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1.
Cureus ; 16(2): e53469, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38435179

RESUMO

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an autosomal dominant genetic disorder of the small arteries that causes ischemic vascular events, subcortical dementia, behavioral changes, and migraine-like headaches. It is caused by a mutation in the NOTCH3 gene; this disease was first described in 1955 by van Bogaert. We present a 29-year-old woman who presented to the neurology department. She has no history of chronic degenerative diseases. She has been complaining of migraine-like headaches for the past six months. She has cognitive impairment with arithmetic and executive function deficits on neurological examination. Blood biometry and blood chemistry are within normal parameters in her laboratory studies. A viral panel and immunological profile were also performed and were not reactive. A lumbar puncture was performed, and the composition of the cerebrospinal fluid was within normal limits. An MRI was performed, which showed bilateral and symmetric white matter hyperintensities consistent with CADASIL syndrome. There is no specific treatment. Management of these patients is based on symptom control. Neurological sequelae have an important impact on the quality of life and mortality of these patients. For this reason, pharmacological preventive therapies have been sought with controversial evidence.

2.
Bioorg Med Chem Lett ; 98: 129592, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38101651

RESUMO

We prepared a series of cinnamoyl-containing furanones by an affordable and short synthesis. The nineteen compounds hold a variety of substituents including electron-donating, electron-withdrawing, bulky and meta-substituted phenyls, as well as heterocyclic rings. Compounds showed antibiofilm activity in S. aureus, K. pneumoniae and, more pronounced, against P. aeruginosa. The disruption of quorum sensing (QS) was tested using the violacein test and molecular docking predicted the antagonism of LasR as a plausible mechanism of action. The trimethoxylated and diene derivatives showed the best antibiofilm and anti-QS properties, thus becoming candidates for further modifications.


Assuntos
Lactonas , Staphylococcus aureus , Antibacterianos/farmacologia , Proteínas de Bactérias/farmacologia , Biofilmes , Lactonas/farmacologia , Simulação de Acoplamento Molecular , Pseudomonas aeruginosa , Percepção de Quorum
3.
J Med Chem ; 66(23): 16222-16234, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38051546

RESUMO

Duclauxin (1) from Talaromyces sp. IQ-313 was reported as a putative allosteric modulator of human recombinant protein tyrosine phosphatase 1B (400 amino acids) (hPTP1B1-400), a validated target for the treatment of type II diabetes. Based on these findings, a one-strain-many-compound (OSMAC) experiment on the IQ-313 strain generated derivatives 5a, 6, and 7. Moreover, a one-/two-step semisynthetic approach guided by docking toward hPTP1B1-400 produced 38 analogs, a series (A) incorporating a lactam functionalization at C-1 (8a-15a, 36a, and 37a) and a series (B) containing a lactam at C-1 and an extra unsaturation between C-7 and C-8 (5b, 11b-37b). In vitro evaluation and structure-activity relationship (SAR) analysis revealed that analogs from the B series are up to 10-fold more active than 1 and derivatives from the A series. Furthermore, duclauxin (1) and 36b were assessed for their potential acute toxicity, estimating their LD50 to be higher than 300 mg/kg. Moreover, 36b significantly reduced glycemia in an insulin tolerance test in mice, suggesting that its mechanism of action is through the PTP1B inhibition.


Assuntos
Diabetes Mellitus Tipo 2 , Camundongos , Humanos , Animais , Diabetes Mellitus Tipo 2/metabolismo , Relação Estrutura-Atividade , Lactamas , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo
4.
J Nat Prod ; 86(11): 2423-2434, 2023 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875020

RESUMO

Natural product reisolation is a bottleneck when discovering new bioactive chemical entities from nature. To overcome this issue, multi-informative approaches integrating several layers of data have been applied with promising results. In this study, integration of taxonomy, nontargeted metabolomics, and bioactivity information resulted in the selection of Scytalidium sp. IQ-074 and Diaporthe sp. IQ-053 to isolate new natural products active against hPTP1B1-400 and repurpose others as antibiotics. Strain IQ-074 was selected based on the hypothesis that investigating poorly studied and highly metabolic taxa could lead to the isolation of new chemical entities. A chemical investigation of IQ-074 resulted in the isolation of papyracillic acid A (14), 7-deoxypapyracillic acid A (15a and 15b), and linear polyketides scytalpolyols A-D (16-19). Compound 17 inhibited hPTP1B1-400 with a half-maximal inhibitory concentration of 27.0 ± 1.7 µM. Diaporthe sp. IQ-053 was selected based on its antibacterial properties against pathogenic strains. Its chemical investigation yielded dothiorelones A (20) and I (21), cytosporones B (22) and C (23), pestalotiopsone B (24), and diaporthalasin (25). Compounds 22 and 25 inhibited the growth of Staphylococcus aureus and Staphylococcus epidermidis 42R and moderately inhibited the growth of Acinetobacter baumannii A564, a pandrug-resistant bacterium.


