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2.
Front Biosci (Elite Ed) ; 15(2): 10, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37369571

RESUMO

BACKGROUND: Information on the contents of both vitamin B12 and folate in edible seaweeds is limited, of which deficiencies disrupt methionine biosynthesis to accumulate homocysteine as a risk factor of cardiovascular diseases. METHODS: Both vitamins were determined in commercially available edible seaweed products using high-performance liquid chromatography. RESULTS: Dried purple laver (Neopyropia yezoensis) products contain higher levels of vitamin B12 (approximately 30-60 µg/100 g dry weight) and folate compounds (approximately 880-1300 µg/100 g dry weight) than other seaweed products, such as kombu (Saccharina japonica), hijiki (Sargassum fusiformis), and wakame (Undaria pinnatifida). 5-methyltetrahydrofolate was the major folate compound in purple laver products. 5-formyltetrahydrofolate was found at a moderate level, whereas tetrahydrofolate, 5,10-metenyltetrahydrofolate, 10-formyltetrahydrofolate, and folic acid were found to be minor folate compounds. CONCLUSIONS: These findings suggest that dried purple laver (nori) products are suitable sources of vitamin B12 and folate compounds for humans, especially vegetarians.


Assuntos
Alga Marinha , Vitamina B 12 , Humanos , Vitamina B 12/análise , Vitamina B 12/química , Ácido Fólico , Alga Marinha/química , Vitaminas/análise , Cromatografia Líquida de Alta Pressão
3.
Cureus ; 15(4): e38245, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37252510

RESUMO

Background Intraoperative hypofibrinogenemia is a major factor associated with increased postoperative blood loss in adult cardiac surgery. However, previous pediatric studies on this topic did not sufficiently adjust for potential confounders and variations in surgeons' techniques. Therefore, evidence for the association between hypofibrinogenemia and postoperative blood loss after cardiac surgery in children remains insufficient. In this study, we aimed to evaluate the association between postoperative blood loss and hypofibrinogenemia by adjusting for potential confounders and the effects of differences in surgeons' techniques. Methodology This single-center, retrospective, cohort study included children who underwent cardiac surgery with cardiopulmonary bypass from April 2019 to March 2022. Multilevel logistic regression models with mixed effects were used to evaluate the association of major blood loss in the first six hours postoperatively with fibrinogen concentration at the end of cardiopulmonary bypass. The difference in the surgeon's techniques was adjusted as a random effect for the model. The model included potential confounders identified as risk factors in previous studies. Results A total of 401 patients were included. A fibrinogen concentration ≤150 mg/dL (adjusted odds ratio (aOR) = 2.08; 95% confidence interval (CI) = 1.18-3.67; p = 0.011) and the presence of cyanotic disease (aOR = 2.34; 95% CI = 1.10-4.97; p = 0.027) were associated with major blood loss in the first six postoperative hours. Conclusions A fibrinogen concentration ≤150 mg/dL and the presence of cyanotic disease were associated with postoperative blood loss in pediatric cardiac surgery. Maintaining a fibrinogen concentration >150 mg/dL is recommended, especially for patients with cyanotic diseases.

4.
Saudi J Anaesth ; 17(1): 1-6, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37032690

RESUMO

Introduction: Sudden oxygen supply failure (OSF) is a life-threatening consequence that may be triggered by natural disasters. Anesthesiologists are required to manage OSF promptly in such catastrophic situations. However, the current evidence regarding the efficacy of anesthesia training for sudden OSF is insufficient. This preliminary study aimed to introduce our in-situ simulation training utilizing evaluation checklists for a sudden OSF situation during general anesthesia and to evaluate the efficacy of the training program for anesthesia providers. Methods: This is a preliminary single-center, prospective study. We developed an OSF simulation scenario utilizing evaluation checklists with key actions to manage OSF. The training session comprised four components: orientation, benchmark evaluation (pre-test) according to the checklists, a short didactic lecture, and post-lecture evaluation (post-test). The scenario comprised two steps wherein the participants were supposed to utilize different oxygen supply sources immediately after OSF (Step 1) and minimize the amount of oxygen consumption (Step 2). Results: Fifteen anesthesia providers were enrolled. The score for all anesthesia providers in the post-test was significantly higher than that in the pre-test (median 8 [IQR: 8, 8], 3 [IQR: 3, 4], P < 0.001, respectively). The successful performance rates of all anesthesia providers in one key action of all the four in Step 1 and four of all the six in Step 2 were significantly higher in the post-test than in the pre-test. Conclusions: Our in-situ training method utilizing evaluation checklists for a sudden OSF situation improved overall performance of anesthesia providers.

