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Keywords = methylcobalamin

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7 pages, 350 KiB  
Article
Evaluation of a New Sublingual Methylcobalamin Dosage Regimen for Childhood Vitamin B12 Deficiency
by Sultan Aydin, Suheyla Ceren Islamoglu and Ayse Oz
Children 2025, 12(4), 442; https://doi.org/10.3390/children12040442 - 30 Mar 2025
Viewed by 1815
Abstract
Background: Effective and timely treatment of vitamin B12 deficiency in childhood is crucial because it can lead to serious issues, including delayed growth and neuromotor development. Available treatment options include oral, intramuscular, and sublingual administration. Aim: This study investigated the efficacy of a [...] Read more.
Background: Effective and timely treatment of vitamin B12 deficiency in childhood is crucial because it can lead to serious issues, including delayed growth and neuromotor development. Available treatment options include oral, intramuscular, and sublingual administration. Aim: This study investigated the efficacy of a new dosing protocol for sublingual methylcobalamin. Materials and Methods: In total, 312 patients with vitamin B12 deficiency (serum level < 250 ng/L) were divided into two groups based on their treatment type: intramuscular cyanocobalamin (Group 1) and sublingual methylcobalamin (Group 2). Group 1 included 29 (9.3%) patients, and Group 2 included 283 (90.7%) patients, with 56 (18%) patients in Group 2 undergoing treatment for childhood cancer. The sublingual methylcobalamin protocol consisted of 1 puff (500 μg) daily for children under 8 years of age and 2 puffs (1000 μg) daily for those 8 years and older, administered for 1.5 months and then three times weekly for an additional 1.5 months. Results: The mean ages in Groups 1 and 2 were 10.07 ± 6.05 years (range, 1–17 years) and 7.43 ± 5.86 years (range, 0.1–17 years), respectively. The female/male ratio was 19/10 in Group 1 and 145/138 in Group 2. The most common diagnoses were anemia (72, 22.9%), cancer (56, 18.0%), and hemangioma (40, 12.7%). The median serum levels of vitamin B12 in Group 1 were 177 ng/L before treatment, 447 ng/L after 1.5 months, and 321.5 ng/L after 3 months. In Group 2, the levels were 172 ng/L before treatment, 438 ng/L after 1.5 months, and 360 ng/L after 3 months. There were no significant between-group differences. Both groups showed a statistically significant increase in levels above 300 ng/L. Discussion: Sublingual methylcobalamin, a noninvasive treatment option, was as effective as intramuscular cyanocobalamin. This study is to compare the standard intramuscular protocol with a new dosing regimen for sublingual methylcobalamin. This study showed that it is also useful for children to hold the spray in their mouths for 1 min and avoid food intake for the next 15 min. Full article
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12 pages, 1724 KiB  
Article
Simultaneous Determination of Three Active Forms of Vitamin B12 In Situ Produced During Fermentation by LC-MS/MS
by Zhihao Fan, Yajie Li, Xia Fan, Pei Wang, Runqiang Yang and Chong Xie
Foods 2025, 14(2), 309; https://doi.org/10.3390/foods14020309 - 17 Jan 2025
Cited by 2 | Viewed by 2047
Abstract
The in situ fortification of vitamin B12 (VB12) in foods through fermentation is an effective strategy to address the deficiency of this micronutrient, and precise monitoring of VB12 production is crucial for developing VB12-fortified functional foods. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) is advantageous [...] Read more.
