Long-Term Reduction of Kappa Opioid Receptor Function by the Biased Ligand, Norbinaltorphimine, Requires c-Jun N-Terminal Kinase Activity and New Protein Synthesis in Peripheral Sensory Neurons

Abstract

A single administration of the k opioid receptor (KOR) antagonist, norbinaltorphimine (norBNI), produces long-term reduction in KOR function in heterologous expression systems and brain that is mediated by activation of c-Jun N-terminal kinase (JNK). In this study, we examined the long-term effects of norBNI on adult rat peripheral sensory neurons in vivo and ex vivo. Following a single intraplantar (i.pl.) injection of norBNI into the hind paw, peripheral KOR-mediated antinociception in the ipsilateral, but not the contralateral, hindpaw was abolished for at least 9 days. By contrast, the antinociceptive response to mu and delta opioid receptor agonists was unaltered. The long-term inhibitory effect on antinociception produced by pretreatment with norBNI required occupancy of peripheral KOR and was completely blocked by i.pl. injection of the JNK inhibitor, SP600125. In cultures of peripheral sensory neurons, norBNI activated JNK for at least 30 minutes. Furthermore, norBNI blocked KORmediated inhibition of adenylyl cyclase activity measured 24 hours later in a JNK-dependent manner, but did not block activation of extracellular signal-regulated kinase (ERK). The long-term inhibitory effect of norBNI on KOR function in vivo and ex vivo was blocked by inhibitors of mRNA translation, cycloheximide and rapamycin. These data suggest that in peripheral sensory neurons norBNI is a KOR-biased ligand for activation of JNK signaling, resulting in long-term blockade of some (antinociception, inhibition of adenylyl cyclase activity), but not all (ERK), KOR signaling. Importantly, norBNI elicits de novo protein synthesis in sensory neuron terminals that produces selective long-term regulation of KOR.

Withdrawal-induced escalated oxycodone self-administration is mediated by kappa opioid receptor function

“…Thus, extended access oxycodone administration may selectively dysregulate this ligand-specific KOR-JNK pathway resulting in the specific switch seen with acute norBNI application, while leaving dynorphin/KOR agonist signaling intact. This norBNI-JNK pathway is not well understood (41,43), thus further investigation into the involvement of dysregulated JNK signaling is warranted.…”

Lateralized kappa opioid receptor signaling from the amygdala central nucleus promotes stress-induced functional pain

“…All nor-BNI or vehicle injections were given 1 hour prior to each environmental bright light stress session and the experimenter was blinded to the assigned treatment group. Although nor-BNI administration has been shown to cause long-term KOR inactivation [9,24,30,32,37] that exceeds the 24 hour period between stress sessions we gave one dose one hour prior to each environmental bright light stress to ensure that KORs were maximally blocked before each stress session.…”

Biased Receptor Signaling in Drug Discovery

“…Elegant studies with a range of biased PTH analogs have been valuable in elucidating the complicating bone-building and bone resorption effects of PTH for therapy of osteoporosis (Luttrell et al, 2018). The study of the biased k-opioid receptor antagonist norbinaltorphimine has enabled linkage of JNK signaling to long-term blockade of antinociception (with no ERK activity) and selective long-term effects on regulation of k-opioid receptors (Jamshidi et al, 2016). A novel application of bias in the delineation of the role of b-arrestin signaling in cardiac b-adrenoceptor function has been suggested in the use of a biased pepducin, (ICL)-1-9 [TAIAKFERLLQTVTNYFIT], to decouple b-arrestin signaling from occupation of the receptor (Carr et al, 2016).…”