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1.
Lett Appl Microbiol ; 72(3): 238-244, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33064844

RESUMO

The present study evaluated the antibacterial activity and the synergy of the sanguisorbigenin (SGB) from the dried root of Sanguisorba officinalis L. combined with ß-lactam antibiotics against methicillin-resistant Staphylococcus aureus. A total of six strains of reference strain and clinical isolates were used to determine the antibacterial activity using a broth microdilution assay, and the synergistic effects were determined using a checkerboard assay. To analyse the mechanism of synergy, we conducted the level of penicillin-binding protein 2a by western blot. In addition, quantitative RT-PCR was performed to analyse the mecA gene expression. The minimal inhibitory concentration values of SGB against six strains of S. aureus were in the range of 12·5-50 µg ml-1 , and there were synergy, or partial synergy effects when SGB was combined with antibiotics. Furthermore, when treated with SGB, the level of penicillin-binding protein 2a and the expression of the mecA gene was reduced significantly. In conclusion, this study demonstrated that SGB is a potential natural antibacterial agent against methicillin-resistant S. aureus that represents a considerable burden on the healthcare system worldwide, and may an exceptionally modulator of ß-lactam antibiotics.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Preparações de Plantas/farmacologia , Proteínas de Bactérias/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas/metabolismo , Raízes de Plantas/química , Sanguisorba/química
2.
Lett Appl Microbiol ; 72(6): 669-676, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32955753

RESUMO

Acanthopanax (A.) henryi (Oliv.) Harms contain many bioactive compounds commonly used in traditional Chinese medicine. The objective of the present study was to investigate the antibacterial activity of the single constituent, Eleutheroside K (ETSK) isolated from the leaves of A. henryi (Oliv.) Harms, against methicillin-resistant Staphylococcus (S.) aureus (MRSA). Broth microdilution assay was used to measure the minimal inhibitory concentration (MIC) and the MIC values of ETSK against eight clinical S. aureus strains were all 50 µg ml-1 . At sub-inhibitory concentrations, a synergistic effect between oxacillin (OXA) and ETSK was confirmed using checkerboard dilution assay and time-kill curve analysis. The bacteriostatic effect became more pronounced when ETSK was used in combination with detergent (Triton X-100) or ATPase inhibitor (N, N'-dicyclohexylcarbodiimide). According to western blot analysis, the down-regulated expression of Penicillin-binding protein 2a (PBP2a) further validated that the bacterial activity was inhibited when treated with ETSK in a dose-dependent manner. Results based on our study verified that ETSK significantly suppressed MRSA infections and emphasized the potential application of ETSK as a novel anti-MRSA natural drug.


Assuntos
Antibacterianos/farmacologia , Eleutherococcus/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Oxacilina/farmacologia , Extratos Vegetais/farmacologia , Dicicloexilcarbodi-Imida/farmacologia , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Quimioterapia Combinada , Eleutherococcus/química , Resistência a Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Octoxinol/farmacologia , Proteínas de Ligação às Penicilinas/biossíntese , Folhas de Planta/química
3.
Eur Rev Med Pharmacol Sci ; 16 Suppl 3: 121-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22957426

RESUMO

BACKGROUND AND OBJECTIVES: Papaveraceae serve as a rich source of various alkaloids which have anti-inflammatory effect. MATERIALS AND METHODS: In this study, we investigated the effect of Hylomecon hylomeconoides ethanol extract (HHE) on lipopolysaccharide (LPS)-induced NO and interleukin-6 (IL-6) production in RAW 264.7 cells. RESULTS: HHE inhibited LPS-induced NO and IL-6 production. Moreover, HHE suppressed the phosphorylation of ERK1/2 and p38 in LPS-induced RAW 264.7 in a dose-dependent manner. Furthermore, major constituents, dihydrosanguinarine and 6-methoxydihydrosanguinarine, of the chloroform-soluble extract were analyzed. CONCLUSIONS: Taken together, the results of this study indicate that the anti-inflammatory effects of HHE may occur via the inhibition of NO and IL-6 expression through the down-regulation of MAP kinase (ERK1/2, p38) phosphorylation in RAW 264.7 cells.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Papaveraceae/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Inflamação/fisiopatologia , Interleucina-6/metabolismo , Lipopolissacarídeos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/metabolismo , Fosforilação/efeitos dos fármacos , Extratos Vegetais/administração & dosagem
4.
Eur Rev Med Pharmacol Sci ; 16(7): 853-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22953631

