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1.
Vopr Pitan ; 93(1): 92-102, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38555613

RESUMO

The influence of a stress factor, widespread in modern conditions, on the vitamin status has not been studied enough. At the same time, the negative stress impact can be aggravated against the background of unhealthy nutrition, which in turn affects the vitamin status of the organism. In this regard, the goal of the research was to evaluate the effect of chronic restrict stress on the vitamin supply in rats fed a diet with adequate and increased content of fat, sugar and cholesterol. Material and methods. The experiment was carried out on 37 growing male Wistar rats (initial body weight of 45±5 g) divided into 4 groups. Animals of the 1st (control) and the 2nd groups received a complete semi-synthetic diet (CSSD) (20% protein, 10% fat, 58% carbohydrates in the form of starch, 384 kcal/100 g) for 92 days. The levels of all vitamins and mineral elements in the rats' diets were adequate for growing rats. Rats of the 3rd and the 4th groups were fed a high-calorie, high-fat high-carbohydrate diet (HFHCD) (20% protein, 28% fat, 2% cholesterol, 18% carbohydrates in the form of starch, 20% sucrose, 511 kcal/100 g). Animals of groups 2 and 4 were subjected to daily 90-minute immobilization. The concentration of vitamins A (retinol and retinol palmitate) and E (α-tocopherol) in the blood serum and liver were determined by high-performance liquid chromatography, vitamins B1 and B2 in the liver and urine, as well as riboflavin in the blood serum and 4-pyridoxic acid (4-PA) in urine were determined by fluorimetric methods. Biochemical parameters of blood serum were determined on a biochemical analyzer; the total content of fat, triglycerides (TG) and cholesterol (CH) was determined in the liver. Results. Replacing CSSD with HFHCD, both under restraint stress and without, was accompanied by an increase in liver weight by 1.8-2.0 fold, in its fat content by 2.6-3.3 fold, cholesterol by 32.6-35.3 fold and TG - by 33.0-57.6 fold (p=<0.001). An increase in alanine aminotransferase (ALT) activity by 1.7-2.0 fold (p=<0.01), in low-density lipoprotein (LDL) cholesterol level by 5.4 fold (p=<0.05) and the atherogenic coefficient by 2.5 fold (p<0.01) as well as a decrease in creatinine and urea level (p=<0.05) in blood serum were revealed. Immobilization was accompanied by a decrease in body weight, liver and liver fat in rats fed both CSSD and HFHCD (p<0.05), but didn't affect the blood serum biochemical parameters, with the exception of an increase in ALT activity. If the activity of alkaline phosphatase (ALP) did not change during immobilization of rats fed the CSSD, then in animals fed the high-calorie diet it decreased by 37.5% (p=<0.05 from the control) under its increase against the background of restrict stress by 78.7% (p=<0.01) compared to the indicator of rats of the 3rd group. Immobilization of rats treated with CSSD was accompanied by an increase in both absolute serum α-tocopherol level and concentration correlated with the level of cholesterol and triglycerides by 26.0-57.5% (p<0.05), with a simultaneous decrease in its content in the liver per 1 g of wet tissue by 22.1% (p=0.041) relative to the indicators of intact animals. Immobilization reduced the level of retinol palmitate in the liver by 2.3 times (p<0.01), but did not affect retinol level in the blood serum. At the same time, indicators of B vitamin status (the content of vitamins B1 and B2 in the liver per 1 g of wet tissue and per organ, blood serum riboflavin level, urinary excretion of riboflavin and 4-PA) did not change, with the exception of thiamine urinary excretion, which reduced compared to the control by 38.8%. In rats fed HFHCD, immobilization had no additional effect on the supply with vitamins A and E. The content of vitamins B1 and B2 in the liver in terms of the whole organ was reduced by 14.0-26.7% relative to the indicator in animals of the 3rd group, not subjected to chronic stress, only due to differences in liver weight in animals of these groups. Conclusion. The data obtained indicate that chronic stress has a negative effect on the vitamin status of the body, worsening the supply with vitamins A, E and B1, and substantiate the feasibility of studying the mechanisms of this effect in order to develop effective vitamin complexes for the treatment and prevention of diseases caused by long-term stress.


Assuntos
Diterpenos , Ésteres de Retinil , Vitamina A , Complexo Vitamínico B , Ratos , Masculino , Animais , alfa-Tocoferol , Ratos Wistar , Tiamina , Riboflavina , Complexo Vitamínico B/metabolismo , Triglicerídeos/metabolismo , Fígado/metabolismo , Vitamina K/metabolismo , Dieta , Colesterol , Carboidratos , Peso Corporal , Amido/metabolismo
2.
Clin Transl Sci ; 17(1): e13710, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38226444

