卵泡液中神经营养因子4及卵丘细胞TrkB受体与卵子发育潜能的关系

Relationship between Follicular-fluid Neurotrophin-4,TrkB Receptors in Cumulus Cells and Oocyte Developmental Competence

【目的】探索人卵泡液中神经营养因子4(NT-4)及卵丘颗粒细胞中TrkB受体的表达与卵子发育潜能的关系。【方法】收集2020年5月至2020年11月在中山大学附属第六医院生殖中心,因男方因素行卵胞浆内单精子注射(ICSI)治疗的63例患者的卵泡液和卵丘颗粒细胞,用ELISA检测卵泡液中NT-4水平,实时荧光定量PCR检测卵丘颗粒细胞中TrkB受体两种不同亚型TrkB-fl和TrkB-t1的表达水平,分析与卵子成熟、受精和胚胎发育的关系。【结果】卵泡液中NT-4水平与正常受精数(rs=0.250,P=0.048)、可利用胚胎数(rs=0.320,P=0.011)、优质胚胎数(rs=0.327,P=0.009)和优质囊胚数(rs=0.303,P=0.029)呈正相关。卵丘颗粒细胞中TrkB-t1在高囊胚形成率组(≥60%)和高优质囊胚率组(≥50%)中的表达均较低[0.86(0.60,1.85)vs.2.29(1.09,3.44),P=0.008;0.84(0.64,1.45)vs.1.73(0.96,3.14),P=0.031]。多重线性回归分析结果示优质胚胎数受获卵数(P=0.001)、卵泡液中NT-4水平(P=0.005)和卵丘颗粒细胞TrkB-t1表达水平(P=0.049)影响。【结论】人卵泡液中NT-4水平与ICSI患者卵子发育潜能正相关,其可能在卵子发育过程中发挥着重要作用。卵丘颗粒细胞中TrkB-t1的高表达与卵子发育潜能受损有关。

【Objective】To investigate whether the neurotrophin-4(NT-4)in human follicular fluid(FF)and the ex⁃pression of tropomyosin-related kinase B(TrkB)receptors in cumulus cells(CCs)have any correlation with the develop⁃mental competence of oocytes【.Method】FF and CCs were collected from 63 patients undergoing intracytoplasmic sperm in⁃jection(ICSI)in the Reproductive Medicine Center from May to November 2020.NT-4 level in FF was measured by en⁃zyme-linked immunosorbent assay(ELISA)method.The expression levels of two major TrkB isoforms,the full-length re⁃ceptor(TrkB-fl)and the truncated receptor(TrkB-t1),were quantified in CCs by real-time PCR.The correlation of oo⁃cyte maturation,fertilization and embryo development with NT-4 level in FF,TrkB-fl and TrkB-t1 expression in CCs were analyzed.【Results】NT-4 level in human FF was positively correlated with the number of normally fertilized oocytes(rs=0.250,P=0.048),available embryos(rs=0.320,P=0.011),top-quality embryos(rs=0.327,P=0.009)and top-quali⁃ty blastocysts(rs=0.303,P=0.029).The expression level of TrkB-t1 gene in CCs was negatively associated with a higher blastocyst formation rate(≥60%)and top-quality blastocyst rate(≥50%)[0.86(0.60,1.85)vs.2.29(1.09,3.44),P=0.008;0.84(0.64,1.45)vs.1.73(0.96,3.14),P=0.031].Multiple linear regression analysis showed that the number of top-quality embryos was affected by the number of oocytes retrieved(P=0.001),FF NT-4 level(P=0.005)and the ex⁃pression of TrkB-t1 gene in CCs(P=0.049).【Conclusion】FF NT-4 level was positively associated with oocyte develop⁃mental competence,and it might play an important role in the development of oocytes.Over-expressed TrkB-t1 in CCs might be related to compromised oocyte developmental potential.