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1.
Nutrients ; 14(11)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35684106

RESUMO

Cancer-associated cachexia (CAC) is the nutrition-independent loss of lean muscle and adipose tissues, and results in reduced chemotherapy effectiveness and increased mortality. Preventing adipose loss is considered a key target in the early stages of cachexia. Lipolysis is considered the central driver of adipose loss in CAC. We recently found that piceatannol, but not its analogue resveratrol, exhibits an inhibitory effect on lipolysis. The objective of this study was to investigate the role of piceatannol in cancer-associated lipolysis and cachexia-induced weight loss. Cancer cell-induced lipolysis in adipocytes was stimulated using cancer-conditioned media (CCM) or co-culture with human pancreatic cancer cells and the cachexia-associated cytokines TNF-α and interleukin-6 in 3T3-L1 adipocytes. C26 colon carcinoma-bearing mice were modeled using CAC in vivo. Piceatannol reduced cancer-associated lipolysis by at least 50% in both CCM and cytokine-induced lipolysis in vitro. Further gene and protein analysis confirmed that piceatannol modulated the stability of lipolytic proteins. Moreover, piceatannol protected tumor-bearing mice against weight-loss in early stages of CAC largely through preserving adipose tissue, with no effect on survival. This study demonstrates the use of a dietary compound to preserve adipose in models of early stage CAC and provides groundwork for further investigation of piceatannol or piceatannol-rich foods as alternative medicine in the preservation of body fat mass and future CAC therapy.


Assuntos
Neoplasias do Colo , Neoplasias , Tecido Adiposo/metabolismo , Animais , Caquexia/tratamento farmacológico , Caquexia/etiologia , Caquexia/metabolismo , Neoplasias do Colo/metabolismo , Meios de Cultivo Condicionados , Citocinas/metabolismo , Lipólise , Camundongos , Neoplasias/metabolismo , Polifenóis/farmacologia , Estilbenos , Redução de Peso
2.
Ecotoxicol Environ Saf ; 232: 113244, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35093817

RESUMO

Atrazine (ATZ) is a widely used herbicide worldwide and is a long-suspected endocrine-disrupting chemical. However, most endocrine-disrupting toxicity studies on ATZ have been based on animal models and those investigating inner mechanisms have only focused on a few genes. Therefore, the possible link between ATZ and endocrine-disrupting toxicity is still unclear. In this study, multi-omics and molecular biology techniques were used to elucidate the possible molecular mechanisms underlying the effect of ATZ exposure on MCF-7 proliferation at environmentally relevant concentrations. Our study is the first report on ATZ-induced one carbon pool by folate metabolic disorder in MCF-7 cells. A concentration of 1 µM ATZ yielded the highest cell viability and was selected for further mechanistic studies. A total of 34 significantly changed metabolites were identified based on metabolomic analysis, including vitamins, amino acids, fatty acids, and corresponding derivatives. Folate and pyridoxal have potential as biomarkers of ATZ exposure. One carbon pool by folate metabolic pathway was identified based on metabolic pathway analysis of the significantly altered pathways. Moreover, FTCD and MTHFD related to this pathway were further identified based on transcriptomic analysis and protein assays. Folate and different forms of 5,6,7,8-tetrahydrofolate, which participate in purine synthesis and associate with methyl groups (SOPC, arachidonic acid, and L-tryptophan) in one carbon pool by the folate metabolic pathway, potentially promote MCF-7 cell proliferation. These findings on the key metabolites and regulation of the related differentially expressed genes in folate metabolism will shed light on the mechanism of MCF-7 cell proliferation after ATZ exposure. Overall, this study provides new insights into the mechanistic understanding of toxicity caused by endocrine-disrupting chemicals.


Assuntos
Atrazina , Herbicidas , Animais , Atrazina/metabolismo , Atrazina/toxicidade , Biomarcadores , Herbicidas/toxicidade , Humanos , Células MCF-7 , Metabolômica , Transcriptoma
3.
Food Funct ; 12(6): 2726-2740, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33681875