RESUMO

To improve outcomes in fetuses with spina bifida (SB), better understanding is needed of the molecular drivers of SB and its comorbidities. Pregnant people carrying a fetus with isolated SB (cases; n = 12) or a fetus with no congenital anomalies (controls; n = 21) were recruited at Mount Sinai Hospital, Toronto, Ontario, Canada. Clinical data and placental samples were collected. Placental transcriptome was sequenced (Clariom D microarray) and a nutrient-focused gene expression analysis pipeline was applied to determine whether fetal SB associates with placental dysfunction. Of the 391 differentially expressed genes (DEGs) in cases, 11% (n = 42) had at least one nutrient cofactor, including B vitamins (n = 7 genes), iron/heme (n = 6), and zinc (n = 11). Cases had dysregulation in genes not previously known to associate with SB, and in placental genes that have known links to SB but have not been previously identified in the placenta. Cases also had downregulated nutrient transport and upregulated branching angiogenesis and immune/inflammatory processes. Five nutrient-dependent transcription regulators, collectively predicted to target 46% of DEGs in cases, were identified and were most commonly dependent on B vitamins (n = 3) and zinc (n = 2). Placental gene expression changes were most acute in cases with poor growth. Placentae from fetuses with SB have dysregulation in several gene networks, including those that are sensitive to multiple micronutrients beyond the well-known folic acid. An improved understanding of placental phenotype in fetuses with SB may help identify novel mechanisms associated with comorbidities in fetuses with SB, and reveal new targets to improve fetal outcomes in this population.


Assuntos
Disrafismo Espinal , Complexo Vitamínico B , Humanos , Gravidez , Feminino , Placenta , Estudos de Casos e Controles , Complexo Vitamínico B/metabolismo , Redes Reguladoras de Genes , Disrafismo Espinal/epidemiologia , Disrafismo Espinal/genética , Disrafismo Espinal/metabolismo , Nutrientes , Zinco/metabolismo
3.
Nutrients ; 15(11)2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37299487

RESUMO

B vitamins as a group play essential roles in a multitude of metabolic reactions involved in cellular replication, energy production, the synthesis of intermediary compounds, and neurotransmitters [...].


Assuntos
Complexo Vitamínico B , Complexo Vitamínico B/metabolismo , Ácido Fólico/metabolismo , Encéfalo/metabolismo , Vitamina B 12/metabolismo
4.
Animal ; 17 Suppl 3: 100834, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37210233

RESUMO

Synthesis of B vitamins by the rumen microbiota is usually sufficient to avoid the appearance of clinical deficiency symptoms in dairy cows under normal feeding conditions. Nevertheless, it is now generally accepted that vitamin deficiency is much more than the appearance of major functional and morphological symptoms. Subclinical deficiency, which is present as soon as the supply is lower than the need, causes cellular metabolic changes leading to a loss of metabolic efficiency. Folates and cobalamin, two B vitamins, share close metabolic relationships. Folates act as co-substrates in one-carbon metabolism, providing one-carbon unit for DNA synthesis and de novo synthesis of methyl groups for the methylation cycle. Cobalamin acts as a coenzyme for reactions in the metabolism of amino acids, odd-numbered chain fatty acids including propionate and de novo synthesis of methyl groups. Both vitamins are involved in reactions to support lipid and protein metabolism, nucleotide synthesis, methylation reactions and possibly, maintenance of redox status. Over the last decades, several studies have reported the beneficial effects of folic acid and vitamin B12 supplements on lactation performance of dairy cows. These observations indicate that, even when cows are fed diets adequately balanced for energy and major nutrients, B-vitamin subclinical deficiency could be present. This condition reduces casein synthesis in the mammary gland and milk and milk component yields. Folic acid and vitamin B12 supplements, especially when given together, may alter energy partitioning in dairy cows during early and mid-lactation as indicated by increased milk, energy-corrected milk, or milk component yields without affecting DM intake and BW or even with reductions in BW or body condition loss. Folate and cobalamin subclinical deficiency interferes with efficiency of gluconeogenesis and fatty acid oxidation and possibly alters responses to oxidative conditions. The present review aims to describe the metabolic pathways affected by folate and cobalamin supply and the consequences of a suboptimal supply on metabolic efficiency. The state of knowledge on the estimation of folate and cobalamin supply is also briefly mentioned.


Assuntos
Vitamina B 12 , Complexo Vitamínico B , Feminino , Bovinos , Animais , Vitamina B 12/análise , Complexo Vitamínico B/análise , Complexo Vitamínico B/metabolismo , Ácido Fólico , Suplementos Nutricionais , Dieta/veterinária , Lactação/fisiologia , Leite/química , Rúmen/metabolismo
5.
Nutrients ; 15(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36839219

