Dados do Trabalho

Título/Title/Titulo

BPA and TCDD Action on Rat Adipose-derived Stem Cells (rASCs) Differentiation Potential.

Introdução/Introduction/Introdución

Mesenchymal stem cells (MSCs) are a heterogeneous population that proliferates in vitro as plastic-adherent cells and have fibroblast-like morphology. They can form colonies in vitro and can differentiate into bone, cartilage, fat cells, and others. Adipose-derived stem cells (ASCs) originate in the adipose tissue and due to their easy processing and isolation techniques, they are used for regenerative medicine purposes to prevent and treat diseases occurring in a variety of tissues and organs. Considering practical issues, the use of experimental tissue-engineered constructs demands urgency for approval and implantation, and also an increase in clinical trials activity has been noticed in the last decades.
Therefore, an important issue to be considered when working with cell therapy is the possibility for chemical contamination. Endocrine disrupting chemicals (EDCs) are lipophilic compounds closely related to adipose tissue. BPA and TCDD are the best known and relevant EDCs that have been recently studied. They are also called obesogens due to their inductive adipogenic differentiation.

Objetivos - Metodologia - Resultados - Discussão dos Resultados/Objectives - Methodology - Results - Discussion of Results/Objetivos - Metodología - Resultados - Discusión de los resultados

Accordingly, this study aimed to access and quantify the differentiation potential of rat adipose-derived stem cells (rASCs) exposed to 1uM, 10uM of BPA and 10nM of TCDD. These concentrations were previously defined based on the literature by half maximal inhibitory concentration (IC50) and lethal dose (LD) tests. Other cell processes were further investigated.

Primary culture of rASCs was harvested and isolated by Wistar Rats. In the fourth passage, cells were characterized for the ASC population by flow Cytometric and tri-lineage differentiation kit analyses.

A cytotoxicity assay by MTT was performed to confirm possible deleterious activity of these compounds. Apoptosis/necrosis by Flow Cytometry and the differentiation potential was also performed. Comet assay was accessed to verify DNA damage.

Statistical analysis was based on mean S.E.M. or S.D. The statistical differences among two or more groups were determined by ANOVA, followed by the post-hoc Tukey´s multiple comparison tests vs the respective control group. The statistical differences between two groups were analyzed using student's t-test. Statistical significance was set at P<0.05. The analysis was performed using Prism software. Data represent mean ± SE from three independent experiments in duplicate or triplicate repetitions.
Results demonstrated that 10uM of BPA and 10nM of TCDD were able to induce proliferation according to MTT analysis. Apoptosis/necrosis assay showed that BPA and TCDD were able to induce cell death. Comet assay analysis presented DNA damage in rASCs from all experimental groups. When cells were quantified in terms of adipogenic differentiation,1uM of BPA caused significant oil droplets formation, while 10uM of BPA and 10nM of TCDD showed a decrease on adipocyte differentiation. Osteogenic differentiation did not show significant results among groups.

Considerações Finais/Final considerations/Consideraciones finales

The present results evidenced that 1uM BPA concentration had the most expressive outcomes in terms of adipocyte differentiation. Thus, it is reasonable to infer that low doses (1uM) were able to induce this process. Our results showed that rASCs exposed to BPA and TCDD demonstrated alterations on important cellular processes, such as cell proliferation, apoptosis rate, adipogenic differentiation, and DNA damage.

Palavras-chave/Key words/Palabras clave

Mesenchymal stem cells, Adipose-derived stem cells, endocrine disruptors, Bisphenol A, TCDD, Cell therapy.