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1.
Prog Mol Biol Transl Sci ; 201: 93-118, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37770177

RESUMO

Phage therapy, the use of bacteriophage viruses for bacterial infection treatment, has been around for almost a century, but with the increase in antibiotic use, its importance has declined rapidly. There has been renewed interest in revisiting this practice due to the general decline in the effectiveness of antibiotics, combined with improved understanding of human microbiota and advances in sequencing technologies. Phage therapy has been proposed as a clinical alternative to restore the gut microbiota in the absence of an effective treatment. That is due to its immunomodulatory and bactericidal effects against its target bacteria. In the gastrointestinal diseases field, phage therapy has been studied mainly as a promising tool in infectious diseases treatment, such as cholera and diarrhea. However, many studies have been conducted in non-communicable diseases, such as the targeting of adherent invasive Escherichia coli in Crohn's disease, the treatment of Clostridioides difficile in ulcerative colitis, the eradication of Fusobacterium nucleatum in colorectal cancer, the targeting of alcohol-producing Klebsiella pneumoniae in non-alcoholic fatty liver disease, or Enterococcus faecalis in alcohol-associated hepatitis. This review will summarize the changes in the gut microbiota and the phageome in association with some gastrointestinal and liver diseases and highlight the recent scientific advances in phage therapy as a therapeutic tool for their treatment.


Assuntos
Microbioma Gastrointestinal , Microbiota , Terapia por Fagos , Humanos , Trato Gastrointestinal/microbiologia , Bactérias , Antibacterianos
2.
Nat Commun ; 12(1): 7172, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34887405

RESUMO

Complement receptor of immunoglobulin superfamily (CRIg) is expressed on liver macrophages and directly binds complement component C3b or Gram-positive bacteria to mediate phagocytosis. CRIg plays important roles in several immune-mediated diseases, but it is not clear how its pathogen recognition and phagocytic functions maintain homeostasis and prevent disease. We previously associated cytolysin-positive Enterococcus faecalis with severity of alcohol-related liver disease. Here, we demonstrate that CRIg is reduced in liver tissues from patients with alcohol-related liver disease. CRIg-deficient mice developed more severe ethanol-induced liver disease than wild-type mice; disease severity was reduced with loss of toll-like receptor 2. CRIg-deficient mice were less efficient than wild-type mice at clearing Gram-positive bacteria such as Enterococcus faecalis that had translocated from gut to liver. Administration of the soluble extracellular domain CRIg-Ig protein protected mice from ethanol-induced steatohepatitis. Our findings indicate that ethanol impairs hepatic clearance of translocated pathobionts, via decreased hepatic CRIg, which facilitates progression of liver disease.


Assuntos
Enterococcus faecalis/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Hepatopatias Alcoólicas/imunologia , Macrófagos/imunologia , Receptores de Complemento 3b/imunologia , Receptores de Complemento/imunologia , Animais , Translocação Bacteriana , Complemento C3b/imunologia , Enterococcus faecalis/fisiologia , Etanol/efeitos adversos , Feminino , Trato Gastrointestinal/microbiologia , Infecções por Bactérias Gram-Positivas/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/microbiologia , Hepatopatias Alcoólicas/etiologia , Hepatopatias Alcoólicas/genética , Hepatopatias Alcoólicas/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Complemento/deficiência , Receptores de Complemento/genética , Receptores de Complemento 3b/genética
3.
Inflamm Allergy Drug Targets ; 14(1): 37-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26434700

RESUMO

CONTEXT: Polygala sabulosa, popularly known as "timutu-pinheirinho," has been used in Brazilian folk medicine for the treatment of bowel and kidney disorders and as an expectorant. OBJECTIVE: Evaluate the anti-inflammatory effects of the crude extract (CE), acetonic fraction (Ac), and the main compound, 7-prenyloxi-6-methoxycoumarin (PC) on a mouse model of carrageenan-induced pleurisy. MATERIALS AND METHODS: A mouse model of carrageenan-induced pleurisy was used to investigate the effects of P. sabulosa CE, Ac and PC on leukocyte migration, exudate formation, activities of myeloperoxidase (MPO), and adenosine-deaminase (ADA), levels of tumor necrosis factor-α (TNF-α), interleukin 1ß (IL-1ß) and nitric oxide (NO). In addition, the effect of the plant material on lung histology was also evaluated. The effects of PC on the TNF-α, IL-1ß and NO synthase 2 (NOS2) mRNA expression, were also investigated. Finally, the effect of PC on the nuclear factor-kappa B (NF-κB) and p38 mitogen-activated protein kinase (p38 MAPK) was also evaluated. RESULTS: CE, Ac and PC reduced inflammation in the pleural cavity and lungs. This effect was evidenced by reduction on all inflammatory parameters evaluated; the exception being the inability of the CE to inhibit exudate formation. In isolation, PC showed reduction on mRNA levels of TNF-α, IL-1ß and NOS2, and on activation of the NF-κB and p38 MAPK pathways. CONCLUSION: The presented results show that P. sabulosa has significant anti-inflammatory activity, as does its main compound, PC. Moreover, the results suggest that PC exerts its effects mainly by inhibited the NF-κB and p38 MAPK pathways.


