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1.
J Biol Chem ; 300(3): 105741, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340793

RESUMO

Type VI secretion systems (T6SS) are bacterial macromolecular complexes that secrete effectors into target cells or the extracellular environment, leading to the demise of adjacent cells and providing a survival advantage. Although studies have shown that the T6SS in Pseudomonas aeruginosa is regulated by the Quorum Sensing system and second messenger c-di-GMP, the underlying molecular mechanism remains largely unknown. In this study, we discovered that the c-di-GMP-binding adaptor protein PA0012 has a repressive effect on the expression of the T6SS HSI-I genes in P. aeruginosa PAO1. To probe the mechanism by which PA0012 (renamed TssZ, Type Six Secretion System -associated PilZ protein) regulates the expression of HSI-I genes, we conducted yeast two-hybrid screening and identified HinK, a LasR-type transcriptional regulator, as the binding partner of TssZ. The protein-protein interaction between HinK and TssZ was confirmed through co-immunoprecipitation assays. Further analysis suggested that the HinK-TssZ interaction was weakened at high c-di-GMP concentrations, contrary to the current paradigm wherein c-di-GMP enhances the interaction between PilZ proteins and their partners. Electrophoretic mobility shift assays revealed that the non-c-di-GMP-binding mutant TssZR5A/R9A interacts directly with HinK and prevents it from binding to the promoter of the quorum-sensing regulator pqsR. The functional connection between TssZ and HinK is further supported by observations that TssZ and HinK impact the swarming motility, pyocyanin production, and T6SS-mediated bacterial killing activity of P. aeruginosa in a PqsR-dependent manner. Together, these results unveil a novel regulatory mechanism wherein TssZ functions as an inhibitor that interacts with HinK to control gene expression.


Assuntos
Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Pseudomonas aeruginosa , Transcrição Gênica , Sistemas de Secreção Tipo VI , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Imunoprecipitação , Mutação , Regiões Promotoras Genéticas , Ligação Proteica , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Piocianina/metabolismo , Percepção de Quorum , Sistemas do Segundo Mensageiro , Técnicas do Sistema de Duplo-Híbrido , Sistemas de Secreção Tipo VI/genética , Sistemas de Secreção Tipo VI/metabolismo
2.
Biochem Biophys Res Commun ; 696: 149483, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38219484

RESUMO

Highly cytotoxic maytansine derivatives are widely used in targeted tumor delivery. Structure-activity studies published earlier suggested the C9 carbinol to be a key element necessary to retain the potency. However, in 1984 a patent was published by Takeda in which the synthesis of 9-thioansamitocyn (AP3SH) was described and its activity in xenograft models was shown. In this article we summarize the results of an extended study of the anti-tumor properties of AP3SH. Like other maytansinoids, it induces apoptosis and arrests the cell cycle in the G2/M phase. It is metabolized in liver microsomes predominately by C3A4 isoform and doesn't inhibit any CYP isoforms except CYP3A4 (midazolam, IC50 7.84 µM). No hERG inhibition, CYP induction or mutagenicity in Ames tests were observed. AP3SH demonstrates high antiproliferative activity against 25 tumor cell lines and tumor growth inhibition in U937 xenograft model. Application of AP3SH as a cytotoxic payload in drug delivery system was demonstrated by us earlier.


Assuntos
Antineoplásicos , Maitansina , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Ciclo Celular , Divisão Celular
3.
Hepatobiliary Pancreat Dis Int ; 23(3): 257-264, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37903711

RESUMO

BACKGROUND: Our clinical practice of laparoscopic liver resection (LLR) had achieved better short-term and long-term benefits for patients with hepatocellular carcinoma (HCC) over open liver resection (OLR), but the underlying mechanisms are not clear. This study was to find out whether systemic inflammation plays an important role. METHODS: A total of 103 patients with early-stage HCC under liver resection were enrolled (LLR group, n = 53; OLR group, n = 50). The expression of 9 inflammatory cytokines in patients at preoperation, postoperative day 1 (POD1) and POD7 was quantified by Luminex Multiplex assay. The relationships of the cytokines and the postoperative outcomes were compared between LLR and OLR. RESULTS: Seven of the circulating cytokines were found to be significantly upregulated on POD1 after LLR or OLR compared to their preoperative levels. Compared to OLR, the POD1 levels of granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-6 (IL-6), IL-8, and monocyte chemoattractant protein-1 (MCP-1) in the LLR group were significantly lower. Higher POD1 levels of these cytokines were significantly correlated with longer operative time and higher volume of blood loss during operation. The levels of these cytokines were positively associated with postoperative liver injury, and the length of hospital stay. Importantly, a high level of IL-6 at POD1 was a risk factor for HCC recurrence and poor disease-free survival after liver resection. CONCLUSIONS: Significantly lower level of GM-CSF, IL-6, IL-8, and MCP-1 after liver resection represented a milder systemic inflammation which might be an important mechanism to offer better short-term and long-term outcomes in LLR over OLR.


Assuntos
Carcinoma Hepatocelular , Laparoscopia , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Neoplasias Hepáticas/patologia , Citocinas , Interleucina-6 , Interleucina-8 , Estudos Retrospectivos , Complicações Pós-Operatórias/etiologia , Hepatectomia/efeitos adversos , Laparoscopia/efeitos adversos , Inflamação , Tempo de Internação
4.
BMC Cancer ; 23(1): 203, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869304

RESUMO

BACKGROUND: With the application of immune checkpoint inhibitors (ICIs) in cancer treatment, more and more attention has been paid to checkpoint inhibitor-related pneumonitis (CIP), which requires a better understanding of its clinical characteristics and therapeutic effects. METHODS: The clinical and imaging data of 704 patients with non-small cell lung cancer (NSCLC) who received immunotherapy were analyzed retrospectively; the clinical characteristics of CIP were summarized, and the therapeutic regimens and effects of the patients were summarized. RESULTS: 36 CIP patients were included in the research. The most common clinical symptoms were cough, shortness of breath and fever. The CT manifestations were summarized as follows: Organizing pneumonia (OP) in 14 cases (38.9%), nonspecific interstitial pneumonia (NSIP) in 14 cases (38.9%), hypersensitiviy pneumonitis(HP) in 2 cases (6.3%), diffuse alveolar damage in 1 case (3.1%) and atypical imaging manifestations in 5 cases (13.9%). 35 cases received glucocorticoid therapy, 6 patients were treated with gamma globulin and 1 patient was treated with tocilizumab. There were no deaths in CIP G1-2 patients and 7 deaths occured in CIP G3-4 patients. 4 patients were treated again with ICIs. CONCLUSION: We found that glucocorticoid 1-2 mg/kg was effective for most patients with moderate to severe CIP, and a few patients with hormone insensitivity needed early immunosuppressive therapy. A few patients can be rechallenged with ICIs, but CIP recurrence needs to be closely monitored.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pneumonia , Humanos , Glucocorticoides , Estudos Retrospectivos
5.
Pancreatology ; 23(7): 767-776, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37661465

RESUMO

BACKGROUND: IgG4-related autoimmune pancreatitis (AIP) is considered to be a T cell-mediated autoimmune disease. However, CD8+ T cells have only received brief mention, and have yet to be completely studied. The study aimed to investigate the expression of signaling lymphocytic activation molecule family 7 (SLAMF7) on CD8+ T cells and the features of SLAMF7+CD8+ T cells in MRL/Mp mice with AIP. METHODS: A murine model of AIP was established by intraperitoneal injection with polyinosinic:polycytidylic acid (poly I:C) for 8 weeks. Dexamethasone treatment was daily administrated for the last 2 weeks during a 6-week course of poly I:C. SLAMF7 expression on CD8+ T cells in the spleen and pancreas was detected by flow cytometry. Granzyme B (GZMB) and cytokines including IFN-γ, TNF-α, and IL-2, were monitored in an in vitro T cell activation assay. Dexamethasone suppression assays were performed to downregulate SLAMF7 expression on T cells upon T cell receptor stimulation. RESULTS: AIP in MRL/Mp mice was induced by repeated intraperitoneal administration of poly I:C and CD8+ T cells were increased in the inflamed pancreas. SLAMF7+CD8+ T cells were elevated in the spleen and pancreas of AIP mice. SLAMF7+CD8+ T subsets produced more GZMB, IFN-γ, TNF-α and IL-2 than SLAMF7-CD8+ T subsets. Dexamethasone treatment ameliorated pancreatic inflammatory and fibrosis of AIP. Dexamethasone could downregulate SLAMF7+CD8+ T cells and reduce GZMB, IFN-γ and TNF-α levels both in vitro and in vivo. CONCLUSIONS: Increased SLAMF7+CD8+ T cells exhibit enhanced cytotoxicity and cytokines secretion capacity, which may be involved in the pathogenesis of AIP.