5.
Biosci Biotechnol Biochem ; 87(7): 717-723, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37096382

RESUMO

S-Adenosyl-L-methionine (SAM) and S-adenosyl-L-homocysteine (SAH) are important biochemical intermediates. SAM is the major methyl donor for diverse methylation reactions in vivo. The SAM to SAH ratio serves as a marker of methylation capacity. Stable isotope-labeled SAM and SAH are used to measure this ratio with high sensitivity. SAH hydrolase (EC 3.13.2.1; SAHH), which reversibly catalyzes the conversion of adenosine and L-homocysteine to SAH, is used to produce labeled SAH. To produce labeled SAH with high efficiency, we focused on the SAHH of Pyrococcus horikoshii OT3, a thermophilic archaeon. We prepared recombinant P. horikoshii SAHH using Escherichia coli and investigated its enzymatic properties. Unexpectedly, the optimum temperature and thermostability of P. horikoshii SAHH were much lower than its optimum growth temperature. However, addition of NAD+ to the reaction mixture shifted the optimum temperature of P. horikoshii SAHH to a higher temperature, suggesting that NAD+ stabilizes the structure of the enzyme.


Assuntos
NAD , Pyrococcus horikoshii , Pyrococcus horikoshii/metabolismo , S-Adenosil-Homocisteína/química , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo , Homocisteína , Hidrolases/metabolismo
6.
BMJ Open ; 13(4): e067554, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37068905

RESUMO

INTRODUCTION: Failure to secure an airway during general anaesthesia is a major cause of adverse events (AEs) in children. The safety of paediatric anaesthesia may be improved by identifying the incidence of AEs and their attributed risk factors. The aim of the current study is to obtain real-world data on the incidence of adverse peri-intubation events and assess their association with patient characteristics (including the prevalence of difficult airway features) and choice of anaesthesia management. These data can be used to develop a targeted education programme for anaesthesia providers towards quality improvement activities. METHODS AND ANALYSIS: This prospective, multicentre, registry-based, cross-sectional study will be conducted in four tertiary care hospitals in Japan from June 2022 to May 2025. Children <18 years of age undergoing surgical and/or diagnostic test procedures under general anaesthesia or sedation by anaesthesiologists will be enrolled in this study. Data on patient characteristics, discipline of anaesthesia providers and methodology of airway management will be collected through a standardised verification system. The exposure of interest is the presence of difficult airway features defined based on the craniofacial appearance. The primary and secondary endpoints are all AEs associated with airway management and reduced peripheral capillary oxygen saturation values. Potential confounders are related to the failure to secure the airway and variations in the anaesthesia providers' levels, adjusted using hierarchical multivariable regression models with mixed effects. The sample size was calculated to be approximately 16 000 assuming a 99% probability of obtaining a 95% Wilson CI with±0.3% of the half-width for the 2.0% of the incidence of critical AEs. ETHICS AND DISSEMINATION: The study protocol was approved by the Institutional Review Board at Aichi Children's Health and Medical Center (2021051). The results will be reported in a peer-reviewed journal and a relevant academic conference. TRIAL REGISTRATION NUMBER: UMIN000047351.