RESUMO

BACKGROUND AND OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA) infections are a rapidly growing health problem around the globe. Recently, there has been considerable interest in the use of plant materials as an alternative method to control pathogenic microorganisms. In this study we evaluated the antibacterial activity of bark of Alnus pendula against MRSA. MATERIALS AND METHODS: The MIC determination was done using the microdilution broth method and bacterial growth was determined by measuring optical density using spectrophotometer. RESULTS: Alnus pendula bark EtOH extract and fractions (F-1, -2, -3 and -4) were investigated against MRSA. The most active fractions (F-3 and F-4) led to the isolation of oregonin (ORE) and hirsutanone (HIR). These compounds were active against MRSA strains with minimum inhibitory concentrations (MICs) ranging from 31.25 to 250 microg/ml MIC and 2 MIC of HIR completely inhibited the growth of MRSA. CONCLUSIONS: The bark EtOH extract of Alnus Pendula has potent antibacterial activity against MRSA.


Assuntos
Alnus , Antibacterianos/farmacologia , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alnus/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Diarileptanoides/farmacologia , Etanol/química , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Casca de Planta , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Solventes/química , Espectrofotometria
5.
AJNR Am J Neuroradiol ; 32(4): 682-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21330396

RESUMO

BACKGROUND AND PURPOSE: Loss of dopaminergic neurons in the nigrostriatal pathway is well-documented in PD, whereas neuronal changes beyond the nigrostriatal pathway are uncertain. The purpose of our study was to estimate volume changes in the striatum and thalamus, which are areas of the basal ganglia, as well as in GM and WM located beyond the nigrostriatal pathway, in early-stage PD. MATERIALS AND METHODS: We enrolled 30 participants (15 healthy controls and 15 patients with PDND with H & Y stage I or II). Cognitive function was assessed by using the MMSE. ICV and the volumes of the caudate nucleus, putamen, thalamus, GM, and WM were calculated via 3D volume analysis by using MR imaging. RESULTS: A comparison of the PD group with the control group revealed an absence of significant differences between them regarding age and MMSE scores. Comparison of the volumes of regional brain structures of patients with PD with those of controls revealed the presence of significant differences in the caudate nucleus, thalamus, and WM (P<.05) between the groups. However, there were no significant differences in the volumes of the putamen and GM or in ICV between patients with PD and controls. The results of ANCOVA by using the covariates of age and ICV showed a significant difference in the caudate nucleus, thalamus, and WM between patients with PD and controls (P<.05). CONCLUSIONS: We suggest that loss of WM volume may occur in early disease stages and that variation of the volumes of the caudate nucleus and thalamus may be an early phenomenon of disease progression.


Assuntos
Corpo Estriado/patologia , Imageamento por Ressonância Magnética , Doença de Parkinson/patologia , Tálamo/patologia , Idoso , Núcleo Caudado/patologia , Progressão da Doença , Diagnóstico Precoce , Feminino , Globo Pálido/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas Mielinizadas/patologia , Neurônios/patologia , Putamen/patologia
6.
Eur Rev Med Pharmacol Sci ; 14(12): 1005-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21375130

