Prevalence of micronutrient deficiencies across diverse environments in rural Madagascar.

It is estimated that billions of people around the world are affected by micronutrient deficiencies. Madagascar is considered to be particularly nutritionally vulnerable, with nearly half of the population stunted, and parts of the country facing emergency, near famine-like conditions (IPC4). Although Madagascar is generally considered among the most undernourished of countries, empirical data in the form of biological samples to validate these claims are extremely limited. Our research drew data from three studies conducted between 2013-2020 and provided comprehensive biomarker profile information for 4,710 individuals from 30 communities in five different ecological regions during at least one time-point. Estimated prevalences of nutrient deficiencies and inflammation across various regions of rural Madagascar were of concern for both sexes and across all ages, with 66.5% of the population estimated to be deficient in zinc, 15.6% depleted in vitamin B12 (3.6% deficient), 11.6% deficient in retinol, and lower levels of iron deficiency (as indicated by 11.7% deficient in ferritin and 2.3% deficient assessed by soluble transferrin receptors). Beyond nutrient status biomarkers, nearly one quarter of the population (24.0%) exhibited chronic inflammation based on high values of α-1-acid glycoprotein, and 12.3% exhibited acute inflammation based on high values of C-reactive protein. There is an 8-fold difference between the lowest and highest regional observed prevalence of vitamin B12 deficiency, a 10-fold difference in vitamin A deficiency (based on retinol), and a 2-fold difference in acute inflammation (CRP) and deficiencies of zinc and iron (based on ferritin), highlighting strong geographical variations in micronutrient deficiencies across Madagascar.

Vision Loss as a Presenting Symptom of Vitamin B12 Deficiency.

Nutritional optic neuropathy is a rare and often overlooked factor leading to bilateral, symmetrical, and gradual visual impairment. This condition falls within the category of metabolic neuropathies. We documented a case involving bilateral nutritional optic neuropathy attributed to pancytopenia associated with vitamin B12 deficiency. A healthy 65-year-old Indian woman reported a bilateral, progressive, painless decline in vision over the past six months. She had a history of reduced oral intake for the preceding year and denied experiencing any gastrointestinal or constitutional symptoms. Bilateral visual acuity was 1/60. Examination revealed pale optic discs with attenuated vessels in both eyes and a cup-disc ratio of 0.3. The blood analysis showed low indices and a deficiency in serum vitamin B12. Despite undergoing treatment, her vision remained impaired due to the chronic nature of the condition. This case highlights the importance of identifying visual symptoms in an elderly woman experiencing malnutrition caused by inadequate dietary habits, which leads to bilateral nutritional optic neuropathy.

The independent and joint associations of vitamin B12 and methylmalonic acid on the risk of mortality in individuals with metabolic dysfunction-associated steatotic liver disease.

PURPOSE: To investigate the independent and joint associations of vitamin B12 and methylmalonic acid (MMA) with all-cause, cardiovascular disease (CVD), and cancer mortality in patients with metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: We included 6797 individuals with MASLD from the U.S. National Health and Nutrition Examination Survey. Serum MMA was measured using gas/liquid chromatography-mass spectrometry. Serum vitamin B12 was measured using commercial kits. The separate and joint associations of dietary intake and serum vitamin B12 (cutoff: 400 pg/mL) and MMA (cutoff: 250 nmol/L) levels with mortality were assessed by Cox proportional hazards regression. RESULTS: During a median follow-up of 9.3 years, 1604 deaths were documented, including 438 from CVD and 365 from cancer. In MASLD patients, dietary intake and serum vitamin B12 did not associate with mortality, while MMA was associated with a 1.35-fold increased risk of all-cause mortality (P-trend < 0.001). The adjusted hazard ratios for the joint association of vitamin B12 and MMA with all-cause and CVD mortality were 1 in the B12lowMMAlow group (reference), 1.02 (0.87-1.20) and 1.15 (0.90-1.47) in the B12highMMAlow group, 1.55 (1.29-1.86) and 1.84 (1.28-2.65) in the B12lowMMAhigh group, and 1.82 (1.49-2.21) and 2.28 (1.40-3.71) in the B12highMMAhigh group, respectively. The joint association was modified by serum folate (P-interaction = 0.001). CONCLUSIONS: In MASLD patients, MMA rather than dietary and serum vitamin B12 was positively associated with all-cause mortality. The joint effect of high levels of MMA and vitamin B12 showed the strongest associations with all-cause and CVD mortality, with a significant interaction with serum folate.

