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1.
Nat Immunol ; 13(6): 560-8, 2012 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-22561606

RESUMO

Signaling via the T cell antigen receptor (TCR) during the CD4(+)CD8(+) double-positive developmental stage determines thymocyte selection and lineage commitment. Here we describe a previously uncharacterized T cell-expressed protein, Tespa1, with critical functions during the positive selection of thymocytes. Tespa1(-/-) mice had fewer mature thymic CD4(+) and CD8(+) T cells, which reflected impaired thymocyte development. Tespa1 associated with the TCR signaling components PLC-γ1 and Grb2, and Tespa1 deficiency resulted in attenuated TCR signaling, as reflected by defective activation of the Erk-AP-1 and Ca(2+)-NFAT pathways. Our findings demonstrate that Tespa1 is a component of the TCR signalosome and is essential for T cell selection and maturation through the regulation of TCR signaling during T cell development.


Assuntos
Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Timo/imunologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular/imunologia , Clonagem Molecular , Proteína Adaptadora GRB2/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Dados de Sequência Molecular , Fosfolipase C gama/imunologia , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Transdução de Sinais/imunologia , Timo/citologia
2.
Chem Biodivers ; 20(9): e202301032, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37561609

RESUMO

The genus of Ainsliaea embraces approximately 70 recognized species, many of which have been used to treat various diseases in folklore medicines. As the main metabolites of Ainsliaea plants, Ainsliaea sesquiterpenoids have drawn considerable attention in related scientific communities due to their intriguing structures and a variety of bioactivities. In this review, we intend to provide a full-aspect coverage of sesquiterpenoids reported from the genus of Ainsliaea, including 145 monomeric sesquiterpenoids and 30 oligomeric ones. Multiple aspects will be summarized, including their classification, distributions, structures, bioactivities, and biomimetic syntheses. In addition, their possible biosynthetic pathway will be discussed in detail.


Assuntos
Asteraceae , Sesquiterpenos , Estrutura Molecular , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Asteraceae/química , Extratos Vegetais/química
3.
J Wound Care ; 32(Sup6a): lxxxvii-xcvi, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37306381

RESUMO

CONCLUSION: Upon wound formation, the wound temperature rises in the first 3-4 days until reaching its peak. It then falls at about one week after wound formation. In the second week after wound formation, the wound temperature decreases steadily to the baseline indicating a good wound condition and progression towards healing. While a continuous high temperature is often a sign of excessive inflammation or infection, which indicates urgent need of intervention and treatment.


Assuntos
Inflamação , Cicatrização , Humanos , Temperatura
4.
Angew Chem Int Ed Engl ; 62(5): e202214814, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36461785

RESUMO

Efficient biosynthesis of microbial bioactive natural products (NPs) is beneficial for the survival of producers, while self-protection is necessary to avoid self-harm resulting from over-accumulation of NPs. The underlying mechanisms for the effective but tolerable production of bioactive NPs are not well understood. Herein, in the biosynthesis of two fungal polyketide mycotoxins aurovertin E (1) and asteltoxin, we show that the cyclases in the gene clusters promote the release of the polyketide backbone, and reveal that a signal peptide is crucial for their subcellular localization and full activity. Meanwhile, the fungus adopts enzymatic acetylation as the major detoxification pathway of 1. If intermediates are over-produced, the non-enzymatic shunt pathways work as salvage pathways to avoid excessive accumulation of the toxic metabolites for self-protection. These findings provided new insight into the interplay of efficient backbone release and multiple detoxification strategies for the production of fungal bioactive NPs.


