[Jiawei Baitouweng Decoction affects intestinal mucosal tight junction proteins in rats with ulcerative colitis through p38 MAPK-MLCK signaling pathway].

The aim of this paper was to explore the effect and mechanism of Jiawei Baitouweng Decoction(JWBTW) against ulcerative colitis(UC) from the perspective of intestinal mucosal tight junction proteins. From 60 SPF-grade male SD rats, 10 were randomly selected as the blank control, and the remaining 50 were treated with 3% dextran sodium sulfate(DSS) solution to induce UC and then randomized into the model group, mesalazine group, and low-, medium-, and high-dose JWBTW( L-JWBTW, M-JWBTW and H-JWBTW) groups, with 10 rats in each group. After successive medication for 14 days, the rat general conditions like body weight and stool were observed and the disease activity index(DAI) was calculated. The pathological changes in colon tissue was observed under a microscope for injury severity scoring and histopathological scoring. The serum endotoxin content was determined by limulus assay, followed by the measurement of protein expression levels of ZO-1, occludin, claudin-1, p38 MAPK, MLCK, MLC2 and p-MLC in colon tissue by Western blot. The results showed that compared with the blank group, the model group exhibited significantly reduced body weight, elevated DAI, injury severity and histopathological scores and serum endotoxin content, up-regulated protein expression levels of p38 MAPK, MLCK, MLC2 and p-MLC, and down-regulated ZO-1, occludin and claudin-1. Compared with the model group,mesalazine and JWBTW at each dose obviously increased the body weight, lowered the DAI, injury severity and histopathological scores and serum endotoxin content, down-regulated the protein expression levels of p38 MAPK, MLCK, MLC2 and p-MLC, and up-regulated the ZO-1, occludin and claudin-1, with the most obvious changes noticed in the H-JWBTW group. All these have indicated that JWBTW exerts the therapeutic effect against UC by inhibiting the activation of p38 MAPK/MLCK pathway, reversing the protein expression levels of occludin, claudin-1 and ZO-1, decreasing the serum endotoxin content, promoting the repair of intestinal mucosal mechanical barrier, maintaining the integrity of tight junctions, and reducing the permeability of intestinal mucosa.

Role of TLR4/MyD88 Signaling Pathway in the Occurrence and Development of Uremia-Induced Myocardial Hypertrophy and Possible Mechanism.

The morbidity and mortality of cardiovascular disease (CVD) are relatively high. Studies have shown that most patients with chronic kidney disease (CKD) die from cardiovascular complications. Clinically, the pathophysiological state in which heart disease and kidney disease are causal and influence each other is called cardiorenal syndrome (CRS). Myocardial hypertrophy is the key stage of the heart structure changing from reversible to irreversible. It is an important pathophysiological basis for heart failure. Therefore, this study intends to start with the end-stage uremic phase of CKD to construct an animal model of uremia in rats to study the relationship between uremia, TLR4/MyD88 signaling pathway, and myocardial hypertrophy. The results showed that the uremic rats showed slow weight gain and were thinner. At 12 weeks (w), the serum creatinine and urea nitrogen of the uremic rats increased, and the global hypertrophy index increased. Detecting the expression of Toll-like receptor 4 (TLR4) and myeloid differentiation factor (MyD88) in blood samples of rats, we found that the expression of TLR4 and MyD88 increased at 12 w in the uremia group; pathological observation showed that at 4 weeks of uremia model rats, renal tissue compensatory hypertrophy, renal fibrous membrane proliferation, renal parenchyma atrophy, a large number of fibrous proliferation and inflammatory cell infiltration in the interstitium, and protein casts in the renal tubules were observed. Myocardial cells were obviously hypertrophy and disordered. At 12 w, renal tubules were obviously expanded, the epithelium was flat, the brush border disappeared, and the interstitial fibrous connective tissue of the myocardial tissue was proliferated. The detection of TLR4 and MyD88 in kidney tissue and myocardial tissue revealed that the positive expression of TLR4 and MyD88 gradually increased over time. Therefore, the final result of the study is that uremia can gradually lead to myocardial hypertrophy and TLR4 and MyD88 are highly expressed in serum, kidney, and myocardial tissues of uremic rats, suggesting that TLR4 and MyD88 may be related to the degree of uremic disease and the myocardium caused by it. Hypertrophy is related.

