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1.
Proc Natl Acad Sci U S A ; 120(34): e2211281120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37579175

RESUMO

Autophagy serves as a defense mechanism against intracellular pathogens, but several microorganisms exploit it for their own benefit. Accordingly, certain herpesviruses include autophagic membranes into their infectious virus particles. In this study, we analyzed the composition of purified virions of the Epstein-Barr virus (EBV), a common oncogenic γ-herpesvirus. In these, we found several components of the autophagy machinery, including membrane-associated LC3B-II, and numerous viral proteins, such as the capsid assembly proteins BVRF2 and BdRF1. Additionally, we showed that BVRF2 and BdRF1 interact with LC3B-II via their common protein domain. Using an EBV mutant, we identified BVRF2 as essential to assemble mature capsids and produce infectious EBV. However, BdRF1 was sufficient for the release of noninfectious viral envelopes as long as autophagy was not compromised. These data suggest that BVRF2 and BdRF1 are not only important for capsid assembly but together with the LC3B conjugation complex of ATG5-ATG12-ATG15L1 are also critical for EBV envelope release.


Assuntos
Capsídeo , Infecções por Vírus Epstein-Barr , Humanos , Capsídeo/metabolismo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Envelope Viral/metabolismo , Infecções por Vírus Epstein-Barr/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo
2.
Nucleic Acids Res ; 50(16): 9368-9381, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36018806

RESUMO

Pseudouridine (Ψ) at position 55 in tRNAs plays an important role in their structure and function. This modification is catalyzed by TruB/Pus4/Cbf5 family of pseudouridine synthases in bacteria and yeast. However, the mechanism of TRUB family underlying the formation of Ψ55 in the mammalian tRNAs is largely unknown. In this report, the CMC/reverse transcription assays demonstrated the presence of Ψ55 in the human mitochondrial tRNAAsn, tRNAGln, tRNAGlu, tRNAPro, tRNAMet, tRNALeu(UUR) and tRNASer(UCN). TRUB1 knockout (KO) cell lines generated by CRISPR/Cas9 technology exhibited the loss of Ψ55 modification in mitochondrial tRNAAsn, tRNAGln, tRNAGlu and tRNAPro but did not affect other 18 mitochondrial tRNAs. An in vitro assay revealed that recombinant TRUB1 protein can catalyze the efficient formation of Ψ55 in tRNAAsn and tRNAGln, but not in tRNAMet and tRNAArg. Notably, the overexpression of TRUB1 cDNA reversed the deficient Ψ55 modifications in these tRNAs in TRUB1KO HeLa cells. TRUB1 deficiency affected the base-pairing (18A/G-Ψ55), conformation and stability but not aminoacylation capacity of these tRNAs. Furthermore, TRUB1 deficiency impacted mitochondrial translation and biogenesis of oxidative phosphorylation system. Our findings demonstrated that human TRUB1 is a highly conserved mitochondrial pseudouridine synthase responsible for the Ψ55 modification in the mitochondrial tRNAAsn, tRNAGln, tRNAGlu and tRNAPro.


Assuntos
Transferases Intramoleculares , RNA de Transferência de Ácido Glutâmico , Animais , Humanos , RNA de Transferência de Glutamina , RNA de Transferência de Prolina , RNA de Transferência de Asparagina , RNA de Transferência de Metionina , Células HeLa , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Pseudouridina/genética , Pseudouridina/metabolismo , RNA de Transferência/metabolismo , Mamíferos/genética
3.
Bioorg Med Chem Lett ; 80: 129081, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36414176

RESUMO

Peroxisome proliferator-activated receptor γ (PPAR γ) antagonists are a key instrument of insulin sensitizers since they have the ability to sensitize insulin and can avoid adverse reactions caused by receptor agonist. In this paper, two series of 28 novel Cajanonic acid A (CAA) derivatives were designed and synthesized. The biological activity showed that a novel CAA derivative 9f was identified as a potential PPAR γ antagonist by medicinal chemistry efforts. The results in vitro displayed that compound 9f could improve the PPAR γ antagonist activity (96.2 % / 50.2 % decrease in PPAR γ transactivation at 10 µM / 1 µM, respectively). It also could improve the glucose consumption activity of insulin-resistant HepG2/3T3-L1 cell line (33.27 % / 72.61 % increase in glucose consumption). And in 3 T3-L1 adipocytes, it showed anti-adipogenesis activity (7.04 % increase in oil red staining). Further, in vivo study suggested that compound 9f could improve the oral glucose tolerance in db/db mice. Taken together, derivative 9f served as a promising candidate for anti-diabetic drug discovery and deserve further study.


