Wang F, Zhang Z, Sun Y, Yang L, Guo T, Pan Y, Ding S, Jiang L, Liu H
Laboratory of Tissue and Cell Biology, Experimental Teaching and Management Center, Chongqing Medical University, Chongqing 400016, China.
Department of Center for Neuroscience Research, Chongqing Medical University, Chongqing 400016, China.
Nan Fang Yi Ke Da Xue Xue Bao. 2024 May 20;44(5):876-884. doi: 10.12122/j.issn.1673-4254.2024.05.09.
To investigate the mechanisms that mediate the neuroprotective effect of the intestinal microbial metabolite sodium butyrate (NaB) in a mouse model of Parkinson's disease (PD) the gut-brain axis.
Thirty-nine 7-week-old male C57BL/6J mice were randomized equally into control group, PD model group, and NaB treatment group. In the latter two groups, PD models were established by intraperitoneal injection of 30 mg/kg 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) once daily for 5 consecutive days, and normal saline was injected in the control group. After modeling, the mice received daily gavage of NaB (300 mg/kg) or an equal volume of saline for 14 days. Behavioral tests were carried out to assess the changes in motor function of the mice, and Western blotting was performed to detect the expressions of tyrosine hydroxylase (TH) and -synuclein (-syn) in the striatum and nuclear factor-κB (NF-κB), tumor necrosis factor (TNF-), interleukin 6 (IL-6), and the tight junction proteins ZO-1, Occludin, and Claudinin the colon. HE staining was used to observe inflammatory cell infiltration in the colon of the mice. RNA sequencing analysis was performed to identify the differentially expressed genes in mouse colon tissues, and their expressions were verified using qRT-PCR and Western blotting.
The mouse models of PD with NaB treatment showed significantly increased movement speed and pulling strength of the limbs with obviously upregulated expressions of TH, Occludin, and Claudin and downregulated expressions of -syn, NF-κB, TNF-, and IL-6 (all < 0.05). HE staining showed that NaB treatment significantly ameliorated inflammatory cell infiltration in the colon of the PD mice. RNA sequencing suggested that Bmal1 gene probably mediated the neuroprotective effect of NaB in PD mice ( < 0.05).
NaB can improve motor dysfunction, reduce dopaminergic neuron loss in the striatum, and ameliorate colonic inflammation in PD mice possibly through a mechanism involving Bmal1.
研究肠道微生物代谢产物丁酸钠(NaB)在帕金森病(PD)小鼠模型中通过肠-脑轴介导神经保护作用的机制。
将39只7周龄雄性C57BL/6J小鼠随机等分为对照组、PD模型组和NaB治疗组。后两组通过腹腔注射30 mg/kg 1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP),每天1次,连续5天建立PD模型,对照组注射生理盐水。造模后,小鼠每天灌胃NaB(300 mg/kg)或等体积生理盐水,共14天。进行行为测试以评估小鼠运动功能的变化,采用蛋白质免疫印迹法检测纹状体中酪氨酸羟化酶(TH)和α-突触核蛋白(α-syn)以及结肠中核因子κB(NF-κB)、肿瘤坏死因子(TNF-α)、白细胞介素6(IL-6)和紧密连接蛋白ZO-1、闭合蛋白(Occludin)、Claudin的表达。采用苏木精-伊红(HE)染色观察小鼠结肠的炎性细胞浸润情况。进行RNA测序分析以鉴定小鼠结肠组织中差异表达的基因,并通过实时定量聚合酶链反应(qRT-PCR)和蛋白质免疫印迹法验证其表达。
接受NaB治疗的PD小鼠模型显示运动速度和肢体拉力显著增加,TH、Occludin和Claudin的表达明显上调,α-syn、NF-κB、TNF-α和IL-6的表达下调(均P<0.05)。HE染色显示,NaB治疗显著改善了PD小鼠结肠的炎性细胞浸润。RNA测序表明,Bmal1基因可能介导了NaB对PD小鼠的神经保护作用(P<0.05)。
NaB可能通过涉及Bmal1的机制改善PD小鼠的运动功能障碍,减少纹状体中多巴胺能神经元的损失,并减轻结肠炎症。