Detection Of Reactive Oxygen Species Research Articles

Screen-printed, biocompatible and ultrasensitive sensor for real-time reactive oxygen species detection in human sweat

Excessive or burst generation of reactive oxygen species (ROS) can induce oxidative stress, precipitating a range of critical illnesses, including cancers, Parkinson's disease and Ischemia-reperfusion injury. Conventional biological assays for ROS, involving discrete steps of capturing, labelling, and spectrometric detection, are complex and time-intensive. Moreover, their accuracy is substantially compromised by the short lifespan (microseconds to milliseconds) of ROS. Consequently, there is a pressing need for a rapid and efficient method that enables real-time detection. In this study, we have developed a printable, flexible ROS sensor based on a robust nanoenzyme composite by direct deposition of the paste onto a flexible polyethylene terephthalate (PET) substrate. This device demonstrated the fast and real-time responses to the hydrogen peroxide (mimetic agent) in the laboratory and to total ROS in sweat of an individual, exhibiting an outstanding current response to hydrogen peroxide across a broad concentration range of 0.01–10 mM, with a limit of detection (LOD) of 1.85 μM. The device's sensitivity to hydrogen peroxide (136.59 μA mM−1 cm−2), was found to be 1.5 to 10 times higher than that of sensors previously reported. Moreover, the IFRS device successfully identified instantaneous ROS levels in the sweat of adult males in vitro, with amperometric response increased 8 times after half an hour strenuous exercise, thereby exhibiting excellent selectivity, remarkable stability, and confirmed high biosafety. Overall, the IFRS provides a viable and practical solution for simple, expedited, and real-time ROS detection in the near future.

Transcriptome Analysis Revealed ZmPTOX1 Is Required for Seedling Development and Stress Tolerance in Maize.

Plant seedling morphogenesis is considerably related to photosynthesis, pigment synthesis, and circadian periodicity during seedling development. We identified and cloned a maize zebra or crossbanding leaves mutant wk3735, which produces pale white kernels and was identified and plays a role in the equilibrium of the Redox state the in/out of ETC by active oxygen scavenging. Interestingly, it produces the zebra leaves during the production of the first seven leaves, which is apparently different from the mutation of homologs AtPTOX in Arabidopsis. It is intriguing to investigate how and why yellow crossbands (zebra leaf phenotype) emerge on leaves. As expected, chlorophyll concentration and photosynthetic efficiency both significantly declined in the yellow sector of wk3735 leaves. Meanwhile, we observed the circadian expression pattern of ZmPTOX1, which was further validated by protein interaction assays of the circadian clock protein TIM1 and ZmPTOX1. The transcriptome data of yellow (muW) and green (muG) sectors of knock-out lines and normal leaves of overexpression lines (OE) at the 5th-leaf seedling stage were analyzed. Zebra leaf etiolated sections exhibit a marked defect in the expression of genes involved in the circadian rhythm and rhythmic stress (light and cold stress) responses than green sections. According to the analysis of co-DEGs of muW vs. OE and muG vs. OE, terms linked to cell repair function were upregulated while those linked to environmental adaptability and stress response were downregulated due to the mutation of ZmPTOX1. Further gene expression level analyses of reactive oxygen species (ROS) scavenging enzymes and detection of ROS deposition indicated that ZmPTOX1 played an essential role in plant stress resistance and ROS homeostasis. The pleiotropic roles of ZmPTOX1 in plant ROS homeostasis maintenance, stress response, and circadian rhythm character may collectively explain the phenotype of zebra leaves during wk3735 seedling development.

Dual-mode optical biocompatible-sensor enabled by enzyme-like activity of UiO-66 (Zr) for ultra-sensitive ROS detection in vitro