Assuntos
Anti-Inflamatórios/administração & dosagem , Cumarínicos/administração & dosagem , NF-kappa B/metabolismo , Extratos Vegetais/administração & dosagem , Pleurisia/tratamento farmacológico , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Carragenina/administração & dosagem , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Pleurisia/induzido quimicamente , Pleurisia/imunologia , Polygala/imunologia , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
4.
Braz. j. microbiol ; 42(3): 1065-1075, July-Sept. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-607537

RESUMO

Crude extracts and fractions of five species of Polygala - P. campestris, P. cyparissias, P. paniculata, P. pulchella and P. sabulosa - were investigated for their in vitro antifungal activity against opportunistic Candida species, Cryptococcus gattii and Sporothrix schenckii with bioautographic and microdilution assays. In the bioautographic assays, the major extracts were active against the fungi tested. In the minimal concentration inhibitory (MIC) assay, the hexane extract of P. paniculata and EtOAc fraction of P. sabulosa showed the best antifungal activity, with MIC values of 60 and 30 µg/mL, respectively, against C. tropicalis, C. gattii and S. schenckii. The compounds isolated from P. sabulosa prenyloxycoumarin and 1,2,3,4,5,6-hexanehexol displayed antifungal activity against S. schenckii (with MICs of 125 µg/mL and 250 µg/mL, respectively) and C. gattii (both with MICs of 250 µg/mL). Rutin and aurapten isolated from P. paniculata showed antifungal activity against C. gattii with MIC values of 60 and 250 µg/mL, respectively. In the antifungal screening, few of the isolated compounds showed good antifungal inhibition. The compound á-spinasterol showed broad activity against the species tested, while rutin had the best activity with the lowest MIC values for the microorganisms tested. These two compounds may be chemically modified by the introduction of a substitute group that would alter several physico-chemical properties of the molecule, such as hydrophobicity, electronic density and steric strain.


Assuntos
Técnicas In Vitro , Estruturas Vegetais , Polygala , Polygalaceae/crescimento & desenvolvimento , Rutina/análise , Plantas
5.
Braz J Microbiol ; 42(3): 1065-75, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24031724

RESUMO

Crude extracts and fractions of five species of Polygala - P. campestris, P. cyparissias, P. paniculata, P. pulchella and P. sabulosa - were investigated for their in vitro antifungal activity against opportunistic Candida species, Cryptococcus gattii and Sporothrix schenckii with bioautographic and microdilution assays. In the bioautographic assays, the major extracts were active against the fungi tested. In the minimal concentration inhibitory (MIC) assay, the hexane extract of P. paniculata and EtOAc fraction of P. sabulosa showed the best antifungal activity, with MIC values of 60 and 30 µg/mL, respectively, against C. tropicalis, C. gattii and S. schenckii. The compounds isolated from P. sabulosa prenyloxycoumarin and 1,2,3,4,5,6-hexanehexol displayed antifungal activity against S. schenckii (with MICs of 125 µg/mL and 250 µg/mL, respectively) and C. gattii (both with MICs of 250 µg/mL). Rutin and aurapten isolated from P. paniculata showed antifungal activity against C. gattii with MIC values of 60 and 250 µg/mL, respectively. In the antifungal screening, few of the isolated compounds showed good antifungal inhibition. The compound α-spinasterol showed broad activity against the species tested, while rutin had the best activity with the lowest MIC values for the microorganisms tested. These two compounds may be chemically modified by the introduction of a substitute group that would alter several physico-chemical properties of the molecule, such as hydrophobicity, electronic density and steric strain.

