Inhibition of ornithine-decarboxylase produced by S(+) and R(-) ibuprofen in rats

The differences between the S(+) and R(-) ibuprofen enantiomers in anti-inflammatory activity were assayed by measuring the release of 14CO2 in rats treated with labelled 14COOH-ornithine. Furthermore we investigated in vitro the inhibitory activity on ornithine-decarboxylase and the anti-inflammatory activity of R(-) and S(+) ibuprofen by using the carrageenin-induced paw oedema test in the rat.     

Desipramine attenuates working memory impairments induced by partial loss of catecholamines in the rat medial prefrontal cortex

Rationale The density of tyrosine hydroxylase-immunoreactive (TH-IR) axons in the prefrontal cortex of schizophrenic subjects may be reduced by as much as 50% in the deep cortical layers (Am J Psychiatry 156:1580–1589, 1999). Previously, we demonstrated that ~60% loss of TH-IR axons in the rat medial prefrontal cortex (mPFC) decreases local basal and stress-evoked extracellular dopamine (DA) concentrations, suggesting that moderate loss of DA axons in the mPFC is sufficient to alter the neurochemical activity of the remaining DA neurons (Neuroscience 93:497–505, 1999). Objectives To further assess the functional consequences of partial mPFC DA depletion, we examined the effects of 6-hydroxydopamine lesions of the rat mPFC on behavior in a T-maze delayed-response task. We also assessed whether chronic administration of the norepinephrine (NE) uptake inhibitor, desipramine (DMI), attenuates lesion-induced deficits in T-maze performance. Previous research indicates that inhibition of NE transport in the mPFC results in a concomitant increase in extracellular DA and NE. Results Moderate loss of mPFC DA and NE (~50 and 10% loss, respectively) was sufficient to impair delayed-response behavior, in part due to an increase in perseverative responding. Chronic DMI treatment (3 mg/kg delivered via osmotic pumps) impaired performance of control rats but attenuated the deficits in delayed-response behavior in rats previously sustaining loss of mPFC DA and NE (~75 and 35% loss, respectively). Conclusion These data suggest that moderate loss of DA and NE in the prefrontal cortex is sufficient to impair cognitive function, and these behavioral effects are attenuated by inhibition of the NE transporter.     

Optical isomerization of R(−)-clidanac to the biologically active S(+)-isomer in guinea-pigs

Optical isomerization of clidanac (RS-6-chloro-5-cyclohexyl-1-indancarboxylic acid, I), an anti-inflammatory drug having a chiral centre in its molecule, was evaluated in guinea-pigs. After oral administration of R(?)-I, the biologically active S(+)-isomer was detectable in the plasma, in the early stages. At 3 h after dosing R(?)-I, the plasma contained above 90% of the S(+)-isomer. Little conversion of S(+)-I to R(?)-I was observed. This may account for the equivalent in vivo activities of R(?)- and S(+)-I in this species. Determination of the enantiomeric composition required derivatization of the enantiomers to their diastereomeric amides after which thin layer chromatography (t.l.c.) was used for the separation. The quantitative determination of the compounds so-separated was accomplished by in situ measurements of the u.v.-reflectance. The t.l.c.-u.v.-densitometric procedure was also used to determine the plasma concentration of I.     

