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1.
Vet Sci ; 10(9)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37756109

RESUMO

This study aimed to determine the impact of dietary black peppercorn (BP) and xylanase (XYL) alone or in combination on growth performance, dietary energy, nutrient digestibility and blood lipid profile when fed to male Ross 308 broiler chickens from the ages of 7 to 21 d. A wheat-soy-based basal feed that was formulated to be 0.42 MJ lower in metabolizable energy (ME) was mixed. The basal feed was then split into four batches, with the first batch set aside as the basal control; the second batch was supplemented with freshly milled BP; the third batch was supplemented with XYL; the fourth batch was supplemented with both BP and XYL, as in the previous two batches. Each diet was fed to eight pens, with two birds in a pen, following randomization. Feeding BP reduced bird growth and most of the digestibility coefficients but increased blood high-density lipoprotein (p < 0.05). Dietary XYL increased bird growth, dietary ME and nutrient digestibility (p < 0.05). In addition, XYL increased hepatic carotenoids and coenzyme Q10, but reduced blood low-density lipoprotein (p < 0.05). There were no BP by XYL interactions (p > 0.05) observed. Further research is needed to identify the optimum level of BP in broiler diets.

2.
Foods ; 11(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35626986

RESUMO

Stevia rebaudiana Bertoni is a shrub with leaves that have a high concentration of carotenoids such as lutein and zeaxanthin. Egg yolks are a bioavailable source of lutein and zeaxanthin. The consumption of these carotenoids has been linked with improved human health. To investigate the impact of dried stevia leaves at 0%, 1% and 2% on the quality variables, the chemical composition and antioxidant content of eggs, the experiment involved 90 Hy-Line Brown laying hens, housed in 30 enriched layer cages, in groups of three from 22 to 26 weeks of age. The impact on the internal qualities of stored eggs was also examined. Yolks from hens fed stevia had an enriched color compared with the controls. At the end of the experiment, the whole egg, without shell, of birds fed 2% stevia had a higher total carotenoid content (p < 0.001) compared with birds fed 1% and 0% stevia, i.e., 5.16 (µg/g), 4.23 (µg/g) and 2.96 (µg/g), respectively. Storage reduced albumen height and increased albumen pH (p < 0.001). Stevia supplementation did not interact (p > 0.05) with storage time among the egg quality variables. Consuming eggs from hens fed stevia may increase carotenoids in human diet.

3.
Res Vet Sci ; 141: 63-65, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34688041

RESUMO

Dihydroquercetin (DHQ), also known as taxifolin, is a natural antioxidant that can be commercially obtained by extraction from Siberian Larch (Larix sibirica). Four wheat-soy based diets, formulated to contain 0, 0.5, 1.5 and 4.5 g/kg of supplementary DHQ were prepared. Each diet was fed ad libitum to birds in seven pens (three birds in each pen) in a randomised block design from 7 to 21 days of age. The effect of DHQ on weight gain was not significant overall (P > 0.05), although there was an indication of a linear increase (L < 0.05). The blood glutathione peroxidase responded (P < 0.001) in a curvilinear manner (L < 0.001 and Q < 0.05) to increased dietary DHQ. The results from this study indicate that dietary DHQ supplementation may be beneficial at levels greater than 1.5 g/kg feed, due to improved bird antioxidant status. Further research to define an upper inclusion level and optimal timing for phase feeding programmes is warranted.


Assuntos
Antioxidantes , Galinhas , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Quercetina/análogos & derivados
4.
Arch Anim Nutr ; 74(6): 496-511, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32967440

RESUMO

The use of natural antioxidants, in particular polyphenols such as dihydroquercetin (DHQ), in animal nutrition has recently increased in popularity. This may partly be due to the risk of increased incidences of heat stress associated with raising livestock in warmer ambient temperatures, facilitated by global warming, reducing antioxidant capacity. The current research demonstrates the effect of dietary DHQ, vitaminEand standard or high ambient temperatures on growth performance, energy and nutrient metabolism, gastrointestinal tract (GIT) development, jejunal villus morphometry and antioxidant status in broiler chickens. Each of the four experimental diets was fed to 16 pens of five birds, which were allocated to four rooms (four pens in each room). The temperature in two rooms was maintained at aconstant 35°C (high temperature; HT), and the temperature in the other two rooms was gradually reduced from 27°C at 7 dof age to 22°C at 20 dof age (standard temperature; ST). Rearing birds at HT reduced feed intake, weight gain, weight of small intestine, total GIT, liver, spleen, heart, villus height, villus surface area and lowered blood glutationperoxidase (GSH-Px). Dietary DHQ increased blood GSH-Px and total antioxidant status, increased heart weight and reduced caecal size. When fed separately, DHQ and vitamin E improved hepatic vitamin E concentration. Feeding vitamin Eincreased spleen and liver weights. When fed together, DHQ and vitamin Ereduced villus height, villus height to crypt depth ratio and villus surface area. Temperature and antioxidants did not affect energy and nutrient metabolism. There were no effects of dietary antioxidants on growth performance of broiler chickens and there were no mortalities. At present, it is unclear if feeding antioxidants (in particular DHQ) at different levels, using different dietary formulations, and rearing birds under arange of environmental conditions may be effective at enhancing production performance and bird health in hot ambient climates.


