The relationship between plasma homocysteine levels and MTHFR gene variation, age, and sex in Northeast China

Vitamin Metabolism and Its Dependency on Genetic Variations Among Healthy Adults: A Systematic Review for Precision Nutrition Strategies

BACKGROUND/OBJECTIVES

In recent years, there has been a growing interest in precision nutrition and its potential for disease prevention. Differences in individual responses to diet, especially among populations of different ancestry, have underlined the importance of understanding the effects of genetic variations on nutrient intake (nutrigenomics). Since humans generally cannot synthesize essential vitamins, the maintenance of healthy bodily functions depends on dietary vitamin intake. Understanding the differences in vitamin uptake and metabolism across diverse populations may allow for targeted treatment plans and improved overall health. We assessed the current scientific evidence on genetic variations (such as single-nucleotide polymorphisms (SNPs)) affecting vitamin metabolism in humans.

METHODS

A systematic literature review of primary studies on genetic variations associated with (personalized) nutrition was conducted. Using key terms related to personalized nutrition, nutrigenomics, SNPs, and genetic variations, three online databases were searched for studies published between 2007 and 2023 that included healthy adult subjects. Only results that were confirmed at least once were included. Study quality was assessed with the Joanna Briggs Institute (JBI) critical appraisal tool.

RESULTS

Eighty-six articles were included in this review. Our analysis revealed associations with homocysteine metabolism and B Vitamins, Vitamin D, and components of Vitamin E. Genetic associations with Vitamin D, particularly with the GC gene, were extensively researched and linked to lower 25(OH)D concentrations, with sunlight exposure as a contributing factor. Most variants had a negative effect on homocysteine levels. Additionally, we observed general increases in carotenoid levels in the presence of SNPs, although more research on Selenium and Selenoprotein P concentrations is warranted. No studies on Vitamin C were obtained, indicating an area for further methodological improvement. Ancestry is believed to be a significant factor influencing SNP associations and significance.

CONCLUSIONS

The current review emphasizes the importance of genetics in targeted disease prevention and health care. Our comprehensive findings may provide healthcare practitioners with reliable information to make recommendations in precision nutrition, specifically vitamin supplementation.

Investigating the Matrix of Factor V Leiden (G1691A), Factor II Prothrombin (G2021A), MTHFR C677T and A1298G Polymorphisms in Greek Population: A Preliminary Study

BACKGROUND

Thrombophilia, characterized by an increased risk of thrombosis, can result from genetic polymorphisms in clotting factors. This study aims to investigate the prevalence of factor V Leiden (G1691A), factor II prothrombin (G20210A), and MTHFR (C677T and A1298C) polymorphisms in a Greek population, evaluating not only their association with thrombophilia, but also broader health implications.

METHODS

We conducted a cross-sectional study involving one hundred apparently healthy adults from Thessaloniki, Greece. After obtaining informed consent, DNA was isolated and analyzed using real-time PCR to detect the frequencies of the aforementioned polymorphisms.

RESULTS

The genetic distribution of the examined polymorphisms aligns closely with that observed in Northern Europe. Factor V Leiden (FVL) and prothrombin G20210A mutations were predominantly wild types, with a small percentage showing heterozygous mutations. The MTHFR C677T and A1298C polymorphisms showed a higher variation in allele frequency. Certain lifestyle factors such as smoking and high body mass index were significantly associated with the occurrence of combined MTHFR genotypes, suggesting an interaction between genetic and environmental risk factors. Family cancer and cardiovascular history was significantly associated with combined FVL and prothrombin G20210A and MTHFR polymorphism heterozygous carriers.

CONCLUSIONS

Our findings indicate that these genetic polymorphisms are not only pivotal in understanding thrombophilia but also have broader implications for cardiovascular disease and cancer. This study highlights the need for further research into the combined effects of genetic and epigenetic factors on health, which could lead to improved screening and personalized preventive healthcare strategies.

Serum Homocysteine Level Is Positively Correlated With Serum Uric Acid Level in U.S. Adolescents: A Cross Sectional Study

Background

Physiologically, the levels of homocysteine (Hcy) and serum uric acid (SUA) are closely related; however, clinical studies on the relationship between Hcy and SUA have drawn different conclusions and have not analyzed this association among adolescents. This study therefore aimed to evaluate the relationship between Hcy and SUA levels among adolescents.

Methods

In this study, we performed a cross-sectional analysis of data from the National Health and Nutrition Examination Survey for the period 1999–2006, which included 5,404 adolescents aged 12–19 years. An elevated SUA level was defined as ≥5.5 mg/dL. Multivariate logistic regression and multivariate linear regression models were also applied in this study.