Assuntos
Manuseio das Vias Aéreas , Anestesia Geral , Criança , Humanos , Estudos Transversais , Estudos Prospectivos , Japão/epidemiologia , Manuseio das Vias Aéreas/efeitos adversos , Manuseio das Vias Aéreas/métodos , Anestesia Geral/efeitos adversos , Anestesia Geral/métodos , Sistema de Registros , Estudos Multicêntricos como Assunto
7.
Pediatr Int ; 65(1): e15446, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36528863

RESUMO

BACKGROUND: In pediatric catheterization, the palpation and landmark (PL) technique is widely used for femoral arterial and venous (FAV) cannulation. Over the past decade, the ultrasound-guided (US) technique has replaced the PL technique. This study aimed to assess the clinical impact of application of the US technique on the success rate and completion time of FAV cannulation during cardiac catheterization in children. METHODS: This is a retrospective observational study of consecutive pediatric patients who underwent cardiac catheterization in a tertiary care children's hospital from April 2016 to March 2022. The association between FAV cannulation success rate and the US technique was analyzed using multiple logistic regression analysis by adjusting for potential confounders, including patient and operator characteristics and procedural details. RESULTS: A total of 749 patients (PL, 378; US, 371) were analyzed. The odds ratio (OR) of the US technique success rate for FAV cannulation was 2.03, 95% confidence interval (CI), 1.10-3.73; p = 0.02. The OR of the cannulation success rate of children aged <1 year was 0.16 (95% CI, 0.03-0.97; p = 0.046). CONCLUSIONS: The US-guided technique was associated with an increased success rate of FAV cannulation, compared with the PL technique. Moreover, age < 1 year was an independent factor associated with a lower success rate of FAV cannulation. The US-guided technique might be an effective procedure in FAV cannulation during cardiac catheterization in children.


Assuntos
Cateterismo Venoso Central , Ultrassonografia de Intervenção , Criança , Humanos , Ultrassonografia de Intervenção/métodos , Ultrassonografia , Cateterismo Cardíaco , Artérias , Veias , Cateterismo Venoso Central/métodos
8.
J Sci Food Agric ; 103(7): 3685-3690, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36321533

RESUMO

BACKGROUND: Vitamin B12 is an essential vitamin that is absent in plant-derived foods such as fruits and vegetables. This can result in an increased risk of developing vitamin B12 deficiency in strict vegetarians (vegans). There are several studies that have aimed to enhance nutrients in food crops. The purpose of the present study was to fortify tomato fruits with vitamin B12 (or cyanocobalamin). RESULTS: Tomato plants were grown for 70 days in hydroponic culture pots and treated with 5 µm of cyanocobalamin on days 1-24 after the fruiting, and then harvested for tomato fruits. The ripened tomato fruits contained 4.0 × 10-7  g of cyanocobalamin per 100 g of dry weight and showed a significant increase in glucose and lycopene levels. CONCLUSION: The present study highlights the use of a cyanocobalamin-supplementation system for the production of B12 fortified tomato fruits that can help prevent B12 deficiency in vegetarians. © 2022 Society of Chemical Industry.


Assuntos
Solanum lycopersicum , Hidroponia , Frutas/química , Vitamina B 12/análise , Vitaminas/análise
9.
J Med Chem ; 65(18): 12427-12444, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36066182

RESUMO

Kinase fusions involving tropomyosin receptor kinases (TRKs) have been proven to act as strong oncogenic drivers and are therefore recognized as attractive therapeutic targets. We screened an in-house kinase-focused library and identified a promising hit compound with a unique tetracyclic scaffold. Compound 1 showed high TRK selectivity but moderate cell growth inhibitory activity as well as a potential risk of inducing CYP3A4. In this report, chemical modification intended to improve TRK inhibition and avoid CYP3A4 induction enabled us to identify an orally bioavailable, selective, and potent TRK inhibitor 7.


