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1.
Sci Rep ; 11(1): 16479, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389753

RESUMO

The purpose of the present study was to compare the relative absorption of a new powder presentation of silicon (Si) as orthosilicic acid with maltodextrin (Orgono Powder) compared to usual Si liquid presentations as orthosilicic acid with Equisetum arvense and Rosmarinus officinalis (G5 Siliplant) and orthosilicic acid with aloe vera (G7 Aloe). All dietary supplements were administered at the same Si oral dose (21.6 mg) in a randomized, double-blind, crossover post-prandial study conducted in 5 healthy men. Urine was collected at baseline and over the 6-h post-dose period in 2 separate 3-h collections for the analysis of Si concentration, which was conducted by inductively coupled plasma optical emission spectrometry as the gold standard method. No significant differences in total urinary Si excretion were found after the intake of these 3 dietary supplements; 34.6%, 32.4% and 27.2% of the ingested Si from G7 Aloe, G5 Siliplant and Orgono Powder, respectively, was excreted in urine over the 6-h follow-up period. The 3 different oral Si formulations tested, in powder and liquid presentations, provide highly bioavailable Si and present an equivalent relative absorption in healthy humans.


Assuntos
Suplementos Nutricionais , Silício/farmacocinética , Adulto , Aloe , Estudos Cross-Over , Método Duplo-Cego , Equisetum , Humanos , Absorção Intestinal , Masculino , Projetos Piloto , Extratos Vegetais/farmacocinética , Polissacarídeos/farmacologia , Período Pós-Prandial , Rosmarinus , Ácido Silícico/farmacocinética , Ácido Silícico/urina , Silício/urina
2.
Molecules ; 26(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924900

RESUMO

The sterile stems belonging to the Equisetum species are often used in traditional medicine of various nations, including Romanians. They are highly efficient in treating urinary tract infections, cardiovascular diseases, respiratory tract infections, and medical skin conditions due to their content of polyphenolic derivatives that have been isolated. In this regard, this study aimed to provide the chemical composition of the extracts obtained from the Equisetum species (E. pratense, E. sylvaticum, E. telmateia) and to investigate the biological action in vitro and in vivo. For the chemical characterization of the analyzed Equisetum species extracts, studies were performed by using ultra-high-performance liquid chromatography (UHPLC-DAD). In vitro evaluation of the antioxidant activity of the plant extracts obtained from these species of Equisetum genus was determined. The neuroprotective activity of these three ethanolic extracts from the Equisetum species using zebrafish tests was determined in vivo. All obtained results were statistically significant. The results indicate that E. sylvaticum extract has a significant antioxidant activity; whereas, E. pratense extract had anxiolytic and antidepressant effects significantly higher than the other two extracts used. All these determinations indicate promising results for the antioxidant in vitro tests and neuroprotective activity of in vivo tests, particularly mediated by their active principles.


Assuntos
Antioxidantes/farmacologia , Equisetum/química , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Animais , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Fármacos Neuroprotetores/química , Extratos Vegetais/química , Polifenóis/química , Polifenóis/farmacologia , Sensibilidade e Especificidade , Peixe-Zebra
3.
Ann Bot ; 127(5): 681-695, 2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33598697

RESUMO

BACKGROUND AND AIMS: Extant plant groups with a long fossil history are key elements in understanding vascular plant evolution. Horsetails (Equisetum, Equisetaceae) have a nearly continuous fossil record dating back to the Carboniferous, but their phylogenetic and biogeographic patterns are still poorly understood. We use here the most extensive phylogenetic analysis to date as a framework to evaluate their age, biogeography and genome size evolution. METHODS: DNA sequences of four plastid loci were used to estimate divergence times and investigate the biogeographic history of all extant species of Equisetum. Flow cytometry was used to study genome size evolution against the framework of phylogenetic relationships in Equisetum. KEY RESULTS: On a well-supported phylogenetic tree including all extant Equisetum species, a molecular clock calibrated with multiple fossils places the node at which the outgroup and Equisetum diverged at 343 Mya (Early Carboniferous), with the first major split among extant species occurring 170 Mya (Middle Jurassic). These dates are older than those reported in some other recent molecular clock studies but are largely in agreement with a timeline established by fossil appearance in the geological record. Representatives of evergreen subgenus Hippochaete have much larger genome sizes than those of deciduous subgenus Equisetum, despite their shared conserved chromosome number. Subgenus Paramochaete has an intermediate genome size and maintains the same number of chromosomes. CONCLUSIONS: The first divergences among extant members of the genus coincided with the break-up of Pangaea and the resulting more humid, warmer climate. Subsequent tectonic activity most likely involved vicariance events that led to species divergences combined with some more recent, long-distance dispersal events. We hypothesize that differences in genome size between subgenera may be related to the number of sperm flagellae.


