Staurosporine induces apoptosis and necroptosis in cultured rat astrocytes

Abstract

Apoptosis and necroptosis are highly regulated, interconnected forms of a cell death. The distinction between them is critical, because necroptosis may cause significant cell loss and local inflammation, whereas apoptosis is essential for tissue homeostasis. The same stimulus can induce both apoptosis and necroptosis. Both forms of a cell death were detected in various pathologies, including pathologies in the central nervous system. Astrocytes are a large, heterogeneous cell population in the central nervous system, with many supportive, developmental functions. Although their demise may seriously impair normal functions of the central nervous system, it is still poorly understood. In this study, apoptosis and necroptosis were induced in cultured rat astrocytes by staurosporine. When a low concentration (10⁻⁷ M) of staurosporine was applied, a significantly increased proportion of early apoptotic cells was detected after regeneration in a staurosporine free medium. The proportion of necroptotic cells was already increased without regeneration after 3 hours of exposure to staurosporine. When a higher (10⁻⁶ M) concentration of staurosporine was applied, further significantly increased necroptosis was detected after regeneration in a staurosporine free medium. Necroptosis was significantly reduced when RIP1 kinase was inhibited by necrostatin-1, whereas inhibition of caspases with z-vad-fmk, an irreversible pan-caspase inhibitor, did not prevent necroptosis. This report of necroptosis induced by staurosporine represents a simple approach for the in vitro induction and detection of apoptosis and necroptosis.