Ferroptosis is a form of oxidative cell death and has become a chemotherapeutic target for cancer treatment. Curcumin (CUR), a well-known cancer inhibitor, significantly inhibits the viability of breast cancer cells. Through transcriptomic analysis and flow cytometry experiments, it was found that after 48 hours of treatment of breast cancer cells at its half maximal inhibitory concentration (IC50), curcumin suppressed the viability of cancer cells via induction of ferroptotic death. Use of the ferroptosis inhibitor ferrostatin-1 and the iron chelator deferoxamine rescued cell death induced by curcumin. Furthermore, in subsequent cell validation experiments, the results showed that curcumin caused marked accumulation of intracellular iron, reactive oxygen species, lipid peroxides, and malondialdehyde, while glutathione levels were significantly downregulated. These changes are all manifestations of ferroptosis. Curcumin upregulates a variety of ferroptosis target genes related to redox regulation, especially heme oxygenase-1 (HO-1). Using the specific inhibitor zinc protoporphyrin 9 (ZnPP) to confirm the above experimental results showed that compared to the curcumin treatment group, treatment with ZnPP not only significantly improved cell viability but also reduced the accumulation of intracellular iron ions and other ferroptosis-related phenomena. Therefore, these data demonstrate that curcumin triggers the molecular and cytological characteristics of ferroptosis in breast cancer cells, and HO-1 promotes curcumin-induced ferroptosis.

Lipopolysaccharide (LPS) is an endotoxin, which may cause immune response and inflammation of bovine mammary glands. Mastitis impairs animal health and results in economic loss. Curcumin (CUR) is a naturally occurring diketone compound, which has attracted widespread attention as a potential anti-inflammatory antioxidant. The purpose of this study is to investigate whether CUR can reduce the damage of bovine mammary epithelial cells (MAC-T) induced by LPS and its underlying molecular mechanism. The MAC-T cell line was treated with different concentrations of LPS and CUR for 24 h. The results showed that CUR rescued the decrease of MAC-T cell viability and cell damage induced by LPS. At the same time, 10 µM CUR and 100 µg/mL LPS were used to treat the cells in the follow-up study. The results showed CUR treatment reduced the accumulation of reactive oxygen species (ROS), the expression of inflammatory cytokines (tumor necrosis factor-a (TNF-α), interleukin-8 (IL-8), IL-6 and IL-1β) and the rate of apoptosis induced by LPS. These effects were associated with the activation of the nuclear factor E2-related factor 2 (NFE2L2)-antioxidant response element (ARE) pathway coupled with inactivation of the nuclear factor-κB (NF-κB) inflammatory and caspase/Bcl2 apoptotic pathways.

Background/Aims: Aberrantly high levels of H3K4me3, caused by incomplete epigenetic reprogramming, likely cause a low efficiency of somatic cell nuclear transfer (SCNT). Smal molecule inhibitors aimed at epigenetic modification can be used to improve porcine SCNT embryo development. In this study, we examined the effects of MM-102, an H3K4 histone methyltransferase inhibitor, on porcine SCNT preimplantation embryos to investigate the mechanism by which H3K4 methylation regulated global epigenetic reprograming during SCNT. Methods: MM-102 was added to the SCNT embryos culture system and the global levels of various epigenetic modifications were measured by immunofluorescence (IF) staining and were quantified by Image J software. Relative genes expression levels were detected by quantitative real-time PCR. Results: MM-102 (75 μM) treatment reduced global H3K4, H3K9 methylation and 5mC levels especially at the zygotic gene activation (ZGA) and blastocyst stages. MM-102 treatment mainly down-regulated a series of DNA and histone methyltransferases, and up-regulated a number of hitone acetyltransferases and transcriptional activators. Furthermore, MM-102 treatment positively regulated the mRNA expression of genes related to pluripotency (OCT4, NANOG, CDX2) and apoptosis (BCL2). Conclusion: Down-regulation of H3K4me3 with MM-102 rescued aberrant gene expression patterns of a series of epigenetic chromatin modification enzymes, pluripotent and apoptotic genes at the ZGA and blastocyst stages, thereby greatly improving porcine SCNT efficiency and blastocyst quality, making them more similar to in vivo embryos (IVV).

Recurrent epidemics of methicillin-resistant Staphylococcus aureus (S. aureus) (MRSA) have illustrated that the effectiveness of antibiotics in clinical application is rapidly fading. A feasible approach is to combine natural products with existing antibiotics to achieve an antibacterial effect. In this molecular docking study, we found that theaflavin (TF) preferentially binds the allosteric site of penicillin-binding protein 2a (PBP2a), inducing the PBP2a active site to open, which is convenient for β-lactam antibiotics to treat MRSA infection, instead of directly exerting antibacterial activity at the active site. Subsequent TMT-labeled proteomics analysis showed that TF treatment did not significantly change the landscape of the S. aureus USA300 proteome. Checkerboard dilution tests and kill curve assays were performed to validate the synergistic effect of TF and ceftiofur, and the fractional inhibitory concentration index (FICI) was 0.1875. The antibacterial effect of TF combined with ceftiofur was better than that of single-drug treatment in vitro. In addition, TF effectively enhanced the activity of ceftiofur in a mouse model of MRSA-induced pneumonia. Our findings provide a potential therapeutic strategy to combine existing antibiotics with natural products to resolve the prevalent infections of multidrug-resistant pathogens.

Zearalenone (ZEA) is a mycotoxin that is mainly produced by Fusarium fungi in food and feed. It causes many adverse effects on mammals, but there is little research on the effects of ZEA on intestinal mucosal immunity and intestinal flora in animals or humans. In this study, we aimed to explore the effects of short-term ZEA exposure on mucosal immunity and the microecological balance of the intestine. We found that the morphological structure of the intestinal mucosa in mice was severely destroyed after ZEA was administered by gavage for one week, and the mRNA expression levels of mucosal β-defensin, Mucin-1, Mucin-2, interleukin-1beta (IL-1β), and tumour necrosis factor-α (TNF-α) and secretory immunoglobulin A (sIgA) levels were significantly increased. In addition, the intestinal microflora was altered by ZEA. Our study showed that ZEA not only caused inflammation of the mucous membrane but also disturbed the microecological balance of the intestine in mice.

Both zearalenone (ZEA) and lipopolysaccharide (LPS) can induce oxidative stress, and even apoptosis in bovine mammary epithelial cells (MAC-T), but not much attention has been given to the synergistic effect of ZEA and LPS. In this study, we treated MAC-T cells with different concentrations of LPS (1, 10, 50, and 100 μg/mL) and ZEA (5, 15, and 30 μM) to induce cell damage. Previous results show that MAC-T cell viability decreases with increasing LPS concentration. Meanwhile, 1 µg/mL LPS and ZEA were selected for combined treatment in subsequent studies. It was found that co-treatment with ZEA and LPS increases the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA), decreases mitochondrial membrane potential (MMP), and superoxide dismutase (SOD), and reduces glutathione (GSH). ZEA and LPS are found to activate endoplasmic reticulum (ER) stress by increasing the expression of glucose-regulated protein 78 kDa (GRP78), activating transcription factor 6 (ATF6) and C/EBP homologous protein (CHOP). It increases cell apoptosis by suppressing the expression of the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2), indicated by up-regulation of Bcl2-associated X protein (Bax) and Cysteinyl aspartate-specific proteinases 3 (caspase-3) expression. The above results suggest that the synergistic effect of ZEA and LPS aggravate cytotoxicity.