Journal of Pharmacological Sciences
Online ISSN : 1347-8648
Print ISSN : 1347-8613
ISSN-L : 1347-8613
Volume 124 , Issue 2
Showing 1-18 articles out of 18 articles from the selected issue
Current Perspective
  • Makoto Yoshida, Shigeyoshi Honma
    2014 Volume 124 Issue 2 Pages 117-122
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 25, 2014
    JOURNALS FREE ACCESS
    Acute kidney injury (AKI), clinically defined by high serum creatinine and low urine flow, has many complicated pathophysiological features including tubular and glomerular injury. Although renal tubules are thought to be constituted by highly differentiated epithelial cells, it is possible to repair injured nephrons by the healing process. Several studies have revealed that AKI, especially AKI caused by ischemia/reperfusion injury or nephrotoxic medication, depends on a number of factors, including activation of transcriptional factors, endothelial injury of peritubular small vessels, immune responses, and inflammatory processes associated with necrosis and apoptosis of renal tubular epithelium. For regeneration of injured tubules, partly dedifferentiated progenitor-like cells fill the injured site and constitute the tubular structure and function, although the source of these cells is still under debate. It is essential to understand the molecular, cellular, and genetic mechanisms of AKI and tubular regeneration for the development of therapies to prevent and treat kidney injury.
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  • Nobuyuki Yanagihara, Han Zhang, Yumiko Toyohira, Keita Takahashi, Susu ...
    2014 Volume 124 Issue 2 Pages 123-128
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 31, 2014
    JOURNALS FREE ACCESS
    Flavonoids are biologically active polyphenolic compounds widely distributed in plants. Recent research has focused on high dietary intake of flavonoids because of their potential to reduce the risks of diseases such as cardiovascular diseases, diabetes, and cancers. We report here the effects of plant flavonoids on catecholamine signaling in cultured bovine adrenal medullary cells used as a model of central and peripheral sympathetic neurons. Daidzein (0.01 – 1.0 μM), a soy isoflavone, stimulated 14C-catecholamine synthesis through plasma membrane estrogen receptors. Nobiletin (1.0 – 100 μM), a citrus polymethoxy flavone, enhanced 14C-catecholamine synthesis through the phosphorylation of Ser19 and Ser40 of tyrosine hydroxylase, which was associated with 45Ca2+ influx and catecholamine secretion. Treatment with genistein (0.01 – 10 μM), another isoflavone, but not daidzein, enhanced [3H]noradrenaline uptake by SK-N-SH cells, a human noradrenergic neuroblastoma cell line. Daidzein as well as nobiletin (≥ 1.0 μM) inhibited catecholamine synthesis and secretion induced by acetylcholine, a physiological secretagogue. The present review shows that plant flavonoids have various pharmacological potentials on the catecholamine system in adrenal medullary cells, and probably also in sympathetic neurons.
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Critical Review
  • Ken-Ichi Furukawa
    2014 Volume 124 Issue 2 Pages 129-137
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 25, 2014
    JOURNALS FREE ACCESS
    Aortic valve calcification can aggravate aortic stenoses, and it is a significant cause of sudden cardiac death. The increasing number of patients with age-related calcification is a problem in developed nations. However, the only treatment option currently available is highly invasive cardiac valve replacement. Therefore, clarification of the etiology of calcification is urgently needed to develop drug therapies and prevention methods. Recent studies have revealed that calcification is not a simple sedimentation of a mineral through a physicochemical phenomenon; various factors dynamically contribute to the mechanism. Further, we are finally beginning to understand the cellular origins of calcification, which had been unclear for a long time. Based on these findings that help to clarify potential drug targets, we expect to establish drug therapies that reduce the stress on patients. In this paper, I introduce the latest findings on cells that are most likely to contribute to calcification and on calcification-related factors that may lead to the development of drug therapies.
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Full Paper
  • Katarina Vučićević, Zorica Rakonjac, Branislava Miljković, Borisav Jan ...
