Synthetic cannabinoid CP-55,940 induces apoptosis in a human skeletal muscle model via regulation of CB1 receptors and l-type Ca2+ channels
Synthetic cannabinoid CP-55,940 induces apoptosis in a human skeletal muscle model via regulation of CB1 receptors and l-type Ca2+ channels
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DOI：
10.1007/s00204-020-02944-7
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发表时间：
2020-11-10
影响因子：
6.1
通讯作者：
Funada，Masahiko
中科院分区：
文献类型：
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作者：
Tomiyama，Ken-ichi;Funada，Masahiko
据报道，滥用合成大麻素的患者出现横纹肌溶解症。然而，尚未有研究评估这些病例是否反映了合成大麻素对骨骼肌的直接细胞毒性，这是本研究试图解决的可能性。具体来说，这项研究调查了合成大麻素 CP-55,940 在人胚胎横纹肌肉瘤 (RD) 细胞系中的细胞毒性，该化合物对两种类型的大麻素受体（CB1 和 CB2）具有同等作用。这些细胞暴露于 CP-55,940 会导致细胞活力出现浓度依赖性下降。与选择性 CB1 受体拮抗剂 AM251 (30 µM) 预孵育可减弱这些效应，但与选择性 CB2 受体拮抗剂 AM630 (30 µM) 预孵育则不会减弱这些效应。用 CP-55,940 处理后，RD 细胞表现出细胞凋亡，如膜联蛋白-V 的积累、caspase-3 的激活和线粒体膜电位的丧失所示。此外，CP-55,940 处理 RD 细胞会导致细胞内 Ca2+ 水平增加。在没有细胞外 Ca2+ 的情况下，CP-55,940 诱导的细胞死亡显着减弱，并且通过用维拉帕米 (5 µM) 或地尔硫卓 (5 µM)（阻断 1 型 Ca2+ 通道的化合物）预孵育部分减少。我们的结果表明，CP-55,940 对 RD 细胞（骨骼肌细胞）的细胞毒性是由 CB1 受体介导的，而不是由 CB2 受体介导的。我们的结果进一步表明，通过I型通道的钙流入可能在这些化合物诱导的细胞凋亡中发挥重要作用。
Rhabdomyolysis has been reported in patients who abuse synthetic cannabinoids. However, no studies have yet assessed whether these cases reflect the direct cytotoxicity of synthetic cannabinoids on skeletal muscle, a possibility that the present study sought to address. Specifically, this study investigated the cytotoxicity of the synthetic cannabinoid CP-55,940, a compound that acts equally on both types of cannabinoid receptors (CB1and CB2), in a human embryonic rhabdomyosarcoma (RD) cell line. Exposure of these cells to CP-55,940 resulted in concentration-dependent decreases in cell viability. These effects were attenuated by pre-incubation with AM251 (30 µM), a selective CB1receptor antagonist, but not by pre-incubation with AM630 (30 µM), a selective CB2receptor antagonist. Following treatment with CP-55,940, RD cells exhibited apoptosis, as indicated by the accumulation of annexin-V, activation of caspase-3, and a loss of the mitochondrial membrane potential. Additionally, CP-55,940 treatment of RD cells led to increases in intracellular Ca2+levels. CP-55,940-induced cell death was significantly attenuated in the absence of extracellular Ca2+, and was partially decreased by pre-incubation with verapamil (5 µM) or diltiazem (5 µM), compounds that block thel-type Ca2+channel. Our results indicate that the cytotoxicity of CP-55,940 towards RD cells (skeletal muscle cells) is mediated by the CB1receptor, but not by the CB2receptor. Our results further suggest that calcium influx through thel-type channel may play an important role in the apoptosis induced by these compounds.