Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist inhibits apoptosis of retinal ganglion cells in a rabbit model of optic nerve injury

A rabbit model of traumatic optic nerve injury, established by occlusion of the optic nerve using a vascular clamp, was used to investigate the effects of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist GYKI 52466 on apoptosis of retinal ganglion cells following nerve injury. Hematoxylin-eosin staining and a terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that retinal ganglion cells gradually decreased with increasing time of optic nerve injury, while GYKI 52466 could inhibit this process. The results demonstrate that following acute optic nerve injury, apoptosis of retinal ganglion cells is a programmed process, which can be inhibited by the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist.

Optical 2-benzyl-5-hydroxy-4-oxopentanoic acids against carboxypeptidase A:Synthesis,kinetic evaluation and X-ray crystallographic study

2-Benzyl-5-hydroxy-4-oxopentanoic acid 1 and its enantiomers were designed,synthesized and assayed for inhibitory activity against carboxypeptidase A(CPA,EC 3.4.17.1).To verify the role of the terminal hydroxyl group in 1 binding to CPA,2-benzyl-5- benzyloxy-4-oxopentanoic acid 2 was also synthesized and evaluated.The inhibition constants show that both L-1 and D-1 were shown to have strong binding affinity with L-1 being more potent than its enantiomer by 165-fold.On the other hand,the inhibition constant ...

A convenient synthesis of methyl 2-hydroxy-4-oxo-4-(substituted phenyl) butanoates from malic acid

A synthesis of methyl 2-hydroxy-4-oxo-4-（substituted phenyl）butanoates has been accomplished using Friedel-Crafts acylation of substituted benzenes with 2-acetoxybutanoyl chloride. The key feature of this strategy is that various 4-arylbutanoates can be obtained conveniently, which are important intermediates for the synthesis of biologically active compounds including ACE inhibitors.？2009 Yong Sup Lee. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Role of α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor regulation in stress-induced pain chronification

Persistent postsurgical pain is a serious issue in public health, which has received increased interest in recent years. Previous studies have reported that psychological factors promote the development of chronic postsurgical pain. However, it is unclear how chronification of postsurgical pain occurs. The α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor(AMPA) phosphorylation in the central nervous system plays a critical role in synaptic plasticity and contributes to central sensitization and chronic pain development. Here, we discuss the role of AMPA receptor regulation in stress-induced pain chronification after surgery.

A New Chiral Synthesis of Naturally Occurring (-)-(S)-4-Hydroxy-2-pyrrolidinone

A new and convenient chiral synthesis of naturally occurring (-)-(S)-4-hydroxy-2-pyrrolidinone from (S)-malic acid was reported.

Dietary supplementation with 2-hydroxy-4-methyl(thio)butanoic acid and DL-methionine improves productive performance,egg quality and redox status of commercial laying ducks

This experiment aimed to study the effects of supplemental methionine sources,2-hydroxy-4 methyl(thio)butanoic acid(HMTBa)and DL-Methionine(DL-Met),on productive performance,egg quality,and redox status of laying ducks.A total of 792 healthy 25-wk-old Longyan laying ducks with similar body weights were randomly allotted to 11 treatment groups.Each treatment group had 6 replicates of 12 ducks.The trial lasted for 16 wk.Ducks were fed a basal deficient diet(Met:0.24%;Met+Cys:0.51%)or supplemented with DL-Met or HMTBa at 0.05%,0.12%,0.19%,0.26%,and 0.33%of diet,respectively.Compared with the basal diet,supplementation with either DL-Met or HMTBa increased the average egg weight,egg mass,and decreased feed to egg ratio during the whole trial period(P<0.05).Albumen weight and its ratio to total egg weight were increased,but yolk and shell ratio,albumen height,Haugh unit and shell breaking strength were decreased(P<0.05).Dietary DL-Met or HMTBa supplementation increased taurine,methionine,leucine,tryptophan and arginine content,and decreased serine and lysine content in plasma(P<0.05).The redox status of laying ducks was improved by enhancing the glutathione peroxidase and catalase activities,glutathione content and its ratio relative to glutathione(oxidized)content and decreasing malondialdehyde content and increasing mRNA expression of superoxide dismutase-1,glutathione peroxidase-1,hemeoxygenase-1 and nuclear factor-like 2 in liver and ileum with the supplementation of DL-Met or HMTBa(P<0.05).Liver health status measured by average area proportion lipid droplet was improved with supplementation of DL-Met or HMTBa(P<0.05).Villus height and villus height to crypt depth ratio in the ileum and the ileal gene expression of tight junction protein and occludin were increased with DL-Met or HMTBa supplementation(P<0.05).Taken together,these results suggested that the efficacy of dietary supplementation of HMTBa was similar to DL-Met,and it ranged from 98%to 100%for productive performance and egg albumen ratio in laying ducks(25 to 41 wk).

