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Mangoni AA, Zinellu A. Transsulfuration and folate pathways in rheumatoid arthritis: A systematic review and meta-analysis. Eur J Clin Invest 2024; 54:e14158. [PMID: 38214126 DOI: 10.1111/eci.14158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 11/27/2023] [Accepted: 12/03/2023] [Indexed: 01/13/2024]
Abstract
BACKGROUND Metabolomic assessment of the transsulfuration and folic acid biochemical pathways could lead to the identification of promising biomarkers of nitric oxide dysregulation and oxidative stress in rheumatoid arthritis (RA). METHODS We conducted a systematic review and meta-analysis of transsulfuration (methionine, homocysteine, and cysteine) and folic acid (folic acid, vitamin B6 , and vitamin B12 ) metabolites in RA patients in remission and healthy controls. Electronic databases were searched from inception to 15 July 2023 for relevant articles. We assessed the risk of bias using the JBI checklist and the certainty of evidence using GRADE. RESULTS In 28 eligible studies, compared to controls, RA patients had significantly higher concentrations of homocysteine (standardized mean difference, SMD = 0.74, 95% CI 0.54-0.93, p < 0.001; low certainty of evidence) and methionine (SMD = 1.00, 95% CI 0.57-1.44, p < 0.001; low certainty) and lower concentrations of vitamin B6 (SMD = -6.62, 95% CI -9.65 to -3.60, p < 0.001; low certainty). By contrast, there were non-significant between-group differences in vitamin B12 and folic acid. In meta-regression and subgroup analysis, there were no associations between the effect size and several study and patient characteristics except for homocysteine (year of publication, C-reactive protein, triglycerides, and analytical method) and folic acid (biological matrix). CONCLUSIONS The results of our study suggest that homocysteine, methionine, and vitamin B6 are promising biomarkers to assess nitric oxide dysregulation and oxidative stress in RA. (PROSPERO registration number: CRD42023461081).
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Affiliation(s)
- Arduino A Mangoni
- Discipline of Clinical Pharmacology, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia
- Department of Clinical Pharmacology, Flinders Medical Centre, Southern Adelaide Local Health Network, Adelaide, South Australia, Australia
| | - Angelo Zinellu
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
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Bokayeva K, Jamka M, Banaszak M, Makarewicz-Bukowska A, Adamczak A, Chrobot M, Janicka A, Jaworska N, Walkowiak J. The Effect of Folic Acid Supplementation on Endothelial Function and Arterial Stiffness Markers in Adults: A Systematic Review and Meta-Analysis. Healthcare (Basel) 2023; 11:2524. [PMID: 37761721 PMCID: PMC10531078 DOI: 10.3390/healthcare11182524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/07/2023] [Accepted: 09/10/2023] [Indexed: 09/29/2023] Open
Abstract
Folic acid might improve endothelial function, but the results are inconclusive. This systematic review evaluated the effect of folic acid supplementation on endothelial parameters and arterial stiffness in adults. The study protocol was registered with the PROSPERO database (CRD42021290195). The PubMed, Web of Sciences, Cochrane and Scopus databases were searched to identify English-language randomised controlled trials of the effect of folate supplementation on arterial stiffness and endothelial function markers in adults. There were significant differences between the effect of folic acid and placebo on flow-mediated dilation (random-effects model, standardized mean differences (SMD): 0.888, 95% confidence interval (CI): 0.447, 1.329, p < 0.001) and monocyte chemotactic protein 1 (random-effects model, SMD: -1.364, 95% CI: -2.164, -0.563, p < 0.001), but there was no significant difference in the central pulse wave velocity (fixed-effects model, SMD: -0.069, 95% CI: -0.264, 0.125, p = 0.485) and peripheral pulse wave velocity (fixed-effects model, SMD: -0.093, 95% CI: -0.263, 0.077, p = 0.284). In conclusion, folic acid might have a favourable effect on endothelial function but may not affect arterial stiffness. Further studies are needed to confirm these results.
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Affiliation(s)
- Kamila Bokayeva
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznań, Poland; (K.B.); (M.J.); (A.M.-B.); (A.A.); (M.C.); (A.J.); (N.J.)
| | - Małgorzata Jamka
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznań, Poland; (K.B.); (M.J.); (A.M.-B.); (A.A.); (M.C.); (A.J.); (N.J.)
| | - Michalina Banaszak
- Department of Bromatology, Poznan University of Medical Sciences, Rokietnicka Str. 3, 60-806 Poznań, Poland;
| | - Aleksandra Makarewicz-Bukowska
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznań, Poland; (K.B.); (M.J.); (A.M.-B.); (A.A.); (M.C.); (A.J.); (N.J.)
| | - Ada Adamczak
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznań, Poland; (K.B.); (M.J.); (A.M.-B.); (A.A.); (M.C.); (A.J.); (N.J.)
| | - Maria Chrobot
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznań, Poland; (K.B.); (M.J.); (A.M.-B.); (A.A.); (M.C.); (A.J.); (N.J.)
| | - Adrianna Janicka
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznań, Poland; (K.B.); (M.J.); (A.M.-B.); (A.A.); (M.C.); (A.J.); (N.J.)
| | - Natalia Jaworska
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznań, Poland; (K.B.); (M.J.); (A.M.-B.); (A.A.); (M.C.); (A.J.); (N.J.)
| | - Jarosław Walkowiak
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznań, Poland; (K.B.); (M.J.); (A.M.-B.); (A.A.); (M.C.); (A.J.); (N.J.)
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Zinellu A, Mangoni AA. Arginine, Transsulfuration, and Folic Acid Pathway Metabolomics in Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis. Cells 2023; 12:2180. [PMID: 37681911 PMCID: PMC10486395 DOI: 10.3390/cells12172180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/13/2023] [Accepted: 08/29/2023] [Indexed: 09/09/2023] Open
Abstract
There is an increasing interest in biomarkers of nitric oxide dysregulation and oxidative stress to guide management and identify new therapeutic targets in patients with chronic obstructive pulmonary disease (COPD). We conducted a systematic review and meta-analysis of the association between circulating metabolites within the arginine (arginine, citrulline, ornithine, asymmetric, ADMA, and symmetric, SDMA dimethylarginine), transsulfuration (methionine, homocysteine, and cysteine) and folic acid (folic acid, vitamin B6, and vitamin B12) metabolic pathways and COPD. We searched electronic databases from inception to 30 June 2023 and assessed the risk of bias and the certainty of evidence. In 21 eligible studies, compared to healthy controls, patients with stable COPD had significantly lower methionine (standardized mean difference, SMD = -0.50, 95% CI -0.95 to -0.05, p = 0.029) and folic acid (SMD = -0.37, 95% CI -0.65 to -0.09, p = 0.009), and higher homocysteine (SMD = 0.78, 95% CI 0.48 to 1.07, p < 0.001) and cysteine concentrations (SMD = 0.34, 95% CI 0.02 to 0.66, p = 0.038). Additionally, COPD was associated with significantly higher ADMA (SMD = 1.27, 95% CI 0.08 to 2.46, p = 0.037), SDMA (SMD = 3.94, 95% CI 0.79 to 7.08, p = 0.014), and ornithine concentrations (SMD = 0.67, 95% CI 0.13 to 1.22, p = 0.015). In subgroup analysis, the SMD of homocysteine was significantly associated with the biological matrix assessed and the forced expiratory volume in the first second to forced vital capacity ratio, but not with age, study location, or analytical method used. Our study suggests that the presence of significant alterations in metabolites within the arginine, transsulfuration, and folic acid pathways can be useful for assessing nitric oxide dysregulation and oxidative stress and identifying novel treatment targets in COPD. (PROSPERO registration number: CRD42023448036.).
