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1.
Life Sci ; 248: 117474, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32112869

RESUMO

BACKGROUND/OBJECTIVES: Nicotinamide N-methyltransferase (NNMT) is a novel regulator of energy homeostasis in adipocytes. NNMT expression in adipose tissue is increased in obesity and diabetes. Knockdown of NNMT prevents mice from developing diet-induced obesity, which is closely linked to insulin resistance. An early sign of systemic insulin resistance is reduced expression of glucose transporter 4 (GLUT4) selectively in adipose tissue. Adipose tissue-specific knockout and overexpression of GLUT4 cause reciprocal changes in NNMT expression. The aim of the current study was to elucidate the mechanism that regulates NNMT expression in adipocytes. METHODS: 3T3-L1 adipocytes were cultured in media with varying glucose concentrations or activators and inhibitors of intracellular pathways. NNMT mRNA and protein levels were measured with quantitative polymerase chain reaction and Western blotting. RESULTS: Glucose deprivation of 3T3-L1 adipocytes induced a 2-fold increase in NNMT mRNA and protein expression. This effect was mimicked by inhibition of glucose transport with phloretin, and by inhibition of glycolysis with the phosphoglucose isomerase inhibitor 2-deoxyglucose. Conversely, inhibition of the pentose phosphate pathway did not affect NNMT expression. Pharmacological activation of the cellular energy sensor AMP-activated protein kinase (AMPK) and inhibition of the mammalian target of rapamycin (mTOR) pathway caused an increase in NNMT levels that was similar to the effect of glucose deprivation. Activation of mTOR with MHY1485 prevented the effect of glucose deprivation on NNMT expression. Furthermore, upregulation of NNMT levels depended on functional autophagy and protein translation. CONCLUSION: Glucose availability regulates NNMT expression via an mTOR-dependent mechanism.


Assuntos
Adipócitos/efeitos dos fármacos , Transportador de Glucose Tipo 4/genética , Glucose/farmacologia , Nicotinamida N-Metiltransferase/genética , Serina-Treonina Quinases TOR/genética , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Autofagia/efeitos dos fármacos , Autofagia/genética , Transporte Biológico/efeitos dos fármacos , Diferenciação Celular , Desoxiglucose/farmacologia , Metabolismo Energético/genética , Regulação da Expressão Gênica , Glucose/metabolismo , Transportador de Glucose Tipo 4/antagonistas & inibidores , Transportador de Glucose Tipo 4/metabolismo , Glucose-6-Fosfato Isomerase/antagonistas & inibidores , Glucose-6-Fosfato Isomerase/genética , Glucose-6-Fosfato Isomerase/metabolismo , Homeostase/genética , Camundongos , Morfolinas/farmacologia , Nicotinamida N-Metiltransferase/antagonistas & inibidores , Nicotinamida N-Metiltransferase/metabolismo , Via de Pentose Fosfato/efeitos dos fármacos , Via de Pentose Fosfato/genética , Floretina/farmacologia , Biossíntese de Proteínas , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Triazinas/farmacologia
2.
J Microbiol Biotechnol ; 30(3): 333-340, 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-31893612

RESUMO

Macrophages are the cells of the first-line defense system, which protect the body from foreign invaders such as bacteria. However, Gram-negative bacteria have always been the major challenge for macrophages due to the presence of lipopolysaccharides on their outer cell membrane. In the present study, we evaluated the effect of phloretin, a flavonoid commonly found in apple, on the protection of macrophages from Escherichia coli infection. RAW 264.7 cells infected with standard E. coli, or virulent E. coli K1 strain were treated with phloretin in a dose-dependent manner to examine its efficacy in protection of macrophages. Our results revealed that phloretin treatment reduced the production of nitric oxide (NO) and generation of reactive oxygen species along with reducing the secretion of proinflammatory cytokines induced by the E. coli and E. coli K1 strains in a concentration-dependent manner. Additionally, treatment of phloretin downregulated the expression of E. coli-induced major inflammatory markers i.e. cyclooxygenase-2 (COX-2) and hemeoxygenase-1 (HO-1), in a concentration dependent manner. Moreover, the TLR4-mediated NF-κB pathway was activated in E. coli-infected macrophages but was potentially downregulated by phloretin at the transcriptional and translational levels. Collectively, our data suggest that phloretin treatment protects macrophages from infection of virulent E. coli K1 strain by downregulating the TLR4-mediated signaling pathway and inhibiting NO and cytokine production, eventually protecting macrophages from E. coli-induced inflammation.