Assuntos
Doenças Autoimunes , Pancreatite Autoimune , Camundongos , Animais , Linfócitos T CD8-Positivos , Interleucina-2/efeitos adversos , Fator de Necrose Tumoral alfa , Doenças Autoimunes/patologia , Poli I-C/efeitos adversos , Dexametasona/efeitos adversos , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo
6.
Neurochem Res ; 48(12): 3485-3511, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37578655

RESUMO

Xanthones are natural secondary metabolites that possess great potential as neuroprotective agents due to their prominent biological effects on Alzheimer's disease (AD). However, their underlying mechanisms in AD remain unclear. This study aimed to systematically review the effects and mechanisms of xanthones in cell culture and animal studies, gaining a better understanding of their roles in AD. A comprehensive literature search was conducted in the Medline and Scopus databases using specific keywords to identify relevant articles published up to June 2023. After removing duplicates, all articles were imported into the Rayyan software. The article titles were screened based on predefined inclusion and exclusion criteria. Relevant full-text articles were assessed for biases using the OHAT tool. The results were presented in tables. Xanthones have shown various pharmacological effects towards AD from the 21 preclinical studies included. Cell culture studies demonstrated the anti-cholinesterase activity of xanthones, which protects against the loss of acetylcholine. Xanthones exhibited neuroprotective effects by promoting cell viability, reducing the accumulation of ß-amyloid and tau aggregation. The administration of xanthones in animal models resulted in a reduction in neuronal inflammation by decreasing microglial and astrocyte burden. In terms of molecular mechanisms, xanthones prevented neuroinflammation through the modulation of signaling pathways, including TLR4/TAK1/NF-κB and MAPK pathways. Mechanisms such as activation of caspase-3 and -9 and suppression of endoplasmic reticulum stress were also reported. Despite the various neuroprotective effects associated with xanthones, there are limited studies reported on their underlying mechanisms in AD. Further studies are warranted to fully understand their potential roles in AD.


Assuntos
Doença de Alzheimer , Fármacos Neuroprotetores , Xantonas , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Antioxidantes/farmacologia , Fármacos Neuroprotetores/farmacologia , Xantonas/farmacologia
7.
Metab Brain Dis ; 38(3): 1097-1113, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36648699

RESUMO

Delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) is one of the most common complications following carbon monoxide intoxication. Long noncoding RNAs (lncRNAs) exert critical functions in numerous neurological disorders. We intended to investigate the role of CRNDE in DEACMP. The DEACMP model in rats and the oxygen-glucose deprivation/reoxygenation (OGD/R) model in PC-12 cells were established. Brain and cell injuries were assessed with H&E staining, Nissl staining, TUNEL and CCK8 assays, respectively. Related proteins and RNAs were quantified with western blot and qRT-PCR. The N6-methyladenosine (m6A) level was determined using MeRIP-qPCR and immunofluorescence. Loss and gain function studies were performed to investigate the biological function of CRNDE. The potential mechanisms between each factor were explored using RNA immunoprecipitation, RNA-pull down and co-immunoprecipitation. CRNDE was increased in the hippocampal tissues of DEACMP rats and in OGD/R-treated PC-12 cells, which was positively correlated to m6A modification. Knockdown of CRNDE reduced cell damage and elevated UCHL5 and SMO expressions in OGD/R-treated PC-12 cells. hnRNPA1 was upregulated in DEACMP. In addition, inhibiting hnRNPA1 prevented apoptosis in PC-12 cells subjected to OGD/R. hnRNPA1 bound to CRNDE and remained in the nucleus, which inhibited UCHL5 expression through the formation of CRNDE-hnRNPA1-mRNA complex. UCHL5 could inhibit SMO ubiquitination and suppress PC-12 cell apoptosis during OGD/R. CRNDE silencing blocked brain injury in DEACMP, while knocking down UCHL5 reversed these effects. CRNDE interacted with hnRNPA1 to facilitate DEACMP via inhibition of UCHL5-mediated SMO deubiquitination. CRNDE might be a latent therapeutic target for treating DEACMP.


Assuntos
Encefalopatias , Intoxicação por Monóxido de Carbono , RNA Longo não Codificante , Ratos , Animais , Intoxicação por Monóxido de Carbono/complicações , RNA Longo não Codificante/genética , Oxigênio , Encefalopatias/complicações
8.
Arch Gynecol Obstet ; 308(2): 351-362, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-35947146

