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1.
Fish Physiol Biochem ; 50(1): 259-271, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37847337

RESUMO

This study investigated the effect of different levels of digestible protein (DP) on blood metabolites, hepatic enzyme activity of glycolysis and amino acid metabolism, energy reserves, and the production characteristics of pacu (Piaractus mesopotamicus) during the finishing growth phase. Six semi purified and isoenergetic diets, containing 16.3, 20.1, 23.8, 27.2, 31.5, and 34.8% of balanced DP, provided with essential amino acid balance, were hand-fed to pacu (1100.0 ± 10.3 g, initial weight) three times daily for 7 weeks. The experiment consisted of six treatments, with three randomly arranged replicates (tanks) per treatment. The data obtained from this experiment were analyzed by one-way analysis of variance (ANOVA), and significant differences (p < 0.05) between treatments were determined using Tukey's test. Blood metabolites, except serum ammonia and the hepatic enzymes activities of glycolysis and amino acid metabolism, except hexokinase activity were affected (p < 0.05) by balanced DP. The energy reserve indices, except hepatic total lipid content, were also found associated (p < 0.05) with balanced DP. The test diets significantly (p < 0.05) affected growth performance parameters. Higher dietary proteins led to a greater energy uptake by fish from the protein in feed. Overall, fish fed the intermediate level (23.8%) of balanced DP with digestible energy of 17.95 MJ kg-1 showed better production traits and physio-biochemical health markers. This information could help nutritionists and farmers to develop nutritionally balanced and economically and environmentally sustainable aquafeed for promoting healthy and sustainable production of pacu in intensive culture systems.


Assuntos
Caraciformes , Dieta , Animais , Dieta/veterinária , Aminoácidos Essenciais , Proteínas Alimentares/farmacologia , Aumento de Peso , Ração Animal/análise , Metabolismo Energético
2.
Environ Toxicol ; 37(11): 2683-2691, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35920046

RESUMO

Microcystins (MC) are hepatotoxic for organisms. Liver MC accumulation and structural change are intensely studied, but the functional hepatic enzymes and energy metabolism have received little attention. This study investigated the liver and hepatocyte structures and the activity of key hepatic functional enzymes with emphasis on energetic metabolism changes after subchronic fish exposure to cyanobacterial crude extract (CE) containing MC. The Neotropical erythrinid fish, Hoplias malabaricus, were exposed intraperitoneally to CE containing 100 µg MC-LR eq kg-1 for 30 days and, thereafter, the plasma, liver, and white muscle was sampled for analyses. Liver tissue lost cellular structure organization showing round hepatocytes, hyperemia, and biliary duct obstruction. At the ultrastructural level, the mitochondria and the endoplasmic reticulum exhibited disorganization. Direct and total bilirubin increased in plasma. In the liver, the activity of acid phosphatase (ACP) increased, and the aspartate aminotransferase (AST) decreased; AST increased in plasma. Alkaline phosphatase (ALP) and alanine aminotransferase (ALT) were unchanged in the liver, muscle, and plasma. Glycogen stores and the energetic metabolites as glucose, lactate, and pyruvate decrease in the liver; pyruvate decreased in plasma and lactate decreased in muscle. Ammonia levels increased and protein concentration decreased in plasma. CE alters liver morphology by causing hepatocyte intracellular disorder, obstructive cholestasis, and dysfunction in the activity of key liver enzymes. The increasing energy demand implies glucose mobilization and metabolic adjustments maintaining protein preservation and lipid recruitment to supply the needs for detoxification allowing fish survival.