The simple, effective and highly sensitive detection of hydrogen peroxide (H2O2), which belongs to the reactive oxygen species (ROS), at low concentrations plays an indispensable role in the field of environmental protection, biological research and safety. In this study, a dual-mode optical biosensor, UiO-66@OPD, was developed based on the inherent peroxidase mimicking activity of UiO-66 (Zr) and the optical reaction of ortho-phenylenediamine (OPD) by extending the π-system through oxidative coupling, prototropism and elimination to form OPDox, thereby exhibiting strong orangish absorbance and greenish fluorescence. The catalase-mimicking activity of UiO-66 (Zr) was demonstrated by the catalytic oxidation of methylene blue in the presence of H2O2. Moreover, the Michaelis-Menten kinetic model confirmed the intrinsic peroxidase-like activity of UiO-66@OPD as a modified MOFzyme. The synthesized UiO-66 (Zr) facilitated the oxidation of OPD to OPDox by degrading H2O2 to the hydroxyl radicals. During the oxidation process, the absorption peak at 415 nm and the fluorescence peak at 565 nm of the synthesized probe were significantly enhanced by increasing the H2O2 concentration. Moreover, a colorimetric and fluorometric ultrasensitive sensor shows a good linear relationship between the intensity enhancement and H2O2 concentration in the range of 0–600 nM for absorption and fluorescence spectra with R2 = 0.9772, and R2 = 0.9948, respectively. To demonstrate the biological performance and biocompatibility of UiO-66@OPD as a biosensor, MTT evaluation was performed for the three cell lines MCF-10 A, HEK293 and A549, indicating high biocompatibility and good cell viability for biological applications. Ultimately, this convenient, environmentally friendly, biocompatible and cost-effective catalase-mimicking-based sensor system will open a new perspective for the development of portable kite-based biosensors In vitro.

Upconversion nanoparticles-CuMnO2 nanoassemblies for NIR-excited imaging of reactive oxygen species in vivo

Here, we designed a ratiometric luminescent nanoprobe based on lanthanide-doped upconversion nanoparticles-CuMnO2 nanoassemblies for rapid and sensitive detection of reactive oxygen species (ROS) levels in living cells and mouse. CuMnO2 nanosheets exhibit a wide absorption range of 300–700 nm, overlapping with the visible-light emission of upconversion nanoparticles (UCNPs), resulting in a significant upconversion luminescence quenching. In an acidic environment, H2O2 can promote the redox reaction of CuMnO2, leading to its dissociation from the surface of UCNPs and the restoration of upconversion luminescence. The variation in luminescence intensity ratio (UCL475/UCL450) were monitored to detect ROS levels. The H2O2 nanoprobe exhibited a linear response in the range of 0.314–10 μM with a detection limit of 11.3 nM. The biological tests proved the excellent biocompatibility and low toxicity of obtained UCNPs-CuMnO2 nanoassemblies. This ratiometric luminescent nanoprobe was successfully applied for the detection of exogenous and endogenous ROS in live cells as well as in vivo ROS quantitation. The dual transition metal ions endow this probe efficient catalytic decomposition capabilities, and this sensing strategy broadens the application of UCNPs-based nanomaterials in the field of biological analysis and diagnosis.

Olanzapine Induces Adipogenesis and Glucose Uptake by Activating Glycolysis and Synergizing with the PI3K-AKT Pathway.

Administration of olanzapine (OLA) is closely associated with obesity and glycolipid abnormalities in patients with schizophrenia (SCZ), although the exact molecular mecha- nisms remain elusive. We conducted comprehensive animal and molecular experiments to elucidate the mecha- nisms underlying OLA-induced weight gain. We investigated the mechanisms of OLA-induced adipogenesis and lipid storage by em- ploying a real-time ATP production rate assay, glucose uptake test, and reactive oxygen species (ROS) detection in 3T3-L1 cells and AMSCs. Rodent models were treated with OLA using various interven- tion durations, dietary patterns (normal diets/western diets), and drug doses. We assessed body weight, epididymal and liver fat levels, and metabolic markers in both male and female mice. OLA accelerates adipogenesis by directly activating glycolysis and its downstream PI3K sig- naling pathway in differentiated adipocytes. OLA promotes glucose uptake in differentiated 3T3-L1 preadipocytes. In mouse models with normal glycolipid metabolism, OLA administration failed to in- crease food intake and weight gain despite elevated GAPDH expression, a marker related to glycolysis and PI3K-AKT. This supports the notion that glycolysis plays a significant role in OLA-induced met- abolic dysfunction. OLA induces glycolysis and activates the downstream PI3K-AKT signaling pathway, thereby promoting adipogenesis.

Understanding the Role of Corrosion and Reactive Oxygen Species in Electrochemical Ozone Production on Nickel and Antimony Doped Tin Oxide

Electrochemical ozone production (EOP), a six-electron reaction, offers promising green applications for water disinfection and organic synthesis. Nickel and antimony-doped tin oxide (Ni/Sb-SnO2, NATO) electrodes are known to be active for EOP. Still, the mechanism of NATO's selectivity and activity and the origin of its instability need to be clarified. We combine electrochemistry, spectroscopic detection of reactive oxygen species (ROS) using selective chemical probes, oxygen anion chemical ionization mass spectrometry (CIMS), and density-functional theory (DFT) simulations to identify the reaction mechanism and investigate the role of corrosion and homogenous reactive oxygen species in EOP on NATO electrodes. We identify hydrogen peroxide as a critical reaction intermediate. Our results suggest that the presence of nickel in NATO enables the catalysis of hydrogen peroxide to hydroperoxyl radicals, which subsequently undergo oxidation to produce ozone. The isotopic makeup of products shows that water is the primary source of ozone, but it also contains oxygen from the metal oxide lattice. The change in the isotopic generation pattern of ozone suggests that NATO catalysts corrode irreversibly, and the lattice oxygen is not regenerated, explaining NATO's instability.

In Vitro Effect of Epigallocatechin Gallate on Heme Synthesis Pathway and Protoporphyrin IX Production.

Photodynamic therapy (PDT) treats nonmelanoma skin cancer. PDT kills cells through reactive oxygen species (ROS), generated by interaction among cellular O2, photosensitizer and specific light. Protoporphyrin IX (PpIX) is a photosensitizer produced from methyl aminolevulinate (MAL) by heme group synthesis (HGS) pathway. In PDT-resistant cells, PDT efficacy has been improved by addition of epigallocatechin gallate (EGCG). Therefore, the aim of this work is to evaluate the effect of EGCG properties over MAL-TFD and PpIX production on A-431 cell line. EGCG's role over cell proliferation (flow cytometry and wound healing assay) and clonogenic capability (clonogenic assay) was evaluated in A-431 cell line, while the effect of EGCG over MAL-PDT was determined by cell viability assay (MTT), PpIX and ROS detection (flow cytometry), intracellular iron quantification and gene expression of HGS enzymes (RT-qPCR). Low concentrations of EGCG (<50 µM) did not have an antiproliferative effect over A-431 cells; however, EGCG inhibited clonogenic cell capability. Furthermore, EGCG (<50 µM) improved MAL-PDT cytotoxicity, increasing PpIX and ROS levels, exerting a positive influence on PpIX synthesis, decreasing intracellular iron concentration and modifying HGS enzyme gene expression such as PGB (upregulated) and FECH (downregulated). EGCG inhibits clonogenic capability and modulates PpIX synthesis, enhancing PDT efficacy in resistant cells.

Long non-coding RNA TPT1-AS1 inhibits ferroptosis in ovarian cancer by regulating GPX4 via CREB1 regulation.

Long non-coding RNAs (lncRNAs) play crucial roles in cellular processes, with dysregulation implicated in various diseases, including cancers. The lncRNA TPT1-AS1 (TPT1 Antisense RNA 1) promotes tumor progression in several cancers, including ovarian cancer (OC), but its influence on ferroptosis and interaction with other proteins remains underexplored. In this study, we employed a multi-faceted approach to investigate the functional significance of TPT1-AS1 in OC. We assessed TPT1-AS1 expression in OC specimens and cell lines using RT-qPCR, in situ hybridization (ISH), and fluorescence in situ hybridization (FISH) assays. Functional assays included evaluating the impact of TPT1-AS1 knockdown on OC cell proliferation, migration, invasiveness, and cell cycle progression. Further, we explored and validated the interaction of TPT1-AS1 with other proteins using bioinformatics. Finally, we investigated TPT1-AS1 involvement in erastin-induced ferroptosis using Iron Assay, Malondialdehyde (MDA) assay, and reactive oxygen species (ROS) detection. Our findings revealed that TPT1-AS1 overexpression in OC correlated with an unfavorable prognosis. TPT1-AS1 knockdown suppressed cell proliferation, migration, and invasiveness. Additionally, TPT1-AS1 inhibited erastin-induced ferroptosis, and in vivo experiments confirmed its oncogenic impact on tumor development. Mechanistically, TPT1-AS1 was found to regulate Glutathione Peroxidase 4 (GPX4) transcription via CREB1 (cAMP response element-binding protein 1) and interact with RNA-binding protein (RBP) KHDRBS3 (KH RNA Binding Domain Containing, Signal Transduction Associated 3) to regulate CREB1. TPT1-AS1 promotes OC progression by inhibiting ferroptosis and upregulating CREB1, forming a regulatory axis with KHDRBS3. These findings highlight the regulatory network involving lncRNAs, RBPs, and transcription factors in cancer progression.