Assuntos
Hipoglicemiantes , PPAR gama , Camundongos , Animais , Humanos , PPAR gama/metabolismo , Hipoglicemiantes/farmacologia , Insulina , Glucose/metabolismo , Células Hep G2 , Células 3T3-L1
4.
Org Biomol Chem ; 20(32): 6423-6431, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35880643

RESUMO

An efficient radical annulation of N-arylacrylamides with disulfides is developed for the synthesis of sulfurated oxindoles. The reaction occurs in a facile manner using CoBr2 as both an initiator and a promoter for the first time and (NH4)2S2O8 as the oxidant. By controlling the CoBr2/(NH4)2S2O8 ratio, a wide range of sulfurated and brominated/sulfurated oxindoles are selectively prepared in good to excellent yields. The present protocol is simple and highly atom economical, and can tolerate a broad range of substrates.


Assuntos
Cobalto , Dissulfetos , Indóis , Oxindóis
5.
BMC Cardiovasc Disord ; 22(1): 9, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-35016632

RESUMO

BACKGROUND: Aortic stiffness and coronary heart disease (CHD) share a similar spectrum of risk factors; previous studies have identified the association between aortic stiffness and CHD. Recent studies have demonstrated estimated pulse wave velocity (ePWV) as a simple and easy-acquired indicator of aortic stiffness. Our work aims to evaluate the association between ePWV and the prevalence of CHD and assess the value of ePWV for the identification of prevalent CHD. METHODS: The current cross-sectional work included 7012 subjects from rural areas of southeastern China between September 2020 and February 2021. ePWV was calculated from age and mean blood pressure by specific algorithm. RESULTS: The prevalence of CHD in our population was 3.58% (251 patients among 7012 subjects). After adjusting for age, sex, education, income and exercise level, current smoking and drinking status, body mass index, waist circumference, fasting plasma glucose, total cholesterol, high density lipoprotein, estimated glomerular filtration rate and cerebrovascular diseases, each standard deviation increment of ePWV would produce an additional 37.8% risk of prevalent CHD. Moreover, after dividing ePWV into quartiles, the 4th quartile of ePWV showed a significant risk of prevalent CHD (OR (95% CI): 3.567 (1.963-6.479)) when compared with the 1st quartile. Additionally, the subgroup analysis showed the association between ePWV and prevalent CHD was robust to several common risk factors of CHD, including age, sex, body mass index, hypertension, diabetes and reduced estimated glomerular filtration rate. Finally, the area under curve (AUC) displayed an improvement when adding ePWV into common CHD risk factors (0.705 vs. 0.718. P = 0.044). Consistently, net reclassification index (0.436, 95% CI: 0.301-0.571, P < 0.001) and integrated discrimination index (0.004, 95% CI: 0.001-0.006, P = 0.002) demonstrated the value of ePWV to optimize the identification of prevalent CHD in the general population. CONCLUSION: The present analysis implicates the robust association between ePWV, a simple, rapid, and practical marker of aortic stiffness, and prevalent CHD in the general Chinese population. More importantly, the results suggest the value of ePWV as a potential marker to improve the identification of prevalent CHD.


Assuntos
Pressão Sanguínea/fisiologia , Doença das Coronárias/epidemiologia , Análise de Onda de Pulso/métodos , População Rural , Rigidez Vascular/fisiologia , China/epidemiologia , Doença das Coronárias/diagnóstico , Doença das Coronárias/fisiopatologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reprodutibilidade dos Testes , Fatores de Risco
6.
J Org Chem ; 86(13): 8620-8629, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34097828

RESUMO

An efficient aerobic iron-catalyzed annulation of unsaturated carboxylic acids with disulfides has been developed. This procedure proceeds using FeCl3 as the catalyst and KI as an iodine source under an air atmosphere, which provides practical access to a wide range of substituted γ-lactone derivatives. The disclosed method is quite simple, highly atom-economic, environmentally friendly, and tolerates a broad substrate scope.