Assuntos
Antioxidantes/metabolismo , Galinhas/metabolismo , Trato Gastrointestinal/crescimento & desenvolvimento , Jejuno/anatomia & histologia , Quercetina/análogos & derivados , Vitamina E/metabolismo , Vitaminas/metabolismo , Ração Animal/análise , Animais , Antioxidantes/administração & dosagem , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Trato Gastrointestinal/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Quercetina/administração & dosagem , Quercetina/metabolismo , Distribuição Aleatória , Temperatura , Vitamina E/administração & dosagem , Vitaminas/administração & dosagem
5.
Biotechnol Adv ; 38: 107322, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30476540

RESUMO

Worldwide, colorectal cancer (CRC) remains a major cancer type and leading cause of death. Unfortunately, current medical treatments are not sufficient due to lack of effective therapy, adverse side effects, chemoresistance and disease recurrence. In recent decades, epidemiologic observations have highlighted the association between the ingestion of several phytochemical-enriched foods and nutrients and the lower risk of CRC. According to preclinical studies, dietary phytochemicals exert chemopreventive effects on CRC by regulating different markers and signaling pathways; additionally, the gut microbiota plays a role as vital effector in CRC onset and progression, therefore, any dietary alterations in it may affect CRC occurrence. A high number of studies have displayed a key role of growth factors and their signaling pathways in the pathogenesis of CRC. Indeed, the efficiency of dietary phytochemicals to modulate carcinogenic processes through the alteration of different molecular targets, such as Wnt/ß-catenin, PI3K/Akt/mTOR, MAPK (p38, JNK and Erk1/2), EGFR/Kras/Braf, TGF-ß/Smad2/3, STAT1-STAT3, NF-кB, Nrf2 and cyclin-CDK complexes, has been proven, whereby many of these targets also represent the backbone of modern drug discovery programs. Furthermore, epigenetic analysis showed modified or reversed aberrant epigenetic changes exerted by dietary phytochemicals that led to possible CRC prevention or treatment. Therefore, our aim is to discuss the effects of some common dietary phytochemicals that might be useful in CRC as preventive or therapeutic agents. This review will provide new guidance for research, in order to identify the most studied phytochemicals, their occurrence in foods and to evaluate the therapeutic potential of dietary phytochemicals for the prevention or treatment of CRC by targeting several genes and signaling pathways, as well as epigenetic modifications. In addition, the results obtained by recent investigations aimed at improving the production of these phytochemicals in genetically modified plants have been reported. Overall, clinical data on phytochemicals against CRC are still not sufficient and therefore the preventive impacts of dietary phytochemicals on CRC development deserve further research so as to provide additional insights for human prospective studies.


Assuntos
Neoplasias Colorretais , Anticarcinógenos , Humanos , Fosfatidilinositol 3-Quinases , Compostos Fitoquímicos , Estudos Prospectivos
6.
Biotechnol Adv ; 36(2): 358-370, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29277308

RESUMO

Organisms are constantly exposed to a broad range of pathological and stress-inducing agents, allergens and environmental chemicals that can induce infections, toxicity or other undesirable reactions. Our immune system has evolved over time in order to efficiently respond to these exogenous insults and maintain homeostasis. In particular, the innate immune system acts as primary barrier to prevent the entrance of invasive agents or allergens. This system is comprised of a diversity of cell types that are rapidly activated by recognition of common structures present in many potential pathogens known as pathogen-associated molecular patterns (PAMPs). The nuclear factor erythroid 2 related factor 2 (Nrf2) is a relevant basic leucine zipper (bZIP) transcription factor that is essential in the regulation of cell cycle homeostasis, cytoprotection, and innate immunity when cells are under stressful conditions. Although the role of Nrf2 in activating the expression of protective genes - such as antioxidant or anti-inflammatory - is known, its role in innate immunity and immune-related gene expression remains not yet clear. The present review summarizes current knowledge on Nrf2 signaling pathway structure and activity under both physiological state and upon oxidative stress. In addition, the relation between Nrf2 signaling pathway and the innate immune system is discussed, highlighting the potential therapeutic effects of diverse natural and synthetic compounds as Nrf2 regulators.


