ABSTRACT
Alzheimer disease (AD) is the most prevalent form of dementia that develops spontaneously in the elderly. It's worth mentioning that as people age, the epigenetic profile of the central nervous system cells changes, which may speed up the development of various neurodegenerative disorders including AD. Histone deacetylases (HDACs) are a class of epigenetic enzymes that can control gene expression without altering the gene sequence. Moreover, a promising strategy for multi-target hybrid design was proposed to potentially improve drug efficacy and reduce side effects. These hybrids are monocular drugs that contain various pharmacophore components and have the ability to bind to different targets at the same time. The HDACs ability to synergistically boost the performance of other anti-AD drugs, as well as the ease with which HDACs inhibitor cap group, can be modified. This has prompted numerous medicinal chemists to design a novel generation of HDACs multi-target inhibitors. Different HDACs inhibitors and other ones such as acetylcholinesterase, butyryl-cholinesterase, phosphodiesterase 9, phosphodiesterase 5 or glycogen synthase kinase 3ß inhibitors were merged into hybrids for treatment of AD. This review goes over the scientific rationale for targeting HDACs along with several other crucial targets in AD therapy. This review presents the latest hybrids of HDACs and other AD target pharmacophores.
ABSTRACT
BACKGROUND/AIM: Photodynamic therapy (PDT) is a relatively non-invasive anti-cancer therapy that employs a photosensitizer with a specific wavelength of light, causing a photochemical reaction that releases free radicals, thereby inducing tumor cell necrosis via oxidative stress. The oxygen molecule reaches the singlet excited state through efficient energy transfer from an excited triplet state of the photosensitizer. Heavy atoms are frequently introduced in photosensitizers for efficiently generating reactive oxygen species (ROS) in PDT, known as the heavy atom effect. However, metal-complexed photosensitizers often show low water-solubility. To overcome this limitation and produce ROS effectively, we focused on the better solubility of photosensitizers with heavy metals bound within the chlorin skeleton and conjugated with glucose in this study. MATERIALS AND METHODS: We established maltotriose (Mal3)-conjugation with heavy metallochlorins [M (Mal3-chlorin), M=Pt or Pd)] and evaluated its anti-tumor effect. RESULTS: M (Mal3-chlorin) showed effective ROS production and singlet oxygen induction. Consequently, these cytotoxic factors caused effective anti-tumor effects and induced morphological changes, followed by cell death in vitro. In a xenograft tumor mouse model, PDT with M (Mal3-chlorin) showed tumor growth suppression. CONCLUSION: M (Mal3-Chlorin) might be an excellent glucose-conjugated chlorin because of its strong anti-tumor PDT effect.
Subject(s)
Photochemotherapy , Porphyrins , Trisaccharides , Humans , Animals , Mice , Photosensitizing Agents/pharmacology , Reactive Oxygen Species , Metals , Porphyrins/pharmacology , Disease Models, Animal , GlucoseABSTRACT
The eradication of multifactorial diseases, such as cancer, requires the design of drug candidates that attack multiple targets that contribute to the progression and proliferation of such diseases. Here, 1,5-diarylpyrazole derivatives bearing vanillin or sulfanilamide are developed as potential dual inhibitors of epidermal growth factor receptor (EGFR)/c-Jun N-terminal kinase 2 (JNK-2) for possible anticancer activity. These derivatives inhibited the growths of DLD-1, HeLa, K-562, SUIT-2 and HepG2 cancer cell lines, with minimum concentration required to inhibit half of the cellular growth (IC50) values of 2.7-63 µM. The tests confirmed that 5b and 5d were potent JNK-2 inhibitors, with IC50 of 2.0 and 0.9 µM, respectively, whereas 6 h selectively inhibited EGFR protein kinase (EGFR-PK) (IC50 = 1.7 µM). Notably, 6c inhibited both kinases, with IC50 values of 2.7 and 3.0 µM against EGFR-PK and JNK-2, respectively, offering a reference for designing mutual inhibitors of EGFR/JNK-2. The docking studies revealed the ability of the pyrazole ring to bind to the hinge region of the ATP binding site, thereby supporting the experimental inhibitory results. Furthermore, the developed compounds could induce apoptosis and induce cell cycle arrest at different cell phases.
Subject(s)
Antineoplastic Agents , Humans , Molecular Structure , Structure-Activity Relationship , Antineoplastic Agents/chemistry , Drug Screening Assays, Antitumor , Protein Kinase Inhibitors/chemistry , ErbB Receptors , Cell Proliferation , Cell Line, Tumor , Molecular Docking Simulation , Drug DesignABSTRACT
The group-transfer polymerization (GTP) of N,N-bis(2-methoxyethyl)acrylamide (MOEAm) initiated by Me2EtSiH in the hydrosilylation-promoted method and by silylketene acetal (SKA) in the conventional method proceeded in a controlled/living manner to provide poly(N,N-bis(2-methoxyethyl)acrylamide) (PMOEAm) and PMOEAm with the SKA residue at the α-chain end (MCIP-PMOEAm), respectively. PMOEAm-b-poly(N,N-dimethylacrylamide) (PDMAm) and PMOEAm-s-PDMAm and PMOEAm-b-poly(N,N-bis(2-ethoxyethyl)acrylamide) (PEOEAm) and PMOEAm-s-PEOEAm were synthesized by the block and random group-transfer copolymerization of MOEAm and N,N-dimethylacrylamide or N,N-bis(2-ethoxyethyl)acrylamide. The homo- and copolymer structures affected the thermoresponsive properties; the cloud point temperature (Tcp) increasing by decreasing the degree of polymerization (x). The chain-end group in PMOEAm affected the Tcp with PMOEAmx > MCIP-PMOEAmx. The Tcp of statistical copolymers was higher than that of block copolymers, with PMOEAmx-s-PDMAmy > PMOEAmx-b-PDMAmy and PMOEAmx-s-PEOEAmy > PMOEAmx-b-PEOEAmy.
ABSTRACT
BACKGROUND: The spread of coronavirus disease 2019 (COVID-19), which began in 2020, has had a major impact on healthcare systems. The spread of COVID-19 has been reported to have affected the readiness to treat patients with burns worldwide. However, the existing reports have evaluated burn care status within a limited time period during the pandemic, and no report clarifies the change in the impact of infection status on burn care from the beginning of the pandemic to the present. METHODS: Japanese Society for Burn Injuries-accredited burn care facilities were surveyed using questionnaires on April 9-23, 2020; June 23-July 6, 2020; July 9-21, 2021; and January 21-31, 2022. Differences between groups were evaluated using Friedman's test or Bonferroni's multiple comparison test, as appropriate. RESULTS: From the 103 facilities included in the study, we received 85, 55, 56, and 58 responses in the first, second, third, and fourth surveys, respectively. We could continuously observe 34 facilities. The rate of acceptance of patients with severe burns improved significantly over time (P < 0.05). However, in the second and third surveys, there was an increase in the number of respondents who did not accept patients with burns irrespective of COVID-19 status. CONCLUSIONS: The number of facilities treating patients with burns who have COVID-19 is increasing; however, COVID-19 care may negatively impact routine burn care. It is necessary to continuously examine medical resource allocation through methods such as information sharing by academic societies.
Subject(s)
Burns , COVID-19 , Humans , Pandemics , Japan , Burns/therapy , Surveys and Questionnaires , Burn UnitsABSTRACT
In this paper, we describe a comprehensive study of the thermoresponsive properties of statistic copolymers and multiblock copolymers synthesized by poly(glycidol)s (PG) and poly(ethyl glycidyl ether) (PEGE) with different copolymerization methods. These copolymers were first synthesized by ring-opening polymerization (ROP), which was initiated by tert-butylbenzyl alcohol (tBBA) and 1-tert-butyl-4,4,4-tris(dimethylamino)-2,2-bis[tris(dimethylamino)phosphoranylidenamino]-2Λ5,4Λ5-catenadi(phosphazene) (t-Bu-P4) as the catalyst, and then the inherent protective groups were removed to obtain the copolymers without any specific chain end groups. The thermoresponsive property of the statistic copolymer PGx-stat-PEGEy was compared with the diblock copolymer PGx-b-PEGEy, and the triblock copolymers were compared with the pentablock copolymers. Among them, PG-stat-PEGE, PG-b-PEGE-b-PG-b-PEGE-b-PG, and PEGE-b-PG-b-PEGE-b-PG-b-PEGE, and even the specific ratio of PEGE-b-PG-b-PEGE, exhibited LCST-type phase transitions in water, which were characterized by cloud point (Tcp). Although the ratio of x to y affected the value of the Tcp of PGx-stat-PEGEy, we found that the disorder of the copolymer has a decisive effect on the phase-transition behavior. The phase-transition behaviors of PG-b-PEGE, part of PEGE-b-PG-b-PEGE, and PG-b-PEGE-b-PG copolymers in water present a two-stage phase transition, that is, firstly LCST-type and then the upper critical solution temperature (UCST)-like phase transition. In addition, we have extended the research on the thermoresponsive properties of EGE homopolymers without specific α-chain ends.
ABSTRACT
Protein kinases have grown over the past few years as a crucial target for different cancer types. With the multifactorial nature of cancer, and the fast development of drug resistance for conventional chemotherapeutics, a strategy for designing multi-target agents was suggested to potentially increase drug efficacy, minimize side effects and retain the proper pharmacokinetic properties. Kinase inhibitors were used extensively in such strategy. Different kinase inhibitor agents which target EGFR, VEGFR, c-Met, CDK, PDK and other targets were merged into hybrids with conventional chemotherapeutics such as tubulin polymerization and topoisomerase inhibitors. Other hybrids were designed gathering kinase inhibitors with targeted cancer therapy such as HDAC, PARP, HSP 90 inhibitors. Nitric oxide donor molecules were also merged with kinase inhibitors for cancer therapy. The current review presents the hybrids designed in the past five years discussing their design principles, results and highlights their future perspectives.
Subject(s)
Antineoplastic Agents/pharmacology , Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacology , Protein Kinases/metabolism , Antineoplastic Agents/chemistry , Humans , Molecular Structure , Neoplasms/metabolism , Protein Kinase Inhibitors/chemistryABSTRACT
Glycoconjugated chlorins represent a promising class of compounds that meet the requirements for the third-generation photosensitizer (PS) for photodynamic therapy (PDT). We have focused on the use of glucose (Glc) to improve the performance of the PS based on the Warburg effect-a phenomenon where tumors consume higher Glc levels than normal cells. However, as a matter of fact, Glc-conjugation has a poor efficacy in hydrophilic modification; thus, the resultant PS is not suitable for intravenous injection. In this study, a Glc-based oligosaccharide, such as maltotriose (Mal3), is conjugated to chlorin e6 (Ce6). The conjugation is assisted by two additional molecular tools, such as propargyl amine and a tetraethylene glycol (TEG) derivative. This route produced the target Mal3-Ce6 conjugate linked via the TEG spacer (Mal3-TEG-Ce6), which shows the required photoabsorption properties in the physiological media. The PDT test using canine mammary carcinoma (SNP) cells suggested that the antitumor activity of Mal3-TEG-Ce6 is extremely high. Furthermore, in vitro tests against mouse mammary carcinoma (EMT6) cells have been demonstrated, providing insights into the photocytotoxicity, subcellular localization, and analysis of cell death and reactive oxygen species (ROS) generation for the PDT system with Mal3-TEG-Ce6. Both apoptosis and necrosis of the EMT6 cells occur by ROS that is generated via the photochemical reaction between Mal3-TEG-Ce6 and molecular oxygen. Consequently, Mal3-TEG-Ce6 is shown to be a PS showing the currently desired properties.
ABSTRACT
The JNKs are members of mitogen-activated protein kinases (MAPK) which regulate many physiological processes including inflammatory responses, macrophages, cell proliferation, differentiation, survival, and death. It is increasingly clear that the continuous activation of JNKs has a role in cancer development and progression. Therefore, JNKs represent attractive oncogenic targets for cancer therapy using small molecule kinase inhibitors. Studies showed that the two major JNK proteins JNK1 and JNK2 have opposite functions in different types of cancers, which need more specification in the design of JNK inhibitors. Some of ATP- competitive and ATP non-competitive inhibitors have been developed and widely used in vitro, but this type of inhibitors lack selectivity and inhibits phosphorylation of all JNK substrates and may lead to cellular toxicity. In this review, we summarized and discussed the strategies of JNK binding inhibitors and the role of JNK signaling in the pathogenesis of different solid and hematological malignancies.
