Abstract
In order to ascertain the role of dietary flavonoids as antioxidants in vivo it is necessary to understand the chemical nature of the absorbed forms in the circulation in vivo and how the multiplicity of research findings in vitro reflect the bioactivity of flavonoids in vivo. Only when we gain adequate information on the circulating forms can we begin to understand the targeting to the tissues, whether flavonoids cross the blood-brain barrier, for example, and in what forms. Flavonoids are powerful antioxidants in vitro, but their overall function in vivo has yet to be clarified, whether antioxidant, anti-inflammatory, enzyme inhibitor, enzyme inducer, inhibitor of cell division, or some other role. It should also be emphasised that the reducing properties of flavonoids might contribute to redox regulation in cells, independently of their antioxidant properties, and thus might protect against cell ageing, for example, by working together with the intracellular reductant network. To gain understanding of these issues the factors influencing the absorption of flavonoids in the gastrointestinal tract needs to be established, namely the questions of: de-glycosylation before absorption, conjugation in the small intestine through glucuronidation, sulphation or methylation etc, metabolism and degradation in the colon to smaller phenolic molecules. The forms in which they circulate in vivo will influence their polarity and, thus, their localization and bioactivities in vivo. Finally if antioxidant activities are important, the elucidation of how such properties in vitro relate to the potential for conjugates and metabolites in vivo to act as antioxidants is required. The absorbed flavonoid components might function in the aqueous phase (like vitamin C) or in the lipophilic milieu (as vitamin E) in vivo. This will depend on their polarity properties on uptake, how they are metabolised on absorption, and their resulting structural forms in the circulation.
Keywords: Flavonoid Antioxidants, flavonoids cross, Flavonol, Flavanone, Anthocyanidin, Hydroxycinnamate, Coronary Heart Disease, ANTIOXIDANT, Quercetin
Current Medicinal Chemistry
Title: Flavonoid Antioxidants
Volume: 8 Issue: 7
Author(s): Catherine Rice-Evans
Affiliation:
Keywords: Flavonoid Antioxidants, flavonoids cross, Flavonol, Flavanone, Anthocyanidin, Hydroxycinnamate, Coronary Heart Disease, ANTIOXIDANT, Quercetin
Abstract: In order to ascertain the role of dietary flavonoids as antioxidants in vivo it is necessary to understand the chemical nature of the absorbed forms in the circulation in vivo and how the multiplicity of research findings in vitro reflect the bioactivity of flavonoids in vivo. Only when we gain adequate information on the circulating forms can we begin to understand the targeting to the tissues, whether flavonoids cross the blood-brain barrier, for example, and in what forms. Flavonoids are powerful antioxidants in vitro, but their overall function in vivo has yet to be clarified, whether antioxidant, anti-inflammatory, enzyme inhibitor, enzyme inducer, inhibitor of cell division, or some other role. It should also be emphasised that the reducing properties of flavonoids might contribute to redox regulation in cells, independently of their antioxidant properties, and thus might protect against cell ageing, for example, by working together with the intracellular reductant network. To gain understanding of these issues the factors influencing the absorption of flavonoids in the gastrointestinal tract needs to be established, namely the questions of: de-glycosylation before absorption, conjugation in the small intestine through glucuronidation, sulphation or methylation etc, metabolism and degradation in the colon to smaller phenolic molecules. The forms in which they circulate in vivo will influence their polarity and, thus, their localization and bioactivities in vivo. Finally if antioxidant activities are important, the elucidation of how such properties in vitro relate to the potential for conjugates and metabolites in vivo to act as antioxidants is required. The absorbed flavonoid components might function in the aqueous phase (like vitamin C) or in the lipophilic milieu (as vitamin E) in vivo. This will depend on their polarity properties on uptake, how they are metabolised on absorption, and their resulting structural forms in the circulation.
Export Options
About this article
Cite this article as:
Rice-Evans Catherine, Flavonoid Antioxidants, Current Medicinal Chemistry 2001; 8 (7) . https://dx.doi.org/10.2174/0929867013373011
DOI https://dx.doi.org/10.2174/0929867013373011 |
Print ISSN 0929-8673 |
Publisher Name Bentham Science Publisher |
Online ISSN 1875-533X |
Call for Papers in Thematic Issues
Advances in Medicinal Chemistry: From Cancer to Chronic Diseases.
The broad spectrum of the issue will provide a comprehensive overview of emerging trends, novel therapeutic interventions, and translational insights that impact modern medicine. The primary focus will be diseases of global concern, including cancer, chronic pain, metabolic disorders, and autoimmune conditions, providing a broad overview of the advancements in ...read more
Approaches to the treatment of chronic inflammation
Chronic inflammation is a hallmark of numerous diseases, significantly impacting global health. Although chronic inflammation is a hot topic, not much has been written about approaches to its treatment. This thematic issue aims to showcase the latest advancements in chronic inflammation treatment and foster discussion on future directions in this ...read more
Cellular and Molecular Mechanisms of Non-Infectious Inflammatory Diseases: Focus on Clinical Implications
The Special Issue covers the results of the studies on cellular and molecular mechanisms of non-infectious inflammatory diseases, in particular, autoimmune rheumatic diseases, atherosclerotic cardiovascular disease and other age-related disorders such as type II diabetes, cancer, neurodegenerative disorders, etc. Review and research articles as well as methodology papers that summarize ...read more
Chalcogen-modified nucleic acid analogues
Chalcogen-modified nucleosides, nucleotides and oligonucleotides have been of great interest to scientific research for many years. The replacement of oxygen in the nucleobase, sugar or phosphate backbone by chalcogen atoms (sulfur, selenium, tellurium) gives these biomolecules unique properties resulting from their altered physical and chemical properties. The continuing interest in ...read more
- Author Guidelines
- Graphical Abstracts
- Fabricating and Stating False Information
- Research Misconduct
- Post Publication Discussions and Corrections
- Publishing Ethics and Rectitude
- Increase Visibility of Your Article
- Archiving Policies
- Peer Review Workflow
- Order Your Article Before Print
- Promote Your Article
- Manuscript Transfer Facility
- Editorial Policies
- Allegations from Whistleblowers
- Announcements
Related Articles
-
Pharmacophore Modeling Methods in Focused Library Selection – Applications in the Context of a New Classification Scheme
Combinatorial Chemistry & High Throughput Screening Use of Double-source Computed Tomography for Evaluation of the Relationship Between Smoking and Coronary Plaques
Current Medical Imaging New Anti-Anginal Drugs: Ranolazine
Cardiovascular & Hematological Agents in Medicinal Chemistry Commercially Available, FDA-approved Epigenetic Modifiers As Therapeutic Agents in Bacterial Infection
Clinical Anti-Inflammatory & Anti-Allergy Drugs (Discontinued) Economic Evaluation in Paediatric Practice: Examples from Cardiac Critical Care
Current Pediatric Reviews Cytokines as Therapeutic Targets to Reduce Cardiovascular Risk in Chronic Inflammation
Current Pharmaceutical Design Strict Adherence to Guidelines in Decision Making for Coronary Angiography in Patients Who have Survived a Q Wave Myocardial Infarction; 2-Year Outcome in a Greek Population
Vascular Disease Prevention (Discontinued) Cerebral Amyloid Angiopathy-related Intracerebral Hemorrhage Score For Predicting Outcome
Current Neurovascular Research Therapeutic Potential and Pharmaceutical Applications of <i>Cucurbita</i>
Current Nutrition & Food Science Neurotrophins' Modulation by Olive Polyphenols
Current Medicinal Chemistry Glucose Tolerance: Hypothesis Testing on Malaysian Diabetic Community
Current Diabetes Reviews Critical Review of the Ankle Brachial Index
Current Cardiology Reviews Critical Determinants of Cardiovascular Risk in Rheumatoid Arthritis
Current Pharmaceutical Design Recent Advancements in Pharmacological Stent Therapy Using Polymeric Materials: Opportunities and Challenges
Current Drug Delivery Medial Temporal Lobe Volumes in Amnestic Mild Cognitive Impairment and Late-life Depression: Research Synthesis
Current Psychiatry Reviews Empagliflozin for Type 2 Diabetes Mellitus: An Overview of Phase 3 Clinical Trials
Current Diabetes Reviews P2Y12 Receptor Antagonists in Acute Coronary Syndrome: Clinical Implications of Pharmacologic and Pharmacogenetic Differences
Recent Patents on Cardiovascular Drug Discovery Cardiovascular Risk Factors in Chronic Inflammatory Rheumatic Diseases: Modern Assessment and Diagnosis
Current Vascular Pharmacology Serum Levels of IL-6, TNF-α and IL-10 as Early Predictors of Mortality in Trauma Hemorrhagic Shock Patients
Clinical Immunology, Endocrine & Metabolic Drugs (Discontinued) Aldose Reductase in Diabetic Microvascular Complications
Current Drug Targets