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Nonparalytic botulinum molecules for the control of pain.

Mangione AS, Obara I, Maiarú M, Geranton SM, Tassorelli C, Ferrari E, Leese C, Davletov B, Hunt SP - Pain (2016)

Bottom Line: In this study, we examined whether BiTox delivered peripherally was able to reduce or prevent the increased nociceptive sensitivity found in animal models of inflammatory, surgical, and neuropathic pain.In contrast, Bitox treatment strongly reduced A-nociceptor-mediated secondary mechanical hyperalgesia associated with either complete Freund's adjuvant (CFA)-induced joint inflammation or capsaicin injection and the hypersensitivity associated with spared nerve injury.Taken together with recent clinical data the results suggest that BiTox should be considered for treatment of pain conditions in which A-nociceptors are thought to play a significant role.

View Article: PubMed Central - PubMed

Affiliation: aCell and Developmental Biology, University College London, London, United KingdombLaboratory of Neurophysiology of Integrative Autonomic System, Headache Sci. Ctr., "C. Mondino" Natl. Neurological Inst, Pavia, ItalycSchool of Medicine, Pharmacy and Health., Durham Univ., Stockton-on-Tees, United KingdomdDepartment of Brain and Behavior, University of Pavia, Pavia, ItalyeSchool of Life Science, University of Lincoln, Lincoln, United KingdomfDepartment of Biomedical Science, University of Sheffield, Sheffield, United Kingdom.

ABSTRACT
Local injections of botulinum toxins have been reported to be useful not only for the treatment of peripheral neuropathic pain and migraine but also to cause long-lasting muscle paralysis, a potentially serious side effect. Recently, a botulinum A-based molecule ("BiTox") has been synthesized that retains neuronal silencing capacity without triggering muscle paralysis. In this study, we examined whether BiTox delivered peripherally was able to reduce or prevent the increased nociceptive sensitivity found in animal models of inflammatory, surgical, and neuropathic pain. Plasma extravasation and edema were also measured as well as keratinocyte proliferation. No motor deficits were seen and acute thermal and mechanical nociceptive thresholds were unimpaired by BiTox injections. We found reduced plasma extravasation and inflammatory edema as well as lower levels of keratinocyte proliferation in cutaneous tissue after local BiTox injection. However, we found no evidence that BiTox was transported to the dorsal root ganglia or dorsal horn and no deficits in formalin-elicited behaviors or capsaicin or formalin-induced c-Fos expression within the dorsal horn. In contrast, Bitox treatment strongly reduced A-nociceptor-mediated secondary mechanical hyperalgesia associated with either complete Freund's adjuvant (CFA)-induced joint inflammation or capsaicin injection and the hypersensitivity associated with spared nerve injury. These results imply that although local release of neuromodulators from C-fibers was inhibited by BiTox injection, C-nociceptive signaling function was not impaired. Taken together with recent clinical data the results suggest that BiTox should be considered for treatment of pain conditions in which A-nociceptors are thought to play a significant role.

No MeSH data available.


Related in: MedlinePlus

Absence of cleaved SNAP25 in the dorsal horn and DRG after IPLT injection of BiTox. Rats received IPLT injection of BiTox (200 ng) 3 days before sacrifice. The intensity of the bands for cSNAP25 antibody was normalized against the GADPH signal used as internal standard for protein loading in dorsal horn (A). (A and B) show no evidence of cSNAP25 in the DRG or spinal cord 3 days after ipsilateral IPLT BiTox injection. Data are presented as means ± SEM. P > 0.05. n = 6 animals per group.
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Figure 11: Absence of cleaved SNAP25 in the dorsal horn and DRG after IPLT injection of BiTox. Rats received IPLT injection of BiTox (200 ng) 3 days before sacrifice. The intensity of the bands for cSNAP25 antibody was normalized against the GADPH signal used as internal standard for protein loading in dorsal horn (A). (A and B) show no evidence of cSNAP25 in the DRG or spinal cord 3 days after ipsilateral IPLT BiTox injection. Data are presented as means ± SEM. P > 0.05. n = 6 animals per group.

Mentions: We investigate whether BiTox was axonally transported to the central nervous system. Dorsal horn and DRG tissue were removed 3 days after IPLT injections of BiTox. Highly sensitive Western blotting failed to demonstrate the presence of cleaved SNAP25 in the dorsal horn and DRG ipsilaterally to the BiTox injection (Fig. 11A and B). SiMa neuroblastoma cells cleaved with BiTox over 3 days were used as a positive control for cSNAP25. The cSNAP25 control, but not uncleaved SNAP25 (uncSNAP25), was clearly recognized by the cSNAP25 antibody. We also used the same antibody directed against cSNAP25 to stain dorsal horn tissue immunohistochemically. BiTox was injected IPLT and tissue for immunohistochemistry collected at 3, 5, 7, and 32 days later. We found no staining for cSNAP25 at any time point. As a positive control we used spinal cord sections from rats injected intrathecally with BiTox and survived 2 hours to 3 days without event. Extensive positive staining was seen in these spinal cords (data not shown).


