A Novel Needle Mouse Model of Vascular Cognitive Impairment and Dementia.

Bilateral common carotid artery (CCA) stenosis (BCAS) is a useful model to mimic vascular cognitive impairment and dementia (VCID). However, current BCAS models have the disadvantages of high cost and incompatibility with magnetic resonance imaging (MRI) scanning because of metal implantation. We have established a new low-cost VCID model that better mimics human VCID and is compatible with live-animal MRI. The right and the left CCAs were temporarily ligated to 32- and 34-gauge needles with three ligations, respectively. After needle removal, CCA blood flow, cerebral blood flow, white matter injury (WMI) and cognitive function were measured. In male mice, needle removal led to ∼49.8% and ∼28.2% blood flow recovery in the right and left CCA, respectively. This model caused persistent and long-term cerebral hypoperfusion in both hemispheres (more severe in the left hemisphere), and WMI and cognitive dysfunction in ∼90% of mice, which is more reliable compared with other models. Importantly, these pathologic changes and cognitive impairments lasted for up to 24 weeks after surgery. The survival rate over 24 weeks was 81.6%. Female mice showed similar cognitive dysfunction, but a higher survival rate (91.6%) and relatively milder white matter injury. A novel, low-cost VCID model compatible with live-animal MRI with long-term outcomes was established.SIGNIFICANCE STATEMENT Bilateral common carotid artery (CCA) stenosis (BCAS) is an animal model mimicking carotid artery stenosis to study vascular cognitive impairment and dementia (VCID). However, current BCAS models have the disadvantages of high cost and incompatibility with magnetic resonance imaging (MRI) scanning due to metal implantation. We established a new asymmetric BCAS model by ligating the CCA to various needle gauges followed by an immediate needle removal. Needle removal led to moderate stenosis in the right CCA and severe stenosis in the left CCA. This needle model replicates the hallmarks of VCID well in ∼90% of mice, which is more reliable compared with other models, has ultra-low cost, and is compatible with MRI scanning in live animals. It will provide a new valuable tool and offer new insights for VCID research.

Tumor suppressive function of IGF2BP1 in gastric cancer through decreasing MYC.

Gastric cancer is one of the most common causes of cancer-related death worldwide. The N6 -methyladenosine (m6 A) reader IGF2BP1 (insulin-like growth factor-2 mRNA binding protein 1) has been reported to promote cancer progression by stabilizing oncogenic mRNAs through its m6 A-binding activity in some tumors. However, the role of IGF2BP1 in gastric carcinogenesis remains unclear. In this study, we found that IGF2BP1 is significantly downregulated in tumor tissues from patients with gastric cancer. Lower expression of IGF2BP1 is associated with poor prognosis. Gastric cancer cell proliferation is suppressed by IGF2BP1 in an m6 A-dependent manner. Additionally, IGF2BP1 is able to significantly attenuate tumor growth of gastric cancer cells. Further m6 A sequencing and m6 A-RNA immunoprecipitation assays show that MYC (c-myc proto-oncogene) mRNA is a target transcript of IGF2BP1 in gastric cancer cells. IGF2BP1 inhibits gastric cancer cell proliferation by reducing the mRNA and protein expression of MYC. Mechanistically, IGF2BP1 promotes the degradation of MYC mRNA and inhibits its translation efficiency. Taken together, these data suggest that IGF2BP1 plays a tumor-suppressive role in gastric carcinogenesis by downregulating MYC in an m6 A-dependent manner, thereby making the IGF2BP1-MYC axis a potential target for gastric cancer treatment.

Mass-Spectrometry-Based Assay at Single-Base Resolution for Simultaneously Detecting m6A and m6Am in RNA.

The methylation modifications of adenosine, especially N6-methyladenosine (m6A) and N6, 2'-odimethyladenosine (m6Am), play vital roles in various biological, physiological, and pathological processes. However, current methods for detecting these modifications at single-base resolution have limitations. Mass spectrometry (MS), a highly accurate and sensitive technique, can be utilized to differentiate between m6A and m6Am by analyzing the molecular weight differences in their fragments during tandem MS analysis. In this study, we present an MS-based method that allows for the simultaneous determination of m6A and m6Am sites in targeted RNA fragments at single-nucleotide resolution. The approach involves the utilization of tandem MS in conjunction with targeted RNA enrichment and enzymatic digestion, eliminating the need for PCR amplification. By employing this strategy, we can accurately identify m6A and m6Am sites in targeted RNA fragments with high confidence. To evaluate the effectiveness of our method, we applied it to detect m6A and m6Am sites in cell and tissue samples. Furthermore, we verified the accuracy of our approach by performing CRISPR/Cas9-mediated knockout of the corresponding methyltransferases. Overall, our MS-based method offers a reliable and precise means for the simultaneous detection of m6A and m6Am modifications in targeted RNA fragments, providing valuable insights into the functional characterization of these modifications in various biological contexts.

