Pacella-Ince Leanne, Zander-Fox Deirdre L, Lane Michelle
University of Adelaide, Medical School South, Level 3. Frome Rd, Adelaide, SA 5000, Australia.
Reprod Fertil Dev. 2014 Oct;26(8):1072-83. doi: 10.1071/RD13178.
Women with reduced ovarian reserve or advanced maternal age have an altered metabolic follicular microenvironment. As sirtuin 5 (SIRT5) senses cellular metabolic state and post-translationally alters protein function, its activity may directly impact on oocyte viability and pregnancy outcome. Therefore, we investigated the role of SIRT5 in relation to ovarian reserve and maternal age. Women (n=47) undergoing routine IVF treatment were recruited and allocated to one of three cohorts based on ovarian reserve and maternal age. Surplus follicular fluid, granulosa and cumulus cells were collected. SIRT5 mRNA, protein and protein activity was confirmed in granulosa and cumulus cells via qPCR, immunohistochemistry, western blotting and desuccinylation activity. The presence of carbamoyl phosphate synthase I (CPS1), a target of SIRT5, was investigated by immunohistochemistry and follicular-fluid ammonium concentrations determined via microfluorometry. Women with reduced ovarian reserve or advanced maternal age had decreased SIRT5 mRNA, protein and desuccinylation activity in granulosa and cumulus cells resulting in an accumulation of follicular-fluid ammonium, presumably via alterations in activity of a SIRT5 target, CPS1, which was present in granulosa and cumulus cells. This suggests a role for SIRT5 in influencing oocyte quality and IVF outcomes.
卵巢储备功能减退或高龄产妇的代谢性卵泡微环境会发生改变。由于沉默调节蛋白5（SIRT5）可感知细胞代谢状态并在翻译后改变蛋白质功能，其活性可能直接影响卵母细胞的活力和妊娠结局。因此，我们研究了SIRT5在卵巢储备和产妇年龄方面的作用。招募了接受常规体外受精治疗的女性（n = 47），并根据卵巢储备和产妇年龄将其分配到三个队列之一。收集多余的卵泡液、颗粒细胞和卵丘细胞。通过定量聚合酶链反应、免疫组织化学、蛋白质印迹法和去琥珀酰化活性，在颗粒细胞和卵丘细胞中证实了SIRT5信使核糖核酸、蛋白质和蛋白质活性。通过免疫组织化学研究了SIRT5的靶标氨基甲酰磷酸合成酶I（CPS1）的存在情况，并通过微量荧光测定法测定了卵泡液铵浓度。卵巢储备功能减退或高龄产妇的颗粒细胞和卵丘细胞中SIRT5信使核糖核酸、蛋白质和去琥珀酰化活性降低，导致卵泡液铵积累，推测这是由于SIRT5靶标CPS1的活性改变所致，CPS1存在于颗粒细胞和卵丘细胞中。这表明SIRT5在影响卵母细胞质量和体外受精结局方面发挥作用。
