Mathematical Modeling of Glutathione Status in Type 2 Diabetics with Vitamin B12 Deficiency

Vitamin B12: prevention of human beings from lethal diseases and its food application

Vitamin B12, a water-soluble essential micronutrient, plays a pivotal role in numerous physiological processes in the human body. This review meticulously examines the structural complexity and the diverse mechanisms through which vitamin B12 exerts its preventive effects against a spectrum of health conditions, including pernicious anaemia, neurological disorders, obesity, diabetes, dyslipidaemia and complications in foetal development. The selection of articles for this review was conducted through a systematic search across multiple scientific databases, including PubMed, Scopus and Web of Science. Criteria for inclusion encompassed relevance to the biochemical impact of vitamin B12 on health, peer-reviewed status and publication within the last decade. Exclusion criteria were non-English articles and studies lacking empirical evidence. This stringent selection process ensured a comprehensive analysis of vitamin B12's multifaceted impact on health, covering its structure, bioavailable forms and mechanisms of action. Clinical studies highlighting its therapeutic potential, applications in food fortification and other utilizations are also discussed, underscoring the nutrient's versatility. This synthesis aims to provide a clear understanding of the integral role of vitamin B12 in maintaining human health and its potential in clinical and nutritional applications. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Potential of postbiotics for the treatment of metabolic disorders

Postbiotics, the next generation of probiotics, are extracts that are free of living and nonviable bacteria and show strong modulatory effects on the gut flora. Examples include vitamin B12, vitamin K, folate, lipopolysaccharides, enzymes, and short-chain fatty acids (SCFAs), representing a subset of essential nutrients commonly found in the human diet. Postbiotics have been observed to demonstrate antiobesity and antidiabetic effects through a variety of mechanisms. These pathways primarily involve an elevation in energy expenditure, a decrease in the formation and differentiation of adipocytes and food intake, modification of lipid and carbohydrate absorption and metabolism, and regulation of gut dysbiosis. Based on these above effects and mechanisms, the use of postbiotics can be considered as potential strategy for the treatment of metabolic disorders.

Vitamin B12-Multifaceted In Vivo Functions and In Vitro Applications

Vitamin B12 plays a key role in DNA stability. Research indicates that vitamin B12 deficiency leads to indirect DNA damage, and vitamin B12 supplementation may reverse this effect. Vitamin B12 acts as a cofactor for enzymes such as methionine synthase and methylmalonyl-CoA mutase, which are involved in DNA methylation and nucleotide synthesis. These processes are essential for DNA replication and transcription, and any impairment can result in genetic instability. In addition, vitamin B12 has antioxidant properties that help protect DNA from damage caused by reactive oxygen species. This protection is achieved by scavenging free radicals and reducing oxidative stress. In addition to their protective functions, cobalamins can also generate DNA-damaging radicals in vitro that can be useful in scientific research. Research is also being conducted on the use of vitamin B12 in medicine as vectors for xenobiotics. In summary, vitamin B12 is an essential micronutrient that plays a vital role in DNA stability. It acts as a cofactor for enzymes involved in the synthesis of nucleotides, has antioxidant properties and has potential value as a generator of DNA-damaging radicals and drug transporters.

Postbiotics as potential new therapeutic agents for metabolic disorders management

The prevalence of obesity, diabetes, non-alcoholic fatty liver disease, and related metabolic disorders has been steadily increasing in the past few decades. Apart from the establishment of caloric restrictions in combination with improved physical activity, there are no effective pharmacological treatments for most metabolic disorders. Many scientific-studies have described various beneficial effects of probiotics in regulating metabolism but others questioned their effectiveness and safety. Postbiotics are defined as preparation of inanimate microorganisms, and/or their components, which determine their safety of use and confers a health benefit to the host. Additionally, unlike probiotics postbiotics do not require stringent production/storage conditions. Recently, many lines of evidence demonstrated that postbiotics may be beneficial in metabolic disorders management via several potential effects including anti-inflammatory, antibacterial, immunomodulatory, anti-carcinogenic, antioxidant, antihypertensive, anti-proliferative, and hypocholesterolaemia properties that enhance both the immune system and intestinal barrier functions by acting directly on specific tissues of the intestinal epithelium, but also on various organs or tissues. In view of the many reports that demonstrated the high biological activity and safety of postbiotics, we summarized in the present review the current findings reporting the beneficial effects of various probiotics derivatives for the management of metabolic disorders and related alterations.

Vitamin B12 enhances the antitumor activity of 1,25-dihydroxyvitamin D3 via activation of caspases and targeting actin cytoskeleton

BACKGROUND

1,25-dihydroxyvitamin D3 (1,25(OH)2D3) is an effective anticancer agent, and when combined with other agents it shows superior activities. Vitamin B12 has been shown to contribute to increasing the effectiveness of anticancer drugs when used in combination. Thus, the current study aimed at investigating the anticancer potential of the combination of 1,25(OH)2D3 and vitamin B12.

