Global gene profiling of rotenone-induced neuronal death

Rotenone is a naturally occurring toxic substance from the Leguminosa plant and belongs to the group of compounds known as rotenoids (Bové et al., 2005). It is commercially used as a pesticide and is epidemiologically linked to PD. Being lipophilic, rotenone can diffuse across biological membranes in the body and gain entry to all the organs and cells (Bové et al., 2005). Rotenone can bind to complex I of the electron transport chain (ETC) and inhibit the enzymatic activity of the NADH-ubiquinone reductase (Schuler and Casida, 2001). This interferes with the oxidation phosphorylation process, and eventually causes cell damage via oxidative stress. Rotenone may also cause the depolymerisation of microtubules into tubulin monomers (Marshall and Himes, 1978). Accumulation of tubulin monomers is potentially cytotoxic, and it is believed that parkin reverses cytotoxicity by ubiquitinating these monomers and targeting them for proteasome degradation (Ren et al., 2003.). Unfortunately, in PD patients with parkin mutations, this is not possible and tubulin accumulates to harmful levels in the cells. A total of 13 RNA samples were analyzed. Cultured murine primary cortical neurons were treated with 10nM rotenone over a time-course of 8h, 15h and 24h (n=3) in addition to the vehicle control (n=4).