Motor Coordination In Mice Research Articles

Involvement of monoaminergic targets in the antidepressant- and anxiolytic-like effects of the synthetic alkamide riparin IV: Elucidation of further mechanisms through pharmacological, neurochemistry and computational approaches

Despite recent advances, current antidepressants have considerable limitations: late onset of action and the high profile of refractoriness. Biomedical research with natural products has gained growing interest in the last years, and had provide useful candidates for new antidepressants. Riparins are a group of natural alkamides obtained from Aniba riparia, which had marked neuroactive effects, mainly as antidepressant and antinociceptive agents. We made modifications of the basic structure of riparins, originating a synthetic alkamide, also known as riparin IV (RipIV). RipIV demonstrated a superior analgesic effect than its congeners and a marked antidepressant-like effect. However, the basic mechanism for the central effects of RipIV remains unknown. Here, we aimed to investigate the participation of monoaminergic neurotransmission targets in the antidepressant-like effects of RipIV. To do this, we applied a combined approach of experimental (classical pharmacology and neurochemistry) and computer-aided techniques. Our results demonstrated that RipIV presented antidepressant- and anxiolytic-like effects without modifying locomotion and motor coordination of mice. Also, RipIV increased brain monoamines and their metabolite levels. At the higher dose (100 mg/kg), RipIV increased serotonin concentrations in all studied brain areas, while at the lower one (50 mg/kg), it increased mainly dopamine and noradrenaline levels. When tested with selective receptor antagonists, RipIV antidepressant effect showed dependence of the activation of multiple targets, including D1 and D2 dopamine receptors, 5-HT2A/2, 5-HT3 receptors and α2 adrenergic receptors. Molecular docking demonstrated favorable binding conformation and affinity of RipIV to monoamine oxidase B (MAO-B), serotonin transporter (SERT), α1 receptor, D2 receptor, dopamine transporter (DAT) and at some extent GABA-A receptor. RipIV also presented a computationally predicted favorable pharmacokinetic profile. Therefore, this study demonstrated the involvement of monoaminergic targets in the mechanism of RipIV antidepressant-like action, and provide evidence of it as a promising new antidepressant.

Effects of gastric inhibitory polypeptide (GIP) immunoneutralization on mouse motor coordination and memory

Gastric inhibitory polypeptide (GIP) is a regulatory peptide expressed in the mammalian upper small intestine, and both GIP and its receptor (GIPR) are expressed in the cortex and hippocampus regions of the brain as well. While learning and memory deficits have been observed in GIPR−/− mice, the effects of peripheral GIP immunoneutralization on motor-coordination, learning, and memory have not been examined. In the present study, adult GIPR−/− mice (KO) and age-matched wild-type C57BL/6 J mice (WT) received weekly vehicle PBS injections for 12 weeks, while a third group of wild-type mice were injected weekly for 12 weeks with 30 mg/kg body weight humanized GIP-mAb (AB) to assess the possibility of long-term effects of peripheral GIP antagonism on rodent memory and behavior. All mice groups then underwent a battery of tests that evaluated motor behavior, body coordination, and memory. Performance deficits in several memory studies after 12 weeks of treatment were demonstrated in KO, but not in AB or WT mice. Body coordination performance showed no significant differences among the 3 groups. A similar short-term study (3 injections over 9 days) was also conducted and the results were similar to those from the long-term study. Thus, short-term and long-term peripheral GIP antagonism by GIP-mAb did not appear to affect learning and memory in mice, consistent with the notion that the GIP-mAb does not cross the blood brain barrier. Furthermore, our studies indicate that GIP signaling in the brain appears to involve local neurocrine pathways.

BSCI-10. NEUROLOGICAL DYSFUNCTION CAUSED BY BRAIN TUMOR-GENERATED SOLID STRESS IS REVERSED BY LITHIUM

The compression of brain tissue by a tumor mass is believed to be a major cause of the clinical symptoms seen in patients. However, the biological consequences of these physical stresses on the brain tissue are unknown. Using clinical imaging and preclinical studies, we discovered that a subgroup of primary and metastatic brain tumors, classified as nodular based on the growth pattern, exert compressive solid stress on the surrounding brain tissue, leading to a decrease in local vascular perfusion, as well as neuronal death and impaired function. We demonstrated a causal link between solid stress and neurological dysfunction, by applying and removing cerebral compression, mimicking the mechanics of tumor growth and surgical resection respectively. Finally, we showed that treatment with lithium reduced solid stress-induced neuronal death and improved motor coordination in mice. Our results indicate that brain tumor-generated solid stress impairs neurological function in patients and show lithium as a potential therapeutic intervention to counter these effects.

