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1.
Carbohydr Res ; 535: 108986, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38042036

RESUMO

The regulation of metastasis-related cellular aspects of two structurally similar AGIs from prunes tea infusion, with different molar masses, was studied in vitro against Triple Wild-Type metastatic melanoma (TWM) from murine and human origin. The higher molar mass AGI (AGI-78KDa) induced TWMs cells death and, in murine cell line, it decreased some metastasis-related cellular processes: invasiveness capacity, cell-extracellular matrix interaction, and colonies sizes. The lower molar mass AGI (AGI-12KDa) did not induce cell death but decreased TWMs proliferation rate and, in murine cell line, it decreased cell adhesion and colonies sizes. Both AGIs alter the clonogenic capacity of human cell line. In spite to understand why we saw so many differences between AGIs effects on murine and human cell lines we performed in silico analysis that demonstrated differential gene expression profiles between them. Complementary network topological predictions suggested that AGIs can modulate multiple pathways in a specie-dependent manner, which explain differential results obtained in vitro between cell lines. Our results pointed to therapeutic potential of AGIs from prunes tea against TWMs and showed that molecular weight of AGIs may influence their antitumor effects.


Assuntos
Galactanos , Melanoma , Humanos , Camundongos , Animais , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Peso Molecular , Chá , Linhagem Celular Tumoral
2.
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
3.
Nutr Cancer ; 75(5): 1382-1398, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36974004

RESUMO

Gastrointestinal toxicity, including diarrhea and inflammation, is commonly observed with the use of 5-fluorouracil (5-FU). Several studies have shown that polysaccharides are interesting bioactive macromolecules for the treatment or prevention of gastrointestinal diseases. Therefore, in this study, the effect of a polysaccharide fraction from a mixture of two Guavira species (Campomanesia adamantium and Campomanesia pubescens), referred to here as CPW, on the development of intestinal mucositis was investigated. Intestinal mucositis was induced by a single injection of 5-FU (450 mg/kg), and various doses of CPW (3-100 mg/kg) were tested. CPW attenuated disease development and prevented small bowel dysmotility and colon shortening. CPW prevented the increase in villi width, crypt depth, and mucosal thickness in the duodenum, but not in the colon. Preservation of mucus, reduction of oxidative stress, inflammation, and prevention of the 5-FU-induced enlargement and swelling of the spleen were observed. In conclusion, this study demonstrated for the first time that CPW alleviates the intestinal damage induced by 5-FU and could be used as an adjuvant strategy during chemotherapy.


Assuntos
Fluoruracila , Mucosite , Camundongos , Animais , Fluoruracila/toxicidade , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Mucosite/prevenção & controle , Antimetabólitos Antineoplásicos/toxicidade , Mucosa Intestinal , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Polissacarídeos/farmacologia
4.
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
5.
Br J Haematol ; 198(5): 866-874, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35799423

RESUMO

Nucleophosmin1 (NPM1) is one of the most commonly mutated genes in AML and is often associated with a favourable prognosis. Immune responses play an increasing role in AML treatment decisions; however, the role of immune checkpoint inhibition is still not clear. To address this, we investigated specific immune responses against NPM1, and three other leukaemia-associated antigens (LAA), PRAME, Wilms' tumour 1 and RHAMM in AML patients. We investigated T cell responses against leukaemic progenitor/stem cells (LPC/LSC) using colony-forming immunoassays and flow cytometry. We examined whether immune checkpoint inhibition with the anti-programmed death 1 antibody increases the immune response against stem cell-like cells, comparing cells from NPM1 mutated and NPM1 wild-type AML patients. We found that the anti-PD-1 antibody, nivolumab, increases LAA stimulated cytotoxic T lymphocytes and the cytotoxic effect against LPC/LSC. The effect was strongest against NPM1mut cells when the immunogenic epitope was derived from the mutated region of NPM1 and these effects were enhanced through the addition of anti-PD-1. The data suggest that patients with NPM1 mutated AML could be treated with the immune checkpoint inhibitor anti-PD-1 and that this treatment combined with NPM1-mutation specific directed immunotherapy could be even more effective for this unique group of patients.


