Browsing by Author "Gaspar, Maria Manuela"
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- Combination of hyaluronic acid and PLGA particles as hybrid systems for viscosupplementation in osteoarthritisPublication . Mota, Ana Henriques; Direito, Rosa; Carrasco, Marta P.; Rijo, Patricia; Ascensao, Lia; Viana, Ana Silveira; Rocha, Joao; Eduardo-Figueira, Maria; Rodrigues, Maria Joao; Custódio, Luísa; Kuplennik, Nataliya; Sosnik, Alejandro; Almeida, Antonio Jose; Gaspar, Maria Manuela; Reis, Catarina PintoHyaluronic acid (HA) is commonly used through intra-articular administration for viscosupplementation in osteoarthritis and other disorders. HA is generally supplied as an injection commonly reported as painful, with strong limitations after treatment. In this study, an alternative delivery system was constructed based on HA hydrogel and poly(lactic-co-glycolic acid) (PLGA) particles with oleic acid. Development studies included the determination of particle toxicity, hemolytic activity, in vitro and in vivo anti-inflammatory activity using macrophages and a murine model, respectively. This study showed that empty PLGA particles presented a mean size of 373 nm, while particles containing HA and oleic acid showed a marked particle size increase. The HA association efficiency was of 73.6% and 86.2% for PLGA particles without and with oleic acid, respectively. The in vitro HA release from PLGA particles revealed a sustained profile. Particles showed a good in vitro cell compatibility and the risk of hemolysis was less < 1%, ensuring their safety. The in vivo anti-inflammatory study showed a higher inhibition for HA-loaded PLGA particles when compared to HA solution (78% versus 60%) and they were not different from the positive control, clearly suggesting that this formulation may be a promising alternative to the current HA commercial dosage form.
- If you cannot beat them, join them: exploring the fruits of the invasive species Carpobrotus edulis (L.) NE Br as a source of bioactive productsPublication . Castañeda-Loaiza, Viana; Placines, Chloé; Rodrigues, Maria João; Pereira, Catarina; Zengin, Gokhan; Uysal, Ahmet; Jeko, Jozsef; Cziaky, Zoltan; Reis, Catarina Pinto; Gaspar, Maria Manuela; Custódio, LuísaThe halophyte species Carpobrotus edulis (L.) N.E. Br, also known as Hottentot-fig, is one of the 20 most aggressive invasive species of coastal areas worldwide. It is native to South Africa, where it is used in traditional medicine for the treatment of several diseases, including tuberculosis and acquired immunodeficiency syndrome (AIDS) caused by the human immunodeficiency virus (HIV). Aiming at a sustainable use of its biomass as a value-added product, this work reports for the first time the in vitro antioxidant, anti-microbial, enzymatic inhibitory properties and toxicity of peel and flesh extracts of Hottentot-fig mature fruits. The extracts' chemical composition was also determined by spectrophotometric methods (total contents of phenolics: TPC; flavonoids: TFC and tannins: TTC), and by high-performance liquid chromatography coupled with electrospray ionization mass spectrometry (HPLC-ESI-MS/MS). The peels' extracts had generally the highest TPC, TFC and TTC, especially the ethanol ones (TPC: 272.82 mg gallic acid equivalents (GAE)/g dry weight (DW), TFC: 1.58 mg quercetin equivalents (QE)/g DW and TTC: 20.3 mg catechin equivalents (CE)/g DW). The peels' extracts also had the highest diversity of compounds, mostly phenolic acids, flavonoids, and coumarins, as identified by HPLC-ESI-MS/MS. Some molecules were specific to a particular fruit part, for example, coumaric acid and uvaol in the peel, and vanillin and kaempferol-O-(rhamnosyl)hexosylhexoside in the flesh. Some compounds are here described for the first time in Hottentot-fig, such as azelaic acid and emodin. The peel's extracts had the highest anti radical activity, especially the ethanol and acetone towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) (half maximal inhibitory concentration (IC50) values of 0.59 and 0.88 mg/mL, respectively), and the acetone extract against 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) (IC50 = 0.56 mg/mL). Samples had nil capacity to chelate iron, a low copper chelation potential, but a significant capacity to reduce iron, especially the ethanol (IC50 = 0.09 mg/mL) and the acetone extracts of peels (IC50 = 0.10 mg/mL) and flesh (IC50 = 0.11 mg/mL) and also the water peel's extracts (IC50 = 0.18 mg/mL). Samples had nil to low activity towards the enzymes acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), alpha-amylase and alpha-glucosidase, but displayed a strong inhibition of tyrosinase, especially the ethanol peel's extracts (29.55 mg kojic acid equivalents (KAE)/g). Samples had nil to low in vitro toxicity towards human keratinocytes. All together our results suggests possible novel biotechnological applications of Hottentot-fig fruits as sources of innovative bioactive ingredients for the food, cosmetic, agriculture and/or pharmaceutical industries.