Assuntos
Ascomicetos , Produtos Biológicos , Infecções Estafilocócicas , Produtos Biológicos/farmacologia , Antibacterianos/química , Staphylococcus aureus , Ascomicetos/química , Testes de Sensibilidade Microbiana
5.
Proc Natl Acad Sci U S A ; 120(25): e2219373120, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37319116

RESUMO

Fungus-growing ants depend on a fungal mutualist that can fall prey to fungal pathogens. This mutualist is cultivated by these ants in structures called fungus gardens. Ants exhibit weeding behaviors that keep their fungus gardens healthy by physically removing compromised pieces. However, how ants detect diseases of their fungus gardens is unknown. Here, we applied the logic of Koch's postulates using environmental fungal community gene sequencing, fungal isolation, and laboratory infection experiments to establish that Trichoderma spp. can act as previously unrecognized pathogens of Trachymyrmex septentrionalis fungus gardens. Our environmental data showed that Trichoderma are the most abundant noncultivar fungi in wild T. septentrionalis fungus gardens. We further determined that metabolites produced by Trichoderma induce an ant weeding response that mirrors their response to live Trichoderma. Combining ant behavioral experiments with bioactivity-guided fractionation and statistical prioritization of metabolites in Trichoderma extracts demonstrated that T. septentrionalis ants weed in response to peptaibols, a specific class of secondary metabolites known to be produced by Trichoderma fungi. Similar assays conducted using purified peptaibols, including the two previously undescribed peptaibols trichokindins VIII and IX, suggested that weeding is likely induced by peptaibols as a class rather than by a single peptaibol metabolite. In addition to their presence in laboratory experiments, we detected peptaibols in wild fungus gardens. Our combination of environmental data and laboratory infection experiments strongly support that peptaibols act as chemical cues of Trichoderma pathogenesis in T. septentrionalis fungus gardens.


Assuntos
Formigas , Infecção Laboratorial , Trichoderma , Animais , Formigas/fisiologia , Jardins , Sinais (Psicologia) , Simbiose , Peptaibols
6.
Fitoterapia ; 162: 105265, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35963484

RESUMO

Compounds derived from natural sources have been major contributors to the area of cancer chemotherapy for decades. As part of an ongoing effort to discover anticancer drug leads from tropical plants, a large-scale collection of Glycosmis ovoidea Pierre (Rutaceae), was made at Nui Chua National Park, Vietnam. Activity-guided fractionation of the chloroform-soluble fractions led to the isolation of nine coumarins, including the new compound, 1-(7-methoxy-2-oxo-2H-chromen-8-yl)-3-methyl-1-oxobut-2-en-2-yl (S)-2-methylbutanoate (1). An close analogue of 1, namely, kincuongin (2), was deemed as non-cytotoxic (IC50 > 10 µM) against five different cancer cell lines. However, co-administration of kimcuongin (2) showed an approximately 100 times potentiation of the MCF-7 breast cancer cell cytotoxicity of the previously reported flavonoid, 5,3'-dihydroxy-3,6,7,8,4'-pentamethoxyflavone (10). To provide a mechanistic basis for the cancer cell line inhibition enhancement observed, an initial in silico study on compound 10 indicated that it interacts with isoforms of the NF-κB complex. In a confirmatory western blot experiment conducted, kimcuongin (2) was found to potentiate the effects of flavone 10 in inhibiting both NF-κB and PARP-1. In vivo investigations using a zebrafish (Danio rerio) model showed that compounds 2, 3, 5, and 6 did not exhibit any discernible toxicity at concentrations up to 50 µM.


