Genetic variants of folate metabolism and the risk of multiple sclerosis

BACKGROUND AND AIMS

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) of unknown cause. Alterations in one-carbon metabolism have impact in the pathophysiology by genetic susceptibility to MS and increased the risk of MS. The aim of this study was to investigate the contribution of the gene polymorphism on Methylenetetrahydrofolate Reductase (MTHFR), Methionine Synthase Reductase (MTRR), Methionine Synthase (MTR) enzymes and of the essential factors (homocysteine, Hcy; cysteine, Cys; and vitamin B12, VitB12) in folate metabolism.

METHODS

Eligible MS patients (n = 147) and health controls (n = 127) were participated. The gene polymorphisms were analyzed by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and the levels of plasma Hcy, Cys and VitB12 were measured by Enzyme Linked Immunuabsorbent Assay (ELISA).

RESULTS AND CONCLUSION

Our results showed that the levels of Hcy and VitB12 were lower and the levels of Cys were higher in MS compared to controls. The observation of high Cys values in all 3 gene polymorphisms suggests that the transsulfiration pathway of Hcy is directed towards Cys formation since the methionine synthesis pathway does not work. We could not find any association with all gene polymorphisms with the risk of MS. The T allele of MTHFR C677T and G allele of MTR A2756G are risk factors for serum Cys level on MS. As for MTR A2756G, serum vitB12 was observed in MS patients with G allele.

[Relationship between vitamin B12, iron, folic acid, homocystein and vitamin D3 serum levels in orofacial sicca and/or Sjögren's syndrome in a Hungarian patient population]

Bevezetés: A D3-, a B12-vitamin, a folsav és a vas hiánya önmagában is okozhat orofacialis sicca tüneteket: szem- és szájszárazságot, glossitist, szájégést, amellett a nyálkahártya atrophiáját, gyulladását, illetve mindezeket súlyosbíthatja. Kevés az ismeret azonban a fenti laboratóriumi paramétereknek, valamint a homociszteinnek a szintjeiről szájszárazságban szenvedők, valamint a könnymirigyek és a nyálmirigyek autoimmun gyulladásával járó Sjögren-szindróma esetében. Autoimmun betegségekben a D3-vitamin szintje alacsonyabb az egészségesekénél, és szisztémás lupus erythematosusban, valamint rheumatoid arthritisben ez összefügg a betegség aktivitásával. A siccatünetekhez társuló nyelőcső- és gyomornyálkahártya-elváltozások pedig egyéb általános tüneteket okozhatnak, befolyásolhatják az étkezést és a tápanyagok felszívódását. Célkitűzés: A szerzők célja volt meghatározni, hogy a hazai, szájszárazságban és/vagy Sjögren-szindrómában szenvedők esetében kimutatható-e különbség a D3-, a B12-vitamin-, a folsav-, a homocisztein-, valamint a vasanyagcsere-értékek szérumszintjében az egészséges kontrollok értékeihez képest. Módszer: A szubjektív siccatüneteket (xerostomia, xerophthalmia) meghatározó kérdőíves felmérés, valamint a hyposalivatiót igazoló sialometria, majd a Sjögren-szindróma irányában történő kivizsgálás (az ACR–EULAR diagnosztikus kritériumrendszer alapján) után a résztvevők 4 csoportot alkottak, ezek: 1. egészséges kontrollok, 2. xerostomia-, 3. hyposalivatio-, 4. Sjögren-szindrómás csoport. Eredmények: A kapott eredmények alapján a hazai Sjögren-szindrómásoknál a D3-vitamin és a vas szérumszintje, a csak hyposalivatióban szenvedők esetében pedig a vas szintje jelentősen csökkent volt (D3-vitamin: 1. csoport: 36,24 ± 20,14 ng/ml, 2. csoport: 47,85 ± 26,84 ng/ml, 3. csoport: 42,04 ± 21,03 ng/ml, 4. csoport: 26,96 ± 7,53 ng/ml, p<0,05; vas: 1. csoport: 16,9 ± 5,10 mmol/l, 2. csoport: 13,6 ± 4,35 mmol/l, 3. csoport: 17,1 ± 9,76 mmol/l, 4. csoport: 13,0 ± 6,64 mmol/l, p<0,05). A B12-vitamin, a transzferrin és transzferrinszaturáció, valamint a folsav és a homocisztein szintje nem mutatott szignifikáns eltérést a szájszárazságban és/vagy Sjögren-szindrómában szenvedők esetében az egészséges kontrollokhoz képest. Megbeszélés és következtetés: Míg a D3-vitamin csökkent szérumszintje az autoimmun gyulladással, addig a vasé inkább a tápcsatorna-nyálkahártya állapotával, azaz a felszívódás zavarával és/vagy a táplálkozási séma változásával lehet összefüggésben, hiszen az első esetben nem, míg a második esetben összefüggés volt kimutatható a csökkent szérumérték és a nyáltermelés csökkenése között is. Orv Hetil. 2024; 165(4): 147–154.

