Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2004 Mar 16;32(5):e49.
doi: 10.1093/nar/gnh044.

siRNA relieves chronic neuropathic pain

Gabriele Dorn  1 , Sadhana Patel, Glen Wotherspoon, Maja Hemmings-Mieszczak, Jane Barclay, Francois J C Natt, Pierre Martin, Stuart Bevan, Alyson Fox, Pam Ganju, William Wishart, Jonathan Hall
Affiliations

siRNA relieves chronic neuropathic pain

Gabriele Dorn et al. Nucleic Acids Res. .

Abstract

Double stranded, short interfering RNAs (siRNA) of 21-22 nt length initiate a sequence-specific, post-trancriptional gene silencing in animals and plants known as RNA interference (RNAi). Here we show that RNAi can block a pathophysiological pain response and provide relief from neuropathic pain in a rat disease model by down regulating an endogenous, neuronally expressed gene. Rats, intrathecally infused with a 21 nt siRNA perfectly complementary to the pain-related cation-channel P2X3, showed diminished pain responses compared to missense (MS) siRNA-treated and untreated controls in models of both agonist-evoked pain and chronic neuropathic pain. This form of delivery caused no adverse effects in any of the animals receiving P2X3 siRNA, MS siRNA or vehicle. Molecular analysis of tissues revealed that P2X3 mRNA expressed in dorsal root ganglia, and P2X3 protein translocated into the dorsal horn of the spinal cord, were significantly diminished. These observations open a path toward use of siRNA as a genetic tool for drug target validation in the mammalian central nervous system, as well as for proof of concept studies and as therapeutic agents in man.

PubMed Disclaimer

Figures

Figure 1
Figure 1
P2X3 siRNA reduced agonist-induced pain in vivo. Significant inhibition of α,β-methylene-ATP evoked (A) mechanical hyperalgesia and (B) tactile allodynia in the hind paw of naïve rats after 6-day intrathecal treatment with P2X3 siRNA compared to MS siRNA or vehicle. PWTs were measured prior to cannulation on day 0, and on day 6 before and after intraplantar injection of 1 µmol α,β-methylene-ATP (n/group = 6).
Figure 2
Figure 2
Molecular down regulation of P2X3 RNA and protein upon treatment with siRNA. (A) P2X3 mRNA levels in lumbar L4/L5 DRG, normalized to β-actin, were significantly reduced in P2X3 siRNA- versus MS siRNA- and vehicle-treated rats (n/group = 3). (B) P2X3 immunoreactivity in lamina II of the spinal cord was visibly reduced in siRNA-treated animals (top panel). Co-immunostaining with neuron-specific isolectin B4 (green) showed that equivalent regions of each spinal cord were analysed (n/group = 3).
Figure 3
Figure 3
P2X3 siRNA reduced tactile allodynia in a neuropathic pain model. (A) Tactile allodynia was significantly inhibited in the neuropathic paw (partially ligated sciatic nerve) in P2X3 siRNA- versus MS siRNA-, P2X3 ASO- and vehicle-treated rats. An additional naïve (non-ligated) group that received vehicle only controlled for the cannulation process. (B) PWTs in the contralateral paws of all groups were the same as naïve animals. Upon agonist injection (1 µmol α,β-methylene-ATP) on the last day of the experiment (day 17), all control groups and the ASO group showed agonist-induced tactile allodynia when assayed at 15, 30 and 60 min post injection. P2X3 siRNA significantly diminished agonist-induced tactile allodynia (n/group = 8).
Figure 4
Figure 4
P2X3 siRNA reduced mechanical hyperalgesia in a neuropathic pain model. (A) Mechanical hyperalgesia was significantly inhibited in the neuropathic paw (partially ligated sciatic nerve) in P2X3 siRNA- and in P2X3 ASO- versus MS siRNA- and vehicle-treated rats. As a control, an additional naïve vehicle group had not been ligated and showed normal pain perception. (B) PWTs in the contralateral paws of all groups was the same as normal animals. Upon agonist injection (1 µmol α,β-methylene-ATP) on the last day of the experiment (day 17), all groups showed agonist-induced mechanical hyperalgesia at 15 min after injection, except for the P2X3 siRNA- and the ASO-treated groups. P2X3 siRNA completely suppressed agonist-induced mechanical hyperalgesia (n/group = 8).
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Sharp P.A. (2001) RNA interference–2001. Genes Dev., 15, 485–490. - PubMed
    1. Tuschl T. (2001) RNA interference and small interfering RNAs. ChemBioChem, 2, 239–245. - PubMed
    1. Hammond S.M., Caudy,A.A. and Hannon,G.J. (2001) Post-transcriptional gene silencing by double-stranded RNA. Nat. Rev. Genet., 2, 110–119. - PubMed
    1. Waterhouse P.M., Wang,M.B. and Lough,T. (2001) Gene silencing as an adaptive defence against viruses. Nature, 411, 834–842. - PubMed
    1. Elbashir S.M., Harborth,J., Lendeckel,W., Yalcin,A., Weber,K. and Tuschl,T. (2001) Duplexes of 21-nucleotide RNAs mediate RNA interference in cultured mammalian cells. Nature, 411, 494–498. - PubMed

Substances