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Sample records for 5-hydroxytryptamine modulates migration

  1. Modulation of the hypoxic sensory response of the carotid body by 5-hydroxytryptamine: role of the 5-HT2 receptor.

    PubMed

    Jacono, F J; Peng, Y-J; Kumar, G K; Prabhakar, N R

    2005-02-15

    Previous studies have shown that glomus cells of the carotid body express 5-hydroxytryptamine (5-HT). The aim of this study was to elucidate the role of 5-HT on the hypoxic sensory response (HSR) of the carotid body. Sensory activity was recorded from multi-fiber (n=16) and single-fiber (n=8) preparations of ex vivo carotid bodies harvested from anesthetized, adult rats. 5-HT (3 microM) had no significant effect on the magnitude or on the onset of the HSR. However, 5-HT consistently prolonged the time necessary for the sensory activity to return to baseline following the termination of the hypoxic challenge. Ketanserin (40 microM), a 5-HT2 receptor antagonist completely prevented 5-HT-induced prolongation of the HSR, whereas had no effect on the control HSR (onset, magnitude, and time for decay without 5-HT). Carotid bodies expressed 5-HT, but hypoxia did not facilitate 5-HT release. These observations suggest that 5-HT is not critical for the HSR of the rat carotid body, but it modulates the dynamics of the HSR via its action on 5-HT2 receptors.

  2. 5-Hydroxytryptamine modulates cytokine and chemokine production in LPS-primed human monocytes via stimulation of different 5-HTR subtypes.

    PubMed

    Dürk, Thorsten; Panther, Elisabeth; Müller, Tobias; Sorichter, Stephan; Ferrari, Davide; Pizzirani, Cinzia; Di Virgilio, Francesco; Myrtek, Daniel; Norgauer, Johannes; Idzko, Marco

    2005-05-01

    The neurotransmitter 5-hydroxytryptamine (5-HT), commonly known as serotonin, is released at peripheral sites from activated enterochromaffin cells, mast cells and platelets. In this study we analyzed the biological activity and intracellular signaling of 5-HT in human monocytes. By reverse transcription (RT) and PCR, messenger RNA (mRNA) expression of 5-HT receptor 1E (5-HTR(1E)), 5-HTR(2A), 5-HTR(3), 5-HTR(4) and 5-HTR(7) could be revealed. Functional studies showed that 5-HT modulates the release of IL-1beta, IL-6, IL-8/CXCL8, IL-12p40 and tumor necrosis factor-alpha (TNF-alpha), while it has no effect on the production of IL-18 and IFN-gamma in LPS-stimulated human blood monocytes. Moreover, RT and PCR revealed that 5-HT modulated mRNA levels of IL-6 and IL-8/CXCL8, but did not influence mRNA levels of IL-1beta and TNF-alpha. Pharmacological studies with isotype-selective receptor agonists allowed us to show that 5-HTR(3) subtype up-regulates the LPS-induced production of IL-1beta, IL-6 and IL-8/CXCL8, while it was not involved in TNF-alpha and IL-12p40 secretion. Furthermore, activation of the G(s)-coupled 5-HTR(4) and 5-HTR(7) subtypes increased intracellular cyclic AMP (cAMP) and secretion of IL-1beta, IL-6, IL-12p40 and IL-8/CXCL8, while, on the contrary, it inhibited LPS-induced TNF-alpha release. Interestingly, 5-HTR(1) and 5-HTR(2) agonists did not modulate the LPS-induced cytokine production in human monocytes. Our results point to a new role for 5-HT in inflammation by modulating cytokine production in monocytes via activation of 5-HTR(3), 5-HTR(4) and 5-HTR(7) subtypes.

  3. Neuropharmacology of 5-hydroxytryptamine

    PubMed Central

    Richard Green, A

    2006-01-01

    This review outlines the history of our knowledge of the neuropharmacology of 5-hydroxytryptamine (5-HT; serotonin), focusing primarily on the work of U.K. scientists. The existence of a vasoconstrictive substance in the blood has been known for over 135 years. The substance was named serotonin and finally identified as 5-HT in 1949. The presence of 5-HT in the brain was reported by Gaddum in 1954 and it was Gaddum who also demonstrated that the action of 5-HT (in the gut) was antagonised by the potent hallucinogen lysergic acid diethylamide. This provoked the notion that 5-HT played a pivotal role in the control of mood and subsequent investigations have generally confirmed this hypothesis. Over the last 50 years a good understanding has been gained of the mechanisms involved in control of the storage, synthesis and degradation of 5-HT in the brain. Knowledge has also been gained on control of the functional activity of this monoamine, often by the use of behavioural models. A considerable literature also now exists on the mechanisms by which many of the drugs used to treat psychiatric illness alter the functional activity of 5-HT, particularly the drugs used to treat depression. Over the last 20 years the number of identified 5-HT receptor subtypes has increased from 2 to 14, or possibly more. A major challenge now is to utilise this knowledge to develop receptor-specific drugs and use the information gained to better treat central nervous system disorders. PMID:16402098

  4. Chemocentric informatics approach to drug discovery: identification and experimental validation of selective estrogen receptor modulators as ligands of 5-hydroxytryptamine-6 receptors and as potential cognition enhancers.

    PubMed

    Hajjo, Rima; Setola, Vincent; Roth, Bryan L; Tropsha, Alexander

    2012-06-28

    We have devised a chemocentric informatics methodology for drug discovery integrating independent approaches to mining biomolecular databases. As a proof of concept, we have searched for novel putative cognition enhancers. First, we generated Quantitative Structure-Activity Relationship (QSAR) models of compounds binding to 5-hydroxytryptamine-6 receptor (5-HT(6)R), a known target for cognition enhancers, and employed these models for virtual screening to identify putative 5-HT(6)R actives. Second, we queried chemogenomics data from the Connectivity Map ( http://www.broad.mit.edu/cmap/ ) with the gene expression profile signatures of Alzheimer's disease patients to identify compounds putatively linked to the disease. Thirteen common hits were tested in 5-HT(6)R radioligand binding assays and ten were confirmed as actives. Four of them were known selective estrogen receptor modulators that were never reported as 5-HT(6)R ligands. Furthermore, nine of the confirmed actives were reported elsewhere to have memory-enhancing effects. The approaches discussed herein can be used broadly to identify novel drug-target-disease associations.

  5. 5-Hydroxytryptamine 1A receptors in the dorsomedial hypothalamus connected to dorsal raphe nucleus inputs modulate defensive behaviours and mediate innate fear-induced antinociception.

    PubMed

    Biagioni, Audrey Franceschi; de Oliveira, Rithiele Cristina; de Oliveira, Ricardo; da Silva, Juliana Almeida; dos Anjos-Garcia, Tayllon; Roncon, Camila Marroni; Corrado, Alexandre Pinto; Zangrossi, Hélio; Coimbra, Norberto Cysne

    2016-03-01

    The dorsal raphe nucleus (DRN) is an important brainstem source of 5-hydroxytryptamine (5-HT), and 5-HT plays a key role in the regulation of panic attacks. The aim of the present study was to determine whether 5-HT1A receptor-containing neurons in the medial hypothalamus (MH) receive neural projections from DRN and to then determine the role of this neural substrate in defensive responses. The neurotracer biotinylated dextran amine (BDA) was iontophoretically microinjected into the DRN, and immunohistochemical approaches were then used to identify 5HT1A receptor-labelled neurons in the MH. Moreover, the effects of pre-treatment of the dorsomedial hypothalamus (DMH) with 8-OH-DPAT and WAY-100635, a 5-HT1A receptor agonist and antagonist, respectively, followed by local microinjections of bicuculline, a GABAA receptor antagonist, were investigated. We found that there are many projections from the DRN to the perifornical lateral hypothalamus (PeFLH) but also to DMH and ventromedial (VMH) nuclei, reaching 5HT1A receptor-labelled perikarya. DMH GABAA receptor blockade elicited defensive responses that were followed by antinociception. DMH treatment with 8-OH-DPAT decreased escape responses, which strongly suggests that the 5-HT1A receptor modulates the defensive responses. However, DMH treatment with WAY-100635 failed to alter bicuculline-induced defensive responses, suggesting that 5-HT exerts a phasic influence on 5-HT1A DMH neurons. The activation of the inhibitory 5-HT1A receptor had no effect on antinociception. However, blockade of the 5-HT1A receptor decreased fear-induced antinociception. The present data suggest that the ascending pathways from the DRN to the DMH modulate panic-like defensive behaviours and mediate antinociceptive phenomenon by recruiting 5-HT1A receptor in the MH.

  6. 5-hydroxytryptamine-mediated neurotransmission modulates spontaneous and vagal-evoked glutamate release in the nucleus of the solitary tract effect of uptake blockade.

    PubMed

    Hosford, Patrick S; Mifflin, Steve W; Ramage, Andrew G

    2014-05-01

    The effect of blockade of either 5-hydroxytryptamine (5-HT)/serotonin transporter (SERT) with citalopram or the organic cation transporter 3 (OCT3)/plasma membrane monoamine transporter (PMAT) with decynium-22 (D-22) on spontaneous and evoked release of 5-HT in the nucleus tractus solitarius (NTS) was investigated in rat brainstem slices treated with gabazine. 5-HT release was measured indirectly by changes in the frequency and amplitude of glutamatergic miniature excitatory postsynaptic currents (mEPSCs) [in the presence of tetrodotoxin (TTX)] and evoked EPSCs. Blockade of 5-HT3 receptors with granisetron reduced, whereas the 5-HT3 agonist phenylbiguanide increased, the frequency of mEPSCs. 5-HT decreased mEPSC frequency at low concentrations and increased frequency at high concentrations. This inhibition was blocked by the 5-HT1A antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-2-pyridinylcyclohexanecarboxamide (WAY-100635), which was ineffective on its own, whereas the excitation was reversed by granisetron. The addition of citalopram or D-22 caused inhibition, which was prevented by 5-HT1A blockade. Thus, in the NTS, the spontaneous release of 5-HT is able to activate 5-HT3 receptors, but not 5-HT1A receptors, as the release in their vicinity is removed by uptake. The ineffectiveness of corticosterone suggests that the low-affinity, high-capacity transporter is PMAT, not OCT3. For evoked 5-HT release, only D-22 caused an increase in the amplitude of EPSCs, with a decrease in the paired pulse ratio, and increased the number of spontaneous EPSCs after 20-Hz stimulation. Thus, for the evoked release of 5-HT, the low-affinity, high-capacity transporter PMAT, but not 5-HT transporter (5-HTT)/SERT, is important in the regulation of changes in 5-HT extracellular concentration.

  7. Attenuation of hyperalgesia responses via the modulation of 5-hydroxytryptamine signalings in the rostral ventromedial medulla and spinal cord in a 6-hydroxydopamine-induced rat model of Parkinson’s disease

    PubMed Central

    Wang, Chen-Tao; Mao, Cheng-Jie; Zhang, Xiao-Qi; Zhang, Cai-Yi; Lv, Dong-Jun; Yang, Ya-Ping; Xia, Kai-Lin; Liu, Jun-Yi; Wang, Fen; Hu, Li-Fang; Xu, Guang-Yin

    2017-01-01

    Background Although pain is one of the most distressing non-motor symptoms among patients with Parkinson’s disease, the underlying mechanisms of pain in Parkinson’s disease remain elusive. The aim of the present study was to investigate the role of serotonin (5-hydroxytryptamine) in the rostral ventromedial medulla (RVM) and spinal cord in pain sensory abnormalities in a 6-hydroxydopamine-treated rat model of Parkinson’s disease. Methods The rotarod test was used to evaluate motor function. The radiant heat test and von Frey test were conducted to evaluate thermal and mechanical pain thresholds, respectively. Immunofluorescence was used to examine 5-hydroxytryptamine neurons and fibers in the rostral ventromedial medulla and spinal cord. High-performance liquid chromatography was used to determine 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels. Results The duration of running time on the rotarod test was significantly reduced in 6-hydroxydopamine-treated rats. Nociceptive thresholds of both mechanical and heat pain were reduced compared to sham-treated rats. In addition to the degeneration of cell bodies and fibers in the substantia nigra pars compacta, the number of rostral ventromedial medulla 5-hydroxytryptamine neurons and 5-hydroxytryptamine fibers in the spinal dorsal horn was dramatically decreased. 5-Hydroxytryptamine concentrations in both the rostral ventromedial medulla and spinal cord were reduced. Furthermore, the administration of citalopram significantly attenuated pain hypersensitivity. Interestingly, Intra-rostral ventromedial medulla (intra-RVM) microinjection of 5,7-dihydroxytryptamine partially reversed pain hypersensitivity of 6-hydroxydopamine-treated rats. Conclusions These results suggest that the decreased 5-hydroxytryptamine contents in the rostral ventromedial medulla and spinal dorsal horn may be involved in hyperalgesia in the 6-hydroxydopamine-induced rat model of Parkinson’s disease. PMID:28326933

  8. Fluvoxamine, a specific 5-hydroxytryptamine uptake inhibitor.

    PubMed

    Claassen, V; Davies, J E; Hertting, G; Placheta, P

    1977-08-01

    1. On the basis of both in vitro and in vivo experiments fluvoxamine has been characterized as a potential anti-depressant drug with almost exclusively 5-hydroxytryptamine (5-HT) uptake inhibiting properties. 2. Fluvoxamine is effective in inhibiting 5-ht uptake by blood platelets and brain synaptosomes. Due to inhibition of the membrane pump the compound prevents 5-HT depletion by the tyramine-derivatives H 75/12 and H 77/77. As a result of the interference with the neuronal re-uptake mechanism for 5-HT, fluvoxamine produces a decreased 5-HT turnover in the brain. Effects of 5-hydroxytryptophan (5-HTP) are potentiated in mice and in combination with pargyline, fluvoxamine induces 5-HT-like behavioural effects. 3. In contrast to tricyclic antidepressants, noradrenaline uptake processes are either unaffected or only slightly inhibited by fluvoxamine. The noradrenaline depleting effects of tyramine derivates are not influenced by fluvoxamine. Reserpine effects, such as ptosis are affected only at very high doses of the test compound. The antagonism by fluvoxamine of the reserpine-induced lowering of the pentamethylenetetrazole convulsive threshold can be regarded as due to an effect upon 5-HT uptake. In contrast to the effects of desmethylimipramine and imipramine, no stimulatory effects are found in rats when rapidly acting reserpine-like compounds are given following a dose of fluvoxamine.

  9. Fluvoxamine, a specific 5-hydroxytryptamine uptake inhibitor.

    PubMed Central

    Claassen, V; Davies, J E; Hertting, G; Placheta, P

    1977-01-01

    1. On the basis of both in vitro and in vivo experiments fluvoxamine has been characterized as a potential anti-depressant drug with almost exclusively 5-hydroxytryptamine (5-HT) uptake inhibiting properties. 2. Fluvoxamine is effective in inhibiting 5-ht uptake by blood platelets and brain synaptosomes. Due to inhibition of the membrane pump the compound prevents 5-HT depletion by the tyramine-derivatives H 75/12 and H 77/77. As a result of the interference with the neuronal re-uptake mechanism for 5-HT, fluvoxamine produces a decreased 5-HT turnover in the brain. Effects of 5-hydroxytryptophan (5-HTP) are potentiated in mice and in combination with pargyline, fluvoxamine induces 5-HT-like behavioural effects. 3. In contrast to tricyclic antidepressants, noradrenaline uptake processes are either unaffected or only slightly inhibited by fluvoxamine. The noradrenaline depleting effects of tyramine derivates are not influenced by fluvoxamine. Reserpine effects, such as ptosis are affected only at very high doses of the test compound. The antagonism by fluvoxamine of the reserpine-induced lowering of the pentamethylenetetrazole convulsive threshold can be regarded as due to an effect upon 5-HT uptake. In contrast to the effects of desmethylimipramine and imipramine, no stimulatory effects are found in rats when rapidly acting reserpine-like compounds are given following a dose of fluvoxamine. PMID:302726

  10. Increased 5-hydroxytryptamine mediates post-inflammatory visceral hypersensitivity via the 5-hydroxytryptamine 3 receptor in rats.

    PubMed

    Choi, Yun-Dong; Sung, Tae-Sik; Kim, Hyun-Ju; La, Jun-Ho; Kim, Tae-Wan; Yang, Il-Suk

    2008-11-01

    Visceral hypersensitivity often develops after intestinal inflammation, but the pathogenic mechanism has not been clearly elucidated. We investigated whether this post-inflammatory visceral hypersensitivity is mediated by 5-hydroxytryptamine through activation of the 5-hydroxytryptamine 3 receptor. In male Sprague-Dawley rats recovered from acetic acid-induced colitis, we monitored visceral nociceptive response by scoring the abdominal withdrawal reflex and simultaneously measuring the changes in arterial pulse rate. Seven days after induction of colitis, 52% of the rats showed an increased abdominal withdrawal reflex score and arterial pulse rate changes to colorectal distension, indicating that they had post-inflammatory visceral hypersensitivity. The 5-hydroxytryptamine 3 receptor antagonists, alosetron (20 mg/kg, p.o.) and granisetron (10 microg/kg, s.c.), inhibited post-inflammatory visceral hypersensitivity. Administration of a 5-hydroxytryptamine precursor, 5-hydroxytryptophan; 10 mg/kg, s.c.), induced visceral hypersensitivity in naïve rats, which was antagonized by granisetron. Increase in 5-hydroxytryptamine immunoreactive cells in colonic mucosal layer was found both in the rats with post-inflammatory visceral hypersensitivity and in the 5-hydroxytryptophan-treated rats. These results suggest that increased 5-hydroxytryptamine in colonic mucosa mediates post-inflammatory visceral hypersensitivity through activation of the 5-hydroxytryptamine 3 receptor.

  11. 5-hydroxytryptamine induced relaxation in the pig urinary bladder neck

    PubMed Central

    Recio, Paz; Barahona, María Victoria; Orensanz, Luis M; Bustamante, Salvador; Martínez, Ana Cristina; Benedito, Sara; García-Sacristán, Albino; Prieto, Dolores; Hernández, Medardo

    2009-01-01

    Background and purpose 5-Hydroxytryptamine (5-HT) is one of the inhibitory mediators in the urinary bladder outlet region. Here we investigated mechanisms involved in 5-HT-induced relaxations of the pig bladder neck. Experimental approach Urothelium-denuded strips of pig bladder were mounted in organ baths for isometric force recordings of responses to 5-HT and electrical field stimulation (EFS). Key results After phenylephrine-induced contraction, 5-HT and 5-HT receptor agonists concentration-dependently relaxed the preparations, with the potency order: 5-carboxamidotryptamine (5-CT) > 5-HT = RS67333 > (±)-8-hydroxy-2-dipropylaminotetralinhydrobromide > m-chlorophenylbiguanide > α-methyl-5-HT > ergotamine. 5-HT and 5-CT relaxations were reduced by the 5-HT7 receptor antagonist (2R)-1-[(3-hydroxyphenyl)sulphonyl]-2-[2-(4-methyl-1-piperidinyl)ethyl]pyrrolidine hydrochloride and potentiated by (S)-N-tert-butyl-3-(4-(2-methoxyphenyl)-piperazin-1-yl)-2-phenylpropanamide dihydrochloride (WAY 100135) and cyanopindolol, 5-HT1A and 5-HT1A/1B receptor antagonists respectively. Inhibitors of 5-HT1B/1D, 5-HT2, 5-HT2B/2C, 5-HT3, 5-HT4, 5-HT5A and 5-HT6 receptors failed to modify 5-HT responses. Blockade of monoamine oxidase A/B, noradrenergic neurotransmission, α-adrenoceptors, muscarinic and purinergic receptors, nitric oxide synthase, guanylate cyclase and prostanoid synthesis did not alter relaxations to 5-HT. Inhibitors of Ca2+-activated K+ and ATP-dependent K+ channels failed to modify 5-HT responses but blockade of neuronal voltage-gated Na+-, Ca2+-and voltage-gated K+ (Kv)-channels potentiated these relaxations. Adenylyl cyclase activation and cAMP-dependent protein kinase (PKA) inhibition potentiated and reduced, respectively, 5-HT-induced responses. Under non-adrenergic, non-cholinergic, non-nitrergic conditions, EFS induced neurogenic, frequency-dependent, relaxations which were resistant to WAY 100135 and cyanopindolol. Conclusions and implications 5-HT relaxed

  12. An examination of 5-hydroxytryptamine receptors in human saphenous vein.

    PubMed Central

    Docherty, J. R.; Hyland, L.

    1986-01-01

    We have examined the effects of antagonists on the isometric contraction of the human saphenous vein produced by 5-hydroxytryptamine (5-HT). The 5-HT2-antagonist ketanserin (1 microM) had little effect on the lower part of the concentration-response curve to 5-HT, but markedly shifted the upper part of the curve. Yohimbine caused an approximately parallel shift of the concentration-response curve to 5-HT, with a pA2 of 5.48, much lower than its pA2 against noradrenaline in the absence (6.36) or presence (7.06) of cocaine. It is concluded that there are two components to the contractile response to 5-HT in human saphenous vein: at low concentrations 5-HT activates a yohimbine-sensitive receptor, and at higher concentrations 5-HT activates a 5-HT2-receptor. PMID:3801780

  13. Pharmacological properties of phenyldiguanide and other amidine derivatives in relation to those of 5-hydroxytryptamine

    PubMed Central

    Fastier, F. N.; McDowall, M. A.; Waal, Hendrieka

    1959-01-01

    Cats in which the coronary and allied chemoreflexes could not be obtained with small intravenous doses of 5-hydroxytryptamine were insensitive also to phenyldiguanide. In cats which responded to phenyldiguanide with reflex falls of blood pressure and heart rate, abolished by vagotomy, the effects of graded doses (5 to 150 μg./kg.) of phenyldiguanide bore a striking resemblance to those produced initially by 5-hydroxytryptamine in somewhat smaller doses. Differences in the cardiovascular responses to the two drugs are attributed to additional (non-reflex) actions of 5-hydroxytryptamine. The reflex actions of both drugs were blocked reversibly also by 2-naphthylguanidine (500 μg.). Certain other drugs (bufotenine, procaine, S-decylisothiourea) antagonized the depressor action of phenyldiguanide as well as the reflex depressor action of 5-hydroxytryptamine. Like 5-hydroxytryptamine, phenyldiguanide and certain other amidine derivatives caused pain when applied to the base of blisters in human subjects. Unlike 5-hydroxytryptamine, phenyldiguanide did not constrict perfused rat blood vessels or increase the tone of the rat fundal strip preparation of Vane (1957). Phenyldiguanide did not affect the sensitivity of these smooth muscle preparations to 5-hydroxytryptamine, but other amidine derivatives proved to be moderately strong antagonists of the vasoconstrictor actions of 5-hydroxytryptamine and of adrenaline. Unlike 5-hydroxytryptamine, phenyldiguanide did not produce gastric haemorrhage in the mouse. Phenyldiguanide did not prolong chloral hydrate sleeping time in mice by the same mechanism as did 5-hydroxytryptamine. Phenyldiguanide was not highly toxic to mice (LD50 being 240 mg./kg.). It is concluded that phenyldiguanide and certain other amidine derivatives act on sensory receptors which respond to 5-hydroxytryptamine, but that they show little pharmacological resemblance to 5-hydroxytryptamine in other respects. PMID:13821683

  14. The effect of altered 5-hydroxytryptamine levels on beta-endorphin

    NASA Technical Reports Server (NTRS)

    Soliman, Karam F. A.; Mash, Deborah C.; Walker, Charles A.

    1986-01-01

    The purpose of the present study was to examine the effect of altering the concentration of 5-hydroxytryptamine (5-HT) on beta-endorphin (beta-Ep) content in the hypothalamus, thalamus, and periaqueductal gray (PAG)-rostral pons regions of the rat brain. The selective 5-HT reuptake inhibitor, fluoxetine (10 mg/kg), significantly lowered beta-Ep content in the hypothalamus and the PAG. Parachlorophenylalanine, which inhibits 5-HT synthesis, significantly elevated beta-Ep in all brain parts studied. Intracisternal injections of the neurotoxin 5-prime, 7-prime-dihydroxytryptamine with desmethylimipramine pretreatment significantly increased beta-Ep content in the hypothalamus and the PAG. In adrenalectomized rats, fluoxetine significantly decreased beta-Ep levels in the hypothalamus and increased the levels in the PAG. The results indicate that 5-HT may modulate the levels of brain beta-Ep.

  15. The effect of altered 5-hydroxytryptamine levels on beta-endorphin

    NASA Technical Reports Server (NTRS)

    Soliman, Karam F. A.; Mash, Deborah C.; Walker, Charles A.

    1986-01-01

    The purpose of the present study was to examine the effect of altering the concentration of 5-hydroxytryptamine (5-HT) on beta-endorphin (beta-Ep) content in the hypothalamus, thalamus, and periaqueductal gray (PAG)-rostral pons regions of the rat brain. The selective 5-HT reuptake inhibitor, fluoxetine (10 mg/kg), significantly lowered beta-Ep content in the hypothalamus and the PAG. Parachlorophenylalanine, which inhibits 5-HT synthesis, significantly elevated beta-Ep in all brain parts studied. Intracisternal injections of the neurotoxin 5-prime, 7-prime-dihydroxytryptamine with desmethylimipramine pretreatment significantly increased beta-Ep content in the hypothalamus and the PAG. In adrenalectomized rats, fluoxetine significantly decreased beta-Ep levels in the hypothalamus and increased the levels in the PAG. The results indicate that 5-HT may modulate the levels of brain beta-Ep.

  16. Kinetics of platelet 5-hydroxytryptamine uptake in headache patients.

    PubMed

    Hannah, P; Jarman, J; Glover, V; Sandler, M; Davies, P T; Clifford Rose, F

    1991-07-01

    Platelet 5-hydroxytryptamine (5-HT) uptake was measured in asymptomatic headache patients attending a specialist migraine clinic, and in hospital staff who did not suffer from regular or severe headache. Current levels of anxiety and depression were assessed in all subjects using the Hospital Anxiety and Depression (HAD) scale and their possible influence on the uptake kinetics taken into account during the analysis of results. The Michaelis-Menten constant (Km) was significantly raised in common migraine and tension headache compared with controls (p less than 0.001 and p less than 0.01, respectively), but not in classical migraine or cluster headache. The increase remained significant after adjusting for differences in age, sex, presence of anxiety or depression (HAD sub-scale score greater than or equal to 8), drug intake during the week before testing, time elapsed since last attack and time of assay (am or pm). No differences were observed between patients and controls in the maximal rate of uptake (Vmax) or platelet count, and previous reports of a reduction in Vmax in patients experiencing attack within 5 days prior to testing could not be confirmed. The cause and significance of an increased Km are not clear, but plasma factors acting as competitive inhibitors for the uptake site or an alteration in the configuration of the uptake site are possible explanations. If confirmed, the shared biochemical abnormality may suggest that common migraine and tension headache have a common pathogenesis.

  17. 5-Hydroxytryptamine receptor in rabbit aorta: characterization by butyrophenone analogs.

    PubMed

    Maayani, S; Wilkinson, C W; Stollak, J S

    1984-05-01

    The contractile response of isolated rabbit aorta rings to 5-hydroxytryptamine (5-HT) was antagonized by spiperone and four other butyrophenone analogs in a competitive manner. The Kb values were (nanomolar):spiperone, 0.8; spirilene , 2.1; benperidol , 4.4; azaperone, 16.6; and haloperidol, 96.6. The Kd values for four of these drugs, whose affinities for [3H]ketanserin and [3H]spiperone binding sites in rat brain membranes have been measured, are almost indistinguishable from the Kb values in inhibiting 5-HT-induced contraction of the rabbit aorta. This suggests a congruence between the aortic "D" receptors and 5-HT2 type binding sites in rat brain. Among the drugs we tested, one portion of the molecule is almost identical; the other portion of the molecule differs in four of the five compounds. It is suggested that their rank order as antagonists of the 5-HT receptor in the aorta depends on the degree of recognition of the nonbutyrophenone part of the molecules by the receptor.

  18. Amantadin e tremor, a 5-hydroxytryptamine-mediated response?

    PubMed

    Cox, B; Tha, S J

    1975-02-01

    Amantadine-induced tremor has been investigated using mice. Experiments with, mebanazine, reserpine, diethyldithiocarbamate, and p-chlorophenylalanine suggest that the tremorgenic action of amantadine is influenced by a balance between three putative central nervous system (CNS) transmitters: noradrenaline, dopamine and 5-hydroxytryptamine (5-HT). Drugs which reduce the concentration of the catecholamines in brain increase amantadine induced tremor. p-Chlorophenylalanine, which specifically depletes brain 5-HT, antagonises amantadine-induced tremor. An ED50 (tremor) dose of amantadine decreases the concentration of 5-hydroxy-indoleacetic acid (5-HIAA) in rat brain, particularly when this elevated due to pretreatment with 5-hydroxytryptophan. Neither inhibition of monoamine oxidase nor reduction of 5-HT-reuptake appear to be responsible for this decrease. Experiments on rat fundus suggest that amantadine increased the sensitivity of receptors to 5-HT. A similar mechanism of action in the CNS could explain both the tremor and the decrease in brain 5-HIAA. The possible relevance of these findings is discussed with respect to the known anti-Parkinson action of amantadine.

  19. The interplay between brain 5-hydroxytryptamine levels and cocaine addiction.

    PubMed

    Nonkes, Lourens J P; van Bussel, Inge P G; Verheij, Michel M M; Homberg, Judith R

    2011-12-01

    Cocaine addiction is a major health problem that affects millions of people. Cocaine acts by inhibiting dopamine, noradrenaline and serotonin [5-hydroxytryptamine(5-HT)] reuptake. The dopaminergic system is generally assumed to be involved in the reinforcing aspects of the drug, but the role of 5-HT in the addictive potential of cocaine is unclear. In light of pharmacological manipulations and cocaine use-related disease states affecting brain 5-HT levels, we review studies on the effect of cocaine on central 5-HT function. In addition, the contribution of 5-HT to the rewarding, aversive, discriminative and subjective, as well as the motivational and reinforcing effects of cocaine is discussed. We specifically focus on net changes in the extracellular 5-HT levels that occur as a consequence of acute and chronic cocaine exposure and how these influence cocaine abuse-related behaviour. Overall, the data indicate that 5-HT plays a major role in the psychomotor stimulant, rewarding and discriminative stimulant effects of cocaine, but also affects the motivational and reinforcing effects of the drug. In addition, 5-HT mediates, to some extent, the aversive effects of cocaine. Difficulties with data interpretation are discussed.

  20. Effects of 5-hydroxytryptamine on canine isolated coronary arteries.

    PubMed Central

    Porquet, M. F.; Pourrias, B.; Santamaria, R.

    1982-01-01

    The effects of 5-hydroxytryptamine (5-HT) were studied in vitro on proximal and distal portions of canine interventricular and circumflex coronary arterial strips. 5-HT produced concentration-related contractions in the proximal portion whether contracted previously with KCl or not. These responses were still present after either chemical sympathetic denervation or release of noradrenaline induced by K+-free salt solution. In contrast, the distal portions of coronary arteries did not respond to 5-HT. Concentration-response curves to 5-HT exhibited a classical hyperbolic shape with a calculated Hill-coefficient of approximately 1. Methysergide and phentolamine but not morphine shifted to the right and depressed the maximum of the dose-response curves to 5-HT. It is concluded that the contractions produced by 5-HT in the proximal portion of the interventricular and circumflex coronary arteries are not due to the release of endogenous noradrenaline. The vessels appear to possess separate receptors for 5-HT and noradrenaline and the 5-HT responses belong to neither the M nor the D type. PMID:7186819

  1. 5-Hydroxytryptamine-induced tachycardia in the pig: possible involvement of a new type of 5-hydroxytryptamine receptor.

    PubMed Central

    Bom, A. H.; Duncker, D. J.; Saxena, P. R.; Verdouw, P. D.

    1988-01-01

    1. The mechanism of 5-hydroxytryptamine (5-HT)-induced tachycardia is species-dependent and is mediated directly or indirectly either by '5-HT1-like' (cat), 5-HT2 (rat, dog) or 5-HT3 (rabbit) receptors, or by an action similar to tyramine (guinea-pig). The present investigation is devoted to the analysis of the positive chronotropic effect of 5-HT in the pentobarbitone-anaesthetized pig. 2. Intravenous bolus injections of 5-HT (3, 10 and 30 micrograms kg-1) in pigs resulted in dose-dependent increases in heart rate of 24 +/- 2, 38 +/- 3 and 51 +/- 3 beats min-1, respectively (n = 39). Topical application of a high concentration of 5-HT (150 micrograms kg-1 in 5 ml) on the right atrium was also followed by tachycardia (38 +/- 6 beats min-1, n = 4). 3. A number of drugs which antagonize responses mediated by different 5-HT receptors--phenoxybenzamine, methiothepin, metergoline, methysergide and mesulergine ('5-HT1-like' and 5-HT2 receptors), ketanserin, cyproheptadine, pizotifen and mianserin (5-HT2 receptors), and MDL 72222 and ICS 205-930 (5-HT3 receptors)--did not attenuate the chronotropic responses to 5-HT. 4. The 5-HT-induced tachycardia was also not affected by antagonists at alpha- and beta-adrenoceptors, muscarinic, nicotinic, histamine and dopamine receptors, and calcium channels. 5. Selective inhibitors of 5-HT-uptake, indalpine and fluvoxamine, themselves increased porcine heart rate and facilitated 5-HT-induced tachycardia both in magnitude and in duration.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3370393

  2. Interaction between tricyclic and nontricyclic 5-hydroxytryptamine uptake inhibitors and the presynaptic 5-hydroxytryptamine inhibitory autoreceptors in the rat hypothalamus.

    PubMed

    Galzin, A M; Moret, C; Verzier, B; Langer, S Z

    1985-10-01

    In slices of the rat hypothalamus prelabeled with [3H]-5-hydroxytryptamine [( 3H]-5-HT), exposure to lysergic acid diethylamide or 5-methoxytryptamine decreased, in a concentration-dependent manner, the release of 3H-transmitter elicited by electrical stimulation. These inhibitory effects were antagonized by the 5-HT receptor antagonist methiothepin (1 microM). Exposure to methiothepin on its own increased in a concentration-dependent manner the electrically evoked overflow of [3H]-5-HT. Exposure to tricyclic antidepressants, like imipramine and amitriptyline, and to nontricyclic 5-HT uptake inhibitors, like paroxetine and citalopram, did not modify by themselves the electrically evoked overflow of [3H]-5-HT. Yet, the four inhibitors of neuronal uptake of 5-HT, antagonized the inhibition by lysergic acid diethylamide or 5-methoxytryptamine of the electrically induced release of [3H]-5-HT. After depletion of endogenous stores of 5-HT by pretreatment with para-chlorophenylalanine (300 mg/kg i.p.), the inhibitors of 5-HT uptake increased the electrically evoked release of [3H]-5-HT in a concentration-dependent manner. Their order of potency to enhance 5-HT overflow after pretreatment with parachlorophenylalanine paralleled their potency at inhibiting neuronal uptake of 5-HT (paroxetine = citalopram greater than imipramine greater than amitriptyline). In para-chlorophenylalanine-treated rat hypothalamic slices, these inhibitors of 5-HT uptake antagonized the inhibition by 5-HT autoreceptor agonists of the electrically evoked release of [3H]-5-HT to a similar extent than was observed in control rats. It is concluded that inhibition of 5-HT uptake reduces the effectiveness of 5-HT autoreceptor agonists to inhibit the electrically evoked release of [3H]-5-HT, irrespective of the chemical structure of the uptake inhibitor or of the levels of endogenous 5-HT achieved in the synaptic gap.

  3. 5-hydroxytryptamine2C receptor activation inhibits 5-hydroxytryptamine1B-like receptor function via arachidonic acid metabolism.

    PubMed

    Berg, K A; Maayani, S; Clarke, W P

    1996-10-01

    We previously reported that in Chinese hamster ovary (CHO) cells, 5-hydroxytryptamine (5-HT)1B-like (CHO/5-HT1B) receptor-mediated inhibition of forskolin-stimulated cAMP accumulation is inhibited by activation of transfected human 5-HT2C receptors but not 5-HT2A receptors. In the current study, we investigated the mechanism involved in the regulation of receptor-mediated inhibition of adenylyl cyclase as a means to further elucidate differences between the signal transduction cascades of the 5-HT2A and 5-HT2C receptor subtypes. Activation of 5-HT2C receptors with 5-HT or (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane increased release of arachidonic acid via a phospholipase A2 (PLA2)-dependent mechanism. Incubation with (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (1 microM) abolished 5-carboxamidotryptamine (5 nM)-mediated inhibition of forskolin-stimulated cAMP accumulation, which was blocked by the PLA2 inhibitor mepacrine (100 microM) and the cyclooxygenase inhibitor indomethacin (2 microM). Furthermore, purinergic receptor-mediated PLA2 activation as well as direct activation of PLA2 with melittin reduced CHO/5-HT1B responsiveness. These data indicate that activation of the PLA2/arachidonic acid signaling cascade mediates 5-HT2C receptor regulation of the CHO/5-HT1B receptor pathway. Consistent with our previous report and in contrast to activation of 5-HT2C or purinergic receptors, activation of 5-HT2A receptors had no effect on CHO/5-HT1B receptor function, although 5-HT2A receptor-mediated activation of PLA2 was measured. Interestingly, purinergic receptor-mediated inhibition of CHO/5-HT1B receptor function was blocked when 5-HT2A receptors were activated simultaneously. These data suggest that the lack of 5-HT2A mediated regulation of CHO/5-HT1B receptors may be due to activation of a third pathway (in addition to PLC and PLA2 pathways), which results in the inhibition of the production or the actions of a cyclooxygenase-dependent arachidonic

  4. Effect of α-alkylated tryptamine derivatives on 5-hydroxytryptamine metabolism in vivo

    PubMed Central

    Gey, K. F.; Pletscher, A.

    1962-01-01

    In rats, three α-alkylated tryptamine derivatives (α-methyl, α-ethyl, and αα-dimethyltryptamine) caused alterations of 5-hydroxytryptamine metabolism typical of monoamine-oxidase inhibitors with short duration of action, viz., an increase of endogenous 5-hydroxytryptamine in brain, enhancement of the increase of 5-hydroxytryptamine in brain and heart after 5-hydroxytryptophan administration, an inhibition of the decrease in 5-hydroxytryptamine in brain induced by a benzoquinolizine derivative and of the increase induced by iproniazid. The increase after iproniazid was antagonized to the same extent by all the tryptamine derivatives and by harmaline, whereas dexamphetamine showed less effect. In the other experiments with brain, the tryptamine derivatives were less potent than harmaline, but somewhat more active than dexamphetamine. α-Methyltryptamine and α-ethyltryptamine were relatively more effective in the heart than in the brain. Among the tryptamine derivatives αα-dimethyltryptamine had the weakest activity in brain and in heart. PMID:13898151

  5. Effect of hemorrhagic shock on 5-hydroxytryptamine removal by the lung

    SciTech Connect

    Kerstein, M.D.; Cronau, L.H.; Mandel, S.D.; Gillis, C.N.

    1982-12-01

    The biogenic amine, radioactive 5-hydroxytryptamine, is removed from the blood during passage through the pulmonary vasculature. After one hour of hemorrhagic shock, the extraction rate increased from 74 to 89 per cent. One and two hours after resuscitation, the lung extracted only 30 per cent of the 5-hydroxytryptamine. The relationship between the pathophysiologic state and altered amine removal is a reflection of prolonged exposure to receptor sites or increased diffusion of serotonin across the endothelium.

  6. Cerebral circulatory and metabolic effects of 5-hydroxytryptamine in anesthetized baboons.

    PubMed Central

    Harper, M A; MacKenzie, E T

    1977-01-01

    1. The cerebral circulatory effects of the intracarotid administration of 5-hydroxytryptamine were examined in anaesthetized baboons. Cerebral blood flow was measured by the intracarotid 133Xe technique, cerebral O2 consumption and glucose uptake were measured as indices of brain metabolism and electrocortical activity was continuously monitored. 2. Despite a marked reduction in the calibre of the internal carotid artery (assessed angiographically), the intracarotid infusion of 5-hydroxytryptamine 0-1 microgram/kg. min did not effect any significant changes in cerebral blood flow, O2 consumption or glucose uptake. 3. Following transient osmotic disruption of the blood-brain barrier with the intracarotid infusion of hypertonic urea, the same dose of 5-hydroxytryptamine effected a marked reduction in cerebral blood flow from 51 +/- 2 to 36 +/- 2 ml./100 g. min (mean +/- S.E.; P less than 0-01). Both indices of cerebral metabolism were reduced significantly and the e.e.g. showed a more pronounced suppression-burst pattern. 4. We postulate that the cerebral circulatory responses to 5-hydroxytryptamine are dependent upon the integrity of the blood-brain barrier and the predominant effect of the intravascular administration of 5-hydroxytryptamine is on cortical activity or metabolism, rather than on cerebrovascular smooth muscle. Images Plate 1 PMID:411921

  7. The bacterial flora of the intestine of Ascaris suum and 5-hydroxytryptamine production.

    PubMed

    Hsu, S C; Johansson, K R; Donahue, M J

    1986-08-01

    Representative facultative anaerobes of the bacterial flora from the intestine of female Ascaris suum were isolated and identified. The number of bacteria in the intestine was approximately 4 X 10(9) per g wet weight of intestine. Seventeen of 19 of the isolated colonies were found to secrete 5-hydroxytryptamine in culture. Holding A. suum in an antibiotic-containing medium did not affect the levels of 5-hydroxytryptamine in the worm, which were 231 +/- 14 ng/g in antibiotic-media as compared to 250 +/- 16 ng/g in control media. This implied that the bacteria may not be contributing to the level of 5-hydroxytryptamine in the tissues of A. suum.

  8. Ethanol Stabilizes the Open State of Single 5-Hydroxytryptamine3A(QDA) Receptors

    PubMed Central

    Feinberg-Zadek, Paula L.

    2010-01-01

    Ethanol enhancement of 5-hydroxytryptamine (5-HT)3A receptor-mediated responses may have important consequences in the intoxicating and addictive properties of ethanol. Although the exact mechanism is unknown, ethanol-mediated enhancement of 5-HT3 receptor current has been proposed to occur due to stabilization of the open-channel state. It has not been possible to directly measure the open state of the channel due to the extremely low single-channel conductance of 5-HT3A channels. Recently, three arginine residues within the large intracellular loop of the 5-HT3A subunit were substituted by their equivalent residues (glutamine, aspartate, and alanine) of the 5-HT3B subunit to produce a 5-HT3A(QDA) subunit that forms functional homomeric channels exhibiting a measurable single-channel conductance. Using whole-cell rapid-agonist application techniques and the cell-attached single-channel recording configuration, we examined human 5-HT3A(QDA) receptors expressed in human embryonic kidney 293 cells. The agonist sensitivity, macroscopic kinetics, and modulation by ethanol were similar between mutant and wild-type channels, suggesting the substitutions had not altered these channel structure-function properties. The open time histogram for single-channel events mediated by 5-HT3A(QDA) receptors in the presence of maximal 5-HT was best fit by three exponentials, but in the presence of ethanol a fourth open state was evident. In summary, the QDA substitution greatly enhanced single-channel conductance with little effect on 5-HT3A channel's kinetic properties and ethanol enhances agonist action on 5-HT3A receptors by inducing a new, long-lived open-channel state. Furthermore, the 5-HT3A(QDA) receptor appears to be suitable for pharmacological studies of 5-HT3A receptor modulation at a single-channel level. PMID:20200118

  9. Effects of 5-hydroxytryptamine on the dorsal muscle of the leech (hirudo medicinalis)

    PubMed Central

    Schain, R. J.

    1961-01-01

    5-Hydroxytryptamine has an inhibiting effect on the leech muscle. It reduces the contractions produced by acetylcholine or nicotine and accelerates the relaxation of the muscle when these substances are washed out. This acceleration of relaxation allows a more rapid assay of acetylcholine in this preparation. PMID:13747232

  10. 5-Hydroxytryptamine receptor in isolated rabbit aorta: characterization with tryptamine analogs.

    PubMed

    Clancy, B M; Maayani, S

    1985-06-01

    The 5-HT2 receptor in isolated rabbit thoracic aorta was characterized by examining the relationships between structure and activity of nine tryptamine analogs. All assays were conducted after blockade of the alpha adrenergic receptor and inactivation of the neuronal uptake-1 system and monoamine oxidase. Seven of the analogs tested were agonists. 6-Hydroxytryptamine and 7-hydroxytryptamine showed little or no agonist activity in this preparation. The pA2 of spiperone was independent of the agonist assayed and defined the receptor activated by each agonist as the 5-HT2 receptor. The dissociation constant (KA) and relative intrinsic efficacy were determined for each agonist. The KA and relative intrinsic efficacy values for 5-hydroxytryptamine were 0.25 microM and 1, respectively. The KA and relative intrinsic efficacy values for 5-methoxytryptamine were 0.14 microM and 0.86, respectively, and were not significantly different from those for 5-hydroxytryptamine. The other five analogs were partial agonists. N-Methyl-5-hydroxytryptamine and bufotenine had relative intrinsic efficacies of about 0.3 and KA values not statistically different from the KA value for 5-hydroxytryptamine. Tryptamine, 5-methyltryptamine and alpha-methyl-tryptamine had KA values of about 1 microM and relative intrinsic efficacies of 0.6, 0.6 and 0.4, respectively. These results revealed the differential effects of structural changes on drug affinity and intrinsic efficacy. This information will be applicable in the design of selective agonists or antagonists for the classification of less well defined 5-hydroxytryptamine receptors.

  11. Age-dependent effects of the 5-hydroxytryptamine-2a-receptor polymorphism (His452Tyr) on human memory.

    PubMed

    Papassotiropoulos, Andreas; Henke, Katharina; Aerni, Amanda; Coluccia, Daniel; Garcia, Esmeralda; Wollmer, Marc A; Huynh, Kim-Dung; Monsch, Andreas U; Stähelin, Hannes B; Hock, Christoph; Nitsch, Roger M; de Quervain, Dominique J-F

    2005-05-31

    A polymorphism (His452Tyr) of the 5-hydroxytryptamine (5-HT)2a receptor is associated with episodic memory in healthy young humans. Because 5-HT2a-receptor density decreases with increasing age, we tested whether the 5-HT2a receptor genotype effect on memory is influenced by age. We investigated the association of the His452Tyr genotype with memory performance in 622 healthy study participants aged from 18 to 90 years. In young to middle-aged participants, age significantly influenced genotype effects on episodic memory: the His452Tyr genotype exerted a significant influence on memory only in young participants. In the group of elderly cognitively healthy participants, the His452Tyr genotype did not affect memory performance. We conclude that age strongly modulates the effect of the 5-HT2a receptor polymorphism at residue 452 on episodic memory.

  12. Redistribution by 5-hydroxytryptamine of carotid arterial blood at the expense of arteriovenous anastomotic blood flow

    PubMed Central

    Saxena, Pramod R.; Verdouw, Pieter D.

    1982-01-01

    1. The effects of 5-hydroxytryptamine by intravenous (1, 5 and 10 μg kg-1 min-1 in cats) and intracarotid (0·5 and 2 μg kg-1 min-1 in pigs) routes were studied on the complete distribution of common carotid artery blood flow, measured with radioactive microspheres (15 μm). In addition, the amine was also infused (0·75-3 μg kg-1 min-1) into the carotid artery of cats to observe its influence on the shunting of microspheres in the jugular venous blood. 2. The basal total common carotid blood flow was distributed ipsilaterally mainly to extracerebral tissues and only little blood entered the brain. As shown by the presence of microspheres in the lungs after injection into the carotid artery (52% in cats; 82% in pigs), a major fraction of the carotid blood by-passed the capillary bed through arteriovenous anastomoses in the head (non-nutrient fraction). 3. 5-Hydroxytryptamine redistributed the blood in favour of the nutrient compartment at the expense of arteriovenous anastomotic fraction. In cats, tissue blood flow did not significantly change but, in the pig, blood flow to all tissues, particularly to skin and ears, was substantially increased despite a reduction in total carotid blood flow. This reduction was entirely due to a change in the non-nutrient fraction. 4. Intracarotid infusion of 5-hydroxytryptamine in vagosympathectomized intact or spinal cats decreased the number of microspheres appearing in the jugular venous blood, again indicating a reduction in arteriovenous anastomotic flow due to a constriction of these non-nutrient vessels. 5. Cyproheptadine (1 mg kg-1) completely reversed the effect of 5-hydroxytryptamine on the total carotid blood flow. However, the vasoconstriction of arteriovenous anastomoses was only partially attenuated and the vasodilatatory response was either unchanged (muscle) or even enhanced (skin, ear and bones). 6. It is suggested that 5-hydroxytryptamine causes vasoconstriction of the large arteries via D-receptors which are

  13. Evidence for a central 5-hydroxytryptamine receptor stimulation by lysergic acid diethylamide

    PubMed Central

    Andén, N.-E.; Corrodi, H.; Fuxe, K.; Hökfelt, T.

    1968-01-01

    1. Lysergic acid diethylamide (LSD) and the 5-hydroxytryptamine (5-HT) precursor, 5-hydroxytryptophan produced similar functional effects in rat spinal cord and brain to the 5-hydroxytryptamine precursor 5-hydroxytryptophan, which indicates that LSD stimulates central 5-HT receptors. 2. By means of combined histochemical and biochemical techniques it was found that LSD reduced the turnover rate of brain and spinal cord 5-HT, studied after inhibition of the tryptophan hydroxylase by α-propyldopacetamide. The turnover of brain noradrenaline but not dopamine was somewhat accelerated. 3. The functional and chemical effects by LSD were related to dose and to time. They were not observed after the LSD analogues 2-bromo-LSD and methylsergide. 4. The retardation of the 5-HT turnover by LSD may be due to negative feed-back mechanisms evoked by direct stimulation of the central 5-HT receptors. ImagesFIG. 1FIG. 2 PMID:5302837

  14. Release of ( sup 14 C)5-hydroxytryptamine from human platelets by red wine

    SciTech Connect

    Jarman, J.; Glover, V.; Sandler, M. )

    1991-01-01

    Red wine, at a final dilution of 1/50, caused released of ({sup 14}C)5-hydroxytryptamine (5-HT) from preloaded platelets, an effect which was not observed with any white wines or beers tested. Since 5-HT, is probably released from body stores during migraine attacks and red wine is known to provoke migraine episodes in susceptible individuals, release of 5-HT, possibly from central stores, could represent a plausible mechanism for its mode of action.

  15. The distribution of 5-hydroxytryptamine in the gastrointestinal tract of reptiles, birds and a prototherian mammal. An immunohistochemical study.

    PubMed

    Adamson, S; Campbell, G

    1988-03-01

    The distribution of 5-hydroxytryptamine in the gut of several species of birds and reptiles, and of a prototherian mammal, the platypus, was studied using a monoclonal antibody. 5-Hydroxytryptamine-like immunoreactivity was found in enterochromaffin cells and, in birds, in thrombocytes. Immunoreactivity was not found in enteric neurons fixed immediately after dissection. A detailed study was made on one avian species, the budgerigar. Following incubation of intestine in physiological solution, immunoreactivity was found in nerve fibres in the gut wall that was more marked after incubation with the monoamine oxidase inhibitor pargyline. These fibres took up exogenous 5-hydroxytryptamine. Similar fibres were found in the intestinal nerves and in perivascular plexuses on mesenteric arteries. Both the uptake of 5-hydroxytryptamine and the appearance of neuronal immunoreactivity after incubation were inhibited by the amine uptake inhibitors desmethylimipramine or fluoxetine. Fibres taking up 5-hydroxytryptamine were damaged by pretreatment with 6-hydroxydopamine. It was concluded that the fibres showing immunoreactivity after incubation were adrenergic fibres that had taken up 5-hydroxytryptamine released in vitro from enterochromaffin cells or thrombocytes. These, and more limited observations made on the other species, suggest that birds, reptiles and prototherian mammals lack enteric neurons that use 5-hydroxytryptamine as a transmitter substance.

  16. Influence of 5-hydroxytryptamine (serotonin) on blood flow in the dog pulp

    SciTech Connect

    Kim, S.; Trowbridge, H.O.; Dorscher-Kim, J.E.

    1986-05-01

    The effect of intra-arterial injection of 5-hydroxytryptamine (5-HT) on pulpal blood flow of the dog was determined using the 15-micron radioisotope-labeled microsphere injection method. Pulpal blood flow was significantly reduced following the 5-HT injection. This decrease in blood flow appeared to be due to vasoconstriction as determined by an increase in pulpal vascular hindrance. However, our findings do not preclude the possibility that blood flow was reduced as a result of passive compression of venules produced by vasodilation in a low-compliance environment.

  17. Polymorphisms in the 5-hydroxytryptamine receptor 3B gene are associated with heroin dependence in the Chinese Han population.

    PubMed

    Yin, Fangyuan; Ji, Yuanyuan; Zhang, Jing; Guo, Hao; Huang, Xin; Lai, Jianghua; Wei, Shuguang

    2016-12-02

    Previous studies suggested that the 5-hydroxytryptamine receptor 3B (HTR3B) is involved in heroin dependence by modulating dopamine (DA) release in the reward pathway and that the genetic polymorphisms in HTR3B play plausible role in modulating the risk of developing heroin addiction. To identify markers that contribute to the genetic susceptibility to heroin dependence, we examined the potential associations between heroin dependence and 7 single nucleotide polymorphisms (SNPs) of the HTR3B gene using multiplex SNaPshot technology in a Chinese Han population. Participants included 418 heroin-dependent subjects and 422 healthy controls. The results suggested that the genotype distribution of HTR3B rs1176746 and rs1185027 were significantly different between heroin dependent subjects and healthy controls (both p=0.004). The frequency of the GG of rs1176746 and AA of rs1185027 genotype in heroin-dependent subjects were significantly higher than that of healthy controls, while the GA of rs1176746 and AT of rs1185027 genotype distributions were much lower. Another SNP, rs10789970, showed a nominally significant p-value in the genotype distribution between heroin dependent subjects and controls (p=0.022). These findings indicate the important role of HTR3B polymorphisms in heroin dependence among the Chinese Han population and provide valuable information for further genetic and neurobiological investigations of heroin dependence. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. 5-Hydroxytryptamine Changes under Different Pretreatments on Rat Models of Myocardial Infarction and/or Depression

    PubMed Central

    Liu, Mei-Yan; Zhang, Li-Jun; Zhou, Yu-Xin; Wei, Wan-Lin

    2017-01-01

    Background: Psychocardiological researches have suggested a central role of 5-hydroxytryptamine (5-HT) on psychocardiological mechanism. This study aimed to further explore the central role of 5-HT and pretreatment effects of XinLingWan on rats with myocardial infarction (MI) and/or depression. Methods: Ninety Sprague-Dawley rats were randomly divided into three groups: MI group, depression group, and MI + depression group (n = 30 in each group). Each group was then divided into three subgroups (n = 10 in each subgroup): a negative control subgroup (NCS), a Western medicine subgroup (WMS), and a traditional Chinese medicine subgroup (TCMS), which were received pretreatment once a day for 4 weeks by saline, 20 mg/kg sertraline mixed with 2 ml saline, and 40 mg/kg XingLingWan mixed with 2 ml saline, respectively. Different rat models were established after different pretreatments. Rats were then sacrificed for detection of serum 5-HT, platelet 5-HT, 5-HT2A receptors (5-HT2AR), and serotonin transporter (SERT). Data were analyzed by one-way analysis of variance (ANOVA) and least-significant difference (LSD) testing. Results: MI group: compared with NCS, there was a significant increase in WMS and TCMS of serum 5-HT (176.15 ± 11.32 pg/ml vs. 334.50 ± 29.09 pg/ml and 474.04 ± 10.86 pg/ml, respectively, both P = 0.000), platelet 5-HT (129.74 ± 27.17 pg/ml vs. 322.24 ± 11.60 pg/ml and 340.4 5 ± 17.99 pg/ml, respectively, both P = 0.000); depression group: compared with NCS, there was a significant increase in WMS and TCMS of serum 5-HT (194.69 ± 5.09 pg/ml vs. 326.21 ± 39.98 pg/ml and 456.33 ± 23.12 pg/ml, respectively, both P = 0.000), platelet 5-HT (175.15 ± 4.07 pg/ml vs. 204.56 ± 18.59 pg/ml and 252.03 ± 22.26 pg/ml, respectively, P = 0.004 and P = 0.000, respectively); MI + depression group: compared with NCS, there was a significant increase in both WMS and TCMS of serum 5-HT (182.50 ± 10.23 pg/ml vs. 372.55 ± 52.23 pg/ml and 441.76 ± 23.38 pg

  19. Participation of a transmembrane proton gradient in 5-hydroxytryptamine transport by platelet dense granules and dense-granule ghosts.

    PubMed Central

    Wilkins, J A; Salganicoff, L

    1981-01-01

    Dense granules, the storage organelles for 5-hydroxytryptamine in blood platelets, have been isolated from porcine platelets and are shown to transport 5-hydroxytryptamine in response to a transmembrane proton gradient (delta pH). Transport in the absence of delta pH is minimal, and it is shown that a rapid increase in transport takes place as delta pH increases. Direct measurements with [14C]methylamine show a delta pH of 1.1 units (acid inside) for intact granules. Osmotically active ghosts of dense granules from which 95% of the endogenous 5-hydroxytryptamine content has been released have also been prepared. Ghosts swell in the presence of ATP and Mg2+, and this swelling is shown to be due to the entry of protons via a process linked to ATP hydrolysis. Proton entry is also apparently linked to anion penetration in ghosts. Steady-state 5-hydroxytryptamine transport in ghosts is stimulated approx. 3-fold on the addition of ATP to the incubation medium, and the stimulation of 5-hydroxytryptamine transport in ghosts correlates with the formation of a transmembrane delta pH. Ghosts generate a delta pH of 1.1-1.3 pH units (acid inside) in the presence of 5 mM-ATP/2.5 mM-MgSO4. delta pH is generated within 3 min at 37 degrees C and is dissipated by the ionophore nigericin and by NH4Cl. It is shown that an Mg2+-stimulated ATPase activity is present on the ghost membrane, and inhibition of the ATPase leads to a corresponding decrease in 5-hydroxytryptamine transport. The results presented support the idea that 5-hydroxytryptamine transport into platelet dense granules is dependent on the presence of a transmembrane delta pH and, together with previous findings by others, suggest a generalized mechanism for biogenic amine transport into subcellular storage organelles. Images Fig. 2. PMID:6459780

  20. Immunohistochemical localization of serotonin (5-hydroxytryptamine) in the gonad and digestive gland of Mya arenaria (Mollusca: Bivalvia).

    PubMed

    Garnerot, F; Pellerin, J; Blaise, C; Mathieu, M

    2006-12-01

    Serotonin (5-hydroxytryptamine or 5-HT) C(10)H(12)N(2)O plays a central role in several physiological processes in marine molluscs, especially in reproduction. 5-HT acts as a neurohormone to modulate spawning, parturition and meiosis by reinitiating prophase in arrested oocytes. Preliminary experiments using 10(-5)M 5-HT dissolved in aquarium water showed that 5-HT induced spawning movements in ripe clams and in both sexes of Mya arenaria while only a few males released sperm. The occurrence of serotoninergic fibers was demonstrated by PAP immunohistochemical reaction in the gonad of both sexes during gametogenesis. In an organism infected by the trematode parasite Prosorhynchus squamatus, we showed that serotoninergic innervation completely disappeared around the gonad's follicles. Although the gonad and digestive gland are intertwined, no serotoninergic innervations were found in the digestive gland. These findings suggest, for the first time to our knowledge in the soft shell clam, that serotonin might be involved in the regulation of gametogenesis.

  1. Effects of 5-hydroxytryptamine and 5-hydroxytryptamine 2A/2C agonist on the genioglossus activity and sleep apnea in rats.

    PubMed

    Zhong, Yi-jue; Zhang, Cheng; Wang, Guang-fa

    2010-08-05

    5-Hydroxytryptamine (5-HT) is a common neurotransmitter in the brain which plays an important role in the pathogenesis of sleep apnea. Dysfunction of 5-HT and 5-HT(2) receptors may lead to the collapse of the upper airway and the instability of respiratory control, which in turn produce apnea. Genioglossus (GG) is one of the most important oropharyngeal muscles maintaining the upper airway open. The present study aimed to investigate the effects of 5-HT and 5-HT(2) receptor on GG activity and the sleep apnea in Sprague-Dawley (SD) rats. Microinjection probes were placed within the fourth ventricle of sixteen SD rats. After recovery for a week, the electromyogram (EMG) of GG was recorded in the anesthetized and vagotomized rats. The changes of GG activity before and after the microinjection of 5-HT or 5-HT(2A/2C) agonist -2,5-dimethoxy-4-iodoamphetamine hydrochloride (DOI) were observed. Probes were also laid in another eight SD rats. Electroencephalogram (EEG), EMG of neck muscle and respiration were recorded at the same time a week later. The effects of DOI on the occurrence of sleep apnea were explored. Both 5-HT and DOI significantly enhanced the activity of GG just 3 minutes after the completion of injection. The effect of 5-HT disappeared quickly and the effect of DOI lasted for more than 27 minutes. DOI also significantly decreased the post-sigh apnea index in non-rapid-eye-movement (NREM) and rapid-eye-movement (REM) sleep and decreased the spontaneous apnea index only in NREM sleep (P < 0.05, respectively). 5-HT and 5-HT(2A/2C) system correlated closely with the pathogenesis of the sleep apnea syndrome and 5-HT receptors may become the target of the drug treatment.

  2. On the role of 5-hydroxytryptamine in drug-induced antinociception.

    PubMed Central

    Sugrue, M F

    1979-01-01

    1. The effects of four specific inhibitors of 5-hydroxytryptamine (K-HT) uptake on morphine-, methadone- or pethidine-induced antinociception was studied in rats. Antinociception was assessed by means of hot plate (55 degrees C) reaction times. The effect of the compounds on the uptake of [3H]-5-HT into rat whole brain synaptosomes was also investigated. 2. Pretreatment with Org 6582, citalopram, zimelidine or femoxetine at doses devoid of antinociceptive activity potentiated morphine- but not methadone- or pethidine-induced antinociception. 3. A temporal correlation existed between the ability of Org 6582 to potentiate morphine-induced antinociception and to block synaptosomal [3H]-5-HT uptake. 4. 5-HT plays a critical role in the antinociceptive effect of morphine but not of methadone or pethidine. PMID:435690

  3. Platelet 5-hydroxytryptamine release and aggregation promoted by cotton bracts tannin.

    PubMed

    Rohrbach, M S; Rolstad, R A; Tracy, P B; Russell, J A

    1984-01-01

    The effect of aqueous extracts of cotton bract (CBE) on platelet secretion and aggregation was examined by using washed bovine and human platelets. The CBE promoted the release of 75% to 90% of the 5-hydroxytryptamine (5-HT) stored in both human and bovine platelets in a dose-dependent manner. This release reaction occurred without the lysis of the platelets and was not inhibited by indomethacin, 2-deoxyglucose, or KCN. Fractionation of the CBE indicated that the platelet secretagogue present in the CBE was the condensed polyphenol, tannin. In addition to promoting the secretion of 5-HT, tannin also aggregated the platelets in a dose-dependent manner. We conclude that the secretion of platelet 5-HT and the aggregation of platelets by tannin could potentially contribute to the pulmonary symptoms associated with byssinosis.

  4. Feeding increases 5-hydroxytryptamine and norepinephrine within the hypothalamus of chicks.

    PubMed

    Tachibana, T; Tazawa, M; Sugahara, K

    2001-11-01

    It is thought that hypothalamic 5-hydroxytryptamine (5HT) and norepinephrine (NE) are involved in the regulation of feeding in chicks. The present study was conducted to elucidate changes in the levels of extracellular 5HT and NE in the hypothalamus during feeding of chicks. In order to measure 5HT, NE and 4-hydroxy-3-methoxyphenylglycol (MHPG), which is a major metabolite of NE, we used brain microdialysis and high-pressure liquid chromatography with an electrochemical detector. After collecting samples to determine the basal levels of 5HT, NE and MHPG, food-deprived birds were given access to food. 5HT levels in the medial hypothalamus (MH) and lateral hypothalamus (LH) increased during the first 30 min of feeding, and then returned to basal levels. NE and MHPG in the LH increased during feeding, and remained elevated throughout the experiment. This study supports an idea that hypothalamic monoamines in the chick brain are involved in the regulation of feeding.

  5. Iontophoretic release of acetylcholine, noradrenaline, 5-hydroxytryptamine and D-lysergic acid diethylamide from micropipettes

    PubMed Central

    Bradley, P. B.; Candy, J. M.

    1970-01-01

    1. The in vitro iontophoretic release of tritium-labelled acetylcholine and 5-hydroxytryptamine from large and small micropipettes and noradrenaline and D-lysergic acid diethylamide from small micropipettes was determined by liquid scintillation counting. 2. The release was directly proportional to the electrical charge passed in the range normally used in the iontophoretic study of these compounds. The transport numbers obtained for the large micropipettes were approximately double those with the small micropipettes. A very low transport number was found for D-lysergic acid diethylamide. 3. The spontaneous leakage was small and did not vary appreciably with time. 4. The iontophoretic release of acetylcholine in vitro agreed with the in vitro measurements. 5. The brain-stem tissue concentration of D-lysergic acid diethylamide after intravenous injection into intact and decerebrate cats was determined. PMID:5492892

  6. Repeated chlorpromazine administration increases a behavioural response of rats to 5-hydroxytryptamine receptor stimulation.

    PubMed Central

    Green, A R

    1977-01-01

    1 The hyperactivity syndrome produced in rats by administration of tranylcypromine (20 mg/kg i.p.) followed 30 min later by L-tryptophan (50 mg/kg i.p.) is generally considered to be due to increased 5-hydroxytryptamine (5-HT) functional activity. It is inhibited by chlorpromazine (30 mg/kg i.p.) injected 60 min before the tranylcypromine. However, chlorpromazine injection for 4 days either at a dose of 30 mg/kg once daily or 5 mg/kg twice daily results in an enhanced hyperactivity response to tranylcypromine and L-tryptophan administration 24 h after the final dose of chlorpromazine. 2 One injection of chlorpromazine (30 mg/kg) did not produce enhancement 24 h later and the inhibition of the tranylcypromine/L-tryptophan hyperactivity observed after acute chlorpromazine injection was seen if the rats were given tranylcypromine and L-tryptophan 1 h after the fourth chlorpromazine (30 mg/kg) dose. 3 Chlorpromazine (30 mg/kg) once daily or 5 mg/kg twice daily for 4 days resulted in rats displaying enhanced behavioral responses to the suggested 5-HT agonist 5-methoxy N,N-dimethyltryptamine (2 mg/kg) on day 5. 4 Chlorpromazine (30 mg/kg) once daily for 4 days produces a slight increase in brain 5-hydroxytryptamine (5-HT) concentration on day 5, but no difference in the rate of brain 5-HT synthesis or the rate of 5-HT accumulation after tranylcypromine and L-tryptophan administration. 5. There is some evidence that chlorpromazine blocks 5-HT receptors. It has also been observed that several other neuroleptic drugs do not produce enhanced 5-HT responses after repeated administration. It is suggested therefore that the enhanced behavioural response to 5-HT receptor stimulation following repeated chlorpromazine administration may be because this drug blocks 5-HT receptors. PMID:264797

  7. Depressive disorder and gastrointestinal dysfunction after myocardial infarct are associated with abnormal tryptophan-5-hydroxytryptamine metabolism in rats

    PubMed Central

    Liu, Chunyan; Wang, Yangang

    2017-01-01

    In this study, we investigated the relationship between tryptophan-5-hydroxytryptamine metabolism, depressive disorder, and gastrointestinal dysfunction in rats after myocardial infarction. Our goal was to elucidate the physiopathologic bases of somatic/psychiatric depression symptoms after myocardial infarction. A myocardial infarction model was established by permanent occlusion of the left anterior descending coronary artery. Depression-like behavior was evaluated using the sucrose preference test, open field test, and forced swim test. Gastric retention and intestinal transit were detected using the carbon powder labeling method. Immunohistochemical staining was used to detect indoleamine 2,3-dioxygenase expression in the hippocampus and ileum. High-performance liquid chromatography with fluorescence and ultraviolet detection determined the levels of 5-hydroxytryptamine, its precursor tryptophan, and its metabolite 5-hydroxyindoleacetic acid in the hippocampus, distal ileum, and peripheral blood. All data were analyzed using one-way analyses of variance. Three weeks after arterial occlusion, rats in the model group began to exhibit depression-like symptoms. For example, the rate of sucrose consumption was reduced, the total and central distance traveled in the open field test were reduced, and immobility time was increased, while swimming, struggling and latency to immobility were decreased in the forced swim test. Moreover, the gastric retention rate and gastrointestinal transit rate were increased in the model group. Expression of indoleamine 2,3-dioxygenase was increased in the hippocampus and ileum, whereas 5-hydroxytryptamine metabolism was decreased, resulting in lower 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels in the hippocampus and higher levels in the ileum. Depressive disorder and gastrointestinal dysfunction after myocardial infarction involve abnormal tryptophan-5-hydroxytryptamine metabolism, which may explain the somatic, cognitive

  8. Depressive disorder and gastrointestinal dysfunction after myocardial infarct are associated with abnormal tryptophan-5-hydroxytryptamine metabolism in rats.

    PubMed

    Lu, Xiaofang; Wang, Yuefen; Liu, Chunyan; Wang, Yangang

    2017-01-01

    In this study, we investigated the relationship between tryptophan-5-hydroxytryptamine metabolism, depressive disorder, and gastrointestinal dysfunction in rats after myocardial infarction. Our goal was to elucidate the physiopathologic bases of somatic/psychiatric depression symptoms after myocardial infarction. A myocardial infarction model was established by permanent occlusion of the left anterior descending coronary artery. Depression-like behavior was evaluated using the sucrose preference test, open field test, and forced swim test. Gastric retention and intestinal transit were detected using the carbon powder labeling method. Immunohistochemical staining was used to detect indoleamine 2,3-dioxygenase expression in the hippocampus and ileum. High-performance liquid chromatography with fluorescence and ultraviolet detection determined the levels of 5-hydroxytryptamine, its precursor tryptophan, and its metabolite 5-hydroxyindoleacetic acid in the hippocampus, distal ileum, and peripheral blood. All data were analyzed using one-way analyses of variance. Three weeks after arterial occlusion, rats in the model group began to exhibit depression-like symptoms. For example, the rate of sucrose consumption was reduced, the total and central distance traveled in the open field test were reduced, and immobility time was increased, while swimming, struggling and latency to immobility were decreased in the forced swim test. Moreover, the gastric retention rate and gastrointestinal transit rate were increased in the model group. Expression of indoleamine 2,3-dioxygenase was increased in the hippocampus and ileum, whereas 5-hydroxytryptamine metabolism was decreased, resulting in lower 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels in the hippocampus and higher levels in the ileum. Depressive disorder and gastrointestinal dysfunction after myocardial infarction involve abnormal tryptophan-5-hydroxytryptamine metabolism, which may explain the somatic, cognitive

  9. Effect of antibiotics on the 5-hydroxytryptamine content of the small intestine and other organs in rats and mice

    PubMed Central

    Sullivan, T. J.

    1961-01-01

    Rats and mice were given antibiotics orally and by subcutaneous injection and the effects on tissue levels of 5-hydroxytryptamine and intestinal bacteria were studied. In mice it was found that antibiotics which caused a large reduction in the bacterial flora of the intestine when given orally also caused a significant increase in intestinal 5-hydroxytryptamine. In rats, neomycin caused a reduction in the urinary excretion of 5-hydroxyindoleacetic acid. In both rats and mice, many antibiotics caused a significant reduction in the weight of the spleen. PMID:19108146

  10. The effect of lysergic acid diethylamide, 5-hydroxytryptamine, and related compounds on the liver fluke, fasciola hepatica

    PubMed Central

    Mansour, T. E.

    1957-01-01

    The rhythmical activity of the liver fluke, Fasciola hepatica, was stimulated by 5-hydroxytryptamine and by lysergic acid diethylamide at very low concentrations. The effect was peripheral and was not mediated through the central ganglion. Other amines also stimulated rhythmical activity, the most potent being the indolamines. Bromolysergic acid diethylamide, and other analogues such as yohimbine, harmine, and dopamine depressed rhythmical movement and antagonized the stimulant action of 5-hydroxytryptamine and lysergic acid diethylamide. Evidence which suggests the presence of tryptamine receptors in the trematode is discussed. PMID:13489165

  11. 5-Hydroxytryptamine2A/2C receptors of nucleus raphe magnus and gigantocellularis/paragigantocellularis pars α reticular nuclei modulate the unconditioned fear-induced antinociception evoked by electrical stimulation of deep layers of the superior colliculus and dorsal periaqueductal grey matter.

    PubMed

    de Oliveira, Ricardo; de Oliveira, Rithiele Cristina; Falconi-Sobrinho, Luiz Luciano; da Silva Soares, Raimundo; Coimbra, Norberto Cysne

    2017-01-01

    The electrical stimulation of the dorsolateral columns of the periaquedutal grey matter (dlPAG) or deep layers of the superior colliculus (dlSC) evokes defensive behaviours followed by an antinociceptive response. Monoaminergic brainstem reticular nuclei are suggested to comprise the endogenous pain modulatory system. The aim of the present work was to investigate the role played by 5-HT2 subfamily of serotonergic receptors of the nucleus raphe magnus (NRM) and the gigantocellularis/paragigantocellularis pars α reticular nuclei (Gi/PGiα) in the elaboration of instinctive fear-induced antinociception elicited by electrical stimulation of dlPAG or of dlSC. The nociceptive thresholds were measured by the tail-flick test in Wistar rats. The 5-HT2A/2C-serotonergic receptors antagonist ritanserin was microinjected at different concentrations (0.05, 0.5 and 5.0μg/0.2μL) either in Gi/PGiα or in NRM. The blockade of 5-HT2 receptors in both Gi/PGiα and NRM decreased the innate fear-induced antinociception elicited by electrical stimulation of the dlSC or the dlPAG. These findings indicate that serotonin is involved in the hypo-algesia induced by unconditioned fear-induced behavioural responses and the 5-HT2A/2C-serotonergic receptor subfamily in neurons situated in the Gi/PGiα complex and NRM are critically recruited in pain modulation during the panic-like emotional behaviour. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. The 5-hydroxytryptamine transporter is functional in human coronary artery smooth muscle cells proliferation and is regulated by Interleukin-1 beta

    PubMed Central

    Wang, Qing-Jie; Wang, Dong; Tang, Cheng-Chun

    2015-01-01

    Abnormal human coronary artery smooth muscle cells (hCASMCs) proliferation and migration are key factors in coronary artery restenosis after percutaneous coronary intervention. Platelets release 5-hydroxytryptamine (5-HT), which is a strong mitogen for pulmonary artery smooth muscle cells proliferation and migration. Here, we investigated the effects of 5-HT and role of 5-HT transporter (5-HTT) on hCASMCs proliferation and migration. The 5-HT (10-6-10-5 mol/l) significantly increased hCASMCs proliferation and migration, and these effects were inhibited by fluoxetine (10-5 mol/l) and citalopram (10-6 mol/l), two 5-HTT blocker. Overexpression in hCASMCs enhanced 5-HT induced cells proliferation and migration. The 5-HTT and interleukin-1 beta (IL-1β) expression were increased in rat balloon injury carotid arteries. Treatment with IL-1β (10 ng/ml, 3d) upregulates 5-HTT expression in hCASMCs and increased 5-HT induced currents in Human Embryonic Kidney 293-5-HTT cells. PMID:26221231

  13. Tong Xie Yao Fang relieves irritable bowel syndrome in rats via mechanisms involving regulation of 5-hydroxytryptamine and substance P.

    PubMed

    Yin, Yue; Zhong, Lei; Wang, Jian-Wei; Zhao, Xue-Ying; Zhao, Wen-Jing; Kuang, Hai-Xue

    2015-04-21

    To investigate whether the Chinese medicine Tong Xie Yao Fang (TXYF) improves dysfunction in an irritable bowel syndrome (IBS) rat model. Thirty baby rats for IBS modeling were separated from mother rats (1 h per day) from days 8 to 21, and the rectum was expanded by angioplasty from days 8 to 12. Ten normal rats were used as normal controls. We examined the effects of TXYF on defection frequency, colonic transit function and smooth muscle contraction, and the expression of 5-hydroxytryptamine (5-HT) and substance P (SP) in colonic and hypothalamus tissues by Western blot and RT-PCT techniques in both normal rats and IBS model rats with characterized visceral hypersensitivity. Defecation frequency was 1.8 ± 1.03 in normal rats and 4.5 ± 1.58 in IBS model rats (P < 0.001). However, the defecation frequency was significantly decreased (3.0 ± 1.25 vs 4.5 ± 1.58, P < 0.05), while the time (in seconds) of colon transit function was significantly increased (256.88 ± 20.32 vs 93.36 ± 17.28, P < 0.001) in IBS + TXYF group rats than in IBS group rats. Increased colonic smooth muscle tension and contract frequency in IBS model rats were significantly decreased by administration of TXYF. Exogenous agonist stimulants increased spontaneous activity and elicited contractions of colon smooth muscle in IBS model rats, and all of these actions were significantly reduced by TXYF involving 5-HT and SP down-regulation. TXYF can modulate the activity of the enteric nervous system and alter 5-HT and SP activities, which may contribute to the symptoms of IBS.

  14. Receptor reserve for 5-hydroxytryptamine1A-mediated inhibition of serotonin synthesis: possible relationship to anxiolytic properties of 5-hydroxytryptamine1A agonists.

    PubMed

    Meller, E; Goldstein, M; Bohmaker, K

    1990-02-01

    The irreversible receptor antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) was used to determine the relationship between receptor occupancy and response at central 5-hydroxytryptamine1A (5-HT1A) serotonin receptors mediating the inhibition of serotonin synthesis in rat cortex and hippocampus. Rats were treated with vehicle or EEDQ (2 or 6 mg/kg) and 24 hr later dose-response curves were constructed for inhibition of 5-hydroxytrytophan (5-HTP) accumulation (after decarboxylase inhibition with NSD-1015) by the selective 5-HT1A agonists 8-hydroxy-2(di-n-propylamino)tetralin (8-OH-DPAT) (0.01-3 mg/kg), buspirone (0.1-7.5 mg/kg), and ipsapirone (0.1-6.25 mg/kg) and the 5-HT1A agonist/antagonist BMY 7378 (0.015-5 mg/kg). In vehicle-pretreated rats, a similar maximal inhibition of 5-HT synthesis (range, 52-59%) was observed in both brain areas with 8-OH-DPAT, buspirone, and ipsapirone. These three agonists were also more potent in reducing 5-HTP accumulation in the cortex than in the hippocampus (ED50, 8-OH-DPAT, 14 and 30 microgram/kg; buspirone, 0.42 and 0.63 mg/kg; ipsapirone, 0.44 and 1.26 mg/kg, respectively). In the cortex, EEDQ treatment shifted the dose-response curves for 8-OH-DPAT, buspirone, and ipsapirone 8.6-, 2.0-, and 2.8-fold to the right, respectively. Corresponding rightward shifts in the hippocampus were smaller, 6.0-, 1.6-, and 2.1-fold, respectively. The EEDQ-induced shifts in the dose-response curves were accompanied by reductions in maximal response. In contrast, whereas the maximal inhibition of cortical 5-HTP accumulation by BMY 7378 (55%) was similar to that obtained with the agonists, maximal response in the hippocampus was much smaller (32%). Furthermore, in both brain regions EEDQ reduced the maximal response to BMY 7378 without shifting the dose-response curves. Analysis of the data by the double-reciprocal method of Furchgott, followed by calculation of fractional receptor occupancy for each dose of agonist, revealed a

  15. Potentiation of RSU-1069 tumour cytotoxicity by 5-hydroxytryptamine (5-HT).

    PubMed

    Chaplin, D J

    1986-11-01

    It is known that many solid animal tumours have a lower oxygenation level than most normal tissues and, in addition, that this level of oxygenation can be further decreased by systemic administration of 5-hydroxytryptamine (5-HT). The present study has investigated if such selective decrease in tumour oxygenation can be exploited by using the hypoxic cell cytotoxin, RSU-1069. The results obtained show that 5-HT at a dose of 5 mg kg-1, although not cytotoxic alone, can potentiate the cytotoxic effects of RSU-1069 in the Lewis lung carcinoma over the dose range 0.01-0.15 mg g-1. Maximum potentiation occurs when 5-HT is administered after RSU-1069. Potentiation of RSU-1069 cytotoxicity was observed using both the soft agar excision assay as an endpoint as well as in situ growth delay. In addition, the study shows that potentiation of RSU-1069 (0.1 mg g-1) cytotoxicity can be seen with 5-HT doses as low as 0.5 mg kg-1. In contrast to the tumour cytotoxicity results, 5-HT at a dose of 5 mg kg-1 i.p. did not affect the systemic toxicity, as measured by LD50/7d of RSU-1069. Thus, these results indicate that 5-HT can increase the therapeutic efficiency of RSU-1069. Such a finding is consistent with the rationale that selective reduction in tumour blood flow and oxygenation induced by 5-HT can be exploited using the hypoxic cell cytotoxin RSU-1069.

