Study On The Prediction Of Intrafollicular SRAGE On Ovarian Reserve In Women Of Childbearing Age And The Protective Effect On The PCOS

Background Advanced glycation end products(AGEs) are a heterogeneous group of non-enzymatically modified proteins. Obesity, ageing, hyperglycemia, oxidative stress and insulin resistance accelerate the generation of AGEs. The receptor of AGEs(RAGE) come from the immunoglobulin superfamily, and then up-regulation and accumulation of AGEs, which lead to cellular dysfunction and have been implicated in many pathological processes and diseases.sRAGE lacks the cytosolic and transmembrane domains of RAGE and thus acts as a decoy that prevents the adverse intracellular effects of the AGE-RAGE axis. s RAGE consequently serves not only as a biological marker that reflects pathological changes within the body but also as a protective factor that delays the occurrence of diabetes and atherosclerosis.The study of AGE-RAGE on ovarian function reduction in women has reached a consensus. Its promotion effect on the generation and development of PCOS has also become a research hotspot. s RAGE can also be used as a marker of an acceptable development environment and reproductive potential. But some scholars hold on the opposite opinion. Romero et al believed that increased amniotic fluid concentrations of s RAGE were positively associated with inflammation in patients with preterm labour. But Rzepka et al observed a negative trend for s RAGE and CRP in plasma and they conducted that high s RAGE concentrations could avoid premature labor.s RAGE is closely related to inflammatory factors, insulin resistance and ovarian reserve, while the inflammatory response, insulin resistance and diminished ovary reserve are clinical and pathological characteristics of PCOS. It is unclear if s RAGE has a protective effect on the occurrence and development of PCOS.ObjectiveTo study the prediction of sRAGE levels in follicular fluid on ovarian reserve in patients with IVF-ET. To explore the relationships between the s RAGE and the outcome parameters following IVF-ET in patients with PCOS and investigate the protective effect of s RAGE in PCOS development regarding inflammation. Materials and methodsThe subjects in this study were recruited from patients who underwent in vitro fertilization-embryo transfer(IVF-ET) in our reproductive center. The first study included the control and PCOS groups. The control group comprised 35 patients with infertility caused by tubal factors. The PCOS group comprised 39 patients with PCOS and the second study included 10 patients with PCOS.The fluid from the first large aspirated follicle without blood was subjected to enzyme-linked immunosorbent assay(ELISA) to quantify s RAGE, tumour necrosis factor(TNF-α), interleukelin-6(IL-6), and C-reactive protein(CRP) protein levels. Collection and cultivation of granulosa cells, and s RAGE was added at a concentration of 0μg/ml, 0.6μg/ml, 0.9μg/ml, or 1.2μg/ml. After another 24 and 48 h, the granulosa cells of each group were divided into two parts equally. The m RNA of TNF-α, IL-6, CRP were detected by RT-PCR and the protein of TNF-α, IL-6, CRP, RAGE, activated extracellular signal-regulated kinase(p-ERK), and activator protein 1(AP-1)were detected by Western blot.Results1. There is a inverse relationship between follicular fluid sRAGE protein levels and the total dose in international units of Gn used per cycle that was independent of age, BMI, or day 3 FSH(r=-0.328,P=0.041);After adjusting for age, BMI, day 3 FSH, and the dose of Gn used, follicular fluid s RAGE protein levels predicted the total number of oocytes retrieved(r=0.488, P=0.005)。Women who successfully conceived after IVF transplantation had significantly higher s RAGE levels than women who failed to conceive. After adjusting for age, BMI, day 3 FSH, and the dose of Gn used, follicular fluid s RAGE protein levels predicted the pregnancy outcome(Odds ratio =1.014, P=0.039).2. The follicular fluid s RAGE concentration was significantly lower in the PCOS group than in the controls. Follicular fluid s RAGE protein levels in PCOS patients were negatively related to the total dose of Gn international units used per cycle after adjusting for age, BMI, day 3 FSH.3. TNF-α, IL-6, and CRP levels in the follicular fluid were measured with ELISA. VEGF, TNF-α, IL-6 and CRP concentrations in the follicular fluid were higher in the PCOS group than in the controls. The follicular fluid s RAGE protein levels were significantly inversely correlated with TNF-α, IL-6 and CRP( TNF- α,r=-0.450,P=0.004;IL-6,r=-0.455,P=0.004;CRP,r=-0.375, P=0.019). The m RNA of TNF-α, IL-6, CRP m RNA and and the protein of TNF-α, IL-6, CRP, RAGE, p-ERK, and AP-1 levels were both lower in granulosa cells treated with s RAGE compared to untreated granulosa cells, and the effects of s RAGE on expression of TNF-α, IL-6, CRP, RAGE, p-ERK, and AP-1were dose-dependent.ConclusionsRAGE may influence the condition of the reproductive environment and hence reproductive potential and may therefore play a protective role in PCOS occurrence and progression by reducing the expression of inflamation. Targeting AGEs-RAGE signaling represents a potential therapeutic option for the treatment of diminished ovarian reserve and PCOS.