1
|
Deng Z, Li L. Effect of miR-663 on atherosclerosis by regulating the proliferation of vascular smooth muscle cells in lipid plaques. Vascular 2023; 31:1240-1252. [PMID: 35599617 DOI: 10.1177/17085381221098826] [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] [Indexed: 11/16/2022]
Abstract
OBJECTIVES Atherosclerosis (AS) is the main cause of coronary heart disease, cerebral infarction, and peripheral vascular disease. microRNAs (miRNAs) are widely distributed in the human body and closely related to the pathological progress of AS. This study probed into the function of miR-663 in AS. METHODS The atherosclerotic plaques, cholesterol (CHOL), low-density lipoprotein (LDL), inflammatory factors, and miR-663 expression in ApoE-/- mice on high-fat diet were evaluated. The overexpressing miR-663 adenovirus was injected into ApoE-/- mice, followed by measurement of type III collagen (Col III), matrix metalloproteinase (MMP)-2, α-SMA, osteopontin, and CD31. miR-663 mimic or inhibitor was introduced into vascular smooth muscle cells (VSMCs) stimulated by oxidized LDL (Ox-LDL), and cell proliferation and IL-6 and IL-18 secretion were evaluated. The binding relationship between miR-663 and HMGA2 was verified, followed by the determination of HMGA2 role in VSMC proliferation. RESULTS Atherosclerotic plaques appeared in ApoE-/- mice on high-fat diet, with increased CHOL, LDL, osteopontin, MMP-2 and Col III and decreased miR-663, α-SMA and CD31. miR-663 overexpression downregulated osteopontin, MMP-2 and Col III and upregulated α-SMA and CD31 in ApoE-/- mice on high-fat diet. With Ox-LDL concentration increase, VSMC proliferation was promoted and miR-663 was downregulated. miR-663 overexpression inhibited proliferation of Ox-LDL-stimulated VSMCs and reduced levels of inflammatory factor levels, whereas silencing miR-663 did the opposite. miR-663 targeted HMGA2. HMGA2 overexpression partially reversed the inhibitory effect of miR-663 overexpression on VSMC proliferation. CONCLUSION miR-663 targeted HMGA2 to inhibit VSMC proliferation and AS development, which may offer insights into AS treatment.
Collapse
Affiliation(s)
- Zhisheng Deng
- Department of Geriatrics, Nanchang Hospital Sun Yat-Sen University (The First Hospital of Nanchang), Nanchang, China
| | - Lihua Li
- Department of Geriatrics, Nanchang Hospital Sun Yat-Sen University (The First Hospital of Nanchang), Nanchang, China
| |
Collapse
|
2
|
Mason SA, Parker L, van der Pligt P, Wadley GD. Vitamin C supplementation for diabetes management: A comprehensive narrative review. Free Radic Biol Med 2023; 194:255-283. [PMID: 36526243 DOI: 10.1016/j.freeradbiomed.2022.12.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 12/01/2022] [Accepted: 12/05/2022] [Indexed: 12/15/2022]
Abstract
Growing evidence suggests that vitamin C supplementation may be an effective adjunct therapy in the management of people with diabetes. This paper critically reviews the current evidence on effects of vitamin C supplementation and its potential mechanisms in diabetes management. Evidence from meta-analyses of randomized controlled trials (RCTs) show favourable effects of vitamin C on glycaemic control and blood pressure that may be clinically meaningful, and mixed effects on blood lipids and endothelial function. However, evidence is mostly of low evidence certainty. Emerging evidence is promising for effects of vitamin C supplementation on some diabetes complications, particularly diabetic foot ulcers. However, there is a notable lack of robust and well-designed studies exploring effects of vitamin C as a single compound supplement on diabetes prevention and patient-important outcomes (i.e. prevention and amelioration of diabetes complications). RCTs are also required to investigate potential preventative or ameliorative effects of vitamin C on gestational diabetes outcomes. Oral vitamin C doses of 500-1000 mg per day are potentially effective, safe, and affordable for many individuals with diabetes. However, personalisation of supplementation regimens that consider factors such as vitamin C status, disease status, current glycaemic control, vitamin C intake, redox status, and genotype is important to optimize vitamin C's therapeutic effects safely. Finally, given a high prevalence of vitamin C deficiency in patients with complications, it is recommended that plasma vitamin C concentration be measured and monitored in the clinic setting.
Collapse
Affiliation(s)
- Shaun A Mason
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia.
| | - Lewan Parker
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia
| | - Paige van der Pligt
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia; Department of Nutrition and Dietetics, Western Health, Footscray, Australia
| | - Glenn D Wadley
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia
| |
Collapse
|
3
|
Le Master E, Ahn SJ, Levitan I. Mechanisms of endothelial stiffening in dyslipidemia and aging: Oxidized lipids and shear stress. CURRENT TOPICS IN MEMBRANES 2020; 86:185-215. [PMID: 33837693 PMCID: PMC8168803 DOI: 10.1016/bs.ctm.2020.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Vascular stiffening of the arterial walls is well-known as a key factor in aging and the development of cardiovascular disease; however, the role of endothelial stiffness in vascular dysfunction is still an emerging topic. In this review, the authors discuss the impact of dyslipidemia, oxidized lipids, substrate stiffness, age and pro-atherogenic disturbed flow have on endothelial stiffness. Furthermore, we investigate several mechanistic pathways that are key contributors in endothelial stiffness and discuss their physiological effects in the onset of atherogenesis in the disturbed flow regions of the aortic vasculature. The findings in this chapter describe a novel paradigm of synergistic interaction of plasma dyslipidemia/oxidized lipids and pro-atherogenic disturbed shear stress, as well as aging has on endothelial stiffness and vascular dysfunction.
Collapse
Affiliation(s)
- Elizabeth Le Master
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Sang Joon Ahn
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Irena Levitan
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, University of Illinois at Chicago, Chicago, IL, United States.
| |
Collapse
|
4
|
Travica N, Ried K, Hudson I, Sali A, Scholey A, Pipingas A. The Contribution of Plasma and Brain Vitamin C on Age and Gender-Related Cognitive Differences: A Mini-Review of the Literature. Front Integr Neurosci 2020; 14:47. [PMID: 32973470 PMCID: PMC7471743 DOI: 10.3389/fnint.2020.00047] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 07/24/2020] [Indexed: 12/14/2022] Open
Abstract
There is increasing evidence that sex differences in the brain may contribute to gender-related behavioral differences, including cognitive function. Literature has revealed gender dimorphisms in cognitive function between males and females. Additionally, several risk factors associated with cognitive decline depend on chronological age. It is well recognized that the process of aging is associated with a decline in cognitive ability and brain function. Various explanations may account for these gender-related cognitive differences and age-associated cognitive changes. Recent investigations have highlighted the importance of vitamin C in maintaining brain health and its association with cognitive function in both cognitively intact and impaired cohorts. The present review explores previous literature that has evaluated differences in plasma/brain vitamin C between genders and during aging. It then assesses whether these age and gender-related differences may affect the relationship between plasma/brain vitamin C and cognition. The purpose of this review was to examine the evidence for a link between plasma/brain vitamin C and cognition and the impact of gender and age on this relationship. Epidemiological studies have frequently shown higher vitamin C plasma concentrations in women. Similarly, aging has been systematically associated with reductions in plasma vitamin C levels. A range of animal studies has demonstrated potential gender and age-related differences in vitamin C brain distribution and utilization. The reviewed literature suggests that gender differences in plasma and brain vitamin C may potentially contribute to differences in gender-associated cognitive ability, particularly while females are pre-menopausal. Additionally, we can propose that age-associated differences in plasma and brain vitamin C may be potentially linked to age-associated cognitive differences, with older cohorts appearing more vulnerable to experience declines in plasma vitamin C concentrations alongside compromised vitamin C brain regulation. This review encourages future investigations to take into account both gender and age when assessing the link between plasma vitamin C concentrations and cognitive function. Further large scale investigations are required to assess whether differences in cognitive function between genders and age groups may be causally attributed to plasma vitamin C status and brain distribution and utilization.