N-Pyrazoloyl and N-thiopheneacetyl hydrazone of isatin exhibited potent anti-inflammatory and anti-nociceptive properties through suppression of NF-κB, MAPK and oxidative stress signaling in animal models of inflammation.

Hydrazide derivatives constitute an important class of compounds for new drug development as they are reported to possess good anti-inflammatory and analgesic activity. The present study was aimed to investigate the role of newly synthesized hydrazide derivatives N-pyrazoloyl hydrazone of isatin (PHI) and N-thiopheneacetyl hydrazone of isatin (THI) in acute and chronic inflammatory pain models induced by carrageenan and complete Freud's adjuvant (CFA). PHI and THI (0.1, 1 and 10mg/kg) pretreatments were provided intraperitoneally to male BALB/c mice prior to inflammatory inducers. Behavioral responses to inflammation and pain were evaluated by assessment of paw edema, mechanical allodynia, mechanical and thermal hyperalgesia. Cytokines production and NF-κB levels were evaluated by ELISA. Western blot analysis was performed for the detection of IκBα, p38, JNK and ERK. Hematoxylin and eosin (H&E) staining and radiographic analysis were performed to evaluate the effect of PHI and THI treatment on bone and soft tissues. Oxidative stress was determined by reduced glutathione, glutathione-S-transferase and catalase assays. Evans blue dye was used to monitor vascular protein leakage. PHI and THI dose dependently (0.1, 1 and 10mg/kg) reduced inflammation and pain in mice, however, the dose of 10mg/kg exhibited significant activity. The anti-inflammatory and analgesic effects were attributed to suppression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) productionlevels. PHI and THI significantly blocked CFA-induced activation of NF-κB and MAPK signaling pathways. Oxidative stress and plasma nitrite levels were reduced remarkably. The PHI and THI (10mg/kg) treatment did not exhibit any apparent toxicity on the liver, kidney, muscles strength, and motor co-ordination in mice. Both PHI and THI possess significant anti-inflammatory and analgesic activity via inhibition of inflammatory mediators.

Diuretic activity and neuropharmacological effects of an ethanol extract from Senna septemtrionalis (Viv.) H.S. Irwin & Barneby (Fabaceae)

Ethnopharmacological relevance Senna septemtrionalis (Viv.) H.S. Irwin & Barneby (Fabaceae) is a shrub empirically used as diuretic, and for the treatment of neurological disorders. These pharmacological effects have not been previously evaluated. Aim of the studyTo evaluate the diuretic and CNS effects of a standardized ethanol extract of Senna septemtrionalis aerial parts (SSE). Materials and methodsGas chromatography mass spectrometry was used to perform a chemical analysis with SSE. In all tests, SSE was evaluated from 10 to 100 mg/kg p.o.The diuretic activity of SSE was assessed in mice individually placed in metabolic cages. After 6 h, the urine volume and the electrolyte excretion (Na and K) were measured. The role of prostaglandins and nitric oxide was assessed administrating mice with indomethacin and N(ω)-nitro-L-arginine methyl ester (L-NAME), prior the administration of 100 mg/kg SSE. The sedative effects of SSE were analyzed with the pentobarbital-induced sleeping time test. The effects of SSE on motor coordination in mice were evaluated with the rotarod test. The antidepressant-like activity of SSE was analyzed with the forced swimming test (FST) and the tail suspension test (TST). The role of 5-HT2 receptor, α1-and α2-adrenoceptors, or muscarinic receptors was assessed administrating mice with cyproheptadine, prazosin, yohimbine, and atropine, respectively, prior the administration of 100 mg/kg SSE in the FST. The anxiolytic-like activity of SSE (10–100 mg/kg p.o.) was assessed using the light-dark test (LDB), the elevated plus maze test (EPM), the cylinder exploratory test, and the open field test (OFT). The anticonvulsant effect of SSE (1–100 mg/kg) was evaluated in mice administered with different convulsant agents: strychnine, pentylenetetrazol (PTZ), isoniazid (INH) or yohimbine. ResultsThe main compound found in SSE was D-pinitol (42.2%). SSE (100 mg/kg) increased the urinary volume (2.67-fold), as well as the excretion of Na (5.60-fold) and K (7.2-fold). The co-administration of SSE with L-NAME or indomethacin reverted the diuretic activity shown by SSE alone. SSE lacked sedative effects and did not affect motor coordination in mice. SSE (100 mg/kg) showed higher and similar antidepressant-like effect, compared to 20 mg/kg fluoxetine, in the FST and TST, respectively. The co-administration of SSE with yohimbine reverted the antidepressant-like activity shown by SSE alone. SSE (100 mg/kg) showed anxiolytic-like activity in the four models of anxiety, with similar activity with 1.5 mg/kg clonazepam. The seizure-protective effect of SSE was ED50 = 73.9 ± 8.4 mg/kg (INH) and 40.4 ± 5.2 mg/kg (yohimbine). ConclusionThe diuretic effects of SSE involve the possible contribution of prostaglandins and nitric oxide. SSE showed moderate anxiolytic and anticonvulsant effects, whereas the participation of α2-adrenoceptors is probably associated in the antidepressant-like effects of SSE.

