ABSTRACT
Nattokinase (NK) is an enzyme that has been recognized as a new potential thrombolytic drug due to its strong thrombolytic activity. However, it is difficult to maintain the enzyme activity of NK during high temperature environment of industrial production. In this study, we constructed six NK mutants with potential for higher thermostability using a rational protein engineering strategy integrating free energy-based methods and molecular dynamics (MD) simulation. Then, wild-type NK and NK mutants and were expressed in Escherichia coli (E. coli), and their thermostability and thrombolytic activity were tested. The results showed that, compared with wild-type NK, the mutants Y256P, Q206L and E156F all had improved thermostability. The optimal mutant Y256P showed a higher melting temperature (Tm) of 77.4 °C, an increase of 4 °C in maximum heat-resistant temperature and an increase of 51.8% in activity at 37 °C compared with wild-type NK. Moreover, we also explored the mechanism of the increased thermostability of these mutants by analysing the MD trajectories under different simulation temperatures.
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Surface-enhanced Raman spectroscopy (SERS) is a powerful technique for discrimination of bimolecules in complex systems. However, its practical applications face challenges such as complicated manufacturing procedures and limited scalability of SERS substrates, as well as poor reproducibility during detection which compromises the reliability of SERS-based analysis. In this study, we developed a convenient method for simultaneous fabrication of massive SERS substrates with an internal standard to eliminate the substrate-to-substrate differences. We first synthesized Au@CN@Au nanoparticles (NPs) which contain embedded internal standard molecules with a single characteristic peak in the Raman-silent region, and then deposited the NPs on 6 mm glass wafers in a 96-well plate simply by centrifugation for 3 min. The one-time obtained 96 SERS substrates have excellent intrasubstrate uniformity and intersubstrate repeatability for SERS detection by using the internal standard (relative standard deviation = 10.47%), and were able to detect both charged and neutral molecules (crystal violet and triphenylphosphine) at a concentration of 10-9 M. Importantly, cells can be directly cultured on glass wafers in the 96-well plate, enabling real time monitoring of the secretes and metabolism change in response to external stimulation. We found that the release of nucleic acids, amino acids and lipids by MDA-MB-231 cells significantly increased under hypoxic conditions. Overall, our approach enables fast and large-scale production of Au@CN@Au NPs-coated glass wafers as SERS substrates, which are homogeneous and highly sensitive for monitoring trace changes of biomolecules.
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S100 proteins comprise a family of structurally related proteins that are calcium-sensitive. S100 proteins have been found to play various roles in regulation of cell apoptosis, cell proliferation and differentiation, cell migration and invasion, energy metabolism, calcium homeostasis, protein phosphorylation, anti-microbial activity and inflammation in a variety of cell types. While the specific function of many S100 proteins remains unknown, some of the S100 proteins serve as disease biomarkers as well as possible therapeutic targets in skin diseases. Interface dermatitis (ID) is a histopathological term that covers many different skin conditions including cutaneous lupus erythematosus, lichen planus, and dermatomyositis. These pathologies share similar histological features, which include basal cell vacuolization and lymphocytic infiltration at the dermal-epidermal junction. In this review, we summarize how the S100 protein family contributes to both homeostatic and inflammatory processes in the skin. We also highlight the role of S100 proteins in neuronal signalling, describing how this might contribute to neuroimmune interactions in ID and other skin pathologies. Last, we discuss what is known about the S100 family proteins as both biomarkers and potential treatment targets in specific pathologies.