Assuntos
Antineoplásicos , Flavonas , Rutaceae , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Clorofórmio , Cumarínicos/farmacologia , Estrutura Molecular , NF-kappa B , Inibidores de Poli(ADP-Ribose) Polimerases , Vietnã , Peixe-Zebra
7.
Planta Med ; 88(9-10): 702-720, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35697058

RESUMO

The discovery of novel antimicrobials has significantly slowed down over the last three decades. At the same time, humans rely increasingly on antimicrobials because of the progressive antimicrobial resistance in medical practices, human communities, and the environment. Data mining is currently considered a promising option in the discovery of new antibiotics. Some of the advantages of data mining are the ability to predict chemical structures from sequence data, anticipation of the presence of novel metabolites, the understanding of gene evolution, and the corroboration of data from multiple omics technologies. This review analyzes the state-of-the-art for data mining in the fields of bacteria, fungi, and plant genomic data, as well as metabologenomics. It also summarizes some of the most recent research accomplishments in the field, all pinpointing to innovation through uncovering and implementing the next generation of antimicrobials.


Assuntos
Anti-Infecciosos , Produtos Biológicos , Antibacterianos/química , Anti-Infecciosos/farmacologia , Bactérias , Produtos Biológicos/química , Mineração de Dados , Humanos
8.
Bioorg Chem ; 115: 105166, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34384957

RESUMO

Protein tyrosine phosphatase 1B (PTP1B) is an active target for developing drugs to treat type II diabetes, obesity, and cancer. However, in the past, research programs targeting this enzyme focused on discovering inhibitors of truncated models (hPTP1B1-282, hPTP1B1-298, or hPTP1B1-321), losing valuable information about the ligands' mechanism of inhibition and selectivity. Nevertheless, finding an allosteric site in hPTP1B1-321, and the full-length (hPTP1B1-400) protein expression, have shifted the strategies to discover new PTP1B inhibitors. Accordingly, as part of a research program directed at finding non-competitive inhibitors of hPTP1B1-400 from Pezizomycotina, the extract of Penicillium sp. (IQ-429) was chemically investigated. This study led to xanthoepocin (1) isolation, which was elucidated by means of spectroscopic and spectrometric data. The absolute configuration of 1 was determined to be 7R8S9R7'R8'S9'R by comparing the theoretical and experimental ECD spectra and by GIAO-NMR DP4 + statistical analysis. Xanthoepocin (1) inhibited the phosphatase activity of hPTP1B1-400 (IC50 value of 8.8 ± 1.0 µM) in a mixed type fashion, with ki and αki values of 5.5  and 6.6 µM, respectively. Docking xanthoepocin (1) with a homologated model of hPTP1B1-400 indicated that it binds in a pocket different from the catalytic triad at the interface of the N and C-terminal domains. Molecular dynamics (MD) simulations showed that 1 locks the WPD loop of hPTP1B1-400 in a closed conformation, avoiding substrate binding, products release, and catalysis, suggesting an allosteric modulation triggered by large-scale conformational and dynamics changes. Intrinsic quenching fluorescence experiments indicated that 1 behaves like a static quencher of hPTP1B1-400 (KSV = 1.1 × 105 M-1), and corroborated that it binds to the enzyme with an affinity constant (ka) of 3.7 × 105 M-1. Finally, the drug-likeness and medicinal chemistry friendliness of 1 were predicted with SwissADME.


Assuntos
Inibidores Enzimáticos/química , Compostos de Epóxi/química , Penicillium/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Pironas/química , Regulação Alostérica/efeitos dos fármacos , Sítios de Ligação , Domínio Catalítico , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Compostos de Epóxi/metabolismo , Compostos de Epóxi/farmacologia , Meia-Vida , Humanos , Cinética , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Penicillium/metabolismo , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Pironas/metabolismo , Pironas/farmacologia , Termodinâmica
9.
Arch Cardiol Mex ; 91(1): 66-72, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33661879

RESUMO

Objective: To determine the association of cardiovascular diseases with falls in the geriatric population. Methods: Original, Transversal and analytical study. Elderly patients who attend the external consultation of the Geriatrics service, older than 65 years, with falls history, perform comprehensive geriatric assessment to indentify causes of falls in the period from March 2018 to June 2019. We perform measures of central tendency, chi-square test X2 for qualitative variables, we performed linear regression model. Results: A total of 669 patients were included, the analysis shows association with frailty [OR 1.65 (95% CI 1.37-3.77), p <0.05], Heart Failure [OR 1.02, (95% CI, 0.68 - 1.54), p < 0.05 ], the logistic regression analysis with the variables (Fragility, SAH, es: DM2, AMI, Stroke, AF, postural hypotensive syncope, Hypothyroidism, Dyslipidemia, and HF) shows that the probability of falling is 57%. Conclusion: Cardiovascular diseases have a high prevalence in the population studied and increase the risk of falls. Individually analyzed cardiovascular diseases do not show an association with the syndrome of falls in the elderly, except for frailty, which proved to be an independent factor that increases the risk of falls with an OR 1.65. When analyzing them together, the risk of falling increases up to 57%. It is necessary to correctly identify and treat cardiovascular diseases in the elderly.


