Okayama University Medical School Acta Medica Okayama 0386-300X 80 2 2026 Involvement of ADAM12 in TGF-β1-Induced Proliferation of Rheumatoid Arthritis Synovial Fibroblasts 75 83 EN Deting Lin Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiro Horita Department of Orthopaedic Surgery, Faculty of Medical Development Field, Okayama University Masahito Watanabe Department of Orthopaedic Surgery, Muscat Orthopaedic Clinic Joe Hasei Medical Information and Assistive Technology Development, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takashi Ohtsuki Medical Technology, Graduate School of Health Sciences, Okayama University Noriaki Otsuka Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Chinatsu Ichikawa Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Noriyuki Shimizu Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shuichi Naniwa Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Keiichiro Nishida Division of Chronic Pain Medicine and Division of Comprehensive Rheumatology, Locomotive Pain Center, Faculty of Medical Development Field, Okayama University Original Article 10.18926/AMO/70450 A disintegrin and metalloproteinase 12 (ADAM12) is known to be involved in chondrocyte proliferation and is upregulated in the synovial tissue of osteoarthritis (OA). However, the underlying mechanisms of ADAM12 on rheumatoid arthritis (RA) synovial cell proliferation remain unknown. Here, we investigated the role of ADAM12 in the proliferation of RA synovial fibroblasts (RASFs). The expression and localization of ADAM12 in RA synovial tissues were examined by immunohistochemistry and compared with OA and healthy control (HC) synovial tissues. The effect of inflammatory cytokines (TNF-α, TGF-β1, and PDGF-BB) on ADAM12 expression in RASFs from RA patients was examined by real-time RT-PCR. The effect of ADAM12 knock-down by ADAM12 siRNA and ADAM12 overexpression on cell proliferation of RASFs were examined by WST-1 assay. ADAM12 was identified predominantly in RA synovial tissue rather than OA and HC synovial tissues. Stimulation with TGF-β1 upregulated the expression of ADAM12 and cell proliferation of RASFs. ADAM12 siRNA suppressed TGF-β1-induced cell proliferation of RASFs, while ADAM12 overexpression promoted the cell proliferation of RASFs. These findings demonstrate that ADAM12 may have a key role in TGF-β1-induced cell proliferation of synovial fibroblasts in patients with RA. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2211-7156 25 2026 Peptide nanomicelles for NIR light-dependent siRNA delivery 103265 EN Taufik Fatwa Nur Hakim Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mizuki Kitamatsu Department of Applied Chemistry, Kindai University Shoumu Fujimoto Department of Applied Chemistry, Kindai University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University The peptide amphiphile PA8, derived from the GAVILRR peptide, was developed as a carrier for small interfering RNA (siRNA) delivery; however, its RNA interference (RNAi) efficacy was limited owing to predominant endocytotic uptake. In this study, the RNAi efficiency of PA8 nanomicelle/siRNA complexes was enhanced by modifying the nanomicelles with the photosensitizer DY750 and the tumor-homing peptide iRGD. The conjugation of DY750 to the nanomicelles facilitated endosomal escape of the nanomicelle/siRNA complexes, enabling the cytosolic release of siRNA. Additionally, the incorporation of iRGD improved RNAi delivery efficiency in the AsPC-1 pancreatic ductal adenocarcinoma cell line. PA8-DY750-iRGD nanomicelle complexes loaded with siRNA against polo-like kinase 1 (PLK1) achieved an 80% reduction in PLK1 mRNA levels in AsPC-1 cells and a moderate 28% knockdown in NCI-N87 gastric cancer cells. Notably, no RNAi effect was observed in noncancerous 1C3D3 pancreatic cells or HEK293T kidney cells, underscoring the selectivity of this system for AsPC-1 cells. These findings highlight the potential of PA8-DY750-iRGD nanomicelle complexes as a targeted therapeutic platform for specific cancers, particularly pancreatic cancer. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2045-2322 16 1 2026 Liquid–liquid phase separation by caged coacervating peptides 10464 EN Akinari Bando Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mizuki Kitamatsu Department of Applied Chemistry, Kindai University Yuuki Kanazaki Department of Applied Chemistry, Kindai University Rika Tojo Department of Applied Chemistry, Kindai University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Liquid–liquid phase separation is an important biomolecular process in the formation of membraneless intracellular organelles that has inspired the development of artificial droplet systems. We developed caged coacervating peptides (CCPs) based on a histidine-rich squid beak protein sequence. The peptides were caged with a photodeprotectable (7-diethylaminocoumarin-4-yl)methoxycarbonyl group. The CCPs formed coacervates in the caged state and were partially dispersed upon blue-light irradiation. Photo-uncaging occurred rapidly, inducing coacervate dispersion. A mutant CCP with reduced π–π interactions exhibited efficient photo-dependent disassembly and enabled the encapsulation and release of a fluorescently labeled adenosine 5′-triphosphate (Bodipy-ATP) upon irradiation. These CCPs offer an efficient light-controlled approach for biomolecular encapsulation within coacervates and targeted drug delivery. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0022-2623 69 5 2026 Discovery of Thermal Sensitizers That Inhibit Heat-Induced SAFB Granule Formation 5944 5955 EN Yuji Furutani Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Natsuki Shimasaki Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Riko Yamada Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazunori Watanabe Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Hyperthermia is a minimally invasive cancer treatment based on heat stress-induced apoptosis. Its therapeutic efficacy, however, is often limited by tumor heterogeneity and acquired thermotolerance. Therefore, combination strategies involving hyperthermia and chemotherapy have been developed to enhance the therapeutic efficacy. Previously, we showed that SB366791 enhanced heat-induced apoptosis by inhibiting heat stress-induced scaffold attachment factor B (SAFB) granule formation, although its proapoptotic activity was insufficient. Therefore, we screened to identify novel compounds that enhance heat-induced apoptosis by suppressing SAFB granule formation. We identified four hit compounds that inhibited SAFB granule formation, all exhibiting thermal enhancement ratios > 1.0─that significantly enhanced heat-induced apoptosis efficiency. Additionally, the tumor volume in mice treated with a combination of Z19024498 and hyperthermia was significantly smaller than that in mice treated with hyperthermia or Z19024498. These results indicate that the identified compounds, specifically Z19024498, have potential as thermal sensitizers for hyperthermia therapy. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2079-6374 16 1 2026 Magnetic Detection of Cancer Cells Using Tumor-Homing Peptide-Modified Magnetic Nanoparticles 45 EN Shengli Zhou Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Yuji Furutani Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kei Yamashita Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Sakuya Kako Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toshihiko Kiwa Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Magnetic nanoparticles (MNPs) provide a platform for target detection because of their magnetic responsiveness to alternating magnetic fields (AMFs). We developed a detection method using MNPs modified with tumor-homing peptides (THPs), PL1 and PL3, which selectively bind to protein components enriched in malignant tissues. THP-MNPs were synthesized using maleimide-PEG-NHS linkers and characterized using transmission electron microscopy. Human glioblastoma cancer U87MG and normal tissue-derived HEK293 cells were incubated with THP-MNPs, and the magnetic signals were measured using a high-temperature superconducting quantum interference device (SQUID) magnetometer under an AMF (1.06 kHz). Dark-field microscopy confirmed the preferential binding of THP-MNPs to U87MG cells. In the absence of cells, THP-MNPs exhibited AMF-dependent signal enhancement, which correlated with particle size reduction due to THP release. This increase was completely suppressed in the presence of U87MG cells, indicating a strong THP-mediated interaction. PL3-MNPs exhibited superior discrimination between malignant and non-malignant cells. These results demonstrate that SQUID-based magnetic measurements using THP-MNPs enable rapid and label-free cancer cell detection. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-0520 23 27 2025 Fluorescence detection of DNA with a single-base mismatch by a Tm-independent peptide nucleic acid (PNA) twin probe 6557 6563 EN Koki Ishii Department of Applied Chemistry, Kindai University Hajime Shigeto Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Shohei Yamamura Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Yoshitane Imai Department of Applied Chemistry, Kindai University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mizuki Kitamatsu Department of Applied Chemistry, Kindai University There is a need to develop efficient methods for detecting target nucleic acids to enable the rapid diagnosis and early treatment of diseases. We previously demonstrated that a peptide nucleic acid (PNA) twin probe, consisting of two PNAs each containing a fluorescent dye, with pyrene at one end, detects target DNA sequence-specifically through pyrene excimer emission. In this study, to advance the development of this probe system, we further investigated the fluorescence properties of the PNA twin probe P1 and P2, and found that the excimer fluorescence was significantly reduced when a mismatched base in the DNA sequence was present at the site of P1 closest to the pyrene. In other words, this probe was found to detect single-base mismatches without taking into account the thermal stability of the PNA/DNA hybrid. The detection limit of this PNA twin probe for the single-base-mismatched DNA was 2.7 nM. In the future, this probe should lead to a method to detect point mutations in endogenous nucleic acids within cells. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2772-4174 13 2025 Photochemical internalization of mRNA using a photosensitizer and nucleic acid carriers 100242 EN Hayaki Maemoto Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ryohei Suzaki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Keiji Itaka Department of Biofunction Research, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University mRNA has great potential for therapeutic applications because it can encode a variety of proteins and antigens, in addition to advantages over DNA in terms of gene expression without genomic integration, nuclear localization, or transcription. However, therapeutic applications of mRNA require safe and effective delivery into target cells. Therefore, we aimed to investigate photochemical internalization (PCI) as a promising strategy for delivering mRNA to target cells. In this strategy, mRNA is taken up into cells by endocytosis, accumulates in endosomes, and is released in a light-dependent manner from the endosomes using an endosome-accumulating photosensitizer, aluminum phthalocyanine disulfonate (AlPcS2a), in combination with nucleic acid carrier molecules. We compared the efficacy of various nucleic acid carriers, including branched polyethyleneimine (bPEI) and poly{N'-[N-(2-aminoethyl)-2-aminoethyl] aspartamide} (PAsp(DET)) under the same conditions for PCI-based mRNA delivery. Our results indicated that bPEI and PAsp(DET) at low N/P ratios exhibited efficient light-enhancement of mRNA expression by PCI with AlPcS2a. Notably, bPEI exhibited the highest light-dependent mRNA delivery among the carriers evaluated (including cationic polymers, cationic peptides, and lipids), whereas PAsp(DET) showed promise for clinical use because of its lower toxicity compared with bPEI. This PCI strategy allows effective cytosolic mRNA delivery at low N/P ratios, thereby reducing cationic carrier molecule-induced cytotoxicity. This method allows spatiotemporal control of protein expression and holds potential for novel light-dependent mRNA therapies. Overall, this study provided valuable insights into optimizing mRNA delivery systems for therapeutic applications. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1661-6596 26 3 2025 LRP4 and Agrin Are Modulated by Cartilage Degeneration and Involved in β-Catenin Signaling in Human Articular Chondrocytes 1007 EN Shuichi Naniwa Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama University Keiichiro Nishida Locomotive Pain Center, Okayama University Hospital Aki Yoshida Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama University Yoshihisa Nasu Locomotive Pain Center, Okayama University Hospital Ryuichi Nakahara Locomotive Pain Center, Okayama University Hospital Takashi Ohtsuki Department of Medical Technology, Graduate School of Health Sciences, Okayama University Yoshifumi Hotta Department of Orthopaedic Surgery, Sayo Central Hospital Noriyuki Shimizu Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama University Chinatsu Ichikawa Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama University Deting Lin Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama University Noriaki Otsuka Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama University Toshifumi Ozaki Department of Orthopaedic Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University We investigated the roles of low-density lipoprotein receptor-related protein (LRP) 4 and its ligand Agrin in the pathophysiology of cartilage degeneration. Immunohistochemical analysis of human normal articular cartilage and cartilage tissues from patients with osteoarthritis (OA) obtained during surgery of the knee joint showed marked LRP4 expression in the early stages of OA, which then decreased with cartilage degeneration, whereas Agrin was consistently increased with cartilage degeneration. In normal human articular chondrocytes (NHACs), mild cyclic tensile strain (CTS) (0.5 Hz, 5% elongation, 2 h) increased the expression of LRP4 and aggrecan (ACAN), while intense CTS (0.5 Hz, 10% elongation, 6 h) increased the expression of Agrin without affecting LRP4 expression. Treatment with recombinant human (rh) Agrin downregulated the mRNA expression of LRP4 and ACAN, but upregulated the expression of LRP5/6, SRY-box transcription factor 9 (SOX9), Runt-related transcription factor 2 (RUNX2), and a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4). Immunocytochemistry and Western blot analysis showed that rhAgrin treatment upregulated the expression of β-catenin and SOX9. Agrin knockdown by siAGRN transfection partially reduced the nuclear protein expression of β-catenin, which was increased with intense CTS. LRP4 knockdown by siLRP4 transfection increased the expression of LRP5/6, SOX9, RUNX2, ADAMTS-4, and Agrin. These results suggested that intense CTS increases the expression of Agrin, which might interfere with the role of LRP4 in the inhibition of LRP5/6 and their downstream β-catenin signaling, leading to cartilage degeneration. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2073-4409 14 1 2025 Novel Drug Delivery Particles Can Provide Dual Effects on Cancer "Theranostics" in Boron Neutron Capture Therapy 60 EN Abdul Basith Fithroni Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Haruki Inoue Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Shengli Zhou Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Taufik Fatwa Nur Hakim Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Tada Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Minoru Suzuki Institute for Integrated Radiation and Nuclear Science, Kyoto University Yoshinori Sakurai Institute for Integrated Radiation and Nuclear Science, Kyoto University Manabu Ishimoto J-BEAM, Inc. Naoyuki Yamada Nihon Fukushi Fuiin Holding, Co., Ltd. Rani Sauriasari Faculty of Pharmacy, Universitas Indonesia Wolfgang A. G. Sauerwein Deutsche Gesellschaft für Bor-Neutroneneinfangtherapie DGBNCT e.V., University Hospital Essen, Klinik für Strahlentherapie Kazunori Watanabe Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Eiji Matsuura Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Boron (B) neutron capture therapy (BNCT) is a novel non-invasive targeted cancer therapy based on the nuclear capture reaction 10B (n, alpha) 7Li that enables the death of cancer cells without damaging neighboring normal cells. However, the development of clinically approved boron drugs remains challenging. We