Dihydrofolate reductase (DHFR) is an enzyme that catalyzes the reduction of dihydrofolate (DHF) to tetrahydrofolate (THF). Chemotherapy drugs such as methotrexate help to slow the progression of cancer by limiting the...Dihydrofolate reductase (DHFR) is an enzyme that catalyzes the reduction of dihydrofolate (DHF) to tetrahydrofolate (THF). Chemotherapy drugs such as methotrexate help to slow the progression of cancer by limiting the ability of dividing cells to make nucleotides by competitively inhibiting DHFR. Nonsteroidal anti-inflammatory drugs (NSAIDs) have been previously reported to exhibit competitive inhibition of DHFR, in addition to their primary action on cyclooxygenase enzymes. This interaction interferes with the enzymatic reduction of dihydrofolate to tetrahydrofolate, thereby impeding the folate metabolism pathway essential for nucleotide synthesis and cell proliferation. This activity stems from their structural resemblance to the p-aminobenzoyl-l-glutamate (pABG) moiety of folate, a substrate of DHFR. It has been established that NSAIDs containing a salicylate group (which has structural similarities to pABG), such as diflunisal, exhibit stronger DHFR-binding activity. In this study, we synthesized salicylate derivatives of naproxen with the aim of exploring their potential as inhibitors of DHFR. The interactions between these derivatives and human DHFR were characterized using a combination of biochemical, biophysical, and structural methods. Through polyacrylamide gel electrophoresis (PAGE) analysis, enzymatic assays, and quantitative ELISA, we investigated the binding affinity and inhibitory potency of the synthesized salicylate derivatives towards DHFR. The findings of this study suggest the potential of salicylate derivatives of naproxen as promising candidates for the inhibition of DHFR, thereby offering novel therapeutic opportunities for modulating the inflammatory process through multiple pathways. Further optimization of these derivatives could lead to the development of more efficacious dual-targeted analogs with enhanced therapeutic benefits.展开更多
Objective This study aimed to evaluate the associations of serum folate and/or vitamin B12 concentrations with obesity among Chinese children and adolescents.Methods A cross-sectional study was conducted including 3,0...Objective This study aimed to evaluate the associations of serum folate and/or vitamin B12 concentrations with obesity among Chinese children and adolescents.Methods A cross-sectional study was conducted including 3,079 Chinese children and adolescents,aged 6 to 17 years,from Jiangsu,China.Anthropometric indices,such as,children's body mass index(BMI),BMI z-scores,waist circumference,and waist-to-height ratio were utilized.Multivariable linear regression and generalized additive models were used to investigate the associations of serum folate and vitamin B12 levels with anthropometric indices and odds of obesity.Results We observed that serum vitamin B12 concentrations were inversely associated with all anthropometric indices and the odds of general obesity[odds ratio(OR)=0.68;95%confidence interval(CI)=0.59,0.78]and abdominal obesity(OR=0.68;95%CI=0.60,0.77).When compared to participants with both serum vitamin levels in the two middle quartiles,those with both serum folate and vitamin B12 levels in the highest quartile were less prone to general(OR=0.31,95%CI=0.19,0.50)or abdominal obesity(OR=0.46,95%CI=0.31,0.67).Conversely,participants with vitamin B12 levels in the lowest quartile alongside folate levels in the highest quartile had higher odds of abdominal obesity(OR=2.06,95%CI=1.09,3.91).Conclusion Higher serum vitamin B12 concentrations,but not serum folate concentrations,were associated with lower odds of childhood obesity.Children and adolescents with high levels of vitamin B12 and folate were less likely to be obese.展开更多
Objective Circular RNAs(circRNAs)participate in several important pathological processes and have been used in the diagnosis and treatment of various diseases.This study aimed to investigate the role of circRNAs in ne...Objective Circular RNAs(circRNAs)participate in several important pathological processes and have been used in the diagnosis and treatment of various diseases.This study aimed to investigate the role of circRNAs in neural tube defects(NTDs).Method We characterized circRNA-associated competitive endogenous RNA(ceRNA)networks in brain tissue of low folate-induced NTDs mouse at embryonic day 13.5 by high-throughput sequencing.The expression levels of Circzfp644,miR-20-5p and Gas7 were detected by RT-PCR.Gas7 and Circzfp644functions were determined by miRNA-mimics and inhibitors in mouse teratocarcinoma cells(F9 cells),and luciferase gene reporter assay was assessed in the F9 cells.In addition,the expression levels of Circzfp644,miR-20-5p and Gas7 were determined by Nanostring in human NTDs tissues.Results We detected 57 circRNA transcripts,16 miRNAs,and 148 mRNAs that were significantly dysregulated in NTDs brain tissues compared with their expression levels in control(normal)tissues.Circzfp644 shared miRNA response elements with the growth arrest specific 7(Gas7)gene and competitively bound with miR-20-5p to increase the expression of Gas7.Downregulation of Circzfp644and Gas7 and upregulation of miR-20-5p were found in human NTD tissue.Conclusion This study provides new perspectives on the role of circRNAs in nervous system development and the pathogenesis of NTDs.展开更多
AIM:To evaluate joint effects of Methylentetra-hydrofolate reductase(MTHFR) C677T genotypes,and serum folate/vitamin B12 concentrations on promoter methylation of tumor-associated genes among Iranian colorectal cancer...AIM:To evaluate joint effects of Methylentetra-hydrofolate reductase(MTHFR) C677T genotypes,and serum folate/vitamin B12 concentrations on promoter methylation of tumor-associated genes among Iranian colorectal cancer patients. METHODS:We examined the associations between MTHFR C677T genotype,and promoter methylation of P16,hMLH1,and hMSH2 tumor-related genes among151 sporadic colorectal cancer patients. The promoter methylation of tumor-related genes was determined by methylation-specific PCR. Eighty six patients from whom fresh tumor samples were obtained and 81 controls were also examined for serum folate and vitamin B12 concentrations by a commercial radioimmunoassay kit. RESULTS:We found 29.1% of cases had tumors with at least one methylated gene promoter. In case-case comparison,we did not find a significant association between methylation in tumors and any single genotype. However,in comparison to controls with the CC genotype,an increased risk of tumor methylation was associated with the CT genotype(OR = 2.5;95% CI,1.1-5.6) . In case-case comparisons,folate/vitamin B12 levels were positively associated with tumor methylation. Adjusted odds ratios for tumor methylation in cases with high(above median) versus low(below median) serum folate/vitamin B12 levels were 4.9(95% CI,1.4-17.7) ,and 3.9(95% CI,1.1-13.9) ,respectively. The frequency of methylated tumors was significantly higher in high methyl donor than low methyl donor group,especially in those with MTHFR CT(P = 0.01) ,and CT/TT(P = 0.002) genotypes,but not in those with the CC genotype(P = 1.0) . CONCLUSION:We conclude that high concentrations of serum folate/vitamin B12 levels are associated with the risk of promoter methylation in tumor-specific genes,and this relationship is modified by MTHFR C677T genotypes.展开更多
