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- The phytochemical and bioactivity profiles of wild Calluna vulgaris L. flowersPublication . Rodrigues, Francisca; Moreira, Teresa; Pinto, Diana; Pimentel, Filipa B.; Costa, Anabela S.G.; Nunes, M. Antónia; Gonçalves Albuquerque, Tânia; S. Costa, Helena; Palmeira-de-Oliveira, Ana; Oliveira, Ana Isabel; Sut, Stefania; Dall'Acqua, Stefano; Oliveira, M. Beatriz P.P.The nutritional composition of Calluna vulgaris flowers as well as the phytochemical profile, antioxidant (DPPH and FRAP assays), antimicrobial and cytotoxic (in human immortalized non-tumorigenic keratinocyte and fibroblasts) activities of aqueous, hydroalcoholic and ethanolic extracts were evaluated. A high content of fiber and carbohydrates (75%) and the prevalence of α-tocopherol as vitamer deserves attention. Linolenic (35%), linoleic (27%) and palmitic (21%) acids were the most abundant fatty acids. Qualitative and quantitative analysis by LC-MS and 1NMR indicated high levels of quercetin, kaempferol and myricetin derivatives as well as procyanidins. The hydro-alcoholic extract displayed the highest antioxidant activity and total phenolics (TPC) and flavonoid contents (TFC). No adverse effects on cells were observed until a concentration of 100 μg/mL and a good antimicrobial activity was reported against S. epidermidis and S. aureus with the hydro-alcoholic extract. The data obtained demonstrated that wild plants like heather, although not being a common nutritional reference, can be used in an alimentary base as a source of bioactive compounds, namely antioxidants.
- Livro de atas do IX Colóquio de FarmáciaPublication . Cruz, Agostinho; Cunha, Agostinho; Oliveira, Ana Isabel; Jesus, Ângelo; Pinho, Cláudia; Santos, Marlene; Correia, Patrícia Carla dos Santos; Ferraz Oliveira, RitaLivro de Atas do “IX Colóquio de Farmácia”: “Envelhecimento e Saúde” da “9 th Pharmacy Academic Conference Proceedings” em Abril de 2013.
- O conceito da qualidade nos produtos à base de Ginkgo biloba comercializados em PortugalPublication . Pinho, Cláudia; Correia, Patrícia; Cunha, Agostinho; Jesus, Ângelo; Oliveira, Ana Isabel; Ferraz Oliveira, Rita; Santos, Marlene; Cruz, AgostinhoO extracto de Ginkgo biloba é o produto fitoterápico mais vendido na Europa. Em Portugal e muitos países, a maioria dos produtos à base de plantas são comercializados como suplementos alimentares, não estando garantidos, parâmetros de qualidade, segurança e eficácia. Realizouse um estudo, com recolha de informações, tendo por base uma amostra de 50 produtos à base de ginkgo. Da análise, verificou-se que 94% podiam ser encontrados à venda na internet, e desse total, 89% possuíam informação on-line quanto à composição. Apenas 40% referem a utilização do extracto padronizado de ginkgo e muitos recomendam doses superiores às referidas como terapêuticas.
- Phenotypic impact of deregulated expression of class I histone deacetylases in urothelial cell carcinoma of the bladderPublication . Neto, Susana; Quintela Vieira, Ana Filipa; Montezuma, Diana; Costa, Natália R.; Antunes, Luís; Baptista, Tiago; Oliveira, Ana Isabel; Pinho dos Santos Graça, Maria Inês; Rodrigues, Ângelo; Magalhães, José S.; Oliveira, Jorge; Henrique, Rui; Jerónimo, CarmenDeregulated expression of histone deacetylases (HDACs) has been implicated in tumorigenesis. Herein, we investigated class I HDACs expression in bladder urothelial cell carcinoma (BUCC), its prognostic value and biological significance. Significantly increased transcript levels of all HDACs were found in BUCC compared to 20 normal mucosas, and these were higher in lower grade and stage tumors. Increased HDAC3 levels were associated with improved patient survival. SiRNA experiments showed decrease cell viability and motility, and increased apoptosis. We concluded that class I HDACs play an important role in bladder carcinogenesis through deregulation of proliferation, migration and apoptosis, constituting putative therapeutic targets.
- Análise da rotulagem de suplementos alimentares utilizados no Sistema Nervoso CentralPublication . Ferreira, Liliana; Oliveira, Ana Isabel; Pinho, CláudiaOs suplementos alimentares (SA) têm um papel importante na manutenção da saúde da população e diversos benefícios demonstrados (Silveira, Bandeira, & Arrais, 2008). No entanto, a crença errónea por parte dos consumidores de que estes são isentos de risco e as escassas obrigações legais requeridas para a sua entrada no mercado têm servido de alerta para a necessidade de mais investigação (Axon, Vanova, Edel, & Slack, 2017). Analisar, do ponto de vista legal e científico, a informação disponibilizada na rotulagem dos SA à base de plantas utilizados para alguns dos principais problemas associados ao sistema nervoso central (insónia, ansiedade, nervosismo e depressão), comercializados em Portugal em Farmácias Comunitárias e Ervanárias/Lojas Dietéticas.