The in situ fortification of vitamin B12 (VB12) in foods through fermentation is an effective strategy to address the deficiency of this micronutrient, and precise monitoring of VB12 production is crucial for developing VB12-fortified functional foods. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) is advantageous for analyzing trace substances in food due to its high sensitivity. In the present study, an LC-MS/MS method capable of rapidly and accurately quantifying three active forms of VB12, namely adenosylcobalamin (AdoCbl), methylcobalamin (MeCbl), hydroxocobalamin (OHCbl), in 8 min were developed. Meanwhile, the quantitative result of this method is not affected by pseudo-VB12 because the selected ion channels include fragments of active VB12. Maintaining light-shielding during extraction and purification is essential, as light exposure during the process can decrease the content of detected VB12 by about 30%. At last, the developed method was applied for the determination of VB12 in fermented rice bran and the cell mass of Propionibacterium freudenreichii. The results showed that AdoCbl was the predominant form of VB12 during fermentation, and the addition of cobalt did not influence the proportions of the three VB12 types. The present study reported a rapid and accurate method for the simultaneous determination of three active forms of VB12, which can effectively support the development of foods with VB12 fortification. Full article
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11 pages, 1274 KiB  
Article
Effect of Methylfolate, Pyridoxal-5′-Phosphate, and Methylcobalamin (SolowaysTM) Supplementation on Homocysteine and Low-Density Lipoprotein Cholesterol Levels in Patients with Methylenetetrahydrofolate Reductase, Methionine Synthase, and Methionine Synthase Reductase Polymorphisms: A Randomized Controlled Trial
by Evgeny Pokushalov, Andrey Ponomarenko, Sevda Bayramova, Claire Garcia, Inessa Pak, Evgenya Shrainer, Marina Ermolaeva, Dmitry Kudlay, Michael Johnson and Richard Miller
Nutrients 2024, 16(11), 1550; https://doi.org/10.3390/nu16111550 - 21 May 2024
Cited by 5 | Viewed by 4547
Abstract
Exploring the link between genetic polymorphisms in folate metabolism genes (MTHFR, MTR, and MTRR) and cardiovascular disease (CVD), this study evaluates the effect of B vitamin supplements (methylfolate, pyridoxal-5′-phosphate, and methylcobalamin) on homocysteine and lipid levels, potentially guiding personalized CVD risk management. In [...] Read more.
Exploring the link between genetic polymorphisms in folate metabolism genes (MTHFR, MTR, and MTRR) and cardiovascular disease (CVD), this study evaluates the effect of B vitamin supplements (methylfolate, pyridoxal-5′-phosphate, and methylcobalamin) on homocysteine and lipid levels, potentially guiding personalized CVD risk management. In a randomized, double-blind, placebo-controlled trial, 54 patients aged 40–75 with elevated homocysteine and moderate LDL-C levels were divided based on MTHFR, MTR, and MTRR genetic polymorphisms. Over six months, they received either a combination of methylfolate, P5P, and methylcobalamin, or a placebo. At the 6 months follow-up, the treatment group demonstrated a significant reduction in homocysteine levels by 30.0% (95% CI: −39.7% to −20.3%) and LDL-C by 7.5% (95% CI: −10.3% to −4.7%), compared to the placebo (p < 0.01 for all). In the subgroup analysis, Homozygous Minor Allele Carriers showed a more significant reduction in homocysteine levels (48.3%, 95% CI: −62.3% to −34.3%, p < 0.01) compared to mixed allele carriers (18.6%, 95% CI: −25.6% to −11.6%, p < 0.01), with a notable intergroup difference (29.7%, 95% CI: −50.7% to −8.7%, p < 0.01). LDL-C levels decreased by 11.8% in homozygous carriers (95% CI: −15.8% to −7.8%, p < 0.01) and 4.8% in mixed allele carriers (95% CI: −6.8% to −2.8%, p < 0.01), with a significant between-group difference (7.0%, 95% CI: −13.0% to −1.0%, p < 0.01). Methylfolate, P5P, and methylcobalamin supplementation tailored to genetic profiles effectively reduced homocysteine and LDL-C levels in patients with specific MTHFR, MTR, and MTRR polymorphisms, particularly with homozygous minor allele polymorphisms. Full article
(This article belongs to the Section Proteins and Amino Acids)
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28 pages, 2232 KiB  
Review
Emerging Roles of Vitamin B12 in Aging and Inflammation
by Sergey Yu. Simonenko, Daria A. Bogdanova and Nikita A. Kuldyushev
Int. J. Mol. Sci. 2024, 25(9), 5044; https://doi.org/10.3390/ijms25095044 - 6 May 2024
Cited by 10 | Viewed by 9133
Abstract
Vitamin B12 (cobalamin) is an essential nutrient for humans and animals. Metabolically active forms of B12-methylcobalamin and 5-deoxyadenosylcobalamin are cofactors for the enzymes methionine synthase and mitochondrial methylmalonyl-CoA mutase. Malfunction of these enzymes due to a scarcity of vitamin B [...] Read more.
