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1.
NPJ Biofilms Microbiomes ; 7(1): 65, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354062

RESUMO

Shifts in subsistence strategy among Native American people of the Amazon may be the cause of typically western diseases previously linked to modifications of gut microbial communities. Here, we used 16S ribosomal RNA sequencing to characterise the gut microbiome of 114 rural individuals, namely Xikrin, Suruí and Tupaiú, and urban individuals from Belém city, in the Brazilian Amazon. Our findings show the degree of potential urbanisation occurring in the gut microbiome of rural Amazonian communities characterised by the gradual loss and substitution of taxa associated with rural lifestyles, such as Treponema. Comparisons to worldwide populations indicated that Native American groups are similar to South American agricultural societies and urban groups are comparable to African urban and semi-urban populations. The transitioning profile observed among traditional populations is concerning in light of increasingly urban lifestyles. Lastly, we propose the term "tropical urban" to classify the microbiome of urban populations living in tropical zones.


Assuntos
Bactérias/classificação , Microbioma Gastrointestinal/fisiologia , Metagenômica , Urbanização , Bactérias/genética , Biodiversidade , Brasil , Microbioma Gastrointestinal/genética , Humanos , Estilo de Vida , RNA Ribossômico 16S/genética , População Rural , População Urbana
2.
Food Chem Toxicol ; 64: 200-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24296135

RESUMO

The aim of this study was to investigate the effect of Naringin on pre-neoplastic colorectal lesions induced by chemical carcinogen in rats. Female Wistar rats weighing 130.8±27.1 g received weekly one subcutaneous injection of 1,2-dimethylhydrazine (DMH, 20 mg/kg) for 10 weeks. The animals were divided into 5 groups with 6 animals in each group. Group 1: 0.9% saline; Group 2: DMH+0.9% saline; Group 3: DMH+Naringin (10 mg/kg); Group 4: DMH+Naringin (100 mg/kg); Group 5: DMH+Naringin (200 mg/kg). G2 and G3 showed a significant increase in ACF number, AgNOR/nucleus and mitosis compared to G1. G4 and G5 presented a significant reduction in these parameters compared to G2. The number of cells producing acidic and neutral mucins, red blood cells and the level of antioxidant minerals, such as copper, magnesium, selenium and zinc, were significantly reduced in G2 and G3, but similar in G4 and G5 compared to G1. Naringin, especially at 200 mg/kg, was effective in reducing the number of pre-neoplastic lesions in rats exposed to DMH. Some of these effects may be due to reduction in cellular proliferation and tissue levels of iron together with the recovery of antioxidant mineral levels induced by this flavonoid.


Assuntos
Neoplasias Colorretais/prevenção & controle , Flavanonas/farmacologia , Lesões Pré-Cancerosas/prevenção & controle , 1,2-Dimetilidrazina/toxicidade , Animais , Carcinógenos/toxicidade , Neoplasias Colorretais/induzido quimicamente , Feminino , Camundongos , Microscopia Eletrônica de Varredura , Lesões Pré-Cancerosas/induzido quimicamente , Ratos , Ratos Wistar
3.
Cell Tissue Res ; 352(2): 327-39, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23468207

RESUMO

Phenolic compounds are naturally occurring, bioactive substances with marked antioxidant and anti-inflammatory potential. The flavonoid chrysin, found in high levels in honey bee propolis, inhibits the activity of enzymes involved in carcinogenesis. We have investigated the effect of chrysin on pre-neoplastic colorectal lesions (ACF, aberrant crypt foci) in a rat model of chemical carcinogenesis induced by 1,2-dimethylhydrazine (DMH). Female Wistar rats weighing 137.2 ± 24.3 g received weekly one subcutaneous injection of DMH (20 mg/kg) for 10 weeks. The animals were divided into five groups each with seven animals: Group 1, 0.9% saline; Group 2, DMH+0.9% saline; Group 3, DMH+chrysin (10 mg/kg); Group 4, DMH+chrysin (100 mg/kg); Group 5, DMH+chrysin (200 mg/kg). Groups 2 and 3 showed a significant increase in ACF number, nucleolus organizer regions per enterocyte nucleus and nitrite/nitrate serum levels compared with Group 1. Groups 4 and 5 presented a significant reduction in all these parameters compared with Group 2. The levels of antioxidant minerals (copper, magnesium, selenium, zinc) and the number of enteroendocrine and mucin-producing cells were significantly reduced in Groups 2 and 3 but were similar in Groups 4 and 5 compared with Group 1. Chrysin, at 100 mg/kg and 200 mg/kg, was effective in attenuating pathological colorectal remodeling, reducing the number of pre-neoplastic lesions in rats exposed to DMH. Some of these effects might be attributable to the recovery of antioxidant mineral levels, a reduction in systemic nitrosative stress and an inhibition of the cellular proliferation induced by this flavonoid.