Assuntos
Equisetum , Traqueófitas , Equisetum/genética , Evolução Molecular , Fósseis , Tamanho do Genoma , Filogenia
4.
Molecules ; 26(2)2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33466999

RESUMO

Equisetum myriochaetum is a semi-aquatic plant found on riverbanks that is commonly used in traditional medicine as a diuretic agent. Additionally, the genus Equisetum stands out for its content of the flavonoid kaempferol, a well-known antiproliferative agent. Therefore, in this study, E. myriochaetum ethanolic extract was tested in vitro against a cervical cancer cell line (SiHa). Additionally, the antioxidative activity was evaluated through a 2,2-diphenyl-1-picrilhidrazil (DPPH) assay. Finally, a molecular docking analysis of apigenin, kaempferol, and quercetin on the active site of ß-tubulin was performed to investigate their potential mechanism of action. All fractions of E. myriochaetum ethanolic extract showed antioxidative activity. Fraction 14 displayed an antiproliferative capacity with a half maximal inhibitory concentration (IC50) value of 6.78 µg/mL against SiHa cells.


Assuntos
Antioxidantes , Apigenina , Proliferação de Células/efeitos dos fármacos , Equisetum/química , Quempferóis , Simulação de Acoplamento Molecular , Proteínas de Neoplasias/química , Extratos Vegetais , Quercetina , Tubulina (Proteína)/química , Neoplasias do Colo do Útero , Antioxidantes/química , Antioxidantes/farmacologia , Apigenina/química , Apigenina/farmacologia , Linhagem Celular Tumoral , Etanol/química , Feminino , Humanos , Quempferóis/química , Quempferóis/farmacologia , Proteínas de Neoplasias/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Quercetina/química , Quercetina/farmacologia , Tubulina (Proteína)/metabolismo , Neoplasias do Colo do Útero/química , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
5.
Odontology ; 109(2): 464-473, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33141307

RESUMO

Periodontal disease is the most prevalent infectious disease, and inflammatory mediators play critical roles in its progression. Therefore, controlling pro-inflammatory cytokine production, especially at initial disease stages, is essential to maintaining gingival and periodontal health. Glycyrrhizin (GL) has an anti-inflammatory effect and has been added to toothpaste and mouth rinse to prevent periodontal disease. However, there is a maximum dose for the use of GL. The aim of the present study is to screen plant extracts which can effectively enhance the effects of GL. The effects of extracts from six different plants on GL-suppressed TNF-α expression in Aggregatibacter actinomycetemcomitans (A.a.)-LPS-stimulated human oral keratinocytes (RT7) were examined. Results demonstrated that Equisetum arvense (EA) extract had the strongest additive effect on the suppression of TNF-α by GL at both mRNA and protein levels. In addition, GL downregulated the production of TNF-α by suppressing NF-κB p65 phosphorylation, but not JNK or p38 phosphorylation. In contrast, EA decreased JNK phosphorylation but not NF-κB p65 or p38 phosphorylation. The combination of GL and EA effectively attenuated A.a.-LPS-induced phosphorylation of NF-κB p65 and JNK. Furthermore, an LPS-induced periodontitis rat model showed that GL with EA supplementation significantly downregulated TNF-α mRNA in the gingival tissue. These results indicate that EA can suppress A.a.-LPS-induced pro-inflammatory cytokine production by inhibiting JNK activation and can promote the anti-inflammatory effects of GL. Our findings suggest that a combination of GL and EA may improve the development of new oral hygiene products aimed at enhancing periodontal health.


