GPX1 Expression Research Articles

An integrative analysis of ASCL1 in breast cancer and inhibition of ASCL1 increases paclitaxel sensitivity by activating ferroptosis via the CREB1/GPX4 axis

ObjectiveOur previous study found that Achaete-scute complex homolog 1 (ASCL1) is involved in classifying BC subtypes with different prognostic and pathological characteristics. However, the biological role of ASCL1 in BC still remains largely unexplored. This study aims to elucidate the function of ASCL1 in BC using bioinformatics analyses, as well as in vitro and in vivo experimental approaches.MethodsData from the TCGA, GEO, and Human Protein Atlas databases were utilized to evaluate ASCL1 expression in BC and its association with patient prognosis. Genetic alterations in ASCL1 were assessed through the COSMIC and cBioPortal databases, while the TIMER2.0 database provided insights into the relationship between ASCL1 expression and key gene mutations in BC. The GDSC database was used to examine correlations between ASCL1 levels and sensitivity to standard chemotherapeutic agents. Associations between ASCL1 expression and cytokines, immunomodulatory factors, MHC molecules, and receptors were analyzed using Pearson and Spearman correlation methods. The TIP database was employed to investigate the connection between ASCL1 expression and immunoreactivity scores, and six computational approaches were applied to evaluate immune cell infiltration. Functional assays were conducted on BC cell lines MCF-7 and MDA-MB-231, and nude mouse models were used for in vivo studies.ResultsASCL1 was found to be upregulated in BC and correlated with unfavorable prognosis and mutations in key oncogenes. Its expression was linked to immunomodulatory factors, immune cell infiltration, and immunoreactivity scores in the tumor microenvironment. Additionally, ASCL1 influenced tumor immune dynamics and chemosensitivity in BC. Overexpression of ASCL1 enhanced BC cell proliferation, migration and invasion, while its knockdown had the opposite effect. Notably, inhibition of ASCL1 increased BC cell sensitivity to paclitaxel both in vitro and in vivo. In addition, inhibition of ASCL1 activated ferroptosis in BC, including altered mitochondrial morphology, increased MDA and ROS levels, decreased GSH levels and reduced GSH/GSSG ratio. Mechanistically, inhibition of ASCL1 decreases the phosphorylation of CREB1, thus reducing the expression of GPX4. In summary, inhibition of ASCL1 increases paclitaxel sensitivity by activating ferroptosis via the CREB1/GPX4 axis.ConclusionsASCL1 exerts oncogenic effects in BC and represents a potential therapeutic target for intervention.

GPX3 Overexpression Ameliorates Cardiac Injury Post Myocardial Infarction Through Activating LSD1/Hif1α Axis.

Myocardial infarction (MI) often results in significant loss of cardiomyocytes (CMs), contributing to adverse ventricular remodelling and heart failure. Therefore, promoting CM survival during the acute stage of MI is crucial. This study aimed to investigate the potential role of GPX3 in cardiac repair following MI. First, plasma GPX3 levels were measured in patients with acute MI (AMI), and myocardial GPX3 expression was assessed in a mouse MI model. Furthermore, the effects of GPX3 on MI were investigated through CM-specific overexpression or knockdown invitro and invivo models. RNA sequencing and subsequent experiments were performed to uncover the molecular mechanisms underlying GPX3-related effects. Multi-omics database analysis and experimental verification revealed a significant upregulation of GPX3 expression in ischemic myocardium following MI and in CMs exposed to oxygen-glucose deprivation (OGD). Immunofluorescence results further confirmed elevated cytoplasmic GPX3 expression in CMs under hypoxic conditions. Invitro, GPX3 overexpression mitigated reactive oxygen species (ROS) production and enhanced CM survival during hypoxia, while GPX3 knockdown inhibited these processes. Invivo, CM-specific GPX3 overexpression in the infarct border zone significantly attenuated CM apoptosis and alleviated myocardial injury, promoting cardiac repair and long-term functional recovery. Mechanistically, GPX3 overexpression upregulated LSD1 and Hif1α protein expression, and rescue experiments confirmed the involvement of the LSD1/Hif1α pathway in mediating the protective effects of GPX3. Overall, our findings suggest that GPX3 exerts a protective role in ischemic myocardium post-MI, at least partially through the LSD1/Hif1α axis, highlighting its potential as a therapeutic target for MI treatment.

The potential of supplementing compound organic trace elements at lower levels in Chinese yellow- feathered broiler diets, part II: Impacts on growth performance, gut health, intestinal microbiota, and fecal mineral excretion.