Study of Jianpi Mixture on Intestinal Microbiota of Diarrhea Irritable Bowel Syndrome Mice.

To investigate the differences in intestinal microbiota between diarrhea irritable bowel syndrome mice (IBS-D) and healthy mice and to explore the effects of Jianpi mixture on intestinal microbes' changes in IBS-D mice based on 16S rDNA sequencing analysis. 48 young ICR male mice were randomly divided into four groups (n = 12): (1) control group, (2) IBS-D group fed with distilled water, (3) IBS-D group fed with lactic acid bacteria compound, and (4) IBS-D group fed with Jianpi mixture for 14 days. At the end of the treatment period, 5 mice were randomly selected from each group, and then the changes in intestinal microbiota in the mice before and after treatment were analyzed by 16S rDNA high-throughput gene sequencing. Compared with the control group, the species richness and species diversity of intestinal microbiota in feces and intestinal mucosa of IBS-D mice were decreased (P < 0.05); IBS-D mice showed changes in composition of and in ratio of the intestinal microbiota in feces and intestinal mucosa at the level of phylum, class, order, family, genus, and species. Treatment with Jianpi mixture increased the species diversity of intestinal microbiota in IBS-D mice (P < 0.05) and the abundance of beneficial bacteria (P < 0.05) and decreased the abundance of harmful bacteria (P < 0.05) at the level of phylum and genus. Compared with healthy mice, the species richness and species diversity of intestinal microbiota of IBS-D mice are decreased. The intervention with Jianpi mixture can improve its diversity and regulate the equilibrium between beneficial and harmful bacteria.

Rapid and undamaged analysis of crude and processed Radix Scrophulariae by Fourier transform infrared spectroscopy coupled with soft independent modeling of class analogy.

OBJECTIVE: The main objective of this work is to determine the feasibility of identification of crude and processed Radix Scrophulariae using the Fourier transform infrared spectroscopy couple with soft independent modeling of class analogy (FT-IR-SIMCA). MATERIALS AND METHODS: A total of 50 different crude Radix Scrophulariae was used to product processed ones. The spectra were acquired by FT-IR spectroscopy using a diffuse reflectance fiber optic probe. For the multivariate analysis, SIMCA was used. Results showed that FT-IR-SIMCA was useful to discriminate the processed Radix Scrophulariae samples from crude samples. These samples could be successfully classified by SIMCA. RESULTS: In all cases, the recognition and rejection rates were 97.8% and 100%, respectively. When testing with the blind sample that was picked out from the chosen samples, the accuracy was up to 90%. CONCLUSION: It means that the methodology is capable of accurately separating processed Radix Scrophulariae from crude samples.

Epigenetic profiles in children with a neural tube defect; a case-control study in two populations.

Folate deficiency is implicated in the causation of neural tube defects (NTDs). The preventive effect of periconceptional folic acid supplement use is partially explained by the treatment of a deranged folate-dependent one carbon metabolism, which provides methyl groups for DNA-methylation as an epigenetic mechanism. Here, we hypothesize that variations in DNA-methylation of genes implicated in the development of NTDs and embryonic growth are part of the underlying mechanism. In 48 children with a neural tube defect and 62 controls from a Dutch case-control study and 34 children with a neural tube defect and 78 controls from a Texan case-control study, we measured the DNA-methylation levels of imprinted candidate genes (IGF2-DMR, H19, KCNQ1OT1) and non-imprinted genes (the LEKR/CCNL gene region associated with birth weight, and MTHFR and VANGL1 associated with NTD). We used the MassARRAY EpiTYPER assay from Sequenom for the assessment of DNA-methylation. Linear mixed model analysis was used to estimate associations between DNA-methylation levels of the genes and a neural tube defect. In the Dutch study group, but not in the Texan study group we found a significant association between the risk of having an NTD and DNA methylation levels of MTHFR (absolute decrease in methylation of -0.33% in cases, P-value = 0.001), and LEKR/CCNL (absolute increase in methylation: 1.36% in cases, P-value = 0.048), and a borderline significant association for VANGL (absolute increase in methylation: 0.17% in cases, P-value = 0.063). Only the association between MTHFR and NTD-risk remained significant after multiple testing correction. The associations in the Dutch study were not replicated in the Texan study. We conclude that the associations between NTDs and the methylation of the MTHFR gene, and maybe VANGL and LEKKR/CNNL, are in line with previous studies showing polymorphisms in the same genes in association with NTDs and embryonic development, respectively.

