Imbalances of the microbiome, also referred to as microbial dysbiosis, could lead to a series of different diseases. One factor that has been shown to lead to dysbiosis of the microbiome is exposure to psychological stressors. Throughout evolution microorganisms of the human microbiome have developed systems for sensing host-associated signals such as hormones associated with those stressors, enabling them to recognize essential changes in their environment, thus changing their expression gene profile to fit the needs of the new environment. The most widely accepted theory explaining the ability of hormones to affect the outcome of an infection involves the suppression of the immune system. Commensal microbiota is involved in stressor-induced immunomodulation, but other biological effects are not yet known. Here we present the impact that cortisol had on the community-wide transcriptome of the oral community. We used a metatranscriptomic approach to obtain first insights into the metabolic changes induced by this stress hormone as well as which members of the oral microbiome respond to the presence of cortisol in the environment. Our findings show that the stress hormone cortisol directly induces shifts in the gene expression profiles of the oral microbiome that reproduce results found in the profiles of expression of periodontal disease and its progression.

微生物组的失衡，也称为微生物营养不良，可能导致一系列不同的疾病。已显示导致微生物组营养不良的一个因素是暴露于心理压力源。在整个进化过程中，人类微生物组中的微生物已开发出可感测与宿主相关的信号（例如与那些应激源相关的激素）的系统，从而使它们能够识别环境中的重要变化，从而改变其表达基因谱以适应新环境的需求。解释激素影响感染结果的能力的最广泛接受的理论涉及免疫系统的抑制。共生微生物群参与应激源诱导的免疫调节，但其他生物学效应尚不明确。在这里，我们介绍了皮质醇对口腔社区的整个社区转录组的影响。我们使用了一种转录组学方法来获得由这种应激激素引起的代谢变化以及口腔微生物组的哪些成员对环境中皮质醇的存在做出反应的初步见解。我们的发现表明，应激激素皮质醇直接诱导口腔微生物组基因表达谱的变化，该变化再现了在牙周疾病表达谱及其进展中发现的结果。