Role of Apolipoprotein E in the tangled mystery of pain.

Pain is one of the common and debilitating health manifestations associated with the majority of diseased conditions, thus making it a serious health concern worldwide. While trying to decipher the cryptic mechanism of pain in hope to provide better gene-based therapeutics, researchers have concluded pain to be of multigenic origin making it hard to cure. Apolipoprotein E is a protein coded by APOE gene containing 4 exons, located on chromosome 19q13.2. It is among the key regulators of various crucial body functions such as lipid transport, apoptosis, vitamin k pathway, and cognition, hence, it is highly suspected to play a pivotal role in the nociception process. However, very few studies have tried and succeeded to find a direct involvement of APOE in pain processing. The current article attempts to throw light on some of the major clinical research findings which strengthen the hypothesis stating that apolipoprotein E has a concealed yet deeply embedded association with the pain regulating pathways, through several underlying physiological, biochemical and neurological processes, that in turn, decide the fate of pain sensation in a complex manner.