Browsing by Author "Oliveira, Patricia Capelari de"

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    Anti-inflammatory activity of Lychnophora passerina, Asteraceae (Brazilian Arnica).
    (2011) Oliveira, Patricia Capelari de; Paula, Carmem Aparecida de; Rezende, Simone Aparecida; Campos, Fernanda Torres; Guimarães, Andrea Grabe; Lombardi, Júlio Antônio; Guimarães, Dênia Antunes Saúde
    Ethnopharmacological relevance: Lychnophorapasserina (Asteraceae), popularly known as “arnica,” is used to treat inflammation, pain, rheumatism, contusions, bruises and insect bites in Brazilian traditional medicine. Materials and methods: The anti-inflammatoryactivity of crude ethanolic extract of aerial parts of L. passerina and its ethyl acetate and methanolic fractions had their abilities to modulate the production of NO, TNF-α and IL-10 inflammatory mediators in LPS/IFN-γ-stimulated J774.A1 macrophages evaluated. Moreover, the crude ethanolic extract and derived fractions were also in vivo assayed by carrageenan-induced paw oedema in mice. Results: In vitro assays showed remarkable anti-inflammatoryactivity of L. passerina crude ethanolic extract (EE) and its ethyl acetate (A) and methanolic (M) fractions, through the inhibition of production of NO and TNF-α inflammatory mediators and induction of production of IL-10 anti-inflammatory cytokine. In vivo assays showed anti-inflammatoryactivity for EE 10% ointment, similar to the standard drug diclofenac gel. The A and M fraction ointments 20% presented anti-inflammatoryactivity. Conclusion: The results obtained showed that possible anti-inflammatory effects of EE and its A and M fractions may be attributed to inhibition pro-inflammatory cytokines production, TNF-α and NO and to increased IL-10 production. EE, A and M ointments showed topical in vivoanti-inflammatoryactivity. The in vivoanti-inflammatoryactivity of EE of L. passerina may be related to synergistic effects of different substances in the crude extract. Therefore, traditional use of aerial parts of L. passerina in the inflammatory conditions could be beneficial to treat topical inflammatory conditions, as evidenced by the present study.
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    Estudo fitoquímico e avaliação da atividade antiinflamatória Lychnophora passerina (Mart ex DC) Gardn (Asteraceae).
    (Programa de Pós-Graduação em Ciências Farmacêuticas. CIPHARMA, Escola de Farmácia, Universidade Federal de Ouro Preto., 2010) Oliveira, Patricia Capelari de; Guimarães, Dênia Antunes Saúde
    O homem mantém relações de subsistência com a natureza desde tempos primordiais. Nesse contexto, a natureza está relacionada aos processos de saúde e doença e serve como fonte de medicamentos para tratamento de enfermidades. As plantas medicinais ocupam lugar de destaque no fornecimento de drogas e a medicina tradicional, praticada por diversas sociedades em todo o mundo, aparece como ferramenta crucial na busca por novas drogas de origem vegetal, à medida que fornece o conhecimento associado à experimentação popular, adquirido de geração em geração, para o uso de preparações vegetais no combate e profilaxia de doenças. Espécies do gênero Lychnophora (Asteraceae) são comumente utilizadas por populações nativas do cerrado brasileiro para tratar condições inflamatórias e algésicas. O estudo fitoquímico de L. passerina resultou no isolamento de duas misturas de triterpenos pentacíclicos a partir da fração acetato de etila, sendo eles lupeol, t r x sterol, pseudot r x sterol, α e β-amirinas. O extrato etanólico bruto da espécie L. passerina e suas frações metanólica e acetato de etila foram avaliados quanto a potencial atividade anti-inflamatória in vivo e in vitro. O extrato etanólico bruto de L. passerina e a fração acetato de etila exerceram uma potente atividade inibitória da produção de NO e TNF-α por m cróf gos J774.A1 estimulados por LPS/IFN-γ. Além disso, foram capazes de estimular drasticamente o aumento nos níveis de IL-10 no mesmo modelo celular de inflamação. Por outro lado, a fração metanólica inibiu fortemente a produção de TNF-α, m s foi in tiv n inibição da produção do NO e na indução da IL-10 por macrófagos estimulados por LPS/IFN-γ. O ensaio in vivo de avaliação do edema de pata induzido pela carragenina em camundongos revelou uma inibição da formação do edema para a pomada do extrato etanólico bruto de L. passerina (LPaE) a 10%, efeito este comparável à droga padrão, diclofenaco dietilamônio (11.6 mg/ml), não havendo diferença estatisticamente significativa entre as duas preparações. As pomadas contendo as frações metanólica (LPaM) e acetato de etila (LPaA) do extrato etanólico de L. passerina na concentração de 20% apresentaram atividade significativa. Os resultados in vivo confirmaram os potentes efeitos anti-inflamatórios encontrados in vitro para o extrato etanólico bruto de L. passerina, e uma atividade de menor intensidade para as frações metanólica e acetato de etila. O fracionamento cromatográfico do extrato etanólico bruto nas frações primárias metanólica e acetato de etila não aumentou as atividades observada in vivo e dessa maneira a atividade antiinflamatória de L. passerina pode estar relacionada a efeitos sinérgicos de diferentes substâncias presentes no extrato etanólico bruto. Na medicina tradicional brasileira, macerados alcoólicos das partes aéreas de L. passerina têm sido usados para tratar condições inflamatórias, por isso, o presente estudo pode sustentar o uso popular dessa planta.
