Altered Redox Status Research Articles

Carvacrol attenuated haloperidol-induced Parkinson’s disease via TNF/NFκβ-NLRP3-mediated pyroptosis

BackgroundParkinson’s disease is a debilitating and the second most common neurodegenerative disorder with a high prevalence. Parkinson’s disease has a multifaceted etiology characterized by an altered redox state and an excessive inflammatory response. In this study, we investigated the potential neuroprotective properties of carvacrol in a haloperidol-induced Parkinson’s model. In female Sprague-Dawley rats, the animal Parkinson model was induced by intraperitoneally administering 1 mg / kg of haloperidol once daily for fifteen days. Carvacrol was administered at a dose of 25 and 50 mg / kg once daily for fifteen days before haloperidol administration. In order to further illustrate the vital role of the tumor necrosis factor (TNF-α) pathway, we administered 50 mg / kg of the TNF-α inhibitor thalidomide once daily for 15 days.ResultsOur results showed that haloperidol-induced motor deficits, changed endogenous antioxidant enzymes, along with higher levels of inflammasome (NLRP3) and other inflammatory mediators. Moreover, increased levels of lipid peroxidase (LPO) indicated a significant rise in oxidative stress due to haloperidol. Moreover, carvacrol reduced these effects by preventing pyroptosis mediated by the inflammasome (NLRP3) and TNF-α. The administration of thalidomide mitigated oxidative stress and suppresses inflammatory pathways through the augmentation of the intrinsic antioxidant system. Further, co-treatment of carvacrol with thalidomide synergized the neuroprotective effect of carvacrol as demonstrated by various immunoassays and histology analyses.ConclusionsTaken together, our findings suggest that carvacrol mitigated haloperidol-induced Parkinson-like symptoms, partially through the downregulation of TNF-α and NLRP3.

Oxidative Score and Microvesicle Profile Suggest Cardiovascular Risk in Chronic Kidney Disease

Chronic kidney disease (CKD) is associated with a high incidence of cardiovascular disease (CVD) due to the accumulation of uremic toxins, altered redox state, and chronic systemic inflammation. This study aimed to analyze the relationship between the redox status of patients with CKD and the phenotype of microvesicles (MVs) subtypes, and cardiovascular events. The oxidative stress level of each participant was determined using an individualized OXY-SCORE. The relationship between pro-oxidant and antioxidant parameters and the expression of membrane markers in endothelial-derived microvesicles (EMVs) and platelet-derived microvesicles (PMVs) was established. Patients with advanced CKD (ACKD) and hemodialysis (HD) had a higher OXY-SCORE than healthy subjects (HS), whereas peritoneal dialysis (PD) patients had similar scores to HS. PD patients showed elevated PMVs and CD41 expression, whereas HD patients had higher EMVs and CD31 expression. Patients with ACKD had higher tissue factor (TF) expression in the PMVs and EMVs. TF expression was correlated with xanthine oxidase (XO) activity and was negatively correlated with antioxidant parameters. Patients with cardiovascular events show elevated TF. In conclusion, microvesicles and oxidative stress may serve as markers of cardiovascular risk in CKD, with TF expression in PMVs and EMVs being potential predictive and prognostic biomarkers of CVD.

Abstract TP336: Neuropathological changes in the chronic phase of ischemic stroke are marked by persistent alteration of microglial function and neurodegenerative phenotypes

Improvements in acute stroke treatment, including EVT and critical care management, have increased survival rates post-stroke. However, many stroke survivors have significant post-stroke disability and cognitive impairment. Despite this, the chronic progression and long-term sequelae of ischemic stroke pathology remains understudied. Methods: We examined the chronicity of neurobehavioral recovery and progressive neuropathology in young male (3 month) and middle-aged male and female (14 month) C57Bl/6 mice at 3 and 6 months after a 60-minute transient middle cerebral artery occlusion (tMCAO) or sham surgery ( n = 10-20/group ). Behavioral testing included NORT, fear conditioning (FC), and tail suspension. Immunohistochemistry (IHC) was performed on mouse brains, as well as post-mortem human brain samples from patients with a chronic infarct ( n = 6/group ), to assess demyelination (MBP), neuronal apoptosis (TUNEL/NeuN), and amyloid burden (Aβ-42). Flow cytometry was performed on the ipsilateral mouse brain hemisphere. RNA isolated from the ipsilateral hemisphere was sent for gene profiling. Results: In both young and middle-aged mice, depressive-like behavior persisted for 6 months post-stroke (PS) (p= <0.0001), while cognitive function progressively worsened from 3 to 6 months, as seen by a reduction in the NORT (p=.0063) and FC (p=.0084). MRI imaging and IHC revealed cerebral atrophy, significant demyelination (mouse, p=.0361; human, p =.0001), and increased microglial density (p=.0059) in the hippocampus of both human and mice. TUNEL/NeuN staining showed ongoing neuronal degeneration in the human hippocampus, distal to the chronic infarct. Human chronic stroke hippocampus had increased amyloid burden compared to age-matched controls (p=.0677). Cytometric anyalses revealed disease-associated microglial (DAM) phenotypes were marked by increased senescence, cytokine production, and an altered redox state. Transcriptomic data showed significant chronic upregulation of DAM genes. Conclusion: Our findings demonstrate that ischemic stroke accelerates inflamm-aging and premature senescence within the chronic infarct microenvironment. Cellular senescence and chronic disease signatures may contribute to progressive cognitive impairment post-stroke. Identification of secondary injury processes, and late pathological events post-stroke, allude to a neurodegenerative etiology and may offer viable targets for delayed treatment to prevent further neurological decline.

