Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Gut ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740509

RESUMO

OBJECTIVE: To decipher the mechanisms by which the major human milk oligosaccharide (HMO), 2'-fucosyllactose (2'FL), can affect body weight and fat mass gain on high-fat diet (HFD) feeding in mice. We wanted to elucidate whether 2'FL metabolic effects are linked with changes in intestinal mucus production and secretion, mucin glycosylation and degradation, as well as with the modulation of the gut microbiota, faecal proteome and endocannabinoid (eCB) system. RESULTS: 2'FL supplementation reduced HFD-induced obesity and glucose intolerance. These effects were accompanied by several changes in the intestinal mucus layer, including mucus production and composition, and gene expression of secreted and transmembrane mucins, glycosyltransferases and genes involved in mucus secretion. In addition, 2'FL increased bacterial glycosyl hydrolases involved in mucin glycan degradation. These changes were linked to a significant increase and predominance of bacterial genera Akkermansia and Bacteroides, different faecal proteome profile (with an upregulation of proteins involved in carbon, amino acids and fat metabolism and a downregulation of proteins involved in protein digestion and absorption) and, finally, to changes in the eCB system. We also investigated faecal proteomes from lean and obese humans and found similar changes observed comparing lean and obese mice. CONCLUSION: Our results show that the HMO 2'FL influences host metabolism by modulating the mucus layer, gut microbiota and eCB system and propose the mucus layer as a new potential target for the prevention of obesity and related disorders.

2.
J Biol Chem ; 299(11): 105335, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37827291

RESUMO

Hepatoma-derived growth factor (HDGF) overexpression and uncontrolled reactive oxygen species (ROS) accumulation are involved in malignant transformation and poor prognosis in various types of cancer. However, the interplay between HDGF and ROS generation has not been elucidated in hepatocellular carcinoma. Here, we first analyzed the profile of HDGF expression and ROS production in newly generated orthotopic hepatomas by ultrasound-guided implantation. In situ superoxide detection showed that HDGF-overexpressing hepatomas had significantly elevated ROS levels compared with adjacent nontumor tissues. Consistently, liver tissues from HDGF-deficient mice exhibited lower ROS fluorescence than those from age- and sex-matched WT mice. ROS-detecting fluorescent dyes and flow cytometry revealed that recombinant HDGF (rHDGF) stimulated the production of superoxide anion, hydrogen peroxide, and mitochondrial ROS generation in cultured hepatoma cells in a dose-dependent manner. In contrast, the inactive Ser103Ala rHDGF mutant failed to promote ROS generation or oncogenic behaviors. Seahorse metabolic flux assays revealed that rHDGF dose dependently upregulated bioenergetics through enhanced basal and total oxygen consumption rate, extracellular acidification rate, and oxidative phosphorylation in hepatoma cells. Moreover, antioxidants of N-acetyl cysteine and MitoQ treatment significantly inhibited HDGF-mediated cell proliferation and invasive capacity. Genetic silencing of superoxide dismutase 2 augmented the HDGF-induced ROS generation and oncogenic behaviors of hepatoma cells. Finally, genetic knockdown nucleolin (NCL) and antibody neutralization of surface NCL, the HDGF receptor, abolished the HDGF-induced increase in ROS and mitochondrial energetics. In conclusion, this study has demonstrated for the first time that the HDGF/NCL signaling axis induces ROS generation by elevating ROS generation in mitochondria, thereby stimulating liver carcinogenesis.


Assuntos
Carcinoma Hepatocelular , Animais , Camundongos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Espécies Reativas de Oxigênio , Carcinogênese/genética
3.
Diabetologia ; 66(5): 913-930, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36692509

