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1.
Mar Drugs ; 19(10)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34677456

RESUMO

Fucoidans are algal polysaccharides that exhibit protective properties against oxidative stress. The aim of this study was to investigate different fucoidans from brown seaweeds for their ability to protect against iron-dependent oxidative stress (ferroptosis), a main hallmark of retinal and brain diseases, including hemorrhage. We investigated five new high-molecular weight fucoidan extracts from Fucus vesiculosus, F. serratus, and F. distichus subsp. evanescens, a previously published Laminaria hyperborean extract, and commercially available extracts from F. vesiculosus and Undaria pinnatifida. We induced oxidative stress by glutathione depletion (erastin) and H2O2 in four retinal and neuronal cell lines as well as primary cortical neurons. Only extracts from F. serratus, F. distichus subsp. evanescens, and Laminaria hyperborea were partially protective against erastin-induced cell death in ARPE-19 and OMM-1 cells, while none of the extracts showed beneficial effects in neuronal cells. Protective fucoidans also attenuated the decrease in protein levels of the antioxidant enzyme GPX4, a key regulator of ferroptosis. This comprehensive analysis demonstrates that the antioxidant abilities of fucoidans may be cell type-specific, besides depending on the algal species and extraction method. Future studies are needed to further characterize the health-benefiting effects of fucoidans and to determine the exact mechanism underlying their antioxidative abilities.


Assuntos
Antioxidantes/farmacologia , Fucus , Laminaria , Polissacarídeos/farmacologia , Organismos Aquáticos , Morte Celular/efeitos dos fármacos , Linhagem Celular/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio , Ferro , Neurônios , Estresse Oxidativo/efeitos dos fármacos , Retina
2.
Mar Drugs ; 19(4)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805470

RESUMO

Fucoidans, sulfated polysaccharides extracted from brown algae, are marine products with the potential to modulate bone formation and vascularization processes. The bioactivity and safety of fucoidans are highly associated with their chemical structure, which may vary with algae species and extraction method. Thus, in depth evaluation of fucoidan extracts in terms of endotoxin content, cytotoxicity, and their detailed molecular biological impact on the individual cell types in bone is needed. In this study, we characterized fucoidan extracts from three different Fucus species including Fucus vesiculosus (Fv), Fucus serratus (Fs), and Fucus distichus subsp. evanescens (Fe) for their chemical features, endotoxin content, cytotoxicity, and bioactive effects on human outgrowth endothelial cells (OEC) and human mesenchymal stem cells (MSC) as in vitro models for bone function and vascularization. Extracts contained mainly high molecular weight (HMW) fucoidans and were free of endotoxins that may cause inflammation or influence vascularization. OEC tolerated fucoidan concentrations up to 200 µg/mL, and no indication of cytotoxicity was observed. The inflammatory response, however, investigated by real-time PCR (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) and endothelial barrier assessed by impedance measurement differed for the individual extracts. MSC in comparison with endothelial cells were more sensitive to fucoidans and showed partly reduced metabolic activity and proliferation at higher doses of fucoidans. Further results for MSC indicated impaired osteogenic functions in alkaline phosphatase and calcification assays. All tested extracts consistently lowered important molecular mediators involved in angiogenesis, such a VEGF (vascular endothelial growth factor), ANG-1 (angiopoietin 1), and ANG-2 (angiopoietin 2), as indicated by RT-PCR and ELISA. This was associated with antiangiogenic effects at the functional level using selected extracts in co-culture models to mimic bone vascularization processes during bone regeneration or osteosarcoma.


Assuntos
Inibidores da Angiogênese/farmacologia , Células Endoteliais/efeitos dos fármacos , Fucus/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Polissacarídeos/farmacologia , Inibidores da Angiogênese/isolamento & purificação , Proteínas Angiogênicas/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Células Endoteliais/metabolismo , Metabolismo Energético/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Células-Tronco Mesenquimais/metabolismo , Peso Molecular , Polissacarídeos/isolamento & purificação , Transdução de Sinais
3.
Mol Pharm ; 16(11): 4636-4650, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31560549

