Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Mar Drugs ; 22(2)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38393062

RESUMO

The present study aims to explore the probable anti-adipogenesis effect of Dictyopteris divaricata (D. divaricata) in 3T3-L1 preadipocytes by regulating heme oxygenase-1 (HO-1). The extract of D. divaricata retarded lipid accretion and decreased triglyceride (TG) content in 3T3-L1 adipocytes but increased free glycerol levels. Treatment with the extract inhibited lipogenesis by inhibiting protein expressions of fatty acid synthase (FAS) and lipoprotein lipase (LPL), whereas lipolysis increased by activating phosphorylation of hormone-sensitive lipase (p-HSL) and AMP-activated protein kinase (p-AMPK). The extract inhibited adipocyte differentiation of 3T3-L1 preadipocytes through down-regulating adipogenic transcription factors, including peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein 1 (SREBP1). This is attributed to the triggering of Wnt/ß-catenin signaling. In addition, this study found that treatment with the extract activated HO-1 expression. Pharmacological approaches revealed that treatment with Zinc Protoporphyrin (ZnPP), an HO-1 inhibitor, resulted in an increase in lipid accumulation and a decrease in free glycerol levels. Finally, three adipogenic transcription factors, such as PPARγ, C/EBPα, and SREBP1, restored their expression in the presence of ZnPP. Analysis of chemical constituents revealed that the extract of D. divaricata is rich in 1,4-benzenediol, 7-tetradecenal, fucosterol, and n-hexadecanoic acid, which are known to have multiple pharmacological properties.


Assuntos
Adipogenia , Phaeophyceae , Animais , Camundongos , Lipólise , Células 3T3-L1 , Heme Oxigenase-1/metabolismo , PPAR gama/metabolismo , Glicerol/farmacologia , Glicerol/metabolismo , Diferenciação Celular , Adipócitos , Proteína alfa Estimuladora de Ligação a CCAAT , Fatores de Transcrição/metabolismo , Lipídeos/farmacologia
2.
Int J Mol Sci ; 24(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37446242

RESUMO

Angiotensin I-converting enzyme (ACE) is an important blood pressure regulator. In this study, we aimed to investigate the ACE-inhibitory effects of meroterpenoids isolated from the brown alga, Sargassum macrocarpum, and the molecular mechanisms underlying ACE inhibition. Four fractions of S. macrocarpum were prepared using hexane, chloroform, ethyl acetate, and water as solvents and analyzed for their potential ACE-inhibitory effects. The chloroform fraction showed the strongest ACE-inhibitory effect, with an IC50 value of 0.18 mg/mL. Three meroterpenoids, sargachromenol, 7-methyl sargachromenol, and sargaquinoic acid, were isolated from the chloroform fraction. Meroterpenoids isolated from S. macrocarpum had IC50 values of 0.44, 0.37, and 0.14 mM. The molecular docking study revealed that the ACE-inhibitory effect of the isolated meroterpenoids was mainly attributed to Zn-ion, hydrogen bonds, pi-anion, and pi-alkyl interactions between the meroterpenoids and ACE. These results suggest that S. macrocarpum could be a potential raw material for manufacturing antihypertensive nutraceutical ingredients.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Sargassum , Inibidores da Enzima Conversora de Angiotensina/química , Simulação de Acoplamento Molecular , Sargassum/química , Peptidil Dipeptidase A/química , Clorofórmio
3.
Curr Issues Mol Biol ; 44(11): 5815-5826, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36421679

RESUMO

Sargassum horneri is a seaweed species with diverse bioactivities. However, its antifibrotic effects during nasal polyp (NP) formation are not clearly understood. Therefore, we investigated the inhibitory effect of S. horneri on fibrosis progression in NP-derived fibroblasts (NPDFs) and NP tissues ex vivo. NPDFs were stimulated with TGF-ß1 in the presence or absence of S. horneri ethanol extract (SHE). The extracellular matrix (ECM) protein production levels, myofibroblast differentiation (α-smooth muscle actin, α-SMA), and phosphorylation of Smad 2/3 and -ERK in TGF-ß1-stimulated NPDFs were investigated using western blotting. Further, the contractile activity of SHE was assessed by performing a collagen gel contraction assay. The expression levels of collagen-1, fibronectin, and α-SMA were investigated in NP organ cultures treated with SHE. TGF-ß1 stimulated ECM protein expression, myofibroblast differentiation, and collagen contractile activity while these were attenuated by pretreatment with SHE. We also found antifibrotic effect of SHE on ex vivo NP tissues. The antifibrotic effects of SHE were modulated through the attenuation of Smad 2/3 and ERK signaling pathways in TGF-ß1-stimulated NPDFs. In conclusion, SHE inhibited ECM protein accumulation and myofibroblast differentiation during NP remodeling. Thus, SHE may be helpful as a treatment for NP recurrence after endoscopic sinus surgery.