RESUMO

AIMS/HYPOTHESIS: The mitochondrial chaperonin heat shock protein (HSP) 60 is indispensable in protein folding and the mitochondrial stress response; however, its role in nutrient metabolism remains uncertain. This study investigated the role of HSP60 in diet-induced non-alcoholic fatty liver disease (NAFLD). METHODS: We studied human biopsies from individuals with NAFLD, murine high-fat-diet (HFD; a diet with 60% energy from fat)-induced obesity (DIO), transgenic (Tg) mice overexpressing Hsp60 (Hsp60-Tg), and human HepG2 cells transfected with HSP60 cDNA or with HSP60 siRNA. Histomorphometry was used to assess hepatic steatosis, biochemistry kits were used to measure insulin resistance and glucose tolerance, and an automated home cage phenotyping system was used to assess energy expenditure. Body fat was assessed using MRI. Macrophage infiltration, the lipid oxidation marker 4-hydroxy-2-nonenal (4-HNE) and the oxidative damage marker 8-hydroxy-2'-deoxyguanosine (8-OHdG) were detected using immunohistochemistry. Intracellular lipid droplets were evaluated by Nile red staining. Expression of HSP60, and markers of lipogenesis and fatty acid oxidation were quantified using RT-PCR and immunoblotting. Investigations were analysed using the two-way ANOVA test. RESULTS: Decreased HSP60 expression correlated with severe steatosis in human NAFLD biopsies and murine DIO. Hsp60-Tg mice developed less body fat, had reduced serum triglyceride levels, lower levels of insulin resistance and higher serum adiponectin levels than wild-type mice upon HFD feeding. Respiratory quotient profile indicated that fat in Hsp60-Tg mice may be metabolised to meet energy demands. Hsp60-Tg mice showed amelioration of HFD-mediated hepatic steatosis, M1/M2 macrophage dysregulation, and 4-HNE and 8-OHdG overproduction. Forced HSP60 expression reduced the mitochondrial unfolded protein response, while preserving mitochondrial respiratory complex activity and enhancing fatty acid oxidation. Furthermore, HSP60 knockdown enhanced intracellular lipid formation and loss of sirtuin 3 (SIRT3) signalling in HepG2 cells upon incubation with palmitic acid (PA). Forced HSP60 expression improved SIRT3 signalling and repressed PA-mediated intracellular lipid formation. SIRT3 inhibition compromised HSP60-induced promotion of AMP-activated protein kinase (AMPK) phosphorylation and peroxisome proliferator-activated receptor α (PPARα levels), while also decreasing levels of fatty acid oxidation markers. CONCLUSION/INTERPRETATION: Mitochondrial HSP60 promotes fatty acid oxidation while repressing mitochondrial stress and inflammation to ameliorate the development of NAFLD by preserving SIRT3 signalling. This study reveals the hepatoprotective effects of HSP60 and indicates that HSP60 could play a fundamental role in the development of therapeutics for NAFLD or type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Sirtuína 3 , Animais , Humanos , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos/metabolismo , Resistência à Insulina/genética , Metabolismo dos Lipídeos , Lipídeos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Sirtuína 3/genética , Sirtuína 3/metabolismo
4.
J Biol Chem ; 298(10): 102442, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36055405

RESUMO

Leukocyte cell-derived chemotaxin 2 (LECT2) acts as a tumor suppressor in hepatocellular carcinoma (HCC). However, the antineoplastic mechanism of LECT2, especially its influence on hepatic cancer stem cells (CSCs), remains largely unknown. In The Cancer Genome Atlas cohort, LECT2 mRNA expression was shown to be associated with stage, grade, recurrence, and overall survival in human HCC patients, and LECT2 expression was downregulated in hepatoma tissues compared with the adjacent nontumoral liver. Here, we show by immunofluorescence and immunoblot analyses that LECT2 was expressed at lower levels in tumors and in poorly differentiated HCC cell lines. Using functional assays, we also found LECT2 was capable of suppressing oncogenic behaviors such as cell proliferation, anchorage-independent growth, migration, invasiveness, and epithelial-mesenchymal transition in hepatoma cells. Moreover, we show exogenous LECT2 treatment inhibited CSC functions such as tumor sphere formation and drug efflux. Simultaneously, hepatic CSC marker expression was also downregulated, including expression of CD133 and CD44. This was supported by infection with adenovirus encoding LECT2 (Ad-LECT2) in HCC cells. Furthermore, in animal experiments, Ad-LECT2 gene therapy showed potent efficacy in treating HCC. We demonstrate LECT2 overexpression significantly promoted cell apoptosis and reduced neovascularization/CSC expansion in rat hepatoma tissues. Mechanistically, we showed using immunoblot and immunofluorescence analyses that LECT2 inhibited ß-catenin signaling via the suppression of the hepatocyte growth factor/c-MET axis to diminish CSC properties in HCC cells. In summary, we reveal novel functions of LECT2 in the suppression of hepatic CSCs, suggesting a potential alternative strategy for HCC therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/terapia , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Neoplasias Hepáticas/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Ratos , Terapia Genética
5.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675163

RESUMO

Neuroblastoma (NB) is characterized by several malignant phenotypes that are difficult to treat effectively without combination therapy. The therapeutic implication of mitochondrial ClpXP protease ClpP and ClpX has been verified in several malignancies, but is unknown in NB. Firstly, we observed a significant increase in ClpP and ClpX expression in immature and mature ganglion cells as compared to more malignant neuroblasts and less malignant Schwannian-stroma-dominant cell types in human neuroblastoma tissues. We used ONC201 targeting ClpXP to treat NB cells, and found a significant suppression of mitochondrial protease, i.e., ClpP and ClpX, expression and downregulation of mitochondrial respiratory chain subunits SDHB and NDUFS1. The latter was associated with a state of energy depletion, increased reactive oxygen species, and decreased mitochondrial membrane potential, consequently promoting apoptosis and suppressing cell growth of NB. Treatment of NB cells with ONC201 as well as the genetic attenuation of ClpP and ClpX through specific short interfering RNA (siRNA) resulted in the significant upregulation of the tumor suppressor alpha thalassemia/mental retardation X-linked (ATRX) and promotion of neurite outgrowth, implicating mitochondrial ClpXP proteases in MYCN-amplified NB cell differentiation. Furthermore, ONC201 treatment significantly decreased MYCN protein expression and suppressed tumor formation with the reactivation of ATRX expression in MYCN-amplified NB-cell-derived xenograft tumors. Taken together, ONC201 could be the potential agent to provide diversified therapeutic application in NB, particularly in NB with MYCN amplification.