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    Phthalocyanine photosensitizer in polyethylene glycol-block-poly(lactide-co-benzyl glycidyl ether) nanocarriers : probing the contribution of aromatic donor-acceptor interactions in polymeric nanospheres.
    (2019) Lana, Gwenaelle Elza Nathalie Pound; Garcia, Giani Martins; Trindade, Izabel Cristina; Oliveira, Patricia Capelari de; Pontífice, Thaís Godinho; Vilela, José Mário Carneiro; Andrade, Margareth Spangler; Nottelet, Benjamin; Postacchini, Bruna Bueno; Mosqueira, Vanessa Carla Furtado
    For best photosensitizer activity phthalocyanine dyes used in photodynamic therapy should be molecularly dispersed. Polyethylene glycol-block-polylactide derivatives presenting benzyl side-groups were synthesized to encapsulate a highly lipophilic phthalocyanine dye (AlClPc) and evaluate the effect of π-π interactions on the nanocarrier colloidal stability and dye dispersion. Copolymers with 0, 1, 2 and 6 mol% of benzyl glycidyl ether (BGE) were obtained via polyethylene glycol initiated ring-opening copolymerization of D,L-lactide with BGE. The block copolymers formed stable, monodisperse nanospheres with low in vitro cytotoxicity. AlClPc loading increased the nanosphere size and affected their colloidal stability. The photo-physical properties of the encapsulated dye, studied in batch and after separation by field flow fractionation, demonstrated the superiority of plain PEG-PLA over BGE-containing copolymers in maintaining the dye in its monomeric (non-aggregated) form in aqueous suspension. High dye encapsulation and sustained dye release suggest that these nanocarriers are good candidates for photodynamic therapy.
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    Release, transfer and partition of fluorescent dyes from polymeric nanocarriers to serum proteins monitored by asymmetric flow field-flow fractionation.
    (2021) Oliveira, Maria Alice de; Lana, Gwenaelle Elza Nathalie Pound; Oliveira, Patricia Capelari de; Pontífice, Thaís Godinho; Silva, Sabrina Emanuelle Dias; Machado, Marina Guimarães Carvalho; Postacchini, Bruna Bueno; Mosqueira, Vanessa Carla Furtado
    Fluorescent probes are used in drug nanocarrier pre-clinical studies or as active compounds in theranostics and photodynamic therapy. In the biological medium, nanoparticles interact with proteins, which can result in the off-target release of their cargo. The present study used asymmetric flow field-flow fractionation with online multi-angle laser light scattering and fluorescence detection (AF4-MALLS-FLD) to study the release, transfer, and partition of fluorescent dyes from polymeric nanoparticles (NP). NP formulations containing the dyes Rose Bengal, Rhodamine B, DiI, 3-(α-azidoacetyl)coumarin and its polymer conjugate, Nile Red, and IR780 and its polymer conjugate were prepared. NP suspensions were incubated in a medium with serum proteins and then analyzed by AF4. AF4 allowed efficient separation of proteins (< 10 nm) from fluorescently labeled NP (range of 54 – 180 nm in diameters). The AF4 analyses showed that some dyes, such as Rose Bengal, IR780, and Coumarin were transferred to a high extent (68-77%) from NP to proteins. By contrast, for DiI and dye-polymer conjugates, transfer occured to a lower extent. The studies of dye release kinetics showed that the transfer of IR780 from NP to proteins occurs at a high extent (~50%) and rate, while Nile Red was slowly released from the NP over time with reduced association with proteins (~20%). This experiment assesses the stability of fluorescence labeling of nanocarriers and probes the transfer of fluorescent dyes from NP to proteins, which is otherwise not accessible with commonly used techniques of separation, such as dialysis and ultrafiltration/centrifugation employed in drug encapsulation and release studies of nanocarriers. Determining the interaction and transfer of dyes to proteins is of utmost importance in the pre-clinical evaluation of drug nanocarriers for improved correlation between in vitro and in vivo studies.
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    Review on experimental treatment strategies against Trypanosoma cruzi.
    (2021) Mazzeti, Ana Lia; Oliveira, Patricia Capelari de; Bahia, Maria Terezinha; Mosqueira, Vanessa Carla Furtado
    Chagas disease is a neglected tropical disease caused by the protozoan Trypanosoma cruzi. Currently, only nitroheterocyclic nifurtimox (NFX) and benznidazole (BNZ) are available for the treatment of Chagas disease, with limitations such as variable efficacy, long treatment regimens and toxicity. Different strategies have been used to dis cover new active molecules for the treatment of Chagas disease. Target-based and phenotypic screening led to thousands of compounds with anti-T. cruzi activity, notably the nitroheter ocyclic compounds, fexinidazole and its metabolites. In addition, drug repurposing, drug combinations, re-dosing regimens and the development of new formulations have been evaluated. The CYP51 antifungal azoles, as posaconazole, ravuconazole and its prodrug fosravuconazole presented promising results in experimental Chagas disease. Drug combina tions of nitroheterocyclic and azoles were able to induce cure in murine infection. New treatment schemes using BNZ showed efficacy in the experimental chronic stage, including against dormant forms of T. cruzi. And finally, sesquiterpene lactone formulated in nanocar riers displayed outstanding efficacy against different strains of T. cruzi, susceptible or resistant to BNZ, the reference drug. These pre-clinical results are encouraging and provide interesting evidence to improve the treatment of patients with Chagas disease.