Expression Of Glutathione Peroxidase Research Articles

Condensed tannin from Caragana korshinskii extraction and protection effects on intestinal barrier function in mice

Caragana korshinskii tannins (CKT) were extracted by response surface methodology and the protection effect of CKT on the jejunal mucosal barrier function of mice was investigated. Firstly, this work presents the extraction, purification and characterization of CKT. The results show that the extraction conditions were as follows: extraction temperature was 52°C, extraction time was 95 min, liquid-solid ratio was 20:1 and acetone volume fraction was 62%. The extraction yield of the CKT was 5.34%. The CKT has a typical polyphenol peak with a molecular weight of 8.662 kDa and is composed of epigallocatechin, catechin, epigallocatechin gallate, epicatechin, gallocatechin, epicatechin-3-o-gallate and catechin gallate with a molar ratio of 1:8.88:2.65:1.55:1.92:0.49:0.14. Additionally, the CKT showed strong antioxidants capacity in vitro. Secondly, the protection effect of CKT on the growth performance and mucosal barrier function of the mouse jejunum was examined. Totally, sixty KM mice were randomly divided into six treatment groups (n = 10) using a single-factor completely randomized experimental design. The treatment groups were intragastrically administered with 0, 25, 50, 100, 200, and 400 mg/kg BW of CKT aqueous solution once a day. The gavage volume was set at 0.2 mL per 10 g of body weight, administered daily for 21 days. The results showed that CKT significantly improved growth performance and physiological state of mouse intestine. CKT strengthened the intestinal physical barrier by upregulating the expression of Occludin and ZO-1 and decreasing the levels of serum diamine oxidase (DAO) and D-lactate (D-LA). Regarding biochemical barrier, CKT could upregulate the activity and gene expression of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and decreasing the content of malondialdehyde (MDA) in jejunum tissues. Generally, CKT may be used as a functional feed additive to regulate intestinal mucosal function, thereby enhancing the health of the intestine and host.

The effects of ursodeoxycholic acid on Parkinson's disease, a mechanistic review of the recent evidence.

Parkinson`s disease stands as the second-most widespread neurodegenerative disorder. Parkinson`s disease is relentless in progression and irreversible in nature, for which there is no cure. Therapies are only used to attenuate motor symptoms. As Parkinson`s disease is primarily defined by degeneration of dopaminergic neurons in the substantia nigra, and considering that neuroinflammation and mitochondrial dysfunction in these neurons are key factors contributing to disease progression, alternative therapies should aim to preserve healthy mitochondria.Method.Eligible studies on the effect of Ursodeoxycholic acid (UDCA) on Parkinson`s disease were collected from PubMed, Google Scholar, Scopus, Web of Science and Cochrane library for clinical, in-vivo, and in-vitro studies.Result.UDCA and its taurine conjugate (TUDCA), which are endogenous bile acids, have exhibited neuroprotective potential in various neurological conditions, such as Alzheimer's disease, Parkinson's disease and Huntington's disease, in both animal experimental models and clinical investigations. This is attributed to three significant properties, in addition to their capability to cross the blood-brain barrier. First, their anti-inflammatory properties are manifested through the reduction of significant inflammatory factors such as tumor necrosis factor-α, interleukin 1β and other related elements. Second, their antioxidant property is marked by an increase in the expression of superoxide dismuthase, glutathione peroxidase and other antioxidant enzymes. The third property is the antiapoptotic activity, characterized by decreased caspase-3 activity and lower expression of pro-apoptotic Bax in the striatum.Conclusion.Based on this comprehensive review, UDCA and TUDCA have the potential to be considered as a therapeutic agent in the management of the Parkinson's disease.

Hypericin mediated photodynamic therapy induces ferroptosis via inhibiting the AKT/mTORC1/GPX4 axis in cholangiocarcinoma.

