PubMed | the Formulation Research, Daiichi University of Pharmacy, The Innovation Group, University of Toyama and Healthcare Global
Type: Journal Article | Journal: The Journal of biological chemistry | Year: 2016
Iron is an important biological catalyst and is critical for DNA synthesis during cell proliferation. Cellular iron uptake is enhanced in tumor cells to support increased DNA synthesis. Circadian variations in DNA synthesis and proliferation have been identified in tumor cells, but their relationship with intracellular iron levels is unclear. In this study, we identified a 24-h rhythm in iron regulatory protein 2 (IRP2) levels in colon-26 tumors implanted in mice. Our findings suggest that IRP2 regulates the 24-h rhythm of transferrin receptor 1 (Tfr1) mRNA expression post-transcriptionally, by binding to RNA stem-loop structures known as iron-response elements. We also found thatIrp2mRNA transcription is promoted by circadian clock genes, including brain and muscle Arnt-like 1 (BMAL1) and the circadian locomotor output cycles kaput (CLOCK) heterodimer. Moreover, growth in colon-26(19) tumors expressing the clock-mutant protein (CLOCK(19)) was low compared with that in wild-type colon-26 tumor. The time-dependent variation of cellular iron levels, and the proliferation rate in wild-type colon-26 tumor was decreased by CLOCK(19)expression. Our findings suggest that circadian organization contributes to tumor cell proliferation by regulating iron metabolism in the tumor.
Jiang R.,Hokuriku University |
Yamaori S.,Hokuriku University |
Takeda S.,Daiichi University of Pharmacy |
Yamamoto I.,Kyushu University of Health and Welfare |
Watanabe K.,Hokuriku University
Life Sciences | Year: 2011
Aims: Cannabidiol (CBD), one of the major constituents in marijuana, has been shown to be extensively metabolized by experimental animals and humans. However, human hepatic enzymes responsible for the CBD metabolism remain to be elucidated. In this study, we examined in vitro metabolism of CBD with human liver microsomes (HLMs) to clarify cytochrome P450 (CYP) isoforms involved in the CBD oxidations. Main methods: Oxidations of CBD in HLMs and recombinant human CYP enzymes were analyzed by gas chromatography/mass spectrometry. Key findings: CBD was metabolized by pooled HLMs to eightmonohydroxylated metabolites (6α-OH-, 6β-OH-, 7-OH-, 1″-OH-, 2″-OH-, 3″-OH-, 4″-OH-, and 5″-OH-CBDs). Among these metabolites, 6α-OH-, 6β-OH-, 7-OH-, and 4″-OH-CBDs were the major ones as estimated from the relative abundance of m/z 478, which was a predominant fragment ion of trimethylsilyl derivatives of the metabolites. Seven of 14 recombinant human CYP enzymes examined (CYP1A1, CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP3A4, and CYP3A5) were capable of metabolizing CBD. The correlations between CYP isoform-specific activities and CBD oxidative activities in 16 individual HLMs indicated that 6β-OH- and 4″-OH-CBDs were mainly formed by CYP3A4, which was supported by inhibition studies using ketoconazole and an anti-CYP3A4 antibody. The correlation and inhibition studies also showed that CBD 6α-hydroxylation was mainly catalyzed by CYP3A4 and CYP2C19, whereas CBD 7-hydroxylation was predominantly catalyzed by CYP2C19. Significance: This study indicated that CBD was extensively metabolized by HLMs. These results suggest that CYP3A4 and CYP2C19 may be major isoforms responsible for 6α-, 6β-, 7-, and/or 4″-hydroxylations of CBD in HLMs. © 2011 Elsevier Inc. All rights reserved.
Shimizu R.,Hiroshima International University |
Yamaguchi M.,Hiroshima International University |
Uramaru N.,Nihon Pharmaceutical University |
Kuroki H.,Daiichi University of Pharmacy |
And 3 more authors.
Toxicology | Year: 2013
The aim of this study was to investigate the possible influence of halogenated compounds on thyroid hormone metabolism via inhibition of iodotyrosine deiodinase (IYD) activity. The structure-activity relationships of 44 halogenated compounds for IYD-inhibitory activity were examined in vitro using microsomes of HEK-293 T cells expressing recombinant human IYD. The compounds examined were 17 polychlorinated biphenyls (PCBs), 15 polybrominated diphenyl ethers (PBDEs), two agrichemicals, five antiparasitics, two pharmaceuticals and three food colorants. Among them, 25 halogenated phenolic compounds inhibited IYD activity at the concentration of 1×10-4M or 6×10-4M. Rose bengal was the most potent inhibitor, followed by erythrosine B, phloxine B, benzbromarone, 4'-hydroxy-2,2',4-tribromodiphenyl ether, 4-hydroxy-2,3',3,4'-tetrabromodiphenyl ether, 4-hydroxy-2',3,4',5,6'-pentachlorobiphenyl, 4'-hydroxy-2,2',4,5'-tetrabromodiphenyl ether, triclosan, and 4-hydroxy-2,2',3,4',5-pentabromodiphenyl ether. However, among PCBs and PBDEs without a hydroxyl group, including their methoxylated metabolites, none inhibited IYD activity. These results suggest that halogenated compounds may disturb thyroid hormone homeostasis via inhibition of IYD, and that the structural requirements for IYD-inhibitory activity include halogen atom and hydroxyl group substitution on a phenyl ring. © 2013 Elsevier Ireland Ltd.
Ishii Y.,Kyushu University |
Takeda S.,Kyushu University |
Takeda S.,Daiichi University of Pharmacy |
Yamada H.,Kyushu University
Drug Metabolism Reviews | Year: 2010
Drug oxidation and conjugation mediated by cytochrome P450 (P450) and UDP-glucuronosyltransferase (UGT) have long been considered to take place separately. However, our recent studies have suggested that CYP3A4 specifically associates with UGT2B7 and alters the regioselectivity of morphine glucuronidation. This observation strongly supports the view that there is functional cooperation between P450 and UGT to facilitate multistep drug metabolism. In recent years, accumulating evidence has suggested an interaction between UGT isoforms or between P450 and UGTs and a change in UGT function by protein-protein association. In this review, we summarize these interactions and discuss their relevance to UGT function. © 2010 Informa UK Ltd.
Kuwano S.,Daiichi University of Pharmacy |
Masuda T.,Daiichi University of Pharmacy
Synthesis (Germany) | Year: 2016
The N-heterocyclic carbene (NHC)-catalyzed monoacylation of vicinal diols is described. Monoacylated compounds of 1,2-, 1,3-, and 1,4-diols are obtained in good yields and selectivity under mild reaction conditions at ambient temperature. © Georg Thieme Verlag Stuttgart, New York.
PubMed | Daiichi University of Pharmacy, Hiroshima International University and Kyushu University
Type: Journal Article | Journal: Anticancer research | Year: 2016
An in vitro cell model of long-term estrogen-deprived MCF-7 (LTED) cells has been utilized to analyze the re-growth mechanisms of breast cancers treated with blockers for estrogen receptor (ER) signaling. Bongkrekic acid (BKA) is a natural toxin isolated from coconut tempeh contaminated with the bacterium Burkholderia cocovenans.LTED cells, MCF-7 cells and MDA-MB-231 cells were employed in the study. After treatment with BKA (chemically synthesized; purity: >98%), several biochemical analyses were carried out.LTED cells were categorized into an oxidative phenotype. When LTED cells were treated with BKA, lactate dehydrogenase A (LDH-A)/pyruvate dehydrogenase kinase 4 (PDK4) were down-regulated, thereby prompting the aggressive use of glucose via mitochondrial oxidative phosphorylation and induction of cell death responses. These effects of BKA were not observed in the other breast cancer cells analyzed.We suggest the potential of BKA as an experimental tool for the analysis of cancer biology in LTED cells.
PubMed | Daiichi University of Pharmacy
Type: Journal Article | Journal: Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan | Year: 2016
Morphine with its potent analgesic property has been widely used for the treatment of various types of pain. However, the intrathecal (i.t.) administration of morphine at doses far higher than those required for antinociception exhibited nociceptive-related behaviors consisting of scratching, biting and licking, hyperalgesia, and allodynia in mice. Morphine-3-glucuronide (M3G), one of the major metabolites of morphine, has been found to evoke nociceptive behaviors similar to those after high-dose i.t. morphine. It is plausible that M3G may be responsible for nociception seen after high-dose i.t. morphine treatment. This article reviews the potential mechanism of spinally mediated nociceptive behaviors evoked by i.t. M3G in mice. We discuss the possible presynaptic release of nociceptive neurotransmitters/neuromodulators such as substance P, glutamate, dynorphin, and Leu-enkephalin in the primary afferent fibers following i.t. M3G administration. It is possible to speculate that i.t. M3G could indirectly activate NK1, NMDA, and 2-opioid receptors that lead to the release of nitric oxide (NO) in the dorsal spinal cord. The major function of NO is the production of cGMP and the activation of protein kinase G (PKG). The NO-cGMP-PKG pathway plays an important role in M3G-induced nociceptive behavior. The phosphorylation of extracellular signal-related kinase (ERK) in the dorsal spinal cord was also evoked via the NO-cGMP-PKG pathway through the activation of 2-opioid, NK1, and NMDA receptors, contributing to M3G-induced nociceptive behaviors. The demonstration of a neural mechanism underlying M3G-induced nociception provides a pharmacological basis for improved pain management with morphine at high doses.
PubMed | Japan National Institute of Advanced Industrial Science and Technology, Daiichi University of Pharmacy and Hiroshima International University
Type: Journal Article | Journal: Journal of natural medicines | Year: 2016
The physiological activities of cannabidiolic acid (CBDA), a component of fiber-type cannabis plants, have been demonstrated and include its function as a protector against external invasion by inducing cannabinoid-mediated necrosis (Shoyama et al., Plant Signal Behav 3:1111-1112, 2008). The biological activities of CBDA have been attracting increasing attention. We previously identified CBDA as an inhibitor of the migration of MDA-MB-231 cells, a widely used human breast cancer cell line in cancer biology, due to its highly aggressive nature. The chemical inhibition and down-regulation of cyclooxygenase-2 (COX-2), the expression of which has been detected in ~40% of human invasive breast cancers, are suggested to be involved in the CBDA-mediated abrogation of cell migration. However, the molecular mechanism(s) responsible for the CBDA-induced down-regulation of COX-2 in MDA-MB-231 cells have not yet been elucidated. In the present study, we describe a possible mechanism by which CBDA abrogates the expression of COX-2 via the selective down-regulation of c-fos, one component of the activator protein-1 (AP-1) dimer complex, a transcription factor for the positive regulation of the COX-2 gene.
PubMed | Daiichi University of Pharmacy, Saiseikai Nagasaki Hospital, Kyushu University and NMedical Co. Ouryokukai
Type: | Journal: EBioMedicine | Year: 2016
Chronic kidney disease (CKD) is a global health problem, and novel therapies to treat CKD are urgently needed. Here, we show that inhibition of G
PubMed | Kobe University, Kyushu University, Neues Corporation, University of Fukui and 2 more.
Type: Journal Article | Journal: The Journal of biological chemistry | Year: 2016
Chronic kidney disease (CKD) is associated with an increase in serum retinol; however, the underlying mechanisms of this disorder are poorly characterized. Here, we found that the alteration of hepatic metabolism induced the accumulation of serum retinol in 5/6 nephrectomy (5/6Nx) mice. The liver is the major organ responsible for retinol metabolism; accordingly, microarray analysis revealed that the hepatic expression of most CYP genes was changed in 5/6Nx mice. In addition, D-box-binding protein (DBP), which controls the expression of several CYP genes, was significantly decreased in these mice. Cyp3a11 and Cyp26a1, encoding key proteins in retinol metabolism, showed the greatest decrease in expression in 5/6Nx mice, a process mediated by the decreased expression of DBP. Furthermore, an increase of plasma transforming growth factor-1 (TGF-1) in 5/6Nx mice led to the decreased expression of the Dbp gene. Consistent with these findings, the alterations of retinol metabolism and renal dysfunction in 5/6Nx mice were ameliorated by administration of an anti-TGF-1 antibody. We also show that the accumulation of serum retinol induced renal apoptosis in 5/6Nx mice fed a normal diet, whereas renal dysfunction was reduced in mice fed a retinol-free diet. These findings indicate that constitutive Dbp expression plays an important role in mediating hepatic dysfunction under CKD. Thus, the aggravation of renal dysfunction in patients with CKD might be prevented by a recovery of hepatic function, potentially through therapies targeting DBP and retinol.