A high‐affinity, bivalent PDZ domain inhibitor complexes PICK1 to alleviate neuropathic pain

• Published in: EMBO molecular medicine Vol. 12; no. 6; pp. e11248 - n/a
• Main Authors: Christensen, Nikolaj R, De Luca, Marta, Lever, Michael B, Richner, Mette, Hansen, Astrid B, Noes‐Holt, Gith, Jensen, Kathrine L, Rathje, Mette, Jensen, Dennis Bo, Erlendsson, Simon, Bartling, Christian RO, Ammendrup‐Johnsen, Ina, Pedersen, Sofie E, Schönauer, Michèle, Nissen, Klaus B, Midtgaard, Søren R, Teilum, Kaare, Arleth, Lise, Sørensen, Andreas T, Bach, Anders, Strømgaard, Kristian, Meehan, Claire F, Vægter, Christian B, Gether, Ulrik, Madsen, Kenneth L
• Format: Journal Article
• Language: English
• Published: England John Wiley and Sons Inc 08.06.2020; Springer Nature
• Subjects: biopharmaceuticals; calcium permeable AMPARs; Carrier Proteins - metabolism; Humans; maladaptive plasticity; Neuralgia - drug therapy; Nuclear Proteins - metabolism; PDZ Domains; Receptors, AMPA - metabolism; scaffold proteins; synaptic plasticity; biopharmaceuticals; scaffold proteins; maladaptive plasticity; synaptic plasticity; calcium permeable AMPARs
• ISSN: 1757-4676; 1757-4684
• DOI: 10.15252/emmm.201911248

Maladaptive plasticity involving increased expression of AMPA‐type glutamate receptors is involved in several pathologies, including neuropathic pain, but direct inhibition of AMPARs is associated with side effects. As an alternative, we developed a cell‐permeable, high‐affinity (~2 nM) peptide inhibitor, Tat‐P4‐(C5)2, of the PDZ domain protein PICK1 to interfere with increased AMPAR expression. The affinity is obtained partly from the Tat peptide and partly from the bivalency of the PDZ motif, engaging PDZ domains from two separate PICK1 dimers to form a tetrameric complex. Bivalent Tat‐P4‐(C5)2 disrupts PICK1 interaction with membrane proteins on supported cell membrane sheets and reduce the interaction of AMPARs with PICK1 and AMPA‐receptor surface expression in vivo. Moreover, Tat‐P4‐(C5)2 administration reduces spinal cord transmission and alleviates mechanical hyperalgesia in the spared nerve injury model of neuropathic pain. Taken together, our data reveal Tat‐P4‐(C5)2 as a novel promising lead for neuropathic pain treatment and expand the therapeutic potential of bivalent inhibitors to non‐tandem protein–protein interaction domains. Synopsis Neuropathic pain is characterized by hypersensitivity to temperature and touch as well as spontaneous outburst of pain. This study identifies a peptide that can inhibit PICK1 and thereby interfere with insertion of excess glutamate receptor underlying the hypersensitivity in neuropathic pain. Tat‐P4‐(C5)2 is a selective, high‐affinity inhibitor of the PICK1 PDZ domain that effectively interfere with the interaction of the GluA2 subunit of the AMPA type glutamate receptors. The high affinity is achieved in a combination between the Tat peptide and a bivalent PDZ interacting sequence that bring PICK1 into a complex of dimers‐of‐dimers. Tat‐P4‐(C5)2 disrupt TNFalpha‐induced expression of calcium permeable AMPA receptors and transmission in both DRG neuron and layer 1 and 2 cells in the dorsal horn of the spinal cord. Tat‐P4‐(C5)2 increases the paw withdrawal threshold to normal in the SNI model of neuropathic pain after intrathecal but not intraplantar injection in accordance with a central mechanism of action. Neuropathic pain is characterized by hypersensitivity to temperature and touch as well as spontaneous outburst of pain. This study identifies a peptide that can inhibit PICK1 and thereby interfere with insertion of excess glutamate receptor underlying the hypersensitivity in neuropathic pain.