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1.
Pestic Biochem Physiol ; 199: 105771, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458679

RESUMO

Among the six-membered heterocycles, the pyrazine ring is poorly explored in crop protection and does not feature in any product listed in the current IRAC MoA classification. In an effort to identify new leads for internal research, we synthesized a series of N-(5-phenylpyrazin-2-yl)-benzamide derivatives and evaluated them for their insecticidal activity. N-(5-phenylpyrazin-2-yl)-benzamide derivatives 3 were prepared using an automated two-step synthesis protocol. These compounds were tested for their initial biological activity against a wide range of sucking and chewing insect pests and found to be active against lepidopterans only. More detailed experiments, including symptomology studies on the diamondback moth, Plutella xylostella (L.) and the Egyptian cotton leafworm, Spodoptera littoralis (Boisduval) showed that analog 3q causes severe abnormalities in the lepidopteran cuticle leading to larval mortality. Compound 3q shows strong potency against both P. xylostella and S. littoralis, whereas analog 3i shows better potency against S. littoralis causing also impaired cuticular structure and death of the larvae. Additionally, P. xylostella genetic studies showed that compound 3q resistance is linked to Chitin Synthase 1. Our studies show that N-(5-phenylpyrazin-2-yl)-benzamide derivatives 3, and in particular analogs 3i and 3q, act as insect growth modulator insecticides. Conformational similarities with lufenuron are discussed.


Assuntos
Inseticidas , Mariposas , Animais , Inseticidas/farmacologia , Mariposas/genética , Larva , Insetos , Spodoptera , Quitina
2.
Mycopathologia ; 189(1): 16, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38324097

RESUMO

Invasive candidiasis (IC), caused by Candida yeasts, particularly Candida albicans, poses a significant threat with high mortality rates. Diagnosis is challenging due to Candida's common presence in human microbiota. To address this, our research group developed an immunofluorescence assay detecting Candida albicans Germ Tube Antibodies (CAGTA) in IC patients. CAGTA, indicative of invasive processes, is associated with a lower mortality rate in ICU patients. Based on this premise, this study aims to provide results regarding the lack of knowledge about the potential activity of CAGTA against invasive infections in humans caused by the fungus Candida albicans. Therefore, in order to characterize the activity of CAGTA produced by patients with IC, we used sera from 29 patients with IC caused by either C. albicans or non-albicans Candida species. Whole serum IgG antibodies were fractionated into anti-blastospores, CAGTA-enriched, and purified CAGTA and the assessments included XTT colorimetric assays for metabolic activity, CFU counts for viability, and microscopy for growth, viability, and morphological analysis. The CAGTA-enriched IgG fraction significantly reduced the metabolic activity and viability of C. albicans compared to anti-blastospores. Purified CAGTA altered germ tube cell wall surfaces, as revealed by electron microscopy, and exhibited fungicidal properties by DiBAC fluorescent staining. In conclusion, antibodies in response to invasive candidiasis have antifungal activity against Candida albicans, influencing metabolic activity, viability, and cell wall structure, leading to cell death. These findings suggest the potential utility of CAGTA as diagnostic markers and support the possibility of developing immunization protocols against Candida infections.


Assuntos
Candida albicans , Candidíase Invasiva , Candidíase , Humanos , Candida , Parede Celular , Anticorpos Antifúngicos , Imunoglobulina G
3.
Turk J Med Sci ; 54(1): 26-32, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812622

RESUMO

Background/aim: To investigate the roles of vascular endothelial growth inhibitor (VEGI) and hypoxia-inducible factor-1α (HIF-1α) in the treatment of refractory interstitial cystitis/bladder pain syndrome (IC/BPS) with hyperbaric oxygen (HBO). Materials and methods: A total of 38 patients were included. They were assessed before and 6 months after HBO treatment. Three-day voiding diaries were recorded, and O'leary-Sant scores, visual analog scale (VAS) scores, quality of life (QoL) scores, pelvic pain, and urgency/frequency (PUF) scores were evaluated. Bladder capacity was assessed by cystoscopy. Bladder mucosa was collected for Western blot, qRT-PCR, and immunofluorescence staining to compare the expression of VEGI and HIF-1α before and after treatment. Results: Compared with before treatment, patients showed significant improvements in 24-h voiding frequency (15.32 ± 5.38 times), nocturia (3.71 ± 1.80 times), O'leary-Sant score (20.45 ± 5.62 points), VAS score (41.76 ± 17.88 points), QoL score (3.03 ± 1.44 points), and PUF score (19.95 ± 6.46 points) after treatment (p < 0.05). There was no significant difference in bladder capacity before and after treatment (p ≥ 0.05). The expression levels of VEGI and HIF-1α protein and mRNA were significantly decreased 6 months after treatment compared with before treatment. Immunofluorescence staining results showed that the double positive expression of VEGI and HIF-1α protein in bladder tissue of IC/BPS patients after HBO treatment quantitatively decreased significantly. Conclusion: This study identified a possible mechanism by which VEGI and HIF-1α expression decreased after HBO treatment due to hypoxia reversal, which improved symptoms in IC/BPS patients.


