Breast cancer surgery decreases serum brain-derived neurotrophic factor concentrations in middle aged women: relationship to the serum C-reactive protein concentration.

The aim of this study was to establish the effect of breast cancer surgery in middle aged women on the serum (s) and plasma (p) brain-derived neurotrophic factor concentrations [BDNF]s and [BDNF]p, respectively, in relation to the serum C-reactive protein [CRP]s concentration measured before and at 24 hours after surgery. Eighteen patients with recently diagnosed breast cancer (mean ± SE): age 49.1 ± 1.6 years, body mass 69.8 ± 2.2 kg, BMI 25.8 ± 0.8 kg m-2, participated in this study. The [BDNF]s before the surgery amounted to 25 523 ± 1 416 pg ml-1. At 24 h after the surgery it decreased to 21 551 ± 998 pg ml-1 (P = 0.004). This decrease was accompanied by a significant (P = 0.001) decrease in the platelet count (PLT) from 254.7 ± 12.2 k µl-1 before, to 228.8 ± 9.7 k µl-1 after the surgery. The [CRP]s increased from 3.59 ± 0.79 mg l-1 before to 25.04 ± 4.65 mg l-1 after the surgery (P = 0.002). A significant positive correlation was found between the [BDNF]s and the PLT both before (P = 0.003) as well as after the surgery (P = 0.027). Moreover, a significant positive correlation (P = 0.046) was found between [BDNF]s and the [CRP] s before the surgery. At 24 h after the surgery the [BDNF]s and the [CRP]s still correlated positively (P = 0.044), despite the fact that the surgery significantlly decresed the [BDNF]s and increased [CRP]s. No significant effect of the surgery on the [BDNF]p was found. We have concluded that serum BDNF concentration in breast cancer patients positively correlates with serum CRP both before and at 24 h after the surgery. Moreover, breast cancer surgery decreases serum BDNF concentration at 24 h after operation and increases [CRP]s.

Comparative effectiveness of abatacept, apremilast, secukinumab and ustekinumab treatment of psoriatic arthritis: a systematic review and network meta-analysis.

To assess the comparative effectiveness and safety of novel biologic therapies in psoriatic arthritis (PsA) and to establish the position of the non-anti-tumor necrosis factor α (TNF-α) biologic drugs in the treatment regimen of the disease. A systematic review and network meta-analysis (NMA) was conducted according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) requirements. Two investigators identified the studies, abstracted data, and assessed the risk of bias independently. The NMA was conducted for efficacy [American College of Rheumatology (ACR) criteria, ACR20 and ACR50; psoriasis area and severity index (PASI), PASI75] and safety outcomes [any adverse events (AEs) and serious adverse events (SAEs)]; treatments were ranked using the P score for each outcome. The PROSPERO registration number was 42017072200. MEDLINE/PubMed, Embase, Cochrane Library, and ClinicalTrials.gov were searched from the inception of each database to July 10, 2017. Randomized controlled trials (RCTs) for abatacept, apremilast, secukinumab or ustekinumab in adults with moderate and severe PsA were included. The overall PsA population and anti-TNF-α-naive, anti-TNF-α-failure, or anti-TNF-α-experienced subpopulations were considered. We identified eight eligible RCTs and included them in the systematic review and NMA. Significant differences in ACR20 response rate were revealed between secukinumab 150 mg and apremilast 20 mg [relative risk; RR = 2.55 (CI-confidence interval; 1.24, 5.23)] and between secukinumab 300 mg and apremilast 20 or 30 mg [RR = 3.57 CI (1.48, 8.64) and RR = 2.84 CI (1.18, 6.86), respectively]. Any AEs occurred more often in apremilast 20 and 30 mg compared with placebo [RR = 0.58 CI (0.45, 0.74) and RR = 0.58 CI (0.45, 0.75), respectively] but also compared with secukinumab 150 mg [RR = 0.54 CI (0.35, 0.81) and RR = 0.45 CI (0.35, 0.82), respectively]. No significant differences were revealed for SAEs among biologics and between biologics and placebo. In the overall population, as well as in the anti-TNF-α-naive subpopulation, secukinumab at a dose of 300 and 150 mg was ranked the highest for the ACR20 endpoint, while in the anti-TNF-α-experienced subpopulation, secukinumab 300 mg and apremilast 30 mg revealed the highest rank. Secukinumab 75 mg was the safest drug in terms of any AEs, but for SEAs the safest was ustekinumab 90 mg. Our study revealed no significant differences among non-anti-TNF-α biologics in the treatment of PsA in the comparisons performed with regards to the highest efficacy and safety. Both in the overall population and in the analyzed subpopulations, secukinumab 300 mg was ranked the highest for the ACR20 response rate. Secukinumab 300 mg was the safest drug in terms of any AEs, and ustekinumab 90 mg presented the lowest overall risk of SAEs. Head-to-head trials and evaluation of comparative efficacy and safety between non-TNF-α biologics are warranted to inform clinical decision making with a relevant treatment paradigm.

