P2RX7 and amyotrophic lateral sclerosis: Moreover, specific activation of P2X7 dysregulates inflammatory microRNA expression (Parisi et al., 2013), exacerbates NADPH oxidase 2 (NOX2; also known as gp91phox) activity, reactive oxygen species production, tumor necrosis factor α (TNF-α) and levels of COX-2 and MAPKs in ALS-microglia primary cultures, with consequent toxicity towards neuronal cells (Apolloni et al., 2013a; D’Ambrosi et al., 2009), as well as providing a neurotoxic function that is mediated by astrocytes (Gandelman et al., 2010).