Otoliths-composed gelatin/sodium alginate scaffolds for bone regeneration

Evidence that otoliths, mineral-rich limestone concrescences present in the inner ear of bone fishes, can accelerate bone formation in vivo has been previously reported. The goal of this work was the development, characterization, and evaluation of the cytocompatibility of otoliths-incorporated sodium alginate and gelatin scaffolds. Cynoscion acoupaderived otoliths were characterized by X-ray fluorescence spectrometry (FRX), particle size, free lime, and weight loss by calcination. Furthermore, otoliths were incorporated into sodium alginate (ALG/OTL-s) or gelatin (GEL/OTL-s) scaffolds, previously developed by freeze-drying. Then, the scaffolds were characterized by thermogravimetric analysis (TGA/DTG), differential scanning calorimetry (DSC), infrared spectroscopy with Fourier transform (FTIR), swelling tests, and scanning electron microscopy (SEM). Cytotoxicity assays were run against J774.G8 macrophages and MC3T3-E1 osteoblasts. Data obtained from TGA/DTG, DSC, and FTIR analyses confirmed the interaction between otoliths and the polymeric scaffolds. SEM showed the homogeneous porous 3D structure rich in otolith micro-fragments in both scaffolds. Swelling of the GEL/OTL-s (63.54±3.0%) was greater than of ALG/OTL-s (13.36±9.9%) (p0.05) and significantly higher than that treated with Triton-X (p0.05). However, by 48 h, only ALG/OTL-s showed growth similar to control (p>0.05), whereas GEL/OTL showed a significantly lower growth index (p<0.05). In conclusion, the physicochemical profiles suggest proper interaction between the otoliths and the two developed polymeric 3D scaffolds. Moreover, both materials showed cytocompatibility with J774.G8 macrophages but the growth of MC3T3-E1 osteoblasts was higher when exposed to ALG/OTL-s. These data suggest that sodium alginate/otoliths scaffolds are potential biomaterials to be used in bone regeneration applications.We would like to thank the National Council for Scientific and Technological Development (CNPq) and the Foundation for Research and Technological Innovation Support of the State of Sergipe for the financial support in this study. EMBS acknowledges the sponsorship of the projects M-ERA-NET-0004/2015-PAIRED and UIDB/04469/2020 (strategic fund), received support from the Portuguese Science and Technology Foundation, Ministry of Science and Education (FCT/MEC) through national funds, and was co-financed by FEDER, under the Partnership Agreement PT2020.info:eu-repo/semantics/publishedVersio