Levonorgestrel protected Au10 cluster for hypochlorite sensing in living organisms

BackgroundHighly reactive oxygen species (ROS) could lead to serious damage in living cells and are associated with many diseases like cancers. Metal cluster with strong fluorescence has great potential in biosensing and many thiolate ligands-protected clusters have been applied in ROS sensing. ResultsIn this work, we synthesized levonorgestrel protected Au10 cluster with specific sensing ability for highly ROS via crystal transformation from Au8 cluster, demonstrating the significance of inner core structure on detecting performance. The detection limit of Au10 cluster for ClO− could reach as low as 0.1 μM. This fluorescent probe not only achieving detection of exogenous ClO− in living cells and zebrafish, but also successful imaging of endogenous ClO− in HeLa and HepG2 cells. SignificanceIn comparison to previously reported cluster-based sensors for ROS, this work proposes a different reaction mechanism of metal nanoclusters for ROS detection (breakage of gold-alkynyl bond and oxidation of alkynyl group). This provides new directions for designing specific ROS probes and broadens the applications of metal clusters in disease diagnostics.

CircCOL5A1 is involved in proliferation, invasion, and inhibition of ferroptosis of colorectal cancer cells via miR-1287-5p/SLC7A11.

Colorectal cancer (CRC) is the leading cause of cancer-related death globally. Circular RNA circCOL5A1 plays an oncogene function in a variety of tumors. However, the function of circCOL5A1 in CRC is still unknown. Here, we aimed to elucidate the function and mechanism of circCOL5A1 in CRC. The correlation between circCOL5A1 and CRC clinicopathological was assessed through chi-square. The relevance between circCOL5A1 and CRC patient survival time was evaluated by Kaplan-Meier analysis. The expressions of circCOL5A1 in CRC were determined via quantitative real-time PCR. The function of circCOL5A1 in CRC was analyzed with Cell Counting Kit-8, EdU assay, Transwell, detection of reactive oxygen species and Fe2+ levels, and Western blot analysis. Moreover, the mechanism of circCOL5A1 was determined by dual-luciferase reporter assay, RNA immunoprecipitation, and RNA pull-down. Finally, the role of circCOL5A1 in vivo was elucidated through a mouse xenograft model, hematoxylin-eosin staining, and immunohistochemistry. CircCOL5A1 expression was increased in CRC, and increased circCOL5A1 levels were related to TNM stage, lymph node metastasis, distant metastasis, and tumor differentiation in CRC patients, and CRC patients with high circCOL5A1 levels had a low overall survival rate. For the circCOL5A1 function in CRC, we found that circCOL5A1 knockdown weakened CRC cell proliferation and invasion, and enhanced cell ferroptosis. For the circCOL5A1 mechanism in CRC, we further confirmed that circCOL5A1 bound to miR-1287-5p, miR-1287-5p bound to SLC7A11. SLC7A11 was negatively interrelated to miR-1287-5p and was positively interrelated to circCOL5A1 in CRC tissues. Furthermore, interfering circCOL5A1 decreased SLC7A11 expression, and this trend was abolished through miR-1287-5p cotransfection. Rescue assays further demonstrated that circCOL5A1 knockdown alleviated CRC cell malignant phenotype via miR-1287-5p/SLC7A11. Moreover, interference with circCOL5A1 reduced CRC growth in vivo. CircCOL5A1 functioned as an oncogene in CRC via miR-1287-5p/SLC7A11.

