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1.
Mol Cell ; 69(6): 923-937.e8, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29547721

RESUMEN

Dietary supplements such as vitamins and minerals are widely used in the hope of improving health but may have unidentified risks and side effects. In particular, a pathogenic link between dietary supplements and specific oncogenes remains unknown. Here we report that chondroitin-4-sulfate (CHSA), a natural glycosaminoglycan approved as a dietary supplement used for osteoarthritis, selectively promotes the tumor growth potential of BRAF V600E-expressing human melanoma cells in patient- and cell line-derived xenograft mice and confers resistance to BRAF inhibitors. Mechanistically, chondroitin sulfate glucuronyltransferase (CSGlcA-T) signals through its product CHSA to enhance casein kinase 2 (CK2)-PTEN binding and consequent phosphorylation and inhibition of PTEN, which requires CHSA chains and is essential to sustain AKT activation in BRAF V600E-expressing melanoma cells. However, this CHSA-dependent PTEN inhibition is dispensable in cancer cells expressing mutant NRAS or PI3KCA, which directly activate the PI3K-AKT pathway. These results suggest that dietary supplements may exhibit oncogene-dependent pro-tumor effects.


Asunto(s)
Carcinógenos/toxicidad , Transformación Celular Neoplásica/genética , Sulfatos de Condroitina/toxicidad , Suplementos Dietéticos/toxicidad , Melanoma/inducido químicamente , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Neoplasias Cutáneas/inducido químicamente , Animales , Antinematodos/farmacología , Quinasa de la Caseína II/metabolismo , Proliferación Celular/efectos de los fármacos , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Femenino , GTP Fosfohidrolasas/genética , Células HEK293 , Células HT29 , Humanos , Melanoma/tratamiento farmacológico , Melanoma/enzimología , Melanoma/genética , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos NOD , Ratones Desnudos , Ratones Transgénicos , Células 3T3 NIH , Proteínas Nucleares/genética , Fosfohidrolasa PTEN/antagonistas & inhibidores , Fosfohidrolasa PTEN/metabolismo , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/enzimología , Neoplasias Cutáneas/genética , Factores de Transcripción/genética , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Clin Infect Dis ; 78(5): 1162-1169, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38113446

RESUMEN

BACKGROUND: Among individuals with vitamin D deficiency, daily vitamin D supplementation appears to lower risk of acute respiratory infection. However, recent trials, in different populations and using different regimens, have yielded null results. We investigated the effect of daily vitamin D supplementation (vs placebo) on risk of upper respiratory infection (URI) in older adults. METHODS: The VITamin D and OmegA-3 TriaL (VITAL) is a randomized, double-blind, placebo-controlled trial of supplemental vitamin D and/or omega-3 fatty acids in generally healthy men (age ≥50 years) and women (age ≥55 years). This prespecified analysis focuses on vitamin D3 (2000 IU/day) versus placebo in the 15 804 (61%) participants with baseline serum total 25-hydroxyvitamin D level. The primary outcome was self-report of a recent URI at 1-year follow-up. RESULTS: Participants had a mean age of 68 years and 51% were women; 76% were non-Hispanic White, 16% Black, and 8% other race/ethnicity. The mean 25-hydroxyvitamin D level at baseline was 31 (standard deviation, 10) ng/mL, with <12 ng/mL in 2.4%. The overall effect of vitamin D supplementation on recent URI was nonsignificant (odds ratio [OR], 0.96 [95% confidence interval {CI}, .86-1.06]). In the prespecified subgroup of primary interest (<12 ng/mL and denied taking concurrent vitamin D), which had only 255 participants, vitamin D supplementation was nonsignificant (OR, 0.60 [95% CI, .28-1.30]). Statistical power to assess effect modification in other subgroups was limited. CONCLUSIONS: In older adults not selected for vitamin D deficiency, supplemental vitamin D did not lower URI risk overall. Whether effects differ in subgroups requires further study. Clinical Trials Registration. NCT01169259.