This study aimed to investigate the effects of reducing inorganic trace minerals (ITM) by supplementing compound organic trace minerals (OTM) chelates on growth performance, fecal mineral excretion, intestinal health, and cecal microbiota of yellow-feathered broilers. A total of 960 one day old male broilers were randomly assigned to 6 treatments, among which birds were fed with the basal diets (negative control, NC), or supplemented with 1,000 mg/kg (positive control, PC), 300, and 500 mg/kg ITM or OTM, respectively. Dietary supplementation of OTM significantly increased the average daily gain (ADG) during 22-53 d and 1-53 d, and reduced the fecal emissions of Fe, Cu, Zn, and Mn of Chinese yellow-feathered broilers (P < 0.05). Furthermore, the OTM300 group significantly reduced the crypt depth in the duodenum, and increased the ratio of villus height to crypt depth (V/C) in the duodenum and jejunum (P < 0.05). The mRNA expression of TGF-β, Bcl-2, CAT, and GPX4 as well as tight junction proteins (occludin, ZO-1, claudin-1, and claudin-5) in jejunum mucosa were significantly increased by compound OTM when comparing with ITM300 group (P < 0.05). Moreover, dietary compound OTM significantly changed the Chao1 index and β diversity index of cecal microbiota of Chinese yellow-feathered broilers. The abundances of Firmicutes (phylum), Eubacterium_coprostanoligenes_group (family) and Oscillibacter (genus) were increased, while the abundances of Bacteroidetes (phylum) and Rikenellaceae RC9 group (genus) were decreased by OTM treatment. Spearman correlation analysis showed that the mRNA of occludin and jejunal V/C ratio were positively correlated with the abundance of Firmicutes (phylum), but negatively correlated with the abundance of Bacteroidota (phylum). In addition, the abundance of Eubacterium_coprostanoligenes_group (family) was positively correlated with the mRNA of claudin-1, Bcl-2, and TGF-β. PICRUST prediction of microbial function revealed that OTM treatment enriched the pathways related to amino acid metabolism and DNA replication. In conclusion, dietary supplementation at lower levels of compound OTM to replace ITM could improve growth performance and intestinal health, and reduce the fecal excretion of trace elements by modulation of cecal microbiota community and diversity in Chinese yellow-feathered broilers.

Copper excess induces autophagy dysfunction and mitochondrial ROS-ferroptosis progression, inhibits cellular biosynthesis of milk protein and lipid in bovine mammary epithelial cells.

Excessive copper (Cu) has the potential risk to ecosystems and organism health, with its impact on dairy cow mammary glands being not well-defined. This study used a bovine mammary epithelial cell (MAC-T) model to explore how copper excess affects cellular oxidative stress, autophagy, ferroptosis, and protein and lipid biosynthesis in milk. Results showed the increased intracellular ROS, MDA, and CAT (P < 0.05), alongside decreased T-SOD and GSH in CuSO4-treated cells (P < 0.05). Transmission electron microscopy and Ad-mCherry-GFP-LC3B assays revealed significant autophagosome accumulation in CuSO4 exposed cells (P < 0.05). Additionally, CuSO4 exposure modulated autophagy markers, evidenced by upregulation of genes such as LC3, ATG5, JNK1, and Beclin1, and downregulation of genes such as ATG4B, and p62 (P < 0.05). CuSO4 also led to notable mitochondrial changes, including size reduction, membrane rupture, and cristae loss, and reduced expression of the ferroptosis inhibitor GPX4 (P < 0.05). The expression of mTOR, HIF-1α and β-catenin signaling pathway were inhibited in differentiated MAC-T cells by CuSO4 exposure (P < 0.05), activated autophagy through activation of the AMPK-mTOR pathway which in turn affected downstream levels of genes related to milk protein and lipid. In conclusion, excessive copper induces oxidative stress in MAC-T cells, promoting autophagy through JNK-Bcl2, Beclin1-Vps34 and AMPK-mTOR pathways, leading to cell ferroptosis, as well as inhibits the cellular biosynthesis of milk protein and lipid.

Copper exposure induces neurotoxicity through ferroptosis in C. elegans.

Copper, as a vital trace element and ubiquitous environmental pollutant, exhibits a positive correlation with the neurodegenerative diseases. Recent studies have highlighted ferroptosis's significance in heavy metal-induced neurodegenerative diseases, yet its role in copper-related neurotoxicity remains unclear. This study aimed to investigate the role of ferroptosis in copper-induced neurotoxicity. Previously, we established that copper induced motor behaviors inhibition and neuronal degeneration through oxidative stress in Caenorhabditis elegans (C. elegans). This study revealed that the behavior inhibition (head thrash, body bends, pumping frequency and defecation interval) and neuronal degeneration (GABAergic neurons and dopaminergic neurons) in copper-treated nematodes were reversed by the ferroptosis inhibitor Fer-1. Additionally, copper treatment increased the Fe2+ level and MDA content, and decreased GSH content, suggesting copper activated the ferroptosis in C. elegans. Furthermore, studies found that copper exposure altered the expression of ferroptosis-related genes gpx-1, ftn-1, and acs-17 in C. elegans. The results showed RNAi of gpx-1 and RNAi of ftn-1 significantly promoted Cu-induced neurotoxicity, while the RNAi of acs-17 appeared to rescue the Cu-induced ferroptosis and neurotoxicity. In conclusion, Cu might induce behavior inhibition and neuronal degeneration through ferroptosis in C. elegans. The findings of this study provided new insights in the mechanisms underlying Cu-induced neurotoxicity.