RESUMO

BACKGROUND AND OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA) has been a serious problem as its infection is associated with higher mortality and increase cost worldwide. In the present study, the antibacterial activity of enhydrin, polymatin B, allo-schkuhriolide from the leaves of Smallanthus sonchifolius was investigated. MATERIAL AND METHODS: Enhydrin, polymatin B, allo-schkuhriolide from the leaves of Smallanthus sonchifolius were tested for antimicrobial activity using micro dilution broth method against 2 strains of ATCC 33591, ATCC 25923 and 15 strains of clinical isolates MRSA. RESULTS: The antibacterial activity of Smallanthus sonchifolius can safely be attributed to enhydrin as polymatin B, and allo-schkuhriolide are not showing any activity against Staphylococcus aureus strains. The enhydrin showed good antibacterial activity against all tested strains (MIC = 125-500 microg/ml). DISCUSSION: These results suggest that only enhydrin can be considered as an antibacterial drug against MRSA.


Assuntos
Antibacterianos/farmacologia , Asteraceae , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Proteínas de Bactérias/genética , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas , Folhas de Planta , Reação em Cadeia da Polimerase
7.
Fitoterapia ; 79(3): 204-6, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18191910

RESUMO

Activity-guided fractionation of the methanol extract of Vitis vinifera bark led to the isolation of epsilon-viniferin, ampelopcin A, vitisin A and vitisin B. Vitisin A and vitisin B showed a remarkable inhibitory activity against 3-hydroxy-3-methylglutaryl-Coenzyme A (HMG-CoA) reductase with IC50 value of 42.1 microM and 23.9 microM, respectively.


Assuntos
Anti-Hipertensivos/farmacologia , Hidroximetilglutaril-CoA Redutases/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Vitis , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/uso terapêutico , Escherichia coli/enzimologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Casca de Planta , Componentes Aéreos da Planta , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico
8.
Horm Metab Res ; 39(10): 752-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17952839

RESUMO

Soy protein and isoflavonoids in soybeans exhibit the improvement of insulin resistance. Our previous IN VITRO study showed that Chungkookjang (CKJ), fermented unsalted soybeans, had better antidiabetic actions than cooked unfermented soybeans (CSB) by increasing isoflavones aglycones and small peptides. We investigated whether 40% fat diets with different protein sources such as CSB, CKJ, and casein modulated peripheral insulin resistance in 90% pancreatectomized (Px) diabetic rats. The Px rats weighing 209+/-14 g were freely provided casein, CSB, or CKJ diets for 8 weeks. Both CKJ and CSB increased whole body glucose disposal rates and glucose uptake into skeletal muscles of Px rats as much as rosiglitazone plus casein treated rats during euglycemic hyperinsulinemic clamp. In addition, CKJ and CSB decreased hepatic glucose output at hyperinsulinemic clamped states, compared to the Casein group. The reduction of hepatic glucose output was greater in CKJ than CSB. This reduction was associated with enhanced tyrosine phosphorylation of IRS2 and serine (473) phosphporylation of Akt, indicating improved hepatic insulin signaling. This improved signaling led to decreased phosphoenolpyruvate carboxykinase expression to reduce hepatic glucose output. In conclusion, fermented soybeans mainly with BACILLUS SUBTILIS improved hepatic insulin sensitivity better than unfermented soybeans by enhancing hepatic insulin signaling cascade in diabetic rats.


Assuntos
Diabetes Mellitus Experimental/dietoterapia , Fermentação/fisiologia , Glycine max , Resistência à Insulina , Fígado/efeitos dos fármacos , Pancreatectomia , Extratos Vegetais/farmacologia , Animais , Glicemia/efeitos dos fármacos , Caseínas/administração & dosagem , Culinária , Ingestão de Alimentos/fisiologia , Jejum/sangue , Ácidos Graxos não Esterificados/sangue , Insulina/metabolismo , Isoflavonas , Fígado/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas de Soja , Glycine max/química , Fatores de Tempo
9.
Braz J Med Biol Res ; 39(9): 1181-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16972004

