人参-玉竹药对抑制炎性小体NLRP1、NLRC4、AIM2活化及调控炎症因子表达的抗抑郁作用机制研究

Study on the antidepressant mechanism of ginseng-fragrant solomonseal rhizome couplet medicines on inhibiting the activation of inflammasomes NLRP1,NLRC4,and AIM2,and regulating the expression of inflammatory cytokines

目的 观察人参-玉竹药对对抑郁症大鼠炎性因子和炎性小体的影响,探讨人参-玉竹药对抗抑郁的作用机制。方法 50只雄性SD大鼠任意分为空白组、模型组、氟西汀组(2.1 mg/kg)、人参-玉竹低剂量组(1.89 g/kg)、人参-玉竹高剂量组(5.67 g/kg),每组10只。除空白组外,其他各组大鼠采用慢性不可预见性温和应激法建立抑郁症模型。造模结束后第2天,各组大鼠灌胃相应药物,每日1次,连续14 d。造模后、给药后检测大鼠体质量、强迫游泳不动时间、糖水偏好率;给药后,苏木素-伊红染色观察脑皮质神经元受损情况;酶联免疫吸附测定法检测脑皮质白细胞介素-4(IL-4)、白细胞介素-23(IL-23)、白细胞介素-27(IL-27)含量;实时荧光PCR法检测脑皮质白细胞介素-24(IL-24)mRNA表达;蛋白质印迹法检测脑皮质核苷酸结合寡聚化结构域样受体蛋白1(NLRP1)、黑色素瘤缺乏因子2(AIM2)、核苷酸结合寡聚化结构域样受体蛋白4(NLRC4)蛋白表达。结果 给药后,与空白组比较,模型组体质量下降,糖水偏好率降低,游泳不动时间延长,脑皮质神经元受到破坏,脑皮质IL-4含量降低,脑皮质IL-23、IL-27含量升高,脑皮质NLRP1、AIM2、NLRC4蛋白表达升高(均P<0.01)。与模型组比较,各给药组大鼠体质量上升,糖水偏好率增加,游泳不动时间缩短,脑皮质神经元受损情况好转,脑皮质IL-4含量增加,脑皮质IL-23、IL-27含量降低,脑皮质NLRP1、AIM2、NLRC4蛋白表达下降(均P<0.05)。结论 人参-玉竹药对能够改善慢性应激大鼠抑郁样行为,发挥抗抑郁作用,其机制可能与抑制脑皮质NLRP1、NLRC4、AIM2炎性小体激活及其介导的炎症反应,减少促炎细胞因子,提高抗炎细胞因子水平有关。

Objective To observe the effect of Renshen(ginseng)-Yuzhu(fragrant solomonseal rhizome) on inflammatory factors and inflammasomes in depression rats,and to explore the antidepressant mechanism of Renshen-Yuzhu.Methods Fifty male SD rats were divided into the blank group,model group,fluoxetine group(2.1 mg/kg),Renshen-Yuzhu low-dose group(1.89 g/kg),and Renshen-Yuzhu high-dose group(5.67 g/kg),with ten rats in each group.Except for the blank group,the rats in the other groups were treated with chronic unpredictable mild stress to establish a depression rat model.On the second day after the end of modeling,the rats in each group were given the corresponding drugs once daily for 14 days.After modeling and dosing,body weight,forced swimming immobility time,and sucrose preference rate were measured.After dosing,hematoxylin-eosin staining was used to detect neuronal damage in the cerebral cortex,enzyme-linked immunosorbent assay was used to detect the contents of interleukin-4(IL-4),interleukin-23(IL-23),and interleukin-27(IL-27) in cortex,real-time PCR was used to detect the mRNA expression of interleukin-24(IL-24) in cortex,and the protein expressions of nucleotide-binding oligomerization domain-like receptor protein 1(NLRP1),absent in melanoma 2(AIM2),and nucleotide-binding oligomerization domain-like receptor protein 4(NLRC4) were detected by Western blotting.Results After dosing,compared with the blank group,the body weight of the model group decreased,the sucrose preference rate decreased,the swimming immobility time was prolonged,the neuronal tissue in cortex was destroyed,the content of IL-4 in cortex decreased,the contents of IL-23 and IL-27 in cortex increased,and the protein expressions of NLRP1,AIM2 and NLRC4 in cortex increased(P<0.01).Compared with the model group,the body weight of rats in each administration group increased,the sucrose preference rate increased,the swimming immobility time was shortened,the damage of neuronal tissues in cortex improved,the content of IL-4 in cortex increased,the contents of IL-23 and IL-27 in cortex decreased,and the protein expressions of NLRP1,AIM2 and NLRC4 in cortex decreased(P<0.05).Conclusion Renshen-Yuzhu couplet medicines can improve the depressive-like behavior and exert antidepressant effect in chronic stress rats,and its mechanism may be related to the inhibition of NLRP1,NLRC4,AIM2 inflammasome activation and its mediated inflammatory response in cortex,reducing pro-inflammatory cytokines,and increasing the level of antiinflammatory cytokines.