Assuntos
Cistite Intersticial , Oxigenoterapia Hiperbárica , Subunidade alfa do Fator 1 Induzível por Hipóxia , Humanos , Oxigenoterapia Hiperbárica/métodos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Feminino , Pessoa de Meia-Idade , Masculino , Cistite Intersticial/terapia , Cistite Intersticial/metabolismo , Adulto , Qualidade de Vida , Bexiga Urinária/metabolismo , Idoso , Resultado do Tratamento
4.
Angew Chem Int Ed Engl ; 63(2): e202314457, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38010613

RESUMO

Single crystallization of LiNix Coy Mn1-x-y O2 (NCM) is currently an effective strategy to improve the cycling life of NCM cathode, owing to the reduced surface area and enhanced mechanical strength, but the application of single crystal NCM(SC-NCM) is being hindered by severe particle agglomeration and poor C-rate performance. Here, a strategy of three-section-sintering(TSS) with the presence of grain-growth inhibitor was proposed, in which, the TSS includes three sections of phase-formation, grain-growth and phase-preservation. While, the addition of MoO3 inhibits the grain growth and restrains the particle agglomeration. With the help of TSS and 1 mol % of MoO3 , highly dispersed surface Mo-doped SC-NCM(MSC-NCM) cubes are obtained with the average diameter of 1.3 µm. Benefiting from the surface Mo-doping and the reduced surface energy, the Li+ -migration preferred (1 0 4) crystalline facet is exposed as the dominant plane in MSC-NCM cubes, because of which, C-rate performance is significantly improved compared with the regular SC-NCM. Furthermore, this preparation strategy is compatible well with the current industrial production line, providing an easy way for the large-scale production of SC-NCM.

5.
Anim Biotechnol ; 34(7): 2999-3007, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36170026

RESUMO

Mammary-derived growth inhibitor (MDGI), a member of the lipophilic family of fatty acid-binding proteins, plays an important role in the development, regulation, and differentiation of the mammary gland. The aim of the study was to identify polymorphism in the MDGI gene and its expression analysis in the mammary gland at various stages of lactation, in Indian buffalo. Nucleotide sequence analysis of MDGI gene in different breeds of riverine and swamp buffaloes revealed a total of 16 polymorphic sites and one Indel. Different transcription factor binding sites were predicted for buffalo MDGI gene promoter sequence, using online tools and in-silico analysis indicating that the SNPs in this region can impact the gene expression regulation. Phylogenetic analysis exhibited the MDGI of buffalo being closer to other ruminants like cattle, yak, sheep, and goats. Further, the expression analysis revealed that buffalo MDGI being highly expressed in well-developed mammary glands of lactating buffalo as compared to involution/non-lactating and before functional development to start the milk production stage in heifers. Stage-specific variation in expression levels signifies the important functional role of the MDGI gene in mammary gland development and milk production in buffalo, an important dairy species in Southeast Asia.