白藜芦醇减轻慢性神经炎症所致的大鼠空间学习记忆减退

目的:考察白藜芦醇对慢性炎症所致大鼠空间学习记忆减退的保护作用,探讨其作用机制。方法:雄性SD大鼠ip给予脂多糖20 mg·kg-1,每周1次,连续4周制备大鼠慢性神经炎症模型,同时ig给予白藜芦醇10,20,40 mg·kg-1·d-1,阳性组ig给予布洛芬40 mg·kg-1,连续26 d。给药d22行Morris水迷宫测定大鼠的空间学习记忆能力,连续5 d。实时定量PCR法测定大鼠海马组织肿瘤坏死因子α(TNF-α)、白细胞介素-1β(IL-1β)、诱导型一氧化氮合酶(iNOS)及环氧合酶-2(COX-2)mRNA的表达。结果:连续4周注射脂多糖(LPS)后,大鼠在定向航行实验中的逃避潜伏期明显增加,空间探索实验中的校正逃避潜伏期明显缩短,且海马组织中TNF-α,IL-1β,NOS2及COX-2基因的mRNA表达水平增加;白藜芦醇和布洛芬组大鼠定向航行实验中的逃避潜伏期明显缩短,空间探索实验中的校正逃避潜伏期延长,海马组织中TNF-α,IL-1β,NOS2及COX-2基因的mRNA表达水平降低。结论:白藜芦醇可减轻慢性神经炎症诱导的大鼠记忆能力减退,其机制可能与降低海马组织中TNF-α,IL-1β,NO...     

Impairment of the spatial learning and memory induced by learned helplessness and chronic mild stress

Increasing evidences indicate the concurrence and interrelationship of depression and cognitive impairments. The present study was undertaken to investigate the effects of two depressive animal models, learned helplessness (LH) and chronic mild stress (CMS), on the cognitive functions of mice in the Morris water maze task. Our results demonstrated that both LH and CMS significantly decreased the cognitive performance of stressed mice in the water maze task. The escaping latency to the platform was prolonged and the probe test percentage in the platform quadrant was reduced. These two models also increased the plasma corticosterone concentration and decreased the brain derived neurotrophic factor (BDNF) and cAMP-response element-biding protein (CREB) messenger ribonucleic acid (mRNA) levels in hippocampus, which might cause the spatial cognition deficits. Repeated treatment with antidepressant drugs, imipramine (Imi) and fluoxetine (Flu), significantly reduced the plasma corticosterone concentration and enhanced the BDNF and CREB levels. Furthermore, antidepressant treated animals showed an ameliorated cognitive performance compared with the vehicle treated stressed animals. These data suggest that both LH and CMS impair the spatial cognitive function and repeated treatment with antidepressant drugs decreases the prevalence of cognitive impairments induced by these two animal models. Those might in part be attributed to the reduced plasma corticosterone and enhanced hippocampal BDNF and CREB expressions. This study provided a better understanding of molecular mechanisms underlying interactions of depression and cognitive impairments, although animal models used in this study can mimic only some aspects of depression or cognition of human.     

Equipotent inhibition by R(-)-, S(+)- and racemic ibuprofen of human polymorphonuclear cell function in vitro.

1. The effects of racemic (rac) ibuprofen and its S(+)- and R(-)-enantiomers on functions of human polymorphonuclear cells (PMN) and platelets were studied in vitro. 2. Rac-ibuprofen inhibited PMN functions (O2- generation, beta-glucuronidase release, LTB4 formation). Similar IC50 values (40-100 microM) were obtained for the S(+)- and R(-)-enantiomers. 3. All forms of ibuprofen inhibited cyclooxygenase-related platelet functions (aggregation, thromboxane formation). The S(+)-enantiomer was about twice as active as the racemate while the R(-)-enantiomer was at least 10-fold less active. This demonstrates that the S(+) is the only cyclooxygenase inhibitory component of the racemate. 4. The concentrations of rac-ibuprofen in PMN and platelets were similar to those in the incubation medium and represented equal concentrations of the enantiomers. This indicates that neither interconversion nor tissue accumulation of the compounds occurred. 5. These data indicate that antineutrophil effects of ibuprofen on human PMN are independent of cyclooxygenase inhibition. Therefore, R(-)-ibuprofen may be superior to the S(+)-isomer for the treatment of PMN-dependent inflammatory diseases. However, effective free drug concentrations may not be obtained in vivo.     

