Biological and Pharmaceutical Bulletin
Online ISSN : 1347-5215
Print ISSN : 0918-6158
ISSN-L : 0918-6158
Volume 45, Issue 8
Displaying 1-32 of 32 articles from this issue
Review
  • Yu Sakurai
    2022 Volume 45 Issue 8 Pages 972-977
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Nucleic acid drugs can control gene expression and function in a manner different from that of conventional compounds. On the other hand, nucleic acids can be easily degraded in the in vivo circumstances. In addition, nucleic acids cannot penetrate cell membranes. Therefore, a drug delivery system (DDS) is essential to protect nucleic acid molecules until they reach the target cell and to release them efficiently inside the cell. In order to apply nucleic acid drugs to new cancer therapeutic strategies, the author has been developing a DDS that enables functional control of vascular endothelial cells that consist of the tumor microenvironment. The aim of my study is to develop lipid nanoparticles (LNPs) were modified with functional molecules that control their pharmacokinetics in vivo and intracellular fate to delivered small interfering RNA (siRNA) to tumor vasculature. By imparting pH-responsive membrane fusion properties to lipid nanoparticles, I have developed a system that responds to acidification in endosomes within cells and subsequently efficiently releases siRNA into the cytoplasm via membrane fusion, where siRNA molecules exhibit their function. In addition, by developing a method for presenting functional molecules, such as peptides, saccharides and so on, that recognize target cells on the surface of LNPs, I succeeded in establishing LNPs which internalize more efficiently into specific cells than off-target cells. Finally, by integrating these technologies, I developed an in vivo siRNA DDS that enables in vivo control of genes of interest in tumor vascular endothelial cells and succeeded in cancer therapy by regulating vascular function.

Current Topics - Emerging Roles of Lipid Mediators in Health Sciences
Current Topics: Reviews
  • Tsubasa Ochiai, Toshiya Honsawa, Yuka Sasaki, Shuntaro Hara
    2022 Volume 45 Issue 8 Pages 979-984
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Prostacyclin (PGI2) synthase (PGIS) and microsomal prostaglandin (PG) E synthase-1 (PGES-1) are PG terminal synthases which functionally couple with inducible cyclooxygenase-2 (COX-2) as their upstream enzymes to produce PGI2 and PGE2, respectively. Non-steroidal anti-inflammatory drugs exert their pharmacological effects by the inhibition of COX-2 and thereby suppression of the biosynthesis of these PGs. PGIS is abundantly expressed in vascular endothelial and smooth muscle cells and has been shown to be critical for regulation of platelet aggregation and vascular tone. In addition to its role in vascular regulation, PGIS has been shown to be expressed in inflammatory cells including macrophages, and the proinflammatory roles of PGIS has been demonstrated. On the other hand, several investigators have recently reported that PGIS functions as an anti-inflammatory mediator by macrophage polarization and have indicated that PGIS is an ambivalent regulator of inflammatory reactions. In this review, we summarize the current understanding of proinflammatory and anti-inflammatory functions of PGIS and discuss its potential as a novel anti-inflammatory therapeutic target.

  • Ko Fujimori
    2022 Volume 45 Issue 8 Pages 985-991
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Prostaglandins (PGs) are lipid-derived autacoids that are synthesized from arachidonic acid by the action of cyclooxygenases and PG terminal synthases. PGs consist of PGD2, PGE2, PGF, prostacyclin (PGI2), and thromboxane A2, which act through G protein-coupled receptors. PGs sustain homeostatic functions and exert a variety of pathophysiological roles to regulate the development of various diseases such as obesity and dyslipidemia. Adipocytes (fat cells) have the unique capacity to accumulate large amounts of lipids as energy source in lipid droplets. Adipogenesis is the process of differentiation from preadipocytes to mature adipocytes, which is regulated by various adipogenic transcription factors. Obesity is defined as an abnormal increase in adipose tissue mass and is considered to be a risk factor for the development of lifestyle-related diseases including cardiovascular disease, hyperlipidemia, and type 2 diabetes mellitus. This review summarizes insights into the roles of PGD2, PGF, and their synthases in the regulation of adipogenesis and obesity.

  • Tomoaki Inazumi, Yukihiko Sugimoto
    2022 Volume 45 Issue 8 Pages 992-997
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Prostanoids are a group of typical lipid mediators that are biosynthesized from arachidonic acid by the actions of cyclooxygenases and their subsequent terminal synthases. Prostanoids exert a wide variety of actions through their specific membrane receptors on target cells. In addition to their classical actions, including fever, pain, and inflammation, prostanoids have been shown to play pivotal roles in various biological processes, such as female reproduction and the maintenance of vascular and gut homeostasis. Moreover, recent research using mice deficient in each of the prostanoid receptors, or using agonists/antagonists specific for each receptor clarified novel actions of prostanoids that had long been unknown, and the mechanisms therein. In this review, we introduce recent advances in the fields of metabolic control by prostanoid receptors such as in adipocyte differentiation, lipolysis, and adipocyte browning in adipose tissues, and discuss the potential of prostanoid receptors as a treatment target for metabolic disorders.

  • Tatsuro Naganuma, Nodoka Fujinami, Makoto Arita
    2022 Volume 45 Issue 8 Pages 998-1007
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Epithelial tissues are mainly composed of epithelial cells, covering both internal and external surfaces of our body. To maintain epithelial homeostasis, cellular functions, such as proliferation, migration, and differentiation, are flexibly regulated in response to changes in the cellular status, thereby contributing to barrier formation, immune reaction, and wound closure. Polyunsaturated fatty acids (PUFAs) are precursors of various lipid mediators that maintain tissue homeostasis by exerting characteristic bioactivities. This review aimed to summarize the role of PUFA-derived lipid mediators in epithelial cell functions, mainly focusing on the epidermis, cornea, and intestinal epithelium.