Assuntos
Imunidade Inata/fisiologia , Fator 2 Relacionado a NF-E2 , Animais , Humanos , Inflamação , Camundongos , Estresse Oxidativo , Ratos , Transdução de Sinais
7.
Biotechnol Adv ; 36(6): 1779-1799, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29129653

RESUMO

The current trend of combining state of the art technologies with quondam treatments in order to overcome existing gaps in the clinical area determined an increased interest into polyphenols, common dietary phytochemicals, for the prevention and treatment of chronic diseases, especially cancer. The reemergence of polyphenols in the cancer field is sustained by advanced-omics technologies able to identify coding and non-coding genes and their related signaling pathways modulated by natural compounds. Identification of the structural correspondence between interacting molecules will allow the development of more targeted and informed therapeutic strategies for cancer management.


Assuntos
Antineoplásicos , Neoplasias , Compostos Fitoquímicos , Extratos Vegetais , RNA não Traduzido , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , RNA não Traduzido/efeitos dos fármacos , RNA não Traduzido/metabolismo
8.
Food Chem Toxicol ; 111: 114-124, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29129665

RESUMO

Mechanisms how colorectal cancer (CRC) cells penetrate blood micro-vessel endothelia and metastasise is poorly understood. To study blood endothelial cell (BEC) barrier breaching by CRC emboli, an in vitro assay measuring BEC-free areas underneath SW620 cell spheroids, so called "circular chemorepellent induced defects" (CCIDs, appearing in consequence of endothelial retraction), was adapted and supported by Western blotting, EIA-, EROD- and luciferase reporter assays. Inhibition of ALOX12 or NF-κB in SW620 cells or BECs, respectively, caused attenuation of CCIDs. The FDA approved drugs vinpocetine [inhibiting ALOX12-dependent 12(S)-HETE synthesis], ketotifen [inhibiting NF-κB], carbamazepine and fenofibrate [inhibiting 12(S)-HETE and NF-κB] significantly attenuated CCID formation at low µM concentrations. In the 5-FU-resistant SW620-R/BEC model guanfacine, nifedipine and proadifen inhibited CCIDs stronger than in the naïve SW620/BEC model. This indicated that in SW620-R cells formerly silent (yet unidentified) genes became expressed and targetable by these drugs in course of resistance acquisition. Fenofibrate, and the flavonoids hispidulin and apigenin, which are present in medicinal plants, spices, herbs and fruits, attenuated CCID formation in both, naïve- and resistant models. As FDA-approved drugs and food-flavonoids inhibited established and acquired intravasative pathways and attenuated BEC barrier-breaching in vitro, this warrants testing of these compounds in CRC models in vivo.


Assuntos
Neoplasias Colorretais/patologia , Células Endoteliais/fisiologia , Endotélio Vascular/fisiologia , Flavonoides/farmacologia , Esferoides Celulares/fisiologia , Araquidonato 12-Lipoxigenase/genética , Araquidonato 12-Lipoxigenase/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Metástase Neoplásica/fisiopatologia , Preparações Farmacêuticas
9.
Neurosci Biobehav Rev ; 73: 39-47, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27914941

RESUMO

Searching for effective therapeutic agents to prevent neurodegeneration is a challenging task due to the growing list of neurodegenerative disorders associated with a multitude of inter-related pathways. The induction and inhibition of several different signaling pathways has been shown to slow down and/or attenuate neurodegeneration and decline in cognition and locomotor function. Among these signaling pathways, a new class of enzymes known as sirtuins or silent information regulators of gene transcription has been shown to play important regulatory roles in the ageing process. SIRT1, a nuclear sirtuin, has received particular interest due to its role as a deacetylase for several metabolic and signaling proteins involved in stress response, apoptosis, mitochondrial function, self-renewal, and neuroprotection. A new strategy to treat neurodegenerative diseases is targeted therapy. In this paper, we reviewed up-to-date findings regarding the targeting of SIRT1 by polyphenolic compounds, as a new approach in the search for novel, safe and effective treatments for neurodegenerative diseases. .


Assuntos
Doenças Neurodegenerativas , Humanos , Mitocôndrias , Polifenóis , Transdução de Sinais , Sirtuínas
10.
Cancer Lett ; 380(1): 174-83, 2016 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-27390016

RESUMO

Secretion of 12(S)-HETE by breast cancer emboli provokes "circular chemorepellent induced defects" (CCIDs) in the adjacent lymphatic vasculature facilitating their intravasation and lymph node metastasis which determines prognosis. Therefore, elucidating the mechanism of lymph endothelial cell (LEC) wall disintegration may provide cues for anti-metastatic intervention. The role of intracellular free Ca(2+) for CCID formation was investigated in LECs using MCF-7 or MDA-MB231 breast cancer cell spheroids in a three-dimensional cell co-culture model. 12(S)-HETE elevated the Ca(2+) level in LEC by activating PLC/IP3. Downstream, the Ca(2+)-calmodulin kinase MYLK contributed to the phosphorylation of Ser19-MLC2, LEC contraction and CCID formation. Approved clinical drugs, lidoflazine, ketotifen, epiandrosterone and cyclosporine, which reportedly disturb cellular calcium supply, inhibited 12(S)-HETE-induced Ca(2+) increase, Ser19-MLC2 phosphorylation and CCID formation. This treatment strategy may reduce spreading of breast cancer through lymphatics.


Assuntos
Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/farmacologia , Neoplasias da Mama/patologia , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Movimento Celular , Células Endoteliais/efeitos dos fármacos , Vasos Linfáticos/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Quelantes de Cálcio/farmacologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Miosinas Cardíacas/metabolismo , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Feminino , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Metástase Linfática , Vasos Linfáticos/metabolismo , Células MCF-7 , Cadeias Leves de Miosina/metabolismo , Quinase de Cadeia Leve de Miosina/genética , Quinase de Cadeia Leve de Miosina/metabolismo , Permeabilidade , Fosforilação , Interferência de RNA , Serina , Esferoides Celulares , Fatores de Tempo , Transfecção , Fosfolipases Tipo C/metabolismo
11.
Hum Mol Genet ; 25(22): 5006-5016, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28171546

RESUMO

A causal link between overexpression of aryl hydrocarbon receptor (AHR) and its target cytochrome P450 1A1 (CYP1A1) and metastatic outgrowth of various cancer entities has been established. Nevertheless, the mechanism how AHR/CYP1A1 support metastasis formation is still little understood. In vitro we discovered a potential mechanism facilitating tumour dissemination based on the production of 12(S)-hydroxyeicosatetraenoic acid (12(S)-HETE). Utilising a three-dimensional lymph endothelial cell (LEC) monolayer & MDA-MB231 breast cancer cell spheroid co-culture model in combination with knock-down approach allowed elucidation of the molecular/biochemical basis of AHR/CYP1A1-induced tumour breaching through the LEC barrier. Enzyme immunoassay evidenced the potential of recombinant CYP1A1 to synthesise 12(S)-HETE in vitro and qPCR and Western blotting measured gene and protein expression in specific experimental settings. In detail, AHR induced CYP1A1 expression and 12(S)-HETE secretion in tumour spheroids, which caused LEC junction retraction thereby forming large discontinuities allowing transmigration of the tumour. This was enforced by the activating AHR ligand 6-formylindolo (3,3-b)carbazole (FICZ), or inhibited by the AHR antagonist 3,3'-diindolylmethane (DIM) as well as by siRNA against AHR and CYP1A1. AHR and NF-κB were negatively cross talking and therefore, the inhibition of AHR (but not CYP1A1) induced RELA, RELB, NFKB1, NFKB2 and the NF-κB target MMP1, which itself promotes tumour intravasation by a mechanism that is different from 12(S)-HETE. Conversely, the inhibition of NFKB2 induced AHR, CYP1A1 and 12(S)-HETE synthesis. The approved clinical drugs guanfacine and vinpocetine, which inhibit CYP1A1 and NF-κB, respectively, significantly inhibited LEC barrier breaching in vitro indicating an option to reduce metastatic dissemination.