Assuntos
Caraciformes , Cianobactérias , Hepatopatias , Fosfatase Ácida/metabolismo , Alanina Transaminase/metabolismo , Fosfatase Alcalina/metabolismo , Amônia , Animais , Aspartato Aminotransferases/metabolismo , Bilirrubina/metabolismo , Misturas Complexas/metabolismo , Misturas Complexas/toxicidade , Cianobactérias/metabolismo , Glucose/metabolismo , Glicogênio/metabolismo , Lactatos , Lipídeos , Fígado/metabolismo , Hepatopatias/metabolismo , Microcistinas/metabolismo , Microcistinas/toxicidade , Piruvatos/metabolismo
3.
Molecules ; 27(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36558076

RESUMO

Citrus canker, caused by the bacterium Xanthomonas citri subsp. citri (Xcc), is a disease that causes serious problems to the global citrus industry. Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry (MS) has been used in human medicine to diagnose various diseases caused by both fungi and bacteria. In agriculture, this technique has potential for the diagnosis of diseases due to the low cost of large-scale analysis and quickness. This study showed that MALDI-TOF MS combined with chemometric analysis was effective for differentiating the macromolecule profile of orange leaves with canker lesions, healthy leaves, and leaves with phytotoxicity symptoms, proving that this technique may be used for the rapid diagnosis of citrus canker.


Assuntos
Citrus sinensis , Citrus , Xanthomonas , Humanos , Citrus/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Citrus sinensis/microbiologia , Doenças das Plantas/microbiologia
4.
Ecotoxicol Environ Saf ; 208: 111459, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33069948

RESUMO

The flavonoid metal-insecticide [Mg(hesp)2(phen)], denominated MgHP, has high potential for controlling agricultural pests. If applied in large scale, it may reach aquatic ecosystems and be harmful to the biota. This study evaluated the effects of MgHP in the gills of the Neotropical fish, Prochilodus lineatus by determining the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione s-transferase (GST), and the levels of glutathione (GSH) and lipid peroxidation (LPO) after 24 and 96 h exposure to 0, 1, 10, 100 and 1000 µg L-1. The histopathological changes with emphases to mitochondria-rich cells (MRC) were evaluated as well. After 24 h exposure the enzyme activities and the GSH and LPO levels were unchanged however, after 96 h exposure to high MgHP concentration (1000 µg L-1), the GST activity and GSH levels increased. Oxidative stress measured as LPO levels did not occur after MgHP exposure in both periods. Gill tissue alterations increased after MgHP exposure to 10, 100 and 1000 µg L-1. Cellular atrophy, pillar cells changes, filament epithelium hyperplasia and hypertrophy, lamellar epithelium hyperplasia were the most frequent histopathology. MRC in the filament epithelium decreased after exposure to 24 h and increased after 96 h indicating possible transitory osmo-ionic disruption. P. lineatus exhibited high tolerance to MgHP. The increased GST activity and GSH levels after 96 h exposure suggested possible MgHP accumulation and concentration- and time-dependent response. Histopathology in the gills of exposed fish occurred at high MgHP concentrations. These results suggested that the MgHP into water, at high concentrations, affect the gills by changing GST activity, GSH levels and histology being useful biomarkers for MgHP water contamination.


Assuntos
Peixes/fisiologia , Brânquias/efeitos dos fármacos , Inseticidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Caraciformes/metabolismo , Ecossistema , Flavonoides/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Metais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/metabolismo
5.
Lasers Med Sci ; 36(4): 863-870, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32827076

RESUMO

Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The polysaccharide fraction (LBPF) isolated from Lycium Barbarum fruits (goji berry) contains several active ingredients with antioxidant, immune system modulation, and antitumor effects. In addition, the photobiomodulation (PBM) is widely applied in photoaging treatment. This study investigated the effects of LBPF and PBM against the UVR-induced photodamage in the skin of hairless mice. The mice were photoaged for 6 weeks in a chronic and cumulative exposure regimen using a 300-W incandescent lamp that simulates the UVR effects. From the third to the sixth week of photoaging induction, the animals received topical applications of LBPF and PBM, singly or combined, in different orders (first LBPF and then PBM and inversely), three times per week after each session of photoaging. After completion of experiments, the dorsal region skin was collected for the analysis of thickness, collagen content, and metalloproteinases (MMP) levels. A photoprotective potential against the increase of the epithelium thickness and the fragmentation of the collagen fibers was achieved in the skin of mice treated with LBPF or PBM singly, as well as their combination. All treatments maintained the skin collagen composition, except when PBM was applied after the LBPF. However, no treatment protected against the UVR-induced MMP increase. Taken together, we have shown that the LBPF and PBM promote a photoprotective effect in hairless mice skin against epidermal thickening and low collagen density. Both strategies, singly and combined, can be used to reduce the UVR-induced cutaneous photoaging.