  • Yugo Takagi, Shun Nishikado, Jumpei Omi, Junken Aoki
    2022 Volume 45 Issue 8 Pages 1008-1021
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Lysophospholipids are phospholipids with only one fatty acid. During the past two decades, it has become apparent that lysophospholipids are not merely degradation products but have various physiological and pathological functions in vivo via G protein-coupled receptor (GPCR)-type receptors. These include lysophosphatidic acid (LPA), sphingosine 1-phosphate (S1P), lysophosphatidylinositol/lysophosphatidylglucose (LPI/LPtdGlc), and lysophosphatidylserine (LysoPS). This review focuses on identifying the functions of the receptors, enzymes, transporters, and carrier proteins required for these four lysophospholipids to function as lipid mediators. We also note that many of advances in this field have been made by Japanese pharmaceutical scientists.

Communication to the Editor
  • Kouya Yamaki, Kiyoe Ohta, Norihiro Kobayashi, Izumi Morita, Yuki Kiguc ...
    2022 Volume 45 Issue 8 Pages 1022-1026
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    The emu is the second largest ratite; thus, their sera and egg yolks, obtained after immunization, could provide therapeutic and diagnostically important immunoglobulins with improved production efficiency. Reliable purification tools are required to establish a pipeline for supplying practical emu-derived antibodies, the majority of which belongs to the immunoglobulin Y (IgY) class. Therefore, we generated a monoclonal secondary antibody specific to emu IgY. Initially, we immunized an emu with bovine serum albumin multiply haptenized with 2,4-dinitrophenyl (DNP) groups. Polyclonal emu anti-DNP antibodies were partially purified using conventional precipitation method and used as antigen for immunizing a BALB/c mouse. Splenocytes were fused with myeloma cells and a hybridoma clone secreting a desirable secondary antibody (mAb#2-16) was established. The secondary antibody bound specifically to emu-derived IgY, distinguishing IgYs from chicken, duck, ostrich, quail, and turkey, as well as human IgGs. Affinity columns immobilizing the mAb#2-16 antibodies enabled purification of emu IgY fractions from sera and egg yolks via simple protocols, with which we succeeded in producing IgYs specific to the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) spike protein with a practical binding ability. We expect that the presented purification method, and the secondary antibody produced in this study, will facilitate the utilization of emus as a novel source of therapeutic and diagnostic antibodies.

Regular Articles
  • Xuejie Zhu, Xiaojie Chen, Guoli Wang, Dan Lei, Xiaoyu Chen, Kehao Lin, ...
    2022 Volume 45 Issue 8 Pages 1027-1035
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    The reactive oxygen species (ROS) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway play critical roles in the pathogenesis of prostate cancer by modulating cell proliferation. Picropodophyllin (PPP), an inhibitor of the insulin-like growth factor 1 receptor (IGF-1R), exerts significant antitumor effects via the PI3K/AKT signaling pathway. However, the effects of PPP on prostate cancer via ROS production and the PI3K/AKT signaling pathway remain elusive. Herein, we focused on examining the antitumor effects of PPP on DU145 and LNCaP human prostate cancer cells to determine the possible molecular mechanism. Our data indicated that the inhibitory effect of PPP on the proliferation of DU145 and LNCaP human prostate cancer cells was mediated by apoptosis induction and cell cycle blockade. Furthermore, PPP significantly influenced the expression of apoptosis-related, cell cycle, ROS production, and PI3K/AKT signaling proteins. These findings suggest that PPP can induce cell cycle arrest and apoptosis via the production of ROS and inhibition of PI3K/AKT signaling pathway, thereby suppressing the proliferation of prostate cancer cells.

  • Kaori Morimoto, Makoto Ishii, Yoshikazu Sugimoto, Takuo Ogihara, Mikio ...
    2022 Volume 45 Issue 8 Pages 1036-1042
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    Dextran is a promising candidate as a nanocarrier of chemotherapeutic drugs due to its biocompatibility, biodegradability, and ability to accumulate in tumors. Furthermore, dextran derivatives interact with P-glycoprotein (P-gp), so we hypothesized that they may be available as tumor-specific drug delivery systems with the ability to reverse multidrug resistance. Here, to test this idea, we investigated whether dextran and its derivatives inhibit breast cancer resistance protein (BCRP), multidrug resistance associated protein 1 (MRP1), and P-gp in vitro. First, we examined their effect on the uptake of specific fluorescent substrates by inside-out Sf-9 membrane vesicles overexpressing BCRP, MRP1, and P-gp. BCRP and MRP1 were significantly inhibited by 2-hydroxypropyl-trimethylammonium-dextran of 4 and 70 kDa (Q-D4 and Q-D70) at a concentration near the clinically used concentration of dextran; however, P-gp was not inhibited. A structure–activity study showed that Q-D4, Q-D70, and 40 kDa diethylaminoethyl-dextran (DEAE-D40) significantly inhibited BCRP, while 4, 40, and 70 kDa dextrans (D4, D40, and D70), dextran sulfate (Sul-D40), and the individual saccharide components of dextran did not. These results suggest that the cationic side chains, but not the saccharides, are important for BCRP inhibition. Finally, cell-based efflux assay was conducted. Q-D4, Q-D70, and DEAE-D40 did not specifically increase the retention of Hoechst33342 in BCRP-overexpressing KB cells. Similarly, Q-D4 and Q-D70 did not affect the intracellular retention of specific fluorescent substrates in MRP1- and P-gp-overexpressing KB cells. The ineffectiveness in cellular systems is presumably due to inability of the dextran derivatives to access transporters located on the cytoplasmic side of the cell membrane.