Assuntos
Deficiência Intelectual , Neuroblastoma , Talassemia alfa , Humanos , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Linhagem Celular Tumoral , Deficiência Intelectual/genética , Talassemia alfa/genética , Neuroblastoma/metabolismo , Mitocôndrias/metabolismo , Peptídeo Hidrolases/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteína Nuclear Ligada ao X/genética , Proteína Nuclear Ligada ao X/metabolismo
6.
FASEB J ; 34(12): 16163-16178, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33063394

RESUMO

Hepatitis is an important health problem worldwide. Novel molecular targets are in demand for detection and management of hepatitis. Hepatoma-derived growth factor (HDGF) has been delineated to participate in hepatic fibrosis and liver carcinogenesis. However, the relationship between hepatitis and HDGF remains unclear. This study aimed to elucidate the role of HDGF during hepatitis using concanavalin A (ConA)-induced hepatitis model. In cultured hepatocytes, ConA treatment-elicited HDGF upregulation at transcriptional level and promoted HDGF secretion while reducing intracellular HDGF protein level and cellular viability. Similarly, mice receiving ConA administration exhibited reduced hepatic HDGF expression and elevated circulating HDGF level, which was positively correlated with serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. By using HDGF knockout (KO) mice, it was found the ConA-evoked cell death was prominently alleviated in KO compared with control. Besides, it was delineated HDGF ablation conferred protection by suppressing the ConA-induced neutrophils recruitment in livers. Above all, the ConA-mediated activation of tumor necrosis factor-α (TNF-α)/interleukin-1ß (IL-1ß)/interleukin-6 (IL-6)/cyclooxygenase-2 (COX-2) inflammatory signaling was significantly abrogated in KO mice. Treatment with recombinant HDGF (rHDGF) dose-dependently stimulated the expression of TNF-α/IL-1ß/IL-6/COX-2 in hepatocytes, further supporting the pro-inflammatory function of HDGF. Finally, application of HDGF antibody not only attenuated the ConA-mediated inflammatory cascade in hepatocytes, but also ameliorated the ConA-induced hepatic necrosis and AST elevation in mice. In summary, HDGF participates in ConA-induced hepatitis via neutrophils recruitment and may constitute a therapeutic target for acute hepatitis.


Assuntos
Concanavalina A/farmacologia , Hepatite Animal/induzido quimicamente , Hepatite Animal/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos
7.
Int J Mol Sci ; 21(21)2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33114317

RESUMO

Melanoma is notoriously resistant to current cancer therapy. However, the chemoresistance mechanism of melanoma remains unclear. The present study unveiled that chemotherapy drug cisplatin induced the formation of giant cells, which exhibited enlargement in cell diameter and nucleus in mice and human melanoma cells. Giant cells were positive with melanoma maker S100 and cancer stem cell markers including ABCB5 and CD133 in vitro and in vivo. Moreover, giant cells retained the mitotic ability with expression of proliferation marker Ki-67 and exhibited multiple drug resistance to doxorubicin and actinomycin D. The mitochondria genesis/activities and cellular ATP level were significantly elevated in giant cells, implicating the demand for energy supply. Application of metabolic blockers such as sodium azide or 2-deoxy glucose abolished the cisplatin-induced giant cells formation and expression of cancer stemness markers. The present study unveils a novel chemoresistance mechanism of melanoma cells via size alteration and the anti-neoplastic strategy by targeting giant cells.


Assuntos
Trifosfato de Adenosina/metabolismo , Cisplatino/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Células Gigantes/patologia , Melanoma/tratamento farmacológico , Antígeno AC133/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Linhagem Celular Tumoral , Cisplatino/farmacologia , Desoxiglucose/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Gigantes/efeitos dos fármacos , Células Gigantes/metabolismo , Humanos , Antígeno Ki-67/metabolismo , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Proteínas S100/metabolismo , Azida Sódica/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Int J Mol Sci ; 21(2)2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31968661

