Megaloblastic anaemia: Folic acid and vitamin B12 metabolism

Identifying patterns to uncover the importance of biological pathways on known drug repurposing scenarios

BACKGROUND

Drug repurposing plays a significant role in providing effective treatments for certain diseases faster and more cost-effectively. Successful repurposing cases are mostly supported by a classical paradigm that stems from de novo drug development. This paradigm is based on the "one-drug-one-target-one-disease" idea. It consists of designing drugs specifically for a single disease and its drug's gene target. In this article, we investigated the use of biological pathways as potential elements to achieve effective drug repurposing.

METHODS

Considering a total of 4214 successful cases of drug repurposing, we identified cases in which biological pathways serve as the underlying basis for successful repurposing, referred to as DREBIOP. Once the repurposing cases based on pathways were identified, we studied their inherent patterns by considering the different biological elements associated with this dataset, as well as the pathways involved in these cases. Furthermore, we obtained gene-disease association values to demonstrate the diminished significance of the drug's gene target in these repurposing cases. To achieve this, we compared the values obtained for the DREBIOP set with the overall association values found in DISNET, as well as with the drug's target gene (DREGE) based repurposing cases using the Mann-Whitney U Test.

RESULTS

A collection of drug repurposing cases, known as DREBIOP, was identified as a result. DREBIOP cases exhibit distinct characteristics compared with DREGE cases. Notably, DREBIOP cases are associated with a higher number of biological pathways, with Vitamin D Metabolism and ACE inhibitors being the most prominent pathways. Additionally, it was observed that the association values of GDAs in DREBIOP cases were significantly lower than those in DREGE cases (p-value < 0.05).

CONCLUSIONS

Biological pathways assume a pivotal role in drug repurposing cases. This investigation successfully revealed patterns that distinguish drug repurposing instances associated with biological pathways. These identified patterns can be applied to any known repurposing case, enabling the detection of pathway-based repurposing scenarios or the classical paradigm.

Vitamin B12 sources in non-animal foods: a systematic review

Interest in plant-based diets and vegetarianism is increasing worldwide, however, a concern for total vegetarians is vitamin B12 (B12) deficiency. We conducted a systematic review to investigate non-animal food sources of B12. Databases were PubMed, LILACS, Cochrane, Embase and Google Scholar, up to September 9, 2020. Quality of the eligible studies were assessed. We identified 25 studies which assessed B12 content in seaweeds, mushrooms, plants and fermented foods. Initial studies were microbiological bioassay, ELISA and HPLC. In the last decade, more sensitive method for real B12 determination was used, the liquid chromatography-electrospray ionization tandem mass spectrometry chromatograms. Real B12 content varied from mean (SD) mcg/portion size of seaweed hijiki 3 × 10-3/7 g to nori 1.03 - 2.68/sheet; mushroom white button cap 2 × 10-3(7 × 10-4)/20 g dry weight (dw) to shiitake 0.79(0.67)-1.12 (0.78)/20 g dw; and fermented foods from soy yogurt 20/cup. It is possible that daily recommendations for B12 can be met by a varied diet containing non-animal B12 food sources. Future research should consider different methods of storage, preparation, fermented foods and standardization of the production of certain foods.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2022.2053057.

Dietary Intake and Status of Vitamin B12 in Slovenian Population

Vitamin B12 deficiency poses a health concern, especially in vulnerable populations. Dietary vitamin B12 intake was obtained by two 24 h dietary recalls and food propensity questionnaires in a representative Slovenian cross-sectional food consumption survey, SI.Menu (n = 1248 subjects; 10-74 years). For a subgroup of 280 participants, data on serum vitamin B12 were available through the Nutrihealth study. The estimated usual population-weighted mean daily vitamin B12 intakes were 6.2 µg (adults), 5.4 µg (adolescents), and 5.0 µg (elderly). Lower intakes were observed in females. Inadequate daily vitamin B12 intake (<4 µg) was detected in 37.3% of adolescents, 31.7% of adults, and 58.3% elderlies. The significant predictors for inadequate daily vitamin B12 intake were physical activity score in all age groups, sex in adolescents and adults, financial status and smoking in elderly, and employment in adults. Meat (products), followed by milk (products), made the highest vitamin B12 contribution in all age groups. In adolescents, another important vitamin B12 contributor was cereals. The mean population-weighted serum vitamin B12 levels were 322.1 pmol/L (adults) and 287.3 pmol/L (elderly). Low serum vitamin B12 concentration (<148 nmol/L) and high serum homocysteine (>15 µmol/L) were used as criteria for vitamin B12 deficiency. The highest deficiency prevalence was found in elderlies (7.0%), particularly in males (7.9%). Factors associated with high serum homocysteine were also investigated. In conclusion, although vitamin B12 status was generally not critical, additional attention should be focused particularly to the elderly.

Prevalence and aetiologies of anaemia among first trimester pregnant women in Sri Lanka; the need for revisiting the current control strategies

BACKGROUND

The Sustainable development goals, which focus strongly on equity, aim to end all forms of malnutrition by 2030. However, a significant cause of intergenerational transfer of malnutrition, anaemia in pregnancy, is still a challenge. It is especially so in the low- and middle-income settings where possible context-specific aetiologies leading to anaemia have been poorly explored. This study explores the prevalence of etiological factors significantly contributing to anaemia in pregnancy in Sri Lanka, a lower-middle-income country with a high prevalence of malnutrition albeit robust public health infrastructure.

METHODS

All first-trimester pregnant women registered in the public maternal care programme in the Anuradhapura district from July to September 2019 were invited to participate in Rajarata Pregnancy Cohort (RaPCo). After a full blood count analysis, high-performance liquid chromatography, peripheral blood film examination, serum B12 and folate levels were performed in anaemic participants, guided by an algorithm based on the red cell indices in the full blood count. In addition, serum ferritin was tested in a random subsample of 213 participants. Anaemic women in this subsample underwent B12 and folate testing.

RESULTS

Among 3127 participants, 14.4% (95%CI 13.2-15.7, n = 451) were anaemic. Haemoglobin ranged between 7.4 to 19.6 g/dl. 331(10.6%) had mild anaemia. Haemoglobin ≥13 g/dl was observed in 39(12.7%). Microcytic, normochromic-normocytic, hypochromic-normocytic and macrocytic anaemia was observed in 243(54%), 114(25.3%), 80(17.8%) and two (0.4%) of full blood counts in anaemic women, respectively. Microcytic anaemia with a red cell count ≥5 * 106 /μl demonstrated a 100% positive predictive value for minor haemoglobinopathies. Minor hemoglobinopathies were present in at least 23.3%(n = 105) of anaemic pregnant women. Prevalence of iron deficiency, B12 deficiency and Southeast Asian ovalocytosis among the anaemic was 41.9% (95%CI 26.4-59.2), 23.8% (95%CI 10.6-45.1) and 0.9% (95%CI 0.3-2.3%), respectively. Folate deficiency was not observed.

CONCLUSION

Even though iron deficiency remains the primary cause, minor hemoglobinopathies, B 12 deficiency and other aetiologies substantially contribute to anaemia in pregnancy in this study population. Public health interventions, including screening for minor hemoglobinopathies and multiple micronutrient supplementation in pregnancy, should be considered in the national programme for areas where these problems have been identified.

Impact of daily-supervised administration of a package of iron and folic acid and vitamin B12 on hemoglobin levels among adolescent girls (12-19 years): a cluster randomized control trial

OBJECTIVE

The prevalence of anemia has remained high among Indian adolescent girls over the past decade, despite the ongoing iron and folic acid (IFA) supplementation program. This study was conducted to assess the impact of daily supplementation of a package of IFA with vitamin B₁₂ on hemoglobin levels among adolescent girls.

METHODS

A community-based cluster-randomized trial was conducted in the rural block of Faridabad District, Haryana, India in the year 2017. A total of 760 adolescent girls in the age group of 12-19 years with mild and moderate anemia were selected from government schools. Daily-supervised administration of iron and folic acid was conducted for 90 days: experimental group-IFA (iron (60 mg), folic acid (500) mcg), and cyanocobalamin (1000 mcg), control group-IFA and placebo. Hemoglobin, serum ferritin, and vitamin B₁₂ levels were assessed at baseline and endline.

RESULTS

Two-hundred adolescent girls completed 90 doses of daily supplementation. The mean hemoglobin (experimental group: 1.3 ± 1.0 g/dL, control group: 1.6 ± 1.2 g/dL, P = 0.004) and ferritin levels (experimental group: 18.6 ± 31.5 ng/mL, control group: 18.8 ± 35.0 ng/mL, P = 0.188) increased in both the control and experiment groups. Serum vitamin B₁₂ deficiency significantly reduced to 2.5% in the experimental group and ferritin deficiency alleviated in more than 96% of the girls post intervention.

CONCLUSIONS

Daily supplementation of IFA with/without vitamin B₁₂ for 90 days eliminated iron, vitamin B₁₂ deficiency and reduced the overall proportion of anemia by 53.5%. However, addition of vitamin B₁₂ to IFA supplementation had no impact on improving the hemoglobin levels among adolescent girls. The present study does not recommend provision of vitamin B₁₂ for prevention and treatment of anemia in this population group.

Association between antiseizure medication use and risk of urinary tract infection: A case-control study

AIM

The aim of this study was to analyze the association between antiseizure medication (ASM) and the risk of urinary tract infections (UTI) in patients with epilepsy treated in general practices in Germany.

METHODS

This study includes a total of 2201 patients (mean age: 61.4) whose first documented UTI diagnosis occurred between January 2015 and December 2019 (index date) and who were prescribed at least one ASM in 1198 general practices in Germany within one year prior to the index date. Based on a case-control design, the association between predefined criteria and UTI was investigated by matching (1:1) controls without UTI to cases with UTI by sex, age, and codiagnoses. Logistic regression models were used to analyze the association between ASM use and UTI risk.

RESULTS

In the first regression model, phenytoin (PHT), primidone, carbamazepine (CBZ), and valproate (VPA) were associated with an increased risk of UTI. In the second model, these associations were confirmed with effects per prescription for PHT, primidone, CBZ, and VPA use. Additionally, the effect per prescription was significant for oxcarbazepine (OXC), topiramate, and gabapentin.

CONCLUSION

The study found that PHT, primidone, CBZ, and VPA in particular are associated with an increased risk of infections of the urinary tract. Oxcarbazepine, topiramate, and gabapentin are also associated with increased risk of UTI, albeit to a less significant extent. In general, the immunological and hematological side effects of these molecules may play an important role in the development of UTI under anticonvulsant therapy.

Unexplored nutritive potential of tomato to combat global malnutrition

Tomato, a widely consumed vegetable crop, offers a real potential to combat human nutritional deficiencies. Tomatoes are rich in micronutrients and other bioactive compounds (including vitamins, carotenoids, and minerals) that are known to be essential or beneficial for human health. This review highlights the current state of the art in the molecular understanding of the nutritional aspects, conventional and molecular breeding efforts, and biofortification studies undertaken to improve the nutritional content and quality of tomato. Transcriptomics and metabolomics studies, which offer a deeper understanding of the molecular regulation of the tomato's nutrients, are discussed. The potential uses of the wastes from the tomato processing industry (i.e., the peels and seed extracts) that are particularly rich in oils and proteins are also discussed. Recent advancements with CRISPR/Cas mediated gene-editing technology provide enormous opportunities to enhance the nutritional content of agricultural produces, including tomatoes. In this regard, genome editing efforts with respect to biofortification in the tomato plant are also discussed. The recent technological advancements and knowledge gaps described herein aim to help explore the unexplored nutritional potential of the tomato.

Association of dietary folate and vitamin B-12 intake with genome-wide DNA methylation in blood: a large-scale epigenome-wide association analysis in 5841 individuals

BACKGROUND

Folate and vitamin B-12 are essential micronutrients involved in the donation of methyl groups in cellular metabolism. However, associations between intake of these nutrients and genome-wide DNA methylation levels have not been studied comprehensively in humans.

OBJECTIVE

The aim of this study was to assess whether folate and/or vitamin B-12 intake are asssociated with genome-wide changes in DNA methylation in leukocytes.

METHODS

A large-scale epigenome-wide association study of folate and vitamin B-12 intake was performed on DNA from 5841 participants from 10 cohorts using Illumina 450k arrays. Folate and vitamin B-12 intakes were calculated from food-frequency questionnaires (FFQs). Continuous and categorical (low compared with high intake) linear regression mixed models were applied per cohort, controlling for confounders. A meta-analysis was performed to identify significant differentially methylated positions (DMPs) and regions (DMRs), and a pathway analysis was performed on the DMR annotated genes.

RESULTS

The categorical model resulted in 6 DMPs, which are all negatively associated with folate intake, annotated to FAM64A, WRAP73, FRMD8, CUX1, and LCN8 genes, which have a role in cellular processes including centrosome localization, cell proliferation, and tumorigenesis. Regional analysis showed 74 folate-associated DMRs, of which 73 were negatively associated with folate intake. The most significant folate-associated DMR was a 400-base pair (bp) spanning region annotated to the LGALS3BP gene. In the categorical model, vitamin B-12 intake was associated with 29 DMRs annotated to 48 genes, of which the most significant was a 1100-bp spanning region annotated to the calcium-binding tyrosine phosphorylation-regulated gene (CABYR). Vitamin B-12 intake was not associated with DMPs.

CONCLUSIONS

We identified novel epigenetic loci that are associated with folate and vitamin B-12 intake. Interestingly, we found a negative association between folate and DNA methylation. Replication of these methylation loci is necessary in future studies.

Diagnostic and Treatment Challenges of Paroxysmal Nocturnal Hemoglobinuria in Uganda

Introduction

Paroxysmal nocturnal hemoglobinuria (PNH) is a very rare disorder of the hematopoietic stem cells which is often underdiagnosed. Its incidence is about 5 cases per million inhabitants in a year, and currently, there are only 1610 patients in the International PNH Registry. In this report, we describe a case of PNH in southwestern Uganda.

Case Presentation

A 34-year-old man, subsistence farmer, with a history of multiple prior presentations with anemia, jaundice, and dark-colored urine requiring blood transfusions presented to us again in July 2018 with a week's history of palpitations, dizziness, and dark-colored urine. Investigations done suggested a direct antiglobulin test- (DAT-) negative hemolytic anemia, and subsequently, flow cytometry showed a large clone of PNH. He received many blood transfusions and hematinics on several occasions during the course of his admissions.

Conclusions

Our report showed diagnostic and treatment challenges of PNH in health resource-limited setting.