Thymidylate synthase polymorphisms and risk of conotruncal heart defects.

In this study, we investigated whether the two TYMS functional variants (28 bp VNTR and 1494del6) (275 cases and 653 controls) and six selected SNPs (265 case infants, 535 control infants; 169 case mothers and 276 control mothers) were associated with risks of conotruncal heart defects. Further, we evaluated interaction effects between these gene variants and maternal folate intake for risk of CTD. Cases with diagnosis of single gene disorders or chromosomal aneusomies were excluded. Controls were randomly selected from area hospitals in proportion to their contribution to the total population of live-born infants. DNA samples were collected using buccal brushes or drawn from the repository of newborn screening blood specimens when available. Genetic variants were treated as categorical variables (homozygous referent, heterozygote, homozygous variant). Odds ratios and 95% confidence intervals (CI) were computed to estimate risks among all subjects, Hispanic and non-Hispanic whites, respectively, using logistic regression. Gene-folate interactions were assessed for these variants by adding an interaction term to the logistic model. A dichotomized composite variable, "combined folate intake," was created by combining maternal peri-conceptional use of folic acid-containing vitamin supplements with daily dietary intake of folate. In general, the results do not show strong gene-only effects on risk of CTD. We did, however, observe a 3.6-fold increase in CTD risk (95% CI: 1.1-11.9) among infants who were homozygotes for the 6 bp deletion in the 3'-untranslated region (UTR) (1694del6) and whose mothers had low folate intake during the peri-conceptional period.

Maternal and infant gene-folate interactions and the risk of neural tube defects.

Neural tube defects (NTDs) are common, serious malformations with a complex etiology that suggests involvement of both genetic and environmental factors. The authors evaluated maternal or offspring folate-related gene variants and interactions between the gene variants and maternal intake of folates on the risk of NTDs in their offspring. A case-control study was conducted on mothers and/or their fetuses and infants who were born in California from 1999 to 2003 with an NTD (cases n = 222, including 24 mother-infant pairs) or without a major malformation (controls n = 454, including 186 mother-infant pairs). Maternal intake of folates was assessed by food frequency questionnaire and genotyping was performed on samples from mothers and infants. For mothers in the lowest folate-intake group, risk of NTDs in offspring was significantly decreased for maternal MTHFR SNPs rs1476413, rs1801131, and rs1801133 (odds ratio [OR] = 0.55, 80% confidence interval [CI]: 0.20, 1.48; OR = 0.58, 80% CI: 0.24, 1.43; OR = 0.69, 80% CI: 0.41, 1.17, respectively), and TYMS SNPs rs502396 and rs699517 (OR = 0.91, 80% CI: 0.53, 1.56; OR = 0.70, 80% CI: 0.38, 1.29). A gene-only effect was observed for maternal SHMT1 SNP rs669340 (OR = 0.69, 95% CI: 0.49, 0.96). When there was low maternal folate intake, risk of NTDs was significantly increased for infant MTHFD1 SNPs rs2236224, rs2236225, and rs11627387 (OR = 1.58, 80% CI: 0.99, 2.51; OR = 1.53, 80% CI: 0.95, 2.47; OR = 4.25, 80% CI: 2.33, 7.75, respectively) and SHMT1 SNP rs12939757 (OR = 2.01, 80% CI: 1.20, 3.37), but decreased for TYMS SNP rs2847153 (OR = 0.73, 80% CI: 0.37, 1.45). Although power to detect interaction effects was low for this birth defects association study, the gene-folate interactions observed in this study represent preliminary findings that will be useful for informing future studies on the complex etiology of NTDs.

