一种新型脂肪来源多肽PDFAT2用于PCOS防治的应用基础研究

PDFAT2 is a new active peptide with unknown function. It is secreted by adipose tissue and identified by peptidomic analysis. PDFAT2 is significantly down-regulated in patients with PCOS. Dysfunction of granulosa cells in PCOS patients (decreased proliferation, increased apoptosis and hormone disturbance) can lead to abnormal follicle formation in PCOS patients. Our previous study indicated that PDFAT2 can promote the proliferation and inhibit the apoptosis of human granulosa cells. Besides, PDFAT2 can also increase the level of the estrogen. Further research showed that PDFAT2 may be associated with the Wnt/β-catenin signaling pathway. This study is aimed to demonstrate the function of PDFAT2 on the proliferation, cycle and apoptosis of PCOS granulosa cells both in vitro and in vivo. Furthermore, using pull down and other assays, we intend to reveal the molecular mechanism of PDFAT2 in protecting against PCOS. This study may provide a new way for the prevention and treatment of PCOS.

PDFAT2是我们通过多肽组学方法获得的、PCOS脂肪组织分泌的一条功能未知的活性肽，其在PCOS中显著低表达。PCOS患者中颗粒细胞的功能障碍（增殖降低、凋亡增加及分泌的激素紊乱等）可导致PCOS患者异常卵泡的形成。前期实验发现，PDFAT2能够促进人颗粒细胞的增殖，抑制其凋亡，增加雌激素合成。进一步研究发现PDFAT2作用可能与Wnt/β-catenin信号通路的抑制有关。因此本研究拟通过细胞与动物实验，系统论证PDFAT2对PCOS颗粒细胞增殖、周期和凋亡的影响，通过Pull-down等一系列实验，深入阐明PDFAT2通过Wnt/β-catenin通路改善PCOS的分子机制。本研究有望为PCOS的防治提供新思路。

多囊卵巢综合征在育龄妇女中发病率达5%-10%，且有逐年升高趋势，是导致育龄期妇女不孕最常见原因。进一步探讨其发病机制，寻找新的治疗手段已成为该领域亟需解决的重大问题。多肽药物具有毒性低、特异性强、经济成本低等优点，可能成为疾病治疗的最佳选择。我们从脂肪成功筛选获得了一条内源性多肽PDFAT2，并探索了PDFAT2对颗粒细胞增殖、凋亡的影响。收集3例PCOS患者和3例正常对照行试管婴儿取卵日所得卵泡液，PCOS患者血清和卵泡液中PDFAT2浓度显著低于正常对照组。化学合成PDFAT2，加入商品化的颗粒细胞，结果显示，PDFAT2可显著促进颗粒细胞的增殖(图1B)、并抑制凋亡.皮下注射PDFAT2后，高剂量的原始卵泡(P)百分比和窦卵泡百分比与PCOS组都有显著性差异，当大鼠随后接受不同剂量PDFAT2治疗时，黄体百分比与PCOS组均有显著性差异；PDFAT2有改善PCOS卵巢功能障碍方面的作用；LC-MS/MS检测的雄烯二酮、睾酮以及17α-羟孕酮均与HOMA-IR成正相关。