Browsing by Author "Medeiros-Fonseca, Beatriz"
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- Aloysia citrodora extract as a chemopreventive agent against HPV16-induced lesions: findings from K14-HPV16 micePublication . Medeiros-Fonseca, Beatriz; Faustino-Rocha, Ana; Silva, Jessica; Silva, Mónica; Pires, Maria João; Neuparth, Maria João; Vala, Helena; Vasconcelos-Nóbrega, Cármen; Dias, Maria Inês; Barros, Lillian; Gonçalves, Lio; Gaivão, Isabel; Bastos, Margarida M.S.M.; Félix, Luís; Venâncio, Carlos; Medeiros, Rui; Costa, Rui Miguel Gil; Oliveira, Paula A.Aloysia citrodora has a long history of traditional use in treating various ailments. This study evaluated the in vivo chemopreventive efficacy and systemic toxicity of an extract of A. citrodora in a transgenic mouse model of HPV16 (human papillomavirus type 16)-induced cancer. Methods: The experiment involved six groups (n = 5): group 1 (G1, wild-type (WT), water), group 2 (G2, HPV, water), group 3 (G3, WT, 0.013 g/mL), group 4 (G4, HPV, 0.006 g/mL), group 5 (G5, HPV, 0.008 g/mL), and group 6 (G6, HPV, 0.013 g/mL). Throughout the assay, humane endpoints, body weight, food, and water consumption were recorded weekly. The internal organs and skin of the mice were collected for analysis after they were sacrificed. Toxicological parameters that were studied included hematological and biochemical blood markers, splenic and hepatic histology, and hepatic oxidative stress. Results: A. citrodora extract seems to reduce the incidence of dysplastic and in situ carcinoma skin lesions induced by HPV16 in this model, suggesting that dietary supplementation with concentrations of 0.008 g/mL and 0.013 g/mL may have beneficial chemopreventive effects. Conclusions: The extract did not induce any concentration-dependent toxicological effects on any of the parameters included in the study, indicating a favorable toxicological profile under these experimental conditions.
- Efeito da aplicação repetida de Cytinus hypocistis em murganhos transgénicos (K14HPV16): avaliação de humane endpointsPublication . Medeiros-Fonseca, Beatriz; Segurado, Olga; Costa, Diana; Medeiros, Catarina; Medeiros, Rui; Pires, Maria João; Bastos, Margarida M.S.M.; Silva, Ana Rita; Barros, Lillian; Ferreira, Isabel C.F.R.; Costa, Rui Miguel Gil; Oliveira, Paula A.Em, 1959 Russel e Burch propuseram os 3Rs (Reduce, Refine e Replacement) em experimentação animal e desde então as diversas entidades envolvidas na temática têm feito esforços conjuntos para os aplicar (1). Nesse sentido foi gradualmente introduzida a avaliação e registo dos humane endpoints (HE) dos animais durante procedimentos experimentais, para monitorizar o seu sofrimento e tomar decisões sobre a necessidade, ou não, de finalizar o ensaio antes da data prevista (2). Contudo, apesar das exigências legais, observa-se grande escassez de publicações sobre a avaliação de HE nos procedimentos com animais de laboratório. Assim, é nosso objetivo com este trabalho apresentar os HE durante a aplicação diária de um creme com Cytinus hypocistis numa estirpe de murganhos transgénicos.
- Effects of a Cyperus esculentus L. plant-based beverage on FVB/n female micePublication . Fernandes, Filipa Alexandra; Oliveira, Paula A.; Pinto, M.L.; Venâncio, Carlos; Félix, Luís; Medeiros-Fonseca, Beatriz; Correia, Rossana; Prieto Lage, Miguel A.; Ferreira, Isabel C.F.R.; Barros, Lillian; Heleno, Sandrina A.This work evaluated the effects of the consumption of a plant-based beverage (Cyperus esculentus L., Adansonia digitata L., and thermal water) on the physiological parameters of mice over a 28-day period. Thirty-two female FVB/n mice (n = 8) were randomly assigned to one of four groups divided into two experimental protocols: Group 1 drank water and Group 2 drank a plant-based beverage for 24 h; in the second experimental protocol, Group 3 consumed water and Group 4 consumed plant-based beverage for a limited time (4 h). Two experimental protocols were conducted to assess whether the exposure time to the beverage affects the animals’ physiological parameters, to determine if there is a possible daily limit for consumption of the product and to analyze their adverse effects. The mice consuming a beverage ingested a larger amount of drink and a smaller amount of food. Histologically there are no pathological changes in collected organs. The consumption of a plant-based beverage has been shown to have a positive effect on oxidative markers and can have a diuretic action. According to results, no behavioral changes or clinical signs of disease were observed throughout both experimental protocols, and no mortality was recorded.
