Nose-to-brain delivery of insulin enhanced by radiation-engineered nanogels

Recent evidences suggest thet insulin delivery to the brain can be an important pharmacological therapy for some neurodegenerative pathologies, including Alzheimer disease (AD)

Hydrogel scaffolds based on k-Carrageenan/xyloglucan blends to host spheroids from human adipose stem cells

Hydrogels are water-swollen networks of hydrophilic polymer. They can be fabricated in various shapes and swell in water or aqueous solutions maintaining their original shape or undergo progressive erosion; can exibit large volume phase transitions with the change of one environmental parameter (stimuli-responsivness), shock absorption and low sliding friction properties (1). The morphology and mechanical properties of hydrogels are strongly affected by the network composition, the nature and degree of crosslinking and the degree of swelling. Indeed, when hydrogels are designed as scaffolds for human tissues remodeling, they must have sufficient mechanical integrity to provide support to th…

Idrogeli a base di xiloglucano e k-carragene con sferoidi di cellule staminali adipose umane come scaffolds per la medicina rigenerativa

Con l’obiettivo di sviluppare scaffold per la rigenerazione dei tessuti umani con sferoidi di cellule staminali adipose (S-ASC), questo lavoro indaga le proprietà degli idrogeli formati da dei polisaccaridi che subiscono transizioni sol-gel indotte dalla temperatura e le loro miscele: k-carragene (k-C) e xiloglucano parzialmente degalattosilato (Deg-XG). Gli idrogeli sono network polimerici idrofili rigonfiati dall'acqua. La morfologia e le proprietà meccaniche degli idrogeli sono fortemente influenzate dalla loro composizione, grado di reticolazione e di rigonfiamento. Quando sono progettati come scaffold, devono avere sufficiente integrità meccanica per fornire supporto alle cellule, dall…

Bryophytes: a powerful source of biologically active compounds

Bryophytes are generally considered the first plants appeared on the Earth. Taxonomically, they are placed between Algae and Pteridophytes. The medicinal traditional use of bryophytes has been documented for a long time in many countries. Bryophytes contain numerous potentially useful compounds and strong antioxidative enzymatic machinery, which help them to cope up with extreme climates and stresses, and, in several cases, the total antioxidant amount was found higher than in other antioxidant common sources even if not yet fully known. Thus, a positive correlation between the folklore use and the scientific evaluation could generate an alternative source of novel medicinal compounds, whic…

Adipose stem cell spheroids-laden hydrogels for minimally invasive bone and cartilage regeneration interventions

Xyloglucan-based hydrogel film for wound dressing: Structure and biological properties relationships

Crosslinked xyloglucan-poly(vinyl alcohol) based hydrogel films have been synthetized and characterized for wound healing applications. Polyvinyl alcohol (PVA) and glycerol (Gro) were added to have an optimal combination of softness, conformability and resilience. Physical hydrogel have been transformed into permanent covalent hydrogels by reaction with glutaraldehyde (GA). Chemical and physical properties of the films have been analyzed by different technique. Moreover, biocompatibility of a selected formulation was assessed in vitro by investigating different aspects, such as cell viability, oxidative stress, mitochondrial dysfunction and specific stress biomarkers. Partial adhesiveness w…

Agarose/k-Carrageenan-based hydrogel films enriched with natural extracts for wound healing applications

Hydrogels are 3D hydrophilic networks that can hold significant amounts of water within their structure, without dissolving in water.

Miscele di k-carragenina e PVA come bio-inchiostri per stampa 3D di scaffold per la ricostruzione della cartilagine

Introduzione La k-carragenina (kC) è un poligalattano solfato ottenuto da alghe rosse con un contenuto di estere-solfato dal 25 al 30% e una peso molecolare medio ben superiore a 100 kDa. È formato da unità alternate di D-galattosio e 3,6-anidro-galattosio (3,6-AG) unite da legami α-1,3 e β-1,4-glicosidici. [1] Il kC assomiglia ai glicosaminoglicani (GAG) che sono i costituenti centrali dei tessuti connettivi, può essere quindi studiato per produrre scaffold per l'ingegneria tissutale. Il kC è solubile in acqua a temperature superiori a 60 °C e può formare gel stabili raffreddandosi. Le reti di kC sono forti, fragili e l'assenza di porosità interconnesse può limitare la colonizzazione dell'…

