seipin基因缺失损害卵巢卵泡发育的分子机制研究

先天性全身脂肪营养不良(CGL) II型是由于seipin基因缺失或无义突变所引起的常染色体遗传病。其主要临床特征为全身脂肪萎缩，胰岛素抵抗，伴有生殖功能异常。全身seipin基因敲除小鼠出现脂肪减少，胰岛素抵抗和卵泡发育障碍。通过制备选择性基因敲除小鼠，申请人的前期研究发现卵巢seipin缺失诱发窦状卵泡减少和闭锁卵泡增多，而脂肪细胞或神经系统seipin缺失都不影响卵泡发育。本研究目标是明确seipin缺失损害卵泡发育的分子机制，为CGL II型患者生殖异常的治疗提供新策略。申请人将从小鼠-卵巢-细胞水平通过选择性敲除seipin基因，系统地研究①seipin蛋白在各级卵泡的表达及其细胞的分布特征；②seipin缺失对整个卵泡发育过程的影响；③卵巢seipin缺失对卵泡PPARγ表达、Akt-mTOR和细胞凋亡信号通路、细胞自噬流、内质网应激等分子的影响以及调控机制。

Congenital generalized lipodystrophy (CGL) type II is an autosomal inherited disease caused by seipin gene deletion or nonsense mutation. Its main clinical features are systemic lipoatrophy, insulin resistance, and abnormal reproductive function. The whole body seipin knockout mice showed fat loss, insulin resistance and follicular development disorders. Through the preparation of selective gene knockout mice, the applicant’s preliminary study found that the absence of ovarian seipin induces antral follicle reduction and increased atretic follicles, while the absence of fat cells or nervous system seipin does not affect follicular development. The objective of this study is to clarify the molecular mechanism of seipin deficiency impairing follicular development, and to provide a new strategy for the treatment of reproductive abnormalities in CGL II patients. The applicant will use selectively knocking out the seipin gene, systematically study the following questions from the mouse-ovary-cell level: ① the expression of seipin protein at all levels of follicles and its cell distribution characteristics; ② the effect of seipin deficiency on the entire follicular development process; ③ the effects of ovarian seipin deficiency on the expression of follicle PPARγ, Akt-mTOR and apoptosis signal pathway, autophagy flow, endoplasmic reticulum stress and other molecules and its regulatory mechanism.