A Droplet Microfluidic Sensor for Point-of-Care Measurement of Plasma/Serum Total Free Thiol Concentrations.

Total free thiols are an important marker of the whole-body redox state, which has been shown to be associated with clinical outcome in health and disease. Recent investigations have suggested that increased insight may be gained by monitoring alterations of redox state in response to exercise and hypoxia and to monitor redox trajectories in disease settings. However, conducting such studies is challenging due to the requirement for repeated venous blood sampling and intensive lab work. Droplet microfluidic sensors offer an alternative platform for developing a point-of-care testing approach using small sample volumes and automated systems to complement or ultimately replace laboratory testing. Here we developed a small, portable droplet microfluidic sensor that can measure total free thiol concentrations in 20 μL human plasma (or serum) samples, providing a reading in less than 10 min. This system features a novel method to enhance the mixing of reagent and analyte in droplets containing viscous biological fluids. The results in a range of real-world human plasma samples showed equivalence with current standard laboratory assays while reducing sample volume requirements 9-fold and fully automating the process. Micro hematocrit capillaries allowed testing of capillary blood samples collected by fingerprick lancing. The system was used to monitor total free thiols using fingerprick samples in healthy volunteers and revealed significant changes in total free thiols in response to food intake and exercise. This device has the potential to improve our ability to conduct physiological studies of total free thiol level changes and improve our understanding of redox physiology, which may ultimately be applied in redox medicine to improve patient care.

Irisin-mediated KEAP1 degradation alleviates oxidative stress and ameliorates pancreatitis.

Oxidative stress (OS) injury is pivotal in acute pancreatitis (AP) pathogenesis, contributing to inflammatory cascades. Irisin, a ubiquitous cytokine, exhibits antioxidant properties. However, the role of irisin in AP remains inconclusive. Our study aims to elucidate irisin expression in AP patients and investigate its mechanism of action to propose a novel treatment strategy for AP. Serum irisin levels in 65 AP patients were quantified using an enzyme-linked immunosorbent assay and correlated with disease severity scores. Core genes implicated in AP-related oxidative stress were identified and screened via bioinformatics analysis. The therapeutic efficacy of irisin in AP was confirmed using a murine cerulein-induced AP model. The intrinsic mechanism of irisin's antioxidative stress action was investigated and verified in pancreatic AR42J cells (Supplementary Fig.1). Common targets shared by irisin and AP were further validated using a molecular docking model which was constructed for virtual docking analysis. This study investigated alterations in redox status in AP and found a significant reduction in serum irisin levels, correlating inversely with AP severity. In a murine AP model, we showed that irisin triggers an antioxidative stress program via the KEAP1 gene; this process helps reestablish redox balance by decreasing the buildup of reactive oxygen species (ROS) and suppressing the secretion of inflammatory mediators within pancreatic tissues Notably, increased KEAP1 expression counteracted the antioxidative effects of irisin. Our findings unveil a novel therapeutic mechanism for AP, wherein irisin inhibits KEAP1 to alleviate OS. Increasing irisin levels in vivo presents a promising strategy for AP treatment.

The Effect of a Secondary Stressor on the Morphology and Membrane Structure of an Already Challenged Maternal and Foetal Red Blood Cell Population.