Assuntos
Búfalos , Lactação , Feminino , Animais , Bovinos , Ovinos , Búfalos/genética , Lactação/genética , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Inibidores do Crescimento/metabolismo , Glândulas Mamárias Animais/metabolismo
6.
Crit Rev Biotechnol ; 42(7): 973-990, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34521281

RESUMO

Although several metal ions/metal nanoparticles (NPs) are toxic to both plants and animals, some of them are used as nutrients and growth promoters. Plants exposed to silver nanoparticles (Ag-NPs) have shown both beneficial and harmful effects. All concentrations of Ag-NPs are not effective for a given plant because any excess can block the passage of essential nutrients. Regulated treatment of plants by Ag-NPs may enhance their overall growth and development. It has been noticed that Ag-NPs decrease the mass of edible plants (Cucurbita pepo, Allium cepa, cabbage, and lettuce) and vegetables, but they also induce the germination of seeds in many cases. NPs interact with proteins, enzymes, and carbohydrates influencing the total biomass, root, and shoot growth of plants. Also, Ag-NPs act as an ethylene inhibitor and activate the antioxidants in onions. Their substantial quantity becomes deposited in onion leaves and bulbs. Size and concentration are the two major factors responsible for the increase/decrease of plant growth and biomass. Plants make adaptations to reduce the toxicity caused by Ag-NPs. In some cases, Ag-NPs induce root elongation and increase chlorophyll, carbohydrate, proteins, rate of photosynthesis and inhibit the biosynthesis of ethylene. This review article provides a comprehensive overview of both the beneficial and adverse effects of Ag-NPs on germination, growth, development, physiological, and biochemical characteristics of a wide range of edible and crop plants. We have also critically discussed: the chemistry, toxicity, uptake, translocation, and accumulation of Ag-NPs in plant systems.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Carboidratos , Clorofila , Etilenos , Íons , Nanopartículas Metálicas/toxicidade , Prata/metabolismo , Prata/toxicidade
7.
Int J Mol Sci ; 23(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35897792

RESUMO

Aedes aegypti is the main vector that transmits viral diseases such as dengue, hemorrhagic dengue, urban yellow fever, zika, and chikungunya. Worldwide, many cases of dengue have been reported in recent years, showing significant growth. The best way to manage diseases transmitted by Aedes aegypti is to control the vector with insecticides, which have already been shown to be toxic to humans; moreover, insects have developed resistance. Thus, the development of new insecticides is considered an emergency. One way to achieve this goal is to apply computational methods based on ligands and target information. In this study, sixteen compounds with acceptable insecticidal activities, with 100% larvicidal activity at low concentrations (2.0 to 0.001 mg·L−1), were selected from the literature. These compounds were used to build up and validate pharmacophore models. Pharmacophore model 6 (AUC = 0.78; BEDROC = 0.6) was used to filter 4793 compounds from the subset of lead-like compounds from the ZINC database; 4142 compounds (dG < 0 kcal/mol) were then aligned to the active site of the juvenile hormone receptor Aedes aegypti (PDB: 5V13), 2240 compounds (LE < −0.40 kcal/mol) were prioritized for molecular docking from the construction of a chitin deacetylase model of Aedes aegypti by the homology modeling of the Bombyx mori species (PDB: 5ZNT), which aligned 1959 compounds (dG < 0 kcal/mol), and 20 compounds (LE < −0.4 kcal/mol) were predicted for pharmacokinetic and toxicological prediction in silico (Preadmet, SwissADMET, and eMolTox programs). Finally, the theoretical routes of compounds M01, M02, M03, M04, and M05 were proposed. Compounds M01−M05 were selected, showing significant differences in pharmacokinetic and toxicological parameters in relation to positive controls and interaction with catalytic residues among key protein sites reported in the literature. For this reason, the molecules investigated here are dual inhibitors of the enzymes chitin synthase and juvenile hormonal protein from insects and humans, characterizing them as potential insecticides against the Aedes aegypti mosquito.


Assuntos
Aedes , Dengue , Inseticidas , Infecção por Zika virus , Zika virus , Animais , Biologia Computacional , Inibidores do Crescimento , Humanos , Insetos , Inseticidas/química , Inseticidas/farmacologia , Larva , Simulação de Acoplamento Molecular , Mosquitos Vetores
8.
Biotechnol Bioeng ; 118(12): 4786-4799, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34569627

