A Cross-Sectional Study of Dietary and Genetic Predictors of Blood Folate Levels in Healthy Young Adults

In the context of the triple burden of malnutrition: A systematic review of gene-diet interactions and nutritional status

Genetic background interacts with dietary components to modulate nutritional health status. This study aimed to review the evidence for gene-diet interactions in all forms of malnutrition. A comprehensive systematic literature search was conducted through April 2021 to identify observational and intervention studies reporting the effects of gene-diet interactions in over-nutrition, under-nutrition and micronutrient status. Risk of publication bias was assessed using the Quality Criteria Checklist and a tool specifically designed for gene-diet interaction research. 167 studies from 27 populations were included. The majority of studies investigated single nucleotide polymorphisms (SNPs) in overnutrition (n = 158). Diets rich in whole grains, vegetables, fruits and low in total and saturated fats, such as Mediterranean and DASH diets, showed promising effects for reducing obesity risk among individuals who had higher genetic risk scores for obesity, particularly the risk alleles carriers of FTO rs9939609, rs1121980 and rs1421085. Other SNPs in MC4R, PPARG and APOA5 genes were also commonly studied for interaction with diet on overnutrition though findings were inconclusive. Only limited data were found related to undernutrition (n = 1) and micronutrient status (n = 9). The findings on gene-diet interactions in this review highlight the importance of personalized nutrition, and more research on undernutrition and micronutrient status is warranted.

Levels of Folate and Vitamin B12, and Genetic Polymorphisms Involved in One-Carbon Metabolism May Increase the Risk of Cervical Cytological Abnormalities

To analyze the association of cervical cytological abnormalities with genetic polymorphisms of enzymes involved in folate metabolism, and the effect of micronutrients on association of polymorphisms with cervical carcinogenesis. Our samples were divided in Control (120 women with normal cytology), and Cases: 37 women with Atypical Squamous Cells of Undetermined Significance(ASC-US), 33 participants presenting Low-Grade Squamous Intraepithelial Lesion(LSIL), and 24 women presenting High-Grade cervical lesions(HSIL/ASC-H). We obtained cervical samples for cytological analysis, HPV detection, and analysis of polymorphisms and cervical cell folate. Blood samples were obtained for serum folate and vitamin B12 evaluation. To analyze all polymorphisms simultaneously, we calculated Genetic Risk Score(GRS). Median concentrations were used as cutoff for determination of micronutrient levels. We observed no differences of genotype or allelic frequencies of polymorphisms according to cervical lesions. However, high levels of cervical cell folate and high number of genetic alterations increased risk of High-Grade lesions [OR(IC95%):1.85(0.42-8.11)]. Instead, women with vitamin B12 ≤ 274 pg/ml and GRS ≥ 3 presented even greater risk of HSIL/ASC-H [OR(IC95%):2.91(0.46-18.62)]. High frequency of genetic polymorphisms involved in one-carbon metabolism associated with high levels of cell folate or low levels of serum vitamin B12, increased the risk of High-Grade lesion in uterine cervix.

Depression and Vegetarians: Association between Dietary Vitamin B6, B12 and Folate Intake and Global and Subcortical Brain Volumes

Deficiency of vitamin B6 and vitamin B12, mostly in vegetarians, is found to be associated with depression and adverse neurological function. We investigated whether vitamin B6, B12, and folate have an effect on brain structure, especially among depressed people who follow a specific diet. The study sample comprised 9426 participants from the UK Biobank cohort with a mean age of 62.4 years. A generalized linear model controlling for age, sex, body mass index, ethnicity, town send deprivation index, educational qualification, smoking, and alcohol intake was used to test the association between study groups and structural brain volumes. Depression was more prevalent, and intake of vitamin B6 and B12 was lower among vegetarians, while non-vegetarians had a lower intake of folate. Overall, no significant association was observed between vitamin B6, B12, and folate intakes and both global and subcortical brain volumes among participants with depression. However, vitamin B12 intake was positively associated with right pallidum among non-depressed participants, and a significant interaction between vitamin B12 intake and depression status on the right pallidum was observed. Also, a significant interaction between folate intake and depression status on grey matter (GM) volume and left thalamus was observed. Upon diet stratification, folate intake is associated with total brain volume and GM volume among vegetarians with depression. Furthermore, no significant associations were observed for subcortical regions. Our findings suggest that dietary intake of vitamin B6 and B12 might have an effect on brain structure. Vegetarians, particularly those who suffer from depression may benefit from supplementing their diets with vitamins B6, B12, and folate to ensure brain health. Further studies, especially with a larger sample size and longitudinal design, are needed to confirm these findings.

Genetic markers of One-Carbon Metabolism Disorders in Schizophrenial

The paper presents the results of the literature review and the authors’ own studies of the association of several several single-nucleotide genetic polymorphisms (SNP), which affect one-carbon metabolism, with a risk of schizophrenia and the severity of some clusters of its symptoms. Directions for further study of the role of a number of SNP of enzymes in the folate metabolism cycle and related biochemical processes in schizophrenia (in particular, their influence on the effect of personalized correction of one-carbon metabolism disorders) are determined.

Interactions between serum folate and human papillomavirus with cervical intraepithelial neoplasia risk in a Chinese population-based study

Background

Although folate deficiency has long been implicated in cancer development, uncertainties remain concerning its role in cervical cancer prevention. In particular, the interaction between human papillomavirus (HPV) and folate in the risk of cervical intraepithelial neoplasia (CIN) has been little studied.

Objective

The goal of this study was to evaluate the dose-response association of serum folate with the risk of CIN, and the potential for HPV to modify the risk of CIN.

Design

We performed a cross-sectional analysis of screening data in 2304 women aged 19-65 y who participated in an ongoing cohort of 40,000 women in China. Both categoric and spline analyses were used to evaluate the dose-response relation between serum folate and CIN risk.

Results

After adjusting for potential confounders, a statistically significant inverse association between serum folate concentration and at least grade 2 CIN (CIN2+) risk was observed (1st quartile compared with 4th quartile: OR = 1.40; 95% CI: 1.09, 1.79; P-trend < 0.01); however, serum folate concentration was not associated with CIN1 risk. The risk patterns are similar when limited to only CIN2 and CIN3. An inverse linear relation between increased serum folate concentration and the risk of higher-grade CIN (CIN2, CIN3, and CIN2+) was also observed (for CIN2+: P-overall < 0.01, P-nonlinearity = 0.96). The highest risk of CIN2+ was observed in women with high-risk HPV types, who also had the lowest serum folate concentrations (P-interaction < 0.01).

Conclusions

Our study indicates that serum folate is inversely associated with the risk of higher-grade CIN in Chinese women either with or without high-risk HPV infection. Thus, maintenance of normal serum folate levels may prove important for reducing the risk of CIN in women.