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Russu E, Arbanasi EM, Chirila TV, Muresan AV. Therapeutic strategies based on non-ionizing radiation to prevent venous neointimal hyperplasia: the relevance for stenosed arteriovenous fistula, and the role of vascular compliance. Front Cardiovasc Med 2024; 11:1356671. [PMID: 38374996 PMCID: PMC10875031 DOI: 10.3389/fcvm.2024.1356671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 01/23/2024] [Indexed: 02/21/2024] Open
Abstract
We have reviewed the development and current status of therapies based on exposure to non-ionizing radiation (with a photon energy less than 10 eV) aimed at suppressing the venous neointimal hyperplasia, and consequentially at avoiding stenosis in arteriovenous grafts. Due to the drawbacks associated with the medical use of ionizing radiation, prominently the radiation-induced cardiovascular disease, the availability of procedures using non-ionizing radiation is becoming a noteworthy objective for the current research. Further, the focus of the review was the use of such procedures for improving the vascular access function and assuring the clinical success of arteriovenous fistulae in hemodialysis patients. Following a brief discussion of the physical principles underlying radiotherapy, the current methods based on non-ionizing radiation, either in use or under development, were described in detail. There are currently five such techniques, including photodynamic therapy (PDT), far-infrared therapy, photochemical tissue passivation (PTP), Alucent vascular scaffolding, and adventitial photocrosslinking. The last three are contingent on the mechanical stiffening achievable by the exogenous photochemical crosslinking of tissular collagen, a process that leads to the decrease of venous compliance. As there are conflicting opinions on the role of compliance mismatch between arterial and venous conduits in a graft, this aspect was also considered in our review.
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Affiliation(s)
- Eliza Russu
- Clinic of Vascular Surgery, Mures County Emergency Hospital, Targu Mures, Romania
- Department of Vascular Surgery, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
| | - Emil-Marian Arbanasi
- Clinic of Vascular Surgery, Mures County Emergency Hospital, Targu Mures, Romania
- Department of Vascular Surgery, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
- Doctoral School of Medicine and Pharmacy, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
- Centre for Advanced Medical and Pharmaceutical Research (CCAMF), George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
| | - Traian V. Chirila
- Centre for Advanced Medical and Pharmaceutical Research (CCAMF), George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
- Queensland Eye Institute, Woolloongabba, QLD, Australia
- Faculty of Medicine, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
- School of Chemistry and Physics, Queensland University of Technology, Brisbane, QLD, Australia
- Australian Institute of Bioengineering and Nanotechnology (AIBN), University of Queensland, St Lucia, QLD, Australia
| | - Adrian V. Muresan
- Clinic of Vascular Surgery, Mures County Emergency Hospital, Targu Mures, Romania
- Department of Vascular Surgery, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
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de Lima RG, Tedesco AC, da Silva RS, Lawrence MJ. Ultradeformable liposome loaded with zinc phthalocyanine and [Ru(NH.NHq)(tpy)NO] 3+ for photodynamic therapy by topical application. Photodiagnosis Photodyn Ther 2017; 19:184-193. [PMID: 28578126 DOI: 10.1016/j.pdpdt.2017.05.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/16/2017] [Accepted: 05/18/2017] [Indexed: 01/25/2023]
Abstract
Ultradeformable liposomes (UDLs) as a drug delivery system (DDS), prepared from the unsaturated phospholipid, dioleylphosphocholine (DOPC), and containing the non-ionic surfactant Tween 20 as edge activator, have been explored as topical vehicles for zinc phthalocyanine (ZnPc) and the nitrosyl ruthenium complex [Ru(NH.NHq)(tpy)NO]3+ (RuNO) as a photosensitizers for co-generation of 1O2 and NO as reactive species, respectively. However, in order to ensure that ZnPc was present in the UDLs in its monomeric form - essential for maximal ZnPc photophysical properties - it was necessary to replace 40wt% of the DOPC with the saturated phospholipid, dimyristoylphosphocholine (DMPC). The resultant ZnPc and complex [Ru(NH.NHq)(tpy)NO]3+ containing UDLs were stable for at least a month when stored at 4°C, six times more elastic/deformable than conventional liposome (c-Ls), i.e. liposome prepared using the same weight ratio of lipids but in the absence of Tween 20, and to significantly enhance the in vitro permeation of ZnPc across fresh pig ear skin. The UDLs DDS incorporating ZnPc and [Ru(NH.NHq)(tpy)NO]3+ were toxic (by the MTT assay) towards B16-F10 melanoma cells when irradiated with visible light at 670nm, the maximum absorption of ZnPc, and at a dose of 3.18J/cm2, but not when applied in the absence of light as expected. Based on these results it is proposed that the novel topical UDLs formulation developed is a suitable delivery vehicle for photodynamic therapy.
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Affiliation(s)
- Renata Galvão de Lima
- Faculty of Sciences Integrated of Pontal, Federal University of Uberlândia, Brazil; Pharmaceutical Science Division, King's College London, Waterloo Campus, SE1 9NH, London, UK
| | - Antonio Cláudio Tedesco
- Departament of Chemistry, Laboratory of Photobiology and Photomedicine, Center of Nanotechnology and Tissue Engineer, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Brazil
| | | | - Margaret Jayne Lawrence
- Pharmaceutical Science Division, King's College London, Waterloo Campus, SE1 9NH, London, UK.
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Moussaron A, Arnoux P, Vanderesse R, Sibille E, Chaimbault P, Frochot C. Lipophilic phthalocyanines for their potential interest in photodynamic therapy: synthesis and photo-physical properties. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.09.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Shen YC, Upadhya PC, Davies AG, Linfield EH. Light-induced Difference Terahertz Spectroscopy. J Biol Phys 2013; 29:135-9. [PMID: 23345829 DOI: 10.1023/a:1024432507126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Visible/near-infraredlaser-induced difference spectroscopy basedon a time-domain terahertz system has beendeveloped, and used to study copperpathancyonine. We find that the absorptionpeak of this molecule at 1.08 THz changessignificantly under 790 nm laserexcitation, suggesting that we haveobserved the first evidence of vibrationalmode changes in the THz range induced byvisible/near-infrared light.
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Affiliation(s)
- Y C Shen
- Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge, CB3 0HE UK
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Peng C, Li Y, Liang H, Cheng J, Li Q, Sun X, Li Z, Wang F, Guo Y, Tian Z, Yang L, Tian Y, Zhang Z, Cao W. Detection and photodynamic therapy of inflamed atherosclerotic plaques in the carotid artery of rabbits. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2010; 102:26-31. [PMID: 20875747 DOI: 10.1016/j.jphotobiol.2010.09.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2010] [Revised: 08/22/2010] [Accepted: 09/02/2010] [Indexed: 11/29/2022]
Abstract
Photodynamic therapy (PDT) has been applied in the treatment of artery restenosis following balloon injury. This study aimed to detect the accumulation of 5-aminolevulinic acid (ALA)-derived protoporphyrin IX (PpIX) in inflamed atherosclerotic plaque in rabbit model and evaluate the efficacy of PDT. The inflamed atherosclerotic plaque in the common carotid artery was produced by combination of balloon denudation injury and high cholesterol diet. After intravenous administration of ALA, the fluorescence of PpIX in plaque was detected. At the peak time, the correlation between the fluorescence intensity of PpIX and the macrophage infiltration extent in plaque was analyzed. Subsequently, PDT (635nm at 50J/cm(2)) on the atherosclerotic plaques (n=48) was performed and its effect was evaluated by histopathology and immunohistochemistry. The fluorescence intensity of PpIX in the plaque reached the peak 2h after injection and was 12 times stronger than that of adjacent normal vessel segment, and has a positive correlation with the macrophage content (r=0.794, P<0.001). Compared with the control group, the plaque area was reduced by 59% (P<0.001) at 4week after PDT, the plaque macrophage content decreased by 56% at 1week and 64% at 4week respectively, the smooth muscle cells (SMCs) was depleted by 24% at 1week (P<0.05) and collagen content increased by 44% at 4week (P<0.05). It should be pointed out that the SMC content increased by 18% after PDT at 4week compared with that at 1week (P<0.05). Our study demonstrated that the ALA-derived PpIX can be detected to reflect the macrophage content in the plaque. ALA mediated PDT could reduce macrophage content and inhibit plaque progression, indicating a promising approach to treat inflamed atherosclerotic plaques.
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Affiliation(s)
- Chenghai Peng
- Department of Cardiology, The Second Affiliated Hospital, Harbin Medical University, Harbin 150086, PR China
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Preparation, chemical modification and absorption properties of various phthalocyanines. RESEARCH ON CHEMICAL INTERMEDIATES 2009. [DOI: 10.1007/s11164-008-0003-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Vittar NBR, Prucca CG, Strassert C, Awruch J, Rivarola VA. Cellular inactivation and antitumor efficacy of a new zinc phthalocyanine with potential use in photodynamic therapy. Int J Biochem Cell Biol 2008; 40:2192-205. [DOI: 10.1016/j.biocel.2008.02.024] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2007] [Revised: 02/18/2008] [Accepted: 02/27/2008] [Indexed: 01/23/2023]
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Heckenkamp J, Mellander S, Fogelstrand P, Breuer S, Brunkwall J, Mattsson E. Photodynamic Therapy Reduces Intimal Hyperplasia in Prosthetic Vascular Bypass Grafts in a Pig Model. Eur J Vasc Endovasc Surg 2007; 34:333-9. [PMID: 17513141 DOI: 10.1016/j.ejvs.2007.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Accepted: 04/01/2007] [Indexed: 11/28/2022]
Abstract
BACKGROUND Bypass surgery has a failing frequency of 30% during the first year, mainly due to intimal hyperplasia (IH). This negative effect is most pronounced in artificial grafts. Photodynamic therapy (PDT) is a technique in which light activates photosensitizer dyes to produce free-radicals resulting in an eradication of cells in the vascular wall. The aim of this study was to determine the effectiveness of PDT to reduce IH in a preclinical porcine PTFE bypass model. MATERIAL AND METHODS Ten pigs were used. After a pilot PDT dosimetry study (n=3) PTFE grafts were bilaterally placed into the circulation as bypasses from the common to the external iliac arteries (n=7). The right sides served as controls (C). Before implantation of the left grafts, the arterial connecting sites of the left distal anastomoses were PDT-treated. The arteries were pressurized at 180 mmHg for 5 minutes with the photosensitizer Methylene Blue (330 microg/ml), and thereafter endoluminally irradiated with laser light (lambda = 660 nm, 100 mW/cm(2), 150 J/cm(2)). After 4 weeks the specimens were retrieved and formalin fixed. Cross sections through the midportions of the distal anastomoses and the grafts were used for histology, immunohistochemistry to identify inflammatory cells and morphometric evaluation (n=7). RESULTS No systemic side effects and no graft occlusions were noted. PDT-treated anastomoses showed reduced IH in the mid-portions of the anastomoses (Area of IH: microm(2)/microm graft: C: 6970+/-1536, PDT: 2734+/-2560; P<0.005) as well as in the grafts (C: 5391+/-4031, PDT: 777+/-1331; P<0.02). The number of inflammatory cells per microscopic field was increased after PDT (C: 24+/-16, PDT: 37+/-15; P<0.009). CONCLUSIONS Adjuvant PDT, performed in an endovascular fashion, was a safe method to reduce prosthetic graftstenosis in a preclinical setting. This study underscores the clinical potential of PDT to inhibit the development of clinical bypass graftstenosis.
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Affiliation(s)
- J Heckenkamp
- Division of Vascular Surgery, Department of Vascular and Visceral Surgery, University of Cologne, Cologne, Germany.