Administration of metformin alleviates atherosclerosis by promoting H2S production via regulating CSE expression

The therapeutic effect of metformin (Met) on atherosclerosis was studied here. Effects of methionine and Met on the induction of inflammatory response and H₂ S expression in peritoneal macrophages were evaluated. Enzyme-linked immunosorbent assay, immunohistochemistry assay, western blot, and quantitative reverse transcription polymerase chain reaction were conducted to observe the levels of cystathionine γ-lyase (CSE), DNA methyltransferases 1 (DNMT1), DNMT3a, DNMT3b, tumor necrosis factor (TNF- α), interleukin 1b (IL-1β), and hydrogen sulfide (H ₂ S). Luciferase and bisulfite sequencing assays were also utilized to evaluate the CSE promoter activity as well as the methylation status of CSE in transfected cells. Methionine significantly elevated Hcy, TNF-a, H ₂ S, and IL-1β expression while decreasing the level of CSE in C57BL/6 mice. In contrary, co-treatment with Methionine and Met reduced the detrimental effect of Methionine. Homocysteine (Hcy) decreased H ₂ S expression while promoting the synthesis of IL-1β and TNF-α in THP-1 and raw264.7 cells. Treatment of THP-1 and raw264.7 cells with methionine and Met reduced the activity of methionine in dose dependently. Moreover, Hcy increased the expression of DNMT and elevated the level of methylation in the CSE promoter, whereas the co-treatment with methionine and Met attenuated the effects of Hcy. Methionine significantly decreased plasma level of CSE while increasing the severity of inflammatory responses and plasma level of Hcy, which in turn suppressed H ₂ S synthesis and enhanced DNA hypermethylation of CSE promoter to promote the pathogenesis of atherosclerosis. In contrary, co-treatment with methionine and Met reduced the detrimental effect of methionine.

Evaluation of homocystein and asymmetric dimethyl arginine levels in patients with coronary slow flow phenomenon

Background

Previous studies have demonstrated that homocysteine and asymmetric dimethyl arginine (ADMA) levels were strongly associated with cardiovascular diseases including coronary artery disease. The aim of this study was to investigate the role of plasma homocysteine and ADMA levels in the pathogenesis of coronary slow flow (CSF) phenomenon.

Methods

Twenty-three patients with CSF and 25 controls with normal coronary flow were included in this study. The quantitative measurement of coronary blood flow was performed using the thrombolysis in myocardial infarction frame count method. Plasma homocysteine and ADMA levels were determined using enzymatic assays from venous blood samples.

Results

The patients with CSF had significantly higher plasma homocysteine levels than controls (16.2 ± 7.6 vs. 12.2 ± 2.2 μM/L; p = 0.023). The uric acid levels were significantly higher in CSF group than controls (5.4 ± 1.1 vs. 4.6 ± 0.9 mg/dl; p = 0.011). Plasma ADMA levels were also higher in the CSF group; however, this was not statistically significant (0.6 ± 0.1 vs. 0.5 ± 0.2 μM/L; p = 0.475).

Conclusions

Increased homocysteine and uric acid levels may play an important role in the pathogenesis of CSF. Further large scale studies are required to determine the relationship between ADMA levels and CSF.

MTHFR gene C677T and A1298C variants are associated with FMF risk in a Turkish cohort

BACKGROUND

Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme in homocysteine (Hcy) metabolism. We aimed to evaluate a possible relationship between MTHFR gene C677T (rs 1801133), A1298C (rs 1801131) variants and susceptibility to FMF in a Turkish cohort.

MATERIAL-METHODS

This case-control study included 198 Turkish FMF patients and 100 healthy subjects as controls. MTHFR C677T and A1298C were analyzed by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) methods.

RESULTS

The genotype distribution and allele frequency of the MTHFR C677T were statistically different between the patients and the control group (P=.006, P=.001, respectively). The frequency of the TT genotype and T allele of MTHFR C677T was significantly higher in the patients than in the controls. The genotype distribution of MTHFR A1298C variant did not show any statistically significant difference between the patients and the controls (P›.05). The patients had statistically different frequencies in allele C of MTHFR A1298C variant compared with the control (P=.032). We also examined the risk associated with inheriting the combined genotypes for the two MTHFR variants. According to these results, individuals who were CC homozygous at C677T locus and AA homozygous at A1298C locus have a lower risk of developing FMF (P=.002). Individuals who were TT homozygous at C677T locus and AC heterozygous at A1298C locus have higher risk of developing FMF (P=.033).