Assuntos
Micotoxinas , Policetídeos , Policetídeos/metabolismo , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Processamento de Proteína Pós-Traducional , Família Multigênica
5.
Bioorg Chem ; 119: 105573, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34952245

RESUMO

Tetrodecadazinone (1), a novel tetrodecamycin-pyridazinone hybrid possessing a new 1,2-dimethyl-1-(2-methylnonyl)decahydronaphthalene skeleton, and 4-hydroxydihydrotetrodecamycin (2) were separated from a culture of Streptomyces sp. HU051, together with a known compound, dihydrotetrodecamycin (3). Diverse spectroscopic approaches were applied to assign the structures of 1-3, and the structure of 1 was further confirmed by single crystal X-ray diffraction analysis. Compound 1 is the first example of a pyridazinone-containing natural product. Biosynthetically, 1 is proposed to be derived from a Michael addition reaction of a PKS-derived tetrodecamycin and a piperazic-acid-derived pyridazinone. Biological evaluation revealed 1 could reduce the expressions of extracellular matrix proteins (fibronectin and collagen I) and α-smooth muscle actin (α-SMA) in transforming growth factor-ß (TGF-ß1)-activated LX-2 cells. Preliminary mechanism study showed 1 exerted its anti-liver fibrosis effect by regulating TGF-ß1/Smad2/3 signaling pathway.


Assuntos
Antibacterianos/farmacologia , Cirrose Hepática/tratamento farmacológico , Streptomyces/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/microbiologia , Testes de Sensibilidade Microbiana , Conformação Molecular , Transdução de Sinais/efeitos dos fármacos , Proteína Smad2/antagonistas & inibidores , Proteína Smad2/metabolismo , Proteína Smad3/antagonistas & inibidores , Proteína Smad3/metabolismo , Relação Estrutura-Atividade , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Fator de Crescimento Transformador beta1/metabolismo
6.
Graefes Arch Clin Exp Ophthalmol ; 260(7): 2369-2377, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35147748

RESUMO

PURPOSE: To investigate the pathogenic features of the polypoidal lesions from the specimens of polypoidal choroidal vasculopathy extracted from human subjects. METHODS: Seven specimens of polypoidal lesions extracted from five eyes of six patients (mean age, 60.16 ± 10.41 years) of polypoidal choroidal vasculopathy were examined. The polypoidal lesions were obtained by surgical excision. Thereafter, a histopathological analysis of the specimens was performed. RESULTS: The polypoidal lesions were oval nodules located underneath the retinal pigment epithelium. A pathological study of the lesions revealed that Bruch's membrane schisis was observed in all specimens and they were all located in the Bruch's membrane. The Bruch's membrane schisis and serosanguineous materials constituted the main structure of the lesions in five of the seven specimens, with small vessels being observed in two specimens. One specimen was composed of two polypoidal lesions of different characteristics, and one specimen had a neovessel membrane complex with several polypoidal lesions. Inflammatory cells and blood vessels were observed in the polypoidal lesion of the specimen with neovessel membrane complex. CONCLUSION: Polypoidal lesions of polypoidal choroidal vasculopathy are abnormalities of the Bruch's membrane. The lesions are characterized by the Bruch's membrane schisis, which is filled with serosanguineous materials. The lesions are progressive and may contain inflammatory cells and blood vessels.


Assuntos
Doenças da Coroide , Oftalmopatias , Degeneração Macular , Doenças Vasculares , Idoso , Lâmina Basilar da Corioide/patologia , Corioide/patologia , Doenças da Coroide/diagnóstico , Angiofluoresceinografia , Humanos , Degeneração Macular/patologia , Pessoa de Meia-Idade
7.
BMC Ophthalmol ; 22(1): 307, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842598