Assuntos
Colágeno/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Epitélio/efeitos dos fármacos , Epitélio/efeitos da radiação , Terapia com Luz de Baixa Intensidade , Pele/patologia , Pele/efeitos da radiação , Animais , Epitélio/patologia , Camundongos , Camundongos Pelados , Pele/efeitos dos fármacos , Pele/metabolismo , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/patologia , Envelhecimento da Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos
6.
Wound Repair Regen ; 28(5): 645-655, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32590890

RESUMO

Prolonged skin exposure to ultraviolet radiation (UVR) induces premature aging in both the epidermis and the dermis. Chronic exposure to UVR induces the activation of mitogen-activated protein kinase (MAPK) signaling pathway, activating c-Jun, c-Fos expression, and transcription factor of AP-1 activating protein. AP-1 activation results in the positive induction of matrix metalloproteinase (MMP) synthesis, which degrade skin collagen fibers. Polysaccharides from the fruit of Lycium barbarum (LBP fraction) have a range of activities and have been demonstrate to repair the photodamage. In different approaches, laser application aims to recover the aged skin without destroying the epidermis, promoting a modulation, called photobiomodulation (PBM), which leads to protein synthesis and cell proliferation, favoring tissue repair. Here we developed a topical hydrogel formulation from a polysaccharide-rich fraction of Lycium barbarum fruits (LBP). This formulation was associated with PBM (red laser) to evaluate whether the isolated and combined treatments would reduce the UVR-mediated photodamage in mice skin. Hairless mice were photoaged for 6 weeks and then treated singly or in combination with LBP and PBM. Histological, immunohistochemistry, and immunofluorescence analyses were used to investigate the levels of c-Fos, c-Jun, MMP-1, -2, and -9, collagen I, III, and FGF2. The combined regimen inhibited UVR-induced skin thickening, decreased the expression of c-Fos and c-Jun, as well as MMP-1, -2, and -9 and concomitantly increased the levels of collagen I, III, and FGF2. The PBM in combination with LBP treatment is a promising strategy for the repair of photodamaged skin, presenting potential clinical application in skin rejuvenation.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Hidrogéis/farmacologia , Terapia com Luz de Baixa Intensidade , Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Cicatrização/efeitos dos fármacos , Cicatrização/efeitos da radiação , Animais , Modelos Animais de Doenças , Feminino , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Camundongos , Camundongos Pelados , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Transdução de Sinais , Fator de Transcrição AP-1/metabolismo
7.
Rapid Commun Mass Spectrom ; 34 Suppl 3: e8745, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32053855

RESUMO

RATIONALE: Xylella fastidiosa causes citrus variegated chlorosis (CVC) in sweet orange trees. A diagnostic method for detecting CVC before the symptoms appear, which would inform citrus producers in advance about when the plant should be removed from the orchard, is essential for reducing pesticide application costs. METHODS: Chemometrics was applied to high-performance liquid chromatography diode array detector (HPLC-DAD) data to evaluate the similarities and differences between the chromatographic profiles. A liquid chromatography/atmospheric pressure chemical ionization mass spectrometry selected reaction monitoring (LC/APCI-MS-SRM) method was developed to identify the major compounds and to determine their amounts in all samples. RESULTS: We evaluated the effect of this bacterium on the variation in the chemical profile in citrus plants. The organs of C. sinensis grafted on C. limonia were analyzed. Chemometrics was applied to the obtained data, and two major groups were differentiated. Flavonoids were observed in one group (leaves) and coumarins in the second (roots), both at higher concentrations in the plants with CVC symptoms than in those without the symptoms and those in the negative control. The rootstocks also interfered in the metabolism of the scion. CONCLUSIONS: The developed LC/APCI-MS-SRM method for detecting CVC before the symptoms appear is simple and accurate. It is inexpensive, and many samples can be screened per hour using 1 mg of leaves. Knowledge of the influence of the rootstock on the chemical profile of the graft is limited. This study demonstrates the effect of the rootstock in synthesizing flavonoids and increasing its content in all parts of the graft.