Integrating Pt nanoparticles with 3D Cu2- x Se/GO nanostructure to achieve nir-enhanced peroxidizing Nano-enzymes for dynamic monitoring the level of H2O2 during the inflammation.

The treatment of wound inflammation is intricately linked to the concentration of reactive oxygen species (ROS) in the wound microenvironment. Among these ROS, H2O2 serves as a critical signaling molecule and second messenger, necessitating the urgent need for its rapid real-time quantitative detection, as well as effective clearance, in the pursuit of effective wound inflammation treatment. Here, we exploited a sophisticated 3D Cu2- x Se/GO nanostructure-based nanonzymatic H2O2 electrochemical sensor, which is further decorated with evenly distributed Pt nanoparticles (Pt NPs) through electrodeposition. The obtained Cu2- x Se/GO@Pt/SPCE sensing electrode possesses a remarkable increase in specific surface derived from the three-dimensional surface constructed by GO nanosheets. Moreover, the localized surface plasma effect of the Cu2- x Se nanospheres enhances the separation of photogenerated electron-hole pairs between the interface of the Cu2- x Se NPs and the Pt NPs. This innovation enables near-infrared light-enhanced catalysis, significantly reducing the detection limit of the Cu2- x Se/GO@Pt/SPCE sensing electrode for H2O2 (from 1.45 μM to 0.53μM) under NIR light. Furthermore, this biosensor electrode enables in-situ real-time monitoring of H2O2 released by cells. The NIR-enhanced Cu2- x Se/GO@Pt/SPCE sensing electrode provide a simple-yet-effective method to achieve a detection of ROS (H2O2、-OH) with high sensitivity and efficiency. This innovation promises to revolutionize the field of wound inflammation treatment by providing clinicians with a powerful tool for accurate and rapid assessment of ROS levels, ultimately leading to improved patient outcomes.

A novel member of miR169 family negatively regulates maize resistance against Bipolaris maydis.

MicroRNAs (miRNAs) have been confirmed to play important roles in plant defense response. However, the key maize miRNAs involved in the defense response against Bipolaris maydis are very limited. In this study, a novel member of the miR169 family in response to B. maydis, named zma-miR169s, was discovered and investigated. The expression levels of pre-miR169s and zma-miR169s were significantly repressed during B. maydis infection. CRISPR/Cas9-induced zma-miR169s mutant exhibited more resistance against B. maydis, whereas overexpression zma-miR169s enhanced susceptibility, supporting that zma-miR169s might play a negative role in maize resistance. Moreover, RNA-seq and GO analysis showed that differentially expressed genes were highly enriched in the oxidation-reduction process and plant hormone pathway. Hence, reactive oxygen species (ROS) and plant hormone levels were further investigated. ROS detection confirmed that zma-miR169s mutant accumulated more ROS, while less ROS was detected in transgenic maize OE-miR169s. Furthermore, more remarkable changes in PR-1 expression levels and salicylic acid (SA) contents were detected in zma-miR169s mutant compared to wild-type and transgenic maize during B. maydis infection. Additionally, nuclear transcription factors (NF-YA1 and NF-YA13) were identified as targets regulated by zma-miR169s through the agrobacterium-mediated transient expression method. Overexpression of ZmNF-YA13 enhanced Arabidopsis resistance to Pseudomonas syringae pv. tomato DC3000. Taken together, our results suggest that zma-miR169s negatively regulate maize defense responses by influencing ROS accumulation and the SA-dependent signaling pathway.