4.
Mar Drugs ; 20(6)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35736156

RESUMO

The aim of this study was to assess the potential hypertensive effects of the IGTGIPGIW peptide purified from Hippocampus abdominalis alcalase hydrolysate (HA) for application in the functional food industry. We investigated the antihypertensive effects of IGTGIPGIW in vitro by assessing nitric oxide production in EA.hy926 endothelial cells, which is a major factor affecting vasorelaxation. The potential vasorelaxation effect was evaluated using 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate, a fluorescent stain. IGTGIPGIW significantly increased the expression of endothelial-derived relaxing factors, including endothelial nitric oxide synthase and protein kinase B, in EA.hy926 cells. Furthermore, oral administration of IGTGIPGIW significantly lowered the systolic blood pressure (183.60 ± 1.34 mmHg) and rapidly recovered the diastolic blood pressure (143.50 ± 5.55 mmHg) in the spontaneously hypertensive rat model in vivo. Our results demonstrate the antihypertensive activity of the IGTGIPGIW peptide purified from H. abdominalis and indicate its suitability for application in the functional food industry.


Assuntos
Anti-Hipertensivos , Óxido Nítrico Sintase Tipo III , Smegmamorpha , Animais , Anti-Hipertensivos/farmacologia , Pressão Sanguínea , Células Endoteliais , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Peptídeos/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Endogâmicos SHR
5.
Mar Drugs ; 20(8)2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35892939

RESUMO

Ecklonia maxima is a brown seaweed, which is abundantly distributed in South Africa. This study investigated an efficient approach using high-performance centrifugal partition chromatography (HPCPC), which has been successfully developed for the isolation and purification of phlorotannins, eckmaxol, and dieckol from the ethyl acetate fraction of E. maxima (EEM). We evaluated EEM for its inhibitory effect against lipopolysaccharide (LPS)-induced inflammatory responses in zebrafish embryos. The separation of eckmaxol and dieckol from samples of EEM using HPCPC was found to be of high purity and yield under an optimal solvent system composed of n-hexane:ethyl acetate:methanol:water (2:7:3:7, v/v/v/v). To evaluate the anti-inflammatory efficacy of EEM containing active compounds, zebrafish embryos exposed to LPS were compared with and without EEM treatment for nitric oxide (NO) production, reactive oxygen species (ROS) generation, and cell death two days after fertilization. These evaluations indicate that EEM alleviated inflammation by inhibiting cell death, ROS, and NO generation induced by LPS treatment. According to these results, eckmaxol and dieckol isolated from brown seaweed E. maxima could be considered effective anti-inflammatory agents as pharmaceutical and functional food ingredients.


Assuntos
Phaeophyceae , Alga Marinha , Animais , Anti-Inflamatórios/farmacologia , Cromatografia Líquida , Lipopolissacarídeos/farmacologia , Óxido Nítrico/metabolismo , Phaeophyceae/química , Espécies Reativas de Oxigênio/metabolismo , Alga Marinha/metabolismo , África do Sul , Peixe-Zebra/metabolismo
6.
Mar Drugs ; 19(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34564159

RESUMO

In this study, we isolated sargachromenol (SC) from Sargassum horneri and evaluated its anti-inflammatory effect in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. SC did not show cytotoxicity at all concentrations and effectively increased the cell viability by reducing the nitric oxide (NO) and intracellular reactive oxygen species (ROS) production in LPS-stimulated RAW 264.7 macrophages. In addition, SC decreased the mRNA expression levels of inflammatory cytokines (IL-1ß, IL-6, and TNF-α) and inflammatory mediators (iNOS and COX-2). Moreover, SC suppressed the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) and mitogen-activated protein kinase (MAPK) signaling, whereas activated the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) signaling in LPS-stimulated RAW 264.7 macrophages. Interestingly, the anti-inflammatory effect of SC was abolished by the inhibition of HO-1 in LPS-stimulated RAW 264.7 macrophages. According to the results, this study suggests that the antioxidant capacity of SC leads to its anti-inflammatory effect and it potentially may be utilized in the nutraceutical and pharmaceutical sectors.