Collapse
Affiliation(s)
- Nikolaj Travica
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
- The National Institute of Integrative Medicine, Melbourne, VIC, Australia
| | - Karin Ried
- The National Institute of Integrative Medicine, Melbourne, VIC, Australia
- Discipline of General Practice, University of Adelaide, Adelaide, SA, Australia
- Torrens University, Melbourne, VIC, Australia
| | - Irene Hudson
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
- School of Science, College of Science, Engineering and Health, Mathematical Sciences, Royal Melbourne Institute of Technology (RMIT), Melbourne, VIC, Australia
- School of Mathematical and Physical Science, University of Newcastle, Callaghan, NSW, Australia
| | - Avni Sali
- The National Institute of Integrative Medicine, Melbourne, VIC, Australia
| | - Andrew Scholey
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Andrew Pipingas
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
| |
Collapse
|
5
|
Protection of natural antioxidants against low-density lipoprotein oxidation. ADVANCES IN FOOD AND NUTRITION RESEARCH 2020. [PMID: 32711864 DOI: 10.1016/bs.afnr.2020.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
This chapter reports essential information about the protective action of antioxidants against LDL oxidation. The activity of individual compounds (tocopherols, vitamin C, phenolic compounds) as well as extracts obtained from plant material (cereals, fruits, legumes, nuts, mushrooms, by-products of food industry) is reported. The structure-antioxidant activity relationship of phenolic compounds is discussed. This article summarizes the findings to date of both in vitro and in vivo studies using foods or phenolic extracts isolated from foodstuffs at inhibiting the incidence of LDL oxidation. This chapter summarizes also the reportings to date of in vivo studies using foods or beverages at inhibiting the incidence of LDL oxidation.
Collapse
|
6
|
Silva T, Jäger W, Neuss-Radu M, Sequeira A. Modeling of the early stage of atherosclerosis with emphasis on the regulation of the endothelial permeability. J Theor Biol 2020; 496:110229. [PMID: 32259543 DOI: 10.1016/j.jtbi.2020.110229] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 02/25/2020] [Accepted: 02/29/2020] [Indexed: 02/03/2023]
Abstract
In this paper, we develop a mathematical model for the early stage of atherosclerosis, as a chronic inflammatory disease. It includes also processes that are relevant for the "thickening" of the vessel walls, and prepares a more complete model including also the later stages of atherosclerosis. The model consists of partial differential equations: Navier-Stokes equations modeling blood flow, Biot equations modeling the fluid flow inside the poroelastic vessel wall, and convection/chemotaxis-reaction-diffusion equations modeling transport, signaling and interaction processes initiating inflammation and atherosclerosis. The main innovations of this model are: a) quantifying the endothelial permeability to low-density-lipoproteins (LDL) and to the monocytes as a function of WSS, cytokines and LDL on the endothelial surface; b) transport of monocytes on the endothelial surface, mimicking the monocytes adhesion and rolling; c) the monocytes influx in the lumen, as a function of factor increasing monocytopoiesis; d) coupling between Navier-Stokes system, Biot system and convection/chemotaxis-reaction-diffusion equations. Numerical simulations of a simplified model were performed in an idealized two-dimensional geometry in order to investigate the dynamics of endothelial permeability, and the growth and spread of immune cells populations and their dependence in particular on low-density-lipoprotein and wall-shear stress.
Collapse
Affiliation(s)
- Telma Silva
- Mathematics Department and CEMAT, IST, University of Lisbon, Portugal.
| | - Willi Jäger
- IWR, University of Heidelberg, Heidelberg, Germany.
| | - Maria Neuss-Radu
- Mathematics Department, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
| | - Adélia Sequeira
- Mathematics Department and CEMAT, IST, University of Lisbon, Portugal.
| |
Collapse
|
7
|
Travica N, Ried K, Hudson I, Sali A, Scholey A, Pipingas A. Gender Differences in Plasma Vitamin C Concentrations and Cognitive Function: A Pilot Cross-Sectional Study in Healthy Adults. Curr Dev Nutr 2020; 4:nzaa038. [PMID: 32337476 PMCID: PMC7170048 DOI: 10.1093/cdn/nzaa038] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 03/03/2020] [Accepted: 03/09/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND A number of investigations have highlighted the importance of vitamin C in maintaining brain health. Biologically, vitamin C has exhibited roles in neuromodulation, neurodevelopment, vascular support, and neuroprotection. Vitamin C's contribution to cognitive function in both cognitively intact and impaired cohorts has previously been assessed, with little focus on gender variability. OBJECTIVE The present study explored the interaction between gender and plasma vitamin C on cognitive performance, and the effect of different amounts of plasma vitamin C (adequate/inadequate) on various cognitive tasks by gender. METHODS This retrospective analysis was conducted in healthy adults (n = 80, female = 52, male = 28, 24-96 y) with a range of blood plasma vitamin C concentrations. Cognitive assessments included the Swinburne University Computerized Cognitive Assessment Battery (SUCCAB) and 2 pen-and-paper tests, the Symbol Digits Modalities Test (SDMT) and the Hopkins Verbal Learning Test-Revised (HVLT-R). Food-frequency questionnaires were used to elucidate dietary consumption. RESULTS After adjusting for a number of potential covariates such as age, number of prescribed medications and dose of vitamin C supplementation, results indicated a significant interaction (P < 0.001) between plasma vitamin C and gender on cognitive function, on both the computerized and pen-and-paper assessments. A novel finding was that the performance of males with inadequate plasma vitamin C was poorer on tasks involving components of memory (short/delayed), inhibition, and visual perception, whereas females presenting with inadequate vitamin C were more compromised on tasks involving psychomotor performance/motor speed. Additionally, females with adequate vitamin C concentrations exhibited higher performance than males on tasks involving recall, recognition, attention, and focus. CONCLUSIONS Further larger-scale investigations are required to establish a cause-and-effect relation and to elucidate whether differences in cognitive function between genders may be attributed to plasma vitamin C status.This trial was registered at https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=369440&isReview=true as ACTRN12615001140549.
