Laboratory of Animal Reproduction, Department of Biological Sciences, Biomaterials Research Cluster, Bernal Institute, Faculty of Science and Engineering, University of Limerick, Limerick, Ireland.
Animal & Bioscience Research Department, Teagasc Animal & Grassland Research and Innovation Centre, Grange, Dunsany, Co., Meath, Ireland.
Biol Reprod. 2023 Jun 9;108(6):912-921. doi: 10.1093/biolre/ioad031.
Despite stringent quality control checks, some bulls with apparently normal semen quality yield lower than expected pregnancy rates. This study profiled the transcriptome and performed histological analysis of the bovine uterus in response to sperm from high-fertility (HF) and low-fertility (LF) bulls. Postmortem uterine biopsies and uterine explants were collected from heifers 12 h after a fixed time artificial insemination (AI) to a synchronized estrus with frozen-thawed semen from five HF (fertility rate 4.01% ± 0.25) and five LF (fertility rate - 11.29% ± 1.11; mean ± SEM) bulls. Uterine biopsies were also collected from control (CTRL) heifers, which were not inseminated. RNA-sequencing and histological analysis were performed for differential gene expression and neutrophil quantification. In the HF treatment relative to CTRL heifers, there were 376 genes significantly differentially expressed in the endometrium with just one gene differentially expressed in the LF treatment relative to CTRL heifers. Comparing the HF and LF treatments directly, there were 40 significantly differentially expressed genes (P < 0.05). Transcriptomic analysis shows a predominant role for the inflammatory marker Interleukin-1 alpha, which was further confirmed by immunohistochemistry. Quantification of neutrophils in the endometrium showed a significant effect of sperm; however, there was no difference in neutrophil numbers between HF and LF groups. In conclusion, this novel study clearly shows a distinct inflammatory response to sperm in the endometrium and a divergent transcriptomic response to semen from HF and LF bulls.
尽管进行了严格的质量控制检查，但一些精液质量看似正常的公牛的受胎率却低于预期。本研究对高生育力（HF）和低生育力（LF）公牛的精子进行了转录组分析，并对牛子宫进行了组织学分析。在通过固定时间人工授精（AI）同步发情后 12 小时，从小母牛中采集死后子宫活检和子宫外植体，用来自五头 HF（受精率 4.01%±0.25）和五头 LF（受精率-11.29%±1.11；平均值±SEM）公牛的冷冻解冻精液进行 AI。还从小牛中采集了未进行授精的对照（CTRL）子宫活检。进行 RNA 测序和组织学分析，以检测差异基因表达和中性粒细胞定量。与 CTRL 小母牛相比，HF 处理组子宫内膜中 376 个基因表达显著差异，而 LF 处理组仅一个基因表达差异。直接比较 HF 和 LF 处理组，有 40 个基因表达显著差异（P<0.05）。转录组分析显示炎症标志物白细胞介素 1 阿尔法（Interleukin-1 alpha）起着主要作用，免疫组织化学进一步证实了这一点。子宫内膜中性粒细胞的定量显示精子有显著影响；然而，HF 和 LF 组之间的中性粒细胞数量没有差异。总之，这项新的研究清楚地表明，子宫内膜对精子有明显的炎症反应，而对 HF 和 LF 公牛精液的转录组反应则不同。