Assuntos
Anti-Inflamatórios/farmacologia , Benzopiranos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Sargassum , Animais , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Lipopolissacarídeos , Camundongos , NF-kappa B/metabolismo , Células RAW 264.7
7.
Mar Drugs ; 19(2)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557339

RESUMO

Grateloupia elliptica (G. elliptica) is a red seaweed with antioxidant, antidiabetic, anticancer, anti-inflammatory, and anticoagulant activities. However, the anti-obesity activity of G. elliptica has not been fully investigated. Therefore, the effect of G. elliptica ethanol extract on the suppression of intracellular lipid accumulation in 3T3-L1 cells by Oil Red O staining (ORO) was evaluated. Among the eight red seaweeds tested, G. elliptica 60% ethanol extract (GEE) exhibited the highest inhibition of lipid accumulation. GEE was the only extract to successfully suppress lipid accumulation among ethanol extracts from eight red seaweeds. In this study, we successfully isolated chlorophyll derivative (CD) from the ethyl acetate fraction (EA) of GEE by high-performance liquid chromatography and evaluated their inhibitory effect on intracellular lipid accumulation in 3T3-L1 adipocytes. CD significantly suppressed intracellular lipid accumulation. In addition, CD suppressed adipogenic protein expression such as sterol regulatory element-binding protein-1 (SREBP-1), peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding protein-α (C/EBP-α), and fatty acid binding protein 4 (FABP4). Taken together, our results indicate that CD from GEE inhibits lipid accumulation by suppressing adipogenesis via the downregulation of adipogenic protein expressions in the differentiated adipocytes. Therefore, chlorophyll from G. elliptica has a beneficial effect on lipid metabolism and it could be utilized as a potential therapeutic agent for preventing obesity.


Assuntos
Adipogenia/efeitos dos fármacos , Clorofila/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Alga Marinha , Células 3T3-L1 , Animais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Clorofila/análogos & derivados , Clorofila/uso terapêutico , Cromatografia Líquida de Alta Pressão , Regulação para Baixo , Proteínas de Ligação a Ácido Graxo/genética , Camundongos , Obesidade/tratamento farmacológico , PPAR gama/genética , Alga Marinha/química , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
8.
Pflugers Arch ; 470(9): 1325-1333, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29855712

RESUMO

We investigated the alterations of ATP-sensitive K+ (KATP) channels in human umbilical arterial smooth muscle cells during gestational diabetes mellitus (GDM). The amplitude of the KATP current induced by application of the KATP channel opener pinacidil (10 µM) was reduced in the GDM group than in the control group. Pinacidil-induced vasorelaxation was also predominant in the normal group compared with the GDM group. Reverse transcription polymerase chain reaction and Western blot analysis suggested that the expression of KATP channel subunits such as Kir6.1, Kir6.2, and SUR2B were decreased in the GDM group relative to the normal group. The application of forskolin and adenosine, which activates protein kinase A (PKA) and thereby KATP channels, elicited KATP current in both the normal and GDM groups. However, the current amplitudes were not different between the normal and GDM groups. In addition, the expression levels of PKA subunits were not altered between the two groups. These results suggest that the reduction of KATP current and KATP channel-induced vasorelaxation are due to the decreased expression of KATP channels, not to the impairment of KATP-related signaling pathways.