Objetivo: Determinar la asociación de las caídas con las enfermedades cardiovasculares en la población geriátrica. Métodos: Estudio original, transversal y analítico. Se incluyó a los pacientes que acuden a la consulta externa del Servicio de Geriatría, mayores de 65 años, con antecedentes de caídas, se realizó una evaluación geriátrica integral para identificar las causas de las caídas en el periodo de marzo de 2018 a junio de 2019. Realizamos medidas de tendencia central, chi cuadrada (prueba c2) para variables cualitativas, realizamos modelo de regresión lineal. Resultados: Se incluyeron un total de 669 pacientes. El análisis muestra asociación con fragilidad (odds ratio [OR]: 1.65; intervalo de confianza del 95% [IC 95%]: 1.37-3.77); p < 0.05]), insuficiencia cardiaca (OR: 1.02; IC 95%: 0.68-1.54); p < 0.05). El análisis de regresión logística con las variables fragilidad, HAS, DM2, IAM, EVC, FA, síncope por hipotensión ortostática, hipotiroidismo, dislipidemia e insuficiencia cardiaca (IC) muestra que la probabilidad de caídas es del 57%. Conclusión: Las enfermedades cardiovasculares tienen una alta prevalencia en la población estudiada y aumentan el riesgo de caídas. Las enfermedades cardiovasculares analizadas individualmente no muestran una asociación con el síndrome de caídas en los ancianos, a excepción de la fragilidad, que resultó ser un factor independiente que aumenta el riesgo de caídas con una OR de 1.65. Al analizarlas juntas, el riesgo de caídas se incrementa en un 57%. Es necesario identificar y tratar correctamente las enfermedades cardiovasculares en los ancianos.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Doenças Cardiovasculares/epidemiologia , Avaliação Geriátrica , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Medição de Risco
10.
Arch. cardiol. Méx ; 91(1): 66-72, ene.-mar. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1152862

RESUMO

Abstract Objective: To determine the association of cardiovascular diseases with falls in the geriatric population. Methods: Original, Transversal and analytical study. Elderly patients who attend the external consultation of the Geriatrics service, older than 65 years, with falls history, perform comprehensive geriatric assessment to indentify causes of falls in the period from March 2018 to June 2019. We perform measures of central tendency, chi-square test X2 for qualitative variables, we performed linear regression model. Results: A total of 669 patients were included, the analysis shows association with frailty [OR 1.65 (95% CI 1.37-3.77), p <0.05], Heart Failure [OR 1.02, (95% CI, 0.68 - 1.54), p < 0.05 ], the logistic regression analysis with the variables (Fragility, SAH, es: DM2, AMI, Stroke, AF, postural hypotensive syncope, Hypothyroidism, Dyslipidemia, and HF) shows that the probability of falling is 57%. Conclusion: Cardiovascular diseases have a high prevalence in the population studied and increase the risk of falls. Individually analyzed cardiovascular diseases do not show an association with the syndrome of falls in the elderly, except for frailty, which proved to be an independent factor that increases the risk of falls with an OR 1.65. When analyzing them together, the risk of falling increases up to 57%. It is necessary to correctly identify and treat cardiovascular diseases in the elderly.