Decreased sensitivity to paroxetine-induced inhibition of peripheral blood mononuclear cell growth in depressed and antidepressant treatment-resistant patients.

Major depression disorder (MDD) is the most widespread mental disorder. Selective serotonin reuptake inhibitors (SSRIs) are used as first-line MDD treatment but are effective in <70% of patients. Thus, biomarkers for the early identification of treatment-resistant (TR) MDD patients are needed for prioritizing them for alternative therapeutics. SSRI-induced inhibition of the growth of peripheral blood mononuclear cells (PBMCs) is mediated via their target, the serotonin transporter (SERT). Here, we examined whether antidepressant drug-induced inhibition of the growth of PBMCs differed between MDD patients and healthy controls. PBMCs from well-characterized 33 treatment-sensitive (TS) and 33 TR MDD patients, and 24 healthy volunteers were studied. Dose-dependent inhibition of PBMCs growth was observed for both the non-SSRI antidepressant mirtazapine and the SSRI antidepressant paroxetine. Significantly lower sensitivities to 20 µm paroxetine were observed in MDD compared with control PBMCs prior to treatment onset (13% and 46%, respectively; P<0.05). Following antidepressant drug treatment for 4 or 7 weeks, the ex vivo paroxetine sensitivity increased to control levels in PBMCs from TS but not from TR MDD patients. This suggests that the low ex vivo paroxetine sensitivity phenotype reflects a state marker of depression. A significantly lower expression of integrin beta-3 (ITGB3), a co-factor of the SERT, was observed in the PBMCs of MDD patients prior to treatment onset compared with healthy controls, and may explain their lower paroxetine sensitivity. Further studies with larger cohorts are required for clarifying the potential of reduced PBMCs paroxetine sensitivity and lower ITGB3 expression as MDD biomarkers.

Neuroprotective effects of mGluR II and III activators against staurosporine- and doxorubicin-induced cellular injury in SH-SY5Y cells: New evidence for a mechanism involving inhibition of AIF translocation.

There are several experimental data sets demonstrating the neuroprotective effects of activation of group II and III metabotropic glutamate receptors (mGluR II/III), however, their effect on neuronal apoptotic processes has yet to be fully recognized. Thus, the comparison of the neuroprotective potency of the mGluR II agonist LY354740, mGluR III agonist ACPT-I, mGluR4 PAM VU0361737, mGluR8 PAM AZ12216052 and allosteric mGluR7 agonist AMN082 against staurosporine (St-) and doxorubicin (Dox)-induced cell death has been performed in undifferentiated (UN-) and retinoic acid differentiated (RA-) human neuroblastoma SH-SY5Y cells. The highest neuroprotection in UN-SH-SY5Y cells was noted for AZ12216052 (0.01-1 µM) and VU0361737 (1-10 µM), with both agents partially attenuating the St- and Dox-evoked cell death. LY354740 (0.01-10 µM) and ACPT-I (10 µM) were protective only against the St-evoked cell damage, whereas AMN082 (0.001-0.01 µM) attenuated only the Dox-induced cell death. In RA-SH-SY5Y, a moderate neuroprotective response of mGluR II/III activators was observed for LY354740 (10 µM) and AZ12216052 (0.01 and 10 µM), which afforded protection only against the St-induced cell damage. The protection mediated by mGluR II/III activators against the St- and Dox-evoked cell death in UN-SH-SY5Y cells was not related to attenuation of caspase-3 activity, however, a decrease in the number of TUNEL-positive nuclei was found. Moreover, mGluR II/III activators attenuated the cytosolic level of the apoptosis inducing factor (AIF), which was increased after St and Dox exposure. Our data point to differential neuroprotective efficacy of various mGluR II/III activators in attenuating St- and Dox-evoked cell damage in SH-SY5Y cells, and dependence of the effects on the cellular differentiation state, as well on the type of the pro-apoptotic agent that is employed. Moreover, the neuroprotection mediated by mGluR II/III activators is accompanied by inhibition of caspase-3-independent DNA fragmentation evoked by AIF translocation.

