroprotective effects by increasing the expression of eNOS protein and the content of NO. The neuroprotective effects of propofol can be reversed by the eNOS inhibitor L-NAME.

Conclusion

Propofol significantly improves the prognosis of TBI by inhibiting ferroptosis through the modulation of the eNOS/NO signaling pathway. The study results provide a scientific basis for the clinical use of propofol as a neuroprotective agent and offer a new direction for the development of new treatment strategies for TBI.