AIM: To evaluate whether folate levels in mucosal tissue and some common methylenetetrahydrofolate reductase (MTHFR) variants are associated with the risk of gastric cancer through DNA methylation. METHODS: Real-time ...AIM: To evaluate whether folate levels in mucosal tissue and some common methylenetetrahydrofolate reductase (MTHFR) variants are associated with the risk of gastric cancer through DNA methylation. METHODS: Real-time PCR was used to study the expression of tumor related genes in 76 mucosal tissue samples from 38 patients with gastric cancer. Samples from the gastroscopic biopsy tissues of 34 patients with chronic superficial gastritis (CSG) were used as controls. Folate concentrations in these tissues were detected by the FOL ACS: 180 automated chemiluminescence system. MTHFR polymorphisms were analyzed by PCR-RFLP, and the promoter methylation of tumor-related genes was determined by methylation-specific PCR (MSP). RESULTS: Folate concentrations were significantly higher in CSG than in cancerous tissues. Decreased expression and methylation of c-myc accompanied higher folate concentrations. Promoter hypermethylation and loss of p16INK4A in samples with MTHFR 677CC were more frequent than in samples with the 677TT or 677CT genotype. And the promoter hypermethylation and loss of p21WAF1 in samples with MTHFR 677CT were more frequent than when 677CC or 677TT was present. The 677CT genotype showed a non-significant higher risk for gastric cancer as compared with the 677CC genotype. CONCLUSION: Lower folate levels in gastric mucosal tissue may confer a higher risk of gastric carcinogenesisthrough hypomethylation and overexpression of c-myc.展开更多
Objective This study aimed to investigate the effects of N,N-dimethylglycine(DMG) on the concentration and metabolism of plasma homocysteine(pHcy) in folate-sufficient and folate-deficient rats.Methods In this study, ...Objective This study aimed to investigate the effects of N,N-dimethylglycine(DMG) on the concentration and metabolism of plasma homocysteine(pHcy) in folate-sufficient and folate-deficient rats.Methods In this study, 0.1% DMG was supplemented in 20% casein diets that were either folatesufficient(20 C) or folate-deficient(20 CFD). Blood and liver of rats were subjected to assays of Hcy and its metabolites. Hcy and its related metabolite concentrations were determined using a liquid chromatographic system.Results Folate deprivation significantly increased pHcy concentration in rats fed 20 C diet(from 14.19 ±0.39 μmol/L to 28.49 ± 0.50 μmol/L;P < 0.05). When supplemented with DMG, pHcy concentration was significantly decreased(12.23 ± 0.18 μmol/L) in rats fed 20 C diet but significantly increased(31.56 ±0.59 μmol/L) in rats fed 20 CFD. The hepatic methionine synthase activity in the 20 CFD group was significantly lower than that in the 20 C group;enzyme activity was unaffected by DMG supplementation regardless of folate sufficiency. The activity of hepatic cystathionine β-synthase(CBS) in the 20 CFD group was decreased but not in the 20 C group;DMG supplementation enhanced hepatic CBS activity in both groups, in which the effect was significant in the 20 C group but not in the other group.Conclusion DMG supplementation exhibited hypohomocysteinemic effects under folate-sufficient conditions. By contrast, the combination of folate deficiency and DMG supplementation has deleterious effect on pHcy concentration.展开更多
The Egyptian government introduced wheat-flour fortification with iron and folic acid to reduce the incidence of neural tube defects, but suspended it for technical reasons. We previously developed novel legume foods ...The Egyptian government introduced wheat-flour fortification with iron and folic acid to reduce the incidence of neural tube defects, but suspended it for technical reasons. We previously developed novel legume foods with enhanced folate content. In this study, we investigated the efficacy of 12-week intervention with folate-enhanced foods versus folic acid supplement in improving folate status in Egyptian women. A randomized, parallel intervention trial with two active groups (n = 19, n = 18) and one blinded control group (n = 20) was executed over 12 weeks. Volunteers received either germinated legume foods and orange juice (≈250 μg/d folate) or folic acid supplement (500 μg/d) or apple juice (0 μg/d folate). Folate status was assessed by erythrocyte and plasma folate and total homocysteine (tHcy) at day 0, and after 8 and 12 weeks of intervention. After 12 weeks, mean plasma folate increased by 14 (P < 0.0001) and 12 (P < 0.0001) nmoL in the folic acid and food group, respectively. Erythrocyte folate concentration increased in the folic acid group from 614 to 912 (P < 0.0001) and in the food group from 631 to 914 nmoL (P < 0.0001). After 12 weeks, 90% of subjects in the folic acid group and 70% in the food group had erythrocyte folate concentrations exceeding 906 nmol/L. tHcy concentration was decreased by 20% (P = 0.007) and 18% (P = 0.006) in the folic acid and food group, respectively, but remained unchanged in the control group during intervention. Folate-enhanced foods effectively improve folate status in women of reproductive age. These foods could be used as a complement to folic acid fortification.展开更多
Methylenetetrahydrofolate reductase(MTHFR)is a key enzyme for the critical process of one-carbon circulation,which convert5,10-methylenetetrahydrofolate to5-methyltetrahydrofolate and participate in folate and homocys...Methylenetetrahydrofolate reductase(MTHFR)is a key enzyme for the critical process of one-carbon circulation,which convert5,10-methylenetetrahydrofolate to5-methyltetrahydrofolate and participate in folate and homocysteine conversion correlated to methyl group supply.The enzyme activity decline depends on the gene polymorphism.MTHFR impacts on the methylation process which is related to psychiatric diseases.Studies have shown association between MTHFR gene polymorphisms and mental disorders,some of which stratified by folate and cobalamin levels.In this review,we will summarize the testimony on the relationship between methylation and MTHFR polymorphism as well as the implication on psychiatric diseases by MTHFR mutation.展开更多
Objective To review the association of methylene tetrahydrofolate reductase (MTHFR) C677T mutant with coronary artery disease, as well as to highlight the results of some of these studies and to emphasize the need to ...Objective To review the association of methylene tetrahydrofolate reductase (MTHFR) C677T mutant with coronary artery disease, as well as to highlight the results of some of these studies and to emphasize the need to focus on the genetic architecture of CAD. Data SourcesData used in this article is mainly from relevant articles obtained through Pubmed, OVID and Google Scholar published from 1980 to 2008. Major studies and trials in this period were taken into account to draw accurate conclusion on the relation of those mutations in MTHFR with homocysteinemia and CAD. ResultOur analysis shows that hyperhomocysteinemia, a risk factor for occlusive arterial diseases, can be caused by disruptions of homocysteine metabolism catalyzed by MFTHR. A common alanine to valine mutation in MTHFR may contribute to mild heperhomocysteinemia in CAD. Individuals with the homozygous mutant genotype had higher plasma homocysteine, particularly when plasma folate was below the median value. ConclusionThis MTHFR mutant in the setting of insufficient folate may be a risk factor of CAD and can be regarded as a model of genetic-environmental interaction in the development of CAD.展开更多
Objective: To explore the relationship between genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), the central enzymes in folate metabolism that affects DNA meth...Objective: To explore the relationship between genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), the central enzymes in folate metabolism that affects DNA methylation and synthesis, and the risk of Down syndrome in China. Methods: Genomic DNA was isolated from the peripheral lymphocytes of 64 mothers of children with Down syndrome and 70 age matched control subjects. Polymerase chain reaction and restriction fragment length polymorphism were used to examine the polymorphisms of MTHFR 677C→T, MTRR 66A→G and the relationship between these genotypes and the risk of Down syndrome was analyzed. Results: The results show that the MTHFR 677C→T polymorphism is more prevalent among mothers of children with Down syndrome than among control mothers, with an odds ratio of 3.78 (95% confidence interval (CI), 1.78～8.47). In addition, the homozygous MTRR 66A→G polymorphism was independently associated with a 5.2-fold increase in estimated risk (95% CI, 1.90～14.22). The combined presence of both polymorphisms was associated with a greater risk of Down syndrome than the presence of either alone, with an odds ratio of 6.0 (95% CI, 2.058～17.496). The two polymorphisms appear to act without a multiplicative interaction. Conclusion: MTHFR and MTRR gene mutation alleles are related to Down syndrome, and CT, TT and GG gene mutation types increase the risk of Down syndrome.展开更多
