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1.
Food Res Int ; 173(Pt 1): 113334, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803644

RESUMO

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) of the gastrointestinal tract. The etiology is not fully understood, but environmental, microbial, and immunologic factors, as well as a genetic predisposition, play a role. UC is characterized by episodes of abdominal pain, diarrhea, bloody stools, weight loss, severe colonic inflammation, and ulceration. Despite the increase in the frequency of UC and the deterioration of the quality of life, there are still patients who do not respond well to available treatment options. Against this background, natural products such as polysaccharides are becoming increasingly important as they protect the intestinal mucosa, promote wound healing, relieve inflammation and pain, and restore intestinal motility. In this study, we investigated the effect of a polysaccharide isolated from the biomass of Campomanesia adamantium and Campomanesia pubescens (here referred to as CPW) in an experimental model of acute and chronic ulcerative colitis induced by dextran sulfate sodium (DSS). CPW reversed weight loss, increased disease activity index (DAI), bloody diarrhea, and colon shortening. In addition, CPW reduced visceral mechanical hypersensitivity, controlled oxidative stress and inflammation, and protected the mucosal barrier. CPW is not absorbed in the intestine, does not inhibit cytochrome P450 proteins, and does not exhibit AMES toxicity. These results suggest that CPW attenuates DSS-induced acute and chronic colitis in mice and may be a potential alternative treatment for UC.


Assuntos
Colite Ulcerativa , Humanos , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Qualidade de Vida , Modelos Animais de Doenças , Inflamação , Redução de Peso , Diarreia
2.
Molecules ; 28(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36615553

RESUMO

Liquidambar styraciflua L. is an aromatic species, popularly used in traditional Chinese medicine to treat diarrhea, dysentery, coughs, and skin sores. The present study was designed to investigate the chemical composition and biological potential of extracts obtained from the fruits of this plant. For the chemical evaluation, it was used mainly liquid and gas chromatography, plus NMR, and colorimetric methods. The aqueous extract (EA) originated two other fractions: an aqueous (P-EA) and an ethanolic (S-EA). The three extracts were composed of proteins, phenolic compounds, and carbohydrates in different proportions. The analyses showed that the polysaccharide extract (P-EA) contained pectic polysaccharides, such as acetylated and methyl esterified homogalacturonans together with arabinogalactan, while the fraction S-EA presented phenolic acids and terpenes such as gallic acid, protocathecuic acid, liquidambaric acid, combretastatin, and atractyloside A. EA, P-EA, and S-EA showed antioxidant activity, with IC50 values of 4.64 µg/mL, 16.45 µg/mL, and 3.67 µg/mL, respectively. The cytotoxicity followed the sequence S-EA > EA > P-EA, demonstrating that the toxic compounds were separated from the non-toxic ones by ethanol precipitation. While the fraction S-EA is very toxic to any cell line, the fraction P-EA is a promising candidate for studies against cancer due to its high toxicity to tumoral cells and low toxicity to normal cells.


Assuntos
Antineoplásicos , Liquidambar , Frutas , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Liquidambar/química , Antioxidantes/farmacologia , Antioxidantes/química , Antineoplásicos/farmacologia
3.
Science ; 377(6603): 276-284, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35857588

RESUMO

γδ T cells represent a substantial fraction of intestinal lymphocytes at homeostasis, but they also constitute a major lymphocyte population infiltrating colorectal cancers (CRCs); however, their temporal contribution to CRC development or progression remains unclear. Using human CRC samples and murine CRC models, we found that most γδ T cells in premalignant or nontumor colons exhibit cytotoxic markers, whereas tumor-infiltrating γδ T cells express a protumorigenic profile. These contrasting T cell profiles were associated with distinct T cell receptor (TCR)-Vγδ gene usage in both humans and mice. Longitudinal intersectional genetics and antibody-dependent strategies targeting murine γδ T cells enriched in the epithelium at steady state led to heightened tumor development, whereas targeting γδ subsets that accumulate during CRC resulted in reduced tumor growth. Our results uncover temporal pro- and antitumor roles for γδ T cell subsets.


Assuntos
Neoplasias Colorretais , Citotoxicidade Imunológica , Intestinos , Linfócitos Intraepiteliais , Receptores de Antígenos de Linfócitos T gama-delta , Animais , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Humanos , Intestinos/imunologia , Linfócitos Intraepiteliais/imunologia , Camundongos , Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores de Antígenos de Linfócitos T gama-delta/fisiologia
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