6.
Eur J Pharmacol ; 643(2-3): 232-8, 2010 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-20599906

RESUMO

The relationship between depression and monoaminergic systems has been hypothesized for many years. In this study, we have investigated the possible antidepressant-like effect of scopoletin, a coumarin from Polygala sabulosa in the tail suspension test and forced swimming test. Moreover, the ability of scopoletin to reverse the depression-like behavior in the forced swimming test induced by immobility stress in mice was evaluated. Scopoletin reduced the immobility time in the tail suspension test (10-100mg/kg, p.o.), but not in the forced swimming test. Fluoxetine (positive control) decreased the immobility time in the forced swimming and tail suspension tests (20mg/kg, p.o. and 10mg/kg. p.o., respectively). Immobility stress caused an increase in the immobility time in the forced swimming test (depression-like behavior), which was reversed by scopoletin (1-100mg/kg, p.o.) and fluoxetine (10mg/kg, p.o.). Scopoletin produced no psychostimulant effect in the open-field test. The pretreatment of mice with ketanserin (5mg/kg, i.p., a preferential 5-HT(2A) receptor antagonist), prazosin (1mg/kg, i.p., an alpha(1)-adrenoceptor antagonist), yohimbine (1mg/kg, i.p., an alpha(2)-adrenoceptor antagonist), haloperidol (0.2mg/kg, i.p., a dopaminergic receptor antagonist), SCH23390 (0.05 mg/kg, s.c., a dopamine D(1) receptor antagonist) or sulpiride (50mg/kg, i.p., a dopamine D(2) receptor antagonist), but not WAY100635 (0.1mg/kg, s.c., a selective 5-HT(1A) receptor antagonist) prevented the antidepressant-like effect of scopoletin (10mg/kg, p.o.) in the tail suspension test. The results indicate that its antidepressant-like effect is dependent on the serotonergic (5-HT(2A) receptors), noradrenergic (alpha(1)- and alpha(2)-adrenoceptors) and dopaminergic (dopamine D(1) and D(2) receptors) systems.


Assuntos
Antidepressivos/uso terapêutico , Monoaminas Biogênicas/metabolismo , Cumarínicos/uso terapêutico , Depressão/prevenção & controle , Polygala/química , Receptores de Amina Biogênica/metabolismo , Escopoletina/uso terapêutico , Animais , Antidepressivos/administração & dosagem , Antidepressivos/efeitos adversos , Antidepressivos/isolamento & purificação , Comportamento Animal/efeitos dos fármacos , Monoaminas Biogênicas/antagonistas & inibidores , Cumarínicos/administração & dosagem , Cumarínicos/efeitos adversos , Cumarínicos/isolamento & purificação , Depressão/tratamento farmacológico , Relação Dose-Resposta a Droga , Comportamento Exploratório/efeitos dos fármacos , Feminino , Elevação dos Membros Posteriores , Camundongos , Neurotransmissores/farmacologia , Extratos Vegetais/química , Isoformas de Proteínas/antagonistas & inibidores , Distribuição Aleatória , Receptores de Amina Biogênica/antagonistas & inibidores , Escopoletina/administração & dosagem , Escopoletina/efeitos adversos , Escopoletina/isolamento & purificação , Natação , Fatores de Tempo
7.
Basic Clin Pharmacol Toxicol ; 103(1): 43-7, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18598298

RESUMO

This study investigated the role of the glutamatergic system on the antinociception caused by Polygala sabulosa hydroalcoholic extract (HE). The systems mediated by substance P, capsaicin, interleukin-1beta (IL-1beta) and tumour necrosis factor-alpha (TNF-alpha) were also investigated. P. sabulosa HE given orally produced a significant inhibition of glutamate-induced paw licking [ID(50) = 530.3 (416.7-674.8) mg/kg and inhibition of 79 +/- 6% at 1000 mg/kg]. The plant derivatives alpha-spinasterol, scopoletin and styryl-2-pyrones (compound 1 and 3) (10 mg/kg, intraperitoneally) inhibited 80 +/- 7%, 46 +/- 11%, 45 +/- 11% and 35 +/- 13% the nociceptive response caused by glutamate, respectively. Furthermore, P. sabulosa HE (500 mg/kg, orally) caused marked inhibition of nociceptive response induced by intrathecal injection of glutamate, N-methyl-d-aspartic acid, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, kainate, TNF-alpha and IL-1beta, with inhibitions of 44 +/- 7%, 55 +/- 4%, 38 +/- 10%, 61 +/- 7%, 76 +/- 9% and 100%, respectively. In contrast, P. sabulosa HE (500 mg/kg, orally) did not affect the biting response induced by the metabotropic glutamatergic receptor agonist (+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid, substance P and capsaicin. The locomotor activity was altered only in mice treated with a very high dose (1000 mg/kg) of P. sabulosa HE. Our results showed that the antinociceptive effects of P. sabulosa HE are associated with an inhibition of glutamatergic transmission and an inhibition of pathways dependent on pro-inflammatory cytokines. The plant derivatives alpha-spinasterol, scopoletin and styryl-2-pyrones play an important role on the antinociceptive effects of P. sabulosa HE.


