Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Chem Biodivers ; 21(2): e202301522, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38085680

RESUMO

INTRODUCTION: Studies prove that the use of medicinal plants is a custom carried out by man since ancient times, the evolution of the pharmaceutical industry makes more people consume more natural products. Currently, we can observe that mouthwashes containing natural compounds have shown a growth in demand in the markets and in the professional community. OBJECTIVE: The present study aims to carry out the chemical characterization and microbiological potential of Piper mikanianum (Kunth) Steud essential oil (EOPm), providing data that allows the development of a low-cost mouthwash formulation aimed at vulnerable communities. METHODS: The evaluation of the antibacterial activity and modulator of bacterial resistance was performed by the microdilution method to determine the minimum inhibitory concentration (MIC). The chemical components were characterized by gas chromatography coupled to mass spectrometry, identified 28 constituents, in which Safrole Phenylpropanoid is the major compound, representing 72.6 % of the total composition, followed by α-pinene (10.7 %), Limonene (2 %), ß-caryophyllene (2 %), E-nerolidol (1.9 %), spathulenol (1.3 %) and camphene (1.1 %). RESULTS: The EOPm showed a MIC minimum inhibitory concentration≥1024 µg/mL for all bacterial strains used in the tests. When the EOPm modulating activity combined with chlorhexidine, mouthwash, ampicillin, gentamicin and penicillin G was evaluated against bacterial resistance, the oil showed significant synergistic activity, reducing the MIC of the products tested in combination, in percentage between 20.6 % to 98 .4 %. CONCLUSIONS: We recommend the expansion of tests with greater variation of EOPm concentration combinations and the products used in this study, as well as toxicity evaluation and in vivo tests, seeking the development of a possible low-cost mouthwash formulation accessible to the most vulnerable population.


Assuntos
Óleos Voláteis , Piper , Humanos , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Antissépticos Bucais/farmacologia , Piper/química , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana
2.
3 Biotech ; 13(7): 255, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37396469

RESUMO

Essential oils extracted from many plant species have different biological activities, among which microbial activity stands out. Species of the genus Piper have antimicrobial potential against different species of bacteria and fungi. In this sense, the present study aimed to determine the chemical composition of the essential oil from the leaves of Piper gaudichaudianum (EOPG), as well as to investigate their antimicrobial activity and their modulatory effect on the Norfloxacin resistance in the Staphylococcus aureus SA1199B strain overproducer of the NorA efflux pump. Furthermore, their inhibitory activities on the biofilm formation as well as on the cellular differentiation of C. albicans were evaluated. Gas chromatography analysis identified 24 compounds, such as hydrocarbon sesquiterpenes (54.8%) and oxygenated sesquiterpenes (28.5%). To investigate the antimicrobial potential of EOPG against S. aureus, E. coli, and C. albicans, a microdilution assay was performed, and no intrinsic antimicrobial activity was observed. On the other hand, the oil potentiated the activity of Norfloxacin against the SA1199B strain, indicating that EOPG could be used in association with Norfloxacin against S. aureus strains resistant to this antibiotic. EOPG also inhibited S. aureus biofilm formation, as evidenced by the crystal violet assay. In the dimorphism assay, EOPG was able to inhibit the cell differentiation process in C. albicans. Results indicate that EOPG could be used in association with Norfloxacin in the treatment of infections caused by resistant S. aureus strains overproducing the NorA efflux pump. Furthermore, its ability to inhibit the formation of hyphae by C. albicans suggests that EOPG could also be applied in the prevention and/or treatment of fungal infections.

