Kinds Of Reactive Oxygen Species Research Articles

Differential regulation of radio-sensitivity/macrophage polarization in intestinal tissues and colorectal cancer for the optimized preoperative radiotherapy

Surgery is the preferred treatment for colorectal cancer, and the preoperative radiotherapy (pre-RT) improves surgical success and postoperative quality of life for patients. However, the therapeutic effect of pre-RT is limited by radiation resistance of tumor and radiation susceptibility of intestine, probably resulting in poor tumor suppression and postoperative anastomotic injury. Herein, we select carboxymethyl chitosan (CMCS) to complex with cerium oxide (CeO2) and calcium ion (Ca2+), obtaining CMCS/CeO2&Ca nano-enema for the optimized pre-RT of colorectal cancer. CMCS/CeO2 and CMCS/CeO2&Ca can mop up various kinds of reactive oxygen species (ROS) and decomposes H2O2 that largely exists in tumor tissue into OH and oxygen (some OH in acidic environment and main oxygen in neutral environment), enhancing free radical clearance in normal tissues and radiation sensitivity of tumor. Meanwhile, RT-induced M1 macrophage in intestinal tissue and the proportion of M2 macrophages in X-rays-treated tumor could be reduced, owing to CMCS/CeO2&Ca-induced change of ROS level. Moreover, CMCS/CeO2&Ca could also promote the proliferation of stem cells in intestine. Therefore, CMCS/CeO2&Ca improves the radio-immunotherapy outcome of colorectal cancer and reduces RT-induced intestinal inflammation/fibrosis, providing an optimal scheme and an effective enema for pre-RT for colorectal cancer.

Perspectives on the highly selective oxidation of copper-mediated C3N4-BiVO4 organic-inorganic hybrid catalysts and the efficient generation of reactive oxygen species

Singlet oxygen (1O2) is a kind of reactive oxygen species (ROS) with both oxidizability and selectivity. The construction of 1O2 is the key to improve the selectivity of various organic reactions. In this study, Cu/C3N4-BiVO4 (CCN-BVO) ternary system significantly improved the catalytic effect of selective oxidation of glycerol to prepare high value chemical dihydroxyacetone (DHA). At the same time, CCN-BVO also has a strong environmental catalytic effect, and the decomposition effect of liquid phase organic pollutants can reach more than 90 % within 2 h. The superior ROS production capacity of CCN-BVO, particularly its ability to produce 1O2, has been confirmed by electron spin resonance (ESR) and quenching experiments as the reason for its excellent catalytic effect. Electrochemical characterization and X-ray photoelectron spectroscopy (XPS) proved that Cu can be used as an intermediary to accelerate electron conduction, and can also effectively construct defects to improve oxygen absorption efficiency, thus effectively increasing ROS yield. This study also theoretically confirmed the reaction path of glycerol catalysis through DFT calculation, which provided a theoretical basis for the subsequent design of efficient catalytic materials.

Near-Infrared Fluorescence Probe for Indication of the Pathological Stages of Wound Healing Process and Its Clinical Application.

Chronic wound healing is one of the most complicated biological processes in human life, which is also a serious challenge for human health. During the healing process, multiple biological pathways are activated, and various kinds of reactive oxygen species participate in this process. Hydrogen peroxide (H2O2) involves in chronic wounds and its concentration is fluctuated in different pathological stages during the wound healing process. Therefore, H2O2 may be recognized as a powerful biomarker to indicate the wound healing process. However, the pathological roles of H2O2 cannot be fully understood yet. Herein, we proposed a near-infrared fluorescent probe DCM-H2O2 for highly sensitive and rapid detection of H2O2 in living cells and scald and incision wound mice models. DCM-H2O2 exhibited a low detection limit and high specificity with low cytotoxicity for H2O2, which had great potential for its application in vivo. The probe was successfully utilized to monitor the fluctuation of endogenous H2O2 in the proliferation process of human immortalized epidermal (HACAT) cells, which confirmed that H2O2 participated in the cells' proliferation activity through a growth factor signaling pathway. In the scald and incision wound mice models, H2O2 concentration fluctuations at different pathological stages during the wound healing process could be obtained by in vivo fluorescence imaging. Finally, H2O2 concentrations in different stages of human diabetic foot tissues were also confirmed by the proposed probe. We expect that H2O2 could be a sensitive biomarker to indicate the wound healing process.