Assuntos
Analgésicos/farmacologia , Citocinas/fisiologia , Dor/tratamento farmacológico , Polygala/química , Receptores de Glutamato/fisiologia , Administração Oral , Analgésicos/uso terapêutico , Animais , Capsaicina/farmacologia , Citocinas/farmacologia , Relação Dose-Resposta a Droga , Agonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Interleucina-1beta/farmacologia , Masculino , Camundongos , Dor/fisiopatologia , Medição da Dor , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Receptores da Neurocinina-1/agonistas , Substância P/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
8.
Rev. bras. farmacogn ; 18(2): 177-182, abr.- jun. 2008. ilus, tab
Artigo em Inglês | LILACS | ID: lil-488650

RESUMO

A bioatividade das frações e compostos obtidos de Polygala sabulosa contra as formas epimastigota, tripomastigota sanguínea e amastigota de Trypanosoma cruzi foram avaliadas in vitro. Frações diclorometano e acetato de etila mostraram potente atividade tripanocida sob as formas epimastigotas (IC50 < 10,4 µg/mL). Análises por cromatografia em camada delgada destas frações confirmaram a presença de compostos previamente descritos (dihidroestiril-2-pironas, estiril-2-pironas e 6-metoxi-7-preniloxicumarina). Após o fracionamento da fração diclorometano por cromatografia em coluna, obteve-se o composto α-espinasterol e da fração acetato de etila obtiveram-se os compostos apigenina, quercetina e uma quercetina-3- O-glicosídeo, todos descritos pela primeira vez para o gênero Polygala. 4-metoxi-6-(11,12-metilenodioxi-14-metoxidihidroestiril)-2-pirona, 4-metoxi-6-(11,12-dimetoxi-14-metoxiestiril)-2-pirona, 6-metoxi-7-preniloxicumarina e quercetina-3- O-glicosídeo mostraram fraca atividade contra a forma tripomastigota sanguínea (IC50 < 1008,6 µg/mL). A cumarina prenilada foi o composto mais ativo contra ambas as formas epimastigota e tripomastigota, com IC50 10,5 e 88,2 µg/mL, respectivamente. A atividade hemolítica e a toxicidade celular de cada composto foram também avaliadas. Além disso, 4-metoxi-6-(11,12-metilenodioxi-14-metoxidihidroestiril)-2-pirona e 6-metoxi-7-preniloxicumarina reduziram em quatro vezes a infecção em ratos por Vero Cells nas concentrações de 100 e 50 µg/mL respectivamente. Esses resultados mostram, pela primeira vez, a atividade de compostos de P. sabulosa contra T. cruzi.


Bioactivity of fractions and compounds obtained from Polygala sabulosa against Trypanosoma cruzi epimastigote, blood trypomastigote and amastigote forms were evaluated in vitro. Dichloromethane and ethyl acetate fractions showed a strong trypanocidal activity on epimastigotes (IC50 < 10.4 µg/mL). Chromatographic analysis by TLC of these fractions confirmed the presence of previously described compounds (dihydrostyryl-2-pyrones, styryl-2-pyrones and 6-methoxy-7-prenyloxycoumarin). The dichloromethane fraction was fractioned by silica gel column chromatography to afford the compound α-spinasterol and the ethyl acetate fraction yielded apigenin, quercetin and a quercetin-3-O-glucoside, being the first description for the Polygala genus. 4-Methoxy-6-(11,12-methylenedioxy-14-methoxydihydrostyryl)-2-pyrone, 4-methoxy-6-(11,12-dimethoxystyryl)-2-pyrone, 6-methoxy-7-prenyloxycoumarin and quercetin-3-O-glucoside showed a weak activity against blood trypomastigotes (IC50 < 1008.6 µg/mL). The prenylated coumarin was the most active compound against both epimastigote and trypomastigote forms, IC50 10.5 and 88.2 µg/mL, respectively. The hemolytic activity and cell toxicity of each active compound was also assessed. Furthermore, 4-methoxy-6-(11,12-methylenedioxy-14-methoxydihydrostyryl)-2-pyrone and 6-methoxy-7-prenyloxycoumarin reduced 4 times the T. cruzi infection rate for Vero cells at 100 and 50 µg/mL, respectively. These results show for the first time active compounds against T. cruzi in P. sabulosa.

