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CeOx-Induced Spatial and Electronic Modulation for General Direct Oxo Coupling in Transition Metal Hydroxides.

Electrochemical water splitting has emerged as a sustainable paradigm for hydrogen generation, where sluggish kinetics of the oxygen evolution reaction (OER) catalyzed by transition metal-based materials remain the critical bottleneck. Herein, we present a strategy that anchors CeOx nanoparticles (∼2 nm) onto two-dimensional Ni(OH)2 nanosheets, enabling dual modulation of spatial configuration and electronic states to accelerate O-O coupling. Spatially, interfacial lattice distortion between CeOx and Ni(OH)2 optimizes Ni-Ni dual-metal sites with reduced interatomic spacing. Electronically, dynamic modulation through reversible Ce3+/Ce4+ redox cycling positions Ce as an electronic regulation hub, stabilizing Ni species at the catalytically favorable +3 oxidation state through Ce─O─Ni interactions. This synergistic effect shifts the pathway from adsorbate evolution mechanism (AEM) to oxide pathway mechanism (OPM). The prepared CeOx@Ni(OH)2 achieves an overpotential of 152 mV at 10 mA cm-2 and operates continuously over 2000 h with limited performance decay. When integrated into an alkaline anion exchange membrane water electrolyzer (AEMWE), it requires 1.91 V to attain 1 A cm-2 and maintains stable operation for 450 h. This OPM activation strategy shows potential applicability across CeOx-loaded transition metal hydroxides, including Ni(OH)2, Co(OH)2, NiCo, and NiFe layered double hydroxides, offering a promising approach for alkaline OER enhancement.

alkaline water oxidation

Stimulation of neutrophil oxidative metabolism by the alternate pathway of complement activation: a mechanism for the spontaneous NBT test.

The reduction of nitroblue tetrazolium dye by human neutrophils was measured in the presence of serum in which the complement system had been activated through the alternate pathway by interaction with inulin. Neutrophils incubated with serum inulin supernatants reduced the dye and showed a general increase in oxidative metabolism. The oxidation of glucose-1-14-C by supernatant prepared from selectively depleted sera indicated that the neutrophil-stimulating factor(s) was generated through the alternate pathway of complement activation. The possibility that inulun had been ingested as a particle was ruled out by light microscopy and radiolabeling studies. The failure of neutrophils stimulated by the serum-inulun supernatants to migrate after exposure to a chemotactic agent suggested that the site of neutrophil-complement interaction was on the cell membrane. It is concluded from these results that biologically active fragments generated through the alternative pathway of complement activation can stimulate neutrophil metabolism in the absence of phagocytosis. Interaction of such fragments with circulating neutrophils in vivo and the subsequent metabolic activation of these cells is one explanation for the spontaneous reduction of nitroblue tetrazolium dye in vitro by neutrophils from patients with certain infections and inflammatory disorders.

Absorption

The metabolism of biogenic amines in experimental animals and in human subjects during acute and chronic administration of ethanol.

Ethanol has been shown to induce a shift in catecholamine metabolism peripherally from normally oxidative pathways to reductive pathways. The mechanisms of this effect may result from competitive inhibition of aldehyde dehydrogenase by acetaldehyde. The shift in metabolism cannot be found in brain and alterations in catecholamine function may reflect changes in the turnover of these amines.

Acetaldehyde

Exploring the Mechanism of Zhigancao Decoction in the Treatment of Chronic Heart Failure via Modulation of Oxidative Stress.