RESUMO

Over the last decades, the incidence of ultraviolet B (UVB)-related skin problems has been increasing. Damages induced by UVB radiation are related to mutations that occur as a result of direct DNA damage and/or the production of reactive oxygen species. We investigated the anti-oxidant effects of a Polygonum multiflorum thumb extract against skin damage induced by UVB irradiation. Female SKH-1 hairless mice were divided into three groups: control (N = 7), distilled water- (N = 10), and P. multiflorum extract-treated (PM, N = 10) groups. The PM (10 g) was extracted with 100 mL distilled water, cryo-dried and 9.8 g was obtained. The animals received a topical application of 500 microL distilled water or PM extract (1, 2, 4, 8, and 16%, w/v, dissolved in distilled water) for 30 min after UVB irradiation (wavelength 280-320 nm, 300 mJ/cm(2); 3 min) of the dorsal kin for 14 days, and skin immunohistochemistry and Cu,Zn-superoxide dismutase (SOD1) activity were determined. SOD1 immunoreactivity, its protein levels and activities in the skin were significantly reduced by 70% in the distilled water-treated group after UVB irradiation compared to control. However, in the PM extract-treated groups, SOD1 immunoreactivity and its protein and activity levels increased in a dose-dependent manner (1-16%, w/v, PM extract) compared to the distilled water-treated group. SOD1 protein levels and activities in the groups treated with 8 and 16%, w/v, PM extract recovered to 80-90% of the control group levels after UVB. These results suggest that PM extract strongly inhibits the destruction of SOD1 by UV radiation and probably contains anti-skin photoaging agents.


Assuntos
Antioxidantes/uso terapêutico , Polygonum/química , Lesões Experimentais por Radiação/prevenção & controle , Pele/efeitos da radiação , Superóxido Dismutase/metabolismo , Raios Ultravioleta/efeitos adversos , Administração Tópica , Animais , Western Blotting , Feminino , Camundongos , Camundongos Pelados , Extratos Vegetais/uso terapêutico , Lesões Experimentais por Radiação/metabolismo , Superóxido Dismutase-1
10.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;39(9): 1181-1188, Sept. 2006. ilus, graf
Artigo em Inglês | LILACS | ID: lil-435421

RESUMO

Over the last decades, the incidence of ultraviolet B (UVB)-related skin problems has been increasing. Damages induced by UVB radiation are related to mutations that occur as a result of direct DNA damage and/or the production of reactive oxygen species. We investigated the anti-oxidant effects of a Polygonum multiflorum thumb extract against skin damage induced by UVB irradiation. Female SKH-1 hairless mice were divided into three groups: control (N = 7), distilled water- (N = 10), and P. multiflorum extract-treated (PM, N = 10) groups. The PM (10 g) was extracted with 100 mL distilled water, cryo-dried and 9.8 g was obtained. The animals received a topical application of 500 æL distilled water or PM extract (1, 2, 4, 8, and 16 percent, w/v, dissolved in distilled water) for 30 min after UVB irradiation (wavelength 280-320 nm, 300 mJ/cm²; 3 min) of the dorsal kin for 14 days, and skin immunohistochemistry and Cu,Zn-superoxide dismutase (SOD1) activity were determined. SOD1 immunoreactivity, its protein levels and activities in the skin were significantly reduced by 70 percent in the distilled water-treated group after UVB irradiation compared to control. However, in the PM extract-treated groups, SOD1 immunoreactivity and its protein and activity levels increased in a dose-dependent manner (1-16 percent, w/v, PM extract) compared to the distilled water-treated group. SOD1 protein levels and activities in the groups treated with 8 and 16 percent, w/v, PM extract recovered to 80-90 percent of the control group levels after UVB. These results suggest that PM extract strongly inhibits the destruction of SOD1 by UV radiation and probably contains anti-skin photoaging agents.


Assuntos
Animais , Feminino , Camundongos , Antioxidantes/uso terapêutico , Radicais Livres/efeitos da radiação , Polygonum/química , Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Administração Tópica , Western Blotting , Imuno-Histoquímica , Camundongos Pelados , Extratos Vegetais/uso terapêutico , Superóxido Dismutase/metabolismo
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