ZLN005 alleviates PBDE-47 induced impairment of mitochondrial translation and neurotoxicity through PGC-1α/ERRα axis.

Recent studies are identified the mitochondria as critical targets of 2, 2', 4, 4'-tetrabromodiphenyl ether (PBDE-47) induced neurotoxicity. This study aimed at examining the impact of PBDE-47 exposure on mitochondrial translation, and its subsequent effect on PBDE-47 neurotoxicity. The Sprague-Dawley (SD) rat model and neuroendocrine pheochromocytoma (PC12) cells were adopted for the measurements of mitochondrial ATP levels, mitochondrial translation products, and expressions of important mitochondrial regulators, such as required meiotic nuclear division 1 (RMND1), estrogen-related receptor α (ERRα), and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α). To delve into the role of PGC-1α/ERRα axis in mitochondrial translation, 2-(4-tert-butylphenyl) benzimidazole (ZLN005) was employed. Both cellular and animal model results shown that PBDE-47 impeded PGC-1α/ERRα axis and mitochondrial translation. PBDE-47 suppressed mitochondrial function in rat hippocampus and PC12 cells by decreasing relative mitochondrial DNA (mtDNA) content, mitochondrial translation products, and mitochondrial ATP levels. Particularly, ZLN005 reversed PBDE-47 neurotoxicity by enhancing mitochondrial translation through activation of PGC-1α/ERRα axis, yet suppressing PGC-1α with siRNA attenuates its neuroprotective effect in vitro. In conclusion, this work highlights the importance of mitochondrial translation in PBDE-47 neurotoxicity by presenting results from cellular and animal models and suggests a potential therapeutic approach through activation of PGC-1α/ERRα axis. ENVIRONMENTAL IMPLICATION: PBDEs have attracted extensive attention because of their high lipophilicity, persistence, and detection levels in various environmental media. Increasing evidence has shown that neurodevelopmental disorders in children are associated with PBDE exposure. Several studies have also found that perinatal PBDE exposure can cause long-lasting neurobehavioral abnormalities in experimental animals. Our recent studies have also demonstrated the impact of PBDE-47 exposure on mitochondrial biogenesis and dynamics, leading to memory and neurobehavioral deficits. Therefore, we explore whether the pathological mechanism of PBDE-47-induced neurotoxicity involves the regulation of mitochondrial translation through the PGC-1α/ERRα axis.

Exosomal Tenascin-C primes macrophage pyroptosis amplifying aberrant inflammation during sepsis-induced acute lung injury.

Sepsis-induced acute lung injury (ALI) is a serious complication of sepsis and the predominant cause of death. Exosomes released by lung tissue cells critically influence the progression of ALI during sepsis by modulating the inflammatory microenvironment. However, the molecular mechanisms by which exosome-mediated intercellular signaling exacerbates ALI in septic infection remain undefined. Our study found increased levels of exosomal Tenascin-C (TNC) in the plasma of both patients and mice with ALI, showing a strong association with disease progression. By integrating exosomal proteomics with transcriptome sequencing and experimental validation, we elucidated that LPS induce unresolved endoplasmic reticulum stress (ERs) in alveolar epithelial cells (AECs), ultimately leading to the release of exosomal TNC through the activation of PERK-eIF2α and the transcription factor CHOP. In the sepsis mouse model with TNC knockout, we noted a marked reduction in macrophage pyroptosis. Our detailed investigations found that exosomal TNC binds to TLR4 on macrophages, resulting in an augmented production of ROS, subsequent mitochondrial damage, activation of the NF-κB signaling pathway, and induction of DNA damage response. These interconnected events culminate in macrophage pyroptosis, thereby amplifying the release of inflammatory cytokines. Our findings demonstrate that exosomal Tenascin-C, released from AECs under unresolved ER stress, exacerbates acute lung injury by intensifying sepsis-associated inflammatory responses. This research provides new insights into the complex cellular interactions underlying sepsis-induced ALI.

The role of mTORC1/TFEB axis mediated lysosomal biogenesis and autophagy impairment in fluoride neurotoxicity and the intervention effects of resveratrol.