Vitamin B12 (cobalamin) is an essential nutrient for humans and animals. Metabolically active forms of B12-methylcobalamin and 5-deoxyadenosylcobalamin are cofactors for the enzymes methionine synthase and mitochondrial methylmalonyl-CoA mutase. Malfunction of these enzymes due to a scarcity of vitamin B12 leads to disturbance of one-carbon metabolism and impaired mitochondrial function. A significant fraction of the population (up to 20%) is deficient in vitamin B12, with a higher rate of deficiency among elderly people. B12 deficiency is associated with numerous hallmarks of aging at the cellular and organismal levels. Cellular senescence is characterized by high levels of DNA damage by metabolic abnormalities, increased mitochondrial dysfunction, and disturbance of epigenetic regulation. B12 deficiency could be responsible for or play a crucial part in these disorders. In this review, we focus on a comprehensive analysis of molecular mechanisms through which vitamin B12 influences aging. We review new data about how deficiency in vitamin B12 may accelerate cellular aging. Despite indications that vitamin B12 has an important role in health and healthy aging, knowledge of the influence of vitamin B12 on aging is still limited and requires further research. Full article
(This article belongs to the Special Issue Functional Role of Cytokines in Cancer and Chronic Inflammation)
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17 pages, 1687 KiB  
Article
Kinetics of Cellular Cobalamin Uptake and Conversion: Comparison of Aquo/Hydroxocobalamin to Cyanocobalamin
by Sergey N. Fedosov, Ebba Nexo and Christian W. Heegaard
Nutrients 2024, 16(3), 378; https://doi.org/10.3390/nu16030378 - 27 Jan 2024
Cited by 5 | Viewed by 3451
Abstract
Cyanocobalamin (CNCbl) and aquo/hydroxocobalamin (HOCbl) are the forms of vitamin B12 that are most commonly used for supplementation. They are both converted to methylcobalamin (MeCbl) and 5′-deoxyadenosylcobalamin (AdoCbl), which metabolize homocysteine and methylmalonic acid, respectively. Here, we compare the kinetics of uptake [...] Read more.
Cyanocobalamin (CNCbl) and aquo/hydroxocobalamin (HOCbl) are the forms of vitamin B12 that are most commonly used for supplementation. They are both converted to methylcobalamin (MeCbl) and 5′-deoxyadenosylcobalamin (AdoCbl), which metabolize homocysteine and methylmalonic acid, respectively. Here, we compare the kinetics of uptake and the intracellular transformations of radiolabeled CNCbl vs. HOCbl in HeLa cells. More HOCbl was accumulated over 4–48 h, but further extrapolation indicated similar uptake (>90%) for both vitamin forms. The initially synthesized coenzyme was MeCbl, which noticeably exceeded AdoCbl during 48 h. Yet, the synthesis of AdoCbl accelerated, and the predicted final levels of Cbls were MeCbl ≈ AdoCbl ≈ 40% and HOCbl ≈ 20%. The designed kinetic model revealed the same patterns of the uptake and turnover for CNCbl and HOCbl, apart from two steps. First, the “activating” intracellular processing of the internalized HOCbl was six-fold faster. Second, the detachment rates from the cell surface (when the “excessive” Cbl-molecules were refluxed into the external medium) related as 4:1 for CNCbl vs. HOCbl. This gave a two-fold faster cellular accumulation and processing of HOCbl vs. CNCbl. In medical terms, our data suggest (i) an earlier response to the treatment of Cbl-deficiency with HOCbl, and (ii) the manifestation of a successful treatment initially as a decrease in homocysteine. Full article
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17 pages, 2216 KiB  
Article
Diet-Induced Severe Hyperhomocysteinemia Promotes Atherosclerosis Progression and Dysregulates the Plasma Metabolome in Apolipoprotein-E-Deficient Mice
by Stephen G. Andrews, Anthony M. Koehle, Devendra Paudel, Thomas Neuberger, A. Catharine Ross, Vishal Singh, Teodoro Bottiglieri and Rita Castro
Nutrients 2024, 16(3), 330; https://doi.org/10.3390/nu16030330 - 23 Jan 2024
Cited by 8 | Viewed by 3759
Abstract
Atherosclerosis and resulting cardiovascular disease are the leading causes of death in the US. Hyperhomocysteinemia (HHcy), or the accumulation of the intermediate amino acid homocysteine, is an independent risk factor for atherosclerosis, but the intricate biological processes mediating this effect remain elusive. Several [...] Read more.
Atherosclerosis and resulting cardiovascular disease are the leading causes of death in the US. Hyperhomocysteinemia (HHcy), or the accumulation of the intermediate amino acid homocysteine, is an independent risk factor for atherosclerosis, but the intricate biological processes mediating this effect remain elusive. Several factors regulate homocysteine levels, including the activity of several enzymes and adequate levels of their coenzymes, including pyridoxal phosphate (vitamin B6), folate (vitamin B9), and methylcobalamin (vitamin B12). To better understand the biological influence of HHcy on the development and progression of atherosclerosis, apolipoprotein-E-deficient (apoE−/− mice), a model for human atherosclerosis, were fed a hyperhomocysteinemic diet (low in methyl donors and B vitamins) (HHD) or a control diet (CD). After eight weeks, the plasma, aorta, and liver were collected to quantify methylation metabolites, while plasma was also used for a broad targeted metabolomic analysis. Aortic plaque burden in the brachiocephalic artery (BCA) was quantified via 14T magnetic resonance imaging (MRI). A severe accumulation of plasma and hepatic homocysteine and an increased BCA plaque burden were observed, thus confirming the atherogenic effect of the HHD. Moreover, a decreased methylation capacity in the plasma and aorta, indirectly assessed by the ratio of S-adenosylmethionine to S-adenosylhomocysteine (SAM:SAH) was detected in HHD mice together with a 172-fold increase in aortic cystathionine levels, indicating increased flux through the transsulfuration pathway. Betaine and its metabolic precursor, choline, were significantly decreased in the livers of HHD mice versus CD mice. Widespread changes in the plasma metabolome of HHD mice versus CD animals were detected, including alterations in acylcarnitines, amino acids, bile acids, ceramides, sphingomyelins, triacylglycerol levels, and several indicators of dysfunctional lipid metabolism. This study confirms the relevance of severe HHcy in the progression of vascular plaque and suggests novel metabolic pathways implicated in the pathophysiology of atherosclerosis. Full article
(This article belongs to the Special Issue Methyl Nutrients and One-Carbon Metabolism in Chronic Diseases)
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57 pages, 10028 KiB  
Review
The Miracle of Vitamin B12 Biochemistry
by Tudor Spataru
Reactions 2024, 5(1), 20-76; https://doi.org/10.3390/reactions5010002 - 5 Jan 2024
Cited by 5 | Viewed by 6464
Abstract
For decades, the comparison of experimental data with theoretical results in studying the biochemistry of vitamin B12 has been very confusing. While the methylcobalamin cofactor-dependent Methionine Synthase process can undergo unlimited turnovers, and some of the adenosylcobalamin-dependent processes run with close-to-unity equilibrium constants [...] Read more.
For decades, the comparison of experimental data with theoretical results in studying the biochemistry of vitamin B12 has been very confusing. While the methylcobalamin cofactor-dependent Methionine Synthase process can undergo unlimited turnovers, and some of the adenosylcobalamin-dependent processes run with close-to-unity equilibrium constants (e.g., with close-to-zero energy barriers), the DFT and QM/MM based on density functional theory, the most used and appreciated methods for calculating the electronic structure of molecules, have been showing a much shorter than experimental-determined Co-N distances in the vitamin B12 cofactors of Co+2 and the inadequate large energetic barriers of their enzymology bioprocesses. The confusion was even larger since some in vitro experimental data showed large barriers to the vitamin B12 cofactor reactions (which in fact play a destructive role in the Methionine Synthase process and which barriers were caused mostly by the influence of the solvents in which the reaction took place). It reached the point where solid contributions to the study of the biochemical processes of vitamin B12 were almost officially questioning the correctness of the experimental determination of the Co-N chemical bond distances in the cobalt(II) cofactors of vitamin B12. Unexpectedly, all the theoretical biochemistry of the vitamin B12 cofactors began to agree with all in vivo experimental data only when they were treated with the MCSCF method, the method that considers the orbital mixing, or in other words, the Pseudo-Jahn–Teller Effect. MCSCF data establish unknown mechanistic details of the methyl radical and hydrogen transfers, the origin of the electronic transfers between bioreagents, and the nature and the relationship between the bioreactions. The Pseudo-Jahn–Teller Effect, e.g., orbital mixing, governs vitamin B12 chemistry in general and provides insight into particular details of vitamin B12-dependent reactions in the human body. It turns out that the DFT or QM/MM based on DFT method theoretical data are incongruent with the experimental data due to their limitations, e.g., the unaccounted-for effects of orbital mixing. Full article
(This article belongs to the Special Issue Feature Papers in Reactions in 2023)
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12 pages, 4527 KiB  
Article
Interaction of Glutathione with MMACHC Arginine-Rich Pocket Variants Associated with Cobalamin C Disease: Insights from Molecular Modeling
by Priya Antony, Bincy Baby, Amanat Ali, Ranjit Vijayan and Fatma Al Jasmi
Biomedicines 2023, 11(12), 3217; https://doi.org/10.3390/biomedicines11123217 - 4 Dec 2023
Cited by 3 | Viewed by 1938
Abstract
Methylmalonic aciduria and homocystinuria type C protein (MMACHC) is required by the body to metabolize cobalamin (Cbl). Due to its complex structure and cofactor forms, Cbl passes through an extensive series of absorptive and processing steps before being delivered to mitochondrial methyl malonyl-CoA [...] Read more.