Collapse
Affiliation(s)
- Nikolaj Travica
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, Australia
- The National Institute of Integrative Medicine, Melbourne, Australia
| | - Karin Ried
- The National Institute of Integrative Medicine, Melbourne, Australia
- Discipline of General Practice, University of Adelaide, South Australia, Australia
- Torrens University, Melbourne, Australia
| | - Irene Hudson
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, Australia
- School of Science, College of Science, Engineering, and Health, Mathematical Sciences, Royal Melbourne Institute of Technology, Melbourne, Australia
- School of Mathematical and Physical Science, University of Newcastle, Newcastle, Australia
| | - Avni Sali
- The National Institute of Integrative Medicine, Melbourne, Australia
| | - Andrew Scholey
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, Australia
| | - Andrew Pipingas
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, Australia
| |
Collapse
|
8
|
Lee CH, Chan RSM, Wan HYL, Woo YC, Cheung CYY, Fong CHY, Cheung BMY, Lam TH, Janus E, Woo J, Lam KSL. Dietary Intake of Anti-Oxidant Vitamins A, C, and E Is Inversely Associated with Adverse Cardiovascular Outcomes in Chinese-A 22-Years Population-Based Prospective Study. Nutrients 2018; 10:nu10111664. [PMID: 30400367 PMCID: PMC6265686 DOI: 10.3390/nu10111664] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/12/2018] [Accepted: 10/24/2018] [Indexed: 12/03/2022] Open
Abstract
Background: Conflicting and population-dependent findings have been reported from epidemiological studies on the associations of dietary intake of anti-oxidant vitamins with cardiovascular events. We investigated the prospective relationship between dietary intake of anti-oxidant vitamins and incident adverse cardiovascular outcomes amongst Hong Kong Chinese. Methods: In this prospective population-based study, baseline dietary intake of anti-oxidant vitamins (A, C, and E) were assessed using a food frequency questionnaire in 875 Chinese participants from the Hong Kong Cardiovascular Risk Factor Prevalence Study (CRISPS) in 1995–1996. The adjusted hazard ratio (HR) of incident adverse cardiovascular outcomes, defined as the first recorded diagnosis of cardiovascular deaths, non-fatal myocardial infarction or non-fatal stroke, and coronary or other arterial revascularizations, was calculated per unit intake of each vitamin using multivariable Cox regression. Results: Over a median follow-up of 22 years, 85 participants (9.7%) developed adverse cardiovascular outcomes. Dietary intakes of vitamin A, C, and E were independently and inversely associated with incident adverse cardiovascular outcomes (HR 0.68, 95%CI 0.53–0.88, p = 0.003 for vitamin A; HR 0.66, 95%CI 0.52–0.85, p = 0.001 for vitamin C; and HR 0.57, 95%CI 0.38–0.86, p = 0.017 for vitamin E) after adjustments for conventional cardiovascular risk factors at baseline. Conclusions: Dietary intakes of anti-oxidant vitamins A, C, and E reduced the risk of adverse cardiovascular outcomes in Hong Kong Chinese.
Collapse
Affiliation(s)
- Chi-Ho Lee
- Department of Medicine, University of Hong Kong, Hong Kong, China.
- Research Center of Heart, Brain, Hormone and Healthy Aging, University of Hong Kong, Hong Kong, China.
| | - Ruth S M Chan
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China.
| | - Helen Y L Wan
- Department of Medicine, University of Hong Kong, Hong Kong, China.
| | - Yu-Cho Woo
- Department of Medicine, University of Hong Kong, Hong Kong, China.
| | - Chloe Y Y Cheung
- Department of Medicine, University of Hong Kong, Hong Kong, China.
| | - Carol H Y Fong
- Department of Medicine, University of Hong Kong, Hong Kong, China.
| | - Bernard M Y Cheung
- Department of Medicine, University of Hong Kong, Hong Kong, China.
- Research Center of Heart, Brain, Hormone and Healthy Aging, University of Hong Kong, Hong Kong, China.
| | - Tai-Hing Lam
- The School of Public Health, University of Hong Kong, Hong Kong, China.
| | - Edward Janus
- Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, Melbourne, Victoria 3021, Australia.
- General Medical Unit, Western Health, St Albans, Victoria 3021, Australia.
| | - Jean Woo
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China.
| | - Karen S L Lam
- Department of Medicine, University of Hong Kong, Hong Kong, China.
- Research Center of Heart, Brain, Hormone and Healthy Aging, University of Hong Kong, Hong Kong, China.
| |
Collapse
|
9
|
|
10
|
Guo C, Ma R, Liu X, Chen T, Li Y, Yu Y, Duan J, Zhou X, Li Y, Sun Z. Silica nanoparticles promote oxLDL-induced macrophage lipid accumulation and apoptosis via endoplasmic reticulum stress signaling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 631-632:570-579. [PMID: 29533793 DOI: 10.1016/j.scitotenv.2018.02.312] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 02/26/2018] [Accepted: 02/26/2018] [Indexed: 05/15/2023]
Abstract
Oxidized low-density lipoprotein (oxLDL), a marker of hyperlipidemia, plays a pivotal role in the development of atherosclerosis through the induction of macrophage-derived foam cell formation and thereafter apoptosis. Previous studies have indicated that silica nanoparticle (SiNPs) may exert a proatherogenic role, which could induce endothelial dysfunction, and monocytes infiltration. However, little is known about SiNPs' effects on macrophage-derived foam cell formation and apoptosis in the pathogenesis of atherosclerosis. In this study, we investigated the effects of SiNPs and oxLDL coexposure on macrophage-derived lipid metabolism, foam cell and apoptosis by using Raw264.7 cells. As a result, SiNPs enhanced cytotoxicity, apoptosis, and lipid accumulation upon oxLDL stimulation. Furthermore, quantitative determination of the expression levels of genes involved in cholesterol influx or efflux showed significantly up-regulated expressions of CD36 and SRA, whereas down-regulated expressions of ATP-binding cassette A1 (ABCA1), ABCG1, and SRB1 in oxLDL-treated macrophages, especially upon the co-exposure with SiNPs. It indicated that SiNPs promoted lipid accumulation in macrophage cells through not only facilitating cholesterol influx but also inhibiting cholesterol efflux. Endoplasmic reticulum (ER) is specialized for the production, modification, even trafficking of lipids. Interestingly, ER response was triggered upon oxLDL treatment, while SiNPs coexposure augmented the ER stress. Taken together, our results revealed that SiNPs promoted oxLDL-induced macrophage foam cell formation and apoptosis, which may be mediated by ER stress signaling. Thus we propose future researches needed for a better understanding of NPs' toxicity and their interactions with various pathophysiological conditions.
Collapse
Affiliation(s)
- Caixia Guo
- Department of Occupational Health and Environmental Health, School of Public Health, Capital Medical University, Beijing 100069, China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China
| | - Ru Ma
- Department of Occupational Health and Environmental Health, School of Public Health, Capital Medical University, Beijing 100069, China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China
| | - Xiaoying Liu
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, China
| | - Tian Chen
- Department of Occupational Health and Environmental Health, School of Public Health, Capital Medical University, Beijing 100069, China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China
| | - Yang Li
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, China
| | - Yang Yu
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, China
| | - Junchao Duan
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, China
| | - Xianqing Zhou
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, China
| | - Yanbo Li
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, China.
| | - Zhiwei Sun
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, China.
| |
Collapse
|
11
|
de Grooth HJ, Manubulu-Choo WP, Zandvliet AS, Spoelstra-de Man AME, Girbes AR, Swart EL, Oudemans-van Straaten HM. Vitamin C Pharmacokinetics in Critically Ill Patients: A Randomized Trial of Four IV Regimens. Chest 2018. [PMID: 29522710 DOI: 10.1016/j.chest.2018.02.025] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Early high-dose IV vitamin C is being investigated as adjuvant therapy in patients who are critically ill, but the optimal dose and infusion method are unclear. The primary aim of this study was to describe the dose-plasma concentration relationship and safety of four different dosing regimens. METHODS This was a four-group randomized pharmacokinetic trial. Patients who were critically ill with multiple organ dysfunction were randomized to receive 2 or 10 g/d vitamin C as a twice daily bolus infusion or continuous infusion for 48 h. End points were plasma vitamin C concentrations during 96 h, 12-h urine excretion of vitamin C, and oxalate excretion and base excess. A population pharmacokinetic model was developed using NONMEM. RESULTS Twenty patients were included. A two-compartment pharmacokinetic model with creatinine clearance and weight as independent covariates described all four regimens best. With 2 g/d bolus, plasma vitamin C concentrations at 1 h were 29 to 50 mg/L and trough concentrations were 5.6 to 16 mg/L. With 2 g/d continuous, steady-state concentrations were 7 to 37 mg/L at 48 h. With 10 g/d bolus, 1-h concentrations were 186 to 244 mg/L and trough concentrations were 14 to 55 mg/L. With 10 g/d continuous, steady-state concentrations were 40 to 295 mg/L at 48 h. Oxalate excretion and base excess were increased in the 10 g/d dose. Forty-eight hours after discontinuation, plasma concentrations declined to hypovitaminosis levels in 15% of patients. CONCLUSIONS The 2 g/d dose was associated with normal plasma concentrations, and the 10 g/d dose was associated with supranormal plasma concentrations, increased oxalate excretion, and metabolic alkalosis. Sustained therapy is needed to prevent hypovitaminosis. TRIAL REGISTRY ClinicalTrials.gov; No.: NCT02455180; URL: www.clinicaltrials.gov.
Collapse
Affiliation(s)
- Harm-Jan de Grooth
- Department of Intensive Care, VU University Medical Center, Amsterdam, The Netherlands; Department of Anesthesiology, VU University Medical Center, Amsterdam, The Netherlands.
| | - Wai-Ping Manubulu-Choo
- Department of Clinical Pharmacology and Pharmacy, VU University Medical Center, Amsterdam, The Netherlands; Department of Pharmacy, Westfriesgasthuis, Hoorn, The Netherlands
| | - Anthe S Zandvliet
- Department of Clinical Pharmacology and Pharmacy, VU University Medical Center, Amsterdam, The Netherlands
| | | | - Armand R Girbes
- Department of Intensive Care, VU University Medical Center, Amsterdam, The Netherlands
| | - Eleonora L Swart
- Department of Clinical Pharmacology and Pharmacy, VU University Medical Center, Amsterdam, The Netherlands
| | | |
Collapse
|
12
|
Vitamin C, Aging and Alzheimer's Disease. Nutrients 2017; 9:nu9070670. [PMID: 28654021 PMCID: PMC5537785 DOI: 10.3390/nu9070670] [Citation(s) in RCA: 123] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 06/01/2017] [Accepted: 06/13/2017] [Indexed: 02/07/2023] Open
Abstract
Accumulating evidence in mice models of accelerated senescence indicates a rescuing role of ascorbic acid in premature aging. Supplementation of ascorbic acid appeared to halt cell growth, oxidative stress, telomere attrition, disorganization of chromatin, and excessive secretion of inflammatory factors, and extend lifespan. Interestingly, ascorbic acid (AA) was also found to positively modulate inflamm-aging and immunosenescence, two hallmarks of biological aging. Moreover, ascorbic acid has been shown to epigenetically regulate genome integrity and stability, indicating a key role of targeted nutrition in healthy aging. Growing in vivo evidence supports the role of ascorbic acid in ameliorating factors linked to Alzheimer’s disease (AD) pathogenesis, although evidence in humans yielded equivocal results. The neuroprotective role of ascorbic acid not only relies on the general free radical trapping, but also on the suppression of pro-inflammatory genes, mitigating neuroinflammation, on the chelation of iron, copper, and zinc, and on the suppression of amyloid-beta peptide (Aβ) fibrillogenesis. Epidemiological evidence linking diet, one of the most important modifiable lifestyle factors, and risk of Alzheimer's disease is rapidly increasing. Thus, dietary interventions, as a way to epigenetically modulate the human genome, may play a role in the prevention of AD. The present review is aimed at providing an up to date overview of the main biological mechanisms that are associated with ascorbic acid supplementation/bioavailability in the process of aging and Alzheimer’s disease. In addition, we will address new fields of research and future directions.
Collapse
|
13
|
Parker WH, Rhea EM, Qu ZC, Hecker MR, May JM. Intracellular ascorbate tightens the endothelial permeability barrier through Epac1 and the tubulin cytoskeleton. Am J Physiol Cell Physiol 2016; 311:C652-C662. [PMID: 27605450 DOI: 10.1152/ajpcell.00076.2016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 08/21/2016] [Indexed: 12/28/2022]
Abstract
Vitamin C, or ascorbic acid, both tightens the endothelial permeability barrier in basal cells and also prevents barrier leak induced by inflammatory agents. Barrier tightening by ascorbate in basal endothelial cells requires nitric oxide derived from activation of nitric oxide synthase. Although ascorbate did not affect cyclic AMP levels in our previous study, there remains a question of whether it might activate downstream cyclic AMP-dependent pathways. In this work, we found in both primary and immortalized cultured endothelial cells that ascorbate tightened the endothelial permeability barrier by ∼30%. In human umbilical vein endothelial cells, this occurred at what are likely physiologic intracellular ascorbate concentrations. In so doing, ascorbate decreased measures of oxidative stress and also flattened the cells to increase cell-to-cell contact. Inhibition of downstream cyclic AMP-dependent proteins via protein kinase A did not prevent ascorbate from tightening the endothelial permeability barrier, whereas inhibition of Epac1 did block the ascorbate effect. Although Epac1 was required, its mediator Rap1 was not activated. Furthermore, ascorbate acutely stabilized microtubules during depolymerization induced by colchicine and nocodazole. Over several days in culture, ascorbate also increased the amount of stable acetylated α-tubulin. Microtubule stabilization was further suggested by the finding that ascorbate increased the amount of Epac1 bound to α-tubulin. These results suggest that physiologic ascorbate concentrations tighten the endothelial permeability barrier in unstimulated cells by stabilizing microtubules in a manner downstream of cyclic AMP that might be due both to increasing nitric oxide availability and to scavenging of reactive oxygen or nitrogen species.
Collapse
Affiliation(s)
- William H Parker
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee; and
| | - Elizabeth Meredith Rhea
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Zhi-Chao Qu
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee; and
| | - Morgan R Hecker
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee; and
| | - James M May
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee; and
| |
Collapse
|
14
|
May JM. Ascorbic acid repletion: A possible therapy for diabetic macular edema? Free Radic Biol Med 2016; 94:47-54. [PMID: 26898503 PMCID: PMC4844774 DOI: 10.1016/j.freeradbiomed.2016.02.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 02/10/2016] [Accepted: 02/16/2016] [Indexed: 02/07/2023]
Abstract
Macular edema poses a significant risk for visual loss in persons with diabetic retinopathy. It occurs when plasma constituents and fluid leak out of damaged retinal microvasculature in the area of the macula, causing loss of central vision. Apoptotic loss of pericytes surrounding capillaries is perhaps the earliest feature of diabetic vascular damage in the macula, which is also associated with dysfunction of the endothelium and loss of the otherwise very tight endothelial permeability barrier. Increased oxidative stress is a key feature of damage to both cell types, mediated by excess superoxide from glucose-induced increases in mitochondrial metabolism, as well as by activation of the receptor for advanced glycation end products (RAGE). The latter in turn activates multiple pathways, some of which lead to increased oxidative stress, such as those involving NF-ĸB, NADPH oxidase, and endothelial nitric oxide synthase. Such cellular oxidative stress is associated with low cellular and plasma ascorbic acid levels in many subjects with diabetes in poor glycemic control. Whether repletion of low ascorbate in retinal endothelium and pericytes might help to prevent diabetic macular edema is unknown. However, cell culture studies show that the vitamin prevents high-glucose and RAGE-induced apoptosis in both cell types, that it preserves nitric oxide generated by endothelial cells, and that it tightens the leaky endothelial permeability barrier. Although these findings need to be confirmed in pre-clinical animal studies, it is worth considering clinical trials to determine whether adequate ascorbate repletion is possible and whether it might help to delay or even reverse early diabetic macular edema.
Collapse
Affiliation(s)
- James M May
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232-6303, United States.
| |
Collapse
|
15
|
Ulker E, Parker WH, Raj A, Qu ZC, May JM. Ascorbic acid prevents VEGF-induced increases in endothelial barrier permeability. Mol Cell Biochem 2015; 412:73-9. [PMID: 26590088 DOI: 10.1007/s11010-015-2609-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 11/14/2015] [Indexed: 02/07/2023]
Abstract
Vascular endothelial growth factor (VEGF) increases endothelial barrier permeability, an effect that may contribute to macular edema in diabetic retinopathy. Since vitamin C, or ascorbic acid, can tighten the endothelial permeability barrier, we examined whether it could prevent the increase in permeability due to VEGF in human umbilical vein endothelial cells (HUVECs). As previously observed, VEGF increased HUVEC permeability to radiolabeled inulin within 60 min in a concentration-dependent manner. Loading the cells with increasing concentrations of ascorbate progressively prevented the leakage caused by 100 ng/ml VEGF, with a significant inhibition at 13 µM and complete inhibition at 50 µM. Loading cells with 100 µM ascorbate also decreased the basal generation of reactive oxygen species and prevented the increase caused by both 100 ng/ml VEGF. VEGF treatment decreased intracellular ascorbate by 25%, thus linking ascorbate oxidation to its prevention of VEGF-induced barrier leakage. The latter was blocked by treating the cells with 60 µM L-NAME (but not D-NAME) as well as by 30 µM sepiapterin, a precursor of tetrahydrobiopterin that is required for proper function of endothelial nitric oxide synthase (eNOS). These findings suggest that VEGF-induced barrier leakage uncouples eNOS. Ascorbate inhibition of the VEGF effect could thus be due either to scavenging superoxide or to peroxynitrite generated by the uncoupled eNOS, or more likely to its ability to recycle tetrahydrobiopterin, thus avoiding enzyme uncoupling in the first place. Ascorbate prevention of VEGF-induced increases in endothelial permeability opens the possibility that its repletion could benefit diabetic macular edema.
Collapse
Affiliation(s)
- Esad Ulker
- Department of Medicine, Vanderbilt University School of Medicine, 7465 Medical Research Building IV, Nashville, TN, 37232-0475, USA
| | - William H Parker
- Department of Medicine, Vanderbilt University School of Medicine, 7465 Medical Research Building IV, Nashville, TN, 37232-0475, USA
| | - Amita Raj
- Department of Medicine, Vanderbilt University School of Medicine, 7465 Medical Research Building IV, Nashville, TN, 37232-0475, USA
| | - Zhi-chao Qu
- Department of Medicine, Vanderbilt University School of Medicine, 7465 Medical Research Building IV, Nashville, TN, 37232-0475, USA
| | - James M May
- Department of Medicine, Vanderbilt University School of Medicine, 7465 Medical Research Building IV, Nashville, TN, 37232-0475, USA.
| |
Collapse
|
16
|
Curhan SG, Stankovic KM, Eavey RD, Wang M, Stampfer MJ, Curhan GC. Carotenoids, vitamin A, vitamin C, vitamin E, and folate and risk of self-reported hearing loss in women. Am J Clin Nutr 2015; 102:1167-75. [PMID: 26354537 PMCID: PMC4625586 DOI: 10.3945/ajcn.115.109314] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 08/04/2015] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Higher intake of certain vitamins may protect against cochlear damage from vascular compromise and oxidative stress, thereby reducing risk of acquired hearing loss, but data are limited. OBJECTIVE We prospectively examined the relation between carotenoids, vitamin A, vitamin C, vitamin E, and folate intake and risk of self-reported hearing loss in women. DESIGN This prospective cohort study followed 65,521 women in the Nurses' Health Study II from 1991 to 2009. Baseline and updated information obtained from validated biennial questionnaires was used in Cox proportional hazards regression models to examine independent associations between nutrient intake and self-reported hearing loss. RESULTS After 1,084,598 person-years of follow-up, 12,789 cases of incident hearing loss were reported. After multivariable adjustment, we observed modest but statistically significant inverse associations between higher intake of β-carotene and β-cryptoxanthin and risk of hearing loss. In comparison with women in the lowest quintile of intake, the multivariable-adjusted RR of hearing loss among women in the highest quintile was 0.88 (95% CI: 0.81, 0.94; P-trend < 0.001) for β-carotene and 0.90 (95% CI: 0.84, 0.96; P-trend < 0.001) for β-cryptoxanthin. In comparison with women with folate intake 200-399 μg/d, very low folate intake (<200 μg/d) was associated with higher risk (RR: 1.19; 95% CI: 1.01, 1.41), and higher intake tended to be associated with lower risk (P-trend = 0.04). No significant associations were observed for intakes of other carotenoids or vitamin A. Higher vitamin C intake was associated with higher risk; in comparison with women with intake <75 mg/d, the RR among women with vitamin C intake ≥1000 mg/d (mainly supplemental) was 1.22 (95% CI: 1.06, 1.42; P-trend = 0.02). There was no significant trend between intake of vitamin E intake and risk. CONCLUSION Higher intakes of β-carotene, β-cryptoxanthin, and folate, whether total or from diet, are associated with lower risk of hearing loss, whereas higher vitamin C intake is associated with higher risk.
Collapse
Affiliation(s)
- Sharon G Curhan
- Channing Division of Network Medicine and Harvard Medical School, Boston MA
| | - Konstantina M Stankovic
- Eaton-Peabody Laboratories and Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA; Department of Otology and Laryngology, Harvard Medical School, Boston, MA; Program in Speech and Hearing Bioscience and Technology, Division of Health Science and Technology, Harvard and Massachusetts Institute of Technology, Boston, MA
| | - Roland D Eavey
- Vanderbilt Bill Wilkerson Center for Otolaryngology and Communication Sciences, Vanderbilt University School of Medicine, Nashville, TN; and
| | - Molin Wang
- Channing Division of Network Medicine and Departments of Biostatistics and Epidemiology, Harvard School of Public Health, Boston, MA
| | - Meir J Stampfer
- Channing Division of Network Medicine and Epidemiology, Harvard School of Public Health, Boston, MA
| | - Gary C Curhan
- Channing Division of Network Medicine and Renal Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA; Epidemiology, Harvard School of Public Health, Boston, MA, Harvard Medical School, Boston MA
| |
Collapse
|
17
|
Brown JA, Pensabene V, Markov DA, Allwardt V, Neely MD, Shi M, Britt CM, Hoilett OS, Yang Q, Brewer BM, Samson PC, McCawley LJ, May JM, Webb DJ, Li D, Bowman AB, Reiserer RS, Wikswo JP. Recreating blood-brain barrier physiology and structure on chip: A novel neurovascular microfluidic bioreactor. BIOMICROFLUIDICS 2015; 9:054124. [PMID: 26576206 PMCID: PMC4627929 DOI: 10.1063/1.4934713] [Citation(s) in RCA: 275] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 10/10/2015] [Indexed: 05/04/2023]
Abstract
The blood-brain barrier (BBB) is a critical structure that serves as the gatekeeper between the central nervous system and the rest of the body. It is the responsibility of the BBB to facilitate the entry of required nutrients into the brain and to exclude potentially harmful compounds; however, this complex structure has remained difficult to model faithfully in vitro. Accurate in vitro models are necessary for understanding how the BBB forms and functions, as well as for evaluating drug and toxin penetration across the barrier. Many previous models have failed to support all the cell types involved in the BBB formation and/or lacked the flow-created shear forces needed for mature tight junction formation. To address these issues and to help establish a more faithful in vitro model of the BBB, we have designed and fabricated a microfluidic device that is comprised of both a vascular chamber and a brain chamber separated by a porous membrane. This design allows for cell-to-cell communication between endothelial cells, astrocytes, and pericytes and independent perfusion of both compartments separated by the membrane. This NeuroVascular Unit (NVU) represents approximately one-millionth of the human brain, and hence, has sufficient cell mass to support a breadth of analytical measurements. The NVU has been validated with both fluorescein isothiocyanate (FITC)-dextran diffusion and transendothelial electrical resistance. The NVU has enabled in vitro modeling of the BBB using all human cell types and sampling effluent from both sides of the barrier.
Collapse
Affiliation(s)
| | - Virginia Pensabene
- Department of Biomedical Engineering, Vanderbilt University , Nashville, Tennessee 37235, USA
| | | | - Vanessa Allwardt
- Department of Physics and Astronomy, Vanderbilt University , Nashville, Tennessee 37235, USA
| | - M Diana Neely
- Department of Neurology, Vanderbilt Kennedy Center, Vanderbilt Brain Institute, Vanderbilt Center in Molecular Toxicology, Vanderbilt University , Nashville, Tennessee 37232, USA
| | - Mingjian Shi
- Department of Biological Sciences, Vanderbilt University , Nashville, Tennessee 37235, USA
| | - Clayton M Britt
- Department of Physics and Astronomy, Vanderbilt University , Nashville, Tennessee 37235, USA
| | - Orlando S Hoilett
- Department of Physics and Astronomy, Vanderbilt University , Nashville, Tennessee 37235, USA
| | - Qing Yang
- Department of Physics and Astronomy, Vanderbilt University , Nashville, Tennessee 37235, USA
| | - Bryson M Brewer
- Department of Mechanical Engineering, Vanderbilt University , Nashville, Tennessee 37235, USA
| | | | | | - James M May
- Department of Molecular Physiology and Biophysics, Vanderbilt University , Nashville, Tennessee 37235, USA
| | - Donna J Webb
- Department of Biological Sciences, Vanderbilt University , Nashville, Tennessee 37235, USA
| | - Deyu Li
- Department of Mechanical Engineering, Vanderbilt University , Nashville, Tennessee 37235, USA
| | - Aaron B Bowman
- Department of Neurology, Vanderbilt Kennedy Center, Vanderbilt Brain Institute, Vanderbilt Center in Molecular Toxicology, Vanderbilt University , Nashville, Tennessee 37232, USA
| | | | | |
Collapse
|
18
|
Parker WH, Qu ZC, May JM. Intracellular Ascorbate Prevents Endothelial Barrier Permeabilization by Thrombin. J Biol Chem 2015; 290:21486-97. [PMID: 26152729 DOI: 10.1074/jbc.m115.662098] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Indexed: 12/11/2022] Open
Abstract
Intracellular ascorbate (vitamin C) has previously been shown to tighten the endothelial barrier and maintain barrier integrity during acute inflammation in vitro. However, the downstream effectors of ascorbate in the regulation of endothelial permeability remain unclear. In this study, we evaluated ascorbate as a mediator of thrombin-induced barrier permeabilization in human umbilical vein endothelial cells and their immortalized hybridoma line, EA.hy926. We found that the vitamin fully prevented increased permeability to the polysaccharide inulin by thrombin in a dose-dependent manner, and it took effect both before and after subjection to thrombin. Thrombin exposure consumed intracellular ascorbate but not the endogenous antioxidant GSH. Likewise, the antioxidants dithiothreitol and tempol did not reverse permeabilization. We identified a novel role for ascorbate in preserving cAMP during thrombin stimulation, resulting in two downstream effects. First, ascorbate maintained the cortical actin cytoskeleton in a Rap1- and Rac1-dependent manner, thus preserving stable adherens junctions between adjacent cells. Second, ascorbate prevented actin polymerization and formation of stress fibers by reducing the activation of RhoA and phosphorylation of myosin light chain. Although ascorbate and thrombin both required calcium for their respective effects, ascorbate did not prevent thrombin permeabilization by obstructing calcium influx. However, preservation of cAMP by ascorbate was found to depend on both the production of nitric oxide by endothelial nitric-oxide synthase, which ascorbate is known to activate, and the subsequent generation cGMP by guanylate cyclase. Together, these data implicate ascorbate in the prevention of inflammatory endothelial barrier permeabilization and explain the underlying signaling mechanism.
Collapse
Affiliation(s)
- William H Parker
- From the Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-6303
| | - Zhi-chao Qu
- From the Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-6303
| | - James M May
- From the Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-6303
| |
Collapse
|
19
|
Desai CK, Huang J, Lokhandwala A, Fernandez A, Riaz IB, Alpert JS. The role of vitamin supplementation in the prevention of cardiovascular disease events. Clin Cardiol 2014; 37:576-81. [PMID: 24863141 PMCID: PMC6649521 DOI: 10.1002/clc.22299] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 04/25/2014] [Accepted: 04/29/2014] [Indexed: 12/17/2022] Open
Abstract
The production, sale, and consumption of multiple vitamins is a multibillion-dollar industry. Most Americans take some form of supplement ostensibly for prevention of cardiovascular disease. It has been claimed that vitamin A retards atherogenesis. Vitamin C is an antioxidant and is thought to possibly decrease free radical-induced endothelial injury, which can lead to atherosclerotic plaque formation. Vitamin E has been extensively studied for its possible effects on platelet function as well as inhibition of foam-cell formation. Low levels of vitamin D have been thought to negatively impact myocardial structure and increase the risk for cardiovascular events. Increased intake of vitamin B6, B12, and folate has been associated with reduction of homocysteine levels; elevated homocysteine blood levels have been associated with the occurrence of stroke, heart attack, and cardiovascular death. The purpose of this study was to review the currently available literature for vitamin supplementation with respect to prevention of cardiovascular disease. Unfortunately, the current evidence suggests no benefit exists with vitamin supplementation in the general US population. Further research is needed to evaluate whether there are specific populations that might benefit from vitamin supplementation.
Collapse
Affiliation(s)
- Chirag K. Desai
- Department of MedicineUniversity of Arizona College of MedicineTucsonArizona
| | - Jennifer Huang
- Department of MedicineUniversity of Arizona College of MedicineTucsonArizona
| | - Adil Lokhandwala
- Department of MedicineUniversity of Arizona College of MedicineTucsonArizona
| | - Aaron Fernandez
- Department of MedicineUniversity of Arizona College of MedicineTucsonArizona
| | - Irbaz Bin Riaz
- Department of MedicineUniversity of Arizona College of MedicineTucsonArizona
| | - Joseph S. Alpert
- Department of MedicineUniversity of Arizona College of MedicineTucsonArizona
| |
Collapse
|
20
|
Wagner SC, Markosian B, Ajili N, Dolan BR, Kim AJ, Alexandrescu DT, Dasanu CA, Minev B, Koropatnick J, Marincola FM, Riordan NH. Intravenous ascorbic acid as an adjuvant to interleukin-2 immunotherapy. J Transl Med 2014; 12:127. [PMID: 24884532 PMCID: PMC4028098 DOI: 10.1186/1479-5876-12-127] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 04/29/2014] [Indexed: 02/06/2023] Open
Abstract
Interleukin-2 (IL-2) therapy has been demonstrated to induce responses in 10-20% of advanced melanoma and renal cell carcinoma patients, which translates into durable remissions in up to half of the responsers. Unfortunately the use of IL-2 has been associated with severe toxicity and death. It has been previously observed and reported that IL-2 therapy causes a major drop in circulating levels of ascorbic acid (AA). The IL-2 induced toxicity shares many features with sepsis such as capillary leakage, systemic complement activation, and a relatively non-specific rise in inflammatory mediators such as TNF-alpha, C-reactive protein, and in advanced cases organ failure. Animal models and clinical studies have shown rapid depletion of AA in conditions of sepsis and amelioration associated with administration of AA (JTM 9:1-7, 2011). In contrast to other approaches to dealing with IL-2 toxicity, which may also interfere with therapeutic effects, AA possesses the added advantage of having direct antitumor activity through cytotoxic mechanisms and suppression of angiogenesis. Here we present a scientific rationale to support the assessment of intravenous AA as an adjuvant to decrease IL-2 mediated toxicity and possibly increase treatment efficacy.
Collapse
Affiliation(s)
| | | | | | | | - Andy J Kim
- Batu Biologics, San Diego, California, USA
| | - Doru T Alexandrescu
- Moores UCSD Cancer Center, University of California San Diego, San Diego, USA
| | - Constantin A Dasanu
- Department of Hematology and Oncology, University of Connecticut, Hartford, Connecticut, USA
| | - Boris Minev
- Moores UCSD Cancer Center, University of California San Diego, San Diego, USA
- Genelux Corporation, San Diego Science Center, San Diego, California, USA
- Division of Neurosurgery, University of California San Diego, San Diego, USA
| | - James Koropatnick
- Lawson Health Research Institute and Department of Oncology, The University of Western Ontario, London, Ontario, Canada
| | | | | |
Collapse
|
21
|
Kennard JA, Harrison FE. Intravenous ascorbate improves spatial memory in middle-aged APP/PSEN1 and wild type mice. Behav Brain Res 2014; 264:34-42. [PMID: 24508240 PMCID: PMC3980584 DOI: 10.1016/j.bbr.2014.01.044] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 01/23/2014] [Accepted: 01/28/2014] [Indexed: 02/08/2023]
Abstract
The present study investigated the effects of a single intravenous (i.v.) dose of Vitamin C (ascorbate, ASC) on spatial memory in APP/PSEN1 mice, an Alzheimer's disease model. First, we confirmed the uptake time course in ASC-depleted gulo (-/-) mice, which cannot synthesize ASC. Differential tissue uptake was seen based on ASC transporter distribution. Liver (SVCT1 and SVCT2) ASC was elevated at 30, 60 and 120 min post-treatment (125 mg/kg, i.v.), whereas spleen (SVCT2) ASC increased at 60 and 120 min. There was no detectable change in cortical (SVCT2 at choroid plexus, and neurons) ASC within the 2-h interval, although the cortex preferentially retained ASC. APP/PSEN1 and wild type (WT) mice at three ages (3, 9, or 20 months) were treated with ASC (125 mg/kg, i.v.) or saline 45 min before testing on the Modified Y-maze, a two-trial task of spatial memory. Memory declined with age and ASC treatment improved performance in 9-month-old APP/PSEN1 and WT mice. APP/PSEN1 mice displayed no behavioral impairment relative to WT controls. Although dopamine and metabolite DOPAC decreased in the nucleus accumbens with age, and improved spatial memory was correlated with increased dopamine in saline treated mice, acute ASC treatment did not alter monoamine levels in the nucleus accumbens. These data show that the Modified Y-maze is sensitive to age-related deficits, but not additional memory deficits due to amyloid pathology in APP/PSEN1 mice. They also suggest improvements in short-term spatial memory were not due to changes in the neuropathological features of AD or monoamine signaling.
Collapse
Affiliation(s)
- John A Kennard
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, United States.
| | - Fiona E Harrison
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, United States
| |
Collapse
|
22
|
Ascorbic acid and the brain: rationale for the use against cognitive decline. Nutrients 2014; 6:1752-81. [PMID: 24763117 PMCID: PMC4011065 DOI: 10.3390/nu6041752] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 03/24/2014] [Accepted: 04/10/2014] [Indexed: 12/21/2022] Open
Abstract
This review is focused upon the role of ascorbic acid (AA, vitamin C) in the promotion of healthy brain aging. Particular attention is attributed to the biochemistry and neuronal metabolism interface, transport across tissues, animal models that are useful for this area of research, and the human studies that implicate AA in the continuum between normal cognitive aging and age-related cognitive decline up to Alzheimer’s disease. Vascular risk factors and comorbidity relationships with cognitive decline and AA are discussed to facilitate strategies for advancing AA research in the area of brain health and neurodegeneration.
Collapse
|
23
|
May JM, Harrison FE. Role of vitamin C in the function of the vascular endothelium. Antioxid Redox Signal 2013; 19:2068-83. [PMID: 23581713 PMCID: PMC3869438 DOI: 10.1089/ars.2013.5205] [Citation(s) in RCA: 202] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 03/26/2013] [Accepted: 04/14/2013] [Indexed: 12/28/2022]
Abstract
SIGNIFICANCE Vitamin C, or ascorbic acid, has long been known to participate in several important functions in the vascular bed in support of endothelial cells. These functions include increasing the synthesis and deposition of type IV collagen in the basement membrane, stimulating endothelial proliferation, inhibiting apoptosis, scavenging radical species, and sparing endothelial cell-derived nitric oxide to help modulate blood flow. Although ascorbate may not be able to reverse inflammatory vascular diseases such as atherosclerosis, it may well play a role in preventing the endothelial dysfunction that is the earliest sign of many such diseases. RECENT ADVANCES Beyond simply preventing scurvy, evidence is mounting that ascorbate is required for optimal function of many dioxygenase enzymes in addition to those involved in collagen synthesis. Several of these enzymes regulate the transcription of proteins involved in endothelial function, proliferation, and survival, including hypoxia-inducible factor-1α and histone and DNA demethylases. More recently, ascorbate has been found to acutely tighten the endothelial permeability barrier and, thus, may modulate access of ascorbate and other molecules into tissues and organs. CRITICAL ISSUES The issue of the optimal cellular content of ascorbate remains unresolved, but it appears that low millimolar ascorbate concentrations are normal in most animal tissues, in human leukocytes, and probably in the endothelium. Although there may be little benefit of increasing near maximal cellular ascorbate concentrations in normal people, many diseases and conditions have either systemic or localized cellular ascorbate deficiency as a cause for endothelial dysfunction, including early atherosclerosis, sepsis, smoking, and diabetes. FUTURE DIRECTIONS A key focus for future studies of ascorbate and the vascular endothelium will likely be to determine the mechanisms and clinical relevance of ascorbate effects on endothelial function, permeability, and survival in diseases that cause endothelial dysfunction.
Collapse
Affiliation(s)
- James M May
- Department of Medicine, Vanderbilt University School of Medicine , Nashville, Tennessee
| | | |
Collapse
|
24
|
Heo JH, Hyon-Lee, Lee KM. The possible role of antioxidant vitamin C in Alzheimer's disease treatment and prevention. Am J Alzheimers Dis Other Demen 2013; 28:120-5. [PMID: 23307795 PMCID: PMC10852723 DOI: 10.1177/1533317512473193] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Oxidative stress is suggested to play a major role in the pathogenesis of Alzheimer's disease (AD). Among the antioxidants, vitamin C has been regarded as the most important one in neural tissue. It also decreases β-amyloid generation and acetylcholinesterase activity and prevents endothelial dysfunction by regulating nitric oxide, a newly discovered factor in the pathogenesis and progression of AD. However, clinical trials using antioxidants, including vitamin C, in patients with AD yielded equivocal results. The current article discusses the relevance of vitamin C in the cellular and molecular pathogenesis of AD and explores its therapeutic potential against this neurodegenerative disorder.
Collapse
Affiliation(s)
- Jae-Hyeok Heo
- Department of Neurology, Seoul Medical Center, Seoul, Korea
| | - Hyon-Lee
- Department of Neurology, Seoul National University Hospital, Seoul, Korea
| | - Kyoung-Min Lee
- Department of Neurology, Seoul National University Hospital, Seoul, Korea
| |
Collapse
|
25
|
Mori M, Hamada A, Mori H, Yamori Y, Tsuda K. Effects of cooking using multi-ply cookware on absorption of potassium and vitamins: a randomized double-blind placebo control study. Int J Food Sci Nutr 2012; 63:530-6. [PMID: 22229802 PMCID: PMC3411121 DOI: 10.3109/09637486.2011.642342] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This 2-week interventional study involved a randomized allocation of subjects into three groups: Group A (daily ingestion of 350 g vegetables cooked without water using multi-ply [multilayer-structured] cookware), Group B (daily ingestion of 350g vegetables; ordinary cookware) and Group C (routine living). Before and after intervention, each subject underwent health examination with 24-h urine sampling. Blood vitamin C significantly increased after intervention from the baseline in Group A (P < 0.01) and Group B (P < 0.05). β-Carotene levels also increased significantly after intervention in Group A (P < 0.01) and Group B (P < 0.01). Oxidized low-density lipoprotein decreased significantly after intervention in Group A (P < 0.01). In Group A, 24-h urinary potassium excretion increased significantly (P < 0.01) and 24-h urinary sodium (Na)/K ratio improved significantly (P < 0.05) after intervention. In conclusion, a cooking method modification with multi-ply cookware improved absorption of nutrients from vegetables and enhanced effective utilization of the antioxidant potentials of vegetable nutrients.
Collapse
Affiliation(s)
- Mari Mori
- Mukogawa Women's University Institute for World Health Development, Edagawa-cho, Nishinomiya-shi, Hyogo, Japan.
| | | | | | | | | |
Collapse
|
26
|
Ichim TE, Minev B, Braciak T, Luna B, Hunninghake R, Mikirova NA, Jackson JA, Gonzalez MJ, Miranda-Massari JR, Alexandrescu DT, Dasanu CA, Bogin V, Ancans J, Stevens RB, Markosian B, Koropatnick J, Chen CS, Riordan NH. Intravenous ascorbic acid to prevent and treat cancer-associated sepsis? J Transl Med 2011; 9:25. [PMID: 21375761 PMCID: PMC3061919 DOI: 10.1186/1479-5876-9-25] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Accepted: 03/04/2011] [Indexed: 02/07/2023] Open
Abstract
The history of ascorbic acid (AA) and cancer has been marked with controversy. Clinical studies evaluating AA in cancer outcome continue to the present day. However, the wealth of data suggesting that AA may be highly beneficial in addressing cancer-associated inflammation, particularly progression to systemic inflammatory response syndrome (SIRS) and multi organ failure (MOF), has been largely overlooked. Patients with advanced cancer are generally deficient in AA. Once these patients develop septic symptoms, a further decrease in ascorbic acid levels occurs. Given the known role of ascorbate in: a) maintaining endothelial and suppression of inflammatory markers; b) protection from sepsis in animal models; and c) direct antineoplastic effects, we propose the use of ascorbate as an adjuvant to existing modalities in the treatment and prevention of cancer-associated sepsis.
Collapse
Affiliation(s)
- Thomas E Ichim
- Department of Orthomolecular Studies, Riordan Clinic, 3100 N Hillside, Wichita, Kansas, 67210, USA
- Department of Regenerative Medicine, Medistem Inc, 9255 Towne Centre Drive, San Diego, California, 92121. USA
| | - Boris Minev
- Department of Medicine, Moores Cancer Center, University of California San Diego, 3855 Health Sciences Dr, San Diego, California, 92121, USA
| | - Todd Braciak
- Department of Regenerative Medicine, Medistem Inc, 9255 Towne Centre Drive, San Diego, California, 92121. USA
- Department of Immunology, Torrey Pines Institute for Molecular Studies, 3550 General Atomics Court, La Jolla, California,92121, USA
| | - Brandon Luna
- Department of Regenerative Medicine, Medistem Inc, 9255 Towne Centre Drive, San Diego, California, 92121. USA
| | - Ron Hunninghake
- Department of Orthomolecular Studies, Riordan Clinic, 3100 N Hillside, Wichita, Kansas, 67210, USA
| | - Nina A Mikirova
- Department of Orthomolecular Studies, Riordan Clinic, 3100 N Hillside, Wichita, Kansas, 67210, USA
| | - James A Jackson
- Department of Orthomolecular Studies, Riordan Clinic, 3100 N Hillside, Wichita, Kansas, 67210, USA
| | - Michael J Gonzalez
- Department of Human Development, Nutrition Program, University of Puerto Rico, Medical Sciences Campus, San Juan, 00936-5067, PR
| | - Jorge R Miranda-Massari
- Department of Pharmacy Practice, University of Puerto Rico, Medical Sciences Campus, School of Pharmacy, San Juan, 00936-5067, PR
| | - Doru T Alexandrescu
- Department of Experimental Studies, Georgetown Dermatology, 3301 New Mexico Ave, Washington DC, 20018, USA
| | - Constantin A Dasanu
- Department of Hematology and Oncology, University of Connecticut, 115 North Eagleville Road, Hartford, Connecticut, 06269, USA
| | - Vladimir Bogin
- Department of Regenerative Medicine, Medistem Inc, 9255 Towne Centre Drive, San Diego, California, 92121. USA
| | - Janis Ancans
- Department of Surgery, University of Latvia, 19 Raina Blvd, Riga, LV 1586, Latvia
| | - R Brian Stevens
- Department of Surgery, Microbiology, and Pathology, University of Nebraska Medical Center, 42nd and Emile, Omaha, Nebraska, 86198, USA
| | - Boris Markosian
- Department of Regenerative Medicine, Medistem Inc, 9255 Towne Centre Drive, San Diego, California, 92121. USA
| | - James Koropatnick
- Department of Microbiology and Immunology, and Department of Oncology, Lawson Health Research Institute and The University of Western Ontario, 1151 Richmond Street, London, Ontario, N2G 3M5, Canada
| | - Chien-Shing Chen
- School of Medicine, Division of Hematology and Oncology, Loma Linda University,24851 Circle Dr, Loma Linda, California, 92354, USA
| | - Neil H Riordan
- Department of Orthomolecular Studies, Riordan Clinic, 3100 N Hillside, Wichita, Kansas, 67210, USA
- Department of Regenerative Medicine, Medistem Inc, 9255 Towne Centre Drive, San Diego, California, 92121. USA
| |
Collapse
|
27
|
May JM, Qu ZC. Nitric oxide mediates tightening of the endothelial barrier by ascorbic acid. Biochem Biophys Res Commun 2010; 404:701-5. [PMID: 21156160 DOI: 10.1016/j.bbrc.2010.12.046] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Accepted: 12/08/2010] [Indexed: 11/29/2022]
Abstract
Vitamin C, or ascorbic acid, decreases paracellular endothelial permeability in a process that requires rearrangement of the actin cytoskeleton. To define the proximal mechanism of this effect, we tested whether it might involve enhanced generation and/or sparing of nitric oxide (NO) by the vitamin. EA.hy926 endothelial cells cultured on semi-porous filter supports showed decreased endothelial barrier permeability to radiolabeled inulin in response to exogenous NO provided by the NO donor spermine NONOATE, as well as to activation of the downstream NO pathway by 8-bromo-cyclic GMP, a cell-penetrant cyclic GMP analog. Inhibition of endothelial nitric oxide synthase (eNOS) with N(ω)-nitro-l-arginine methyl ester increased endothelial permeability, indicating a role constitutive NO generation by eNOS in maintaining the permeability barrier. Inhibition of guanylate cyclase by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one also increased endothelial permeability and blocked barrier tightening by spermine NONOATE. Loading cells with what are likely physiologic concentrations of ascorbate decreased endothelial permeability. This effect was blocked by inhibition of either eNOS or guanylate cyclase, suggesting that it involved generation of NO by eNOS and subsequent NO-dependent activation of guanylate cyclase. These results show that endothelial permeability barrier function depends on constitutive generation of NO and that ascorbate-dependent tightening of this barrier involves maintaining NO through the eNOS/guanylate cyclase pathway.
Collapse
Affiliation(s)
- James M May
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232-0475, USA.
| | | |
Collapse
|