Are pharmacological properties of anticoagulants reflected in pharmaceutical pricing and reimbursement policy? Out-patient treatment of venous thromboembolism and utilization of anticoagulants in Poland.

OBJECTIVES: Pharmacotherapy with vitamin K antagonists (VKA) and low-molecular-weight heparins (LMWH) is a major cost driver in the treatment of venous thromboembolism (VTE). Major representatives of anticoagulants in Europe include: acenocoumarol and warfarin (VKA), enoxaparin, dalteparin, nadroparin, reviparin, parnaparin and bemiparin (LMWH). Aim of this report is to measure and critically assess the utilization of anticoagulants and other resources used in the out-patient treatment of VTE in Poland. To confront the findings with available scientific evidence on pharmacological and clinical properties of anticoagulants. MATERIALS AND METHODS: The perspectives of the National Health Fund (NHF) and the patients were adopted, descriptive statistics methods were used. The data were gathered at the NHF and the clinic specialized in treatment of coagulation disorders. RESULTS: Non-pharmacological costs of treatment were for the NHF 1.6 times higher with VKA than with LMWH. Daily cost of pharmacotherapy with LMWH turned out higher than with VKA (234 times for the NHF, 42 times per patient). Within both LMWH and VKA the reimbursement due for the daily doses of a particular medication altered in the manner inversely proportional to the level of patient co-payment. Utilization of long-marketed and cheap VKA was dominated by LMWH, when assessed both through the monetary measures and by the actual volume of sales. Pharmaceutical reimbursement policy favored the more expensive equivalents among VKA and LMWH, whereas in the financial terms the patients were far better off when remaining on a more expensive alternative. CONCLUSIONS: The pharmaceutical pricing and reimbursement policy of the state should be more closely related to the pharmacological properties of anticoagulants.

Neuroprotective effects of metabotropic glutamate receptor group II and III activators against MPP(+)-induced cell death in human neuroblastoma SH-SY5Y cells: the impact of cell differentiation state.

Recent studies have documented that metabotropic glutamate receptors from group II and III (mGluR II/III) are a potential target in the symptomatic treatment of Parkinson's disease (PD), however, the neuroprotective effects of particular mGluR II/III subtypes in relation to PD pathology are recognized only partially. In the present study, we investigated the effect of various mGluR II/III activators in the in vitro model of PD using human neuroblastoma SH-SY5Y cell line and mitochondrial neurotoxin MPP(+). We demonstrated that all tested mGluR ligands: mGluR II agonist - LY354740, mGluR III agonist - ACPT-I, mGluR4 PAM - VU0361737, mGluR8 agonist - (S)-3,4-DCPG, mGluR8 PAM - AZ12216052 and mGluR7 allosteric agonist - AMN082 were protective against MPP(+)-evoked cell damage in undifferentiated (UN-) SH-SY5Y cells with the highest neuroprotection mediated by mGluR8-specific agents. However, in retinoic acid- differentiated (RA-) SH-SY5Y cells we found protection mediated only by mGluR8 activators. We also demonstrated the cell proliferation stimulating effect for mGluR4 and mGluR8 PAMs. Next, we showed that the protection mediated by mGluR II/III activators in UN-SH-SY5Y was not accompanied by the modulation of caspase-3 activity, however, a decrease in the number of apoptotic nuclei was found. Finally, we showed that the inhibitor of necroptosis, necrostatin-1 blocked the mGluR III-mediated protection. Altogether our comparative in vitro data add a further proof to neuroprotective effects of mGluR agonists or PAMs and point to mGluR8 as a promising target for neuroprotective interventions in PD. The results also suggest the participation of necroptosis-related molecular pathways in neuroprotective effects of mGluR III activation.

The reversal of cognitive, but not negative or positive symptoms of schizophrenia, by the mGlu2/3 receptor agonist, LY379268, is 5-HT1A dependent.