Assuntos
Neoplasias , Tropomiosina , Proliferação de Células , Citocromo P-450 CYP3A , Humanos , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/química , Receptor trkA
10.
Saudi J Anaesth ; 16(1): 34-37, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35261586

RESUMO

Background: A combination of dexmedetomidine and propofol is considered advantageous for maintaining spontaneous breathing with a satisfactory depth of anesthesia. However, the incidence of upper airway obstruction under sedation with dexmedetomidine and propofol in patients with Fontan circulation remains unanswered. This study aimed to evaluate upper airway patency and oxygen desaturation during sedation with dexmedetomidine and propofol for cardiac catheterization in pediatric patients with Fontan circulation. Methods: In this descriptive study, we reviewed medical records of patients with Fontan circulation who underwent cardiac catheterization between December 2018 and August 2020 at a single-center 200-bed academic children's hospital in Japan. Results: A total of 35 patients with Fontan circulation sedated with a departmental protocol of dexmedetomidine and propofol infusion for cardiac catheterization were reviewed. Overall, the incidence of airway interventions and oxygen desaturation were 31.4% and 28.6%, respectively. In children with a history of snoring and additional use of intravenous midazolam, the rates of airway interventions were 50% and 100%, respectively. In patients ≤2 years old with recent upper respiratory infection (URI) symptoms, oxygen desaturation rate was 75%. Conclusions: In children with Fontan circulation, the incidence rate of upper airway obstruction was high under sedation with dexmedetomidine and propofol during cardiac catheterization, which is commonly considered safe in children without Fontan circulation. A history of snoring, an additional bolus of IV midazolam, and the presence of recent URI symptoms in patients ≤2 years old are potential risks for upper airway obstruction.

12.
Int J Mol Sci ; 22(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34884761

RESUMO

(1) Background: Vitamin B12 deficiency in Caenorhabditis elegans results in severe oxidative stress and induces morphological abnormality in mutants due to disordered cuticle collagen biosynthesis. We clarified the underlying mechanism leading to such mutant worms due to vitamin B12 deficiency. (2) Results: The deficient worms exhibited decreased collagen levels of up to approximately 59% compared with the control. Although vitamin B12 deficiency did not affect the mRNA expression of prolyl 4-hydroxylase, which catalyzes the formation of 4-hydroxyproline involved in intercellular collagen biosynthesis, the level of ascorbic acid, a prolyl 4-hydroxylase coenzyme, was markedly decreased. Dityrosine crosslinking is involved in the extracellular maturation of worm collagen. The dityrosine level of collagen significantly increased in the deficient worms compared with the control. However, vitamin B12 deficiency hardly affected the mRNA expression levels of bli-3 and mlt-7, which are encoding crosslinking-related enzymes, suggesting that deficiency-induced oxidative stress leads to dityrosine crosslinking. Moreover, using GMC101 mutant worms that express the full-length human amyloid ß, we found that vitamin B12 deficiency did not affect the gene and protein expressions of amyloid ß but increased the formation of dityrosine crosslinking in the amyloid ß protein. (3) Conclusions: Vitamin B12-deficient wild-type worms showed motility dysfunction due to decreased collagen levels and the formation of highly tyrosine-crosslinked collagen, potentially reducing their flexibility. In GMC101 mutant worms, vitamin B12 deficiency-induced oxidative stress triggers dityrosine-crosslinked amyloid ß formation, which might promote its stabilization and toxic oligomerization.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Colágeno/metabolismo , Vitamina B 12/metabolismo , Peptídeos beta-Amiloides/química , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/biossíntese , Proteínas de Caenorhabditis elegans/química , Colágeno/biossíntese , Colágeno/química , Reagentes de Ligações Cruzadas/química , Reagentes de Ligações Cruzadas/metabolismo , Mutação , Estresse Oxidativo , RNA de Helmintos/genética , RNA de Helmintos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tirosina/análogos & derivados , Tirosina/química , Tirosina/metabolismo , Deficiência de Vitamina B 12/genética , Deficiência de Vitamina B 12/metabolismo
13.
Biosci Biotechnol Biochem ; 85(10): 2185-2190, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34410296

