Percorrer por autor "Silva-Reis, Rita"
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- Exploring the Chemopreventive and Antioxidant Effects of Spearmint Leaf Hydroethanolic Extract in HPV16-transgenic MicePublication . Jesus, Tiago M.; Azevedo, Tiago; Silva-Reis, Rita; Ferreira, Tiago; Nascimento-Gonçalves, Elisabete; Medeiros, Catarina; Ferreira, João; Gama, Adelina; Gaivão, Isabel; Pires, Maria João; Lanzarin, Germano; Félix, Luís; Venância, Carlos; Medeiros, Rui; Bastos, Margarida M.S.M.; Finimundy, Tiane C.; Barros, Lillian; Costa, Rui M. Gil da; Oliveira, Paula A.Human papillomavirus (HPV) is the most common sexually transmitted infectious agent and, in cases of persistent infection, may cause cancer. This study evaluated the toxicological and antitumor properties of Mentha spicata extract (MSE) in KP14HPV16 mice, which carry HPV16 oncogenes. Thirty‑three female FVB/n mice (Mus musculus), including 17 HPV‑transgenic and 16 wild‑type (WT) mice, were divided into six groups. The control groups received tap water (WT‑C, n=5, and HPV‑C, n=6), while the treatment groups received either 0.50 mg/ml MSE (WT‑50 and HPV‑50, n=6) or 0.55 mg/ml MSE (WT‑55 and HPV‑55, n=5) in drinking water for 28 days. Afterwards, animals were sacrificed, and blood and organs were collected for histopathological and biochemical analysis. The main phenolic compounds in MSE were rosmarinic acid and luteolin‑O‑glucoronide. MSE did not significantly affect weight gain in WT mice; however, WT‑55 gained significantly more weight than HPV‑55. MSE demonstrated antioxidant activity as indicated by the modulation of hepatic superoxide dismutase and glutathione S‑transferase (GST) activity, as well as renal GST activity, in MSE‑treated HPV groups. MSE did not reduce histological lesion incidence or systemic inflammation in HPV16‑transgenic mice. In general, while MSE was safe and exhibited antioxidant activity, it did not significantly impact HPV16‑induced lesions, warranting further research to assess systemic effects with different concentrations and durations.
- Ganoderma Lucidum effects in an animal model of obesityPublication . Castro-Ribeiro, Catarina; Silva-Reis, Rita; Mendes-Gonçalves, Mariana; Ferreira, Tiago; Taofiq, Oludemi; Barros, Lillian; Martins, Tânia; Faustino-Rocha, Ana; Pires, Maria João; Pinto, M.L.; Ferreira, Isabel C.F.R.; Venâncio, Carlos; Rosa, Eduardo; Oliveira, Paula A.Obesity is a pandemic disease, and its evolution can be influenced by regular consumption of natural bioactive compounds. Mushrooms, such as Ganoderma lucidum (GL), include a wide variety of biomolecules with potential anti-obesity effects. This work aimed to study the influence of GL in an animal model of obesity. Forty-eight male mice (C57BL/6J) were divided into 5 groups: Group (G)-1-Western Control Diet; G-2-Western Diet 0.2% Cholesterol (WDC); G-3-WDC+0.7g/kg of GL; G-4-WDC+1.4g/ kg of GL; G-5 WDC+2.8g/kg of GL. Water and food consumption were recorded weekly. Animals were weighed individually, and their temperature was measured on the back and abdomen (thermographic camera FLIRE6390). Thirteen weeks later, animals were sacrificed, and organs collected. A liver portion was used for histopathology analysis (ethical approval nº 8776). Chemical characterization of the GL extract was profiled by HPLC-DAD-ESI/MS. Ganoderic acid H and p-hydroxybenzoic acid were the main triterpenic and phenolic acids in the extract, respectively. Food and water consumption were no different among groups. All animals showed weight gain (11-16%): animals without GL supplementation showed the highest weight gain (G2 and G1, respectively); the groups with GL showed the lowest weight gain, which decreased as the mushroom concentration increased. Basal and final body temperatures remained constant. Liver weight was different among groups (p<0.05). Microvesicular (39/47; 83%) and macrovesicular fatty changes (steatosis) were the most frequent morphological changes in the liver. Hyperlipidemic diets consumption promoted weight gain and obesity. The higher weight gain in the groups not supplemented with GL suggested its anti-obesity properties. In this study, animals developed steatosis, which was not modified by GL supplementation. However, it should be noticed that the changes in lipid metabolism are reversible, and the differences observed in the liver relative weights, lower in the groups supplemented with GL, suggested an ongoing process of restoring to normal hepatocyte’s phenotype.
