犬黄体功能调控机制研究进展

犬黄体具有异于其他家畜的生理结构和功能表现,其中最特别的是犬缺乏急性黄体溶解机制。犬黄体发生过程受催乳素、促黄体素和前列腺素E₂的复杂调控,溶解退化过程则对其他家畜主要的溶黄体激素--前列腺素F_2α不敏感。而黄体的存留对母犬的生殖活动却具有重要的意义,其自分泌或旁分泌的类固醇激素也在妊娠调控和发情周期的更迭中发挥重要作用。犬黄体的退化机制尚未明确,但国外已有包括被动退化在内的诸多假说。此外,黄体是为数不多具有完整生命周期的功能性组织（或器官）,其发生过程、功能实现和衰老溶解都在周而复始地进行,这对炎症反应、癌症发生和细胞凋亡等研究都具有重要的参考价值。作者综述了犬黄体的发生和退化过程中调控机制的研究进展,旨在为进一步深入研究犬黄体发生和退化的分子机制提供研究背景和理论依据。     

牛优势卵泡膜细胞黄体化相关基因的筛选

【目的】探究牛卵巢小黄体细胞（SLCs）和膜细胞（TCs）中的差异表达基因,进而筛选与TCs黄体化密切相关的基因,为深入研究SLCs、TCs特异性及TCs向SLCs分化的机制提供参考。【方法】利用R软件limma包中的DESeq2,筛选GEO芯片数据库GSE83524数据集TCs和SLCs中的差异表达基因,再用goseq软件对筛选出的差异表达基因进行GO功能富集分析,用 kobas软件进行KEGG信号通路分析,使用String结合Cytoscape软件进行PPI网络互作分析。采集思南黄牛颗粒细胞(GCs)和TCs,以RPLP0作为内参基因,用荧光定量 PCR法对筛选出的与TCs增殖及黄体化相关的基因进行验证。【结果】共筛选获得237个差异表达基因,其中表达上调的基因115个,表达下调的基因122个。GO功能分析结果显示,参与生物学过程的有147个基因,占差异表达基因总数的53.6%,分别富集于30个组;参与细胞组分的有125个基因,占差异表达基因总数的21.4%,分别富集于12个组;参与分子功能的有98个基因,占差异表达基因总数的25.0%,分别富集于14个组。KEGG分析共发现17条通路,其中可能与卵泡内膜细胞黄体化相关的通路为FSHR、PLA2G4A、CYP19A1、CYP17A1等4个基因参与的卵巢类固醇生成通路。经过PPI网络互作分析,筛选出了前10位的hub基因。荧光定量 PCR分析结果显示,FSHR、PLA2G4A、CYP19A1、CYP17A1、BUB1B和KIF20A在SLCs和TCs中的转录水平与GEO芯片数据结果一致,表现为FSHR、CYP19A1和CYP17A1在TCs中的表达量极显著高于其在SLCs中的表达量(P<0.01),PLA2G4A、BUB1B和KIF20A在TCs中的表达量亦显著高于其在SLCs中的表达量 (P<0.05)。【结论】差异表达基因FSHR、PLA2G4A、CYP19A1、CYP17A1、BUB1B和KIF20A在牛优势卵泡TCs增殖分化形成黄体的过程中发挥关键作用。     

Research Progress on Regulatory Mechanisms of Canine Corpus Luteum Function

Significant differences can be found in the physiology construction and functional performance of canine corpus luteum from the other domestic animal species, and the most interesting characteristic is the lack of an acute luteolytic mechanism. It is a multifactorial process that luteinization of canine is regulated by PRL, LH and PGE₂, and the luteolysis is insensitive to PGF_2α. The remaining canine corpus luteum plays an important role in bitch reproductive activities, and the steroid hormone from it through autocrine or paracrine is the same important to pregnancy and the estrus cycle. It is still unknown about the mechanism of regression of canine corpus luteum, however, there are several hypotheses including the passive regression mechanism. Moreover, corpus luteum is one of the few tissues (organs) which includes all three parts formation, maintenance and regression of the life cycle, and it is very important for the research of inflammatory reaction, carcinogenesis and apoptosis. In this review, the advanced progress of formation and regression of canine corpus luteum were summarized, which would provide theoretical basis and research background to study the molecular mechanism in this filed.     

The Use of Epostane in an Attempt to Reproduce Cystic Endometrial Hyperplasia in the Bitch

The aetiology and pathogenesis of spontaneous cystic endometrial hyperplasia (CEH) in the bitch is not yet completely understood. Recent research based on the expression of uterine sex hormone receptors in spontaneous cases of CEH suggested that a temporary progesterone deficiency during late oestrus-early metoestrus may be responsible for the onset of CEH development. In the present study a temporary progesterone deficiency during late oestrus–early metoestrus was experimentally created using an inhibitor of progesterone synthesis, epostane. At day 49 of metoestrus, there was a significant reduction in the size of the uterine wall, mainly due to endometrial atrophy, and there was also a significant increase in the mucus-filled uterine lumen in the bitches that had been treated with epostane compared to the control bitches. No significant differences in the expression of sex hormone receptors was observed between the two groups. As no CEH developed in the epostane-treated bitches, an additional oestrogenic stimulus may be required to stimulate endometrial proliferation. Therefore, it is suggested that deficient luteinization of the corpus luteum may be the trigger in the pathogenesis of CEH, as the secretion of varying amounts of sex steroids depends on the degree of luteinization.