Assuntos
Escherichia coli , Macrófagos/efeitos dos fármacos , Floretina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Inflamação , Macrófagos/metabolismo , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/biossíntese , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo
3.
Am J Clin Nutr ; 111(2): 307-318, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31840162

RESUMO

BACKGROUND: Apples are rich in bioactive polyphenols and fiber. Evidence suggests that consumption of apples or their bioactive components is associated with beneficial effects on lipid metabolism and other markers of cardiovascular disease (CVD). However, adequately powered randomized controlled trials are necessary to confirm these data and explore the mechanisms. OBJECTIVE: We aimed to determine the effects of apple consumption on circulating lipids, vascular function, and other CVD risk markers. METHODS: The trial was a randomized, controlled, crossover, intervention study. Healthy mildly hypercholesterolemic volunteers (23 women, 17 men), with a mean ± SD BMI 25.3 ± 3.7 kg/m2 and age 51 ± 11 y, consumed 2 apples/d [Renetta Canada, rich in proanthocyanidins (PAs)] or a sugar- and energy-matched apple control beverage (CB) for 8 wk each, separated by a 4-wk washout period. Fasted blood was collected before and after each treatment. Serum lipids, glucose, insulin, bile acids, and endothelial and inflammation biomarkers were measured, in addition to microvascular reactivity, using laser Doppler imaging with iontophoresis, and arterial stiffness, using pulse wave analysis. RESULTS: Whole apple (WA) consumption decreased serum total (WA: 5.89 mmol/L; CB: 6.11 mmol/L; P = 0.006) and LDL cholesterol (WA: 3.72 mmol/L; CB: 3.86 mmol/L; P = 0.031), triacylglycerol (WA: 1.17 mmol/L; CB: 1.30 mmol/L; P = 0.021), and intercellular cell adhesion molecule-1 (WA: 153.9 ng/mL; CB: 159.4 ng/mL; P = 0.028), and increased serum uric acid (WA: 341.4 µmol/L; CB: 330 µmol/L; P = 0.020) compared with the CB. The response to endothelium-dependent microvascular vasodilation was greater after the apples [WA: 853 perfusion units (PU), CB: 760 PU; P = 0.037] than after the CB. Apples had no effect on blood pressure or other CVD markers. CONCLUSIONS: These data support beneficial hypocholesterolemic and vascular effects of the daily consumption of PA-rich apples by mildly hypercholesterolemic individuals.This trial was registered at clinicaltrials.gov as NCT01988389.


Assuntos
Dieta , Frutas , Hipercolesterolemia/sangue , Malus , Adulto , Biomarcadores , Pressão Sanguínea , Colesterol/sangue , Estudos Cross-Over , Endotélio Vascular/fisiologia , Feminino , Humanos , Hipercolesterolemia/dietoterapia , Masculino , Pessoa de Meia-Idade , Valor Nutritivo , Floretina/metabolismo , Urinálise , Rigidez Vascular
4.
Biosci Biotechnol Biochem ; 84(4): 815-823, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31791197

RESUMO

We investigated whether low-dose phloretin served as daily dietary supplements could ameliorate diabetic atherosclerosis and the role of kruppel-like factor 2 (KLF2). HUVECs cultured in high glucose medium were treated with different concentrations of phloretin and KLF2 mRNA, and protein level was detected. Diabetes was induced using streptozotocin in Apoe-/- mice after which they were fed a high-cholesterol diet for 8 weeks. Diabetic mice injected with KLF2 shRNA-lentivirus or control virus were treated with 20 mg/kg phloretin. Glucose, lipid profile, aortic atheroma, and endothelial nitric oxide synthase (eNOS) expression were detected. Phloretin retained endothelial function by KLF2-eNOS activation under hyperglycemia. Low-dose phloretin helped with lipid metabolism, and blocked the acceleration of atherosclerosis in STZ-induced diabetic mice since the early stage, which was diminished by KLF2 knockdown. Low-dose phloretin exhibited athero-protective effect in diabetic Apoe-/- mice dependent on KLF2 activation. This finding makes phloretin for diabetic atherosclerosis.


Assuntos
Aterosclerose/prevenção & controle , Diabetes Mellitus Experimental/complicações , Endotélio Vascular/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Floretina/farmacologia , Animais , Aterosclerose/complicações , Aterosclerose/metabolismo , Glicemia/análise , Diabetes Mellitus Experimental/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática , Células Endoteliais da Veia Umbilical Humana , Humanos , Hiperglicemia/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase Tipo III/metabolismo , Floretina/administração & dosagem , Transdução Genética
5.
Food Chem ; 308: 125569, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31644967

RESUMO

In this study, the solubility of phloretin (PT) was enhanced via steviol glycoside (STE)-based micelle (MC) and solid dispersion (SD). Computer simulation, characterization, interaction with serum albumin (SA) and in vitro release were carried out to investigate the solubilization mechanisms and the difference in their solubilization capacities. For PT-loaded MC (STE-PT MC), PT was encapsulated into the hydrophobic core of a spherical micelle with a droplet diameter of 5 nm. For PT-loaded SD (STE-PT SD), PT was completely dispersed with the amorphous state in STE. Most of those PTs were directly dissolved in water, and few were encapsulated by STE micelles. The amorphous state combined with relatively large micelles contributed to the high solubilization capacity of STE-PT SD. In addition, PT of STE-PT SD exhibited a higher dissolution rate and more effective interaction with SA than that of STE-PT MC. No undesirable chemical interaction between PT and STE occurred.