Asunto(s)
Suplementos Dietéticos , Infecciones del Sistema Respiratorio , Vitamina D , Humanos , Infecciones del Sistema Respiratorio/prevención & control , Infecciones del Sistema Respiratorio/epidemiología , Masculino , Femenino , Anciano , Vitamina D/sangre , Vitamina D/análogos & derivados , Vitamina D/administración & dosificación , Método Doble Ciego , Persona de Mediana Edad , Deficiencia de Vitamina D/tratamiento farmacológico , Deficiencia de Vitamina D/complicaciones , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-3/uso terapéutico
3.
Curr Issues Mol Biol ; 46(9): 9916-9927, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39329943

RESUMEN

Dermatan sulfate and chondroitin sulfate are dietary supplements that can be utilized as prophylactics against thrombus formation. Low-molecular-weight dermatan sulfate (LMWDS) is particularly advantageous due to its high absorbability. The enzymatic synthesis of low-molecular-weight dermatan sulfates (LMWDSs) using chondroitin B lyase is a sustainable and environmentally friendly approach to manufacturing. However, the industrial application of chondroitin B lyases is severely hampered by their low catalytic activity. To improve the activity, a semi-rational design strategy of engineering the substrate-binding domain of chondroitin B lyase was performed based on the structure. The binding domain was subjected to screening of critical residues for modification using multiple sequence alignments and molecular docking. A total of thirteen single-point mutants were constructed and analyzed to assess their catalytic characteristics. Out of these, S90T, N103C, H134Y, and R159K exhibited noteworthy enhancements in activity. This study also examined combinatorial mutagenesis and found that the mutant H134Y/R159K exhibited a substantially enhanced catalytic activity of 1266.74 U/mg, which was 3.21-fold that of the wild-type one. Molecular docking revealed that the enhanced activity of the mutant could be attributed to the formation of new hydrogen bonds and hydrophobic interactions with the substrate as well as neighbor residues. The highly active mutant would benefit the utilization of chondroitin B lyase in pharmaceuticals and functional foods.

4.
Mol Hum Reprod ; 30(4)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38366926

RESUMEN

5,10-Methylenetetrahydrofolate reductase (MTHFR) is an enzyme that plays a key role in providing methyl groups for DNA methylation, including during spermatogenesis. A common genetic variant in humans (MTHFR 677C>T) results in reduced enzyme activity and has been linked to various disorders, including male infertility. A new animal model has been created by reproducing the human equivalent of the polymorphism in mice using CRISPR/Cas9. Biochemical parameters in the Mthfr 677TT mice recapitulate alterations found in MTHFR 677TT men. Our aims were to characterize the sperm DNA methylome of the Mthfr 677CC and TT mice on a control diet (2 mg folic acid/kg diet) and assess the effects of folic acid supplementation (10 mg/kg diet) on the sperm DNA methylome. Body and reproductive organ weights, testicular sperm counts, and histology were examined. DNA methylation in sperm was assessed using bisulfite pyrosequencing and whole-genome bisulfite sequencing (WGBS). Reproductive parameters and locus-specific imprinted gene methylation were unaffected by genotype or diet. Using WGBS, sperm from 677TT mice had 360 differentially methylated tiles as compared to 677CC mice, predominantly hypomethylation (60% of tiles). Folic acid supplementation mostly caused hypermethylation in sperm of males of both genotypes and was found to partially correct the DNA methylation alterations in sperm associated with the TT genotype. The new mouse model will be useful in understanding the role of MTHFR deficiency in male fertility and in designing folate supplementation regimens for the clinic.


Asunto(s)
Metilación de ADN , Metilenotetrahidrofolato Reductasa (NADPH2) , Sulfitos , Masculino , Humanos , Animales , Ratones , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/metabolismo , Semen , Espermatozoides/metabolismo , Ácido Fólico/farmacología , Genotipo , Suplementos Dietéticos
5.
Metab Eng ; 84: 48-58, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38810867

RESUMEN

3-Hydroxy-3-methylbutyrate (HMB) is a five-carbon branch-chain hydroxy acid currently used as a dietary supplement to treat sarcopenia and exercise training. However, its current production relies on conventional chemical processes which require toxic substances and are generally non-sustainable. While bio-based syntheses of HMB have been developed, they are dependent on biotransformation of its direct precursors which are generally costly. Therefore, in this work, we developed a synthetic de novo HMB biosynthetic pathway that enables HMB production from renewable resources. This novel HMB biosynthesis employs heterologous enzymes from mevalonate pathway and myxobacterial iso-fatty acid pathway for converting acetyl-CoA to HMB-CoA. Subsequently, HMB-CoA is hydrolyzed by a thioesterase to yield HMB. Upon expression of this pathway, our initial Escherichia coli strain produced 660 mg/L of HMB from glucose in 48 hours. Through optimization of coenzyme A removal from HMB-CoA and genetic operon structure, our final strain achieved HMB production titer of 17.7 g/L in glucose minimal media using a bench-top bioreactor. This engineered strain was further demonstrated to produce HMB from other renewable carbon sources such as xylose, glycerol, and acetate. The results from this work provided a flexible and environmentally benign method for producing HMB.


Asunto(s)
Escherichia coli , Ingeniería Metabólica , Escherichia coli/genética , Escherichia coli/metabolismo , Valeratos/metabolismo , Ácido Mevalónico/metabolismo
6.
Annu Rev Nutr ; 43: 179-197, 2023 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-37196365

RESUMEN

Precise dietary assessment is critical for accurate exposure classification in nutritional research, typically aimed at understanding how diet relates to health. Dietary supplement (DS) use is widespread and represents a considerable source of nutrients. However, few studies have compared the best methods to measure DSs. Our literature review on the relative validity and reproducibility of DS instruments in the United States [e.g., product inventories, questionnaires, and 24-h dietary recalls (24HR)] identified five studies that examined validity (n = 5) and/or reproducibility (n = 4). No gold standard reference method exists for validating DS use; thus, each study's investigators chose the reference instrument used to measure validity. Self-administered questionnaires agreed well with 24HR and inventory methods when comparing the prevalence of commonly used DSs. The inventory method captured nutrient amounts more accurately than the other methods. Reproducibility (over 3 months to 2.4 years) of prevalence of use estimates on the questionnaires was acceptable for common DSs. Given the limited body of research on measurement error in DS assessment, only tentative conclusions on these DS instruments can be drawn at present. Further research is critical to advancing knowledge in DS assessment for research and monitoring purposes.


Asunto(s)
Dieta , Suplementos Dietéticos , Humanos , Estados Unidos , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Nutrientes
7.
Am J Kidney Dis ; 83(6): 803-815, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38372687

RESUMEN

Magnesium is ubiquitous in nature. It sits at the origin of the food chain, occupying the center of chlorophyl in plants. In humans, magnesium is critical to diverse molecular and catalytic processes, including energy transfer and maintenance of the genome. Despite its abundance, hypomagnesemia is common and often goes undiagnosed. This is in spite of epidemiologic data linking low magnesium with chronic diseases including diabetes mellitus. Clinically significant hypermagnesemia is encountered less frequently, but the presentation may be dramatic. Advances in molecular biology and the elucidation of the genetic causes of magnesium disorders have enhanced our understanding of their pathophysiology. Treatment approaches are also changing. The repurposing of newer medications, such as sodium/glucose cotransporter 2 inhibitors, offers new therapeutic options. In this review we integrate knowledge in this rapidly evolving field to provide clinicians and trainees with a resource for approaching common clinical scenarios involving magnesium disorders.


Asunto(s)
Deficiencia de Magnesio , Magnesio , Humanos , Magnesio/sangre , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico
8.
Electrophoresis ; 45(11-12): 1041-1053, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38477690

RESUMEN

In this paper, the development and application of a multiple heart-cutting achiral-chiral LC-LC method (mLC-LC) for the analysis of dansylated (Dns) branched-chain amino acids in commercial tablets are described. In the first dimension, a Waters Xbridge RP C18 achiral column was used under gradient conditions with buffered aqueous solution and acetonitrile. The elution order Dns-valine (Dns-Val) < Dns-isoleucine (Dns-Ile) < Dns-leucine (Dns-Leu) turned out with full resolution between adjacent peaks: 7.25 and 1.50 for the Val/Ile and the Ile/Leu pairs, respectively. A "research" validation study was performed, revealing high accuracy (Recovery%) and precision (RSD%) using two external set solutions, respectively, in the range 93.7%-104.1% and 0.4%-3.2%. The C18 column was connected via a two-position six-port switching valve to the quinidine-based Chiralpak quinidine-anion-exchange chiral column. A water/acetonitrile, 30/70 (v/v) with 50 mM ammonium acetate (apparent pH of 5.5) eluent allowed getting the three enantiomers' pairs resolved: RS equal to 4.3 for Dns-Val and Dns-Ile, and 1.7 for Dns-Leu. The application of the mLC-LC method confirmed that the content of Val, Ile, and Leu in the tablets was compliant with that labeled by the producer. Only l-enantiomers were found in the food supplement, as confirmed by LC-MS/MS analysis.