  • Hongliu Chen, Ying Shen, Yi Liang, Ying Qiu, Meili Xu, Chaoqian Li
    2022 Volume 45 Issue 8 Pages 1043-1052
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    Advance online publication: May 20, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Selexipag, a long-acting and selective prostacyclin (PGI2) IP receptor agonist, has in aged rats with stroke revealed effects of inhibiting inflammation, ameliorating damage to the blood-brain barrier, and alleviating oxidative stress. However, in the case of acute respiratory distress syndrome (ARDS) characterized by diffuse alveolar damage and lung capillary endothelial injury, its effects yet remain unknown. In this study, we investigated effects of the prophylaxis by Selexipag on a mouse model of ARDS established by the lipopolysaccharide (LPS) challenge and potential mechanism. Compared to the LPS-challenged mice, the LPS-challenged mice with the prophylaxis by 0.5 or 1 mg/kg of Selexipag exhibited significantly alleviated lung histological manifestations, reduced protein leakage, decreased levels of interleukin (IL)-1β, IL-6, and monocyte chemotactic protein-1 (MCP-1), diminished expressions of E-selectin and vascular cell adhesion molecule-1 (VCAM-1) mRNA, noticeably increased expressions of zonula occludens-1 (ZO-1) and vascular endothelial cadherin (VE-cadherin) protein, escalated lung cAMP levels, and raised levels of lung relative phosphorylated-protein kinase A catalytic subunit (p-PKA C) at Thr197 and exchange protein activated by cAMP 1 (Epac1) protein. These results suggest that, through suppressing inflammation and reducing vascular endothelial damage, Selexipag can effectively ameliorate the LPS-induced ARDS on mice. The lung cAMP and its downstream signaling modules, PKA and Epac1, possibly constitute the main regulative molecular mechanism. Selexipag appears to hold promise to become a new potential therapeutic option for ARDS.

  • Shohei Nakano, Norihisa Mikami, Mai Miyawaki, Saho Yamasaki, Shoko Miy ...
    2022 Volume 45 Issue 8 Pages 1053-1060
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    Advance online publication: May 24, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Combination treatment using fingolimod (FTY720), an immunomodulator, and a pathogenic antigen prevents the progression of glucose-6-phosphate isomerase (GPI)325-339-induced arthritis. In this study, we focused on myeloid-derived suppressor cells (MDSCs; CD11b+Gr-1+ cells) and investigated the effects of the combination treatment on these cells. DBA/1J mice with GPI325-339-induced arthritis were treated using FTY720 and/or GPI325-339 for five days. The expanded CD11b+Gr-1+ cell population and its inhibitory potential were examined. The percentage of CD369+CD11b+Gr-1+ cells effectively increased in the combination-treated mice. The inhibitory potential of CD369+CD11b+Gr-1+ cells was higher than that of cells not expressing CD369. Among bone marrow cells, the expression of CD369 in CD11b+Gr-1+ cells increased following stimulation with granulocyte-macrophage colony-stimulating factor, and the expression of CD11c increased accordingly. The increased CD11c expression indicated a decrease in the potential to suppress T cell proliferation based on the results of the suppression assay. The percentage of CD11cCD369+ cells in CD11b+Gr-1+ cells that were induced by the combination treatment also increased, and these cells tended to have a higher capacity to inhibit T cell proliferation. In conclusion, the combination treatment using FTY720 and the pathogenic antigen effectively induces MDSC, which demonstrates a high potential for suppressing T cell proliferation in the lymph nodes, thereby establishing an immune-tolerant state.

  • Wei Zhang, Chao Liu, Mengmeng Wang, Zhizhou Yang, Jian Yang, Yi Ren, L ...
    2022 Volume 45 Issue 8 Pages 1061-1068
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    Advance online publication: May 31, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    Macrophages are a key in innate immune responses and play vital roles in homeostasis and inflammatory diseases. Phosphatidylserine-specific phospholipase A1 (PS-PLA1) is a specific phospholipase which hydrolyzes fatty acid from the sn-1 position of phosphatidylserine (PS) to produce lysophosphatidylserine (lysoPS). Both PS and lysoPS are associated with activation of immune cells including macrophages. However, the effect of PS-PLA1 on macrophage inflammation remains unclear. The purpose of this study is to evaluate the role of PS-PLA1 in lipopolysaccharide (LPS)-induced macrophage inflammation. Alterations of PS-PLA1 expression in LPS-stimulated RAW264.7 macrophages were investigated via Western blot. PS-PLA1 stable knockdown and overexpression RAW264.7 cell lines were generated by infecting cells with appropriate lentiviral vectors, respectively. PS-PLA1 expression was found to be dramatically upregulated in RAW264.7 macrophages after LPS stimulation. PS-PLA1 knockdown promotes while PS-PLA1 overexpression ameliorates the release of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and nitric oxide from RAW264.7 cells and M1 macrophage polarization. Additionally, PS-PLA1 knockdown facilitates phosphorylation of p38, extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), while PS-PLA1 overexpression attenuates their phosphorylation. Moreover, mitogen-activated protein kinase (MAPK) inhibitors block the release of TNF-α and IL-1β in PS-PLA1 knockdown RAW264.7 cells after LPS stimulation. These findings suggest PS-PLA1 ameliorates LPS-induced macrophage inflammation by inhibiting MAPKs activation, and PS-PLA1 might be considered as a target for modulating macrophage inflammation.

  • Masashi Kawami, Mikito Honda, Takuya Hara, Ryoko Yumoto, Mikihisa Taka ...
    2022 Volume 45 Issue 8 Pages 1069-1076
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    Methotrexate (MTX) is known to induce serious lung diseases, such as pulmonary fibrosis. Although we demonstrated that MTX is associated with epithelial–mesenchymal transition (EMT), the underlying mechanism remains unclear. Nuclear factor erythroid 2-related factor 2 (Nrf2), an oxidative stress response regulator, is related to EMT induction. In the present study, we examined the association of Nrf2 with the MTX-induced EMT in the alveolar epithelial cell line A549. MTX treatment decreased the mRNA expression of heme oxidase-1 (HO-1), a target of Nrf2, which was inhibited by co-treatment with diethyl maleate (DEM), an Nrf2 activator. Additionally, the MTX-induced increase in reactive oxygen species (ROS) production was significantly suppressed by DEM. Furthermore, DEM decreased mRNA/protein expression levels of α-smooth muscle actin (SMA), a representative EMT marker, which were upregulated by MTX. Nuclear expression and localization of Nrf2 were suppressed by MTX treatment, which led to a decrease in Nrf2 activity. Finally, in Nrf2 knockdown cells, the MTX-induced enhancement of α-SMA mRNA/protein expression was not observed, indicating that downregulation of Nrf2 may play a critical role in the MTX-induced EMT in A549 cells. These results suggest that Nrf2-regulated transcriptional activity would be associated with the MTX-induced EMT induction.