Subject(s)
Homeostasis , S100 Proteins , Skin , Humans , S100 Proteins/metabolism , Skin/metabolism , Skin/pathology , Dermatitis/metabolism , Skin Diseases/metabolism , Biomarkers/metabolism , AnimalsABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Linggui-Zhugan (LGZG) comprises four herbs and is a classic formula in traditional Chinese medicine. There is strong clinical evidence of its pleiotropic effects in the prevention of diabetes and its related complications. Although several classes of drugs are currently available for clinical management of diabetic kidney disease (DKD), tight glycemic and/or hypertension control may not prevent disease progression. This study evaluated the therapeutic effect of the ethnopharmacological agent LGZG on DKD. AIM OF THE STUDY: This study aimed to investigate the effects of LGZG formula with standard quality control on experimental DKD and its related metabolic disorders in animal model. Meanwhile, the present study aimed to investigate regulatory effects of LGZG on renal proteinase 3 (PR3) to reveal mechanisms underlying renoprotective benefits of LGZG. MATERIALS AND METHODS: LGZG decoction was fingerprinted by high-performance liquid chromatography for quality control. An experimental model of DKD was induced in C57 BL/6J mice by a combination of high-fat diet feeding, uninephrectomy, and intraperitoneal injection of streptozocin. The LGZG decoction was administrated by daily oral gavage. RESULTS: Treatment with LGZG formula significantly attenuated DKD-like traits (including severe albuminuria, mesangial matrix expansion, and podocyte loss) and metabolic dysfunction (disordered body composition and dyslipidemia) in mice. RNA sequencing data revealed a close association of LGZG treatment with marked modulation of signaling pathways related to podocyte injury and cell apoptosis. Mechanistically, LGZG suppressed the DKD-triggered increase in renal PR3 and podocyte apoptosis. In-vitro incubation of mouse immortalized podocytes with LGZG-medicated serum attenuated PR3-mediated apoptosis. CONCLUSION: Our data demonstrated that the LGZG formula protected against DKD in mice and was closely associated with its inhibitory effects on PR3-mediated podocyte apoptosis.
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BACKGROUND: Gastric cancer (GC) is a prevalent malignant tumor, and the RNA-binding protein polypyrimidine tract-binding protein 1 (PTBP1) has been identified as a crucial factor in various tumor types. Moreover, abnormal autophagy levels have been shown to significantly impact tumorigenesis and progression. Despite this, the precise regulatory mechanism of PTBP1 in autophagy regulation in GC remains poorly understood. METHODS: To assess the expression of PTBP1 in GC, we employed a comprehensive approach utilizing western blot, real-time quantitative polymerase chain reaction (RT-qPCR), and bioinformatics analysis. To further identify the downstream target genes that bind to PTBP1 in GC cells, we utilized RNA immunoprecipitation coupled with sequencing (si-PTBP1 RNA-seq). To evaluate the impact of PTBP1 on gastric carcinogenesis, we conducted CCK-8 assays, colony formation assays, and GC xenograft mouse model assays. Additionally, we utilized a transmission electron microscope, immunofluorescence, flow cytometry, western blot, RT-qPCR, and GC xenograft mouse model experiments to elucidate the specific mechanism underlying PTBP1's regulation of autophagy in GC. RESULTS: Our findings indicated that PTBP1 was significantly overexpressed in GC tissues compared with adjacent normal tissues. Silencing PTBP1 resulted in abnormal accumulation of autophagosomes, thereby inhibiting GC cell viability both in vitro and in vivo. Mechanistically, interference with PTBP1 promoted the stability of thioredoxin-interacting protein (TXNIP) mRNA, leading to increased TXNIP-mediated oxidative stress. Consequently, this impaired lysosomal function, ultimately resulting in blockage of autophagic flux. Furthermore, our results suggested that interference with PTBP1 enhanced the antitumor effects of chloroquine, both in vitro and in vivo. CONCLUSION: PTBP1 knockdown impairs GC progression by directly binding to TXNIP mRNA and promoting its expression. Based on these results, PTBP1 emerges as a promising therapeutic target for GC.