Methylmalonic aciduria and homocystinuria type C protein (MMACHC) is required by the body to metabolize cobalamin (Cbl). Due to its complex structure and cofactor forms, Cbl passes through an extensive series of absorptive and processing steps before being delivered to mitochondrial methyl malonyl-CoA mutase and cytosolic methionine synthase. Depending on the cofactor attached, MMACHC performs either flavin-dependent reductive decyanation or glutathione (GSH)-dependent dealkylation. The alkyl groups of Cbl have to be removed in the presence of GSH to produce intermediates that can later be converted into active cofactor forms. Pathogenic mutations in the GSH binding site, such as R161Q, R161G, R206P, R206W, and R206Q, have been reported to cause Cbl diseases. The impact of these variations on MMACHC’s structure and how it affects GSH and Cbl binding at the molecular level is poorly understood. To better understand the molecular basis of this interaction, mutant structures involving the MMACHC-MeCbl-GSH complex were generated using in silico site-directed point mutations and explored using molecular dynamics (MD) simulations. The results revealed that mutations in the key arginine residues disrupt GSH binding by breaking the interactions and reducing the free energy of binding of GSH. Specifically, variations at position 206 appeared to produce weaker GSH binding. The lowered binding affinity for GSH in the variant structures could impact metabolic pathways involving Cbl and its trafficking. Full article
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23 pages, 18615 KiB  
Article
Potent Antiviral Activity of Vitamin B12 against Severe Acute Respiratory Syndrome Coronavirus 2, Middle East Respiratory Syndrome Coronavirus, and Human Coronavirus 229E
by Yassmin Moatasim, Omnia Kutkat, Ahmed M. Osman, Mokhtar R. Gomaa, Faten Okda, Mohamed El Sayes, Mina Nabil Kamel, Mohamed Gaballah, Ahmed Mostafa, Rabeh El-Shesheny, Ghazi Kayali, Mohamed A. Ali and Ahmed Kandeil
Microorganisms 2023, 11(11), 2777; https://doi.org/10.3390/microorganisms11112777 - 15 Nov 2023
Cited by 6 | Viewed by 5675
Abstract
Repurposing vitamins as antiviral supporting agents is a rapid approach used to control emerging viral infections. Although there is considerable evidence supporting the use of vitamin supplementation in viral infections, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the specific role of each [...] Read more.
Repurposing vitamins as antiviral supporting agents is a rapid approach used to control emerging viral infections. Although there is considerable evidence supporting the use of vitamin supplementation in viral infections, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the specific role of each vitamin in defending against coronaviruses remains unclear. Antiviral activities of available vitamins on the infectivity and replication of human coronaviruses, namely, SARS-CoV-2, Middle East respiratory syndrome coronavirus (MERS-CoV), and human coronavirus 229E (HCoV-229E), were investigated using in silico and in vitro studies. We identified potential broad-spectrum inhibitor effects of Hydroxocobalamin and Methylcobalamin against the three tested CoVs. Cyanocobalamin could selectively affect SARS-CoV-2 but not MERS-CoV and HCoV-229E. Methylcobalamin showed significantly higher inhibition values on SARS-CoV-2 compared with Hydroxocobalamin and Cyanocobalamin, while Hydroxocobalamin showed the highest potent antiviral activity against MERS-CoV and Cyanocobalamin against HCoV-229E. Furthermore, in silico studies were performed for these promising vitamins to investigate their interaction with SARS-CoV-2, MERS-CoV, and HCoV-229E viral-specific cell receptors (ACE2, DPP4, and hAPN protein, respectively) and viral proteins (S-RBD, 3CL pro, RdRp), suggesting that Hydroxocobalamin, Methylcobalamin, and Cyanocobalamin may have significant binding affinity to these proteins. These results show that Methylcobalamin may have potential benefits for coronavirus-infected patients. Full article
(This article belongs to the Section Virology)
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19 pages, 5307 KiB  
Article
Methylcobalamin in Combination with Early Intervention of Low-Intensity Pulsed Ultrasound Potentiates Nerve Regeneration and Functional Recovery in a Rat Brachial Plexus Injury Model
by Yueh-Ling Hsieh, Yu-Lin Lu, Nian-Pu Yang and Chen-Chia Yang
Int. J. Mol. Sci. 2023, 24(18), 13856; https://doi.org/10.3390/ijms241813856 - 8 Sep 2023
Cited by 1 | Viewed by 3215
Abstract
This study evaluated and compared the functional recovery and histopathological outcomes of treatment involving low-intensity pulsed ultrasound (LIPUS) and methylcobalamin (B12) on brachial plexus injury (BPI) in an experimental rat model. Three days after BPI, the rats were assigned to receive either LIPUS [...] Read more.