Elevated exposures to fluoride have been linked to neurological diseases. Identifying mechanisms of fluoride neurotoxicity and finding ways for prevention and treatment of epidemic fluorosis are important issues of public health. In this study, fluoride inhibited TFEB nuclear translocation by activating p-mTORC1/p-p70S6K, thus inhibiting lysosomal biogenesis, leading to dysfunctional lysosome accumulation, which further negatively affected autophagosome and lysosome fusion, thus impairing autophagy degradation, evidenced by the blocked conversion of LC3II to LC3I, and the increased p62 levels. Interestingly, RSV alleviated rats' cognition by improving fluoride-induced nerve damage and promoted lysosomal biogenesis demonstrated by the increased nucleus translocation of TFEB via inhibiting p-mTORC1 and p-p70S6K, the decreased expression of LC3II and p62. Collectively, we clarified the correlation between fluoride neurotoxicity and mTORC1/TFEB-mediated lysosomal biogenesis and autophagy. Meanwhile, RSV appeared to be a promising drug for the prevention and treatment of epidemic fluorosis.

Organic Electrochemical Transistors for Biomarker Detections.

The improvement of living standards and the advancement of medical technology have led to an increased focus on health among individuals. Detections of biomarkers are feasible approaches to obtaining information about health status, disease progression, and response to treatment of an individual. In recent years, organic electrochemical transistors (OECTs) have demonstrated high electrical performances and effectiveness in detecting various types of biomarkers. This review provides an overview of the working principles of OECTs and their performance in detecting multiple types of biomarkers, with a focus on the recent advances and representative applications of OECTs in wearable and implantable biomarker detections, and provides a perspective for the future development of OECT-based biomarker sensors.

MOFs-Based Nanoagents Enable Sequential Damage to Cancer-Associated Fibroblast and Tumor Cells for Phototriggered Tumor Microenvironment Regulation.

A composite nanoagent capable of phototriggered tumor microenvironment (TME) regulation is developed based on copper (II) metal-organic frameworks (MOFs) with encapsulation of blebbistatin (Bb) and surface modification of fibroblast activation protein-αtargeted peptide (Tp). Tp enables active targeting of the nanoagents to cancer-associated fibroblast (CAF) while near-infrared light triggers Cu2+ -to-Cu+ photoreduction in MOFs, which brings about the collapse of MOFs and the release of Bb and Cu+ . Bb mediates photogeneration of hydroxyl radicals (•OH) and therefore inhibits extracellular matrix production by inducing CAF apoptosis, which facilitates the penetration of nanoagent to deep tumor tissue. The dual-channel generation of •OH based on Bb and the Cu+ species, via distinct mechanisms, synergistically reinforces oxidative stress in TME capable of inducing immunogenic cell death, which activates the antitumor immune response and therefore reverses the immunosuppressive TME. The synergistic antitumor phototherapy efficacy of such a type of nanoagent based on the abovementioned TME remodeling is unequivocally verified in a cell-derived tumor xenograft model.

SIRT1, a target of miR-708-3p, alleviates fluoride-induced neuronal damage via remodeling mitochondrial network dynamics.