3.
Plants (Basel) ; 12(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37111810

RESUMO

Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus are the primary bacteria that cause clinical infections, such as urinary and intestinal infections, pneumonia, endocarditis, and sepsis. Bacterial resistance is an innate natural occurrence in microorganisms, resulting from mutations or the lateral exchange of genetic material. This serves as evidence for the association between drug consumption and pathogen resistance. Evidence has demonstrated that the association between conventional antibiotics and natural products is a promising pharmacological strategy to overcome resistance mechanisms. Considering the large body of research demonstrating the significant antimicrobial activities of Schinus terebinthifolius Raddi, the present study aimed to evaluate the chemical composition and antibiotic-enhancing effects of Schinus terebinthifolius Raddi essential oil (STEO) against the standard and multidrug-resistant strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The STEO was extracted by hydrodistillation using a Clevenger-type vacuum rotary evaporator. The Minimum Inhibitory Concentration (MIC) of the STEO was assessed by the microdilution method to evaluate the antibacterial activity. The antibiotic-enhancing activity of the essential oil was assessed by determining the MIC of antibiotics in the presence of a sub-inhibitory concentration (MIC/8) of the natural product. The GC-MS analysis revealed alpha-pinene (24.3%), gamma-muurolene (16.6%), and myrcene (13.7%) as major constituents of the STEO. The STEO potentiated the enhanced antibacterial activity of norfloxacin and gentamicin against all the strains and increased the action of penicillin against the Gram-negative strains. Therefore, it is concluded that although the STEO does not exhibit clinically effective antibacterial activity, its association with conventional antibiotics results in enhanced antibiotic activity.

4.
Curr Pharm Des ; 29(5): 323-355, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36515045

RESUMO

Antibiotic resistance can be characterized, in biochemical terms, as an antibiotic's inability to reach its bacterial target at a concentration that was previously effective. Microbial resistance to different agents can be intrinsic or acquired. Intrinsic resistance occurs due to inherent functional or structural characteristics of the bacteria, such as antibiotic-inactivating enzymes, nonspecific efflux pumps, and permeability barriers. On the other hand, bacteria can acquire resistance mechanisms via horizontal gene transfer in mobile genetic elements such as plasmids. Acquired resistance mechanisms include another category of efflux pumps with more specific substrates, which are plasmid-encoded. Efflux pumps are considered one of the main mechanisms of bacterial resistance to antibiotics and biocides, presenting themselves as integral membrane transporters. They are essential in both bacterial physiology and defense and are responsible for exporting structurally diverse substrates, falling into the following main families: ATP-binding cassette (ABC), multidrug and toxic compound extrusion (MATE), major facilitator superfamily (MFS), small multidrug resistance (SMR) and resistance-nodulation-cell division (RND). The Efflux pumps NorA and Tet(K) of the MFS family, MepA of the MATE family, and MsrA of the ABC family are some examples of specific efflux pumps that act in the extrusion of antibiotics. In this review, we address bacterial efflux pump inhibitors (EPIs), including 1,8-naphthyridine sulfonamide derivatives, given the pre-existing knowledge about the chemical characteristics that favor their biological activity. The modification and emergence of resistance to new EPIs justify further research on this theme, aiming to develop efficient compounds for clinical use.


Assuntos
Proteínas de Bactérias , Staphylococcus aureus , Humanos , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Sulfonamidas/farmacologia , Bactérias , Antibacterianos/farmacologia , Sulfanilamida/farmacologia , Naftiridinas/farmacologia , Testes de Sensibilidade Microbiana
5.
Molecules ; 27(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36144647

RESUMO

Commercialized mouthwashes are generally expensive for the most financially vulnerable populations. Thus, several studies evaluate the antimicrobial potential of herbal products, such as essential oils, to reduce the activity of microorganisms in the mouth. The objective of this research was to carry out the chemical characterization and antibacterial activity of the essential oil of Piper mosenii (EOPm), providing data that enable the development of a low-cost mouthwash formulation aimed at vulnerable communities. The analysis of the antibacterial potential and modulator of bacterial resistance was verified by the microdilution method to determine the minimum inhibitory concentration-MIC. The chemical components were characterized by gas chromatography coupled to mass spectrometry, where 23 chemical constituents were detected, with α-pinene, being the major compound. The EOPm showed a MIC ≥ 1024 µg/mL for all bacterial strains used in the tests. When the EOPm modulating activity was evaluated together with chlorhexidine, mouthwash and antibiotics against bacterial resistance, the oil showed a significant synergistic effect, reducing the MIC of the products tested in combination, in percentages between 20.6% to 96.3%. Therefore, it is recommended to expand the tests with greater variation of EOPm concentration and the products used in this research, in addition to the evaluation of toxicity and in vivo tests, seeking the development of a possible formulation of mouthwash accessible to the vulnerable population.