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Affiliation(s)
- Angelo Zinellu
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy;
| | - Arduino A. Mangoni
- Discipline of Clinical Pharmacology, College of Medicine and Public Health, Flinders University, Bedford Park, SA 5042, Australia
- Department of Clinical Pharmacology, Flinders Medical Centre, Southern Adelaide Local Health Network, Bedford Park, SA 5042, Australia
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Ramos-Lopez O, Martinez-Urbistondo D, Vargas-Nuñez JA, Martinez JA. The Role of Nutrition on Meta-inflammation: Insights and Potential Targets in Communicable and Chronic Disease Management. Curr Obes Rep 2022; 11:305-335. [PMID: 36258149 PMCID: PMC9579631 DOI: 10.1007/s13679-022-00490-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/27/2022] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW Chronic low-grade inflammation may contribute to the onset and progression of communicable and chronic diseases. This review examined the effects and eventual mediation roles of different nutritional factors on inflammation. RECENT FINDINGS Potential nutritional compounds influencing inflammation processes include macro and micronutrients, bioactive molecules (polyphenols), specific food components, and culinary ingredients as well as standardized dietary patterns, eating habits, and chrononutrition features. Therefore, research in this field is still required, taking into account critical aspects of heterogeneity including type of population, minimum and maximum intakes and adverse effects, cooking methods, physiopathological status, and times of intervention. Moreover, the integrative analysis of traditional variables (age, sex, metabolic profile, clinical history, body phenotype, habitual dietary intake, physical activity levels, and lifestyle) together with individualized issues (genetic background, epigenetic signatures, microbiota composition, gene expression profiles, and metabolomic fingerprints) may contribute to the knowledge and prescription of more personalized treatments aimed to improving the precision medical management of inflammation as well as the design of anti-inflammatory diets in chronic and communicable diseases.
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Affiliation(s)
- Omar Ramos-Lopez
- Medicine and Psychology School, Autonomous University of Baja California, Universidad 14418, UABC, Parque Internacional Industrial Tijuana, 22390, Tijuana, Baja California, Mexico.
| | | | - Juan A Vargas-Nuñez
- Servicio de Medicina Interna, Hospital Universitario Puerta de Hierro Majadahonda, 28222, Madrid, Spain
- Department of Medicine, Facultad de Medicina, Universidad Autónoma de Madrid, 28029, Madrid, Spain
| | - J Alfredo Martinez
- Precision Nutrition and Cardiometabolic Health, IMDEA Food Institute, CEI UAM+CSIC, 28049, Madrid, Spain
- Department of Nutrition, Food Science, Physiology and Toxicology, Centre for Nutrition Research, University of Navarra, 31009, Pamplona, Spain
- Spanish Biomedical Research Centre in Physiopathology of Obesity and Nutrition (CIBERobn), 28029, Madrid, Spain
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The Effects of Folic Acid Supplementation on Pro-inflammatory Mediators: a Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials. Clin Ther 2021; 43:e346-e363. [PMID: 34857394 DOI: 10.1016/j.clinthera.2021.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 09/27/2021] [Accepted: 10/06/2021] [Indexed: 12/31/2022]
Abstract
PURPOSE Despite extensive research, findings regarding the effects of folic acid supplementation on inflammatory mediators have been controversial and inconclusive. This study therefore aimed to summarize the findings of all available clinical trials regarding the effects of folic acid supplementation on inflammatory biomarkers in adults. METHODS A systematic search was conducted of PubMed/MEDLINE, Scopus, Web of Science, EMBASE, and Google Scholar until April 2020. All randomized controlled trials that examined the influence of folic acid supplementation on C-reactive protein, interleukin 6 (IL-6), and tumor necrosis factor-α (TNF-α) were included. Pooled effect sizes were calculated based on the random effects model, and dose-response analysis was modeled by using a fractional polynomial model. FINDINGS In total, 18 randomized controlled trials involving 2286 participants were analyzed. Folic acid supplementation significantly reduced serum levels of C-reactive protein (mean difference [MD], -0.21 mg/L; 95% CI, -0.41 to -0.01; n = 16), TNF-α (MD, -14.88 pg/mL; 95% CI, -23.68 to -6.09; n = 10), and IL-6 (MD, -0.93 pg/mL; 95% CI, -1.72 to -0.14; n = 11). Subgroup analyses suggested a significant reduction at doses ≤5 mg/d and studies longer than 12 weeks in duration. A significant nonlinear association was also found between folic acid dosage (Pnonlinearity <0.001) and duration of administration (Pnonlinearity <0.001) with serum TNF-α levels. IMPLICATIONS This meta-analysis indicates the beneficial effects of folic acid supplementation on pro-inflammatory cytokines. Further studies with a longer duration of administration, higher doses, and larger sample sizes should be performed exclusively on patients with chronic inflammatory disorders to elucidate the favorable role of folate intake on inflammatory biomarkers. International Prospective Register of Systematic Reviews identifier: CRD42021249947.
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Effects of Folic Acid Supplementation on Inflammatory Markers: A Grade-Assessed Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials. Nutrients 2021; 13:nu13072327. [PMID: 34371837 PMCID: PMC8308638 DOI: 10.3390/nu13072327] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 06/29/2021] [Accepted: 07/02/2021] [Indexed: 12/20/2022] Open
Abstract
It has been theorized that folic acid supplementation improves inflammation. However, its proven effects on inflammatory markers are unclear as clinical studies on this topic have produced inconsistent results. To bridge this knowledge gap, this systematic review and meta-analysis of randomized controlled trials (RCTs) aimed to evaluate the effects of folic acid supplementation on serum concentrations of the inflammatory markers C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Methods: To identify eligible RCTs, a systematic search up to April 2021 was completed in PubMed/Medline, Scopus, Web of Science, EMBASE, Cochrane databases, and Google Scholar using relevant keywords. A fix or random-effects model was utilized to estimate the weighted mean difference (WMD) and 95% confidence interval (95% CI). Results: Twelve RCTs were included in the present meta-analysis. The pooled analysis revealed that serum concentrations of CRP (WMD: −0.59 mg/L, 95% CI −0.85 to −0.33, p < 0.001) were significantly reduced following folic acid supplementation compared to placebo, but did not affect serum concentrations of IL-6 (WMD: −0.12, 95% CI −0.95 to 0.72 pg/mL, p = 0.780) or TNF-α (WMD: −0.18, 95% CI −0.86 to 0.49 pg/mL, p = 0.594). The dose–response analysis demonstrated a significant relationship between an elevated dosage of folic acid supplementation and lower CRP concentrations (p = 0.002). Conclusions: We found that folic acid supplementation may improve inflammation by attenuating serum concentrations of CRP but without significant effects on IL-6 and TNF-α. Future RCTs including a larger number of participants and more diverse populations are needed to confirm and expand our findings.
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Asbaghi O, Ashtary-Larky D, Bagheri R, Nazarian B, Pourmirzaei Olyaei H, Rezaei Kelishadi M, Nordvall M, Wong A, Dutheil F, Naeini AA. Beneficial effects of folic acid supplementation on lipid markers in adults: A GRADE-assessed systematic review and dose-response meta-analysis of data from 21,787 participants in 34 randomized controlled trials. Crit Rev Food Sci Nutr 2021; 62:8435-8453. [PMID: 34002661 DOI: 10.1080/10408398.2021.1928598] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Folic acid supplementation has received considerable attention in the literature, yet there is a large discrepancy in its effects on lipid markers in adults. Therefore, this systematic review and meta-analysis of 38 randomized controlled trials (RCTs) evaluated the effects of folic acid supplementation on triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol concentrations in a cohort of 21,787 participants. A systematic search current as of March 2021 was performed in PubMed/Medline, Scopus, Web of Science, and Embase using relevant keywords to identify eligible studies. A fix or random-effects model was used to estimate the weighted mean difference (WMD) and 95% confidence intervals (CIs). Thirty-four RCTs were included in this meta-analysis. The pooled analysis revealed that serum TG (WMD: -9.78 mg/dL; 95% CI: -15.5 to -4.00; p = 0.001, I2=0.0%, p = 0.965) and TC (WMD: -3.96 mg/dL; 95% CI: -6.71 to -1.21; p = 0.005, I2=46.9%, p = 0.001) concentrations were significantly reduced following folic acid supplementation compared to placebo. However, folic acid supplementation did not affect serum concentrations of LDL (WMD: -0.97 mg/dL; 95% CI: -6.82 to 4.89; p = 0.746, I2=60.6%, p < 0.001) or HDL cholesterol (WMD: 0.44 mg/dL; 95% CI: -0.53 to 1.41; p = 0.378, I2= 0.0%, p = 0.831). A significant dose-response relationship was observed between the dose of folic acid supplementation and serum concentrations of HDL cholesterols (r = 2.22, p = 0.047). Folic acid supplementation reduced serum concentrations of TG and TC without affecting LDL or HDL cholesterols. Future large RCTs on various populations are needed to show further beneficial effects of folic acid supplementation on lipid profile.
