Schwann-cell cylinders grown inside hyaluronic-acid tubular scaffolds with gradient porosity

[EN] Cell transplantation therapies in the nervous system are frequently hampered by glial scarring and cell drain from the damaged site, among others. To improve this situation, new biomaterials may be of help. Here, novel single-channel tubular conduits based on hyaluronic acid (HA) with and without poly-l-lactide acid fibers in their lumen were fabricated. Rat Schwann cells were seeded within the conduits and cultured for 10days. The conduits possessed a three-layered porous structure that impeded the leakage of the cells seeded in their interior and made them impervious to cell invasion from the exterior, while allowing free transport of nutrients and other molecules needed for cell survival. The channel's surface acted as a template for the formation of a cylindrical sheath-like tapestry of Schwann cells continuously spanning the whole length of the lumen. Schwann-cell tubes having a diameter of around 0.5mm and variable lengths can thus be generated. This structure is not found in nature and represents a truly engineered tissue, the outcome of the specific cell-material interactions. The conduits might be useful to sustain and protect cells for transplantation, and the biohybrids here described, together with neuronal precursors, might be of help in building bridges across significant distances in the central and peripheral nervous system.The authors acknowledge financing through projects MAT2011-28791-C03-02 and 03, and ERA-NET NEURON project PRI-PIMNEU-2011-1372. We thank the Cytomics Core Facility at Principe Felipe Research Center (CIPF, Valencia, Spain) for their support and advice in flow cytometry experiments, and the Electron Microscopy Service at the UPV, where the SEM images were obtained. The authors thankfully acknowledge the reviewers' comments, which have helped to improve the clarity of the paper's presentation.Vilariño Feltrer, G.; Martínez Ramos, C.; Monleon De La Fuente, A.; Vallés Lluch, A.; Moratal Pérez, D.; Barcia Albacar, JA.; Monleón Pradas, M. (2016). Schwann-cell cylinders grown inside hyaluronic-acid tubular scaffolds with gradient porosity. Acta Biomaterialia. 30:199-211. https://doi.org/10.1016/j.actbio.2015.10.040S1992113

8 prenylnaringenin novel phytoestrogen, inhibits angiogenesis in vitro and vivo.

8-Prenylnaringenin is a recently discovered phytoestrogen. Using an in vitro model of angiogenesis in which endothelial cells can be induced to invade a three-dimensional collagen gel within which they form capillary-like tubes, we demonstrate that 8-prenylnaringenin inhibits angiogenesis induced by basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), or the synergistic effect of the two cytokines in combination, with an IC(50) of between 3 and 10 microM. This effect was seen with bovine microvascular endothelial cells derived from the adrenal cortex (BME cells) and with endothelial cells from the bovine thoracic aorta (BAE cells). The inhibitory effects of 8-prenylnaringenin were found to be roughly equipotent to those of genistein that has previously been shown to inhibit angiogenesis in vitro. Early chorioallantoic membrane (CAM) assay results showed reductions in both vessel lengths and vein diameters, with similar potency in the 8-prenylnaringenin and genistein groups. Similar effects on the CAM vessels were seen when the two substances were co-added. These findings suggest that 8-prenylnaringenin has potential therapeutic applications for diseases in which angiogenesis is an important component.Michael S. Pepper, Susan J. Hazel, Michael Hümpel, Wolf-Dieter Schleunin