Assuntos
Equisetum , Ácido Glicirrízico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Ácido Glicirrízico/farmacologia , Ácido Glicirrízico/uso terapêutico , Inflamação , Lipopolissacarídeos , NF-kappa B/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos
6.
Food Chem ; 345: 128863, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33340893

RESUMO

In vitro experiments were conducted to evaluate the effectiveness of two new biosorbents (lettuce and field horsetail) in removing aflatoxin B1 (AFB1). Formosa firethorn was used as reference material. The adsorption of AFB1 (190 ng/mL) was investigated at two sorbent contents (0.5% and 0.1% w/v) and three pHs (2, 5, and 7). Batch experiments were performed at 40 °C for 2 h. Several methodologies were used to characterize the nature of the biosorbent-AFB1 interaction. In general, when using biosorbents at 0.5% w/v, AFB1 was well adsorbed by the three tested biomaterials (70 to 100%). Furthermore, with the lowest biosorbent content (0.1% w/v), significant AFB1 adsorption efficiencies were attained at pH 5 (33 to 50%). Nevertheless, at pH 7, lettuce showed the highest ability against AFB1 removal (95%). Further characterization of the AFB1-loaded biosorbents demonstrated that chemical and physical mechanisms were involved in the adsorption process.


Assuntos
Aflatoxina B1/química , Aflatoxina B1/isolamento & purificação , Carcinógenos/química , Carcinógenos/isolamento & purificação , Equisetum/química , Alface/química , Adsorção , Biodegradação Ambiental , Contaminação de Alimentos/análise
7.
Plant J ; 105(6): 1549-1565, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33314395

RESUMO

Certain transglucanases can covalently graft cellulose and mixed-linkage ß-glucan (MLG) as donor substrates onto xyloglucan as acceptor substrate and thus exhibit cellulose:xyloglucan endotransglucosylase (CXE) and MLG:xyloglucan endotransglucosylase (MXE) activities in vivo and in vitro. However, missing information on factors that stimulate or inhibit these hetero-transglucosylation reactions limits our insight into their biological functions. To explore factors that influence hetero-transglucosylation, we studied Equisetum fluviatile hetero-trans-ß-glucanase (EfHTG), which exhibits both CXE and MXE activity, exceeding its xyloglucan:xyloglucan homo-transglucosylation (XET) activity. Enzyme assays employed radiolabelled and fluorescently labelled oligomeric acceptor substrates, and were conducted in vitro and in cell walls (in situ). With whole denatured Equisetum cell walls as donor substrate, exogenous EfHTG (extracted from Equisetum or produced in Pichia) exhibited all three activities (CXE, MXE, XET) in competition with each other. Acting on pure cellulose as donor substrate, the CXE action of Pichia-produced EfHTG was up to approximately 300% increased by addition of methanol-boiled Equisetum extracts; there was no similar effect when the same enzyme acted on soluble donors (MLG or xyloglucan). The methanol-stable factor is proposed to be expansin-like, a suggestion supported by observations of pH dependence. Screening numerous low-molecular-weight compounds for hetero-transglucanase inhibition showed that cellobiose was highly effective, inhibiting the abundant endogenous CXE and MXE (but not XET) action in Equisetum internodes. Furthermore, cellobiose retarded Equisetum stem elongation, potentially owing to its effect on hetero-transglucosylation reactions. This work provides insight and tools to further study the role of cellulose hetero-transglucosylation in planta by identifying factors that govern this reaction.


Assuntos
Celulose/metabolismo , Glucanos/metabolismo , Xilanos/metabolismo , Equisetum/enzimologia , Equisetum/metabolismo , Glicosídeo Hidrolases/metabolismo , Glicosiltransferases/metabolismo , Proteínas de Plantas/metabolismo , Brotos de Planta/metabolismo
8.
Molecules ; 25(21)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143346

RESUMO

Bioassay-guided fractionation of a cytotoxic extract derived from a solid potato dextrose agar (PDA) culture of Teratosphaeria sp. AK1128, a fungal endophyte of Equisetum arvense, afforded three new naphtho-γ-pyrone dimers, teratopyrones A-C (1-3), together with five known naphtho-γ-pyrones, aurasperone B (4), aurasperone C (5), aurasperone F (6), nigerasperone A (7), and fonsecin B (8), and two known diketopiperazines, asperazine (9) and isorugulosuvine (10). The structures of 1-3 were determined on the basis of their spectroscopic data. Cytotoxicity assay revealed that nigerasperone A (7) was moderately active against the cancer cell lines PC-3M (human metastatic prostate cancer), NCI-H460 (human non-small cell lung cancer), SF-268 (human CNS glioma), and MCF-7 (human breast cancer), with IC50s ranging from 2.37 to 4.12 µM while other metabolites exhibited no cytotoxic activity up to a concentration of 5.0 µM.