RESUMO

In drug development, estimating fraction absorbed (Fa) in man for permeability-limited compounds is important but challenging. To model Fa of such compounds from apparent permeabilities (Papp) across filter-grown Caco-2 cell monolayers, it is central to elucidate the intestinal permeation mechanism(s) of the compound. The present study aims to refine a computational permeability model to investigate the relative contribution of paracellular and transcellular routes to the Papp across Caco-2 monolayers of the permeability-limited compound acamprosate having a bioavailability of ∼11%. The Papp values of acamprosate and of several paracellular marker molecules were measured. These Papp values were used to refine system-specific parameters of the Caco-2 monolayers, that is, paracellular pore radius, pore capacity, and potential drop. The refined parameters were subsequently used as an input in modeling the permeability (Pmodeled) of the tested compounds using mathematical models collected from two published permeability models. The experimental data show that acamprosate Papp across Caco-2 monolayers is low and similar in both transport directions. The obtained acamprosate Papp, 1.56 ± 0.28 × 10-7 cm·s-1, is similar to the Papp of molecular markers for paracellular permeability, namely, mannitol (2.72 ± 0.24 × 10-7 cm·s-1), lucifer yellow (1.80 ± 0.35 × 10-7 cm·s-1), and fluorescein (2.10 ± 0.28 × 10-7 cm·s-1), and lower than that of atenolol (7.32 ± 0.60 × 10-7 cm·s-1; mean ± SEM, n = 3-6), while the end-point amount of acamprosate internalized by the cell monolayer, Qmonolayer, was lower than that of mannitol. Acamprosate did not influence the barrier function of the monolayers since it altered neither the Papp of the three paracellular markers nor the transepithelial electrical resistance (TEER) of the cell monolayer. The Pmodeled for all the paracellular markers and acamprosate was dominated by the Ppara component and matched the experimentally obtained Papp. Furthermore, acamprosate did not inhibit the uptake of probe substrates for solute carriers PEPT1, TAUT, PAT1, EAAT1, B0,+AT/rBAT, OATP2B1, and ASBT expressed in Caco-2 cells. Thus, the Pmodeled estimated well Ppara, and the paracellular route appears to be the predominant mechanism for acamprosate Papp across Caco-2 monolayers, while the alternative transcellular routes, mediated by passive diffusion or carriers, are suggested to only play insignificant roles.


Assuntos
Acamprosato/metabolismo , Atenolol/metabolismo , Disponibilidade Biológica , Transporte Biológico/fisiologia , Células CACO-2 , Linhagem Celular Tumoral , Difusão , Fluoresceína/metabolismo , Humanos , Isoquinolinas/metabolismo , Manitol/metabolismo , Permeabilidade
4.
Physiol Plant ; 154(2): 314-27, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25302638

RESUMO

We examined the effect of light emitting diode (LED) lighting in greenhouse facilities on growth, chlorophyll fluorescence and pigmentation in Phalaenopsis 'Vivien' and 'Purple Star' under purpose-built LED arrays yielding c. 200 µmol m(-2) s(-1) at plant height for 14 h per day and 24/18°C day/night temperature, respectively, from January to April 2013. The light treatments were (1) 40% blue in 60% red (40% B/R), (2) 0% blue in 100% red (0% B/R) and (3) white LEDs with 32% blue in white (32% B/W, control), with background daylight under shade screens. The plants were harvested twice for leaf growth and pigmentation. There was no clear pattern in the spectral effect on growth since the order of leaf size differed between harvests in March and April. Fv /Fm was in the range of 0.52-0.72, but overall slightly higher in the control, which indicated a permanent downregulation of PSII in the colored treatments. The fluorescence quenching showed no acclimation to color in 'Purple Star', while 'Vivien' had lower ETR and higher NPQ in the 40% B/R, resembling low light acclimation. The pigmentation showed corresponding spectral response with increasing concentration of lutein while increasing the fraction of blue light, which increased the light absorption in the green/yellow part of the spectrum. The permanent downregulation of PSII moved a substantial part of the thermal dissipation from the light regulated NPQ to non-regulated energy losses estimated by ΦNPQ and ΦNO and the difference found in the balance between ΦPSII and ΦNPQ in 'Vivien' disappeared when ΦNO was included in the thermal dissipation.


Assuntos
Clorofila/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Orchidaceae/efeitos da radiação , Pigmentação/efeitos da radiação , Aclimatação , Fluorescência , Luz , Orchidaceae/fisiologia , Fotossíntese/efeitos da radiação , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Temperatura
5.
J Nat Prod ; 78(8): 1877-85, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26218649

