Developing non-precious-metal electrocatalysts that can operate with a low overpotential at a high current density for industrial application is challenging. Heterogeneous bimetallic phosphides have attracted much interest. Despite high hydrogen evolution reaction (HER) performance, the ordinary oxygen evolution reaction (OER) performance hinders their practical use. Herein, it is shown that Fe-doping reverses and enlarges the interfacial electrical field at the heterojunction, turning the H intermediate favorable binding sites for HER into O intermediate favorable sites for OER. Specifically, the self-supported heterojunction catalysts on nickel foam (CoP@Ni2P/NF and Fe-CoP@Fe-Ni2P/NF) are readily synthesized. They only require the overpotentials of 266 and 274 mV to drive a large current density of 1000 mA cm-2 (j1000) for HER and OER, respectively. Furthermore, a water splitting cell equipped with these electrodes only requires a voltage of 1.724 V to drive j1000 with excellent durability, demonstrating the potential of industrial application. This work offers new insights on interfacial engineering for heterojunction catalysts.
The conformation of molecules and materials is crucial in determining their properties and applications. Here, this work explores the reversible transformation between two distinct conformational isomers in metal nanoclusters. This work demonstrates the successful manipulation of a controllable and reversible isomerization of Au18SR14 within an aqueous solution through two distinct methods: ethanol addition and pH adjustment. The initial driver is the alteration of the solution environment, leading to the aggregation of Au18SR14 protected by ligands with smaller steric hindrance. At the atomic level, the folding mode of the unique Au4SR5 staple underpins the observed structural transformation. The reversal of staple conformation leads to color shifting between green and orange-red, and tailors a second emission peak at 725 nm originating from charge transfer from the thiolate to the Au9 core. This work not only deepens the understanding of the surface structure and dual-emission of metal nanoparticles, but also enhances the comprehension of their isomerization.
Objectives: To investigate the effect of different designs of movable parts and prosthetic materials on the stress distribution of supporting tissues in mandibular free end dentition defects using three-dimensional finite element analysis of digital Roach attachments. Material and methods: A 3D model of a patient with Kennedy class I mandibular edentulous conditions was generated, and twelve prosthesis models were applied, combining two designs of removable parts and six types of CAD/CAM restorative materials with different elastic modulus (conventional zirconia, ultra-translucent zirconia, Polyetheretherketone (PEEK), Lithium disilicate, Nanoceramic resin, and resin composite (Paradigm MZ100, 3 M ESPE)). The stress distribution of abutment periodontal ligament, edentulousmucosa, and junction of attachment were analyzed using finite element analysis. Results: The stress value of the buccal neck of the periodontal ligament and the maximum compressive stress of the distal periodontal ligament of the design with clasp arms were higher than those without clasp arms, while the stress on the junction of attachment and the displacement of the mucosa in the edentulous area were smaller. Restorative materials with high elastic modulus, such as conventional zirconia and ultra-translucent zirconia, are recommended to be used as the fixed part of Roach attachment. Conclusion: CAD/CAM Roach attachments with clasp arms are recommended for the protection of mucosal soft tissue. Restorative materials with high elastic modulus, such as conventional zirconia and ultra-translucent zirconia, are recommended as the fixed part of Roach attachment for patients with free end defect of mandibular dentition. Clinical significance: This study provides references for the design with clasp arms and the selection of clinical fixed-movable prosthetic materials. Clinicians should consider the design of attachments and selection of appropriate manufacturing materials carefully to avoid negative impacts on patients' periodontal support tissues.
