Rabbit Anti-Human OPRL1 (a.a. 1-47) Polyclonal antibody

Background Curcumin (CC) exerts polyvalent pharmacological actions and multi-target effects, including pain relief and anti-nociceptive activity. In combination with Boswellia serrata extract (BS), curcumin shows greater efficacy in knee osteoarthritis management, presumably due to synergistic interaction of the ingredients. Aim: To elucidate the molecular mechanisms underlying the analgesic activity of curcumin and its synergistic interaction with BS. Methods: We performed gene expression profiling by transcriptome-wide mRNA sequencing in human T98G neuroglia cells treated with CC (Curamed), BS, and the combination of CC and BS (CC-BS; Curamin), followed by interactive pathways analysis of the regulated genes. Results: Treatment with CC and with CC-BS selectively downregulated opioid-related nociceptin receptor 1 gene (OPRL1) expression by 5.9-fold and 7.2-fold, respectively. No changes were detected in the other canonical opioid receptor genes: OPRK1, OPRD1, and OPRM1. Nociceptin reportedly increases the sensation of pain in supra-spinal pain transduction pathways. Thus, CC and CC-BS may downregulate OPRL1, consequently inhibiting production of the nociception receptor NOP, leading to pain relief. In neuroglia cells, CC and CC-BS inhibited signaling pathways related to opioids, neuropathic pain, neuroinflammation, osteoarthritis, and rheumatoid diseases. CC and CC-BS also downregulated ADAM metallopeptidase gene ADAMTS5 expression by 11.2-fold and 13.5-fold, respectively. ADAMTS5 encodes a peptidase that plays a crucial role in osteoarthritis development via inhibition of a corresponding signaling pathway. Conclusion: Here, we report for the first time that CC and CC-BS act as nociceptin receptor antagonists, selectively downregulating opioid-related nociceptin receptor 1 gene (OPRL1) expression, which is associated with pain relief. BS alone did not affect OPRL1 expression, but rather appears to potentiate the effects of CC via multiple mechanisms, including synergistic interactions of molecular networks.

The amygdala-dependent molecular mechanisms driving the onset and persistence of posttraumatic stress disorder (PTSD) are poorly understood. Recent observational studies have suggested that opioid analgesia in the aftermath of trauma may decrease the development of PTSD. Using a mouse model of dysregulated fear, we found altered expression within the amygdala of the Oprl1 gene (opioid receptor-like 1), which encodes the amygdala nociceptin (NOP)/orphanin FQ receptor (NOP-R). Systemic and central amygdala infusion of SR-8993, a new highly selective NOP-R agonist, impaired fear memory consolidation. In humans, a single-nucleotide polymorphism (SNP) within OPRL1 is associated with a self-reported history of childhood trauma and PTSD symptoms (n = 1847) after a traumatic event. This SNP is also associated with physiological startle measures of fear discrimination and magnetic resonance imaging analysis of amygdala-insula functional connectivity. Together, these data suggest that Oprl1 is associated with amygdala function, fear processing, and PTSD symptoms. Further, our data suggest that activation of the Oprl1/NOP receptor may interfere with fear memory consolidation, with implications for prevention of PTSD after a traumatic event.