Assuntos
Anti-Infecciosos , Óleos Voláteis , Piper , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Clorexidina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Testes de Sensibilidade Microbiana , Antissépticos Bucais , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Piper/química
6.
Arch Microbiol ; 203(7): 4727-4736, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34052872

RESUMO

Infectious diseases caused by multidrug-resistant microorganisms has increased in the last years. Piper species have been reported as a natural source of phytochemicals that can help in combating fungal and bacterial infections. This study had as objectives characterize the chemical composition of the essential oil from Piper caldense (EOPC), evaluate its potential antimicrobial activity, and investigate the synergistic effect with Norfloxacin against multidrug-resistant S. aureus overproducing efflux pumps, as well as, verify the EOPC ability to inhibit the Candida albicans filamentation. EOPC was extracted by hydrodistillation, and the chemical constituents were identified by gas chromatography, allowing the identification of 24 compounds (91.9%) classified as hydrocarbon sesquiterpenes (49.6%) and oxygenated sesquiterpenes (39.5%). Antimicrobial tests were performed using a 96-well plate microdilution method against C. albicans ATCC 10231, Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923 standard strains, as well as against multidrug-resistant strains S. aureus SA1199B (overexpressing norA gene), S. aureus K2068 (overexpressing mepA gene) and S. aureus K4100 (overexpressing qacC gene). The oil showed activity against C. albicans ATCC 10231 (≥ 512 µg/mL) and was able to inhibit hyphae formation, an important mechanism of virulence of C. albicans. On the other hand, EOPC was inactive against all bacterial strains tested (≤ 1,024 µg mL). However, when combined with Norfloxacin at subinhibitory concentration EOPC reduced the Norfloxacin and Ethidium bromide MIC values against S. aureus strains SA1199B, K2068 and K4100. These results indicate that EOPC is a source of phytochemicals acting as NorA, MepA and QacC inhibitors.


Assuntos
Proteínas de Bactérias , Staphylococcus aureus Resistente à Meticilina , Norfloxacino , Óleos Voláteis , Piper , Staphylococcus aureus , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Testes de Sensibilidade Microbiana , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Norfloxacino/química , Norfloxacino/farmacologia , Óleos Voláteis/farmacologia , Piper/química , Piper/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética
7.
Arch Microbiol ; 203(6): 3077-3087, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33787988

RESUMO

This study aimed to investigate the chemical composition and antifungal potential of the essential oil of Baccharis trimera (Less.) DC. against Candida strains. The half maximal inhibitory concentration (IC50) was assessed by the microdilution method using the essential oil at a concentration range of 8192 to 8 µg/mL. The minimum fungicide concentration (MFC) was determined by subculture in solid medium. The ability of the essential oil to modulate the activity of antifungals was determined in wells treated simultaneously with the oil at a subinhibitory concentration (MFC/16) and fluconazole (FCZ). The fungal morphology was analyzed by microscopy. Gas chromatography coupled with mass spectrometry (GC/MS) was used to identify the chemical composition. The essential oil presented an CI50 of 11.24 and 1.45 µg/mL, which was found to potentiate the effect of FCZ against Candida albicans. On the other hand, this combined treatment resulted in antagonism against Candida tropicalis and no evident modulation against Candida krusei was observed. The essential oil significantly inhibited hyphae growth. However, with a MFC ≥ 16,384 µg/mL, it is assumed that it has a fungistatic action. The antifungal properties demonstrated in this study might be related to the presence of sesquiterpenes and monoterpenes, and the interaction between them. In conclusion, Baccharis trimera showed promising anti-Candida effects, in addition to potentiating the activity of FCZ against Candida albicans, affecting its morphological transition. Therefore, this species constitutes a source of chemical compounds with the potential to be used in the combat of fungal infections.