Assuntos
Colo/efeitos dos fármacos , Neoplasias Colorretais/prevenção & controle , Flavonoides/farmacologia , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/tratamento farmacológico , Reto/efeitos dos fármacos , 1,2-Dimetilidrazina , Animais , Carcinógenos , Colo/enzimologia , Colo/patologia , Neoplasias Colorretais/induzido quimicamente , Feminino , Lesões Pré-Cancerosas/patologia , Ratos , Ratos Wistar , Reto/enzimologia , Reto/patologia
4.
Phytomedicine ; 15(4): 237-44, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17689943

RESUMO

Latex from Caricaceae contains proteolytic enzymes localized in the fruit, which are used ethnopharmacologically to treat digestive disorders. Some of these proteins display proliferative properties when probed with mammalian cells, suggesting a role in the reconstruction of wounded tissue. We tested the efficacy of a proteolytic fraction derived from Carica candamarcensis, designated as P1G10 in experimental rodent models, to protect and heal chemically induced gastric ulcers. The protective effect of oral administration of P1G10 fraction was analyzed in indomethacin-treated Wistar animals. The healing effect of P1G10 was studied following sub-serous injection of acetic acid in a Wistar rat model. The results show that P1G10 between 0.1 and 10 mg/kg protect indomethacin but not ethanol-induced gastric ulcers. The maximal protection attained was 67% with 10 mg/kg of P1G10. The healing rate by 10 mg/kg of P1G10 using the acetic acid ulcerogenic model is similar to that of omeprazole (10 mg/kg) or ranitidine (100 mg/kg). The effect of P1G10 at 10 mg/kg seems to be mediated by an increase in the mucus content by 25% and stimulation of angiogenesis by 64% in a manner similar to growth factors. These results confirm the protective and healing role of proteinases from C. candamarcensis.


Assuntos
Carica/enzimologia , Cisteína Endopeptidases/uso terapêutico , Látex/química , Fitoterapia , Úlcera Gástrica/tratamento farmacológico , Animais , Antiulcerosos , Carica/química , Cisteína Endopeptidases/isolamento & purificação , Cisteína Endopeptidases/farmacologia , Frutas/química , Frutas/enzimologia , Neovascularização Fisiológica/efeitos dos fármacos , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/prevenção & controle
5.
Planta Med ; 71(3): 244-8, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15770545

RESUMO

In a prior study we showed evidence that latex from Carica candamarcensis contains a protein fraction that stimulates mammalian cell proliferation. In this report we describe the isolation of two proteinases responsible for this effect. Both proteinases (P1, P2) display a relative mass of 23 kDa and following chromatographic purification stimulate proliferation of fibroblastic and epithelial cells. P2 added to L929 fibroblasts at 2.5 nM enhances proliferation by 60 %. We further demonstrate that its cellular effect is linked to an increase in activity of Erk2, a component of the MAP kinase pathway. To our knowledge, this is the first known plant proteinase to exert a proliferative effect in mammalian cells. This novel mitogenic property attributed to a purified cysteine proteinase may explain some of the therapeutic actions attributed to these enzymes.


Assuntos
Carica , Látex/farmacologia , Mitógenos/farmacologia , Peptídeo Hidrolases/farmacologia , Fitoterapia , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular/efeitos dos fármacos , Cricetinae , Relação Dose-Resposta a Droga , Feminino , Frutas , Látex/química , Mitógenos/química , Peptídeo Hidrolases/química
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