Hypocrellin A photosensitization involves an intracellular pH decrease in 3T3 cells.
AuthorsChaloupka R, Sureau F, Kocisova E, Petrich JW
JournalPhotochem Photobiol
PubMed ID9679450
'The fluorescent pH probe carboxy-seminaphtorhodafluor-1 (C-Snarf-1) has been used for laser microspectro-fluorometric assays of intracellular pH in 3T3 mouse fibroblasts treated with hypocrellin A. These results are compared to those previously obtained with the structurally related hydroxylated polycyclic quinone, hypericin (Sureau et al., J. Am. Chem. Soc. 118, 9484-9487, 1996). ... More
Phototherapeutic potential of alternative photosensitizers to porphyrins.
AuthorsDiwu Z, Lown JW
JournalPharmacol Ther
PubMed ID7972342
'Because of promising clinical results obtained with photodynamic therapy, more and more photosensitizers continue to be isolated (from natural sources), synthesized and evaluated, the development of which is considered to be a key factor for the successful clinical application of photodynamic therapy. Porphyrins and their analogs (as classical types of ... More
Novel therapeutic and diagnostic applications of hypocrellins and hypericins.
AuthorsDiwu Z
JournalPhotochem Photobiol
PubMed ID7568399
'Hypocrellins and hypericins, structurally related plant pigments isolated from Hypocrella bambuase and Hypericum respectively, are known photodynamic agents. This review summarizes certain significant advances in the photophysics, photochemistry and photobiology of these pigments in the last 2 years and discusses their prospects as novel therapeutic and diagnostic agents in the ... More
Roles of oxygen and photoinduced acidification in the light-dependent antiviral activity of hypocrellin A.
AuthorsFehr MJ, Carpenter SL, Wannemuehler Y, Petrich JW
JournalBiochemistry
PubMed ID7495816
'Hypocrellin A displays photoinduced antiviral activity, in particular against the human immunodeficiency virus (HIV), as does its counterpart, hypericin. Although hypocrellin A, like hypericin, executes an excited-state intramolecular proton transfer, it differs from hypericin in two important ways. Unlike hypericin, hypocrellin A absolutely requires oxygen for its antiviral activity. Also, ... More
DNA damage induced by hypocrellin-A photosensitization.
AuthorsCao EH, Xin SM, Cheng LS
JournalInt J Radiat Biol
PubMed ID1351909
'Hypocrellin-A (HC-A) isolated from Hypocrellia bambusae Sacc., is a new and effective photosensitizer. Illumination of sarcoma 180 cells with visible light in the presence of HC-A leads to a decrease in cell viability and 3H-TdR incorporation, causes DNA strand breakage, and results in the selective destruction of guanine moieties in ... More
New potential photodynamic therapeutic anti-cancer agents: synthesis and characterization of demethoxy amino-substituted hypocrellins.
AuthorsWu T, Xu S, Shen J, Song A, Chen S, Zhang M, Shen T
JournalAnticancer Drug Des
PubMed ID11200504
'A novel method was used to obtain demethoxy amino-substituted hypocrellin derivatives. The reaction condition was mild and amino substitution occurred at position 2 or 11 of hypocrellins with high yield. The photophysical and photochemical properties of the amino-substituted hypocrellins derivatives were investigated, and their significantly enhanced red absorptivities and strong ... More
Photoinactivation of virus infectivity by hypocrellin A.
AuthorsHirayama J, Ikebuchi K, Abe H, Kwon KW, Ohnishi Y, Horiuchi M, Shinagawa M, Ikuta K, Kamo N, Sekiguchi S
JournalPhotochem Photobiol
PubMed ID9383993
'We investigated the photoinactivation of virus infectivity by hypocrellin A and its mechanism. The titers of vesicular stomatitis virus (VSV) and human immunodeficiency virus type 1 (HIV-1), both of which are enveloped viruses, were reduced upon illumination with hypocrellin A in a concentration-dependent manner, whereas canine parvovirus, a nonenveloped virus, ... More
Research at the Interface between Chemistry and Virology: Development of a Molecular Flashlight.
AuthorsKraus GA, Zhang W, Fehr MJ, Petrich JW, Wannemuehler Y, Carpenter S
JournalChem Rev
PubMed ID11848763
Hypocrellin, from Hypocrella bambuase, is phototoxic to human immunodeficiency virus.
Hypocrellin, a photodynamic perylene quinonoid isolated from the Chinese medicinal fungus Hypocrella bambuase, was evaluated for antiviral activity against the human immunodeficiency virus (HIV-1). Hypocrellin was phototoxic to HIV-1, almost as good as the structurally similar plant pigment hypericin, and like hypericin its activity required visible light. In contrast peroxyhypocrellin ... More
Multidimensional reaction coordinate for the excited-state H-atom transfer in perylene quinones: importance of the 7-membered ring in hypocrellins A and B.
AuthorsDatta A, Smirnov AV, Wen J, Chumanov G, Petrich JW
JournalPhotochem Photobiol
PubMed ID10687390
The excited-state intramolecular H-atom transfer reactions of hypocrellins B and A are compared by using time-resolved absorption and fluorescence upconversion techniques. The hypocrellin B photophysics are well described by a simple model involving one ground-state species and excited-state forward and reverse H-atom transfer with a nonfluorescent excited state. We suggest ... More
EPR-spin trapping kinetic studies of superoxide radicals produced by photosensitized hypocrellin A. A photodynamic therapeutic agent.
AuthorsZang LY, Shi X, Misra HP
JournalBiochem Mol Biol Int
PubMed ID8728097
Kinetics of superoxide radicals generation by a photodynamic therapeutic agent, Hypocrellin A has been studied by EPR-spin trapping technique. The rate constant (k(g)) for superoxide radicals generation by Hypocrellin A was found to be 5.0 x 10(-3) s-1. The first-order rate constant (k1) and the half-life time (t0.5) for DMPO-O2- ... More
The role of oxygen in the antiviral activity of hypericin and hypocrellin.
AuthorsPark J, English DS, Wannemuehler Y, Carpenter S, Petrich JW
JournalPhotochem Photobiol
PubMed ID9796444
The light-induced antiviral activity of hypericin and hypocrellin in the presence and absence of oxygen was examined under experimental conditions where the effect of oxygen depletion could be quantified. There was a significant reduction of light-induced antiviral activity of hypericin and hypocrellin under hypoxic conditions. Interestingly, antiviral activity of hypocrellin ... More
Photosensitization with anticancer agents. 18. Perylenequinonoid pigments as potential photodynamic therapeutic agents: preparation and photodynamic properties of amino-substituted hypocrellin derivatives.
AuthorsDiwu Z, Zhang C, Lown JW
JournalAnticancer Drug Des
PubMed ID8494603
Perylenequinonoid pigments have demonstrated several photodynamic therapeutic advantages over the commonly used hematoporphyrin derivatives. Certain new amino-substituted hypocrellin B derivatives have been prepared, and both direct and reductive aminations of hypocrellin B are described. The photophysical and photochemical properties of the amino-substituted hypocrellin B derivatives were investigated, and their significantly ... More
Laser-induced fluorescence detection of cardiovascular atherosclerotic deposits via their natural emission and hypocrellin (HA) probing.
AuthorsPapazoglou TG, Liu WQ, Katsamouris A, Fotakis C
JournalJ Photochem Photobiol B
PubMed ID8176547
In order to develop a reliable laser-induced-fluorescence-guided angioplasty system, fluorescence spectra were recorded during exposure of normal and atherosclerotic cadaveric aortic tissue to He-Cd laser radiation (442 nm). A characteristic increase in the fluorescence signal at 600 nm for atheromatous tissue was observed after treatment of the samples with hypocrellin ... More
Hypocrellins and their use in photosensitization.
AuthorsZhenjun D, Lown JW
JournalPhotochem Photobiol
PubMed ID2284353
Hypocrellins A and B are pigments which are isolated from parasitic fungi Hypocrella bambuase (B. et Br) sacc. and Shiraia bambusicola P. Heen found in the People's Republic of China (P.R.C.) and Sri Lanka respectively. These agents, which belong to the general class of perylene quinonoid pigments, have a long ... More
Application of a novel fluorescence probe in the determination of nucleic acids.
AuthorsZhu QZ, Li F, Guo XQ, Xu JG, Li WY
JournalAnalyst
PubMed ID9374024
A novel fluorimetric method has been developed for rapid determination of DNA and RNA with hypocrellin A (HA) as a fluorescence probe, based on the fluorescence enhancement of HA in the presence of DNA or RNA. Maximum fluorescence is produced in the pH range 3.4-4.0, with maximum excitation and emission ... More
Interaction of antiviral and antitumor photoactive drug hypocrellin A with human serum albumin.
Absorption, resonance Raman, surface-enhanced Raman spectroscopy and differential scanning microcalorimetry were employed to study the interaction of hypocrellin A with human serum albumin. The identification of the binding place for hypocrellin A as well as the model for the albumin-hypocrellin A complex are proposed. In this model hypocrellin A interacts ... More
Antiviral activities of photoactive perylenequinones.
AuthorsHudson JB, Imperial V, Haugland RP, Diwu Z
JournalPhotochem Photobiol
PubMed ID9066311
Nine perylenequinones (PQ), including some familiar naturally occurring pigments, were compared for their light-mediated antiviral efficacies. Calphostin C was the most active compound against the two target viruses, herpes simplex virus type 1 and Sindbis virus. Hypocrellins A and B were also very active. However, three cercosporin-like PQ were substantially ... More
Laser-induced fluorescence detection of malignancies in the female genital tract via their natural emission and hypocrellin (HA) probing.
AuthorsKoumantakis E, Liu WQ, Makrigiannakis A, Relakis C, Unsöld E, Papazoglou TG
JournalJ Photochem Photobiol B
PubMed ID9043098
A laser-induced fluorescence-guided biopsy system has been developed for the screening and early detection of malignancies in the female inner/outer genital tract. Fluorescence spectra were recorded during exposure of normal and malignant tissue to He-Cd laser (442 nm) radiation. A characteristic increase in the fluorescence signal at 600 nm for ... More
Studies on the chelation of hypocrellin A with aluminium ion and the photodynamic action of the resulting complex.
AuthorsHu YZ, An JY, Jiang LJ
JournalJ Photochem Photobiol B
PubMed ID8014754
Hypocrellin A (HA), a perylenoquinone derivative, is an efficient phototherapeutic agent. The chelation of HA with aluminium ion (Al3+) results in the formation of a 1:1 complex (Al(3+)-HA). The probable structure for this complex has been proposed. Compared with HA, this complex has a much higher solubility in water. In ... More
Photodynamic action of amino substituted hypocrellins: EPR studies on the photogenerations of active oxygen and free radical species.
AuthorsWu T, Shen J, Song A, Chen S, Zhang M, Shen T
JournalJ Photochem Photobiol B
PubMed ID11100833
A novel method has been employed to prepare 2-butylamino-2-demethoxy hypocrellin A (BADMHA) and 2-butylamino-2-demethoxy hypocrellin B (BADMHB). Both compounds exhibit stronger absorption at the phototherapeutic window (600-900 nm). The spin trapping and spin counteraction studies have shown that they are both efficient generators of the active oxygen (1O2, O2*-) in ... More
Photodynamic effects of hypocrellin A on three human malignant cell lines by inducing apoptotic cell death.
AuthorsZhang J, Cao EH, Li JF, Zhang TC, Ma WJ
JournalJ Photochem Photobiol B
PubMed ID9679312
Hypocrellin A (HA), a lipid-soluble peryloquinone derivative extracted from the fungus Hypocrella bambusae, has been proved to be effective in treating many diseases. In this study, we have examined the photodynamic effects of HA on three different human malignant epithelioid cell lines, i.e., HIC, MGC-803 and HeLa cells. They all ... More
[An experimental study on photosensitization of cultured human cells with hypocrellin A]
AuthorsWang JZ, Li JF, Zhang XZ
JournalShi Yan Sheng Wu Xue Bao
PubMed ID7976055
The photosensitive effects of hypocrellin A on cultured HeLa cells were studied by the methods of immunofluorescence cytochemistry, flow cytometry and others. The results showed that, in the presence of 3.66 mumol/L hypocrellin A, illumination of HeLa cells with visible light, the morphology was changed and the microvilli on the ... More
A novel photosensitizer, 2-butylamino-2-demethoxy-hypocrellin A (2-BA-2-DMHA). 1. Synthesis of 2-BA-2-DMHA and its phototoxicity to MGC803 cells.
AuthorsZhang WG, Weng M, Pang SZ, Zhang MH, Yang HY, Zhao HX, Zhang ZY
JournalJ Photochem Photobiol B
PubMed ID9745725
The reaction of hypocrellin A (HA) with n-butylamine in pyridine under reflux leads to the formation of 2-butylamino-2-demethoxy-hypocrellin A (2-BA-2-DMHA), which is illustrated by ultraviolet-visible absorption spectra, proton nuclear magnetic resonance spectra, infrared spectra and mass spectra. The product exhibits stronger red-light absorption and has a much higher photopotentiation factor ... More
Photosensitization with anticancer agents. 16. The photo-oxidation of hypocrellin A. A mechanism study using 18O labelling.
AuthorsDiwu Z, Lown JW
JournalJ Photochem Photobiol B
PubMed ID8350181
Hypocrellin A was selected as a representative structure to investigate the mechanism of photo-oxidation of perylenequinonoid pigments (PQPs). It was found that singlet oxygen plays a key role in the photo-oxidation of PQPs. The following processes were determined to be involved in the photo-oxidation of PQPs using 18O atom labelling. ... More
Hypocrellins as photosensitizers for photodynamic therapy: a screening evaluation and pharmacokinetic study.
AuthorsEstey EP, Brown K, Diwu Z, Liu J, Lown JW, Miller GG, Moore RB, Tulip J, McPhee MS
JournalCancer Chemother Pharmacol
PubMed ID8548880
Hypocrellin compounds were selected as potential photosensitizers for photodynamic therapy (PDT) owing to their high quantum yields of singlet oxygen (1O2), and facility for site-directed chemical modification to enhance phototoxicity, pharmacokinetics, solubility, and light absorption in the red spectral region, among other properties. Parent hypocrellins A and B share an ... More
Photosensitization with anticancer agents. 15. Perylenequinonoid pigments as potential photodynamic therapeutic agents: formation of semiquinone radicals and reactive oxygen species on illumination.
AuthorsDiwu Z, Lown JW
JournalJ Photochem Photobiol B
PubMed ID8394416
Visible light illumination of solutions of perylenequinonoid pigments generates the corresponding semiquinone radicals, singlet oxygen, superoxide anion radical, hydroxyl radical and hydrogen peroxide. In anaerobic solution, the semiquinone radicals are predominantly photoproduced via the self-electron transfer between the excited and ground state species. In aerobic solution, singlet oxygen is the ... More
Hypocrellin and hypericin-induced phototoxicity of HL-60 cells: apoptosis or necrosis?
AuthorsMirossay A, Mojzis J, Tóthová J, Hájiková M, Lacková A, Mirossay L
JournalPhytomedicine
PubMed ID11194175
Hypericin and hypocrellin are potential antiviral and antineoplastic agents with multiple modes of light-induced biological activity connected with a production of singlet oxygen and/or excited-state proton transfer and consequent pH drop formation in the drugs environment. In present work light-induced cytotoxicity of hypericin and hypocrellin and mechansim of cell death ... More
Design, synthesis and investigation of mechanisms of action of novel protein kinase C inhibitors: perylenequinonoid pigments.
AuthorsDiwu Z, Zimmermann J, Meyer T, Lown JW
JournalBiochem Pharmacol
PubMed ID7508231
A series of perylenequinonoid pigments (PQPs) and related compounds were synthesized and screened for the inhibition of protein kinase C (PKC), a key enzyme involved in cellular differentiation and proliferation, and a potential target for anticancer and antiviral chemotherapeutic drugs. This study has established PQPs as efficient PKC inhibitors, and ... More
Pharmacokinetics, tissue distribution and photodynamic therapy efficacy of liposomal-delivered hypocrellin A, a potential photosensitizer for tumor therapy.
AuthorsWang ZJ, He YY, Huang CG, Huang JS, Huang YC, An JY, Gu Y, Jiang LJ
JournalPhotochem Photobiol
PubMed ID10568169
Hypocrellin A, from Hypocrella bambusae, is a novel photosensitizer of high singlet oxygen quantum yield for photodynamic therapy (PDT). Tissue distributions were studied in tumor-bearing mice as a function of time following administration. The tumor model was S-180 sarcoma transplanted into one hind leg of male Kunming mice; hypocrellin A ... More
Generation of free radicals during photosensitization of hypocrellin A and their effects on cardiac membranes.
AuthorsZang LY, Misra BR, Misra HP
JournalPhotochem Photobiol
PubMed ID1454876
Hypocrellin A (HA), a peryloquinone derivative, has recently been isolated from a fungus Hypocrella bambusae. This lipid soluble pigment, in combination with phototherapy, has been used to treat many skin diseases including the keloids caused by scalding and burns. We have studied the effects of photosensitized HA on biomembranes using ... More