ABSTRACT
Spontaneously formed hydrogels are attracting increasing interest as injectable or wound dressing materials because they do not require additional reactions or toxic crosslinking reagents. Highly valuable properties such as low viscosity before external application, adequate filmogenic capacity, rapid gelation and tissue adhesion are required in order to use them for those therapeutic applications. In addition, biocompatibility and biodegradability are also mandatory. Accordingly, biopolymers, such as hyaluronic acid (HA) and chitosan (CHI), that have shown great potential for wound healing applications are excellent candidates due to their unique physiochemical and biological properties, such as moisturizing and antimicrobial ability, respectively. In this study, both biopolymers were modified by covalent anchoring of catechol groups, and the obtained hydrogels were characterized by studying, in particular, their tissue adhesiveness and film forming capacity for potential skin wound healing applications. Tissue adhesiveness was related to o-quinone formation over time and monitored by visible spectroscopy. Consequently, an opposite effect was observed for both polysaccharides. As gelation advances for HA-CA, it becomes more adhesive, while competitive reactions of quinone in CHI-CA slow down tissue adhesiveness and induce a detriment of the filmogenic properties.
ABSTRACT
The use of nanotechnology has revolutionized many biotechnological sectors, from bioengineering to medicine, passing through food and cosmetic fields. However, their clinic and industrial application has been into the spotlight due to their safety risk and related side effects. As a result, Green Nanoscience/Nanotechnology emerged as a strategy to prevent any associated nanotoxicity, via implementation of sustainable processes across the whole lifecycle of nanoformulation. Notwithstanding its success across inorganic nanoparticles, the green concept for organic nanoparticle elaboration is still at its infancy. This, coupled with the organic nanoparticles being the most commonly used in biomedicine, highlights the need to implement specific green principles for their elaboration. In this review, we will discuss the possible green routes for the proper design of organic nanoparticles under the umbrella of Green Nanoscience: from the extraction of nanomaterials and active compounds to their final nanoformulation.
Subject(s)
Nanoparticles , Nanostructures , NanotechnologyABSTRACT
Inflammation and oxidative stress pathways have emerged as novel targets in the management of inflammatory bowel diseases (IBD). Targeting the drug to the inflamed colon remains a challenge. Nanostructured lipid carriers (NLCs) have been reported to accumulate in inflamed colonic mucosa. The antioxidant/antiinflamatory polyphenol oleuropein (OLE) was loaded in NLCs (NLC-OLE). NLC-OLE showed to be more effective in decreasing the TNF-α secretion and intracellular reactive oxygen species (ROS) by activated macrophages (J774) compared to the conventional form of OLE. OLE efficacy was preserved within NLC-OLE ameliorating inflammation in a murine model of acute colitis: reduced levels of TNF-α and IL-6, decreased neutrophil infiltration and improved histopathology of the colon were reported. In addition, NLC-OLE enhanced the ROS scavenging activity of OLE in the colon after oral administration. These data suggest that the proposed NLC-OLE could be a promising drug delivery system for OLE in IBD treatment.
Subject(s)
Colitis/drug therapy , Drug Delivery Systems , Inflammation/drug therapy , Iridoids/administration & dosage , Administration, Oral , Animals , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/pharmacology , Antioxidants/administration & dosage , Antioxidants/pharmacology , Cell Line , Colitis/pathology , Disease Models, Animal , Drug Carriers/chemistry , Inflammation/pathology , Iridoid Glucosides , Iridoids/pharmacology , Lipids/chemistry , Macrophages/drug effects , Macrophages/pathology , Male , Mice , Mice, Inbred C57BL , Nanostructures , Oxidative Stress/drug effects , Reactive Oxygen Species/metabolismABSTRACT
Oxidative damage has been linked to a number of diseases. Oleuropein (OLE), a natural occurring polyphenol from olive leaves (Olea europaea L.), is known to be a potent antioxidant compound with inherent instability and compromised bioavailability. Therefore, in this work, nanostructured lipid carriers (NLCs) were proposed for OLE encapsulation to protect and improve its antioxidant efficacy. The lipid matrix, composed of olive oil and Precirol, was optimized prior to OLE encapsulation. The characterization of the optimized oleuropein-loaded NLCs (NLC-OLE) showed a mean size of 150 nm, a zeta potential of -21 mV, an encapsulation efficiency of 99.12%, sustained release profile, and improved radical scavenging activity. The cellular in vitro assays demonstrated the biocompatibility of the NLCs, which were found to improve and maintain OLE antioxidant efficacy in the A549 and CuFi-1 lung epithelial cell lines, respectively. Overall, these findings suggest a promising potential of NLC-OLE to further design a pulmonary formulation for OLE delivery in lung epithelia.
