Cannabinoid (CB) receptor agonists show robust antinociceptive effects in various pain models. However, most of the clinically potent CB1 receptor-active drugs derived from cannabis are considered concerning due to psychotomimetic side effects. Selective CB receptor ligands that do not induce CNS side effects are of clinical interest. The venoms of marine snail Conus are a natural source of various potent analgesic peptides, some of which are already FDA approved. In this study we evaluated the ability of several Conus venom extracts to interact with CB1 receptor. HEK293 cells expressing CB1 receptors were treated with venom extracts and CB1 receptor internalization was analyzed by immunofluorescence. Results showed C. textile (C. Tex) and C. miles (C. Mil) samples as the most potent. These were serially subfractionated by HPLC for subsequent analysis by internalization assays and for analgesic potency evaluated in the formalin test and after peripheral nerve injury. Intrathecal injection of C. Tex and C. Mil subfractions reduced flinching/licking behavior during the second phase of formalin test and attenuated thermal and mechanical allodynia in nerve injury model. Treatment with proteolytic enzymes reduced CB1 internalization of subfractions, indicating the peptidergic nature of CB1 active component. Further HPLC purification revealed two potent antinociceptive subfractions within C. Tex with CB1 and possible CB2 activity, with mild to no side effects in the CB tetrad assessment. CB conopeptides can be isolated from these active Conus venom-derived samples and further developed as novel analgesic agents for the treatment of chronic pain using cell based or gene therapy approaches.

大麻素 (CB) 受体激动剂在各种疼痛模型中显示出强大的镇痛作用。然而，由于拟精神病的副作用，大多数来自大麻的临床有效的 CB1 受体活性药物被认为是令人担忧的。不诱导 CNS 副作用的选择性 CB 受体配体具有临床意义。海螺Conus的毒液是各种强效镇痛肽的天然来源，其中一些已获得 FDA 批准。在这项研究中，我们评估了几种芋头毒液提取物与 CB1 受体相互作用的能力。用毒液提取物处理表达 CB1 受体的 HEK293 细胞，并通过免疫荧光分析 CB1 受体的内化。结果显示C. 纺织 (C. Tex)和C. 英里( C. Mil ) 样品为最有效的。这些通过 HPLC 连续细分，用于随后的内化分析分析和在福尔马林试验中和周围神经损伤后评估的镇痛效力。在福尔马林测试的第二阶段，鞘内注射C. Tex和C. Mil亚组分减少了畏缩/舔舐行为，并减轻了神经损伤模型中的热和机械异常性疼痛。用蛋白水解酶处理减少了亚组分的 CB1 内化，表明 CB1 活性成分的肽能性质。进一步的 HPLC 纯化揭示了C. Tex 中两种有效的镇痛亚组分具有 CB1 和可能的 CB2 活性，在 CB 四分体评估中具有轻度或无副作用。CB conopeptides 可以从这些活性芋螺毒液衍生样品中分离出来，并进一步开发为新型镇痛剂，用于使用基于细胞或基因治疗方法治疗慢性疼痛。