16 results on '"Okuno, Takayuki"'
Search Results
2. An anatomical review of various superior mesenteric artery-first approaches during pancreatoduodenectomy for pancreatic cancer.
- Author
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Yamamoto J, Kudo H, Kyoden Y, Ajiro Y, Hiyoshi M, Okuno T, Kawasaki H, Nemoto M, and Yoshimi F
- Subjects
- Humans, Neoplasm Invasiveness, Pancreatic Neoplasms blood supply, Mesenteric Artery, Superior anatomy & histology, Pancreatic Neoplasms pathology, Pancreatic Neoplasms surgery, Pancreaticoduodenectomy methods, Vascular Neoplasms blood supply, Vascular Neoplasms pathology
- Abstract
When pancreatic head cancer invades the superior mesenteric artery (SMA), attempts at curative resection are aborted. Preoperative imaging diagnostics to determine the surgical curability have yet to surpass the intraoperative information acquired via inspection, palpation, and trial dissection. Pancreatoduodenectomy (PD) is a standard measure for treating periampullary cancers. In conventional PD, SMA invasion is usually identified by dissecting the retroportal lamina, which connects the uncinate process and SMA nerve plexus after dividing the neck of the pancreas. During PD for pancreatic head cancer, this retroperitoneal margin frequently vitiates surgical curability. SMA-first approaches during PD are methods where the SMA is dissected first by severing the posterior pancreatic capsule to assess the SMA involvement of pancreatic cancer early in the operation. The first report of such an approach prompted subsequent reports of various maneuvers that are now known collectively as "artery-first" approaches. We herein review those approaches by classifying them according to (1) the side of the mesocolon from where the SMA approach occurs (supracolic or infracolic) and (2) the direction of access (right or left and anterior or posterior). The steps of the reported PD procedures are numbered according to a timeline and summarized using anatomical division of the SMA.
- Published
- 2021
- Full Text
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3. Discovery of a benzimidazole series as the first highly potent and selective ACSL1 inhibitors.
- Author
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Hayashi K, Kondo N, Omori N, Yoshimoto R, Hato M, Shigaki S, Nagasawa A, Ito M, and Okuno T
- Subjects
- Animals, Benzimidazoles chemical synthesis, Benzimidazoles chemistry, Coenzyme A Ligases metabolism, Dose-Response Relationship, Drug, Enzyme Inhibitors chemical synthesis, Enzyme Inhibitors chemistry, Humans, Mice, Mice, Knockout, Molecular Structure, Structure-Activity Relationship, Benzimidazoles pharmacology, Coenzyme A Ligases antagonists & inhibitors, Drug Discovery, Enzyme Inhibitors pharmacology
- Abstract
Long-chain acyl-CoA synthetase-1 (ACSL1), an enzyme that catalyzes the synthesis of long-chain acyl-CoA from the corresponding fatty acids, is believed to play essential roles in lipid metabolism. Structure activity relationship studies based on HTS hit compound 1 delivered the benzimidazole series as the first selective and highly potent ACSL1 inhibitors. Representative compound 13 exhibited not only remarkable inhibitory activity against ACSL1 (IC
50 = 0.042 μM) but also excellent selectivity for the other ACSL isoforms. In addition, compound 13 demonstrated an in vivo suppression effect against the production of long-chain acyl-CoAs in mouse., (Copyright © 2020 Elsevier Ltd. All rights reserved.)- Published
- 2021
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4. Filiform polyposis with sigmoid colon adenocarcinoma: a case report.
