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- Extraction of anthocyanins from red raspberry for natural food colorants development: Processes optimization and in vitro bioactivityPublication . Rocha, Rosiane; Pinela, José; Abreu, Rui M.V.; Añibarro Ortega, Mikel; Pires, Tânia C.S.; Saldanha, Ana Luísa; Alves, Maria José; Nogueira, António José M.; Ferreira, Isabel C.F.R.; Barros, LillianHeat (HAE)-and ultrasound (UAE)-assisted extraction methods were implemented to recover anthocyanins from red raspberry. Processing time, ethanol concentration, and temperature or ultrasonic power were the independent variables combined in five-level rotatable central composite designs coupled with response surface methodology (RSM) for processes optimization. The extraction yield and levels of cyanidin-3-O-sophoroside (C3S) and cyanidin-3-O-glucoside (C3G) were monitored by gravimetric and HPLC-DAD-ESI/MSn methods, respectively, and used as response criteria. The constructed theoretical models were successfully fitted to the experimental data and used to determine the optimal extraction conditions. When maximizing all responses simultaneously, HAE originated slightly higher response values (61% extract weight and 8.7 mg anthocyanins/g extract) but needed 76 min processing at 38â—¦ C, with 21% ethanol (v/v), while the UAE process required 16 min sonication at 466 W, using 38% ethanol (v/v). The predictive models were experimentally validated, and the purple-red extracts obtained under optimal condition showed antioxidant activity through lipid peroxidation and oxidative hemolysis inhibition, and antibacterial effects against food-related microorganisms, such as Escherichia coli and Enterococcus faecalis. These results highlight the potential of red raspberry extracts as natural food colorants with bioactive effects and could be exploited by industries interested in the production of anthocyanin-based products.
- Effect of hidroethanolic extract of Lavandula pedunculata (mill.) Cav. On morphometric parameters in HPV-16 trangenic micePublication . Nascimento-Gonçalves, Elisabete; Ferreira, Teresa; Moutinho, Magda S.S.; Pires, Maria João; Bastos, Margarida M.S.M.; Medeiros, Rui; Nogueira, António José M.; Barros, Lillian; Ferreira, Isabel C.F.R.; Costa, Rui Miguel Gil; Oliveira, Paula A.Lavandula penduculata (Mill.) Cav., common English name French lavender, belongs to the Lamiaceae family and has been used as a medicinal plant in infusions for respiratory and digestive systems and as a therapeutic agent with antiseptic action for cleaning wounds [1,2]. The K14HPV16 mice is a skin squamous carcinoma model that can be used to test the antitumoral properties of several chemical and natural products [3]. The aim of this work was to evaluate the effect of the hydroethanolic French lavender extract (FLE) on body weight, relative organs weights, food and water consumption in an HPV-16-transgenic mice model. The extract was obtained from a maceration with ethanol/water (80:20, v/v), and the phenolic composition was determined through HPLC-DAD-ESI/MS. Twenty-eight male mice were randomly divided into four groups (n=7/group) according to their genotype: group I (HPV16- control); II (HPV16- FLE); III (HPV16+ control) and IV (HPV16+ FLE). The FLE was administrated orally in drinking water at 6.8 mg/10mL/animal to animals from groups II and IV and changed every 4 days. The animals were kept under controlled conditions such as temperature, light and humidity
- Ação do ácido quetomélico nas alterações hematológicas induzidas pela redução de 5/6 de massa renal em ratosPublication . Fonte, Elizabete; Nogueira, António José M.; Pires, Carlos André; Colaço, Bruno Jorge; Oliveira, Paula A.; Pires, Maria JoãoA doença renal crónica está associada com o desenvolvimento de anemia devido principalmente à diminuição da produção de eritropoetina. O ácido quetomélico (AC) é um potente inibidor seletivo da farnesil transferase e, desta forma, inibe as vias de sinalização que levam à progressão da fibrose renal. Assim, o objectivo deste trabalho foi o de estudar os efeitos do tratamento crónico com o AC nas alterações hematológicas induzidas pela redução de 5/6 de massa renal (RMR). Neste estudo foram utilizados 70 ratos machos da estirpe Wistar. Uma semana após a redução cirúrgica de 5/6 de massa renal, os animais foram divididos em quatro grupos experimentais: CO: animais em que se simulou a cirurgia e sem tratamento; CO+AC: animais em que se simulou a cirurgia e tratados com o AC; RMR: animais com RMR e não tratados; RMR+AC: animais com RMR e tratados com o AC. O tratamento foi administrado por via intraperitoneal, durante seis meses. Para o estudo hematológico procedeu-se à contagem manual, em câmara de Neubauer, do número total de eritrócitos e de leucócitos, à determinação do microhematócrio, à contagem diferencial de leucócitos e à estimativa do número total de plaquetas no esfregaço de sangue corado com Diff-Quick. Nos grupos RMR e RMR+AC observou-se um aumento estatisticamente significativo (p<0.01) do número total de eritrócitos, do microhematócrito, do número total de leucócitos e das plaquetas, em relação aos grupos CO e CO+AC. Deste modo, os resultados deste estudo sugerem que em ratos Wistar com doença renal crónica, o tratamento com o AC, durante seis meses, não diminui a gravidade da anemia, da leucocitose e da trombocitose induzidas pela redução de 5/6 de massa renal.