Results

The mean concentrations of Hcy and SUA were 6.0 μmol/L and 5.0 mg/dL, respectively, and 33.6% of the participants had SUA levels of ≥5.5 mg/dL. There was a dose–response relationship between Hcy and SUA, and Hcy was linearly positively correlated with SUA. The β value [95% confidence interval (CI)] for SUA in the fully adjusted model was1.43 (95% CI: 1.18, 1.68). The multivariate logistic regression model showed that per 1 increment in log-transformed Hcy, the risk of elevated SUA levels increased by 8.80 times (odds ratio, 8.80, 95% CI: 4.25, 18.20). Subgroup analyses showed that the relationship between Hcy and SUA was significantly different according to sex, age, body mass index (BMI), and estimated glomerular filtration rate (eGFR) stratification (P for interaction <0.05).

Conclusion

Hcy levels were positively correlated with SUA levels and elevated SUA levels among U.S. teenagers, and this effect was more significant among boys aged ≥17 years and among people with lower BMI and eGFR.

Association between plasma homocysteine levels and cognitive deficits in Han Chinese patients with schizophrenia across age groups

It was still unclear how homocysteine (Hcy) levels and cognitive deficits change in patients with schizophrenia of various ages. The present article attempts to assess the relationship between Hcy levels and cognitive deficits in patients with schizophrenia across age groups, especially in young people. Totals of 103 patients and 122 healthy controls were included. All participants were stratified into four groups according to their age: 18-29 years, 30-39 years, 40-49 years, and 50-59 years. Clinical data, plasma Hcy levels, and cognitive function score were collected. Cognitive function was evaluated using the MATRICS Consensus Cognitive Battery of tests assessing speed of processing, verbal learning and memory, visual learning and memory, working memory, and attention/vigilance. Compared with the healthy group, Hcy levels increased significantly, and all the measured cognitive function score were significantly lower in all age groups of patients with schizophrenia (p < 0.001). Hcy levels were negatively associated with speed of processing (SoP), working memory (WM), and visual learning and memory (Vis Lrng) score in 18-29 years. Further multiple regression analysis showed that SoP were independently associated with Hcy levels in patients with schizophrenia aged 18-29 years (B = 0.74, t = 3.12, p = 0.008). Based on our results, patients with schizophrenia performed worse on cognitive assessments and Hcy levels were more closely related to cognition in young patients.

Analysis of the association and predictive value of hyperhomocysteinaemia for obstructive coronary artery disease

Objective

To investigate the predictive value of hyperhomocysteinaemia (HHcy) for obstructive coronary artery disease (CAD) in an Asian population in northern China.

Methods

This retrospective study enrolled patients at their first cardiac assessment and assigned them to an obstructive CAD group or a non-obstructive CAD group according to the coronary angiography results. HHcy was defined as a homocysteine (Hcy) level > 15 µmol/l.

Results

This study enrolled 2987 participants: 1172 in the non-obstructive CAD group and 1815 in the obstructive CAD group. Hcy level in the obstructive CAD group was significantly higher than in the non-obstructive CAD group. The proportion of patients with HHcy in the obstructive CAD group was significantly greater than in the non-obstructive CAD group. Multivariate logistic regression analysis demonstrated that HHcy was independently correlated with obstructive CAD in both young (aged ≤ 55 years) and old patients (aged > 55 years). HHcy showed a higher sensitivity (93.1%), specificity (86.1%) and accuracy (90.0%) for obstructive CAD. The odds ratio for HHcy was 84.2. The Kappa value (0.8) showed substantial agreement between obstructive CAD and HHcy.

Conclusions

HHcy was associated with obstructive CAD and may be a potentially independent risk factor for obstructive CAD with good predictive value.

Gender differences in risk factors for high plasma homocysteine levels based on a retrospective checkup cohort using a generalized estimating equation analysis

Background

Hyperhomocysteinemia (HHcy) is associated with various health problems, but less is known about the gender differences in risk factors for high plasma homocysteine (Hcy) levels.

Methods

In this study, a retrospective study was carried out on 14,911 participants (7838 males and 7073 females) aged 16–102 years who underwent routine checkups between January 2012 and December 2017 in the Health Management Department of Xuanwu Hospital, China. Anthropometric measurements, including body mass index (BMI) and waist-to-hip ratio, were collected. Fasting blood samples were collected to measure the biochemical indexes. The outcome variable was Hcy level, and a generalized estimating equation (GEE) analysis was used to identify the associations of interest based on gender.

Results

Males exhibited increased Hcy levels (16.37 ± 9.66 vs 11.22 ± 4.76 μmol/L) and prevalence of HHcy (37.0% vs 11.3%) compared with females. Hcy levels and HHcy prevalence increased with age in both genders, except for the 16- to 29-year-old group. GEE analysis indicated that irrespective of gender, aspartate aminotransferase, creatinine, uric acid, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels were positively correlated with Hcy levels, and alanine aminotransferase, total cholesterol and glucose were negatively correlated with Hcy levels. However, age, BMI and triglycerides (TGs) were positively correlated with Hcy levels exclusively in females.

Conclusions

Gender differences in risk factors for high plasma Hcy levels were noted. Although common correlational factors existed in both genders, age, BMI and TGs were independent risk factors for Hcy levels specifically in females.