RESUMO

BACKGROUND: To establish and verify the accuracy and reliability of a sulcus-to-sulcus diameter (STS) prediction model. METHODS: In this retrospective study, the prediction formula was established with the data from 1466 eyes from 733 subjects from July 2020 to April 2021 and verified with the data from 278 eyes from 139 subjects between May 2021 and June 2021. Each subject was measured with a Pentacam, IOLMaster 700, OPD-Scan III, and ultrasound biomicroscope. The prediction formulas were established with multiple linear regression, and intergroup correlation coefficients (ICCs) and Bland-Altman tests were used to assess the agreement between the predicted and actual STS (actual STS was measured by UBM). RESULTS: The explanatory variables relevant to the horizontal STS (STSH) were the Pentacam white-to-white diameter (WTWP; standardized partial regression coefficient [ß] = 0.330; p < 0.001), the flat K value (ß = -0.211; p < 0.001), and the anterior corneal diameter (ACD) (ß = 0.178; p < 0.001). The corresponding multiple regression equation was : STSH (mm) = 8.061 + 0.510 × WTWP - 0.090 × Flat K value + 0.430 × ACD. The explanatory variables relevant to the vertical STS (STSV) were the WTWP (ß = 0.435; p < 0.001), the steep K value (ß = -0.271; p < 0.001), and the ACD (ß = 0.187; p < 0.001). The corresponding multiple regression equation was : STSV (mm) = 8.540 + 0.492 × WTWP - 0.075 × Steep K value + 0.329 × ACD. The bias of the predicted to the actual STSH was - 0.021, with 95% limits of agreement (95% LoA) from - 0.499 to 0.457. The bias of the predicted to the actual STSV was 0.057, with 95% LoA from - 0.462 to 0.575. The ICC was 0.883 between the predicted and actual STSH and 0.859 between the predicted and actual STSV. CONCLUSIONS: The Pentacam-measured WTW, the K value and the ACD are important for predicting the STS diameter. The prediction model has good accuracy and reliability. TRIAL REGISTRATION: Not applicable.


Assuntos
Câmara Anterior , Miopia , Câmara Anterior/diagnóstico por imagem , Biometria , Córnea/diagnóstico por imagem , Humanos , Microscopia Acústica , Miopia/diagnóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos
8.
BMC Ophthalmol ; 22(1): 463, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36451125

RESUMO

BACKGROUND: To verify the accuracy and stability of the prediction formula based on the ciliary sulcus diameter and lens thickness and to analyse factors influencing the prediction results. METHODS: In total, 925 eyes from 506 subjects were enrolled in this prospective study between July 1, 2020, and June 30, 2021. Subjects were divided into four seasons, each spanning three months. The target vault was set to be between 300 µm and 700 µm according the prediction formula. The actual vault was measured one month postoperatively. The Bland-Altman test, 95% confidence intervals (95% CI) and 95% limits of agreement (95% LoA) were used to evaluate the agreement between the predicted vault and the actual vault. Eyes with absolute prediction errors greater than 300 µm were further analysed. RESULTS: The mean predicted vaults for the four seasons were 503 ± 99, 494 ± 96, 481 ± 92 and 502 ± 93 µm, while the mean actual vaults were 531 ± 189, 491 ± 179, 464 ± 179 and 529 ± 162 µm, respectively. The predicted and actual vaults of the overall subjects were 493 ± 95 and 500 ± 180 µm, respectively. Of the 925 eyes, 861 eyes (93.08%), 42 eyes (4.54%), and 22 eyes (2.38%) showed a normal vault, high vault, and low vault, respectively. Bland-Altman plots showed that the mean difference between the actual vault and predicted vault overall (± 95% LoA) was 6.43 ± 176.2 µm (-339 to 352 µm). Three UBM features may lead to large prediction errors (more than 300 µm): wide iris-ciliary angle (ICA), iris concavity and anteriorly positioned ciliary body. CONCLUSIONS: This study demonstrated the accuracy and stability of the prediction formula through the validation of a large sample size and a long time span. Wide ICA, iris concavity and anteriorly positioned ciliary body may have an effect on vault.


Assuntos
Corpo Ciliar , Humanos , Estudos Prospectivos , Estações do Ano
9.
Chem Biodivers ; 19(11): e202200660, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36156394

RESUMO

A serial jatrophane-type diterpenoids, comprised with three undescribed compounds kanesulones C-E (1-3) and four known ones (4-7), were obtained from the roots of Euphorbia kansui. The structures of compounds 1-3 were elucidated by detailed interpretation of their spectroscopic data, especially 2D-NMR and HR-ESI-MS, the absolute configuration of 1 was revealed by single crystal X-ray diffraction. These isolates were assayed for their multidrug resistance reversing activities on human breast adenocarcinoma cell line MCF-7/ADR. Compound 1 possessed potential as low toxic MDR modulator that could promote the efficacy of anticancer drug adriamycin ca. 85-fold at 5 µM, as 12 times stronger than the positive drug verapamil.


