Honokiol : A Noncompetitive Tyrosinase Inhibitor from Magnoliae Cortex

Yu-Hua Tian,Tai-hyun Kang,Hyun-Chul Kim,Youn-Chul Kim 한국생약학회 2005 Natural Product Sciences Vol.11 No.2

Effect of the neolignans, honokiol (1) and magnolol (2), isolated from Magnoliae Cortex onmushroom tyrosinase activity was investigated in vitro using L-tyrosine as a substrate. Honokiol (1) inhibited2) did notshow tyrosinase inhibitory effect. Honokiol exhibited tyrosinase inhibitory effect with IC50 value of 67.9M, andproved to act as a non-competitive inhibitor by the analysis of Lineweaver-Burk plot.

7-Nitroindazole, nitric oxide synthase inhibitor, attenuates physical dependence on butorphanol in rat

Tian, Yu-Hua,Lee, Kwang-Wook,You, In-Jee,Lee, Seok-Yong,Jang, Choon-Gon Wiley Subscription Services, Inc., A Wiley Company 2008 Synapse Vol.62 No.8

<P>Butorphanol is a synthetic opioid agonist/antagonist analgesic agent that mainly exerts its effects through κ-opioid receptors. It has been demonstrated that κ-opioid receptors preferentially mediate the development of physical dependence upon butorphanol and the associated withdrawal syndrome. However, it is not fully understood whether or not nNOS-containing neurons in the various brain regions play an important role in butorphanol withdrawal. Therefore, this study was conducted to determine whether the selective nNOS inhibitor, 7-NI, modifies the development of butorphanol withdrawal and changes of nNOS expressions in different brain regions in physically butorphanol-dependent rats. The first part of the study focused on withdrawal behaviors in male Sprague-Dawley rats. Physical dependence was induced by a 72-h i.c.v. infusion with butorphanol (26 nmol/μl/h) and withdrawal was subsequently precipitated by i.c.v. challenge with naloxone (48 nmol/5 μl/rat) 2 h after termination of the butorphanol infusion. The butorphanol/7-NI coadministration group showed a significant decrease in several signs of withdrawal such as teeth chattering, as compared with the butorphanol-treated group. In the second part of the study, immunohistochemical analysis was performed to determine the expression of nNOS in the various brain regions. In the butorphanol/7-NI coadministration group, the number of cells labeled for nNOS was significantly lower in the various brain regions (including the caudate putamen, nucleus accumbens, and hippocampus) than in the butorphanol group. Therefore, 7-NI decreased in butorphanol-induced physical dependence and nNOS expression. Taken together, these findings suggest that the nNOS system is involved in the development of butorphanol-induced physical dependence, and 7-NI has potential clinical application as a candidate for the treatment of opioid withdrawal syndrome. Synapse 62:582–589, 2008. © 2008 Wiley-Liss, Inc.</P>

Prenatal and postnatal exposure to bisphenol a induces anxiolytic behaviors and cognitive deficits in mice

Tian, Yu-Hua,Baek, Joung-Hee,Lee, Seok-Yong,Jang, Choon-Gon Wiley Subscription Services, Inc., A Wiley Company 2010 Synapse Vol.64 No.6

<P>Bisphenol A (BPA), an environmental endocrine-disrupting chemical, has been extensively evaluated for reproductive toxicity and carcinogenicity. However, little is known about the behavioral and neurochemical effects of BPA exposure. This study examined whether chronic daily exposure to an environmental endocrine-disrupting chemical, bisphenol A [(BPA); 100 μg/kg/day or 500 μg/kg/day, p.o.], from prenatal Day 7 to postnatal Day 36 would lead to changes in anxiety and memory in mice. First, we observed the behavioral alterations of BPA-treated mice using two anxiety-related models, the open field test and elevated plus maze (EPM) test. In the open field test, BPA treatment (100 μg/kg/day) increased movement in the central zone. BPA treatment (500 μg/kg/day) also increased the time spent in the open arms in the EPM test. Second, we measured cognitive ability in the Y-maze test and novel object test. BPA-treated mice showed decreased alternation behavior in the Y-maze at both of doses, indicating working memory impairment. BPA-treated mice (100 μg/kg/day) also showed decreased novel object recognition as expressed by central locomotion and frequency in the central zone, showing recognition memory impairment. Finally, to measure changes in the dopaminergic and NMDAergic systems in the brain, we performed autoradiographic receptor binding assays for dopamine D<SUB>1</SUB> and D<SUB>2</SUB> receptors, the NMDA receptor, and the dopamine transporter. BPA treatment increased D<SUB>2</SUB> receptor binding in the caudate putamen (CPu) but decreased DAT binding. BPA treatment also decreased NMDA receptor binding in the frontal cortex and CA1, CA3, and DG of the hippocampus. Taken together, our results suggest that long-term BPA exposure in mice can induce anxiolytic behaviors, cognitive deficits and changes in the dopaminergic and NMDAergic systems. Synapse 64:432–439, 2010. © 2010 Wiley-Liss, Inc.</P>

Hepatoprotective Constituents of Cudrania tricuspidata

Tian Yu-Hua,Kim Hyun-Chul,Cui Jiong-Mo,Kim Youn-Chul The Pharmaceutical Society of Korea 2005 Archives of Pharmacal Research Vol.28 No.1

Phytochemical investigation of the MeOH extract of the root barks of Cudrania tricuspidata Bureau (Moraceae), as guided by hepatoprotective activity in vitro, furnished four isoprenylated xanthones, cudratricusxanthone A (1), cudraxanthone L (2), cudratricusxanthone E (3), and macluraxanthone B (4). All of these compounds showed the significant hepatoprotective effect on tacrine-induced cytotoxicity in human liver-derived Hep G2 cells. Compounds 1, 2, and 4 also exhibited the significant hepatoprotective effect on nitrofurantoin-induced cytotoxicity in human liver-derived Hep G2 cells.

Hepatoprotective Constituents of Cudrania tricuspidata

Yu-Hua Tian,Hyun-Chul Kim,Jiong-Mo Cui,Youn-Chul Kim 대한약학회 2005 Archives of Pharmacal Research Vol.28 No.1

Phytochemical investigation of the MeOH extract of the root barks of Cudrania tricuspidata Bureau (Moraceae), as guided by hepatoprotective activity in vitro, furnished four isoprenylated xanthones, cudratricusxanthone A (1), cudraxanthone L (2), cudratricusxanthone E (3), and macluraxanthone B (4). All of these compounds showed the significant hepatoprotective effect on tacrine-induced cytotoxicity in human liver-derived Hep G2 cells. Compounds 1, 2, and 4 also exhibited the significant hepatoprotective effect on nitrofurantoin-induced cytotoxicity in human liver-derived Hep G2 cells.

Lactational and postnatal exposure to polychlorinated biphenyls induces sex‐specific anxiolytic behavior and cognitive deficit in mice offspring

Tian, Yu‐,Hua,Hwan Kim, Seung,Lee, Seok‐,Yong,Jang, Choon‐,Gon Wiley Subscription Services, Inc., A Wiley Company 2011 Synapse Vol.65 No.10