BACKGROUND: Zhigancao decoction has shown therapeutic potential in the management of chronic heart failure (CHF); however, the molecular mechanisms underlying its pharmacological effects remain incompletely understood. This study aimed to investigate its potential mechanisms, with a particular focus on oxidative stress-related pathways. METHODS: The chemical profile of Zhigancao decoction was characterized by LC-MS/MS, and putative targets were predicted using SwissTargetPrediction. A protein-protein interaction (PPI) network was established using the STRING database and Cytoscape software, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Differentially expressed genes from two GEO datasets (GSE9128 and GSE84796) were integrated with reactive oxygen species (ROS)-related genes to identify candidate targets. Network pharmacology and molecular docking were subsequently performed to investigate compound-target interactions. RESULTS: A total of 66 chemical constituents and 818 putative targets were characterized and collected, respectively. Among these targets, MMP9 emerged as a central candidate associated with the therapeutic effects of Zhigancao decoction. GO and KEGG enrichment analyses demonstrated that the core targets were significantly enriched in oxidative stress-related pathways, inflammatory signaling cascades, and cell fate regulatory pathways. Computational deconvolution of bulk transcriptomic data suggested marked alterations in the estimated immune cell composition of the CHF microenvironment. Network pharmacology analysis further indicated that multiple chemical constituents of Zhigancao decoction converge on MMP9 and its associated pathways. Molecular docking analysis demonstrated favorable binding affinities between 10 representative compounds and MMP9, with binding energies below -7.0 kcal/mol. CONCLUSIONS: In silico predictions suggest that Zhigancao decoction may exert potential therapeutic effects against CHF through computationally predicted targeting of MMP9 and associated oxidative stress- and immune-related pathways. These computational findings provide a theoretical foundation for future experimental investigations into the mechanisms of Zhigancao decoction in CHF, though clinical application would require confirmation through rigorous in vivo and clinical studies.

Oxidative Stress

Network pharmacology insights into the mechanistic basis of Taohe Chengqi Decoction in the treatment of constipation.

Constipation is a common gastrointestinal disorder associated with impaired motility, inflammation, and altered neuro-intestinal regulation. Taohe Chengqi Decoction, a classical prescription from Shang Han Lun, has been widely applied in the treatment of constipation, yet its pharmacological mechanisms remain insufficiently understood. We integrated systems pharmacology and network analysis to elucidate the therapeutic mechanisms of Taohe Chengqi Decoction against constipation. Active compounds and their putative targets were retrieved from traditional Chinese medicine systems pharmacology and PubChem, while constipation-related genes were collected from GeneCards and OMIM. Shared targets were identified and subsequently analyzed using STRING to construct a protein-protein interaction network. Hub proteins were ranked by degree centrality. A drug-disease-target network was built to map the interactions between Taohe Chengqi Decoction and constipation. Gene ontology and Kyoto encyclopedia of genes and genomes enrichment analyses were performed to uncover functional modules and signaling pathways. A total of 188 common targets were identified. Protein-protein interaction network analysis highlighted AKT1, interleukin-6 (IL6), IL1B, and JUN as hub proteins, suggesting central roles in regulating inflammation, apoptosis, and signal transduction. Additional nodes with high connectivity, such as caspase-3, PTGS2, signal transducer and activator of transcription 3, hypoxia-inducible factor-1α, estrogen receptor 1, and epidermal growth factor receptor, were implicated in apoptosis, oxidative stress, and transcriptional regulation. The drug-disease-target network revealed a dense and highly interconnected structure, reflecting the multicomponent, multi-target nature of Taohe Chengqi Decoction. Kyoto encyclopedia of genes and genomes enrichment indicated significant involvement of the advanced glycation end-product binding to their receptor signaling pathway, along with IL-17, TNF, and HIF-1 pathways, underscoring the contribution of inflammatory and oxidative stress-related processes. This study, based on computational pharmacology analysis, predicts that Taohe Chengqi Decoction may exert therapeutic effects on constipation through an integrated regulation involving multiple components, targets, and pathways. The potential mechanisms are likely associated with the modulation of inflammatory responses, apoptosis, and oxidative stress, with the advanced glycation end-product binding to their receptor signaling pathway possibly acting as a key mediator. These findings provide theoretical insights and future directions for elucidating the molecular mechanisms underlying the therapeutic effects of Taohe Chengqi Decoction against constipation.

Drugs, Chinese Herbal

[Mechanisms of aliphatic alcohols oxidation by enzymatic systems of the liver].

