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1.
Cancer Sci ; 115(2): 369-384, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38050654

RESUMO

In gastric cancer (GC), the liver is a common organ for distant metastasis, and patients with gastric cancer with liver metastasis (GCLM) generally have poor prognosis. The mechanism of GCLM is unclear. Invadopodia are special membrane protrusions formed by tumor cells that can degrade the basement membrane and ECM. Herein, we investigated the role of invadopodia in GCLM. We found that the levels of invadopodia-associated proteins were significantly higher in liver metastasis than in the primary tumors of patients with GCLM. Furthermore, GC cells could activate hepatic stellate cells (HSCs) within the tumor microenvironment of liver metastases through the secretion of platelet-derived growth factor subunit B (PDGFB). Activated HSCs secreted hepatocyte growth factor (HGF), which activated the MET proto-oncogene, MET receptor of GC cells, thereby promoting invadopodia formation through the PI3K/AKT pathway and subsequently enhancing the invasion and metastasis of GC cells. Therefore, cross-talk between GC cells and HSCs by PDGFB/platelet derived growth factor receptor beta (PDGFRß) and the HGF/MET axis might represent potential therapeutic targets to treat GCLM.


Assuntos
Neoplasias Hepáticas , Podossomos , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Proteínas Proto-Oncogênicas c-sis/metabolismo , Células Estreladas do Fígado/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Hepáticas/patologia , Transdução de Sinais , Microambiente Tumoral
2.
BMC Med ; 22(1): 96, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443977

RESUMO

BACKGROUND: There is a lack of effective therapeutic strategies for amyotrophic lateral sclerosis (ALS); therefore, drug repurposing might provide a rapid approach to meet the urgent need for treatment. METHODS: To identify therapeutic targets associated with ALS, we conducted Mendelian randomization (MR) analysis and colocalization analysis using cis-eQTL of druggable gene and ALS GWAS data collections to determine annotated druggable gene targets that exhibited significant associations with ALS. By subsequent repurposing drug discovery coupled with inclusion criteria selection, we identified several drug candidates corresponding to their druggable gene targets that have been genetically validated. The pharmacological assays were then conducted to further assess the efficacy of genetics-supported repurposed drugs for potential ALS therapy in various cellular models. RESULTS: Through MR analysis, we identified potential ALS druggable genes in the blood, including TBK1 [OR 1.30, 95%CI (1.19, 1.42)], TNFSF12 [OR 1.36, 95%CI (1.19, 1.56)], GPX3 [OR 1.28, 95%CI (1.15, 1.43)], TNFSF13 [OR 0.45, 95%CI (0.32, 0.64)], and CD68 [OR 0.38, 95%CI (0.24, 0.58)]. Additionally, we identified potential ALS druggable genes in the brain, including RESP18 [OR 1.11, 95%CI (1.07, 1.16)], GPX3 [OR 0.57, 95%CI (0.48, 0.68)], GDF9 [OR 0.77, 95%CI (0.67, 0.88)], and PTPRN [OR 0.17, 95%CI (0.08, 0.34)]. Among them, TBK1, TNFSF12, RESP18, and GPX3 were confirmed in further colocalization analysis. We identified five drugs with repurposing opportunities targeting TBK1, TNFSF12, and GPX3, namely fostamatinib (R788), amlexanox (AMX), BIIB-023, RG-7212, and glutathione as potential repurposing drugs. R788 and AMX were prioritized due to their genetic supports, safety profiles, and cost-effectiveness evaluation. Further pharmacological analysis revealed that R788 and AMX mitigated neuroinflammation in ALS cell models characterized by overly active cGAS/STING signaling that was induced by MSA-2 or ALS-related toxic proteins (TDP-43 and SOD1), through the inhibition of TBK1 phosphorylation. CONCLUSIONS: Our MR analyses provided genetic evidence supporting TBK1, TNFSF12, RESP18, and GPX3 as druggable genes for ALS treatment. Among the drug candidates targeting the above genes with repurposing opportunities, FDA-approved drug-R788 and AMX served as effective TBK1 inhibitors. The subsequent pharmacological studies validated the potential of R788 and AMX for treating specific ALS subtypes through the inhibition of TBK1 phosphorylation.