Macrophage metabolic reprogramming ameliorates diabetes-induced microvascular dysfunction

Macrophages play an important role in the development of vascular diseases, with their homeostasis closely linked to metabolic reprogramming. This study aims to explore the role of circular RNA-mediated epigenetic remodeling in maintaining macrophage homeostasis during diabetes-induced microvascular dysfunction. We identified a circular RNA, circRNA-sperm antigen with calponin homology and coiled-coil domains 1 (cSPECC1), which is significantly up-regulated in diabetic retinas and in macrophages under diabetic stress. cSPECC1 knockdown in macrophages attenuates M1 macrophage polarization and disrupts macrophage-endothelial crosstalk in vitro. cSPECC1 knockdown in macrophages mitigates diabetes-induced retinal inflammation and ameliorates retinal vascular dysfunction. Mechanistically, cSPECC1 regulates GPX2 expression by recruiting eIF4A3, enhancing GPX2 mRNA stability and altering arachidonic acid metabolism. The metabolic intermediate 12-HETE has emerged as a key mediator, regulating both macrophage homeostasis and the crosstalk between macrophages and endothelial cells. Exogenous 12-HETE supplementation interrupts the anti-angiogenic effects of cSPECC1 knockdown. Collectively, circSPECC1 emerges as a novel regulator of macrophage-mediated vascular integrity and inflammation. Targeting the metabolic reprogramming of macrophages presents a promising therapeutic strategy for mitigating diabetes-induced vascular dysfunction.

Ginkgetin enhances breast cancer radiotherapy sensitization by suppressing NRF2-HO-1 axis activity.

Breast cancer (BC) is a critical threat to women's lives. Radiotherapy (RT) is a pivotal treatment modality for BC, but the failure of RT due to radioresistance is still not well facilitated. Ginkgetin (GK) has a potent anti-tumor activity intimately associated with ferroptosis. This study applied in vitro and in vivo experimental models to ascertain the GK mechanism of action on BC radioresistance. The outcomes reported that GK could inhibit BC cell growth and increase apoptosis. In addition, when BC cells generated radioresistance, GK promoted ferroptosis of radioresistant BC cells by mitigating NRF2 expression, suppressing HO-1 and NQO1 expression, increasing the intracellular content of reactive oxygen species (ROS) and ferrous ions, accelerating the glutathione (GSH) depletion, and decreasing GPX4 expression. Notably, GK can damage intracellular mitochondria and cause a substantial increase in ferrous ions in BC cells. Therefore, GK shows immense potential for enhancing breast cancer radiotherapy sensitivity, which may provide pivotal evidence for subsequent RT sensitization.

GPX4 expression changes in proximal tubule cells highlight the role of ferroptosis in IgAN

As an important mechanism of renal injury, oxidative stress (OS) is inseparable from the occurrence of renal fibrosis and the rapid progression of renal failure. However, the contribution of OS to IgA nephropathy (IgAN), the primary driver of chronic kidney disease remains uncertain. To investigate the effects of OS in IgAN, and identify the mechanisms of cell and tissue injury and protection, single-cell RNA sequencing (scRNA-seq) data and microarray data of IgAN were collected and analyzed. Through gene set variation analysis (GSVA), we identified significant alterations in the activity of multiple OS pathways within the proximal tubule cells (PTCs) of IgAN patients. Subsequent enrichment analysis revealed that the differentially expressed genes associated with OS in PTCs were primarily linked to the process of ferroptosis. Therefore, regulators of ferroptosis were collected to define the ferroptosis activity of PTCs in IgAN, and we found that the activity of suppressing ferroptosis was significantly enhanced. Moreover, being the central controller of ferroptosis, the expression of GPX4 in the PTCs of IgAN is extremely significant, which has been further verified by immunohistochemistry in kidney tissues of IgAN patients. Additionally, the GSVA of microarray data of IgAN indicated that the activity of driving ferroptosis and suppressing ferroptosis in tubulointerstitium were markedly decreased, however, the inhibition of ferroptosis in the tubulointerstitium of IgAN is relatively stronger. These findings demonstrate that ferroptosis inhibition may be a potential mechanism to alleviate OS injury in IgAN, and GPX4 could not only function as a specific marker for PTCs in IgAN but also represent a potential therapeutic target to halt the progression of the disease.