Assuntos
Diterpenos , Euphorbia , Humanos , Euphorbia/química , Estrutura Molecular , Diterpenos/farmacologia , Diterpenos/química , Resistência a Múltiplos Medicamentos
10.
Blood ; 134(19): 1670-1682, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31533918

RESUMO

Myeloid-derived suppressor cells (MDSCs) can subdue inflammation. In mice with acute graft-versus-host disease (GVHD), donor MDSC infusion enhances survival that is only partial and transient because of MDSC inflammasome activation early posttransfer, resulting in differentiation and loss of suppressor function. Here we demonstrate that conditioning regimen-induced adenosine triphosphate (ATP) release is a primary driver of MDSC dysfunction through ATP receptor (P2x7R) engagement and NLR pyrin family domain 3 (NLRP3) inflammasome activation. P2x7R or NLRP3 knockout (KO) donor MDSCs provided significantly higher survival than wild-type (WT) MDSCs. Although in vivo pharmacologic targeting of NLRP3 or P2x7R promoted recipient survival, indicating in vivo biologic effects, no synergistic survival advantage was seen when combined with MDSCs. Because activated inflammasomes release mature interleukin-1ß (IL-1ß), we expected that IL-1ß KO donor MDSCs would be superior in subverting GVHD, but such MDSCs proved inferior relative to WT. IL-1ß release and IL-1 receptor expression was required for optimal MDSC function, and exogenous IL-1ß added to suppression assays that included MDSCs increased suppressor potency. These data indicate that prolonged systemic NLRP3 inflammasome inhibition and decreased IL-1ß could diminish survival in GVHD. However, loss of inflammasome activation and IL-1ß release restricted to MDSCs rather than systemic inhibition allowed non-MDSC IL-1ß signaling, improving survival. Extracellular ATP catalysis with peritransplant apyrase administered into the peritoneum, the ATP release site, synergized with WT MDSCs, as did regulatory T-cell infusion, which we showed reduced but did not eliminate MDSC inflammasome activation, as assessed with a novel inflammasome reporter strain. These findings will inform future clinical using MDSCs to decrease alloresponses in inflammatory environments.


Assuntos
Trifosfato de Adenosina/metabolismo , Doença Enxerto-Hospedeiro/imunologia , Inflamassomos/imunologia , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/transplante , Animais , Feminino , Camundongos , Camundongos Knockout
11.
BMC Ophthalmol ; 21(1): 199, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33957891

RESUMO

BACKGROUND: To describe the very early vault changes in the first month after Implantable Collamer Lens (ICL) implantation and to evaluate the effect of preoperative biometric factors on vault. METHODS: Eighty-three eyes from eighty-three subjects with complete data who met follow-up requirements were recruited in this retrospective study between May 2019 and March 2020. We quantitatively assessed the postoperative vault at 2 h, 1 day, 1 week, and 1 month following implantation. Associations between the postoperative vault and age, ICL size, spherical equivalent (SE), axial length (AL), central corneal thickness (CCT), flat keratometry (K), steep K, mean K, anterior chamber depth (ACD), crystalline lens thickness (LT), white-to-white (WTW) diameter obtained by three devices, horizontal and vertical sulcus-to-sulcus (STS) diameter, bright and dark pupil sizes (BPS and DPS) and DPS-BPS were investigated using Spearman's correlation analysis and stepwise multiple regression analysis. RESULTS: The mean vault values at 2 h, 1 day, 1 week, and 1 month after ICL implantation were 672.05 ± 30.72, 389.15 ± 28.33, 517.23 ± 30.76 and 530.12 ± 30.22 µm, respectively. Significant differences were found in the vault values at 2 h, 1 day and 1 week after the operation. The ICL size (ß = 0.942; p < 0.001), followed by horizontal STS (ß = -0.517; p < 0.001), crystalline LT (ß = -0.376; p < 0.001) and vertical STS (ß = -0.257; p = 0.017), significantly influenced the vault at 1 month after the operation. The multiple regression equation was expressed as follows: central vault (µm) = -1369.05 + 657.121 × ICL size- 287.408 × horizontal STS - 432.497 × crystalline LT - 137.33 × vertical STS (adjusted R2 = 0.643). CONCLUSIONS: After ICL implantation, the vault decreased and then increased, but it did not return to the vault value 2 h after surgery. The ICL size, horizontal and vertical STS and crystalline LT are key factors for predicting postoperative vaulting.


Assuntos
Miopia , Lentes Intraoculares Fácicas , Humanos , Implante de Lente Intraocular , Miopia/cirurgia , Estudos Retrospectivos , Acuidade Visual
12.
Nat Prod Rep ; 37(7): 999-1030, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32104815

RESUMO

Covering: July 2010 to August 2019. Previous review: Nat. Prod. Rep., 2011, 28, 594The review covers recent progress on the isolation, identification, bioactivity and biomimetic synthesis of natural dimeric sesquiterpenoids, along with a detailed discussion of the biogenesis of these metabolites. Structural revisions are included.


Assuntos
Produtos Biológicos/química , Sesquiterpenos/química , Dimerização , Estrutura Molecular
13.
Wound Repair Regen ; 28(3): 326-337, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31868976

RESUMO

Dressings are necessary during the process of wound healing. Since the early 1980s, several types of wound dressings have been produced, but they cannot always take into account some effects include antibacterial effect, wound healing promotion, and other properties. In this study, we would like to develop an effective dressing with the above properties, especially accelerating wound healing effect. A chitosan-calcium alginate dressing (CCAD) was developed by coating mixture of chitosan with high-low molecular weight on calcium alginate dressing (CAD). We investigated the structural characteristics of CCAD with Fourier-transform infrared spectroscopy (FTIR) and electron microscopy. The cytotoxicity and antibacterial property were evaluated in vitro using CCK-8 and inhibition zone method. Moisture retention was tested on the skin of Sprague-Dawley (SD) rats, and wound healing studies were performed on a full-thickness skin wound model in SD rats. CCAD showed good moisturizing and antibacterial properties with no cytotoxicity. CCAD could inhibit inflammation by decreasing IL-6, and it could also promote angiogenesis by increasing VEGF, resulting in better wound healing than CAD. CCAD is a better choice in wound care due to its antibacterial property, biocompatibility, moisture retention, healing promotion, and non-cytotoxicity characteristics.


Assuntos
Alginatos/ultraestrutura , Bandagens , Quitosana/uso terapêutico , Hemostáticos/uso terapêutico , Pele/lesões , Ferida Cirúrgica/terapia , Animais , Modelos Animais de Doenças , Masculino , Microscopia Eletrônica , Ratos , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Ferida Cirúrgica/patologia , Ferida Cirúrgica/fisiopatologia , Cicatrização
14.
J Nat Prod ; 83(5): 1641-1645, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32367724

RESUMO

Microeunicellols A (1) and B (2), two undescribed eunicellin diterpenoids, were isolated from the culture of a bacterial symbiont, Streptomyces albogriseolus SY67903. Their structures, including absolute configurations revealed by spectroscopic data and single-crystal X-ray diffraction analysis, are closely related with the diterpenoids from its host, a South China Sea gorgonian, Muricella sibogae. This is the first report of eunicellin diterpenoids, commonly coral-derived, from a bacterial symbiont of coral. The chemical metabolic relationship between the bacterium and its host is discussed. Biological evaluation revealed that compound 1 possessed cytotoxicities against several human cancer cell lines.


