Objective To investigate the effects of folate deficiency on changes in histone H3 lysine 4 (H3K4) mono-methylation (me1)-marked enhancers and the molecular mechanism underpinning the folate deficiency-induced neural tube defects (NTD). Methods Mouse embryonic stem cells (mESCs) were cultured in the folate-free DMEM medium (folate-deficient group) and the DMEM medium containing 4 mg/L folate (normal control group),respectively.Chromatin immunoprecipitation sequencing (ChIP-seq) was performed for H3K4me1. The mouse model of folate-induced NTD was established,and transcriptome sequencing (RNA-seq) was performed for the brain tissue of fetal mice to reveal the differential expression profiles.The results were validated through real-time quantitative polymerase chain reaction (RT-qPCR).The activity of the differential peak regions of H3K4me1 was verified through the luciferase reporter assay. Results The folate content in the mESCs cultured in the folate-free medium reduced compared with that in the normal control group (P=0.008).The H3K4me1-maked enhancers in the mESCs cultured in the folate-free medium induced significant changes in intronic regions,and these changes were concentrated in metabolic and energy metabolism processes (q=9.56×10^-48,P=1.28×10^-47).The differentially expressed genes harboring H3K4me1-marked enhancers in mESCs were mainly enriched in the Wnt signaling pathway (q=0.004,P=0.004 7).ChIP-qPCR results confirmed that H3K4me1 binding decreased in the differential peak regions of the Ldlrap1 gene (P=0.008),Camta1 gene (P=0.002),and Apc2 gene (P=0.012).The H3K4 demethylase inhibitor T-448 effectively reversed the H3K4me1 binding in the differential peak regions of the aforementioned genes (P=0.01).The results of RNA-seq for the brain tissue of NTD fetal mice showed significant enrichment of the differentially expressed genes in the Wnt signaling pathway (P=1.52×10^-5).The enrichment of differential peak regions of H3K4me1-marked enhancers in Apc2,Ldlrap1,and Camta1 genes in the brain tissue also showed significant changes.The differential peak region in Apc2 exhibited transcription factor activity (P=0.020). Conclusion Folate deficiency may affect changes in H3K4me1-marked enhancers to participate in the regulation of neural tube closure genes,thereby inducing the occurrence of NTD.
Neural Tube Defects/genetics* ; Animals ; Mice ; Folic Acid Deficiency/complications* ; Histones/metabolism* ; Folic Acid/metabolism* ; Methylation ; Mouse Embryonic Stem Cells/metabolism* ; Wnt Signaling Pathway ; Lysine/metabolism* ; Chromatin Immunoprecipitation Sequencing

We evaluated the prevalence of vitamin B12 deficiency and associated factors in type 2 diabetes patients using metformin. A total of 799 type 2 diabetes patients using metformin was enrolled. Vitamin B12 and folate levels were quantified by chemiluminescent enzyme immunoassay. Vitamin B12 deficiency was defined as vitamin B12 < or = 300 pg/mL without folate deficiency (folate > 4 ng/mL). The prevalence of vitamin B12 deficiency in metformin-treated type 2 diabetes patients was 9.5% (n = 76), and the mean vitamin B12 level was 662.5 +/- 246.7 pg/mL. Vitamin B12 deficient patients had longer duration of metformin use (P < 0.001) and higher daily metformin dose (P < 0.001) than non-deficient patients. Compared with daily metformin dose of < or = 1,000 mg, the adjusted odds ratio for 1,000-2,000 mg, and > or = 2,000 mg were 2.52 (95% CI, 1.27-4.99, P = 0.008) and 3.80 (95% CI, 1.82-7.92, P < 0.001). Compared with metformin use of < 4 yr, the adjusted odds ratios for 4-10 yr, and > or = 10 yr were 4.65 (95% CI, 2.36-9.16, P < 0.001) and 9.21 (95% CI, 3.38-25.11, P < 0.001), respectively. In conclusion, our study indicates that patients with type 2 diabetes treated with metformin should be screened for vitamin B12 deficiency, especially at higher dosages (> 1,000 mg) and longer durations (> or = 4 yr) of treatment.
Aged ; Area Under Curve ; Diabetes Mellitus, Type 2/complications/diagnosis/*drug therapy ; Female ; Folic Acid/blood ; Humans ; Hypoglycemic Agents/adverse effects/*therapeutic use ; Immunoassay ; Male ; Metformin/adverse effects/*therapeutic use ; Middle Aged ; Odds Ratio ; Patients ; Prevalence ; ROC Curve ; Time Factors ; Vitamin B 12/blood ; Vitamin B 12 Deficiency/diagnosis/epidemiology/*etiology