Synthesis, Structure and Properties of Two New Coordination Polymers Based on 4-[（8-Hydroxy-5-quinolinyl）azo]-benzenesulfonic Acid

Two new coordination polymers based on 4-[（8-hydroxy-5-quinolinyl）azo]-benzenesulfonic acid（H2L）,{[CdL（H2O）2]·H2O}n（1） and {[CdL（en）]·EtOH}n（2）（en=ethylenediamine）,were solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction.Compounds 1 and 2 exhibit infinite 1D ladder-shaped chain structures,which are isostructural except that the two coordinating water molecules in compound 1 were replaced by one en molecule in compound 2 due to the use of different organic base.Compounds 1 and 2 were constructed into different supramolecular frameworks by hydrogen bonding and π…π stacking interactions.In addition,the fluorescent properties of compounds 1 and 2 were investigated.Furthermore,they were also investigated via IR spectral analysis,elemental analysis,powder X-ray diffraction（PXRD） and thermogravimetric analysis（TGA）.

A New Sesquiterpene-substituted Benzoic Acid from the Brown Alga Dictyopteris divaricata

A new sesquiterpene-substituted benzoic acid has been isolated from the brown Alga Dictyopteris divaricata Okam.. Its structure was elucidated as 3-[(2-hydroxy-2,5,5,8a-tetra- methyldecahydro-1-naphthalenyl)methyl]-4-hydroxybenzoic acid, named dictyvaric acid on the basis of spectroscopic methods including IR, HRFABMS, 1D and 2D NMR techniques.

Synthesis, Structure and Fluorescent Property of Coordination Polymer from 4-[（8-Hydroxy-5-quinolinyl）azo]-benzoic Acid

One new coordination polymer based on 4-[（8-hydroxy-5-quinolinyl）azo]-benzoic acid（H2L）, { [CdL（H20）]·H2O}n（1） was solvothermally synthesized and structurally characterized by single-crystal X-ray diffrac- tion, infrared spectrometry, elemental analysis, powder X-ray diffraction（PXRD） and thermogravimetric analysis （TGA）. In compound 1, L2- ligands link Cd（II） to form a sinusoidal ruffling layer, in which the carboxylic groups connect Cd（II） into an infinite Cd--O chain. And the layers are further stabilized by hydrogen bonding and π-π in- teractions, forming a three-dimensional（3D） supramolecular network. In addition, the fluorescent property of compound 1 was also investigated.

Clinical features of AMPAR2 antibody-positive autoimmune encephalitis with gastrointestinal hemorrhage: a case report

Objective:To describe the clinical features of autoimmune encephalitis complicated with gastrointestinal hemorrhage.Methods:The clinical data of one patient whose initial symptom was mental abnormality were collected and the related examinations,such as cerebrospinal fluid and magnetic resonance imaging (MRI),were improved.Results: Cerebrospinal fluid examination found that anti-α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor(AMPAR)2 antibody was strongly positive,although the patient had repeated gastrointestinal hemorrhage but,after hormone combined with immunoglobulin treatment,the symptoms gradual-ly improved.Conclusion:Mental disorders are not all psychosis,and autoimmune encephalitis should not be ignored.It is very important to perform anti-AMPAR encephalitis antibody test;accurate diagnosis and timely treatment can improve the prognosis.

4-(Succinimido)-1-butane sulfonic acid as a Bronsted acid catalyst for synthesis of pyrano[4,3-b]pyran derivatives under solvent-free conditions

4-（Succinimido）-1-butane sulfonic acid as an efficient and reusable Bronsted acid catalyzed the synthesis of pyrano[4,3-b]pyran derivatives under solvent-free conditions.The catalyst can be prepared by mixing succinimide and 1,4-butanesultone that is more simple and safer than the preparation of succinimide sulfonic acid.This method has the advantages of high yield,clean reaction,simple methodology and short reaction time.The catalyst could be recycled without significant loss of activity.