A novel magnetic nanoparticle hyperthermia combined with ACMF-dependant drug release by DAMMs injection in VX-2 liver tumors.

In this paper, we investigated the feasibility and effect of a novel combination therapy of magnetic nanoparticles (MNPs) hyperthermia with anticancer drugs for solid malignancies using doxorubicin-loaded alginate-templated magnetic microcapsules (DAMMs) in an animal liver cancer model. Firstly, DAMMs containing 18 nm gamma-Fe2O3 with doxorubicin (Dox) were synthesized and characterized. Then, the particular behavior of Dox release under external alternating current magnetic filed (ACMF) was tested in vitro. Moreover, to obtain accurate thermotherapy, the dose of DAMMs and temperature rise were computed by Hyperthermia treatment plan (HTP) and a fiber optic temperature sensor (FOTS) was used to monitor the temperature rise during treatments on VX-2 liver tumor-bearing rabbits. Furthermore, the therapeutic effect was studied by histopathological examinations and animal survival. The results showed that ACMF can induce Dox fast release during the treatment and the high MNPs content of DMMAs guaranteed the temperature rise for hyperthermia in tumors. The rabbits bearing VX-2 tumors in the magnetic hyperthermia using DMMAs group gained the most tumor necrosis and survival time. It was indicated that DAMMs-based magnetic hyperthermia could be a feasible and effective remedy which could be targeted at liver tumors by dual effects of hyperthermia and chemotherapy.

Effects of dietary fish oil on the depletion of carcinogenic PAH-DNA adduct levels in the liver of B6C3F1 mouse.

Many carcinogenic polycyclic aromatic hydrocarbons (PAHs) and their metabolites can bind covalently to DNA. Carcinogen-DNA adducts may lead to mutations in critical genes, eventually leading to cancer. In this study we report that fish oil (FO) blocks the formation of DNA adducts by detoxification of PAHs. B6C3F1 male mice were fed a FO or corn oil (CO) diet for 30 days. The animals were then treated with seven carcinogenic PAHs including benzo(a)pyrene (BaP) with one of two doses via a single intraperitoneal injection. Animals were terminated at 1, 3, or 7 d after treatment. The levels of DNA adducts were analyzed by the (32)P-postlabeling assay. Our results showed that the levels of total hepatic DNA adducts were significantly decreased in FO groups compared to CO groups with an exception of low PAH dose at 3 d (P = 0.067). Total adduct levels in the high dose PAH groups were 41.36±6.48 (Mean±SEM) and 78.72±8.03 in 10(9) nucleotides (P = 0.011), respectively, for the FO and CO groups at 7 d. Animals treated with the low dose (2.5 fold lower) PAHs displayed similar trends. Total adduct levels were 12.21±2.33 in the FO group and 24.07±1.99 in the CO group, P = 0.008. BPDE-dG adduct values at 7 d after treatment of high dose PAHs were 32.34±1.94 (CO group) and 21.82±3.37 (FO group) in 10(9) nucleotides with P value being 0.035. Low dose groups showed similar trends for BPDE-dG adduct in the two diet groups. FO significantly enhanced gene expression of Cyp1a1 in both the high and low dose PAH groups. Gstt1 at low dose of PAHs showed high levels in FO compared to CO groups with P values being 0.014. Histological observations indicated that FO played a hepatoprotective role during the early stages. Our results suggest that FO has a potential to be developed as a cancer chemopreventive agent.

Association of reduced folate carrier gene polymorphism and maternal folic acid use with neural tube defects.