Asunto(s)
Aminoácidos de Cadena Ramificada , Comprimidos , Comprimidos/química , Aminoácidos de Cadena Ramificada/análisis , Aminoácidos de Cadena Ramificada/química , Estereoisomerismo , Cromatografía Liquida/métodos , Reproducibilidad de los Resultados , Compuestos de Dansilo/química , Espectrometría de Masas en Tándem/métodos , Modelos Lineales
9.
Hum Reprod ; 39(9): 1925-1933, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39025484

RESUMEN

STUDY QUESTION: Is periconceptional multiple-micronutrient supplement (MMS) use including folic acid (FA) compared to FA use only associated with increased embryonic growth, development, and birth weight in a high-risk population? SUMMARY ANSWER: Women with MMS intake show no significant differences in first-trimester morphological embryo development, but increased first-trimester embryonic growth trajectories and fewer neonates born small for gestational age (SGA), less than the 3rd percentile (

Asunto(s)
Suplementos Dietéticos , Desarrollo Embrionario , Ácido Fólico , Recién Nacido Pequeño para la Edad Gestacional , Humanos , Femenino , Embarazo , Ácido Fólico/administración & dosificación , Adulto , Desarrollo Embrionario/efectos de los fármacos , Recién Nacido , Estudios Prospectivos , Peso al Nacer/efectos de los fármacos , Países Bajos/epidemiología , Resultado del Embarazo , Atención Preconceptiva , Desarrollo Fetal/efectos de los fármacos , Estudios de Cohortes , Ultrasonografía Prenatal , Primer Trimestre del Embarazo
10.
Diabetes Metab Res Rev ; 40(2): e3729, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37750562

RESUMEN

AIMS: To explore the association of dietary vitamin intake from food and/or supplement with mortality in US adults with diabetes. MATERIALS AND METHODS: This prospective cohort study was conducted on 5418 US adults with diabetes from the National Health and Nutrition Examination Survey 1999-2018. Vitamin intake from food and supplements was estimated via dietary recall. Sufficient intake from food or food + supplement was defined as ≥ estimated average requirement (EAR) and ≤ tolerable upper intake level (UL), insufficient intake, < EAR; and excess intake, > UL. Medium supplementary intake was classified as > median level and ≤75th percentile; low intake, ≤ median level; and high intake, >75th percentile, as reported by supplement users. RESULTS: A total of 1601 deaths occurred among the participants over a median follow-up of 11.0 years. Cox regression analysis of the single-vitamin model demonstrated that sufficient vitamin A and folate intake from food and food + supplement and medium vitamin A and folate intake from supplement; sufficient riboflavin, niacin, and vitamin B6 intake from food and food + supplement; and sufficient thiamin and vitamin E intake from food + supplement were significantly associated with reduced all-cause mortality (all p < 0.05). In the multivitamin model, sufficient vitamin A and folate intake from food and food + supplement, medium vitamin A and folate intake from the supplement, and sufficient niacin intake from food and food + supplement were inversely associated with mortality (all p < 0.05). CONCLUSIONS: Vitamin A and folate intake from food or supplement and niacin intake from food were significantly associated with reduced mortality in US adults with diabetes.


Asunto(s)
Diabetes Mellitus , Niacina , Adulto , Humanos , Vitaminas , Encuestas Nutricionales , Vitamina A , Estudios Prospectivos , Dieta , Suplementos Dietéticos , Ácido Fólico
11.
J Nutr ; 154(5): 1665-1675, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38527736

RESUMEN

BACKGROUND: In Canada, nutrition policy, as outlined in the Nutrition for Healthy Term Infants recommendations, includes a daily vitamin D supplement of 10 µg (400 IU) for breastfed infants and young children to support adequate vitamin D status. OBJECTIVES: This study aimed to report on adherence to vitamin D supplementation recommendations for breastfed infants (≤12 months); and for children breastfed >12 mo. METHODS: Canadian Community Health Survey (paired-cycles 2015/2016 and 2017/2018) maternal experiences data for infants born 2012-2018 who received any breastmilk formed the sample (n = 7079). Whether the infant was given a vitamin D supplement (yes/no) and the frequency (daily/almost every day, 1-2/wk, or <1/wk) were surveyed. Weighted data (95% CI) were summarized according to breastfeeding history (exclusive to 6 mo and continuing; partial to 6 mo and continuing; and stopped ≤6 mo). Correlates of supplement adherence were explored using logistic regression. RESULTS: Overall, 87.1% (95% CI: 85.9%, 88.3%) of participants reported giving their infant (≤12 mo) a vitamin D supplement, and of these, 83.3% (95% CI: 81.9%, 84.7%) did so daily/almost every day, 12.4% (95% CI: 11.1%, 13.7%) did so 1-2/wk, and 4.3% (95% CI: 3.6%, 5.0%) did so <1/wk. Lower adjusted odds of adherence were observed among participants reporting: stopped breastfeeding ≤6 mo, lower education or income, recent immigration, and overweight prepregnancy body mass index; higher odds of adherence were observed in the western provinces. Regarding mothers of children >12 mo and breastfed (n = 2312), 58.0% (95% CI: 54.9%, 61.1%) gave a vitamin D supplement daily/almost every day. CONCLUSIONS: Adherence to providing a vitamin D supplement to breastfed infants is high in Canada. Nonetheless, we estimate that ∼27% of mothers are nonadherent to daily/almost every day administration of a vitamin D supplement and that adherence declines in children breastfed >12 mo. Further promotion to support uptake of the current guidance may be necessary, particularly for parents of recent immigration or lower socioeconomic status.


Asunto(s)
Lactancia Materna , Suplementos Dietéticos , Vitamina D , Humanos , Lactante , Vitamina D/administración & dosificación , Canadá , Femenino , Masculino , Adulto , Recién Nacido , Encuestas Epidemiológicas , Preescolar , Deficiencia de Vitamina D/prevención & control
12.
J Nutr ; 154(6): 1927-1935, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38615735

RESUMEN

BACKGROUND: Anemia may be associated with poor clinical outcomes among people living with human immunodeficiency virus (HIV) (PLHIV) despite highly active antiretroviral therapy (HAART). There are concerns that iron supplementation may be unsafe to prevent and treat anemia among PLHIV. OBJECTIVE: The objective of the study was to evaluate the associations of anemia and iron supplementation with mortality and viral load among PLHIV in Tanzania. METHODS: We analyzed data from a cohort of 70,442 nonpregnant adult PLHIV in Tanzania conducted between 2015 and 2019. Regression models evaluated the relationships between anemia severity and iron supplement use with mortality and unsuppressed HIV-1 viral load among all participants and stratified by whether participants were initiating or continuing HAART. RESULTS: Anemia was associated with an increased risk of mortality and unsuppressed viral load for participants who initiated or continued HAART. Iron supplement use was associated with reduced mortality risk but also had a greater risk of an unsuppressed viral load among participants continuing HAART. There was no association of iron supplement use with mortality, and unsuppressed viral load among PLHIV that were initiating HAART. There was a stronger negative association between iron supplement use and the risk of having an unsuppressed viral load among participants with stage III/IV disease compared with stage I/II disease. CONCLUSIONS: Anemia is associated with increased risk of mortality and unsuppressed viral load, but the benefits and safety of iron supplements appear to differ for those initiating compared with continuing ART as well as by HIV disease severity.


Asunto(s)
Anemia , Suplementos Dietéticos , Infecciones por VIH , Hierro , Carga Viral , Humanos , Tanzanía/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/mortalidad , Infecciones por VIH/complicaciones , Masculino , Femenino , Adulto , Anemia/mortalidad , Persona de Mediana Edad , Hierro/sangre , Hierro/administración & dosificación , Hierro/uso terapéutico , Terapia Antirretroviral Altamente Activa , Estudios de Cohortes , Adulto Joven
13.
BMC Cancer ; 24(1): 591, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750410

RESUMEN

BACKGROUND: There is little evidence that dietary supplements are beneficial for patients with breast cancer; therefore, they are usually not recommended by treatment guidelines. The aim of the present analysis was to assess the prevalence of dietary supplement (DS) intake among women before and after a breast cancer diagnosis. METHODS: Participants in the SUCCESS C lifestyle intervention study, a randomized controlled trial in women with newly diagnosed intermediate- to high-risk breast cancer, completed two questionnaires on dietary supplement intake 24 months (QS1) and 48 months (QS2) after beginning the lifestyle intervention. The study was registered on 12.17.2008 under the EU Clinical Trials Register https://www.clinicaltrialsregister.eu/ , trial registration number: 2008-005453-38. The questionnaires collected data on DS intake during the 5-year period prediagnosis (QS1) and in the period postdiagnosis (QS2). Multivariate logistic regression models were fitted to examine differences in DS intake between the two intervention groups. The groups were then pooled to examine differences in DS use between the prediagnostic and postdiagnostic period. RESULTS: A total of 320 questionnaires from 58.5% of intervention group completers and 416 questionnaires from 46.6% of low-level intervention group completers were included in the analysis. Overall, 20.2% of all respondents reported taking DS prior to their diagnosis. After a cancer diagnosis, the percentage of women taking DS significantly increased to 56.4% (p for time effect < 0.0001). No differences in DS intake between the intervention groups were observed. Single or combined preparations of vitamins and minerals/trace elements were the most frequently reported supplements. Notably, a 9-fold increase in vitamin D intake was reported postdiagnosis, where the proportion of women increased from 3.8 to 34.5%. CONCLUSION: A 3-fold increase in the reported intake of dietary supplements was seen in women after a breast cancer diagnosis. These observations underscore the need to incorporate patient education surrounding the use of dietary supplements in a treatment care plan, particularly addressing the negligible benefits as well as the potential risks and treatment interactions.


Asunto(s)
Neoplasias de la Mama , Suplementos Dietéticos , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto , Anciano , Estilo de Vida
14.
J Nutr ; 154(6): 1917-1926, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38621624

RESUMEN

BACKGROUND: Data regarding effects of small-quantity-lipid-based nutrient supplements (SQ-LNS) on maternal serum zinc concentrations (SZC) in pregnancy and lactation are limited. OBJECTIVES: The objectives of this study were to evaluate the effect of preconception compared with prenatal zinc supplementation (compared with control) on maternal SZC and hypozincemia during pregnancy and early lactation in women in low-resource settings, and assess associations with birth anthropometry. METHODS: From ∼100 women/arm at each of 3 sites (Guatemala, India, and Pakistan) of the Women First Preconception Maternal Nutrition trial, we compared SZC at 12- and 34-wk gestation (n = 651 and 838, respectively) and 3-mo postpartum (n = 742) in women randomly assigned to daily SQ-LNS containing 15 mg zinc from ≥3 mo before conception (preconception, arm 1), from ∼12 wk gestation through delivery (early pregnancy, arm 2) or not at all (control, arm 3). Birth anthropometry was examined for newborns with ultrasound-determined gestational age. Statistical analyses were performed separately for each time point. RESULTS: At 12-wk gestation and 3-mo postpartum, no statistical differences in mean SZC were observed among arms. At 34-wk, mean SZC for arms 1 and 2 were significantly higher than for arm 3 (50.3, 50.8, 47.8 µg/dL, respectively; P = 0.005). Results were not impacted by correction for inflammation or albumin concentrations. Prevalence of hypozincemia at 12-wk (<56 µg/dL) was 23% in Guatemala, 26% in India, and 65% in Pakistan; at 34 wk (<50 µg/dL), 36% in Guatemala, 48% in India, and 74% in Pakistan; and at 3-mo postpartum (<66 µg/dL) 79% in Guatemala, 91% in India, and 92% in Pakistan. Maternal hypozincemia at 34-wk was associated with lower birth length-for-age Z-scores (all sites P = 0.013, Pakistan P = 0.008) and weight-for-age Z-scores (all sites P = 0.017, Pakistan P = 0.022). CONCLUSIONS: Despite daily zinc supplementation for ≥7 mo, high rates of maternal hypozincemia were observed. The association of hypozincemia with impaired fetal growth suggests widespread zinc deficiency in these settings. This trial is registered at clinicaltrials.gov as #NCT01883193.


Asunto(s)
Suplementos Dietéticos , Lactancia , Fenómenos Fisiologicos Nutricionales Maternos , Zinc , Humanos , Femenino , Embarazo , Zinc/administración & dosificación , Zinc/sangre , Adulto , Recién Nacido , Prevalencia , Adulto Joven , Complicaciones del Embarazo , India , Estado Nutricional , Atención Preconceptiva
15.
Amino Acids ; 56(1): 29, 2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38583116

