bims-vitmet Biomed News
on Vitamin metabolism
Issue of 2025–08–10
eight papers selected by
Onurkan Karabulut, Berkeley City College



  1. Clin Transl Gastroenterol. 2025 Aug 04.
       OBJECTIVES: Vitamin intake may reduce gastrointestinal cancer risk, but how vitamin metabolism genetic polymorphisms affect this association remains unclarified. This meta-analysis examined whether vitamin metabolism genetic polymorphisms influence the association between dietary and circulating vitamins and risk of gastrointestinal cancers.
    METHODS: Literature search was conducted to gather studies investigating the associations between vitamins, genetic polymorphisms, and gastrointestinal cancer risk. Statistical analyses were conducted using "meta" package in R.
    RESULTS: Our meta-analysis incorporated 64 studies on colorectal cancer (CRC), gastric cancer, and esophageal cancer, focusing on vitamin B and vitamin D. High dietary intake of vitamin B was significantly associated with reduced gastrointestinal cancer risk (odds ratio [OR]=0.84, 95% confidence interval [CI]: 0.79-0.90), as was its circulating level (OR=0.53, 95%CI: 0.36-0.78). Individuals harboring the MTHFR 1298AA/AC and CC genotypes demonstrated varying association of CRC risk with dietary vitamin B intake (P-het=0.04), while the significant inverse association of circulating vitamin B with CRC risk was found only for MTHFR 677TT carriers (OR=0.57, 95%CI: 0.33-0.97), but not for the CC/CT genotype (OR=0.98, 95%CI: 0.80-1.21, P-het=0.06). High dietary (OR=0.69, 95%CI: 0.53-0.90) and circulating vitamin D levels (OR=0.74, 95%CI: 0.59-0.94) significantly lowered gastrointestinal cancer risk. The inverse association between circulating vitamin D and CRC risk was exclusively yielded for VDR TaqI Tt/tt carriers (OR=0.52, 95%CI: 0.28-0.95), other than the TT genotype (OR=0.91, 95%CI: 0.70-1.19, P-het=0.10).
    CONCLUSION: High dietary and circulating vitamin B and vitamin D levels were associated with lowered gastrointestinal cancer risk, and the associations may be modified by certain genetic variations in vitamin metabolism pathways.
    Keywords:  Gastrointestinal cancer; Genetic polymorphisms; Systematic Review; Vitamin
    DOI:  https://doi.org/10.14309/ctg.0000000000000899
  2. S Afr Fam Pract (2004). 2025 Jul 14. 67(1): e1-e7
      Vitamin C (ascorbic acid or ascorbate) plays an important role in regulating the health of the skin, promoting the differentiation of epithelial skin cells (keratinocytes) while contributing a notable role in the reduction of melanin synthesis, leading to antioxidative protection against solar-related skin damage. Vitamin C is only sourced from diet because humans have no ability to synthesise it in vivo. Routine dietary intake choices become key in maintaining the skin's integrity, preventing and treating some of the skin conditions encountered regularly by general practitioners and skin specialists alike. There is a strong association between vitamin C and the ageing process, skin pigmentation, control of certain skin diseases and a role in some skin cancers through antioxidation properties. Literature suggests that topical application of vitamin C in different forms of formulations has been demonstrated to have more clinical effect than oral intake.Contribution: This article spotlights the benefits of a vitamin commonly encountered in topical pharmaceutics, ingested as tablets or as part of our routine diet.
    Keywords:  UV radiation; ageing; antioxidant; ascorbic acid; diet; skin application; vitamin C; vitamin E
    DOI:  https://doi.org/10.4102/safp.v67i1.6098
  3. Front Endocrinol (Lausanne). 2025 ;16 1585859
       Introduction: Vitamin D is a pleiotropic hormone essential for bone health and overall physiological function. Despite its significance, vitamin D deficiency remains widespread and is often influenced by genetic factors.
    Methods: This study investigates the role of SDR42E1, a gene encoding a short-chain dehydrogenase/reductase enzyme, in vitamin D regulation and sterol metabolism. Using CRISPR/Cas9 gene-editing, we generated an SDR42E1 knock-in model in HCT116 colorectal cells, which exhibit high endogenous SDR42E1 expression, harboring a nonsense variant associated with vitamin D deficiency.
    Results: Integrated transcriptomic and proteomic analyses revealed significant dysregulation of sterol absorption and metabolism (fold change (FC) = 1.8, P = 0.007) and cancer-related signaling pathways (FC = -1.7, P = 0.02). Notably, key differentially expressed genes included upregulated LRP1B and ABCC2, alongside downregulated WNT16 and SLC7A5. Proteomic profiling confirmed alterations in cell proliferation-related proteins, including reduced ALDOA expression (FC = -0.37, P = 0.0005). Functionally, SDR42E1 deficiency reduced cell viability by 53% (P = 0.0001), an effect reversed by transient SDR42E1 overexpression with restoring ABCC2 expression.
    Conclusion: These findings establish SDR42E1 as a key modulator of vitamin D-related pathways and highlight its potential as a therapeutic target for addressing vitamin D deficiency and associated pathologies, including cancer.
    Keywords:  SDR42E1; endocrine disorders; genetics in endocrinology; precision medicine; vitamin D regulation
    DOI:  https://doi.org/10.3389/fendo.2025.1585859
  4. Sci Rep. 2025 Aug 03. 15(1): 28315
      Patients with celiac disease are at risk of micronutrient deficiencies due to long-term inflammation of the small intestine. Therefore, our aim was to investigate the correlation between CeD and micronutrients. A cross-sectional study enrolled a total of 59 newly diagnosed celiac patients and 59 controls. Levels of 17 vitamins and 10 trace elements were measured. Symptoms, serum IgA anti-TG2 (tTG-IgA), BMI, albumin, hemoglobin, and Marsh classification were recorded. The levels of micronutrients were compared between cases and controls, and correlations between micronutrients and other factors were analyzed. Celiac patients had lower levels of BMI, albumin, hemoglobin, vitamins A, E, K2 (MK-7, MK-4), B6, and B7, as well as zinc, and higher levels of vitamin B3 and chromium than controls (p < 0.05). The deficiency rates of vitamins A, E, and K2 (MK-7) and the excess rate of vitamin B3 were significantly higher than in controls (p < 0.05). Vitamin C, iron and calcium levels were negatively correlated with Marsh classification, while vitamin D and E levels were negatively correlated with serum tTG-IgA levels (p < 0.05). The vitamin A level in classical patients was lower than in non-classical patients (p < 0.01). In conclusion, micronutrient imbalance is very common in celiac patients, including both deficiencies and excesses. Therefore, it is necessary to assess micronutrient levels in newly diagnosed celiac patients.
    Keywords:  Celiac disease; Intestinal inflammation; Nutrients; Trace elements; Vitamins
    DOI:  https://doi.org/10.1038/s41598-025-12631-1
  5. Trends Cardiovasc Med. 2025 Aug 06. pii: S1050-1738(25)00104-5. [Epub ahead of print]
      We summarize the existing literature of randomized controlled trials and meta-analyses related to the effects of calcium and/or vitamin D supplementation on cardiovascular disease outcomes. Despite significant epidemiologic data associating abnormal calcium or vitamin D levels with cardiovascular disease risk, no consistent signal has emerged from the interventional literature for a causal relationship between supplementation of these micronutrients and improved cardiovascular outcomes. There is some evidence to support increased risk of coronary heart disease with calcium supplementation alone, and the effects of vitamin D supplementation on cardiovascular disease appear to be neutral. Overall, there is no evidence to support the routine use of calcium or vitamin D supplementation for the purposes of improving cardiovascular health.
    Keywords:  Calcium; Vitamin D; cardiovascular disease; supplementation
    DOI:  https://doi.org/10.1016/j.tcm.2025.07.012
  6. Nutr Cancer. 2025 Aug 07. 1-24
      Glioma is the most common primary brain tumor, accounting for approximately 70% of adult brain malignancies. Although this cancer is relatively rare, it causes significant mortality. Among environmental risk factors, frequent exposure to ionizing radiation has significantly increased the risk of glioma. Special attention has been paid to diet and dietary factors in recent decades. Although the role of diet in some cancers has been confirmed in previous studies, the link between dietary intake, the immune system, and glioma is still questionable. In the current review, a higher dietary intake of vitamin C, folate, vitamin A, phytochemicals, and calcium might be associated with immune system activation and reduced risk of glioma. In addition, adherence to a high-carbohydrate diet is associated with a high risk of glioma. Despite the evidence, limited data are available for some important fatty acids, B vitamins, protein, vitamins D, E, K, magnesium, copper, zinc, iron, and selenium, and some healthy dietary patterns regarding glioma risk. In terms of clinical outcomes, the ketogenic diet might play a role in the management of glioma and might be used as an adjunctive therapy in these patients. Although observational studies have shown that a higher dietary intake of folate, vitamin C, calcium, and vitamin A was associated with the activation of the immune system and reduced risk of glioma, the complex interactions between diet, immune system, and glioma on the clinical outcomes of patients with glioma have not been investigated. Therefore, further studies are needed in this regard.
    DOI:  https://doi.org/10.1080/01635581.2025.2539538
  7. Clin Exp Pediatr. 2025 Jul 08.
       Background: Homocysteine metabolism is crucial to maintaining vascular and metabolic homeostasis, yet its dysregulation in pediatric β-thalassemia major (β-TM) remains poorly understood.
    Purpose: This study investigated the prevalence and determinants of hyperhomocysteinemia in pediatric β-TM with a focus on vitamin B9 (folate), B12, and B6 deficiencies, oxidative stress marker levels, and the impact of splenectomy.
    Methods: A cross-sectional study was conducted of 92 pediatric β-TM patients. Levels of plasma homocysteine, vitamins B9, B12, and B6, and oxidative stress marker (protein carbonyls, thiols, nitrotyrosine, and nitric oxide metabolites) levels were measured. The patients were grouped based on their splenectomy status. The MTHFR C677T polymorphism was genotyped in a subset of patients (n=39). The statistical analyses included t tests, analysis of variance, Pearson's correlation, and multivariate regression.
    Results: Overall, 93% of patients had hyperhomocysteinemia (≥15 µM), with the values of 50% exceeding 30 µM. Homocysteine levels were negatively correlated with folate levels (r=-0.22, P=0.03) and weakly correlated with B12 levels (r=-0.18, P=0.08). Vitamin B6 levels were not significantly associated with homocysteine levels. Postsplenectomy, patients had significantly higher homocysteine levels (43.3 µM vs. 32.3 µM, P=0.002) but lower nitrotyrosine levels (P=0.035), suggesting reduced nitrative stress. The MTHFR C677T genotype did not significantly influence homocysteine levels in our cohort.
    Conclusion: Hyperhomocysteinemia is prevalent in pediatric β-TM, driven primarily by severe folate and B12 deficiencies. Splenectomy exacerbates hyperhomocysteinemia but reduces nitrative stress, indicating complex metabolic shifts postsplenectomy. These findings highlight the need for routine homocysteine monitoring and targeted vitamin supplementation to mitigate the potential vascular risks of pediatric thalassemia.
    Keywords:  Folate; Homocysteine; Oxidative stress; Splenectomy; Thalassemia; Vitamin B
    DOI:  https://doi.org/10.3345/cep.2025.00556
  8. Front Nutr. 2025 ;12 1644649
       Background: Ulcerative colitis (UC) is a chronic inflammatory bowel disease with increasing global prevalence, making it a significant health concern. Although vitamin A (VA) plays a beneficial role in UC management, its therapeutic efficacy is limited by impaired absorption and disrupted retinoic acid (RA) metabolism. Gut microbiota are known to influence VA metabolic pathways, offering potential targets to enhance VA bioavailability and efficacy.
    Methods: A dextran sulphate sodium (DSS)-induced mouse model of colitis was established to evaluate the therapeutic effects of co-administering Bifidobacterium longum subsp. infantis CCFM1426 with vitamin A. Body weight, disease activity index (DAI) and colon length were monitored in mice with DSS-induced colitis. Serum levels of intestinal injury markers, inflammatory cytokines, antioxidant enzymes and colonic RA levels were measured using ELISA kits. Metagenomic analysis investigated gut microbiota composition.
    Results: It was indicated that the VA and CCFM1426 combination significantly improved colon length and DAI, enhanced serum levels of intestinal injury markers (lipopolysaccharide-binding protein, intestinal fatty acid-binding protein, diamine oxidase) and cytokines (IL-6, TNF-α, IL-10), and restored antioxidant capacity. The combination demonstrated superior efficacy in colonic RA levels and contributed to gut microbiota diversity restoration. Metabolomics analysis showed that colitis mice treated with the combination had higher levels of eicosapentaenoic acid, adenosine and anandamide.
    Conclusion: These findings provide novel evidence that co-administration of CCFM1426 and VA synergistically alleviates colitis by enhancing RA bioavailability through microbiota-dependent pathways.
    Keywords:  Bifidobacterium longum subsp. infantis; gut microbiota; retinoic acid; ulcerative colitis; vitamin A
    DOI:  https://doi.org/10.3389/fnut.2025.1644649