RESUMO

BACKGROUND: Increasingly, chronic kidney disease (CKD) is becoming an inevitable consequence of obesity, metabolic syndrome, and diabetes. As the disease progresses, and through dialysis, the need for and loss of water-soluble vitamins both increase. This review article looks at the benefits and possible risks of supplementing these vitamins with the treatment of CKD. METHODS: Data in the PubMed and Embase databases were analyzed. The keywords "chronic kidney disease", in various combinations, are associated with thiamin, riboflavin, pyridoxine, pantothenic acid, folates, niacin, cobalamin, and vitamin C. This review focuses on the possible use of water-soluble vitamin supplementation to improve pharmacological responses and the overall clinical condition of patients. RESULTS: The mechanism of supportive supplementation is based on reducing oxidative stress, covering the increased demand and losses resulting from the treatment method. In the initial period of failure (G2-G3a), it does not require intervention, but later, especially in the case of inadequate nutrition, the inclusion of supplementation with folate and cobalamin may bring benefits. Such supplementation seems to be a necessity in patients with stage G4 or G5 (uremia). Conversely, the inclusion of additional B6 supplementation to reduce CV risk may be considered. At stage 3b and beyond (stages 4-5), the inclusion of niacin at a dose of 400-1000 mg, depending on the patient's tolerance, is required to lower the phosphate level. The inclusion of supplementation with thiamine and other water-soluble vitamins, especially in peritoneal dialysis and hemodialysis patients, is necessary for reducing dialysis losses. Allowing hemodialysis patients to take low doses of oral vitamin C effectively reduces erythropoietin dose requirements and improves anemia in functional iron-deficient patients. However, it should be considered that doses of B vitamins that are several times higher than the recommended dietary allowance of consumption may exacerbate left ventricular diastolic dysfunction in CKD patients. CONCLUSIONS: Taking into account the research conducted so far, it seems that the use of vitamin supplementation in CKD patients may have a positive impact on the treatment process and maintaining a disease-free condition.


Assuntos
Falência Renal Crônica , Niacina , Insuficiência Renal Crônica , Complexo Vitamínico B , Humanos , Diálise Renal , Complexo Vitamínico B/metabolismo , Tiamina , Ácido Ascórbico , Ácido Fólico , Vitamina B 12 , Falência Renal Crônica/terapia , Suplementos Nutricionais , Água
6.
J Cell Biol ; 221(12)2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36374222

RESUMO

MR1 is a conserved molecule that binds microbial vitamin B metabolites and presents them to unconventional T cells. Lim and colleagues (2022. J. Cell Biol.https://doi.org/10.1083/jcb.202110125) uncover the role of AP2 in ensuring MR1 surface presentation, which relies on an atypical motif within the MR1 cytoplasmic tail.


Assuntos
Complexo 2 de Proteínas Adaptadoras , Apresentação de Antígeno , Antígenos de Histocompatibilidade Classe I , Antígenos de Histocompatibilidade Menor , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Linfócitos T , Humanos , Complexo Vitamínico B/metabolismo , Complexo 2 de Proteínas Adaptadoras/metabolismo
7.
ISME J ; 16(12): 2712-2724, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35987782

RESUMO

Auxotrophs are unable to synthesize all the metabolites essential for their metabolism and rely on others to provide them. They have been intensively studied in laboratory-generated and -evolved mutants, but emergent adaptation mechanisms to auxotrophy have not been systematically addressed. Here, we investigated auxotrophies in bacteria isolated from Arabidopsis thaliana leaves and found that up to half of the strains have auxotrophic requirements for biotin, niacin, pantothenate and/or thiamine. We then explored the genetic basis of auxotrophy as well as traits that co-occurred with vitamin auxotrophy. We found that auxotrophic strains generally stored coenzymes with the capacity to grow exponentially for 1-3 doublings without vitamin supplementation; however, the highest observed storage was for biotin, which allowed for 9 doublings in one strain. In co-culture experiments, we demonstrated vitamin supply to auxotrophs, and found that auxotrophic strains maintained higher species richness than prototrophs upon external supplementation with vitamins. Extension of a consumer-resource model predicted that auxotrophs can utilize carbon compounds provided by other organisms, suggesting that auxotrophic strains benefit from metabolic by-products beyond vitamins.


Assuntos
Biotina , Complexo Vitamínico B , Biotina/metabolismo , Complexo Vitamínico B/metabolismo , Tiamina/metabolismo , Vitamina A , Folhas de Planta/metabolismo , Vitamina K , Bactérias/metabolismo
8.
FEMS Yeast Res ; 22(1)2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36007922

RESUMO

Nonalcoholic beers are becoming increasingly popular, in part due to consumers' awareness of a healthier lifestyle. Additionally, consumers are demanding diversification in the product range, which can be offered by producing nonalcoholic beers using non-Saccharomyces yeasts for fermentation to create a wide variety of flavors. So far, little is known about the nutritionally relevant byproducts that these yeasts release during wort fermentation and whether these yeasts can be considered safe for food fermentations. To gain insights into this, the B vitamins of four different nonalcoholic beers fermented with the yeast species Saccharomycodes ludwigii, Cyberlindnera saturnus (two strains), and Kluyveromyces marxianus were analyzed. Furthermore, a total of 16 beers fermented with different non-Saccharomyces yeast strains were analyzed for biogenic amines. Additionally, stress tolerance tests were performed at 37°C and in synthetic human gastric juice in vitro. B vitamins were found in the four nonalcoholic beers in nutritionally relevant amounts so they could serve as a supplement for a balanced diet. Biogenic amines remained below the limit of determination in all 16 beers, and thus likely had no influence, while the stress tolerance tests gave a first indication that seven yeast strains could possibly tolerate the human gastric juice milieu.


