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1.
Nucleic Acids Res ; 52(7): 3886-3895, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38324471

RESUMO

The eukaryotic epigenetic modifications 5-methyldeoxycytosine (5mC) and N6-methyldeoxyadenine (6mA) have indispensable regulatory roles in gene expression and embryonic development. We recently identified an atypical bifunctional dioxygenase CcTet from Coprinopsis cinerea that works on both 5mC and 6mA demethylation. The nonconserved residues Gly331 and Asp337 of CcTet facilitate 6mA accommodation, while D337F unexpectedly abolishes 5mC oxidation activity without interfering 6mA demethylation, indicating a prominent distinct but unclear 5mC oxidation mechanism to the conventional Tet enzymes. Here, we assessed the molecular mechanism of CcTet in catalyzing 5mC oxidation by representing the crystal structure of CcTet-5mC-dsDNA complex. We identified the distinct mechanism by which CcTet recognizes 5mC-dsDNA compared to 6mA-dsDNA substrate. Moreover, Asp337 was found to have a central role in compensating for the loss of a critical 5mC-stablizing H-bond observed in conventional Tet enzymes, and stabilizes 5mC and subsequent intermediates through an H-bond with the N4 atom of the substrates. These findings improve our understanding of Tet enzyme functions in the dsDNA 5mC and 6mA demethylation pathways, and provide useful information for future discovery of small molecular probes targeting Tet enzymes in DNA active demethylation processes.


Assuntos
Agaricales , Dioxigenases , 5-Metilcitosina/metabolismo , Cristalografia por Raios X , Dioxigenases/química , Dioxigenases/genética , Dioxigenases/metabolismo , Desmetilação do DNA , Metilação de DNA , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Ligação de Hidrogênio , Modelos Moleculares , Oxirredução , Especificidade por Substrato , Adenosina/análogos & derivados , Agaricales/enzimologia
2.
Nat Chem Biol ; 18(7): 733-741, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35654845

RESUMO

N6-methyladenosine (6mA) is a DNA modification that has recently been found to play regulatory roles during mammalian early embryo development and mitochondrial transcription. We found that a dioxygenase CcTet from the fungus Coprinopsis cinerea is also a dsDNA 6mA demethylase. It oxidizes 6mA to the intermediate N6-hydroxymethyladenosine (6hmA) with robust activity of 6mA-containing duplex DNA (dsDNA) as well as isolated genomics DNA. Structural characterization revealed that CcTet utilizes three flexible loop regions and two key residues-D337 and G331-in the active pocket to preferentially recognize substrates on dsDNA. A CcTet D337F mutant protein retained the catalytic activity on 6mA but lost activity on 5-methylcytosine. Our findings uncovered a 6mA demethylase that works on dsDNA, suggesting potential 6mA demethylation in fungi and elucidating 6mA recognition and the catalytic mechanism of CcTet. The CcTet D337F mutant protein also provides a chemical biology tool for future functional manipulation of DNA 6mA in vivo.


Assuntos
Dioxigenases , Eucariotos , 5-Metilcitosina/metabolismo , Animais , DNA/metabolismo , Metilação de DNA , Dioxigenases/metabolismo , Eucariotos/metabolismo , Mamíferos/genética , Proteínas Mutantes/genética
3.
Microb Cell Fact ; 23(1): 87, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515152

RESUMO

BACKGROUND: Natural tetramates are a family of hybrid polyketides bearing tetramic acid (pyrrolidine-2,4-dione) moiety exhibiting a broad range of bioactivities. Biosynthesis of tetramates in microorganisms is normally directed by hybrid polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) machineries, which form the tetramic acid ring by recruiting trans- or cis-acting thioesterase-like Dieckmann cyclase in bacteria. There are a group of tetramates with unique skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, which remain to be investigated for their biosynthetic logics. RESULTS: Herein, the tetramate type compounds bripiodionen (BPD) and its new analog, featuring the rare skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, were discovered from the sponge symbiotic bacterial Streptomyces reniochalinae LHW50302. Gene deletion and mutant complementation revealed the production of BPDs being correlated with a PKS-NRPS biosynthetic gene cluster (BGC), in which a Dieckmann cyclase gene bpdE was identified by sit-directed mutations. According to bioinformatic analysis, the tetramic acid moiety of BPDs should be formed on an atypical NRPS module constituted by two discrete proteins, including the C (condensation)-A (adenylation)-T (thiolation) domains of BpdC and the A-T domains of BpdD. Further site-directed mutagenetic analysis confirmed the natural silence of the A domain in BpdC and the functional necessities of the two T domains, therefore suggesting that an unusual aminoacyl transthiolation should occur between the T domains of two NRPS subunits. Additionally, characterization of a LuxR type regulator gene led to seven- to eight-fold increasement of BPDs production. The study presents the first biosynthesis case of the natural molecule with 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione skeleton. Genomic mining using BpdD as probe reveals that the aminoacyl transthiolation between separate NRPS subunits should occur in a certain population of NRPSs in nature.