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of high-intensity focused ultrasound (HIFU) combined with the levonorgestrel intrauterine system (LNG-IUS) for adenomyosis. METHODS: We searched PubMed, Embase, Cochrane Library, Web of Science, CNKI, SinoMed, Wanfang, and VIP databases from their inception to Nov 20, 2021 for relevant articles that compared HIFU combined with LNG-IUS vs. HIFU alone in patients with adenomyosis. RevMan5.4 software was used for the data analysis. The primary outcome was changes in volume of the uterine. Secondary outcomes included visual analog scale (VAS) scores for dysmenorrhea, serum CA125 level, recurrence rate, changes in volume of the adenomyotic lesion, menstrual volume scores, and adverse reactions. Data synthesis was conducted using a random-effects model with significant heterogeneity (I2 > 50%), and using a fixed-effects model otherwise. This study is registered on the PROSPERO platform (CRD42021295214). RESULTS: The final analysis included 13 studies, with a total of 1861 patients. Results of analysis revealed that there was no significant difference in uterine volume reduction between the HIFU control group and the HIFU/LNG-IUS group at 3 months after procedure (MD:30.63). Compared with the HIFU control group, the HIFU/LNG-IUS group had more pronounced reduction in uterine volume at 6 (MD:29.04) and 12 months (MD:22.10) after procedure. The HIFU/LNG-IUS group has lower VAS scores for dysmenorrhea than the HIFU control group at 3 (MD:1.68), 6 (MD:1.69), and 12 months (MD:1.30) after procedure. Serum CA125 level in the HIFU/LNG-IUS group decreased more significantly than the HIFU control group at 6 (MD:18.34) and 12 months (MD:18.49) after procedure. The recurrence rate in the HIFU/LNG-IUS group was lower than that in the HIFU control group (RR:0.20). CONCLUSIONS: Compared to HIFU control group, HIFU/LNG-IUS group for the management of adenomyosis had more advantages in alleviating symptoms and decreasing the volumes of the uterine and adenomyotic lesions. However, since the number of the included studies was too small and some of them were not RCT, this conclusion needs to be referenced with caution.


Assuntos
Adenomiose , Dispositivos Intrauterinos Medicados , Feminino , Humanos , Levanogestrel/uso terapêutico , Adenomiose/cirurgia , Adenomiose/patologia , Dismenorreia/terapia , Útero/patologia , Menstruação
9.
Molecules ; 28(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36838552

RESUMO

Two unusual polyketide-sesquiterpene metabolites, craterodoratins T (1) and U (2), along with the known compound craterellin A (3), were isolated from the higher fungus Craterellus odoratus. The structures of isolated compounds were characterized based on nuclear magnetic resonance (NMR) and mass spectrum (MS) spectroscopic analysis, while the absolute configuration of the compounds was determined by theoretical NMR and electronic circular dichroism (ECD) calculations. Compound 1 possessed a rare structure with two aromatic groups. Compounds 1 and 3 showed immunosuppressive activity with IC50 values ranging from 5.516 to 19.953 µM.


Assuntos
Basidiomycota , Estrutura Molecular , Basidiomycota/química , Fungos , Espectroscopia de Ressonância Magnética/métodos , Dicroísmo Circular , Imunossupressores
10.
J Am Chem Soc ; 144(4): 1622-1633, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35060699

RESUMO

Naturally occurring hydrazones are rare despite the ubiquitous usage of synthetic hydrazones in the preparation of organic compounds and functional materials. In this study, we discovered a family of novel microbial metabolites (tasikamides) that share a unique cyclic pentapeptide scaffold. Surprisingly, tasikamides A-C (1-3) contain a hydrazone group (C═N─N) that joins the cyclic peptide scaffold to an alkyl 5-hydroxylanthranilate (AHA) moiety. We discovered that the biosynthesis of 1-3 requires two discrete gene clusters, with one encoding a nonribosomal peptide synthetase (NRPS) pathway for assembling the cyclic peptide scaffold and another encoding the AHA-synthesizing pathway. The AHA gene cluster encodes three ancillary enzymes that catalyze the diazotization of AHA to yield an aryl diazonium species (diazo-AHA). The electrophilic diazo-AHA undergoes nonenzymatic Japp-Klingemann coupling with a ß-keto aldehyde-containing cyclic peptide precursor to furnish the hydrazone group and yield 1-3. The studies together unraveled a novel mechanism whereby specialized metabolites are formed by the coupling of two biosynthetic pathways via an unprecedented in vivo Japp-Klingemann reaction. The findings raise the prospect of exploiting the arylamine-diazotizing enzymes (AAD) for the in vivo synthesis of aryl compounds and modification of biological macromolecules.


