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1.
Lett Appl Microbiol ; 72(3): 292-298, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32790923

RESUMO

Dermatophytoses are infections that affect keratinized tissues. Their main etiologic agents are fungi of the genera Microsporum and Trichophyton. The emergence of resistant fungi and the clinical relevance of dermatophytosis have encouraged studies that aim to increase the arsenal of drugs or act on mechanisms that confer multiple drug resistance. This study investigated the modulating activity of terbinafine promoted by dihydrojasmone and terpinolene against Microsporum canis LM 216, Trichophyton interdigitale H6 and T. interdigitale Δmdr2. The minimum inhibitory concentration (MIC) of test drugs was determined by broth microdilution. The effect of the drugs tested on plasma membrane functionality was analysed. Terbinafine MIC was determined in sub-inhibitory concentrations of monoterpenes. Finally, it was performed an association study with terbinafine and monoterpenes. Dihydrojasmone presented lower MIC values than terpinolene. All fungi were sensitive to terbinafine, starting at 1 µg ml-1 . All tested drugs increased K+ release (P < 0·05), affecting the functionality of the plasma membrane. Dihydrojasmone modulated the sensitivity of all strains against terbinafine, and terpinolene modulated the sensitivity of M. canis LM 216 and T. interdigitale Δmdr2. The monoterpenes and terbinafine drug associations presented synergism. In conclusion, the results suggest that the dihydrojasmone and terpinolene are promising antifungal agents that potentiate the antifungal activity of terbinafine against dermatophytes.


Assuntos
Antifúngicos/farmacologia , Arthrodermataceae/efeitos dos fármacos , Monoterpenos Cicloexânicos/farmacologia , Dermatomicoses/tratamento farmacológico , Microsporum/efeitos dos fármacos , Terbinafina/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Monoterpenos/farmacologia
2.
Toxicol In Vitro ; 26(4): 585-94, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22386657

RESUMO

In this study, the cytotoxicity, genotoxicity and early ROS generation of 2,2-dimethyl-(3H)-3-(N-3'-nitrophenylamino)naphtho[1,2-b]furan-4,5-dione (QPhNO(2)) were investigated and compared with those of its precursor, nor-beta-lapachone (nor-beta), with the main goal of proposing a mechanism of antitumor action. The results were correlated with those obtained from electrochemical experiments held in protic (acetate buffer pH 4.5) and aprotic (DMF/TBABF(4)) media in the presence and absence of oxygen and with those from dsDNA biosensors and ssDNA in solution, which provided evidence of a positive interaction with DNA in the case of QPhNO(2). QPhNO(2) caused DNA fragmentation and mitochondrial depolarization and induced apoptosis/necrosis in HL-60 cells. Pre-treatment with N-acetyl-l-cysteine partially abolished the observed effects related to the QPhNO(2) treatment, including those involving apoptosis induction, indicating a partially redox-dependent mechanism. These findings point to the potential use of the combination of pharmacology and electrochemistry in medicinal chemistry.


Assuntos
Antineoplásicos/farmacologia , Benzofuranos/farmacologia , Naftoquinonas/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA , Células HL-60 , Humanos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
3.
Parasitology ; 139(1): 26-36, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21939585

RESUMO

Chagas' disease, caused by the protozoan Trypanosoma cruzi, represents a serious health problem in Latin America, and the available chemotherapy, which is based on 2 nitro-derivatives, is not satisfactory. In folk medicine, natural products including naphthoquinones have been employed for the treatment of different parasitic diseases. In the pursuit of alternative drugs for Chagas' disease, we investigated the mechanism of action of the triazolic naphthoquinone (TN; 2,2-dimethyl-3-(4-phenyl-1H-1,2,3-triazol-1-yl)-2,3-dihydronaphtho[1,2-b]furan-4,5-dione), which is the most active compound against T. cruzi trypomastigotes among a series of naphthofuranquinones. TN was active against the 3 parasite forms producing a dose-dependent inhibitory effect. In epimastigotes, TN induced reservosome disruption, flagellar blebbing, Golgi disorganization, the presence of cytosolic concentric membrane structures and abnormal multiflagellar parasites. The treatment also led to the appearance of well-developed endoplasmic reticulum profiles surrounding organelles that associated with an increase in monodansylcadaverine labelling, suggesting autophagy as part of the TN mechanism of action. Interestingly, no ultrastructural damage was detected in the mitochondria of naphthoquinone-treated epimastigotes. Flow cytometric analysis demonstrated an impairment of mitosis, an increase in ROS production and the maintenance of mitochondrial membrane potential. TN could be a good starting point in the investigation of a chemotherapeutic approach for the treatment of Chagas' disease.