Assuntos
Baccharis , Candida , Óleos Voláteis , Antifúngicos/farmacologia , Baccharis/química , Candida/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/farmacologia , Pichia/efeitos dos fármacos
8.
Eur J Pharm Sci ; 160: 105753, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33581258

RESUMO

This study aimed to evaluate the antibacterial activity and to verify, in silico and in vitro, the inhibition of efflux mechanisms using a series of synthesized 1,8-naphthyridines sulfonamides against Staphylococcus aureus strains carrying MepA efflux pumps. The chemical synthesis occurred through the thermolysis of the Meldrum's acid adduct. The sulfonamide derivatives were obtained by the sulfonylation of 2-amino-5­chloro-1,8-naphthyridine with commercial benzenesulfonyl chloride. Antibacterial activity was assessed by the broth microdilution test. Efflux pump inhibitory capacity was evaluated in silico by molecular docking and in vitro by analyzing synergistic effects on ciprofloxacin and ethidium bromide (EtBr) and by EtBr fluorescence emission assays. The following 1,8-naphthyridines were synthesized: 4-methyl-N-(5­chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide (Compound 10a); 2,5-dichloro-N-(5­chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide (Compound 10b); 4-fluoro-N-(5­chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide (Compound 10c); 2,3,4-trifluoro-N-(5­chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide (Compound 10d); 3-trifluoromethyl-N-(5­chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide (Compound 10e); 4­bromo-2,5-difluoro-N-(5­chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide (Compound 10f). The 1,8-naphthyridines derivatives associated with sulfonamides did not show antibacterial activity. However, they showed a favorable pharmacokinetic profile with possible MepA efflux pump inhibitory action, demonstrated in molecular docking. In addition to the promising results in reducing the concentration of intracellular EtBr. 1,8-naphthyridines act as putative agents in the inhibitory action of the MepA efflux pump.


Assuntos
Proteínas Associadas à Resistência a Múltiplos Medicamentos , Naftiridinas , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Naftiridinas/farmacologia , Sulfonamidas/farmacologia
9.
Microb Pathog ; 147: 104268, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32574783

RESUMO

Naphthyridines represent a class of heterocyclic compounds formed by two condensed aromatic rings. This study aimed to evaluate the antibacterial activity and in vitro inhibition of efflux resistance mechanisms of a series of 1,8-naphthyridine sulfonamides against strains carrying Tet(K) and MsrA efflux pumps. The efflux pump inhibitory capacity was evaluated by analyzing synergistic effects between 1,8-naphthyridine sulfonamides and standard antibiotics, as well as ethidium bromide. The following 1,8-naphthyridines were used: 4-methyl-N-(5-chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide (Naph 1); 2,5-Dichloro-N-(5-chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide (Naph 2); 2,3,4-trifluoro-N-(5-chloro-1,8-naphthyridin-2-yl)benzenesulfonamide (Naph 7); 3-trifluoromethyl-N-(5-chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide (Naph 9). The 1,8-naphthyridine sulfonamide derivatives possessed a potential Tet(K) and MsrA efflux pump inhibitory action.


