Evaluation of Molecular and Cellular Alterations Induced by Neuropathic Pain in Rat Brain Glial cells

Neuropathic pain originates from illness or damage of the nervous system and affects the somatosensory system. Recently, many efforts have been made to illuminate the influences of neuropathic pain in different parts of central nervous system (CNS). However, the toxic consequences of neuropathic pain in glial cells, which involve in the control of pain is poorly understood. Therefore, the present study aimed to assess the molecular and cellular effects of neuropathic pain in the glial cells of rat brain. Induction of neuropathic pain in rats was associated with oxidative stress as evident by elevated reactive oxygen species (ROS) formation as well as reversible glutathione (GSH) depletion in the glial cells. Moreover, neuropathic pain caused mitochondrial membrane potential collapse (∆Ψm%), lysosomal membrane rapture, and proteolysis, probably due to ROS-induced MPT pore opening. These toxic events could cause cytochrome c release from intermembrane space into the cytosole and trigger caspase activation pathway. Our finding confirmed that the activity of caspase-3 was significantly increased in the glial cells as a core component of the apoptotic machinery. In conclusion, the neuropathic pain induces ROS generation as the major cause of GSH depletion along with mutual mitochondrial/lysosomal potentiation (cross-talk) of oxidative stress in the glial cells. Subsequently, this toxic cross-talk can induce proteolysis and trigger apoptosis by caspase-3 activation in the glial cells of rat brain.