  16. Effect of halothane on metabolism of 5-hydroxytryptamine by rat lungs perfused in situ.

    PubMed Central

    Watkins, C A; Wartell, S A; Rannels, D E

    1983-01-01

    The effect of halothane (2-bromo-2-chloro-1,1,1-trifluoroethane) on the uptake of 14C-labelled 5-hydroxytryptamine (5-HT) and its metabolism to 5-hydroxyindol-3-ylacetic acid (5-HIAA) was investigated in rat lungs perfused in situ. The rate of accumulation of 14C-labelled 5-HIAA in the tissue, monitored as an index of 5-HT metabolism, was linear with time, displayed saturation kinetics and remained stable for at least 180 min of perfusion. Exposure of the lungs to halothane (4%) for 60 min reversibly reduced production of 5-HIAA through an increase in the apparent Km for metabolism of the amine from 1.45 to 3.52 microM (P less than 0.001); the anaesthetic had no effect on the Vmax. of the process. The magnitude of the inhibition increased with time of exposure to the anaesthetic. Halothane exposure did not alter the distribution of [3H]sorbitol or [14C]5-HT, pulmonary vascular resistance, levels of ATP or the kinetics of amino acid transport in the tissue. Inhibition of protein synthesis by cycloheximide did not mimic the effect of the anaesthetic. These observations, together with those made in lungs exposed to inhibitors of 5-HT uptake and metabolism, were consistent with a halothane-mediated inhibition of 5-HT uptake, which did not appear to involve non-specific changes in membrane permeability. PMID:6847641

  17. Role of 5-hydroxytryptamine in the regulation of brain neuropeptides in normal and diabetic rat

    NASA Technical Reports Server (NTRS)

    Kolta, Malak G.; Williams, Byron B.; Soliman, Karam F. A.

    1986-01-01

    The effect of 5-hydroxytryptamine (5-HT) alteration on brain dopamine (DA), norepinephrine (NE), beta-endorphin (beta-E), and immunoreactive insulin was studied in Sprague-Dawley diabetic and control rats. Diabetes was induced using alloxan (45 mg/kg), 15 days prior to sacrificing. Both control and diabetic animals were treated with either p-chlorophenylalanine (PCPA, 300 mg/kg) three days prior to sacrificing or fluoxetine (10 mg/kg) twice daily for three days. PCPA treatment significantly decreased brain content of 5-HT and 5-hydroxyindolel acetic acid, while it caused significant increase and decrease in brain beta-E and insulin levels, respectively, in both normal and diabetic rat. Meanwhile, the administration of fluoxetine resulted in significant increase in brain content of 5-HT, DA, NE and insulin but significant decline of beta-E in diabetic and saline control rats. The results of this experiment indicate that 5-HT may be regulating both beta-E and insulin regardless of the availability of pancreatic insulin.

  18. Allergic sensitization modifies the pulmonary expression of 5-hydroxytryptamine receptors in guinea pigs.

    PubMed

    Córdoba-Rodríguez, Guadalupe; Vargas, Mario H; Ruiz, Víctor; Carbajal, Verónica; Campos-Bedolla, Patricia; Mercadillo-Herrera, Paulina; Arreola-Ramírez, José Luis; Segura-Medina, Patricia

    2016-03-01

    There is mounting evidence that 5-hydroxytryptamine (5-HT) plays a role in asthma. However, scarce information exists about the pulmonary expression of 5-HT receptors and its modification after allergic sensitization. In the present work, we explored the expression of 5-HT1A, 5-HT2A, 5-HT3, 5-HT4, 5-ht5a, 5-HT6, and 5-HT7 receptors in lungs from control and sensitized guinea pigs through qPCR and Western blot. In control animals, mRNA from all receptors was detectable in lung homogenates, especially from 5-HT2A and 5-HT4 receptors. Sensitized animals had decreased mRNA expression of 5-HT2A and 5-HT4 receptors and increased that of 5-HT7 receptor. In contrast, they had increased protein expression of 5-HT2A receptor in bronchial epithelium and of 5-HT4 receptor in lung parenchyma. The degree of airway response to the allergic challenge was inversely correlated with mRNA expression of the 5-HT1A receptor. In summary, our results showed that major 5-HT receptor subtypes are constitutively expressed in the guinea pig lung, and that allergic sensitization modifies the expression of 5-HT2A, 5-HT4, and 5-HT7 receptors. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Species differences in the responses of pulmonary vascular preparations to 5-hydroxytryptamine.

    PubMed

    Morcillo, E J; Cortijo, J

    1999-01-01

    5-Hydroxytryptamine (5-HT) has been implicated in pulmonary hypertension, hypoxic pulmonary vasoconstriction, and the pulmonary side-effects of some drugs. 5-HT contracts bovine, ovine, canine, caprine, feline, rabbit, guinea-pig and rat isolated pulmonary arteries mainly by activation of 5-HT2A receptors but relaxes porcine pulmonary artery through activation of endothelial 5-HT2B receptors. Pharmacological responses of the pulmonary veins to 5-HT have been less studied and comprise both contraction (bovine, canine, feline, equine, rabbit) and relaxation (ovine, caprine). Functional and radioligand binding studies in human isolated intrapulmonary arteries and veins have demonstrated a mixed population of 5-HT1B/1D and 5-HT2A receptors mediating vasoconstriction but no evidence of involvement of 5-HT1A, 5-HT3 and 5-HT4 receptors. Remarkable differences exist in the in vitro pulmonary vasoreactivity to 5-HT and related drugs in humans compared with other mammals. Therefore, the use of human tissues is to be preferred to study pathophysiological responses of pulmonary circulation with clinical relevance.

  20. Methotrexate causes a change in intestinal 5-hydroxytryptamine metabolism in rats.

    PubMed

    Takano, Yuho; Machida, Takuji; Obara, Yusuke; Hirano, Megumi; Kudo, Sae; Takagi, Minako; Hamaue, Naoya; Iizuka, Kenji; Hirafuji, Masahiko

    2014-10-05

    The effects of methotrexate on 5-hydroxytryptamine (5-HT) metabolism in the intestinal tissue of rats were investigated during the delayed phase after a single administration. Rats were i.p. injected with methotrexate or with saline as a control, and kaolin and food intakes were measured by an automatic monitoring apparatus. At 96 h after administration, dissected-out ileal tissue was frozen rapidly in liquid nitrogen for further analysis or fixed for immunohistochemical staining. Methotrexate at a dose of 50 mg/kg caused a time-dependent increase in kaolin intake lasting up to 72 h after administration, which returned to the control level at 96 h after administration. This dose of methotrexate caused a gradual decrease in body weight, food intake, and water intake lasting up to 72 h, which approached the control level at 96 h. Methotrexate caused pathologic changes, including a moderate inflammatory response in the ileal tissue and an increase in the number of L-tryptophan hydroxylase (TPH)-expressing cells in the ileal mucosa. Methotrexate also caused a significant increase in 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) content and in TPH1 mRNA expression in the ileal tissues. It had no significant effects on mRNA expression of serotonin transporter, COX-1, or COX-2 or on myeloperoxidase activity. This study demonstrated, for the first time, that methotrexate caused a change in the ileal 5-HT metabolism associated with hyperplasia of mucosal enterochromaffin cells.

  1. Interactions between GABA and 5-hydroxytryptamine in the guinea-pig ileum.

    PubMed

    Ong, J; Kerr, D I

    1983-10-28

    In isolated segments of the guinea-pig ileum, there was: (a) an early, short-lived (less than 20 s) depression by gamma-aminobutyric acid (GABA) of contractile responses to 5-hydroxytryptamine (5-HT), acetylcholine(ACh), or nicotine, also seen with 3-amino-1-propanesulphonic acid (3APS) or muscimol in place of GABA, and sensitive to bicuculline, picrotoxinin or piretanide, and (b) a delayed, longer-lasting (30 s-1 min) depression of responses to 5-HT and nicotine, but not exogenously applied ACh, also seen with baclofen and only antagonised by delta-aminovaleric acid (DAVA). At 25 degrees C, all these effects were still observed but slowed, whilst at 37 degrees C after cold storage (6 degrees C) overnight, the early, short-lived depression was reduced or eliminated, yet the delayed depression was enhanced. It is concluded that the early, short-lived depression is mediated through GABAA-receptor sites, and the delayed, longer-lasting depression through GABAB-receptor sites on neurones of the myenteric plexus; effects consistent with GABA being a neurotransmitter in the enteric nervous system.

  2. Effects of 5-hydroxytryptamine on defecation in open-field behavior in rats.

    PubMed

    Kameyama, T; Suzuki, M; Nabeshima, T

    1980-06-01

    An attempt was made to elucidate the role of the serotonergic nervous sytem in defecation resulting from environmental stimulation in rats. The open-field (OF) test and shuttle box method were used to study the defecation. 5-Hydroxytryptophan (5-HTP) significantly decreased the number of fecal boluses excreted in both emotional situations, namely, in both OF and shuttle box. The fecal excretion was significantly reduced compared with the controls after intraventricular injection of 5-hydroxytryptamine (5-HT). Animals pretreated with p-chlorophenylalanine (pCPA) and 5,6-dihydroxytryptamine (5,6-DHT) tended to show a slight increase in the OF defecation. 5-HTP was equally effective in diminishing the OF performance of pCPA-treated rats. The inhibitory effects of 5-HTP on the defecation were also observed after depletion of biogenic amines by reserpine treatment. Home cage defecation was increased after 5-HTP administration, decreased under pretreatment with pCPA and not influenced by intraventricular injection of 5-HTP. These results suggested that the defecation after environmental stimuli was due to a change in 5-HT levels in the brain.

  3. 5-hydroxytryptamine1B receptor and triptan response in migraine, lack of association with common polymorphisms.

    PubMed

    Velati, Daniela; Viana, Michele; Cresta, Stefania; Mantegazza, Paola; Testa, Lucia; Bettucci, Diego; Rinaldi, Maurizio; Sances, Grazia; Tassorelli, Cristina; Nappi, Giuseppe; Canonico, Pier Luigi; Martignoni, Emilia; Genazzani, Armando A

    2008-02-02

    Triptans mediate vasoconstriction of meningeal vessels via stimulation of vascular 5-hydroxytryptamine (5-HT)(1B) receptors. These drugs are recommended for acute treatment in patients with moderate-to-severe migraine attacks and in those patients with mild-to-moderate headache that are not controlled adequately by other agents. Yet, approximately 25% of all migraine users and 40% of all attacks do not respond to triptan treatment. Among the hypothesis to explain this is the possibility that genetic single nucleotide polymorphisms that alter the receptor, for example changing the transcriptional rate and therefore the amount of target protein might change the clinical response to these drugs. In the present contribution, we therefore decided to evaluate whether single nucleotide polymorphisms on the 5-HT(1B) gene might contribute to inter-individual variability in clinical responses to triptans. Two polymorphisms in the promoter region of the 5-HT(1B) receptor (T-261G and A-161T) and the synonymous variation G861C in the coding region were genotyped by restriction fragment length polymorphism in 105 migraine patients. In our sample population, 71% of patients responded to triptans. Allelic and diplotype frequencies were not significantly different between responders and non-responders. On the other hand, extrapolation of in vitro data on promoter activity would suggest that patients with higher copy number of receptors respond slightly better. Our data therefore do not support the involvement of 5-HT(1B) single nucleotide polymorphisms in mediating the inter-individual variability to triptans.

  4. γ-Aminobutyric acid suppresses enhancement of hamster sperm hyperactivation by 5-hydroxytryptamine

    PubMed Central

    FUJINOKI, Masakatsu; TAKEI, Gen L.

    2016-01-01

    Sperm hyperactivation is regulated by hormones present in the oviduct. In hamsters, 5-hydroxytryptamine (5HT) enhances hyperactivation associated with the 5HT2 receptor and 5HT4 receptor, while 17β-estradiol (E2) and γ-aminobutyric acid (GABA) suppress the association of the estrogen receptor and GABAA receptor, respectively. In the present study, we examined the regulatory interactions among 5HT, GABA, and E2 in the regulation of hamster sperm hyperactivation. When sperm were exposed to E2 prior to 5HT exposure, E2 did not affect 5HT-enhanced hyperactivation. In contrast, GABA partially suppressed 5HT-enhanced hyperactivation when sperm were exposed to GABA prior to 5HT. GABA suppressed 5HT-enhanced hyperactivation associated with the 5HT2 receptor although it did not suppress 5HT-enhanced hyperactivation associated with the 5HT4 receptor. These results demonstrate that hamster sperm hyperactivation is regulated by an interaction between the 5HT2 receptor-mediated action of 5HT and GABA. PMID:27773888

  5. Radioimmunoassay of serotonin (5-hydroxytryptamine) in cerebrospinal fluid, plasma, and serum

    SciTech Connect

    Engbaek, F.; Voldby, B

    1982-04-01

    A direct radioimmunoassay is described for serotonin (5-hydroxytryptamine) in cerebrospinal fluid, platelet-poor plasma, and serum. Antisera in rabbits was raised against serotonin diazotized to a conjugate of bovine albumin and D,L-p-aminophenylalanine. Polyethylene glycol, alone or in combination with anti-rabbit immunoglobulins, is used to separate bound and unbound tritiated serotonin. The minimum concentration of serotonin detectable is 2 nmol/L in a 200-..mu..L sample. Within-day precision (CV) is 4.3% between-day precision 7.7%. Analytical recoveries of serotonin are 109% and 101% for cerebrospinal fluid and plasma, respectively. Tryptophan, 5-hydroxytryptophan, 5-hydroxyindoleacetic acid, and 5-hydroxytryptophol do not interfere with the assay. However, 5-methoxytryptamine and tryptamine cross react. Of samples of cerebrospinal fluid from patients with disc herniations (n=21) or low-pressure hydrocephalus (n=10), one-third had concentrations of 2-4 nmol/L and two-thirds were below the minimum detectable concentration. The observed range for the concentration of serotonin in plasma of 14 normal subjects was 5-14 nmol/L (mean +/- SD, 9 +/- 3 nmol/L). The observed ranges for serotonin in serum were: for 10 women 520-900 (mean +/- SD: 695 +/- 110) nmol/L and for 10 men 380-680 (520 +/- 94) nmol/L.

  6. beta-Adrenoceptor agonists enhance 5-hydroxytryptamine-mediated behavioural responses.

    PubMed Central

    Cowen, P. J.; Grahame-Smith, D. G.; Green, A. R.; Heal, D. J.

    1982-01-01

    The beta-adrenoceptor agonists, salbutamol, terbutaline and clenbuterol, were investigated for their effect on 5-hydroxytryptamine-mediated (5-HT) hyperactivity. 2 The lipophilic beta-adrenoceptor agonist, clenbuterol (5 mg/kg) enhanced the behaviours induced by quipazine (25 mg/kg), including headweaving, forepaw treading and hind-limb abduction and thus increased automated activity recording. Clenbuterol (5 mg/kg) also enhanced the hyperactivity syndrome produced by the 5-HT agonist, 5-methoxy N,N-dimethyltryptamine (2 mg/kg) and the combination of tranylcypromine (10 mg/kg) and L-tryptophan (50 mg/kg). Salbutamol and terbutaline potentiated quipazine-induced hyperactivity only when given at the higher dose of 20 mg/kg. 3 The effect of clenbuterol in enhancing quipazine hyperactivity was blocked by the centrally acting beta 1-adrenoceptor antagonist, metoprolol (5 mg/kg), but not by the beta 2-adrenoceptor antagonist, butoxamine (5 mg/kg) or the peripherally acting beta 1-adrenoceptor antagonist, atenolol (5 mg/kg). 4 Clenbuterol (5 mg/kg) did not enhance the circling responses produced by methamphetamine (0.5 mg/kg) in unilateral nigrostriatal-lesioned rats. 5 The results suggest that beta-adrenoceptor agonists in common with some established antidepressant treatments produce enhancement of 5-HT-mediated behavioural responses. PMID:6124294

  7. Portal veins of mice infected with Schistosoma mansoni exhibit an increased reactivity to 5-hydroxytryptamine.

    PubMed

    Silva, C L; Morel, N; Noël, F

    1998-01-01

    In chronic severe infection with Schistosoma mansoni, portal hypertension and related vascular alterations usually develop as a consequence of granulomatous response to eggs. In order to investigate a putative direct effect of worms on the reactivity of their host portal vein, mice infected only with male worms were used in the present study. An higher reactivity to 5-hydroxytryptamine (5-HT) characterized by an increase in the maximal contraction and sensitivity was observed in portal vein from infected mice compared to healthy mice. Blockade of NO-synthase with l-NAME induced a small increase in 5-HT potency in portal vein from non-infected mice without changing the amplitude of the contractions, whereas it did not alter the reactivity of veins from infected mice. The present results show that unisexual infection of mice with male S. mansoni increased the reactivity of the portal vein to 5-HT which seems to be partially related to an alteration in the nitric oxide release by endothelium.

  8. Increased reactivity to 5-hydroxytryptamine of portal veins from mice infected with Schistosoma mansoni.

    PubMed

    Silva, C L; Morel, N; Lenzi, H L; Noël, F

    1998-07-01

    In chronic severe infection with Schistosoma mansoni, portal hypertension accompanied by anatomical changes of the portal vasculature can develop as a consequence of granulomatous response to eggs. Mice infected unisexually with male worms were used in the present study in order to investigate a direct effect of worms on the reactivity of their host portal vein. A higher reactivity in the presence of 5-hydroxytryptamine (5-HT), but not in the presence of KCl 100 mM solution, was observed in portal vein from infected mice compared to healthy mice. It was characterized by an increase in the maximal contraction and sensitivity to 5-HT. Blockade of NO-synthase with N omega-nitro-L-arginine methyl ester (L-NAME) induced a small increase in 5-HT potency in the portal vein from non-infected mice, but did not change the amplitude of the contractions. In portal veins from infected mice, preincubation with L-NAME did not affect the reactivity to 5-HT. Histological analysis indicated endothelial damage, subendothelial fibrous plaques, and focal areas of inflammatory infiltrates in the adventitial layer. As a conclusion, these results show that unisexual infection of mice with male S. mansoni increased the reactivity of the portal vein to 5-HT which seems to be only partially related to an alteration in the endothelial production of nitric oxide.

  9. Kinetic characterization of 5-hydroxytryptamine receptor desensitization in isolated guinea-pig trachea and rabbit aorta.

    PubMed

    Ben-Harari, R R; Dalton, B A; Osman, R; Maayani, S

    1991-04-01

    Desensitization of the contractile response mediated by the 5-hydroxytryptamine2 (5-HT2) receptor in the isolated guinea-pig trachea and rabbit aorta is a time-dependent process and therefore it has been characterized by an apparent rate constant obtained from a kinetic analysis. Under similar conditions, desensitization of the response in the trachea is 7-fold faster than in the aorta. Desensitization is homologous and reversible and is not affected by inhibition of neuronal and extraneuronal uptake, monoamine oxidase activity, alpha 1 adrenergic, cholinergic muscarinic or histamine H1 receptors. Desensitization does not depend on removal of epithelium from the trachea or endothelium and adventitia from the aorta or on the release of a stable relaxant factor. It is also not affected by the removal of extracellular Ca++, which is needed for tonic contraction. The dependence of desensitization on agonist concentration, number of receptors and the intrinsic activity of the agonist was determined. The observed values of the rate constants for desensitization and of the peak tension (T peak) in trachea show a saturable dependence on the concentration of 5-HT, indicating that occupancy of the 5-HT2 receptor is needed for desensitization. The less efficacious agonists, N-methyl serotonin, dimethyltryptamine, quipazine, 5-methoxytryptamine, 5-methyltryptamine, 5-methoxy dimethyltryptamine, 4-hydroxytryptamine and bufotenine induce significantly slower desensitization than 5-HT. A 25 to 75% reduction in 5-HT2 receptor number by alkylation had no effect on the observed rate constants for desensitization.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Selective 5-hydroxytryptamine2 receptor antagonists protect against the neurotoxicity of methylenedioxymethamphetamine in rats.

    PubMed

    Schmidt, C J; Abbate, G M; Black, C K; Taylor, V L

    1990-11-01

    The serotonergic deficits resulting from methylenedioxymethamphetamine (MDMA)-induced neurotoxicity were prevented by the simultaneous administration of 5-hydroxytryptamine2 (5-HT2) receptor antagonists such as MDL 11,939 or ritanserin. This effect was not region specific as protection was observed in the cortex, hippocampus and striatum 1 week after the administration of a single dose of MDMA. MDL 11,939 also showed some efficacy at reducing the deficits in 5-HT concentrations and tryptophan hydroxylase activity produced by multiple administrations of MDMA. Protection against the neurotoxicity required the administration of MDL 11,939 within 1 hr of MDMA indicating 5-HT2 receptor activation was an early event in the process leading to terminal damage. Examination of the effect of the 5-HT2 receptor blockade on the early neurochemical alterations induced by MDMA revealed an inhibitory effect on MDMA-stimulated dopamine synthesis. Analysis of these data and the associated changes in dopamine metabolites indicates that 5-HT2 receptor antagonists block MDMA-induced neurotoxicity by interfering with the ability of the dopamine neuron to maintain its cytoplasmic pool of transmitter and thereby sustain carrier-mediated dopamine release.

  11. Photoaffinity labeling of the 5-hydroxytryptamine 1A receptor in rat hippocampus.

    PubMed

    Ransom, R W; Asarch, K B; Shih, J C

    1986-10-01

    1-[2-(4-Azidophenyl)ethyl]-4-(3-trifluoromethylphenyl)piperazine (p-azido-PAPP) inhibits [3H]5-hydroxytryptamine [( 3H]5-HT) binding to 5-HT1A and 5-HT1B sites in rat brain with equilibrium dissociation constants (KD) of 0.9 nM and 230 nM, respectively. [3H]p-Azido-PAPP was synthesized and its reversible and irreversible binding properties to the hippocampal 5-HT1A site characterized. [3H]p-Azido-PAPP labeled a single class of sites in rat hippocampal membranes with a KD of 1 nM and a maximal binding density of 370 fmol/mg protein. The pharmacological profile of [3H]p-azido-PAPP binding was consistent with the radioligand's selective interaction with the 5-HT1A receptor. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of membranes preincubated with [3H]p-azido-PAPP and irradiated showed a major band of incorporation of radioactivity at approximately 55,000 daltons. This incorporation could be blocked when membranes were incubated with 1 microM of several agents that have high affinity for 5-HT1A sites [5-HT, 8-hydroxy-2-(di-n-propylamino)tetraline, TVX Q 7821, spiperone, buspirone, d-lysergic acid diethylamide, metergoline]. The results indicate that on photolysis [3H]p-azido-PAPP irreversibly labels a polypeptide that is, or is a subunit of, the 5-HT1A receptor in rat hippocampus.

  12. Skimmianine and related furoquinolines function as antagonists of 5-hydroxytryptamine receptors in animals.

    PubMed

    Cheng, J T; Chang, T K; Chen, I S

    1994-10-01

    1. Skimmianine, kokusaginine and confusameline, three furoquinolines extracted from the leaves of Evodia merrillii (Rutaceae), were investigated to characterize their selective effects on subtypes of 5-hydroxytryptamine (5-HT) receptors. 2. In the isolated membranes of rat cerebrocortex, using [3H]-5-HT and [3H]-ketanserin as radioligands, skimmianine and the two other furoquinolines displaced radioligand bindings in a concentration-dependent manner. Lower concentrations were required to affect [3H]-ketanserin binding than [3H]-5-HT binding in the order skimmianine > kokusaginine > confusameline. 3. Furoquinolines inhibited 5-HT-induced contraction mediated by 5-HT2 receptors in the presence of methiothepin in rat isolated aorta. Also, the combination of furoquinolines with ketanserin showed an additive antagonism. 4. These furoquinolines were inactive on the 5-carboxamidotryptamine-induced relaxation of guinea-pig ileum, a 5-HT1-mediated event. However, 5-HT-induced contraction via 5-HT2 receptors was reduced by these furoquinolines in a way similar to that in blood vessels. 5. The failure of these compounds to affect the 5-HT-induced Bezold-Jarisch-like reflex in anaesthetized rats, the major 5-HT3-mediated action, ruled out an action on 5-HT3 receptors. 6. The results obtained suggest that three furoquinoline alkaloids may act on 5-HT receptors in animals, more selectively to the 5-HT2 subtype, in the order of skimmianine > kokusaginine > confusameline.

  13. Influence of AMPA/kainate receptors on extracellular 5-hydroxytryptamine in rat midbrain raphe and forebrain

    PubMed Central

    Tao, Rui; Ma, Zhiyuan; Auerbach, Sidney B

    1997-01-01

    The regulation of 5-hydroxytryptamine (5-HT) release by excitatory amino acid (EAA) receptors was examined by use of microdialysis in the CNS of freely behaving rats. Extracellular 5-HT was measured in the dorsal raphe nucleus (DRN), median raphe nucleus (MRN), nucleus accumbens, hypothalamus, frontal cortex, dorsal and ventral hippocampus. Local infusion of kainate produced increases in extracellular 5-HT in the DRN and MRN. Kainate infusion into forebrain sites had a less potent effect. In further studies of the DRN and nucleus accumbens, kainate-induced increases in extracellular 5-HT were blocked by the EAA receptor antagonists, kynurenate and 6,7-dinitroquinoxaline-2,3-dione (DNQX). The effect of infusing kainate into the DRN or nucleus accumbens was attenuated or abolished by tetrodotoxin (TTX), suggesting that the increase in extracellular 5-HT is dependent on 5-HT neuronal activity. In contrast, ibotenate-induced lesion of intrinsic neurones did not attenuate the effect of infusing kainate into the nucleus accumbens. Thus, the effect of kainate in the nucleus accumbens does not depend on intrinsic neurones. Infusion of α-amino-3-hydroxy-5-methyl-4-isoxazolaproprionate (AMPA) into the DRN and nucleus accumbens induced nonsignificant changes in extracellular 5-HT. Cyclothiazide and diazoxide, which attenuate receptor desensitization, greatly enhanced the effect of AMPA on 5-HT in the DRN, but not in the nucleus accumbens. In conclusion, AMPA/kainate receptors regulate 5-HT in the raphe and in forebrain sites. PMID:9283707

  14. Importance of phenylalanine 107 in agonist recognition by the 5-hydroxytryptamine(3A) receptor.

    PubMed

    Steward, L J; Boess, F G; Steele, J A; Liu, D; Wong, N; Martin, I L

    2000-06-01

    The 5-hydroxytryptamine (5-HT)(3) receptor is a member of the ligand-gated ion channel receptor family with significant homology to the nicotinic acetylcholine, gamma-aminobutyric acid(A), and glycine receptors. In this receptor class, the agonist binding site is formed by parts of the extracellular amino-terminal region. This study examines the effects of altering phenylalanine 107 (F107) of the 5-HT(3AL) subunit, obtained from NG108-15 cells, using site-directed mutagenesis. The wild-type (WT) and mutant receptors were expressed in HEK 293 cells and characterized using both whole-cell patch-clamp and radioligand binding. The tyrosine mutant F107Y exhibits a significantly lower affinity for the agonist 5-HT (K(i) = 203 versus 15.6 nM) and an increase of similar magnitude in the EC(50) value (10.6 versus 1.2 microM) compared with WT. The activation kinetics of the maximal currents generated by 5-HT with this mutant were markedly slower than those of the WT receptor, but application of supramaximal concentrations of the agonist markedly decreased the time to half-peak. The asparagine mutant F107N displayed a significantly higher affinity for 5-HT than the WT receptor (1.62 versus 15.6 nM), which was mirrored in direction and magnitude by changes in the EC(50) value for this agonist (0.2 versus 1.2 microM). In contrast to the WT receptor, the mutant F107N was activated by acetylcholine (EC(50) = 260 microM). The response to acetylcholine was blocked by the 5-HT(3) receptor antagonist renzapride with a similar IC(50) value as that determined against currents generated by 5-HT in the WT receptor. These data suggest that F107 is an important determinant of agonist recognition at the 5-HT(3) receptor.

  15. Potentiation of RSU-1069 tumour cytotoxicity by 5-hydroxytryptamine (5-HT).

    PubMed Central

    Chaplin, D. J.

    1986-01-01

    It is known that many solid animal tumours have a lower oxygenation level than most normal tissues and, in addition, that this level of oxygenation can be further decreased by systemic administration of 5-hydroxytryptamine (5-HT). The present study has investigated if such selective decrease in tumour oxygenation can be exploited by using the hypoxic cell cytotoxin, RSU-1069. The results obtained show that 5-HT at a dose of 5 mg kg-1, although not cytotoxic alone, can potentiate the cytotoxic effects of RSU-1069 in the Lewis lung carcinoma over the dose range 0.01-0.15 mg g-1. Maximum potentiation occurs when 5-HT is administered after RSU-1069. Potentiation of RSU-1069 cytotoxicity was observed using both the soft agar excision assay as an endpoint as well as in situ growth delay. In addition, the study shows that potentiation of RSU-1069 (0.1 mg g-1) cytotoxicity can be seen with 5-HT doses as low as 0.5 mg kg-1. In contrast to the tumour cytotoxicity results, 5-HT at a dose of 5 mg kg-1 i.p. did not affect the systemic toxicity, as measured by LD50/7d of RSU-1069. Thus, these results indicate that 5-HT can increase the therapeutic efficiency of RSU-1069. Such a finding is consistent with the rationale that selective reduction in tumour blood flow and oxygenation induced by 5-HT can be exploited using the hypoxic cell cytotoxin RSU-1069. PMID:3801269

  16. Peptide YY3–36 and 5-Hydroxytryptamine Mediate Emesis Induction by Trichothecene Deoxynivalenol (Vomitoxin)

    PubMed Central

    Pestka, James J.

    2013-01-01

    Deoxynivalenol (DON, vomitoxin), a trichothecene mycotoxin produced by Fusarium sp. that frequently occurs in cereal grains, has been associated with human and animal food poisoning. Although a common hallmark of DON-induced toxicity is the rapid onset of emesis, the mechanisms for this adverse effect are not fully understood. Recently, our laboratory has demonstrated that the mink (Neovison vison) is a suitable small animal model for investigating trichothecene-induced emesis. The goal of this study was to use this model to determine the roles of two gut satiety hormones, peptide YY3–36 (PYY3–36) and cholecystokinin (CCK), and the neurotransmitter 5-hydroxytryptamine (5-HT) in DON-induced emesis. Following ip exposure to DON at 0.1 and 0.25mg/kg bw, emesis induction ensued within 15–30min and then persisted up to 120min. Plasma DON measurement revealed that this emesis period correlated with the rapid distribution and clearance of the toxin. Significant elevations in both plasma PYY3–36 (30–60min) and 5-HT (60min) but not CCK were observed during emesis. Pretreatment with the neuropeptide Y2 receptor antagonist JNJ-31020028 attenuated DON- and PYY-induced emesis, whereas the CCK1 receptor antagonist devezapide did not alter DON’s emetic effects. The 5-HT3 receptor antagonist granisetron completely suppressed induction of vomiting by DON and the 5-HT inducer cisplatin. Granisetron pretreatment also partially blocked PYY3–36-induced emesis, suggesting a potential upstream role for this gut satiety hormone in 5-HT release. Taken together, the results suggest that both PYY3–36 and 5-HT play contributory roles in DON-induced emesis. PMID:23457120

  17. Peptide displacement of ( sup 3 H)5-hydroxytryptamine binding to bovine cortical membranes

    SciTech Connect

    Takeuchi, Y.; Root-Bernstein, R.S.; Shih, J.C. )

    1990-12-01

    Chemical studies have demonstrated that peptides such as the encephalitogenic (EAE) peptide of myelin basic protein (MBP) and luteinizing hormone-releasing hormone (LHRH) can bind serotonin (5-hydroxytryptamine, 5-HT) in vitro. The present research was undertaken to determine whether such binding interferes with 5-HT binding to its 5-HT1 receptors on bovine cerebral cortical membranes. EAE peptide and LHRH displaced ({sup 3}H)5-HT with IC50s of 4.0 x 10(-4) and 1.8 x 10(-3) M respectively. MBP itself also showed apparent displacing ability with an IC50 of 6.0 x 10(-5) M, though it also caused aggregation of cortical membranes that might have interfered with normal receptor binding. These results support previous suggestions that the tryptophan peptide region of MBP may act as a 5-HT receptor in the neural system. We also tested the effects of muramyl dipeptide (N-acetyl-muramyl-L-Ala-D-isoGln, MD), a bacterial cell-wall breakdown product that acts as a slow-wave sleep promoter, binds to LHRH and EAE peptide, and competes for 5-HT binding sites on macrophages. It showed no significant displacement of 5-HT binding to cortical membranes (IC50 greater than 10(-1) M), but its D-Ala analogue did (IC50 = 1.7 x 10(-3) M). Thus, it seems likely that the 5-HT-related effects of naturally occurring muramyl peptides are physiologically limited by receptor types.

  18. Antidepressant drugs inhibit a glial 5-hydroxytryptamine transporter in rat brain.

    PubMed

    Bal, N; Figueras, G; Vilaró, M T; Suñol, C; Artigas, F

    1997-08-01

    We assessed the role of glial cells in the uptake of serotonin (5-hydroxytryptamine, 5-HT). Primary cultures of rat and mouse cortical astrocytes took up and deaminated 5-HT. The antidepressants citalopram, clomipramine, fluoxetine, fluvoxamine, paroxetine and sertraline inhibited this process. The presence of the mRNAs for the 5-HT transporter and monoamine oxidase-A (MOA-A) was established in cultured astrocytes and in adult rat brain areas with (midbrain and brainstem) and without (frontal cortex) serotonergic cell bodies after reverse transcription-polymerase chain reaction and hybridization with probes complementary to the cloned neuronal 5-HT transporter and MAO-A. To examine in vivo the role of astrocytes in the elimination of 5-HT from the extracellular brain space, 5-HT was perfused through dialysis probes implanted in the frontal cortex of conscious rats and its concentration was measured at the probe outlet. Tissue 5-HT recovery was dose-dependently inhibited by the concurrent perfusion of citalopram, fluoxetine and paroxetine, showing that it essentially measured uptake through the high-affinity 5-HT transporter. Rats lesioned with 5,7-dihydroxytryptamine (5,7-DHT; 88% reduction of tissue 5-HT) displayed tissue 5-HT recovery slightly higher than sham-operated rats (55 +/- 2 vs. 46 +/- 3%, P < 0.001), a finding perhaps attributable to the astrogliosis induced by 5,7-DHT denervation. Rats lesioned with 6-hydroxydopamine showed tissue 5-HT uptake similar to controls, suggesting negligible reuptake of 5-HT by catecholaminergic terminals. These results are consistent with the presence of a glial component of 5-HT uptake in the rodent brain, sensitive to antidepressants, which takes place through a 5-HT transporter very similar or identical to that present in neurons.

  19. 5-Hydroxytryptamine does not reduce sympathetic nerve activity or neuroeffector function in the splanchnic circulation

    PubMed Central

    Darios, Emma S.; Barman, Susan M.; Orer, Hakan S.; Morrison, Shaun F.; Davis, Robert P.; Seitz, Bridget M.; Burnett, Robert; Watts, Stephanie W.

    2015-01-01

    Infusion of 5-hydroxytryptamine (5-HT) in conscious rats results in a sustained (up to 30 days) fall in blood pressure. This is accompanied by an increase in splanchnic blood flow. Because the splanchnic circulation is regulated by the sympathetic nervous system, we hypothesized that 5-HT would: 1) directly reduce sympathetic nerve activity in the splanchnic region; and/or 2) inhibit sympathetic neuroeffector function in splanchnic blood vessels. Moreover, removal of the sympathetic innervation of the splanchnic circulation (celiac ganglionectomy) would reduce 5-HT-induced hypotension. In anaesthetized Sprague-Dawley rats, mean blood pressure was reduced from 101 ± 4 to 63 ± 3 mm Hg during slow infusion of 5-HT (25 μg/kg/min, i.v.). Pre- and postganglionic splanchnic sympathetic nerve activity was unaffected during 5-HT infusion. In superior mesenteric arterial rings prepared for electrical field stimulation, neither 5-HT (3, 10, 30 nM), the 5-HT1B receptor agonist CP 93129 nor 5-HT1/7 receptor agonist 5-carboxamidotryptamine inhibited neurogenic contraction compared to vehicle. 5-HT did not inhibit neurogenic contraction in superior mesenteric venous rings. Finally, celiac ganglionectomy did not modify the magnitude of fall or time course of 5-HT-induced hypotension when compared to animals receiving sham ganglionectomy. We conclude it is unlikely 5-HT interacts with the sympathetic nervous system at the level of the splanchnic preganglionic or postganglionic nerve, as well as at the neuroeffector junction, to reduce blood pressure. These important studies allow us to rule out a direct interaction of 5-HT with the splanchnic sympathetic nervous system as a cause of the 5-HT-induced fall in blood pressure. PMID:25732865

  20. An electrophysiological study of 5-hydroxytryptamine receptors of neurones in the molluscan nervous system

    PubMed Central

    Gerschenfeld, H. M.; Stefani, E.

    1966-01-01

    1. 5-Hydroxytryptamine (5-HT) has been iontophoretically applied to the membrane of central neurones of Cryptomphallus aspersa; CILDA neurones (cells with inhibition of long duration) (Gerschenfeld & Tauc, 1964) are the only cells sensitive to 5-HT. The responses to 5-HT is always a depolarization. The CILDA cells studied were also depolarized by ACh. 2. From experiments in which pulses of 5-HT and ACh were applied from a double-barrelled micropipette to the CILDA cell soma, it has been calculated that 5-HT and ACh receptors were located at different distances from the injecting micropipette tip. It has also been calculated from the diffusion equation that in the same CILDA cell a 5-HT concentration of 8·2 × 10-9 M and a ACh concentration of 1·3 × 10-8 M caused a similar peak depolarization. 3. CILDA neurones show `anomalous' rectification. 5-HT increases the membrane conductance of CILDA. 4. 5-HT receptors of CILDA neurone are desensitized by repeated application of 5-HT. The desensitization lasts for ca. 40 sec. 5. 5-HT receptors are blocked by lysergic acid diethylamide and its derivatives. Morphine chlorhydrate blocks them non-competitively. 6. Some inhibitors of monoamine oxidase (trancylpromine, isocarboxazide, iproniazide and nialamide) have been tested. They do not prolong the action of 5-HT, but block the 5-HT receptors. 7. No crossed desensitization between 5-HT and ACh has been observed. Atropine blocks both ACh-receptors and 5-HT receptors, 5-HT receptors appear to be blocked to a greater extent. 8. The data presented support the assumption of a excitatory transmitter role of 5-HT to CILDA neurones, but further evidence is necessary to confirm this hypothesis. PMID:5918062

  1. Nelotanserin, a novel selective human 5-hydroxytryptamine2A inverse agonist for the treatment of insomnia.

    PubMed

    Al-Shamma, Hussien A; Anderson, Christen; Chuang, Emil; Luthringer, Remy; Grottick, Andrew J; Hauser, Erin; Morgan, Michael; Shanahan, William; Teegarden, Bradley R; Thomsen, William J; Behan, Dominic

    2010-01-01

    5-Hydroxytryptamine (5-HT)(2A) receptor inverse agonists are promising therapeutic agents for the treatment of sleep maintenance insomnias. Among these agents is nelotanserin, a potent, selective 5-HT(2A) inverse agonist. Both radioligand binding and functional inositol phosphate accumulation assays suggest that nelotanserin has low nanomolar potency on the 5-HT(2A) receptor with at least 30- and 5000-fold selectivity compared with 5-HT(2C) and 5-HT(2B) receptors, respectively. Nelotanserin dosed orally prevented (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI; 5-HT(2A) agonist)-induced hypolocomotion, increased sleep consolidation, and increased total nonrapid eye movement sleep time and deep sleep, the latter marked by increases in electroencephalogram (EEG) delta power. These effects on rat sleep were maintained after repeated subchronic dosing. In healthy human volunteers, nelotanserin was rapidly absorbed after oral administration and achieved maximum concentrations 1 h later. EEG effects occurred within 2 to 4 h after dosing, and were consistent with vigilance-lowering. A dose response of nelotanserin was assessed in a postnap insomnia model in healthy subjects. All doses (up to 40 mg) of nelotanserin significantly improved measures of sleep consolidation, including decreases in the number of stage shifts, number of awakenings after sleep onset, microarousal index, and number of sleep bouts, concomitant with increases in sleep bout duration. Nelotanserin did not affect total sleep time, or sleep onset latency. Furthermore, subjective pharmacodynamic effects observed the morning after dosing were minimal and had no functional consequences on psychomotor skills or memory. These studies point to an efficacy and safety profile for nelotanserin that might be ideally suited for the treatment of sleep maintenance insomnias.

  2. The effect of fasting on 5-hydroxytryptamine metabolism in brain regions of the albino rat.

    PubMed Central

    Fuenmayor, L. D.; García, S.

    1984-01-01

    The turnover of 5-hydroxytryptamine (5-HT) in the whole brain and different brain regions was studied in rats fasted for 24 h. These rats showed an increased tissue concentration of the amine in the whole brain and of its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the whole brain, the striatum, the combined pons-medulla and the cerebral cortex. The accumulation of 5-HIAA after probenecid was increased by fasting in the regions mentioned above except for the striatum. The effect of probenecid was also increased by fasting in the midbrain, the hypothalamus and the hippocampus. In the striatum, the administration of probenecid produced a smaller increase in 5-HIAA concentration in fasted than in fed rats. The decay of 5-HT following p-chlorophenylalanine (PCPA) was increased in the hypothalamus of fasted rats at 16 h, but not at 4 h, after the intraperitoneal administration of the inhibitor. In the midbrain, the striatum and the combined pons-medulla, food deprivation did not modify the decrease induced by PCPA. However, the inhibitor induced a reduction of food consumption in the fed group, which made this group rather similar to the fasted one and complicated the interpretation of the results in these last three cerebral areas. Our results confirm that food deprivation increases the turnover of brain 5-HT and point out that the increase probably occurs in all brain areas. This increased turnover appears to be accompanied, in the hypothalamus, by an increased neuronal release of the amine. In the striatum, fasting probably blocks the active transport system which removes acid metabolites from the brain. PMID:6207885

  3. 5-Hydroxytryptamine does not reduce sympathetic nerve activity or neuroeffector function in the splanchnic circulation.

    PubMed

    Darios, Emma S; Barman, Susan M; Orer, Hakan S; Morrison, Shaun F; Davis, Robert P; Seitz, Bridget M; Burnett, Robert; Watts, Stephanie W

    2015-05-05

    Infusion of 5-hydroxytryptamine (5-HT) in conscious rats results in a sustained (up to 30 days) fall in blood pressure. This is accompanied by an increase in splanchnic blood flow. Because the splanchnic circulation is regulated by the sympathetic nervous system, we hypothesized that 5-HT would: 1) directly reduce sympathetic nerve activity in the splanchnic region; and/or 2) inhibit sympathetic neuroeffector function in splanchnic blood vessels. Moreover, removal of the sympathetic innervation of the splanchnic circulation (celiac ganglionectomy) would reduce 5-HT-induced hypotension. In anaesthetized Sprague-Dawley rats, mean blood pressure was reduced from 101±4 to 63±3mm Hg during slow infusion of 5-HT (25μg/kg/min, i.v.). Pre- and postganglionic splanchnic sympathetic nerve activity were unaffected during 5-HT infusion. In superior mesenteric arterial rings prepared for electrical field stimulation, neither 5-HT (3, 10, 30nM), the 5-HT1B receptor agonist CP 93129 nor 5-HT1/7 receptor agonist 5-carboxamidotryptamine inhibited neurogenic contraction compared to vehicle. 5-HT did not inhibit neurogenic contraction in superior mesenteric venous rings. Finally, celiac ganglionectomy did not modify the magnitude of fall or time course of 5-HT-induced hypotension when compared to animals receiving sham ganglionectomy. We conclude it is unlikely 5-HT interacts with the sympathetic nervous system at the level of the splanchnic preganglionic or postganglionic nerve, as well as at the neuroeffector junction, to reduce blood pressure. These important studies allow us to rule out a direct interaction of 5-HT with the splanchnic sympathetic nervous system as a cause of the 5-HT-induced fall in blood pressure. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Upregulation of 5-Hydroxytryptamine Receptor Signaling in Coronary Arteries after Organ Culture

    PubMed Central

    Rao, Fang; Xue, Yu-Mei; Zhou, Zhi-Ling; Liu, Xiao-Ying; Shan, Zhi-Xin; Li, Xiao-Hong; Lin, Qiu-Xiong; Wu, Shu-Lin; Yu, Xi-Yong

    2014-01-01

    Background 5-Hydroxytryptamine (5-HT) is a powerful constrictor of coronary arteries and is considered to be involved in the pathophysiological mechanisms of coronary-artery spasm. However, the mechanism of enhancement of coronary-artery constriction to 5-HT during the development of coronary artery disease remains to be elucidated. Organ culture of intact blood-vessel segments has been suggested as a model for the phenotypic changes of smooth muscle cells in cardiovascular disease. Methodology/Principal Findings We wished to characterize 5-HT receptor-induced vasoconstriction and quantify expression of 5-HT receptor signaling in cultured rat coronary arteries. Cumulative application of 5-HT produced a concentration-dependent vasoconstriction in fresh and 24 h-cultured rat coronary arteries without endothelia. 5-HT induced greater constriction in cultured coronary arteries than in fresh coronary arteries. U46619- and CaCl2-induced constriction in the two groups was comparable. 5-HT stimulates the 5-HT2A receptor and cascade of phospholipase C to induce coronary vasoconstriction. Calcium influx through L-type calcium channels and non-L-type calcium channels contributed to the coronary-artery constrictions induced by 5-HT. The contractions mediated by non-L-type calcium channels were significantly enhanced in cultured coronary arteries compared with fresh coronary arteries. The vasoconstriction induced by thapsigargin was also augmented in cultured coronary arteries. The decrease in Orai1 expression significantly inhibited 5-HT-evoked entry of Ca2+ in coronary artery cells. Expression of the 5-HT2A receptor, Orai1 and STIM1 were augmented in cultured coronary arteries compared with fresh coronary arteries. Conclusions An increased contraction in response to 5-HT was mediated by the upregulation of 5-HT2A receptors and downstream signaling in cultured coronary arteries. PMID:25202989

  5. Inhibition by 5-hydroxytryptamine and noradrenaline in substantia gelatinosa of guinea-pig spinal trigeminal nucleus.

    PubMed

    Grudt, T J; Williams, J T; Travagli, R A

    1995-05-15

    1. Whole-cell and intracellular recordings were made from neurons in slices of guinea-pig spinal trigeminal nucleus pars caudalis. 2. 5-Hydroxytryptamine (5-HT) hyperpolarized 70% of neurons by activating 5-HT1A receptors. The effect was mimicked by 5-carboxamidotryptamine (5-CT) and (+/-)-2-dipropylamino-8-hydroxy-1,2,3,4-tetrahydronapthalene hydrobromide (8-OH-DPAT) and antagonized by 1-(2-methoxyphenyl)-4-[4-(2-phthalimido)-butyl]-piperazine hydrobromide (NAN 190) and pindobind-5-HT1A. Nine per cent of the neurons were depolarized by 5-HT. 3. In about 20% of recordings, 5-HT also evoked repetitive inhibitory postsynaptic potentials that were mediated by glycine. 4. Noradrenaline (NA) hyperpolarized 71% of neurons. This effect was mediated by activation of alpha 2-adrenoceptors, since 5-bromo-N-(4,5-dihydro-1H-imidazol-2-yl)-6-quinoxalinamine (UK14304) also caused a hyperpolarization and idazoxan (1 microM) blocked the hyperpolarization to both NA and UK14304. Phenylephrine depolarized a subset of neurons and this depolarization was blocked by prazosin, suggesting an action mediated by activation of alpha 1-adrenoceptors. 5. NA also evoked repetitive GABAA-mediated inhibitory postsynaptic potentials in about 20% of recordings. The increase in synaptic activity was mimicked by phenylephrine and blocked by prazosin. 6. These results indicate that there are at least two mechanisms through which 5-HT and NA inhibit neurons: (i) in many cells both 5-HT and NA mediate a hyperpolarization through an increase of a potassium conductance; (ii) 5-HT and NA also activated GABA- and glycine-containing interneurons to cause IPSPs in separate groups of cells.

  6. TRPA1, substance P, histamine and 5-hydroxytryptamine interact in an interdependent way to induce nociception.

    PubMed

    Fischer, Luana; Lavoranti, Maria Isabel; de Oliveira Borges, Mariana; Miksza, Alana Farias; Sardi, Natalia Fantin; Martynhak, Bruno Jacson; Tambeli, Claudia H; Parada, Carlos Amílcar

    2017-04-01

    Although TRPA1, SP, histamine and 5-hydroxytryptamine (5-HT) have recognized contribution to nociceptive mechanisms, little is known about how they interact with each other to mediate inflammatory pain in vivo. In this study we evaluated whether TRPA1, SP, histamine and 5-HT interact, in an interdependent way, to induce nociception in vivo. The subcutaneous injection of the TRPA1 agonist allyl isothiocyanate (AITC) into the rat's hind paw induced a dose-dependent and short lasting behavioral nociceptive response that was blocked by the co-administration of the TRPA1 antagonist, HC030031, or by the pretreatment with antisense ODN against TRPA1. AITC-induced nociception was significantly decreased by the co-administration of selective antagonists for the NK1 receptor for substance P, the H1 receptor for histamine and the 5-HT1A or 3 receptors for 5-HT. Histamine- or 5-HT-induced nociception was decreased by the pretreatment with antisense ODN against TRPA1. These findings suggest that AITC-induced nociception depends on substance P, histamine and 5-HT, while histamine- or 5-HT-induced nociception depends on TRPA1. Most important, AITC interact in a synergistic way with histamine, 5-HT or substance P, since their combination at non-nociceptive doses induced a nociceptive response much higher than that expected by the sum of the effect of each one alone. This synergistic effect is dependent on the H1, 5-HT1A or 3 receptors. Together, these findings suggest a self-sustainable cycle around TRPA1, no matter where the cycle is initiated each step is achieved and even subeffective activation of more than one step results in a synergistic activation of the overall cycle.

  7. Kinetics of competitive drug action at 5-hydroxytryptamine2 receptors in isolated rabbit aorta.

    PubMed

    Clancy, B M; Osman, R; Maayani, S

    1987-07-01

    The kinetics of agonist and antagonist interactions with the 5-hydroxytryptamine2 receptor were studied in the isolated rabbit aorta by following the antagonist-induced decrease in the steady-state response to an agonist. A model describing the competitive drug-receptor interactions was fitted to the data and yielded estimates of the association and dissociation rate constants of the agonist and the antagonist. A high concentration of the agonist ([agonist] much greater than KA) was used to reduce the influence of antagonist diffusion to the receptor upon the onset of antagonism. The effect of a diffusion barrier was evaluated by comparing the kinetics of drug competition in the absence and in the presence of the adventitia. The rate constants of the high-affinity antagonists spiperone, methysergide or ketanserin were similar in the absence and in the presence of the adventitia. In contrast, the rate constants of the low affinity antagonist 5-methoxygramine were reduced almost 5-fold in the presence of the adventitia. This observation may be explained by the large partition coefficients of the high-affinity antagonists as compared to the relatively low partition coefficient of 5-methoxygramine. The ratios of the estimated rate constants (k-x/kx) are in good agreement with the dissociation constants of the drugs determined with steady-state methods. In addition the results suggest that the association rate constant is a primary determinant of drug affinity for the receptor. The kinetic rate constants of the high-affinity antagonists measured in this preparation are similar to those previously reported in high-affinity binding studies. We conclude that the kinetic parameters obtained in our experiments reflect primarily the molecular interactions of these drugs with the receptor.

  8. Signal transduction differences between 5-hydroxytryptamine type 2A and type 2C receptor systems.

    PubMed

    Berg, K A; Clarke, W P; Sailstad, C; Saltzman, A; Maayani, S

    1994-09-01

    The cDNAs for human 5-hydroxytryptamine (5-HT)2C and 5-HT2A receptors were stably transfected separately into parent Chinese hamster ovary cells, and cell lines in which levels of transfected receptor protein expression and accumulation of inositol phosphates in response to 5-HT were comparable were chosen for study. The effect of activation of these receptors on 5-HT1B-like receptor-mediated responsiveness (i.e., inhibition of forskolin-stimulated cAMP accumulation) was studied. Activation of 5-HT2C receptors with 5-HT (0.1-100 microM) abolished the 5-HT1B-like response, which returned when 5-HT2C receptors were blocked with mesulergine (1 microM). Furthermore, the maximal response to 5-carboxytryptamine was reduced in a concentration-dependent manner by the 5-HT2A/5-HT2C-selective partial agonist (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane. In contrast, activation of 5-HT2A receptors with either 5-HT or (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane did not alter the 5-HT1B-like response. The reduction of 5-HT1B-like responsiveness produced by 5-HT2C receptor activation was independent of protein kinase C activation and increases in the intracellular calcium concentration. Although 5-HT2A and 5-HT2C receptors are strikingly similar in structure and pharmacology, and the signal transduction systems coupled to these receptors have been thought to be similar, if not identical, these data provide the first evidence for fundamental differences in the signal transduction systems of these 5-HT2 receptor subtypes.

  9. Lamotrigine, carbamazepine and phenytoin differentially alter extracellular levels of 5-hydroxytryptamine, dopamine and amino acids.

    PubMed

    Ahmad, Shagufta; Fowler, Leslie J; Whitton, Peter S

    2005-02-01

    We have studied the effects of treatment with the anticonvulsants lamotrigine (LTG), phenytoin (PHN) and carbamazepine (CBZ) on basal and stimulated extracellular aspartate (ASP), glutamate (GLU), taurine (TAU), GABA, 5-hydroxytryptamine (5-HT) and dopamine (DA) in the hippocampus of freely moving rats using microdialysis. All of the drugs investigated have had inhibition of Na(+) channel activity implicated as their principal mechanism of action. Neither LTG (10-20 mg/kg), PHN (20-40 mg/kg) or CBZ (10-20 mg/kg) had an effect on the basal extracellular concentrations of any of the amino acids studied with the exception of glutamate, which was decreased at the highest LTG dose. However, when amino acid transmitter levels were increased with 50 microM veratridine, LTG was found to cause a dose-dependent decrease in dialysate levels of all four amino acids, with the effect being most pronounced for glutamate. In contrast, PHN decreased extracellular aspartate levels but had no effect on evoked-extracellular GLU, TAU or GABA. Somewhat unexpectedly, CBZ did not alter the stimulated increase in the excitatory amino acids, GLU and ASP, but, rather surprisingly for an antiepileptic drug, markedly decreased that of the inhibitory substances TAU and GABA. The three drugs had differing effects on basal extracellular 5-HT and DA. LTG caused a dose-dependent decrease in both, while CBZ and PHN both increased extracellular 5-HT and DA. When extracellular 5-HT and DA was evoked by veratridine LTG had no significant effect on this, while PHN but not CBZ increased stimulated extracellular 5-HT and both PHN and CBZ augmented DA. Thus, the effects of the three drugs studied seemed to depend on whether extracellular transmitter levels are evoked or basal and the particular transmitter in question. This suggests that there are marked differences in the neurochemical mechanisms of antiepileptic drug action of the three compounds studied.

  10. Identification of 5-hydroxytryptamine1D binding sites in sheep caudate nucleus membranes.

    PubMed

    Pauwels, P J; Palmier, C; Briley, M

    1993-08-03

    Radioligand binding measurements were performed in membranes of sheep caudate nucleus using [3H]5-hydroxytryptamine (5-HT). [3H]5-HT labeled a population of high affinity binding sites with a Kd of 1.9 +/- 0.1 nM and a Bmax of 19.8 +/- 2.2 fmol/mg tissue. Combined 5-HTID/E binding sites were the predominant 5-HT1 subtype, accounting for 78% of the total population of 5-HT1 binding sites. 5-Carboxamidotryptamine (5-CT) and sumatriptan yielded inhibition curves which best fitted a two-site model with high affinity values of 0.8 and 10.1 nM, and 1000 and 206 nM for their low affinity components. The proportion of the high affinity 5-CT and sumatriptan binding sites was 79 and 72%. The binding affinity profile of 5-HT1D binding sites [5-CT > 5-HT > d-LSD > 5-MeOT > sumatriptan > RU 24,969 > metergoline > tryptamine = rauwolscine = methylsergide > yohimbine = methiothepin > TFMPP = 8-OH-DPAT > 2-methyl-5-HT > mCPP = quipazine = CP 93,129 > ketanserin > (-)-propranolol = haloperidol = ipsapirone] compares well to that reported for 5-HT1D receptor sites in human caudate and cortex (correlation coefficient: 0.99 and 0.98). The present results indicate that sheep caudate nucleus is a valid tissue for studying interaction of compounds with 5-HT1D binding sites in the relative absence of 5-HT1E binding sites.

  11. The 5-hydroxytryptamine 4 Receptor Agonist-induced Actions and Enteric Neurogenesis in the Gut

    PubMed Central

    Goto, Kei; Kawahara, Isao

    2014-01-01

    We explored a novel effect of 5-hydroxytryptamine 4 receptor (5-HT4R) agonists in vivo to reconstruct the enteric neural circuitry that mediates a fundamental distal gut reflex. The neural circuit insult was performed in guinea pigs and rats by rectal transection and anastomosis. A 5-HT4R-agonist, mosapride citrate (MOS) applied orally and locally at the anastomotic site for 2 weeks promoted the regeneration of the impaired neural circuit or the recovery of the distal gut reflex. MOS generated neurofilament-, 5-HT4R- and 5-bromo-2'-deoxyuridine-positive cells and formed neural network in the granulation tissue at the anastomosis. Possible neural stem cell markers increased during the same time period. These novel actions by MOS were inhibited by specific 5-HT4R-antagonist such as GR113808 (GR) or SB-207266. The activation of enteric neural 5-HT4R promotes reconstruction of an enteric neural circuit that involves possibly neural stem cells. We also succeeded in forming dense enteric neural networks by MOS in a gut differentiated from mouse embryonic stem cells. GR abolished the formation of enteric neural networks. MOS up-regulated the expression of mRNA of 5-HT4R, and GR abolished this upregulation, suggesting MOS differentiated enteric neural networks, mediated via activation of 5-HT4R. In the small intestine in H-line: Thy1 promoter green fluorescent protein (GFP) mice, we obtained clear 3-dimensional imaging of enteric neurons that were newly generated by oral application of MOS after gut transection and anastomosis. All findings indicate that treatment with 5-HT4R-agonists could be a novel therapy for generating new enteric neurons to rescue aganglionic disorders in the whole gut. PMID:24466442

  12. An update on the role of the 5-hydroxytryptamine6 receptor in cognitive function.

    PubMed

    Fone, Kevin C F

    2008-11-01

    As the 5-hydroxytryptamine(6) (5-HT(6)) receptor is almost exclusively expressed in the CNS, particularly in areas associated with learning and memory, many studies have examined its role in cognitive function in the rodent, as reviewed herein. Most studies, in healthy adult rats, report that 5-HT(6) receptor antagonists enhance retention of spatial learning in the Morris water maze, improve consolidation in autoshaping tasks and reverse natural forgetting in object recognition. Antagonists appear to facilitate both cholinergic and glutamatergic neurotransmission, reversing scopolamine- and NMDA receptor antagonist-induced memory impairments. Recent reports show that the 5-HT(6) receptor antagonist, PRX-07034, restores the impairment of novel object recognition produced in rats reared in social isolation, a neurodevelopmental model producing behavioural changes similar to several core symptoms seen in schizophrenia. The 5-HT(6) receptor antagonist, Ro 04-6790, modestly improved reversal learning in isolation reared but not group-housed controls in the water maze. Ro 04-6790 also improved novel object discrimination both in adult rats that received chronic intermittent phencyclidine and drug-naïve 18-month-old rats. However, more information on their effect in animal models of schizophrenia and Alzheimer's disease is required. Several selective high-affinity 5-HT(6) receptor agonists developed recently also improve object discrimination and extra-dimensional set-shifting behaviour. Thus both 5-HT(6) receptor agonist and antagonist compounds show promise as pro-cognitive agents in pre-clinical studies but the explanation for their paradoxical analogous effect is currently unclear, and is discussed in this article.

  13. Potentiation by endothelin-1 of 5-hydroxytryptamine-induced contraction in coronary artery of the pig.

    PubMed Central

    Nakayama, K.; Ishigai, Y.; Uchida, H.; Tanaka, Y.

    1991-01-01

    1. In order to elucidate the physiological and potential pathological roles of endothelin-1 (ET-1) in coronary artery contraction and relaxation, we undertook the present study to examine the action of ET-1 itself, and the combined effects of ET-1 with vasoconstrictor agonists such as acetylcholine (ACh), histamine, and 5-hydroxytryptamine (5-HT), all of which have been implicated in the genesis of coronary spasm. 2. Isometric tension and cytosolic Ca2+ concentration ([Ca2+]i) in a ring segment of porcine coronary artery loaded with fura-2 were measured simultaneously. 3. ET-1 contracted the artery in a concentration-dependent manner; and nisoldipine, a Ca2+ channel blocking drug of the 1,4-dihydropyridine type, antagonized the ET-1 action non-competitively. A radio-receptor binding assay also indicated the mutually exclusive binding of ET-1 and (+)-[3H]-PN200-110, a Ca2+ channel ligand, to the membrane fraction of porcine coronary artery. 4. ET-1 (10-100 pM) increased tension and [Ca2+]i in a parallel manner, while at higher concentrations (1-10 nM) it produced further contraction with a small increase in [Ca2+]i. 5. ET-1 (30-100 pM) selectively potentiated the 5-HT-induced contraction 1.5 to 2 times over the control without causing a significant increase in [Ca2+]i, which seems to be qualitatively similar to a tumour promoting phorbol ester, 12-deoxyphorbol 13-isobutylate (DPB). Bay K 8644 (10 nM), on the other hand, potentiated the contraction in response to practically all agonists used and affected a concomitant increase in [Ca2+]i.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1810605

  14. Increased responsiveness to 5-hydroxytryptamine after antigenic challenge is inhibited by nifedipine and niflumic acid in rat trachea in vitro.

    PubMed

    Moura, Carlos Tiago Martins; Bezerra, Fernanda Carvalho; de Moraes, Isabelle Maciel; Magalhães, Pedro Jorge Caldas; Capaz, Francisco Ruy

    2005-12-01

    Antigenic challenge often induces hyperreactivity in asthmatic airway, although the precise mechanism(s) underlying this increased responsiveness is not entirely known. Tracheae obtained from ovalbumin (OVA)-sensitized saline- or OVA-challenged rats were placed in 10 mL bath chambers for isometric recording of 5-hydroxytryptamine (5-HT)-induced contractions. 5-Hydroxytryptamine induced a stronger contraction compared with control in antigen-challenged trachea under normal or Ca2+-free conditions. In tracheae pretreated with the L-type Ca2+ channel blocker nifedipine (10(-6) mol/L) or the Ca2+-activated Cl- channel blocker niflumic acid (10(-4) mol/L), this hyperresponsiveness was not developed in either normal or Ca2+-free medium. The increased contractile response to 5-HT in allergic rat isolated trachea may be related to a greater ionic (Ca2+ and Cl-) channel involvement.

  15. Inhibitory 5-hydroxytryptamine receptors involved in pressor effects obtained by stimulation of sympathetic outflow from spinal cord in pithed rats.

    PubMed Central

    Morán, A; Velasco, C; Salvador, T; Martín, M L; San Román, L

    1994-01-01

    1. A study was made of the effects of 5-hydroxytryptamine (5-HT) on pressor response induced in vivo by electrical stimulation of the sympathetic outflow from the spinal cord of pithed rats. All animals had been pretreated with atropine. Intravenous infusion of 5-hydroxytryptamine at doses of 10 and 20 micrograms kg-1 min-1 reduced the pressor effects obtained by electrical stimulation at intervals of 10 min over the 1 h of infusion. 2. This inhibitory action of 5-HT was depressed by cyproheptadine and methiothepin but was not modified by ketanserin or MDL-72222. By contrast, the inhibitory action of 5-HT was lost in pithed rats that had been pretreated with exogenous noradrenaline. 3. The 5-HT1 receptor agonist 5-carboxamidotryptamine (5-CT) caused an inhibition of the pressor response, whereas the 5-HT3 receptor agonist, 1-phenylbiguanide, produced a variable but significant increase in the pressor response. The 5-HT2 receptor agonist, m-CPP, did not modify the pressor sympathetic response. 4. Our results suggest that 5-hydroxytryptamine interferes with sympathetic neurotransmission by inhibiting pressor effects as a result of stimulation of the complete sympathetic outflow, and that this inhibition is mainly through a presynaptic 5-HT1 mechanism. PMID:7889292

  16. 5-hydroxytryptamine stimulation of phospholipase D activity in the rabbit isolated mesenteric artery.

    PubMed

    Hinton, J M; Adams, D; Garland, C J

    1999-04-01

    1. The involvement of phospholipase D (PLD) in the 5-hydroxytryptamine 5-HT1B/5-HT1D-signalling pathway was assessed in the rabbit isolated mesenteric artery. 2. RT-PCR analysis of mesenteric smooth muscle cells revealed a strong signal corresponding to mRNA transcript for the 5-HT1B receptor. The PCR fragment corresponded to the known sequence for the 5-HT1B receptor. No signal corresponding to 5-HT1D mRNA was detected. 3. Neither 5-HT (3 microM) nor KCl (45 mM) individually stimulated any significant increase in the smooth muscle concentration of [33P]-PtdBut to reflect PLD activity. However, in the presence of KCl (45 mM), 5-HT evoked a concentration-dependent increase in [33P]-PtdBut, to a maximum of 84% with 5-HT (3 microM). 4. [33P]-PtdBut accumulation evoked by 5-HT in the presence of KCl was abolished in nominally calcium-free Krebs-Henseleit Buffer (KHB) or with the selective protein kinase C inhibitor, Ro-31 8220 (10 microM, 20 min). 5. 5-HT (3 microM) in the presence of KCl (45 mM) failed to increase either the accumulation of [33P]-phosphatidic acid in the presence of butanol, or total [3H]-inositol phosphates ([3H]-InsP) in the presence of LiCl (10 mM). 6. 5-HT (0.1-1 microM) abolished forskolin (1 microM) stimulated increases in cyclic AMP (15 fold increase), an action which was pertussis toxin-sensitive. 7. Therefore, in the presence of raised extracellular potassium 5-HT can stimulate PLD via 5-HT1B receptors in the rabbit mesenteric artery. This action requires extracellular calcium and the activation of protein kinase C. These characteristics are identical to the profile for 5-HT1B/5-HT1D-receptor evoked contraction in vascular smooth muscle cells, suggesting a role for PLD in this response to 5-HT.

  17. Meta-analysis of 5-hydroxytryptamine type 2A receptor polymorphisms and migraine susceptibility.

    PubMed

    Peng, Jian-Ming; Yu, You-Jiang; Su, Lan-Di; Luo, Xue

    2014-12-01

    Epidemiologic studies have investigated the association of polymorphisms in 5-hydroxytryptamine type 2A receptor (5HT2A) gene and migraine susceptibility, but the results of those studies are inconclusive. To obtain a more systematic estimation of the association, we conducted a comprehensive search to examine all the eligible studies of 5HT2A polymorphisms and migraine risk. The odd ratios (ORs) with 95% confidence intervals (CIs) were used to determine the strength of the association. Publication bias was analyzed by Begg's funnel plots. Seven eligible studies regarding 5HT2A T102C and A-1438G polymorphisms with 721 cases and 713 controls were included in this meta-analysis. Overall, no significant associations were found between 5HT2A T102C (for T vs. C: OR = 1.029, 95% CI = 0.870-1.217, p = 0.739; for TT vs. CC: OR = 1.083, 95% CI = 0.760-1.544, p = 0.657; for TT + TC vs. CC: OR = 1.066, 95% CI = 0.802-1.416, p = 0.662; for TT vs. TC + CC: OR = 1.017, 95% CI = 0.774-1.336, p = 0.904) or A-1438G (for T vs. C: OR = 0.996, 95% CI = 0.726-1.365, p = 0.979; for TT vs. CC: OR = 0.983, 95% CI = 0.511-1.891, p = 0.960; for TT + TC vs. CC: OR = 1.118, 95% CI = 0.654-1.910, p = 0.684; for TT vs. TC + CC: OR = 0.890, 95% CI = 0.528-1.499, p = 0.661) polymorphisms and migraine risk. The further subgroup analysis by ethnicity, assay and disease type also found no significant association using four genetic models. Meanwhile, the publication bias analysis suggests that there is no publication bias in these studies. In conclusion, our current meta-analysis implies that 5HT2A T102C and A-1438G polymorphisms may be not risk factors in the pathogenesis of migraine.

  18. Functional properties of a cloned 5-hydroxytryptamine ionotropic receptor subunit: comparison with native mouse receptors.

    PubMed Central

    Hussy, N; Lukas, W; Jones, K A

    1994-01-01

    1. A comparative study of the whole-cell and single-channel properties of cloned and native mouse 5-hydroxytryptamine ionotropic receptors (5-HT3) was undertaken using mammalian cell lines expressing the cloned 5-HT3 receptor subunit A (5-HT3R-A), superior cervical ganglia (SCG) neurones and N1E-115 cells. 2. No pharmacological difference was found in the sensitivity to the agonists 5-HT and 2-methyl-5-HT, or to the antagonists d-tubocurare and 3-tropanyl-3,5-dichlorobenzoate (MDL-72222). 3. Current-voltage (I-V) relationships of whole-cell currents showed inward rectification in the three preparations. Rectification was stronger both in cells expressing the 5-HT3R-A subunit and in N1E-115 cells when compared with SCG neurones. 4. No clear openings could be resolved in 5-HT-activated currents in patches excised from cells expressing the 5-HT3R-A subunit or N1E-115 cells. Current fluctuation analysis of whole-cell and excised-patch records revealed a slope conductance of 0.4-0.6 pS in both preparations. Current-voltage relationships of these channels showed strong rectification that fully accounted for the whole-cell voltage dependence. 5. In contrast, single channels of about 10 pS were activated by 5-HT in patches excised from SCG neurones. The weak voltage dependence of their conductance did not account completely for the rectification of whole-cell currents. A lower unitary conductance (3.4 pS) was inferred from whole-cell noise analysis. 6. We conclude that the receptor expressed from the cloned cDNA is indistinguishable from the 5-HT3 receptor of N1E-115 cells, suggesting an identical structure for these two receptors. The higher conductance and different voltage dependence of the 5-HT3 receptor in SCG neurones might indicate the participation of an additional subunit in the structure of native ganglionic 5-HT3 receptors. Homo-oligomeric 5-HT3R-A channels may also be present as suggested by the lower conductance estimated by whole-cell noise analysis. PMID

  19. Stimulation and inhibition of adenylyl cyclase by distinct 5-hydroxytryptamine receptors.

    PubMed

    De Vivo, M; Maayani, S

    1990-10-01

    5-Hydroxytryptamine (serotonin, 5-HT) stimulates basal adenylyl cyclase activity in membranes from guinea pig or rat hippocampi, but 5-HT inhibits forskolin-stimulated adenylyl cyclase activity in these same membranes. The opposing effects of 5-HT on adenylyl cyclase activity indicate that distinct 5-HT receptors, positively and negatively coupled to adenylyl cyclase, are present in these membranes. Stimulation of adenylyl cyclase activity is mediated by two distinct 5-HT receptors. The receptor with lower affinity for 5-HT, designated as RL, is apparently homologous with a 5-HT receptor present in rat collicular membranes, but it is not homologous with the stimulatory receptor characterized in neuroblastoma hybrid cell (NCB-20) membranes. The receptor with higher affinity for 5-HT is homologous with the 5-HT1A binding site. The magnitude of stimulation by 5-HT1A receptors is variable with respect to stimulation by RL and is sometimes completely absent. Inhibition of forskolin-stimulated adenylyl cyclase activity, in membranes from either rat or guinea pig hippocampus or rat cortex, is a functional correlate of the 5-HT1A binding site. This inhibitory response was used to determine the pharmacological characteristics of drugs that reportedly have high affinity for 5-HT1A binding sites, such as 1-[2-(4-aminophenyl)ethyl]-4-(3-trifluoromethylphenyl)piperazine (PAPP) and (-)pindolol. PAPP inhibited adenylyl cyclase activity in guinea pig hippocampal membranes with an EC50 value of 27 +/- 3 nM. (-)Pindolol was a partial agonist in inhibiting adenylyl cyclase activity in guinea pig and rat hippocampal membranes. Because of the low intrinsic activity of (-)pindolol, it was tested as an antagonist of the inhibition produced by 5-HT1A receptor agonists in rat hippocampal membranes. The Kb of (-)pindolol was 40 nM as measured by a Schild plot. (-)Propranolol was a simple competitive antagonist at the rat hippocampal receptor with a Kb value of 550 nM. In summary, guinea pig

  20. Oxidation of tryptamine and 5-hydroxytryptamine: a pulse radiolysis and quantum chemical study.

    PubMed

    Gaikwad, P; Priyadarsini, K I; Naumov, S; Rao, B S M

    2009-07-23

    The reactions of oxidizing radicals (*)OH, N(3)(*), Br(2)(*-), and NO(2)(*) with tryptamine (Tpe) and 5-hydroxytryptamine (HTpe) were studied by pulse radiolysis and analyzed by quantum chemical calculations. Barring NO(2)(*) radical, the rate constants for their reaction with Tpe and HTpe were found to be diffusion controlled and the rates in the NO(2)(*) radical reaction with HTpe are lower by 2 orders of magnitude with k approximately 1 x 10(7) dm(3) mol(-1) s(-1). The transient spectra formed on oxidation of Tpe and HTpe exhibited peaks at 330 and 530 nm (indolyl radical) and 420 nm (indoloxyl radical), respectively, and the latter is in reasonable agreement with the calculated value (407 nm). Both radicals decay through direct recombination, but only the indoloxyl radical was observed to react with the parent molecule to give a (HTpe-Ind)(*) radical adduct for [HTpe] > or = 50 x 10(-6) mol dm(-3). The calculated optimized geometries in water revealed the formation of two distinct types of radical adducts, one through the H-O bond and the other by C-C linkage. The H-O bonded radical adduct was found to be exothermic with a reaction enthalpy of -4 kcal mol(-1) and bond length 0.1819 nm and the C-C bonded radical adducts are endothermic and rate determining but are finally driven by exothermic processes involving intermolecular H transfer followed by intramolecular reorganization through H shift resulting in stable C4-C4' and C2-C4' dimers with reaction enthalpies of -39 and -44 kcal mol(-1), respectively, and this process was found to be thermodynamically as efficient as direct recombination of indoloxyl radicals. The formation of the two dimer products was also seen in steady-state radiolysis. The lack of adduct formation in the case of indolyl radical with Tpe is due to the positive free energy change (DeltaG = 10 kcal mol(-1)). The energetics for the (*)OH addition have shown dependence on the site of activation with (HTpe-OH)(*) adducts at C2 and C4 and the

  1. Chemistry and biology of the compounds that modulate cell migration.

    PubMed

    Tashiro, Etsu; Imoto, Masaya

    2016-03-01

    Cell migration is a fundamental step for embryonic development, wound repair, immune responses, and tumor cell invasion and metastasis. Extensive studies have attempted to reveal the molecular mechanisms behind cell migration; however, they remain largely unclear. Bioactive compounds that modulate cell migration show promise as not only extremely powerful tools for studying the mechanisms behind cell migration but also as drug seeds for chemotherapy against tumor metastasis. Therefore, we have screened cell migration inhibitors and analyzed their mechanisms for the inhibition of cell migration. In this mini-review, we introduce our chemical and biological studies of three cell migration inhibitors: moverastin, UTKO1, and BU-4664L.

  2. Identification of 5-hydroxytryptamine receptors positively coupled to adenylyl cyclase in rat cultured astrocytes

    PubMed Central

    Hirst, Warren D; Price, Gary W; Rattray, Marcus; Wilkin, Graham P

    1997-01-01

    5-Hydroxytryptamine (5-HT) elicited a dose-dependent stimulation of intracellular adenosine 3′ : 5′-cyclic monophosphate (cyclic AMP) accumulation in cultured astrocytes derived from neonatal rat (Sprague Dawley) thalamic/hypothalamic area with a potency (pEC50) of 6.68±0.08 (mean±s.e.mean).In order to characterize the 5-HT receptor responsible for the cyclic AMP accumulation the effects of a variety of compounds were investigated on basal cyclic AMP levels (agonists) and 5-carboxamidotryptamine (5-CT) stimulated cyclic AMP levels (antagonists). The rank order of potency for the agonists investigated was 5-CT (pEC50=7.81±0.09)>5-methoxytryptamine (5-MeOT) (pEC50=6.86±0.36)>5-HT (pEC50=6.68±0.08). The following compounds, at concentrations up to 10 μM, did not affect basal cyclic AMP levels 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), cisapride, sumatriptan, DOI and RU 24969. The rank order of potency of antagonists was meth- iothepin (pKi=7.98±0.25)>mesulergine (pKi=7.58±0.18)>ritanserin (pKi=7.20±0.24)>clozapine (pKi=7.03±0.19)>mianserin (pKi=6.41±0.19). The following compounds, at concentrations up to 10 μM, were inactive: ketanserin, WAY100635, GR127935. This pharmacological profile is consistent with that of 5-HT7 receptor subtype-mediated effects.The cultured astrocytes exhibited regional heterogeneity in the magnitude of cyclic AMP accumulation (Emax). Cells cultured from the thalamic/hypothalamic area had significantly higher Emax values (588±75% and 572±63% of basal levels for 5-CT and 5-HT, respectively) compared to brainstem (274±51% and 318±46%, respectively) and colliculus astrocytes (244±15% and 301±24%, respectively). No significant differences in pEC50 (for either 5-HT or 5-CT) values were observed.Reverse transcriptase-polymerase chain reaction (RT–PCR) with primers specific for the 5-HT7 receptor confirmed expression of messenger RNA for this receptor subtype by the cultured astrocytes derived from all regions

  3. Structural basis of the anti-inflammatory activity of quercetin: inhibition of the 5-hydroxytryptamine type 2 receptor.

