The Pathogenesis Research Of OHSS Treatment And Prevention Using Prednisolone

Ovary hyperstimulation syndrome (OHSS) is the most serious complication in assisted reproduction especially during IVF-ET. The total incidence rate is about 23.3%,0.008%～10% in severe cases, normally below 2%. The main pathophysiolo-gical events of OHSS are the increase in vascular permeability and subsequent loss of fluid into the third space. The main clinical symptoms and signs are ascites, hydrotho-rax, liver and renal failure, oliguria, hypovolaemic shock, thromboembolic episodes, adult respiratory distress syndrome (ARDS), and death. There is presently no cure for OHSS and only preventive measures are available, so it's very necessary to find an effective method to treat and prevent this disease and to investigate the possible etiology of this disease to support the clinical managements.The pathogenesis of OHSS is still unknown. In recent 10 years several contributions have directed our attention on the prominent role of VEGF in the pathological increase of vascular permeability as mainly responsible of this complication. VEGF is the pivotal role in the etiology of OHSS.VEGF and IL-6 are potential mediators in the development of OHSS for the following reasons:they have the vasoactive properties and can increase the permeability of the vessels; they have been indentified in the follicular fluid and their mRNA transcripts and proteins have been detected in granulose-luteal cells; they are increased in serum, peritoneal fluid and/or follicular fluid of women who develop OHSS as compared with controls.Corticosteroid has anti-inflammation function and can inhibit the infectious and non-infectious inflammations through decreasing many cytokines and reducing the vascular permeability, celluar infiltration and exudation. Prednisolone is an active form and can act directly on the target cells and organs. It's a B drugs in FDA and is safe during early pregnancy using.This study will explore the VEGF. IL-6 level and VEGF mRNA expression in ovary tissue of Wistar rat OHSS model with or without prednisolone treatment and the VEGF mRNA expression of human ovary follicular granular cells in patients who undergo IVF-ET treatments. To illustrate the treatment and preventive mechanism of prednisolone in OHSS.Section I Pathogenesis Research of OHSS Using Prednisolone in Wistar RatsObjective:to observe wether the prednisolone has treatment and preventive functions in the OHSS in Wistar rat model. To investigate the treatment and preventive mechanism of prednisolone in OHSS model by testing the VEGF and IL-6 level in blood, abdominal fluid and the VEGF mRNA expression of ovary tissue.Methods:OHSS rat model were induced using Ujioka methods. The criteria of OHSS model are enlargement of ovaries with increasing of abdominal vessel permeability and occurring of abdominal fluid.50 immature female Wistar rats were obtained and 10 rats in each group.20 rats received prednisolone treatment with 0.3mg/d and 0.6mg/d dosage which enrolled in group A and B respectively. The other 30 rats are in Group C, D and E also called OHSS group, PMSG group and control group correspondingly.When the rats were killed, serum and abdominal fluid were collected for VEGF and IL-6 assays. VEGF protein and mRNA expression level was compared among 5 groups in the ovary using immunohistochemistry and real-time RT-PCR.Results:the ovary weight in group A, B and C are statistically higher than that in group E; the weight in group C icreased significantly than that in group B and D. The No. of having abdorminal fluid in group C is significantly higher than that of other 4 groups. The VEGF protein and VEGF mRNA expression in ovary in group A and B are significantly lower than that in group C. The levels of blood VEGF in group A and B are significantly lower than that in group C; the VEGF level in ascites in group A, B and D are significantly higher than that in group C.Section II The Pathogenesis Research of OHSS in Granular Cell Using PrednisoloneOjectives:to investigate the effects of prednisolone to VEGF mRNA expression of human ovary granular cell.Methods:56 patients undergoing IVF-ET in our center from 2009-12 to 2010-1 were enrolled in this study. They were divided into 3 groups:18 patients who had low OHSS possibilities were in group A; 21 patients who had high OHSS factors but not PCOS were in group B; 17 PCOS patients who had high risk of OHSS possibilities were in group C.The follicular fluid were collected during oocyte retrieval and the VEGF and IL-6 level in follicular fluid were detected using Elisa while granular cells were obtained from all follicular fluid and cultured in culture medium. The prednisolone was given to half granular cells which called T(test) group while the other half was prednisolone free which called C(control) group. Media was totally changed the 1st 24 hours(hr) and the prednisolone were given at 48hr and 96hr. Culture media were collected at 120hr and VEGF and IL-6 were measured while the granular cells were collected in trizol and VEGF mRNA expression were tested using real-time RT-PCR.Results:the VEGF level in follicular fluid in group A is significantly higher than that in group B and C. The IL-6 level in follicular fluid in group A and B were statistically lower than that in group C. The VEGF levels in culture media when adding prednisolone in group A, B and C were significantly decreased than that when prednisolone free. The IL-6 level in the culture media when adding prednisolone in group A, B were significantly increased than that when prednisolone free. The VEGF mRNA expression when adding prednisolone is significantly decreased in all 3 groups than that when prednisolone free.Conclusion:The prednisolone can effectively decrease the ovary weight, ascites and VEGF level in blood of OHSS rat model, can effectively inhibit the ovary VEGF mRNA expression of Wistar OHSS model. The prednisolone can decrease the VEGF level and VEGF mRNA expression of granulose cell in vitro.Therefore prednisolone can be used as a treatment and preventive method for the OHSS.