Subject(s)
Autophagy , Carrier Proteins , Heterogeneous-Nuclear Ribonucleoproteins , Oxidative Stress , Polypyrimidine Tract-Binding Protein , Stomach Neoplasms , Polypyrimidine Tract-Binding Protein/metabolism , Polypyrimidine Tract-Binding Protein/genetics , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Autophagy/genetics , Humans , Heterogeneous-Nuclear Ribonucleoproteins/metabolism , Heterogeneous-Nuclear Ribonucleoproteins/genetics , Animals , Carrier Proteins/metabolism , Carrier Proteins/genetics , Oxidative Stress/genetics , Cell Line, Tumor , Mice , Disease Progression , Mice, Nude , Gene Expression Regulation, Neoplastic , Cell Proliferation/genetics , Gene Knockdown Techniques , Mice, Inbred BALB C , MaleABSTRACT
Alginate is a commercially important polysaccharide widely distributed in brown algae. Carbohydrate-binding modules (CBMs), a class of commonly used polysaccharide-binding proteins, have greatly facilitated the investigations of polysaccharides. Few alginate-binding CBMs have been hitherto reported and structurally characterized. Herein, an unknown domain from a potential PL6 family alginate lyase in the marine bacterium Vibrio breoganii was discovered and recombinantly expressed. The obtained protein, designated VbCBM106, displayed the favorable specificity to alginate. The unique sequence and well-defined function of VbCBM106 reveal a new CBM family (CBM106). Moreover, the structure of VbCBM106 was determined at a 1.5 Å resolution by the X-ray crystallography, which shows a typical ß-sandwich fold comprised of two antiparallel ß-sheets. Site-directed mutagenesis assays confirmed that positively charged polar residues are crucial for the ligand binding of VbCBM106. The discovery of VbCBM106 enriches the toolbox of alginate-binding proteins, and the elucidation of critical residues would guide the future practical applications of VbCBM106.
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Bedaquiline (BDQ), a first-in-class diarylquinoline anti-tuberculosis drug, and its analogue, TBAJ-587, prevent the growth and proliferation of Mycobacterium tuberculosis by inhibiting ATP synthase1,2. However, BDQ also inhibits human ATP synthase3. At present, how these compounds interact with either M. tuberculosis ATP synthase or human ATP synthase is unclear. Here we present cryogenic electron microscopy structures of M. tuberculosis ATP synthase with and without BDQ and TBAJ-587 bound, and human ATP synthase bound to BDQ. The two inhibitors interact with subunit a and the c-ring at the leading site, c-only sites and lagging site in M. tuberculosis ATP synthase, showing that BDQ and TBAJ-587 have similar modes of action. The quinolinyl and dimethylamino units of the compounds make extensive contacts with the protein. The structure of human ATP synthase in complex with BDQ reveals that the BDQ-binding site is similar to that observed for the leading site in M. tuberculosis ATP synthase, and that the quinolinyl unit also interacts extensively with the human enzyme. This study will improve researchers' understanding of the similarities and differences between human ATP synthase and M. tuberculosis ATP synthase in terms of the mode of BDQ binding, and will allow the rational design of novel diarylquinolines as anti-tuberculosis drugs.
Subject(s)
Antitubercular Agents , Diarylquinolines , Imidazoles , Mitochondrial Proton-Translocating ATPases , Mycobacterium tuberculosis , Piperidines , Pyridines , Humans , Antitubercular Agents/pharmacology , Antitubercular Agents/chemistry , Binding Sites , Cryoelectron Microscopy , Diarylquinolines/chemistry , Diarylquinolines/pharmacology , Imidazoles/chemistry , Imidazoles/pharmacology , Mitochondrial Proton-Translocating ATPases/antagonists & inhibitors , Mitochondrial Proton-Translocating ATPases/chemistry , Mitochondrial Proton-Translocating ATPases/metabolism , Mitochondrial Proton-Translocating ATPases/ultrastructure , Models, Molecular , Mycobacterium tuberculosis/enzymology , Mycobacterium tuberculosis/drug effects , Piperidines/chemistry , Piperidines/pharmacology , Protein Subunits/metabolism , Protein Subunits/chemistry , Protein Subunits/antagonists & inhibitors , Pyridines/chemistry , Pyridines/pharmacologyABSTRACT
The continuous expansion of modern cities not only leads to ecological degradation but also seriously threatens regional ecological security and sustainable development. The construction of ecological security patterns (ESPs) has emerged as a significant approach to alleviate or even solve the conflict between regional development and ecological protection. The Chengdu-Chongqing Economic Circle (CCEC) represents the core area of regional economic development strategy in western China, characterized by rapid economic growth from 2000 to 2020. This study integrates assessments of ecosystem services importance, eco-environmental sensitivity and landscape connectivity; uses circuit theory and hydrological analysis to establish a research framework for the spatiotemporal evolution of regional ESP; and develops an optimized ESP combined with the Major Function Oriented Zone. The results indicate that urban expansion significantly impacted the ESP of the CCEC between 2000 and 2020. The fragmentation and merging of ecological sources occurred simultaneously, the number of patches reduced by 28.13% from 64 to 46. The early ecological security network was compromised, leading to the disappearance or elongation of some ecological corridors. The number of ecological corridors decreased by 36.03% from 136 to 87; the total length was reduced by 29.92% from 7500.57 km to 5256.28 km. Urgent optimization of the ESP is needed, reducing the number of key ecological protection areas by 50% from 106 to 53 while increasing priority restoration areas by 13.51% from 37 to 42. The study also reveals the insufficiency of the current Major Function Oriented Zone in protecting linear corridors, necessitating focused attention on the protection and restoration of ecological sources and surrounding corridors in important development zones. Additionally, a spatial optimization strategy of "one shelter, two cores, and three regions" is proposed to enhance regional ecosystem stability and connectivity. The aim was to strike a balance between ecological protection and food security by recommending an ecological corridor width range of 30â¼100 m. These research findings offer scientific guidance for ecological space protection and restoration in the CCEC, contributing to the enhancement of both scientific and rational ecological planning in rapidly urbanizing areas.