Evaluating the effects of single and combined chelators therapies on spatial learning and memory impairments in chronic manganese poisoning

Manganese (Mn) is considered an essential metal; nevertheless, exposure to high levels of Mn may cause neurotoxic effects. In the present study, we examined the effect of Mn on spatial learning and memory impairment and ability of three known chelators deferasirox (DFX), deferiprone (L1) and desferrioxamine (DFO) as single and combined therapies in removing Mn from the body and their effect on spatial learning and memory in rats poisoned with manganese. Male Wistar rats divided to 19 groups (5 rats per group). Two doses of manganese chloride (30 and 60?mg/kg/b.w. in drinking water) were administrated for 90 days. Then chelators were given for 14 days. Results showed that exposure to Mn (high and low doses) significantly impaired the spatial learning and memory compared to control group (p?<?0.01). Chelation therapy improved it in chelator agents groups compared to vehicle group (p?<?0.001). Chelator agents with removing Mn from brain can improve MWM performance. Results indicated that combined therapies were more efficient compared to single therapies.     

Dehydroevodiamine attenuates tau hyperphosphorylation and spatial memory deficit induced by activation of glycogen synthase kinase-3 in rats

Tau hyperphosphorylation and memory deficit are characteristic alterations of Alzheimer's disease (AD), and glycogen synthase kinase-3 (GSK-3) plays a crucial role in these AD-like changes. We have reported that activation of GSK-3 through ventricular injection of wortmannin and GF-109203X (WT/GFX, 100 microM each) induces tau hyperphosphorylation and memory impairment of rats [Liu, S.J. et al., 2003. Overactivation of glycogen synthase kinase-3 by inhibition of phosphoinositol-3 kinase and protein kinase C leads to hyperphosphorylation of tau and impairment of spatial memory. J. Neurochem. 87, 1333-1344]. By using this model, we explored in the present study the effects of dehydroevodiamine (DHED), a quinazoline alkaloid isolated from Evodia rutaecarpa Bentham, on the memory retention, tau phosphorylation and the activity of GSK-3. We found that pre-administration of DHED through vena caudalis for 1 week efficiently improved the WT/GFX-induced spatial memory retention impairment of the rats; it also antagonized tau hyperphosphorylation at multiple AD sites and arrested the overactivation of GSK-3 induced by WT/GFX. Our study gave the first in vivo evidence that DHED could suppress the overactivation of GSK-3 and improve tau hyperphosphorylation and spatial memory deficit of the rats, suggesting that this chemical may be served as a candidate for arresting AD-like pathological and behavioral alterations.     

The effect of food or sucralfate on the bioavailability of S(+) and R(-) enantiomers of ibuprofen.

This randomized, multiple cross-over pharmacokinetic study was undertaken to determine if food or sucralfate alter the bioavailability of the active S(+) enantiomer of ibuprofen. Eleven healthy adult male volunteers were given three single 600-mg doses of ibuprofen (separated by 1 week) administered either in a fasting state, after a standardized breakfast, or with sucralfate 1 g. The main outcome measures were area under the concentration (AUC), maximum peak plasma concentration (Cmax), and time to reach peak concentration (tmax) for total, S(+), and R(-) enantiomer serum ibuprofen levels, drawn up to 10 hours after dosing. The AUC for R(-) ibuprofen was significantly lower than S(+) ibuprofen in all three treatment groups. The treatments had no different effects on AUC for S(+), R(+), or total ibuprofen. There was no difference in the ratio of S(+):R(-) enantiomers across different treatment groups, but the intersubject variability was significant (P < .05). The S(+) ibuprofen Cmax was greater than the R(-) ibuprofen Cmax for all treatment groups (P < .05). Sucralfate reduced the peak concentration of both S(+) and R(-) enantiomers when compared with fasting (P < .05). There was a slight but nonsignificant increase in the mean time to achieve peak concentration of both S(+) and R(-) enantiomers. Neither food nor sucralfate has a significant effect on ibuprofen enantiomer pharmacokinetics, but interindividual variability contributes significantly to the variability of enantiomer bioavailability.     