The red blood cell (RBC) membrane is unique and crucial for maintaining structural-functional relationships. Maternal smoking induces significant changes in the morphological, rheological, and functional parameters of both maternal and foetal RBCs, mainly due to the continuous generation of the free radicals. The major aim of this study was to follow the consequences of a secondary stressor, like fungal infection, on the already compromised RBC populations. The impact of Candida infection, a growing health concern, was investigated on four blood sample groups: mothers and their neonates originating from non-smoking versus smoking populations. Here, we searched for phenotypical and molecular markers that precisely reflected the effect of Candida infection on the RBC membrane; this included the level of hemolysis, appearance of morphological variants, formation of the lipid peroxidation marker 4-hydroxyl-nonenal, arrangement of the Band 3 molecules and activation of the Caspase 3. In most of the examined cases, the fungal infection increased the adverse symptoms induced by smoking, indicating a general stress response, likely due to an altered redox state of the cells. However, we were able to identify an atypical phenotype (clustered populations with shrinkage and membrane blebbing) in both the non-smoking and smoking populations, which might be a unique marker for Candida spp. infection.

Exploring the Therapeutic Potential of Cannabidiol in U87MG Cells: Effects on Autophagy and NRF2 Pathway.

Cannabinoids include both endogenous endocannabinoids and exogenous phytocannabinoids, such as cannabidiol (CBD), and have potential as therapeutic agents in cancer treatment due to their selective anticancer activities. CBD exhibits both antioxidant and pro-oxidant effects depending on its concentration and cell types. These properties allow CBD to influence oxidative stress responses and potentially enhance the efficacy of antitumor therapies. In this study, we treated U87MG glioma cells with low dose (1 μM) CBD and evaluated its molecular effects. Our findings indicate that CBD reduced cell viability by 20% (p < 0.05) through the alteration of mitochondrial membrane potential. The alteration of redox status by CBD caused an attempt to rescue mitochondrial functionality through nuclear localization of the GABP transcription factor involved in mitochondria biogenesis. Moreover, CBD treatment caused an increase in autophagic flux, as supported by the increase in Beclin-1 and the ratio of LC3-II/LC3-I. Due to mitochondria functionality alteration, pro-apoptotic proteins were induced without activating apoptotic effectors Caspase-3 or Caspase-7. The study of the transcription factor NRF2 and the ubiquitin-binding protein p62 expression revealed an increase in their levels in CBD-treated cells. In conclusion, low-dose CBD makes U87MG cells more vulnerable to cytotoxic effects, reducing cell viability and mitochondrial dynamics while increasing autophagic flux and redox systems. This explains the mechanisms by which glioma cells respond to CBD treatment. These findings highlight the therapeutic potential of CBD, suggesting that modulating NRF2 and autophagy pathways could represent a promising strategy for glioblastoma treatment.

Paired analysis of host and pathogen genomes identifies determinants of human tuberculosis

Infectious disease is the result of interactions between host and pathogen and can depend on genetic variations in both. We conduct a genome-to-genome study of paired human and Mycobacterium tuberculosis genomes from a cohort of 1556 tuberculosis patients in Lima, Peru. We identify an association between a human intronic variant (rs3130660, OR = 10.06, 95%CI: 4.87 − 20.77, P = 7.92 × 10−8) in the FLOT1 gene and a subclavaluee of Mtb Lineage 2. In a human macrophage infection model, we observe hosts with the rs3130660-A allele exhibited stronger interferon gene signatures. The interacting strains have altered redox states due to a thioredoxin reductase mutation. We investigate this association in a 2020 cohort of 699 patients recruited during the COVID-19 pandemic. While the prevalence of the interacting strain almost doubled between 2010 and 2020, its infection is not associated with rs3130660 in this recent cohort. These findings suggest a complex interplay among host, pathogen, and environmental factors in tuberculosis dynamics.

Advances in myocardial energy metabolism: metabolic remodelling in heart failure and beyond.