- Atividade antioxidante de espécies de EuphorbiaPublication . Ribeiro, Alexandre; Oliveira, Ana Isabel; Pinho, CláudiaAs plantas constituem importantes fontes de compostos bioativos, com uma grande variedade de atividades biológicas. Quando sujeitas a stress, as células produzem espécies reativas de oxigénio que podem causar danos para a saúde humana, estando associadas a doenças cardiovasculares, neurodegenerativas e cancro. Destacam-se atualmente os compostos com potencial antioxidante, associados ao tratamento e prevenção de doenças. Muitas espécies da família das Euphorbiaceae têm sido utilizadas como medicina tradicional nos países do mediterrâneo, incluindo Portugal. O trabalho tem como objetivo avaliar a capacidade antioxidante de dois extratos metanólicos de espécies do género Euphorbia (E. paralias e E. hirsuta).
- Development, characterization, antioxidant and hepatoprotective properties of poly(Ɛ-caprolactone) nanoparticles loaded with a neuroprotective fraction of Hypericum perforatumPublication . Oliveira, Ana Isabel; Pinho, Cláudia; Fonte, Pedro; Sarmento, Bruno; Dias, Alberto C.P.Quercetin and biapigenin are antioxidant and neuroprotective compounds present in Hypericum perforatum, with potential application in neurodegenerative diseases. Quercetin has shown to have excellent antioxidant activities. Biapigenin possesses a distinctive mechanism of action, preventing the onset of calcium deregulation and mitochondrial dysfunction. The main aim of this study was to establish a new delivery system encapsulating H. perforatum neuroprotective fraction, isolated from it,containing quercetin and biapigenin into poly(Ɛ-caprolactone) (PCL) nanoparticles. It also aimed to study its hepatoprotective potential. Different formulation parameters were optimized, resulting in a stable formulation of polymer:compounds ratio 1:0.1 with a mean particle size of 185nm, zeta potential around -20mV and association efficiency close to 100%. Compounds in vitro release, under physiological conditions, showed an initial burst followed by a sustained release. The antioxidant functional properties of these compounds were not altered by encapsulation. PCL-loaded nanoparticles protected HepG2 cells from intrinsic compound toxicity at high concentrations. Depending on the incubation regimen, quercetin-biapigenin PCL-loaded nanoparticles or free compounds were more effective in protecting HepG2 cells against tert-butylhydroperoxide-induced toxicity. This is the first report of the encapsulation of a quercetin-biapigenin mixture in a polymeric matrix, specifically, in PCL, with synergic anti-oxidant and hepatoprotective effects.
- Plantas africanas com atividade citotóxicaPublication . Santos, Roberta; Veiga, Inês; Cruz, Agostinho; Ferraz Oliveira, Rita; Pinho, Cláudia; Oliveira, Ana IsabelO cancro é a segunda causa de morte, globalmente, atingindo uma em cada seis pessoas, em 2018. Os tipos de cancros mais prevalentes são o cancro da mama, próstata, colorretal, pulmão, colo do útero e estômago. O continente africano possui um amplo património de plantas, muitas ainda por explorar, e outras que têm demonstrado atividades diversas como, antioxidante, anti-inflamatória, antimicrobiana e/ou anticancerígena. Além disso, muitos pacientes apenas têm acesso a medicina tradicional o que inclui o uso de plantas medicinais, face a problemas económicos. Desta forma, a procura de evidências acerca das plantas com potencial atividade anticancerígena é importante. Compilar informação sobre atividade anticancerígena de plantas existentes no continente africano.
- Synergistic activity of cold pressed seed oils from Indian neem (Azadirachta indica), karanja (Pongamia glabra) and aloe vera gel (Aloe barbadensis) in a cosmeceutical moisturizerPublication . Ferraz Oliveira, Rita; Barreiros, Luisa; Cruz, Agostinho; Oliveira, Ana Isabel; Dias, A; Pinho, Cláudia; Fernandes, S; Santos, NM; Morgado, JThe increased interest and knowledge on the beneficial activity of plants and their compounds in human health have contributed to the development of several drugs, widely used in clinical practice worldwide
- Chemistry, bioactivities, extraction and analysis of azadirachtin: State-of-the-artPublication . Fernandes, Sara; Barreiros, Luisa; Ferraz Oliveira, Rita; Cruz, Agostinho; Prudêncio, Cristina; Oliveira, Ana Isabel; Pinho, Cláudia; Santos, Nuno; Morgado, JoaquimAzadirachta indica A. Juss. (Neem) is an Indian tree recognized for its activity as pesticide, as well as several pharmacological properties. Among the various compounds already isolated and studied from Neem tree, azadirachtin (AZA) was identified as the main bioactive compound. Azadirachtin can be found at different parts of the Neem plant but assumes its maximum concentration at the seed level. This compound features a quite complex chemical structure, which justifies the 20-plus-year difficulty to identify the synthetic pathway that subsequently permitted to carry out its artificial synthesis. Azadirachtin is widely used as a basis for production of biopesticides; nevertheless, other properties have been recognized for this substance, among which the anticancer and antimalarial activity stand out. The methods available for azadirachtin extraction are diverse, including solid-liquid extraction and extraction with solvents at high or low temperatures. Alcohol based solvents are associated with higher extraction yields and are therefore preferred for the isolation of azadirachtin from plant parts. Clean-up of the extracts is generally required for further purification. The highest azadirachtin levels have been obtained from Neem seeds but concentration values present a large variation between batches. Therefore, in addition to extraction procedures, it is essential to establish routine methods for azadirachtin identification and quantification. Chromatography-based techniques are preferably selected for detection and quantification of azadirachtin in plant matrices. Overall, this process will guarantee a future reproducible, safe and effective use of the extracts in formulations for commercial applications.
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