Assuntos
Vias Biossintéticas , Policetídeo Sintases , Pirrolidinonas , Policetídeo Sintases/metabolismo , Bactérias/metabolismo , Piranos/metabolismo , Esqueleto/metabolismo , Peptídeo Sintases/genética
4.
Eur J Clin Pharmacol ; 80(7): 1017-1027, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38502358

RESUMO

BACKGROUND: The pharmacokinetics of tacrolimus (TAC) show high intra-patient variability (IPV), which is associated with poor long-term outcomes following adult liver transplantation (LT). However, this relationship remains to be confirmed in pediatric liver transplant (PLT) recipients. The present study aimed to investigate the association between TAC IPV and grafts or patient outcomes after pediatric liver transplantion. METHODS: This retrospective study included 848 PLT recipients (including infants) between January, 2016, and June, 2021. The IPV of TAC concentrations was estimated by calculating the coefficient of variation (CV) of trough concentrations in whole blood within 1 month after transplantation. Patients were categorized into two groups, low IPV (CV < 45%) and high IPV (CV ≥ 45%), based on the third quartile of the CV distribution. RESULTS: A total of 848 patients were included in our study. The low CV group included 614 patients, with a mean TAC trough concentration of 8.59 ± 1.65 ng/ml and a median CV of 32.37%. In contrast, the high CV group included 214 patients, the mean TAC trough concentration and median CV were 8.81 ± 2.00 ng/ml and 54.88%, respectively. The median hospital duration was significantly higher in the high CV group (22 days vs. 20 days, P = 0.01). Univariate analysis was performed to evaluate the significant differences in 1-year recipient survival (P = 0.041) and 1-year graft survival (P = 0.005) between the high- and low-CV groups. Moreover, high CV (HR 2.316, 95%CI 1.026-5.231, P = 0.043) and persistent EBV viremia (HR 13.165, 95%CI 3.090-56.081, P < 0.001) were identified as independent risk factors for 1- year mortality after PLT. CONCLUSIONS: PLT recipients with high TAC trough concentration of CV in the first month were associated with poor 1-year outcomes. This CV calculation provides a valuable strategy to monitor TAC exposure.


Assuntos
Imunossupressores , Transplante de Fígado , Tacrolimo , Humanos , Tacrolimo/farmacocinética , Tacrolimo/uso terapêutico , Tacrolimo/sangue , Tacrolimo/administração & dosagem , Masculino , Feminino , Imunossupressores/farmacocinética , Imunossupressores/uso terapêutico , Imunossupressores/sangue , Imunossupressores/administração & dosagem , Estudos Retrospectivos , Lactente , Criança , Pré-Escolar , Rejeição de Enxerto/prevenção & controle , Adolescente , Sobrevivência de Enxerto , Período Pós-Operatório , Resultado do Tratamento
5.
J Nat Prod ; 87(5): 1376-1383, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38662398

RESUMO

A precursor-directed biosynthesis approach led to the accumulation of seven new neoantimycin derivatives (1-7) from Streptomyces conglobatus RJ2. Structure elucidation was conducted using NMR and HRESIMS analysis, and the absolute configuration was determined by advanced Marfey's method, Mosher's analysis, and ECD analysis. The obtained compounds revealed selective and significant cytotoxicity, specifically against colorectal cancer cells bearing the K-ras mutation, with IC50 values ranging from 40 nM to 3.5 µM.