  • Yukari Katsuhara, Shunya Ikeda
    2022 Volume 45 Issue 8 Pages 1077-1083
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    The results of previous studies that have used databases to investigate the associations between sodium-glucose-cotransporter-2 (SGLT-2) inhibitors and acute renal failure (ARF) have differed, and the impact of biases such as the Weber effect and stimulated reporting has not been fully examined. This study aimed to determine the associations between SGLT-2 inhibitors and ARF using signal detection, the effects on signals of regulatory agency alerts for ARF, and the publication of prominent studies by measuring changes in signals over time. Data registered in the Food and Drug Administration’s Adverse Event Reporting System from January 2013 to March 2020 were downloaded, signals were detected, and reporting odds ratios (RORs) were calculated for each country of occurrence (Japan/the United States). Quarterly changes in the number of reports and RORs were examined. Although an association between SGLT-2 inhibitor use and ARF was suggested in the United States, this study did not suggest such an association in Japan. The number of reports and RORs fluctuated when regulatory alerts and prominent studies were published, and events affecting the number of reports and RORs varied by country. This study revealed the difference in the associations between SGLT-2i and ARF in Japan and the United States. Additionally, the signal was identified to be influenced by alerts and the publication of studies. Therefore, these results should be interpreted cautiously as there could be a possibility of overestimation due to alert biases and publication of studies.

  • Yu Maeda, Ryota Tanaka, Ryosuke Tatsuta, Kuniko Takano, Takehiro Hashi ...
    2022 Volume 45 Issue 8 Pages 1084-1090
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    The pharmacokinetics of voriconazole shows large intra-individual and inter-individual variability and is affected by various factors. Recently, inflammation has been focused as a significant factor affecting the variability. This study aimed to compare the influence of C-reactive protein (CRP) and other clinical laboratory parameters on intra-individual variability in trough voriconazole concentration and examine the impact of inflammation in patients with hematological malignancies. We conducted a retrospective, single-center, observational cohort study. Forty-two patients with hematological malignancy who received oral voriconazole for prophylaxis against deep mycosis and underwent multiple measurements of trough plasma voriconazole concentration were recruited. Quantitative changes in pharmacological and clinical laboratory parameters (Δ) were calculated as the difference between the current and preceding measurements. Voriconazole concentration/maintenance dose per weight (C/D) was found to correlate positively with CRP level (n = 202, rs = 0.314, p < 0.001). Furthermore, ΔC/D correlated positively with ΔCRP level (n = 160, rs = 0.442, p < 0.001), and ΔCRP showed the highest correlation coefficient among the laboratory parameters. Univariate and multivariate analyses identified ΔCRP (p < 0.001) and Δgamma-glutamyl transpeptidase (γGTP) (p = 0.019) as independent factors associated with ΔC/D. Partial R2 were 0.315 for ΔCRP and 0.024 for ΔγGTP, suggesting markedly greater contribution of ΔCRP to ΔC/D. In conclusion, since clinical laboratory parameters other than CRP had little influence on trough plasma voriconazole concentration, therapeutic drug monitoring and dose adjustment considering fluctuation in CRP level would be important for proper use of voriconazole in patients with hematological malignancies.

  • Shu Sekiya, Tatsunori Suzuki, Rei Tanaka, Shumpei Harigai, Konosuke Sh ...
    2022 Volume 45 Issue 8 Pages 1091-1100
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    In Japan, the Pharmaceutical and Medical Device Act was amended in December 2019 and now requires pharmacists to follow-up patients continuously during treatment to ensure proper use of medicines. According to some reports on patients with type 2 diabetes mellitus (T2DM), follow-up by doctors is effective for improving treatment. Enhanced face-to-face medication counseling by pharmacists leads to good glycemic control in patients with diabetes. However, the effects of information and communication technology (ICT)-based follow-up during the medication period are not well-understood. We determined the efficacy of pharmacists’ follow-up using FollowNavi, a patient compliance instruction support system, and using our developed LINE tool for patients with T2DM. Through a before-after study, changes in glycemic control and medication adherence after 6 months of follow-up were investigated, and multiple regression analysis was performed to investigate the factors associated with changes in hemoglobin A1c (HbA1c) levels. Questionnaire surveys related to usability were completed by patients and pharmacists. In the 35 patients with T2DM, HbA1c levels decreased significantly after 6 months, although fasting blood glucose levels and medication adherence showed no significant differences. Changes in HbA1c levels were significantly associated with age (p = 0.044), baseline HbA1c levels (p < 0.001), and diabetes duration (p = 0.004). In the questionnaire, 81.8% of patients responded that they would prefer to continue using FollowNavi. These results suggest that follow-up using FollowNavi is useful for glycemic control in patients with T2DM.

  • Jose Carlos S. Tayag, Takeo Ishii, Shun Kokuba, Tetsuo Hirata, Hideo S ...
    2022 Volume 45 Issue 8 Pages 1101-1105
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    Drug–drug interactions (DDIs) between warfarin (WF) and fluoropyrimidines are well known. Co-administration of WF and 5-fluorouracil (5-FU) leads to elevations in prothrombin time international normalised ratio (PT-INR). The inhibition of drug metabolism through suppression of CYP activity is a possible cause of prolonged PT-INR elevations. 5-FU and its metabolites are suspected to inhibit CYPs, but the precise mechanisms of action remain unknown. This study aimed to investigate the possible DDI effects of the co-administration of 5-FU with WF using PT-INR and PT-INR/dose ratio as pharmacodynamic parameters. Retrospective case series data were collected from patients who received parenteral 5-FU chemotherapy from April 2009 to December 2019 at the University of the Ryukyus Hospital. Seven patients who received 5-FU in combination with WF were analysed. There was a significant increase in PT-INR and PT-INR/dose during the co-administration of WF and 5-FU (p = 0.0018 and p = 0.0187, respectively; paired t-test). The findings demonstrated significant DDI between 5-FU and WF evident as elevated PT-INR and PT-INR/dose ratio.