Cholangiocarcinoma remains a challenging primary hepatobiliary malignancy with dismal prognosis. Photodynamic therapy (PDT),a less invasive treatment, has been found to inhibit the proliferation and induce ferroptosis, apoptosis and necrosis in other tumor cells in recent years. Regrettably, the role and exact molecule mechanism of PDT is still incompletely clear in cholangiocarcinoma cells. Ferroptosis is a novel regulated cell death(RCD), which is controlled by glutathione peroxidase4(GPX4) with the characteristics of iron dependent and excessive intracellular accumulation of lipid peroxides. This novel form of RCD has attracted great attention as a potential new target in clinical oncology during recent years. In this study, we observed that hypericin mediated PDT(HY-PDT) could significantly inhibit the proliferation of the cholangiocarcinoma cells and suppress migration and the epithelial mesenchymal transition (EMT) as well. Then, we conducted transcriptome sequencing and bioinformatics analysis and observed that HY-PDT was most likely involved in ferroptosis, apoptosis, the EMT process and AKT/mTORC1 signaling pathways in cholangiocarcinoma cells. Next, a series of in vitro and in vivo experiments were performed to confirm that HY-PDT could trigger cholangiocarcinoma cells ferroptosis through inhibiting the expression of GPX4 protein. In terms of molecular mechanism, we found that HY-PDT induced ferroptosis by decreasing GPX4 expression via suppression of the AKT/mTORC1 signaling pathway. In addition, we also found that HY-PDT inhibit cholangiocarcinoma cells migration and the EMT process by inhibiting the AKT/mTORC1 pathway. Our study illustrated a new mechanism of action for HY-PDT and might throw light on the individualized precision therapy for cholangiocarcinoma patients.

Seeding Janus Zn-Fe Diatomic Pairs on a Hollow Nanobox for Potent Catalytic Therapy.

Dual atomic nanozymes (DAzymes) are promising for applications in the field of tumor catalytic therapy. Here, integrating with ultrasmall Fe5C2 nanoclusters, asymmetric coordination featuring Janus Zn-Fe dual-atom sites with an O2N2-Fe-Zn-N4 moiety embedded in a carbon vacancy-engineered hollow nanobox (Janus ZnFe DAs-Fe5C2) was elaborately developed. Theoretical calculation revealed that the synergistic effects of Zn centers acting as both adsorption and active sites, oxygen-heteroatom doping, carbon vacancy, and Fe5C2 nanoclusters jointly downshifted the d-band center of Fe 3d orbitals, optimizing the desorption behaviors of intermediates *OH, thereby significantly promoting catalytic activity. Upon 1064 nm laser irradiation, Janus ZnFe DAs-Fe5C2 with superior photothermal conversion efficiency (η = 62.5%) showed thermal-augmented catalytic therapy. Fascinatingly, Janus ZnFe DAs-Fe5C2 with multienzymatic properties can suppress the expression of glutathione peroxidase 4 and accelerate the accumulation of lipid peroxides, through which ferroptosis is triggered. Overall, tannin-involved asymmetric Janus ZnFe DAs-Fe5C2 will inspire more inventions of biodegradable DAzymes for tumor therapy application.

Placental Hypoxia-Induced Ferroptosis Drives Vascular Damage in Preeclampsia.

Iron is an essential micronutrient for cell survival and growth; however, excess of this metal drives ferroptosis. Although maternal iron imbalance and placental hypoxia are independent contributors to the pathogenesis of preeclampsia, a hypertensive disorder of pregnancy, the mechanisms by which their interaction impinge on maternal and placental health remain elusive. We used placentae from normotensive and preeclampsia pregnancy cohorts, human H9 embryonic stem cells differentiated into cytotrophoblast-like cells, and placenta-specific Phd2-/- preeclamptic mice. Lipid peroxidation and iron cargo of placenta-derived small extracellular vesicles (sEVs) isolated from the maternal circulation of control and preeclampsia individuals were examined by mass spectrometry, flow cytometry, and colorimetry. Human microvascular endothelial cells' angiogenic capacity and function were examined after exposure to control and pathological sEVs. Placentae from preeclampsia pregnancies contain increased ferrous iron and lipid peroxidation byproduct, malondialdehyde. Antioxidant capacity is significantly lower in preeclampsia placentae, with decreased glutathione content, and GPx4 (glutathione peroxidase 4) expression and activity. Hypoxia triggers the occurrence of ferroptosis in human trophoblast cells and mouse Phd2-/-placentae. Disrupted placental iron homeostasis in preeclampsia is accompanied by improper extrusion of iron through sEVs mediated by the pentaspan protein prominin-2. Heightened lipid peroxidation content was found in villous explants and maternal circulating sEVs of preeclampsia individuals. Exposure of human microvascular endothelial cells to preeclampsia-derived placental sEVs results in endothelial activation and impaired angiogenesis, which is rescued by treatment with hinokitiol, a compound known to restore tissue iron balance. In pregnancy, iron and oxygen work synergistically to conserve an operative antioxidant system to maintain iron homeostasis and protect the placenta from ferroptotic death. Hindrance to this system due to hypoxia results in heightened ferroptosis rates and sEV-mediated extrusion of harmful lipid peroxides from trophoblast cells into the circulation thereby contributing to maternal endothelial dysfunction characterizing preeclampsia.