mGlu(2/3) receptor agonists were shown to possess an antipsychotic-like potential in animal studies. Recent clinical investigations revealed that their antipsychotic potential might also manifest in humans. LY379268, the group II mGlu receptor orthosteric agonist, was previously shown to exhibit antipsychotic-like action in animal models of schizophrenia. However, the mechanism of its action is not fully recognized. Here, we decided to investigate the involvement of 5-HT1A receptors in the LY379268-induced antipsychotic effects. We used models of positive, negative and cognitive symptoms of schizophrenia, such as MK-801- and amphetamine-induced hyperactivity tests, DOI-induced head twitches, social interaction and novel object recognition. LY379268 was active in a wide range of doses (0.5-5 mg/kg), depending on the paradigm. The effects of the drug were not antagonized by 5-HT(1A) antagonist, WAY100635 (0.1 mg/kg) in the models of positive and negative symptoms. Conversely, in the novel object recognition test, which exerts cognitive disturbances, the action of LY379268 was antagonized by WAY100635. Concomitantly, the action of a sub-effective dose of the drug was enhanced by the administration of a sub-effective dose of 5-HT(1A) agonist, (R)-(+)-8-Hydroxy-DPAT. Altogether, we propose that the antipsychotic-like action of group II mGlu receptors' agonist is 5-HT(1A) independent in context of positive and negative symptoms, while the action toward cognitive disturbances seems to be 5-HT(1A) dependent.

On the mechanism of anti-hyperthermic effects of LY379268 and LY487379, group II mGlu receptors activators, in the stress-induced hyperthermia in singly housed mice.

Earlier studies have demonstrated that the agonists of the mGlu(2/3) receptors produced anxiolytic actions after peripheral administration. However, the mechanism of their action is still not clear. Therefore the aim of the present study was to specify the role of the GABAergic and serotonergic system in the mechanism of the anxiolytic activity of group II mGlu receptor activators by using the stress induced hyperthermia test (SIH) in singly housed mice. We used an orthosteric mGlu(2/3) receptor agonist, LY379268, which induced anti-hyperthermic efficacy in the doses of 1-5mg/kg (73% of inhibition after a highest dose). The effect of the second ligand used, a mGlu(2) receptor positive modulator (PAM), LY487379, was observed in a dose range of 0.5-5mg/kg and reached 53% of the inhibition. The blockade of GABAergic system by GABA(A) receptor antagonist flumazenil (10mg/kg) or GABA(B) receptor antagonist CGP55845 (10mg/kg), and the blockade of serotonergic system by 5-HT(1A) receptor antagonist WAY100635 (0.1 and 1mg/kg) or 5-HT(2A/2C) receptor antagonist ritanserin (0.5mg/kg) had no influence on the anti-hyperthermic effect induced by effective dose of LY379268. However, the action of the effective dose of LY487379 was enhanced when co-administered with flumazenil, WAY100635 (0.1mg/kg) and ritanserin. Similar results were observed for the subeffective dose of LY379268 (0.5mg/kg). WAY100635 in a dose of 1mg/kg did not induce any enhancing effect on the activity of compounds. Therefore, it seems that the antagonism towards GABA(A) receptors, presynaptic 5-HT(1A) and postsynaptic 5-HT(2A/2C) receptors is responsible for the phenomenon. This article is part of a Special Issue entitled 'Anxiety and Depression'.

The GABA B receptor agonist CGP44532 and the positive modulator GS39783 reverse some behavioural changes related to positive syndromes of psychosis in mice.

BACKGROUND AND PURPOSE: An important role of GABAergic neurotransmission in schizophrenia was proposed a long time ago, but there is limited data to support this hypothesis. In the present study we decided to investigate GABA(B) receptor ligands in animal models predictive for the antipsychotic activity of drugs. The GABA(B) receptor antagonists CGP51176 and CGP36742, agonist CGP44532 and positive allosteric modulator GS39783 were studied. EXPERIMENTAL APPROACH: The effects of all ligands were investigated in MK-801- and amphetamine-induced hyperactivity tests. The anti-hallucinogenic-like effect of the compounds was screened in the model of head twitches induced by (±)1-(2.5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI). Furthermore, the effect of GS39783 and CGP44532 on DOI-induced frequency of spontaneous excitatory postsynaptic currents (EPSCs) in slices from mouse brain frontal cortices was investigated. The anti-cataleptic properties of the compounds were also assessed. KEY RESULTS: The GABA(B) receptor activators CGP44532 and GS39783 exhibited antipsychotic-like effects both in the MK-801- and amphetamine-induced hyperactivity tests, as well as in the head-twitch model in mice. Such effects were not observed for the GABA(B) receptor antagonists. DOI-induced increased frequency of spontaneous EPSCs was also decreased by the compounds. Moreover, CGP44532 and GS39783 inhibited haloperidol-induced catalepsy and EPSCs. CONCLUSION AND IMPLICATIONS: These data suggest that selective GABA(B) receptor activators may be useful in the treatment of psychosis.

