地黄苷 A 对 CLP 诱导的脓毒症大鼠脑功能障碍和 Nrf2/GPX4介导的 铁死亡通路的影响.

Objective: To investigate the effect and mechanism of Rehmannioside A (ReA) on brain dysfunction in cecal ligation and perforation (CLP) -induced sepsis rats. Methods: 56 CLP-induced sepsis rats were randomly divided into CLP group (n=12), CLP+20ReA group (n=11), CLP+40ReA group (n=11), CLP+80ReA group (n=11), and GPX4-IN-3 group (n=11). Ten rats underwent Sham operation as sham group. Rats in Sham group and CLP group were given 1 mL dimethyl sulfoxide (DMSO). Rats in CLP+20ReA group, CLP+40ReA group and CLP+80ReA group were given 1 mL of 20, 40 and 80 mg/kg/d Rehmannioside A, respectively. Rats in GPX4-IN-3 group were simultaneously administrated with 0.5 mL 80 mg/kg/d of Rehmannioside A and 0.5 mL 15 mg/kg/d of the selective inducer of ferroptosis GPX4-IN-3. Each group was given the drug for 3 days. Neural function score and Morris water maze test were used to evaluate brain function. Neuron-specific enolase (NSE) and S100β levels were detected by ELISA. The water content of brain tissue was measured by weighing method. Brain injury was evaluated by HE staining and Nissl staining. The levels of reduced glutathione (GSH) and malondialdehyde (MDA) in brain tissue were detected by micromethods. The levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were measured by ELISA. The content of Fe2+ in brain tissue was determined by micromethod. The levels of nuclear factor E2-related factor 2 (Nrf2), Kelch-like ECH related protein 1 (Keap1) and glutathione peroxidase 4 (GPX4) protein in brain tissue were detected by Western blot. Results: Compared with CLP group, the neural function scores and escape latency of CLP+20ReA group, CLP+40ReA group and CLP+80ReA group decreased (P<0.05), the number of crossing platforms increased (P<0.05), the neuronal damage reduced, the levels of serum NSE and S100β decreased (P<0.05), the level of GSH in brain tissue increased (P<0.05). The water content of brain tissue and levels of MDA, IL-6, TNF-α and the content of Fe2+ in brain tissue decreased(P<0.05), the protein expressions of Nrf2 (nucleus) and GPX4 in brain tissue increased(P<0.05), and the protein expression of Keap1 decreased(P<0.05). Compared with CLP+80ReA group, the brain dysfunction of GPX4-IN-3 group was aggravated, and the Nrf2/GPX4 pathway was inhibited (P<0.05). Conclusion: Rehmannioside A inhibits ferroptosis by activating Nrf2/GPX4 pathway, thereby alleviating brain dysfunction in CLP-induced sepsis rats. [ABSTRACT FROM AUTHOR]