- Inhalable locust bean gum microparticles co-associating isoniazid and rifabutin: therapeutic assessment in a murine model of tuberculosis infectionPublication . Grenha, Ana; Alves, Ana D.; Guerreiro, Filipa; Pinho, Jacinta; Simões, Sandra; Almeida, António José; Gaspar, Maria ManuelaTuberculosis is a leading cause of death worldwide. Although the development of new antimycobacterial drugs is an obvious and necessary strategy to address the disease, improving the therapeutic performance of drugs already approved constitutes a valuable alternative approach. As the lung is the most affected organ, where M. tuberculosis is able to survive and proliferate, the direct pulmonary delivery of antitubercular drugs comprises a highly promising therapeutic strategy. In this work, spray-dried locust bean gum (LBG) microparticles were used to deliver a combination of two first line antitubercular drugs, isoniazid (INH) and rifabutin (RFB), to the alveolar zone, where macrophages hosting the bacteria reside. LBG is expected to mediate favoured macrophage uptake of microparticles, leading to enhanced therapeutic effect. The therapeutic effect of LBG/INH/RFB microparticles was evaluated in a murine model infected with M. tuberculosis, strain H37Rv and compared with oral co-therapy of INH and RFB in the free form. The pulmonary administration of LBG/INH/RFB microparticles 5 times per week was the only treatment schedule that provided negative growth index values in lung (-0.22), spleen (-0.14) and liver (-0.26) even using a lower therapeutic dose for both antibiotics. For the control group, the respective values were +1.95, +0.75 and +0.96.
- Locust bean gum (LBG) – a potential excipient for inhalation purposes: excipient characterisation and in vitro and in vivo toxicological evaluationPublication . Pontes, Jorge Filipe; Guerreiro, Filipa; da Silva, Joana Pinto; Almeida, Maria; Rosso, Annalisa; Rosa da Costa, Ana M; Agusti, Géraldine; Lollo, Giovanna; Gaspar, Maria Manuela; Grenha, AnaDry powders proposed for lung drug delivery typically involve excipients not approved for inhalation. The physicochemical characterisation of excipients is informative regarding their interaction with different body structures. Locust Bean Gum (LBG) has been proposed for diverse applications, including inhalation, benefiting from targeting ability towards phagocytic cells owing to the presence of mannose moieties. The aim of the present study was to characterise the physicochemical parameters of LBG and, for the first time, draw a toxicological profile for this excipient. LBG from three different suppliers was evaluated and eventual changes on polymer characteristics induced by purification and microparticle production were assessed, which were observed to not occur. The commercial samples showed identical FTIR spectra, as well as TGA and DSC profiles, Mw around 3.60 × 106 Da, and Tg near − 39 ◦C. All microparticles presented similar morphology and Feret diameters around 4 μm. In vitro assays performed on respiratory (A549) cells evidenced no impact of LBG microparticles on cell viability (> 80 %) when biorelevant concentrations (≈ 0.1 mg/mL) were used. Additionally, inhalation of LBG microparticles by mice provided indications of a safe profile, without induction of allergic reactions. The basis is laid for further exploration of this material in inhalation.
- A newfangled collagenase inhibitor topical formulation based on Ethosomes with Sambucus nigra L. ExtractPublication . Mota, Ana Henriques; Prazeres, Inês; Mestre, Henrique; Bento-Silva, Andreia; Rodrigues, Maria Joao; Duarte, Noélia; Serra, Ana Teresa; Bronze, Maria Rosário; Rijo, Patrícia; Gaspar, Maria Manuela; Viana, Ana Silveira; Ascensão, Lia; Pinto, Pedro; Kumar, Pradeep; Almeida, António José; Reis, Catarina PintoSambucus nigra L. (S. nigra) is a shrub widespread in Europe and western Asia, traditionally used in medicine, that has become popular in recent years as a potential source of a wide range of interesting bioactive compounds. The aim of the present work was to develop a topical S. nigra extract formulation based on ethosomes and thus to support its health claims with scientific evidence. S. nigra extract was prepared by an ultrasound-assisted method and then included in ethosomes. The ethosomes were analyzed in terms of their size, stability over time, morphology, entrapment capacity (EC), extract release profile, stability over time and several biological activities. The prepared ethosomes were indicated to be well defined, presenting sizes around 600 nm. The extract entrapment capacity in ethosomes was 73.9 ± 24.8%, with an interesting slow extract release profile over 24 h. The extract-loaded ethosomes presented collagenase inhibition activity and a very good skin compatibility after human application. This study demonstrates the potential use of S. nigra extract incorporated in ethosomes as a potential cosmeceutical ingredient and on further studies should be performed to better understand the impact of S. nigra compounds on skin care over the time.