Fragmentation Pattern-Based Screening Strategy Combining Diagnostic Ion and Neutral Loss Uncovered Novel para-Phenylenediamine Quinone Contaminants in the Environment.

Identifying transformed emerging contaminants in complex environmental compartments is a challenging but meaningful task. Substituted para-phenylenediamine quinones (PPD-quinones) are emerging contaminants originating from rubber antioxidants and have been proven to be toxic to the aquatic species, especially salmonids. The emergence of multiple PPD-quinones in various environmental matrices and evidence of their specific hazards underscore the need to understand their environmental occurrences. Here, we introduce a fragmentation pattern-based nontargeted screening strategy combining full MS/All ion fragmentation/neutral loss-ddMS2 scans to identify potential unknown PPD-quinones in different environmental matrices. Using diagnostic fragments of m/z 170.0600, 139.0502, and characteristic neutral losses of 199.0633, 138.0429 Da, six known and three novel PPD-quinones were recognized in air particulates, surface soil, and tire tissue. Their specific structures were confirmed, and their environmental concentration and composition profiles were clarified with self-synthesized standards. N-(1-methylheptyl)-N'-phenyl-1,4-benzenediamine quinone (8PPD-Q) and N,N'-di(1,3-dimethylbutyl)-p-phenylenediamine quinone (66PD-Q) were identified and quantified for the first time, with their median concentrations found to be 0.02-0.21 µg·g-1 in tire tissue, 0.40-2.76 pg·m-3 in air particles, and 0.23-1.02 ng·g-1 in surface soil. This work provides new evidence for the presence of unknown PPD-quinones in the environment, showcasing a potential strategy for screening emerging transformed contaminants in the environment.

Forefronts and hotspots evolution of the nanomaterial application in anti-tumor immunotherapy: a scientometric analysis.

BACKGROUND: Tumor immunotherapy can not only eliminate the primary lesion, but also produce long-term immune memory, effectively inhibiting tumor metastasis and recurrence. However, immunotherapy also showed plenty of limitations in clinical practice. In recent years, the combination of nanomaterials and immunotherapy has brought new light for completely eliminating tumors with its fabulous anti-tumor effects and negligible side effects. METHODS: The Core Collection of Web of Science (WOSCC) was used to retrieve and obtain relevant literatures on antitumor nano-immunotherapy since the establishment of the WOSCC. Bibliometrix, VOSviewer, CiteSpace, GraphPad Prism, and Excel were adopted to perform statistical analysis and visualization. The annual output, active institutions, core journals, main authors, keywords, major countries, key documents, and impact factor of the included journals were evaluated. RESULTS: A total of 443 related studies were enrolled from 2004 to 2022, and the annual growth rate of articles reached an astonishing 16.85%. The leading countries in terms of number of publications were China and the United States. Journal of Controlled Release, Biomaterials, Acta Biomaterialia, Theranostics, Advanced Materials, and ACS Nano were core journals publishing high-quality literature on the latest advances in the field. Articles focused on dendritic cells and drug delivery accounted for a large percentage in this field. Key words such as regulatory T cells, tumor microenvironment, immune checkpoint blockade, drug delivery, photodynamic therapy, photothermal therapy, tumor-associated macrophages were among the hottest themes with high maturity. Dendritic cells, vaccine, and T cells tend to become the popular and emerging research topics in the future. CONCLUSIONS: The combined treatment of nanomaterials and antitumor immunotherapy, namely antitumor nano-immunotherapy has been paid increasing attention. Antitumor nano-immunotherapy is undergoing a transition from simple to complex, from phenotype to mechanism.

PM2.5-induced DNA oxidative stress in A549 cells and regulating mechanisms by GST DNA methylation and Keap1/Nrf2 pathway.