CONCLUSION

Our findings clearly showed there was an association the MTHFR C677T/A1298C variants and susceptibility to FMF in the Turkish sample.

Serum Vitamin B12, Homocysteine and Methylmalonic Acid Levels in Patients With Parenchymal Neuro-Behçet's Syndrome

Objectives

This study aims to investigate the role of serum levels of vitamin B12 (VitB12), homocysteine (Hcy), and methylmalonic acid (MMA) in the development of parenchymal neuro-Behçet's syndrome (NBS) and to compare them with healthy controls and Behçet's syndrome (BS) patients without NBS.

Patients and methods

Serum VitB12, Hcy, and MMA were measured using enzyme-linked immunosorbent assay in 64 patients (36 males, 28 females; mean age 36±8.3 years; range 20 to 56 years) who met the criteria of the International Study Group for Behçet's Disease and 30 matched healthy controls (17 males, 13 females; mean age 35.76±9.6 years; range 20 to 50 years). The study participants were grouped as BS patients with NBS, BS patients without NBS, and healthy controls.

Results

There was no significant difference between the groups regarding serum VitB12, Hcy, and MMA levels (p>0.05). Serum VitB12 levels were below the lower limit and serum Hcy levels were above the upper limit in all participants. MMA levels were normal in all participants. There was no correlation between the serum levels of VitB12, Hcy, and MMA and disease activity (p>0.05).

Conclusion

The results of this study suggest that there is no significant association between VitB12 deficiency and parenchymal NBS. Further studies are needed to investigate the underlying mechanisms of the variable effects of VitB12 deficiency on different clinical manifestations of BS.

5,10-methylene tetrahydrofolate reductase C677T gene polymorphism, homocysteine concentration and the extent of premature coronary artery disease in southern Iran

Elevated level of plasma homocysteine (Hcy) has been identified as an independent risk factor for coronary artery disease (CAD). Furthermore, numerous studies have documented the influences of a common polymorphism (C677T) of methylenetetrahydrofolate reductase (MTHFR) on homocysteine levels. However the relationship between this mutation and cardiovascular diseases (CVD) has remained as a controversial issue. The present study was undertaken to investigate the relationship between C677T polymorphism of MTHFR gene, plasma total Hcy levels and the number of affected vessels as a criterion for the extent of CAD. MTHFR genotypes and plasma homocysteine (HCY) concentrations were examined in 231 patients and 300 healthy subjects who underwent diagnostic coronary angiography. A multiple linear regression analysis was performed to identify the predictors of Hcy levels whereas logistic regression model was built to determine the association of Hcy quartiles with the risk of CAD adjusted for risk factors. The prevalence of MTHFR genotypes was similar between CAD patients and non-CAD individuals while the geometric mean of Hcy values was significantly higher in patient group (14.13 ± 4.11 μmol/l) than in control group (10.19 ± 3.52 μmol/l) (P < 0.001). Moreover, unlike the MTHFR polymorphism, Hcy concentration increased with increasing number of stenosed vessels and the CAD risk increased about 2 folds in the top two Hcy quartiles (≥ 17.03 and 13.20-17.02 μmol/l) compared with the lowest quartile (≤ 9.92 μmol/l) after controlling for conventional risk factors (P<0.001 for both). Our data suggest that hyperhomocysteinaemia (HHcy) is significantly associated to CAD risk increase as well as to the extent of coronary atherosclerosis.

Effects of red grape juice consumption on high density lipoprotein-cholesterol, apolipoprotein AI, apolipoprotein B and homocysteine in healthy human volunteers

It has suggested that grape juice consumption has lipid- lowering effect and it is associated with a decreased risk of heart disease. We aimed to evaluate the effects of red grape juice (RGj) consumption on high density lipoprotein-cholesterol (HDL-C), apolipoprotein AI (apoAI), apolipoprotein B (apoB) and homocysteine (Hcy) levels in healthy human volunteers. Twenty six healthy and nonsmoking males, aged between 25-60 years, who were under no medication asked to consume 150 ml of RGj twice per day for one month. Serum HDL-C, apoAI, apoB and plasma Hcy levels were measured before and after one month RGj consumption. HDL-C levels after RGj consumption were significantly higher than the corresponding levels before the RGj consumption (41.44 ± 4.50 and 44.37 ± 4.30 mg/dl; P<0.0001). Also, apoB was significantly increased after RGj consumption (149.0 ± 22.35 and 157.19 ± 18.60 mg/dl; P<0.002). But apoAI levels were not changed significantly before and after of RGj consumption (154.27 ± 21.55 and 155.35 ± 21.07 mg/dl; P>0.05). Hcy levels were decreased after RGj consumption (7.70 ± 2.80 and 6.20 ± 2.30 µmol/l; P<0.001). The present study demonstrates that RGj consumption can significantly increase serum HDL-C levels and decrease Hcy levels. These findings may have important implications for the prevention of atherosclerosis in healthy individuals.