Assuntos
Inibidores de Checkpoint Imunológico , Leucemia Mieloide Aguda , Nucleofosmina , Linfócitos T Citotóxicos , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Imunidade , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Mutação , Nivolumabe/farmacologia , Nucleofosmina/genética , Receptor de Morte Celular Programada 1/antagonistas & inibidores
6.
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
7.
Food Res Int ; 156: 111291, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35651057

RESUMO

Inflammatory bowel disease (IBD) includes two distinct diseases: Crohn's disease (CD) and ulcerative colitis (UC). IBD is a chronic systemic disease of the gastrointestinal tract, characterized by an inflammatory process. The mechanisms by which diseases develop are still unknown, but it is known that it results from a complex interaction between genetic variability, the host's immune system, and environmental factors. One of the main complaints of patients is abdominal pain, which may be associated with the release of inflammatory mediators, changes in the normal motility of the digestive tract, and increased intestinal permeability. Currently available drugs for abdominal pain are not satisfactory, therefore, it is extremely necessary to seek new therapeutic options for the treatment of abdominal pain. Polysaccharides extracted from fruits have attracted interest, as these molecules protect the intestinal mucosa and promote wound healing, attenuating inflammation, pain, and altered intestinal motility. In this study, we investigated the ability of pectic polysaccharides obtained from guavira pomace, named CPW to reduce visceral hypersensitivity, regulate intestinal motility, and control diarrhea in mice. Acetic acid, capsaicin, or mustard oil were used to assess visceral pain in normal mice. CPW reduced abdominal writhing, cell migration, and capsaicin-induced visceral nociception. Furthermore, it regulated intestinal motility and all measured parameters of castor oil-induced diarrhea. CPW treatment reversed the increase in mucosal permeability, TEER, and tissue weight caused by acetic acid. In addition, molecular docking analysis showed that specific the CPW units binds to the 3N8V, 5COX, 2J67 and 6RBF proteins. Thus, the results suggest that CPW has attractive therapeutic characteristics for the treatment of abdominal pain and ulcerative colitis.


Assuntos
Colite Ulcerativa , Doenças Inflamatórias Intestinais , Dor Abdominal/tratamento farmacológico , Animais , Capsaicina , Colite Ulcerativa/tratamento farmacológico , Diarreia , Carboidratos da Dieta , Frutas , Humanos , Camundongos , Simulação de Acoplamento Molecular , Polissacarídeos/farmacologia
8.
Front Pharmacol ; 12: 722889, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447313

RESUMO

The solute carrier (SLC) superfamily represents the biggest family of transporters with important roles in health and disease. Despite being attractive and druggable targets, the majority of SLCs remains understudied. One major hurdle in research on SLCs is the lack of tools, such as cell-based assays to investigate their biological role and for drug discovery. Another challenge is the disperse and anecdotal information on assay strategies that are suitable for SLCs. This review provides a comprehensive overview of state-of-the-art cellular assay technologies for SLC research and discusses relevant SLC characteristics enabling the choice of an optimal assay technology. The Innovative Medicines Initiative consortium RESOLUTE intends to accelerate research on SLCs by providing the scientific community with high-quality reagents, assay technologies and data sets, and to ultimately unlock SLCs for drug discovery.

9.
PeerJ ; 9: e11461, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249482

RESUMO

BACKGROUND: Sugarcane is a crop of global importance and has been expanding to areas with soils containing high levels of exchangeable aluminum (Al), which is a limiting factor for crop development in acidic soils. The study of the sugarcane physiological and nutritional behavior together with patterns of gene expression in response to Al stress may provide a basis for effective strategies to increase crop productivity in acidic soils. METHODS: Sugarcane cultivars were evaluated for physiological parameters (photosynthesis, stomatal conductance, and transpiration), nutrient (N, P, K, Ca, Mg, and S) and Al contents in leaves and roots and gene expression, of the genes MDH, SDH by qPCR, both related to the production of organic acids, and SOD, related to oxidative stress. RESULTS: Brazilian sugarcane RB867515, RB928064, and RB935744 cultivars exhibited very different responses to induced stress by Al. Exposure to Al caused up-regulation (SOD and MDH) or down-regulation (SDH, MDH, and SOD), depending on the cultivar, Al level, and plant tissue. The RB867515 cultivar was the most Al-tolerant, showing no decline of nutrient content in plant tissue, photosynthesis, transpiration, and stomatal conductance after exposure to Al; it exhibited the highest Al content in the roots, and showed important MDH and SOD gene expression in the roots. RB928064 only showed low expression of SOD in roots and leaves, while RB935744 showed important expression of the SOD gene only in the leaves. Sugarcane cultivars were classified in the following descending Al-tolerance order: RB867515 > RB928064 = RB935744. These results may contribute to the obtention of Al-tolerant cultivars that can play their genetic potential in soils of low fertility and with low demand for agricultural inputs; the selection of potential plants for breeding programs; the elucidation of Al detoxification mechanisms employed by sugarcane cultivars.