RESUMO

Melanotan II (MTII), a synthetic analogue of the alpha-melanocyte stimulating hormone (α-MSH), has been applied for skin tanning in humans. However, the carcinogenic consequence of topical MTII has been equivocal. This study aims to delineate the anti-neoplastic efficacy and mechanism of MTII using the B16-F10 melanoma model in vitro and in vivo. It was found that, despite a lack of influence on proliferation, MTII potently inhibited the migration, invasion, and colony-forming capability of melanoma cells. Moreover, topical MTII application significantly attenuated the tumor progression in mice bearing established melanoma. Histological analysis revealed that MTII therapy induced apoptosis while inhibiting the proliferation and neovaluarization in melanoma tissues. By immunoblot and immunohistochemical analysis, it was found that MTII dose-dependently increased the phosphatase and tensin homolog (PTEN) protein level while reducing PTEN phosphorylation, which resulted in the inhibition of AKT/nuclear factor kappa B (NFκB) signaling. Consistently, MTII treatment inhibited cyclooxygenase II (COX-2) expression and prostaglandin E2 (PGE2) production in melanoma cells. Finally, studies of antibody neutralization suggest that the melanocortin 1 receptor (MC1R) plays a critical role in MTII-induced PTEN upregulation and melanoma suppression. Together, these results indicate that MTII elicits PTEN upregulation via MC1R, thereby suppressing melanoma progression through downregulating COX-2/PGE2 signaling. Hence, topical MTII therapy may facilitate a novel therapeutic strategy against melanoma.


Assuntos
Antineoplásicos/administração & dosagem , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Ciclo-Oxigenase 2/metabolismo , Melanoma Experimental/tratamento farmacológico , PTEN Fosfo-Hidrolase/metabolismo , Peptídeos Cíclicos/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , alfa-MSH/análogos & derivados , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Dinoprostona/genética , Dinoprostona/metabolismo , Humanos , Imuno-Histoquímica , Melanoma Experimental/metabolismo , Camundongos , Modelos Biológicos , PTEN Fosfo-Hidrolase/genética , Fosforilação , Receptor Tipo 1 de Melanocortina/genética , Receptor Tipo 1 de Melanocortina/metabolismo , Regulação para Cima/efeitos dos fármacos , alfa-MSH/administração & dosagem
9.
BMC Cancer ; 19(1): 1083, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711427

RESUMO

BACKGROUND: Hepatoma-derived growth factor (HDGF) participates in angiogenesis and represents a negative prognostic factor in oral cancer. The current study was designed to elucidate the regulatory mechanism between HDGF and vascular endothelial growth factor (VEGF) and the clinical impact of oral cancer. METHODS: TCGA data and surgical samples from oral cancer patients were used for the clinicopathological parameter and survival analysis. Human oral cancer SCC4 and SAS cells were treated with recombinant HDGF protein. VEGF gene expression and protein level were analyzed by RT-PCR, Western blotting, and enzyme-linked immunosorbent assay. The signaling pathways for regulating VEGF expression were investigated. The nucleolin neutralizing antibody and HIF-1α inhibitor were applied to SCC4 cells to investigate their effects on the HDGF-stimulated VEGF pathways. RESULTS: TCGA and immunohistochemical analysis revealed a positive correlation between HDGF and VEGF expression in oral cancer tissues. Recombinant HDGF significantly increased VEGF gene and protein expression in oral cancer SCC4 cells in a dose-dependent manner. HDGF enhanced the phosphorylation levels of AKT and IkB and the protein level of HIF-1α and NF-κB. The nucleolin-neutralizing antibody abolished HDGF-stimulated HIF-1α, NF-κB and VEGF protein expression in SCC4 cells. The HIF-1α inhibitor antagonized the HDGF-induced VEGF gene expression. High VEGF expression was strongly correlated with HDGF expression, advanced disease, and poor survival. CONCLUSION: This study postulated a new pathway in which HDGF activated HIF-1α and then induced VEGF expression through binding to membrane nucleolin under normoxic conditions, leading to poor disease control. The HDGF/HIF-1α/VEGF axis is important for developing future therapeutic strategies.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Bucais/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Masculino , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Prognóstico , Proteínas Recombinantes/farmacologia , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Fator A de Crescimento do Endotélio Vascular/genética
10.
Int J Mol Sci ; 19(12)2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30513637