Oxidative markers, nitric oxide and homocysteine alteration in hypercholesterolimic rats: role of atorvastatine and cinnamon

To investigate the effects of atorvastatin and cinnamon on serum lipid profile, oxidative stress, antioxidant capacity, hepatic enzymes activities, nitric oxide (NO) as well as homocysteine (Hcy) in hypercholesterolemic rats, 48 male albino rats, weighing 130-190 gm were divided into 2 groups, normal group fed on basal rat chow diet (n=12) and high cholesterol group (HCD) were fed on 1% cholesterol-enriched diet for 15 day (n=36). Hypercholesterolemic rats were divided into 3 subgroups (n=12 for each) fed the same diet and treated with atorvastatine (HCD+Atorvastatin) or cinnamon extract (HCD+cinnamon) or none treated (HCD) for 3&6 weeks. Serum triglycerides (TG), Total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), ALT, AST, NO, Hcy, hepatic reduced glutathione (GSH), Malondialdehyde (MDA) and antioxidant enzymes, Superoxide dismutase (SOD) and catalase activity were measured. Results showed that HCD increased significantly TG, TC, LDL-C, ALT, AST, Hcy and hepatic MDA, while lowered significantly antioxidant enzyme activities and NO levels. Atorvastatin therapy significantly increased HDL-C, NO and antioxidant activity while decreased LDL-C, MDA and Hcy concentrations. Serum TG, TC, LDL-C, ALT, AST and hepatic MDA levels were significantly lowered meanwhile, serum HDL, NO values and hepatic antioxidant activities were significantly, higher in cinnamon-treated than untreated group. These results indicate that lipid abnormalities, oxidative injury and hyperhomocystienemia were induced by HCD and this study recommend that administration of atorvastatine or cinnamon provided protection against the lipemic-oxidative disorder and act as hypocholesterolemic, hepatoprotective agent and improve cardiovascular function through modulation of oxidative stress, NO and Hcy.

[Role of homocysteine in the pathogenesis of vascular complications of type 2 diabetes]

The purpose of the investigation was to study the plasma levels of homocysteine (HC) inpatients with type 2 diabetes mellitus (DM2) and its association with the development of diabetic angiopathies and some clinical and laboratory parameters. Among 92 patients with DM2, hyperhomocysteinemia (22.6±6.1 μmol/l) was detected in 53% (Group 1) whereas the level of HC was normal (11.3±2.7 μmol/l). The signs of macro- and microangiopathy (nephropathy, in particular) were more common In patients with elevated HC levels than in those with normal HC levels (70% versus 21%; p <0.001; 73% versus 26%; p = 0.008). The carbohydrate and lipid metabolic values and the type of sugar-reducing therapy did not affect the level of HC whereas a clear correlation was found between HC and glomerular filtration rate(GFR), albuminuria, age, and systolic blood pressure. Thus, elevated plasma HC levels in patients with DM2 are associated with the high risk of vascular events and with renal functional parameters (GFR, albuminuria).

Nodular regenerative hyperplasia, portal vein thrombosis, and avascular hip necrosis due to hyperhomocysteinaemia

A male patient with portal hypertension, portal vein thrombosis, spontaneous splenorenal shunt formation, and encephalopathy, thought to have post-hepatitis B cirrhosis, is described. His condition deteriorated and necessitated liver transplantation. In the explant liver, nodular regenerative hyperplasia with pronounced vascular lesions both in portal venules and in arterioles was found instead of classical cirrhosis. Two years post-transplant he developed bilateral ischaemic femur head necrosis. The three disorders (portal vein thrombosis, nodular regenerative hyperplasia, and ischaemic hip necrosis) seemed to be due to a common vasculopathy induced by hyperhomocyteinaemia. Genetic studies showed that he carried a mutation in the gene encoding for formation of methylenetetrahydrofolate reductase. Treatment with folic acid combined with pyridoxine (vitamin B6) and cyanocobalamin (vitamin B12) normalised his serum homocysteine levels.