    PubMed

    Rotelli, Alejandra Ester; Aguilar, Carlos Fernando; Pelzer, Lilian Eugenia

    2009-09-01

    The anti-inflammatory activity of quercetin was evaluated through serotonin-induced rat-paw edema. The experiments showed that quercetin had an important effect on acute inflammatory processes. Docking of serotonin and quercetin into the homology model of the 5-Hydroxytryptamine Type 2 Receptor allowed to analyze the structural basis of the anti-inflammatory activity. Results showed that serotonin and quercetin bind in the same region of the active site with a similar binding energy but quercetin has a much bigger inhibition constant. Therefore, it seems possible that quercetin may act as a natural inhibitor of the receptor blocking the acute inflammation generated by serotonin.

  4. KIBRA Modulates Directional Migration of Podocytes

    PubMed Central

    Duning, Kerstin; Schurek, Eva-Maria; Schlüter, Marc; Bayer, Michael; Reinhardt, Hans-Christian; Schwab, Albrecht; Schaefer, Liliana; Benzing, Thomas; Schermer, Bernhard; Saleem, Moin A.; Huber, Tobias B.; Bachmann, Sebastian; Kremerskothen, Joachim; Weide, Thomas; Pavenstädt, Hermann

    2008-01-01

    Asymmetric delivery and distribution of macromolecules are essential for cell polarity and for cellular functions such as differentiation, division, and signaling. Injury of podocytes, which are polarized epithelial cells, changes the dynamics of the actin meshwork, resulting in foot process retraction and proteinuria. Although the spatiotemporal control of specific protein–protein interactions is crucial for the establishment of cell polarity, the mechanisms controlling polarity-dependent differentiation and division are incompletely understood. In this study, yeast two-hybrid screens were performed using a podocyte cDNA library and the polarity protein PATJ as bait. The protein KIBRA was identified as an interaction partner of PATJ and was localized to podocytes, tubular structures, and collecting ducts. The last four amino acids of KIBRA mediated binding to the eighth PDZ domain of PATJ. In addition, KIBRA directly bound to synaptopodin, an essential organizer of the podocyte cytoskeleton. Stable knockdown of KIBRA in immortalized podocytes impaired directed cell migration, suggesting that KIBRA modulates the motility of podocytes by linking polarity proteins and cytoskeleton-associated protein complexes. PMID:18596123

  5. The action of 5-hydroxytryptamine and related compounds on the activity of retzius cells of the leech Hirudo medicinalis

    PubMed Central

    Smith, P.A.; Walker, R.J.

    1974-01-01

    1 The equipotent molar ratios of a range of tryptamine analogues, as compared with 5-hydroxytryptamine (5-HT), have been determined on the basis of their ability to hyperpolarize the membrane potential of the Retzius cell of the leech, Hirudo medicinalis. 2 The substitution of methyl, fluoro, chloro, methoxy or acetyl groups onto the 5-HT molecule progressively reduced the potency. 3 5-Methoxylation or terminal N-methylation of tryptamine considerably increased the potency of tryptamine but these compounds tended to depolarize cells rather than cause hyperpolarization. In some experiments they were ineffective on preparations pretreated with 5-HT. 4 It is suggested that these compounds may act by a different mechanism from the 5-hydroxylated indoles, perhaps involving a different receptor. PMID:4441793

  6. The effect of DA-9701 on 5-hydroxytryptamine-induced contraction of feline esophageal smooth muscle cells.

    PubMed

    Oh, Kyung Hoon; Nam, Yoonjin; Jeong, Ji Hoon; Kim, In Kyeom; Sohn, Uy Dong

    2014-04-22

    Serotonin, or 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter found in blood platelets, the gastrointestinal (GI) tract, and the central nervous system (CNS) of animals and humans. The signaling pathways of 5-hydroxytryptamine (5-HT)-induced contractions in cat esophageal smooth muscle cell (ESMC)s have been identified, but the downstream components of the 5-HT signaling pathway remain unclear. DA-9701 is the standardized extract of the Pharbitis nil Choisy seed (Pharbitidis Semen, Convolvulaceae) and the root of Corydalis yahusuo W.T. Wang (Corydalis Tuber, Papaveraceae). DA-9701 is known to have strong gastroprokinetic effects and a good safety profile. In this study, we investigated the 5-HT signaling pathway at the G-protein level, and we explored the mechanisms by which DA-9701 induces smooth muscle contraction. Freshly isolated smooth muscle cells were harvested from the feline esophagus, and cells were permeabilized to measure their length. 5-HT produced esophageal smooth muscle contractions in a dose-dependent manner. Furthermore, 5-HT produced a relatively long-acting contraction. 5-HT binds to the 5-HT2, 5-HT3 and 5-HT4 receptors to induce smooth muscle contraction in feline ESMCs. These receptors, which are located in esophageal smooth muscle, are coupled to Gαq, Gαo and Gαs. These G proteins activate PLC, which leads to Ca2+/calmodulin-dependent MLCK activation, resulting in MLC20 phosphorylation and cell contraction. Conversely, DA-9701 inhibits 5-HT-induced contraction by inhibiting MLC20 phosphorylation.

  7. Selective 5-hydroxytryptamine2 antagonists have antidepressant-like effects on differential-reinforcement-of-low-rate 72-second schedule.

    PubMed

    Marek, G J; Li, A A; Seiden, L S

    1989-07-01

    The effects of eleven 5-hydroxytryptamine antagonists with varying selectivity for the 5-hydroxytryptamine2 (5-HT2) relative to the 5-HT1 binding site were assessed in rats responding under a differential-reinforcement-of-low rate 72-sec (DRL 72-s) schedule of reinforcement. Three drugs with a 1000-fold selectivity for the 5-HT2 binding site (ketanserin, ritanserin, pipamperone) increased the reinforcement rate and decreased the response rate similar to antidepressant drugs. The two drugs with roughly the same affinity for both 5-HT1 and 5-HT2 binding sites (methysergide and metergoline) did not increase the reinforcement rate. The maximal increase in the reinforcement rate after 5-HT antagonist administration was positively correlated with the selectivity of the 5-HT antagonists for the 5-HT2 versus the 5-HT1 binding site. The increase in the reinforcement rate after administration of 5-HT antagonists was not correlated with the affinity of the 5-HT antagonists for the alpha-1 adrenergic, alpha-2 adrenergic, histamine-1 or dopamine-2 receptors. The 1000-fold selective 5-HT2 antagonist xylamidine, which does not pass the blood-brain barrier, did not increase the reinforcement rate or decrease the response rate. Thus, selective antagonism of central 5-HT2 relative to 5-HT1 receptors results in antidepressant-like effects on the DRL 72-s schedule. Furthermore, the specificity of the DRL 72-s schedule as a screen for antidepressant drugs was strengthened by the observation that the alpha-1 adrenergic antagonist, prazosin, did not increase the reinforcement rate despite significant decreases in the response rate.

  8. 5-Hydroxytryptamine selectively activates the vagal nodose C-fibre subtype in the guinea-pig oesophagus.

    PubMed

    Yu, S; Ru, F; Ouyang, A; Kollarik, M

    2008-09-01

    The afferent neurons innervating the oesophagus originate from two embryonic sources: neurons located in vagal nodose ganglia originate from embryonic placodes and neurons located in vagal jugular and spinal dorsal root ganglia (DRG) originate from the neural crest. Here, we address the hypothesis that 5-hydroxytryptamine (5-HT) differentially stimulates afferent nerve subtypes in the oesophagus. Extracellular recordings of single unit activity originating from nerve terminals were made in the isolated innervated guinea-pig oesophagus. Whole cell patch clamp recordings (35 degrees C) were made from the primary afferent neurons retrogradely labelled from the oesophagus. 5-Hydroxytryptamine (10 micromol L(-1)) activated vagal nodose C-fibres (70%) in the oesophagus but failed to activate overtly vagal jugular nerve fibres and oesophagus-specific spinal DRG neurons. The response to 5-HT in nodose C-fibre nerve terminals was mimicked by the selective 5-HT(3) receptor agonist 2-methyl-5-HT (10 micromol L(-1)) and nearly abolished by the 5-HT(3) receptor antagonists ondansetron (10 micromol L(-1)) and Y-25130 (10 micromol L(-1)). In patch clamp studies, 2-methyl-5-HT (10 micromol L(-1)) activated a proportion of isolated oesophagus-specific nodose capsaicin-sensitive neurons (putative cell bodies of nodose C-fibres). We conclude that the responsiveness to 5-HT discriminates placode-derived (vagal nodose) C-fibres from the neural crest-derived (vagal jugular and spinal DRG) afferent nerves in the oesophagus. The response to 5-HT in nodose C-fibres is mediated by the 5-HT(3) receptor in their neuronal membrane.

  9. High-level stable expression of recombinant 5-HT1A 5-hydroxytryptamine receptors in Chinese hamster ovary cells.

    PubMed Central

    Newman-Tancredi, A; Wootton, R; Strange, P G

    1992-01-01

    The human 5-hydroxytryptamine 5-HT1A receptor gene was transfected into Chinese hamster ovary cells. A series of recombinant monoclonal cell lines expressing the receptor were isolated and the properties of one cell line that expressed receptors at a high level (2.8 pmol/mg) were studied in detail. In ligand binding assays with the selective 5-HT1A receptor agonist 2-(NN-di[3H]propylamino)-8-hydroxy-1,2,3,4-tetrahydronaphthalene ([3H]8-OH-DPAT) only a single class of saturable high-affinity binding sites was detected, with a pharmacological profile in competition experiments essentially identical to that of the 5-HT1A receptor of bovine hippocampus. [3H]8-OH-DPAT binding to the recombinant cell membranes was inhibited by GTP, showing that the receptors in the transfected cells couple to G-proteins. A series of 5-hydroxytryptamine agonists inhibited forskolin-stimulated adenylate cyclase activity in the cells and, despite the high level of receptor expression, their apparent efficacies were similar to those observed for inhibition of adenylate cyclase in brain. This recombinant cell line provides a complete model system for studying the 5-HT1A receptor and its transmembrane signalling system. The recombinant cells can also be grown in suspension culture for long periods but, whereas 5-HT1A receptor numbers and receptor regulation by guanine nucleotides are maintained in suspension-grown cells, the inhibition of adenylate cyclase by the 5-HT1A receptor is gradually lost. Images Fig. 1. PMID:1386736

  10. Dopaminergic neurons modulate GABA neuron migration in the embryonic midbrain

    PubMed Central

    Vasudevan, Anju; Won, Chungkil; Li, Suyan; Erdélyi, Ferenc; Szabó, Gábor; Kim, Kwang-Soo

    2012-01-01

    Neuronal migration, a key event during brain development, remains largely unexplored in the mesencephalon, where dopaminergic (DA) and GABA neurons constitute two major neuronal populations. Here we study the migrational trajectories of DA and GABA neurons and show that they occupy ventral mesencephalic territory in a temporally and spatially specific manner. Our results from the Pitx3-deficient aphakia mouse suggest that pre-existing DA neurons modulate GABA neuronal migration to their final destination, providing novel insights and fresh perspectives concerning neuronal migration and connectivity in the mesencephalon in normal as well as diseased brains. PMID:22872083

  11. Dopaminergic neurons modulate GABA neuron migration in the embryonic midbrain.

    PubMed

    Vasudevan, Anju; Won, Chungkil; Li, Suyan; Erdélyi, Ferenc; Szabó, Gábor; Kim, Kwang-Soo

    2012-09-01

    Neuronal migration, a key event during brain development, remains largely unexplored in the mesencephalon, where dopaminergic (DA) and GABA neurons constitute two major neuronal populations. Here we study the migrational trajectories of DA and GABA neurons and show that they occupy ventral mesencephalic territory in a temporally and spatially specific manner. Our results from the Pitx3-deficient aphakia mouse suggest that pre-existing DA neurons modulate GABA neuronal migration to their final destination, providing novel insights and fresh perspectives concerning neuronal migration and connectivity in the mesencephalon in normal as well as diseased brains.

  12. Selective blockade of 5-hydroxytryptamine (5-HT)7 receptors enhances 5-HT transmission, antidepressant-like behavior, and rapid eye movement sleep suppression induced by citalopram in rodents.

    PubMed

    Bonaventure, Pascal; Kelly, Lisa; Aluisio, Leah; Shelton, Jonathan; Lord, Brian; Galici, Ruggero; Miller, Kirsten; Atack, John; Lovenberg, Timothy W; Dugovic, Christine

    2007-05-01

    Evidence has accumulated supporting a role for 5-hydroxytryptamine (5-HT)7 receptors in circadian rhythms, sleep, and mood disorders, presumably as a consequence of the modulation of 5-HT-mediated neuronal activity. We hypothesized that a selective 5-HT7 receptor antagonist, (2R)-1-[(3-hydroxyphenyl)sulfonyl]-2-[2-(4-methyl-1-piperidinyl)ethyl]-pyrrolidine (SB-269970), should increase activity of 5-HT neurons and potentiate the effect of selective serotonin reuptake inhibitors (citalopram). In rats, administration of 3 mg/kg s.c. citalopram alone increased the extracellular concentration of 5-HT. This effect of citalopram on extracellular 5-HT concentration was significantly enhanced by an ineffective dose of SB-269970. Combining this dose of SB-269970 with a low dose of citalopram also resulted in a significant increase in extracellular concentration of 5-HT, suggesting a potentiation of neurochemical effects. In mice, citalopram and SB-269970 dose-dependently decreased immobility time in the tail suspension test. The dose-effect curve of citalopram was shifted leftward by coadministration of an effective dose of SB-269970. Furthermore, combining ineffective doses of citalopram and SB-269970 also resulted in a significant decrease of immobility time in the tail suspension test, suggesting potentiation of antidepressant-like effects. In rats, SB-269970 potentiated the increase of rapid eye movement (REM) latency and the REM sleep decrease induced by citalopram. SB-269970 also reversed the increase in sleep fragmentation induced by citalopram. Rat plasma and brain concentrations of citalopram were not affected by coadministration of SB-269970, arguing for a pharmacodynamic rather than a pharmacokinetic mechanism. Overall, these results indicate that selective blockade of 5-HT7 receptors may enhance the antidepressant efficacy of citalopram and may provide a novel therapy to alleviate sleep disturbances associated with depression.

  13. AMPA receptor involvement in 5-hydroxytryptamine2A receptor-mediated pre-frontal cortical excitatory synaptic currents and DOI-induced head shakes.

    PubMed

    Zhang, Ce; Marek, Gerard J

    2008-01-01

    Glutamate plays an important role in the psychotomimetic effects of both channel blocking N-methyl D-aspartate (NMDA) receptor antagonists and hallucinogenic drugs which activate 5-hydroxytryptamine2A (5-HT2A) receptors. Previous work suggested that activation of non-NMDA ionotropic glutamate receptors mediates the effects of 5-HT-induced excitatory post-synaptic potentials/currents (EPSPs/EPSCs) when recording from layer V pyramidal cells in the rat medial pre-frontal cortex (mPFC). However, those effects are mediated by either alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) or kainate receptors of the iGluk5 subtype. To test whether activation of AMPA receptors is sufficient to mediate 5-HT-induced EPSCs, a 2,3-benzodiazepine that selectively blocks AMPA receptors was assessed. This selective AMPA receptor antagonist potently suppressed 5-HT-induced EPSCs. Since phenethylamine hallucinogens induce head shakes by activating 5-HT2A receptors in the mPFC and this action is modulated by glutamate, we also examined whether selective blockade of AMPA receptors would suppress DOI-induced head shakes. As predicted, we found that selective blockade of AMPA receptors suppressed DOI-induced head shakes. Given evidence that activation of AMPA receptors is an important downstream effect for both channel blocking NMDA receptor antagonists and phenethylamine hallucinogens, we also tested multiple doses of DOI with a sub-anesthetic dose of MK-801. Synergistic action between these two classes of psychotomimetic drugs was demonstrated by MK-801 enhancing DOI-induced head shakes and locomotor activity. These findings expand the dependence of both channel blocking NMDA receptor antagonists and phenethylamine hallucinogens on enhancing extracellular glutamate.

  14. Effects of 5-hydroxytryptamine, dopamine, and acetylcholine on accumulation of cyclic AMP and cyclic GMP in the anterior byssus retractor muscle of Mytilus edulis L. (Mollusca).

    PubMed

    Köhler, G; Lindl, T

    1980-02-01

    We investigated in vitro accumulation of adenosine 3',5'-monophosphate (induced by 5-hydroxytryptamine and dopamine) and of guanosine 3',5'-monophosphate (induced by acetylcholine) in the anterior byssus retractor muscle of Mytilus. The response to 5-hydroxytryptamine exceeded that induced by equimolar concentrations of dopamine. 1-methyl lysergic acid, a 5-hydroxytryptamine-blocking agent, diminished the 5-hydroxytryptamine-induced increase of cyclic AMP level. This parallels the effect of this amine on the contracted muscle. Acetylcholine, which causes a tonic contraction of the muscle, increased intracellular levels of cyclic GMP in a dose-dependent (max. 45-fold at 10(-4) M ACh) manner. The time course of the rise in cyclic GMP level was rapid and transient (peak concentration of cyclic GMP at 2 min). Mytolon was the most effective of all cholinergic blockers tested. It was concluded that cyclic nucleotides may play a role in the modulatory process of the transmitters. A direct relation to the relaxation-contraction process could not be established.

  15. A randomized trial of 5-hydroxytryptamine4-receptor agonist, YKP10811, on colonic transit and bowel function in functional constipation.

    PubMed

    Shin, Andrea; Acosta, Andres; Camilleri, Michael; Boldingh, Amy; Burton, Duane; Ryks, Michael; Rhoten, Deborah; Zinsmeister, Alan R

    2015-04-01

    YKP10811, a selective agonist of the serotonin 5-hydroxytryptamine-4 receptor, increases gastrointestinal (GI) motility. We investigated the safety and effects of YKP10811 on GI and colonic transit and bowel movements (BMs) in patients with functional constipation in a randomized, double-blind, placebo-controlled study. Patients with functional constipation, based on the Rome III criteria, were assigned randomly to groups given YKP10811 10 mg (n = 15), 20 mg (n = 16), 30 mg (n = 15), or placebo (n = 11) daily for 8 days. Transit of solids was measured by validated scintigraphy at baseline and on days 7 to 9. Patients kept diaries on days 1 to 9, recording time to first BM, number of BMs/day, and stool consistency (based on the Bristol Stool Form Scale). To evaluate safety, we collected data on adverse events and clinical laboratory test and electrocardiograms results. The primary efficacy end points were determined from an intent-to-treat analysis assessing colonic transit at 24 hours and the half-time (t1/2) of gastric emptying, using analysis of covariance models. Secondary efficacy end points included measures of colonic transit (geometric center at 4 and 24 hours), small-bowel transit (based on colon filling at 6 hours), t1/2 of ascending colon emptying, and bowel functions. We used the Dunnett test to compare the effects of each dose with placebo. A per-protocol analysis (PPA) assessed the t1/2 of gastric emptying and time to first BM using proportional hazards models. Fifty-five participants completed the study. YKP10811 was associated with a significant acceleration in colon filling at 6 hours (P < .05), t1/2 of ascending colon emptying, and colonic transit at 24 and 48 hours, as well as increased stool consistency over 8 days (based on intent-to-treat analysis). In general, the 10-mg and 20-mg doses were the most effective in accelerating colonic transit. No serious adverse events were observed. YKP10811, a selective agonist of the serotonin receptor 5

  16. Effects of procaine and extracellular calcium concentration on response of rat stomach fundus muscle to acetylcholine and 5-hydroxytryptamine.

    PubMed Central

    Weinstock, M; Weiss, C

    1979-01-01

    1. When rat stomach fundus muscle was incubated for 30 min in Tyrode solution from which calcium chloride had been omitted, there was an almost complete abolition of the contractile response to 5-hydroxytryptamine (5-HT) while that to acetylcholine (ACh) was still present. 2. The maximum tension obtainable with ACh remained the same in external calcium concentrations ranging from 0.45 to 3.6 mM, but the pD2 value increased. 3. A concentration of at least 0.9 mM calcium was needed to maintain a maximum contraction with 5-HT, and the pD2 for this agent also increased significantly with increase in calcium content of the medium. 4. The effects of procaine on the responses of the muscle to 5-HT and ACh were similar to the respective changes induced by lowering the calcium concentration, and were reduced by the addition of calcium. 5. Concentrations of 2.2 x 10(-7) to 3.6 x 10(-5) M procaine reduced the effects of both 5-HT and KCl and suppressed the maximum responses. 6. The maximum responses to KCl and 5-HT were restored at higher concentrations of procaine (greater than 3.6 x 10(-4) M), while the effect of ACh was reduced. 7. It is suggested that 5-HT, like KCl, is almost entirely dependent on extracellular calcium for inducing muscle contraction, while ACh may utilize calcium from bound stores. PMID:435684

  17. 6-Substituted tricyclic partial ergoline compounds are selective and potent 5-hydroxytryptamine sub 1A receptor agents

    SciTech Connect

    Slaughter, J.L.; Harrington, M.A.; Peroutka, S.J. )

    1990-01-01

    A series of 6 tricyclic partial ergoline derivatives was analyzed using radioligand binding assays. Four agents (LY 178210, LY 254089, LY 197205, and LY 197206) display high affinity for 5-hydroxytryptamine{sub 1A} (5-HT{sub 1A}) receptor binding sites labeled by ({sup 3}H)8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) and display {ge} 150 fold selectivity for the 5-HT{sub 1A} over the 5-HT{sub 1D} receptor binding site. The most potent agent investigated, LY 178210, is essentially inactive at a total of 12 other neurotransmitter receptor binding sites in the brain. Using a forskolin-stimulated adenylate cyclase assay as a model of 5-HT{sub 1A} receptor function, LY 178210 was found to display partial agonist activity which was blocked by 10{sup {minus}5} M ({minus})pindolol. These data indicate that LY 178210 is a potent and selective 5-HT{sub 1A} receptor partial agonist.

  18. Effects of morphine, physostigmine and raphe nuclei stimulation on 5-hydroxytryptamine release from the cerebral cortex of the cat.

    PubMed Central

    Aiello-Malmberg, P; Bartolini, A; Bartolini, R; Galli, A

    1979-01-01

    1. The release of 5-hydroxytryptamine (5-HT) from the cerebral cortex and caudate nucleus of brainstem-transected cats and from the cerebral cortex of rats anaesthetized with urethane was determined by radioenzymatic and biological assay. 2. The stimulation of nucleus linearis intermedius of raphe doubles the basal 5-HT release in the caudate nucleus and increases it 3 fold in the cerebral cortex. The effects of the electrical stimulation of the raphe are potentiated by chlorimipramine. 3. Brain 5-HT release is greatly increased by morphine hydrochloride (6 mg/kg i.v.) and by physostigmine (100 microgram/kg i.v.), but not by DL-DOPA (50 mg/kg i.v.). 4. It is suggested that the 5-HT releasing action of physostigmine can contribute to some of its pharmacological effects such as the analgesic effect so far attributed exclusively to its indirect cholinomimetic activity. 5. The 5-HT releasing action of physostigmine seems unrelated to its anticholinesterase activity. PMID:435680

  19. Mediation of 5-hydroxytryptamine-induced tachycardia in the pig by the putative 5-HT4 receptor.

    PubMed Central

    Villalón, C. M.; den Boer, M. O.; Heiligers, J. P.; Saxena, P. R.

    1990-01-01

    Intravenous bolus injections of 5-hydroxytryptamine (5-HT; 3, 10 and 30 micrograms kg-1), 5-methoxytryptamine (5-MeO-T; 3, 10 and 30 micrograms kg-1), renzapride (BRL 24924; 3, 10, 30 and 100 micrograms kg-1) and isoprenaline (0.03, 0.1 and 0.3 micrograms kg-1) to anaesthetized pigs increased heart rate by, respectively, 22 +/- 3, 44 +/- 3 and 65 +/- 4 beats min-1 (5-HT; n = 17); 12 +/- 1, 26 +/- 2 and 44 +/- 4 beats min-1 (5-MeO-T; n = 15), 5 +/- 2, 11 +/- 2, 18 +/- 4 and 37 +/- 5 beats min-1 (renzapride; n = 8) and 17 +/- 2, 46 +/- 3 and 75 +/- 3 beats min-1 (isoprenaline; n = 13). The responses to 5-HT, 5-MeO-T and renzapride were antagonized by ICS 205-930 (1 and 3 mg kg-1, i.v.), which did not modify the increases in heart rate by isoprenaline. Renzapride showed tachyphylaxis and attenuated the responses to 5-HT. These findings indicate that 5-HT elicits tachycardia in the pig by acting on a novel receptor, either similar or identical to the 5-HT4 receptor identified in mouse brain colliculi. PMID:2207493

  20. Serotonin (5-hydroxytryptamine, 5-HT) immunoreactive endocrine and neural elements in the chromaffin enteropancreatic system of amphibians and reptiles.

    PubMed

    Trandaburu, Tiberiu; Trandaburu, Ioana

    2007-01-01

    The diffuse chromaffin enteropancreatic system of nine species of amphibians (newts, frogs) and reptiles (turtles, lizards, snakes) was investigated immunohistochemically for the presence and topographic distribution of serotonin (5-hydroxytryptamine, 5-HT). The study revealed various numbers of serotonin-producing cells in the pancreas and intestinal epithelium and also immunolabelled nerve profiles in the villi of all species studied. In addition, two different morphological populations of serotonin cells ("open" and "closed") were localized in the functional segments of the intestines in the representative species of all the taxa investigated. Semi-quantitative evaluation of the immunolabelled pancreatic and enteric cells revealed significantly different mean numbers of labelled cells in different amphibian and reptilian taxa, and also between the various successive gut segments of each taxon. The ratio between "open" and "closed" varieties of serotonin cells recorded along the intestines followed a decreasing trend, progressive in lizards and snakes and more abrupt in newts, frogs and turtles. The above findings may help resolve several key stages of the phylogenetic evolution of poikilothermic vertebrates.

  1. Kinetic definition of agonist efficacy at a 5-hydroxytryptamine (5-HT2) receptor in the isolated rabbit aorta.

    PubMed

    Cory, R N; Osman, R; Maayani, S

    1986-01-01

    The contractile response of the isolated rabbit aorta elicited by 5-hydroxytryptamine (5-HT) and five partial agonists acting on the 5-HT2 receptor were separated into a phasic and a tonic response by altering the [Ca++] in the buffer. A kinetic analysis of the two responses yields parameters that provide a mechanistic insight into the different nature of these responses. The kinetic parameters of the phasic contraction indicate that the onset of this response depends on the access of the drug to the receptor and that its decay is independent of the nature and the concentration of the agonist. The observed rate constant of the onset of the tonic response, kobs, is saturable with increasing drug concentration, suggesting that the rate determining step is the activation of an effector by the preformed drug-receptor complex. These kinetic characteristics of the 5-HT2-mediated response are similar to those observed previously by us for the alpha-1 adrenergic receptor-mediated response in the rabbit aorta, suggesting that these receptors activate similar mechanisms related to the mobilization of Ca++. Furthermore, it is shown that the maximal values of kobs for the 5-HT2 agonists follow the rank order of maximal amplitudes of the phasic responses and the maximal steady-state levels of the tonic response. It is suggested that the maximal value of kobs may serve as a kinetic measure of drug efficacy.

  2. 5-Carboxamidotryptamine is a selective agonist at 5-hydroxytryptamine receptors mediating vasodilatation and tachycardia in anaesthetized cats.

    PubMed Central

    Connor, H. E.; Feniuk, W.; Humphrey, P. P.; Perren, M. J.

    1986-01-01

    We have attempted to characterize the 5-hydroxytryptamine (5-HT) receptors mediating bronchoconstriction, vasodilatation, vasodepression and tachycardia in anaesthetized cats following bilateral vagosympathectomy and beta-adrenoceptor blockade with propranolol. 5-HT (1-100 micrograms/kg-1 i.v.) caused dose-related bronchoconstriction and tachycardia but variable and complex effects on diastolic blood pressure and carotid arterial vascular resistance. In contrast, 5-carboxamidotryptamine (5-CT; 0.01-1 micrograms kg-1 i.v.) caused consistent, dose-related decreases in diastolic blood pressure and carotid arterial vascular resistance and increases in heart rate. 5-CT did not cause bronchoconstriction. The 5-HT-induced bronchoconstriction was dose-dependently antagonized by methiothepin, methysergide and ketanserin (10-100 micrograms kg-1 i.v.). The highest doses used of these antagonists did not antagonize bronchoconstriction induced by prostaglandin F2 alpha. The high potency of all three antagonists indicate a 5-HT2-receptor mediated effect. The 5-HT- and 5-CT-induced tachycardia as well as the 5-CT-induced vasodepressor and carotid arterial vasodilator responses were dose-dependently antagonized by low doses of methiothepin (10-100 micrograms kg-1 i.v.) and by high doses of methysergide (100-1000 micrograms kg-1 i.v.) but were little affected by ketanserin in doses up to 1000 micrograms kg-1 i.v. These selective effects of 5-CT appear to be mediated by '5-HT1-like' receptors. PMID:2937503

  3. Comparative effects of niflumic acid and nifedipine on 5-hydroxytryptamine- and acetylcholine-induced contraction of the rat trachea.

    PubMed

    Teixeira, M C; Coelho, R R; Leal-Cardoso, J H; Criddle, D N

    2000-04-07

    The effects of niflumic acid, an inhibitor of Ca(2+)-activated Cl(-) (Cl((Ca))) channels, were compared with those of the voltage-dependent Ca(2+) channel (VDCC) blocker nifedipine on 5-hydroxytryptamine (5-HT)- and acetylcholine-induced contractions of the rat isolated trachea. Niflumic acid (3-100 microM) induced a concentration-dependent inhibition of 5-HT (10 microM)-induced contractions, with a reduction to 37.0+/-9.5% of the control at the highest concentration. One micromolar nifedipine, which completely blocked 60 mM KCl-induced contractions, reduced the response to 5-HT similarly to 39.2+/-11.5% of the control. The inhibition of the 5-HT response was not significantly different from that produced by the combined presence of nifedipine (1 microM) and niflumic acid (100 microM), suggesting that their effects were not additive. In contrast, neither niflumic acid (3-100 microM) nor nifedipine (1 microM) inhibited acetylcholine-induced contractions. The contraction to 5-HT (10 microM) in Cl(-)-free solution was decreased by more than approximately 85% of the control, whilst that of acetylcholine was reduced only by approximately 36%. Our data show that niflumic acid exerts selective inhibitory effects on 5-HT-induced contraction, and suggest that activation of Cl((Ca)) channels may be a mechanism whereby 5-HT (but not acetylcholine) induces Ca(2+) entry via VDCCs to elicit contraction.

  4. Superagonist, Full Agonist, Partial Agonist, and Antagonist Actions of Arylguanidines at 5-Hydroxytryptamine-3 (5-HT3) Subunit A Receptors.

    PubMed

    Alix, Katie; Khatri, Shailesh; Mosier, Philip D; Casterlow, Samantha; Yan, Dong; Nyce, Heather L; White, Michael M; Schulte, Marvin K; Dukat, Małgorzata

    2016-11-16

    Introduction of minor variations to the substitution pattern of arylguanidine 5-hydroxytryptamine-3 (5-HT3) receptor ligands resulted in a broad spectrum of functionally-active ligands from antagonist to superagonist. For example, (i) introduction of an additional Cl-substituent(s) to our lead full agonist N-(3-chlorophenyl)guanidine (mCPG, 2; efficacy % = 106) yielded superagonists 7-9 (efficacy % = 186, 139, and 129, respectively), (ii) a positional isomer of 2, p-Cl analog 11, displayed partial agonist actions (efficacy % = 12), and (iii) replacing the halogen atom at the meta or para position with an electron donating OCH3 group or a stronger electron withdrawing (i.e., CF3) group resulted in antagonists 13-16. We posit based on combined mutagenesis, crystallographic, and computational analyses that for the 5-HT3 receptor, the arylguanidines that are better able to simultaneously engage the primary and complementary subunits, thus keeping them in close proximity, have greater agonist character while those that are deficient in this ability are antagonists.

  5. 5-Hydroxytryptamine (5-HT) Cellular Sequestration during Chronic Exposure Delays 5-HT3 Receptor Resensitization due to Its Subsequent Release*

    PubMed Central

    Hothersall, J. Daniel; Alexander, Amy; Samson, Andrew J.; Moffat, Christopher; Bollan, Karen A.; Connolly, Christopher N.

    2014-01-01

    The serotonergic synapse is dynamically regulated by serotonin (5-hydroxytryptamine (5-HT)) with elevated levels leading to the down-regulation of the serotonin transporter and a variety of 5-HT receptors, including the 5-HT type-3 (5-HT3) receptors. We report that recombinantly expressed 5-HT3 receptor binding sites are reduced by chronic exposure to 5-HT (IC50 of 154.0 ± 45.7 μm, t½ = 28.6 min). This is confirmed for 5-HT3 receptor-induced contractions in the guinea pig ileum, which are down-regulated after chronic, but not acute, exposure to 5-HT. The loss of receptor function does not involve endocytosis, and surface receptor levels are unaltered. The rate and extent of down-regulation is potentiated by serotonin transporter function (IC50 of 2.3 ± 1.0 μm, t½ = 3.4 min). Interestingly, the level of 5-HT uptake correlates with the extent of down-regulation. Using TX-114 extraction, we find that accumulated 5-HT remains soluble and not membrane-bound. This cytoplasmically sequestered 5-HT is readily releasable from both COS-7 cells and the guinea pig ileum. Moreover, the 5-HT level released is sufficient to prevent recovery from receptor desensitization in the guinea pig ileum. Together, these findings suggest the existence of a novel mechanism of down-regulation where the chronic release of sequestered 5-HT prolongs receptor desensitization. PMID:25281748

  6. Pharmacological properties of 403U76, a new chemical class of 5-hydroxytryptamine- and noradrenaline-reuptake inhibitor.

    PubMed

    Ferris, R M; Brieaddy, L; Mehta, N; Hollingsworth, E; Rigdon, G; Wang, C; Soroko, F; Wastila, W; Cooper, B

    1995-09-01

    403U76 (5-chloro-[[2-[(dimethylamino)methyl]phenyl]thio]benzene- methanol hydrochloride) is a potent, competitive, inhibitor of 5-hydroxytryptamine (5-HT) and noradenaline reuptake into rat brain synaptosomes. Inhibition of 5-HT uptake in-vivo by 403U76 was demonstrated by potentiation of the behavioural effects of 5-hydroxytryptophan in rats and mice and blockade of p-induced depletion of 5-HT in rats. The firing of 5-HT-ergic dorsal raphe neurons in rats was decreased after intravenous administration of low doses of 403U76 as would be predicted for a 5-HT uptake inhibitor. 403U76 antagonized tetrabenazine-induced sedation, an effect associated with inhibitors of noradrenaline uptake, but not with inhibitors of 5-HT uptake. Thus 403U76 affects noradrenergic as well as 5-HT-ergic neurotransmission in-vivo. Potential anxiolytic activity was indicated by reductions in isolation-induced vocalizations in neonates after 403U76 treatment. Low intravenous doses of 403U76 were well tolerated and had no sustained cardiovascular effects. There were no deleterious behavioural side-effects at active doses. Effects observed on isolated tissues or transmitter receptors occurred only at very high concentrations and were pharmacologically unimportant. Thus 403U76 can be considered a potential antidepressant/anxiolytic agent that is a potent, selective inhibitor of 5-HT and noradrenaline reuptake.

  7. Identification of 5-Hydroxytryptamine-Producing Cells by Detection of Fluorescence in Paraffin-Embedded Tissue Sections

    PubMed Central

    Kaneko, Y.; Onda, N.; Watanabe, Y.; Shibutani, M.

    2016-01-01

    5-Hydroxytryptamine (5-HT) produced by enterochromaffin (EC) cells is an important enteric mucosal signaling ligand and has been implicated in several gastrointestinal diseases, including inflammatory bowel disease and functional disorders such as irritable bowel syndrome. The present study reports a new, simple and rapid visualization method of 5-HT-producing EC cells utilizing detection of fluorescence in paraffin-embedded tissue sections after formalin fixation. In human samples, there was a high incidence of fluorescence+ cells in the 5-HT+ cells in the pyloric, small intestinal and colonic glands, while co-localization was lacking between fluorescence+ and gastrin+ cells in the pyloric and small intestinal glands. Fluorescence+ EC cells were detected in the colon of mice and rats. Fluorescence+ cells were also observed in 5-HT+ β cells in the pancreatic islets of Langerhans in pregnant mice, while non-pregnant mouse pancreatic islet cells showed no 5-HT immunoreactivity or fluorescence. These results suggest that fluorescence+ cells are identical to 5-HT+ cells, and the source of fluorescence may be 5-HT itself or molecules related to its synthesis or degradation. This fluorescence signal detection method may be applicable for monitoring of inflammatory status of inflammatory bowel diseases in both the experimental and clinical settings. PMID:27734992

  8. Identification and characterization of a truncated variant of the 5-hydroxytryptamine(2A) receptor produced by alternative splicing.

    PubMed

    Guest, P C; Salim, K; Skynner, H A; George, S E; Bresnick, J N; McAllister, G

    2000-09-08

    We have identified an alternatively spliced 5-hydroxytryptamine 2A receptor (5-HT(2A)-R) transcript by PCR of human brain cDNA using degenerate oligonucleotide primers to transmembrane (TM) domains 3 and 7 of the 5-HT(2)-R subfamily. The variant contains a 118-bp insertion at the exon II/III boundary of the 5-HT(2A)-R, which produces a frame shift in the coding sequence and a premature stop codon. PCR analysis showed that the truncated receptor (5-HT(2A-tr)) and native 5-HT(2A)-R were co-expressed in most brain tissues, with the highest levels being found in hippocampus, corpus collosum, amygdala and caudate nucleus. Western blot analysis of HEK-293 cells transfected transiently with a 5-HT(2A-tr) construct showed that a 30-kDa protein was expressed on cell membranes. Co-transfection studies showed no effect of the 5-HT(2A-tr) variant on 3H-ketanserin binding to the native 5-HT(2A)-R or on functional coupling of the 5-HT(2A)-R to 5-HT-stimulated Ca(2+) mobilization. The functional significance of the 5-HT(2A-tr) variant and other truncated receptors remains to be established.

  9. Quercetin inhibits the 5-hydroxytryptamine type 3 receptor-mediated ion current by interacting with pre-transmembrane domain I.

    PubMed

    Lee, Byung-Hwan; Jeong, Sang-Min; Jung, Sang-Min; Lee, Jun-Ho; Kim, Jong-Hoon; Yoon, In-Soo; Lee, Joon-Hee; Choi, Sun-Hye; Lee, Sang-Mok; Chang, Choon-Gon; Kim, Hyung-Chun; Han, YeSun; Paik, Hyun-Dong; Kim, Yangmee; Nah, Seung-Yeol

    2005-08-31

    The flavonoid, quercetin, is a low molecular weight substance found in apple, tomato and other fruit. Besides its antioxidative effect, quercetin, like other flavonoids, has a wide range of neuropharmacological actions including analgesia, and motility, sleep, anticonvulsant, sedative and anxiolytic effects. In the present study, we investigated its effect on mouse 5-hydroxytryptamine type 3 (5-HT3A) receptor channel activity, which is involved in pain transmission, analgesia, vomiting, and mood disorders. The 5-HT3A receptor was expressed in Xenopus oocytes, and the current was measured with the two-electrode voltage clamp technique. In oocytes injected with 5-HT3A receptor cRNA, quercetin inhibited the 5-HT-induced inward peak current (I(5-HT)) with an IC50 of 64.7 +/- 2.2 microM. Inhibition was competitive and voltage-independent. Point mutations of pre-transmembrane domain 1 (pre-TM1) such as R222T and R222A, but not R222D, R222E and R222K, abolished inhibition, indicating that quercetin interacts with the pre-TM1 of the 5-HT3A receptor.

  10. Release of endogenous 5-hydroxytryptamine from the myenteric plexus of the guinea-pig isolated small intestine.

    PubMed Central

    Holzer, P.; Skofitsch, G.

    1984-01-01

    The presence of 5-hydroxytryptamine (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in, and the release of these substances from, the myenteric plexus-longitudinal muscle (MPLM) layer of the guinea-pig isolated small intestine were investigated. 5-HT and 5-HIAA were measured by high performance liquid chromatography and electrochemical detection. Freshly prepared MPLM contained measurable amounts of 5-HT and 5-HIAA. For the release experiments, the MPLM was incubated in a medium containing the 5-HT uptake inhibitor fluoxetine and the monoamine oxidase inhibitor nialamide; this led to a decrease in the 5-HIAA content of the MPLM whereas the 5-HT content remained unchanged. There was a spontaneous release of 5-HT and 5-HIAA from the MPLM. The release of 5-HT was so small that it was just detectable; it seemed equivalent to about 0.8% of the tissue stores released per min. Depolarization of the tissue by increasing the [K+] or by exposing it to veratridine enhanced the release of 5-HT in a Ca2+-dependent manner whereas the release of 5-HIAA was not increased. Tetrodotoxin inhibited the veratridine-evoked release of 5-HT but did not affect the K+-evoked release of 5-HT. The presence of 5-HT in myenteric neurones and the characteristics of the release of 5-HT from these neurones strongly support the hypothesis that 5-HT is an enteric neurotransmitter. PMID:6200171

  11. Action of angiotensin II, 5-hydroxytryptamine and adenosine triphosphate on ionic currents in single ear artery cells of the rabbit.

    PubMed

    Hughes, A D; Bolton, T B

    1995-10-01

    1. Angiotensin II, 5-hydroxytryptamine (5-HT) and adenosine triphosphate (ATP) evoked a transient inward current in isolated single car artery cells of rabbit held at -60 mV by whole cell voltage clamp in physiological saline using a KCL-containing pipette solution. Under these conditions agonist did not activate a calcium-dependent potassium current. 2. Responses to each agonist were transient and desensitized rapidly. Inward current at -60 mV holding potential was not abolished by blockade of voltage-dependent calcium channels or by buffering intracellular calcium with BAPTA, a calcium chelator, or following depletion of intracellular calcium stores with ryanodine. 3. The shape of the current-voltage relationships and the reversal potentials of the current induced by angiotensin II, 5-HT and ATP were similar under a variety of ionic conditions. Agonist-induced current was unaffected by replacing intracellular chloride with citrate ions or by replacing intracellular sodium with caesium or extracellular sodium with barium or calcium. Replacement of extracellular sodium with Tris shifted the reversal potential in all cases by around 30 mV negatively. 4. These data suggest that angiotensin II, 5-HT and ATP activate similar cationic conductances which are relatively non-selective allowing mono- and divalent cations to cross the smooth muscle cell membrane. These channels may allow the influx of calcium under physiological conditions.

  12. A noncanonical release of GABA and glutamate modulates neuronal migration.

    PubMed

    Manent, Jean-Bernard; Demarque, Michaël; Jorquera, Isabel; Pellegrino, Christophe; Ben-Ari, Yehezkel; Aniksztejn, Laurent; Represa, Alfonso

    2005-05-11

    Immature neurons express GABA and glutamate receptors before synapse formation, and both transmitters are released at an early developmental stage. We have now tested the hypothesis that the ongoing release of GABA and glutamate modulates neuronal migration. Using 5-bromo-2'-deoxyuridine labeling and cocultures of hippocampal slices obtained from naive and green fluorescent protein-transgenic mice, we report that migration is severely affected by GABA(A) or NMDA receptor antagonist treatments. These effects were also present in munc18-1 knock-out slices in which soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE)-dependent vesicular secretion of transmitters has been deleted. GABA(A) antagonists were more efficient than NMDA antagonists to reduce cell migration, in keeping with the earlier maturation of GABAergic mechanisms. We conclude that GABA and, to a lesser degree, glutamate released in a SNARE-independent mechanism exert a paracrine action on neuronal migration.

  13. Effect of nitroglycerine in popliteal preparations from patients with peripheral occlusive arteriopathy precontracted with KCl or 5-hydroxytryptamine.

    PubMed

    Ortega, Ana; Avellanal, Martin; España, Gabriel; Flores, Angel; Aleixandre, Amaya

    2003-08-01

    1. At the present time, there are no studies in isolated arteries from patients suffering from peripheral occlusive arteriopathy (POA). In the present study, we attempt to characterize the effect of nitroglycerine (GTN) in isolated popliteal preparations obtained after leg amputation in 60-90-year-old men and women suffering from POA. 2. After surgical operation, arterial samples were stored in a refrigerator at 4 degrees C and, after 12-36 h, they were cut into rings and mounted in organ baths containing Krebs'-Henseleit solution at 37 degrees C and gassed constantly with 95% CO2 and 5% O2. Because noradrenaline elicited very poor contractile responses in these preparations, in the present study we evaluated the concentration-dependent contractions induced by KCl (15-90 mmol/L) and 5-hydroxytryptamine (5-HT; 10-7 to 10-4 mol/L) in arteriopathic popliteal rings and, when the corresponding maximum contractile effect had been obtained, we also evaluated the concentration-dependent relaxing effect produced by GTN (10-10 to 10-5 mol/L) in all precontracted preparations. As a reference, similar experiments were performed in popliteal preparations obtained following surgery on non-arteriopathic vascular tissue where it was necessary to resect a certain percentage of healthy vessel. 3. The responses to KCl and 5-HT were greater in healthy vessel than in arteriopathic rings. The relaxing effect of GTN was greater in preparations precontracted with 5-HT than in those preparations precontracted with KCl. In addition, preparations precontracted with KCl relaxed even less when they were obtained from patients with POA. 4. The present data indicate that GTN is a vasodilator with little effect on depolarized arteries. The results also indicate that the effect of this drug is even less in depolarized arteries from patients with POA.

  14. 5-hydroxytryptamine (5-HT) reduces total peripheral resistance during chronic infusion: direct arterial mesenteric relaxation is not involved

    PubMed Central

    2012-01-01

    Serotonin (5-hydroxytryptamine; 5-HT) delivered over 1 week results in a sustained fall in blood pressure in the sham and deoxycorticosterone acetate (DOCA)-salt rat. We hypothesized 5-HT lowers blood pressure through direct receptor-mediated vascular relaxation. In vivo, 5-HT reduced mean arterial pressure (MAP), increased heart rate, stroke volume, cardiac index, and reduced total peripheral resistance during a 1 week infusion of 5-HT (25 µg/kg/min) in the normotensive Sprague Dawley rat. The mesenteric vasculature was chosen as an ideal candidate for the site of 5-HT receptor mediated vascular relaxation given the high percentage of cardiac output the site receives. Real-time RT-PCR demonstrated that mRNA transcripts for the 5-HT2B, 5-HT1B, and 5-HT7 receptors are present in sham and DOCA-salt superior mesenteric arteries. Immunohistochemistry and Western blot validated the presence of the 5-HT2B, 5- HT1B and 5-HT7 receptor protein in sham and DOCA-salt superior mesenteric artery. Isometric contractile force was measured in endothelium-intact superior mesenteric artery and mesenteric resistance arteries in which the contractile 5- HT2A receptor was antagonized. Maximum concentrations of BW-723C86 (5- HT2B agonist), CP 93129 (5-HT1B agonist) or LP-44 (5-HT7 agonist) did not relax the superior mesenteric artery from DOCA-salt rats vs. vehicle. Additionally, 5-HT (10–9 M to 10–5 M) did not cause relaxation in either contracted mesenteric resistance arteries or superior mesenteric arteries from normotensive Sprague- Dawley rats. Thus, although 5-HT receptors known to mediate vascular relaxation are present in the superior mesenteric artery, they are not functional, and are therefore not likely involved in a 5-HT-induced fall in total peripheral resistance and MAP. PMID:22559843

  15. 5-hydroxytryptamine (5-HT) reduces total peripheral resistance during chronic infusion: direct arterial mesenteric relaxation is not involved.

    PubMed

    Davis, Robert Patrick; Pattison, Jill; Thompson, Janice M; Tiniakov, Ruslan; Scrogin, Karie E; Watts, Stephanie W

    2012-05-06

    Serotonin (5-hydroxytryptamine; 5-HT) delivered over 1 week results in a sustained fall in blood pressure in the sham and deoxycorticosterone acetate (DOCA)-salt rat. We hypothesized 5-HT lowers blood pressure through direct receptor-mediated vascular relaxation. In vivo, 5-HT reduced mean arterial pressure (MAP), increased heart rate, stroke volume, cardiac index, and reduced total peripheral resistance during a 1 week infusion of 5-HT (25 µg/kg/min) in the normotensive Sprague Dawley rat. The mesenteric vasculature was chosen as an ideal candidate for the site of 5-HT receptor mediated vascular relaxation given the high percentage of cardiac output the site receives. Real-time RT-PCR demonstrated that mRNA transcripts for the 5-HT2B, 5-HT1B, and 5-HT7 receptors are present in sham and DOCA-salt superior mesenteric arteries. Immunohistochemistry and Western blot validated the presence of the 5-HT2B, 5- HT1B and 5-HT7 receptor protein in sham and DOCA-salt superior mesenteric artery. Isometric contractile force was measured in endothelium-intact superior mesenteric artery and mesenteric resistance arteries in which the contractile 5- HT2A receptor was antagonized. Maximum concentrations of BW-723C86 (5- HT2B agonist), CP 93129 (5-HT1B agonist) or LP-44 (5-HT7 agonist) did not relax the superior mesenteric artery from DOCA-salt rats vs. vehicle. Additionally, 5-HT (10-9 M to 10-5 M) did not cause relaxation in either contracted mesenteric resistance arteries or superior mesenteric arteries from normotensive Sprague- Dawley rats. Thus, although 5-HT receptors known to mediate vascular relaxation are present in the superior mesenteric artery, they are not functional, and are therefore not likely involved in a 5-HT-induced fall in total peripheral resistance and MAP.

  16. The role of brain 5-hydroxytryptamine in the hyperactivity produced in rats by lithium and monoamine oxidase inhibition

    PubMed Central

    Grahame-Smith, D.G.; Green, A.R.

    1974-01-01

    1 Administration to rats of LiCl (3 mEq/kg) subcutaneously twice daily for 3 days followed by monoamine oxidase inhibition with either tranylcypromine (TCP; 20 mg/kg) or pargyline (75 mg/kg) on the fourth day produces a syndrome of hyperactivity indistinguishable from that produced by monoamine oxidase inhibition and L-tryptophan administration. 2 At least 3 injections of LiCl (3 mEq/kg) are necessary before hyperactivity is seen but one dose of LiCl (10 mEq/kg) 5 h before TCP also caused hyperactivity. The hyperactivity is blocked by prior administration of p-chlorophenylalanine, a tryptophan hydroxylase inhibitor. 3 LiCl pretreatment does not alter the concentration of L-tryptophan in the brain. However after monoamine oxidase inhibition the 5-hydroxytryptamine (5-HT) accumulation was significantly greater in animals given lithium indicating an increase in 5-HT synthesis of 70%. This was confirmed by measuring 5-hydroxyindoleacetic acid accumulation after probenecid (200 mg/kg). 4 The hyperactivity produced by the 5-HT analogue, 5-methoxy N,N-dimethyltryptamine was not potentiaed by lithium pretreatment but one injection of LiCl (3 mEq/kg) which did not alter the rate of 5-HT synthesis, did potentiate the hyperactivity following TCP (20 mg/kg) and L-tryptophan (50 mg/kg). 5 These results suggest that lithium administration may cause an initial alteration of the 5-HT available for release at the nerve ending, which is followed after subsequent treatment by an increase in the rate of 5-HT synthesis. The possible clinical significance of these findings is discussed. PMID:4281339

  17. Prediction of clinical response based on pharmacokinetic/pharmacodynamic models of 5-hydroxytryptamine reuptake inhibitors in mice.

    PubMed

    Kreilgaard, M; Smith, D G; Brennum, L T; Sánchez, C

    2008-09-01

    Bridging the gap between preclinical research and clinical trials is vital for drug development. Predicting clinically relevant steady-state drug concentrations (Css) in serum from preclinical animal models may facilitate this transition. Here we used a pharmacokinetic/pharmacodynamic (PK/PD) modelling approach to evaluate the predictive validity of 5-hydroxytryptamine (5-HT; serotonin) transporter (SERT) occupancy and 5-hydroxytryptophan (5-HTP)-potentiated behavioral syndrome induced by 5-HT reuptake inhibitor (SRI) antidepressants in mice. Serum and whole brain drug concentrations, cortical SERT occupancy and 5-HTP-potentiated behavioral syndrome were measured over 6 h after a single subcutaneous injection of escitalopram, paroxetine or sertraline. [(3)H]2-(2-dimethylaminomethylphenylsulphanyl)-5-methyl-phenylamine ([(3)H]MADAM) was used to assess SERT occupancy. For PK/PD modelling, an effect-compartment model was applied to collapse the hysteresis and predict the steady-state relationship between drug exposure and PD response. The predicted Css for escitalopram, paroxetine and sertraline at 80% SERT occupancy in mice are 18 ng mL(-1), 18 ng mL(-1) and 24 ng mL(-1), respectively, with corresponding responses in the 5-HTP behavioral model being between 20-40% of the maximum. Therapeutically effective SERT occupancy for SRIs in depressed patients is approximately 80%, and the corresponding plasma Css are 6-21 ng mL(-1), 21-95 ng mL(-1) and 20-48 ng mL(-1) for escitalopram, paroxetine and sertraline, respectively. Thus, PK/PD modelling using SERT occupancy and 5-HTP-potentiated behavioral syndrome as response markers in mice may be a useful tool to predict clinically relevant plasma Css values.

  18. Effects of chlorphentermine and phentermine on the pulmonary disposition of 5-hydroxytryptamine in the rat in vivo

    SciTech Connect

    Morita, T.; Mehendale, H.M.

    1983-06-01

    This study was designed to examine whether chlorphentermine (CP) affects pulmonary disposition of 5-hydroxytryptamine (5-HT) in rat in vivo. Further, the effects of CP were compared with those of phentermine (P), the nonchlorinated congener. The right jugular vein and left carotid artery of male Sprague-Dawley rats were cannulated and fresh saline solution containing 150 micrograms indocyanine green and a mixture of labeled and unlabeled 5-HT was injected into the jugular vein, and arterial blood samples were collected for 20 s. In order to compare the effect of CP and P on pulmonary disposition of 5-HT, 2.6 nmol (/sup 14/C)-5-HT was employed for in vivo single-pass experiments. Each animal was used for 2 in vivo single-pass experiments. After the first experiment, which served as a control, animals received an indicated dose of CP or P, to commence the second ''drug-treated'' in vivo experiment. Pulmonary clearance of 5-HT was inhibited by prior administration of CP (1 mg/kg) by 42%, whereas at the highest dose (20 mg/kg) P inhibited 5-HT clearance by only 25%. Pulmonary accumulation of CP was greater than P at higher doses, and the inhibition of 5-HT clearance correlated with the pulmonary accumulation of these drugs. In addition to the in vivo demonstration of the CP inhibition of pulmonary clearance of 5-HT in the rat, these studies also demonstrate a higher affinity of the lung tissue for CP than for P and a greater propensity for the impairment of pulmonary 5-HT clearance.

  19. Changes in 5-hydroxytryptamine and cortisol plasma levels in menopausal women after inhalation of clary sage oil.

    PubMed

    Lee, Kyung-Bok; Cho, Eun; Kang, Young-Sook

    2014-11-01

    The purpose of this study was to examine the antidepressant-like effects of clary sage oil on human beings by comparing the neurotransmitter level change in plasma. The voluntary participants were 22 menopausal women in 50's. Subjects were classified into normal and depression tendency groups using each of Korean version of Beck Depression Inventory-I (KBDI-I), KBDI-II, and Korean version of Self-rating Depression Scale. Then, the changes in neurotransmitter concentrations were compared between two groups. After inhalation of clary sage oil, cortisol levels were significantly decreased while 5-hydroxytryptamine (5-HT) concentration was significantly increased. Thyroid stimulating hormone was also reduced in all groups but not statistically significantly. The different change rate of 5-HT concentration between normal and depression tendency groups was variable according to the depression measurement inventory. When using KBDI-I and KBDI-II, 5-HT increased by 341% and 828% for the normal group and 484% and 257% for the depression tendency group, respectively. The change rate of cortisol was greater in depression tendency groups compared with normal groups, and this difference was statistically significant when using KBDI-II (31% vs. 16% reduction) and Self-rating Depression Scale inventory (36% vs. 8.3% reduction). Among three inventories, only KBDI-II differentiated normal and depression tendency groups with significantly different cortisol level. Finally, clary sage oil has antidepressant-like effect, and KBDI-II inventory may be the most sensitive and valid tool in screening for depression status or severity.

  20. Hypersensitivity of mesenteric veins to 5-hydroxytryptamine- and ketanserin-induced reduction of portal pressure in portal hypertensive rats.

    PubMed Central

    Cummings, S. A.; Groszmann, R. J.; Kaumann, A. J.

    1986-01-01

    Isolated superior mesenteric veins from portal hypertensive rats were 3 to 10 times more sensitive to 5-hydroxytryptamine (5-HT) and 3 times less sensitive to (-)-noradrenaline than veins from sham-operated rats. The sensitivity to vasopressin did not differ in the 2 groups. Ketanserin competitively antagonized the effects of 5-HT in superior mesenteric veins and portal veins with high affinity (KB values 0.1-0.3 nM), as expected for 5-HT2-receptors. The affinity of ketanserin for 5-HT2-receptors was similar in veins from normal, sham-operated or portal-hypertensive rats. Intraportal injections of low doses of 5-HT caused increases in portal pressure which were more pronounced in portal hypertensive rats than in sham-operated rats and were blocked by 0.3 mg kg-1 ketanserin in both groups. Ketanserin 0.3 mg kg-1 did not block the portal pressor response to (-)-noradrenaline in either group of rats. In portal hypertensive rats but not in sham-operated rats, 0.3 mg kg-1 ketanserin caused decreases in portal pressure, portal flow and cardiac output, as estimated by radioactive microspheres. The reduction in portal pressure caused by ketanserin was due mainly to a decrease in portal venous inflow secondary to a decreased cardiac output. The reduction in cardiac output, which was observed only in the portal hypertensive rats but not in sham-operated rats, is consistent with venous dilatation and pooling of blood in the portal venous system. The venous pooling could be secondary to the blockade of 5-HT2-receptors in the portal venous system. It is proposed that ketanserin should be explored for the treatment of patients with portal hypertension. PMID:3801785

  1. Effects of DAU 6215, a novel 5-hydroxytryptamine3 (5-HT3) antagonist on electrophysiological properties of the rat hippocampus.

    PubMed Central

    Passani, M. B.; Pugliese, A. M.; Azzurrini, M.; Corradetti, R.

    1994-01-01

    1. The aim of the present study was to test the effects of DAU 6215 (endo-N-(8-methyl-8-azabicyclo-[3.2.1]-octo-3-yl)-2,3-dihydro-2-ox o-1H- benzimidazole-1-carboxamide carboxamide hydrochloride), a newly synthesized, selective 5-hydroxytryptamine3 (5-HT3) antagonist, on the cell membrane properties and on characterized 5-HT-mediated responses of pyramidal neurones in the hippocampal CA1 region. 2. Administration of DAU 6215, even at concentrations several hundred fold its Ki, did not affect the cell membrane properties of pyramidal neurones, nor modify extracellularly recorded synaptic potentials, evoked by stimulating the Schaffer's collaterals. 3. Micromolar concentrations (15-30 microM) of 5-HT elicited several responses in pyramidal neurones that are mediated by distinct 5-HT receptor subtypes. DAU 6215 did not antagonize the 5-HT1A-induced membrane hyperpolarization and conductance increase, a response that was blocked by the selective 5-HT1A antagonist NAN-190 (1-(2-methoxyphenyl)-4-[4-(2-phtalamido)butyl- piperazine). Similarly, DAU 6215 did not affect the membrane depolarization and decrease in amplitude of the afterhyperpolarization, elicited by the activation of putative 5-HT4 receptors. 4. 5-HT increased the frequency of spontaneous postsynaptic potentials (s.p.s.ps) recorded in pyramidal neurones loaded with chloride. In agreement with previous observations, most of the s.p.s.ps were reversed GABAergic events, produced by the activation of 5-HT3 receptors on interneurones, because they persisted in the presence of the glutamate NMDA and non NMDA antagonists, D-aminophosphonovaleric acid (APV; 50 microM) and 6,7-dinitroquinoxaline-2,3-dione (DNQX; 25 microM), and were elicited by the selective 5-HT3 agonist, 2-methyl-5-HT (2-Me-5-HT, 50 microM).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8075890

  2. Studies of the interaction of 5-hydroxytryptamine and the perivascular innervation of the guinea-pig caecum

    PubMed Central

    Drakontides, Anna B.; Gershon, Michael D.

    1972-01-01

    1. The action and interaction of noradrenaline (NA), 5-hydroxytryptamine (5-HT) and the sympathetic innervation was studied in the isolated taenia of the guinea-pig caecum. 2. Addition of 5-HT led to a contraction of the taenia while addition of NA or perivascular nerve stimulation resulted in relaxation. Responses to 5-HT or perivascular nerve stimulation were abolished by tetrodotoxin. Tetrodotoxin did not affect responses to applied NA. Hexamethonium and hyoscine converted the 5-HT response to a relaxation and augmented the relaxation which followed low frequency perivascular nerve stimulation. Hexamethonium and hyoscine did not affect the dose-response relationship for NA. 3. Fatigue of mechanical responses of the taenia to perivascular nerve stimulation was accelerated when nerves were stimulated in the presence of 5-HT or α-methyl-p-tyrosine (α-MPT). These two agents were additive in this action. 4. Reserpine, 6-hydroxydopamine and α-MPT all reduced the NA content of the taenia. However, only after 6-hydroxydopamine could adrenergic activity be related to NA content. 5. Segments of taenia were incubated with either tritiated NA or 5-HT. An increased rate of release of radioactivity followed perivascular nerve stimulation after incubation with either substance. This release did not occur when tissue was taken from animals given reserpine or 6-hydroxydopamine. 6. It is concluded that 5-HT activates neural elements exclusively while NA has a direct effect on smooth muscle. 5-HT can apparently be taken up by adrenergic axons, and appears to enter the releasable neurotransmitter pool. Since none of the actions characteristic of 5-HT are seen when it is released by adrenergic axons as a false neurotransmitter, the released amine probably fails to reach neuronal receptors for 5-HT. PMID:4342028

  3. Reduced sensitivity to both positive and negative reinforcement in mice over-expressing the 5-hydroxytryptamine transporter.

    PubMed

    Line, Samantha J; Barkus, Chris; Rawlings, Nancy; Jennings, Katie; McHugh, Stephen; Sharp, Trevor; Bannerman, David M

    2014-12-01

    The 5-hydroxytryptamine (5-HT) transporter (5-HTT) is believed to play a key role in both normal and pathological psychological states. Much previous data suggest that the s allele of the polymorphic regulatory region of the 5-HTT gene promoter is associated with reduced 5-HTT expression and vulnerability to psychiatric disorders, including anxiety and depression. In comparison, the l allele, which increases 5-HTT expression, is generally considered protective. However, recent data link this allele to both abnormal 5-HT signalling and psychopathic traits. Here, we studied the processing of aversive and rewarding cues in transgenic mice that over-express the 5-HTT (5-HTTOE mice). Compared with wild-type mice, 5-HTTOE mice froze less in response to both a tone that had previously been paired with footshock, and the conditioning context. In addition, on a decision-making T-maze task, 5-HTTOE mice displayed reduced preference for a larger, delayed reward and increased preference for a smaller, immediate reward, suggesting increased impulsiveness compared with wild-type mice. However, further inspection of the data revealed that 5-HTTOE mice displayed a relative insensitivity to reward magnitude, irrespective of delay. In contrast, 5-HTTOE mice appeared normal on tests of spatial working and reference memory, which required an absolute choice between options associated with either reward or no reward. Overall, the present findings suggest that 5-HTT over-expression results in a reduced sensitivity to both positive and negative reinforcers. Thus, these data show that increased 5-HTT expression has some maladaptive effects, supporting recent suggestions that l allele homozygosity may be a potential risk factor for disabling psychiatric traits.

  4. Treadmill exercise alleviates stress-induced impairment of social interaction through 5-hydroxytryptamine 1A receptor activation in rats.

    PubMed

    Kim, Tae-Woon; Lim, Baek-Vin; Kim, Kijeong; Seo, Jin-Hee; Kim, Chang-Ju

    2015-08-01

    Brain-derived neurotrophic factor (BDNF) and its receptors tyrosine kinase B (trkB), and cyclic adenosine monophosphate response element binding protein (CREB) have been suggested as the neurobiological risk factors causing depressive disorder. Serotonin (5-hydroxytryptamine, 5-HT) plays an important role in the pathogenesis of depression. We in-vestigated the effect of treadmill exercise on social interaction in relation with BDNF and 5-HT expressions following stress in rats. Stress was induced by applying inescapable 0.2 mA electric foot shock to the rats for 7 days. The rats in the exercise groups were forced to run on a motorized treadmill for 30 min once a day for 4 weeks. Social interaction test and western blot for BDNF, TrkB, pCREB, and 5-HT1A in the hippocampus were performed. The results indicate that the spend time with unfamiliar partner was decreased by stress, in contrast, treadmill exercise increased the spending time in the stress-induced rats. Expressions of BDNF, TrkB, and pCREB were decreased by stress, in contrast, treadmill exercise enhanced expressions of BDNF, TrkB, and pCREB in the stress-induced rats. In addition, 5-HT1A receptor expression was de-creased by stress, in contrast, treadmill exercise enhanced 5-HT1A expression in the stress-induced rats. In the present study, treadmill exercise alleviated stress-induced social interaction impairment through enhancing hippocampal plasticity and serotonergic function in the hippocampus. These effects of treadmill exercise are achieved through 5-HT1A receptor activation.

  5. Corticotropin-releasing factor increases GABA synaptic activity and induces inward current in 5-hydroxytryptamine dorsal raphe neurons.

    PubMed

    Kirby, Lynn G; Freeman-Daniels, Emily; Lemos, Julia C; Nunan, John D; Lamy, Christophe; Akanwa, Adaure; Beck, Sheryl G

    2008-11-26

    Stress-related psychiatric disorders such as anxiety and depression involve dysfunction of the serotonin [5-hydroxytryptamine (5-HT)] system. Previous studies have found that the stress neurohormone corticotropin-releasing factor (CRF) inhibits 5-HT neurons in the dorsal raphe nucleus (DRN) in vivo. The goals of the present study were to characterize the CRF receptor subtypes (CRF-R1 and -R2) and cellular mechanisms underlying CRF-5-HT interactions. Visualized whole-cell patch-clamp recording techniques in brain slices were used to measure spontaneous or evoked GABA synaptic activity in DRN neurons of rats and CRF effects on these measures. CRF-R1 and -R2-selective agonists were bath applied alone or in combination with receptor-selective antagonists. CRF increased presynaptic GABA release selectively onto 5-HT neurons, an effect mediated by the CRF-R1 receptor. CRF increased postsynaptic GABA receptor sensitivity selectively in 5-HT neurons, an effect to which both receptor subtypes contributed. CRF also had direct effects on DRN neurons, eliciting an inward current in 5-HT neurons mediated by the CRF-R2 receptor and in non-5-HT neurons mediated by the CRF-R1 receptor. These results indicate that CRF has direct membrane effects on 5-HT DRN neurons as well as indirect effects on GABAergic synaptic transmission that are mediated by distinct receptor subtypes. The inhibition of 5-HT DRN neurons by CRF in vivo may therefore be primarily an indirect effect via stimulation of inhibitory GABA synaptic transmission. These results regarding the cellular mechanisms underlying the complex interaction between CRF, 5-HT, and GABA systems could contribute to the development of novel treatments for stress-related psychiatric disorders.

  6. CORTICOTROPIN-RELEASING FACTOR INCREASES GABA SYNAPTIC ACTIVITY AND INDUCES INWARD CURRENT IN 5-HYDROXYTRYPTAMINE DORSAL RAPHE NEURONS

    PubMed Central

    Kirby, Lynn G.; Freeman-Daniels, Emily; Lemos, Julia C.; Nunan, John D.; Lamy, Christophe; Akanwa, Adaure; Beck, Sheryl G.

    2008-01-01

    Stress-related psychiatric disorders such as anxiety and depression involve dysfunction of the serotonin (5-hydroxytryptamine; 5-HT) system. Previous studies have found that the stress neurohormone corticotropin-releasing factor (CRF) inhibits 5-HT neurons in the dorsal raphe nucleus (DRN) in vivo. The goals of the present study were to characterize the CRF receptor subtypes (CRF-R1 and R2) and cellular mechanisms underlying CRF-5-HT interactions. Visualized whole-cell patch clamp recording techniques in brain slices were used to measure spontaneous or evoked GABA synaptic activity in DRN neurons of rats and CRF effects on these measures. CRF-R1 and -R2-selective agonists were bath applied alone or in combination with receptor-selective antagonists. CRF increased presynaptic GABA release selectively onto 5-HT neurons, an effect mediated by the CRF-R1 receptor. CRF increased postsynaptic GABA receptor sensitivity selectively in 5-HT neurons, an effect to which both receptor subtypes contributed. CRF also had direct effects on DRN neurons, eliciting an inward current in 5-HT neurons mediated by the CRF-R2 receptor and in non 5-HT neurons mediated by the CRF-R1 receptor. These results indicate that CRF has direct membrane effects on 5-HT DRN neurons as well as indirect effects on GABAergic synaptic transmission that are mediated by distinct receptor subtypes. The inhibition of 5-HT DRN neurons by CRF in vivo may therefore be largely an indirect effect via stimulation of inhibitory GABA synaptic transmission. These results regarding the cellular mechanisms underlying the complex interaction between CRF, 5-HT and GABA systems could contribute to the development of novel treatments for stress-related psychiatric disorders. PMID:19036986

  7. The effect of selective 5-hydroxytryptamine uptake inhibitors on 5-methoxy-N,N-dimethyltryptamine-induced ejaculation in the rat.

    PubMed Central

    Rényi, L.

    1986-01-01

    The ejaculatory response and the 5-hydroxytryptamine (5-HT) behavioural syndrome induced by 5-methoxy-N,N-dimethyltryptamine (5-MeODMT) (3 mg kg-1 i.p.) were studied following acute and repeated treatment of rats with the selective uptake inhibitors of 5-HT, fluoxetine, zimeldine, alaproclate, and citalopram. The oral doses used were based on the respective ED50 values for uptake inhibition. Acute doses of fluoxetine and zimeldine significantly reduced the ejaculatory response when given 48 h before 5-MeODMT. This blockade was prevented by treatment of the rats with the postsynaptic 5-HT receptor antagonist methergoline. An acute dose of fluoxetine given 7 and 14 days before 5-MeODMT significantly enhanced the ejaculatory response. On day 24, the response returned to the control level. Repeated treatment every second day (5 times over 9 days and 10 times over 19 days) with fluoxetine caused a longer blockade of the ejaculatory response and the sensitization of the response came later than after an acute dose. Parallel with the ejaculatory response three other components of the 5-HT behavioural syndrome also decreased significantly. Acute doses of alaproclate and citalopram significantly blocked the ejaculatory response at 1 h, but they failed to affect the response at any other time point after either acute or repeated treatment. Neither did these drugs attentuate the 5-HT syndrome. It is concluded that acute and repeated treatment of rats with different selective 5-HT uptake inhibitors does not produce a common alteration in 5-HT2-receptor functions. PMID:2939912

  8. Predictive In Silico Studies of Human 5-hydroxytryptamine Receptor Subtype 2B (5-HT2B) and Valvular Heart Disease

    PubMed Central

    Reid, Terry-Elinor; Kumar, Krishna

    2014-01-01

    Serotonin (5-HT) receptors are neuromodulator neurotransmitter receptors which when activated generate a signal transduction pathway within cells resulting in cell-cell communication. 5-hydroxytryptamine (serotonin) receptor 2B (5-HT2B) is a subtype of the seven members of 5-hydroxytrytamine (5-HT) family of receptors which is the largest member of the super family of 7-transmembrane G-protein coupled receptors (GPCRs). Not only do 5-HT receptors play physiological roles in the cardiovascular system, gastrointestinal and endocrine function and the central nervous, but they also play a role in behavioral functions. In particular 5-HT2B receptor is wide spread with regards to its distribution throughout bodily tissues and is expressed at high levels in the lungs, peripheral tissues, liver, kidney and prostate just to name a few. Hence 5-HT2B participates in multiple biological functions including CNS regulation, regulation of gastrointestinal motality, cardiovascular regulation and 5-HT transport system regulation. While 5-HT2B is a viable drug target and has therapeutic indications for treating obesity, psychotherapy, Parkinson’s disease etc. there is a growing concern regarding adverse drug reactions, specifically valvulopathy associated with 5-HT2B agonists. Due to the sequence homology experienced by 5-HT2 subtypes there is also a concern regarding the off target effects of 5-HT2A and 5-HT2C agonists. The concept of subtype selectivity is of paramount importance and can be tackled with the aid of in silico studies, specifically cheminformatics, to develop models to predict valvulopathy associated toxicity of drug candidates prior to clinical trials. This review has highlighted three in silico approaches thus far that have been successful in either predicting 5-HT2B toxicity of molecules or identifying important interactions between 5-HT2B and drug molecules that bring about valvulopathy related toxicities. PMID:23675941

  9. Treadmill exercise alleviates stress-induced impairment of social interaction through 5-hydroxytryptamine 1A receptor activation in rats

    PubMed Central

    Kim, Tae-Woon; Lim, Baek-Vin; Kim, Kijeong; Seo, Jin-Hee; Kim, Chang-Ju

    2015-01-01

    Brain-derived neurotrophic factor (BDNF) and its receptors tyrosine kinase B (trkB), and cyclic adenosine monophosphate response element binding protein (CREB) have been suggested as the neurobiological risk factors causing depressive disorder. Serotonin (5-hydroxytryptamine, 5-HT) plays an important role in the pathogenesis of depression. We in-vestigated the effect of treadmill exercise on social interaction in relation with BDNF and 5-HT expressions following stress in rats. Stress was induced by applying inescapable 0.2 mA electric foot shock to the rats for 7 days. The rats in the exercise groups were forced to run on a motorized treadmill for 30 min once a day for 4 weeks. Social interaction test and western blot for BDNF, TrkB, pCREB, and 5-HT1A in the hippocampus were performed. The results indicate that the spend time with unfamiliar partner was decreased by stress, in contrast, treadmill exercise increased the spending time in the stress-induced rats. Expressions of BDNF, TrkB, and pCREB were decreased by stress, in contrast, treadmill exercise enhanced expressions of BDNF, TrkB, and pCREB in the stress-induced rats. In addition, 5-HT1A receptor expression was de-creased by stress, in contrast, treadmill exercise enhanced 5-HT1A expression in the stress-induced rats. In the present study, treadmill exercise alleviated stress-induced social interaction impairment through enhancing hippocampal plasticity and serotonergic function in the hippocampus. These effects of treadmill exercise are achieved through 5-HT1A receptor activation. PMID:26331133

  10. Increased extracellular dopamine and 5-hydroxytryptamine levels contribute to enhanced subthalamic nucleus neural activity during exhausting exercise

    PubMed Central

    Hu, Y; Liu, X

    2015-01-01

    The purpose of the study was to explore the mechanism underlying the enhanced subthalamic nucleus (STN) neural activity during exhausting exercise from the perspective of monoamine neurotransmitters and changes of their corresponding receptors. Rats were randomly divided into microdialysis and immunohistochemistry study groups. For microdialysis study, extracellular fluid of the STN was continuously collected with a microdialysis probe before, during and 90 min after one bout of exhausting exercise. Dopamine (DA) and 5-hydroxytryptamine (5-HT) levels were subsequently detected with high-performance liquid chromatography (HPLC). For immunohistochemistry study, the expression of DRD2 and HT2C receptors in the STN, before, immediately after and 90 min after exhaustion was detected through immunohistochemistry technique. Microdialysis study results showed that the extracellular DA and 5-HT neurotransmitters increased significantly throughout the procedure of exhausting exercise and the recovery period (P<0.05 or P<0.01). Immunohistochemistry study results showed that the expression levels of DRD2 and HT2C in the rat STN immediately after exhausting exercise and at the time point of 90 min after exhaustion were both higher than those of the rest condition, but the difference was not significant (P>0.05). Our results suggest that the increased extracellular DA and 5-HT in the STN might be one important factor leading to the enhanced STN neural activity and the development of fatigue during exhausting exercise. This study may essentially offer useful evidence for better understanding of the mechanism of the central type of exercise-induced fatigue. PMID:26424920

  11. The Role of 5-Hydroxytryptamine in the Pathophysiology of Migraine and its Relevance to the Design of Novel Treatments.

    PubMed

    Villalón, Carlos M; VanDenBrink, Antoinette Maassen

    2016-07-28

    Migraine is a highly prevalent neurovascular disorder. Of the many factors that have been implicated over the years, 5-hydroxytryptamine (5-HT; serotonin) has long been involved in the pathophysiology of migraine. Certainly, some lines of evidence suggest: (i) a 5-HT depletion from blood platelets resulting in cranial extracerebral vasodilatation; and (ii) the effectiveness of an intravenous (i.v.) infusion of 5 HT to abort migraine in some patients. More direct evidence comes from some drugs that influence 5-HT release and/or interact (as agonists or antagonists) with 5-HT receptors to treat this disorder. Indeed, the development of sumatriptan and second generation triptans in the 1990's led to discover that these drugs produce selective cranial extracerebral vasoconstriction (via 5 HT1B receptors) and inhibition of the trigeminovascular system responses implicated in migraine (via 5 HT1D/5 HT1F receptors). Although the triptans represent the current mainstay of acute antimigraine treatment, a number of patients do not respond well to the triptans and are contraindicated in patients with cardiovascular pathologies. This mini-review outlines further developments in the design of novel (non-vasoconstrictor) antimigraine treatments acting via 5-HT receptors, including selective agonists at 5 HT1D and 5-HT1F receptors, agonists at 5-HT1B/1D receptors combined with other properties as well as antagonists at 5-HT2B/2C, 5-HT3 and 5 HT7 receptors. It also touches upon the recent development of antagonists and antibodies at calcitonin gene-related peptide (CGRP) and its receptors, which produce a direct blockade of the CGRPergic vasodilator mechanisms involved in migraine. These alternative pharmacological approaches will hopefully lead to less side effects.

  12. Parallel Functional Activity Profiling Reveals Valvulopathogens Are Potent 5-Hydroxytryptamine2B Receptor Agonists: Implications for Drug Safety Assessment

    PubMed Central

    Huang, Xi-Ping; Setola, Vincent; Yadav, Prem N.; Allen, John A.; Rogan, Sarah C.; Hanson, Bonnie J.; Revankar, Chetana; Robers, Matt; Doucette, Chris

    2009-01-01

    Drug-induced valvular heart disease (VHD) is a serious side effect of a few medications, including some that are on the market. Pharmacological studies of VHD-associated medications (e.g., fenfluramine, pergolide, methysergide, and cabergoline) have revealed that they and/or their metabolites are potent 5-hydroxytryptamine2B (5-HT2B) receptor agonists. We have shown that activation of 5-HT2B receptors on human heart valve interstitial cells in vitro induces a proliferative response reminiscent of the fibrosis that typifies VHD. To identify current or future drugs that might induce VHD, we screened approximately 2200 U.S. Food and Drug Administration (FDA)-approved or investigational medications to identify 5-HT2B receptor agonists, using calcium-based high-throughput screening. Of these 2200 compounds, 27 were 5-HT2B receptor agonists (hits); 14 of these had previously been identified as 5-HT2B receptor agonists, including seven bona fide valvulopathogens. Six of the hits (guanfacine, quinidine, xylometazoline, oxymetazoline, fenoldopam, and ropinirole) are approved medications. Twenty-three of the hits were then “functionally profiled” (i.e., assayed in parallel for 5-HT2B receptor agonism using multiple readouts to test for functional selectivity). In these assays, the known valvulopathogens were efficacious at concentrations as low as 30 nM, whereas the other compounds were less so. Hierarchical clustering analysis of the pEC50 data revealed that ropinirole (which is not associated with valvulopathy) was clearly segregated from known valvulopathogens. Taken together, our data demonstrate that patterns of 5-HT2B receptor functional selectivity might be useful for identifying compounds likely to induce valvular heart disease. PMID:19570945

  13. 5-HT1 agonists reduce 5-hydroxytryptamine release in rat hippocampus in vivo as determined by brain microdialysis.