Assuntos
Cerveja , Complexo Vitamínico B , Humanos , Cerveja/análise , Complexo Vitamínico B/metabolismo , Leveduras/metabolismo , Fermentação
9.
J Dairy Sci ; 105(9): 7399-7415, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35879170

RESUMO

As milk production has significantly increased over the past decade(s), existing estimates of the B-vitamin needs of the modern dairy cow are currently being reconsidered, as suboptimal B-vitamin supply may affect metabolic efficiency. At the same time, however, "true" (i.e., biologically active forms, excluding nonfunctional analogs) B-vitamin supply also cannot be adequately estimated by dietary intake, as the rumen microbiota has been shown to play a significant role in synthesis and utilization of B vitamins. Given their complex impact on the metabolism of dairy cows, incorporating these key nutrients into the next generation of mathematical models could help to better predict animal production and performance. Therefore, the purpose of this study was to generate hypotheses of regulation in the absence of supplemental B vitamins by creating empirical models, through a meta-analysis, to describe true B-vitamin supply to the cow (postruminal flow, PRF) and apparent ruminal synthesis (ARS). The database used for this meta-analysis consisted of 340 individual cow observations from 15 studies with 16 experiments, where diet and postruminal digesta samples were (post hoc) analyzed for content of B vitamins (B1, B2, B3, B6, B9, B12). Equations of univariate and multivariate linear form were considered. Models describing ARS considered dry matter intake (DMI, kg/d), B-vitamin dietary concentration [mg/kg of dry matter (DM)] and rumen-level variables such as rumen digestible neutral detergent fiber (NDF) and starch (g/kg of DM), total volatile fatty acids (VFA, mM), acetate, propionate, butyrate, and valerate molar proportions (% of VFA), mean pH, and fractional rates of degradation of NDF and starch (%/h). Models describing PRF considered dietary-level driving variables such as DMI, B-vitamin dietary concentration (mg/kg of DM), starch and crude protein (g/kg of DM) and forage NDF (g/kg of DM). Equations developed were required to contain all significant slope parameters and contained no significant collinearity between driving variables. Concordance correlation coefficient was used to evaluate the models on the developmental data set due to data scarcity. Overall, modeling ARS yielded better-performing models compared with modeling PRF, and DMI was included in all prediction equations as a scalar variable. The B-vitamin dietary concentration had a negative effect on the ARS of B1, B2, B3, and B6 but increased the PRF of B2 and B9. The rumen digestible NDF concentration had a negative effect on the ARS of B2, B3, and B6, whereas rumen digestible starch concentration had a negative effect on the ARS of B1 and a positive effect on the ARS of B9. In the best prediction models, the dietary starch increased PRF of B1, B2, and B9 but decreased PRF of B12. The equations developed may be used to better understand the effect of diet and ruminal environment on the true supply of B vitamins to the dairy cow and stimulate the development of better-defined requirements in the future.


Assuntos
Complexo Vitamínico B , Animais , Bovinos , Dieta/veterinária , Fibras na Dieta/metabolismo , Digestão , Feminino , Fermentação , Lactação/fisiologia , Leite/química , Rúmen/metabolismo , Amido/metabolismo , Complexo Vitamínico B/metabolismo
10.
Plant J ; 111(3): 662-682, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35673947

RESUMO

B vitamins are a group of water-soluble micronutrients that are required in all life forms. With the lack of biosynthetic pathways, humans depend on dietary uptake of these compounds, either directly or indirectly, from plant sources. B vitamins are frequently given little consideration beyond their role as enzyme accessory factors and are assumed not to limit metabolism. However, it should be recognized that each individual B vitamin is a family of compounds (vitamers), the regulation of which has dedicated pathways. Moreover, it is becoming increasingly evident that individual family members have physiological relevance and should not be sidelined. Here, we elaborate on the known forms of vitamins B1 , B6 and B9 , their distinct functions and importance to metabolism, in both human and plant health, and highlight the relevance of vitamer homeostasis. Research on B vitamin metabolism over the past several years indicates that not only the total level of vitamins but also the oft-neglected homeostasis of the various vitamers of each B vitamin is essential to human and plant health. We briefly discuss the potential of plant biology studies in supporting human health regarding these B vitamins as essential micronutrients. Based on the findings of the past few years we conclude that research should focus on the significance of vitamer homeostasis - at the organ, tissue and subcellular levels - which could improve the health of not only humans but also plants, benefiting from cross-disciplinary approaches and novel technologies.


Assuntos
Complexo Vitamínico B , Vias Biossintéticas , Homeostase , Humanos , Micronutrientes , Plantas/metabolismo , Complexo Vitamínico B/metabolismo
11.
Environ Microbiol ; 24(9): 4049-4064, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35191580

RESUMO

The symbiotic association between bacterial symbionts and insect hosts is a complicated process that is not completely understood. Herein, we used a silkworm model to study the association between symbiotic Bacillus and lepidopteran insect by investigating the changes in intestinal microbiota and hemolymph circulating metabolites of silkworm after symbiotic Bacillus subtilis treatment. Results showed that B. subtilis can generate a variety of primary and secondary metabolites, such as B vitamins and antimicrobial compounds, to provide micronutrients and enhance the pathogen resistance of their insect host. Shifts in the relative abundance of Enterococcus, Brevibacterium, Buttiauxella, Pseudomonas, Brevundimonas and Limnobacter had significant correlations with the concentrations of differential metabolites (e.g. phospholipids and certain amino acids) in insect hemolymph. The antimicrobial compounds secreted by B. subtilis were the primary driving force for the reconstruction of intestinal microbiota. Meanwhile, the altered levels of circulating metabolites in multiple metabolic pathways were potential adaptive mechanism of insect hosts in response to the shifts of intestinal microbiota. Our findings provided concrete evidence that bacterial intestinal symbiont can alter the physiological state of insects and highlighted the importance of the compositional alterations of intestinal microbiota as a source of variation in circulating metabolites of insect hosts.


Assuntos
Bacillus , Microbioma Gastrointestinal , Complexo Vitamínico B , Aminoácidos/metabolismo , Animais , Antibacterianos/metabolismo , Bactérias/metabolismo , Insetos/microbiologia , Simbiose/fisiologia , Complexo Vitamínico B/metabolismo
12.
Curr Opin Plant Biol ; 66: 102170, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35063913

RESUMO

In plants, primary and specialized metabolism have classically been distinguished as either essential for growth or required for survival in a particular environment. Coenzymes (organic cofactors) are essential for growth but their importance to specialized metabolism is often not considered. In line with the recent proposal of viewing primary and specialized metabolism as an integrated whole rather than segregated lots with a defined interface, we highlight here the importance of collating information on the regulation of coenzyme supply with metabolic demands using examples of vitamin B derived coenzymes. We emphasize that coenzymes can have enormous influence on the outcome of metabolic as well as engineered pathways and should be taken into account in the era of synthetic biology.


Assuntos
Coenzimas , Complexo Vitamínico B , Coenzimas/metabolismo , Plantas/genética , Plantas/metabolismo , Complexo Vitamínico B/metabolismo
13.
CNS Neurol Disord Drug Targets ; 21(4): 292-301, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34477538

RESUMO

BACKGROUND: Regulation of glutamate release is crucial for maintaining normal brain function, but excess glutamate release is implicated in many neuropathological conditions. Therefore, the minimum glutamate release from presynaptic nerve terminals is an important neuroprotective mechanism. OBJECTIVE: In this mini-review, we analyze the three B vitamins, namely vitamin B2 (riboflavin), vitamin B6 (pyridoxine), and vitamin B12 (cyanocobalamin), that affect the 4-aminopyridine (4- AP)-evoked glutamate release from presynaptic nerve terminal in rat and discuss their neuroprotective role. METHODS: In this study, the measurements include glutamate release, DiSC3(5), and Fura-2. RESULTS: The riboflavin, pyridoxine, and cyanocobalamin produced significant inhibitory effects on 4-aminopyridine-evoked glutamate release from rat cerebrocortical nerve terminals (synaptosomes) in a dose-dependent relationship. These presynaptic inhibitory actions of glutamate release are attributed to inhibition of physiologic Ca2+-dependent vesicular exocytosis but not Ca2+-independent nonvesicular release. These effects also did not affect membrane excitability, while diminished cytosolic (Ca2+)c through a reduction of direct Ca2+ influx via Cav2.2 (N-type) and Cav2.1 (P/Q-type) Ca2+ channels, rather than through indirect Ca2+induced Ca2+ release from ryanodine-sensitive intracellular stores. Furthermore, their effects were attenuated by GF109203X and Ro318220, two protein kinase C (PKC) inhibitors, suggesting suppression of PKC activity. Taken together, these results suggest that riboflavin, pyridoxine, and cyanocobalamin inhibit presynaptic vesicular glutamate release from rat cerebrocortical synaptosomes, through the depression Ca2+ influx via voltage- dependent Cav2.2 (N-type) and Cav2.1 (P/Q-type) Ca2+ channels, and PKC signaling cascade. CONCLUSION: Therefore, these B vitamins may reduce the strength of glutamatergic synaptic transmission and is of considerable importance as potential targets for therapeutic agents in glutamate- induced excitation-related diseases.


Assuntos
Ácido Glutâmico/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Complexo Vitamínico B/metabolismo , 4-Aminopiridina , Animais , Cálcio/metabolismo , Canais de Cálcio Tipo N , Córtex Cerebral/metabolismo , Masculino , Potenciais da Membrana/efeitos dos fármacos , Terminações Pré-Sinápticas/efeitos dos fármacos , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Sinaptossomos/efeitos dos fármacos
14.
Appl Environ Microbiol ; 88(3): e0208921, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-34818107

RESUMO

Nutritional symbionts are restricted to specialized host cells called bacteriocytes in various insect orders. These symbionts can provide essential nutrients to the host. However, the cellular mechanisms underlying the regulation of these insect-symbiont metabolic associations remain largely unclear. The whitefly Bemisia tabaci MEAM1 hosts "Candidatus Portiera aleyrodidarum" (here, "Ca. Portiera") and "Candidatus Hamiltonella defensa" (here, "Ca. Hamiltonella") bacteria in the same bacteriocyte. In this study, the induction of autophagy by chemical treatment and gene silencing decreased symbiont titers and essential amino acid (EAA) and B vitamin contents. In contrast, the repression of autophagy in bacteriocytes via Atg8 silencing increased symbiont titers, and amino acid and B vitamin contents. Furthermore, dietary supplementation with non-EAAs or B vitamins alleviated autophagy in whitefly bacteriocytes, elevated TOR (target of rapamycin) expression, and increased symbiont titers. TOR silencing restored symbiont titers in whiteflies after dietary supplementation with B vitamins. These data suggest that "Ca. Portiera" and "Ca. Hamiltonella" evade autophagy of the whitefly bacteriocytes by activating the TOR pathway via providing essential nutrients. Taken together, we demonstrate that autophagy plays a critical role in regulating the metabolic interactions between the whitefly and two intracellular symbionts. Therefore, this study reveals that autophagy is an important cellular basis for bacteriocyte evolution and symbiosis persistence in whiteflies. The whitefly symbiosis unravels the interactions between cellular and metabolic functions of bacteriocytes. IMPORTANCE Nutritional symbionts, which are restricted to specialized host cells called bacteriocytes, can provide essential nutrients for many hosts. However, the cellular mechanisms of regulation of animal-symbiont metabolic associations have been largely unexplored. Here, using the whitefly-"Ca. Portiera"/"Ca. Hamiltonella" endosymbiosis, we demonstrate autophagy regulates the symbiont titers and thereby alters the essential amino acid and B vitamin contents. For persistence in the whitefly bacteriocytes, "Ca. Portiera" and "Ca. Hamiltonella" alleviate autophagy by activating the TOR (target of rapamycin) pathway through providing essential nutrients. Therefore, we demonstrate that autophagy plays a critical role in regulating the metabolic interactions between the whitefly and two intracellular symbionts. This study also provides insight into the cellular basis of bacteriocyte evolution and symbiosis persistence in the whitefly. The mechanisms underlying the role of autophagy in whitefly symbiosis could be widespread in many insect nutritional symbioses. These findings provide a new avenue for whitefly control via regulating autophagy in the future.


Assuntos
Halomonadaceae , Hemípteros , Complexo Vitamínico B , Animais , Autofagia , Halomonadaceae/genética , Hemípteros/microbiologia , Simbiose/genética , Complexo Vitamínico B/metabolismo
15.
Cell Rep ; 37(13): 110164, 2021 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-34965410

RESUMO

The functional and genomic diversity of the human gut microbiome is shaped by horizontal transfer of mobile genetic elements (MGEs). Characterized MGEs can encode genes beneficial for their host's self-defense (e.g., antibiotic resistance) or ability to compete for essential or limited resources (e.g., vitamins). Vitamin B12 and related compounds (corrinoids) are critical nutrients that enable colonization by members of the common gut microbe phylum, the Bacteroidetes. Herein, we identify a distinct class of MGEs in the Bacteroidetes responsible for the mobilization and exchange of the genes required for transport of corrinoids, a group of cyclic tetrapyrrole cofactors including vitamin B12 (btuGBFCD). This class includes two distinct groups of conjugative transposons (CTns) and one group of phage. Conjugative transfer and vitamin B12 transport activity of two of the CTns were confirmed in vitro and in vivo, demonstrating the important role MGEs play in distribution of corrinoid transporters in the Bacteroidetes.


Assuntos
Proteínas de Bactérias/metabolismo , Bacteroidetes/metabolismo , Corrinoides/metabolismo , Microbioma Gastrointestinal , Sequências Repetitivas Dispersas , Proteínas de Membrana Transportadoras/metabolismo , Vitamina B 12/metabolismo , Animais , Proteínas de Bactérias/genética , Bacteroidetes/crescimento & desenvolvimento , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Complexo Vitamínico B/metabolismo
16.
Molecules ; 26(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34641607

RESUMO

The application of bacterial cultures in food fermentation is a novel strategy to increase the "natural" levels of bioactive compounds. The unique ability of lactic acid bacteria (LAB) to produce folate, B vitamins, and conjugated linolenic acid cis9trans11 C18:2 (CLA) during cold storage up to 21 days was studied. Although some species of LAB can produce folates and other important nutrients, little is known about the production ability of yogurt starter cultures. Pasteurized milk samples were inoculated with four different combinations of commercially available yogurt vaccines, including starter cultures of Bifidobacterium bifidum. Both the type of vaccine and the time of storage at 8 °C had a significant effect on the folate and CLA contents in the tested fermented milks. The highest folate content (105.4 µg/kg) was found in fresh fermented milk inoculated with Lactobacillus delbrueckii, Streptococcus thermophilus, and Bifidobacterium bifidum. Only the mix of Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and Bifidobacterium bifidum showed potential (59% increase) to synthesize folate during seven days of storage. A significant increase in the content of CLA, when compared to fresh fermented milk, was observed during cold storage for up to 21 days in products enriched with Bifidobacterium bifidum.


