The Study Of Intrafollicular Melatonin Levels And Its Effect And Mechanism In Ovarian Hyperstimulation Syndrome(OHSS)

Background:Ovarian hyperstimulation syndrome（OHSS）is one of the most severe complications after ovarian stimulation.For recent years,people have done a lot of research on the relationship between OHSS and oxidative stress.Melatonin（N-acetyl-5-methoxytryptamine）is detectable in virtually every component of the human body including follicular fluid（FF）.Melatonin and its metabolites are broad-spectrum antioxidants and free radical scavengers of plasma.SESN2 plays an important role in anti-oxidant and anti-ROS fields.We suppose that there are close relationship among OHSS,SESN2 and melatonin.The first chapiter of this research is to evaluate the possible relationship between FF melatonin levels and IVF outcomes in women undergoing assisted reproductive treatment grouped based on their AFC;The second chapiter of this research is to compare FF melatonin levels between OHSS patients and non-OHSS women undergoing IVF-ET and to evaluate the possible relationship between FF melatonin levels and IVF outcomes in OHSS women and non-OHSS women;In the third chapiter,we aim to explore the SESN2levels in OHSS patients and the role and mechanism of melation plays via SESN2 in OHSS patients.Methods:1.Sixty-three females（20 to 40 years old）scheduled for IVF were divided into three groups based on their AFC.We determined FF melatonin levels in group A（AFC≦6,n=21）,group B（7≦AFC≦14,n=22）,group C（AFC≧15,n=20）on oocyte retrieval day;We evaluated the possible relationship between FF melatonin levels and IVF outcomes;2.We also determined FF melatonin levels in twenty OHSS women and twenty-three non-OHSS women on oocyte retrieval day and evaluated its relationship with IVF outcomes and OHSS predictive indices;3.We collected the granulosa cells of OHSS patients and built the OHSS oxidative stress models by incubating KGN with H₂O₂ and HUVEC with angiotensin II.SESN2 and other related molecules were studied by q PCR and Western blot.Small interfering RNA knocking down was used to change the expression of SESN2.Results:1.Patients in group C（AFC≧15）had significantly higher melatonin levels as compared to patients in groups A（AFC≦6）and B（7≦AFC≦14）（P<0.01）.The FF melatonin levels were significantly correlated with ovarian reserve indices and IVF outcomes（P<0.01）;2.OHSS patients had significantly higher FF melatonin levels as compared to non-OHSS women（P<0.001）.The FF melatonin levels were significantly positively correlated with AFC,serum AMH levels,serum E₂ levels on h CG day,number of retrieved oocytes（P<0.01）and negatively correlated with age（P<0.05）;3.The expression of SESN2 levels are elevated in the granulosa cells of OHSS patients.The OHSS oxidantive stress models showed that SESN2 is involved in the oxidative stress of OHSS.Melatonin can partly reverse this process.Conclusions:1.FF melatonin levels are elevated in women with AFC≧15 than in women with AFC<15 and are positively related to IVF outcomes;2.FF melatonin levels were significantly higher in OHSS patients than in non-OHSS group and can be served as an indicator of OHSS;FF melatonin levels may influence IVF outcomes;3.SESN2 is elevated in granulosa cells of OHSS patients and is involved in the oxidative stress of OHSS by regulating the apoptosis of granulosa cells and endothelium cells.Meanwhile,melatonin can partly reverse this process.