Assuntos
Ferro , Lactonas , Ácidos Carboxílicos , Catálise , Dissulfetos
7.
Bioorg Med Chem Lett ; 52: 128410, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34626784

RESUMO

Four series of cajanonic acid A (CAA) derivatives have been designed and synthesized. The newly prepared compounds have been screened for glucose consumption activity in HepG2 cell lines and PPARγ antagonistic activity in HEK293 cell lines. Compound 26g bearing a tetrahydroisoquinolinone scaffold showed the most potent PPARγ antagonistic and hypoglycemic activities. An oral glucose tolerance test (OGTT) was performed and the results further confirmed that 26g was a potent hypoglycemic agent. In addition, the possible binding modes for compound 26g in the PPARγ protein have been investigated in this study.


Assuntos
PPAR gama/antagonistas & inibidores , Extratos Vegetais/farmacologia , Estilbenos/farmacologia , Cajanus/química , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , PPAR gama/metabolismo , Extratos Vegetais/síntese química , Extratos Vegetais/química , Estilbenos/síntese química , Estilbenos/química , Relação Estrutura-Atividade
8.
Chem Soc Rev ; 49(12): 3806-3833, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32478786

RESUMO

With the impetus to accelerate worldwide market adoption of electrical vehicles and afford consumer electronics with better user experience, advancing fast-charging technology is an inevitable trend. However, current high-energy lithium-ion batteries are unable to support ultrafast power input without any adverse consequences, with the capacity fade and safety concerns of the mainstream graphite-based anodes being the key technological barrier. The aim of this review is to summarise the fundamentals, challenges, and solutions to enable graphite anodes that are capable of high-rate charging. First, we explore the complicated yet intriguing graphite-electrolyte interface during intercalation based on existing theories. Second, we analyse the key dilemmas facing fast-charging graphite anodes. Finally, some promising strategies proposed during the past few years are highlighted so as to outline current trends and future perspectives in this field.

9.
J Cell Physiol ; 234(12): 23315-23325, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31140610

RESUMO

MicroRNAs (miRNAs) is a small molecule (19-25 nucleotide) noncoding RNA that inhibits the expression of target messenger RNA (mRNA) at the posttranscriptional level as an endogenous regulator. There is an increasing evidence that miR-199a-3p has a significant effect on the development of multiple tumors. However, the specific roles of miR-199a-3p in myocardial differentiation of embryonic stem cell still need to be investigated. Method of the hanging drop was used to build the model of cardiomyocyte differentiation of stem cell and beating rate of embryoid bodies (EBs) was calculated. The levels of intracellular MEF2C, a-MHC, GATA4, Nkx2.5, and cTnT mRNA were measured by real-time quantitative polymerase chain reaction, while the expressions of miR-199a-3p were detected simultaneously. Protein levels of MEF2C, a-MHC, GATA4, Nkx2.5, and cTnT were quantified by western blot analysis. Immunoreactivities of MEF2C and cTnT were analyzed by immunofluorescence. The interaction between miR-199a-3p and its predicted target (3'-untranslated region of MEF2C mRNA) was verified by luciferase assay. MiR-199a-3p levels increased during cardiogenesis. MiR-199a-3p inhibitor increased the beating rate of EBs and promoted expressions of cardiac-specific markers (GATA4, Nkx2.5, cTnT, and a-MHC). Notably, miR-199a-3p inhibition brought upregulation of MEF2C, which is the target of miR-199a-3p that we predicted and verified experimentally. In addition, MEF2C siRNA decreased miR-199a-3p inhibitor promoted EBs beating and attenuated miR-199a-3p inhibitor-induced cTnT and MEF2C expressions. The results above showed that MEF2C was involved in the process of promoting the differentiation of stem cells into cardiac myocytes by miR-199a-3p inhibitors.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/metabolismo , MicroRNAs/metabolismo , Miócitos Cardíacos/metabolismo , Linhagem Celular , Células-Tronco Embrionárias/citologia , Regulação da Expressão Gênica/fisiologia , Humanos , Fatores de Transcrição MEF2/metabolismo , Miócitos Cardíacos/citologia
10.
Small ; 15(15): e1805389, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30869836