Assuntos
Aminopiridinas , Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Reposicionamento de Medicamentos , Análise da Randomização Mendeliana , Proteínas Serina-Treonina Quinases/genética
3.
Mol Cell Biochem ; 479(4): 941-950, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37256443

RESUMO

Colorectal cancer (CRC) is becoming one of the most common cancers overworld, which causes a high rate of death in patients. circRNAs are non-coding RNAs(ncRNAs), which have been reported to be involved in the development of many cancers, including CRC. However, the exact mechanism that how circRNAs function through in CRC remains unclear. In this study, we firstly used GEO database and bioinformatic methods to identify the significant changed circRNAs, with circSKA3 being the most significantly upregulated circRNAs in CRC tissues. PCR results further confirmed higher expression of circSKA3 in CRC patients. CCK-8, scratch, and transwell assays indicated that circSKA3 could promote the proliferation, migration, and invasion of CRC cell lines for cell detection. Dual-luciferase assays were carried out to detect the downstream targets of circSKA3, and a binding site between circSKA3 and miR-1238 was identified and miR-1238 could also combine with YTHDF2. Overexpression of YTHDF2 rescued the decreased cell proliferation, migration, and invasion caused by miR-1238 overexpression. RIP assay further indicated that YTHDF2 could decrease the methylation of STAT5A. In summary, our study found that circSKA3 was upregulated in CRC tissues comparing with normal tissues. circSKA3 could increase the expression ofYTHDF2 through sponging miR-1238 to decrease the methylation of STAT5A, which could provide a novel target for CRC treatment.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Proliferação de Células , Metilação
4.
Immunology ; 170(2): 167-179, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37132045

RESUMO

Mucosa-associated invariant T cells (MAIT) are a class of innate-like T lymphocytes mainly presenting CD8+ phenotype with a semi-invariant αß T-cell receptor, which specifically recognises MR1-presented biosynthetic derivatives of riboflavin synthesis produced by various types of microbiomes. As innate-like T lymphocytes, MAIT can be activated by a variety of cytokines, leading to immediate immune responses to infection and tumour cues. As an organ that communicates with the external environment, the digestive tract, especially the gastrointestinal tract, contains abundant microbial populations. Communication between MAIT and local microbiomes is important for the homeostasis of mucosal immunity. In addition, accumulating evidence suggests changes in the abundance and structure of the microbial community during inflammation and tumorigenesis plays a critical role in disease progress partly through their impact on MAIT development and function. Therefore, it is essential for the understanding of MAIT response and their interaction with microbiomes in the digestive tract. Here, we summarised MAIT characteristics in the digestive tract and its alteration facing inflammation and tumour, raising that targeting MAIT can be a candidate for treatment of gastrointestinal diseases.


Assuntos
Células T Invariantes Associadas à Mucosa , Neoplasias , Humanos , Citocinas , Trato Gastrointestinal , Inflamação
5.
Int J Cancer ; 153(4): 709-722, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-36752642

RESUMO

Immunotherapy, especially with immune checkpoint inhibitors (ICIs), has shown advantages in cancer treatment and is a new hope for patients who have failed multiline therapy. However, in colorectal cancer (CRC), the benefit is limited to a small subset of patients with microsatellite instability-high (MSI-H) or mismatch repair-deficient (dMMR) metastatic CRC (mCRC). In addition, 45% to 60% of dMMR/MSI-H mCRC patients showed primary or acquired resistance to ICIs. This means that these patients may have potential unknown pathways mediating immune escape. Almost all mismatch repair-proficient (pMMR) or microsatellite-stable (MSS) mCRC patients do not benefit from ICIs. In this review, we discuss the mechanisms of action of ICIs and their current status in CRC. We then discuss the mechanisms of primary and acquired resistance to ICIs in CRC. Finally, we discuss promising therapeutic strategies to overcome resistance to ICIs in the clinic.


Assuntos
Neoplasias Colorretais , Inibidores de Checkpoint Imunológico , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Reparo de Erro de Pareamento de DNA , Imunoterapia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Instabilidade de Microssatélites
6.
Phys Rev Lett ; 131(22): 225101, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101383

RESUMO

Transient electron dynamics near the interface of counterstreaming plasmas at the onset of a relativistic collisionless shock (RCS) is investigated using particle-in-cell simulations. We identify a slingshotlike injection process induced by the drifting electric field sustained by the flowing focus of backward-moving electrons, which is distinct from the well-known stochastic acceleration. The flowing focus signifies the plasma kinetic transition from a preturbulent laminar motion to a chaotic turbulence. We find a characteristic correlation between the electron dynamics in the slingshot acceleration and the photon emission features. In particular, the integrated radiation from the RCS exhibits a counterintuitive nonmonotonic dependence of the photon polarization degree on the photon energy, which originates from a polarization degradation of relatively high-energy photons emitted by the slingshot-injected electrons. Our results demonstrate the potential of photon polarization as an essential information source in exploring intricate transient dynamics in RCSs with relevance for Earth-based plasma and astrophysical scenarios.