RESUMO

Backhousia citriodora (lemon myrtle) extract has been found to inhibit glucansucrase activity, which plays an important role in biofilm formation by Streptococcus mutans. In addition to glucansucrase, various virulence factors in S. mutans are involved in the initiation of caries. Lactate produced by S. mutans demineralizes the tooth enamel. This study investigated whether lemon myrtle extract can inhibit S. mutans lactate production. Lemon myrtle extract reduced the glycolytic pH drop in S. mutans culture and inhibited lactate production by at least 46%. Ellagic acid, quercetin, hesperetin, and myricetin, major polyphenols in lemon myrtle, reduced the glycolytic pH drop and lactate production, but not lactate dehydrogenase activity. Furthermore, these polyphenols reduced the viable S. mutans cell count. Thus, lemon myrtle extracts may inhibit S. mutans-mediated acidification of the oral cavity, thereby preventing dental caries and tooth decay.


Assuntos
Streptococcus mutans , Biofilmes , Ácido Láctico , Boca , Myrtus
15.
Antioxidants (Basel) ; 10(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203911

RESUMO

High homocysteine (Hcy) levels, mainly caused by vitamin B12 deficiency, have been reported to induce amyloid-ß (Aß) formation and tau hyperphosphorylation in mouse models of Alzheimer's disease. However, the relationship between B12 deficiency and Aß aggregation is poorly understood, as is the associated mechanism. In the current study, we used the transgenic C. elegans strain GMC101, which expresses human Aß1-42 peptides in muscle cells, to investigate the effects of B12 deficiency on Aß aggregation-associated paralysis. C. elegans GMC101 was grown on nematode growth medium with or without B12 supplementation or with 2-O-α-D-glucopyranosyl-L-ascorbic acid (AsA-2G) supplementation. The worms were age-synchronized by hypochlorite bleaching and incubated at 20 °C. After the worms reached the young adult stage, the temperature was increased to 25 °C to induce Aß production. Worms lacking B12 supplementation exhibited paralysis faster and more severely than those that received it. Furthermore, supplementing B12-deficient growth medium with AsA-2G rescued the paralysis phenotype. However, AsA-2G had no effect on the aggregation of Aß peptides. Our results indicated that B12 supplementation lowered Hcy levels and alleviated Aß toxicity, suggesting that oxidative stress caused by elevated Hcy levels is an important factor in Aß toxicity.

17.
PLoS One ; 16(3): e0248999, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33750977

RESUMO

BACKGROUND: Delayed identification of infiltration and dysfunction of peripheral intravenous (PIV) access can lead to serious consequences during general anesthesia in children. This preliminary study aimed to describe the application of precordial Doppler ultrasound during general anesthesia in children to detect and confirm the correct PIV access and to evaluate the accuracy of this method. METHODS: This was a single-center, preliminary study that was conducted in children (<18 years) who were scheduled for elective surgeries between October 2019 and March 2020. Rater anesthesiologists judged the change in precordial Doppler sound (S test) before and after injection of 0.5 mL/kg of normal saline (NS) via PIV. Blood flow velocity before and after NS injection was recorded, and multiple cutoff points were set to analyze the accuracy of detecting the infiltration and dysfunction of PIV catheter (V test). RESULTS: The total incidence of peripheral infiltration and dysfunction of PIV catheter was 7/512 (1.4%). In the S test, the sensitivity, specificity, positive and negative likelihood ratios, and area under the receiver-operating characteristic curves (AUCs) were 5/7 (71.4%; 95% confidence interval [CI], 29.0%-96.3%), 490/505 (97.0%; 95% CI, 95.1%-98.3%), 24.0, 0.29, and 0.84, respectively. The V test showed that the reasonable threshold of blood flow velocity change was 1.0 m/s, with sensitivity, specificity, positive and negative likelihood ratios, and AUC of 4/7 (57.1%; 95% CI, 18.4%-90.1%), 489/505 (96.8%; 95% CI, 94.9%-98.2%), 18.0 and 0.44, and 0.84, respectively. CONCLUSIONS: This preliminary study demonstrated that precordial Doppler ultrasound is a feasible, easy-to-use, and noninvasive technique with good accuracy to confirm the correct PIV access during general anesthesia in children. However, its accuracy requires further evaluation.