AIM: To evaluate the associations of serum folate levelwith development, invasiveness and patient survival of gastric cancer. METHODS: In this nested case-control study, patients with newly diagnosed gastric cancer un...AIM: To evaluate the associations of serum folate levelwith development, invasiveness and patient survival of gastric cancer. METHODS: In this nested case-control study, patients with newly diagnosed gastric cancer undergoing gastrectomy were enrolled, and patients receiving chemotherapy prior to surgery, with other concurrent malignancy, or of the aboriginal and alien populations were excluded. In total, 155 gastric cancer patients and 149 healthy controls were enrolled for determination of serum folate levels and their correlation with gastric cancer. Using the median value of serum folate computed among the overall population as the cutoff value, the associations between serum folate and gastric cancer in all cases and different age and gender subgroups were analyzed by multivariate logistic regression analysis. In the patient cohort of gastric cancer, receiver-operating characteristic analyses were performed to calculate the best cutoff values of serum folate, and the associations between serum folate levels and clinicopathological features were further analyzed by multivariate regression analysis. Survival analyses were conducted using the Cox proportional hazards model.RESULTS: The mean serum folate level was significantly lower in gastric cancer patients than that in controls(3.71 ± 0.30 ng/mL vs 8.00 ± 0.54 ng/mL, P < 0.01), and folate levels were consistently lower in gastric cancer patients regardless of age and gender(all P < 0.01). Using the median serum folate value as the cutoff value, low serum folate was significantly associated with gastric cancer risk in the whole population(OR = 19.77, 95%CI: 10.54-37.06, P < 0.001) and all strata(age < 60 years OR = 17.39, 95%CI: 7.28-41.54, age ≥ 60 years(OR = 21.67, 95%CI: 8.27-56.80), males(OR = 17.95, 95%CI: 7.93-40.62), and females(OR = 20.95, 95%CI: 7.66-57.31); all P < 0.001. In the patient cohort of gastric cancer, the respective cutoff values showed that low serum folate levels were significantly associated with serosal invasion(OR = 2.54, 95%CI: 1.23-5.23), lymphatic invasion(OR = 2.23, 95%CI: 1.17-4.26), and liver metastasis(OR =6.67, 95%CI: 1.28-34.91) of gastric cancer(all P < 0.05). Serum folate level below 1.90 ng/mL was associated with poor patient survival(HR = 1.84, 95%CI: 1.04-3.27, P < 0.05) in univariate analysis.CONCLUSION: Lower serum folate levels were significantly associated with gastric cancer development and invasive phenotypes. The role of folate depletion in gastric cancer invasion warrants further study.展开更多
Objective： Nanoparticles are becoming an important method of targeted drug delivery. To evaluate the importance of folate-conjugated human serum albumin （HSA） magnetic nanoparticles （Folate-CDDP/HSA MNP）, we prep...Objective： Nanoparticles are becoming an important method of targeted drug delivery. To evaluate the importance of folate-conjugated human serum albumin （HSA） magnetic nanoparticles （Folate-CDDP/HSA MNP）, we prepared drug-loaded Folate-CDDP/HSA MNPs and characterized their features. Methods： First, folate was conjugated with HSA under the effect of a condensing agent, and the conjugating rate was evaluated by a colorimetric method using 2, 4, 6 - trinitrobenzene sulfonic acid. Second, under N., gas, Fe：~O1 magnetic nanomaterials were prepared and characterized by using transmission electron microscopy （TEM）, SEM-EDS and X-ray diffraction （XRD）. Finally, Folate-CDDP/HSA MNP was prepared by using a solvent evaporation technique. TEM was used to observe particle morphology. The particle size and distribution of the prepared complexes were determined by a Laser particle size analyzer. Drug loading volume and drug release were investigated by a high performance liquid chromatography method （HPLC） in vitro. Results： We successfully prepared folate-conjugated HSA and its conjugating rate was 27.26 μg/mg. Under TEM, Fe2O4 magnetic nanoparticles were highly electron density and had an even size distribution in the range of 10-20 nm. It was confirmed by SEM-EDS and XRD that Fe304 magnetic nanoparticles had been successfully prepared. Under TEM, drug-loaded magnetic nanoparticles were observed, which had a round shape, similar uniform size and smooth surface. Their average size was 79 nm which was determined by laser scattering, and they exhibited magnetic responsiveness. Encapsulation efficiency was 89.75% and effective drug loading was calculated to be 15.25%. The release results in vitro showed that the half release time （ta/2） of cisplatin in cisplatin Solution and Folate-CDDP/HSA MNP was 65 min and 24 h respectively, which indicated that microspheres had an obvious effect of sustained-release. Conclusion： Folate-CDDP/HSA MNPs were prepared successfully. The preparation process and related characteristics data provided a foundation for further study, including the mechanism of the nanoparticles distribution in vivo and their intake by tumor cells.展开更多
Objective：Human pancreatic cancer is one of the most common clinical malignancies.The effect of comprehensive treatment based on surgery is general.The effects of chemotherapy were not obvious mainly because of lack ...Objective：Human pancreatic cancer is one of the most common clinical malignancies.The effect of comprehensive treatment based on surgery is general.The effects of chemotherapy were not obvious mainly because of lack of targeting and chemoresistance in pancreatic cancer.This study aimed to investigate the effects of folate receptor （FR）-mediated gemcitabine FA-Chi-Gem nanoparticles with a core-shell structure by electrostatic spray on pancreatic cancer.Methods：In this study,the levels of expression of FR in six human pancreatic cancer cell lines were studied by immunohistochemical analysis.The uptake rate of isothiocyanate-labeled FA-Chi nanoparticles in FR high expression cell line COLO357 was assessed by fluorescence microscope and the inhibition rate of FA-Chi-Gem nanoparticles on COLO357 cells was evaluated by MTT assay.Moreover,the biodistribution of PEG-FA-ICGDER02-Chi in the orthotopic pancreatic tumor model was observed using near-infrared imaging and the human pancreatic cancer orthotopic xenografts were treated with different nanoparticles and normal saline control.Results：The expression of FR in COLO357 was the highest among the six pancreatic cancer cell lines.The FR mainly distributed on cell membrane and fewer in the cytoplasm in pancreatic cancer.Moreover,the absorption rate of the FA-Chi-Gem nanoparticles was more than the Chi nanoparticles without FA modified.The proliferation of COLO357 was significantly inhibited by FA-Chi-Gem nanoparticles.The PEG-FA-ICGDER02-Chi nanoparticles were enriched in tumor tissue in human pancreatic cancer xenografts,while non-targeted nanoparticles were mainly in normal liver tissue.PEG-FA-Gem-Chi significantly inhibited the growth of human pancreatic cancer xenografts （PEG-FA-Gem-Chi vs.Gem,t=22.950,P=0.000）.Conclusions：PEG-FA-FITC-Chi nanoparticles might be an effective targeted drug for treating human FR-positive pancreatic cancer.展开更多