INTRODUCTION: Neurological dysfunction induced by fluoride contamination is still one of major concern worldwide. Recently, neuroprotective roles of silent information regulator 1 (SIRT1) focusing on mitochondrial function have been highlighted. However, what roles SIRT1 exerts and the underlying regulative mechanisms, remain largely uncharacterized in such neurotoxic process of fluoride. OBJECTIVES: We aimed at evaluating the regulatory roles of SIRT1 in human neuroblastoma SH-SY5Y cells and Sprague-Dawley rats with fluoride treatment, and to further identify potential miRNA directly targeting SIRT1. METHODS: Pharmacological suppression of SIRT1 by nicotinamide (NIC) and promotion of SIRT1 by adenovirus (Ad-SIRT1) or resveratrol (RSV) were employed to assess the effects of SIRT1 in mitochondrial dysfunction induced by fluoride. Also, miRNAs profiling and bioinformatic prediction were used to screen the miRNAs which can regulate SIRT1 directly. Further, chemical mimic or inhibitor of chosen miRNA was applied to validate the modulation of chosen miRNA. RESULTS: NIC exacerbated defects in mitochondrial network dynamics and cytochrome c (Cyto C) release-driven apoptosis, contributing to fluoride-induced neuronal death. In contrast, the ameliorative effects were observed when overexpressing SIRT1 by Ad-SIRT1 in vitro or RSV in vivo. More importantly, miR-708-3p targeting SIRT1 directly was identified. And interestingly, moreover, treatment with chemically modified miR-708-3p mimic aggravated, while miR-708-3p inhibitor suppressed fluoride-caused neuronal death. Further confirmedly, overexpressing SIRT1 effectively neutralized miR-708-3p mimic-worsened fluoride neuronal death via correcting mitochondrial network dynamics. On contrary, inhibiting SIRT1 counteracted the promotive effects of miR-708-3p inhibitor against neurotoxic response by fluoride through aggravating abnormal mitochondrial network dynamics. CONCLUSION: These data underscore the functional importance of SIRT1 to mitochondrial network dynamics in neurotoxic process of fluoride and further screen a novel unreported neuronal function of miR-708-3p as an upstream regulator of targeting SIRT1, which has important theoretical implications for a potential therapeutic and preventative target for treatment of neurotoxic progression by fluoride.

Enabling Quick Response to Nitrogen Dioxide at Room Temperature and Limit of Detection to Ppb Level by Heavily n-Doped Graphene Hybrid Transistor.

Sensitive detection of nitrogen dioxide (NO2) is of significance in many areas for health and environmental protections. In this work, we developed an efficient NO2 sensor that can respond within seconds at room temperature, and the limit of detection (LOD) is as low as 100 ppb. Coating cyano-substituted poly(p-phenylene vinylene) (CN-PPV) films on graphene (G) layers can dope G sheets effectively to a heavy n state. The influences of solution concentrations and annealing temperatures on the n-doping effect were investigated in detail. The CN-PPV-G transistors fabricated with the optimized parameters demonstrate active sensing abilities toward NO2. The n-doping state of CN-PPV-G is reduced dramatically by NO2, which is a strong p-doping compound. Upon exposure to 25 ppm of NO2, our CN-PPV-G sensors react in 10 s, indicating it is almost an immediate response. LOD is determined as low as 100 ppb. The ultrahigh responding speed and low LOD are not affected in dry air. Furthermore, cycling use of our sensors can be realized through simple annealing. The superior features shown by our CN-PPV-G sensors are highly desired in the applications of monitoring the level of NO2 in situ and setting immediate alarms. Our results also suggest that transfer curves of transistors can react very promptly to the stimulus of target gas and, thus, are very promising in the development of fast-response sensing devices although the response values may not reach maximum as a tradeoff.

Generation of whole tumor cell vaccine for on-demand manipulation of immune responses against cancer under near-infrared laser irradiation.

The therapeutic efficacy of whole tumor cell vaccines (TCVs) is modest, which has delayed their translation into personalized immunotherapies in the clinic. Here, we develop a TCV platform based on photothermal nanoparticle-loaded tumor cells, which can be rationally applied to diverse tumor types to achieve on-demand boost of anti-tumor immune responses for inhibiting tumor growth. During the fabrication process, mild photothermal heating by near-infrared (NIR) laser irradiation induces the nanoparticle-bearing tumor cells to express heat shock proteins as endogenous adjuvants. After a single vaccination at the back of tumor-bearing mice, non-invasive NIR laser irradiation further induces mild hyperthermia at vaccination site, which promotes the recruitment, activation, and antigen presentation by dendritic cells. Using an indicator we term fluctuation of tumor growth rate, we determine appropriate irradiation regimens (including optimized irradiation intervals and times). This TCV platform enables on-demand NIR manipulation of immune responses, and we demonstrate potent therapeutic efficacy against six murine models that mimick a range of clinical scenarios, including a model based on humanized mice and patient-derived tumor xenografts.

Photoisomerization-controlled wavelength-tunable plasmonic lasers.