Assuntos
Naftoquinonas/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Autofagia/efeitos dos fármacos , Citometria de Fluxo , Concentração Inibidora 50 , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mitose/efeitos dos fármacos , Organelas/efeitos dos fármacos
4.
Artigo em Espanhol | LILACS | ID: lil-592011

RESUMO

La periodontitis apical asintomática (PAa) es una patología infecciosa caracterizada por destrucción ósea perirradicular asociada a un proceso inflamatorio crónico y producción de mediadores inflamatorios, entre los cuales se encuentran las metaloproteinasas de matriz extracelular (MMPs). Entre éstas, las MMPs-13, -14, -2 y -9, son producidas por el tejido óseo y degradan sinérgicamente el colágeno tipo I, principal componente de los tejidos periodontales, y gelatina, producto de la degradación y desnaturación del colágeno. El objetivo de este estudio fue determinar el patrón de expresión de las MMPs-2, -9, -13 y -14 en granulomas periapicales (GPAs), quistes radiculares inflamatorios (QRIs) y ligamento periodontal sano (LS). Materiales y Métodos: Se seleccionaron 12 pacientes con diagnóstico clínico de PAa e indicación de exodoncia a partir de los cuales se obtuvieron biopsias de lesiones periapicales (LPAs). Como controles, se seleccionaron 7 individuos con indicación de exodoncia de premolares por ortodoncia, obteniéndose biopsias de LS. Se efectuó el diagnóstico anátomo-patológico de los especímenes y se caracterizó la expresión de las MMPs en estudio mediante inmunohistoquímica. Resultados: Las MMPs en estudio sólo se detectaron en GPAs y QRIs, y se inmunolocalizaron principalmente en el infiltrado inflamatorio de éstos. Adicionalmente, la MMP-2 se identificó en fibroblastos del tejido conectivo. Conclusiones: MMPs-2, -9, -13 y -14 se expresan predominantemente en el infiltrado inflamatorio de las LPAs y no en LS, y por tanto se sugiere la participación de estos mediadores en la patogénesis de la PAa.


Asymptomatic apical periodontitis (aAP) is an infectious disease characterized by perirradicular bone destruction associated with chronic inflammation and release of inflammatory mediators, such as matrix metalloproteinases (MMPs). MMPs-13, -14 and -2, -9 are bone-expressed enzymes that can synergistically degrade collagen I, the main component of periodontal extracellular matrix, and gelatin, the product of degradation and denaturation of collagen. The aim of this study was to characterize the expression pattern of MMPs-2, -9, -13, and -14 in periapical granulomas (PGs), radicular cysts (RCs) and healthy periodontal ligament (PDL). Materials and Methods: Individuals with clinical diagnosis of aAP and indication of extraction were selected (N=12), and biopsies of periapical lesions (PLs) were obtained. For controls, 7 subjects with indication of premolar extraction for orthodontic reasons were selected, and PDL biopsies were obtained. Samples were diagnosed by anatomopathological examination and immunohistochemical staining was carried out to characterize MMPs expression. Results: MMPs-2, -9, -13 and -14 detection was limited to PLs and were localized mainly to inflammatory infiltrate on both, PGs and RCs. Additionally, MMP-2 was immunolocalized to fibroblasts from the connective tissue. Conclusions: Whereas MMPs-2, -9, -13 and -14 were not detected in healthy periodontal ligament, they were highly expressed on inflammatory infiltrate from PGs and RCs, suggesting a role of these mediators in aAP pathogenesis.


Assuntos
Humanos , Masculino , Feminino , Adulto , Metaloproteinases da Matriz/análise , Periodontite Periapical/enzimologia , Tecido Periapical/patologia , Estudos Transversais , Imuno-Histoquímica , Matriz Extracelular/enzimologia , /análise , Metaloproteinase 9 da Matriz/análise , /análise , /análise , Tecido Periapical/enzimologia
5.
Artigo em Espanhol | LILACS | ID: lil-582936

RESUMO

El carcinoma verrucoso (CV) es una variante rara del carcinoma de células escamosas con características morfológicas y comportamiento específico. El presente estudio relata el caso de una paciente de género femenino, de 68 años de edad, que presenta un carcinoma verrucoso en lengua, indoloro y con 8 meses de evolución. Además, se realizó una breve revisión de casos clínicos del Instituto de Referencia en Patología Oral (IREPO) de la Facultad de Odontología de la Universidad de Chile, diagnosticados entre enero de 1984 y octubre de 2010, encontrándose 20 casos, con un promedio de edad de 70 años, localizados con mayor frecuencia en encía inferior y lengua.


Verrucous carcinoma (VC), a rare variant of squamous cell carcinoma is an established entity with distinctive morphology and specific clinical behavior. The present study describe a case report of a 68-year-old women who presented a tongue verrucous carcinoma, asymptomatic, that had about 8 months of evolution. A brief review of VC cases diagnosed in Oral Pathology Referral Institute (IREPO), Faculty of Odontology, University of Chile, between 1984 and 2010. It was found 20 cases of verrucous carcinoma with a median age of70-years-old, the most common places were lower gingiva and tongue.


Assuntos
Humanos , Feminino , Idoso , Carcinoma Verrucoso/diagnóstico , Carcinoma Verrucoso/patologia , Neoplasias da Língua/diagnóstico , Neoplasias da Língua/patologia , Carcinoma Verrucoso/cirurgia , Diagnóstico Diferencial , Neoplasias da Língua/cirurgia
6.
Parasitology ; 136(5): 499-510, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19281638

RESUMO

SUMMARY: In a screening of 65 derivatives of natural quinones using bloodstream trypomastigotes of Trypanosoma cruzi, the 3 naphthoimidazoles derived from beta-lapachone - N1, N2 and N3--were selected as the most active. Investigation of their mode of action led to the characterization of mitochondrion, reservosomes and DNA as their main targets, and stimulated further studies on death pathways. Ultrastructural analysis revealed both autophagic (autophagosomes) and apoptotic-like (membrane blebbing) phenotypes. Flow cytometry analysis showed, in N2-treated trypomastigotes, a small increase of phosphatidylserine exposure, and a large increase in the percentage of necrosis, caused by N1 or N2. These death phenotypes were not detected in treated epimastigotes. The strong increase in labelling of monodansyl cadaverine, the inhibition of the death process by wortmannin or 3-methyladenine, the overexpression of ATG genes in treated epimastigotes, together with ultrastructural evidence point to autophagy as the predominant phenotype induced by the naphthoimidazoles. However, there are other pathways occurring concomitantly with variable intensities, justifying the need to detail the molecular features involved.


Assuntos
Autofagia/efeitos dos fármacos , Imidazóis/farmacologia , Naftoquinonas/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Citometria de Fluxo , Imidazóis/síntese química , Imidazóis/química , Microscopia Eletrônica , Naftoquinonas/síntese química , Naftoquinonas/química , Testes de Sensibilidade Parasitária , Fenótipo , Tripanossomicidas/síntese química , Tripanossomicidas/química , Trypanosoma cruzi/genética , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/ultraestrutura
7.
Parasitol Res ; 101(4): 895-905, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17546464

RESUMO

Three naphthoimidazoles presenting aromatic groups attached to the imidazole ring were the most active against trypomastigotes of Trypanosoma cruzi between 45 derivatives from beta-lapachone. N1 is active against the three forms of the parasite. In this work, we investigated N2 and N3 and analyzed the effect of the three derivatives on metacyclogenesis, endocytosis, and cell cycle. In epimastigotes, N2 and N3 blocked the cell cycle, inhibited succinate cytochrome c reductase, metacyclogenesis, and induced damage to mitochondrion, Golgi, and reservosomes. In treated trypomastigotes, there were alterations in the mitochondrion, nucleus and kinetoplast, and DNA fragmentation. Preincubation with cysteine protease inhibitors reversed the effect of N1, N2, and N3. Such reversion and ultrastructural alterations suggest the involvement of autophagy in parasite death. Ultrastructural, flow cytometry, and biochemical studies suggest that naphthoimidazoles interferes with the energetic metabolism and induces DNA fragmentation.