RESUMO

Obesity is an increasingly concerning global health issue, which is accompanied by disruption of glucose and lipid metabolisms. The aim of this study was to uncover the potential and molecular actions of puerarin, a phytochemical, for alleviating metabolic dysfunctions of glucose and lipid metabolisms. A rat model fed a high fat and high fructose diet and a HepG2 cell model challenged with fructose combined with free fatty acid were utilized to identify the effects of puerarin on obesity-associated insulin resistance and hepatic steatosis. The molecular mechanisms underlying puerarin treatment effects were further investigated using qRT-PCR and western blotting. Results show that puerarin significantly ameliorated features of obesity in rats, including bodyweight, hyperlipidemia, hyperglycemia, glucose/insulin intolerance, insulin resistance, hepatic steatosis, and oxidative stress, which are related to the activation of AMPK and PI3K/Akt pathways in the liver. Puerarin reduced lipid accumulation and caused a reduction of the mRNA expression of lipogenic genes such as SREBP-1c, FAS, SCD-1, and HMGCR, and an increment in the phosphorylation of AMPK and ACC in HepG2 cells. Moreover, puerarin ameliorated insulin resistance by increasing GLUT4 mRNA expression and activating the PI3K/Akt pathway. Treatment with the AMPK inhibitor compound C partially abolished the beneficial effects of puerarin on lipid accumulation and insulin resistance in HepG2 cells, which indicated that the protective effects of puerarin partially depend on the AMPK pathway. The present study indicates that puerarin shows potential as a functional food therapeutic for the treatment of obesity.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Glicemia , Isoflavonas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Dieta Hiperlipídica , Fígado Gorduroso/metabolismo , Células Hep G2 , Humanos , Hiperlipidemias/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Obesidade , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
4.
Phys Chem Chem Phys ; 22(23): 13108-13117, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32490501

RESUMO

Adenosine triphosphate (ATP) biomolecules play critial roles in the biomineralization process during the formation of amorphous calcium phosphate composites (ACPC), and ACPC is an important drug carrier due to its significant advantages of biocompatibility and biodegradability. Hence, studying the behavior of ACPC nanodrug carriers is crucial to investigate the structural regulation of biomimetic minerals and calcium phosphate (CaP)-based drug delivery systems. However, it is difficult to probe these interactions using traditional characterization methods. In this paper, XANES analysis together with STXM successfully provided a method to reveal the interaction of ATP and drug molecules with individual mesoporous ACPC. We found that the adenosine and phosphate groups of ATP biomolecules coordinated with Ca2+ and played critical roles in the formation of ACPC; drug molecules with the -COOH groups were linked to Ca2+via carboxylic acid groups primarily by electrostatic interactions, and the N-containing ring structures within the drug molecules also coordinated with Ca2+.


Assuntos
Trifosfato de Adenosina/química , Fosfatos de Cálcio/química , Doxorrubicina/química , Nanocompostos/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Hemoglobinas/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Espectroscopia por Absorção de Raios X
5.
Nutrients ; 11(7)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340583

RESUMO

(1) Background: Modern dietary patterns with a high intake of fat and fructose, as well as refined carbohydrates, closely relate to lipid/glucose metabolic disorders. The main objective of this study is to provide new thoughts in designing functional food with some lipid/glucose metabolism regulating effects for obese people. (2) Methods: The alleviating abilities of γ-oryzanol, phytosterol or ferulic acid-enriched wheat flour on lipid/glucose metabolic dysfunction were evaluated in male SD rats induced by a high-fat-fructose diet. The underlying mechanisms were clarified using western blot. (3) Results: In an in vitro cell model, γ-oryzanol, phytosterol and ferulic acid regulate lipid/glucose metabolism by increasing the phosphorylation of AMPK and Akt, and PI3K expression, as well as decreasing expressions of DGAT1 and SCD. The in vivo study shows that ferulic acid and γ-oryzanol-enriched flours are beneficial for managing body weight, improving glucose metabolism, hyperlipidemia and hepatic lipid accumulation. Phytosterol-enriched flour exerted remarkable effects in regulating hyperinsulinemia, insulin resistance and hyperuricemia. Western blot analysis of proteins from liver samples reveals that these enriched flours alleviated hepatic lipid accumulation and insulin resistance through their elevation in the phosphorylation of AMPK and Akt. (4) Conclusions: Our study indicates that these enriched flours can serve as a health-promoting functional food to regulate obesity-related lipid/glucose metabolic dysfunction in rats.


Assuntos
Ração Animal , Glicemia/metabolismo , Ácidos Cumáricos/administração & dosagem , Farinha , Alimentos Fortificados , Lipídeos/sangue , Doenças Metabólicas/prevenção & controle , Obesidade/prevenção & controle , Fenilpropionatos/administração & dosagem , Fitosteróis/administração & dosagem , Triticum , Animais , Biomarcadores/sangue , Ácidos Cumáricos/metabolismo , Açúcares da Dieta , Modelos Animais de Doenças , Frutose , Células Hep G2 , Humanos , Masculino , Doenças Metabólicas/sangue , Doenças Metabólicas/etiologia , Obesidade/sangue , Obesidade/etiologia , Fenilpropionatos/metabolismo , Fitosteróis/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais
6.
Angew Chem Int Ed Engl ; 58(28): 9491-9495, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31066965

RESUMO

Improving the stability of lead halide perovskite quantum dots (QDs) in a system containing water is the key for their practical application in artificial photosynthesis. Herein, we encapsulate low-cost CH3 NH3 PbI3 (MAPbI3 ) perovskite QDs in the pores of earth-abundant Fe-porphyrin based metal organic framework (MOF) PCN-221(Fex ) by a sequential deposition route, to construct a series of composite photocatalysts of MAPbI3 @PCN-221(Fex ) (x=0-1). Protected by the MOF the composite photocatalysts exhibit much improved stability in reaction systems containing water. The close contact of QDs to the Fe catalytic site in the MOF, allows the photogenerated electrons in the QDs to transfer rapidly the Fe catalytic sites to enhance the photocatalytic activity for CO2 reduction. Using water as an electron source, MAPbI3 @PCN-221(Fe0.2 ) exhibits a record-high total yield of 1559 µmol g-1 for photocatalytic CO2 reduction to CO (34 %) and CH4 (66 %), 38 times higher than that of PCN-221(Fe0.2 ) in the absence of perovskite QDs.

