Browsing by Author "Cruz, Maria T."
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- Antioxidant and anti-inflammatory activities of cytisus multiflorusPublication . Saraiva, Susana C.; Pereira, Olívia R.; Liberal, Joana; Batista, Maria T.; Domingues, Maria R.M.; Cruz, Maria T.; Cardoso, Susana M.Cytisus multiflorus(white spanish broom) is a plant used in folk medicine in the Iberian Peninsula, where it is claimed to have various health benefits. However, the usage is totally based on the available ethnopharmacological information, as no scientific data regarding its biological effects has been delivered. In this sense, is the aim of this work to contribute to the scientific knowledge of the antioxidant and anti-inflammatory properties of C. multiflorus. The extract was rich in phenolic compounds mainly chrysin-7-O-glycopyranoside and a dihydroxyflavone isomer of chrysin which accounted for 49.4±7.3 mg/g and 21.8±3.8 mg/g, respectively. The low EC50 values, determined by DPPH and reducing power assays, indicated that the C. multiflorus purified ethanolic extract has a high antioxidant capacity. Moreover, the extract did not cause cytotoxicity against RAW 264.7 macrophages for high concentrations and the treatment of this cell line with purified extract induced a significant decrease in the levels of NO. Overall, the gathered data suggests that C. multiflorus is in fact a good antioxidant and anti-inflammatory plant, as believed by the folk knowledge.
- Cytisus multiflorus and eriocephalus africanus as source of antioxidants and anti-inflammatory compoundsPublication . Saraiva, Susana C.; Pereira, Olívia R.; Liberal, Joana; Catarino, Marcelo D.; Batista, Maria T.; Cruz, Maria T.; Cardoso, Susana M.Historically, extracts and preparations of plants are the basis of traditional medicine and the starting point for the discovery of new therapeutic agents. Cytisus multiflorus and Eriocephalus africanus are small shrubs native from Iberian Peninsula and South Africa, respectively, and distributed in Mediterranean region. Despite their common application in folk medicine and claimed health benefits, including antioxidant and anti-inflammatory properties, there is still a lack of scientific data supporting this. In this work, phenolic-enriched extracts of Cytisus multiflorus and Eriocephalus africanus were obtained and evaluated in chemical models for their phenolic content, antioxidant capacities and their role in inflammatory process. Overall, the results from the chemical tests indicated that Cytisus multiflorus extract was more promising regarding antioxidant and anti-inflammatory properties reason why this extract was then further tested for these activities in biological models. The present communication will focus on the experimental data obtained so far by our group for the phenolic-enriched extracts of Cytisus multiflorus and Eriocephalus africanus, as a valid contribution to clarify the mechanisms of action of the claimed antioxidant and anti-inflammatory activities of the two plants.
- Estrutura e atividade imunoestimuladora dos polissacarídeos presentes em extratos aquosos de inflorescências secas de P. tridentatumPublication . Martins, Vitor Manuel Ramalheira; Cruz, Maria T.; Ferreira, Isabel; Coimbra, Manuel A.As inflorescências secas da carqueja (P. tridentatum L.) são utilizadas na preparação de extratos aquosos que, de acordo com a tradição popular, possuem propriedades terapêuticas. Durante a preparação dos extratos ocorre a extração de compostos bioativos, tais como polissacarídeos. O presente trabalho pretende determinar o tipo de polissacarídeos presente nos extraías e avaliar o seu possível contributo para as respetivas propriedades terapêuticas. Procedeu- se à extração, caracterização estrutural e avaliação da atívidade imunoestimuladora dos polissacarídeos presentes nos extratos. Foi detetada uma mistura de polissacarídeos, nomeadamente polissacarídeos pécticos, arabinogalactanas do Tipo-I e II, galactomananas e xiloglucanas, que apresenta atividade imunoestimuladora em macrófagos e que poderá contribuir para as propriedades terapêuticas atribuídas pela medicina popular a estes extratos.
- Immunostimulatory polysaccharides from the hot water extracts of prickled broom (P. tridentatum (L.) Willk) dried inflorescencesPublication . Martins, Vitor Manuel Ramalheira; Simões, Joana; Ferreira, Isabel; Cruz, Maria T.; Domingues, Maria R.M.; Coimbra, Manuel A.The decoctions of prickled broom (Pterospartum trídentatum (L.) Willk.) dried inflorescences have claimed beneficial properties for various health disorders [1, 2]. These can be assigned to several constituents, among them, the polysacharides. In order to unveil the contribution of the polysacharides and their structural features to the modulation of the innate immune activity, the hot water extracts from P. tridentatum dried inflorescences were prepared and fractionated by ethanol precipitation and anion exchange chromatography. A fraction that mainly contained pectic polysaccharides and acetylated galactomannans was isolated. This fraction evidenced in vitro immunostimulatory activity without compromising cellular viability, as evidenced by the increase registered in the nitric oxide (NO) production by macrophages. This activity decreased 60-75% after saponification, confirming that acetylation is an important structural feature for this biological property. In addition, the treatment of pectic polysaccharides with endo-polygalacturonase showed that type-1 and type-11 arabinogalactans, as well as low molecular weight galacturonans and xyloglucans, may also contribute to macrophage NO production. Thus, the polysaccharides present in the dried inflorescences of P. trídentatum may contribute to the health beneficial properties frequently attributed to the decoctions of this plant.