    2014 Volume 124 Issue 2 Pages 138-143
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 18, 2014
    JOURNALS FREE ACCESS
    The purpose of the study was to compare peak (Cpeak) and trough (Ctrough) amikacin levels after twice-daily (TD) or once-daily dosing (OD) in full-term neonates. Additionally, the study aimed to address amikacin pharmacokinetics and its variability. Data included 31 patients born on term. Amikacin daily dose was 15 or 20 mg/kg depending on the neonate’s age. Patients randomly received amikacin every 12 or 24 h. In all patients corresponding Cpeak and Ctrough were taken. Volume of distribution (Vd), clearance (CL) and half-life (t1/2) were calculated. Mean Cpeak of 21.79 μg/ml in the TD group was statistically different from Cpeak of 36.39 μg/ml in the OD group. Average Ctrough in TD (5.67 μg/ml) was statistically different from the corresponding 3.99 μg/ml in the OD group. Mean amikacin Vd, CL, and t1/2 were 0.78 ± 0.38 l/kg, 86.99 ± 48.22 ml/h∙kg, and 6.81 ± 2.51 h, respectively. High interindividual pharmacokinetic variability was observed. Further analysis showed that neonatal age contributed to the pharmacokinetic parameters’ values. Statistically significant difference in CL and t1/2 was observed between patients age ≤ 2 and > 2 days on therapy initiation. As expected, amikacin given OD achieved higher Cpeak and lower Ctrough than TD. Based on the results, observed variability in amikacin pharmacokinetics was possibly due to the renal maturation process.
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  • Evangelos J. Giamarellos-Bourboulis, Aikaterini Spyridaki, Athina Savv ...
    2014 Volume 124 Issue 2 Pages 144-152
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 30, 2014
    JOURNALS FREE ACCESS
    One prospective, open-label, non-randomized study was conducted in 100 patients to define the antipyretic and analgesic effect of a new intravenous formulation of 1 g of paracetamol; 71 received paracetamol for the management of fever and 29 received paracetamol for pain relief after abdominal surgery or for neoplastic pain. Serial follow-up measurements of core temperature and of pain intensity were done for 6 h. Additional rescue medications were recorded for 5 days. Blood was sampled for the measurement of free paracetamol (APAP) and of glucuronide-APAP and N-sulfate-APAP by an HPLC assay. Defervescence, defined as core temperature below or equal to 37.1°C, was achieved in 52 patients (73.2%) within a median time of 3 h. Patients failing to become afebrile with the first dose of paracetamol became afebrile when administered other agents as rescue medications. Analgesia was achieved in 25 patients (86.4%) within a median time of 2 h. Serum levels of glucuronide-APAP were greater among non-responders to paracetamol. The presented results suggest that the intravenous formulation of paracetamol is clinically effective depending on drug metabolism.
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  • Katsuyuki Kazusa, Yuji Nakamura, Yudai Watanabe, Kentaro Ando, Atsushi ...
    2014 Volume 124 Issue 2 Pages 153-159
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 23, 2014
    JOURNALS FREE ACCESS
    Since information regarding the effects of pH on the extent of nifekalant-induced repolarization delay and torsades de pointes remains limited, we assessed it with a Langendorff heart model of guinea pigs. First, we investigated the effects of pH change from 7.4 to 6.4 on the bipolar electrogram simulating surface lead II ECG, monophasic action potential (MAP), effective refractory period (ERP), and terminal repolarization period (TRP) and found that acidic condition transiently enhanced the ventricular repolarization. Next, we investigated the effects of pH change from 6.4 to 7.4 in the presence of nifekalant (10 μM) on the ECG, MAP, ERP, TRP, and short-term variability (STV) of MAP90 and found that the normalization of pH prolonged the MAP90 and ERP while the TRP remained unchanged, suggesting the increase in electrical vulnerability of the ventricle. Meanwhile, the STV of MAP90 was the largest at pH 6.4 in the presence of nifekalant, indicating the increase in temporal dispersion of repolarization, which gradually decreased with the return of pH to 7.4.Thus, a recovery period from acidosis might be more dangerous than during the acidosis, because electrical vulnerability may significantly increase for this period while temporal dispersion of repolarization remained increased.
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  • Yoshihiro Uesawa, Shigeru Hishinuma, Masaru Shoji
    2014 Volume 124 Issue 2 Pages 160-168
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 29, 2014
    JOURNALS FREE ACCESS
    There is argument whether non-sedative properties of histamine H1–receptor antagonists (antihistamines) are determined by their active extrusions from the brain via P-glycoprotein or their restricted penetration through the blood-brain barrier. We have reported that sedative and non-sedative antihistamines can be well discriminated by measuring changes in their binding to H1 receptors upon receptor internalization in intact cells, which depends on their membrane-penetrating ability. In this study, molecular determinants responsible for sedative and non-sedative properties of antihistamines were evaluated by quantitative structure-activity relationship (QSAR) analyses. Multiple regression analyses were applied to construct a QSAR model, taking internalization-mediated changes in the binding of antihistamines as objective variables and their structural descriptors as explanatory variables. The multiple regression model was successfully constructed with two explanatory variables, i.e., lipophilicity of the compounds at physiological pH (logD) and mean information content on the distance degree equality (IDDE) (r2 = 0.753). The constructed model discriminated between sedative and non-sedative antihistamines with 94% accuracy for external validation. These results suggest that logD and IDDE concerning lipophilicity and molecular shapes of compounds, respectively, predominantly determine the membrane-penetrating ability of antihistamines for their side effects on the central nervous system.
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  • Rui Yang, Heng-Jing Cui, Hua Wang, Yan Wang, Jian-Hua Liu, Yong Li, Ya ...
    2014 Volume 124 Issue 2 Pages 169-179
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 25, 2014
    JOURNALS FREE ACCESS
    N-Stearoyltyrosine (NsTyr), a synthesized anandamide (AEA) analogue, could exert potent neuroprotective effects on cerebral ischemia models both in vivo and in vitro via intervening in multiple injuries. Glutamate, a major excitatory neurotransmitter, plays a critical role during stroke/cerebral ischemia. In this study, we explored the protective effects of NsTyr on glutamate neurotoxicity in PC12 cells and investigated its underlying mechanisms. NsTyr treatment attenuated glutamate-induced oxidative toxicity in a dose-dependent manner and the best performance was observed at 10 μΜ. NsTyr treatment suppressed glutamate-induced upregulation of lipoxygenase 12/15 (LOX 12/15) activity and reactive oxygen species (ROS) elevation, attenuated the increase of BH3-interacting domain death agonist (Bid) in the mitochondria, prevented the loss of mitochondria membrane potential and consequently inhibited apoptosis-inducing factor (AIF) translocation into the nucleus. The results demonstrated that NsTyr could protect cells against AIF-mediated caspase-independent cell death induced by glutamate, which may be due to the blockage of Bid-mediated mitochondrial damage via reducing LOX 12/15 activity and ROS accumulation.
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  • Shoji Kawauchi, Tsutomu Nakamura, Ikuya Miki, Jun Inoue, Tsuneo Hamagu ...
    2014 Volume 124 Issue 2 Pages 180-191
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 31, 2014
    JOURNALS FREE ACCESS
    CYP3A and P-glycoprotein (P-gp) play important roles in drug metabolism and excretion; however, their functions in pathological conditions remain unclear. Hepatobiliary abnormalities have been described in patients with ulcerative colitis, which may affect drug metabolism and excretion in the liver and small intestine. We examined the functions of CYP3A and P-gp in the liver and small intestine of mice with dextran sodium sulfate (DSS)-induced colitis. Up to day 7, inflammatory markers were significantly increased in the livers of DSS-treated mice, accompanied by decreased CYP3A. Additionally hepatobiliary transporters and Pregnane X receptor, which regulates the transcriptional activation of CYP3A, were reduced. Both CYP3A and P-gp were significantly decreased in the upper small intestine of DSS-treated mice on day 7. This was associated with the increased expression of inducible nitric oxide synthase, but not changes in nuclear receptor expression. On day 7 of DSS treatment, the concentrations of cyclosporine A (CsA), a substrate of both CYP3A and P-gp, were significantly higher than controls. These results indicated the existence of a second inflammatory response in the liver and upper small intestine of mice with DSS-induced colitis, and bioavailability of CsA was increased by the dysfunction of CYP3A and P-gp in these organs.
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  • Sachie Sasaki-Hamada, Keita Tamaki, Hayuma Otsuka, Tatsuto Ueno, Hiroa ...
    2014 Volume 124 Issue 2 Pages 192-200
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 29, 2014
    JOURNALS FREE ACCESS
    Childhood-onset type 1 diabetes is associated with modest impairments in cognition and has an elevated risk of cognitive decline. Our previous study showed that working memory and hippocampal long-term depression (LTD) were impaired in juvenile-onset diabetes mellitus (JDM) rats. In this study, we investigated the effect of chotosan (CTS), a traditional herbal formula called a Kampo medicine, which has been clinically demonstrated to be effective for the treatment of vascular dementia, on JDM rats. The repeated treatment with CTS (1 g/kg per day) for 3 – 7 days restored spatial working memory and hippocampal LTD in JDM rats. The expression level of NR2B glutamate receptor subunits, but not other glutamate receptor subunits was enhanced in the hippocampus of JDM rats, and repeated treatment with CTS reversed these changes. These results suggest that CTS improves diabetes-induced cognitive deficits by modulating NMDA-receptor subunit expression.