- Pathophysiological mechanisms of renal fibrosis: a review of animal models and therapeutic strategiesPublication . Nogueira, António José M.; Pires, Maria João; Oliveira, Paula A.Chronic kidney disease (CKD) is a long-term condition in which the kidneys do not work correctly. It has a high prevalence and represents a serious hazard to human health and estimated to affects hundreds of millions of people. Diabetes and hypertension are the two principal causes of CKD. The progression of CKD is characterized by the loss of renal cells and their replacement by extracellular matrix (ECM), independently of the associated disease. Thus, one of the consequences of CKD is glomerulosclerosis and tubulointerstitial fibrosis caused by an imbalance between excessive synthesis and reduced breakdown of the ECM. There are many molecules and cells that are associated with progression of renal fibrosis e.g. angiotensin II (Ang II). Therefore, in order to understand the biopathology of renal fibrosis and for the evaluation of new treatments, the use of animal models is crucial such as: surgical, chemical and physical models, spontaneous models, genetic models and in vitro models. However, there are currently no effective treatments for preventing the progression of renal fibrosis. Therefore it is essential to improve our knowledge of the cellular and molecular mechanisms of the progress of renal fibrosis in order to achieve a reversion/elimination of renal fibrosis.
- Conhecimentos relativamente à doação do sangue em alunos de uma instituição de ensino superiorPublication . Gomes, Maria José; Nogueira, António José M.; Teixeira, Cristina; Antão, CelesteA doação de sangue é considerada uma atitude que pode salvar vidas e é atualmente um assunto de relevo dada a crescente necessidade em manter reservas para a transfusão de sangue de emergência. A compreensão de todos aspetos subjacentes à atitude de ser dador permitirá perspetivar metodologias e programas direcionadas para ações específicas, de forma a aumentar o nível de conhecimento da população nesta matéria, bem como para motivar atitudes positivas face à doação de sangue. Objetivo: Avaliar os conhecimentos, atitudes, opiniões e motivações relativamente à doação do sangue em estudantes do ensino superior. Material e métodos Estudo descritivo tendo como elegíveis os estudantes de uma instituição de ensino superior (Norte de Portugal). Foi construído um questionário com questões em quatro domínios: conhecimentos, atitudes, opiniões e motivações relativamente à doação de sangue. Os dados foram obtidos por auto-aplicação do questionário. Com base nas 17 questões que avaliam os conhecimentos, criaram-se três categorias: baixo (0 a 7 respostas certas), médio (8 a 13 respostas certas) e alto (14 a 17 respostas certas). Resultados Dos 1,140 alunos a frequentar os diferentes cursos 380 (33%), foram convidados a participar e destes apenas 2% (n=8) recusaram. Dos 372 inquiridos, 83% são do género feminino, 84% têm idade inferior a 23 anos e 48% frequentam o 1º ano. Dos participantes 13% (n= 48) doaram sangue pelo menos uma vez e 7% (n=26) fazem-no de forma regular. O nível de conhecimentos revelado é baixo para 16% (n=61) e alto para 13% (n=42). Relativamente a atitudes, 98% (n=366) doariam sangue num apelo urgente, igual percentagem o faria para um familiar ou amigo, 68% (n=254) afirmam que as campanhas de sensibilização influenciam a doação de sangue e 21% (n=79) doariam sangue se recebessem incentivo monetário. No domínio das opiniões, 20% (n=73) dos inquiridos referiram ter receio de contrair doenças ao doar sangue, 83% (n=311) confiam no material utilizado e 60% (n=224) consideram que a informação existente sobre dádiva de sangue é insuficiente. No que respeita à motivação para a dádiva de sangue, os fatores mais referidos como importantes foram, o dever cívico, a falta de sangue nos serviços de saúde e a qualidade de atendimento, respectivamente, para 72% (n=268), 87% (n=323) e 70% (n=259) dos inquiridos. Conclusões É de salientar a baixa proporção de dadores nesta amostra tendo em conta que são indivíduos pertencentes ao grupo etário onde é mais expectável a dádiva de sangue. No entanto, quase a totalidade estaria disponível para doar sangue. O sentido de dever cívico, a qualidade do atendimento e a falta de sangue nos serviços de saúde são fatores motivacionais para a dádiva de sangue. Considera-se importante fornecer informação e formação sobre a doação de sangue, concretamente no que se refere fatores impeditivos, locais de colheita e riscos associados. São necessárias estratégias de abordagem que realcem o papel do dador na sociedade.
