Effects Of Oxidative Stress And Fatty Acid Groups On Placental Iron Transfer During Late Bedtime Last Trimester

Objective:To study the process of iron death induced by placental oxidative stress mediated by inflammatory factors and fatty acid groups,explore whether bedtime has an effect on the iron transfer function of the placenta in pregnant women,and study the pathophysiological basis of its occurrence and development,which will realize the early detection and improvement of sleep hygiene during pregnancy,strengthen intrauterine iron horizontal transfer,and provide new scientific basis and theoretical guidance for the protection of maternal and infant physical and mental health.Methods:A total of 123pregnant women were admitted to the Second Affiliated Hospital of Xiamen Medical College from August 2021 to December 2022.Their general demographic information and clinical data were collected,and the current bedtime was recorded.Pregnant women were 18-41 years old,with an average age of（29.84±3.98）years.The gestational week in the third trimester of pregnancy was 35 weeks+1 day-36 weeks+6 days,and the gestational week at birth was 37weeks+1 day-41 weeks+60 days.The first question in the Pittsburgh sleep quality index（PSQI）was divided into a bedtime early group（going to bed before 11 pm,n=42）and a bedtime late group（going to bed after 11 pm,n=81）.The edinburgh postnatal depression scale（EPDS）was used to quantify the degree of depression in prenatal pregnant women,and the total scores of PSQI and EPDS were calculated.Peripheral blood,placental tissue,and umbilical artery blood were collected during childbirth.The level of interleukin-6（IL-6）in peripheral blood was measured.The levels of ferritin and transferrin（Tf）in serum,placenta,and umbilical artery were measured.The levels of glutathione peroxidase 4（GPX4）,malondialdehyde（MDA）,and glutathione（GSH）in the placenta were measured.The levels of unsaturated fatty acids（14 unsaturated fatty acids（SFA）and 15 unsaturated fatty acids（UFA））in plasma and umbilical artery serum were measured.The differences in all biomarkers between the two groups were analyzed.The correlation between bedtime and umbilical artery serum ferritin and Tf levels,peripheral blood biomarkers（IL-6,ferritin,Tf,fatty acid group）,placental biomarkers（ferritin,Tf,GPX4,MDA,GSH）,and umbilical artery serum fatty acid groups was analyzed.We analyzed whether the levels of independent fatty acids in peripheral blood and umbilical artery in the bedtime late group have a regulatory role in the process of bedtime affecting serum ferritin and Tf levels in the umbilical artery.Factor analysis and hierarchical stepwise linear regression analysis were performed on the levels of ferritin and Tf in peripheral blood and umbilical artery serum fatty acid groups in the two groups.Results:（1）The levels of umbilical artery serum ferritin,peripheral blood Tf,placental MDA and GSH in bedtime early group were higher than those in bedtime late group（Pumbilical artery serum ferritin=0.014,Pperipheral blood Tf=0.026,PMDA=0.010,PGSH=0.045）.Placental ferritin and Tf levels in the bedtime early group were higher than umbilical artery serum levels>peripheral blood levels(P_ferritin=0.006,P_Tf<0.001),Tf level of placenta>peripheral blood>serum level of umbilical artery in the bedtime late group（P<0.001）,the levels of other biomarkers were not different between the two groups（P>0.05）.（2）There was a positive correlation between bedtime and placental MDA and GSH levels in the bedtime early group(P_MDA=0.018,P_GSH=0.031).In the bedtime late group,bedtime was negatively correlated with the levels of umbilical artery serum ferritin and Tf and placental Tf(P_umbilicalartery serum ferritin=0.015,Pumbilical artery serum Tf=0.048,Pplacental Tf=0.011).The levels of placental MDA and GSH in the bedtime late group were negatively correlated with the levels of umbilical artery serum Tf(P_MDA=0.012,P_GSH=0.021),but there was no correlation between the bedtime and the levels of umbilical artery serum ferritin and Tf with the levels of other biological markers between the two groups（P>0.05）.（3）Hierarchical stepwise linear regression analysis showed that bedtime was positively correlated with placental MDA and GSH levels in the bedtime early group(P_MDA=0.041,P_GSH=0.039).The bedtime of the bedtime late group was negatively correlated with the levels of ferritin and Tf in the umbilical artery(P_ferritin=0.015,P_{umbilical artery Tf}=0.048),and the level of MDA in the placenta of the bedtime late group was negatively correlated with the levels of Tf in the umbilical artery（P=0.012）.It was found that peripheral C11:0 and C22:1 negatively regulated the effect of bedtime on the Tf level of the placenta(P_C11:0=0.006,P_C22:1=0.005).（4）Factor analysis and hierarchical stepwise linear regression analysis found that in the bedtime early group:Peripheral SFA common factors 2（C10:0,C23:0,C20:0,C11:0,C24:0,and C12:0）were negatively correlated with placental ferritin and Tf levels(P_ferritin=0.004,P_Tf=0.002).Serum SFA common factor 4（C14:0 and C13:0）was positively correlated with placental ferritin and Tf levels(P_ferritin=0.023,P_Tf=0.019),and common factor 2（C11:0,C23:0,C18:0,C10:0,C10:0,and C16:0）and common factor 3（C12:0,C15:0,and C22:0）were negatively correlated with placental ferritin levels(P_{common factor 2}=0.031,P_{common factor 3}=0.033).Peripheral UFA common factors 1（C20:1,C18:1,C20:2（n-6）,C18:2（n-6）,C20:5（n-3）,and C15:1）and common factors 3（C16:1,C18:3（n-6）,and C24:1）were negatively correlated with placental ferritin levels(P_{common factor 1}=0.008,P_{common factor 3}=0.036),and common factor 4（C17:1 and C18:3（n-3））was positively correlated with placental ferritin levels（P=0.006）.Serum UFA common factor 3（C16:1 and C17:1）was positively correlated with placental ferritin levels（P=0.002）.Conclusion（1）Bedtime late in the third trimester of pregnancy can aggravate the abnormal occurrence of placental iron transfer through placental oxidative stress rather than placental iron death.Therefore,bedtime early can help prevent and strengthen the ability of pregnant women to transfer intrauterine iron,reducing the likelihood of maternal and infant complications.（2）In addition to the protective effect of monounsaturated fatty acids,the combined effect of high levels of fatty acids is a risk factor for placental iron transfer,regardless of whether you go to bed early or late.Therefore,pregnant women should not only improve sleep hygiene,but also pay attention to the balance of various fatty acid content in their daily dietary intake,and try to diversify their diet,not just focus on a single diet.