Subject(s)
Conservation of Natural Resources , Ecology , Ecosystem , Urbanization , China , Economic DevelopmentABSTRACT
MicroRNAs (miRNAs) are implicated in the development of cancers and may serve as potential targets for therapy. However, the functions and underlying mechanisms of miRNAs in cancers are not well understood. This work aims to study the role of miR-373-3p in colon cancer cells. We find that the expression of miR-373-3p mimics promotes and the miR-373-3p inhibitor suppresses aerobic glycolysis and proliferation of colon cancer cells. Mechanistically, miR-373-3p inhibits the expression of MFN2, a gene that is known to suppress glycolysis, which leads to the activation of glycolysis and eventually the proliferation of cells. In a nude mouse tumor model, the expression of miR-373-3p in colon cancer cells promotes tumor growth by enhancing lactate formation, which is inhibited by the co-expression of MFN2 in the cells. Administration of the miR-373-3p antagomir blunts in vivo tumor growth by decreasing lactate production. In addition, in human colon cancers, the expression levels of miR-373-3p are increased, while those of MFN2 mRNA are decreased, and the increase of miR-373-3p is associated with the decrease of MFN2 mRNA. Our results reveal a previously unknown function and underlying mechanism of miR-373-3p in the regulation of glycolysis and proliferation in cancer cells and underscore the potential of targeting miR-373-3p for colon cancer treatment.
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Contrast-induced acute kidney injury (CI-AKI) is a prevalent cause of renal dysfunction among hospitalized patients, yet the precise pathogenesis and effective therapeutic strategies remain elusive. In this study, we investigated the role of tubular ferroptosis in both experimental CI-AKI models and in primary tubular epithelial cells (PTECs) treated with ioversol. Using whole exome sequencing, we identified metallothioneins (MTs) as being among the most significantly downregulated genes following ioversol exposure. Our findings reveal that overexpression of Mt1 mitigates, whereas suppression of Mt-1 exacerbates, ioversol-induced tubular ferroptosis. Interestingly, the level of MTF1 (metal regulatory transcription factor 1), a principal regulator of Mt1, was found to increase in response to ioversol treatment. We further elucidated that ioversol activates LATS1 (Large tumor suppressor homolog 1), a kinase that promotes the phosphorylation and nuclear translocation of MTF1, thereby inhibiting its transcriptional activity for Mt1. Both genetic and pharmacological inhibition of LATS1 reversed the ioversol-induced suppression of Mt-1. From a therapeutic perspective, the LATS1 inhibitor TDI-011536, in combination with zinc acetate, was administered to a rodent model of CI-AKI. Our data indicate that this combination synergistically upregulates Mt1 expression and provides protection against contrast media-induced tubular ferroptosis. In summary, our study demonstrates that the reduction of Mt-1 contributes to tubular ferroptosis associated with CI-AKI. We show that contrast media activate LATS1, which in turn suppresses the transcriptional activity of MTF1 for Mt1. Herein, the combination of zinc acetate and a LATS1 inhibitor emerges as a potential therapeutic approach for the treatment of CI-AKI.