Objective:To evaluate the potency of carboxymethyl chitosan-2,2' ethylenedioxy bisethylamine-folate(CMC-EDBE-FA) on tissue injury,antioxidant status and glutathione system in tissue mitochondria and serum against ...Objective:To evaluate the potency of carboxymethyl chitosan-2,2' ethylenedioxy bisethylamine-folate(CMC-EDBE-FA) on tissue injury,antioxidant status and glutathione system in tissue mitochondria and serum against nicotine-induced oxidative stress in mice.Methods: CMC-EDBE-FA was prepared on basis of carboxymethyl chitosan tagged with folic acid by covalently linkage through 2,2' ethylenedioxy bis-ethylamine.Animals were divided into four groups,i.e.,control,nicotine(1 mg/kg bw/day),CMC-EDBE-FA(1 mg/kg bw/day) and nicotine(1 mg/kg bw/day) and CMC-EDBE-FA(1 mg/kg bw/day) for 7 days.Levels of lipid peroxidation, oxidized glutathione level,antioxidant enzyme status and DNA damage were observed and compared.Results:The significantly increase of lipid peroxidation,oxidized glutathione levels and DNA damage was observed in nicotine treated group as compared with control group;those were significantly reduced in CMC-EDBE-FA supplemented group.Moreover,significantly reduced antioxidant status in nicotine treated group was effectively ameliorated by the supplementation of CMC-EDBE-FA.Only CMC-EDBE-FA treated groups showed no significant change as compared with control group;rather than it repairs the tissue damage of nicotine treated group.Conclusions:These findings suggest that CMC-EDBE-FA is non-toxic and ameliorates nicotine-induced toxicity.展开更多
This study examined associations between MTHFR C677T polymorphism and serum folate concentrations with the risk of esophageal precancerous lesions （EPL） and esophageal squamous cell carcinoma （ESCC）. The highest q...This study examined associations between MTHFR C677T polymorphism and serum folate concentrations with the risk of esophageal precancerous lesions （EPL） and esophageal squamous cell carcinoma （ESCC）. The highest quartile of serum folate concentration significantly decreased the risk of ESCC compared with the lowest quartile （0R=0.11; 95% CI, 0.04-0.33; P〈0.05）. MTHFR 677 C〉T polymorphism was associated with the risk of ESCC by using chi-square tests （P〈0.05）. For the CT genotype, the risk of ESCC significantly increased in study participants with low serum folate concentrations （〈26.92μg/L） compared with participants with high serum folate concentrations （〉26.92 μg/L） by using multinomial logistic regression models. The MTHFR genotype may further modify associations between serum folate concentrations and the risk of ESCC, but it was not significantly associated with the risk of EPL.展开更多
Colorectal cancer (CRC) is one of the most common malignancies and causes of cancer deaths throughout the world. Endoscopy has its functional and finan-cial limitations; therefore,chemoprevention might be crucial in r...Colorectal cancer (CRC) is one of the most common malignancies and causes of cancer deaths throughout the world. Endoscopy has its functional and finan-cial limitations; therefore,chemoprevention might be crucial in reducing the incidence of CRC. Although a number of studies have demonstrated the potential chemopreventive effects of folate (or folic acid),many challenges still remain. The relationship between fo-late intake and CRC risk is a complex association that might depend on many factors including gender,age,alcohol consumption,and smoking,all of which inter-fere with folate metabolism. The supplementary dose of fiber,the length of time required to observe the effects,and confounding factors exposed during the trial might also influence these findings. Therefore,more evidence from clinical studies is needed regarding the mechanisms that underlie the actions of bioactive food components in minimizing the risk of CRC.展开更多
AIM: To study the prevalence and clinical significance of hyperhomocysteinemia (hHcys), an independent factor for arterial and venous thrombosis, in a group of patients with ulcerative colitis (UC).METHODS: Fasting ho...AIM: To study the prevalence and clinical significance of hyperhomocysteinemia (hHcys), an independent factor for arterial and venous thrombosis, in a group of patients with ulcerative colitis (UC).METHODS: Fasting homocysteine (Hcys), folate, and vitamin B12 serum levels were measured in 40 UC patients and 50 healthy controls. Clinical data regarding UC were gathered.RESULTS: Median serum Hcys levels in UC patients were similar to those in controls (12.26 μmol/L vs 12.32 μmol/L), but the prevalence of hHcys was higher in UC patients than in controls (30% vs 10%, P= 0.028). UC significantly increased the risk of hHcys (adjusted odds ratio: 4.125;95% CI: 1.26-13.44). Multivariate regression analysis showed that male sex, folate and vitamin B12 deficiency or lower serum values were significant independent predictors of higher Hcys levels in UC patients (r2 = 0.4; P＜0.001).CONCLUSION: hHcys is common in UC patients and it is related to folate and vitamin B12 deficiency or lower serum values. It would be reasonable for patients with UC to receive folate and vitamin B complex supplements as a prophylactic measure.展开更多
Although methylenetetrahydrofolate reductase, a folate enzyme gene, has been associated with idiopathic male infertility, few studies have examined other folate-related metabolites and genes. We investigated whether i...Although methylenetetrahydrofolate reductase, a folate enzyme gene, has been associated with idiopathic male infertility, few studies have examined other folate-related metabolites and genes. We investigated whether idiopathic male infertility is associated with variants in folate, vitamin B12 （B12） and total homocysteine （tHcy）-related genes and measured these metabolites in blood. We conducted a case-control study that included 153 men with idiopathic infertility and 184 fertile male controls recruited at the Fertility Center and Antenatal Care Center, University Hospital, Malmo and Lund, Sweden. Serum folate, red cell folate （RCF）, serum B12, plasma tHcy and semen quality were measured. Subjects were genotyped for 20 common variants in 12 genes related to folate/B12/ homocysteine metabolism. Metabolite concentrations and genotype distributions were compared between cases and controls using linear and logistic regression with adjustment for covariates. The phosphatidylethanolamine N-methyltransferase （PEMT） M 175V and TCblR rs173665 polymorphisms were significantly associated with infertility （P=0.01 and P=0.009, respectively）, but not with semen quality. Among non-users of supplements, infertile men had lower serum folate concentrations than fertile men （12.89 vs. 14.73 nmoll^- 1 P=0.02）, but there were no significant differences in RCF, B 12 or tHcy. Folate, B 12 and tHcy concentrations were not correlated with any semen parameters. This study provides little support for low folate or B12 status in the pathogenesis of idiopathic male infertility. Although additional data are needed to confirm these initial findings, our results suggest that PEMTand TCbIR, genes involved in choline and B12 metabolism, merit further investigation in idiopathic male infertility.展开更多
Understanding the genetic mechanism underlying folate biosynthesis and accumulation in rice would be beneficial for breeding high folate content varieties as a cost-effective approach to addressing widespread folate d...Understanding the genetic mechanism underlying folate biosynthesis and accumulation in rice would be beneficial for breeding high folate content varieties as a cost-effective approach to addressing widespread folate deficiency in developing countries. In this study, the inheritance of rice grain folate content was investigated in the Lemont/Teqing recombinant inbred lines and the Koshihikari/Kasalath//Koshihikari backcross inbred lines. 264 F12 recombinant inbred lines（RILs） and 182 BC1F10 backcross inbred lines（BILs） with their parents planted in randomized complete blocks with two replicates in 2010, and RILs harvested in 2008 were used for QTL detection using inclusive composite interval mapping（ICIM） method. In the RIL population, two QTLs, denoted by qQTF-3-1 and qQTF-3-2（QTF, quantitative total folate）, explaining 7.8% and 11.1-15.8% of the folate content variation were detected in one or two years, respectively. In the BIL population, a QTL, denoted by qQTF-3-3, was detected, explaining 25.3% of the variation in folate content. All the positive alleles for higher folate content were from the high-folate parents, i.e., Teqing and Kasalath. The known putative folate biosynthesis genes do not underlie the QTLs detected in this study and therefore may be novel loci affecting folate content in milled rice. QTLs identified in this study have potential value for marker assisted breeding for high-folate rice variety.展开更多
