Muscle LIM protein/CSRP3: a mechanosensor with a role in autophagy.

Muscle LIM protein (MLP) is a microtubule-associated protein expressed in cardiac and muscle tissues that belongs to the cysteine-rich protein (CSRP/CRP) family. MLP has a central role during muscle development and for architectural maintenance of muscle cells. However, muscle cells rely on autophagy during differentiation and for structural maintenance. To study the role of MLP in autophagy, we have used C2C12 mouse myoblasts silenced or overexpressing MLP. Our results show that MLP contributes to the correct autophagosome formation and flux by interacting with LC3 as demonstrated by co-immunoprecipitation and PLA assay. In fact, MLP silencing results in decreased LC3-II staining and absent degradation of long-lived proteins. Moreover, MLP silencing impaired myoblasts differentiation as measured by decreased expression of MyoD1, MyoG1 and myosin heavy chain. Ultrastructural analysis revealed the presence of large empty autophagosomes in myoblasts and multimembranous structures in myotubes from MLP-silenced clones. Impaired autophagy in MLP-silenced cells resulted in increased susceptibility to apoptotic cell death. In fact, treatment of MLP-silenced C2C12 myoblasts and myotubes with staurosporine resulted in increased caspase-3 and PARP cleavage as well as increased percentage of cell death. In conclusion, we propose that MLP regulates autophagy during muscle cell differentiation or maintenance through a mechanism involving MLP/LC3-II interaction and correct autophagosome formation.

[Regional changes in endothelin levels in venous and arterial blood in a limb subjected to postural variations]. / Modificazioni distrettuali dell'endotelina a livello del sangue venoso e arterioso in un arto sottoposto a variazioni posturali.

The aim of this study was to evaluate the behaviour of plasma endothelin in humans both in venous and arterial blood at the level of a limb subjected to postural changes. An experimental model was designed for this purpose in which tissue hypoperfusion conditions were created in a subject lying on his back by maintaining an upper limb in a vertical position for approximately one hour. The limb was then lowered and remained horizontal for another hour. The study was performed in 5 healthy subjects aged between 59 and 75 years old. Both venous and arterial blood samples were collected, virtually contemporaneously, at times 0.60 and 120 minutes, namely before and after raising the limb and after the limb had been lowered for one hour. Mean endothelin levels +/- SD in arterial blood were respectively 3.36 +/- 1.29 pg/ml, 4.13 +/- 1.16 pg/ml and 3.82 +/- 1.11 pg/ml at times 0.60 and 120 min. Mean endothelin levels SD in venous blood at the same times were respectively 3.84 +/- 1.41 pg/ml, 5.62 +/- 2.26 pg/ml and 4.95 +/- 1.39 pg/ml. In both arterial and venous blood, the difference between the first two values was statistically significant (p < 0.05). Endothelin therefore appears to be affected by changes in district hemodynamics.

[Multiorgan failure syndrome in multiple pregnancy gestosis]. / Sindrome da insufficienza multiorganica in gestosi gravidica plurigemellare.

The Authors report a clinical case of Multi Organ Failure in a young woman who had given birth to triplets. After a short recall of Multi Organ Failure Syndrome, the Authors describe the clinical course and the therapy used in this case.

[Anesthesia in percutaneous discectomy by the Onik's technique]. / L'anestesia nella discectomia percutanea secondo Onik.

The type of anaesthesia used in percutaneous discectomy, a new technique for treating slipped disc, is described. The personal series consist of 960 patients. In 768, local anaesthesia by infiltration of the anatomical trajectory was used as a follow-up to nucleotome. In the rest, general anaesthesia was used. Conclusion are drawn from the comparison.