Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Braz J Microbiol ; 54(3): 1501-1511, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37338788

RESUMO

Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infect, respectively, 67% and 13% of the world population, most commonly causing mild symptoms, such as blisters/ulcers. However, severe conditions such as keratitis, encephalitis, and systemic infections may occur, generally associated with the patient's immunological condition. Although Acyclovir® (ACV) and its analogs are the reference drugs for herpetic infections, the number of ACV-resistant HSV infections is growing exponentially. Therefore, new natural products' bioactive compounds have been studied to develop novel effective anti-herpetics. Trichilia catigua is a plant widely used in traditional medicine, including the treatment of skin diseases and sexual infections. In our study, 16 extracts from the bark of T. catigua, obtained with different solvents and their combinations, were evaluated against HSV-1 AR and HSV-2, respectively, ACV resistance and genital strains in vitro. The extracts with the highest selectivity index were used to prepare new topical anti-herpetic formulations and confirmed in vivo. Two new topical formulations were suggested to treat cutaneous and genital herpetic recurrent lesions. The cytotoxicity and antiviral activity were tested using the MTT method. The cytotoxic (CC50) and inhibitory (IC50) concentrations of 50% and the selectivity index (SI: CC50/IC50) were determined. Tc12, Tc13, and Tc16 were added to the formulations. Infected BALB/c mice were treated for 8 days, and the severity of the herpetic lesions was analyzed daily. All CEs showed a CC50 value ranging from 143 to 400 µg/mL, except for Tc3 and Tc10. Tc12, Tc13, and Tc16 showed the best SI in the 0 h, virucidal, and adsorption inhibition assays. In the in vivo test against HSV-1 AR, the infected animals treated with creams were statistically different from the infected non-treated animals and similar to ACV-treated mice. In HSV-2-infected genitalia, similar effects were found for Tc13 and Tc16 gels. The present study demonstrated that extracts from the bark of T. catigua, traditionally used in folk medicine, are a valuable source of active compounds with anti-herpetic activity. The extracts showed a virucidal mechanism of action and prevented the initial stages of viral replication. The cutaneous and genital infections were strongly inhibited by the Tc12, Tc13, and Tc16 extracts. New topical therapeutic alternatives using Trichilia catigua extracts are suggested for patients infected with ACV-resistant strains of HSV.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Meliaceae , Camundongos , Animais , Aciclovir/farmacologia , Aciclovir/uso terapêutico , Reinfecção , Antivirais/farmacologia , Antivirais/uso terapêutico , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 2/fisiologia , Genitália
2.
Biomacromolecules ; 23(10): 4041-4052, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-36173245

RESUMO

Herpes simplex virus type 1 (HSV-1) is a persistent human pathogen, and the emergence of strains resistant to Acyclovir (ACV, reference drug) shows the urgency to develop new treatments. We report the antiherpetic mechanism of the action of lasiodiplodan (LAS-N, (1 → 6)-ß-d-glucan) and its sulfonated derivative (LAS-S3) in vitro and in vivo. LAS-S3 showed anti-HSV-1 action with high selectivity indices for HSV-1 KOS (88.1) and AR (189.2), sensitive and resistant to ACV, respectively. LAS-S3 inhibited >80% of HSV-1 infection in different treatment protocols (virucidal, adsorption inhibition, and post-adsorption effects), even at low doses, and showed a preventive effect and DNA and protein synthesis inhibition. The antiherpetic effect was confirmed in vivo by the cosmetic LAS-S3-CRÈME decreasing cutaneous lesions of HSV-1, including the AR strain. LAS-S3 possessed a broad-spectrum mechanism of action acting in the early and post-adsorption stages of HSV-1 infection, and LAS-S3-CRÈME is a potential antiherpetic candidate for patients infected by HSV-1-resistant strains.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Aciclovir/farmacologia , Aciclovir/uso terapêutico , Antivirais/farmacologia , Glucanos/farmacologia , Herpes Simples/tratamento farmacológico , Humanos
3.
Rev. bras. farmacogn ; 27(2): 254-271, Mar.-Apr. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-843813

RESUMO

ABSTRACT Medicinal plants play an important role in human health care. It is estimated that about 25–30% of all drugs are evaluated as therapeutic agents derived from natural products. Research in the pharmaceutical industry has demonstrated that for complex diseases, natural products still represent a valuable source for the production of new chemical compounds, since they possess privileged structures. Among Brazilian biodiversity, "catuaba" is popularly used as a tonic to treat fatigue, stress, impotence, memory deficits, and digestive disorders. Studies show antibacterial, trypanocidal, antioxidant, antiarrhythmic, antidepressant, improvement of memory, anti-inflammatory and antinociceptive activities, as well as phytocosmetic activity in cellulite treatment and in anti-ageing. The Brazilian plants known and used as catuaba are represented by more than twenty different species; however, the plant most commonly found in Brazil as "catuaba" is the species Trichilia catigua A. Juss., Meliaceae. Thus, the aim of this paper is to present a review of T. catigua, with emphasis on biological activities, chemical and analytical development and formulations in order to provide a broader and deeper insight, seeking a herbal medicine and/or phytocosmetic as well as future prospects for commercial exploitation and directions for future studies.

4.
Anal Sci ; 21(3): 235-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15790105

RESUMO

Numerical taxonomy characterization of Baccharis genus species was performed using ultraviolet-visible spectrophotometry. The aim was to present a more convenient, more practical, more economic and faster method based on chemometric methods and UV-vis absorbance to give the most information about species identity and discrimination, especially when their classification has been doubtful. Three Baccharis species: B. genistelloides Persoon var. trimera (Less.) DC, B. milleflora (Less.) DC, and B. articulata (Lam.) Persoon were included in the study. With the help of principal component analysis (PCA) and cluster analysis (CA), we could characterize the three species. Application of soft independent modeling of class analogy (SIMCA) and K-nearest neighbor (KNN) methods on a training set of 65 extracts resulted in models that correctly classified all samples of an independent validation set, eight samples of B. genistelloides Persoon var. trimera (Less.) DC and one sample donated by Prof. Alarich Schultz Herbarium, Porto Alegre-RS, Brazil.


Assuntos
Baccharis/química , Baccharis/classificação , Classificação/métodos , Espectrofotometria Ultravioleta/métodos , Extratos Vegetais/química , Especificidade da Espécie
5.
Anal Sci ; 19(7): 1013-7, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12880084

RESUMO

Phytochemical investigation of the aerial parts of three Baccharis species (Asteraceae family) was performed using HPLC and chemometric methods, with the objective of distinguishing between three morphologically very similar species: Baccharis genistelloides Persoon var. trimera (Less.) DC, B. milleflora (Less.) DC and B. articulata (Lam.) Persoon. With the help of Principal Component Analysis (PCA) and variance weights, it was possible to characterize the chromatographic profiles of the alcoholic extracts of the three species. Application of Soft Independent Modeling of Class Analogy (SIMCA) and K-Nearest Neighbor (KNN) methods on a training set of 74 extracts resulted in models that correctly classified all eight samples in an independent test set.


Assuntos
Baccharis/química , Baccharis/classificação , Cromatografia Líquida de Alta Pressão/métodos , Análise de Componente Principal/métodos , Componentes Aéreos da Planta/química , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...