文摘Dihydrofolate reductase (DHFR) is an enzyme that catalyzes the reduction of dihydrofolate (DHF) to tetrahydrofolate (THF). Chemotherapy drugs such as methotrexate help to slow the progression of cancer by limiting the ability of dividing cells to make nucleotides by competitively inhibiting DHFR. Nonsteroidal anti-inflammatory drugs (NSAIDs) have been previously reported to exhibit competitive inhibition of DHFR, in addition to their primary action on cyclooxygenase enzymes. This interaction interferes with the enzymatic reduction of dihydrofolate to tetrahydrofolate, thereby impeding the folate metabolism pathway essential for nucleotide synthesis and cell proliferation. This activity stems from their structural resemblance to the p-aminobenzoyl-l-glutamate (pABG) moiety of folate, a substrate of DHFR. It has been established that NSAIDs containing a salicylate group (which has structural similarities to pABG), such as diflunisal, exhibit stronger DHFR-binding activity. In this study, we synthesized salicylate derivatives of naproxen with the aim of exploring their potential as inhibitors of DHFR. The interactions between these derivatives and human DHFR were characterized using a combination of biochemical, biophysical, and structural methods. Through polyacrylamide gel electrophoresis (PAGE) analysis, enzymatic assays, and quantitative ELISA, we investigated the binding affinity and inhibitory potency of the synthesized salicylate derivatives towards DHFR. The findings of this study suggest the potential of salicylate derivatives of naproxen as promising candidates for the inhibition of DHFR, thereby offering novel therapeutic opportunities for modulating the inflammatory process through multiple pathways. Further optimization of these derivatives could lead to the development of more efficacious dual-targeted analogs with enhanced therapeutic benefits.
基金supported by the National Health Commission of the People’s Republic of China Medical Reform Major Program:China National Chronic Diseases and Nutrition Surveillance of Adults[2015-2017]Qianrang Zhu is funded by a China Scholarship Council PhD Scholarship[No.202109110099].
文摘Objective This study aimed to evaluate the associations of serum folate and/or vitamin B12 concentrations with obesity among Chinese children and adolescents.Methods A cross-sectional study was conducted including 3,079 Chinese children and adolescents,aged 6 to 17 years,from Jiangsu,China.Anthropometric indices,such as,children's body mass index(BMI),BMI z-scores,waist circumference,and waist-to-height ratio were utilized.Multivariable linear regression and generalized additive models were used to investigate the associations of serum folate and vitamin B12 levels with anthropometric indices and odds of obesity.Results We observed that serum vitamin B12 concentrations were inversely associated with all anthropometric indices and the odds of general obesity[odds ratio(OR)=0.68;95%confidence interval(CI)=0.59,0.78]and abdominal obesity(OR=0.68;95%CI=0.60,0.77).When compared to participants with both serum vitamin levels in the two middle quartiles,those with both serum folate and vitamin B12 levels in the highest quartile were less prone to general(OR=0.31,95%CI=0.19,0.50)or abdominal obesity(OR=0.46,95%CI=0.31,0.67).Conversely,participants with vitamin B12 levels in the lowest quartile alongside folate levels in the highest quartile had higher odds of abdominal obesity(OR=2.06,95%CI=1.09,3.91).Conclusion Higher serum vitamin B12 concentrations,but not serum folate concentrations,were associated with lower odds of childhood obesity.Children and adolescents with high levels of vitamin B12 and folate were less likely to be obese.
基金supported by the National Natural Sciences [82071690,81971390]Research Foundation of Capital Institute of Pediatrics [FX-2020-05,CXYJ-2-21-09]+1 种基金Public service development and reform pilot project of Beijing Medical Research Institute [BMR2021-1]Beijing Hospitals Authority Clinical technology innovation program [XLMX 202110]。
文摘Objective Circular RNAs(circRNAs)participate in several important pathological processes and have been used in the diagnosis and treatment of various diseases.This study aimed to investigate the role of circRNAs in neural tube defects(NTDs).Method We characterized circRNA-associated competitive endogenous RNA(ceRNA)networks in brain tissue of low folate-induced NTDs mouse at embryonic day 13.5 by high-throughput sequencing.The expression levels of Circzfp644,miR-20-5p and Gas7 were detected by RT-PCR.Gas7 and Circzfp644functions were determined by miRNA-mimics and inhibitors in mouse teratocarcinoma cells(F9 cells),and luciferase gene reporter assay was assessed in the F9 cells.In addition,the expression levels of Circzfp644,miR-20-5p and Gas7 were determined by Nanostring in human NTDs tissues.Results We detected 57 circRNA transcripts,16 miRNAs,and 148 mRNAs that were significantly dysregulated in NTDs brain tissues compared with their expression levels in control(normal)tissues.Circzfp644 shared miRNA response elements with the growth arrest specific 7(Gas7)gene and competitively bound with miR-20-5p to increase the expression of Gas7.Downregulation of Circzfp644and Gas7 and upregulation of miR-20-5p were found in human NTD tissue.Conclusion This study provides new perspectives on the role of circRNAs in nervous system development and the pathogenesis of NTDs.
基金The office of the Vice Chancellor for Research, Shiraz University of Medical Sciences, No. 83-2212 Grant from the Gastroenterohepatology Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran
文摘AIM:To evaluate joint effects of Methylentetra-hydrofolate reductase(MTHFR) C677T genotypes,and serum folate/vitamin B12 concentrations on promoter methylation of tumor-associated genes among Iranian colorectal cancer patients. METHODS:We examined the associations between MTHFR C677T genotype,and promoter methylation of P16,hMLH1,and hMSH2 tumor-related genes among151 sporadic colorectal cancer patients. The promoter methylation of tumor-related genes was determined by methylation-specific PCR. Eighty six patients from whom fresh tumor samples were obtained and 81 controls were also examined for serum folate and vitamin B12 concentrations by a commercial radioimmunoassay kit. RESULTS:We found 29.1% of cases had tumors with at least one methylated gene promoter. In case-case comparison,we did not find a significant association between methylation in tumors and any single genotype. However,in comparison to controls with the CC genotype,an increased risk of tumor methylation was associated with the CT genotype(OR = 2.5;95% CI,1.1-5.6) . In case-case comparisons,folate/vitamin B12 levels were positively associated with tumor methylation. Adjusted odds ratios for tumor methylation in cases with high(above median) versus low(below median) serum folate/vitamin B12 levels were 4.9(95% CI,1.4-17.7) ,and 3.9(95% CI,1.1-13.9) ,respectively. The frequency of methylated tumors was significantly higher in high methyl donor than low methyl donor group,especially in those with MTHFR CT(P = 0.01) ,and CT/TT(P = 0.002) genotypes,but not in those with the CC genotype(P = 1.0) . CONCLUSION:We conclude that high concentrations of serum folate/vitamin B12 levels are associated with the risk of promoter methylation in tumor-specific genes,and this relationship is modified by MTHFR C677T genotypes.