RESUMO

α-melanocyte-stimulating hormone (α-MSH) has been characterized as a novel angiogenesis inhibitor. The homeostasis of nitric oxide (NO) plays an important role in neovascularization. However, it remains unclear whether α-MSH mitigates angiogenesis through modulation of NO and its signaling pathway. The present study elucidated the function and mechanism of NO signaling in α-MSH-induced angiogenesis inhibition using cultured human umbilical vein endothelial cells (HUVECs), rat aorta rings, and transgenic zebrafish. By Griess reagent assay, it was found α-MSH dose-dependently reduced the NO release in HUVECs. Immunoblotting and immunofluorescence analysis revealed α-MSH potently suppressed endothelial and inducible nitric oxide synthase (eNOS/iNOS) expression, which was accompanied with inhibition of nuclear factor kappa B (NF-κB) activities. Excessive supply of NO donor l-arginine reversed the α-MSH-induced angiogenesis inhibition in vitro and in vivo. By using antibody neutralization and RNA interference, it was delineated that melanocortin-1 receptor (MC1-R) and melanocortin-2 receptor (MC2-R) participated in α-MSH-induced inhibition of NO production and NF-κB/eNOS/iNOS signaling. This was supported by pharmaceutical inhibition of protein kinase A (PKA), the downstream effector of MC-Rs signaling, using H89 abolished the α-MSH-mediated suppression of NO release and eNOS/iNOS protein level. Therefore, α-MSH exerts anti-angiogenic function by perturbing NO bioavailability and eNOS/iNOS expression in endothelial cells.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , NF-kappa B/metabolismo , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Receptores de Melanocortina/metabolismo , alfa-MSH/uso terapêutico , Células Endoteliais da Veia Umbilical Humana , Humanos , Óxido Nítrico , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos
11.
Prostate ; 76(16): 1469-1483, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27416770

RESUMO

BACKGROUND: Prostate cancer is one of the most prevalent cancers in men worldwide. Aberrant activation of c-Met/signal transducer and activator of transcription-3 (STAT3) signaling is involved in prostate carcinogenesis, underscoring the demand for developing c-Met/STAT3-targeting drugs. Thus, we first utilized virtual screening strategy to identify STAT3-inhibiting marine compound, heteronemin, and then validated the STAT3-inhibiting function of heteronemin in prostate cancer cells. METHODS: Human prostate cancer LNCaP, DU145, and PC-3 cell lines were treated with heteronemin for 24 hr, then the cell viability was evaluated by MTT assay. Flow cytometry was performed to analyze the apoptosis in heteronemin-treated cells. Western blot and quantitative real-time PCR were executed to further confirm the c-Met/STAT3 signaling inhibition by heteronemin in DU145 and PC-3 cells. RESULTS: In this study, we employed the virtual screening strategy to identify heteronemin, a spongean sesterterpene, as a potential STAT3 inhibitor from Taiwan marine drugs library. Application of heteronemin potently suppressed the viability and anchorage-independent growth of human prostate cancer cells. Besides, heteronemin induced apoptosis in prostate cancer cells by activation of both intrinsic (caspase-9) and extrinsic (caspase-8) apoptotic pathways. By luciferase assay and expression analysis, it was confirmed that heteronemin inhibited the phosphorylation of c-Met/src/STAT3 signaling axis, STAT3-driven luciferase activities and expression of STAT3-regulated genes including Bcl-xL, Bcl-2, and Cyclin D1. Finally, heteronemin effectively antagonized the hepatocyte growth factor (HGF)-stimulated c-Met/STAT3 activation as well as the proliferation and colonies formation in refractory prostate cancer cells. CONCLUSIONS: These findings suggest that heteronemin may constitute a novel c-Met/STAT3-targeting agent for prostate cancer. Prostate 76:1469-1483, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Fator de Transcrição STAT3/antagonistas & inibidores , Terpenos/farmacologia , Antineoplásicos , Apoptose/efeitos dos fármacos , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Masculino , Simulação de Acoplamento Molecular , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Serina Endopeptidases/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Terpenos/química , c-Mer Tirosina Quinase
12.
Biochim Biophys Acta ; 1840(6): 1850-60, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24530634

RESUMO

BACKGROUND: Gene therapy of proopiomelanocortin, the precursor of α-melanocyte-stimulating hormone (α-MSH), suppresses the neovascularization in tumors. However, the roles of α-MSH in angiogenesis remain unclear. METHODS: The influence of α-MSH on angiogenesis was evaluated by ex vivo rat aorta and in vivo, including transgenic zebrafish and chicken chorioallantoic membrane (CAM) assays. The effect of α-MSH on proliferation, matrix metalloproteinase (MMP) secretion, migration and tube formation was examined using human umbilical vein endothelial cells (HUVECs). The expression of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) was investigated by quantitative RT-PCR, immunoblot and immunofluorescent analysis. Antibodies' neutralization was employed to dissect the receptor(s) transmitting α-MSH signaling. RESULTS: Application of α-MSH potently suppressed the microvessels sprouting in organotypic aortic rings. Besides, α-MSH perturbed the vessels development in zebrafish and chicken embryos. α-MSH (0.01-10nM) inhibited the MMP-2 secretion, migration and tube formation of HUVECs without affecting proliferation. Mechanistic studies unveiled α-MSH decreased the VEGF expression and release in HUVECs. Besides, α-MSH downregulated the VEGFR2 expression at transcriptional and translational levels. Importantly, α-MSH attenuated the Akt phosphorylation, but enhanced the expression of PTEN, endogenous antagonist of PI3K/Akt signaling. Expression analysis and antibody neutralization revealed that MC1-R and MC2-R participated in α-MSH-induced blockage of migration and VEGF/VEGFR2/Akt signaling. However, VEGF supply failed to reverse the anti-angiogenic function of α-MSH. CONCLUSIONS: α-MSH inhibits the physiological angiogenesis by attenuating VEGF/VEGFR2/Akt signaling in endothelial cells. GENERAL SIGNIFICANCE: α-MSH is a potent angiogenesis inhibitor targeting at endothelial VEGF/VEGFR2 signaling, which may have potential for therapeutic application.