Fine particulate matter (PM2.5) increases the risks of lung cancer. Epigenetics provides a new toxicology mechanism for the adverse health effects of PM2.5. However, the regulating mechanisms of PM2.5 exposure on candidate gene DNA methylation changes in the development of lung cancer remain unclear. Abnormal expression of the glutathione S transferase (GST) gene is associated with cancer. However, the relationship between PM2.5 and DNA methylation-mediated GST gene expression is not well understood. In this study, we performed GST DNA methylation analysis and GST-related gene expression in human A549 cells exposed to PM2.5 (0, 50, 100 µg/mL, from Taiyuan, China) for 24 h (n = 4). We found that PM2.5 may cause DNA oxidative damage to cells and the elevation of GSTP1 promotes cell resistance to reactive oxygen species (ROS). The Kelch-1ike ECH-associated protein l (Keap1)/nuclear factor NF-E2-related factor 2 (Nrf2) pathway activates the GSTP1. The decrease in the DNA methylation level of the GSTP1 gene enhances GSTP1 expression. GST DNA methylation is associated with reduced levels of 5-methylcytosine (5mC), DNA methyltransferase 1 (DNMT1), and histone deacetylases 3 (HDAC3). The GSTM1 was not sensitive to PM2.5 stimulation. Our findings suggest that PM2.5 activates GSTP1 to defend PM2.5-induced ROS and 8-hydroxy-deoxyguanosine (8-OHdG) formation through the Keap1/Nrf2 signaling pathway and GSTP1 DNA methylation.

Occurrence and Fate of Substituted p-Phenylenediamine-Derived Quinones in Hong Kong Wastewater Treatment Plants.

para-Phenylenediamine quinones (PPD-Qs) are a newly discovered class of transformation products derived from para-phenylenediamine (PPD) antioxidants. These compounds are prevalent in runoff, roadside soil, and particulate matter. One compound among these, N-1,3-dimethylbutyl-n'-phenyl-p-phenylenediamine quinone (6PPD-Q), was found to induce acute mortality of coho salmon, rainbow trout, and brook trout, with the median lethal concentrations even lower than its appearance in the surface and receiving water system. However, there was limited knowledge about the occurrence and fate of these emerging environmental contaminants in wastewater treatment plants (WWTPs), which is crucial for effective pollutant removal via municipal wastewater networks. In the current study, we performed a comprehensive investigation of a suite of PPD-Qs along with their parent compounds across the influent, effluent, and biosolids during each processing unit in four typical WWTPs in Hong Kong. The total concentrations of PPDs and PPD-Qs in the influent were determined to be 2.7-90 and 14-830 ng/L. In the effluent, their concentrations decreased to 0.59-40 and 2.8-140 ng/L, respectively. The median removal efficiency for PPD-Qs varied between 53.0 and 91.0% across the WWTPs, indicating that a considerable proportion of these contaminants may not be fully eliminated through the current processing technology. Mass flow analyses revealed that relatively higher levels of PPD-Qs were retained in the sewage sludge (20.0%) rather than in the wastewater (16.9%). In comparison to PPDs, PPD-Qs with higher half-lives exhibited higher release levels via effluent wastewater, which raises particular concerns about their environmental consequences to aquatic ecosystems.

Validation of quercetin in the treatment of colon cancer with diabetes via network pharmacology, molecular dynamics simulations, and in vitro experiments.

This study built a prognostic model for CRC-diabetes and analyzed whether quercetin could be used for CRC-diabetes treatment through a network of pharmacology, molecular dynamics simulation, bioinformatics, and in vitro experiments. First, multivariate Cox proportional hazards regression was used to construct the prognosis modelof CRC-diabetes. Then, the intersection of quercetin target genes with CRC-diabetes genes was used to find the potential target for quercetin in the treatment of CRC-diabetes. Molecular docking and molecular dynamics simulations were used to screen the potential targets for quercetin in the treatment of CRC-diabetes. Finally, we verified the target and pathway of quercetin in the treatment of CRC-diabetes through in vitro experiments. Through molecular docking, seven proteins (HMOX1, ACE, MYC, MMP9, PLAU, MMP3, and MMP1) were selected as potential targets of quercetin. We conducted molecular dynamics simulations of quercetin and the above proteins, respectively, and found that the binding structure of quercetin with MMP9 and PLAU was relatively stable. Finally, according to the results of Western blot results, it was confirmed that quercetin could interact with MMP9. The experimental results show that quercetin may affect the JNK pathway, glycolysis, and epithelial-mesenchymal transition (EMT) to treat CRC-diabetes. Based on the TCGA, TTD, DrugBank, and other databases, a prediction model that can effectively predict the prognosis of colon cancer patients with diabetes was constructed. According to experiment results, quercetin can regulate the expression of MMP9. By acting on the JNK pathway, glycolysis, and EMT, it can treat colon cancer patients with diabetes.

