UNASSIGNED: The aim of this study was to explore the role and mechanism of ferroptosis in SiO 2-induced cardiac injury using a mouse model.
UNASSIGNED: Male C57BL/6 mice were intratracheally instilled with SiO 2 to create a silicosis model. Ferrostatin-1 (Fer-1) and deferoxamine (DFO) were used to suppress ferroptosis. Serum biomarkers, oxidative stress markers, histopathology, iron content, and the expression of ferroptosis-related proteins were assessed.
UNASSIGNED: SiO 2 altered serum cardiac injury biomarkers, oxidative stress, iron accumulation, and ferroptosis markers in myocardial tissue. Fer-1 and DFO reduced lipid peroxidation and iron overload, and alleviated SiO 2-induced mitochondrial damage and myocardial injury. SiO 2 inhibited Nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream antioxidant genes, while Fer-1 more potently reactivated Nrf2 compared to DFO.
UNASSIGNED: Iron overload-induced ferroptosis contributes to SiO 2-induced cardiac injury. Targeting ferroptosis by reducing iron accumulation or inhibiting lipid peroxidation protects against SiO 2 cardiotoxicity, potentially via modulation of the Nrf2 pathway.

In this study, we evaluated the cancer cell killing activity of koji mold-derived extracts using several solvents. The koji mold lipid extract (KML) exhibited potent cytotoxicity against a human leukemia cell line. Fractionation of the KML via silica gel chromatography revealed the presence of active components in fraction (Fr.) 6. Cytotoxic effects of Fr. 6 were inhibited by the ferroptosis inhibitors, ferrostatin-1 and SRS11-92, and the iron chelator, deferoxamine. Interestingly, ferroptosis inhibitors failed to prevent the KML-induced cell death. Fr. 6 decreased the expression of glutathione peroxidase 4 (GPx4) and increased the level of peroxidized plasma membrane lipids. Furthermore, Fr. 6 decreased the intracellular glutathione levels. Overall, our results suggest that Fr. 6 included in KML induces ferroptosis in HL-60 cells.

Our study aimed to investigate the role of ferroptosis in sevoflurane-induced hearing impairment and explore the mechanism of the microRNA-182-5p (miR-182-5p)/Glutathione Peroxidase 4 (GPX4) pathway in sevoflurane-induced ototoxicity. Immunofluorescence staining was performed using myosin 7a and CtBP2. Cell viability was assessed using the CCK-8 kit. Fe2+ concentration was measured using FerroOrange and Mi-to-FerroGreen fluorescent probes. The lipid peroxide level was assessed using BODIPY 581/591 C11 and MitoSOX fluorescent probes. The auditory brainstem response (ABR) test was conducted to evaluate the hearing status. Bioinformatics tools and dual luciferase gene reporter analysis were used to confirm the direct targeting of miR-182-5p on GPX4 mRNA. GPX4 and miR-182-5p expression in cells was assessed by qRT-PCR and Western blot. Ferrostatin-1 (Fer-1) pretreatment significantly improved hearing impairment and damage to ribbon synapses in mice caused by sevoflurane exposure. Immunofluorescence staining revealed that Fer-1 pretreatment reduced intracellular and mitochondrial iron overload, as well as lipid peroxide accumulation. Our findings indicated that miR-182-5p was upregulated in sevoflurane-exposed HEI-OC1 cells, and miR-182-5p regulated GPX4 expression by binding to the 3\'UTR of GPX4 mRNA. The inhibition of miR-182-5p attenuated sevoflurane-induced iron overload and lipid peroxide accumulation. Our study elucidated that the miR-182-5p/GPX4 pathway was implicated in sevoflurane-induced ototoxicity by promoting ferroptosis.

1,4-cyclohexanedimethylamine (1,4-BAC) is an important monomer for bio-based materials, it finds wide applications in various fields including organic synthesis, medicine, chemical industry, and materials. At present, its synthesis primarily relies on chemical method, which suffer from issues such as expensive metal catalyst, harsh reaction conditions, and safety risks. Therefore, it is necessary to explore greener alternatives for its synthesis. In this study, a two-bacterium three-enzyme cascade conversion pathway was successfully developed to convert 1,4-cyclohexanedicarboxaldehyde to 1,4-cyclohexanedimethylamine. This pathway used Escherichia coli derived aminotransferase (EcTA), Saccharomyces cerevisiae derived glutamate dehydrogenase (ScGlu-DH), and Candida boidinii derived formate dehydrogenase (CbFDH). Through structure-guided protein engineering, a beneficial mutant, EcTAF91Y, was obtained, exhibiting a 2.2-fold increase in specific activity and a 1.9-fold increase in kcat/Km compared to that of the wild type. By constructing recombinant strains and optimizing reaction conditions, it was found that under the optimal conditions, a substrate concentration of 40 g/L could produce (27.4±0.9) g/L of the product, corresponding to a molar conversion rate of 67.5%±2.1%.

Ferroptosis hallmarked by lipid peroxidation and iron homeostasis imbalance is involved in the occurrence and development of various diseases. The plant growth regulator chlormequat chloride (CCC) can contribute to the causality and exacerbation of reproductive disorders. However, the mechanism by which CCC may cause Leydig cell attenuation remains poorly understood. In this study, TM3 Leydig cells were used to investigate the inhibitory effect of CCC on cell growth and its possible mechanism. The results showed that CCC caused apoptosis, pyroptosis, ferroptosis and necroinflammation in TM3 cells. By comparing the effects of ferroptosis inhibitor Ferrostatin-1 (Fer-1) and pan-Caspase inhibitor Z-VAD-FMK (ZVF) on lipid peroxidation and Caspase-mediated regulated cell death (RCD), we found that Fer-1 was better at rescuing the growth of TM3 cells than ZVF. Although ZVF reduced mitochondrial ROS level and inhibited the activation of Caspase3 and Caspase1, it could not significantly ameliorate lipid peroxidation and the levels of IL-1β and HMGB1 like Fer-1. Therefore, ferroptosis might be a key non apoptotic RCD mode responsible for CCC-driven inflammation, leading to weakened viability and proliferation of TM3 cells. In addition, overexpression of ferritin light chain (FTL) promoted the resistance of TM3 cells to CCC-induced ferroptosis-mediated inflammation and to some extent improved the inhibition of viability and proliferation. Altogether, ferroptosis-initiated inflammation might play a key role in CCC-impaired TM3 cell growth.

UNASSIGNED: Keloid is a chronic proliferative fibrotic disease caused by abnormal fibroblasts proliferation and excessive extracellular matrix (ECM) production. Numerous fibrotic disorders are significantly influenced by ferroptosis, and targeting ferroptosis can effectively mitigate fibrosis development. This study aimed to investigate the role and mechanism of ferroptosis in keloid development.
UNASSIGNED: Keloid tissues from keloid patients and normal skin tissues from healthy controls were collected. Iron content, lipid peroxidation (LPO) level, and the mRNA and protein expression of ferroptosis-related genes including solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), transferrin receptor (TFRC), and nuclear factor erythroid 2-related factor 2 (Nrf2) were determined. Mitochondrial morphology was observed using transmission electron microscopy (TEM). Keloid fibroblasts (KFs) were isolated from keloid tissues, and treated with ferroptosis inhibitor ferrostatin-1 (fer-1) or ferroptosis activator erastin. Iron content, ferroptosis-related marker levels, LPO level, mitochondrial membrane potential, ATP content, and mitochondrial morphology in KFs were detected. Furthermore, the protein levels of α-smooth muscle actin (α-SMA), collagen I, and collagen III were measured to investigate whether ferroptosis affect fibrosis in KFs.
UNASSIGNED: We found that iron content and LPO level were substantially elevated in keloid tissues and KFs. SLC7A11, GPX4, and Nrf2 were downregulated and TFRC was upregulated in keloid tissues and KFs. Mitochondria in keloid tissues and KFs exhibited ferroptosis-related pathology. Fer-1 treatment reduced iron content, restrained ferroptosis and mitochondrial dysfunction in KFs, Moreover, ferrostatin-1 restrained the protein expression of α-SMA, collagen I, and collagen III in KFs. Whereas erastin treatment showed the opposite results.
UNASSIGNED: Ferroptosis exists in keloid. Ferrostatin-1 restrained ECM deposition and fibrosis in keloid through inhibiting ferroptosis, and erastin induced ECM deposition and fibrosis through intensifying ferroptosis.

OBJECTIVE: To investigate the effect of nuclear factor E2-related factor 2 (Nrf2) protein on ferroptosis in mice with sepsis-associated liver injury (SALI).
METHODS: he male Sprague-Dawley (SD) mice were divided into 6 groups according to the random number table method, with 6 mice in each group. The SALI model of mice was established by cecal ligation and puncture (CLP), and the Sham group was only treated with laparotomy. CLP+Fer-1 group, CLP+Erastin group, CLP+ML385 group and CLP+Curcumin group were intraperitoneally injected with iron death inhibitor Ferrostatin-1 (Fer-1) 10 mg×kg-1×d-1, iron death activator Erastin 20 mg×kg-1×d-1, Nrf2 inhibitor ML385 30 mg×kg-1×d-1 and Nrf2 activator Curcumin 100 mg×kg-1×d-1 after CLP, respectively; Sham group and CLP group were given normal saline 10 mg×kg-1×d-1, each group was administered continuously for 10 days. Ten days after operation, the serum and liver tissues of mice were collected to detect the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum, and the levels of malondialdehyde (MDA), glutathione (GSH) and Fe2+; in liver homogenate. The pathological changes of liver tissue were observed under light microscope after hematoxylin-eosin (HE) staining. The shape and length of mitochondria in liver cells were observed under transmission electron microscope. The protein expressions of Nrf2, glutathione peroxidase 4 (GPX4) and prostaglandin-endoperoxide synthase 2 (PTGS2) in liver tissue were detected by Western blotting.
RESULTS: Compared with Sham group, the serum levels of ALT and AST in the CLP group were significantly increased; histologically, the hepatic cord was disordered, the cells were swollen and necrotic, and the length of mitochondria was significantly shortened; the levels of MDA and Fe2+ in liver tissue increased significantly, and the content of GSH decreased significantly; the protein expressions of Nrf2 and GPX4 in liver tissue decreased, and the protein expression of PTGS2 increased significantly. Compared with CLP group, the serum levels of ALT and AST in CLP+Fer-1 group and CLP+Curcumin group were significantly decreased [ALT (U/L): 80.65±19.44, 103.45±20.52 vs. 283.50±37.12, AST (U/L): 103.33±11.90, 127.33±15.79 vs. 288.67±36.82, all P < 0.05]; microscopically, the hepatic cord was irregular, the cells were slightly swollen, and the mitochondrial length was significantly increased (μm: 1.42±0.09, 1.43±0.21 vs. 1.07±0.25, both P < 0.05); the levels of MDA and Fe2+; in liver tissue decreased significantly, and the content of GSH increased significantly [MDA (mol/g): 0.87±0.23, 1.85±0.43 vs. 4.47±0.95, Fe2+ (μg/g): 63.80±7.15, 67.48±6.28 vs. 134.52±14.32, GSH (mol/g): 1.95±0.29, 1.95±0.45 vs. 0.55±0.29, all P < 0.05]; the protein expressions of Nrf2 and GPX4 in liver tissue were significantly increased, and the protein expression of PTGS2 was significantly decreased (Nrf2/GAPDH: 1.80±0.28, 2.10±0.43 vs. 0.70±0.24, GPX4/GAPDH: 0.80±0.06, 0.93±0.07 vs. 0.48±0.02, PTGS2/GAPDH: 0.76±0.05, 0.84±0.01 vs. 1.02±0.09, all P < 0.05). However, the results of the above indexes in the CLP+Erastin group and CLP+ML385 group were opposite, and the serum levels of ALT and AST were significantly increased [ALT (U/L): 344.52±40.79, 321.70±21.10 vs. 283.50±37.12, AST (U/L): 333.50±27.90, 333.00±16.67 vs. 288.67±36.82, all P < 0.05]; microscopically, the arrangement of hepatic cords was disordered, the cells were obviously swollen and necrotic, and the length of mitochondria was significantly shortened (μm: 0.78±0.13, 0.67±0.07 vs. 1.07±0.25, both P < 0.05); the levels of MDA and Fe2+ in liver tissue increased significantly, and the content of GSH decreased significantly [MDA (mol/g): 5.92±1.06, 5.62±0.56 vs. 4.47±0.95, Fe2+ (μg/g): 151.40±8.03, 151.88±8.68 vs. 134.52±14.32, GSH (mol/g): 0.25±0.08, 0.23±0.11 vs. 0.55±0.29, all P < 0.05]; the protein expressions of Nrf2 and GPX4 in liver tissue were significantly decreased, and the protein expression of PTGS2 was significantly increased (Nrf2/GAPDH: 0.46±0.09, 0.46±0.11 vs. 0.70±0.24, GPX4/GAPDH: 0.34±0.05, 0.40±0.01 vs. 0.48±0.02, PTGS2/GAPDH: 1.24±0.13, 1.16±0.11 vs. 1.02±0.09, all P < 0.05).
CONCLUSIONS: CLP-induced SALI can lead to ferroptosis in mice hepatocytes, and Nrf2 protein in liver tissue can mediate SALI by regulating ferroptosis.

OBJECTIVE: Polydopamine nanoparticles (PDA NPs) are a promising topic in the fields of drug delivery, tissue engineering, bioimaging, etc. The present study aims to explore the impact of PDA NPs carrying ferroptosis inhibitor ferstatin-1 (Fer-1) on myocardial ischemia-reperfusion injury (MIRI).
METHODS: After establishment of a rat model of MIRI and PDA NPs, the rats were divided into 4 groups: model group, sham operation group, Fer-1 group, and nano+Fer-1 group (n=8). To detect the effect of PDA NPs encapsulating Fer-1 on ferroptosis in MIRI rats, we further set up NOX4 overexpression group (pc-NOX4 group), NOX4 inhibitor group (Fulvene-5 group), nano+Fer-1+pc-NOX4 group, and nano+Fer-1+Fulvene-5 group (n=8). A CCK-8 assay was conducted to assess cell viability and staining to detect cardiomyocyte apoptosis and observe myocardial infraction.
RESULTS: PDA NPs loaded with Fer-1 were successfully prepared with good safety and biocompatibility. Administration of PDA NPs carrying Fer-1 notably alleviated myocardial injury and hindered the process of ferroptosis in MIRI rats when inducing downregulation of NOX4 expression. Additionally, overexpression of GPX4 significantly attenuated myocardial injury in MIRI rats. While Fer-1 was shown to inhibit the expression of NOX4, the NOX4 inhibitor Fulvene-5 greatly elevated GPX4 and FTH1 expression in cardiomyocytes, and down-regulated the content of Fe2+, especially in the nanometer+Fer-1+Fulvene-5 group.
CONCLUSIONS: With promising safety and biocompatibility, PDA NPs encapsulated Fer-1 decrease GPX4 and FTH1 expression by inhibiting the level of NOX4 in myocardial cells of MIRI rats, thereby suppressing ferroptosis of cardiomyocytes and alleviating myocardial injury.

Developing novel chiral stationary phases (CSPs) with versatility is of great importance in enantiomer separation. This study fabricated a dual-chiral covalent organic framework (PA-CA COF) via successive post-synthetic modifications. The chiral trans-1,2-cyclohexanediamine (CA) and (D)-penicillamine (PA) groups were periodically aligned within nanochannels of the COF, allowing selective recognition of enantiomers through intermolecular interactions. It can be a versatile high-performance liquid chromatography (HPLC) CSP for separating a wide range of enantiomers, including chiral pharmaceutical intermediates and chiral drugs. With separation performance comparable to commercial chiral columns and even greater versatility, the PA-CA COF@SiO2 column held promise for practical applications. Chiral separation results combined with molecular simulation indicated that the mixed mode of PA and CA resulted in the broad separation capability of PA-CA COF. The introduction of the dual-chiral COFs concept opens up a new avenue for chiral recognition and separation, holding great potential for practical enantiomer separation.

Manganese (Mn) overexposure has been associated with the development of neurological damage reminiscent of Parkinson\'s disease, while the underlying mechanisms have yet to be fully characterized. This study aimed to investigate the mechanisms leading to injury in dopaminergic neurons induced by Mn and identify novel treatment approaches. In the in vivo and in vitro models, ICR mice and dopaminergic neuron-like PC12 cells were exposed to Mn, respectively. We treated them with anti-ferroptotic agents ferrostatin-1 (Fer-1), deferoxamine (DFO), HIF-1α activator dimethyloxalylglycine (DMOG) and inhibitor LW6. We also used p53-siRNA to verify the mechanism underlying Mn-induced neurotoxicity. Fe and Mn concentrations increased in ICR mice brains overexposed to Mn. Additionally, Mn-exposed mice exhibited movement impairment and encephalic pathological changes, with decreased HIF-1α, SLC7A11, and GPX4 proteins and increased p53 protein levels. Fer-1 exhibited protective effects against Mn-induced both behavioral and biochemical changes. Consistently, in vitro, Mn exposure caused ferroptosis-related changes and decreased HIF-1α levels, all ameliorated by Fer-1. Upregulation of HIF-1α by DMOG alleviated the Mn-associated ferroptosis, while LW6 exacerbated Mn-induced neurotoxicity through downregulating HIF-1α. p53 knock-down also rescued Mn-induced ferroptosis without altering HIF-1α protein expression. Mn overexposure resulted in ferroptosis in dopaminergic neurons, mediated through the HIF-1α/p53/SLC7A11 pathway.