10.
Medicina (B.Aires) ; 81(2): 257-268, June 2021. graf
Artigo em Espanhol | LILACS | ID: biblio-1287278

RESUMO

Resumen La transmisión vertical de la infección por Toxoplasma gondii ocurre cuando la madre se infecta por primera vez en el transcurso del embarazo. El diagnóstico de la infección materna y la del re cién nacido se logra con el conjunto de pruebas serológicas, hallazgos clínicos y ecográficos. El reconocimiento temprano de la infección materna permite un tratamiento que reduce la tasa de transmisión y el riesgo de daño en el producto de la concepción. El objetivo de este consenso de expertos fue revisar la literatura científica para actualizar las recomendaciones de práctica clínica respecto de la prevención, el diagnóstico y el tratamiento de la toxoplasmosis congénita en nuestro país.


Abstract Mother-to-child transmission in Toxoplasma gondii infection occurs only when the infection is acquired for the first time during pregnancy. Diag nosis of maternal infection and the newborn is achieved by a combination of serological tests, clinical features and ultrasound images. An early diagnosis of maternal infection allows treatment that offers a reduction both in transmission rate and risk of congenital damage. The aim of this expert consensus was to review the scientific literature which would enable an update of the clinical practice guideline of prevention, diagnosis and treatment of congenital toxoplasmosis in our country.


Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Criança , Toxoplasma , Toxoplasmose , Toxoplasmose Congênita/diagnóstico , Toxoplasmose Congênita/prevenção & controle , Toxoplasmose Congênita/tratamento farmacológico , Complicações Parasitárias na Gravidez , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Consenso , Anamnese
11.
Medicina (B Aires) ; 81(2): 257-268, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33906145

RESUMO

Mother-to-child transmission in Toxoplasma gondii infection occurs only when the infection is acquired for the first time during pregnancy. Diagnosis of maternal infection and the newborn is achieved by a combination of serological tests, clinical features and ultrasound images. An early diagnosis of maternal infection allows treatment that offers a reduction both in transmission rate and risk of congenital damage. The aim of this expert consensus was to review the scientific literature which would enable an update of the clinical practice guideline of prevention, diagnosis and treatment of congenital toxoplasmosis in our country.


La transmisión vertical de la infección por Toxoplasma gondii ocurre cuando la madre se infecta por primera vez en el transcurso del embarazo. El diagnóstico de la infección materna y la del recién nacido se logra con el conjunto de pruebas serológicas, hallazgos clínicos y ecográficos. El reconocimiento temprano de la infección materna permite un tratamiento que reduce la tasa de transmisión y el riesgo de daño en el producto de la concepción. El objetivo de este consenso de expertos fue revisar la literatura científica para actualizar las recomendaciones de práctica clínica respecto de la prevención, el diagnóstico y el tratamiento de la toxoplasmosis congénita en nuestro país.


Assuntos
Complicações Parasitárias na Gravidez , Toxoplasma , Toxoplasmose Congênita , Toxoplasmose , Criança , Consenso , Feminino , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Anamnese , Gravidez , Toxoplasmose Congênita/diagnóstico , Toxoplasmose Congênita/tratamento farmacológico , Toxoplasmose Congênita/prevenção & controle
12.
Histochem Cell Biol ; 155(1): 75-88, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33108533

RESUMO

Obesity due to high calorie intake induces cardiac hypertrophy and dysfunction, thus contributing to cardiovascular morbidity and mortality. Recent studies in aging suggest that oral supplementation with the natural polyamine spermidine has a cardioprotective effect. Here, the hypothesis was tested that spermidine or voluntary activity alone or in combination protect the heart from adverse effects induced by obesity. Therefore, C57Bl/6 mice (n = 8-10 per group) were subjected to control or high fat diet (HFD) and were left untreated, or either received spermidine via drinking water or were voluntarily active or both. After 30 weeks, the mice were killed and the left ventricle of the hearts was processed for light and electron microscopy. Design-based stereology was used to estimate parameters of hypertrophy, fibrosis, and lipid accumulation. HFD induced cardiac hypertrophy as demonstrated by higher volumes of the left ventricle, cardiomyocytes, interstitium, myofibrils and cardiomyocyte mitochondria. These changes were not influenced by spermidine or voluntary activity. HFD also induced myocardial fibrosis and accumulation of lipid droplets within cardiomyocytes. These HFD effects were enhanced in spermidine treated animals but not in voluntarily active mice. This was even the case in voluntarily active mice that received spermidine. In conclusion, the data confirm the induction of left ventricular hypertrophy by high-fat diet and suggest that-under high fat diet-spermidine enhances cardiomyocyte lipid accumulation and interstitial fibrosis which is counteracted by voluntary activity.