- Motivations and attitudes towards the act of blood donation among undergraduate health science studentsPublication . Gomes, Maria José; Nogueira, António José M.; Antão, Celeste; Teixeira, CristinaUndergraduate students are a target for blood donation, as they constitute a young healthy and well-informed group. Aim: To understand motivations and attitudes underpinning the act of blood donation among undergraduate health science students. Materials and methods: Cross-sectional study enrolling undergraduate students of a College of Health Sciences in the Northeast of Portugal (January/February, 2017). Data collection tool was a self-administered questionnaire covering questions about motivations (n = 8) and attitudes (n = 5) towards the act of blood donation. Participants were classified by donation status into donors (one previous donation) and non-donors (never donated). Multiple logistic regression models were used to assess the association between each attitude and motivation on donation status. Odds-ratio (OR) and respective 95% confidence intervals (95%CI) adjusted for potential confounders, were obtained. Results: Out of 362 participants, 12.7% (n = 46) had ever donated blood and 56.5% (n = 26) of them were regular donors. Out of 316 non-donors, 88.0% (n = 278) will donate blood under request. There were no differences between donors and non-donors regarding the attitudes towards blood donation. From all motivations only “be a civic duty” had a significant impact on donor status, such that participants reporting this motivation are more likely to be blood donors (OR = 2.58; IC95%:1.34-4.99) than their counterparts. Conclusion: This study revealed that 80.0% of undergraduate health science students are non-donors, but they are available to donate blood under request. Campaigns and advertising methods focused on the emergent needs for blood donation could play an important role in the recruitment of new donors among undergraduate students
- Histological lesions in hpv16-transgenic model: the effect of hidroethanolic extract of Lavandula pedunculata (mill.) Cav.Publication . Ferreira, Tiago; Nascimento-Gonçalves, Elisabete; Moutinho, Magda S.S.; Pires, Maria João; Bastos, Margarida M.S.M.; Medeiros, Rui; Nogueira, António José M.; Barros, Lillian; Ferreira, Isabel C.F.R.; Costa, Rui Miguel Gil; Rosa, Eduardo; Oliveira, Paula A.The K14HPV16 mice is a skin squamous carcinoma model that can be used to test antitumoral properties of several chemical and natural compounds1. Lavandula penduculata (Mill.) Cav., known as lavender, belongs to the Laminaceae family and has been used in traditional medicine as infusions to treat several conditions2. This work aimed to evaluate the effects of the hydroethanolic French lavender extract (FLE) in an HPV16-transgenic mice model lesions. The extract was obtained through a maceration with ethanol/water (80:20, v/v) and its phenolic composition was determined by HPLC-DADESI/ MS. The FLE was dissolved in drinking water at 6.8 mg/10mL/animal and the animals were supplemented during 29 consecutive days. Twentyeight male mice were randomly divided into four groups: (n=7/group): group I (HPV16- control); II (HPV16- FLE); III (HPV16+ control) and IV (HPV16+ FLE). After 29 days all animals were sacrificed by xylazineketamine overdose following cardiac puncture to obtain blood samples. Skin samples (chest and ear), kidney, liver and spleen were processed for histological analysis.A total of thirteen compounds were identified in the hydroethanolic extract, being salvianolic acid B and rosmarinic acid the main molecules present. Moreover, the compounds revealed to be stable in the drinking water for 5 days. Histological analyses of skin samples from wild-type mice exposed (group II) and not exposed (group I) to FLE showed normal skin histology. Group III showed skin chest epidermal hyperplasia in 100% of the mice while group IV showed less epidermal hyperplasia frequency (66.6%) (p>0.05). Concerning to liver, kidney, and spleen lesions there are no differences between groups (p>0.05). The lavender extract did not prevent the progression of HPV-16 induced cutaneous lesions in this model. These data deserve more investigation to clarify the effect of lavender extract on HPV-16 lesions.