- In vitro macrophage nitric oxide production by Pterospartum tridentatum (L.) Willk. inflorescence polysaccharidesPublication . Martins, Vitor Manuel Ramalheira; Simões, Joana A.; Ferreira, Isabel C.F.R.; Cruz, Maria T.; Domingues, Maria R.M.; Coimbra, Manuel A.Pterospartum tridentatum (L.) Willk. decoctions of dried inflorescences are used in Portugal due to their claimed beneficial properties for various health disorders. To disclose the potential contribution of its polysaccharides to health benefits, in this work, hot water extracts from P. tridentatum inflorescences were prepared and fractionated by ethanol precipitation and anion exchange chromatography. The fraction rich in acetylated galactomannans evidenced an increase in nitric oxide (NO) production by macrophages. This activity decreased 60–75% after saponification, confirming that acetylation is an important structural feature for this biological property. In addition, the treatment of pectic polysaccharides with endo-polygalacturonase showed that type-I and type-II arabinogalactans, as well as low molecular weight galacturonans and xyloglucans, may also contribute to macrophage NO production. Thus, the polysaccharides present in P. tridentatum dried inflorescences may contribute to the health beneficial properties frequently attributed to the decoctions of this plant.
- Is cytisus multiflorus an antiinflamatory plant?Publication . Saraiva, Susana C.; Pereira, Olívia R.; Liberal, Joana; Batista, Maria T.; Cruz, Maria T.; Cardoso, Susana M.Cytisus multiflorus is a leguminous shrub native from Iberian Peninsula that is distributed in the south-west Mediterranean region. This plant is used in folk medicine and it is claimed to have various health benefits, including anti-inflammatory properties[1]. Yet, the anti-inflammatory usage of C. multiflorus is totally based on the available ethnopharmacological information while no scientific data on this capacity and on molecular targets has been reported for the plant. Hence, the present work aims to clarify the possible anti-inflammatory mechanisms of C. multiflorus. A purified ethanolic extract was prepared and its high antioxidant capacity was confirmed though the DPPH radical scavenging [2] and reducing power [3] assays (EC50 values 13.4±1.0 and 11.4±2.1 μg/mL, respectively). Moreover, anti-inflammatory properties of the C. multiflorus extract were tested on a lipopolysaccharide-stimulated Raw 264.7 macrophages model. In order to accomplish that, nitric oxide (NO) production, scavenging activity and cytotoxicity of the extract were assessed. Furthermore, the effects on two proteins that are potential targets to prevent or treat chronic inflammation, namely cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS), were estimated by Western Blot analysis. The obtained results showed that C. multiflorus extract was able to significantly inhibit the production of NO for non-toxic concentrations. The treatment of this cell line with 161 µg/mL and 325 µg/mL of the purified extract induced a decrease in the levels of NO of 24% and 32%, respectively. Furthermore, despite no changes on COX-2 levels were observed, iNOS expression was significantly diminished by the treatment with the highest concentration of the extract. Overall, the present results suggest that C. multiflorus actually exerts an anti-inflammatory action which is, at least partially, mediated through the inhibition of iNOS expression.
- Is Cytisus multiflorus an antiinflamatory plant?Publication . Saraiva, Susana C.; Pereira, Olívia R.; Liberal, Joana; Batista, Maria T.; Cruz, Maria T.; Cardoso, Susana M.Cytisus multiflorus is a leguminous shrub native from Iberian Peninsula that is distributed in the south-west Mediterranean region. This plant is used in folk medicine and it is claimed to have various health benefits, including anti-inflammatory properties[1]. Yet, the anti-inflammatory usage of C. multiflorus is totally based on the available ethnopharmacological information while no scientific data on this capacity and on molecular targets has been reported for the plant. Hence, the present work aims to clarify the possible anti-inflammatory mechanisms of C. multiflorus. A purified ethanolic extract was prepared and its high antioxidant capacity was confirmed though the DPPH radical scavenging [2] and reducing power [3] assays (EC50 values 13.4±1.0 and 11.4±2.1 μg/mL, respectively). Moreover, anti-inflammatory properties of the C. multiflorus extract were tested on a lipopolysaccharide-stimulated Raw 264.7 macrophages model. In order to accomplish that, nitric oxide (NO) production, scavenging activity and cytotoxicity of the extract were assessed. Furthermore, the effects on two proteins that are potential targets to prevent or treat chronic inflammation, namely cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS), were estimated by Western Blot analysis. The obtained results showed that C. multiflorus extract was able to significantly inhibit the production of NO for non-toxic concentrations. The treatment of this cell line with 161 µg/mL and 325 µg/mL of the purified extract induced a decrease in the levels of NO of 24% and 32%, respectively. Furthermore, despite no changes on COX-2 levels were observed, iNOS expression was significantly diminished by the treatment with the highest concentration of the extract. Overall, the present results suggest that C. multiflorus actually exerts an anti-inflammatory action which is, at least partially, mediated through the inhibition of iNOS expression.