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  • Nobuo Aikawa, Atsushi Kunisato, Kenji Nagao, Hideaki Kusaka, Katsumi T ...
    2014 Volume 124 Issue 2 Pages 201-207
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 23, 2014
    JOURNALS FREE ACCESS
    The mouse embryonic stem cell test (mEST) is used to assess the embryotoxicity of drug candidates by evaluating the effects on the cardiac differentiation of stem cells. However, thalidomide embryotoxicity has not yet been reported using the mEST. To detect the effects of thalidomide, we used human induced pluripotent stem cells (hiPSCs) instead of mouse embryonic stem cells, and assessed three endpoints: the inhibition of cardiac differentiation, the cytotoxicity to hiPSCs, and the cytotoxicity to human dermal fibroblasts, according to the mEST. From these data (IC50 values), the embryotoxicity was classified into one of three different classes based on the mEST and our criteria. Valproate was used as a positive control and ascorbic acid was used as a negative control, and their effects were assessed. Similar to valproate, thalidomide was classified as a Class 2 agent, with weak embryotoxicity, by the mEST criteria, and was classified as Category 3 embryotoxic based on our criteria. Ascorbic acid was classified as a Class 1 / Category 1, non-embryotoxic agent, based on both criteria. Thalidomide embryotoxicity was detected in the embryonic stem cell test based on hiPSCs. This test system is thus considered to have a much greater predictive ability than the mEST.
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  • Dae-Woong Yun, Seul Ah Lee, Min-Gyeong Park, Jae-Sung Kim, Sun-Kyoung ...
    2014 Volume 124 Issue 2 Pages 208-217
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: February 04, 2014
    JOURNALS FREE ACCESS
    Compared to most normal cells that express L-type amino acid transporter 2, L-type amino acid transporter 1 is highly expressed in cancer cells and presumed to support their elevated growth and proliferation. This study examined JPH203, a potent and selective L-type amino acid transporter 1 inhibitor, and its ability to suppress YD-38 human oral cancer cell growth. The YD-38 cells express L-type amino acid transporter 1 with its associating protein 4F2 heavy chain, but not L-type amino acid transporter 2. JPH203 and BCH, a non-selective L-type amino acid transporter inhibitor, completely inhibited l-leucine uptake in YD-38 cells. As expected, the intrinsic affinity of JPH203 to inhibit l-leucine uptake was far more efficient than BCH. Likewise, JPH203 and BCH inhibited YD-38 cell growth, with JPH203 being superior to BCH. JPH203 up-regulated the population of apoptotic YD-38 cells through the activation of apoptotic factors, including caspases and PARP. These results suggest that the inhibition of L-type amino acid transporter 1 activity via JPH203, which may act as a potential novel anti–oral-cancer agent, leads to apoptosis by inducing the intracellular depletion of the neutral amino acids essential for cancer cell growth in YD-38 human oral cancer cells.
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  • Kohei Aritomi, Yoichi Ishitsuka, Yoshiro Tomishima, Daisuke Shimizu, N ...
    2014 Volume 124 Issue 2 Pages 218-229
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: February 04, 2014
    JOURNALS FREE ACCESS
    Overdoses of acetaminophen (paracetamol, N-acetyl-p-aminophenol; APAP) cause severe liver injury, yet there is no common or high throughput in vitro human APAP model. This study examined the characteristics and usefulness of HepG2 cells grown in a nano culture plate (NCP) system, a three-dimensional culture method, as an in vitro human model for APAP-induced hepatotoxicity. The NCP-cultured HepG2 cells showed higher expression of mRNA and protein levels of cytochrome P450 2E1, which metabolizes APAP to a toxic metabolite, APAP-cysteine adduct formation, and higher sensitivity against APAP-induced cell injury compared with conventionally cultured cells. We demonstrated that treatment of APAP in NCP-cultured HepG2 cells shows key mechanistic features of APAP-induced hepatotoxicity, such as decreases in intracellular glutathione and mitochondrial membrane potential, activation of JNK, and cellular injury; and pharmacological agents, such as Cyclosporine A (a mitochondrial permeability transition inhibitor) and SP600125 (a JNK inhibitor), prevented cell injury induced by APAP exposure. In addition, the antidote of APAP-induced hepatotoxicity, N-acetylcysteine, could attenuate cellular injury induced by APAP in NCP-cultured HepG2 cells. We suggest that cellular injury induced by APAP treatment using an NCP-HepG2 system is a useful human model to study mechanisms and screen drug candidates of APAP-induced hepatotoxicity.
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  • Shozaburo Hata, Kazuhiko Okamura, Mitsutoki Hatta, Hiroyuki Ishikawa, ...
    2014 Volume 124 Issue 2 Pages 230-243
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: January 31, 2014
    JOURNALS FREE ACCESS
    Transforming growth factor-β1 (TGF-β1) reportedly causes the differentiation of fibroblasts to myofibroblasts during wound healing. We investigated the mechanism underlying the activation of latent TGF-β1 released by keratinocytes in efforts to identify promising pharmacological approaches for the prevention of hypertrophic scar formation. A three-dimensional collagen gel matrix culture was prepared using rat keratinocytes and dermal fibroblasts. Stratified keratinocytes promoted the TGF receptor–dependent increase in α-smooth muscle actin (α-SMA) immunostaining and mRNA levels in fibroblasts. Latent TGF-β1 was found to be localized suprabasally and secreted. α-SMA expression was inhibited by an anti-αv-integrin antibody and a matrix metalloproteinase (MMP) inhibitor, GM6001. In a two-dimensional fibroblast culture, α-SMA expression depended on the production of endogenous TGF-β1 and required αv-integrin or MMP for the response to recombinant latent TGF-β1. In keratinocyte-conditioned medium, MMP-dependent latent TGF-β1 secretion was detected. Applying this medium to the fibroblast culture enhanced α-SMA production. This effect was decreased by GM6001, the anti-αv-integrin antibody, or the preabsorption of latent TGF-β1. These results indicate that keratinocytes secrete latent TGF-β1, which is liberated to fibroblasts over distance and is activated to produce α-SMA with the aid of a positive-feedback loop. MMP inhibition was effective for targeting both keratinocytes and fibroblasts in this model.
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  • Minoru Sakakiyama, Sanae Maeda, Kouichi Isami, Kayoko Asakura, Kanako ...
    2014 Volume 124 Issue 2 Pages 244-257
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: February 04, 2014
    JOURNALS FREE ACCESS
    The acute analgesic effect of tramadol has been extensively investigated; however, its long-term effect on neuropathic pain has not been well clarified. In this study, we examined the effects of repeated administration of tramadol on partial sciatic nerve ligation–induced neuropathic pain in rats. Each drug was administered once daily from 0 – 6 days (preventive effect) or 7 – 14 days (alleviative effect) after the surgery. Mechanical allodynia was evaluated just before (preventive or alleviative effect) and 1 h after (analgesic effect) drug administration. Like morphine, first administration of tramadol (20 mg/kg) showed an acute analgesic effect on the developed mechanical allodynia, which was diminished by naloxone. Like amitriptyline, repeated administration of tramadol showed preventive and alleviative effects on the mechanical allodynia that was diminished by yohimbine, but not naloxone. The alleviative effects of tramadol lasted even after drug cessation or in the presence of yohimbine. Repeated administration of tramadol increased the dopamine β-hydroxylase immunoreactivity in the spinal cord. Furthermore, tramadol inhibited the nerve ligation–induced activation of spinal astrocytes, which was reduced by yohimbine. These results suggest that tramadol has both μ-opioid receptor–mediated acute analgesic and α2-adrenoceptor–mediated preventive and alleviative effects on neuropathic pain, and the latter is due to α2-adrenoceptor–mediated inhibition of astrocytic activation.
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  • Yuta Aoki, Hirokazu Mizoguchi, Chizuko Watanabe, Kumiko Takeda, Tsukas ...
    2014 Volume 124 Issue 2 Pages 258-266
    Published: February 20, 2014
    Released: February 19, 2014
    JOURNALS FREE ACCESS
    The antinociceptive effect of morphine in the inflammatory pain state was described in the von Frey filament test using the complete Freund’s adjuvant (CFA)-induced mouse inflammatory pain model. After an i.pl. injection of CFA, mechanical allodynia was observed in the ipsilateral paw. The antinociceptive effect of morphine injected s.c. and i.t. against mechanical allodynia was reduced bilaterally at 1 day and 4 days after the CFA pretreatment. The expression level of mRNA for μ-opioid receptors at 1 day after the CFA pretreatment was reduced bilaterally in the lumbar spinal cord and dorsal root ganglion (DRG). In contrast, the protein level of μ-opioid receptors at 1 day after CFA pretreatment was decreased in the ipsilateral side in the DRG but not the lumbar spinal cord. Single or repeated i.t. pretreatment with the protein kinase Cα (PKCα) inhibitor Ro-32-0432 completely restored the reduced morphine antinociception in the contralateral paw but only partially restored it in the ipsilateral paw in the inflammatory pain state. In conclusion, reduced morphine antinociception against mechanical allodynia in the inflammatory pain state is mainly mediated via a decrease in μ-opioid receptors in the ipsilateral side and via the desensitization of μ-opioid receptors in the contralateral side by PKCα-induced phosphorylation.
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  • Natsumi Aoki, Hiroyuki Watanabe, Kazuya Okada, Kazuyuki Aoki, Takuma I ...
    2014 Volume 124 Issue 2 Pages 267-275
    Published: February 20, 2014
    Released: February 19, 2014
    [Advance publication] Released: February 04, 2014
    JOURNALS FREE ACCESS
    Several lines of evidence suggest that 5-HT receptors play a critical role in the expression of clock genes in the suprachiasmatic nucleus, the main circadian oscillator in hamsters. The contributions of 5-HT-receptor subtypes in the intestine, where they are expressed at high concentrations, are however not yet clarified. The 5-HT synthesis inhibitor, p-chlorophenylalanine, attenuated the daily rhythm of Per1 and Per2 gene expression in the intestine. Injection of 5-HT and agonists of the 5-HT3 and 5-HT4 receptors increased Per1/Per2 expression and decreased Bmal1 expression in a dose-dependent manner. Although treatment with antagonists of 5-HT3 and 5-HT4 alone did not affect clock gene expression, co-injection of these antagonists with 5-HT blocked the 5-HT-induced changes in clock gene expression. Increased tissue levels of 5-HT due to treatment with the antidepressants clomipramine and fluvoxamine did not affect clock gene expression. The present results suggest that the 5-HT system in the small intestine may play a critical role in regulating circadian rhythms through 5-HT3/5-HT4-receptor activation.
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  • Masahiro Kubo, Masaki Fukui, Yuma Ito, Tatsuya Kitao, Hiroaki Shirahas ...
    2014 Volume 124 Issue 2 Pages 276-285
    Published: February 20, 2014
    Released: February 19, 2014
    JOURNALS FREE ACCESS
    The pharmacological profile of (S)-7-(2-{2-[(E)-2-cyclopentylvinyl]-5-methyloxazol-4-yl}-ethoxy)-2-[(2E,4E)-hexadienoyl]-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (KY-201), a peroxisome proliferator-activated receptor (PPAR) γ agonist, was compared with that of rosiglitazone in ovariectomized rats. The serum triglyceride and non-esterified fatty acid reducing effects of KY-201 at 3 and 10 mg/kg per day for 6 weeks were similar to those of rosiglitazone despite its weaker PPARγ agonistic activity. KY-201 had no effects on body weight gain, blood volume, or heart and adipose weights, while rosiglitazone at 10 mg/kg per day increased them. KY-201 had few effects on bone mineral density (BMD) or fat in marrow (FM), whereas rosiglitazone strongly decreased BMD and increased FM. The PPARγ agonistic activity of KY-201 was weaker than that of rosiglitazone in ST-2 cells, and KY-201 reduced osteoblast differentiation and increased adipocyte differentiation less potently than rosiglitazone in rat bone marrow-derived mesenchymal stem cells. KY-201, but not rosiglitazone inhibited protein tyrosine phosphatase 1B (PTP1B) and increased phosphorylation of the insulin receptor in HepG2 cells. These results suggest that the hypolipidemic effects of KY-201 are similar to those of rosiglitazone, but with less adverse effects, due to the combination of PPARγ partial activation and PTP1B inhibition. KY-201 would be useful for treatments of diabetic patients at high risk of osteoporosis, cardiovascular disease, and/or obesity.
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