Correlation between selenium levels and selenoproteins expression in idiopathic generalized epilepsy: a study from Karachi

BackgroundOxidative damage has been implicated in multiple neurodegenerative diseases, including epilepsy. Selenium, in the form of selenoproteins is an integral part of the human antioxidant defense system. Though a relationship between the altered selenium levels and epilepsy has been reported, limited evidence is available about the expression pattern of selenoproteins in epileptic patients.ObjectiveThis study aimed to determine the serum selenium levels in idiopathic epileptic and healthy individuals. Expression profiling of selenoproteins (GPx1, TRxR1 and SEPW1) both at mRNA and protein levels was also evaluated.MethodsSerum selenium levels of 30 patients with idiopathic generalized epilepsy and their age and gender matched 30 healthy controls were measured. Protein levels of Serum Glutathione Peroxidase 1 (GPx1), Thioredoxin Reductase 1 (TRxR1) and Selenoprotein W (SEPW1) were estimated using ELISA. mRNA expression of GPx1, TRxR1 and SEPW1 were determined using qRT-PCR.ResultsThe mean values for serum selenium levels in cases and controls were 37.6 ± 2.0 µmol/ml and 38.9 ± 2.7 µmol/ml, respectively. Selenium levels in cases were significantly lower as compared to controls (p = 0.031). No statistically significant differences were observed between the serum levels of selenoproteins GPx1, TRxR1 and SEPW1 in epileptic patients and the healthy group. GPx1 and TRxR1 expression was found to be down regulated (0.34 and 0.13 folds respectively) whereas SEPW 1 was found to be 0.04 folds up regulated in epileptic patients compared to the healthy subjects.ConclusionSelenium deficiency observed in epileptic patients suggests the association between serum selenium levels and epilepsy. This study provides the information about the selenium status in Pakistani population and helps in understanding the role of selenium in the prevention of epilepsy.Graphical

Investigation of the Mechanism of Pachyman against Gout Arthritis with Network Pharmacology Analysis and Verification In Vivo.

Pachyman, derived from Poria cocos, has been used to treat gouty arthritis (GA) for thousands of years, although its precise role and mechanisms remain unclear. Herein, we investigate the therapeutic effects of pachyman on GA and explore their underlying mechanisms. Network pharmacology and experimental methods were employed to investigate the therapeutic mechanisms of pachyman against GA. The protein-protein interaction network of shared targets between pachyman and gout was constructed. Furthermore, we elucidated the functions and mechanisms of pachyman against GA. Subsequently, we validated the predicted mechanisms from an experiment on rats. The treatment of GA with pachyman primarily related to tumor necrosis factor (TNF), matrix metalloproteinases (MMP), and relaxation factor signaling pathways. In the experimental validation, pachyman were found to regulate the expression of IL-1β, TNF-α, TGF-β, superoxide dismutase, and glutathione peroxidase of hyperuricemic rats. These collective findings suggest that pachyman holds promise as an alternative treatment for GA.

Regulation of enzymatic lipid peroxidation in osteoblasts protects against postmenopausal osteoporosis

Oxidative stress plays a critical role in postmenopausal osteoporosis, yet its impact on osteoblasts remains underexplored, limiting therapeutic advances. Our study identifies phospholipid peroxidation in osteoblasts as a key feature of postmenopausal osteoporosis. Estrogen regulates the transcription of glutathione peroxidase 4 (GPX4), an enzyme crucial for reducing phospholipid peroxides in osteoblasts. The deficiency of estrogen reduces GPX4 expression and increases phospholipid peroxidation in osteoblasts. Inhibition or knockout of GPX4 impairs osteoblastogenesis, while the elimination of phospholipid peroxides rescues bone formation and mitigates osteoporosis. Mechanistically, 4-hydroxynonenal, an end-product of phospholipid peroxidation, binds to integrin-linked kinase and triggers its protein degradation, disrupting RUNX2 signaling and inhibiting osteoblastogenesis. Importantly, we identified two natural allosteric activators of GPX4, 6- and 8-Gingerols, which promote osteoblastogenesis and demonstrate anti-osteoporotic effects. Our findings highlight the detrimental role of phospholipid peroxidation in osteoblastogenesis and underscore GPX4 as a promising therapeutic target for osteoporosis treatment.

The Inhibitory Effects of NCT503 and Exogenous Serine on High-Selenium Induced Insulin Resistance in Mice.