7.
PLoS Biol ; 18(3): e3000631, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32150533

RESUMO

Endocytic recycling of internalized transmembrane proteins is essential for many important physiological processes. Recent studies have revealed that retromer-related Sorting Nexin family (SNX)-Bin/Amphiphysin/Rvs (BAR) proteins can directly recognize cargoes like cation-independent mannose 6-phosphate receptor (CI-MPR) and Insulin-like growth factor 1 receptor (IGF1R); however, it remains poorly understood how SNX-BARs select specific cargo proteins and whether they recognize additional ligands. Here, we discovered that the binding between SNX-BARs and CI-MPR or IGF1R is mediated by the phox-homology (PX) domain of SNX5 or SNX6 and a bipartite motif, termed SNX-BAR-binding motif (SBM), in the cargoes. Using this motif, we identified over 70 putative SNX-BAR ligands, many of which play critical roles in apoptosis, cell adhesion, signal transduction, or metabolite homeostasis. Remarkably, SNX-BARs could cooperate with both SNX27 and retromer in the recycling of ligands encompassing the SBM, PDZ-binding motif, or both motifs. Overall, our studies establish that SNX-BARs function as a direct cargo-selecting module for a large set of transmembrane proteins transiting the endosome, in addition to their roles in phospholipid recognition and biogenesis of tubular structures.


Assuntos
Proteoma/metabolismo , Receptor IGF Tipo 2/metabolismo , Nexinas de Classificação/química , Nexinas de Classificação/metabolismo , Motivos de Aminoácidos , Sítios de Ligação , Transporte Biológico , Simulação por Computador , Técnicas de Inativação de Genes , Células HeLa , Humanos , Domínios Proteicos , Proteoma/química , Receptor IGF Tipo 2/química , Semaforinas/metabolismo , Nexinas de Classificação/genética
8.
BMC Gastroenterol ; 23(1): 201, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37296427

RESUMO

PURPOSE: Stoma site incisional hernia (SSIH) is a common complication, but its incidence and risk factors are not well known. The objective of this study is to explore the incidence and risk factors of SSIH and build a predictive model. METHODS: We performed a multicenter retrospective analysis on the patients who underwent enterostomy closure from January 2018 to August 2020. Patient's general condition, perioperative, intraoperative, and follow-up information was collected. The patients were divided into control group (no occurrence) and observation group (occurrence) according to whether SSIH occurred. Univariate and multivariate analysis were used to evaluate the risk factors of SSIH, following which we constructed a nomogram for SSIH prediction. RESULTS: One hundred fifty-six patients were enrolled in the study. The incidence of SSIH was 24.4% (38 cases), of which 14 were treated with hernia mesh repair, and the others were treated with conservative treatment. Univariate and multivariate analysis showed that age ≥ 68 years (OR 1.045, 95% CI 1.002 ~ 1.089, P = 0.038), colostomy (OR 2.913, 95% CI 1.035 ~ 8.202, P = 0.043), BMI ≥ 25 kg/m2 (OR 1.181, 95% CI 1.010 ~ 1.382, P = 0.037), malignant tumor (OR 4.838, 95% CI 1.508 ~ 15.517, P = 0.008) and emergency surgery (OR 5.327, 95% CI 1.996 ~ 14.434, P = 0.001) are the independent risk factors for SSIH. CONCLUSIONS: Based on the results, a predictive model for the occurrence of SSIH was constructed to screen high-risk groups of SSIH. For patients at high risk for SSIH, how to deal with the follow-up and prevent the occurrence of SSIH is worth further exploration.