9.
Chem Res Toxicol ; 20(12): 1919-26, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17944542

RESUMO

Plants of the genus Polygala have been shown to possess protective effects against neuronal death and cognitive impairments in neurodegenerative disorders related to excitotoxicity. Moreover, previous reports from our group have shown the neuroprotective effects of the plant Polygala paniculata against methylmercury (MeHg)-induced neurotoxicity. In this work, we have examined the potential protective effects of three compounds (7-prenyloxy-6-methoxycoumarin, quercetin, and 1,5-dihidroxi-2,3-dimethoxy xanthone) from Polygala species against MeHg- and mercuric chloride (HgCl2)-induced disruption of mitochondrial function under in vitro conditions using mitochondrial-enriched fractions from mouse brain. MeHg and HgCl2 (10-100 microM) significantly decreased mitochondrial viability; this phenomenon was positively correlated to mercurial-induced glutathione oxidation. Among the isolated compounds, only quercetin (100-300 microM) prevented mercurial-induced disruption of mitochondrial viability. Moreover, quercetin, which did not display any chelating effect on MeHg or HgCl2, prevented mercurial-induced glutathione oxidation. The present results suggest that the protective effects of quercetin against mercurial-induced mitochondrial dysfunction is related to the removal of oxidant species generated in the presence of either MeHg or HgCl2. Reinforcing this hypothesis, MeHg and HgCl2 increased the production of hydrogen peroxide in the brain mitochondria, as well as the levels of malondialdehyde. These oxidative phenomena were prevented by co-incubation with quercetin or catalase. These results are the first to show the involvement of hydrogen peroxide as a crucial molecule related to the toxic effects of both organic and inorganic mercurials in brain mitochondria. In addition, the study is the first to show the protective effect of quercetin against mercurial-induced toxicity, pointing to its capability to counteract mercurial-dependent hydrogen peroxide generation as a potential molecular mechanism of protection. Taken together, these data render quercetin a promising molecule for pharmacological studies with respects to mercurials' poisoning.


Assuntos
Encéfalo/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Cloreto de Mercúrio/toxicidade , Compostos de Metilmercúrio/toxicidade , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Quercetina/farmacologia , Animais , Encéfalo/metabolismo , Glutationa/metabolismo , Técnicas In Vitro , Masculino , Camundongos , Mitocôndrias/metabolismo , Estrutura Molecular , Fármacos Neuroprotetores/isolamento & purificação , Oxirredução , Polygala/química , Quercetina/isolamento & purificação
10.
Rev. bras. farmacogn ; 16(4): 568-575, out.-dez. 2006. tab, ilus
Artigo em Português | LILACS | ID: lil-451538

RESUMO

Os extratos obtidos pela maceração em CHCl3/MeOH (2:1) de 8 amostras de espécies medicinais e 11 amostras comerciais de chás foram analisados por cromatografia em camada delgada (CCD). Glicolipídios foram detectados em todas as amostras, porém com diferenças quali-quantitativas. Para as plantas medicinais, a maior concentração de glicolipídios foi detectada em Lippia alba e Cymbopogon citratus, enquanto em amostras comerciais, o melhor perfil glicolipídico foi encontrado nos extratos de C. citratus e Baccharis trimera.


The extracts obtained by maceration in CHCl3/MeOH (2:1) of 8 medicinal plants and 11 commercial samples (tea bags) were analysed by thin-layer chromatography. Glycolipids were detected in all the samples, with qualitative and quantitative differences. For the medicinal plants, the highest concentrations were detected in Lippia alba and Cymbopogon citratus. For the commercial samples, the best glycolipidic profiles were found in C. citratus and Baccharis trimera extracts.

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