- Respirable konjac glucomannan microparticles as antitubercular drug carriers: Effects of in vitro and in vivo interactionsPublication . Guerreiro, Filipa; Pontes, Jorge Filipe; Gaspar, Maria Manuela; Rosa Da Costa, Ana; Faleiro, Maria Leonor; Grenha, AnaPulmonary delivery of drugs is potentially beneficial in the context of lung disease, maximising drug concentrations in the site of action. A recent work proposed spray-dried konjac glucomannan (KGM) microparticles as antitubercular drug (isoniazid and rifabutin) carriers to treat pulmonary tuberculosis. The present work explores in vitro and in vivo effects of these microparticles, focusing on the ability for macrophage uptake, the exhibited antibacterial activity and safety issues. Efficient uptake of KGM microparticles by macrophages was demonstrated in vitro, while the antitubercular activity of the model drugs against Mycobacterium bovis was not affected by microencapsulation in KGM microparticles. Despite the good indications provided by the developed system, KGM is not yet approved for pulmonary applications, which is a limiting characteristic. To reinforce the available data on the performance of the material, safety parameters were evaluated both in vitro and in vivo, showing promising results. No significant cell toxicity was observed at concentrations considered realistic for lung delivery approaches (up to 125 & mu;g/mL) when lung epithelial cells and macrophages were exposed to KGM microparticles (both drug-loaded and unloaded). Finally, no signs of systemic or lung inflammatory response were detected in mice after receiving 10 administrations of unloaded KGM microparticles.
- Synchronous insight of in vitro and in vivo biological activities of Sambucus nigra L. extracts for industrial usesPublication . Mota, Ana Henriques; Andrade, Joana M.; Rodrigues, Maria Joao; Custódio, Luísa; Bronze, Maria Rosario; Duarte, Noelia; Baby, Andre; Rocha, Joao; Gaspar, Maria Manuela; Simoes, Sandra; Carvalheiro, Manuela; Fattal, Elias; Almeida, Antonio Jose; Reis, Catarina PintoThere is a re-emerging interest in natural products as reputable sources of new active pharmaceutical ingredients. This study synchronously reports in vitro, with more than one cell line, and in vivo biological activities of extracts obtained from Sambucus nigra. Using several solvents and techniques, eighteen extracts were obtained from fresh and dried berries, and fresh flowers. The flavonoid content and identification were determined using HPLC-MS/MS. The extracts were then screened for antioxidant activity, total polyphenol content, collagenase, elastase, tyrosinase and acetylcholinesterase inhibition as well as photoprotection. In vitro and in vivo (murine model) anti-inflammatory activity and cytotoxicity (skin and monocytic cells) were also studied. The most promising extracts were those obtained from fresh flowers using either ultrasounds or methanol. These extracts showed similar results to positive controls, particularly the antioxidant activity (74.5 +/- 1.6 %), collagenase inhibition (93.6 +/- 0.6 %), photoprotection (Sun Protection Factor > 50), in vitro anti-inflammatory activity (96.9 +/- 2.9 %), as well as oral/topical anti-inflammatory activity. The ultrasounds/ethanol extract of fresh flowers presented higher collagenase inhibition (88.3 +/- 2.8 %) and in vitro anti-inflammatory activity (101.8 +/- 1.5 %). Cytotoxicity testing confirmed the safety. Chemical characterization allowed the deduction of a correlation between extract composition and biological activities, suggesting a straightforward application in the development of novel products subject to further investigation.
- The aquaporin-3-inhibiting potential of polyoxotungstatesPublication . Pimpão, Catarina; da Silva, Inês V.; Mósca, Andreia F.; Pinho, Jacinta O.; Gaspar, Maria Manuela; Gumerova, Nadiia I.; Rompel, Annette; Aureliano, Manuel; Soveral, GraçaPolyoxometalates (POMs) are of increasing interest due to their proven anticancer activities. Aquaporins (AQPs) were found to be overexpressed in tumors bringing particular attention to their inhibitors as anticancer drugs. Herein, we report for the first time the ability of polyoxotungstates (POTs), such as of Wells-Dawson P2W18, P2W12, and P2W15, and Preyssler P5W30 structures, to affect aquaporin-3 (AQP3) activity and impair melanoma cell migration. The tested POTs were revealed to inhibit AQP3 function with different effects, with P2W18, P2W12, and P5W30 being the most potent (50% inhibitory concentration (IC50) = 0.8, 2.8, and 3.2 µM), and P2W15 being the weakest (IC50 > 100 µM). The selectivity of P2W18 toward AQP3 was confirmed in yeast cells transformed with human aquaglyceroporins. The effect of P2W12 and P2W18 on melanoma cells that highly express AQP3 revealed an impairment of cell migration between 55% and 65% after 24 h, indicating that the anticancer properties of these compounds may in part be due to the blockage of AQP3-mediated permeability. Altogether, our data revealed that P2W18 strongly affects AQP3 activity and cancer cell growth, unveiling its potential as an anticancer drug against tumors where AQP3 is highly expressed.