Incorporation of red macroalgae (Galaxaura oblongata) in roach (Rutilus rutilus) fingerling diet: Effects on growth, immunity, oxidative status and intestinal health.

This study investigates the effects of the red macroalgae Galaxaura oblongata diet supplementation on roach (Rutilus rutilus) fingerlings growth and gene expression related to immunity, the intestinal barrier, and antioxidant status. Roach fingerlings (2.26 ± 0.04 g) were fed a basic diet supplemented with three different percentages of G. oblongata powder: 0.25 % (G1), 0.50 % (G2), and 1.0 % (G3) over 8 weeks, with a control group (C) receiving no supplementation. The study found that growth parameters significantly increased in the G1 and G2 groups compared to the C and G3 groups (P < 0.05). Immune responses, measured by total immunoglobulin (Ig) and lysozyme activity, showed a significant increase in the whole-body extract of the G2 group (P < 0.05) and the skin mucus of all treated groups compared to the control (P < 0.05). G. oblongata supplementation did not significantly affect catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities in the whole-body extract, although GPx activity in skin mucus was significantly higher in the supplemented groups. Additionally, the gene expression of interleukin 1-beta (il-1β), occludin, gpx and sod, but not Toll-like receptor increased in G. oblongata treated groups. These results suggest that G. oblongata can serve as a beneficial feed additive in the culture of roach fingerlings, enhancing growth and immune function.

Melatonin inhibits ferroptosis through the ATF3/GPX4 signaling pathway to relieve myocardial ischemia-reperfusion injury in rats.

Melatonin (MEL), functioning as a circulating hormone, is important for the regulation of ferroptosis in different health scenarios and acts as a crucial antioxidant in cardiovascular diseases. However, its specific function in ferroptosis related to myocardial ischemia-reperfusion injury (MIRI) remains to be fully elucidated. In our research, we utilized a rat model of MIRI induced by coronary artery ligation, along with a cell model subjected to hypoxia/reoxygenation (H/R). We evaluated relevant genes and proteins by real-time fluorescent quantitative PCR and Western blot analysis. To evaluate myocardial tissue damage and cell injury, we employed cell counting kit-8 assays, flow cytometry, hematoxylin-eosin staining, and 2,3,5-triphenyltetrazolium chloride staining techniques. Our results show that administering MEL notably reduces the concentrations of cTnT, CK-MB, and lactate dehydrogenase in the serum of MIRI rats, mitigates the extent of myocardial infarction, improves the recovery of pathological conditions in myocardial tissues, and reduces the concentrations of Fe2+, malondialdehyde (MDA), and reactive oxygen species (ROS) in the myocardial tissue, while also promoting increased glutathione levels. Moreover, MEL can also restore the reduced viability of H9C2 cells caused by H/R or ferroptosis inducers (RSL3), reduce the cellular content of Fe2+, MDA, and ROS, and inhibit ferroptosis. Mechanistically, MEL promotes the expression of GPX4 by downregulating the expression of ATF3, thereby inhibiting ferroptosis in cardiomyocytes and ultimately alleviating the process of MIRI. Our study demonstrates that MEL ameliorates MIRI by inhibiting ferroptosis.

The roles of IDH2 and glutathione metabolism in cetuximab resistance in head and neck squamous cell carcinoma investigated by metabolomics and transcriptomics.

Cetuximab resistance is a significant challenge in the treatment of head and neck squamous cell carcinoma (HNSCC). In this study, cetuximab-resistant HNSCC cell lines were established, and untargeted metabolomics was used to detect differences in metabolite profiles between sensitive and resistant cell lines. It was found that glutathione metabolism significantly differed between the sensitive and resistant lines. Combining these findings with transcriptome data, correlation analysis of metabolites revealed that IDH2 regulated glutathione metabolism and contributed to cetuximab resistance in FaDu cells. In vitro experiments showed that IDH2 was highly expressed in FaDu-CR cells, and IDH2 knockdown significantly enhanced the sensitivity of FaDu and FaDu-CR cells to cetuximab. IDH2 knockdown reduced GSH levels and GPX4 expression in FaDu and FaDu-CR cells under cetuximab treatment, while increasing lipid ROS levels. In vivo experiments demonstrated that IDH2 knockdown decreased the tumorigenic ability of FaDu-CR cells in nude mice treated with cetuximab, as well as reduced GPX4 and Ki67 levels in tumor tissues. In conclusion, IDH2 regulated glutathione metabolism and contributed to cetuximab resistance in HNSCC. This study explores strategies to ameliorate cetuximab resistance in HNSCC preclinical models, providing new insights for reversing cetuximab resistance in HNSCC.

