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1.
Int J Cosmet Sci ; 45(6): 815-833, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37565318

RESUMO

OBJECTIVE: Sisal is a common stiff fibre produced around the world, corresponding to approximately 70% of the commercial production of all fibres of this type. The fibres are extracted from the leaves of Agave sisalana, from which approximately 4% of their weight is obtained, with the remaining 96% considered to be residues from the process of the sisal industry. The objective of this work was to obtain a polyphenol-enriched extract from the A. sisalana residue by ultrasonically assisted extraction, characterize it chemically, evaluate in vitro antioxidant activity, and develop safe and stable photoprotective formulations for future application in cosmetic preparations. METHODS: Ultrasonic extraction of solid plant material was performed using 50% ethanol/water (v/v). The extract was chemically characterized by high-performance liquid chromatography equipment associated with classical molecular networking and evaluated for in vitro antioxidant activity by different methodologies. Ten formulations were prepared, varying the component concentrations and the shear time. The 1.0% sisal extract was incorporated into the most stable formulations, and preliminary and accelerated stability were evaluated. The emulsions were investigated for safety by assessment of primary accumulated dermal irritability and sensitization and a dermatological clinical study of phototoxicity and photosensitization. The photoprotective formulations containing or not containing the extract that were stable after 90 days had their in vivo sun protection factor (SPF), UVA protection factor, critical wavelength, and protection against visible and blue light determined. RESULTS: Ultrasound extraction using 50% ethanol/water (EH 50) as an extractor vehicle showed the best yield. The extract exhibited a concentration of phenolic compounds (77.93 mg of equivalent to the standard gallic acid/g) and showed in vitro antioxidant activity. Emulsions without and with 1.0% sisal extract remained stable and safe. The addition of the extract to the photoprotective formulation statistically increased the SPF when compared to the formulation without the extract and offered protection against UVA radiation, critical wavelengths, and absorption of visible and blue light. CONCLUSION: Based on the findings, the solid residue of A. sisalana may be indicated as a component of photoprotective and antioxidant cosmetic formulations.


OBJECTIF: Le sisal est une fibre rigide courante produite dans le monde entier, correspondant à environ 70 % de la production commerciale de toutes les fibres de ce type. Les fibres sont extraites des feuilles d'Agave sisalana dont environ 4 % du poids est obtenu, les 96 % restants étant considérés comme des résidus du procédé de l'industrie du sisal. L'objectif de ce projet était d'obtenir un extrait du résidu d'A. sisalana enrichi en polyphénols par extraction assistée par ultrasons (EAU), de le caractériser chimiquement, d'évaluer l'activité antioxydante in vitro et de développer des formulations photoprotectrices sûres et stables pour une application future dans des préparations cosmétiques. MÉTHODES: L'extraction ultrasonique de la matière végétale solide a été effectuée avec une solution à 50 % d'éthanol/eau (v/v). L'extrait a été chimiquement caractérisé avec un équipement de chromatographie en phase liquide à haute performance associé à un réseau moléculaire (RM) classique, puis évalué pour l'activité antioxydante in vitro par différentes méthodologies. Dix formulations ont été préparées en variant les concentrations des composants et le temps de cisaillement. L'extrait de sisal à 1,0 % a été incorporé dans les formulations les plus stables et la stabilité préliminaire et accélérée a été évaluée. La sécurité d'emploi des émulsions a été étudiée en évaluant l'irritabilité et la sensibilisation cutanées accumulées primaires et l'étude clinique dermatologique de la phototoxicité et de la photosensibilisation. Le facteur de protection solaire in vivo, le facteur de protection UVA, la longueur d'onde critique et la protection contre la lumière visible et bleue ont été déterminées pour les formulations photoprotectrices contenant ou non l'extrait qui étaient stables après 90 jours. RÉSULTATS: L'extraction par ultrasons utilisant une solution à 50 % d'éthanol/eau (EH 50) comme véhicule d'extraction a menée au meilleur rendement. L'extrait a présenté une concentration de composés phénoliques (77,93 mg d'EAG/g) et une activité antioxydante in vitro. Les émulsions sans et avec 1,0 % d'extrait de sisal sont restées stables et sans danger. L'ajout de l'extrait à la formulation photoprotectrice a statistiquement augmenté le SPF par rapport à la formulation sans extrait et a offert une protection contre les rayonnements UVA, la longueur d'onde critique et l'absorption de la lumière visible et bleue. CONCLUSION: D'après ces résultats, les résidus solides d'A. sisalana peuvent être indiqués comme composant des formulations cosmétiques photoprotectrices et antioxydantes.