IN VIVO STUDY OF THE ACTION MECHANISM OF THE RAPITALAM PHARMACEUTICAL SUBSTANCE

The aimis to study the action mechanisms of the Rapitalam pharmaceutical substance using Parkinsonian syndrome models.Materials and methods.Various effects of a new pharmacological substance, N-chlorophenylmethyl-dihydro-methoxy-methylphenyl-oxopyridazine carboxamide (Rapitalam), were studied in male laboratory mice and rats. During the experiment, the various models of the Parkinsonian syndrome were reproduced: the simulation of the Parkinsonian syndrome by administering 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP) neurotoxin, the simulation of haloperidol-induced catalepsy, the simulation of apomorphine-induced stereotypy and the simulation of oxotremorine-induced tremor followed by tests. The following tests were carried out in order to determine the Rapitalam efficacy with regard to symptoms manifested after the MPTP administration in animals: the open field test, the rotarod performance test, as well as the evaluation of the grip strength and the degree of rigidity using the stride length. When simulating the haloperidol-induced catalepsy, a horizontal bar test was performed. After the administration of apomorphine, the severity of stereotypy was assessed in scores. A simulation of oxotremorine-induced tremor in rats was used to study the cholinergic link. After the administration of oxotremorine, the severity of tremor was assessed against the background of administration of the test compounds.Results.During the analysis of the data obtained in the open field and rotarod tests as well as the stride length and the grip force when simulating the Parkinsonian syndrome by introducing MPTP, no intergroup statistical differences were found. Thus, the tested Rapitalam substance in doses of 2 mg/kg, 6 mg/kg and 20 mg/kg and the Levodopa reference drug at a dose of 60 mg/kg had no effect on the indices of motor activity and motor coordination in mice when administered orally for 10 days. Rapitalam in doses of 1 mg/kg, 3 mg/kg and 10 mg/kg as well as the Levodopa reference drug at a dose of 50 mg/kg, did not affect the severity of haloperidol-induced catalepsy and apomorphine-induced stereotypy in rats. Under the administration of oxotremorine to laboratory animals, a statistically significant decrease in the severity of tremor was observed during the Rapitalam administration in doses of 3 mg/kg and 10 mg/kg.Conclusion.Rapitalam is established to have no effect on motor impairment due to dopaminergic mechanisms. The tested substance is characterized by a pronounced cholinoblocking effect at doses of 3 mg/kg and 10 mg/kg.Conflict of interest: the author declares no conflict of interest.

