Curcumin Alleviates Microglia-Mediated Neuroinflammation and Neuronal Ferroptosis Following Experimental Subarachnoid Hemorrhage by Modulating the Nrf2/HO-1 Signaling Pathway.

Abstract

Early brain injury caused by subarachnoid hemorrhage (SAH) is associated with inflammatory response and ferroptosis. Curcumin alleviates neuroinflammation and oxidative stress by as yet unknown neuroprotective mechanisms. The objective of this study was to investigate the impact of curcumin on neuronal ferroptosis and microglia-induced neuroinflammation following SAH. By examining Nrf2/HO-1 expression levels and ferroptosis biomarkers expression both in vitro and in vivo, it was demonstrated that curcumin effectively suppressed ferroptosis in neurons after SAH through modulation of the Nrf2/HO-1 signaling pathway. Furthermore, by analyzing the expression levels of Nrf2, HO-1, p-p65, and inflammation-related genes, it was confirmed that curcumin could prevent the upregulation of pro-inflammatory factors following SAH by regulating the Nrf2/HO-1/NF-κB signaling pathway in microglia. The ability of curcumin to reduce neuronal damage and cerebral edemas after SAH in mice was validated using TUNEL staining, Nissl staining, and measurement of brain tissue water content. Additionally, through implementation of the modified Garcia test, open field test, and Y-maze test, it was established that curcumin ameliorated neurobehavioral impairments in mice post-SAH. Taken together, these data suggest that curcumin may offer a promising therapeutic approach for improving outcomes following SAH by concurrently attenuating neuronal ferroptosis and reducing neuroinflammation.