Porous reticular Co@Fe metal-organic gel: dual-function simulated peroxidase nanozyme for both colorimetric sensing and antibacterial applications.

Constructing metal-organic gels (MOGs) with enzyme-catalyzed activity and studying their catalytic mechanism are crucial for the development of novel nanozyme materials. In this study, a Co@Fe MOG with excellent peroxidase activity was developed by a simple and mild one-pot process. The results showed that the material exhibited almost a single peroxidase activity under optimal pH conditions, which allowed it to attract and oxidize the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB). Based on the active electron transfer between the metal centers and the organic ligand in the synthetic material, the Co@Fe MOG-H2O2-TMB system was verified to be able to detect H2O2 and citric acid (CA). The catalytic microenvironment formed by the adsorption and the catalytic center accelerated the electron-transfer rate, which expedited the generation of hydroxyl radicals (˙OH, a kind of reactive oxygen species (ROS)) in the presence of H2O2. The persistence and high intensity of ˙OH generation were proven, which would endow Co@Fe MOG with a certain antibacterial ability, promoting the healing of bacteria-infected wounds. In conclusion, this study contributes to the development efforts toward the application systems of nanozymes for marker detection and antibacterial activity.

Interfacial engineering of Ti3C2-TiO2 MXenes by managing surface oxidation behavior for enhanced sonodynamic therapy

As a kind of reactive oxygen species (ROS) mediated therapy, sonodynamic therapy (SDT) has attracted great interest in cancer therapy. However, highly efficient and biocompatible sonosensitizers are urgently required to improve the therapeutic efficiency of SDT. In this work, Ti3C2-TiO2 MXenes were controllably synthesized as good sonosensitizers through interface engineering by regulating the dissolved oxygen concentration of the aqueous solution. The as-prepared Ar-Ti3C2-TiO2 MXene possessed a narrow band gap of 2.37 eV with promoted charge carrier transformation and efficient electron-hole separation. Compared with pure TiO2 sonosensitizers, the Ar-Ti3C2-TiO2 MXene displayed higher US-triggered reactive oxygen species (ROS) generation efficiency. In addition, the structurally maintained Ar-Ti3C2-TiO2 possessed good photothermal conversion efficiency and the laser irradiation could greatly improve the electron-hole pair separation efficiency to further increase the ROS generation capability. After modification with arginyl–glycyl–aspartic (RGD) peptide, the Ar-Ti3C2-TiO2-RGD could efficiently accumulate in the tumor sites and achieve effective PTT enhanced SDT to eliminate tumors after intravenous injection without causing appreciable long-term toxicity. Therefore, this work presented a new way to construct safe sonosensitizers for enhanced SDT and the as-prepared Ar-Ti3C2-TiO2-RGD displayed good potential for further clinical translation. Statement of significanceTo achieve superior tumor treatment, the nanosized TiO2/Ti3C2 heterostructure was controllably synthesized through interface engineering by regulating the dissolved oxygen concentration of the aqueous solution using inert gas. The oxidation-optimized Ar-Ti3C2-TiO2 MXene possessed good sonodynamic performance with a narrow band gap of 2.37 eV and good photothermal conversion efficiency of 47.3% with structurally maintained Ti3C2 MXene. Additionally, the laser irradiation could greatly improve the electron-hole pair separation efficiency to further boost sonodynamic performance of Ar-Ti3C2-TiO2 MXene. Encouragingly, the Ar-Ti3C2-TiO2-RGD could efficiently accumulate in the tumor sites and achieve effective PTT enhanced SDT to eliminate tumors.