RESUMO

Chinese hamster ovary (CHO) cells in fed-batch cultures produce several metabolic byproducts derived from amino acid catabolism, some of which accumulate to growth inhibitory levels. Controlling the accumulation of these byproducts has been shown to significantly enhance cell proliferation. Interestingly, some of these byproducts have physiological roles that go beyond inhibition of cell proliferation. In this study, we show that, in CHO cell fed-batch cultures, branched-chain amino acid (BCAA) catabolism contributes to the formation of butyrate, a novel byproduct that is also a well-established specific productivity enhancer. We further show that other byproducts of BCAA catabolism, namely isovalerate and isobutyrate, which accumulate in CHO cell fed-batch cultures, also enhance specific productivity. Lastly, we show that the rate of production of these BCAA catabolic byproducts is negatively correlated with glucose uptake and lactate production rates. Thus, limiting glucose supply to suppress glucose uptake and lactate production, as in the case of fed-batch cultures employing high-end pH-controlled delivery of glucose (HiPDOG) technology, significantly enhances BCAA catabolic byproduct accumulation, resulting in higher specific productivities.


Assuntos
Aminoácidos de Cadeia Ramificada/metabolismo , Técnicas de Cultura Celular por Lotes/métodos , Butiratos/metabolismo , Aminoácidos de Cadeia Ramificada/análise , Animais , Reatores Biológicos , Butiratos/análise , Células CHO , Cricetinae , Cricetulus , Meios de Cultura/química , Meios de Cultura/metabolismo , Glucose/metabolismo
9.
Biosci Biotechnol Biochem ; 85(7): 1602-1608, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34003212

RESUMO

The use of biopesticides has expanded rapidly in recent years; however, their use in weed control is less advanced. Herein, we describe the development of a weed control agent by screening 208 plant extracts (104 species) for their plant growth-inhibition activities, which resulted in 142 active samples (from 89 plant species). Verbascoside, isolated from the shoots of Verbena incompta, was identified as a growth inhibitor against rice root (EC50, 1.75 m m), and its root growth-inhibition activity was also confirmed in radish, tomato, and Lotus japonicus. Verbascoside is composed of hydroxytyrosol (EC50,12.51 m m) and caffeic acid (EC50, 4.08 m m), 2 poorly water-soluble phenolic components with weak growth-inhibition activities, and 2 sugars, which are more soluble but inactive. The plant apparently developed a more active and highly soluble compound by condensing these 4 components. We conclude that a biopesticide containing verbascoside may be useful for weed-control purposes.


Assuntos
Glucosídeos/farmacologia , Herbicidas/farmacologia , Fenóis/farmacologia , Raízes de Plantas/efeitos dos fármacos , Verbena/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Herbicidas/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação , Raízes de Plantas/crescimento & desenvolvimento , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento , Análise Espectral/métodos
10.
Ecotoxicology ; 30(4): 751-755, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33770306

RESUMO

Regeneration is a widely spread process across the animal kingdom, including many species of marine crustaceans. It is strongly linked to hormonal cycles and, therefore, a great endpoint candidate for toxicology studies. We selected the amphipod Parhyale hawaiensis as test organism, already used in ecotoxicological studies and able to regenerate its body appendages. We are proposing a protocol to use the antenna regeneration as a toxicity endpoint. First, we evaluated differences in time of completion of regeneration in males and females after the amputation of one antenna of 6 months old animals. Then we compared the influence of different testing volumes in the regeneration process (100 and 5 mL). We used as testing substances, dimethyl sulfoxide (DMSO) and diflubenzuron, a chitin synthesis inhibitor. The most suitable protocol consisted of volumes of 5 mL in 12-well microplates, with 1 organism per well, 12 organisms per concentration (1:1 females/males) and test time duration of around 5 weeks. DMSO accelerated regeneration time with a NOEC of 0.06%. Diflubenzuron inhibited the time necessary to its completion with a NOEC of 0.32 µg L-1. We conclude that the Parhyale hawaiensis antenna regeneration protocol proposed here is a potential tool in ecotoxicology, but more studies are required for its validation not only to verify its utility for testing chemicals but also environmental samples.


