Activation of Rac1-dependent redox signaling is critically involved in staurosporine-induced neurite outgrowth in PC12 cells

Abstract

Staurosporine, a non-specific protein kinase inhibitor, has been shown to induce neurite outgrowth in PC12 cells, but the mechanism by which staurosporine induces neurite outgrowth is still obscure. In the present study, we investigated whether the activation of Rac1 was responsible for the neurite outgrowth triggered by staurosporine. Staurosporine caused rapid neurite outgrowth independent of the ERK signaling pathways. In contrast, neurite outgrowth in response to staurosporine was accompanied by activation of Rac1, and the Rac1 inhibitor NSC23766 attenuated the staurosporine-induced neurite outgrowth in a concentration-dependent manner. In addition, suppression of Rac1 activity by expression of the dominant negative mutant Rac1N17 also blocked the staurosporine-induced morphological differentiation of PC12 cells. Staurosporine caused an activation of NADPH oxidase and increased the production of reactive oxygen species (ROS), which was prevented by NSC23766 and diphenyleneiodonium (DPI), an NADPH oxidase inhibitor. Staurosporine-induced neurite outgrowth was attenuated by pretreatment with DPI and exogenous addition of sublethal concentration of H2O2 accelerated neurite outgrowth triggered by staurosporine. These results indicate that activation of Rac1, which leads to ROS generation, is required for neurite outgrowth induced by staurosporine in PC12 cells.

Y-27632 Induces Neurite Outgrowth by Activating the NOX1-Mediated AKT and PAK1 Phosphorylation Cascades in PC12 Cells

“…As shown in Figure 1 A, Y-27632 effectively induced neurite outgrowth in PC12 cells in a dose- and time-dependent manner. Previously, ROS generation was shown to be involved in the neuritogenesis of PC12 cells [ 21 , 22 , 23 ]. To test whether the production of ROS contributed to Y-27632-induced neurite outgrowth, we first measured cellular ROS levels using the membrane permeable fluorescent probe DCF-DA in cells that were exposed to Y-27632.…”

Quinolinic acid induces neuritogenesis in SH‐SY5Y neuroblastoma cells independently of NMDA receptor activation

“…Even the use of antioxidant compounds can lead to conflicting results with some authors demonstrating the promotion of neurite production (Weinreb et al ., ) while others see a suppression (Munnamalai & Suter, ; Wilson & Gonzalez‐Billault, ). Differentiation and neurite formation in PC12 phaeochromocytoma cells appears to be substantially dependent on the presence of ROS (Kotake‐Nara & Saida, , ; Kim et al ., ). The present observations with QA are therefore entirely consistent with this earlier body of work.…”

In vitro models for neurotoxicology research

“…Thrice cloned subline of SK-N-SH cells 146 Expresses DAT 148,150,151 Expresses DA-β-hydroxylase and TH 504 After differentiation, presents a functionally mature neuronal phenotype 147,148 Limited synthesis of catecholamines (DA and NA) as a result of the deficiency in dihydroxyphenylalanine decarboxylase 504 Exhibits specific uptake of NA 503 Expresses proteins of NFs 503 Expresses opioid, muscarinic, and nerve growth factor (NGF) receptors 503 May differentiate upon treatment with a variety of agents [147][148][149][150][151][152][153][154][155] or substrates' deprivation 151,156,157 PC12 cell line Established from a rat pheochromocytoma 187 Expresses receptors coupled to G-proteins 191 Expresses AChE, ChAT and ACh synthase 505 May differentiate upon treatment with a variety of agents 186,189,[191][192][193][194][197][198][199] Low DA-β-hydroxylase activity 187 Expresses Na + , K + , and Ca 2+ channels 191 Ability to synthesize and store ADR and DA, and sometimes NA, which may be released upon depolarization in a Ca 2+ -dependent manner 190 Difficulty in adherence to tissue culture plates 200 C6 cell line Express Ras, Ras GTP activator protein…”