Platelet-rich plasma (PRP) is a platelet concentrate in a small volume of plasma. It is highly enriched in growth factors able to stimulate the migration and growth of bone-forming cells. PRP is often used in clinical applications, as dental surgery and fracture healing. Platelet derived growth factor (PDGF), is highly concentrated in PRP and it was shown in our previous studies to provide the chemotactic stimulus to SaOS-2 osteoblasts to move in a microchemotaxis assay. Aim of the present studies is to analyze the effects of a PRP pretreatment (short time course: 30-150 min) of SaOS-2 cells with PRP on the organization of actin cytoskeleton, the main effector of cell mobility. The results indicate that a pretreatment with PRP increases chemokinesis and chemotaxis and concomitantly induces the organization of actin microfilaments, visualized by immunocytochemistry, in a directionally elongated phenotype, which is characteristic of the cells able to move. PRP also produces a transient increase in t...

Wound healing is a very complex process that allows organisms to survive injuries. It is strictly regulated by a number of biochemical and physical factors, mechanical forces included. Studying wound healing in space is interesting for two main reasons: (i) defining tools, procedures, and protocols to manage serious wounds and burns eventually occurring in future long-lasting space exploration missions, without the possibility of timely medical evacuation to Earth; (ii) understanding the role of gravity and mechanical factors in the healing process and scarring, thus contributing to unravelling the mechanisms underlying the switching between perfect regeneration and imperfect repair with scarring. In the study presented here, a new in vivo sutured wound healing model in the leech (Hirudo medicinalis) has been used to evaluate the effect of unloading conditions on the healing process and the effectiveness of platelet rich plasma (PRP) as a countermeasure. The results reveal that microgravity caused a healing delay and structural alterations in the repair tissue, which were prevented by PRP treatment. Moreover, investigating the effects of microgravity and PRP on an in vitro wound healing model, it was found that PRP is able to counteract the microgravity-induced impairment in fibroblast migration to the wound site. This could be one of the mechanisms underlying the effectiveness of PRP in preventing healing impairment in unloading conditions.

Hearing loss (HL) is the most common and heterogeneous disorder of the sensory system, with a large morbidity in the worldwide population. Among cells of the acoustic nerve (VIII cranial nerve), in the cochlea are present the hair cells, the spiral ganglion neurons, the glia-like supporting cells, and the Schwann cells (SCs), which alterations have been considered cause of HL. Notably, a benign SC-derived tumor of the acoustic nerve, named vestibular schwannoma (VS), has been indicated as cause of HL. Importantly, SCs are the main glial cells ensheathing axons and forming myelin in the peripheral nerves. Following an injury, the SCs reprogram, expressing some stemness features. Despite the mechanisms and factors controlling their biological processes (i.e., proliferation, migration, differentiation, and myelination) have been largely unveiled, their role in VS and HL was poorly investigated. In this review, we enlighten some of the mechanisms at the base of SCs transformation, VS development, and progression, likely leading to HL, and we pose great attention on the environmental factors that, in principle, could contribute to HL onset or progression. Combining the biomolecular bench-side approach to the clinical bedside practice may be helpful for the diagnosis, prediction, and therapeutic approach in otology.

Neuropathic pain arises as a direct consequence of a lesion or disease affecting the peripheral somatosensory system. It may be associated with allodynia and increased pain sensitivity. Few studies correlated neuropathic pain with nerve morphology and myelin proteins expression. Our aim was to test if neuropathic pain is related to nerve degeneration, speculating whether the modulation of peripheral GABA-B receptors may promote nerve regeneration and decrease neuropathic pain. We used the partial sciatic ligation- (PSL-) induced neuropathic model. The biochemical, morphological, and behavioural outcomes of sciatic nerve were analysed following GABA-B ligands treatments. Simultaneous 7-days coadministration of baclofen (10 mg/kg) and CGP56433 (3 mg/kg) alters tactile hypersensitivity. Concomitantly, specific changes of peripheral nerve morphology, nerve structure, and myelin proteins (P0 and PMP22) expression were observed. Nerve macrophage recruitment decreased and step coordination was improved. The PSL-induced changes in nociception correlate with altered nerve morphology and myelin protein expression. Peripheral synergic effects, via GABA-B receptor activation, promote nerve regeneration and likely ameliorate neuropathic pain.

Intense physical activity and dieting are core symptoms of anorexia nervosa (AN). Their combination evolves into compulsivity, leading the patient into an out-of-control spiral. AN patients exhibit an altered activation of nucleus accumbens (NAc), revealing a dysfunctional mesocorticolimbic reward circuitry in AN. Since evidence exists that a dysregulation of the glutamate system in the NAc influences reward and taking advantage of the activity-based anorexia (ABA) rat model, which closely mimics the hallmarks of AN, we investigated the involvement of the glutamatergic signaling in the NAc in this experimental model. We here demonstrate that food restriction causes hyperactive and compulsive behavior in rodents, inducing an escalation of physical activity, which results in dramatic weight loss. Analysis of the glutamate system revealed that, in the acute phase of the pathology, ABA rats increased the membrane expression of GluA1 AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor subunits together with its scaffolding protein SAP97. Recovery of body weight reduced GluN2A/2B balance together with the expression of their specific scaffolding proteins, thus suggesting persistent maladaptive neurotransmission. Taken together, AMPA and NMDA (N-methyl-D-aspartate) receptor subunit reorganization may play a role in the motivational mechanisms underlying AN.