RESUMO

A detailed phytochemical investigation of a dichloromethane extract of the resinous exudates of the cushion bush plant (Leucophyta brownii) resulted in the isolation of the new 8,12-guaianolides leucophytalins A (5) and B (6), the new 1,10-seco-eudesmane leucophytalin C (10), six rare 8,12-guaianolides (1-4, 7, and 8), and the xanthanolide tomentosin (9). The structures of all isolated compounds were elucidated on the basis of spectroscopic and spectrometric analyses. The structures of compounds isolated in crystalline form, including leucophytalins A and C, were further confirmed by X-ray crystallography. The crude extract exhibited moderate cytostatic activity against a breast cancer (MCF-7) and human colon cancer (HT-29) cell line with IC50 values of 9.3 and 18 µg/mL, respectively, and anti-inflammatory activity against the macrophage-like cell line RAW 264.7 with IC50 values of 3.9 and 6.1 µg/mL for thromboxane B2 and prostaglandin E2 production, respectively. The isolated compounds were evaluated for their cytostatic activity against MCF-7 and HT-29 cells (1, 3-10) and their anti-inflammatory activity against RAW 264.7 cells (1-10). All isolated compounds are most likely derived from (+)-germacrene A, and a biosynthetic pathway is proposed for these sesquiterpenoids.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Asteraceae/química , Citostáticos/isolamento & purificação , Citostáticos/farmacologia , Sesquiterpenos de Eudesmano/isolamento & purificação , Sesquiterpenos de Eudesmano/farmacologia , Sesquiterpenos de Guaiano/isolamento & purificação , Sesquiterpenos de Guaiano/farmacologia , Animais , Anti-Inflamatórios/química , Cristalografia por Raios X , Citostáticos/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Lactonas/química , Camundongos , Estrutura Molecular , Resinas Vegetais/química , Sesquiterpenos/química , Sesquiterpenos de Eudesmano/química , Sesquiterpenos de Guaiano/química
6.
Planta Med ; 80(18): 1712-20, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25371981

RESUMO

Echinacea purpurea has been used in traditional medicine as a remedy for the treatment and prevention of upper respiratory tract infections and the common cold. Recent investigations have indicated that E. purpurea also has an effect on insulin resistance. A dichloromethane extract of E. purpurea roots was found to enhance glucose uptake in adipocytes and to activate peroxisome proliferator-activated receptor γ. The purpose of the present study was to identify the bioactive compounds responsible for the potential antidiabetic effect of the dichloromethane extract using a bioassay-guided fractionation approach. Basal and insulin-dependent glucose uptake in 3T3-L1 adipocytes were used to assess the bioactivity of extract, fractions and isolated metabolites. A peroxisome proliferator-activated receptor γ transactivation assay was used to determine the peroxisome proliferator-activated receptor γ activating properties of the extract, active fractions and isolated metabolites. Two novel isomeric dodeca-2E,4E,8Z,10E/Z-tetraenoic acid 2-methylbutylamides together with two known C12-alkamides and α-linolenic acid were isolated from the active fractions. The isomeric C12-alkamides were found to activate peroxisome proliferator-activated receptor γ, to increase basal and insulin-dependent glucose uptake in adipocytes in a dose-dependent manner, and to exhibit characteristics of a peroxisome proliferator-activated receptor γ partial agonist.


Assuntos
Echinacea/química , Glucose/metabolismo , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Células 3T3-L1/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Hipoglicemiantes/química , Insulina/metabolismo , Insulina/farmacologia , Espectroscopia de Ressonância Magnética , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , PPAR gama/agonistas , PPAR gama/genética , PPAR gama/metabolismo , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Plantas Medicinais/química , Alcamidas Poli-Insaturadas/química
7.
Contact Dermatitis ; 70(2): 98-103, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24102077

RESUMO

BACKGROUND: Immediate hypersensitivity reactions to root vegetables of the Umbelliferae plant family (Apiaceae) is well known. Delayed-type hypersensitivity is rarely reported. OBJECTIVE: To report the first case of systemic contact dermatitis caused by root vegetables and some chemical implications. MATERIALS AND METHODS: Prick and patch testing were performed with fresh vegetables and selected allergens, and this was followed by high-performance liquid chromatography-mass spectrometry (MS)/MS analysis of the falcarinol syringe. RESULTS: The patient was contact-sensitive to celeriac, parsnip, and carrot, but tested negative to falcarinol. Subsequent analysis showed that the syringe contained falcarinol. CONCLUSION: The non-occupational sensitization resulting from both direct and systemic contact with Apiaceae root vegetables was apparently not caused by falcarinol.


Assuntos
Dermatite Alérgica de Contato/etiologia , Hipersensibilidade Alimentar/etiologia , Verduras/efeitos adversos , Adulto , Apium/efeitos adversos , Conjuntivite/etiologia , Daucus carota/efeitos adversos , Di-Inos/efeitos adversos , Álcoois Graxos/efeitos adversos , Feminino , Dermatoses da Mão/induzido quimicamente , Dermatoses da Mão/etiologia , Humanos , Pastinaca/efeitos adversos , Testes do Emplastro , Rinite/etiologia , Estomatite/etiologia
8.
Planta ; 237(4): 955-66, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23179446

RESUMO

The concentration of the lifesaving antimalarial compound artemisinin (AN) in cultivated Artemisia annua (A. annua) plants is relatively low, and thus research in improving the content is important. In the present study, external stress was applied to adult plants of A. annua and the effect was examined on the concentrations of AN and its immediate precursors in leaves, and these concentrations were related to densities and sizes of the glandular trichomes (GT). Plants were stress treated weekly five times by sandblasting or spraying with salicylic acid, chitosan oligosaccharide, H2O2, and NaCl solutions. Contents of AN-related compounds (AN-c) were analysed in leaf samples from an upper and a lower position of the plants, and GT were quantified and measured. In lower leaves, several stress treatments had significant negative effects on concentrations of AN-c, whereas the ratios between compounds showed an increased conversion to AN. In the upper leaves, no changes were observed compared to controls. Linear relations were found between the concentrations of metabolites and the density of GT in both upper and lower leaves, and size of GT in lower leaves. Results suggested that older and younger leaves may respond differently to applied stress. A part of the plants were infected by powdery mildew, and this caused significantly different compositions of the AN-c, compared to uninfected plants. In conclusion, changes in concentrations of AN-c seemed largely to be related to changes in GT densities and sizes.


