基于精浆代谢调控的弱精子症病理机制研究

Asthenozoospermia (AS) is a common cause of human male infertility. The diagnosis and therapy of the AS are problems in andrology, for its limited diagnostic parameters and unknown etiology. Semen is the most important sample for the clinic diagnosis of male infertility. Seminal Plasma (SP) plays various roles in the sperm functions, especially in sperm viability, motility and capacitation. So it is very essential for the AS pathogenesis to study the pathways or targets between the sperm and metabolites in SP. In this project, we use LC-TOF/MS and GC-MS to study the SP metabolomics of healthy donors and AS patients. The arachidonic acid (AA) metabolic network of SP is found to be changed significantly in AS patients compared with healthy donors after the metabolomic analysis. Then, three different rat asthenospermia models and in vitro human sperm experiments are carried out separately to dynamically evaluate the correlations among the AA metabolic network / its major metabolites, AS pathogenesis progress, and sperm MAPKs pathway which is closely related to the sperm quality and can be activated by AA in the previous study. It is presumed that abnormal AA metabolic network causes poor human sperm quality via MAPKs pathway in the AS pathogenesis. The results of the project will be meaningful in expanding the metabolomic research, explaining the AS pathogenesis, and finding new diagnostic markers and medical targets.

弱精子症（AS）占男性不育致病因素的50%，因机制不明，其诊断和治疗是男科一大难题。精浆是精子赖以在存的微环境，研究精浆代谢物与精子活力间的作用，可为AS诊断和病理提供理论依据。本课题采用LC-TOF/MS、GC-MS等技术，首次进行健康男性、AS患者精浆代谢组学研究，发现病理精浆中糖、花生四烯酸（AA）等代谢网络异常变化。因精子MAPKs通路与精子活力、AA皆密切相关，我们通过临床弱精子症代谢解析、不同诱因（雷公藤多甙、奥硝唑、氢化可的松）所致AS大鼠模型和体外人精子实验，从代谢、细胞、分子多个技术层面，动态研究AA代谢网络及其主要代谢物与AS病理进程、精子MAPKs通路间的关系和作用机制。首次提出并证明：精浆中异常的AA代谢网络通过MAPKs通路来影响精子活力，可能是AS重要的病理机制。该课题的开展，对拓展代谢组学研究，以新的视角阐述AS病理发生、发现新的诊断标志物和治疗靶点有重要意义

弱精子症占男性不育致病因素的50%。因病情隐匿、机制不明、诊断指标单一，弱精子症的诊疗是男科的一大难题。精浆是精子赖以生存的微环境，不仅为精子提供能量和营养，还在精子活力、运动性、获能等功能中具有重要作用。因此深入分析精浆内代谢物质的变化，研究精浆与精子间作用的通路或靶点，可对精子病理机制及药物治疗提供理论依据。.本课题研究分为三部分，第一部分建立了基于GC-MS和LC-MS/MS的健康男性和弱精子症患者的精浆代谢组学研究的分析方法；然后解析与确认了与弱精子症病理密切相关的小分子代谢物及其代谢通路，其中GC/MS在代谢组学分析中鉴别了氨基酸，糖类和脂肪酸等内源性物质45个化合物，38个有显著性差异；LC-MS/MS检测出人体内花生四烯酸代谢产物52种，15个有显著性差异。所得结果为通过精浆代谢研究弱精症的病理机制和临床诊断提供了临床实验数据。第二部分试验，分别用雷公藤多苷和奥硝唑诱导形成动物弱精子症病理模型，模拟临床病变并研究弱精子症发生发展与精浆代谢变化的关系，所得的动物弱精症代谢变化结果与临床数据趋势相似，进一步证实了精浆花生四烯酸代谢调控与弱精子症病变的机制密切相关。第三部分是用体外精子细胞实验证明，当精浆中花生四烯酸代谢异常时，它的三个主要代谢通路COX、LOX、CYP450及其代谢产物，可通过激活精子上的 p38 MAPK 而显著降低精子活动力。.本项目基于精浆的代谢调控，结合临床病理与基础研究，链接代谢组-代谢网络-目标代谢产物-细胞信号转导通路，进行自上而下地递进研究。研究的内容和思路有较强的创新性。研究结果证明：精浆中异常的花生四烯酸代谢通路（COX, LOX, CYP450），通过精子p38 MAPK 来影响精子活动力，是弱精子症的病理机制之一。该研究成果对代谢组学研究的拓展和深入，以新的视角阐述弱精子症病理发生机制、发现疾病诊断标志物和新药治疗靶点具有重要意义。