Inhalable explosive nanosensor for real-time visual monitoring of therapeutic effects of lung cancer

Lung cancer, as one of the major diseases that endanger human health, has a very high fatality rate. Consequently, effective evaluation of clinical treatment outcomes for lung cancer is crucial for the formulation of subsequent treatment plans for patients. In this work, we utilized amorphous calcium carbonate nanoparticles (CaCO3 NPs) as sources of calcium ions (Ca2+) to develop CPs (CaCO3@PDA) core–shell nanoprobes. Concurrently, we functionalized the surface of gold nanoparticles with Cy5.5-peptide, AS1411, and (4-aminosulfonylphenyl) boronic acid (4-APBA) to produce APAAs (Au NPs@pep-AS1411-(4-APBA)), which were further assembled with CPs using PEG to construct an innovative explosive nanosensor, CPAs (CaCO3@PDA-APAAs). The CPs component of the nanosensor could cause the release of a substantial amount of Ca2+ in response to the tumor microenvironment (TME), which in turn induced cellular Ca2+ overload and subsequent apoptosis. This event triggers caspase-3 activation, causing the cleavage of a specific peptide sequence (DEVD), resulting in the fluorescence signal being reinstated. Additionally, the 4-APBA moiety on the probe interacted with H2O2 resulting in alterations in surface-enhanced Raman spectroscopy (SERS) signals, which aided in the detection of reactive oxygen species (ROS) during the physiological processes. By utilizing atomization, the nanoprobes were strategically deposited in the affected lung regions to enhance the fluorescence imaging capabilities and effectively mirror the therapeutic outcomes. Overall, the CPAs explosive nanosensor has a potential in advancing the non-invasive visual monitoring of lung cancer prognosis and can be a valuable tool in ongoing efforts to improve the management of this challenging disease.

Lycopene alleviates Deoxynivalenol-induced toxicity in Porcine intestinal epithelial cells by mediating mitochondrial function

Deoxynivalenol (DON) is widely found in food and feed, posing a threat to human and animal health. Lycopene (Lyc) is a natural plant extracts with significant antioxidant properties. This study was conducted to investigate the protective effects of Lyc on IPEC-J2 cells upon DON exposure. The detection of cell viability and trypan blue staining showed that Lyc alleviated cell damage and decreased cell apoptotic rate induced by DON. The analysis of reactive oxygen species (ROS) level and antioxidant parameter measurements showed that Lyc significantly down-regulated the content of ROS and restored antioxidant enzyme activity. Furthermore, mitochondrial membrane potential (ΔΨm) detection, mitochondrial DNA copy number (mtDNAcn) assay and adenosine triphosphate (ATP) concentration detection showed Lyc improved mitochondrial function after DON exposure. The results of transcriptome analysis, ROS detection and CCK8 assay suggested that Lyc may activated the oxidative phosphorylation (OXPHOS) to improve mitochondrial function. Conclusively, our results suggested that Lyc alleviated DON-induced oxidative stress by improving mitochondrial function through OXPHOS signaling pathway.

Honokiol Mitigates Metabolic-Associated Fatty Liver Disease by Regulating Nrf2 and RIPK3 Signaling Pathways.

Metabolic-associated fatty liver disease (MAFLD) is a common cause of chronic liver disease worldwide. However, there is currently no recognized effective drugs for treating it. In this study, we investigated the efficacy of Honokiol (HNK) in vitro for mitigating MAFLD. Then, 0.4 mM palmitic acid (PA) and LO2 cells were used to establish the MAFLD model. The protective effect of HNK on MAFLD was confirmed by Oil Red O staining and cell counting kit (CCK-8) assay in LO2 cell line. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were carried out to analyze the regulatory role of HNK on Nrf2 and RIPK3 signaling pathways. The effect of HNK and its downstream signaling pathways on oxidative stress were verified by the detection of reactive oxygen species (ROS), malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD). The concentration of IL-1β, IL-6L, and TNF-α was assessed by enzyme-linked immunosorbent assay (ELISA). The middle concentration of HNK (50 μmol/L) was selected as the best option for inhibiting lipidosis and oxidative stress in MAFLD models. Honokiol mitigates MAFLD via activation of nuclear factor E2-related factor 2 (Nrf2) signaling pathways in vitro. Honokiol suppressed MAFLD via activating the Nrf2 signaling pathway to play an antioxidant and anti-inflammatory role. Also, HNK regulates Nrf2 and RIPK3 signaling pathways to mitigate MAFLD. Our results showed that HNK may suppress the oxidative stress and inflammation in MAFLD via activation of Nrf2 signaling pathway.

Inhibitory Action of 1,3,5-Trihydroxybenzene on UVB-Induced NADPH Oxidase 4 through AMPK and JNK Signaling Pathways.