    PubMed Central

    Sharp, T.; Bramwell, S. R.; Grahame-Smith, D. G.

    1989-01-01

    1. An intracerebral perfusion method, brain microdialysis, was used to assess changes of 5-hydroxytryptamine (5-HT) release in the ventral hippocampus of the chloral hydrate-anaesthetized rat in response to systemic administration of a variety of 5-HT1 receptor agonists. 2. A stable output of reliably detectable endogenous 5-HT was measured in dialysates collected from ventral hippocampus with the 5-HT reuptake inhibitor, citalopram, present in the perfusion medium. 3. Under these conditions the putative 5-HT1A agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) caused a dose-dependent (5-250 micrograms kg-1, s.c.) reduction of 5-HT in hippocampal dialysates. 4. Similarly, the putative 5-HT1A agonists gepirone (5 mg kg-1, s.c.), ipsapirone (5 mg kg-1, s.c.) and buspirone (5 mg kg-1, s.c.) markedly reduced levels of 5-HT in hippocampal perfusates whereas their common metabolite 1-(2-pyrimidinyl) piperazine (5 mg kg-1, s.c.), which does not bind to central 5-HT1A recognition sites, had no effect. 5. 5-Methoxy-3-(1,2,3,6-tetrahydro-4-pyridinyl)-1H-indole (RU 24969), a drug with reported high affinity for brain 5-HT1B binding sites, also produced a dose-dependent (0.25-5 mg kg-1, s.c.) decrease of hippocampal 5-HT output. 6. These data are direct biochemical evidence that systemically administered putative 5-HT1A and 5-HT1B agonists markedly inhibit 5-HT release in rat ventral hippocampus in vivo. PMID:2466516

  14. Interaction of tryptamine and ergoline compounds with threonine 196 in the ligand binding site of the 5-hydroxytryptamine6 receptor.

    PubMed

    Boess, F G; Monsma, F J; Meyer, V; Zwingelstein, C; Sleight, A J

    1997-09-01

    We examined the ligand-binding site of the 5-hydroxytryptamine6 (5-HT6) receptor using site-directed mutagenesis. Interactions with residues in two characteristic positions of trans-membrane region V are important for ligand binding in several bioamine receptors. In the 5-HT6 receptor, one of these residues is a threonine (Thr196), whereas in most other mammalian 5-HT receptors, the corresponding residue is alanine. After transient expression in human embryonic kidney 293 cells, we determined the effects of the mutation T196A on [3H]d-lysergic acid diethylamide (LSD) binding and adenylyl cyclase stimulation. This mutation produced a receptor with a 10-fold reduced affinity for [3H]LSD and a 6-fold reduced affinity for 5-HT. The potency of both LSD and 5-HT for stimulation of adenylyl cyclase was also reduced by 18- and 7-fold, respectively. The affinity of other N1-unsubstituted ergolines (e.g., ergotamine, lisuride) was reduced 10-30 fold, whereas the affinity of N1-methylated ergolines (e.g., metergoline, methysergide, mesulergine) and other ligands, such as methiothepine, clozapine, ritanserin, amitriptyline, and mainserin, changed very little or increased. This indicates that in wild-type 5-HT6 receptor, Thr196 interacts with the N1 of N1-unsubstituted ergolines and tryptamines, probably forming a hydrogen bond. Based on molecular modeling, a serine residue in transmembrane region IV of the 5-HT2A receptor has previously been proposed to interact with the N1-position of 5-HT. When the corresponding residue of the 5-HT6 receptor (Ala154) was converted to serine, no change in the affinity of twelve 5-HT6 receptor ligands or in the potency of 5-HT and LSD could be detected, suggesting that this position does not contribute to the ligand binding site of the 5-HT6 receptor.

  15. Characterization of U-92016A as a selective, orally active, high intrinsic activity 5-hydroxytryptamine1A agonist.

    PubMed

    McCall, R B; Romero, A G; Bienkowski, M J; Harris, D W; McGuire, J C; Piercey, M F; Shuck, M E; Smith, M W; Svensson, K A; Schreur, P J

    1994-11-01

    The purpose of the present study was to characterize U-92016A [(+)-R)-2-cyano-N,N-dipropyl-8-amino-6,7,8,9-tetrahydro-3H-benz[e] indole] as a 5-hydroxytryptamine (5-HT)1A receptor agonist and to compare its activity with that of standard 5-HT1A receptor agonists. U-92016A binds with high affinity to human 5-HT1A receptors expressed in Chinese hamster ovary cells (Ki = 0.2 nM). Radioligand binding studies also indicate that U-92016A is selective for the 5-HT1A receptor over other biogenic amine receptors. In Chinese hamster ovary cells expressing the human 5HT1A receptor, U-92016A decreased the forskolin-induced increase in cyclic AMP synthesis and had an intrinsic activity of 0.82 relative to 5-HT. U-92016A potently decreased rectal temperature in mice. The maximum temperature decrease was significantly greater than that observed for 8-hydroxy-di-n-propyl aminotetralin, buspirone, gepirone, ipsapirone or flesinoxan. U-92016A also elicited the 5-HT-mediated syndrome in rats and resulted in a dose-related decrease in 5-hydroxytryptophan accumulation. The compound also decreased arterial blood pressure in spontaneously hypertensive rats and inhibited sympathetic nerve activity in cats. In these assays U-92016A displayed excellent potency and a long duration of action. U-92016A also inhibited the firing of dorsal raphe 5-HT neurons and was active in two social interaction assays. The p.o. bioavailability of U-92016A was calculated to be 45%. Taken together, these data indicate that U-92016A is a metabolically stable, p.o. active 5-HT1A receptor agonist with an exceptionally high degree of intrinsic activity.

  16. False labelling of dopaminergic terminals in the rabbit caudate nucleus: uptake and release of [3H]-5-hydroxytryptamine.

    PubMed Central

    Feuerstein, T. J.; Hertting, G.; Lupp, A.; Neufang, B.

    1986-01-01

    The effect of the catecholamine uptake inhibitor nomifensine and of the 5-hydroxytryptamine (5-HT) uptake blocker 6-nitroquipazine on the accumulation of [3H]-5-HT (0.1 microM, 60 min incubation) and [3H]-dopamine (0.1 microM, 30 min incubation) into slices of hippocampus and caudate nucleus of the rabbit was investigated. In addition, the influence of nomifensine on the electrically evoked [3H]-5-HT release from caudate nucleus slices and of nomifensine and 6-nitroquipazine on [3H]-5-HT released from caudate nucleus slices was analysed. In hippocampal slices, which contain practically no dopaminergic but densely distributed 5-hydroxytryptaminergic and noradrenergic nerve terminals (ratio of dopamine:5-HT:noradrenaline about 1:30:25), nomifensine (1, 10 microM) did not affect the accumulation of [3H]-5-HT; 6-nitroquipazine (1 microM) reduced [3H]-5-HT uptake to about 35% of controls. In the caudate nucleus, however, where dopamine is the predominant monoamine (ratio of dopamine:5-HT:noradrenaline about 400:25:15) nomifensine (1, 10 microM) reduced the tritium accumulation to 65% whereas 6-nitroquipazine (1 microM) was ineffective. The combination of both drugs (1 microM each) led to a further decrease to about 15%. The uptake of [3H]-dopamine into hippocampal slices was blocked by both nomifensine (1 microM) and 6-nitroquipazine (1 microM) whereas in caudate nucleus slices only nomifensine (1, 10 microM) reduced the accumulation of [3H]-dopamine. The combination of both drugs was not more effective than nomifensine alone. The different effects of both uptake inhibitors in the hippocampus and caudate nucleus suggest a neurone specific rather than a substrate specific mode of action.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3742155

  17. Changes in head twitch response induced by a 5-hydroxytryptamine agonist in mice fed a low-protein diet.

    PubMed

    Minakami, K; Shimizu, T; Toriire, Y; Fukuda, T

    1996-01-01

    Long-term intake of a protein diet in infants causes the malnutrition syndrome known as kwashiorkor. Neurological symptoms in kwashiorkor have been reported occasionally. We studied the effects of malnutrition on murine behaviour by feeding growing mice a long-term low-protein diet. Three groups of 3-week-old male ddY mice were fed protein-controlled diets of 8,15 and 25% (control group) of total diet weight for 11 weeks immediately after weaning. The number of head twitches in 2 min were measured 2 min after injection of 10 mg/kg 5 -methoxy- N,N-dimethyltryptamine (5-MeODMT), a 5 -hydroxytryptamine (5 -HT) receptor agonist i.p. Organs were weighed after 10 weeks of feeding. Intracerebral monoamines and their metabolites were assayed using high performance liquid chromatography with electrochemical detection. Bodyweights of mice that were fed the 8% protein diet for 10 weeks were lower than in the other groups. The frequencies of the 5 -MeODMT-induced head twitch in mice that were fed the 8% low-protein diet for 4, 7 and 10 weeks were, respectively, 37.4, 21.4 and 45.2% those of the control group. The frequencies of head twitch also decreased in mice that were fed the 15% low-protein diet for 7 or 10 weeks. The locomotor activity of the mice was unchanged by the amount of protein in the diet. In assays of intracerebral monoamines, 5-HT and 5-HIAA in the whole brain and metabolic turnover of 5-HT increased significantly in mice that were fed the 8% low-protein diet for 11 weeks. Results suggest that head twitches in mice on long-term low-protein diets are suppressed due to the changes in the intracerebral serotonin system.

  18. Contribution of a helix 5 locus to selectivity of hallucinogenic and nonhallucinogenic ligands for the human 5-hydroxytryptamine2A and 5-hydroxytryptamine2C receptors: direct and indirect effects on ligand affinity mediated by the same locus.

    PubMed

    Almaula, N; Ebersole, B J; Ballesteros, J A; Weinstein, H; Sealfon, S C

    1996-07-01

    An important determinant of the neurobehavioral responses induced by a drug is its relative receptor selectivity. The molecular basis of ligand selectivity of hallucinogenic and nonhallucinogenic compounds of varying structural classes for the human 5-hydroxytryptamine (5-HT)2A and 5-HT2C receptors was investigated with the use of reciprocal site-directed mutagenesis. Because these two closely related receptor subtypes differ in the amino acid present at position 5.46 (residues 242 and 222 in the sequences, respectively), the effects of corresponding substitutions in the 5-HT2A[S5.46(242)-->A] and 5-HT2C[A5.46(222)-->S] receptors were studied in tandem. By studying both receptors, the direct and indirect effects of mutations on affinity and selectivity can be distinguished. The ergolines studied, mesulergine (selective for the 5-HT2C receptor) and d-lysergic acid diethylamide (selective for the 5-HT2A receptor), reversed their relative affinity with mutations in each receptor, supporting a direct role of this locus in the selectivity of these ligands. However, interchange mutations in either receptor led to decreased or unchanged affinity for (+/-)-1-)(2,5-dimethoxy-4-iodophenyl)-2-aminopropane and ketanserin, which have higher affinity for the 5-HT2A receptor, consistent with little contribution of this locus to the selectivity of these ligands. The indoleamines studied were affected differently by mutations in each receptor, suggesting that they bind differently to the two receptor subtypes. Mutation of this locus in the 5-HT2A receptor decreased the affinity of all indoleamines, whereas the interchange mutation of the 5-HT2C receptor did not affect indoleamine affinity. These results are consistent with a direct interaction between this side chain and indoleamines for the 5-HT2A receptor but not for the 5-HT2C receptor. Furthermore, this analysis shows that the higher affinity of 5-HT and tryptamine for the 5-HT2C receptor than for the 5-HT2A receptors is not

  19. Histamine and 5-hydroxytryptamine in the intestinal tract of germ-free animals, animals harbouring one microbial species and conventional animals

    PubMed Central

    Beaver, Margaret H.; Wostmann, B. S.

    1962-01-01

    Histamine and 5-hydroxytryptamine were determined in the intestinal tract of germfree and conventional rats and mice. Comparable histamine data were collected in Clostridium perfringens mono-associated rats, while 5-hydroxytryptamine determinations were extended to include the chicken. In rats and mice harbouring an intestinal microflora, bacterial formation of histamine occurs mainly in the caecum. Compared to values found in germ-free animals, histamine levels in the wall of the small intestine of the conventional animal tend to be higher, though in the rat the data are not consistent. Mono-association (harbouring of one microbial species) of germ-free rats with a histamine-producing strain of Clostridium perfringens resulted in high histamine concentrations in the caecal contents, but failed to increase the histamine levels in the wall of the small intestine. 5-Hydroxytryptamine levels in the intestinal wall in the presence of an intestinal flora were generally lower than those in germ-free animals. Modification of the flora by dietary administration of penicillin to mice partly abolished its depressing effect. PMID:13970018

  20. Histamine and 5-hydroxytryptamine in the intestinal tract of germ-free animals, animals harbouring one microbial species and conventional animals.

    PubMed

    BEAVER, M H; WOSTMANN, B S

    1962-12-01

    Histamine and 5-hydroxytryptamine were determined in the intestinal tract of germfree and conventional rats and mice. Comparable histamine data were collected in Clostridium perfringens mono-associated rats, while 5-hydroxytryptamine determinations were extended to include the chicken. In rats and mice harbouring an intestinal microflora, bacterial formation of histamine occurs mainly in the caecum. Compared to values found in germ-free animals, histamine levels in the wall of the small intestine of the conventional animal tend to be higher, though in the rat the data are not consistent. Mono-association (harbouring of one microbial species) of germ-free rats with a histamine-producing strain of Clostridium perfringens resulted in high histamine concentrations in the caecal contents, but failed to increase the histamine levels in the wall of the small intestine. 5-Hydroxytryptamine levels in the intestinal wall in the presence of an intestinal flora were generally lower than those in germ-free animals. Modification of the flora by dietary administration of penicillin to mice partly abolished its depressing effect.

  1. C-reactive protein modulates human lung fibroblast migration.

    PubMed

    Kikuchi, Kazuhiko; Kohyama, Tadashi; Yamauchi, Yasuhiro; Kato, Jun; Takami, Kazutaka; Okazaki, Hitoshi; Desaki, Masashi; Nagase, Takahide; Rennard, Stephen I; Takizawa, Hajime

    2009-02-01

    C-reactive protein (CRP) has been classically used as a marker of inflammation. The aim of this study was to investigate the effect of CRP on migration of human fetal lung fibroblasts (HFL-1) to human plasma fibronectin (HFn). Using the blindwell chamber technique, CRP inhibited HFL-1 migration in a dose-dependent fashion (at 1 microg/mL, inhibition: 32.5% +/- 7.1%; P < .05). Western blot analysis showed that CRP inhibited the p38 mitogen-activated protein kinase (MAPK) activity in the presence of HFn. Moreover, the MAPK inhibitors SB202190 (25 microM) and SB203580 (25 microM) inhibited HFn-induced cell migration, suggesting an important role of p38 MAPK in HFn-induced migration. Taken together, these results suggest that the inhibitory effect of CRP is mediated by blocking MAPK. In summary, this study demonstrates that CRP directly modulates human lung fibroblasts migration. Thus, CRP may contribute to regulation of wound healing and may be endogenous antifibrotic factor acting on lung fibrosis.

  2. The influence of cerebral 5-hydroxytryptamine on catalepsy induced by brain-amine depleting neuroleptics or by cholinomimetics

    PubMed Central

    Fuenmayor, Luis D.; Vogt, Marthe

    1979-01-01

    1 Catalepsy was produced in rats and mice by the subcutaneous injection of either tetrabenazine or the butyrophenone U-32,802A (4′-fluoro-4-{[4-(p-fluorophenyl)-3-cyclohexen-1-yl]amino} butyrophenone hydrochloride). Catalepsy was evaluated by the duration of total immobility on a vertical grid. 2 Pretreatment with p-chlorophenylalanine (PCPA) reduced the intensity of catalepsy by 50% or more, whereas its time course remained the same. 3 5-Hydroxytryptophan (5-HTP), 10 mg/kg, enhanced the catalepsy induced by U-32,802A or tetrabenazine, provided it was administered soon (45 min) after the neuroleptic; injections at 90 min had no effect. Otherwise untreated rats given this dose of 5-HTP behaved normally on the grid. 4 The anticataleptic effect of PCPA was reversed by 5-HTP. 5 Measurable changes in 5-hydroxytryptamine (5-HT) metabolism in the rat forebrain accompanied the modification of catalepsy by 5-HTP and PCPA. 6 Methysergide (5 mg/kg) given 30 min before the neuroleptics to either mice or rats reduced the catalepsy, assessed 2.5 h after the methysergide. It also prevented the increase in neuroleptic-induced catalepsy following 5-HTP, 10 mg/kg. 7 Tryptophan, like 5-HTP, increased the catalepsy seen in mice after U-32,802A and tetrabenazine, and increased the production of 5-hydroxyindol-3-ylacetic acid in the forebrain. 8 In the rat, intracerebroventricular injection of physostigmine produced catalepsy which was not modified by methysergide or PCPA but was abolished by atropine. Similarly, in the mouse, catalepsy induced by the subcutaneous injection of pilocarpine was abolished by atropine but not affected by either methysergide or 5-HTP. 9 Atropine greatly reduced the catalepsy induced by U-32,802A and tetrabenazine but lowered striatal homovanillic acid (HVA) only after U-32,802A. D,L-DOPA, 20 mg/kg, diminished the cataleptogenic effect of both neuroleptics and raised striatal HVA. 10 The results support the view that there is a facilitating or permissive

  3. Lack of 5-hydroxytryptamine1A-mediated inhibition of adenylyl cyclase in dorsal raphe of male and female rats.

    PubMed

    Clarke, W P; Yocca, F D; Maayani, S

    1996-06-01

    In the rat hippocampus, 5-hydroxytryptamine (5-HT)1A receptors couple to two independent effector mechanisms, the inhibition of adenylyl cyclase activity and the opening of a K+ channel. In the dorsal raphe, 5-HT1A receptors also open K+ channels; however, coupling to adenylyl cyclase has not been demonstrated. In this study, the selective 5-HT1A agonists (+/-)- 8-hydroxy-2-(di-n-propylamino)tetralin, (R+)-8-hydroxy-2-(di-n-propylamino)tetralin and dipropyl-5-carboxamidotryptamine, did not inhibit forskolin-stimulated adenylyl cyclase (FSAC) activity in raphe region homogenates, although these drugs were efficacious in hippocampal homogenates. Other 5-HT1A agonists, NAN-190, BMY-7378, buspirone and gepirone, were also ineffective in raphe region homogenates. Estrogen-treatment of ovariectomized female rats, which is known to enhance 5-HT1A-mediated inhibition of FSAC in the hippocampus, did not promote the action of 5-HT1A agonists. Nor did activation of 5-HT1A receptors stimulate basal adenylyl cyclase activity in raphe homogenates as it does in the hippocampus. FSAC activity was inhibited in raphe region homogenates by activation of adenosine A1 or gamma-aminobutyric acidB receptors or by direct activation of the inhibitor G-protein, Gi, with guanyl-5'-6'-imidodiphosphate, indicating that the raphe homogenates have the biochemical machinery for inhibition of FSAC. High affinity binding studies showed that, in raphe homogenates, 5-HT1A receptors were expressed at a density comparable to that of adenosine A1 receptors and that they were coupled to G-proteins. It should be noted that our failure to observe 5-HT1A-mediated inhibition of adenylyl cyclase in the raphe does not prove that such coupling does not exist. However, a lack of 5-HT1A receptor coupling to adenylyl cyclase in the raphe would support contentions that coupling of the 5-HT1A receptor to adenylyl cyclase may be independent of its coupling to the K+ channel and that there may be distinct differences

  4. Antagonism of fenfluramine-induced hyperthermia in rats by some, but not all, selective inhibitors of 5-hydroxytryptamine uptake.

    PubMed Central

    Sugrue, M. F.

    1984-01-01

    The injection of fenfluramine (7.5 mg kg-1,i.p.) to rats housed at 27-28 degrees C was associated with an elevation of core body temperature which peaked at approximately 1 h post-injection. One h pretreatment with citalopram (20 mg kg-1, i.p.), chlorimipramine (10 mg kg-1, i.p.), femoxetine (10 mg kg-1, i.p.) and fluoxetine (20 mg kg-1, i.p.) resulted in an attenuated response to fenfluramine. In contrast, Org 6582 (20 mg kg-1) and zimelidine (20 mg kg-1) were devoid of an effect on fenfluramine-induced hyperthermia. The response to fenfluramine was was also blocked by i.p. injections of metergoline (0.2 mg kg-1), methysergide (5 mg kg-1) and mianserin (0.5 mg kg-1). Rectal temperature was unaltered by both the 5-hydroxytryptamine (5-HT) uptake inhibitors and the 5-HT receptor antagonists. The IC50 values (nM) for in vitro inhibition of [3H]-5-HT uptake into rat hypothalamic synaptosomes were for citalopram 2.4, chlorimipramine 8.8, femoxetine 14, fluoxetine 16, Org 6582 75 and zimelidine 250. The injection of all six compounds (20 mg kg-1, i.p.) 1 h before death was associated with an inhibition of [3H]-5-HT uptake into rat hypothalamic synaptosomes which ranged from 47.2% for chlorimipramine to 83.3% for citalopram. Rat hypothalamic 5-HT levels were decreased by approximately 50% 3 h after the injection of fenfluramine (15 mg kg-1, i.p.). This effect was blocked by a 1 h pretreatment with fluoxetine, Org 6582 and zimelidine (all 20 mg kg-1, i.p.). Ki values for displacement of specifically bound [3H]-5-HT (1 nM) to rat hypothalamic membranes were for metergoline 26 nM, methysergide 1.1 microM, mianserin 3.6 microM, chlorimipramine 9.2 microM and fluoxetine 32.7 microM. Values for citalopram, femoxetine, Org 6582 and zimelidine were in excess of 65.4 microM.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6722394

  5. Adrenoceptor- and cholinoceptor-mediated mechanisms in the regulation of 5-hydroxytryptamine release from isolated tracheae of newborn rabbits.

    PubMed Central

    Freitag, A.; Wessler, I.; Racké, K.

    1996-01-01

    1. Isolated tracheae of newborn rabbits were incubated in vitro and the outflow of 5-hydroxytryptamine (5-HT) was determined by h.p.l.c. with electrochemical detection. Evidence has previously been provided that this 5-HT outflow derives from neuroendocrine epithelial (NEE) cells of the airway mucosa. 2. Phenylephrine (1, 10 and 30 microM) enhanced the outflow of 5-HT by 80, 290 and 205%, respectively. 5-HT outflow evoked by 10 microM phenylephrine was not affected by the presence of the neurotoxin tetrodotoxin (1 microM). 3. Rauwolscine, ARC 239 (an alpha(2B)-adrenoceptor preferring antagonist), yohimbine and prazosin antagonized the effect of 10 microM phenylephrine in a concentration-dependent manner with IC50 values of 150, 295, 300 and 1,700 nM, respectively. Comparison of the ratios (between all antagonists) of the present IC50 values with the corresponding ratios of Ki values obtained in binding studies for the alpha(2A)-, alpha(2B)-, alpha(2C)- and alpha(2D)-adrenoceptor subtypes strongly suggests the involvement of an alpha(2B)-receptor. 4. 5-HT outflow evoked by 10 microM phenylephrine was inhibited by 65% in the presence of 1 microM forskolin and abolished in the presence of 10 microM forskolin. 5. 5-HT outflow evoked by 10 microM phenylephrine was inhibited by about 45 and 70% in the presence of 0.1 and 1 microM isoprenaline, respectively. The inhibitory effect of 1 microM isoprenaline was only marginally antagonized by 1 microM, but blocked by 10 microM propranolol. 6. 5-HT outflow was not affected by the muscarine receptor agonist oxotremorine (10 microM), but was enhanced by 175% by 100 microM nicotine. The effect of nicotine was blocked by 100 microM hexamethonium and prevented by 1 microM tetrodotoxin or 1 microM yohimbine. 7. In conclusion, 5-HT release from NEE cells of the rabbit trachea is stimulated via alpha-adrenoceptors most likely of the alpha(2B)-subtype localized directly at the NEE cells. Activation of beta-adrenoceptors as well as

  6. Microtopography and flow modulate the direction of endothelial cell migration.

    PubMed

    Uttayarat, P; Chen, M; Li, M; Allen, F D; Composto, R J; Lelkes, P I

    2008-02-01

    The migration of vascular endothelial cells under flow can be modulated by the addition of chemical or mechanical stimuli. The aim of this study was to investigate how topographic cues derived from a substrate containing three-dimensional microtopography interact with fluid shear stress in directing endothelial cell migration. Subconfluent bovine aortic endothelial cells were seeded on fibronectin-coated poly(dimethylsiloxane) substrates patterned with a combinatorial array of parallel and orthogonal microgrooves ranging from 2 to 5 microm in width at a constant depth of 1 microm. During a 4-h time-lapse observation in the absence of flow, the majority of the prealigned cells migrated parallel to the grooves with the distribution of their focal adhesions (FAs) depending on the groove width. No change in this migratory pattern was observed after the cells were exposed to moderate shear stress (13.5 dyn/cm(2)), irrespective of groove direction with respect to flow. After 4-h exposure to high shear stress (58 dyn/cm(2)) parallel to the grooves, the cells continued to migrate in the direction of both grooves and flow. By contrast, when microgrooves were oriented perpendicular to flow, most cells migrated orthogonal to the grooves and downstream with flow. Despite the change in the migration direction of the cells under high shear stress, most FAs and actin microfilaments maintained their original alignment parallel to the grooves, suggesting that topographic cues were more effective than those derived from shear stress in guiding the orientation of cytoskeletal and adhesion proteins during the initial exposure to flow.

  7. Involvement of 5-hydroxytryptamine 5-HT₃ serotonergic receptors in the acquisition and reinstatement of the conditioned place preference induced by MDMA.

    PubMed

    Roger-Sánchez, Concepción; Rodríguez-Arias, Marta; Miñarro, Jose; Aguilar, Maria A

    2013-08-15

    Some MDMA (3,4-methylenedioxymethamphetamine) users develop dependence as a result of chronic consumption. The present study evaluated the role of 5-hydroxytryptamine 5-HT₃ receptors in the acquisition, expression and reinstatement of the conditioned place preference (CPP) induced by MDMA. Adolescent male mice were conditioned with 10 mg/kg of MDMA and then treated with 1 or 3mg/kg of the 5-hydroxytryptamine 5-HT₃ antagonist MDL72222 during acquisition of conditioning (experiment 1), before expression of CPP in a post-conditioning test (experiment 2) or before a reinstatement test (experiment 3). MDL72222 was devoid of motivational effects but blocked acquisition of the MDMA-induced CPP. Moreover, following extinction, the low dose of MDL72222 blocked reinstatement of the CPP induced by priming with MDMA. Acute MDMA reduced levels of dihydroxypheylacetic acid (DOPAC) in the striatum and levels of acid 5-hydroxyindoleacetic (5-HIAA) in the cortex. Acute MDMA+MDL72222 also reduced striatal DOPAC. The repeated co-administration of MDMA plus MDL72222 (on PND 32-34-36-38) increased dopamine and decreased DOPAC in the striatum, and increased cortical serotonin and enhanced transporters of dopamine and serotonin. The acute administration (on PND ±55) of MDMA or MDL72222 increased levels of dopamine and reduced those of DOPAC in the striatum and co-administration of MDMA plus MDL72222 increased striatal serotonin. Our results confirm that 5-hydroxytryptamine 5-HT₃ receptors are involved in the acquisition of conditioned rewarding effects of MDMA and demonstrate that these receptors are also involved in reinstatement after extinction.

  8. Blockade of 5-hydroxytryptamine3 receptors prevents cisplatin-induced but not motion- or xylazine-induced emesis in the cat

    NASA Technical Reports Server (NTRS)

    Lucot, J. B.

    1989-01-01

    5-Hydroxytryptamine3 antagonists have been reported to prevent emesis elicited by cisplatin and radiation. This study investigated the possibility that drugs with this mechanism of action may be useful in preventing emesis elicited by other stimuli. The drugs ICS 205-930 (0.1 and 1.0 mg/kg) and MDL 72222 (0.1 and 1.0 mg/kg) were administered SC to cats before challenging them with either provocative motion or an emetic dose of xylazine. In no instance was a significant reduction in emesis evident. Zacopride was also administered before motion testing (0.01 to 10.0 mg/kg) and found to not have efficacy. To test the possibility that species or route of administration were factors in the negative results, 1.0 mg/kg of ICS 205-930 was administered SC before IV infusion of 7.5 mg/kg of cisplatin. There was a total suppression of emesis for the duration of the six-hour observation periods. This result verifies other work which found 5-hydroxytryptamine3 antagonists to be effective in preventing emesis elicited by cancer chemotherapeutic treatments. However, there is no evidence that they are effective in other syndromes, such as motion sickness and xylazine-induced emesis.

  9. Does pharmacogenomics account for variability in control of acute chemotherapy-induced nausea and vomiting with 5-hydroxytryptamine type 3 receptor antagonists?

    PubMed

    Trammel, Morgan; Roederer, Mary; Patel, Jai; McLeod, Howard

    2013-06-01

    Chemotherapy-induced nausea and vomiting is one of the most concerning adverse drug effects from cytotoxic chemotherapy. Despite appropriate use of antiemetic guidelines, 20-30 % of patients experience breakthrough nausea and vomiting secondary to chemotherapy. To assess the variability of 5-hydroxytryptamine type 3 receptor antagonist efficacy caused by genetic variation, a review of the available literature was conducted. From the literature, three sources of pharmacogenomic variability were identified: polymorphisms associated with 5-hydroxytryptamine type 3 receptor subunits, drug metabolism via cytochromes P450, and drug transport in the body. Testing for receptor subunit polymorphisms is not applicable to a clinical setting at this time; however, cytochrome P450 2D6 testing is FDA-approved and widely accessible. Cytochrome P450 2D6 ultrarapid metabolizers and poor metabolizers displayed altered antiemetic efficacy when compared with intermediate metabolizers and extensive metabolizers. We postulate that testing for cytochrome P450 2D6 phenotypes may be the most accessible way to provide individualized antiemetic therapy in the future.

  10. Blockade of 5-hydroxytryptamine3 receptors prevents cisplatin-induced but not motion- or xylazine-induced emesis in the cat

    NASA Technical Reports Server (NTRS)

    Lucot, J. B.

    1989-01-01

    5-Hydroxytryptamine3 antagonists have been reported to prevent emesis elicited by cisplatin and radiation. This study investigated the possibility that drugs with this mechanism of action may be useful in preventing emesis elicited by other stimuli. The drugs ICS 205-930 (0.1 and 1.0 mg/kg) and MDL 72222 (0.1 and 1.0 mg/kg) were administered SC to cats before challenging them with either provocative motion or an emetic dose of xylazine. In no instance was a significant reduction in emesis evident. Zacopride was also administered before motion testing (0.01 to 10.0 mg/kg) and found to not have efficacy. To test the possibility that species or route of administration were factors in the negative results, 1.0 mg/kg of ICS 205-930 was administered SC before IV infusion of 7.5 mg/kg of cisplatin. There was a total suppression of emesis for the duration of the six-hour observation periods. This result verifies other work which found 5-hydroxytryptamine3 antagonists to be effective in preventing emesis elicited by cancer chemotherapeutic treatments. However, there is no evidence that they are effective in other syndromes, such as motion sickness and xylazine-induced emesis.

  11. Prophylaxis of Radiation-Induced Nausea and Vomiting Using 5-Hydroxytryptamine-3 Serotonin Receptor Antagonists: A Systematic Review of Randomized Trials

    SciTech Connect

    Salvo, Nadia; Doble, Brett; Khan, Luluel; Amirthevasar, Gayathri; Dennis, Kristopher; Pasetka, Mark; DeAngelis, Carlo; Tsao, May; Chow, Edward

    2012-01-01

    Purpose: To systematically review the effectiveness and safety of 5-hydroxytryptamine-3 receptor antagonists (5-HT3 RAs) compared with other antiemetic medication or placebo for prophylaxis of radiation-induced nausea and vomiting. Methods and Materials: We searched the following electronic databases: MEDLINE, Embase, the Cochrane Central Register of Controlled Clinical Trials, and Web of Science. We also hand-searched reference lists of included studies. Randomized, controlled trials that compared a 5-HT3 RA with another antiemetic medication or placebo for preventing radiation-induced nausea and vomiting were included. We excluded studies recruiting patients receiving concomitant chemotherapy. When appropriate, meta-analysis was conducted using Review Manager (v5) software. Relative risks were calculated using inverse variance as the statistical method under a random-effects model. We assessed the quality of evidence by outcome using the Grading of Recommendations Assessment, Development, and Evaluation approach. Results: Eligibility screening of 47 articles resulted in 9 included in the review. The overall methodologic quality was moderate. Meta-analysis of 5-HT3 RAs vs. placebo showed significant benefit for 5-HT3 RAs (relative risk [RR] 0.70; 95% confidence interval [CI] 0.57-0.86 for emesis; RR 0.84, 95% CI 0.73-0.96 for nausea). Meta-analysis comparing 5-HT3 RAs vs. metoclopramide showed a significant benefit of the 5-HT3 RAs for emetic control (RR 0.27, 95% CI 0.15-0.47). Conclusion: 5-Hydroxytryptamine-3 RAs are superior to placebo and other antiemetics for prevention of emesis, but little benefit was identified for nausea prevention. 5-Hydroxytryptamine-3 RAs are suggested for prevention of emesis. Limited evidence was found regarding delayed emesis, adverse events, quality of life, or need for rescue medication. Future randomized, controlled trials should evaluate different 5-HT3 antiemetics and new agents with novel mechanisms of action such at the NK

  12. Methylene blue modulates transendothelial migration of peripheral blood cells.

    PubMed

    Werner, Isabella; Guo, Fengwei; Bogert, Nicolai V; Stock, Ulrich A; Meybohm, Patrick; Moritz, Anton; Beiras-Fernandez, Andres

    2013-01-01

    Vasoplegia is a severe complication after cardiac surgery. Within the last years the administration of nitric oxide synthase inhibitor methylene blue (MB) became a new therapeutic strategy. Our aim was to investigate the role of MB on transendothelial migration of circulating blood cells, the potential role of cyclic cGMP, eNOS and iNOS in this process, and the influence of MB on endothelial cell apoptosis. Human vascular endothelial cells (HuMEC-1) were treated for 30 minutes or 2 hours with different concentrations of MB. Inflammation was mimicked by LPS stimulation prior and after MB. Transmigration of PBMCs and T-Lymphocytes through the treated endothelial cells was investigated. The influence of MB upon the different subsets of PBMCs (Granulocytes, T- and B-Lymphocytes, and Monocytes) was assessed after transmigration by means of flow-cytometry. The effect of MB on cell apoptosis was evaluated using Annexin-V and Propidium Iodide stainings. Analyses of the expression of cyclic cGMP, eNOS and iNOS were performed by means of RT-PCR and Western Blot. Results were analyzed using unpaired Students T-test. Analysis of endothelial cell apoptosis by MB indicated a dose-dependent increase of apoptotic cells. We observed time- and dose-dependent effects of MB on transendothelial migration of PBMCs. The prophylactic administration of MB led to an increase of transendothelial migration of PBMCs but not Jurkat cells. Furthermore, HuMEC-1 secretion of cGMP correlated with iNOS expression after MB administration but not with eNOS expression. Expression of these molecules was reduced after MB administration at protein level. This study clearly reveals that endothelial response to MB is dose- and especially time-dependent. MB shows different effects on circulating blood cell-subtypes, and modifies the release patterns of eNOS, iNOS, and cGMP. The transendothelial migration is modulated after treatment with MB. Furthermore, MB provokes apoptosis of endothelial cells in a dose

  13. Methylene Blue Modulates Transendothelial Migration of Peripheral Blood Cells

    PubMed Central

    Werner, Isabella; Guo, Fengwei; Bogert, Nicolai V.; Stock, Ulrich A.; Meybohm, Patrick; Moritz, Anton; Beiras-Fernandez, Andres

    2013-01-01

    Vasoplegia is a severe complication after cardiac surgery. Within the last years the administration of nitric oxide synthase inhibitor methylene blue (MB) became a new therapeutic strategy. Our aim was to investigate the role of MB on transendothelial migration of circulating blood cells, the potential role of cyclic cGMP, eNOS and iNOS in this process, and the influence of MB on endothelial cell apoptosis. Human vascular endothelial cells (HuMEC-1) were treated for 30 minutes or 2 hours with different concentrations of MB. Inflammation was mimicked by LPS stimulation prior and after MB. Transmigration of PBMCs and T-Lymphocytes through the treated endothelial cells was investigated. The influence of MB upon the different subsets of PBMCs (Granulocytes, T- and B-Lymphocytes, and Monocytes) was assessed after transmigration by means of flow-cytometry. The effect of MB on cell apoptosis was evaluated using Annexin-V and Propidium Iodide stainings. Analyses of the expression of cyclic cGMP, eNOS and iNOS were performed by means of RT-PCR and Western Blot. Results were analyzed using unpaired Students T-test. Analysis of endothelial cell apoptosis by MB indicated a dose-dependent increase of apoptotic cells. We observed time- and dose-dependent effects of MB on transendothelial migration of PBMCs. The prophylactic administration of MB led to an increase of transendothelial migration of PBMCs but not Jurkat cells. Furthermore, HuMEC-1 secretion of cGMP correlated with iNOS expression after MB administration but not with eNOS expression. Expression of these molecules was reduced after MB administration at protein level. This study clearly reveals that endothelial response to MB is dose- and especially time-dependent. MB shows different effects on circulating blood cell-subtypes, and modifies the release patterns of eNOS, iNOS, and cGMP. The transendothelial migration is modulated after treatment with MB. Furthermore, MB provokes apoptosis of endothelial cells in a dose

  14. Blockade of 5-hydroxytryptamine(3) receptors prevents cisplatin-induced but not motion- or xylazine-induced emesis in the cat

    NASA Technical Reports Server (NTRS)

    Lucot, James B.

    1989-01-01

    The effects of the 5-hydroxytryptamine(3) (5-HT-3) antagonists ICS 205-930 and MDL 72222 on the emesis induced by motion or by emetic doses of xylazine (0.66 mg/kg administered SC) or cisplatin (7.5 mg/kg infused over a period of 4-5 min) were investigated in cats. It was found that neither the low (0.1 mg/kg) or the high (1.0 mg.kg) doses of ICS 205-930 or MDL 72222 prevented emesis elicited by screening motion challenges or xylazine. On the other hand, treatment cats by 1.0 mg/kg of ICS 205-930 was effective against cisplatin-induced motion sickness, in agreement with earlier results obtained on other mammals.

  15. 5-hydroxytryptamine receptor (5-HT1DR) promotes colorectal cancer metastasis by regulating Axin1/β-catenin/MMP-7 signaling pathway

    PubMed Central

    Ji, Qing; Liu, Xuan; Zhou, Lihong; Song, Haiyan; Zhou, Xiqiu; Xu, Yangxian; Chen, Zhesheng; Cai, Jianfeng; Ji, Guang; Li, Qi

    2015-01-01

    Overexpression of 5-hydroxytryptamine (5-HT) in human cancer contributes to tumor metastasis, but the role of 5-HT receptor family in cancer has not been thoroughly explored. Here, we report overexpression of 5-HT1D receptor (5-HT1DR) was associated with Wnt signaling pathway and advanced tumor stage. The underlying mechanism of 5-HT1DR-promoted tumor invasion was through its activation on the Axin1/β-catenin/MMP-7 pathway. In an orthotopic colorectal cancer mouse model, we demonstrated that a 5-HT1DR antagonist (GR127935) effectively inhibited tumor metastasis through targeting Axin1. Furthermore, in intestinal epithelium cells, we observed that 5-HT1DR played an important role in cell invasion via Axin1/β-catenin/MMP-7 pathway. Together, our findings reveal an essential role of the physiologic level of 5-HT1DR in pulmonary metastasis of colorectal cancer. PMID:26214021

  16. Effects of p-chlorophenylalanine on the sensitivity of rat intestine to agonists and on intestinal 5-hydroxytryptamine levels during Nippostrongylus brasiliensis infection.

    PubMed Central

    Farmer, S. G.; Laniyonu, A. A.

    1984-01-01

    Infection of rats with the nematode N. brasiliensis caused non-specific increases in maximum response of isolated intestine to acetylcholine and 5-hydroxytryptamine (5-HT), and a specific subsensitivity to 5-HT. Intestinal levels of 5-HT, measured fluorimetrically, increased approximately 2 fold during infection. Treatment of infected rats with parachlorophenylalanine (PCPA) depleted the gut of 5-HT, and prevented the specific subsensitivity to the amine but not the increases in maximum response. Depletion of intestinal 5-HT did not prevent the immune expulsion of the parasites. It is concluded that the specific subsensitivity of the gut is due to the elevated levels of 5-HT during infection, but that the increased maximum responses are due to some other factor. Further, the lack of effect of PCPA on parasite rejection casts doubt on the proposed role of 5-HT in this process. PMID:6236863

  17. Comparison of the performance of different DFT methods in the calculations of the molecular structure and vibration spectra of serotonin (5-hydroxytryptamine, 5-HT)

    NASA Astrophysics Data System (ADS)

    Yang, Yue; Gao, Hongwei

    2012-04-01

    Serotonin (5-hydroxytryptamine, 5-HT) is a monoamine neurotransmitter which plays an important role in treating acute or clinical stress. The comparative performance of different density functional theory (DFT) methods at various basis sets in predicting the molecular structure and vibration spectra of serotonin was reported. The calculation results of different methods including mPW1PW91, HCTH, SVWN, PBEPBE, B3PW91 and B3LYP with various basis sets including LANL2DZ, SDD, LANL2MB, 6-31G, 6-311++G and 6-311+G* were compared with the experimental data. It is remarkable that the SVWN/6-311++G and SVWN/6-311+G* levels afford the best quality to predict the structure of serotonin. The results also indicate that PBEPBE/LANL2DZ level show better performance in the vibration spectra prediction of serotonin than other DFT methods.

  18. Blockade of 5-hydroxytryptamine(3) receptors prevents cisplatin-induced but not motion- or xylazine-induced emesis in the cat

    NASA Technical Reports Server (NTRS)

    Lucot, James B.

    1989-01-01

    The effects of the 5-hydroxytryptamine(3) (5-HT-3) antagonists ICS 205-930 and MDL 72222 on the emesis induced by motion or by emetic doses of xylazine (0.66 mg/kg administered SC) or cisplatin (7.5 mg/kg infused over a period of 4-5 min) were investigated in cats. It was found that neither the low (0.1 mg/kg) or the high (1.0 mg.kg) doses of ICS 205-930 or MDL 72222 prevented emesis elicited by screening motion challenges or xylazine. On the other hand, treatment cats by 1.0 mg/kg of ICS 205-930 was effective against cisplatin-induced motion sickness, in agreement with earlier results obtained on other mammals.

  19. 5-Hydroxytryptamine1A receptor-activation hyperpolarizes pyramidal cells and suppresses hippocampal gamma oscillations via Kir3 channel activation.

    PubMed

    Johnston, April; McBain, Chris J; Fisahn, André

    2014-10-01

    Rhythmic cortical neuronal oscillations in the gamma frequency band (30-80 Hz, gamma oscillations) have been associated with cognitive processes such as sensory perception and integration, attention, learning, and memory. Gamma oscillations are disrupted in disorders for which cognitive deficits are hallmark symptoms such as schizophrenia and Alzheimer's disease.In vitro, various neurotransmitters have been found to modulate gamma oscillations. Serotonin(5-HT) has long been known to be important for both behavioural and cognitive functions such as learning and memory. Multiple 5-HT receptor subtypes are expressed in the CA3 region of the hippocampus and high doses of 5-HT reduce the power of induced gamma oscillations.Hypothesizing that 5-HT may have cell- and receptor subtype-specific modulatory effects, we investigated the receptor subtypes, cell types and cellular mechanisms engaged by 5-HT in the modulation of gamma oscillations in mice and rats. We found that 5-HT decreases the power of kainate-induced hippocampal gamma oscillations in both species via the 5-HT1A receptor subtype. Whole-cell patch clamp recordings demonstrated that this decrease was caused by a hyperpolarization of CA3 pyramidal cells and a reduction of their firing frequency, but not by alteration of inhibitory neurotransmission. Finally, our results show that the effect on pyramidal cells is mediated via the G protein-coupled receptor inwardly rectifying potassium channel Kir3.Our findings suggest this novel cellular mechanism as a potential target for therapies that are aimed at alleviating cognitive decline by helping the brain to maintain or re-establish normal gamma oscillation levels in neuropsychiatric and neurodegenerative disorders.

  20. Effects of the benzodiazepine receptor agonist midazolam and antagonist flumazenil on 5-hydroxytryptamine release from guinea-pig intestine in vitro. Indirect support for a "natural" benzodiazepine-like substance in the intestine.

    PubMed

    Racké, K; Schwörer, H; Kilbinger, H

    1990-01-01

    Isolated segments of the guinea-pig small intestine and the guinea-pig stomach were vascularly perfused and the release of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid into the portal venous effluent determined by high pressure liquid chromatography with electrochemical detection. Test substances were applied intraarterially. The benzodiazepine receptor agonist, midazolam, concentration-dependently increased (by 58%, at 1 nmol/l) and decreased (by 32%, at 100 nmol/l) the release of 5-HT from small intestine preparations. Both effects were blocked by the benzodiazepine receptor antagonist flumazenil (10 nmol/l) The stimulatory effect of midazolam was also abolished in the presence of tetrodotoxin (1 mumol/l) or scopolamine (100 nmol/l). In the absence of tetrodotoxin, flumazenil (10 nmol/l) alone decreased the release of 5-HT from the small intestine by 41%, but it increased the release of 5-HT by 50% in the presence of tetrodotoxin. Both effects of flumazenil were abolished in the presence of bicuculline (50 mumol/l). In the absence of tetrodotoxin, flumazenil (10 nmol/l) decreased also the release of 5-HT and its metabolite from the perfused stomach by about 40%, whereas midazolam (1 nmol/l) caused an increase by about 60%. In conclusion, benzodiazepine receptors modulate the previously described intrinsic GABAergic regulation of 5-HT release from enterochromaffin cells in the guinea-pig intestine. It is suggested that an endogenous benzodiazepine-like substance of non-neuronal origin is present in the small intestine and stomach of the guinea-pig.

  1. The effect of three products of cigarette smoke (cyanide, thiocyanate and nicotine) on the concentration-response curves of 5-hydroxytryptamine, norepinephrine and epinephrine in the isolated human umbilical veins and arteries.

    PubMed

    Tunçel, N; Aydin, Y; Tikiz, H

    1994-02-01

    The effect of cyanide (10(-7) M), thiocyanate (10(-4) M) and nicotine (10(-7) M) on the concentration-response curves of 5-hydroxytryptamine, norepinephrine and epinephrine were investigated in human isolated umbilical arteries and veins. Cyanide significantly affected the responses of arterial strips to 5-hydroxytryptamine, norepinephrine and epinephrine: It caused significant leftward shifts of the 5-hydroxytryptamine concentration-response curves and significantly potentiated the contractile effects of norepinephrine and epinephrine in the case of norepinephrine, and epinephrine concentration reached 10(-6) and 10(-7) M respectively in the bath medium. Cyanide did not show any significant effect on the concentration-response curves of 5-hydroxytryptamine, norepinephrine and epinephrine in veins. Nicotine interacted with the response of adrenergic agonists both in arteries and veins; in arteries it potentiates the contractile response of epinephrine; in veins, it inhibited the dilatory responses of norepinephrine and potentiated the contractile effect of high concentration of epinephrine (10(-6) M). Thiocyanate did not cause any difference on any cumulative concentration-response curves either on the vessels. However, none of these individual effects of cyanide and nicotine were observed when the cyanide, thiocyanate and nicotine were added in combination in the isolated organ bath medium.

  2. Effect of Panax ginseng and diazepam on brain 5-hydroxytryptamine and its modification by diclofenac in rat.

    PubMed

    Bhattcharyya, D; Sur, T K

    1999-10-01

    Wistar male rats pretreated with anti-stress agents like, Panax ginseng (Pg) and diazepam (Diaz) were stressed by restraining for 1 h and 5-HT content of brain and hypothalamus as well as plasma corticosterone were measured spectrophotoflurometrically. Diclofenac (DICLO), a prostaglandin (PG) synthesis inhibitor was used to confirm the role of prostaglandin in restraint stress-induced elevation of central 5-HT correspondingly confirmed by elevation of plasma corticosterone and modification of the above anti-stress agents. Pg, Diaz and DICLO per se did not modify brain and hypothalamic 5-HT in control rats. But they attenuated stress-induced elevation of brain and hypothalamic 5-HT. Anti-stress action of both Pg and Diaz reflected by inhibition of stress-induced elevation of brain and hypothalamic content of 5-HT as also stress-induced concurrent elevation of plasma corticosterone were further diminished by DICLO. The mediatory action of 5-HT in anti-stress effects of Pg and Diaz may be modulated through prostaglandins.

  3. A phase 1 randomized study evaluating the effect of omeprazole on the pharmacokinetics of a novel 5-hydroxytryptamine receptor 4 agonist, revexepride (SSP-002358), in healthy adults

    PubMed Central

    Pierce, David; Corcoran, Mary; Velinova, Maria; Hossack, Stuart; Hoppenbrouwers, Mieke; Martin, Patrick

    2015-01-01

    Background About 30% of patients with gastroesophageal reflux disease continue to experience symptoms despite treatment with proton pump inhibitors. The 5-hydroxytryptamine 4 receptor agonist revexepride (SSP-002358) is a novel prokinetic that stimulates gastrointestinal motility, which has been suggested as a continued cause of symptoms in these patients. The aim of this study was to assess whether revexepride pharmacokinetics were affected by co-administration of omeprazole, in preparation for a proof-of-concept evaluation of revexepride added to proton pump inhibitor treatment. Methods In this phase 1, open-label, randomized, two-period crossover study, healthy adults aged 18–55 years were given a single dose of revexepride 1 mg or revexepride 1 mg + omeprazole 40 mg. Pharmacokinetic parameters were assessed for up to 48 hours after administration of the investigational product. Adverse events, clinical chemistry and hematology parameters, electrocardiograms, and vital signs were monitored. Results In total, 42 participants were enrolled and 40 completed the study. The median age was 24 years (18–54 years), 55% were women and 93% were white. The pharmacokinetic parameters of revexepride were similar without or with omeprazole co-administration. The mean area under the plasma concentration–time curve from time 0 to infinity (AUC0–∞) was 23.3 ng · h/mL (standard deviation [SD]: 6.33 ng · h/mL) versus 24.6 ng · h/mL (SD: 6.31 ng · h/mL), and maximum plasma concentrations (Cmax) were 3.89 ng/mL (SD: 1.30 ng/mL) and 4.12 ng/mL (SD: 1.29 ng/mL) in participants without and with omeprazole, respectively. For AUC0–∞ and Cmax, the 90% confidence intervals for the ratios of geometric least-squares means (with:without omeprazole) were fully contained within the pre-defined equivalence limits of 0.80–1.25. Mean apparent terminal phase half-life was 9.95 hours (SD: 2.06 hours) without omeprazole, and 11.0 hours (SD: 3.25 hours) with omeprazole. Conclusion

  4. Simultaneous determination of 5-hydroxyindoleacetic acid and 5-hydroxytryptamine in urine samples from patients with acute appendicitis by liquid chromatography using poly(bromophenol blue) film modified electrode.

    PubMed

    Xu, Haihong; Zhang, Wen; Wang, Dan; Zhu, Wei; Jin, Litong

    2007-02-01

    The fabrication and application of a novel electrochemical detection (ED) system with a poly(bromophenol blue) (PBPB) film chemically modified electrode (CME) for high performance liquid chromatography (HPLC) were described. The electrochemical behaviors of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) at this CME were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). It was found that the PBPB CME efficiently exhibited electrocatalytic effect on the current responses of 5-HT and 5-HIAA with relatively high sensitivity, stability and long life of activity. In HPLC-ED, the two analytes had good and stable current responses at the CME and their linear ranges were over four orders of magnitude (R> or =0.9992) with the detection limits being 0.25 nmol L(-1) for 5-HT and 0.50 nmol L(-1) for 5-HIAA. The application of this method for the determination of 5-HT and 5-HIAA in urine samples from patients with acute appendicitis (AA) was satisfactory.

  5. gamma-Aminobutyric acid-A receptor-mediated suppression of 5-hydroxytryptamine-induced guinea-pig basilar artery smooth muscle contractility.

    PubMed

    Shirakawa, J; Hosoda, K; Taniyama, K; Matsumoto, S; Tanaka, C

    1989-01-01

    The mechanism of gamma-aminobutyric acid (GABA)-induced suppression of 5-hydroxytryptamine (5HT)-induced contractility of cerebral blood vessels was studied in single smooth muscle cells isolated from the guinea-pig basilar artery. GABA reduced 5HT-induced contraction of single smooth muscle cells, and the effect of GABA was mimicked by muscimol, but not baclofen. The response of muscimol was antagonized by bicuculline, thereby indicating that GABAA receptors exist on the smooth muscle of the basilar artery. Since GABA did not change the contraction induced by the addition of Ca2+ to the Ca2+-free medium in the presence of high K+, it is unlikely that GABA inhibits the influx of extracellular Ca2+. The caffeine-induced contraction in the Ca2+-free medium was reduced by GABA, and the effect of GABA was not obtained by treatment with furosemide and in the Cl- -free medium. These results indicate that GABA acts on the GABAA receptor located on smooth muscle cells and reduces the contractility of the basilar artery by suppression of the mobilization of intracellular Ca2+.

  6. Detection of 5-hydroxytryptamine (5-HT) in vitro using a hippocampal neuronal network-based biosensor with extracellular potential analysis of neurons.

    PubMed

    Hu, Liang; Wang, Qin; Qin, Zhen; Su, Kaiqi; Huang, Liquan; Hu, Ning; Wang, Ping

    2015-04-15

    5-hydroxytryptamine (5-HT) is an important neurotransmitter in regulating emotions and related behaviors in mammals. To detect and monitor the 5-HT, effective and convenient methods are demanded in investigation of neuronal network. In this study, hippocampal neuronal networks (HNNs) endogenously expressing 5-HT receptors were employed as sensing elements to build an in vitro neuronal network-based biosensor. The electrophysiological characteristics were analyzed in both neuron and network levels. The firing rates and amplitudes were derived from signal to determine the biosensor response characteristics. The experimental results demonstrate a dose-dependent inhibitory effect of 5-HT on hippocampal neuron activities, indicating the effectiveness of this hybrid biosensor in detecting 5-HT with a response range from 0.01μmol/L to 10μmol/L. In addition, the cross-correlation analysis of HNNs activities suggests 5-HT could weaken HNN connectivity reversibly, providing more specificity of this biosensor in detecting 5-HT. Moreover, 5-HT induced spatiotemporal firing pattern alterations could be monitored in neuron and network levels simultaneously by this hybrid biosensor in a convenient and direct way. With those merits, this neuronal network-based biosensor will be promising to be a valuable and utility platform for the study of neurotransmitter in vitro.

  7. The effects of single and repeated electroconvulsive shock administration on the release of 5-hydroxytryptamine and noradrenaline from cortical slices of rat brain.

    PubMed Central

    Green, A. R.; Heal, D. J.; Vincent, N. D.

    1987-01-01

    1 A method is described of measuring the K+-evoked release of endogenous 5-hydroxytryptamine (5-HT) and noradrenaline (NA) from slices prepared from rat cortex. 2 There was no difference in either the spontaneous (basal) or K+-evoked release of 5-HT or NA from cortical slices prepared from handled animals and those given a single electroconvulsive shock (ECS) either 30 min or 24 h earlier. 3 In chronic studies, rats were either handled or given an ECS 5 times over 10 days and cortical slices prepared. There was no difference in 5-HT or NA release between the groups 30 min after the last treatment other than a modest attentuation of spontaneous NA release following ECS treatment. However 24 h after the last treatment K+-evoked release (above basal release) of 5-HT and NA was inhibited by 84% and 48%, respectively. 4 These data demonstrate that following a single ECS, normal 5-HT and NA release is seen at a time when GABA release is markedly inhibited. After repeated ECS the release of both monoamines was markedly inhibited. These 5-HT changes may be involved in the enhanced 5-HT-receptor function seen after repeated ECS. PMID:3664089

  8. The mechanism of body temperature changes induced by intraventricular injections of adrenaline, noradrenaline and 5-hydroxytryptamine in the ox (bos taurus)

    PubMed Central

    Findlay, J. D.; Robertshaw, D.

    1967-01-01

    1. Adrenaline, noradrenaline and 5-hydroxytryptamine (5-HT) were injected into the lateral ventricle of the ox. The effect of these drugs was measured on the respiratory rate, tidal volume, heat production, skin temperature of the ear, evaporative loss from the skin and the rectal temperature at 20 and 10° C ambient temperature. 2. Neither adrenaline (3 mg) nor noradrenaline (3 mg) had any effect on the temperature regulating mechanisms of the ox, except to produce vasoconstriction if vasodilatation was already present due to high ambient temperature or previous injection of 5-HT. 3. Injection of 5-HT (5 mg) caused a rise in respiratory rate, a fall in tidal volume and heat production, elevation of ear skin temperature and skin evaporative loss and a decrease in rectal temperature. Sedation of the animals occurred. 4. In its reaction to these monoamines the ox is similar to the goat, sheep and rabbit, but is unlike the cat and dog. 5. It was concluded that neither adrenaline nor noradrenaline has a role in the central control of temperature regulation in the ox, but that 5-HT may be involved in the control of heat dissipation mechanisms. PMID:6034117

  9. Effects of 5,7-dihydroxytryptamine on an identified 5-hydroxytryptamine-containing neurone in the central nervous sytem of the snail Helix pomatia.

    PubMed

    Osborne, N N; Pentreath, V W

    1976-01-01

    1. The effect of 5,7-dihydroxytryptamine (5,7-DHT) on an identified 5-hydroxytryptamine (5-HT)-containing neurone in the CNS of the snail was studied by histochemical, biochemical and electrophysiological methods. 2. Low concentrations of 5,7-DHT decreased the endogenous 5-HT content of the neurone without affecting the amino acids, while relatively large amounts of the drug proportionately lowered 5-HT and in addition slightly decreased the tryptophan and methionine content of the cell. 3. 5,7-DHT blocked the uptake of [3H]-5-HT into the neurone; the close analogue 5,6-DHT was more potent. 4. As well as slightly influencing the accumulation of [3H]-tryptophan by the neurone 5,7-DHT inhibited the metabolism of this amino acid to form 5-HT, probably by affecting the enzyme tryptophan-hydroxylase. 5. 5,7-DHT produced a postsynaptic blockade of transmission from the neurone by blocking the 5-HT receptors of the follower neurones. This effect appeared to be specific for 5-HT receptors. 6. The data support the idea that 5,7-DHT is neurotoxic for indoleamine-containing neurones.

  10. Postnatal Treadmill Exercise Alleviates Prenatal Stress-Induced Anxiety in Offspring Rats by Enhancing Cell Proliferation Through 5-Hydroxytryptamine 1A Receptor Activation

    PubMed Central

    2016-01-01

    Purpose: Stress during pregnancy is a risk factor for the development of anxiety-related disorders in offspring later in life. The effects of treadmill exercise on anxiety-like behaviors and hippocampal cell proliferation were investigated using rats exposed to prenatal stress. Methods: Exposure of pregnant rats to a hunting dog in an enclosed room was used to induce stress. Anxiety-like behaviors of offspring were evaluated using the elevated plus maze test. Immunohistochemistry for the detection of 5-bromo-2ʹ- deoxyuridine and doublecortin (DCX) in the hippocampal dentate gyrus and 5-hydroxytryptamine 1A receptors (5-HT1A) in the dorsal raphe was conducted. Brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) levels in the hippocampus were evaluated by western blot analysis. Results: Offspring of maternal rats exposed to stress during pregnancy showed anxiety-like behaviors. Offspring also showed reduced expression of BDNF, TrkB, and DCX in the dentate gyrus, decreased cell proliferation in the hippocampus, and reduced 5-HT1A expression in the dorsal raphe. Postnatal treadmill exercise by offspring, but not maternal exercise during pregnancy, enhanced cell proliferation and expression of these proteins. Conclusions: Postnatal treadmill exercise ameliorated anxiety-like behaviors in offspring of stressed pregnant rats, and the alleviating effect of exercise on these behaviors is hypothesized to result from enhancement of cell proliferation through 5-HT1A activation in offspring rats. PMID:27230461

  11. Interaction between the effects of 5-hydroxytryptamine and adrenaline on the growth of platelet thrombi in the coronary artery of the anaesthetized dog.

    PubMed Central

    McAuliffe, S. J.; Snow, H. M.; Cox, B.; Smith, C. C.; Noble, M. I.

    1993-01-01

    1. The interaction between adrenaline and 5-hydroxytryptamine (5-HT) has been quantitated on the rate of thrombus formation, in the stenosed coronary artery with damaged endothelium of the anaesthetized dog. 2. Changes in the plasma concentration of adrenaline were produced by varying the rate of an intravenous infusion of adrenaline and in the effects of 5-HT, by intravenous injections of the selective 5-HT2 receptor antagonist, ICI 170809. 3. Increases in the plasma concentration of adrenaline, which did not cause significant changes in blood pressure and heart rate, increased the rate of thrombus formation. 4. Antagonism of the 5-HT2 receptor by ICI 170809, in the absence of an infusion of adrenaline, abolished thrombus formation (mean ED50 0.41 microgram kg-1, i.v.). 5. The effects of adrenaline were non-competitively antagonized by ICI 170809; maximum effects were obtained in the dose-range 50-200 micrograms kg-1, i.v., when the mean dose-ratio increase in adrenaline required to restore equivalent rates of thrombus formation was 39 fold. 6. These results are consistent with a synergism between adrenaline and 5-HT and emphasize the importance of both on thrombus formation. PMID:8358542

  12. Sensitive determination of norepinephrine, epinephrine, dopamine and 5-hydroxytryptamine by coupling HPLC with [Ag(HIO6 )2 ](5-) -luminol chemiluminescence detection.

    PubMed

    Wu, Dong; Xie, He; Lu, Haifeng; Li, Wei; Zhang, Qunlin

    2016-09-01

    Based on the enhancing effects of norepinephrine (NE), epinephrine (EP), dopamine (DA) and 5-hydroxytryptamine (5-HT) on the chemiluminescence (CL) reaction between [Ag(HIO6 )2 ](5-) and luminol in alkaline solution, a high-performance liquid chromatography (HPLC) method with CL detection was explored for the sensitive determination of monoamine neurotransmitters for the first time. The UV-visible absorption spectra were recorded to study the enhancement mechanism of monoamine neurotransmitters on the CL of [Ag(HIO6 )2 ](5-) and luminol reaction. The HPLC separation of NE, EP, DA and 5-HT was achieved with isocratic elution using a mixture of aqueous 0.2% phosphoric acid and methanol (5:95, v/v) within 11.0 min. Under the optimized conditions, the detection limits of NE, EP, DA, and 5-HT were 4.8, 0.9, 1.9 and 2.3 ng/mL, respectively, corresponding to 17.6-96.0 pg for 20 μL sample injection. The recoveries of monoamine neurotransmitters in rat brain were >95.6% with the precisions expressed by RSD <5.0%. The validated HPLC-CL method was successfully applied for the quantification of NE, EP, DA and 5-HT in rat brain. This method has promising potential for some biological and clinical investigations focusing on the levels of monoamine neurotransmitters. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Simultaneous quantification of 5-hydroxyindoleacetic acid and 5-hydroxytryptamine by capillary electrophoresis with quantum dot and horseradish peroxidase enhanced chemiluminescence detection.

    PubMed

    Zhang, Liangliang; Zhao, Yunsha; Huang, Junming; Zhao, Shulin

    2014-09-15

    A capillary electrophoresis (CE) with chemiluminescence (CL) detection method was developed for the simultaneous quantification of 5-hydroxyindoleacetic acid (5-HIAA) and 5-hydroxytryptamine (5-HT). In this method, CdTe quantum dot (QD) and horseradish peroxidase (HRP) were used as enhancing reagents to co-catalyze the post-column CL reaction between luminol and hydrogen peroxide, achieving highly efficient CL emission. 5-HIAA and 5-HT inhibit the CL emission resulting to the formation of negative peaks in electropherogram. The degree of CL suppression is proportional to the concentration of 5-HT and 5-HIAA. The linear ranges for the determination of 5-HIAA and 5-HT were 2.5×10(-8)-2.5×10(-6) M and 2.5×10(-8)-5.0×10(-6) M with detection limits (signal/noise=3) of 7.0×10(-9) M and 6.0×10(-9) M, respectively. Intraday precision do not exceed 5.0%. The accuracy was confirmed by the recoveries ranged from 98% to 104%. The present method was successfully applied for the quantification of 5-HIAA and 5-HT in human urine. The concentrations of 5-HT and 5-HIAA in human urine were found to be in the range of 0.78-1.2 μM and 3.2-5.1 μM, respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Changes in the regulation of 5-hydroxytryptamine release by alpha2-adrenoceptors in the rat hippocampus after long-term desipramine treatment.

    PubMed

    Yoshioka, M; Matsumoto, M; Numazawa, R; Togashi, H; Smith, C B; Saito, H

    1995-12-29

    In vivo microdialysis was used to measure the effects of long-term treatment of rats with desipramine upon the regulation by alpha2-adrenoceptors of serotonin (5-hydroxytryptamine, 5-HT) release from the serotonergic neurons in the hippocampus. Rats were injected with saline or desipramine, 10 mg/kg, i.p., every 12 h for 14 days. When added to the perfusion solution, brimonidine, an alpha2-adrenoceptor agonist, significantly inhibited the K+-evoked release of 5-HT in the hippocampi of saline-treated, control rats. This action of brimonidine was prevented by pretreating the rats with idazoxan, an alpha2-adrenoceptor antagonist. Long-term desipramine treatment significantly reduced the inhibitory effect of brimonidine upon the K+-evoked 5-HT release. With long-term administration of desipramine, noradrenaline content in the hippocampi was significantly decreased as compared with that of the control rats, whereas the basal noradrenaline concentration in the dialysate was significantly increased. On the other hand, both the 5-HT content of the hippocampus and the basal 5-HT concentration in the dialysate were significantly increased. The present study suggests that long-term administration of desipramine causes a functional subsensitivity of the presynaptic alpha2-adrenoceptors that regulate serotonergic neuronal function in the rat hippocampus. It also supports the concept that changes in the sensitivity of alpha2-adrenoceptors that regulate neurotransmitter release play an important role in the mechanism of antidepressant drug action.

  15. Separate 5-hydroxytryptamine receptors on the salivary gland of the blowfly are linked to the generation of either cyclic adenosine 3',5'-monophosphate or calcium signals.

    PubMed Central

    Berridge, M. J.; Heslop, J. P.

    1981-01-01

    1 5'-Hydroxytryptamine (5-HT) stimulates the formation of two separate second messengers in the salivary gland of the blowfly. Activation of adenylate cyclase raises adenosine 3',5'-monophosphate (cyclic AMP) whereas the hydrolysis of phosphatidylinositol (PI) is associated with an increase in calcium permeability. The possibility that these two signal pathways might be controlled by separate 5-HT receptors was studied by testing the specificity of 5-HT analogues and antagonists. 2 The parent compound 5-HT was found to stimulate both cyclic AMP formation and the related parameters of PI hydrolysis and calcium transport with similar dose-response relationships. 3 Certain analogues such as 4- and 5-fluoro-alpha-methyltryptamine were capable of raising cyclic AMP levels and stimulating fluid secretion but did not stimulate the hydrolysis of PI or the entry of calcium. 4 Other analogues, which had chloro or methyl substituents at the 5-position, were found to stimulate the hydrolysis of PI and the transport of calcium at much lower doses than those required to stimulate the formation of cyclic AMP. 5 Antagonists were also found to exert selective effects. Methysergide was a potent inhibitor of PI hydrolysis whereas cinanserin was far more selective in blocking the stimulatory effect of 5-HT on cyclic AMP formation. 6 It is concluded that 5-HT acts on two separate receptors, a 5-HT1 receptor acting through calcium and a 5-HT2 receptor which mediates its effects through cyclic AMP. PMID:6265018

  16. Effects of methysergide and 5-hydroxytryptamine on carotid blood flow distribution in pigs: further evidence for the presence of atypical 5-HT receptors.

    PubMed Central

    Saxena, P. R.; Verdouw, P. D.

    1984-01-01

    The effects of acute (50-350 micrograms kg-1, i.v.) and subacute (350 micrograms kg-1 orally per day for six days) administration of methysergide, and of intra-arterial infusions of 0.5 and 2.0 micrograms kg-1 min-1 5-hydroxytryptamine (5-HT) on the distribution of carotid blood flow into the capillary (nutrient) and arterio-venous anastomotic (AVA) fractions were studied in anaesthetized pigs. The acute, but not the subacute, administration of methysergide caused a moderate reduction of carotid blood flow. This reduction, noticed only in the AVA fraction, was due to a constriction of the arterio-venous anastomoses (AVAs). Both doses of 5-HT reduced total carotid blood flow but its nutrient fraction--particularly that distributed to the skin and ears--increased substantially. The AVA fraction was greatly diminished. After treatment with methysergide, 5-HT no longer reduced the total carotid blood flow, but increased it. Despite this reversal the constriction of AVAs by the amine was only slightly diminished. On the other hand, the vasodilatation of the nutrient channels was enhanced. The results of the interaction between methysergide and 5-HT provide further evidence for the presence of 'atypical' 5-HT receptors (probably corresponding to 5-HT1 binding sites) mediating AVA contraction and nutrient vasodilatation. The 5-HT2 receptors mediate vasoconstriction and are located in the large conducting arteries and possibly, in smaller numbers, in the AVAs and arterioles. PMID:6478112

  17. The effect of noradrenaline and 5-hydroxytryptamine injected into a lateral cerebral ventricle, on thermoregulation in the new-born lamb.

    PubMed Central

    Cooper, K E; Pittman, Q J; Veale, W L

    1976-01-01

    1. Respiratory frequency, shivering, ear skin temperatures and rectal temperatures were observed following intraventricular injections of noradrenaline (NA), 5-hydroxytryptamine (5-HT) and saline (NaCl) into new-born lambs exposed to ambient temperatures of 4, 21, or 30 degrees C. 2. Intraventricular NA caused respiratory rate to decrease and body temperature to increase in the 30 degrees C environment. At 21 degrees C, it increased ear skin temperature but did not significantly affect rectal temperature. At 4 degrees C, NA decreased shivering and rectal temperature fell. 3. 5-HT elevated respiratory rate in the 30 degrees C environment and increased ear skin temperature in the 21 and 4 degrees C environments. In the 4 degrees C environment rectal temperature decreased. 4. In general, the change in rectal temperature was related to the dosage of drug administered. Control injections of NaCl had no significant effect on any of the variables measured. 5. The monoaminergic pathways involved in thermoregulation in the new-born lamb appear to be organized in a manner similar to that of the adult sheep and are functional at birth. PMID:994031

  18. Interaction between the effects of spinal heating and cooling and of injections into a lateral cerebral ventricle of noradrenaline, 5-hydroxytryptamine and carbachol on thermoregulation in sheep.

    PubMed Central

    Bacon, M; Bligh, J

    1976-01-01

    1. A study has been made of the interactions of the thermoregulatory effects of spinal cord heating and cooling and of the injections into the cerebral ventricle of noradrenaline, 5-hydroxytryptamine (5-HT) and carbamylcholine in sheep. 2. The interactions of spinal cord heating and the injections into the cerebral ventricle of noradrenaline, 5-HT and carbamylcholine were very similar to those of hypothalamic heating or of high ambient temperature and the injections into the cerebral ventricle of these substances. These results are interpreted as evidence of the synaptic convergence of the pathways from peripheral, spinal cord and hypothalamic warm-sensors at or before the points of action of these synaptically active substances. 3. The only definite thermoregulatory effect of spinal cooling was the onset of shivering which could be due to a purely spinal effect of cold. No substantial evidence was obtained of an interaction between spinal cooling and an injection of noradrenaline, 5-HT or carbamylcholine into the cerebral ventricle. Thus there was no clear indication of centripetal pathways from spinal cold sensors converging with those from the skin and the hypothalamus for which evidence of convergence was obtained in an earlier study. 4. The results of this study are expressed in terms of the neuronal model of Bligh, Cottle & Maskrey (1971) and Maskrey & Bligh (1971), appropriately modified. PMID:1249731

  19. Effects of 5,7-dihydroxytryptamine on an identified 5-hydroxytryptamine-containing neurone in the central nervous sytem of the snail Helix pomatia.

    PubMed Central

    Osborne, N N; Pentreath, V W

    1976-01-01

    1. The effect of 5,7-dihydroxytryptamine (5,7-DHT) on an identified 5-hydroxytryptamine (5-HT)-containing neurone in the CNS of the snail was studied by histochemical, biochemical and electrophysiological methods. 2. Low concentrations of 5,7-DHT decreased the endogenous 5-HT content of the neurone without affecting the amino acids, while relatively large amounts of the drug proportionately lowered 5-HT and in addition slightly decreased the tryptophan and methionine content of the cell. 3. 5,7-DHT blocked the uptake of [3H]-5-HT into the neurone; the close analogue 5,6-DHT was more potent. 4. As well as slightly influencing the accumulation of [3H]-tryptophan by the neurone 5,7-DHT inhibited the metabolism of this amino acid to form 5-HT, probably by affecting the enzyme tryptophan-hydroxylase. 5. 5,7-DHT produced a postsynaptic blockade of transmission from the neurone by blocking the 5-HT receptors of the follower neurones. This effect appeared to be specific for 5-HT receptors. 6. The data support the idea that 5,7-DHT is neurotoxic for indoleamine-containing neurones. Images Figure 1 Figure 3 PMID:1252663

  20. Alterations of central serotonin and dopamine turnover in rats treated with ipsapirone and other 5-hydroxytryptamine1A agonists with potential anxiolytic properties.

    PubMed

    Hamon, M; Fattaccini, C M; Adrien, J; Gallissot, M C; Martin, P; Gozlan, H

    1988-08-01

    Measurements of tissue levels of monoamines and their metabolites, and of the rates of 5-hydroxytryptophan and dihydroxy-phenylalanine accumulation after blockade of aromatic amino acid decarboxylase by benserazid indicated that ipsapirone (1-10 mg/kg i.p.) decreased 5-hydroxytryptamine (5-HT) turnover and accelerated dopamine (DA) turnover in various brain regions. The reduced 5-HT turnover probably resulted from the stimulation of 5-HT1A autoreceptors within the anterior raphe nuclei as in vitro tests [( 3H]-8-hydroxy-2-[di-n-propylamino]tetralin binding and adenylate cyclase assays) demonstrated that ipsapirone was a 5-HT1A agonist almost as potent as 8-OH-DPAT, and the same decrease in 5-hydroxytryptophan accumulation could be induced by the i.p. (5 mg/kg) or intraraphe (1 microgram) injection of ipsapirone. Ipsapirone-induced acceleration of DA turnover persisted after the selective degeneration of serotoninergic neurons by intraraphe 5,7-dihydroxytryptamine infusion, and could be reproduced by i.p. administration of other 5-HT1A agonists like buspirone and gepirone, but not 8-OH-DPAT. These results demonstrate that ipsapirone-induced acceleration of DA turnover did not result from the stimulation of 5-HT1A (auto)receptors, but involved additional target(s) of the drug. The possible participation of dopaminergic systems in the "anxiolytic" properties of ipsapirone should deserve further investigations.

  1. A slow voltage-dependent Na(+)-current induced by 5-hydroxytryptamine and the G-protein-coupled activation mechanism in the ganglion cells of Aplysia.

    PubMed

    Kudo, A; Sasaki, K; Tamazawa, Y; Matsumoto, M

    1991-01-01

    Application of 5-hydroxytryptamine (5HT) induces a slowly depolarizing response in the neurons of Aplysia abdominal ganglion. In voltage-clamped cells, 5HT induced a slow inward current that increased steeply with membrane depolarization from -85 mV showing a negative slope conductance, but never reversed into outward when hyperpolarized beyond the equilibrium potential for K+. The 5HT-induced response was markedly augmented in Ca(2+)-free media, but depressed in Na(+)-free media, and unaffected by a change in external potassium. Intracellular injection of guanosine 5'-O-(2-thiodiphosphate) (GDP beta S) significantly depressed the 5HT response in a dose-dependent way. Injection of cholera toxin (CTX) selectively blocked the 5HT-induced response, the effect being irreversible. Neither 3'-deoxyadenosine, an inhibitor of adenylate cyclase, nor H-8, an inhibitor of protein kinase A, depressed the 5HT response. 3-Isobutyl-1-methylxanthine (IBMX) did not augment the 5HT response appreciably. The 5HT responses were not depressed at all during a saturated response to Br-cyclic AMP injected intracellularly. It was concluded that the 5HT response is produced by opening of the voltage-dependent Na(+)-channels with activation of CTX-sensitive G-protein but not necessarily with an increase in intracellular cyclic AMP.

  2. Modulation of human eosinophil polymorphonuclear leukocyte migration and function.

    PubMed Central

    Goetzl, E. J.

    1976-01-01

    Eosinophil migration toward a concentration gradient of a chemotactic factor is regulated at four levels. Diverse immunologic pathways generate stimuli with eosinophil chemotactic activity, including the complement products C5a and a fragment of C3a and the peptide products of mast cells and basophils activated by IgE-mediated reactions, such as eosinophil chemotactic factor of anaphylaxis (ECF-A) and other oligopeptides. The intrinsic preferential leukocyte activity of the chemotactic stimuli represents the second level of modulation, with ECF-A and other mast cell-derived peptides exhibiting the most selective action on eosinophils. The third level of control of eosinophil chemotaxis is composed of inactivators and inhibitors of chemotactic stimuli and is exemplified by degradation of C5a by anaphylatoxin inactivator or chemotactic factor inactivator and of ECF-A by carboxypeptidase-A or aminopeptidases. The activity of ECF-A is uniquely suppressed by equimolar quantities of its NH2- terminal tripeptide substituent, presumably by eosinophil membrane receptor competition. Factors comprising the fourth level of regulation, which alter eosinophil responsiveness to chemotactic stimuli, include the chemotactic factors themselves, through deactivation; nonchemotactic inhibitors such as the COOH-terminal tripeptide substituent of ECF-A, the neutrophil-immobilizing factor (NIF), the phagocytosis-enhancing factor Thr-Lys-Pro-Arg, and histamine at concentrations greater than 400 ng/ml; and nonchemotactic enhancing principles represented by ascorbate and by histamine at concentrations of 30 ng/ml or less. Local concentrations of eosinophils called to and immobilized at the site of a hypersenitivity reaction may express their regulatory functions by degrading the chemical mediators elaborated including histamine, slow-reacting substance of anaphylaxis (SRS-A), and platelet-activating factor (PAF) by way of their content of histaminase, arylsulfatase B, and phospholipase D

  3. Pharmacological profile of lurasidone, a novel antipsychotic agent with potent 5-hydroxytryptamine 7 (5-HT7) and 5-HT1A receptor activity.