Assuntos
Diterpenos de Caurano/química , Glucosídeos/química , Floretina/química , Interações Hidrofóbicas e Hidrofílicas , Micelas , Floretina/análise , Solubilidade , Água/química
6.
Phytomedicine ; 66: 153111, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31790902

RESUMO

BACKGROUND: Hyperuricemia (HUA) is an important risk factor for renal diseases and contributes to renal fibrosis. It has been proved that phloretin has antioxidant and anti-inflammatory properties and could inhibit uric acid (UA) uptake in vitro. However, whether phloretin has a renal protective role in vivo remains unknown. PURPOSE: This study aims to evaluate the therapeutic effect of phloretin on HUA-induced renal injury in mice and to reveal its underlying mechanism. METHODS: Mice were induced hyperuricemic by oral gavage of adenine/potassium oxonate. The effects of phloretin on renal function, fibrosis, oxidative stress, inflammation, and UA metabolism in HUA mice were evaluated. The effect of phloretin on NLRP3 pathway was analyzed in human renal tubular cell lines (HK-2). RESULTS: HUA mice showed renal dysfunction with increased renal fibrosis, inflammation and mitochondrial stress. By contrast, phloretin reduced the level of serum blood urea nitrogen (BUN), urinary albumin to creatinine ratio (UACR), tubular necrosis, extracellular matrix (ECM) deposition and interstitial fibroblasts in HUA mice. The renal infiltration of inflammatory cells, cytokines such as NOD-like receptor family pyrin domain containing 3 (NLRP3) and interleukin-1ß (IL-1ß) release, mitochondrial reactive oxygen species (ROS) and morphological lesions in HUA mice also decreased. Furthermore, phloretin partly inhibited renal glucose transporter 9 (GLUT9) and promoted urinary UA excretion in HUA mice. In vitro, phloretin suppressed the NLPR3 pathway under LPS or UA stimulation in HK-2 cells. CONCLUSIONS: Phloretin could effectively attenuate UA-induced renal injury via co-inhibiting NLRP3 and UA reabsorption, and thus it might be a potential therapy to hyperuricemia-related renal diseases.


Assuntos
Fibrose/tratamento farmacológico , Hiperuricemia/tratamento farmacológico , Inflamação/tratamento farmacológico , Nefropatias/tratamento farmacológico , Floretina/farmacologia , Ácido Úrico/metabolismo , Animais , Linhagem Celular , Citocinas/metabolismo , Humanos , Inflamassomos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Molecules ; 24(23)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766432

RESUMO

Streptococcus pyogenes is well documented as a multi-virulent and exclusively human pathogen. The LuxS-based signaling in these bacteria has a crucial role in causing several infections through pathways that are pathogenic. This study evaluated the individual and synergistic effects of citral and phloretin against S. pyogenes in relation to major virulence traits. The in vitro synergy of citral and phloretin was evaluated by the checkerboard method. The fractional inhibitory concentration (FIC) values were calculated to determine the interactions between the inhibitors. The bacteria's virulence properties were tested in the presence of the molecules, individually as well as in combination. Molecules' cytotoxicity was tested using human tonsil epithelial cells. The synergistic effects of the molecules on the expression of biofilm and quorum sensing genes were tested using quantitative real-time polymerase chain reaction (qRT-PCR). The molecules were also tested for their impact on LuxS protein by molecular docking, modeling, and free-energy calculations. When the two molecules were assessed in combination (synergistic effect, FIC Index of 0.5), a stronger growth inhibitory activity was exhibited than the individual molecules. The cell surface hydrophobicity, as well as genes involved in quorum sensing and biofilm formation, showed greater suppression when the molecules were tested in combination. The in silico findings also suggest the inhibitory potential of the two molecules against LuxS protein. The binding orientation and the binding affinity of citral and phloretin well support the notion that there is a synergistic effect of citral and phloretin. The data reveal the combination of citral and phloretin as a potent antibacterial agent to combat the virulence of S. pyogenes.