Chemical Constituents from Piper wallichii

Aim To investigate the chemical constituents of Piper wallichii. Methods Five compounds were isolated by silica gel column chromatography and Sephadex LH-20 gel column chromatography, and the structures of compounds were identified by spectral analysis. Result Five compounds were identified as piperlonguminine （trans, trans） （1）, 4-hydroxy-3,5-dimethoxy-benzoic acid （2）, galgravin （3）, β-sitosterol （4）, and daucosterol （5）. Conclusion Five compounds were isolated from Piper wallichii for the first time, and compounds 1 -3 were isolated from this genus far the first time.

野鸦椿的植物化学成分研究

从野鸦椿 (EuscaphisjaponecaKantiz)枝叶的甲醇提取物分离得到 6个化合物 ,通过波谱分析鉴定为 5 ,7 dihydroxy 2 methyl benzopyran 4 one(Ⅰ ) ,3,4 ,5 trihydroxy benzoicacidmethylester(Ⅱ ) ,3,7 dihydroxy 5 octanolide(Ⅲ ) ,methyl 5 ,7 dihydroxy 2 (Z) octenoate(Ⅳ ) ,7 hydroxy 2 octen 5 olide(Ⅴ )和vomifoliol(Ⅵ )。

Modified constraint-induced movement therapy alters synaptic plasticity of rat contralateral hippocampus following middle cerebral artery occlusion

Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.However,the molecular mechanism underlying its efficacy remains unclear.In this study,a middle cerebral artery occlusion(MCAO)rat model was produced by the suture method.Rats received modified constraint-induced movement therapy 1 hour a day for 14 consecutive days,starting from the 7^th day after middle cerebral artery occlusion.Day 1 of treatment lasted for 10 minutes at 2r/min,day 2 for 20 minutes at 2 r/min,and from day 3 onward for 20 minutes at 4 r/min.CatWalk gait analysis,adhesive removal test,and Y-maze test were used to investigate motor function,sensory function as well as cognitive function in rodent animals from the 1st day before MCAO to the 21^st day after MCAO.On the 21^st day after MCAO,the neurotransmitter receptor-related genes from both contralateral and ipsilateral hippocampi were tested by micro-array and then verified by western blot assay.The glutamate related receptor was shown by transmission electron microscopy and the glutamate content was determined by high-performance liquid chromatography.The results of behavior tests showed that modified constraint-induced movement therapy promoted motor and sensory functional recovery in the middle cerebral artery-occluded rats,but had no effect on cognitive function.The modified constraint-induced movement therapy upregulated the expression of glutamate ionotropic receptor AMPA type subunit 3(Gria3)in the hippocampus and downregulated the expression of the beta3-adrenergic receptor gene Adrb3 and arginine vasopressin receptor 1 A,Avprla in the middle cerebral artery-occluded rats.In the ipsilateral hippocampus,only Adra2 a was downregulated,and there was no significant change in Gria3.Transmission electron microscopy revealed a denser distribution the more distribution of postsynaptic glutamate receptor 2/3,which is an a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor,within 240 nm of the postsynaptic density in the contralateral cornu ammonis 3 region.The size and distribution of the synaptic vesicles within 100 nm of the presynaptic active zone were unchanged.Western blot analysis showed that modified constraint-induced movement therapy also increased the expression of glutamate receptor 2/3 and brain-derived neurotrophic factor in the hippocampus of rats with middle cerebral artery occlusion,but had no effect on Synapsin I levels.Besides,we also found modified constraint-induced movement therapy effectively reduced glutamate content in the contralateral hippocampus.This study demonstrated that modified constraint-induced movement therapy is an effective rehabilitation therapy in middle cerebral artery-occluded rats,and suggests that these positive effects occur via the upregulation of the postsynaptic membrane a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor expression.This study was approved by the Institutional Animal Care and Use Committee of Fudan University,China(approval No.201802173 S)on March 3,2018.

A new pyrrolidone derivative from Pistacia chinensis

A new N-phenyl-pyrrolidone derivative had been isolated from Pistacia chinesis Bunge. Its structure was elucidated as 4-hydroxy-5-（2-oxo-1-pyrrolidinyl）-benzoic acid, named pistaciamide on the basis of the 1D-NMR, DEPT, HMQC and HMBC spectroscopic techniques. 2007 Xi Kui Liu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Indole Alkaloids from the Roots of Ervatamia hainanensis

Two new indole alkaloids, named ibogamine-18-carboxylic acid, 3, 4-didehydro-7, 8-dioxo-methyl ester 1, ibogamine-18-carboxylic acid, 16, 17-didehydro-9, 17-dihydro-9-hydroxy （2-oxopropyl）-methyl ester 2, were isolated from Ervatamia hainanensis. Their structures were elucidated on the basis of spectroscopic methods.

