[A survey on the current situation of serum vitamin A and vitamin D levels among children aged 2-<7 years of 20 cities in China].

Objective: To investigate serum vitamin A and vitamin D status in children aged 2-<7 years in 20 cities in China. Methods: A cross-sectional study was conducted. A total of 2 924 healthy children aged 2-<7 years were recruited from September 2018 to September 2019 from 20 cities in China, categorized by age groups of 2-<3 years, 3-<5 years, and 5-<7 years. The demographic and economic characteristics and health-related information of the enrolled children were investigated. Body weight and height were measured by professional staff members. The serum vitamin A and vitamin D levels were detected by high-performance liquid chromatography-tandem mass spectrometry. Chi-square test and Logistic regression were applied to analyze the association between vitamin A and vitamin D deficiency and insufficiency as well as their underlying impact factors. Results: The age of the 2 924 enrolled children was 4.33 (3.42, 5.17) years. There were 1 726 males (59.03%) and 1 198 females (40.97%). The prevalences of vitamin A and vitamin D deficiency in enrolled children were 2.19% (64/2 924) and 3.52% (103/2 924), respectively, and the insufficiency rates were 29.27% (856/2 924) and 22.20% (649/2 924), respectively. Children with both vitamin A and vitamin D deficiencies or insufficiencies were found in 10.50% (307/2 924) of cases. Both vitamin A (χ2=7.91 and 8.06, both P=0.005) and vitamin D (χ2=71.35 and 115.10, both P<0.001) insufficiency rates were higher in children aged 3-<5 and 5-<7 years than those in children aged 2-<3 years. Vitamin A and vitamin D supplementation in the last 3 months was a protective factor for vitamin A and D deficiency and insufficiency, respectively (OR=0.68 and 0.22, 95%CI 0.49-0.95 and 0.13-0.40, both P<0.05). The rates of vitamin A and D insufficiency was higher in children with annual household incomes <60 000 RMB than in those with annual household incomes ≥60 000 RMB (χ2=34.11 and 10.43, both P<0.01). Northwest and Southwest had the highest rates of vitamin A and vitamin D insufficiency in children aged 2-<7 yeas, respectively (χ2=93.22 and 202.54, both P<0.001). Conclusions: Among 20 cities in China, children aged 2-<7 years experience high rates of vitamin A and vitamin D insufficiency, which are affected by age, family economic level, vitamin A and vitamin D supplementation, and regional economic level. The current results suggest that high level of attention should be paid to vitamin A and vitamin D nutritional status of preschool children.

Folic acid attenuates dexamethasone-induced placental growth restriction.

OBJECTIVE: Intrauterine glucocorticoid (GC) exposure is associated with disturbances in feto-placental growth. This study aimed to investigate whether folic acid supplementation can prevent dexamethasone (Dex)-induced feto-placental growth restriction. MATERIALS AND METHODS: Female C57BL/6J mice were subject to four different treatments, respectively: normal drinking water plus saline injection (NN), normal drinking water plus Dex injection (ND), drinking water supplemented with folic acid plus saline injection (FN), and drinking water supplemented with folic acid plus Dex injection (FD). Folic acid (100 µg/L) was administrated since 2 weeks before the mating and throughout pregnancy. Dex injection (100 µg/kg•d) was performed from E12.5 to E16.5. The placentas were collected at E17.5. RESULTS: The parameters including placental and fetal weight, the maximum placental diameter, volume of junctional and labyrinthine zones, and vascular density in the ND group were significantly smaller compared to the NN group. Except the maximum placental diameter, each of the above parameters in the FD group was significantly larger compared to the ND group. The levels of glucocorticoid receptor (GR) protein, and endothelial growth factor A, C (VEGFA, VEGFC) and placental growth factor (PIGF) mRNAs were significantly lower in the ND group compared to NN group. The VEGFA and PIGF mRNA level in the FD group was significantly higher than that in the ND group, as well as VEGFA and VEGFC protein level. CONCLUSIONS: Folic acid may attenuate Dex-induced restriction on placental growth by elevating the expression of VEGFA and PIGF, and further raising vascular density.