Assuntos
Cardiomegalia/metabolismo , Fibrose/metabolismo , Hipertrofia Ventricular Esquerda/metabolismo , Gotículas Lipídicas/metabolismo , Miócitos Cardíacos/metabolismo , Obesidade/metabolismo , Administração Oral , Animais , Cardiomegalia/induzido quimicamente , Cardiomegalia/patologia , Dieta Hiperlipídica/efeitos adversos , Fibrose/induzido quimicamente , Fibrose/patologia , Hipertrofia Ventricular Esquerda/induzido quimicamente , Hipertrofia Ventricular Esquerda/patologia , Gotículas Lipídicas/patologia , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Miócitos Cardíacos/patologia , Obesidade/induzido quimicamente , Obesidade/patologia , Espermidina/administração & dosagem
13.
Eur J Immunol ; 51(1): 250-252, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32761616

RESUMO

In mouse myocardial infarction, we combined lineage tracing of cardiac macrophages, mapping their ontogeny, with an analysis of their phenotype and phagocytic functions. While embryo-derived macrophages were most abundant in homeostasis, bone marrow-derived MHC-IIlo macrophages increased in both numbers and phagocytic capacity to clear necrotic cardiomyocytes early after ischemia/perfusion injury.


Assuntos
Antígenos de Histocompatibilidade Classe II/metabolismo , Macrófagos/imunologia , Infarto do Miocárdio/imunologia , Miocárdio/imunologia , Animais , Receptor 1 de Quimiocina CX3C/metabolismo , Modelos Animais de Doenças , Embrião de Mamíferos/citologia , Embrião de Mamíferos/imunologia , Macrófagos/patologia , Camundongos , Camundongos Transgênicos , Infarto do Miocárdio/patologia , Miocárdio/patologia , Miócitos Cardíacos/imunologia , Miócitos Cardíacos/patologia , Fagocitose/imunologia
14.
Nat Commun ; 11(1): 4549, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917889

RESUMO

Arterial macrophages have different developmental origins, but the association of macrophage ontogeny with their phenotypes and functions in adulthood is still unclear. Here, we combine macrophage fate-mapping analysis with single-cell RNA sequencing to establish their cellular identity during homeostasis, and in response to angiotensin-II (AngII)-induced arterial inflammation. Yolk sac erythro-myeloid progenitors (EMP) contribute substantially to adventitial macrophages and give rise to a defined cluster of resident immune cells with homeostatic functions that is stable in adult mice, but declines in numbers during ageing and is not replenished by bone marrow (BM)-derived macrophages. In response to AngII inflammation, increase in adventitial macrophages is driven by recruitment of BM monocytes, while EMP-derived macrophages proliferate locally and provide a distinct transcriptional response that is linked to tissue regeneration. Our findings thus contribute to the understanding of macrophage heterogeneity, and associate macrophage ontogeny with distinct functions in health and disease.


Assuntos
Artérias/citologia , Arterite/imunologia , Diferenciação Celular/fisiologia , Homeostase/fisiologia , Macrófagos/fisiologia , Envelhecimento/fisiologia , Angiotensina II/administração & dosagem , Angiotensina II/imunologia , Animais , Artérias/fisiologia , Medula Óssea/fisiologia , Transplante de Medula Óssea , Linhagem da Célula , Modelos Animais de Doenças , Feminino , Células-Tronco Hematopoéticas/fisiologia , Humanos , Masculino , Camundongos , Camundongos Transgênicos , RNA-Seq , Regeneração/fisiologia , Análise de Célula Única , Quimeras de Transplante
15.
Int J Biol Macromol ; 158: 375-383, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32360970