Assuntos
Inibidores da Angiogênese/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/fisiologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/fisiologia , alfa-MSH/farmacologia , Animais , Células Cultivadas , Humanos , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , PTEN Fosfo-Hidrolase/análise , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Melanocortina/fisiologia , Receptor Tipo 2 de Melanocortina/fisiologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Peixe-Zebra
13.
Biomed Pharmacother ; 174: 116561, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38593705

RESUMO

Pectin and its derivatives have been shown to modulate immune signaling as well as gut microbiota in preclinical studies, which may constitute the mechanisms by which supplementation of specific pectic polysaccharides confers protection against viral respiratory infections. In a double-blind, placebo-controlled rhinovirus (RV16) challenge study, healthy volunteers were randomized to consume placebo (0.0 g/day) (N = 46), low-dose (0.3 g/day) (N = 49) or high-dose (1.5 g/day) (N = 51) of carrot derived rhamnogalacturonan-I (cRG-I) for eight weeks and they were subsequently challenged with RV-16. Here, the effect of 8-week cRG-I supplementation on the gut microbiota was studied. While the overall gut microbiota composition in the population was generally unaltered by this very low dose of fibre, the relative abundance of Bifidobacterium spp. (mainly B. adolescentis and B. longum) was significantly increased by both doses of cRG-1. Moreover, daily supplementation of cRG-I led to a dose-dependent reduction in inter- and intra-individual microbiota heterogeneity, suggesting a stabilizing effect on the gut microbiota. The severity of respiratory symptoms did not directly correlate with the cRG-I-induced microbial changes, but several dominant groups of the Ruminococcaceae family and microbiota richness were positively associated with a reduced and hence desired post-infection response. Thus, the present results on the modulation of the gut microbiota composition support the previously demonstrated immunomodulatory and protective effect of cRG-I during a common cold infection.


Assuntos
Suplementos Nutricionais , Microbioma Gastrointestinal , Voluntários Saudáveis , Pectinas , Humanos , Pectinas/administração & dosagem , Pectinas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Adulto , Método Duplo-Cego , Feminino , Adulto Jovem , Rhinovirus/efeitos dos fármacos , Pessoa de Meia-Idade , Fezes/microbiologia , Bifidobacterium/efeitos dos fármacos
14.
Microbiol Spectr ; 12(6): e0413523, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38687061

RESUMO

Perinatal and early-life factors reported to affect risk of allergic diseases may be mediated by changes in the gut microbiota. Here, we explored the associations between the infant gut microbiota and allergic morbidity in childhood until 13 years of age in a subgroup of the FLORA probiotic intervention cohort. A mixture of four probiotic strains with galacto-oligosaccharides was administrated to the mothers from the 36th week of the pregnancy and later to their infants until 6 months of age. The infants were monitored for the manifestations of atopic eczema, food allergy, allergic rhinitis, and asthma by a pediatrician at 2 and 5 years of age; the allergic status was subsequently verified by a questionnaire at 10 and 13 years of age. The fecal microbiota at 3 months was profiled by 16S rRNA amplicon sequencing targeting the V3-V4 region, with and without adjusting for potentially important early-life factors. Overall, the positive diagnosis for allergic rhinitis between 2 and 13 years was associated with microbiota composition both in non-adjusted and adjusted models. This association was more pronounced in children born to one parent with confirmed atopic diseases compared to those who had two atopic parents and was characterized by a lower relative abundance of Bifidobacterium and Escherichia/Shigella spp. and a higher proportion of Bacteroides. While the probiotic and galacto-oligosaccharides intervention in the entire cohort was previously shown to reduce the prevalence of eczema to a certain extent, no associations were found between the 3-month gut microbiota and childhood eczema in the studied sub-cohort.IMPORTANCEAllergic diseases have increased in prevalence during the past decades globally. Although probiotics have been considered a promising strategy for preventing certain allergy related symptoms, studies connecting the infant gut microbiota and later life allergic morbidity in various populations remain limited. The present study supports an association between the infant microbiota and allergic morbidity after first years of life, which has been rarely examined.CLINICAL TRIALSRegistered at ClinicalTrials.gov (NCT00298337).