Assuntos
Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/biossíntese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Neoplasias da Mama/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Neoplasias da Mama/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Técnicas de Silenciamento de Genes , Humanos , Metástase Linfática , Linfócitos/metabolismo , Células MCF-7 , Metaloproteinase 1 da Matriz/metabolismo , NF-kappa B/metabolismo , Metástase Neoplásica , Transdução de Sinais , Esferoides Celulares , Células Tumorais Cultivadas
12.
Phytomedicine ; 22(9): 862-74, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26220634

RESUMO

BACKGROUND: The t(2;5)(p23;q35) chromosomal translocation results in the expression of the fusion protein NPM/ALK that when expressed in T-lymphocytes gives rise to anaplastic large cell lymphomas (ALCL). In search of new therapy options the dichloromethane extract of the ethnomedicinal plant Neurolaena lobata (L.) R.Br. ex Cass was shown to inhibit NPM/ALK expression. PURPOSE: Therefore, we analysed whether the active principles that were recently isolated and found to inhibit inflammatory responses specifically inhibit growth of NPM/ALK+ ALCL, leukaemia and breast cancer cells, but not of normal cells, and the intravasation through the lymphendothelial barrier. METHODS: ALCL, leukaemia and breast cancer cells, and normal peripheral blood mononuclear cells (PBMCs) were treated with isolated sesquiterpene lactones and analysed for cell cycle progression, proliferation, mitochondrial activity, apoptosis, protein and mRNA expression, NF-κB and cytochrome P450 activity, 12(S)-HETE production and lymphendothelial intravasation. RESULTS: In vitro treatment of ALCL by neurolenin B suppressed NPM/ALK, JunB and PDGF-Rß expression, inhibited the growth of ALCL cells late in M phase, and induced apoptosis via caspase 3 without compromising mitochondrial activity (as a measure of general exogenic toxicity). Moreover, neurolenin B attenuated tumour spheroid intravasation probably through inhibition of NF-κB and CYP1A1. CONCLUSION: Neurolenin B specifically decreased pro-carcinogenic NPM/ALK expression in ALK+ ALCL cells and, via the inhibition of NF-kB signalling, attenuated tumour intra/extravasation into the lymphatics. Hence, neurolenin B may open new options to treat ALCL and to manage early metastatic processes to which no other therapies exist.


Assuntos
Asteraceae/química , Lactonas/farmacologia , Linfoma Anaplásico de Células Grandes/patologia , NF-kappa B/metabolismo , Proteínas Tirosina Quinases/metabolismo , Sesquiterpenos de Germacrano/farmacologia , Sesquiterpenos/farmacologia , Apoptose , Ciclo Celular , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Estrutura Molecular , Plantas Medicinais/química , Transdução de Sinais
13.
Mutat Res ; 777: 79-90, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25989051

RESUMO

Pluchea odorata is ethno pharmaceutically used to treat inflammation-associated disorders. The dichloromethane extract (DME) was tested in the carrageenan-induced rat paw oedema assay investigating its effect on inflammation that was inhibited by 37%. Also an in vitro anti-neoplastic potential was reported. However, rather limited information about the bio-activity of purified compounds and their cellular mechanisms are available. Therefore, two of the most abundant eudesmanes in P. odorata were isolated and their anti-neoplastic and anti-intravasative activities were studied. HL-60 cells were treated with P. odorata compounds and metabolic activity, cell number reduction, cell cycle progression and apoptosis induction were correlated with relevant protein expression. Tumour cell intravasation through lymph endothelial monolayers was measured and potential causal mechanisms were analyzed by Western blotting. Compound PO-1 decreased the metabolic activity of HL-60 cells (IC50 = 8.9 µM after 72 h) and 10 µM PO-1 induced apoptosis, while PO-2 showed just weak anti-neoplastic activities at concentrations beyond 100 µM. PO-1 arrested the cell cycle in G1 and this correlated with induction of JunB expression. Independent of this mechanism 25 µM PO-1 decreased MCF-7 spheroid intravasation through the lymph endothelial barrier. Hence, PO-1 inhibits an early step of metastasis, impairs unrestricted proliferation and induces apoptosis at low micromolar concentrations. These results warrant further testing in vivo to challenge the potential of PO-1 as novel lead compound.