Assuntos
Trifosfato de Adenosina/metabolismo , Artérias/metabolismo , Diabetes Gestacional/metabolismo , Canais KATP/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Adenosina/metabolismo , Artérias/efeitos dos fármacos , Colforsina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Feminino , Humanos , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Pinacidil/farmacologia , Gravidez , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
9.
J Pharmacol Sci ; 137(1): 61-66, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29752209

RESUMO

We investigated the effect of the tricyclic antidepressant clomipramine on voltage-dependent K+ (Kv) channels in native rabbit coronary arterial smooth muscle cells. Our results showed that clomipramine inhibited vascular Kv channels in a concentration-dependent manner, with an IC50 value of 8.61 ± 4.86 µM and a Hill coefficient (n) of 0.58 ± 0.07. The application of 10 µM clomipramine did not affect the activation curves of the Kv channels; however, the inactivation curves of the Kv channels were shifted toward a more negative potential. The clomipramine-induced inhibition of Kv currents was not changed by the application of train pulses (1 or 2 Hz), which demonstrated that clomipramine inhibited Kv current in a state (use)-independent manner. Pretreatment with the Kv1.5 and Kv2.1 inhibitors, DPO-1 and guangxitoxin, respectively, partially reduced the clomipramine-induced inhibition of Kv currents. Therefore, we concluded that clomipramine inhibited vascular Kv channels in a concentration-dependent, but state (use)-independent manner, regardless of its own function.


Assuntos
Antidepressivos Tricíclicos/farmacologia , Clomipramina/farmacologia , Vasos Coronários/citologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Canais de Potássio de Abertura Dependente da Tensão da Membrana/antagonistas & inibidores , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Masculino , Coelhos
10.
Clin Exp Pharmacol Physiol ; 45(2): 205-212, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28945283

RESUMO

Amitriptyline, a tricyclic antidepressant (TCA) drug, is widely used in treatment of psychiatric disorders. However, the side effects of amitriptyline on vascular K+ channels remain to be determined. Therefore, we investigated the effect of the tricyclic antidepressant and serotonin reuptake inhibitor amitriptyline on voltage-dependent K+ (Kv) channels in freshly isolated rabbit coronary arterial smooth muscle cells, using the whole-cell patch clamp technique. The Kv current amplitudes were inhibited by amitriptyline in a concentration-dependent manner, with an apparent IC50 value of 2.2 ± 0.14 µmol/L and a Hill coefficient of 0.87 ± 0.03. Amitriptyline shifted the activation curve to a more positive potential, but had no significant effect on the inactivation curve, suggesting that amitriptyline altered the voltage sensitivity of Kv channels. Pretreatment with Kv1.5 and Kv1.2 channel inhibitors did not alter the inhibitory effect of amitriptyline on Kv channels. Additionally, application of train pulses (1 and 2 Hz) did not affect amitriptyline-induced inhibition of Kv currents, which suggested that the action of amitriptyline on Kv channels was not use (state)-dependent. From these results, we concluded that amitriptyline inhibited the channels in a concentration-dependent, but state-independent manner.


Assuntos
Amitriptilina/farmacologia , Vasos Coronários , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Bloqueadores dos Canais de Potássio , Animais , Antidepressivos Tricíclicos/farmacologia , Canais de Potássio/metabolismo , Coelhos
11.
Int J Mol Sci ; 19(8)2018 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-30087236

RESUMO

Osteoarthritis (OA) is a degenerative joint disease that is characterized by irreversible articular cartilage destruction by inflammatory reaction. Among inflammatory stimuli, interleukin-1ß (IL-1ß) is known to play a crucial role in OA pathogenesis by stimulating several mediators that contribute to cartilage degradation. Recently, the marine brown alga Sargassum serratifolium has been reported to exhibit antioxidant and anti-inflammatory effects in microglial and human umbilical vein endothelial cell models using lipopolysaccharide and tumor necrosis factor-α, but its beneficial effects on OA have not been investigated. This study aimed to evaluate the anti-osteoarthritic effects of ethanol extract of S. serratifolium (EESS) in SW1353 human chondrocytes and, in parallel, primary rat articular chondrocytes. Our results showed that EESS effectively blocked the generation of reactive oxygen species in IL-1ß-treated SW1353 and rat primary chondrocytes, indicating that EESS has a potent antioxidant activity. EESS also attenuated IL-1ß-induced production of nitric oxide (NO) and prostaglandin E2, major inflammatory mediators in these cells, which was associated with the inhibition of inducible NO synthase and cyclooxygenase-2 expression. Moreover, EESS downregulated the level of gene expression of matrix metalloproteinase (MMP)-1, -3 and -13 in SW1353 chondrocytes treated with IL-1ß, resulting in their extracellular secretion reduction. In addition, the IL-1ß-induced activation of nuclear factor-kappa B (NF-κB) was restored by EESS. Furthermore, EESS reduced the activation of p38 mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathways upon IL-1ß stimulation. These results indicate that EESS has the potential to exhibit antioxidant and anti-inflammatory effects through inactivation of the NF-κB, p38 MAPK, and PI3K/Akt signaling pathways. Collectively, these findings demonstrate that EESS may have the potential for chondroprotection, and extracts of S. serratifolium could potentially be used in the prevention and treatment of OA.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Condrócitos/efeitos dos fármacos , Interleucina-1beta/imunologia , Extratos Vegetais/farmacologia , Sargassum , Animais , Anti-Inflamatórios/química , Antioxidantes/química , Linhagem Celular , Células Cultivadas , Condrócitos/imunologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Masculino , NF-kappa B/imunologia , Osteoartrite/tratamento farmacológico , Osteoartrite/imunologia , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/imunologia , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-akt/imunologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/imunologia , Sargassum/química , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia
12.
Mar Drugs ; 15(6)2017 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-28555064