- Author
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Okuno T, Kanazawa T, Kishi H, Anzai H, Yasuda K, and Ishihara S
- Abstract
Background: Filiform polyposis is a rare form of inflammatory polyposis, which is occasionally formed in the colon of patients with history of inflammatory bowel disease (IBD). It is characterized by presence of several to hundreds of slender, worm-like polyps in the colon lined by histologically normal colonic mucosa and often coalesce, resulting in a tumor-like mass. Filiform polyposis is most frequently associated with a post-inflammatory reparative process in patients with IBD history, and only cases of filiform polyposis occurring in patients without IBD history have been reported. Filiform polyposis has been considered as a benign inflammatory polyposis without any risk of dysplasia, while the possibility of carcinogenesis of inflammatory polyps is not fully excluded. To date, only three cases of filiform polyposis coexisting with dysplasia have been reported., Case Presentation: A 59-year-old male patient with no past medical history of IBD underwent laparoscopic sigmoidectomy for obstructive filiform polyposis, which was associated with sigmoid colon adenocarcinoma. Based on the histological findings of the resected specimen, invasive sigmoid colon adenocarcinoma was surrounded by filiform polyposis, and adenocarcinoma also scattered uniformly on the surface of filiform polyposis. In immunohistochemistry, abnormal p53 expression was observed in adenocarcinoma, while it was not shown in mucosa on filiform polyposis., Conclusions: This is the fourth case of filiform polyposis that is closely associated with colon dysplasia or adenocarcinoma based on histological findings. However, immunohistochemical findings did not support the theory that inflammation initiates adenocarcinoma in filiform polyposis like IBD. Hence, further immunohistochemical and genetic analyses are needed to clarify the association between filiform polyposis and carcinogenesis.
- Published
- 2019
- Full Text
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5. A novel RORγt inhibitor is a potential therapeutic agent for the topical treatment of psoriasis with low risk of thymic aberrations.
- Author
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Imura C, Ueyama A, Sasaki Y, Shimizu M, Furue Y, Tai N, Tsujii K, Katayama K, Okuno T, Shichijo M, Yasui K, and Yamamoto M
- Subjects
- Administration, Cutaneous, Animals, Cells, Cultured, Dermatologic Agents therapeutic use, Disease Models, Animal, Drug Evaluation, Preclinical, Healthy Volunteers, Humans, Immunity, Innate drug effects, Interleukin-17 immunology, Interleukin-17 metabolism, Leukocytes, Mononuclear, Mice, Mice, Inbred C57BL, Mice, Transgenic, Nuclear Receptor Subfamily 1, Group F, Member 3 immunology, Primary Cell Culture, Psoriasis diagnosis, Psoriasis etiology, Psoriasis pathology, Severity of Illness Index, Skin drug effects, Skin immunology, Skin pathology, Sulfones therapeutic use, T-Lymphocytes, Helper-Inducer drug effects, T-Lymphocytes, Helper-Inducer immunology, Tetradecanoylphorbol Acetate toxicity, Treatment Outcome, Dermatologic Agents pharmacology, Nuclear Receptor Subfamily 1, Group F, Member 3 antagonists & inhibitors, Psoriasis drug therapy, Sulfones pharmacology
- Abstract
Background: Retinoic acid receptor-related orphan receptor gamma t (RORγt) has critical roles in the development, maintenance and function of interleukin (IL)-17-producing cells and is a highly attractive target for the treatment of IL-17-mediated autoimmune disease, particularly psoriasis. On the other hand, RORγt is also critical for controlling apoptosis during thymopoiesis, and genetic RORγt ablation or systematic RORγt inhibition cause progressive thymic aberrations leading to T cell lymphomas., Objective: We investigated whether topical administration of our novel RORγt inhibitor, S18-000003 has therapeutic potential for psoriasis with low risk of thymic aberrations., Methods: We evaluated the effect of topical S18-000003 on psoriasis-like skin inflammation and influence on the thymus in a 12-O-tetradecanoylphorbol-13-acetate-induced K14.Stat3C mouse psoriasis model., Results: S18-000003 markedly inhibited the development of psoriatic skin inflammation via suppression of the IL-17 pathway. In the skin, S18-000003 suppressed all subsets of IL-17-producing cells that we previously identified in this psoriasis model: Th17 cells, Tc17 cells, dermal γδ T cells, TCR
- cells that probably included innate lymphoid cells, and CD4- CD8- double-negative αβ T cells. Notably, neither reduction of CD4+ CD8+ double-positive thymocytes nor dysregulation of cell cycling was observed in S18-000003-treated mice, even at a high dose., Conclusion: Our topically administered RORγt inhibitor is a potential therapeutic agent for psoriasis with low risk of thymic lymphoma., (Copyright © 2019 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.)- Published
- 2019
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6. Discovery of a potent orally bioavailable retinoic acid receptor-related orphan receptor-gamma-t (RORγt) inhibitor, S18-000003.