This study aims to identify whether the development of insulin resistance (IR) induced by high selenium (Se) is related to serine deficiency via the inhibition of the de novo serine synthesis pathway (SSP) by the administrations of 3-phosphoglycerate dehydrogenase (PHGDH) inhibitor (NCT503) or exogenous serine in mice. forty-eight male C57BL/6J mice were randomly divided into four groups: adequate-Se (0.1 mgSe/kg), high-Se (0.8 mgSe/kg), high-Se +serine (240 mg/kg/day), and high-Se +NCT503 (30 mg/kg, twice a week) for 5 months. The glucose tolerance test (GTT) and insulin tolerance test (ITT) were used to confirm the development of IR in mice with high-Se intake, and fasting blood glucose levels were measured monthly. The Se contents in plasma and tissues were detected by ICP-MS. The levels of insulin (INS), homocysteine (HCY), and serine in plasma were tested by ELISA. Western blot analyses were conducted to evaluate the protein expressions of glutathione peroxidase 1 (GPX1), selenoprotein P (SELENOP) and PHGDH, the PI3K-AKT-mTOR pathway, folate cycle (SHMT1, MTHFR), and methionine cycle (MS). An IR model was developed in mice from the high-Se group with elevated fasting blood glucose and INS levels, impaired glucose tolerance, and reduced insulin sensitivity, but not in both the high-Se +serine group and the high-Se +NCT503 group. Compared with the high-Se and high-Se +serine groups, the expressions of GPX1 and SELENOP significantly decreased for the high-Se +NCT503 group in the liver, muscle, and pancreas tissues. The expression of PHGDH of high-Se group was significantly higher than that of the adequate-Se group in the liver (p < 0.05) and pancreas (p < 0.001). Also, the expected high expression of PHGDH was effectively inhibited in mice from the high-Se +serine group but not from the high-Se +NCT503 group. The expression of p-AKT (Ser-473) for the high-Se group was significantly lower than that of the adequate-Se group in the liver, muscle, and pancreas. The IR induced by high-Se intake in the body has been confirmed to be partially due to serine deficiency, which led to the initiation of SSP to produce endogenous serine. The supplementations of exogenous serine or inhibitors of PHGDH in this metabolic pathway could be used for the intervention.

The prognostic importance of the negative regulators of ferroptosis, GPX4 and HSPB1, in patients with colorectal cancer.

The prognostic value of negative regulators of ferroptosis in patients with colorectal cancer (CRC) has not yet been fully elucidated. The present study performed a systematic in silico identification and selection of candidate negative regulators of ferroptosis using The Cancer Genome Atlas data cohort (n=367), followed by clinical validation through immunohistochemistry of samples from patients with CRC (n=166) and further in vitro evaluation. In silico analysis identified specific light-chain subunit of the cystine/glutamate antiporter, AIFM2, NFE2L2, FTH1, GLS2, glutathione peroxidase 4 (GPX4) and heat shock protein β-1 (HSPB1) genes as possible candidates. Furthermore, patients with high expression of GPX4 or HSPB1 exhibited significantly worse overall survival (OS) compared with those with low expression (P<0.01 for both). Immunohistochemical analysis revealed that both OS and recurrence-free survival (RFS) of patients with CRC and high GPX4 or HSPB1 expression were significantly worse compared with in patients with low expression (P<0.01 for all). Furthermore, multivariate analysis showed that high GPX4 and HSPB1 expression were independent risk factors for poor oncological outcome for OS and RFS (GPX4: RFS, P=0.03; HSPB1: OS, P=0.006 and RFS, P<0.0001). Moreover, the effects of GPX4 and HSPB1 small interfering RNAs on two CRC cell lines (DLD-1 and SW480) indicated that GPX4 and HSPB1 may exhibit important roles in attenuating the cytotoxic effect of 5-fluorouracil-based chemotherapy. In conclusion, the current study confirmed that GPX4 and HSPB1 may serve as substantial prognostic- and recurrence-predictive biomarkers in patients with CRC.

N-acetyl-L-cysteine and lauric acid; effective antioxidant and antimicrobial feed additives for juvenile Pacific white shrimp (Litopenaeus vannamei) cultured at high stocking density.