N-acetylneuraminic acid promotes ferroptosis of H9C2 cardiomyocytes with hypoxia/reoxygenation injury by inhibiting the Nrf2 axis.

To investigate the mechanism through which N-acetylneuraminic acid (Neu5Ac) exacerbates hypoxia/reoxygenation (H/R) injury in rat cardiomyocytes (H9C2 cells). H9C2 cells were cultured in hypoxia and glucose deprivation for 8 h followed by reoxygenation for different durations to determine the optimal reoxygenation time. Under the optimal H/R protocol, the cells were treated with 0, 5, 10, 20, 30, 40, 50, and 60 mmol/L Neu5Ac during reoxygenation to explore the optimal drug concentration. The cells were then subjected to H/R injury followed by treatment with Neu5Ac, Fer-1 (a ferroptosis inhibitor), or both. The changes in SOD activity, intracellular Fe2+ and lipid ROS levels in the cells were evaluated, and the cellular expressions of Nrf2, GPX4, HO-1, FSP1, and xCT proteins were detected using Western blotting. Following hypoxia and glucose deprivation for 8 h, the cells with reoxygenation for 6 h, as compared with other time lengths of reoxygenation except for 9 h, showed the lowest expression levels of Nrf2, GPX4, HO-1, and FSP1 proteins (P<0.001). Neu5Ac treatment of dose-dependently decreased the viability of the cells with H/R injury with an IC50 of 30.07 mmol/L. Reoxygenation for 3 h with normal glucose supplementation and a Neu5Ac concentration of 30 mmol/L were selected as the optimal conditions in the subsequent experiments. The results showed that Neu5Ac could significantly increase SOD activity, Fe2+ and lipid ROS levels and reduce Nrf2, GPX4, HO-1, and FSP1 protein expressions in H9C2 cells with H/R injury, but its effects were significantly attenuated by treatment with Fer-1. Neu5Ac exacerbates ferroptosis of myocardial cells with H/R injury by inhibiting the Nrf2 axis to promote the production of ROS and lipid ROS.

Cotargeting of thioredoxin 1 and glutamate-cysteine ligase in both imatinib-sensitive and imatinib-resistant CML cells.

Chronic myeloid leukemia (CML) is a type of malignancy characterized by harboring the oncogene Bcr-Abl, which encodes the constitutively activated tyrosine kinase BCR-ABL. Although tyrosine kinase inhibitors targeting BCR-ABL have revolutionized CML therapy, native and acquired drug resistance commonly remains a great challenge. Thioredoxin 1 (Trx1) and glutamate-cysteine ligase (GCL), which are two major antioxidants that maintain cellular redox homeostasis, are potential targets for cancer therapy and overcoming drug resistance. However, how their inhibition is implicated in CML is still unclear. Here, our results revealed that Trx1 was overexpressed in patients with CML compared with healthy donors. Trx1 expression was greater in imatinib-resistant CML cells than in imatinib-sensitive cells. Pharmacological inhibitors of Trx1 attenuated cell growth and reduced colony formation in both imatinib-sensitive and imatinib-resistant CML cells. Furthermore, decreased Trx1 expression enhanced the cytotoxicity of the GCL inhibitor buthionine sulfoximine (BSO). We surmise that the combined inhibition of Trx1 and GCL promotes the induction of hydrogen peroxide and depletes GPX4 expression in CML cells, resulting in ferroptosis in cancerous cells. Finally, the combined inhibition of Trx1 and GCL had a synergistic effect on CML cells in murine xenograft models. These findings offer crucial informationregarding the combined roles ofTrx1 and GCL in triggering ferroptosis in CML and suggestefficacioustherapeutic uses for these systems in this disease.

Integrating network pharmacology and experimental verification to reveal the ferroptosis-associated mechanism of Changpu-Yizhi-Wan in the treatment of Alzheimer's disease.

To explore the pharmacological mechanism of Changpu-Yizhi-Wan (CYW) in the treatment of Alzheimer's disease (AD) from the perspective of ferroptosis based on network pharmacology and experimental verification. The Encyclopedia of Traditional Chinese Medicine 2.0 (ETCM2.0) database was used to collect the active components of CYW, and the putative targets were predicted in ETCM2.0 and SwissTargetPrediction database. The AD related targets were collected from GeneCards, comparative toxicogenomics database (CTD), Online Mendelian Inheritance in Man (OMIM), DisGeNET and Therapeutic Target Database (TTD), the ferroptosis related targets were collected from FerrDb V2 database, and the common targets of CYW, AD and ferroptosis were calculated by Venny2.1 platform. Protein-protein interaction (PPI) analysis was performed by STRING database, and the active compounds-target network and the PPI network were constructed using Cytoscape software. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Reactome pathway enrichment analysis were performed through DAVID database. RSL3 was used to induce HT22 cells to establish a neuronal ferroptosis cell model, and the inhibitory effect of CYW on neuronal ferroptosis was evaluated by cell viability assay, intracellular iron assay and lipid peroxidation staining. The ferroptosis-associated key protein expressions of Nrf2, SLC7A11, GPX4 and FTH1 were detected by Western blot. A total of 100 candidate compounds were identified from CYW, and 1129 putative targets were obtained. 3924 AD-related targets and 564 ferroptosis-related targets were collected, respectively. There were 78 common targets between them and CYW targets, which were potential targets for CYW to regulate ferroptosis in the treatment of AD. PPI network analysis identified 10 key targets, including TP53, IL6, STAT3, HIF1A, NFE2L2, and others. GO, KEGG and Reactome enrichment analysis showed that 78 potential targets were involved in the regulation of ferroptosis and Nrf2-mediated gene transcription. Molecular docking showed that some active components of CYW had good affinity with Nrf2. In RSL3-induced HT22 cells, CYW significantly improved cell viability, reduced intracellular iron levels and inhibited lipid peroxidation, and improved the protein expression of Nrf2, SLC7A11, GPX4 and FTH1. The pharmacological mechanism of CYW in the treatment of AD may be related to the regulation of Nrf2/SLC7A11/GPX4/FTH1 axis to inhibit neuronal ferroptosis.

Relative bioavailability of selenium yeast, selenomethionine, hydroxyl-selenomethionine and nano-selenium for broilers.

Selenium (Se) is an essential trace element for humans and animals. Development and application of new forms of Se sources with lower toxicity and higher bioavailability has been attracting more attention. However, the bioavailabilities of Se from several new Se sources for broilers remain unclear. Therefore, the aim of this study was to assess the relative bioavailabilities of Se from Se yeast (SY), selenomethionine (SM), hydroxyl-selenomethionine (SO) and nano-Se (NS) relative to sodium selenite (SS) for broilers fed a conventional corn-soybean meal diet. A total of 576 one-day-old Arbor Acres commercial male broilers were randomly assigned to 16 treatments with 6 replicate cages per treatment in a completely randomized design involving a 5 (Se sources: SY, SM, SO, NS and SS) × 3 (added Se levels: 0.15, 0.30 and 0.45 mg Se/kg) factorial design of treatments plus 1 (a Se-unsupplemented control) for 21 d. The relative bioavailabilities of Se sources were estimated based on plasma or tissue Se concentrations as well as selenoprotein mRNA expressions and activities in broilers. The results showed that the Se concentrations and glutathione peroxidase (GPX) activities in plasma, liver, breast muscle, pancreas and kidney as well as Se concentration in erythrocytes of broilers, and Gpx1 and Selenop mRNA expressions in pancreas increased linearly (p < 0.03) as added Se level increased. Furthermore, the differences (p < 0.05) among different Se sources were detected for the Se concentrations in liver, breast muscle, pancreas and erythrocytes, GPX activities in pancreas and kidney. Based on slope ratios from the multiple linear regressions of the above indices, the Se bioavailabilities of SY, SM, SO, NS relative to SS (100%) were 78 to 367%, 67.8 to 471%, 57 to 372%, and 45 to 92%, respectively. The results from this study indicated that the Se from SM, SY and SO are more available to broilers than the Se from SS in enhancing the Se concentrations in liver, breast muscle, pancreas and erythrocytes and GPX activity in pancreas, and the Se from SM had the highest while the Se from NS had the lowest relative bioavailability.

Oxyresveratrol as a novel ferroptosis inducer exhibits anticancer activity against breast cancer via the EGFR/PI3K/AKT/GPX4 signalling axis.