Nonparalytic botulinum molecules for the control of pain.

Mangione AS, Obara I, Maiarú M, Geranton SM, Tassorelli C, Ferrari E, Leese C, Davletov B, Hunt SP - Pain (2016)

Absence of cleaved SNAP25 in the dorsal horn and DRG after IPLT injection of BiTox. Rats received IPLT injection of BiTox (200 ng) 3 days before sacrifice. The intensity of the bands for cSNAP25 antibody was normalized against the GADPH signal used as internal standard for protein loading in dorsal horn (A). (A and B) show no evidence of cSNAP25 in the DRG or spinal cord 3 days after ipsilateral IPLT BiTox injection. Data are presented as means ± SEM. P > 0.05. n = 6 animals per group.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4834813&req=5

Figure 11: Absence of cleaved SNAP25 in the dorsal horn and DRG after IPLT injection of BiTox. Rats received IPLT injection of BiTox (200 ng) 3 days before sacrifice. The intensity of the bands for cSNAP25 antibody was normalized against the GADPH signal used as internal standard for protein loading in dorsal horn (A). (A and B) show no evidence of cSNAP25 in the DRG or spinal cord 3 days after ipsilateral IPLT BiTox injection. Data are presented as means ± SEM. P > 0.05. n = 6 animals per group.
Mentions: We investigate whether BiTox was axonally transported to the central nervous system. Dorsal horn and DRG tissue were removed 3 days after IPLT injections of BiTox. Highly sensitive Western blotting failed to demonstrate the presence of cleaved SNAP25 in the dorsal horn and DRG ipsilaterally to the BiTox injection (Fig. 11A and B). SiMa neuroblastoma cells cleaved with BiTox over 3 days were used as a positive control for cSNAP25. The cSNAP25 control, but not uncleaved SNAP25 (uncSNAP25), was clearly recognized by the cSNAP25 antibody. We also used the same antibody directed against cSNAP25 to stain dorsal horn tissue immunohistochemically. BiTox was injected IPLT and tissue for immunohistochemistry collected at 3, 5, 7, and 32 days later. We found no staining for cSNAP25 at any time point. As a positive control we used spinal cord sections from rats injected intrathecally with BiTox and survived 2 hours to 3 days without event. Extensive positive staining was seen in these spinal cords (data not shown).

Bottom Line: In this study, we examined whether BiTox delivered peripherally was able to reduce or prevent the increased nociceptive sensitivity found in animal models of inflammatory, surgical, and neuropathic pain.In contrast, Bitox treatment strongly reduced A-nociceptor-mediated secondary mechanical hyperalgesia associated with either complete Freund's adjuvant (CFA)-induced joint inflammation or capsaicin injection and the hypersensitivity associated with spared nerve injury.Taken together with recent clinical data the results suggest that BiTox should be considered for treatment of pain conditions in which A-nociceptors are thought to play a significant role.

View Article: PubMed Central - PubMed

Affiliation: aCell and Developmental Biology, University College London, London, United KingdombLaboratory of Neurophysiology of Integrative Autonomic System, Headache Sci. Ctr., "C. Mondino" Natl. Neurological Inst, Pavia, ItalycSchool of Medicine, Pharmacy and Health., Durham Univ., Stockton-on-Tees, United KingdomdDepartment of Brain and Behavior, University of Pavia, Pavia, ItalyeSchool of Life Science, University of Lincoln, Lincoln, United KingdomfDepartment of Biomedical Science, University of Sheffield, Sheffield, United Kingdom.

ABSTRACT
Local injections of botulinum toxins have been reported to be useful not only for the treatment of peripheral neuropathic pain and migraine but also to cause long-lasting muscle paralysis, a potentially serious side effect. Recently, a botulinum A-based molecule ("BiTox") has been synthesized that retains neuronal silencing capacity without triggering muscle paralysis. In this study, we examined whether BiTox delivered peripherally was able to reduce or prevent the increased nociceptive sensitivity found in animal models of inflammatory, surgical, and neuropathic pain. Plasma extravasation and edema were also measured as well as keratinocyte proliferation. No motor deficits were seen and acute thermal and mechanical nociceptive thresholds were unimpaired by BiTox injections. We found reduced plasma extravasation and inflammatory edema as well as lower levels of keratinocyte proliferation in cutaneous tissue after local BiTox injection. However, we found no evidence that BiTox was transported to the dorsal root ganglia or dorsal horn and no deficits in formalin-elicited behaviors or capsaicin or formalin-induced c-Fos expression within the dorsal horn. In contrast, Bitox treatment strongly reduced A-nociceptor-mediated secondary mechanical hyperalgesia associated with either complete Freund's adjuvant (CFA)-induced joint inflammation or capsaicin injection and the hypersensitivity associated with spared nerve injury. These results imply that although local release of neuromodulators from C-fibers was inhibited by BiTox injection, C-nociceptive signaling function was not impaired. Taken together with recent clinical data the results suggest that BiTox should be considered for treatment of pain conditions in which A-nociceptors are thought to play a significant role.

No MeSH data available.


Related in: MedlinePlus