- Ganoderma lucidum in an animal model of obesity: preliminary resultsPublication . Martins, Tiago; Castro-Ribeiro, Catarina; Silva-Reis, Rita; Mendes-Gonçalves, Mariana; Taofiq, Oludemi; Barros, Lillian; Pires, Maria João; Pinto, M.L.; Ferreira, Isabel C.F.R.; Venâncio, Carlos; Rosa, Eduardo; Oliveira, Paula A.Obesity is an emerging health problem worldwide. Hypercaloric or hyperlipidemic diets have been used as models of obesity induction in laboratory animals. Obesity can be influenced by regular consumption of natural bioactive compounds. Mushrooms, such as Ganoderma lucidum (GL), have been used in the human diet since ancient times and include a wide variety of biomolecules with medicinal properties. The main objective of this work was to study the effects of G. lucidum in an animal model of obesity.
- Lee Index variation and glucose clearance rate in an animal model of obesity with animals supplemented with Ganodema lucidumPublication . Castro-Ribeiro, Catarina; Silva-Reis, Rita; Mendes-Gonçalves, Mariana; Taofiq, Oludemi; Barros, Lillian; Martins, Tânia; Pires, Maria João; Pinto, M.L.; Ferreira, Isabel C.F.R.; Rosa, Eduardo; Oliveira, Paula A.The consumption of diets high in sugars and saturated fat are associated with obesity and other comorbidities, as well as glucose intolerance1. Obesity can be influenced by the regular consumption of natural bioactive compounds like those found in Ganoderma lucidum mushroom (GL)2. The main objective of this work is to determine body mass variations (Lee Index) and serum glucose levels in animals fed with diets supplemented with three concentrations of an hydroethanolic extract of GL. The fruiting bodies of GL were provided by Bioreishi- Agricultura Bioliogica, Lda. Forty-eight male mice (C57BL/6) were acquired and divided into 5 groups: G1-Western Diet 0.2% Cholesterol (WD); G2-Western Control (WC); G3-WD+0.7%g/kg of G. lucidum; G4-WD+1.4%g/kg of G. lucidum; G5- WD+2.8%g/kg of G. lucidum. At 7th and 13th weeks of study, the animals were measured (nasoanal distance in cm) in order to calculate the Lee Index (cubicle root of the weight (g)/the nasoanal length (cm) x 1000). Obesity was defined by a Lee index>310. Glucose intolerance test was performed on 4 animals in each group. The animals were fasted overnight and in the early morning, a 50% glucose solution (2g/kg) was injected intraperitoneally. Blood samples were collected one hour before glucose (time zero) administration and 30, 60 and 120 minutes later. Serum glucose was determined with the OGCare equipment. Glucose concentration values at time zero were considered control values. All ethical issues were followed (approval nº 8776). The chemical composition of the extract was profiled by HPLC-DAD-ESI/MS. All data were analyzed using the GraphPad Prism® for Windows software (version 7.0). Ganoderic acid H and p-hydroxybenzoic acid were the main triterpenic and phenolic acids found in the extract, respectively. In respect to the Lee index, the values show that all animals in the experimental groups became obese. In both weeks, G5 showed the highest values (353.45 ± 12.43 and 351.77 ± 12.24 respectively). At week 7, G1 and G2 differed statistically (p<0,05) from G5. Although G1 and G2 have the lowest Lee values in both weeks, they are the only ones that increase from week 7 to week 13, in contrast to the groups supplemented with GL. Regarding the glucose intolerance test, recorded glucose values at 30 minutes after the injection were increased in all groups, returning to normal values two hours later. At 13th week, the glucose values were increased in all groups in the 30 and 60 minutes after the intraperitoneal injection. At the end of two hours, the values decreased, but did not return to normal values in all the groups. Although animals in all experimental groups remained obese, animals supplemented with GL decreased their Lee Index. At 7th week the animals showed a normal glucose clearance, but in the last week of the study glucose values did not return to the values initially recorded after two hours, showing that the animals were not able to maintain the glucose clearance rate.