Assuntos
Diterpenos/farmacologia , Streptomyces/química , Terpenos/farmacologia , Animais , Antozoários/química , Linhagem Celular Tumoral , China , Diterpenos/química , Diterpenos/isolamento & purificação , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Terpenos/isolamento & purificação
15.
Acta Biochim Biophys Sin (Shanghai) ; 52(1): 91-96, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31833535

RESUMO

Distamycin (DST) is a well-characterized DNA minor groove binder with antivirus activity and antitumor potency. Two separate gene clusters (a 28-kb cluster and a 7-kb cluster) have recently been identified to coordinately encode the biosynthetic machinery of DST in Streptomyces netropsis. Here we report a gene cassette, which is linked to the aforementioned smaller dst gene cluster and plays an important role in the self-resistance to DST in S. netropsis. This cassette consists of three uncharacterized genes that might be implicated in DNA replication/repair. Knockout of the cassette led to the decrease in the production of DST, while heterologous expression of part of the cassette in S. lividans made it become resistant to both DST and mitomycin C, another DNA-binding agent. More interestingly, homologs of these three genes were found in genomes of other actinomyces that produce DNA-binding antibiotics, suggesting that a novel common mechanism in addition to pumping may enable these strains to resist the cytotoxic metabolites they produced.


Assuntos
Antibacterianos/farmacologia , Reparo do DNA/genética , Replicação do DNA/genética , Distamicinas/farmacologia , Farmacorresistência Bacteriana/genética , Genes Bacterianos/genética , Streptomyces/genética , Antibacterianos/biossíntese , Células Cultivadas , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/farmacologia , Distamicinas/biossíntese , Escherichia coli/genética , Técnicas de Inativação de Genes , Mitomicina/farmacologia , Família Multigênica/genética , Streptomyces/efeitos dos fármacos , Streptomyces lividans/efeitos dos fármacos
16.
Bioorg Med Chem Lett ; 29(5): 685-687, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30728110

RESUMO

To improve the drug-ability of celastrol, a series of PEGylation celastrol (PEGC) were designed and synthesized by conjugation with different kinds of polyethylene glycols (PEGs) with celastrol. Most of PEGCs could easily dissolve in water. In particular, one of them (DC1000) could be dispersed in water to form nanoparticles by self-assembly. The cytotoxic evaluation of PEGCs revealed that some of PEGCs showed more potent cytotoxicity than celastrol, and the molecular weight of PEG parts in PEGCs had apparent influence on their cytotoxic activity. Anti-tumor evaluation in vivo showed DC1000 had higher tumor inhibition rate and better safety than celastrol by intravenous administration with equivalent molar weight. These results revealed PEGylation might be an efficient and economical method to improve the water solubility and safety of celastrol and similar natural products.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Nanopartículas/química , Polietilenoglicóis/química , Triterpenos/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Triterpenos Pentacíclicos , Solubilidade , Água/química
17.
J Immunol ; 199(5): 1817-1826, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28739877

RESUMO

PALLD is an actin cross-linker supporting cellular mechanical tension. However, its involvement in the regulation of phagocytosis, a cellular activity essential for innate immunity and physiological tissue turnover, is unclear. We report that PALLD is highly induced along with all-trans-retinoic acid-induced maturation of myeloid leukemia cells, to promote Ig- or complement-opsonized phagocytosis. PALLD mechanistically facilitates phagocytic receptor clustering by regulating actin polymerization and c-Src dynamic activation during particle binding and early phagosome formation. PALLD is also required at the nascent phagosome to recruit phosphatase oculocerebrorenal syndrome of Lowe, which regulates phosphatidylinositol-4,5-bisphosphate hydrolysis and actin depolymerization to complete phagosome closure. Collectively, our results show a new function for PALLD as a crucial regulator of the early phase of phagocytosis by elaborating dynamic actin polymerization and depolymerization.


Assuntos
Actinas/metabolismo , Proteínas do Citoesqueleto/metabolismo , Células Dendríticas/imunologia , Leucemia Mieloide Aguda/imunologia , Células-Tronco Neoplásicas/fisiologia , Síndrome Oculocerebrorrenal/imunologia , Fagocitose , Fosfoproteínas/metabolismo , Animais , Diferenciação Celular , Linhagem Celular Tumoral , Autorrenovação Celular , Proteínas do Citoesqueleto/genética , Humanos , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Fagossomos/metabolismo , Fosfoproteínas/genética , Monoéster Fosfórico Hidrolases/metabolismo , Polimerização , Agregação de Receptores , Tretinoína/metabolismo
18.
Chem Biodivers ; 16(9): e1900266, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31298476

RESUMO

Two new spliceostatin analogs, designed as spliceostatins J and K (1 and 2), were isolated and identified from the culture of Pseudomonas sp., along with two known ones, FR901464 (3) and spliceostatin E (4). Their structures were elucidated by detailed interpretation of their spectroscopic data, especially 2D-NMR and HR-ESI-MS. Spliceostatin J (1) represented the first example of spliceostatins bearing an unusual hexahydrofuro[3,4-b]furan moiety. Biological assay showed all the isolated compounds except 1 displayed potent cytotoxic activities against two cancer cell lines (MDA-MB-231 and A-549). Structure-activity-relationship studies revealed that the tetrahydropyran ring in spliceostatin analogs was necessary for their bioactive retention.


Assuntos
Antineoplásicos/farmacologia , Furanos/farmacologia , Lactonas/farmacologia , Pseudomonas/química , Pironas/farmacologia , Células A549 , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/química , Furanos/isolamento & purificação , Humanos , Lactonas/química , Lactonas/isolamento & purificação , Estrutura Molecular , Piranos/química , Piranos/isolamento & purificação , Piranos/farmacologia , Pironas/química , Pironas/isolamento & purificação , Compostos de Espiro/química , Compostos de Espiro/isolamento & purificação , Compostos de Espiro/farmacologia , Relação Estrutura-Atividade
19.
Chem Biodivers ; 16(6): e1900062, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30983116

RESUMO

Seven new polyhydroxypregnane glycosides, named cynotophyllosides P-V, together with three known analogs were isolated from the roots of Cynanchum otophyllum C.K.Schneid. Their structures were elucidated by a variety of spectroscopic techniques, as well as acid-catalyzed hydrolysis. All isolates were tested for their immunological activities in vitro against Con A- and LPS-induced proliferation of mice splenocytes. Immunoenhancing (for 1, 9) and immunosuppressive (for 2) activities were observed. Furthermore, cynotophylloside R (3) showed immunomodulatory as it enhanced the proliferation of splenocytes in low concentration and suppressed immune cells in concentration more than 1.0 µg/ml.


Assuntos
Cynanchum/química , Glicosídeos/química , Pregnanos/química , Animais , Proliferação de Células/efeitos dos fármacos , Cynanchum/metabolismo , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Conformação Molecular , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo
20.
Molecules ; 23(11)2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30366473

RESUMO

The One Strain Many Compounds (OSMAC) method was applied to explore the chemical diversities of secondary metabolites produced by Neosartorya fischeri NRRL 181. Four pyripyropenes 1⁻4, eight steroids 5⁻11, and four prenylated indole alkaloids 12⁻15, were obtained from the fungus cultured in petri dishes containing potato dextrose agar (PDA). 1,7,11-trideacetylpyripyropene A (1) and 1,11-dideacetyl pyripyropene A (2) were obtained and spectroscopically characterized (1D, 2D NMR, and HR-ESI-MS) from a natural source for the first time. It offered a sustainable source of these two compounds, which were usually used as starting materials in preparing pyripyropene derivatives. In addition, as compared with all the other naturally occurring pyripyropenes, 1 and 2 possessed unique acetylation patterns that did not follow the established late-step biosynthetic rules of pyripyropenes. The natural occurrence of 1 and 2 in the fungus implied that the timing and order of hydroxylation and acetylation in the late-step biosynthetic pathway of pyripyropenes remained to be revealed. The isolation and identification of 1⁻15 indicated that the OSMAC method could remarkably alter the metabolic profile and enrich the chemical diversities of fungal metabolites. Compounds 1⁻4 exhibited no obvious cytotoxicity against the triple-negative breast cancer cell line MDA-MB-231 as compared with taxol.


Assuntos
Neosartorya/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Alcaloides Indólicos/química , Espectroscopia de Ressonância Magnética , Paclitaxel/farmacologia , Piridinas/química , Sesquiterpenos/química
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