Assuntos
Enterostomia , Hérnia Incisional , Humanos , Idoso , Hérnia Incisional/epidemiologia , Hérnia Incisional/etiologia , Hérnia Incisional/prevenção & controle , Estudos Retrospectivos , Incidência , Enterostomia/efeitos adversos , Fatores de Risco
9.
Phytother Res ; 37(10): 4587-4606, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37353982

RESUMO

Ferroptosis, an iron-dependent cell death characterized by lethal lipid peroxidation, is involved in chronic obstructive pulmonary disease (COPD) pathogenesis. Therefore, ferroptosis inhibition represents an attractive strategy for COPD therapy. Herein, we identified natural flavonoid scutellarein as a potent ferroptosis inhibitor for the first time, and characterized its underlying mechanisms for inhibition of ferroptosis and COPD. In vitro, the anti-ferroptotic activity of scutellarein was investigated through CCK8, real-time quantitative polymerase chain reaction (RT-qPCR), Western blotting, flow cytometry, and transmission electron microscope (TEM). In vivo, COPD was induced by lipopolysaccharide (LPS)/cigarette smoke (CS) and assessed by changes in histopathological, inflammatory, and ferroptotic markers. The mechanisms were investigated by RNA-sequencing (RNA-seq), electrospray ionization mass spectra (ESI-MS), local surface plasmon resonance (LSPR), drug affinity responsive target stability (DARTS), cellular thermal shift assay (CETSA), and molecular dynamics. Our results showed that scutellarein significantly inhibited Ras-selective lethal small molecule (RSL)-3-induced ferroptosis and mitochondria injury in BEAS-2B cells, and ameliorated LPS/CS-induced COPD in mice. Furthermore, scutellarein also repressed RSL-3- or LPS/CS-induced lipid peroxidation, GPX4 down-regulation, and overactivation of Nrf2/HO-1 and JNK/p38 pathways. Mechanistically, scutellarein inhibited RSL-3- or LPS/CS-induced Fe2+ elevation through directly chelating Fe2+ . Moreover, scutellarein bound to the lipid peroxidizing enzyme arachidonate 15-lipoxygenase (ALOX15), which resulted in an unstable state of the catalysis-related Fe2+ chelating cluster. Additionally, ALOX15 overexpression partially abolished scutellarein-mediated anti-ferroptotic activity. Our findings revealed that scutellarein alleviated COPD by inhibiting ferroptosis via directly chelating Fe2+ and interacting with ALOX15, and also highlighted scutellarein as a candidate for the treatment of COPD and other ferroptosis-related diseases.


Assuntos
Apigenina , Ferroptose , Doença Pulmonar Obstrutiva Crônica , Camundongos , Animais , Araquidonato 15-Lipoxigenase/metabolismo , Lipopolissacarídeos , Doença Pulmonar Obstrutiva Crônica/patologia , Quelantes de Ferro , Ferro
10.
Environ Geochem Health ; 45(7): 5323-5341, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37131113

RESUMO

Dashan Village area is one of the representative areas in China with high selenium concentration in the natural environment. A total of 133 topsoil samples have been collected in the Dashan Village area to explore the potential toxic elements (PTEs) background concentrations in soils under different land-use types for a comprehensive PTEs risk assessment (arsenic, cadmium, chromium, copper, mercury, nickel, lead, selenium and zinc). The results show that the geometric mean concentrations of As, Cr, Cu, Hg, Ni, Pb, Se and Zn found in the soil of the Dashan Village area were lower than the control standard for soil contamination risk in agricultural land. However, the geometric mean concentrations of Cd exceeded their corresponding standard values. For different land-use types, geometric mean concentrations of As, Cd, Cu, Hg, Ni and Pb in the arable soils were higher than in woodland soils and tea garden soils. Based on the potential ecological risk assessment, the woodland, arable and tea garden were at low-risk levels. Cadmium posed the highest ecological risk, while the other PTEs were of low risk in soils. Multiple statistical analyses and geostatistical analysis indicated that the concentrations of Cr, Ni, Pb, Cu, Zn and Se originated mainly from natural sources, while the concentrations of Cd, As and Hg could be influenced by anthropogenic activities. These results provide scientific support for the safe utilization and ecological sustainability of selenium-rich land resources.


Assuntos
Mercúrio , Metais Pesados , Selênio , Poluentes do Solo , Solo , Metais Pesados/toxicidade , Metais Pesados/análise , Cádmio/análise , Selênio/análise , Cobre/análise , Chumbo/análise , Mercúrio/análise , Medição de Risco , China , Chá , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Monitoramento Ambiental/métodos
11.
Bioorg Med Chem ; 66: 116811, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35576655

RESUMO

Acute inflammatory diseases, such as sepsis, are life-threatening illnesses. Regulating the α7 nicotinic acetylcholine receptor (α7 nAchR)-mediated signaling may be a promising strategy to treat sepsis. Diarylheptanoids have long been found to exhibit anti-inflammatory properties. However, the possible mechanism of diarylheptanoids has rarely been investigated. In this study, we isolated and synthesized 49 diarylheptanoids and analogues and evaluated their anti-inflammatory activities. Among them, compounds 28 and 40 markedly blocked lipopolysaccharide (LPS)-induced production of nitric oxide (NO), interleukin-1ß (IL-1ß) and interleukin-6 in murine RAW264.7 cells. Furthermore, compounds 28 and 40 also effectively attenuated LPS-induced sepsis, acute lung injury, and cytokines release in vivo. Mechanistically, compounds 28 and 40 significantly induced phosphorylation of janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling and suppression of nuclear factor-κB (NF-κB) pathway. Furthermore, blocking α7 nAchR could effectively abolish compounds 28 and 40-mediated activation of JAK2-STAT3 signaling as well as inhibition of NF-κB activation and NO production in LPS-exposed RAW264.7 cells. Collectively, our findings have identified a new diarylheptanoid, compound 28, as an agonist of α7 nAchR-JAK2-STAT3 signaling, which can be potentially developed as a valuable candidate for the treatment of sepsis, and provide a new lead structure for the development of anti-inflammatory agents targeting α7 nAchR-JAK2-STAT3 signaling.


Assuntos
Janus Quinase 2 , Sepse , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Diarileptanoides/farmacologia , Janus Quinase 2/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos , Camundongos , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Sepse/tratamento farmacológico , Sepse/metabolismo
12.
World J Surg Oncol ; 20(1): 282, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36058930

RESUMO

BACKGROUND: The clinical application of robotic-assisted gastrectomy remains controversial, especially as clinical studies of this operation navigated by carbon nanoparticle suspension injection (CNSI) have not been conducted. This study aims to assess the perioperative safety and efficacy of CNSI-guided robotic-assisted gastrectomy in patients with gastric cancer by focusing on short-term outcomes. METHODS: A retrospective analysis of patients who underwent CNSI-guided laparoscopic or robotic-assisted gastrectomy with a pathological diagnosis of gastric cancer was conducted. Data on demographics, surgical management, clinical-pathological results and short-term outcomes were compared among the groups. RESULTS: A total of 126 eligible patients were separated into the robotic-assisted gastrectomy (RAG) group (n = 16) and the laparoscopic gastrectomy (LG) group (n = 110) in total. The operation time of the RAG group is longer than the LG group (p = 0.0000). When it comes to perioperative and short-term complications, there exists no statistical difference between the two groups. CONCLUSION: The time required for CNSI-guided robotic-assisted gastrectomy is longer than that for CNSI-guided laparoscopic gastrectomy. CNSI-guided robotic-assisted gastrectomy is safe and effective.


Assuntos
Laparoscopia , Nanopartículas , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Carbono , Gastrectomia/métodos , Humanos , Laparoscopia/métodos , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
13.
Proc Natl Acad Sci U S A ; 116(45): 22598-22608, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31624125

RESUMO

Pontocerebellar hypoplasia (PCH) is a group of neurological disorders that affect the development of the brain, in particular, the pons and cerebellum. Homozygous mutations of TBC1D23 have been found recently to lead to PCH; however, the underlying molecular mechanisms remain unclear. Here, we show that the crystal structure of the TBC1D23 C-terminal domain adopts a Pleckstrin homology domain fold and selectively binds to phosphoinositides, in particular, PtdIns(4)P, through one surface while binding FAM21 via the opposite surface. Mutation of key residues of TBC1D23 or FAM21 selectively disrupts the endosomal vesicular trafficking toward the Trans-Golgi Network. Finally, using the zebrafish model, we show that PCH patient-derived mutants, impacting either phosphoinositide binding or FAM21 binding, lead to abnormal neuronal growth and brain development. Taken together, our data provide a molecular basis for the interaction between TBC1D23 and FAM21, and suggest a plausible role for PtdIns(4)P in the TBC1D23-mediating endosome-to-TGN trafficking pathway. Defects in this trafficking pathway are, at least partially, responsible for the pathogenesis of certain types of PCH.