Resumen Objetivo: Determinar la asociación de las caídas con las enfermedades cardiovasculares en la población geriátrica. Métodos: Estudio original, transversal y analítico. Se incluyó a los pacientes que acuden a la consulta externa del Servicio de Geriatría, mayores de 65 años, con antecedentes de caídas, se realizó una evaluación geriátrica integral para identificar las causas de las caídas en el periodo de marzo de 2018 a junio de 2019. Realizamos medidas de tendencia central, chi cuadrada (prueba c2) para variables cualitativas, realizamos modelo de regresión lineal. Resultados: Se incluyeron un total de 669 pacientes. El análisis muestra asociación con fragilidad (odds ratio [OR]: 1.65; intervalo de confianza del 95% [IC 95%]: 1.37-3.77); p < 0.05]), insuficiencia cardiaca (OR: 1.02; IC 95%: 0.68-1.54); p < 0.05). El análisis de regresión logística con las variables fragilidad, HAS, DM2, IAM, EVC, FA, síncope por hipotensión ortostática, hipotiroidismo, dislipidemia e insuficiencia cardiaca (IC) muestra que la probabilidad de caídas es del 57%. Conclusión: Las enfermedades cardiovasculares tienen una alta prevalencia en la población estudiada y aumentan el riesgo de caídas. Las enfermedades cardiovasculares analizadas individualmente no muestran una asociación con el síndrome de caídas en los ancianos, a excepción de la fragilidad, que resultó ser un factor independiente que aumenta el riesgo de caídas con una OR de 1.65. Al analizarlas juntas, el riesgo de caídas se incrementa en un 57%. Es necesario identificar y tratar correctamente las enfermedades cardiovasculares en los ancianos.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Acidentes por Quedas/estatística & dados numéricos , Doenças Cardiovasculares/epidemiologia , Avaliação Geriátrica , Estudos Transversais , Medição de Risco
11.
Phytochemistry ; 184: 112664, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33524855

RESUMO

From solid rice-based cultures of Malbranchea albolutea, three undescribed ardeemins and sartoryglabrins analogs were discovered and named alboluteins A-C. 1H-Indole-3-carbaldehyde, and anthranilic acid were also isolated. 1D and 2D-NMR techniques, as well as DFT-calculated chemical shifts, allowed characterizing alboluteins A-C. Testing these compounds against PTP1B indicated their inhibitory activity with IC50's ranging from 19 to 129 µM (ursolic acid IC50 = 29.8 µM, positive control). Kinetic analysis revealed that albolutein C behaved as a non-competitive inhibitor. Docking studies of alboluteins A-C into the crystal structure of PTP1B (PDB ID: 1T49) predicted that all compounds prefer to bind at the allosteric site of the enzyme, with Ki values of 2.02 × 10-4, 1.31 × 10-4, and 2.67 × 10-4 mM, respectively. Molecular dynamic studies indicated that the active compounds remained tied to the enzyme with good binding energy.


Assuntos
Inibidores Enzimáticos , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Inibidores Enzimáticos/farmacologia , Fungos/metabolismo , Cinética , Simulação de Acoplamento Molecular , Onygenales , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo
12.
Anticancer Res ; 40(12): 6637-6647, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33288558

RESUMO

BACKGROUND/AIM: This study aimed to uncover the effects of (+)-betulin on the NF-κB-apoptotic pathway in MDA-MB-231 cells, and determine its toxicity and protein expression in vivo. MATERIALS AND METHODS: Cell cytotoxicity and toxicity were determined using the SRB assay and a zebrafish model, respectively. Western blot, mitochondrial transmembrane potential (MTP), and computational modeling analysis were performed. RESULTS: (+)-betulin inhibited the growth of MDA-MB-231 cells, but did not induce toxicity in zebrafish. (+)-Betulin inhibited the activity of NF-κB p65 in silico and in vitro. In cells, (+)-betulin down-regulated NF-κB p50 and 65, IKKα and ß, ICAM-1 and bcl-2 expressions. Cell co-treatment with (+)-betulin and TNFα increased the (+)-betulin cytotoxic potential. Moreover, (+)-betulin induced the loss of MTP. Furthermore, (+)-betulin, in zebrafish, down-regulated the expression of NF-κB p65, IKKα, ΙΚΚß and procaspase-3. CONCLUSION: The results contribute to the understanding of the mode of action on apoptosis induction by inhibiting NF-κB pathway in MDA-MB-231 cells.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , NF-kappa B/antagonistas & inibidores , Triterpenos/farmacologia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Triterpenos/química , Fator de Necrose Tumoral alfa/farmacologia , Peixe-Zebra
13.
Bioorg Med Chem ; 28(24): 115817, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33120077