The very high energy demand of the heart is primarily met by adenosine triphosphate (ATP) production from mitochondrial oxidative phosphorylation, with glycolysis providing a smaller amount of ATP production. This ATP production is markedly altered in heart failure, primarily due to a decrease in mitochondrial oxidative metabolism. Although an increase in glycolytic ATP production partly compensates for the decrease in mitochondrial ATP production, the failing heart faces an energy deficit that contributes to the severity of contractile dysfunction. The relative contribution of the different fuels for mitochondrial ATP production dramatically changes in the failing heart, which depends to a large extent on the type of heart failure. A common metabolic defect in all forms of heart failure [including heart failure with reduced ejection fraction (HFrEF), heart failure with preserved EF (HFpEF), and diabetic cardiomyopathies] is a decrease in mitochondrial oxidation of pyruvate originating from glucose (i.e. glucose oxidation). This decrease in glucose oxidation occurs regardless of whether glycolysis is increased, resulting in an uncoupling of glycolysis from glucose oxidation that can decrease cardiac efficiency. The mitochondrial oxidation of fatty acids by the heart increases or decreases, depending on the type of heart failure. For instance, in HFpEF and diabetic cardiomyopathies myocardial fatty acid oxidation increases, while in HFrEF myocardial fatty acid oxidation either decreases or remains unchanged. The oxidation of ketones (which provides the failing heart with an important energy source) also differs depending on the type of heart failure, being increased in HFrEF, and decreased in HFpEF and diabetic cardiomyopathies. The alterations in mitochondrial oxidative metabolism and glycolysis in the failing heart are due to transcriptional changes in key enzymes involved in the metabolic pathways, as well as alterations in redox state, metabolic signalling and post-translational epigenetic changes in energy metabolic enzymes. Of importance, targeting the mitochondrial energy metabolic pathways has emerged as a novel therapeutic approach to improving cardiac function and cardiac efficiency in the failing heart.

A short duration of mechanical ventilation alters redox status in the diaphragm and aggravates inflammation in septic mice

BackgroundMechanical ventilation (MV) is a life support method used to treat patients with respiratory failure. High tidal volumes during MV can cause ventilator-induced lung injury (VILI), but also affect other organs, such as the diaphragm (Dia) causing ventilator-induced diaphragmatic dysfunction (VIDD). VIDD is often associated with a complicated course on MV. Sepsis can induce inflammation and oxidative stress, contributing to the impairment of the Dia and worsening of the prognosis. This study evaluated the additive or synergistic effects of a short course of mechanical ventilation on Dia in healthy and septic adult mice. Methods32 adult male C57BL/6 mice were randomly into four groups: Control (CG), non-ventilated animals instilled with saline solution (PBS1x); Lipopolysaccharide (LPS), non-ventilated animals instilled with PBS solution containing lipopolysaccharide; Mechanical Ventilation (MV) for 1 h, ventilated animals instilled with PBS solution; and Mechanical Ventilation and LPS (MV+LPS), ventilated animals instilled with PBS solution containing LPS. At the end of the experimental protocol, the animals were euthanized, then blood and diaphragm tissue samples were collected. ResultsEvaluation of leukocyte/blood parameters and diaphragm muscle showed that MV, LPS and the combination of both were able to increase neutrophil count, creatine kinase, inflammatory mediators and oxidative stress in all groups compared to the control. MV and sepsis combined had additive effects on inflammation and lipid peroxidation. ConclusionsA short course of Mechanical ventilation promotes inflammation and oxidative stress and, its combination with sepsis further increases local and systemic inflammation.

The Interplay of Carveol and All-Trans Retinoic Acid (ATRA) in Experimental Parkinson's Disease: Role of Inflammasome-Mediated Pyroptosis and Nrf2.

Parkinson's disease (PD) is a debilitating and the second most common neurodegenerative disorder with a high prevalence. PD has a multifaceted etiology characterized by an altered redox state and an excessive inflammatory response. Extensive research has consistently demonstrated the role of the nuclear factor E2-related factor (Nrf2) and inflammasomes, notably NLRP3 in neurodegenerative diseases. In this study, our focus was on exploring the potential neuroprotective properties of carveol in Parkinson's disease. Our findings suggest that carveol may exhibit these effects through Nrf2 and by suppressing pyroptosis. Male albino mice were treated with carveol, and the animal PD model was induced through a single intranigral dose of 2µg/2µl lipopolysaccharide (LPS). To further demonstrate the essential role of the Nrf2 pathway, we utilized all-trans retinoic acid (ATRA) to inhibit the Nrf2. Our finding showed the induction of pyroptosis as evidenced by increased levels of NLRP3 and other inflammatory mediators, including IL-1β, iNOS, p-NFKB, and apoptotic cell death indicated by positive fluoro Jade B (FJB) staining. Moreover, increased levels of lipid peroxides and reactive oxygen species indicated a significant rise in oxidative stress due to LPS. The administration of carveol mitigates oxidative stress and suppresses inflammatory pathways through the augmentation of intrinsic antioxidant defenses, primarily via the activation of the Nrf2. Conversely, ATRA reversed carveol protective effects by increasing FJB-positive cells, inflammatory and oxidative biomarkers. Taken together, our findings suggest that carveol mitigated LPS-induced Parkinson-like symptoms, partially through the activation of the Nrf2 and downregulation of pyroptosis notably NLRP3.

