Abstract
Chronic pain, whether of inflammatory or neuropathic origin, affects about 18% of the population of developed countries, and most current treatments are only moderately effective and/or cause serious side effects. Therefore, the development of novel therapeutic approaches still represents a major challenge. The Na,K-ATPase modulator FXYD2 is critically required for the maintenance of neuropathic pain in rodents. Here, we set up a therapeutic protocol based on the use of chemically modified antisense oligonucleotides (ASOs) to inhibit FXYD2 expression and treat chronic pain. We identified an ASO targeting a 20-nucleotide stretch in the FXYD2 mRNA that is evolutionarily conserved between rats and humans and is a potent inhibitor of FXYD2 expression. We used this sequence to synthesize lipid-modified forms of ASO (FXYD2-LASO) to facilitate their entry into dorsal root ganglia neurons. We established that intrathecal or intravenous injections of FXYD2-LASO in rat models of neuropathic or inflammatory pain led to a virtually complete alleviation of their pain symptoms, without causing obvious side effects. Remarkably, by using 2′-O-2-methoxyethyl chemical stabilization of the ASO (FXYD2-LASO-Gapmer), we could significantly prolong the therapeutic action of a single treatment up to 10 days. This study establishes FXYD2-LASO-Gapmer administration as a promising and efficient therapeutic strategy for long-lasting relief of chronic pain conditions in human patients.
Authors
Alexandre Derre, Noelian Soler, Valentine Billoux, Sebastien Benizri, Brune Vialet, Cyril Rivat, Philippe Barthélémy, Patrick Carroll, Alexandre Pattyn, Stephanie Venteo
Figure 3
FXYD2 inhibition by intrathecal injection of FXYD2-LASO or FXYD2-Accell siRNA reduces mechanical hypersensitivity in the neuropathic pain model (SNL); this treatment does not act by modulating the activity of the opioid receptor and is at least as effective as ω-conotoxin MVIIA for pain relief.
