Department of Oncology and Metabolism, University of Sheffield, Sheffield, United Kingdom.
Front Immunol. 2020 Sep 10;11:2184. doi: 10.3389/fimmu.2020.02184. eCollection 2020.
The gut and genital tract microbiota of females represent very complex biological ecosystems that are in continuous communication with each other. The crosstalk between these two ecosystems impacts host physiological, immunological and metabolic homeostasis and vice versa. The vaginal microbiota evolved through a continuous translocation of species from the gut to the vagina or through a mother-to-child transfer during delivery. Though the organisms retain their physio-biochemical characteristics while in the vagina, the immune responses elicited by their metabolic by-products appear to be at variance with those in the gut. This has critical implications for the gynecological, reproductive as well as overall wellbeing of the host and by extension her offspring. The homeostatic and immunomodulatory effects of the bacterial fermentation products (short chain fatty acids, SCFAs) in the gut are better understood compared to the genital tract. While gut SCFAs prevent a leakage of bacteria and bacterial products from the gut in to circulation (leaky gut) and consequent systemic inflammation (anti-inflammatory/protective role); they have been shown to exhibit dysbiotic and proinflammatory effects in the genital tract that can lead to unfavorable gynecological and reproductive outcomes. Therefore, this review was conceived to critically examine the correlation between the female gut and genital tract microbiota. Secondly, we explored the metabolic patterns of the respective microbiota niches; and thirdly, we described the diverse effects of products of bacterial fermentation on immunological responses in the vaginal and rectal ecosystems.
女性的肠道和生殖道微生物群代表着非常复杂的生物生态系统，它们之间不断地相互交流。这两个生态系统之间的相互作用会影响宿主的生理、免疫和代谢稳态，反之亦然。阴道微生物群通过物种从肠道到阴道的连续转移或通过分娩时的母婴转移而进化。尽管这些生物在阴道中保留了它们的生理生化特征，但它们的代谢产物引起的免疫反应似乎与肠道中的不同。这对宿主的妇科、生殖以及整体健康，以及她的后代都有至关重要的影响。与生殖道相比，肠道细菌发酵产物（短链脂肪酸，SCFAs）的稳态和免疫调节作用得到了更好的理解。虽然肠道 SCFAs 可以防止细菌和细菌产物从肠道漏入循环（漏肠）并导致全身炎症（抗炎/保护作用）；但它们已被证明在生殖道中表现出菌群失调和促炎作用，可能导致不良的妇科和生殖结局。因此，本综述旨在批判性地检查女性肠道和生殖道微生物群之间的相关性。其次，我们探讨了各自微生物群生态位的代谢模式；第三，我们描述了细菌发酵产物对阴道和直肠生态系统免疫反应的多种影响。
