Expression of phosphoinositide‐specific phospholipase C isoenzymes in cultured astrocytes

Abstract

Signal transduction from plasma membrane to cell nucleus is a complex process depending on various components including lipid signaling molecules, in particular phosphoinositides and their related enzymes, which act at cell periphery and/or plasma membrane as well as at nuclear level. As far as the nervous system may concern the inositol lipid cycle has been hypothesized to be involved in numerous neural as well as glial functions. In this context, however, a precise panel of glial PLC isoforms has not been determined yet. In the present experiments we investigated astrocytic PLC isoforms in astrocytes obtained from foetal primary cultures of rat brain and from an established cultured (C6) rat astrocytoma cell line, two well known cell models for experimental studies on glia. Identification of PLC isoforms was achieved by using a combination of RT-PCR and immunocytochemistry experiments. While in both cell models the most represented PI-PLC isoforms were beta4, gamma1, delta4, and epsilon, isoforms PI-PLC beta2 and delta3 were not detected. Moreover, in primary astrocyte cultures PI-PLC delta3 resulted well expressed in C6 cells but was absent in astrocytes. Immunocytochemistry performed with antibodies against specific PLC isoforms substantially confirmed this pattern of expression both in astrocytes and C6 glioma cells. In particular while some isoenzymes (namely isoforms beta3 and beta4) resulted mainly nuclear, others (isoforms delta4 and epsilon) were preferentially localized at cytoplasmic and plasma membrane level.

LPS, Oleuropein and Blueberry extracts affect the survival, morphology and Phosphoinositide signalling in stimulated human endothelial cells

“…Confirming our previous works (Lo Vasco et al 2007;Lo Vasco et al 2013a, b, c), LPS administration to HUVEC cultures significantly reduced the number of live cells, especially in the 0-3 h interval (Fig. 1, Tables 2 and 3).…”

Comparison of Phosphoinositide-Specific Phospholipase C Expression Panels of Human Osteoblasts Versus MG-63 and Saos Osteoblast-Like Cells

“…PLC enzymes are described as highly tissue-specific in normal tissues (18,19,21). However, the PLC expression panels in tissues vary under abnormal conditions compared to normal counterparts (20,21,23,24,(26)(27)(28).…”

“…Knowledge of the expression panels of PI-PLC enzymes is a necessary and preliminary tool to address studies about their role in quiescent cells. Moreover, the expression panels of PI-PLC enzymes have been demonstrated to differ in quiescent cells with respect to the pathological or activated counterpart (18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30).…”

Phosphoinositide pathway and the signal transduction network in neural development

“…PI-PLC enzymes are also involved in the inflammatory activation of glia [41] . Recently, the involvement of PI-PLC isoforms in the aetiopathogenesis of rat astrocytoma [42] and in human neuroblastoma has been raised [41] .…”

“…Intriguingly, differential expression of PI-PLC isoforms has been detected in normal with respect to pathological tissues, mainly tumours [42] .…”