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Cao Y, Zhang X, Ren B, Yang X. Lactose-conjugated porphyrin: synthesis and photobiological evaluation as potential agents for photodynamic therapy. CAN J CHEM 2021. [DOI: 10.1139/cjc-2021-0030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Porphyrin-based photosensitizers are conventional photodynamic agents that are used clinically. However, their clinical applications have been overshadowed by poor water solubility. In addition, they have weak tumor selectivity, which may cause undesirable side effects. The preparation of novel porphyrin derivatives has been explored for potential applications in photodynamic therapy (PDT). To achieve this goal, lactose-conjugated porphyrin nanoparticles (Lac-Por NPs) have been synthesized and characterized. PDT with Lac-Por NPs exhibited tumor-specific cytotoxicity in lactose receptor-overexpressing HepG2 cells in vitro and in vivo. In summary, we designed and synthesized lactose conjugate porphyrins with enhanced water solubility and tumor selectivity. This work expands the application range of porphyrin-based photosensitizers for cancer treatment.
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Affiliation(s)
- Yue Cao
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, Jilin 130052, People’s Republic of China
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, Jilin 130052, People’s Republic of China
| | - Xin Zhang
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, Jilin 130052, People’s Republic of China
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, Jilin 130052, People’s Republic of China
| | - Bo Ren
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, Jilin 130052, People’s Republic of China
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, Jilin 130052, People’s Republic of China
| | - Xiaodong Yang
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, Jilin 130052, People’s Republic of China
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, Jilin 130052, People’s Republic of China
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Lin Y, Zhou T, Bai R, Xie Y. Chemical approaches for the enhancement of porphyrin skeleton-based photodynamic therapy. J Enzyme Inhib Med Chem 2020; 35:1080-1099. [PMID: 32329382 PMCID: PMC7241559 DOI: 10.1080/14756366.2020.1755669] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 04/06/2020] [Accepted: 04/09/2020] [Indexed: 01/15/2023] Open
Abstract
With the development of photodynamic therapy (PDT), remarkable studies have been conducted to generate photosensitisers (PSs), especially porphyrin PSs. A variety of chemical modifications of the porphyrin skeleton have been introduced to improve cellular delivery, stability, and selectivity for cancerous tissues. This review aims to highlight the developments in porphyrin-based structural modifications, with a specific emphasis on the role of PDT in anticancer treatment and the design of PSs to achieve a synergistic effect on multiple targets.
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Affiliation(s)
- Yuyan Lin
- Collaborative Innovation Centre of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, China
| | - Tao Zhou
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Renren Bai
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, China
| | - Yuanyuan Xie
- Collaborative Innovation Centre of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, China
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, China
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Singh S, Aggarwal A, Bhupathiraju NVSDK, Arianna G, Tiwari K, Drain CM. Glycosylated Porphyrins, Phthalocyanines, and Other Porphyrinoids for Diagnostics and Therapeutics. Chem Rev 2015; 115:10261-306. [PMID: 26317756 PMCID: PMC6011754 DOI: 10.1021/acs.chemrev.5b00244] [Citation(s) in RCA: 358] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Sunaina Singh
- Department of Natural Sciences, LaGuardia Community College of the City University of New York, Long Island City, New York 11101, United States
| | - Amit Aggarwal
- Department of Natural Sciences, LaGuardia Community College of the City University of New York, Long Island City, New York 11101, United States
| | - N. V. S. Dinesh K. Bhupathiraju
- Department of Chemistry and Biochemistry, Hunter College of the City University of New York, New York, New York 10065, United States
| | - Gianluca Arianna
- Department of Chemistry and Biochemistry, Hunter College of the City University of New York, New York, New York 10065, United States
| | - Kirran Tiwari
- Department of Chemistry and Biochemistry, Hunter College of the City University of New York, New York, New York 10065, United States