Pharmacokinetics of oxiracetam and its degraded substance (HOPAA) after oral and intravenous administration in rats

The pharmacokinetics of oxiracetam and its degraded substance(4-hydroxy-2-oxo-1-pyrrolidine acetic acid,HOPAA)after oral and intravenous administration in rats were studied using an established UPLC-MS/MS method.Three groups of rats after an overnight fasted received 10 g/kg(n=6)oxiracetam suspensions orally,and 2 g/kg(n=6)normal or degraded oxiracetam injections intravenously via a caudal tail vein,respectively.Before the pharmacokinetic experiment,a simple safety evaluation testwas conducted on the degraded oxiracetam injections containing 16.16% HOPAA in mice.There was no mortality by a single intravenous dose of 2 g/kg of degraded oxiracetam injections within twoweeks,demonstrating that HOPAA was non-toxic in mice.Following intravenous administration of the normal injections,the plasma concentration-time curves of oxiracetam and HOPAA both showed a rapid elimination phase.The values of t_(1/2)were 3.1±1.5 h for oxiracetamand 0.8±0.2 h for HOPAA,andthemean residencetimes(MRT)were 1.2±0.1h and 0.8±0.1h,respectively.Oxiracetam and HOPAA after intravenous administration of the degraded oxiracetam injections presented elimination patterns similar to those observed in the normal injections.Oral pharmacokinetic results showed that the Tmax was less than 1.5 h for the two analytes,and both had a longer t_(1/2) and MRT than those of intravenous administration.Contents of HOPAA in three groupswere calculated based on AUC_(0-t) values of the two analytes.The quantitative change of HOPAA in vivo was also evaluated by comparing the plasma concentrations of HOPAA and oxiracetamat the same time for every group.Additionally,the values of absolute bioavailability of oxiracetam were about 8.0%and 7.4%calculated by the normal or degraded oxiracetam injections,whichwere far less than the value of 75%reported in literature,indicating the necessity of further study.

Binocular form deprivation influences the visual cortex

a-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors are considered to play a crucial role in synaptic plasticity in the developing visual cortex. In this study, we established a rat model of binocular form deprivation by suturing the rat binocular eyelids before eye-opening at postnatal day 14. During development, the decay time of excitatory postsynaptic currents mediated by a-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid receptors of normal rats became longer after eye- opening; however, the decay time did not change significantly in binocular form deprivation rats. The peak value in the normal group became gradually larger with age, but there was no significant change in the binocular form deprivation group. These findings indicate that binocular form deprivation influences the properties of excitatory postsynaptic currents mediated by a-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid receptors in the rat visual cortex around the end of the critical period, indicating that form stimulation is associated with the experience-dependent modification of neuronal synapses in the visual cortex.

Genetic variables of the glutamatergic system associated with treatment-resistant depression:A review of the literature

Depression is a common,recurrent mental disorder and one of the leading causes of disability and global burden of disease worldwide.Up to 15%-40%of cases do not respond to diverse pharmacological treatments and,thus,can be defined as treatment-resistant depression(TRD).The development of biomarkers predictive of drug response could guide us towards personalized and earlier treatment.Growing evidence points to the involvement of the glutamatergic system in the pathogenesis of TRD.Specifically,the N-methyl-D-aspartic acid receptor(NMDAR)andα-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor(AMPAR),which are targeted by ketamine and esketamine,are proposed as promising pathways.A literature search was performed to identify studies on the genetics of the glutamatergic system in depression,focused on variables related to NMDARs and AMPARs.Our review highlights GRIN2B,which encodes the NR2B subunit of NMDAR,as a candidate gene in the pathogenesis of TRD.In addition,several studies have associated genes encoding AMPAR subunits with symptomatic severity and suicidal ideation.These genes encoding glutamatergic receptors could,therefore,be candidate genes for understanding the etiopathogenesis of TRD,as well as for understanding the pharmacodynamic mechanisms and response to ketamine and esketamine treatment.