Assuntos
Antibacterianos , Staphylococcus aureus , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Etídio , Testes de Sensibilidade Microbiana , Naftiridinas/farmacologia , Sulfonamidas/farmacologia
10.
Microb Pathog ; 145: 104223, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32376358

RESUMO

Essential oils are secondary metabolites with immense pharmacological potential.These substances are abundantly produced by plants of the family Asteraceae, such as Baccharis coridifolia. Previous studies have demonstrated that this species has pharmacological properties that make it a promising source of new antibacterial agents. Therefore, the present study aimed to evaluate the antibacterial and antibiotic-modulating activity of Baccharis coridifolia essential oil against multidrug-resistant (MDR) strains. The phytochemical analysis was carried out by gas chromatography coupled to Mass Spectroscopy (GC/MS), and realized the Minimum Inhibitory Concentation (MIC) and antibiotic-modulation from the microdilution method in 96-well plates. It was revealed the presence of germacrene D (23.7%), bicyclogermacrene (17.1%), and (E)-caryophyllene (8.4%) as major components. The minimum inhibitory concentration of essential oil against strains of Pseudomonas aeruginosa (512 µg/mL) and Staphylococcus aureus (128 µg/mL) demonstrated clinically relevant antibacterial activity. In addition, the combination of subinhibitory doses of the oil with conventional antibiotics showed synergism, indicating potentiation of the antibacterial effect. In conclusion, the essential oil of Baccharis coridifolia (EOBc) presented antibacterial and antibiotic-modulating activities that place this species as a source of molecules useful in the fight against bacterial resistance.


Assuntos
Baccharis , Óleos Voláteis , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Folhas de Planta
11.
Food Chem Toxicol ; 135: 110987, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31759067

RESUMO

The Piper mikanianum species were investigated by the antimicrobial potential and chemical composition. Chemical analysis was performed by gas chromatography coupled to mass spectrometry (GC/MS). The Minimum Inhibitory Concentration (MIC) as well as the 50% Inhibitory Concentration against Candida strains were determined by microdilution. The effect of the drug-oil combination was also evaluated to verify possible synergism. The Minimum Fungicidal Concentration (MFC) was evaluated by subculturing the microdilution in Petri dishes and the anti-pleomorphism potential of the oil was tested in humid chambers. Chemical analysis revealed safrol as the major compound. The results from the intrinsic activity evaluation of the oil did not reveal a clinical importance, however, it presented a synergistic effect when associated with gentamicin against the multidrug resistant E. coli strain and when associated with fluconazole against fungal strains. Moreover, the oil possessed a fungistatic effect. Total inhibition of filamentous structures occurred in both Candida species in the anti-virulence test. The P. mikanianum essential oil showed a potentiating activity of drugs for which resistance exists and an inhibitory effect of one of the main virulence factors of the Candida genus, morphological transition, which has been previously shown to be responsible for causing invasive infections in human tissues.


Assuntos
Anti-Infecciosos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos Voláteis/farmacologia , Piper/química , Candida/classificação , Candida/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Especificidade da Espécie , Staphylococcus aureus/efeitos dos fármacos
12.
Microb Pathog ; 136: 103700, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31472258

RESUMO

The secular use of plants in popular medicine has emerged as a source for the discovery of new compounds capable of curing infections. Among microbial resistance to commercial drugs, species such as Piper diospyrifolium Kunth, which are used in popular therapy, are targets for pharmacological studies. With this in mind, antimicrobial experiments with the essential oil from the P. diospyrifolium (PDEO) species were performed and its constituents were elucidated. The oil compounds were identified by gas chromatography coupled to mass spectrometry (GC/MS). The broth microdilution method with colorimetric readings for bacterial tests (Escherichia coli and Staphylococcus aureus) and spectrophotometric readings for fungal tests (Candida albicans and Candida tropicalis), whose data were used to create a cell viability curve and calculate its IC50 against fungal cells, were used to determine the minimum inhibitory concentration of the oil and its combined action with commercial drugs. The oil's minimal fungicidal concentration and its action over fungal morphological transition were analyzed by subculture and microculture, respectively. Chemical analysis revealed Z-Carpacin, Pogostol and E-Caryophyllene as the most abundant compounds. Results from the intrinsic analysis were considered clinically irrelevant, however the oil presented a synergistic effect against multiresistant E. coli and S. aureus strains when associated with gentamicin, and against the standard and isolated C. tropicalis strains with fluconazole. A fungicidal effect was observed against the C. albicans isolate. Candida spp. hyphae inhibition was verified for all strains at the highest tested concentrations. The P. diospyrifolium essential oil presented a promising effect when associated with commercial drugs and against a fungal virulence factor. Thus, the oil presented active compounds which may help the development of new drugs, however, new studies are needed in order to clarify the oil's mechanism of action, as well as to identify its active constituents.