Assuntos
Citrus sinensis/química , Citrus sinensis/microbiologia , Doenças das Plantas/microbiologia , Espectrometria de Massas em Tandem/métodos , Quimioinformática , Cromatografia Líquida de Alta Pressão , Cumarínicos/análise , Resistência à Doença , Melhoramento Vegetal/métodos , Folhas de Planta/química , Folhas de Planta/microbiologia , Raízes de Plantas/química , Raízes de Plantas/microbiologia , Caules de Planta/química , Caules de Planta/microbiologia , Xylella/patogenicidade
8.
J Anim Physiol Anim Nutr (Berl) ; 103(4): 1168-1173, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31062424

RESUMO

Experiments were conducted to estimate daily N maintenance requirements (NMRs) and the genetic potential for daily N retention (NRmax T) of pullets in growth phase. Three nitrogen balance trials were conducted, and a total of 48 Hy-line W-36 pullets were used in each trial in age periods (starter: 14-28, grower: 56-70 and developer: 98-112 days). The treatments consisted of six graded levels of nitrogen in the diets (L1 = 8, L2 = 16, L3 = 24, L4 = 32, L5 = 40 and L6 = 48 g N/kg of feed), formulated using the dilution technique. The regression analyses between nitrogen intake and nitrogen excretion were performed to fit the exponential function and to determine the NMR. The daily NMRs that were estimated at 294, 331 and 355 mg/BWkg 0.67 for the initial, grower and developer periods, respectively, were applied for further calculation of NRmax T as the threshold value of the function between N intake and daily N balance. The NRmax T was estimated by a statistical procedure following several iteration steps by the Levenberg-Marquardt algorithm until the sum of the squares of the residual was minimized. The NRmax T was estimated at 3,200, 2,633 and 1,826 mg/BWkg 0.67 for starter, grower and developer periods respectively. The determined model parameters were the precondition for modelling of the amino acid requirement based on an exponential N-utilization model and depended on performance and dietary amino acid efficiency. This procedure will be further developed and applied in the subsequent study.


Assuntos
Ração Animal/análise , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Nitrogênio/administração & dosagem , Nitrogênio/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/metabolismo , Feminino , Necessidades Nutricionais
9.
Molecules ; 23(11)2018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30413007

RESUMO

A high performance liquid chromatography (HPLC) method was developed for the simultaneous isolation, on a semi-preparative scale, of chavibetol and methyleugenol from the crude essential oil of P. pseudocaryophyllus leaves. The purity of the isolated compounds and their quantifications were developed using GC/FID. Chavibetol was isolated with high purity (98.7%) and mass recovery (94.6%). The mass recovery (86.4%) and purity (85.3%) of methyleugenol were lower than those of chavibetol. Both compounds were identified on the basis of spectral analysis. The results suggest that the method can provide chavibetol with high purity, mass recovery, and productivity from crude essential, which will be used in bioassays against stored insect pests.