ROS-Responsive 4D Printable Acrylic Thioether-Based Hydrogels for Smart Drug Release.

Reactive oxygen species (ROS) play a key role in several biological functions like regulating cell survival and signaling; however, their effect can range from beneficial to nondesirable oxidative stress when they are overproduced causing inflammation or cancer diseases. Thus, the design of tailor-made ROS-responsive polymers offers the possibility of engineering hydrogels for target therapies. In this work, we developed thioether-based ROS-responsive difunctional monomers from ethylene glycol/thioether acrylate (EGnSA) with different lengths of the EGn chain (n = 1, 2, 3) by the thiol-Michael addition click reaction. The presence of acrylate groups allowed their photopolymerization by UV light, while the thioether groups conferred ROS-responsive properties. As a result, smart PEGnSA hydrogels were obtained, which could be processed by four-dimensional (4D) printing. The mechanical properties of the hydrogels were determined by rheology, pointing out a decrease of the elastic modulus (G') with the length of the EG segment. To enhance the stability of the hydrogels after swelling, the EGnSA monomers were copolymerized with a polar monomer, 2-hydroxyethyl acrylate (HEA), leading to P[(EGnSA)x-co-HEAy] with improved compatibility in aqueous media, making it a less brittle material. Swelling properties of the hydrogels increased in the presence of hydrogen peroxide, a kind of ROS, reaching values of ≈130% for P[(EG3SA)7-co-HEA93] which confirms the stimuli-responsive properties. Then, the P[(EG3SA)x-co-HEAy] hydrogels were employed as matrixes for the encapsulation of a chemotherapeutic drug, 5-fluorouracil (5FU), which showed sustained release over time modulated by the presence of H2O2. Finally, the effect of the 5-FU release from P[(EG3SA)x-co-HEAy] hydrogels was tested in vitro with melanoma cancer cells B16F10, pointing out B16F10 growth inhibition values in the range of 40-60% modulated by the EG3SA percentage and the presence or absence of ROS agents, thus confirming their excellent ROS-responsive properties for the treatment of localized pathologies.

The distribution of submerged macrophytes in response to intense solar radiation and salinity reveals hydrogen peroxide as an abiotic stress indicator

The feasible condition for submerged macrophyte growth is hard to understand as many environmental factors contribute to establishing macrophyte distribution with different intensities generating excess reactive oxygen species (ROS). Among various kinds of ROS, hydrogen peroxide (H2O2) is relatively stable and can be measured accurately. Thus, for the quantification of submerged macrophyte species, H2O2 can be used to evaluate their distribution in a lake. Submerged macrophytes, such as Potamogeton anguillanus, were abundant in Lake Shinji. The largest biomass distribution was around 1.35 m deep, under low solar radiation intensity, and nearly no biomass was found less than 0.3 m deep, where solar radiation was high. Tissue H2O2 concentrations varied in response to the diurnal photosynthetically active radiation (PAR) intensity, which was followed by antioxidant activities, though slightly delayed. Laboratory experiments were conducted with different PAR intensities or salinity concentrations. A stable level of H2O2 was maintained up to about 200 μmol m−2 s−1 of PAR for 30 days, followed by a gradual increase as PAR increased. The H2O2 concentration increased with higher salinity. A change in Chlorophyll a (Chl-a) concentration is associated with an altering H2O2 concentration, following a unique negative relationship with H2O2 concentration. If H2O2 exceeded 45 μmol/gFW, the homeostasis collapsed, and H2O2 and Chl-a significantly declined afterward. The above findings indicate that H2O2 has a negative effect on the physiological condition of the plant. The increase in H2O2 concentration was prevented by antioxidant activities, which elevated with increasing H2O2 concentration.

Distinct dual enzyme-like activities of Fe-N-C single-atom nanozymes enable discriminative detection of cellular glutathione.