<P><B>Abstract</B></P><P>The central nervous system is affected by polychlorinated biphenyls (PCBs). Previous studies have indicated that developmental exposure to PCBs impairs behavioral performance and alters cognitive abilities. This study assessed the effects of lactational and postnatal exposure to a commercial PCBs mixture, Aroclor 1254 (A1254), on mice performing several neurobehavioral tasks including the open field test, novel object test, elevated plus maze test, Y‐maze test, and tail suspension test. In the open field test, PCBs treatment (6 and 18 mg/kg/day) was associated with increased movement, time duration, and frequency in the central zone in female but not male mice. PCBs‐treated female mice (6 and 18 mg/kg/day) also showed decreased novel object recognition, indicating impairment in recognition memory. Finally, we performed autoradiographic receptor binding assays for dopamine (DA) D<SUB>1</SUB> and D<SUB>2</SUB> receptors, dopamine transporter (DAT), and the N‐methyl‐<SMALL>D</SMALL>‐aspartic acid (NMDA) receptor after behavioral tests to examine whether alterations occurred in the dopaminergic and NMDAergic systems of the brain. Our results showed that PCBs treatment did not change D<SUB>1</SUB> and D<SUB>2</SUB> receptors or DAT binding in the dorsal striatum of female mice. However, PCBs treatment significantly decreased NMDA receptor binding in the dorsal striatum, frontal cortex, cingulate cortex, and motor cortex, and CA3 and dentate gyrus (DG) of the hippocampus in female mice. Collectively, our results suggest that long‐term PCBs exposure can induce anxiolytic behavior, cognitive deficits, and changes of NMDA receptors. Synapse, 2011. © 2011 Wiley©Liss, Inc.</P>

Protective Effect of Ultra Low Molecular Weight Heparin on Glutamate-Induced Apoptosis in Cortical Cells

Tian-Gui Yu,Qing-Zhu Zhang,Zhi-Guo Zhang,Wei-Wei Wang,Sheng-Li Ji,Guan-Hua Du 연세대학교의과대학 2008 Yonsei medical journal Vol.49 No.3

Purpose: To investigate the effect of ultra low molecular weight heparin (ULMWH) on glutamate induced apoptosis in rat cortical cells and to explore the possible mechanisms. Materials and Methods: Cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Apoptosis was first analyzed with Hoechst 33258 and then confirmed by DNA fragmentation. The concentration of free intracellular calcium ([Ca²+]i) was determined with fura-2/AM fluorometry. The expression of Bcl-2 family protein and caspase-3 were evaluated with Western blot. Results: Typical apoptotic morphological change in rat cortical cells treated with 100μmol/L glutamate for 24h was detected by Hoechst 33258 staining, which was then confirmed by the DNA ladder of agarose gel electrophoresis. The apoptotic rate of the glutamate treated cells was up to 33.21%, and 24 h of treatment with glutamate increased [Ca²+]i, down-regulated Bcl-2 expression, up-regulated Bax expression, and increased caspase-3 activation in rat cortical cells. Our research demonstrated that ULMWH pretreatment can prevent the glutamate- induced apoptosis, attenuate the increase of [Ca²+]i not only in medium containing Ca²+ but also in Ca²+-free medium, up-regulate the expression of Bcl-2, down-regulate the expression of Bax, and decrease caspase-3 activation. Conclusion: ULMWH has neuroprotective capacity to antagonize glutamate-induced apoptosis in cortical cells, through decrease of Ca²+ release and modulation of apoptotic processes.

Factors that Influence the Presciption of Antipsychotics for Patients with Schizophrenia in China

Tian-Mei Si,Liang Shu,Ke-Qing Li,Xie-He Liu,Qi-Yi Mei,Gao-Hua Wang,Pei-Shen Bai,Li-Ping Ji,Xian-Sheng Chen,Cui Ma,Jian-Guo Shi,Hong-Yan Zhang,Hong Ma,Xin Yu 대한정신약물학회 2011 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.9 No.3