Assuntos
Eugenol/análogos & derivados , Pimenta/química , Cromatografia Líquida de Alta Pressão , Eugenol/isolamento & purificação , Óleos Voláteis/química , Folhas de Planta/química , Óleos de Plantas/química
10.
J Aquat Anim Health ; 30(3): 210-216, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29845639

RESUMO

For the production and commercialization of ornamental fish species, it is indispensable to collect biometric data that facilitate the selection of animals for trade and genetic improvement of the stock. However, during the handling process, fish receive more stress if proper anesthetics are not used. Thus, application of appropriate anesthetics is an important tool for minimizing stress in animals. The objective of this study was to determine the effective concentrations of benzocaine, eugenol, and menthol for achieving anesthesia in Freshwater Angelfish Pterophyllum scalare and to develop induction and recovery response curves for different concentrations of these anesthetics. In total, 75 fish were exposed to five concentrations of the three anesthetics in a completely randomized design: benzocaine at 60, 85, 110, 135, and 160 mg/L; eugenol at 40, 80, 120, 160, and 200 mg/L; and menthol at 50, 75, 150, 200, and 250 mg/L. Each concentration (5 fish/concentration) consisted of five replicates, with each replicate represented by a single fish. The results indicated that the tested substances met the criteria of anesthetic efficiency. The effective concentrations of benzocaine, eugenol, and menthol for the anesthesia of Freshwater Angelfish were identified as 89.25, 90.6, and 92.1 mg/L, respectively.


Assuntos
Anestesia/veterinária , Anestésicos/efeitos adversos , Benzocaína/efeitos adversos , Ciclídeos/fisiologia , Eugenol/efeitos adversos , Mentol/efeitos adversos , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino , Distribuição Aleatória
11.
ScientificWorldJournal ; 2017: 4927214, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28116346

RESUMO

The essential oil was obtained by hydrodistillation and the identification and quantification of components were achieved with the use of GC-MS analysis. The antioxidant activity was evaluated by the method of sequestration of DPPH. Essential oils were used for study the cytotoxic front larvae of Artemia salina. In the evaluation of the antimicrobial activity of essential oils, we employed the disk-diffusion method. The potential larvicide in mosquito larvae of the third stage of development of Aedes aegypti to different concentrations of essential oils was evaluated. The major compounds found in the essential oils of M. piperita were linalool (51.8%) and epoxyocimene (19.3%). The percentage of antioxidant activity was 79.9 ± 1.6%. The essential oil showed LC50 = 414.6 µg/mL front of A. saline and is considered highly toxic. It shows sensitivity and halos significant inhibition against E. coli. The essential possessed partial larvicidal efficiency against A. aegypti.


Assuntos
Mentha piperita/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Aedes , Animais , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Artemia/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Inseticidas , Larva
12.
Molecules ; 22(6)2017 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-28608830

RESUMO

Diketopiperazines can be generated by non-enzymatic cyclization of linear dipeptides at extreme temperature or pH, and the complex medium used to culture bacteria and fungi including phytone peptone and trypticase peptone, can also produce cyclic peptides by heat sterilization. As a result, it is not always clear if many diketopiperazines reported in the literature are artifacts formed by the different complex media used in microorganism growth. An ideal method for analysis of these compounds should identify whether they are either synthesized de novo from the products of primary metabolism and deliver true diketopiperazines. A simple defined medium (X. fastidiosa medium or XFM) containing a single carbon source and no preformed amino acids has emerged as a method with a particularly high potential for the grown of X. fastidiosa and to produce genuine natural products. In this work, we identified a range of diketopiperazines from X. fastidiosa 9a5c growth in XFM, using Ultra-Fast Liquid Chromatography coupled with mass spectrometry. Diketopiperazines are reported for the first time from X. fastidiosa, which is responsible for citrus variegated chlorosis. We also report here fatty acids from X. fastidiosa, which were not biologically active as diffusible signals, and the role of diketopiperazines in signal transduction still remains unknown.