Present study aimed at improving the immune and antioxidant response of Pacific white shrimp (Litopenaeus vannamei) cultured at high stocking density fed with 0.2% supplementation of lauric acid (LA) and N-acetyl-L-cysteine (NAC). Shrimp (initial average weight = 0.65 g; n = 270) were grown at low stocking density (LSD) (n = 10/0.80 ft3 per replicate) and high stocking density (HSD) (n = 20/0.80 ft3 per replicate). They were randomly distributed into five groups (T1: negative control at LSD, T2: positive control at HSD, T3: at HSD and fed with LA supplement diet, T4: at HSD and fed with NAC supplemented diet, T5: at HSD and fed with combination of LA and NAC). All these five treatments were studied in triplicates and study continued for eight weeks. Better growth and higher levels of glucose, total protein, total hemocyte count and phagocytic index were observed in shrimp fed with NAC and LA supplemented diets. Observed survival rate and feed conversion ratio in all treatments was 75-89% and < 0.82, respectively. All parameters indicating stress were observed to be higher in T1 as compared to T2. Improved expression of superoxide dismutase and glutathione peroxidase and lower levels of malondialdehyde genes in T3, T4 and T5 showed that supplementation with these nutraceuticals can improve antioxidant response at high stocking density. A parallel increase was observed in the profiles of prophenoloxidase and lysozyme, underscoring the immune-boosting effects of both NAC and LA. This finding was further supported by higher expression of innate immune signaling pathway-related gene, toll like receptor-2 in T3, T4 and T5. In conclusion, NAC and LA, can possibly improve the resistance of white pacific shrimp against oxidative stress and pathogens when cultured in intensive production system.

Activation of the De Novo Serine Synthesis Pathway and Disruption of Insulin Signaling Induced by Supplemental SeMet in Vitro.

Selenium (Se) intake or selenoprotein overexpression can cause abnormal glucose metabolism and increase the risk of type 2 diabetes (T2D). The purpose of this study is to observe whether glycolysis bypass in the de novo serine synthesis pathway (SSP) is activated under high-Se stress in vitro. Initially, HCT-116, L02, HepG2, and differentiated C2C12 cells were exposed to five selenomethionine (SeMet) concentrations (0.001 to 10µmol/L) for 48h. The expressions of glutathione peroxidase 1 (GPX1), selenoprotein P (SELENOP), 3-phosphoglycerate dehydrogenase (PHGDH), and serine hydroxy-methyltransferases 1 (SHMT1) were assessed by western blotting (WB). Then, corresponding to the peak expressions of GPX1, SELENOP, and PHGDH, 0.1µmol/L SeMet was identified as the highest intervention concentration. With more detailed levels of SeMet (0.001 to 0.1µmol/L) given, the differentiated C2C12 cells were treated for 48h to analyze the expressions of selenoproteins, enzymes related with serine metabolism and insulin signaling pathway. Among the four cell lines, the expressions of selenoproteins and metabolic enzymes of serine in C2C12 cells were more sensitive to changes in Se concentrations, which was similar to that in L02 cells. In C2C12 cells, the expressions of GPX1, SELENOP, selenoprotein N (SELENON), PHGDH, and SHMT1 exhibited a parabolic inflection point at SeMet concentrations of 0.05µmol/L or 0.075µmol/L, while 5,10-methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MS) showed no such trend. After 15min of insulin stimulation, glucose retained more in the culture medium due to the decreased uptake by C2C12 cells. The expressions of key enzymes (AKT, AKT (Ser-473), AKT (Thr-308), mTOR, and PI3K) in the PI3K-AKT-mTOR signaling pathway decreased with the increased level of SeMet. This study demonstrated that excessive Se intake could induce abnormal glucose metabolism via SSP and impair the normal signaling of insulin in the differentiated C2C12 cells.

An eCIRP inhibitor attenuates fibrosis and ferroptosis in ischemia and reperfusion induced chronic kidney disease

BackgroundChronic kidney disease (CKD) is a leading cause of death in the United States, and renal fibrosis represents a pathologic hallmark of CKD. Extracellular cold-inducible RNA-binding protein (eCIRP) is a stress response protein involved in acute inflammation, tissue injury and regulated cell death. However, the role of eCIRP in chronic inflammation and tissue injury has not been elucidated. We hypothesize that eCIRP is involved in renal ischemia/reperfusion (RIR)-induced CKD and that C23, an antagonist to eCIRP, is beneficial in attenuating renal fibrosis and ferroptosis in RIR-induced CKD.MethodsC57BL/6 (WT) or CIRP−/− mice underwent renal injury with total blockage of blood perfusion by clamping bilateral renal pedicles for 28 min. In the WT mice at the time of reperfusion, they were treated with C23 (8 mg/kg) or vehicle. Blood and kidneys were harvested for further analysis at 21 days thereafter. In a separate cohort, mice underwent bilateral RIR and treatment with C23 or vehicle and were then subjected to left nephrectomy 72 h thereafter. Mice were then monitored for additional 19 days, and glomerular filtration rate (GFR) was assessed using a noninvasive transcutaneous method.ResultsIn the RIR-induced CKD, CIRP−/− mice showed decreased collagen deposition, fibronectin staining, and renal injury as compared to the WT mice. Administration of C23 ameliorated renal fibrosis by decreasing the expression of active TGF-β1, α-SMA, collagen deposition, fibronectin and macrophage infiltration to the kidneys. Furthermore, intervention with C23 significantly decreased renal ferroptosis by reducing iron accumulation, increasing the expression of glutathione peroxidase 4 (GPX4) and lipid peroxidation in the kidneys of RIR-induced CKD mice. Treatment with C23 also attenuated BUN and creatinine. Finally, GFR was significantly decreased in RIR mice with left nephrectomy and C23 treatment partially prevented their decrease.ConclusionOur data show that eCIRP plays an important role in RIR-induced CKD. Treatment with C23 decreased renal inflammation, alleviated chronic renal injury and fibrosis, and inhibited ferroptosis in the RIR-induced CKD mice.