have previously reported on self-forming nanoparticles for drug delivery consisting of a biodegradable polymer, namely, “AB-type” Lactosome® nanoparticles (AB-Lac particles)- highly loaded with hydrophobic B compounds, namely o-Carborane (Carb) or 1,2-dihexyl-o-Carborane (diC6-Carb), and the latter (diC6-Carb) especially showed the “molecular glue” effect. Here we present in vivo and ex vivo studies with human pancreatic cancer (AsPC-1) cells to find therapeutically optimal formulas and the appropriate treatment conditions for these particles. The biodistribution of the particles was assessed by the tumor/normal tissue ratio (T/N) in terms of tumor/muscle (T/M) and tumor/blood (T/B) ratios using near-infrared fluorescence (NIRF) imaging with indocyanine green (ICG). The in vivo and ex vivo accumulation of B delivered by the injected AB-Lac particles in tumor lesions reached a maximum by 12 h post-injection. Irradiation studies conducted both in vitro and in vivo showed that AB-Lac particles-loaded with either 10B-Carb or 10B-diC6-Carb significantly inhibited the growth of AsPC-1 cancer cells or strongly inhibited their growth, with the latter method being significantly more effective. Surprisingly, a similar in vitro and in vivo irradiation study showed that ICG-labeled AB-Lac particles alone, i.e., without any 10B compounds, also revealed a significant inhibition. Therefore, we expect that our ICG-labeled AB-Lac particles-loaded with 10B compound(s) may be a novel and promising candidate for providing not only NIRF imaging for a practical diagnosis but also the dual therapeutic effects of induced cancer cell death, i.e., “theranostics”. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1661-6596 25 22 2024 Distribution and Incorporation of Extracellular Vesicles into Chondrocytes and Synoviocytes 11942 EN Takashi Ohtsuki Department of Medical Technology, Graduate School of Health Sciences, Okayama University Ikumi Sato Department of Medical Technology, Graduate School of Health Sciences, Okayama University Ren Takashita Department of Medical Technology, Graduate School of Health Sciences, Okayama University Shintaro Kodama Department of Medical Technology, Graduate School of Health Sciences, Okayama University Kentaro Ikemura Department of Medical Technology, Graduate School of Health Sciences, Okayama University Gabriel Opoku Department of Medical Technology, Graduate School of Health Sciences, Okayama University Shogo Watanabe Department of Medical Technology, Graduate School of Health Sciences, Okayama University Takayuki Furumatsu Department of Orthopedic Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Hiroshi Yamada Department of Neuroscience, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Mitsuru Ando Laboratory of Biomaterials, Institute for Life and Medical Sciences, Kyoto University Kazunari Akiyoshi Department of Immunology, Graduate School of Medicine, Kyoto University Keiichiro Nishida Department of Orthopedic Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Satoshi Hirohata Department of Medical Technology, Graduate School of Health Sciences, Okayama University Osteoarthritis (OA) is a chronic disease affecting over 500 million people worldwide. As the population ages and obesity rates rise, the societal burden of OA is increasing. Pro-inflammatory cytokines, particularly interleukin-1β, are implicated in the pathogenesis of OA. Recent studies suggest that crosstalk between cartilage and synovium contributes to OA development, but the mechanisms remain unclear. Extracellular vesicles (EVs) were purified from cell culture-conditioned medium via ultracentrifugation and confirmed using transmission electron microscopy, nanoparticle tracking analysis, and western blotting. We demonstrated that EVs were taken up by human synoviocytes and chondrocytes in vitro, while in vivo experiments revealed that fluorescent-labelled EVs injected into mouse joints were incorporated into chondrocytes and synoviocytes. EV uptake was significantly inhibited by dynamin-mediated endocytosis inhibitors, indicating that endocytosis plays a major role in this process. Additionally, co-culture experiments with HEK-293 cells expressing red fluorescent protein (RFP)-tagged CD9 and the chondrocytic cell line OUMS-27 confirmed the transfer of RFP-positive EVs across a 600-nm but not a 30-nm filter. These findings suggest that EVs from chondrocytes are released into joint fluid and taken up by cells within the cartilage, potentially facilitating communication between cartilage and synovium. The results underscore the importance of EVs in OA pathophysiology. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1420-3049 29 11 2024 In Vitro Study of Tumor-Homing Peptide-Modified Magnetic Nanoparticles for Magnetic Hyperthermia 2632 EN Shengli Zhou Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kaname Tsutsumiuchi College of Bioscience and Biotechnology, Chubu University Ritsuko Imai College of Bioscience and Biotechnology, Chubu University Yukiko Miki College of Bioscience and Biotechnology, Chubu University Anna Kondo College of Bioscience and Biotechnology, Chubu University Hiroshi Nakagawa College of Bioscience and Biotechnology, Chubu University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Cancer cells have higher heat sensitivity compared to normal cells; therefore, hyperthermia is a promising approach for cancer therapy because of its ability to selectively kill cancer cells by heating them. However, the specific and rapid heating of tumor tissues remains challenging. This study investigated the potential of magnetic nanoparticles (MNPs) modified with tumor-homing peptides (THPs), specifically PL1 and PL3, for tumor-specific magnetic hyperthermia therapy. The synthesis of THP-modified MNPs involved the attachment of PL1 and PL3 peptides to the surface of the MNPs, which facilitated enhanced tumor cell binding and internalization. Cell specificity studies revealed an increased uptake of PL1- and PL3-MNPs by tumor cells compared to unmodified MNPs, indicating their potential for targeted delivery. In vitro hyperthermia experiments demonstrated the efficacy of PL3-MNPs in inducing tumor cell death when exposed to an alternating magnetic field (AMF). Even without exposure to an AMF, an additional ferroptotic pathway was suggested to be mediated by the nanoparticles. Thus, this study suggests that THP-modified MNPs, particularly PL3-MNPs, hold promise as a targeted approach for tumor-specific magnetic hyperthermia therapy. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2227-9717 12 4 2024 Pyrene-Modified Cyclic Peptides Detect Cu2+ Ions by Fluorescence in Water 746 EN Yuhi Maekawa Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University Sora Sakura Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University Yuji Furutani Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Rento Fujihara Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University Hisashi Sugime Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mizuki Kitamatsu Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University The detection of metal ions is an option for maintaining water quality and diagnosing metal ion-related diseases. In this study, we successfully detected metal ions using fluorescent peptides in water. First, we prepared seven linear (L1-L7) and seven cyclic (C1-C7) peptides containing two pyrenyl (Pyr) units and assessed the response to various metal ions by fluorescence. The results indicated that C1, which contains a hexameric cyclic peptide moiety consisting of Pyr and Gly units, did not show a fluorescent response to metal ions, while the linear L1 corresponding to C1 showed a response to Cu2+, but its selectivity was found to be poor through a competition assay for each metal ion. We then assessed C2-C7 and L2-L7, in which Gly was replaced by His units at various positions in the same manner. The results showed that C2-C7 responded to Cu2+ in a manner dependent on the His position. Additionally, superior selectivity was observed in C7 through a competition assay. These results demonstrate that the structural restriction of peptides and the sequence affect the selective detection of Cu2+ and reveal that peptides with an appropriate structure can accomplish the fluorescent detection of Cu2+ specifically. No potential conflict of interest relevant to this article was reported.