Assuntos
Anfípodes , Diflubenzuron , Animais , Dimetil Sulfóxido/toxicidade , Ecotoxicologia , Feminino , Masculino
11.
Invest New Drugs ; 38(3): 785-799, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31257554

RESUMO

BackgroundWe investigated the role of reactive oxygen species (ROS) in the anticancer mechanism of N-benzyl-2-nitro-1-imidazole-acetamide (BZN), a drug used in Chagas' disease treatment. MethodsBALB/c mice, inoculated with Ehrlich ascites carcinoma (EAC), were treated with BZN or BZN + Nacylcysteine (NAC) or NAC for 9 days. Subsequently, the inhibition of tumor growth and angiogenesis as well as animal survival were evaluated. Apoptosis and the cell cycle were evaluated using fluorescence microscopy and flow cytometry, while oxidative stress was evaluated by measuring TBARS content, DNA damage, calcium influx and ROS generation and antioxidant defenses (CAT, SOD, GPx, GST and GR). Immunoblotting was used to evaluate key death and cell cycle proteins. Results BZN treatment inhibited tumor progression (79%), angiogenesis (2.8-fold) and increased animal survival (29%). Moreover, BZN increased ROS levels (42%), calcium influx (55%), TBARS contents (1.9-fold), SOD (4.4-fold), GPx (17.5-fold) and GST (3-fold) activities and GSH depletion (2.5-fold) also caused DNA fragmentation (7.6-fold), increased cleaved PARP and promoted the trapping of cells in the G1 phase, as corroborated by the reduction in cyclin A and increased CDK2 protein levels. In silico DNA and molecular dynamic simulations showed H-bonds and hydrophobic interactions that were confirmed by circular dichroism. Increased apoptosis (232%), induced by treatment with BZN, was demonstrated by apoptotic cell staining and p53 level. Conclusion The current findings indicate that BZN acts as a tumor growth inhibitor and anti-angiogenic agent by ROS overgeneration, which interact with DNA causing damage and triggering apoptosis.


Assuntos
Acetamidas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Imidazóis/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos
12.
Chemistry ; 26(67): 15438-15445, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956545

RESUMO

The recently delineated structure- and reactivity-based concept of antivitamins B12 has begun to bear fruit by the generation, and study, of a range of such B12 -dummies, either vitamin B12 -derived, or transition metal analogues that also represent potential antivitamins B12 or specific B12 -antimetabolites. As reviewed here, this has opened up new research avenues in organometallic B12 -chemistry and bioinorganic coordination chemistry. Exploratory studies with antivitamins B12 have, furthermore, revealed some of their potential, as pharmacologically interesting compounds, for inducing B12 -deficiency in a range of organisms, from hospital resistant bacteria to laboratory mice. The derived capacity of antivitamins B12 to induce functional B12 -deficiency in mammalian cells and organs also suggest their valuable potential as growth inhibitors of cancerous human and animal cells.


Assuntos
Antimetabólitos , Vitamina B 12 , Animais , Antimetabólitos/química , Antimetabólitos/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Vitamina B 12/antagonistas & inibidores , Vitamina B 12/química , Vitaminas/antagonistas & inibidores , Vitaminas/química
13.
FASEB J ; 33(12): 13669-13682, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31585506

RESUMO

The tick- and transfusion-transmitted human pathogen Babesia microti infects host erythrocytes to cause the pathologic symptoms associated with human babesiosis, an emerging disease with worldwide distribution and potentially fatal clinical outcome. Drugs currently recommended for the treatment of babesiosis are associated with a high failure rate and significant adverse events, highlighting the urgent need for more-effective and safer babesiosis therapies. Unlike other apicomplexan parasites, B. microti lacks a canonical lactate dehydrogenase (LDH) but instead expresses a unique enzyme, B. microti LDH (BmLDH), acquired through evolution by horizontal transfer from a mammalian host. Here, we report the crystal structures of BmLDH in apo state and ternary complex (enzyme-NADH-oxamate) solved at 2.79 and 1.89 Å. Analysis of these structures reveals that upon binding to the coenzyme and substrate, the active pocket of BmLDH undergoes a major conformational change from an opened and disordered to a closed and stabilized state. Biochemical assays using wild-type and mutant B. microti and human LDHs identified Arg99 as a critical residue for the catalytic activity of BmLDH but not its human counterpart. Interestingly, mutation of Arg99 to Ala had no impact on the overall structure and affinity of BmLDH to NADH but dramatically altered the closure of the enzyme's active pocket. Together, these structural and biochemical data highlight significant differences between B. microti and human LDH enzymes and suggest that BmLDH could be a suitable target for the development of selective antibabesial inhibitors.-Yu, L., Shen, Z., Liu, Q., Zhan, X., Luo, X., An, X., Sun, Y., Li, M., Wang, S., Nie, Z., Ao, Y., Zhao, Y., Peng, G., Ben Mamoun, C., He, L., Zhao, J. Crystal structures of Babesia microti lactate dehydrogenase BmLDH reveal a critical role for Arg99 in catalysis.