Assuntos
Artemisia annua/metabolismo , Artemisininas/metabolismo , Estresse Fisiológico , Artemisia annua/microbiologia , Ascomicetos/fisiologia , Interações Hospedeiro-Patógeno
9.
Plant Physiol ; 157(4): 2194-205, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22021421

RESUMO

Application of 3.6 mm silicon (Si+) to the rose (Rosa hybrida) cultivar Smart increased the concentration of antimicrobial phenolic acids and flavonoids in response to infection by rose powdery mildew (Podosphaera pannosa). Simultaneously, the expression of genes coding for key enzymes in the phenylpropanoid pathway (phenylalanine ammonia lyase, cinnamyl alcohol dehydrogenase, and chalcone synthase) was up-regulated. The increase in phenolic compounds correlated with a 46% reduction in disease severity compared with inoculated leaves without Si application (Si-). Furthermore, Si application without pathogen inoculation induced gene expression and primed the accumulation of several phenolics compared with the uninoculated Si- control. Chlorogenic acid was the phenolic acid detected in the highest concentration, with an increase of more than 80% in Si+ inoculated compared with Si- uninoculated plants. Among the quantified flavonoids, rutin and quercitrin were detected in the highest concentrations, and the rutin concentration increased more than 20-fold in Si+ inoculated compared with Si- uninoculated plants. Both rutin and chlorogenic acid had antimicrobial effects on P. pannosa, evidenced by reduced conidial germination and appressorium formation of the pathogen, both after spray application and infiltration into leaves. The application of rutin and chlorogenic acid reduced powdery mildew severity by 40% to 50%, and observation of an effect after leaf infiltration indicated that these two phenolics can be transported to the epidermal surface. In conclusion, we provide evidence that Si plays an active role in disease reduction in rose by inducing the production of antifungal phenolic metabolites as a response to powdery mildew infection.


Assuntos
Antifúngicos/metabolismo , Flavonoides/metabolismo , Hidroxibenzoatos/metabolismo , Doenças das Plantas/prevenção & controle , Rosa/efeitos dos fármacos , Silício/farmacologia , Aciltransferases/genética , Oxirredutases do Álcool/genética , Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/fisiologia , Ácido Clorogênico/metabolismo , Ácido Clorogênico/farmacologia , Flavonoides/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Interações Hospedeiro-Patógeno , Hidroxibenzoatos/farmacologia , Fenilalanina Amônia-Liase/genética , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Quercetina/análogos & derivados , Quercetina/metabolismo , Quercetina/farmacologia , Rosa/metabolismo , Rosa/microbiologia , Rutina/metabolismo , Rutina/farmacologia , Regulação para Cima
10.
Avian Pathol ; 41(4): 369-76, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22834551

RESUMO

The aerial parts of the plant Artemisia annua contain essential oils having antimicrobial properties against Clostridium perfringens Type A, the causal agent for necrotic enteritis in broilers. In two experiments, the influence of increasing dietary concentrations of dried A. annua leaves (0, 5, 10 and 20 g/kg) and n-hexane extract from fresh A. annua leaves (0, 125, 250 and 500 mg/kg) on broiler performance was investigated. Dried plant material decreased feed intake and body weight in a dose-dependent manner, and 10 and 20 g/kg diet tended to improve the feed conversion ratio. The n-hexane extract also reduced feed intake, but broiler weight tended to decrease only at the highest dietary concentration. The feed conversion ratio tended to improve when birds received 250 and 500 mg/kg n-hexane extract. In a third experiment, a necrotic enteritis disease model was applied to investigate the effect of the dietary addition of dried A. annua leaves (10 g/kg on top) or n-hexane extract of A. annua (250 mg/kg) on the severity of the disease in broilers. The addition of n-hexane extract reduced the intestinal C. perfringens numbers and the severity of the disease-related small intestinal lesions. Over the infection period from day 17 to day 27, birds supplemented with the n-hexane extract gained more weight than both the challenged control birds and birds receiving dried plant material. The results indicate that n-hexane extracts derived from A. annua can modulate the course of necrotic enteritis and compensate to a certain extent for the disease-associated weight losses.