RESUMO

Protein tyrosine phosphatase 1B (PTP1B) is a validated target for developing antiobesity, antidiabetic and anticancer drugs. Over the past years, several inhibitors of PTP1B have been discovered; however, none has been approved by the drug regulatory agencies. Interestingly, the research programs focused on discovering PTP1B inhibitors typically use truncated structures of the protein (PTP1B1-300, 1-300 amino acids), leading to the loss of valuable information about the inhibition and selectivity of ligands and repeatedly misleading the optimization of putative drug leads. Up to date, only six inhibitors of the full-length protein (hPTP1B1-400), with affinity constants ranging from 1.3 × 104 to 3.3 × 106 M-1, have been reported. Towards the discovery of new ligands of the full-length human PTP1B (hPTP1B1-400) from natural sources, herein we describe the isolation of a γ-lactone (1, butyrolactone I) from the fungus Aspergillus terreus, as well as the semisynthesis, inhibitory properties (in vitro and in silico), and the structure-activity relationship of a set of butyrolactone derivatives (1 and 2, and 6-12) as hPTP1B1-400 inhibitors, as well as the affinity constant (ka = 2.2 × 105 M-1) of the 1-hPTP1B1-400 complex, which was determined by fluorescence quenching experiments, after the inner filter effect correction.


Assuntos
4-Butirolactona/análogos & derivados , Inibidores Enzimáticos/síntese química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , 4-Butirolactona/química , 4-Butirolactona/metabolismo , Aspergillus/química , Aspergillus/metabolismo , Sítios de Ligação , Desenho de Fármacos , Inibidores Enzimáticos/metabolismo , Humanos , Simulação de Acoplamento Molecular , Análise de Componente Principal , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
14.
Fitoterapia ; 146: 104706, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32829012

RESUMO

Thirteen compounds were isolated from the methanolic extract of the leaves of Androcymbium palaestinum Baker (Colchicaceae). Of these, three were new, two were new natural products, and eight were known. The new isolated compounds were (+)-1-demethylandrocine (5), (-)-andropalaestine (8), and (+)-2-demethyl-ß-lumicolchicone (10), while the new natural products were (+)-O-methylkreysigine-N-oxide (3) and (+)-O,O-dimethylautumnaline (9). Moreover, two known compounds are reported for the first time from this species, specifically (-)-colchicine (11) and (-)-3-demethyldemecolcine (13). The structures of the isolated compounds were elucidated using a series of spectroscopic and spectrometric techniques, principally HRESIMS, 1D-NMR (1H and 13C NMR) and 2D-NMR (COSY, edited-HSQC, and HMBC). ECD spectroscopy was used for assigning the absolute configurations of compounds 3, 5, and 10. The cytotoxic activities of the isolated compounds were evaluated using the MDA-MB-435 (melanoma), MDA-MB-231 (breast), and OVCAR3 (ovary) cancer cell lines. Compound 11 was the most potent against all tested cell lines, with IC50 values of 12, 95 and 23 nM, respectively.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Colchicaceae/química , Isoquinolinas/farmacologia , Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Isoquinolinas/isolamento & purificação , Jordânia , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química
15.
J Nat Prod ; 83(7): 2212-2220, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32597650

RESUMO

Preliminary analysis of the mass spectrometric (MS) and NMR spectroscopic data of the primary fractions from the biologically active extract of Salvia decora revealed spectra that are characteristic for neo-clerodane-type diterpenoids. MS-guided isolation of the bioactive fractions led to the isolation of three new chemical entities, including two hydroxy-neo-clerodanes (1 and 2) and one acylated 5,10-seco-neo-clerodane (3), along with three known diterpenoids (4-6), ursolic acid (7), and eupatorin (8). The structures of the new compounds were established by analysis of the 1D and 2D NMR and MS data, whereas their absolute configuration was deduced using a combination of experimental and theoretical ECD data and confirmed by X-ray crystallography (1 and 4). Furthermore, compounds 1, 3, 4, and 6-8 were evaluated as hPTP1B1-400 (human protein tyrosine phosphatase) inhibitors, where 7 showed the best activity, with an IC50 value in the lower µM range. Additionally, compound 7 was evaluated as an α-glucosidase inhibitor. The affinity constant of the 7-hPTP1B1-400 complex was determined by quenching fluorescence experiments (ka = 1.3 × 104 M-1), while the stoichiometry ratio (1:1 protein-ligand) was determined by a continuous variation method.