Vitamin D and vitamin B12 profiles in children with primary nocturnal enuresis, an analytical cross-sectional study.

PURPOSE: To outline the prevalence of vitamin D and vitamin B12 deficiencies in enuretic children. METHODS: An analytical descriptive study was conducted on enuretic children who were followed up at the outpatient clinic for nocturnal enuresis at the Children's Hospital, Cairo University. Sociodemographic and clinical data were recorded. The levels of vitamin D and vitamin B12 were assessed and correlated with the severity of enuresis. RESULTS: Two hundred and eighty-eight children were enrolled. Insufficiency of Vitamin D predominated (n = 139; 48.3%). Vitamin D deficiency was present in 31.3%, n = 90 and it was normal in 20.5%, n = 59). Vitamin B12 deficiency was observed in 25% of the studied children, n = 72). The one-sample Wilcoxon signed-rank test was significant for both vitamins (P value =0.001). Vitamin D showed a stronger inverse correlation with the number of enuresis episodes per day than vitamin B12 (-0.680 vs. -0.219 respectively). A cut-off of 13.7 ng/ml for vitamin D was detected, below which the child was predicted to have failed dry nights. Using multivariate logistic regression, higher vitamin D levels and behavioural treatment coexistence were significant protective factors for the absence of dry nights. CONCLUSION: Low levels of vitamin D and B12 were detected in children with primary nocturnal enuresis, which could be considered a burden on the clinical severity of enuresis.

What is already known on this topic?Children with Primary Nocturnal Enuresis may have vitamin D and vitamin B₁₂ abnormalities as deficienciesWhat does this study add?Vitamin D insufficiency may be the most prevalent vitamin D abnormality in children with primary nocturnal enuresis. Vitamin D insufficiency may be more common in children with severe enuresis than vitamin B₁₂ deficiency.How might this study affect research, practice, or policy?This study may invite further research to examine the possible use of vitamin D and vitamin B12 as potential adjuvant therapies for children with Primary Nocturnal Enuresis.

Impact of vitamin B12 supplement intake cessation on vitamin B12 status in a healthy vegan: A close interval monitoring case study.

BACKGROUND: Healthy plant-based diets, such as the lacto-ovo-vegetarian and the vegan diet, offer numerous benefits to human health. Poorly designed plant-based diets, however, bear the risk for vitamin- and micronutrient deficiencies. Vitamin B12 (B12, cobalamin) is a nutrient of particular concern in both diets, and should be readily supplemented on a continuous basis to ensure adequate B12 levels and to prevent deficiencies. CASE REPORT: This case reports describes the history of a healthy man in his mid-30s who adopted a vegan diet approximately 10 y ago. Well informed about the risks of vitamin B12 deficiency on a plant-based diet, he regularly supplemented methylcobalamin for years (single oral dose: 500 µg, 3-4 times a week) in order to maintain an adequate vitamin B12 status. In late 2023, however, he decided to cease B12 supplementation for undisclosed reasons. Subsequent to this decision, we closely monitored his B12 status and longitudinally measured serum B12, homocysteine, and holotranscobalamin (holo-TC). Total serum folate was also determined as it is a modifier of homocysteine concentration. A gradual decrease in holo-TC and vitamin B12 levels was observed after 4 weeks and supplements had to be re-introduced after 16 weeks. Homocysteine increased concomitantly up to 18.2 µmol/L after 20 weeks. CONCLUSIONS: While a short-term B12 supplement intake cessation might be well tolerated by vegans with an adequate B12 status, an interruption of more than 8 weeks could signify B12 loss approaching suboptimal status. This case report reiterates the need for continuous B12 supplementation in persons following an unfortified plant-based diet.

Soil microbial community response to corrinoids is shaped by a natural reservoir of vitamin B12.

Soil microbial communities perform critical ecosystem services through the collective metabolic activities of numerous individual organisms. Most microbes use corrinoids, a structurally diverse family of cofactors related to vitamin B12. Corrinoid structure influences the growth of individual microbes, yet how these growth responses scale to the community level remains unknown. Analysis of metagenome-assembled genomes suggests corrinoids are supplied to the community by members of the archaeal and bacterial phyla Thermoproteota, Actinobacteria, and Proteobacteria. Corrinoids were found largely adhered to the soil matrix in a grassland soil, at levels exceeding those required by cultured bacteria. Enrichment cultures and soil microcosms seeded with different corrinoids showed distinct shifts in bacterial community composition, supporting the hypothesis that corrinoid structure can shape communities. Environmental context influenced both community and taxon-specific responses to specific corrinoids. These results implicate corrinoids as key determinants of soil microbiome structure and suggest that environmental micronutrient reservoirs promote community stability.

Anaemia in India and Its Prevalence and Multifactorial Aetiology: A Narrative Review.

The prevalence of anaemia in India remains high in children, especially those in rural areas, and in women of childbearing age, and its impairment of neurological development can have serious lifelong effects. It is concerning that the most recent official data (2019-21) indicate an increased prevalence compared with 2015-16. There is also considerable variability in childhood anaemia between Indian states with socioeconomic factors, such as wealth and education contributing to the risk of anaemia among adolescent women and their children. Dietary iron deficiency is often regarded as the main contributor to anaemia but increasing evidence accumulated from the authors' ongoing literature database coupled with recent literature research suggests that it has a multifactorial aetiology, some of which is not related to nutrition. This narrative review focused on these multifactorial issues, notably the contribution of vitamin B12/folate deficiency, which also has a high prevalence in India. It was also noted that the dietary intake of bioavailable iron remains an important contributor for reducing anaemia, and the role of millets as an improved iron source compared to traditional staple cereals is briefly discussed. The overall conclusion is that anaemia has a multifactorial aetiology requiring multifactorial assessment that must include assessment of vitamin B12 status.

Distribution and correlates of plasma folate, vitamin B12, and homocysteine in a sample of low-income minority children aged 6 months to 9 years in the U.S.

Background: Precision nutrition emphasizes tailoring dietary requirements across populations and life stages. Optimal folate and vitamin B12 levels are important for normal growth and development, but data are lacking for low-income minority U.S. children during early life periods. This study aimed to describe folate, vitamin B12, homocysteine (Hcy) levels, and influencing factors to address the gaps. Methods: Blood samples from children aged 6 months to 9 years and mothers 48-72 hours postpartum in the Boston Birth Cohort (BBC) were tested for folate, vitamin B12, and Hcy. Maternal and child characteristics, sociodemographic factors, and feeding status were obtained from a standard maternal questionnaire interview at the enrollment and follow-up, and medical records. The distribution of children's folate, vitamin B12, and Hcy were described and factors influencing these biomarkers were analyzed. Results: A wide distribution of folate, vitamin B12, and Hcy levels was observed in this sample, with longitudinal trends consistent with National Health and Nutrition Examination Survey (NHANES) data. Multivariate analysis showed that very preterm birth correlated with higher folate levels (adjusted ß 4.236; 95% CI: 1.218, 7.253; p=0.006). Children aged 1-2 years and 3-8 years had lower folate levels compared to those <1 year (adjusted ß -10.191 and -7.499 respectively; p<0.001). Vitamin B12 levels were higher in Black children (adjusted fold change 1.139; 95% CI: 1.052, 1.233; p=0.001) and those children whose mothers' B12 levels were at the highest quartile (Q4) (adjusted fold change 1.229; 95% CI: 1.094, 1.380; p=0.001). Delayed solid food introduction (> 6 months) correlated with lower children's B12 levels (adjusted fold change 0.888; 95% CI: 0.809, 0.975; p=0.013). Hcy levels were lower in Black children (adjusted fold change 0.962; 95% CI: 0.932, 0.993; p=0.018), higher in children with maternal Hcy levels in Q4 (adjusted fold change 1.081; 95% CI: 1.03, 1.135; p=0.002) and in children aged 3-8 years (adjusted fold change 1.084; 95% CI: 1.040, 1.131; p< 0.001). Conclusions: This study revealed wide variations in plasma folate, vitamin B12, and Hcy levels among low-income minority U.S. children and identified race, maternal levels, child's age, prematurity, and timing of solid food introduction as significant correlates.

Prevalence of vitamin B 12 deficiency and associated factors among primary school children: North East Ethiopia: multicenter cross-sectional study.

BACKGROUND: The prevalence of Vitamin B12 deficiency is common and is more frequent in low- and middle-income countries with a poor or inadequate diet of animal foods. In Ethiopia, researches related to the status of micronutrients in children are limited. Therefore, this study aimed to assess the prevalence of vitamin B12 deficiency and associated factors among primary school children. METHODS: A cross-sectional study design was conducted from January 10-February 30/2023. A total of 514 students were selected using a systematic random sampling technique. Face-to-face interviews using a structured questionnaire, document review, anthropometric measurement, and laboratory studies were implemented to collect data. Data was analyzed by STATA version 14 and summarized by using frequency tables and graphs. Logistic regression analysis was done to identify factors associated with vitamin B12 Deficiency. RESULTS: About 34% of the students were found to have vitamin B12 deficiency. Not Consuming animal products (AOR = 1.83, 95% CI:1.20-2.79) and low body mass index (AOR = 1.62, 95% CI:1.05-2.47) were associated with vitamin B12 deficiency. CONCLUSIONS: The study revealed a notable high deficiency of vitamin B12 in primary school students. Consumption of animal products and BMI were identified as statically significant associated factors with serum concentration of vitamin B12.

Assessment of Helicobacter pylori cytotoxin-associated Gene A (Cag A) protein and its association with ferritin and vitamin B12 deficiencies among adult healthy asymptomatic residents in Sharjah, United Arab Emirates.

The United Arab Emirates (UAE) serves as an effective epidemiological site for assessing Helicobacter pylori (H. pylori) infection due to its diverse population. However, comprehensive studies on the prevalence of H. pylori in the UAE are notably scarce. In depth prevalence studies are needed as a preventive measure against gastric cancer and other emerging extra gastric diseases associated with H. pylori infection. Aim: This study aimed to assess H. pylori infection and its virulent oncoprotein, the Cytotoxin-Associated Gene (Cag A) and its association with ferritin and vitamin B12 deficiencies. Methods: The study was conducted on 1094 healthy asymptomatic volunteers residents in the Sharjah Emirate, UAE. Enzyme-linked immunosorbent assay (ELISA) was performed to assess H. pylori infection using H. pylori antibodies (IgG), and detection of CagA protein using Cag A antibody (IgG) in the human serum. Ferritin and vitamin B12 serum levels were assessed and correlated to H. pylori infection. Results: This study focuses mainly on the assessment of H. pylori and its virulent factor CagA, in relation to vitamin B12 and ferritin deficiencies. Remarkably, 49.6 % of the participants were detected positive for H. pylori, with over half of these cases involving CagA positive strains. Notably, among Emirati participants, 76.11 % of those with H. pylori infection were CagA positive. Statistical analysis revealed a significant correlation between H. pylori, CagA level, and ferritin/vitamin B12 deficiencies. Conclusion: These findings emphasize the importance of timely detection and eradication of H. pylori not only as a preventive strategy against gastric cancer but also as an effective strategy to rescue the adverse effects from ferritin and vitamin B12 deficiencies, thereby improving the overall health outcomes of individuals affected by H. pylori infection.

Benefits of Combining Antiepileptic Drugs with Vitamin B12 on Redox Balance: Penicillin-Induced Experimental Epilepsy Model.

Purpose: A combination of antiepileptic drugs and antioxidants may be an effective treatment by restoring the disrupted redox balance and reducing oxidative stress exposure to neurons. This study aims to evaluate the effects of valproate and vitamin B12 on oxidative stress in an experimental epilepsy model induced by penicillin when administered alone or in combination. Patients and Methods: 35 male Wistar rats were used in this study. The rats were divided into five groups, which were saline group, 1 mg/kg, 2 mg/kg Vit B12 groups and Sodium valproate group Sodium valproate + Vit B12 group. The epileptic activity was induced by 500 IU of penicillin injection. Sodium valproate and Vitamin B12 were administered 30 min after penicillin administration. Electrocorticogram recordings were taken for 2 hours post-treatment and serum parameters were assessed for oxidative stress markers using spectrophotometric method. Results: There is statistically significant difference between the groups in total antioxidant status, total oxidant status, and oxidative stress index value (p=0.013; p˂0.001; p˂0.001, respectively). The valproate+vitamin B12 group showed elevated total thiol and native thiol levels, along with reduced disulphide levels, resulting in the lowest OSI value. Conclusion: These findings suggest the combined treatment effectively reduces oxidative stress. This study provides valuable insights into the antioxidant properties of valproate and vitamin B12, positioning them as potential agents for managing epilepsy. Understanding the efficacy and reliability of antioxidant strategies in epilepsy management could contribute significantly to advancements in epilepsy therapeutics.

Overuse Ordering Serum Vitamin B12: A Call for Appropriate Ordering Guidelines Based on a Single Institutional Experience.

OBJECTIVE: Vitamin B12 is an essential nutrient for numerous functions in the human body. As such, many clinical scenarios justify assaying serum B12; however, there are no evidence-based guidelines available for determining when to order B12 tests. Here we investigate B12 assay ordering patterns to identify methods of enhancing efficiency and minimizing inappropriate requests. METHODS: All serum B12 requests within the year spanning July 2018 to June 2019 were reviewed using the hospital's health information system. These amounted to 3,400 requests, of which data from the first 1,000 were evaluated. Patient demographics, hematological data, serum folate, and ferritin were extracted from the electronic requests. Physician identity and request reason were retrieved where available. RESULTS: Of the 877 B12 requests for which patient age was available, the majority (80.3%) were for young and middle-aged patients. Interestingly, serum B12 was low in only a quarter of the 1,000 reviewed requests; the remaining three quarters had normal levels. Folate, which can be ordered with vitamin B12, was tested in 82 cases, of which only two (2.4%) had folate deficiency. CONCLUSION: This study highlights a high occurrence of improper ordering of vitamin B12 assays, indicating a need for revised guidelines to promote optimal test ordering.

Is serum homocysteine level a biomarker of suicide attempts: A preliminary study.

Suicide is a global public health concern, and understanding its multifaceted determinants is crucial for effective prevention. This study was designed to find an answer to the question of whether serum homocysteine level can be a biomarker of suicide attempts. This preliminary study involving 90 participants (45 suicide attempt cases and 45 controls) was conducted at Elazig Fethi Sekin City Hospital. Biochemical analyses were performed to assess serum homocysteine, vitamin B12, and folic acid levels. Statistical analyses, including t-tests, Mann-Whitney U tests, and ROC analysis, were employed to explore differences between groups and assess the diagnostic potential of homocysteine. Elevated homocysteine levels were found in individuals who attempted suicide compared to the control group (p= <0.001). Additionally, lower levels of vitamin B12 (p=<0.001) and folic acid (p=<0.001) were observed in the suicide attempt group. ROC analysis indicated a significant diagnostic potential for homocysteine in predicting suicide attempts (AUC = 0.845, sensitivity = 91%, specificity = 71%). This study establishes a significant association between high homocysteine levels and suicide attempts, accompanied by lower vitamin B12 and folic acid levels. The findings suggest a potential link between disturbances in homocysteine metabolism and suicidal tendencies, urging further research to establish causation and explore therapeutic implications. Consideration of the study's limitations and directions for future research are warranted.

Infantile tremor syndrome with global developmental delay and microcephaly in a 16-month-old male: a case report.

Introduction and importance: Infantile tremor syndrome (ITS) affects children aged 6-18 months, and is characterized by tremors, pallor, developmental regression, skin pigmentation changes, and sparse hypopigmented hair. This case report highlights an ITS presentation in a 16-month-old exclusively breastfed male, emphasizing the significance of complementary feeding. Case presentation: The patient presented with abnormal body movements, loss of developmental milestones, hyperpigmented skin changes, hypopigmented scalp hairs, pallor, and microcephaly. Born to a vegetarian mother with inadequate prenatal care, the child's exclusive breastfeeding till 16 months of age without complementary feeding led to severe developmental delay and moderate malnutrition. Diagnostic workup revealed vitamin B12 deficiency, anaemia, and neurologic abnormalities. Clinical discussion: ITS is associated with various manifestations, including pallor, hyperpigmentation, and tremors, commonly linked to vitamin B12 deficiency. In this case, developmental delays and malnutrition underscored the importance of early recognition. Despite neurological improvement with vitamin B12 supplementation, ITS's long-term impact on cognitive functions necessitates vigilance and appropriate nutritional interventions. Conclusion: Early recognition of ITS is vital for the prevention of long-term neurodevelopmental sequelae. Injectable vitamin B12 supplementation and nutritional interventions have demonstrated significant developmental gains. Increased awareness among mothers about nutritional intake during pregnancy and lactation is crucial, especially among vegetarians.

Looking for ALPS: The value of a combined assessment of biochemical markers.

BACKGROUND: Autoimmune lymphoproliferative syndrome (ALPS) is a rare primary immune disorder caused by defect of the extrinsic apoptotic pathway. The current diagnostic criteria combine clinical features and typical biomarkers but have not been the object of clear international consensus. METHODS: We conducted a retrospective study on pediatric patients who were investigated for autoimmune cytopenia and/or lymphoproliferation at the CHU Sainte-Justine Hospital over 10 years. Patients were screened using the combination of TCRαß+ CD4- CD8- "double negative" (DN) T cells and soluble plasmatic FAS ligand (sFASL). RESULTS: Among the 398 tested patients, the median sFASL and DN T cells were 200 ng/mL and 1.8% of TCRαß+ T cells, respectively. sFASL was highly correlated with vitamin B12 levels. We identified five patients diagnosed with ALPS for whose sFASL and vitamin B12 levels were the more discriminating biomarkers. While ALPS diagnostic criteria had high sensibility, their predictive value remained low. CONCLUSION: sFASL level can efficiently discriminate patients with ALPS when using the appropriate thresholds. Our study highlights the need for an international consensus to redefine the place and threshold of biological biomarkers for ALPS diagnosis.

Role of vitamin B12 and folic acid in treatment of Alzheimer's disease: a meta-analysis of randomized control trials.

Vitamin B12 and folic acid could reduce blood homocysteine levels, which was thought to slow down the progression of Alzheimer's disease (AD), but previous studies regarding the effect of vitamin B12 and folic acid in treatment of AD have not reached conclusive results. We searched PubMed and Embase until January 12, 2023. Only randomized control trials involving participants clearly diagnosed with AD and who received vitamin B12 and folic acid were enrolled. Five studies that met the criteria were selected for inclusion in the meta-analysis. Changes in cognitive function were measured based on either the Mini-Mental State Examination (MMSE) or the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog). Changes in daily life function and the level of blood homocysteine were also investigated. After a 6-month treatment, administration of vitamin B12 and folic acid improved the MMSE scores more than placebo did (SMD = 0.21, 95% CI = 0.01 to 0.32, p = 0.04) but did not significantly affect ADAS-Cog scores (SMD = 0.06, 95% CI = -0.22 to 0.33, p = 0.68) or measures of daily life function. Blood homocysteine levels were significantly decreased after vitamin B12 and folic acid treatment. Participants with AD who received 6 months of vitamin B12 and folic acid supplementation had better MMSE scores but had no difference in ADAS-Cog scores. Daily life function did not improve after treatment.

Exploring Vitamin B12 Supplementation in the Vegan Population: A Scoping Review of the Evidence.

