Ação da azitromicina em vilos placentários humanos infectados por Toxoplasma gondii: um modelo experimental de tratamento da toxoplasmose congênita

Toxoplasmosis is a worldwide zoonosis, caused by the protozoan Toxoplasma gondii. Although it is an usuall asymptomatic infection, the toxoplasmosis can manifest as a potentially serious disease in immunocompromised individuals and when acquired during pregnancy. The treatment of toxoplasmosis during pregnancy when the fetal infection is confirmed is based in the association of pyrimethamine, sulfadiazine and folinic acid (PSA). Pyrimethamine is potentially toxic and should not be used in the first trimester of pregnancy. The azalide antibiotic azithromycin presents efficacy in a wide range of bacterial infections and antimalarial activity, and it is considered safe for use during pregnancy. The objective of the present study was to evaluate the efficacy of azithromycin in controlling T. gondii infection in human placentas from third trimester. The placental villi were infected or not with tachyzoites of T. gondii and treated with various concentrations of azithromycin or PSA. The villous placenta were processed for morphological analysis, T. gondii intracellular proliferation and immunohistochemistry; and supernatants were evaluated for measuring the activity of LDH, cytokine, hormone production and nitrite. In non-cytotoxic doses (200 and 1000 ug/ml), treatment with azithromycin or PSA did not alter the morphology of the placental villi. Both antibiotics were able to reduce significantly the T. gondii intracellular proliferation, and the treatment with PSA promoted increase of IL-12 and IL-10 reduce, whereas azithromycin induced an increase in IL-2 and IL-6 in the groups infected with T. gondii, and reduced production of estradiol, progesterone and hCG. Moreover, the previous treatment of T. gondii with antibiotics was able to control the replication of the parasite, showing direct action of drugs on T. gondii. Thus, our data suggest that azithromycin, as PSA, was able to control the infection with T. gondii in an experimental model of human placental explants of third trimester. Additionally our data suggest that azithromycin may be an alternative selection for treatment of congenital toxoplasmosis, expanding the therapeutic strategies to control the parasite in maternal fetal interface.Doutor em Imunologia e Parasitologia AplicadasA toxoplasmose é uma zoonose de distribuição mundial, causada pelo protozoário Toxoplasma gondii. Apesar de geralmente apresentar-se como uma infecção assintomática, a toxoplasmose pode manifestar-se como uma doença potencialmente grave em indivíduos imunocomprometidos e quando adquirida durante a gestação, pode associar-se a complicações fetais e abortos. O tratamento da toxoplasmose durante a gestação, caso haja confirmação da infeccão fetal, baseia-se na combinação das drogas: pirimetamina, sulfadiazina e ácido folínico (PSA). No entanto, estes fármacos apresentam inúmeros efeitos adversos, não devendo ser indicado no primeiro trimestre gestacional. A azitromicina é um antibiótico azalídeo com ação em uma ampla gama de infecções bacterianas, bem como atividade antimalárica, sendo considerado seguro para utilização durante a gestação. Assim, o objetivo do presente estudo foi avaliar a eficácia da azitromicina no controle de T. gondii usando o modelo experimental de explantes placentários de terceiro trimestre. Os vilos placentários foram infectados ou não com taquizoítas de T. gondii e tratados com diferentes concentrações de azitromicina ou PSA. Esses vilos placentários foram processados para análise morfológica, ensaio de proliferação de T. gondii e imuno-histoquímica e, os sobrenadantes, avaliados para mensuração da atividade de LDH, dosagem de citocinas, produção hormonal e de nitrito. Em doses não citotóxicas (200 e 1000 μg/ml), os tratamentos com azitromicina ou PSA não alteraram a morfologia dos vilos placentários. Ambos tratamentos foram capazes de reduzir significativamente a proliferação intracelular T. gondii, sendo que o tratamento com PSA promoveu aumento de IL-12 e redução de IL-10, enquanto a azitromicina induziu aumento na produção de IL-2 e IL-6 nos grupos infectados com T. gondii, além de redução na produção dos hormônios estradiol, progesterona e hCG. Além disso, o tratamento prévio dos parasitos com antibióticos foi capaz de controlar a replicação dos mesmos, demonstrando ação direta das drogas sobre T. gondii. Assim, nossos dados indicam que a azitromicina, assim como PSA, são capazes de controlar a infecção por T. gondii nos vilos placentários humanos de terceiro trimestre gestacional. Além disso, nossos dados sugerem a azitromicina como uma alternativa no tratamento da toxoplasmose congênita, ampliando as estratégias terapêuticas utilizadas no controle do parasito na interface materno fetal

Biomaterials and Adipose-Derived Mesenchymal Stem Cells for Regenerative Medicine: A Systematic Review

The use of biological templates for the suitable growth of adipose-derived mesenchymal stem cells (AD-MSC) and “neo-tissue” construction has exponentially increased over the last years. The bioengineered scaffolds still have a prominent and biocompatible framework playing a role in tissue regeneration. In order to supply AD-MSCs, biomaterials, as the stem cell niche, are more often supplemented by or stimulate molecular signals that allow differentiation events into several strains, besides their secretion of cytokines and effects of immunomodulation. This systematic review aims to highlight the details of the integration of several types of biomaterials used in association with AD-MSCs, collecting notorious and basic data of in vitro and in vivo assays, taking into account the relevance of the interference of the cell lineage origin and handling cell line protocols for both the replacement and repairing of damaged tissues or organs in clinical application. Our group analyzed the quality and results of the 98 articles selected from PubMed, Scopus and Web of Science. A total of 97% of the articles retrieved demonstrated the potential in clinical applications. The synthetic polymers were the most used biomaterials associated with AD-MSCs and almost half of the selected articles were applied on bone regeneration