Assuntos
Diterpenos Clerodânicos/isolamento & purificação , Salvia/química , Cristalografia por Raios X , Diterpenos Clerodânicos/química , Estrutura Molecular , Análise Espectral/métodos
16.
Bioorg Chem ; 101: 103893, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32492551

RESUMO

A critical biological event that contributes to the appearance and progress of cancer and diabetes is the reversible phosphorylation of proteins, a process controlled by protein tyrosine-kinases (PTKs) and protein tyrosine-phosphatases (PTPs). Within the PTPs, PTP1B has gained significant interest since it is a validated target in drug discovery. Indeed, several PTP1B inhibitors have been developed, from both, synthesis and natural products. However, none have been approved by the FDA, due to their poor selectivity and/or pharmacokinetic properties. One of the most significant challenges to the discovery of PTP1B inhibitors (in vitro or in silico) is the use of truncated structures (PTP1B1-300), missing valuable information about the mechanisms of inhibition, and selectivity of ligands. The present study describes the biochemical characterization of a full-length PTP1B (hPTP1B1-400), as well as the description of phenalenones 1-4 and ursolic acid (5) as allosteric modulators. Compounds 1-5 showed inhibitory potential on hPTP1B1-400, with IC50 values ranging from 12.7 to 82.1 µM. Kinetic studies showed that 1 and 5 behave as mixed and non-competitive inhibitors, respectively. Circular dichroism experiments confirmed that 1 and 5 induced conformational changes to hPTP1B1-400. Further insights into the structure of hPTP1B1-400 were obtained from a homology model, which pointed out that the C-terminus (residues 301-400) is highly disordered. Molecular docking with the homologated model suggested that compounds 1 and 3-5 bind to the C-terminal domain, likely inducing conformational changes on the protein. Docking positions of compounds 1, 4, and 5 were refined with molecular dynamics simulations. Importantly, these simulations confirmed the high flexibility of the C-terminus of hPTP1B1-400, as well as the changes to its rigidity when bound to 1, 4, and 5.


Assuntos
Fenalenos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Talaromyces/química , Simulação por Computador , Dimerização , Humanos , Técnicas In Vitro , Cinética , Simulação de Acoplamento Molecular , Fenalenos/química
17.
Molecules ; 25(8)2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32326502

RESUMO

The aerial parts of Salvia cinnabarina afforded two undescribed labdane diterpenoids 1 and 2 (malonylcommunol and 6ß-hydroxy-trans-communic acid) along with two known labdane diterpenoids, trans-communic acid (3) and trans-communol (4). Additionally, seven known metabolites were also isolated; two isopimarane diterpenoids 5 and 6, two sesquiterpenoids identified as ß-eudesmol (7) and cryptomeridiol (8), and three aromatic compounds identified as phthalic acid (9), a mixture of tyrosol fatty acid esters (10) and the flavone salvigenine (11). While compounds compounds 1-3 showed significant inhibition of yeast α-glucosidase, compounds 2, 3 and 7 had no anti-inflammatory activity in the edema model induced by TPA. This paper is not only the first report on a wild population of Salvia cinnabarina, but also of the presence of labdane-type diterpenoids in a Mexican Salvia sp.


Assuntos
Diterpenos/química , Modelos Moleculares , Estrutura Molecular , Salvia/química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Relação Dose-Resposta a Droga , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Espectroscopia de Ressonância Magnética , Relação Estrutura-Atividade
18.
Planta Med ; 86(13-14): 988-996, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32219776

RESUMO

Recently, the isolation and elucidation of a series of polyhydroxyanthraquinones were reported from an organic extract of a solid phase culture of an endophytic fungus, Penicillium restrictum (strain G85). One of these compounds, ω-hydroxyemodin (1: ), showed promising quorum-sensing inhibition against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) in both in vitro and in vivo models. The initial supply of 1: was 19 mg, and this amount needed to be scaled by a factor of 30 to 50 times, in order to generate material for further in vivo studies. To do so, improvements were implemented to enhance both the fermentation of the fungal culture and the isolation of this compound, with the target of generating > 800 mg of study materials in a period of 13 wk. Valuable insights, both regarding chemistry and mycology, were gained during the targeted production of 1: on the laboratory-scale. In addition, methods were modified to make the process more environmentally friendly by judicious choice of solvents, implementing procedures for solvent recycling, and minimizing the use of halogenated solvents.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Penicillium , Antibacterianos , Fungos , Testes de Sensibilidade Microbiana , Percepção de Quorum
19.
Mol Carcinog ; 59(1): 62-72, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674708