The effect of physical activity on the brain derived neurotrophic factor: from animal to human studies.

It is well documented that physical activity can induce a number of various stimuli which are able to enhance the strength and endurance performance of muscles. Moreover, regular physical activity can preserve or delay the appearance of several metabolic disorders in the human body. Physical exercise is also known to enhance the mood and cognitive functions of active people, although the physiological backgrounds of these effects remain unclear. In recent years, since the pioneering study in the past showed that physical activity increases the expression of the brain derived neurothophic factor (BDNF) in the rat brain, a number of studies were undertaken in order to establish the link between that neurothrophin and post-exercise enhancement of mood and cognitive functions in humans. It was recently demonstrated that physical exercise can increase plasma and/or serum BDNF concentration in humans. It was also reported that physical exercise or electrical stimulation can increase the BDNF expression in the skeletal muscles. In the present review, we report the current state of research concerning the effect of a single bout of exercise and training on the BDNF expression in the brain, in both the working muscles as well as on its concentrations in the blood. We have concluded that there may be potential benefits of the exercise-induced enhancement of the BDNF expression and release in the brain as well as in the peripheral tissues, resulting in the improvement of the functioning of the body, although this effect, especially in humans, requires more research.

GABAergic dysfunction in mGlu7 receptor-deficient mice as reflected by decreased levels of glutamic acid decarboxylase 65 and 67kDa and increased reelin proteins in the hippocampus.

Glutamate is the main excitatory neurotransmitter in the brain, while gamma-aminobutyric acid (GABA) is a primary inhibitory neuromodulator. Both amino acids act through ionotropic and metabotropic receptors that are widely distributed in the central nervous system. There are at least eight subtypes of metabotropic glutamate receptors (mGlu), which have been divided into three groups (mGlu I, II, and III). The mGlu7 receptor subtype, which belongs to the mGlu III group, seems to play a special role, as it is abundant in brain structures that are known to be responsible for antidepressant and/or anxiolytic activity of drugs. In GABAergic neurons, GABA is synthesised from glutamate by the pyridoxal phosphate (PLP)-dependent enzyme glutamic acid decarboxylase (GAD). It is expressed as two major isoforms, GAD65 and GAD67, responsible for the synthesis of the vesicular and cytoplasmic pool of neurotransmitter, respectively. Moreover, GABAergic neurons express a variety of proteins such as reelin, involved in synaptic transmission and plasticity. The aim of our study was to investigate the regulation of GABA synthesis and the level of modulatory receptor for GABA in mice lacking mGlu7 receptor for glutamate. The levels of GAD mRNA, GADs, and reelin proteins in the hippocampi of mGlu7-/- and mGlu7-/+ mice were measured using in situ hybridisation, immunohistochemistry, and Western blotting (WB). GAD mRNAs in the CA and DG regions of the hippocampus were measured separately. The levels of GAD65, GAD67, and reelin proteins were determined in the homogenates using WB, and the number of stained neurons was estimated using a stereological method of counting. GABA(B) receptor level was measured using a radioligand binding assay. Our results show that the mRNA and protein levels of both GADs were decreased in the hippocampi of animals lacking the mGlu7 receptor. Decreased levels of GAD67 mRNA were found in both the CA and DG regions, while the decrease in GAD65 mRNA was observed mainly in the CA region of the hippocampus. The protein levels of GAD65 was lowered in mGlu7-/- animals only, while GAD67 and GABA(B) receptor number were decreased in both mGlu7+/- and mGlu7-/- mice when measured in the whole hippocampus. In contrast, reelin was shown to be increased both in mGlu7-/+ and mGlu7-/- mice. The results suggest that mGlu7 receptor is involved in the regulation of GABAergic system activity at the level of GABA synthesised enzymes, specific proteins expressed by GABAergic neurons and metabotropic receptor for GABA.

The involvement of NMDA and AMPA receptors in the mechanism of antidepressant-like action of zinc in the forced swim test.