Assuntos
Streptomyces , Streptomyces/química , Streptomyces/metabolismo , Humanos , Estrutura Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Mutação , Ressonância Magnética Nuclear Biomolecular , Compostos Orgânicos
6.
J Nat Prod ; 87(2): 396-403, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38330072

RESUMO

Six new sesquiterpene quinone/hydroquinone meroterpenoids, arenarialins A-F (1-6), were isolated from the marine sponge Dysidea arenaria collected from the South China Sea. Their chemical structures and absolute configurations were determined by HRMS and NMR data analyses coupled with DP4+ and ECD calculations. Arenarialin A (1) features an unprecedented tetracyclic 6/6/5/6 carbon skeleton, whereas arenarialins B-D (2-4) possess two rare secomeroterpene scaffolds. Arenarialins A-F showed inhibitory activity on the production of inflammatory cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages with arenarialin D regulating the NF-κB/MAPK signaling pathway.


Assuntos
Dysidea , Poríferos , Sesquiterpenos , Animais , Dysidea/química , Poríferos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Anti-Inflamatórios/farmacologia , NF-kappa B , Estrutura Molecular
7.
Mar Drugs ; 22(3)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38535441

RESUMO

Inflammatory bowel disease (IBD) is a chronic inflammatory bowel disease with unknown pathogenesis which has been gradually considered a public health challenge worldwide. Peptides derived from Rapana venosa have been shown to have an anti-inflammatory effect. In this study, peptide LLTRAGL derived from Rapana venosa was prepared by a solid phase synthesis technique. The protective effects of LLTRAGL were studied in a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced zebrafish colitis model. The underlying mechanisms of LLTRAGL were predicted and validated by transcriptome, real-time quantitative PCR assays and molecular docking. The results showed that LLTRAGL reduced the number of macrophages migrating to the intestine, enhanced the frequency and rate of intestinal peristalsis and improved intestinal inflammatory damage. Furthermore, transcriptome analysis indicated the key pathways (NOD-like receptor signal pathway and necroptosis pathway) that link the underlying protective effects of LLTRAGL's molecular mechanisms. In addition, the related genes in these pathways exhibited different expressions after TNBS treatment. Finally, molecular docking techniques further verified the RNA-sequencing results. In summary, LLTRAGL exerted protective effects in the model of TNBS-induced colitis zebrafish. Our findings provide valuable information for the future application of LLTRAGL in IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Perciformes , Caramujos , Animais , Peixe-Zebra , Simulação de Acoplamento Molecular , Peptídeos
8.
Mar Drugs ; 22(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38667765

RESUMO

Marine natural products are important sources of novel drugs. In this study, we isolated 4-hydroxyphenylacetic acid (HPA) from the marine-derived fungus Emericellopsis maritima Y39-2. The antithrombotic activity and mechanism of HPA were reported for the first time. Using a zebrafish model, we found that HPA had a strong antithrombotic activity because it can significantly increase cardiac erythrocytes, blood flow velocity, and heart rate, reduce caudal thrombus, and reverse the inflammatory response caused by Arachidonic Acid (AA). Further transcriptome analysis and qRT-PCR validation demonstrated that HPA may regulate autophagy by inhibiting the PI3K/AKT/mTOR signaling pathway to exert antithrombotic effects.


Assuntos
Autofagia , Fibrinolíticos , Fenilacetatos , Peixe-Zebra , Animais , Fenilacetatos/farmacologia , Autofagia/efeitos dos fármacos , Fibrinolíticos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Produtos Biológicos/farmacologia , Trombose/tratamento farmacológico , Modelos Animais de Doenças , Organismos Aquáticos
9.
Chem Biodivers ; : e202400832, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38712949

RESUMO

Two new cytochalasans, marcytoglobosins A (1) and B (2) were isolated from the marine sponge associated fungus Chaetomium globosum 162105, along with six known compounds (3-8). The complete structures of two new compounds were determined based on 1D/2D NMR and HR-MS spectroscopic analyses coupled with ECD calculations. All eight isolates were evaluated for their antibacterial activity. Among them, compounds 3-8 displayed antibacterial effects against Staphylococcus epidermidis, Bacillus thuringiensis, Pseudomonas syringae pv. Actinidiae, Vibrio alginolyticus, and Edwardsiella piscicida with minimum inhibitory concentration (MIC) values ranging from 10 to 25 µg/mL.

10.
Public Health ; 230: 66-72, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38507918

RESUMO

OBJECTIVES: Heart failure (HF) is on the rise as a global health problem, but information on its burden in Asia is limited. This study aimed to assess the burden, trends, and underlying causes of HF in the Asian region. STUDY DESIGN AND METHODS: Data on HF in Asia from 1990 to 2019, including prevalence, years lived with disability (YLD), and underlying causes, were extracted from the Global Burden of Diseases 2019. The cases, the age-standardized prevalence, and the YLD were compared between the age groups, the sexes, the sociodemographic index, and the locations. The proportion of age-standardized prevalence rates of HF attributable to 16 underlying causes was also analyzed. RESULTS: In 2019, the age-standardized prevalence rate of HF per 100,000 persons in Asia was 722.45 (95% uncertainty interval [UI]: 591.97-891.64), with an estimated 31.89 million cases (95% UI: 25.94-39.25). From 1990 to 2019, the prevalence of age-standardized HF in Asia decreased by 4.51%, reflecting the global trend (-7.06%). Age-standardized YLD rates of HF exhibited patterns similar to prevalence rates. Among Asian countries, China had the highest age-standardized prevalence rate, followed by Kuwait and Jordan. Hypertensive heart disease was the leading cause of HF, followed by ischemic heart disease and rheumatic heart disease. CONCLUSIONS: Although the burden of HF in Asia showed a gradual decline between 1990 and 2019, it remains a significant health challenge that requires increased attention. Regional disparities in HF burden are evident, emphasizing the need for urgent prevention and control measures at the regional and national levels.


Assuntos
Pessoas com Deficiência , Insuficiência Cardíaca , Humanos , Carga Global da Doença , Ásia/epidemiologia , Prevalência , Saúde Global , Insuficiência Cardíaca/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida , Incidência
11.
Angew Chem Int Ed Engl ; 63(7): e202313900, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38158383

RESUMO

N1 -methyladenosine (m1 A) is a prevalent post-transcriptional RNA modification, and the distribution and dynamics of the modification play key epitranscriptomic roles in cell development. At present, the human AlkB Fe(II)/α-ketoglutarate-dependent dioxygenase family member ALKBH3 is the only known mRNA m1 A demethylase, but its catalytic mechanism remains unclear. Here, we present the structures of ALKBH3-oligo crosslinked complexes obtained with the assistance of a synthetic antibody crystallization chaperone. Structural and biochemical results showed that ALKBH3 utilized two ß-hairpins (ß4-loop-ß5 and ß'-loop-ß'') and the α2 helix to facilitate single-stranded substrate binding. Moreover, a bubble-like region around Asp194 and a key residue inside the active pocket (Thr133) enabled specific recognition and demethylation of m1 A- and 3-methylcytidine (m3 C)-modified substrates. Mutation of Thr133 to the corresponding residue in the AlkB Fe(II)/α-ketoglutarate-dependent dioxygenase family members FTO or ALKBH5 converted ALKBH3 substrate selectivity from m1 A to N6 -methyladenosine (m6 A), as did Asp194 deletion. Our findings provide a molecular basis for understanding the mechanisms of substrate recognition and m1 A demethylation by ALKBH3. This study is expected to aid structure-guided design of chemical probes for further functional studies and therapeutic applications.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato , RNA , Humanos , RNA/química , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , RNA Mensageiro/metabolismo , Desmetilação , Compostos Ferrosos , Homólogo AlkB 3 da Dioxigenase Dependente de alfa-Cetoglutarato/metabolismo
12.
Nat Prod Rep ; 40(3): 718-749, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36636914

RESUMO

Covering: 2010 to 2021Sesquiterpene quinone/quinols (SQs) are characterized by a C15-sesquiterpenoid unit incorporating a C6-benzoquinone/quinol moiety. Numerous unprecedented carbon skeletons have been constructed with various connection patterns between the two parts. The potent anti-cancer, anti-inflammatory, anti-microbial, anti-viral, and fibrinolytic activities of SQs are associated with their diverse structures. The representative avarol has even entered the stage of clinical phase II research as an anti-HIV agent, and was developed as paramedic medicine against psoriasis. This review provides an overall summary of 558 new natural SQs discovered between 2010 and 2021, including seven groups and sixteen structure-type subgroups, which comprehensively recapitulates their chemical structures, spectral characteristics, source organisms, biological activities, synthesis, and biosynthesis, aiming to expand the application scope of this unique natural product resource.