Assuntos
Antineoplásicos , Ascomicetos/química , Endófitos/química , Equisetum/microbiologia , Neoplasias/tratamento farmacológico , Pironas , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Ascomicetos/metabolismo , Endófitos/metabolismo , Feminino , Humanos , Células MCF-7 , Masculino , Neoplasias/metabolismo , Neoplasias/patologia , Células PC-3 , Pironas/química , Pironas/isolamento & purificação , Pironas/farmacologia
9.
Toxins (Basel) ; 12(11)2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182457

RESUMO

Marsh horsetail (Equisetum palustre L.) is one of the most poisonous plants of wet grasslands in the northern hemisphere, which poses a major health threat to livestock. Available data on the levels of its main alkaloids are currently contradictory due to the inadequate analytical methods and the wide variation in toxicity levels reported. Here, we tested the hypothesis that the ontogenetic stage of plant development may explain a significant part of the variations in the main Equisetum-type alkaloids. Two populations of marsh horsetail were sampled over two growing seasons. The plant material was classified according to their developmental stages and subsequently the main alkaloids were determined by hydrophilic interaction liquid chromatography and high-performance liquid chromatography electrospray tandem mass spectrometry (HILIC HPLC-ESI-MS/MS) analysis. ANOVA revealed significant effects of the ontogenetic stage but not the site on the main Equisetum-type alkaloids (sum of palustrine and palustridiene) ranging from 213 to 994 mg/kg dry matter (DM). The highest alkaloid content was found in the stages of early development. Not the season itself, but the growth temperature co-influenced the alkaloid content. Our results help to resolve the seemingly contradictory information provided by previous studies on the toxicity of E. palustre and are of practical relevance for the prevention of contamination risks in wet grassland use.


Assuntos
Alcaloides/análise , Equisetum/química , Equisetum/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Modelos Lineares , Brotos de Planta/química , Brotos de Planta/crescimento & desenvolvimento , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
10.
ACS Appl Mater Interfaces ; 12(31): 35259-35265, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32640154

RESUMO

A new discovery of highly hierarchical fibrillar biogenic silica with mesoporous structure derived from the perennial plant Equisetum fluviatile was made. By removing the organic compounds through chemical and heat treatment, the biogenic silica skeleton can largely retained the original highly hierarchical structure of the plant stems. Infrared spectra, X-ray diffraction, and small-angle X-ray scattering, as well as nitrogen sorption analysis, were employed to characterize the crystalline phases, nanostructure, and porosity of the resulting material. Scanning electron microscopy and transmission electron microscopy investigation reveal that the biogenic silica are fibers with diameters of about 120-150 µm and lengths of more than a few centimeters. These fibers consist of smaller fasciculus with diameters of about 5-15 µm that are composed of three levels of particles with mass and surface fractal characteristics: primary particles on the order of 3-5 nm, secondary particles on the order of 9-12 nm, and tertiary particles on the order of 90-120 nm in size. It is also shown that the biogenic silica have mesoporous structure with an average pore size of 4-6 nm and a specific surface of 100-300 m2/g. Heat treatment at high temperature and residual K+ significantly affects the characteristics of the mesoporous structure of the biogenic silica, although it has little effect on the surface fractal structure of the secondary particles.


Assuntos
Equisetum/química , Dióxido de Silício/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
11.
J Plant Physiol ; 251: 153210, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32544741

RESUMO

Transglycanases are enzymes that remodel the primary cell wall in plants, potentially loosening and/or strengthening it. Xyloglucan endotransglucosylase (XET; EC 2.4.1.207), ubiquitous in land plants, is a homo-transglucanase activity (donor, xyloglucan; acceptor, xyloglucan) exhibited by XTH (xyloglucan endotransglucosylase/hydrolase) proteins. By contrast, hetero-trans-ß-glucanase (HTG) is the only known enzyme that is preferentially a hetero-transglucanase. Its two main hetero-transglucanase activities are MLG : xyloglucan endotransglucosylase (MXE) and cellulose : xyloglucan endotransglucosylase (CXE). HTG is highly acidic and found only in the evolutionarily isolated genus of fern-allies, Equisetum. We now report genes for three new highly acidic HTG-related XTHs in E. fluviatile (EfXTH-A, EfXTH-H and EfXTH-I). We expressed them heterologously in Pichia and tested the encoded proteins' enzymic activities to determine whether their acidity and/or their Equisetum-specific sequences might confer high hetero-transglucanase activity. Untransformed Pichia was found to secrete MLG-degrading enzyme(s), which had to be removed for reliable MXE assays. All three acidic EfXTHs exhibited very predominantly XET activity, although low but measurable hetero-transglucanase activities (MXE and CXE) were also detected in EfXTH-H and EfXTH-I. We conclude that the extremely high hetero-transglucanase activities of Equisetum HTG are not emulated by similarly acidic Equisetum XTHs that share up to 55.5% sequence identity with HTG.