Assuntos
Dicetopiperazinas/farmacologia , Peptonas/química , Xylella/efeitos dos fármacos , Carbono/química , Caseínas/química , Cromatografia Líquida , Dicetopiperazinas/síntese química , Dicetopiperazinas/química , Peptonas/síntese química , Peptonas/farmacologia , Hidrolisados de Proteína/química , Espectrometria de Massas por Ionização por Electrospray , Xylella/crescimento & desenvolvimento
13.
Fish Physiol Biochem ; 43(6): 1689-1705, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28712005

RESUMO

In the present review, the ongoing researches about selenium research in fish nutrition have been comprehensively discussed. Selenium research is getting popularity in fish nutrition as it is required for the normal growth and proper physiological and biochemical functions in fish. Its deficiency or surplus amounts create severe problems in fish. It is available as inorganic form, organic form, and nano form. In fish, most of the previous research is about the selenium requirements for fish by using only one selenium source mainly the inorganic one. Selenium shows maximum biological activity and bioavailability when it is supplied in proper form. However, to differentiate the more bioavailable and less toxic form of selenium, sufficient information is needed about the comparative bioavailability of different selenium forms in different fish species. In fish, important data about the new forms of selenoproteins is still scarce. Therefore, it is necessary to focus on the determination and elucidation of the new selenoproteins in fish through the utilization of recent approaches of molecular biology and proteomics. The adaptation of these new approaches will replace the old fashioned methodologies regarding the selenium research in fish nutrition. Moreover, the use of molecular biology and proteomics-based new approaches in combination with selenium research will help in optimizing the area of fish nutrition and will improve the feed intake, growth performance, and more importantly the flesh quality which has a promising importance in the consumer market.


Assuntos
Dieta/veterinária , Peixes/fisiologia , Selênio/administração & dosagem , Selênio/farmacologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Necessidades Nutricionais
14.
Molecules ; 21(6)2016 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-27338332

RESUMO

The chemical composition of volatile oils from 22 genotypes of Citrus and related genera was poorly differentiated, but chemometric techniques have clarified the relationships between the 22 genotypes, and allowed us to understand their resistance to D. citri. The most convincing similarities include the synthesis of (Z)-ß-ocimene and (E)-caryophyllene for all 11 genotypes of group A. Genotypes of group B are not uniformly characterized by essential oil compounds. When stimulated with odor sources of 22 genotypes in a Y-tube olfactometer D. citri preferentially entered the arm containing the volatile oils of Murraya paniculata, confirming orange jasmine as its best host. C. reticulata × C. sinensis was the least preferred genotype, and is characterized by the presence of phytol, (Z)-ß-ocimene, and ß-elemene, which were not found in the most preferred genotype. We speculate that these three compounds may act as a repellent, making these oils less attractive to D. citri.


Assuntos
Citrus/efeitos dos fármacos , Hemípteros/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Animais , Brasil , Citrus/genética , Citrus/parasitologia , Genótipo , Hemípteros/patogenicidade , Repelentes de Insetos/química , Repelentes de Insetos/farmacologia , Óleos Voláteis/química , Fitol/química , Fitol/farmacologia , Óleos de Plantas/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia
15.
Bioorg Med Chem ; 23(3): 466-70, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25564380

RESUMO

NS2B-NS3 is a serine protease of the Dengue virus considered a key target in the search for new antiviral drugs. In this study flavonoids were found to be inhibitors of NS2B-NS3 proteases of the Dengue virus serotypes 2 and 3 with IC50 values ranging from 15 to 44 µM. Agathisflavone (1) and myricetin (4) turned out to be noncompetitive inhibitors of dengue virus serotype 2 NS2B-NS3 protease with Ki values of 11 and 4.7 µM, respectively. Docking studies propose a binding mode of the flavonoids in a specific allosteric binding site of the enzyme. Analysis of biomolecular interactions of quercetin (5) with NT647-NHS-labeled Dengue virus serotype 3 NS2B-NS3 protease by microscale thermophoresis experiments, yielded a dissociation constant KD of 20 µM. Our results help to understand the mechanism of inhibition of the Dengue virus serine protease by flavonoids, which is essential for the development of improved inhibitors.