Background: The emerging mutants of the 2019-nCoV coronavirus are posing unprecedented challenges to the pandemic prevention. A thorough, understanding of the mutational characterization responsible for the pathogenic mechanisms of mutations in 2019-nCoV-Spike is indispensable for developing effective drugs and new vaccines. Methods: We employed computational methods and viral infection assays to examine the interaction pattern and binding affinity between ACE2 and both single- and multi-mutants of the Spike proteins. Results: Using data from the CNCB-NGDC databank and analysis of the 2019-nCoV-Spike/ACE2 interface crystal structure, we identified 31 amino acids that may significantly contribute to viral infectivity. Subsequently, we performed molecular dynamics simulations for 589 single-mutants that emerged from the nonsynonymous substitutions of the aforementioned 31 residues. Ultimately, we discovered 8 single-mutants that exhibited significantly higher binding affinities (<-65.00 kcal/mol) to ACE2 compared with the wild-type Spike protein (-55.07 kcal/mol). The random combination of these 8 single-mutants yielded 184 multi-mutants, of which 60 multi-mutants exhibit markedly enhanced binding affinities (<-65.00 kcal/mol). Moreover, the binding free energy analyses of all 773 mutants (including 589 single- and 184 multi-mutants) revealed that Y449R and S494R had a synergistic effect on the binding affinity with other mutants, which were confirmed by virus infection assays of six randomly selected multi-mutants. More importantly, the findings of virus infection assay further validated a strong association between the binding free energy of Spike/ACE2 complex and the viral infectivity. Conclusions: These findings will greatly contribute to the future surveillance of viruses and rational design of therapeutics.
The emergence of SARS-CoV-2-Spike mutants not only enhances viral infectivity but also lead to treatment failure. Gaining a comprehensive understanding of the molecular binding mode between the mutant SARS-CoV-2-Spike and human ACE2 receptor is crucial for therapeutic development against this virus. Building upon our previous predictions and verifications regarding heightened viral infectivity of six potential SARS-CoV-2-Spike mutants, this study aims to further investigate the potential disruption of the interaction between these mutants and ACE2 by quercetin, a Chinese herbal compound. Molecular docking and dynamics simulations results reveal that the binding sites of quercetin particularly enriched around a specific "cavity" at the interface of Spike/ACE2 complex, indicating a favorable region for quercetin to interfere with Spike/ACE2 interaction. Virus infection assay confirms that quercetin not only attenuates wild-type virus infectivity but also suppresses the infectivity of all six tested SARS-CoV-2-Spike mutants. Therefore, quercetin represents a promising therapeutic candidate against both wild-type and potential future variants of SARS-CoV-2 exhibiting high viral infectivity.
Aims: Reactive oxygen species (ROS) play a vital role in conveying the cytotoxicity and resistance of most chemotherapy drugs. Therefore, gaining a comprehensive understanding of the intricate activities against oxidative stress in cancer cells may provide valuable insights into the discovery of common mechanisms underlying chemoresistance. Results: We identified a novel long noncoding RNA (lncRNA), designated fluorouracil-associated transcript-1 (FUAT1), as a key nongenetic player involved in ROS-mediated intrinsic chemoresistance by employing a unique screening strategy based on transcriptome sequencing (RNA-Seq) technology. To investigate the precise role of the FUAT1 regulatory axis in chemoresistance, we conducted a series of in vitro and in vivo assays including gain/loss-of-function and rescue experiments. Mechanistically, our findings revealed that FUAT1 upregulates Tensin 4 (TNS4) by sponging miR-140-5p, which allows gastric cancer cells to survive chemotherapy by inhibiting ROS-mediated apoptosis. Clinically, we observed that the FUAT1/TNS4 regulatory axis is negatively associated with overall survival and progression-free survival among gastric and colon cancer patients treated with 5-fluorouracil adjuvant chemotherapy. Innovation: We devised a novel screening strategy distinct from conventional approaches using drug-resistant strains. Through this approach, we identified the previously unrecognized lncRNA FUAT1/TNS4 axis that plays a critical role in ROS-mediated intrinsic chemoresistance. Conclusions: Our findings shed light on fundamental adaptive mechanisms employed by cancer cells to respond to chemotherapy and provide new insights into developing strategies aiming at overcoming chemoresistance.