Assuntos
Equisetum/genética , Glicosiltransferases/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Equisetum/metabolismo , Glicosiltransferases/química , Glicosiltransferases/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Especificidade por Substrato
12.
Molecules ; 25(11)2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32486051

RESUMO

BACKGROUND: Equisetum arvense L., commonly known as field horsetail is a perennial fern of which extracts are rich sources of phenolic compounds, flavonoids, and phenolic acids. Activation of SIRT1 that was shown to be involved in well-known signal pathways of diabetic cardiomyopathy has a protective effect against oxidative stress, inflammatory processes, and apoptosis that are the basis of diseases such as obesity, diabetes mellitus, or cardiovascular diseases. The aim of our study was to evaluate the antidiabetic and cardioprotective effects of horsetail extract in streptozotocin induced diabetic rats. METHODS: Diabetes was induced by a single intraperitoneal injection of 45 mg/kg streptozotocin. In the control groups (healthy and diabetic), rats were administered with vehicle, whilst in the treated groups, animals were administered with 50, 100, or 200 mg/kg horsetail extract, respectively, for six weeks. Blood glucose levels, glucose tolerance, and insulin sensitivity were determined, and SIRT1 levels were measured from the cardiac muscle. RESULTS: The horsetail extract showed moderate beneficial changes in blood glucose levels and exhibited a tendency to elevate SIRT1 levels in cardiomyocytes, furthermore a 100 mg/kg dose also improved insulin sensitivity. CONCLUSIONS: Altogether our results suggest that horsetail extract might have potential in ameliorating manifested cardiomyopathy acting on SIRT1.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Cardiomiopatias Diabéticas/tratamento farmacológico , Equisetum/química , Insulina/metabolismo , Extratos Vegetais/uso terapêutico , Sirtuína 1/metabolismo , Adiposidade , Alcaloides/química , Animais , Glicemia/análise , Peso Corporal , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus Experimental/induzido quimicamente , Teste de Tolerância a Glucose , Inflamação , Injeções Intraperitoneais , Resistência à Insulina , Masculino , Miócitos Cardíacos/metabolismo , Tamanho do Órgão , Estresse Oxidativo , Fenol , Ratos , Ratos Wistar , Estreptozocina
13.
J Ethnopharmacol ; 260: 112898, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32437835

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Equisetum giganteum has been traditionally used as an anti-diabetic herbal remedy to treat diabetes in the southern state of Rio Grande do Sul in Brazil. AIM OF THE STUDY: Considering the ethonopharmacology and historical importance of E. giganteum, its potential antidiabetic effect was evaluated in alloxan induced diabetic rabbits. MATERIAL AND METHODS: Samples of Equisetum giganteum were collected in the city of Ouro Preto, Minas Gerais, Brazil. Butanolic and aqueous extracts were prepared and subsequently evaluated for anti-diabetic properties in vivo using albino male rabbits. At the end of the treatment period, the animals were euthanized, and histopathological analysis were carried out. The following biochemical parameters were studied: glucose, triacylglycerol, cholesterol, albumin, creatinine, glycosylated hemoglobin and lipase. The phytochemical profile of the extracts was studied by liquid chromatography techniques coupled to a UV/VIS detector and high-resolution mass spectrometry. RESULTS: Both aqueous and butanolic extracts were capable of reducing significantly the levels of glucose, cholesterol and triacylglycerol and thus demonstrating their hypolipidemic and hypoglycemiant effects. Furthermore, the extracts prevented the occurrence of hepatic complications during treatment. The phytochemical profile of the extracts was investigated, and the natural products detected were in agreement with those that had been previously described in the literature. CONCLUSION: Based on the significant reductions in biochemical parameters and the histologic evidence for the absence of complications in the liver, pancreas of the treated animals, Equisetum giganteum can be a therapeutically relevant resource in the treatment of diabetes and hyperlipidemia.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Equisetum , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Aloxano , Animais , Biomarcadores/sangue , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/patologia , Equisetum/química , Hemoglobina A Glicada/metabolismo , Hipoglicemiantes/isolamento & purificação , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Extratos Vegetais/isolamento & purificação , Coelhos
14.
Mol Plant ; 13(7): 1047-1062, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32376294