Antidepressant-like activity of zinc in the forced swim test (FST) was demonstrated previously. Enhancement of such activity by joint administration of zinc and antidepressants was also shown. However, mechanisms involved in this activity have not yet been established. The present study examined the involvement of the NMDA and AMPA receptors in zinc activity in the FST in mice and rats. Additionally, the influence of zinc on both glutamate and aspartate release in the rat brain was also determined. Zinc-induced antidepressant-like activity in the FST in both mice and rats was antagonized by N-methyl-D-aspartic acid (NMDA, 75 mg/kg, i.p.) administration. Moreover, low and ineffective doses of NMDA antagonists (CGP 37849, L-701,324, D-cycloserine, and MK-801) administered together with ineffective doses of zinc exhibit a significant reduction of immobility time in the FST. Additionally, we have demonstrated the reduction of immobility time by AMPA receptor potentiator, CX 614. The antidepressant-like activity of both CX 614 and zinc in the FST was abolished by NBQX (an antagonist of AMPA receptor, 10 mg/kg, i.p.), while the combined treatment of sub-effective doses of zinc and CX 614 significantly reduces the immobility time in the FST. The present study also demonstrated that zinc administration potentiated a veratridine-evoked glutamate and aspartate release in the rat's prefrontal cortex and hippocampus. The present study further suggests the antidepressant properties of zinc and indicates the involvement of the NMDA and AMPA glutamatergic receptors in this activity.

The group III mGlu receptor agonist ACPT-I exerts anxiolytic-like but not antidepressant-like effects, mediated by the serotonergic and GABA-ergic systems.

Our earlier studies have demonstrated that (1S,3R,4S)-1-aminocyclo-pentane-1,3,4-tricarboxylic acid ACPT-I, a group III mGlu receptor agonist, produced anxiolytic-like and antidepressant-like actions after central administration. Here we describe the anxiolytic-like effects of ACPT-I after intraperitoneal administration in the stress-induced hyperthermia (SIH), elevated plus-maze (PMT) tests in mice and in the Vogel test in rats. However, the compound did not produce antidepressant-like effects in the tail suspension test (TST) or in the forced swim test (FST) in mice. The potential anxiolytic effect of ACPT-I (20 mg/kg) in the SIH test was inhibited by the benzodiazepine receptor antagonist flumazenil (given i.p., 10 mg/kg), and by a 5-HT(1A) receptor antagonist N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridynyl) cyclohexane-carboxamide (WAY100635) (0.1 mg/kg s.c.). At the same time, ritanserin (0.5 mg/kg i.p.), the 5-HT2A/C receptor antagonist, did not change the anxiolytic-like effects of ACPT-I. The results of these studies indicate that the GABA-ergic and serotonergic systems are involved in the potential anxiolytic action of ACPT-I.

Peripheral administration of group III mGlu receptor agonist ACPT-I exerts potential antipsychotic effects in rodents.

Several lines of evidence implicate dysfunction of glutamatergic neurotransmission in the pathophysiology of schizophrenia. Previous behavioral studies have indicated that metabotropic glutamate (mGlu) receptors may be useful targets for the treatment of psychosis. It has been shown that agonists and positive allosteric modulators of group II mGlu receptors produce potential antipsychotic effects in behavioral models of schizophrenia in rodents. Group III mGlu receptors seem to be also promising targets for a variety of neuropsychiatric and neurodegenerative disorders. However, despite encouraging data in animal models, most ligands of group III mGlu receptors still suffer from weak affinities, incapacity to cross the blood-brain barrier or absence of full pharmacological characterization. These limitations slow down the validation process of group III mGlu receptors as therapeutic targets. In this work, we choose to study an agonist of group III mGlu receptors (1S,3R,4S)-1-aminocyclo-pentane-1,3,4-tricarboxylic acid (ACPT-I) using intraperitoneal administration in three animal behavioral models predictive of psychosis or hallucinations. The results of the present study show that ACPT-I, given at doses of 10 or 30mg/kg, decreased MK-801-induced hyperlocomotion and at a dose of 100mg/kg decreased amphetamine-induced hyperlocomotion in rats. Furthermore, ACPT-I dose-dependently decreased DOI-induced head twitches in mice and suppresses DOI-induced frequency and amplitude of spontaneous EPSPs in slices from mouse brain frontal cortices. These data demonstrate that ACPT-I is a brain-penetrating compound and illustrates its promising therapeutic role for the treatment of schizophrenia.

Endurance training increases plasma brain-derived neurotrophic factor concentration in young healthy men.