- Author
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Sasaki Y, Odan M, Yamamoto S, Kida S, Ueyama A, Shimizu M, Haruna T, Watanabe A, and Okuno T
- Subjects
- Administration, Oral, Amides pharmacokinetics, Amides therapeutic use, Animals, Autoimmune Diseases drug therapy, Binding Sites, Binding, Competitive, Crystallography, X-Ray, Drug Evaluation, Preclinical, Half-Life, Humans, Interleukin-17 metabolism, Interleukin-23 pharmacology, Mice, Molecular Dynamics Simulation, Nuclear Receptor Subfamily 1, Group F, Member 3 metabolism, Protein Binding, Rats, Skin drug effects, Skin metabolism, Structure-Activity Relationship, Th17 Cells cytology, Th17 Cells drug effects, Th17 Cells metabolism, Amides chemistry, Nuclear Receptor Subfamily 1, Group F, Member 3 antagonists & inhibitors
- Abstract
The retinoic acid receptor-related orphan receptor-gamma-t (RORγt) is the master transcription factor responsible for regulating the development and function of T-helper 17 (Th17) cells, which are related to the pathology of several autoimmune disorders. Therefore, ROR
γ t is an attractive drug target for such Th17-mediated autoimmune diseases. A structure-activity relationship (SAR) study of lead compound 1 yielded a novel series of RORγ t inhibitors, represented by compound 6. Detailed SAR optimization, informed by X-ray cocrystal structure analysis, led to the discovery of a potent orally bioavailable RORγ t inhibitor 25, which inhibited IL-17 production in the skin of IL-23-treated mice by oral administration., (Copyright © 2018 Elsevier Ltd. All rights reserved.)- Published
- 2018
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7. An insurmountable NPY Y5 receptor antagonist exhibits superior anti-obesity effects in high-fat diet-induced obese mice.
- Author
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Fukasaka Y, Nambu H, Tanioka H, Obata A, Tonomura M, Okuno T, and Yukioka H
- Subjects
- Animals, Disease Models, Animal, Energy Metabolism drug effects, Injections, Intraventricular methods, Male, Mice, Inbred C57BL, Mice, Obese metabolism, Neuropeptide Y metabolism, Obesity metabolism, Diet, High-Fat adverse effects, Eating drug effects, Obesity drug therapy, Receptors, Neuropeptide Y antagonists & inhibitors, Receptors, Neuropeptide Y metabolism
- Abstract
Neuropeptide Y (NPY) Y5 receptor plays a key role in the effects of NPY, an important neurotransmitter in the control of energy homeostasis including stimulation of food intake and inhibition of energy expenditure. The NPY-Y5 receptor system has been an attractive drug target for potential use in treating obesity. Here we report the discovery and characterization of two novel Y5 receptor antagonists, S-2367 and S-234462. Both compounds displayed high affinity for the Y5 receptor in the radio-ligand binding assay, while in the cell-based functional assay, S-2367 and S-234462 showed, respectively, surmountable and insurmountable antagonism. In cell-based washout experiments, S-234462 dissociated from the Y5 receptor more slowly than S-2367. In vivo study showed that S-234462 effectively suppressed food intake induced by acute central injection of a selective Y5 receptor agonist. Furthermore, high-fat diet-induced obese (DIO) mice treated with S-234462 for 5 weeks showed a significant decrease in body weight gain and food intake compared to those treated with S-2367. In conclusion, S-234462 exhibits insurmountable antagonism of NPY Y5 receptor in vitro and superior anti-obesity effects to the surmountable NPY Y5 antagonist S-2367 in DIO mice., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
- Full Text
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8. Discovery of a novel olefin derivative as a highly potent and selective acetyl-CoA carboxylase 2 inhibitor with in vivo efficacy.