Assuntos
Artemisia annua/química , Galinhas , Infecções por Clostridium/veterinária , Clostridium perfringens/efeitos dos fármacos , Enterite/veterinária , Doenças das Aves Domésticas/prevenção & controle , Animais , Peso Corporal , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/prevenção & controle , Clostridium perfringens/crescimento & desenvolvimento , Contagem de Colônia Microbiana/veterinária , Dieta/veterinária , Relação Dose-Resposta a Droga , Enterite/tratamento farmacológico , Enterite/microbiologia , Enterite/prevenção & controle , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Masculino , Testes de Sensibilidade Microbiana/veterinária , Microbiota/efeitos dos fármacos , Necrose , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/microbiologia , Aumento de Peso , Redução de Peso
11.
J Sci Food Agric ; 92(14): 2891-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22337263

RESUMO

BACKGROUND: The aim of the present work was to study to what extent grazing large amounts of white clover (WCL), red clover (RCL), lucerne (LUC) or chicory (CHI) was suitable for production of bovine milk with a high milk fat content of tocopherols, carotenoids, α-linolenic acid and conjugated linoleic acid. RESULTS: WCL, RCL, LUC and CHI swards were established to investigate the influence of herbage composition on the milk quality of grazing dairy cows at three periods. Average milk fat composition showed high concentrations of linolenic acid (12 mg g⁻¹), conjugated linoleic acid (13 mg g⁻¹), carotenoids (6 µg g⁻¹) and α-tocopherol (21 µg g⁻¹ milk fat). There were minor differences between herbage types and periods, but multivariate analysis of these data showed no clear grouping. Chemical composition of herbage varied with species as well as period, but it was not possible to relate milk and feed contents of specific fatty acids, carotenoids or tocopherols. CONCLUSION: All four herbages tested were suitable for production of milk with a high content of beneficial compounds. Thus any of these herbages could be used in production of such differentiated milk based on a large proportion of grazing in the ration.


Assuntos
Carotenoides/análise , Bovinos/crescimento & desenvolvimento , Indústria de Laticínios/métodos , Ácidos Graxos Insaturados/análise , Alimentos Orgânicos/análise , Leite/química , Tocoferóis/análise , Animais , Animais Endogâmicos , Carotenoides/metabolismo , Bovinos/metabolismo , Cichorium intybus/química , Cichorium intybus/crescimento & desenvolvimento , Cichorium intybus/metabolismo , Dinamarca , Ácidos Graxos Insaturados/metabolismo , Feminino , Qualidade dos Alimentos , Lactação , Ácidos Linoleicos Conjugados/análise , Ácidos Linoleicos Conjugados/metabolismo , Medicago sativa/química , Medicago sativa/crescimento & desenvolvimento , Medicago sativa/metabolismo , Leite/metabolismo , Análise de Componente Principal , Estações do Ano , Tocoferóis/metabolismo , Trifolium/química , Trifolium/crescimento & desenvolvimento , Trifolium/metabolismo , Ácido alfa-Linolênico/análise , Ácido alfa-Linolênico/metabolismo
12.
J Biomed Mater Res A ; 110(4): 861-872, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34792851

RESUMO

The need for a substitute for allograft and autograft is rising as bone graft surgeries exceed available supplies. We investigated the efficacy of the low-molecular weight marine bioactive compound fucoidan (FUC) on bone regeneration and implant fixation in seven female sheep, as FUC has shown great promise as a bone substitute. Titanium implants were inserted bilaterally in the distal femurs to test three hydroxyapatite/fucoidan (HA/FUC) groups and compared to allograft. The HA was coated with either 500 or 1500 µg of FUC, obtained by microwave-assisted chemical extraction, or 500 µg of FUC obtained by an enzyme-assisted extraction method. The concentric 2-mm gap around the implant was filled with either one of the HA/FUCs or allograft from the donor sheep. After 12 weeks, implant-bone blocks were harvested and divided into three parts for mechanical push-out testing, immunohistochemistry, and micro-CT and histomorphometry. Pronounced bone formations were observed by micro-CT and histomorphometry in all groups, but higher bone volume fractions were seen in the allograft group compared to the three HA/FUC groups. The trabecular thickness, trabecular separation, and architectural anisotropy were all significantly higher in the allograft group compared to the three HA/FUC groups. In conclusion, adequate bone formation was observed in all groups, although the bone formation was significantly greater in the allograft group. Also, no significant differences existed in the shear mechanical properties between groups, suggesting that the combination of HA and FUC can achieve a similar fixation strength to allograft in this model.