Relationship between the risk factors of cardiovascular disease by testing biochemical markers and young men with erectile dysfunction: a case-control study

Background

Erectile dysfunction (ED) shares common risk factors with cardiovascular disease (CVD), such as diabetes mellitus (DM) and dyslipidemia, but the relationship between the risk factors of CVD in biochemical markers and young men with ED age 20–40 years is not fully clarified.

Methods

A total of 289 ED outpatients (20–40 years old) were allocated under ED group, based on patients’ complaints and physical examinations. According to the frequency matching ratio of 1:4, 1,155 male individuals (20–40 years old) without ED were set as control group. All participants were tested for lipid profiles including total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL), low density lipoprotein (LDL), blood glucose (BG), homocysteine (HCY), liver function including alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and renal function including uric acid (UA) and creatinine (CR). The study was designed to compare the two groups using an established binary logistic regression analysis model. The ED group was then subdivided into a younger ED group (20–30 years old) and an older ED group (31–40 years old) for further comparisons.

Results

After comparison, no obvious differences were found in medians of age, TC, TG, HDL, HCY, UA, and ALT in the two groups. Median LDL, BG, and CR were significantly higher and AST was much lower in the ED group (P<0.01). In binary logistic regression analysis, odds ratios (OR) for LDL, BG, CR, and AST were 1.279, 1.237, 1.026, and 0.978, respectively. The sensitivity value and specificity value were 43.25% and 72.56%, respectively. The medians of LDL, TG, and TC were higher and HDL was much lower in the older ED group, as compared with the younger group (P<0.05). No significant differences were displayed in medians of other biochemical markers in the above comparisons.

Conclusions

Elevated LDL, BG, and CR were related factors of ED in young men. Lipid profile was significantly different between young men with ED aged 20–30 and 31–40 years.

Serum homocysteine levels and their association with clinical characteristics of inflammatory arthritis

OBJECTIVE

The aim of our study was to explore the serum levels of homocysteine (Hcy) and its association with clinical characteristics in patients with different types of inflammatory arthritis.

METHODS

A total of 242 patients diagnosed with inflammatory arthritis (which included rheumatoid arthritis (RA), ankylosing spondylitis (AS), and gout), 49 with osteoarthritis (OA), and 36 with hyperuricaemia (HUA) and 81 healthy controls (HCs) were enrolled for comparisons.

RESULTS

The serum Hcy levels of patients with RA, AS, and OA were comparable with those of the HC group (P > 0.05). However, the serum level of Hcy was significantly higher in patients with gout than in HCs (18.75 ± 9.98 vs. 14.20 ± 6.22 μmol/L, P = 0.007). In addition, we found that the serum Hcy level was much higher in RA patients who received methotrexate (MTX) therapy without folic acid supplementation than in those who received MTX with folic acid supplementation (13.39 ± 4.80 vs. 9.41 ± 2.04 μmol/L, P = 0.001). Furthermore, there was a positive correlation between uric acid and Hcy in patients without uric acid-lowering treatment (r = 0.537, P = 0.002), but the correlation was eliminated after adjusting uric acid-lowering treatment (r = 0.139, P = 0.393). Finally, consistent with the above findings, hyperhomocysteinaemia (HHcy) was more common in gout patients (P < 0.05).

CONCLUSION

Screening for HHcy in patients with gout and RA, especially RA patients treated with MTX, might be necessary, and patients with HHcy might benefit from earlier supplementation with folic acid. Key Points • Serum homocysteine (Hcy) was elevated and the rate of hyperhomocysteinaemia (HHcy) was significantly higher in gout. • Rheumatoid arthritis (RA) patients who received methotrexate (MTX) treatment without folic acid supplementation showed higher serum Hcy than those who received MTX treatment with folic acid supplementation. • The serum Hcy level was positively correlated with age in only RA patients. • Serum Hcy was correlated with uric acid in gout patients, but the correlation was eliminated after adjusting uric acid-lowering treatment.

Isolated cortical vein thrombosis after nitrous oxide use in a young woman: a case report

Background

Nitrous oxide has become a popular inhalant as abused substance by young Chinese people in recent years. It has been mainly associated with medical conditions including megaloblastic anemia and myeloneuropathy.

Case presentation

We report a case of a 25-year-old high school graduate who had been abusing nitrous oxide for twenty months. She had a history of peripheral neuropathy and subacute combined degeneration in between. The young woman presented with headache, motor aphasia and right arm paralysis of eight hours after intermittently consuming nitrous oxide for one week. D-dimer was increased (1.1 mg/ml). Blood vitamin B12, folate, homocysteine and beta-HCG levels were normal. Head CT showed hemorrhagic infarction and subarachnoid hemorrhage. MR angiography and venography were normal. Head MRI identified left frontal isolated cortical vein thrombosis. Her muscle strength and verbal fluency significantly improved after initiation of Low Molecular Weight Heparin and serial head MRI showed continuous reduction in the size of thrombus.

Conclusions

For the first time nitrous oxide use is found to be related to isolated cortical vein thrombosis. Public education regarding the potential consequences of abusing nitrous oxide especially in high-risk individuals is urgently needed.