MicroRNA mediated suppression of airway lactoperoxidase by TGF-β1 and cigarette smoke promotes airway inflammation

Transforming Growth Factor Beta1 (TGF-β1) signaling is upregulated in Chronic Obstructive Pulmonary disease (COPD), smokers, and people living with HIV. Cigarette smoking and HIV are also independent risk factors for COPD. Chronic inflammation is a hallmark of COPD. However, the underlying mechanisms remain unknown. Previous research has suggested that TGF-β1 alters the airway epithelial microRNAome and transcriptome, potentially contributing to lung inflammation. The Lactoperoxidase (LPO) system is an integral component of innate immunity within the airway. LPO plays a crucial role in host defense by catalyzing the oxidation of thiocyanate to hypothiocyanite in the presence of hydrogen peroxide (H2O2), generating a potent antibacterial and antiviral agent. Additionally, the LPO system potentially aids in maintaining cellular redox balance by reducing the levels of H2O2, thus mitigating oxidative stress within the airway epithelium. LPO dysfunction can impair immune responses and exacerbate inflammatory processes in respiratory diseases.In this study, primary bronchial epithelial cells and bronchial cell lines were treated with TGF-β1 and exposed to cigarette smoke to characterize the effect of these factors on LPO and their downstream effects. RT-qPCR and Western Blot were applied to quantify mRNA and proteins’ expression. The levels of H2O2 were detected using the Amplex Red Assay. Magnetofection and transfection were applied to probe the effect of miR-449b-5p. Staining procedures using the MitoTracker Green and C12FDG dyes were used to establish mitochondria mass and senescence. The levels of pro-inflammatory cytokines were measured via Luminex assays.We found that TGF-β1 and cigarette smoke suppressed airway LPO expression, increasing H2O2 levels. This increase in H2O2 had downstream effects on mitochondrial homeostasis, epithelial cellular senescence, and the pro-inflammatory cytokine response. We demonstrate for the first time that airway LPO is regulated by TGF-β1-induced miRNA-mediated post-transcriptional silencing through miR-449b-5p in the lungs. Further, we identify and validate miR-449-5p as the candidate miRNA upregulated by TGF-β1, which is involved in LPO suppression. This paper demonstrates a new mechanism by which TGF-β1 can lead to altered redox status in the airway.

Tumor Microenvironment-Responsive Magnetotactic Bacteria-Based Multi-Drug Delivery Platform for MRI-Visualized Tumor Photothermal Chemodynamic Therapy.

Cancer cells display elevated reactive oxygen species (ROS) and altered redox status. Herein, based on these characteristics, we present a multi-drug delivery platform, AMB@PDAP-Fe (APPF), from the magnetotactic bacterium AMB-1 and realize MRI-visualized tumor-microenvironment-responsive photothermal-chemodynamic therapy. The Fe3+ in PDAP-Fe is reduced by the GSH at the tumor site and is released in the form of highly active Fe2+, which catalyzes the generation of ROS through the Fenton reaction and inhibits tumor growth. At the same time, the significant absorption of the mineralized magnetosomes in AMB-1 cells in the NIR region enables them to efficiently convert near-infrared light into heat energy for photothermal therapy (PTT), to which PDAP also contributes. The heat generated in the PTT process accelerates the process of Fe2+ release, thereby achieving an enhanced Fenton reaction in the tumor microenvironment. In addition, the magnetosomes in AMB-1 are used as an MRI contrast agent, and the curing process is visualized. This tumor microenvironment-responsive MTB-based multi-drug delivery platform displays the potency to combat tumors and demonstrates the utility and practicality of understanding the cooperative molecular mechanism when designing multi-drug combination therapies.

Mitohormesis during advanced stages of Duchenne muscular dystrophy reveals a redox-sensitive creatine pathway that can be enhanced by the mitochondrial-targeting peptide SBT-20