RESUMO

Current cell-wall models assume no covalent bonding between cellulose and hemicelluloses such as xyloglucan or mixed-linkage ß-d-glucan (MLG). However, Equisetum hetero-trans-ß-glucanase (HTG) grafts cellulose onto xyloglucan oligosaccharides (XGOs) - and, we now show, xyloglucan polysaccharide - in vitro, thus exhibiting CXE (cellulose:xyloglucan endotransglucosylase) activity. In addition, HTG also catalyzes MLG-to-XGO bonding (MXE activity). In this study, we explored the CXE action of HTG in native plant cell walls and tested whether expansin exposes cellulose to HTG by disrupting hydrogen bonds. To quantify and visualize CXE and MXE action, we assayed the sequential release of HTG products from cell walls pre-labeled with substrate mimics. We demonstrated covalent cellulose-xyloglucan bonding in plant cell walls and showed that CXE and MXE action was up to 15% and 60% of total transglucanase action, respectively, and peaked in aging, strengthening tissues: CXE in xylem and cells bordering intercellular canals and MXE in sclerenchyma. Recombinant bacterial expansin (EXLX1) strongly augmented CXE activity in vitro. CXE and MXE action in living Equisetum structural tissues potentially strengthens stems, while expansin might augment the HTG-catalyzed CXE reaction, thereby allowing efficient CXE action in muro. Our methods will enable surveys for comparable reactions throughout the plant kingdom. Furthermore, engineering similar hetero-polymer formation into angiosperm crop plants may improve certain agronomic traits such as lodging tolerance.


Assuntos
Parede Celular/metabolismo , Celulose/metabolismo , Equisetum/metabolismo , Glucanos/metabolismo , Glicosídeo Hidrolases/metabolismo , Proteínas de Plantas/metabolismo , Xilanos/metabolismo , Equisetum/enzimologia , Glicosiltransferases/metabolismo , Ligação de Hidrogênio
15.
Zootaxa ; 4718(3): zootaxa.4718.3.4, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-32230028

RESUMO

Scouring-rushes (Equisetum sg. Hippochaete) are a group of horsetails with perennial aerial shoots strongly encrusted in silica. Accordingly, they seem to resist attacks from most herbivorous insects. Michelsen (2008) speculated that larval development of the European Pegomya terminalis (Rondani) and related anthomyiids takes place in specific scouring-rushes. Presently, we document that the larvae of two North American species related to P. terminalis attack developing shoots of Common scouring-rush, Equisetum hyemale L. Both species, Pegomya disticha Griffiths and P. cedrica Huckett, were found to coexist in a population of scouring-rush in Oklahoma. Various aspects of the life-history and morphology (3rd instar larva, male and female adults) for both species are described and documented by photos.


Assuntos
Dípteros , Equisetum , Animais , Feminino , Larva , Masculino , Dióxido de Silício
16.
J Formos Med Assoc ; 119(12): 1835-1841, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32192793

RESUMO

BACKGROUND/PURPOSE: One effective way to deal with dentin hypersensitivity is to develop materials to seal the tubules. The porous bio-calcium carbonate-silica (BCCS) contained well-dispersed CaCO3 would form calcium phosphates to seal the dentinal tubules when mixed with an acidic solution. The acidic hydrothermal treatment and calcination to isolate the BCCS from the agricultural waste like equisetum grass was used, which would be more environmentally friendly than chemically synthesized mesoporous biomaterials. The aim of this study was to develop mesoporous materials from natural resources to occlude the dentinal tubules which could be more environmentally-friendly. METHODS: Dentin disc samples were prepared and treated with different methods as follows: (1) BCCS mixed with H3PO4; (2) BCCS mixed with KH2PO4; (3) Seal & Protect® was used as a comparison group. Sealing efficacy was evaluated by measuring the depths and percentages of precipitate occlusion in dentinal tubules with SEM. RESULTS: The N2 adsorption-desorption isotherm of the BCCS demonstrated a pore size of around 15.0 nm and a surface area of 61 m2g-1. From the results of occlusion percentage and depth, the BCCS treated with H3PO4 or KH2PO4 demonstrated promising sealing efficacy than the commercial product. CONCLUSION: This synthetic process used the agricultural waste equisetum grass to produce bio-calcium carbonate-silica would be environmentally friendly, which has great potential in treating exposed dentin related diseases.