- Supplementation of an anthocyanin-rich elderberry (Sambucus nigra L.) extract in FVB/n mice: a healthier alternative to synthetic colorantsPublication . Azevedo, Tiago; Ferreira, Tiago; Ferreira, João Miguel Mendes; Teixeira, Filipa; Ferreira, Diana; Silva-Reis, Rita; Neuparth, Maria João; Pires, Maria João; Pinto, Maria de Lurdes; Costa, Rui Miguel Gil; Bastos, Margarida M.S.M.; Medeiros, Rui; Felix, Luis; Venâncio, Carlos; Dias, Maria Inês; Gaivão, Isabel; Barros, Lillian; Oliveira, Paula A.Featured Application Due to anthocyanins' potential as colorants, this anthocyanin-rich elderberry extract presents a healthier alternative to commercially available colorants and has the potential to be used at industry level. Sambucus nigra L., popularly known as elderberry, is renowned for its amazing therapeutic properties, as well as its uses as a food source, in nutraceuticals, and in traditional medicine. This study's aim was to investigate the effects of an elderberry extract (EE) on mice for 29 days, as well as the safety of the extract when used as a natural colorant. Twenty-four FVB/n female mice (n = 6) were randomly assigned to one of four groups: control, 12 mg/mL EE (EE12), 24 mg/mL EE (EE24), or 48 mg/mL EE (EE48). The predominant anthocyanins detected were cyanidin-3-O-sambubioside and cyanidin-3-O-glucoside. Food and drink intake were similar between groups, with the exception of EE48, who drank significantly less compared with the Control. Biochemical analysis of the liver showed that the changes observed in histological analysis had no pathological significance. The EE, at doses of 24 and 48 mg/mL, significantly reduced the oxidative DNA damage compared with the non-supplemented group. The S. nigra extract showed a favorable toxicological profile, affording it potential to be used in the food industry.
- The anti-tumour effect of spearmint (Mentha spicata) in a HPV-16-transgenic mouse modelPublication . Jesus, T.M.; Silva-Reis, Rita; Pires, Maria João; Lanzarin, Germano; Félix, Luís; Venâncio, Carlos; Costa, Rui Miguel Gil; Bastos, Margarida M.S.M.; Medeiros, Rui; Nogueira, António José M.; Barros, Lillian; Ferreira, Isabel C.F.R.; Rosa, Eduardo; Oliveira, Paula A.Infection by Human Papillomavirus (HPV) is the main cause of cervical cancer, highlighting the importance of studying compounds that may reduce viral activity and its lesions/symptoms. The aromatic herb spearmint (Mentha spicata) (MS) has proven anti-tumour properties 1. Thus, this study aimed to evaluate the effects of an hydroethanolic extract obtained from spearmint in HPV16-transgenic (HPV+/-) mice. The extract was obtained through maceration with ethanol/water (80:20, v/v), and the phenolic composition was determined through HPLC-DAD-ESI/MS. A total of thirteen compounds were identified in the hydroethanolic extract, being salvianolic acid B, rosmarinic acid and luteolin-7-O-glucuronide, the main compounds found. Moreover, the compounds revealed to be stable in the drinking water during the 5 tested days. Results show that HPV+/- (GIV, V and VI) have lower weight but higher water and food intake, as expected. Analysis of HPV+/- mice GIV showed a significant increase of superoxide dismutase activity when compared with GV (p=0.0029) and VI (p=0.0011). This suggests that group IV was subjected to a higher oxidative stress, as expected1. These results could also mean that MS is responsible for a decrease in the oxidative stress known to be induced by HPV, which in turn decreases SOD, further the role of MS as an antioxidant. Regarding genetic damage, no statistically significant changes between groups were found in the comet and micronucleus assays, implying that spearmint has no influence on genotoxicity at the concentrations employed. There were no significant differences concerning basal DNA damage between WT and transgenic individuals as seen in other studies 2. Further studies are required to clarify the antioxidant and antigenotoxic effects of spearmint.