Assuntos
Hidroquinonas , Sesquiterpenos , Sesquiterpenos/farmacologia , Quinonas/farmacologia , Benzoquinonas
13.
J Med Virol ; 95(3): e28663, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36905287

RESUMO

The spread of disease related to Hepatitis B and C poses a significant public health problem. There have been a few studies that examine the effects of cohort and period on the trend of mortality caused by Hepatitis B and C. This analysis aims to use an age-period-cohort (APC) framework to explore trends in mortality attributed to Hepatitis B and C worldwide and in different socio-demographic index (SDI) regions between 1990 and 2019. The data for this analysis were taken from the Global Burden of Disease study, which was used to perform an APC analysis. The age effects reflect differences in exposure to risk factors at different stages of life. The period effects reflect population-wide exposures at a circumscribed year. The cohort effects indicate different risks across birth cohorts. The results of the analysis include both the net drift and local drift, which are reported as the annual percentage change and that by age group. The age-standardized mortality rate for Hepatitis B declined from 12.36 to 6.74 per 100 000, and for Hepatitis C from 8.45 to 6.67 per 100 000 between 1990 and 2019. The net drifts in mortality were -2.41% (95% confidence interval (CI) -2.47 to -2.34) for Hepatitis B and -1.16% (95% CI, -1.23 to -1.09) for Hepatitis C, with negative local drifts in most age groups. Mortality from Hepatitis B increased with age until 50+ years, while mortality from Hepatitis C rose steadily with age. The period effect for Hepatitis B was profound, suggesting effective national efforts in controlling the disease and the need for similar programs for Hepatitis B and C. Mortality varied across the world and had moderate to weak negative correlations with the SDI, which substantially decreases in the high-middle and middle SDI regions, but has persistently high rates in the low SDI region. Global efforts to manage Hepatitis B and C have shown positive trends, but variations in trends were observed across regions with divergent age, cohort, and period effects. The national efforts of a comprehensive strategy are crucial to further strengthen the elimination of Hepatitis B and C.


Assuntos
Hepatite B , Hepatite C , Humanos , Pessoa de Meia-Idade , Vírus da Hepatite B , Hepatite C/epidemiologia , Fatores de Risco , Hepatite B/epidemiologia , Hepacivirus , Estudos de Coortes , Saúde Global
14.
J Interv Cardiol ; 2023: 4717271, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38028026

RESUMO

Background: Venous thromboembolism (VTE) is a common cardiovascular disease that seriously threatens human lives. Anticoagulant therapy is considered to be the cornerstone of VTE treatment. An increasing number of studies has been updated in the VTE anticoagulation field. However, no bibliometric analyses have assessed these publications comprehensively. Therefore, our study aimed to analyze the global status, hotspots, and trends of anticoagulant therapy for VTE. Methods: The relevant literature on VTE anticoagulation published between 2012 and 2021 was retrieved and collected from the Web of Science Core Collection database. VOSviewer, Cooccurrence Matrix Builder, gCLUTO, and some online visualization tools were adopted for bibliometric analysis. Results: A total of 15,152 related articles were retrieved. In recent years, the research output of VTE anticoagulation gradually increased. The United States was the most productive country. International cooperation is concentrated in North America and Europe; the most influential documents, journals, authors, and organizations were also from these two continents. Research hotspots mainly focus on clinical guidelines, VTE in special populations, non-vitamin K oral anticoagulants (NOACs), and parenteral anticoagulation. The research frontiers and trends include the assessment of NOACs and the antithrombotic management of VTE complicated with coronavirus disease 2019 (COVID-19). Conclusion: This bibliometric analysis provides a systematic overview of the VTE anticoagulation research, which will facilitate researchers to better understand the situation of VTE anticoagulation. Future studies should be dedicated to NOACs application and VTE-combined COVID-19 patients.


