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Extracellular histones have been determined as important mediators of sepsis, which induce excessive inflammatory responses in macrophages and impair innate immunity. Magnesium (Mg 2+ ), one of the essential nutrients of the human body, contributes to the proper regulation of immune function. However, no reports indicate whether extracellular histones affect survival and bacterial phagocytosis in macrophages and whether Mg 2+ is protective against histone-induced macrophage damage. Our clinical data revealed a negative correlation between circulating histone and monocyte levels in septic patients, and in vitro experiments confirmed that histones induced mitochondria-associated apoptosis and defective bacterial phagocytosis in macrophages. Interestingly, our clinical data also indicated an association between lower serum Mg 2+ levels and reduced monocyte levels in septic patients. Moreover, in vitro experiments demonstrated that Mg 2+ attenuated histone-induced apoptosis and defective bacterial phagocytosis in macrophages through the PLC/IP3R/STIM-mediated calcium signaling pathway. Importantly, further animal experiments proved that Mg 2+ significantly improved survival and attenuated histone-mediated lung injury and macrophage damage in histone-stimulated mice. Additionally, in a cecal ligation and puncture (CLP) + histone-induced injury mouse model, Mg 2+ inhibited histone-mediated apoptosis and defective phagocytosis in macrophages and further reduced bacterial load. Overall, these results suggest that Mg 2+ supplementation may be a promising treatment for extracellular histone-mediated macrophage damage in sepsis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Sorafenib resistance is becoming increasingly common and disadvantageous for hepatocellular carcinoma (HCC) treatment. Ferroptosis is an iron dependent programmed cell death underlying the mechanism of sorafenib. Iron is crucial for synthesis of cofactors essential to mitochondrial enzymes and necessary for HCC proliferation, while mitochondrial iron overload and oxidative stress are associated with sorafenib induced ferroptosis. However, the crosstalk among iron homeostasis and sorafenib resistance is unclear. Methods: We conducted bioinformatics analysis of sorafenib treated HCC datasets to analyze GCN5L1 and iron related gene expression with sorafenib resistance. GCN5L1 deleted HCC cell lines were generated by CRISPR technology. Sorafenib resistant HCC cell line was established to validate dataset analysis and evaluate the effect of potential target. Results: We identified GCN5L1, a regulator of mitochondrial acetylation, as a modulator in sorafenib-induced ferroptosis via affecting mitochondrial iron homeostasis. GCN5L1 deficiency significantly increased sorafenib sensitivity in HCC cells by down-regulating mitochondrial iron transporters CISD1 expression to induce iron accumulation. Mitochondrial iron accumulation leads to an acceleration in cellular and lipid ROS. Sorafenib resistance is related to CISD1 overexpression to release mitochondrial iron and maintaining mitochondrial homeostasis. We combined CISD1 inhibitor NL-1 with sorafenib, which significantly enhanced sorafenib-induced ferroptosis by promoting mitochondrial iron accumulation and lipid peroxidation. The combination of NL-1 with sorafenib enhanced sorafenib efficacy in vitro and in vivo. Conclusions: Our findings demonstrate that GCN5L1/CISD1 axis is crucial for sorafenib resistance and would be a potential therapeutic strategy for sorafenib resistant HCC. [ABSTRACT FROM AUTHOR]

Objective. Ferroptosis, a form of programmed cell death, is considered a novel target for the treatment of ulcerative colitis (UC). The aim of this study was to explore whether modified Gegen Qinlian decoction (MGQD) ameliorates UC in mice via mediating ferroptosis. Methods. Mice with dextran sulfate sodium- (DSS-) induced colitis were administered with MGQD for seven days. Subsequently, iron, malondialdehyde (MDA), glutathione (GSH), and reactive oxygen species (ROS) were measured. ELISA and immunohistochemistry were used to evaluate the levels of proinflammatory cytokines and tight junction proteins, respectively. Transmission electron microscopy was used to reveal mitochondrial morphology. Western blot and qRT-PCR analyses were used to assess the expression levels of the proteins of Nrf2/GPX4 pathway. The docking affinity of MGQD and Nrf2 was assessed using AutoDock Vina 1.1.2. Results. Ferroptosis was identified in mice with UC, as demonstrated by mitochondrial disruption, MDA and ROS production, iron overload, decrease in GSH level, and abnormal expression of core marker proteins of ferroptosis. After MGQD treatment, these characteristic changes of ferroptosis were significantly reversed, along with concomitant activation of the Nrf2/GPX4 pathway. Furthermore, molecular docking analysis revealed that MGQD had a high affinity for Nrf2. Conclusion. MGQD may ameliorate UC by inhibiting ferroptosis via the activation of Nrf2/GPX4 pathway. This study provided new insights into the application of MGQD complementary therapy for UC. [ABSTRACT FROM AUTHOR]