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Sarcoglycan subcomplex is a transmembrane glycoprotein system which connects extracellular matrix to cytoskeleton. Although this complex has been found in several non-muscular tissues, no data exist about a sarcoglycan subcomplex in brain. Only the presence of ε-sarcoglycan in brain has been described in detail because its mutation determines Myoclonus Dystonia Syndrome. Also ζ-, β- and δ-sarcoglycans have been found in brain but only at mRNA level and their distribution in brain is still unknown. Here, we have searched for the expression of all sarcoglycans in specific brain regions of rat as hippocampus, cerebral and cerebellar cortex. Since a correlation between dystrophin glycoprotein complex and γ-amino butyric acid A (GABAA) receptor was demonstrated, we have investigated also a possible colocalization between sarcoglycans and GABAA receptor. Results have shown that all sarcoglycans are expressed in neurons of all observed regions; these proteins show a spot-like pattern of fluorescence and are mainly localized at soma level. Moreover, each sarcoglycan colocalizes with GABAA receptor. The present study shows, for the first time, the expression of all sarcoglycans in brain; moreover, the prevalent localization of sarcoglycans at post-synaptic level and the colocalization of these glycoproteins with GABAA receptor suggests that sarcoglycans play a key role in central nervous system, regulating post-synaptic receptors assembly., Italian Journal of Anatomy and Embryology, Vol 120, No 2 (2015)

The sarcoglycan sub-complex is a protein system which plays a key role in sarcolemma stabilization during muscle activity. Although numerous studies have been conducted on this system, there are few data about its localization in non-muscular tissues. On this basis we carried out an indirect immunofluorescence study on normal rat cerebral and cerebellar cortex. In particular, we carried out single localization reactions to analyze if these proteins are present in brain and double localization reactions between sarcoglycans and either SMI-32 or GFAP to verify if they are expressed both in neurons and glial cells. We found that all tested sarcoglycans are present both in cerebral and cerebellar cortex and that they are expressed both in neurons and glial cells. The typical staining pattern of all sarcoglycans is represented by “spot-like” fluorescence, with spots of 0.5-2 μm average diameter laid out mainly around the soma of the cells. The main difference about sarcoglycans expression between cerebral and cerebellar cortex is that in the cerebellar cortex the sarcoglycans positivity is detectable only in an area which is likely to correspond to Purkinje cells layer. The presence of sarcoglycans in cerebral and cerebellar cortex and their disposition mainly around the soma of the cells suggest a role of these proteins in cellular signalling and in regulating postsynaptic receptor assembly mainly in axo-somatic synapses., Italian Journal of Anatomy and Embryology, Vol 117, No 1 (2012)

The post-mortem assessment of sepsis-related death can be carry out by many methods recently suggested as microbiological and biochemical investigations. In these cases, the cause of death is a multiple organ dysfunction due to a dysregulated inflammatory response occurring after the failure of infection control process. It was highlighted also that the heart can be a target organ in sepsis which determines the so-called septic cardiomyopathy characterized by myocardial depression. Several mechanisms to explain the pathophysiology of septic cardiomyopathy were suggested, but very few studies about the structural alterations of cardiac cells responsible for myocardial depression were carried out. The aim of this study was to evaluate whether sarcoglycans (SG) were involved in septic cardiac damage analyzing their expression in sepsis-related deaths and, particularly, if these proteins can be used as markers of septic myocardial dysfunction. Cases of septic-related death confirmed by clinical and autopsy records were investigated and compared to a control group of traumatic deaths. Indirect immunofluorescence analysis was performed to analyze α-SG, β-SG, δ-SG, ζ-SG, ε-SG, and γ-SG. Decrease of fluorescence staining pattern for all tested sarcoglycans was observed in the septic-related deaths compared to normal fluorescence staining pattern of control group. These results provide new findings about the myocytes structural alterations due to sepsis and suggest that these proteins could be used in forensic assessment of septic cardiomyopathy.