Serotonin (5-HT) precursor loading with 5-hydroxy-l-tryptophan (5-HTP) reduces locomotor activation produced by (+)-amphetamine in the rat

BackgroundFew studies have differentiated between independent and substance-induced psychiatric disorders. In this study we determine the risks associated with independent and substance-induced psychiatric disorders among a sample of 629 illicit drug users recruited from treatment and out of treatment settings.MethodsSecondary analysis of five cross-sectional studies conducted during 2000–2006. Independent and substance-induced DSM-IV psychiatric diagnoses were assessed using the Psychiatric Research Interview for Substance and Mental Disorders.ResultsLifetime prevalence of Axis I disorders other than substance use disorder (SUD) was 41.8%, with independent major depression being the most prevalent (17%). Lifetime prevalence of antisocial or borderline personality disorders was 22.9%. In multinominal logistic regression analysis (SUD only as the reference group), being female (OR 2.45; 95% CI 1.59, 3.77) and having lifetime borderline personality disorder (OR 2.45; 95% CI 1.31, 4.59) remained significant variables in the group with independent disorders. In the group with substance-induced disorders, being recruited from an out of treatment setting (OR 3.50; 95% CI 1.54, 7.97), being female (OR 2.38; 95% CI 1.24, 4.59) and the number of SUD (OR 1.31; 95% CI 1.10, 1.57) remained significant in the model. These variables were also significant in the group with both substance-induced and independent disorders, together with borderline personality disorder (OR 2.53; 95% CI 1.03, 6.27).ConclusionsIllicit drug users show high prevalence of co-occurrence of mainly independent mood and anxiety psychiatric disorders. Being female, recruited from an out of treatment setting and the number of SUD, are risk factors for substance-induced disorders.     

Mephedrone (4-methylmethcathinone) and d-methamphetamine improve visuospatial associative memory,but not spatial working memory,in rhesus macaques

BACKGROUND AND PURPOSE

The novel cathinone derivative 4-methylmethcathinone (4-MMC; mephedrone) is increasingly popular with recreational users. Little scientific information is available but users report both entactogen-like and classic stimulant-like subjective properties. A recent study in humans reported psychomotor speed improvement after intranasal 4-MMC suggesting classic stimulant properties. Limitations of the user group (which was impaired on some tasks) prompt controlled laboratory investigation.

EXPERIMENTAL APPROACH

Adult male rhesus monkeys were trained to perform tasks from the non-human primate Cambridge Neuropsychological Test Automated Battery, which assess spatial working memory, visuospatial associative memory, learning and motivation for food reward. Test of bimanual motor coordination and manual tracking were also included. The subjects were challenged with 0.178–0.56 mg·kg⁻¹ 4-MMC and 0.056–0.56 mg·kg⁻¹ d-methamphetamine (MA), i.m., in randomized order for behavioural evaluation.

KEY RESULTS

A pronounced improvement in visuospatial memory and learning was observed after the 0.32 mg·kg⁻¹ dose of each compound, this effect was confirmed with subsequent repetition of these conditions. Spatial working memory was not improved by either drug, and the progressive ratio, bimanual motor and rotating turntable tasks were all disrupted in a dose-dependent manner.

CONCLUSIONS AND IMPLICATIONS

These studies show that 4-MMC produces behavioural effects, including improvements in complex spatial memory and learning that are in large part similar to those of MA in non-human primates. Thus, the data suggest that the effects of 4-MMC in monkeys can be classified with classical psychomotor stimulants.     

Histidine enhances carbamazepine action against seizures and improves spatial memory deficits induced by chronic transauricular kindling in rats

AIM：To investigate whether histidine can enhance the anticonvulsant efficacy of carbamazepine （CBZ） and simultaneously improve the spatial memory impairment induced by transauricular kindled seizures in Sprague-Dawley rats. METHODS： Chronic transauricular kindling was induced by repeated application of initially subconvulsive electrical stimulation through ear-clip electrodes once every 24 h until the occurrence of three consecutive clonic-tonic seizures. An 8 - arm radial maze （ 4 arms baited） was used to measure spatial memory,     

Histidine enhances carbamazepine action against seizures and improves spatial memory deficits induced by chronic transauricular kindling in rats