Pharmacological reduction of lipid hydroperoxides as a potential modulator of sarcopenia.

We previously reported that elevated expression of phospholipid hydroperoxide glutathione peroxidase 4, an enzyme that regulates membrane lipid hydroperoxides, can mitigate sarcopenia in mice. However, it is still unknown whether a pharmacological intervention designed to modulate lipid hydroperoxides might be an effective strategy to reduce sarcopenia in aged mice. Here we asked whether a newly developed compound, CMD-35647 (CMD), can reduce muscle atrophy induced by sciatic nerve transection. We treated mice daily with vehicle or CMD (15mg/kg, i.p. injection) starting 1day prior to denervation. CMD treatment reduced hydroperoxide generation and blunted muscle atrophy by over 17% in denervated muscle. To test whether CMD can reduce ageing-induced muscle atrophy and weakness, we treated mice with either vehicle or CMD (15mg/kg, i.p. injection) 3days per week for 8months, starting at 18months of age until 26months of age. We measured muscle mass, functional status of neuromuscular junctions, muscle contractile function and mitochondrial function in control and CMD-treated 26-month-old female mice. Treatment with CMD conferred protection against muscle atrophy in both tibialis anterior and extensor digitorum longus that was associated with maintenance of fibre size of MHC 2b and 2x fibres. Mitochondrial respiration was also protected in CMD-treated mice. We also found that muscle force generation was protected with CMD treatment despite denervation in ∼25% of the muscle fibres. Overall, this study shows that pharmacological interventions designed to reduce lipid hydroperoxides might be effective for preventing sarcopenia. KEY POINTS: Sarcopenia in aged mice is associated with muscle loss, contractile dysfunction, denervation, and reduced mitochondrial respiration. CMD-35647 is a pharmocological compound that can neutralize lipid hydroperoxides. 8 month treatment of CMD-35647 mitigated muscle atrophy in tibialis anterior and extensor digitorum longus. 8 month treatment of CMD-35647 improved muscle function in aged mice independent of the neuromuscular junction. Aged mice treated with CMD-35647 had greater respiration in red gastrocnemius muscle when compared to vehicle treated mice.

T-2 toxin triggers immunotoxic effects in goats by inducing ferroptosis and neutrophil extracellular traps.

T-2 toxin, a prevalent mycotoxin, represents a notable global public health risk. Neutrophil extracellular traps (NETs) and ferroptosis are involved in a variety of pathophysiological processes and are implicated in goat immunity. However, the impact of T-2 toxin on NETs release, ferroptosis, and their interplay have not been previously documented. In this study, neutrophils were stimulated with T-2 toxin for 4h. The structure and mechanism of NETs were analyzed using immunofluorescence and Pico Green staining. The expressions of glutathione peroxidase 4 (GPX4) and ferritin (FT) was quantified by qRT-PCR and western blotting. The levels of ROS and lipid ROS were assessed using DCFH-DA and C11 BODIPY 581/591 probes, and cellular mitochondria Fe2+ were detected by using Mito-FerroGreen probe. Inhibitors were utilized to explore the interaction between these two processes. The results confirmed that the T-2 toxin stimulated the NETs production, characterized by a structure co-modified by citrullinated histones (citH3), neutrophil elastase (NE) and DNA. Notably, significant inhibition of NETs production by T-2 toxin was observed with the NOX inhibitor DPI (P<0.001), the ERK inhibitor U0126 (P<0.001), the TLR2 inhibitor C29 (P<0.001), and the TLR4 inhibitor TLR4-IN-C34 (P<0.001). T-2 toxin triggered ferroptosis in neutrophils by suppressing GPX4 and FT expression, elevating ROS and lipid ROS, and augmenting the concentration of mitochondrial Fe2+. The ferroptosis inhibitor Fer-1 could rescue this induction; however, Fer-1 was unable to inhibit NETs which is induced by T-2 toxin. Conversely, T-2 toxin effectively triggered the downregulation of GPX4, which was counteracted by DPI, U0126, C29, and C34. This research elucidates the immunotoxic mechanisms of T-2 toxin in goat neutrophils and offers a novel perspective on preventing and treating T-2 toxin.