基金Supported by the National Basic Research Funds of China 973 Project, No. 2005CB522400 grants from the National Natural Science Foundation of China, No. 30470781 grants from Shanghai Municipal Commission for Science and Technology, No. 04DZ14006 and Doctoral Funds from the Ministry of Education of China, No. 20050266013
文摘AIM: To evaluate whether folate levels in mucosal tissue and some common methylenetetrahydrofolate reductase (MTHFR) variants are associated with the risk of gastric cancer through DNA methylation. METHODS: Real-time PCR was used to study the expression of tumor related genes in 76 mucosal tissue samples from 38 patients with gastric cancer. Samples from the gastroscopic biopsy tissues of 34 patients with chronic superficial gastritis (CSG) were used as controls. Folate concentrations in these tissues were detected by the FOL ACS: 180 automated chemiluminescence system. MTHFR polymorphisms were analyzed by PCR-RFLP, and the promoter methylation of tumor-related genes was determined by methylation-specific PCR (MSP). RESULTS: Folate concentrations were significantly higher in CSG than in cancerous tissues. Decreased expression and methylation of c-myc accompanied higher folate concentrations. Promoter hypermethylation and loss of p16INK4A in samples with MTHFR 677CC were more frequent than in samples with the 677TT or 677CT genotype. And the promoter hypermethylation and loss of p21WAF1 in samples with MTHFR 677CT were more frequent than when 677CC or 677TT was present. The 677CT genotype showed a non-significant higher risk for gastric cancer as compared with the 677CC genotype. CONCLUSION: Lower folate levels in gastric mucosal tissue may confer a higher risk of gastric carcinogenesisthrough hypomethylation and overexpression of c-myc.
基金supported by the National Natural Science Foundation of China under the Grant No. 81973048a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, Culture, Sports and Technology of Japan [JSPS-C-21580137]。
文摘Objective This study aimed to investigate the effects of N,N-dimethylglycine(DMG) on the concentration and metabolism of plasma homocysteine(pHcy) in folate-sufficient and folate-deficient rats.Methods In this study, 0.1% DMG was supplemented in 20% casein diets that were either folatesufficient(20 C) or folate-deficient(20 CFD). Blood and liver of rats were subjected to assays of Hcy and its metabolites. Hcy and its related metabolite concentrations were determined using a liquid chromatographic system.Results Folate deprivation significantly increased pHcy concentration in rats fed 20 C diet(from 14.19 ±0.39 μmol/L to 28.49 ± 0.50 μmol/L;P < 0.05). When supplemented with DMG, pHcy concentration was significantly decreased(12.23 ± 0.18 μmol/L) in rats fed 20 C diet but significantly increased(31.56 ±0.59 μmol/L) in rats fed 20 CFD. The hepatic methionine synthase activity in the 20 CFD group was significantly lower than that in the 20 C group;enzyme activity was unaffected by DMG supplementation regardless of folate sufficiency. The activity of hepatic cystathionine β-synthase(CBS) in the 20 CFD group was decreased but not in the 20 C group;DMG supplementation enhanced hepatic CBS activity in both groups, in which the effect was significant in the 20 C group but not in the other group.Conclusion DMG supplementation exhibited hypohomocysteinemic effects under folate-sufficient conditions. By contrast, the combination of folate deficiency and DMG supplementation has deleterious effect on pHcy concentration.
文摘The Egyptian government introduced wheat-flour fortification with iron and folic acid to reduce the incidence of neural tube defects, but suspended it for technical reasons. We previously developed novel legume foods with enhanced folate content. In this study, we investigated the efficacy of 12-week intervention with folate-enhanced foods versus folic acid supplement in improving folate status in Egyptian women. A randomized, parallel intervention trial with two active groups (n = 19, n = 18) and one blinded control group (n = 20) was executed over 12 weeks. Volunteers received either germinated legume foods and orange juice (≈250 μg/d folate) or folic acid supplement (500 μg/d) or apple juice (0 μg/d folate). Folate status was assessed by erythrocyte and plasma folate and total homocysteine (tHcy) at day 0, and after 8 and 12 weeks of intervention. After 12 weeks, mean plasma folate increased by 14 (P < 0.0001) and 12 (P < 0.0001) nmoL in the folic acid and food group, respectively. Erythrocyte folate concentration increased in the folic acid group from 614 to 912 (P < 0.0001) and in the food group from 631 to 914 nmoL (P < 0.0001). After 12 weeks, 90% of subjects in the folic acid group and 70% in the food group had erythrocyte folate concentrations exceeding 906 nmol/L. tHcy concentration was decreased by 20% (P = 0.007) and 18% (P = 0.006) in the folic acid and food group, respectively, but remained unchanged in the control group during intervention. Folate-enhanced foods effectively improve folate status in women of reproductive age. These foods could be used as a complement to folic acid fortification.
文摘Methylenetetrahydrofolate reductase(MTHFR)is a key enzyme for the critical process of one-carbon circulation,which convert5,10-methylenetetrahydrofolate to5-methyltetrahydrofolate and participate in folate and homocysteine conversion correlated to methyl group supply.The enzyme activity decline depends on the gene polymorphism.MTHFR impacts on the methylation process which is related to psychiatric diseases.Studies have shown association between MTHFR gene polymorphisms and mental disorders,some of which stratified by folate and cobalamin levels.In this review,we will summarize the testimony on the relationship between methylation and MTHFR polymorphism as well as the implication on psychiatric diseases by MTHFR mutation.
文摘Objective To review the association of methylene tetrahydrofolate reductase (MTHFR) C677T mutant with coronary artery disease, as well as to highlight the results of some of these studies and to emphasize the need to focus on the genetic architecture of CAD. Data SourcesData used in this article is mainly from relevant articles obtained through Pubmed, OVID and Google Scholar published from 1980 to 2008. Major studies and trials in this period were taken into account to draw accurate conclusion on the relation of those mutations in MTHFR with homocysteinemia and CAD. ResultOur analysis shows that hyperhomocysteinemia, a risk factor for occlusive arterial diseases, can be caused by disruptions of homocysteine metabolism catalyzed by MFTHR. A common alanine to valine mutation in MTHFR may contribute to mild heperhomocysteinemia in CAD. Individuals with the homozygous mutant genotype had higher plasma homocysteine, particularly when plasma folate was below the median value. ConclusionThis MTHFR mutant in the setting of insufficient folate may be a risk factor of CAD and can be regarded as a model of genetic-environmental interaction in the development of CAD.
基金Project (No. 2003ABA148) supported by the Science Foundation of Hubei Province, China
文摘Objective: To explore the relationship between genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), the central enzymes in folate metabolism that affects DNA methylation and synthesis, and the risk of Down syndrome in China. Methods: Genomic DNA was isolated from the peripheral lymphocytes of 64 mothers of children with Down syndrome and 70 age matched control subjects. Polymerase chain reaction and restriction fragment length polymorphism were used to examine the polymorphisms of MTHFR 677C→T, MTRR 66A→G and the relationship between these genotypes and the risk of Down syndrome was analyzed. Results: The results show that the MTHFR 677C→T polymorphism is more prevalent among mothers of children with Down syndrome than among control mothers, with an odds ratio of 3.78 (95% confidence interval (CI), 1.78～8.47). In addition, the homozygous MTRR 66A→G polymorphism was independently associated with a 5.2-fold increase in estimated risk (95% CI, 1.90～14.22). The combined presence of both polymorphisms was associated with a greater risk of Down syndrome than the presence of either alone, with an odds ratio of 6.0 (95% CI, 2.058～17.496). The two polymorphisms appear to act without a multiplicative interaction. Conclusion: MTHFR and MTRR gene mutation alleles are related to Down syndrome, and CT, TT and GG gene mutation types increase the risk of Down syndrome.