RESUMEN

L-theanine, an amino acid component of the tea leaves of Camellia sinensis, is sold in Japan as a supplement for good sleep. Although several studies in humans and mice have reported the effects of L-theanine on brain function, only a few reports have comprehensively clarified the disposition of theanine administered to mice and its effects on concentrations of other blood amino acids. In this study, we aimed to determine the changes in the blood levels of L-theanine administered to mice and amino acid composition of the serum. L-theanine were administered to four-week-old Std-ddY male mice orally or via tail vein injection. L-theanine and other amino acids in serum prepared from blood collected at different time points post-dose were labeled with phenylisothiocyanate and quantified. The serum concentration of orally administered L-theanine peaked 15 min after administration. The area under the curve for tail vein injection revealed the bioavailability of L- theanine to be approximately 70%. L-theanine administration did not affect any amino acid levels in the serum, but a significant increase in the peak area overlapping the Glycine (Gly) peak was observed 30 min after administration. L-theanine administered to mice was rapidly absorbed and eliminated, suggesting that taking L-theanine as a supplement is safe without affecting its own levels or serum levels of other amino acids. However, considering that Gly, similar to L-theanine, is used as a dietary supplement for its anxiolytic effects and to improve sleep, determining the effects of L-theanine administration on Gly is important and needs further research.


Asunto(s)
Aminoácidos , Fabaceae , Humanos , Ratones , Masculino , Animales , Glicina , Glutamatos , Disponibilidad Biológica
16.
Mol Pharm ; 21(8): 3743-3763, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38953708

RESUMEN

The coronavirus (COVID-19) pandemic has underscored the critical role of mRNA-based vaccines as powerful, adaptable, readily manufacturable, and safe methodologies for prophylaxis. mRNA-based treatments are emerging as a hopeful avenue for a plethora of conditions, encompassing infectious diseases, cancer, autoimmune diseases, genetic diseases, and rare disorders. Nonetheless, the in vivo delivery of mRNA faces challenges due to its instability, suboptimal delivery, and potential for triggering undesired immune reactions. In this context, the development of effective drug delivery systems, particularly nanoparticles (NPs), is paramount. Tailored with biophysical and chemical properties and susceptible to surface customization, these NPs have demonstrated enhanced mRNA delivery in vivo and led to the approval of several NPs-based formulations for clinical use. Despite these advancements, the necessity for developing a refined, targeted NP delivery system remains imperative. This review comprehensively surveys the biological, translational, and clinical progress in NPs-mediated mRNA therapeutics for both the prevention and treatment of diverse diseases. By addressing critical factors for enhancing existing methodologies, it aims to inform the future development of precise and efficacious mRNA-based therapeutic interventions.


Asunto(s)
COVID-19 , Sistema de Administración de Fármacos con Nanopartículas , ARN Mensajero , Humanos , ARN Mensajero/genética , ARN Mensajero/administración & dosificación , Sistema de Administración de Fármacos con Nanopartículas/química , COVID-19/prevención & control , Nanopartículas/química , Sistemas de Liberación de Medicamentos/métodos , Animales , SARS-CoV-2/efectos de los fármacos , Vacunas de ARNm
17.
Reprod Biomed Online ; 48(3): 103770, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38184959

RESUMEN

Many women undergoing IVF take supplements during treatment. The purpose of this review was to systematically review these nutritional supplements. The therapies studied are dehydroepiandrosterone (DHEA), melatonin, co-enzyme Q10 (CoQ1O), carnitine, selenium, vitamin D, myo-inositol, omega-3, Chinese herbs and dietary interventions. A literature search up to May 2023 was undertaken. The data suggest that a simple nutritional approach would be to adopt a Mediterranean diet. With regards to supplements to treat a potential poor ovarian response to ovarian stimulation, starting DHEA and COQ-10 before cycle commencement is better than control therapies. Furthermore, medication with CoQ10 may have some merit, although it is unclear whether its place is for older women, for those with a poor response to ovarian stimulation or for poor embryonic development. There appears a benefit for some IVF outcomes for the use of melatonin, although it is unclear what group of patients would derive the benefit and the appropriate dosing regimen. For women with polycystic ovary syndrome, there may be a benefit to the use of myo-inositol, although again the dosing regimen is unclear. Furthermore, the place of vitamin D supplementation has yet to be clarified, and supplementation with omega-3 free fatty acids may lead to improvements in clinical and embryological IVF outcomes.


Asunto(s)
Melatonina , Embarazo , Humanos , Femenino , Anciano , Melatonina/uso terapéutico , Fertilización In Vitro , Suplementos Dietéticos , Inositol/uso terapéutico , Vitamina D , Deshidroepiandrosterona , Inducción de la Ovulación
18.
Crit Rev Food Sci Nutr ; : 1-19, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39116016

RESUMEN

A surge of public interest in NMN supplementation has been observed in recent years. However, whether NMN supplements are effective in improving metabolic health remains unclear. The objective of the review was to assess the effects of NMN supplementation on fasting glucose, triglycerides, total cholesterol, LDL-C, and HDL-C in adults. Studies were located by searching four databases (PubMed, Embase, Cochrane, and Web of Science). Two reviewers independently conducted title/abstract and full-text screening, data extraction, and risk-of-bias assessment. Of the 4049 records reviewed, 12 studies with a total of 513 participants met the criteria for analysis. Random-effects meta-analyses found an overall significant effect of NMN supplementation in elevating blood NAD levels. However, most of the clinically relevant outcomes were not significantly different between NMN supplementation and control group. Risk-of-bias assessment using RoB2 showed some concerns in seven studies and high risk of bias in the other five studies. Together, our findings suggest that an exaggeration of the benefits of NMN supplementation may exist in the field. Although the limited number of eligible studies was sufficiently powered to detect changes in the abovementioned primary outcomes, more studies are needed to conclude about the exact effects of NMN supplementation.

19.
Eur J Vasc Endovasc Surg ; 67(4): 570-582, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38013062

RESUMEN

OBJECTIVE: Large abdominal aortic aneurysms (AAAs) present a significant mortality risk. While numerous medical interventions have been proposed, no drugs have convincingly reduced AAA progression, rupture rates, or repair risk. This systematic review and meta-analysis aimed to assess the impact of re-purposed drugs or dietary supplements on slowing expansion rates, reducing the risk of rupture, or minimising the risk of repair for individuals with AAA. METHODS: A systematic search was conducted in five databases. Both observational studies and randomised controlled trials were included. Unpublished data from two screening trials were incorporated. Risk of bias was assessed using the Newcastle-Ottawa scale and revised Cochrane risk of bias tool. Meta-analyses were performed for each identified drug subclass and were stratified by overall risk of bias. Results were reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Of 7 484 screened studies, 39 met the inclusion criteria. No studies on dietary supplements were included. A total of 84 cohorts were derived from the included studies, and twelve distinct drug groups underwent meta-analyses. Two drug groups, metformin and statins, were statistically significant in slowing AAA growth. No low risk of bias studies were included for these two drug groups, and the results had very high heterogeneity (I2 > 80%). Both groups had a GRADE certainty of very low. Metformin, excluding high risk of bias studies, presented an estimated mean growth difference of AAA diameter between users and non-users of -0.73 mm/year, whilst statins had an overall estimated mean difference of -0.84 mm/year. CONCLUSION: This systematic review and meta-analysis suggests that metformin and statins may provide some effect in slowing AAA progression. However, no definitive evidence was found for any of the investigated drugs included in this study. Further research is needed to identify effective medical treatments for AAA progression with more robust methodology.


Asunto(s)
Aneurisma de la Aorta Abdominal , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Metformina , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/tratamiento farmacológico
20.
Prostaglandins Other Lipid Mediat ; 174: 106877, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39079610

RESUMEN

There is controversial data on the impacts of bitter melon (Momordica charantia) supplementations on anthropometric indices. Thus, we aimed to clarify this role of bitter melon through a systematic review, and meta-analysis of the trials. All clinical trials conducted on the impact of bitter melon on anthropometric indices were published until August 2023 in PubMed, Web of Sciences, Scopus, Embase, and Cochrane Library web databases included. Overall, 10 studies with 448 individuals were included in the meta-analysis. Meta-analysis of 10 trials with 448 participants revealed no significant reductions in body weight (BW) (WMD: 0.04 Kg; 95 %CI: -0.16-0.25; P =0.651), body mass index (BMI) (WMD: -0.18 kg/m2; 95 %CI: -0.43-0.07; P =0.171), waist circumference (WC) (WMD: -0.95 cm; 95 % CI: -3.05-1.16; p =0.372), and percentage of body fat (PBF) (WMD: -0.99; 95 % CI: -2.33-0.35; p =0.141) following bitter melon supplementation. There was no significant impact of bitter melon supplementation on BW, BMI, WC, and PBF. More large-scale and high-quality RCTs are necessary to confirm these results.


Asunto(s)
Momordica charantia , Adulto , Humanos , Índice de Masa Corporal , Peso Corporal/efectos de los fármacos , Momordica charantia/química , Extractos Vegetales/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto
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