Objective: To investigate the patterns of antipsychotic use in China and to analyze the factors that influence antipsychotic prescriptions. Methods: A standardized survey was conducted from May 20 to 24 2002 in five different regions of China with varying economic levels. The patterns of antipsychotic medication use were analyzed in a sample of 4,779 patients with schizophrenia. The survey gathered information on demographic characteristics, clinical profiles, and antipsychotic medications prescribed. Multiple logistic regression was used to analyze factors related to patterns of antipsychotic medication use. Results: A plurality of patients with schizophrenia was treated with clozapine (39%); this was followed by risperidone, sulpride,chlorpromazine, perphenazine, and haloperidol. More than 56.3% of patients were treated with only one atypical antipsychotic. The mean daily dose of chlorpromazine was 365±253 mg (mean±standard deviation), and 6.5% of patients were treated with depot injections of typical antipsychotic medications. A total of 73.7% (n=3,523) of patients with schizophrenia received monotherapy,24.8% (n=1,183) received two antipsychotics, 1.1% (n=52) received three antipsychotics, and one received four different antipsychotics. Patients often simultaneously received other classes of medications including anticholinergic agents, benzodiazepines,β-blockers, antidepressants, and mood stabilizers. Economic status and clinical symptoms were the main factors that contributed to the patterns of antipsychotic prescription. Conclusion: The present study suggests that atypical antipsychotic medications, especially clozapine, are the primary psychiatric treatments of choice in the management of schizophrenia in China. Moreover, the economic status and clinical profile of the patient are the major factors affecting the prescription of antipsychotic medication.

Use of Clozapine for the Treatment of Schizophrenia: Findings of the 2006 Research on the China Psychotropic Prescription Studies

Tian-Mei Si,Yun-shu Zhang,Liang Shu,Ke-Qing Li,Xie-He Liu,Qi-Yi Mei,Gao-Hua Wang,Pei-Shen Bai,Li-Ping Ji,Xian-Sheng Cheng,Cui Ma,Jian-Guo Shi,Hong-Yan Zhang,Hong Ma,Xin Yu 대한정신약물학회 2012 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.10 No.2

Objective: Clozapine is one of the most commonly used antipsychotic drugs in China. To date, few studies have investigated the patterns the prescription of clozapine nationwide. The present study examined these patterns in China in 2006 and identified the demographic and clinical characteristics associated with the use of clozapine. Methods: Using a standardized protocol and data collection procedure, we surveyed 5,898 patients with schizophrenia in 10provinces with differing levels of economic development. Results: Overall, clozapine had been prescribed for 31.9% (n=1,883) of the patients; however we found considerable variation among the 10 provinces. The frequency of clozapine use was highest in Sichuan (39.3%) and lowest in Beijing (17.3%). The mean daily dose of clozapine was 210.36±128.72 mg/day, and 25.1% of the patients were treated with clozapine in combination with other antipsychotics. Compared with the group not receiving clozapine, clozapine-user had been treated for longer durations and had experienced a greater number of relapses and hospitalizations. Furthermore, those in the clozapine-user had lower family incomes, were less able to seek psychiatric services, and more likely to be male and have a positive family history of schizophrenia. A multiple logistic regression analysis revealed that age, sex, professional help-seeking behaviors, duration of illness, economic status, educational level, and clinical manifestations were associated with the use of clozapine. Conclusion: Clozapine use is common in China. However, use of the antipsychotic varies among provinces, and demographic and clinical factors play important roles in the prescription of clozapine.

A New Quorum-Sensing Inhibitor Attenuates Virulence and Decreases Antibiotic Resistance in Pseudomonas aeruginosa

Yu-Xiang Yang,Zhen-Hua Xu,Yu-Qian Zhang,Jing Tian,Li-Xing Weng,Lian-Hui Wang 한국미생물학회 2012 The journal of microbiology Vol.50 No.6

Quorum sensing (QS) has been a novel target for the treatment of infectious diseases. Here structural analogs of Pseudomonas aeruginosa autoinducer N-acyl homoserine lactone (AHL) were investigated for QS inhibitor (QSI) activity and a novel QSI was discovered, N-decanoyl-L-homoserine benzyl ester (C2). Virulence assays showed that C2 downregulated total protease and elastase activities, as well as the production of rhamnolipid, that are controlled by QS in P.aeruginosa wild-type strain PAO1 without affecting growth. C2 was also shown to inhibit swarming motility of PAO1. Using a microdilution checkerboard method, we identified synergistic interactions between C2 and several antibiotics, tobramycin, gentamycin, cefepime, and meropenem. Data from real-time RT-PCR suggested that C2 inhibited the expression of lasR (29.67%), lasI (21.57%), rhlR (28.20%), and rhlI (29.03%).