基金Supported by National Science Council,Executive YuanNo.NSC-96-2314-B-075A-007,No.NSC100-2628-B005002MY4,No.NSC101-2320-B-005-006-MY3 and No.NSC101-2911-I-005-301the ATU plan of the Ministry of Education,Taiwan
文摘AIM: To evaluate the associations of serum folate levelwith development, invasiveness and patient survival of gastric cancer. METHODS: In this nested case-control study, patients with newly diagnosed gastric cancer undergoing gastrectomy were enrolled, and patients receiving chemotherapy prior to surgery, with other concurrent malignancy, or of the aboriginal and alien populations were excluded. In total, 155 gastric cancer patients and 149 healthy controls were enrolled for determination of serum folate levels and their correlation with gastric cancer. Using the median value of serum folate computed among the overall population as the cutoff value, the associations between serum folate and gastric cancer in all cases and different age and gender subgroups were analyzed by multivariate logistic regression analysis. In the patient cohort of gastric cancer, receiver-operating characteristic analyses were performed to calculate the best cutoff values of serum folate, and the associations between serum folate levels and clinicopathological features were further analyzed by multivariate regression analysis. Survival analyses were conducted using the Cox proportional hazards model.RESULTS: The mean serum folate level was significantly lower in gastric cancer patients than that in controls(3.71 ± 0.30 ng/mL vs 8.00 ± 0.54 ng/mL, P < 0.01), and folate levels were consistently lower in gastric cancer patients regardless of age and gender(all P < 0.01). Using the median serum folate value as the cutoff value, low serum folate was significantly associated with gastric cancer risk in the whole population(OR = 19.77, 95%CI: 10.54-37.06, P < 0.001) and all strata(age < 60 years OR = 17.39, 95%CI: 7.28-41.54, age ≥ 60 years(OR = 21.67, 95%CI: 8.27-56.80), males(OR = 17.95, 95%CI: 7.93-40.62), and females(OR = 20.95, 95%CI: 7.66-57.31); all P < 0.001. In the patient cohort of gastric cancer, the respective cutoff values showed that low serum folate levels were significantly associated with serosal invasion(OR = 2.54, 95%CI: 1.23-5.23), lymphatic invasion(OR = 2.23, 95%CI: 1.17-4.26), and liver metastasis(OR =6.67, 95%CI: 1.28-34.91) of gastric cancer(all P < 0.05). Serum folate level below 1.90 ng/mL was associated with poor patient survival(HR = 1.84, 95%CI: 1.04-3.27, P < 0.05) in univariate analysis.CONCLUSION: Lower serum folate levels were significantly associated with gastric cancer development and invasive phenotypes. The role of folate depletion in gastric cancer invasion warrants further study.
基金supported by a grant 30872999 from the National Natural Science Foundation of Chinaa grant BK2007023 from Jiangsu Province Natural Science Foundation of China
文摘Objective： Nanoparticles are becoming an important method of targeted drug delivery. To evaluate the importance of folate-conjugated human serum albumin （HSA） magnetic nanoparticles （Folate-CDDP/HSA MNP）, we prepared drug-loaded Folate-CDDP/HSA MNPs and characterized their features. Methods： First, folate was conjugated with HSA under the effect of a condensing agent, and the conjugating rate was evaluated by a colorimetric method using 2, 4, 6 - trinitrobenzene sulfonic acid. Second, under N., gas, Fe：~O1 magnetic nanomaterials were prepared and characterized by using transmission electron microscopy （TEM）, SEM-EDS and X-ray diffraction （XRD）. Finally, Folate-CDDP/HSA MNP was prepared by using a solvent evaporation technique. TEM was used to observe particle morphology. The particle size and distribution of the prepared complexes were determined by a Laser particle size analyzer. Drug loading volume and drug release were investigated by a high performance liquid chromatography method （HPLC） in vitro. Results： We successfully prepared folate-conjugated HSA and its conjugating rate was 27.26 μg/mg. Under TEM, Fe2O4 magnetic nanoparticles were highly electron density and had an even size distribution in the range of 10-20 nm. It was confirmed by SEM-EDS and XRD that Fe304 magnetic nanoparticles had been successfully prepared. Under TEM, drug-loaded magnetic nanoparticles were observed, which had a round shape, similar uniform size and smooth surface. Their average size was 79 nm which was determined by laser scattering, and they exhibited magnetic responsiveness. Encapsulation efficiency was 89.75% and effective drug loading was calculated to be 15.25%. The release results in vitro showed that the half release time （ta/2） of cisplatin in cisplatin Solution and Folate-CDDP/HSA MNP was 65 min and 24 h respectively, which indicated that microspheres had an obvious effect of sustained-release. Conclusion： Folate-CDDP/HSA MNPs were prepared successfully. The preparation process and related characteristics data provided a foundation for further study, including the mechanism of the nanoparticles distribution in vivo and their intake by tumor cells.
基金supported by the National Natural Science Foundation of China(No.81071967 and 30872500)the Natural Science Foundation of Jiangsu province(Project No:BK2010242)
文摘Objective：Human pancreatic cancer is one of the most common clinical malignancies.The effect of comprehensive treatment based on surgery is general.The effects of chemotherapy were not obvious mainly because of lack of targeting and chemoresistance in pancreatic cancer.This study aimed to investigate the effects of folate receptor （FR）-mediated gemcitabine FA-Chi-Gem nanoparticles with a core-shell structure by electrostatic spray on pancreatic cancer.Methods：In this study,the levels of expression of FR in six human pancreatic cancer cell lines were studied by immunohistochemical analysis.The uptake rate of isothiocyanate-labeled FA-Chi nanoparticles in FR high expression cell line COLO357 was assessed by fluorescence microscope and the inhibition rate of FA-Chi-Gem nanoparticles on COLO357 cells was evaluated by MTT assay.Moreover,the biodistribution of PEG-FA-ICGDER02-Chi in the orthotopic pancreatic tumor model was observed using near-infrared imaging and the human pancreatic cancer orthotopic xenografts were treated with different nanoparticles and normal saline control.Results：The expression of FR in COLO357 was the highest among the six pancreatic cancer cell lines.The FR mainly distributed on cell membrane and fewer in the cytoplasm in pancreatic cancer.Moreover,the absorption rate of the FA-Chi-Gem nanoparticles was more than the Chi nanoparticles without FA modified.The proliferation of COLO357 was significantly inhibited by FA-Chi-Gem nanoparticles.The PEG-FA-ICGDER02-Chi nanoparticles were enriched in tumor tissue in human pancreatic cancer xenografts,while non-targeted nanoparticles were mainly in normal liver tissue.PEG-FA-Gem-Chi significantly inhibited the growth of human pancreatic cancer xenografts （PEG-FA-Gem-Chi vs.Gem,t=22.950,P=0.000）.Conclusions：PEG-FA-FITC-Chi nanoparticles might be an effective targeted drug for treating human FR-positive pancreatic cancer.
