Interferência das diferentes fases dos nanocristais de Dióxido de Titânio na migração de células-tronco mesenquimais de tecido adiposo humano.

Trabalho de Conclusão de Curso (Graduação)Células-tronco mesenquimais (CTMs) são definidas como células adultas indiferenciadas que possuem a característica de autorrenovação, podendo ser isoladas de vários tecidos humanos. A nanobiotecnologia pode auxiliar na eficácia da regeneração tecidual, por isso a associação de CTM com nanocristais está sendo proposto neste trabalho com o uso do dióxido de titânio (TiO2), que possui três estruturas cristalinas: anatase, rutilo e broquita. O objetivo desse trabalho foi analisar in vitro a capacidade de migração das células tronco mesenquimais de tecido adiposo (CTM-TA) associadas a NCs de TiO2 em diferentes fases nas concentrações de 50 µg/mL, 100 µg/mL, 150 µg/mL e 200 µg/mL após sua preparação com agente estabilizador. Realizou-se primeiramente o isolamento e a caracterização das CTMs, em seguida foi sintetizado os NCs de TiO2 e realizado o teste de dispersão e por fim foi realizado o ensaio de migração celular. A migração aumentou na concentração de 50 µg/mL na fase rutilo/broquita fechando a ferida (in vitro) em 80%, enquanto na fase anatase não houve alteração na migração celular. Portanto, a migração de CTM-TA in vitro aumenta quando tratada com NCs de TiO2 na fase rutilo/broquita, dispersos com agente estabilizador na concentração de 50µg/mL

Biocompatibility of Doped Semiconductors Nanocrystals and Nanocomposites

Exposure of humans and environment to nanocrystals are inevitable, and nanotoxicological analyses are a requirement. The wide variety of nanocrystals with different applications is increasing, and characterization of their effects after exposure includes their potential toxicity and uses. This review summarizes the characterization of doped nanocrystals and nanocomposites, Ca-doped ZnO, Ag- and Eu-doped ZnO and Ni-doped ZnO NCs, their biocompatibility and applications. This review uncovers how these nanocrystals present desirable biocompatible properties, which can be useful as antitumoral and antimicrobial inducing agents, which differ markedly from toxic properties observed in other general nanocrystals

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

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