Assuntos
Agave , Cosméticos , Resíduos Industriais , Agave/química , Antioxidantes/farmacologia , Extratos Vegetais , Etanol , Água
2.
Bol. latinoam. Caribe plantas med. aromát ; 19(3): 247-288, mayo 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1116290

RESUMO

Selaginella is the only genus from Selaginellaceae, and it is considered a key factor in studying evolution. The family managed to survive the many biotic and abiotic pressures during the last 400 million years. The purpose of this review is to provide an up-to-date overview of Selaginella in order to recognize their potential and evaluate future research opportunities. Carbohydrates, pigments, steroids, phenolic derivatives, mainly flavonoids, and alkaloids are the main natural products in Selaginella. A wide spectrum of in vitro and in vivo pharmacological activities, some of them pointed out by folk medicine, has been reported. Future studies should afford valuable new data on better explore the biological potential of the flavonoid amentoflavone and their derivatives as chemical bioactive entities; develop studies about toxicity and, finally, concentrate efforts on elucidate mechanisms of action for biological properties already reported.


Selaginella es el único género de Selaginellaceae, y se considera un factor clave en el estudio de la evolución. La familia logró sobrevivir a las muchas presiones bióticas y abióticas durante los últimos 400 millones de años. El propósito de esta revisión es proporcionar un resumen actualizado de Selaginella para reconocer su potencial y evaluar futuras oportunidades de investigación. Los hidratos de carbono, pigmentos, esteroides, derivados fenólicos, principalmente flavonoides, y alcaloides son los principales productos naturales en Selaginella. Se ha informado un amplio espectro de actividades farmacológicas in vitro e in vivo, algunas de ellas señaladas por la medicina popular. Los estudios futuros deberían proporcionar datos nuevos y valiosos para explorar mejor el potencial biológico de la amentoflavona flavonoide y sus derivados como entidades bioactivas químicas; desarrollar estudios sobre la toxicidad y, finalmente, concentrar los esfuerzos en dilucidar los mecanismos de acción para las propiedades biológicas ya informadas.


Assuntos
Extratos Vegetais/farmacologia , Extratos Vegetais/química , Selaginellaceae/química , Flavonoides/análise , Alcaloides/análise , Medicina Tradicional
3.
São Paulo med. j ; 133(4): 336-342, July-Aug. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-763367

RESUMO

CONTEXT AND OBJECTIVE:Impaired local cell immunity seems to contribute towards the pathogenesis and progression of cervical intraepithelial neoplasia (CIN), but the underlying molecular mechanisms promoting its progression remain unclear. Identification of new molecular markers for prognosis and diagnosis of early-stage CIN may aid in decreasing the numbers of CIN cases. Several novel immunoregulatory molecules have been discovered over the past few years, including the human leukocyte antigen G (HLA-G), which through interaction with its receptors exerts important tolerogenic functions. Several lines of evidence suggest that T-helper interleukin-17 (IL-17)-producing cells (Th17 cells) may play a role in antitumor immunity. However, recent reports have implicated Th17 cells and their cytokines in both pro and anti-tumorigenic processes. The aim of the study was to evaluate the roles of HLA-G and Th17 in the immunopathogenesis of CIN I.DESIGN AND SETTING:Analytical cross-sectional study with a control group using 58 cervical specimens from the files of a public university hospital providing tertiary-level care.METHODS:We examined HLA-G and IL-17 expression in the cervical microenvironment by means of immunohistochemistry, and correlated these findings with clinical and pathological features.RESULTS:There was a greater tendency towards HLA-G and IL-17 expression in specimens that showed CIN I, thus suggesting that these molecules have a contribution towards cervical progression.CONCLUSION:These findings suggest that HLA-G and IL-17 expression may be an early marker for assessing the progression of cervical lesions.


