Efficient Reactive Oxygen Species Scavenging Research Articles

Novel biomimetic macromolecules system for highly efficient lubrication, ROS scavenging and osteoarthritis treatment

The early stages of osteoarthritis (OA) in the joints are typically characterized by two key factors: the dysfunction of articular cartilage lubrication and inflammation resulting from the excessive production of reactive oxygen species (ROS). Synthetic injectable macromolecular materials present great potential for preventing the progression of early OA. In this study, to mimic the excellent lubricity of brush-like aggregates found in natural synovial fluid, we develop a novel macromolecular biolubricant (CS-PS-DA) by integrating adhesion and hydration groups onto backbone of natural biomacromolecules. CS-PS-DA exhibits a strong affinity for cartilage surfaces, enabling the formation of a stable lubrication layer at the sliding interface of degraded cartilages to restore joint lubrication performance. In vitro results from ROS scavenging and anti-inflammatory experiments indicate the great advantage of CS-PS-DA to decrease the levels of proinflammatory cytokines by inhibiting ROS overproduction. Finally, in vivo rats OA model demonstrates that intra-cavitary injection of CS-PS-DA could effectively resist cartilage wear and mitigated inflammation in the joints. This novel biolubricant provides a new and timely strategy for the treatment of OA.

Yungas propolis in the scavenging of vitamin B2-photogenerated ROS

This study focused on the scavenging action and antioxidant activity of propolis from Trancas (ProTr) as a promoter and scavenger of Riboflavin (Rf)-photogenerated reactive oxygen species (ROS), widely used in traditional medicine as an antioxidant. A thorough examination of the antioxidant activity of ethanolic extract (EE) was made possible by a kinetic and mechanistic study of the total polyphenol contents in the extract using stationary photolysis and time-resolved photochemical methods.Under aerobic visible-light-irradiation conditions, with Rf as the only light-absorber molecule, a complex frame of competitive interactions takes place, with the triplet excited states of Rf being quenched by ProTr. Rf triplet excited states can interact with ProTr or produce singlet oxygen and superoxide radical anions. The results indicated ProTr to be an efficient ROS scavenger. The antioxidant behavior of ProTr is similar to that of Trolox, a well-known antioxidant. Propolis is slightly photodegraded by interaction with the mentioned ROS, highlighting the crucial role of ProTr and its potential in mitigating oxidative stress-induced damage in biological systems. These findings suggest that ProTr could be a promising natural alternative to synthetic antioxidants for combating oxidative stress.

Inhibiting advanced glycation end products (AGEs) of high-performance hemodialysis membranes self-assembled by gallic acid and Ti3C2Tx MXene

Current patients with chronic kidney disease (CKD) suffer from either accumulation of advanced glycation end products (AGEs) or inefficient clearance of the middle molecule uremic toxins, threatening their long-term survival rate. In particular, conventional hemodialysis membranes cannot prevent AGEs formation because of continuous oxidative stress from reactive oxygen species (ROS). Herein, a persistent ROS scavenging and efficient uremic toxin clearance of hemodialysis membrane is proposed by the in situ deposition of a gallic acid-Ti3C2Tx MXene (GA-MXene)n multilayers through a self-assembly method, where n denotes the number of deposition layers. These hemodialysis membranes have a highly interconnecting composite laminate with tunable pore size. In the dialysis experiment, the (GA-MXene)2 membrane with the vertical nano-slits shows the highest middle molecule uremic toxin clearance of 80.0% compared with state-of-the-art hemodialysis membranes, which has been approximately equal to the clearance of small molecule urea. Furthermore, GA conferring efficient ROS scavenging rate over dialysis treatment time allows anti-oxidative activities to inhibit AGEs’ formation. (GA-MXene)n multilayers enhanced the serum total antioxidant capacity and suppressed lipid peroxidation from oxidative damage. Ultimately, the (GA-MXene)n hemodialysis membranes provide excellent anticoagulant properties and cytocompatibility through the heparin-mimicking sulfonated Ti3C2Tx MXene and biological activity of GA. This work facilitates the blood purification application of MXenes and opens up an avenue for developing functional multilayers for high-performance hemodialysis membranes and beyond.