- The cyclooxigenase-2 inhibitor parecoxib prevents epidermal dysplasia in HPV16-transgenic mice: efficacy and safety observationsPublication . Ferreira, Tiago; Campos, Sandra; Silva, Mónica; Ribeiro, Rita; Santos, Susana; Almeida, José L.S.; Pires, Maria João; Costa, Rui Miguel Gil; Córdova, Cláudia; Nogueira, António José M.; Neuparth, Maria João; Medeiros, Rui; Bastos, Margarida M.S.M.; Gaivão, Isabel; Peixoto, Francisco P.; Oliveira, Maria Manuel; Oliveira, Paula A.Carcinogenesis induced by high-risk human papillomavirus (HPV) involves inflammatory phenomena, partially mediated by cyclooxigenase-2. In pre-clinical models of HPV-induced cancer, cyclooxygenase-2 inhibitors have shown significant e cacy, but also considerable toxicity. This study addresses the chemopreventive e ect and hepatic toxicity of a specific cyclooxigensase-2 inhibitor, parecoxib, in HPV16-transgenic mice. Forty-three 20 weeks-old female mice were divided into four groups: I (HPV16+/-, n = 10, parecoxib-treated); II (HPV16+/- n = 11, untreated); III (HPV16+/-, n = 11, parecoxib-treated) and IV (HPV16+/- n = 11, untreated). Parecoxib (5.0 mg/kg once daily) or vehicle was administered intraperitoneally for 22 consecutive days. Skin lesions were classified histologically. Toxicological endpoints included genotoxic parameters, hepatic oxidative stress, transaminases and histology. Parecoxib completely prevented the onset of epidermal dysplasia in HPV16+/- treated animals (0% versus 64% in HPV16+/- untreated, p = 0.027). Parecoxib decreases lipid peroxidation (LPO) and superoxide dismutase (SOD) activity and increases the GSH:GSSG ratio in HPV16+/- treated animals meaning that oxidative stress is lower. Parecoxib increased genotoxic stress parameters in wild-type and HPV16-transgenic mice, but didn’t modify histological or biochemical hepatic parameters. These results indicate that parecoxib has chemopreventive e ects against HPV16-induced lesions while maintaining an acceptable toxicological profile in this model.