Assuntos
Compostos de Diazônio/química , Hidrazonas/química , Oligopeptídeos/biossíntese , Vias Biossintéticas/genética , Hidrazonas/síntese química , Família Multigênica , Oligopeptídeos/química , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Peptídeos Cíclicos/biossíntese , Peptídeos Cíclicos/química , Streptomyces/metabolismo
11.
Mol Med ; 28(1): 41, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35421923

RESUMO

BACKGROUND: The mechanisms of Gastric cancer (GC) initiation and progression are complicated, at least partly owing to the dynamic changes of gene regulation during carcinogenesis. Thus, investigations on the changes in regulatory networks can improve the understanding of cancer development and provide novel insights into the molecular mechanisms of cancer. METHODS: Differential co-expression analysis (DCEA), differential gene regulation network (GRN) modeling and differential regulation analysis (DRA) were integrated to detect differential transcriptional regulation events between gastric normal mucosa and cancer samples based on GSE54129 dataset. Cytological experiments and IHC staining assays were used to validate the dynamic changes of CREB1 regulated targets in different stages. RESULTS: A total of 1955 differentially regulated genes (DRGs) were identified and prioritized in a quantitative way. Among the top 1% DRGs, 14 out of 19 genes have been reported to be GC relevant. The four transcription factors (TFs) among the top 1% DRGs, including CREB1, BPTF, GATA6 and CEBPA, were regarded as crucial TFs relevant to GC progression. The differentially regulated links (DRLs) around the four crucial TFs were then prioritized to generate testable hypotheses on the differential regulation mechanisms of gastric carcinogenesis. To validate the dynamic alterations of gene regulation patterns of crucial TFs during GC progression, we took CREB1 as an example to screen its differentially regulated targets by using cytological and IHC staining assays. Eventually, TCEAL2 and MBNL1 were proved to be differentially regulated by CREB1 during tumorigenesis of gastric cancer. CONCLUSIONS: By combining differential networking information and molecular cell experiments verification, testable hypotheses on the regulation mechanisms of GC around the core TFs and their top ranked DRLs were generated. Since TCEAL2 and MBNL1 have been reported to be potential therapeutic targets in SCLC and breast cancer respectively, their translation values in GC are worthy of further investigation.


Assuntos
Neoplasias Gástricas , Carcinogênese/genética , Transformação Celular Neoplásica/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Neoplasias Gástricas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Ann Surg ; 276(5): e483-e492, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32889872

RESUMO

OBJECTIVE: To investigate the association of graft steatosis with long-term outcome, and to elucidate the mechanism of steatotic graft injury in adult living donor liver transplantation. SUMMARY OF BACKGROUND DATA: The utilization of steatotic graft expands the donor pool for living donor liver transplantation (LDLT). However, it remains controversial due to its high morbidity and mortality. Elucidating the mechanism of steatotic graft injury is crucial to develop therapeutic strategies targeting at graft injury and to further expand the donor pool. METHODS: Five hundred thirty patients receiving LDLT were prospectively included for risk factor analysis and outcome comparison. Rat orthotopic liver transplantation, in vitro functional experiments and mouse hepatic ischemia/ reperfusion models were established to explore the mechanisms of steatotic graft injury. RESULTS: We identified that graft with >10% steatosis was an independent risk factor for long-term graft loss after LDLT (hazard ratio 2.652, P = 0.001), and was associated with shorter cancer recurrence-free survival and acute phase liver injury. Steatotic graft displayed distinct mitochondrial dysfunction, including membrane, calcium, and energy homeostasis dysregulation. Specifically, the mitochondrial biogenesis was remarkably downregulated in steatotic graft. Inhibition of AMPK-PGC1α axis impaired mitochondrial biogenesis and was lethal to fatty hepatocyte in vitro , whereas reactivation of AMPK promoted PGC1α-mediated mitochondrial biogenesis and attenuated liver injury via restoring mitochondrial function in animal model. Conclusions: We provided a new mechanism that compromised AMPK-PGC1α axis exacerbated steatotic graft injury in LDLT by dysregulating mitochondrial homeostasis through impairment of biogenesis.


Assuntos
Fígado Gorduroso , Transplante de Fígado , Traumatismo por Reperfusão , Proteínas Quinases Ativadas por AMP , Animais , Cálcio , Modelos Animais de Doenças , Homeostase , Humanos , Fígado , Doadores Vivos , Camundongos , Mitocôndrias , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Ratos
13.
Appl Environ Microbiol ; 88(23): e0120822, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36350133