Adverse effects of triclosan on kidney in mice: Implication of lipid metabolism disorders.

Triclosan (TCS) is a ubiquitous antimicrobial used in daily consumer products. Previous reports have shown that TCS could induce hepatotoxicity, endocrine disruption, disturbance on immune function and impaired thyroid function. Kidney is critical in the elimination of toxins, while the effects of TCS on kidney have not yet been well-characterized. The aim of the present study was to investigate the effects of TCS exposure on kidney function and the possible underlying mechanisms in mice. Male C57BL/6 mice were orally exposed to TCS with the doses of 10 and 100 mg/(kg•day) for 13 weeks. TCS was dissolved in dimethyl sulfoxide (DMSO) and diluted by corn oil for exposure. Corn oil containing DMSO was used as vehicle control. Serum and kidney tissues were collected for study. Biomarkers associated with kidney function, oxidative stress, inflammation and fibrosis were assessed. Our results showed that TCS could cause renal injury as was revealed by increased levels of renal function markers including serum creatinine, urea nitrogen and uric acid, as well as increased oxidative stress, pro-inflammatory cytokines and fibrotic markers in a dose dependent manner, which were more significantly in 100 mg/(kg•day) group. Mass spectrometry-based analysis of metabolites related with lipid metabolism demonstrated the occurrence of lipid accumulation and defective fatty acid oxidation in 100 mg/(kg•day) TCS-exposed mouse kidney. These processes might lead to lipotoxicity and energy depletion, thus resulting in kidney fibrosis and functional decline. Taken together, the present study demonstrated that TCS could induce lipid accumulation and fatty acid metabolism disturbance in mouse kidney, which might contribute to renal function impairment. The present study further widens our insights into the adverse effects of TCS.

3-Acetylpyridine On-Tissue Paternò-Büchi Derivatization Enabling High Coverage Lipid C═C Location-Resolved MS Imaging in Biological Tissues.

Unsaturated lipids containing single or more carbon-carbon double bonds (C═C) within tissues are closely associated with various types of diseases. Mass spectrometry imaging (MSI) has been used to study the spatial distribution of lipid C═C location isomers in tissue sections. However, comprehensive characterization of lipid C═C location isomers using MSI remains challenging. Herein, we established an on-tissue charge-switching Paternò-Büchi (PB) derivatization method using 3-acetylpyridine (3-AP) as a reaction reagent, which can be used to detect and assign C═C location of glycerophospholipids (GPLs) as well as neutral lipids, such as fatty acids (FAs), under the same experimental workflow using matrix-assisted laser desorption/ionization (MALDI)-MSI. High coverage of mono- and poly-unsaturated C═C location isomers among various lipid classes including FA, phosphatidylcholine (PC), and sulfatide (SHexCer) in distinct regions of the mouse brain and kidney was visualized using MALDI-MS/MS imaging. This method has also been applied to map the spatial distribution of lipid C═C location isomers in the Alzheimer's disease (AD) mice model for the first time, which provides a new tool to study the relationships between the distribution of lipid structural diversity and neurodegenerative diseases.

An AGS-associated mutation in ADAR1 catalytic domain results in early-onset and MDA5-dependent encephalopathy with IFN pathway activation in the brain.

