da Silva-Álvarez Eva, Gómez-Arrones Vanessa, Correa-Fiz Florencia, Martín-Cano Francisco Eduardo, Gaitskell-Phillips Gemma, Carrasco Juan Jesús, Rey Joaquín, Aparicio Inés María, Peña Fernando Juan, Alonso Juan Manuel, Ortega-Ferrusola Cristina
Department of Animal Medicine, Laboratory of Equine Reproduction and Equine Spermatology, Faculty of Veterinary Medicine, University of Extremadura, Cáceres, Spain.
Centro de Selección y Reproducción animal de Extremadura. Junta de Extremadura, Badajoz, Spain.
PLoS One. 2025 Apr 16;20(4):e0321389. doi: 10.1371/journal.pone.0321389. eCollection 2025.
This study aims to unveil potential differences in the vaginal and uterine microbiomes in mares and jennies, and to identify possible mechanisms involved in uterine immune homeostasis. The microbiota was characterized using 16S rRNA sequencing, and the uterine proteome was analyzed using UHPLC/MS/MS in 18 samples from healthy mares and 14 from jennies. While taxonomic analysis revealed high interspecies similarities, β-diversity analysis showed distinct clustering, with only two vaginal taxa and five uterine taxa differing between species. Despite compositional differences, PICRUSt analysis suggested minimal variations in predicted functional pathways across species. Comparing vaginal and uterine microbiota within the same species revealed overlapping bacterial taxa, but significant differences in α- and β-diversity and functional pathways. The uterine microbiota of both species was dominated by Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, with abundant taxa like Streptococcus, Pseudomonas, Bacillus, Corynebacterium, and Staphylococcus, many of which are frequently associated with endometritis. The presence of Lactobacillus in the equine reproductive tract was minimal or non-existent. KEGG functional pathway analysis predicted that uterine microbiota of both species utilize metabolic pathways with potential immunomodulatory effects. Proteomic enrichment analysis showed that numerous overexpressed uterine proteins in both species are linked to adaptive and innate immune regulation and defense mechanisms against symbionts. Gene enrichment analysis identified several enriched Gene Ontology terms, including response to bacterial stimuli, humoral immune regulation, and TGF-beta receptor signaling, underscoring microbial-host interactions. The uterine microbiota may play a vital role in maintaining immune balance. Further research is required to confirm its interaction with the uterine immune system and clarify the mechanisms involved.
本研究旨在揭示母马和母驴阴道及子宫微生物群的潜在差异，并确定参与子宫免疫稳态的可能机制。使用16S rRNA测序对微生物群进行特征分析，并使用超高效液相色谱/串联质谱法（UHPLC/MS/MS）对18份健康母马样本和14份母驴样本的子宫蛋白质组进行分析。虽然分类分析显示种间相似度较高，但β多样性分析显示出明显的聚类，物种间仅两个阴道分类群和五个子宫分类群存在差异。尽管组成存在差异，但PICRUSt分析表明，跨物种预测的功能途径变化极小。比较同一物种内的阴道和子宫微生物群发现，细菌分类群存在重叠，但α和β多样性及功能途径存在显著差异。两个物种的子宫微生物群均以变形菌门、厚壁菌门、拟杆菌门和放线菌门为主，有大量如链球菌、假单胞菌、芽孢杆菌、棒状杆菌和葡萄球菌等分类群，其中许多常与子宫内膜炎相关。马生殖道中乳酸杆菌的存在极少或不存在。KEGG功能途径分析预测，两个物种的子宫微生物群利用具有潜在免疫调节作用的代谢途径。蛋白质组富集分析表明，两个物种中大量过表达的子宫蛋白与适应性和先天性免疫调节以及针对共生体的防御机制有关。基因富集分析确定了几个富集的基因本体术语，包括对细菌刺激的反应、体液免疫调节和转化生长因子-β受体信号传导，强调了微生物与宿主的相互作用。子宫微生物群可能在维持免疫平衡中发挥重要作用。需要进一步研究以确认其与子宫免疫系统的相互作用并阐明其中涉及的机制。