Superoxide dismutase mimetic nanozymes attenuate cardiac microvascular ischemia–reperfusion injury associated with hyperhomocysteinemia

The combination of homocysteine (Hcy) and copper ion (Cu2+) induces cardiac microvascular ischemia–reperfusion injury (IRI) by causing oxidative stress in the reperfusion treatment of ischemic cardiopathy. Therefore, antioxidant elimination of reactive oxygen species (ROS) shows great potential in the treatment of IRI. Herein, cerium vanadate nanorods (CVNRs) were designed and developed as an efficient ROS scavenger for the treatment of myocardial IRI in hyperhomocysteinemic rat (HHcyR) model. Thanks to its outstanding superoxide dismutase (SOD)-like activity, the CVNRs showed a significant antioxidant effect in human cardiac microvascular endothelial cells treated with Hcy and Cu2+ under hypoxia/reperfusion condition and greatly preserved the morphology and function of mitochondria. Further intravenous administration of CVNRs significantly maintained the integrity and perfusion of microvasculature, minimized the microcirculation malfunction, and finally reduced the myocardial infarction and maintained the heart function after IRI. Moreover, the administration of CVNRs in HHcyR exhibited negligible organ toxicity and inflammation response, indicating their excellent biocompatibility and biosafety. Collectively, the SOD-mimicking CVNRs can serve as a promising antioxidant nanozyme to treat cardiac microvascular IRI complicated with hyperhomocysteinemia, providing a new prospect for the development of antioxidant nanozyme in IRI treatment even with other risk factors.

New Prospects for Improving Microspore Embryogenesis Induction in Highly Recalcitrant Winter Wheat Lines

Among various methods stimulating biological progress, double haploid (DH) technology, which utilizes the process of microspore embryogenesis (ME), is potentially the most effective. However, the process depends on complex interactions between many genetic, physiological and environmental variables, and in many cases, e.g., winter wheat, does not operate with the efficiency required for commercial use. Stress associated with low-temperature treatment, isolation and transfer to in vitro culture has been shown to disturb redox homeostasis and generate relatively high levels of reactive oxygen species (ROS), affecting microspore vitality. The aim of this study was to investigate whether controlled plant growth, specific tiller pre-treatment and culture conditions could improve the potential of microspores to cope with stress and effectively induce ME. To understand the mechanism of the stress response, hydrogen peroxide levels, total activity and the content of the most important low-molecular-weight antioxidants (glutathione and ascorbate), as well as the content of selected macro- (Mg, Ca, NA, K) and micronutrients (Mn, Zn, Fe, Cu, Mo) were determined. These analyses, combined with the cytological characteristics of the microspore suspensions, allowed us to demonstrate that an increased microspore vitality and stronger response to ME induction were associated with higher stress resistance based on more efficient ROS scavenging and nutrient management. It was shown that a modified procedure, combining a low temperature with mannitol and sodium selenate tiller pre-treatment, reduced oxidative stress and improved the effectiveness of ME in winter wheat lines.

Antioxidative bioactive glass reinforced injectable hydrogel with reactive oxygen species scavenging capacity for diabetic wounds treatment

Diabetic wound healing remains a critical challenge due to its special hyperglycemic environment and disorder in wound healing process. The hyperglycemic microenvironment of diabetic wounds causes inhibitive angiogenesis and overproduction of reactive oxygen species (ROS), which leads to oxidative stress damage to biological macromolecules and cells, and hindrance of wound healing. Herein, an injectable thermo-sensitive methyl cellulose hydrogel with capacities of improving angiogenesis, scavenging ROS and antibiosis is developed to overcome the obstacles of diabetic wound healing. Through loading antioxidative cerium-doped bioactive glass nanoparticles (CeBG), the hydrogel demonstrates efficient ROS scavenging to protect cells from oxidative stress harm, as well as stimulation of dermal fibroblast proliferation and migration. Moreover, addition of quaternary chitosan (QCS) endows the hydrogel with antibacterial ability against E. coli and S. aureus. The hydrogel effectively accelerates diabetic wound healing in a mice model, and more importantly, the wound area presents improved angiogenesis, diminished inflammation and decreased ROS level. These data demonstrate that the hydrogel is a promising biomaterial for the clinical treatment of diabetic wounds, as well as facilitating the therapy of oxidative stress related diseases.

Pt-Clusters-Equipped Antioxidase-Like Biocatalysts as Efficient ROS Scavengers for Treating Periodontitis.