RESUMO

Huanglongbing (HLB) is a devastating citrus disease associated with Candidatus Liberibacter asiaticus (CLas) and is transmitted by the psyllid Diaphorina citri Kuwayama. Diaphorina citri belongs to Hemiptera order, which has cysteine peptidases as the most abundant proteolytic enzymes present in digestive tract. As cysteine peptidases are involved in different insect development processes, this class of enzymes has acquired biotechnological importance. In this context, we identified a cathepsin L-like (DCcathL1) from the Diaphorina citri transcriptome database and expressed the enzyme in E. coli. Quantitative real-time RT-PCR was conducted to determine DCcathL1 gene expression in different parts and developmental phases of the insect. We observed that DCcathL1 expression in the gut was 2.59 and 2.87-fold higher than in the head and carcass, respectively. Furthermore, DCcathL1 expression was greater in eggs than in nymphs and adults, suggesting a putative role of the enzyme in the embryonic development. In addition, enzymatic inhibitory activity using four recombinant Citrus cystatins were performed. Among them, CsinCPI-2 was the strongest DCcathL1 inhibitor with a Ki value of 0.005 nM. Our results may contribute in the development of strategies for D. citri control, such as silencing the DCcathL1 gene and the use of transgenic plants that overexpress peptidase inhibitors.

16.
Food Res Int ; 132: 109065, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32331640

RESUMO

Exotic fruits and their co-products may be valuable sources of antioxidant dietary fibres (DF) which are useful for food industry and human health. In this study, we aimed to characterize DF obtained from guavira fruit pomace and investigate its antioxidant potential employing TEAC assay as well as a cell model. The DF were chemically characterized as containing arabinan, highly-methoxylated homogalacturonan and arabinogalactan. The DF-containing fraction (CPW) presented ABTS free radical scavenger activity. MTT and DCFH-DA assay were performed to assess, respectively, changes in cell viability and the potential intracellular antioxidant activity against H2O2-induced oxidative stress in murine NIH 3T3 fibroblast. CPW exhibited no effects on cell viability, moreover, when administered 48 h prior the induction of H2O2 toxic effects, it protected the cells, significantly increasing the cell viability compared to control. This protection may be related to the observed reduction of reactive oxygen species levels. Thus, the pre-treatment of cells with guavira DF for 48 h remarkably induced a cytoprotection against pro-oxidant conditions, and may be a valuable functional compound recovered from an unexploited agroindutrial waste.


Assuntos
Antioxidantes/análise , Antioxidantes/farmacologia , Fibras na Dieta/análise , Frutas/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Galactanos/química , Peróxido de Hidrogênio/toxicidade , Camundongos , Células NIH 3T3 , Estresse Oxidativo , Pectinas/química , Polissacarídeos/química
17.
Int J Biol Macromol ; 152: 546-553, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32109474

RESUMO

Phytocystatins are plant cystatins that are related to several physiological processes regulating endogenous cysteine proteases involved in seed development and germination, programmed cell death and response to stress conditions. In addition, phytocystatins can act in plant defense against exogenous peptidases from herbivorous insects, pathogens and nematodes. Considering that Citrus fruits are important to human nutrition and represent a high value crop in worldwide agriculture, in the present work, we performed the identification of putative cystatins from Citrus sinensis and from Citrus clementine and submitted them to phylogenetic analysis. Six cystatins from each species were identified as orthologous and classified into three well supported phylogenetic groups. Five cystatins representative of the phylogenetic groups were recombinantly expressed and the in vitro studies revealed them to be potent inhibitors against the cysteine peptidases papain, legumain, human cathepsins (B, L, S, K) and a cathepsin B-like from Diaphorina citri (the Asian Citrus psyllid). Our findings provide the C. clementina and C. sinensis cystatins classification and an enzyme-inhibitor interactions profile, which may reflect an evolutionary process of Citrus cystatins related to gene functions as initial germination rates and seedlings development as well associated to plant defense against pathogens, as insects and nematodes.


Assuntos
Citrus sinensis/genética , Citrus/genética , Cistatinas/metabolismo , Proteínas de Plantas/metabolismo , Animais , Biotecnologia , Catepsinas/antagonistas & inibidores , Citrus/metabolismo , Citrus sinensis/metabolismo , Simulação por Computador , Cistatinas/genética , Inibidores de Cisteína Proteinase , Germinação , Humanos , Cinética , Funções Verossimilhança , Nematoides , Filogenia , Proteínas de Plantas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sementes/metabolismo
18.
Cancer Immunol Immunother ; 69(4): 629-640, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32020256

RESUMO

The efficacy of immunotherapies in cancer treatment becomes more and more apparent not only in different solid tumors but also in hematological malignancies. However, in acute myeloid leukemia (AML), mechanisms to increase the efficacy of immunotherapeutic approaches have to be further elucidated. Targeting leukemic progenitor and stem cells (LPC/LSC) by specific CTL, for instance, in an adjuvant setting or in minimal residual disease, might be an option to prevent relapse of AML or to treat MRD. Therefore, we investigated the influence of immune checkpoint inhibitors on LAA-specific immune responses by CTL against leukemic myeloid blasts and colony-forming cells including leukemic progenitor cells (CFC/LPC). In functional immunoassays like CFU/CFI (colony-forming units/immunoassays) and ELISpot analysis, we detected specific LAA-directed immune responses against CFC/LPC that are postulated to be the source population of relapse of the disease. The addition of nivolumab (anti-PD-1) significantly increases LAA-directed immune responses against CFC/LPC, no effect is seen when ipilimumab (anti-CTLA-4) is added. The combination of ipilimumab and nivolumab does not improve the effect compared to nivolumab alone. The anti-PD1-directed immune response correlates to PD-L1 expression on progenitor cells. Our data suggest that immunotherapeutic approaches have the potential to target malignant CFC/LPC and anti-PD-1 antibodies could be an immunotherapeutic approach in AML. Moreover, combination with LAA-directed vaccination strategies might also open interesting application possibilities.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ipilimumab/uso terapêutico , Leucemia Mieloide/terapia , Células-Tronco Neoplásicas/efeitos dos fármacos , Nivolumabe/uso terapêutico , Linfócitos T/imunologia , Doença Aguda , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Antígeno CTLA-4/metabolismo , Humanos , Imunoterapia/métodos , Ipilimumab/administração & dosagem , Leucemia Mieloide/imunologia , Leucemia Mieloide/metabolismo , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/metabolismo , Nivolumabe/administração & dosagem , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Resultado do Tratamento
19.
Sci Rep ; 9(1): 14965, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628369

RESUMO

Multi-angle light scattering coupled with size-exclusion chromatography (SEC-MALS) is a standard approach for protein characterization. Recently MALS detection has been coupled with ion-exchange chromatography (IEX) which demonstrated the feasibility and high value of MALS in combination with non-sized-based fractionation methods. In this study we coupled reverse-phase ultra-high pressure liquid chromatography (RP-UPLC) with a low-dispersion MALS detector for the characterization of intact monoclonal antibody (mAbs) and their fragments. We confirmed a constant refractive index increment value for mAbs in RP gradients, in good agreement with the values in literature for other classes of proteins. We showed that the impurities eluting from a RP column can often be related to aggregated species and we confirmed that in most cases those oligomers are present also in SEC-MALS. Yet, in few cases small aggregates fractions in RP-UPLC are an artifact. In fact, proteins presenting thermal and physical stability not suitable for the harsh condition applied during the RP separation of mAbs (i.e. organic solvents at high temperature) can aggregate. Further, we applied RP-UPLC-MALS during a long term stability studies. The different principle of separation used in RP-UPLC- MALS provides an additional critical level of protein characterization compared to SEC-MALS and IEX-MALS.


Assuntos
Anticorpos Monoclonais/química , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Humanos , Concentração de Íons de Hidrogênio , Luz , Peso Molecular , Peptídeos/química , Refratometria , Espalhamento de Radiação , Temperatura
20.
Virchows Arch ; 475(6): 789-794, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31338587

RESUMO

Acinar cell carcinomas (ACCs) of the pancreas are a heterogeneous group of neoplasms showing a wide spectrum of morphological features including acinar, solid, glandular, and trabecular architecture. In addition, uncommon cytological aspects have recently been described and include oncocytic, spindle, clear, and pleomorphic cell types. This wide histological spectrum represents a challenge in the diagnostic task for pathologists. Molecular mechanisms involved in the onset and progression of ACCs are not completely known, but, in general, they differ from those observed in ductal adenocarcinomas or neuroendocrine neoplasms of the pancreas and frequently include alterations in the APC/ß-catenin pathway. In the present paper, we describe a new variant of ACC showing thyroid-like follicular features and CTNNB1 mutation. This phenotype needs to be included in the spectrum of morphological presentation of ACC.


Assuntos
Carcinoma de Células Acinares/patologia , Neoplasias Pancreáticas/patologia , Glândula Tireoide/patologia , beta Catenina/genética , Carcinoma de Células Acinares/diagnóstico , Carcinoma de Células Acinares/genética , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Neoplasias Pancreáticas/diagnóstico , beta Catenina/metabolismo
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