文摘Objective:To evaluate the potency of carboxymethyl chitosan-2,2' ethylenedioxy bisethylamine-folate(CMC-EDBE-FA) on tissue injury,antioxidant status and glutathione system in tissue mitochondria and serum against nicotine-induced oxidative stress in mice.Methods: CMC-EDBE-FA was prepared on basis of carboxymethyl chitosan tagged with folic acid by covalently linkage through 2,2' ethylenedioxy bis-ethylamine.Animals were divided into four groups,i.e.,control,nicotine(1 mg/kg bw/day),CMC-EDBE-FA(1 mg/kg bw/day) and nicotine(1 mg/kg bw/day) and CMC-EDBE-FA(1 mg/kg bw/day) for 7 days.Levels of lipid peroxidation, oxidized glutathione level,antioxidant enzyme status and DNA damage were observed and compared.Results:The significantly increase of lipid peroxidation,oxidized glutathione levels and DNA damage was observed in nicotine treated group as compared with control group;those were significantly reduced in CMC-EDBE-FA supplemented group.Moreover,significantly reduced antioxidant status in nicotine treated group was effectively ameliorated by the supplementation of CMC-EDBE-FA.Only CMC-EDBE-FA treated groups showed no significant change as compared with control group;rather than it repairs the tissue damage of nicotine treated group.Conclusions:These findings suggest that CMC-EDBE-FA is non-toxic and ameliorates nicotine-induced toxicity.
基金supported by grants from the National Science Foundation of China(No.30800914 and No.81372985)Dietary Nutrition Research and Education Foundation of Danone(DIC2011-05)Program Granted for Scientific Innovation Research of College Graduate in Jiangsu Province Research Fund(CXZZ_0179)
文摘This study examined associations between MTHFR C677T polymorphism and serum folate concentrations with the risk of esophageal precancerous lesions （EPL） and esophageal squamous cell carcinoma （ESCC）. The highest quartile of serum folate concentration significantly decreased the risk of ESCC compared with the lowest quartile （0R=0.11; 95% CI, 0.04-0.33; P〈0.05）. MTHFR 677 C〉T polymorphism was associated with the risk of ESCC by using chi-square tests （P〈0.05）. For the CT genotype, the risk of ESCC significantly increased in study participants with low serum folate concentrations （〈26.92μg/L） compared with participants with high serum folate concentrations （〉26.92 μg/L） by using multinomial logistic regression models. The MTHFR genotype may further modify associations between serum folate concentrations and the risk of ESCC, but it was not significantly associated with the risk of EPL.
基金Supported by Grant from the Ministry of Public Health, China, No. 200802094
文摘Colorectal cancer (CRC) is one of the most common malignancies and causes of cancer deaths throughout the world. Endoscopy has its functional and finan-cial limitations; therefore,chemoprevention might be crucial in reducing the incidence of CRC. Although a number of studies have demonstrated the potential chemopreventive effects of folate (or folic acid),many challenges still remain. The relationship between fo-late intake and CRC risk is a complex association that might depend on many factors including gender,age,alcohol consumption,and smoking,all of which inter-fere with folate metabolism. The supplementary dose of fiber,the length of time required to observe the effects,and confounding factors exposed during the trial might also influence these findings. Therefore,more evidence from clinical studies is needed regarding the mechanisms that underlie the actions of bioactive food components in minimizing the risk of CRC.
文摘AIM: To study the prevalence and clinical significance of hyperhomocysteinemia (hHcys), an independent factor for arterial and venous thrombosis, in a group of patients with ulcerative colitis (UC).METHODS: Fasting homocysteine (Hcys), folate, and vitamin B12 serum levels were measured in 40 UC patients and 50 healthy controls. Clinical data regarding UC were gathered.RESULTS: Median serum Hcys levels in UC patients were similar to those in controls (12.26 μmol/L vs 12.32 μmol/L), but the prevalence of hHcys was higher in UC patients than in controls (30% vs 10%, P= 0.028). UC significantly increased the risk of hHcys (adjusted odds ratio: 4.125;95% CI: 1.26-13.44). Multivariate regression analysis showed that male sex, folate and vitamin B12 deficiency or lower serum values were significant independent predictors of higher Hcys levels in UC patients (r2 = 0.4; P＜0.001).CONCLUSION: hHcys is common in UC patients and it is related to folate and vitamin B12 deficiency or lower serum values. It would be reasonable for patients with UC to receive folate and vitamin B complex supplements as a prophylactic measure.
文摘Although methylenetetrahydrofolate reductase, a folate enzyme gene, has been associated with idiopathic male infertility, few studies have examined other folate-related metabolites and genes. We investigated whether idiopathic male infertility is associated with variants in folate, vitamin B12 （B12） and total homocysteine （tHcy）-related genes and measured these metabolites in blood. We conducted a case-control study that included 153 men with idiopathic infertility and 184 fertile male controls recruited at the Fertility Center and Antenatal Care Center, University Hospital, Malmo and Lund, Sweden. Serum folate, red cell folate （RCF）, serum B12, plasma tHcy and semen quality were measured. Subjects were genotyped for 20 common variants in 12 genes related to folate/B12/ homocysteine metabolism. Metabolite concentrations and genotype distributions were compared between cases and controls using linear and logistic regression with adjustment for covariates. The phosphatidylethanolamine N-methyltransferase （PEMT） M 175V and TCblR rs173665 polymorphisms were significantly associated with infertility （P=0.01 and P=0.009, respectively）, but not with semen quality. Among non-users of supplements, infertile men had lower serum folate concentrations than fertile men （12.89 vs. 14.73 nmoll^- 1 P=0.02）, but there were no significant differences in RCF, B 12 or tHcy. Folate, B 12 and tHcy concentrations were not correlated with any semen parameters. This study provides little support for low folate or B12 status in the pathogenesis of idiopathic male infertility. Although additional data are needed to confirm these initial findings, our results suggest that PEMTand TCbIR, genes involved in choline and B12 metabolism, merit further investigation in idiopathic male infertility.
基金supported by grants from the National Basic Research Program of China(2007CB10880-1,2013CB127000)
文摘Understanding the genetic mechanism underlying folate biosynthesis and accumulation in rice would be beneficial for breeding high folate content varieties as a cost-effective approach to addressing widespread folate deficiency in developing countries. In this study, the inheritance of rice grain folate content was investigated in the Lemont/Teqing recombinant inbred lines and the Koshihikari/Kasalath//Koshihikari backcross inbred lines. 264 F12 recombinant inbred lines（RILs） and 182 BC1F10 backcross inbred lines（BILs） with their parents planted in randomized complete blocks with two replicates in 2010, and RILs harvested in 2008 were used for QTL detection using inclusive composite interval mapping（ICIM） method. In the RIL population, two QTLs, denoted by qQTF-3-1 and qQTF-3-2（QTF, quantitative total folate）, explaining 7.8% and 11.1-15.8% of the folate content variation were detected in one or two years, respectively. In the BIL population, a QTL, denoted by qQTF-3-3, was detected, explaining 25.3% of the variation in folate content. All the positive alleles for higher folate content were from the high-folate parents, i.e., Teqing and Kasalath. The known putative folate biosynthesis genes do not underlie the QTLs detected in this study and therefore may be novel loci affecting folate content in milled rice. QTLs identified in this study have potential value for marker assisted breeding for high-folate rice variety.