Sakuranetin Prevents Acetaminophen-Induced Liver Injury via Nrf2-Induced Inhibition of Hepatocyte Ferroptosis.

Oxidative stress is an important cause of acetaminophen (APAP)-induced liver injury (AILI). Sakuranetin (Sak) is an antitoxin from the cherry flavonoid plant with good antioxidant effects. However, whether sakuranetine has a protective effect on APAP-induced liver injury is not clear. Mouse and HepG2 cell models of APAP injury were used to investigate the effect of sakuranetin on AILI and its mechanism. Serum transaminase levels, histological changes, inflammatory mediators, oxidative stress, ferroptosis-related markers and Nrf2 signaling pathway proteins were analyzed. Sakuranetin significantly reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), as well as inflammatory factor; increased HepG2 activity and decreased cell death; inhibited ROS production, increased glutathione (GSH) content, expression of Glutathione Peroxidase 4 (GPX4) and Solute Carrier Family 7 Member 11 (SLC7A11), and decreased malondialdehyde and Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4) expression in mice and HepG2 cells after APAP treatment. Further analysis showed that sakuranetin induced the activation of the NFE2 Like BZIP Transcription Factor 2 (Nrf2) signaling pathway in liver tissue and HepG2 cells and promoted the nuclear translocation of Nrf2. Moreover, the hepatoprotective effect of sakuranetin and its inhibitory effect on ferroptosis were significantly attenuated by the Nrf2 inhibitor ML385. Sakuranetin alleviates AILI by activating the Nrf2 signaling pathway and inhibiting ferroptosis, and sakuranetin may be a potential therapeutic agent for the treatment of AILI.

JAG1/Notch Pathway Inhibition Induces Ferroptosis and Promotes Cataractogenesis.

Cataracts remain the leading cause of visual impairment worldwide, yet the underlying molecular mechanisms, particularly in age-related cataracts (ARCs), are not fully understood. The Notch signaling pathway, known for its critical role in various degenerative diseases, may also contribute to ARC pathogenesis, although its specific involvement is unclear. This study investigates the role of Notch signaling in regulating ferroptosis in lens epithelial cells (LECs) and its impact on ARC progression. RNA sequencing of anterior lens capsule samples from ARC patients revealed a significant downregulation of Notch signaling, coupled with an upregulation of ferroptosis-related genes. Notch1 expression decreased, while ferroptosis markers increased in an age-dependent manner. In vitro, upregulation of Notch signaling alleviated ferroptosis by decreasing ferritin heavy chain 1 (FTH1) and p53 levels while enhancing the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), glutathione peroxidase 4 (GPX4), and solute carrier family 7 member 11 (SLC7A11). Conversely, inhibition of Notch signaling exacerbated ferroptosis, as evidenced by reduced Nrf2, GPX4, and SLC7A11 expression. These findings suggest that downregulation of Notch signaling promotes ferroptosis in LECs by impairing the Nrf2/GPX4 antioxidant pathway, thereby contributing to ARC development. This study offers new insights into ARC pathogenesis and highlights the Notch signaling pathway as a potential therapeutic target for preventing or mitigating ARC progression.

Downregulation of the SREBP pathways and disruption of redox status by 25-hydroxycholesterol predispose cells to ferroptosis.

Enzymatically formed side-chain oxysterols function as signaling molecules regulating cholesterol homeostasis and act as intermediates in the biosynthesis of bile acids. In addition to these physiological functions, an imbalance in oxysterol homeostasis has been implicated in pathophysiology. Cholesterol 25-hydroxylase (CH25H) and its product 25-hydroxycholesterol (25-OHC), also formed by autoxidation, are associated with amyotrophic lateral sclerosis. However, the effects of 25-OHC on cell viability in glial cells remain unclear. This study demonstrates that 25-OHC induces ferroptosis, an iron-dependent programmed cell death, in mouse Schwann IMS32cells. Mechanistically, 25-OHC suppressed the expression of selenoprotein glutathione peroxidase 4 (GPX4) at both the transcriptional and translational levels by inhibiting the processing of sterol regulatory element-binding proteins (SREBPs). In addition, 25-OHC upregulated the expression of NADH-cytochrome b5 reductase 1 (CYB5R1) and NADPH-cytochrome P450 reductase (POR), enzymes that promote lipid peroxidation. We further found that 25-OHC increases the expression of glutathione-specific gamma-glutamylcyclotransferase 1 (CHAC1) and decreases glutathione levels. Importantly, non-cytotoxic concentrations of 25-OHC enhanced cellular sensitivity to ferroptosis inducers by downregulating GPX4 expression. These findings reveal a multifaceted approach whereby 25-OHC induces ferroptosis through SREBP pathway suppression and redox imbalance in mouse Schwann IMS32cells.