Fe-N-C single-atom nanozymes readily achieved discriminative detection of glutathione (GSH) over other biothiols with similar structure due to the difference between POD-like and OXD-like activities regarding the kind of reactive oxygen species. This colorimetric sensor demonstrated the heterogeneity of GSH levels in different cells and accurately monitored cellular GSH fluctuation.

A dihydro-benzo[4,5]imidazo[1,2-c]quinazoline-based probe with aggregation-induced ratiometric emission for the ratiometric fluorescent detection of peroxynitrite in living cells and zebrafish.

As a significant kind of reactive oxygen species (ROS), peroxynitrite (ONOO-) plays an indispensable role in many physiological and pathological processes. This study aimed to synthesize a novel dihydro-benzo[4,5]imidazo[1,2-c]quinazoline-based probe 1 for detecting ONOO-. In 99.5% H2O solution, probe 1 displayed a distinct aggregation-induced ratiometric emission (AIRE), and would selectively respond toward ONOO-via a ratiometric fluorescent signal, along with a short response time (<30 s) and ultra-sensitivity (LOD = 17.6 nM). Moreover, the probe was applied for monitoring the concentration fluctuations of ONOO- in HeLa cells and zebrafish.

Improving the removal of tetracycline via carbonate-mediated triplet-excited state by the Cu-containing zeolites activated percarbonate

The removal of tetracycline (TC) via various advanced oxidation processes (AOPs) under visible light has been widely investigated. However, the photosensitive effect of TC on its removal has been mostly neglected. In this work, the photosensitization of TC is explored by a novel catalytic system, Cu-containing zeolite (Cu/ZSM5) activation on sodium percarbonate (SPC) under visible light irradiation. Experimental results indicated that the Cu/ZSM5/vis/SPC process could achieve 100 % removal of TC within 40 min (kobs = 0.099 min−1), while only removal of 58.1 % was achieved under dark conditions (kobs = 0.016 min−1). It was confirmed for the first time by phosphorescence spectroscopy that carbonate ions (CO32–) could induce TC to be excited into triplet states (3TC*) under visible light, synergistically forming the carbonate radicals (•CO3−). Besides, the CO32– reacted with hydroxyl radical (•OH) derived from the heterogeneous Fenton-like pathway by Cu/ZSM5, leading to the generation of multiple kinds of reactive oxygen species (•OH, •CO3−, •O2−, and 1O2), which further together contribute to the TC removal. This study does not only present a novel strategy via Cu-containing zeolite with SPC to remove TC but also found that TC acts as both a sensitizer and oxidized substrate.

A novel near-infrared fluorescent probe for rapid sensing of HClO in living cells and zebrafish.

Reactive oxygen species (ROS) are significant active species in living organisms, and their coordination maintains the function of organelles to resist the invasion of foreign substances. Hypochlorous acid (HClO) is not only an eventful signaling species but also a kind of ROS, which plays an irreplaceable role in the immune system. However, its abnormal levels can cause cell damage or even apoptosis, which in turn leads to the onset of a series of diseases such as inflammation, neurological diseases, and even cancer. Based on this, we designed a near-infrared fluorescent probe with a large Stokes shift for ultrafast response to HClO. Furthermore, the probe exhibits excellent sensitivity and selectivity toward HClO over other species. The probe was successfully applied to visualize endogenous and exogenous HClO in living cells and in zebrafish. This unique study is the key to providing a trustworthy tool for imaging based on the in vitro and in vivo imaging of endogenous HClO, which possesses great potential for the use in future studies of HClO-related biology and pathology.