METHODS

MTT assay was used to determine the cytotoxic activity of combining 1,25(OH)2D3 and vitamin B12 against six different cancer cell lines and one normal cell line. The surviving fraction after clonogenic assay was measured, and the effects of 1,25(OH)2D3/B12 combination on the activity of different caspases, cell adhesion, actin cytoskeleton, cell morphology, and percentage of polarized cells were evaluated.

RESULTS

Vitamin B12 did not cause cytotoxicity, however, it enhanced the cytotoxicity of 1,25(OH)2D3 against cancer cells. The cytotoxic effects of 1,25(OH)2D3 and its combination with vitamin B12 was not evident in the normal mammary MCF10A cell line indicating cancer cell-specificity. The cytotoxic effects of 1,25(OH)2D3/B12 combination occurred in a dose-dependent manner and was attributed to apoptosis induction which was mediated by caspase 4 and 8. Moreover, 1,25(OH)2D3/B12-treated cells showed enhanced inhibition of clonogenic tumor growth, reduced cell adhesion, reduced cell area, reduced percentage of cell polarization, and disorganized actin cytoskeleton resulting in reduced migratory phenotype when compared to cells treated with 1,25(OH)2D3 alone.

CONCLUSION

1,25(OH)2D3 and vitamin B12 exhibited synergistic anticancer effects against different cancer cell lines. The combination therapy of 1,25(OH)2D3 and vitamin B12 may provide a potential adjunctive treatment option for some cancer types.

Mechanistic Link between Vitamin B12 and Alzheimer’s Disease

Alzheimer’s disease (AD) is the most common form of dementia in the elderly population, affecting over 55 million people worldwide. Histopathological hallmarks of this multifactorial disease are an increased plaque burden and tangles in the brains of affected individuals. Several lines of evidence indicate that B12 hypovitaminosis is linked to AD. In this review, the biochemical pathways involved in AD that are affected by vitamin B12, focusing on APP processing, Aβ fibrillization, Aβ-induced oxidative damage as well as tau hyperphosphorylation and tau aggregation, are summarized. Besides the mechanistic link, an overview of clinical studies utilizing vitamin B supplementation are given, and a potential link between diseases and medication resulting in a reduced vitamin B12 level and AD are discussed. Besides the disease-mediated B12 hypovitaminosis, the reduction in vitamin B12 levels caused by an increasing change in dietary preferences has been gaining in relevance. In particular, vegetarian and vegan diets are associated with vitamin B12 deficiency, and therefore might have potential implications for AD. In conclusion, our review emphasizes the important role of vitamin B12 in AD, which is particularly important, as even in industrialized countries a large proportion of the population might not be sufficiently supplied with vitamin B12.

Serum potassium, albumin and vitamin B12 as potential oxidative stress markers of fungal peritonitis

BACKGROUND

Biomarkers of oxidative stress (OS) have been poorly explored in fungal peritonitis (FP). Potassium is a regulator of pro-oxidants and antioxidants. Albumin and vitamin B₁₂ (B₁₂) are vital antioxidant agents in the circulatory system. This study aimed to investigate the antioxidative role of serum potassium, albumin and B₁₂ in FP.

METHODS

Serum levels of potassium, albumin and B₁₂ were retrospectively analyzed in 21 patients with a confirmed diagnosis of FP, 105 bacterial peritonitis (BP) patients and 210 patients receiving peritoneal dialysis without peritonitis.

RESULTS

Serum levels of potassium, albumin and B₁₂ were lower in FP patients than in BP patients. Serum potassium concentration was statistically related to albumin concentration in peritonitis patients. Univariate and multivariate binary logistic regression analysis suggested that serum level of potassium and albumin were independent risk factors of FP when compared with BP. Lower potassium and B₁₂ levels were independently associated with higher rates of technique failure in peritonitis.

CONCLUSION

These findings suggest lower serum potassium, albumin and B₁₂ as potential oxidative stress markers of FP and raise the hypothesis that an increased level of OS could contribute to FP.KEY MESSAGESFP remains a serious complication of peritoneal dialysis (PD), with higher morbidity (1-23.8%) and mortality (2-25%), and oxidative stress plays a role in it.Our study suggested serum potassium, albumin and vitamin B₁₂ as potential oxidative stress markers of fungal peritonitis.

Effects of vitamin B12 on rat ovary with ischemia-reperfusion injury

We investigated the histopathological and biochemical effects of vitamin B12 on ischemia-reperfusion (I-R) injury using a rat ovarian torsion-detorsion model. We used four groups of female Wistar albino rats. Group 1 (sham group): both ovaries were removed. Group 2 (torsion group): ovarian torsion was established. Group 3 (torsion-detorsion group) perfusion was retored after ischemia for 2 h. Group 4 (torsion-detorsion-vitamin B12 group): after 2 h ovarian torsion, perfusion was re-established and 4 mg/kg vitamin B12 was administered for 2 h. Follicular degeneration, vascular congestion, hemorrhage, edema and infiltration were evaluated histologically. Tissue damage was decreased in group 4 compared to groups 2 and 3. Total antioxidant status TAS), total oxidant status (TOS) and malondialdehyde (MDA) level were measured. The values for TOS and MDA for groups 1 and 4 were similar. We found a significant increase in MDA and TOS levels in group 3 compared to group 2. MDA and TAS levels decreased and TOS levels were increased in group 4 compared to groups 2 and 3. MDA, TAS and TOS values were increased in groups 2 and 3 compared to group 1. We found that vitamin B12 reduced I-R damage in the rat ovary.

The effect of vitamin B12 supplement on post-thaw motility, viability and DNA damage of human sperm

Sperm cryopreservation may lead to adverse effects on sperm structure and function. Cyanocobalamin (vitamin B12) has antioxidant potential and can protect DNA from free radical-induced damages. Recent studies have shown that vitamin B12 preserves glutathione that leads to modulate oxidative stress responses. Also, vitamin B12 might act directly as a scavenger of ROS. The aim of this study was to investigate the effects of vitamin B12 supplementation on human sperm parameters during the cryopreservation process. Thirty semen samples were obtained from normozoospermic men. Using cryopreservation medium supplemented with different concentrations of vitamin B12 (0, 0.5, 1, 2, 2.5 mg/ml), the semen samples were cryopreserved. After thawing, all samples were evaluated for motility and viability. Based on results, 2 mg/ml was considered as the optimal concentration of vitamin B12 for evaluating sperm DNA fragmentation. The results showed that 1 and 2 mg/ml vitamin B12 significantly increased post-thawing motility and viability compared with the 0 mg/ml vitamin B12 (p < .05). Also, by supplementing with 2 mg/ml vitamin B12, DNA fragmentation decreased when compared to the control. The present study showed that cryopreservation medium supplemented with vitamin B12 at 2 mg/ml could improve sperm quality after freeze-thaw process.

Vitamin B12 in Relation to Oxidative Stress: A Systematic Review

The triage theory posits that modest micronutrient deficiencies may induce reallocation of nutrients to processes necessary for immediate survival at the expense of long-term health. Neglected processes could in time contribute to the onset of age-related diseases, in which oxidative stress is believed to be a major factor. Vitamin B12 (B12) appears to possess antioxidant properties. This review aims to summarise the potential antioxidant mechanisms of B12 and investigate B12 status in relation to oxidative stress markers. A systematic query-based search of PubMed was performed to identify eligible publications. The potential antioxidant properties of B12 include: (1) direct scavenging of reactive oxygen species (ROS), particularly superoxide; (2) indirect stimulation of ROS scavenging by preservation of glutathione; (3) modulation of cytokine and growth factor production to offer protection from immune response-induced oxidative stress; (4) reduction of homocysteine-induced oxidative stress; and (5) reduction of oxidative stress caused by advanced glycation end products. Some evidence appears to suggest that lower B12 status is related to increased pro-oxidant and decreased antioxidant status, both overall and for subclinically deficient individuals compared to those with normal B12 status. However, there is a lack of randomised controlled trials and prospective studies focusing specifically on the relation between B12 and oxidative stress in humans, resulting in a low strength of evidence. Further work is warranted.

A mechanistic model for thiol redox dynamics in the organogenesis stage rat conceptus

Precise control of the glutathione/glutathione disulfide (GSH/GSSG) redox balance is vital for the developing embryo, but regulatory mechanisms are poorly understood. We developed a novel, mechanistic mass-balance model for GSH metabolism in the organogenesis stage (gestational day 10.0-11.13) rat conceptus predicting the dynamics of 8 unique metabolites in 3 conceptal compartments: the visceral yolk sac (VYS), the extra-embryonic fluid (EEF) and the embryo proper (EMB). Our results show that thiol concentrations in all compartments are well predicted by the model. Protein synthesis is predicted to be a major efflux pathway for all amino acid precursors of GSH synthesis and an essential model element. Our model provides quantitative insights in the transport fluxes and enzymatic fluxes needed to maintain thiol redox balances under normal physiological conditions. This is crucial to further elucidate the mechanisms through which chemical exposure can perturb redox homeostasis, causing oxidative stress, and potentially birth defects.