BACKGROUND: Aicardi-Goutières syndrome (AGS) is a severe neurodegenerative disease with clinical features of early-onset encephalopathy and progressive loss of intellectual abilities and motor control. Gene mutations in seven protein-coding genes have been found to be associated with AGS. However, the causative role of these mutations in the early-onset neuropathogenesis has not been demonstrated in animal models, and the mechanism of neurodegeneration of AGS remains ambiguous. METHODS: Via CRISPR/Cas-9 technology, we established a mutant mouse model in which a genetic mutation found in AGS patients at the ADAR1 coding gene (Adar) loci was introduced into the mouse genome. A mouse model carrying double gene mutations encoding ADAR1 and MDA-5 was prepared using a breeding strategy. Phenotype, gene expression, RNA sequencing, innate immune pathway activation, and pathologic studies including RNA in situ hybridization (ISH) and immunohistochemistry were used for characterization of the mouse models to determine potential disease mechanisms. RESULTS: We established a mouse model bearing a mutation in the catalytic domain of ADAR1, the D1113H mutation found in AGS patients. With this mouse model, we demonstrated a causative role of this mutation for the early-onset brain injuries in AGS and determined the signaling pathway underlying the neuropathogenesis. First, this mutation altered the RNA editing profile in neural transcripts and led to robust IFN-stimulated gene (ISG) expression in the brain. By ISH, the brains of mutant mice showed an unusual, multifocal increased expression of ISGs that was cell-type dependent. Early-onset astrocytosis and microgliosis and later stage calcification in the deep white matter areas were observed in the mutant mice. Brain ISG activation and neuroglial reaction were completely prevented in the Adar D1113H mutant mice by blocking RNA sensing through deletion of the cytosolic RNA receptor MDA-5. CONCLUSIONS: The Adar D1113H mutation in the ADAR1 catalytic domain results in early-onset and MDA5-dependent encephalopathy with IFN pathway activation in the mouse brain.

New Evidence of Rubber-Derived Quinones in Water, Air, and Soil.

p-Phenylenediamines (PPDs) have been extensively used in the rubber industry and found to be pervasive in various environmental compartments for decades, while their transformation products and associated ecological and human health risks remain largely unknown. Herein, we developed and implemented a mass spectrometry-based platform combined with self-synthesized standards for the investigation of rubber-derived quinones formed from PPD antioxidants. Our results demonstrated that five quinones are ubiquitously present in urban runoff, roadside soils, and air particles. All of the identified sources are closely related to mankind's activities. Among the identified quinones, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone has been recently found to be highly toxic, causing acute mortality of coho salmon in the Pacific Northwest. Ultrahigh-performance liquid chromatography coupled with triple quadrupole mass spectrometry was then applied for quantification of the five quinones and their corresponding PPD antioxidants. The results revealed interesting distinct distribution and concentration patterns of PPD-derived quinones in different environmental matrices. Daily intake rates of these quinones in a compact city of Hong Kong were estimated to be varied from 1.08 ng/(kg·day) for adults to 7.30 ng/(kg·day) for children, which were higher than the exposure levels of their parent compounds. Considering the prevalence of the use of rubber products, the outcome of this study strongly suggests for additional toxicological studies to investigate potential ecological and human health risks of the newly discovered quinones.

Beyond Substituted p-Phenylenediamine Antioxidants: Prevalence of Their Quinone Derivatives in PM2.5.

Substituted para-phenylenediamine (PPD) antioxidants have been extensively used to retard oxidative degradation of tire rubber and were found to pervade multiple environmental compartments. However, there is a paucity of research on the environmental occurrences of their transformation products. In this study, we revealed the co-occurrence of six PPD-derived quinones (PPD-Qs) along with eight PPDs in fine particulate matter (PM2.5) from two Chinese megacities, in which N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine quinone (77PD-Q) was identified and quantified for the first time. Prevalent occurrences of these emerging PPD-Qs were found in Taiyuan (5.59-8480 pg/m3) and Guangzhou (3.61-4490 pg/m3). Significantly higher levels of PPDs/PPD-Qs were observed at a roadside site, implying the possible contribution of vehicle emissions. Correlation analysis implied potential consistencies in the fate of these PPD-Qs and suggested that most of them were originated from the transformation of their parent PPDs. For different subpopulation groups under different exposure scenarios, the estimated daily intakes of PPD-Qs (0.16-1.25 ng kgbw-1 day-1) were comparable to those of their parent PPDs (0.19-1.41 ng kgbw-1 day-1), suggesting an important but overlooked exposure caused by novel PPD-Qs. Given the prolonged exposure of these antioxidants and their quinone derivatives to traffic-relevant occupations, further investigations on their toxicological and epidemiological effects are necessary.

Influence of COVID-19 lockdown on the variation of organic aerosols: Insight into its molecular composition and oxidative potential.

To prevent the transmission of the novel coronavirus disease 2019 (COVID-19), China adopted nationwide lockdown measures on January 25, 2020, leading to an evident diminution in the observed air pollutants. To investigate the influence of the lockdown on atmospheric chemistry, the specific molecular composition, oxidative potential of organic aerosols (OAs) in PM2.5 were studied using a high-resolution orbitrap mass spectrometry at a typical coal-combustion city, Linfen, in the North China Plain (NCP). The major air pollutants including PM2.5, PM10, SO2, NO2, and CO were observed to be diminished by 28.6-45.4%, while O3 was augmented by 52.5% during the lockdown compared to those before the lockdown. A significant decrease of oxygen-containing (CHO) compounds (24.7%) associated with anthropogenic acids was observed during the lockdown, implying a reduction in fossil fuel combustion. The coal-burning related sulfur-containing organosulfates (CHOS-) and nitrooxy-sulfates (CHONS-) have also shown attenuated in both their relative abundances and anthropogenic/biogenic ratios. Amine/amide-like CHON + components have decreased by 27.6%, while nitro/nitrooxy-containing CHON- compounds have only decreased by 7.1%. Multi-source nitrogen-containing (CHN) compounds have shown a moderate elimination of 24.0%, while the identified high-condensed azaarenes have fallen from 17.7% to 14.7%, implying a potential reduction in the health risk of OAs during quarantine. The measurement of OAs' oxidative potential through dithiothreitol (DTT) assay has confirmed that as it had dropped from 0.88 nmol min-1 m-3 to 0.80 nmol min-1 m-3. High correlations were observed between the abundance of OA subgroups with the concentration of PM2.5 after the execution of the lockdown, suggesting a potential elevation in the contribution of organic components to the total PM2.5 level. Our study provides insightful compositional and health-related information in the variation of OAs during the lockdown period and attests to the validity of joint-control strategy in controlling the level and health risks of numerous atmospheric pollutants.

[Hydrogen Sulfide Ameliorates Myocardial Injury Caused by Sepsis Through Suppressing ROS-Mediated Endoplasmic Reticulum Stress].

Objective: To investigate the effect of hydrogen sulfide (H 2S) on reactive oxygen species (ROS)-mediated endoplasmic reticulum stress in myocardial injury caused by sepsis. Methods: A sepsis model was induced in Sprague-Dawley (SD) rats by cecal ligation and puncture (CLP). The rats were randomly divided into sham operation (sham) group, sepsis (CLP) group, and sepsis+sodium hydrosulfide (NaHS) (CLP+NaHS) group. The left ventricular function of the rats was observed with echocardiography and their plasma H 2S levels were measured. Lactate dehydrogenase (LDH), malondialdehyde (MDA), glutathione (GSH) levels were measured and HE staining was done to evaluate the level of myocardial oxidative stress in rats. HE staining was done to observe the morphological changes of rat myocardium, and transmission electron microscope was used to observe the ultrastructure of myocardial mitochondria. Western blot was done to examine changes in the expression of two endogenous hydrogen sulfide synthases, cystathionine γ-lyase (CSE) and 3-mercaptopyruvate sulfur transferase (3-MST), and changes in the expression of endoplasmic reticulum stress (ERS) marker proteins, including phosphorylated (p) protein kinase R-like endoplasmic reticulum kinase (p-PERK), p-eukaryotic translation initiation factor 2α (p-eIF2α), p-inositol requires enzyme 1α (IRE1α), recombinant activating transcription factor 4 (ATF4), and C/EBP homologous protein (CHOP). TUNEL staining was performed to observe the changes of cardiomyocyte apoptosis in rats. Results: Left ventricular ejection fraction (LVEF), left ventricular shortening fraction (LVFS) and plasma H 2S decreased in septic rats ( P<0.05). Plasma H 2S exhibited linear correlation with LVEF and LVFS ( r 2=0.62 and r 2=0.64, all P<0.05). The ROS levels were significantly elevated in rats of the CLP group. In addition, these rats showed increased level of LDH ( P<0.05), increased expression of MDA ( P<0.05), and decreased expression of GSH ( P<0.05). Inflammatory cell infiltration and cardiomyocyte edema were observed in HE staining. Transmission electron microscopic observation revealed significant mitochondrial damage, observable mitochondrial edema, and cristae structure dissolution. The Western blot results showed that the expression levels of CSE and 3-MST decreased ( P<0.05), while the ERS marker proteins, including p-PERK, p-eIF2, IRE1α, ATF4, and CHOP, were expressed at increased levels ( P<0.05). TUNEL staining showed significant increase of apoptosis in cardiomyocytes ( P<0.05). After NaHS treatment, LVEF and LVFS increased ( P<0.05) and plasma H 2S increased in septic rats ( P<0.05). Myocardial oxidative stress levels decreased. HE staining and transmission electron microscopy showed improved myocardial morphology. Mitochondrial damage was reduced and CSE and 3-MST levels were significantly increased ( P<0.05). The expression of p-PERK, p-eIF2α, p-IRE1α, and CHOP proteins decreased ( P<0.05). A decrease in cardiomyocyte apoptosis levels was observed by TUNEL staining ( P<0.05). Conclusion: H 2S reduces septic cardiomyocyte apoptosis by inhibiting ROS-mediated ERS, thereby improving myocardial dysfunction in sepsis.

