L‐F001, a multifunctional fasudil–lipoic acid dimer, antagonizes hypoxic–ischemic brain damage by inhibiting the TLR4/MyD88 signaling pathway.

Introduction: Neonatal hypoxic–ischemic brain damage (HIBD) is a serious inflammatory injury. At present, the standard treatment for this disease is hypothermia therapy, and the effect of drug intervention is still limited. L‐F001 is a compound of fasudil and lipoic acid. Previous in vitro experiments have confirmed that L‐F001 has anti‐inflammatory neuroprotective functions. However, its therapeutic effect on neonates with HIBD remains unknown. This study was aimed at exploring the therapeutic effect of L‐F001 on HIBD rats. Methods: The newborn rats were divided into three groups: Sham operation group, HIBD group, and HIBD + L‐F001 group. HE staining, Nissil staining, the immunofluorescence of iNOS and COX‐2, ELISA (IL‐1β, IL‐6, TNF‐α, and IL‐10), and western blotting analyses were performed to determine the therapeutic effect of L‐F001. Finally, we evaluated the growth and development of each group by measuring body weight. Results: The hippocampal structure of HIBD rats was disordered, and the Nissil body was small and shallow. The expressions of iNOS and COX‐2 in HIBD rats were increased, whereas the expressions of IL‐1β, IL‐6, and TNF‐α in plasma were upregulated, and the expression of IL‐10 was decreased. L‐F001 could improve the tissue structure and reduce the expression of iNOS and COX‐2 in HIBD rats. Meanwhile, L‐F001 could also reduce the expression of pro‐inflammatory cytokines and restore the content of anti‐inflammatory cytokines in plasma. We further found that the TLR4 pathway was activated after hypoxic‐ischemia in neonatal rats. L‐F001 could inhibit the activation of TLR4 pathway. Finally, we found that after L‐F001 treatment, the body weight of HIBD rats increased significantly compared with the untreated group. Conclusions: L‐F001 antagonizes the inflammatory response after hypoxic‐ischemia by inhibiting the activation of the TLR4 signaling pathway, thus playing a neuroprotective role. L‐F001 may be a potential therapeutic agent for neonatal HIBD. [ABSTRACT FROM AUTHOR]