Higher Folate Levels Research Articles

Maternal Serum Folate During Pregnancy and Congenital Heart Disease in Offspring

The association of folate supplementation with congenital heart disease (CHD) prevention is controversial. To examine the association of maternal serum folate levels at early to midpregnancy with CHD risk in offspring. This case-control study recruited participants from one of China's largest cardiac referral centers between 2015 and 2018. CHD cases and non-CHD controls were matched according to maternal age at a ratio of 1:4. Data were analyzed from May to August 2023. Maternal serum levels of folate, vitamin B12, and homocysteine were measured around the gestational age of 16 weeks. The primary outcome was CHD, which was confirmed using echocardiography. The association between CHD risk in offspring with maternal folate levels was measured using adjusted odds ratios (aORs) with 95% CIs in conditional logistic regression analyses. Interactions between folate, vitamin B12, and homocysteine and CHD were estimated on a multiplicative scale. A total of 129 CHD cases with ventricular septal defect as the most common phenotype and 516 matched controls were included. The mean (SD) maternal age at pregnancy was 31.6 (5.3) years. There was a U-shaped association between maternal serum folate levels at early to midpregnancy and CHD risk in offspring. Compared with the offspring in the second and third quartiles of maternal folate, those in the lowest (aOR, 3.09; 95% CI, 1.88-5.08) and highest quartiles (OR, 1.81; 95% CI, 1.07-3.06) had increased odds of CHD. The ORs were higher when applying the World Health Organization criteria to determine the normal range for serum folate levels. Interaction analyses suggested that the adverse associations between low and high maternal folate and CHD risk might be further magnified by vitamin B12 deficiency or elevated homocysteine. In this case-control study of CHD, low maternal serum folate levels in early to midpregnancy were associated with an increased CHD risk in offspring, and excessively high folate levels were also associated with an elevated CHD risk. Further investigation is needed to make causal inferences for the observed associations and elucidate the underlying mechanisms.

Folate, Homocysteine, and Adverse Outcomes After Ischemic Stroke.

As a risk factor of cardiovascular diseases, homocysteine can be effectively lowered by folate. However, the associations of folate and homocysteine levels with the prognosis of ischemic stroke remained unclear. A total of 3530 patients with ischemic stroke were included. Serum folate and homocysteine levels were measured at admission. The primary outcome was composite of death and major disability (modified Rankin Scale score≥3) at 3 months after stroke onset. Univariate and multivariate logistic regression models were used. The mediation effect of homocysteine was examined. During follow-up, 1056 participants developed the primary outcome. In the univariate model, participants in the highest quartile of folate had a 29% (95% CI, 0.58-0.87) decreased risk of primary outcome compared with those in the lowest quartile. After multivariate adjustment, the odds ratio associated with the highest quartile of folate was 0.58 (95% CI, 0.46-0.73) for primary outcome. In contrast, participants in the highest quartile of homocysteine had a 52% (95% CI, 1.24-1.98) increased risk of primary outcome compared with those in the lowest quartile. After multivariate adjustment, the odds ratio associated with highest quartile of homocysteine was 1.57 (95% CI, 1.24-1.98) for primary outcome. In addition, 25.5% of the observed associations between folate and primary outcome was mediated through homocysteine (P=0.012). High folate levels were associated with low risks of death and major disability among Chinese patients with ischemic stroke, and homocysteine partially mediated the observed potential beneficial role of folate.

