Referenced in: none

Automatically associated channels: Nav1.6

Title: Analgesic effects of clinically used compounds in novel mouse models of polyneuropathy induced by oxaliplatin and cisplatin.

Authors: Jennifer R Deuis, Yu Ling Lim, Silmara Rodrigues de Sousa, Richard J Lewis, Paul F Alewood, Peter J Cabot, Irina Vetter

Journal, date & volume: Neuro-oncology, 2014 Oct , 16, 1324-32

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/24714523

Abstract
Peripheral neuropathy is the major dose-limiting side effect of cisplatin and oxaliplatin, and there are currently no effective treatments available. The aim of this study was to assess the pharmacological mechanisms underlying chemotherapy-induced neuropathy in novel animal models based on intraplantar administration of cisplatin and oxaliplatin and to systematically evaluate the analgesic efficacy of a range of therapeutics.Neuropathy was induced by a single intraplantar injection of cisplatin or oxaliplatin in C57BL/6J mice and assessed by quantification of mechanical and thermal allodynia. The pharmacological basis of cisplatin-induced neuropathy was characterized using a range of selective pharmacological inhibitors. The analgesic effects of phenytoin, amitriptyline, oxcarbazepine, mexiletine, topiramate, retigabine, gabapentin, fentanyl, and Ca(2+/)Mg(2+) were assessed 24 hours after induction of neuropathy.Intraplantar administration of cisplatin led to the development of mechanical allodynia, mediated through Nav1.6-expressing sensory neurons. Unlike intraplantar injection of oxaliplatin, cold allodynia was not observed with cisplatin, consistent with clinical observations. Surprisingly, only fentanyl was effective at alleviating cisplatin-induced mechanical allodynia despite a lack of efficacy in oxaliplatin-induced cold allodynia. Conversely, lamotrigine, phenytoin, retigabine, and gabapentin were effective at reversing oxaliplatin-induced cold allodynia but had no effect on cisplatin-induced mechanical allodynia. Oxcarbazepine, amitriptyline, mexiletine, and topiramate lacked efficacy in both models of acute chemotherapy-induced neuropathy.This study established a novel animal model of cisplatin-induced mechanical allodynia consistent with the A-fiber neuropathy seen clinically. Systematic assessment of a range of therapeutics identified several candidates that warrant further clinical investigation.