CONTEXTO E OBJETIVO:A deficiência na imunidade celular localizada parece contribuir para a patogênese e progressão das neoplasias intraepiteliais cervicais (NIC), no entanto, ainda não está totalmente esclarecido o mecanismo molecular fundamental nesse processo de progressão. A identificação de novos marcadores moleculares de prognóstico e diagnóstico das NIC em estágios precoces pode ajudar a diminuir a quantidade de casos de NIC. Várias novas moléculas com função imunorregulatória foram descobertas nos últimos anos, inclusive o antígeno leucocitário humano G (HLA-G), que, através de interação com os receptores, tem importantes funções tolerogênicas. Diversas linhas de evidência sugerem que as células T-ajudantes produtoras de interleucina-17 (IL-17, células Th17), podem desempenhar um papel na imunidade antitumoral. Porém, recentes relatos implicaram as células Th17 e suas citocinas tanto em processos pro- quanto anti-tumorigênicos. O objetivo do estudo foi avaliar o papel do HLA-G e Th17 na imunopatogênese das NIC I.TIPO DE ESTUDO E LOCAL:Estudo transversal analítico com grupo controle em 58 espécimes cervicais dos arquivos de um hospital universitário público com assistência prestada no nível terciário.MÉTODOS:Avaliamos a expressão de HLA-G e IL-17 por imunoistoquímica no microambiente cervical, associando esses achados com as características clínico-patológicas.RESULTADOS:Houve tendência aumentada da expressão de HLA-G e IL-17 em espécimes que apresentaram NIC I, sugerindo que essas moléculas têm contribuição na progressão cervical.CONCLUSÃO:Estes resultados sugerem que a expressão do HLA-G e da IL-17 pode ser um marcador precoce para avaliar a progressão das lesões cervicais.


Assuntos
Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Displasia do Colo do Útero/metabolismo , Colo do Útero/metabolismo , Antígenos HLA-G/metabolismo , /metabolismo , Neoplasias do Colo do Útero/metabolismo , Fatores Etários , Biomarcadores Tumorais/metabolismo , Biópsia , Displasia do Colo do Útero/patologia , Colo do Útero/patologia , Coito/fisiologia , Estudos Transversais , Antígenos HLA-G/análise , Imuno-Histoquímica/métodos , /análise , Parceiros Sexuais , Neoplasias do Colo do Útero/patologia
4.
Sao Paulo Med J ; 133(4): 336-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25351636

RESUMO

CONTEXT AND OBJECTIVE: Impaired local cell immunity seems to contribute towards the pathogenesis and progression of cervical intraepithelial neoplasia (CIN), but the underlying molecular mechanisms promoting its progression remain unclear. Identification of new molecular markers for prognosis and diagnosis of early-stage CIN may aid in decreasing the numbers of CIN cases. Several novel immunoregulatory molecules have been discovered over the past few years, including the human leukocyte antigen G (HLA-G), which through interaction with its receptors exerts important tolerogenic functions. Several lines of evidence suggest that T-helper interleukin-17 (IL-17)-producing cells (Th17 cells) may play a role in antitumor immunity. However, recent reports have implicated Th17 cells and their cytokines in both pro and anti-tumorigenic processes. The aim of the study was to evaluate the roles of HLA-G and Th17 in the immunopathogenesis of CIN I. DESIGN AND SETTING: Analytical cross-sectional study with a control group using 58 cervical specimens from the files of a public university hospital providing tertiary-level care. METHODS: We examined HLA-G and IL-17 expression in the cervical microenvironment by means of immunohistochemistry, and correlated these findings with clinical and pathological features. RESULTS: There was a greater tendency towards HLA-G and IL-17 expression in specimens that showed CIN I, thus suggesting that these molecules have a contribution towards cervical progression. CONCLUSION: These findings suggest that HLA-G and IL-17 expression may be an early marker for assessing the progression of cervical lesions.


Assuntos
Colo do Útero/metabolismo , Antígenos HLA-G/metabolismo , Interleucina-17/metabolismo , Displasia do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/metabolismo , Adulto , Fatores Etários , Biomarcadores Tumorais/metabolismo , Biópsia , Colo do Útero/patologia , Coito/fisiologia , Estudos Transversais , Feminino , Antígenos HLA-G/análise , Humanos , Imuno-Histoquímica/métodos , Interleucina-17/análise , Pessoa de Meia-Idade , Parceiros Sexuais , Neoplasias do Colo do Útero/patologia , Adulto Jovem , Displasia do Colo do Útero/patologia
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