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Influenza A virus (IAV) is the leading cause of highly contagious respiratory infections, which poses a serious threat to public health. The non-structural protein 1 (NS1) is encoded by segment 8 of IAV genome and is expressed in high levels in host cells upon IAV infection. It is the determinant of virulence and has multiple functions by targeting type Ι interferon (IFN-I) and type III interferon (IFN-III) production, disrupting cell apoptosis and autophagy in IAV-infected cells, and regulating the host fitness of influenza viruses. This review will summarize the current research on the NS1 including the structure and related biological functions of the NS1 as well as the interaction between the NS1 and host cells. It is hoped that this will provide some scientific basis for the prevention and control of the influenza virus.
Subject(s)
Influenza A virus , Influenza, Human , Viral Nonstructural Proteins , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism , Humans , Influenza A virus/genetics , Influenza A virus/pathogenicity , Influenza A virus/physiology , Influenza, Human/virology , Animals , Autophagy , Virulence , Host-Pathogen Interactions , Apoptosis , Interferons/metabolism , Interferons/immunology , Interferons/geneticsABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Zuogui Pill (ZGP) is a traditional herbal formula of Chinese Medicine with a long history of use in alleviating ovarian aging. AIM OF THE STUDY: To examine the impact of ZGP on oxidative stress and the stemness of oogonial stem cells (OSCs) in cyclophosphamide (CTX)-induced ovarian aging, as well as its molecular mechanisms involving the nuclear factor erythroid 2-related factor 2 (Nrf2, NFE2L2)/heme oxygenase-1 (HO-1, Hmox1) pathway. MATERIALS AND METHODS: Female Sprague-Dawley (SD) rats were randomly divided into seven groups: control, model (CTX), estradiol valerate (EV, 0.103 mg/kg), ZGP-L (low dose Zuogui Pill, 1.851 g/kg), ZGP-H (high dose Zuogui Pill, 3.702 g/kg), ML385 (30 mg/kg), and ML385+ZGP-L. After CTX modeling, the EV, ZGP-L, ZGP-H, and ML385+ZGP-L groups were treated by gavage for 8 weeks, while the ML385 and ML385+ZGP-L groups were administered the Nrf2 antagonist ML385 twice a week. OSCs were isolated after modeling and then treated with drug serum containing 10% ZGP or 10 µM ML385. The general conditions of the rats, including body weight, ovarian weight/body weight ratio, and estrous cycle, were observed. Ovarian ultrastructure, follicle and corpus luteum counts were assessed via hematoxylin and eosin (H&E) staining. Serum hormone levels were measured using enzyme-linked immunosorbent assay (ELISA). Nrf2/HO-1 pathway, stem cell, germ cell, and cell cycle biomarkers were analyzed by qPCR and Western blot. Cell viability was assessed by cell counting kit-8 (CCK-8) assay. Oxidative stress biomarkers were evaluated using flow cytometry and assay kits. Immunofluorescence was employed to detect and locate OSCs in the ovary, quantify the average fluorescence intensity, and identify OSCs. RESULTS: After ZGP treatment, rats with CTX-induced ovarian aging exhibited improved general condition, increased body weight, higher total ovarian weight to body weight ratio, and a restoration of the estrous cycle similar to the control group. Serum levels of estradiol (E2) and follicle stimulating hormone (FSH), two sex hormones, were also improved. Ovarian ultrastructure and follicle count at all stages showed improvement. Moreover, the viability and proliferation capacity of OSCs were enhanced following ZGP intervention. The Nrf2/HO-1 pathway was found to be down-regulated in CTX-induced aging ovarian OSCs. However, ZGP reversed this effect by activating the expression of Nrf2, HO-1, and NAD(P)H oxidoreductase 1 (NQO1), increasing the activity of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), and reducing the accumulation of malonaldehyde (MDA) and reactive oxygen species (ROS), thus restoring resistance to oxidative stress. Additionally, ZGP improved the cell cycle of OSCs, up-regulated the expression of Cyclin D1 and Cyclin E1, restored cell stemness, promoted proliferation, enhanced the expression of cell stemness markers octamer-binding transcription factor 4 (Oct4) and mouse VASA homolog (MVH), and down-regulated the expression of P21, thereby inhibiting apoptosis. The therapeutic effects of ZGP against oxidative stress and restoration of cell stemness were attenuated following inhibition of the Nrf2 signaling pathway using ML385. CONCLUSIONS: ZGP protected against CTX-induced ovarian aging by restoring normal ovarian function, alleviating oxidative stress in aging OSCs, promoting OSCs proliferation, and restoring their stemness in rats, possibly through regulating the Nrf2/HO-1 pathway.