We demonstrate photoisomerization-controlled wavelength-tunable plasmonic lasers by integrating spiropyran derivative-doped PMMA films with two-dimensional Ag nanoparticle arrays. The controllable transformation between spiropyran derivatives and its isomers with different refractive indices by photoexcitation allows for a dynamical and continuous change of the refractive index in the host PMMA film, which is able to tune the lattice plasmon resonance, and hence the lasing wavelength. This result opens up a new avenue for engineering wavelength tunable plasmonic lasers toward practical photonic integration.

Correction: Noncovalent wedging effect catalyzed the cis to syn transformation of a surface-adsorbed polymer backbone toward an unusual thermodynamically stable supramolecular product.

Correction for 'Noncovalent wedging effect catalyzed the cis to syn transformation of a surface-adsorbed polymer backbone toward an unusual thermodynamically stable supramolecular product' by Zhi-Xuan Liu et al., Phys. Chem. Chem. Phys., 2022, 24, 30010-30016, https://doi.org/10.1039/D2CP04184G.

Fluoride impairs mitochondrial translation by targeting miR-221-3p/c-Fos/RMND1 axis contributing to neurodevelopment defects.

Evidence suggests that fluoride-induced neurodevelopment damage is linked to mitochondrial disorder, yet the detailed mechanism remains unclear. A cohort of Sprague-Dawley rats developmentally exposed to sodium fluoride (NaF) was established to simulate actual exposure of human beings. Using high-input proteomics and small RNA sequencing technology in rat hippocampus, we found mitochondrial translation as the most striking enriched biological process after NaF treatment, which involves the differentially expressed Required Meiotic Nuclear Division 1 homolog (RMND1) and neural-specific miR-221-3p. Further experiments in vivo and in vitro neuroendocrine pheochromocytoma (PC12) cells demonstrated that NaF impaired mitochondrial translation and function, as shown by declined mitochondrial membrane potential and inhibited expression of mitochondrial translation factors, mitochondrial translation products, and OXPHOS complexes, which was concomitant with decreased RMND1 and transcription factor c-Fos in mRNA and proteins as well as elevated miR-221-3p. Notably, RMND1 overexpression alleviated the NaF-elicited mitochondrial translation impairment by up-regulating translation factors, but not vice versa. Interestingly, ChIP-qPCR confirmed that c-Fos specifically controls the RMND1 transcription through direct binding with Rmnd1 promotor. Interference of gene expression verified c-Fos as an upstream positive regulator of RMND1, implicating in fluoride-caused mitochondrial translation impairment. Furthermore, dual-luciferase reporter assay evidenced that miR-221-3p targets c-Fos by binding its 3' untranslated region. By modulating the miR-221-3p expression, we identified miR-221-3p as a critical negative regulator of c-Fos. More importantly, we proved that miR-221-3p inhibitor improved mitochondrial translation and mitochondrial function to combat NaF neurotoxicity via activating the c-Fos/RMND1 axis, whereas miR-221-3p mimic tended towards opposite effects. Collectively, our data suggest fluoride impairs mitochondrial translation by dysregulating the miR-221-3p/c-Fos/RMND1 axis to trigger mitochondrial dysfunction, leading to neuronal death and neurodevelopment defects.

Composite Mesoporous Silica Nanoparticles with Dual-color Afterglow for Cross-correlation-based Living Cell Imaging.

Room temperature phosphorescence (RTP) materials are characterized with emission after removing the excitation source. Such long-lived emission feature possesses great potential in biological fluorescence imaging because it enables a way regarding temporal dimension for separating the interference of autofluorescence and common noises typically encountered in conventional fluorescence imaging. Herein, we constructed a new type of mesoporous silica nanoparticles (MSNs)-based composite nanoparticles (NPs) with dual-color long-lived emission, namely millisecond-level green phosphorescence and sub-millisecond-level delayed red fluorescence by encapsulating a typical RTP dye and Rhodamine dye in the cavities of the MSNs with the former acting as energy donor (D) while the latter as acceptor (A). Benefiting from the close D-A proximity, energy match between the donor and the acceptor and the optimized D/A ratio in the composite NPs, efficient triplet-to-singlet Förster resonance energy transfer (TS-FRET) in the NPs occurred upon exciting the donor, which enabled dual-color long-lived emission. The preliminary results of dual-color correlation imaging of live cells based on such emission feature unequivocally verified the unique ability of such NPs for distinguishing the false positive generated by common emitters with single-color emission feature.

PBDE-47 induces impairment of mitochondrial biogenesis and subsequent neurotoxicity through miR-128-3p/PGC-1α axis.

The potential adverse effects of 2,2',4,4'-tetrabromodiphenyl ether (PBDE-47) on neurons are extensively studied, and mitochondria are identified as critical targets. This study aimed to investigate whether PBDE-47 impairs mitochondrial biogenesis via the miR-128-3p/PGC-1α axis to trigger mitochondrial dysfunction-related neuronal damage. In vitro neuroendocrine pheochromocytoma (PC12) cells and in vivo Sprague Dawley rat model were adopted. In this study, biochemical methods were used to examine mitochondrial ATP content, cell viability, and expressions of key mitochondrial biogenesis regulators, including peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), nuclear respiratory factor 1 (NRF1), and mitochondrial transcription factor A (TFAM). Mimics and inhibitors of miR-128-3p were employed to explore its role in PBDE-47-induced neurotoxicity. Both in vivo and in vitro evidences suggested that PBDE-47 suppressed PGC-1α/NRF1/TFAM signaling pathways and mitochondrial DNA (mtDNA) encoding proteins synthesis. PBDE-47 also suppressed the relative mtDNA content, mRNA levels of mtDNA-encoded subunits, and mitochondrial ATP levels in vitro. Specifically, 2-(4-tert-butylphenyl) benzimidazole (ZLN005) alleviated PBDE-47-induced neuronal death through the improvement of mitochondrial function by activating PGC-1α/NRF1/TFAM signaling pathways. Mechanistically, PBDE-47 dramatically upregulated miR-128-3p expression. Furthermore, miR-128-3p inhibition enhanced PGC-1α/NRF1/TFAM signaling and abolished PBDE-47-induced impairment of mitochondrial biogenesis. In summary, this study provides in vitro evidence to reveal the role of mitochondrial biogenesis in PBDE-47-induced mitochondrial dysfunction and related neurotoxicity and suggests that miR-128-3p/PGC-1α axis may be a therapeutic target for PBDE-47 neurotoxicity.

Noncovalent wedging effect catalyzed the cis to syn transformation of a surface-adsorbed polymer backbone toward an unusual thermodynamically stable supramolecular product.

The significant influence of noncovalent interactions on catalytic processes has been recently appreciated but is still in its infancy. In this report, it is found that wedging Me-PTCDI (small-molecule) between the alkyl chains of PffBT4T-2OD (polymer) and a graphite substrate can reduce the energy barrier of flipping over the surface-adsorbed alkylthiophene group from the cis to syn conformation, revealing the catalytic role of Me-PTCDI via a noncovalent wedging effect. The wedging of Me-PTCDI brings the interactions between the alkyl chains and substrate to a very weak level by lifting up the alkyl chains, which eliminates the major hindrance of the flipping process to one main factor: the torsion of the dihedral angles of the thiophene group. The Me-PTCDI/syn PffBT4T-2OD arrangement shows unusual stability compared to the cis one because the syn conformation allows the alkyl chains to construct dense lamella and facilitates interactions between Me-PTCDI and the syn PffBT4T-2OD backbones. The results are helpful for boosting the development of noncovalent catalysis and bottom-up fabrications toward devices functionalized at a molecular level.

Characterization and correlation of bacterial community and volatile flavor compounds in xiguajiang, a Chinese traditional fermented condiment.

Xiguajiang (XGJ) is one kind of Chinese traditionally fermented soybean food. The aim of this study was to identify core bacterial communities and volatile compounds and explore their relationships in XGJ samples obtained from different manufacturers. Results showed that Bacillus, Staphylococcus, Weissella, and Chromohalobacter were the predominant bacterial genus, although their relative abundance is quite diverse. Larger relative contents of esters and alcohols were detected in XGJ. Moreover, the results of E-nose analysis indicated that nitrogen oxides compounds, pyrazines, and ketones compounds also played a critical role in XGJ unique flavor. The correlation analysis suggested that 3-methyl-butanol, ethoxybenzene, ethyl acetate, acetaldehyde, and 2-(4-methyl-3-cyclohexen-1-yl)-2-propanyl acetate had a significant correlation with Enterobacter, Clostridium, Pseudomonas, Streptomyces, Weissella, Staphylococcus, and Bacillus. These results may provide vital information to understand the role of the microbiota in developing flavor in XGJ products, and improve the quality and safety of XGJ production in industries.