Specific sensitivity of the skin to ultraviolet B (UVB) rays is one of the mechanisms responsible for widespread skin damage. This study tested whether 1,3,5-trihydroxybenzene (THB), a compound abundant in marine products, might inhibit UVB radiation-induced NADPH oxidase 4 (NOX4) in both human HaCaT keratinocytes and mouse dorsal skin and explore its cytoprotective mechanism. The mechanism of action was determined using western blotting, immunocytochemistry, NADP+/NADPH assay, reactive oxygen species (ROS) detection, and cell viability assay. THB attenuated UVB-induced NOX4 expression both in vitro and in vivo, and suppressed UVB-induced ROS generation via NADP+ production, resulting in increased cell viability with decreased apoptosis. THB also reduced the expression of UVB-induced phosphorylated AMP-activated protein kinase (AMPK) and phosphorylated c-Jun N-terminal kinase (JNK). THB suppressed UVB-induced NOX4 expression and ROS generation by inhibiting AMPK and JNK signaling pathways, thereby inhibiting cellular damage. These results showed that THB could be developed as a UV protectant.

Advanced oxidation of Arsenic(III) to Arsenic(V) using ozone nanobubbles under high salinity

Arsenic, a highly toxic element, is present in various water resources as As(III) and/or As(V). The removal of As(V) using adsorption is considered to be easier than the removal of As(III). In this work, we report the oxidation of As(III) to As(V) using ozone nanobubbles. Ozone has been widely used in the advanced oxidation process (AOP) to remove organics and inorganics in wastewater. The major advantage of ozone nanobubbles is their enhanced half-life, which leads to higher ozone solubility in water. In addition, the rate of mass transfer by using nanobubbles can be enhanced drastically. The effect of ozone flow rates, initial As(III) concentrations, pH levels, and the presence of salt is systematically studied in this work. The present results revealed that ozone nanobubbles positively impacted the oxidation of As(III) to As(V). AOP process based on O3 NBs (nanobubbles) was most efficient with 99 % oxidation rates of 1 ppm of As(III) within 20 minutes at 6.5 ppm ozone concentrations. An acidic pH of 3–7 promoted quick oxidation due to the high mass transfer coefficient of ozone nanobubbles. About ∼70 % degradation of As(III) to As(V) was achieved with 0.10854 min-1 rate constant at acidic (pH = 3) compared to ∼39 % degradation with 0.046 min-1 rate constant at pH =11. The presence of salt (∼50 mM) in the solution not only hindered the ozone mass transfer coefficient but also reduced the stability of nanobubbles. The detection of reactive oxygen species, particularly hydroxyl radical was unravelled by utilizing 2-propanol as a scavenger.

Screening and Mechanism Study of Three Antagonistic Drugs, Oxysophoridine, Rutin, and Phellodendrine, against Zearalenone-Induced Reproductive Toxicity in Ovine Oocytes.

Zearalenone (ZEN) is a common fungal toxin with reproductive toxicity in various grains. It poses a serious threat to ovine and other animal husbandry industries, as well as human reproductive health. Therefore, investigating the mechanism of toxicity and screening antagonistic drugs are of great importance. In this study, based on the natural compound library and previous Smart-seq2 results, antioxidant and anti-apoptotic drugs were selected for screening as potential antagonistic drugs. Three natural plant compounds (oxysophoridine, rutin, and phellodendrine) were screened for their ability to counteract the reproductive toxicity of ZEN on ovine oocytes in vitro using quantitative polymerase chain reaction (qPCR) and reactive oxygen species detection. The compounds exhibited varying pharmacological effects, notably impacting the expression of antioxidant (GPX, SOD1, and SOD2), autophagic (ATG3, ULK2, and LC3), and apoptotic (CAS3, CAS8, and CAS9) genes. Oxysophoridine promoted GPX, SOD1, ULK2, and LC3 expression, while inhibiting CAS3 and CAS8 expression. Rutin promoted SOD2 and ATG3 expression, and inhibited CAS3 and CAS9 expression. Phellodendrine promoted SOD2 and ATG3 expression, and inhibited CAS9 expression. However, all compounds promoted the expression of genes related to cell cycle, spindle checkpoint, oocyte maturation, and cumulus expansion factors. Although the three drugs had different regulatory mechanisms in enhancing antioxidant capacity, enhancing autophagy, and inhibiting cell apoptosis, they all maintained a stable intracellular environment and a normal cell cycle, promoted oocyte maturation and release of cumulus expansion factors, and, ultimately, counteracted ZEN reproductive toxicity to promote the in vitro maturation of ovine oocytes. This study identified three drugs that antagonize the reproductive toxicity of ZEN on ovine oocytes, and compared their mechanisms of action, providing data support and a theoretical basis for their subsequent application in the ovine breeding industry, reducing losses in the breeding industry, screening of ZEN reproductive toxicity antagonists and various toxin antagonists, improving the study of ZEN reproductive toxicity mechanisms, and even protection of human reproductive health.

