Objectives: To explore the effects of cannabidiol on endoplasmic reticulum stress and neuronal apoptosis in rats with multiple concussions (MCC).
Methods: SD rats were randomized into sham group, MCC group, 1% tween20 (TW) treatment group, and low-dose (10 mg/kg) and high-dose (40 mg/kg) cannabidiol treatment groups. In all but the sham group, MCC models were established using a metal pendulum percussion device, after which the rats received daily intraperitoneal injections of the corresponding agents for 2 weeks. The expressions of PERK, eIF2α, ATF4, CHOP, TRIB3, p-Akt and pro-caspase-3 in the brain tissue of the rats were detected with qRT-PCR, Western blotting and immunofluorescence staining. The core targets of cannabidiol in treatment of traumatic brain injury (TBI) were identified by network pharmacology analysis, and molecular docking was carried out to simulate the interaction of cannabidiol with the factors related to endoplasmic reticulum stress and apoptosis.
Results: Compared with the sham-operated rats, the rat models of MCC showed significantly increased mRNA expressions of PERK, eIF2α and CHOP and protein expressions of PERK, eIF2α, ATF4, CHOP, TRIB3, p-AKT and pro-caspase-3 in the cerebral cortex. CBD treatment, especially at the high dose, obviously increased the expression of p-Akt and lowered the expression levels of the other factors tested in the rat models. Network pharmacology analysis indicated interactions of the core targets of CBD with the factors related to endoplasmic reticulum stress and TBI, and molecular docking study showed a high binding energy of CBD with multiple factors pertaining to endoplasmic reticulum stress and apoptosis.
Conclusions: MCC induce endoplasmic reticulum stress and apoptosis in rat brain tissues, for which CBD, especially at a high dose, provides neuroprotective effects by inhibiting endoplasmic reticulum stress and cell apoptosis.
目的: 探究大麻二酚（CBD）对多重脑震荡后神经元内质网应激及其介导的神经元凋亡的作用。方法: 将SD大鼠分为假手术组（sham组）、多重脑震荡组（MCC组）、多重脑震荡溶剂组（MCC+TW组，1% tween20）、低剂量CBD-10组（10 mg/kg）和高剂量CBD-40组（40 mg/kg），用金属单摆打击装置制成大鼠MCC模型，给药各组于造模成功后连续腹腔给药2周。采用qRT-PCR、Western blotting和免疫荧光染色检测大鼠脑组织中PERK、eIF2α、ATF4、CHOP、TRIB3、p-AKT、Pro-caspase-3的表达变化。通过网络药理学筛选CBD治疗创伤性脑损伤的核心靶点，经Autodock可视化分析CBD与内质网应激和凋亡相关因子的分子对接情况。结果: MCC后大脑皮质内质网应激因子PERK、eIF2α、CHOP mRNA表达水平升高（P<0.05）。MCC组大脑皮质中PERK、eIF2α、ATF4、CHOP、TRIB3、p-AKT、Pro-caspase-3蛋白表达水平较sham组升高（P<0.05）；CBD治疗后，p-AKT表达水平进一步升高（P<0.05），而其余因子表达水平均降低（P<0.05），且CBD-40组降低更显著。网络药理学分析显示，CBD治疗TBI的核心靶点与内质网应激和脑损伤因子存在蛋白互作关系；分子对接显示CBD，与多个内质网应激和凋亡因子具有较高的结合能。结论: 大鼠多重脑震荡诱发神经元内质网应激和细胞凋亡，CBD可通过抑制内质网应激和抗凋亡发挥神经保护作用，且高剂量CBD的保护作用更明显。.
Keywords: PERK signaling pathway; cannabidiol; endoplasmic reticulum stress; multiple cerebral concussions; neuronal apoptosis.