Identification of immune-related endoplasmic reticulum stress genes in sepsis using bioinformatics and machine learning.

Background: Sepsis-induced apoptosis of immune cells leads to widespread depletion of key immune effector cells. Endoplasmic reticulum (ER) stress has been implicated in the apoptotic pathway, although little is known regarding its role in sepsis-related immune cell apoptosis. The aim of this study was to develop an ER stress-related prognostic and diagnostic signature for sepsis through bioinformatics and machine learning algorithms on the basis of the differentially expressed genes (DEGs) between healthy controls and sepsis patients. Methods: The transcriptomic datasets that include gene expression profiles of sepsis patients and healthy controls were downloaded from the GEO database. The immune-related endoplasmic reticulum stress hub genes associated with sepsis patients were identified using the new comprehensive machine learning algorithm and bioinformatics analysis which includes functional enrichment analyses, consensus clustering, weighted gene coexpression network analysis (WGCNA), and protein-protein interaction (PPI) network construction. Next, the diagnostic model was established by logistic regression and the molecular subtypes of sepsis were obtained based on the significant DEGs. Finally, the potential diagnostic markers of sepsis were screened among the significant DEGs, and validated in multiple datasets. Results: Significant differences in the type and abundance of infiltrating immune cell populations were observed between the healthy control and sepsis patients. The immune-related ER stress genes achieved strong stability and high accuracy in predicting sepsis patients. 10 genes were screened as potential diagnostic markers for sepsis among the significant DEGs, and were further validated in multiple datasets. In addition, higher expression levels of SCAMP5 mRNA and protein were observed in PBMCs isolated from sepsis patients than healthy donors (n = 5). Conclusions: We established a stable and accurate signature to evaluate the diagnosis of sepsis based on the machine learning algorithms and bioinformatics. SCAMP5 was preliminarily identified as a diagnostic marker of sepsis that may affect its progression by regulating ER stress.

Polymeric micelle-based nanoagents enable phototriggering combined chemotherapy and photothermal therapy with high sensitivity.

A new type of polymeric nanomicelle-based nanoagent (denoted as PT@MFH hereafter) capable of the highly sensitive release of the chemotherapeutic drug paclitaxel (PTX) upon exposure to a near-infrared (NIR) laser trigger was developed. Specifically, PTX and a photothermal polymer (T-DPPT) were encapsulated in the cavity of nanomicelles, which were constructed from an amphiphilic block copolymer (PCL-PEEP) with a lower critical solution temperature (LCST) of ∼54 °C. Owing to the unprecedented ability of the T-DPPT moiety to harvest near-infrared light, with a mass extinction coefficient at 808 nm of up to ∼80.8 L g-1 cm-1, and convert NIR light to heat, with a photothermal conversion efficiency (η) of up to ∼70%, local hyperthermia was promptly realized via irradiation from an 808 nm laser with extraordinarily low output power. This enabled remarkable contrast in the local temperature and drug release between the "silent" state (prior to phototriggering) and the "activated" state (after phototriggering). This NIR-light-activated local hyperthermia and drug release presented the basis for combined chemotherapy and photothermal therapy (PTT) in antitumor treatment and displayed superb therapeutic efficacy. This pattern together with the high spatial precision imparted by laser triggering jointly contributed to the maximum combined antitumor efficacy to the tumor, while exhibiting minimal side effects on the normal tissues, as preliminarily verified in the in vivo experiment regarding the ability of PT@MFH to efficiently inhibit tumor growth in tumor-bearing model mice.

Microenvironment Regulation of {Co4IIO4} Cubane for Syngas Photosynthesis.