Developing high-efficiency artificial biocatalysts for scavenging reactive oxygen species (ROS) is critical for treating inflammation diseases and promoting tissue regeneration. By mimicking the active sites in catalase, here, a Pt-clusters-equipped antioxidase-like biocatalysts (Pt─CN) with superior catalytic abilities for stem cell protection and periodontitis treatment are reported. Owing to the excellent effects of multiple Pt clusters, Pt─CN yields exceptional catalytic ROS-scavenging activities for multiple types of ROS. In vitro studies show that Pt─CN can effectively protect stem cell survival, adhesion, and differentiation in a high ROS levels microenvironment. Additionally, Pt─CN can reduce the M1/M2 ratio of macrophages when stimulated by lipopolysaccharide. In vivo treatment of mouse periodontitis further confirms the protection against bone loss and reduction in the inflammatory response. This study provides a basis for the application of biocatalysts with Pt catalytic center in macrophage polarization, stem cell protection, and periodontitis treatment, thus offering a new strategy for the design of high-performance artificial biocatalysts.

An Immunomodulatory Hydrogel by Hyperthermia-Assisted Self-Cascade Glucose Depletion and ROS Scavenging for Diabetic Foot Ulcer Wound Therapeutics.

Current therapeutic protocols for diabetic foot ulcers (DFUs), a severe and rapidly growing chronic complication in diabetic patients, remain nonspecific. Hyperglycemia-caused inflammation and excessive reactive oxygen species (ROS) are common obstacles encountered in DFU wound healing, often leading to impaired recovery. These two effects reinforce each other, forming an endless loop. However, adequate and inclusive methods are still lacking to target these two aspects and break the vicious cycle. This study proposes a novel approach for treating DFU wounds, utilizing an immunomodulatory hydrogel to achieve self-cascade glucose depletion and ROS scavenging to regulate the diabetic microenvironment. Specifically, AuPt@melanin-incorporated (GHM3) hydrogel dressing is developed to facilitate efficient hyperthermia-enhanced local glucose depletion and ROS scavenging. Mechanistically, in vitro/vivo experiments and RNA sequencing analysis demonstrate that GHM3 disrupts the ROS-inflammation cascade cycle and downregulates the ratio of M1/M2 macrophages, consequently improving the therapeutic outcomes for dorsal skin and DFU wounds in diabetic rats. In conclusion, this proposed approach offers a facile, safe, and highly efficient treatment modality for DFUs.

Computational and experimental analysis of foxtail millet under salt stress and selenium supplementation.

Salinity stress is a major threat to crop growth and productivity. Millets are stress-tolerant crops that can withstand the environmental constraints. Foxtail millet is widely recognized as a drought and salinity-tolerant crop owing to its efficient ROS scavenging mechanism. Ascorbate peroxidase (APX) is one of the reactive oxygen species (ROS) scavenging enzymes that leads to hydrogen peroxide (H2O2) detoxification and stabilization of the internal biochemical state of the cell under stress. This inherent capacity of the APX enzyme can further be enhanced by the application of an external mitigant. This study focuses on the impact of salt (NaCl) and selenium (Se) application on the APX enzyme activity of foxtail millet using in silico and in-vitro techniques and mRNA expression studies. The NaCl was applied in the concentrations, i.e., 150mM and 200mM, while the Se was applied in 1μM, 5μM, and 10μM concentrations. The in silico studies involved three-dimensional structure modeling and molecular docking. The in vitro studies comprised the morphological and biochemical parameters, alongside mRNA expression studies in foxtail millet under NaCl stress and Se applications. The in silico studies revealed that the APX enzyme showed better interaction with Se as compared to NaCl, thus suggesting the enzyme-modulating role of Se. The morphological and biochemical analysis indicated that Se alleviated the NaCl (150mM and 200mM) and induced symptoms at 1µM as compared to 5 and 10µM by enhancing the morphological parameters, upregulating the gene expression and enzyme activity of APX, and ultimately reducing the H2O2 content significantly. The transcriptomic studies confirmed the upregulation of chloroplastic APX in response to salt stress and selenium supplementation. Hence, it can be concluded that Se as a mitigant at lower concentrations can alleviate NaCl stress in foxtail millet.

An Extracellular Vesicle-Cloaked Multifaceted Biocatalyst for Ultrasound-Augmented Tendon Matrix Reconstruction and Immune Microenvironment Regulation.

The healing of tendon injury is often hindered by peritendinous adhesion and poor regeneration caused by the accumulation of reactive oxygen species (ROS), development of inflammatory responses, and the deposition of type-III collagen. Herein, an extracellular vesicles (EVs)-cloaked enzymatic nanohybrid (ENEV) was constructed to serve as a multifaceted biocatalyst for ultrasound (US)-augmented tendon matrix reconstruction and immune microenvironment regulation. The ENEV-based biocatalyst exhibits integrated merits for treating tendon injury, including the efficient catalase-mimetic scavenging of ROS in the injured tissue, sustainable release of Zn2+ ions, cellular uptake augmented by US, and immunoregulation induced by EVs. Our study suggests that ENEVs can promote tenocyte proliferation and type-I collagen synthesis at an early stage by protecting tenocytes from ROS attack. The ENEVs also prompted efficient immune regulation, as the polarization of macrophages (Mφ) was reversed from M1φ to M2φ. In a rat Achilles tendon defect model, the ENEVs combined with US treatment significantly promoted functional recovery and matrix reconstruction, restored tendon morphology, suppressed intratendinous scarring, and inhibited peritendinous adhesion. Overall, this study offers an efficient nanomedicine for US-augmented tendon regeneration with improved healing outcomes and provides an alternative strategy to design multifaceted artificial biocatalysts for synergetic tissue regenerative therapies.

Transferrin-Targeted Iridium Nanoagglomerates with Multi-Enzyme Activities for Cerebral Ischemia-Reperfusion Injury Therapy.

Cerebral ischemia-reperfusion injury (CIRI) is a complex pathological condition with high mortality. In particular, reperfusion can stimulate overproduction of reactive oxygen species (ROS) and activation of inflammation, causing severe secondary injuries to the brain. Despite tremendous efforts, it remains urgent to rationally design antioxidative agents with straightforward and efficient ROS scavenging capability. Herein, a potent antioxidative agent was explored based on iridium oxide nano-agglomerates (Tf-IrO2 NAs) via the facile transferrin (Tf)-templated biomineralization approach, and innovatively applied to treat CIRI. Containing some small-size IrO2 aggregates, these NAs possess intrinsic hydroxyl radicals (•OH)-scavenging ability and multifarious enzyme activities, such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx). Moreover, they also showed improved blood-brain barrier (BBB) penetration and enhanced accumulation in the ischemic brain via Tf receptor-mediated transcytosis. Therefore, Tf-IrO2 NAs achieved robust in vitro anti-inflammatory and cytoprotection effects against oxidative stress. Importantly, mice were effectively protected against CIRI by enhanced ROS scavenging activity in vivo, and the therapeutic mechanism was systematically verified. These findings broaden the idea of expanding Ir-based NAs as potent antioxidative agents to treat CIRI and other ROS-mediated diseases. STATEMENT OF SIGNIFICANCE: : (1) The ROS-scavenging activities of IrO2 are demonstrated comprehensively, which enriched the family of nano-antioxidants. (2) The engineering Tf-IrO2 nano-agglomerates present unique multifarious enzyme activities and simultaneous transferrin targeting and BBB crossing ability for cerebral ischemia-reperfusion injury therapy. (3) This work may open an avenue to enable the use of IrO2 to alleviate ROS-mediated inflammatory and brain injury diseases.

Antioxidant Chimeric Molecules: Are Chemical Motifs Additive? The Case of a Selenium-Based Ligand.

We set up an in silico experiment and designed a chimeric compound integrating molecular features from different efficient ROS (Reactive Oxygen Species) scavengers, with the purpose of investigating potential relationships between molecular structure and antioxidant activity. Furthermore, a selenium centre was inserted due to its known capacity to reduce hydroperoxides, acting as a molecular mimic of glutathione peroxidase; finally, since this organoselenide is a precursor of a N-heterocyclic carbene ligand, its Au(I) carbene complex was designed and examined. A validated protocol based on DFT (Density Functional Theory) was employed to investigate the radical scavenging activity of available sites on the organoselenide precursor ((SMD)-M06-2X/6-311+G(d,p)//M06-2X/6-31G(d)), as well as on the organometallic complex ((SMD)-M06-2X/SDD (Au), 6-311+G(d,p)//ZORA-BLYP-D3(BJ)/TZ2P), considering HAT (Hydrogen Atom Transfer) and RAF (Radical Adduct Formation) regarding five different radicals. The results of this case study suggest that the antioxidant potential of chemical motifs should not be considered as an additive property when designing a chimeric compound, but rather that the relevance of a molecular topology is derived from a chemical motif combined with an opportune chemical space of the molecule. Thus, the direct contributions of single functional groups which are generally thought of as antioxidants per se do not guarantee the efficient radical scavenging potential of a molecular species.

Ultrasmall Coordination Polymer Nanodots Fe‐Quer Nanozymes for Preventing and Delaying the Development and Progression of Diabetic Retinopathy

AbstractDiabetic retinopathy (DR) is the most prevalent type of retinal vasculopathy and the most widespread cause of preventable blindness in adults. Excessive increases in reactive oxygen species (ROS) and vascular endothelial growth factor are major initiators and drivers of DR progression, respectively. However, current DR treatment options remain limited, particularly for early DR. Nanotechnology‐mediated antioxidant strategies are gaining increasing popularity to treat ocular diseases. Quercetin has excellent ROS scavenging efficiency but poor stability and low bioavailability in physiological environments. In this study, ultrasmall Fe‐Quer nanozymes (NZs) formed by coupling quercetin with low‐toxic iron ions are reported that can mimic the activities of three important antioxidant enzymes, superoxide dismutase, catalase, and peroxidase, thereby exhibiting excellent water dispersion and efficient ROS scavenging ability. In vitro and in vivo assays validate the effects of Fe‐Quer NZs against inflammation, oxidative stress damage, microvascular leakage, and angiogenesis, particularly their vascular protective effect in early DR. Transcriptomic analysis further reveals a potential multitarget‐specific therapeutic mechanism of Fe‐Quer NZs against DR. These observations open avenues for Fe‐Quer NZs, composed of molecules of a natural product and metal ions with artificial NZ activity, as microvascular protective agents for DR and other ROS‐related diseases.

Ion exclusion, osmoregulation and management of oxidative stress improve salt tolerance in rice at seedling stage

Excess ion accumulation disturbs ionic homeostasis, creates an osmotic imbalance, and generates oxidative stress in plants under salinity stress. In the present experiment, the effect of salt stress at the seedling stage on the osmotic equilibrium and ROS scavenging potential was evaluated in ten differentially salt-sensitive rice genotypes. For this, the plants were grown hydroponically and salt stress equivalent to 12 dS m-1 was imposed at 3-4 leaf stages. The results showed that a few genotypes like FL478, AC41585, and AC39416A were able to maintain a lower Na+/K+ ratio in the leaf and thus proved more tolerant to salt stress than others. Additionally, these genotypes produced greater organic osmolytes (proline, glycine betaine, trehalose) and also had higher activities of key antioxidant enzymes (superoxide dismutase, catalase, peroxidase). On the contrary, Rashpanjor and CSR27 showed lesser ionic discrimination (higher leaf Na+/K+ ratio) but a moderate degree of salt tolerance, perhaps using Na+ effectively as an inorganic osmoticum to overcome stress. The susceptible genotypes like IR29 and Sabita were found extremely poor in restricting the upward movement of Na+, as well as the management of oxidative stress under saline conditions. From this study, we conclude that an efficient reactive oxygen species scavenging system along with greater osmotolerance helps to render salt tolerance at the seedling stage in rice.

Design of a new self-assembling antioxidant nanomedicine to ameliorate oxidative stress in zebrafish embryos.

Oxidative stress, which is a persistent state of elevated reactive oxygen species (ROS), is implicated in the pathogeneses of several diseases, making antioxidant-based therapeutics the aptest intervention. Nevertheless, the clinical failure of conventional low-molecular-weight (LMW) antioxidants in oxidative stress-related diseases to yield favorable therapeutic outcomes and an increased mortality rate attributable to their poor pharmacokinetic characteristics, necessitates the development of alternative therapeutics. In light of this, we designed and synthesized a new amphiphilic polymer functionalized with a clinically safe base polymer of poly(styrene-co-maleic anhydride) copolymer conjugated with the LMW pleiotropic antioxidant TEMPO (a potent antioxidant) and biocompatible poly(ethylene glycol) (TEMPO-installed PSMA-g-PEG), which self-assembles into nano-sized micelles (SMAPoTN) under physiological conditions. We investigated its safety and antioxidant ability using zebrafish models. Common LMW antioxidants, such as 4-hydroxy-TEMPO (TEMPOL), vitamin C, N-acetyl-L-cysteine, and edaravone exposure induced phenotypic distortions, a manifestation of developmental toxicity, and resulted in high lethality in zebrafish larvae. LMW TEMPOL also adversely affected embryo hatchability, induced arrhythmia and cardiac edema, and failed to protect against oxidative stress. In contrast, exposure of zebrafish embryos to SMAPoTN increased the hatchability, protected embryos against various inducers of oxidative stress, and did not induce any phenotypic alterations or discernible toxicity. Taken together, we conclude that SMAPoTN surpasses LMW TEMPOL in terms of the ability to protect zebrafish, attributable to efficient ROS scavenging without perturbing normal redox homeostasis. These results imply that SMAPoTN can be used as a therapeutic intervention against various oxidative stress-induced diseases. STATEMENT OF SIGNIFICANCE: Failure of low molecular weight (LMW) antioxidants to improve therapeutic index in various oxidative stress-related pathogenesis, attributable to their poor pharmacokinetic characteristics, greatly limits their clinical translation. To overcome this limitation, we developed a self-assembling antioxidant nanoparticle (SMAPoTN) comprised of amphiphilic polymer; poly(styrene-co-maleic anhydride) conjugated with TEMPO as an antioxidant and biocompatible poly(ethylene glycol). Preliminary studies carried out in the in vivo models of zebrafish embryos confirmed that exposure of LMW antioxidant resulted in acute developmental toxicity, high lethality, and failure to rescue embryos against oxidative stress inducers. In contrast, SMAPoTN did not exert discernible toxicity and significantly improved their survival under oxidative stress. Our finding establishes antioxidant nanoparticles as more suitable therapeutic intervention for oxidative stress-induced diseases than LMW antioxidants.

Bimetallic Metal–Organic Framework for Mitigating Aseptic Osteolysis

The disability rate of joint diseases can be reduced by the use of artificial joints, but joint loosening at a late state limits the lifespan and surgical efficacy of the joints. Wear particles can be recognized by macrophages and induce cells to produce reactive oxygen species (ROS) and inflammatory factors, causing persistent inflammation and decreased osteogenic activity, which ultimately leads to loosening of joint prostheses. Here, the platinum (Pt) nanozymes with excellent ROS scavenging and anti-inflammatory capabilities were encapsulated in zinc imidazolium zeolite framework-8 (ZIF-8), and then the osteogenic active element lanthanum (La) was introduced through ion exchange to finally construct a bimetallic metal-organic framework (Pt@ZIF-8@La). In vitro and in vivo experiments demonstrated that this multifunctional nanoplatform possessed the functions of efficient scavenging of ROS, immune regulation, and promotion of osteogenic differentiation. Meanwhile, the mechanism is explored that Pt@ZIF-8@La can also promote osteogenic mineralization by upregulating the ratio of the osteoprotegerin (OPG)/receptor activator of the NF-κB ligand (RANKL), which can achieve a synergistic therapeutic effect of immunomodulation and osteogenesis, thereby realizing the purpose of relieving aseptic osteolysis.

Orally administered titanium carbide nanosheets as anti-inflammatory therapy for colitis.

Rationale: Oxidative stress, resulting from excessive reactive oxygen species (ROS), plays an important role in the initiation and progression of inflammatory bowel disease (IBD). Therefore, developing novel strategies to target the disease location and treat inflammation is urgently needed.Methods: Herein, we designed and developed a novel and effective antioxidant orally-administered nanoplatform based on simulated gastric fluid (SGF)-stabilized titanium carbide MXene nanosheets (Ti3C2 NSs) with excellent biosafety and multiple ROS-scavenging abilities for IBD therapy.Results: This broad-spectrum and efficient ROS scavenging performance was mainly relied on the strong reducibility of Ti-C bound. Intracellular ROS levels confirmed that Ti3C2 NSs could efficiently eliminate excess ROS against oxidative stress-induced cell damage. Following oral administration, negatively-charged Ti3C2 NSs specifically adsorbed onto the positively-charged inflamed colon tissue via electrostatic interaction, leading to efficient therapy of dextran sulfate sodium salt (DSS)-induced colitis. The therapeutic mechanism mainly attributed to decreased ROS levels and pro-inflammatory cytokine secretion, and increased M2-phenotype macrophage infiltration and anti-inflammatory cytokine secretion, efficiently inhibiting inflammation and alleviating colitis symptoms. Due to their excellent ROS-scavenging performance, Ti3C2-based woundplast also promoted skin wound healing and functional vessel formation.Conclusions: Our study introduces redox-mediated antioxidant MXene nanoplatform as a novel type of orally administered nanoagents for treating IBD and other inflammatory diseases of the digestive tract.

A C2H2-Type Zinc-Finger Protein from Millettia pinnata, MpZFP1, Enhances Salt Tolerance in Transgenic Arabidopsis.

C2H2 zinc finger proteins (ZFPs) play important roles in plant development and response to abiotic stresses, and have been studied extensively. However, there are few studies on ZFPs in mangroves and mangrove associates, which represent a unique plant community with robust stress tolerance. MpZFP1, which is highly induced by salt stress in the mangrove associate Millettia pinnata, was cloned and functionally characterized in this study. MpZFP1 protein contains two zinc finger domains with conserved QALGGH motifs and targets to the nucleus. The heterologous expression of MpZFP1 in Arabidopsis increased the seeds’ germination rate, seedling survival rate, and biomass accumulation under salt stress. The transgenic plants also increased the expression of stress-responsive genes, including RD22 and RD29A, and reduced the accumulation of reactive oxygen species (ROS). These results indicate that MpZFP1 is a positive regulator of plant responses to salt stress due to its activation of gene expression and efficient scavenging of ROS.

Effect of cell-permeable grouper Manganese Superoxide Dismutase on environmental stress in fish

Nitrite levels are generally high in high-density aquaculture. Nitrite is a potential stress-inducing factor and can cause oxidative stress because excessive reactive oxygen species (ROS) formation through nitrite induction cannot be scavenged by the endogenous antioxidant system, thus leading to cell damage or death. Manganese Superoxide Dismutase (MnSOD) is a highly efficient endogenous ROS scavenger that quenches mitochondrial ROS and protective against oxidative stress. To enhance the efficiency of MnSOD in removing ROS and reducing oxidative caused by nitrite, in this study, we cloned grouper MnSOD (gMnSOD) fused with a cell-penetrating peptide, TAT, to construct a TAT-gMnSOD fusion protein and assessed its potential to eliminate excess ROS induced by high nitrite concentrations and enhance the resistance of zebrafish to environmental stressors. Our results revealed that TAT-gMnSOD penetrated the grouper fin (GF-1) cells, scavenged nitrite-induced intracellular ROS, and enhanced cell viability on NaNO2 treatment. Furthermore, pretreatment of zebrafish with TAT-gMnSOD fusion protein reduced the MDA content and increased the survival rate. In addition, the TAT-gMnSOD fusion protein reduced 2-phenoxyethanol toxicity and attenuated excessive anesthesia among zebrafish. In conlusion, our cell-permeable TAT-gMnSOD fusion protein effectively counters oxidative stress, prevents environmental stress-induced damage, and increases aquaculture benefits.

Porous selenium nanozymes targeted scavenging ROS synchronize therapy local inflammation and sepsis injury

Excessive reactive oxygen species (ROS) is the main factor leading to high mortality in local inflammation and sepsis. Therefore, developing efficient ROS scavenger in pro-inflammatory immune cells is an urgent strategy for therapy local inflammatory and sepsis injury. Herein, we constructed a novel mesoporous selenium-hyaluronic acid nanoenzyme therapeutic system (MSe-HA NPs) for therapy local inflammatory and sepsis injury by targeting eliminate ROS in inflammatory macrophage. In detail manners, the high specific surface area of mesoporous selenium nanoenzyme exhibited ultra-high activity like glutathione peroxidase (GPx), which catalytic speed of H2O2 scavenging was increasing to 2.02 times compare with solid Se NPs. Moreover, the broad spectrum of ROS eliminating capacity further promoted ability of MSe NPs in eliminating various ROS. More interestingly, we found that choose HA as the modification not only endowed the MSe NPs targeting to inflammatory macrophage, but the ROS degradable property of HA could enhance the MSe NPs to eliminating ROS. In vivo, MSe-HA NPs after injection showed that simultaneously cured the local inflammation and sepsis induced with LPS by quickly eliminating excessive ROS. Especially in sepsis mouse models, the survival rate and the organic dysfunction significantly improved after treated with MSe-HA NPs. Thus, this novel mesoporous nanozyme provides an effective strategy for the design of nanomedicine and the treatment of inflammation-related diseases.