Krania F, Dovolou E, Rekkas C A, Theodosiadou E K, Pappas I, Amiridis G S
Clinic of Obstetrics and Reproduction, Veterinary Faculty, University of Thessaly, Karditsa, Greece.
Reprod Domest Anim. 2015 Feb;50(1):112-20. doi: 10.1111/rda.12456. Epub 2014 Nov 18.
Plasminogen activators/Plasmin system plays pivotal role in regulating reproductive functions of mammals. Here, we examined the effects of modification of in vitro fertilization medium (IVF medium) with the addition of tissue-type plasminogen activator (t-PA), on bovine embryo development and quality, assessed by quantification of expression of various genes related to metabolism, oxidation, implantation and apoptosis. In addition, plasminogen activator activity (PAA) and plasminogen activator inhibition (PAI) were measured in the spent media. After conventional IVM, 2016 cumulus-oocyte complexes (COCs) were divided into four groups with modified composition of the IVF medium containing t-PA and/or its inhibitor epsilon-aminocaproic acid (control, t-PA, t-PA+ε-ACA, ε-ACA). Presumptive zygotes were cultured for 8 days in synthetic oviductal fluid (SOF) medium; gene expression studies were carried out on morulae and blastocysts. t-PA alone significantly suppressed cleavage and blastocyst formation rates, but this effect was neutralized by the addition of ε-ACA. PAA in the treated group was significantly reduced by ε-ACA, but without total elimination. Significant differences were detected in the expression of genes related to apoptosis and/or cell cycle arrest (BAX, BCL2L1, KAT2B) between embryos produced in t-PA-modified media and controls, giving an overall notion that the inferior developmental competence of treated embryos may be attributed to apoptotic phenomena induced by t-PA. In conclusion, it appears that excessive t-PA content in the IVF media, suppresses blastocyst formation rate, possibly due to induction of apoptotic phenomena.
纤溶酶原激活剂/纤溶酶系统在调节哺乳动物生殖功能中起关键作用。在此，我们研究了在体外受精培养基（IVF培养基）中添加组织型纤溶酶原激活剂（t-PA）对牛胚胎发育和质量的影响，通过定量与代谢、氧化、着床和凋亡相关的各种基因的表达来评估。此外，还测量了用过的培养基中的纤溶酶原激活剂活性（PAA）和纤溶酶原激活剂抑制（PAI）。常规体外成熟后，将2016个卵丘-卵母细胞复合体（COCs）分为四组，IVF培养基的组成进行了修改，含有t-PA和/或其抑制剂ε-氨基己酸（对照组、t-PA组、t-PA + ε-ACA组、ε-ACA组）。将假定的受精卵在合成输卵管液（SOF）培养基中培养8天；对桑葚胚和囊胚进行基因表达研究。单独使用t-PA显著抑制了卵裂率和囊胚形成率，但添加ε-ACA可中和这种作用。ε-ACA显著降低了处理组中的PAA，但并未完全消除。在t-PA修饰培养基中产生的胚胎与对照组之间，在与凋亡和/或细胞周期停滞相关的基因（BAX、BCL2L1、KAT2B）表达上检测到显著差异，总体表明处理后胚胎发育能力较差可能归因于t-PA诱导的凋亡现象。总之，IVF培养基中t-PA含量过高似乎会抑制囊胚形成率，可能是由于诱导了凋亡现象。