Assuntos
Anti-Infecciosos/análise , Candida/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Óleos Voláteis/química , Compostos Fitoquímicos/análise , Piper/química , Staphylococcus aureus/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/farmacologia
13.
Front Plant Sci ; 10: 834, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31338098

RESUMO

Arctium species are known for a variety of pharmacological effects due to their diverse volatile and non-volatile secondary metabolites. Representatives of Arctium species contain non-volatile compounds including lignans, fatty acids, acetylenic compounds, phytosterols, polysaccharides, caffeoylquinic acid derivatives, flavonoids, terpenes/terpenoids and volatile compounds such as hydrocarbons, aldehydes, methoxypyrazines, carboxylic and fatty acids, monoterpenes and sesquiterpenes. Arctium species also possess bioactive properties such as anti-cancer, anti-diabetic, anti-oxidant, hepatoprotective, gastroprotective, antibacterial, antiviral, antimicrobial, anti-allergic, and anti-inflammatory effects. This review aims to provide a complete overview of the chemistry and biological activities of the secondary metabolites found in therapeutically used Arctium species. Summary of pharmacopeias and monographs contents indicating the relevant phytochemicals and therapeutic effects are also discussed, along with possible safety considerations.

14.
J Intercult Ethnopharmacol ; 4(1): 57-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26401386

RESUMO

AIM: The present study was undertaken to evaluate the acute and subchronic antihyperglycemic effects of methanolic extract of Bowdichia virgilioides root bark of B. virgilioides in streptozotocin (STZ)-induced diabetic rats. MATERIALS AND METHODS: The extract (100, 250 or 500 mg/kg) was orally administered to male Wistar diabetic (STZ, 42 mg/kg i.v.) and non-diabetic rats into two main protocols: (i) subchronic experiments, where animals were treated for 21 days with B. virgilioides extract and the following parameters were evaluated: Body weight, fluid and food intake (determined daily), urinary glucose and urea (every 3 days) and glycemia (every 5 days). At the end of the experimental period, skeletal muscles (extensor digitorum longus [EDL] and soleus), retroperitoneal and epididymal white adipose tissues were collected and weighed; liver samples were used for the determination of the lipid and glycogen contents; (ii) acute experiments, which evaluated the alterations on fasting and post-prandial glycemia and on glucose tolerance using the oral glucose tolerance test (OGTT). RESULTS: In subchronic experiments, the treatment with B. virgilioides extract did not change any parameter evaluated in diabetic and non-diabetic animals. On fasting and post-prandial glycemia, the extract treatment did not promote changes in the glycemia values in diabetic or non-diabetic animals. In OGTT, the treatment with 500 mg/kg B. virgilioides extract reduced the hyperglycemia peak after a glucose overload, when compared with non-treated diabetic animals, resulting in a lower area under curve. CONCLUSION: The results of our work indicate that B. virgilioides root extract promotes an acute antihyperglycemic effect in STZ-diabetic rats; this effect probably occurs through an inhibition of the intestinal glucose absorption. The continuity of the research is necessary to elucidate these possibilities.