RESUMO

Fast charging enables electronic devices to be charged in a very short time, which is essential for next-generation energy storage systems. However, the increase of safety risks and low coulombic efficiency resulting from fast charging severely hamper the practical applications of this technology. This Review summarizes the challenges and recent progress of lithium batteries for fast charging. First, it describes the definition of fast charging and proposes a critical value of ionic and electrical conductivity of electrodes for fast charging in a working battery. Then based on this definition, the requirements and optimization strategies of the electrode, electrolyte, and electrode/electrolyte interface for fast charging are proposed. Finally, a general conclusion and perspectives on the better understanding of lithium batteries with fast charging capability are presented.

11.
Acta Paediatr ; 2018 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-29569350

RESUMO

AIM: We evaluated how effectively the waist-to-height ratio (WHtR) identified cardiometabolic risk (CMR) in children and adolescents, compared with the tri-ponderal mass index, percentage of body fat and other obesity indexes. METHODS: Eligible subjects were recruited from three metropolitan regions of China from May 2013 to June 2014. Subjects with at least three of the following abnormalities - hypertension, dyslipidemia, elevated fasting blood glucose and central obesity - were defined as CMR1 and children with at least two were defined as CMR2. The area under the curve (AUC) of the receiver operating characteristic curve was used to compare how effectively obesity indexes predicted CMR. RESULTS: We recruited 3556 subjects aged 7-18 years. All five obesity indexes showed good, comparable performances in identifying CMR and the AUCs ranged from 0.89 to 0.90 for CMR1 and 0.83 to 0.85 for CMR2. The cut-off of 0.467 for WHtR achieved a sensitivity of 0.91 and specificity of 0.80 for predicting CMR1, with the best cut-offs being 0.463 for boys and 0.469 for girls. CONCLUSION: The WHtR was a superior and practical screening tool for detecting CMR in this paediatric population, as it provided comparable accuracy to other methods and just required a simple calculation.

12.
BMC Neurosci ; 18(1): 32, 2017 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-28288585

RESUMO

BACKGROUND: Ischemic stroke is a major disease that threatens human health in ageing population. Increasing evidence has shown that neuroinflammatory mediators play crucial roles in the pathophysiology of cerebral ischemia injury. Notch signaling is recognized as the cell fate signaling but recent evidence indicates that it may be involved in the inflammatory response in activated microglia in cerebral ischemia. Previous report in our group demonstrated hypertonic saline (HS) could reduce the release of interleukin-1 beta and tumor necrosis factor-alpha in activated microglia, but the underlying molecular and cellular mechanisms have remained uncertain. This study was aimed to explore whether HS would partake in regulating production of proinflammatory mediators through Notch signaling. RESULTS: HS markedly attenuated the expression of Notch-1, NICD, RBP-JK and Hes-1 in activated microglia both in vivo and in vitro. Remarkably, HS also reduced the expression of iNOS in vivo, while the in vitro levels of inflammatory mediators Phos-NF-κB, iNOS and ROS were reduced by HS as well. CONCLUSION: Our results suggest that HS may suppress of inflammatory mediators following ischemia/hypoxic through the Notch signaling which operates synergistically with NF-κB pathway in activated microglia. Our study has provided the morphological and biochemical evidence that HS can attenuate inflammation reaction and can be neuroprotective in cerebral ischemia, thus supporting the use of hypertonic saline by clinicians in patients with an ischemia stroke.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Hipóxia Celular/efeitos dos fármacos , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Receptores Notch/metabolismo , Solução Salina Hipertônica/farmacologia , Animais , Isquemia Encefálica/imunologia , Isquemia Encefálica/patologia , Hipóxia Celular/fisiologia , Linhagem Celular , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Masculino , Camundongos , Microglia/imunologia , Microglia/patologia , Óxido Nítrico Sintase Tipo II/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/patologia , Transdução de Sinais/efeitos dos fármacos
13.
Bioorg Med Chem Lett ; 27(8): 1750-1753, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28285912