Objective: Nowadays, primary liver carcinoma (PLC) is one of the major contributors to the global cancer burden, and China has the highest morbidity and mortality rates in the world. As a well-known Chinese herbal medicine (CHM) prescription, Huatan Sanjie Granules (HSG) has been used clinically for many years to treat PLC with remarkable efficacy, but the underlying mechanism of action remains unclear. Methods: A clinical cohort study was conducted to observe the overall survival of PLC patients with vs. without oral administration of HSG. Meanwhile, the BATMAN-TCM database was used to retrieve the potential active ingredients in the six herbs of HSG and their corresponding drug targets. PLC-related targets were then screened through the Gene Expression Omnibus (GEO) database. The protein-protein interaction (PPI) network of targets of HSG against PLC was constructed using Cytoscape software. The cell function assays were further carried out for verification. Results: The results of the cohort study showed that the median survival time of PLC patients exposed to HSG was 269 days, which was 23 days longer than that of the control group (HR, 0.62; 95% CI, 0.38-0.99; p = 0.047). In particular, the median survival time of Barcelona Clinic Liver Cancer stage C patients was 411 days in the exposure group, which was 137 days longer than that in the control group (HR, 0.59; 95% CI, 0.35-0.96; p = 0.036). Meanwhile, the enrichment analysis result for the obtained PPI network consisting of 362 potential core therapeutic targets suggest that HSG may inhibit the growth of liver cancer (LC) cells by blocking the PI3K-Akt/MAPK signaling pathways. Furthermore, the above prediction results were verified by a series of in vitro assays. Specifically, we found that the expressions TP53 and YWHA2, the targets of the hepatitis B virus signaling pathway, were significantly affected by HSG. Conclusion: HSG shows promising therapeutic efficacy in the adjuvant treatment of PLC.
BACKGROUND: Immunocheckpoint inhibitors (ICIs) have been widely used in the clinical treatment of lung cancer. Although clinical studies and trials have shown that patients can benefit significantly after PD-1/PD-L1 blocking therapy, less than 20% of patients can benefit from ICIs therapy due to tumor heterogeneity and the complexity of immune microenvironment. Several recent studies have explored the immunosuppression of PD-L1 expression and activity by post-translational regulation. Our published articles demonstrate that ISG15 inhibits lung adenocarcinoma progression. Whether ISG15 can enhance the efficacy of ICIs by modulating PD-L1 remains unknown. METHODS: The relationship between ISG15 and lymphocyte infiltration was identified by IHC. The effects of ISG15 on tumor cells and T lymphocytes were assessed using RT-qPCR and Western Blot and in vivo experiments. The underlying mechanism of PD-L1 post-translational modification by ISG15 was revealed by Western blot, RT-qPCR, flow cytometry, and Co-IP. Finally, we performed validation in C57 mice as well as in lung adenocarcinoma tissues. RESULTS: ISG15 promotes the infiltration of CD4+ T lymphocytes. In vivo and in vitro experiments demonstrated that ISG15 induces CD4+ T cell proliferation and invalidity and immune responses against tumors. Mechanistically, we demonstrated that the ubiquitination-like modifying effect of ISG15 on PD-L1 increased the modification of K48-linked ubiquitin chains thus increasing the degradation rate of glycosylated PD-L1 targeting proteasomal pathway. The expression of ISG15 and PD-L1 was negatively correlated in NSCLC tissues. In addition, reduced accumulation of PD-L1 by ISG15 in mice also increased splenic lymphocyte infiltration as well as promoted cytotoxic T cell infiltration in the tumor microenvironment, thereby enhancing anti-tumor immunity. CONCLUSIONS: The ubiquitination modification of PD-L1 by ISG15 increases K48-linked ubiquitin chain modification, thereby increasing the degradation rate of glycosylated PD-L1-targeted proteasome pathway. More importantly, ISG15 enhanced the sensitivity to immunosuppressive therapy. Our study shows that ISG15, as a post-translational modifier of PD-L1, reduces the stability of PD-L1 and may be a potential therapeutic target for cancer immunotherapy.
Adenocarcinoma of Lung , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Animals , Mice , B7-H1 Antigen/metabolism , Carcinoma, Non-Small-Cell Lung/drug therapy , Cell Line, Tumor , Lung Neoplasms/pathology , Tumor Microenvironment , Ubiquitins
Huangqi Guizhi Wuwu Decoction (HGWD), as a classic Chinese herbal decoction, has been widely used in treating various diseases for hundreds of years. However, systematically elucidating its mechanisms of action remains a great challenge to the field. In this study, taking advantage of the network pharmacology approach, we discovered a potential new use of HGWD for patients with colon cancer (CC). Our in vivo result showed that orally administered HGWD markedly inhibited the growth of CC xenografts in mice. The subsequent enrichment analyses for the core therapeutic targets revealed that HGWD could affect multiple biological processes involving CC growth, such as metabolic reprogramming, apoptosis and immune regulation, through inhibiting multiple cell survival-related signalings, including MAPK and PI3K-AKT pathways. Notably, these in silico analysis results were most experimentally verified by a series of in vitro assays. Furthermore, our results based on serum metabolomics showed that the lipid metabolic pathways, including fatty acid biosynthesis and cholesterol metabolism, play key roles in delivery of the anti-CC effect of HGWD on tumor-bearing mice, and that cytochrome P450 family 2 subfamily E member 1 (CYP2E1) is a potential therapeutic target. Together, our integrated approach reveals a therapeutic effect of HGWD on CC, providing a valuable insight into developing strategies to predict and interpret the mechanisms of action for Chinese herbal decoctions.
