睾酮缺乏除影响生殖系统健康外，还会造成男性机体代谢异常和认知功能下降，严重影响男性的身体健康和生活质量。中老年男性睾酮下降的主要原因是睾酮分泌细胞（Leydig细胞）的老化，但机理未明。前期结果显示，老化Leydig细胞内炎症相关信号通路异常活跃，且miR-299a-5p表达下调。进一步研究表明，沉默miR-299a-5p的表达可抑制Leydig细胞雄激素的产生并促进其衰老分泌相关表型（SASP）因子的合成。由于miR-299a-5p靶向NF-κB1，因此，本项目提出炎症因子通过调控miR-299a-5p的表达介导Leydig细胞衰老的假设，并拟采用免疫共沉淀、CHIP-Seq、单细胞测序及生物信息学等方法，系统阐明细胞外炎症微环境诱发睾丸Leydig细胞衰老的分子机制。本研究将为揭示男性性腺组织衰老的表观遗传调控及性腺机能低下疾病的诊断治疗提供重要的理论基础和实验依据。

In addition to affecting the health of the reproductive system, testosterone deficiency can also cause metabolic abnormalities and cognitive decline in the male body, which seriously affects the physical health and quality of life of men. The main cause of testosterone decline in middle-aged and elderly men is the aging of testosterone-producing cells (Leydig cells), but the mechanism is unknown. Previous results showed that the inflammation-related signaling pathway in aging Leydig cells was abnormally active and the expression of miR-299a-5p was down-regulated. Further studies showed that silencing of miR-299a-5p expression inhibits the production of testosterone in Leydig cells and promotes the synthesis of senescence-associated secretory phenotype (SASP) factor. Based on the observation that miR-299a-5p targets NF-κB1, we propose the hypothesis that inflammatory factors mediate the aging of Leydig cells by regulating the expression of miR-299a-5p. We will use co-immunoprecipitation, CHIP-Seq, single-cell sequencing and bio-informatics and other methods to systematically elucidate the molecular mechanism by which extracellular inflammatory microenvironment inducesLeydig cell senescence in the testis. This study will provide an important theoretical basis and experimental evidences for revealing the epigenetic regulation of male gonad aging and the diagnosis and treatment of hypogonadism.