Attenuating vascular stenosis-induced astrogliosis preserves white matter integrity and cognitive function.

BACKGROUND: Chronic cerebral hypoperfusion (CCH) causes white matter damage and cognitive impairment, in which astrogliosis is the major pathology. However, underlying cellular mechanisms are not well defined. Activation of Na+/H+ exchanger-1 (NHE1) in reactive astrocytes causes astrocytic hypertrophy and swelling. In this study, we examined the role of NHE1 protein in astrogliosis, white matter demyelination, and cognitive function in a murine CCH model with bilateral carotid artery stenosis (BCAS). METHODS: Sham, BCAS, or BCAS mice receiving vehicle or a selective NHE1 inhibitor HOE642 were monitored for changes of the regional cerebral blood flow and behavioral performance for 28 days. Ex vivo MRI-DTI was subsequently conducted to detect brain injury and demyelination. Astrogliosis and demyelination were further examined by immunofluorescence staining. Astrocytic transcriptional profiles were analyzed with bulk RNA-sequencing and RT-qPCR. RESULTS: Chronic cerebral blood flow reduction and spatial working memory deficits were detected in the BCAS mice, along with significantly reduced mean fractional anisotropy (FA) values in the corpus callosum, external capsule, and hippocampus in MRI DTI analysis. Compared with the sham control mice, the BCAS mice displayed demyelination and axonal damage and increased GFAP+ astrocytes and Iba1+ microglia. Pharmacological inhibition of NHE1 protein with its inhibitor HOE642 prevented the BCAS-induced gliosis, damage of white matter tracts and hippocampus, and significantly improved cognitive performance. Transcriptome and immunostaining analysis further revealed that NHE1 inhibition specifically attenuated pro-inflammatory pathways and NADPH oxidase activation. CONCLUSION: Our study demonstrates that NHE1 protein is involved in astrogliosis with pro-inflammatory transformation induced by CCH, and its blockade has potentials for reducing astrogliosis, demyelination, and cognitive impairment.

Integrated Proteomics and Metabolomics Assessment Indicated Metabolic Alterations in Hypothalamus of Mice Exposed to Triclosan.

Triclosan (TCS) is a ubiquitous antimicrobial used in many daily consumer products. It has been reported to induce endocrine disrupting effects at low doses in mammals, disturbing sex hormone function and thyroid function. The hypothalamus plays a crucial role in the maintenance of neuroendocrine function and energy homeostasis. We speculated that the adverse effects of TCS might be related to the disturbance of metabolic processes in hypothalamus. The present study aimed at investigating the effects of TCS exposure on the protein and metabolite profiles in hypothalamus of mice. Male C57BL/6 mice were orally exposed to TCS at the dosage of 10 mg/kg/d for 13 weeks. The hypothalamus was isolated and processed for mass spectrometry (MS)-based proteomics and metabolomics analyses. The results showed that a 10.6% decrease (P = 0.066) in body weight gain was observed in the TCS exposure group compared with vehicle control group. Differential analysis defined 52 proteins and 57 metabolites that delineated TCS exposed mice from vehicle controls. Among the differential features, multiple proteins and metabolites were found to play vital roles in neuronal signaling and function. Bioinformatics analysis revealed that these differentially expressed proteins and metabolites were involved in four major biological processes, including glucose metabolism, purine metabolism, neurotransmitter release, and neural plasticity, suggesting the disturbance of homeostasis in energy metabolism, mitochondria function, neurotransmitter system, and neuronal function. Our results may provide insights into the neurotoxicity of TCS and extend our understanding of the biological effects induced by TCS exposure.

Fenton/Fenton-like metal-based nanomaterials combine with oxidase for synergistic tumor therapy.

Chemodynamic therapy (CDT) catalyzed by transition metal and starvation therapy catalyzed by intracellular metabolite oxidases are both classic tumor treatments based on nanocatalysts. CDT monotherapy has limitations including low catalytic efficiency of metal ions and insufficient endogenous hydrogen peroxide (H2O2). Also, single starvation therapy shows limited ability on resisting tumors. The "metal-oxidase" cascade catalytic system is to introduce intracellular metabolite oxidases into the metal-based nanoplatform, which perfectly solves the shortcomings of the above-mentioned monotherapiesIn this system, oxidases can not only consume tumor nutrients to produce a "starvation effect", but also provide CDT with sufficient H2O2 and a suitable acidic environment, which further promote synergy between CDT and starvation therapy, leading to enhanced antitumor effects. More importantly, the "metal-oxidase" system can be combined with other antitumor therapies (such as photothermal therapy, hypoxia-activated drug therapy, chemotherapy, and immunotherapy) to maximize their antitumor effects. In addition, both metal-based nanoparticles and oxidases can activate tumor immunity through multiple pathways, so the combination of the "metal-oxidase" system with immunotherapy has a powerful synergistic effect. This article firstly introduced the metals which induce CDT and the oxidases which induce starvation therapy and then described the "metal-oxidase" cascade catalytic system in detail. Moreover, we highlight the application of the "metal-oxidase" system in combination with numerous antitumor therapies, especially in combination with immunotherapy, expecting to provide new ideas for tumor treatment.

A 4-gene-based hypoxia signature is associated with tumor immune microenvironment and predicts the prognosis of pancreatic cancer patients.

BACKGROUND: Pancreatic cancer (PAC) is one of the most devastating cancer types with an extremely poor prognosis, characterized by a hypoxic microenvironment and resistance to most therapeutic drugs. Hypoxia has been found to be one of the factors contributing to chemoresistance in PAC, but also a major driver of the formation of the tumor immunosuppressive microenvironment. However, the method to identify the degree of hypoxia in the tumor microenvironment (TME) is incompletely understood. METHODS: The mRNA expression profiles and corresponding clinicopathological information of PAC patients were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database, respectively. To further explore the effect of hypoxia on the prognosis of patients with PAC as well as the tumor immune microenvironment, we established a hypoxia risk model and divided it into high- and low-risk groups in line with the hypoxia risk score. RESULTS: We established a hypoxia risk model according to four hypoxia-related genes, which could be used to demonstrate the immune microenvironment in PAC and predict prognosis. Moreover, the hypoxia risk score can act as an independent prognostic factor in PAC, and a higher hypoxia risk score was correlated with poorer prognosis in patients as well as the immunosuppressive microenvironment of the tumor. CONCLUSIONS: In summary, we established and validated a hypoxia risk model that can be considered as an independent prognostic indicator and reflected the immune microenvironment of PAC, suggesting the feasibility of hypoxia-targeted therapy for PAC patients.

Application of a real-ambient fine particulate matter exposure system on different animal models.

Simulation of fine particulate matter (PM2.5) exposure is essential for evaluating adverse health effects. In this work, an ambient exposure system that mimicked real atmospheric conditions was installed in Taiyuan, China to study impacts of chronic PM2.5 exposure on adult and aged mice as well as Sirtuin3 knockout (Sirt3 KO) mice and wild-type (WT) mice. The real-ambient exposure system eliminated the possible artificial effects caused from exposure experiments and maintained the physiochemical characteristics of PM2.5. The case studies indicated that aged mice exhibited apparent heart dysfunction involving increased heart rate and decreased blood pressure after 17-week of real-ambient PM2.5 exposure. Meanwhile, 15-week of real-ambient PM2.5 exposure decreased the heart rate and amounts of associated catecholamines to induce heart failure in Sirt3 KO mice. Additionally, the increased pro-inflammatory cytokines and decreased platelet related indices suggested that inflammation occurred. The changes of biomarkers detected by targeted metabolomics confirmed metabolic disorder in WT and Sirt3 KO mice after exposed to real-ambient PM2.5. These results indicated that the real-ambient PM2.5 exposure system could evaluate the risks of certain diseases associated with air pollution and have great potential for supporting the investigations of PM2.5 effects on other types of rodent models.