Effect of High-Dose Vitamin C on Hepatic Cytochrome P450 3A4 Activity

Heeswijk, Rolf P. G. van; Cooper, Curtis; Foster, Brian; Chauhan, Bobby M.; Shirazi, Farshad H.; Seguin, Isabelle; Phillips, Elizabeth; Mills, Ed

doi:10.1592/phco.2005.25.12.1725

Cited by 14 publications

(5 citation statements)

References 17 publications

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“…In addition to smoking, some dietary chemicals may regulate the catalytic activity of CYPs. For example, an increase of unsaturated fatty acids in food can enhance the expression of CYPs in the liver [ 80 ], and lacking protein, vitamin C, calcium, or magnesium in food may reduce the activity of CYPs in the process of metabolizing some drugs [ 81 , 82 , 83 ]. CYP3A can be induced by some brassicaceous vegetable, such as turnips and spinach, causing the enhancement of the first-pass effect of phenacetin [ 84 ].…”

Section: Individual Variation Of Cyp-mediated Drug Metabolismmentioning

confidence: 99%

Cytochrome P450 Enzymes and Drug Metabolism in Humans

Zhao

Ma²,

et al. 2021

IJMS

448

147

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Human cytochrome P450 (CYP) enzymes, as membrane-bound hemoproteins, play important roles in the detoxification of drugs, cellular metabolism, and homeostasis. In humans, almost 80% of oxidative metabolism and approximately 50% of the overall elimination of common clinical drugs can be attributed to one or more of the various CYPs, from the CYP families 1–3. In addition to the basic metabolic effects for elimination, CYPs are also capable of affecting drug responses by influencing drug action, safety, bioavailability, and drug resistance through metabolism, in both metabolic organs and local sites of action. Structures of CYPs have recently provided new insights into both understanding the mechanisms of drug metabolism and exploiting CYPs as drug targets. Genetic polymorphisms and epigenetic changes in CYP genes and environmental factors may be responsible for interethnic and interindividual variations in the therapeutic efficacy of drugs. In this review, we summarize and highlight the structural knowledge about CYPs and the major CYPs in drug metabolism. Additionally, genetic and epigenetic factors, as well as several intrinsic and extrinsic factors that contribute to interindividual variation in drug response are also reviewed, to reveal the multifarious and important roles of CYP-mediated metabolism and elimination in drug therapy.

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Section: Individual Variation Of Cyp-mediated Drug Metabolismmentioning

confidence: 99%

Cytochrome P450 Enzymes and Drug Metabolism in Humans

Zhao

Ma²,

et al. 2021

IJMS

448

147

View full text Add to dashboard Cite

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“…The different activities depend on the dosage used [89]. Vitamin C is a CYP inhibitor in vitro [90]. Similarly, quercetin has been shown to have the same activity of CYP inhibition [91].…”

Section: Pro-oxidant Activity Of Nutraceuticalsmentioning

confidence: 99%

Nutraceutical Boom in Cancer: Inside the Labyrinth of Reactive Oxygen Species

Calvani

Pasha

Favre

2020

IJMS

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In recent years, epidemiological studies have shown that food is a very powerful means for maintaining a state of well-being and for health prevention. Many degenerative, autoimmune and neoplastic diseases are related to nutrition and the nutrient–organism interaction could define the balance between health and disease. Nutrients and dietary components influence epigenetic phenomena and modify drugs response; therefore, these food–host interactions can influence the individual predisposition to disease and its potential therapeutic response. Do nutraceuticals have positive or negative effects during chemotherapy? The use of nutraceutical supplements in cancer patients is a controversial debate without a definitive conclusion to date. During cancer treatment, patients take nutraceuticals to alleviate drug toxicity and improve long-term results. Some nutraceuticals may potentiate the effect of cytotoxic chemotherapy by inducing cell growth arrest, cell differentiation, and alteration of the redox state of cells, but in some cases, high levels of them may interfere with the effectiveness of chemotherapy, making cancer cells less reactive to chemotherapy. In this review, we highlighted the emerging opinions and data on the pros and cons on the use of nutraceutical supplements during chemotherapy.

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“…A clinical study showed that vitamin C reduced plasma concentrations of a protease inhibitor (Slain et al, 2005), suggesting that vitamin C might affect CYP3A4‐activity. A modest induction of CYP3A was found when giving a high dose of vitamin C (500 mg twice/day), but the effect was only seen in male subjects (Van Heeswijk et al, 2005).…”

Section: Resultsmentioning

confidence: 99%

A systematic review of possible interactions for herbal medicines and dietary supplements used concomitantly with disease‐modifying or symptom‐alleviating multiple sclerosis drugs

Petersen

Bergien

2021

Phytotherapy Research

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Multiple Sclerosis (MS) is a demyelinating disease affecting the central nervous system, with no curative medicine available. The use of herbal drugs and dietary supplements is increasing among people with MS (PwMS), raising a need for knowledge about potential interactions between conventional MS medicine and herbal drugs/ dietary supplements. This systematic review provides information about the safety of simultaneous use of conventional MS-drugs and herbal drugs frequently used by PwMS. The study included 14 selected disease-modifying treatments and drugs frequently used for symptom-alleviation. A total of 129 published papers found via PubMed and Web of Science were reviewed according to defined inclusion-and exclusion criteria. Findings suggested that daily recommended doses of Panax ginseng and Ginkgo biloba should not be exceeded, and herbal preparations differing from standardized products should be avoided, especially when combined with anticoagulants or substrates of certain cytochrome P450 isoforms. Further studies are required regarding ginseng's ability to increase aspirin bioavailability. Combinations between chronic cannabis use and selective serotonin reuptake inhibitors or non-steroidal antiinflammatory drugs should be carefully monitored, whereas no significant evidence for drug-interactions between conventional MS-drugs and ginger, cranberry, vitamin D, fatty acids, turmeric, probiotics or glucosamine was found.

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Effect of High-Dose Vitamin C on Hepatic Cytochrome P450 3A4 Activity

Abstract: Sex and baseline CYP3A4 activity appeared to influence the effect of vitamin C on CYP3A4 activity.

Cited by 14 publications

References 17 publications

Cytochrome P450 Enzymes and Drug Metabolism in Humans

Cytochrome P450 Enzymes and Drug Metabolism in Humans

Nutraceutical Boom in Cancer: Inside the Labyrinth of Reactive Oxygen Species

A systematic review of possible interactions for herbal medicines and dietary supplements used concomitantly with disease‐modifying or symptom‐alleviating multiple sclerosis drugs

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