Assuntos
COVID-19 , Tromboembolia Venosa , Humanos , Administração Oral , Anticoagulantes/uso terapêutico , COVID-19/complicações , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/prevenção & controle , Tromboembolia Venosa/etiologia , Vitamina K/uso terapêutico , Bibliometria
15.
Eur J Clin Pharmacol ; 79(12): 1631-1639, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37755492

RESUMO

BACKGROUND: Direct oral anticoagulants (DOACs) are increasingly recommended over warfarin in stroke prevention for patients with non-valvular atrial fibrillation (AF). However, there is an important evidence gap in choosing the most appropriate DOAC for Chinese patients in clinical practice. METHODS: A multi-criteria decision analysis (MCDA) was adopted to build a scoring framework. Attributes and criteria were identified and determined by a scoping literature review, two rounds of Delphi surveys, and a consensus meeting. Weights of each attribute and criterion in the framework were determined using analytic hierarchy process (AHP). Evidence was collected based on the domestic or at least Asian data. Scoring methods for each criterion were developed depended on their characteristics and determined with an expert consensus meeting. Comprehensive scores of each DOAC were calculated based on the utility scores of each criterion and their corresponding weights. RESULTS: A total of 5 attributes, including safety, efficacy, costs/cost-effectiveness, suitability, and accessibility, were determined, and 16 criteria were under the 5 attributes. The safety and efficacy were ranked as the top two important attributes with the weights of 38.8% and 35.9%, respectively, while the suitability received the lowest weight of 7.9%. The comprehensive score for edoxaban was the highest (72.3), followed by dabigatran (49.7), rivaroxaban (37.9), and apixaban (35.8). CONCLUSIONS: This study provided a scoring framework developed for comprehensive evaluation of DOACs in China. The ranking of DOACs could help to support the decision-making in clinical practice. The framework could provide a reference for comprehensive evaluation of other drugs.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Anticoagulantes/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/tratamento farmacológico , Varfarina/uso terapêutico , Rivaroxabana/uso terapêutico , Dabigatrana/uso terapêutico , Piridonas/uso terapêutico , Administração Oral
16.
J Nat Prod ; 86(1): 45-51, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36524671

RESUMO

Burkitt's lymphoma (BL) has a particularly extremely poor prognosis and the fastest growth rate among human tumors, and the development of new drugs for the treatment of BL is urgently needed. In this study, the cytotoxic properties of 3,7-bis(3,5-dimethylphenyl)-aaptamine (AP-51), a new semisynthetic alkaloid derived from the marine natural product aapatamine, were investigated using BL cell lines. Our results showed that AP-51 inhibited the proliferation of Daudi and Raji cells with IC50 values of 3.48 and 2.07 µM, respectively. Flow cytometry and Western blot analyses showed that AP-51 initiated G0/G1 phase arrest by modulating the expression of cyclin-dependent kinases (CDKs). AP-51 also induced apoptosis, as demonstrated by nuclear fragmentation, downregulation of BCL-XL and Mcl-1, and upregulation of cleaved caspase-9, cleaved caspase-3, cleaved-PARP, and cytochrome c, the markers of apoptosis regulated via the mitochondrial pathway. When it comes to mitochondria, AP-51 treatment also significantly increased the levels of intracellular mitochondrial superoxide, decreased ATP content, and reduced the expression of ATP synthase, as well as the expression of the mitochondrial respiratory chain complexes. Finally, AP-51 treatment significantly inhibited the PI3K/AKT/mTOR signaling pathway, which was shown to be associated with the induction of apoptosis. Collectively, these findings indicated that AP-51 initiated cell cycle arrest, induced apoptosis, caused mitochondrial dysfunction, and decreased the phosphorylation of PI3K/AKT/mTOR signaling pathway-related proteins and the protein levels of C-MYC, suggesting that AP-51 has therapeutic potential as a possible treatment for Burkitt's lymphoma.