Assuntos
Vírus da Dengue/enzimologia , Flavonoides/farmacologia , Serina Endopeptidases/química , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/farmacologia , Antivirais/química , Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Flavonoides/química , Cinética , Modelos Moleculares , Simulação de Acoplamento Molecular , Serina Endopeptidases/metabolismo , Relação Estrutura-Atividade
16.
Zygote ; 23(2): 237-46, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24229578

RESUMO

Oscar (Astronotus ocellatus) is an important fish from the Amazon Basin that has great potential for fish farming, human consumption, sport fishing and fish keeping. This study aimed to evaluate the effect of two hormonal treatments on the induction of artificial reproduction in broodstock and to describe the histological development of embryos and larvae. Broodstocks were selected and induced using two different hormones: (i) extract of carp pituitary (ECP); and (ii) synthetic human chorionic gonadotropin (hCG). Spawnings were transferred to hatcheries, collected at pre-established times, processed and analysed by histology. Astronotus ocellatus did not respond well to induced reproduction. From 16 couples of breeding fish, only five out of the eight females released oocytes after the hormonal action time, three with hCG and two with ECP; just one male responded positively to hCG. Oscar eggs were oval, and semi-adhesive, the yolk contained granules, and egg diameter was approximately 1.65 ± 0.057 to 1.98 ± 0.038 mm. Development from the initial collection (IC) point until the total absorption of the yolk lasted 315 h, at an average temperature of 27.45 ± 2.13°C. Several events marked embryonic and larval development, including the formation of the optic cup, forebrain, otic vesicle and cephalic divisions. The newly hatched larvae had non-pigmented eyes, and a closed mouth and anus, as well as the presence of adhesive glands on the head. Larval development was characterized by formation of the heart, liver, gaseous bladder, gills, pronephros, brain, fins and also the digestive tract. These results provide important information for the rearing and reproduction of A. ocellatus.


Assuntos
Gonadotropina Coriônica/farmacologia , Ciclídeos/embriologia , Ciclídeos/crescimento & desenvolvimento , Reprodução/efeitos dos fármacos , Animais , Aquicultura/métodos , Carpas , Ciclídeos/fisiologia , Embrião não Mamífero/citologia , Embrião não Mamífero/efeitos dos fármacos , Feminino , Larva/efeitos dos fármacos , Larva/fisiologia , Masculino , Oócitos/citologia , Oócitos/efeitos dos fármacos , Hipófise/química , Extratos de Tecidos/farmacologia
17.
Zygote ; 23(2): 247-56, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24229611

RESUMO

Betta splendens is a very important ornamental species. The current paper describes the embryonic and larval development of B. splendens under stereomicroscopy and scanning electron microscopy. Eggs and larvae from natural spawning were collected at different developmental stages at previously established intervals and analysed. The eggs of B. splendens are yellowish, clear, spherical, demersal, translucent and telolecithal with a large amount of yolk. Between 0-2 h post-initial collection (hpIC), the eggs were at the egg cell, first cleavage and morula stages. The blastula stage was identified at 2-3 hpIC and the early gastrula phase was observed at 3-4 hpIC with 20% epiboly, which was finalized after 13-18 hpIC. When the pre-larvae were ready to hatch, the appearance of somites and the free tail were observed, at 23-25 hpIC. At 29 hpIC, the majority of larvae had already hatched at an average temperature of 28.4 ± 0.2°C. The newly hatched larvae measured 2.47 ± 0.044 mm total length. The mouth opened at 23 h post-hatching (hPH) and the yolk sac was totally absorbed at 73 hPH. After 156 hPH, the heart was pumping blood throughout the entire larval body. The caudal fin, operculum and eyes were well developed at 264 hPH. When metamorphosis was complete at 768 hPH, the larvae became juveniles. The current study presents the first results about early development of B. splendens and provides relevant information for its reproduction, rearing and biology.