Assuntos
Equisetum , Carbonato de Cálcio , Cristalização , Dentina , Sensibilidade da Dentina , Humanos , Microscopia Eletrônica de Varredura , Poaceae , Dióxido de Silício
17.
Am J Bot ; 107(3): 477-488, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32107771

RESUMO

PREMISE: Perhaps the most rapid period of vascular plant evolution occurred during the Silurian-Devonian time interval. Yet, few quantitative analyses have established the extent to which anatomical, morphological, or reproductive features contributed to this episode of tracheophyte diversification. METHODS: Phylogenetic analyses were performed using a newly revised matrix of 54 characters (with 158 character states) of 37 of the best-preserved Paleozoic (predominantly Devonian) plants. Equisetum was included to determine whether it aligns with fossil sphenopsids or taxa collectively considered "ferns". The topology of the 54-character consensus tree was then compared to the topologies generated using only reproductive features (18 characters; 47 character states), only anatomical features (14 characters; 54 character states), only morphological features (22 characters; 57 character states), and the three pairwise combinations (e.g., anatomical and morphological characters). RESULTS: The new 54-character tree topology continued to identify a trimerophyte-euphyllophyte clade and a zosterophyllophyte-lycophyte clade emerging from a Cooksonia-rhyniophyte plexus. Equisetum aligned with fossil sphenopsids rather than fern-like fossil taxa. Reproductive characters or anatomical characters analyzed in isolation resulted in nearly complete polytomy. Among the various permutations of the three categories, anatomical and morphological characters when combined provided the best restoration of the 54-character tree topology. CONCLUSIONS: The phylogenetic relationships among the canonical fossil taxa used in this analysis predominantly reflect morphological trends. Reproductive and anatomical features taken in isolation appear to be evolutionarily conservative characters, i.e., natural selection "sees" the external phenotype.


Assuntos
Equisetum , Gleiquênias , Fósseis , Filogenia , Reprodução
18.
Braz. j. biol ; 80(1): 12-22, Feb. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1089299

RESUMO

Abstract Medicinal plants, such as E. pyramidale, are alternatives against infections and assist in the healing process of wounds. We evaluated the effects of Hydrogel of E. pyramidale on the healing of cutaneous wounds in animal models by morphological, morphometric and histological analyses, and elucidated major components. The ethanolic extract of E. pyramidale shoots was submitted to phytochemical analysis. For cicatrizing activity assay, Wistar rats were used, and the groups evaluated were hydrogel containing ethanolic extract of E. pyramidale at 2% compared to control groups. The treatment periods were 3, 7 and 21 days, and macroscopic and microscopic analyses were performed. Data were submitted to Analysis of Variance (p <0.05). Phytochemistry and quantification evidenced that flavonoids are main constituents and that they were evidenced by thin layer chromatography (TLC), high efficiency (HPLC) and infrared (IR) methods. In TLC, using flavonoid patterns, we observed pinocembrin. The hydrogel containing ethanolic extract of E. pyramidale at 2% was effective in wound regression. E. pyramidale can be used for the treatment of second intention wounds, and the effective healing may be due to a high flavonoid content.


Resumo As plantas medicinais, como E. pyramidale, são uma alternativa para combater infecções e ajudar o processo de cicatrização de feridas. Avaliar os efeitos do hidrogel de E. pyramidale na cicatrização de feridas cutâneas em modelos animais através de análises morfológicas, morfométricas e histológicas, bem como para elucidar os principais componentes. O extrato etanólico das partes aéreas de E. pyramidale foi submetido a análise fitoquímica. Para o ensaio de atividade cicatrizante, foram utilizados ratos Wistar e os grupos avaliados foram o hidrogel com extrato etanólico de E. pyramidale 2% em comparação com os grupos controle. Os períodos de tratamento foram 3, 7 e 21 dias e as análises macroscópicas e microscópicas foram realizadas e os dados submetidos à Análise de Variância (p <0,05). A fitoquímica e a quantificação indicaram que os flavonóides são os constituintes principais e que mesmos foram evidenciados na cromatografia de camada delgada (CCD), de alta eficiência (HPLC) e por infravermelho (IV). Em CCD, empregando padrões de flavonoides, foi observado a pinocembrina. O hidrogel com extrato etanólico de E. pyramidale 2% foi eficaz na regressão da ferida. E. pyramidale pode ser usado no tratamento de feridas de segunda intenção e a cura efetiva pode ser devido ao alto teor de flavonoides.