7.
Sheng Li Xue Bao ; 69(1): 33-40, 2017 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-28217805

RESUMO

Senescence-associated secretory phenotype (SASP) is often a concomitant result of cell senescence, embodied by the enhanced function of secretion. The SASP factors secreted by senescent cells include cytokines, proteases and chemokines, etc, which can exert great influence on local as well as systemic environment and participate in the process of cell senescence, immunoregulation, angiogenesis, cell proliferation and tumor invasion, etc. Relative to the abundance of SASP models in human cells, the in vitro SASP model derived from mouse cells is scarce at present. Therefore, the study aimed to establish a mouse SASP model to facilitate the research in the field. With this objective, we treated the INK4a-deficient mouse NIH-3T3 cells and the wildtype mouse embryonic fibroblasts (MEF) respectively with mitomycin C (MMC), an anticarcinoma drug which could induce DNA damage. The occurring of cell senescence was evaluated by cell morphology, ß-gal staining, integration ratio of EdU and Western blot. Quantitative RT-PCR and ELISA were used to detect the expression and secretion of SASP factors, respectively. The results showed that, 8 days after the treatment of NIH-3T3 cells with MMC (1 µg/mL) for 12 h or 24 h, the cells became enlarged and the ratios of ß-gal-positive (blue-stained) cells significantly increased, up to 77.4% and 90.4%, respectively. Meanwhile, the expression of P21 protein increased and the integration ratios of EdU significantly decreased (P < 0.01). Quantitative RT-PCR detection showed that the mRNA levels of several SASP genes, including IL-6, TNF-α, IL-1α and IL-1ß increased evidently. ELISA detection further observed an enhanced secretion of IL-6 (P < 0.01). On the contrary, although wildtype MEF could also be induced into senescence by MMC treatment for 12 h or 24 h, embodied by the enlarged cell volume, increased ratios of ß-gal-positive cells (up to 71.7% and 80.2%, respectively) and enhanced expression of P21 protein, the secretion of IL-6 displayed no significant change. Our study indicated that, although MMC could induce senescence in both mouse NIH-3T3 cells and wildtype MEF, only senescent NIH-3T3 cells displayed the canonical SASP phenomena. Current study suggested that senescent NIH-3T3 cells might be an appropriate in vitro SASP model of mouse cells.


Assuntos
Senescência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Mitomicina/farmacologia , Animais , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Citocinas/genética , Citocinas/metabolismo , Dano ao DNA , Interleucina-6/metabolismo , Camundongos , Células NIH 3T3 , Fenótipo
8.
Singapore Med J ; 57(6): 329-33, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27353611

RESUMO

INTRODUCTION: This study aimed to describe the knowledge, attitudes and practices of young women regarding human papillomavirus (HPV) vaccination. METHODS: We conducted a descriptive, cross-sectional, questionnaire-based study among female students at a tertiary institute in Singapore. RESULTS: A total of 255 questionnaires were completed and formed the basis of the analysis. 244 (95.7%) of the total participants were of the age group 15-22 years. 252 (98.8%) participants were unmarried and 240 (94.1%) had never had sexual intercourse. Only 25 (9.8%) women had received vaccination. Among the unvaccinated participants, 96 (41.7%) had no intention to receive HPV vaccination and 62 of them cited lack of information as a major barrier to HPV vaccination. Knowledge of cervical cancer and HPV vaccination was also assessed and graded via a point system, with a maximum score of 14. Knowledge was found to be low, with a median score of 7. There was a significant association between HPV vaccination uptake and the source from which they first heard about the vaccine (p = 0.007). Vaccinated respondents tended to first hear about it from their relatives and friends, as compared to unvaccinated respondents (60.0% vs. 27.0%). CONCLUSION: There is poor uptake of HPV vaccination amongst Singapore's susceptible youth as well as poor knowledge of cervical cancer and HPV vaccination. Public health education regarding cervical cancer and HPV vaccination is still needed and has to be targeted at not only respondents, but also their family and friends.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Neoplasias do Colo do Útero/prevenção & controle , Adolescente , Adulto , Estudos Transversais , Feminino , Educação em Saúde , Humanos , Singapura , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
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