MicroRNAs: The Tiny Robust Players Unraveling the Multifaceted Channels of Pain

Pain is a debilitating condition which is the leading cause of cognitive, mood and anxiety disorders. It is one of the major medical burdens on human health which obstructs the quality life of a person as the appropriate therapeutic solution is not available. Due to advancement of new genomic technologies, it is now possible to view genome wide changes during chronic pain in different cell types from the somatosensory system to the neurons in central nervous system. Tremendous research over recent years has enlightened the magical potential of small non-coding RNAs, mainly microRNAs in modulating numerous pathophysiological processes including proliferation, apoptosis and oncogenesis. They target a wide range of molecules and refine their protein output and thus, fine tune distinct cellular processes including pain signaling. Recently, animal models depicting inflammatory and neuropathic pain and patient subjects complaining distress due to pain have shown deregulations of miRNAs in affected tissues and systemic circulation. Although various painful conditions viz. spinal cord injury, peripheral nerve injury, cancer and inflammatory diseases have been recognized with genome-wide changes in microRNA signatures, yet the gene regulatory networks underlying pathological significance of individual microRNAs are sparsely studied. Hence, this chapter summarizes the latest findings addressing the role of microRNAs in various inflammatory or neuropathic pain conditions. How can miRNA research be expedited in revealing new aspects of pain pathophysiology is also addressed. The chapter also uncovers the novel potentials of miRNAs as well as roadblocks in the path of miRNA based anti-nociceptive therapies.

Keywords: DRG, miRNA, Nociceptive pathway, Pain, Spinal cord, TG.