RESUMO

It is well known that fucoidan, a natural sulfated polysaccharide present in various brown algae, mediates anticancer effects through the induction of cell cycle arrest and apoptosis. Nevertheless, the role of tumor suppressor p53 in the mechanism action of fucoidan remains unclear. Here, we investigated the anticancer effect of fucoidan on two p53 isogenic HCT116 (p53+/+ and p53-/-) cell lines. Our results showed that inhibition of cell viability, induction of apoptosis and DNA damage by treatment with fucoidan were similar in two cell lines. Flow cytometric analysis revealed that fucoidan resulted in G1 arrest in the cell cycle progression, which correlated with the inhibition of phosphorylation of retinoblastoma protein (pRB) and concomitant association of pRB with the transcription factor E2Fs. Furthermore, treatment with fucoidan obviously upregulated the expression of cyclin-dependent kinase (CDK) inhibitors, such as p21WAF1/CIP1 and p27KIP1, which was paralleled by an enhanced binding with CDK2 and CDK4. These events also commonly occurred in both cell lines, suggesting that fucoidan triggered G1 arrest and apoptosis in HCT116 cells by a p53-independent mechanism. Thus, given that most tumors exhibit functional p53 inactivation, fucoidan could be a possible therapeutic option for cancer treatment regardless of the p53 status.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Fase G1/efeitos dos fármacos , Polissacarídeos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Dano ao DNA/efeitos dos fármacos , Fatores de Transcrição E2F/metabolismo , Células HCT116 , Humanos , Fosforilação/efeitos dos fármacos , Proteína do Retinoblastoma/metabolismo , Regulação para Cima/efeitos dos fármacos
13.
J Environ Biol ; 37(1): 129-34, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26930870

RESUMO

Traditional medicinal plants contain a wide variety of chemicals that have potent antibacterial activity. To find an alternative agent of overcoming the problems of methicillin-resistant Staphylococcus aureus (MRSA), the antibacterial mechanism of Ponciruss trifoliata against MRSA was investigated. Ethyl acetate (EtOAc)-soluble extract of P. trifoliata methanolic extract was evaluated for antibacterial activity using minimum inhibitory concentration (MIC). An EtOAc sub-fraction 08 (EA08) from silica-gel open column chromatography exhibited strong anti-MRSA activity. Apart from the study to isolate single compound from EA08, a synergistic antibacterial effect between the sub-fraction and ß-lactam antibiotics against MRSA was determined. In order to elucidate the antibacterial restoring mechanism of EA08 on MRSA, mRNA expression of mecA gene and production penicillin-binding protein 2a (PBP2a) encoded by mecA gene were monitored. EA 08 showed the strongest antibacterial activity with MIC value of 256 µg ml(-1). MIC of oxacillin against MRSA was dramatically reduced from 512 to 16 µg ml(-1) in combination with 256 µg ml(-1) of EA08. The fractional inhibitory concentration index of oxacillin was measured at 0.53 in combination with EA08 against MRSA, suggesting that EA08-oxacillin combinations exert synergetic effect against MRSA. The analysis of RT-PCR and Western blotting profiles revealed that EA08 inhibited mRNA expression of mecA gene and production PBP2a, which is a key determinant for ß-lactam antibiotic resistance, in a dose-dependent manner. These results indicated that EA08 eventually led to the reduction or inhibition of PBP2a production through translational inhibition in MRSA.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Poncirus/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Plantas Medicinais
14.
Appl Microbiol Biotechnol ; 98(23): 9795-804, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25267155