Background: Patients with different karyotypes had different prognosis in t(8;21) acute myeloid leukemia (AML). Cytarabine (Ara-C) plays an important role as consolidation therapy in t(8;21) AML. T(8;21) AML patients with different karyotypes responded differently to post-remission therapy with Ara-C. However, the optimum dose of Ara-C in patients with different karyotypes remains unclear. Methods: From January 2002 to September 2018, a total of 188 younger adult (14-60 years) patients with t(8;21) AML were enrolled in this retrospective study. Cytogenetic analysis and aberration descriptions followed the International System for Human Cytogenetic Nomenclature. All the patients achieved first complete remission (CR1) after induction chemotherapy. Patients received low-dose Ara-C [LDAC (<1 g/m2)], intermediate-dose Ara-C [IDAC (1-1.5 g/m2)], or high-dose Ara-c [HiDAC (2-3 g/m2)] regimens as consolidation therapy after CR1. All patients were followed for survival or relapse until death, or study completion. We analyzed the prognosis of LDAC, IDAC, and HiDAC regimens as consolidation therapy in patients with different karyotypes. The primary endpoint was overall survival (OS) and the secondary endpoint was relapse-free survival (RFS). Results: The results showed IDAC significantly improved OS compared with LDAC [hazard rate (HR) =0.55, P=0.0375] when the clinical factors were adjusted. However, no significant difference between HiDAC and IDAC was found. Subgroup analysis further showed that the OS advantage of IDAC was focused on patients with additional cytogenetic abnormalities, including loss of X chromosome (-X), del(9q), or complex karyotype (group B, HR =0.21, P=0.0125), but not on patients with t(8;21)-only or additional loss of Y chromosome (-Y) cytogenetics (group A, HR =0.77, P=0.4804) in multivariate analysis. Similarly, better OS was shown after IDAC than LDAC consolidation in patients in group B, whether they received allogeneic hematopoietic stem cell transplantation (allo-HSCT) or not, but not in group A. Conclusions: IDAC was suitable for patients with additional -X, del(9q), or complex karyotype, while LDAC might be sufficient for patients with t(8;21)-only or additional -Y cytogenetics. It suggested that t(8;21) AML patients with different karyotypes should use different consolidation regimens.
BACKGROUND: Colon cancer (CC) ranks the second highest mortality rate among malignant tumors worldwide, and the current mainstream treatment regimens are not very effective. The unique efficacy of Chinese herb medicine (CHM) for cancer has recently attracted increasing attention. Cinnamomi Ramulus (CR), as a classic CHM, has been widely used in the treatment of a variety of diseases for hundreds of years in China, but its specific pharmacological mechanism against CC needs to be fully evaluated. METHODS: TCMSP and China National Knowledge Infrastructure database were utilized to predict the candidate ingredients of CR, and TCMSP and SwissTargetPrediction database were also employed to predict the drug targets of the candidate ingredients from CR. We subsequently evaluated the therapeutic effect of CR by orally administrating it on CC-bearing mice. Next, we further identified the potential CC-related targets by using Gene Expression Omnibus (GEO) database. Based on these obtained targets, the drug/disease-target PPI networks were constructed using Bisogenet plugin of Cytoscape. The potential core therapeutic targets were then identified through topological analysis using CytoNCA plugin. GO and KEGG enrichment analyses were performed to predict the underlying mechanism of CR against CC. Furthermore, these in silico analysis results were validated by a series of cellular functional and molecular biological assays. UPLC-MS/MS method and molecular docking analysis were employed to identify the potential key components from CR. RESULTS: In this study, we firstly found that CR has potential therapeutic effect on cancer. Then, oral administration of CR could inhibit the growth of CC cells in C57BL/6 mice, while inhibiting the viability and motility of CC cells in vitro. We obtained 111 putative core therapeutic targets of CR. Subsequent enrichment analysis on these targets showed that CR could induce apoptosis and cell cycle arrest in CC cells by blocking Akt/ERK signaling pathways, which was further experimentally verified. We identified 5 key components from the crude extract of CR, among which taxifolin was found most likely to be the key active component against CC. CONCLUSIONS: Our results show that CR as well as its active component taxifolin holds great potential in treatment of CC.