Assuntos
Fezes , Microbioma Gastrointestinal , Probióticos , Rinite Alérgica , Humanos , Probióticos/administração & dosagem , Rinite Alérgica/microbiologia , Feminino , Finlândia/epidemiologia , Adolescente , Pré-Escolar , Masculino , Lactente , Criança , Seguimentos , Fezes/microbiologia , RNA Ribossômico 16S/genética , Gravidez , Recém-Nascido , Estudos de Coortes , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação
15.
Gut Pathog ; 16(1): 20, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38581020

RESUMO

BACKGROUND: Intestinal botulism is primarily reported in small babies as a condition known as infant botulism. The condition results from the ingestion of environmental or foodborne spores of botulinum neurotoxin (BoNT) producing Clostridia, usually Clostridium botulinum, and subsequent spore germination into active botulinum neurotoxinogenic cultures in the gut. It is generally considered that small babies are susceptible to C. botulinum colonization because of their immature gut microbiota. Yet, it is poorly understood which host factors contribute to the clinical outcome of intestinal botulism. We previously reported a case of infant botulism where the infant recovered clinically in six weeks but continued to secrete C. botulinum cells and/or BoNT in the feces for seven months. CASE PRESENTATION: To further understand the microbial ecology behind this exceptionally long-lasting botulinum neurotoxinogenic colonization, we characterized the infant fecal microbiota using 16S rRNA gene amplicon sequencing over the course of disease and recovery. C. botulinum could be detected in the infant fecal samples at low levels through the acute phase of the disease and three months after recovery. Overall, we observed a temporal delay in the maturation of the infant fecal microbiota associated with a persistently high-level bifidobacterial population and a low level of Lachnospiraceae, Bacteroidaceae and Ruminococcaceae compared to healthy infants over time. CONCLUSION: This study brings novel insights into the infant fecal composition associated with intestinal botulism and provides a basis for a more systematic analysis of the gut microbiota of infants diagnosed with botulism. A better understanding of the gut microbial ecology associated with infant botulism may support the development of prophylactic strategies against this life-threatening disease in small babies.

16.
Biomed J ; : 100754, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38901796

RESUMO

BACKGROUND: The incidence of autoimmune diseases is increasing in developed countries, possibly due to the modern Western diet and lifestyle. We showed earlier that polysaccharides derived from the medicinal fungus Hirsutella sinensis produced anti-inflammatory, anti-diabetic and anti-obesity effects by modulating the gut microbiota and increasing the abundance of the commensal Parabacteroides goldsteinii in mice fed with a high-fat diet. METHODS: We examined the effects of the prebiotics, H. sinensis polysaccharides, and probiotic, P. goldsteinii, in a mouse model of imiquimod-induced systemic lupus erythematosus. RESULTS: The fungal polysaccharides and P. goldsteinii reduced markers of lupus severity, including the increase of spleen weight, proteinuria, and serum levels of anti-DNA auto-antibodies and signal transducer and activator of transcription 4 (STAT4). Moreover, the polysaccharides and P. goldsteinii improved markers of kidney and liver functions such as creatinine, blood urea nitrogen, glomerulus damage and fibrosis, and serum liver enzymes. However, the prebiotics and probiotics did not influence gut microbiota composition, colonic histology, or expression of tight junction proteins in colon tissues. CONCLUSIONS: Our results indicate that H. sinensis polysaccharides and the probiotic P. goldsteinii can reduce lupus markers in imiquimod-treated mice. These prebiotics and probiotics may therefore be added to other interventions conducive of a healthy lifestyle in order to counter autoimmune diseases.

17.
J Pathol ; 228(2): 158-69, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22247069

RESUMO

Hepatoma-derived growth factor (HDGF) participates in tumourigenesis but its role in breast cancer is unclear. We set out to elucidate the expression profile and function of HDGF during breast carcinogenesis. Immunoblot and immunohistochemical studies revealed elevated HDGF expression in human breast cancer cell lines and tissues. Nuclear HDGF labelling index was positively correlated with tumour grade, stage and proliferation index, but negatively correlated with survival rate in breast cancer patients. HDGF over-expression was associated with lymph node metastasis and represented an independent prognostic factor for tumour recurrence. Gene transfer studies were performed to elucidate the influence of cellular HDGF level on the malignant behaviour and epithelial-mesenchymal transition (EMT) of breast cancer cells. Adenovirus-mediated HDGF over-expression stimulated the invasiveness and colony formation of MCF-7 cells. Moreover, HDGF over-expression promoted breast cancer cell EMT by E-cadherin down-regulation and vimentin up-regulation. Conversely, HDGF knockdown by RNA interference in MDA-MB-231 cells attenuated the malignant behaviour and elicited EMT reversal by enhancing E-cadherin expression while depleting vimentin expression. Because HDGF is a secreted protein, we evaluated the cellular function of recombinant HDGF and found that exogenously supplied HDGF enhanced the invasiveness of breast cancer cells by down-regulating E-cadherin and up-regulating vimentin at transcriptional and translational levels. In contrast, blockade of HDGF secretion with an HDGF antibody inhibited the malignant behaviours and EMT. Finally, exogenous HDGF partially reversed benzyl isothiocyanate (BITC)-induced EMT suppression. HDGF over-expression may exert a prognostic role for tumour metastasis and recurrence in breast cancer by modulating EMT. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias da Mama/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Adulto , Anticorpos Bloqueadores/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Técnicas de Transferência de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Antígeno Ki-67/metabolismo , Linfonodos/patologia , Metástase Linfática , Mastectomia , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Invasividade Neoplásica/fisiopatologia , Recidiva Local de Neoplasia , Prognóstico , Proteínas Recombinantes
18.
Adv Food Nutr Res ; 106: 241-274, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37722774