Assuntos
Monoterpenos Acíclicos/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Liases de Carbono-Enxofre/antagonistas & inibidores , Floretina/farmacologia , Infecções Estreptocócicas/tratamento farmacológico , Streptococcus pyogenes/efeitos dos fármacos , Virulência/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Células Cultivadas , Combinação de Medicamentos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Tonsila Palatina/citologia , Tonsila Palatina/efeitos dos fármacos , Conformação Proteica , Percepção de Quorum , Infecções Estreptocócicas/microbiologia
8.
Am J Physiol Gastrointest Liver Physiol ; 317(6): G839-G844, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31604028

RESUMO

Pigs are capable of nitrogen salvage via urea recycling, which involves the movement of urea in the gastrointestinal tract. Aquaporins (AQP) and urea transporter B (UT-B) are involved in urea recycling in ruminants; however, their contribution to urea flux in the intestinal tract of the pig is not known. The objective of this study was to characterize the presence and relative contribution of known urea transporters to urea flux in the growing pig. Intestinal tissue samples (duodenum, jejunum, ileum, cecum, and colon) were obtained from nine barrows (50.8 ± 0.9 kg) and analyzed for mRNA abundance of UT-B and AQP-3, -7, and -10. Immediately after tissue collection, samples from the jejunum and cecum were placed in Ussing chambers for analysis of the serosal-to-mucosal urea flux (Jsm-urea) with no inhibition or when incubated in the presence of phloretin to inhibit UT-B-mediated transport, NiCl2 to inhibit AQP-mediated transport, or both inhibitors. UT-B expression was greatest (P < 0.05) in the cecum, whereas AQP-3, -7, and -10 expression was greatest (P < 0.05) in the jejunum. The Jsm-urea was greater in the cecum than the jejunum (67.8 . 42.7 ± 5.01 µmol·cm-2·h-1; P < 0.05), confirming the capacity for urea recycling in the gut in pigs; however, flux rate was not influenced (P > 0.05) by urea transporter inhibitors. The results of this study suggest that, although known urea transporters are expressed in the gastrointestinal tract of pigs, they may not play a significant functional role in transepithelial urea transport.NEW & NOTEWORTHY We characterized the location and contribution of known urea transporters to urea flux in the pig. Aquaporins are located throughout the intestinal tract, and urea transporter B is expressed only in the cecum. Urea flux occurred in both the jejunum and cecum. Transporter inhibitors had no affect on urea flux, suggesting that their contribution to urea transport in the intestinal tract is limited. Further work is required to determine which factors contribute to urea flux in swine.


Assuntos
Aquaporinas/metabolismo , Ceco/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Floretina/farmacologia , Ureia/metabolismo , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Transporte Biológico Ativo/fisiologia , Flavonoides/farmacologia , Trato Gastrointestinal/metabolismo , Mucosa Intestinal/metabolismo , Suínos
9.
Food Funct ; 10(9): 5752-5758, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31453624

RESUMO

Phloretin, abundantly present in apples, pears and other fruits, has been found to have antioxidant, immunosuppressive and anti-inflammatory activities. It has been reported that oral administration of phloretin dose-dependently increased feed intake in mice, but the mechanism is unclear yet. The aim of this study was to investigate the effect of dietary phloretin supplementation on the feed intake in C57BL/6J mice and to identify its mechanism. Here, sixty C57BL/6J mice (28-day age) were randomly chosen for four dietary treatments and fed a basal diet or a basal diet supplemented with 0.1%, 0.2%, and 0.3% phloretin, respectively, in a 6-week trial. We showed that mice in the 0.1%, 0.2%, and 0.3% phloretin-supplemented groups had increased accumulative feed intake compared with the control group. Furthermore, dietary phloretin supplementation significantly increased the ghrelin mRNA level in the stomach and hypothalamus, and decreased the cholecystokinin (CCK) mRNA level in the duodenum in a dose-dependent manner. The mRNA levels of neuropeptide Y (NPY), agouti-related protein (AgRP), pro-opiomelanocortin and melanocortin receptors 4 (MC4R), and pro-opiomelanocortin (POMC) in the hypothalamus were altered in response to dietary phloretin supplementation. Moreover, we confirmed that dietary phloretin supplementation reduced the expressions of miR-488 and miR-103, two feed intake-related miRNAs. Our present study provides evidence that dietary phloretin supplementation could increase feed intake in mice, which might be attributed to the stimulation of the hypothalamic feeding center via ghrelin, miRNAs (miR-103 and miR-488) and feeding signal factor-related genes (NPY, AgRP, MC4R and POMC), and to the inhibition of CCK to increase gastric emptying.