ABBREVIATIONS: CC: Closeness centrality; OS: Osteosarcoma; TCM: Traditional Chinese medicine; NSCLC: Non-small cell lung cancer; DC: Degree centrality; CHM: Chinese herb medicine; BC: Betweenness centrality.
Bone Neoplasms , Carcinoma, Non-Small-Cell Lung , Fallopia japonica , Lung Neoplasms , Osteosarcoma , ErbB Receptors , Humans , Proto-Oncogene Proteins c-akt , Signal Transduction
The blood-brain barrier (BBB) of Drosophila comprises a thin epithelial layer of subperineural glia (SPG), which ensheath the nerve cord and insulate it against the potassium-rich hemolymph by forming intercellular septate junctions (SJs). Previously, we identified a novel Gi/Go protein-coupled receptor (GPCR), Moody, as a key factor in BBB formation at the embryonic stage. However, the molecular and cellular mechanisms of Moody signaling in BBB formation and maturation remain unclear. Here, we identify cAMP-dependent protein kinase A (PKA) as a crucial antagonistic Moody effector that is required for the formation, as well as for the continued SPG growth and BBB maintenance in the larva and adult stage. We show that PKA is enriched at the basal side of the SPG cell and that this polarized activity of the Moody/PKA pathway finely tunes the enormous cell growth and BBB integrity. Moody/PKA signaling precisely regulates the actomyosin contractility, vesicle trafficking, and the proper SJ organization in a highly coordinated spatiotemporal manner. These effects are mediated in part by PKA's molecular targets MLCK and Rho1. Moreover, 3D reconstruction of SJ ultrastructure demonstrates that the continuity of individual SJ segments, and not their total length, is crucial for generating a proper paracellular seal. Based on these findings, we propose that polarized Moody/PKA signaling plays a central role in controlling the cell growth and maintaining BBB integrity during the continuous morphogenesis of the SPG secondary epithelium, which is critical to maintain tissue size and brain homeostasis during organogenesis.
Drosophila Proteins/genetics , Drosophila melanogaster/physiology , Receptors, G-Protein-Coupled/genetics , Signal Transduction , Animals , Blood-Brain Barrier/physiology , Drosophila Proteins/metabolism , Drosophila melanogaster/genetics , Receptors, G-Protein-Coupled/metabolism
Minichromosome maintenance proteins (MCMs) are considered to be essential factors coupling DNA replication to both cell cycle progression and checkpoint regulation. Previous studies have shown that dysregulation of MCMs are implicated in tumorigenesis of lung cancer. However, the distinct expression/mutation patterns and prognostic values of MCMs in lung cancer have yet to be systematically elucidated. In the present study, we analyzed the transcriptional levels, mutations, and prognostic value of MCM1-10 in non-small cell lung cancer (NSCLC) patients using multiple bioinformatics tools, including ONCOMINE, GEPIA, Kaplan-Meier Plotter, cBioPortal, and GESA. The analysis results from GEPIA dataset showed that MCM2/4/10 was significantly high expressed in both lung adenocarcinoma (LUAD) and squamous cell lung carcinomas (LUSCs). Meanwhile, the expression levels of MCM2/4/6/7/8 were associated with advanced tumor stages. Subsequent survival analysis using the Kaplan-Meier Plotter indicated that high expression levels of MCM1/2/3/4/5/6/7/8/10 were associated with worse overall survival (OS), while high expression level of MCM9 predicted better OS in these patients. Furthermore, we experimentally validated overexpression of MCM2 and MCM4 in NSCLC, thus the results from this study support a view that they may serve as potential prospective biomarkers to identify high-risk subgroups of NSCLC patients.