Assuntos
Apoptose/efeitos dos fármacos , Asteraceae/química , Proliferação de Células/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sesquiterpenos de Eudesmano/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Células HL-60 , Humanos , Concentração Inibidora 50 , Masculino , Ratos , Ratos Sprague-Dawley , Saponinas/farmacologia , Espirostanos/farmacologia
14.
Cancer Lett ; 356(2 Pt B): 994-1006, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25444930

RESUMO

An apolar extract of the traditional medicinal plant Neurolaena lobata inhibited the expression of the NPM/ALK chimera, which is causal for the majority of anaplastic large cell lymphomas (ALCLs). Therefore, an active principle of the extract, the furanoheliangolide sesquiterpene lactone lobatin B, was isolated and tested regarding the inhibition of ALCL expansion and tumour cell intravasation through the lymphendothelium. ALCL cell lines, HL-60 cells and PBMCs were treated with plant compounds and the ALK inhibitor TAE-684 to measure mitochondrial activity, proliferation and cell cycle progression and to correlate the results with protein- and mRNA-expression of selected gene products. Several endpoints indicative for cell death were analysed after lobatin B treatment. Tumour cell intravasation through lymphendothelial monolayers was measured and potential causal mechanisms were investigated analysing NF-κB- and cytochrome P450 activity, and 12(S)-HETE production. Lobatin B inhibited the expression of NPM/ALK, JunB and PDGF-Rß, and attenuated proliferation of ALCL cells by arresting them in late M phase. Mitochondrial activity remained largely unaffected upon lobatin B treatment. Nevertheless, caspase 3 became activated in ALCL cells. Also HL-60 cell proliferation was attenuated whereas PBMCs of healthy donors were not affected by lobatin B. Additionally, tumour cell intravasation, which partly depends on NF-κB, was significantly suppressed by lobatin B most likely due to its NF-κB-inhibitory property. Lobatin B, which was isolated from a plant used in ethnomedicine, targets malignant cells by at least two properties: I) inhibition of NPM/ALK, thereby providing high specificity in combating this most prevalent fusion protein occurring in ALCL; II) inhibition of NF-κB, thereby not affecting normal cells with low constitutive NF-κB activity. This property also inhibits tumour cell intravasation into the lymphatic system and may provide an option to manage this early step of metastatic progression.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Asteraceae/química , Endotélio Linfático/efeitos dos fármacos , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Linfoma Anaplásico de Células Grandes/patologia , NF-kappa B/antagonistas & inibidores , Extratos Vegetais/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Sesquiterpenos/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Caspases/genética , Caspases/metabolismo , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Endotélio Linfático/patologia , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Linfoma Anaplásico de Células Grandes/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , NF-kappa B/genética , NF-kappa B/metabolismo , Invasividade Neoplásica , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
15.
Planta Med ; 78(3): 219-24, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22124950

RESUMO

The therapy of type-2 diabetes mellitus is one of the major challenges of our age. A possible strategy to prevent the progression of this disease is the inhibition of protein tyrosine phosphatase 1B (PTP1B), a major negative regulator in the insulin and leptin signalling pathway. Phellodendri amurensis cortex is a well-known Asian herbal drug traditionally used as antiphlogistic, antibacterial, and anti-inflammatory agent, and its efficacy against diabetes-related symptoms is reported as well. However, information regarding active principle(s) or the molecular mode of action was scarce. By bioguided isolation using an IN VITRO enzyme assay with human recombinant PTP1B, (9 Z)-octadec-9-enoic acid (oleic acid) could be identified as a major PTP1B inhibitor in the bark of Phellodendron amurENSE Rupr. (Rutaceae); it showed an IC50 value of 6.2 µM. Consistent with this inhibition of PTP1B, oleic acid was capable of enhancing insulin signalling in wild-type, but not PTP1B knockout fibroblasts. By testing a series of other fatty acids of different chain length and degree of saturation, their general PTP1B-inhibitory potential in the micromolar range was observed. More pronounced effects were associated with a longer carbon backbone and saturation of the double bonds. Therefore, our work provides first scientific evidences for the antidiabetic properties of P. amurense via a new target, effects which seem to be explainable by oleic acid. The discovery of a PTP1B inhibition by many fatty acids also adds a novel facet to the pharmacological properties of a class of compounds that is found in many food items in considerable amount and triggers speculation over their possible involvement in the feedback regulation of cellular fatty acid synthesis.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Ácidos Oleicos/farmacologia , Phellodendron/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Animais , Diabetes Mellitus Tipo 2/enzimologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Humanos , Insulina/metabolismo , Camundongos , Ácidos Oleicos/isolamento & purificação , Fitoterapia , Extratos Vegetais/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Transdução de Sinais/efeitos dos fármacos
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