Assuntos
Arginina/metabolismo , Babesia microti/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , L-Lactato Desidrogenase/química , L-Lactato Desidrogenase/metabolismo , Arginina/química , Babesia microti/efeitos dos fármacos , Babesia microti/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Catálise , Anticoncepcionais Masculinos/farmacologia , Cristalografia por Raios X , Gossipol/farmacologia , L-Lactato Desidrogenase/genética , Modelos Moleculares , Compostos Orgânicos/farmacologia , Conformação Proteica , Especificidade por Substrato
14.
Molecules ; 24(16)2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31405038

RESUMO

There is currently much interest in finding new phytochemicals among plants and fungi as nature-based alternatives to replace problematic herbicides such as glyphosate, which are preferentially used in agricultural production n. We discovered striking herbicidal potency in Cordyceps militaris (L.) and identified cordycepin as its principal plant growth inhibitor. Cordycepin obtained as an ethyl acetate extract was subjected to column chromatography and evaluated for its bioassay-guided phytotoxic capacity against Raphanus sativus (radish), showing a maximum inhibition on germination and growth of radish (IC50 = 0.052-0.078 mg/mL). Gas chromatography-mass spectrometry (GC-MS) (m/z: 251.2) and liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) ([M + Na]+ m/z: 274.1; [M + H]+ m/z: 252.1) analyses confirmed cordycepin as the major component of the tested column fraction (55.38%). At 0.04 mg/mL, cordycepin showed 3.8-5.9- and 3.3-3.7-fold greater inhibition of the germination and growth of radish than benzoic acid (BA) and glyphosate, respectively. Compared with BA, isolated cordycepin reduced plant chlorophyll and carotenoid contents (2.0-9.5 -fold), while proline, total phenolic and total flavonoid contents were increased 1.2-1.8-fold. Finally, cordycepin promoted electrolyte leakage and malondialdehyde accumulation in radish aerial parts. Thus, cordycepin successfully isolated from Cordyceps militaris is a highly potent plant growth inhibitor with pending worldwide patent and may become a potential plant-based novel alternative to the disputed glyphosate.


Assuntos
Cordyceps/química , Desoxiadenosinas , Herbicidas , Raphanus/crescimento & desenvolvimento , Desoxiadenosinas/química , Desoxiadenosinas/isolamento & purificação , Desoxiadenosinas/farmacologia , Glicina/análogos & derivados , Herbicidas/química , Herbicidas/isolamento & purificação , Herbicidas/farmacologia , Glifosato
15.
Bioorg Med Chem ; 26(16): 4745-4750, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30122283

RESUMO

A novel, green fluorescent ß-alanylstyrylcoumarin derivative was synthesized and evaluated for its performance as a fluorogenic enzyme substrate on a range of clinically relevant microorganisms. The substrate was selectively hydrolysed by ß-alanyl aminopeptidase producing P. aeruginosa resulting in an on-to-off fluorescent signal. Growth inhibitory effect of the substrate was observed on Gram positive bacteria and yeasts. Meanwhile, Gram negative species, despite their extremely protective cell envelope, showed ready uptake and accumulation of the substrate within their healthy growing colonies displaying intense green fluorescence.


Assuntos
Antígenos CD13/metabolismo , Cumarínicos/química , Corantes Fluorescentes/química , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Cumarínicos/metabolismo , Cumarínicos/farmacologia , Corantes Fluorescentes/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Pseudomonas aeruginosa/enzimologia , Especificidade por Substrato , Leveduras/efeitos dos fármacos , Leveduras/crescimento & desenvolvimento
16.
Molecules ; 23(8)2018 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30065174