RESUMO

Angucyclines are a family of structurally diverse, aromatic polyketides with some members that exhibit potent bioactivity. Angucyclines have also attracted considerable attention due to the intriguing biosynthetic origins that underlie their structural complexity and diversity. Balmoralmycin (compound 1) represents a unique group of angucyclines that contain an angular benz[α]anthracene tetracyclic system, a characteristic C-glycosidic bond-linked deoxy-sugar (d-olivose), and an unsaturated fatty acid chain. In this study, we identified a Streptomyces strain that produces balmoralmycin and seven biosynthetically related coproducts (compounds 2-8). Four of the coproducts (compounds 5-8) are novel compounds that feature a highly oxygenated or fragmented lactone ring, and three of them (compounds 3-5) exhibited cytotoxicity against the human pancreatic cancer cell line MIA PaCa-2 with IC50 values ranging from 0.9 to 1.2 µg/mL. Genome sequencing and CRISPR/dCas9-assisted gene knockdown led to the identification of the ~43 kb balmoralmycin biosynthetic gene cluster (bal BGC). The bal BGC encodes a type II polyketide synthase (PKS) system for assembling the angucycline aglycone, six enzymes for generating the deoxysugar d-olivose, and a hybrid type II/III PKS system for synthesizing the 2,4-decadienoic acid chain. Based on the genetic and chemical information, we propose a mechanism for the biosynthesis of balmoralmycin and the shunt products. The chemical and genetic studies yielded insights into the biosynthetic origin of the structural diversity of angucyclines. IMPORTANCE Angucyclines are structurally diverse aromatic polyketides that have attracted considerable attention due to their potent bioactivity and intriguing biosynthetic origin. Balmoralmycin is a representative of a small family of angucyclines with unique structural features and an unknown biosynthetic origin. We report a newly isolated Streptomyces strain that produces balmoralmycin in a high fermentation titer as well as several structurally related shunt products. Based on the chemical and genetic information, a biosynthetic pathway that involves a type II polyketide synthase (PKS) system, cyclases/aromatases, oxidoreductases, and other ancillary enzymes was established. The elucidation of the balmoralmycin pathway enriches our understanding of how structural diversity is generated in angucyclines and opens the door for the production of balmoralmycin derivatives via pathway engineering.


Assuntos
Policetídeos , Streptomyces , Humanos , Vias Biossintéticas/genética , Família Multigênica , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Policetídeos/metabolismo , Streptomyces/metabolismo , Linhagem Celular Tumoral
14.
BMC Cancer ; 22(1): 166, 2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35151264

RESUMO

BACKGROUND: Synovial sarcoma (SS) is a type of soft tissue sarcoma (STS) of undetermined tissue origin, which is characterized by the recurrent pathognomonic chromosomal translocation t (X;18)(p11.2; q11.2). Studies have shown that SS is a malignant tumor originating from cancer stem cells or pluripotent mesenchymal stem cells and may be related to fusion genes. In addition, some studies have indicated that the induction of epithelial-mesenchymal transition (EMT) via the TGF-ß1/Smad signaling pathway leads to SS metastasis. METHODS: We analyzed the effects of SYT-SSX1 on the stemness of SS cells via TGF-ß1/Smad signaling in vitro. The SYT-SSX1 fusion gene high expression cell was constructed by lentiviral stable transfer technology. SYT-SSX1 and SW982 cells were cultured and tested for sphere-forming ability. The transwell migration assay and flow cytometry were used to assess the migration ability of the sphere cells as well as the expression of CSC-related markers. We treated SYT-SSX1 cells with rhTGF-ß1 (a recombinant agent of the TGF-ß1 signaling pathway) and SB431542 and observed morphological changes. A CCK-8 experiment and a western blot (WB) experiment were conducted to detect the expression of TGF-ß1 signaling pathway- and EMT-related proteins after treatment. The SYT-SSX1 cells were then cultured and their ability to form spheres was tested. Flow cytometry, WB, and quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect the expression of CSC surface markers on SYT-SSX1 sphere cells. RESULTS: It was found that SYT-SSX1 has stronger sphere-forming ability, migration ability, and higher expression of CSC-related molecules than SW982 cells. Through treating SYT-SSX1 and SW982 cells with rhTGF-ß1 and SB431542, we found that TGF-ß1 enhanced the proliferation of cells, induced EMT, and that TGF-ß1 enhanced the characteristics of tumor stem cells. CONCLUSIONS: Our results suggest that SYT-SSX1 enhances invasiveness and maintains stemness in SS cells via TGF-ß1/Smad signaling. These findings reveal an effective way to potentially improve the prognosis of patients with SS by eliminating the characteristics of cancer stem cells (CSCs) during treatment.


