Background Inflammation induced by intracerebral hemorrhage (ICH) is one of the main causes of the high mortality and poor prognosis of patients with ICH. A1 astrocytes are closely associated with neuroinflammation and neurotoxicity, whereas A2 astrocytes are neuroprotective. Homer scaffolding protein 1 (Homer1) plays a protective role in ischemic encephalopathy and neurodegenerative diseases. However, the role of Homer1 in ICH-induced inflammation and the effect of Homer1 on the phenotypic conversion of astrocytes remain unknown. Methods Femoral artery autologous blood from C57BL/6 mice was used to create an ICH model. We use the A1 phenotype marker C3 and A2 phenotype marker S100A10 to detect astrocyte conversion after ICH. Homer1 overexpression/knock-down mice were constructed by adeno-associated virus (AAV) infection to explore the role of Homer1 and its mechanism of action after ICH. Finally, Homer1 protein and selumetinib were injected into in situ hemorrhage sites in the brains of Homer1flox/flox/Nestin-Cre+/− mice to study the efficacy of Homer1 in the treatment of ICH by using a mouse cytokine array to explore the potential mechanism. Results The expression of Homer1 peaked on the third day after ICH and colocalized with astrocytes. Homer1 promotes A1 phenotypic conversion in astrocytes in vivo and in vitro. Overexpression of Homer1 inhibits the activation of MAPK signaling, whereas Homer1 knock-down increases the expression of pathway-related proteins. The Homer1 protein and selumetinib, a non-ATP competitive MEK1/2 inhibitor, improved the outcome in ICH in Homer1flox/flox/Nestin-Cre+/− mice. The efficacy of Homer1 in the treatment of ICH is associated with reduced expression of the inflammatory factor TNFSF10 and increased expression of the anti-inflammatory factors activin A, persephin, and TWEAK. Conclusions Homer1 plays an important role in inhibiting inflammation after ICH by suppressing the A1 phenotype conversion in astrocytes. In situ injection of Homer1 protein may be a novel and effective method for the treatment of inflammation after ICH.

BackgroundInflammation and apoptosis caused by intracerebral hemorrhage (ICH) are two important factors that affect patient prognosis and survival. Toll-like receptor 4 (TLR4) triggers activation of the inflammatory pathway, causing synthesis and release of inflammatory factors. The inflammatory environment also causes neuronal apoptosis. However, no studies have reported the role of TLR4 in inflammation and apoptosis.MethodsWe performed survival curve analysis and behavioral scores on TLR4 knockout mice and wild-type mice after inducing ICH. We used TLR4 knockout mice and wild-type mice to make ICH models with type VII collagenase and explored the link between TLR4 in inflammation and apoptosis. We used Western blot to detect the expression of apoptosis-related proteins, inflammatory factors, and their receptors at different time points after ICH induction. The effects of TLR4 on apoptosis were observed by TUNEL, Hoechst, and HE staining techniques. The association with TLR4 in inflammation and apoptosis was explored using IL-1β and TNF-α antagonists. Data conforming to a normal distribution are expressed as mean ± standard deviation. Grade and quantitative data were compared with rank sum test and t test between two groups. P < 0.05 was considered statistically significant.ResultsTLR4 knockout significantly increased the survival rate of ICH mice. The scores of TLR4 knockout mice were significantly lower than those of wild-type mice. We found that TLR4 knockout mice significantly inhibited apoptosis and the expression of inflammatory factors after the induction of ICH. The apoptosis of ICH-induced mice was significantly improved after injecting IL-1β and TNF-α antagonists. Moreover, the anti-apoptotic effect of the antagonist in wild-type mice is more pronounced. A single injection of the antagonist failed to improve apoptosis in TLR4 knockout mice.ConclusionsWe conclude that TLR4-induced inflammation after ICH promotes neuronal apoptosis. IL-1β and TNF-α antagonists attenuate this apoptotic effect. Therefore, targeting TLR4 in patients with clinical ICH may attenuate inflammatory response, thereby attenuating apoptosis and improving prognosis.

Purpose: Eupatilin is a pharmacologically active flavonoid extracted from Asteraceae argyi that has been identified as having antitumor effects. Gliomas are the most common intracranial malignant tumors and are associated with high mortality and a poor postoperative prognosis. There are few studies on the therapeutic effects of eupatilin on glioma. Therefore, we explored the efficacy and the underlying molecular mechanism of eupatilin on glioma. Methods: The effect of eupatilin on cell proliferation and viability was detected using Cell Counting Kit-8 assays. Cell migration was analyzed with a scratch wound healing assay and invasion was analyzed using transwell assays. Results: We found that eupatilin significantly inhibits the viability and proliferation of glioma cells by arresting the cell cycle at the G1/S phase. In addition, eupatilin disrupts the structure of the cytoskeleton and affects F-actin depolymerization via the “P-LIMK”/cofilin pathway, thereby inhibiting the migration of glioma. We also found that eupatilin inhibits the invasion of gliomas. The underlying mechanism may be related to the destruction of epithelial–mesenchymal transition, with eupatilin also affecting the RECK/matrix metalloproteinase pathway. However, we did not observe the proapoptotic effect of eupatilin on glioma, which is inconsistent with other studies. Finally, we observed a significant inhibitory effect of eupatilin on U87MG glioma in xenograft nude mice. Conclusion: Eupatilin inhibits the viability and proliferation of glioma cells, attenuates the migration and invasion, and inhibits tumor growth in vivo, but does not promote apoptosis. Therefore, due to the poor clinical efficacy of drug treatment of glioma and high drug resistance, the emergence of eupatilin brings a new dawn for glioma patients.