Anticonvulsant Activity of Pterostilbene in Zebrafish and Mouse Acute Seizure Tests

Pterostilbene (PTE), a natural dimethylated analog of resveratrol, possesses numerous health-beneficial properties. The ability of PTE to cross the blood–brain barrier raised the possibility that this compound may modulate central nervous system functions, including seizure activity. The aim of our study was to investigate the activity of PTE in the larval zebrafish pentylenetetrazole (PTZ) seizure assay and three acute seizure tests in mice, i.e., in the maximal electroshock seizure threshold (MEST), 6 Hz-induced psychomotor seizure threshold and intravenous (iv) PTZ tests. Additionally, potential antidepressant activity of PTE was estimated in the forced swim test in mice. The chimney test was used to determine the influence of PTE on motor coordination in mice, while its influence on neuromuscular strength was assessed in the grip strength test in mice. Locomotor activity was determined to verify the results from the forced swim test. PTE revealed an evident anticonvulsant effect both in zebrafish larvae (10 µM; 2 h-incubation) and mice (at doses of 100 and 200 mg/kg, intraperitoneally) but it did not exhibit antidepressant potential in the forced swim test. Furthermore, it did not cause any statistically significant changes in motor coordination, neuromuscular strength and locomotor activity in mice. In conclusion, our present findings demonstrate for the first time the anticonvulsant potential of PTE. The aforementioned results suggest that it might be employed in epilepsy treatment, however, further precise studies are required to verify its activity in other experimental seizure and epilepsy models and its precise mechanism of action should be determined.

Mechanisms by which fibroblast growth factor 20 improves motor performance in a mouse model of Parkinson's disease.

Genome-wide studies have reported that Parkinson's disease is associated with abnormal expression of various growth factors. In this study, male C57BL/6 mice aged 10 weeks were used to establish Parkinson's disease models using an intraperitoneal injection of 60 mg/kg 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. 28 days later, 10 or 100 ng fibroblast growth factor 20 was injected intracerebroventricularly. The electrophysiological changes in the mouse hippocampus were recorded using a full-cell patch clamp. Expression of Kv4.2 in the substantia nigra was analyzed using a western blot assay. Serum malondialdehyde levels were analyzed by enzyme-linked immunosorbent assay. The motor coordination of mice was evaluated using the rotarod test. The results showed that fibroblast growth factor 20 decreased A-type potassium current in neurons of the substantia nigra, increased long-term potentiation amplitude in the hippocampus, and downregulated Kv4.2 expression. A high dose of fibroblast growth factor 20 reduced serum malondialdehyde levels and enhanced the motor coordination of mice. These findings confirm that fibroblast growth factor 20 has a therapeutic effect on the toxicity induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, and its mechanism of action is associated with the inhibition of A-type K+ currents and Kv4.2 expression. All animal procedures were approved by the Animal Care and Use Committee of Qilu Hospital of Shandong University, China in 2017 (approval No. KYLL-2017-0012).

Antinociceptive properties of 25-methoxy hispidol A, a triterpinoid isolated from Poncirus trifoliata (Rutaceae) through inhibition of NF-κB signalling in mice.

The 25-methoxy hispidol A (25-MHA) is a triterpenoid, isolated from the immature fruit of Poncirus trifoliata (Rutaceae). The pretreatment with 25-MHA markedly (p<0.001) attenuated the formalin-induced biphasic responses as well as acetic acid-induced writhing responses. The intraperitoneal administration of 25-MHA significantly attenuated the mechanical hyperalgesia (p<0.001) and allodynia (p<0.05). Similarly, 25-MHA also significantly attenuated (p<0.001) complete Freund's adjuvant (CFA)-induced paw edema in mice. The 25-MHA treatment significantly attenuated the production of nuclear kappa B (NF-κB) (p65 nuclear subunit). The cytokines are the important mediators of inflammation and pain; however, treatment with 25-MHA exhibited significant inhibition (p<0.001) on the mRNA expression levels of various inflammatory mediators. The 25-MHA administration also significantly enhanced antioxidant enzymes (p < 0.001) and inhibited the oxidative stress markers. The current study indicates that 25-MHA significantly (p<0.001) inhibited the nitric oxide (NO) in mice plasma. Similarly, the haematoxylin and eosin (H&E) staining shows that 25-MHA administration significantly inhibited the inflammatory process in the mice paw tissue compared with the CFA-treated group. The 25-MHA treatment did not exhibited any toxicity on the liver, kidney, muscles strength, and motor co-ordination in mice. The 25-MHA was coadministered with the various drugs such as tramadol, piroxicam, and gabapentin to observe the synergistic effect.