Assuntos
Alcaloides , Antineoplásicos , Linfoma de Burkitt , Poríferos , Animais , Humanos , Trifosfato de Adenosina , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Linhagem Celular Tumoral , Proliferação de Células , Mitocôndrias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Poríferos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
17.
J Nat Prod ; 86(7): 1754-1760, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37335557

RESUMO

Phyllospongianes A-E (1-5), five new scalarane derivatives featuring an unprecedented 6/6/6/5 tetracyclic dinorscalarane scaffold, along with the known probable biogenetic precursor, 12-deacetylscalaradial (6), were isolated from the marine sponge Phyllospongia foliascens. The structures of the isolated compounds were determined by analysis of spectroscopic data and electronic circular dichroism experiments. Compounds 1-5 are the first 6/6/6/5 tetracyclic scalarane derivatives to be reported within the scalarane family. Compounds 1, 2, and 4 exhibited antibacterial activity against Vibrio vulnificus, Vibrio parahemolyticus, Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis, and Pseudomonas aeruginosa with MIC values ranging from 1 to 8 µg/mL. Furthermore, compound 3 exhibited significant cytotoxic activity on MDA-MB-231, HepG2, C4-2-ENZ, MCF-7, H460, and HT-29 cancer cell lines with IC50 values in the range between 0.7 and 13.2 µM.


Assuntos
Antineoplásicos , Poríferos , Animais , Sesterterpenos/química , Poríferos/química , Antineoplásicos/química , Antibacterianos/farmacologia , Bacillus subtilis , Escherichia coli , Estrutura Molecular
18.
J Nat Prod ; 86(7): 1708-1714, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37317791

RESUMO

Cyanogripeptides A-C (1-3), three new cyclolipopeptides with unusual ß-methyl-leucine residues, were identified from an Actinoalloteichus cyanogriseus LHW52806 using an LC-MS-guided strategy. The structures of compounds 1-3 were elucidated by 1D/2D NMR, HR-MS/MS, and the advanced Marfey's method. The absolute configuration of the ß-methyl-leucine residue was determined by a combination of stereoselective biosynthesis of (2S,3R)-ß-methyl-leucine, racemization to its epimer (2R,3R)-ß-methyl-leucine, and the advanced Marfey's method. The biosynthetic pathway of cyanogripeptides was deduced by analyzing the genome of A. cyanogriseus LHW52806. Compound 3 exhibited antibacterial activity against Helicobacter pylori G27, Helicobacter pylori 26695, and Mycolicibacterium smegmatis ATCC607 with MIC values of 32 µg/mL.


Assuntos
Actinobacteria , Actinomycetales , Cromatografia Líquida , Espectrometria de Massas em Tandem , Leucina , Estrutura Molecular
19.
Bioorg Chem ; 139: 106699, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37390633

RESUMO

A chemical investigation of the marine sponge Phakellia sp. from the South China Sea yielded five new cyclopeptides, phakellisins A-E (1-5). Structures of these compounds were determined by comprehensive analysis of 1D/2D NMR, HRESIMS/MS spectroscopic data and the advanced Marfey's method. All compounds were evaluated for their cytotoxic activity. Compound 1 showed a strong inhibitory activity against WSU-DLCL-2 cells with an IC50 value of 5.25 ± 0.2 µM by induction of G0/G1 cell cycle arrest and apoptosis.


Assuntos
Peptídeos Cíclicos , Poríferos , Animais , Cromatografia Líquida , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química , Espectrometria de Massas em Tandem , Poríferos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
20.
Mar Drugs ; 21(10)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37888442

RESUMO

Eight new scalarane sesterterpenes, phyllofenones F-M (1-8), together with two known analogues, carteriofenones B and A (9-10), were isolated from the marine sponge Phyllospongia foliascens collected from the South China Sea. The structures of these compounds were determined based on extensive spectroscopic and quantum chemical calculation analysis. The antibacterial and cytotoxic activity of these compounds was evaluated. Among them, only compounds 4 and 6 displayed weak inhibitory activity against Staphylococcus aureus and Escherichia coli, with MIC values of 16 µg/mL and 8 µg/mL, respectively. Compounds 1-10 exhibited cytotoxic activity against the HeLa, HCT-116, H460, and SW1990 cancer cell lines, with IC50 values ranging from 3.4 to 19.8 µM.


Assuntos
Antineoplásicos , Poríferos , Animais , Humanos , Sesterterpenos/química , Poríferos/química , Espectroscopia de Ressonância Magnética , Antineoplásicos/química , Células HeLa , Escherichia coli , Estrutura Molecular
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