Assuntos
Embrião não Mamífero/citologia , Perciformes/embriologia , Perciformes/crescimento & desenvolvimento , Nadadeiras de Animais/crescimento & desenvolvimento , Animais , Blastocisto/citologia , Olho/crescimento & desenvolvimento , Feminino , Gástrula/citologia , Larva/crescimento & desenvolvimento , Masculino , Microscopia Eletrônica de Varredura
18.
J Nat Prod ; 77(11): 2418-22, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25375026

RESUMO

Metrodorea stipularis stem extracts were studied in the search for possible antichagastic, antimalarial, and antitumoral compounds using cruzain from Trypanosoma cruzi, Plasmodium falciparum, and cathepsins B and L, as molecular targets, respectively. Dihydrochalcones 1, 2, 3, and 4 showed significant inhibitory activity against all the targets. Compounds 1-4 displayed IC50 values ranging from 7.7 to 21.6 µM against cruzain; dihydrochalcones 2 and 4 inhibited the growth of three different strains of P. falciparum in low micromolar concentrations; and against cathepsins B and L these compounds presented good inhibitory activity with IC50 values ranging from 1.0 to 14.9 µM. The dihydrochalcones showed good selectivity in their inhibitory activities against the cysteine proteases.


Assuntos
Antiprotozoários , Chalconas , Antimaláricos/química , Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Brasil , Catepsina B/antagonistas & inibidores , Catepsina L/antagonistas & inibidores , Chalconas/química , Chalconas/isolamento & purificação , Chalconas/farmacologia , Concentração Inibidora 50 , Estrutura Molecular , Testes de Sensibilidade Parasitária , Caules de Planta/química , Plasmodium falciparum/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos
19.
J Nat Prod ; 77(2): 392-6, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24521209

RESUMO

Byrsonima coccolobifolia leaf and stem extracts were studied in the search for possible leishmanicidal compounds using arginase (ARG) from Leishmania amazonensis as a molecular target. Flavonoids 1b, 1e-1g, 2a, 2b, and 2d-2f showed significant inhibitory activity, with IC50 values ranging from 0.9 to 4.8 µM. The kinetics of the most active compounds were determined. Flavonoids 1e, 1f, 2a, 2b, and 2e were characterized as noncompetitive inhibitors of ARG with dissociation constants (Ki) ranging from 0.24 to 3.8 µM, demonstrating strong affinity. Structure-activity relationship studies revealed some similarities in the structural features of flavonoids related to ARG activity.


Assuntos
Arginase/antagonistas & inibidores , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Leishmania/efeitos dos fármacos , Malpighiaceae/química , Brasil , Flavonoides/química , Concentração Inibidora 50 , Estrutura Molecular , Folhas de Planta/química , Caules de Planta/química , Relação Estrutura-Atividade
20.
Z Naturforsch C J Biosci ; 78(5-6): 229-233, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-36572526

RESUMO

The aim of the study was to evaluate the effects of the seeds, exocarp and aril extracts from Trichilia catigua A. Juss. (Meliaceae) against Spodoptera frugiperda and present the phytochemical study carried out with the aril extract of T. catigua. Limonoids were isolated from the aril of T. catigua through chromatographic techniques and their structures were proposed by spectroscopic analysis and comparison with literature data. The effects of the seeds, exocarp and aril extracts from T. catigua against S. frugiperda were evaluated considering as parameters the duration and mortality of the larval phase, in addition to the pupal weight. Phytochemical investigation of the aril extracts of T. catigua has led to the identification of the limonoids 6α-O-acetyl-7-deacetyl-14,15-dihydro-15-oxo-nimocinol (1), cedrelone (2) and 6α-O-acetyl-7-deacetylnimocinol (3). The hexane and CH2Cl2 extracts of the aril showed a high rate of larval mortality (100 and 90%, respectively). In addition, a prolongation of larval phase and a reduction in the pupal weight were observed for insects treated with hexane, CH2Cl2 and methanol extracts of seeds and with CH2Cl2 extract of exocarp of T. catigua.


Assuntos
Inseticidas , Limoninas , Meliaceae , Animais , Inseticidas/farmacologia , Spodoptera , Limoninas/farmacologia , Hexanos , Extratos Vegetais/farmacologia , Meliaceae/química , Larva
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