    PubMed

    Ishibashi, Tadashi; Horisawa, Tomoko; Tokuda, Kumiko; Ishiyama, Takeo; Ogasa, Masaaki; Tagashira, Rie; Matsumoto, Kenji; Nishikawa, Hiroyuki; Ueda, Yoko; Toma, Satoko; Oki, Hitomi; Tanno, Norihiko; Saji, Ikutaro; Ito, Akira; Ohno, Yukihiro; Nakamura, Mitsutaka

    2010-07-01

    Lurasidone [(3aR,4S,7R,7aS)-2-[(1R,2R)-2-[4-(1,2-benzisothiazol-3-yl)piperazin-1-ylmethyl]cyclohexylmethyl]hexahydro-4,7-methano-2H-isoindole-1,3-dione hydrochloride; SM-13496] is an azapirone derivative and a novel antipsychotic candidate. The objective of the current studies was to investigate the in vitro and in vivo pharmacological properties of lurasidone. Receptor binding affinities of lurasidone and several antipsychotic drugs were tested under comparable assay conditions using cloned human receptors or membrane fractions prepared from animal tissue. Lurasidone was found to have potent binding affinity for dopamine D(2), 5-hydroxytryptamine 2A (5-HT(2A)), 5-HT(7), 5-HT(1A), and noradrenaline alpha(2C) receptors. Affinity for noradrenaline alpha(1), alpha(2A), and 5-HT(2C) receptors was weak, whereas affinity for histamine H(1) and muscarinic acetylcholine receptors was negligible. In vitro functional assays demonstrated that lurasidone acts as an antagonist at D(2) and 5-HT(7) receptors and as a partial agonist at the 5-HT(1A) receptor subtype. Lurasidone showed potent effects predictive of antipsychotic activity, such as inhibition of methamphetamine-induced hyperactivity and apomorphine-induced stereotyped behavior in rats, similar to other antipsychotics. Furthermore, lurasidone had only weak extrapyramidal effects in rodent models. In animal models of anxiety disorders and depression, treatment with lurasidone was associated with significant improvement. Lurasidone showed a preferential effect on the frontal cortex (versus striatum) in increasing dopamine turnover. Anti-alpha(1)-noradrenergic, anticholinergic, and central nervous system (CNS) depressant actions of lurasidone were also very weak. These results demonstrate that lurasidone possesses antipsychotic activity and antidepressant- or anxiolytic-like effects with potentially reduced liability for extrapyramidal and CNS depressant side effects.

  4. Translational evaluation of JNJ-18038683, a 5-hydroxytryptamine type 7 receptor antagonist, on rapid eye movement sleep and in major depressive disorder.

    PubMed

    Bonaventure, Pascal; Dugovic, Christine; Kramer, Michelle; De Boer, Peter; Singh, Jaskaran; Wilson, Sue; Bertelsen, Kirk; Di, Jianing; Shelton, Jonathan; Aluisio, Leah; Dvorak, Lisa; Fraser, Ian; Lord, Brian; Nepomuceno, Diane; Ahnaou, Abdellah; Drinkenburg, Wilhelmus; Chai, Wenying; Dvorak, Curt; Sands, Steve; Carruthers, Nicholas; Lovenberg, Timothy W

    2012-08-01

    In rodents 5-hydroxytryptamine type 7 (5-HT(7)) receptor blockade has been shown to be effective in models of depression and to increase the latency to rapid eye movement (REM) sleep and decrease REM duration. In the clinic, the REM sleep reduction observed with many antidepressants may serve as a biomarker. We report here the preclinical and clinical evaluation of a 5-HT(7) receptor antagonist, (3-(4-chlorophenyl)-1,4,5,6,7,8-hexahydro-1-(phenylmethyl)pyrazolo[3,4-d]azepine 2-hydroxy-1,2,3-propanetricarboxylate) (JNJ-18038683). In rodents, JNJ-18038683 increased the latency to REM sleep and decreased REM duration, and this effect was maintained after repeated administration for 7 days. The compound was effective in the mouse tail suspension test. JNJ-18038683 enhanced serotonin transmission, antidepressant-like behavior, and REM sleep suppression induced by citalopram in rodents. In healthy human volunteers JNJ-18038683 prolonged REM latency and reduced REM sleep duration, demonstrating that the effect of 5-HT(7) blockade on REM sleep translated from rodents to humans. Like in rats, JNJ-18038683 enhanced REM sleep suppression induced by citalopram in humans, although a drug-drug interaction could not be ruled out. In a double-blind, active, and placebo-controlled clinical trial in 225 patients suffering from major depressive disorder, neither treatment with pharmacologically active doses of JNJ-18038683 or escitalopram separated from placebo, indicating a failed study lacking assay sensitivity. Post hoc analyses using an enrichment window strategy, where all the efficacy data from sites with an implausible high placebo response [placebo group Montgomery-Åsberg Depression Rating Scale (MADRS) < = 12] and from sites with no placebo response (MADRS > = 28) are removed, there was a clinically meaningful difference between JNJ-18038683 and placebo. Further clinical studies are required to characterize the potential antidepressant efficacy of JNJ-18038683.

  5. 5-Hydroxytryptamine (serotonin)2A receptors in rat anterior cingulate cortex mediate the discriminative stimulus properties of d-lysergic acid diethylamide.

    PubMed

    Gresch, Paul J; Barrett, Robert J; Sanders-Bush, Elaine; Smith, Randy L

    2007-02-01

    d-Lysergic acid diethylamide (LSD), an indoleamine hallucinogen, produces profound alterations in mood, thought, and perception in humans. The brain site(s) that mediates the effects of LSD is currently unknown. In this study, we combine the drug discrimination paradigm with intracerebral microinjections to investigate the anatomical localization of the discriminative stimulus of LSD in rats. Based on our previous findings, we targeted the anterior cingulate cortex (ACC) to test its involvement in mediating the discriminative stimulus properties of LSD. Rats were trained to discriminate systemically administered LSD (0.085 mg/kg s.c.) from saline. Following acquisition of the discrimination, bilateral cannulae were implanted into the ACC (AP, +1.2 mm; ML, +/-1.0 mm; DV, -2.0 mm relative to bregma). Rats were tested for their ability to discriminate varying doses of locally infused LSD (0.1875, 0.375, and 0.75 microg/side) or artificial cerebrospinal fluid (n = 3-7). LSD locally infused into ACC dose-dependently substituted for systemically administered LSD, with 0.75 microg/side LSD substituting completely (89% correct). Systemic administration of the selective 5-hydroxytryptamine (serotonin) (5-HT)(2A) receptor antagonist R-(+)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenylethyl)]-4-piperidine-methanol (M100907; 0.4 mg/kg) blocked the discriminative cue of LSD (0.375 microg/side) infused into ACC (from 68 to 16% drug lever responding). Furthermore, M100907 (0.5 microg/microl/side) locally infused into ACC completely blocked the stimulus effects of systemic LSD (0.04 mg/kg; from 80 to 12% on the LSD lever). Taken together, these data indicate that 5-HT(2A) receptors in the ACC are a primary target mediating the discriminative stimulus properties of LSD.

  6. 5-Hydroxytryptamine2C receptor contribution to m-chlorophenylpiperazine and N-methyl-beta-carboline-3-carboxamide-induced anxiety-like behavior and limbic brain activation.

    PubMed

    Hackler, Elizabeth A; Turner, Greg H; Gresch, Paul J; Sengupta, Saikat; Deutch, Ariel Y; Avison, Malcolm J; Gore, John C; Sanders-Bush, Elaine

    2007-03-01

    Activation of 5-hydroxytryptamine2C (5-HT(2C)) receptors by the 5-HT(2) receptor agonist m-chlorophenylpiperazine (m-CPP) elicits anxiety in humans and anxiety-like behavior in animals. We compared the effects of m-CPP with the anxiogenic GABA(A) receptor inverse agonist N-methyl-beta-carboline-3-carboxamide (FG-7142) on both anxiety-like behavior and regional brain activation using functional magnetic resonance imaging (fMRI) in the rat. We also determined whether the selective 5-HT(2C) receptor antagonist SB 242084 [6-chloro-2,3-dihydro-5-methyl-N-[6-[(2-methyl-3-pyridinyl)oxy]-3-pyridinyl]-1H-indole-1-carboxyamide dihydrochloride] would blunt m-CPP or FG-7142-induced neuronal activation. Both m-CPP (3 mg/kg i.p.) and FG-7142 (10 mg/kg i.p.) elicited anxiety-like behavior when measured in the social interaction test, and pretreatment with SB 242084 (1 mg/kg i.p.) completely blocked the behavioral effects of both anxiogenic drugs. Regional brain activation in vivo in response to anxiogenic drug challenge was determined by blood oxygen level-dependent (BOLD) fMRI using a powerful 9.4T magnet. Region of interest analyses revealed that m-CPP and FG-7142 significantly increased BOLD signals in brain regions that have been linked to anxiety, including the amygdala, dorsal hippocampus, and medial hypothalamus. These BOLD signal increases were blocked by pretreatment with SB 242084. In contrast, injection of m-CPP and FG-7142 resulted in BOLD signal decreases in the medial prefrontal cortex that were not blocked by SB 242084. In conclusion, the brain activation signals produced by anxiogenic doses of both m-CPP and FG-7142 are mediated at least partially by the 5-HT(2C) receptor, indicating that this receptor is a key component in anxiogenic neural circuitry.

  7. Effects of serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibition plus 5-HT(2A) receptor antagonism on the firing activity of norepinephrine neurons.

    PubMed

    Szabo, Steven T; Blier, Pierre

    2002-09-01

    YM992 [(S)-2-[[(7-fluoro-4-indanyl)oxy]methyl]morpholine monohydrochloride] is a selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitor (SSRI) and a potent 5-HT(2A) antagonist. The aim of the present study was to assess, using in vivo extracellular unitary recordings, the effect of acute and sustained administration of YM992 (40 mg kg(-1) day(-1) s.c., using osmotic minipumps) on the spontaneous firing activity of locus coeruleus (LC) norepinephrine (NE) neurons. Acute intravenous injection of YM992 (4 mg kg(-1)) significantly decreased NE neuron firing activity by 29% and blocked the inhibitory effect of a subsequent injection of the 5-HT(2) agonist DOI [1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride]. A 2-day treatment with YM992 decreased the firing rate of NE neurons by 66%, whereas a partial recovery was observed after a 7-day treatment and a complete one after a 21-day treatment. Following the injection of the alpha(2)-adrenoceptor antagonist idazoxan (1 mg kg(-1) i.v.), NE neuron firing was equalized in controls and 2-day YM992-treated rats. This put into evidence an increased degree of activation of alpha(2)-adrenergic autoreceptors in the treated rats. The suppressant effect of the alpha(2)-adrenoceptor agonist clonidine was significantly decreased in long-term YM992-treated rats. The recovery of LC firing activity after long-term YM992 administration could thus be explained by a decreased sensitivity of alpha(2)-adrenergic autoreceptors. Sustained SSRI administration leads to a gradual reduction of the firing activity of NE neurons during long-term administration, whereas YM992 produced opposite effects. The exact basis for the increased synaptic availability of NE by YM992 remains to be elucidated. This NE activity, resulting from 5-HT reuptake inhibition plus 5-HT(2A) receptor antagonism, might confer additional benefits in affective and anxiety disorders.

  8. Selective Recognition of 5-Hydroxytryptamine and Dopamine on a Multi-Walled Carbon Nanotube-Chitosan Hybrid Film-Modified Microelectrode Array

    PubMed Central

    Xu, Huiren; Wang, Li; Luo, Jinping; Song, Yilin; Liu, Juntao; Zhang, Song; Cai, Xinxia

    2015-01-01

    It is difficult to determine dopamine (DA) and 5-hydroxytryptamine (5-HT) accurately because of the interference of ascorbic acid (AA) in vitro, which has a high concentration and can be oxidized at a potential close to DA and 5-HT at a conventional electrode, combined with the overlapping voltammetric signal of DA and 5-HT at a bare electrode. Herein, chitosan (CS) was used as a stabilizing matrix by electrochemical reaction, and multi-walled carbon nanotubes (MWCNTs) were modified onto the microelectrode array (MEA). The CS-MWCNT hybrid film-modified MEA was quite effective at simultaneously recognizing these species in a mixture and resolved the overlapping anodic peaks of AA, DA and 5-HT into three well-defined oxidation peaks in differential pulse voltammetry (DPV) at −80 mV, 105 mV and 300 mV (versus Ag|AgCl), respectively. The linear responses were obtained in the range of 5 × 10−6 M to 2 × 10−4 M for DA (r = 0.996) and in the range of 1 × 10−5 M to 3 × 10−4 M for 5-HT (r = 0.999) using the DPV under the presence of a single substance. While DA coexisted with 5-HT in the interference of 3 × 10−4 M AA, the linear responses were obtained in the range of 1 × 10−5 M to 3 × 10−4 M for selective molecular recognition of DA (r = 0.997) and 5-HT (r = 0.997) using the DPV. Therefore, this proposed MEA was successfully used for selective molecular recognition and determination of DA and 5-HT using the DPV, which has a potential application for real-time determination in vitro experiments. PMID:25580900

  9. [Effects of Chinese herbal medicines for regulating liver qi on expression of 5-hydroxytryptamine 3B receptor in hypothalamic tissues of rats with anger emotion].

    PubMed

    Ge, Qing-fang; Zhang, Hui-yun

    2011-08-01

    To explore the central mechanisms of anger emotion and the effects of Chinese herbal medicines for regulating liver qi on the anger emotion and the expression level of 5-hydroxytryptamine 3B receptor (5-HT3BR) in rat hypothalamus. Rat models of anger-in or anger-out emotions were prepared by the methods of resident intruder paradigm. There were five groups in this study: control, anger-in model, Jingqianshu Granule-treated anger-in, anger-out model and Jingqianping Granule-treated anger-out groups. The treatment groups were orally given Jingqianshu granules and Jingqianping granules respectively, and the model groups and the normal control group were given sterile water. Open-field test and sucrose preference test were used to evaluate behavioristics of the rats. Semi-quantitative reverse transcription-polymerase chain reaction and Western blot methods were used to detect the expression levels of 5-HT3BR mRNA and protein in the rat hypothalamus. The expression of 5-HT3BR in hypothalamus of anger-in model rats increased obviously (P<0.01) and that of anger-out model rats decreased obviously (P<0.01) compared with the normal control group. Compared with the model group, the expressions of 5-HT3BR in the treatment groups were significantly improved (P<0.01) after treatment, and recovered to normal level. The anger-in stimulation obviously increases hypothalamic 5-HT3BR expression and the anger-out emotion can obviously reduce its expression. Chinese herbal medicines for regulating liver qi may treat anger emotion in rats by improving the hypothalamic 5-HT3BR protein and gene expression levels.

  10. Protein kinase mediated upregulation of endothelin A, endothelin B and 5-hydroxytryptamine 1B/1D receptors during organ culture in rat basilar artery

    PubMed Central

    Hansen-Schwartz, Jacob; Svensson, Carl-Lennart; Xu, Cang-Bao; Edvinsson, Lars

    2002-01-01

    Organ culture has been shown to upregulate both endothelin (ET) and 5-hydroxytryptamine 1B/1D (5-HT1B/1D) receptors in rat cerebral arteries. The purpose of the present study was to investigate the involvement of protein kinases, especially protein kinases C (PKC) and A (PKA) in this process. The effect of inhibiting protein kinases during organ culture with staurosporine (unspecific protein kinase inhitor), RO 31-7549 (specific inhibitor of classical PKC's) and H 89 (specific inhibitor of PKA) was examined using in vitro pharmacological examination of cultured vessel segments with ET-1 (unspecific ETA and ETB agonist), S6c (specific ETB agonist) and 5-CT (5-HT1 agonist). Levels of mRNA coding for the ETA, ETB, 5-HT1B and 5-HT1D receptors were analysed using real-time RT–PCR. Classical PKC's are critically involved in the appearance of the ETB receptor; co-culture with RO 31-7549 abolished the contractile response (6.9±1.8%) and reduced the ETB receptor mRNA by 44±4% as compared to the cultured control. Correlation between decreased ETB receptor mRNA and abolished contractile function indicates upstream involvement of PKC. Inhibition of PKA generally had an enhancing effect on the induced changes giving rise to a 7–25% increase in Emax in response to ET-1, S6c and 5-CT as compared to the cultured control. Staurosporine inhibited the culture induced upregulation of the response of both the ETA and the 5-HT1B/1D receptors, but had no significant effect on the mRNA levels of these receptors. This lack of correlation indicates an additional downstream involvement of protein kinases. PMID:12183337

  11. Sucrose preload reduces snacking after mild mental stress in healthy participants as a function of 5-hydroxytryptamine transporter gene promoter polymorphism.

    PubMed

    Markus, C Rob; Jonkman, Lisa M; Capello, Aimee; Leinders, Sacha; Hüsch, Fabian

    2015-01-01

    Brain serotonin (5-hydroxytryptamine, 5-HT) dysfunction is considered to promote food intake and eating-related disturbances, especially under stress or negative mood. Vulnerability for 5-HT disturbances is considered to be genetically determined, including a short (S) allele polymorphism in the serotonin transporter gene (5-HTTLPR) that is associated with lower serotonin function. Since 5-HT function may be slightly increased by carbohydrate consumption, S-allele 5-HTTLPR carriers in particular may benefit from a sugar-preload due to their enhanced 5-HT vulnerability. The aim of the current study was to investigate whether a sugar-containing preload may reduce appetite and energy intake after exposure to stress to induce negative mood, depending on genetic 5-HT vulnerability. From a population of 771 healthy young male and female genotyped college students 31 S/S carriers (8 males, 23 females) and 26 long allele (L/L) carriers (9 males, 17 females) (mean ± S.D. 22 ± 1.6 years; body mass index, BMI, 18-33 kg/m(2)) were monitored for changes in appetite and snacking behavior after stress exposure. Results revealed an increased energy intake after mild mental stress (negative mood) mainly for high-fat sweet foods, which was significantly greater in S/S carriers, and only in these genotypes this intake was significantly reduced by a sucrose-containing preload. Although alternative explanations are possible, it is suggested that S/S participants may have enhanced brain (hypothalamic) 5-HT responsiveness to food that makes them more susceptible to the beneficial satiation effects of a sucrose-preload as well as to the negative effects of mild mental stress on weight gain.

  12. Selective recognition of 5-hydroxytryptamine and dopamine on a multi-walled carbon nanotube-chitosan hybrid film-modified microelectrode array.

    PubMed

    Xu, Huiren; Wang, Li; Luo, Jinping; Song, Yilin; Liu, Juntao; Zhang, Song; Cai, Xinxia

    2015-01-08

    It is difficult to determine dopamine (DA) and 5-hydroxytryptamine (5-HT) accurately because of the interference of ascorbic acid (AA) in vitro, which has a high concentration and can be oxidized at a potential close to DA and 5-HT at a conventional electrode, combined with the overlapping voltammetric signal of DA and 5-HT at a bare electrode. Herein, chitosan (CS) was used as a stabilizing matrix by electrochemical reaction, and multi-walled carbon nanotubes (MWCNTs) were modified onto the microelectrode array (MEA). The CS-MWCNT hybrid film-modified MEA was quite effective at simultaneously recognizing these species in a mixture and resolved the overlapping anodic peaks of AA, DA and 5-HT into three well-defined oxidation peaks in differential pulse voltammetry (DPV) at -80 mV, 105 mV and 300 mV (versus Ag|AgCl), respectively. The linear responses were obtained in the range of 5 × 10(-6) M to 2 × 10(-4) M for DA (r = 0.996) and in the range of 1 × 10(-5) M to 3 × 10(-4) M for 5-HT (r = 0.999) using the DPV under the presence of a single substance. While DA coexisted with 5-HT in the interference of 3 × 10(-4) M AA, the linear responses were obtained in the range of 1 × 10(-5) M to 3 × 10(-4) M for selective molecular recognition of DA (r = 0.997) and 5-HT (r = 0.997) using the DPV. Therefore, this proposed MEA was successfully used for selective molecular recognition and determination of DA and 5-HT using the DPV, which has a potential application for real-time determination in vitro experiments.

  13. The 5-hydroxytryptamine4 receptor agonists prucalopride and PRX-03140 increase acetylcholine and histamine levels in the rat prefrontal cortex and the power of stimulated hippocampal θ oscillations.

    PubMed

    Johnson, David E; Drummond, Elena; Grimwood, Sarah; Sawant-Basak, Aarti; Miller, Emily; Tseng, Elaine; McDowell, Laura L; Vanase-Frawley, Michelle A; Fisher, Katherine E; Rubitski, David M; Stutzman-Engwall, Kim J; Nelson, Robin T; Horner, Weldon E; Gorczyca, Roxanne R; Hajos, Mihaly; Siok, Chester J

    2012-06-01

    5-Hydroxytryptamine (5-HT)(4) receptor agonists reportedly stimulate brain acetylcholine (ACh) release, a property that might provide a new pharmacological approach for treating cognitive deficits associated with Alzheimer's disease. The purpose of this study was to compare the binding affinities, functional activities, and effects on neuropharmacological responses associated with cognition of two highly selective 5-HT(4) receptor agonists, prucalopride and 6,7-dihydro-4-hydroxy-7-isopropyl-6-oxo-N-[3-(piperidin-1-yl)propyl]thieno[2,3-b]pyridine-5-carboxamide (PRX-03140). In vitro, prucalopride and PRX-03140 bound to native rat brain 5-HT(4) receptors with K(i) values of 30 nM and 110 nM, respectively, and increased cAMP production in human embryonic kidney-293 cells expressing recombinant rat 5-HT(4) receptors. In vivo receptor occupancy studies established that prucalopride and PRX-03140 were able to penetrate the brain and bound to 5-HT(4) receptors in rat brain, achieving 50% receptor occupancy at free brain exposures of 330 nM and 130 nM, respectively. Rat microdialysis studies revealed that prucalopride maximally increased ACh and histamine levels in the prefrontal cortex at 5 and 10 mg/kg, whereas PRX-03140 significantly increased cortical histamine levels at 50 mg/kg, failing to affect ACh release at doses lower than 150 mg/kg. In combination studies, donepezil-induced increases in cortical ACh levels were potentiated by prucalopride and PRX-03140. Electrophysiological studies in rats demonstrated that both compounds increased the power of brainstem-stimulated hippocampal θ oscillations at 5.6 mg/kg. These findings show for the first time that the 5-HT(4) receptor agonists prucalopride and PRX-03140 can increase cortical ACh and histamine levels, augment donepezil-induced ACh increases, and increase stimulated-hippocampal θ power, all neuropharmacological parameters consistent with potential positive effects on cognitive processes.

  14. Characterization of the 5-hydroxytryptamine1a receptor-mediated inhibition of forskolin-stimulated adenylate cyclase activity in guinea pig and rat hippocampal membranes.

    PubMed

    De Vivo, M; Maayani, S

    1986-07-01

    The inhibition of forskolin-stimulated adenylate cyclase activity by 5-hydroxytryptamine (5-HT) receptor agonists was measured in guinea pig and rat hippocampal membranes. The results were consistent with the inhibition being mediated by a single, homogeneous population of receptors. In guinea pig hippocampal membranes 8-hydroxy-2-(di-n-propylamino)tetralin, d-lysergic acid diethylamide, 5-HT and buspirone were potent in inhibiting forskolin-stimulated adenylate cyclase activity, with EC50 values of 18, 24, 53 and 146 nM, respectively. Spiperone (Kb = 26 nM) and methiothepin (Kb = 13 nM) were potent competitive antagonists at this receptor whereas ketanserin, a high affinity 5-HT2 receptor ligand, and ICS 205-930, a high affinity peripheral neuronal (M) receptor ligand, were not. In rat hippocampal membranes, 8-hydroxy-2-(di-n-propylamino)tetralin, d-lysergic acid diethylamide, 5-HT and buspirone were potent agonists and exhibited the same rank order of potency as in guinea pig hippocampal membranes. The maximal percentage of inhibition by buspirone was significantly less than the maximal percentage of inhibition by 5-HT in rat membranes, suggesting that it is a partial agonist at this receptor, with an intrinsic activity relative to 5-HT of 0.5. The concentration-response data show that the inhibition of forskolin-stimulated adenylate cyclase activity in guinea pig and rat hippocampal membranes is mediated by a receptor with the characteristics of the 5-HT1A binding site. We propose that the inhibition of adenylate cyclase activity is a functional correlate of this binding site. This response is suitable for measuring activities and affinities of drugs acting at 5-HT1A receptors.

  15. A comparison of 5-hydroxytryptamine receptors mediating contraction in rabbit aorta and dog saphenous vein: evidence for different receptor types obtained by use of selective agonists and antagonists.

    PubMed Central

    Feniuk, W.; Humphrey, P. P.; Perren, M. J.; Watts, A. D.

    1985-01-01

    Using recently available selective agonists and antagonists we have examined further our postulate (Apperley et al., 1980) that 5-hydroxytryptamine (5-HT) mediates contraction of dog saphenous vein via a different 5-HT receptor type from that in the rabbit aorta. In the rabbit isolated aorta, ketanserin and spiperone were potent, specific, competitively-acting antagonists of the contractile effects of 5-HT. In contrast, in the dog isolated saphenous vein neither ketanserin nor spiperone caused any rightward displacement of concentration-response curves to 5-HT although the maximum response was reduced by about 10%. In the rabbit aorta 5-carboxamidotryptamine (5-CONH2-T) was a weak agonist whilst the 5-N,N-dimethyl and 5-N-ethyl derivatives were even weaker or inactive. The contractile effect of 5-CONH2-T in the rabbit aorta was potently and competitively antagonized by ketanserin. In contrast, in the dog saphenous vein 5-CONH2-T and its 5-N,N-dimethyl and 5-N-ethyl derivatives were all potent agonists. The contractile effect of 5-CONH2-T was not markedly affected by ketanserin. The profile of action of ketanserin and spiperone in the rabbit aorta is consistent with the view that 5-HT2 receptors mediate contraction in this preparation. However, the 5-HT receptor mediating contraction in the dog saphenous vein appears to be '5-HT1-like', sharing a number of characteristics with the 5-HT1 recognition site identified from [3H]-5-HT ligand binding studies in brain tissue. PMID:2933110

  16. Brown adipose tissue sympathetic nerve activity is potentiated by activation of 5-hydroxytryptamine (5-HT)1A/5-HT7 receptors in the rat spinal cord

    PubMed Central

    Madden, C. J.; Morrison, S. F.

    2008-01-01

    In urethane-chloralose anesthetized, neuromuscularly blocked, ventilated rats, microinjection of NMDA (12 pmol) into the right fourth thoracic segment (T4) spinal intermediolateral nucleus (IML) immediately increased ipsilateral brown adipose tissue (BAT) sympathetic nerve activity (SNA; peak +492% of control), expired CO2 (+0.1%) heart rate (+48 beats min−1) and arterial pressure (+8 mmHg). The increase in BAT SNA evoked by T4 IML microinjection of NMDA was potentiated when it was administered immediately following a T4 IML microinjection of 5-hydroxytryptamine (5-HT, 100 pmol) or the 5-HT1A/5-HT7 receptor agonist, 8-OH-DPAT (600 pmol), (area under the curve: 184%, and 259% of the NMDA-only response, respectively). In contrast, T4 IML microinjection of the 5-HT2 receptor agonist, DOI (28 pmol) did not potentiate the NMDA-evoked increase in BAT SNA (101% of NMDA-only response). Microinjection into the T4 IML of the selective 5-HT1A antagonist, WAY-100635 (500 pmol), plus the 5-HT7 antagonist, SB-269970 (500 pmol), prevented the 5-HT-induced potentiation of the NMDA-evoked increase in BAT SNA. When administered separately, WAY-100635 (800 pmol) and SB-269970 (800 pmol) attenuated the 8-OH-DPAT-induced potentiation of the NMDA-evoked increase in BAT SNA through effects on the amplitude and duration of the response, respectively. The selective 5-HT2 receptor antagonist, ketanserin (100 pmol), did not attenuate the potentiations of the NMDA-evoked increase in BAT SNA induced by either 5-HT or 8-OH-DPAT. These results demonstrate that activation of 5-HT1A/5-HT7 receptors can act synergistically with NMDA receptor activation within the IML to markedly increase BAT SNA. PMID:18082230

  17. The effect of intraventricular injections of noradrenaline, 5-hydroxytryptamine, acetylcholine and tranylcypromine on the ox (Bos taurus) at different environmental temperatures

    PubMed Central

    Findlay, J. D.; Thompson, G. E.

    1968-01-01

    1. Noradrenaline, 5-hydroxytryptamine (5-HT), acetylcholine and tranylcypromine were injected or infused into the lateral ventricle of the ox. The effects of these drugs on heart and respiration rates, heat production, rectal, skin and hypothalamic temperatures and skin evaporative loss were measured when the animal was exposed to environmental temperatures ranging from -1° C to +30° C. 2. Acetylcholine (0·001-2 mg) had no detectable effect on temperature regulation at 20° C. 3. In small doses (0·005-0·05 mg) 5-HT had no detectable effect. Larger doses (2-5 mg) given in a cold environment (-1° C) also had no effect but the same doses given in warm environments (15-30° C) caused increases in skin temperatures, skin evaporative loss and respiratory rate, and decreases in rectal and hypothalamic temperatures. 4. Infusion of tranylcypromine (0·107 ml./min of a 1 in 50 solution) in a warm environment (20° C) also caused a decrease in rectal temperature after a delay of 1-1½ hr during which no effects were apparent. 5. Noradrenaline (2 mg) had no effect on temperature regulation when injected into animals in a warm environment (30° C). When injected (1 mg) into animals in a cold environment (-1° C) shivering stopped and heat production and rectal and hypothalamic temperatures were decreased. 6. It is concluded that intraventricular 5-HT and noradrenaline both cause a decrease in body temperature, and it is unlikely that central temperature regulation in the ox is mediated only by these two substances. PMID:5636999

  18. Medial hypothalamic 5-hydroxytryptamine (5-HT)1A receptors regulate neuroendocrine responses to stress and exploratory locomotor activity: application of recombinant adenovirus containing 5-HT1A sequences.

    PubMed

    Li, Qian; Holmes, Andrew; Ma, Li; Van de Kar, Louis D; Garcia, Francisca; Murphy, Dennis L

    2004-12-01

    Our previous studies found that serotonin transporter (SERT) knock-out mice showed increased sensitivity to minor stress and increased anxiety-like behavior but reduced locomotor activity. These mice also showed decreased density of 5-hydroxytryptamine (5-HT1A) receptors in the hypothalamus, amygdala, and dorsal raphe. To evaluate the contribution of hypothalamic 5-HT1A receptors to these phenotypes of SERT knock-out mice, two studies were conducted. Recombinant adenoviruses containing 5-HT1A sense and antisense sequences (Ad-1AP-sense and Ad-1AP-antisense) were used to manipulate 5-HT1A receptors in the hypothalamus. The expression of the 5-HT1A genes is controlled by the 5-HT1A promoter, so that they are only expressed in 5-HT1A receptor-containing cells. (1) Injection of Ad-1AP-sense into the hypothalamus of SERT knock-out mice restored 5-HT1A receptors in the medial hypothalamus; this effect was accompanied by elimination of the exaggerated adrenocorticotropin responses to a saline injection (minor stress) and reduced locomotor activity but not by a change in increased exploratory anxiety-like behavior. (2) To further confirm the observation in SERT-/- mice, Ad-1AP-antisense was injected into the hypothalamus of normal mice. The density and the function of 5-HT1A receptors in the medial hypothalamus were significantly reduced in Ad-1AP-antisense-treated mice. Compared with the control group (injected with Ad-track), Ad-1A-antisense-treated mice showed a significant reduction in locomotor activity, but again no changes in exploratory anxiety-like behaviors, tested by elevated plus-maze and open-field tests. Thus, the present results demonstrate that medial hypothalamic 5-HT1A receptors regulate stress responses and locomotor activity but may not regulate exploratory anxiety-like behaviors.

  19. PRX-08066, a novel 5-hydroxytryptamine receptor 2B antagonist, reduces monocrotaline-induced pulmonary arterial hypertension and right ventricular hypertrophy in rats.

    PubMed

    Porvasnik, Stacy L; Germain, Sean; Embury, Jennifer; Gannon, Kimberley S; Jacques, Vincent; Murray, Justin; Byrne, Barry J; Shacham, Sharon; Al-Mousily, Faris

    2010-08-01

    Pulmonary arterial hypertension (PAH) is a life-threatening disease that results in right ventricular failure. 5-((4-(6-Chlorothieno[2,3-d]pyrimidin-4-ylamino)piperidin-1-yl)methyl)-2-fluorobenzonitrile monofumarate (PRX-08066) is a selective 5-hydroxytryptamine receptor 2B (5-HT2BR) antagonist that causes selective vasodilation of pulmonary arteries. In the current study, the effects of PRX-08066 were assessed by using the monocrotaline (MCT)-induced PAH rat model. Male rats received 40 mg/kg MCT or phosphate-buffered saline and were treated orally twice a day with vehicle or 50 or 100 mg/kg PRX-08066 for 5 weeks. Pulmonary and cardiac functions were evaluated by hemodynamics, heart weight, magnetic resonance imaging (MRI), pulmonary artery (PA) morphology, and histology. Cardiac MRI demonstrated that PRX-08066 (100 mg/kg) significantly (P < 0.05) improved right ventricular ejection fraction. PRX-08066 significantly reduced peak PA pressure at 50 and 100 mg/kg (P < 0.05 and < 0.01, respectively) compared with MCT control animals. PRX-08066 therapy also significantly reduced right ventricle (RV)/body weight and RV/left ventricle + septum (P < 0.01 and < 0.001, respectively) compared with MCT-treated animals. Morphometric assessment of pulmonary arterioles revealed a significant reduction in medial wall thickening and lumen occlusion associated with both doses of PRX-08066 (P < 0.01). The 5-HT2BR antagonist PRX-08066 significantly attenuated the elevation in PA pressure and RV hypertrophy and maintained cardiac function. Pulmonary vascular remodeling was also diminished compared with MCT control rats. PRX-08066 prevents the severity of PAH in the MCT rat model.

  20. Isolation-induced aggression in mice: effects of 5-hydroxytryptamine uptake inhibitors and involvement of postsynaptic 5-HT1A receptors.

    PubMed

    Sánchez, C; Hyttel, J

    1994-11-03

    The inhibitory potencies of selective serotonin (5-hydroxytryptamine, 5-HT) uptake inhibitors on isolation-induced aggressive behaviour in male mice were studied. Furthermore, the role of postsynaptic 5-HT1A receptors in the mediation of aggressive behaviour was studied. The selective 5-HT uptake inhibitors, sertraline, floxetine, femoxetine and fluvoxamine, showed weak antiaggressive effects, and citalopram and paroxetine were ineffective. This rank of potencies corresponded with neither uptake inhibitory potencies in vitro nor potentiation of 1-5-hydroxytryptophan (1,5-HTP)-induced motor effects in vivo, as citalopram and paroxetine were among the most potent compounds in these tests. A subeffective dose of 1,5-HTP (110 mumol/kg = 25 mg/kg, s.c.) potentiated the antiaggressive effect of citalopram and paroxetine more than 110 and 1600 times, respectively. The effects of sertraline, fluvoxamine, fluoxetine and femoxetine were only potentiated 3, 36, 4 and 16 times, respectively. The 5-HT releasing compound fenfluramine inhibited the aggressive behaviour dose dependently, and depletion of 5-HT by treatment with p-chloro-phenylalanine methyl ester attenuated this effect significantly. p-Chloro-phenylalanine methyl ester was ineffective itself, but potentiated the antiaggressive effect of the 5-HT1A receptor agonist, 8-hydroxy-2-(di-n-propylamin)tetralin (8-OH-DPAT). The beta-adrenoceptor/5-HT1A receptor antagonist, (-)-penbutolol, reversed the antiaggressive effects of 8-OHDPAT. In conclusion, selective 5-HT uptake inhibitors act in different ways on isolation-induced aggressive behaviour, and postsynaptic 5-HT1A receptors are involved in mediating the aggressive behaviour.

  1. Pharmacological characterization of 5-hydroxytryptamine3 receptors in murine brain and ileum using the novel radioligand [3H]RS-42358-197: evidence for receptor heterogeneity.

    PubMed

    Bonhaus, D W; Wong, E H; Stefanich, E; Kunysz, E A; Eglen, R M

    1993-11-01

    Previous studies have demonstrated species-specific differences in 5-hydroxytryptamine3 (5-HT3) receptors, but unequivocal evidence of 5-HT3 receptor subtypes, within a species, has not yet been obtained. The purpose of the current study was to test for heterogeneity in 5-HT3 receptors in murine tissues. 5-HT3 receptors in membranes derived from brain cerebral cortex of CD-1, C57Bl/6, and Swiss Webster mice and ileum of CD-1 mice were labeled with the 5-HT3 receptor antagonist [3H]RS-42358-197. Structurally diverse competing ligands were then used to characterize the binding site. [3H]RS-42358-197 bound with similar affinity in each of the cortical tissues (mean KD = 0.14 nM; range, 0.06-0.32 nM) but bound with lower affinity in ileal tissue (2.5 nM). The density of sites labeled with [3H]RS-42358-197 ranged from 10.4 fmol/mg of protein in Swiss Webster mouse cortex to 44.2 fmol/mg of protein in Sprague-Dawley rat cortex. Displacing ligands produced a pharmacologic profile of the [3H]RS-42358-197 binding site consistent with it being a 5-HT3 receptor: (R)-YM060 > (S)-zacopride > (R)-zacopride > MDL 72222 > 2-methyl-5-HT. However, > or = 10-fold differences in the affinity of certain ligands were found when comparing 5-HT3 binding sites in membranes from cerebral cortex of the different strains of mice and when comparing 5-HT3 binding sites in brain and ileal membranes prepared from the CD-1 mouse strain.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Regulator of calcineurin 1 modulates cancer cell migration in vitro.

    PubMed

    Espinosa, Allan V; Shinohara, Motoo; Porchia, Leonardo M; Chung, Yun Jae; McCarty, Samantha; Saji, Motoyasu; Ringel, Matthew D

    2009-01-01

    Metastasis suppressors and other regulators of cell motility play an important role in tumor invasion and metastases. We previously identified that activation of the G protein coupled receptor 54 (GPR54) by the metastasis suppressor metastin inhibits cell migration in association with overexpression of Regulator of calcineurin 1 (RCAN1), an endogenous regulator of calcineurin. Calcineurin inhibitors also blocked cell migration in vitro and RCAN1 protein levels were reduced in nodal metastases in thyroid cancer. The purpose of the current study was to determine directly if RCAN1 functions as a motility suppressor in vitro. Several cancer cell lines derived from different cancer types with different motility rates were evaluated for RCAN1 expression levels. Using these systems we determined that reduction of endogenous RCAN1 using siRNA resulted in an increase in cancer cell motility while expression of exogenous RCAN1 reduced cell motility. In one cell line with a high migratory rate, the stability of exogenously expressed RCAN1 protein was reduced and was rescued by treatment with a proteasome inhibitor. Finally, overexpression of RCAN1 was associated with an increase in cell adhesion to collagen IV and reduced calcineurin activity. In summary, we have demonstrated that the expression of exogenous RCAN1 reduces migration and alters adhesion; and that the loss of endogenous RCAN1 leads to an increase in migration in the examined cancer cell lines. These results are consistent with a regulatory role for RCAN1 in cancer cell motility in vitro.

  3. Substrate stiffness modulates lung cancer cell migration but not epithelial to mesenchymal transition.

    PubMed

    Shukla, V C; Higuita-Castro, N; Nana-Sinkam, P; Ghadiali, S N

    2016-05-01

    Biomechanical properties of the tumor microenvironment, including matrix/substrate stiffness, play a significant role in tumor evolution and metastasis. Epithelial to Mesenchymal Transition (EMT) is a fundamental biological process that is associated with increased cancer cell migration and invasion. The goal of this study was to investigate (1) how substrate stiffness modulates the migration behaviors of lung adenocarcinoma cells (A549) and (2) if stiffness-induced changes in cell migration correlate with biochemical markers of EMT. Collagen-coated polydimethylsiloxane (PDMS) substrates and an Ibidi migration assay were used to investigate how substrate stiffness alters the migration patterns of A549 cells. RT-PCR, western blotting and immunofluorescence were used to investigate how substrate stiffness alters biochemical markers of EMT, that is, E-cadherin and N-cadherin, and the phosphorylation of focal adhesion proteins. Increases in substrate stiffness led to slower, more directional migration but did not alter the biochemical markers of EMT. Interestingly, growth factor (i.e., Transforming Growth Factor-β) stimulation resulted in similar levels of EMT regardless of substrate stiffness. We also observed decreased levels of phosphorylated focal adhesion kinase (FAK) and paxillin on stiffer substrates which correlated with slower cell migration. These results indicate that substrate stiffness modulates lung cancer cell migration via focal adhesion signaling as opposed to EMT signaling.

  4. Wound re-epithelialization: modulating keratinocyte migration in wound healing.

    PubMed

    Raja; Sivamani, K; Garcia, Miki Shirakawa; Isseroff, R Rivkah

    2007-05-01

    An essential feature of a healed wound is the restoration of an intact epidermal barrier through wound epithelialization, also known as re-epithelialization. The directed migration of keratinocytes is critical to wound epithelialization and defects in this function are associated with the clinical phenotype of chronic non-healing wounds. A complex balance of signaling factors and surface proteins are expressed and regulated in a temporospatial manner that promote keratinocyte motility and survival to activate wound re-epithelialization. The majority of this review focuses on the mechanisms that regulate keratinocyte migration in the re-epithelialization process. This includes a review of cell attachments via desmosomes, hemidesmosomes, and integrins, the expression of keratins, the role of growth factors, cytokines and chemokines, eicosanoids, oxygen tension, antimicrobial peptides, and matrix metalloproteinases. Also reviewed are recently emerging novel mediators of keratinocyte motility including the role of electric fields, and signaling via the acetylcholine and beta-adrenergic receptors. These multiple regulators impact the ability of keratinocytes to migrate from the wound edge or other epidermal reservoirs to efficiently re-epithelialize a breach in the integrity of the epidermis. New discoveries will continue to uncover the elegant network of events that result in restoration of epidermal integrity and complete the wound repair process.

  5. Activation of constitutive 5-hydroxytryptamine(1B) receptor by a series of mutations in the BBXXB motif: positioning of the third intracellular loop distal junction and its G(o)alpha protein interactions.

    PubMed Central

    Pauwels, P J; Gouble, A; Wurch, T

    1999-01-01

    Constitutive activity of the recombinant human 5-hydroxytryptamine(1B) (5-HT(1B)) receptor (RC code 2.1.5HT.01.B) was investigated by mutagenesis of the BBXXB motif (in which B represents a basic residue and X a non-basic residue) located in the C-terminal portion of the third intracellular loop. In contrast with wild-type 5-HT(1B) receptors, three receptor mutants (Thr(313)-->Lys, Thr(313)-->Arg and Thr(313)-->Gln) increased their agonist-independent guanosine 5'-[gamma-[(35)S]thio]triphosphate binding response by 26-41%. This activity represented approx. 30% of the maximal response induced by 5-HT and could be reversed by the inverse agonists methiothepin and 3-(3-dimethylaminopropyl)-4-hydroxy-N-(4-pyridin-4-yl phenyl)-benzenamide (GR 55562). Enhanced agonist-independent and agonist-dependent 5-HT(1B) receptor activation was provided by co-expression of a pertussis toxin-resistant rat G(o)alpha Cys(351)-->Ile protein. The wild-type 5-HT(1B) receptor displayed a doubling in basal activity, whereas a spectrum of enhanced basal activities (313-571%) was observed with a series of diverse amino acid substitutions (isoleucine, glycine, asparagine, alanine, lysine, phenylalanine, glutamine and arginine) at the 5-HT(1B) receptor position 313 in the presence of pertussis toxin (100 ng/ml). Consequently, the constitutive 5-HT(1B) receptor activity can be modulated by the mutation of Thr(313), and displays a graded range between 11% and 59% of maximal 5-HT(1B) receptor activation by 5-HT. No clear pattern is apparent in the framework of traditionally cited amino acid characteristics (i.e. residue size, charge or hydrophobicity) to explain the observed constitutive activities. The various amino acid substitutions that yielded enhanced activity are unlikely to make similar intramolecular interactions within the 5-HT(1B) receptor. It is hypothesized that the positioning of the junction between the third intracellular loop and transmembrane domain VI is altered by mutation of

  6. The 5-hydroxytryptamine2A receptor is involved in (+)-norfenfluramine-induced arterial contraction and blood pressure increase in deoxycorticosterone acetate-salt hypertension.

    PubMed

    Ni, Wei; Fink, Gregory D; Watts, Stephanie W

    2007-05-01

    The highly effective anorexigen (+)-fenfluramine was widely used to control body weight until the association with primary pulmonary hypertension and valvular heart disease. (+)-Norfenfluramine is the major hepatic metabolite of (+)-fenfluramine and is primarily responsible for the anorexic effect as well as side effects. We reported that (+)-norfenfluramine causes vasoconstriction and a blood pressure increase in rats with normal blood pressure via the 5-hydroxytryptamine (5-HT)2A receptor. With the knowledge that (+)-norfenfluramine also has affinity for 5-HT2B receptors and that arterial 5-HT2B receptor expression is up-regulated in deoxycorticosterone acetate (DOCA)-salt hypertension, we tested the hypothesis that (+)-norfenfluramine-induced vasoconstriction and pressor effects are potentiated in DOCA-salt hypertensive rats in a 5-HT2 receptor-dependent manner. Contractions of arteries were measured using an isolated tissue bath system or myograph. Mean arterial blood pressure was measured in chronically instrumented conscious rats. Effects of (+)-norfenfluramine in stimulating arterial contraction (leftward shift versus SHAM, aorta, 5.13-fold; renal artery, 1.95-fold; mesenteric resistance artery, 1.77-fold) and raising blood pressure were significantly enhanced in hypertension. In arteries from both normotensive and hypertensive rats, (+)-norfenfluramine-induced contraction in aorta was inhibited by 5-HT2A receptor antagonists, ketanserin and LY53857 (4-isopropyl-7-methyl-9-(2-hydroxy-1-meth ylpropoxycarbonyl)4,6,6a,7,8,9,10,10a-octahydroindolo[4,3-fg]quinoline), but not by the 5-HT2B receptor antagonist, LY272015 [6-chloro-5-methyl-N-(5-quinolinyl)-2,3-dihydro-1H-indole-1-carboxamide]. Ketanserin (3 mg/kg) reduced (+)-norfenfluramine-induced pressor response in both SHAM and DOCA rats. Our results demonstrate that (+)-norfenfluramine-induced arterial contraction and blood pressure increases are potentiated in DOCA-salt hypertensive rats. However, it is the 5

  7. Polymorphisms in the 5-hydroxytryptamine 2A receptor and CytochromeP4502D6 genes synergistically predict fluvoxamine-induced side effects in japanese depressed patients.

    PubMed

    Suzuki, Yutaro; Sawamura, Kazushi; Someya, Toshiyuki

    2006-04-01

    5-Hydroxytryptamine (5-HT) receptors are thought to be associated with the gastrointestinal side effects induced by selective serotonin reuptake inhibitors. CytochromeP450 (CYP) 2D6 may also be associated with the side effects induced by fluvoxamine, since the plasma fluvoxamine concentration depends on a CYP2D6 gene polymorphism. This study investigated whether 5-HT receptor and CYP2D6 gene polymorphisms could predict the occurrence of the side effects. The effects of 5-HT receptor and CYP2D6 gene polymorphisms on the incidence of gastrointestinal side effects induced by fluvoxamine were investigated in 100 depressed outpatients who gave written consent to participate in the study. The patients visited every 2 weeks until the week 12 end point and the fluvoxamine dose was changed in response to their clinical symptoms. All side effects, including the gastrointestinal side effects, were assessed at each visit. Polymerase chain reaction was used to determine A-1438G of the 5-HT2A receptor, C195T and Pro16Ser of the 5-HT3A receptor, Tyr129Ser of the 5-HT3B receptor, and the *5 and *10 alleles of CYP2D6. Both the A-1438G polymorphism of the 5-HT2A receptor gene and the CYP2D6 gene polymorphism had significant effects on the incidence of gastrointestinal side effects. Cox regression was used to analyze the combination effect of the two polymorphisms on the gastrointestinal side effects. Cox regression analysis showed that lower metabolizers (LMs) of CYP2D6 with the G/G genotype of the 5-HT2A A-1438G polymorphism had a 4.242-fold (P = 0.009) and LMs with the A/G genotype had a 4.147-fold (P = 0.004) higher risk of developing gastrointestinal side effects than normal metabolizers with the A/A genotype. The 5-HT3A and 3B gene polymorphisms had no significant effects on the incidence of gastrointestinal side effects. 5-HT2A receptor and CYP2D6 gene polymorphisms had a synergistic effect for the prediction of fluvoxamine-induced gastrointestinal side effects.

  8. 5-Hydroxytryptamine type 2A receptors regulate cyclic AMP accumulation in a neuronal cell line by protein kinase C-dependent and calcium/calmodulin-dependent mechanisms.

    PubMed

    Berg, K A; Clarke, W P; Chen, Y; Ebersole, B J; McKay, R D; Maayani, S

    1994-05-01

    The effects of 5-hydroxytryptamine (5-HT)2A receptor activation on cAMP formation were studied in a cell line derived from embryonic rat cortex (A1A1). 5-HT (EC50 = 0.87 microM) amplified the amount of cAMP formed in response to 5'-N-ethylcarboxamidoadenosine (an adenosine A2 receptor agonist), cholera toxin, and forskolin after 15 min of coincubation in the presence of the phosphodiesterase inhibitor rolipram. This effect of 5-HT was blocked by 10 nM ketanserin as well as by 10 nM spiperone, indicating a response mediated by the 5-HT2A receptor subtype. Similarly, cAMP accumulation was enhanced by coincubation with the protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA) and the calcium ionophore A23187. After exposure to PMA for 24 hr (PKC-depleted cells), 5-HT and A23187 still enhanced cAMP formed in response to forskolin and 5'-N-ethylcarboxamidoadenosine, whereas the amplifying effects of PMA were abolished. Analysis by Western blots and PKC activity measurements revealed that, of three PKC isoforms detected in A1A1 cells (alpha, delta, and epsilon), only the calcium-independent isoform PKC-epsilon remained in membrane fractions after long term PMA treatment. In PKC-depleted cells, 5-HT-mediated amplification was greatly reduced after treatment with the calcium chelator 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (acetoxymethyl)-ester or the calmodulin antagonists calmidazolium and N-(6-aminohexyl)-5-chloro-1-napthalenesulfonamide hydrochloride. In addition, 5-HT-mediated amplification of cAMP accumulation was reduced by the PKC inhibitor staurosporine in normal cells but was unaffected in PKC-depleted cells. In conclusion, these data suggest that 5-HT2A receptor activation can amplify cAMP formation in A1A1 cells by two distinct pathways coupled to the hydrolysis of inositol phosphates, i.e., PKC and calcium/calmodulin.

  9. A behavioural and biochemical study in rats of 5-hydroxytryptamine receptor agonists and antagonists, with observations on structure-activity requirements for the agonists

    PubMed Central

    Green, A.R.; Hall, J.E.; Rees, A.R.

    1981-01-01

    1 The effect of the putative 5-hydroxytryptamine (5-HT) receptor antagonists, methysergide, methergoline, mianserin, cyproheptadine, cinanserin (all at 10 mg/kg), methiothepin (5 mg/kg) and (-)-propranolol (20 mg/kg) on the behavioural responses to tranylcypromine (10 mg/kg) followed 30 min later by L-tryptophan (100 mg/kg) was examined. 2 Methysergide, methergoline, methiothepin and (-)-propranolol inhibited head weaving, forepaw treading and hind-limb abduction. Methysergide and methergoline increased reactivity. In contrast, cypropheptadine, cinanserin and mianserin had no effects on the behaviour. 3 Similar findings were obtained when the behaviours were elicited by administration of tranylcypromine (10 mg/kg) followed by the putative 5-HT receptor agonist, 5-methoxy-N,N-dimethyltryptamine (5-MeODMT) (2 mg/kg). 4 When the behaviours were elicited by the putative 5-HT receptor agonist, quipazine (50 mg/kg), all the drugs effectively inhibited head weaving and forepaw treading. 5 When the dose of cypropheptadine was doubled to 20 mg/kg an inhibition of the tranylcypromine/L-tryptophan induced behaviours was seen. 6 Methiothepin produced a marked inhibition of apomorphine-induced locomotor activity whilst all the others enhanced this response, suggesting that only methiothepin inhibits the 5-HT behaviours by dopamine antagonism and that the increased reactivity seen following tranylcypromine/L-tryptophan after pretreatment with methysergide or methergoline might be due to enhanced dopamine function. 7 Pretreatment with p-chlorophenylalanine resulted in enhanced behavioural responses to both 5-MeODMT and quipazine. 8 Both methergoline and methiothepin decreased the rate of 5-HT synthesis in whole brain but not spinal cord and methergoline decreased spinal cord 5-HIAA concentration. None of the other drugs had any significant effects on the concentration of 5-HT, 5-HIAA or 5-HT synthesis rate in brain or spinal cord. 9 Experiments with compounds structurally related

  10. Inhibitory action of niflumic acid on noradrenaline- and 5-hydroxytryptamine-induced pressor responses in the isolated mesenteric vascular bed of the rat.

    PubMed

    Criddle, D N; de Moura, R S; Greenwood, I A; Large, W A

    1997-03-01

    1. The effects of niflumic acid, an inhibitor of calcium-activated chloride currents, were compared with the actions of the calcium channel blocker nifedipine on noradrenaline- and 5-hydroxytryptamine (5-HT)-induced pressor responses of the rat perfused isolated mesenteric vascular bed. 2. Bolus injections of noradrenaline (1 and 10 nmol) increased the perfusion pressure in a dose-dependent manner. Nifedipine (1 microM) inhibited the increase in pressure produced by 1 nmol noradrenaline by 31 +/- 5%. Niflumic acid (10 and 30 microM) also inhibited the noradrenaline-induced increase in perfusion pressure and 30 microM niflumic acid reduced the pressor response to 1 nmol noradrenaline by 34 +/- 6%. 3. The increases in perfusion elicited by 5-HT (0.3 and 3 nmol) were reduced by niflumic acid (10 and 30 microM) in a concentration-dependent manner and 30 microM niflumic acid inhibited responses to 0.3 and 3 nmol 5-HT by, respectively, 49 +/- 8% and 50 +/- 7%. Nifedipine (1 microM) decreased the pressor response to 3 nmol 5-HT by 44 +/- 9%. 4. In the presence of a combination of 30 microM niflumic acid and 1 microM nifedipine the inhibition of the pressor effects of noradrenaline (10 nmol) and 5-HT (3 nmol) was not significantly greater than with niflumic acid (30 microM) alone. Thus the effects of niflumic acid and nifedipine were not additive. 5. In Ca-free conditions the transient contractions induced by 5-HT (3 nmol) were not reduced by 30 microM niflumic acid, suggesting that this agent does not inhibit calcium release from the intracellular store or the binding of 5-HT to its receptor. 6. Niflumic acid 30 microM did not inhibit the pressor responses induced by KCl (20 and 60 mumol) which were markedly reduced by 1 microM nifedipine. In addition, 1 microM levcromakalim decreased pressor responses produced by 20 mumol KCl. These data suggest that niflumic acid does not block directly calcium channels or activate potassium channels. 7. It is concluded that niflumic

  11. Influence of ambient temperature on the thermoregulatory responses to 5-hydroxytryptamine, noradrenaline and acetylcholine injected into the lateral cerebral ventricles of sheep, goats and rabbits

    PubMed Central

    Bligh, J.; Cottle, W. H.; Maskrey, M.

    1971-01-01

    1. The influences of ambient temperature (Ta) on the thermoregulatory effector activities and the body temperature (Tb) of intraventricular injections into the sheep, goat and rabbit of 5-hydroxytryptamine (5-HT), noradrenaline (NA), acetylcholine (ACh), carbachol and eserine, have been interpreted in terms of a simple neuronal model of the pathways between thermosensors and thermoregulatory effectors. 2. In all three species 5-HT in minimal doses caused a rise in respiratory frequency (RF) and a fall in Tb at high Ta, and a reduction in EMG activity and a fall in Tb at low Ta. These effects could be interpreted as those of an excitatory transmitter acting on the warm receptor—heat loss pathway. 3. In all three species NA caused a reduction in RF and a rise in Tb at high Ta, and a reduction in EMG activity and a fall in Tb at low Ta. These effects are interpreted as those of an inhibitory transmitter acting both on the warm sensor—heat loss pathways and on the cold sensor—heat production pathway. 4. The effects of ACh and the cholinomimetic substances carbachol and eserine are complex and more difficult to interpret. In small doses the effects on the sheep and goat are those of an excitatory transmitter on the cold sensor—heat production pathway. There was an increase in EMG activity and a rise in Tb at low Ta, and a reduction in RF and a rise in Tb at high Ta. At higher dose levels in the goat and at all dose levels in the rabbit these substances had the reverse effects which are attributed to a synaptic block due to the excess of the excitatory substance. 5. The effects of ambient temperature and injected substances upon ear temperature are consistent with the predictions of the model if it is assumed (a) that at high and low ambient temperatures direct thermal effects on ear vessels dominate those of the sympathetic innervation, and (b) that the warm sensor influence is to lower peripheral vasomotor tone, and the cold sensor influence is to increase it

  12. Efficacy and safety of 5-hydroxytryptamine 3 receptor antagonists in irritable bowel syndrome: A systematic review and meta-analysis of randomized controlled trials

    PubMed Central

    Tang, Yurong; Xiong, Wenjie; Shen, Xiaoxue; Jiang, Ling; Lin, Lin

    2017-01-01

    Aim We assessed the efficacy and safety of 5-hydroxytryptamine (5-HT3) receptor antagonists in adults with non-constipated irritable bowel syndrome (IBS) or diarrhea-predominant IBS (IBS-D). Methods We searched PubMed, MEDLINE, EMBASE, and the Cochrane Controlled Trials Register for randomized controlled trials (RCTs) involving adults with non-constipated IBS or IBS-D that compared 5-HT3 receptor antagonists with placebo or other conventional treatment. Dichotomous symptom data were pooled to obtain the relative risk (RR) and 95% confidence intervals (CIs) for improving global IBS symptoms, abdominal pain and abnormal bowel habits, or stool consistency symptoms after therapy, and adverse events, including constipation. Meta- analysis was performed with Mantel Haenszel method using Revman 5.3 software. Results We included 21 RCTs; 16 were high quality (Jadad score ≥ 4). The pooled RR of global IBS symptoms improved by 5-HT3 receptor antagonists versus placebo or mebeverine was 1.56 (95% CI: 1.43–1.71); alosetron, ramosetron, and cilansetron had similar treatment effects. The pooled RR of abdominal pain relieved by 5-HT3 receptor antagonists versus placebo was 1.33 (95% CI: 1.26–1.39). The pooled RR showed that 5-HT3 receptor antagonists improved abnormal bowel habits or stool consistency symptoms (RR = 1.63, 95% CI: 1.33, 1.99). The pooled RR of adverse events following 5-HT3 receptor antagonist treatment was 1.15 (95% CI: 1.08, 1.22). Subgroup analysis indicated that alosetron had a high rate of adverse effects (RR = 1.16, 95% CI: 1.08, 1.25); adverse events following ramosetron treatment were not statistically significantly different. 5-HT3 receptor antagonists were likelier to cause constipation: the pooled RR of constipation developing with 5-HT3 receptor antagonist versus placebo was 3.71 (95% CI: 2.98–4.61). However, constipation was likelier in patients with non-constipated IBS after taking 5-HT3 receptor antagonists than in patients with IBS-D only

  13. The effect of the selective 5-HT1A agonists alnespirone (S-20499) and 8-OH-DPAT on extracellular 5-hydroxytryptamine in different regions of rat brain

    PubMed Central

    Casanovas, J M; Lésourd, M; Artigas, F

    1997-01-01

    We have examined the effects of the systemic administration of the selective 5-HT1A agonist alnespirone (S-20499) on in vivo 5-hydroxytryptamine (5-HT) release in the dorsal raphe nucleus, the median raphe nucleus and four forebrain areas innervated differentially by both (dorsal striatum, frontal cortex, ventral hippocampus and dorsal hippocampus). Alnespirone (0.1–3 mg kg−1, s.c.) dose-dependently reduced extracellular 5-HT in the six areas examined. In forebrain, the maximal reductions occurred in striatum and frontal cortex (maximal reduction to 23 and 29% of baseline, respectively). Those in dorsal and ventral hippocampus were more moderate (to ca 65% of baseline). In contrast, the decrease in 5-HT elicited in the median raphe nucleus was more marked than that in the dorsal raphe nucleus (to ca 30 and 60% of baseline, respectively). The selective 5-HT1A antagonist WAY-100635 (0.5 mg kg−1, s.c.) prevented the decrease in 5-HT induced by alnespirone (0.3 mg kg−1, s.c.) in frontal cortex. 8-OH-DPAT (0.025, 0.1 and 0.3 mg kg−1, s.c.) also reduced extracellular 5-HT in a regionally-selective manner (e.g., to 32% of baseline in striatum and to 69% in dorsal hippocampus at 0.1 mg kg−1, s.c.). In midbrain, 8-OH-DPAT reduced the dialysate 5-HT slightly more in the median than in the dorsal raphe nucleus at all doses examined. Doses of both compounds close to their respective ED50 values (0.3 mg kg−1 alnespirone, 0.025 mg kg−1 8-OH-DPAT) reduced 5-HT to a comparable extent in all regions examined. However, the reductions attained at higher doses were more pronounced for 8-OH-DPAT. These data show that the reduction of 5-HT release elicited by alnespirone and 8-OH-DPAT is more important in forebrain areas innervated by 5-hydroxytryptaminergic neurones of the dorsal raphe nucleus. This regional selectivity seems unlikely to be accounted for by differences in the sensitivity of 5-HT1A autoreceptors controlling 5-HT release, given

  14. Modulation of endothelial cell migration by ER stress and insulin resistance: a role during maternal obesity?

    PubMed

    Sáez, Pablo J; Villalobos-Labra, Roberto; Westermeier, Francisco; Sobrevia, Luis; Farías-Jofré, Marcelo

    2014-01-01

    Adverse microenvironmental stimuli can trigger the endoplasmic reticulum (ER) stress pathway, which initiates the unfolded protein response (UPR), to restore protein-folding homeostasis. Several studies show induction of ER stress during obesity. Chronic UPR has been linked to different mechanisms of disease in obese and diabetic individuals, including insulin resistance (IR) and impaired angiogenesis. Endothelial cell (EC) migration is an initial step for angiogenesis, which is associated with remodeling of existing blood vessels. EC migration occurs according to the leader-follower model, involving coordinated processes of chemotaxis, haptotaxis, and mechanotaxis. Thus, a fine-tuning of EC migration is necessary to provide the right timing to form the required vessels during angiogenesis. ER stress modulates EC migration at different levels, usually impairing migration and angiogenesis, although different effects may be observed depending on the tissue and/or microenvironment. In the context of pregnancy, maternal obesity (MO) induces IR in the offspring. Interestingly, several proteins associated with obesity-induced IR are also involved in EC migration, providing a potential link with the ER stress-dependent alterations observed in obese individuals. Different signaling cascades that converge on cytoskeleton regulation directly impact EC migration, including the Akt and/or RhoA pathways. In addition, ER is the main intracellular reservoir for Ca(2+), which plays a pivotal role during EC migration. Therefore, ER stress-related alterations in Ca(2+) signaling or Ca(2+) levels might also produce distorted EC migration. However, the above findings have been studied in the context of adult obesity, and no information has been reported regarding the effect of MO on fetal EC migration. Here we summarize the state of knowledge about the possible mechanisms by which ER stress and IR might impact EC migration and angiogenesis in fetal endothelium exposed to MO during

  15. Alkylindole-sensitive receptors modulate microglial cell migration and proliferation

    PubMed Central

    Fung, Susan; Cherry, Allison E.; Xu, Cong; Stella, Nephi

    2015-01-01

    Ligands targeting G protein-coupled receptors (GPCR) expressed by microglia have been shown to regulate distinct components of their activation process, including cell proliferation, migration and differentiation into M1 or M2 phenotypes. Cannabinoids, including the active component of the Cannabis plant, tetrahydrocannabinol (THC), and the synthetic alkylindole (AI) compound, WIN55212-2 (WIN-2), activate two molecularly identified GPCRs: CB1 and CB2. Previous studies reported that WIN-2 activates an additional unknown GPCR that is not activated by plant-derived cannabinoids, and evidence indicates that microglia express these receptors. Detailed studies on the role of AI-sensitive receptors in microglial cell activation were difficult as no selective pharmacological tools were available. Here, three newly-developed AI analogues allowed us to determine if microglia express AI-sensitive receptors and if so, study how they regulate the microglial cell activation process. We found that mouse microglia in primary culture express functional AI-sensitive receptors as measured by radioligand binding and changes in intracellular cAMP levels, and that these receptors control both basal and ATP-stimulated migration. AI analogues inhibit cell proliferation stimulated by macrophage-colony stimulating factor (M-CSF) without affecting basal cell proliferation. Remarkably, AI analogues do not control the expression of effector proteins characteristic of M1 or M2 phenotypes; yet activating microglia with M1 and M2 cytokines reduces the microglial response to AI analogues. Our results suggest that microglia express functional AI-sensitive receptors that control select components of their activation process. Agonists of these novel targets might represent a novel class of therapeutics to influence the microglial cell activation process. PMID:25914169

  16. Modulation of cell spreading and migration by pp125FAK phosphorylation.

    PubMed Central

    Sankar, S.; Mahooti-Brooks, N.; Hu, G.; Madri, J. A.

    1995-01-01

    We provide evidence for both matrix-dependent and pp60v-src tyrosine kinase-dependent modulation of cell migration via tyrosine phosphorylation of pp125FAK, a focal adhesion kinase, thought to be involved in integrin-mediated signaling. Enhanced pp125FAK tyrosine phosphorylation and cell spreading was associated with decreased migration. Cells plated on type I collagen were less spread and exhibited lower levels of pp125FAK tyrosine phosphorylation and faster migration rates compared with cells on fibronectin that were well spread, which exhibited enhanced levels of pp125FAK tyrosine phosphorylation and slower migration rates. Inside-out signaling via expression of pp60v-src or its kinase-negative mutant caused a decrease in cell migration by changing the extent of pp125FAK tyrosine phosphorylation to above or below the levels obtained with control cells plated on fibronectin. Hence, pp125FAK tyrosine phosphorylation appears to play a role in the signaling cascade pathway involved in regulation of extracellular matrix-modulated, integrin-mediated cell migration. Images Figure 1 Figure 2 Figure 3 PMID:7677174

  17. The sites of action of 5-hydroxytryptamine in nerve-muscle preparations from the guinea-pig small intestine and colon

    PubMed Central

    Costa, M.; Furness, J.B.

    1979-01-01

    1 The sites of action of 5-hydroxytryptamine (5-HT) were examined in isolated segments of guinea-pig intestine. Mechanical records were taken from the longitudinal muscle of the ileum and proximal colon and from the circular muscle of the ileum and distal colon. 2 In order to examine direct actions of 5-HT, nerve-mediated responses were blocked with tetrodotoxin (0.2 μg/ml). There was a gradient in the responsiveness of the longitudinal muscle of the ileum; in the proximal ileum it was usually unresponsive, whereas in the distal ileum about 30% of the amplitude of contraction was caused by a direct effect on the muscle. In the circular muscle from all parts of the ileum, direct effects on the muscle were weak or absent. In the distal colon, the circular muscle was almost always unresponsive to direct effects of 5-HT even when concentrations of 5-HT as great as 100 μg/ml were used. All direct actions of 5-HT on intestinal muscle were blocked by methysergide (1 μg/ml), which itself did not affect nerve-mediated responses. 3 Excitatory cholinergic nerves and excitatory and inhibitory nerves which released unidentified substances were all stimulated by 5-HT. The contractions mediated through cholinergic nerves were blocked by hyoscine (0.6 μg/ml). 4 Tachyphylaxis to the action of 5-HT occurred both for effects mediated through nerves and for direct effects on the muscle. Responses returned promptly after 5-HT was washed from the organ bath. 5 While 5-HT blocked its own action on neural receptors, it did not antagonize the stimulation of nicotinic receptors on cholinergic neurones by 1-1 dimethyl-4-phenylpiperazinium iodide (DMPP). Moreover, pentolinium markedly reduced contractions caused by DMPP without significantly affecting responses to 5-HT. In contrast, (+)-tubocurarine, another nicotinic receptor antagonist, was effective in reducing contractions caused by 5-HT. 6 Phenyldiguanide, which has been reported to antagonize the stimulant action of 5-HT on

  18. Inhibitory action of niflumic acid on noradrenaline- and 5-hydroxytryptamine-induced pressor responses in the isolated mesenteric vascular bed of the rat

    PubMed Central

    Criddle, D N; Soares de Moura, R; Greenwood, I A; Large, W A

    1997-01-01

    The effects of niflumic acid, an inhibitor of calcium-activated chloride currents, were compared with the actions of the calcium channel blocker nifedipine on noradrenaline- and 5-hydroxytryptamine (5-HT)-induced pressor responses of the rat perfused isolated mesenteric vascular bed.Bolus injections of noradrenaline (1 and 10 nmol) increased the perfusion pressure in a dose-dependent manner. Nifedipine (1 μM) inhibited the increase in pressure produced by 1 nmol noradrenaline by 31±5%. Niflumic acid (10 and 30 μM) also inhibited the noradrenaline-induced increase in perfusion pressure and 30 μM niflumic acid reduced the pressor response to 1 nmol noradrenaline by 34±6%.The increases in perfusion elicited by 5-HT (0.3 and 3 nmol) were reduced by niflumic acid (10 and 30 μM) in a concentration-dependent manner and 30 μM niflumic acid inhibited responses to 0.3 and 3 nmol 5-HT by, respectively, 49±8% and 50±7%. Nifedipine (1 μM) decreased the pressor response to 3 nmol 5-HT by 44±9%.In the presence of a combination of 30 μM niflumic acid and 1 μM nifedipine the inhibition of the pressor effects of noradrenaline (10 nmol) and 5-HT (3 nmol) was not significantly greater than with niflumic acid (30 μM) alone. Thus the effects of niflumic acid and nifedipine were not additive.In Ca-free conditions the transient contractions induced by 5-HT (3 nmol) were not reduced by 30 μM niflumic acid, suggesting that this agent does not inhibit calcium release from the intracellular store or the binding of 5-HT to its receptor.Niflumic acid 30 μM did not inhibit the pressor responses induced by KCl (20 and 60 μmol) which were markedly reduced by 1 μM nifedipine. In addition, 1 μM levcromakalim decreased pressor responses produced by 20 μmol KCl. These data suggest that niflumic acid does not block directly calcium channels or activate potassium channels.It is concluded that niflumic acid selectively reduces a

  19. [Influence of occupational stress and 5-hydroxytryptamine 2A receptor gene polymorphisms on depression in workers in a thermal power plant].

    PubMed

    Wu, H; Wang, F F; Zhou, W H; Gu, G Z; Yu, S F

    2016-10-20

    Objective: To investigate the association of occupational stress and 5-hydroxytryptamine 2A (5-HT2A) receptor gene polymorphisms with depression. Methods: In November 2010, cluster sampling was used to select 589 workers in a thermal power plant as study subjects. Questionnaires were used to investigate demographic features and occupational stressors. Polymerase chain reaction-restriction fragment length polymorphism was used to detect the genotypes of T102C and A-1438G in 5-HT2A receptor gene in 589 workers. Results: High-level daily hassles (OR=3.013, 95%CI 1.642~5.530) , more negative emotion (OR=4.808, 95% CI 2.662~8.681) , more body needs (OR=1.890, 95% CI 1.034~3.453) , and severe role conflict (OR=1.815, 95% CI 1.002~3.288) were risk factors for depression, while high rewards (OR=0.424, 95% CI 0.226~0.796) was the protective factor against depression (all P<0.05). There were no significant differences in T102C genotype and allele distributions between the groups with and without depression (P>0.05) ; there was a significant difference in A-1438G genotype distribution between the groups with and without depression (χ(2)= 9.573, P<0.05) , while there was no significant difference in A-1438G allele distribution between these groups (P>0.05). The risk of depression in the workers with high-level daily hassles who carried TC genotype (OR= 4.473, 95% CI 1.161~17.238) or CC genotype (OR=5.176, 95% CI 1.367~19.593) of T102C was 4.473 and 5.176 times that in those with low-level daily hassles who carried TT genotype, and the risk of depression in the workers with more negative emotions who carried TC genotype (OR=5.667, 95%CI 1.204~26.673) or CC genotype (OR=8.114, 95% CI 1.747~37.677) of T102C was 5.667 and 8.114 times that in those with less negative emotion who carried TT genotype. The risk of depression in the workers with high-level daily hassles who carried AG genotype (OR=4.505, 95% CI 2.215~9.162) or GG genotype (OR=6.484, 95% CI 2.562~ 16.414) of A-1438G

  20. Higher-order modulations of fs laser pulses for GHz frequency domain photon migration system.

    PubMed

    Lin, Huang-Yi; Cheng, Nanyu; Tseng, Sheng-Hao; Chan, Ming-Che

    2014-02-24

    Except the fundamental modulation frequency, by higher-order-harmonic modulations of mode-locked laser pulses and a simple frequency demodulation circuit, a novel approach to GHz frequency-domain-photon-migration (FDPM) system was reported. With this novel approach, a wide-band modulation frequency comb is available without any external modulation devices and the only electronics to extract the optical attenuation and phase properties at a selected modulation frequency in FDPM systems are good mixers and lock-in devices. This approach greatly expands the frequency range that could be achieved by conventional FDPM systems and suggests that our system could extract much more information from biological tissues than the conventional FDPM systems. Moreover, this demonstration will be beneficial for discerning the minute change of tissue properties.

  1. The highly selective 5-hydroxytryptamine (5-HT)2A receptor antagonist, EMD 281014, significantly increases swimming and decreases immobility in male congenital learned helpless rats in the forced swim test.

    PubMed

    Patel, Jignesh G; Bartoszyk, Gerd D; Edwards, Emmeline; Ashby, Charles R

    2004-04-01

    We examined the effect of the highly selective 5-hydroxytryptamine (5-HT)(2A) receptor antagonist 7-[4-[2-(4-fluoro-phenyl)-ethyl]-piperazine-1-carbonyl]-1H-indole-3-carbonitrile HCl (EMD 281014) in congenital learned helpless male rats in the forced swim test. The administration of EMD-281014 (0.3-30 mg/kg i.p.) to congenital learned helpless rats dose-dependently and significantly (at 10 and 30 mg/kg) decreased immobility and increased swimming compared to vehicle-treated animals. Thus, EMD 281014 produces effects in the forced swim test resembling those of antidepressants.

  2. Multi-factorial modulation of IGD motogenic potential in MSF (migration stimulating factor).

    PubMed

    Ellis, Ian R; Jones, Sarah J; Staunton, David; Vakonakis, Ioannis; Norman, David G; Potts, Jennifer R; Milner, Caroline M; Meenan, Nicola A G; Raibaud, Sophie; Ohea, Go; Schor, Ana M; Schor, Seth L

    2010-09-10

    Migration Stimulating Factor (MSF) is a genetically truncated isoform of fibronectin (Fn). MSF is a potent stimulator of fibroblast migration, whereas full length Fn is devoid of motogenic activity. MSF and Fn contain four IGD motifs, located in the 3rd, 5th, 7th and 9th type I modules; these modules are referred to as (3)FnI, (5)FnI, (7)FnI and (9)FnI, respectively. We have previously reported that mutation of IGD motifs in modules (7)FnI and (9)FnI of MSF is sufficient to completely abolish the motogenic response of target adult skin fibroblasts. We now report that the IGD sequences in (3)FnI and (5)FnI are also capable of exhibiting motogenic activity when present within fragments of MSF. When present within (1-5)FnI, these sequences require the presence of serum or vitronectin for their motogenic activity to be manifest, whereas the IGD sequences in (7)FnI and (9)FnI are bioactive in the absence of serum factors. All MSF and IGD-containing peptides stimulated the phosphorylation of the integrin binding protein focal adhesion kinase (FAK) but did not necessarily affect migration. These results suggest that steric hindrance determines the motogenic activity of MSF and Fn, and that both molecules contain cryptic bioactive fragments.

  3. Modulation of Cell Migration and Invasiveness by Tumor Suppressor TSC2 in Lymphangioleiomyomatosis

    PubMed Central

    Goncharova, Elena A.; Goncharov, Dmitriy A.; Lim, Poay N.; Noonan, Daniel; Krymskaya, Vera P.

    2006-01-01

    The loss of TSC2 function is associated with the pathobiology of lymphangioleiomyomatosis (LAM), which is characterized by the abnormal proliferation, migration, and differentiation of smooth muscle–like cells within the lungs. Although the etiology of LAM remains unknown, clinical and genetic evidence provides support for the neoplastic nature of LAM. The goal of this study was to determine the role of tumor suppressor TSC2 in the neoplastic potential of LAM cells. We show that primary cultures of human LAM cells exhibit increased migratory activity and invasiveness, which is abolished by TSC2 re-expression. We found that TSC2 also inhibits cell migration through its N-terminus, independent of its GTPase-activating protein activity. LAM cells show increased stress fiber and focal adhesion formation, which is attenuated by TSC2 re-expression. The small GTPase RhoA is activated in LAM cells compared with normal human mesenchymal cells. Pharmacologic inhibition of Rho activity abrogates LAM cell migration; RhoA activity was also abolished by TSC2 re-expression or TSC1 knockdown with specific siRNA. These data demonstrate that TSC2 controls cell migration through its N-terminus by associating with TSC1 and regulating RhoA activity, suggesting that TSC2 may play a critical role in modulating cell migration and invasiveness, which contributes to the pathobiology of LAM. PMID:16388022

  4. Gap junctions/hemichannels modulate interkinetic nuclear migration in the forebrain precursors

    PubMed Central

    Liu, Xiuxin; Hashimoto-Torii, Kazue; Torii, Masaaki; Ding, Chen; Rakic, Pasko

    2010-01-01

    During mitotic division in the telencephalic proliferative ventricular zone (VZ), the nuclei of the neural precursors move basally away from the ventricular surface for DNA synthesis, and apically return to the surface for mitotic division; a process known as interkinetic migration or “to-and-fro” nuclear translocation. The cell, which remains attached to the ventricular surface, either continues cycling, or exits the cycle and migrates to the subventricular zone (SVZ) or the developing cortical plate. While gap junctions/hemichannels are known to modulate DNA synthesis via Ca2+ waves, the role of Ca+ oscillations and the mechanism of nuclear translocation in the VZ precursors are unclear. Here we provide evidence that during apical nuclear migration, VZ precursors display dynamic spontaneous Ca2+ transients, which depend on functional gap junctions/hemichannels via ATP release and Ca2+ mobilizing messenger diffusion. Furthermore, we found that blocking gap junctions/hemichannels or shRNA mediated knockdown of connexin 43 (Cx43) retards the apically directed interkinetic nuclear migration accompanied with changes in the nuclear length/width ratio. In addition, we demonstrated that blocking functional gap junctions/hemichannels induces phosphorylation of small GTPase cdc42 in the VZ precursors. The basal phase of interkinetic migration is much slower and appears to be mediated passively by mechanical forces after cell division. Our findings indicate that functional interference with gap junctions/hemichannels during embryonic development may lead to abnormal corticogenesis and dysfunction of the cerebral cortex in adult organisms. PMID:20335455

  5. KCa3.1 Modulates Neuroblast Migration Along the Rostral Migratory Stream (RMS) In Vivo

    PubMed Central

    Turner, Kathryn L.; Sontheimer, Harald

    2014-01-01

    From the subventricular zone (SVZ), neuronal precursor cells (NPCs), called neuroblasts, migrate through the rostral migratory stream (RMS) to become interneurons in the olfactory bulb (OB). Ion channels regulate neuronal migration during development, yet their role in migration through the adult RMS is unknown. To address this question, we utilized Nestin-CreERT2/R26R-YFP mice to fluorescently label neuroblasts in the adult. Patch-clamp recordings from neuroblasts reveal K+ currents that are sensitive to intracellular Ca2+ levels and blocked by clotrimazole and TRAM-34, inhibitors of intermediate conductance Ca2+-activated K+ (KCa3.1) channels. Immunolabeling and electrophysiology show KCa3.1 expression restricted to neuroblasts in the SVZ and RMS, but absent in OB neurons. Time-lapse confocal microscopy in situ showed inhibiting KCa3.1 prolonged the stationary phase of neuroblasts' saltatory migration, reducing migration speed by over 50%. Both migration and KCa3.1 currents could also be inhibited by blocking Ca2+ influx via transient receptor potential (TRP) channels, which, together with positive immunostaining for transient receptor potential canonical 1 (TRPC1), suggest that TRP channels are an important Ca2+ source modulating KCa3.1 activity. Finally, injecting TRAM-34 into Nestin-CreERT2/R26R-YFP mice significantly reduced the number of neuroblasts that reached the OB, suggesting an important role for KCa3.1 in vivo. These studies describe a previously unrecognized protein in migration of adult NPCs. PMID:23585521

  6. Kinesin-5, a mitotic microtubule-associated motor protein, modulates neuronal migration

    PubMed Central

    Falnikar, Aditi; Tole, Shubha; Baas, Peter W.

