Analysis of intestinal flora in Mongolian female students under anxiety in a medical university

Abstract

Objective To investigate the change in intestinal flora in Mongolian students with anxiety, so as to provide basis for exploring the relationship between flora and secretion expression in vivo.

Methods The Self-rating Anxiety Scale (SAS) was used to assess anxiety in medical college students; then a semi-structured interview was administered. Fecal samples that met the inclusion criteria were collected and divided into anxiety (SAS score≥50) and control groups (no anxiety, SAS score<50) according to the standard score of SAS. Samples provided by Mongolian female students were selected from each group. The total bacterial DNA was extracted from the fecal samples for PCR amplification and NovaSeq 2x250bp high-throughput sequencing was performed for the V3-V4 region of 16S rDNA gene to obtain the biological information of the intestinal flora. The intergroup OTU, structural diversity, significant difference, and LEfSe analyses were performed with information mining of the literature think tanks.

Results Anxiety existed in 23.86% of the Mongolian students, and 16.96% of the Han people. A Chi-square test showed no significant difference in detection of anxiety between Mongolian and Han college students ( P=0.07). Analysis of the alpha diversity index showed that the Shannon index, Simpson index, Chao1 index, and Observed species did not differed significantly between the two groups ( t=8.0, 9.0, 6.0, 6.5). The difference in abundance of some bacteria was significant at the Class, Order, Family, and Genus levels between the two groups ( t=−2.26–2.57, −5.08–3.58, −2.65–2.09, P<0.05).

Conclusion The alpha diversity index showed that there was no significant difference in the abundance and diversity of intestinal flora between the two groups. While there were significant differences at different classification levels, the results suggest that the structure of intestinal flora can change in students with anxiety.

Abstract

【摘要】 目的 探讨蒙古族学生焦虑情绪下肠道菌群变化, 为探究体内菌群与分泌物表达之间的关系提供依据。 方法 通过焦虑自评量表及半结构化访谈对某医学髙校 454 名大学生焦虑情况展开调査, ≥50 分者为焦虑情绪组、<50 分者为对 照组 (无焦虑情绪组), 收取符合纳人标准且同意取样的被试粪便样本, 从两组中选取蒙古族女生提供的样本。收集每份 粪便样品的细菌总 DNA 进行 PCR 扩增, 针对 16S rDNA V3~V4 区进行 NovaSeq 2x250bp 髙通量测序, 并进行组间OTU分 析、样品多样性分析、样品组间差异分析及LEfSe分析。 结果 蒙古族医学生焦虑检出率为 23.86%, 汉族学生焦虑检出率 为 16.96%, 差异无统计学意义 ( P=0.07); 组间Alpha多样性指数分析显示, Shannon、 Simpson、 Chao1、 Observed species 指数在 女生焦虑情绪组与对照组组间差异无统计学意义 ( t 值分别为 8.0, 9.0, 6.0, 6.5, P 值均>0.05)。在纲、目, 科, 属、种水平上, 焦虑情绪组与对照组在某些物种上差异有统计学意义 ( t=−2.26~2.57, −5.08~3.58, −2.65~2.09, P 值均<0.05)。 结论 Alpha多样性指数显示焦虑情绪组与对照组肠道群落丰富度和多样性无差异, 但两组在不同分类水平上均存在差异物种, 提示焦虑情绪状态下肠道菌群结构会改变, 肠道菌群与焦虑情绪存在一定关联。