RESUMO

Prostate cancer (PCa) deaths are typically the result of metastatic castration-resistant PCa (mCRPC). Recently, enzalutamide (Enz), an oral androgen receptor inhibitor, was approved for treating patients with mCRPC. Invariably, all PCa patients eventually develop resistance against Enz. Therefore, novel strategies aimed at overcoming Enz resistance are needed to improve the survival of PCa patients. The role of exosomes in drug resistance has not been fully elucidated in PCa. Therefore, we set out to better understand the exosome's role in the mechanism underlying Enz-resistant PCa. Results showed that Enz-resistant PCa cells (C4-2B, CWR-R1, and LNCaP) secreted significantly higher amounts of exosomes (2-4 folds) compared to Enz-sensitive counterparts. Inhibition of exosome biogenesis in resistant cells by GW4869 and dimethyl amiloride strongly decreased their cell viability. Mechanistic studies revealed upregulation of syntaxin 6 as well as its increased colocalization with CD63 in Enz-resistant PCa cells compared to Enz-sensitive cells. Syntaxin 6 knockdown by specific small interfering RNAs in Enz-resistant PCa cells (C4-2B and CWR-R1) resulted in reduced cell number and increased cell death in the presence of Enz. Furthermore, syntaxin 6 knockdown significantly reduced the exosome secretion in both Enz-resistant C4-2B and CWR-R1 cells. The Cancer Genome Atlas analysis showed increased syntaxin 6 expressions associated with higher Gleason score and decreased progression-free survival in PCa patients. Importantly, IHC analysis showed higher syntaxin 6 expression in cancer tissues from Enz-treated patients compared to Enz naïve patients. Overall, syntaxin 6 plays an important role in the secretion of exosomes and increased survival of Enz-resistant PCa cells.


Assuntos
Antineoplásicos/farmacologia , Exossomos/metabolismo , Feniltioidantoína/análogos & derivados , Neoplasias da Próstata/tratamento farmacológico , Proteínas Qa-SNARE/metabolismo , Benzamidas , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Exossomos/efeitos dos fármacos , Humanos , Masculino , Nitrilas , Feniltioidantoína/farmacologia , Neoplasias da Próstata/metabolismo
20.
Front Cell Infect Microbiol ; 10: 597517, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33585272

RESUMO

Blocking virulence is a promising alternative to counteract Pseudomonas aeruginosa infections. In this regard, the phenomenon of cell-cell communication by quorum sensing (QS) is an important anti-virulence target. In this field, fatty acids (FA) have gained notoriety for their role as autoinducers, as well as anti-virulence molecules in vitro, like some saturated FA (SAFA). In this study, we analyzed the anti-virulence activity of SAFA with 12 to18 carbon atoms and compared their effect with the putative autoinducer cis-2-decenoic acid (CDA). The effect of SAFA on six QS-regulated virulence factors and on the secretion of the exoenzyme ExoU was evaluated. In addition, a murine cutaneous infection model was used to determine their influence on the establishment and damage caused by P. aeruginosa PA14. Dodecanoic (lauric, C12:0) and tetradecanoic (myristic, C14:0) acids (SAFA C12-14) reduced the production of pyocyanin by 35-58% at 40 and 1,000 µM, while CDA inhibited it 62% at a 3.1 µM concentration. Moreover, the SAFA C12-14 reduced swarming by 90% without affecting biofilm formation. In contrast, CDA reduced the biofilm by 57% at 3 µM but did not affect swarming. Furthermore, lauric and myristic acids abolished ExoU secretion at 100 and 50 µM respectively, while CDA reduced it by ≈ 92% at 100 µM. Remarkably, the coadministration of myristic acid (200 and 1,000 µM) with P. aeruginosa PA14 induced greater damage and reduced survival of the animals up to 50%, whereas CDA to 500 µM reduced the damage without affecting the viability of the PA14 strain. Hence, our results show that SAFA C12-14 and CDA have a role in regulation of P. aeruginosa virulence, although their inhibition/activation molecular mechanisms are different in complex environments such as in vivo systems.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Animais , Antibacterianos/farmacologia , Biofilmes , Camundongos , Ácidos Mirísticos/farmacologia , Percepção de Quorum , Virulência , Fatores de Virulência/farmacologia
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