Suppression of SCN9A gene expression and/or function for the treatment of pain
Disclosed herein are methods, sequences and nucleic acid molecules used to treat pain. Specifically, the methods and sequences include locally administering molecules that suppress the expression of amino acid sequences that encode for Na v 1.7 channels or that otherwise inhibit the function of Na v 1.7 channels. Local suppression of Na v 1.7 channel levels and/or function will occur in the peripheral sensory neurons of the dorsal root ganglia.
1. A method of treating pain comprising:
administering to a mammal in pain a pharmaceutical composition comprising at least one isolated nucleic acid molecule of about 19 to about 25 contiguous nucleotides comprising a sequence set forth in SEQ ID NO. 55 that is complementary to or identical to a target sequence of about 19 to about 25 contiguous nucleotides in SCN9A mRNA wherein said isolated nucleic acid molecule is a siRNA molecule;
introducing the siRNA molecule into a cell body of a dorsal root ganglion; and
suppressing the expression and/or function of Na v 1.7 channels in the dorsal root ganglion.
2. A method according to claim 1 wherein said isolated nucleic acid molecule is administered through a catheter and drug pump, via a controlled release polymer formulation or both.
3. A method according to claim 1 wherein said isolated nucleic acid molecule is in shRNA format and is delivered via a viral vector or a non-viral vector.
4. The method according to claim 1 wherein said isolated nucleic acid comprises a sense RNA strand and an antisense RNA strand, wherein said antisense RNA strand is complementary to said target sequence and said sense RNA strand is greater than 80% identical to said target sequence.
5. The method according to claim 4 wherein said sense and said antisense RNA strands are covalently linked by a single-stranded hairpin.