Idrogeli con sferoidi di cellule staminali adipose per interventi mini-invasivi di rigenerazione ossea o cartilaginea

Introduzione Lo xiloglucano (XG) è un polisaccaride sia di struttura che di riserva, perché svolge il ruolo di matrice nelle pareti cellulari delle piante superiori ma è anche presente in alcuni semi, tra i quali tamarindo. Lo xiloglucano da semi di tamarindo è disponibile in commercio, è un polimero biocompatibile, approvato dalla FDA per uso alimentare. È caratterizzato da uno scheletro di β-(1, 4)-D-glucano parzialmente sostituito da α-(1, 6)-D-xilosio e β-(1, 2)-D-galattossilosio. La scissione enzimatica di alcuni dei residui di galattosio fornisce allo XG proprietà di gelificazione indotte da variazioni di temperatura. In particolare, quando viene rimosso il 35% circa dei residui di ga…

Macromolecular engineering of hydrogels: from macro to nano scalar materials for different levels of biointeraction

Exploring nose-to-brain insulin delivery as a new strategy for the treatment of Alzheimer’s disease

A growing body of evidence shows that Insulin, Insulin Receptor (IR) and IR signaling are involved in brain cognitive functions and their dysfunction is implicated in Alzheimer’s disease (AD) degeneration. Thus, administration of insulin could be a strategy for AD treatment. For this aim we designed, synthesized and characterized a nanogel system (NG) to deliver insulin to the brain, as a tool for the development of a new therapy for AD. A carboxyl-functionalized poly(N-vinyl pyrrolidone) nanogel system produced by high energy ionizing radiation was chosen as substrate for the covalent attachment of insulin or fluorescent molecules, relevant for its tracing

Studies of network organization and dynamics of e-beam crosslinked PVPs: From macro to nano

Abstract In this work the influence of poly(N-vinyl pyrrolidone) (PVP) concentration in water on the organization and dynamics of the corresponding macro-/nanogel networks has been systematically investigated. Irradiation has been performed at the same irradiation dose (within the sterilization dose range) and dose rate. In the selected irradiation conditions, the transition between macroscopic gelation and micro-/nanogels formation is observed just below the critical overlap concentration (∼1 wt%), whereas the net prevalence of intra-molecular over inter-molecular crosslinking occurs at a lower polymer concentration (below 0.25 wt%). Dynamic–mechanical spectroscopy has been applied as a cl…

Injectable hydrogel formulations to host adipose stem cell spheroids for stemness maintenance and bone and cartilage regeneration

Adipose-derived mesenchymal stem cells (ASCs) represent a great promise for tissue regeneration as fat is a very abundant source of stem cells (1) and owing to their ability to self-renew and differentiate into specific tissue types (2). In general, they are usually cultured as two-dimensional (2D) adherent monolayers, not representative of the in vivo condition, often entailing lower cell viability and, more in general, a lower “cell quality” in terms of regenerative potential (3, 4). When ASCs are cultured in low adhesion flasks and with a suitable culture medium, they aggregate in the form of three-dimensional spheroids (SASCs). The incorporation of these spheroids into injectable, in-si…

k-Carrageenan and PVA blends as 3D printing bioinks for cartilage reconstruction scaffolding

Development and characterization of xyloglucan-poly(vinyl alcohol) hydrogel membrane for wireless smart wound dressings

Research which addresses advanced wound management can contribute to the needs of modern healthcare, especially in situations that require continuous monitoring, analysis, responsive therapeutic treatments and data recording. The development of “smart” bandages and dressings that can remotely monitor relevant parameters for the wound healing process without a hospital intervention can be very useful tools for patients and physicians and for advancing the understanding of the healing process. In the present work, biocompatible xyloglucan/poly(vinyl alcohol) hydrogels are being developed as smart wound dressings that, in addition to the traditional favorable properties of hydrogels as skin ca…