Assuntos
Substitutos Ósseos , Animais , Regeneração Óssea , Substitutos Ósseos/química , Durapatita/química , Feminino , Osseointegração , Polissacarídeos , Próteses e Implantes , Ovinos , Titânio
13.
J Comput Aided Mol Des ; 25(2): 107-16, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21069556

RESUMO

In a search for more effective and safe anti-diabetic compounds, we developed a pharmacophore model based on partial agonists of PPARγ. The model was used for the virtual screening of the Chinese Natural Product Database (CNPD), a library of plant-derived natural products primarily used in folk medicine. From the resulting hits, we selected methyl oleanonate, a compound found, among others, in Pistacia lentiscus var. Chia oleoresin (Chios mastic gum). The acid of methyl oleanonate, oleanonic acid, was identified as a PPARγ agonist through bioassay-guided chromatographic fractionations of Chios mastic gum fractions, whereas some other sub-fractions exhibited also biological activity towards PPARγ. The results from the present work are two-fold: on the one hand we demonstrate that the pharmacophore model we developed is able to select novel ligand scaffolds that act as PPARγ agonists; while at the same time it manifests that natural products are highly relevant for use in virtual screening-based drug discovery.


Assuntos
Hipoglicemiantes/análise , PPAR gama/agonistas , PPAR gama/análise , Pistacia/química , Extratos Vegetais/química , Triterpenos/química , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Descoberta de Drogas/métodos , Fibroblastos , Hipoglicemiantes/química , Camundongos , PPAR gama/química , Extratos Vegetais/análise , Triterpenos/análise
14.
Plant Methods ; 17(1): 130, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930361

RESUMO

BACKGROUND: Fucoidans are sulfated polysaccharides from the cell-wall of brown algae. They have a wide range of applications in medicine, including regenerative medicine, ophthalmology, cancer, and autoimmune disease. Biological activity of fucoidans directly depends on their structure, which remains poorly understood. This is primarily because the polymeric nature of these molecules limits the use of nuclear magnetic resonance and mass spectrometry, classical tools of structural biology for their structural characterization. Raman and Infrared spectroscopies are non-invasive and non-destructive techniques that can be used to probe the structural organization of biological specimens. In this study, we investigate the potential of Raman and Infrared spectroscopy for structural analysis of several fucoidan extracts. RESULTS: Our results show that Infrared and Raman provide different but complimentary information about the structure of crude extracts of fucoidans, revealing the presence of minor impurities from co-extractants. We also found that at high extraction temperatures acidic conditions limit formation of melanoidins, while also yielding relatively high sulfate ester fucoidan. However, at high temperatures, water extraction may potentially result in formation of advanced glycation end products. Their presence could be problematic for fucoidan extracts intended for medicinal use, as advanced glycation end products have been linked to endocrine interruption mechanisms in vivo by crosslinking to and permanently altering extracellular matrix proteins. CONCLUSION: Raman and Infrared can be used as complementary tools for rapid screening of crude fucoidan extracts, which can be a valuable tool for assessing impurities that remain after extraction.

15.
Nutrients ; 13(6)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073610

RESUMO

Vegetables rich in bitter-tasting phytochemicals may exert enhanced beneficial effects against key factors associated with type two diabetes (T2D). This study investigates whether selected cultivars of bitter and strong-tasting (BST) Brassica and root vegetables exert greater health benefits on T2D patients compared to equivalent modern mild and sweet tasting (MST) vegetables. A 12-week randomized, controlled, parallel intervention study involved 92 T2D patients, who were allocated three different diets: (1) 500 g daily of bitter and strong-tasting (BST) vegetables; (2) 500 g daily of mild and sweet-tasting (MST) vegetables; (3) 120 g daily MST normal diet (control). Both vegetable diets contained root vegetables and cabbages selected based on sensory differences and content of phytochemicals. Prior to and after the study, all participants underwent an oral glucose tolerance test (OGTT), 24 h blood pressure measurements, DEXA scans, and fasted blood samples. Both diets high in vegetables significantly reduced the participants' BMI, total body fat mass, and HbA1c levels compared to control, but in the BST group, significant differences were also found regarding incremental area under the curve glucose 240 min (OGTT) and fasting glucose levels. A high daily intake of root vegetables and cabbages showed significant health improvements in both vegetable groups. BST vegetables had the greatest impact on insulin sensitivity, body fat mass, and blood pressure compared to control; moreover, they further improved glycemic control compared to MST vegetables.