AIM: To investigate whether histidine can enhance the anticonvulsant efficacy of carbamazepine (CBZ) and simultaneously improve the spatial memory impairment induced by transauricular kindled seizures in Sprague-Dawley rats. METHODS: Chronic transauricular kindling was induced by repeated application of initially subconvulsive electrical stimulation through ear-clip electrodes once every 24 h until the occurrence of 3 consecutive clonic-tonic seizures. An 8-arm radial maze (4 arms baited) was used to measure spatial memory, and histamine and gamma-amino-butyric acid levels were measured by high performance liquid chromatography (HPLC). RESULTS: Chronic transauricular kindling produced a significant impairment of spatial memory and a marked decrease in histamine content in the hypothalamus, the brainstem, and the hippocampus. Injection of histidine (1000 mg/kg or 1500 mg/kg, ip) significantly inhibited transauricular kindled seizures. Injection of histidine at lower doses (200 mg/kg or 500 mg/kg, ip) had no appreciable anticonvulsant effect when administered alone, whereas it significantly potentiated the protective effects of CBZ against kindled seizures. CBZ had no ameliorative effect on memory deficit, but, in contrast, histidine (200 mg/kg or 500 mg/kg, ip) alone or co-administered with CBZ significantly ameliorated the memory deficits induced by the seizures. CONCLUSION: Chronic transauricular kindling is a very useful animal model for evaluating memory deficits associated with epilepsy, and histidine has both a potentiate effect on the anticonvulsant efficacy of CBZ and an ameliorative effect on the spatial memory deficits induced in this model. Histidine at a specific dosage range might serve as a beneficial adjuvant for the clinical treatment of epilepsy, especially when accompanied by impaired spatial memory.     

Improvement by nefiracetam of beta-amyloid-(1-42)-induced learning and memory impairments in rats

1. We have previously demonstrated that continuous i.c.v. infusion of amyloid beta-peptide (A beta), the major constituent of senile plaques in the brains of patients with Alzheimer's disease, results in learning and memory deficits in rats. 2. In the present study, we investigated the effects of nefiracetam [N-(2,6-dimethylphenyl)-2-(2-oxo-1-pyrrolidinyl) acetamide, DM-9384] on A beta-(1-42)-induced learning and memory deficits in rats. 3. In the A beta-(1-42)-infused rats, spontaneous alternation behaviour in a Y-maze task, spatial reference and working memory in a water maze task, and retention of passive avoidance learning were significantly impaired as compared with A beta-(40-1)-infused control rats. 4. Nefiracetam, at a dose range of 1-10 mg kg(-1), improved learning and memory deficits in the A beta-(1-42)-infused rats when it was administered p.o. 1 h before the behavioural tests. 5. Nefiracetam at a dose of 3 mg kg(-1) p.o. increased the activity of choline acetyltransferase in the hippocampus of A beta-(1-42)-infused rats. 6. Nefiracetam increased dopamine turnover in the cerebral cortex and striatum of A beta-(1-42)-infused rats, but failed to affect the noradrenaline, serotonin and 5-hydroxyindoleacetic acid content. 7. These results suggest that nefiracetam may be useful for the treatment of patients with Alzheimer's disease.     

慢性应激和脂多糖构建昆明种小鼠抑郁症动物模型

目的 利用慢性不可预见性温和应激(chronic unpredictable mild stress,CUMS)联合脂多糖(lipopolysaccharide,LPS)构建稳定的抑郁症动物模型.方法 雄性昆明种小鼠48只分为正常对照组、LPS 组(LPS 0.2 mg·kg-1,i.p.)、CUMS 组(CUMS+生...     

