Evaluation of the efficacy of two doses of vitamin D supplementation on glycemic, lipidemic and oxidative stress biomarkers during pregnancy: a randomized clinical trial

Abstract

Background Vitamin D deficiency during pregnancy is common and is likely to be associated with metabolic complications in the mother. The aim of this study was to assess the efficacy of two doses of vitamin D supplementation during pregnancy on maternal and cord blood vitamin D status and metabolic and oxidative stress biomarkers. Methods The eligible pregnant women (n = 84) invited to participate in the study and randomly allocated to one of the two supplementation groups (1000 IU/d vitamin D and 2000 IU/d). Biochemical assessments of mothers including serum concentrations of 25(OH)D, calcium, phosphate, iPTH, fasting serum sugar (FBS), insulin, triglyceride, total cholesterol, LDL-C, HDL-C, malondialdehyde (MDA) and total antioxidant capacity (TAC) were done at the beginning and 34 weeks of gestation. Cord blood serum concentrations of 25(OH)D, iPTH, MDA and TAC were assessed at delivery as well. To determine the effects of vitamin D supplementation on metabolic markers 1-factor repeated-measures analysis of variance (ANOVA) was used. Between groups comparisons was done by using Independent-samples Student’s t-test or Mann-Whitney test. P < 0.05 was considered as significant. Results Supplementation with 1000 IU/d and 2000 IU/d vitamin D resulted in significant changes in vitamin D status over pregnancy (24.01 ± 21.7, P < 0.001 in 1000 IU/d group and 46.7 ± 30.6 nmol/L, P < 0.001 in 2000 IU/d group). Daily intake of 2000 compared with 1000 IU/d tended to increase the serum concentration of HDL-C (10 ± 8.37, P < 0.001 in 1000 IU/d group and 9.52 ± 11.39 mg/dL, P < 0.001 in 2000 IU/d group). A significant decrement in serum concentration of iPTH observed in both groups (− 4.18 ± 7.5, P = 0.002 in 1000 IU/d group and − 8.36 ± 14.17, P = 0.002 in 2000 IU/d group). Conclusions Supplementation with 2000 IU/d vitamin D as compared with 1000 IU/d, is more effective in promoting vitamin D status and HDL-C serum concentration and in decreasing iPTH over pregnancy. Trial registration This trial is registered at clinicaltrials.gov (NCT03308487). Registered 12 October 2017 ‘retrospectively registered’.

The effect of vitamin D supplementation on oxidative stress and inflammatory biomarkers in pregnant women: a systematic review and meta-analysis of clinical trials

“…Of 17 RCTs, one study had measured circulating 25(OH)D concentration just at the baseline and in the cord blood [ 30 ]. Besides, in two studies the report of 25(OH)D concentration had been duplicated by the same author [ 23 ]. Therefore, the data of one of them was included in the meta-analysis.…”

“…A total of 6 RCTs examined the effects of vitamin D supplementation on TAC [ 10 – 12 , 23 , 26 , 29 ]. The heterogeneity was significant (I 2 = 96.6%, p < 0.001).…”

“…To evaluate the effect of vitamin D supplementation on the concentration of MDA, six studies [ 10 – 12 , 23 , 26 ] were included in meta-analysis. The observed heterogeneity was severe ( p = 0.001, I 2 = 74.71%).…”

Markers of Oxidative Stress in Obstetrics and Gynaecology—A Systematic Literature Review

“…The rest of the markers were researched in either one or two studies: 8-isoprostane ( n = 1), 8-OHdG ( n = 2), total peroxide ( n = 1), nitrotyrosine ( n = 1), 8-iso-prostaglandin F2α ( n = 2), 8-epiprostaglandin F2-α ( n = 1), prostaglandin F2α ( n = 1), thiol ( n = 1), disulphide ( n = 1), TOS ( n = 1), TAS ( n = 1), DNA damage in blood leukocytes ( n = 1), CAT ( n = 2), γ-glutamyl transferase ( n = 1), hs-CRP ( n = 1), GSH ( n = 1), NO ( n = 1), carbonyl proteins ( n = 1), superoxide anion expressed as reduced nitroblue tetrazolium ( n = 1), aldehyde dehydrogenase ( n = 1), GST ( n = 1), soluble fms-like tyrosine kinase-1 ( n = 1), and placental growth factor ( n = 1) [ 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 ].…”

A bibliometric analysis of global research on vitamin D and reproductive health between 2012 and 2021: Learning from the past, planning for the future

“…The Medical University of South Carolina in the United States had the highest ACI, and the top two productive authors are from this institution ( Tables 1 , 2 ). The research team mainly focused on prenatal vitamin D screening ( 63 ), and the effects of vitamin D supplementation on early life (pregnancy, lactation, and childhood), including glycemic, lipidemic, oxidative stress biomarkers ( 64 ), inflammatory biomarkers ( 65 ), growth factors, immune-mediators ( 66 ), bone mineral density ( 67 ), the vaginal microbiome ( 68 ), preeclampsia ( 69 ) during pregnancy, preterm birth ( 70 ), offspring epigenetic clock ( 71 ), asthma, allergies and recurrent wheeze ( 72 – 75 ). The conclusions of most original studies were derived from RCTs, with high-level evidence and instructive significance.…”