| | - Charles Michael Drain
- Department of Chemistry and Biochemistry, Hunter College of the City University of New York, New York, New York 10065, United States
- The Rockefeller University, New York, New York 10065, United States
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Moylan C, Sweed AM, Shaker YM, Scanlan EM, Senge MO. Lead structures for applications in photodynamic therapy 7. Efficient synthesis of amphiphilic glycosylated lipid porphyrin derivatives: refining linker conjugation for potential PDT applications. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.04.097] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Titov DV, Gening ML, Tsvetkov YE, Nifantiev NE. Glycoconjugates of porphyrins with carbohydrates: methods of synthesis and biological activity. RUSSIAN CHEMICAL REVIEWS 2014. [DOI: 10.1070/rc2014v083n06abeh004426] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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6
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Chauvin B, Iorga BI, Chaminade P, Paul JL, Maillard P, Prognon P, Kasselouri A. Plasma distribution of tetraphenylporphyrin derivatives relevant for Photodynamic Therapy: Importance and limits of hydrophobicity. Eur J Pharm Biopharm 2013; 83:244-52. [DOI: 10.1016/j.ejpb.2012.09.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 09/06/2012] [Accepted: 09/21/2012] [Indexed: 11/16/2022]
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Mikata Y, Shibata M, Baba Y, Kakuchi T, Nakai M, Yano S. Synthesis and photodynamic properties of maltohexaose-conjugated porphyrins. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s1088424612501155] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A series of porphyrin derivatives with one to four maltohexaose moieties in their meso positions have been synthesized. Zinc or free-base m-THPP (5,10,15,20-tetrakis(m-hydroxyphenyl)-porphyrin) was used as the porphyrin platform. The reaction of m-THPP with 3-iodopropyl nonadecaacetylmaltohexaoside afforded a mixture of all possible combinations of glycoconjugated porphyrins having one to four maltohexaose moieties; monoglycosylated (Ac-1), bisglycosylated (Ac-cis-2 and Ac-trans-2), triglycosylated (Ac-3), and tetraglycosylated (Ac-4) porphyrins were obtained in 11–26% yield. Removal of acetyl groups at maltohexaose moiety afforded highly water-soluble glycoconjugated porphyrins 1–4. Zinc derivatives were synthesized in a similar manner. These maltohexaose-linked porphyrins exhibit remarkable water-solublity (530 mg/mL for 4). The singlet oxygen production ability upon visible light irradiation is not affected by the maltohexaose substitution. Photo- and dark cytotoxicities of the maltohexaose-conjugated porphyrins 1–4 and Zn-1–4 were examined against a HeLa cell line, which showed that the mono-maltohexaosylated derivative (1 and Zn-1) was the most effective photosensitizer for PDT.
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Affiliation(s)
- Yuji Mikata
- KYOUSEI Science Center, Nara Women's University, Nara 630-8506, Japan
| | - Minako Shibata
- Graduate School of Engineering, Division of Biotechnology and Macromolecular Chemistry, Hokkaido University, Sapporo 060-8628, Japan
| | - Yasuko Baba
- Graduate School of Engineering, Division of Biotechnology and Macromolecular Chemistry, Hokkaido University, Sapporo 060-8628, Japan
| | - Toyoji Kakuchi
- Graduate School of Engineering, Division of Biotechnology and Macromolecular Chemistry, Hokkaido University, Sapporo 060-8628, Japan
| | - Misaki Nakai
- Materials and Bioengineering, Kansai University, Osaka 564-8680, Japan
| | - Shigenobu Yano
- Graduate School of Material Science, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma, Nara 630-0192, Japan
- Office of Society-Academia Collaboration for Innovation, Kyoto University, Kyoto University Katsura, Nishikyo-ku, Kyoto-daigaku Katsura, Kyoto 615-8520, Japan
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Wang ZJ, Chauvin B, Maillard P, Hammerer F, Carez D, Croisy A, Sandré C, Chollet-Martin S, Prognon P, Paul JL, Blais J, Kasselouri A. Glycodendrimeric phenylporphyrins as new candidates for retinoblastoma PDT: Blood carriers and photodynamic activity in cells. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2012; 115:16-24. [DOI: 10.1016/j.jphotobiol.2012.06.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 05/30/2012] [Accepted: 06/11/2012] [Indexed: 11/26/2022]
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Ballut S, Makky A, Chauvin B, Michel JP, Kasselouri A, Maillard P, Rosilio V. Tumor targeting in photodynamic therapy. From glycoconjugated photosensitizers to glycodendrimeric one. Concept, design and properties. Org Biomol Chem 2012; 10:4485-95. [PMID: 22569817 DOI: 10.1039/c2ob25181g] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In this paper, we discuss the evolution over the last 15 years in the Curie Institute of the concept, the development of the design and some properties of glycoconjugated photosensitizers with the aim to optimize the tumor targeting in photodynamic therapy. By this research, we have shown that specific interactions between a mannose-lectin and trimannosylglycodendrimeric porphyrins contributed to a larger extent than non-specific ones to the overall interaction of a glycosylated tetraarylporphyrin with a membrane. The studies of in vitro photocytotoxicity showed the relevance of the global geometry of the photosensitizer, the number and position of the linked glycopyranosyl groups on the chromophore and their lipophilicity. The two best compounds appeared to be porphyrins bearing three α-glycosyl groups on para-position of meso-phenyl via a flexible linker. Compound bearing α-manosyl moieties was evaluated successfully in two in vivo xenografted animal models of human retinoblastoma and colorectal cancers. Conversely, the presence on the chromophore of three sugars via a glycodendrimeric moiety induced a potential cluster effect, but decreased the in vitro photoefficiency despite a good affinity for a mannose-lectin.
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Affiliation(s)
- Séverine Ballut
- Institut Curie, Centre de Recherche, Bât 110-112, Orsay, F-91405, France
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Senge MO. mTHPC--a drug on its way from second to third generation photosensitizer? Photodiagnosis Photodyn Ther 2011; 9:170-9. [PMID: 22594988 DOI: 10.1016/j.pdpdt.2011.10.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 10/07/2011] [Indexed: 10/15/2022]
Abstract
5,10,15,20-Tetrakis(3-hydroxyphenyl)chlorin (mTHPC, Temoporfin) is a widely investigated second generation photosensitizer. Its initial use in solution form (Foscan®) is now complemented by nanoformulations (Fospeg®, Foslip®) and new chemical derivatives related to the basic hydroxyphenylporphyrin framework. Advances in formulation, chemical modifications and targeting strategies open the way for third generation photosensitizers and give an illustrative example for the developmental process of new photoactive drugs.
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Affiliation(s)
- Mathias O Senge
- Medicinal Chemistry, Institute of Molecular Medicine, Trinity Centre for Health Sciences, Trinity College Dublin, St James's Hospital, Dublin 8, Ireland.
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Achelle S, Couleaud P, Baldeck P, Teulade-Fichou MP, Maillard P. Carbohydrate-Porphyrin Conjugates with Two-Photon Absorption Properties as Potential Photosensitizing Agents for Photodynamic Therapy. European J Org Chem 2011. [DOI: 10.1002/ejoc.201001209] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Maillard P, Lupu M, Thomas CD, Mispelter J. [Towards a new treatment of retinoblastoma?]. ANNALES PHARMACEUTIQUES FRANÇAISES 2010; 68:195-202. [PMID: 20569775 DOI: 10.1016/j.pharma.2010.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Revised: 02/24/2010] [Accepted: 03/04/2010] [Indexed: 01/10/2023]
Abstract
Photodynamic therapy (PDT) is a recent approach for the treatment of small cancerous tumours, on-surface or accessible by endoscopy in which a dye (usually a tetrapyrrolic macrocycle) absorbs light and generates cytotoxic reactive oxygen species leading to cellular damage. Retinoblastoma (Rb) is a rare intraocular tumour of childhood. All the multifocal forms are hereditary and constitute a syndrome of genetic predisposition in the cancer. The current treatments with etoposide or carboplatine expose the patient to the late risk of second cancer. The use of PDT as cancer therapy is particularly attractive due to the use of few mutagenic and non-toxic photosensitizers (PS) prior light excitation and to the localized tumour illumination. The photoefficiency towards Rb of a glycoconjugated porphyrin is discussed and compared with the results obtained with a second-generation photosensitizer, the Foscan. Some in vivo results on an animal model of Rb are presented by a point of view of photoefficiency, biodistribution, pharmacokinetic and longitudinal follow-up of the PDT effect using a new non-invasive method of magnetic resonance imaging of real-time. Photodynamic treatments in association with non-invasive sodium imaging open ways for new treatment tailoring or treatment individualization of retinoblastoma in clinic.