RESUMO

In an effort to discover potent camptothecin-derived antitumor agents, novel camptothecin analogues with sulfonylpiperazinyl motifs at position-7 were designed and synthesized. They were evaluated for in vitro cytotoxicity with the sulforhodamine-B (SRB) method in five types of human tumor cell lines, A-549, MDA-MB-231, KB, KB-VIN and MCF-7. With IC50 values in the low µM to nM level, most of the new analogues showed greater cytotoxicity activity than the reference compounds irinotecan and topotecan. Furthermore, compounds 12l (IC50, 1.2nM) and 12k (IC50, 20.2nM) displayed the highest cytotoxicity against the multidrug-resistant (MDR) KB-VIN cell line and merit further development as preclinical drug candidates for treating cancer, including MDR phenotype. Our study suggested that integration of sulfonylpiperazinyl motifs into position-7 of camptothecin is an effective strategy for discovering new potent cytotoxic camptothecin derivatives.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Camptotecina/análogos & derivados , Camptotecina/farmacologia , Piperazinas/química , Piperazinas/farmacologia , Antineoplásicos/síntese química , Camptotecina/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Metilação , Neoplasias/tratamento farmacológico , Piperazina , Piperazinas/síntese química , Sulfonas/síntese química , Sulfonas/química , Sulfonas/farmacologia
14.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(5): 534-538, 2017 May.
Artigo em Zh | MEDLINE | ID: mdl-28506344

RESUMO

OBJECTIVE: To investigate PHEX gene mutations in 2 patients with X-linked hypophosphatemic rickets (XLH) and their families and to clarify the genetic etiology. METHODS: A retrospective analysis was performed for the clinical data of two patients with XLH. High-throughput sequencing was used to detect the PHEX gene, a pathogenic gene of XLH. PCR-Sanger sequencing was used to verify the distribution of mutations in families. RESULTS: Both patients had novel mutations in the PHEX gene; one patient had a frameshift mutation, c.931dupC, which caused early termination of translation and produced the truncated protein p.Gln311Profs*13; the other patient had a splice site mutation, IVS14+1G>A, which caused the skipping of exon 15 and produced an incomplete amino acid chain. Their parents had normal gene phenotypes. CONCLUSIONS: c.931dupC and IVS14+1G>A are two novel mutations of the PHEX gene and might be the new pathogenic mutations of XLH.


Assuntos
Raquitismo Hipofosfatêmico Familiar/genética , Mutação , Endopeptidase Neutra Reguladora de Fosfato PHEX/genética , Criança , Pré-Escolar , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Estudos Retrospectivos
15.
Zhong Yao Cai ; 39(7): 1477-82, 2016 Jul.
Artigo em Zh | MEDLINE | ID: mdl-30203942

RESUMO

Objective: To analyze ITS region and matK gene sequences of three medicinal Phlomis plants,in order to provide molecular basis for identifying and protecting their wild resources. Methods: PCR and sequencing were conducted on Phlomis likiangensis,Phlomis melanantha and Phlomis betonicoides wild populations by primers pairs ITS4 / ITS5 and matKXF / matK5 R. Results: The smallest inter-K2 P genetic distance was further than the largest intra-K2 P genetic distance in Phlomis likiangensis, Phlomis melanantha and Phlomis betonicoides. Different samples of three medicinal Phlomis plants were gathered together and could be distinguished from other exogenous species by Neighbor-Joining( NJ) tree. Phlomis likiangensis, Phlomis melanantha and Phlomis betonicoides had three, three and one sites on ITS2 for their effective identification, and had three,three and three sites on ITS1 for their effective identification respectively. Phlomis betonicoides had three sites on matK for its effective identification, while Phlomis likiangensis or Phlomis melanantha needed multiple sites for their effective identification. Conclusion: The study implies that ITS1,ITS2 and matK fragments could be used for molecular identification of Phlomis likiangensis, Phlomis melanantha and Phlomis betonicoides.