Assuntos
Diabetes Mellitus Tipo 2 , Nível de Saúde , Paladar , Verduras , Glicemia , Pressão Sanguínea , Composição Corporal , Brassica , Jejum , Glucose , Teste de Tolerância a Glucose , Controle Glicêmico , Humanos , Resistência à Insulina
16.
Contact Dermatitis ; 63(3): 146-50, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20690937

RESUMO

BACKGROUND: The Compositae plant feverfew (Tanacetum parthenium) has long been recognized as an important sensitizer in European Compositae-allergic patients, mainly because of its content of the sesquiterpene lactone parthenolide. Recently, a parthenolide-depleted feverfew extract with claimed anti-inflammatory properties has been developed for use in cosmetics. OBJECTIVE: The aim of the study was to test, on the basis of patch test reactions, whether persons with contact allergy to feverfew could tolerate creams containing this feverfew extract. PATIENTS/MATERIALS/METHODS: Seven patients with feverfew contact allergy were patch tested with two creams containing the feverfew extract. Subsequently, the creams were analysed by liquid chromatography with tandem mass spectrometry to detect parthenolide. RESULTS: Four of the patients tested positive to one of the creams; reactivity was associated with simultaneous positive reactions to parthenolide. This cream was analysed about 2 years later, and no parthenolide was detected, probably because of degradation of the compound. CONCLUSIONS: Topical products containing parthenolide-depleted feverfew extracts may elicit positive patch test reactions in feverfew-sensitive patients. The reactivity may be enhanced by simultaneous testing with parthenolide, but the reactivity is lost over time, probably because of degradation of parthenolide.


Assuntos
Dermatite Alérgica de Contato/imunologia , Testes do Emplastro , Extratos Vegetais/efeitos adversos , Tanacetum parthenium/efeitos adversos , Adulto , Idoso , Dermatite Alérgica de Contato/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pomadas , Sesquiterpenos/química
17.
Food Chem ; 240: 655-661, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28946325

RESUMO

Phycocyanins from cyanobacteria are possible sources for new natural blue colourants. Their chromophore, phycocyanobilin (PCB), was cleaved from the apoprotein by solvolysis in alcohols and alcoholic aqueous solutions. In all cases two PCB isomers were obtained, while different solvent adducts were formed upon the use of different reagents. The reaction is believed to take place via two competing pathways, a concerted E2 elimination and a SN2 nucleophilic substitution. Three cleavage methods were compared in terms of yield and purity: conventional reflux, sealed vessel heated in an oil bath, and microwave assisted reaction. The sealed vessel method is a new approach for fast cleavage of PCB from phycocyanin and gave at 120°C the same yield within 30min compared to 16h by the conventional reflux method (P<0.05). In addition the sealed vessel method resulted in improved purity compared to the other methods. Microwave irradiation increased product degradation.


Assuntos
Corantes de Alimentos/isolamento & purificação , Ficobilinas/isolamento & purificação , Ficocianina/química , Cianobactérias , Ficocianina/isolamento & purificação
18.
Food Funct ; 8(3): 964-974, 2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28197615

RESUMO

Falcarinol (FaOH) and falcarindiol (FaDOH) are found in many food plants of the Apiaceae family. Carrots are a major dietary source of these polyacetylenes. Feeding azoxymethane (AOM)-induced rats with carrots and purified FaOH have previously been shown to inhibit neoplastic transformations in the colon. FaOH and FaDOH have also shown to have a synergistic effect in vitro, resulting in a significant increased cytotoxic activity. Based on these findings the antineoplastic effect of FaOH and FaDOH (purity > 99%) was investigated in the AOM-induced rat model. Twenty rats received rat diet containing 7 µg FaOH per g feed and 7 µg FaDOH per g feed and 20 rats were controls receiving only rat diet. Then carcinogenesis was induced in all 40 rats with the carcinogen AOM. All animals received the designated diet for 2 weeks before AOM induction and continued on the designated diet throughout the experiment. Rats were euthanized 18 weeks after the first AOM injection and macroscopic polyp/cancers were measured, harvested and stained for histology. The difference in sizes of aberrant crypt foci (ACF) were analysed in a Wilcoxon rank sum test, in which the median number of small ACF was 218 in controls and 145 in polyacetylene treated rats (P < 0.001). Fifteen control rats and 8 treated rats had macroscopic tumors (P = 0.027). The number of tumors larger than 3 mm were 6 and 1 in control and treated rats, respectively (P = 0.032). In conclusion dietary supplements with FaOH and FaDOH reduced the number of neoplastic lesions as well as the growth rate of the polyps suggesting a preventive effect of FaOH and FaDOH on the development of colorectal cancer.


Assuntos
Anticarcinógenos/administração & dosagem , Azoximetano/toxicidade , Neoplasias do Colo/prevenção & controle , Daucus carota/química , Di-Inos/administração & dosagem , Álcoois Graxos/administração & dosagem , Extratos Vegetais/administração & dosagem , Poli-Inos/administração & dosagem , Ração Animal/análise , Animais , Anticarcinógenos/metabolismo , Colo/efeitos dos fármacos , Colo/patologia , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Daucus carota/metabolismo , Di-Inos/metabolismo , Álcoois Graxos/metabolismo , Humanos , Masculino , Poli-Inos/metabolismo , Ratos , Ratos Endogâmicos F344
19.
Am J Clin Nutr ; 106(3): 909-920, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28768651