RESUMO

Against the backdrop of the global protein transition needed to remain within planetary boundaries, there is an influx of plant-based meat alternatives that seek to approximate the texture, flavor and/or nutrient profiles of conventional animal meat. These novel plant-based meat alternatives, enabled by advances in food technology, can be fundamentally different from the whole-plant foods from which they are derived. One of the reasons is the necessity to use food additives on various occasions, since consumers' acceptance of plant-based meat products primarily depends on the organoleptic properties. Consequently, a high degree of heterogeneity in formulation and nutritional profiles exists both within and between product categories of plant-based meat alternatives with unknown effects on several aspects of human health. This is further complicated by the differences in digestibility and bioavailability between proteins from animal and plant sources, which have a profound impact on colonic fermentation, nutritional adequacy and potential health effects. On the other hand, emerging strategies provide opportunities to develop affordable, delicious and nutritious plant-based meat alternatives that align with consumer interests.


Assuntos
Produtos da Carne , Estado Nutricional , Animais , Humanos , Carne , Aditivos Alimentares , Nutrientes
19.
Front Endocrinol (Lausanne) ; 14: 1178155, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37305030

RESUMO

Globally, excess weight during childhood and adolescence has become a public health crisis with limited treatment options. Emerging evidence suggesting the involvement of gut microbial dysbiosis in obesity instills hope that targeting the gut microbiota could help prevent or treat obesity. In pre-clinical models and adults, prebiotic consumption has been shown to reduce adiposity partially via restoring symbiosis. However, there is a dearth of clinical research into its potential metabolic benefits in the pediatric population. Here, we provide a succinct overview of the common characteristics of the gut microbiota in childhood obesity and mechanisms of action of prebiotics conferring metabolic benefits. We then summarize available clinical trials in children with overweight or obesity investigating the effects of prebiotics on weight management. This review highlights several controversial aspects in the microbiota-dependent mechanisms by which prebiotics are thought to affect host metabolism that warrant future investigation in order to design efficacious interventions for pediatric obesity.


Assuntos
Obesidade Infantil , Criança , Adolescente , Adulto , Humanos , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Prebióticos , Sobrepeso , Adiposidade , Disbiose/epidemiologia , Disbiose/prevenção & controle
20.
Mol Nutr Food Res ; 67(20): e2300201, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37650878

RESUMO

SCOPE: While previously considered inert, recent studies suggest lignin metabolism with unknown metabolic fates is occurring in the gastrointestinal tract of several animal models. This study focuses on analyzing the potential metabolites of lignin. METHODS AND RESULTS: The diets of rats include relatively pure birch glucuronoxylan (pureGX) with residual lignin or lignin-rich GX (GXpoly) in their diet. Nuclear magnetic spectroscopy of the lignin isolated from the GXpoly-fed rats fecal sample shows high alteration in chemical structure, whereas lignin-carbohydrate complexes (LCCs) are enriched in fecal samples from the pureGX group. Moreover, the increased syringyl-to-guaiacyl (S/G) ratio suggests that lignin G-units are predominantly metabolized based on pyrolysis gas chromatography-mass spectrometry (pyr-GC/MS). The presence of small phenolic metabolites identified in urine samples of the GXpoly group, for example, ferulic and sinapic acids, their sulfate and glucuronide derivatives, and 4-sulfobenzylalcohol, suggests that the small fragmented lignin metabolites in the large intestine enter the plasma, and are further processed in the liver. Finally, the relative abundances of polyphenol-degrading Enterorhabdus and Akkermansia in the gut microbiota are associated with lignin metabolism. CONCLUSION: These findings give further evidence to lignin metabolism in the gut of nonruminants and provide insight to the potential microbes and metabolic routes.


Assuntos
Betula , Lignina , Ratos , Animais , Lignina/química , Lignina/metabolismo , Betula/metabolismo , Fibras na Dieta , Xilanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA