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1.
Biol Pharm Bull ; 45(7): 881-887, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35474184

ABSTRACT

To identify patients at a high risk for primary and secondary osteoporotic fractures using fracture risk assessments performed using the current method and the proposed method, in an acute care hospital and to identify departments where high-risk patients are admitted. This retrospective study included patients aged 40-90 years who were hospitalized at Fujita Health University Hospital. We collated the clinical data and prescriptions of all study participants. We also gathered data pertaining to risk factors according to Fracture Risk Assessment Tool (FRAX). Of the 1595 patients, the mean number of major osteoporotic fracture risk predicted using FRAX was 11.73%. The department of rheumatology showed the highest fracture risk (18.55 ± 16.81) and had the highest number of patients on medications that resulted in reduced bone mineral density (1.07 ± 0.98 medication). Based on the FRAX, the proportion of patients in the high-risk group in this department was significantly higher compared with those in the remaining departments with respect to glucocorticoid administration, rheumatoid arthritis, and secondary osteoporosis. However, the departments included in the high-risk group were not necessarily the same as the departments included in the top group, based on the administered medications. FRAX score is calculated based on various risk factors; however, only glucocorticoid corresponds to medications. We should focus on medication prescription patterns in addition to FRAX to improve fracture risk assessment in hospital-wide surveillance. Therefore, we recommend the use of FRAX along with the prescribed medications to identify departments that admit high-risk patients.


Subject(s)
Bone Density , Osteoporotic Fractures , Glucocorticoids , Hospitals , Humans , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/etiology , Osteoporotic Fractures/prevention & control , Retrospective Studies , Risk Assessment , Risk Factors
2.
Nanoscale ; 13(3): 1784-1790, 2021 Jan 28.
Article in English | MEDLINE | ID: mdl-33433554

ABSTRACT

Plasmon-induced chemical reactions triggered by near-infrared light illumination might enable efficient photo energy conversion. Here, electrochemical oxidative polymerization of a conductive polymer was conducted on plasmonic photoconversion electrodes. The absolute electrochemical potential of the generated holes was estimated from the redox potentials of the monomers. In addition, well-defined plasmonic structures were examined to better understand the relationship between the excited plasmon mode and spatial distribution of reaction active sites. Rod structures with various lengths had distinct spatial distributions of reaction active sites that depended on the higher plasmon modes, as visualized by Raman measurements.

3.
Biomedicines ; 8(7)2020 Jun 27.
Article in English | MEDLINE | ID: mdl-32605038

ABSTRACT

We previously showed that ergosterol has an inhibitory effect on bladder carcinogenesis. In this study, we aimed to elucidate the molecular mechanism by which ergosterol inhibits bladder carcinogenesis using a rat model of N-butyl-N-(4-hydroxybutyl)nitrosamine-induced bladder cancer. The messenger ribonucleic acid (mRNA) expression level of the cell cycle-related gene cyclin D1 and inflammation-related gene cyclooxygenase-2 in bladder epithelial cells was significantly increased in the carcinogenesis group compared with the control group. In contrast, in ergosterol-treated rats, these increases were significantly suppressed. Ergosterol did not affect the plasma testosterone concentration or the binding of dihydrotestosterone to androgen receptor (AR). The mRNA expression levels of 5α-reductase type 2 and AR were higher in the carcinogenesis group than in the control group but were significantly decreased by ergosterol administration. These results suggest that ergosterol inhibits bladder carcinogenesis by modulating various aspects of the cell cycle, inflammation-related signaling, and androgen signaling. Future clinical application of the preventive effect of ergosterol on bladder carcinogenesis is expected.

4.
Chemosphere ; 228: 513-520, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31051354

ABSTRACT

We explored the effects of gas emission by mixtures undergoing alkali-activation of municipal solid waste incineration fly ash (MSWIFA) and pyrophyllite (the mixtures included dehydrated pyrophyllite, MSWIFA, 14 mol/L aqueous sodium hydroxide, and sodium silicate; curing proceed at 105 °C for 24 h). We measured the compressive strengths of the derived solid composites. The causes of gas emission, and the physical and chemical properties of products created under controlled gas emission, were investigated. Hydrogen was emitted after mixing MSWIFA and alkali. The compressive strength of products prepared when gas emission was complete was 2-3.4-fold greater than that of products prepared when gas emission was incomplete. X-ray micro-tomography and mercury intrusion porosimetry showed that products formed during complete gas emission tended to have smaller pores. X-ray diffraction and nuclear magnetic resonance (27Al and 29Si) indicated that the aluminum substitution levels in tectosilicate differed under such conditions, although the minerals were identical. Thus, complete gas emission after mixing improved ultimate products.


Subject(s)
Aluminum Silicates/chemistry , Coal Ash/chemistry , Incineration/methods , Oil and Gas Industry/methods , Solid Waste/analysis , Carbon/chemistry
5.
Sci Rep ; 9(1): 2364, 2019 02 20.
Article in English | MEDLINE | ID: mdl-30787375

ABSTRACT

Allopregnanolone (ALLO) is a neurosteroid produced in the brain, but so far, no study has explored its link with itching. Herein, we used a diet-induced atopic dermatitis mouse model to examine whether exogenously administered and endogenously produced ALLO contribute to inducing scratching. Systemic administration of ALLO elicited robust scratching in the atopic dermatitis model, while it did not affect spontaneous and pruritogen-induced scratching in normal mice. ALLO caused scratching when administered intracisternally, but not when administered intrathecally or intradermally, suggesting the involvement of supraspinal mechanisms. Pharmacological analyses suggested that both γ-aminobutyric acid type A receptor activation and serotonin type 3 receptor inhibition were involved in ALLO-induced scratching. We next examined whether endogenously produced ALLO is involved in ethanol-induced scratching in atopic dermatitis mice, because ethanol administration increases ALLO in rodent brain. Acute ethanol administration increased brain ALLO levels, which coincided with increased scratching. Pre-treatment with finasteride, a synthetic ALLO inhibitor, suppressed ethanol-induced scratching and ALLO production in the brain. Collectively, our results demonstrated for the first time that ALLO administration caused marked scratching in atopic dermatitis mice, and ethanol-induced scratching may be mediated through endogenously produced brain ALLO.


Subject(s)
Dermatitis, Atopic/physiopathology , Pregnanolone/metabolism , Pruritus/physiopathology , Animals , Behavior, Animal/physiology , Brain/metabolism , Dermatitis, Atopic/metabolism , Diet , Disease Models, Animal , Eczema , Grooming/physiology , Male , Mice , Pruritus/chemically induced
6.
J Pharmacol Exp Ther ; 368(2): 246-254, 2019 02.
Article in English | MEDLINE | ID: mdl-30523061

ABSTRACT

Activation of transient receptor potential melastatin 2 (TRPM2), an oxidative stress-sensitive Ca2+-permeable channel, contributes to the aggravation of cerebral ischemia-reperfusion (CIR) injury. Recent studies indicated that treatment with the antidepressant duloxetine for 24 hours (long term) attenuates TRPM2 activation in response to oxidative stress in neuronal cells. To examine the direct effects of antidepressants on TRPM2 activation, we examined their short-term (0-30 minutes) treatment effects on H2O2-induced TRPM2 activation in TRPM2-expressing human embryonic kidney 293 cells using the Ca2+ indicator fura-2. Duloxetine exerted the strongest inhibitory effects on TRPM2 activation among the seven antidepressants tested. These inhibitory effects appeared to be due to the inhibition of H2O2-induced TRPM2 activation via an open-channel blocking-like mechanism, because duloxetine reduced the sustained phase but not the initial phase of increases in intracellular Ca2+ concentrations. In a whole-cell patch-clamp study, duloxetine reduced the TRPM2-mediated inward current during the channel opening state. We also examined the effects of duloxetine in a mouse model of CIR injury. The administration of duloxetine to wild-type mice attenuated CIR injury, similar to that in Trpm2 knockout (KO) mice. The administration of duloxetine did not reduce CIR injury further in Trpm2 KO mice, suggesting that it exerts neuroprotective effects against CIR injury by inhibiting TRPM2 activation. Regarding drug repositioning, duloxetine may be a useful drug in reperfusion therapy for ischemic stroke because it has already been used clinically in therapeutics for several disorders, including depression.


Subject(s)
Brain Ischemia/metabolism , Duloxetine Hydrochloride/therapeutic use , Neuroprotective Agents/therapeutic use , Reperfusion Injury/metabolism , TRPM Cation Channels/antagonists & inhibitors , TRPM Cation Channels/metabolism , Animals , Antidepressive Agents/pharmacology , Antidepressive Agents/therapeutic use , Brain Ischemia/prevention & control , Dose-Response Relationship, Drug , Duloxetine Hydrochloride/pharmacology , HEK293 Cells , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Neuroprotective Agents/pharmacology , Reperfusion Injury/prevention & control
7.
Int J Mol Sci ; 19(3)2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29494506

ABSTRACT

We have previously demonstrated that acacia polyphenol (AP) exerts strong anti-obesity, anti-diabetic, and anti-atopic dermatitis effects. In the present study, we investigated the anti-hypertensive effects of AP. Spontaneously hypertensive rats (SHR) with hypertension and control Wistar Kyoto rats (WKY) were used. WKY and SHR were fed AP-containing food or AP-free food (control group) ad libitum for 4 weeks, and their blood pressures were measured. After AP administration, both systolic and diastolic blood pressures were significantly lower in the SHR group than in the control group. There were no differences in the systolic or diastolic blood pressure of WKY between the AP group and the control group. Angiotensin-converting enzyme (ACE) activity, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression, and superoxide dismutase (SOD) activity in SHR kidneys were not altered by AP administration. Blood SOD activity in SHR was significantly higher in the AP group than in the control group. AP exerts anti-hypertensive effects on hypertension but has almost no effect on normal blood pressure. The anti-hypertensive effects of AP may be related to the anti-oxidative effects of increased blood SOD activity.


Subject(s)
Acacia/chemistry , Antihypertensive Agents/pharmacology , Hypertension/metabolism , Hypertension/physiopathology , Plant Extracts/pharmacology , Polyphenols/pharmacology , Animals , Antihypertensive Agents/chemistry , Blood Pressure/drug effects , Body Weight , Disease Models, Animal , Enzyme Activation/drug effects , Gene Expression Regulation/drug effects , Heart Rate , Hypertension/drug therapy , Kidney/drug effects , Kidney/enzymology , Kidney/metabolism , Male , NADPH Oxidases/genetics , NADPH Oxidases/metabolism , Oxidative Stress/drug effects , Peptidyl-Dipeptidase A/metabolism , Plant Extracts/chemistry , Polyphenols/chemistry , Rats , Rats, Inbred SHR , Superoxide Dismutase/blood , Superoxide Dismutase/metabolism
8.
J Pharmacol Sci ; 134(1): 68-74, 2017 May.
Article in English | MEDLINE | ID: mdl-28532624

ABSTRACT

PURPOSE: TRPM2 is a Ca2+-permeable channel that is activated by H2O2. TRPM2-mediated Ca2+ signaling has been implicated in the aggravation of inflammatory diseases. Therefore, the development of TRPM2 inhibitors to prevent the aggravation of these diseases is expected. We recently reported that some Tyrphostin AG-related compounds inhibited the H2O2-induced activation of TRPM2 by scavenging the intracellular hydroxyl radical. In the present study, we examined the effects of AG-related compounds on H2O2-induced cellular responses in human monocytic U937 cells, which functionally express TRPM2. METHODS: The effects of AG-related compounds on H2O2-induced changes in intracellular Ca2+ concentrations, extracellular signal-regulated kinase (ERK) activation, and CXCL8 secretion were assessed using U937 cells. RESULTS: Ca2+ influxes via TRPM2 in response to H2O2 were blocked by AG-related compounds. AG-related compounds also inhibited the H2O2-induced activation of ERK, and subsequent secretion of CXCL8 mediated by TRPM2-dependent and -independent mechanisms. CONCLUSION: Our results show that AG-related compounds inhibit H2O2-induced CXCL8 secretion following ERK activation, which is mediated by TRPM2-dependent and -independent mechanisms in U937 cells. We previously reported that AG-related compounds blocked H2O2-induced TRPM2 activation by scavenging the hydroxyl radical. The inhibitory effects of AG-related compounds on TRPM2-independent responses may be due to scavenging of the hydroxyl radical.


Subject(s)
Clusterin/metabolism , Hydrogen Peroxide/pharmacology , Interleukin-8/metabolism , TRPM Cation Channels/metabolism , Tyrphostins/pharmacology , Calcium/metabolism , Enzyme Activation , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , Hydrogen Peroxide/metabolism , L-Lactate Dehydrogenase/metabolism , Oxidative Stress , TRPM Cation Channels/chemistry , Tyrphostins/chemistry , U937 Cells
9.
Eur J Pharmacol ; 786: 19-28, 2016 Sep 05.
Article in English | MEDLINE | ID: mdl-27238971

ABSTRACT

Some transient receptor potential (TRP) proteins including TRPA1, TPRM2 and TRPV1 are oxidative stress-sensitive Ca(2+)-permeable channels. Ca(2+) signaling via these TRP channels activated by oxidative stress has been implicated in the aggravation of various inflammatory diseases and pain sensation. We recently reported that Tyrphostin AG490 exerted inhibitory effects on H2O2-induced TRPM2 activation by scavenging the hydroxyl radical. In order to identify stronger inhibitors of oxidative stress-sensitive TRP channels than AG490, we examined the inhibitory effects of Tyrphostin AG-related compounds on H2O2-induced TRP channel activation in human embryonic kidney 293 cells expressing TRP channels. AG555 and AG556 blocked the activation of TRPM2 by H2O2 more strongly than AG490. Regarding TRPV1 and TRPA1, none of the three compounds tested affected H2O2-induced TRPV1 activation; however, AG555 and AG556 reduced H2O2-induced TRPA1 activation more than AG490. Thus, we herein identified AG555 and AG556 as new compounds that exert stronger inhibitory effects on H2O2-induced TRPM2 and TRPA1 activation than AG490. Edaravone, a hydroxyl radical scavenger used in the treatment of cerebral hemorrhage and cerebral infarction, did not affect H2O2-induced TRPM2 or TRPA1 activation. AG555 and AG556 may be useful seed compounds as therapeutic agents for several TRP-related diseases associated with oxidative stress.


Subject(s)
Oxidative Stress/drug effects , Transient Receptor Potential Channels/metabolism , Tyrphostins/chemistry , Tyrphostins/pharmacology , Calcium/metabolism , HEK293 Cells , Humans , Intracellular Space/drug effects , Intracellular Space/metabolism
10.
Free Radic Biol Med ; 90: 101-13, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26600069

ABSTRACT

Lung inflammation is a major adverse effect of therapy with the antitumor drug bleomycin (BLM). Transient receptor potential melastatin 2 (TRPM2) is a Ca(2+)-permeable channel that is activated by oxidative stress through the production of ADP-ribose. We herein investigated whether TRPM2 channels contributed to BLM-induced lung inflammation. The intratracheal instillation of BLM into wild-type (WT) mice increased the number of polymorphonuclear leukocytes (PMNs) and inflammatory cytokine levels in the lung. Increases in inflammatory markers in WT mice were markedly reduced in trpm2 knockout (KO) mice, which demonstrated that the activation of TRPM2 channels was involved in BLM-induced lung inflammation. The expression of TRPM2 mRNA was observed in alveolar macrophages, alveolar epithelial cells, and lung fibroblasts. Actually, TRPM2 protein was expressed in lung tissues. Of these, TRPM2 channels in epithelial cells were activated by the addition of H2O2 following a BLM pretreatment, resulting in the secretion of macrophage inflammatory protein-2 (MIP-2). The H2O2-induced activation of TRPM2 by the BLM pretreatment was blocked by the poly(ADP-ribose) polymerase (PARP) inhibitors PJ34 and 3-aminobenzamide. The accumulation of poly(ADP-ribose) in the nucleus, a marker for ADP-ribose production, was strongly induced by H2O2 following the BLM pretreatment. Furthermore, administration of PRAP inhibitors into WT mice markedly reduced recruitment of inflammatory cells and MIP-2 secretion induced by BLM instillation. These results suggest that the induction of MIP-2 secretion through the activation of TRPM2 channels in alveolar epithelial cells is an important mechanism in BLM-induced lung inflammation, and the TRPM2 activation is likely to be mediated by ADP-ribose production via PARP pathway. TRPM2 channels may be new therapeutic target for BLM-induced lung inflammation.


Subject(s)
Antibiotics, Antineoplastic/toxicity , Bleomycin/toxicity , Pneumonia/chemically induced , Pulmonary Alveoli/physiology , TRPM Cation Channels/physiology , Animals , Cytokines/biosynthesis , Epithelial Cells/physiology , Hydrogen Peroxide/pharmacology , Lipopolysaccharides/toxicity , Male , Mice , Mice, Inbred C57BL , Neutrophils/immunology , Poly (ADP-Ribose) Polymerase-1 , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Poly(ADP-ribose) Polymerases/physiology , TRPM Cation Channels/analysis , TRPM Cation Channels/genetics
11.
Int J Biochem Cell Biol ; 68: 119-27, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26386353

ABSTRACT

Transient receptor potential melastatin 2 (TRPM2) is an oxidative stress-sensitive Ca(2+)-permeable channel. In monocytes/macrophages, H2O2-induced TRPM2 activation causes cell death and/or production of chemokines that aggravate inflammatory diseases. However, relatively high concentrations of H2O2 are required for activation of TRPM2 channels in vitro. Thus, in the present study, factors that sensitize TRPM2 channels to H2O2 were identified and subsequent physiological responses were examined in U937 human monocytes. Temperature increase from 30°C to 37°C enhanced H2O2-induced TRPM2-mediated increase in intracellular free Ca(2+) ([Ca(2+)]i) in TRPM2-expressing HEK 293 cells (TRPM2/HEK cells). The H2O2-induced TRPM2 activation enhanced by the higher temperature was dramatically sensitized by intracellular Fe(2+)-accumulation following pretreatment with FeSO4. Thus intracellular Fe(2+)-accumulation sensitizes H2O2-induced TRPM2 activation at around body temperature. Moreover, intracellular Fe(2+)-accumulation increased poly(ADP-ribose) levels in nuclei by H2O2 treatment, and the sensitization of H2O2-induced TRPM2 activation were almost completely blocked by poly(ADP-ribose) polymerase inhibitors, suggesting that intracellular Fe(2+)-accumulation enhances H2O2-induced TRPM2 activation by increase of ADP-ribose production through poly(ADP-ribose) polymerase pathway. Similarly, pretreatment with FeSO4 stimulated H2O2-induced TRPM2 activation at 37°C in U937 cells and enhanced H2O2-induced ERK phosphorylation and interleukin-8 (CXCL8) production. Although the addition of H2O2 to cells under conditions of intracellular Fe(2+)-accumulation caused cell death, concentration of H2O2 required for CXCL8 production was lower than that resulting in cell death. These results indicate that intracellular Fe(2+)-accumulation sensitizes TRPM2 channels to H2O2 and subsequently produces CXCL8 at around body temperature. It is possible that sensitization of H2O2-induced TRPM2 channels by Fe(2+) may implicated in hemorrhagic brain injury via aggravation of inflammation, since Fe(2+) is released by heme degradation under intracerebral hemorrhage.


Subject(s)
Hydrogen Peroxide/pharmacology , Interleukin-8/biosynthesis , Iron/metabolism , Macrophages, Peritoneal/metabolism , Monocytes/metabolism , TRPM Cation Channels/genetics , Animals , Calcium/metabolism , Cations, Divalent , Cell Line , Ferrous Compounds/pharmacology , Gene Expression Regulation , HEK293 Cells , Humans , Interleukin-8/genetics , Ion Transport , Macrophages, Peritoneal/cytology , Macrophages, Peritoneal/drug effects , Mice , Mice, Knockout , Mitogen-Activated Protein Kinase 1/genetics , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/genetics , Mitogen-Activated Protein Kinase 3/metabolism , Monocytes/cytology , Monocytes/drug effects , Oxidative Stress/drug effects , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Poly(ADP-ribose) Polymerases/genetics , Poly(ADP-ribose) Polymerases/metabolism , Primary Cell Culture , Signal Transduction , TRPM Cation Channels/agonists , TRPM Cation Channels/metabolism , Temperature
12.
J Pharm Pharmacol ; 67(12): 1716-22, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26246025

ABSTRACT

OBJECTIVES: We attempted to ascertain if bisbenzylisoquinoline alkaloids, liensinine and isoliensinine from Nelumbo nucifera Gaertner have antidepressant-like effects and compare the effects with those previously obtained by their analogue neferine. METHODS: Using mice, the forced swimming test (FST) was carried out after treatment with liensinine, isoliensinine and neferine. KEY FINDINGS: Liensinine and isoliensinine elicited antidepressant-like effects in mice after the FST. Anti-immobility effects of liensinine and isoliensinine were antagonized by the 5-hydroxytryptamine1 A (5-HT1 A ) receptor antagonist WAY 100635, but not by the α1 -adrenoceptor antagonist prazosin. The anti-immobility effects of liensinine, isoliensinine and neferine were blocked by pretreatment with p-chlorophenylalanine (PCPA), which depletes serotonin (5-HT). CONCLUSIONS: These data suggest that liensinine and isoliensinine from Nelumbo nucifera Gaertner have antidepressant-like effects and that antidepressant-like effects of liensinine and its analogues are closely related to serotonergic mechanisms.


Subject(s)
Antidepressive Agents/pharmacology , Behavior, Animal/drug effects , Benzylisoquinolines/pharmacology , Isoquinolines/pharmacology , Nelumbo/chemistry , Phenols/pharmacology , Plant Extracts/pharmacology , Serotonin Agents/pharmacology , Stress, Psychological/drug therapy , Animals , Antidepressive Agents/isolation & purification , Benzylisoquinolines/isolation & purification , Disease Models, Animal , Dose-Response Relationship, Drug , Isoquinolines/isolation & purification , Male , Mice, Inbred ICR , Motor Activity/drug effects , Nelumbo/embryology , Phenols/isolation & purification , Phytotherapy , Plant Extracts/isolation & purification , Plants, Medicinal , Seeds , Serotonergic Neurons/drug effects , Serotonergic Neurons/metabolism , Serotonin Agents/isolation & purification , Stress, Psychological/metabolism , Stress, Psychological/psychology , Swimming
13.
Biol Pharm Bull ; 38(5): 740-5, 2015.
Article in English | MEDLINE | ID: mdl-25740003

ABSTRACT

Comparative studies of the potency of long- and short-acting erythropoiesis-stimulating agents (L-ESAs and S-ESAs) on erythropoietic activity in patients with chronic kidney disease without dialysis have not been performed, although L-ESAs are used in many countries. We performed a retrospective analysis of non-dialysis (ND) patients who had received L-ESA or S-ESA. More days were needed for the S-ESA-treated group (368 d) to reach the haemoglobin (Hb) reference range than for the L-ESA-treated group (126 d). Therefore, we investigated risk factors that influence the period until the Hb level reaches the reference range. Patients were classified into two groups by the period until the Hb level was stabilised within the reference range: the short- and long-term group. Two risk factors for delayed Hb stabilisation were identified: age ≥60 years; and administration of an S-ESA for initial treatment. These findings suggest that the Hb level should be carefully monitored during ESA therapy in elderly ND patients, and that the ESA dose should be increased or L-ESA therapy should be utilised to treat renal anaemia.


Subject(s)
Anemia/prevention & control , Erythropoiesis/drug effects , Erythropoietin/blood , Hematinics/therapeutic use , Hemoglobins/metabolism , Renal Insufficiency, Chronic/complications , Age Factors , Aged , Aged, 80 and over , Anemia/blood , Female , Hematinics/pharmacology , Humans , Immunotherapy, Adoptive , Male , Middle Aged , Renal Dialysis , Renal Insufficiency, Chronic/blood , Retrospective Studies , Time Factors
14.
Eur J Pharmacol ; 742: 22-30, 2014 Nov 05.
Article in English | MEDLINE | ID: mdl-25179574

ABSTRACT

Transient receptor potential melastatin 2 (TRPM2) is an oxidative stress-sensitive Ca(2+)-permeable channel that controls Ca(2+) signalling. The activation of Janus kinase 2 (Jak2) by oxidative stress is implicated in the production of inflammatory mediators. We found that AG490, a Jak2 inhibitor, had an inhibitory effect on H2O2-induced TRPM2 activation. The purpose of this study was to examine the underlying mechanisms of the inhibitory effects of AG490. Activation of TRPM2 in TRPM2-expressing human embryonic kidney 293 (TRPM2/HEK) cells or the human monocytic cell line U937 was monitored by fluorescence-based Ca(2+) imaging and patch-clamp techniques. Treatment with AG490 almost completely blocked H2O2-induced increase in intracellular Ca(2+) in TRPM2/HEK and U937 cells. In the patch-clamp study, AG490 inhibited the H2O2-evoked inward current but not the ADP-ribose-induced inward current in TRPM2/HEK cells. In contrast, Jak inhibitor 1 (pyridone 6) and staurosporine, both of which inhibit Jak2, had no effect on H2O2-induced increase in intracellular Ca(2+). Moreover, AG490 decreased intracellular reactive oxygen species level, which was measured by using a hydroperoxide-sensitive fluorescent dye, on incubation with H2O2. In the cell-free assay system, AG490 scavenged hydroxyl radicals but not H2O2. These findings indicate that AG490 significantly reduces H2O2-induced TRPM2 activation, presumably by scavenging hydroxyl radicals rather than Jak2-dependent mechanisms. Although transient receptor potential ankyrin 1 (TRPA1) channel is also activated by H2O2, the H2O2-induced Ca(2+) entry through TRPA1 was only slightly delayed by AG490. This validates the potential use of AG490, as one of the materials for characterizing the role of TRPM2 channels in pathological models.


Subject(s)
Calcium Signaling/drug effects , Hydrogen Peroxide/toxicity , TRPM Cation Channels/metabolism , Tyrphostins/pharmacology , Benzimidazoles/pharmacology , Calcium Channels/metabolism , Enzyme Inhibitors/pharmacology , Free Radical Scavengers/pharmacology , HEK293 Cells , Humans , Janus Kinase 1/antagonists & inhibitors , Janus Kinase 2/antagonists & inhibitors , Janus Kinase 2/metabolism , Nerve Tissue Proteins/metabolism , Oxidative Stress/drug effects , Patch-Clamp Techniques , Poly(ADP-ribose) Polymerase Inhibitors , Poly(ADP-ribose) Polymerases/metabolism , Pyridones/pharmacology , Reactive Oxygen Species/metabolism , Recombinant Proteins/metabolism , Staurosporine/pharmacology , TRPA1 Cation Channel , TRPM Cation Channels/agonists , TRPM Cation Channels/antagonists & inhibitors , Transient Receptor Potential Channels/metabolism , U937 Cells
15.
Biol Pharm Bull ; 37(2): 298-305, 2014.
Article in English | MEDLINE | ID: mdl-24270587

ABSTRACT

We had previously revealed that drug metabolism, as well as the expression level of hepatic CYP3A, a drug-metabolizing enzyme, increase 12 weeks after gastrectomy in mice. In this study, we elucidated the mechanism of the increased CYP3A expression. The levels of lithocholic acid (LCA)-producing bacteria (Bacteroides fragilis) and LCA in the colon did not show a significant increase up to 4 weeks after gastrectomy compared to the sham operation group. In contrast, at 12 and 24 weeks post-gastrectomy, the levels of Bacteroides fragilis and LCA were significantly higher in the gastrectomy group than in the sham operation group. At 12 and 24 weeks after gastrectomy, the hepatic nuclear translocation of pregnane X receptor (PXR) had also increased. The hepatic CYP3A11 mRNA expression and nuclear translocation of PXR after intraperitoneal administration of LCA to normal mice was significantly higher than those of the control group. The intraperitoneal administration of taurolithocholic acid (TLCA), a taurine conjugate of LCA, caused no change in the expression level of CYP3A11. We suggest that the increase in the expression level of CYP3A after gastrectomy is caused by an increase in the nuclear translocation of PXR, which is triggered by an increase in LCA-producing bacteria.


Subject(s)
Bacteroides fragilis/metabolism , Colon/microbiology , Cytochrome P-450 CYP3A/metabolism , Enterobacteriaceae/metabolism , Gastrectomy , Lithocholic Acid/metabolism , Liver/metabolism , Animals , Biological Transport , Colon/metabolism , Cytochrome P-450 CYP3A/genetics , Inactivation, Metabolic , Male , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Mice, Inbred ICR , Pregnane X Receptor , RNA, Messenger/metabolism , Receptors, Steroid/metabolism
16.
Eur J Pharm Sci ; 51: 180-8, 2014 Jan 23.
Article in English | MEDLINE | ID: mdl-24095864

ABSTRACT

In patients with gastrectomy, it is possible that drug effectiveness is reduced compared to healthy subjects due to the increased of the drug-metabolizing enzyme, Cytochrome P450 (CYP). The purpose of this study is to verify this possibility. Gastrectomy model mice were prepared to evaluate the expression level of various CYPs in the liver from 2 to 24 weeks post-operation. No significant differences were observed in the protein expression levels of CYP3A, CYP1A, CYP2C, and CYP2D between the sham operation group and the gastrectomy group up to 4 weeks after the gastrectomy. On the other hand, significant increases in the protein expression levels of any CYPs were observed in the gastrectomy group compared to the sham operation group from 12 weeks after the gastrectomy onward. These increases in expression levels were maintained until 24 weeks after the gastrectomy. The examination of metabolic activity in the liver in the gastrectomy group using triazolam revealed that the metabolic activity at 12 weeks after the gastrectomy was significantly increased in the gastrectomy group. The administration of the anticancer drug imatinib, which is a substrate of CYP3A, to mice at 12weeks after gastrectomy resulted in an increase in the metabolic rate, suggesting a possible decrease in drug effectiveness. It has been revealed that drug effectiveness may be reduced after gastrectomy because the expression levels of various CYPs in the liver were increased over a prolonged period. The results of this study can serve as valuable fundamental knowledge for drug therapy in patients with gastrectomy.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Gastrectomy/adverse effects , Liver/enzymology , Liver/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Animals , Basal Metabolism/drug effects , Basal Metabolism/physiology , Benzamides/pharmacology , Body Weight/drug effects , Body Weight/genetics , Eating/drug effects , Eating/physiology , Imatinib Mesylate , Intestine, Large/drug effects , Intestine, Large/enzymology , Intestine, Large/metabolism , Intestine, Small/drug effects , Intestine, Small/enzymology , Intestine, Small/metabolism , Liver/drug effects , Male , Mice , Mice, Inbred ICR , Microsomes, Liver/drug effects , Microsomes, Liver/enzymology , Microsomes, Liver/metabolism , Piperazines/pharmacology , Pyrimidines/pharmacology , Triazolam/metabolism
17.
PLoS One ; 8(9): e75445, 2013.
Article in English | MEDLINE | ID: mdl-24066181

ABSTRACT

Firefly luciferase (Luc) is widely used as a reporter enzyme in cell-based assays for gene expression. A novel aromatic carboxylic acid, F-53, reported here for the first time, substantially inhibited the enzymatic activity of Luc in a Luc reporter screening. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and tandem mass spectrometry (MS/MS) analyses showed that F-53 modifies Luc at lysine-529 via amidation of the F-53 carboxyl group. The lysine-529 residue of Luc, which plays a regulatory catalytic role, can be acetylated. Luc also has a long-chain fatty acyl-CoA synthase activity. An in vitro assay that involved both recombinant Luc and mouse liver microsomes identified F-53-CoA as the reactive form produced from F-53. However, whereas the inhibitory effect of F-53 is observed in Hela cells that transiently expressed Luc, it is not observed in an in vitro assay that involves recombinant Luc alone. Therefore, insights into the activities of certain mammalian transferases can be translated to better understand the acylation by F-53. The insights from this study about the novel inhibitory modification mechanism might help not only to avoid misinterpretation of the results of Luc-based reporter screening assays but also to explain the pharmacological and toxicological effects of carboxylic acid-containing drugs.


Subject(s)
Carboxylic Acids/pharmacology , Luciferases/metabolism , Acylation/drug effects , Animals , COS Cells , Cell Line , Humans , Luciferases/chemistry , Lysine/metabolism , Mice , Reverse Transcriptase Polymerase Chain Reaction
18.
Chem Pharm Bull (Tokyo) ; 61(8): 846-52, 2013.
Article in English | MEDLINE | ID: mdl-23902867

ABSTRACT

Compound 1 (IT-M-07000) was previously reported as a candidate prodrug of Am80 (Tamibarotene; used to treat acute promyelocytic leukemia), and shown to be efficiently metabolized to Am80 via ß-oxidation. Here, we describe in detail the synthesis of 1, together with another tetradeuterated candidate prodrug, IT-YA-00616 (2), as well as two congeners, and several metabolic intermediates of 1 previously detected in mouse plasma.


Subject(s)
Benzoates/metabolism , Phenylpropionates/chemical synthesis , Prodrugs/chemical synthesis , Receptors, Retinoic Acid/agonists , Tetrahydronaphthalenes/chemical synthesis , Tetrahydronaphthalenes/metabolism , Humans , Leukemia, Promyelocytic, Acute/drug therapy , Oxidation-Reduction , Phenylpropionates/metabolism , Prodrugs/metabolism
19.
BMC Res Notes ; 6: 198, 2013 May 20.
Article in English | MEDLINE | ID: mdl-23687997

ABSTRACT

BACKGROUND: Thyroid storm is a serious condition of thyrotoxicosis. Hyperthyroidism often presents with thrombotic events, especially at cerebral sites; however, the possible association between a lower extremity deep vein thrombosis (LEDVT) and thyroid storm has not been previously reported. We encountered a patient who developed thyroid storm, associated with rhabdomyolysis, followed by LEDVT and a small silent pulmonary embolism (PE). The case is discussed with references to the pertinent literature. CASE PRESENTATION: A 50-year-old woman with no past medical history was referred to our hospital because of severe diarrhea, muscle weakness in her lower limbs (manual muscle testing: MMT 3), and disturbances of consciousness. She was diagnosed as having Graves' disease based on the presence of struma, exophthalmos, and hyperthyroidism with TSH receptor antibody positivity; we further determined that the patient was experiencing thyroid storm based on the results of the Burch-Wartofsky scoring system and a Japanese diagnostic criteria. Treatment with steroids, iodine potassium, methimazole, and propranolol was initiated. Severe watery diarrhea continued, and the laboratory data revealed hypokalemia (2.0 meq/L). On day 14, a blood analysis showed a sudden elevation in her creatinine kinase (CK) level, leading to a diagnosis of rhabdomyolysis. Thereafter, the muscle weakness in her lower limbs advanced to a degree of MMT 1. Seven days after the diagnosis of rhabdomyolysis, pitting edema began to appear in bilateral lower extremities. Contrast-enhanced CT scans revealed a LEDVT involving the left common iliac vein, bilateral femoral veins, and left popliteal vein. Furthermore, a small PE was identified. Hyperthyroidism often presents with thrombotic events, especially at cerebral sites, but few reports of PE or LEDVT have been made. CONCLUSION: This case suggests that the occurrence of thyroid storm may be associated with a risk of LEDVT and/or PE. We suggest that DVT preventive measures are undertaken, and that a lower limb venous echo or contrast-enhanced CT examination would be considered if LEDVT is suspected.


Subject(s)
Pulmonary Embolism/complications , Rhabdomyolysis/complications , Thyroid Crisis/complications , Venous Thrombosis/complications , Female , Humans , Middle Aged
20.
Biol Pharm Bull ; 36(4): 624-34, 2013.
Article in English | MEDLINE | ID: mdl-23370405

ABSTRACT

Changes in the expression level and activity of cytochrome P450 (CYP) in the liver are caused by various factors and affect the pharmacokinetics of drugs. The purpose of this study was to determine whether the expression of CYP3A is affected by a high-fat diet. In addition, we examined whether the type of diet given to mice could produce changes in the expression level and activity of CYP3A. Mice were fed a purified diet containing 10 kcal% lard (control group) or 60 kcal% lard (HF group) or regular mouse chow containing 13 kcal% of fat (MF group) for 4 weeks. No significant differences were observed in the hepatic CYP3A protein expression level between the HF group and the control group. The CYP3A protein expression in the MF group was significantly higher than that observed in the control group. In the MF group, the area under the curve (AUC) of intraperitoneally administered triazolam was lower. Because lithocholic acid (LCA) is known to increase hepatic CYP3A expression, the levels of Clostridium sordellii and LCA in the feces were measured. In the MF group, the levels of Clostridium sordellii and LCA were higher. It has been demonstrated that a high-fat diet does not cause any changes in hepatic CYP3A expression. In addition, the different diets caused alterations in the enteric environment, which triggered changes in CYP3A expression. Therefore, it is necessary to carefully consider the type of feed while performing animal experiments to evaluate the pharmacokinetics of drugs.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Diet, High-Fat , Liver/metabolism , Adipose Tissue, White/growth & development , Animals , Blood Glucose/analysis , Body Weight , Cholesterol/blood , Cytochrome P-450 CYP3A/genetics , Fatty Acids, Nonesterified/blood , Feces/chemistry , Lithocholic Acid/metabolism , Liver/growth & development , Male , Membrane Proteins/genetics , Mice , Mice, Inbred ICR , Microsomes/metabolism , Organ Size , RNA, Messenger/metabolism , Triazolam/pharmacokinetics , Triglycerides/blood
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