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Affiliation(s)
- Omid Asbaghi
- Student Research Committee, Lorestan University of Medical Sciences, Khorramabad, Iran
| | - Damoon Ashtary-Larky
- Nutrition and Metabolic Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Reza Bagheri
- Department of Exercise Physiology, University of Isfahan, Isfahan, Iran
| | - Behzad Nazarian
- Student Research Committee, Lorestan University of Medical Sciences, Khorramabad, Iran
| | | | - Mahnaz Rezaei Kelishadi
- Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Michael Nordvall
- Department of Health and Human Performance, Marymount University, Arlington, Virginia, USA
| | - Alexei Wong
- Department of Health and Human Performance, Marymount University, Arlington, Virginia, USA
| | - Frédéric Dutheil
- Université Clermont Auvergne, CNRS, LaPSCo, Physiological and Psychosocial Stress, CHU Clermont-Ferrand, University Hospital of Clermont-Ferrand, Preventive and Occupational Medicine, Clermont-Ferrand, France
| | - Amirmansour Alavi Naeini
- Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
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8
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Interaction of serum calcium and folic acid treatment on first stroke in hypertensive males. Clin Nutr 2021; 40:2381-2388. [DOI: 10.1016/j.clnu.2020.10.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 12/13/2022]
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The Effect of Vitamin Supplementation on Subclinical Atherosclerosis in Patients without Manifest Cardiovascular Diseases: Never-ending Hope or Underestimated Effect? Molecules 2020; 25:molecules25071717. [PMID: 32283588 PMCID: PMC7181162 DOI: 10.3390/molecules25071717] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/03/2020] [Accepted: 04/07/2020] [Indexed: 12/21/2022] Open
Abstract
Micronutrients, especially vitamins, play an important role in the evolution of cardiovascular diseases (CVD). It has been speculated that additional intake of vitamins may reduce the CVD burden by acting on the inflammatory and oxidative response starting from early stages of atherosclerosis, when the vascular impairment might still be reversible or, at least, slowed down. The current review assesses the role of major vitamins on subclinical atherosclerosis process and the potential clinical implications in patients without CVD. We have comprehensively examined the literature data for the major vitamins: A, B group, C, D, and E, respectively. Most data are based on vitamin E, D and C supplementation, while vitamins A and B have been scarcely examined for the subclinical atherosclerosis action. Though the fundamental premise was optimistic, the up-to-date trials with vitamin supplementation revealed divergent results on subclinical atherosclerosis improvement, both in healthy subjects and patients with CVD, while the long-term effect seems minimal. Thus, there are no conclusive data on the prevention and progression of atherosclerosis based on vitamin supplementation. However, given their enormous potential, future trials are certainly needed for a more tailored CVD prevention focusing on early stages as subclinical atherosclerosis.
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Fatahi S, Pezeshki M, Mousavi SM, Teymouri A, Rahmani J, Kord Varkaneh H, Ghaedi E. Effects of folic acid supplementation on C-reactive protein: A systematic review and meta-analysis of randomized controlled trials. Nutr Metab Cardiovasc Dis 2019; 29:432-439. [PMID: 30940490 DOI: 10.1016/j.numecd.2018.11.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 11/18/2018] [Accepted: 11/22/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIM Given the contradictory results of previous randomized controlled trials (RCTs), we performed a systematic review and meta-analysis to quantify and summarize the effects of folic acid supplementation on C-reactive protein (CRP). METHODS AND RESULTS We performed a systematic search of all available RCTs conducted up to October 2018 in the following databases: PubMed, Scopus, and Cochrane. RCTs that investigated the effect of folate on CRP were included in the present study. Data were combined with the use of generic inverse-variance random-effects models. Statistical heterogeneity between studies was evaluated using Cochran's Q-test. Ten RCTs (1179 subjects) were included in the present meta-analysis. Pooled analysis results showed that folate supplementation significantly lowered the serum CRP level (weighted mean difference (WMD): -0.685 mg/l, 95% CI: -1.053, -0.318, p < 0.001). However, heterogeneity was significant (I2 = 96.7%, p = 0.000). Stratified analyses indicated that sex, intervention period, and type of study population were sources of heterogeneity. Following analysis, results revealed that the greatest impact was observed in women (WMD: -0.967 mg/l, 95% CI: -1.101, -0.833, p = 0.000), patients with type 2 diabetes mellitus (WMD: -1.764 mg/l, 95% CI: -2.002, -1.526, p = 0.000), and intervention period less than 12 weeks (WMD: -0.742 mg/l, 95% CI: -0.834, -0.650, p = 0.000). CONCLUSION This meta-analysis suggested that folic acid supplementation could significantly lower the serum CRP level. Folic acid leads to greater CRP lowering effect in women, patients with T2DM, and those with less than 12-week intervention.
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Affiliation(s)
- S Fatahi
- Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - M Pezeshki
- Pharmacy department Iran Drug and Poisons Information Center (DPIC), Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - S M Mousavi
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - A Teymouri
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - J Rahmani
- Student research committee, Department of Clinical Nutrition and dietetics, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - H Kord Varkaneh
- Student research committee, Department of Clinical Nutrition and dietetics, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - E Ghaedi
- Department of Cellular and molecular Nutrition, School of Nutritional sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
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Talari HR, Bahrami M, Ardestani AT, Bahmani F, Famili P, Asemi Z. Effects of Folate Supplementation on Carotid Intima-Media Thickness, Biomarkers of Inflammation, and Oxidative Stress in Carbamazepine-Treated Epileptic Children. Int J Prev Med 2019; 10:4. [PMID: 30774838 PMCID: PMC6360991 DOI: 10.4103/ijpvm.ijpvm_152_18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 11/02/2018] [Indexed: 11/05/2022] Open
Abstract
Background: This study was conducted to assess the effects of folate supplementation on carotid intima-media thickness (CIMT), biomarkers of inflammation, and oxidative stress in carbamazepine-treated epileptic children. Methods: This randomized, double-blind, placebo-controlled trial was carried out in 54 epileptic children aged 2–12 years old receiving carbamazepine monotherapy. Participants were randomly allocated into two groups to receive either 5 mg folate supplements or placebo (n = 27 in each group) for 12 weeks. Results: After the 12-week intervention, compared with the placebo, folate supplementation resulted in a significant reduction in plasma homocysteine (Hcy) (changes from baseline − 2.1 ± 2.5 vs. +0.1 ± 0.4 μmol/L, P < 0.001), serum high-sensitivity C-reactive protein (hs-CRP) (changes from baseline − 1.5 ± 3.5 vs. +0.4 ± 1.4 mg/L, P = 0.01), a significant increase in plasma nitric oxide (NO) (changes from baseline + 1.9 ± 5.8 vs. −2.0 ± 6.4 μmol/L, P = 0.02), and total antioxidant capacity (TAC) concentrations (changes from baseline + 88.6 ± 116.0 vs. +1.8 ± 77.4 mmol/L, P = 0.002). We did not observe any significant effects in mean levels of left and right CIMT, maximum levels of left and right CIMT, and total glutathione (GSH) and malondialdehyde (MDA) levels following the supplementation of folate compared with the placebo. Conclusions: Overall, folate supplementation at a dosage of 5 mg/day for 12 weeks among epileptic children receiving carbamazepine had beneficial effects on Hcy, hs-CRP, NO, and TAC levels, but did not affect CIMT, and GSH and MDA levels.