Assuntos
Animais , Ratos , Equisetum , Pele , Extratos Vegetais , Ratos Wistar , Hidrogéis
19.
Braz J Biol ; 80(1): 12-22, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31090815

RESUMO

Medicinal plants, such as E. pyramidale, are alternatives against infections and assist in the healing process of wounds. We evaluated the effects of Hydrogel of E. pyramidale on the healing of cutaneous wounds in animal models by morphological, morphometric and histological analyses, and elucidated major components. The ethanolic extract of E. pyramidale shoots was submitted to phytochemical analysis. For cicatrizing activity assay, Wistar rats were used, and the groups evaluated were hydrogel containing ethanolic extract of E. pyramidale at 2% compared to control groups. The treatment periods were 3, 7 and 21 days, and macroscopic and microscopic analyses were performed. Data were submitted to Analysis of Variance (p <0.05). Phytochemistry and quantification evidenced that flavonoids are main constituents and that they were evidenced by thin layer chromatography (TLC), high efficiency (HPLC) and infrared (IR) methods. In TLC, using flavonoid patterns, we observed pinocembrin. The hydrogel containing ethanolic extract of E. pyramidale at 2% was effective in wound regression. E. pyramidale can be used for the treatment of second intention wounds, and the effective healing may be due to a high flavonoid content.


Assuntos
Equisetum , Animais , Hidrogéis , Extratos Vegetais , Ratos , Ratos Wistar , Pele
20.
Ann Hepatol ; 19(1): 107-112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31537508

RESUMO

Vanishing bile duct syndrome is a rare acquired condition, characterized by progressive loss of intrahepatic bile ducts leading to ductopenia and cholestasis. It can be associated with infections, ischemia, drug adverse reactions, neoplasms, autoimmune disease, and allograft rejection. Prognosis is variable and depends on the etiology of bile duct injury. We report the case of a 25-year-old female with cholestatic hepatitis and concomitant intakes of hepatotoxic substances, such as garcinia, field horsetail, and ketoprofen. On suspicion of a drug-induced liver injury, the drugs were promptly withdrawn and ursodeoxycholic acid was started with initial clinical and laboratory improvement, and the patient was discharged from the hospital. One month later, she had a new increase in bilirubin levels and canalicular enzymes, requiring a liver biopsy that showed significant loss of intrahepatic bile ducts, which was compatible with vanishing bile duct syndrome. This was confirmed by using cytokeratin 19 on immunohistochemistry. There was subsequent lymph node enlargement in several chains, and relevant weight loss. Histological analysis of a cervical lymph node revealed nodular sclerosis-subtype classic Hodgkin lymphoma. In this setting, vanishing bile duct syndrome was related to Hodgkin lymphoma and a drug-induced liver injury overlap, leading to progressive cholestasis with a worse prognosis. The patient's response to chemotherapy was poor, requiring biological therapy with brentuximab vedotin. It is crucial for physicians to create a broad differential diagnosis in suspected vanishing bile duct syndrome patients, especially to rule out malignancies.


Assuntos
Ductos Biliares Intra-Hepáticos/patologia , Doença Hepática Induzida por Substâncias e Drogas/complicações , Colestase Intra-Hepática/etiologia , Doença de Hodgkin/complicações , Fígado/patologia , Linfonodos/patologia , Adulto , Alanina Transaminase/sangue , Anti-Inflamatórios não Esteroides/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Biópsia , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Colagogos e Coleréticos/uso terapêutico , Colestase Intra-Hepática/sangue , Colestase Intra-Hepática/tratamento farmacológico , Colestase Intra-Hepática/patologia , Equisetum/efeitos adversos , Feminino , Garcinia/efeitos adversos , Gastrite/etiologia , Hematemese/etiologia , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/patologia , Humanos , Cetoprofeno/efeitos adversos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia Computadorizada por Raios X , Ácido Ursodesoxicólico/uso terapêutico
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