Assuntos
Suplementos Nutricionais/análise , Ingestão de Alimentos/efeitos dos fármacos , Floretina/administração & dosagem , Animais , Colecistocinina/genética , Colecistocinina/metabolismo , Duodeno/efeitos dos fármacos , Duodeno/metabolismo , Expressão Gênica/efeitos dos fármacos , Grelina/metabolismo , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Receptor Tipo 4 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/metabolismo
10.
J Chromatogr Sci ; 57(8): 679-687, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31298265

RESUMO

In the present study, a systematic validated method was developed for the determination of two key dietary dihydrochalcones (DHC) viz. phloridzin (PZ) and phloretin (PT) in the leaves of Sikkim crabapple (Malus sikkimensis) using HPLC-Photo Diode Array (PDA). Chromatographic separation was optimized on a C18 column using a gradient elution of water/acetonitrile with the flow rate of 1.0 mL/min at 25°C at 280 nm. Sample preparation approach is rapid and energy efficient, and it requires no pre-concentration before analysis. Validation showed a good analytical performance in terms of specificity, linearity (r2 > 0.999), precision (% RSD < 1.08), recovery (97-100.4%) and sensitivities (limits of detection: 12.48 and 14.95 ng/mL; limit of quantification: 41.61 and 49.85 ng/mL) of PZ and PT, respectively. Developed approach was employed for targeted phytochemical analysis in the bark and fruits of M. sikkimensis. The PZ content in the bark and leaves was highest (12-13 mg/100 mg), about 90-fold higher than fruits. PT was only present in the leaves (0.57 mg/100 mg). The comparative data on PZ and PT content in various wild apple species/cultivar from different countries have also been discussed. The reliability of the validated method was established by analyzing global and expanded uncertainties in two DHC determinations in wild apple. The present method fulfills the technical requirement of ISO 17025:2017 for quality control of M. sikkimensis.


Assuntos
Chalconas/análise , Cromatografia Líquida de Alta Pressão/métodos , Malus/química , Extratos Vegetais/análise , Índia , Limite de Detecção , Floretina/análise , Florizina/análise , Folhas de Planta/química
11.
Life Sci ; 232: 116600, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251998

RESUMO

Neuroinflammation is one of the significant neuropathological conditions in Parkinson's disease (PD) which is due to microglial and astrocytes activation leads to progressive dopaminergic neuronal loss. To date, Current PD drugs offers only symptomatic relief with adverse effects and lack of ability to prevent the progression of neurodegeneration. Therefore, a better approach to develop a multi potent drug of natural origin would be beneficial in managing the disease. Therefore, the present study aimed to investigate the neuroprotective and anti-inflammatory effects of PHL by exploring its neuroprotective mechanism in 1-methyl-4-phenyl-1,2,3,6-tetrahydro pyridine (MPTP) induced PD in mice. MPTP intoxication in mice cause motor abnormalities, decreased dopamine (DA) levels, reduced tyrosine hydroxylase (TH) enzyme protein expression and inflammation which were effectively restored by PHL. Moreover gliotic specific inflammatory markers like glial fibrillary acidic protein (GFAP), ionized calcium-binding adaptor protein-1 (Iba-1), iNOS and COX-2 were found to be expressed more in MPTP intoxicated mice, Further the levels of proinflammatory cytokines like IL-ß, IL-6, and TNF-α were significantly upregulated in MPTP intoxicated mice, these deleterious responses were diminished to extend neuroprotection by PHL treatment. Our findings strongly suggest PHL as a potent therapeutic agent in treating PD.


Assuntos
Transtornos Parkinsonianos/tratamento farmacológico , Floretina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/metabolismo , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Microglia/efeitos dos fármacos , Neuroimunomodulação/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/patologia , Tirosina 3-Mono-Oxigenase/metabolismo
12.
Phytomedicine ; 62: 152964, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31153059

RESUMO

BACKGROUND: Phloretin, a dihydrochalcone flavonoid, possesses anti-inflammatory activity and inhibits the growth of various cancers. However, the flavonoid's effect on cervical cancer metastasis and angiogenesis remains unknown. PURPOSE: In this study, we provide molecular evidence associated with the antimetastatic and antiangiogenic effects of phloretin. METHODS: In this study, the anti-invasive effect of phloretin (0-60 µM) in cervical cancer cells was evaluated using the Matrigel invasion assay, gelatin zymography, cell-matrix adhesion assay, wound healing assay, and Western blotting. Antiangiogenic potential of phloretin (0-100 µM) was assessed by the Matrigel tube formation assay. The in vivo antitumor effect of phloretin (10 or 20 mg/kg) was fed by oral gavage and determined using subcutaneous inoculation and tail vein injection in immunodeficient nude mice. RESULTS: Phloretin (60 µM) showed marked suppression of invasion and migration through downregulation of matrix metalloproteinase (MMP)-2, MMP-3, and cathepsin S in human SiHa cervical cancer cells. Phloretin (60 µM) reversed the epithelial-mesenchymal transition induced by transforming growth factor-ß1 and downregulated mesenchymal markers, such as fibronectin, vimentin, and RhoA. Phloretin (100 µM) treatment significantly inhibited the aldehyde dehydrogenase 1 activity of SiHa cells, reduced the self-renewal properties and stemness signatures of CD44 and Sox-2 in sphere-forming cervical cancer-derived tumor-initiating cells, and inhibited the invasion, MMP-2 activity, and tube formation capacity of human umbilical vein endothelial cells. The ability of phloretin (20 mg/kg) to suppress lung metastasis and tumor growth in SiHa cells was evidenced by tail vein injection and subcutaneous inoculation in a tumor xenograft model. CONCLUSION: In summary, the findings indicate that phloretin inhibits the metastatic and angiogenic abilities and cancer stemness of SiHa cells, thereby suggesting that this flavonoid is a promising therapeutic agent for the treatment of human cervical cancer cells.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Pulmonares/prevenção & controle , Metaloproteinases da Matriz/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico , Floretina/administração & dosagem , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Pulmonares/secundário , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica/prevenção & controle , Metástase Neoplásica/prevenção & controle , Neoplasias do Colo do Útero/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Int J Mol Sci ; 20(10)2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31137461