Mitochondrial creatine kinase (mtCK) regulates the “fast” export of phosphocreatine to support cytoplasmic phosphorylation of ADP to ATP which is more rapid than direct ATP export. Such “creatine-dependent” phosphate shuttling is attenuated in several muscles, including the heart, of the D2.mdx mouse model of Duchenne muscular dystrophy at only 4 weeks of age. However, the degree to which creatine-dependent and -independent systems of phosphate shuttling progressively worsen or potentially adapt in a hormetic manner throughout disease progression remains unknown. Here, we performed a series of proof-of-principle investigations designed to determine how phosphate shuttling pathways worsen or adapt in later disease stages in D2.mdx (12 months of age). We also determined whether changes in creatine-dependent phosphate shuttling are linked to alterations in mtCK thiol redox state. In permeabilized muscle fibres prepared from cardiac left ventricles, we found that 12-month-old male D2.mdx mice have reduced creatine-dependent pyruvate oxidation and elevated complex I-supported H2O2 emission (mH2O2). Surprisingly, creatine-independent ADP-stimulated respiration was increased and mH2O2 was lowered suggesting that impairments in the faster mtCK-mediated phosphocreatine export system resulted in compensation of the alternative slower pathway of ATP export. The apparent impairments in mtCK-dependent bioenergetics occurred independent of mtCK protein content but were related to greater thiol oxidation of mtCK and a more oxidized cellular environment (lower GSH:GSSG). Next, we performed a proof-of-principle study to determine whether creatine-dependent bioenergetics could be enhanced through chronic administration of the mitochondrial-targeting, ROS-lowering tetrapeptide, SBT-20. We found that 12 weeks of daily treatment with SBT-20 (from day 4–∼12 weeks of age) increased respiration and lowered mH2O2 only in the presence of creatine in D2.mdx mice without affecting calcium-induced mitochondrial permeability transition activity. In summary, creatine-dependent mitochondrial bioenergetics are attenuated in older D2.mdx mice in relation to mtCK thiol oxidation that seem to be countered by increased creatine-independent phosphate shuttling as a unique form of mitohormesis. Separate results demonstrate that creatine-dependent bioenergetics can also be enhanced with a ROS-lowering mitochondrial-targeting peptide. These results demonstrate a specific relationship between redox stress and mitochondrial hormetic reprogramming during dystrophin deficiency with proof-of-principle evidence that creatine-dependent bioenergetics could be modified with mitochondrial-targeting small peptide therapeutics.

Peroxiredoxin 2 regulates DAF-16/FOXO mediated mitochondrial remodelling in response to exercise that is disrupted in ageing

ObjectivesA decline in mitochondrial function and increased susceptibility to oxidative stress is a hallmark of ageing. Exercise endogenously generates reactive oxygen species (ROS) in skeletal muscle and promotes mitochondrial remodelling resulting in improved mitochondrial function. It is unclear how exercise induced redox signalling results in alterations in mitochondrial dynamics and morphology. MethodsIn this study, a Caenorhabditis elegans model of exercise and ageing was used to determine the mechanistic role of Peroxiredoxin 2 (PRDX-2) in regulating mitochondrial morphology. Mitochondrial morphology was analysed using transgenic reporter strains and transmission electron microscopy, complimented with the analysis of the effects of ageing and exercise on physiological activity. ResultsThe redox state of PRDX-2 was altered with exercise and ageing, hyperoxidised peroxiredoxins were detected in old worms along with basally elevated intracellular ROS. Exercise generated intracellular ROS and rapid mitochondrial remodelling, which was disrupted with age. The exercise intervention promoted mitochondrial ER contact sites (MERCS) assembly and increased DAF-16/FOXO nuclear localisation. The prdx-2 mutant strain had a disrupted mitochondrial network as evidenced by increased mitochondrial fragmentation. In the prdx-2 mutant strain, exercise did not activate DAF-16/FOXO, mitophagy or increase MERCS assembly. The results demonstrate that exercise generated ROS increased DAF-16/FOXO transcription factor nuclear localisation required for activation of mitochondrial fusion events that were blunted with age. ConclusionsThe data demonstrate the critical role of PRDX-2 in orchestrating mitochondrial remodelling in response to a physiological stress by regulating redox dependent DAF-16/FOXO nuclear localisation.

ABCC2 induces metabolic vulnerability and cellular ferroptosis via enhanced glutathione efflux in gastric cancer.

