Peroxynitrite modulates tyrosine phosphorylation and phosphoinositide signalling in human neuroblastoma SH-SY5Y cells: attenuated effects in human 1321N1 astrocytoma cells

Abstract

Peroxynitrite may contribute to oxidative stress involving neurodegeneration in several disorders, including Alzheimer's disease. As with other reactive oxygen species, peroxynitrite might affect neuronal signalling systems, actions that could contribute to adaptive or deleterious cellular outcomes, but such effects have not previously been studied. To address this issue directly, peroxynitrite (50-500 microM) was administered to human neuroblastoma SH-SY5Y cells to assess its effects on protein tyrosine nitration, phosphoinositide signalling and protein tyrosine phosphorylation. Peroxynitrite rapidly increased the nitrotyrosine immunoreactivity of numerous proteins, primarily in the cytosol. Peroxynitrite inhibited, in a concentration-dependent manner, phosphoinositide hydrolysis stimulated by activation of muscarinic receptors with carbachol and the inhibition was greater after the depletion of cellular glutathione. In comparison, muscarinic receptor-stimulated phosphoinositide hydrolysis in human astrocytoma 1321N1 cells was less vulnerable to inhibition by peroxynitrite either without or with prior depletion of glutathione. There was a large, rapid and reversible increase in the tyrosine phosphorylation of the p120 Src substrate in peroxynitrite-treated SH-SY5Y cells, a response that was potentiated by glutathione depletion; in contrast, peroxynitrite decreased the tyrosine phosphorylation of focal adhesion kinase and paxillin. Tyrosine phosphorylation of p120 in 1321N1 astrocytoma cells was less sensitive to modulation by peroxynitrite. Thus alterations in phosphoinositide signalling and protein tyrosine phosphorylation were greater in neuroblastoma than astrocytoma cells, and modulation of these signalling processes probably contributes to neuronal mechanisms of the response to peroxynitrite.

Nitrite–dependent nitric oxide production pathway: implications for involvement of active nitrogen species in photoinhibitionin vivo

“…Protein nitration would interfere with enzyme functions or metabolism. In animal systems, the formation of nitrotyrosine has been reported to disturb signal transduction systems by inhibiting the phosphorylation^dephosphoryla-tion process of proteins (Kong et al 1996;Li et al 1998). Figure 8 summarizes the two pathways for NO production in leaves.…”

Selective Scavenging Property of the Indole Moiety for the Nitrating Species of Peroxynitrite

“…[5][6][7][8][9][10][11][12][13][14][15][16][17] These data imply that the oxidizing and nitrating reactions of PN may play different pathological roles in the oxidative stress process. From this point of view, it is very useful and important to discriminate the reaction of nitrating (nitrative) damage from that of the oxidative damage in PN-induced oxidative stress reactions.…”

1–40 β‐amyloid protein fragment modulates the expression of CD44 and CD71 on the astrocytoma cell line in the presence of IL1β and TNFα

“…To verify this hypothesis, we utilised the 1321N1 astrocytoma-derived cell line as an experimental model (Trejo et al, 1994;Li et al, 1998;Bourke and Moynagh, 1999) to study the modulation of CD44, VCAM-1 or CD71 after treatment with two different cytokines, IL1b and TNFa, and the amyloid-b (Ab) fragments, that are largely present in amyloid plaques. The results Overall, IL1b appears to be a stronger signal for human astrocytes compared to TNFa.…”

“…As control, classical astrocyte activators, IL1b and TNFa, were used. The human astrocytoma 1321N1 cell line has been chosen since it represents a useful and reliable model to study the properties of astrocyte and their response to immunological stimulation (Trejo et al, 1994;Li et al, 1998;Bourke and Moynagh, 1999).…”