Aim: The proposal of this study was to evaluate, in vitro, the potential paracrine effect of human adipose-derived stem cells (hASCs) to promote lymphangiogenesis in lymphatic endothelial cells isolated from rat diaphragmatic lymphatic vessels. Materials & methods: ELISA on VEGFA, VEGFC and IL6 in hASC-conditioned medium; LYVE1 immunostaining; and gene expression of PROX1, VEGFR3, VEGFC, VEGFA and IL6 were the methods used. Results: In 2D culture, hASC-conditioned medium was able to promote lymphatic endothelial cell survival, maintenance of endothelial cobblestone morphology and induction to form a vessel-like structure. Conclusion: The authors' results represent in vitro evidence of the paracrine effect of hASCs on lymphatic endothelial cells, suggesting the possible role of hASC-conditioned medium in developing new therapeutic approaches for lymphatic system-related dysfunction such as secondary lymphedema.

This work is addressed to provide, by in vitro experiments, results on the repercussion that a nanostructured scaffold could have on viability, differentiation and secretion of bioactive factors of human adipose-derived stem cells (hASCs) when used in association to promote angiogenesis, a crucial condition to favour tissue regeneration. To achieve this aim, we evaluated cell viability and morphology by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay and microscopy analysis, respectively. We also investigated the expression of some of those genes involved in angiogenesis and differentiation processes utilizing quantitative polymerase chain reaction (qPCR), whereas the amounts of Vascular Endothelial Growth Factor A, Interleukin 6 and Fatty Acid-Binding Protein 4 secreted in the culture medium, were quantified by enzyme-linked immunosorbent assay (ELISA). Results suggested that, in the presence of the scaffold, cell proliferation and the exocytosis of factors involved in the angiogenesis process are reduced; by contrast, the expression of those genes involved in hASC differentiation appeared enhanced. To guarantee cell survival, the construct dimensions are, generally, smaller than clinically required. Furthermore, being the paracrine event the primary mechanism exerting the beneficial effects on injured tissues, the use of conditioned culture medium instead of cells may be convenient.

Aim:To demonstrate that cobalt nanoparticles doses are safe for use in humans and to understand the consequences of the particulate effects, which may persist inside the cells. Materials & methods: Human adipose stem cells were used. We evaluated cell recovery by viability test, morphology and ultrastructure using electronic and optical microscopy, while gene expression was assessed utilizing real-time PCR. Results: After exposure, most stem cells recovered their normal function. Co 3 O 4 -nanoparticles remained inside the cell for the entirety of the considered time. A slight modification of gene expression was observed in the exposed cells. Conclusion: After exposure to 100 M cobalt nanoparticles, most cells returned to normal function. Nanoparticle toxicity was due to ions released by dissolution as well as from the nanoparticles themselves.Cobalt (Co), along with iron (Fe) and nickel (Ni), is a transition metal belonging to group VIIIb of the periodic table. It is an essential element for cell physiology and animal health; in fact, Co is an important constituent of vitamin B12 and is involved in several cell pathways, such as the metabolism of fats and carbohydrates, the conversion of folate into their active form, protein synthesis and the prevention of demyelination [1]. Co deficiency is quite unusual and potentially lethal; conversely, Co intoxication, caused by excessive levels in the body, occurs more frequently and is dangerous as well [2].Along with Fe and Ni, Co is one of the three naturally occurring magnetic metals; it is able to retain its magnetic properties at high temperatures. Therefore, Co has many applications, such as for energy storage systems and catalytic processes [3]. In particular, Co, in its bulk form, is used for green technologies and is also an integral component in powering electric vehicles, wind and wave generators, solar energy technologies sensors, electrochemistry and magnetic fluids [4,5]. However, at the nanoscale dimension, too, Co is promising for several nanotechnological applications ranging from chemistry to nanomedicine, where it is used as a highly sensitive MRI contrast agent [6]. In this scenario, an issue that should be considered is the exponential growth of production, use and discharge of Co nanoparticles (Co-NPs). Consequently, the human body is very likely to come into contact, intentionally or not, with Co-NPs that may easily enter the body in different ways [7][8][9], encounter cells of different tissues and then act on them by perturbing their physiology [10]. In this perspective, special attention should be paid to the presence of multipotent stem cells, a population residing in almost all human tissues that fulfills important functions, including renewal, repair and remodeling [11]. Among the different stem cell populations, mesenchymal stem cells (MSCs) are very interesting due to their great potential in many medical applications, such as regenerative medicine, bone marrow transplantation and orthopedic injuries. Unfortunately, MSCs are more sensitive ...

Nanoparticles (NPs) have become a very exciting research avenue, with multitudinous applications in various fields, including the biomedical one, whereby they have been gaining considerable interest as drug carriers able...

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