Dual folate/biotin-decorated liposomes mediated delivery of methylnaphthazarin for anti-cancer activity

Chemotherapy is an effective strategy for mitigating the global challenge of cancer treatment, which often encounters drug resistance and negative side effects. Methylnaphthazarin (MNZ), a natural compound with promising anti-cancer properties, has been underexplored due to its poor aqueous solubility and low selectivity. This study introduces a novel approach to overcome these limitations by developing MNZ-encapsulating liposomes decorated with folate and biotin (F/B-LP-MNZ). This dual-targeting strategy aims to enhance the anti-cancer efficacy and specificity of MNZ delivery. Our innovative F/B-LP-MNZ formulation demonstrated excellent physicochemical properties, stability, and controlled drug release profiles. In vitro studies revealed that MNZ-loaded liposomes attenuate the toxicity associated with free MNZ while F/B-LP-MNZ significantly increased cytotoxicity against HeLa cells, which express high levels of folate and biotin receptors, compared to non-targeted liposomes. Enhanced cellular uptake and improved dynamic flow attachment further confirmed the superior specificity of F/B-LP in targeting cancer cells. Additionally, our results revealed that F/B-LP-MNZ effectively inhibits HeLa cell migration and adhesion through EMT suppression and apoptotic induction, indicating its potential to prevent cancer metastasis. These findings highlight the potential of dual folate and biotin receptors-targeting liposomes as an effective delivery system for MNZ, offering a promising new avenue for targeted cancer therapy.

The impact of folic acid/VB12 deficiency on essential hypertension in children and adolescents: from a nested case-control and a cohort study.

To explore the relationship between serum folic acid (FA) or Vitamin B12 (VB12) and elevated BP in children and adolescents. Both a nested case control and a cohort study were designed to explore the relationship between serum folic acid (FA) or Vitamin B12 (VB12) and elevated blood pressure (BP). All the included participants were from primary school. A total of 326 subjects (116:210) in nested case control were from an established cohort. And 270 participants without hypertension at baseline and followed in 2019 in cohort. FA and VB12 levels were lower in the elevated BP group than in the control group, and homocysteine level was higher than that in the control group. In the elevated BP group, overweight/obese children had lower FA than overweight/obese children in the normal BP group. FA was positively correlated with high-density lipoprotein (HDL) and Apo lipoprotein A (APOA), but negatively correlated with triglyceride (TG). FA was significantly correlated with elevated BP in children and adolescents (β = -0.353, P = 0.032), after adjusting VB12, and homocysteine (HCY), and the interaction effect of FA*HCY was significant. Both systolic and diastolic BP levels were statistically lower in the FA high exposure group than in the FA low exposure group in the cohort study. This study found that FA and vitamin B12 deficiency in childhood was correlated with elevated BP levels, which may affect BP by regulating lipid levels, and confirmed the importance of maintaining high levels of FA and vitamin B12 in childhood either by diet or supplementation.

Red blood cell folate level is associated with periodontitis in American adults: results from the NHANES 2009–2014

BackgroundRed blood cell (RBC) folate is an indicator of long-term folate nutrition. Whether there is an association between RBC folate and periodontitis is unclear. This study aimed to use the NHANES database to determine whether RBC folate is associated with moderate/severe periodontitis.MethodsA cross-sectional analysis of 10,151 participants in the NHANES database from 2009 to 2014 was performed. Multivariate logistic regression was used to analyze the independent relationship between RBC folate and moderate/severe periodontitis. The generalized additive model (GAM), restricted cubic splines (RCS), smooth curve fitting, and threshold effect analysis were used to explore the dose–response relationship and the potential nonlinear relationship between RBC folate and periodontitis. Finally, subgroup analysis and interaction tests were performed to determine the effect of covariates on the relationship between RBC folate and moderate/severe periodontitis.ResultsAfter adjusting for all confounders, there was a negative association between RBC folate concentration and moderate/severe periodontitis. The lowest fraction Q1 (< 360 ng/mL) of RBC folate concentration was used as the reference group, multivariable-adjusted ORs and 95% CIs of the second (360-463 ng/mL), third (464-569 ng/mL), fourth (570-732 ng/mL), and the highest quintile (> 733 ng/mL) categories were 0.88 (0.77, 1.01), 0.83 (0.72, 0.96), 0.77 (0.67, 0.90), 0.65 (0.56, 0.77) respectively. Additionally, a threshold nonlinear association was found between RBC folate (ng/mL) log2 transformation and moderate/severe periodontitis.ConclusionThis cross-sectional study revealed a negative relationship between RBC folate and moderate/severe periodontitis within a certain threshold range. Dentists and policymakers should pay closer attention to oral hygiene and health care for people with low or high RBC folate levels. Further causal and longitudinal research mechanisms are needed to validate our findings.