With a significant portion of the population adopting veganism and conflicting views among nutrition professionals regarding the necessity of vitamin B12 supplementation, this review aims to explore existing studies evaluating interventions through food supplementation. It focuses on the impact of vitamin B12 deficiency across different demographics. The present study seeks to understand how research has addressed the relationship between the rise in veganism and vitamin B12 deficiency over the past decade. A scoping review was conducted following the PRISMA flow diagram. Studies from 2010 to 2023 were identified using Boolean operators and key terms in electronic databases such as PubMed/MEDLINE, Web of Science, and EBSCO (Library, Information Science & Technology Abstracts, and Academic Search Complete). Out of 217 articles identified, 70 studies were included. The topical analysis categorized the studies into three groups: those associating vitamin B12 deficiency with diseases (n = 14), those analyzing the dietary habits of vegetarian individuals (vegan or not) without a specific focus on vitamin B12 (n = 49), and those addressing food guides and nutrition institution positions (n = 7). The authors concluded that vitamin B12 deficiency is prevalent among vegans due to limited consumption of animal products. For vegetarians, supplementation is an efficient means of treating and preventing deficiency; a daily dose of 50 to 100 micrograms is advised. There are still significant gaps in the research, nevertheless, such as the absence of randomized controlled trials evaluating various forms or dosages of vitamin B12 among vegetarians and the requirement for more information and awareness of the vitamin's significance in vegan diets.

Vitamin B12 Supplementation in Psychiatric Practice.

PURPOSE OF REVIEW: Vitamin B12 (B12, cobalamin) deficiency has been associated with neuropsychiatric symptoms, suggesting a role for B12 supplementation both as a treatment for psychiatric symptoms due to B12 deficiency and as an augmentation strategy for pharmacological treatments of psychiatric disorders. This critical review discusses the major causes of B12 deficiency, the range of psychiatric and non-psychiatric manifestations of B12 deficiency, the indications for testing B12 levels, and the evidence for B12 supplementation for major psychiatric disorders. RECENT FINDINGS: We find that high-quality evidence shows no benefit to routine B12 supplementation for mild depressive symptoms or to prevent depression. There is very limited evidence on the role of B12 supplementation to augment antidepressants. No high-quality evidence to date suggests a role for routine B12 supplementation in any other major psychiatric disorder. No formal guidelines indicate when clinicians should test B12 levels for common psychiatric symptoms, in the absence of major risk factors for deficiency or cardinal symptoms of deficiency. No robust evidence currently supports routine B12 supplementation for major psychiatric disorders. However, psychiatrists should be aware of the important risk factors for B12 deficiency and should be able to identify symptoms of B12 deficiency, which requires prompt testing, medical workup, and treatment. Testing for B12 deficiency should be considered for atypical or severe psychiatric presentations.

Vitamin B12 uptake across the mycobacterial outer membrane is influenced by membrane permeability in Mycobacterium marinum.

Vitamin B12 (B12) serves as a critical cofactor within mycobacterial metabolism. While some pathogenic strains can synthesize B12 de novo, others rely on host-acquired B12. In this investigation, we studied the transport of vitamin B12 in Mycobacterium marinum using B12-auxotrophic and B12-sensitive strains by deleting metH or metE, respectively. These two enzymes rely on B12 in different ways to function as methionine synthases. We used these strains to select mutants affecting B12 scavenging and confirmed their phenotypes during growth experiments in vitro. Our analysis of B12 uptake mechanisms revealed that membrane lipids and cell wall integrity play an essential role in cell envelope transport. Furthermore, we identified a potential transcription regulator that responds to B12. Our study demonstrates that M. marinum can take up exogenous B12 and that altering mycobacterial membrane integrity affects B12 uptake. Finally, during zebrafish infection using B12-auxotrophic and B12-sensitive strains, we found that B12 is available for virulent mycobacteria in vivo.IMPORTANCEOur study investigates how mycobacteria acquire essential vitamin B12. These microbes, including those causing tuberculosis, face challenges in nutrient uptake due to their strong outer layer. We focused on Mycobacterium marinum, similar to TB bacteria, to uncover its vitamin B12 absorption. We used modified strains unable to produce their own B12 and discovered that M. marinum can indeed absorb it from the environment, even during infections. Changes in the outer layer composition affect this process, and genes related to membrane integrity play key roles. These findings illuminate the interaction between mycobacteria and their environment, offering insights into combatting diseases like tuberculosis through innovative strategies. Our concise research underscores the pivotal role of vitamin B12 in microbial survival and its potential applications in disease control.