Dipartimento di Medicina Sperimentale, Università Sapienza Roma, 00161 Rome, Italy.
Centro di Biomedicina e Tecnologie Avanzate, Sabina Universitas Rieti, 02100 Rieti, Italy.
Molecules. 2021 Dec 23;27(1):64. doi: 10.3390/molecules27010064.
The endocannabinoid system (ECS) exerts immunosuppressive effects, which are mostly mediated by cannabinoid receptor 2 (CBR2), whose expression on leukocytes is higher than CBR1, mainly localized in the brain. Targeted CBR2 activation could limit inflammation, avoiding CBR1-related psychoactive effects. Herein, we evaluated in vitro the biological activity of a novel, selective and high-affinity CBR2 agonist, called JT11, studying its potential CBR2-mediated anti-inflammatory effect. Trypan Blue and MTT assays were used to test the cytotoxic and anti-proliferative effect of JT11 in Jurkat cells. Its pro-apoptotic activity was investigated analyzing both cell cycle and poly PARP cleavage. Finally, we evaluated its impact on LPS-induced ERK1/2 and NF-kB-p65 activation, TNF-α, IL-1β, IL-6 and IL-8 release in peripheral blood mononuclear cells (PBMCs) from healthy donors. Selective CB2R antagonist SR144528 and CBR2 knockdown were used to further verify the selectivity of JT11. We confirmed selective CBR2 activation by JT11. JT11 regulated cell viability and proliferation through a CBR2-dependent mechanism in Jurkat cells, exhibiting a mild pro-apoptotic activity. Finally, it reduced LPS-induced ERK1/2 and NF-kB-p65 phosphorylation and pro-inflammatory cytokines release in human PBMCs, proving to possess in vitro anti-inflammatory properties. JT11 as CBR2 ligands could enhance ECS immunoregulatory activity and our results support the view that therapeutic strategies targeting CBR2 signaling could be promising for the treatment of chronic inflammatory diseases.
内源性大麻素系统（ECS）发挥免疫抑制作用，主要由大麻素受体 2（CBR2）介导，其在白细胞上的表达高于 CBR1，主要定位于大脑。靶向 CBR2 激活可以限制炎症，避免与 CBR1 相关的精神活性作用。在此，我们评估了一种新型、选择性和高亲和力的 CBR2 激动剂 JT11 的体外生物学活性，研究其潜在的 CBR2 介导的抗炎作用。使用台盼蓝和 MTT 测定法在 Jurkat 细胞中测试 JT11 的细胞毒性和抗增殖作用。通过分析细胞周期和多聚 PARP 切割来研究其促凋亡活性。最后，我们评估了其对 LPS 诱导的外周血单个核细胞（PBMCs）中 ERK1/2 和 NF-kB-p65 激活、TNF-α、IL-1β、IL-6 和 IL-8 释放的影响来自健康供体。选择性 CB2R 拮抗剂 SR144528 和 CBR2 敲低用于进一步验证 JT11 的选择性。我们通过 JT11 证实了选择性 CBR2 激活。JT11 通过 CBR2 依赖性机制调节 Jurkat 细胞中的细胞活力和增殖，表现出轻微的促凋亡活性。最后，它降低了 LPS 诱导的 ERK1/2 和 NF-kB-p65 磷酸化和人 PBMCs 中促炎细胞因子的释放，证明具有体外抗炎特性。JT11 作为 CBR2 配体可以增强 ECS 免疫调节活性，我们的结果支持这样一种观点，即针对 CBR2 信号的治疗策略可能是治疗慢性炎症性疾病的有希望的方法。