The main pathways of aliphatic alcohols oxidation in human and mammalian liver, i.e. dehydration of alcohols by cytosolic alcohol dehydrogenases and oxidation in the presence of microsomal enzymatic system, catalase and hydrogen peroxide are described. A special emphasis is laid upon the interaction of alcohols with terminal oxidase of the microsomal hydroxylating system, i.e. cytochrome P-450. The relative role of these three oxidative pathways in alcohol conversions is evaluated.

Alcohol Oxidoreductases

Specificity of isoniazid on growth inhibition and competition for an oxidized nicotinamide adenine dinucleotide regulatory site on the electron transport pathway in Mycobacterium phlei.

The mechanism of action of isoniazid (INH) on saprophytic and atypical mycobacteria is thought to be different from that on Mycobacterium tuberculosis because higher concentrations are required to be effective in these species. In this investigation, M. phlei was inhibited by INH at a concentration of 25 mug/ml. Benzoic acid hydrazide (BZH) and nicotinic acid hydrazide (NAH) were inhibitory at levels of 300 and 500 mug/ml, respectively. Inhibition by these compounds was not inoculum dependent. An isolated M. phlei mutant resistant to 100 mug of INH per ml (Inh(r)) was inhibited by INH only at concentrations about equal to those inhibitory for BZH and NAH. When NAH and BZH were below their minimal inhibitory concentrations, INH inhibition was antagonized. Hence, there appears to be a single target site for INH in mycobacteria with different affinities for various hydrazide analogs of INH. The increased inhibitory levels required for the atypical and saprophytic species are due to a decreased affinity of the target site for INH in these species. INH also inhibited both the oxidized nicotinamide adenine dinucleotide (NAD(+)) and adenosine 5'-monophosphate stimulation of reduced NAD (NADH) oxidase activity associated with the M. phlei and M. tuberculosis H(37)R(a) electron transport particles. INH did not reverse the NAD(+) stimulation of oxidase activity in the Inh(r) strain of M. phlei. No direct inhibitory effect of INH on NADH oxidase activity was observed. Incubation of M. phlei electron transport particles at 0 degrees C with INH resulted in a dramatic loss of oxidase activity which could have been prevented if NAD(+) were present. However, INH had no effect upon the NADH oxidase when stored with electron transport particles isolated from the Inh(r) strain. Therefore, INH inhibition of regulation and/or stabilization of the electron transport pathway by NAD(+) or adenosine 5'-monophosphate may account, in part, for the lethal action of the drug on mycobacteria.

Adenosine Monophosphate

Glucose metabolism in perfused skeletal muscle. Demonstration of insulin resistance in the obese Zucker rat.

1. The effect of insulin (0.5, 10 and 50 munits/ml of perfusate) on glucose uptake and disposal in skeletal muscle was studied in the isolated perfused hindquarter of obese (fa/fa) and lean (Fa/Fa) Zucker rats and Osborne-Mendel rats. 2. A concentration of 0.5 munit of insulin/ml induced a significant increase in glucose uptake (approx. 2.5 mumol/min per 30 g of muscle) in lean Zucker rats and in Osborne-Mendel rats, and 10 munits of insulin/ml caused a further increase to approx. 6 mumol/min per 30 g of muscle; but 50 munits of insulin/ml had no additional stimulatory effect. In contrast, in obese Zucker rats only 10 and 50 munits of insulin/ml had a stimulatory effect on glucose uptake, the magnitude of which was decreased by 50-70% when compared with either lean control group. Since under no experimental condition tested was an accumulation of free glucose in muscle-cell water observed, the data suggest an impairment of insulin-stimulated glucose transport across the muscle-cell membrane in obese Zucker rats. 3. The intracellular disposal of glucose in skeletal muscle of obese Zucker rats was also insulin-insensitive: even at insulin concentrations that clearly stimulated glucose uptake, no effect of insulin on lactate oxidation (nor an inhibitory effect on alanine release) was observed; [14C]glucose incorporation into skeletal-muscle lipids was stimulated by 50 munits of insulin/ml, but the rate was still only 10% of that observed in lean Zucker rats. 4. The data indicate that the skeletal muscle of obese Zucker rats is insulin-resistant with respect to both glucose-transport mechanisms and intracellular pathways of glucose metabolism, such as lactate oxidation. The excessive degree of insulin-insensitivity in skeletal muscle of obese Zucker rats may represent a causal factor in the development of the glucose intolerance in this species.

Adipose Tissue

Macrophage plasticity and metabolic control in muscle repair and disease.

Inflammation is a tightly regulated process essential for skeletal muscle repair, and its dysregulation contributes to chronic disease and impaired regeneration. Following injury, muscle repair involves a coordinated immune response initiated by neutrophil infiltration, followed by macrophage recruitment and diversification. Rather than existing as discrete subsets, macrophages span a continuum of functional states that evolve over time in response to local environmental cues, enabling transitions from clearing debris and pro-inflammatory signaling to supporting resolution of inflammation, and remodeling and regeneration of the tissue. This functional plasticity is closely linked to intracellular metabolic programs. In this review, we examine how metabolic pathways, particularly the balance between glycolysis and oxidative phosphorylation, govern macrophage behavior through epigenetic mechanisms, thereby coupling cellular metabolism to inflammatory and regenerative gene expression. We further explore how these interconnected pathways are disrupted in chronic inflammatory muscle diseases, including muscular dystrophies. Recent transcriptomic studies highlight pathogenic macrophage populations with altered metabolic and epigenetic profiles that contribute to fibrosis and impaired regeneration. By integrating findings from both acute injury and chronic disease contexts, we provide a framework to explore macrophage function through a metabolic and epigenetic lens and discuss emerging strategies aimed at restoring macrophage plasticity and promoting the resolution of inflammation in muscle disease.

Humans

Lithosyntrophy: Obligate syntrophy in a phosphite-oxidizing, methanogenic culture.

The anaerobic conversion of organic matter to methane and carbon dioxide typically relies on obligate syntrophic interactions between bacteria and methanogenic archaea, where interspecies electron transfer enables thermodynamically constrained reactions to proceed near equilibrium. Syntrophs often couple the oxidation of fermentation products such as fatty acids and alcohols to the reduction of protons to form hydrogen (H2). These reactions can only proceed if low H2 concentrations are maintained by H2-consuming syntrophic partners. Here, we describe "lithosyntrophy," a mode of syntrophic interaction in which electrons that drive hydrogenotrophic methanogenesis originate from an inorganic compound rather than from the canonical organic substrates. Candidatus Phosphitivorax anaerolimi Phox-21 oxidizes phosphite (HPO32-, oxidation state +3) to phosphate coupled to hydrogenogenesis in an obligate energetic dependency on a hydrogenotrophic methanogen, Methanoculleus sp. Physiology experiments, thermodynamic calculations, genomic annotation, and metaproteomics analysis collectively revealed a mechanism for syntrophic phosphite oxidation in Phox-21. In this pathway, electrons derived from phosphite drive H2 production via an electron-confurcating hydrogenase. Unlike previously characterized acetogenic phosphite oxidizers, Phox-21 is a mixotroph that assimilates acetate to form biomass. Lithosyntrophic phosphite oxidizers may play important roles both in transferring reducing equivalents as well as biologically available phosphorus to other members of their surrounding microbial communities, establishing a previously unrecognized metabolic and biogeochemical link between the phosphorus and carbon redox cycles in anoxic ecosystems.

Oxidation-Reduction

The fate of 14C in glucose 6-phosphate synthesized from [1-14C]Ribose 5-phosphate by enzymes of rat liver.