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Sulphonated phthalocyanines as effective oxidation photocatalysts for visible and UV light regions. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.molcata.2007.03.024] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Fabris C, Soncin M, Miotto G, Fantetti L, Chiti G, Dei D, Roncucci G, Jori G. Zn(II)-phthalocyanines as phototherapeutic agents for cutaneous diseases. Photosensitization of fibroblasts and keratinocytes. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2006; 83:48-54. [PMID: 16427302 DOI: 10.1016/j.jphotobiol.2005.12.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2005] [Accepted: 12/05/2005] [Indexed: 10/25/2022]
Abstract
Two tetrasubstituted (RLP024 and RLP040) and one monosubstituted (MRLP101) Zn-phthalocyanines were readily accumulated by three skin-derived cell lines (HT-1080 transformed human fibroblasts, 3T3 mouse embryo fibroblasts and HaCaT human keratinocytes) upon 1 h-incubation with 0.5-5 microM phthalocyanine concentrations. The affinity was markedly larger for the tetra- as compared with the mono-substituted phthalocyanine, even though smaller phthalocyanine amounts were generally recovered from keratinocytes. As a consequence, the two tetra-substituted phthalocyanines exhibited a higher phototoxicity against all the three cell lines. Typically, the cell survival decreased by at least 80% after 1 min irradiation with 600-700 nm light at a fluence-rate of 50 mW/cm2 in the presence of 5 microM phthalocyanine. Fluorescence microscopy and caspase-3 activation studies indicate that cell death of fibroblasts largely occurred by a random-necrotic process while the keratinocytes underwent cell death predominantly via apoptosis in spite of a very similar pattern of subcellular distribution of the phthalocyanines.
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Affiliation(s)
- Clara Fabris
- Molteni Farmaceutici, S.S. 67 Loc.Granatieri, 50018 Scandicci, Firenze, Italy
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Carvalho PDTCD, Marques APDC, Reis FAD, Belchior ACG, Silva IS, Habitante CA, Sussai DA. Photodynamic inactivation of in vitro bacterial cultures from pressure ulcers . Acta Cir Bras 2006; 21 Suppl 4:32-5. [PMID: 17293963 DOI: 10.1590/s0102-86502006001000008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
PURPOSE: To evaluate in vitro the antibacterial effect of diode laser light of wavelength 650 nm, in association with the photosensitive substance toluidine blue, on the bacteria in infected skin ulcers. METHODS: Samples were collected by means of swabs containing a medium for transporting infected material from skin ulcers. The material was inoculated into culturing medium containing azide blood agar for the growth of Gram-positive bacteria, and MacConkey agar for Gram-negative bacteria, and incubated for 48 hours. The results obtained from counting the colony-forming units were correlated and subjected to statistical analysis, adopting the significance level of p > or = 0.05. RESULTS: From analysis of variance (ANOVA), the result for the general mean was p = 0.0215. Using the t test with post-hoc test, the result for TBO vs. Control was p = 0.0186, and for TBO + Laser vs. Control it was p = 0.0039. CONCLUSION: There was a significant reduction in colony-forming units when the cultures were subjected to photodynamic therapy.
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Magaraggia M, Visonà A, Furlan A, Pagnan A, Miotto G, Tognon G, Jori G. Inactivation of vascular smooth muscle cells photosensitised by liposome-delivered Zn(II)-phthalocyanine. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2005; 82:53-8. [PMID: 16243532 DOI: 10.1016/j.jphotobiol.2005.08.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Revised: 08/01/2005] [Accepted: 08/06/2005] [Indexed: 11/18/2022]
Abstract
Photodynamic therapy is a promising approach for the prevention of arterial restenosis, which frequently occurs after balloon angioplasty, largely owing to abnormal proliferation of vascular smooth muscle cells (VSMC) and their migration from the media to the intima, where they originate intimal hyperplasia (IH). We investigated the efficacy of Zn(II)-phthalocyanine-photosensitised processes in promoting the inactivation of VSMC. This liposome delivered phthalocyanine is readily taken up by VSMC, largely partitions in the Golgi apparatus, and upon photoactivation causes >95% cell mortality using mild irradiation conditions (e.g. 5 min irradiation at 1 microM ZnPc). Cell death occurs through the parallel development of random necrotic and apoptotic processes.
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Affiliation(s)
- Michela Magaraggia
- Dipartimento di Biologia, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy.
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Fabris C, Soncin M, Mazzon E, Calzavara-Pinton P, Lia F, Giacomo C, Dei D, Tampucci S, Roncucci G, Jori G. A novel tetracationic phthalocyanine as a potential skin phototherapeutic agent. Exp Dermatol 2005; 14:675-83. [PMID: 16098127 DOI: 10.1111/j.0906-6705.2005.00339.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
An amphiphilic tetracationic derivative of Zn(II)-phthalocyanine (RLP068) was prepared by means of chemical synthesis and was showed to possess efficient photophysical and photosensitizing properties against model biological substrates. RLP068 was incorporated into a gel formulation, which allowed its ready penetration into the epidermal layers, but not into the dermis, of both Balb/c and hairless SKH1 mice after 1-2 h of topical deposition. Pharmacokinetic studies showed that the phthalocyanine thus formulated does not enter the general blood circulation. The epidermis-associated amount of phthalocyanine was sufficient to cause an important cutaneous damage upon irradiation with red light (600-700 nm; 100-180 mW/cm(2), 160 J/cm(2)); the latter was confined to the epidermal area with no apparent diffusion to the underlying dermal layers or appearance of photosensitivity in distal skin areas. A systematic investigation of the interplay among the different parameters (deposition time of the formulated phthalocyanine on mouse skin, irradiation fluence rate and total light fluence) allowed us to identify the minimal phototoxic dose, as well as to define irradiation protocols allowing the repeatability of the phototherapeutic treatment. The potential of RLP068 to act as a PDT agent for cutaneous diseases is briefly discussed.
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Kaestner L, Cesson M, Kassab K, Christensen T, Edminson PD, Cook MJ, Chambrier I, Jori G. Zinc octa-n-alkyl phthalocyanines in photodynamic therapy: photophysical properties, accumulation and apoptosis in cell cultures, studies in erythrocytes and topical application to Balb/c mice skin. Photochem Photobiol Sci 2003; 2:660-7. [PMID: 12859150 DOI: 10.1039/b211348a] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two octa-substituted phthalocyanines, namely 1,4,8,11,15,18,22,25-octakis(decyl)phthalocyaninato zinc(II) (ZnODPc) and 1,4,8,11,15,18,22,25-octakis(pentyl)phthalocyaninato zinc(II) (ZnOPPc), were investigated for their use in photodynamic therapy (PDT) after topical application. Both substances exhibited favourable properties as photosensitisers in vitro: absorption maxima around 700 nm with absorption coefficients of about 190000 (M(-1) cm(-1)), a singlet oxygen quantum yield of 0.47 +/- 0.02 (ZnODPc), and good accumulation in keratinocytes and fibroblasts. Cell death after phthalocyanine-photosensitisation appeared to occur mainly via apoptosis. The in vivo experiments demonstrated a good accumulation of the phthalocyanines after topical application in a tetrahydrofuran-azone formulation onto the dorsal skin of Balb/c mice: [(4.6-4.7) +/- 1.0]% of deposited dye could be recovered after 3 h from deposition. ZnODPc showed significantly better skin-photosensitising properties than ZnOPPc and is therefore a potential candidate for the treatment of psoriasis.
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Affiliation(s)
- R Mansfield
- Cardiovascular Repair and Remodelling Group, The Hatter Institute, Royal Free and UCL Medical School, Middlesex Hospital, Mortimer Street, London W1N 8AA, UK.
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Fabris C, Jori G, Giuntini F, Roncucci G. Photosensitizing properties of a boronated phthalocyanine: studies at the molecular and cellular level. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2001; 64:1-7. [PMID: 11705724 DOI: 10.1016/s1011-1344(01)00184-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A synthetic procedure has been developed for the preparation of a Zn-phthalocyanine peripherally substituted with a dodecaborane. The absorption spectrum of the derivative is typical of the phthalocyanine chromophore. Moreover, the boronated phthalocyanine exhibits a high photosensitizing efficiency against a model biological substrate, such as N-acetyl-L-tryptophanamide, and a singlet oxygen quantum yield of 0.53 in dimethylformamide. Even though the presence of the dodecaborane moiety appears to decrease the affinity of the phthalocyanine for HT-1080 transformed human fibroblasts, the boronated phthalocyanine causes an essentially complete loss of cell viability upon irradiation with 600-700 nm light under mild conditions (1 microM concentration, 5-min irradiation at 10 mW/cm(2)).
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Affiliation(s)
- C Fabris
- Molteni Farmaceutici, S.S 67 Loc. Granatieri - 50018 Scandicci, Florence, Italy.
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