目的:本研究旨在阐明间充质干细胞(MSCs)如何通过PI3K-AKT通路调节线粒体动力学,有效减轻来曲唑诱导的多囊卵巢综合征(PCOS)的病理变化。
方法:32只雌性大鼠随机分为4个实验组,PCOS,PCOS+MSCs,和PCOS+MSCs+LY294002。Sham组接受0.5%w/v羧甲基纤维素(CMC);PCOS组接受来曲唑(1mg/kg,每天)在0.5%CMC中21天。PCOS+MSC组中的动物接受1×106个MSC/大鼠(i.p,)在研究的第22天。在PCOS+MSCs+LY294002组中,大鼠在MSC移植前40分钟接受LY294002(PI3K-AKT抑制剂)。线粒体动态基因表达,线粒体膜电位(MMP),柠檬酸合酶(CS)活性,氧化应激,炎症,卵巢组织学参数,血清激素水平,胰岛素抵抗的稳态模型评估(HOMA-IR),胰岛素和葡萄糖浓度,在实验结束时评估p-PI3K和p-AKT蛋白水平。
结果:PCOS大鼠显示线粒体动力学和组织学改变的显著破坏,降低MMP,CS,卵巢超氧化物歧化酶(SOD)和雌激素水平。他们的胰岛素和葡萄糖浓度也有显著上升,HOMA-IR,睾酮水平,肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)水平,与Sham组相比,卵巢丙二醛(MDA)含量以及p-PI3K和p-AKT蛋白水平显着降低。在PCOS+MSCs组中,MSCs移植可以改善上述参数。施用LY294002(PI3K-AKT通路抑制剂)使线粒体动态标志物恶化,氧化应激状态,炎症标志物,荷尔蒙水平,葡萄糖,与PCOS+MSCs组相比,胰岛素水平和卵泡发育。
结论:这项研究表明,MSC移植在调节线粒体动力学方面具有保护作用,促进线粒体生物发生,在PCOS模型中,与氧化还原状态和炎症反应的竞争主要通过PI3K-AKT通路介导.
OBJECTIVE: The present study aimed to elucidate how mesenchymal stem cells (MSCs) application could efficiently attenuate pathological changes of letrozole-induced poly cystic ovary syndrome (PCOS) by modulating mitochondrial dynamic via PI3K-AKT pathway.
METHODS: Thirty-two female rats were randomly divided into four experimental groups: Sham, PCOS, PCOS + MSCs, and PCOS + MSCs + LY294002. The Sham group received 0.5% w/v carboxymethyl cellulose (CMC); the PCOS group received letrozole (1 mg/kg, daily) in 0.5% CMC for 21 days. Animals in the PCOS + MSCs group received 1 × 106 MSCs/rat (i.p,) on the 22th day of the study. In the PCOS + MSCs + LY294002 group, rats received LY294002 (PI3K-AKT inhibitor) 40 min before MSC transplantation. Mitochondrial dynamic gene expression, mitochondrial membrane potential (MMP), citrate synthase (CS) activity, oxidative stress, inflammation, ovarian histological parameters, serum hormone levels, homeostatic model assessment for insulin resistance (HOMA-IR), insulin and glucose concentrations, p-PI3K and p-AKT protein levels were evaluated at the end of the experiment.
RESULTS: PCOS rats showed a significant disruption of mitochondrial dynamics and histological changes, lower MMP, CS, ovary super oxide dismutase (SOD) and estrogen level. They also had a notable rise in insulin and glucose concentrations, HOMA-IR, testosterone level, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels, ovarian malondialdehyde (MDA) content as well as a notable decrease in p-PI3K and p-AKT protein levels compared to the Sham group. In the PCOS + MSCs group, the transplantation of MSCs could improve the above parameters. Administration of LY294002 (PI3K-AKT pathway inhibitor) deteriorated mitochondrial dynamic markers, oxidative stress status, inflammation markers, hormonal levels, glucose, and insulin levels and follicular development compared to the PCOS + MSCs group.
CONCLUSIONS: This study demonstrated that the protective effects of MSC transplantation in regulating mitochondrial dynamics, promoting mitochondrial biogenesis, competing with redox status and inflammation response were mainly mediated through the PI3K-AKT pathway in the PCOS model.