Effect of Nelumbo nucifera fruit on scopolamine induced memory deficits and motor coordination.

From prehistoric time till today herbal medications are supposed to have neuroprotective effects both by inhibiting acetyl cholinesterase enzyme or antioxidant ability and are also affordable. Thus extensive studies are necessary to investigate the pharmacological effects of herbal plants. The goal of the present study was to ascertain the outcome of Nelumbo nucifera fruit (NNF) on scopolamine induced amnestic rats along with motor coordination in mice in order to explore its pharmacological use in disorders like Alzheimer's disease (AD). The effect of NNF on learning and memory was assessed by Morris water maze test using 35 Wister rats weighing 200-230g evenly divided in to five groups. While motor coordination was assessed using Rot rod test, 35 male locally bred albino mice weighing 20-25g were equally divided in to five groups. Group I was kept as control (10ml/kg gum tragacanth). Group II, III and IV were labeled as treated groups (NNF 50, 100 and 200mg/kg). Group V served as reference group (piracetam 200mg/kg). All drugs were given by oral route as a single dose for 15days in both experiments to rats and mice, however scopolamine (1mg/kg IP) was used in Morris water maze test 40min after the administration of drugs to rats for the induction of amnesia. In Morris water maze test, N. nucifera fruit caused highly significant and significant decrease in escape latency in the amnestic rats at 200 and 100mg/kg as compared to control. In Rota rod test, N. nucifera fruit did not exhibit any notable changes in the riding time at any dose as compared to control. N. nucifera fruit have demonstrated ameliorating effects on memory without affecting muscle coordination. Hence NNF seems to have great potential for therapeutic application in memory disorders, such as AD which may be due to its ability to enhance cholinergic neurotransmission and exerting antioxidant effect and thus encourage more preclinical and clinical trials in this field.

Time-shifted co-administration of sub-analgesic doses of ambroxol and pregabalin attenuates oxaliplatin-induced cold allodynia in mice

BackgroundOxaliplatin-induced cold allodynia is a frequent complication appearing in patients treated with this anti-tumor drug. Since, there are no clear algorithms to overcome this painful condition effectively, it is important to establish novel strategies for its treatment. AimIn this study, the ability of pregabalin and ambroxol, used as single drugs or in combinations administered in a time-shifted manner to attenuate cold allodynia was assessed in the mouse cold plate test. The hot plate test was additionally used to assess antinociceptive properties of ambroxol in the acute, thermally-induced pain model. Locomotor activity and motor coordination of mice were also evaluated. In silico studies were undertaken to predict potential binding of ambroxol to sodium channel (Nav) subtypes whose overexpression is implicated in the development of oxaliplatin-induced neuropathic pain. Key findingsA hyperadditive antiallodynic effect of combined sub-analgesic ambroxol and pregabalin was demonstrated in oxaliplatin-treated mice. This effect was particularly strong when these drugs were given 4 h apart. Both drugs used in combination reduced animals’ locomotor activity, but they did not impair motor coordination in the rotarod test. Ambroxol did not show antinociceptive properties in the hot plate test. The molecular docking studies predicted that in mice ambroxol might bind to Nav1.6 and Nav1.9 rather than Nav1.7 and Nav1.8. SignificanceTime-shifted co-administration of sub-analgesic doses of ambroxol and pregabalin effectively attenuates oxaliplatin-induced cold allodynia. Molecular docking model predicts preferential binding of ambroxol to mouse Nav1.6, Nav1.9 channels. This mechanism, if confirmed in vitro, might explain pharmacological activities observed in vivo.

Mercurius solubilis attenuates scopolamine-induced memory deficits and enhances the motor coordination in mice