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Affiliation(s)
- Hamid Reza Talari
- Department of Radiology, Kashan University of Medical Sciences, Kashan, I.R. Iran
| | - Mansour Bahrami
- Department of Radiology, Kashan University of Medical Sciences, Kashan, I.R. Iran
| | - Ahmad Talebian Ardestani
- Department of Pediatrics, School of Medicine, Kashan University of Medical Sciences, Kashan, I.R. Iran
| | - Fereshteh Bahmani
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, I.R. Iran
| | - Peyman Famili
- Department of Radiology, Kashan University of Medical Sciences, Kashan, I.R. Iran
| | - Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, I.R. Iran
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Christen WG, Cook NR, Van Denburgh M, Zaharris E, Albert CM, Manson JE. Effect of Combined Treatment With Folic Acid, Vitamin B 6, and Vitamin B 12 on Plasma Biomarkers of Inflammation and Endothelial Dysfunction in Women. J Am Heart Assoc 2018; 7:e008517. [PMID: 29776960 PMCID: PMC6015379 DOI: 10.1161/jaha.117.008517] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 04/16/2018] [Indexed: 12/31/2022]
Abstract
BACKGROUND The aim of this study was to determine whether reducing plasma homocysteine concentrations with long-term, combined treatment with folic acid, vitamin B6, and vitamin B12 alters plasma biomarkers of inflammation and endothelial dysfunction in women at increased risk of cardiovascular disease. METHODS AND RESULTS We conducted a blood substudy of 300 treatment-adherent participants (150 in the active treatment group, 150 in the placebo group) in the WAFACS (Women's Antioxidant and Folic Acid Cardiovascular Study), a randomized, double-blind, placebo-controlled trial testing a daily combination of folic acid (2.5 mg), vitamin B6 (50 mg), vitamin B12 (1 mg), or matching placebo, in cardiovascular disease prevention among women at increased risk of cardiovascular disease. Plasma concentration of 3 biomarkers of inflammation (C-reactive protein, interleukin-6, and fibrinogen) and a biomarker of endothelial dysfunction (intercellular adhesion molecule 1) were measured at baseline and at the end of treatment and follow-up. After 7.3 years of combined treatment with folic acid, vitamin B6, and vitamin B12, homocysteine concentrations were reduced by 18% in the active treatment group as compared with the placebo group (P<0.001). However, there was no difference between treatment groups in change in blood concentration from baseline to follow-up for C-reactive protein (P=0.77), interleukin-6 (P=0.91), intercellular adhesion molecule 1 (P=0.38), or fibrinogen (P=0.68). CONCLUSIONS These findings indicate that long-term, combined treatment with folic acid, vitamin B6, and vitamin B12 lowers homocysteine concentrations, but does not alter major biomarkers of vascular inflammation, consistent with the lack of clinical cardiovascular disease benefit in the trial. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000541.
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Affiliation(s)
- William G Christen
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital Harvard Medical School, Boston, MA
| | - Nancy R Cook
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital Harvard Medical School, Boston, MA
- Department of Epidemiology, Harvard School of Public Health, Boston, MA
| | - Martin Van Denburgh
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital Harvard Medical School, Boston, MA
| | - Elaine Zaharris
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital Harvard Medical School, Boston, MA
| | - Christine M Albert
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital Harvard Medical School, Boston, MA
- Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital Harvard Medical School, Boston, MA
| | - JoAnn E Manson
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital Harvard Medical School, Boston, MA
- Department of Epidemiology, Harvard School of Public Health, Boston, MA
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13
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Hashemi M, Heshmat-Ghahdarijani K, Zarean E, Baktash F, Mortazavi ZS. Evaluation of the effect of high-dose folic acid on endothelial dysfunction in pre-eclamptic patients: A randomized clinical trial. JOURNAL OF RESEARCH IN MEDICAL SCIENCES 2016; 21:114. [PMID: 28255322 PMCID: PMC5331770 DOI: 10.4103/1735-1995.193505] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 07/16/2016] [Accepted: 08/14/2016] [Indexed: 12/17/2022]
Abstract
Background: Pre-eclampsia as a hypertensive disorder of pregnancy complicates up to 5–10% of pregnancies worldwide. Endothelial dysfunction plays an important role in the pathogenesis of pre-eclampsia. In this study, we aim to evaluate the effect of high-dose folic acid on endothelial dysfunction in pre-eclamptic patients. Materials and Methods: In this triple-blinded randomized clinical trial, the enrolled patients were divided randomly into two groups. Folic acid 5.0 mg or placebo was taken daily by oral administration from the initiation of diagnosis until 2 months after delivery by the participants. Every patient's flow-mediated dilation (FMD) was evaluated at the beginning of the study and 2 months after delivery with the same experienced operator at the same period of time (3–5 p.m.) by high-resolution B-mode ultrasonography. Potential confounding variables were included in the independent samples t-test. t-test or Mann–Whitney U-test was used in the comparison of means between the intervention and placebo groups. To compare FMD in each group, before and after the intervention, paired t-test was used. Results: Mean value of FMD in intervention (9.64 ± 5.57) and control group (9.30 ± 4.25) has no significant difference before the consumption of drugs (P > 0.05). FMD in intervention group (13.72 ± 7.89) significantly increases after daily consumption of 5 mg folic acid in comparison with control group (10.02 ± 4.81) after daily consumption of placebo (P = 0.002). Conclusion: Increased mean of FMD in intervention group shows that this supplement can improve endothelial function and can be significantly affected by maternal blood pressure during pregnancy and some endothelium-dependent disease such as pre-eclampsia and its associated adverse outcomes.
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Affiliation(s)
- Mohammad Hashemi
- Department of Cardiology, Isfahan University of Medical Sciences, Isfahan, Iran
| | | | - Elahe Zarean
- Department of Obstetrics-Gynecology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Forouz Baktash
- Department of Cardiology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Zahra Sadat Mortazavi
- Student Research Committee, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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Singh MD, Thomas P, Owens J, Hague W, Fenech M. Potential role of folate in pre-eclampsia. Nutr Rev 2015; 73:694-722. [PMID: 26359215 DOI: 10.1093/nutrit/nuv028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Dietary deficiencies of folate and other B vitamin cofactors involved in one-carbon metabolism, together with genetic polymorphisms in key folate-methionine metabolic pathway enzymes, are associated with increases in circulating plasma homocysteine, reduction in DNA methylation patterns, and genome instability events. All of these biomarkers have also been associated with pre-eclampsia. The aim of this review was to explore the literature and identify potential knowledge gaps in relation to the role of folate at the genomic level in either the etiology or the prevention of pre-eclampsia. A systematic search strategy was designed to identify citations in electronic databases for the following terms: folic acid supplementation AND pre-eclampsia, folic acid supplementation AND genome stability, folate AND genome stability AND pre-eclampsia, folic acid supplementation AND DNA methylation, and folate AND DNA methylation AND pre-eclampsia. Forty-three articles were selected according to predefined selection criteria. The studies included in the present review were not homogeneous, which made pooled analysis of the data very difficult. The present review highlights associations between folate deficiency and certain biomarkers observed in various tissues of women at risk of pre-eclampsia. Further investigation is required to understand the role of folate in either the etiology or the prevention of pre-eclampsia.
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Affiliation(s)
- Mansi Dass Singh
- M.D. Singh, J. Owens, and W. Hague are with the School of Pediatrics and Reproductive Health, Discipline of Obstetrics and Gynecology, Faculty of Health Sciences, Robinson Institute, Australian Research Centre for Health of Women and Babies, The University of Adelaide, Adelaide, South Australia, Australia. M.D. Singh, P. Thomas and M. Fenech are with the Genome Health and Personalized Nutrition Laboratory Commonwealth Scientific and Industrial Research Organization (CSIRO), Food and Nutrition Flagship, Adelaide, South Australia, Australia
| | - Philip Thomas
- M.D. Singh, J. Owens, and W. Hague are with the School of Pediatrics and Reproductive Health, Discipline of Obstetrics and Gynecology, Faculty of Health Sciences, Robinson Institute, Australian Research Centre for Health of Women and Babies, The University of Adelaide, Adelaide, South Australia, Australia. M.D. Singh, P. Thomas and M. Fenech are with the Genome Health and Personalized Nutrition Laboratory Commonwealth Scientific and Industrial Research Organization (CSIRO), Food and Nutrition Flagship, Adelaide, South Australia, Australia
| | - Julie Owens
- M.D. Singh, J. Owens, and W. Hague are with the School of Pediatrics and Reproductive Health, Discipline of Obstetrics and Gynecology, Faculty of Health Sciences, Robinson Institute, Australian Research Centre for Health of Women and Babies, The University of Adelaide, Adelaide, South Australia, Australia. M.D. Singh, P. Thomas and M. Fenech are with the Genome Health and Personalized Nutrition Laboratory Commonwealth Scientific and Industrial Research Organization (CSIRO), Food and Nutrition Flagship, Adelaide, South Australia, Australia
| | - William Hague
- M.D. Singh, J. Owens, and W. Hague are with the School of Pediatrics and Reproductive Health, Discipline of Obstetrics and Gynecology, Faculty of Health Sciences, Robinson Institute, Australian Research Centre for Health of Women and Babies, The University of Adelaide, Adelaide, South Australia, Australia. M.D. Singh, P. Thomas and M. Fenech are with the Genome Health and Personalized Nutrition Laboratory Commonwealth Scientific and Industrial Research Organization (CSIRO), Food and Nutrition Flagship, Adelaide, South Australia, Australia
| | - Michael Fenech
- M.D. Singh, J. Owens, and W. Hague are with the School of Pediatrics and Reproductive Health, Discipline of Obstetrics and Gynecology, Faculty of Health Sciences, Robinson Institute, Australian Research Centre for Health of Women and Babies, The University of Adelaide, Adelaide, South Australia, Australia. M.D. Singh, P. Thomas and M. Fenech are with the Genome Health and Personalized Nutrition Laboratory Commonwealth Scientific and Industrial Research Organization (CSIRO), Food and Nutrition Flagship, Adelaide, South Australia, Australia.
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15
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Grigoletti SS, Guindani G, Moraes RS, Ribeiro JP, Sprinz E. Short-term folinic acid supplementation improves vascular reactivity in HIV-infected individuals: a randomized trial. Nutrition 2014; 29:886-91. [PMID: 23660169 DOI: 10.1016/j.nut.2013.01.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2012] [Revised: 01/12/2013] [Accepted: 01/16/2013] [Indexed: 10/26/2022]
Abstract
OBJECTIVE HIV-infected individuals present a cluster of conditions that activate or injure the vascular endothelium. The administration of folates may exert beneficial effects on endothelial function in different populations at risk for cardiovascular disease. The aim of this study was to determine the effects of 4 wk of folinic acid supplementation on forearm vascular responses during reactive hyperemia in HIV-infected patients under highly active antiretroviral therapy. METHODS This was a prospective, randomized, double-blind, placebo-controlled trial to compare the effects of 4 wk of daily ingestion of 5 mg of folinic acid (n = 15) or placebo (n = 15). Participants had to have been on antiretroviral therapy (ART) for at least 6 mo before enrollment, with undetectable viral load, and CD4 cell count >200 cells/mm(3). Vascular function was evaluated with venous occlusion plethysmography at baseline and after 4 wk, for the determination of brachial artery reactive hyperemia, and after isosorbide dinitrate administration. RESULTS The groups were comparable. The mean age of patients was 45 y; there were eight women in each group. There was no difference regarding ART regimen. The supplementation of folinic acid produced a significant improvement in reactive hyperemia (from 14.9 to 21.2 mL•min•100 mL). The same was not observed in placebo group (from 15.3 to 14.6 mL•min•100 mL; group P, 0.017; time P < 0.001; interaction P < 0.001). Endothelium-independent responses remained unchanged. CONCLUSIONS Short-term folinic acid supplementation improved vascular reactivity in HIV-infected individuals enrolled in the studied. As folate supplementation is safe and relatively inexpensive, long-term clinical trials should be conducted.
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Affiliation(s)
- Shana S Grigoletti
- Exercise Pathophysiology Research Laboratory, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
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16
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Asemi Z, Samimi M, Tabassi Z, Shakeri H, Esmaillzadeh A. Vitamin D supplementation affects serum high-sensitivity C-reactive protein, insulin resistance, and biomarkers of oxidative stress in pregnant women. J Nutr 2013; 143:1432-8. [PMID: 23884390 DOI: 10.3945/jn.113.177550] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Unfavorable metabolic profiles and oxidative stress in pregnancy are associated with several complications. This study was conducted to determine the effects of vitamin D supplementation on serum concentrations of high-sensitivity C-reactive protein (hs-CRP), metabolic profiles, and biomarkers of oxidative stress in healthy pregnant women. This randomized, double-blind, placebo-controlled clinical trial was conducted in 48 pregnant women aged 18-40 y old at 25 wk of gestation. Participants were randomly assigned to receive either 400 IU/d cholecalciferol supplements (n = 24) or placebo (n = 24) for 9 wk. Fasting blood samples were taken at study baseline and after 9 wk of intervention to quantify serum concentrations of hs-CRP, lipid concentrations, insulin, and biomarkers of oxidative stress. After 9 wk of intervention, the increases in serum 25-hydroxyvitamin D and calcium concentrations were greater in the vitamin D group (+3.7 μg/L and +0.20 mg/dL, respectively) than in the placebo group (-1.2 μg/L and -0.12 mg/dL, respectively; P < 0.001 for both). Vitamin D supplementation resulted in a significant decrease in serum hs-CRP (vitamin D vs. placebo groups: -1.41 vs. +1.50 μg/mL; P-interaction = 0.01) and insulin concentrations (vitamin D vs. placebo groups: -1.0 vs. +2.6 μIU/mL; P-interaction = 0.04) and a significant increase in the Quantitative Insulin Sensitivity Check Index score (vitamin D vs. placebo groups: +0.02 vs. -0.02; P-interaction = 0.006), plasma total antioxidant capacity (vitamin D vs. placebo groups: +152 vs. -20 mmol/L; P-interaction = 0.002), and total glutathione concentrations (vitamin D vs. placebo groups: +205 vs. -32 μmol/L; P-interaction = 0.02) compared with placebo. Intake of vitamin D supplements led to a significant decrease in fasting plasma glucose (vitamin D vs. placebo groups: -0.65 vs. -0.12 mmol/L; P-interaction = 0.01), systolic blood pressure (vitamin D vs. placebo groups: -0.2 vs. +5.5 mm Hg; P-interaction = 0.01), and diastolic blood pressure (vitamin D vs. placebo groups: -0.4 vs. +3.1 mm Hg; P-interaction = 0.01) compared with placebo. In conclusion, vitamin D supplementation for 9 wk among pregnant women has beneficial effects on metabolic status.
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Affiliation(s)
- Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
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17
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Sun CH, Li Y, Zhang YB, Wang F, Zhou XL, Wang F. The effect of vitamin-mineral supplementation on CRP and IL-6: a systemic review and meta-analysis of randomised controlled trials. Nutr Metab Cardiovasc Dis 2011; 21:576-583. [PMID: 20399082 DOI: 10.1016/j.numecd.2009.12.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 12/07/2009] [Accepted: 12/29/2009] [Indexed: 11/15/2022]
Abstract
BACKGROUND AND AIMS Inflammation is regarded as a risk predictor for metabolic syndrome and atherogenesis. The objective of this study was to conduct a systematic review and a meta-analysis to confirm the effect of vitamin-mineral supplementation on cytokine levels. METHODS AND RESULTS We searched the PubMed, EMBASE and Cochrane databases up to May 2009 for randomised controlled trials regarding the effect of vitamin-mineral supplementation on C-reactive protein (CRP) and interleukin-6 (IL-6). Eighteen trials with 1747 participants for CRP and nine trials with 1037 participants for IL-6 were included, respectively. Pooled estimates and 95% confidence intervals (CIs) were calculated by fixed- or random-effects model. No significant differences were observed for CRP and IL-6 reduction between the subjects with vitamin-mineral supplementation and placebo control. A dose-dependent manner for different body mass index (BMI) subgroups in CRP analysis was observed (weighted mean difference (WMD), -0.057; 95%CI: -0.753 to 0.639 for BMI<25; WMD, -0.426; 95%CI: -0.930 to 0.079 for 25 ≤ BMI < 30; WMD, -0.491; 95%CI: -1.407 to 0.424 for BMI ≥ 30). However, no significance was detected in meta-regression (-0.046, 95%CI: -0.135 to 0.044). Moreover, the best effect for reduction in CRP levels in a supplementation duration of 4 weeks-6 months (WMD, -0.449; 95%CI: -1.004 to 0.106) was observed compared with supplementation duration less than 4 weeks (WMD, -0.137; 95%CI, -0.816 to 0.541) and more than 6 months (WMD, -0.389; 95%CI, -1.034 to 0.257) without statistical significance (P = 0.059). CONCLUSION No statistically significant evidences for the potential dose-dependent manner of BMI and best supplement duration were detected in this study. Large and well-designed studies are recommended to confirm this conclusion.
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Affiliation(s)
- C-H Sun
- Department of Nutrition and Food Hygiene, Public Health College, Harbin Medical University, Harbin, Heilongjiang Province, China.
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18
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Hoch AZ, Papanek P, Szabo A, Widlansky ME, Gutterman DD. Folic acid supplementation improves vascular function in professional dancers with endothelial dysfunction. PM R 2011; 3:1005-12. [PMID: 21715240 DOI: 10.1016/j.pmrj.2011.02.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 02/17/2011] [Accepted: 02/07/2011] [Indexed: 01/18/2023]
Abstract
OBJECTIVE To determine if folic acid supplementation improves vascular function (brachial artery flow-mediated dilation [FMD]) in professional dancers with known endothelial dysfunction. DESIGN Prospective cross-sectional study. SETTING Academic institution in the Midwestern United States. SUBJECTS Twenty-two professional ballet dancers volunteered for this study. MAIN OUTCOME MEASURES Subjects completed a 3-day food record to determine caloric and micronutrient intake. Menstrual status was determined by interview and questionnaire. Endothelial function was determined as flow-induced vasodilation measured by high-frequency ultrasound of the brachial artery. A change in brachial diameter of <5% to hyperemic flow stimulus was defined a priori as endothelial dysfunction. Subjects with abnormal FMD took 10 mg of folic acid daily for 4 weeks, and FMD testing was then repeated. Serum whole blood was measured for folic acid levels before and after supplementation. RESULTS Sixty-four percent of dancers (n = 14) had abnormal brachial artery FMD (<5%) (mean ± standard deviation, 2.9% ± 1.5%). After 4 weeks of folic acid supplementation (10 mg/day), FMD improved in all the subjects (7.1% ± 2.3%; P < .0001). CONCLUSIONS This study reveals that vascular endothelial function improves in dancers after supplementation with folic acid (10 mg/day) for at least 4 weeks. This finding may have clinically important implications for future cardiovascular disease risk prevention.
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Affiliation(s)
- Anne Z Hoch
- Department of Orthopaedic Surgery/Cardiovascular Center, Medical College of Wisconsin, Milwaukee, USA.
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19
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Abstract
In a previous issue of Annals of Medicine, we presented evidence in support of the concept that an abnormally increased production of reactive oxygen species plays a central role in the genesis and progression of cardiovascular disease. While a number of preclinical lines of evidence support this concept, and despite the results of many studies suggesting a beneficial impact of antioxidant drugs on endothelial function, large clinical trials have failed to demonstrate a benefit of antioxidants on cardiovascular outcomes. Studies exploring the possibility that classical antioxidants such as vitamin C, vitamin E, selenium, or folic acid may improve the prognosis of patients with cardiac disease have substantially reported neutral-and occasionally negative-results. In contrast, medications such as statins, ACE inhibitors, certain β-blockers, or angiotensin I receptor blockers, which possess indirect 'ancillary' antioxidant properties, have been associated with beneficial effects in both preclinical studies and large clinical trials. The reasons for the failure of the 'direct' approach to antioxidant therapy, and for the success of the therapy with these drugs, are discussed in the present review.
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Affiliation(s)
- Tommaso Gori
- II Medizinische Klinik für Kardiologie/Angiologie, University Medical Center of the Johannes Gutenberg University Mainz, Germany.
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20
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Abstract
OBJECTIVE The purpose of this study was to determine if folic acid supplementation improves endothelial vascular function (brachial artery flow-mediated dilation; FMD) in amenorrheic runners. DESIGN Prospective cross-sectional study. SETTING Academic medical center in the Midwest. PARTICIPANTS Ten amenorrheic and 10 eumenorrheic women runners from the community volunteered for this study. INTERVENTIONS Each participant was treated with folic acid (10 mg/d) for 4 weeks. MAIN OUTCOME MEASURES Brachial artery FMD was measured before and after folic acid supplementation with standard techniques. RESULTS The brachial artery FMD response to reactive hyperemia improved after folic acid supplementation in amenorrheic women (3.0% +/- 2.3% vs. 7.7% +/- 4.5%; P = 0.02). In the eumenorrheic control group, there was no change in brachial artery FMD (6.7% +/- 2.0% vs. 5.9% +/- 2.6%; P = 0.52). CONCLUSIONS This study demonstrates that brachial artery FMD, an indicator of vascular endothelial function, improves in amenorrheic female runners after short-term supplementation with folic acid.
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Ho GYF, Xue X, Cushman M, McKeown-Eyssen G, Sandler RS, Ahnen DJ, Barry EL, Saibil F, Bresalier RS, Rohan TE, Baron JA. Antagonistic effects of aspirin and folic acid on inflammation markers and subsequent risk of recurrent colorectal adenomas. J Natl Cancer Inst 2009; 101:1650-4. [PMID: 19822838 DOI: 10.1093/jnci/djp346] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The Aspirin/Folate Polyp Prevention Trial found that aspirin, but not folic acid, reduced recurrence of colorectal adenomas. This study examined whether treatment effects on inflammation markers explained the trial results. The trial had a factorial design with three aspirin (placebo, 81, and 325 mg/d) and two folic acid (placebo and 1 mg/d) groups. There were 884 subjects who had colonoscopic evaluation for adenomas at year 3 and plasma levels of C-reactive protein (CRP), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), soluble TNF receptor type II (sTNF-R2), and IL-1 receptor antagonist (IL-1Ra) measured at baseline and year 3. Among individuals not receiving folic acid, there was a 4% decrease (mean ratio of year 3 to baseline levels = 0.96, 95% confidence interval [CI] = 0.82 to 1.14) in CRP for a period of 3 years in the 325 mg of aspirin group vs a 20% increase (mean ratio = 1.20, 95% CI = 1.03 to 1.41) in the placebo group (P = .027). By contrast, the reverse was observed among individuals who also received folic acid (P(interaction) = .013). Changes in inflammation markers were not associated with adenoma recurrence. Low-dose aspirin (325 mg/d) is beneficial in stabilizing CRP levels, which may be abrogated by folate. Nevertheless, inflammation markers do not mediate the chemopreventive effect of aspirin on colorectal adenomas.
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Affiliation(s)
- Gloria Y F Ho
- Department of Epidemiology & Population Health, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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van Guelpen B. Folate in colorectal cancer, prostate cancer and cardiovascular disease. Scandinavian Journal of Clinical and Laboratory Investigation 2009; 67:459-73. [PMID: 17763182 DOI: 10.1080/00365510601161513] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- B van Guelpen
- Department of Medical Biosciences, Pathology, Umeå University, Umeå, Sweden.
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Moens AL, Vrints CJ, Claeys MJ, Timmermans JP, Champion HC, Kass DA. Mechanisms and potential therapeutic targets for folic acid in cardiovascular disease. Am J Physiol Heart Circ Physiol 2008; 294:H1971-7. [PMID: 18375715 DOI: 10.1152/ajpheart.91503.2007] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Folic acid (FA) is a member of the B-vitamin family with cardiovascular roles in homocysteine regulation and endothelial nitric oxide synthase (eNOS) activity. Its interaction with eNOS is thought to be due to the enhancement of tetrahydrobiopterin bioavailability, helping maintain eNOS in its coupled state to favor the generation of nitric oxide rather than oxygen free radicals. FA also plays a role in the prevention of several cardiac and noncardiac malformations, has potent direct antioxidant and antithrombotic effects, and can interfere with the production of the endothelial-derived hyperpolarizing factor. These multiple mechanisms of action have led to studies regarding the therapeutic potential of FA in cardiovascular disease. To date, studies have demonstrated that FA ameliorates endothelial dysfunction and nitrate tolerance and can improve pathological features of atherosclerosis. These effects appear to be homocysteine independent but rather related to their role in eNOS function. Given the growing evidence that nitric oxide synthase uncoupling plays a major role in many cardiovascular disorders, the potential of exogenous FA as an inexpensive and safe oral therapy is intriguing and is stimulating ongoing investigations.
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Affiliation(s)
- An L Moens
- Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, MD, USA.
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25
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Steffen LM, Folsom AR, Cushman M, Jacobs DR, Rosamond WD. Greater Fish, Fruit, and Vegetable Intakes Are Related to Lower Incidence of Venous Thromboembolism. Circulation 2007; 115:188-95. [PMID: 17179018 DOI: 10.1161/circulationaha.106.641688] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Background—
Little is known about the role of dietary intake in the development of deep vein thrombosis or pulmonary embolus (venous thromboembolism [VTE]). Homocysteine, factor VIII, and von Willebrand factor levels, risk factors for VTE, are influenced by dietary intake. We tested the hypothesis that foods rich in B vitamins and ω-3 fatty acids are negatively associated and meat intake is positively associated with incidence of VTE.
Methods and Results—
In a prospective study over 12 years, 14 962 middle-aged adults participating in the Atherosclerosis Risk in Communities study were followed up for incident VTE. All hospitalizations were identified, and 196 VTEs were validated by chart review. A food frequency questionnaire assessed dietary intake at baseline and year 6. In separate proportional hazards regression analyses, risk of developing VTE was computed across quintiles of selected nutrients, major food groups, and the Western diet pattern, with adjustment for demographic and lifestyle factors, body mass index, and diabetes. Hazard ratios and 95% confidence intervals of VTE incidence across quintiles of fruit and vegetable intake were 1.0 (reference), 0.73 (0.48 to 1.11), 0.57 (0.37 to 0.90), 0.47 (0.29 to 0.77), and 0.59 (0.36 to 0.99) (
P
trend
=0.03). Eating fish 1 or more times per week was associated with 30% to 45% lower incidence of VTE for quintiles 2 to 5 compared with quintile 1, suggestive of a threshold effect. Hazard ratios of VTE across quintiles of red and processed meat intake were 1.0, 1.24 (0.78 to 1.98), 1.21 (0.74 to 1.98), 1.09 (0.64 to 1.87), and 2.01 (1.15 to 3.53) (
P
trend
=0.02). Hazard ratios were attenuated only slightly after adjustment for factors VIIc and VIIIc and von Willebrand factor.
Conclusions—
A diet including more plant food and fish and less red and processed meat is associated with a lower incidence of VTE.
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Affiliation(s)
- Lyn M Steffen
- Division of Epidemiology and Community Health, University of Minnesota School of Public Health, 1300 S Second St, Suite 300, Minneapolis, MN 55454, USA.
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Stricker H, Colucci G, Mombelli G. Acute effect of smoking and of 2 weeks of folate substitution on hemostasis and homocysteine in healthy chronic smokers. J Thromb Haemost 2006; 4:2500-3. [PMID: 17059475 DOI: 10.1111/j.1538-7836.2006.02189.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pathansali R, Mangoni AA, Creagh-Brown B, Lan ZC, Ngow GL, Yuan XF, Ouldred EL, Sherwood RA, Swift CG, Jackson SHD. Effects of folic acid supplementation on psychomotor performance and hemorheology in healthy elderly subjects. Arch Gerontol Geriatr 2006; 43:127-37. [PMID: 16359741 DOI: 10.1016/j.archger.2005.10.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2005] [Revised: 10/10/2005] [Accepted: 10/14/2005] [Indexed: 11/18/2022]
Abstract
Cognitive impairment is associated with increased blood concentrations of homocysteine and high blood viscosity. Previous studies have shown that vitamin B supplementation reduces homocysteine and enhances cognitive function in patients with mild dementia and low serum folic acid. However, whether folic acid enhances cognitive function in elderly subjects without dementia and normal serum folic acid is unknown. Twenty-four healthy elderly subjects (age 73.0+/-5.6 years, mean+/-S.D.) with normal serum folic acid (6.3+/-2.4 microg/l) and Mini Mental State Examination (MMSE) >27/30 were randomized to 4-week treatment with folic acid 5mg/day or placebo in a randomized, placebo-controlled, parallel-group study. Continuous Attention Test (CAT), Four-Choice Reaction Time (FCRT), Digit-Symbol Substitution (DSS), Scanning Memory Sets (SMS), and blood viscosity for different shear rates were measured before and after treatment. Folic acid supplementation induced a significant increase in serum folic acid levels (+13.8 versus +1.6 microg/l, p<0.001) and fall in homocysteine levels (-1.91 versus -0.41 micromol/l, p=0.05) compared to placebo. However, there was no significant change in CAT, FCRT, DSS, SMS, and blood viscosity between the two groups. Short-term folic acid supplementation does not enhance psychomotor performance or reduce blood viscosity in healthy elderly subjects with normal serum folic acid levels and preserved cognitive function.
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Affiliation(s)
- Rohan Pathansali
- Department of Health Care of the Elderly, Guy's, King's and St Thomas' School of Medicine, King's College London, London SE5 9PJ, UK
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28
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Bamonti F, Novembrino C, Ippolito S, Soresi E, Ciani A, Lonati S, Scurati-Manzoni E, Cighetti G. Increased free malondialdehyde concentrations in smokers normalise with a mixed fruit and vegetable juice concentrate: a pilot study. Clin Chem Lab Med 2006; 44:391-5. [PMID: 16599830 DOI: 10.1515/cclm.2006.084] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Cigarette smoking, a cardiovascular risk factor leading to oxygen free radical formation, is involved in the development of serious pathological conditions. On the other hand, a healthy diet and adequate supplementation can help prevent many diseases. The aim of our study was to evaluate in healthy light smokers the effects of supplementation with mixed fruit and vegetable juice powder concentrate on homocysteine metabolism and oxidative status. METHODS In this pilot study, 32 healthy volunteers, 16 light smokers and 16 non-smokers, on twice daily supplementation were monitored at time zero and after 30 days. Plasma homocysteine, and serum vitamin B(12) and folate concentrations were measured by immunoenzymatic assays; reactive oxygen species, total antioxidant capacity and thiol groups by spectrophotometric methods; and total and free malondialdehyde concentrations by gas chromatography-mass spectrometry with isotopic dilution. RESULTS Baseline free malondialdehyde concentrations were significantly higher in smokers than in non-smokers and normalised after 30-day supplementation. Baseline results for all the other parameters remained unchanged after supplementation, with no significant differences between smokers and non-smokers. CONCLUSION This is the first study showing a significant decrease in free malondialdehyde levels in light smokers after 1-month phytonutrient supplementation.
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Affiliation(s)
- Fabrizia Bamonti
- Department of Medical Science, University of Milan, Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Fondazione IRCCS, Milan, Italy.
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Young JM, Shand BI, McGregor PM, Scott RS, Frampton CM. Comparative effects of enzogenol and vitamin C supplementation versus vitamin C alone on endothelial function and biochemical markers of oxidative stress and inflammation in chronic smokers. Free Radic Res 2006; 40:85-94. [PMID: 16298763 DOI: 10.1080/10715760500329788] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Chronic smoking is associated with endothelial dysfunction and inflammation, with oxidative stress contributing to both these processes. In this study, we investigated the effect of combined antioxidant treatment with Enzogenol, a flavonoid extract from the bark of Pinus radiata and vitamin C, over and above vitamin C alone, on endothelial function, plasma markers of inflammation and oxidative stress, blood pressure (BP) and anthropometrics. Forty-four chronic smokers without established cardiovascular disease were assigned randomly to receive either 480 mg Enzogenol and 60 mg vitamin C, or 60 mg vitamin C alone daily for 12 weeks. Endothelial function in the brachial artery was assessed by flow-mediated vasodilation (FMD). FMD improved in both treatment groups (p < 0.001), with no significant difference between the two groups (p = 0.84). In the group receiving Enzogenol and vitamin C, protein carbonyl levels were significantly reduced compared to the group taking vitamin C alone (p = 0.03). Enzogenol and vitamin C resulted in a significant reduction in fibrinogen levels in heavy smokers compared with vitamin C alone (p < 0.009). These findings demonstrated that co-supplementation with Enzogenol and vitamin C in smokers conferred no additional beneficial effect on macrovascular endothelial function over and above that seen in the vitamin C alone group. However, Enzogenol did demonstrate additional favourable effects on protein oxidative damage and fibrinogen levels.
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Affiliation(s)
- Joanna M Young
- Lipid and Diabetes Research Group, Christchurch Hospital, New Zealand.
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30
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Mangoni AA. Folic acid, inflammation, and atherosclerosis: False hopes or the need for better trials? Clin Chim Acta 2006; 367:11-9. [PMID: 16413521 DOI: 10.1016/j.cca.2005.11.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2005] [Revised: 11/15/2005] [Accepted: 11/16/2005] [Indexed: 10/25/2022]
Abstract
An increasing body of evidence supports the existence of a strong link between inflammation, endothelial dysfunction, and the onset and progression of atherosclerosis. However, a cause-effect relationship between these phenomena has not been demonstrated yet. Although some inflammatory markers, such as C-reactive protein, have been recently shown to improve risk stratification and to strongly predict cardiovascular outcome, it is largely unknown whether modifications of these markers might provide salutary effects and reduce cardiovascular morbidity and mortality. The B-vitamin folic acid has recently gained attention because of its potential to provide beneficial effects on surrogate end-points, such as endothelial function, in patients at high cardiovascular risk. However, the role of folic acid in mitigating the pro-inflammatory state associated with atherosclerosis is controversial. Despite the theoretical arguments supporting the potential anti-atherosclerotic and anti-inflammatory effects of folic acid, the current evidence is limited, deriving from small trials on different study populations, using folic acid often in combination with other vitamins and for different treatment periods. This review will consider the current evidence supporting the role of some well-established inflammatory markers in predicting cardiovascular outcomes, the mechanisms by which folic acid might exert anti-inflammatory effects, the epidemiological data relating folic acid concentrations with inflammatory markers, the published interventional studies on the effects of folic acid supplementation on these markers, and the factors that need to be considered in designing future trials.
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Affiliation(s)
- Arduino A Mangoni
- Department of Clinical Pharmacology and Centre for Neuroscience, School of Medicine, Flinders University, GPO Box 2100, Adelaide 5001, Australia.
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Speidl WS, Nikfardjam M, Niessner A, Zeiner A, Jordanova N, Zorn G, Maurer G, Schreiber W, Wojta J, Huber K. Mild hyperhomocysteinemia is associated with a decreased fibrinolytic activity in patients after ST-elevation myocardial infarction. Thromb Res 2006; 119:331-6. [PMID: 16616324 DOI: 10.1016/j.thromres.2006.02.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2005] [Revised: 01/30/2006] [Accepted: 02/22/2006] [Indexed: 11/15/2022]
Abstract
BACKGROUND Elevated homocysteine (Hcy) levels have been associated with increased risk for cardiovascular disease and it has been shown that hyperhomocysteinemia is associated with increased levels of t-PA antigen in individuals without evidence for coronary artery disease (CAD). The aim of this study was to examine if Hcy plasma levels are associated with plasma levels of fibrinolytic factors in patients with CAD and a history of acute myocardial infarction. METHODS We measured in 56 patients with CAD, 1 month after their first ST-elevation myocardial infarction, plasma levels of Hcy, the fibrinolytic parameters tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-type-1 (PAI-1), and t-PA-PAI-1 complexes. RESULTS Hcy plasma levels inversely correlated with t-PA activity (r=-0.303, p<0.05). Patients with mild hyperhomocysteinemia (Hcy>15 micromol/L, n=8) showed significantly lower plasma levels of t-PA activity (p<0.05). Regression analysis revealed that out of cardiovascular risk factors and medical treatment only Hcy was significantly associated with t-PA activity. CONCLUSIONS Patients with CAD after a first myocardial infarction and hyperhomocysteinemia show a reduced t-PA activity independently from cardiovascular risk factors and medical treatment. Homocysteine lowering therapies may increase fibrinolytic activity and thereby may help to avoid atherothrombotic events in patients with CAD after a first myocardial infarction.
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Affiliation(s)
- Walter Stefan Speidl
- Department of Internal Medicine II, Medical University of Vienna and the Ludwig Boltzman Foundation for Cardiovascular Research, Austria
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Goldwasser P, Feldman JG, Emiru M, Barth RH. Effect of dialysis modality on plasma fibrinogen concentration: A meta-analysis. Am J Kidney Dis 2004; 44:941-9. [PMID: 15558516 DOI: 10.1053/j.ajkd.2004.08.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Concentrations of plasma fibrinogen, a vascular risk factor, tend to be greater in patients on peritoneal dialysis (PD) than hemodialysis (HD) therapy, like concentrations of serum cholesterol, lipoprotein(a), and transthyretin, despite the substantial loss of protein during PD. Worse vascular outcome has been noted in PD patients compared with HD patients in several studies. METHODS In this study, the mean difference in plasma fibrinogen levels (PD-HD) was quantified by means of meta-analysis of mean differences found in 12 cohorts with both PD and HD patients (set 1; N = 630) by using a fixed-effects model and meta-analysis of mean fibrinogen values reported in 30 cohorts of patients on a single dialysis modality (set 2; 8 PD cohorts, 22 HD cohorts; N = 2,096) by using a mixed model. RESULTS On meta-analysis, the weighted mean difference (PD-HD) was 105 mg/dL (95% confidence interval [CI], 86 to 124 [3.1 micromol/L; 95% CI, 2.5 to 3.6]) in set 1 and 103 mg/dL (95% CI, 53 to 153 [3.0 micromol/L; 95% CI, 1.6 to 4.5) in set 2. CONCLUSION Like other vascular risk factors, such as cholesterol and lipoprotein(a), plasma fibrinogen level is markedly greater in PD than HD patients, with an approximate difference of 100 mg/dL [2.9 mumol/L]. Different plasma reference ranges for fibrinogen need to be defined for PD and HD patients. The mechanism for the difference and the possible role of hyperfibrinogenemia in worsening vascular disease in PD patients deserve study.
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Affiliation(s)
- Philip Goldwasser
- Department of Medicine, Veterans Affairs New York Harbor Healthcare Center, Brooklyn, NY 11209, USA.
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