Assuntos
Proteínas de Fusão Oncogênica/metabolismo , Sarcoma Sinovial/genética , Sarcoma/genética , Transdução de Sinais/genética , Neoplasias de Tecidos Moles/genética , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Humanos , Invasividade Neoplásica/genética , Prognóstico , Sarcoma/patologia , Sarcoma Sinovial/patologia , Proteínas Smad/metabolismo , Neoplasias de Tecidos Moles/patologia , Fator de Crescimento Transformador beta1/metabolismo , Translocação Genética/genética
15.
Virol J ; 19(1): 81, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35570279

RESUMO

BACKGROUND: Human rhinovirus C (HRV-C) accounts for a large proportion of HRV-related illnesses, but the immune response to HRV-C infection has not been elucidated. Our objective was to assess the effect of HRV-C on cytokine secretion in human bronchial epithelial (HBE) cells grown at air-liquid interface (ALI) and compare it with that of respiratory syncytial virus (RSV). METHODS: HBE cells were differentiated at ALI culture and the full-length cDNA clones of HRV-C651 and HRV-C15, clinical isolates of HRV-C79 and HRV-C101, and two RSV isolates were inoculated in the HBE cells. The effect of HRV-C on cytokine secretion was assessed and compared with that of RSV. RESULTS: HRV-Cs infect and propagate in fully differentiated HBE cells and significantly increase the secretion of IFN-λ1, CCL5, IP10, IL-6, IL-8, and MCP-1. The virus loads positively correlated with the levels of the cytokines. HRV-C induced lower secretion of CCL5 (P = 0.048), IL-6 (P = 0.016), MCP-1 (P = 0.008), and IL-8 (P = 0.032), and similar secretion of IP10 (P = 0.214) and IFN-λ1 (P = 0.214) when compared with RSV. CONCLUSION: HBE ALI culture system supported HRV-C infection and propagation and HRV-C induced relatively weaker cytokine expression than RSV.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Quimiocina CXCL10 , Citocinas , Enterovirus , Células Epiteliais , Humanos , Imunidade , Interleucina-6 , Interleucina-8 , Rhinovirus
16.
Eur Radiol ; 32(3): 2110-2119, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34751794

RESUMO

OBJECTIVES: To determine whether contrast-enhanced ultrasonography (CEUS) can be used for selecting lesions and assessing the ablative effects of MRgFUS ablation on uterus fibroids, compared with MR imaging. METHODS: This retrospective study was approved by the institutional review board of our hospital. From April 2018 to November 2019, a total of 44 symptomatic fibroids in 38 patients who underwent MRgFUS ablation were included. The association between pre-ablation characteristics on CEUS/MR imaging and the non-perfusion volume (NPV) after ablation was analyzed using multivariable linear regression analysis. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve values was compared between the CEUS and MR imaging regression models. NPV after ablation was compared between CEUS and enhanced MR imaging. RESULTS: On CEUS, entangled branch vessels, fast-in, and fast-out patterns were significantly associated with NPV, with an AUC of 0.95 (95% CI; 0.88, 1.00). On MR imaging, hyper-intensity on T2-weighted images (T2WI), hyper-intense ring-like signal on T2WI images, and hyper-enhancement on contrast-enhanced T1WI images were correlated with NPV, with an AUC of 0.86 (95% CI; 0.70, 1.00). After ablation, no differences in NPV were noted between contrast-enhanced T1WI (84.13 ± 75.42 cm3) and CEUS (80.22 ± 76.49 cm3). CONCLUSIONS: Some pre-ablation characteristics of uterine fibroids on CEUS were associated with NPV after MRgFUS. CEUS may contribute to the evaluation of ablative outcomes and patient selection, similar to MR imaging. KEY POINTS: • Contrast-enhanced ultrasonography (CEUS) is effective for selecting the appropriate uterine fibroids before MR-guided focused ultrasound (MRgFUS) ablation and evaluating non-perfusion volumes (NPV) after ablation, as a potential alternative to MR imaging. • Before ablation, entangled branch vessels, fast-in, and fast-out patterns on CEUS were significantly associated with NPV after MRgFUS. • No significant differences in NPV were detected between contrast-enhanced T1WI and CEUS after ablation.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma , Neoplasias Uterinas , Feminino , Humanos , Leiomioma/diagnóstico por imagem , Leiomioma/cirurgia , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/cirurgia , Útero
17.
Clin Transplant ; 36(10): e14635, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35291044

RESUMO

BACKGROUND: Prompt identification of early allograft dysfunction (EAD) is critical to reduce morbidity and mortality in liver transplant (LT) recipients. OBJECTIVES: Evaluate the evidence supporting biomarkers that can provide diagnostic and predictive value for EAD. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach was derived from an international expert panel. Studies that investigated biomarkers or models for predicting EAD in adult LT recipients were included for in-depth evaluation and meta-analysis. Olthoff's criteria were used as the standard reference for the diagnostic accuracy evaluation. PROSPERO ID: CRD42021293838 RESULTS: Ten studies were included for the systematic review. Lactate, lactate clearance, uric acid, Factor V, HMGB-1, CRP to ALB ratio, phosphocholine, total cholesterol, and metabolomic predictive model were identified as potential early EAD predictive biomarkers. The sensitivity ranged between .39 and .92, while the specificity ranged from .63 to .90. Elevated lactate level was most indicative of EAD after adult LT (pooled diagnostic odds ratio of 7.15 (95%CI: 2.38-21.46)). The quality of evidence (QOE) for lactate as indicator was moderate according to the GRADE approach, whereas the QOE for other biomarkers was very low to low likely as consequence of study design characteristics such as single study, small sample size, and large ranges of sensitivity or specificity. CONCLUSIONS: Lactate is an early indicator to predict EAD after LT (Quality of Evidence: Moderate | Grade of Recommendation: Strong). Further multicenter studies and the use of machine perfusion setting should be implemented for validation.