This study evaluated and compared the functional recovery and histopathological outcomes of treatment involving low-intensity pulsed ultrasound (LIPUS) and methylcobalamin (B12) on brachial plexus injury (BPI) in an experimental rat model. Three days after BPI, the rats were assigned to receive either LIPUS or methylcobalamin alone or in combination consecutively for 12 days. Serial changes in sensory and motor behavioral responses, as well as morphological and immunohistochemical changes for substance P (SP), ionized calcium-binding adapter molecule 1 (iba1), brain-derived neurotrophic factor (BDNF), and S100 were examined 28 days after BPI as the outcome measurements. Early intervention of LIPUS and methylcobalamin, whether alone or in combination, augmented the sensory and motor behavioral recovery as well as modulated SP and iba1 expression in spinal dorsal horns, BDNF, and S100 in the injured nerve. Moreover, the combined therapy with its synergistic effect gave the most beneficial effect in accelerating functional recovery. In view of the effective initiation of early recovery of sensory and motor functions, treatment with LIPUS and methylcobalamin in combination has a potential role in the clinical management of early-phase BPI. Full article
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12 pages, 2071 KiB  
Article
The First Step and the Cob(II)alamin Cofactor Inactive Particles Reactivation in the Updated Mechanism of the Methionine Synthase Process
by Tudor Spataru
Reactions 2023, 4(2), 274-285; https://doi.org/10.3390/reactions4020016 - 22 May 2023
Cited by 2 | Viewed by 1990
Abstract
The Methionine Synthase process, in principle, can take an unlimited number of turnovers in the presence of the AdoMet substrate. In the absence of this substrate, the Methionine Synthase process lasts only about 2000 turnovers. During 2000 turnovers, the entire amount of methylcob(II)alamin [...] Read more.
The Methionine Synthase process, in principle, can take an unlimited number of turnovers in the presence of the AdoMet substrate. In the absence of this substrate, the Methionine Synthase process lasts only about 2000 turnovers. During 2000 turnovers, the entire amount of methylcob(II)alamin cofactor is converted into inactive cob(II)alamin particles. Nevertheless, the mechanism of the Methionine Synthase process determined previously lacks the presence of the AdoMet substrate. On the other hand, the first step of this mechanism was only mentioned earlier without its analysis. The CASSCF geometry optimization of the inactive cob(II)alamin cofactor particle plus the AdoMet ion substrate and of the methylcob(II)alamin cofactor particle plus homocysteine ion and histidine molecule joint models have been performed. CASSCF calculations show that the AdoMet particle transfers the methyl radical to the biologically inactive cob(II)alamin particle during their interaction, transforming it into the biologically active particle of methylcob(II)alamin. CASSCF geometry optimization of the second model leads to the Co-N bond’s full cleavage. The two processes take place in the absence of the total energy barrier. The fully updated mechanism of the Methionine Synthase process has been drawn. Full article
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29 pages, 5462 KiB  
Article
Preparation, Characterization, and Evaluation of Cytotoxicity of Fast Dissolving Hydrogel Based Oral Thin Films Containing Pregabalin and Methylcobalamin
by Emrah Özakar, Rukiye Sevinç-Özakar and Bilal Yılmaz
Gels 2023, 9(2), 147; https://doi.org/10.3390/gels9020147 - 9 Feb 2023
Cited by 10 | Viewed by 5653
Abstract
The oral availability of many drugs is problematic due to the pH of the stomach, enzymes, and first-pass effects through the liver. However, especially geriatric, pediatric, bedridden, or mentally handicapped patients and those with dysphagia have difficulty swallowing or chewing solid dosage forms. [...] Read more.