Estudo da atividade moluscicida das plantas oriundas da Restinga de Jurubatiba

O estudo das plantas medicinais tem-se tornado uma importante fonte de pesquisa e interesse científico devido ao seu valor em nível de estrutura química e propriedades farmacológicas. A esquistossomose é um problema de saúde pública que atinge milhares de pessoas que vivem em áreas endêmicas. Por seu aspecto socioeconômico, devido à falta de saneamento básico eficiente em muitas áreas, está incluída entre as doenças negligenciadas. Seu tratamento é considerado eficaz, porém existe a necessidade de medidas profiláticas que reduzam o número de pessoas infectadas atendidas pelas redes de saúde coletiva. Dentre essas medidas, existe o combate ao hospedeiro intermediário do agente etiológico da doença, o caramujo de água doce do gênero Biomphalaria. Este molusco é crucial para a transmissão da doença, e seu controle iria interromper o ciclo da esquistossomose. O método de controle atualmente utilizado para este fim possui grande impacto ambiental, não sendo, portanto, uma alternativa viável. Nesse contexto, as plantas da Restinga de Jurubatiba possuem diversas atividades terapêuticas conhecidas popularmente ou cientificamente estudas. O uso de seus extratos pode ser uma importante estratégia para o controle do molusco e a consequente redução do número de pessoas que contraem a esquistossomose. O objetivo desse trabalho, portanto, é avaliar a atividade moluscicida dos extratos das plantas Eugenia sulcata, Manilkara subsericea, Neomitranthes obscura e Myrciaria floribunda, suas frações e substâncias isoladas, sobre a espécie Biomphalaria glabrata. Foi realizado o ensaio de atividade moluscicida para avaliar a letalidade dos extratos de plantas sobre a espécie Biomphalaria glabrata, em tempos de até 96 horas. E, para avaliar a toxidade dos extratos em células de linhagem, foram realizados ensaios de liberação da enzima lactato desidrogenase e redução da resazurina. Os resultados mostraram maior atividade moluscicida nas frações em hexano e diclorometano de Myrciaria floribunda, com valores de DL50 de 3,3 e 6,2 ppm respectivamente e, em menor escala, nos extratos brutos do caule de Neomitranthes obscura e Manilkara subsericea, e na fração acetato de etila desta última, da qual foram isoladas três substâncias: miricetina, quercetina e ácido ursólico, apresentando atividade moluscicida em menores concentrações, com valores de DL50 de 0,04 ppm, 0,08 ppm e 1,57 ppm respectivamente. Tais resultados não demonstraram toxidade em células de mamíferos. Este trabalho aponta para um foco de estudo para uma alternativa profilática para o controle do hospedeiro intermediário da esquistossomose mansônica.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThe study of the medicinal plants has become a major source of research and scientific interest because of their value at the level of chemical structure and pharmacological properties. Schistosomiasis is a public health problem that affects thousands of people living in endemic areas. By their socioeconomic aspect, due to the lack of effective sanitation in many areas, it is included among the neglected diseases. The treatment is considered effective, but there is the need for effective preventive measures to reduce the numbers of infected people served by the public health networks. Among these measures, there is the fight against intermediate hosts of the disease, the freshwater snail Biomphalaria. This mollusk is crucial to the development of the disease and its control would stop the schistosomiasis cycle. The control method currently used for this purpose has a large environmental impact, and therefore not a viable alternative. In this context, plants from Jurubatiba sandbank have several therapeutic activities known popularly or scientifically studied. The use of its extracts may be an important strategy for the mollusk control and the consequent reduction in the number of people contracting schistosomiasis. The aim of this study, therefore, is to evaluate the molluscicidal activity of the extracts from plants Eugenia sulcata, Manilkara subsericea, Neomitranthes obscura and Myrciaria floribunda, its fractions and isolated compounds on the specie Biomphalaria glabrata. It carried out the molluscicidal activity assay to assess the lethality of plant extracts on Biomphalaria glabrata species at times up to 96 hours. In order to evaluate the toxicity of extracts of cell line were performed assays lactate dehydrogenase release and reduction of resazurin. The results showed higher molluscicidal activity in the fractions in hexane and dichloromethane of Myrciaria floribunda, with LD50 values of 3.3 and 6.2 ppm, respectively, and to a lesser extent, in stem crude extracts of Neomitranthes obscure and Manilkara subsericea, and the ethyl acetate fraction of the latter, from which three substances were isolated: myricetin, quercetin and ursolic acid, with molluscicidal activity at lower concentrations, with LD50 values of 0.04 ppm, 0.08 ppm and 1.57 ppm respectively. There is no toxicity in mammalian cells. This work points to a focus of study for a prophylactic alternative to control the intermediate host of schistosomiasis

Effect of Dioscorea villosa extract and the phytoestrogen diosgenin on ovariectomized mice with zymosan-induced arthritis

Abstract Humans are exposed to natural compounds such as phytoestrogens primarily through diet and supplements. These compounds promote health by alleviating the symptoms and illnesses associated with menopause and arthritis. Diosgenin (DSG) occurs naturally in plants such as Dioscorea villosa (DV) and binds to estrogen receptors, so it may have similar effects to this hormone, including against arthritis. Thus, we investigated the effect of chronic treatment with dry extract of DV and its phytoestrogen DSG on ovariectomized mice with arthritis. We found that dry extract of Dioscorea villosa (DV) contains the phytoestrogen diosgenin (DSG) in its composition. Furthermore, arthritic mice treated with DV and DSG showed reduced neutrophil accumulation in the articular cartilage. Also, the dry extract of DV administered orally (v.o) did not alter the leukocyte count in the joints or promote changes in the reproductive tract. However, DSG altered these parameters, with possible beneficial effects by reducing symptoms related to reproductive aging. Thus, oral treatment with dry extract of DV and subcutaneous (s.c) treatment with DSG showed promise by acting against inflammation caused by arthritis and reducing symptoms in the reproductive tract due to menopause