Salidroside Inhibits α-Amanitin-Induced AML-12 Cell Apoptosis via the Regulation of PINK1/Parkin-Mediated Mitophagy and Mitochondrial Function.

Poisoning caused by the mushroom Amanita phalloides, due to the toxin α-amanitin, accounts for approximately 90% of food poisoning deaths in China with no specific antidotes. To investigate the role of salidroside (Sal) in α-amanitin (α-AMA)-induced mitophagy, mouse liver cells AML-12 were exposed to α-AMA in the presence of Sal or not. Intracellular reactive oxygen species (ROS) levels were measured using a ROS detection kit, mitochondrial activity was evaluated using a mitochondrial red fluorescent probe kit or JC-1 dye, and protein expression levels of PINK1, Parkin, LC3 II, P62, Bax, Bcl-2, Caspase 3, Cleaved-Caspase 3, PARP I, and Cleaved-PARP I were detected through Western blot. Results demonstrated that α-AMA led to increased intracellular ROS levels, cell apoptosis, and decreased mitochondrial membrane potential. Notably, expression levels of mitophagy-related proteins PINK1, Parkin, and LC3 increased significantly while the P62 protein expression decreased remarkably. Furthermore, Sal reversed the α-AMA-induced decrease in cell viability and mitochondrial membrane potential and increase in intracellular ROS level. In addition, Sal promoted expression levels of PINK1, Parkin, and LC3 II while suppressing the Bax/Bcl-2 ratio, Cleaved-Caspase 3, and Cleaved-PARP I as well as P62. The results above proved that salidroside alleviates α-AMA-induced mouse liver cells damage via promoting PINK1/Parkin-mediated mitophagy and reducing cell apoptosis.

Iron efflux by IetA enhances β-lactam aztreonam resistance and is linked to oxidative stress through cellular respiration in Riemerella anatipestifer.

Riemerella anatipestifer encodes an iron acquisition system, but whether it encodes the iron efflux pump and its role in antibiotic resistance are largely unknown. To screen and identify an iron efflux gene in R. anatipestifer and determine whether and how the iron efflux gene is involved in antibiotic resistance. In this study, gene knockout, streptonigrin susceptibility assay and inductively coupled plasma mass spectrometry were used to screen for the iron efflux gene ietA. The MIC measurements, scanning electron microscopy and reactive oxygen species (ROS) detection were used to verify the role of IetA in aztreonam resistance and its mechanism. Mortality and colonization assay were used to investigate the role of IetA in virulence. The deletion mutant ΔietA showed heightened susceptibility to streptonigrin, and prominent intracellular iron accumulation was observed in ΔfurΔietA under excess iron conditions. Additionally, ΔietA exhibited increased sensitivity to H2O2-produced oxidative stress. Under aerobic conditions with abundant iron, ΔietA displayed increased susceptibility to the β-lactam antibiotic aztreonam due to heightened ROS production. However, the killing efficacy of aztreonam was diminished in both WT and ΔietA under anaerobic or iron restriction conditions. Further experiments demonstrated that the efficiency of aztreonam against ΔietA was dependent on respiratory complexes Ⅰ and Ⅱ. Finally, in a duckling model, ΔietA had reduced virulence compared with the WT. Iron efflux is critical to alleviate oxidative stress damage and β-lactam aztreonam killing in R. anatipestifer, which is linked by cellular respiration.