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Mesenchymal Stem Cells (MSCs) are effective therapeutic agents enhancing the repair of injured tissues mostly through their paracrine activity. Increasing evidences show that besides the secretion of soluble molecules, the release of extracellular vesicles (EVs) represents an alternative mechanism adopted by MSCs. Since macrophages are essential contributors toward the resolution of inflammation, which has emerged as a finely orchestrated process, the aim of the present study was to carry out a detailed characterization of EVs released by human adipose derived‐MSCs to investigate their involvement as modulators of MSC anti‐inflammatory effects inducing macrophage polarization. The EV‐isolation method was based on repeated ultracentrifugations of the medium conditioned by MSC exposed to normoxic or hypoxic conditions (EVNormoand EVHypo). Both types of EVs were efficiently internalized by responding bone marrow‐derived macrophages, eliciting their switch from a M1 to a M2 phenotype. In vivo, following cardiotoxin‐induced skeletal muscle damage, EVNormoand EVHypointeracted with macrophages recruited during the initial inflammatory response. In injured and EV‐treated muscles, a downregulation of IL6 and the early marker of innate and classical activation Nos2 were concurrent to a significant upregulation of Arg1 and Ym1, late markers of alternative activation, as well as an increased percentage of infiltrating CD206poscells. These effects, accompanied by an accelerated expression of the myogenic markers Pax7, MyoD, and eMyhc, were even greater following EVHypoadministration. Collectively, these data indicate that MSC‐EVs possess effective anti‐inflammatory properties, making them potential therapeutic agents more handy and safe than MSCs. StemCellsTranslationalMedicine2017StemCellsTranslationalMedicine2017;6:1018–1028

In Regenerative Medicine, platelet by-products containing factors physiologically involved in wound healing, have been successfully used in the form of platelet-rich plasma (PRP) for the topical therapy of various clinical conditions since it produces an improvement in tissue repair as well as analgesic effects. Measurement of endocannabinoids and related compounds in PRP revealed the presence of a significant amount of anandamide, 2-arachidonoylglycerol, palmitoylethanolamide, and oleoylethanolamide. Investigation of the activity of PRP on the keratinocyte cell line NCTC2544 in physiological and inflammatory conditions showed that, under inflammatory conditions, PRP induced in a statistically significant manner the production of these compounds by the cells suggesting that PRP might induce the production of these analgesic mediators particularly in the physiologically inflamed wounded tissue. Studies in a mouse model of acute inflammatory pain induced by formalin injection demonstrated a potent antinociceptive effect against both early and late nocifensive responses. This effect was observed following intrapaw injection of (1) total PRP; (2) lipids extracted from PRP; and (3) an endocannabinoid-enriched lipid fraction of PRP. In all conditions, antagonists of endocannabinoid CB1 and CB2 receptors, injected in the paw, abrogated the antinociceptive effects strongly suggesting for this preparation a peripheral mechanism of action. In conclusion, we showed that PRP and PRP lipid extract exert a potent antinociceptive activity linked, at least in part, to their endocannabinoids and related compound content, and to their capability of elevating the levels of these lipid mediators in cells.

Platelet lysates (PL), which are derived from platelets, are cocktails of growth factors and cytokines that can promote tissue regeneration. Until today, most studies have focused on growth factor content of platelets rather than on their potential as a reservoir of mediators and cytokines. Taking advantage of an in vitroscratch assay performed under both normal and inflammatory conditions, in the present work, we report that at physiologic concentrations, PL enhanced wound closure rates of NCTC 2544 human keratinocytes. This effect was clearly detectable 6 h after wounding. Moreover, PL induced a strong cell actin cytoskeletal re-organization that persisted up to 24 h. The accelerated wound closure promoted by PL, in either presence or absence of serum, was associated with a high expression of the inflammatory cytokine interleukin-8. Further, after 24 h PL treatment, confluent keratinocytes also expressed low amounts of interleukin-8 and of the antimicrobial peptide neutrophil gelatinase-associated lipocalin, which dramatically increased under inflammatory conditions. These effects were associated with activation of the inflammatory pathways, p38 mitogen-activated protein kinase, and NF-κB. Our findings support the concept that platelet-derived preparations could accelerate regeneration of difficult-to-heal wounds by triggering an inflammatory cascade and having an antimicrobial role.

During the second phase of osteogenesis in vitro, rat osteoblasts secrete inducer(s) of chemotaxis and chemoinvasion of endothelial and tumor cells. We report here the characterization and purification from mature osteoblast conditioned medium of the agent chemotactic for endothelial cells. The chemoactive conditioned medium specifically induces directional migration of endothelial cells, not affecting the expression and activation of gelatinases, cell proliferation, and scattering. Directional migration induced in endothelial cells by conditioned medium from osteoblasts is inhibited by pertussis toxin, by blocking antibodies to integrins α1, β1, and β3, and by antibodies to metalloproteinase 2 and 9. The biologically active purified protein has two sequences, coincident with the amino-terminal amino acids, respectively, of the α1and of the α2carboxyl propeptides of type I collagen, as physiologically produced by procollagen C proteinase. Antibodies to type I collagen and to the carboxyl terminus of α1or α2chains inhibit chemotaxis. The chemoattractant is the propeptide trimer carboxyl-terminal to type I collagen, and its activity is lost upon reduction. These data illustrate a previously unknown function for the carboxyl-terminal trimer, possibly relevant in promoting endothelial cell migration and vascularization of tissues producing collagen type I.

In recent years echocardiography has become a good diagnostic tool in Zoo Medicine but in some cases, it is still a challenge. In Aldabra giant tortoise (Aldabrachelys gigantea) the big size of animals and the few individuals hosted in Zoo are critical points for the application of this diagnostic technique. The purposes of this research were: to evaluate the feasibility of the diagnostic imaging technique on big-sized turtles; to define the echographic parameters for this species; and to describe the morphofunctional and physiological echographic characteristics of their cardiovascular system. Repeated measures in vivo. Ultrasonography systematic description and Doppler analysis of the cardiovascular system of Aldabra giant tortoise were carried out; B-mode examination allowed the evaluation of the kinetics of the ventricle, the atria and the atrioventricular valves. 4 Aldabra giant tortoises (two adult males and two young females) hosted in two zoological gardens. Echocardiography was performed placing the animals in ventral on a restraining platform raised from the floor, to provide adequate accessibility to the thoracic windows where the probe was placed. No chemical restraint was used. Heart rate, systolic and diastolic areas and volumes, vessel diameters and blood flow velocity were measured. Heart rate was 21±4 bpm (range 14–25 bpm). The averages of the diastolic and systolic area indexes linked to the subject weight were: 21±3 cm2and 9±1 cm2. The aortic annulus diameter in female specimens measured 11.2±0.8 mm, while it measured 21.5±0.3 mm in male species. Results confirm the effectiveness of echocardiography as a means to study and evaluate the cardiovascular system of this species even if more studies on a bigger number of patients would be necessary to develop the echocardiography technique.

The mono- and digalactosyldiacylglycerol (MGDG and DGDG) galactolipids have been purified from the thermophilic blue-green alga Phormidium sp. ETS-05 that colonizes the therapeutic thermal mud of Abano Terme and Montegrotto Terme, Italy. Both compounds present a marked composition in polyunsaturated fatty acids, mainly omega-3. The therapeutic thermal mud is applied mainly to osteoarthritic cartilage patients. In the present study the effect of MGDG treatment on proteins and factors expressed by human articular cartilage cells in culture and on pathways activated in inflammatory conditions was studied.