Gong Jianfei, Zhao Shanjiang, Heng Nuo, Wang Yi, Hu Zhihui, Wang Huan, Zhu Huabin
State Key Laboratory of Animal Nutrition, Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.
Front Vet Sci. 2022 Aug 5;9:915956. doi: 10.3389/fvets.2022.915956. eCollection 2022.
Ketosis is common in high-yield dairy cows. It is a condition that is characterized by the accumulation of serum β-hydroxybutyric acid (BHBA). Both subclinical ketosis and clinical ketosis can compromise the reproductive performance and cause long-lasting negative effects on reproductive efficiency by affecting the proliferation of follicular and granulosa cells. However, the regulatory mechanisms involved in the development of follicular cells and granulosa cells in cows experiencing subclinical ketosis and clinical ketosis remain largely unknown. To investigate the effect of a ketosis-triggered increase in BHBA on bovine follicular granulosa cell development, we detected a significant reduction in the proliferation of granulosa cells ( < 0.05) in the BHBA-1.2 m and BHBA-2.4 m groups and a significant increase in the number of granulosa cells in the G1 phase of the cell cycle ( < 0.05). RNA-seq and trend analysis were used to identify differentially expressed genes by comparing three clusters: low-concentration response to 1.2 m BHBA, high-concentration response to 2.4 m BHBA, and the similar trend (up or down) response following BHBA concentration increased. GO and KEGG enrichment analyses were performed separately for each cluster. Analysis showed that two novel down-regulated genes ( and ), which are associated with cell proliferation and cycle progression, were enriched in the low-concentration response to 1.2 m BHBA. Another differentially expressed gene (), which plays a role in the apoptotic pathway, was enriched in the high-concentration response to 2.4 m BHBA. We also found that and , which are associated with Ca homeostasis and estrogen synthesis, were enriched in a similar trend response. In conclusion, we describe the dynamic transcription profiles of granulosa cells under different levels of β-hydroxybutyric stress and report key regulators that may underlie the detrimental effects on the development of follicles and granulosa cells, thus representing potential therapeutic targets to improve fertility in dairy cows with subclinical ketosis or clinical ketosis.
酮病在高产奶牛中很常见。它是一种以血清β-羟基丁酸（BHBA）积累为特征的病症。亚临床酮病和临床酮病都会损害繁殖性能，并通过影响卵泡细胞和颗粒细胞的增殖对繁殖效率造成长期负面影响。然而，亚临床酮病和临床酮病奶牛卵泡细胞和颗粒细胞发育所涉及的调控机制在很大程度上仍不清楚。为了研究酮病引发的BHBA增加对牛卵泡颗粒细胞发育的影响，我们检测到BHBA-1.2 m组和BHBA-2.4 m组颗粒细胞增殖显著减少（<0.05），且细胞周期G1期颗粒细胞数量显著增加（<0.05）。通过比较三个聚类：对1.2 m BHBA的低浓度反应、对2.4 m BHBA的高浓度反应以及BHBA浓度增加后的相似趋势（上升或下降）反应，使用RNA测序和趋势分析来鉴定差异表达基因。对每个聚类分别进行GO和KEGG富集分析。分析表明，两个与细胞增殖和周期进展相关的新下调基因（和）在对1.2 m BHBA的低浓度反应中富集。另一个在凋亡途径中起作用的差异表达基因（）在对2.4 m BHBA的高浓度反应中富集。我们还发现，与钙稳态和雌激素合成相关的和在相似趋势反应中富集。总之，我们描述了不同水平β-羟基丁酸应激下颗粒细胞的动态转录谱，并报告了可能是卵泡和颗粒细胞发育有害影响基础的关键调节因子，从而代表了改善亚临床酮病或临床酮病奶牛繁殖力的潜在治疗靶点。