Assuntos
Antiprotozoários/farmacologia , Bignoniaceae/química , Fragmentação do DNA/efeitos dos fármacos , Imidazóis/farmacologia , Mitocôndrias/efeitos dos fármacos , Naftoquinonas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antiprotozoários/síntese química , Antiprotozoários/química , Ciclo Celular/efeitos dos fármacos , DNA Mitocondrial/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Imidazóis/síntese química , Imidazóis/química , Concentração Inibidora 50 , Camundongos , Microscopia Eletrônica de Varredura , Naftoquinonas/síntese química , Naftoquinonas/química , Testes de Sensibilidade Parasitária , Trypanosoma cruzi/citologia , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/ultraestrutura
8.
Int J Antimicrob Agents ; 21(3): 279-84, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12636992

RESUMO

Fourteen extracts from Brazilian traditional medicinal plants used to treat infectious diseases were used to look for potential antimicrobial activity against multiresistant bacteria of medical importance. Staphylococcus aureus strains were susceptible to extracts of Punica granatum and Tabebuia avellanedae. The minimum inhibitory concentrations (MICs) of the total extracts and of additional fractions of these plants were determined by employing strains of methicillin-resistant (MRSA) and -sensitive (MSSA) S. aureus, including isolates of the PFGE clone A, which is prevalent in Brazil and two ATCC reference strains. A mixture of ellagitannins isolated from P. granatum and two naphthoquinones isolated from T. avellanedae demonstrated antibacterial activity against all S. aureus strains tested. Semi-synthetic furanonaphthoquinones (FNQs) showed lower MICs than those exhibited by natural occurring naphthoquinones. The results indicate that these natural products can be effective potential candidates for the development of new strategies to treat MRSA infections.


Assuntos
Taninos Hidrolisáveis , Naftoquinonas/farmacologia , Plantas Medicinais , Staphylococcus aureus/efeitos dos fármacos , Brasil , Humanos , Técnicas In Vitro , Lythraceae , Resistência a Meticilina , Testes de Sensibilidade Microbiana , Naftoquinonas/administração & dosagem , Naftoquinonas/química , Naftoquinonas/isolamento & purificação , Fitoterapia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Tabebuia , Taninos/administração & dosagem , Taninos/química , Taninos/isolamento & purificação , Taninos/farmacologia
9.
Int J Parasitol ; 30(11): 1199-202, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11027788

RESUMO

In the search for new molluscicidal agents we tested the activity of lapachol and other 2-hydroxy-3-alkylnaphthoquinones possessing nitrogenated alkyl chains, against the snail Biomphalaria glabrata. Lapachol, isolapachol and nor-lapachol showed strong molluscicidal activity against the adult snail (LD(90)<10 ppm) and significant toxicity against snail egg masses (LD(90)<0.2 ppm). As lapachol is easily extracted, and the derivatives can be synthesised without any difficulty, large-scale synthesis and field tests can be conducted, with a view to large-scale molluscicidal programs.


Assuntos
Moluscocidas/farmacologia , Naftoquinonas/farmacologia , Caramujos/crescimento & desenvolvimento , Animais , Anti-Infecciosos/farmacologia , Bioensaio , Brasil , Naftoquinonas/química , Caramujos/efeitos dos fármacos
10.
Arzneimittelforschung ; 50(12): 1120-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11190779

RESUMO

The biological activities of the naphthoquinones lapachol and its cyclization product beta-lapachone, extracted from trees of the genus Tabebuia, have been intensively studied. Given continuity to the studies about heterocyclic derivatives obtained from the reaction of these naphtoquinones with amino-containing reagents, 22 derivatives of beta-lapachone, nor-beta-lapachone and lapachol were synthesised and their activities against trypomastigote forms of T. cruzi were evaluated. The compounds were grouped as oxazolic, imidazolic, phenoxazinic, indolic, pyranic and cyclopentenic derivatives. The variability of the new structures is based on the great electrophilicity of 1,2-quinoidal carbonyls towards reagents containing nitrogen or carbon as nucleophilic centres. In relation to the trypanocidal activity of the synthesised compounds, in view of their structural diversity, tendencies only could be verified. Among the cyclofunctionalised products the oxazolic and imidazolic derivatives showed +/- 1.5 to 34.8 times higher activity than crystal violet, the standard drug for the sterilization of stored blood. These results corroborate the tendency of trypanocidal activity in imidazolic skeletons, and indicate that this moiety could be used as a guide for architectural delineation of molecules with potential value for the chemotherapy of Chagas disease.


Assuntos
Naftoquinonas/farmacologia , Plantas Medicinais/química , Tripanossomicidas/farmacologia , Animais , Brasil , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Espectroscopia de Ressonância Magnética , Naftoquinonas/isolamento & purificação , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Tripanossomicidas/isolamento & purificação , Trypanosoma cruzi/efeitos dos fármacos
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