Lung cancer (LC) ranks the leading cause of cancer-related death worldwide, due partially to the unsatisfactory therapeutic effect of the mainstream treatment. Alternatively, Chinese herb medicine (CHM) offers a bright perspective for treating complex diseases. Mahuang Decoction (MHD), a classic CHM formula, has been widely used in treating respiratory diseases in China for centuries, but its action mechanism has yet to be fully investigated. In this study, we first systemically explore the action mechanism of MHD by using network pharmacology and bioinformatic analysis tools, which uncovered a potential "new use of old drug" for MHD in cancer treatment. The therapeutic effect of MHD on LC was then validated by oral administration of MHD in the immunodeficient mice bearing xenografted LC tumors. To better understand the pharmacological activity of MHD against LC, we next constructed a drug/disease-target PPI network composed of 252 putative core therapeutic targets of MHD using Cytoscape. The subsequent enrichment analysis for these targets suggested that MHD could affect the apoptosis and cell cycle of LC cells via impeding Akt/ERK signaling pathways. Notably, these in silico analysis results were further validated by a series of cellular functional and molecular biological assays. Thus, our results show that MHD holds a great potential in LC treatment.
The outbreak of COVID-19 raises an urgent need for the therapeutics to contain the emerging pandemic. However, no effective treatment has been found for SARS-CoV-2 infection to date. Here, we identified puerarin (PubChem CID: 5281807), quercetin (PubChem CID: 5280343) and kaempferol (PubChem CID: 5280863) as potential compounds with binding activity to ACE2 by using Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). Molecular docking analysis showed that puerarin and quercetin exhibit good binding affinity to ACE2, which was validated by surface plasmon resonance (SPR) assay. Furthermore, SPR-based competition assay revealed that puerarin and quercetin could significantly affect the binding of viral S-protein to ACE2 receptor. Notably, quercetin could also bind to the RBD domain of S-protein, suggesting not only a receptor blocking, but also a virus neutralizing effect of quercetin on SARS-CoV-2. The results from network pharmacology and bioinformatics analysis support a view that quercetin is involved in host immunomodulation, which further renders it a promising candidate against COVID-19. Moreover, given that puerarin is already an existing drug, results from this study not only provide insight into its action mechanism, but also propose a prompt application of it on COVID-19 patients for assessing its clinical feasibility.
Due to its in-plane structural anisotropy and highly polymorphic nature, borophene has been shown to form a diverse set of linear superlattice structures that are not observed in other two-dimensional materials. Here, we show both theoretically and experimentally that concentric superlattice structures can also be realized in borophene via the energetically preferred self-assembly of coherent twin boundaries. Since borophene twin boundaries do not require the creation of additional lattice defects, they are exceptionally low in energy and thus easier to nucleate and even migrate than grain boundaries in other two-dimensional materials. Due to their high mobility, borophene twin boundaries naturally self-assemble to form novel phases consisting of periodic concentric loops of filled boron hexagons that are further preferred energetically by the rotational registry of borophene on the Ag(111) surface. Compared to defect-free borophene, concentric superlattice borophene phases are predicted to possess enhanced mechanical strength and localized electronic states. Overall, these results establish defect-mediated self-assembly as a pathway to unique borophene structures and properties.
Danggui Sini Decoction (DSD), a classic Chinese herb medicine (CHM) formula, has been used to treat various diseases in China for centuries. However, it remains challenging to reveal its mechanism of action through conventional pharmacological methods. Here, we first explored the mechanism of action of DSD with the assistance of network pharmacology and bioinformatic analysis tools, and found a potential therapeutic effect of DSD on cancer. Indeed, our in vivo experiment demonstrated that oral administration of DSD could significantly inhibit the growth of xenografted gastric cancer (GC) on mice. The subsequent enrichment analyses for 123 candidate core targets evacuated from the drug/disease-target protein-protein interaction network showed that DSD could affect the key biological processes involving the survival and growth of GC cells, such as apoptosis and cell cycle, and the disturbance of these biological processes is likely attributed to the simultaneous inhibition of multiple signaling pathways, including PI3K/Akt, MAPK, and p53 pathways. Notably, these in silico results were further validated by a series of cellular functional and molecular biological assays in vitro. Moreover, molecular docking analysis suggested an important role of MCM2 in delivering the pharmacological activity of DSD against GC. Together, these results indicate that our network pharmacology and bioinformatics-guided approach is feasible and useful in exploring not only the mechanism of action, but also the "new use" of the old CHM formula.