This study was designed to investigate whether the risk for neural tube defects (NTDs) was associated with reduced folate carrier gene (RFC1 A80G) polymorphism and/or with the interaction between the RFC1 gene and maternal periconceptional use of folic acid. One hundred four nuclear families with NTDs and 100 non-malformed control families were sampled to investigate the potential interaction between maternal or the offspring's RFC1 (A80G) genotypes and the maternal periconceptional use of folic acid through a population-based case-control study. RFC1 (A80G) genotypes were detected using PCR-restricted fragment length polymorphism (PCR-RFLP). Mother who had the GG genotype and did not take folic acid had an elevated risk for NTDs (OR = 5.43, 95% CI = 1.68-18.28) as compared to the mother who had AA or GA genotype and took maternal periconceptional folic acid. The interactive coefficient was 1.12 between maternal GG genotype and the periconceptional folic acid non-use. The risk for having an infant with NTDs was 8.80 (95% CI = 2.83-28.69) for offspring with the GG genotype, as compared to the offspring with AA or GA genotype among the mothers who did not take folic acid supplements. The interactive coefficient was 1.45 for offspring with the GG genotype and without maternal periconceptional supplementation of folic acid. Our findings suggest that there is a potential gene-environment interaction on the risk of NTDs between maternal or offspring RFC1 GG genotype and maternal periconceptional intake of folic acid. The RFC1 is likely to be an important candidate gene in folate transportation and RFC1 GG genotype (A80G) may be associated with an increased risk for NTDs in this Chinese population.

Cardiovascular abnormalities in Folr1 knockout mice and folate rescue.

BACKGROUND: Periconceptional folic acid supplementation is widely believed to aid in the prevention of neural tube defects (NTDs), orofacial clefts, and congenital heart defects. Folate-binding proteins or receptors serve to bind folic acid and 5-methyltetrahydrofolate, representing one of the two major mechanisms of cellular folate uptake. METHODS: We herein describe abnormal cardiovascular development in mouse fetuses lacking a functional folate-binding protein gene (Folr1). We also performed a dose-response study with folinic acid and determined the impact of maternal folate supplementation on Folr1 nullizygous cardiac development. RESULTS: Partially rescued preterm Folr1(-/-) (formerly referred to as Folbp1) fetuses were found to have outflow tract defects, aortic arch artery abnormalities, and isolated dextracardia. Maternal supplementation with folinic acid rescued the embryonic lethality and the observed cardiovascular phenotypes in a dose-dependant manner. Maternal genotype exhibited significant impact on the rescue efficiency, suggesting an important role of in utero folate status in embryonic development. Abnormal heart looping was observed during early development of Folr1(-/-) embryos partially rescued by maternal folinic acid supplementation. Migration pattern of cardiac neural crest cells, genetic signals in pharyngeal arches, and the secondary heart field were also found to be affected in the mutant embryos. CONCLUSIONS: Our observations suggest that the beneficial effect of folic acid for congenital heart defects might be mediated via its impact on neural crest cells and by gene regulation of signaling pathways involved in the development of the pharyngeal arches and the secondary heart field.

Variable contribution of the MTHFR C677T polymorphism to non-syndromic cleft lip and palate risk in China.

Non-syndromic cleft lip with or without cleft palate (nsCL/P) is one of the most common craniofacial malformations among newborn infants. It has been demonstrated that periconceptional folic acid supplementation may reduce the occurrence of offspring with clefts, particularly in the North China; however, the mechanism remains unknown. Our study of a thermolabile polymorphism (C677T) of methylenetetrahydrofolate reductase (MTHFR) gene in 170 Chinese case-parent triads revealed a moderate association between this MTHFR polymorphism and nsCL/P in a population from North China, but not in a population from South China. Moreover, the study revealed that the heterozygous parents in the North were about twice as likely to transmit the high-risk T allele to affected cases, as that observed in the South (OR = 2.24, 95% CI: 1.08-4.65). Thus, the MTHFR polymorphism is a significant risk factor for nsCL/P in this Northern Chinese population. Our study suggested possible genetic heterogeneity in the development of nsCL/P among Northern and Southern populations in China.

Genetic variation of infant reduced folate carrier (A80G) and risk of orofacial defects and congenital heart defects in China.

PURPOSE: This study was designed to investigate whether the risks of congenital heart defects (CHD) and orofacial defects were influenced by a polymorphism of the offspring's RFC1 or by an interaction between the RFC1 gene and maternal periconceptional use of folic acid. METHODS: A case-control study was conducted. A total of 82 families with a child affected by cleft lip with or without cleft palate (CLP), 67 families with a child-affected by CHD, and 100 nonmalformed control families were genotyped using PCR-RFLP. RFC1 G allele was tested through family-based association test. RESULTS: Among mothers who did not use folic acid, the risks of 4.03 (95% CI = 1.33-12.77) for the G80/G80 genotype and 4.14 (95% CI = 1.06-16.82) for the G80/A80 genotype were observed relative to the A80/A80 genotype for CHD offspring. In family-based association tests (FBAT), offspring carrying the G allele for RFC1 is at increased risk for CHD (Z = 2.140, p < .05). No significant association was found between either RFC1 genotype or maternal folic acid supplementation and the risks of CLP. CONCLUSIONS: Our findings suggest that the RFC1 G allele is likely to be an important candidate gene in folate transport and to be associated with risk for CHD. This study found modest evidence for a gene-nutrient interaction between offspring RFC1 genotype and periconceptional intake of folic acid on the risk of congenital heart defects.

A known functional polymorphism (Ile120Val) of the human PCMT1 gene and risk of spina bifida.

Folate binding protein 1 (Folr1) knockout mice with low maternal folate concentrations have been shown to be excellent animal models for human folate-responsive neural tube defects (NTDs). Previous studies using the Folr1 knockout mice revealed that maternal folate supplementation up-regulates the expression of the PCMT1 gene in Folr1 nullizygous neural tube tissue during neural tube closure. PCMT1 encodes the protein repair enzyme l-isoaspartate (d-aspartate) O-methyltransferase (PIMT) that converts abnormal d-aspartyl and l-isoaspartyl residues to the normal l-aspartyl form. PIMT is known to protect certain neural cells from Bax-induced apoptosis. Pcmt1-deficient mice present with abnormal AdoMet/AdoHcy homeostasis. We hypothesized that a known functional polymorphism (Ile120Val) in the human PCMT1 gene is associated with an increased risk of folate-responsive human NTDs. A case-control study was conducted to investigate a possible association between this polymorphism and risk of spina bifida. Compared to the Ile/Ile and Ile/Val genotypes, the homozygous Val/Val genotype showed decreased risk for spina bifida (adjusted odds ratio=0.6, 95% confidence interval: 0.4-0.9). Our results showed that the Ile120Val polymorphism of PCMT1 gene is a genetic modifier for the risk of spina bifida. Val/Val genotype was associated with a reduction in risk for spina bifida.

[Epidemiological study on reduced folate carrier gene(RFC1 A80G) polymorphism and other risk factors of neural tube defects].

OBJECTIVE: To study the reduced folate carrier gene (RFC1) A80G polymorphism and other factors influence on children with neural tube defects (NTDs) and provide the epidemiological evidence for finding genetic marker of NTDs. METHODS: RFC1(A80G) genotypes were detected using polymerase chain reaction-restriction fragment length polymorphism (RFLP-PCR) for blood DNA of 104 trios with NTDs-affected by child, and the 100 control families without child-affected by any birth defects. We performed the analysis of multifactors logistic regression for RFC1 genotypes and other factors in order to investigate the RFC1 genotype of the nuclear families and maternal periconceptional folic acid supplementation influence on NTDs independently. Transmission/disequilibrium test (TDT) for the RFC1 genotype of NTDs and control pedigree were carried out. RESULTS: The RFC1 G allele frequency of children with NTDs (64.42%) was higher than that of the control children (52.53%), and there was the significant difference between them (chi(2)=5.9198, P<0.05). We observed that the infants of the GG genotype were associated with a 2.56-fold increased risk of NTDs when compared with the AA genotype (95% CI=1.04-6.36), The risk of mothers who did not take folic acid for having an NTDs-affected infants was 7.69 (95% CI=2.86-21.75). There were significant differences between cases and controls in the other risk factors, such as paternal age (> or =30), maternal fever during the early pregnancy, the history of maternal spontaneous abortion. In the logistic regression analysis, of multifactors the three factors, for example, the offspring of the RFC1 GG genotype (OR=2.91, 95% CI=1.35-6.30), maternal periconceptional folic acid supplementation (OR=4.32, 95% CI=1.62-11.55), maternal fever during the early pregnancy, had the statistic significance for the risk of NTDs. There was the evidence of an association between G allele and the risk of the maternal having a child with NTDs (OR=1.56, 95% CI=1.07-2.28) in TDT analysis. CONCLUSION: Our findings indicate that the RFC1 genotype (GG) is a possible susceptible gene marker for an increased NTDs risk in this Chinese population, and there is a potential influence on the risk of NTDs in maternal periconceptional folic acid supplementation, and maternal fever during the early pregnancy.

