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1.
Fitoterapia ; 173: 105815, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38168569

RESUMO

Anti-inflammatory bioassay-guided compound isolation from the exocarp of the Australian rainforest tree Endiandra insignis (family Lauraceae) has led to the discovery and structural elucidation of unusual α, ß-unsaturated twenty-four carbon fatty acids and their positional isomers, insignoic acids A - E (1a - 5c). The stereochemistry and position of the double bond within the aliphatic chain were independently determined via NMR spectroscopy and Ozone-Induced Dissociation (OzID) Mass Spectrometry, respectively. Compounds (1a - 5c) displayed good to moderate anti-inflammatory activity in the range of 8-84 µM. The low therapeutic index observed when assessing the cell viability in the RAW macrophage cell lines, prompted us to investigate the anticancer potential of these unusual fatty acids. The anti-cancer activity was assessed in A-431 carinoma cell lines and MM649 melanoma cell lines. Insignoic acid C (3a-f) exhibited the highest level of potency with an IC50 value of 5-7 µM against both the cell lines. The insignoic acids are the first of their kind known for incorporating an alpha-beta unsaturated system flanked next to a keto group with an additional level of oxygenation at C-6 in a 24­carbon fatty acid backbone.


Assuntos
Lauraceae , Árvores , Estrutura Molecular , Floresta Úmida , Austrália , Ácidos Graxos Insaturados , Ácidos Graxos , Anti-Inflamatórios , Carbono
2.
Biometals ; 32(6): 861-873, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31583500

RESUMO

The intracellular zinc profiles of breast and prostate cancer cells are diametrically opposed, with hyper-accumulation of zinc in breast cancer, and low level in prostate cancer. This phenomenon is poorly understood. This study employs two breast and two prostate cancer cell lines to investigate the role of protein kinase CK2 in regulating zinc homeostasis. CK2 was targeted by its specific inhibitors 4,5,6,7-tetrabromobenzotriazole (TBB) and CX-4945, and by the specific siRNA against each of the three CK2 genes. The effect of zinc exposure after the above CK2 manipulation was observed by MTT [3-(4,5-dimethyliazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] cell viability assay and confocal microscopy for intracellular zinc level. The results demonstrate that CK2 is involved in regulating zinc homeostasis in breast and prostate cancer cells as both TBB and CX-4945 substantially decreased cell viability upon zinc exposure. siRNA-mediated knockdown of the three CK2 subunits (α, α' and ß) revealed their discrete roles in regulating zinc homeostasis in breast and prostate cancer cells. Knockdown of CK2α' decreased the intracellular zinc level of breast cancer cells and in turn increased the cell viability while the opposite findings were obtained for the prostate cancer cells. Knockdown of CK2ß expression substantially increased the zinc level in breast cancer cell lines whilst decreased the zinc level in prostate cancer cells. Taken together, this study shows that CK2 is involved in zinc homeostasis of breast and prostate cancer cells and opens a new avenue for research on these cancers.


Assuntos
Antineoplásicos/metabolismo , Neoplasias da Mama/metabolismo , Caseína Quinase II/metabolismo , Homeostase , Neoplasias da Próstata/metabolismo , Sulfato de Zinco/metabolismo , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Caseína Quinase II/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Homeostase/efeitos dos fármacos , Humanos , Células MCF-7 , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Sulfato de Zinco/farmacologia
3.
Behav Brain Res ; 364: 328-333, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-30807810

RESUMO

Hedonic intake of strongly rewarding foods is independent from biological needs and, thus, a common cause of obesity. The effect of potato chips on energy intake in a snacking model could be explained by their fat/carbohydrate content (FCHc). The present study investigated if the FCHc shapes energy intake patterns and reward processing of satiated rodents. Modulation of energy intake patterns was studied in an established snacking model offering FCHc rich food for 3 × 10 min/day to satiated rats. Reward processing was analyzed by a previously established conditioned place preference tests in satiated mice. The limited access to FCHc rich food led to higher daily energy intake compared to days without access (110 ± 10 vs. 96 ± 5 kcal/day) indicating that fat/carbohydrate intake was not fully compensated by reducing standard chow intake during the rest of the day. Furthermore, fat/carbohydrate snacking led to binge eating episodes with up to 55% of the daily energy intake consumed during limited access. Forced withdrawal from fat/carbohydrate snacking opportunities for six weeks increased the total daily energy intake and the relative amount of energy consumed by FCHc after reintroducing fat/carbohydrate snacking. Snack food and fat/carbohydrate food were powerful food reinforcers in satiated mice in contrast to standard chow. Altogether, these data suggest that the FCHc of snack food has strong reinforcing properties, which are probably responsible for the significant modulation of the amount and pattern of food intake in ad libitum fed animals.


Assuntos
Carboidratos da Dieta/metabolismo , Gorduras na Dieta/metabolismo , Comportamento Alimentar/psicologia , Animais , Peso Corporal , Bulimia , Metabolismo dos Carboidratos , Carboidratos , Carboidratos da Dieta/efeitos adversos , Gorduras na Dieta/efeitos adversos , Ingestão de Alimentos , Ingestão de Energia , Gorduras/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade , Ratos , Ratos Wistar , Reforço Psicológico , Recompensa , Lanches
4.
J Clin Endocrinol Metab ; 103(11): 4224-4231, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30137355

RESUMO

Background: Diabetes mellitus is associated with increased fracture risk despite preservation of bone density and reduced bone turnover. Aims: We tested the hypothesis that circulating advanced glycation end products (AGEs) and endogenous secretory receptor for AGEs (esRAGE) differentially modulate bone turnover and predict fracture risk in older men. Participants: A total of 3384 community-dwelling men aged 70 to 89 years. Methods: Collagen type I C-terminal cross-linked telopeptide, N-terminal propeptide of type I collagen (P1NP), and total osteocalcin (TOC) were assayed using immunoassay and undercarboxylated osteocalcin (ucOC) following hydroxyapatite binding. Plasma N-carboxymethyllysine (CML) and esRAGE were assayed using immunoassay. Methylglyoxal and glyoxal were assayed using mass spectrometry. Incident hip fractures were ascertained. Results: Median age was 76.3 years (interquartile range, 74.2 to 79.1 years). Plasma CML was measured in 3011 men, methylglyoxal and glyoxal in 766 men, and esRAGE in 748 men. Plasma CML, methylglyoxal, glyoxal, and esRAGE were similar in men without and with diabetes (all P > 0.05). CML was positively associated with fasting glucose (r = 0.06, P < 0.001), and esRAGE was inversely associated (r = -0.08, P = 0.045). esRAGE was positively associated with bone formation (P1NP, r = 0.17, P < 0.001; ucOC, r = 0.11, P = 0.008; TOC, r = 0.16, P < 0.001). Incident hip fractures occurred in 106 men during follow-up. Men with CML in the third quartile of values had reduced incidence of hip fracture compared with men in the lowest quartile (hazard ratio, 0.49; 95% CI, 0.24 to 0.99; P = 0.045). Conclusions: Glycemia associates positively with CML and reciprocally with esRAGE in older men. Circulating esRAGE modulates bone turnover in older men, whereas CML predicts incidence of hip fracture.


Assuntos
Remodelação Óssea/fisiologia , Produtos Finais de Glicação Avançada/sangue , Fraturas do Quadril/epidemiologia , Receptor para Produtos Finais de Glicação Avançada/sangue , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biomarcadores/metabolismo , Glicemia/análise , Glicemia/metabolismo , Densidade Óssea/fisiologia , Diabetes Mellitus/sangue , Diabetes Mellitus/metabolismo , Seguimentos , Produtos Finais de Glicação Avançada/metabolismo , Fraturas do Quadril/sangue , Fraturas do Quadril/diagnóstico , Humanos , Incidência , Lisina/análogos & derivados , Lisina/sangue , Masculino , Valor Preditivo dos Testes , Prognóstico , Aldeído Pirúvico/sangue , Aldeído Pirúvico/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Fatores de Risco
5.
J Mol Neurosci ; 61(3): 289-304, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27864661

RESUMO

Alzheimer's disease (AD) is considered as one of the most prevalent neurodegenerative disorders characterized by progressive loss of mental function and ability to learn. AD is a multifactorial disorder. Various hypotheses are suggested for the pathophysiology of AD including "Aß hypothesis," "tau hypothesis," and "cholinergic hypothesis." Recently, it has been demonstrated that neuroinflammation is involved in the pathogenesis of AD. Neuroinflammation causes synaptic dysfunction and neuronal death within the brain. Excessive production of pro-inflammatory mediators induces Aß peptide production/accumulation and hyperphosphorylated tau generating inflammatory molecules and cytokines. These inflammatory molecules disrupt blood-brain barrier integrity and increase the production of Aß42 oligomers. Retinoids and carotenoids are potent antioxidants and anti-inflammatory agents having neuroprotective properties. They are able to prevent disease progression through several mechanisms such as suppression of Aß peptide production/accumulation, oxidative stress, and pro-inflammatory mediator's secretion as well as improvement of cognitive performance. These observations, therefore, confirm the neuroprotective role of retinoids and carotenoids through multiple pathways. Therefore, the administration of these nutrients is considered as a promising approach to the prevention and/or treatment of AD in the future. The aim of this review is to present existing evidences regarding the beneficial effects of retinoids and carotenoids on AD's risk and outcomes, seeking the mechanism of their action.


Assuntos
Doença de Alzheimer/metabolismo , Mediadores da Inflamação/metabolismo , Retinoides/metabolismo , Doença de Alzheimer/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Humanos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Retinoides/farmacologia , Retinoides/uso terapêutico
6.
Microsc Microanal ; 17(6): 911-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22067706

RESUMO

The detection of line-like features in images finds many applications in microanalysis. Actin fibers, microtubules, neurites, pilis, DNA, and other biological structures all come up as tenuous curved lines in microscopy images. A reliable tracing method that preserves the integrity and details of these structures is particularly important for quantitative analyses. We have developed a new image transform called the "Coalescing Shortest Path Image Transform" with very encouraging properties. Our scheme efficiently combines information from an extensive collection of shortest paths in the image to delineate even very weak linear features.


Assuntos
Algoritmos , Rastreamento de Células/métodos , Aumento da Imagem/métodos , Imageamento Tridimensional/métodos , Microscopia Confocal/métodos , Membrana Celular/ultraestrutura , Fluorescência , Neuritos/ultraestrutura
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