- Exploring the therapeutic potential of Quercus ilex acorn extract in papillomavirus-induced lesionsPublication . Medeiros-Fonseca, Beatriz; Faustino-Rocha, Ana; Pires, Maria João; Neuparth, Maria João; Vala, Helena; Vasconcelos-Nóbrega, Cármen; Gouvinhas, Irene; Barros, Ana Novo; Dias, Maria Inês; Barros, Lillian; Bastos, Margarida M.S.M.; Gonçalves, Lio; Félix, Luís; Venâncio, Carlos; Medeiros, Rui; Costa, Rui Miguel Gil; Oliveira, Paula A.Papillomaviruses (PVs) infections have been documented in numerous animal species across different regions worldwide. They often exert significant impacts on animal health and livestock production. Scientists have studied natural products for over half a century due to their diverse chemical composition, acknowledging their value in fighting cancer. Acorns (Quercus ilex) are believed to have several unexplored pharmacological properties. This study aimed to evaluate the in vivo safety and cancer chemopreventive activity of an infusion extract of Q. ilex in a transgenic mouse model of human PV (HPV)-16, which developed squamous cell carcinomas through a multistep process driven by HPV16 oncogenes. Q. ilex extract was prepared by heating in water at 90°C and then characterized by mass spectrometry. Phenolic compounds from this extract were administered in drinking water to female mice in three different concentrations (0.03, 0.06, and 0.09 g/mL) over a period of 28 consecutive days. Six groups (n = 6) were formed for this study: group 1 (G1, wildtype [WT], water), group 2 (G2, HPV, water), group 3 (G3, WT, 0.09 g/mL), group 4 (G4, HPV, 0.03 g/mL), group 5 (G5, HPV, 0.06 g/ mL), and group 6 (G6, HPV, 0.09 g/mL). Throughout the experiment, humane endpoints, body weight, food intake, and water consumption were recorded weekly. Following the experimental period, all mice were sacrificed, and blood, internal organs, and skin samples were collected. Blood was used to measure glucose and microhematocrit and later biochemical parameters, such as creatinine, urea, albumin, alanine aminotransferase, and total proteins. Histological analysis was performed on skin and organ samples. The administration of Q. ilex extract resulted in a statistically significant increase in relative organ weight among HPV transgenic animals, indicating adaptive biological response to the tested concentrations. Moreover, a reduction in characteristic skin lesions was observed in animals treated with the 0.06 and 0.09 g/mL extract. These results provide a favorable chemopreventive profile for Q. ilex extract at concentrations of 0.06 and 0.09 g/mL. This study highlights the potential of Q. ilex extract as a safe and effective therapeutic strategy against HPV16- associated lesions in transgenic mouse models. The limitation of our study was the durability of transgenic animals. As a more sensitive species, we must always be careful with the durability of the test. We intend to study concentrations of 0.06 and 0.09 g/mL for longer to further investigate their possible effects.
- Laurus nobilis (laurel) aqueous leaf extract's toxicological and anti-tumor activities in HPV16-transgenic micePublication . Medeiros-Fonseca, Beatriz; Mestre, V.F.; Colaço, B.; Pires, Maria João; Martins, Tânia; Costa, Rui Miguel Gil; Neuparth, Maria João; Medeiros, Rui; Moutinho, Magda S.S.; Dias, Maria Inês; Barros, Lillian; Bastos, Margarida M.S.M.; Félix, Luís; Venâncio, Carlos; Ferreira, Isabel C.F.R.; Antunes, L.M.; Oliveira, Paula A.Cancers induced by human papillomavirus (HPV) infection remain a significant public health threat, fueling the study of new therapies. Laurel (Laurus nobilis) compounds and extracts recently showed in vitro activity against HPV-transformed cell lines. This work aims to evaluate the in vivo efficacy and hepatic toxicity of a laurel extract in a transgenic mouse model of HPV16-induced cancer. The extract was administered in drinking water (20 mg per animal per day) for three consecutive weeks, using four experimental groups (n = 10) (group I: HPV16−/− without treatment, group II: treated HPV16−/−, group III: HPV16+/− without treatment and group IV: treated HPV16+/−). Following the treatment period, animals were sacrificed and skin samples were used to classify skin lesions histologically. Toxicological parameters included hematological and biochemical blood markers, splenic and hepatic histology and hepatic oxidative stress. The extract did not prevent the progression of HPV16-induced cutaneous lesions in this model. The treated wildtype animals showed mild hepatitis, while transgenic animals suffered weight loss. However, there were no changes concerning hematological, biochemical and hepatic oxidative stress markers.