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Lyu J, Imachi H, Yoshimoto T, Fukunaga K, Sato S, Ibata T, Kobayashi T, Dong T, Yonezaki K, Yamaji N, Kikuchi F, Iwama H, Ishikawa R, Haba R, Sugiyama Y, Zhang H, Murao K. Thyroid stimulating hormone stimulates the expression of glucose transporter 2 via its receptor in pancreatic β cell line, INS-1 cells. Sci Rep 2018; 8:1986. [PMID: 29386586 PMCID: PMC5792451 DOI: 10.1038/s41598-018-20449-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 01/17/2018] [Indexed: 12/30/2022] Open
Abstract
Thyroid stimulating hormone (TSH) stimulates the secretion of thyroid hormones by binding the TSH receptor (TSHR). TSHR is well-known to be expressed in thyroid tissue, excepting it, TSHR has also been expressed in many other tissues. In this study, we have examined the expression of TSHR in rat pancreatic islets and evaluated the role of TSH in regulating pancreas-specific gene expression. TSHR was confirmed to be expressed in rodent pancreatic islets and its cell line, INS-1 cells. TSH directly affected the glucose uptake in INS cells by up-regulating the expression of GLUT2, and furthermore this process was blocked by SB203580, the specific inhibitor of the p38 MAPK signaling pathway. Similarly, TSH stimulated GLUT2 promoter activity, while both a dominant-negative p38MAPK α isoform (p38MAPK α-DN) and the specific inhibitor for p38MAPK α abolished the stimulatory effect of TSH on GLUT2 promoter activity. Finally, INS-1 cells treated with TSH showed increased protein level of glucokinase and enhanced glucose-stimulated insulin secretion. Together, these results confirm that TSHR is expressed in INS-1 cells and rat pancreatic islets, and suggest that activation of the p38MAPK α might be required for TSH-induced GLUT2 gene transcription in pancreatic β cells.
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Fukunaga K, Yabuki Y, Owada Y, Shinoda Y. FABP3 promotes α-synuclein oligomerization in parkinson’s disease. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Shioda N, Yabuki Y, Wang Y, Uchigashima M, Hikida T, Sasaoka T, Mori H, Watanabe M, Sasahara M, Fukunaga K. Endocytosis following dopamine D 2 receptor activation is critical for neuronal activity and dendritic spine formation via Rabex-5/PDGFRβ signaling in striatopallidal medium spiny neurons. Mol Psychiatry 2017; 22:1205-1222. [PMID: 27922607 DOI: 10.1038/mp.2016.200] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 09/28/2016] [Accepted: 10/04/2016] [Indexed: 02/06/2023]
Abstract
Aberrant dopamine D2 receptor (D2R) activity is associated with neuropsychiatric disorders, making those receptors targets for antipsychotic drugs. Here, we report that novel signaling through the intracellularly localized D2R long isoform (D2LR) elicits extracellular signal-regulated kinase (ERK) activation and dendritic spine formation through Rabex-5/platelet-derived growth factor receptor-β (PDGFRβ)-mediated endocytosis in mouse striatum. We found that D2LR directly binds to and activates Rabex-5, promoting early-endosome formation. Endosomes containing D2LR and PDGFRβ are then transported to the Golgi apparatus, where those complexes trigger Gαi3-mediated ERK signaling. Loss of intracellular D2LR-mediated ERK activation decreased neuronal activity and dendritic spine density in striatopallidal medium spiny neurons (MSNs). In addition, dendritic spine density in striatopallidal MSNs significantly increased following treatment of striatal slices from wild-type mice with quinpirole, a D2R agonist, but those changes were lacking in D2LR knockout mice. Moreover, intracellular D2LR signaling mediated effects of a typical antipsychotic drug, haloperidol, in inducing catalepsy behavior. Taken together, intracellular D2LR signaling through Rabex-5/PDGFRβ is critical for ERK activation, dendritic spine formation and neuronal activity in striatopallidal MSNs of mice.
