Mangione Antonina S, Obara Ilona, Maiarú Maria, Geranton Sandrine M, Tassorelli Cristina, Ferrari Enrico, Leese Charlotte, Davletov Bazbek, Hunt Stephen P
Cell and Developmental Biology, University College London, London, United Kingdom Laboratory of Neurophysiology of Integrative Autonomic System, Headache Sci. Ctr., "C. Mondino" Natl. Neurological Inst, Pavia, Italy School of Medicine, Pharmacy and Health., Durham Univ., Stockton-on-Tees, United Kingdom Department of Brain and Behavior, University of Pavia, Pavia, Italy School of Life Science, University of Lincoln, Lincoln, United Kingdom Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom.
Pain. 2016 May;157(5):1045-1055. doi: 10.1097/j.pain.0000000000000478.
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.
据报道,局部注射肉毒杆菌毒素不仅可用于治疗周围神经性疼痛和偏头痛,还会导致持久的肌肉麻痹,这是一种潜在的严重副作用。最近,已合成了一种基于A型肉毒杆菌的分子(“BiTox”),它保留了神经元沉默能力而不会引发肌肉麻痹。在本研究中,我们检查了外周给予的BiTox是否能够减轻或预防在炎症性疼痛、手术疼痛和神经性疼痛动物模型中发现的伤害性敏感性增加。还测量了血浆外渗、水肿以及角质形成细胞增殖。未观察到运动功能缺陷,BiTox注射也未损害急性热痛觉和机械痛觉阈值。我们发现局部注射BiTox后,皮肤组织中的血浆外渗和炎性水肿减少,角质形成细胞增殖水平降低。然而,我们没有发现证据表明BiTox被转运到背根神经节或背角,并且在福尔马林诱发的行为或辣椒素或福尔马林诱导的背角c-Fos表达方面没有缺陷。相比之下,BiTox治疗强烈降低了与完全弗氏佐剂(CFA)诱导的关节炎症或辣椒素注射相关的A伤害感受器介导的继发性机械性痛觉过敏以及与 spared nerve injury相关的超敏反应。这些结果表明,虽然BiTox注射抑制了C纤维中神经调节剂的局部释放,但C伤害性信号传导功能并未受损。结合最近的临床数据来看结果表明,对于认为A伤害感受器起重要作用疼痛病症应考虑使用BiTox进行治疗。