A Nile red-based near-infrared fluorescent probe for the detection of superoxide radical anion in living cells

Reactive oxygen species (ROS) are important products of aerobic metabolism and play important roles in many physiological and pathological processes. Among the ROS, superoxide radical anion (O 2 •‒ ) is a primary ROS and precursor of a few other kinds of ROS. O 2 •‒ is widely involved in regulating cell functions and is a critical biomarker for monitoring cellular stress responses. Thus, a real-time quantitative detection of O 2 •‒ is of great significance in ascertaining the pathological roles of O 2 •‒ in related diseases. Herein we report a near-infrared (NIR) fluorescent probe NR1 for the sensitive detection and imaging of O 2 •‒ , which is rationally designed and synthesized through an esterification reaction of a Nile red dye and the diphenyl phosphinyl group. The NR1 probe exploits the strong nucleophilic mechanism of O 2 •‒ as a novel detection strategy, which leads to the cleavage of NR1 to yield Nile red as the fluorescence reporter and diphenyl phosphinyl functional group as the responsive unit. The developed NR1 probe exhibits highly sensitive, selective and rapid fluorescence turn-on response on addition of O 2 •‒ in the presence of potential ROS interfering species. Furthermore, the probe NR1 is successfully applied in imaging of various cancer cell lines (4T1 and Hela) and excellent imaging ability of O 2 •‒ in vitro is achieved. Biocompability of NR1 is also evaluated through MTS assay. The present study provides a novel strategy for molecular design of NIR fluorescent probe and the resulting probe shows great potential for practical application in complex bio-systems to study the development and progression of related diseases.

A novel Golgi-targetable fluorescent probe for imaging peroxynitrite in Golgi stress and sepsis-induced acute lung injury

The Golgi apparatus is a crucial component of the endomembrane system and is involved in various physiological and pathological processes. Recently, increasing evidence shows that Golgi participates in oxidative stress in sepsis-induced acute lung injury (ALI). As a kind of reactive oxygen species (ROS), peroxynitrite (ONOO−) plays a significant role in a range of oxidative stress-related diseases. Therefore, accurately monitoring the level of ONOO− in the Golgi apparatus is crucial for revealing the mechanism of Golgi ONOO− in the sepsis-induced ALI. Unfortunately, no such probe has been reported to detect Golgi ONOO− in sepsis-induced ALI model. In this work, a Golgi-targetable probe FC-ONOO was designed and synthesized for high sensitivity and selectivity monitoring ONOO− generation during the Golgi stress response in sepsis-induced ALI model. The probe displayed high sensitivity (about 57 nM of detection limit) and good selectivity towards ONOO−. Additionally, it was successfully applied in mapping the increase of ONOO− levels in the Golgi of live cells induced by different stimuli. More importantly, the substantial increases in ONOO− levels in the Golgi apparatus were observed in the sepsis-induced ALI of mice for the first time. Given all its outstanding advantages, it has great potential for application in other ONOO− related diseases.

Dual stimulus-responsive core-satellite SERS nanoprobes for reactive oxygen species sensing during autophagy

As one kind of reactive oxygen species, hydrogen peroxide (H2O2) participated in various cellular biological processes including cell differentiation and inflammation responses. Abnormal H2O2 level is closely related to cancer and other diseases. Highly sensitive detection and monitoring H2O2 are of great importance for understanding the roles of H2O2 in cellular dynamic events. Herein, a novel dual stimulus-responsive core-satellite surface-enhanced Raman scattering (SERS) nanoprobe engineered with manganese dioxide (MnO2) and silver nanoparticles (Ag NPs) was constructed for sensitive H2O2 detection. The sensing strategy is based on the target-triggered degradation both of the “core” and “satellite”. In this system, the MnO2 core not only could be used as solid supporter to generate “hot spots” that can induce strong SERS signals, but also acted as the responsive unit for H2O2 sensing together with Ag NPs. A good linear relationship in the range from 1 to 100 μM and limit of detection of 7.44 μM were obtained. Moreover, the nanosensor possessed good repeatability. Based on this strategy, the sensitive detection of cellular H2O2 was achieved. Furthermore, the SERS-based H2O2 monitoring during the starvation-induced autophagy was realized by the developed nanoprobes. Our study provides a new way for sensitive H2O2 detection and opens a new avenue for sensing and detection of other biomolecules.