Azithromycin is able to control Toxoplasma gondii infection in human villous explants

Submitted by Nuzia Santos ([email protected]) on 2015-02-19T14:46:19Z No. of bitstreams: 1 2014_084.pdf: 1442525 bytes, checksum: 0ea3f08436712815ef93363ee3beae9e (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2015-02-19T14:49:27Z (GMT) No. of bitstreams: 1 2014_084.pdf: 1442525 bytes, checksum: 0ea3f08436712815ef93363ee3beae9e (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2015-02-19T14:55:14Z (GMT) No. of bitstreams: 1 2014_084.pdf: 1442525 bytes, checksum: 0ea3f08436712815ef93363ee3beae9e (MD5)Made available in DSpace on 2015-02-19T14:55:14Z (GMT). No. of bitstreams: 1 2014_084.pdf: 1442525 bytes, checksum: 0ea3f08436712815ef93363ee3beae9e (MD5) Previous issue date: 2014Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Laboratório de Imunofisiologia da Reprodução. Uberlândia, MG, Brasil.Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Laboratório de Imunofisiologia da Reprodução. Uberlândia, MG, Brasil.Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Laboratório de Imunofisiologia da Reprodução. Uberlândia, MG, Brasil.Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Laboratório de Imunopatologia. Uberlândia, MG, Brasil.Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Laboratório de Imunofisiologia da Reprodução. Uberlândia, MG, Brasil.Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Laboratório de Imunofisiologia da Reprodução. Uberlândia, MG, Brasil.Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Laboratório de Imunopatologia. Uberlândia, MG, Brasil.Fundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratório de Doença de Chagas. Belo Horizonte, MG, Brasil.Universidade Federal de Uberlândia. Faculdade de Medicina. Departamento de Ginecologia e Obstetricia. Uberlândia, MG, Brasil.Universidade Federal de Uberlândia. Instituto de Ciencias Biomédicas. Laboratório de Imunopatologia. Uberlândia, MG, Brasil.Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Laboratório de Imunofisiologia da Reprodução. Uberlândia, MG, Brasil.BACKGROUND: Although Toxoplasma gondii infection is normally asymptomatic, severe cases of toxoplasmosis may occur in immunosuppressed patients or congenitally infected newborns. When a fetal infection is established, the recommended treatment is a combination of pyrimethamine, sulfadiazine and folinic acid (PSA). The aim of the present study was to evaluate the efficacy of azithromycin to control T. gondii infection in human villous explants. METHODS: Cultures of third trimester human villous explants were infected with T. gondii and simultaneously treated with either PSA or azithromycin. Proliferation of T. gondii, as well as production of cytokines and hormones by chorionic villous explants, was analyzed. RESULTS: Treatment with either azithromycin or PSA was able to control T. gondii infection in villous explants. After azithromycin or PSA treatment, TNF-α, IL-17A or TGF-β1 levels secreted by infected villous explants did not present significant differences. However, PSA-treated villous explants had decreased levels of IL-10 and increased IL-12 levels, while treatment with azithromycin increased production of IL-6. Additionally, T. gondii-infected villous explants increased secretion of estradiol, progesterone and HCG+β, while treatments with azithromycin or PSA reduced secretion of these hormones concurrently with decrease of parasite load. CONCLUSIONS: In conclusion, these results suggest that azithromycin may be defined as an effective alternative drug to control T. gondii infection at the fetal-maternal interfac

Characterization of Crystalline Phase of TiO2 Nanocrystals, Cytotoxicity and Cell Internalization Analysis on Human Adipose Tissue-Derived Mesenchymal Stem Cells

Titanium dioxide (TiO2) is manufactured worldwide as crystalline and amorphous forms for multiple applications, including tissue engineering, but our study proposes analyzing the impact of crystalline phases of TiO2 on Mesenchymal Stem Cells (MSCs). Several studies have already described the regenerative potential of MSCs and TiO2 has been used for bone regeneration. In this study, polydispersity index and sizes of TiO2 nanocrystals (NCs) were determined. Adipose tissue-derived Mesenchymal Stem Cells (AT-MSCs) were isolated and characterized in order to evaluate cellular viability and the internalization of nanocrystals (NCs). All of the assays were performed using the TiO2 NCs with 100% anatase (A), 91.6% anatase/9.4% rutile (AR), 64.6% rutile/35.4% anatase (RA), and 84.0% rutile/16% brookite (RB), submitted to several concentrations in 24-h treatments. Cellular localization of TiO2 NCs in the AT-MSCs was resolved by europium-doped NCs. Viability was significantly improved under the predominance of the rutile phase in NCs with localization restricted at the cytoplasm, suggesting that AR and RA NCs are not genotoxic and can be associated with most cellular activities and metabolic pathways, including glycolysis and cell division