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Naoki Sato,1,2 Yuya Nakamura,1,3 Shiho Yamadera,4 Masahiro Inagaki,1,5 Sachiyo Kenmotsu,5 Hiroshi Saito,4,6 Tatsunori Oguchi,1 Mayumi Tsuji,1 Hirokazu Chokki,1 Isao Ohsawa,3 Hiromichi Gotoh,3 Shinichi Iwai,6 Yuji Kiuchi1 1Department of Pharmacology, Showa University School of Medicine, Shinagawa-ku, Tokyo, Japan; 2Department of Research Center, Tanabe Pharmacy Inc., Tokyo, Japan; 3Department of Nephrology, Saiyu Soka Hospital, Soka City, Saitama-ken, Japan; 4Department of Hospital Pharmaceutics, Showa University School of Pharmacy, Shinagawa-ku, Tokyo, Japan; 5Fuculty of Arts and Sciences at Fujiyoshida, Showa University, Fujiyoshida City, Yamanashi-ken, Japan; 6Department of Healthcare and Regulatory Sciences, Showa University School of Pharmacy, Shinagawa-ku, Tokyo, JapanCorrespondence: Yuya NakamuraDepartment of Pharmacology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, JapanTel +81-3-3784-8125Fax +81-3-3787-4790Email y.nakamura@med.showa-u.ac.jpPurpose: Dipeptidyl peptidase-4 inhibitors, including linagliptin, prevent inflammation. However, the in vitro effects of linagliptin are unclear. Moreover, although linagliptin inhibits lipopolysaccharide (LPS)-induced inflammation, the anti-inflammatory effects of linagliptin in this context are not concentration-dependent. In the absence of LPS-binding protein (LBP), the pro-inflammatory effects of LPS involve pathways other than the Toll-like receptor (TLR) 4 pathway. Here, we aimed to determine the anti-inflammatory mechanisms of linagliptin in an experimental model in which LBP was added to the medium.Methods: Human U937 monocytes were cultured at 1 × 106 cells/mL in Roswell Park Memorial Institute medium and differentiated into macrophages using phorbol myristate acetate. All processes were carried out in medium containing 10% fetal bovine serum (FBS). After 48 hrs of culture, we replaced the medium and pretreated the cells with 100, 250, 500, or 2500 nM linagliptin for 1 hr. We exchanged the medium again, and the cells were treated with 1 ng/mL LPS with or without 100, 250, 500, or 2500 nM linagliptin. Interleukin (IL)-6 and LBP in the supernatant, nuclear factor (NF)-κB/p65 in the nucleus, and reactive oxygen species (ROS) in the cells, as important markers of the mechanism of inflammation induction by LPS, were measured using enzyme-linked immunosorbent assay kits.Results: Linagliptin significantly prevented LPS-stimulated IL-6 production and intranuclear NF-κB/p65 levels in a concentration-dependent manner. LPS-induced intracellular ROS levels were significantly decreased by linagliptin at all concentrations. LBP levels were markedly higher in FBS-containing medium than in medium without FBS. However, LBP levels did not change following administration of linagliptin and/or LPS.Conclusion: Concentration-dependent and -independent inflammatory suppression was observed following linagliptin treatment in the context of LPS-induced pro-inflammatory responses. Thus, our findings suggested that linagliptin induced two different mechanisms to repress inflammation, i.e., TLR4-dependent and -independent mechanisms.Keywords: linagliptin, lipopolysaccharide-binding protein, interleukin-6, intranuclear subunit of nuclear factor-κB/p65, reactive oxygen species

Sivakumar Balasubramanian,1 Aswathy Ravindran Girija,1 Yutaka Nagaoka,1 Seiki Iwai,1 Masashi Suzuki,1 Venugopal Kizhikkilot,2 Yasuhiko Yoshida,1 Toru Maekawa,1 Sakthikumar Dasappan Nair1 1Bio Nano Electronics Research Center, Graduate School of Interdisciplinary New Science, Toyo University, Kawagoe, Japan; 2Department of Respiratory Medicine, Sooriya Hospital, Chennai, India Abstract: The efficient targeting and therapeutic efficacy of a combination of drugs (curcumin and 5-Fluorouracil [5FU]) and magnetic nanoparticles encapsulated poly(D,L-lactic-co-glycolic acid) nanoparticles, functionalized with two cancer-specific ligands are discussed in our work. This multifunctional, highly specific nanoconjugate resulted in the superior uptake of nanoparticles by cancer cells. Upon magnetic hyperthermia, we could harness the advantages of incorporating magnetic nanoparticles that synergistically acted with the drugs to destroy cancer cells within a very short period of time. The remarkable multimodal efficacy attained by this therapeutic nanoformulation offers the potential for targeting, imaging, and treatment of cancer within a short period of time (120 minutes) by initiating early and late apoptosis. Keywords: nanotechnology, curcumin, 5FU, folate, transferrin, PLGA nanoparticle, magnetic hyperthermia

Srivani Veeranarayanan, Aby Cheruvathoor Poulose, M Sheikh Mohamed, Yutaka Nagaoka, Seiki Iwai, Yuya Nakagame, Shosaku Kashiwada, Yasuhiko Yoshida, Toru Maekawa, D Sakthi KumarBio Nano Electronics Research Centre, Graduate School of Interdisciplinary New Science, Toyo University, Kawagoe, JapanAbstract: This paper presents the synthesis of aqueous cadmium sulfide (CdS) quantum dots (QDs) and silica-encapsulated CdS QDs by reverse microemulsion method and utilized as targeted bio-optical probes. We report the role of CdS as an efficient cell tag with fluorescence on par with previously documented cadmium telluride and cadmium selenide QDs, which have been considered to impart high levels of toxicity. In this study, the toxicity of bare QDs was efficiently quenched by encapsulating them in a biocompatible coat of silica. The toxicity profile and uptake of bare CdS QDs and silica-coated QDs, along with the CD31-labeled, silica-coated CdS QDs on human umbilical vein endothelial cells and glioma cells, were investigated. The effect of size, along with the time-dependent cellular uptake of the nanomaterials, has also been emphasized. Enhanced, high-specificity imaging toward endothelial cell lines in comparison with glioma cells was achieved with CD31 antibody-conjugated nanoparticles. The silica-coated nanomaterials exhibited excellent biocompatibility and greater photostability inside live cells, in addition to possessing an extended shelf life. In vivo biocompatibility and localization study of silica-coated CdS QDs in medaka fish embryos, following direct nanoparticle exposure for 24 hours, authenticated the nanomaterials' high potential for in vivo imaging, augmented with superior biocompatibility. As expected, CdS QD-treated embryos showed 100% mortality, whereas the silica-coated QD-treated embryos stayed viable and healthy throughout and after the experiments, devoid of any deformities. We provide highly cogent and convincing evidence for such silica-coated QDs as a model nanoparticle in practice, to achieve in vitro and in vivo precision targeted imaging.Keywords: endothelial imaging, CD31, silica nanoparticle, CdS QDs, medaka embryos, biocompatibility