Effects of acetyl salycilic acid and ibuprofen in chronic liver damage induced by CCl4

Non-steroidal anti-inflammatory drugs (NSAIDs) are drugs used primarily to treat inflammation, pain and fever. Their main mechanism of action is cyclooxygenase (COX) inhibition, and this enzyme has been linked to hepatotoxicity. The association of COX and liver injury has been, in part, due to the presence of COX-2 isoform in damaged liver and the possible induction of this enzyme by profibrotic molecules like Transforming Growth Factor-β (TGF-β). The aim of this work was to evaluate the effects of two of the most used NSAIDs, acetyl salicylic acid (ASA) and ibuprofen (IBP), on experimental liver fibrosis. We formed experimental groups of rats including vehicle and drug controls, damage induced by chronic CCl4 (0.4 g kg(-1) , i.p., three times per week, for 8 weeks) administration, and CCl4 plus ASA (100 mg kg(-1) , p.o., daily) or IBP (30 mg kg(-1) , p.o., daily). Both drugs showed important antifibrotic properties. They inhibited COX-2 activity, prevented oxidative stress measured as lipid peroxidation and glutathione content, and ASA inhibited partially and IBP totally increased TGF-β expression and collagen content. ASA and IBP prevented translocation of NFκB to the nucleus and, interestingly, ASA induced MMP-2 and MMP-13 whereas IBP induced MMP-2, MMP-9 and MMP-13. As a whole, these effects explain the beneficial effects of ASA and IBP on experimental liver fibrosis.     

Cholinergic agents: Deficits in rat hippocampal choline acetyltransferase activity and spatial working memory induced by intracerebroventricular administration of stoichiometrically prepared 1-ethyl-1-(2-hydroxyethyl) aziridinium ion (AF64A)

A simplified procedure for preparing the cholinergic neurotoxin 1-ethyl-1-(2-hydroxyethyl) aziridinium ion (AF64A) is reported that employs stoichiometric base. When injected intracerebroventricularly into rats, stoichiometrically prepared AF64A causes impairments in spatial working memory in a water-maze task. The behavioral changes are paralleled by deficits in hippocampal choline acetyltransferase activity, a neurochemical marker of the resulting cholinergic dysfunction.     

Minaprine improves impairment of working memory induced by scopolamine and cerebral ischemia in rats

Using a repeated acquisition procedure in a three-panel runway apparatus, the effects of minaprine on the impairment of working memory produced by scopolamine, ethylcholine aziridinium ion (AF64A) or cerebral ischemia were investigated in rats. Minaprine (3.2–32 mg/kg IP) as well as idebenone (10–100 mg/kg IP) and physostigmine (0.1–0.32 mg/kg IP) dose-dependently reduced the increase of errors (pushes made on the two incorrect panels located at each choice point) induced by 0.56 mg/kg IP scopolamine. Cerebral ischemia for 5 min caused a significant increase of errors in the runway task. Minaprine at 3.2 and 10 mg/kg administered IP immediately after blood recirculation and again 30 min before the runway test conducted 24 h after ischemia, significantly reduced increases in errors expected to occur after 5 min of ischemia. Physostigmine 0.1 mg/kg similarly attenuated the increase in errors in ischemic rats. However, minaprine at doses up to 32 mg/kg IP failed to reduce the increase of errors induced by AF64A 2.5 nmol injected into the dorsal hippocampus. These findings suggest that minaprine exerts an ameliorating effect on amnesia produced by scopolamine and cerebral ischemia, probably through mediation of its stimulant action on central cholinergic systems.     

Low dose of 1,3-di(2-tolyl)guanidine (DTG) attenuates MK-801-induced spatial working memory impairment in mice

MK-801 (30–100 µg/kg, SC) impaired spontaneous alternation behavior of mice, a behavior related to the spatial working memory. 1,3-Di-(2-tolyl)guanidine (DTG),(+)-pentazocine and (+)-SKF 10,047 (100 µg/kg, SC), putative agonists, administered 10 min before MK-801, partially but significantly reversed the impairment, without affecting the concomitant hyperlocomotion. The antagonizing effects by DTG were prevented by BMY-14802 (5 mg/kg, IP), a purported antagonist. These findings suggest that, at low doses, ligands may modulate theN-methyl-d-aspartate dependent memory processes.