15.
Parasitology ; 138(10): 1224-33, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21810308

RESUMO

Leishmaniasis is one of the neglected diseases. High cost, systemic toxicity, and diminished efficacy due to development of resistance by the parasites has a negative impact on the current treatment options. Thus, the search for a new, effective and safer anti-leishmanial drug becomes of paramount importance. Compounds derived from natural products may be a better and cheaper source in this regard. This study evaluated the in vitro anti-leishmanial activity of Spiranthera odoratíssima (Rutaceae) fractions and isolated compounds, using promastigote and amastigote forms of different Leishmania species. J774 A.1 macrophage was used as the parasite host cell for the in vitro assays. Evaluations of cytoxicity, nitric oxide (NO), interleukin-10 and in silico analysis were carried out. In vitro experiments showed that the fruit hexanic fraction (Fhf) and its alkaloid skimmianine (Skm) have a significant (P<0·001) effect against L. braziliensis. This anti-L. braziliensis activity of Fhf and Skm was due to increased production of NO and attenuation of IL-10 production in the macrophages at concentrations ranging from 1·6 to 40·0 µg/ml. The in silico assay demonstrated significant interaction between Skm and amino acid residues of NOS2. Skm is thus a promising drug candidate for L. braziliensis due to its potent immunomodulatory activity.


Assuntos
Antiprotozoários/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Estágios do Ciclo de Vida/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Quinolinas/farmacologia , Rutaceae/química , Alcaloides/química , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Animais , Antiprotozoários/química , Antiprotozoários/uso terapêutico , Células Cultivadas , Frutas/química , Hexanos/química , Humanos , Concentração Inibidora 50 , Interleucina-10/antagonistas & inibidores , Interleucina-10/biossíntese , Leishmania braziliensis/citologia , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania braziliensis/metabolismo , Leishmaniose Cutânea/parasitologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Camundongos , Modelos Moleculares , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/química , Óxido Nítrico Sintase Tipo II/metabolismo , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Quinolinas/química , Quinolinas/uso terapêutico
16.
Bioorg Med Chem ; 15(24): 7553-60, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17889546

RESUMO

In the present paper 12 N-quinolin-8-yl-arylsulfonamides synthesized by coupling 8-aminoquinolines with various arylsulfonylchlorides were assayed in vitro against Leishmania amazonensis, Leishmania chagasi and Trypanosoma cruzi strains. This series of new compounds were found to be selective for Leishmania spp. promastigote and amastigote forms. The most active compound was the N-(8-quinolyl)-3,5-difluoro-benzenesulfonamide 10 with an IC(50) against L. amazonensis and L. chagasi of 2.12 and 0.45 microM, respectively. The less cytotoxic biphenyl derivative 7 was very effective against intracellular L. amazonensis with a reduction of macrophage cell infection of 82.1% at 25 microM. In addition, a copper complex 17 of an inactive ligand was readily synthesized and showed high leishmanicidal and trypanocidal activity against both extra and intracellular forms.


Assuntos
Leishmania/efeitos dos fármacos , Quinolinas , Sulfonamidas , Tripanossomicidas/síntese química , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antiprotozoários/síntese química , Antiprotozoários/química , Antiprotozoários/farmacologia , Cobre/química , Concentração Inibidora 50 , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Testes de Sensibilidade Parasitária , Quinolinas/síntese química , Quinolinas/química , Quinolinas/farmacologia , Sulfonamidas/síntese química , Sulfonamidas/química , Sulfonamidas/farmacologia , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Zinco/química
17.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): m22-3, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21200567

RESUMO

In the title compound, [Zn(C(17)H(14)Cl(2)N(3)O(3)S)(2)(H(2)O)(2)], the Zn(II) ion has a tetra-hedral coordination formed by the two N atoms of the sulfonamide groups and the two water mol-ecules. Two inter- and two intra-molecular O-H⋯O hydrogen bonds are observed in the crystal structure.

18.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o52, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21200928

RESUMO

In the title compound, C(18)H(19)N(3)O(3)S, the phenyl ring and the pyrazole ring are twisted with respect to each other by an angle of 49.11 (7)°. The C-N-S-C torsion angle is -122.5 (2)°. The methyl group bonded to the N atom of the pyrazole ring has a large deviation from the mean ring plane of 0.603 (3) Å. One inter-molecular N-H⋯O and two non-classical inter-molecular C-H⋯O hydrogen bonds are observed in the crystal structure.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA