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Liu H, Zhang Y, Zhang H, Wang L, Wang T, Han Z, Wu L, Liu G. Effect of plasma vitamin C levels on Parkinson's disease and age at onset: a Mendelian randomization study. J Transl Med 2021; 19:221. [PMID: 34030714 PMCID: PMC8142636 DOI: 10.1186/s12967-021-02892-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 05/17/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Until now, epidemiological evidence regarding the association between vitamin C intake (both diet and supplements) and Parkinson's disease (PD) remains inconsistent. Hence, it is necessary to establish the causal link between vitamin C levels and PD, and further develop effective therapies or prevention. METHODS We selected 11 newly identified plasma vitamin C genetic variants from a large-scale plasma vitamin C GWAS dataset (n = 52,018) as the effective instrumental variables, and extracted their corresponding GWAS summary statistics from PD (33,674 PD cases and 449,056 controls) and PD age at onset (AAO) (n = 28,568). We then performed a Mendelian randomization (MR) study to evaluate the causal association of plasma vitamin C levels with PD and PD AAO using inverse-variance weighted (IVW), the weighted median, MR-Egger, and MR-PRESSO test. RESULTS We did not observe any significant association between genetically increased vitamin C levels and PD. Interestingly, we found a reduced trend of PD AAO (1.134 years) with 1 SD genetically increased vitamin C levels using IVW (beta = - 1.134, 95% CI: [- 2.515, 0.248], P = 0.108). Importantly, this trend was further successfully verified using both weighted median and MR-Egger. Each 1 SD genetically increased vitamin C levels could reduce PD AAO 1.75 and 2.592 years using weighted median (beta = - 1.750, 95% CI: [- 3.396, - 0.105], P = 0.037) and MR-Egger (beta = - 2.592, 95% CI: [- 4.623, - 0.560], P = 0.012). CONCLUSIONS We demonstrated the causal association between genetically increased plasma vitamin C levels and reduced PD AAO in people of European descent. Randomized controlled trials are required to clarify whether diet intake or supplement, or both could reduce the AAO of PD.
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Affiliation(s)
- Haijie Liu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
| | - Yan Zhang
- Department of Pathology, The Affiliated Hospital of Weifang Medical University, Weifang, 261053, China
| | - Haihua Zhang
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Longcai Wang
- Department of Anesthesiology, The Affiliated Hospital of Weifang Medical University, Weifang, 261053, China
| | - Tao Wang
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China.,Chinese Institute for Brain Research, Beijing, China
| | - Zhifa Han
- School of Medicine, School of Pharmaceutical Sciences, THU-PKU Center for Life Sciences, Tsinghua University, Beijing, China
| | - Liyong Wu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China.
| | - Guiyou Liu
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China. .,Chinese Institute for Brain Research, Beijing, China. .,Beijing Key Laboratory of Hypoxia Translational Medicine, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China. .,National Engineering Laboratory of Internet Medical Diagnosis and Treatment TechnologyXuanwu Hospital, Capital Medical University, Beijing, 100053, China.
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Wu H, Liu X, Gao ZY, Lin M, Zhao X, Sun Y, Pu XP. Icaritin Provides Neuroprotection in Parkinson's Disease by Attenuating Neuroinflammation, Oxidative Stress, and Energy Deficiency. Antioxidants (Basel) 2021; 10:antiox10040529. [PMID: 33805302 PMCID: PMC8066334 DOI: 10.3390/antiox10040529] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 03/24/2021] [Accepted: 03/26/2021] [Indexed: 12/17/2022] Open
Abstract
Neuroinflammation, oxidative stress, and mitochondrial dysfunction are all important pathogenic mechanisms underlying motor dysfunction and dopaminergic neuronal damage observed in patients with Parkinson’s disease (PD). However, despite extensive efforts, targeting inflammation and oxidative stress using various approaches has not led to meaningful clinical outcomes, and mitochondrial enhancers have also failed to convincingly achieve disease-modifying effects. We tested our hypothesis that treatment approaches in PD should simultaneously reduce neuroinflammation, oxidative stress, and improve alterations in neuronal energy metabolism using the flavonoid icaritin in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. Using matrix-assisted laser desorption/ionization–mass spectrometry imaging (MALDI-MSI), coupled with biochemical analyses and behavioral tests, we demonstrate that icaritin improves PD by attenuating the the NOD-like receptor family pyrin domain-containing protein 3 (NLRP3) inflammasome activity and stabilizing mitochondrial function, based on our extensive analyses showing the inhibition of NLRP3 inflammasome, reduction of NLRP3-mediated IL-1β secretion, and improvements in the levels of antioxidant molecules. Our data also indicated that icaritin stabilized the levels of proteins related to mitochondrial function, such as voltage-dependent anion channel (VDAC) and ATP synthase subunit beta (ATP5B), as well as those of molecules related to energy metabolism, such as ATP and ADP, ultimately improving mitochondrial dysfunction. By employing molecular docking, we also discovered that icaritin can interact with NLRP3, VDAC, ATP5B, and several blood–brain barrier (BBB)-related proteins. These data provide insights into the promising therapeutic potential of icaritin in PD.
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Affiliation(s)
- Hao Wu
- National Key Research Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China; (H.W.); (X.L.); (Z.-Y.G.); (M.L.); (X.Z.); (Y.S.)
- Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Xi Liu
- National Key Research Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China; (H.W.); (X.L.); (Z.-Y.G.); (M.L.); (X.Z.); (Y.S.)
- Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Ze-Yu Gao
- National Key Research Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China; (H.W.); (X.L.); (Z.-Y.G.); (M.L.); (X.Z.); (Y.S.)
- Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Ming Lin
- National Key Research Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China; (H.W.); (X.L.); (Z.-Y.G.); (M.L.); (X.Z.); (Y.S.)
- Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Xin Zhao
- National Key Research Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China; (H.W.); (X.L.); (Z.-Y.G.); (M.L.); (X.Z.); (Y.S.)
- Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Yi Sun
- National Key Research Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China; (H.W.); (X.L.); (Z.-Y.G.); (M.L.); (X.Z.); (Y.S.)
- Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Xiao-Ping Pu
- National Key Research Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China; (H.W.); (X.L.); (Z.-Y.G.); (M.L.); (X.Z.); (Y.S.)
- Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
- Correspondence: ; Tel.: +86-10-8280-2431
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3
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Abstract
The links between diet and Parkinson's disease (PD) are unclear and incomprehensible. However, numerous studies have demonstrated the correlation between diet, nutrients and health condition in PD patients. They indicate the possibility of management of the disease, which might be possible through nutrition. Pharmaceutical treatment as well as a complementary holistic approach to the patients should be considered. It is of critical importance to understand how the diet and nutrients might influence PD. A better understanding of the relationship between diet and PD could help to better manage the disease explain promising therapeutic approaches, minimize motor and nonmotor symptoms and disease progression based on a personalized diet. In this review, the recent literature on the observed nutrition disorders and the possible role of diet and nutrients in the prevention and potential regression of PD, as well as dietary interventions and supplementation used to manage the disease is revised.
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Affiliation(s)
- Paulina Gątarek
- Institute of General and Ecological Chemistry, Faculty of Chemistry, Lodz University of Technology, Lodz, Poland
| | - Joanna Kałużna-Czaplińska
- Institute of General and Ecological Chemistry, Faculty of Chemistry, Lodz University of Technology, Lodz, Poland
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4
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Lipid Peroxidation and Antioxidant Supplementation in Neurodegenerative Diseases: A Review of Human Studies. Antioxidants (Basel) 2020; 9:antiox9111128. [PMID: 33202952 PMCID: PMC7696060 DOI: 10.3390/antiox9111128] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/28/2020] [Accepted: 10/30/2020] [Indexed: 02/05/2023] Open
Abstract
Being characterized by progressive and severe damage in neuronal cells, neurodegenerative diseases (NDDs) are the major cause of disability and morbidity in the elderly, imposing a significant economic and social burden. As major components of the central nervous system, lipids play important roles in neural health and pathology. Disturbed lipid metabolism, particularly lipid peroxidation (LPO), is associated with the development of many NDDs, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis (ALS), all of which show elevated levels of LPO products and LPO-modified proteins. Thus, the inhibition of neuronal oxidation might slow the progression and reduce the severity of NDD; natural antioxidants, such as polyphenols and antioxidant vitamins, seem to be the most promising agents. Here, we summarize current literature data that were derived from human studies on the effect of natural polyphenols and vitamins A, C, and E supplementation in patients with AD, PD, and ALS. Although these compounds may reduce the severity and slow the progression of NDD, research gaps remain in antioxidants supplementation in AD, PD, and ALS patients, which indicates that further human studies applying antioxidant supplementation in different forms of NDDs are urgently needed.
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Spencer ES, Pitcher T, Veron G, Hannam T, MacAskill M, Anderson T, Dalrymple-Alford J, Carr AC. Positive Association of Ascorbate and Inverse Association of Urate with Cognitive Function in People with Parkinson's Disease. Antioxidants (Basel) 2020; 9:antiox9100906. [PMID: 32977491 PMCID: PMC7598173 DOI: 10.3390/antiox9100906] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/17/2020] [Accepted: 09/20/2020] [Indexed: 12/02/2022] Open
Abstract
Oxidative stress is thought to contribute to the aetiology of neurological disorders such as Parkinson’s disease. Ascorbate (vitamin C) is a potent antioxidant and is associated with neurological and cognitive function. In this study we assessed the ascorbate status of a cohort of people with Parkinson’s disease (n = 215), aged 50–90 years, compared with a cohort of age matched healthy controls (n = 48). The study sample’s cognitive status ranged from normal to mild cognitive impairment and dementia. There was no difference between the Parkinson’s disease and healthy control groups with respect to mean ascorbate status, however, a higher proportion of participants with Parkinson’s disease had hypovitaminosis C (i.e., <23 μmol/L) compared with healthy controls (20% vs. 8%, respectively). Within the Parkinson’s disease group, Montreal Cognitive Assessment (MoCA) scores correlated positively with ascorbate concentrations, with higher ascorbate status associated with better cognitive function (r = 0.14, p = 0.045). Participants with hypovitaminosis C had significantly lower MoCA scores relative to participants with ascorbate concentrations >23 µmol/L (p = 0.014). Ascorbate concentrations were significantly lower in the cognitively impaired subgroup compared with the normal cognition subgroup in the Parkinson’s disease cohort (p = 0.03). In contrast, urate showed an inverse correlation with cognitive function (r = −0.19, p = 0.007), with higher urate concentrations observed in the cognitively impaired subgroup compared with the normal cognition subgroup (p = 0.015). There was an inverse association between ascorbate status and urate concentrations (r = −0.15, p = 0.017). Plasma protein carbonyls, a measure of systemic oxidative stress, were not significantly different between the Parkinson’s disease cohort and healthy controls, and there was no association with cognitive function (r = 0.09, p = 0.19) or with ascorbate status (r = −0.05, p = 0.45). Overall, our study showed ascorbate status was positively associated with cognitive function in Parkinson’s disease, suggesting that longitudinal studies investigating the temporal sequence of cognitive decline and ascorbate status are warranted.
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Affiliation(s)
- Emma S. Spencer
- Nutrition in Medicine Research Group, Department of Pathology and Biomedical Science, University of Otago, Christchurch 8011, New Zealand;
| | - Toni Pitcher
- Department of Medicine, University of Otago, Christchurch 8011, New Zealand; (T.P.); (M.M.); (T.A.); (J.D.-A.)
- New Zealand Brain Research Institute, Christchurch 8011, New Zealand
| | - Gabriel Veron
- Centre for Postgraduate Nursing Studies, University of Otago, Christchurch 8011, New Zealand; (G.V.); (T.H.)
| | - Tracey Hannam
- Centre for Postgraduate Nursing Studies, University of Otago, Christchurch 8011, New Zealand; (G.V.); (T.H.)
| | - Michael MacAskill
- Department of Medicine, University of Otago, Christchurch 8011, New Zealand; (T.P.); (M.M.); (T.A.); (J.D.-A.)
- New Zealand Brain Research Institute, Christchurch 8011, New Zealand
| | - Tim Anderson
- Department of Medicine, University of Otago, Christchurch 8011, New Zealand; (T.P.); (M.M.); (T.A.); (J.D.-A.)
- New Zealand Brain Research Institute, Christchurch 8011, New Zealand
| | - John Dalrymple-Alford
- Department of Medicine, University of Otago, Christchurch 8011, New Zealand; (T.P.); (M.M.); (T.A.); (J.D.-A.)
- New Zealand Brain Research Institute, Christchurch 8011, New Zealand
- School of Psychology, Speech, and Hearing, University of Canterbury, Christchurch 8140, New Zealand
| | - Anitra C. Carr
- Nutrition in Medicine Research Group, Department of Pathology and Biomedical Science, University of Otago, Christchurch 8011, New Zealand;
- Correspondence: ; Tel.: +64-3364-0649
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7
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Wang M, Liu Z, Sun W, Yuan Y, Jiao B, Zhang X, Shen L, Jiang H, Xia K, Tang B, Wang J. Association Between Vitamins and Amyotrophic Lateral Sclerosis: A Center-Based Survey in Mainland China. Front Neurol 2020; 11:488. [PMID: 32625160 PMCID: PMC7314934 DOI: 10.3389/fneur.2020.00488] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 05/04/2020] [Indexed: 12/12/2022] Open
Abstract
To date, conflicting results about the role of vitamins in amyotrophic lateral sclerosis (ALS) have been reported along with a lack of systematic studies on all types of serum vitamins in patients with ALS. Moreover, extensive studies have been conducted on vitamins in other neurodegenerative diseases; however, whether serum vitamin alterations in ALS are similar to those in other neurodegenerative diseases remains unclear. Therefore, we performed a study involving a large Chinese cohort of patients with ALS to address this gap. In this study, 202 patients with ALS, 214 with a neurodegenerative disease that mimicked ALS (mimics), and 208 healthy controls were enrolled. Serum vitamins of all subjects were examined under fasting state in Clinical Laboratory. As a result, we found that higher vitamin A and E levels and lower vitamin B2, B9, and C levels were in patients with ALS compared to healthy controls, and that high vitamin A and E levels, and low vitamin B2, B9, and C levels were associated with an increased risk for ALS. In addition, serum vitamin C was lower in early-onset ALS patients compared to those in late-onset ALS patients; however, there was no significant correlation between serum vitamins and age at onset, sites at onset, disease duration, or disease severity of ALS. We also found that patients with ALS showed similar vitamin alterations to mimics, with the exception of vitamin E. In summary, our study adds information to the literature on the role of vitamins in ALS and provides support for clinical guidance regarding dietary changes and vitamin supplements in patients with ALS.
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Affiliation(s)
- Mengli Wang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Zhen Liu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Weining Sun
- General Practice, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Yanchun Yuan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Bin Jiao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Xuewei Zhang
- Health Management Center, Xiangya Hospital, Central South University, Changsha, China
| | - Lu Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- Laboratory of Medical Genetics, Central South University, Changsha, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, China
| | - Hong Jiang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- Laboratory of Medical Genetics, Central South University, Changsha, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, China
| | - Kun Xia
- Laboratory of Medical Genetics, Central South University, Changsha, China
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- Laboratory of Medical Genetics, Central South University, Changsha, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, China
| | - Junling Wang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- Laboratory of Medical Genetics, Central South University, Changsha, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, China
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8
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Moretti M, Rodrigues ALS. Ascorbic acid as an antioxidant and applications to the central nervous system. Pathology 2020. [DOI: 10.1016/b978-0-12-815972-9.00015-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ballaz SJ, Rebec GV. Neurobiology of vitamin C: Expanding the focus from antioxidant to endogenous neuromodulator. Pharmacol Res 2019; 146:104321. [PMID: 31229562 DOI: 10.1016/j.phrs.2019.104321] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/16/2019] [Accepted: 06/18/2019] [Indexed: 01/06/2023]
Abstract
Ascorbic acid (AA) is a water-soluble vitamin (C) found in all bodily organs. Most mammals synthesize it, humans are required to eat it, but all mammals need it for healthy functioning. AA reaches its highest concentration in the brain where both neurons and glia rely on tightly regulated uptake from blood via the glucose transport system and sodium-coupled active transport to accumulate and maintain AA at millimolar levels. As a prototype antioxidant, AA is not only neuroprotective, but also functions as a cofactor in redox-coupled reactions essential for the synthesis of neurotransmitters (e.g., dopamine and norepinephrine) and paracrine lipid mediators (e.g., epoxiecoisatrienoic acids) as well as the epigenetic regulation of DNA. Although redox capacity led to the promotion of AA in high doses as potential treatment for various neuropathological and psychiatric conditions, ample evidence has not supported this therapeutic strategy. Here, we focus on some long-neglected aspects of AA neurobiology, including its modulatory role in synaptic transmission as demonstrated by the long-established link between release of endogenous AA in brain extracellular fluid and the clearance of glutamate, an excitatory amino acid. Evidence that this link can be disrupted in animal models of Huntington´s disease is revealing opportunities for new research pathways and therapeutic applications (e.g., epilepsy and pain management). In fact, we suggest that improved understanding of the regulation of endogenous AA and its interaction with key brain neurotransmitter systems, rather than administration of AA in excess, should be the target of future brain-based therapies.
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Affiliation(s)
- Santiago J Ballaz
- School of Biological Sciences and Engineering, Yachay Tech University, Urcuqui, Ecuador.
| | - George V Rebec
- Program in Neuroscience, Department Psychological & Brain Sciences, Indiana University, Bloomington, USA.
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Benefits of Vitamins in the Treatment of Parkinson's Disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:9426867. [PMID: 30915197 PMCID: PMC6402202 DOI: 10.1155/2019/9426867] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 02/04/2019] [Indexed: 12/15/2022]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease in the elderly, which is clinically characterized by bradykinesia, resting tremor, abnormal posture balance, and hypermyotonia. Currently, the pathogenic mechanism of PD remains unclear. Numerous clinical studies as well as animal and cell experiments have found a certain relationship between the vitamin family and PD. The antioxidant properties of vitamins and their biological functions of regulating gene expression may be beneficial for the treatment of PD. Current clinical evidence indicates that proper supplementation of various vitamins can reduce the incidence of PD in the general population and improve the clinical symptoms of patients with PD; nevertheless, the safety of regular vitamin supplements still needs to be highlighted. Vitamin supplementation may be an effective adjuvant treatment for PD. In this review, we summarized the biological correlations between vitamins and PD as well as the underlying pathophysiological mechanisms. Additionally, we elaborated the therapeutic potentials of vitamins for PD.
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Moretti M, Fraga DB, Rodrigues ALS. Preventive and therapeutic potential of ascorbic acid in neurodegenerative diseases. CNS Neurosci Ther 2017; 23:921-929. [PMID: 28980404 DOI: 10.1111/cns.12767] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 09/19/2017] [Accepted: 09/19/2017] [Indexed: 12/17/2022] Open
Abstract
In this review, we summarize the involvement of ascorbic acid in neurodegenerative diseases by presenting available evidence on the behavioral and biochemical effects of this compound in animal models of neurodegeneration as well as the use of ascorbic acid as a therapeutic approach to alleviate neurodegenerative progression in clinical studies. Ascorbate, a reduced form of vitamin C, has gained interest for its multiple functions and mechanisms of action, contributing to the homeostasis of normal tissues and organs as well as to tissue regeneration. In the brain, ascorbate exerts neuromodulatory functions and scavenges reactive oxygen species generated during synaptic activity and neuronal metabolism. These are important properties as redox imbalance and abnormal protein aggregation constitute central mechanisms implicated in the pathogenesis of neurodegenerative diseases, including Alzheimer's, Parkinson's, and Huntington's diseases, multiple sclerosis, and amyotrophic lateral sclerosis. Indeed, several studies have indicated an association between low serum ascorbate concentrations and neurodegeneration. Moreover, ascorbic acid is a suitable candidate for supplying either antioxidant defense or modulation of neuronal and astrocytic metabolism under neurodegenerative conditions. Ascorbic acid acts mainly by decreasing oxidative stress and reducing the formation of protein aggregates, which may contribute to the reduction of cognitive and/or motor impairments observed in neurodegenerative processes. Although several studies support a possible role of ascorbic acid administration against neurodegeneration, more researches are essential to substantiate the existing results and accelerate the knowledge in this field.
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Affiliation(s)
- Morgana Moretti
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Daiane Bittencourt Fraga
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Ana Lúcia S Rodrigues
- Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil
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12
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Abstract
Oxidative stress has been implicated as a core contributor to the initiation and progression of multiple neurological diseases. Genetic and environmental factors can produce oxidative stress through mitochondrial dysfunction leading to the degeneration of dopaminergic and other neurons underlying Parkinson disease (PD). Although clinical trials of antioxidants have thus far failed to demonstrate slowed progression of PD, oxidative stress remains a compelling target. Rather than prompting abandonment of antioxidant strategies, these failures have raised the bar for justifying drug and dosing selections and for improving study designs to test for disease modification by antioxidants. Urate, the main antioxidant found in plasma as well as the end product of purine metabolism in humans, has emerged as a promising potential neuroprotectant with advantages that distinguish it from previously tested antioxidant agents. Uniquely, higher urate levels in plasma or cerebrospinal fluid (CSF) have been linked to both a lower risk of developing PD and to a slower rate of its subsequent progression in numerous large prospective epidemiological and clinical cohorts. Laboratory evidence that urate confers neuroprotection in cellular and animal models of PD, possibly via the Nrf2 antioxidant response pathway, further strengthened its candidacy for rapid clinical translation. An early phase trial of the urate precursor inosine demonstrated its capacity to safely produce well tolerated, long-term elevation of plasma and CSF urate in early PD, supporting a phase 3 trial now underway to determine whether oral inosine dosed to elevate urate to concentrations predictive of favorable prognosis in PD slows clinical decline in people with recently diagnosed, dopamine transporter-deficient PD.
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Affiliation(s)
- Grace F Crotty
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.
| | - Alberto Ascherio
- Departments of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA, USA
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Seidl SE, Potashkin JA. The promise of neuroprotective agents in Parkinson's disease. Front Neurol 2011; 2:68. [PMID: 22125548 PMCID: PMC3221408 DOI: 10.3389/fneur.2011.00068] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 10/21/2011] [Indexed: 02/04/2023] Open
Abstract
Parkinson’s disease (PD) is characterized by loss of dopamine neurons in the substantia nigra of the brain. Since there are limited treatment options for PD, neuroprotective agents are currently being tested as a means to slow disease progression. Agents targeting oxidative stress, mitochondrial dysfunction, and inflammation are prime candidates for neuroprotection. This review identifies Rasagiline, Minocycline, and creatine, as the most promising neuroprotective agents for PD, and they are all currently in phase III trials. Other agents possessing protective characteristics in delaying PD include stimulants, vitamins, supplements, and other drugs. Additionally, combination therapies also show benefits in slowing PD progression. The identification of neuroprotective agents for PD provides us with therapeutic opportunities for modifying the course of disease progression and, perhaps, reducing the risk of onset when preclinical biomarkers become available.
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Affiliation(s)
- Stacey E Seidl
- Department of Biological Sciences, DePaul University Chicago, IL, USA
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14
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Wirdefeldt K, Adami HO, Cole P, Trichopoulos D, Mandel J. Epidemiology and etiology of Parkinson's disease: a review of the evidence. Eur J Epidemiol 2011; 26 Suppl 1:S1-58. [PMID: 21626386 DOI: 10.1007/s10654-011-9581-6] [Citation(s) in RCA: 724] [Impact Index Per Article: 55.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 04/05/2011] [Indexed: 12/14/2022]
Abstract
The etiology of Parkinson's disease (PD) is not well understood but likely to involve both genetic and environmental factors. Incidence and prevalence estimates vary to a large extent-at least partly due to methodological differences between studies-but are consistently higher in men than in women. Several genes that cause familial as well as sporadic PD have been identified and familial aggregation studies support a genetic component. Despite a vast literature on lifestyle and environmental possible risk or protection factors, consistent findings are few. There is compelling evidence for protective effects of smoking and coffee, but the biologic mechanisms for these possibly causal relations are poorly understood. Uric acid also seems to be associated with lower PD risk. Evidence that one or several pesticides increase PD risk is suggestive but further research is needed to identify specific compounds that may play a causal role. Evidence is limited on the role of metals, other chemicals and magnetic fields. Important methodological limitations include crude classification of exposure, low frequency and intensity of exposure, inadequate sample size, potential for confounding, retrospective study designs and lack of consistent diagnostic criteria for PD. Studies that assessed possible shared etiological components between PD and other diseases show that REM sleep behavior disorder and mental illness increase PD risk and that PD patients have lower cancer risk, but methodological concerns exist. Future epidemiologic studies of PD should be large, include detailed quantifications of exposure, and collect information on environmental exposures as well as genetic polymorphisms.
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Affiliation(s)
- Karin Wirdefeldt
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
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Tan DX, Manchester LC, Sainz R, Mayo JC, Alvares FL, Reiter RJ. Antioxidant strategies in protection against neurodegenerative disorders. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.13.10.1513] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Buhmann C, Arlt S, Kontush A, Möller-Bertram T, Sperber S, Oechsner M, Stuerenburg HJ, Beisiegel U. Plasma and CSF markers of oxidative stress are increased in Parkinson's disease and influenced by antiparkinsonian medication. Neurobiol Dis 2004; 15:160-70. [PMID: 14751781 DOI: 10.1016/j.nbd.2003.10.003] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We determined systemic oxidative stress in Parkinson's disease (PD) patients, patients with other neurological diseases (OND) and healthy controls by measurement of in vitro lipoprotein oxidation and levels of hydro- and lipophilic antioxidants in plasma and cerebrospinal fluid (CSF). Additionally, we investigated the influence of levodopa (LD) and dopamine agonist therapy (DA) on the oxidative status in PD patients. We found increased oxidative stress, seen as higher levels of lipoprotein oxidation in plasma and CSF, decrease of plasma levels of protein sulfhydryl (SH) groups and lower CSF levels of alpha-tocopherol in PD patients compared to OND patients and controls. Levodopa treatment did not significantly change the plasma lipoprotein oxidation but LD monotherapy tended to result in an increase of autooxidation and in a decrease of plasma antioxidants with significance for ubiquinol-10. DA monotherapy was significantly associated with higher alpha-tocopherol levels. Patients with DA monotherapy or co-medication with DA showed a trend to lower lipoprotein oxidation. These data support the concept of oxidative stress as a factor in the pathogenesis of PD and might be an indicator of a potential prooxidative role of LD and a possible antioxidative effect of DA in PD treatment.
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Affiliation(s)
- Carsten Buhmann
- Neurological Department, University Clinic Hamburg-Eppendorf, D-20246 Hamburg, Germany.
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Paraskevas GP, Kapaki E, Petropoulou O, Anagnostouli M, Vagenas V, Papageorgiou C. Plasma levels of antioxidant vitamins C and E are decreased in vascular parkinsonism. J Neurol Sci 2004; 215:51-5. [PMID: 14568128 DOI: 10.1016/s0022-510x(03)00184-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Oxidative stress is an important mechanism of cell death in Parkinson's disease (PD) and brain ischemia. Vitamins C, E and A are important antioxidants and deficiency of these agents has been implicated in the mechanisms of atherosclerosis. We measured the levels of the above antioxidant vitamins in 44 patients with PD, 12 patients with vascular parkinsonism (VP), 11 patients with other parkinsonism syndromes of various causes and 39 controls. Vitamin A levels did not differ between groups. Vitamins C and E were found decreased in VP, while they were normal in PD indicating low levels of antioxidant vitamins in VP and stressing the necessity of maintaining sufficient dietary intake of these agents in the elderly.
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Affiliation(s)
- George P Paraskevas
- Department of Neurology, Athens National University, Medical School, Aeginition Hospital, 74 Vas. Sophias Avenue, 11528 Athens, Greece
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Ehrhart J, Zeevalk GD. Cooperative interaction between ascorbate and glutathione during mitochondrial impairment in mesencephalic cultures. J Neurochem 2003; 86:1487-97. [PMID: 12950457 DOI: 10.1046/j.1471-4159.2003.01954.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A decrease in total glutathione, and aberrant mitochondrial bioenergetics have been implicated in the pathogenesis of Parkinson's disease. Our previous work exemplified the importance of glutathione (GSH) in the protection of mesencephalic neurons exposed to malonate, a reversible inhibitor of mitochondrial succinate dehydrogenase/complex II. Additionally, reactive oxygen species (ROS) generation was an early, contributing event in malonate toxicity. Protection by ascorbate was found to correlate with a stimulated increase in protein-glutathione mixed disulfide (Pr-SSG) levels. The present study further examined ascorbate-glutathione interactions during mitochondrial impairment. Depletion of GSH in mesencephalic cells with buthionine sulfoximine potentiated both the malonate-induced toxicity and generation of ROS as monitored by dichlorofluorescein diacetate (DCF) fluorescence. Ascorbate completely ameliorated the increase in DCF fluorescence and toxicity in normal and GSH-depleted cultures, suggesting that protection by ascorbate was due in part to upstream removal of free radicals. Ascorbate stimulated Pr-SSG formation during mitochondrial impairment in normal and GSH-depleted cultures to a similar extent when expressed as a proportion of total GSH incorporated into mixed disulfides. Malonate increased the efflux of GSH and GSSG over time in cultures treated for 4, 6 or 8 h. The addition of ascorbate to malonate-treated cells prevented the efflux of GSH, attenuated the efflux of GSSG and regulated the intracellular GSSG/GSH ratio. Maintenance of GSSG/GSH with ascorbate plus malonate was accompanied by a stimulation of Pr-SSG formation. These findings indicate that ascorbate contributes to the maintenance of GSSG/GSH status during oxidative stress through scavenging of radical species, attenuation of GSH efflux and redistribution of GSSG to the formation of mixed disulfides. It is speculated that these events are linked by glutaredoxin, an enzyme shown to contain both dehydroascorbate reductase as well as glutathione thioltransferase activities.
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Affiliation(s)
- Julie Ehrhart
- Department of Neurology, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway, New Jersey, USA
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Formichi P, Battisti C, Dotti MT, Hayek G, Zappella M, Federico A. Vitamin E serum levels in Rett syndrome. J Neurol Sci 1998; 156:227-30. [PMID: 9588862 DOI: 10.1016/s0022-510x(98)00035-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In order to study the role of vitamin E in the pathogenesis of Rett syndrome (RS), we analysed vitamin E serum levels in twenty-eight patients affected by this disorder. We found lower vitamin E serum levels in nine cases (32.1%). These results indicated that the oxidative free radical metabolism may be impaired in a significant percentage of Rett syndrome patients suggesting the need for further studies of tissue vitamin E in different brain regions.
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Affiliation(s)
- P Formichi
- Institute of Neurological Sciences, University of Siena, Policlinico Le Scotte, Italy
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21
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Veldman BA, Wijn AM, Knoers N, Praamstra P, Horstink MW. Genetic and environmental risk factors in Parkinson's disease. Clin Neurol Neurosurg 1998; 100:15-26. [PMID: 9637199 DOI: 10.1016/s0303-8467(98)00009-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Parkinson's disease (PD) is a multifactorial disorder, caused by a combination of age, genetics and environmental factors. Nigral cells are susceptible to multiple causes of derangement of normal cell function, all of which may contribute to the same Parkinson phenotype. Autosomal dominant alpha-synuclein-gene PD represents one of the pure genetic forms, whereas cases of sporadic PD probably depend more on age and environmental factors, MPTP-Parkinsonism being the purest example of an environmentally caused Parkinson phenotype. This review suggests that pesticides-herbicides, smoking and head trauma probably represent the most eligible candidates for environmental factors involved in provoking PD or influencing its natural course.
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Affiliation(s)
- B A Veldman
- Department of Neurology, University Hospital Nijmegen, The Netherlands
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23
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Affiliation(s)
- H Boeing
- German Institute of Human Nutrition Potsdam-Rehbrücke, Bergholz-Rehbrücke, Germany
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Bode AM. Metabolism of vitamin C in health and disease. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 1996; 38:21-47. [PMID: 8895802 DOI: 10.1016/s1054-3589(08)60977-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- A M Bode
- Physiology Department School of Medicine and Health Sciences, University of North Dakota, Grand Forks 58201, USA
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Barabás J, Nagy E, Degrell I. Ascorbic acid in cerebrospinal fluid — a possible protection against free radicals in the brain. Arch Gerontol Geriatr 1995; 21:43-8. [PMID: 15374223 DOI: 10.1016/0167-4943(95)00654-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/1995] [Revised: 04/10/1995] [Accepted: 04/11/1995] [Indexed: 11/24/2022]
Abstract
The function of ascorbic acid in living organisms is complex. Previous studies emphasize its protective role against harmful effect of free radicals, and its presence is necessary for the function of numerous enzymes. Ascorbic acid is a powerful reducing agent due to its dienol molecular structure, which is not present in the oxidized form, dehydroascorbic acid. The ratio of ascorbic acid and dehydroascorbic acid might be a marker of oxidative-reductive processes. We measured and compared the level of ascorbic acid and dehydroascorbic acid in the plasma of healthy persons and those of senile dementia patients, who represent pathological aging of the brain. In senile dementia patients, ascorbic acid and dehydroascorbic acid levels were also measured in the cerebrospinal fluid. Concentrations were determined by high performance liquid chromatography with electrochemical detection. In the plasma of senile dementia patients, very low ascorbic acid levels were found (ca. 30% of the healthy control). In lumbar cerebrospinal fluid, the concentration of ascorbic acid is 2.7 times higher compared to that of the plasma level. After intravenous infusion of ascorbic acid, a slow but marked increase of the concentration in the cerebrospinal fluid was measured. Our results support an active transport process for ascorbic acid through the blood-CSF barrier. Ascorbic acid level might be an important factor representing the protection of the central nervous system against free radicals.
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Affiliation(s)
- J Barabás
- Department of Psychiatry, University of Debrecen Medical School, Debrecen, Nagyerdei krt. 98., 4012 Hungary
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Cabrera-Valdivia F, Jiménez-Jiménez FJ, Molina JA, Férnandez-Calle P, Vázquez A, Cañizares-Liébana F, Larumbe-Lobalde S, Ayuso-Peralta L, Rabasa M, Codoceo R. Peripheral iron metabolism in patients with Parkinson's disease. J Neurol Sci 1994; 125:82-6. [PMID: 7964893 DOI: 10.1016/0022-510x(94)90246-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
To elucidate the possible role of peripheral metabolism of iron in the risk for developing Parkinson's disease (PD), we compared serum levels of iron, transferrin and ferritin, and 24-h iron excretion in urine after a single intramuscular dose of 1 mg/kg desferrioxamine, in 68 PD patients and their spouses as the control group. All these values did not differ significantly between the groups, they were not influenced by antiparkinsonian therapy, and they did not correlate with age, age at onset and duration of the disease, scores of the Unified PD Rating Scale or the Hoehn and Yahr staging in the PD group, with the exception of the 24-h urinary iron excretion with the duration of the disease (r = 0.32, p < 0.05). These results suggest that peripheral metabolism of iron is apparently unrelated to the risk of developing PD.
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Affiliation(s)
- F Cabrera-Valdivia
- Department of Neurology, Hospital Universitario Príncipe de Asturias Alcalá de Henares, Madrid, Spain
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27
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Beyer RE. The role of ascorbate in antioxidant protection of biomembranes: interaction with vitamin E and coenzyme Q. J Bioenerg Biomembr 1994; 26:349-58. [PMID: 7844109 DOI: 10.1007/bf00762775] [Citation(s) in RCA: 238] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
One of the vital roles of ascorbic acid (vitamin C) is to act as an antioxidant to protect cellular components from free radical damage. Ascorbic acid has been shown to scavenge free radicals directly in the aqueous phases of cells and the circulatory system. Ascorbic acid has also been proven to protect membrane and other hydrophobic compartments from such damage by regenerating the antioxidant form of vitamin E. In addition, reduced coenzyme Q, also a resident of hydrophobic compartments, interacts with vitamin E to regenerate its antioxidant form. The mechanism of vitamin C antioxidant function, the myriad of pathologies resulting from its clinical deficiency, and the many health benefits it provides, are reviewed.
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Affiliation(s)
- R E Beyer
- Department of Biology, University of Michigan, Ann Arbor 48109
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Fernández-Calle P, Jiménez-Jiménez F, Molina J, Cabrera-Valdivia F, Vázquez A, Urra D, Bermejo F, Matallana M, Codoceo R. Serum levels of ascorbic acid (vitamin C) in humans: response to the letter by K. Dabrowski (J. Neurol. Sci., 124 (1994) 113). J Neurol Sci 1994. [DOI: 10.1016/0022-510x(94)90020-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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29
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Dabrowski K. Serum levels of ascorbic acid (vitamin C) in humans. J Neurol Sci 1994; 124:113-4. [PMID: 7931413 DOI: 10.1016/0022-510x(94)90019-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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30
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Jiménez-Jiménez FJ, Molina JA, Fernández-Calle P, Vázquez A, Cabrera-Valdivia F, Catalán MJ, García-Albea E, Bermejo F, Codoceo R. Serum levels of beta-carotene and other carotenoids in Parkinson's disease. Neurosci Lett 1993; 157:103-6. [PMID: 8233018 DOI: 10.1016/0304-3940(93)90653-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To elucidate the possible role of carotenoids in the risk for developing Parkinson's disease (PD), we compared serum levels of beta-carotene, alpha-carotene and lycopene, measured by high performance liquid chromatography, of 61 PD patients using their spouses as the control group. The serum levels of these 3 carotenoids did not differ significantly between PD patients and control groups. There was no influence of antiparkinsonian therapy on serum carotenoids levels, and these did not correlate with age, age at onset, scores of the Unified Parkinson Disease Rating Scale or the Hoehn and Yahr staging in the PD group. These results show that serum carotenoids concentrations are apparently unrelated to the risk for developing PD.
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Affiliation(s)
- F J Jiménez-Jiménez
- Department of Neurology, Hospital Universitario, Príncipe de Asturias-Alcalá de Henares, Spain
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