Assuntos
Doenças Cerebelares/metabolismo , Endossomos/metabolismo , Proteínas Ativadoras de GTPase/química , Proteínas Ativadoras de GTPase/metabolismo , Animais , Doenças Cerebelares/genética , Endossomos/genética , Proteínas Ativadoras de GTPase/genética , Células HeLa , Humanos , Mutação , Proteínas de Ligação a Fosfato/química , Proteínas de Ligação a Fosfato/genética , Proteínas de Ligação a Fosfato/metabolismo , Ligação Proteica , Domínios Proteicos , Transporte Proteico , Peixe-Zebra , Rede trans-Golgi/genética , Rede trans-Golgi/metabolismo
14.
BMC Microbiol ; 21(1): 164, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078263

RESUMO

BACKGROUND: The rate of fluoroquinolone (FQ) resistance among carbapenem-resistant Klebsiella pneumoniae (CRKP) is high. The present study aimed to investigate the distribution of fluoroquinolone resistance determinants in clinical CRKP isolates associated with bloodstream infections (BSIs). RESULTS: A total of 149 BSI-associated clinical CRKP isolates collected from 11 Chinese teaching hospitals from 2015 to 2018 were investigated for the prevalence of fluoroquinolone resistance determinants, including plasmid-mediated quinolone resistance (PMQR) genes and spontaneous mutations in the quinolone resistance-determining regions (QRDRs) of the gyrA and parC genes. Among these 149 clinical CRKP isolates, 117 (78.5%) exhibited resistance to ciprofloxacin. The GyrA substitutions (Ser83 → IIe/Phe) and (Asp87 → Gly/Ala) were found among 112 (75.2%) of 149 isolates, while the substitution (Ser80 → IIe) of ParC was found in 111 (74.5%) of the 149 isolates. In total, 70.5% (105/149) of the CRKP isolates had at least two mutations within gyrA as well as a third mutation in parC. No mutations in the QRDRs were found in 31 ciprofloxacin susceptible CRKP isolates. Eighty-nine (56.9%) of 149 were found to carry PMQR genes including qnrS1 (43.0%), aac(6')-Ib-cr (16.1%), qnrB4 (6.0%), qnrB2 (2.7%), and qnrB1 (1.3%). Nine isolates contained two or more PMQR genes, with one carrying four [aac(6')-Ib-cr, qnr-S1, qnrB2, and qnrB4]. The co-existence rate of PMQR determinants and mutations in the QRDRs of gyrA and parC reached 68.5% (61/89). Seventy-four (83.1%, 74/89) PMQR-positive isolates harbored extended-spectrum beta-lactamase (ESBL)-encoding genes. Multilocus sequence typing (MLST) analysis demonstrated that the ST11 was the most prevalent STs in our study. CONCLUSIONS: Mutations in the QRDRs of gyrA and parC were the key factors leading to the high prevalence of fluoroquinolone resistance among BSI-associated CRKP. The co-existence of PMQR genes and mutations in the QRDRs can increase the resistance level of CRKP to fluoroquinolones in clinical settings. ST11 CRKP isolates with identical QRDR substitution patterns were found throughout hospitals in China.


Assuntos
Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana , Fluoroquinolonas/farmacologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Sepse/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , China , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/metabolismo , Tipagem de Sequências Multilocus , Plasmídeos/genética , Plasmídeos/metabolismo
15.
J Pharmacol Sci ; 146(4): 206-215, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34116734

RESUMO

AIMS: To investigate the effect of dencichine on osteoclastogenesis in vivo and in vitro. METHODS: RANKL-induced osteoclastogenesis were treated with different concentrations of dencichine. Pit forming assays were applied to evaluate the degree of bone resorption. Osteoclastogenic markers were detected by real-time quantitative PCR (RT-qPCR) and Western blot. Micro CT was conducted to investigate the effects of dencichine on osteoclastogenesis in ovariectomized (OVX) mice. RESULTS: Dencichine suppressed osteoclastogenesis through the inhibition of phosphorylation of p65, p50 (NF-κB pathway), p38, ERK and JNK (MAPKs pathway) in vitro. Furthermore, dencichine inhibited the function of osteoclasts in a dose-dependent manner. In addition, the expression levels of the nuclear factor of activated T cells 1 (NFATc1) and osteoclastogenesis markers were decreased by dencichine, including MMP-9, Cathepsin K (CTSK), Tartrate-Resistant Acid Phosphatase (TRAP), C-FOS, dendritic cell specific transmembrane protein (DC-STAMP). In vivo data proved that dencichine alleviated ovariectomy-induced bone loss and osteoclastogenesis in mice. CONCLUSION: Our results demonstrate that dencichine alleviates OVX-induced bone loss in mice and inhibits RANKL-mediated osteoclastogenesis via inhibition of NF-κB and MAPK pathways in vitro, suggesting that dencichine might serve as a promising candidate for treatment of bone loss diseases, including PMOP and rheumatoid arthritis.