    2011-01-01

    Kinesin-5 (also called Eg5 or kif11) is a homotetrameric motor protein that functions by modulating microtubule (MT)–MT interactions. In the case of mitosis, kinesin-5 slows the rate of separation of the half-spindles. In the case of the axon, kinesin-5 limits the frequency of transport of short MTs, and also limits the rate of axonal growth. Here we show that experimental inhibition of kinesin-5 in cultured migratory neurons results in a faster but more randomly moving neuron with a shorter leading process. As is the case with axons of stationary neurons, short MT transport frequency is notably enhanced in the leading process of the migratory neuron when kinesin-5 is inhibited. Conversely, overexpression of kinesin-5, both in culture and in developing cerebral cortex, causes migration to slow and even cease. Regions of anti-parallel MT organization behind the centrosome were shown to be especially rich in kinesin-5, implicating these regions as potential sites where kinesin-5 forces may be especially relevant. We posit that kinesin-5 acts as a “brake” on MT–MT interactions that modulates the advance of the entire MT apparatus. In so doing, kinesin-5 regulates the rate and directionality of neuronal migration and possibly the cessation of migration when the neuron reaches its destination. PMID:21411631

  7. Allosteric interactions between the binding sites of receptor agonists and guanine nucleotides: a comparative study of the 5-hydroxytryptamine1A and adenosine A1 receptor systems in rat hippocampal membranes.

    PubMed

    Mahle, C D; Wiener, H L; Yocca, F D; Maayani, S

    1992-12-01

    The ternary complex formed between agonist, receptor and guanine nucleotide binding protein and its destabilization by guanine nucleotides (GN) was utilized to study early events in signal transduction, by characterizing the allosteric interactions between agonist and GN binding to the receptor/guanine nucleotide binding protein, G complex for adenosine A1 and 5-hydroxytryptamine1A receptors. The functional interaction between the ternary complex and GTP was examined by assaying adenylyl cyclase activity. Binding of a full adenosine A1 agonist ([3H]-R-(-)-N6-(2-phenylisopropyl)adenosine), and a full [(+-)-[3H]-8-hydroxydipropylaminotetralin] and partial ([3H]-8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8- azaspirol[4.5]-decane-7,9-dione) 5-hydroxytryptamine1A agonist was examined in relation to the binding of GN. The amount of ternary complex formed depended upon receptor type and drug relative efficacy. The ratio between the drug's EC50 value (adenylyl cyclase) and dissociation constant (binding) was also receptor and drug relative efficacy dependent. 5'-Guanylylimidodiphosphate (100 microM) caused an approximately 50% decrease in the Bmax for all drugs without affecting Kd values. 5'-Guanylylimidodiphosphate and guanosine 5'-O-(3-thiotriphosphate) attenuated [3H]-agonist binding in a concentration-dependent and saturable manner, with IC50 values increased 2- to 6-fold with increasing receptor occupancy. IC50 values were approximately one-tenth lower at the 5-hydroxytryptamine1A receptor than adenosine A1 receptor; similar values were obtained for inhibition of (+-)-[3H]-8-hydroxydipropylaminotetralin and [3H]-8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8- azaspirol[4.5]-decane-7,9-dione binding, suggesting an independence of agonist efficacy. We propose that the stabilization of the ternary complex by hormone binding, measured by Bmax values, is related to drug-relative efficacy, thus the amount of ternary complex available for destabilization by GN is

  8. Kaempferol inhibits vascular smooth muscle cell migration by modulating BMP-mediated miR-21 expression.

    PubMed

    Kim, Kwangho; Kim, Sunghwan; Moh, Sang Hyun; Kang, Hara

    2015-09-01

    Bioflavonoids are known to induce cardioprotective effects by inhibiting vascular smooth muscle cell (VSMC) proliferation and migration. Kaempferol has been shown to inhibit VSMC proliferation. However, little is known about the effect of kaempferol on VSMC migration and the underlying molecular mechanisms. Our studies provide the first evidence that kaempferol inhibits VSMC migration by modulating the BMP4 signaling pathway and microRNA expression levels. Kaempferol activates the BMP signaling pathway, induces miR-21 expression and downregulates DOCK4, 5, and 7, leading to inhibition of cell migration. Moreover, kaempferol antagonizes the PDGF-mediated pro-migratory effect. Therefore, our study uncovers a novel regulatory mechanism of VSMC migration by kaempferol and suggests that miRNA modulation by kaempferol is a potential therapy for cardiovascular diseases.

  9. Mapping the binding site pocket of the serotonin 5-Hydroxytryptamine2A receptor. Ser3.36(159) provides a second interaction site for the protonated amine of serotonin but not of lysergic acid diethylamide or bufotenin.

    PubMed

    Almaula, N; Ebersole, B J; Zhang, D; Weinstein, H; Sealfon, S C

    1996-06-21

    Like other amine neurotransmitters that activate G-protein-coupled receptors, 5-hydroxytryptamine (5-HT) binds to the 5-HT2A receptor through the interaction of its cationic primary amino group with the conserved Asp3.32(155) in transmembrane helix 3. Computational experiments with a 5-HT2A receptor model suggest that the same functional group of 5-hydroxytryptamine also forms a hydrogen bond with the side chain of Ser3.36(159), which is adjacent in space to Asp3.32(155). However, other 5-HT2A receptor ligands like lysergic acid diethylamide (LSD), in which the amine nitrogen is embedded in a heterocycle, or N,N-dimethyl 5-HT, in which the side chain is a tertiary amine, are found in the computational simulations to interact with the aspartate but not with the serine, due mainly to steric hindrance. The predicted difference in the interaction of various ligands in the same receptor binding pocket was tested with site-directed mutagenesis of Ser3.36(159) --> Ala and Ser3.36(159) --> Cys. The alanine substitution led to an 18-fold reduction in 5-HT affinity and the cysteine substitution to an intermediate 5-fold decrease. LSD affinity, in contrast, was unaffected by either mutation. N,N-Dimethyl 5-HT affinity was unaffected by the cysteine mutation and had a comparatively small 3-fold decrease in affinity for the alanine mutant. These findings identify a mode of ligand-receptor complexation that involves two receptor side chains interacting with the same functional group of specific serotonergic ligands. This interaction serves to orient the ligands in the binding pocket and may influence the degree of receptor activation.

  10. Endogenous migration modulators as parent compounds for the development of novel cardiovascular and anti-inflammatory drugs

    PubMed Central

    Poller, Wolfgang; Rother, Madlen; Skurk, Carsten; Scheibenbogen, Carmen

    2012-01-01

    Development of novel cell migration modulators for anti-inflammatory and cardiovascular therapy is a complex task since any modulator will necessarily interfere with a balanced system of physiological regulators directing proper positioning of diverse immune cell types within the body. Whereas this shall serve efficient pathogen elimination, lack of proper control over these processes may result in counterproductive chronic inflammation and progressive tissue injury instead of healing. Prediction of the therapeutic potential or side effects of any migration modulator is not possible based on theoretical considerations alone but needs to be experimentally evaluated in preclinical disease models and by clinical studies. Here, we briefly summarize basic mechanism of cell migration, and groups of synthetic drugs currently in use for migration modulation. We then discuss one fundamental problem encountered with single-target approaches that arises from the complexity of any inflammation, with multiple interacting and often redundant factors being involved. This issue is likely to arise for any class of therapeutic agent (small molecules, peptides, antibodies, regulatory RNAs) addressing a single gene or protein. Against this background of studies on synthetic migration modulators addressing single targets, we then discuss the potential of endogenous proteins as therapeutic migration modulators, or as parent compounds for the development of mimetic drugs. Regulatory proteins of this type commonly address multiple receptors and signalling pathways and act upon the immune response in a phase-specific manner. Based on recent evidence, we suggest investigation of such endogenous migration modulators as novel starting points for anti-inflammatory and cardiovascular drug development. PMID:22035209

  11. Modulation of mesangial cell migration by extracellular matrix components. Inhibition by heparinlike glycosaminoglycans

    SciTech Connect

    Person, J.M.; Lovett, D.H.; Raugi, G.J.

    1988-12-01

    Extension of mesangial cells (MC) into the pericapillary space is a pathologic response seen in several forms of glomerulonephritis. This process may involve both cytoplasmic extension by MC and actual cellular migration. For investigation of whether extracellular matrix factors could modulate this process, the migratory responses of rat MC were quantitatively examined using a cell culture model. Denuding (wounding) a portion of a confluent culture of MC was followed by migration of mesangial cells into the denuded area. The expected proliferative response to this treatment was blocked by irradiation. The migratory response began within 8 hours of wounding and continued for at least 80 hours. The MC migratory response was specifically inhibited in a dose-dependent and reversible manner by heparin and heparinlike glycosaminoglycans (GAGs). Chondroitin sulfates and hyaluronic acid did not significantly inhibit MC migration. Glomerular basement membrane heparinlike GAGs may normally prevent MC extension into the pericapillary space. Changes in the density or composition of these substances during glomerular inflammatory processes could permit the development of MC pericapillary extensions and thereby lead to further alterations in basement membrane integrity.

  12. The palmitoylation state of PMP22 modulates epithelial cell morphology and migration.

    PubMed

    Zoltewicz, Susie J; Lee, Sooyeon; Chittoor, Vinita G; Freeland, Steven M; Rangaraju, Sunitha; Zacharias, David A; Notterpek, Lucia

    2012-12-03

    PMP22 (peripheral myelin protein 22), also known as GAS 3 (growth-arrest-specific protein 3), is a disease-linked tetraspan glycoprotein of peripheral nerve myelin and constituent of intercellular junctions in epithelia. To date, our knowledge of the post-translational modification of PMP22 is limited. Using the CSS-Palm 2.0 software we predicted that C85 (cysteine 85), a highly conserved amino acid located between the second and third transmembrane domains, is a potential site for palmitoylation. To test this, we mutated C85S (C85 to serine) and established stable cells lines expressing the WT (wild-type) or the C85S-PMP22. In Schwann and MDCK (Madin-Darby canine kidney) cells mutating C85 blocked the palmitoylation of PMP22, which we monitored using 17-ODYA (17-octadecynoic acid). While palmitoylation was not necessary for processing the newly synthesized PMP22 through the secretory pathway, overexpression of C85S-PMP22 led to pronounced cell spreading and uneven monolayer thinning. To further investigate the functional significance of palmitoylated PMP22, we evaluated MDCK cell migration in a wound-healing assay. While WT-PMP22 expressing cells were resistant to migration, C85S cells displayed lamellipodial protrusions and migrated at a similar rate to vector control. These findings indicate that palmitoylation of PMP22 at C85 is critical for the role of the protein in modulating epithelial cell shape and motility.

  13. TGFβ2 Differentially Modulates Smooth Muscle Cell Proliferation and Migration in Electrospun Gelatin-Fibrinogen constructs

    PubMed Central

    Ardila, D. C.; Tamimi, E.; Danford, F.L.; Haskett, D. G.; Kellar, R. S.; Doetschman, T.; Vande Geest, J.P.

    2014-01-01

    A main goal of tissue engineering is the development of scaffolds that replace, restore and improve injured tissue. These scaffolds have to mimic natural tissue, constituted by an extracellular matrix (ECM) support, cells attached to the ECM, and signaling molecules such as growth factors that regulate cell function. In this study we created electrospun flat sheet scaffolds using different compositions of gelatin and fibrinogen. Smooth muscle cells (SMCs) were seeded on the scaffolds, and proliferation and infiltration were evaluated. Additionally, different concentrations of Transforming Growth Factor-beta2 (TGFβ2) were added to the medium with the aim of elucidating its effect on cell proliferation, migration and collagen production. Our results demostrated that a scafold with a composition of 80% gelatin-20% fibrinogen is suitable for tissue engineering applications since it promotes cell growth and migration. The addition of TGFβ2 at low concentrations (≤1ng/ml) to the culture medium resulted in an increase in SMC proliferation and scaffold infiltration, and in the reduction of collagen production. In contrast, TGFβ2 at concentrations >1ng/ml inhibited cell proliferation and migration while stimulating collagen production. According to our results TGFβ2 concentration has a differential effect on SMC function and thus can be used as a biochemical modulator that can be beneficial for tissue engineering applications. PMID:25453947

  14. LIM and SH3 protein-1 modulates CXCR2-mediated cell migration.

    PubMed

    Raman, Dayanidhi; Sai, Jiqing; Neel, Nicole F; Chew, Catherine S; Richmond, Ann

    2010-04-19

    The chemokine receptor CXCR2 plays a pivotal role in migration of neutrophils, macrophages and endothelial cells, modulating several biological responses such as angiogenesis, wound healing and acute inflammation. CXCR2 is also involved in pathogenesis of chronic inflammation, sepsis and atherosclerosis. The ability of CXCR2 to associate with a variety of proteins dynamically is responsible for its effects on directed cell migration or chemotaxis. The dynamic network of such CXCR2 binding proteins is termed as "CXCR2 chemosynapse". Proteomic analysis of proteins that co-immunoprecipitated with CXCR2 in neutrophil-like dHL-60 cells revealed a novel protein, LIM and SH3 protein 1 (LASP-1), binds CXCR2 under both basal and ligand activated conditions. LASP-1 is an actin binding cytoskeletal protein, involved in the cell migration. We demonstrate that CXCR2 and LASP-1 co-immunoprecipitate and co-localize at the leading edge of migrating cells. The LIM domain of LASP-1 directly binds to the carboxy-terminal domain (CTD) of CXCR2. Moreover, LASP-1 also directly binds the CTD of CXCR1, CXCR3 and CXCR4. Using a site-directed and deletion mutagenesis approach, Iso323-Leu324 of the conserved LKIL motif on CXCR2-CTD was identified as the binding site for LASP-1. Interruption of the interaction between CXCR2-CTD and LIM domain of LASP-1 by dominant negative and knock down approaches inhibited CXCR2-mediated chemotaxis. Analysis for the mechanism for inhibition of CXCR2-mediated chemotaxis indicated that LASP-1/CXCR2 interaction is essential for cell motility and focal adhesion turnover involving activation of Src, paxillin, PAK1, p130CAS and ERK1/2. We demonstrate here for the first time that LASP-1 is a key component of the "CXCR2 chemosynapse" and LASP-1 interaction with CXCR2 is critical for CXCR2-mediated chemotaxis. Furthermore, LASP-1 also directly binds the CTD of CXCR1, CXCR3 and CXCR4, suggesting that LASP-1 is a general mediator of CXC chemokine mediated chemotaxis

  15. LIM and SH3 Protein -1 Modulates CXCR2-Mediated Cell Migration

    PubMed Central

    Raman, Dayanidhi; Sai, Jiqing; Neel, Nicole F.; Chew, Catherine S.; Richmond, Ann

    2010-01-01

    Background The chemokine receptor CXCR2 plays a pivotal role in migration of neutrophils, macrophages and endothelial cells, modulating several biological responses such as angiogenesis, wound healing and acute inflammation. CXCR2 is also involved in pathogenesis of chronic inflammation, sepsis and atherosclerosis. The ability of CXCR2 to associate with a variety of proteins dynamically is responsible for its effects on directed cell migration or chemotaxis. The dynamic network of such CXCR2 binding proteins is termed as “CXCR2 chemosynapse”. Proteomic analysis of proteins that co-immunoprecipitated with CXCR2 in neutrophil-like dHL-60 cells revealed a novel protein, LIM and SH3 protein 1 (LASP-1), binds CXCR2 under both basal and ligand activated conditions. LASP-1 is an actin binding cytoskeletal protein, involved in the cell migration. Methodology/Principal Findings We demonstrate that CXCR2 and LASP-1 co-immunoprecipitate and co-localize at the leading edge of migrating cells. The LIM domain of LASP-1 directly binds to the carboxy-terminal domain (CTD) of CXCR2. Moreover, LASP-1 also directly binds the CTD of CXCR1, CXCR3 and CXCR4. Using a site-directed and deletion mutagenesis approach, Iso323-Leu324 of the conserved LKIL motif on CXCR2-CTD was identified as the binding site for LASP-1. Interruption of the interaction between CXCR2-CTD and LIM domain of LASP-1 by dominant negative and knock down approaches inhibited CXCR2-mediated chemotaxis. Analysis for the mechanism for inhibition of CXCR2-mediated chemotaxis indicated that LASP-1/CXCR2 interaction is essential for cell motility and focal adhesion turnover involving activation of Src, paxillin, PAK1, p130CAS and ERK1/2. Conclusions/Significance We demonstrate here for the first time that LASP-1 is a key component of the “CXCR2 chemosynapse” and LASP-1 interaction with CXCR2 is critical for CXCR2-mediated chemotaxis. Furthermore, LASP-1 also directly binds the CTD of CXCR1, CXCR3 and CXCR4

  16. Hint1 suppresses migration and invasion of hepatocellular carcinoma cells in vitro by modulating girdin activity.

    PubMed

    Wu, Xue-Song; Bao, Tian-Hao; Ke, Yang; Sun, De-Yun; Shi, Zhi-Tian; Tang, Hao-Ran; Wang, Lin

    2016-11-01

    Histidine triad nucleotide-binding protein 1 (Hint1) is a haploinsufficient tumor suppressor gene. Its role in cancer cell migration has not been previously speculated. In the current study, we examined the expression of Hint1 in metastatic and non-metastatic lymph nodes of hepatocellular carcinoma (HCC) patients and further elucidated the effect of Hint1 expression on girdin expression and phosphorylation of AKT and ERK1/2 and on the migration of HCC cells in vitro. Expression of Hint1 and girdin in primary HCC tissues and metastatic and non-metastatic lymph nodes was determined by RT-PCR assays. HepG2 cells were transfected with plasmid vectors overexpressing Hint1 or small interfering RNA (siRNA) targeting Hint1, girdin, Hint1 plus girdin, or the scrambled RNA. Migration and invasion of HCC cells were examined by wound and Transwell assays. Protein expression was detected by immunofluorescence and immunoblotting assays. RT-PCR assays revealed that the messenger RNA (mRNA) transcript levels of Hint1 were markedly lower than those of primary HCC tissues and non-metastatic lymph nodes (P < 0.01). By contrast, the mRNA transcript levels of girdin were significantly higher than non-metastatic lymph nodes (P < 0.05). Furthermore, siRNA knockdown of HINT1 resulted in a significant increase in the mRNA transcript levels of girdin in HepG2 cells (P < 0.05). Wound assays and Transwell assays showed that Hint1 knockdown by siRNA significantly enhanced the migration and invasion of HepG2 cells compared to HepG2 cells transfected with scrambled siRNA. Hint1 knockdown also led to significantly increased phosphorylation of girdin and AKT in HepG2 cells (P < 0.05), which, however, was effectively aborted by girdin knockdown by siRNA (P < 0.05). Hint1 is downregulated in metastatic lymph nodes and is implicated in migration and invasion of HCC cells in vitro by modulating girdin and AKT expression and phosphorylation. The Hint1-girdin-AKT signaling axis should be

  17. Mutations of L293 in transmembrane two of the mouse 5-hydroxytryptamine3A receptor alter gating and alcohol modulatory actions

    PubMed Central

    Hu, Xiang-Qun; Hayrapetyan, Volodya; Gadhiya, Jay J; Rhubottom, Heather E; Lovinger, David M; Machu, Tina K

    2006-01-01

    The goal of this study was to determine whether mutations of L293 at the 15′ position of TM2 in the 5-HT3A receptor alter macroscopic current kinetics, and if these changes could account for alterations in alcohol modulation. Receptor function was assessed in Xenopus oocytes under voltage-clamp and in HEK293 cells with whole-cell patch-clamp recording and rapid drug application. Examination of responses of L293C and L293S receptors to agonist alone revealed enhanced activation, deactivation, and desensitization rates relative to the wild-type receptor. The L293G mutation produced marked slowing of deactivation and desensitization rates. Increased potency of 5-HT and increased efficacy of the partial agonist, DA, was also observed in these mutant receptors. Ethanol and trichloroethanol (TCEt) enhancement of receptor function was reduced or eliminated in receptors containing L293 mutations to C, G, or S. The L293I mutant receptor retained ethanol and TCEt sensitivity. Ethanol and TCEt enhanced activation rate in the wild-type, but not the L293G and L293S receptors. No relationship was observed between any physicochemical property of the substituted amino acids and the change in alcohol potentiation of function. The changes in receptor-channel properties in the mutant receptors support the idea that the L293 residue has important roles in channel gating. Our findings indicate that loss of allosteric modulation by alcohols is not related in any simple way to changes in channel kinetic properties brought about by L293 mutants. We did not observe any evidence that L293 is part of an alcohol binding site. PMID:16520747

  18. Modulation of intestinal epithelial cell proliferation, migration, and differentiation in vitro by Astragalus polysaccharides.

    PubMed

    Zhang, Chun Li; Ren, Hui Jun; Liu, Meng Meng; Li, Xiao Gai; Sun, De Li; Li, Nan; Ming, Liang

    2014-01-01

    Previous studies have shown that Astragalus polysaccharides (APS) can be used to treat general gastrointestinal disturbances including intestinal mucosal injury. However, the mechanism by which APS mediate this effect is unclear. In the present study, the effects of APS on proliferation, migration, and differentiation of intestinal epithelial cells (IEC-6) were assessed using an in vitro wounding model and colorimetric thiazolyl blue (MTT) assays. The effect of APS on IEC-6 cell differentiation was observed using a light microscope and scanning electron microscope, and the expression of differentiation-specific markers of IEC-6 cells, such as cytokeratin 18 (CK18), alkaline phosphatase (ALP), tight junction protein ZO-2, and sucrase-isomaltase (SI), was determined by immunofluorescence assay (IFA) and real-time PCR. In addition, APS-induced signaling pathways in IEC-6 cells were characterized. Our results indicated that APS significantly enhance migration and proliferation of IEC-6 cells in vitro. APS-treated IEC-6 cells have numerous microvilli on their apical surface and also highly express CK18, ALP, ZO-2, and SI. Moreover, APS-treated IEC-6 cells, in which the activity and expression level of ornithine decarboxylase (ODC) were significantly elevated, also exhibited an increase in cellular putrescine, whereas no significant increase in TGF-β levels was observed. These findings suggest that APS may enhance intestinal epithelial cell proliferation, migration, and differentiation in vitro by stimulating ODC gene expression and activity and putrescine production, independent of TGF-β. Exogenous administration of APS may provide a new approach for modulating intestinal epithelial wound restitution in vivo.

  19. Modulators of estrogen receptor inhibit proliferation and migration of prostate cancer cells.

    PubMed

    Piccolella, Margherita; Crippa, Valeria; Messi, Elio; Tetel, Marc J; Poletti, Angelo

    2014-01-01

    In the initial stages, human prostate cancer (PC) is an androgen-sensitive disease, which can be pharmacologically controlled by androgen blockade. This therapy often induces selection of androgen-independent PC cells with increased invasiveness. We recently demonstrated, both in cells and mice, that a testosterone metabolite locally synthetized in prostate, the 5α-androstane-3β, 17β-diol (3β-Adiol), inhibits PC cell proliferation, migration and invasion, acting as an anti-proliferative/anti-metastatic agent. 3β-Adiol is unable to bind androgen receptor (AR), but exerts its protection against PC by specifically interacting with estrogen receptor beta (ERβ). Because of its potential retro-conversion to androgenic steroids, 3β-Adiol cannot be used "in vivo", thus, the aims of this study were to investigate the capability of four ligands of ERβ (raloxifen, tamoxifen, genistein and curcumin) to counteract PC progression by mimicking the 3β-Adiol activity. Our results demonstrated that raloxifen, tamoxifen, genistein and curcumin decreased DU145 and PC3 cell proliferation in a dose-dependent manner; in addition, all four compounds significantly decreased the detachment of cells seeded on laminin or fibronectin. Moreover, raloxifen, tamoxifen, genistein and curcumin-treated DU145 and PC3 cells showed a significant decrease in cell migration. Notably, all these effects were reversed by the anti-estrogen, ICI 182,780, suggesting that their actions are mediated by the estrogenic pathway, via the ERβ, the only isoform present in these PCs. In conclusion, these data demonstrate that by selectively activating the ERβ, raloxifen, tamoxifen, genistein and curcumin inhibit human PC cells proliferation and migration favoring cell adesion. These synthetic and natural modulators of ER action may exert a potent protective activity against the progression of PC even in its androgen-independent status.

  20. Migration of the subtropical front as a modulator of glacial climate.

    PubMed

    Bard, Edouard; Rickaby, Rosalind E M

    2009-07-16

    Ice cores extracted from the Antarctic ice sheet suggest that glacial conditions, and the relationship between isotopically derived temperatures and atmospheric PCO(2) have been constant over the last 800,000 years of the Late Pleistocene epoch. But independent lines of evidence, such as the extent of Northern Hemisphere ice sheets, sea level and other temperature records, point towards a fluctuating severity of glacial periods, particularly during the more extreme glacial stadials centred around 340,000 and 420,000 years ago (marine isotope stages 10 and 12). Previously unidentified mechanisms therefore appear to have mediated the relationship between insolation, CO(2) and climate. Here we test whether northward migration of the subtropical front (STF) off the southeastern coast of South Africa acts as a gatekeeper for the Agulhas current, which controls the transport of heat and salt from the Indo-Pacific Ocean to the Atlantic Ocean. Using a new 800,000-year record of sea surface temperature and ocean productivity from ocean sediment core MD962077, we demonstrate that during cold stadials (particularly marine isotope stages 10 and 12), productivity peaked and sea surface temperature was up to 6 degrees C cooler than modern temperatures. This suggests that during these cooler stadials, the STF moved northward by up to 7 degrees latitude, nearly shutting off the Agulhas current. Our results, combined with faunal assemblages from the south Atlantic show that variable northwards migration of the Southern Hemisphere STF can modulate the severity of each glacial period by altering the strength of the Agulhas current carrying heat and salt to the Atlantic meridional overturning circulation. We show hence that the degree of northwards migration of the STF can partially decouple global climate from atmospheric partial pressure of carbon dioxide, P CO(2), and help to resolve the long-standing puzzle of differing glacial amplitudes within a consistent range of atmospheric

  1. Modulation of Intestinal Epithelial Cell Proliferation, Migration, and Differentiation In Vitro by Astragalus Polysaccharides

    PubMed Central

    Zhang, Chun Li; Ren, Hui Jun; Liu, Meng Meng; Li, Xiao Gai; Sun, De Li; Li, Nan; Ming, Liang

    2014-01-01

    Previous studies have shown that Astragalus polysaccharides (APS) can be used to treat general gastrointestinal disturbances including intestinal mucosal injury. However, the mechanism by which APS mediate this effect is unclear. In the present study, the effects of APS on proliferation, migration, and differentiation of intestinal epithelial cells (IEC-6) were assessed using an in vitro wounding model and colorimetric thiazolyl blue (MTT) assays. The effect of APS on IEC-6 cell differentiation was observed using a light microscope and scanning electron microscope, and the expression of differentiation-specific markers of IEC-6 cells, such as cytokeratin 18 (CK18), alkaline phosphatase (ALP), tight junction protein ZO-2, and sucrase-isomaltase (SI), was determined by immunofluorescence assay (IFA) and real-time PCR. In addition, APS-induced signaling pathways in IEC-6 cells were characterized. Our results indicated that APS significantly enhance migration and proliferation of IEC-6 cells in vitro. APS-treated IEC-6 cells have numerous microvilli on their apical surface and also highly express CK18, ALP, ZO-2, and SI. Moreover, APS-treated IEC-6 cells, in which the activity and expression level of ornithine decarboxylase (ODC) were significantly elevated, also exhibited an increase in cellular putrescine, whereas no significant increase in TGF-β levels was observed. These findings suggest that APS may enhance intestinal epithelial cell proliferation, migration, and differentiation in vitro by stimulating ODC gene expression and activity and putrescine production, independent of TGF-β. Exogenous administration of APS may provide a new approach for modulating intestinal epithelial wound restitution in vivo. PMID:25157577

  2. Addition of the Neurokinin-1-Receptor Antagonist (RA) Aprepitant to a 5-Hydroxytryptamine-RA and Dexamethasone in the Prophylaxis of Nausea and Vomiting Due to Radiation Therapy With Concomitant Cisplatin

    SciTech Connect

    Jahn, Franziska; Jahn, Patrick; Sieker, Frank; Vordermark, Dirk; Jordan, Karin

    2015-08-01

    Purpose: To assess, in a prospective, observational study, the safety and efficacy of the addition of the neurokinin-1-receptor antagonist (NK1-RA) aprepitant to concomitant radiochemotherapy, for the prophylaxis of radiation therapy–induced nausea and vomiting. Patients and Methods: This prospective observational study compared the antiemetic efficacy of an NK1-RA (aprepitant), a 5-hydroxytryptamine-RA, and dexamethasone (aprepitant regimen) versus a 5-hydroxytryptamine-RA and dexamethasone (control regimen) in patients receiving concomitant radiochemotherapy with cisplatin at the Department of Radiation Oncology, University Hospital Halle (Saale), Germany. The primary endpoint was complete response in the overall phase, defined as no vomiting and no use of rescue therapy in this period. Results: Fifty-nine patients treated with concomitant radiochemotherapy with cisplatin were included in this study. Thirty-one patients received the aprepitant regimen and 29 the control regimen. The overall complete response rates for cycles 1 and 2 were 75.9% and 64.5% for the aprepitant group and 60.7% and 54.2% for the control group, respectively. Although a 15.2% absolute difference was reached in cycle 1, a statistical significance was not detected (P=.22). Furthermore maximum nausea was 1.58 ± 1.91 in the control group and 0.73 ± 1.79 in the aprepitant group (P=.084); for the head-and-neck subset, 2.23 ± 2.13 in the control group and 0.64 ± 1.77 in the aprepitant group, respectively (P=.03). Conclusion: This is the first study of an NK1-RA–containing antiemetic prophylaxis regimen in patients receiving concomitant radiochemotherapy. Although the primary endpoint was not obtained, the absolute difference of 10% in efficacy was reached, which is defined as clinically meaningful for patients by international guidelines groups. Randomized phase 3 studies are necessary to further define the potential role of an NK1-RA in this setting.

  3. Addition of the Neurokinin-1-Receptor Antagonist (RA) Aprepitant to a 5-Hydroxytryptamine-RA and Dexamethasone in the Prophylaxis of Nausea and Vomiting Due to Radiation Therapy With Concomitant Cisplatin.

    PubMed

    Jahn, Franziska; Riesner, Anica; Jahn, Patrick; Sieker, Frank; Vordermark, Dirk; Jordan, Karin

    2015-08-01

    To assess, in a prospective, observational study, the safety and efficacy of the addition of the neurokinin-1-receptor antagonist (NK1-RA) aprepitant to concomitant radiochemotherapy, for the prophylaxis of radiation therapy-induced nausea and vomiting. This prospective observational study compared the antiemetic efficacy of an NK1-RA (aprepitant), a 5-hydroxytryptamine-RA, and dexamethasone (aprepitant regimen) versus a 5-hydroxytryptamine-RA and dexamethasone (control regimen) in patients receiving concomitant radiochemotherapy with cisplatin at the Department of Radiation Oncology, University Hospital Halle (Saale), Germany. The primary endpoint was complete response in the overall phase, defined as no vomiting and no use of rescue therapy in this period. Fifty-nine patients treated with concomitant radiochemotherapy with cisplatin were included in this study. Thirty-one patients received the aprepitant regimen and 29 the control regimen. The overall complete response rates for cycles 1 and 2 were 75.9% and 64.5% for the aprepitant group and 60.7% and 54.2% for the control group, respectively. Although a 15.2% absolute difference was reached in cycle 1, a statistical significance was not detected (P=.22). Furthermore maximum nausea was 1.58 ± 1.91 in the control group and 0.73 ± 1.79 in the aprepitant group (P=.084); for the head-and-neck subset, 2.23 ± 2.13 in the control group and 0.64 ± 1.77 in the aprepitant group, respectively (P=.03). This is the first study of an NK1-RA-containing antiemetic prophylaxis regimen in patients receiving concomitant radiochemotherapy. Although the primary endpoint was not obtained, the absolute difference of 10% in efficacy was reached, which is defined as clinically meaningful for patients by international guidelines groups. Randomized phase 3 studies are necessary to further define the potential role of an NK1-RA in this setting. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Neuroendocrine control of T cell development in mammals: role of growth hormone in modulating thymocyte migration.

    PubMed

    Savino, Wilson

    2007-09-01

    The thymus gland is a primary lymphoid organ, in which bone-marrow-derived T cell precursors undergo differentiation, eventually leading to migration of positively selected cells to the peripheral lymphoid organs. This differentiation occurs along with cell migration in the context of the thymic microenvironment, a three-dimensional network formed by epithelial cells, macrophages, dendritic cells, fibroblasts and extracellular matrix components. A series of data clearly shows that growth hormone (GH) pleiotropically modulates thymic functions. For example, GH upregulates proliferation of thymocytes and thymic epithelial cells. Accordingly, GH-transgenic mice, as well as animals and humans treated with exogenous GH, exhibit an enhanced cellularity in the organ. Growth hormone stimulates the secretion of thymic hormones, cytokines and chemokines by the thymic microenvironment, as well as the production of extracellular matrix proteins, leading to an increase in thymocyte migratory responses and intrathymic traffic of developing T cells. In addition, GH stimulates the in vivo export of thymocytes from the organ, as ascertained by studies with intrathymic injection of GH in normal mice and with GH-transgenic mice. Moreover, since GH is produced by thymocytes and thymic epithelial cells, which express GH receptors, we should consider that, in addition to the classic endocrine pathway, the GH control of the thymus may include an autocrine/paracrine pathway. Finally, since GH promotes a replenishment of the thymus and an increase of thymocyte export, it could be envisioned as a potential adjuvant therapeutic agent in the treatment of immunodeficiencies associated with thymic atrophy.

  5. An MEK-cofilin signalling module controls migration of human T cells in 3D but not 2D environments.

    PubMed

    Klemke, Martin; Kramer, Elisabeth; Konstandin, Mathias H; Wabnitz, Guido H; Samstag, Yvonne

    2010-09-01

    T cells infiltrate peripheral tissues to execute immunosurveillance and effector functions. For this purpose, T cells first migrate on the two-dimensional (2D) surface of endothelial cells to undergo transendothelial migration. Then they change their mode of movement to undergo migration within the three-dimensional (3D)-extracellular matrix of the infiltrated tissue. As yet, no molecular mechanisms are known, which control migration exclusively in either 2D or 3D environments. Here, we describe a signalling module that controls T-cell chemotaxis specifically in 3D environments. In chemotaxing T cells, Ras activity is spatially restricted to the lamellipodium. There, Ras initiates activation of MEK, which in turn inhibits LIM-kinase 1 activity, thereby allowing dephosphorylation of the F-actin-remodelling protein cofilin. Interference with this MEK-cofilin module by either inhibition of MEK or by knockdown of cofilin reduces speed and directionality of chemotactic migration in 3D-extracellular matrices, but not on 2D substrates. This MEK-cofilin module may have an important function in the tissue positioning of T cells during an immune response.

  6. Pharmacological Inhibition of polysialyltransferase ST8SiaII Modulates Tumour Cell Migration

    PubMed Central

    Al-Saraireh, Yousef M. J.; Sutherland, Mark; Springett, Bradley R.; Freiberger, Friedrich; Ribeiro Morais, Goreti; Loadman, Paul M.; Errington, Rachel J.; Smith, Paul J.; Fukuda, Minoru; Gerardy-Schahn, Rita; Patterson, Laurence H.; Shnyder, Steven D.; Falconer, Robert A.

    2013-01-01

    Polysialic acid (polySia), an α-2,8-glycosidically linked polymer of sialic acid, is a developmentally regulated post-translational modification predominantly found on NCAM (neuronal cell adhesion molecule). Whilst high levels are expressed during development, peripheral adult organs do not express polySia-NCAM. However, tumours of neural crest-origin re-express polySia-NCAM: its occurrence correlates with aggressive and invasive disease and poor clinical prognosis in different cancer types, notably including small cell lung cancer (SCLC), pancreatic cancer and neuroblastoma. In neuronal development, polySia-NCAM biosynthesis is catalysed by two polysialyltransferases, ST8SiaII and ST8SiaIV, but it is ST8SiaII that is the prominent enzyme in tumours. The aim of this study was to determine the effect of ST8SiaII inhibition by a small molecule on tumour cell migration, utilising cytidine monophosphate (CMP) as a tool compound. Using immunoblotting we showed that CMP reduced ST8iaII-mediated polysialylation of NCAM. Utilizing a novel HPLC-based assay to quantify polysialylation of a fluorescent acceptor (DMB-DP3), we demonstrated that CMP is a competitive inhibitor of ST8SiaII (Ki = 10 µM). Importantly, we have shown that CMP causes a concentration-dependent reduction in tumour cell-surface polySia expression, with an absence of toxicity. When ST8SiaII-expressing tumour cells (SH-SY5Y and C6-STX) were evaluated in 2D cell migration assays, ST8SiaII inhibition led to significant reductions in migration, while CMP had no effect on cells not expressing ST8SiaII (DLD-1 and C6-WT). The study demonstrates for the first time that a polysialyltransferase inhibitor can modulate migration in ST8SiaII-expressing tumour cells. We conclude that ST8SiaII can be considered a druggable target with the potential for interfering with a critical mechanism in tumour cell dissemination in metastatic cancers. PMID:23951351

  7. Macrophages Modulate Migration and Invasion of Human Tongue Squamous Cell Carcinoma

    PubMed Central

    Pirilä, Emma; Väyrynen, Otto; Sundquist, Elias; Päkkilä, Kaisa; Nyberg, Pia; Nurmenniemi, Sini; Pääkkönen, Virve; Pesonen, Paula; Dayan, Dan; Vered, Marilena; Uhlin-Hansen, Lars; Salo, Tuula

    2015-01-01

    Oral tongue squamous cell carcinoma (OTSCC) has a high mortality rate and the incidence is rising worldwide. Despite advances in treatment, the disease lacks specific prognostic markers and treatment modality. The spreading of OTSCC is dependent on the tumor microenvironment and involves tumor-associated macrophages (TAMs). Although the presence of TAMs is associated with poor prognosis in OTSCC, the specific mechanisms underlying this are still unknown. The aim here was to investigate the effect of macrophages (Mfs) on HSC-3 tongue carcinoma cells and NF-kappaB activity. We polarized THP-1 cells to M1 (inflammatory), M2 (TAM-like) and R848 (imidazoquinoline-treated) type Mfs. We then investigated the effect of Mfs on HSC-3 cell migration and NF-kappaB activity, cytokine production and invasion using several different in vitro migration models, a human 3D tissue invasion model, antibody arrays, confocal microscopy, immunohistochemistry and a mouse invasion model. We found that in co-culture studies all types of Mfs fused with HSC-3 cells, a process which was partially due to efferocytosis. HSC-3 cells induced expression of epidermal growth factor and transforming growth factor-beta in co-cultures with M2 Mfs. Direct cell-cell contact between M2 Mfs and HSC-3 cells induced migration and invasion of HSC-3 cells while M1 Mfs reduced HSC-3 cell invasion. M2 Mfs had an excess of NF-kappaB p50 subunit and a lack of p65 subunits both in the presence and absence of HSC-3 cells, indicating dysregulation and pro-tumorigenic NF-kappaB activation. TAM-like cells were abundantly present in close vicinity to carcinoma cells in OTSCC patient samples. We conclude that M2 Mfs/TAMs have an important role in OTSCC regulating adhesion, migration, invasion and cytokine production of carcinoma cells favouring tumor growth. These results demonstrate that OTSCC patients could benefit from therapies targeting TAMs, polarizing TAM-like M2 Mfs to inflammatory macrophages and modulating NF

  8. Development and application of a sensitive high performance ion-exchange chromatography method for the simultaneous measurement of dopamine, 5-hydroxytryptamine and norepinephrine in microdialysates from the rat brain.

    PubMed

    Heidbreder, C A; Lacroix, L; Atkins, A R; Organ, A J; Murray, S; West, A; Shah, A J

    2001-12-15

    A high performance liquid chromatography (HPLC) method based on cation exchange separation has been developed for the measurement of dopamine (DA), 5-hydroxytryptamine (5-HT) and norepinephrine (NE) in microdialysates. The separation conditions have been optimised for using electrochemical detection. All three bioamines were resolved in less than 22 min using isocratic conditions. The optimum oxidation potential for the three bioamines was found to be +0.4 V vs. in situ Ag/AgCl reference electrode. Linear regression analysis of HPLC-peak area as a function of concentrations in the range 1-50 ng x ml(-1) gave coefficients of correlation between 0.998 and 0.999. The limit of detection for DA, 5-HT and NE was found to be between 50 and 100 pg x ml(-1) with a signal to noise ratio of 3:1. The method has been applied to the simultaneous measurement of the three monoamines in microdialysates from the medial prefrontal cortex under basal conditions and following the administration of the antipsychotic drug clozapine (10 mg x kg(-1) s.c.).

  9. Bi-Module Sensing Device to In Situ Quantitatively Detect Hydrogen Peroxide Released from Migrating Tumor Cells

    PubMed Central

    Yu, Ling; Tian, YunLi; Gao, AnXiu; Shi, ZhuanZhuan; Liu, YingShuai; Li, ChangMing

    2015-01-01

    Cell migration is one of the key cell functions in physiological and pathological processes, especially in tumor metastasis. However, it is not feasible to monitor the important biochemical molecules produced during cell migrations in situ by conventional cell migration assays. Herein, for the first time a device containing both electrochemical sensing and trans-well cell migration modules was fabricated to sensitively quantify biochemical molecules released from the cell migration process in situ. The fully assembled device with a multi-wall carbon nanotube/graphene/MnO2 nanocomposite functionalized electrode was able to successfully characterize hydrogen peroxide (H2O2) production from melanoma A375 cells, larynx carcinoma HEp-2 cells and liver cancer Hep G2 under serum established chemotaxis. The maximum concentration of H2O2 produced from A375, HEp-2 and Hep G2 in chemotaxis was 130±1.3 nM, 70±0.7 nM and 63±0.7 nM, respectively. While the time required reaching the summit of H2O2 production was 3.0, 4.0 and 1.5 h for A375, HEp-2 and Hep G2, respectively. By staining the polycarbonate micropore membrane disassembled from the device, we found that the average migration rate of the A375, HEp-2 and Hep G2 cells were 98±6%, 38±4% and 32 ±3%, respectively. The novel bi-module cell migration platform enables in situ investigation of cell secretion and cell function simultaneously, highlighting its potential for characterizing cell motility through monitoring H2O2 production on rare samples and for identifying underlying mechanisms of cell migration. PMID:26035641

  10. Modulation of integrin α4β1 by ADAM28 promotes lymphocyte adhesion and transendothelial migration.

    PubMed

    McGinn, Owen J; English, William R; Roberts, Stephanie; Ager, Ann; Newham, Peter; Murphy, Gillian

    2011-10-01

    ADAMs (a disintegrin and metalloproteinase) are a family of type I transmembrane glycoproteins related to snake venom metalloproteases and disintegrins. They are regulatory proteins that modulate intercellular adhesion and the bioavailability of growth factors, and have been implicated in many disease states, including cancer, immunity and inflammation. One member of the ADAM family, ADAM28, has been reported to bind to the integrin α4β1 in humans; however, the distribution of ADAM28 and the biological consequences of ADAM28-α4β1 interactions are yet to be fully elucidated. The expression of ADAM28 in human and murine tissues was examined by multiple Affymetrix microarray analyses, real-time RT-PCR (reverse transcription-PCR) and immunohistochemical staining. We found that ADAM28 has a relatively restricted expression pattern in mouse and human and is highly expressed in the B-lymphocyte lineage, including chronic lymphocytic leukaemic B-cells. The murine B-lymphoma line L1-2 and recombinant soluble murine ADAM28 were used to investigate ADAM28-α4β1 interactions. Our data reveal that ADAM28 binding to α4β1 is typical of integrin-ligand interactions, since it is attenuated by anti-functional integrin antibodies, and is enhanced by Mn2+ and the integrin mAb (monoclonal antibody) 9EG7. However, a key finding was that soluble ADAM28 unexpectedly enhanced α4β1-dependent cell adhesion to VCAM-1 (vascular cell adhesion molecule-1). In so doing ADAM28 was able to influence lymphocyte adhesion to, and migration through, endothelial monolayers, suggesting a physiological role for ADAM28 in regulating the specific spatial and temporal transendothelial migration of lymphocytes.

  11. Transspinal direct current stimulation modulates migration and proliferation of adult newly born spinal cells in mice.

    PubMed

    Samaddar, Sreyashi; Vazquez, Kizzy; Ponkia, Dipen; Toruno, Pedro; Sahbani, Karim; Begum, Sultana; Abouelela, Ahmed; Mekhael, Wagdy; Ahmed, Zaghloul

    2017-02-01

    Direct current electrical fields have been shown to be a major factor in the regulation of cell proliferation, differentiation, migration, and survival, as well as in the maturation of dividing cells during development. During adulthood, spinal cord cells are continuously produced in both animals and humans, and they hold great potential for neural restoration following spinal cord injury. While the effects of direct current electrical fields on adult-born spinal cells cultured ex vivo have recently been reported, the effects of direct current electrical fields on adult-born spinal cells in vivo have not been characterized. Here, we provide convincing findings that a therapeutic form of transspinal direct current stimulation (tsDCS) affects the migration and proliferation of adult-born spinal cells in mice. Specifically, cathodal tsDCS attracted the adult-born spinal cells, while anodal tsDCS repulsed them. In addition, both tsDCS polarities caused a significant increase in cell number. Regarding the potential mechanisms involved, both cathodal and anodal tsDCS caused significant increases in expression of brain-derived neurotrophic factor, while expression of nerve growth factor increased and decreased, respectively. In the spinal cord, both anodal and cathodal tsDCS increased blood flow. Since blood flow and angiogenesis are associated with the proliferation of neural stem cells, increased blood flow may represent a major factor in the modulation of newly born spinal cells by tsDCS. Consequently, we propose that the method and novel findings presented in the current study have the potential to facilitate cellular, molecular, and/or bioengineering strategies to repair injured spinal cords.NEW & NOTEWORTHY Our results indicate that transspinal direct current stimulation (tsDCS) affects the migratory pattern and proliferation of adult newly born spinal cells, a cell population which has been implicated in learning and memory. In addition, our results suggest a

  12. cAMP-induced Epac-Rap activation inhibits epithelial cell migration by modulating focal adhesion and leading edge dynamics.

    PubMed

    Lyle, Karen S; Raaijmakers, Judith H; Bruinsma, Wytse; Bos, Johannes L; de Rooij, Johan

    2008-06-01

    Epithelial cell migration is a complex process crucial for embryonic development, wound healing and tumor metastasis. It depends on alterations in cell-cell adhesion and integrin-extracellular matrix interactions and on actomyosin-driven, polarized leading edge protrusion. The small GTPase Rap is a known regulator of integrins and cadherins that has also been implicated in the regulation of actin and myosin, but a direct role in cell migration has not been investigated. Here, we report that activation of endogenous Rap by cAMP results in an inhibition of HGF- and TGFbeta-induced epithelial cell migration in several model systems, irrespective of the presence of E-cadherin adhesion. We show that Rap activation slows the dynamics of focal adhesions and inhibits polarized membrane protrusion. Importantly, forced integrin activation by antibodies does not mimic these effects of Rap on cell motility, even though it does mimic Rap effects in short-term cell adhesion assays. From these results, we conclude that Rap inhibits epithelial cell migration, by modulating focal adhesion dynamics and leading edge activity. This extends beyond the effect of integrin affinity modulation and argues for an additional function of Rap in controlling the migration machinery of epithelial cells.

  13. In-situ calibration: migrating control system IP module calibration from the bench to the storage ring

    SciTech Connect

    Weber, Jonah M.; Chin, Michael

    2002-04-30

    The Control System for the Advanced Light Source (ALS) at Lawrence Berkeley National Lab (LBNL) uses in-house designed IndustryPack(registered trademark) (IP) modules contained in compact PCI (cPCI) crates with 16-bit analog I/O to control instrumentation. To make the IP modules interchangeable, each module is calibrated for gain and offset compensation. We initially developed a method of verifying and calibrating the IP modules in a lab bench test environment using a PC with LabVIEW. The subsequent discovery that the ADCs have significant drift characteristics over periods of days of installed operation prompted development of an ''in-situ'' calibration process--one in which the IP modules can be calibrated without removing them from the cPCI crates in the storage ring. This paper discusses the original LabVIEW PC calibration and the migration to the proposed in-situ EPICS control system calibration.

  14. Plakophilin 2 Affects Cell Migration by Modulating Focal Adhesion Dynamics and Integrin Protein Expression

    PubMed Central

    Koetsier, Jennifer L.; Amargo, Evangeline V.; Todorović, Viktor; Green, Kathleen J.; Godsel, Lisa M.

    2014-01-01

    Plakophilin 2 (PKP2), a desmosome component, modulates the activity and localization of the small GTPase RhoA at sites of cell–cell contact. PKP2 regulates cortical actin rearrangement during junction formation, and its loss is accompanied by an increase in actin stress fibers. We hypothesized that PKP2 may regulate focal adhesion dynamics and cell migration. Here we show that PKP2-deficient cells bind efficiently to the extracellular matrix, but upon spreading display total cell areas ~30% smaller than control cells. Focal adhesions in PKP2-deficient cells are ~2× larger and more stable than in control cells, and vinculin displays an increased time for fluorescence recovery after photobleaching. Furthermore, β4 and β1 integrin protein and mRNA expression is elevated in PKP2-silenced cells. Normal focal adhesion phenotypes can be restored in PKP2-null cells by dampening the RhoA pathway or silencing β1 integrin. However, integrin expression levels are not restored by RhoA signaling inhibition. These data uncover a potential role for PKP2 upstream of β1 integrin and RhoA in integrating cell–cell and cell–substrate contact signaling in basal keratinocytes necessary for the morphogenesis, homeostasis, and reepithelialization of the stratified epidermis. PMID:23884246

  15. FixO3 project results, legacy and module migration to EMSO

    NASA Astrophysics Data System (ADS)

    Lampitt, Richard

    2017-04-01

    The fixed point open ocean observatory network (FixO3) project is an international project aimed at integrating in a single network all fixed point open ocean observatories operated by European organisations and to harmonise and coordinate technological, procedural and data management across the stations. The project is running for four years since September 2013 with 29 partners across Europe and a budget of 7M Euros and is now coming to its final phase. In contrast to several past programmes, the opportunity has arisen to ensure that many of the project achievements can migrate into the newly formed European Multidisciplinary Seafloor and water column Observatory (EMSO) research infrastructure. The final phase of the project will focus on developing a strategy to transfer the results in an efficient way to maintain their relevance and maximise their use. In this presentation, we will highlight the significant achievements of FixO3 over the past three years focussing on the modules which will be transferred to EMSO in the coming 9 months. These include: 1. Handbook of best practices for operating fixed point observatories 2. Metadata catalogue 3. Earth Virtual Observatory (EarthVO) for data visualisation and comparison 4. Open Ocean Observatory Yellow Pages (O3YP) 5. Training material for hardware, data and data products used

  16. Chronic treatment with escitalopram but not R-citalopram translocates Galpha(s) from lipid raft domains and potentiates adenylyl cyclase: a 5-hydroxytryptamine transporter-independent action of this antidepressant compound.

    PubMed

    Zhang, Lanqiu; Rasenick, Mark M

    2010-03-01

    Chronic antidepressant treatment has been shown to increase adenylyl cyclase activity, in part, due to translocation of Galpha(s) from lipid rafts to a nonraft fraction of the plasma membrane where they engage in a more facile stimulation of adenylyl cyclase. This effect holds for multiple classes of antidepressants, and for serotonin uptake inhibitors, it occurs in the absence of the serotonin transporter. In the present study, we examined the change in the amount of Galpha(s) in lipid raft and whole cell lysate after exposing C6 cells to escitalopram. The results showed that chronic (but not acute) escitalopram decreased the content of Galpha(s) in lipid rafts, whereas there was no change in overall Galpha(s) content. These effects were drug dose- and exposure time-dependent. Although R-citalopram has been reported to antagonize some effects of escitalopram, this compound was without effect on Galpha(s) localization in lipid rafts, and R-citalopram did not inhibit these actions of escitalopram. Escitalopram treatment increased cAMP accumulation, and this seemed due to increased coupling between Galpha(s) and adenylyl cyclase. Thus, escitalopram is potent, rapid and efficacious in translocating Galpha(s) from lipid rafts, and this effect seems to occur independently of 5-hydroxytryptamine transporters. Our results suggest that, although antidepressants display distinct affinities for well identified targets (e.g., monoamine transporters), several presynaptic and postsynaptic molecules are probably modified during chronic antidepressant treatment, and these additional targets may be required for clinical efficacy of these drugs.

  17. Sustained desensitization of hypothalamic 5-Hydroxytryptamine1A receptors after discontinuation of fluoxetine: inhibited neuroendocrine responses to 8-hydroxy-2-(Dipropylamino)Tetralin in the absence of changes in Gi/o/z proteins.

    PubMed

    Raap, D K; Garcia, F; Muma, N A; Wolf, W A; Battaglia, G; van de Kar, L D

    1999-02-01

    Long-term exposure to fluoxetine produces a desensitization of hypothalamic postsynaptic 5-hydroxytryptamine (5-HT)1A receptors, indicated by a substantial inhibition of the 5-HT1A receptor-mediated stimulation of oxytocin and adrenocorticotropic hormone (ACTH) secretion. The present study investigated the time course and mechanism of this desensitization after discontinuation of fluoxetine administration. Male rats were injected with saline or fluoxetine (10 mg/kg/day, i.p.) for 14 days and were challenged with a 5-HT1A agonist, [8-hydroxy-2-(dipropylamino)tetralin (8-OH-DPAT) 50 microg/kg, s.c.] 2, 4, 7, 14, 28, or 60 days post-treatment. In control animals, 8-OH-DPAT significantly increased (approximately 15-fold) plasma levels of oxytocin and ACTH. At 2 days post-treatment, oxytocin and ACTH responses to 8-OH-DPAT were reduced by 74% and 68%, respectively. During further withdrawal from fluoxetine, there was a gradual increase in the oxytocin response toward control levels. However, even 60 days after discontinuation of fluoxetine, the oxytocin response was still significantly reduced by 26% compared with controls. In contrast, the suppressed ACTH response to 8-OH-DPAT (a less-sensitive indicator of desensitization) gradually returned to control levels by day 14 of withdrawal from fluoxetine. Interestingly, the sustained reductions in the hormone responses occurred in the absence of reductions in Gz or Gi protein levels in the hypothalamus. Furthermore, this desensitization was sustained in the absence of detectable levels of fluoxetine and norfluoxetine in plasma and brain tissue. These findings suggest that the sustained desensitization of hypothalamic 5-HT1A receptor systems, observed during fluoxetine withdrawal, may be due to altered interactions among the protein components of the 5-HT1A receptor system, rather than their absolute levels.

  18. Platelet 5-hydroxytryptamine (5-HT) transporter and 5-HT2A receptor binding after chronic hypercorticosteronemia, (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane administration or neurotoxin-induced depletion of central nervous system 5-HT in the rat.

    PubMed

    Owens, M J; Ballenger, C A; Knight, D L; Nemeroff, C B

    1996-09-01

    There is considerable evidence that the number of platelet 5-hydroxytryptamine (5-HT) transporter binding sites, as measured by [3H]imipramine binding, are significantly decreased, and platelet 5-HT2 receptor density is increased, in drug-free patients with major depression. To investigate whether these changes in the platelet 5-HT transporter or 5-HT2 receptor sites resulted from known or hypothesized biochemical changes observed in major depression, we examined, in the rat, whether a chronic hyperglucocorticoid state, or decreases or increases in central nervous system 5-HT neurotransmission, altered binding of the selective ligands [3H]citalopram and [125I] (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane to platelet and brain 5-HT transporters and 5-HT2 receptors, respectively. Chronic (6 weeks) hypercorticosteronemia did not alter either brain or platelet 5-HT transporter or 5-HT2A receptor binding. Similarly, 8-week administration of the 5-HT2A/5-HT2C agonist (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane, at a dose which down-regulates brain 5-HT2A/2C receptors, did not alter brain or platelet 5-HT transporters or platelet 5-HT2A receptors. Additionally, para-chloroamphetamine-(11 weeks) or fenfluramine-induced chronic (1.5-10 weeks) depletion of central nervous system 5-HT did not alter platelet 5-HT transporter or 5-HT2A receptor binding. Finally, there was no correlation between the number of 5-HT transporters in brain and platelets in any of the control or treatment groups. These findings suggest that the observed changes in platelet 5-HT transporter and 5-HT2A receptor binding in depressed patients are more apt to be of genetic origin (i.e., trait-dependent) rather than an epiphenomenon of hypercortisolemia or altered central nervous system 5-HT status.

  19. Risperidone-Induced Inactivation and Clozapine-Induced Reactivation of Rat Cortical Astrocyte 5-Hydroxytryptamine7 Receptors: Evidence for In Situ G Protein-Coupled Receptor Homodimer Protomer Cross-Talk

    PubMed Central

    Smith, Carol; Toohey, Nicole; Knight, Jessica A.; Klein, Michael T.

    2011-01-01

    We have reported previously novel drug-induced inactivation and reactivation of human 5-hydroxytryptamine7 (5-HT7) receptors in a recombinant cell line. To explain these novel observations, a homodimer structure displaying protomer-protomer cross-talk was proposed. To determine whether these novel observations and interpretations are due to an artifactual G protein-coupled receptor (GPCR) mechanism unique to the recombinant cell line, we explored the properties of r5-HT7 receptors expressed by cortical astrocytes in primary culture. As in the recombinant cell line, risperidone, 9-OH-risperidone, methiothepin, and bromocriptine were found to potently inactivate r5-HT7 receptors. As in the recombinant cell line, exposure of risperidone-inactivated astrocyte r5-HT7 receptors to competitive antagonists resulted in the reactivation of r5-HT7 receptors. The potencies of the reactivating drugs closely correlated with their affinities for h5-HT7 receptors. These results indicate the novel inactivating and reactivating property of drugs is not due to an artifact of the recombinant cell line expressing h5-HT7 receptors but is an intrinsic property of 5-HT7 receptors in vitro and ex vivo. This evidence suggests that a native (nonmutated) GPCR, in its native membrane environment (cortical astrocyte primary culture), can function as a homodimer with protomer-protomer cross-talk. Homodimers may be a common GPCR structure. The experimental design used in our studies can be used to explore the properties of other GPCRs in their native forms in recombinant cells, primary cultures expressing the endogenous GPCRs, and possibly in vivo. The homodimer structure and protomer-protomer cross-talk offer new avenues of research into receptor dysfunction in disease states and the development of novel drugs. PMID:21062995

  20. Effects of 5-hydroxytryptamine (serotonin) and forskolin on intracellular free calcium in isolated and fura-2 loaded smooth-muscle cells from the anterior byssus retractor (catch) muscle of Mytilus edulis.

    PubMed

    Ishii, N; Simpson, A W; Ashley, C C

    1989-06-01

    Effects of 5-hydroxytryptamine (5-HT) and forskolin on intracellular free calcium concentration [( Ca2+]i) were studied in suspensions of fura-2 loaded smooth-muscle cells from the anterior byssus retractor 'catch' muscle of Mytilus edulis. The successive addition of 5 mM carbachol (CCh) and 100 mM KCl to the suspension evoked a transient elevation of [Ca2+]i from the resting value of 124 +/- 2.7 nM (mean +/- SE, n = 18) to 300-400 nM, which was associated with contraction. The change in [Ca2+]i induced CCh was concentration-dependent with the EC50 of 10(-5) M. The resting [Ca2+]i was unaffected by 10 microM 5-HT. The change in [Ca2+]i induced by 5 mM CCh was suppressed by 5-HT from 167 +/- 14.0 (n = 11) to 124 +/- 14.9 (n = 8) nM whereas that induced by 100 mM KCl was enhanced from 321 +/- 31.9 to 405 +/- 17.6 nM (n = 8). 5-HT applied during the decaying phase of the CCh response caused a rapid decline in [Ca2+]i. In both the responses to CCh and KCl, the falling phase was accelerated by 5-HT. 10 microM forskolin, a potent activator of adenylate cyclase, mimicked the effects of 5-HT as did a membrane-permeant cyclic AMP analogue, 8-parachlorophenylthio cyclic AMP (cpt-cAMP). Application of 100 microM cpt-cAMP partially suppressed the Ca2+i response to CCh and enhanced that to KCl. D-Tubocurarine (500 microM) added during the decaying phase of the response induced by 100 microM CCh, caused a rapid decline in [Ca2+]i similar to that caused by both 5-HT and forskolin.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. DuP 734 [1-(cyclopropylmethyl)-4-(2'(4''-fluorophenyl)-2'-oxoethyl)- piperidine HBr], a sigma and 5-hydroxytryptamine2 receptor antagonist: receptor-binding, electrophysiological and neuropharmacological profiles.

    PubMed

    Tam, S W; Steinfels, G F; Gilligan, P J; Schmidt, W K; Cook, L

    1992-12-01

    It has been suggested that sigma receptor antagonists may be useful as antipsychotic drugs and that 5-hydroxytryptamine (5-HT2) receptor antagonists produce improvements of the negative symptoms of schizophrenia. [1-(Cyclopropylmethyl)-4-(2'-(4''-fluorophenyl)-2'- oxoethyl)-piperidine HBr] (DuP 734) is a novel compound with high affinity for the sigma (Ki = 10 nM) and 5-HT2 (Ki = 15 nM) receptors, but low affinity for dopamine receptors (Ki > 1000 nM) as well as 33 other receptors, ion channels and second messenger systems in vitro. DuP 734 did not inhibit the synaptosomal uptake of dopamine, 5-HT or norepinephrine. Oral administration of DuP 734 potently blocked 5-hydroxy-L-trytophan (5-HTP)-induced head twitch in the rat (ED50 = 6.5 mumol/kg), indicating 5-HT2 antagonist activity. Extracellular single-unit recording studies demonstrated that DuP 734 antagonized the effect of the selective sigma ligand (+)-3-(3-hydroxyphenyl-N-(1-propyl) piperidine [(+)-3-PPP] on dopamine neuronal activity in the substantia nigra of the rat with an ED90 of 3.6 mumol/kg i.v. The sigma receptor agonists (+)-SKF 10,047 and phencyclidine both elicited rotational behavior in rats with unilateral lesion of the substantia nigra. The rotational behavior induced by either (+)-SKF 10,047 or phencyclidine was dose-dependently antagonized by DuP 734 with oral ED50 of 8.7 and 19.6 mumol/kg, respectively. The 5-HT2 receptor antagonist ICI 169,369, even at high doses (up to 33 mumol/kg, s.c.), did not antagonize the rotational behavior induced by (+)-SKF 10,047.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. N-acetylglucosaminyltransferase V modulates radiosensitivity and migration of small cell lung cancer through epithelial-mesenchymal transition.

    PubMed

    Huang, Chunyue; Huang, Miaojuan; Chen, Wenxia; Zhu, Weiliang; Meng, Hui; Guo, Linlang; Wei, Ting; Zhang, Jian

    2015-11-01

    N-acetylglucosaminyltransferase V (Gnt-V) has been linked to the migration of various human cancers. Recently we have found that inhibition of Gnt-V increases the radiosensitivity of cancer cells. However, the mechanisms by which Gnt-V mediates radiosensitivity and migration, especially in small cell lung cancer (SCLC) remain unknown. In our study, two SCLC cell lines (H1688 and H146) were used to investigate whether Gnt-V modulated the radiosensitivity and migration of SCLC cells through the epithelial-mesenchymal transition (EMT). The results showed that the expression of Gnt-V correlated with the N stage in patients with SCLC. Overexpression of Gnt-V led to a further increase in the relative viable cell number and survival fraction with a decrease in apoptosis rate and Bax/Bcl-2 ratio, when the cells were treated with irradiation. By contrast, knockdown of Gnt-V with irradiation resulted in a further decrease in the relative viable cell number and survival fraction but an increase in apoptosis rate and Bax/Bcl-2 ratio. Cells expressing high levels of Gnt-V increased migration whereas low levels of Gnt-V suppressed cell migration. Besides, the transient knockdown of ZEB2 led to an increase in radiosensitivity and an inhibition in the migration of SCLC cells. Furthermore, Gnt-V was negatively correlated with E-cadherin expression but positively correlated with N-cadherin, vimentin and ZEB2 expression. Finally, an in vivo study revealed that upregulation of Gnt-V caused tumour growth more quickly, as well as the expression of EMT-related markers (N-cadherin, vimentin and ZEB2). Taken together, the study suggested that an elevation of Gnt-V could lead to the radiosensitivity and migration of SCLC cells by inducing EMT, thereby highlighting Gnt-V as a potential therapeutic target for the prevention of EMT-associated tumour radioresistance and migration.

  3. MiR-211/STAT5A Signaling Modulates Migration of Mesenchymal Stem Cells to Improve its Therapeutic Efficacy.

    PubMed

    Hu, Xinyang; Chen, Panpan; Wu, Yan; Wang, Kan; Xu, Yinchuan; Chen, Han; Zhang, Ling; Wu, Rongrong; Webster, Keith A; Yu, Hong; Zhu, Wei; Wang, Jian'an

    2016-07-01

    Our previous study showed that the therapeutic effects of mesenchymal stem cells (MSCs) transplantation were improved by enhancing migration. MicroRNA-211 (miR-211) can modulate the migratory properties of some cell types by mechanisms that are not fully understood. This study was designed to investigate a possible role for miR-211 in MSC migration, and whether genetic manipulation of miR-211 in MSCs could be used to enhance its beneficial effects of cell transplantation. Transwell assays confirmed that MSCs migration of was significantly impaired by miR-211 knockdown but enhanced by miR-211 overexpression. MiR-211 overexpressing MSCs also exhibited significantly increased cell engraftment in the peri-infarct areas of female rat hearts 2 days after intravenous transplantation of male MSCs as shown by GFP tracking and SYR gene quantification. This conferred a significant decrease in infarct size and improved cardiac performance. By using a loss or gain of gene function approach, we demonstrated that miR-211 targeted STAT5A to modulate MSCs migration, possibly by interacting with MAPK signaling. Furthermore, the beneficial effects of miR-211 overexpression in MSCs were abolished by simultaneous overexpression of STAT5A whereas the negative effects of miR-211 silencing on MSC migration were rescued by simultaneous downregulation of STAT5A. Finally, using ChIP-PCR and luciferase assays, we provide novel evidence that STAT3 can directly bind to promoter elements that activate miR-211 expression. STAT3/miR-211/STAT5A signaling plays a key role in MSCs migration. Intravenous infusion of genetically modified miR-211 overexpressing MSCs conveys enhanced protection from adverse post-MI remodeling compared with unmodified MSCs. Stem Cells 2016;34:1846-1858.

  4. A space oddity: geographic and specific modulation of migration in Eudyptes penguins.

    PubMed

    Thiebot, Jean-Baptiste; Cherel, Yves; Crawford, Robert J M; Makhado, Azwianewi B; Trathan, Philip N; Pinaud, David; Bost, Charles-André

    2013-01-01

    Post-breeding migration in land-based marine animals is thought to offset seasonal deterioration in foraging or other important environmental conditions at the breeding site. However the inter-breeding distribution of such animals may reflect not only their optimal habitat, but more subtle influences on an individual's migration path, including such factors as the intrinsic influence of each locality's paleoenvironment, thereby influencing animals' wintering distribution. In this study we investigated the influence of the regional marine environment on the migration patterns of a poorly known, but important seabird group. We studied the inter-breeding migration patterns in three species of Eudyptes penguins (E. chrysolophus, E. filholi and E. moseleyi), the main marine prey consumers amongst the World's seabirds. Using ultra-miniaturized logging devices (light-based geolocators) and satellite tags, we tracked 87 migrating individuals originating from 4 sites in the southern Indian Ocean (Marion, Crozet, Kerguelen and Amsterdam Islands) and modelled their wintering habitat using the MADIFA niche modelling technique. For each site, sympatric species followed a similar compass bearing during migration with consistent species-specific latitudinal shifts. Within each species, individuals breeding on different islands showed contrasting migration patterns but similar winter habitat preferences driven by sea-surface temperatures. Our results show that inter-breeding migration patterns in sibling penguin species depend primarily on the site of origin and secondly on the species. Such site-specific migration bearings, together with similar wintering habitat used by parapatrics, support the hypothesis that migration behaviour is affected by the intrinsic characteristics of each site. The paleo-oceanographic conditions (primarily, sea-surface temperatures) when the populations first colonized each of these sites may have been an important determinant of subsequent migration

  5. A Space Oddity: Geographic and Specific Modulation of Migration in Eudyptes Penguins

    PubMed Central

    Thiebot, Jean-Baptiste; Cherel, Yves; Crawford, Robert J. M.; Makhado, Azwianewi B.; Trathan, Philip N.; Pinaud, David; Bost, Charles-André

    2013-01-01

    Post-breeding migration in land-based marine animals is thought to offset seasonal deterioration in foraging or other important environmental conditions at the breeding site. However the inter-breeding distribution of such animals may reflect not only their optimal habitat, but more subtle influences on an individual’s migration path, including such factors as the intrinsic influence of each locality’s paleoenvironment, thereby influencing animals’ wintering distribution. In this study we investigated the influence of the regional marine environment on the migration patterns of a poorly known, but important seabird group. We studied the inter-breeding migration patterns in three species of Eudyptes penguins (E. chrysolophus, E. filholi and E. moseleyi), the main marine prey consumers amongst the World’s seabirds. Using ultra-miniaturized logging devices (light-based geolocators) and satellite tags, we tracked 87 migrating individuals originating from 4 sites in the southern Indian Ocean (Marion, Crozet, Kerguelen and Amsterdam Islands) and modelled their wintering habitat using the MADIFA niche modelling technique. For each site, sympatric species followed a similar compass bearing during migration with consistent species-specific latitudinal shifts. Within each species, individuals breeding on different islands showed contrasting migration patterns but similar winter habitat preferences driven by sea-surface temperatures. Our results show that inter-breeding migration patterns in sibling penguin species depend primarily on the site of origin and secondly on the species. Such site-specific migration bearings, together with similar wintering habitat used by parapatrics, support the hypothesis that migration behaviour is affected by the intrinsic characteristics of each site. The paleo-oceanographic conditions (primarily, sea-surface temperatures) when the populations first colonized each of these sites may have been an important determinant of subsequent

  6. Cellular adhesome screen identifies critical modulators of focal adhesion dynamics, cellular traction forces and cell migration behaviour.

    PubMed

    Fokkelman, Michiel; Balcıoğlu, Hayri E; Klip, Janna E; Yan, Kuan; Verbeek, Fons J; Danen, Erik H J; van de Water, Bob

    2016-08-17

    Cancer cells migrate from the primary tumour into surrounding tissue in order to form metastasis. Cell migration is a highly complex process, which requires continuous remodelling and re-organization of the cytoskeleton and cell-matrix adhesions. Here, we aimed to identify genes controlling aspects of tumour cell migration, including the dynamic organization of cell-matrix adhesions and cellular traction forces. In a siRNA screen targeting most cell adhesion-related genes we identified 200+ genes that regulate size and/or dynamics of cell-matrix adhesions in MCF7 breast cancer cells. In a subsequent secondary screen, the 64 most effective genes were evaluated for growth factor-induced cell migration and validated by tertiary RNAi pool deconvolution experiments. Four validated hits showed significantly enlarged adhesions accompanied by reduced cell migration upon siRNA-mediated knockdown. Furthermore, loss of PPP1R12B, HIPK3 or RAC2 caused cells to exert higher traction forces, as determined by traction force microscopy with elastomeric micropillar post arrays, and led to considerably reduced force turnover. Altogether, we identified genes that co-regulate cell-matrix adhesion dynamics and traction force turnover, thereby modulating overall motility behaviour.

  7. Cellular adhesome screen identifies critical modulators of focal adhesion dynamics, cellular traction forces and cell migration behaviour

    PubMed Central

    Fokkelman, Michiel; Balcıoğlu, Hayri E.; Klip, Janna E.; Yan, Kuan; Verbeek, Fons J.; Danen, Erik H. J.; van de Water, Bob

    2016-01-01

    Cancer cells migrate from the primary tumour into surrounding tissue in order to form metastasis. Cell migration is a highly complex process, which requires continuous remodelling and re-organization of the cytoskeleton and cell-matrix adhesions. Here, we aimed to identify genes controlling aspects of tumour cell migration, including the dynamic organization of cell-matrix adhesions and cellular traction forces. In a siRNA screen targeting most cell adhesion-related genes we identified 200+ genes that regulate size and/or dynamics of cell-matrix adhesions in MCF7 breast cancer cells. In a subsequent secondary screen, the 64 most effective genes were evaluated for growth factor-induced cell migration and validated by tertiary RNAi pool deconvolution experiments. Four validated hits showed significantly enlarged adhesions accompanied by reduced cell migration upon siRNA-mediated knockdown. Furthermore, loss of PPP1R12B, HIPK3 or RAC2 caused cells to exert higher traction forces, as determined by traction force microscopy with elastomeric micropillar post arrays, and led to considerably reduced force turnover. Altogether, we identified genes that co-regulate cell-matrix adhesion dynamics and traction force turnover, thereby modulating overall motility behaviour. PMID:27531518

  8. Poliovirus Receptor-Related 2: A Cholesterol-Responsive Gene Affecting Atherosclerosis Development by Modulating Leukocyte Migration.

    PubMed

    Rossignoli, Aránzazu; Shang, Ming-Mei; Gladh, Hanna; Moessinger, Christine; Foroughi Asl, Hassan; Talukdar, Husain Ahammad; Franzén, Oscar; Mueller, Steffen; Björkegren, Johan L M; Folestad, Erika; Skogsberg, Josefin

    2017-03-01

    Recently, poliovirus receptor-related 2 (Pvrl2) emerged as a top gene in a global gene expression study aiming to detect plasma cholesterol-responsive genes causally related to atherosclerosis regression in hypercholesterolemic mice. PVRL2 is an adherens junction protein implied to play a role in transendothelial migration of leukocytes, a key feature in atherosclerosis development. In this study, we investigated the effect of Pvrl2 deficiency on atherosclerosis development and transendothelial migration of leukocytes activity. APPROACH AND RESULTS: Pvrl2-deficient mice bred onto an atherosclerosis-prone background (Pvrl2(-/-)Ldlr(-/-)Apob(100/100)) had less atherosclerotic lesions and more stable plaques compared with littermate controls (Pvrl2(+/+)Ldlr(-/-)Apob(100/100)). Pvrl2(-/-)Ldlr(-/-)Apob(100/100) mice also showed a 49% decrease in transendothelial migration of leukocytes activity observed using the in vivo air pouch model. In accordance, augmented arterial wall expression of Pvrl2 during atherosclerosis progression coincided with an increased gene expression of migrating leukocytes into the vessel wall. Both in human and mice, gene and protein expression of PVRL2 was predominantly observed in the vascular endothelium according to the immunohistochemical and gene expression data. In addition, the cholesterol responsiveness of PVRL2 was also observed in humans. PVRL2 is a plasma cholesterol-responsive gene acting at endothelial sites of vascular inflammation that could potentially be a new therapeutic target for atherosclerosis prevention through its suggested transendothelial migration of leukocytes modulating activity. © 2017 American Heart Association, Inc.

  9. Focal adhesion kinase modulates radial glia-dependent neuronal migration through connexin-26.

    PubMed

    Valiente, Manuel; Ciceri, Gabriele; Rico, Beatriz; Marín, Oscar

    2011-08-10

    Focal adhesion kinase (FAK) is an intracellular kinase and scaffold protein that regulates migration in many different cellular contexts but whose function in neuronal migration remains controversial. Here, we have analyzed the function of FAK in two populations of neurons with very distinct migratory behaviors: cortical interneurons, which migrate tangentially and independently of radial glia; and pyramidal cells, which undergo glial-dependent migration. We found that FAK is dispensable for glial-independent migration but is cell-autonomously required for the normal interaction of pyramidal cells with radial glial fibers. Loss of FAK function disrupts the normal morphology of migrating pyramidal cells, delays migration, and increases the tangential dispersion of neurons arising from the same radial unit. FAK mediates this process by regulating the assembly of Connexin-26 contact points in the membrane of migrating pyramidal cells. These results indicate that FAK plays a fundamental role in the dynamic regulation of Gap-mediated adhesions during glial-guided neuronal migration in the mouse.

  10. Ascorbic acid modulates cell migration in differentiated HL-60 cells and peripheral blood leukocytes.

    PubMed

    Schwager, Joseph; Bompard, Albine; Weber, Peter; Raederstorff, Daniel

    2015-08-01

    The impact of L-ascorbic acid (L-AA) on the chemokinesis (CK) and chemotaxis (CT) of HL-60 cells and polymorphonuclear cells (PMN) was investigated. HL-60 cells were differentiated with DMSO, retinoic acid (RA), vitamin D, or L-AA. Chemokinesis and chemotaxis of differentiated HL-cells were assayed. Vitamin D3-treated HL-60 cells (dHL-60vitD3 cells) and RA-treated cells (dHL-60RA cells) acquired monocyte/macrophage-like and neutrophil-like phenotypes, respectively. DMSO induced the differentiation of an intermediate phenotype (dHL-60DMSO cells), whereas L-AA downregulated neutrophil markers (dHL-60L-AA cells). dHL-60DMSO cells had increased CK and potent CT in gradients of IL-8 and N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP). dHL-60RA cells and dHL-60L-AA cells migrated less toward IL-8 and fMLP; dHL-60vitD3 cells preferably responded to fMLP. L-AA enhanced CK of dHL-60DMSO cells and was a weak chemo-attractant. In human leukocytes, IL-8 and fMLP triggered receptor-mediated chemotaxis. CXCR2 and fMLPR were downregulated by IL-8 and fMLP, respectively. L-AA stimulated chemotaxis although significantly less than IL-8 and fMLP. IL-8 targeted chemotaxis was enhanced both in HL-60 cells and leukocytes when cells were incubated with L-AA. L-AA modulated chemokinesis and had significant chemo-attractant properties, which were independent on fMLP or IL-8 receptors. The results suggest that L-AA improves leukocyte function in innate immune responses. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. SIRT-1 regulates TGF-β-induced dermal fibroblast migration via modulation of Cyr61 expression.