Subject(s)
JNK Mitogen-Activated Protein Kinases/antagonists & inhibitors , Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacology , Animals , Drug Design , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , MAP Kinase Signaling System/drug effects , Molecular Targeted Therapy , Neoplasms/enzymology , Protein Kinase Inhibitors/adverse effects , Signal Transduction/drug effectsABSTRACT
Two new series of 1,3,4-oxadiazole and coumarin derivatives based on pyrimidine-5-carbonitrile scaffold have been synthesized and evaluated for their COX-1/COX-2 inhibitory activity. Compounds 10c, 10e, 10h-j, 14e-f, 14i and 16 were found to be the most potent and selective inhibitors of COX-2 (IC50 0.041-0.081 µM, SI 139.74-321.95). Eight compounds were further investigated for their in vivo anti-inflammatory activity. The most active derivatives 10c, 10j and 14e displayed superior in vivo anti-inflammatory activity (% edema inhibition 39.3-48.3, 1 h; 58.4-60.5, 2 h; 70.8-83.2, 3 h; 78.9-89.5, 4 h) to the reference drug celecoxib (% edema inhibition 38.0, 1 h; 48.8, 2 h; 58.4, 3 h; 65.4, 4 h). These derivatives were also tested for their ulcerogenic liability, compound 10j showed better safety profile with reference to celecoxib while 10c and 14e exhibited mild lesions. Molecular docking studies of 10c, 10j, and 14e in the COX-2 active site revealed similar orientation and binding interactions as selective COX-2 inhibitors with a higher liability to access the selectivity side pocket.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Cyclooxygenase 2 Inhibitors/pharmacology , Cyclooxygenase 2/metabolism , Molecular Docking Simulation , Pyrimidines/pharmacology , Ulcer/drug therapy , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Cyclooxygenase 2 Inhibitors/chemical synthesis , Cyclooxygenase 2 Inhibitors/chemistry , Dose-Response Relationship, Drug , Drug Design , Humans , Molecular Structure , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Sheep , Structure-Activity Relationship , Ulcer/metabolism , Ulcer/pathologyABSTRACT
A photosensitizer is a molecular drug for photodynamic diagnosis and photodynamic therapy (PDT) against cancer. Many studies have developed photosensitizers, but improvements in their cost, efficacy, and side effects are needed for better PDT of patients. In the present study, we developed a novel photosensitizer ß-mannose-conjugated chlorin e6 (ß-M-Ce6) and investigated its PDT effects in human glioblastoma U251 cells. U251 cells were incubated with ß-M-Ce6, followed by laser irradiation. Cell viability was determined using the Cell Counting Kit-8 assay. The PDT effects of ß-M-Ce6 were compared with those of talaporfin sodium (TS) and our previously reported photosensitizer ß-glucose-conjugated chlorin e6 (ß-G-Ce6). Cellular uptake of each photosensitizer and subcellular distribution were analyzed by fluorescence microscopy. ß-M-Ce6 showed 1000× more potent PDT effects than those of TS, and these were similar to those of ß-G-Ce6. ß-M-Ce6 accumulation in U251 cells was much faster than TS accumulation and distributed to several organelles such as the Golgi apparatus, mitochondria, and lysosomes. This rapid cellular uptake was inhibited by low temperature, which suggested that ß-M-Ce6 uptake uses biological machinery. ß-M-Ce6 showed potent PDT anti-cancer effects compared with clinically approved TS, which is a possible candidate as a next generation photosensitizer in cancer therapy.
ABSTRACT
The microwave-assisted heating reaction of N-acetyl glucosamine (GlcNAc) in sulfolane is described. The reaction produces two major products that are assignable to 1,6-anhydro-2-acetamido-2-deoxy-ß-d-glucopyranose (AGPNAc) and 1,6-anhydro-2-acetamido-2-deoxy-ß-d-glucofuranose (AGFNAc). In order to reveal a general feature of the system, the 3, 5, and 10 min reactions were performed at 140, 160, 180, 200, and 220 °C to clarify the time course changes in the conversion of GlcNAc and the yields of the two produced 1,6-anhydrosugars. Temperature is a crucial factor that significantly affects the conversion of GlcNAc. The yields of AGPNAc and AGFNAc are also drastically changed depending on the reaction conditions. The 5-min reaction at 200 °C is shown to be the optimal condition to generate the 1,6-anhydrosugars with a high efficiency in which AGPNAc and AGFNAc are produced in the yields of 21% and 44%, respectively. Consequently, the microwave-assisted heating reaction of GlcNAc in sulfolane is shown to be a simple and promising pathway to generate 1,6-anhydrosugars consisting of amino monosaccharide backbones, which have high potentials as raw materials leading to biological oligosaccharides and biomimetic polysaccharides.
Subject(s)
Acetylglucosamine/chemistry , Heating , Microwaves , Oligosaccharides/chemistry , Thiophenes/chemistry , Acetylation , Chromatography, High Pressure Liquid , Molecular StructureABSTRACT
We here present a direct link between the reaction mechanisms for the ring-expansion "vinyl" polymerization system and atomic force microscopy (AFM) observations. The brush-modification clearly discriminates the desired cyclic species with the contour lengths (Lc) of 28-132 nm and molar masses (MAFM) of 60.2-283 kg mol-1 from the other linear ones. The 293 polymer blushes observed in a 1.0 µm × 1.0 µm AFM image are individually characterized, eventually providing clear answers about the mechanisms of this rare polymerization system, which include ring-expansion vinyl polymerizations to generate cyclic polymers, fusions of the generated cycles to form multimers, and their scission to form linear or ring-opened species. The relationship between the molecular chain lengths and the cyclic versus linear morphologies is highlighted.
ABSTRACT
Surface modifier-free hybridization of ZrO2 nanoparticles (NPs) with epoxy-based polymers is demonstrated for the first time to afford highly transparent and refractive bulk materials. This is achieved by a unique and versatile hybridization via the one-pot direct phase transfer of ZrO2 NPs from water to epoxy monomers without any aggregation followed by curing with anhydride. Three types of representative epoxy monomers, bisphenol A diglycidyl ether (BADGE), 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexane carboxylate (CEL), and 1,3,5-tris(3-(oxiran-2-yl)propyl)-1,3,5-triazinane-2,4,6-trione (TEPIC), are used to produce transparent viscous dispersions. The resulting ZrO2 NPs are thoroughly characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), and solid-state 13C CP/MAS NMR measurements. The results from DLS and TEM analyses indicate nanodispersion of ZrO2 into epoxy monomers as a continuous medium. A surface modification mechanism and the binding fashion during phase transfer are proposed based on the FT-IR and solid-state 13C CP/MAS NMR measurements. Epoxy-based hybrid materials with high transparency and refractive index are successfully fabricated by heat curing or polymerizing a mixture of monomers containing epoxy-functionalized ZrO2 NPs and methylhexahydrophthalic anhydride in the presence of a phosphoric catalyst. The TEM and small-angle X-ray scattering measurements of the hybrids show a nanodispersion of ZrO2 in the epoxy networks. The refractive index at 594 nm ( n594) increases up to 1.765 for BADGE-based hybrids, 1.667 for CEL-based hybrids, and 1.693 for TEPIC-based hybrids. Their refractive indices and Abbe's numbers are quantitatively described by the Lorentz-Lorenz effective medium expansion theory. Their transmissivity is also reasonably explained using Fresnel refraction, Rayleigh scattering, and the Lambert-Beer theories. This surface modifier-free hybridization provides a versatile, fascinating, and promising method for synthesizing a variety of epoxy-based hybrid materials.
ABSTRACT
Macrocyclic polymers present an important class of macromolecules, displaying the reduced radius of gyration or impossibility to entangle. A rare approach for their synthesis is the ring expansion-controlled radical "vinyl" polymerization, starting from a cyclic alkoxyamine. We here describe ring-expansion radical crossover reactions of cyclic alkoxyamines which run in parallel to chain-propagation reactions in the polymerization system. The radical crossover reactions extensively occurred at 105â»125 °C, eventually producing high molecular weight polymers with multiple inherent dynamic covalent bonds (NOC bonds). A subsequent ring-contraction radical crossover reaction and the second ring-expansion radical crossover reaction are also described. The major products for the respective three stages were shown to possess cyclic morphologies by the molecular weight profiles and the residual ratios for the NOC bonds (φ in %). In particular, the high φ values ranging from ca. 80% to 98% were achieved for this cyclic alkoxyamine system. This result verifies the high availability of this system as a tool demonstrating the ring-expansion "vinyl" polymerization that allows them to produce macrocyclic polymers via a one-step vinyl polymerization.
ABSTRACT
Peritoneal dissemination is a major clinical issue associated with dismal prognosis and poor quality of life for patients with pancreatic cancer; however, no effective treatment strategies have been established. Herein, we evaluated the effects of photodynamic therapy (PDT) with maltotriose-conjugated chlorin (Mal3-chlorin) in culture and in a peritoneal disseminated mice model of pancreatic cancer. The Mal3-chlorin was prepared as a water-soluble chlorin derivative conjugated with four Mal3 molecules to improve cancer selectivity. In vitro, Mal3-chlorin showed superior uptake into pancreatic cancer cells compared with talaporfin, which is clinically used. Moreover, the strong cytotoxic effects of PDT with Mal3-chlorin occurred via apoptosis and reactive oxygen species generation, whereas Mal3-chlorin alone did not cause any cytotoxicity in pancreatic cancer cells. Notably, using a peritoneal disseminated mice model, we demonstrated that Mal3-chlorin accumulated in xenograft tumors and suppressed both tumor growth and ascites formation with PDT. Furthermore, PDT with Mal3-chlorin induced robust apoptosis in peritoneal disseminated tumors, as indicated by immunohistochemistry. Taken together, these findings implicate Mal3-chlorin as a potential next-generation photosensitizer for PDT and the basis of a new strategy for managing peritoneal dissemination of pancreatic cancer. Mol Cancer Ther; 16(6); 1124-32. ©2017 AACR.
Subject(s)
Pancreatic Neoplasms/pathology , Peritoneal Neoplasms/secondary , Photochemotherapy , Photosensitizing Agents/pharmacology , Porphyrins/pharmacology , Trisaccharides , Animals , Apoptosis/drug effects , Caspases/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/radiation effects , Disease Models, Animal , Female , Humans , Mice , Molecular Structure , Peritoneal Neoplasms/therapy , Photosensitizing Agents/chemistry , Porphyrins/chemistry , Reactive Oxygen Species/metabolism , Trisaccharides/chemistry , Xenograft Model Antitumor AssaysABSTRACT
Photodynamic therapy (PDT) is a Food and Drug Administration authorized method for cancer treatment, which uses photosensitizer and laser photo-irradiation to generate reactive oxygen species to induce cell death in tumors. Photosensitizers have been progressively developed, from first to third generation, with improvements in cell specificity, reduced side effects and toxicity, increased sensitivity for irradiation and reduced persistence of photosensitizer in healthy cells. These improvements have been achieved by basic comparative experiments between current and novel photosensitizers using cell lines; however, photosensitizers should be carefully evaluated because they may have cell type specificity. In the present study, we compared a third-generation photosensitizer, ß-mannose-conjugated chlorin (ß-M-chlorin), with the second generation, talaporfin sodium (NPe6), using seven different rat and human cell lines and a neuronal/glial primary culture prepared from rat embryos. NPe6 was more effective than ß-M-chlorin in human-derived cell lines, and ß-M-chlorin was more effective than NPe6 in rat primary cultures and rat-derived cell lines, except for the rat pheochromocytoma cell line, PC12. These differences of phototoxicity in different cell types are not because of differences in photosensitivity between the photosensitizers, but rather are associated with different distribution and accumulation rates in the different cell types. These data suggest that evaluation of photosensitizers for PDT should be carried out using as large a variety of cell types as possible because each photosensitizer may have cell type specificity.