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Zhang XZ, Imachi H, Lyu JY, Fukunaga K, Sato S, Ibata T, Kobayashi T, Yoshimoto T, Kikuchi F, Dong T, Murao K. Prolactin regulatory element-binding protein is involved in suppression of the adiponectin gene in vivo. J Endocrinol Invest 2017; 40:437-445. [PMID: 27914036 DOI: 10.1007/s40618-016-0589-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 11/25/2016] [Indexed: 10/20/2022]
Abstract
PURPOSE Prolactin regulatory element-binding protein (PREB), a member of the WD-repeat protein family, has been recognized as a transcriptional factor that regulates prolactin promoter activity in the anterior pituitary of rats. PREB is expressed not only in the pituitary but also in various other tissues, including the adipose tissue. Previous studies have shown that PREB acts as a transcriptional regulator and suppresses the expression of the adiponectin gene in cultured 3T3L1 preadipocytes. The aim of this study was to further examine the potential role of PREB in adipose tissue in vivo. METHODS Transgenic mice that overexpressing PREB (PREB transgenic mice) were generated. Insulin resistance was evaluated in PREB transgenic mice using glucose and insulin tolerance tests. Adiponectin expression in the adipose tissue was examined by western blot analysis and quantitative polymerase chain reaction (qPCR). The expression levels of stearoyl-CoA desaturase (Scd) and adiponectin receptor 2(ADIPOR2) were quantified by qPCR. RESULTS Glucose and insulin tolerance tests revealed insulin resistance in PREB transgenic mice. Serum adiponectin and leptin concentrations were decreased. Adiponectin gene expression was decreased in the adipose tissue, which was confirmed by the downregulation of the adiponectin-dependent hepatic Scd gene and upregulation of the ADIPOR2 gene in the liver of PREB transgenic mice. We also found that pioglitazone, an agonist for the peroxisome proliferator-activated receptor-r, improved the insulin resistance in the PREB transgenic mice after a 10-day feeding period. CONCLUSIONS These results demonstrated that PREB might contribute to the regulation of adiponectin gene expression in vivo.
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Murao K, Imachi H, Yoshimoto T, Kikuchi F, Fukunaga K. [Current status and issues of clinical-pass in diabetes]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 2016; 74 Suppl 2:673-677. [PMID: 27266173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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Sawa Y, Matsuda K, Tatsumi E, Matsumiya G, Tsukiya T, Abe T, Fukunaga K, Kishida A, Kokubo K, Masuzawa T, Myoui A, Nishimura M, Nishimura T, Nishinaka T, Okamoto E, Tokunaga S, Tomo T, Yagi Y, Yamaoka T. Journal of Artificial Organs 2015: the year in review : Journal of Artificial Organs Editorial Committee. J Artif Organs 2016; 19:1-7. [PMID: 26896942 DOI: 10.1007/s10047-016-0886-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Indexed: 11/30/2022]
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Lyu J, Imachi H, Fukunaga K, Yoshimoto T, Zhang H, Murao K. Roles of lipoprotein receptors in the entry of hepatitis C virus. World J Hepatol 2015; 7:2535-2542. [PMID: 26527170 PMCID: PMC4621467 DOI: 10.4254/wjh.v7.i24.2535] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 08/07/2015] [Accepted: 09/28/2015] [Indexed: 02/06/2023] Open
Abstract
Infection by hepatitis C virus (HCV), a plus-stranded RNA virus that can cause cirrhosis and hepatocellular carcinoma, is one of the major health problems in the world. HCV infection is considered as a multi-step complex process and correlated with abnormal metabolism of lipoprotein. In addition, virus attacks hepatocytes by the initial attaching viral envelop glycoprotein E1/E2 to receptors of lipoproteins on host cells. With the development of HCV model system, mechanisms of HCV cell entry through lipoprotein uptake and its receptor have been extensively studied in detail. Here we summarize recent knowledge about the role of lipoprotein receptors, scavenger receptor class B type I and low-density lipoprotein receptor in the entry of HCV, providing a foundation of novel targeting therapeutic tools against HCV infection.
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Wakita S, Yamaguchi H, Ueki T, Usuki K, Kurosawa S, Kobayashi Y, Kawata E, Tajika K, Gomi S, Koizumi M, Fujiwara Y, Yui S, Fukunaga K, Ryotokuji T, Hirakawa T, Arai K, Kitano T, Kosaka F, Tamai H, Nakayama K, Fukuda T, Inokuchi K. Complex molecular genetic abnormalities involving three or more genetic mutations are important prognostic factors for acute myeloid leukemia. Leukemia 2015; 30:545-54. [DOI: 10.1038/leu.2015.288] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Revised: 10/04/2015] [Accepted: 10/07/2015] [Indexed: 01/07/2023]
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Sawa Y, Matsuda K, Tatsumi E, Matsumiya G, Abe T, Fukunaga K, Kishida A, Kokubo K, Masuzawa T, Myoui A, Nishimura M, Nishimura T, Nishinaka T, Okamoto E, Tokunaga S, Tomo T, Tsukiya T, Yagi Y, Yamaoka T. Journal of Artificial Organs 2014: the year in review. J Artif Organs 2015; 18:1-7. [PMID: 25701365 DOI: 10.1007/s10047-015-0821-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Indexed: 12/18/2022]
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Islam M, Moriguchi S, Tagashira H, Fukunaga K. Rivastigmine improves hippocampal neurogenesis and depression-like behaviors via 5-HT1A receptor stimulation in olfactory bulbectomized mice. Neuroscience 2014; 272:116-30. [DOI: 10.1016/j.neuroscience.2014.04.046] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 04/23/2014] [Accepted: 04/23/2014] [Indexed: 11/29/2022]
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Daikuhara H, Fukunaga K, Ohshima T. Difference in the effects of switching from candesartan to olmesartan or telmisartan to olmesartan in hypertensive patients with type 2 diabetes: the COTO study. DRUG DESIGN DEVELOPMENT AND THERAPY 2014; 8:219-26. [PMID: 24600204 PMCID: PMC3933665 DOI: 10.2147/dddt.s53253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Purpose This open-label controlled study compared the therapeutic efficacy of three representative angiotensin II receptor blockers (ARBs) in hypertensive patients with type 2 diabetes attending a hospital outpatient clinic. The primary measure in this study was morning home blood pressure (BP). Patients and methods Two studies were done concurrently to investigate the effects of switching from two different ARBs to olmesartan. Patients prescribed candesartan (8 mg once daily in the morning) or telmisartan (40 mg once daily in the morning) for 16 weeks were switched to olmesartan (20 mg once daily in the morning) for 16 weeks. Then, they were switched back to candesartan (CO group) or telmisartan (TO group) for another 16 weeks. Results Data from all patients in the CO group (n=165) and the TO group (n=152) were analyzed. Clinic and morning home BP and urinary albumin levels showed a significant decrease from baseline at 16 weeks after switching to olmesartan in both the CO and the TO group (clinic BP, morning home diastolic BP, and urinary albumin, P<0.05; morning home systolic BP, P<0.01). In contrast, clinic BP, morning home BP, and urinary albumin were significantly increased again 16 weeks after switching back to candesartan or telmisartan (clinic BP, morning home diastolic BP, and urinary albumin, P<0.05; morning home systolic BP, P<0.01). No subjects experienced an adverse reaction that required withdrawal from the study. No adverse reactions attributable to the study drugs were observed. Conclusion Olmesartan is a promising ARB for BP control in hypertensive type 2 diabetics.
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Yabuki Y, Fukunaga K. Oral administration of glutathione improves memory deficits following transient brain ischemia by reducing brain oxidative stress. Neuroscience 2013; 250:394-407. [DOI: 10.1016/j.neuroscience.2013.07.017] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 07/07/2013] [Accepted: 07/09/2013] [Indexed: 11/16/2022]
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Yabuki Y, Nakagawasai O, Moriguchi S, Shioda N, Onogi H, Tan-No K, Tadano T, Fukunaga K. Decreased CaMKII and PKC activities in specific brain regions are associated with cognitive impairment in neonatal ventral hippocampus-lesioned rats. Neuroscience 2013; 234:103-15. [DOI: 10.1016/j.neuroscience.2012.12.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 12/22/2012] [Accepted: 12/28/2012] [Indexed: 11/28/2022]
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Sawa Y, Tatsumi E, Tsukiya T, Matsuda K, Fukunaga K, Kishida A, Masuzawa T, Matsumiya G, Myoui A, Nishimura M, Nishimura T, Nishinaka T, Okamoto E, Tokunaga S, Tomo T, Yagi Y, Yamaoka T. Journal of Artificial Organs 2012: the year in review. J Artif Organs 2013; 16:1-8. [PMID: 23456197 DOI: 10.1007/s10047-013-0690-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Indexed: 12/19/2022]
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Oshima G, Shinoda M, Tanabe M, Ebinuma H, Nishiyama R, Takano K, Yamada S, Miyasho T, Masugi Y, Matsuda S, Suda K, Fukunaga K, Matsubara K, Hibi T, Yagi H, Hayashida T, Yamagishi Y, Obara H, Itano O, Takeuchi H, Kawachi S, Saito H, Hibi T, Maruyama I, Kitagawa Y. Increased plasma levels of high mobility group box 1 in patients with acute liver failure. ACTA ACUST UNITED AC 2012; 48:154-62. [PMID: 22585050 DOI: 10.1159/000338363] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 03/07/2012] [Indexed: 11/19/2022]
Abstract
BACKGROUND High-mobility group box 1 (HMGB1) is a monocyte-derived late-acting inflammatory mediator, which is released in conditions such as shock, tissue injury and endotoxin-induced lethality. In this study, we determined the plasma and hepatic tissue levels of HMGB1 in patients with acute liver failure (ALF). PATIENTS AND METHODS We determined the plasma levels of HMGB1 and aspartate aminotransferase (AST) in 7 healthy volunteers (HVs), 40 patients with liver cirrhosis (LC), 37 patients with chronic hepatitis (CH), 18 patients with severe acute hepatitis (AH), and 14 patients with fulminant hepatitis (FH). The 14 patients with FH were divided into two subgroups depending upon the history of plasma exchange (PE) before their plasma sample collection. The hepatic levels of HMGB1 were measured in tissue samples from 3 patients with FH who underwent living-donor liver transplantation and from 3 healthy living donors. Hepatic tissue samples were also subjected to immunohistochemical examination for HMGB1. RESULTS The plasma levels of HMGB1 (ng/ml) were higher in patients with liver diseases, especially in FH patients with no history of PE, than in HVs (0.3 ± 0.3 in HVs, 4.0 ± 2.0 in LC, 5.2 ± 2.6 in CH, 8.6 ± 4.8 in severe AH, 7.8 ± 2.7 in FH with a history of PE, and 12.5 ± 2.6 in FH with no history of PE, p < 0.05 in each comparison). There was a strong and statistically significant relationship between the mean plasma HMGB1 level and the logarithm of the mean AST level (R = 0.900, p < 0.05). The hepatic tissue levels of HMGB1 (ng/mg tissue protein) were lower in patients with FH than in healthy donors (539 ± 116 in FH vs. 874 ± 81 in healthy donors, p < 0.05). Immunohistochemical staining for HMGB1 was strong and clear in the nuclei of hepatocytes in liver sections from healthy donors, but little staining in either nuclei or cytoplasm was evident in specimens from patients with FH. CONCLUSION We confirmed that plasma HMGB1 levels were increased in patients with ALF. Based on a comparison between HMGB1 contents in normal and ALF livers, it is very likely that HMGB1 is released from injured liver tissue.
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Fukunaga K, Orito K. Time-course effects of St John's wort on the pharmacokinetics of cyclosporine in dogs: interactions between herbal extracts and drugs. J Vet Pharmacol Ther 2011; 35:446-51. [PMID: 22091645 DOI: 10.1111/j.1365-2885.2011.01348.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To clarify the interaction between St John's wort (SJW) and cyclosporine (CsA) in dogs, the pharmacokinetics of CsA before and during the repeated administration of SJW were analyzed. In the SJW group, SJW (300 mg) was given orally to four dogs every 24 h for 14 days. A single dose of CsA (5 mg/kg) was given orally 7 days before and 7 and 14 days after the initiation of the repeated administration of SJW. In the Control group, a single dose of CsA (5 mg/kg) was given orally to four other dogs in accordance with that in the SJW group. Blood samples from both groups were collected, and whole-blood concentrations of CsA were determined using high-performance liquid chromatography with UV detection. The maximum whole-blood concentration and AUC(0-∞) of the SJW group were significantly lower and the CL(tot) /F and V(d) /F were significantly higher than those in the Control group 7 and 14 days after the initiation of repeated SJW. Thus, repeated administrations of SJW affect the pharmacokinetic profiles of CsA in dogs. Further studies are necessary to elucidate the mechanisms of interaction between SJW and CsA in dogs.
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Oshiro Y, Sasaki R, Kobayashi A, Murata S, Fukunaga K, Kondo T, Oda T, Ohkohchi N. Prognostic relevance of the lymph node ratio in surgical patients with extrahepatic cholangiocarcinoma. Eur J Surg Oncol 2010; 37:60-4. [PMID: 21094016 DOI: 10.1016/j.ejso.2010.10.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Revised: 09/15/2010] [Accepted: 10/26/2010] [Indexed: 02/08/2023] Open
Abstract
AIM Few studies have investigated the influence of the lymph node ratio (LNR), the ratio of the number of lymph nodes harboring metastatic cancer to the total number of lymph nodes removed, on the outcome after surgery for extrahepatic cholangiocarcinoma. This study was conducted to examine the prognostic impact of LNR in patients undergoing resection for extrahepatic cholangiocarcinoma. PATIENTS AND METHODS We retrospectively analyzed a total of 60 consecutive patients who underwent resection for extrahepatic cholangiocarcinoma. We focused on the LNR, which was classified as 0 in 34 patients, between 0 and 0.2 in 13 patients, and greater than 0.2 in 13 patients. RESULTS The overall five-year survival rates for patients with LNRs of 0, 0 to 0.2, and ≥0.2 were 44%, 10%, and 0%, respectively (p = 0.023). LNR was an independent predictive factor for estimated survival by both univariate (p = 0.016) and multivariate (p = 0.022) analyses including LNR, the sites of the primary tumors, and surgical margin as the variables. There were no statistically significant differences between patients who had less than 12 lymph nodes removed and those who had 12 or more lymph nodes removed (p = 0.484). CONCLUSION LNR was a powerful, independent predictor of estimated survival in patients undergoing surgical resection for extrahepatic cholangiocarcinoma. LNR should be considered when stratifying patients for future clinical trials.
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Nagase K, Fukunaga K, Yokoyama Y, Kamikozuru K, Kikuyama R, Kato K, Yamada M, Miwa H, Matsumoto T. 31 Cytokine profiles during the granulocyte/monocyte apheresis for Crohn's disease. Transfus Apher Sci 2010. [DOI: 10.1016/s1473-0502(10)70038-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Yokoyama Y, Fukunaga K, Kamikozuru K, Nagase K, Katou K, Kikuyama R, Takeda N, Matsumoto T. 22 The predictive markers of response for cytapheresis in active ulcerative colitis. Transfus Apher Sci 2010. [DOI: 10.1016/s1473-0502(10)70021-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Fukunaga K. 6 Development of optimum therapeutic strategy for refractory ulcerative colitis with acute flare: current status of the CELLSORBA leukocytapheresis in Japan. Transfus Apher Sci 2010. [DOI: 10.1016/s1473-0502(10)70009-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Fukunaga K, Fujii Y, Chiba N, Ueshima A, Wakao Y, Mishima K, Fujiwara M, Orito K. Pharmacokinetics of nicorandil in dogs with mild mitral regurgitation. Res Vet Sci 2010; 90:95-8. [PMID: 20488500 DOI: 10.1016/j.rvsc.2010.04.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Revised: 04/02/2010] [Accepted: 04/19/2010] [Indexed: 11/26/2022]
Abstract
The aim of this study was to examine the pharmacokinetics of nicorandil, a hybrid of an adenosine triphosphate-sensitive potassium channel opener and a nitrate, and to estimate its clinical doses in dogs with mild mitral valve regurgitation (MR). Nicorandil (0.1, 0.3, and 1.0 mg/kg) was administered orally to normal dogs and those with experimentally-induced MR, and its plasma concentrations were analyzed using high-performance liquid chromatography. Plasma concentrations increased dose-dependently after the administration of nicorandil, and were not different between normal dogs and those with MR. Similar to the effective plasma values obtained in cardiac disease in humans, the findings of this pharmacokinetic study may indicate that a dose of 0.3-1.0 mg/kg has the same effectiveness in dogs with cardiac dysfunction.
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Yamada K, Oda T, Hashimoto S, Ohara Y, Kobayashi A, Fukunaga K, Murata S, Sasaki R, Ohkohchi N. Treatment of locally advanced pancreatic cancer with concurrent chemoradiotherapy with gemcitabine: Results from 24 patients treated from 2003-2009. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e14684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Hashimoto S, Oda T, Yamada K, Ohara Y, Kobayashi A, Fukunaga K, Murata S, Sasaki R, Ohkohchi N. Effect of continuous adjuvant chemotherapy and protracted treatment on recurrence and survival in resected pancreatic adenocarcinoma. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e14676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Miyata J, Asano K, Fukunaga K, Takihara T, Ohmari N, Kodama M, Tomomatsu K, Ogura H, Tanaka K, Kamiishi N, Niimi K, Oguma T, Sayama K, Takamiya R, Ishizaka A. Effects of Anti-inflammatory Lipid Mediator, Protectin D1, on Human Eosinophil Functions. J Allergy Clin Immunol 2010. [DOI: 10.1016/j.jaci.2009.12.718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Moriguchi S, Shioda N, Yamamoto Y, Fukunaga K. Platelet-activating factor-induced synaptic facilitation is associated with increased calcium/calmodulin-dependent protein kinase II, protein kinase C and extracellular signal-regulated kinase activities in the rat hippocampal CA1 region. Neuroscience 2010; 166:1158-66. [PMID: 20074623 DOI: 10.1016/j.neuroscience.2010.01.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Revised: 01/05/2010] [Accepted: 01/05/2010] [Indexed: 12/01/2022]
Abstract
Platelet-activating factor (PAF) is an important inflammatory lipid mediator affecting neural plasticity. In the present study, we demonstrated how PAF affects synaptic efficacy through activation of protein kinases in the rat hippocampal CA1 region. In cultured hippocampal neurons, 10 to 1000 nM PAF stimulated autophosphorylation of calcium/calmodulin-dependent protein kinase II (CaMKII) and phosphorylation of synapsin I and myristoylated alanine-rich protein kinase C substrate (MARCKS). In hippocampal CA1 slices, field excitatory postsynaptic potentials (fEPSPs) induced by stimulation of the Schaffer collateral/commissural pathways were significantly increased 10-50 min after exposure to 100 to 1000 nM PAF. Immunoblotting analysis showed that 100 nM PAF treatment for 10 or 50 min significantly and persistently increased CaMKII autophosphorylation in the hippocampal CA1 region. Increased protein kinase Calpha (PKCalpha) autophosphorylation was also seen at the same time point after PAF exposure. By contrast, extracellular signal-regulated kinase (ERK) phosphorylation was slightly but significantly increased at 10 min after PAF exposure. Consistent with increased CaMKII autophosphorylation, AMPA-type glutamate receptor subunit 1 (GluR1) (Ser-831) phosphorylation as a CaMKII postsynaptic substrate significantly increased after 10 or 50 min of treatment, whereas synapsin I (Ser-603) phosphorylation as a presynaptic substrate increased at 10 min in the hippocampal CA1 region. Phosphorylation of MARCKS (Ser-152/156) and NMDA receptor subunit 1 (NR1) (Ser-896) as PKCalpha substrates also significantly increased after 10 min but had not further increased by 50 min in the CA1 region. Increased of fEPSPs induced by PAF treatment completely and/or partly inhibited by KN93 and/or U0126 treatment. These results suggest that PAF induces synaptic facilitation through activation of CaMKII, PKC and ERK in the hippocampal CA1 region.
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