Reactive oxygen species (ROS) generation is stimulated by κ opioid receptor activation through phosphorylated c-Jun N-terminal kinase and inhibited by p38 mitogen-activated protein kinase (MAPK) activation.

Autor: Schattauer SS; Department of Pharmacology, University of Washington School of Medicine, Seattle, Washington 98195., Bedini A; Department of Pharmacy and Biotechnology (FaBiT), University of Bologna, Irnerio, 48-40126 Bologna, Italy., Summers F; Department of Pharmacology, University of Washington School of Medicine, Seattle, Washington 98195., Reilly-Treat A; Department of Pharmacology, University of Washington School of Medicine, Seattle, Washington 98195., Andrews MM; Department of Pharmacology, University of Washington School of Medicine, Seattle, Washington 98195.; Department of Bioengineering, University of Washington College of Engineering, Seattle, Washington 98195., Land BB; Department of Pharmacology, University of Washington School of Medicine, Seattle, Washington 98195., Chavkin C; Department of Pharmacology, University of Washington School of Medicine, Seattle, Washington 98195 cchavkin@uw.edu.
Jazyk: angličtina
Zdroj: The Journal of biological chemistry [J Biol Chem] 2019 Nov 08; Vol. 294 (45), pp. 16884-16896. Date of Electronic Publication: 2019 Oct 01.
DOI: 10.1074/jbc.RA119.009592
Abstrakt: Activation of the mitogen-activated protein kinase (MAPK) c-Jun N-terminal kinase (JNK) by the G i/o protein-coupled κ opioid receptor (KOR), μ opioid, and D2 dopamine receptors stimulates peroxiredoxin 6 (PRDX6)-mediated production of reactive oxygen species (ROS). ROS production by KOR-inactivating antagonists norbinaltorphimine (norBNI) and JDTic blocks Gα i protein activation, but the signaling mechanisms and consequences of JNK activation by KOR agonists remain uncharacterized. Binding of arrestins to KOR causes desensitization of G protein signaling and acts as a scaffold to initiate MAPK activation. Here, we found that the KOR agonists U50,488 and dynorphin B stimulated biphasic JNK activation with an early arrestin-independent phase, requiring the small G protein RAC family small GTPase 1 (RAC1) and protein kinase C (PKC), and a later arrestin-scaffolded phase, requiring RAC1 and Ras homolog family member (RHO) kinase. JNK activation by U50,488 and dynorphin B also stimulated PRDX6-dependent ROS production but with an inverted U-shaped dose-response relationship. KOR agonist-induced ROS generation resulted from the early arrestin-independent phase of JNK activation, and this ROS response was suppressed by arrestin-dependent activation of the MAPK p38. The apparent balance between p38 MAPK and JNK/ROS signaling has important physiological implications for understanding of dynorphin activities during the stress response. To visualize these activities, we monitored KOR agonist-mediated activation of ROS in transfected live cells by two fluorescent sensors, CellROX Green and HyPerRed. These findings establish an important aspect of opioid receptor signaling and suggest that ROS induction may be part of the physiological response to KOR activation.
(© 2019 Schattauer et al.)
Databáze: MEDLINE
Externí odkaz: