C2C12 MYOBLASTS RELEASE MICRO-VESICLES CONTAINING mtDNA AND PROTEINS INVOLVED IN SIGNAL TRANSDUCTION

none11Micro-vesicles can be released by different cell types and operate as ‘safe containers’ mediatine inter-cellular communication. In this work we investigated whether cultured myoblasts could release exosomes. The reported data demonstrate, for the first time, that C2C12 myoblasts release micro-vesicles as shown by the presence of two exosome markers (Tsg101 and Alix proteins). Using real-time PCR analysis it was shown that these micro-vesicles, like other cell types, carry mtDNA. Proteomic characterization of the released micro-vesicle contents showed the presence of many proteins involved in signal transduction. The bioinformatics assessment of the Disorder Index and Aggregation Index of these proteins suggested that C2C12 micro-vesicles mainly deliver the machinery for signal transduction to target cells rather than key proteins involved in hub functions in molecular networks. The presence of IGFBP-5 in the purified micro-vesicles represents an exception, since this binding protein can play a key role in the modulation of the IGF-1 signalling pathway. In conclusion, the present findings demonstrate that skeletal muscle cells release micro-vesicles, which probably have an important role in the communication processes within skeletal muscles and between skeletal muscles and other organs. In particular, the present findings suggest possibile new diagnostic approaches to skeletal muscle diseases.openM. GUESCINI; D. GUIDOLIN; L. VALLORANI; L. CASADEI; A.M. GIOACCHINI; P. TIBOLLO; M. BATTISTELLI; E. FALCIERI; L. BATTISTIN; L.F. AGNATI; V. STOCCHIGuescini, Michele; D., Guidolin; Vallorani, Luciana; Casadei, Lucia; Gioacchini, ANNA MARIA; P., Tibollo; Battistelli, Michela; Falcieri, Elisabetta; L., Battistin; L. F., Agnati; Stocchi, Vilbert

Multislice computed tomography overestimates superior semicircular canal dehiscence syndrome

OBJECTIVES: We assessed the prevalence of superior semicircular canal dehiscence (SSCD) through examination of ultrahigh-resolution computed tomography (CT) scans of the temporal bone and attempted to verify the correspondence between a radiologic diagnosis of SSCD and clinical signs of SSCD syndrome. METHODS: A prospective study was carried out on 191 consecutive patients who underwent temporal bone ultrahigh-resolution CT scans. Cases that matched the radiologic diagnosis of SSCD were subsequently referred for a comprehensive audiological evaluation that might enable a final diagnosis of SSCD syndrome. RESULTS: Among the 191 patients, 17 had a radiologic diagnosis of SSCD, which was bilateral in 5 cases, for a total of 22 SSCD cases, with a prevalence rate of 5.8%. In 2 of the 17 patients, the audiological examination revealed signs and symptoms indicative of SSCD syndrome, with a total prevalence rate of 0.5%. CONCLUSIONS: Our data confirm that the radiologic diagnosis of SSCD, performed by mean thin-section CT scans reformatted in the plane of the superior semicircular canal, is not necessarily related to the clinical presentation of SSCD syndrome. Our study also showed a prevalence rate of SSCD syndrome that was similar to the prevalence of SSCD reported from studies of histologic specimens

Calsequestrin Deletion Facilitates Hippocampal Synaptic Plasticity and Spatial Learning in Post-Natal Development

Experimental evidence highlights the involvement of the endoplasmic reticulum (ER)-mediated Ca2+ signals in modulating synaptic plasticity and spatial memory formation in the hippocampus. Ca2+ release from the ER mainly occurs through two classes of Ca2+ channels, inositol 1,4,5-trisphosphate receptors (InsP3Rs) and ryanodine receptors (RyRs). Calsequestrin (CASQ) and calreticulin (CR) are the most abundant Ca2+-binding proteins allowing ER Ca2+ storage. The hippocampus is one of the brain regions expressing CASQ, but its role in neuronal activity, plasticity, and the learning processes is poorly investigated. Here, we used knockout mice lacking both CASQ type-1 and type-2 isoforms (double (d)CASQ-null mice) to: a) evaluate in adulthood the neuronal electrophysiological properties and synaptic plasticity in the hippocampal Cornu Ammonis 1 (CA1) field and b) study the performance of knockout mice in spatial learning tasks. The ablation of CASQ increased the CA1 neuron excitability and improved the long-term potentiation (LTP) maintenance. Consistently, (d)CASQ-null mice performed significantly better than controls in the Morris Water Maze task, needing a shorter time to develop a spatial preference for the goal. The Ca2+ handling analysis in CA1 pyramidal cells showed a decrement of Ca2+ transient amplitude in (d)CASQ-null mouse neurons, which is consistent with a decrease in afterhyperpolarization improving LTP. Altogether, our findings suggest that CASQ deletion affects activity-dependent ER Ca2+ release, thus facilitating synaptic plasticity and spatial learning in post-natal development

Sintesi micorrizica in vitro fra piante forestali e funghi del genere Tuber: un modello per lo studio dei meccanismi morfologici e molecolari coinvolti nel processo di micorrizazione

none12mixedGIOMARO G; SISTI D.; AMICUCCI A; GUIDI C; MENOTTA M; POLIDORI E; PIERLEONI R; ZEPPA S; GIOACCHINI AM; GUESCINI M; STOCCHI V.; Donati Zeppa, S.Giomaro, Giovanna; Sisti, Davide; Amicucci, Antonella; Guidi, C; Menotta, Michele; Polidori, Emanuela; Pierleoni, R; Zeppa, S; Gioacchini, ANNA MARIA; Guescini, Michele; Stocchi, Vilberto; DONATI ZEPPA, Sabrin