- The anti-tumour effect of spearmint (Mentha spicata) in a HPV-16-transgenic mouse modelPublication . Jesus, T.M.; Silva-Reis, Rita; Pires, Maria João; Lanzarin, Germano; Félix, Luís; Venâncio, Carlos; Costa, Rui Miguel Gil; Bastos, Margarida M.S.M.; Medeiros, Rui; Nogueira, António José M.; Barros, Lillian; Ferreira, Isabel C.F.R.; Rosa, Eduardo; Oliveira, Paula A.Infection by Human Papillomavirus (HPV) is the main cause of cervical cancer, highlighting the importance of studying compounds that may reduce viral activity and its lesions/symptoms. The aromatic herb spearmint (Mentha spicata) (MS) has proven anti-tumor properties [1]. Thus, this study aimed to evaluate the effects of an hydroethanolic extract obtained from spearmint in HPV16-transgenic (HPV+/-) mice. The extract was obtained through maceration with ethanol/water (80:20, v/v), and the phenolic composition was determined through HPLC-DAD-ESI/MS. Thirty-three female mice (16 HPV-/- and 17 HPV+/-) were randomly divided into six groups: Group (G) I – HPV-/- w/o Mentha (n=5); G II – HPV-/- w/ Mentha (0.5 mg/ml; n=6); G III – HPV-/- w/ Mentha (0.55 mg/ml; n=5); G IV – HPV+/- w/o Mentha (n=6); G V – HPV+/- w/ Mentha (0.5 mg/ml; n=6); G VI – HPV+/- w/ Mentha (0.55 mg/ml; n=5). The spearmint extract was administered in the animal’s drinking water for 28 days. During the study, water and food intake as well the animals’ weights were recorded weekly. Afterwards, the animals were sacrificed, and their organs were collected for oxidative stress and genetic damage analysis. A total of thirteen compounds were identified in the hydroethanolic extract, being salvianolic acid B, rosmarinic acid and luteolin-7-O-glucuronide, the main compounds found. Moreover, the compounds revealed to be stable in the drinking water during the 5 tested days. Results show that HPV+/- (GIV, V and VI) have lower weight but higher water and food intake, as expected. Analysis of HPV+/- mice GIV showed a significant increase of superoxide dismutase activity when compared with GV (p=0.0029) and VI (p=0.0011). This suggests that group IV was subjected to a higher oxidative stress, as expected. These results could also mean that MS is responsible for a decrease in the oxidative stress known to be induced by HPV, which in turn decreases SOD, further the role of MS as an antioxidant. Regarding genetic damage, no statistically significant changes between groups were found in the comet and micronucleus assays, implying that spearmint has no influence on genotoxicity at the concentrations employed. There were no significant differences concerning basal DNA damage between WT and transgenic individuals as seen in other studies [2]. Further studies are required to clarify the antioxidant and antigenotoxic effects of spearmint.