Subject(s)
Antineoplastic Agents/pharmacology , Light , Mannose/pharmacology , Photochemotherapy , Photosensitizing Agents/pharmacology , Porphyrins/pharmacology , Animals , Cell Line , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/radiation effects , Cells, Cultured , Humans , Mannose/chemistry , Neurons/drug effects , Neurons/metabolism , Neurons/radiation effects , PC12 Cells , Porphyrins/chemistry , Rats , Rats, WistarABSTRACT
Photodynamic therapy (PDT) exploits light interactions and photosensitizers to induce cytotoxic reactive oxygen species. Photodynamic diagnosis (PDD) uses the phenomenon of photosensitizer emitting fluorescence to distinguish some tumors from normal tissue. The standard photosensitizer used for PDD is 5-aminolevulinic acid (5-ALA), although it is not entirely satisfactory. We previously reported glucose-conjugated chlorin (G-chlorin) as a more effective photosensitizer than another widely used photosensitizer, talaporfin sodium (TS); however, G-chlorin is hydrophobic. We synthesized oligosaccharide-conjugated chlorin (O-chlorin) with improved water-solubility. We report herein on its accumulation and cytotoxicity. O-chlorin was synthesized and examined for solubility. Flow cytometric analysis was performed to evaluate O-chlorin accumulation in cancer cells. To evaluate the intracellular localization of photosensitizer, cells were stained with O-chlorin and organelle-specific fluorescent probes. We then measured the in vitro fluorescence of various photosensitizers and the half-maximal inhibitory concentrations to evaluate effects in PDD and PDT, respectively. Xenograft tumor models were established, and antitumor and visibility effects were analyzed. O-chlorin was first shown to be hydrophilic. Flow cytometry then revealed a 20- to 40-times higher accumulation of O-chlorin in cancer cells than of TS, and a 7- to 23-times greater fluorescence than 5-ALA. In vitro, the cytotoxicity of O-chlorin PDT was stronger than that of TS PDT, and O-chlorin tended to accumulate in lysosomes. In vivo, O-chlorin showed the best effect in PDT and PDD compared to other photosensitizers.O-chlorin was hydrophilic and showed excellent tumor accumulation and fluorescence. O-chlorin is promising as a next-generation bifunctional photosensitizer candidate for both PDT and PDD.
Subject(s)
Esophageal Neoplasms/drug therapy , Photochemotherapy/methods , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Porphyrins/chemistry , Porphyrins/pharmacology , Animals , Cell Line, Tumor , Esophageal Neoplasms/metabolism , Female , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Photosensitizing Agents/pharmacokinetics , Porphyrins/pharmacokinetics , Solubility , Water/chemistry , Xenograft Model Antitumor AssaysABSTRACT
Background. Images of head CT for the supratentorial compartment are sometimes recommended to be reconstructed with a thickness of 8-10 mm to achieve lesion conspicuity. However, additional images of a thin slice may not be routinely provided for patients with trauma in the emergency room (ER). We investigated the diagnostic sensitivity of a head CT, where axial images were 10 mm thick slices, in cases of linear skull fractures. Methods. Two trauma surgeons retrospectively reviewed head CT with 10 mm slices and skull X-rays of patients admitted to the ER that were diagnosed with a linear skull fracture. All patients had undergone both head CT and skull X-rays (n = 410). Result. The diagnostic sensitivity of head CT with a thickness of sequential 10 mm was 89% for all linear skull fractures but only 56% for horizontal fractures. This CT technique with 10 mm slices missed 6% of patients with linear skull fractures. False-negative diagnoses were significantly more frequent for older (≥55 years) than for young (<15 years) individuals (p = 0.048). Conclusions. A routine head CT of the supratentorial region for patients in the ER with head injuries requires both thick-slice images to visualize cerebral hemispheres and thin-slice images to detect skull fractures of the cranial vault.
ABSTRACT
Photoactive molecules with the frameworks of chlorin and/or porphyrin possessing four perfluorinated aromatic rings were conjugated with maltotriose (Mal3) via the nucleophilic aromatic substitution reaction and subsequent deprotection reaction of the oligosaccharide moieties. The resulting oligosaccharide-conjugated molecules are ultimately improved as compared to the previously reported monosaccharide-counterparts in terms of water-solubility. In particular, a water-soluble chlorin derivative surrounded by four Mal3 molecules showed an excellent biocompatibility, strong photoabsorption in the longer wavelength regions, and a very high photocytotoxicity. Thus, the present synthetic route combined with the use of an oligosaccharide was shown to be a straightforward strategy to develop a third generation photosensitizer for photodynamic therapy (PDT).