Assuntos
Diamino Aminoácidos/farmacologia , Diamino Aminoácidos/uso terapêutico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteoporose Pós-Menopausa/etiologia , Osteoporose Pós-Menopausa/prevenção & controle , Ovariectomia/efeitos adversos , Ligante RANK/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Animais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Osteoporose Pós-Menopausa/genética , Células RAW 264.7
16.
J Immunol ; 202(6): 1669-1673, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30728212

RESUMO

Group 2 innate lymphoid cells (ILC2) are tissue-resident, long-lived innate effector cells implicated in allergy and asthma. Upon activation, mature ILC2 rapidly secrete large amounts of type-2 cytokines and other effector molecules. The molecular pathways that drive ILC2 activation are not well understood. In this study, we report that the transcriptional controller core binding factor ß (CBFß) is required for ILC2 activation. Deletion or inhibition of CBFß did not impair the maintenance of ILC2 at homeostasis but abolished ILC2 activation during allergic airway inflammation. Treatment with CBFß inhibitors prevented ILC2-mediated airway hyperresponsiveness in a mouse model of acute Alternaria allergen inhalation. CBFß promoted expression of key ILC2 genes at both transcriptional and translational levels. CBF transcriptional complex directly bound to Il13 and Vegfa promoters and enhancers, and controlled gene transcription. CBFß further promoted ribosome biogenesis and enhanced gene translation in activated ILC2. Together, these data establish an essential role for CBFß in ILC2 activation.


Assuntos
Subunidade beta de Fator de Ligação ao Core/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/imunologia , Ativação Linfocitária/imunologia , Linfócitos/imunologia , Animais , Hipersensibilidade/imunologia , Camundongos , Camundongos Knockout
17.
J Nat Prod ; 84(11): 2808-2821, 2021 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-34726063

RESUMO

Chromatographic fractionation of Sigesbeckia glabrescens led to the identification of 10 new sesquiterpene lactones, named siegesbeckialides I-O (1-7) and glabrescones A-C (8-10), along with 14 known analogues. An anti-inflammatory activity assay showed that siegesbeckialide I (1) most potently inhibited LPS-induced NO production in RAW264.7 murine macrophages. Furthermore, siegesbeckialide I suppressed the protein expression of iNOS and COX2, as well as the release of PGE2, IL-1ß, IL-6, and TNF-α in LPS-stimulated RAW264.7 cells. Mechanistically, siegesbeckialide I directly binds to inhibitors of IKKα/ß and suppresses their phosphorylation. This leads to the inhibition of IKKα/ß-mediated phosphorylation and degradation of inhibitor α of NF-κB (IκBα), as well as the activation of NF-κB signaling.


Assuntos
Anti-Inflamatórios/farmacologia , Asteraceae/química , Quinase I-kappa B/antagonistas & inibidores , Lactonas/farmacologia , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Células HEK293 , Humanos , Lactonas/química , Lactonas/isolamento & purificação , Lipopolissacarídeos/farmacologia , Camundongos , NF-kappa B/fisiologia , Fosforilação , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
18.
Bioorg Chem ; 112: 104845, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33812268