It is believed that brain derived neurotrophic factor (BDNF) plays an important role in neuronal growth, transmission, modulation and plasticity. Single bout of exercise can increase plasma BDNF concentration [BDNF](p) in humans. It was recently reported however, that elevated [BDNF](p) positively correlated with risk factors for metabolic syndrome and type 2 diabetes mellitus in middle age group of subjects. On the other hand it is well established that endurance training decreases the risk of diabetes and development of metabolic syndrome. In the present study we have examined the effect of 5 weeks of moderate intensity endurance training on the basal and the exercise induced changes in [BDNF](p) in humans. Thirteen young, healthy and physically active men (mean +/- S.E: age 22.7 +/- 0.5 yr, body height 180.2 +/- 1.7 cm, body weight 77.0 +/- 2.5 kg, V(O2max) 45.29 +/- 0.93 ml x kg-1 x min(-1)) performed a five week endurance cycling training program, composed mainly of moderate intensity bouts. Before training [BDNF]p at rest have amounted to 10.3 +/- 1.4 pg x ml(-1). No effect of a single maximal incremental cycling up to V(O2max) on its concentration was found (10.9 +/- 2.3 pg x ml(-1), P=0.74). The training resulted in a significant (P=0.01) increase in [BDNF]p at rest to 16.8 +/- 2.1 pg x ml(-1), as well as in significant (P=0.0002) exercise induced increase in the [BDNF](p) (10.9 +/- 2.3 pg x ml(-1) before training vs. 68.4 +/- 16.0 pg x ml(-1) after training). The training induced increase in resting [BDNF](p) was accompanied by a slight decrease in insulin resistance (P=0.25), calculated using the homeostatic model assessment version 2 (HOMA2-IR), amounting to 1.40 +/- 0.13 before and 1.15 +/- 0.13 after the training. Moreover, we have found that the basal [BDNF](p) in athletes (n=16) was significantly higher than in untrained subjects (n=13) (29.5 +/- 9.5 pg x ml(-1) vs. 10.3 +/- 1.4 pg x ml(-1), P=0.013). We have concluded that endurance training of moderate intensity increases both basal as well as the end-exercise [BDNF](p) in young healthy men. This adaptive response, contrariwise to the recent findings in patients with metabolic disorders, was accompanied by a slight decrease in insulin resistance.

Anxiolytic-like action of MTEP expressed in the conflict drinking Vogel test in rats is serotonin dependent.

The purpose of the present study was to investigate whether the anxiolytic-like action of a selective and brain penetrable group I metabotropic glutamate (mGlu5) receptor antagonist 3-[(2-methyl-1,3-tiazol-4-yl)ethynyl]-pyridine (MTEP) is dependent upon the serotonergic system. Experiments were performed on male Wistar rats. The Vogel conflict drinking test was used to detect anxiolytic-like activity. MTEP administered intraperitoneally at doses of 1, 3 and 6 mg/kg induced anxiolytic-like effect. The potential anxiolytic effect of MTEP (1 mg/kg) was inhibited by a nonselective 5-HT receptor antagonist metergoline (2 mg/kg i.p.) and 5-HT2A/2C receptor antagonist ritanserin (0.5 mg/kg i.p.), but not by a 5-HT1A receptor antagonist N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridynyl)cyclohexane-carboxamide (WAY 100635) (0.1 mg/kg i.p). The anxiolytic effect of MTEP (6 mg/kg) was attenuated by ritanserin (1 mg/kg i.p.). Moreover, MTEP-induced a dose-dependent release of serotonin in the frontal cortex. The obtained results suggest that the potential anxiolytic effect of the mGlu5 receptor antagonist MTEP is due to the increased serotonin release with subsequent activation of 5-HT2A/2C receptors, most probably located postsynaptically, but not by the 5-HT1A receptors.

The influence of group III metabotropic glutamate receptor stimulation by (1S,3R,4S)-1-aminocyclo-pentane-1,3,4-tricarboxylic acid on the parkinsonian-like akinesia and striatal proenkephalin and prodynorphin mRNA expression in rats.