RESUMO

To find more effective ways of overcoming methicillin-resistant Staphylococcus aureus (MRSA), there has been considerable interest in the use of marine-derived constituents as alternatives to control pathogenic microorganisms. In this study, we investigated whether phlorofucofuroeckol-A (PFF) isolated from the edible brown alga Eisenia bicyclis suppressed production or function of penicillin-binding protein 2a (PBP2a). The antimicrobial mode of action of PFF in MRSA was identified by measuring cell membrane integrity and using the time-kill curve method. We attempted to determine the antimicrobial effects of PFF on the expression level of the resistance determinants mecA and its regulatory genes mecI and mecR1 in MRSA by reverse transcriptase polymerase chain reaction. PFF suppressed mecI, mecR1, and mecA gene expression in a dose-dependent manner. In addition, we revealed PFF mediates the suppressive effect of PBP2a expression in MRSA by Western blot analysis. PFF suppressed production of the PBP2a protein, suggesting that PFF probably acts by controlling the methicillin resistance-associated genes involved in the cell wall and production of PBP2a. These results demonstrate that PFF isolated from E. bicyclis significantly suppressed the expression of the methicillin resistance-associated genes and production of PBP2a, which is considered the primary cause of methicillin resistance.


Assuntos
Antibacterianos/farmacologia , Benzofuranos/farmacologia , Dioxinas/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Proteínas de Ligação às Penicilinas/antagonistas & inibidores , Antibacterianos/isolamento & purificação , Proteínas de Bactérias/biossíntese , Benzofuranos/isolamento & purificação , Western Blotting , Dioxinas/isolamento & purificação , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Phaeophyceae/química , Proteínas Repressoras/biossíntese
15.
Can J Microbiol ; 60(10): 629-38, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25216286

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is spreading worldwide, emphasizing the need to search for new antibiotics. The anti-MRSA activities of gallic acid-grafted-chitosans (GA-g-chitosans) were investigated against 2 MRSA standards and 10 MRSA clinical isolates by determining the minimum inhibitory concentrations (MICs). GA-g-chitosan (I), which has the highest gallic acid content, exhibited the strongest anti-MRSA activities, with MICs of 32-64 µg/mL. A time-kill investigation revealed that GA-g-chitosan (I) exhibited a bactericidal effect at twice the MIC, also demonstrating good thermal and pH stability. Investigation of cell envelope integrity showed the release of intracellular components with an increasing absorbance value at 260 nm, indicating cell envelope damage caused by the GA-g-chitosan (I), which was further confirmed by transmission electron microscopy. When GA-g-chitosans were combined with ß-lactams, including ampicillin and penicillin, synergistic effects were observed on the 2 standard MRSA strains and on the 10 clinical isolates, with fractional inhibitory indices ranging from 0.125 to 0.625. In the time-kill dynamic confirmation test, synergistic bactericidal effects were observed for the combinations of GA-g-chitosans with ß-lactams, and over 4.0 log CFU/mL reductions were observed after 24 h when combination treatment was used. These results may prove GA-g-chitosans to be a potent agent when combined with ampicillin and penicillin for the elimination of MRSA.


Assuntos
Quitosana/química , Quitosana/farmacologia , Ácido Gálico/química , Ácido Gálico/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , beta-Lactamas/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Contagem de Colônia Microbiana , Estabilidade de Medicamentos , Sinergismo Farmacológico , Temperatura Alta , Concentração de Íons de Hidrogênio , Staphylococcus aureus Resistente à Meticilina/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão
16.
Int J Biol Macromol ; 269(Pt 2): 131927, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38685538

RESUMO

The accumulation of methylglyoxal (MGO) produced in high-temperature processed foods and excessive production in the body contributes to intestinal barrier dysfunction. In this study, we investigated the effects of chitooligosaccharides (COSs) of different molecular weights (<1 kDa, 1-3 kDa, 3-5 kDa, 5-10 kDa, and >10 kDa) on MGO-induced intestinal barrier dysfunction. We investigated the effect of COSs on inhibiting intracellular MGO accumulation/MGO-derived AGEs production and regulating the receptor for AGE (RAGE)-mediated downstream protein expression, including proteins related to apoptosis and inflammation, intestinal barrier integrity, and paracellular permeability. Pretreatment with COSs ameliorated MGO-induced increased RAGE protein expression, activation of apoptotic cascade/inflammatory response, loss of intestinal epithelial barrier integrity, and increased paracellular permeability, ameliorating intestinal dysfunction through MGO scavenging. 1-3 kDa COSs most effectively ameliorated MGO-induced intestinal dysfunction. Our results suggest the potential of COSs in improving intestinal health by ameliorating intestinal barrier dysfunction by acting as an MGO scavenger and highlighting the need for the optimization of the molecular weight of COSs to optimize its protective effects.


Assuntos
Quitosana , Produtos Finais de Glicação Avançada , Mucosa Intestinal , Peso Molecular , Oligossacarídeos , Aldeído Pirúvico , Receptor para Produtos Finais de Glicação Avançada , Oligossacarídeos/farmacologia , Oligossacarídeos/química , Produtos Finais de Glicação Avançada/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Quitosana/farmacologia , Quitosana/química , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Humanos , Intestinos/efeitos dos fármacos , Intestinos/patologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/induzido quimicamente , Apoptose/efeitos dos fármacos , Quitina/farmacologia , Quitina/análogos & derivados , Quitina/química , Permeabilidade/efeitos dos fármacos
17.
Int J Biol Macromol ; 255: 128047, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37956810

RESUMO

The design and development of wound dressing with antioxidant and antibacterial properties to accelerate wound healing remain challenging. In this study, we synthesize a chitooligosaccharide-gentisic acid (COS-GSA) conjugate using the free-radical grafting method, and fabricate a poly(vinyl alcohol) (PVA)/chitosan (CH)/COS-GSA (PVA/CH/CG) hydrogel using a freeze-thaw method. We characterize the synthesized COS-GSA conjugates using through polyphenol assay, absorbance, and 1H NMR spectroscopy and evaluate their antioxidant properties. The COS-GSA conjugates are successfully synthesized and exhibit better antioxidant properties than pristine COSs. Subsequently, the fabricated hydrogel is characterized based on its morphological analysis, rheological properties, water contact angle, swelling, degradation, water retention properties, and COS-GSA release profiles. Finally, the biocompatibility of the fabricated hydrogel is evaluated on HDF and HaCaT cells through indirect and direct cytotoxicity. The PVA/CH/CG hydrogel exhibited significantly higher antioxidant properties (DPPH, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and hydrogen peroxide (H2O2) scavenging activities) and antibacterial activities (Staphylococcus aureus and Pseudomonas aeruginosa) compared to other fabricated hydrogels such as PVA, PVA/CH, and PVA/CH/COS (PVA/CH/C). These results provide evidence that PVA/CH/CG hydrogels with antioxidant, antibacterial, and non-cytotoxic properties have great potential for wound-dressing applications.


Assuntos
Quitosana , Quitosana/química , Antioxidantes/farmacologia , Álcool de Polivinil/química , Hidrogéis/química , Peróxido de Hidrogênio , Antibacterianos/farmacologia , Antibacterianos/química , Bandagens , Água , Etanol
18.
J Microbiol Biotechnol ; 34(8): 1688-1697, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39086228