Oxyresveratrol (ORes) exhibits significant anticancer activity, particularly against breast cancer. However, its exact mechanism of action (MOA) remains unclear. This study aimed to investigate the pharmacological activity and underlying MOA. The inhibitory effect of ORes on breast cancer cell growth was confirmed, and the effective concentrations were determined for further experiments. Gene expression profiles (GEPs) were collected from MDA-MB-231 cells treated with ORes at varying concentrations using HTS2. Bioinformatics tools were used to predict the anticancer activity and MOA of ORes. Ferroptosis markers (ferrous ions, reactive oxygen species, lipid peroxidation, and GPX4 expression) were assessed, and mitochondrial morphology was observed. The effect of ORes on tumour growth was evaluated in vivo, along with the analysis of ferroptosis in tissues. The MOA was explored using L1000, Drug Gene DataBase (DGDB), and Western blotting analyses. ORes significantly reduces breast cancer cell viability and proliferation in a concentration-dependent manner, with IC50 values of 104.8μM, 150.2μM, and 143.6μM in MDA-MB-231, BT-549, and 4T1 cells, respectively. GEPs induced by ORes were significantly enriched in the ferroptosis and PI3K/AKT signalling pathways. ORes inhibited breast cancer cell growth, increased intracellular ferrous ion levels, reactive oxygen species, and lipid peroxidation, and induced ferroptosis-related mitochondrial alterations. These effects were associated with decreased GPX4 expression and suppression of EGFR, phosphorylated PI3K, and phosphorylated AKT. ORes inhibited tumour growth, enhanced iron deposition, and reduced GPX4 expression in tumour tissues in vivo. Notably, treatment with the ferroptosis inhibitor ferrostatin-1 (Ferr-1) attenuated the anticancer effects of ORes, confirming the pivotal role of ferroptosis in ORes-mediated breast cancer inhibition. ORes inhibits breast cancer cell growth by inducing ferroptosis through suppression of the EGFR/PI3K/AKT/GPX4 signalling axis. This study suggests that ORes holds promise as a potential therapeutic agent for breast cancer and warrants further investigation into its clinical applications and potential integration into existing treatment regimens.

MiRNA-541-5p regulates myocardial ischemia–reperfusion injury by targeting ferroptosis

BackgroundThis article aims to use high-throughput sequencing to identify miRNAs associated with ferroptosis in myocardial ischemia–reperfusion injury, select a target miRNA, and investigate its role in H9C2 cells hypoxia-reoxygenation injury.MethodsSD rats and H9C2 cells were used as subjects. ELISA kits quantified MDA, SOD, GSH, LDH, and ferritin levels. TTC staining evaluated infarction size. HE staining observed histopathological changes. DCFH-DA fluorescent probe detected ROS. CCK-8 kit measured cell viability. HiSeq 2000 sequencing performed differential expression analysis of miRNAs. qRT-PCR and Western blots assessed the expression levels of GPX-4, ACSL-4, HO-1, TFR-1 and TFR-2. SPSS 21.0 software conducted statistical analysis.ResultsMyocardial ischemia–reperfusion injury resulted in decreased levels of SOD and GSH, increased levels of LDH and MDA, up-regulation of ferritin, ACSL-4, HO-1, and TFR-2, down-regulation of GPX-4, increased tissue damage, and accumulation of ROS. However, DFO treatment reversed these changes. Subsequently, the target gene miRNA-541-5p was obtained by miRNA sequencing screening, and further validation revealed that miRNA-541-5p expression was increased in the myocardial tissues of rats in the I/R injury model group compared with those of rats in the NC group, P < 0.05. Subsequently, by constructing H9C2 cell lines with miRNA-541-5p overexpression and miRNA-541-5p expression inhibition, miRNA-541-5p expression was inversely correlated with the survival of H9C2 cells after hypoxia-reoxygenation injury. miRNA-541-5p up-regulation led to a decrease in SOD and GSH, an increase in ferritin and MDA, and an accumulation of ROS. wb and qRT-PCT demonstrated that high miRNA-541-5p expression up-regulated the expression of protein/mRNA expression of ACSL-4, HO-1, ferritin, and TFR-1, but down-regulated protein/mRNA expression of GPX-4. In addition, ADAM 7, FNIP 2, HOXD 10, HCCS and STK 3 were preliminarily identified as potential candidate target genes for miRNA-541-5p by bioinformatics analysis. Among them, ADAM7 emerges as the most suitable potential target gene based on the selection criteria.ConclusionIn summary, miRNA-541-5p may be a biomarker of myocardial I/R damage diseases and can regulate oxidative stress and iron death by inhibiting the expression of miRNA-541-5p, thereby reducing mechanisms of I/R injury.

Effects of Feed Supplementation With Fulvic Acid on the Systemic and Mucosal Protective Mechanisms of Juvenile Rainbow Trout (Oncorhynchus mykiss).

Rainbow trout (Oncorhynchus mykiss) is an important fish species raised in aquaculture, but it is susceptible to stress, infections diseases. The present study aimed to determine the effects of fulvic acid feed addition on the systemic and mucosal protective mechanisms of juvenile rainbow trout and to elucidate the underlying molecular mechanisms of changes in the gut. Rainbow trout (4.30 ± 0.6 g) diet was supplemented with different levels of fulvic acid: 0% (Control), 0.5%, 1% and 2%. At the end of 8-week feeding trial, growth parameters such as final weight gained weight (%), SGR (F1%) increased, and FCR (all levels) decreased significantly compared to the control group. We found that the activity of lysozyme, glutathione peroxidase, and catalase in the serum were significantly improved, especially after the addition of 0.5% and 1% of fulvic acid. At the same time, the immunoglobulin concentration in the skin mucus was increased with 0.5% supplementation. However, the expression of tnf-α, il-6 and gpx in the intestine was strongly upregulated after supplementation with 2%, indicating oxidative stress and inflammation with this level of fulvic acid inclusion. Furthermore, the mucus lysozyme activity was reduced at this concentration, which can increase the susceptibility to pathogen invasion. The results suggest that adding 0.5%-1% of fulvic acid to the feed of juvenile rainbow trout can help to improve their immune and antioxidative defenses and thereby support the wellbeing of fish.

Ghrelin Induces Ferroptosis Resistance and M2 Polarization of Microglia to Alleviate Neuroinflammation and Cognitive Impairment in Alzheimer's Disease.

Microglial polarization and ferroptosis are important pathological features in Alzheimer's disease (AD). Ghrelin, a brain-gut hormone, has potential neuroprotective effects in AD. This study aimed to explore the potential mechanisms by which ghrelin regulates the progression of AD, as well as the crosstalk between microglial polarization and ferroptosis.Mouse BV2 microglial cells and male mice were treated with beta-amyloid (Aβ) (1-42) to simulate the AD environment. Microglia ferroptosis was measured by detecting levels of ferroptosis-related proteins (SLC7A11, GPX4, FTL1, and FTH1), metabolic markers (ROS, MDA, GSH, SOD), and observing mitochondrial morphological changes. Microglial polarization was evaluated by measuring levels of inflammatory markers and surface markers. The impact of ghrelin on Aβ1-42-exposed microglia was assessed by coupling with the ferroptosis activator Erastin. Cognitive impairment in AD mice was evaluated through behavioral tests. Tissue staining was applied to determine neuronal damage.In Aβ1-42-exposed microglia, ghrelin upregulated the protein expression of SLC7A11, GPX4, FTL1 and FTH1, reduced ROS and MDA levels, and elevated GSH and SOD levels through the BMP6/SMAD1 pathway. Ghrelin alleviated mitochondrial structural damage. Additionally, ghrelin reduced levels of pro-inflammatory factors and CD86, while increasing levels of anti-inflammatory factors and CD206. Erastin reversed the effects of ghrelin on ferroptosis and phenotypic polarization in Aβ1-42-exposed microglia. In AD mice, ghrelin ameliorated abnormal behavior, neuroinflammation, and plaque deposition. Ghrelin attenuated iNOS/IBA1-positive expression and enhanced Arg-1/IBA1-positive expression in the hippocampus. Ghrelin induces microglial M2 polarization by inhibiting microglia ferroptosis, thereby alleviating neuroinflammation. Our results indicate that ghrelin may serve as a promising potential agent for treating cognitive impairment in AD.

Silencing of FZD7 Inhibits Endometriotic Cell Viability, Migration, and Angiogenesis by Promoting Ferroptosis.

Endometriosis (EMS) is a difficult gynecological disease to cure. Frizzled-7 (FZD7) has been shown to be associated with the development of EMS, but its specific mechanism remains unclarified. This study aims to explore the role of FZD7 in EMS. RT-qPCR and western blot were used to detect the expression level of FZD7 in human endometrial stromal cells (hESCs) and human ectopic endometrial stromal cell line hEM15A. The interfering plasmid of FZD7 was established. CCK-8, EdU, wound healing, transwell invasion, and cytoskeletal staining assays were applied to evaluate the role of FZD7 silencing in hEM15A cell proliferation, invasion, and migration. Tube forming ability of cells was evaluated by tube formation assay. Cellular VEGF, GSH, and MDA levels were measure by kits. Intracellular lipid ROS and Fe2+ levels were tested using C11-BODIPY (581/591) and FeRhoNox-1 probes, respectively. The ferroptosis-related protein SLC7A11, GPX4, and ACSL4 expressions were analyzed using western blot. The effects of ferroptosis on endometriotic cell viability, migration, and angiogenesis were further analyzed with the addition of an ferroptosis inhibitor (Fer-1). FZD7 was upregulated in hEM15A cells, and silencing of FZD7 inhibited cell proliferation, migration, invasion, and angiogenesis abilities. Downregulation of FZD7 decreased cellular GSH level and elevated MDA level. Knockdown of FZD7 also caused an increase in intracellular ROS and Fe2+ levels, as well as the downregulation of SLC7A11 and GPX4 levels and the upregulation of ACSL4 level, which are hallmarks of ferroptosis. However, the inhibitory effects of FZD7 knockdown on hEM15A cell progression were reversed when ferroptosis inhibitor Fer-1 added. The above indices suggest that FZD7 knockdown regulates endometriotic cell proliferation, invasion, migration, and angiogenesis via ferroptosis.