nature portfolio Acta Medica Okayama 2045-2322 13 1 2023 Photo-dependent cytosolic delivery of shRNA into a single blastomere in a mouse embryo 13050 EN Yuka Ikawa Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takuya Wakai Department of Animal Science, Graduate of Environmental and Life Science, Okayama University Hiroaki Funahashi Department of Animal Science, Graduate of Environmental and Life Science, Okayama University Tet Htut Soe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Single-cell-specific delivery of small RNAs, such as short hairpin RNA (shRNA) and small noncoding RNAs, allows us to elucidate the roles of specific upregulation of RNA expression and RNAi-mediated gene suppression in early embryo development. The photoinduced cytosolic dispersion of RNA (PCDR) method that we previously reported can introduce small RNAs into the cytosol of photoirradiated cells and enable RNA delivery into a single-cell in a spatiotemporally specific manner. However, the PCDR method has only been applied to planer cultured cells and not to embryos. This study demonstrated that the PCDR method can be utilized for photo-dependent cytosolic shRNA delivery into a single blastomere and for single blastomere-specific RNA interference in mouse embryos. Our results indicate that PCDR is a promising approach for studying the developmental process of early embryogenesis. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 0003-2654 148 11 2023 FRET probe for detecting two mutations in one EGFR mRNA 2626 2632 EN Myat Thu Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kouta Yanai Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Hajime Shigeto Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Shohei Yamamura Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Technologies for visualizing and tracking RNA are essential in molecular biology, including in disease-related fields. In this study, we propose a novel probe set (DAt-probe and T-probe) that simultaneously detects two mutations in the same RNA using fluorescence resonance energy transfer (FRET). The DAt-probe carrying the fluorophore Atto488 and the quencher Dabcyl were used to detect a cancer mutation (exon19del), and the T-probe carrying the fluorophore Tamra was used to detect drug resistance mutations (T790M) in epidermal growth factor receptor (EGFR) mRNA. These probes were designed to induce FRET when both mutations were present in the mRNA. Gel electrophoresis confirmed that the two probes could efficiently bind to the mutant mRNA. We measured the FRET ratios using wild-type and double-mutant RNAs and found a significant difference between them. Even in living cells, the FRET probe could visualize mutant RNA. As a result, we conclude that this probe set provides a method for detecting two mutations in the single EGFR mRNA via FRET. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2073-4409 11 20 2022 Novel Self-Forming Nanosized DDS Particles for BNCT: Utilizing A Hydrophobic Boron Cluster and Its Molecular Glue Effect 3307 EN Abdul Basith Fithroni Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazuko Kobayashi Collaborative Research Center for OMIC, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Hirotaka Uji Department of Material Chemistry, Graduate School of Engineering, Kyoto University Manabu Ishimoto Fukushima SiC Applied Engineering Inc. Masaru Akehi Collaborative Research Center for OMIC, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Eiji Matsuura Department of Cell Chemistry, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University BNCT is a non-invasive cancer therapy that allows for cancer cell death without harming adjacent cells. However, the application is limited, owing to the challenges of working with clinically approved boron (B) compounds and drug delivery systems (DDS). To address the issues, we developed self-forming nanoparticles consisting of a biodegradable polymer, namely, "AB-type Lactosome (AB-Lac)" loaded with B compounds. Three carborane isomers (o-, m-, and p-carborane) and three related alkylated derivatives, i.e., 1,2-dimethy-o-carborane (diC1-Carb), 1,2-dihexyl-o-carborane (diC6-Carb), and 1,2-didodecyl-o-carborane (diC12-Carb), were separately loaded. diC6-Carb was highly loaded with AB-Lac particles, and their stability indicated the "molecular glue" effect. The efficiency of in vitro B uptake of diC6-Carb for BNCT was confirmed at non-cytotoxic concentration in several cancer cell lines. In vivo/ex vivo biodistribution studies indicated that the AB-Lac particles were remarkably accumulated within 72 h post-injection in the tumor lesions of mice bearing syngeneic breast cancer (4T1) cells, but the maximum accumulation was reached at 12 h. In ex vivo B biodistribution, the ratios of tumor/normal tissue (T/N) and tumor/blood (T/Bl) of the diC6-Carb-loaded particles remained stably high up to 72 h. Therefore, we propose the diC6-Carb-loaded AB-Lac particles as a promising candidate medicine for BNCT. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0960-894X 68 2022 Ultrasound-dependent RNAi using TatU1A-rose bengal conjugate 128767 EN Nanako Sumi Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Shota Nagahiro Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Eiji Nakata Institute of Advanced Energy, Kyoto University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Tat-U1A-rose bengal conjugate (TatU1A-RB) was prepared as an ultrasound-sensitive RNA carrier molecule. This molecule consists of Tat cell-penetrating peptide, U1A RNA-binding protein, and rose bengal as a sonosensitizer. We demonstrated that TatU1A-RB delivered RNA via the endocytosis pathway, which was followed by ultrasound-dependent endosomal escape and cytosolic dispersion of the RNA. A short hairpin RNA (shRNA) delivered by TatU1A-RB mediated RNA interference (RNAi) ultrasound-dependently. Even by ultrasound irradiation through blood cells, RNAi could be induced with TatU1A-RB and the shRNA. This ultrasound-dependent cytosolic RNA delivery method will serve as the basis for a new approach to nucleic acid therapeutics. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1422-0067 23 5 2022 Potential of a Novel Chemical Compound Targeting Matrix Metalloprotease-13 for Early Osteoarthritis: An In Vitro Study 2681 EN Junko Inagaki Department of Cell Chemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Airi Nakano Department of Medical Technology, Graduate School of Health Sciences, Okayama University Omer Faruk Hatipoglu Department of Pharmacology, Faculty of Medicine, Kindai University Yuka Ooka Department of Medical Technology, Graduate School of Health Sciences, Okayama University Yurina Tani Department of Medical Technology, Graduate School of Health Sciences, Okayama University Akane Miki Department of Medical Technology, Graduate School of Health Sciences, Okayama University Kentaro Ikemura Department of Medical Technology, Graduate School of Health Sciences, Okayama University Gabriel Opoku Department of Medical Technology, Graduate School of Health Sciences, Okayama University Ryosuke Ando Department of Medical Technology, Graduate School of Health Sciences, Okayama University Shintaro Kodama Department of Medical Technology, Graduate School of Health Sciences, Okayama University Takashi Ohtsuki Department of Medical Technology, Graduate School of Health Sciences, Okayama University Hirosuke Yamaji Heart Rhythm Center, Okayama Heart Clinic Shusei Yamamoto Department of Medical Technology, Graduate School of Health Sciences, Okayama University Eri Katsuyama Department of Medical Technology, Graduate School of Health Sciences, Okayama University Shogo Watanabe Department of Medical Technology, Graduate School of Health Sciences, Okayama University Satoshi Hirohata Department of Medical Technology, Graduate School of Health Sciences, Okayama University Osteoarthritis is a progressive disease characterized by cartilage destruction in the joints. Matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs) play key roles in osteoarthritis progression. In this study, we screened a chemical compound library to identify new drug candidates that target MMP and ADAMTS using a cytokine-stimulated OUMS-27 chondrosarcoma cells. By screening PCR-based mRNA expression, we selected 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide as a potential candidate. We found that 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide attenuated IL-1 beta-induced MMP13 mRNA expression in a dose-dependent manner, without causing serious cytotoxicity. Signaling pathway analysis revealed that 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide attenuated ERK- and p-38-phosphorylation as well as JNK phosphorylation. We then examined the additive effect of 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide in combination with low-dose betamethasone on IL-1 beta-stimulated cells. Combined treatment with 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide and betamethasone significantly attenuated MMP13 and ADAMTS9 mRNA expression. In conclusion, we identified a potential compound of interest that may help attenuate matrix-degrading enzymes in the early osteoarthritis-affected joints. No potential conflict of interest relevant to this article was reported.