  • Linghui Zou, Wenya Ding, Qiuyan Huang, Xu Yang, Jilang Li, Tianyan Hua ...
    2022 Volume 45 Issue 8 Pages 1106-1115
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    Advance online publication: May 20, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Andrographolide (AG), a natural product with various pharmacological effects, exhibited low oral bioavailability owing to its poor solubility, stability, and low absorption. Previous studies have suggested that phospholipid (PC) and hydroxypropyl-β-cyclodextrin (HPCD) could improve the drug solubility and absorption. Moreover, nanoemulsion (NE) has been confirmed as an appropriate enhancer for oral bioavailability. Therefore, AG/HPCD/PC complex (AHPC) was synthesized, and AHPC-loaded nanoemulsion (AHPC-NE) was optimized and prepared using central composite design combined response surface methodology. The average droplet size and polydispersity index (PDI) were 116.50 ± 5.99 and 0.29 ± 0.03 nm, respectively. AHPC-NE with a loading capacity of 0.32 ± 0.01% and an encapsulation efficiency of 96.43 ± 2.27% appeared round and uniformly dispersed based on transmission electron microscopy. In vivo release studies demonstrated that AHPC-NE had good sustained-release effects. Further, AHPC-NE significantly enhanced the absorption of AG with a relative bioavailability of 550.71% compared to AG suspension. Such findings reveal AHPC-NE as a potential strategy for sustained-release and oral bioavailability enhancement.

  • Nobumitsu Hanioka, Toshiko Tanaka-Kagawa, Yoko Mori, Shinichi Ikushiro ...
    2022 Volume 45 Issue 8 Pages 1116-1123
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Flavones, which are distributed in a variety of plants and foods in nature, possess significant biological activities, including antitumor and anti-inflammatory effects, and are metabolized into glucuronides by uridine 5′-diphosphate (UDP)-glucuronosyltransferase (UGT) enzymes in humans. In this study, apigenin, acacetin, and genkwanin, flavones having hydroxyl groups at C5, C7, and/or C4′positions were focused on, and the regioselective glucuronidation in human liver and intestinal microsomes was examined. Two glucuronides (namely, AP-7G and AP-4′G for apigenin, AC-5G and AC-7G for acacetin, and GE-5G and GE-4′G for genkwanin) were formed from each flavone by liver and intestinal microsomes, except for only GE-4′G formation from genkwanin by intestinal microsomes. The order of total glucuronidation activities was liver microsomes > intestinal microsomes for apigenin and acacetin, and liver microsomes < intestinal microsomes for genkwanin. The order of CLint values (x-intercept) based on v versus V/[S] plots for apigenin glucuronidation was AP-7G > AP-4′G in liver microsomes and AP-7G < AP-4′G in intestinal microsomes. The order of CLint values was AC-5G < AC-7G for acacetin and GE-5G < GE-4′G genkwanin glucuronidation in both liver and intestinal microsomes. This suggests that the abilities and roles of UGT enzymes in the glucuronidation of apigenin, acacetin, and genkwanin in humans differ depending on the chemical structure of flavones.

  • Kaito Takayama, Shota Tobori, Chihiro Andoh, Masashi Kakae, Masako Hag ...
    2022 Volume 45 Issue 8 Pages 1124-1132
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by core symptoms, including impairments in social behavior and repetitive interests. Recent studies have revealed that individuals with ASD also display decreased empathy, ultimately leading to difficulties in social relationships; however, another report indicated that individuals with ASD have enhanced emotional empathy. Nonetheless, the neurobiological mechanisms underlying altered empathy in individuals with ASD remain unclear. In this study, we assessed empathy-like behaviors in valproic acid (VPA)-treated mice—a mouse model of ASD with observational fear learning. We then investigated the brain regions and signaling systems responsible for the altered empathy-like behaviors in VPA-treated mice. As a result, mice prenatally exposed to VPA displayed increased empathy-like behaviors, which were not attributed to altered sensitivity to auditory stimuli or enhanced memory for pain-related contexts. Immunohistochemical analysis revealed that the number of c-Fos positive oxytocinergic neurons in the paraventricular nucleus of the hypothalamus (PVN) was significantly higher in VPA-treated mice after observational fear learning. Finally, we found that pretreatment with L-368899, an antagonist of the oxytocin receptor, repressed the empathetic behavior in VPA-treated mice. These results suggest that VPA-treated ASD model animals showed increased emotional empathy-like behaviors through the hyperactivation of PVN oxytocinergic neurons for the first time. Further investigation of this hyperactivity will help to identify extrinsic stimuli and the condition which are capable of activation of PVN oxytocinergic neurons and to identify novel approach to enhance oxytocin signaling, which ultimately pave the way to development of novel therapy for ASD.

    Editor's pick

    ASD are neurodevelopmental disorders characterized by impairments in social behavior and repetitive interests. Individuals with ASD often also display decreased empathy, while recent report indicates that individuals with ASD show enhanced emotional empathy than typically developed individuals. In this study, Takayama et al. assessed socially transmitted fear in observational fear learning paradigm as a proxy of emotional empathy in VPA-treated mice, ASD model mice. The authors found that hyperactivity of oxytocin neurons in the paraventricular nucleus of hypothalamus in VPA-treated mice enhanced empathy-like behaviors in observational fear learning paradigm.