- Author
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Nishiura Y, Matsumura A, Kobayashi N, Shimazaki A, Sakamoto S, Kitade N, Tonomura Y, Ino A, and Okuno T
- Subjects
- Acetyl-CoA Carboxylase metabolism, Alkenes chemical synthesis, Alkenes chemistry, Animals, Dose-Response Relationship, Drug, Enzyme Inhibitors chemical synthesis, Enzyme Inhibitors chemistry, Humans, Mice, Mice, Inbred C57BL, Molecular Structure, Structure-Activity Relationship, Acetyl-CoA Carboxylase antagonists & inhibitors, Alkenes pharmacology, Drug Discovery, Enzyme Inhibitors pharmacology
- Abstract
Novel acetyl-CoA carboxylase 2 (ACC2) selective inhibitors were identified by the conversion of the alkyne unit of A-908292 to the olefin linker. Modification of the center and left part of the lead compound 1b improved the ACC2 inhibitory activity and CYP450 inhibition profile, and afforded a highly selective ACC2 inhibitor 2e which showed in vivo efficacy in C57BL/6 mice., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
- Full Text
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9. SN-38 Acts as a Radiosensitizer for Colorectal Cancer by Inhibiting the Radiation-induced Up-regulation of HIF-1α.
- Author
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Okuno T, Kawai K, Hata K, Murono K, Emoto S, Kaneko M, Sasaki K, Nishikawa T, Tanaka T, and Nozawa H
- Subjects
- Apoptosis drug effects, Apoptosis radiation effects, Camptothecin pharmacology, Cell Line, Tumor, Cell Proliferation drug effects, Cell Proliferation radiation effects, Colorectal Neoplasms metabolism, Colorectal Neoplasms pathology, G2 Phase Cell Cycle Checkpoints drug effects, G2 Phase Cell Cycle Checkpoints radiation effects, HT29 Cells, Humans, Irinotecan, S Phase drug effects, S Phase radiation effects, Up-Regulation radiation effects, Camptothecin analogs & derivatives, Hypoxia-Inducible Factor 1, alpha Subunit metabolism, Radiation-Sensitizing Agents pharmacology, Up-Regulation drug effects
- Abstract
Background/aim: Hypoxia offers resistance to therapy in human solid tumors. The aim of the study was to investigate whether SN-38, the active metabolite of irinotecan, acts as a radiosensitizer through inhibition of hypoxia-inducible factor (HIF)-1α in the human colorectal cancer (CRC) cells., Materials and Methods: HT29 and SW480 cells were cultured with SN-38 (0-4 μM) immediately after irradiation (0-8 Gy). HIF-1α expression was assessed using flow-cytometry and western blot analysis. Cell proliferation was evaluated by the calcein assay. Apoptosis and cell cycle were determined by flow-cytometry., Results: Radiation up-regulated HIF-1α, and SN-38 inhibited the radiation-induced HIF-1α. The combination of radiation and SN-38 inhibited cell proliferation more than radiation alone; treatment with SN-38 after radiation exposure did not increase the number of apoptotic cells, whereas, it enhanced the S and G
2 /M cell-cycle arrest and decreased the population of cells in G1 Conclusion: SN-38 inhibits the radiation-induced up-regulation of HIF-1α and acts as a radiosensitizer by inducing cell-cycle arrest in CRC cells., (Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)- Published