RESUMO

Steroidal alkaloids (1-11), including one new 24-hydroxylated cevanine-type steroidal alkaloid, named yibeinone F (1), were isolated from the bulbs of Fritillaria pallidiflora Schrenk. Their structures were elucidated by analyses of extensive spectroscopic data and comparison of the NMR data with those reported previously, and the structures of compounds 1, 7 and 11 were further confirmed by X-ray single crystal diffraction analyses. The anti-inflammatory effects of all the isolated alkaloids were evaluated in LPS-activated RAW264.7 macrophages. Among them, compounds 9 (stenanzine) and 10 (hapepunine) showed significant inhibitory effects against LPS-induced NO production with IC50 values of 8.04 µM and 20.85 µM, respectively. Furthermore, compound 9 effectively inhibited the release of cytokines such as interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and prostaglandin E2 (PGE2), and suppressed the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX2) in LPS-stimulated RAW264.7 cells. Further experiments revealed the underlying mechanism that 9 blocked LPS-induced phosphorylation and degradation of inhibitor-α of nuclear transcription factor κB (IκBα) and c-Jun N-terminal kinase (JNK) in RAW264.7 cells. Taken together, compound 9 may be a valuable candidate for the treatment of inflammatory diseases.


Assuntos
Alcaloides/farmacologia , Anti-Inflamatórios/farmacologia , Fritillaria/química , Esteroides/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Conformação Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Células RAW 264.7 , Esteroides/química , Esteroides/isolamento & purificação , Relação Estrutura-Atividade
19.
BMC Surg ; 21(1): 309, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253214

RESUMO

BACKGROUND: Small bowel obstruction (SBO) is common and usually requires surgical intervention. Intestinal plication is a traditional but critical strategy for SBO in certain scenarios. This study is to compare the short-term and long-term outcome between internal and external plications in the management of SBO. METHODS: All patients receiving intestinal plication in our hospital were retrospectively collected. Short-term outcome including postoperative complications, reoperation, postoperative ICU stay, starting day of liquid diet and postoperative hospitalization, as well as long-term outcome including recurrence of obstruction, readmission, reoperation and death were compared between groups. Gut function at annual follow-up visits was evaluated as well. RESULTS: Nine internal and 11 external candidates were recruited into each group. The major causes of plication were adhesive obstruction, abdominal cocoon, volvulus and intussusception. Lower incidence of postoperative complication (p = 0.043) and shorter postoperative hospitalization (p = 0.049) was observed in internal group. One patient receiving external plication died from anastomosis leakage. During the 5-year follow-up period, the readmission rate was low in both groups (22.2 % vs. 9.1 %), and none of patients required reoperation or deceased. None of patients exhibited gut dysfunction, and all patients restored normal gut function after 4 years. Patients in external group demonstrated accelerated recovery of gut function after surgery. CONCLUSIONS: This study compares short-term and long-term outcome of patients receiving internal or external intestinal plication. We suggest a conservative attitude toward external plication strategy. Surgical indication for intestinal plication is critical and awaits future investigations.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Obstrução Intestinal , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Intestino Delgado/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Reoperação , Estudos Retrospectivos
20.
J Biol Chem ; 294(46): 17471-17486, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594861

RESUMO

Constitutive activation of signal transducer and activator of transcription 3 (STAT3) occurs in ∼70% of human cancers, and STAT3 is regarded as one of the most promising targets for cancer therapy. However, specific direct STAT3 inhibitors remain to be developed. Oridonin is an ent-kaurane plant-derived diterpenoid with anti-cancer and anti-inflammatory activities. Here, using an array of cell-based and biochemical approaches, including cell proliferation and apoptosis assays, pulldown and reporter gene assays, site-directed mutagenesis, and molecular dynamics analyses, we report that a thiazole-derived oridonin analogue, CYD0618, potently and directly inhibits STAT3. We found that CYD0618 covalently binds to Cys-542 in STAT3 and suppresses its activity through an allosteric effect, effectively reducing STAT3 dimerization and nuclear translocation, as well as decreasing expression of STAT3-targeted oncogenes. Remarkably, CYD0618 not only strongly inhibited growth of multiple cancer cell lines that harbor constitutive STAT3 activation, but it also suppressed in vivo tumor growth via STAT3 inhibition. Taken together, our findings suggest Cys-542 as a druggable site for selectively inhibiting STAT3 and indicate that CYD0618 represents a promising lead compound for developing therapeutic agents against STAT3-driven diseases.


Assuntos
Antineoplásicos/farmacologia , Diterpenos do Tipo Caurano/farmacologia , Neoplasias/tratamento farmacológico , Fator de Transcrição STAT3/antagonistas & inibidores , Regulação Alostérica/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/uso terapêutico , Feminino , Humanos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Neoplasias/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Fator de Transcrição STAT3/metabolismo , Tiazóis/química , Tiazóis/farmacologia , Tiazóis/uso terapêutico
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