Brain ; metabolism ; pathology ; Child, Preschool ; Chromatography, High Pressure Liquid ; Diagnosis, Differential ; Folate Receptor 1 ; genetics ; metabolism ; Folic Acid ; blood ; cerebrospinal fluid ; metabolism ; Folic Acid Deficiency ; diagnosis ; drug therapy ; etiology ; Humans ; Infant ; Leucovorin ; therapeutic use ; Malnutrition ; complications ; diagnosis ; Tetrahydrofolates ; cerebrospinal fluid ; metabolism

OBJECTIVEThis study examined the effects of maternal deficiency of folic acid during pregnancy on pulmonary development and protein A (SP-A) expression in newborn rats in order to explore the possible mechanism of lung developmental disorders.

METHODSThirty-six adult Sprague-Dawley female rats were randomly assigned into two groups: control and study (n=18). The study and the control groups were fed with fodder containing folic acid or not respectively. Two weeks later, the female rats in the two groups copulated with normal male rats. Newborn rats were sacrificed at 1, 7 and 14 days after birth (8 pups at each time point). Lung sections were stained with hematoxylin and eosin for histological examination. SP-A expression of protein and mRNA were determined by immunohistochemistry and real-time quantitative RT-PCR, respectively.

RESULTSThe newborn rats from the study group showed damaged lung tissue structures. The mean optical density of type II cells with positive expression of SP-A decreased significantly from 1 to 14 days in newborn rats of the study group compared with the control newborn rats (P<0.05). The real-time quantitative RT-PCR showed that the expression of lung SP-A mRNA also decreased significantly from 1 to 14 days in newborn rats of the study group compared with control newborn rats (P<0.05).

CONCLUSIONSMaternal deficiency of folic acid during pregnancy can decrease the expression of SP-A in lung tissues of newborn rats, which might lead to the disorder of lung development maturation.

Animals ; Animals, Newborn ; Female ; Folic Acid Deficiency ; metabolism ; Immunohistochemistry ; Lung ; embryology ; Male ; Pregnancy ; Pregnancy Complications ; metabolism ; Pulmonary Surfactant-Associated Protein A ; analysis ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction

5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase ; genetics ; Carrier Proteins ; genetics ; Congenital Abnormalities ; etiology ; Folate Receptors, GPI-Anchored ; Folic Acid Deficiency ; complications ; etiology ; Homocysteine ; blood ; Humans ; Membrane Transport Proteins ; genetics ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Receptors, Cell Surface ; genetics

OBJECTIVETo evaluate the possible effects of folate on cervical carcinogenesis and the interaction of folate and human papillomaviruses 16 (HPV16).

METHODSA hospital-based case-control study was conducted. 111 hospitalized cases who were pathologically diagnosed of having cervical cancer and 111 controls identified with hysteromyoma that frequency-matched to cases on age, birth place and residential area. A 60-item food-frequency questionnaire (FFQ) were administered to estimate the consumption of dietary folate. HPV16 DNA in exfoliated cervical cell and serum folate were detected by special PCR and radioimmunoassay respectively.

RESULTSHPV16 infection rate in cases (61.26%) was significantly higher than that in controls (28.83%), with adjusted OR of 4.95(95% CI:2.49-9.83).The levels of dietary folate in cases (5.00 microg/kcal +/- 0.41 microg/kcal) were significantly lower than that in controls (5.14 microg/kcal +/- 0.35 microg/kcal), but the adjusted OR showing no statistical significance. However, serum folate in cases (1.79 ng/ml +/- 1.42 ng/ml) was significantly lower than that in controls(2.59 ng/ml +/- 2.81 ng/ml),and there were significantly increasing trend in the risk of cervical cancer with reducing level of serum folate (chi-squared trend test of P = 0.000). Meanwhile, low-level of serum folate and HPV16-infection showed significant interaction in the development of cervical cancer, with likelihood ratio test of G = 5.56, P = 0.02.

CONCLUSIONResults indicated that low levels of folate might increase the risk of cervical cancer, and potential synergistic action might exist between low level of serum folate and HPV16 in the development of cervical cancer.

Case-Control Studies ; Diet ; Female ; Folic Acid ; blood ; Folic Acid Deficiency ; complications ; Human papillomavirus 16 ; genetics ; isolation & purification ; Humans ; Papillomavirus Infections ; complications ; Uterine Cervical Neoplasms ; blood ; etiology ; virology