  • Sayaka Kubota, Yuki Yamamoto, Koji Kimura
    2022 Volume 45 Issue 8 Pages 1133-1141
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    Early embryo and sperm transport through the oviductal isthmus depends on the contraction and relaxation of the smooth muscle layers. Dysfunction of the oviduct transport is considered to be one of the causes of infertility. For human infertility, Chinese medicine is used in East Asia. Although there are many clinical reports regarding Tokishakuyakusan (TSS), there is little scientific evidence that it affects infertility. In this study, we investigated the effect of TSS on bovine oviductal contraction and relaxation via the G protein-coupled estrogen receptor 1 (GPER1). We collected bovine oviductal isthmic tissues at four stages of the estrous cycle, classified based on a macroscopic observation of the ovary. The Magnus method was used to monitor longitudinal contractility (frequency, contraction force, and tonus). The effects of TSS solution, GPER1 agonist (G-1), and antagonist (G-15) on oviductal contractility were examined. The protein expression level of GPER1 in the oviductal isthmic smooth muscle of each estrous stage was assessed by Western blotting. Although TSS did not affect frequency and contraction force, the tonus was significantly increased by TSS or G-1 at all stages (p < 0.05), and the effect was especially highest at days 1–4 after ovulation. The addition of G-15 significantly suppressed the TSS-induced increase of oviductal tonus at all stages (p < 0.05). There was no significant difference in GPER1 protein expression among the estrous stages. TSS affects oviductal contractility by increasing tonus via GPER1, and it may accelerate gamete and early embryo transport by contracting the oviducts longitudinally.

  • Makiko Shimizu, Riku Hayasaka, Yusuke Kamiya, Hiroshi Yamazaki
    2022 Volume 45 Issue 8 Pages 1142-1157
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    Advance online publication: May 27, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    A system for predicting apparent bidirectional permeability (Papp) across Caco-2 cells of diverse chemicals has been reported. The present study aimed to investigate the relationship between in silico-generated Papp (from apical to basal side, Papp A to B) for 301 substances with diverse structures and a binary classification of the reported roles of efflux P-glycoprotein or breast cancer resistant protein. The in silico log(Papp A to B/Papp B to A) values of 70 substances with reported active efflux and 231 substances with no reported active efflux were significantly different (p < 0.01). The probabilities of active efflux transport estimated by trivariate analysis with log MW, log DpH 6.0, and log DpH 7.4 for the 70 active-efflux-positive compounds were higher than those of the other 231 substances (p < 0.01); the area under the corresponding receiver operating characteristic (ROC) curve was 0.81. Further probability values estimated using a machine learning algorithm with 30 chemical descriptors as inputs yielded an area under the ROC curve of 0.79. Using a secondary set of 52 efflux-positive and 48 efflux-negative medicines, the final trivariate-generated probabilities resulted in no significant differences between these binary groups (p = 0.09); however, the final machine learning model demonstrated a good area under the ROC curve of 0.79. Consequently, a combination of the previously established system for generating the permeability coefficients across intestinal monolayers (a continuous variable) and the currently proposed system for predicting the roles of additional active efflux (a binary classification) could prove useful; high accuracy was achieved by applying machine learning using in silico-generated chemical descriptors.

  • Keisuke Obara, Rikako Inaba, Mirai Kawakita, Azusa Murata, Kento Yoshi ...
    2022 Volume 45 Issue 8 Pages 1158-1165
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    Administration of a P2X4 receptor antagonist to asthma model mice improved asthma symptoms, suggesting that P2X4 receptor antagonists may be new therapeutics for asthma. However, the effects of these antagonists on tracheal/bronchial smooth muscle (TSM and BSM) have not been investigated. This study examined the effects of NP-1815-PX, a selective P2X4 receptor antagonist, on guinea pig TSM and BSM contractions. In epithelium-intact TSM, NP-1815-PX (10−5 M) strongly suppressed ATP-induced contractions. ATP-induced contractions were strongly suppressed by indomethacin (3 × 10−6 M) and ONO-8130 (a prostanoid EP1 receptor antagonist, 10−7 M). ATP-induced contractions were partially suppressed by SQ 29,548 (a prostanoid TP receptor antagonist, 3 × 10−7 M), although the difference was not significant. In contrast, ATP-induced contractions were not affected by AL 8810 (a prostanoid FP receptor antagonist, 10−5 M) or L-798,106 (a prostanoid EP3 receptor antagonist, 10−8 M). NP-1815-PX (10−5–10−4 M) strongly suppressed U46619 (a TP receptor agonist)- and prostaglandin F (PGF)-induced epithelium-denuded TSM and BSM contractions, which were largely inhibited by SQ 29,548. Additionally, NP-1815-PX (10−5–10−4 M) strongly suppressed the U46619-induced increase in intracellular Ca2+ concentrations in human TP receptor-expressing cells. However, NP-1815-PX (10−4 M) did not substantially inhibit the TSM/BSM contractions induced by carbachol, histamine, neurokinin A, or 50 mM KCl. These findings indicate that NP-1815-PX inhibits guinea pig TSM and BSM contractions mediated through the TP receptor, in addition to the P2X4 receptor, whose stimulation mainly induces EP1 receptor-related mechanisms. Thus, these findings support the usefulness of NP-1815-PX as a therapeutic drug for asthma.

    Editor's pick

    Possible usefulness of P2X4 receptor (P2X4-R) antagonists as new therapeutics for asthma has been proposed based on the results using asthma model mice. However, the effects P2X4-R antagonists on the contractions of tracheal/bronchial smooth muscle (TSM/BSM) have not been investigated. To elucidate this issue, the authors evaluated the effects of a P2X4-R antagonist NP-1815-PX on the contractions of guinea pig TSM/BSM. NP-1815-PX strongly suppressed ATP-induced, epithelium-dependent TSM contractions and prostanoid TP receptor-mediated, epithelium-independent TSM/BSM contractions. These findings indicate that NP-1815-PX inhibits TSM/BSM contractions mediated through TP as well as P2X4 receptors, and NP-1815-PX is a potential therapeutic drug for asthma.