Assuntos
Transplante de Fígado , Adulto , Humanos , Transplante de Fígado/efeitos adversos , Aloenxertos , Fatores de Risco , Transplante Homólogo , Biomarcadores , Ácido Láctico
18.
Org Biomol Chem ; 20(32): 6293-6313, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35838160

RESUMO

As one of the most important structural units in pharmaceuticals and medicinal chemistry, quinazolinone and its derivatives exhibit a wide range of biological and pharmacological activities, including anti-inflammatory, antitubercular, antiviral, and anticancer activities, etc. In particular, 2,3-fused quinazolinones have attracted much attention because the rings fused to the 2,3-positions of quinazolinones improve their rigidity and planarity. Their synthetic strategies have made great advances in recent years. Therefore, this review focuses on novel strategies for the synthesis of 2,3-fused quinazolinone derivatives from 2017 to 2022, such as the difunctionalization of alkenes, the ring-opening of easily available small rings, dehydrogenative cross-coupling reactions, transition-metal catalyzed cyclizations, cycloadditions, and other cascade reactions.


Assuntos
Química Farmacêutica , Quinazolinonas , Reação de Cicloadição , Quinazolinonas/química
19.
Pathobiology ; 89(3): 135-145, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34872094

RESUMO

OBJECTIVE: Sepsis-associated encephalopathy (SAE) is a severe and common complication of sepsis and can induce cognitive dysfunction and apoptosis of neurons and neuroinflammation. Emodin has been confirmed to have anti-inflammatory effects. Thus, we sought to investigate the role of Emodin in SAE. METHODS: The cecal ligation and puncture (CLP) method was used for the establishment of SAE in mice model. For treatment of Emodin, intraperitoneal injection of 20 mg/kg Emodin was performed before the surgery. The Morris water maze and open field tests were carried for measurement of cognitive dysfunction. Hematoxylin and eosin staining was for histological analysis of hippocampus. Cell apoptosis of hippocampus neurons was measured by TUNEL staining. Pro-inflammatory and anti-inflammatory cytokines in hippocampus tissue homogenate were evaluated by ELISA. BDNF/TrkB signaling-related proteins (TrkB, p-TrkB, and BDNF), autophagy-related proteins (LC3 II/I and Beclin-1), and apoptosis-related proteins (Bax, Bcl-2, and cleaved caspase-3) were detected by Western blotting. RESULTS: Emodin significantly inhibited apoptosis and induced autophagy in hippocampal neurons of CLP-treated mice. In addition, Emodin significantly ameliorated CLP-induced cognitive dysfunction and pathological injury in mice. Meanwhile, Emodin notably inhibited CLP-induced inflammatory responses in mice via upregulation of BDNF/TrkB signaling, while the effect of Emodin was partially reversed in the presence of K252a (BDNF/TrkB signaling inhibitor). CONCLUSION: Emodin significantly inhibited the progression of SAE via mediation of BDNF/TrkB signaling. Thus, Emodin might serve as a new agent for SAE treatment.


Assuntos
Emodina , Encefalopatia Associada a Sepse , Animais , Apoptose , Autofagia/fisiologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Emodina/metabolismo , Emodina/farmacologia , Hipocampo/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Receptor trkB/metabolismo , Encefalopatia Associada a Sepse/tratamento farmacológico , Encefalopatia Associada a Sepse/metabolismo
20.
Org Biomol Chem ; 20(10): 2069-2074, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35201247

RESUMO

A variety of functionalized spiroindolenine-3,3'-pyrrolo[2,1-b]quinazolinones were prepared in good to excellent yields through a gold(I)-catalyzed dearomative cyclization of N-alkynyl quinazolinone-tethered C2-substituted indoles. This reaction features a broad substrate scope, good functional group tolerance, and easy gram-scale preparation and transformations. Furthermore, biological activity studies showed that most of the obtained spiroindolenine-3,3'-pyrrolo[2,1-b]quinazolinone scaffolds showed potential as good anti-inflammatory agents.

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