Assuntos
Anestesia Geral , Ultrassonografia Doppler , Veias/fisiologia , Administração Intravenosa , Velocidade do Fluxo Sanguíneo , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/fisiopatologia , Humanos , Lactente , Masculino , Curva ROC , Fluxo Sanguíneo Regional/fisiologia
18.
Pediatr Int ; 63(11): 1289-1296, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33657683

RESUMO

BACKGROUND: Aortic valve neo-cuspidization (AVNeo), a procedure wherein the aortic valve is reconstructed utilizing an autologous pericardium, has recently been more commonly performed in children. However, the postoperative morphological changes in the aortic valve of pediatric patients remain unknown. The current study aimed to describe the intraoperative and postoperative findings of aortic regurgitation (AR) and stenosis (AS) after AVNeo in children. METHODS: This case series describes the morphological changes in AR and AS, and their severity, between the perioperative period and 3 months postoperative period after AVNeo in children (<18 years) who underwent AVNeo between April 2016 and March 2020. Data were collected at two measurement points: (i) intraoperative transesophageal echocardiography after weaning from cardiopulmonary bypass (io-TEE); (ii) postoperative transthoracic echocardiography 3 months after the procedure (po-TTE). RESULTS: Seven patients were included in this case series. The number of postoperative AR sites and the ratio of AR jet area to the left ventricular outflow tract area showed a tendency to decrease between io-TEE and po-TTE. All AR sites were integrated during the postoperative period. One patient identified developed intraoperative AS, which maintained its severity after AVNeo. CONCLUSIONS: Most cases exhibited spontaneous improvement in AR, while one developed postoperative AS. Further prospective investigation is, therefore, needed to explore surgical outcomes following AVNeo among children.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia , Criança , Ecocardiografia , Ecocardiografia Transesofagiana , Humanos , Pericárdio
19.
Food Chem ; 347: 129048, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33493835

RESUMO

In this study, we determined the vitamin B12 content of commercially-available edible insect products using a bioassay based on Lactobacillus delbrueckii ATCC 7830. Although the vitamin content of giant water bug, bee larva, grasshopper, and weaver ant products was low, we found that diving beetle and cricket products contained relatively high amounts of vitamin B12 (approximately 89.5 and 65.8 µg/100 g dry weight, respectively). In the cricket products most widely circulated as foods, specific corrinoid (vitamin B12) compounds were extracted and identified using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Despite the bioassay detecting high vitamin B12 content (approximately 50-75 µg/100 g dry weight) in these cricket products, UPLC-MS/MS analysis indicated that pseudovitamin B12 and 2-methylmercaptoadenyl cobamide (also known as factor S) were actually the predominant corrinoid compounds (~74% and ~21%, respectively), with authentic vitamin B12 making up only 5% of total corrinoids.


Assuntos
Corrinoides/análise , Análise de Alimentos/métodos , Gryllidae/metabolismo , Vitamina B 12/análise , Animais , Cromatografia Líquida de Alta Pressão , Gryllidae/química , Espectrometria de Massas em Tandem
20.
Redox Biol ; 37: 101724, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32961438

RESUMO

Using Caenorhabditis elegans as a model animal, we evaluated the effects of chronical supplementation with high-dose folic acid on physiological events such as life cycle and egg-laying capacity and folate metabolism. Supplementation of high-dose folic acid significantly reduced egg-laying capacity. The treated worms contained a substantial amount of unmetabolized folic acid and exhibited a significant downregulation of the mRNAs of cobalamin-dependent methionine synthase reductase and 5,10-methylenetetrahydrofolate reductase. In vitro experiments showed that folic acid significantly inhibited the activity of cobalamin-dependent methionine synthase involved in the metabolism of both folate and methionine. In turn, these metabolic disorders induced the accumulation of unmetabolized homocysteine, leading to severe oxidative stress in worms. These results were similar to the phenomena observed in mammals during folate deficiency.


Assuntos
Caenorhabditis elegans , Homocisteína , Animais , Suplementos Nutricionais , Ácido Fólico , Estresse Oxidativo
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