- Toxicological and anti-tumor effects of a linden extract (Tilia platyphyllos Scop.) in a HPV16-transgenic mouse modelPublication . Patwal, Tiago; Nascimento-Gonçalves, Elisabete; Macedo, Sara; Borges, Inês; Gama, Adelina; Costa, Rui Miguel Gil; Neuparth, Maria João; Lanzarin, Germano; Venâncio, Carlos; Félix, Luís; Gaivão, Isabel; Alvarado, Antonieta; Pires, Maria João; Bastos, Margarida M.S.M.; Medeiros, Rui; Nogueira, António José M.; Barros, Lillian; Ferreira, Isabel C.F.R.; Rosa, Eduardo; Oliveira, Paula A.Tilia platyphyllos Scop. is a popular broad-leaved tree, native to Central and Southern Europe. Hydroethanolic extracts rich in phenolic compounds obtained from T. platyphyllos Scop. have shown in vitro antioxidant, anti-inflammatory and antitumor properties. The aim of this work was to evaluate the therapeutic properties of a hydroethanolic extract obtained from T. platyphyllos in HPV16-transgenic mice. The animals were divided into eight groups according to their sex and phenotype. Four groups of female: HPV+ exposed to linden (HPV linden; n = 6), HPV+ (HPV water; n = 4), HPV- exposed to linden (WT linden; n = 5) and HPV- (WT water; n = 4) and four groups of male: HPV+ exposed to linden (HPV linden; n = 5), HPV+ (HPV water; n = 5), HPV- exposed to linden (WT linden; n = 5) and HPV- (WT water; n = 7). The linden (Tilia platyphyllos Scop.) extract was orally administered at a dose of 4.5 mg/10 mL per animal (dissolved in water) and changed daily for 33 days. The hydroethanolic extract of T. platyphyllos consisted of protocatechuic acid and (-)-epicatechin as the most abundant phenolic acid and flavonoid, respectively, and was found to be stable during the studied period. In two male groups a significant positive weight gain was observed but without association with the linden extract. Histological, biochemical, and oxidative stress analyses for the evaluation of kidney and liver damage support the hypothesis that the linden extract is safe and well-tolerated under the present experimental conditions. Skin histopathology does not demonstrate the chemopreventive effect of the linden extract against HPV16-induced lesions. The linden extract has revealed a favourable toxicological profile; however, additional studies are required to determine the chemopreventive potential of the linden extract. This journal is
- Obtenção otimizada de extratos bioativos de casca de marmelo: uma fonte alternativa de conservantes naturaisPublication . Pereira, Alexis; Añibarro-Ortega, Mikel; Cirić, Ana; Soković, Marina; Nogueira, António José M.; Pinela, José; Barros, LillianO marmelo (Cydonia oblonga M.) é um fruto amargo e adstringente utilizado sobretudo na produção de marmelada e outros produtos alimentares açucarados. De acordo com a Legislação Portuguesa [1], a marmelada é uma mistura homogénea e consistente obtida exclusivamente da cozedura do mesocarpo do marmelo com açúcares. Portanto, a produção industrial de marmelada implica o descarte da casca como um subproduto. No entanto, estudos anteriores indicam que a casca deste fruto possui compostos bioativos com propriedades antioxidantes e antimicrobianas e efeitos promotores de saúde [2-4]. Este estudo propõe assim a reinserção deste subproduto na cadeia de valor sob a forma de um conservante alimentar natural. Para otimização do processo de extração de compostos bioativos a partir desta matriz vegetal, foi implementado um desenho de composto central circunscrito de 20 pontos, combinando os efeitos dos fatores tempo (1–119 min), temperatura (25–94 °C) e proporção de etanol (0–100%). Como variáveis dependentes, foram considerados o rendimento das extrações, avaliado gravimetricamente, e os teores de compostos fenólicos e ácidos orgânicos, quantificados por HPLC-DAD-ESI/MSn e UFLC-PDA, respetivamente [5]. Estas análises permitiram identificar vários compostos fenólicos, incluindo ácidos fenólicos, flavan-3-óis e flavonóis, e ácido málico, entre outras moléculas. Os dados quantitativos foram seguidamente ajustados a uma equação polinomial quadrática para obtenção de modelos teóricos, os quais foram validados estatisticamente e usados para determinar as condições ótimas de extração. Estas foram aplicadas experimentalmente e os extratos obtidos foram analisados quanto ao potencial conservante, através da avaliação da atividade antioxidante por ensaios in vitro e da atividade antimicrobiana por métodos de microdiluição [5]. Estes extratos apresentaram capacidade de inibir a peroxidação lipídica e de inibir o crescimento de fungos e bactérias associadas a contaminações alimentares, destacando-se em alguns aspetos comparativamente com aditivos alimentares usados como controlo positivo. Estes resultados destacam o potencial inexplorado da casca de marmelo para obtenção de extratos bioativos ricos em compostos fenólicos e ácido málico, os quais poderão ser usados pela indústria alimentar para incorporação em alimentos e bebidas.