Dicer induced reactive oxygen species inhibit hepatocellular carcinoma through interacting with cytochrome c oxidase

Dicer is an RNaseIII in microRNA processing that modulates multiple biological processes including tumorigenesis. We have shown that Dicer could inhibit the growth of hepatocellular carcinoma (HCC) previously [Zhang L, Wang C, Liu S, Zhao Y, et al. Oncol Lett 2016;11:3961-3966]. Here, we evaluated the relationships between Dicer and reactive oxygen species (ROS) as well as their modulation for HCC. We found Dicer expression was positively associated with ROS generation in HCC tissue at borderline statistical levels (p = .065); functional analysis showed Dicer could both induce the ROS generation (p < .01) and reduce the activity of Cytochrome c Oxidase (COX) (p < .05) by comparing the Dicer transfected and control HCC cells. The COX inhibitor ADDA-5 hydrochloride could increase the ROS generation, whereas the ROS scavenger N-acetylcysteine (NAC) could decrease the COX activity. Further analysis also demonstrated that one kind of ROS, H2O2, could repress the proliferation and migration as well as increase the apoptosis of HCC cells. Our data indicated that Dicer could inhibit the HCC growth by promoting ROS generation; ROS and COX interacted with each other to modify this process.

A novel colorimetric and ratiometric fluorescent probe for monitoring lysosomal HOCl in real time

Hypochlorous acid (HOCl), a kind of reactive oxygen species (ROS), is involved in numerous lysosomal functions. Abnormal excess or deficiency of HOCl in lysosome could not only disrupt control of apoptosis, but also relates to numerous neurodegenerative diseases. However, monitoring the subtle concentration change of lysosomal HOCl in vivo is limited. Herein, a highly sensitive ratiometric fluorescent probe (NAP-RS) was rationally designed for measuring lysosomal HOCl fluctuations. NAP-RS provides a clear ratiometric fluorescence response to HOCl with large emission gap (186 nm), rapid maximum response time (<3 s) and ultrasensitivity (limit of detection = 36 nM) at biologically-relevant concentrations. In addition, NAP-RS can be efficiently employed to visualize exogenous and endogenous lysosomal HOCl. As a matter of fact, this work will provide a new way for the improved measurement of lysosomal HOCl, and a general molecular design methodology for the facile preparation of more refined fluorescent probes.

Kinetics and mechanisms for sulfamethoxazole transformation in the phenolic acid-laccase (Trametes versicolor) system.

Oxidation of phenolic acids (PCs) by laccase could produce various kinds of reactive oxygen species (ROS), which is expected to have substantial impact on the transformation of antibiotics like sulfamethoxazole (SMX) in soil and aquatic environments. In this study, the formation of semiquinones radical (SQ●-), superoxide anion radical (O2●-), hydrogen peroxide (H2O2), hydroxyl radical (●OH), and singlet oxygen (1O2) in a laccase-gallic acid (GA) reaction system was confirmed. Meanwhile, GA would be transformed to its monomeric quinone and quinones of di- and tri-polymers. Transformation of SMX by laccase alone is negligible, while which was greatly enhanced in the presence of GA at the optimal pH of 5.5. The dissolved O2 was the requisite for transformation of SMX due to its fundamental role in the formation of SQ●-, the key species initializing the chain reactions for the generation of other ROS. The quenching experiments indicated O2●- and 1O2 were the main ROS responsible for SMX transformation. A total of thirteen products were proposed for the SMX transformation, with the pathways including the breaking of S-N bond, the cleavage of oxazole ring, electrophilic substitution, Michael addition, and condensation reactions. Moreover, the existence of electron-withdrawing substitution group on the benzene ring of PCs and less stability of SQ●- was believed to be favorable for the transformation of SMX. The results above expand our understanding on the role of oxidation of PCs by laccase in the SMX transformation in environments and are of significance in relation to use of laccase in dealing with SMX pollution.