The oral availability of many drugs is problematic due to the pH of the stomach, enzymes, and first-pass effects through the liver. However, especially geriatric, pediatric, bedridden, or mentally handicapped patients and those with dysphagia have difficulty swallowing or chewing solid dosage forms. Oral Thin Films (OTFs) are one of the new drug delivery systems that can solve these problems. Pregabalin (PG) and Methylcobalamin (MC), which are frequently preferred for pain originating in the central nervous system, were brought together for the first time using OTF technology in this study. In this study, a quantification method for PG and MC was developed and validated simultaneously. Optimum formulations were selected with organoleptic and morphological controls, moisture absorption capacity, swelling capacity, percent elongation, foldability, pH, weight variability, thickness, disintegration time, and transparency tests on OTFs prepared by the solvent pouring method. Content uniformity, dissolution rate, determination of release kinetics, SEM, XRD, FT-IR, DSC, long-term stability, and cytotoxicity studies on the tongue epithelial cell line (SCC-9) were performed on selected OTFs. As a result, OTFs containing PG-MC, which are non-toxic, highly flexible, transparent, compatible with intraoral pH, with fast disintegration time (<30 s), and acceptable in taste and appearance, have been developed successfully. Full article
(This article belongs to the Special Issue The Role of Mucus Gel Layer in Drug and Nutraceutical Delivery)
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30 pages, 2828 KiB  
Review
Vitamin B12 in Foods, Food Supplements, and Medicines—A Review of Its Role and Properties with a Focus on Its Stability
by Žane Temova Rakuša, Robert Roškar, Neal Hickey and Silvano Geremia
Molecules 2023, 28(1), 240; https://doi.org/10.3390/molecules28010240 - 28 Dec 2022
Cited by 49 | Viewed by 24395
Abstract
Vitamin B12, also known as the anti-pernicious anemia factor, is an essential micronutrient totally dependent on dietary sources that is commonly integrated with food supplements. Four vitamin B12 forms—cyanocobalamin, hydroxocobalamin, 5′-deoxyadenosylcobalamin, and methylcobalamin—are currently used for supplementation and, here, we [...] Read more.
Vitamin B12, also known as the anti-pernicious anemia factor, is an essential micronutrient totally dependent on dietary sources that is commonly integrated with food supplements. Four vitamin B12 forms—cyanocobalamin, hydroxocobalamin, 5′-deoxyadenosylcobalamin, and methylcobalamin—are currently used for supplementation and, here, we provide an overview of their biochemical role, bioavailability, and efficacy in different dosage forms. Since the effective quantity of vitamin B12 depends on the stability of the different forms, we further provide a review of their main reactivity and stability under exposure to various environmental factors (e.g., temperature, pH, light) and the presence of some typical interacting compounds (oxidants, reductants, and other water-soluble vitamins). Further, we explore how the manufacturing process and storage affect B12 stability in foods, food supplements, and medicines and provide a summary of the data published to date on the content-related quality of vitamin B12 products on the market. We also provide an overview of the approaches toward their stabilization, including minimization of the destabilizing factors, addition of proper stabilizers, or application of some (innovative) technological processes that could be implemented and contribute to the production of high-quality vitamin B12 products. Full article
(This article belongs to the Special Issue Bioactive Ingredients in the Food Matrix)
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17 pages, 3950 KiB  
Article
Improvement of the Clinical and Psychological Profile of Patients with Autism after Methylcobalamin Syrup Administration
by Adela Čorejová, Tomáš Fazekaš, Daniela Jánošíková, Juraj Repiský, Veronika Pospíšilová, Maria Miková, Drahomíra Rauová, Daniela Ostatníková, Ján Kyselovič and Anna Hrabovská
Nutrients 2022, 14(10), 2035; https://doi.org/10.3390/nu14102035 - 12 May 2022
Cited by 7 | Viewed by 4139
Abstract
(1) Background: Autism, also known as autism-spectrum disorder, is a pervasive developmental disorder affecting social skills and psychological status in particular. The complex etiopathogenesis of autism limits efficient therapy, which leads to problems with the normal social integration of the individual and causes [...] Read more.