ABSTRACTAim: The present study was designed to investigate the effect of mercurius solubilis (merc sol) on scopolamine induced memory deficits and motor coordination in mice.Materials and methods: Three different formulations of merc sol (30X, 200M, 1M) were screened for their in vitro antioxidant potential through DPPH (2, 2-diphenyl-1-picrylhydrazyl) and nitric oxide scavenging activity using response surface methodology. Memory impairment was induced by the administration of scopolamine (1mg/kg i.p.) for 3 days to mice and assessment of memory acquisition and retention was done using Morris water maze test, passive avoidance test, elevated plus maze test, light and dark box test, motor coordination was evaluated using rotarod test and inclined plan test. The involvement of ion channels and nitric oxide pathway in the observed effect of merc sol was elucidated by administration of veratrine (0.125 μg/kg, i.p.), A23187 (20 μg/kg, i.p.), L- arginine (40 mg/kg, i.p.), aminoguanidine (50 mg/kg, i.p.) 30 min prior to merc sol. Acute toxicity studies were performed in accordance with the OECD (Organisation for Economic Co-operation and Development) guidelines.Results: In vitro studies have revealed merc sol 30 X to have maximum free radical and nitric oxide scavenging activity. Administration of merc sol 30 X to mice significantly reduced scopolamine induced memory deficits and motor incoordination in all the performance tasks. The calcium ionophore, A23187 significantly altered the effect of merc sol in mice. No major signs of toxicity were observed.Conclusion: Merc sol has antiamnesic effect in scopolamine induced deficits and motor coordination in mice.

Protective effect of alpha-linolenic acid on gentamicin-induced ototoxicity in mice

Alpha-linolenic acid is one of the fatty acids known as omega 3. Previous studies have shown the antioxidant and anti-inflammatory effects of alpha-linolenic acid, which prevented cell damage by inhibiting apoptotic pathway. Also, it is known that gentamicin activates apoptotic mediators and causes necrosis in the kidney. Due to this reason, we planned a study to evaluate the protective effects of alpha-linolenic acid on gentamicin induced ototoxicity by evaluating inflammation and apoptotic mediators. For this purpose, 100 mg/kg gentamicin (i.p; intraperitoneally) and 200 mg/kg alpha-linolenic acid (gavage) are administered to mice for 9 days. On 9th and 10th days, rotarod performance was assessed to test the effect of gentamicin and alpha-linolenic acid treatment on the motor coordination of mice. Gentamicin treatment decreased fall latency of mice and gentamicin treatment together with alpha-linolenic acid increased fall latency of mice. Gentamicin treatment also increased expression of phospholipase A2(plA2), cyclooxygenase-2(COX-2) and inducible nitric oxide syntheses (iNOS). Furthermore, it increased Bax and caspase-3, which are proapoptotic proteins and decreased bcl-2 that is an antiapoptotic protein. Gentamicin treatment together alpha-linolenic acid recovered the change of expression of these enzymes. In conclusion, this study showed that alpha-linolenic acid will be useful to prevent gentamicin-induced ototoxicity by inhibiting apoptosis and inflammation.

MTCL1 plays an essential role in maintaining Purkinje neuron axon initial segment.

The axon initial segment (AIS) is a specialized domain essential for neuronal function, the formation of which begins with localization of an ankyrin-G (AnkG) scaffold. However, the mechanism directing and maintaining AnkG localization is largely unknown. In this study, we demonstrate that invivo knockdown of microtubule cross-linking factor 1 (MTCL1) in cerebellar Purkinje cells causes loss of axonal polarity coupled with AnkG mislocalization. MTCL1 lacking MT-stabilizing activity failed to restore these defects, and stable MT bundles spanning the AIS were disorganized in knockdown cells. Interestingly, during early postnatal development, colocalization of MTCL1 with these stable MT bundles was observed prominently in the axon hillock and proximal axon. These results indicate that MTCL1-mediated formation of stable MT bundles is crucial for maintenance of AnkG localization. We also demonstrate that Mtcl1 gene disruption results in abnormal motor coordination with Purkinje cell degeneration, and provide evidence suggesting possible involvement of MTCL1 dysfunction in the pathogenesis of spinocerebellar ataxia.

Effect of methanol extract of Trigonella foenum-graecum L. seeds on anxiety, sedation and motor coordination.