Association of Serum Folate and Vitamin B12 Concentrations with Obesity in Chinese Children and Adolescents*

ObjectiveThis study aimed to evaluate the associations of serum folate and/or vitamin B12 concentrations with obesity among Chinese children and adolescents. MethodsA 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. ResultsWe 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). ConclusionHigher 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.

A new physiological medium uncovers biochemical and cellular alterations in Lesch-Nyhan disease fibroblasts

BackgroundLesch-Nyhan disease (LND) is a severe neurological disorder caused by the genetic deficiency of hypoxanthine–guanine phosphoribosyltransferase (HGprt), an enzyme involved in the salvage synthesis of purines. To compensate this deficiency, there is an acceleration of the de novo purine biosynthetic pathway. Most studies have failed to find any consistent abnormalities of purine nucleotides in cultured cells obtained from the patients. Recently, it has been shown that 5-aminoimidazole-4-carboxamide riboside 5ʹ-monophosphate (ZMP), an intermediate of the de novo pathway, accumulates in LND fibroblasts maintained with RPMI containing physiological levels (25 nM) of folic acid (FA), which strongly differs from FA levels of regular cell culture media (2200 nM). However, RPMI and other standard media contain non-physiological levels of many nutrients, having a great impact in cell metabolism that does not precisely recapitulate the in vivo behavior of cells.MethodsWe prepared a new culture medium containing physiological levels of all nutrients, including vitamins (Plasmax-PV), to study the potential alterations of LND fibroblasts that may have been masked by the usage of non-physiological media. We quantified ZMP accumulation under different culture conditions and evaluated the activity of two known ZMP-target proteins (AMPK and ADSL), the mRNA expression of the folate carrier SLC19A1, possible mitochondrial alterations and functional consequences in LND fibroblasts.ResultsLND fibroblasts maintained with Plasmax-PV show metabolic adaptations such a higher glycolytic capacity, increased expression of the folate carrier SCL19A1, and functional alterations such a decreased mitochondrial potential and reduced cell migration compared to controls. These alterations can be reverted with high levels of folic acid, suggesting that folic acid supplements might be a potential treatment for LND.ConclusionsA complete physiological cell culture medium reveals new alterations in Lesch-Nyhan disease. This work emphasizes the importance of using physiological cell culture conditions when studying a metabolic disorder.

Association Between High Blood Folate Levels and Glaucoma in a Representative Korean Population.

This study aimed to investigate the association between folate levels and the prevalence of glaucoma. This nationwide population-based cross-sectional study included 1790 participants aged ≥40 years. We analyzed data regarding the participants obtained in the 2016-2018 Korean National Health and Nutrition Examination Survey. The diagnosis of glaucoma was defined according to the International Society of Geographical and Epidemiological Ophthalmology criteria. Logistic regression analyses were used to investigate the relationship between blood folate levels and glaucoma. There was a significantly lower prevalence of glaucoma in the highest quartile of blood folate levels than in the lowest quartile, after adjusting for confounding factors such as age, sex, systemic hypertension, diabetes, hypercholesterolemia, and smoking (odds ratio [OR] = 0.470; 95% confidence interval [CI], 0.291-0.759; P for trend = 0.017). There was a significantly lower risk of glaucoma in the highest quartile of blood folate levels than in the lowest quartile among women (OR = 0.188; 95% CI, 0.099-0.357; P for trend <0.001) and younger participants (OR =0.443; 95% CI, 0.229-0.856; P for trend = 0.045). Our findings indicate a strong inverse correlation between blood folate levels and glaucoma.

Independent and combined effect of serum copper and folate on depression: cross-sectional data from the NHANES 2011-2016.

Depression is a widespread mental health condition that can impact both mental and physical well-being. Prior research has shown that high levels of copper in the blood and low levels of folate are linked to depression. This study aimed to explore whether serum folate levels, independently or in combination with serum copper levels, associated with the risk of depression. Data from participants aged 18-80 years in the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2016 were analyzed to examine the role of trace elements. Depression was assessed using the nine-item Patient Health Questionnaire (PHQ-9). Logistic regression analyses were employed to evaluate the main effect of serum copper and folate levels on depression. Three indices, including the relative excess risk of interaction (RERI), attributable proportion of interaction (API), and synergy index (SI), were used to analyze the interaction effect. Among the 4,847 participants selected for this study, 429 (8.9%) had PHQ-9 scores above 10, which we defined as having depressive symptoms. After adjusting for all confounding factors, higher serum copper levels [≥15.5 vs. <15.5 μmol/L, odds ratio (OR): 1.54; 95% confidence intervals (CI): 1.18-2.11] and folate deficiency (folate ≥53.7 vs. <53.7 μmol/L, OR: 1.44; 95% CI: 1.21-2.10) were associated with an increased risk of depression. Patients with both higher serum copper levels and folate deficiency (OR: 2.11; 95% CI: 1.43-3.14) had the highest risk of depression than other levels. High copper levels and low folate levels are associated with the occurrence of depression symptoms, and there may be a synergistic effect between them (SI: 1.65; 95% CI: 1.49-4.76), with this interaction accounting for 19% of depression cases (API: 0.19; 95% CI: 0.01-0.54). There may be a synergistic interaction between high copper levels and low folate levels associated with increasing risk of depression. Further population-based interventional studies are needed to confirm whether folic acid supplementation is effective in preventing depression in individuals with high blood copper levels.

The effect of Folic Acid, B12, D, and E Vitamins and Melatonin levels in the follicular fluid taken by the Intracytoplasmic Sperm Injection method on pregnancy.

It has been demonstrated that the composition of the follicular fluid and many internal/external factors affect success in subfertile couples undergoing intracytoplasmic sperm injection (ICSI). We examined the effect of folic acid, B12, D, and E vitamins and melatonin values in follicular fluid on pregnancy in women with low, normal, and high ovarian reserves who underwent ICSI. Our study was conducted at Samsun Medical Park Hospital between January 2021 and February 2022. Follicular fluid induction samples were taken from 96 infertile women with low, normal, and high ovarian reserve, and ICSI was applied. Folic acid, B12, D, and E vitamins and melatonin levels were measured in follicular fluid samples by ELISA method. Statistical analyzes were done with SPSS, and ROC curve analyses were used. Nine people with poor reserve, 19 people with normal reserve and 14 people with high reserve became pregnant. Folic acid, Vitamin-D, B12, E and melatonin levels were lower in those with poor ovarian reserve than in those with normal and high ovarian reserve (p<0.05). According to the pregnancy test, the probability of pregnancy was 43,783 times higher with high levels of folic acid, while it was 8,096 times higher for vitamin D. While vitamin B12 levels were 31,474 times more likely to be pregnancies, vitamin E levels were 35,227 times higher. For melatonin, the values showed that the probability of pregnancy increased by 11,564 times. High antioxidants may increase the likelihood of conception in infertile women undergoing ICSI. Therefore, couples who will be treated should be advised to increase these markers, especially melatonin in the follicular fluid.

Association of arsenic exposure with measles antibody titers in US children: Influence of sex and serum folate levels

Exposure to arsenic during childhood is associated with various adverse health conditions. However, little is known about the effect of arsenic exposure on vaccine-related humoral immunity in children. We analyzed data from the National Health and Nutrition Examination Survey (2003–2004 and 2009–2010) to study the relationship between urinary arsenic and measles antibody levels in 476 US children aged 6–11. Multivariable linear regression was used to evaluate the association, adjusting for cycle, age, race, body mass index (BMI), serum cotinine, poverty index ratio, and vitamin B12 and selenium intakes. Stratified analyses were conducted by sex and serum folate levels using the median as cutoff (18.7 ng/mL). The measles antibody concentrations in the 3rd and 4th quartiles were found to have significantly decreased by 28.5 % (95 % Confidence Interval (CI) −47.6, −2.28) and 36.8 % (95 % CI −50.2, −19.5), compared to the lowest quartile among boys with serum folate levels lower than 18.7 ng/ml. The serum measles antibody titers significantly decreased by 16.7 % (95 %CI −25.0, −7.61) for each doubling of creatinine-corrected urinary total inorganic arsenic concentrations in the same group. No associations were found in boys with high serum folate levels or in girls. Further prospective studies are needed to validate these findings and develop interventions to protect children from infectious diseases.

Potential folate-producing strains and their applications in biofortification of fermented Moringa oleifera leaves powder

Folate is an essential vitamin for the human body and must be obtained exogenously. It is recognized that some microorganisms are capable of producing folates during growth, revealing possibilities for innovations of natural folate biofortified foods. The aim of this study was to identify potential folate-producing strains to enhance folate content in fermented Moringa oleifera leaves powder (MOLP). Although most of the tested strains exhibited folate production, there were significant differences among them in terms of both quantity and distribution, whether intracellular or extracellular. 10 strains with potential for folate production were chosen for enhancing the folate content of MOLP. The two most promising strains, Lactiplantibacillus sp. LP1 and Saccharomyces cerevisiae Y-J-1, demonstrated high folate levels up to 1940 and 2115 μg/100 g dry matter, respectively. These levels were 1.6 and 1.8-fold the initial value in MOLP. Additionally, the fermentation of MOLP not only enhanced its nutritional quality but also preserved its significant bioactivity. This study provides the initial understanding of how selected microorganisms can naturally enrich folates in fermented MOLP, presenting an alternative solution to address the widespread issue of folate deficiency while promoting human health.

Purine Nucleotide Alterations in Tumoral Cell Lines Maintained with Physiological Levels of Folic Acid.

Most cancer cells have an increased synthesis of purine nucleotides to fulfil their enhanced division rate. The de novo synthesis of purines requires folic acid in the form of N10-formyltetrahydrofolate (10-formyl-THF). However, regular cell culture media contain very high, non-physiological concentrations of folic acid, which may have an impact on cell metabolism. Using cell culture media with physiological levels of folic acid (25 nM), we uncover purine alterations in several human cell lines. HEK293T, Jurkat, and A549 cells accumulate 5'-aminoimidazole-4-carboxamide ribonucleotide (ZMP), an intermediary of the de novo biosynthetic pathway, at physiological levels of folic acid, but not with the artificially high levels (2200 nM) present in regular media. Interestingly, HEK293T and Jurkat cells do not accumulate high levels of ZMP when AICAr, the precursor of ZMP, is added to medium containing 2200 nM folate; instead, ATP levels are increased, suggesting an enhanced de novo synthesis. On the other hand, HeLa and EHEB cells do not accumulate ZMP at physiological levels of folic acid, but they do accumulate in medium containing AICAr plus 2200 nM folate. Expression of SLC19A1, which encodes the reduced folate carrier (RFC), is increased in HEK293T and Jurkat cells compared with HeLa and EHEB, and it is correlated with the total purine nucleotide content at high levels of folic acid or with ZMP accumulation at physiological levels of folic acid. In conclusion, tumoral cell lines show a heterogenous response to folate changes in the media, some of them accumulating ZMP at physiological levels of folic acid. Further research is needed to clarify the ZMP downstream targets and their impact on cell function.

The Influence of Maternal Folate Status on Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis.

Maternal folate has been shown to relate to the risk of gestational diabetes mellitus (GDM). However, the existing studies have yielded inconsistent conclusions. The purpose of this study was to systematically review the association between maternal folate status and the risk of GDM. Observational studies up to 31 October 2022 were included. Study characteristics, the means and standard deviations (SDs) of folate levels (serum/red blood cell (RBC)), the odds ratios (ORs) with 95% confidence intervals (CIs) and the time for folate measurement were extracted. Compared with the non-GDM group, serum and RBC folate levels in women with GDM were significantly higher. Our subgroup analysis demonstrated that serum folate levels in the GDM group were significantly higher than in the non-GDM group only in the second trimester. RBC folate levels in the GDM group were significantly higher than in the non-GDM group in the first and second trimesters. Taking serum/RBC folate levels as continuous variables, the adjusted odds ratios of GDM risk showed that increased serum folate concentration rather than RBC folate elevated the risk of GDM. In the descriptive analysis, five studies reported high serum folate levels increased GDM risk, whereas the other five showed no association between serum folate levels and GDM risk. Moreover, the rest three studies pointed out high RBC folate levels increased GDM risk. Altogether we found that the risk of GDM is associated with high serum/plasma and RBC folate levels. Future studies should determine the recommended folic acid cutoff balancing the risk for GDM and fetal malformations.

Interplay between the Brassica napus phytoglobin (BnPgb1), folic acid, and antioxidant responses enhances plant tolerance to waterlogging

Oxygen deprivation by waterlogging reduces the productivity of several crop species, including the oil-producing crop Brassica napus L., which is highly sensitive to excess moisture. Among factors induced by oxygen deficiency are phytoglobins (Pgbs), heme-containing proteins known to ameliorate the response of plants to the stress. This study examined the early responses to waterlogging in B. napus plants over-expressing or down-regulating the class 1 (BnPgb1) and class 2 (BnPgb2) Pgbs. The depression of gas exchange parameters and plant biomass was exacerbated by the suppression of BnPgb1, while suppression of BnPgb2 did not evoke any changes. This suggests that natural occurring levels of BnPgb1 (but not BnPg2) are required for the response of the plants to waterlogging. Typical waterlogging symptoms, including the accumulation of reactive oxygen species (ROS) and the deterioration of the root apical meristem (RAM) were attenuated by over-expression of BnPgb1. These effects were associated with the activation of antioxidant system and the transcriptional induction of folic acid (FA). Pharmacological treatments revealed that high levels of FA were sufficient to revert the inhibitory effect of waterlogging, suggesting that the interplay between BnPgb1, antioxidant responses and FA might contribute to plant tolerance to waterlogging stress.

MICRONUTRIENT INTAKE AND HYPERTENSION AMONG ADOLESCENTS, NHANES 2007-2018

Objective: To examine the relationship between nutrient intake and hypertension (HTN) diagnosis in adolescents. Design and method: This cross-sectional study analyzed representative nutrient and sociodemographic factors from six 2-year cycles (2007 to 2008 through 2017 to 2018) of the National Health and Nutrition Examination Survey. The sample included adolescent survey participants,13 to 18 years of age. Nutrient intake estimates were derived from total dietary recall and daily supplement recall data. Systolic and diastolic HTN were defined based upon the average of 2-3 measured blood pressures. An average systolic blood pressure at or above 130mmHg was used to identify adolescents with systolic HTN, while an average diastolic blood pressure at or above 80mmHg was used to identify youth with diastolic HTN. Using descriptive statistics, inclusive of chi-square analysis for categorical data and Wilcoxon rank sum test for continuous data, we assessed the relationship between a variety of sociodemographic variables, nutrient variables and systolic HTN (or diastolic HTN). Logistic regression was performed to determine factors associated with a greater odd of HTN. Goodness of Fit of the logistic regression model was assessed. Results: Among 5866 US adolescents, the sodium to potassium ratio was higher and the folate level lower among youth with systolic HTN. Other factors associated with systolic HTN included older age, male sex, and obesity. According to the logistic regression model, factors associated with a greater odd of systolic HTN included age, sex (male), and obesity. Higher folate levels were associated with a lower odd of systolic HTN. Among youth with diastolic HTN, only age and obesity were associated. Conclusions: Hypertension (HTN) is the most common preventable cause of cardiovascular disease (CVD) in the US and globally. It is prevalent in 2-4% of youth.1, 2 Nutrient intake and HTN in adolescents has major public health implications. Like previously published findings in adults, 3 we found that folate &gt; 5000mcg is associated with lower blood pressure. In this study, sodium intake, potassium intake, magnesium and lycopene levels were not associated with HTN in adolescents.

Two Faces of Catechol-O-Methyltransferase Inhibitor on One-Carbon Metabolism in Parkinson’s Disease: A Meta-Analysis

Levodopa (L-dopa) and catechol-O-methyltransferase (COMT) inhibition are widely used therapeutics in Parkinson's disease (PD). Despite their therapeutic effects, it was raised that nutrients involved in one-carbon metabolism can be deteriorated by PD therapies. The aim of this meta-analysis was to investigate the impact of L-dopa and COMT inhibitors on levels of homocysteine (Hcy), vitamin B12 and folate in patients with PD. A total of 35 case-control studies from 14 different countries were selected through PubMed, MEDLINE and Google Scholar and were meta-analyzed. In the L-dopa group, the Hcy level was higher compared to the PD without L-dopa group (SMD: 5.11 μmol/L, 95% CI: 3.56 to 6.66). Moreover, vitamin B12 and folate levels in the L-dopa group were lower compared to the healthy control (SMD: -62.67 pg/mL, 95% CI: -86.53 to -38.81; SMD: -0.89 ng/mL, 95% CI: -1.44 to -0.33, respectively). The COMT inhibitor group showed lower levels of Hcy (SMD: -3.78 μmol/L, 95% CI: -5.27 to -2.29) and vitamin B12 (SMD: -51.01 pg/mL, 95% CI: -91.45 to -10.57), but higher folate levels (SMD: 1.78 ng/mL, 95% CI: -0.59 to 4.15) compared to the L-dopa group. COMT inhibitors may ameliorate L-dopa-induced hyper-homocysteine and folate deficiency but exacerbate vitamin B12 deficiency.

The association of serum folate and homocysteine on venous thromboembolism in patients with colorectal cancer: a cross-sectional study.

Venous thromboembolism is a common complication in patients with colorectal cancer who exhibit high homocysteine and low folate levels. However, whether venous thrombosis is the result of a direct effect of folic acid or the presence of a homocysteine-mediated mediating effect cannot be determined. This study aimed to explore the association and mediating effects of serum folate and homocysteine on venous thromboembolism in patients with colorectal cancer. This study included patients with colorectal cancer who were admitted to the First Hospital of Shanxi Medical University from May 2020 to May 2022. The patients' medical records were reviewed to collect information on general demographic characteristics, the prevalence of venous thromboembolism on admission, laboratory blood indices, serum folate, and serum homocysteine. SPSS 26.0 software was used for data collation and statistical analysis; the χ2 test was utilized for univariate analysis and unconditional logistic regression was applied for multivariate analysis. R 4.1.2 was used to perform the mediating effect test. A total of 236 colorectal cancer patients were investigated. The prevalence of colorectal cancer combined with venous thromboembolism was 15.3%; serum folate was <10.75 nmol/L in 25.4% of patients; and serum homocysteine was ≥22 µmol/L in 30.5% of patients. After controlling for confounding factors, the risk of venous thromboembolism was 2.48 times greater [95% confidence interval (CI): 1.04 to 5.94] in patients with low serum folate (<10.75 nmol/L) than in those with high serum folate (≥10.75 nmol/L). Also, the risk of venous thromboembolism was greater in those with high serum homocysteine (≥22 µmol/L) [odds ratio (OR) =2.99. 95% CI: 1.11 to 8.08]. The mediating effect test showed no direct effect of serum folate on venous thromboembolism combined with colorectal cancer, and a full mediating effect of serum homocysteine between serum folate and venous thromboembolism combined with colorectal cancer, with a mediating effect value of 0.002 and a total effect value of 0.0054. Serum folate influences the formation of venous thromboembolism through serum homocysteine. It is recommended that the nutritional supplementation of patients be enhanced to control serum folate and serum homocysteine levels.

Reduced γ-glutamyl hydrolase activity likely contributes to high folate levels in Periyakulam-1 tomato.

Tomato cultivars show wide variation in nutraceutical folate in ripe fruits, yet the loci regulating folate levels in fruits remain unexplored. To decipher regulatory points, we compared two contrasting tomato cultivars: Periyakulam-1 (PKM-1) with high folate and Arka Vikas (AV) with low folate. The progression of ripening in PKM-1 was nearly similar to AV but had substantially lower ethylene emission. In parallel, the levels of phytohormones salicylic acid, ABA, and jasmonic acid were substantially lower than AV. The fruits of PKM-1 were metabolically distinct from AV, with upregulation of several amino acids. Consistent with higher °Brix, the red ripe fruits also showed upregulation of sugars and sugar-derived metabolites. In parallel with higher folate, PKM-1 fruits also had higher carotenoid levels, especially lycopene and β-carotene. The proteome analysis showed upregulation of carotenoid sequestration and folate metabolism-related proteins in PKM-1. The deglutamylation pathway mediated by γ-glutamyl hydrolase (GGH) was substantially reduced in PKM-1 at the red-ripe stage. The red-ripe fruits had reduced transcript levels of GGHs and lower GGH activity than AV. Conversely, the percent polyglutamylation of folate was much higher in PKM-1. Our analysis indicates the regulation of GGH activity as a potential target to elevate folate levels in tomato fruits.

Circulating homocysteine and folate concentrations and risk of type 2 diabetes: A retrospective observational study in Chinese adults and a Mendelian randomization analysis.

The relation between circulating homocysteine (hcy) and folate concentrations and risk of type 2 diabetes mellitus (T2DM) has been evaluated in several observational studies with inconsistent results; and it is unclear about their causal relationships. Our aim was to assess the causality association between circulating hcy or folate concentrations and the development of T2DM using Mendelian randomization (MR) analysis, based on results of an observational study in Chinese adults. We conducted an observational study of 370 patients with T2DM and 402 controls after routine physical examination who consulted at the Zhongnan Hospital of Wuhan University between March 2021 and December 2021. Correlations between hcy and folate and the incidence of T2DM were quantified using logistic regression models. Two-sample MR analysis was conducted using summary statistics of genetic variants gained from 2 genome-wide association studies (GWAS) on circulating hcy and folate concentrations in individuals of European ancestry and from an independent GWAS study based on DIAMANTE meta-analysis. In the observational study, after logistic regression with multiple adjustment, lower hcy and higher folate levels were identified to be associated with the risk of T2DM, with OR (95% CI) for hcy of 1.032 (1.003-1.060); while 0.909 (0.840-0.983) for folate. In the MR analysis, the OR for T2DM was 1.08 (95% CI: 0.95, 1.21; P = 0.249) for each SD unit increase in genetically predicted homocysteinemia and the OR for T2DM per SD increase in genetically predicted folate elevation was 0.80 (95% CI: 0.60, 1.00, P = 0.026). We discovered that high circulating hcy and low folate concentrations were related with an increased risk of developing T2DM in Chinese adults. Moreover, MR analysis provided genetic evidence for a possible causal relationship between serum folate and the risk of T2DM.