Group III metabotropic glutamate receptors (mGluRs) are widely distributed in the basal ganglia, especially on the terminals of pathways which seem to be overactive in Parkinson's disease. The aim of the present study was to determine whether (1S,3R,4S)-1-aminocyclo-pentane-1,3,4-tricarboxylic acid (ACPT-1), an agonist of group III mGluRs, injected bilaterally into the globus pallidus (GP), striatum or substantia nigra pars reticulata (SNr), can attenuate the haloperidol-induced catalepsy in rats, and whether that effect was related to modulation of proenkephalin (PENK) or prodynorphin (PDYN) mRNA expression in the striatum. Administration of ACPT-1 (0.05-1.6 microg/0.5 microl/side) caused a dose-and-structure-dependent decrease in the haloperidol (0.5 mg/kg i.p. or 1.5 mg/kg s.c.)-induced catalepsy whose order was as follows: GP>striatum>SNr. ACPT-1, given alone to any of those structures, induced no catalepsy in rats. Haloperidol (3 x 1.5 mg/kg s.c.) significantly increased PENK mRNA expression in the striatum, while PDYN mRNA levels were not affected by that treatment. ACPT-1 (3 x 1.6 microg/0.5 microl/side) injected into the striatum significantly attenuated the haloperidol-increased PENK mRNA expression, whereas administration of that compound into the GP or SNr did not influence the haloperidol-increased striatal PENK mRNA levels. Our results demonstrate that stimulation of group III mGluRs in the striatum, GP or SNr exerts antiparkinsonian-like effects in rats. The anticataleptic effect of intrastriatally injected ACPT-1 seems to correlate with diminished striatal PENK mRNA expression. However, since the anticataleptic effect produced by intrapallidal and intranigral injection of ACPT-1 is not related to a simultaneous decrease in striatal PENK mRNA levels, it is likely that a decrease in enkephalin biosynthesis is not a necessary condition to obtain an antiparkinsonian effect.

Combined administration of PHCCC, a positive allosteric modulator of mGlu4 receptors and ACPT-I, mGlu III receptor agonist evokes antidepressant-like effects in rats.

Numerous pharmacological data indicate involvement of glutamate, the major excitatory neurotransmitter in the brain, in the pathophysiology of several neuropsychiatric disorders. It was shown in the preclinical studies that compounds which can reduce the excess of glutamate release (for example group III metabotropic receptors agonists) possess potential therapeutic properties. Thus we focused our interests on (-)-N-phenyl-7-(hydroxyimino) cyclopropa[b]chromen-1a-carboxamide (PHCCC), which is a positive allosteric modulator of mGlu4 receptor. We examined the potential antidepressant-like activity of PHCCC after injection into the brain ventricles alone, or together with (1S,3R,4S)-1-aminocyclo-pentane-1,3,4-tricarboxylic acid (ACPT-I), a nonselective group III mGlu receptor agonist, using the forced swimming test (FST) in rats. We found that ACPT-I induced a dose dependent antidepressant-like effect in FST, which was blocked by an antagonist of group III mGlu receptors (RS)-alpha-cyclopropyl-4-phosphonophenylglycine (CPPG). PHCCC injected intracerebroventricular was not effective, however when the compound was administered together with non-effective dose of ACPT-I, a profound antidepressant-like activity in FST was demonstrated. This effect was reversed by CPPG, group III mGlu receptors antagonist. Results of our studies indicate that a combined administration positive allosteric modulation of mGlu4 receptor and agonists of group III mGlu receptors may be a promising target in the future treatment of depressive disorder.

An influence of ligands of metabotropic glutamate receptor subtypes on parkinsonian-like symptoms and the striatopallidal pathway in rats.

Several data indicate that inhibition of glutamatergic transmission may be important to alleviate of parkinsonian symptoms. Therefore, the aim of the present paper is to review recent studies on the search for putative antiparkinsonian-like effects of mGluR ligands and their brain targets. In order to inhibit glutamatergic transmission, the group I mGluRs (mGluR1 and mGluR5) were blocked, and group II (mGluR2/3) or III (mGluR4/7/8) mGluRs were activated. Systemic or intrastriatal administration of group I mGluR antagonists (mGluR5 - MPEP, MTEP; mGluR1 - AIDA) was found to inhibit parkinsonian-like symptoms (catalepsy, muscle rigidity) in rats. MPEP administered systemically and mGluR1 antagonists (AIDA, CPCCOEt, LY367385) injected intrastriatally reversed also the haloperidol-increased proenkephalin (PENK) mRNA expression in the striatopallidal pathway. Similarly, ACPT-1, a group III mGluR agonist, administered into the striatum, globus pallidus or substantia nigra inhibited the catalepsy. Intrastriatal injection of this compound reduced the striatal PENK expression induced by haloperidol. In contrast, a group II mGluR agonist (2R,4R-APDC) administered intrastriatally reduced neither PENK expression nor the above-mentioned parkinsonian-like symptoms. Moreover, a mixed mGluR8 agonist/AMPA antagonist, (R,S)-3,4-DCPG, administered systemically evoked catalepsy and enhanced both the catalepsy and PENK expression induced by haloperidol. The results reviewed in this article seem to indicate that group I mGluR antagonists or some agonists of group III may possess antiparkinsonian properties, and point at the striatopallidal pathway as a potential target of therapeutic intervention.