The Study Of The Anti-inflammation Role Of Adiponectin During Pregnancy

Objective: CpG oligodeoxynucleotides(ODNs)induce immunological changes and increased embryo loss rate in non-obese diabetic(NOD)mice but not in wild-type(WT)mice,and little is known about the mechanism.Through a CpG ODN induced high embryo loss rate mouse model,this study aimed to determine the role of adiponectin in CpG ODN-induced pregnancy failure,the signal pathway through witch CpG ODN influence the expression of adiponectin,how CpG ODN effected the founction of trophoblast and whether the anti-inflammatory function of adiponectin could rescue the damage of CpG ODN or not.To provide a better understand of the role of metabolism in the infectious disease of pregnancy.Methods: Established WT×C57BL/6 and NOD×C57BL/6 mating combinations.The point at witch the vaginal plug was detected was designed as gestational day 0.5(E0.5).ODN 1826 control and ODN 1826 were intraperitoneally(IP)injected to WT and NOD mice(each group of mice was randomly divided into 2 groups)on E6.5.On E10.5,mice were sacrificed by cervical dislocation and embryo loss rates were calculated.QRT-PCR,western blot,immunofluorescence and immunohistochemistry assaies was performed to investigate the expression level and pattern of adiponectin in placenta.Stimulated BeWo cells with forskolin(FSK)to build a syncytiotrophoblast cell model in vitro,and used ODN 2216,ODN 2216 control,ODN 2006,ODN 2006 control,ODN 2395 and ODN 2395 control to stimulate fused BeWo cells to determine the type of CpG ODN which could down-regulated the expression of adiponectin.Then the specific inhibitors SP600125 and PD98059 were used to block the c-Jun N-terminal protein kinase(JNK)and mitogen-activated protein kinase(MEK)signaling pathways,respectively,to investigate the signal pathway between adiponectin expression and CpG ODN in syncytiotrophoblast.To study the influence of CpG ODN on the syncytialization and secretion function of syncytiotrophoblast,QRT PCR,Western blot,gene knockdown and overexpression and immunofluorescence experimental methods were used to confirm the influence of adiponectin on the damaged syncytialization and secretion of fused BeWo cells caused by CpG ODN.HTR-8 and JAR cells were chosen as cytotrophoblast cell models.Transwell and gelatin zymography assaies were chosen to study the effect and mechanism of adiponectin on the migration function of CpG ODN infected cytotrophoblast cells.Results: CpG ODNs led to increased embryo loss rate and down-regulated adiponectin expression in placenta in NOD mice but not in WT mice.The immunohistochemistry,bicolor immunofluorescence assaies performed with mice placenta and immunestochemistry assay performed with human villus and decidual tissues showed that adiponectin expressed in the villus syncytiotrophoblast and decidual glands.BeWo cells can be fused by FSK stimulation,and adiponectin expression increased with increasing degree of syncytialization.Then stimulated fused BeWo cells with CpG ODNs(ODN 2216,ODN 2006 and ODN 2395)and their respective controls,and western blot results showed that ODN 2006 down-regulated the expression of adiponectin in fused BeWo cells.After added the specific inhibitors of JNK and MEK signal pathwaies,western blot and immunofluorescence assaies results showed ODN 2006 down-regulated adiponectin expression through JNK signal pathway.ODN 2006 impaired the syncytialization and secretion of human syncytiotrophoblast cells(ODN 2006 down-regulated Leptin,syncytin-2 and ?-HCG mRNA expression in fused BeWo cells).QRT-PCR and immunofluorescence experiments results showed that adiponectin could not rescue the damage of ODN 2006 on syncytiotrophoblast functions.Transwell and gelatin zymography results showed that ODN 2006 damage the migration of HTR-8 and JAR cells through destroying the activation of MMP-2,but it was successfully rescued by adiponectin treatment.Conclusions: CpG ODNs decreased placental adiponectin expression in NOD mice,impaired human trophoblast function,and was associated with increased embryo loss.Adiponectin may therefore play an important protective role in the prevention of bacteria-induced pregnancy failure.