Although it is traditionally believed that ATP binding cassette subfamily C member 2 (ABCC2) is a multidrug resistance-associated protein correlated with a worse prognosis, our previous and several other studies demonstrated the contrary to be true in gastric cancer (GC). We aim to explore the underlying mechanism of this discovery. Our study utilized whole-exome sequencing (WES), RNA sequencing, and droplet digital PCR (ddPCR) analysis of 80 gastric cancer samples, along with comprehensive immunohistochemical (IHC) analysis of 1044 human GC tissue samples.By utilizing CRISPRCas9 to genetically modify cell lines with the ABCC2-24C > T (rs717620) point mutation and conducting dual-luciferase reporter assays, we identified that transcription factors SOX9 and ETS1 serve as negative regulators of ABCC2 expression. Seahorse assay and mass spectrometry were used to discover altered metabolic patterns. Gain and loss-of-function experiments in GC cell lines and preclinical models were carried out to validate ABCC2 biological function. ABCC2 high expression correlated with better prognosis, and rs717620 can influence ABCC2 expression by disrupting the binding of ETS1 and SOX9. Gain and loss-of-function experiments in GC cell lines demonstrated amino acid deprivation reduces proliferation, migration, and drug resistance in ABCC2-high GC cells. ABCC2 leads to reduced intracellular amino acid pools and disruption of cellular energy metabolism. This phenomenon depended on ABCC2-mediated GSH extrusion, resulting in alterations in redox status, thereby increasing the cell's susceptibility to ferroptosis. Furthermore, patient-derived organoids and patient-derived tumor-like cell clusters were used to observe impact of ABCC2 on therapeutic effect. In the xenograft model with high ABCC2 expression, we observed that constricting amino acid intake in conjunction with GPX4 inactivation resulted in notable tumor regression. Our findings demonstrate a significant role of ABCC2 in amino acid metabolism and ferroptosis by mediating GSH efflux in GC. This discovery underlines the potential of combining multiple ferroptosis targets as a promising therapeutic strategy for GC with high ABCC2 expression. ABCC2 plays a crucial role in inducing metabolic vulnerability and ferroptosis in gastric cancer through enhanced glutathione efflux. The ABCC2 24C > T polymorphism is a key factor influencing its expression. These results highlight the potential of ABCC2 as a predictive biomarker and therapeutic target in gastric cancer.

Protective Effects of Curcumin and its Analogues via the Nrf2 Pathway in Metabolic Syndrome.

Metabolic Syndrome (MetS) refers to a set of medical conditions including insulin resistance, central obesity, atherogenic dyslipidemia, and hypertension. Due to these dysregulations, if not treated, MetS could increase the risk of CVA, CVD, and diabetes. As described by WHO, CVD is the leading cause of mortality in the world which motivates researchers to investigate the management of its risk factors, especially MetS. It is reported that oxidative stress secondary to the abundant generation of free radicals oxygen species (ROS) and the ensuing altered redox status play an important role as a mediator in MetS. As a result, using new antioxidant agents with higher bioavailability has been proposed as an efficient treatment. Curcumin (a polyphenol of the diarylheptanoids class), which is used as a traditional medicine for various diseases including cardiovascular diseases and diabetes, is characterized by its antioxidant properties which, at least in part, are mediated via the activation of the Nrf2/ARE signaling pathway. Nrf2 is a transcription factor that plays a key role in regulating internal defense systems and increases antioxidant levels to decrease oxidative damage and cell apoptosis. Nrf2 expression and stability are enhanced by curcumin, leading to a higher rate of Nrf2 migration to the cell nucleus to regulate ARE gene expression, thus protecting cells against oxidative stress. In this article, we provide a comprehensive review of the molecular effect of curcumin and its derivatives via Nrf2 regulation in several conditions, such as diabetes, hypertension, dyslipidemia, and obesity.

P-082 Use of TetraSOD® in male infertility: double-blind randomized placebo-controlled study

