Biodegradable, spun nanocomposite polymeric fibrous dressings loaded with bioactive biomolecules for an effective wound healing: a review

In recent years, spinning techniques have been highlighted for their capability of producing complex, fibrous and reticulated constructs with great potential for biomedicine. Indeed, biodegradable constructs based on polymeric fibers are desirable in wound healing due to their large surface area, interconnectivity, open pore structure, and controlled mechanical strength. Modern dressings made of spun biopolymers can incorporate active compounds within their matrix, which can be delivered topically, very beneficial to the healing process. In the present work, we explore the spinning techniques used to process polymers in the form of fibers, assess the properties of some of the most common biodegradable polymers used in wound dressing production, and highlight the potentialities of important biomolecules used in the production of new generation of bioactive wound dressings.Authors acknowledge the Portuguese Foundation for Science and Technology (FCT), FEDER funds by means of Portugal 2020 Competitive Factors Operational Program (POCI) and the Portuguese Government (OE) for funding the project PEPTEX with reference POCI-01-0145-FEDER-028074. Authors also acknowledge project UID/CTM/00264/2019 of 2C2T funded by FCT/MCTES

Interleukin-1β induces human cementoblasts to support osteoclastogenesis

Injury of the periodontium followed by inflammatory response often leads to root resorption. Resorption is accomplished by osteoclasts and their generation may depend on an interaction with the cells in direct contact with the root, the cementoblasts. Our study aimed to investigate the role of human cementoblasts in the formation of osteoclasts and the effect of interleukin (IL)-1β hereupon. Extracted teeth from healthy volunteers were subjected to sequential digestion by type I collagenase and trypsin. The effect of enzymatic digestion on the presence of cells on the root surface was analyzed by histology. Gene expression of primary human cementoblasts (pHCB) was compared with a human cementoblast cell line (HCEM). The pHCBs were analyzed for their expression of IL-1 receptors as well as of receptor activator of nuclear factor kappa-B ligand (RANKL) and osteoprotegerin (OPG). In a co-culture system consisting of osteoclast precursors (blood monocytes) and pHCBs, the formation of osteoclasts and their resorptive activity was assessed by osteo-assay and ivory slices. The cells obtained after a 120 min enzyme digestion expressed the highest level of bone sialoprotein, similar to that of HCEM. This fraction of isolated cells also shared a similar expression pattern of IL-1 receptors (IL1-R1 and IL1-R2). Treatment with IL-1β potently upregulated RANKL expression but not of OPG. pHCBs were shown to induce the formation of functional osteoclasts. This capacity was significantly stimulated by pretreating the pHCBs with IL-1β prior to their co-culture with human blood monocytes. Our study demonstrated that cementoblasts have the capacity to induce osteoclastogenesis, a capacity strongly promoted by IL-1β. These results may explain why osteoclasts can be formed next to the root of teeth