Subject(s)
Drugs, Chinese Herbal , Oogonial Stem Cells , Ovary , Oxidative Stress , Signal Transduction , Animals , Female , Rats , Aging/drug effects , Cyclophosphamide , Drugs, Chinese Herbal/pharmacology , Heme Oxygenase (Decyclizing)/metabolism , Heme Oxygenase-1/metabolism , NF-E2-Related Factor 2/metabolism , Oogonial Stem Cells/drug effects , Ovary/drug effects , Ovary/metabolism , Ovary/pathology , Oxidative Stress/drug effects , Rats, Sprague-Dawley , Signal Transduction/drug effectsABSTRACT
Cell encapsulation technology, crucial for advanced biomedical applications, faces challenges in existing microfluidic and electrospray methods. Microfluidic techniques, while precise, can damage vulnerable cells, and conventional electrospray methods often encounter instability and capsule breakage during high-throughput encapsulation. Inspired by the transformation of the working state from unstable dripping to stable jetting triggered by local electric potential, this study introduces a superimposed electric field (SEF)-enhanced electrospray method for cell encapsulation, with improved stability and biocompatibility. Utilizing stiffness theory, the stability of the electrospray, whose stiffness is five times stronger under conical confinement, is quantitatively analyzed. The SEF technique enables rapid, continuous production of ≈300 core-shell capsules per second in an aqueous environment, significantly improving cell encapsulation efficiency. This method demonstrates remarkable potential as exemplified in two key applications: (1) a 92-fold increase in human-derived induced pluripotent stem cells (iPSCs) expansion over 10 d, outperforming traditional 2D cultures in both growth rate and pluripotency maintenance, and (2) the development of liver capsules for steatosis modeling, exhibiting normal function and biomimetic lipid accumulation. The SEF-enhanced electrospray method presents a significant advancement in cell encapsulation technology. It offers a more efficient, stable, and biocompatible approach for clinical transplantation, drug screening, and cell therapy.
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Programmed death-ligand 1 (PD-L1) has emerged as a promising therapeutic target for various cancers due to its crucial role in promoting tumor immune evasion. Here, we report a novel class of chroman-like small-molecule PD-L1 inhibitors exhibiting significant activity in inhibiting the PD-1/PD-L1 interaction. Employing a "ring-close" strategy for conformational restriction, we have achieved compound C27, which demonstrates superior PD-1/PD-L1 inhibitory activity compared to the positive control. Molecular dynamics simulation and binding free energy calculation predict that (R)-C27 with inhibitory activity surpassed (S)-C27. The experimental results from bioassay and X-ray structural analysis corroborate these findings. All these results collectively indicate that (R)-C27 is a promising lead compound deserving further exploration.
Subject(s)
B7-H1 Antigen , Chromans , Drug Design , Programmed Cell Death 1 Receptor , B7-H1 Antigen/antagonists & inhibitors , B7-H1 Antigen/metabolism , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Programmed Cell Death 1 Receptor/metabolism , Humans , Chromans/chemistry , Chromans/pharmacology , Molecular Dynamics SimulationABSTRACT
Large-scale hydrogen production by electrocatalytic water splitting still remains as a critical challenge due to the severe catalyst degradation during the oxygen evolution reaction (OER) in acidic media. In this study, we investigate the structural impacts on catalyst degradation behaviors using three iridium-based oxides, namely SrIrO3, Sr2IrO4, and Sr4IrO6 as model catalysts. These Ir oxides possess different connection configurations of [IrO6] octahedra units in their structure. Stable OER performance is observed on SrIrO3 and attributed to the edge-linked [IrO6] structure and rapid formation of a continuous IrOx layer on its surface, which functions not only as the "real" catalyst but also a shield preventing continuous cation leaching (with <1.0 at.% of Ir leaching). In comparison, both Sr2IrO4 and Sr4IrO6 catalysts demonstrate quick current fading with structure transformation to rutile IrO2 and formation of inconducive SrSO4 precipitates on surface, blocking the reactive sites. Nevertheless, over 60 at.% of Ir leaching is detected from the Sr4IrO6 catalyst due to its isolated [IrO6] structure configuration. Results of this work highlight the structural impacts on the catalyst stability in acidic OER conditions.
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Objective: Recent studies have shown that gene alternative splicing (AS) and long noncoding RNAs (lncRNAs) are involved in diabetes mellitus (DM) and its complications. Currently, myo-inositol (MI) is considered as effective for the treatment of insulin resistance and lipid metabolism disorders in diabetes patients. We hope to better explore the potential roles of gene AS and lncRNAs in liver glucose and lipid metabolism in diabetes, as well as the effects of myo-inositol treatment, through transcriptome analysis. Methods: This study analysed glucose and lipid metabolism-related biochemical indicators and liver HE staining in four groups of mice: the control group (Ctrl group), the diabetes group (DM group), the myo-inositol treatment group (MI group), and the metformin treatment group (Met group). The changes in relevant gene-regulated alternative splicing events (RASEs) and lncRNAs were analysed by RNA sequencing of liver tissue, and coexpression analysis and functional enrichment analysis were used to predict the possible lncRNAs and RASEs involved in liver glucose and lipid metabolism. Result: Metformin and myo-inositol alleviated insulin resistance, lipid metabolism disorders, and hepatic steatosis in diabetic mice. Transcriptome sequencing analysis revealed differential splicing events of genes related to lipid metabolism and differentially expressed lncRNAs (DElncRNAs). Six different lncRNAs and their potentially interacting splicing events were predicted. Conclusion: The present study revealed novel changes in RASEs and lncRNAs in the livers of diabetic mice following treatment with myo-inositol, which may shed light on the potential mechanisms by which myo-inositol delays and treats the progression of hepatic glucose and lipid metabolism in diabetes.
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Objective: Epilepsy is a common neurological disorder characterized by recurrent epilepsy episodes. As a non-pharmacological treatment, the ketogenic diet has been widely applied in treating epilepsy. However, the exact therapeutic mechanism of the ketogenic diet for epilepsy remains unclear. This study investigates the molecular mechanisms of the ketogenic diet in regulating fatty acid metabolism and activating the ADCY3-initiated cAMP signaling pathway to enhance neuronal inhibition and thereby treat epilepsy. Methods and results: Meta-analysis reveals that the ketogenic diet is superior to the conventional diet in treating epilepsy. Animal experiments demonstrate that the ketogenic diet is more effective than the conventional diet in treating epilepsy, with the best results achieved using the classic ketogenic diet. Transcriptome sequencing analysis identifies six essential genes, among which ADCY3 shows increased expression in the ketogenic diet. In vivo experiments confirm that the activation of the cAMP-PKA signaling pathway by ADCY3 enhances neuronal inhibition and improves epilepsy control. Conclusion: Clinical observations indicate that the ketogenic diet improves patient epilepsy episodes by regulating the ADCY3-initiated cAMP signaling pathway.
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Background: Epilepsy is one of the most prevalent serious brain disorders globally, impacting over 70 million individuals. Observational studies have increasingly recognized the impact of plasma lipidome on epilepsy. However, establishing a direct causal link between plasma lipidome and epilepsy remains elusive due to inherent confounders and the complexities of reverse causality. This study aims to investigate the causal relationship between specific plasma lipidome and epilepsy, along with their intermediary mediators. Methods: We conducted a two-sample Mendelian randomization (MR) and mediation MR analysis to evaluate the causal effects of 179 plasma lipidomes and epilepsy, with a focus on the inflammatory cytokine as a potential mediator based on the genome-wide association study. The primary methodological approach utilized inverse variance weighting, complemented by a range of other estimators. A set of sensitivity analyses, including Cochran's Q test, I 2 statistics, MR-Egger intercept test, MR-PRESSO global test and leave-one-out sensitivity analyses was performed to assess the robustness, heterogeneity and horizontal pleiotropy of results. Results: Our findings revealed a positive correlation between Phosphatidylcholine (18:1_18:1) levels with epilepsy risk (OR = 1.105, 95% CI: 1.036-1.178, p = 0.002). Notably, our mediation MR results propose Tumor necrosis factor ligand superfamily member 12 levels (TNFSF12) as a mediator of the relationship between Phosphatidylcholine (18,1_18:1) levels and epilepsy risk, explaining a mediation proportion of 4.58% [mediation effect: (b = 0.00455, 95% CI: -0.00120-0.01030), Z = 1.552]. Conclusion: Our research confirms a genetic causal relationship between Phosphatidylcholine (18:1_18:1) levels and epilepsy, emphasizing the potential mediating role of TNFSF12 and provide valuable insights for future clinical investigations into epilepsy.
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OBJECTIVES: The objective of this study is to identify dual-target inhibitors against EGFR/c-Met through virtual screening, dynamic simulation, and biological activity evaluation. This endeavor is aimed at overcoming the challenge of drug resistance induced by L858R/T790M mutants. METHODS: Active structures were gathered to construct sets of drug molecules. Next, property filtering was applied to the drug structures within the compound library. Active compounds were then identified through virtual screening and cluster analysis. Subsequently, we conducted MTT antitumor activity evaluation and kinase inhibition assays for the active compounds to identify the most promising candidates. Furthermore, AO staining and JC-1 assays were performed on the selected compounds. Ultimately, the preferred compounds underwent molecular docking and molecular dynamics simulation with the EGFR and c-Met proteins, respectively. RESULT: The IC50 of T13074 was determined as 2.446 µM for EGFRL858R/T790M kinase and 7.401 nM for c-Met kinase, underscoring its potential in overcoming EGFRL858R/T790M resistance. Additionally, T13074 exhibited an IC50 of 1.93 µM on the H1975 cell. Results from AO staining and JC-1 assays indicated that T13074 induced tumor cell apoptosis in a concentration-dependent manner. Notably, the binding energy between T13074 and EGFR protein was found to be -90.329 ± 16.680 kJ/mol, while the binding energy with c-Met protein was -139.935 ± 17.414 kJ/mol. CONCLUSION: T13074 exhibited outstanding antitumor activity both in vivo and in vitro, indicating its potential utility as a dual-target EGFR/c-Met inhibitor. This suggests its promising role in overcoming EGFR resistance induced by the L858R/T790M mutation.
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BACKGROUND: α-l-Fucose confers unique functions for fucose-containing biomolecules such as human milk oligosaccharides. α-l-Fucosidases can serve as desirable tools in the application of fucosylated saccharides. Discovering novel α-l-fucosidases and elucidating their enzyme properties are always worthy tasks. RESULTS: A GH95 family α-l-fucosidase named Afc95A_Wf was cloned from the genome of the marine bacterium Wenyingzhuangia fucanilytica and expressed in Escherichia coli. It exhibited maximum activity at 40 °C and pH 7.5. Afc95A_Wf defined a different substrate specificity among reported α-l-fucosidases, which was capable of hydrolyzing α-fucoside in CNP-fucose, Fucα1-2Galß1-4Glc and Galß1-4(Fucα1-3)Glc, and showed a preference for α1,2-fucosidic linkage. It adopted Asp residue in the amino acid sequence at position 391, which was distinct from the previously acknowledged residue of Asn. The predicted tertiary structure and site-directed mutagenesis revealed that Asp391 participates in the catalysis of Afc95A_Wf. The differences in the substrate specificity and catalytic site shed light on that Afc95A_Wf adopted a novel mechanism in catalysis. CONCLUSION: A GH95 family α-l-fucosidase (Afc95A_Wf) was cloned and expressed. It showed a cleavage preference for α1,2-fucosidic linkage to α1,3-fucosidic linkage. Afc95A_Wf demonstrated a different substrate specificity and a residue at an important catalytic site compared with known GH95 family proteins, which revealed the occurrence of diversity on catalytic mechanisms in the GH95 family. © 2024 Society of Chemical Industry.