Currently available anxiolytics cause numerous adverse effects and show craving and tolerance during long term treatment. Currently traditional medicines have been re-evaluated widely through work on various plant species. Numerous plants in traditional system show pharmacological activity with unlimited prospective for therapeutic use. Hence we planned to evaluate the effect of methanol extract of T. foenum-graecum L. seeds on anxiety, sedation and motor coordination in mice at different doses following 15days of oral feeding. Effect on anxiety was assessed by Hole board test and Light and Dark transition models.Phenobarbitone induced sleeping time and Rota rod test were performed to assess effect on sedation and motor coordination. In Hole board test, T. foenum-graecum L. seeds decreased the number of head dips in mice at all the three doses. In Light and Dark transition model, T. foenum-graecum L. seeds increased the period spent in the light box and the number of moves among the two compartments at 100 and 200mg/kg as compared to control animals. In phenobarbitone induced sleeping time, T. foenum-graecum L. seeds did not reveal any sedative effect. In Rota rod test, extract exhibited significant skeletal muscle relaxant effect at 200mg/kg (at 90min) as compared to the control animals. Results of our study shows significant antianxiety effects of T. foenum-graecum L. seeds and may also recommend improved adverse effect profile as compared to diazepam.

MiR-17-92 facilitates neuronal differentiation of transplanted neural stem/precursor cells under neuroinflammatory conditions.

BackgroundNeural stem/precursor cells (NSCs) are of particular interest because of their potential application in cell therapy for brain damage. However, most brain injury cases are followed with neuroinflammatory stress, which affects the lineage selection of grafted NSCs by promoting astrocytogenesis, thus hampering the potential for neural replacement. The present study investigated the role of miR-17-92 in protecting against detrimental effects of neuroinflammation on NSC differentiation in cell therapy.MethodsNSCs were treated with conditioned medium from lesioned astrocytes with/without neutralizing antibodies of leukemia inhibitory factor (LIF) or/and ciliary neurotrophic factor (CNTF), respectively. Afterward, the levels of p-STAT3 and p-JAK2 were determined by western blotting while expression of glial fibrillary acidic protein (GFAP) and β-tubulin III was assessed by immunostaining. The activation of JAK-STAT pathway and cell differentiation were also evaluated after we overexpressed miR-17-92 in NSCs under different neuroinflammatory conditions. After the transplantation of miR-17-92-overexpressing NSCs into injured mouse cortex, PH3, nestin, GFAP, and NeuN were analyzed by immunostaining. In addition, motor coordination of mice was evaluated by rotarod test.ResultsConditioned medium from lesioned astrocytes activated JAK-STAT pathway and facilitated astrocytic differentiation in NSCs while neutralizing antibodies of LIF and CNTF remarkably attenuated such effects. miR-17-92 cluster repressed the expression of multiple proteins including GP130, CNTFR, JAK2, and STAT3 in JAK-STAT pathway. Overexpression of miR-17-92 in NSCs systematically blocked the activation of JAK-STAT pathway mediated by LIF and CNTF, which facilitated neuronal differentiation in vitro. Furthermore, miR-17-92 increased neuronal generation of grafted NSCs and reduced astrogliosis, which resulted in the improvement of motor coordination of brain-injured mice.ConclusionsOur results suggest that miR-17-92 promotes neuronal differentiation of grafted NSCs under neuroinflammatory condition via inhibition of multiple proteins in JAK-STAT pathway.Electronic supplementary materialThe online version of this article (doi:10.1186/s12974-016-0685-5) contains supplementary material, which is available to authorized users.

PT683. Effects of acute administration of moderate and high caffeine doses on the spatial memory and motor coordination in mice.

PT683. Effects of acute administration of moderate and high caffeine doses on the spatial memory and motor coordination in mice.

Gene Transfer of Brain-derived Neurotrophic Factor (BDNF) Prevents Neurodegeneration Triggered by FXN Deficiency

Friedreich's ataxia is a predominantly neurodegenerative disease caused by recessive mutations that produce a deficiency of frataxin (FXN). Here, we have used a herpesviral amplicon vector carrying a gene encoding for brain-derived neurotrophic factor (BDNF) to drive its overexpression in neuronal cells and test for its effect on FXN-deficient neurons both in culture and in the mouse cerebellum in vivo. Gene transfer of BDNF to primary cultures of mouse neurons prevents the apoptosis which is triggered by the knockdown of FXN gene expression. This neuroprotective effect of BDNF is also observed in vivo in a viral vector-based knockdown mouse cerebellar model. The injection of a lentiviral vector carrying a minigene encoding for a FXN-specific short hairpin ribonucleic acid (shRNA) into the mouse cerebellar cortex triggers a FXN deficit which is accompanied by significant apoptosis of granule neurons as well as loss of calbindin in Purkinje cells. These pathological changes are accompanied by a loss of motor coordination of mice as assayed by the rota-rod test. Coinjection of a herpesviral vector encoding for BDNF efficiently prevents both the development of cerebellar neuropathology and the ataxic phenotype. These data demonstrate the potential therapeutic usefulness of neurotrophins like BDNF to protect FXN-deficient neurons from degeneration.