Retinal neovascularization (RNV) is a common pathology of blinding proliferative retinopathies. The current treatments to RNV, however, are hindered by limited efficacy, side effects, and drug resistance. A naturally-occurring cytokine in retina that is amicable to immune system and possesses robust anti-neovascular function would facilitate to overcome the hurdles. In this study, retinas from a mouse model of oxygen-induced retinopathy (OIR) underwent a protein array to screen the naturally-occurring cytokines that may antagonize RNV. Among the 62 angiogenesis-associated cytokines, platelet factor 4 (Pf4) stood out with the most prominent upregulation and statistical significance. Moreover, an intravitreal injection of mouse Pf4 demonstrated dramatic anti-vaso-obliteration and anti-neovascularization effects dose dependently in the OIR model; whereas human PF4 inhibited the proliferation, migration, and tubulogenesis of monkey retinal vascular endothelial cells treated with VEGF and TNF-α. These previously undescribed angiostatic effects of PF4 in OIR retinas and retinal vascular endothelial cells support translation of this naturally-occurring chemokine into a therapeutic modality to RNV supplementary to the anti-VEGFs. Mechanistically, a phosphorylation array and western blots indicated that downregulation of proline-rich Akt substrate of 40 kDa (Pras40) and its phosphorylation were necessary for Pf4's anti-neovascular effects in the OIR retinas. Indeed, overexpression of the wildtype Pras40 and the mutant version with deficient phosphorylation abolished and mimicked the Pf4's angiostatic effects in the OIR retinas, respectively. The similar effects were also observed in vitro. This study, for the first time, links PF4's anti-RNV function to an intracellular signaling molecule PRAS40 and its phosphorylation.
Adaptor Proteins, Signal Transducing/antagonists & inhibitors , Oxygen/metabolism , Phosphoproteins/antagonists & inhibitors , Platelet Factor 4/antagonists & inhibitors , Retina/metabolism , Retinal Neovascularization/metabolism , Retinopathy of Prematurity/metabolism , Adult , Aged , Aged, 80 and over , Animals , Disease Models, Animal , Endothelial Cells/metabolism , Female , Humans , Male , Mice , Mice, Inbred C57BL , Middle Aged , Phosphorylation/physiology , Signal Transduction/physiology , Vascular Endothelial Growth Factor A/metabolism
As a popular Chinese herbal medicine (CHM), polygonum cuspidatum is widely used to treat various diseases in China. However, its biological function and action mechanism have yet to be systematically explored. In the present study, we first identified 14 potential active ingredients of polygonum cuspidatum using the TCMSP server and then conducted an in silico target prediction for these ingredients using PharmMapper. The subsequent KEGG pathway enrichment analysis of the 57 identified potential targets revealed that they were closely associated with cancer and gynecological disorders. Furthermore, a protein-protein interaction network of these targets was constructed using STRING and Cytoscape, through which 11 core targets were excavated according to degree, a key topological parameter. Meanwhile, we developed a novel formula, in which the "R value" is determined by average shortest path length and closeness centrality, two other key topological parameters, to evaluate the reliability of these predicted core targets. Intriguingly, among the top 10 core targets excavated using this new formula, 7 overlapped with the former 11 core targets, showing a good consistency in these core targets between the different prediction algorithms. Next, 7 ingredients were identified/validated from the crude extract of polygonum cuspidatum using UPLC-MS/MS. Noteworthy, 6 potential targets predicted for these 7 ingredients overlapped with the 7 core targets excavated from the previous in silico analyses. Further molecular docking and druggability analyses suggested that polydatin may play a pivotal role in manifesting the therapeutic effects of polygonum cuspidatum. Finally, we carried out a series of cell functional assays, which validated the anti-proliferative effects of polygonum cuspidatum on gynecological cancer cells, thus demonstrating our network pharmacology approach is reliable and powerful enough to guide the CHM mechanism study.