Assuntos
Código de Barras de DNA Taxonômico , Phlomis , China , DNA de Plantas , Plantas Medicinais , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas pp60(c-src)
16.
Med Res Rev ; 35(4): 753-89, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25808858

RESUMO

Camptothecins (CPTs) are cytotoxic natural alkaloids that specifically target DNA topoisomerase I. Research on CPTs has undergone a significant evolution from the initial discovery of CPT in the late 1960s through the study of synthetic small-molecule derivatives to investigation of macromolecular constructs and formulations. Over the past years, intensive medicinal chemistry efforts have generated numerous CPT derivatives. Three derivatives, topotecan, irinotecan, and belotecan, are currently prescribed as anticancer drugs, and several related compounds are now in clinical trials. Interest in other biological effects, besides anticancer activity, of CPTs is also growing exponentially, as indicated by the large number of publications on the subject during the last decades. Therefore, the main focus of the present review is to provide an ample but condensed overview on various biological activities of CPT derivatives, in addition to continued up-to-date coverage of anticancer effects.


Assuntos
Camptotecina/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Camptotecina/química , Humanos
17.
Bioorg Med Chem Lett ; 25(13): 2690-3, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25987370

RESUMO

In our continuing search for camptothecin (CPT)-derived antitumor drugs, novel structurally diverse PEG-based 20(S)-CPT sulfonylamidine derivatives were designed, synthesized via a Cu-multicomponent reaction (MCR), and evaluated for cytotoxicity against four human tumor cell lines (A-549, MDA-MB-231, KB, and KBvin). All of the derivatives showed promising in vitro cytotoxic activity against the tested tumor cell lines, and were more potent than irinotecan. Significantly, these derivatives exhibited comparable cytotoxicity against KBvin, while irinotecan was less active against this cell line. With a concise efficient synthesis and potent cytotoxic profiles, especially significant activity towards KBvin, these compounds merit further development as a new generation of CPT-derived PEG-conjugated drug candidates.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Camptotecina/análogos & derivados , Antineoplásicos/química , Camptotecina/síntese química , Camptotecina/química , Camptotecina/farmacologia , Catálise , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cobre , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Irinotecano , Células KB , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Relação Estrutura-Atividade
18.
Molecules ; 20(5): 8634-53, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25985362

RESUMO

In continuation of our program aimed at the development of natural product-based pesticidal agents, three series of novel camptothecin derivatives were designed, synthesized, and evaluated for their biological activities against T. Cinnabarinus, B. brassicae, and B. xylophilus. All of the derivatives showed good-to-excellent activity against three insect species tested, with LC50 values ranging from 0.00761 to 0.35496 mmol/L. Remarkably, all of the compounds were more potent than CPT against T. Cinnabarinus, and compounds 4d and 4c displayed superior activity (LC50 0.00761 mmol/L and 0.00942 mmol/L, respectively) compared with CPT (LC50 0.19719 mmol/L) against T. Cinnabarinus. Based on the observed bioactivities, preliminary structure-activity relationship (SAR) correlations were also discussed. Furthermore, a three-dimensional quantitative structure-activity relationship (3D-QSAR) model using comparative molecular field analysis (CoMFA) was built. The model gave statistically significant results with the cross-validated q2 values of 0.580 and correlation coefficient r2 of 0.991 and  of 0.993. The QSAR analysis indicated that the size of the substituents play an important in the activity of 7-modified camptothecin derivatives. These findings will pave the way for further design, structural optimization, and development of camptothecin-derived compounds as pesticidal agents.


Assuntos
Agentes de Controle Biológico/química , Camptotecina/análogos & derivados , Camptotecina/química , Inseticidas/química , Animais , Afídeos/efeitos dos fármacos , Nematoides/efeitos dos fármacos , Relação Quantitativa Estrutura-Atividade , Tetranychidae/efeitos dos fármacos
19.
Cell Physiol Biochem ; 34(4): 1318-38, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25301359