Assuntos
Produtos Fermentados do Leite/microbiologia , Ácido Fólico/metabolismo , Lactobacillales/metabolismo , Ácidos Linoleicos Conjugados/metabolismo , Leite/metabolismo , Leite/microbiologia , Complexo Vitamínico B/metabolismo , Animais , Bifidobacterium bifidum/metabolismo , Biofortificação/métodos , Fermentação , Microbiologia de Alimentos , Lactobacillus delbrueckii/metabolismo , Probióticos , Streptococcus thermophilus/metabolismo , Fatores de Tempo
17.
Epilepsia ; 62(12): 2968-2980, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34590314

RESUMO

OBJECTIVE: Antiseizure medication (ASM) use interacts with vitamin B status in nonpregnant epilepsy populations. We aimed to examine the association between ASM and vitamin B status in pregnant women with epilepsy. METHODS: We performed a cross-sectional study of pregnancies in women with epilepsy enrolled in the Norwegian Mother, Father and Child Cohort Study from 1999 to 2008. Data on ASM and vitamin supplement use were collected from questionnaires. We analyzed maternal plasma concentrations of ASM and metabolites of folate, including unmetabolized folic acid (UMFA), riboflavin (vitamin B2), pyridoxine (vitamin B6), and niacin (vitamin B3) during gestational weeks 17-19. RESULTS: We included 227 singleton pregnancies exposed to ASM with available plasma samples (median maternal age 29 years, range 18 to 41 years). From the preconception period to gestational week 20, any supplement of folic acid was reported in 208 of pregnancies (94%), riboflavin in 72 (33%), pyridoxine in 77 (35%), and niacin in 45 (20%). High ASM concentrations correlated with high concentrations of UMFA and inactive folate metabolites, and with low concentrations of riboflavin and metabolically active pyridoxine. There was no association between ASM and niacin status. SIGNIFICANCE: ASM concentrations during pregnancy were associated with vitamin B status in pregnant women with epilepsy. Additional studies are needed to determine the clinical impact of these findings, and to define the optimal vitamin doses that should be recommended to improve pregnancy outcomes.


Assuntos
Epilepsia , Niacina , Complexo Vitamínico B , Adolescente , Adulto , Criança , Estudos de Coortes , Estudos Transversais , Epilepsia/tratamento farmacológico , Feminino , Ácido Fólico/uso terapêutico , Humanos , Niacina/uso terapêutico , Gravidez , Gestantes , Piridoxina/uso terapêutico , Riboflavina/uso terapêutico , Complexo Vitamínico B/metabolismo , Complexo Vitamínico B/uso terapêutico , Adulto Jovem
18.
ACS Synth Biol ; 10(9): 2286-2307, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34470212

RESUMO

Yeast is a dominant host for recombinant production of heterologous proteins, high-value biochemical compounds, and microbial fermentation. During bioprocess operations, pH fluctuations, organic solvents, drying, starvation, osmotic pressure, and often a combination of these stresses cause growth inhibition or death, markedly limiting its industrial use. Thus, stress-tolerant yeast strains with balanced energy-bioenergetics are highly desirous for sustainable improvement of quality biotechnological production. We isolated two NAC transcription factors (TFs), VuNAC1 and VuNAC2, from a wild cowpea genotype, improving both stress tolerance and growth when expressed in yeast. The GFP-fused proteins were localized to the nucleus. Y2H and reporter assay demonstrated the dimerization and transactivation abilities of the VuNAC proteins having structural folds similar to rice SNAC1. The gel-shift assay indicated that the TFs recognize an "ATGCGTG" motif for DNA-binding shared by several native TFs in yeast. The heterologous expression of VuNAC1/2 in yeast improved growth, biomass, lifespan, fermentation efficiency, and altered cellular composition of biomolecules. The transgenic strains conferred tolerance to multiple stresses such as high salinity, osmotic stress, freezing, and aluminum toxicity. Analysis of the metabolome revealed reprogramming of major pathways synthesizing nucleotides, vitamin B complex, amino acids, antioxidants, flavonoids, and other energy currencies and cofactors. Consequently, the transcriptional tuning of stress signaling and biomolecule metabolism improved the survival of the transgenic strains during starvation and stress recovery. VuNAC1/2-based synthetic gene expression control may contribute to designing robust industrial yeast strains with value-added productivity.


Assuntos
Metabolismo Energético/fisiologia , Proteínas de Plantas/genética , Saccharomyces cerevisiae/metabolismo , Estresse Fisiológico , Fatores de Transcrição/genética , Vigna/metabolismo , Antioxidantes/metabolismo , Vias Biossintéticas/genética , DNA/metabolismo , Dimerização , Engenharia Metabólica/métodos , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Ativação Transcricional , Complexo Vitamínico B/metabolismo
19.
Am J Clin Nutr ; 114(4): 1560-1573, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34113959

RESUMO

BACKGROUND: Little is known regarding the associations between maternal factors and B-vitamin and choline concentrations in early milk and the trajectories of these vitamins during lactation. OBJECTIVES: In this hypothesis-generating study, we modeled the association between maternal and offspring factors and longitudinal changes in milk B-vitamin and choline concentrations throughout lactation. METHODS: A hundred women were studied in a prospective birth cohort and milk samples from 52 women were collected at 2-8 d, 76 women at 28-50 d, and 42 women at 88-119 d postpartum. Maternal dietary intake during pregnancy and lactation was assessed by an FFQ. Linear mixed-effects models with interaction terms were used to evaluate changes in milk B-vitamin and choline concentrations over time based on maternal factors and the early postpartum concentrations of these micronutrients. RESULTS: The women with higher early postpartum milk concentrations of niacin (ßinteraction = -0.02; SE = 0.00; P < 0.001), pantothenic acid (ßinteraction = -0.10; SE = 2.56; P < 0.001), vitamin B-12 (ßinteraction= -0.10; SE = 0.03; P < 0.001), and choline (ßinteraction= -0.90; SE = 0.18; P < 0.001) exhibited a decrease in their concentrations throughout lactation. The participants with overweight and obesity prepregnancy experienced an increase in milk vitamin B-12 concentrations over time (ßinteraction = 0.04; SE = 0.02; P = 0.06). In contrast, a decrease in vitamin B-12 concentration was observed among women with vitamin B-12 intake below the RDA during pregnancy (ßinteraction= -0.08; SE = 0.05; P = 0.07). The women with niacin intake below the RDA during lactation experienced an increase in milk concentrations over time (ßinteraction = 0.01; SE = 0.01; P = 0.03). A gestational age at birth >40 wk was associated with an increase in milk choline concentration throughout lactation (ßinteraction = 0.54; SE = 0.16; P< 0.01). CONCLUSIONS: Changes in B-vitamin and choline concentrations in human milk over time may be associated with the early concentrations of these micronutrients in milk, maternal prepregnancy BMI, dietary intake, and gestational age at delivery.


Assuntos
Colina/administração & dosagem , Leite Humano/química , Complexo Vitamínico B/administração & dosagem , Adolescente , Adulto , Colina/química , Colina/metabolismo , Estudos de Coortes , Feminino , Humanos , Lactação , Leite Humano/metabolismo , Fatores de Tempo , Complexo Vitamínico B/química , Complexo Vitamínico B/metabolismo , Adulto Jovem
20.
Am J Clin Nutr ; 114(2): 578-587, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-33964857

RESUMO

BACKGROUND: Elevated plasma homocysteine has been found to be associated with an increased risk of osteoporosis, especially hip and vertebral fractures. The plasma concentration of homocysteine is dependent on the activities of several B vitamin-dependent enzymes, such as methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR), and cystathionine ß-synthase (CBS). OBJECTIVES: We investigated whether genetic variants in some of the genes involved in 1 carbon metabolism modify the association of B vitamin-related measures with bone mineral density (BMD) and strength. METHODS: We measured several B vitamins and biomarkers in participants of the Framingham Offspring Study, and performed analyses of methylmalonic acid (MMA) continuously and <210 nmol/L; pyridoxal-5'-phosphate; vitamin B-12 continuously and ≥258 pmol/L; and folate. The outcomes of interest included areal and volumetric BMD, measured by DXA and quantitative computed tomography (QCT), respectively. We evaluated associations between the bone measures and interactions of single nucleotide polymorphism with a B vitamin or biomarker in Framingham participants (n = 4310 for DXA and n = 3127 for QCT). For analysis of DXA, we validated the association results in the B-PROOF cohort (n = 1072). Bonferroni-corrected locus-wide significant thresholds were defined to account for multiple testing. RESULTS: The interactions between rs2274976 and vitamin B-12 and rs34671784 and MMA <210 nmol/L were associated with lumbar spine BMD, and the interaction between rs6586281 and vitamin B-12 ≥258 pmol/L was associated with femoral neck BMD. For QCT-derived traits, 62 interactions between genetic variants and B vitamins and biomarkers were identified. CONCLUSIONS: Some genetic variants in the 1-carbon methylation pathway modify the association of B vitamin and biomarker concentrations with bone density and strength.  These interactions require further replication and functional validation for a mechanistic understanding of the role of the 1-carbon metabolism pathway on BMD and risks of fracture.


Assuntos
Densidade Óssea/fisiologia , Variação Genética , Ácido Metilmalônico/sangue , Complexo Vitamínico B/sangue , Adolescente , Adulto , Idoso , Densidade Óssea/genética , Criança , Pré-Escolar , Feminino , Ácido Fólico/sangue , Ácido Fólico/metabolismo , Genótipo , Humanos , Masculino , Ácido Metilmalônico/metabolismo , Pessoa de Meia-Idade , Vitamina B 12/sangue , Vitamina B 12/metabolismo , Vitamina B 6/sangue , Vitamina B 6/metabolismo , Complexo Vitamínico B/metabolismo , Adulto Jovem
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