- Isolation and characterization of polysaccharides from Fraxinus angustifolia infusionsPublication . Martins, Vitor Manuel Ramalheira; Francisco, Vera; Cruz, Maria T.; Coimbra, Manuel A.In folk medicine there is a great variety of plants that are used for as infusions, such as Camellia sinensis and Matricaria recutita. Despite the reported biological activities and health benefits of these infusions, most of the knowledge achieved so far is based on folk tradition passed over several generations, without a sound scientific basis. In Trás-os-Montes region, the dried leaves of the narrow-leafed ash “freixo” (Fraxinus angustifolia) are used for medicinal purposes, particularly against high levels of cholesterol, blood pressure and uric acid. These health benefits are associated with the presence of biologically active compounds such as phenolic compounds, essential oils, and polysaccharides, among others. Although phenolic compounds and essential oils have been studied in detail for more than two decades, the structures of the polysaccharides present in plant infusions and their involvement in the health benefits is still incipient. Therefore, in this work we present a study regarding the structure of the polysaccharides present in the infusions of “freixo” dried leaves. “Freixo” leaves were collected and dried according to the popular tradition and used for the preparation of the infusions. The polysaccharides were recovered by dialysis, fractionated by ethanol precipitation and anion exchange chromatography, yielding fractions with distinct ethanol solubility and uronic acid content. Sugar and linkage analysis evidenced the presence of pectic polysaccharides, frequently reported as immunostimulatory active. The assessment of the biological activity of these fractions is in progress.
- NO radical scavenging and iNOS expression inhibition by cytisus multiflorusPublication . Saraiva, Susana C.; Pereira, Olívia R.; Liberal, Joana; Batista, Maria T.; Cruz, Maria T.; Cardoso, Susana M.Historically, extracts and preparations of plants are the basis of traditional medicine and the starting point for the discovery of new therapeutic agents. Cytisus multiflorus is used in folk medicine and it is claimed to have various health benefits, including anti-inflammatory properties. Still, no scientific data regarding this ability has been described for this plant. The present work aims to clarify the antioxidant capacity and the anti-inflammatory mechanisms of Cytisus multiflorus. A purified ethanolic extract was prepared and its antioxidant abilities were evaluated through the DPPH scavenging and reducing power assays. Anti-inflammatory properties were assessed by determining the amounts of nitric oxide (NO) on a chemical and on lipopolysaccharide-stimulated Raw 264.7 macrophages models. Furthermore, the effects on two proteins that are potential targets to prevent or treat chronic inflammation, namely cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS), were also estimated in the cellular model by Western Blot analysis. The ethanolic extract showed high antioxidant capacity, with EC50 values of 13.4±1.0 and 11.4±2.1 μg/mL for DPPH and reducing power assays, respectively. It also efficiently scavenged the NO radical and inhibited the NO production, in the chemical and cellular models, respectively. Furthermore, despite no changes on intracellular COX-2 levels were observed, iNOS expression was significantly diminished by the treatment with non-toxic concentrations of Cytisus multiflorus ethanolic extract. The present results suggest that Cytisus multiflorus is a good antioxidant and that it actually exerts an anti-inflammatory action.
- NO radical scavenging and iNOS expression inhibition by Cytisus multiflorusPublication . Saraiva, Susana C.; Pereira, Olívia R.; Liberal, Joana; Batista, Maria T.; Cruz, Maria T.; Cardoso, Susana M.Historically, extracts and preparations of plants are the basis of traditional medicine and the starting point for the discovery of new therapeutic agents. Cytisus multiflorus is used in folk medicine and it is claimed to have various health benefits, including anti-inflammatory properties. Still, no scientific data regarding this ability has been described for this plant. The present work aims to clarify the antioxidant capacity and the anti-inflammatory mechanisms of Cytisus multiflorus. A purified ethanolic extract was prepared and its antioxidant abilities were evaluated through the DPPH scavenging and reducing power assays. Anti-inflammatory properties were assessed by determining the amounts of nitric oxide (NO) on a chemical and on lipopolysaccharide-stimulated Raw 264.7 macrophages models. Furthermore, the effects on two proteins that are potential targets to prevent or treat chronic inflammation, namely cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS), were also estimated in the cellular model by Western Blot analysis. The ethanolic extract showed high antioxidant capacity, with EC50 values of 13.4±1.0 and 11.4±2.1 μg/mL for DPPH and reducing power assays, respectively. It also efficiently scavenged the NO radical and inhibited the NO production, in the chemical and cellular models, respectively. Furthermore, despite no changes on intracellular COX-2 levels were observed, iNOS expression was significantly diminished by the treatment with non-toxic concentrations of Cytisus multiflorus ethanolic extract. The present results suggest that Cytisus multiflorus is a good antioxidant and that it actually exerts an anti-inflammatory action.