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Affiliation(s)
- P Maillard
- UMR 176 CNRS, institut Curie, bâtiments 110-112, centre universitaire, université Paris-Sud, 91405 Orsay, France.
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Zhou C, Gan L, Zhang Y, Zhang F, Wang G, Jin L, Geng R. Review on supermolecules as chemical drugs. SCIENCE IN CHINA. SERIES B, CHEMISTRY 2009; 52:415-458. [PMID: 38624300 PMCID: PMC7089408 DOI: 10.1007/s11426-009-0103-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Accepted: 12/28/2008] [Indexed: 11/01/2022]
Abstract
Supramolecular medicinal chemistry field has been a quite rapidly developing, increasingly active and newly rising interdiscipline which is the new expansion of supramolecular chemistry in pharmaceutical sciences, and is gradually becoming a relatively independent scientific area. Supramolecular drugs could be defined as medicinal supermolecules formed by two or more molecules through non-covalent bonds. So far a lot of supermolecules as chemical drugs have been widely used in clinics. Supermolecules as chemical drugs, i.e. supramolecular chemical drugs or supramolecular drugs, which might have the excellences of lower cost, shorter period, higher potential as clinical drugs for their successful research and development, may possess higher bioavailability, better biocompatibility and drug-targeting, fewer multidrug-resistances, lower toxicity, less adverse effect, and better curative effects as well as safety, and therefore exhibit wide potential application. These overwhelming advantages have drawn enormous special attention. This paper gives the definition of supramolecular drugs, proposes the concept of supramolecular chemical drugs, and systematically reviews the recent advances in the research and development of supermolecules, including organic and inorganic complex ones as chemical drugs in the area of antitumor, anti-inflammatory, analgesic, antimalarial, antibacterial, antifungal, antivirus, anti-epileptic, cardiovascular agents and magnetic resonance imaging agents and so on. The perspectives of the foreseeable future and potential application of supramolecules as chemical drugs are also presented.
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Affiliation(s)
- ChengHe Zhou
- School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715 China
| | - LinLing Gan
- School of Pharmaceutical Sciences, Southwest University, Chongqing, 400715 China
| | - YiYi Zhang
- School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715 China
| | - FeiFei Zhang
- School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715 China
| | - GuangZhou Wang
- School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715 China
| | - Lei Jin
- School of Pharmaceutical Sciences, Southwest University, Chongqing, 400715 China
| | - RongXia Geng
- School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715 China
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Photodynamic activity of BAM-SiPc, an unsymmetrical bisamino silicon(IV) phthalocyanine, in tumour-bearing nude mice. Br J Pharmacol 2008; 154:4-12. [PMID: 18332853 DOI: 10.1038/bjp.2008.82] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND AND PURPOSE Ever since the discovery of photodynamic therapy, there has been a continuous search for more potent photosensitizers. Towards that end, we have synthesized a number of novel phthalocyanine derivatives. The unsymmetrical bisamino silicon(IV) phthalocyanine BAM-SiPc is one of the most potent compounds. In in vitro cell culture, it exhibits high phototoxicity against a number of cancer cell lines. EXPERIMENTAL APPROACH In the present investigation, the in vivo effect of BAM-SiPc was studied in the tumour-bearing nude mice model. The biodistribution of BAM-SiPc was followed to evaluate its tumour selectivity and rate of clearance. The tumour volume in the hepatocarcinoma HepG2- and the colorectal adenocarcinoma HT29-bearing nude mice was measured after photodynamic therapy. The level of intrinsic toxicity induced was also investigated. Finally, the metabolism of BAM-SiPc in the 'normal' WRL68 liver cells and the hepatocarcinoma HepG2 cells was compared. KEY RESULTS The results not only showed significant tumour regression of HepG2 and growth inhibition of HT29 in the tumour-bearing nude mice, but also no apparent hepatic or cardiac injury with the protocol used. Histological analyses showed that apoptosis was induced in the solid tumour. BAM-SiPc could be metabolized by WRL68 liver cells but not by the hepatocarcinoma HepG2 cells. Unfortunately, BAM-SiPc did not show any specific targeting towards the tumour tissue. CONCLUSIONS AND IMPLICATIONS The efficiency of BAM-SiPc in inhibiting tumour growth makes it a good candidate for further evaluation. Enhancement of its uptake in tumour tissue by conjugation with biomolecules is currently under investigation.
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Prognon P, Kasselouri A, Desroches M, Blais J, Maillard P. Tétrapyrroles anticancéreux photosensibilisants : ou comment la photophysique devient mécanisme d’action. ANNALES PHARMACEUTIQUES FRANÇAISES 2008; 66:71-6. [DOI: 10.1016/j.pharma.2008.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Accepted: 03/26/2008] [Indexed: 11/25/2022]
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Obata M, Hirohara S, Sharyo K, Alitomo H, Kajiwara K, Ogata SI, Tanihara M, Ohtsuki C, Yano S. Sugar-dependent photodynamic effect of glycoconjugated porphyrins: A study on photocytotoxicity, photophysical properties and binding behavior to bovine serum albumin (BSA). Biochim Biophys Acta Gen Subj 2007; 1770:1204-11. [PMID: 17490818 DOI: 10.1016/j.bbagen.2007.03.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2006] [Revised: 03/21/2007] [Accepted: 03/22/2007] [Indexed: 12/19/2022]
Abstract
The photocytotoxicity of four glycoconjugated porphyrins, namely 5,10,15,20-tetrakis[4-(beta-D-glucopyranosyloxy)phenyl]porphyrin (p-1a), 5,10,15,20-tetrakis[4-(beta-D-galactopyranosyloxy)phenyl]porphyrin (p-1b), 5,10,15,20-tetrakis[4-(beta-D-xylopyranosyloxy)phenyl]porphyrin (p-1c) and 5,10,15,20-tetrakis[4-(beta-D-arabinopyranosyloxy)phenyl]porphyrin (p-1d), was evaluated in HeLa cells in the concentration range from 1 to 7 microM using a light dose of 16 J x cm(-2) with a wavelength greater than 500 nm. The photocytotoxicity depends on the sugar moieties, and increases in the order of p-1d<p-1a<p-1b<p-1c. The order of the photocytotoxicity is at variance with that of the cellular uptake reported previously. On the other hand, the photophysical properties of the glycoconjugated porphyrins also depends on the sugar moieties in physiological media such as phosphate buffered saline (PBS) containing 10 wt.% bovine serum albumin (BSA). In particular, the oscillator strength in the range above 500 nm increases in the order of p-1d=p-1a<p-1c<p-1b, which is good agreement with the order of the photocytotoxicity in HeLa cells. The interaction between the glycoconjugated porphyrins and BSA was evaluated by means of electronic absorption, fluorometric and circular dichroic (CD) titrations. Fluorometric titration showed no differences in the apparent binding constants, K, between the glycoconjugated porphyrins p-1a, p-1b, p-1c and p-1d. On the other hand, the number of binding sites, n, depends on the sugar moieties of the glycoconjugated porphyrin, and increases in the order of p-1b<p-1a<p-1d<p-1c. CD titration was also characterized by the n value determined by fluorometric titration, suggesting the n value is a good descriptor for the interaction between glycoconjugated porphyrins and BSA. However, it was found that the n value was poorly related to the photophysical properties in physiological media and the photocytotoxicity. Even though the role of the sugar moieties on the photodynamic effect is not fully understood, the photophysical properties of the glycoconjugated porphyrins are strongly modulated by the physiological media resulting in the sugar-dependent photocytotoxicity.
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Affiliation(s)
- Makoto Obata
- Division of Material Science, Graduate School of Humanities and Sciences, Nara Women's University, Kitauoyanishimachi, Nara 630-8506, Japan.
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