Abstract：
:Hypericin is a naturally occurring photosensitizer, whose presence in plants has been responsible for cutaneous phototoxicity in grazing animals. The photosensitizing properties of this agent have recently been exploited in models for anti-tumor and anti-viral activity. The cytotoxicity of hypericin and light was assessed in 3T3 mouse fibroblasts using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide)] assay and the lactate dehydrogenase (LDH) leakage assay. Membrane damage was assessed in swine erythrocytes using hemolysis, potassium (K+) leakage and formation of lipid hydroperoxides. Concentration- and light-dependent decreases in fibroblast viability were seen starting at hypericin concentrations of 1.25 microM and light power flux levels of 24 J/cm2 using a visible light source and at 0.417 microM hypericin and a similar light dose using a solar simulator. No LDH leakage was observed at hypericin concentrations up to 30 microM and visible light up to 144 J/cm2. Light-and/or concentration-dependent increases in hemolysis, K+ leakage and formation of lipid hydroperoxides in red blood cell (RBC) membranes were observed, but at concentrations and light doses much greater than those required to induce cytotoxicity in fibroblasts. Lipid peroxidation and hemolysis occurred at 15 microM hypericin and 24 J/cm2 (visible light source). Potassium ion leakage occurred at concentrations and light levels as low as 5 microM and 12 J/cm2 or 15 microM and 4.8 J/cm2 (visible light source) but was still a less sensitive indicator than fibroblast cytotoxicity. Evidence for both type I and type II reactions was shown in RBC membranes by TLC analysis of cholesterol products. In the absence of light, hypericin appears to be relatively nontoxic in the models tested.
journal_name
Photochem Photobioljournal_title
Photochemistry and photobiologyauthors
Yu H,Wolford ST,Kegode R,Zhao W,Osweller GDdoi
10.1111/j.1751-1097.1996.tb02438.xsubject
Has Abstractpub_date
1996-07-01 00:00:00pages
168-73issue
1eissn
0031-8655issn
1751-1097journal_volume
64pub_type
杂志文章abstract：:Accurate determination of the diurnal variability and daily insolation of surface (0(+) ) and subsurface (0(-) ) irradiance are essential to estimate several physical, chemical and biological processes occurring at the surface layer of marine environments. Natural downwelling PAR and spectral UVR were examined on eigh...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/php.12474
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journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：
更新日期：1992-05-01 00:00:00
abstract：:Exposure to ultraviolet radiation is closely linked to the development of skin cancers in humans. The ultraviolet B (UVB) radiation wavelength (280-320 nm), in particular, causes DNA damage in epidermal keratinocytes, which are linked to the generation of signature premalignant mutations. Interactions between dermal f...
journal_title：Photochemistry and photobiology
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journal_title：Photochemistry and photobiology
pub_type： 杂志文章
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journal_title：Photochemistry and photobiology
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pub_type： 杂志文章
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journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1995.tb02382.x
更新日期：1995-09-01 00:00:00
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journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1993.tb04974.x
更新日期：1993-12-01 00:00:00
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journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1991.tb03638.x
更新日期：1991-03-01 00:00:00
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journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1992.tb02171.x
更新日期：1992-09-01 00:00:00
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journal_title：Photochemistry and photobiology
pub_type： 信件
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更新日期：2019-11-01 00:00:00
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pub_type： 杂志文章
doi：10.1111/php.13335
更新日期：2020-09-23 00:00:00
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doi：10.1562/2003-12-10-ra.1
更新日期：2004-06-01 00:00:00
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pub_type： 杂志文章
doi：10.1111/j.1751-1097.2007.00289.x
更新日期：2008-03-01 00:00:00
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pub_type： 杂志文章,评审
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更新日期：2011-11-01 00:00:00
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pub_type： 杂志文章
doi：10.1562/0031-8655(2001)074<0512:aotebb>2.0.co;2
更新日期：2001-10-01 00:00:00
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doi：10.1111/j.1751-1097.1989.tb09204.x
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journal_title：Photochemistry and photobiology
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doi：10.1111/j.1751-1097.1993.tb09559.x
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更新日期：2010-05-01 00:00:00
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pub_type： 杂志文章
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更新日期：2010-03-01 00:00:00
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pub_type： 杂志文章
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更新日期：2008-07-01 00:00:00
abstract：:Activation of expression of the heme oxygenase (HO) gene appears to be involved in a cellular defense system in mammalian cells. We now demonstrate that while HO-1 mRNA levels are strongly inducible in dermal fibroblasts they are barely inducible in human epidermal keratinocytes following oxidative stress (UVA radiati...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1995.tb03973.x
更新日期：1995-03-01 00:00:00
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journal_title：Photochemistry and photobiology
pub_type： 杂志文章,评审
doi：10.1562/2006-02-28-IR-823
更新日期：2007-01-01 00:00:00
abstract：:Photodynamic therapy (PDT) with photosensitizer verteporfin is a clinically approved vascular disrupting modality that is currently in clinical trial for cancer treatment. In this study, we evaluated PDT in combination with either mTORC1 inhibitor rapamycin or mTORC1/C2 dual inhibitor AZD2014 for therapeutic enhanceme...
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pub_type： 杂志文章
doi：10.1111/php.13187
更新日期：2020-03-01 00:00:00