It is a great challenging task for selectivity control of both CO2 photoreduction and water splitting to produce syngas via precise microenvironment regulation. Herein, a series of UiO-type Eu-MOFs (Eu-bpdc, Eu-bpydc, Rux-Eu-bpdc, and Rux-Eu-bpydc) with different surrounding confined spaces were designed and synthesized. These photosensitizing Rux-Eu-MOFs were used as the molecular platform to encapsulate the [CoII4(dpy{OH}O)4(OAc)2(H2O)2]2+ (Co4) cubane cluster for constructing Co4@Rux-Eu-MOF (x = 0.1, 0.2, and 0.4) heterogeneous photocatalysts for efficient CO2 photoreduction and water splitting. The H2 and CO yields can reach 446.6 and 459.8 µmol·g-1, respectively, in 10 h with Co4@Ru0.1-Eu-bpdc as the catalyst, and their total yield can be dramatically improved to 2500 µmol·g-1 with the ratio of CO/H2 ranging from 1:1 to 1:2 via changing the photosensitizer content in the confined space. By increasing the N content around the cubane, the photocatalytic performance drops sharply in Co4@Ru0.1-Eu-bpydc, but with an enhanced proportion of CO in the final products. In the homogeneous system, the Co4 cubane was surrounding with Ru photosensitizers via week interactions, which can drive water splitting into H2 with >99% selectivity. Comprehensive structure-function analysis highlights the important role of microenvironment regulation in the selectivity control via constructing homogeneous and heterogeneous photocatalytic systems. This work provides a new insight for engineering a catalytic microenvironment of the cubane cluster for selectivity control of CO2 photoreduction and water splitting.

TFEB ameliorates autophagy flux disturbance induced by PBDE-47 via up-regulating autophagy-lysosome fusion.

2,2',4,4'-tetrabromodiphenyl ether (PBDE-47), the widely used brominated flame retardant, has remarkable neurotoxicity which is associated with autophagy disorder. However, the mechanism remains unclear. The results showed that PBDE-47 damaged lysosomal biogenesis and interfered with autophagy-lysosome fusion both in vivo and in vitro. Our investigation further demonstrated that PBDE-47 could downregulate TFEB expression and inhibit the nuclear translocation of TFEB. Knockdown of TFEB in PC12 cells increased the reduction of lysosomal-associated proteins and the expression of STX17-SNAP29-VAMP8 proteins involved in autophagy-lysosomal fusion. Conversely, Overexpression TFEB in vitro significantly improved lysosomal abundance and ameliorated the autophagosome-lysosome fusion inhibition, thus restoring autophagic flux and improving PC12 cells survival. In addition, TFEB biologically interacted with STX17 by not inducing or inducing TFEB overexpression. Collectively, our results indicate that the autophagy flux compromised by PBDE-47 is related to the defective fusion of autophagosome and lysosome. TFEB may serve as a promising molecular target for future study of PBDE-47 developmental neurotoxicity.

MOFs-based nanoagent enables dual mitochondrial damage in synergistic antitumor therapy via oxidative stress and calcium overload.

Targeting subcellular organelle with multilevel damage has shown great promise for antitumor therapy. Here, we report a core-shell type of nanoagent with iron (III) carboxylate metal-organic frameworks (MOFs) as shell while upconversion nanoparticles (UCNPs) as core, which enables near-infrared (NIR) light-triggered synergistically reinforced oxidative stress and calcium overload to mitochondria. The folate decoration on MOFs shells enables efficient cellular uptake of nanoagents. Based on the upconversion ability of UCNPs, NIR light mediates Fe3+-to-Fe2+ reduction and simultaneously activates the photoacid generator (pHP) encapsulated in MOFs cavities, which enables release of free Fe2+ and acidification of intracellular microenvironment, respectively. The overexpressed H2O2 in mitochondria, highly reactive Fe2+ and acidic milieu synergistically reinforce Fenton reactions for producing lethal hydroxyl radicals (•OH) while plasma photoacidification inducing calcium influx, leading to mitochondria calcium overload. The dual-mitochondria-damage-based therapeutic potency of the nanoagent has been unequivocally confirmed in cell- and patient-derived tumor xenograft models in vivo.