HBK-7 — A new xanthone derivative and a 5-HT1A receptor antagonist with antidepressant-like properties

Xanthone derivatives possess many biological properties, including neuroprotective, antioxidant or antidepressant-like. In this study we aimed to investigate antidepressant- and anxiolytic-like properties of a new xanthone derivative – 6-methoxy-4-[4-(2-methoxyphenyl)piperazin-1-yl]-9H-xanthen-9-one (HBK-7), as well as its possible mechanism of action, and the influence on cognitive and motor function. HBK-7 in our earlier studies showed high affinity for serotonergic 5-HT1A receptor. We determined the affinity of HBK-7 for CNS receptors and transporters using radioligand assays and examined its intrinsic activity towards 5-HT1A receptor. We evaluated antidepressant- and anxiolytic-like activity of HBK-7 in the mouse forced swim test, and four-plate test, respectively. We examined the influence on locomotor activity in mice to determine if the effect observed in the forced swim test was specific. We used step-through passive avoidance and rotarod tests to evaluate the influence of HBK-7 on cognitive and motor function, respectively. HBK-7 showed moderate affinity for dopaminergic D2 receptor and very low for serotonergic 5-HT2A, adrenergic α2 receptors, as well as serotonin transporter. Functional studies revealed that HBK-7 was a 5-HT1A receptor antagonist. HBK-7 (10mg/kg) decreased immobility time in the forced swim test. Combined treatment with sub-effective doses of HBK-7 and fluoxetine reduced immobility of mice in the forced swim test. Pretreatment with p-chlorophenylalanine and WAY-100,635 antagonized the antidepressant-like effect of HBK-7. Neither of the treatments influenced locomotor activity of mice. HBK-7 at antidepressant-like dose did not impair memory or motor coordination in mice. We demonstrated that HBK-7 was a 5-HT1A receptor antagonist with potent, comparable to mianserin, antidepressant-like activity. HBK-7 mediated its effect through serotonergic system and its antidepressant-like action required the activation of 5-HT1A receptors. At active dose it did not influence cognitive and motor function. Since 5-HT1A receptor antagonists may accelerate the occurrence of antidepressant effect, our findings highlight their potential as future antidepressants.

Influence of caffeine on the protective activity of gabapentin and topiramate in a mouse model of generalized tonic-clonic seizures.

Caffeine may interact with classical antiepileptic drugs (AEDs), reducing their anticonvulsant effects in basic seizure models. The aim of the present study was to ascertain whether intraperitoneal caffeine (acute or chronic for 15 days) could attenuate the anticonvulsant effect of some newer AEDs: gabapentin (GBP) and topiramate (TPM) against electroconvulsions in mice. Maximal electroshock (MES)-induced mouse seizure model was used for the estimation of the anticonvulsant activity of TPM whilst the protective activity of GBP was evaluated in the threshold test for maximal (tonic) convulsions. Adverse effects were evaluated by measurement of long-term memory (the step-through passive avoidance task) and motor coordination (chimney test). Plasma AED concentrations were also measured to determinate any pharmacokinetic contribution to the observed effects. Caffeine (both acute and chronic at 23.1 and 46.2mg/kg) significantly reduced the protective effects of TPM against MES. As regards GBP, caffeine (acutely at 46.2mg/kg and chronically at 23.1 or 46.2mg/kg) significantly diminished the GBP-induced increases in the electroconvulsive threshold. In addition, caffeine did not affect the free plasma concentrations of TPM or GBP. Acute and chronic caffeine (23.1 and 46.2mg/kg) enhanced the impairment of motor coordination in mice pretreated with GBP whilst an opposite effect was observed in TPM injected mice and pretreated with chronic caffeine at 46.2mg/kg. The results indicate that newer AEDs, GBP or TPM behave in the exactly same way as classical antiepileptics in mice challenged with caffeine. This hazardous effect of caffeine is not subject to tolerance.