RESUMO

Piper methysticum (kava) root is known to possess promising weed suppressing activity. The present study was conducted to search for potent plant growth inhibitors from the root of this medicinal pepper plant. The ethyl acetate (EtOAc) extract exhibited the strongest reduction on growth of Raphanus sativus (radish) (IC50 shoot and root growth = 172.00 and 51.31 µg/mL respectively) among solvent extracts. From this active extract, nine potent growth inhibitors involved in the inhibitory activities of P. methysticum root were isolated, purified and characterized by column chromatography (CC), gas chromatography-mass spectrometry (GC-MS), electrospray ionization-mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR). The six fractions purified by CC included two flavanones: 5-hydroxy-4',7-dimethoxyflavanone (C1) and 5,7-dihydroxy-4'-methoxy-6,8-dimethylflavanone (matteucinol, C2) and six kavalactones: 5,6-dehydro-kavain (C3), a mixture of kavain and yagonin (C4), yagonin (C5) and dihydro-5,6-dehydrokavain, 7,8-dihydrokavain, dihydromethysticin and methysticin (C6). The amounts of 5-hydroxy-4',7-dimethoxyflavanone, matteucinol, 5,6-dehydrokavain and yangonin were 0.76, 2.50, 2.75 and 2.09 mg/g dry weight (DW), respectively. The two flavanones C1 and C2 exhibited the strongest inhibition on shoot elongation (IC50 = 120.22 and 248.03 µg/mL, respectively), whilst the two kavalactone mixtures C4 and C6 showed the highest suppression on root growth of R. sativus (IC50 = 7.70 and 15.67 µg/mL, respectively). This study was the first to report the purification and inhibitory activities of the two flavanones 5-hydroxy-4',7-dimethoxyflavanone and matteucinol in P. methysticum root. The isolated constituents from P. methysticum root including the flavanones C1 and C2 and the mixtures C4 and C6 may possess distinct modes of action on plant growth. Findings of this study highlighted that the combinations of hexane-ethyl acetate by 9:1 and 8:2 ratios successfully purified flavanones and kavalactones in P. methysticum root.


Assuntos
Flavanonas/isolamento & purificação , Herbicidas/isolamento & purificação , Kava/química , Lactonas/isolamento & purificação , Reguladores de Crescimento de Plantas/isolamento & purificação , Plantas Daninhas/efeitos dos fármacos , Acetatos/química , Flavanonas/classificação , Flavanonas/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Herbicidas/classificação , Herbicidas/farmacologia , Kava/metabolismo , Lactonas/classificação , Lactonas/farmacologia , Estrutura Molecular , Extratos Vegetais/química , Reguladores de Crescimento de Plantas/classificação , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Plantas Daninhas/crescimento & desenvolvimento , Plantas Medicinais , Raphanus/efeitos dos fármacos , Raphanus/crescimento & desenvolvimento , Solventes/química , Controle de Plantas Daninhas/métodos
17.
Tumour Biol ; 37(7): 9121-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26768609

RESUMO

Vascular endothelial growth inhibitor (VEGI) is an anti-angiogenic protein, which includes three isoforms: VEGI-174, VEGI-192, and VEGI-251. The NGR (asparagine-glycine-arginine)-containing peptides can specifically bind to CD13 (Aminopeptidase N) receptor which is overexpressed in angiogenic blood vessels and tumor cells. In this study, a novel NGR-VEGI fusion protein was prepared and labeled with (188)Re for radioimaging and radiotherapy in mice bearing human fibrosarcoma HT-1080 xenografts. Single photon emission computerized tomography (SPECT) imaging results revealed that (188)Re-NGR-VEGI exhibits good tumor-to-background contrast in CD13-positive HT-1080 tumor xenografts. The CD13 specificity of (188)Re-NGR-VEGI was further verified by significant reduction of tumor uptake in HT-1080 tumor xenografts with co-injection of the non-radiolabeled NGR-VEGI protein. The biodistribution results demonstrated good tumor-to-muscle ratio (4.98 ± 0.25) of (188)Re-NGR-VEGI at 24 h, which is consistent with the results from SPECT imaging. For radiotherapy, 18.5 MBq of (188)Re-NGR-VEGI showed excellent tumor inhibition effect in HT-1080 tumor xenografts with no observable toxicity, which was confirmed by the tumor size change and hematoxylin and eosin (H&E) staining of major mouse organs. In conclusion, these data demonstrated that (188)Re-NGR-VEGI has the potential as a theranostic agent for CD13-targeted tumor imaging and therapy.


