Abstract：
Leukaemia inhibitory factor (LIF) is a cytokine belonging to the interleukin-6 family that is important at the reproductive level in the uterine implantation process. However, there is very little evidence regarding its effect at the ovarian level. The aim of this work was to study the local involvement of the LIF/LIFRβ system in follicular development and steroidogenesis in rat ovaries. To carry out this research, LIF/LIFR/GP130 transcript and protein levels were measured in fertile and sub-fertile rat ovaries, and in vitro experiments were performed to assess STAT3 activation. Then, in in vivo experiments, LIF was administered chronically and locally for 28 days to the ovaries of rats by means of an osmotic minipump to enable us to evaluate the effect on folliculogenesis and steroidogenesis. It was determined by quantitative polymerase chain reaction and western blot that LIF and its receptors are present in fertile and sub-fertile ovaries and that LIF varies during the oestrous cycle, being higher during the oestrus and meta/dioestrus stages. In addition to this, it was found that LIF can activate STAT3 pathways and cause pSTAT3 formation. It was also observed that LIF decreases the number and size of preantral and antral follicles without altering the number of atretic antral follicles and can increase the number of corpora lutea, with a notable increase in the levels of progesterone (P4). It is therefore possible to infer that LIF exerts an important effect in vivo on folliculogenesis, ovulation and steroidogenesis, specifically the synthesis of P4.
摘要：
白血病抑制因子（LIF）是属于IL-6家族的细胞因子，在子宫植入过程中在生殖水平上很重要。然而,关于其在卵巢水平的作用的证据很少。这项工作的目的是研究LIF/LIFRβ系统在大鼠卵巢卵泡发育和类固醇生成中的局部参与。为了进行这项研究，LIF/LIFR/GP130转录物和蛋白质水平在可育和亚可育大鼠卵巢中测量，并进行体外实验以评估STAT3的激活。然后，在体内实验中，通过渗透微型泵将LIF长期和局部施用于大鼠卵巢28天，以使我们能够评估对卵泡生成和类固醇生成的影响。通过q-PCR和WB确定LIF及其受体存在于可育和亚可育卵巢中，LIF在发情周期中变化，在发情期和中/发情期阶段更高。除此之外,发现LIF可以激活STAT3通路并引起pSTAT3的形成。还观察到LIF减少了窦前和窦卵泡的数量和大小，而不改变闭锁的窦卵泡的数量。可以增加黄体的数量，孕酮水平显着增加。因此，可以推断LIF在体内对卵泡发生具有重要作用，排卵和类固醇生成，特别是黄体酮的合成。