  • Masakazu Hatano, Tomohiro Mizuno, Yuki Arakawa, Risa Inagaki, Arisa Ka ...
    2022 Volume 45 Issue 8 Pages 1166-1171
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Polypharmacy in older adults causes problems such as increased adverse drug reactions, overdose or duplication, and poor medication adherence. We have established a “medication review team” organized by pharmacists. This prospective and retrospective observational study evaluated the effectiveness of the pharmacist-led team-based approach for reducing polypharmacy as compared to the individual pharmacist approach. Data on the individual pharmacist approach were collected retrospectively, but prospectively for the pharmacist-led team approach. The study included patients who were admitted to the nephrology, orthopedic surgery, and psychiatry wards. Characteristics for patient included in each study group were adjusted using the propensity score method. The pharmacist-led team approach had a significantly higher medication change rate compared to that of the individual pharmacist approach (odds ratio (OR), 2.28; 95% confidence interval (CI), 1.21 to 4.46; p = 0.009). The rate of patients with two or more medication discontinuations and the rate of patients with intervention by young clinical pharmacist were also significantly higher in the pharmacist-led team approach (OR, 2.19; 95% CI, 1.06 to 4.74; p = 0.03 and OR, 5.67; 95% CI, 1.22 to 53.15; p = 0.02, respectively). The rate of patients with discontinuation of potentially inappropriate medications was not significantly different between the two groups (OR, 2.07; 95% CI, 0.86 to 5.33; p = 0.11). Our results suggest that it is possible to improve the quality of medication review by conducting team conferences even with only pharmacists.

  • Yoshiaki Yamaguchi, Iori Murai, Momoko Takeda, Shotaro Doi, Takehito S ...
    2022 Volume 45 Issue 8 Pages 1172-1179
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    The suprachiasmatic nucleus (SCN) is the master circadian clock in mammals and is properly entrained by environmental light cycle. However, the molecular mechanism(s) determining the magnitude of phase shift by light is still not fully understood. The orphan G-protein-coupled receptor Gpr176 is enriched in the SCN, controls the pace (period) of the circadian rhythm in behavior but is not apparently involved in the light entrainment; Gpr176−/− animals display a shortened circadian period in constant darkness but their phase-resetting responses to light are normal. Here, we performed microarray analysis and identified enhanced mRNA expression of neuromedin U (Nmu) and neuromedin S (Nms) in the SCN of Gpr176−/− mice. By generating C57BL/6J-backcrossed Nmu/Nms/Gpr176 triple knockout mice, we noted that the mutant mice had a greater magnitude of phase shift in response to early subjective night light than wildtype mice, while Nmu/Nms double knockout mice as well as Gpr176 knockout mice are normal in the phase shifts induced by light. At the molecular level, Nmu−/−Nms−/−Gpr176−/− mice had a reduced induction of Per1 and cFos mRNA expression in the SCN by light and mildly upregulated circadian expression of Per2, Prok2, Rgs16, and Rasl11b. These expressional changes may underlie the phenotype of the Nmu/Nms/Gpr176 knockout mice. Our data argue that there is a mechanism requiring Nmu, Nms, and Gpr176 for the proper modulation of light-induced phase shift in mice. Simultaneous modulation of Nmu/Nms/Gpr176 may provide a potential target option for modulating the circadian clock.

    Editor's pick

    Circadian clock disruption has been linked to diseases ranging from metabolic syndrome to cancer. Therefore, the circadian system has become an attractive target for research and clinical care innovations. The authors show that the orphan G-protein-coupled receptor Gpr176 is involved in light entrainment of the circadian clock through a mechanism requiring two related neuropeptides, neuromedin U and neuromedin S. It is suggested by the authors that simultaneous modulation of these neuropeptides and Gpr176 may constitute a potential therapeutic option for modulating the circadian clock.

  • Naoko Kadota, Akari Yoshida, Atsushi Sawamoto, Satoshi Okuyama, Mitsun ...
    2022 Volume 45 Issue 8 Pages 1180-1184
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    In Japan, ibudilast (IBD) is a therapeutic agent used to treat asthma, allergic conjunctivitis, and dizziness caused by cerebrovascular disease. Previously, we have reported that IBD could reduce the secretion of proinflammatory cytokines, including interleukin (IL)-6 and tumor necrosis factor (TNF)-α, in lipopolysaccharide (LPS)-treated RAW264.7 monocyte-linage cells in vitro. In the present study, we examined the anti-inflammatory effects of IBD in vivo. As IL-6 is a biomarker for sepsis and has been suggested to exacerbate symptoms, we determined whether IBD reduces IL-6 levels in vivo and improves sepsis symptoms in animal models. We observed that IBD treatment reduced IL-6 levels in the lungs of LPS-treated mice and improved LPS-induced hypothermia, one of the symptoms of sepsis. In addition, IBD reduced IL-6 and attenuated plasminogen activator inhibitor-1 (PAI-1) and alanine aminotransferase (ALT) levels in the serum of LPS-treated mice. Elevated PAI-1 levels exacerbate sepsis-induced disseminated intravascular coagulation (DIC), and ALT is a biomarker for liver dysfunction. IBD improved the survival of mice administered a lethal dose of LPS. IBD administration ameliorated kidney pathology of model mice. Overall, these results suggest that IBD exerts anti-inflammatory functions in vivo and could be a drug candidate for treating endotoxemia, including sepsis.

  • Yoko Mori, Akira Aoki, Yoshinori Okamoto, Takashi Isobe, Susumu Ohkawa ...
    2022 Volume 45 Issue 8 Pages 1185-1190
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    Bitter taste receptors (TAS2Rs) are expressed by oral cavity cells in mammals and classically function as sensors for bitter compounds. There are 25 functional isoforms of human TAS2Rs, with individual bitter ligands. Each human TAS2R isoform is distributed in several tissues, such as the airway epithelia and gastrointestinal tract, and plays an important role in physiological functions. However, quantification of each isoform is difficult because of highly homologous sequences between some TAS2R isoforms. Therefore, differentiating the isoforms by their expression levels is suitable for clarifying the tissue-specific effects of bitter compounds. In this study, we developed a real-time quantitative PCR (qPCR) method to determine the expression of each TAS2R isoform. Using plasmid standards harboring each isoform, we confirmed that the current assay can quantify the gene expression of each isoform, with negligible interference from other isoforms. In addition, our methods can successfully discriminate between the mRNA expression of each isoform in human cell lines and tissues. Therefore, this qPCR method can successfully quantify the mRNA level of each TAS2R isoform. This method will contribute to a better understanding of the molecular mechanisms underlying the TAS2R ligand-activated signal transduction.

  • Misa Muraoka, Moeka Ohno, Takuya Nakai, Hideyuki Matsuura, Kazuya Naga ...
    2022 Volume 45 Issue 8 Pages 1191-1197
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Gamma-glutamylcysteine (γ-EC) is an intermediate generated in the de novo synthesis of glutathione (GSH). Recent studies have revealed that the administration of γ-EC shows neuroprotective effects against oxidative stress in age-related disorders and chronic diseases like Alzhiemer’s disease in model animals, which is not expected function in GSH. A phytochelatin synthase-like enzyme derived from Nostoc sp. (NsPCS) mediates γ-EC synthesis from GSH. To achieve low-cost and stable commercial level supply, the availability of immobilized NsPCS for γ-EC production was investigated in this study. Among the tested immobilization techniques, covalent binding to the cellulose carrier was most effective, and could convert GSH completely to γ-EC without decreasing the yield. The stable conversion of γ-EC from 100 mM GSH was achieved by both batch repeated and continuous reactions using the immobilized NsPCS on cellulose sheet and column shape monolith, respectively. The immobilization of NsPCS on those carriers is promising alternative technique for high-yielding and cost-effective production of γ-EC on its commercial applications.

Notes
  • Chihiro Udagawa, Sherwin Kuah, Tatsunori Shimoi, Ken Kato, Teruhiko Yo ...
    2022 Volume 45 Issue 8 Pages 1198-1202
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML
    Supplementary material

    Trastuzumab (herceptin) is an effective drug for human epidermal growth factor receptor type 2 (HER2)-positive cancer. However, cardiotoxicity remains a serious complication. In our previous genome-wide association study (GWAS), we identified potential associations for five single nucleotide polymorphisms (SNPs) with trastuzumab-induced cardiotoxicity in a Japanese population. To validate this association, here we performed replication studies using Japanese and Singaporean case-control cohorts (Japan: 6 cases and 206 controls; Singapore: 22 cases and 178 controls). Although none of the SNPs showed a statistically significant association with trastuzumab-induced cardiotoxicity, we show that three (rs8032978, rs7406710 and rs9316695) and four (rs8032978, rs7406710, rs28415722 and rs11932853) SNPs had an effect in the same direction in the Japanese and the Singaporean cohort, respectively, as that in our previous study. Combining the previous study with the current replication studies, we find a strong association for two SNPs, rs8032978 and rs7406710, with trastuzumab-induced cardiotoxicity (Pcombined = 4.92 × 10−5 and 5.50 × 10−5, respectively). These data suggest that rs8032978 and rs7406710 could be predictive markers of trastuzumab-induced cardiotoxicity in Japanese and Singaporean populations, and support their potential use in clinical risk assessment. These findings offer a first step toward the development of clinically available markers for the potential risk of trastuzumab-induced cardiotoxicity as well as an improved understanding of the pathogenesis of this complication.

  • Osamu Nakagawasai, Akihiro Ambo, Kohei Takahashi, Hiroshi Onogi, Yuki ...
    2022 Volume 45 Issue 8 Pages 1203-1207
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    The opioid system in the central nervous system regulates depressive-like behavior in animals. Opioid receptors and their endogenous ligands have been focused on as novel therapeutic targets for depression. We synthesized dermorphin (DRM)-dynorphin (DYN) analogs (DRM-DYN001–004) using the message-address concept concerning interactions with opioid receptors. It has previously been reported that DRM-DYN001, 003, and 004 have shown high affinities for μ- and κ-opioid receptors, whereas all analogs had a lower affinity for the δ-opioid receptor than for other receptors using a receptor binding assay. However, it remains unknown whether these analogs show antidepressant-like effects in mice. We examined the effects of DRM-DYN analogs on the duration of immobile behavior in a tail suspension test. Intracerebroventricular administration of DRM-DYN001 in mice shortened the duration of immobile behavior, but did not affect locomotion. The DRM-DYN001-induced antidepressant-like effect was inhibited by co-administration of naloxone (non-selective opioid receptor antagonist), naloxonazine (selective μ1-opioid receptor antagonist), or nor-BNI (κ-opioid receptor antagonist), but not naltrindole (δ-opioid receptor antagonist). These data suggest that DRM-DYN001 exerts an antidepressant-like effect via activation of the central μ1- and κ-opioid receptors in mice and may represent a new lead peptide for further investigation for the development of novel therapeutic approaches for depression.

  • Hiroyasu Sakai, Ken Sato, Koya Ito, Ikoi Kosugi, Miho Kiyama, Risako K ...
    2022 Volume 45 Issue 8 Pages 1208-1212
    Published: August 01, 2022
    Released on J-STAGE: August 01, 2022
    JOURNAL FREE ACCESS FULL-TEXT HTML

    We have previously reported that swellings caused by haptens, such as 2,4,6-trinitrochlorobenzene (TNCB), may be associated with the extracellular signal-regulated kinase (ERK)-induced proliferation pathway. However, the involvement of the Spred/Sprouty family as critical negative regulators of the Ras/Raf/ERK signaling pathway at disease sites is not well-established. Thus, in the present study, the effects of hapten-challenge on the expression levels of genes and proteins associated with the Spred/Sprouty family in the ear of mice were investigated. The activation of ERK and epidermal growth factor receptor (EGFR) tyrosine kinase was inhibited by their selective inhibitors, namely, U0126 and PD168393, respectively. Twenty-four hours after the final challenge by the haptens TNCB, 2,4-dinitrofluorobenzene, or oxazolone, ear thickness was augmented by challenge with all haptens and the gene expression levels of Spred1, Spred2, Sprouty1, and Sprouty2 in swelling induced by all haptens were significantly decreased. Furthermore, Spred2, Sprouty1, and Sprouty2 genes were decreased in the epidermis and dermis of the TNCB-challenged ear. In conclusion, it is possible that the mechanism of hapten-challenge-induced skin thickening involves not only the enhancement of cell proliferative functions via the activation of ERK by EGFR tyrosine kinase activation but also the decreases expression of Spred/Sprouty family members.

feedback
Top