RESUMO

BACKGROUND/AIMS: Liver is a vital organ and retains its regeneration capability throughout adulthood, which requires contributions from different cell populations, including liver precursors and intrahepatic stem cells. To overcome the mortality of hepatic progenitors (iHPs) in vitro, we aim to establish reversibly immortalized hepatic progenitor cells from mouse embryonic liver. METHODS AND RESULTS: Using retroviral system to stably express SV40 T antigen flanked with Cre/LoxP sites, we establish a repertoire of iHP clones with varied differentiation potential. The iHP cells maintain long-term proliferative activity and express varied levels of progenitor markers (Pou5f1/Oct4 and Dlk) and hepatocyte markers (AFP, Alb and ApoB). Five representative iHP clones express hepatic/pancreatic transcription factors HNF3α/Foxa1, HNF3ß/Foxa2, and HNF4α/MODY1. Dexamethasone is shown to promote the expression of hepatocyte markers AFP and TAT, along with ICG-uptake and glycogen storage functions in the iHP clones. Cre-mediated removal of SV40 T antigen reverses the proliferative activity of iHP cells. When iHP cells are subcutaneously implanted in athymic nude mice, no tumor formation is observed for up to 8 weeks. CONCLUSIONS: We demonstrate that the established iHP cells are stable, reversible, and non-tumorigenic hepatic progenitor-like cells, which should be valuable for studying liver organogenesis, metabolic regulations, and hepatic lineage-specific differentiation.


Assuntos
Células-Tronco Embrionárias/fisiologia , Hepatócitos/fisiologia , Fígado/fisiologia , Células-Tronco/citologia , Animais , Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular , Proliferação de Células/fisiologia , Células-Tronco Embrionárias/metabolismo , Feminino , Glicogênio/metabolismo , Células HEK293 , Humanos , Fígado/metabolismo , Camundongos , Camundongos Nus , Células-Tronco/metabolismo
20.
J Neuroinflammation ; 11: 102, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24916922

RESUMO

BACKGROUND: Hypertonic saline (HS) has been successfully used clinically for treatment of various forms of cerebral edema. Up-regulated expression of Na-K-Cl Cotransporter 1 (NKCC1) and inflammatory mediators such as tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1ß) has been demonstrated to be closely associated with the pathogenesis of cerebral edema resulting from a variety of brain injuries. This study aimed to explore if alleviation of cerebral edema by 10% HS might be effected through down-regulation of inflammatory mediator expression in the microglia, and thus result in decreased NKCC1 expression in astrocytes in the cerebral cortex bordering the ischemic core. METHODS: The Sprague-Dawley (SD) rats that underwent right-sided middle cerebral artery occlusion (MCAO) were used for assessment of NKCC1, TNF-α and IL-1ß expression using Western blotting, double immunofluorescence and real time RT-PCR, and the model also was used for evaluation of brain water content (BWC) and infarct size. SB203580 and SP600125, specific inhibitors of the p38 and JNK signaling pathways, were used to treat primary microglia cultures to determine whether the two signaling pathways were required for the inhibition of HS on microglia expressing and secreting TNF-α and IL-1ß using Western blotting, double immunofluorescence and enzyme-linked immunosorbent assay (ELISA). The effect of TNF-α and IL-1ß on NKCC1 expression in primary astrocyte cultures was determined. In addition, the direct inhibitory effect of HS on NKCC1 expression in primary astrocytes was also investigated by Western blotting, double immunofluorescence and real time RT-PCR. RESULTS: BWC and infarct size decreased significantly after 10% HS treatment. TNF-α and IL-1ß immunoexpression in microglia was noticeably decreased. Concomitantly, NKCC1 expression in astrocytes was down-regulated. TNF-α and IL-1ß released from the primary microglia subjected to hypoxic exposure and treatment with 100 mM HS were decreased. NKCC1 expression in primary astrocytes was concurrently and progressively down-regulated with decreasing concentration of exogenous TNF-α and IL-1ß. Additionally, 100 mM HS directly inhibited NKCC1 up-regulation in astrocytes under hypoxic condition. CONCLUSIONS: The results suggest that 10% HS alleviates cerebral edema through inhibition of the NKCC1 Cotransporter, which is mediated by attenuation of TNF-α and IL-1ß stimulation on NKCC1.


Assuntos
Edema Encefálico/tratamento farmacológico , Citocinas/metabolismo , Microglia/efeitos dos fármacos , Solução Salina Hipertônica/uso terapêutico , Membro 2 da Família 12 de Carreador de Soluto/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Edema Encefálico/etiologia , Edema Encefálico/patologia , Células Cultivadas , Modelos Animais de Doenças , Lateralidade Funcional , Proteína Glial Fibrilar Ácida/metabolismo , Infarto da Artéria Cerebral Média/complicações , Interleucina-1beta/metabolismo , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Membro 2 da Família 12 de Carreador de Soluto/genética , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo
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