RESUMO
Brain inflammation is a key event triggering the pathological process associated with many neurodegenerative diseases. Current personalized medicine and translational research in neurodegenerative diseases focus on adipose-derived stem cells (ASCs), because they are patient-specific, thereby reducing the risk of immune rejection. ASCs have been shown to exert a therapeutic effect following transplantation in animal models of neuroinflammation. However, the mechanisms by which transplanted ASCs promote cell survival and/or functional recovery are not fully understood. We investigated the effects of ASCs in in vivo and in vitro lipopolysaccharide (LPS)-induced neuroinflammatory models. Brain damage was evaluated immunohistochemically using specific antibody markers of microglia, astroglia and oligodendrocytes. ASCs were used for intracerebral transplantation, as well as for non-contact co-culture with brain slices. In both in vivo and in vitro models, we found that LPS caused micro- and astroglial activation and oligodendrocyte degradation, whereas the presence of ASCs significantly reduced the damaging effects. It should be noted that the observed ASCs protection in a non-contact co-culture suggested that this effect was due to humoral factors via ASC-released biomodulatory molecules. However, further clinical studies are required to establish the therapeutic mechanisms of ASCs, and optimize their use as a part of a personalized medicine strategy.
RESUMO
We investigated the ultrastructural characteristics of mouse adipose-derived stem/stromal cells (ASCs) induced towards osteogenic lineage. ASCs were isolated from adipose tissue of FVB-Cg-Tg(GFPU)5Nagy/J mice and expanded in monolayer culture. Flow cytometry, histochemical staining, and electron microscopy techniques were used to characterize the ASCs with respect to their ability for osteogenic differentiation capacity. Immunophenotypically, ASCs were characterized by high expression of the CD44 and CD90 markers, while the relative content of cells expressing CD45, CD34 and CD117 markers was <2%. In assays of differentiation, the positive response to osteogenic differentiation factors was observed and characterized by deposition of calcium in the extracellular matrix and alkaline phosphatase production. Electron microscopy analysis revealed that undifferentiated ASCs had a rough endoplasmic reticulum with dilated cisterns and elongated mitochondria. At the end of the osteogenic differentiation, the ASCs transformed from their original fibroblast-like appearance to having a polygonal osteoblast-like morphology. Ultrastructurally, these cells were characterized by large euchromatic nucleus and numerous cytoplasm containing elongated mitochondria, a very prominent rough endoplasmic reticulum, Golgi apparatus and intermediate filament bundles. Extracellular matrix vesicles of variable size similar to the calcification nodules were observed among collagen fibrils. Our data provide the ultrastructural basis for further studies on the cellular mechanisms involved in osteogenic differentiation of mouse adipose-derived stem/stromal cells. Microsc. Res. Tech. 79:557-564, 2016. © 2016 Wiley Periodicals, Inc.