RESUMO

Phloretin has pleiotropic effects, including glucose transporter (GLUT) inhibition. We previously showed that phloretin promoted adipogenesis of bone marrow stromal cell (BMSC) line ST2 independently of GLUT1 inhibition. This study investigated the effect of phloretin on osteoblastogenesis of ST2 cells and osteoblastic MC3T3-E1 cells. Treatment with 10 to 100 µM phloretin suppressed mineralization and expression of osteoblast differentiation markers, such as alkaline phosphatase (ALP), osteocalcin (OCN), type 1 collagen, runt-related transcription factor 2 (Runx2), and osterix (Osx), while increased adipogenic markers, peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), fatty acid-binding protein 4, and adiponectin. Phloretin also inhibited mineralization and decreased osteoblast differentiation markers of MC3T3-E1 cells. Phloretin suppressed phosphorylation of Akt in ST2 cells. In addition, treatment with a phosphatidylinositol 3-kinase (PI3K)/Akt inhibitor, LY294002, suppressed the mineralization and the expression of osteoblast differentiation markers other than ALP. GLUT1 silencing by siRNA did not affect mineralization, although it decreased the expression of OCN and increased the expression of ALP, Runx2, and Osx. The effects of GLUT1 silencing on osteoblast differentiation markers and mineralization were inconsistent with those of phloretin. Taken together, these findings suggest that phloretin suppressed osteoblastogenesis of ST2 and MC3T3-E1 cells by inhibiting the PI3K/Akt pathway, suggesting that the effects of phloretin may not be associated with glucose uptake inhibition.


Assuntos
Cálcio/metabolismo , Diferenciação Celular , Osteoblastos/efeitos dos fármacos , Floretina/farmacologia , Animais , Proteína Morfogenética Óssea 2/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteoblastos/citologia , Osteoblastos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
14.
Nutrients ; 11(5)2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31130634

RESUMO

Plant-derived food consumption has gained attention as potential intervention for the improvement of intestinal inflammatory diseases. Apple consumption has been shown to be effective at ameliorating intestinal inflammation symptoms. These beneficial effects have been related to (poly)phenols, including phloretin (Phlor) and its glycoside named phloridzin (Phldz). To deepen the modulatory effects of these molecules we studied: i) their influence on the synthesis of proinflammatory molecules (PGE2, IL-8, IL-6, MCP-1, and ICAM-1) in IL-1ß-treated myofibroblasts of the colon CCD-18Co cell line, and ii) the inhibitory potential of the formation of advanced glycation end products (AGEs). The results showed that Phlor (10-50 µM) decreased the synthesis of PGE2 and IL-8 and the formation of AGEs by different mechanisms. It is concluded that Phlor and Phldz, compounds found exclusively in apples, are positively associated with potential beneficial effects of apple consumption.


Assuntos
Colo/efeitos dos fármacos , Frutas/química , Inflamação/metabolismo , Malus/química , Floretina/farmacologia , Florizina/farmacologia , Extratos Vegetais/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Linhagem Celular , Colo/metabolismo , Colo/patologia , Dieta , Dinoprostona/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Inflamação/dietoterapia , Inflamação/tratamento farmacológico , Doenças Inflamatórias Intestinais/dietoterapia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-1beta , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Floretina/uso terapêutico , Florizina/uso terapêutico , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Fitoterapia , Extratos Vegetais/uso terapêutico , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Receptores CCR2/metabolismo
15.
Chem Biol Interact ; 308: 11-19, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31071336

