Angiotensin II Induces Differentiation of Human Neuroblastoma Cells by Increasing MAP2 and ROS Levels.

Introduction: The roles of angiotensin II (Ang II) in the brain are still under investigation. In this study, we investigated if Ang II influences differentiation of human neuroblastoma cells with simultaneous activation of NADPH oxidase and reactive oxygen species (ROS). Moreover, we investigated the Ang II receptor type involved during differentiation.

Methods: Human neuroblastoma cells (SH-SY5Y; 5 × 10⁵ cells) were exposed to Ang II (600 nM) for 24 h. Differentiation was monitored by measuring MAP2 and NF-H levels. Cell size and ROS were analyzed by flow cytometry, and NADPH oxidase activation was assayed using apocynin (500 μM). Ang II receptors (ATR) activation was assayed using ATR blockers or Ang II metabolism inhibitors (10^-7 M).

Results: (1) Cell size decreased significantly in Ang II-treated cells; (2) MAP2 and ROS increased significantly in Ang II-treated cells with no changes in viability; (3) MAP2 and ROS decreased significantly in cells incubated with Ang II plus apocynin. (4) A significant decrease in MAP2 was observed in cells exposed to Ang II plus PD123.319 (AT2R blocker).

Conclusion: Our findings suggest that Ang II influences differentiation of SH-SY5Y by increasing MAP2 through the AT2R. The increase in MAP2 and ROS were also mediated through NADPH oxidase with no cell death.