Expression And Significance Of Vitamin D Metabolism Gene CYP24A1 Gene In Placenta And Umbilical Cord Tissues Of Patients With Gestational Diabetes

In recent years,gestational diabetes as perinatal research focus,there is a significant increase in the incidence trend,and adverse pregnancy outcomes female children.The pathogenesis of gestational diabetes is still unclear.Studies have shown that adipocytokines,inflammatory cytokines and vitamin D are involved in the pathogenesis of GDM.Under physiological conditions,vitamin D can increase the sensitivity of insulin,stimulate the secretion of islet cells,and reduce insulin resistance.CYP24A1,as the representative gene encoding the core protein of the vitamin D degradation signal pathway,plays an important role in the vitamin D metabolic system.Therefore,the expression of CYP24A1 in the body of gestational diabetes patients and its role in the pathogenesis need to be further studied.Objectives: Gestational diabetes by measuring the vitamin D-related gene CYP24A1 mRNA in the placenta and umbilical cord tissue relative expression(GDM)and normal pregnancy group(the NGT)the amount of methylation levels and,to investigate the expression and significance of CYP24A1 in patients with gestational diabetes.Methods: A total of 82 singleton pregnant women in the third trimester who underwent cesarean section in HEBEI GENERAL HOSPITAL were selected and divided into GDM group(40 cases)and NGT group(42 cases)according to the OGTT results of 24-28 weeks gestation.The maternal venous blood was collected before the operation.Umbilical cord blood,placental tissue and umbilical cord tissue were collected after delivery of the middle-aged fetus.Plasma vitamin D levels were measured by electrochemical luminescence,the relative expressions of CYP24A1 mRNA and the levels of methylation in placental tissues and umbilical cord tissues were measured by RT-PCR and MSP.Results: 1 Maternal peripheral blood(14.19±4.46 vs.19.52±7.95,P<0.01)and cord blood(15.58±6.26 vs.19.95±9.14,P=0.014)plasma vitamin D levels in the GDM group were significantly lower than those in the NGT group.2 The expression level of CYP24A1 mRNA in placental tissues(2.72±1.23 vs.1.61±0.66,P=0.026)and umbilical cord tissues(1.78±0.60 vs.0.84±0.37,P=0.001)in the people with GDM were obviously higher than those in NGT groups.3 Placental tissue CYP24A1 gene methylation rate(70.59%),umbilical cord tissue methylation rate(88.89%)in GDM group,placental tissue CYP24A1 gene methylation rate(70.91%),umbilical cord tissue methylation rate(88.24%).χ2 test showed that there were no significant differences(P=1.000).4 GDM group maternal peripheral blood plasma vitamin D level was positively correlated with cord blood plasma vitamin D level(r=0.768,P<0.01),GDM group maternal peripheral blood plasma vitamin D level was correlated with placental tissue CYP24A1 mRNA(r=-0.863,P< 0.01)and umbilical cord tissue CYP24A1 mRNA(r= - 0.889,P<0.01)are all negatively correlated.Conclusions: 1 Maternal serum vitamin D levels in the GDM group were significantly lower than those in the NGT group,and maternal serum vitamin D levels were positively correlated with umbilical cord serum vitamin D levels,suggesting that the maternal serum vitamin D level may affect the fetal cord blood vitamin D level through the placental barrier.2 Placenta and umbilical cord tissue expression of CYP24A1 gene mRNA GDM group were significantly higher than the normal pregnancy group,when the estimated gestational diabetes,placenta and umbilical cord tissue CYP24A1 gene expression and reduced levels of vitamin D-related.3 There is no difference between the positive rate of CYP24A1 gene methylation in placental tissue or umbilical cord tissue and normal pregnancy group.It is speculated that the activity of CYP24A1 gene affecting vitamin D level has nothing to do with the level of methylation of this gene.