Protective effects of resveratrol on the expression of catalase, glutathione peroxidase, and superoxide dismutase genes in the ovary and their activity in the serum of rats exposed to lead acetate: An experimental study.

Lead (Pb) could be toxic to the female reproductive system, and resveratrol (Res) may overcome this toxicity. To investigate the Res impact on the catalase (Cat), glutathione peroxidase (Gpx), and superoxide dismutase (Sod) gene expression in the ovary and on the Cat and Gpx enzyme activity in the serum of rats exposed to lead acetate. In this experimental study, 33 female Wistar rats (8-10 wk, 180-200 gr) were divided into 6 groups: a control group (normal saline), a Res group (40 mg/kg), and a Pb group (lead acetate 30 mg/kg). 3 additional groups received lead acetate (30 mg/kg) with Res at 20, 40, and 80 mg/kg for 21 days. Gene expression of Cat, Gpx, and Sod was measured via qPCR, and serum Cat and Gpx activity was assessed using standard methods. Bioinformatics tools were used to evaluate Res effects on gene and protein function. Lead acetate significantly downregulates Cat, Gpx, and Sod gene expression, but Res significantly upregulates gene expression, especially at doses of 40 mg/kg for Cat, 20 mg/kg and 40 mg/kg for Gpx, and 80 mg/kg for Sod. Cat and Gpx enzyme activity increased and decreased in the lead acetate group, respectively. However, Res in all doses decreased only the Cat enzyme activity. Bioinformatics analysis indicates that Res can interact with the promoter regions and cavities of all 3 enzymes. Pb can dysregulate the expression and activity of the studied enzymes. However, the impact of Res is influenced by the dose, with 40 mg/kg frequently being the most effective.

Tianxiangdan (TXD) alleviates myocardial ischemia reperfusion-induced ferroptosis through the activation of estrogen receptor alpha (ERα).

Tianxiangdan (TXD), a traditional Chinese herbal remedy, demonstrates efficacy in mitigating myocardial ischemia-reperfusion (I/R)-induced damage. This study employed network pharmacology to evaluate the therapeutic targets and mechanisms of TXD in treating I/R. High-performance liquid chromatography-mass spectrometry (HPLC-MS) identified 86 compounds in TXD. Network pharmacological analysis predicted potential target genes and their modes of action. Cardiac function, ischaemic ST changes, lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD) activity, myocardial fiber, and infarct size were assessed using in vivo and in vitro I/R injury models. Estrogen receptor alpha (ERα) protein expression and estradiol (E2) levels were measured to confirm TXD's impact on estrogen levels and ERα expression. To examine if TXD reduces I/R injury through ERα, an AZD group (300 nmol·L-1 AZD9496 and 15% TXD serum) was compared to a TXD group (15% TXD serum). The study hypothesized that TXD upregulates the ERα-mediated iron metamorphosis pathway. I/R injury-induced ferroptosis was identified using a Fer-1 group (1.0 μmol·L-1 Fer-1 and 15% TXD serum) to elucidate the potential association between ferroptosis and ERα proteins. A DCFH-DA probe detected reactive oxygen species (ROS) and Fe2+, while Western blotting assessed target protein expression. Both in vitro and in vivo experiments demonstrated that TXD attenuated I/R injury by reducing elevated ST-segment levels, improving cardiac injury biomarkers (LDH, MDA, and SOD), alleviating pathological features, and preventing I/R-induced loss of cell viability in vitro. The effects and mechanisms of TXD on I/R injury-associated ferroptosis were investigated using I/R-induced H9c2 cells. The TXD group showed significantly decreased ROS and Fe2+ levels, while the AZ group (treated with AZD9496) exhibited increased levels. The TXD group demonstrated enhanced expression of ERα and glutathione peroxidase 4 (GPX4), with reduced levels of P53 protein and ferritin-heavy polypeptide 1 (FTH1). The AZ group exhibited contrasting effects on these expression levels. The literature indicated a novel connection between ERα and ferroptosis. TXD activates the ERα signaling pathway, promoting protection against I/R-induced myocardial cell ferroptosis. This study provides evidence supporting TXD use for myocardial ischemia treatment, particularly in older female patients who may benefit from its therapeutic outcomes.