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Reduction in hypericin-induced phototoxicity by Hypericum perforatum extracts and pure compounds

Paper ID Volume ID Publish Year Pages File Format Full-Text
30568 44487 2006 13 PDF Available
Title
Reduction in hypericin-induced phototoxicity by Hypericum perforatum extracts and pure compounds
Abstract

Clinical evidence suggests that administration of Hypericum perforatum (Hp) extracts containing the photo-activated hypericin compounds may cause fewer skin photosensitization reactions than administration of pure hypericin. This study was conducted to determine whether the phototoxicity of hypericin in HaCaT keratinocytes could be attenuated by H. perforatum extracts and constituents. Two extracts, when supplemented with 20 μM hypericin: (1) an ethanol re-extraction of residue following a chloroform extraction (denoted ethanol(-chloroform)) (3.35 μM hypericin and 124.0 μM total flavonoids); and (2) a chloroform extract (hypericin and flavonoids not detected), showed 25% and 50% (p < 0.0001) less phototoxicity than 20 μM hypericin alone. Two H. perforatum constituents, when supplemented with 20 μM hypericin: (1) 10 μM chlorogenic acid; and (2) 0.25 μM pyropheophorbide, exhibited 24% (p < 0.05) and 40% (p < 0.05) less phototoxicity than 20 μM hypericin alone. The peroxidation of arachidonic acid was assessed as a measure of oxidative damage by photo-activated hypericin, but this parameter of lipid peroxidation was not influenced by the extracts or constituents. However α-tocopherol, a known antioxidant also did not influence the amount of lipid peroxidation induced in this system. These observations indicate that hypericin combined with H. perforatum extracts or constituents may exert less phototoxicity than pure hypericin, but possibly not through a reduction in arachidonic acid peroxidation.

Keywords
Hypericum perforatum; St. John’s Wort; HaCaT keratinocytes; Hypericin; Lipid peroxidation; Phototoxicity
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Reduction in hypericin-induced phototoxicity by Hypericum perforatum extracts and pure compounds
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Publisher
Database: Elsevier - ScienceDirect
Journal: Journal of Photochemistry and Photobiology B: Biology - Volume 85, Issue 2, 1 November 2006, Pages 118–130
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us