Interaction between maternal periconceptional supplementation of folic acid and reduced folate carrier gene polymorphism of neural tube defects.

OBJECTIVE: To search the interaction between reduced folate carrier gene (RFC1 A80G) polymorphism of children with neural tube defects (NTDs) and maternal periconceptional no supplementation of folic acid. The purpose is to provide the epidemiological evidence for finding genetic marker of NTDs. METHODS: RFC1 (A80G) genotype was detected using PCR-restricted fragment length polymorphism for the blood DNA of 104 trios with NTDs-affected child, and 100 control families with non-malformed control children. The authors investigated the gene-environment interactions between the offspring RFC1 genotype and maternal periconceptional folic acid supplementation through a case-control study. RESULTS: It was observed that the offspring with the GG genotype were associated with a 2.56-fold increased risk of NTDs when compared to those with the AA genotype (OR = 2.56; 95% CI = 1.04-6.36) in this population under investigation. The risk of mothers who did not take folic acid for having an NTDs-affected infants was 7.69 (95% CI = 2.86-21.75). Among the mothers who did not utilize folic acid supplements, the NTDs risk was 3.30 (95% CI = 1.15-9.65) for offspring with the GG genotype, compared to the reference (AA) genotype. Children who had the GG genotype and whose mothers did not take folic acid had an elevated risk for NTDs (OR = 8.80, 95% CI = 2.86 - 29.82), compared to "offspring with AA or GA genotype" and "maternal folic acid use", the interactive coefficient being 1.45. CONCLUSION: The above findings indicate that the RFC1 genotype (GG) is a possible susceptible gene marker for an increased NTDs risk in Chinese population, and there is a potential gene-nutrient interaction between offspring RFC1 GG genotype and maternal periconceptional intake of folic acid on the risk of NTDs. However,the sample size of this study was limited, a larger sample of population-based study is required to pursue the initial observation.

Are the betaine-homocysteine methyltransferase (BHMT and BHMT2) genes risk factors for spina bifida and orofacial clefts?

Abnormalities in folate and/or homocysteine metabolism may adversely influence embryonic development, leading to the birth of infants with a variety of congenital malformations, including neural tube defects (NTDs) and craniofacial abnormalities. Based upon suggestive evidence that periconceptional folic acid supplementation is effective in preventing a significant proportion of the aforementioned birth defects, genetic variation in the folate biosynthetic pathways may influence the infant's susceptibility to these birth defects. The goal of our study was to investigate sequence variations in the betaine-homocysteine methyltransferase (BHMT) and betaine-homocysteine methyltransferase (BHMT2) genes as modifiers of risk of spina bifida, cleft palate, and cleft lip and palate. The results of this study indicated that individuals homozygous for the single nucleotide polymorphism R239Q in BHMT did not have elevated risks for spina bifida. Genotype frequencies for the BHMT2 rs626105 polymorphism also did not reveal any elevated risks for spina bifida, and only a modest, imprecise elevation of risk for orofacial clefts. The results of these experiments suggest that variants of the BHMT/BHMT2 genes in infants do not substantially contribute to the risk of spina bifida or orofacial clefts in our study population.

Reduced folate carrier gene is a risk factor for neural tube defects in a Chinese population.

BACKGROUND: There is a considerable body of data demonstrating that periconceptional supplementation of folic acid can prevent a significant proportion of neural tube defects (NTDs). At present, the mechanism by which folic acid exerts its beneficial effect remains unknown. Folate transporter genes, including the reduced folate carrier gene (RFC1), have been proposed as NTD risk factors. METHODS: The study population included 104 nuclear families with NTDs and 100 nonmalformed control families. We investigated the possible association between a common RFC1 polymorphism (A80G) and NTD risk among offspring, as well as potential gene-environment interactions between the infant RFC1 genotype and maternal periconceptional use of folic acid through a population-based case-control study. RESULTS: We observed that the infants of the GG genotype were associated with a 2.56-fold increased risk of NTDs when compared to the AA genotype (odds ratio [OR], 2.56; 95% confidence interval [CI], 1.04-6.36) in our study population. Among mothers who did not utilize folic acid supplements, the risk for having a child with an NTD was 3.30 (95% CI, 1.15-9.65) for offspring with the GG genotype, compared to the reference (AA) genotype. Children who had the GG genotype and whose mothers did not take folic acid had an elevated risk for NTDs (OR, 8.80; 95% CI, 2.83-28.69), compared to offspring with the AA and GA genotypes whose mothers utilized folic acid supplements. CONCLUSIONS: Our findings suggest that the RFC1 G allele is likely to be an important genetic factor in determining folate transport and subsequently may be a risk factor for NTDs in this Chinese population.

[Study on the association between reduced folate carrier gene polymorphism and congenital heart defects and cleft lip with or without cleft palate].

OBJECTIVE: To study the association between reduced folate carrier gene (RFC1) polymorphism and congenital heart defects (CHD) as well as cleft lip with or without cleft palate (CLP) and to provide epidemiological evidence on genetic markers of CHD and CLP. METHODS: RFC1 (A80G) genotype was detected using RFLP-PCR for blood DNA of the 67 triads with nonsyndromic CHD-affected child, the 82 triads with child-affected cleft lip with or without CLP and the 100 control families without child-affected birth defects. We performed a family-based association test and analyzed the interaction between RFC1 A80G genotype and maternal periconceptional supplementation of folic acid. RESULTS: Offspring of mothers who did not take folic acid had an elevated risk for CHD when comparing with offspring of mothers who did (OR = 2.68, 95% CI: 1.14 - 6.41). There was a statistical association between the risk of CHD and maternal periconceptional folic acid supplementation (chi(2) = 6.213, P < 0.05). In the family-based association test, G allele was positively associated with an increased risk for children CHD (Z = 2.140, P < 0.05) while G allele of RFC1 (A80G) polymorphism might increase the risk for CHD. Elevated risks for either CLP group were not observed between RFC1 genotype using or not using folic acid. CONCLUSION: Our findings suggested that the G allele was likely to be a genetically susceptible allele for CHD. There was possible association between offspring with GG, GA genotype and maternal periconceptional folicacid deficiency.

Evaluation of infant methylenetetrahydrofolate reductase genotype, maternal vitamin use, and risk of high versus low level spina bifida defects.

BACKGROUND: Several studies have suggested that homozygosity for the C677T 5,10-methylenetetrahydrofolate reductase (MTHFR) variant is a potential risk factor for neural tube defects (NTDs), as individuals homozygous for the C677T allele have slightly elevated homocysteine concentrations under conditions of low folic acid intake. It has been hypothesized that maternal folic acid supplementation prevents NTDs by partially correcting reduced MTHFR activity associated with the variant form of the enzyme. METHODS: Genomic DNA was extracted from newborn screening blood spots obtained from 145 infants with spina bifida (SB) and 260 nonmalformed control infants. The MTHFR C677T genotype was determined by restriction enzyme digestion of PCR amplification products with Hinf1. We investigated whether infant MTHFR genotype influenced the risk for the anatomic level of the SB lesion (high vs. low); we also explored whether maternal vitamin use influenced this risk. RESULTS: Compared to controls, the frequency of SB infants with the homozygous 677 TT genotype was greatest in those infants with high level SB defects (26%; odds ratio [OR] = 2.9; 95% confidence interval [CI] = 0.9-10.1) than for those with low level SB defects (22%; OR = 1.8; 95% CI = 0.9-3.2). Furthermore, homozygous 677TT infants whose mothers did not use vitamins containing folic acid had a modestly increased risk of SB (OR = 1.8; 95% CI = 0.8-3.9), with this risk increasing more than three-fold (OR = 5.5; 95% CI = 0.8-28.1) for those infants with high level SB defects whose mothers did not use vitamins. CONCLUSIONS: Based upon our observations, it is suggested that the association between the infant MTHFR homozygous variant genotype and spina bifida risk may be conditional upon both lesion level and maternal vitamin use.