A red-emission iridium (Ⅲ) complex-based fluorescent probe with Schiff base structure for selection detection HOCl and its application in water sample

Hypochlorous acid (HOCl), a kind of reactive oxygen species (ROS), has been reported to be related to many human diseases, such as Parkinson's diseases, arthritis and cancers. Herein, a red-emission Ir(III) complex-based probe 1 for quantitative detection of HOCl was prepared and characterized by 1H and 13C NMR, IR and HRMS. For probe 1, benzenesulfonylhydrazine group was introduced to the main N^C ligands phenylpyridine to quench fluorescence due to the isomerization of C = N bond. After reaction with HOCl in 30% DMF/PBS solution, the benzenesulfonylhydrazine group was taken off and fluorescent complex Ir-CHO was generated. The fluorescence intensity at 625 nm was significantly enhanced, and finally increased by 23 times. The experiment results demonstrated that probe 1 possessed large Stokes shift (ca. 195 nm), low detection limit (1.3728 × 10−6 M), fast response (25 s), and high selectivity toward HOCl without interference from other ions and bio-related species. In addition, probe 1 exhibited good stability and water solubility. Moreover, it could be further applied in actual water for quantitative detection of HOCl with high recovery rate (95% − 101%).

Genome-Wide Identification and Expression Analysis of the Thioredoxin (Trx) Gene Family Reveals Its Role in Leaf Rust Resistance in Wheat (Triticum aestivum L.).

Bread wheat (Triticum aestivum L.; Ta) is the staple cereal crop for the majority of the world’s population. Leaf rust disease caused by the obligate fungal pathogen, Puccinia triticina L., is a biotrophic pathogen causing significant economic yield damage. The alteration in the redox homeostasis of the cell caused by various kinds of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in response to pathogenic infections is controlled by redox regulators. Thioredoxin (Trx) is one of the redox regulators with low molecular weight and is thermostable. Through a genome-wide approach, forty-two (42) wheat Trx genes (TaTrx) were identified across the wheat chromosome groups A, B, and D genomes containing 12, 16, and 14 Trx genes, respectively. Based on in silico expression analysis, 15 TaTrx genes were selected and utilized for further experimentation. These 15 genes were clustered into six groups by phylogenetic analysis. MicroRNA (miRNA) target analysis revealed eight different miRNA-targeted TaTrx genes. Protein–protein interaction (PPI) analysis showed TaTrx proteins interact with thioredoxin reductase, peroxiredoxin, and uncharacterized proteins. Expression profiles resulting from quantitative real-time PCR (qRT-PCR) revealed four TaTrx genes (TaTrx11-5A, TaTrx13-5B, TaTrx14-5D, and TaTrx15-3B) were significantly induced in response to leaf rust infection. Localization of ROS and its content estimation and an assay of antioxidant enzymes and expression analysis suggested that Trx have been involved in ROS homeostasis at span 24HAI-72HAI during the leaf rust resistance.

Phycocyanin - carbon dots nanoprobe for the ratiometric fluorescence determination of peroxynitrite

As a kind of reactive oxygen species, peroxynitrite is related to various diseases closely such as cancer and neurodegenerative diseases. Constructing probes with highly specific ability and a wide linear detection range for peroxynitrite detection is crucial for understanding the pathogenesis of related diseases and optimizing treatments. In this work, we developed a novel luminescent ratiometric fluorescence nanoprobe (PC-CDs) based on carbon dots and phycocyanin. PC-CDs are constructed by amidation reaction between carbon dots and phycocyanin. The nanoprobe we obtained has a good ability of distinguishing peroxynitrite from other reactive oxygen species and interfering substances. Moreover, the linear range of the nanoprobe is 0.5–100 μM and the limit of detection is 0.5 μM when detecting peroxynitrite. In the spiked recovery experiments under phosphate buffered saline (PBS) environment, our nanoprobe has a good recovery performance and the recovery is 99% − 104%, which will be beneficial to the further development of peroxynitrite testing and the research progress of related diseases. Finally, we discuss the quenching mechanism of peroxynitrite for nanoprobe, and found that there is the combination of dynamic and static quenching in the quenching process.