Department of Psychiatry, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, 453002, Henan, China.
Department of Psychiatry, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, 453002, Henan, China.
Microb Pathog. 2023 Mar;176:106008. doi: 10.1016/j.micpath.2023.106008. Epub 2023 Feb 2.
Anxiety disorder is highly prevalent worldwide and represents a chronic and functionally disabling condition, with high levels of psychological stress characterized by cognitive and physiological symptoms. The purpose of this study is to evaluate the clinical significance of gut microbiota regulating microRNA (miR)-206-3p as a biomarker in the anxiety-like behaviors.
Initially, bioinformatics analysis was performed to predict the related factors for gut microbiota affecting anxiety-like behaviors. Next, the anxiety-like behaviors in mice were measured by multiple experiments. Western blot analysis, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) were utilized to measure the levels of 5-hydroxytryptamine (5-HT), brain derived neurotrophic factor (BDNF), and neutrophil expressed (NE) in brain tissues and serum and cAMP responsive element binding protein 1 (CREB) phosphorylation in brain tissues of germ-free (GF) mice. Dual-luciferase reporter gene assay was employed to verify the relationship between miR-206-3p and Cbp/p300 interacting transactivator with Glu/Asp rich carboxy-terminal domain 2 (Cited2)/serine/threonine kinase 39 (STK39). Ectopic expression and depletion experiments of miR-206-3p were conducted to determine the expression of miR-206-3p and mRNA and protein levels of Cited2, and STK39 in HT22 cells and brain tissues. Finally, transmission electron microscope (TEM) was used to observe the effects of miR-206-3p on hippocampal mitochondria and synapses.
Gut microbiota could elevate miR-206-3p expression in brain tissues to increase the anxiety-like behaviors. GF mice displayed the increased levels of 5-HT, BDNF, and NE in brain tissues and serum and CREB phosphorylation in brain tissues. Cited2/STK39 was identified as the target genes of miR-206-3p. Upregulated miR-206-3p increased anxiety-like behaviors by promoting degeneration of mitochondria and synapses in hippocampus via downregulation of Cited2 and STK39.
In conclusion, the key findings of the current study demonstrate that gut microbiota aggravated anxiety-like behaviors via the miR-206-3p/Cited2/STK39 axis.
焦虑障碍在全球范围内普遍存在，是一种慢性且功能失调的疾病，具有高水平的心理压力，表现为认知和生理症状。本研究的目的是评估肠道微生物群调节 microRNA（miR）-206-3p 作为焦虑样行为生物标志物的临床意义。
首先，通过生物信息学分析预测影响焦虑样行为的肠道微生物群相关因素。然后，通过多项实验测量小鼠的焦虑样行为。采用 Western blot 分析、免疫组织化学和酶联免疫吸附试验（ELISA）测量无菌（GF）小鼠脑组织和血清中 5-羟色胺（5-HT）、脑源性神经营养因子（BDNF）和中性粒细胞表达（NE）水平，以及脑组织中环磷酸腺苷反应元件结合蛋白 1（CREB）磷酸化。双荧光素酶报告基因实验验证 miR-206-3p 与 Cbp/p300 相互作用的转录激活因子与 Glu/Asp 丰富的羧基末端域 2（Cited2）/丝氨酸/苏氨酸激酶 39（STK39）之间的关系。进行 miR-206-3p 的异位表达和耗竭实验，以确定 HT22 细胞和脑组织中 miR-206-3p 的表达以及 Cited2 和 STK39 的 mRNA 和蛋白水平。最后，使用透射电子显微镜（TEM）观察 miR-206-3p 对海马线粒体和突触的影响。
肠道微生物群可提高脑组织中 miR-206-3p 的表达，从而增加焦虑样行为。GF 小鼠表现出脑组织和血清中 5-HT、BDNF 和 NE 水平升高以及脑组织中 CREB 磷酸化升高。Cited2/STK39 被鉴定为 miR-206-3p 的靶基因。上调的 miR-206-3p 通过下调 Cited2 和 STK39 促进海马线粒体和突触退化，从而增加焦虑样行为。
总之，本研究的主要发现表明，肠道微生物群通过 miR-206-3p/Cited2/STK39 轴加重焦虑样行为。