Assuntos
Fibrossarcoma/radioterapia , Isótopos/metabolismo , Receptor Nogo 1/metabolismo , Rênio/metabolismo , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Animais , Antígenos CD13/metabolismo , Linhagem Celular Tumoral , Feminino , Xenoenxertos/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Peptídeos/metabolismo , Cintilografia/métodos , Distribuição Tecidual/fisiologia
18.
Chem Biodivers ; 13(5): 549-54, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27088639

RESUMO

Aglaia odorata Lour. (Meliaceae) was found to have very strong allelopathic activity and a bioherbicide PORGANIC(™) was developed from its leaf extracts. However, the phytotoxic substances causing the strong allelopathic activity of the plants have not yet been determined. Therefore, we investigated allelopathic properties and phytotoxic substances in A. odorata. Aqueous EtOH extracts of A. odorata leaves inhibited root and shoot growth of garden cress (Lepidum sativum), lettuce (Lactuca sativa), alfalfa (Medicago sativa), timothy (Phleum pratense), ryegrass (Lolium multiflorum), and Echinochloa crus-galli with the extract concentration-dependent manner. The extracts were then purified and a major phytotoxic substance with allelopathic activity was isolated and identified by spectral data as rocaglaol. Rocaglaol inhibited the growth of garden cress and E. crus-galli at concentrations > 0.3 and 0.03 µm, respectively. The concentrations required for 50% inhibition ranged from 0.09 to 2.5 µm. The inhibitory activity of rocaglaol on the weed species, E. crus-galli, was much greater than that of abscisic acid. These results suggest that rocaglaol may be a major contributor to the allelopathic effect of A. odorata and bioherbicide PORGANIC(™) .


Assuntos
Aglaia/química , Benzofuranos/farmacologia , Echinochloa/efeitos dos fármacos , Lepidium sativum/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química , Benzofuranos/química , Benzofuranos/isolamento & purificação , Relação Dose-Resposta a Droga , Echinochloa/crescimento & desenvolvimento , Lepidium sativum/crescimento & desenvolvimento , Conformação Molecular
19.
Chin J Cancer Res ; 28(4): 435-43, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27647972

RESUMO

OBJECTIVE: The inhibition of the neovascularization in tumors is a potential therapeutic target of cancer. Vascular endothelial growth inhibitor (VEGI) is a member of the TNF superfamily which has the ability to suppress the formation of new vessels in tumors. In order to study the association between VEGI gene polymorphisms and breast cancer risk, a case-control study was conducted in Chinese Han women in Northeast China. METHODS: Our study involved 708 female breast cancer patients and 685 healthy volunteers. Four SNPs of VEGI gene were analyzed through the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The association between VEGI gene polymorphisms and breast cancer risk was analyzed in our study. The relation between VEGI gene variants and clinical features of breast cancer including lymph node (LN) metastasis, estrogen receptor (ER), progestrogen receptor (PR), tumor protein 53 (p53), human epidermal growth factor receptor 2 (Her-2) and triple negative (ER-/PR-/Her-2-) status was analyzed as well. RESULTS: We found that the CT genotype and T allele of rs6478106 were more frequent in patients than in controls. There was also a statistical difference in the distribution of Crs6478106Grs4263839 haplotype between patients and controls. In addition, SNP rs6478106 and rs4979462 were related with the Her-2 status. CONCLUSIONS: Our results suggest that VEGI gene variants may be related to the breast cancer risk and the clinical features of breast cancer in Chinese Han women in Northeast China.

20.
Bioorg Med Chem ; 23(5): 966-75, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25659617

RESUMO

Total syntheses of (+)-dictyoceratin-C (1) and (+)-dictyoceratin-A (smenospondiol) (2), hypoxia-selective growth inhibitors isolated from marine sponge, were executed. The absolute stereochemistry of the each compound was determined through the enantioselective total syntheses of them. It revealed that the unnatural enantiomers of them also exhibited the hypoxia-selective growth inhibitory activity against human prostate cancer DU-145 cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , Inibidores do Crescimento/síntese química , Inibidores do Crescimento/farmacologia , Hidroxibenzoatos/síntese química , Hidroxibenzoatos/farmacologia , Poríferos/química , Sesquiterpenos/síntese química , Sesquiterpenos/farmacologia , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores do Crescimento/química , Humanos , Hidroxibenzoatos/química , Masculino , Biologia Marinha , Neoplasias da Próstata/patologia , Sesquiterpenos/química , Estereoisomerismo
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