Abstract Study question Can the use of TetraSOD® (microalgae with high content of the antioxidant enzyme superoxide dismutase) improve semen quality and reduce oxidative stress in sperm? Summary answer The use of TetraSOD® reduces the oxidative stress of sperm, increasing the total sperm count in oligozoospermia and reducing the double-stranded DNA sperm fragmentation. What is known already Male factor is present in approximately 50% of the infertile couples, a large number of them of unknown or idiopathic origin. It has been demonstrated that semen quality is deteriorating over time, perhaps as a result of exposure to several environmental factors related with lifestyle that could impact both directly and indirectly on the complex process of spermatogenesis. Some of these bad habits of lifestyle increase the levels of oxidative stress in semen, which is associated with lower sperm concentration and motility. In this scenario, the use of antioxidants can be useful to increase sperm quality. Study design, size, duration Double-blind randomized placebo-controlled clinical study to assess the effect of 250 mg of TetraSOD® (microalgae with high content of the primary antioxidant enzyme superoxide dismutase). Eighty patients with idiopathic infertility showing asthenozoospermia, oligozoospermia or oligoasthenozoospermia were recruited and randomized to receive 250 mg of TetraSOD® (TSOD group) or placebo (Placebo group) for 3 months. Participants/materials, setting, methods Men with asthenozoospermia, oligozoospemia or aligoastenozoospermia and idiopatic infertility were recruited after informed consent signature. Patients were randomized into two groups. TetraSOD® group received 250 mg of TetraSOD®during 3 months, and Placebo group received capsules without TetraSOD® during the same period of time. Seminogram, double-strand sperm DNA fragmentation (COMET assay) and sORP (static oxidation- reduction potential) were studied at baseline (V0) and after 3 months (V3). Main results and the role of chance TetraSOD® consumption for three months elicited a statistically significant increase (Wilcoxon matched-pairs signed rank test; p=0.02) in the average number of sperms per ejaculate (from 17.06 x 106 to 41.94 x 106) in participants displaying oligozoospermia (&amp;lt;39 x 106 sperms) at V0. In contrast, the lower variation in the measured values in the Placebo group was not statistically significant. Regarding sORP, a statistically significant decrease (Wilcoxon matched-pairs signed rank test; p=0.0233) was observed in participants who displayed a value at V0 between 1.34-10. After TetraSOD® consumption, the average changed from 2.96 to 1.91 mv/106 sperm/ml from V0 to V3. However, not statistically significant changes were detected in the Placebo group between sORP values at V0 and V3. Moreover, in relation to double-stranded DNA breaks, a statistically significant decrease (Wilcoxon matched-pairs signed rank test; p=0.01) in the average percentages (from 31.81% to 25.93%) was measured after consumption of TetraSOD® at V3 in participants displaying a compromised redox status (sORP&amp;gt;1.34-10) at V0. No significant changes were found in the Placebo group. Limitations, reasons for caution The study was performed only in one ethnic group, so in future studies other ethnicities should be included. Wider implications of the findings TetraSOD® may improve male fertility because increases the number of sperms per ejaculate in oligozoospermia and reduces double-stranded DNA fragmentation in sperm when individuals display an altered redox status in semen. Such results might be related to the indirect antioxidant effect of TetraSOD®, reducing oxidative stress in seminal fluid. Trial registration number Not applicable

New perspectives on the role of biological factors in anorexia nervosa: Brain volume reduction or oxidative stress, which came first?

Anorexia nervosa (AN) is an eating disorder (ED) that has seen an increase in its incidence in the last thirty years. Compared to other psychosomatic disorders, ED can be responsible for many major medical complications, moreover, in addition to the various systemic impairments, patients with AN undergo morphological and physiological changes affecting the cerebral cortex. Through immunohistochemical studies on portions of postmortem human brain of people affected by AN and healthy individuals, and western blot studies on leucocytes of young patients and healthy controls, this study investigated the role in the afore-mentioned processes of altered redox state. The results showed that the brain volume reduction in AN could be due to an increase in the rate of cell death, mainly by apoptosis, in which mitochondria, main cellular organelles affected by a decreased dietary intake, and a highly compromised intracellular redox balance, may play a pivotal role

Salvia hispanica L. (chia) seed improves redox state and reverts extracellular matrix collagen deposition in skeletal muscle of sucrose-rich diet-fed rats.

Skeletal muscle (SkM) is a plastic and dynamic tissue, essential in energy metabolism. Growing evidence suggests a close relationship between intramuscular fat accumulation, oxidative stress (OS), extracellular matrix (ECM) remodeling, and metabolic deregulation in SkM. Nowadays natural products emerge as promising alternatives for the treatment of metabolic disorders. We have previously shown that chia seed administration reverts SkM lipotoxicity and whole-body insulin resistant (IR) in sucrose-rich diet (SRD) fed rats. The purpose of the present study was to assess the involvement of OS and fibrosis in SkM metabolic impairment of insulin-resistant rats fed a long-term SRD and the effects of chia seed upon these mechanisms as therapeutic strategy. Results showed that insulin-resistant SRD-fed rats exhibited sarcopenia, increase in lipid peroxidation, altered redox state, and ECM remodeling-increased collagen deposition and lower activity of the metalloproteinase 2 (MMP-2) in SkM. Chia seed increased ferric ion reducing antioxidant power and glutathione reduced form levels, and the activities of glutathione peroxidase and glutathione reductase enzymes. Moreover, chia seed reversed fibrosis and restored the MMP-2 activity. This work reveals a participation of the OS and ECM remodeling in the metabolic alterations of SkM in our experimental model. Moreover, current data show novel properties of chia seed with the potential to attenuate SkM OS and fibrosis, hallmark of insulin-resistant muscle.