RESUMO

The current study aimed to determine whether Strongylocentrotus intermedius (S. intermedius) extract (SIE) exerts anti-obesity potentials employing 3T3-L1 cells as in vitro model. Herein we reported that treatment of SIE for 6 days reduced lipid accretion and triglyceride content whereas it increased the release of free glycerol. The inhibited lipid accumulation and induced lipolysis were evidenced by the downregulation of lipogenesis proteins, such as fatty acid synthase and lipoprotein lipase, and the upregulation of hormone-sensitive lipase expression. Furthermore, the downregulation of adipogenic transcription factors, including peroxisome proliferator-activated receptor gamma, CCAAT/enhancer-binding protein α, and sterol regulatory element-binding protein 1, highlights that reduced lipid accumulation is supported by lowering adipocyte differentiation. Additionally, treatment activates brown adipocyte phenotype in 3T3-L1 cells by inducing expression of brown adipose tissue-specific proteins, such as uncoupling protein 1 and peroxisome proliferator-activated receptor-γ coactivator 1α. Moreover, SIE induced the phosphorylation of AMP-activated protein kinase (AMPK). The pharmacological approach using AMPK inhibitor revealed that the restraining effect of SIE on adipogenesis and promotion of adipocyte browning were blocked. In GC-MS analysis, SIE was mainly composed of cholest-5-en-3-ol (36.71%) along with saturated and unsaturated fatty acids which have favorable anti-obesity potentials. These results reveal that SIE has the possibility as a lipid-lowering agent for the intervention of obesity.


Assuntos
Células 3T3-L1 , Proteínas Quinases Ativadas por AMP , Adipogenia , Animais , Adipogenia/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Lipólise/efeitos dos fármacos , PPAR gama/metabolismo , PPAR gama/genética , Adiposidade/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Adipócitos Marrons/efeitos dos fármacos , Adipócitos Marrons/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Triglicerídeos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Fosforilação/efeitos dos fármacos
19.
Food Chem ; 407: 135130, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36527945

RESUMO

In this study, seahorse peptide (SHP) was isolated from an alcalase-treated hydrolysate from Hippocampus abdominalis and assessed for its antioxidant potential against AAPH-induced oxidative stress damage. AAPH stimulation significantly decreased cell viability and increased intracellular reactive oxygen species (ROS) production in Vero cells. SHP treatment increased cell viability and remarkably lowered ROS production under AAPH-induced oxidative stress. Furthermore, it protected against AAPH-induced apoptotic DNA damage. Western blot analysis demonstrated that SHP treatment remarkably increased the protein expression levels of catalase and SOD in AAPH-induced Vero cells. A zebrafish study revealed that SHP-treated zebrafish embryos resulted in lower cell death, ROS generation, and lipid peroxidation than the AAPH-treated group. These results suggest that SHP is a potent functional antioxidant that could be developed as a natural antioxidant in the food and functional food industries.


Assuntos
Antioxidantes , Smegmamorpha , Animais , Chlorocebus aethiops , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Células Vero , Smegmamorpha/genética , Smegmamorpha/metabolismo , Estresse Oxidativo , Peptídeos/farmacologia , Peptídeos/metabolismo
20.
Nutrients ; 12(9)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867396

RESUMO

Acne vulgaris is a chronic inflammatory condition of skin sebaceous follicles. To explore its effects on acne vulgaris, we investigated the antibacterial and anti-inflammatory activities of Sargassum miyabei Yendo (a brown alga) ethanolic extract (SMYEE) on Cutibacterium acnes (C. acnes)-stimulated inflammatory responses, both in vivo and in vitro. To induce inflammation in vivo, C. acnes was intradermally injected into the dorsal skin of mice, to which SMYEE was applied. The antimicrobial activity of SMYEE was evaluated by the determination of minimum inhibitory concentrations (MICs). To explore in vitro anti-inflammatory effects, HaCaT cells were stimulated with C. acnes after treatment with SMYEE. The levels of IL-8 and the underlying molecular effects in C. acnes-stimulated HaCaT cells were assessed by enzyme-linked immunosorbent assay, Western blotting, and an electrophoretic mobility shift assay. Mouse skin lesions improved after treatment with SMYEE (50 µg/mouse). Neutrophil infiltration was significantly reduced in SMYEE-treated compared to SMYEE-untreated skin lesions. SMYEE reversed the C. acnes-induced increase in IL-8 levels in HaCaT cells and suppressed dHL-60 cell migration. SMYEE also inhibited C. acnes-induced phosphorylation of the extracellular signal-regulated kinase and inhibited activator protein-1 signaling. SMYEE may be a useful treatment for C. acnes-induced acne vulgaris.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Dermatite/tratamento farmacológico , Propionibacteriaceae/efeitos dos fármacos , Sargassum , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos ICR , Pele/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA