Methionine Synthase Research Articles

New atherosclerosis progression markers in patients with post-Chernobyl metabolic syndrome

Relevance. As an epidemiologically proven consequence of the Chernobyl NPP accident, circulatory diseases are among the leading morbidities in liquidators. To predict the development of adverse cardiovascular events in patients with metabolic syndrome, there is the ongoing search for informative laboratory markers.The objective is to show how osteopontin, osteoprotegerin, fetuin-A, and risk factors for genetic circulatory disorders are associated with traditional risk factors for circulatory disorders in Chernobyl nuclear power plant accident liquidators suffering metabolic syndrome. Another objective is to explore the perspectives to use these indicators to forecast coronary atherosclerosis progression.Methods. The study group included 50 male liquidators of the Chernobyl nuclear power plant accident who suffered metabolic syndrome. The patients were split in two groups depending on osteopontin concentration in blood serum, i.e. above or under the upper reference limit. Medical history data, biochemical parameters, including inflammatory proteins, osteoprotegerin, fetuin-A, and genotyping of polymorphic variants of genes associated with the risk of circulatory diseases were analyzed. A control group of 30 conditionally healthy men was formed to determine the normal osteopontin, osteoprotegerin and fetuin-A values in blood serum.Results and discussion. With osteopontin value exceeding 21.4 ng/mL, the liquidators’ medical history showed 1.5 times higher frequency of myocardial infarction, 2.5 times higher frequent history of acute cerebral circulation disorder; ischemic heart disease was associated with type 2 diabetes mellitus. It was shown that the group of liquidators (osteopontin over 21.4 ng/ml) was characterized by a reliable increase in atherogenicity coefficient and osteoprotegerin level. Meanwhile, when compared to the control group, the same group of patients showed lower fetuin-A values and elevated high-sensitivity C-reactive protein, homocysteine, leptin and ghrelin. It was found that in liquidators, the presence of the A allele in the vitamin B12-dependent methionine synthase (MTR) gene (2756 A>G) is associated with more pronounced biochemical markers of atherosclerosis progression compared to GG genotype carriers.Conclusion. Osteopontin performs a protective role in tissue damage, being is practically undetectable in normal conditions. However, in case of pathology its value increases dramatically. In patients with metabolic syndrome, decreased fetuin-A and osteopontin values exceeding 21.4 ng/mL require additional examination with a focus on cardiovascular pathology (coronary artery calcinosis), as well as a dual-energy X-ray absorptiometry to ensure early detection of diminished bone mineral density and body mass. It was found that in liquidators, the presence of A-allele (genotypes AA and AG) in the MTR 2756 A>G gene is characterized by deeper atherogenic changes in the lipid spectrum, increased atherogenicity coefficient and decreased adiponectin content. This justifies the need for genotyping to build individual forecast for atherosclerosis progression in this category of patients.

Homocysteine S-Methyltransferase 3 Positively Regulates Cadmium Tolerance in Maize.

The increasing contamination of agricultural soils with cadmium (Cd) poses a significant threat to human health and global food security. Plants initiate a series of mechanisms to reduce Cd toxicity. However, the response of maize to Cd toxicity remains poorly understood. In this study, we identified that ZmHMT3, which encodes a homocysteine S-methyltransferases family protein, acted as a regulator of Cd tolerance in maize. Subcellular localization and in situ PCR exhibited that ZmHMT3 was localized in the cytoplasm and predominantly expressed in the phloem. Overexpression of ZmHMT3 enhanced Cd tolerance and reduced Cd concentration in both shoots and roots. In contrast, ZmHMT3 mutants attenuated Cd tolerance but did not change shoot Cd concentration. Heterologous overexpression of ZmHMT3 in rice enhanced Cd tolerance and reduced grain Cd concentration. Transcriptome analysis revealed that ZmHMT3 upregulated the expression of stress-responsive genes, especially glutathione S-transferases (GSTs) and transcription factors, including MYBs, NACs and WRKYs, and modulates the expression of different ATP-binding cassette (ABC) transporters, thereby enhancing Cd tolerance. Collectively, these findings highlight the pivotal role of ZmHMT3 in Cd tolerance and as a candidate gene for improving Cd tolerance in elite maize varieties.

Study of the relationships of polymorphisms of the folate cycle genes with the levels of homocysteine and folic acid as risk factors of cardiovascular disorders in the post-covid period

Enzymes of the folate cycle participate in the process of remethylation of homocysteine (HC) to methionine, where folates are coenzymes for methyl transfer. The aim of the work was to identify the interrelationships of gene polymorphisms of associations between folate cycle enzyme gene polymorphisms and cardiometabolic risk factors such as increased serum homocysteine levels and folic acid deficiency in patients in the post-covid period. In 51 patients who suffered from COVID-19, a general clinical and laboratory examination, and assessment of serum homocysteine and folic acid concentrations by immunoenzymatic method was carried out. Polymorphisms of the genes: methylenetetrahydrofolate reductase (677C>T and 1298A>C), methionine synthase-reductase (66A>G) and methionine synthase (2756A>G) were determined by real time polymerase chain reaction. For each of the named polymorphisms, the examined patients were divided into 3 groups according to the nucleotide alleles in the corresponding position: 1) homozygous dominant, 2) heterozygous and 3) homozygous recessive. For the methylenetetrahydro­folatereductase gene at position 677, serum levels of homocysteine and folate did not differ between the groups 1 and 2 with genotypes 677 C/C (n=26) and 677C/T (n=21), (p>0.05); in group 3, the recessive genotype 677 T/T was found in only 4 people (8%), that did not allow comparison of indices. The distribution of patients into 3 groups according to the genotype of the same gene at position 1298 revealed that the recessive 1298 C/C mutation in group 3 (n=9) associated with an increased homocysteine level (19.56±1.89 μmol/l), versus 10.68±0.76 (p=0.012) and 11.63±1.25 μmol/l (p=0.013) in groups 1 and 2, with no difference in folate levels between groups. Group 3 differed by a higher degree of obesity, a higher frequency of hypertension disease and chronic heart failure (in 85% of patients in group 3, against 41 and 50% in groups 1 and 2), a higher number of platelets, a longer duration of hospitalization due to COVID-19, a higher level of D-dimer. The study of groups of patients, divided depending on the genotype of methioninesynthase reductase at position 66, showed that carriers of the recessive homozygous 66 G/G mutation (group 3, n=15) had increased serum homocysteine level (16.56±1.64 μmol/l) in comparison with individuals of group 1 (n=17) 66 A/A (10.28±1.17 μmol/l; p=0.004) and group 2 (n=19) 66 A/G (11.32±1.17 μmol/l, p=0.013). In group 3, a longer duration of hospitalization due to COVID-19 was noted (17.15±1.65 vs. 11.88±0.97 days, p=0.008), higher frequency of hypertension (67% vs. 35%) and heart failure (67% against 29%) compared to group 1. The use of a molecular genetic approach made it possible to establish that the presence of recessive mutations of the folate cycle genes is associated with a potential predisposition to hyperhomocysteinemia, thrombophilia, severe forms of cardiometabolic complications and coronavirus disease.

B-283 Biological Consequences of Nitrous Oxide Abuse: Insights from Targeted Metabolomics Investigation

Abstract Background The recreational use of nitrous oxide (N2O), commonly known as laughing gas, has experienced a notable surge in popularity in recent times. According to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA), N2O is recognized as one of the most widely used psychoactive substances in Europe as of 2022. Its use also extends to Asia and America, according to literature. However, prolonged consumption of N2O has been associated with neurological complications linked to the functional inactivation of vitamin B12, disrupting One Carbon Metabolism. This study aims to explore the metabolic effects of N2O intoxication through a targeted metabolomics approach. Methods We conducted a prospective collection of clinical and biological information from 37 N2O users and 37 non-users (control group). Utilizing a targeted metabolomics method, we analyzed plasma amino acids using liquid chromatography coupled with mass spectrometry. Our statistical analysis encompassed principal component analyses, random forests, Mann-Whitney tests, Student's t-tests, and Spearman rank tests. Results Metabolomic analyses have demonstrated effective differentiation between patient groups. In comparison to controls, N2O consumers displayed reduced plasma levels of taurine, cystine, and methionine, alongside elevated plasma levels of serine and sarcosine. These findings suggest a potential influence of N2O on the cystine-methionine metabolic pathway. The decrease in methionine levels may be attributed to the decreased activity of methionine synthase (MS) due to vitamin B12 inactivation, which could partially explain the observed increase in serine levels. The rise in sarcosine levels could be explained by an increase in betaine-homocysteine S-methyltransferase (BHMT) activity. Moreover, dysfunction in cystathionine-β-synthase (CBS) or cystathionine γ-lyase (γ-CYS) may lead to the accumulation of upstream metabolites (such as serine) and a reduction in downstream metabolites (such as cysteine and taurine). Conclusions This study sheds light on potential new impacts of N2O, particularly on the plasma levels of serine, cystine, and taurine, indicating a potential modulation of enzymes involved in the conversion of homocysteine to taurine (CBS and/or γ-CYS). Additional investigations are required in a larger group of patients, which corresponds to the aims of the EFLM Task & Finish Group: Biomarkers of Diagnosis and Follow-up of Nitrous Oxide Abuse: https://www.eflm.eu/site/who-we-are/committee/science-committee/fu/tfg-biomarkers-of-diagnosis

Production and utilization of pseudocobalamin in marine Synechococcus cultures and communities.

Cobalamin influences marine microbial communities because an exogenous source is required by most eukaryotic phytoplankton, and demand can exceed supply. Pseudocobalamin is a cobalamin analogue produced and used by most cyanobacteria but is not directly available to eukaryotic phytoplankton. Some microbes can remodel pseudocobalamin into cobalamin, but a scarcity of pseudocobalamin measurements impedes our ability to evaluate its importance for marine cobalamin production. Here, we perform simultaneous measurements of pseudocobalamin and methionine synthase (MetH), the key protein that uses it as a co-factor, in Synechococcus cultures and communities. In Synechococcus sp. WH8102, pseudocobalamin quota decreases in low temperature (17°C) and low nitrogen to phosphorus ratio, while MetH did not. Pseudocobalamin and MetH quotas were influenced by culture methods and growth phase. Despite the variability present in cultures, we found a comparably consistent quota of 300 ± 100 pseudocobalamin molecules per cyanobacterial cell in the Northwest Atlantic Ocean, suggesting that cyanobacterial cell counts may be sufficient to estimate pseudocobalamin inventories in this region. This work offers insights into cellular pseudocobalamin metabolism, environmental and physiological conditions that may influence it, and provides environmental measurements to further our understanding of when and how pseudocobalamin can influence marine microbial communities.

Presence of vitamin B12 metabolism in the last common ancestor of land plants.

Vitamin B12, also known as cobalamin, is an essential organic cofactor for methionine synthase (METH), and is only synthesized by a subset of bacteria. Plants and fungi have an alternative methionine synthase (METE) that does not need B12 and are typically considered not to utilize it. Some algae facultatively utilize B12 because they encode both METE and METH, while other algae are dependent on B12 as they encode METH only. We performed phylogenomic analyses of METE, METH and 11 further proteins involved in B12 metabolism across more than 1600 plant and algal genomes and transcriptomes (e.g. from OneKp), demonstrating the presence of B12-associated metabolism deep into the streptophytes. METH and five further accessory proteins (MTRR, CblB, CblC, CblD and CblJ) were detected in the hornworts (Anthocerotophyta), and two (CblB and CblJ) were identified in liverworts (Marchantiophyta) in the bryophytes, suggesting a retention of B12-metabolism in the last common land plant ancestor. Our data further show more limited distributions for other B12-related proteins (MCM and RNR-II) and B12 dependency in several algal orders. Finally, considering the collection sites of algae that have lost B12 metabolism, we propose freshwater-to-land transitions and symbiotic associations to have been constraining factors for B12 availability in early plant evolution. This article is part of the theme issue 'The evolution of plant metabolism'.

Kidney-Limited Microangiopathy Associated with Methionine Synthase (Cobalamin G) Deficiency in a Pediatric Patient: Case Report and Review of the Literature

Thrombotic microangiopathy (TMA) is a recognized sequela of inborn errors of metabolism impacting vitamin B12 (cobalamin) synthesis. Methylmalonic aciduria and homocystinuria, cobalamin deficiency type C is a well-known etiology for TMA. TMA has only rarely previously been reported in methionine synthase (cobalamin G) deficiency. Furthermore, results of only 7 kidney biopsies have previously been reported in this clinical setting. Here, we report a case of kidney- and glomerular-limited chronic active microangiopathy demonstrated on kidney biopsy in a patient with biochemically confirmed cobalamin G deficiency. A literature review of all prior reported cases is also presented and demonstrates hypertension, proteinuria, and hematuria to be common presenting symptoms. Age on onset ranged from 7 months to 14 years. Kidney-limited phenotype was less common and occurred only in older children. Acute kidney injury was more common in younger patients. Therapy with hydroxocobalamin and angiotensin-converting enzyme inhibitors resulted in variable clinical responses.

Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) gene polymorphisms and five related serum molecular levels in 2587 patients: Associated differentially with adverse pregnancy.

The aim of the study is to investigate the relationship between Methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR) polymorphisms, 5 serum related molecular levels and the risk of adverse pregnancies in different genders. Patients aged from 22 to 38 with a history of adverse pregnancy treated in our genetic eugenics clinic of Henan Provincial People's Hospital are selected. The controls aged from 20 to 34 undergoing eugenics examinations in our genetic eugenics clinic that had no history of adverse pregnancy and at least one healthy child are selected. Sanger sequencing and Chemiluminescence Microparticle Immuno Assay (CMIA) are used for detecting the mutations of MTHFR and MTRR and the 5 serum molecular serum levels. In the female group, MTHFR 677C > T is associated with Recurrent spontaneous abortion (RSA) (P = 0.0017), Chromosomal abnormality (CA) (P = 0.0053), Cleft lip and palate (CLP) (P = 0.0326) and Brain dysplasia (BD) (P = 0.0072); MTHFR 1298A > C is associated with Infertility (P = 0.0026) and BD (P = 0.0382); MTRR 66A > G is associated with CLP (P = 0.0131). In the male group, MTHFR 677C > T is associated with RSA (P = 0.0003), Infertility (P = 0.0013), CA (P = 0.0027) and BD (P = 0.0293). In the female group, the genotype of MTHFR 677C > T is associated with RSA (P = 0.0017), CA (P = 0.0014) and BD (P = 0.0021); MTHFR 1298A > C is associated with Infertility (P = 0.0081) and MTRR 66A > G is associated with Infertility (P = 0.0309). In the male group, the genotype of MTHFR 677C > T is associated with RSA (P = 0.0008), Infertility (P = 0.0096) and CA (P = 0.0165) and MTRR 66A > G is associated with Infertility (P = 0.0158) and congenital heart disease (CHD) (P = 0.0218). In the male group, there is statistically significant difference of the serum Homocysteine (Hcy) levels (P < 0.0001) between adverse pregnancy group and controls.In the female group,there is statistically significant difference of the serum vitamin D levels (P = 0.0015) between adverse pregnancy group and controls. Polymorphic variants in MTHFR and MTRR, serum Folic acid (FA), Hcy and B12 levels in the male group and vitamin D levels in the female group are associated differentially with adverse pregnancy.

Expression patterns of folate metabolism-related enzymes in the bovine oviduct: estrous cycle-dependent modulation and responsiveness to folic acid

Folate metabolism is required for important biochemical processes that regulate cell functioning, but its role in female reproductive physiology in cattle during peri- and post-conceptional periods has not been thoroughly explored. Previous studies have shown the presence of folate in bovine oviductal fluid, as well as finely regulated gene expression of folate receptors and transporters in bovine oviduct epithelial cells (BOECs). Additionally, extracellular folic acid (FA) affects the transcriptional levels of genes important for the functioning of BOECs. However, it remains unknown whether the anatomical and cyclic features inherent to the oviduct affect regulation of folate metabolism. The present study aimed to characterize the gene expression pattern of folate cycle enzymes in BOECs from different anatomical regions during the estrous cycle and to determine the transcriptional response of these genes to increasing concentrations of exogenous FA. A first PCR screening showed the presence of transcripts encoding dihydrofolate reductase (DHFR), methylenetetrahydrofolate reductase (MTHFR), and methionine synthase (MTR) in bovine reproductive tissues (ovary, oviduct and uterus), with expression levels in oviductal tissues comparable to, or even higher than, those detected in ovarian and uterine tissues. Moreover, expression analysis through RT-qPCR in BOECs from the ampulla and isthmus during different stages of the estrous cycle demonstrated that folate metabolism-related enzymes exhibited cycle-dependent variations. In both anatomical regions, DHFR was upregulated during the preovulatory stage, while MTHFR and MTR exhibited increased expression levels during the postovulatory stage. Under in vitro culture conditions, ampullary and isthmic cells were cultured in the presence of 10, 50, and 100 μM FA for 24 h. Under these conditions, isthmus epithelial cells exhibited a unique transcriptional response to exogenous FA, showing a pronounced increase in MTR expression levels. Our results suggest that the expression of folate metabolism-related genes in BOECs is differentially regulated during the estrous cycle and may respond to exogenous levels of folate. This offers a new perspective on the transcriptional regulation of genes associated with the folate cycle in oviductal cells and provides groundwork for future studies on their functional and epigenetic implications within the oviductal microenvironment.

Standardization and application of ARMS TaqMan real-time PCR for screening of folate metabolism genes in Han Chinese.

Folate has antioxidant properties, and low concentration in seminal plasma may be associated with increased DNA damage in sperm. Mutations of the methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) genes, including MTHFR C677T (rs1801133), MTHFR A1298C (rs1801131), and MTRR A66G (rs1801394), can lead to decreased activity of the encoded folate metabolic enzymes, thereby affecting male reproduction. The current SNP detection methods commonly used in clinical practice have some shortcomings, such as long time-consuming, complex detection steps, or high cost. The purpose of this study was to establish a simple, time-saving, sensitive, accurate, and easy to clinical popularization method for folate metabolism gene detection. We combined ARMS-PCR with TaqMan fluorescent probe to establish an ARMS TaqMan real-time PCR detection method. According to the variation of rs1801131, rs1801133, and rs1801394, two specific primers (one wild type and one mutant) were designed. Mismatched nucleotides were introduced at the penultimate or third position to improve the specificity of the primer. Specific TaqMan probe was introduced to detect PCR products to improve the sensitivity of the method. The results showed that the sensitivity of ARMS TaqMan real-time PCR in SNP genotyping was 1ng, and the accuracy was 100%. A total of 249 clinical samples were detected by the established method, and the correlation between three SNPs and semen quality was analyzed. We found that individuals carrying the AG+GG genotype of rs1801394 had a lower risk of abnormal semen quality. In conclusion, we developed a highly sensitive, accurate, rapid, and easy to be popularized method for detecting SNPs of rs1801394, rs1801131, and rs1801133. ARMS TaqMan real-time PCR is a reliable SNP genotyping method in folate metabolism genes.

Excess Folic Acid Exposure Increases Uracil Misincorporation into DNA in a Tissue-Specific Manner in a Mouse Model of Reduced Methionine Synthase Expression

BackgroundFolate and vitamin B12 (B12) are cofactors in folate-mediated 1-carbon metabolism (FOCM), a metabolic network that supports synthesis of nucleotides (including thymidylate [dTMP]) and methionine. FOCM impairments such as a deficiency or imbalance of cofactors can perturb dTMP synthesis, causing uracil misincorporation into DNA. ObjectiveThe purpose of this study was to determine how reduced expression of the B12-dependent enzyme methionine synthase (MTR) and excess dietary folic acid interact to affect folate distribution and markers of genome stability in mouse tissues. MethodsHeterozygous Mtr knockout mice (Mtr+/–) model the FOCM-specific effects of B12 deficiency. Folate accumulation and vitamer distribution, genomic uracil concentrations, and phosphorylated histone H2AX (γH2AX) immunostaining were measured in male Mtr+/+ and Mtr+/− mice weaned to either a folate-sufficient control (C) diet (2 mg/kg folic acid) or a high folic acid (HFA) diet (20 mg/kg folic acid) for 7 wk. ResultsExposure to the HFA diet led to tissue-specific patterns of folate accumulation, with plasma, colon, kidney, and skeletal muscle exhibiting increased folate concentrations compared with control. Liver total folate did not differ. Although unmetabolized folic acid (UMFA) increased 10-fold in mouse plasma with HFA diet, UMFA accounted for <0.2% of total folate in liver and colon tissue. Exposure to HFA diet resulted in a shift in folate distribution in colon tissue with higher 5-methyl-THF and lower formyl-THF than in control mice. Mtr heterozygosity did not impact folate accumulation or distribution in any tissue. Mice on HFA diet exhibited higher uracil in genomic DNA and γH2AX foci in colon. Similar differences were not seen in liver. ConclusionsThis study demonstrates that folic acid, even when consumed at high doses, does not meaningfully accumulate in mouse tissues, although high-dose folic acid shifts folate distribution and increases uracil accumulation in genomic DNA in colon tissue.

Folate and cobalamin status, indicators, modulators, interactions, and reference ranges from early pregnancy until birth: the Reus–Tarragona birth cohort study

BackgroundFolate and cobalamin status, although essential for pregnancy, are not routinely monitored in prenatal care. ObjectivesTo investigate folate and cobalamin status and determinants throughout pregnancy, in the absence of mandatory folic acid (FA) fortification. MethodsIn a cohort study of 831 mothers recruited at <12 gestational weeks (GW), plasma folate, total homocysteine (tHcy), cobalamin, holotranscobalamin (holoTC), methylmalonic acid (MMA), red blood cell folate (RBCF), and the combined cobalamin status indicator (cB12) were determined at ≤12, 15, 24–27, 34 GW, labor and in the cord. Single nucleotide polymorphisms affecting folate and cobalamin status were determined. FA, cobalamin, micronutrient supplement use, and dietary folate and cobalamin intake (food frequency questionnaire) were recorded. Folate and cobalamin status predictors were assessed by multiple linear regression analysis. ResultsOnly 36.1% of the participants took FA preconceptionally and 47.4% and 7.3% had suboptimal RBCF (<906 nmol/L) and plasma cobalamin status (≤221 pmol/L), respectively, at ≤12 GW. RBCF determinants included planned pregnancy, FA supplementation, plasma cobalamin, and methylenetetrahydrofolate (MTHFR) 677C>T genotype. Cobalamin supplementation was positively associated with plasma cobalamin and early holoTC. Smoking and BMI were inversely associated with plasma cobalamin and early holoTC, but none were associated with MMA. Only participants with the MTHFR 677TT genotype, exceeding FA supplement recommendations, improved their folate status (interaction term: B (95% CI):0.15 (0.01, 0.29), P = 0.032). Smoking was inversely associated with plasma cobalamin status in participants with the methionine synthase reductase (MTRR) 524CC genotype only (interaction term:0.07 (0.01, 0.04), P = 0.014). Mothers with low early pregnancy cobalamin status and also those with bigger newborns, had lower cobalamin status at labor. ConclusionsSuboptimal early pregnancy folate or cobalamin status affected 47.4% and 7.3% of the participants, respectively. The MTHFR 677TT genotype predicted folate status throughout pregnancy. Smoking and BMI were negatively associated with cobalamin status throughout pregnancy.Clinical Trial Registry number and website where it was obtained: NCT01778205. www.clinicaltrials.gov

LncRNA H19 promoted alcohol-associated liver disease through dysregulation of alternative splicing and methionine metabolism.

Long noncoding RNAs constitute a significant portion of the human genome. Among these, lncRNA H19, initially identified for its high expression during fetal development followed by a decline in the liver postnatally, re-emerges in various liver diseases. However, its specific role in alcohol-associated liver disease (ALD) remains unclear. Elevated H19 levels were detected in peripheral blood and livers of patients with alcohol-associated cirrhosis and hepatitis, as well as in livers of ethanol-fed mice. Hepatic overexpression of H19 exacerbated ethanol-induced liver steatosis and injury. Metabolomics analysis revealed decreased methionine levels in H19-overexpressed mouse livers, attributable to H19-mediated inhibition of betaine homocysteine methyltransferase (BHMT), a crucial enzyme in methionine synthesis. H19 regulated BHMT alternative splicing through polypyrimidine tract-binding protein 1 (PTBP1), resulting in a reduced Bhmt protein-coding variant. The maternally specific knockout of H19 (H19Mat+/-) or liver-specific knockout of the H19 differentially methylated domain (H19DMDHep-/-) in ethanol-fed mice upregulated BHMT expression and ameliorated hepatic steatosis. Furthermore, BHMT restoration counteracted H19-induced ethanol-mediated hepatic steatosis. This study identifies a novel mechanism whereby H19, via PTBP1-mediated BHMT regulation, influences methionine metabolism in ALD. Targeting the H19-PTBP1-BHMT pathway may offer new therapeutic avenues for ALD.

Chlorquinaldol Alleviates Lung Fibrosis in Mice by Inhibiting Fibroblast Activation through Targeting Methionine Synthase Reductase.

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease with limited treatment options. Thus, it is essential to investigate potential druggable targets to improve IPF treatment outcomes. By screening a curated library of 201 small molecules, we have identified chlorquinaldol, a known antimicrobial drug, as a potential antifibrotic agent. Functional analyses have demonstrated that chlorquinaldol effectively inhibits the transition of fibroblasts to myofibroblasts in vitro and mitigates bleomycin-induced pulmonary fibrosis in mice. Using a mass spectrometry-based drug affinity responsive target stability strategy, we revealed that chlorquinaldol inhibited fibroblast activation by directly targeting methionine synthase reductase (MTRR). Decreased MTRR expression was associated with IPF patients, and its reduced expression in vitro promoted extracellular matrix deposition. Mechanistically, chlorquinaldol bound to the valine residue (Val-467) in MTRR, activating the MTRR-mediated methionine cycle. This led to increased production of methionine and s-adenosylmethionine, counteracting the fibrotic effect. In conclusion, our findings suggest that chlorquinaldol may serve as a novel antifibrotic medication, with MTRR-mediated methionine metabolism playing a critical role in IPF development. Therefore, targeting MTRR holds promise as a therapeutic strategy for pulmonary fibrosis.

MTHFR polymorphisms and vitamin B12 deficiency: correlation between mthfr polymorphisms and clinical and laboratory findings.

Vitamin B12 deficiency is a common condition that causes a variety of disorders ranging from the development of megaloblastic anemia to the building up of neurological damage. Historically one of the leading causes of B12 deficiency appears to be secondary to malabsorption in part caused by the development of atrophic gastritis in pernicious anemia. More recently B12 deficiency could also depend on dietary restrictions. Cobalamin deficiency also appears to be closely related to folate metabolism, causing a reduction in methionine synthase activity. This results in the accumulation of 5-methyltetrahydrofolate (5-MTHF) and defective DNA synthesis. It has been hypothesized that reduced activity of the enzyme methylene-tetrahydrofolate reductase (MTHFR) could reduce the production of 5-MTHF, thereby shifting folate metabolism to thymidylate synthesis and promoting proper DNA synthesis. Our aim was to investigate the role of the C677T and A1298C MTHFR gene polymorphisms, which are associated with reduced enzyme activity, in predisposing to the development of anemia, neurological symptoms, and atrophic gastritis in a population of 105 consecutive Italian patients with cobalamin deficiency. We found statistically significant correlations between the degree of anemia and thrombocytopenia and the C677T MTHFR polymorphism, while hemoglobin levels alone significantly correlated with A1298C polymorphism, contradicting the potential protective role of these polymorphisms. Furthermore, in patients with atrophic gastritis, we found an association between the absence of parietal cell antibodies and the presence of the C677T polymorphism in homozygosity. Our results suggest a role for MTHFR enzyme activity in the severity of hematologic manifestations of vitamin B12 deficiency and as an independent mechanism of predisposition to the development of atrophic gastritis.

Polymorphism of Folate Metabolism Genes among Ethnic Kazakh Women with Preeclampsia in Kazakhstan: A Descriptive Study.

Preeclampsia is a severe multifactorial complication of pregnancy. Studies found associations between folate metabolism genes' polymorphisms and preeclampsia. However, investigations in this field are limited among Asian populations. Thus, the study's aim was to evaluate the prevalence of methionine synthase (MTR), methionine synthase reductase (MTRR), and methylenetetrahydrofolate reductase (MTHFR) genes' polymorphisms among ethnic Kazakh women with preeclampsia. This was a retrospective study involving 4246 patients' data for the period of 2018-2022. Identification of MTR, MTRR, and MTHFR genes' polymorphism was performed via PR-PCR. Peripheral blood samples were obtained for the analyses. In total, 4246 patients' data of Kazakh ethnicity with preeclampsia at >20 weeks gestational age who had undergone an investigation to identify polymorphisms of the folate metabolism pathway genes for the period of 5 years were included in this study. The most common and prevalent mutation was the MTRR A66G polymorphism: 24.5% of all tested patients with preeclampsia had the MTRR A66G polymorphism. It was highest among the 35-39 age group participants. The second most prevalent was the MTHFR C677T polymorphism: 9% of women with preeclampsia had the MTHFR C677T mutation. It was highest among women aged 30-34. There was a rare association of the MTR A2756G mutation with preeclampsia among the study participants. The identified levels of MTRR A66G and MTHFR C677T polymorphisms among the study participants suggest the importance of evaluating MTRR and MTHFR polymorphisms in women with preeclampsia. The role of the MTR A2756G polymorphism in the development of preeclampsia needs to be further investigated.

Direct Molecular Action of Taurine on Hepatic Gene Expression Associated with the Amelioration of Hypercholesterolemia in Rats.

Taurine can ameliorate hypercholesterolemia by facilitating cholesterol efflux and increasing cytochrome P450 7A1 (CYP7A1) without clear underlying molecular mechanisms. This study aims to elucidate the molecular action of taurine in diet-induced hypercholesterolemia. Male Wistar rats were fed a high cholesterol diet containing 5% taurine for 14 days. Three-dimensional primary hepatocytes from rats were exposed to 10 mM taurine for 24 h. Transcriptome analyses of both the liver and hepatocytes were performed using DNA microarray. Taurine significantly decreased serum cholesterol levels and increased hepatic CYP7A1 mRNA levels and transcription rates in rats. Taurine altered the expression of seventy-seven genes in the liver, involving lipid, drug, amino acid metabolism, and gluconeogenesis pathways. The small heterodimer partner (SHP), a transcription factor regulated by taurine, was suppressed. "Network analysis" revealed a negative correlation between the SHP and induction of CYP7A1 and cytochrome P450 8B1 (CYP8B1). However, CYP7A1 and CYP8B1 levels were not altered by taurine in 3D-primary hepatocytes. Venn diagram analyses of the transcriptomes in both hepatocytes and the liver indicated a consistent upregulation of organic anion transporting polypeptide 2 (OATP2) and betaine homocysteine methyltransferase (BHMT). Taurine ameliorated hypercholesterolemia in rats fed a high cholesterol diet by directly enhancing the hepatic expression of BHMT and OATP2, which modulated the SHP and induced CYP7A1 and CYP8B1, thereby promoting cholesterol catabolism and lowering blood cholesterol levels.

Methionine Synthase 2 Represses Stem Cell Maintenance of Arabidopsis thaliana in Response to Salt Stress.

Salt stress represses the growth and development of plants that mainly depend on the continual propagation and differentiation of stem cells. WUSCHEL (WUS)/WUSCHEL-RELATED HOMEOBOX (WOX) family proteins determine stem cell fate in plants under ever-changing environments. It is not yet known how plant stem cell homeostasis is regulated under salt stress. Methionine synthase catalyzes the formation of methionine by methylating homocysteine in the one-carbon metabolism pathway. In this work, we investigated the role of Arabidopsis METHIONINE SYNTHASE 2 (AtMS2) in stem cell homeostasis under salt stress. The results showed that AtMS2 represses the stem cell maintenance of Arabidopsis in response to salt stress. Under normal growth conditions, AtMS2 is mainly localized in the cytoplasm. However, under salt stress, it exhibits significant accumulation in the nucleus. AtMS2 interacts with the WUS/WOX protein, and, together, they repress WUS/WOX expression by binding to its promoter. The mutation in AtMS2 resulted in enhanced salt tolerance. Therefore, AtMS2 might act as a key negative regulator to repress the stem cell maintenance and growth of Arabidopsis under salt stress.

The role of single nucleotide variants of folate cycle genes of a mother with epilepsy in the occurrence of congenital malformations of the fetus

Aim - To study the frequency of single-nucleotide variants (ONV) rs1801133 and rs1801131 of the MTHFR gene; rs1801394 of the MTRR gene, rs1805087 of the MTR gene and rs1051266 of the SLC19A1 gene in women with epilepsy and to evaluate their associations with major congenital malformations (MCM) of the fetus. Material and methods. The study included 61 women with epilepsy who have children: 20 had different fetal MCM (main group), 41 patients had children born without MCM (comparison group). DNA was extracted from blood, and the genotyping of five ONV into four genes was analyzed by polymerase chain reaction. The frequencies of genotypes and alleles in the mothers of the main and the comparison group were determined, the differences were assessed using Pearson's chi-squared criterion (χ2) and Fisher's exact criterion. Results. There were no statistically significant differences in the frequencies of genotypes and alleles for all analyzed ONV between the main group and the comparison group. There were no statistically significant differences in the frequencies of genotypes and alleles of ONV genes of the folate cycle in mothers of children with malformations (n = 14) and without malformations (n = 22), taking valproic acid. A statistically significant relationship was revealed between the carrier of a certain haplogroup of the mother and the formation of fetal MCM. Conclusion. The MCM in a child is a multifactorial phenomenon in which genetic factors with a small effect size can play a significant role only in the case of certain unfavorable combinations.

Betaine alleviates nonalcoholic fatty liver disease (NAFLD) via a manner involving BHMT/FTO/m6A/ PGC1α signaling

Nonalcoholic fatty liver disease (NAFLD) has emerged as a major public health crisis with significant health threats and economic burdens worldwide in the past decades. Betaine, a naturally occurring alkaloid compound present in various dietary sources including spinach and beets, has been shown to ameliorate hepatic lipid metabolism and attenuate NAFLD, while the underlying mechanism remains elusive. Here, we propose a novel mechanism through which betaine exerts its protective effects against hepatic lipid accumulation and NAFLD from an epigenetics perspective. Specifically, we discover that betaine upregulates betaine homocysteine S-methyltransferase (BHMT) expression, leading to increased nicotinamide adenine dinucleotide phosphate (NADPH) production and subsequent upregulation of fat mass and obesity-associated protein (FTO) expression. Increased abundance of FTO targets peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC1α) mRNA and reduces the N6-methyladenosine (m6A) level in the CDS of Ppargc1α transcript, which positively regulates PGC1α expression and subsequently inhibits hepatic lipid accumulation. Overall, our works demonstrate that betaine may be a promising therapeutic strategy for treating NAFLD and improving liver function through the regulation of NADPH and m6A-mediated pathways.