    PubMed

    Kwon, Eun-Jeong; Park, Eun-Jung; Yu, Hyeran; Huh, Jung-Sik; Kim, Jinseok; Cho, Moonjae

    2017-07-27

    SIRT1 is a NAD-dependent protein deacetylase that participates in cellular regulation. The increased migration of fibroblasts is an important phenotype in fibroblast activation. The role of SIRT1 in cell migration remains controversial as to whether SIRT1 acts as an activator or suppressor of cell migration. Therefore, we have established the role of SIRT1 in the migration of human dermal fibroblasts and explored targets of SIRT1 during dermal fibroblast migration. SIRT1 and Cyr61 were expressed in human dermal fibroblasts and the stimulation with TGF-β further induced their expression. Treatment with resveratrol (RSV), a SIRT1 agonist, or overexpression of SIRT1 also promoted the expression Cyr61 in human dermal fibroblasts, whereas the inhibition of SIRT1 activity by nicotinamide or knockdown of SIRT1 decreased the level of Cyr61, as well as TGF-β or RSV-induced Cyr61 expression. Blocking of ERK signaling by PD98509 reduced the expression of Cyr61 induced by TGF-β or RSV. TGF-β, RSV, or SIRT1 overexpression enhanced β-catenin as well as Cyr61 expression. This stimulation was reduced by the Wnt inhibitor XAV939. RSV increased migration and nicotinamide attenuated RSV-induced migration of human dermal fibroblasts. Furthermore, SIRT1 overexpression promoted cell migration, whereas blocking Cyr61 attenuated SIRT1-stimulated migration of human dermal fibroblasts. SIRT1 increased cell migration by stimulating Cyr61 expression and the ERK and Wnt/β-catenin signaling. SIRT1-induced Cyr61 activity is very important for human dermal fibroblasts migration.

  12. Pertussis toxin-sensitive guanine nucleotide-binding protein(S) couple adenosine A1 and 5-hydroxytryptamine1A receptors to the same effector systems in rat hippocampus: biochemical and electrophysiological studies.

    PubMed

    Zgombick, J M; Beck, S G; Mahle, C D; Craddock-Royal, B; Maayani, S

    1989-04-01

    Distinct membrane receptors that elicit similar cellular responses may share elements of signal transduction. In the present study, rat hippocampal adenosine (AD) and 5-hydroxytryptamine (5-HT) receptors were chosen to test this possibility using biochemical and electrophysiological techniques. Responses elicited by the AD receptor that mediates the inhibition of forskolin-stimulated adenylyl cyclase activity in rat hippocampal membranes and hyperpolarization of resting membrane potential (RMP) in rat hippocampal pyramidal cells were characterized and compared, in the same preparation, with those analogous responses elicited by the 5-HT1A receptor. A series of AD agonists including the selective AD A1 agonist (R)-phenylisopropyladenosine [(R)-PIA] inhibited forskolin-stimulated adenylyl cyclase activity in rat hippocampal membranes in a concentration-dependent manner. Cyclopentyltheophylline (CPT), a selective AD A1 antagonist, was a potent, competitive antagonist of this response with a dissociation constant (Kb) of 6 nM (Schild analysis). The rank order of agonist EC50 values and antagonist Kb values, as well as stereoselectivity, are consistent with the classification of this receptor as the AD A1 receptor. Spiperone, a potent 5-HT1A antagonist, competitively antagonized 5-HT-mediated inhibition of forskolin-stimulated adenylyl cyclase activity in rat hippocampal membranes with a Kb value of 14 nM. Intracellular recording techniques revealed that AD, (R)-PIA, 5-HT, and 5-carboxyamidotryptamine (5-CT) elicited concentration-dependent hyperpolarization of RMP within the same hippocampal pyramidal cell. The maximal hyperpolarization obtained for the AD or 5-HT analogs was the same for individual pyramidal cells. CPT and spiperone antagonized the hyperpolarization by (R)-PIA and 5-CT, respectively. Saturating concentrations of spiperone failed to antagonize (R)-PIA-mediated responses and CPT did not block responses elicited by 5-HT in either the biochemical or

  13. Actin-binding protein G (AbpG) participates in modulating the actin cytoskeleton and cell migration in Dictyostelium discoideum

    PubMed Central

    Lin, Wei-Chi; Wang, Liang-Chen; Pang, Te-Ling; Chen, Mei-Yu

    2015-01-01

    Cell migration is involved in various physiological and pathogenic events, and the complex underlying molecular mechanisms have not been fully elucidated. The simple eukaryote Dictyostelium discoideum displays chemotactic locomotion in stages of its life cycle. By characterizing a Dictyostelium mutant defective in chemotactic responses, we identified a novel actin-binding protein serving to modulate cell migration and named it actin-binding protein G (AbpG); this 971–amino acid (aa) protein contains an N-terminal type 2 calponin homology (CH2) domain followed by two large coiled-coil regions. In chemoattractant gradients, abpG− cells display normal directional persistence but migrate significantly more slowly than wild-type cells; expressing Flag-AbpG in mutant cells eliminates the motility defect. AbpG is enriched in cortical/lamellipodial regions and colocalizes well with F-actin; aa 401–600 and aa 501–550 fragments of AbpG show the same distribution as full-length AbpG. The aa 501–550 region of AbpG, which is essential for AbpG to localize to lamellipodia and to rescue the phenotype of abpG− cells, is sufficient for binding to F-actin and represents a novel actin-binding protein domain. Compared with wild-type cells, abpG− cells have significantly higher F-actin levels. Collectively our results suggest that AbpG may participate in modulating actin dynamics to optimize cell locomotion. PMID:25609090

  14. Macrophage migration inhibitory factor homolog from Plasmodium yoelii modulates monocyte recruitment and activation in spleen during infection

    PubMed Central

    Zhang, Yanhui; Miura, Kazutoyo; Li, Jian; Tullo, Gregory; Zhu, Feng; Hong, Lingxian; Lin, Tianlong; Su, Xin-zhuan; Long, Carole

    2012-01-01

    Macrophage migration inhibitory factor (MIF) has been shown to be involved in the pathogenesis of severe malaria. Malaria parasites express an MIF homolog that may play a role in regulating host immune responses and a recent study showed that overexpression of MIF reduced parasitemia in a mouse malaria model. Another recent study showed migration of monocytes to the spleen contributed to the control of blood stage infection. However, there are few papers describing the effect of MIF on monocyte recruitment/activation during the infection. We generated recombinant P. yoelii MIF (rPyMIF) and investigated its function on purified mouse CD11b+ cells in vitro and monocyte responses in vivo. The result shows that rPyMIF protein bound to mouse CD11b+ cells and inhibited their random migration in vitro. On the other hand, rPyMIF did not induce cytokine release from the cells directly or modulate LPS-induced cytokine release. Mice immunized with rPyMIF showed transient, but significantly lower parasitemia than the control mice at day 3 after lethal Py17XL challenge. The total number of CD11b+ cells in the spleens was significantly higher in rPyMIF-immunized group. Further investigation revealed that there were significantly higher numbers of recruited and activated monocytes in the spleens of rPyMIF immunization group on day 3. These results indicate that PyMIF potentially modulates monocyte recruitment and activation during infection of P. yoelii erythrocytic stages. PMID:22015474

  15. Nitric Oxide Modulates Postnatal Bone Marrow-Derived Mesenchymal Stem Cell Migration

    PubMed Central

    Fuseler, John W.; Valarmathi, Mani T.

    2016-01-01

    Nitric oxide (NO) is a small free-radical gas molecule, which is highly diffusible and can activate a wide range of downstream effectors, with rapid and widespread cellular effects. NO is a versatile signaling mediator with a plethora of cellular functions. For example, NO has been shown to regulate actin, the microfilament, dependent cellular functions, and also acts as a putative stem cell differentiation-inducing agent. In this study, using a wound-healing model of cellular migration, we have explored the effect of exogenous NO on the kinetics of movement and morphological changes in postnatal bone marrow-derived mesenchymal stem cells (MSCs). Cellular migration kinetics and morphological changes of the migrating MSCs were measured in the presence of an NO donor (S-Nitroso-N-Acetyl-D,L-Penicillamine, SNAP), especially, to track the dynamics of single-cell responses. Two experimental conditions were assessed, in which SNAP (200 μM) was applied to the MSCs. In the first experimental group (SN-1), SNAP was applied immediately following wound formation, and migration kinetics were determined for 24 h. In the second experimental group (SN-2), MSCs were pretreated for 7 days with SNAP prior to wound formation and the determination of migration kinetics. The generated displacement curves were further analyzed by non-linear regression analysis. The migration displacement of the controls and NO treated MSCs (SN-1 and SN-2) was best described by a two parameter exponential functions expressing difference constant coefficients. Additionally, changes in the fractal dimension (D) of migrating MSCs were correlated with their displacement kinetics for all the three groups. Overall, these data suggest that NO may evidently function as a stop migration signal by disordering the cytoskeletal elements required for cell movement and proliferation of MSCs. PMID:27933292

  16. Colonic Migrating Motor Complexes, High Amplitude Propagating Contractions, Neural Reflexes and the Importance of Neuronal and Mucosal Serotonin

    PubMed Central

    Smith, Terence K; Park, Kyu Joo; Hennig, Grant W

    2014-01-01

    The colonic migrating motor complex (CMMC) is a critical neurally mediated rhythmic propulsive contraction observed in the large intestine of many mammals. It seems to be equivalent to the high amplitude propagating contractions (HAPCs) in humans. This review focuses on the probable neural mechanisms involved in producing the CMMC or HAPC, their likely dependence on mucosal and neuronal serotonin and pacemaker insterstitial cells of Cajal networks and how intrinsic neural reflexes affect them. Discussed is the possibility that myenteric 5-hydroxytryptamine (5-HT) neurons are not only involved in tonic inhibition of the colon, but are also involved in generating the CMMC and modulation of the entire enteric nervous system, including coupling motility to secretion and blood flow. Mucosal 5-HT appears to be important for the initiation and effective propagation of CMMCs, although this mechanism is a longstanding controversy since the 1950s, which we will address. We argue that the slow apparent propagation of the CMMC/HAPC down the colon is unlikely to result from a slowly conducting wave front of neural activity, but more likely because of an interaction between ascending excitatory and descending (serotonergic) inhibitory neural pathways interacting both within the myenteric plexus and at the level of the muscle. That is, CMMC/HAPC propagation appears to be similar to esophageal peristalsis. The suppression of inhibitory (neuronal nitric oxide synthase) motor neurons and mucosal 5-HT release by an upregulation of prostaglandins has important implications in a number of gastrointestinal disorders, especially slow transit constipation. PMID:25273115

  17. FOXA1 modulates EAF2 regulation of AR transcriptional activity, cell proliferation, and migration in prostate cancer cells.

    PubMed

    Guo, Wenhuan; Keener, Anne L; Jing, Yifeng; Cai, Liquan; Ai, Junkui; Zhang, Jian; Fisher, A L; Fu, Guohui; Wang, Zhou

    2015-06-15

    ELL-associated factor 2 (EAF2) is an androgen-regulated tumor suppressor in the prostate. However, the mechanisms underlying tumor suppressive function of EAF2 are still largely unknown. Identification of factors capable of modulating EAF2 function will help elucidate the mechanisms underlying EAF2 tumor suppressive function. Using eaf-1(the ortholog of EAF2) mutant C. elegans model, RNAi screen was used to identify factors on the basis of their knockdown to synergistically enhance the reduced fertility phenotype of the eaf-1 mutant C. elegans. In human cells, the interaction of EAF2 with FOXA1 and the effect of EAF2 on the FOXA1 protein levels were determined by co-immunoprecipitation and protein stability assay. The effect of EAF2 and/or FOXA1 knockdown on the expression of AR-target genes was determined by real-time RT-PCR and luciferase reporter assays. The effect of EAF2 and/or FOXA1 knockdown on LNCaP human prostate cancer cell proliferation and migration was tested using BrdU assay and transwell migration assay. RNAi screen identified pha-4, the C. elegans ortholog of mammalian FOXA1, on the basis of its knockdown to synergistically enhance the reduced fertility phenotype of the eaf-1 mutant C. elegans causing sterility. EAF2 co-immunoprecipitated with FOXA1. EAF2 knockdown enhanced endogenous FOXA1 protein level, whereas transfected GFP-EAF2 down-regulated the FOXA1 protein. Also, EAF2 knockdown enhanced the expression of AR-target genes, cell proliferation, and migration in LNCaP cells. However, FOXA1 knockdown inhibited the effect of EAF2 knockdown on AR-target gene expression, cell proliferation, and migration in LNCaP cells, suggesting that FOXA1 can modulate EAF2 regulation of AR transcriptional activation, cell proliferation, and migration. These findings suggest that regulation of the AR signaling pathway, cell proliferation, and migration through FOXA1 represents an important mechanism of EAF2 suppression of prostate carcinogenesis. © 2015 Wiley

  18. Amniotic membrane stimulates cell migration by modulating Transforming Growth Factor-β signaling.

    PubMed

    Ruiz-Cañada, Catalina; Bernabé-García, Ángel; Liarte, Sergio; Insausti, Carmen Luisa; Angosto, Diego; Moraleda, José María; Castellanos, Gregorio; Nicolás, Francisco José

    2017-06-16

    Keratinocyte migration is a mandatory aspect of wound-healing. We have previously shown that Amniotic Membrane (AM) applied to chronic wounds assists healing through a process resulting in overexpression of c-Jun at the wound's leading edge. Also, we have demonstrated that amniotic membrane modifies the genetic program induced by TGF-ß in chronic wounds. In this paper, we used a scratch assay of Mv1Lu and HaCaT cells to examine the influence of AM application on the underlying signaling during scratch closure. AM-application induced c-Jun phosphorylation at the leading-edge of scratch wounds in a process dependent on MAPK and JNK signaling. Strikingly, when the TGF-ß-dependent Smad-activation inhibitor SB431542 was used together with AM, migration improvement was partially restrained, while addition of TGF-ß had a synergistic effect on the AM induced cell migration. Moreover, antagonizing TGF-ß with specific antibodies in both cell lines or knocking out TGF-ß receptors in Mv1Lu cells had similar effects on cell migration than using SB431542. Furthermore, we found that AM was able to attenuate TGF-ß-Smad signaling specifically at the migrating edge; AM treatment abated Smad2 and Smad3 nuclear localization in response to TGF-ß in a process dependent on MEK-1 activation but independent on EGF-Receptor or JNK activation. The involvement of Smad signaling onto AM effects on HaCaT keratinocytes was further corroborated by overexpression of either Smad2 or Smad3 and the use of Smad-phosphorylation specific inhibitors, revealing a differential influence on AM induced migration for each Smad. Thus, AM TGF-ß-Smad-signaling abating is essential for optimal cell migration and wound closure. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  19. Endotoxin activation of endothelium for polymorphonuclear leucocyte transendothelial migration and modulation by interferon-gamma.

    PubMed Central

    Issekutz, A C; Lopes, N

    1993-01-01

    Endotoxin [lipopolysaccharide (LPS)] is a potent inflammatory stimulus and can activate human umbilical vein endothelium (HUVE) for leucocyte adhesiveness and transendothelial migration. Here we investigated the role of HUVE-secreted cytokines in this process. When HUVE monolayers were grown on filters and preincubated for 3 hr with LPS, 51Cr-labelled polymorphonuclear leucocytes (PMNL) migrated across the HUVE in a dose- and time-dependent manner. Maximal PMNL transmigration with LPS (1 ng/ml) was 26 +/- 3% of added PMNL in 75 min. Neutralizing antibodies to interleukin-1 alpha (IL-1 alpha) and IL-1 beta, tumour necrosis factor-alpha (TNF-alpha), IL-8 or recombinant IL-1 receptor antagonist had no effect on the activation by LPS of the HUVE for supporting migration of PMNL. The HUVE 'activated state' declined with prolonged (22 hr) exposure to LPS, as reflected by a decrease in PMNL transendothelial migration to 5.5 +/- 1% and in the expression of the endothelial cell adhesion molecule, E-selectin, as compared to stimulation with LPS for 3 hr. However, simultaneous exposure to interferon-gamma (IFN-gamma) (200 IU/ml) and LPS maintained maximal PMNL transendothelial migration (28 +/- 4%) for at least 24 hr, prolonged E-selectin expression by HUVE and superinduced intracellular adhesion molecule-1 (ICAM-1) expression. The PMNL transendothelial migration was blocked by > 90% by monoclonal antibody (mAb) to CD18 with either 3 hr of LPS or 22 hr LPS + IFN-gamma stimulation. Migration was partially inhibited by mAb to E-selectin (30-40%) or to ICAM-1 (35-45%) and by a combination of both reagents (50-60%) under both stimulation conditions. Thus, LPS activation of HUVE for PMNL transendothelial migration: (a) does not require secretion of IL-1, TNF-alpha or IL-8 by the endothelium, (b) IFN-gamma enhances and prolongs endothelial activation by LPS and may increase leucocyte infiltration in LPS or bacterial inflammatory reactions, and (c) CD18-dependent mechanisms are

  20. THE TMEFF2 TUMOR SUPPRESSOR MODULATES INTEGRIN EXPRESSION, RHOA ACTIVATION AND MIGRATION OF PROSTATE CANCER CELLS

    PubMed Central

    Chen, Xiaofei; Corbin, Joshua M.; Tipton, Greg J.; Yang, Li V.; Asch, Adam S.; Ruiz-Echevarría, Maria J.

    2014-01-01

    Cell adhesion and migration play important roles in physiological and pathological states, including embryonic development and cancer invasion and metastasis. The type I transmembrane protein with epidermal growth factor and two follistatin motifs 2 (TMEFF2) is expressed mainly in brain and prostate and its expression is deregulated in prostate cancer. We have previously shown that TMEFF2 can function as a tumor suppressor by inhibiting cell migration and invasion of prostate cells. However, the molecular mechanisms involved in this inhibition are not clear. In this study we demonstrate that TMEFF2 affects cell adhesion and migration of prostate cancer cells and that this effect correlates with changes in integrin expression and RhoA activation. Deletion of a 13 basic-rich amino acid region in the cytoplasmic domain of TMEFF2 prevented these effects. Overexpression of TMEFF2 reduced cell attachment and migration on vitronectin and caused a concomitant decrease in RhoA activation, stress fiber formation and expression of αv, β1 and β3 integrin subunits. Conversely, TMEFF2 interference in 22Rv1 prostate cancer cells resulted in increased integrin expression. Results obtained with a double TRAMP/TMEFF2 transgenic mouse also indicated that TMEFF2 expression reduced integrin expression in the mouse prostate. In summary, the data presented here indicate an important role of TMEFF2 in regulating cell adhesion and migration that involves integrin signaling and is mediated by its cytoplasmic domain. PMID:24632071

  1. N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-nitrophenyl) cyclohexanecarboxamide: a novel pre- and postsynaptic 5-hydroxytryptamine(1A) receptor antagonist active on the lower urinary tract.

    PubMed

    Leonardi, A; Guarneri, L; Poggesi, E; Angelico, P; Velasco, C; Cilia, A; Testa, R

    2001-12-01

    N-[2-[4-(2-Methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-nitrophenyl) cyclohexanecarboxamide (Rec 15/3079) was synthesized with the aim of obtaining a novel compound with 5-hydroxytryptamine (5-HT)(1A) antagonistic properties and activity in controlling bladder function at the level of the central nervous system. Rec 15/3079 showed a selective high affinity for the 5-HT(1A) receptor (K(i) = 0.2 nM). At the human recombinant 5-HT(1A) receptor, Rec 15/3079 acted as a competitive, neutral antagonist in that it did not modify basal [(35)S]guanosine-5'-O-(3-thio)triphosphate binding to HeLa cell membranes but shifted the activation isotherm to 5-HT to the right, in a parallel manner, with a pK(b) value of 10.5. Accordingly, Rec 15/3079 (i.v.) potently antagonized 8-hydroxy-2-dipropylaminotetralin (8-OH-DPAT)-induced hypothermia in mice (ID(50) = 20 microg/kg) and 8-OH-DPAT-induced forepaw treading in rats (ID(50) = 36 microg/kg). In vitro Rec 15/3079 was poorly active in antagonizing carbachol-induced bladder (pD'(2) = 5.03) and norepinephrine-induced urethral (apparent pK(b) = 6) contractions. However, in anesthetized rats, Rec 15/3079 (10-100 microg/kg i.v.) blocked isovolumic bladder contractions with no effect on their amplitude. In conscious rats and guinea pigs with bladders filled with saline, Rec 15/3079 (300-1000 microg/kg i.v.) increased bladder volume capacity (BVC) without affecting bladder contractility. In conscious rats with bladders filled with dilute acetic acid, Rec 15/3079 (300 microg/kg i.v.) reversed the decrease of BVC induced by the acid. To evaluate apparent selective effect on lower urinary tract reflexes, Rec 15/3079 was tested in experimental models for sedative, analgesic, anxiolytic, and antidepressant activity. Rec 15/3079 showed only a slight decrease in the duration of immobility in the behavioral despair test (antidepressant activity) at 1 mg/kg i.v. No anxiolytic activity was observed at 10 mg/kg i.v. No effect was observed in the hot plate

  2. Annexin A6 and Late Endosomal Cholesterol Modulate Integrin Recycling and Cell Migration.

    PubMed

    García-Melero, Ana; Reverter, Meritxell; Hoque, Monira; Meneses-Salas, Elsa; Koese, Meryem; Conway, James R W; Johnsen, Camilla H; Alvarez-Guaita, Anna; Morales-Paytuvi, Frederic; Elmaghrabi, Yasmin A; Pol, Albert; Tebar, Francesc; Murray, Rachael Z; Timpson, Paul; Enrich, Carlos; Grewal, Thomas; Rentero, Carles

    2016-01-15

    Annexins are a family of proteins that bind to phospholipids in a calcium-dependent manner. Earlier studies implicated annexin A6 (AnxA6) to inhibit secretion and participate in the organization of the extracellular matrix. We recently showed that elevated AnxA6 levels significantly reduced secretion of the extracellular matrix protein fibronectin (FN). Because FN is directly linked to the ability of cells to migrate, this prompted us to investigate the role of AnxA6 in cell migration. Up-regulation of AnxA6 in several cell models was associated with reduced cell migration in wound healing, individual cell tracking and three-dimensional migration/invasion assays. The reduced ability of AnxA6-expressing cells to migrate was associated with decreased cell surface expression of αVβ3 and α5β1 integrins, both FN receptors. Mechanistically, we found that elevated AnxA6 levels interfered with syntaxin-6 (Stx6)-dependent recycling of integrins to the cell surface. AnxA6 overexpression caused mislocalization and accumulation of Stx6 and integrins in recycling endosomes, whereas siRNA-mediated AnxA6 knockdown did not modify the trafficking of integrins. Given our recent findings that inhibition of cholesterol export from late endosomes (LEs) inhibits Stx6-dependent integrin recycling and that elevated AnxA6 levels cause LE cholesterol accumulation, we propose that AnxA6 and blockage of LE cholesterol transport are critical for endosomal function required for Stx6-mediated recycling of integrins in cell migration.

  3. Annexin A6 and Late Endosomal Cholesterol Modulate Integrin Recycling and Cell Migration*

    PubMed Central

    García-Melero, Ana; Reverter, Meritxell; Hoque, Monira; Meneses-Salas, Elsa; Koese, Meryem; Conway, James R. W.; Johnsen, Camilla H.; Alvarez-Guaita, Anna; Morales-Paytuvi, Frederic; Elmaghrabi, Yasmin A.; Pol, Albert; Tebar, Francesc; Murray, Rachael Z.; Timpson, Paul; Enrich, Carlos; Grewal, Thomas; Rentero, Carles

    2016-01-01

    Annexins are a family of proteins that bind to phospholipids in a calcium-dependent manner. Earlier studies implicated annexin A6 (AnxA6) to inhibit secretion and participate in the organization of the extracellular matrix. We recently showed that elevated AnxA6 levels significantly reduced secretion of the extracellular matrix protein fibronectin (FN). Because FN is directly linked to the ability of cells to migrate, this prompted us to investigate the role of AnxA6 in cell migration. Up-regulation of AnxA6 in several cell models was associated with reduced cell migration in wound healing, individual cell tracking and three-dimensional migration/invasion assays. The reduced ability of AnxA6-expressing cells to migrate was associated with decreased cell surface expression of αVβ3 and α5β1 integrins, both FN receptors. Mechanistically, we found that elevated AnxA6 levels interfered with syntaxin-6 (Stx6)-dependent recycling of integrins to the cell surface. AnxA6 overexpression caused mislocalization and accumulation of Stx6 and integrins in recycling endosomes, whereas siRNA-mediated AnxA6 knockdown did not modify the trafficking of integrins. Given our recent findings that inhibition of cholesterol export from late endosomes (LEs) inhibits Stx6-dependent integrin recycling and that elevated AnxA6 levels cause LE cholesterol accumulation, we propose that AnxA6 and blockage of LE cholesterol transport are critical for endosomal function required for Stx6-mediated recycling of integrins in cell migration. PMID:26578516

  4. Fucoidan modulates cytokine production and migration of THP‑1‑derived macrophages via colony‑stimulating factor‑1.

    PubMed

    Li, Peng; Wang, Huayang; Shao, Qianqian; Kong, Beihua; Qu, Xun

    2017-04-01

    Fucoidan is known for its various biological activities, including immunomodulatory effects on immune cells. However, the effect of fucoidan on the functions of macrophages remains to be elucidated. The present study examined the effects of fucoidan on cytokine production and migration of THP‑1‑derived macrophages and its potential mechanisms. Fucoidan was added during the differentiation process of THP‑1‑derived macrophages along with lipopolysaccharide and interferon‑γ for 42 h, and then macrophages were harvested for functional assays. Fucoidan altered the morphology of THP‑1‑derived macrophages, and also attenuated their migration activity and pro‑inflammatory cytokine production. Additionally, THP‑1‑derived macrophages intensively produced colony‑stimulating factor‑1 (CSF‑1), which was significantly decreased by fucoidan. CSF‑1 neutralizing antibody attenuated the basic production level of pro‑inflammatory cytokines in macrophages. Furthermore, when recombinant human CSF‑1 was added along with fucoidan, the attenuating effects of fucoidan on migration and cytokine production were significantly reversed. In conclusion, the present study suggests that macrophages appear to be a potential target in the immunomodulatory action of fucoidan, and CSF‑1 may be involved in this modulation.

  5. bFGF induces changes in hyaluronan synthase and hyaluronidase isoform expression and modulates the migration capacity of fibrosarcoma cells.

    PubMed

    Berdiaki, Aikaterini; Nikitovic, Dragana; Tsatsakis, Aristeidis; Katonis, Pavlos; Karamanos, Nikos K; Tzanakakis, George N

    2009-10-01

    Hyaluronan (HA) a glycosaminoglycan, is capable of transmitting extracellular matrix derived signals to regulate cellular functions. In this study, we investigated whether the changes in HT1080 and B6FS fibrosarcoma cell lines HA metabolism induced by basic fibroblast growth factor (bFGF) are correlated to their migration. Real-time PCR, in vitro wound healing assay, siRNA transfection, enzyme digestions, western blotting and immunofluorescence were utilized. bFGF inhibited the degradation of HA by decreasing hyaluronidase-2 expression in HT1080 cells (p=0.0028), increased HA-synthase-1 and -2 expression as we previously found and enhanced high molecular weight HA deposition in the pericellular matrix. Increased endogenous HA production (p=0.0022) and treatment with exogenous high molecular weight HA (p=0.0268) correlated with a significant decrease of HT1080 cell migration capacity. Transfection with siHAS2 and siHAS1 showed that mainly HAS1 synthesized high molecular weight HA regulates HT1080 cell motility. Induced degradation of the HA content by hyaluronidase treatment and addition of low molecular weight HA, resulted in a significant stimulation of HT1080 cells' motility (p<0.01). In contrast, no effects on B6FS fibrosarcoma cell motility were observed. bFGF regulates, in a cell-specific manner the migration capability of fibrosarcoma cells by modulating their HA metabolism. HA metabolism is suggested to be a potential therapeutic target in fibrosarcoma.

  6. Phosphorylation of serine-504 of tNOX (ENOX2) modulates cell proliferation and migration in cancer cells

    SciTech Connect

    Zeng, Zih-Ming; Chuang, Show-Mei; Chang, Ting-Chia; Hong, Chen-Wei; Chou, Jou-Chun; Yang, Jaw-Ji; Chueh, Pin Ju

    2012-08-15

    Tumor-associated NADH oxidase (tNOX; ENOX2) is a growth-related protein expressed in transformed cells. Consistent with this function, tNOX knockdown by RNA interference leads to a significant reduction in cell proliferation and migration in HeLa cells, whereas tNOX overexpression confers an aggressive phenotype. Here, for the first time, we report that tNOX is phosphorylated by protein kinase C{delta} (PKC{delta}) both in vitro and in vivo. Replacement of serine-504 with alanine significantly reduces phosphorylation by PKC{delta}. Co-immunoprecipitation experiments reveal an interaction between tNOX and PKC{delta}. Moreover, whereas overexpression of wild-type tNOX in NIH3T3 cells increases cell proliferation and migration, overexpression of the S504A tNOX mutant leads to diminished cell proliferation and migration, reflecting reduced stability of the unphosphorylatable tNOX mutant protein. Collectively, these results suggest that phosphorylation of serine-504 by PKC{delta} modulates the biological function of tNOX.

  7. Low Doses of Curcuma longa Modulates Cell Migration and Cell-Cell Adhesion.

    PubMed

    de Campos, Paloma Santos; Matte, Bibiana Franzen; Diel, Leonardo Francisco; Jesus, Luciano Henrique; Bernardi, Lisiane; Alves, Alessandro Menna; Rados, Pantelis Varvaki; Lamers, Marcelo Lazzaron

    2017-09-01

    Cell invasion and metastasis are involved in clinical failures in cancer treatment, and both events require the acquisition of a migratory behavior by tumor cells. Curcumin is a promising natural product with anti-proliferative activity, but its effects on cell migration are still unclear. We evaluated the effects of curcumin on the proliferation, apoptosis, migration, and cell-cell adhesion of keratinocyte, oral squamous cell carcinoma (OSCC), and fibroblast cell lines, as well as in a xenograft model of OSCC. Curcumin (2 μM) decreased cell proliferation in cell lines with mesenchymal characteristics, while cell death was detected only at 50 μM. We observed that highly migratory cells showed a decrease on migration speed and directionality when treated with 2 or 5 μM of curcumin (50% and 40%, respectively, p < 0.05). Using spheroids, we observed that curcumin dose dependently decreased cell-cell adhesion, especially on tumor-derived spheroids. Also, in a xenograft model with patient-derived OSCC cells, the administration of curcumin decreased tumor growth and aggressiveness when compared with untreated tumors, indicating the potential antitumor effect in oral cancer. These results suggest that lower doses of curcumin can influence several steps involved in tumorigenesis, including migration properties, suggesting a possible use in cancer therapy. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  8. CalpB modulates border cell migration in Drosophila egg chambers

    PubMed Central

    2012-01-01

    Background Calpains are calcium regulated intracellular cysteine proteases implicated in a variety of physiological functions and pathological conditions. The Drosophila melanogaster genome contains only two genes, CalpA and CalpB coding for canonical, active calpain enzymes. The movement of the border cells in Drosophila egg chambers is a well characterized model of the eukaryotic cell migration. Using this genetically pliable model we can investigate the physiological role of calpains in cell motility. Results We demonstrate at the whole organism level that CalpB is implicated in cell migration, while the structurally related CalpA paralog can not fulfill the same function. The downregulation of the CalpB gene by mutations or RNA interference results in a delayed migration of the border cells in Drosophila egg chambers. This phenotype is significantly enhanced when the focal adhesion complex genes encoding for α-PS2 integrin ( if), β-PS integrin ( mys) and talin ( rhea) are silenced. The reduction of CalpB activity diminishes the release of integrins from the rear end of the border cells. The delayed migration and the reduced integrin release phenotypes can be suppressed by expressing wild-type talin-head in the border cells but not talin-headR367A, a mutant form which is not able to bind β-PS integrin. CalpB can cleave talin in vitro, and the two proteins coimmunoprecipitate from Drosophila extracts. Conclusions The physiological function of CalpB in border cell motility has been demonstrated in vivo. The genetic interaction between the CalpB and the if, mys, as well as rhea genes, the involvement of active talin head-domains in the process, and the fact that CalpB and talin interact with each other collectively suggest that the limited proteolytic cleavage of talin is one of the possible mechanisms through which CalpB regulates cell migration. PMID:22827336

  9. Pancortins interact with amyloid precursor protein and modulate cortical cell migration

    PubMed Central

    Rice, Heather C.; Townsend, Matthew; Bai, Jilin; Suth, Seiyam; Cavanaugh, William; Selkoe, Dennis J.; Young-Pearse, Tracy L.

    2012-01-01

    Neuronal precursor cell migration in the developing mammalian brain is a complex process requiring the coordinated interaction of numerous proteins. We have recently shown that amyloid precursor protein (APP) plays a role in migration into the cortical plate through its interaction with two cytosolic signaling proteins, disabled 1 (DAB1) and disrupted in schizophrenia 1 (DISC1). In order to identify extracellular factors that may signal through APP to regulate migration, we performed an unbiased mass spectrometry-based screen for factors that bind to the extracellular domain of APP in the rodent brain. Through this screen, we identified an interaction between APP and pancortins, proteins expressed throughout the developing and mature cerebral cortex. Via co-immunoprecipitation, we show that APP interacts with all four of the mammalian pancortin isoforms (AMY, AMZ, BMY, BMZ). We demonstrate that the BMZ and BMY isoforms of pancortin can specifically reduce β-secretase- but not α-secretase-mediated cleavage of endogenous APP in cell culture, suggesting a biochemical consequence of the association between pancortins and APP. Using in utero electroporation to overexpress and knock down specific pancortin isoforms, we reveal a novel role for pancortins in migration into the cortical plate. Interestingly, we observe opposing roles for alternate pancortin isoforms, with AMY overexpression and BMZ knock down both preventing proper migration of neuronal precursor cells. Finally, we show that BMZ can partially rescue a loss of APP expression and that APP can rescue effects of AMY overexpression, suggesting that pancortins act in conjunction with APP to regulate entry into the cortical plate. Taken together, these results suggest a biochemical and functional interaction between APP and pancortins, and reveal a previously unidentified role for pancortins in mammalian cortical development. PMID:22992957

  10. Integrin {alpha}6 cleavage: A novel modification to modulate cell migration

    SciTech Connect

    Pawar, Sangita C.; Demetriou, Manolis C.; Nagle, Raymond B.; Bowden, G. Tim; Cress, Anne E. . E-mail: acress@azcc.arizona.edu

    2007-04-01

    Integrins play a major role in cell adhesion and migration. Previous work reported that a cleaved form of integrin {alpha}6 ({alpha}6p) was detected in invasive human prostate cancer tissue, absent in normal prostate tissue and was produced by urokinase-type Plasminogen Activator (uPA) in a plasmin-independent manner. Using site-directed mutagenesis we identified amino acid residues R594 and R595, located in the 'stalk' region of integrin {alpha}6, as essential for cleavage. The cleavage site is located on the extracellular region of the protein between the {beta}-barrel domain and the thigh domain. Prostate cancer cells (PC3N) were stably transfected to overexpress the cleavable, wild-type (PC3N-{alpha}6-WT) or the non-cleavable form of integrin {alpha}6 (PC3N-{alpha}6-RR). The number of cells invading laminin 111- and laminin 332-coated filters by PC3N-{alpha}6-WT cells increased by threefold as compared to PC3N-{alpha}6-RR cells. Plasminogen activator inhibitor-1 (PAI-1) reduced the invasion of PC3N-{alpha}6-WT cells by approximately 42% through laminin 332-coated filters and plasmin inhibitor aprotinin had no significant effect. Linear cell migration increased production of integrin {alpha}6p in the PC3N-{alpha}6-WT cells and not in the PC3N-{alpha}6-RR cells and 32% of the PC3N-{alpha}6-WT cells migrated on laminin 111 in the linear migration assay as compared to the 5% PC3N-{alpha}6-RR cells. These data taken together suggest that the uPA-mediated cell surface cleavage of the {alpha}6 integrin extracellular domain is involved in tumor cell invasion and migration on laminin.

  11. Cigarette smoke modulates PC3 prostate cancer cell migration by altering adhesion molecules and the extracellular matrix

    PubMed Central

    YANG, SUPING; LONG, MINICA; TACHADO, SOUVENIR D.; SENG, SEYHA

    2015-01-01

    Prostate cancer (PCa) is the second leading cause of cancer-related mortality among American males. Studies suggest that cigarette smoking is associated with the progression of PCa; however, the molecular mechanisms underlying this process have not been extensively investigated. PCa progression is characterized by increased cell migration and alterations in extracellular matrix (ECM)- and cell adhesion molecule (CAM)-related gene expression. In the present study, the influence of cigarette smoke medium (SM) on cell migration and on the expression of ECM- and CAM-related genes in PC3 prostate adenocarcinoma cells was investigated. According to a wound-healing assay, SM treatment promoted PC3 cell migration. RNA expression levels from SM-treated and control cells were analyzed using a polymerase chain reaction (PCR) array. Of 84 genes analyzed, 27.38% (23/84) exhibited a ≥2-fold change in threshold cycle in PC3 cells following 0.5% SM treatment. Functional gene grouping analysis demonstrated that SM treatment modulated the RNA transcription of approximately 18.4% of CAMs and 33.93% of ECM-related genes. Quantitative PCR analysis showed that SM treatment led to a significant decrease in transcription levels of the following genes: Collagen 5 α-1(V), connective tissue growth factor, integrin β-2, kallmann syndrome 1, laminin α 3, matrix metallopeptidase 7 (MMP7), MMP13, secreted protein acidic cysteine-rich, thrombospondin-2 and versican; and that SM significantly increased the transcription levels of MMP2 and MMP12. Furthermore, MMP2 knockdown significantly reduced the migration of SM-treated PC3 cells. The present study provides novel insights into the association of cigarette smoking with PCa progression, via the alteration of ECM/CAM interactions. PMID:26351771

  12. Cigarette smoke modulates PC3 prostate cancer cell migration by altering adhesion molecules and the extracellular matrix.

    PubMed

    Yang, Suping; Long, Minica; Tachado, Souvenir D; Seng, Seyha

    2015-11-01

    Prostate cancer (PCa) is the second leading cause of cancer‑related mortality among American males. Studies suggest that cigarette smoking is associated with the progression of PCa; however, the molecular mechanisms underlying this process have not been extensively investigated. PCa progression is characterized by increased cell migration and alterations in extracellular matrix (ECM)‑ and cell adhesion molecule (CAM)‑related gene expression. In the present study, the influence of cigarette smoke medium (SM) on cell migration and on the expression of ECM‑ and CAM‑related genes in PC3 prostate adenocarcinoma cells was investigated. According to a wound‑healing assay, SM treatment promoted PC3 cell migration. RNA expression levels from SM‑treated and control cells were analyzed using a polymerase chain reaction (PCR) array. Of 84 genes analyzed, 27.38% (23/84) exhibited a ≥2‑fold change in threshold cycle in PC3 cells following 0.5% SM treatment. Functional gene grouping analysis demonstrated that SM treatment modulated the RNA transcription of approximately 18.4% of CAMs and 33.93% of ECM‑related genes. Quantitative PCR analysis showed that SM treatment led to a significant decrease in transcription levels of the following genes: Collagen 5 α‑1(V), connective tissue growth factor, integrin β‑2, kallmann syndrome 1, laminin α 3, matrix metallopeptidase 7 (MMP7), MMP13, secreted protein acidic cysteine‑rich, thrombospondin‑2 and versican; and that SM significantly increased the transcription levels of MMP2 and MMP12. Furthermore, MMP2 knockdown significantly reduced the migration of SM‑treated PC3 cells. The present study provides novel insights into the association of cigarette smoking with PCa progression, via the alteration of ECM/CAM interactions.

  13. Modulation of Cell Adhesion and Migration by the Histone Methyltransferase Subunit mDpy-30 and Its Interacting Proteins

    PubMed Central

    Xia, Bin; Joubert, Alexandra; Groves, Benjamin; Vo, Kevin; Ashraf, Davin; Djavaherian, Derek; Awe, Jason; Xiong, Ying; Cherfils, Jacqueline; Ma, Dzwokai

    2010-01-01

    We have previously shown that a subset of mDpy-30, an accessory subunit of the nuclear histone H3 lysine 4 methyltransferase (H3K4MT) complex, also localizes at the trans-Golgi network (TGN), where its recruitment is mediated by the TGN-localized ARF guanine nucleotide exchange factor (ArfGEF) BIG1. Depletion of mDpy-30 inhibits the endosome-to-TGN transport of internalized CIMPR receptors and concurrently promotes their accumulation at the cell protrusion. These observations suggest mDpy-30 may play a novel role at the crossroads of endosomal trafficking, nuclear transcription and adhesion/migration. Here we provide novel mechanistic and functional insight into this association. First, we demonstrate a direct interaction between mDpy-30 and BIG1 and locate the binding region in the N-terminus of BIG1. Second, we provide evidence that the depletion or overexpression of mDpy-30 enhances or inhibits cellular adhesion/migration of glioma cells in vitro, respectively. A similar increase in cell adhesion/migration is observed in cells with reduced levels of BIG1 or other H3K4MT subunits. Third, knockdown of mDpy-30, BIG1, or the RbBP5 H3K4MT subunit increases the targeting of β1 integrin to cell protrusions, and suppression of H3K4MT activity by depleting mDpy-30 or RbBP5 leads to increased protein and mRNA levels of β1 integrin. Moreover, stimulation of cell adhesion/migration via mDpy-30 knockdown is abolished after treating cells with a function-blocking antibody to β1 integrin. Taken together, these data indicate that mDpy-30 and its interacting proteins function as a novel class of cellular adhesion/migration modulators partially by affecting the subcellular distribution of endosomal compartments as well as the expression of key adhesion/migration proteins such as β1 integrin. PMID:20668708

  14. Modulation of eosinophil generation and migration by Mangifera indica L. extract (Vimang).

    PubMed

    Sá-Nunes, Anderson; Rogerio, Alexandre P; Medeiros, Alexandra I; Fabris, Viciany E; Andreu, Gilberto P; Rivera, Dagmar G; Delgado, René; Faccioli, Lúcia H

    2006-09-01

    The effects of Vimang, an aqueous extract of the stem bark of Mangifera indica L. (Anacardiaceae), on cell migration in an experimental model of asthma was investigated. In vivo treatment of Toxocara canis-infected BALB/c mice for 18 days with 50 mg/kg Vimang reduced eosinophil migration into the bronchoalveolar space and peritoneal cavity. Also, eosinophil generation in bone marrow and blood eosinophilia were inhibited in infected mice treated with Vimang. This reduction was associated with inhibition of IL-5 production in serum and eotaxin in lung homogenates. In all these cases the effects of Vimang were more selective than those observed with dexamethasone. Moreover, Vimang treatment is not toxic for the animals, as demonstrated by the normal body weight increase during infection. These data confirm the potent anti-inflammatory effect of Vimang and support its potential use as an alternative therapeutic drug to the treatment of eosinophilic disorders including those caused by nematodes and allergic diseases.

  15. LGL1 modulates proliferation, apoptosis, and migration of human fetal lung fibroblasts.

    PubMed

    Zhang, Hui; Sweezey, Neil B; Kaplan, Feige

    2015-02-15

    Rapid growth and formation of new gas exchange units (alveogenesis) are hallmarks of the perinatal lung. Bronchopulmonary dysplasia (BPD), common in very premature infants, is characterized by premature arrest of alveogenesis. Mesenchymal cells (fibroblasts) regulate both lung branching and alveogenesis through mesenchymal-epithelial interactions. Temporal or spatial deficiency of late-gestation lung 1/cysteine-rich secretory protein LD2 (LGL1/CRISPLD2), expressed in and secreted by lung fibroblasts, can impair both lung branching and alveogenesis (LGL1 denotes late gestation lung 1 protein; LGL1 denotes the human gene; Lgl1 denotes the mouse/rat gene). Absence of Lgl1 is embryonic lethal. Lgl1 levels are dramatically reduced in oxygen toxicity rat models of BPD, and heterozygous Lgl1(+/-) mice exhibit features resembling human BPD. To explore the role of LGL1 in mesenchymal-epithelial interactions in developing lung, we developed a doxycycline (DOX)-inducible RNA-mediated LGL1 knockdown cellular model in human fetal lung fibroblasts (MRC5(LGL1KD)). We assessed the impact of LGL1 on cell proliferation, cell migration, apoptosis, and wound healing. DOX-induced MRC5(LGL1KD) suppressed cell growth and increased apoptosis of annexin V(+) staining cells and caspase 3/7 activity. LGL1-conditioned medium increased migration of fetal rat primary lung epithelial cells and human airway epithelial cells. Impaired healing by MRC5(LGL1KD) cells of a wound model was attenuated by addition of LGL1-conditioned medium. Suppression of LGL1 was associated with dysregulation of extracellular matrix genes (downregulated MMP1, ColXVα1, and ELASTIN) and proapoptosis genes (upregulated BAD, BAK, CASP2, and TNFRSF1B) and inhibition of 44/42MAPK phosphorylation. Our findings define a role for LGL1 in fibroblast expansion and migration, epithelial cell migration, and mesenchymal-epithelial signaling, key processes in fetal lung development.

  16. CCN1: a novel inflammation-regulated biphasic immune cell migration modulator.

    PubMed

    Löbel, Madlen; Bauer, Sandra; Meisel, Christian; Eisenreich, Andreas; Kudernatsch, Robert; Tank, Juliane; Rauch, Ursula; Kühl, Uwe; Schultheiss, Heinz-Peter; Volk, Hans-Dieter; Poller, Wolfgang; Scheibenbogen, Carmen

    2012-09-01

    In this study, we performed a comprehensive analysis of the effect of CCN1 on the migration of human immune cells. The molecule CCN1, produced by fibroblasts and endothelial cells, is considered as an important matrix protein promoting tissue repair and immune cell adhesion by binding various integrins. We recently reported that CCN1 therapy is able to suppress acute inflammation in vivo. Here, we show that CCN1 binds to various immune cells including T cells, B cells, NK cells, and monocytes. The addition of CCN1 in vitro enhances both actin polymerization and transwell migration. Prolonged incubation with CCN1, however, results in the inhibition of migration of immune cells by a mechanism that involves downregulation of PI3Kγ, p38, and Akt activation. Furthermore, we observed that immune cells themselves produce constitutively CCN1 and secretion is induced by pro-inflammatory stimuli. In line with this finding, patients suffering from acute inflammation had enhanced serum levels of CCN1. These findings extend the classical concept of CCN1 as a locally produced cell matrix adhesion molecule and suggest that CCN1 plays an important role in regulating immune cell trafficking by attracting and locally immobilizing immune cells.

  17. Migration of interfacial oxygen ions modulated resistive switching in oxide-based memory devices

    NASA Astrophysics Data System (ADS)

    Chen, C.; Gao, S.; Zeng, F.; Tang, G. S.; Li, S. Z.; Song, C.; Fu, H. D.; Pan, F.

    2013-07-01

    Oxides-based resistive switching memory induced by oxygen ions migration is attractive for future nonvolatile memories. Numerous works had focused their attentions on the sandwiched oxide materials for depressing the characteristic variations, but the comprehensive studies of the dependence of electrodes on the migration behavior of oxygen ions are overshadowed. Here, we investigated the interaction of various metals (Ni, Co, Al, Ti, Zr, and Hf) with oxygen atoms at the metal/Ta2O5 interface under electric stress and explored the effect of top electrode on the characteristic variations of Ta2O5-based memory device. It is demonstrated that chemically inert electrodes (Ni and Co) lead to the scattering switching characteristics and destructive gas bubbles, while the highly chemically active metals (Hf and Zr) formed a thick and dense interfacial intermediate oxide layer at the metal/Ta2O5 interface, which also degraded the resistive switching behavior. The relatively chemically active metals (Al and Ti) can absorb oxygen ions from the Ta2O5 film and avoid forming the problematic interfacial layer, which is benefit to the formation of oxygen vacancies composed conduction filaments in Ta2O5 film thus exhibit the minimum variations of switching characteristics. The clarification of oxygen ions migration behavior at the interface can lead further optimization of resistive switching performance in Ta2O5-based memory device and guide the rule of electrode selection for other oxide-based resistive switching memories.

  18. Navigator-3, a modulator of cell migration, may act as a suppressor of breast cancer progression

    PubMed Central

    Cohen-Dvashi, Hadas; Ben-Chetrit, Nir; Russell, Roslin; Carvalho, Silvia; Lauriola, Mattia; Nisani, Sophia; Mancini, Maicol; Nataraj, Nishanth; Kedmi, Merav; Roth, Lee; Köstler, Wolfgang; Zeisel, Amit; Yitzhaky, Assif; Zylberg, Jacques; Tarcic, Gabi; Eilam, Raya; Wigelman, Yoav; Will, Rainer; Lavi, Sara; Porat, Ziv; Wiemann, Stefan; Ricardo, Sara; Schmitt, Fernando; Caldas, Carlos; Yarden, Yosef

    2015-01-01

    Dissemination of primary tumor cells depends on migratory and invasive attributes. Here, we identify Navigator-3 (NAV3), a gene frequently mutated or deleted in human tumors, as a regulator of epithelial migration and invasion. Following induction by growth factors, NAV3 localizes to the plus ends of microtubules and enhances their polarized growth. Accordingly, NAV3 depletion trimmed microtubule growth, prolonged growth factor signaling, prevented apoptosis and enhanced random cell migration. Mathematical modeling suggested that NAV3-depleted cells acquire an advantage in terms of the way they explore their environment. In animal models, silencing NAV3 increased metastasis, whereas ectopic expression of the wild-type form, unlike expression of two, relatively unstable oncogenic mutants from human tumors, inhibited metastasis. Congruently, analyses of > 2,500 breast and lung cancer patients associated low NAV3 with shorter survival. We propose that NAV3 inhibits breast cancer progression by regulating microtubule dynamics, biasing directionally persistent rather than random migration, and inhibiting locomotion of initiated cells. PMID:25678558

  19. Modulation of CD86 expression in skin dendritic cells does not always correlate with changes in DC motility, migration and allostimulatory functions.

    PubMed

    Bechetoille, Nicolas; Boher, Aurélie; Gaydon, Amandine; Andre-Frei, Valérie

    2010-01-01

    CD86 expression is a well-known activation marker of dendritic cells (DC). In this study, we compared the level of CD86 expression in monocyte-derived skin DC with their motility, migratory abilities and allostimulatory capabilities. We show that motility and migration could be uncoupled from activation and that the immune response-modulating effects of certain compounds may correlate with down-regulation of CD86 expression rather than with effects on motility and migration.

  20. The Wnt gatekeeper SFRP4 modulates EMT, cell migration and downstream Wnt signalling in serous ovarian cancer cells.

    PubMed

    Ford, Caroline E; Jary, Eve; Ma, Sean Si Qian; Nixdorf, Sheri; Heinzelmann-Schwarz, Viola A; Ward, Robyn L

    2013-01-01

    Aberrant Wnt signalling is implicated in numerous human cancers, and understanding the effects of modulation of pathway members may lead to the development of novel therapeutics. Expression of secreted frizzled related protein 4 (SFRP4), an extracellular modulator of the Wnt signalling pathway, is progressively lost in more aggressive ovarian cancer phenotypes. Here we show that recombinant SFRP4 (rSFRP4) treatment of a serous ovarian cancer cell line results in inhibition of β-catenin dependent Wnt signalling as measured by TOP/FOP Wnt reporter assay and decreased transcription of Wnt target genes, Axin2, CyclinD1 and Myc. In addition, rSFRP4 treatment significantly increased the ability of ovarian cancer cells to adhere to collagen and fibronectin, and decreased their ability to migrate across an inflicted wound. We conclude that these changes in cell behaviour may be mediated via mesenchymal to epithelial transition (MET), as rSFRP4 treatment also resulted in increased expression of the epithelial marker E-cadherin, and reduced expression of Vimentin and Twist. Combined, these results indicate that modulation of a single upstream gatekeeper of Wnt signalling can have effects on downstream Wnt signalling and ovarian cancer cell behaviour, as mediated through epithelial to mesenchymal plasticity (EMP). This raises the possibility that SFRP4 may be used both diagnostically and therapeutically in epithelial ovarian cancer.

  1. Melanoma Cell Adhesion and Migration Is Modulated by the Uronyl 2-O Sulfotransferase

    PubMed Central

    Nikolovska, Katerina; Spillmann, Dorothe; Haier, Jörg; Ladányi, Andrea; Stock, Christian; Seidler, Daniela G.

    2017-01-01

    Although the vast majority of melanomas are characterized by a high metastatic potential, if detected early, melanoma can have a good prognostic outcome. However, once metastasised, the prognosis is bleak. We showed previously that uronyl-2-O sulfotransferase (Ust) and 2-O sulfation of chondroitin/dermatan sulfate (CS/DS) are involved in cell migration. To demonstrate an impact of 2-O sulfation in metastasis we knocked-down Ust in mouse melanoma cells. This significantly reduced the amount of Ust protein and enzyme activity. Furthermore, in vitro cell motility and adhesion were significantly reduced correlating with the decrease of cellular Ust protein. Single cell migration of B16VshUst(16) cells showed a decreased cell movement phenotype. The adhesion of B16V cells to fibronectin depended on α5β1 but not αvβ3 integrin. Inhibition of glycosaminoglycan sulfation or blocking fibroblast growth factor receptor (FgfR) reduced α5 integrin in B16V cell lines. Interestingly, FgfR1 expression and activation was reduced in Ust knock-down cells. In vivo, pulmonary metastasis of B16VshUst cells was prevented due to a reduction of α5 integrin. As a proof of concept UST knock-down in human melanoma cells also showed a reduction in ITGa5 and adhesion. This is the first study showing that Ust, and consequently 2-O sulfation of the low affinity receptor for FgfR CS/DS, reduces Itga5 and leads to an impaired adhesion and migration of melanoma cells. PMID:28107390

  2. Modulation of the leptin receptor mediates tumor growth and migration of pancreatic cancer cells.

    PubMed

    Mendonsa, Alisha M; Chalfant, Madeleine C; Gorden, Lee D; VanSaun, Michael N

    2015-01-01

    Obesity has been implicated as a significant risk factor for development of pancreatic cancer. In the setting of obesity, a systemic chronic inflammatory response is characterized by alterations in the production and secretion of a wide variety of growth factors. Leptin is a hormone whose level increases drastically in the serum of obese patients. High fat diet induced obesity in mice leads to an overall increased body weight, pancreatic weight, serum leptin, and pancreatic tissue leptin levels. Here we report the contribution of obesity and leptin to pancreatic cancer growth utilizing an in vivo orthotopic murine pancreatic cancer model, which resulted in increased tumor proliferation with concomitant increased tumor burden in the diet induced obese mice compared to lean mice. Human and murine pancreatic cancer cell lines were found to express the short as well as the long form of the leptin receptor and functionally responded to leptin induced activation through an increased phosphorylation of AKT473. In vitro, leptin stimulation increased cellular migration which was blocked by addition of a PI3K inhibitor. In vivo, depletion of the leptin receptor through shRNA knockdown partially abrogated increased orthotopic tumor growth in obese mice. These findings suggest that leptin contributes to pancreatic tumor growth through activation of the PI3K/AKT pathway, which promotes pancreatic tumor cell migration.

  3. Modulation of the Leptin Receptor Mediates Tumor Growth and Migration of Pancreatic Cancer Cells

    PubMed Central

    Chalfant, Madeleine C.; Gorden, Lee D.

    2015-01-01

    Obesity has been implicated as a significant risk factor for development of pancreatic cancer. In the setting of obesity, a systemic chronic inflammatory response is characterized by alterations in the production and secretion of a wide variety of growth factors. Leptin is a hormone whose level increases drastically in the serum of obese patients. High fat diet induced obesity in mice leads to an overall increased body weight, pancreatic weight, serum leptin, and pancreatic tissue leptin levels. Here we report the contribution of obesity and leptin to pancreatic cancer growth utilizing an in vivo orthotopic murine pancreatic cancer model, which resulted in increased tumor proliferation with concomitant increased tumor burden in the diet induced obese mice compared to lean mice. Human and murine pancreatic cancer cell lines were found to express the short as well as the long form of the leptin receptor and functionally responded to leptin induced activation through an increased phosphorylation of AKT473. In vitro, leptin stimulation increased cellular migration which was blocked by addition of a PI3K inhibitor. In vivo, depletion of the leptin receptor through shRNA knockdown partially abrogated increased orthotopic tumor growth in obese mice. These findings suggest that leptin contributes to pancreatic tumor growth through activation of the PI3K/AKT pathway, which promotes pancreatic tumor cell migration. PMID:25919692

  4. Photonic modulation of EGFR: 280nm low level light arrests cancer cell activation and migration

    NASA Astrophysics Data System (ADS)

    Botelho, Cláudia M.; Marques, Rogério; Viruthachalam, Thiagarajan; Gonçalves, Odete; Vorum, Henrik; Gomes, Andreia C.; Neves-Petersen, Maria Teresa

    2017-02-01

    Overexpression of the Epidermal Growth Factor Receptor (EGFR) by cancer cells is associated with a poor prognosis for the patient. For several decades, therapies targeting EGFR have been designed, including the use of monoclonal antibodies and small molecule tyrosine kinase inhibitors. The use of these molecules had good clinical results, although its efficiency (and specificity) is still far from being optimal. In this paper, we present a new approach for a possible new cancer therapy targeting EGFR and using low intensity 280nm light. The influence of 280nm UVB illumination on cancer cells stimulated with 2nM of EGF was followed by time-lapse confocal microscopy. The 280nm illumination of the cancer cells blocks EGFR activation, inhibiting EGFR internalization and cell migration thus inhibiting the transition to the metastatic phenotype. Exposure time is a very important factor. The higher the illumination time the more significant differences were observed: 280nm light delayed or completely halted EGFR activation in the cell membrane, mainly at the cell junction level, and delayed or halted EGFR endocytic internalization, filopodia formation and cell migration.

  5. TRAF4 Is a Novel Phosphoinositide-Binding Protein Modulating Tight Junctions and Favoring Cell Migration

    PubMed Central

    Rousseau, Adrien; McEwen, Alastair G.; Poussin-Courmontagne, Pierre; Rognan, Didier; Nominé, Yves; Rio, Marie-Christine; Tomasetto, Catherine; Alpy, Fabien

    2013-01-01

    Tumor necrosis factor (TNF) receptor-associated factor 4 (TRAF4) is frequently overexpressed in carcinomas, suggesting a specific role in cancer. Although TRAF4 protein is predominantly found at tight junctions (TJs) in normal mammary epithelial cells (MECs), it accumulates in the cytoplasm of malignant MECs. How TRAF4 is recruited and functions at TJs is unclear. Here we show that TRAF4 possesses a novel phosphoinositide (PIP)-binding domain crucial for its recruitment to TJs. Of interest, this property is shared by the other members of the TRAF protein family. Indeed, the TRAF domain of all TRAF proteins (TRAF1 to TRAF6) is a bona fide PIP-binding domain. Molecular and structural analyses revealed that the TRAF domain of TRAF4 exists as a trimer that binds up to three lipids using basic residues exposed at its surface. Cellular studies indicated that TRAF4 acts as a negative regulator of TJ and increases cell migration. These functions are dependent from its ability to interact with PIPs. Our results suggest that TRAF4 overexpression might contribute to breast cancer progression by destabilizing TJs and favoring cell migration. PMID:24311986

  6. Transmembrane Collagen XVII Modulates Integrin Dependent Keratinocyte Migration via PI3K/Rac1 Signaling

    PubMed Central

    Löffek, Stefanie; Sigloch, Florian Christoph; Schilling, Oliver; Tasanen, Kaisa; Bruckner-Tuderman, Leena; Franzke, Claus-Werner

    2014-01-01

    The hemidesmosomal transmembrane component collagen XVII (ColXVII) plays an important role in the anchorage of the epidermis to the underlying basement membrane. However, this adhesion protein seems to be also involved in the regulation of keratinocyte migration, since its expression in these cells is strongly elevated during reepithelialization of acute wounds and in the invasive front of squamous cell carcinoma, while its absence in ColXVII-deficient keratinocytes leads to altered cell motility. Using a genetic model of murine Col17a1−/− keratinocytes we elucidated ColXVII mediated signaling pathways in cell adhesion and migration. Col17a1−/− keratinocytes exhibited increased spreading on laminin 332 and accelerated, but less directed cell motility. These effects were accompanied by increased expression of the integrin subunits β4 and β1. The migratory phenotype, as evidenced by formation of multiple unstable lamellipodia, was associated with enhanced phosphoinositide 3-kinase (PI3K) activity. Dissection of the signaling pathway uncovered enhanced phosphorylation of the β4 integrin subunit and the focal adhesion kinase (FAK) as activators of PI3K. This resulted in elevated Rac1 activity as a downstream consequence. These results provide mechanistic evidence that ColXVII coordinates keratinocyte adhesion and directed motility by interfering integrin dependent PI3K activation and by stabilizing lamellipodia at the leading edge of reepithelializing wounds and in invasive squamous cell carcinoma. PMID:24505282

  7. PREX2 promotes the proliferation, invasion and migration of pancreatic cancer cells by modulating the PI3K signaling pathway

    PubMed Central

    Yang, Jianyi; Gong, Xuejun; Ouyang, Lu; He, Wen; Xiao, Rou; Tan, Li

    2016-01-01

    Phosphatidylinositol-3,4,5-trisphosphate-dependent Rac exchanger factor 2 (PREX2) is a novel regulator of the small guanosine triphosphatase Rac, and has been observed to be implicated in human cancer by inhibiting the activity of phosphatase and tensin homolog (PTEN), thus upregulating the activity of the phosphoinositide 3-kinase (PI3K) signaling pathway. However, the exact role of PREX2 in pancreatic cancer has not been reported to date. In the present study, the expression levels of PREX2 were observed to be frequently increased in pancreatic cancer specimens compared with those in their matched adjacent normal tissues. In addition, PREX2 expression was also frequently upregulated in several pancreatic cancer cell lines, including AsPC-1, BxPC-3, PANC-1 and CFAPC-1, compared with that in the normal pancreatic epithelial cell line HPC-Y5. Overexpression of PREX2 significantly promoted the proliferation, invasion and migration of pancreatic cancer PANC-1 cells, while small interfering RNA-induced knockdown of PREX2 expression significantly inhibited the proliferation, invasion and migration of these cells. Investigation of the molecular mechanism revealed that the overexpression of PREX2 upregulated the phosphorylation levels of PTEN, indicating that the activity of PTEN was reduced, which further increased the phosphorylation levels of AKT, which indicated that the activity of the PI3K signaling pathway was upregulated. By contrast, knockdown of PREX2 upregulated the activity of PTEN and inhibited the activity of the PI3K signaling pathway. In conclusion, the present study demonstrated that PREX2 regulates the proliferation, invasion and migration of pancreatic cancer cells, probably at least via modulation of the activity of PTEN and the PI3K signaling pathway. PMID:27446408

  8. Main pathways of action of Brazilian red propolis on the modulation of neutrophils migration in the inflammatory process.

    PubMed

    Bueno-Silva, Bruno; Franchin, Marcelo; Alves, Claudiney de Freitas; Denny, Carina; Colón, David Fernando; Cunha, Thiago Mattar; Alencar, Severino Matias; Napimoga, Marcelo Henrique; Rosalen, Pedro Luiz

    2016-12-01

    Brazilian propolis is popularly used as treatment for different diseases including the ones with inflammatory origin. Brazilian red propolis chemical profile and its anti-inflammatory properties were recently described however, its mechanism of action has not been investigated yet. Elucidate Brazilian red propolis major pathways of action on the modulation of neutrophil migration during the inflammatory process. The ethanolic extract of propolis (EEP) activity was investigated for neutrophil migration into the peritoneal cavity, intravital microscopy (rolling and adhesion of leukocytes), quantification of cytokines TNF-α, IL-1β and chemokines CXCL1/KC, CXCL2/MIP-2, neutrophil chemotaxis induced by CXCL2/MIP-2, calcium influx and CXCR2 expression on neutrophils. EEP at 10mg/kg prevented neutrophil migration into peritoneal cavity (p < 0.05), reduced leukocyte rolling and adhesion on the mesenteric microcirculation (p < 0.05) and inhibited the release TNF-α, IL-1β, CXCL1/KC and CXCL2/MIP-2 (p < 0.05). EEP at 0.01, 0.1 and 1µg/ml reduced the CXCL2/MIP-2-induced neutrophils chemotaxis (p < 0.05) without affect cell viability (p > 0.05).EEP at 1µg/ml decreased the calcium influx induced by CXCL2/MIP-2 (p<0.05). On the other hand, none of EEP concentrations tested altered CXCR2 expression by neutrophils (p>0.05). Brazilian red propolis appears as a promising anti-inflammatory natural product which mechanism seems to be by reducing leukocyte rolling and adhesion; TNF-α, IL-1β, CXCL1/KC and CXCL2/MIP-2 release; CXCL2/MIP-2-induced chemotaxis and calcium influx. Copyright © 2016 Elsevier GmbH. All rights reserved.

  9. Kindlin-2 Modulates the Survival, Differentiation, and Migration of Induced Pluripotent Cell-Derived Mesenchymal Stromal Cells

    PubMed Central

    Eggenschwiler, Reto; Wichmann, Christian; Buhmann, Raymund; Cantz, Tobias

    2017-01-01

    Kindlin-2 is a multidomain intracellular protein that can be recruited to β-integrin domains to activate signaling, initiate transcriptional programs, and bind to E-cadherin. To explore its involvement in cell fate decisions in mesenchymal cells, we studied the effects of Kindlin-2 modification (overexpression/knockdown) in induced pluripotent cell-derived mesenchymal stromal cells (iPSC-MSCs). Kindlin-2 overexpression resulted in increased proliferation and reduced apoptosis of iPSC-MSCs, as well as inhibition of their differentiation towards osteocytes, adipocytes, and chondrocytes. In contrast, siRNA-mediated Kindlin-2 knockdown induced increased apoptosis and increased differentiation response in iPSC-MSCs. The ability of iPSC-MSCs to adhere to VCAM-1/SDF-1α under shear stress and to migrate in a wound scratch assay was significantly increased after Kindlin-2 overexpression. In contrast, inhibition of mixed lymphocyte reaction (MLR) was generally independent of Kindlin-2 modulation in iPSC-MSCs, except for decreased production of interleukin-2 (IL-2) after Kindlin-2 overexpression in iPS-MSCs. Thus, Kindlin-2 upregulates survival, proliferation, stemness, and migration potential in iPSC-MSCs and may therefore be beneficial in optimizing performance of iPSC-MSC in therapies. PMID:28163724

  10. The Pseudomonas aeruginosa N-Acylhomoserine Lactone Quorum Sensing Molecules Target IQGAP1 and Modulate Epithelial Cell Migration

    PubMed Central

    Karlsson, Thommie; Turkina, Maria V.; Yakymenko, Olena; Magnusson, Karl-Eric; Vikström, Elena

    2012-01-01

    Quorum sensing (QS) signaling allows bacteria to control gene expression once a critical population density is achieved. The Gram-negative human pathogen Pseudomonas aeruginosa uses N-acylhomoserine lactones (AHL) as QS signals, which coordinate the production of virulence factors and biofilms. These bacterial signals can also modulate human cell behavior. Little is known about the mechanisms of the action of AHL on their eukaryotic targets. Here, we found that N-3-oxo-dodecanoyl-L-homoserine lactone 3O-C12-HSL modulates human intestinal epithelial Caco-2 cell migration in a dose- and time-dependent manner. Using new 3O-C12-HSL biotin and fluorescently-tagged probes for LC-MS/MS and confocal imaging, respectively, we demonstrated for the first time that 3O-C12-HSL interacts and co-localizes with the IQ-motif-containing GTPase-activating protein IQGAP1 in Caco-2 cells. The interaction between IQGAP1 and 3O-C12-HSL was further confirmed by pull-down assay using a GST-tagged protein with subsequent Western blot of IQGAP1 and by identifying 3O-C12-HSL with a sensor bioassay. Moreover, 3O-C12-HSL induced changes in the phosphorylation status of Rac1 and Cdc42 and the localization of IQGAP1 as evidenced by confocal and STED microscopy and Western blots. Our findings suggest that the IQGAP1 is a novel partner for P.aeruginosa 3O-C12-HSL and likely the integrator of Rac1 and Cdc42- dependent altered cell migration. We propose that the targeting of IQGAP1 by 3O-C12-HSL can trigger essential changes in the cytoskeleton network and be an essential component in bacterial – human cell communication. PMID:23071436

  11. Sphingosine 1-phosphate and human ether-a'-go-go-related gene potassium channels modulate migration in human anaplastic thyroid cancer cells.

    PubMed

    Asghar, Muhammad Yasir; Viitanen, Tero; Kemppainen, Kati; Törnquist, Kid

    2012-10-01

    Anaplastic thyroid cancer (ATC) is the most aggressive form of human thyroid cancer, lacking any effective treatment. Sphingosine 1-phosphate (S1P) receptors and human ether-a'-go-go-related gene (HERG (KCNH2)) potassium channels are important modulators of cell migration. In this study, we have shown that the S1P(1-3) receptors are expressed in C643 and THJ-16T human ATC cell lines, both at mRNA and protein level. S1P inhibited migration of these cells and of follicular FTC-133 thyroid cancer cells. Using the S1P(1,3) inhibitor VPC-23019, the S1P(2) inhibitor JTE-013, and the S1P(2) receptor siRNA, we showed that the effect was mediated through S1P(2). Treatment of the cells with the Rho inhibitor C3 transferase abolished the effect of S1P on migration. S1P attenuated Rac activity, and inhibiting Rac decreased migration. Sphingosine kinase inhibitor enhanced basal migration of cells, and addition of exogenous S1P inhibited migration. C643 cells expressed a nonconducting HERG protein, and S1P decreased HERG protein expression. The HERG blocker E-4031 decreased migration. Interestingly, downregulating HERG protein with siRNA decreased the basal migration. In experiments using HEK cells overexpressing HERG, we showed that S1P decreased channel protein expression and current and that S1P attenuated migration of the cells. We conclude that S1P attenuates migration of C643 ATC cells by activating S1P(2) and the Rho pathway. The attenuated migration is also, in part, dependent on a S1P-induced decrease of HERG protein.

  12. Troglitazone inhibits cell migration, adhesion, and spreading by modulating cytoskeletal rearrangement in human breast cancer cells.

    PubMed

    Wang, Pei-Shan; Chou, Fu-Sheng; Porchia, Leonardo; Saji, Motoyasu; Pinzone, Joseph J

    2008-12-01

    Metastatic tumors are the primary cause of death in patients with breast cancer. Recent data indicate that the peroxisome proliferator-activated receptor gamma (PPARgamma) ligands, thiazolidinediones (TZDs), possess anti-invasive activities on human breast cancer cells. However, the effects of TZDs on other metastatic properties of breast cancer cells such as adhesion, spreading, and migration are not well established. In this study, we show that troglitazone (TG), a member of the TZD family, inhibits lamellipodia formation or membrane ruffling as well as actin polymerization at these structures in MDA-MB-231 and T47D breast cancer cells. In addition, TG reduces migration, adhesion, and spreading on fibronectin (FN)-coated plates. These phenomena were associated with the dramatic decrease of Tyr397 and Tyr576 phosphorylation of focal adhesion kinase (FAK) and the detergent-insoluble Rac1. We also found that TG upregulates Tyr416 phosphorylation of Src, but downregulates the Src-FAK complex. Moreover, we use a PPARgamma-inactive derivative of TG (STG28) and a PPARgamma antagonist (GW9662) to eliminate PPARgamma-mediated effects. We found that treatment with STG28 or GW9662 plus TG showed similar effects compared to TG treatment alone on tyrosine phosphorylation of FAK and Src, indicating that these effects are not the result of PPARgamma activation. Interestingly, we found that TG upregulates actin filament assembly at the point of cell-cell contact in T47D cells, indicating that TG may also upregulate cell-cell adhesion in breast cancer cells which express E-cadherin. These results suggested that TG should be investigated further for its therapeutic potential in metastatic breast cancer.

  13. Semaphorin 3A Increases FAK Phosphorylation at Focal Adhesions to Modulate MDA-MB-231 Cell Migration and Spreading on Different Substratum Concentrations

    PubMed Central

    Compere, Frances V.; Miller, Alex M.

    2017-01-01

    Interactions between integrin-mediated adhesions and the extracellular matrix (ECM) are important regulators of cell migration and spreading. However, mechanisms by which extracellular ligands regulate cell migration and spreading in response to changes in substratum concentration are not well understood. Semaphorin 3A (Sema3A) has been shown to inhibit cell motility and alter integrin signaling in various cell types. We propose that Sema3A alters focal adhesions to modulate breast carcinoma cell migration and spreading on substrata coated with different concentrations of ECM. We demonstrate that Sema3A inhibits MDA-MB-231 cell migration and spreading on substrata coated with high concentrations of collagen and fibronectin but enhances migration and spreading at lower concentrations of collagen and fibronectin. Sema3A increases focal adhesion kinase phosphorylation at tyrosine 397 (pFAK397) at focal adhesions on all substratum concentrations of collagen and fibronectin but decreased pFAK397 levels on laminin. Rho-associated protein kinase (ROCK) inhibition blocks the Sema3A-mediated effects on cell migration, spreading, and pFAK397 at focal adhesions when cultured on all concentrations of collagen. These results suggest that Sema3A shifts the optimal level of cell-matrix adhesions to a nonoptimal ECM coating concentration, in particular collagen, to yield maximal cell migration and spreading that may be mediated through a ROCK-dependent mechanism. PMID:28182100

  14. A Leishmania Ortholog of Macrophage Migration Inhibitory Factor Modulates Host Macrophage Responses

    SciTech Connect

    Kamir,D.; Zierow, S.; Leng, L.; Cho, Y.; Diaz, Y.; Griffith, J.; McDonald, C.; Merk, M.; Mitchell, R.; et al

    2008-01-01

    Parasitic organisms have evolved specialized strategies to evade immune defense mechanisms. We describe herein an ortholog of the cytokine, macrophage migration inhibitory factor (MIF), which is produced by the obligate intracellular parasite, Leishmania major. The Leishmania MIF protein, Lm1740MIF, shows significant structural homology with human MIF as revealed by a high-resolution x-ray crystal structure (1.03 A). Differences between the two proteins in the N-terminal tautomerization site are evident, and we provide evidence for the selective, species-specific inhibition of MIF by small-molecule antagonists that target this site. Lm1740MIF shows significant binding interaction with the MIF receptor, CD74 (K(d) = 2.9 x 10(-8) M). Like its mammalian counterpart, Lm1740MIF induces ERK1/2 MAP kinase activation in a CD74-dependent manner and inhibits the activation-induced apoptosis of macrophages. The ability of Lm1740MIF to inhibit apoptosis may facilitate the persistence of Leishmania within the macrophage and contribute to its evasion from immune destruction.

  15. Cell proliferation and migration are modulated by Cdk-1-phosphorylated endothelial-monocyte activating polypeptide II.

    PubMed

    Schwarz, Margaret A; Thornton, Janet; Xu, Haiming; Awasthi, Niranjan; Schwarz, Roderich E

    2012-01-01

    Endothelial-Monocyte Activating Polypeptide (EMAP II) is a secreted protein with well-established anti-angiogenic activities. Intracellular EMAP II expression is increased during fetal development at epithelial/mesenchymal boundaries and in pathophysiologic fibroproliferative cells of bronchopulmonary dysplasia, emphysema, and scar fibroblast tissue following myocardial ischemia. Precise function and regulation of intracellular EMAP II, however, has not been explored to date. Here we show that high intracellular EMAP II suppresses cellular proliferation by slowing progression through the G2M cell cycle transition in epithelium and fibroblast. Furthermore, EMAP II binds to and is phosphorylated by Cdk1, and exhibits nuclear/cytoplasmic partitioning, with only nuclear EMAP II being phosphorylated. We observed that extracellular secreted EMAP II induces endothelial cell apoptosis, where as excess intracellular EMAP II facilitates epithelial and fibroblast cells migration. Our findings suggest that EMAP II has specific intracellular effects, and that this intracellular function appears to antagonize its extracellular anti-angiogenic effects during fetal development and pulmonary disease progression.

  16. A Leishmania Ortholog of Macrophage Migration Inhibitory Factor Modulates Host Macrophage Responses1

    PubMed Central

    Kamir, Daniela; Zierow, Swen; Leng, Lin; Cho, Yoonsang; Diaz, Yira; Griffith, Jason; McDonald, Courtney; Merk, Melanie; Mitchell, Robert A.; Trent, John; Chen, Yibang; Kwong, Yuen-Kwan Amy; Xiong, Huabao; Vermeire, Jon; Cappello, Michael; McMahon-Pratt, Diane; Walker, John; Bernhagen, Jurgen; Lolis, Elias; Bucala, Richard

    2009-01-01

    Parasitic organisms have evolved specialized strategies to evade immune defense mechanisms. We describe herein an ortholog of the cytokine, macrophage migration inhibitory factor (MIF), which is produced by the obligate intracellular parasite, Leishmania major. The Leishmania MIF protein, Lm1740MIF, shows significant structural homology with human MIF as revealed by a high-resolution x-ray crystal structure (1.03 Å). Differences between the two proteins in the N-terminal tautomerization site are evident, and we provide evidence for the selective, species-specific inhibition of MIF by small-molecule antagonists that target this site. Lm1740MIF shows significant binding interaction with the MIF receptor, CD74 (Kd = 2.9 × 10−8 M). Like its mammalian counterpart, Lm1740MIF induces ERK1/2 MAP kinase activation in a CD74-dependent manner and inhibits the activation-induced apoptosis of macrophages. The ability of Lm1740MIF to inhibit apoptosis may facilitate the persistence of Leishmania within the macrophage and contribute to its evasion from immune destruction. PMID:18523291

  17. Light Emitting Diode-Generated Blue Light Modulates Fibrosis Characteristics: Fibroblast Proliferation, Migration Speed, and Reactive Oxygen Species Generation

    PubMed Central

    Mamalis, Andrew; Garcha, Manveer; Jagdeo, Jared

    2016-01-01

    Background and Objective Blue light is part of the visible light spectrum that does not generate harmful DNA adducts associated with skin cancer and photoaging, and may represent a safer therapeutic modality for treatment of keloid scars and other fibrotic skin diseases. Our laboratory previously demonstrated that light-emitting diode (LED) red and infrared light inhibits proliferation of skin fibroblasts. Moreover, different wavelengths of light can produce different biological effects. Furthermore, the effects of LED blue light (LED-BL) on human skin fibroblasts are not well characterized. This study investigated the effects of LED-BL on human skin fibroblast proliferation, viability, migration speed, and reactive oxygen-species (ROS) generation. Methods and Materials Irradiation of adult human skin fibroblasts using commercially-available LED-BL panels was performed in vitro, and modulation of proliferation and viability was quantified using the trypan blue dye exclusion assay, migratory speed was assessed using time-lapse video microscopy, and intracellular ROS generation was measured using the dihydrorhodamine flow cytometry assay. Statistical differences between groups were determined by ANOVA and Student s t-test. Results Human skin fibroblasts treated with LED-BL fluences of 5, 30, 45, and 80 J/cm2 demonstrated statistically significant dose-dependent decreases in relative proliferation of 8.4%, 29.1%, 33.8%, 51.7%, and 55.1%, respectively, compared to temperature and environment matched bench control plates, respectively. LED-BL fluences of 5, 30, 45 and 80 J/cm2 decreased fibroblast migration speed to 95 ± 7.0% (p = 0.64), 81.3 ± 5.5% (p = 0.021), 48.5 ± 2.7% (p < 0.0001), and 32.3 ± 1.9% (p < 0.0001), respectively, relative to matched controls. LED fluences of 5, 10, 30, and 80 J/cm2 resulted in statistically significant increases in reactive oxygen species of 110.4%, 116.6%, 127.5%, and 130%, respectively, relative to bench controls. Conclusion At

  18. Light emitting diode-generated blue light modulates fibrosis characteristics: fibroblast proliferation, migration speed, and reactive oxygen species generation.