Nature Portfolio Acta Medica Okayama 2045-2322 11 1 2021 Photocontrolled apoptosis induction using precursor miR-664a and an RNA carrier-conjugated with photosensitizer 14936 EN Kazunori Watanabe Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Tomoko Nawachi Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ruriko Okutani Department of Biomedical Engineering, Faculty of Engineering, Okayama University Takashi Ohtsuki Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Methods to spatially induce apoptosis are useful for cancer therapy. To control the induction of apoptosis, methods using light, such as photochemical internalization (PCI), have been developed. We hypothesized that photoinduced delivery of microRNAs (miRNAs) that regulate apoptosis could spatially induce apoptosis. In this study, we identified pre-miR-664a as a novel apoptosis-inducing miRNA via mitochondrial apoptotic pathway. Further, we demonstrated the utility of photoinduced cytosolic dispersion of RNA (PCDR), which is an intracellular RNA delivery method based on PCI. Indeed, apoptosis is spatially regulated by pre-miR-664a and PCDR. In addition, we found that apoptosis induced by pre-miR-664a delivered by PCDR was more rapid than that by lipofection. These results suggest that pre-miR-664a is a nucleic acid drug candidate for cancer therapy and PCDR and pre-miR-664a-based strategies have potential therapeutic uses for diseases affecting various cell types. No potential conflict of interest relevant to this article was reported.

Elsevier France-Editions Scientifiques Medicales e Acta Medica Okayama 0753-3322 139 2021 Osteopontin silencing attenuates bleomycin-induced murine pulmonary fibrosis by regulating epithelial-mesenchymal transition 111633 EN Omer Faruk Hatipoglu Department of Pharmacology, Faculty of Medicine, Kindai University Eyyup Uctepe Acıbadem Labmed Ankara Tissue Typing Laboratory Gabriel Opoku Department of Medical Technology, Graduate School of Health Sciences, Okayama University Hidenori Wake Department of Pharmacology, Faculty of Medicine, Kindai University Kentaro Ikemura Department of Medical Technology, Graduate School of Health Sciences, Okayama University Takashi Ohtsuki Department of Medical Technology, Graduate School of Health Sciences, Okayama University Junko Inagaki Department of Cell Chemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Mehmet Gunduz Department of Otolaryngology, Moriya Keiyu Hospital Esra Gunduz Department of Otolaryngology, Moriya Keiyu Hospital Shogo Watanabe Department of Medical Technology, Graduate School of Health Sciences, Okayama University Takashi Nishinaka Department of Pharmacology, Faculty of Medicine, Kindai University Hideo Takahashi Department of Pharmacology, Faculty of Medicine, Kindai University Satoshi Hirohata Department of Medical Technology, Graduate School of Health Sciences, Okayama University Idiopathic pulmonary fibrosis (IPF) is the most common and most deadly form of interstitial lung disease. Osteopontin (OPN), a matricellular protein with proinflammatory and profibrotic properties, plays a major role in several fibrotic diseases, including IPF; OPN is highly upregulated in patients' lung samples. In this study, we knocked down OPN in a bleomycin (BLM)-induced pulmonary fibrosis (PF) mouse model using small interfering RNA (siRNA) to determine whether the use of OPN siRNA is an effective therapeutic strategy for IPF. We found that fibrosing areas were significantly smaller in specimens from OPN siRNA-treated mice. The number of alveolar macrophages, neutrophils, and lymphocytes in bronchoalveolar lavage fluid was also reduced in OPN siRNA-treated mice. Regarding the expression of epithelial-mesenchymal transition (EMT)-related proteins, the administration of OPN-siRNA to BLM-treated mice upregulated E-cadherin expression and downregulated vimentin expression. Moreover, in vitro, we incubated the human alveolar adenocarcinoma cell line A549 with transforming growth factor (TGF)-beta 1 and subsequently transfected the cells with OPN siRNA. We found a significant upregulation of Col1A1, fibronectin, and vimentin after TGF-beta 1 stimulation in A549 cells. In contrast, a downregulation of Col1A1, fibronectin, and vimentin mRNA levels was observed in TGF-beta 1-stimulated OPN knockdown A549 cells. Therefore, the downregulation of OPN effectively reduced pulmonary fibrotic and EMT changes both in vitro and in vivo. Altogether, our results indicate that OPN siRNA exerts a protective effect on BLM-induced PF in mice. Our results provide a basis for the development of novel targeted therapeutic strategies for IPF. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1422-0067 22 9 2021 Inhibition of HSF1 and SAFB Granule Formation Enhances Apoptosis Induced by Heat Stress 4982 EN Kazunori Watanabe Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Stress resistance mechanisms include upregulation of heat shock proteins (HSPs) and formation of granules. Stress-induced granules are classified into stress granules and nuclear stress bodies (nSBs). The present study examined the involvement of nSB formation in thermal resistance. We used chemical compounds that inhibit heat shock transcription factor 1 (HSF1) and scaffold attachment factor B (SAFB) granule formation and determined their effect on granule formation and HSP expression in HeLa cells. We found that formation of HSF1 and SAFB granules was inhibited by 2,5-hexanediol. We also found that suppression of HSF1 and SAFB granule formation enhanced heat stress-induced apoptosis. In addition, the upregulation of HSP27 and HSP70 during heat stress recovery was suppressed by 2,5-hexanediol. Our results suggested that the formation of HSF1 and SAFB granules was likely to be involved in the upregulation of HSP27 and HSP70 during heat stress recovery. Thus, the formation of HSF1 and SAFB granules was involved in thermal resistance. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 00223549 110 2021 Lactosome-Conjugated siRNA Nanoparticles for Photo-Enhanced Gene Silencing in Cancer Cells 1788 1798 EN Melissa Siaw Han Lim Yuki Nishiyama Takashi Ohtsuki Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazunori Watanabe Graduate School of Natural Science and Technology, Okayama University Hirotsugu Kobuchi Kazuko Kobayashi Collaborative Research Center (OMIC), Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Eiji Matsuura The A3B-type Lactosome comprised of poly(sarcosine)3-block-poly(l-lactic acid), a biocompatible and biodegradable polymeric nanomicelle, was reported to accumulate in tumors in vivo via the enhanced permeability and retention (EPR) effect. Recently, the cellular uptake of Lactosome particles was enhanced through the incorporation of a cell-penetrating peptide (CPP), L7EB1. However, the ability of Lactosome as a drug delivery carrier has not been established. Herein, we have developed a method to conjugate the A3B-type Lactosome with ATP-binding cassette transporter G2 (ABCG2) siRNA for inducing in vitro apoptosis in the cancer cell lines PANC-1 and NCI-H226. The L7EB1 peptide facilitates the cellular uptake efficiency of Lactosome but does not deliver siRNA into cytosol. To establish the photoinduced cytosolic dispersion of siRNA, a photosensitizer loaded L7EB1-Lactosome was prepared, and the photosensitizer 5,10,15,20-tetra-kis(pentafluorophenyl)porphyrin (TPFPP) showed superiority in photoinduced cytosolic dispersion. We exploited the combined effects of enhanced cellular uptake by L7EB1 and photoinduced endosomal escape by TPFPP to efficiently deliver ABCG2 siRNA into the cytosol for gene silencing. Moreover, the silencing of ABCG2, a protoporphyrin IX (PpIX) transporter, also mediated photoinduced cell death via 5-aminolevulinic acid (ALA)-mediated PpIX accumulated photodynamic therapy (PDT). The synergistic capability of the L7EB1/TPFPP/siRNA-Lactosome complex enabled both gene silencing and PDT. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2075-1729 11 2 2021 A Novel 89Zr-labeled DDS Device Utilizing Human IgG Variant (scFv): “Lactosome” Nanoparticle-Based Theranostics for PET Imaging and Targeted Therapy 158 EN Melissa Siaw Han Lim Department of Cell Chemistry, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Fumiaki Takenaka Collaborative Research Centre for OMIC, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Kazuko Kobayashi Collaborative Research Centre for OMIC, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Masaru Akehi Collaborative Research Centre for OMIC, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Hirotaka Uji Department of Material Chemistry, Graduate School of Engineering, Kyoto University Hirotsugu Kobuchi Department of Cell Chemistry, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Takanori Sasaki Collaborative Research Centre for OMIC, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Eiichi Ozeki Technology Research Laboratory, Shimadzu Corporation Eiji Matsuura Department of Cell Chemistry, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University “Theranostics,” a new concept of medical advances featuring a fusion of therapeutic and diagnostic systems, provides promising prospects in personalized medicine, especially cancer. The theranostics system comprises a novel 89Zr-labeled drug delivery system (DDS), derived from the novel biodegradable polymeric micelle, “Lactosome” nanoparticles conjugated with specific shortened IgG variant, and aims to successfully deliver therapeutically effective molecules, such as the apoptosis-inducing small interfering RNA (siRNA) intracellularly while offering simultaneous tumor visualization via PET imaging. A 27 kDa-human single chain variable fragment (scFv) of IgG to establish clinically applicable PET imaging and theranostics in cancer medicine was fabricated to target mesothelin (MSLN), a 40 kDa-differentiation-related cell surface glycoprotein antigen, which is frequently and highly expressed by malignant tumors. This system coupled with the cell penetrating peptide (CPP)-modified and photosensitizer (e.g., 5, 10, 15, 20-tetrakis (4-aminophenyl) porphyrin (TPP))-loaded Lactosome particles for photochemical internalized (PCI) driven intracellular siRNA delivery and the combination of 5-aminolevulinic acid (ALA) photodynamic therapy (PDT) offers a promising nano-theranostic-based cancer therapy via its targeted apoptosis-inducing feature. This review focuses on the combined advances in nanotechnology and material sciences utilizing the “89Zr-labeled CPP and TPP-loaded Lactosome particles” and future directions based on important milestones and recent developments in this platform. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1420-3049 26 1 2020 Photoinduced Endosomal Escape Mechanism: A View from Photochemical Internalization Mediated by CPP-Photosensitizer Conjugates 36 EN Tet Htut Soe Department of Biotechnology, Mandalay Technological University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Endosomal escape in cell-penetrating peptide (CPP)-based drug/macromolecule delivery systems is frequently insufficient. The CPP-fused molecules tend to remain trapped inside endosomes and end up being degraded rather than delivered into the cytosol. One of the methods for endosomal escape of CPP-fused molecules is photochemical internalization (PCI), which is based on the use of light and a photosensitizer and relies on photoinduced endosomal membrane destabilization to release the cargo molecule. Currently, it remains unclear how this delivery strategy behaves after photostimulation. Recent findings, including our studies using CPP-cargo-photosensitizer conjugates, have shed light on the photoinduced endosomal escape mechanism. In this review, we discuss the structural design of CPP-photosensitizer and CPP-cargo-photosensitizer conjugates, and the PCI mechanism underlying their application. No potential conflict of interest relevant to this article was reported.

Nature Research Acta Medica Okayama 2045-2322 10 1 2020 Cell cycle dependence of apoptosis photo-triggered using peptide-photosensitizer conjugate 19087 EN Hyungjin Kim Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Sho Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mizuki Kitamatsu Department of Applied Chemistry, Kindai University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Investigation of the relevance between cell cycle status and the bioactivity of exogenously delivered biomacromolecules is hindered by their time-consuming cell internalization and the cytotoxicity of transfection methods. In this study, we addressed these problems by utilizing the photochemical internalization (PCI) method using a peptide/protein-photosensitizer conjugate, which enables immediate cytoplasmic internalization of the bioactive peptides/proteins in a light-dependent manner with low cytotoxicity. To identify the cell-cycle dependent apoptosis, a TatBim peptide-photosensitizer conjugate (TatBim-PS) with apoptotic activity was photo-dependently internalized into HeLa cells expressing a fluorescent ubiquitination-based cell cycle indicator (Fucci2). Upon irradiation, cytoplasmic TatBim-PS internalization exceeded 95% for all cells classified in the G(1), S, and G(2)/M cell cycle phases with no significant differences between groups. TatBim-PS-mediated apoptosis was more efficiently triggered by photoirradiation in the G(1)/S transition than in the G(1) and S/G(2)/M phases, suggesting high sensitivity of the former phase to Bim-induced apoptosis. Thus, the cell cycle dependence of Bim peptide-induced apoptosis was successfully investigated using Fucci2 indicator and the PCI method. Since PCI-mediated cytoplasmic internalization of peptides is rapid and does not span multiple cell cycle phases, the Fucci-PCI method constitutes a promising tool for analyzing the cell cycle dependence of peptides/protein functions. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1422-0067 21 9 2020 Induction of CEMIP in Chondrocytes by Inflammatory Cytokines: Underlying Mechanisms and Potential Involvement in Osteoarthritis 3140 EN Takashi Ohtsuki Department of Medical Technology, Graduate School of Health Sciences, Okayama University Omer F. Hatipoglu Department of Medical Technology, Graduate School of Health Sciences, Okayama University Keiichi Asano Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Junko Inagaki Department of Cell Chemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Keiichiro Nishida Department of Orthopaediac Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Satoshi Hirohata Department of Medical Technology, Graduate School of Health Sciences, Okayama University In patients with osteoarthritis (OA), there is a decrease in both the concentration and molecular size of hyaluronan (HA) in the synovial fluid and cartilage. Cell migration-inducing hyaluronidase 1 (CEMIP), also known as hyaluronan (HA)-binding protein involved in HA depolymerization (HYBID), was recently reported as an HA depolymerization-related molecule expressed in the cartilage of patients with OA. However, the underlying mechanism of CEMIP regulation is not well understood. We found that CEMIP expression was transiently increased by interleukine-1 beta (IL-1 beta) stimulation in chondrocytic cells. We also observed that ERK activation and NF-kappa B nuclear translocation were involved in the induction of CEMIP by IL-1 beta. In addition, both administration of HA and mechanical strain attenuated the CEMIP induction in IL-1 beta-stimulated chondrocytes. In conclusion, we clarified the regulatory mechanism of CEMIP in chondrocytes by inflammatory cytokines and suggested the potential involvement in osteoarthritis development. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 00144827 383 2 2019 Mechanical strain attenuates cytokine-induced ADAMTS9 expression via transient receptor potential vanilloid type 1 111556 EN Takashi Ohtsuki Department of Medical Technology, Graduate School of Health Sciences, Okayama University Akira Shinaoka Department of Human Morphology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kanae Kumagishi-Shinaoka Department of Human Morphology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Keiichi Asano Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Omer Faruk Hatipoglu Department of Medical Technology, Graduate School of Health Sciences, Okayama University Junko Inagaki Department of Cell Chemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ken Takahashi Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshitaka Oohashi Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Keiichiro Nishida Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Keiji Naruse Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Satoshi Hirohata Department of Medical Technology, Graduate School of Health Sciences, Okayama University The synovial fluids of patients with osteoarthritis (OA) contain elevated levels of inflammatory cytokines, which induce the expression of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) and of the matrix metalloproteinase (MMP) in chondrocytes. Mechanical strain has varying effects on organisms depending on the strength, cycle, and duration of the stressor; however, it is unclear under inflammatory stimulation how mechanical strain act on. Here, we show that mechanical strain attenuates inflammatory cytokine-induced expression of matrix-degrading enzymes. Cyclic tensile strain (CTS), as a mechanical stressor, attenuated interleukin (IL)-1β and tumor necrosis factor (TNF)-α-induced mRNA expression of ADAMTS4, ADAMTS9, and MMP-13 in normal chondrocytes (NHAC-kn) and in a chondrocytic cell line (OUMS-27). This effect was abolished by treating cells with mechano-gated channel inhibitors, such as gadolinium, transient receptor potential (TRP) family inhibitor, ruthenium red, and with pharmacological and small interfering RNA-mediated TRPV1 inhibition. Furthermore, nuclear factor κB (NF-κB) translocation from the cytoplasm to the nucleus resulting from cytokine stimulation was also abolished by CTS. These findings suggest that mechanosensors such as the TRPV protein are potential therapeutic targets in treating OA. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2041-1723 7 2016 Phototriggered protein syntheses by using (7-diethylaminocoumarin-4-yl)methoxycarbonyl-caged aminoacyl tRNAs 12501 EN Takashi Ohtsuki Department of Biomedical Engineering, Okayama University Shigeto Kanzaki Department of Biomedical Engineering, Okayama University Sae Nishimura Department of Biomedical Engineering, Okayama University Yoshio Kunihiro Department of Biomedical Engineering, Okayama University Masahiko Sisido Department of Biomedical Engineering, Okayama University Kazunori Watanabe Department of Biomedical Engineering, Okayama University The possibility of spatiotemporally photocontrolling translation holds considerable promise for studies on the biological roles of local translation in cells and tissues. Here we report caged aminoacyl-tRNAs (aa-tRNAs) synthesized using a (7-diethylaminocoumarin-4-yl)methoxycarbonyl (DEACM)-cage compound. DEACM-caged aa-tRNA does not spontaneously deacylate for at least 4 h in neutral aqueous solution, and does not bind to the elongation factor Tu. On irradiation at ∼405 nm at 125 mW cm(-2), DEACM-aa-tRNA is converted into active aa-tRNA with a half-life of 19 s. Notably, this rapid uncaging induced by visible light does not impair the translation system. Translation is photoinduced when DEACM-aa-tRNA carrying a CCCG or a CUA anticodon is uncaged in the presence of mRNAs harbouring a CGGG four-base codon or a UAG amber codon, respectively. Protein synthesis is phototriggered in several model systems, including an in vitro translation system, an agarose gel, in liposomes and in mammalian cells. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2045-2322 5 2015 The molecular mechanism of photochemical internalization of cell penetrating peptide-cargo-photosensitizer conjugates. 18577 18577 EN Takashi Ohtsuki Department of Medical Bioengineering, Okayama University Shunya Miki Department of Medical Bioengineering, Okayama University Shouhei Kobayashi Advanced ICT Research Institute Kobe, NICT Tokuko Haraguchi Advanced ICT Research Institute Kobe, NICT Eiji Nakata Institute of Advanced Energy, Kyoto University Kazutaka Hirakawa Department of Applied Chemistry and Biochemical Engineering, Graduate School of Engineering, Shizuoka University Kensuke Sumita Department of Medical Bioengineering, Okayama University Kazunori Watanabe Department of Medical Bioengineering, Okayama University Shigetoshi Okazaki Department of Medical Spectroscopy, Hamamatsu University School of Medicine In many drug delivery strategies, an inefficient transfer of macromolecules such as proteins and nucleic acids to the cytosol often occurs because of their endosomal entrapment. One of the methods to overcome this problem is photochemical internalization, which is achieved using a photosensitizer and light to facilitate the endosomal escape of the macromolecule. In this study, we examined the molecular mechanism of photochemical internalization of cell penetrating peptide-cargo (macromolecule)-photosensitizer conjugates. We measured the photophysical properties of eight dyes (photosensitizer candidates) and determined the respective endosomal escape efficiencies using these dyes. Correlation plots between these factors indicated that the photogenerated (1)O2 molecules from photosensitizers were highly related to the endosomal escape efficiencies. The contribution of (1)O2 was confirmed using (1)O2 quenchers. In addition, time-lapse fluorescence imaging showed that the photoinduced endosomal escape occurred at a few seconds to a few minutes after irradiation (much longer than (1)O2 lifetime), and that the pH increased in the endosome prior to the endosomal escape of the macromolecule. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2041-1723 7 2016 Phototriggered protein syntheses by using (7-diethylaminocoumarin-4-yl)methoxycarbonyl-caged aminoacyl tRNAs 12501 12501 EN Takashi Ohtsuki Department of Biomedical Engineering, Okayama University Shigeto Kanzaki Department of Biomedical Engineering, Okayama University Sae Nishimura Department of Biomedical Engineering, Okayama University Yoshio Kunihiro Department of Biomedical Engineering, Okayama University Masahiko Sisido Department of Biomedical Engineering, Okayama University Kazunori Watanabe Department of Biomedical Engineering, Okayama University The possibility of spatiotemporally photocontrolling translation holds considerable promise for studies on the biological roles of local translation in cells and tissues. Here we report caged aminoacyl-tRNAs (aa-tRNAs) synthesized using a (7-diethylaminocoumarin-4-yl)methoxycarbonyl (DEACM)-cage compound. DEACM-caged aa-tRNA does not spontaneously deacylate for at least 4 h in neutral aqueous solution, and does not bind to the elongation factor Tu. On irradiation at ∼405 nm at 125 mW cm(-2), DEACM-aa-tRNA is converted into active aa-tRNA with a half-life of 19 s. Notably, this rapid uncaging induced by visible light does not impair the translation system. Translation is photoinduced when DEACM-aa-tRNA carrying a CCCG or a CUA anticodon is uncaged in the presence of mRNAs harbouring a CGGG four-base codon or a UAG amber codon, respectively. Protein synthesis is phototriggered in several model systems, including an in vitro translation system, an agarose gel, in liposomes and in mammalian cells. No potential conflict of interest relevant to this article was reported.

Zoological Society of Japan Acta Medica Okayama 0289-0003 22 9 2005 Organ-Specific and Age-Dependent Expression of Insulin-like Growth Factor-I (IGF-I) mRNA Variants: IGF-IA and IB mRNAs in the Mouse 1011 1021 EN Takashi Ohtsuki Mariko Otsuki Yousuke Murakami Tetsuya Maekawa Takashi Yamamoto Koji Akasaka Sakae Takeuchi Sumio Takahashi Insulin-like growth factor-I (IGF-I) gene generates several IGF-I mRNA variants by alternative splicing. Two promoters are present in mouse IGF-I gene. Each promoter encodes two IGF-I mRNA variants (IGF-IA and IGF-IB mRNAs). Variants differ by the presence (IGF-IB) or absence (IGF-IA) of a 52-bp insert in the E domain-coding region. Functional differences among IGF-I mRNAs, and regulatory mechanisms for alternative splicing of IGF-I mRNA are not yet known. We analyzed the expression of mouse IGF-IA and IGF-IB mRNAs using SYBR Green real-time RT-PCR. In the liver, IGF-I mRNA expression increased from 10 days of age to 45 days. In the uterus and ovary, IGF-I mRNA expression increased from 21 days of age, and then decreased at 45 days. In the kidney, IGF-I mRNA expression decreased from 10 days of age. IGF-IA mRNA levels were higher than IGF-IB mRNA levels in all organs examined. Estradiol-17 beta (E2) treatment in ovariectomized mice increased uterine IGF-IA and IGF-IB mRNA levels from 3 hr after injection, and highest levels for both mRNAs were detected at 6 hr, and relative increase was greater for IGF-IB mRNA than for IGF-IA mRNA. These results suggest that expression of IGF-I mRNA variants is regulated in organ-specific and age-dependent manners, and estrogen is involved in the change of IGF-I mRNA variant expression. No potential conflict of interest relevant to this article was reported.

Zoological Society of Japan Acta Medica Okayama 0289-0003 24 3 2007 Alternative Leader-Exon Usage in Mouse IGF-I mRNA Variants: Class 1 and Class 2 IGF-I mRNAs 241 247 EN Takashi Ohtsuki Mariko Otsuki Yousuke Murakami Kensaku Hirata Sakae Takeuchi Sumio Takahashi The mouse IGF-I gene contains six exons, and exon 1 and exon 2 gene are considered to be leader exons. The regulatory mechanism of alternative usage of the leader exons is unclear in mice. The present study, was aimed at clarifying changes in class 1 (derived from exon 1) and class 2 (derived from exon 2) IGF-I mRNA expression in mice under various conditions. Both class 1 and class 2 IGF-I mRNAs were expressed in the mouse uterus, liver and kidney, and class 1 IGF-I mRNA was the major transcript in all organs studied. In the uterus, both class 1 and class 2 IGF-I mRNA expression changed markedly during the estrous cycle, with the highest level at proestrus, but in the liver and kidney there were no significant changes in IGF-I mRNA expression during the estrous cycle. Estrogen treatment increased both class 1 and class 2 IGF-I mRNA levels in the uterus of ovariectomized mice, but class 1 mRNA expression increased more in response to estrogen treatment than class 2 mRNA expression. These findings suggest that estrogen stimulates IGF-I gene expression in, uterine cells, and that a promoter involved in transcription of class 1 IGF-I mRNA is more responsive to estrogen. In conclusion, the present study revealed that two leader exons of mouse IGF-I gene are used in the uterus, liver and kidney. IGF-I mRNA levels of both classes changed during the estrous cycle in the uterus, but not in the liver or kidney. Estrogen increased IGF-I mRNA levels of both classes in the uterus. No potential conflict of interest relevant to this article was reported.

Pergamon-Elsevier Science Ltd. Acta Medica Okayama 0040-4020 66 51 2010 Synthesis of pyrrolidine-based oxy-peptide nucleic acids carrying four types of nucleobases and their transport into cytoplasm 9659 9666 EN Mizuki Kitamatsu Akiko Takahashi Takashi Ohtsuki Masahiko Sisido We synthesized 16 pyrrolidine-based oxy-peptide nucleic acid (POPNA) monomers carrying four different nucleobases onto four different stereoisomers of pyrrolidine rings. Using these monomers, we prepared POPNA oligomers, which formed sequence-specific hybrids with DNAs. The oligomer configurations influenced the hybrid stability. The oligomers were not taken into CHO cells. However, they could enter the cell cytoplasm when mixed with the influenza virus hemagglutinin peptide-arginine heptamer conjugate. No potential conflict of interest relevant to this article was reported.

Elsevier Ltd. Acta Medica Okayama 0960-894X 19 13 2009 Carrier PNA for shRNA delivery into cells 3410 3413 EN Mizuki Kitamatsu Takanori Kubo Rino Matsuzaki Tamaki Endoh Takashi Ohtsuki Masahiko Sisido A peptide nucleic acid (PNA)-cell-penetrating peptide (CPP) conjugate (carrier PNA) was used as 'bridgebuilder' to connect a CPP with an shRNA. The carrier PNA successfully formed a hybrid with an shRNA bearing complementary dangling bases and the shRNA was introduced into cells by the carrier PNA, and RNAi was induced by the shRNA. No potential conflict of interest relevant to this article was reported.

Pergamon-Elsevier Science Ltd, Acta Medica Okayama 0960-894X 21 1 2011 Antisense effect of pyrrolidine-based oxy-peptide nucleic acids in Escherichia coli 225 227 EN Mizuki Kitamatsu Shunsuke Kurami Takashi Ohtsuki Masahiko Sisido To investigate the antisense effect of a pyrrolidine-based oxy-peptide nucleic acid (POPNA), we carried out the LacZ reporter assay using a 12-mer trans-l-POPNA conjugated with a cell-penetrating peptide (antisense reagent). The antisense effect of the conjugated POPNA (inhibition of LacZ activity) was comparable to that shown by a Nielsen-type peptide nucleic acid. Furthermore, the conjugated POPNA could switch the LacZ activity over a wide range of ambient temperatures. No potential conflict of interest relevant to this article was reported.