RESUMO

The main aim of this study was to investigate the effects of phloretin loaded chitosan nanoparticles (PhCsNPs) on 7,12-dimethylbenz[a]anthracene (DMBA) induced experimental cancer in hamsters. Oral squamous cell carcinoma (OSCC) was induced in male golden Syrian hamsters by painting with 0.5% DMBA three times a week for 14 weeks. Varying concentration of PhCsNPs (5, 10, and 20 mg/kg b.wt.) was orally administered on alternative days to evaluate the optimum dose. The experiment design was terminated at the end of the 14th week. The development of OSCC was confirmed by histopathological and biochemical analysis (lipid peroxidation, antioxidant profile, and detoxification enzymes) in plasma, erythrocyte, buccal, and liver tissues. Significant increases in oxidation and lipid peroxidation were noticed in DMBA-painted hamsters. Oral administration of PhCsNPs in various doses on alternate days reversed the deleterious effects induced by DMBA. In addition, immunoblot analyses of PhCsNPs treatment enhanced the release of Bcl-2 associated X protein (Bax), cytochrome c, caspase-3, 9 and suppressed the B-cell lymphoma 2 (Bcl-2) expression, which the use of PhCsNPs for mitochondrial-mediated apoptosis. These findings suggest biofabricated PhCsNPs may act as a potent antioxidant and anti-carcinogenic in DMBA induced oral cancer in experimental animals.


Assuntos
Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Quitosana/química , Nanopartículas/química , Floretina/farmacologia , Administração Oral , Animais , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Caspase 3/metabolismo , Cricetinae , Sistema Enzimático do Citocromo P-450/metabolismo , Citocromos c/metabolismo , Regulação para Baixo/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Neoplasias Bucais/induzido quimicamente , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/patologia , Floretina/química , Floretina/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
16.
Food Chem Toxicol ; 129: 291-300, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31059746

RESUMO

Methylglyoxal (MGO), a cytotoxic factor, reacts irreversibly with the side chains of lysine, cysteine, and arginine residues in proteins to form advanced glycation end products (AGEs) which might be a major pathological factor associated with diabetic complications. Thus, it is necessary to prevent or alleviate such diseases through inhibiting the formation of AGEs or lowering these AGEs-induced cellular damages. Based on our previous work, it was known that phloretin, an apple polyphenol, can inhibit the formation of AGEs under simulated physiological conditions. In this study, we found that phloretin prevented the formation of AGEs through trapping MGO in human umbilical endothelial cells (HUVECs). The phloretin-MGO adducts were analyzed in PBS and HUVECs. Surprisingly, only 1 MGO-phloretin adduct was detected in HUVECs, which was formed within 0.5 h and metabolized eventually within 24 h. The specific phloretin-MGO adduct was synthesized and identified by MS and NMR analysis. Its anti-inflammatory effect against AGEs was further investigated together with the parent compound, phloretin, which was proved to be through RAGE/p38 MAPK/NF-κB signaling pathway. Taken together, our data indicated the positive role of phloretin-MGO adduct on phloretin's protective effects, which might offer a new insight into the action mechanism of polyphenols against AGEs-induced damages.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Produtos Finais de Glicação Avançada/metabolismo , Inflamação/metabolismo , Floretina/farmacologia , Aldeído Pirúvico/farmacologia , Sistema Livre de Células , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , NF-kappa B/metabolismo , Floretina/química , Polifenóis/farmacologia , Aldeído Pirúvico/química , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
J Agric Food Chem ; 67(16): 4513-4523, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30929431

RESUMO

The everted gut sacs and Caco-2 cell models were used to investigate the intestinal absorptive characteristics and subcellular localization of chitobiose and chitopentaose in this study. In everted gut sacs, the absorptive pattern showed no concentration-dependent manner when the concentration was lower than 10 mM. In the presence of phlorizin (100 µM) and phloretin (100 µM), the chitobiose absorption rates decreased by (4.97 ± 0.89)% and (19.2 ± 2.77)%, and they were (10.4 ± 2.43)% and (27.5 ± 1.68)% for chitopentaose. In Caco-2 cells, the concentration showed influences similar to those with the everted gut sacs results. After adding phlorizin and phloretin in the apical side, the PappAP-BL of chitobiose and chitopentaose significantly decreased. Considering the translocation, they were enriched in endoplasmic reticulum and mitochondrion. This study indicated that concentration and active transporter were capable of mediating the absorption of chitobiose and chitopentaose, and the subcellular localization of them could help to study the mechanisms of their effects.


Assuntos
Dissacarídeos/metabolismo , Mucosa Intestinal/metabolismo , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Humanos , Mucosa Intestinal/efeitos dos fármacos , Intestinos/fisiologia , Modelos Biológicos , Floretina/farmacologia , Florizina/farmacologia
18.
Molecules ; 24(7)2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30987239