(1) Background: Autism, also known as autism-spectrum disorder, is a pervasive developmental disorder affecting social skills and psychological status in particular. The complex etiopathogenesis of autism limits efficient therapy, which leads to problems with the normal social integration of the individual and causes severe family distress. Injectable methylcobalamin was shown to improve the clinical status of patients via enhanced cell oxidative status and/or methylation capacity. Here we tested the efficiency of a syrup form of methylcobalamin in treating autism. (2) Methods: Methylcobalamin was administered daily at 500 µg dose to autistic children and young adults (n = 25) during a 200-day period. Clinical and psychological status was evaluated by parents and psychologists and plasma levels of reduced and oxidized glutathione, vitamin B12, homocysteine, and cysteine were determined before the treatment, and at day 100 and day 200 of the treatment. (3) Results: Good patient compliance was reported. Methylcobalamin treatment gradually improved the overall clinical and psychological status, with the highest impact in the social domain, followed by the cognitive, behavioral and communication characteristics. Changes in the clinical and psychological status were strongly associated with the changes in the level of reduced glutathione and reduced/oxidized glutathione ratio. (4) Conclusion: A high dose of methylcobalamin administered in syrup form ameliorates the clinical and psychological status of autistic individuals, probably due to the improved oxidative status. Full article
(This article belongs to the Section Clinical Nutrition)
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Review
The Effectiveness of Cobalamin (B12) Treatment for Autism Spectrum Disorder: A Systematic Review and Meta-Analysis
by Daniel A. Rossignol and Richard E. Frye
J. Pers. Med. 2021, 11(8), 784; https://doi.org/10.3390/jpm11080784 - 11 Aug 2021
Cited by 45 | Viewed by 12500
Abstract
Autism spectrum disorder (ASD) is a common neurodevelopmental disorder affecting 2% of children in the United States. Biochemical abnormalities associated with ASD include impaired methylation and sulphation capacities along with low glutathione (GSH) redox capacity. Potential treatments for these abnormalities include cobalamin (B12). [...] Read more.
Autism spectrum disorder (ASD) is a common neurodevelopmental disorder affecting 2% of children in the United States. Biochemical abnormalities associated with ASD include impaired methylation and sulphation capacities along with low glutathione (GSH) redox capacity. Potential treatments for these abnormalities include cobalamin (B12). This systematic review collates the studies using B12 as a treatment in ASD. A total of 17 studies were identified; 4 were double-blind, placebo-controlled studies (2 examined B12 injections alone and 2 used B12 in an oral multivitamin); 1 was a prospective controlled study; 6 were prospective, uncontrolled studies, and 6 were retrospective (case series and reports). Most studies (83%) used oral or injected methylcobalamin (mB12), while the remaining studies did not specify the type of B12 used. Studies using subcutaneous mB12 injections (including 2 placebo-controlled studies) used a 64.5–75 µg/kg/dose. One study reported anemia in 2 ASD children with injected cyanocobalamin that resolved with switching to injected mB12. Two studies reported improvements in markers of mitochondrial metabolism. A meta-analysis of methylation metabolites demonstrated decreased S-adenosylhomocysteine (SAH), and increased methionine, S-adenosylmethionine (SAM), SAM/SAH ratio, and homocysteine (with small effect sizes) with mB12. Meta-analysis of the transsulfuration and redox metabolism metabolites demonstrated significant improvements with mB12 in oxidized glutathione (GSSG), cysteine, total glutathione (GSH), and total GSH/GSSG redox ratio with medium to large effect sizes. Improvements in methylation capacity and GSH redox ratio were significantly associated with clinical improvements (with a mean moderate effect size of 0.59) in core and associated ASD symptoms, including expressive communication, personal and domestic daily living skills, and interpersonal, play-leisure, and coping social skills, suggesting these biomarkers may predict response to B12. Other clinical improvements observed with B12 included sleep, gastrointestinal symptoms, hyperactivity, tantrums, nonverbal intellectual quotient, vision, eye contact, echolalia, stereotypy, anemia, and nocturnal enuresis. Adverse events identified by meta-analysis included hyperactivity (11.9%), irritability (3.4%), trouble sleeping (7.6%), aggression (1.8%), and worsening behaviors (7.7%) but were generally few, mild, not serious, and not significantly different compared to placebo. In one study, 78% of parents desired to continue mB12 injections after the study conclusion. Preliminary clinical evidence suggests that B12, particularly subcutaneously injected mB12, improves metabolic abnormalities in ASD along with clinical symptoms. Further large multicenter placebo-controlled studies are needed to confirm these data. B12 is a promising treatment for ASD. Full article
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