1. Glucose 5-phosphate was synthesized from ribose 5-phosphate by an enzyme extract prepared from an acetone-dried powder of rat liver. Three rates of ribose 5-phosphate utilization were observed during incubation for 17 h. An analysis of intermediates and products formed throughout the incubation revealed that as much as 20% of the substrate carbon could not be accounted for. 2. With [1-14C]ribose 5-phosphate as substrate, the specific radioactivity of [14C]glucose 6-phosphate formed was determined at 1, 2, 5 and 30 min and 3, 8 and 17 h. It increased rapidly to 1.9-fold the initial specific radioactivity of [1-14C]ribose 5-phosphate at 3 h and then decreased to a value approximately equal to that of the substrate at 6 h, and finally at 17 h reached a value 0.8-fold that of the initial substrate [1-14C]ribose 5-phosphate. 3. The specific radioactivity of [14C]ribose 5-phosphate decreased to approx. 50% of its inital value during the first 3 h of the incubation and thereafter remained unchanged. 4. The distribution of 14C in the six carbon atoms of [14C]glucose 6-phosphate formed from [1-14C]ribose 5-phosphate at 1, 2, 5 and 30 min and 3, 8 and 17 h was determined. The early time intervals (1--30 min) were characterized by large amounts of 14C in C-2 and in C-6 and with C-1 and C-3 being unlabelled. In contrast, the later time intervals (3--17 h) were characterized by the appearance of 14C in C-1 and C-3 and decreasing amounts of 14C in C-2 and C-6. 5. It is concluded that neither the currently accepted reaction sequence for the non-oxidative pentose phosphate pathway nor the 'defined' pentose phosphate-cycle mechanism can be reconciled with the labelling patterns observed in glucose 6-phosphate formed during the inital 3 h of the incubation.

Animals

Nrf2/Keap1/ARE regulation by plant secondary metabolites: a new horizon in brain tumor management.

Brain cancer is regarded as one of the most life-threatening forms of cancer worldwide. Oxidative stress acts to derange normal brain homeostasis, thus is involved in carcinogenesis in brain. The Nrf2/Keap1/ARE pathway is an important signaling cascade responsible for the maintenance of redox homeostasis, and regulation of anti-inflammatory and anticancer activities by multiple downstream pathways. Interestingly, Nrf2 plays a somewhat, contradictory role in cancers, including brain cancer. Nrf2 has traditionally been regarded as a tumor suppressor since its cytoprotective functions are considered to be the principle cellular defense mechanism against exogenous and endogenous insults, such as xenobiotics and oxidative stress. However, hyperactivation of the Nrf2 pathway supports the survival of normal as well as malignant cells, protecting them against oxidative stress, and therapeutic agents. Plants possess a pool of secondary metabolites with potential chemotherapeutic/chemopreventive actions. Modulation of Nrf2/ARE and downstream activities in a Keap1-dependant manner, with the aid of plant-derived secondary metabolites exhibits promise in the management of brain tumors. Current article highlights the effects of Nrf2/Keap1/ARE cascade on brain tumors, and the potential role of secondary metabolites regarding the management of the same.

Animals

Redox Regulation in Glioblastoma: Mechanisms, Biomarkers, and Therapeutic Implications.

Glioblastoma is the most aggressive primary tumor of the central nervous system, characterized by high invasiveness, rapid progression, and a poor prognosis despite the current treatment modalities. Molecular stratification, using biomarkers such as IDH1, TERT, and MGMT, is a crucial step in the 2021 WHO classification for improving diagnosis and prognosis. Oxidative stress, a feature of GB, has been identified as an important factor in the initiation, progression, and resistance to treatment. It occurs due to an imbalance between reactive oxygen species generated by mitochondrial metabolism, NADPH oxidases, and exogenous sources such as ionizing radiation and xenobiotics and antioxidant defense. This imbalance leads to DNA damage, genomic instability, and deregulation of signaling pathways involved in cell proliferation, apoptosis, and tumor progression. This review provides an overview of key oxidative stress biomarkers and their dual roles in tumor suppression and progression. It highlights how oxidative stress contributes to treatment responses and resistance to current GB treatments, including redox-adaptive mechanisms such as the Nrf2-Keap1 pathway, which promotes radioresistance. Finally, it discusses the potential of understanding these mechanisms to develop therapeutic strategies that target redox balance and homeostasis, aiming to overcome resistance and improve survival outcomes for glioblastoma patients.

Humans

Protein thiol-disulfide interchange and interfacing with biological systems.

Disulfide-containing proteins offer unique advantages for mechanistic studies of the formation of native three-dimensional structure from unordered, reduced precursors. The main advantage is that covalent intermediates are formed; by characterizing these intermediates, one obtains substantial information about the reaction pathway. Thiol-disulfide interchange is a major component of most oxidative mechanisms carrying thiol to disulfide; thus, it required some attention in its own right. Afinsen's descriptions of a "shuffle-ase" enzyme led us to examine the rates of the uncatalyzed exchange under physiologically plausible conditions. Somewhat surprisingly, we found that the rates for formation of several native proteins in uncatalyzed systems containing GSSG and GSH are as great as with the "shuffle-ase" enzyme, suggesting that a substantial portion of biological thiol oxidations proceed by uncatalyzed exchange. While thiol-disulfide exchange of course results in no net change in the oxidation level of a system, catalytic linkage of thiol or disulfide to other redox systems provides a mechanism for achieving net changes.

Chemical Phenomena

Elucidation of the immunotoxicity of PEDOT: PSS on RAW264.7 macrophages by oxidative stress, inflammatory response, and NF-κB pathway activation.

Poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) nanoparticles, widely used conductive polymers, pose environmental and health risks due to their nanoscale dispersion. However, the characteristics of PEDOT: PSS in aquatic systems and the underlying mechanisms of its toxicity in animal and cell models remain poorly understood. This study aimed to investigate the toxicological effects of PEDOT: PSS nanoparticles on macrophages, with a focus on RAW 264.7 cells. After an acute exposure to PEDOT: PSS nanoparticles at different concentrations (5, 10, 20 μg/mL), we observed significant impairments in cell viability, proliferation, migration, adhesion, and phagocytosis, as well as morphological alterations. Concurrently, there was a marked upregulation of inflammatory markers, including reactive oxygen species (ROS), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β), indicating the induction of oxidative stress and inflammation. Mechanistically, PEDOT: PSS nanoparticles activated the nuclear factor kappa B (NF-κB) signaling pathway, a key regulator of inflammatory responses, suggesting that they may mediate inflammatory responses and cell damage via activation of the NF-κB signaling pathway. These findings reveal the toxic mechanism of PEDOT: PSS nanoparticles in macrophages and provide new insights into their biological safety implications.

Animals

Preliminary Exploration on Melatonin-Mediated Protective Effects in Intracranial Aneurysms: Transcriptomic, Proteomic, and Metabolomic Profiling of Cerebral Vascular Tissues Combined with in vivo Animal Experiments.

BACKGROUND: Intracranial aneurysm (IA) is a life-threatening cerebrovascular disease with unclear molecular mechanisms and limited drug treatment. Our previous research has shown that melatonin (MLT) has potential protective effects in IA, but its mechanism remains unclear. The purpose of this study is to explore the pathological mechanism of IA and the therapeutic mechanism of MLT by integrating transcriptomic, proteomic and metabolomic analyses. METHODS: In this study, mouse models of IA were successfully established by combining elastase injection with angiotensin II infusion. C57BL/6 mice were divided into control, IA model, IA model+MLT, and IA model+nimodipine groups. The pathological conditions were evaluated by hematoxylin-eosin (HE) staining, TUNEL staining, and scanning electron microscopy. Transcriptomic (n=3 for each group), proteomic (n=3 for each group), and metabolomic (n=6 for each group) analyses were performed based on cerebral vascular tissue samples. The screening thresholds for differentially expressed genes and differentially expressed proteins were P <0.05 and fold change >1.5 and fold change <0.667. The screening criteria for differential metabolites were variable importance for the projection (VIP)> 1.0, fold change >1.2 and fold change <0.833, and P <0.05. RESULTS: MLT alleviated brain tissue damage, vascular endothelial damage, structural disruption, and apoptosis in IA mice. Transcriptomic, proteomic and metabolomic analyses identified numerous differential molecules. Functional annotation revealed that these molecules may be involved in biological pathways and processes such as immune inflammation, vascular remodeling, extracellular matrix remodeling, neuropeptide activity, oxidative stress and metabolic pathways, thereby regulating the occurrence and development of IA or mediating the therapeutic effects of MLT. Furthermore, transcriptomic and proteomic analyses also suggest that there may be extensive post-transcriptional, translational and post-translational regulatory events in the progression of IA and the therapeutic effects of MLT. Integrated transcriptomic and proteomic analyses suggest that Npy may be a key molecule in regulating IA progression and mediating MLT therapeutic effects, and its potential value is further supported by our immunohistochemical validation results. CONCLUSION: Multi-omics integrative analysis preliminarily revealed that the potential mechanisms of MLT may involve the regulation of inflammatory response, vascular remodeling, extracellular matrix remodeling, neuropeptide activity, oxidative stress, metabolic pathways, and post-transcriptional/translational regulation.

Animals

JP1 peptide modulates oxidative stress and autophagy via Keap1-Nrf2-ARE in ALS model mice.

BACKGROUND: The simultaneous modulation of oxidative stress and autophagy represents a potential therapeutic strategy for amyotrophic lateral sclerosis (ALS), yet agents capable of coordinately regulating both processes remain scarce. The Keap1&#x2011;Nrf2&#x2011;ARE pathway serves as a critical hub linking redox homeostasis and autophagic regulation, making it an attractive target for ALS intervention. JWA is a stress&#x2011;responsive protein involved in cellular protection against oxidative injury, and its neuroprotective effects have been shown to depend on activation of the MEK/ERK&#x2011;Nrf2 axis. JP1 is a functional oligopeptide derived from the JWA protein that has been engineered to cross the blood-brain barrier and specifically target integrin &#x3b1;V&#x3b2;3. Based on the link between JWA and Nrf2 signaling, we hypothesized that JP1 activates the Keap1&#x2011;Nrf2&#x2011;ARE pathway to coordinate antioxidant defense and autophagic clearance. Here, we evaluated this hypothesis in the SOD1&#x2011;G93A mouse model, a well&#x2011;established transgenic model of familial ALS, and elucidated the underlying mechanisms. METHODS: We evaluated the efficacy of JP1 in the SOD1-G93A mice model using behavioral phenotyping and survival analysis. The coordinated mechanism was investigated in spinal cord tissues by profiling the Keap1-Nrf2-ARE pathway and oxidative stress, quantifying autophagic flux (by Western blotting and transmission electron microscopy) and neuronal apoptosis, and evaluating histology (by Nissl staining and immunofluorescence). Integrated transcriptomic and proteomic analyses further elucidated the global molecular landscape underlying the therapeutic effects of JP1. RESULTS: JP1 treatment ameliorated motor deficits and extended survival in SOD1-G93A mice without adversely affecting liver or kidney function. JP1 crossed the blood-brain barrier, targeted motor neurons expressing integrin &#x3b1;V&#x3b2;3, and activated the ERK pathway. This promoted Keap1/Cul3 degradation and Nrf2 nuclear translocation, thereby activating the Keap1-Nrf2-ARE pathway to alleviate oxidative stress. Concurrently, JP1 restored autophagic flux, increased autophagic activity, attenuated motor neuron injury, suppressed neuronal apoptosis, and preserved neuronal structural integrity. The Nrf2 inhibitor ML385 reversed the protective effects of JP1 on survival, motor function, autophagy, oxidative stress, and neuronal apoptosis, which confirms that JP1 acts via the Nrf2 pathway. CONCLUSIONS: JP1 acts as a promising coordinator of antioxidant and autophagic processes by targeting the Keap1-Nrf2-ARE pathway, thus highlighting its therapeutic potential for ALS.

Animals