RESUMO

Phloretin is a natural chalcone with antibacterial and anti-inflammatory effects. This study investigated the anti-acne activity of phloretin against Propionibacterium acnes-induced skin infection and the potential target proteins of its anti-inflammatory and antibacterial effects. Phloretin potently inhibited the growth of P. acnes and P. acnes-induced Toll-like receptor (TLR) 2-mediated inflammatory signaling in human keratinocytes. Secreted embryonic alkaline phosphatase assay confirmed that the anti-inflammatory activity of phloretin is associated with the P. acnes-stimulated TLR2-mediated NF-κB signaling pathway. Phloretin significantly decreased the level of phosphorylated c-Jun N-terminal kinase (JNK), showing a binding affinity of 1.184 × 10-5 M-1. We also found that phloretin binds with micromolar affinity to P. acnes ß-ketoacyl acyl carrier protein (ACP) synthase III (KAS III), an enzyme involved in fatty acid synthesis. Conformation-sensitive native polyacrylamide gel electrophoresis showed that phloretin reduced KAS III-mediated 3-ketoacyl ACP production by over 66%. A docking study revealed that phloretin interacts with the active sites of JNK1 and KAS III, suggesting their involvement in P. acnes-induced inflammation and their potential as targets for the antibacterial activity of phloretin. These results demonstrate that phloretin may be useful in the prevention or treatment of P. acnes infection.


Assuntos
Antibacterianos/farmacologia , Infecções por Bactérias Gram-Positivas/metabolismo , Infecções por Bactérias Gram-Positivas/microbiologia , Floretina/farmacologia , Propionibacterium acnes/efeitos dos fármacos , Dermatopatias Bacterianas/metabolismo , Dermatopatias Bacterianas/microbiologia , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/antagonistas & inibidores , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/química , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/metabolismo , Antibacterianos/química , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocinas/biossíntese , Relação Dose-Resposta a Droga , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Floretina/química , Propionibacterium acnes/enzimologia , Propionibacterium acnes/imunologia , Ligação Proteica , Dermatopatias Bacterianas/tratamento farmacológico , Relação Estrutura-Atividade , Receptor 2 Toll-Like/metabolismo
19.
Int J Antimicrob Agents ; 54(1): 80-84, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30930299

RESUMO

Zika virus (ZIKV) is a re-emerging Flavivirus that has been linked to microcephaly and other neurological pathologies. In this study, phloretin, a glucose transporter inhibitor naturally derived from plants, was used to investigate the glucose dependence of ZIKV replication in host cells. The results showed that phloretin significantly decreased infectious titres of two ZIKV strains, namely MR766 (African genotype) and PRVABC59 (Puerto Rico genotype). The 50% effective concentration (EC50) of phloretin against MR766 and PRVABC59 was 22.85 µM and 9.31 µM, respectively. Further analyses demonstrated that decreased viral production was due to host-targeted inhibition, including decreased apoptotic caspase-3 and -7 activities and reduced phosphorylation of Akt/mTOR pathways. In addition, upon disruption of cellular glucose availability within host cells using 2-deoxy-d-glucose, ZIKV propagation was inhibited. Collectively, we demonstrate phloretin inhibition of ZIKV propagation and provide evidence of glucose utilization pathways as being important for ZIKV propagation. The activity of phloretin and its role in inhibiting glucose uptake could provide a useful foundation for the development of ZIKV antivirals.


Assuntos
Antivirais/farmacologia , Metabolismo dos Carboidratos/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Floretina/farmacologia , Replicação Viral/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Animais , Chlorocebus aethiops , Células Vero , Carga Viral , Zika virus/crescimento & desenvolvimento
20.
Mini Rev Med Chem ; 19(13): 1060-1067, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30864525

RESUMO

Over the past two decades, many researchers have concluded that a diet rich in polyphenolic compounds plays an important therapeutic role in reducing the risk of cancer, cardiovascular disease, inflammation, diabetes, and other degenerative diseases. Polyphenolic compounds have been reported to be involved in neutralization of reactive oxygen species and charged radicals, and have anticarcinogenic effects, hepatoprotective effects, low-glycaemic response, and other benefits. The benefits of fruits and vegetables may be partly attributable to polyphenolic compounds, which have antioxidant and free radical scavenging properties. Fruits such as apples contain a variety of phytochemicals, including (+)-catechin and (-)-epicatechin, phlorizin, phloretin quercetin, cyanidin-3-Ogalactoside, chlorogenic acid, and p-coumaric acid, all of which are strong antioxidants. Phloretin, a natural phenolic compound, is a dihydrochalcone, which is present in the apple. It exhibits a wide variety of activities such as antioxidative, anti-inflammatory, anti-microbial, anti-allergic, anticarcinogenic, anti-thrombotic, and hepatoprotective, besides being involved in the activation of apoptotic associated gene expression and signal transduction in molecular pathways. Despite a multitude of clinical studies, new efforts are needed in clinical research to determine the complete therapeutic potential of phloretin.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Hipoglicemiantes/farmacologia , Floretina/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Antioxidantes/química , Antioxidantes/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Doenças Cardiovasculares/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Inflamação/tratamento farmacológico , Neoplasias/tratamento farmacológico , Floretina/química , Floretina/uso terapêutico
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