Slot Karin A, Voorendt Marsha, de Boer-Brouwer Mieke, van Vugt Harmke H, Teerds Katja J
Department of Biochemistry & Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3508 TD Utrecht, The Netherlands.
J Endocrinol. 2006 Feb;188(2):179-92. doi: 10.1677/joe.1.06165.
In the present investigation, the localization of proteins involved in ovarian apoptosis were studied throughout the estrous cycle in the presence of fluctuating hormone levels. Fas, Fas ligand, Bcl-2, Bax and caspase-3 mRNA expression and proteins were detected in all ovarian tissue extracts, though the amount of protein varied with the phase of the estrous cycle. Fas, Bax and caspase-3 protein levels were highest at diestrus and decreased thereafter towards metestrus. In contrast, Fas ligand and Bcl-2 protein levels were lowest at diestrus and increased toward metestrus. Immunohistochemistry revealed that the staining of the anti-apoptotic protein Bcl-2 was more pronounced in healthy preantral follicles than in atretic follicles. In contrast, the pro-apoptotic proteins Fas, Fas ligand, Bax and active caspase-3 were more predominantly present in atretic follicles. In the ovarian surface epithelium (OSE), Fas, procaspase-3 and Bcl-2 immunostaining appeared independent of the phase of the estrous cycle. Fas ligand and Bax staining was detected particularly during proestrus in OSE cells surrounding the ovulatory follicles, while active caspase-3 was observed only in OSE cells at the postovulatory site during estrus. The proportion of luteal cells that stained positively for Fas, Bax and caspase-3 increased with the age of the corpus luteum, while Fas ligand and Bcl-2 immunostaining was strongest in newly formed corpora lutea and decreased thereafter. In conclusion, the components of the Fas signalling pathway were differentially expressed throughout the estrous cycle in a variety of ovarian cell types, which may correspond to hormone dependent survival mechanisms.
在本研究中，在激素水平波动的情况下，研究了发情周期中参与卵巢细胞凋亡的蛋白质的定位。在所有卵巢组织提取物中均检测到Fas、Fas配体、Bcl-2、Bax和caspase-3的mRNA表达及蛋白质，不过蛋白质的量随发情周期的阶段而变化。Fas、Bax和caspase-3的蛋白质水平在动情后期最高，此后向动情后期降低。相反，Fas配体和Bcl-2的蛋白质水平在动情后期最低，并向动情后期升高。免疫组织化学显示，抗凋亡蛋白Bcl-2在健康的窦前卵泡中的染色比在闭锁卵泡中更明显。相反，促凋亡蛋白Fas、Fas配体、Bax和活性caspase-3更多地存在于闭锁卵泡中。在卵巢表面上皮（OSE）中，Fas、procaspase-3和Bcl-2的免疫染色似乎与发情周期的阶段无关。Fas配体和Bax染色尤其在排卵前卵泡周围的OSE细胞发情前期被检测到，而活性caspase-3仅在发情期排卵后部位的OSE细胞中观察到。Fas、Bax和caspase-3染色呈阳性的黄体细胞比例随黄体年龄增加，而Fas配体和Bcl-2免疫染色在新形成的黄体中最强，此后降低。总之，Fas信号通路的成分在发情周期中在多种卵巢细胞类型中差异表达，这可能与激素依赖性存活机制相对应。