RESUMO

Background: Female age-related estrogen deficiency increases the risk of osteoporosis, which can be effectively treated with the use of hormone replacement therapy. However, hormone replacement therapy is demonstrated to increase cancer risk. Bioavailable isoflavones with selective estrogen receptor affinity show potential to prevent and treat osteoporosis while minimizing or eliminating carcinogenic side effects.Objective: In this study, we sought to determine the beneficial effects of a bioavailable isoflavone and probiotic treatment against postmenopausal osteopenia.Design: We used a novel red clover extract (RCE) rich in isoflavone aglycones and probiotics to concomitantly promote uptake and a favorable intestinal bacterial profile to enhance isoflavone bioavailability. This was a 12-mo, double-blind, parallel design, placebo-controlled, randomized controlled trial of 78 postmenopausal osteopenic women supplemented with calcium (1200 mg/d), magnesium (550 mg/d), and calcitriol (25 µg/d) given either RCE (60 mg isoflavone aglycones/d and probiotics) or a masked placebo [control (CON)].Results: RCE significantly attenuated bone mineral density (BMD) loss at the L2-L4 lumbar spine vertebra (P < 0.05), femoral neck (P < 0.01), and trochanter (P < 0.01) compared with CON (-0.99% and -2.2%; -1.04% and -3.05%; and -0.67% and -2.79, respectively). Plasma concentrations of collagen type 1 cross-linked C-telopeptide was significantly decreased in the RCE group (P < 0.05) compared with CON (-9.40% and -6.76%, respectively). RCE significantly elevated the plasma isoflavone concentration (P < 0.05), the urinary 2-hydroxyestrone (2-OH) to 16α-hydroxyestrone (16α-OH) ratio (P < 0.05), and equol-producer status (P < 0.05) compared with CON. RCE had no significant effect on other bone turnover biomarkers. Self-reported diet and physical activity were consistent and differences were nonsignificant between groups throughout the study. RCE was well tolerated with no adverse events.Conclusions: Twice daily RCE intake over 1 y potently attenuated BMD loss caused by estrogen deficiency, improved bone turnover, promoted a favorable estrogen metabolite profile (2-OH:16α-OH), and stimulated equol production in postmenopausal women with osteopenia. RCE intake combined with supplementation (calcium, magnesium, and calcitriol) was more effective than supplementation alone. This trial was registered at clinicaltrials.gov as NCT02174666.


Assuntos
Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas/tratamento farmacológico , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Estrogênios/metabolismo , Isoflavonas/uso terapêutico , Probióticos/uso terapêutico , Disponibilidade Biológica , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Doenças Ósseas Metabólicas/metabolismo , Osso e Ossos/metabolismo , Colágeno Tipo I/sangue , Método Duplo-Cego , Combinação de Medicamentos , Estrogênios/deficiência , Feminino , Microbioma Gastrointestinal , Humanos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Isoflavonas/sangue , Isoflavonas/farmacocinética , Isoflavonas/farmacologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/prevenção & controle , Peptídeos/sangue , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Trifolium/química
20.
Mol Nutr Food Res ; 61(5)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28012235

RESUMO

SCOPE: Omega-6 (n-6) PUFA-rich diets are generally considered obesogenic in rodents. Here, we examined how long-term intake of a high-fat/high-sucrose (HF/HS) diet based on safflower oil affected metabolism, inflammation, and gut microbiota composition. METHODS AND RESULTS: We fed male C57BL/6J mice a HF/HS diet based on safflower oil-rich in n-6 PUFAs-or a low-fat/low-sucrose diet for 40 wk. Compared to the low-fat/low-sucrose diet, intake of the safflower-based HF/HS diet only led to moderate weight gain, while glucose intolerance developed at week 5 prior to signs of inflammation, but concurrent with increased levels of linoleic acid and arachidonic acid in hepatic phospholipids. Intake of the HF/HS diet resulted in early changes in the gut microbiota, including an increased abundance of Blautia, while late changes coincided with altered inflammatory profiles and increased fasting plasma insulin. Analysis of immune cells in visceral fat and liver revealed no differences between diets before week 40, where the number of immune cells decreased in the liver of HF/HS-fed mice. CONCLUSION: We suggest that a diet-dependent increase in the n-6 to omega-3 (n-3) PUFA ratio in hepatic phospholipids together with gut microbiota changes contributed to early development of glucose intolerance without signs of inflammation.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Sacarose Alimentar/efeitos adversos , Microbioma Gastrointestinal , Intolerância à Glucose/sangue , Óleo de Cártamo/administração & dosagem , Animais , Gorduras na Dieta/administração & dosagem , Sacarose Alimentar/administração & dosagem , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/administração & dosagem , Ácidos Graxos Ômega-6/sangue , Trato Gastrointestinal/microbiologia , Intolerância à Glucose/etiologia , Inflamação/sangue , Inflamação/etiologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
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