- 2018
- Full Text
- View/download PDF
10. Value of FDG-PET/CT Volumetry After Chemoradiotherapy in Rectal Cancer.
- Author
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Okuno T, Kawai K, Koyama K, Takahashi M, Ishihara S, Momose T, Morikawa T, Fukayama M, and Watanabe T
- Subjects
- Adult, Aged, Aged, 80 and over, Cohort Studies, Female, Fluorodeoxyglucose F18 administration & dosage, Humans, Male, Middle Aged, Neoplasm Recurrence, Local, Rectal Neoplasms metabolism, Rectal Neoplasms mortality, Retrospective Studies, Survival Rate, Treatment Outcome, Chemoradiotherapy methods, Cone-Beam Computed Tomography methods, Neoadjuvant Therapy methods, Positron Emission Tomography Computed Tomography methods, Rectal Neoplasms diagnostic imaging
- Abstract
Background: Neoadjuvant chemoradiotherapy followed by an optimal surgery is the standard treatment for patients with locally advanced rectal cancer. FDG-PET/CT is commonly used as the modality for assessing the effect of chemoradiotherapy., Objective: The purpose of this study was to investigate whether PET/CT-based volumetry could contribute to the prediction of pathological complete response or prognosis after neoadjuvant chemoradiotherapy., Design: This was a retrospective cohort study., Settings: This study was conducted at a single research center., Patients: Ninety-one consecutive patients with locally advanced rectal cancer were enrolled between January 2005 and December 2015., Intervention: Patients underwent PET/CT before and after neoadjuvant chemoradiotherapy., Main Outcome Measures: Maximum standardized uptake value and total lesion glycolysis on PET/CT before and after neoadjuvant chemoradiotherapy were calculated using isocontour methods. Correlations between these variables and clinicopathological factors and prognosis were assessed., Results: PET/CT-associated variables before chemoradiotherapy were not correlated with either clinicopathological factors or prognosis. Maximum standardized uptake value was associated with pathological complete response, but total lesion glycolysis was not. Maximum standardized uptake value correlated with ypT, whereas total lesion glycolysis correlated with both ypT and ypN. High total lesion glycolysis was associated with a considerably poorer prognosis; the 5-year recurrence rate was 65% and the 5-year mortality rate 42%, whereas in lesions with low total lesion glycolysis, these were 6% and 2%. On multivariate analysis, high total lesion glycolysis was an independent risk factor for recurrence (HR = 4.718; p = 0.04)., Limitations: The gain in fluoro-2-deoxy-D-glucose uptake may differ between scanners, thus the general applicability of this threshold should be validated., Conclusions: In patients with locally advanced rectal cancer, high total lesion glycolysis after neoadjuvant chemoradiotherapy is strongly associated with a worse prognosis. Total lesion glycolysis after chemoradiotherapy may be a promising preoperative predictor of recurrence and death. See Video Abstract at http://links.lww.com/DCR/A464.
- Published
- 2018
- Full Text
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11. A case of disseminated carcinomatosis of the bone marrow originating from gastric cancer 3 years after intraperitoneal chemotherapy against peritoneal carcinomatosis.
- Author
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Okuno T, Yamaguchi H, Kitayama J, Ishigami H, Nishikawa T, Tanaka J, Tanaka T, Kiyomatsu T, Hata K, Nozawa H, Kawai K, Kazama S, Ishihara S, Sunami E, and Watanabe T
- Subjects
- Bone Marrow Neoplasms pathology, Combined Modality Therapy, Disseminated Intravascular Coagulation, Female, Humans, Injections, Intraperitoneal, Middle Aged, Neoplasm Recurrence, Local pathology, Peritoneal Neoplasms pathology, Prognosis, Stomach Neoplasms pathology, Time Factors, Antineoplastic Combined Chemotherapy Protocols adverse effects, Bone Marrow Neoplasms etiology, Gastrectomy adverse effects, Neoplasm Recurrence, Local therapy, Peritoneal Neoplasms etiology, Stomach Neoplasms therapy
- Abstract
Background: Clinical studies of intraperitoneal chemotherapy with paclitaxel in patients of gastric cancer with peritoneal carcinomatosis is well tolerated and effective, and rare cases of metastasis and recurrence have experienced during the treatment. Disseminated carcinomatosis of the bone marrow is highly rare in gastric cancer and associated with a poor prognosis., Case Presentation: A 59-year-old woman of gastric cancer with peritoneal carcinomatosis received five courses of chemotherapy with intraperitoneal administration of paclitaxel, and laparoscopy showed disappearance of the peritoneal carcinomatosis. She subsequently underwent total gastrectomy, and the histopathological findings showed a complete response to the chemotherapy. Postoperatively, chemotherapy with intraperitoneal administration of paclitaxel was continued for 30 months, without apparent recurrence. However, the gastric cancer recurred as disseminated carcinomatosis of the bone marrow with disseminated intravascular coagulation, and we hence changed the chemotherapy regimen to weekly irinotecan. Remission was achieved, and she did not experience any major symptoms; however, she died 6 months after the diagnosis of disseminated carcinomatosis of the bone marrow., Conclusions: Since intraperitoneal paclitaxel administration can strongly suppress peritoneal carcinomatosis of gastric cancer, careful attention should be paid not only to peritoneal recurrence but also for rare site metastases, such as bone marrow metastases.
- Published
- 2016
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12. Identification of a novel benzimidazole derivative as a highly potent NPY Y5 receptor antagonist with an anti-obesity profile.
- Author
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Tamura Y, Hayashi K, Omori N, Nishiura Y, Watanabe K, Tanaka N, Fujioka M, Kouyama N, Yukimasa A, Tanaka Y, Chiba T, Tanioka H, Nambu H, Yukioka H, Sato H, and Okuno T
- Subjects
- Administration, Oral, Animals, Anti-Obesity Agents pharmacokinetics, Anti-Obesity Agents therapeutic use, Benzimidazoles pharmacokinetics, Benzimidazoles pharmacology, Benzimidazoles therapeutic use, Cytochrome P-450 Enzyme Inhibitors, Cytochrome P-450 Enzyme System metabolism, Half-Life, Mice, Obesity drug therapy, Rats, Receptors, Neuropeptide Y metabolism, Structure-Activity Relationship, Sulfones pharmacology, Sulfones therapeutic use, Weight Gain drug effects, Anti-Obesity Agents chemistry, Benzimidazoles chemistry, Receptors, Neuropeptide Y agonists, Sulfones chemistry
- Abstract
Optimization of HTS hit 1 for NPY Y5 receptor binding affinity, CYP450 inhibition, solubility and metabolic stability led to the identification of some orally available oxygen-linker derivatives for in vivo study. Among them, derivative 4i inhibited food intake induced by the NPY Y5 selective agonist, and chronic oral administration of 4i in DIO mice caused a dose-dependent reduction of body weight gain., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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13. Identification of a novel and orally available benzimidazole derivative as an NPY Y5 receptor antagonist with in vivo efficacy.
- Author
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Tamura Y, Omori N, Kouyama N, Nishiura Y, Hayashi K, Watanabe K, Tanaka Y, Chiba T, Yukioka H, Sato H, and Okuno T
- Subjects
- Administration, Oral, Animals, Drug Design, Drug Stability, Humans, Inhibitory Concentration 50, Mice, Mice, Obese, Protein Binding drug effects, Solubility, Structure-Activity Relationship, Benzimidazoles chemistry, Benzimidazoles pharmacology, Receptors, Neuropeptide Y antagonists & inhibitors
- Abstract
Optimization of lead compound 2 is described, mainly focusing on modification at the C-2 position of the benzimidazole core. Replacement of the phenyl linker of 2 with saturated rings resulted in identification of compound 8b which combines high Y5 receptor binding affinity with a good ADME profile leading to in vivo efficacy., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
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14. Design, synthesis and identification of novel benzimidazole derivatives as highly potent NPY Y5 receptor antagonists with attractive in vitro ADME profiles.
- Author
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Tamura Y, Omori N, Kouyama N, Nishiura Y, Hayashi K, Watanabe K, Tanaka Y, Chiba T, Yukioka H, Sato H, and Okuno T
- Subjects
- Animals, Benzimidazoles chemical synthesis, Benzimidazoles metabolism, Cytochrome P-450 Enzyme Inhibitors, Cytochrome P-450 Enzyme System metabolism, Drug Design, Humans, Mice, Microsomes, Liver metabolism, Obesity drug therapy, Pyridones chemical synthesis, Pyridones metabolism, Rats, Receptors, Neuropeptide Y metabolism, Benzimidazoles chemistry, Benzimidazoles pharmacology, Pyridones chemistry, Pyridones pharmacology, Receptors, Neuropeptide Y antagonists & inhibitors
- Abstract
Optimization of our HTS hit 1, mainly focused on modification at the C-2 position of the benzimidazole core, is described. Elimination of the flexible and metabolically labile -S-CH(2)- part and utilization of less lipophilic pyridone substructure led to identification of novel NPY Y5 receptor antagonists 6, which have low to sub-nanomolar Y5 receptor binding affinity with improved CYP450 inhibition profiles, good solubilities and high metabolic stabilities., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
- Full Text
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15. Hit to lead SAR study on benzoxazole derivatives for an NPY Y5 antagonist.
- Author
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Omori N, Kouyama N, Yukimasa A, Watanabe K, Yokota Y, Tanioka H, Nambu H, Yukioka H, Sato N, Tanaka Y, Sekiguchi K, and Okuno T
- Subjects
- Animals, Anti-Obesity Agents pharmacokinetics, Anti-Obesity Agents pharmacology, Benzoxazoles pharmacokinetics, Benzoxazoles pharmacology, Body Weight drug effects, Eating drug effects, Humans, Mice, Obesity metabolism, Rats, Receptors, Neuropeptide Y metabolism, Structure-Activity Relationship, Anti-Obesity Agents chemistry, Anti-Obesity Agents therapeutic use, Benzoxazoles chemistry, Benzoxazoles therapeutic use, Obesity drug therapy, Receptors, Neuropeptide Y antagonists & inhibitors
- Abstract
We report a hit to lead study on a novel benzoxazole NPY Y5 antagonist. Starting from HTS hit 1, structure-activity relationships were developed. Compound 12 showed reduction of food intake and a tendency to suppress body weight gain over the 21-day experimental period., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
- Full Text
- View/download PDF
16. Characterization of a novel inhibitor of cytosolic phospholipase A2alpha, pyrrophenone.
- Author
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Ono T, Yamada K, Chikazawa Y, Ueno M, Nakamoto S, Okuno T, and Seno K
- Subjects
- Arachidonic Acid metabolism, Calcimycin pharmacology, Cell Line, Crystallography, X-Ray, Cytosol enzymology, Dinoprostone biosynthesis, Glomerular Mesangium drug effects, Glomerular Mesangium metabolism, Group IV Phospholipases A2, Humans, Interleukin-1 pharmacology, Ionophores pharmacology, Lipolysis, Enzyme Inhibitors pharmacology, Phospholipases A antagonists & inhibitors, Pyrrolidines pharmacology
- Abstract
Cytosolic phospholipase A(2)alpha (cPLA(2)alpha), one of the three subtypes of cPLA(2) (alpha, beta and gamma), is thought to be a rate-limiting enzyme in eicosanoid biosynthesis. We developed a novel and potent cPLA(2)alpha inhibitor with an optically active pyrrolidine, termed pyrrophenone, and characterized this compound in detail using enzyme and cellular assay systems. Pyrrophenone, which shows strong inhibition of cPLA(2)alpha activity, is one of the most potent cPLA(2)alpha inhibitors reported to date. Similar inhibitory potencies for cPLA(2)alpha were obtained from three different assays. The inhibitory activity of pyrrophenone is two or three orders of magnitude more potent than arachidonyl trifluoromethyl ketone (AACOCF(3)) under the same assay conditions. Pyrrophenone shows reversible inhibition of cPLA(2)alpha and displays no characteristics of the slow-binding inhibition observed for AACOCF(3). Pyrrophenone also inhibited the esterase and lysophospholipase activities of cPLA(2)alpha. However, the inhibition by pyrrophenone of 14 kDa secretory PLA(2)s, types IB and IIA, was over two orders of magnitude less potent than that for cPLA(2)alpha. Pyrrophenone strongly inhibited arachidonic acid release in calcium ionophore (A23187)-stimulated human monocytic cells (THP-1 cells) in a dose-dependent manner with an IC(50) value of 0.024 microM, followed by suppression of eicosanoid synthesis, and also showed dose-dependent inhibition for interleukin-1-induced prostaglandin E(2) synthesis in human renal mesangial cells with an IC(50) value of 0.0081 microM. The mechanism of inhibition of eicosanoid synthesis in these cell-based assays was due to inhibition of only one step of arachidonic acid release without any effect on cyclo-oxygenase or lipoxygenase pathways. These results suggest that pyrrophenone could be a potential therapeutic agent for inflammatory diseases.
- Published
- 2002
- Full Text
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