    PubMed

    Mamalis, Andrew; Garcha, Manveer; Jagdeo, Jared

    2015-02-01

    Blue light is part of the visible light spectrum that does not generate harmful DNA adducts associated with skin cancer and photoaging, and may represent a safer therapeutic modality for treatment of keloid scars and other fibrotic skin diseases. Our laboratory previously demonstrated that light-emitting diode (LED) red and infrared light inhibits proliferation of skin fibroblasts. Moreover, different wavelengths of light can produce different biological effects. Furthermore, the effects of LED blue light (LED-BL) on human skin fibroblasts are not well characterized. This study investigated the effects of LED-BL on human skin fibroblast proliferation, viability, migration speed, and reactive oxygen-species (ROS) generation. Irradiation of adult human skin fibroblasts using commercially-available LED-BL panels was performed in vitro, and modulation of proliferation and viability was quantified using the trypan blue dye exclusion assay, migratory speed was assessed using time-lapse video microscopy, and intracellular ROS generation was measured using the dihydrorhodamine flow cytometry assay. Statistical differences between groups were determined by ANOVA and Student's t-test. Human skin fibroblasts treated with LED-BL fluences of 5, 10, 15, 30, and 80 J/cm(2) demonstrated statistically significant dose-dependent decreases in relative proliferation of 8.4%, 29.1%, 33.8%, 51.7%, and 55.1%, respectively, compared to temperature and environment matched bench control plates, respectively. LED-BL fluences of 5, 30, 45, and 80 J/cm(2) decreased fibroblast migration speed to 95 ± 7.0% (P = 0.64), 81.3 ± 5.5% (P = 0.021), 48.5 ± 2.7% (P < 0.0001), and 32.3 ± 1.9% (P < 0.0001), respectively, relative to matched controls. LED fluences of 5, 10, 30, and 80 J/cm(2) resulted in statistically significant increases in reactive oxygen species of 110.4%, 116.6%, 127.5%, and 130%, respectively, relative to bench controls. At the fluences

  19. An oyster species-specific miRNA scaffold42648_5080 modulates haemocyte migration by targeting integrin pathway.

    PubMed

    Chen, Hao; Wang, Hao; Jiang, Shuai; Xu, Jiachao; Wang, Lingling; Qiu, Limei; Song, Linsheng

    2016-10-01

    miRNAs are important gene regulators at post-transcriptional level and can modulate diverse biological processes, including immune response. Dozens of species-specific miRNAs have been identified in oyster Crassostrea gigas while their functions remain largely unknown. In the present study, an oyster species-specific miRNA scaffold42648_5080 was found responsive to LPS stimulation and might target a total of 31 oyster genes possibly involved in cell communication, cellular localization and cellular response to stimulus. Besides, in gain-of-function assay of scaffold42648_5080 in vivo, the phagocytosis (30.90% in miRNA group verse 23.20% in miRNA control group), apoptosis (3.10% in miRNA group verse 5.30% in miRNA control group) and migration rate (13.88% in miRNA group verse 21.03% in miRNA control group) of oyster haemocytes were found significantly altered after the injection of scaffold42648_5080 mimics. Among the target genes, integrin-linked kinase (CgILK) was considered crucial in cell migration and its interaction with scaffold42648_5080 was then verified both in vitro and in vivo. Consequently, a significant decrease of relative luciferase ratio was observed in CgILK 3'-UTR luciferase reporter assay after transfection of scaffold42648_5080 mimics (0.70-fold of that in blank group, p < 0.01). Meanwhile, when scaffold42648_5080 was overexpressed in vivo (5.41-fold of miRNA control group, p < 0.01), the expression of CgILK declined significantly to 0.25-fold of miRNA control group (p < 0.01). Comparatively, a significant decrease of the haemocyte migration rate (19.76% verse 34.82% in siEGFP control group, p < 0.01) was observed after knock-down of CgILK in vivo. The present study, as far as we know, for the first time revealed the immunomodulation role of an oyster species-specific miRNA, which might provide new insights into miRNA-mediated adaptation mechanism of oysters.

  20. Rac1 and Cdc42 differentially modulate cigarette smoke-induced airway cell migration through p120-catenin-dependent and -independent pathways.

    PubMed

    Zhang, Lili; Gallup, Marianne; Zlock, Lorna; Finkbeiner, Walter E; McNamara, Nancy A

    2013-06-01

    The adherens junction protein p120-catenin (p120ctn) shuttles between E-cadherin-bound and cytoplasmic pools to regulate E-cadherin/catenin complex stability and cell migration, respectively. When released from the adherens junction, p120ctn promotes cell migration through modulation of the Rho GTPases Rac1, Cdc42, and RhoA. Accordingly, the down-regulation and cytoplasmic mislocalization of p120ctn has been reported in all subtypes of lung cancers and is associated with grave prognosis. Previously, we reported that cigarette smoke induced cytoplasmic translocation of p120ctn and cell migration, but the underlying mechanism was unclear. Using primary human bronchial epithelial cells exposed to smoke-concentrated medium (Smk), we observed the translocation of Rac1 and Cdc42, but not RhoA, to the leading edge of polarized and migrating human bronchial epithelial cells. Rac1 and Cdc42 were robustly activated by smoke, whereas RhoA was inhibited. Accordingly, siRNA knockdown of Rac1 or Cdc42 completely abolished Smk-induced cell migration, whereas knockdown of RhoA had no effect. p120ctn/Rac1 double knockdown completely abolished Smk-induced cell migration, whereas p120ctn/Cdc42 double knockdown did not. These data suggested that Rac1 and Cdc42 coactivation was essential to smoke-promoted cell migration in the presence of p120ctn, whereas migration proceeded via Rac1 alone in the absence of p120ctn. Thus, Rac1 may provide an omnipotent therapeutic target in reversing cell migration during the early (intact p120ctn) and late (loss of p120ctn) stages of lung carcinogenesis.

  1. Modulation of eotaxin formation and eosinophil migration by selective inhibitors of phosphodiesterase type 4 isoenzyme

    PubMed Central

    Silva, Patrícia M R; Alves, Alessandra C; Serra, Magda F; Pires, Ana Lucia A; Silva, Juliane P; Barreto, Emiliano O; Cordeiro, Renato S B; Jose, Peter J; Teixeira, Mauro M; Lagente, Vincent; Martins, Marco A

    2001-01-01

    This study was undertaken to investigate the possible contribution of the blockade of eotaxin generation to the anti-eosinophilotactic effect of phosphodiesterase (PDE) type 4 inhibitors. In some experiments, the putative synergistic interaction between PDE type 4 inhibitors and the β2-agonist salbutamol was also assessed.Sensitized guinea-pigs aerosolized with antigen (5% ovalbumin, OVA) responded with a significant increase in eotaxin and eosinophil levels in the bronchoalveolar lavage fluid (BALF) at 6 h. Eosinophil recruitment was inhibited by both PDE type 4 inhibitors rolipram (5 mg kg−1, i.p.) and RP 73401 (5 mg kg−1, i.p.) treatments. In contrast, only rolipram inhibited eotaxin production.Sensitized rats intrapleurally challenged (i.pl.) with antigen (OVA, 12 μg cavity−1) showed a marked eosinophil infiltration at 24 h, preceded by eotaxin generation at 6 h. Intravenous administration of a rabbit anti-mouse eotaxin antibody (0.5 mg kg−1) significantly reduced allergen-evoked eosinophilia in this model.Local pretreatment with rolipram (40 μg cavity−1) or RP 73401 (40 μg cavity−1) 1 h before challenge reduced eosinophil accumulation evaluated in the rat pleural effluent, but only the former was active against eotaxin generation. The inhibitors of PDE type 3 (SK&F 94836) and type 5 (zaprinast) failed to alter allergen-evoked eosinophil recruitment in rats.Local injection of β2-agonist salbutamol (20 μg cavity−1) inhibited both eosinophil accumulation and eotaxin production following pleurisy. The former was better inhibited when salbutamol and rolipram were administered in combination.Treatment with rolipram and RP 73401 dose-dependently inhibited eosinophil adhesion and migration in vitro. These effects were clearly potentiated by salbutamol at concentrations that had no effect alone.Our findings indicate that although rolipram and RP 73401 are equally effective in inhibiting allergen-induced eosinophil

  2. The small heat shock protein B8 (HSPB8) modulates proliferation and migration of breast cancer cells.

    PubMed

    Piccolella, Margherita; Crippa, Valeria; Cristofani, Riccardo; Rusmini, Paola; Galbiati, Mariarita; Cicardi, Maria Elena; Meroni, Marco; Ferri, Nicola; Morelli, Federica F; Carra, Serena; Messi, Elio; Poletti, Angelo

    2017-02-07

    Breast cancer (BC) is one of the major causes of cancer death in women and is closely related to hormonal dysregulation. Estrogen receptor (ER)-positive BCs are generally treated with anti hormone therapy using antiestrogens or aromatase inhibitors. However, BC cells may become resistant to endocrine therapy, a process facilitated by autophagy, which may either promote or suppress tumor expansion. The autophagy facilitator HSPB8 has been found overexpressed in some BC. Here we found that HSPB8 is highly expressed and differentially modulated by natural or synthetic selective ER modulators (SERMs), in the triple-positive hormone-sensitive BC (MCF-7) cells, but not in triple-negative MDA-MB-231 BC cells. Specific SERMs induced MCF-7 cells proliferation in a HSPB8 dependent manner whereas, did not modify MDA-MB-231 cell growth. ER expression was unaffected in HSPB8-depleted MCF-7 cells. HSPB8 over-expression did not alter the distribution of MCF-7 cells in the various phases of the cell cycle. Conversely and intriguingly, HSPB8 downregulation resulted in an increased number of cells resting in the G0/G1 phase, thus possibly reducing the ability of the cells to pass through the restriction point. In addition, HSPB8 downregulation reduced the migratory ability of MCF-7 cells. None of these modifications were observed, when another small HSP (HSPB1), also expressed in MCF-7 cells, was downregulated. In conclusion, our data suggest that HSPB8 is involved in the mechanisms that regulate cell cycle and cell migration in MCF-7 cells.

  3. Inter-kingdom Signaling by the Legionella Quorum Sensing Molecule LAI-1 Modulates Cell Migration through an IQGAP1-Cdc42-ARHGEF9-Dependent Pathway.

    PubMed

    Simon, Sylvia; Schell, Ursula; Heuer, Natalie; Hager, Dominik; Albers, Michael F; Matthias, Jan; Fahrnbauer, Felix; Trauner, Dirk; Eichinger, Ludwig; Hedberg, Christian; Hilbi, Hubert

    2015-12-01

    Small molecule signaling promotes the communication between bacteria as well as between bacteria and eukaryotes. The opportunistic pathogenic bacterium Legionella pneumophila employs LAI-1 (3-hydroxypentadecane-4-one) for bacterial cell-cell communication. LAI-1 is produced and detected by the Lqs (Legionella quorum sensing) system, which regulates a variety of processes including natural competence for DNA uptake and pathogen-host cell interactions. In this study, we analyze the role of LAI-1 in inter-kingdom signaling. L. pneumophila lacking the autoinducer synthase LqsA no longer impeded the migration of infected cells, and the defect was complemented by plasmid-borne lqsA. Synthetic LAI-1 dose-dependently inhibited cell migration, without affecting bacterial uptake or cytotoxicity. The forward migration index but not the velocity of LAI-1-treated cells was reduced, and the cell cytoskeleton appeared destabilized. LAI-1-dependent inhibition of cell migration involved the scaffold protein IQGAP1, the small GTPase Cdc42 as well as the Cdc42-specific guanine nucleotide exchange factor ARHGEF9, but not other modulators of Cdc42, or RhoA, Rac1 or Ran GTPase. Upon treatment with LAI-1, Cdc42 was inactivated and IQGAP1 redistributed to the cell cortex regardless of whether Cdc42 was present or not. Furthermore, LAI-1 reversed the inhibition of cell migration by L. pneumophila, suggesting that the compound and the bacteria antagonistically target host signaling pathway(s). Collectively, the results indicate that the L. pneumophila quorum sensing compound LAI-1 modulates migration of eukaryotic cells through a signaling pathway involving IQGAP1, Cdc42 and ARHGEF9.

  4. Inter-kingdom Signaling by the Legionella Quorum Sensing Molecule LAI-1 Modulates Cell Migration through an IQGAP1-Cdc42-ARHGEF9-Dependent Pathway

    PubMed Central

    Simon, Sylvia; Schell, Ursula; Heuer, Natalie; Hager, Dominik; Albers, Michael F.; Matthias, Jan; Fahrnbauer, Felix; Trauner, Dirk; Eichinger, Ludwig; Hedberg, Christian; Hilbi, Hubert

    2015-01-01

    Small molecule signaling promotes the communication between bacteria as well as between bacteria and eukaryotes. The opportunistic pathogenic bacterium Legionella pneumophila employs LAI-1 (3-hydroxypentadecane-4-one) for bacterial cell-cell communication. LAI-1 is produced and detected by the Lqs (Legionella quorum sensing) system, which regulates a variety of processes including natural competence for DNA uptake and pathogen-host cell interactions. In this study, we analyze the role of LAI-1 in inter-kingdom signaling. L. pneumophila lacking the autoinducer synthase LqsA no longer impeded the migration of infected cells, and the defect was complemented by plasmid-borne lqsA. Synthetic LAI-1 dose-dependently inhibited cell migration, without affecting bacterial uptake or cytotoxicity. The forward migration index but not the velocity of LAI-1-treated cells was reduced, and the cell cytoskeleton appeared destabilized. LAI-1-dependent inhibition of cell migration involved the scaffold protein IQGAP1, the small GTPase Cdc42 as well as the Cdc42-specific guanine nucleotide exchange factor ARHGEF9, but not other modulators of Cdc42, or RhoA, Rac1 or Ran GTPase. Upon treatment with LAI-1, Cdc42 was inactivated and IQGAP1 redistributed to the cell cortex regardless of whether Cdc42 was present or not. Furthermore, LAI-1 reversed the inhibition of cell migration by L. pneumophila, suggesting that the compound and the bacteria antagonistically target host signaling pathway(s). Collectively, the results indicate that the L. pneumophila quorum sensing compound LAI-1 modulates migration of eukaryotic cells through a signaling pathway involving IQGAP1, Cdc42 and ARHGEF9. PMID:26633832

  5. Quaternary-Linked Changes in Structure and Dynamics That Modulate O2 Migration within Hemoglobin's Gas Diffusion Tunnels.

    PubMed

    Shadrina, Maria S; Peslherbe, Gilles H; English, Ann M

    2015-09-01

    Atomistic molecular dynamics simulations of diffusion of O2 from the hemes to the external solvent in the α- and β-subunits of the human hemoglobin (HbA) tetramer reveal transient gas tunnels that are not seen in crystal structures. We find here that the tunnel topology, which encompasses the reported experimental Xe binding cavities, is identical in HbA's T, R, and R2 quaternary states. However, the O2 population in the cavities and the preferred O2 escape portals vary significantly with quaternary structure. For example, most O2 molecules escape from the T β-subunit via the cavity at the center of the tetramer, but direct exit from the distal heme pocket dominates in the R2 β-subunit. To understand what triggers the quaternary-linked redistribution of O2 within its tunnels, we examined how the simulated tertiary structure and dynamics of each subunit differs among T, R, and R2 and report that minor adjustments in α-chain dynamics and β-heme position modulate O2 distribution and escape in HbA. Coupled to the β-heme position, residue βF71 undergoes quaternary-linked conformations that strongly regulate O2 migration between the β-subunit and HbA's central cavity. Remarkably, the distal histidine (HisE7) remains in a closed conformation near the α- and β-hemes in all states, but this does not prevent an average of 23, 31, and 46% of O2 escapes from the distal heme pockets of T, R, and R2, respectively, via several distal portals, with the balance of escapes occurring via the interior tunnels. Furthermore, preventing or restricting the access of O2 to selected cavities by mutating HisE7 and other heme pocket residues to tryptophan reveals how O2 migration adjusts to the bulky indole ring and sheds light on the experimental ligand binding kinetics of these variants. Overall, our simulations underscore the high gas porosity of HbA in its T, R, and R2 quaternary states and provide new mechanistic insights into why undergoing transitions among these states

  6. Nerve growth factor modulates the tumor cells migration in ovarian cancer through the WNT/β-catenin pathway

    PubMed Central

    Li, Bo; Cai, Shaoxi; Zhao, Yi; He, Qiyi; Yu, Xiaodong; Cheng, Longcong; Zhang, Yingfeng; Hu, Xiancheng; Ke, Ming; Chen, Sijia; Zou, Misha

    2016-01-01

    Nerve growth factor (NGF)/nerve growth factor receptors (NGFRs) axis and canonical WNT/β-catenin pathway have shown to play crucial roles in tumor initiation, progression and prognosis. But little did we know the relationship between them in modulation of tumor progress. In this report, we found that NGF/NGFRs and β-catenin were coexpression in ovarian cancer cell lines, and NGF can decrease the expression level of β-catenin and affect its activities, which may be related to the NGF-induced down-regulation of B-cell CLL/lymphoma 9-like (BCL9L, BCL9-2). Furthermore, NGF can also increase or decrease the downstream target gene expression levels of WNT/β-catenin depending on the cell types. Especially, we created a novel in vitro cell growth model based on a microfluidic device to intuitively observe the effects of NGF/NGFRs on the motility behaviors of ovarian cancer cells. The results showed that the migration area and maximum distance into three dimensional (3D) matrigel were decreased in CAOV3 and OVCAR3 cells, but increased in SKOV3 cells following the stimulation with NGF. In addition, we found that the cell colony area was down-regulated in CAOV3 cells, however, it was augmented in OVCAR3 cells after treatment with NGF. The inhibitors of NGF/NGFRs, such as Ro 08-2750, K252a and LM11A-31,can all block NGF-stimulated changes of gene expression or migratory behavior on ovarian cancer cells. The different results among ovarian cancer cells illustrated the heterogeneity and complexity of ovarian cancer. Collectively, our results suggested for the first time that NGF is functionally linked to β-catenin in the migration of human ovarian cancer cells, which may be a novel therapeutic perspective to prevent the spread of ovarian carcinomas by studying the interaction between NGF/NGFRs and canonical WNT/β-catenin signaling. PMID:27835587

  7. Hematopoietic PBX-interacting protein (HPIP) is over expressed in breast infiltrative ductal carcinoma and regulates cell adhesion and migration through modulation of focal adhesion dynamics.

    PubMed

    Bugide, S; David, D; Nair, A; Kannan, N; Samanthapudi, V S K; Prabhakar, J; Manavathi, B

    2015-08-27

    The scaffolding protein, hematopoietic PBX-interacting protein (HPIP/PBXIP1), regulates cell migration necessary for cancer cell dissemination. However, the mechanism that governs this process remains unknown. We show here that HPIP expression is associated with stages of breast cancer where cell dissemination results in poor patient outcome. Our investigation finds a novel association of HPIP with focal adhesion kinase (FAK) regulating FA dynamics. Interestingly, this interaction that led to activation of FAK protein was mediated by the C-terminal domain of HPIP and not the typical integrin-binding motif. Further, short hairpin RNA-mediated knockdown of FAK expression significantly reduced HPIP-induced cell migration indicating participation of FAK pathway. Live-cell time-lapse imaging and biochemical analysis further established the role of HPIP in microtubule-induced FA disassembly. We also found that HPIP-mediated MAPK activation led to phosphorylation and subsequent activation of calpain2, and the activated calpain2 in turn proteolyses FA protein, talin. Interestingly, HPIP is also proteolysed by calpain2 in breast cancer cells. The proteolysis of HPIP and talin by calpain2, and the activation of calapin2 by HPIP-mediated MAPK phosphorylation, is a novel regulatory axis to modulate the cell migration signal. Together, we have determined HPIP as a novel activator of FAK and a new substrate of calpain2. These molecular interactions between HPIP and FAK, and HPIP and calpain2 regulate cell adhesion and migration through modulation of FA dynamics.

  8. 7α-Hydroxypregnenolone, a key neuronal modulator of locomotion, stimulates upstream migration by means of the dopaminergic system in salmon.

    PubMed

    Haraguchi, Shogo; Yamamoto, Yuzo; Suzuki, Yuko; Hyung Chang, Joon; Koyama, Teppei; Sato, Miku; Mita, Masatoshi; Ueda, Hiroshi; Tsutsui, Kazuyoshi

    2015-07-29

    Salmon migrate upstream against an opposing current in their natal river. However, the molecular mechanisms that stimulate upstream migratory behavior are poorly understood. Here, we show that 7α-hydroxypregnenolone (7α-OH PREG), a newly identified neuronal modulator of locomotion, acts as a key factor for upstream migration in salmon. We first identified 7α-OH PREG and cytochrome P450 7α-hydroxylase (P4507α), a steroidogenic enzyme producing 7α-OH PREG, in the salmon brain and then found that 7α-OH PREG synthesis in the brain increases during upstream migration. Subsequently, we demonstrated that 7α-OH PREG increases upstream migratory behavior of salmon. We further found that 7α-OH PREG acts on dopamine neurons in the magnocellular preoptic nucleus during upstream migration. Thus, 7α-OH PREG stimulates upstream migratory behavior through the dopaminergic system in salmon. These findings provide new insights into the molecular mechanisms of fish upstream migration.

  9. The lutheran/basal cell adhesion molecule promotes tumor cell migration by modulating integrin-mediated cell attachment to laminin-511 protein.

    PubMed

    Kikkawa, Yamato; Ogawa, Takaho; Sudo, Ryo; Yamada, Yuji; Katagiri, Fumihiko; Hozumi, Kentaro; Nomizu, Motoyoshi; Miner, Jeffrey H

    2013-10-25

    Cell-matrix interactions are critical for tumor cell migration. Lutheran (Lu), also known as basal cell adhesion molecule (B-CAM), competes with integrins for binding to laminin α5, a subunit of LM-511, a major component of basement membranes. Here we show that the preferential binding of Lu/B-CAM to laminin α5 promotes tumor cell migration. The attachment of Lu/B-CAM transfectants to LM-511 was slightly weaker than that of control cells, and this was because Lu/B-CAM disturbed integrin binding to laminin α5. Lu/B-CAM induced a spindle cell shape with pseudopods and promoted cell migration on LM-511. In addition, blocking with an anti-Lu/B-CAM antibody led to a flat cell shape and inhibited migration on LM-511, similar to the effects of an activating integrin β1 antibody. We conclude that tumor cell migration on LM-511 requires that Lu/B-CAM competitively modulates cell attachment through integrins. We suggest that this competitive interaction is involved in a balance between static and migratory cell behaviors.

  10. The Lutheran/Basal Cell Adhesion Molecule Promotes Tumor Cell Migration by Modulating Integrin-mediated Cell Attachment to Laminin-511 Protein*

    PubMed Central

    Kikkawa, Yamato; Ogawa, Takaho; Sudo, Ryo; Yamada, Yuji; Katagiri, Fumihiko; Hozumi, Kentaro; Nomizu, Motoyoshi; Miner, Jeffrey H.

    2013-01-01

    Cell-matrix interactions are critical for tumor cell migration. Lutheran (Lu), also known as basal cell adhesion molecule (B-CAM), competes with integrins for binding to laminin α5, a subunit of LM-511, a major component of basement membranes. Here we show that the preferential binding of Lu/B-CAM to laminin α5 promotes tumor cell migration. The attachment of Lu/B-CAM transfectants to LM-511 was slightly weaker than that of control cells, and this was because Lu/B-CAM disturbed integrin binding to laminin α5. Lu/B-CAM induced a spindle cell shape with pseudopods and promoted cell migration on LM-511. In addition, blocking with an anti-Lu/B-CAM antibody led to a flat cell shape and inhibited migration on LM-511, similar to the effects of an activating integrin β1 antibody. We conclude that tumor cell migration on LM-511 requires that Lu/B-CAM competitively modulates cell attachment through integrins. We suggest that this competitive interaction is involved in a balance between static and migratory cell behaviors. PMID:24036115

  11. Sphingosine-1-phosphate/S1P receptors signaling modulates cell migration in human bone marrow-derived mesenchymal stem cells.

    PubMed

    Kong, Yaxian; Wang, Hong; Lin, Tao; Wang, Shuling

    2014-01-01

    The recruitment of bone marrow-derived mesenchymal stem cells (BMSCs) to damaged tissues and sites of inflammation is an essential step for clinical therapy. However, the signals regulating the motility of these cells are still not fully understood. Sphingosine-1-phosphate (S1P), a bioactive sphingolipid metabolite, is known to have a variety of biological effects on various cells. Here, we investigated the roles of S1P and S1P receptors (S1PRs) in migration of human BMSCs. We found that S1P exerted a powerful migratory action on human BMSCs. Moreover, by employing RNA interference technology and pharmacological tools, we demonstrated that S1PR1 and S1PR3 are responsible for S1P-induced migration of human BMSCs. In contrast, S1PR2 mediates the inhibition of migration. Additionally, we explored the downstream signaling pathway of the S1P/S1PRs axis and found that activation of S1PR1 or S1PR3 increased migration of human BMSCs through a G i /extracellular regulated protein kinases 1/2- (ERK1/2-) dependent pathway, whereas activation of S1PR2 decreased migration through the Rho/Rho-associated protein kinase (ROCK) pathway. In conclusion, we reveal that the S1P/S1PRs signaling axis regulates the migration of human BMSCs via a dual-directional mechanism. Thus, selective modulation of S1PR's activity on human BMSCs may provide an effective approach to immunotherapy or tissue regeneration.

  12. LGR4 Is a Direct Target of MicroRNA-34a and Modulates the Proliferation and Migration of Retinal Pigment Epithelial ARPE-19 Cells

    PubMed Central

    Hou, Qiang; Zhou, Linglin; Tang, Jiajia; Ma, Nan; Xu, Ancong; Tang, Jiang; Zheng, Dandan; Chen, Xiaogang; Chen, Feng; Dong, Xiang Da; Tu, LiLi

    2016-01-01

    The pathology of proliferative vitreoretinopathy and proliferative diabetic retinopathy is linked to proliferation, migration, and adhesion of the retinal pigment epithelium. MicroRNA-34a (miR-34a) expression modulates changes in proliferation and migration of retinal pigment epithelial cell line ARPE-19. In this study, we determined that miR-34a interacts with LGR4, identified by bioinformatics using TargetScan Human 5.0, to affect these changes. Double luciferase gene reporter assay confirmed miR-34a involvement in mediating control. miR-34a mimic transfection decreased LGR4 expression. Western blot analysis documented corresponding protein expression inhibition. MTS, Ki67 immunostaining, scratch and transwell testing, along with attachment assay showed that miR-34a upregulation inhibited ARPE-19 cell proliferation, migration and attachment partly through downregulation of LGR4 protein expression. Western blot analysis revealed that both miR-34a upregulation and LGR4 downregulation induced declines in E2F1, p-CDC2, CDK2, CDK4 and CDK6 protein expression. Taken together, miR-34a gene expression upregulation inhibits ARPE-19 cell proliferation, migration and adhesion partly by suppressing LGR4 expression. These results substantiate earlier indications that both miR-34a and LGR4 are potential drug targets to prevent fibrosis in a clinical setting. PMID:27977785

  13. LGR4 Is a Direct Target of MicroRNA-34a and Modulates the Proliferation and Migration of Retinal Pigment Epithelial ARPE-19 Cells.

    PubMed

    Hou, Qiang; Zhou, Linglin; Tang, Jiajia; Ma, Nan; Xu, Ancong; Tang, Jiang; Zheng, Dandan; Chen, Xiaogang; Chen, Feng; Dong, Xiang Da; Tu, LiLi

    2016-01-01

    The pathology of proliferative vitreoretinopathy and proliferative diabetic retinopathy is linked to proliferation, migration, and adhesion of the retinal pigment epithelium. MicroRNA-34a (miR-34a) expression modulates changes in proliferation and migration of retinal pigment epithelial cell line ARPE-19. In this study, we determined that miR-34a interacts with LGR4, identified by bioinformatics using TargetScan Human 5.0, to affect these changes. Double luciferase gene reporter assay confirmed miR-34a involvement in mediating control. miR-34a mimic transfection decreased LGR4 expression. Western blot analysis documented corresponding protein expression inhibition. MTS, Ki67 immunostaining, scratch and transwell testing, along with attachment assay showed that miR-34a upregulation inhibited ARPE-19 cell proliferation, migration and attachment partly through downregulation of LGR4 protein expression. Western blot analysis revealed that both miR-34a upregulation and LGR4 downregulation induced declines in E2F1, p-CDC2, CDK2, CDK4 and CDK6 protein expression. Taken together, miR-34a gene expression upregulation inhibits ARPE-19 cell proliferation, migration and adhesion partly by suppressing LGR4 expression. These results substantiate earlier indications that both miR-34a and LGR4 are potential drug targets to prevent fibrosis in a clinical setting.

  14. Ganglioside GM2 mediates migration of tumor cells by interacting with integrin and modulating the downstream signaling pathway.

    PubMed

    Kundu, Manjari; Mahata, Barun; Banerjee, Avisek; Chakraborty, Sohini; Debnath, Shibjyoti; Ray, Sougata Sinha; Ghosh, Zhumur; Biswas, Kaushik

    2016-07-01

    The definitive role of ganglioside GM2 in mediating tumor-induced growth and progression is still unknown. Here we report a novel role of ganglioside GM2 in mediating tumor cell migration and uncovered its mechanism. Data shows differential expression levels of GM2-synthase as well as GM2 in different human cancer cells. siRNA mediated knockdown of GM2-synthase in CCF52, A549 and SK-RC-26B cells resulted in significant inhibition of tumor cell migration as well as invasion in vitro without affecting cellular proliferation. Over-expression of GM2-synthase in low-GM2 expressing SK-RC-45 cells resulted in a consequent increase in migration thus confirming the potential role GM2 and its downstream partners play in tumor cell migration and motility. Further, treatment of SK-RC-45 cells with exogenous GM2 resulted in a dramatic increase in migratory and invasive capacity with no change in proliferative capacity, thereby confirming the role of GM2 in tumorigenesis specifically by mediating tumor migration and invasion. Gene expression profiling of GM2-synthase silenced cells revealed altered expression of several genes involved in cell migration primarily those controlling the integrin mediated signaling. GM2-synthase knockdown resulted in decreased phosphorylation of FAK, Src as well as Erk, while over-expression and/or exogenous GM2 treatment caused increased FAK and Erk phosphorylation respectively. Again, GM2 mediated invasion and Erk phosphorylation is blocked in integrin knockdown SK-RC-45 cells, thus confirming that GM2 mediated migration and phosphorylation of Erk is integrin dependent. Finally, confocal microscopy suggested co-localization while co-immunoprecipitation and surface plasmon resonance (SPR) confirmed direct interaction of membrane bound ganglioside, GM2 with the integrin receptor. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Pyrogallol abates VSMC migration via modulation of Caveolin-1, matrix metalloproteinase and intima hyperplasia in carotid ligation mouse.

    PubMed

    Ma, Yu-Dong; Thiyagarajan, Varadharajan; Tsai, May-Jywan; Lue, Sheng-I; Chia, Yi-Chen; Shyue, Song-Kun; Weng, Ching-Feng

    2016-12-01

    Migration of vascular smooth muscle cells (VSMCs) contributes to intimal hyperplasia and other vascular diseases. Caveolin-1 (Cav-1) has been recognized as a proliferative inhibitor of VSMCs and is likely to be an important regulator of VSMC migration. The underlying mechanism of pyrogallol on the VSMC migration is not fully understood. This study attempted to dissect the role of Cav-1 and matrix metalloproteinase (MMP) in VSMC migration and to investigate the effect of pyrogallol on VSMC mobility during carotid artery ligation mice. The mRNA expression of MMP-3 and MMP-13 was down-regulated in cultured VSMC prepared from Cav-1-deficient (Cav-1 KO) mice whereas MMP-14 expression was up-regulated. Pyrogallol effectively inhibited the migration of Cav-1 KO VSMC by promoting the expression of tissue inhibitors of metalloproteinase (TIMP)-2. Pyrogallol also inhibited the migration of Cav-1 wild type (WT) VSMC, however, by increasing TIMP-1 expression and repressing MMP-2 activity. In a parallel in vivo study, intra-peritoneal (ip) of pyrogallol to carotid artery ligated mice significantly suppressed intima formation in mice carotid artery. Furthermore, the proMMP-9 activity in pyrogallol-treated mice serum significantly increased from Day 0 to Day 2 and decreased from Day 2 to Day 7 in a time-dependent manner. In addition, WT mice treated with pyrogallol had significantly reduced neointima formation, whereas no differences were observed in Cav-1 knock out (KO) mice. These results suggest that pyrogallol not only inhibited VSMC migration but also effectively diminishes the severity of neointima hyperplasia, implying that pyrogallol possesses potential anti-atherogenic effects for the treatment of vascular diseases.

  16. Japanese Migration and the Americas: An Introduction to the Study of Migration.

    ERIC Educational Resources Information Center

    Mukai, Gary; Brunette, Rachel

    This curriculum module introduces students to the study of migration, including a brief overview of some categories of migration and reasons why people migrate. As a case study, the module uses the Japanese migration experience in the United States, Peru, Brazil, Canada, Mexico, Argentina, Bolivia, and Paraguay. The module introduces students to…

  17. Fibronectin Modulates Cell Adhesion and Signaling to Promote Single Cell Migration of Highly Invasive Oral Squamous Cell Carcinoma

    PubMed Central

    Ramos, Grasieli de Oliveira; Bernardi, Lisiane; Lauxen, Isabel; Sant’Ana Filho, Manoel; Horwitz, Alan Rick; Lamers, Marcelo Lazzaron

    2016-01-01

    Cell migration is regulated by adhesion to the extracellular matrix (ECM) through integrins and activation of small RhoGTPases, such as RhoA and Rac1, resulting in changes to actomyosin organization. During invasion, epithelial-derived tumor cells switch from laminin-enriched basal membrane to collagen and fibronectin-enriched connective tissue. How this switch affects the tumor migration is still unclear. We tested the hypothesis that ECM dictates the invasiveness of Oral Squamous Cell Carcinoma (OSCC). We analyzed the migratory properties of two OSCC lines, a low invasive cell line with high e-cadherin levels (Linv/HE-cad) or a highly invasive cell line with low e-cadherin levels (Hinv/LE-cad), plated on different ECM components. Compared to laminin, fibronectin induced non-directional collective migration and decreased RhoA activity in Linv/HE-cad OSCC. For Hinv/LE-cad OSCC, fibronectin increased Rac1 activity and induced smaller adhesions, resulting in a fast single cell migration in both 2D and 3D environments. Consistent with these observations, human OSCC biopsies exhibited similar changes in cell-ECM adhesion distribution at the invasive front of the tumor, where cells encounter fibronectin. Our results indicate that ECM composition might induce a switch from collective to single cell migration according to tumor invasiveness due to changes in cell-ECM adhesion and the resulting signaling pathways that alter actomyosin organization. PMID:26978651

  18. Evidence that activation of ASIC1a by acidosis increases osteoclast migration and adhesion by modulating integrin/Pyk2/Src signaling pathway.

    PubMed

    Li, X; Ye, J-X; Xu, M-H; Zhao, M-D; Yuan, F-L

    2017-07-01

    Activated acid-sensing ion channel 1a (ASIC1a) is involved in acid-induced osteoclastogenesis by regulating activation of the transcription factor NFATc1. These results indicated that ASIC1a activation by extracellular acid may cause osteoclast migration and adhesion through Ca(2+)-dependent integrin/Pyk2/Src signaling pathway. Osteoclast adhesion and migration are responsible for osteoporotic bone loss. Acidic conditions promote osteoclastogenesis. ASIC1a in osteoclasts is associated with acid-induced osteoclastogenesis through modulating transcription factor NFATc1 activation. However, the influence and the detailed mechanism of ASIC1a in regulating osteoclast adhesion and migration, in response to extracellular acid, are not well characterized. In this study, knockdown of ASIC1a was achieved in bone marrow macrophage cells using small interfering RNA (siRNA). The adhesion and migration abilities of osteoclast precursors and osteoclasts were determined by adhesion and migration assays, in vitro. Bone resorption was performed to measure osteoclast function. Cytoskeletal changes were assessed by F-actin ring formation. αvβ3 integrin expression in osteoclasts was measured by flow cytometry. Western blotting and co-immunoprecipitation were performed to measure alterations in integrin/Pyk2/Src signaling pathway. Our results showed that blockade of ASIC1a using ASIC1a-siRNA inhibited acid-induced osteoclast precursor migration and adhesion, as well as osteoclast adhesion and bone resorption; we also demonstrated that inhibition of ASIC1a decreased the cell surface αvβ3 integrin and β3 protein expression. Moreover, blocking of ASIC1a inhibited acidosis-induced actin ring formation and reduced Pyk2 and Src phosphorylation in osteoclasts and also inhibited the acid-induced association of the αvβ3 integrin/Src/Pyk2. Together, these results highlight a key functional role of ASIC1a/αvβ3 integrin/Pyk2/Src signaling pathway in migration and adhesion of osteoclasts.

  19. Nerve terminal effects of indoleamine psychotomimetics on 5-hydroxytryptamine.

    PubMed

    Halaris, A E

    1982-01-01

    The mode of action of indoleamine psychotomimetics has been closely linked to 5-HT. Early work showed increases in rat brain levels of 5-HT which were later localized to the nerve-ending fraction. With improved methodology, the 5-HT increment was further detected in the synaptic vesicle fraction. These effects were obtained with several indoleamine hallucinogens but not with mescaline. LSD has been most thoroughly studied and has served as the prototypical compound in ascertaining the mode of action of these drugs. Pretreatment with reserpine abolished the 5-HT effects of LSD in the vesicular fraction. However, a new compartment, termed "juxtavesicular," displayed 5-HT increases following reserpine and LSD. A soluble binding site for 5-HT within the synaptoplasm has been postulated in confirmation of independent results by other groups of investigators. The origin of the 5-HT increment appears to be associated with newly synthesized amine. This was deduced from experiments involving various 5-HT synthesis blockers. To ascertain whether inhibition of raphé neuronal firing is responsible for the accumulation of 5-HT at the nerve terminal, two sets of experiments were performed. Destruction of the raphé cell bodies by radiofrequency lesions failed to abolish the LSD-induced 5-HT increase early after the lesion. Destruction of cortical 5-HT neurons with the neurotoxin 5,7-dihydroxytryptamine completely abolished the 5-HT effect of LSD. It was concluded that an intact nerve terminal is necessary for the expression of the LSD-mediated increases in 5-HT. A LSD "autoreceptor" is postulated, possibly identical to a 5-HT presynaptic receptor inhibiting the release of 5-HT.

  20. Implication of acidic lipids in 5-hydroxytryptamine receptor mechanisms

    SciTech Connect

    Yoshikawa, S.; Ishitani, R.

    1985-02-04

    To establish the possible involvement of acidic lipids in 5-HT receptor mechanisms, the authors subjected whole rat brain synaptic plasma membranes to treatment with several kinds of lipid-modifying reagents and examined the (/sup 3/H)5-HT and (/sup 3/H)spiperone binding properties of the membranes. (/sup 3/H)5-HT binding was decreased by treatment with Azure A, while (/sup 3/H)spiperone binding was not altered. Similarly, prior treatment with arylsulphatase reduced the former binding, but had no effect on the latter binding. On the other hand, neither (/sup 3/H)ligand binding was sensitive to phospholipases C and D. In contrast, prior treatment with phospholipase A/sub 2/ (unheated) drastically decreased the (/sup 3/H)5-HT binding and also affected the (/sup 3/H)spiperone binding to some extent. Chelation of Ca/sup 2 +/ by EGTA (5 mM) prior to incubation of membranes with the unheated phospholipase A/sub 2/ did not completely prevent the inhibitory effect of this enzyme on (/sup 3/H)5-HT binding, while in the heated enzyme (at 100/sup 0/C for 10 min) EGTA exhibited this preventive effect perfectly. Furthermore, it was an interesting find that at least a low concentration of the heated phospholipase A/sub 2/ (0.01 U) had no effect on the (/sup 3/H)spiperone binding, as contrasted with the case of (/sup 3/H)5-HT binding. In addition, the reduction of (/sup 3/H)5-HT binding capacity in membranes treated with phospholipase A/sub 2/ (heated and unheated) was restored only slightly by treatment with BSA (1%). 17 references, 4 tables.

  1. Participation of 5-hydroxytryptamine in anticonvulsive action of benzodiazepines.

    PubMed

    Kleinrok, Z; Przegaliński, E; Czuczwar, S

    1977-01-01

    The influence of several compounds activating or producing hypofunction of the serotonergic system was studied on the convulsive threshold and anticonvulsive action of benzodiazepines (chlordiazepoxide, diazepam, oxazepam, nitrazepam) in the pentylenetetrazol test. No changes in the convulsive threshold either for clonic, nor for tonic phase were found. However, the anticonvulsive action of benzodiazepines was enhanced by 5-hydroxytryptophan, 5-methoxytryptamine (given together with pargyline), or fenfluramine. p-Chlorophenylalanine and methergoline did not affect, but cyproheptadine enhanced the anticonvulsive action of most of benzodiazepines tested.

  2. Phosphorylation of BRN2 Modulates Its Interaction with the Pax3 Promoter To Control Melanocyte Migration and Proliferation

    PubMed Central

    Berlin, Irina; Denat, Laurence; Steunou, Anne-Lise; Puig, Isabel; Champeval, Delphine; Colombo, Sophie; Roberts, Karen; Bonvin, Elise; Bourgeois, Yveline; Davidson, Irwin; Delmas, Véronique; Nieto, Laurence; Goding, Colin R.

    2012-01-01

    MITF-M and PAX3 are proteins central to the establishment and transformation of the melanocyte lineage. They control various cellular mechanisms, including migration and proliferation. BRN2 is a POU domain transcription factor expressed in melanoma cell lines and is involved in proliferation and invasion, at least in part by regulating the expression of MITF-M and PAX3. The T361 and S362 residues of BRN2, both in the POU domain, are conserved throughout the POU protein family and are targets for phosphorylation, but their roles in vivo remain unknown. To examine the role of this phosphorylation, we generated mutant BRN2 in which these two residues were replaced with alanines (BRN2TS→BRN2AA). When expressed in melanocytes in vitro or in the melanocyte lineage in transgenic mice, BRN2TS induced proliferation and repressed migration, whereas BRN2AA repressed both proliferation and migration. BRN2TS and BRN2AA bound and repressed the MITF-M promoter, whereas PAX3 transcription was induced by BRN2TS but repressed by BRN2AA. Expression of the BRN2AA transgene in a Mitf heterozygous background and in a Pax3 mutant background enhanced the coat color phenotype. Our findings show that melanocyte migration and proliferation are controlled both through the regulation of PAX3 by nonphosphorylated BRN2 and through the regulation of MITF-M by the overall BRN2 level. PMID:22290434

  3. A novel 3D bone-mimetic scaffold composed of collagen/MTA/MWCNT modulates cell migration and osteogenesis.

    PubMed

    Valverde, Thalita M; Castro, Elisandra G; Cardoso, Maíssa H S; Martins-Júnior, Paulo A; Souza, Lívia M O; Silva, Patrícia P; Ladeira, Luiz O; Kitten, Gregory T

    2016-10-01

    This study characterized a three-dimensional (3D) biocomposite scaffolds produced using type I collagen, mineral trioxide aggregate (MTA) and multi-walled carbon nanotubes (MWCNT) to be used in bone tissue regeneration. The scaffolds were analyzed via scanning (SEM) and transmission (TEM) electron microscopy, as well as the viability and migration of osteoblasts and mineralization of the scaffolds. SEM and TEM analyses showed that MTA and MWCNT were distributed as both large agglomerates entrapped within the collagen network and as smaller accumulations or individual molecules dispersed throughout the scaffold. Ultrastructural analysis revealed that osteoblastic MC3T3-E1 cells grown in the biocomposite endocytosed MWCNT, which were localized in the cytoplasm and in vesicles. Analysis of cells grown in the 3D scaffolds demonstrated that >95% of the cells remained viable in all tested combinations and concentrations of the biocomposite. MC3T3-E1 osteoblasts migrated into scaffolds formed with concentrations of type I collagen between 1.75 and 3.0mg/mL. Cells displayed increased migration into scaffolds formed with collagen and a range of low to high concentrations of MTA. In contrast, the presence of MWCNT in the biocomposite had a slight negative effect on migration. Collagen gels containing specific concentrations of MTA, or MWCNT, or combinations of MTA/MWCNT, caused an increase in mineralization of scaffolds. Scaffolds composed of defined concentrations of type I collagen, MTA and MWCNT are biocompatible, promote migration and mineralization of osteoblasts, and hence may be useful as bone tissue mimetics. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Regulation of miR-155 affects pancreatic cancer cell invasiveness and migration by modulating the STAT3 signaling pathway through SOCS1.

    PubMed

    Huang, Chen; Li, Haidong; Wu, Weidong; Jiang, Tao; Qiu, Zhengjun

    2013-09-01

    In the present study, we investigated the effects of miR-155 on pancreatic cancer cell invasion and migration in vitro, underlying gene expression, expression of miR-155 and its target genes in pancreatic cancer tissues, and their association with metastasis and clinical stage. miR-155 mimics and an inhibitor were transfected into Panc-1 and Capan-2 cells in order to regulate the expression of miR-155. qPCR and western immunoblotting were performed in order to detect gene expression. Transwell assays were performed to characterize the invasion and migration of pancreatic cancer cells in vitro. Immunohistochemical analysis and in situ hybridization were used to detect the expression of protein and microRNA in pancreatic cancer tissue. miR-155 mimics and an inhibitor upregulated and downregulated, respectively, the expression of miR-155 in pancreatic cancer cells. The invasion and migration of pancreatic cancer cells increased or decreased along with miR-155 expression in vitro. Suppressor of cytokine signaling 1 (SOCS1) protein expression was upregulated when miR-155 was inhibited and downregulated when miR-155 was increased. However, the expression of P-signal transducer and activator of transcription-3 (STAT3) was synchronized with that of miR-155. Transcription of SOCS1 and STAT3 was unchanged by miR-155 regulation. miR-155 expression was high in pancreatic cancer tissues and SOCS1 expression was high in tumor-adjacent tissues. There was no relationship between these genes in cancer and tumor-adjacent tissues. In addition, miR-155 expression was associated with lymph node metastasis and clinical stage. In conclusion, miR-155 plays an important role in the regulation of pancreatic cancer cell invasion and migration by modulating the STAT3 signaling pathway and reducing SOCS1 expression in pancreatic cancer cells.

  5. Differences in rapid desensitization of 5-hydroxytryptamine2A and 5-hydroxytryptamine2C receptor-mediated phospholipase C activation.

    PubMed

    Berg, K A; Stout, B D; Maayani, S; Clarke, W P

    2001-11-01

    The serotonin (5-HT)2A and 5-HT2C receptors share a high degree of sequence homology and have very similar pharmacological profiles. Although it is generally believed that the cellular signal transduction mechanisms activated by these receptors are indistinguishable, recent data suggest significant differences in their signaling cascades. In this study we explored differences in the characteristics and mechanisms of rapid desensitization between the 5-HT2A and 5-HT2C receptor systems. For both receptor systems, pretreatment with 5-HT reduced the ability of a maximal concentration of 5-HT to stimulate phospholipase C-mediated inositol phosphate accumulation by about 65%, although the 5-HT2C receptor system was more sensitive to the desensitizing stimulus. Differences in the concentration dependence of the rate constant for desensitization (k(des)) suggested different mechanisms of desensitization for the 5-HT2A and 5-HT2C receptor systems. At very high receptor occupancy (>99%), the responsiveness of the 5-HT2A, but not the 5-HT2C, receptor system returned to control levels despite the continued presence of the agonist. This resensitization was dependent upon the activity of protein kinase C (PKC). Agonist-induced desensitization of the 5-HT2A, but not the 5-HT2C, receptor system was reduced by the PKC inhibitors staurosporine and bisindolylmaleimide, and by down-regulation of PKC. In addition, inhibitors of calmodulin (W-7) or of calmodulin-dependent protein kinase II, reduced 5-HT2A, but not 5-HT2C, desensitization. Desensitization of the 5-HT2C, but not the 5-HT2A, receptor system was dependent on G protein receptor kinase activity. These data further emphasize the major differences in the signaling systems coupled to 5-HT2A/2C receptors.

  6. NDUFV2 regulates neuronal migration in the developing cerebral cortex through modulation of the multipolar-bipolar transition.

    PubMed

    Chen, Tianda; Wu, Qinwei; Zhang, Yang; Zhang, Dai

    2015-11-02

    Abnormalities during brain development are tightly linked several psychiatric disorders. Mutations in NADH dehydrogenase ubiquinone flavoprotein 2 (NDUFV2) are responsible for schizophrenia, bipolar disorder and Parkinson׳s disease. However, the function of NDUFV2 during brain development remains unclear. Here we reported that ndufv2 is expressed in the developing cerebral cortex. In utero suppression of ndufv2 arrested neuronal migration, leading to accumulation of ectopic neurons in the intermediate zone. ndufv2 inhibition did not affect radial glia scaffold, progenitor cells or neurons survival. However, the loss of ndufv2 impairs neuronal multipolar-bipolar transition in vivo and polarization in vitro. Moreover, ndufv2 affected actin cytoskeleton and tubulin stabilization in cortical neurons. Overall, our findings establish a new NDUFV2 dependent mechanism underlying neuronal migration and psychiatric disorders.

  7. Inhibition of miR-664a interferes with the migration of osteosarcoma cells via modulation of MEG3.

    PubMed

    Sahin, Yunus; Altan, Zekiye; Arman, Kaifee; Bozgeyik, Esra; Koruk Ozer, Meltem; Arslan, Ahmet

    2017-08-26

    Osteosarcoma is the most common primary bone tumor in children and adolescents. Understanding the basic molecular mechanisms in developing cancer can be helpful in developing alternative treatment strategies. The relationship between dysregulated non-coding RNAs' (ncRNA) expression level and osteosarcoma was detected. Among those ncRNAs, the expression levels of miR-664a were detected to be upregulated and MEG3 long non-coding RNA levels were detected to be downregulated in osteosarcoma tissue and cell lines. In this study, miR-664a inhibitor was used in order to investigate the changes in the expression levels of MEG3 gene and miR-664a in osteosarcoma cancer cell line (U2-OS) and human osteoblast cell line (hFOB 1.19). According to our results, the expression level of MEG3 gene was increased while the expression level of miR-664a was decreased, as expected. In addition, changes in expression level of MEG3 and miR-644a interferes with the migration of osteosarcoma cells migration speed of osteosarcoma cells. These results are found to be statistically significant (p < 0.05). As a result of this study, it was shown that the upregulated expression of miR-664a could have an inhibitory effect on MEG3 gene expression and migration of osteosarcoma cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Modulation of the uptake of critical nutrients by breast cancer cells by lactate: Impact on cell survival, proliferation and migration.

    PubMed

    Guedes, Marta; Araújo, João R; Correia-Branco, Ana; Gregório, Inês; Martel, Fátima; Keating, Elisa

    2016-02-15

    This work aimed to characterize the uptake of folate and glucose by breast cancer cells and to study the effect of lactate upon the transport of these nutrients and upon cell viability, proliferation and migration capacity. Data obtained showed that: a) MCF7 cells uptake (3)H-folic acid ((3)H-FA) at physiological but not at acidic pH; b) T47D cells accumulate (3)H-FA and (14)C-5-methyltetrahydrofolate ((14)C-5-MTHF) more efficiently at acidic than at physiological pH; c) (3)H-deoxyglucose ((3)H-DG) uptake by T47D cells is sodium-independent, inhibited by cytochalasin B (CYT B) and stimulated by insulin. Regarding the effect of lactate, in T47D cells, acute (26 min) and chronic (24 h) exposure to lactic acid (LA) stimulated (3)H-FA uptake. Acute exposure to LA also stimulated (3)H-DG uptake and chronic exposure to LA significantly stimulated T47D cell migratory capacity. In conclusion, the transport of folates is strikingly different in two phenotypically similar breast cancer cell lines: MCF7 and T47D cells. Additionally, lactate seems to act as a signaling molecule which increases the uptake of nutrients and promotes the migration capacity of T47D cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Transforming Growth Factor β Controls the Directional Migration of Hepatocyte Cohorts by Modulating Their Adhesion to Fibronectin

    PubMed Central

    Binamé, Fabien; Lassus, Patrice

    2008-01-01

    Transforming growth factor β (TGF-β) has a strong impact on liver development and physiopathology, exercised through its pleiotropic effects on growth, differentiation, survival, and migration. When exposed to TGF-β, the mhAT3F cells, immortalized, highly differentiated hepatocytes, maintained their epithelial morphology and underwent dramatic alterations of adhesion, leading to partial or complete detachment from a culture plate, followed by readhesion and spreading. These alterations of adhesive behavior were caused by sequential changes in expression of the α5β1 integrin and of its ligand, the fibronectin. The altered specificity of anchorage to the extracellular matrix gave rise to changes in cells' collective motility: cohorts adhering to fibronectin maintained a persistent, directional motility, with ezrin-rich pathfinder cells protruding from the tips of the cohorts. The absence of adhesion to fibronectin prevented the appearance of polarized pathfinders and lead to random, oscillatory motility. Our data suggest a novel role for TGF-β in the control of collective migration of epithelial cohorts. PMID:18094041

  10. Golgi phosphoprotein 2 (GOLPH2) is a novel bile acid-responsive modulator of oesophageal cell migration and invasion

    PubMed Central

    Byrne, Anne-Marie; Bekiaris, Spiros; Duggan, Gina; Prichard, David; Kirca, Murat; Finn, Stephen; Reynolds, John V; Kelleher, Dermot; Long, Aideen

    2015-01-01

    Background: The aetiology of Barrett's oesophagus (BO) and oesophageal cancer is poorly understood. We previously demonstrated that Golgi structure and function is altered in oesophageal cancer cells. A Golgi-associated protein, GOLPH2, was previously established as a tissue biomarker for BO. Cellular functions for GOLPH2 are currently unknown, therefore in this study we sought to investigate functional roles for this Golgi-associated protein in oesophageal disease. Methods: Expression, intracellular localisation and secretion of GOLPH2 were identified by immunofluorescence, immunohistochemistry and western blot. GOLPH2 expression constructs and siRNA were used to identify cellular functions for GOLPH2. Results: We demonstrate that the structure of the Golgi is fragmented and the intracellular localisation of GOLPH2 is altered in BO and oesophageal adenocarcinoma tissue. GOLPH2 is secreted by oesophageal cancer cells and GOLPH2 expression, cleavage and secretion facilitate cell migration and invasion. Furthermore, exposure of cells to DCA, a bile acid component of gastric refluxate and known tumour promoter for oesophageal cancer, causes disassembly of the Golgi structure into ministacks, resulting in cleavage and secretion of GOLPH2. Conclusions: This study demonstrates that GOLPH2 may be a useful tissue biomarker for oesophageal disease. We provide a novel mechanistic insight into the aetiology of oesophageal cancer and reveal novel functions for GOLPH2 in regulating tumour cell migration and invasion, important functions for the metastatic process in oesophageal cancer. PMID:26461057

  11. The Lnc RNA SPRY4-IT1 Modulates Trophoblast Cell Invasion and Migration by Affecting the Epithelial-Mesenchymal Transition

    PubMed Central

    Zuo, Qing; Huang, Shiyun; Zou, Yanfen; Xu, Yetao; Jiang, Ziyan; Zou, Shan; Xu, Haoqing; Sun, Lizhou

    2016-01-01

    Preeclampsia is a common, pregnancy-specific disease and a major contributor to maternal and foetal morbidity and mortality. Some placental abnormalities, including deficient implantation, abnormal trophoblast cell function, and improper placental vascular development, are believed to lead to preeclampsia. The long noncoding RNA SPRY4-IT1 is more highly expressed in preeclamptic human placentas than in normal placentas. We assessed the role of epithelial-mesenchymal transition (EMT)-associated invasion and migration in HTR-8/SVneo trophoblast cells. Overexpression of SPRY4-IT1 suppressed trophoblast cell migration and invasion, whereas reduced expression of SPRY4-IT1 prevented the EMT process. Mechanistically, an RNA immunoprecipitation experiment showed that SPRY4-IT1 bound directly to HuR and mediated the β-catenin expression associated with EMT in HTR-8/SVneo cells. Moreover, the expression levels of genes in the WNT family, such as WNT3 and WNT5B, were changed after transfection of HTR-8/SVneo with SPRY4-IT1. Together, our results highlight the roles of SPRY4-IT1 in causing trophoblast cell dysfunction by acting through the Wnt/β-catenin pathway, and consequently in impairing spiral artery remodelling. These results suggest a new potential therapeutic target for intervention against preeclampsia. PMID:27853262

  12. Human pancreatic stellate cells modulate 3D collagen alignment to promote the migration of pancreatic ductal adenocarcinoma cells.

    PubMed

    Drifka, Cole R; Loeffler, Agnes G; Esquibel, Corinne R; Weber, Sharon M; Eliceiri, Kevin W; Kao, W John

    2016-12-01

    A hallmark of pancreatic ductal adenocarcinoma (PDAC) is the ability for cancer cells to aggressively infiltrate and navigate through a dense stroma during the metastatic process. Key features of the PDAC stroma include an abundant population of activated pancreatic stellate cells (PSCs) and highly aligned collagen fibers; however, important questions remain regarding how collagen becomes aligned and what the biological manifestations are. To better understand how PSCs, aligned collagen, and PDAC cells might cooperate during the transition to invasion, we utilized a microchannel-based in vitro tumor model and advanced imaging technologies to recreate and examine in vivo-like heterotypic interactions. We found that PSCs participate in a collaborative process with cancer cells by orchestrating the alignment of collagen fibers that, in turn, are permissive to enhanced cell migration. Additionally, direct contact between PSCs, collagen, and PDAC cells is critical to invasion and co-migration of both cell types. This suggests PSCs may accompany and assist in navigating PDAC cells through the stromal terrain. Together, our data provides a new role for PSCs in stimulating the metastatic process and underscores the importance of collagen alignment in cancer progression.

  13. Transforming growth factor beta 1 induces CXCL16 and leukemia inhibitory factor expression in osteoclasts to modulate migration of osteoblast progenitors.

    PubMed

    Ota, Kuniaki; Quint, Patrick; Weivoda, Megan M; Ruan, Ming; Pederson, Larry; Westendorf, Jennifer J; Khosla, Sundeep; Oursler, Merry Jo

    2013-11-01

    The processes of bone resorption and bone formation are tightly coupled in young adults, which is crucial to maintenance of bone integrity. We have documented that osteoclasts secrete chemotactic agents to recruit osteoblast lineage cells, contributing to coupling. Bone formation subsequent to bone resorption becomes uncoupled with aging, resulting in significant bone loss. During bone resorption, osteoclasts release and activate transforming growth factor beta 1 (TGF-β1) from the bone matrix; thus, elevated bone resorption increases the level of active TGF-β in the local environment during aging. In this study, we examined the influences of TGF-β1 on the ability of osteoclasts to recruit osteoblasts. TGF-β1 increased osteoclast expression of the chemokine CXCL16 to promote osteoblast migration. TGF-β1 also directly stimulated osteoblast migration; however, this direct response was blocked by conditioned medium from TGF-β1-treated osteoclasts due to the presence of leukemia inhibitory factor (LIF) in the medium. CXCL16 and LIF expression was dependent on TGF-β1 activation of Smad2 and Smad3. These results establish that TGF-β1 induces CXCL16 and LIF production in osteoclasts, which modulate recruitment of osteoblasts to restore the bone lost during the resorptive phase of bone turnover. © 2013. Published by Elsevier Inc. All rights reserved.

  14. Epithelial MUC1 promotes cell migration, reduces apoptosis and affects levels of mucosal modulators during acetylsalicylic acid (aspirin)-induced gastropathy.

    PubMed

    Banerjee, Debashish; Fernandez, Harvey Robert; Patil, Pradeep Bhatu; Premaratne, Pushpa; Quiding-Järbrink, Marianne; Lindén, Sara Katarina

    2015-02-01

    MUC1 is a transmembrane mucin highly expressed in the stomach. Although extensive research has uncovered many of its roles in cancer, knowledge about the functions of MUC1 in normal tissues is limited. In the present study, we showed that acetylsalicylic acid (ASA; aspirin) up-regulated MUC1/Muc1 expression in the gastric mucosa of humans and wild-type (WT) mice. ASA induced mucosal injury in all mice to a similar extent; however, WT animals and those chimaeras with Muc1 on the epithelia recovered faster than Muc1-knockout (KO) mice and chimaeras carrying Muc1 on haemopoietic but not epithelial cells. MUC1 enhanced proliferation and migration of the human gastric cell line MKN-7 and increased resistance to apoptosis. The repeated treatment regime used caused a reduction in cyclo-oxygenase-1 (Cox-1) expression, though WT animals returned faster towards pre-treatment levels and had increased Cox-2 and vascular endothelial growth factor levels during recovery. Thus we found that epithelial Muc1 is more important for the healing process than haemopoietic Muc1 and Muc1/MUC1 facilitates wound healing by enhancing cell migration and proliferation, protecting against apoptosis and mediating expression of mucosal modulators. Thus MUC1 plays essential roles during wound healing and development of treatment modalities targeting enhanced expression of MUC1 may be beneficial to treat mucosal wounds.

  15. Wdpcp, a PCP protein required for ciliogenesis, regulates directional cell migration and cell polarity by direct modulation of the actin cytoskeleton.

    PubMed

    Cui, Cheng; Chatterjee, Bishwanath; Lozito, Thomas P; Zhang, Zhen; Francis, Richard J; Yagi, Hisato; Swanhart, Lisa M; Sanker, Subramaniam; Francis, Deanne; Yu, Qing; San Agustin, Jovenal T; Puligilla, Chandrakala; Chatterjee, Tania; Tansey, Terry; Liu, Xiaoqin; Kelley, Matthew W; Spiliotis, Elias T; Kwiatkowski, Adam V; Tuan, Rocky; Pazour, Gregory J; Hukriede, Neil A; Lo, Cecilia W

    2013-11-01

    Planar cell polarity (PCP) regulates cell alignment required for collective cell movement during embryonic development. This requires PCP/PCP effector proteins, some of which also play essential roles in ciliogenesis, highlighting the long-standing question of the role of the cilium in PCP. Wdpcp, a PCP effector, was recently shown to regulate both ciliogenesis and collective cell movement, but the underlying mechanism is unknown. Here we show Wdpcp can regulate PCP by direct modulation of the actin cytoskeleton. These studies were made possible by recovery of a Wdpcp mutant mouse model. Wdpcp-deficient mice exhibit phenotypes reminiscent of Bardet-Biedl/Meckel-Gruber ciliopathy syndromes, including cardiac outflow tract and cochlea defects associated with PCP perturbation. We observed Wdpcp is localized to the transition zone, and in Wdpcp-deficient cells, Sept2, Nphp1, and Mks1 were lost from the transition zone, indicating Wdpcp is required for recruitment of proteins essential for ciliogenesis. Wdpcp is also found in the cytoplasm, where it is localized in the actin cytoskeleton and in focal adhesions. Wdpcp interacts with Sept2 and is colocalized with Sept2 in actin filaments, but in Wdpcp-deficient cells, Sept2 was lost from the actin cytoskeleton, suggesting Wdpcp is required for Sept2 recruitment to actin filaments. Significantly, organization of the actin filaments and focal contacts were markedly changed in Wdpcp-deficient cells. This was associated with decreased membrane ruffling, failure to establish cell polarity, and loss of directional cell migration. These results suggest the PCP defects in Wdpcp mutants are not caused by loss of cilia, but by direct disruption of the actin cytoskeleton. Consistent with this, Wdpcp mutant cochlea has normal kinocilia and yet exhibits PCP defects. Together, these findings provide the first evidence, to our knowledge, that a PCP component required for ciliogenesis can directly modulate the actin cytoskeleton to

  16. Expression of membrane progesterone receptors (mPRs) in rat peripheral glial cell membranes and their potential role in the modulation of cell migration and protein expression.

    PubMed

    Castelnovo, Luca F; Magnaghi, Valerio; Thomas, Peter

    2017-09-26

    The role played by progestogens in modulating Schwann cell pathophysiology is well established. Progestogens exert their effects in these cells through both classical genomic and non-genomic mechanisms, the latter mediated by the GABA-A receptor. However, there is evidence that other receptors may be involved. Membrane progesterone receptors (mPRs) are novel 7-transmembrane receptors coupled to G proteins that have been characterized in different tissues and cells, including the central nervous system (CNS). The mPRs were shown to mediate some of progestogens' neuroprotective effects in the CNS, and to be upregulated in glial cells after traumatic brain injury. Based on this evidence, this paper investigated the possible involvement of mPRs in mediating progestogen actions in S42 Schwann cells. All five mPR isoforms and progesterone receptor membrane component 1 (PGRMC1) were detected in Schwann cells, and were present on the cell membrane. Progesterone and the mPR-specific agonist, Org-OD-02-0 (02) bound to these membranes, indicating the presence of functional mPRs. The mPR agonist 02 rapidly increased cell migration in an in vitro assay, suggesting a putative role of mPRs in the nerve regeneration process. Treatment with pertussis toxin, and 8-Br-cAMP blocked 02-induced cell migration, suggesting this progestogen action is mediated by activation of an inhibitory G protein leading to a decrease in intracellular cAMP levels. In contrast, long-term mPR activation led to increased expression levels of myelin associated glycoprotein (MAG). Taken together, these findings show that mPRs are present and active in Schwann cells and have a role in modulating their physiological processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Wdpcp, a PCP Protein Required for Ciliogenesis, Regulates Directional Cell Migration and Cell Polarity by Direct Modulation of the Actin Cytoskeleton

    PubMed Central

    Cui, Cheng; Chatterjee, Bishwanath; Lozito, Thomas P.; Zhang, Zhen; Francis, Richard J.; Yagi, Hisato; Swanhart, Lisa M.; Sanker, Subramaniam; Francis, Deanne; Yu, Qing; San Agustin, Jovenal T.; Puligilla, Chandrakala; Chatterjee, Tania; Tansey, Terry; Liu, Xiaoqin; Kelley, Matthew W.; Spiliotis, Elias T.; Kwiatkowski, Adam V.; Tuan, Rocky; Pazour, Gregory J.; Hukriede, Neil A.; Lo, Cecilia W.

    2013-01-01

    Planar cell polarity (PCP) regulates cell alignment required for collective cell movement during embryonic development. This requires PCP/PCP effector proteins, some of which also play essential roles in ciliogenesis, highlighting the long-standing question of the role of the cilium in PCP. Wdpcp, a PCP effector, was recently shown to regulate both ciliogenesis and collective cell movement, but the underlying mechanism is unknown. Here we show Wdpcp can regulate PCP by direct modulation of the actin cytoskeleton. These studies were made possible by recovery of a Wdpcp mutant mouse model. Wdpcp-deficient mice exhibit phenotypes reminiscent of Bardet–Biedl/Meckel–Gruber ciliopathy syndromes, including cardiac outflow tract and cochlea defects associated with PCP perturbation. We observed Wdpcp is localized to the transition zone, and in Wdpcp-deficient cells, Sept2, Nphp1, and Mks1 were lost from the transition zone, indicating Wdpcp is required for recruitment of proteins essential for ciliogenesis. Wdpcp is also found in the cytoplasm, where it is localized in the actin cytoskeleton and in focal adhesions. Wdpcp interacts with Sept2 and is colocalized with Sept2 in actin filaments, but in Wdpcp-deficient cells, Sept2 was lost from the actin cytoskeleton, suggesting Wdpcp is required for Sept2 recruitment to actin filaments. Significantly, organization of the actin filaments and focal contacts were markedly changed in Wdpcp-deficient cells. This was associated with decreased membrane ruffling, failure to establish cell polarity, and loss of directional cell migration. These results suggest the PCP defects in Wdpcp mutants are not caused by loss of cilia, but by direct disruption of the actin cytoskeleton. Consistent with this, Wdpcp mutant cochlea has normal kinocilia and yet exhibits PCP defects. Together, these findings provide the first evidence, to our knowledge, that a PCP component required for ciliogenesis can directly modulate the actin cytoskeleton to

  18. High Expression of LINC01420 indicates an unfavorable prognosis and modulates cell migration and invasion in nasopharyngeal carcinoma

    PubMed Central

    Yang, Liting; Tang, Yanyan; He, Yi; Wang, Yumin; Lian, Yu; Xiong, Fang; Shi, Lei; Zhang, Shanshan; Gong, Zhaojian; Zhou, Yujuan; Liao, Qianjin; Zhou, Ming; Li, Xiaoling; Xiong, Wei; Li, Yong; Li, Guiyuan; Zeng, Zhaoyang; Guo, Can

    2017-01-01

    Recent studies demonstrated that long non-coding RNAs (lncRNAs) deregulated in many cancer tissues including nasopharyngeal carcinoma (NPC) and had critical roles in cancer progression and metastasis. In this study, we aimed to assess a lncRNA LINC01420 expression in NPC and explore its role in NPC pathogenesis. Our research revealed that the expression level of LINC01420 in NPC tissues were higher than nasopharyngeal epithelial (NPE) tissues. Moreover, NPC patients with high LINC01420 expression level showed poor overall survival. Knockdown LINC01420 inhibited NPC cell migration and invasion in vitro. In summary, LINC01420 may play a critical role in NPC progression and may serve as a potential prognostic biomarker in NPC patients. PMID:28123602

  19. Structural Modulation of Brain Development by Oxygen: Evidence on Adolescents Migrating from High Altitude to Sea Level Environment

    PubMed Central

    Zhang, Jiaxing; Zhang, Haiyan; Chen, Ji; Fan, Ming; Gong, Qiyong

    2013-01-01

    The present study aimed to investigate structural modulation of brain by high level of oxygen during its peak period of development. Voxel-based morphometry analysis of gray matter (GM) and white matter (WM) volumes and Tract-Based Spatial Statistics analysis of WM fractional anisotropy (FA) and mean diffusion (MD) based on MRI images were carried out on 21 Tibetan adolencents (15–18 years), who were born and raised in Qinghai-Tibetan Plateau (2900–4700 m) and have lived at sea level (SL) in the last 4 years. The control group consisted of matched Tibetan adolescents born and raised at high altitude all the time. SL immigrants had increased GM volume in the left insula, left inferior parietal gyrus, and right superior parietal gyrus and decreased GM in the left precentral cortex and multiple sites in cerebellar cortex (left lobule 8, bilateral lobule 6 and crus 1/2). Decreased WM volume was found in the right superior frontal gyrus in SL immigrants. SL immigrants had higher FA and lower MD at multiple sites of WM tracts. Moreover, we detected changes in ventilation and circulation. GM volume in cerebellum lobule 8 positively correlated with diastolic pressure, while GM volume in insula positively correlated vital capacity and hypoxic ventilatory response. Our finding indicate that the structural modulations of GM by high level of oxygen during its peak period of development are related to respiratory and circulatory regulations, while the modulation in WM mainly exhibits an enhancement in myelin maturation. PMID:23874449

  20. Hexachlorobenzene modulates the crosstalk between the aryl hydrocarbon receptor and transforming growth factor-β1 signaling, enhancing human breast cancer cell migration and invasion.

    PubMed

    Miret, Noelia; Pontillo, Carolina; Ventura, Clara; Carozzo, Alejandro; Chiappini, Florencia; Kleiman de Pisarev, Diana; Fernández, Natalia; Cocca, Claudia; Randi, Andrea

    2016-07-29

    Given the number of women affected by breast cancer, considerable interest has been raised in understanding the relationships between environmental chemicals and disease onset. Hexachlorobenzene (HCB) is a dioxin-like compound that is widely distributed in the environment and is a weak ligand of the aryl hydrocarbon receptor (AhR). We previously demonstrated that HCB acts as an endocrine disruptor capable of stimulating cell proliferation, migration, invasion, and metastasis in different breast cancer models. In addition, increasing evidence indicates that transforming growth factor-β1 (TGF-β1) can contribute to tumor maintenance and progression. In this context, this work investigated the effect of HCB (0.005, 0.05, 0.5, and 5μM) on TGF-β1 signaling and AhR/TGF-β1 crosstalk in the human breast cancer cell line MDA-MB-231 and analyzed whether TGF-β1 pathways are involved in HCB-induced cell migration and invasion. RT-qPCR results indicated that HCB reduces AhR mRNA expression through TGF-β1 signaling but enhances TGF-β1 mRNA levels involving AhR signaling. Western blot analysis demonstrated that HCB could increase TGF-β1 protein levels and activation, as well as Smad3, JNK, and p38 phosphorylation. In addition, low and high doses of HCB were determined to exert differential effects on AhR protein levels, localization, and activation, with a high dose (5μM) inducing AhR nuclear translocation and AhR-dependent CYP1A1 expression. These findings also revealed that c-Src and AhR are involved in HCB-mediated activation of Smad3. HCB enhances cell migration (scratch motility assay) and invasion (Transwell assay) through the Smad, JNK, and p38 pathways, while ERK1/2 is only involved in HCB-induced cell migration. These results demonstrate that HCB modulates the crosstalk between AhR and TGF-β1 and consequently exacerbates a pro-migratory phenotype in MDA-MB-231 cells, which contributes to a high degree of malignancy. Taken together, our findings help to

  1. Modulation of tumor cell stiffness and migration by type IV collagen through direct activation of integrin signaling pathway.

    PubMed

    Chen, Sheng-Yi; Lin, Jo-Shi; Yang, Bei-Chang

    2014-08-01

    Excessive collagen deposition plays a critical role in tumor progression and metastasis. To understand how type IV collagen affects mechanical stiffness and migration, low-collagen-IV-expressing transfectants of B16F10, U118MG, and Huh7 (denoted shCol cells) were established by the lentiviral-mediated delivery of small interfering RNA against type IV-α1 collagen (Col4A1). Although having similar growth rates, shCol cells showed a flatter morphology compared to that of the corresponding controls. Notably, knocking down the Col4A1 gene conferred the cells with higher levels of elasticity and lower motility. Exposure to blocking antibodies against human β1 integrin or α2β1 integrin or the pharmacological inhibition of Src and ERK activity by PP1 and U0126, respectively, effectively reduced cell motility and raised cell stiffness. Reduced Src and ERK activities in shCol cells indicate the involvement of a collagen IV/integrin signaling pathway. The forced expression of β1 integrin significantly stimulated Src and ERK phosphorylation, reduced cell stiffness, and accelerated cell motility. In an experimental metastasis assay using C57BL/6 mice, B16F10 shCol cells formed significantly fewer and smaller lung nodules, confirming the contribution of collagen to metastasis. In summary, the integrin signaling pathway activated in a tumor environment with collagen deposition is responsible for low cell elasticity and high metastatic ability.

  2. Extracellular Superoxide Dismutase Expression in Papillary Thyroid Cancer Mesenchymal Stem/Stromal Cells Modulates Cancer Cell Growth and Migration

    PubMed Central

    Parascandolo, Alessia; Rappa, Francesca; Cappello, Francesco; Kim, Jaehyup; Cantu, David A.; Chen, Herbert; Mazzoccoli, Gianluigi; Hematti, Peiman; Castellone, Maria Domenica; Salvatore, Marco; Laukkanen, Mikko O.

    2017-01-01

    Tumor stroma-secreted growth factors, cytokines, and reactive oxygen species (ROS) influence tumor development from early stages to the metastasis phase. Previous studies have demonstrated downregulation of ROS-producing extracellular superoxide dismutase (SOD3) in thyroid cancer cell lines although according to recent data, the expression of SOD3 at physiological levels stimulates normal and cancer cell proliferation. Therefore, to analyze the expression of SOD3 in tumor stroma, we characterized stromal cells from the thyroid. We report mutually exclusive desmoplasia and inflammation in papillary and follicular thyroid cancers and the presence of multipotent mesenchymal stem/stromal cells (MSCs) in non-carcinogenic thyroids and papillary thyroid cancer (PTC). The phenotypic and differentiation characteristics of Thyroid MSCs and PTC MSCs were comparable with bone marrow MSCs. A molecular level analysis showed increased FIBROBLAST ACTIVATING PROTEIN, COLLAGEN 1 TYPE A1, TENASCIN, and SOD3 expression in PTC MSCs compared to Thyroid MSCs, suggesting the presence of MSCs with a fibrotic fingerprint in papillary thyroid cancer tumors and the autocrine-paracrine conversion of SOD3 expression, which was enhanced by cancer cells. Stromal SOD3 had a stimulatory effect on cancer cell growth and an inhibitory effect on cancer cell migration, thus indicating that SOD3 might be a novel player in thyroid tumor stroma. PMID:28216675

  3. The mitogen-inducible Fn14 gene encodes a type I transmembrane protein that modulates fibroblast adhesion and migration.

    PubMed

    Meighan-Mantha, R L; Hsu, D K; Guo, Y; Brown, S A; Feng, S L; Peifley, K A; Alberts, G F; Copeland, N G; Gilbert, D J; Jenkins, N A; Richards, C M; Winkles, J A

    1999-11-12

    The binding of polypeptide growth factors to their appropriate cell surface transmembrane receptors triggers numerous biochemical responses, including the transcriptional activation of specific genes. We have used a differential display approach to identify fibroblast growth factor-1-inducible genes in murine NIH 3T3 cells. Here, we report that the fibroblast growth factor-inducible-14 (Fn14) gene is a growth factor-regulated, immediate-early response gene expressed in a developmental stage- and adult tissue-specific manner in vivo. This gene, located on mouse chromosome 17, is predicted to encode an 129-amino acid type Ia membrane protein with no significant sequence similarity to any known protein. We have used two experimental approaches, direct fluorescence microscopy and immunoprecipitation analysis of biotinylated cell surface proteins, to demonstrate that Fn14 is located on the plasma membrane. To examine the biological consequences of constitutive Fn14 expression, we isolated NIH 3T3 cell lines expressing variable levels of epitope-tagged Fn14 and analyzed their phenotypic properties in vitro. These experiments revealed that Fn14 expression decreased cellular adhesion to the extracellular matrix proteins fibronectin and vitronectin and also reduced serum-stimulated cell growth and migration. These results indicate that Fn14 is a novel plasma membrane-spanning molecule that may play a role in cell-matrix interactions.

  4. Identification of VLDLR as a novel endothelial cell receptor for fibrin that modulates fibrin-dependent transendothelial migration of leukocytes.

    PubMed

    Yakovlev, Sergiy; Mikhailenko, Irina; Cao, Chunzhang; Zhang, Li; Strickland, Dudley K; Medved, Leonid

    2012-01-12

    While testing the effect of the (β15-66)(2) fragment, which mimics a pair of fibrin βN-domains, on the morphology of endothelial cells, we found that this fragment induces redistribution of vascular endothelial-cadherin in a process that is inhibited by the receptor-associated protein (RAP). Based on this finding, we hypothesized that fibrin may interact with members of RAP-dependent low-density lipoprotein (LDL) receptor family. To test this hypothesis, we examined the interaction of (β15-66)(2), fibrin, and several fibrin-derived fragments with 2 members of this family by ELISA and surface plasmon resonance. The experiments showed that very LDL (VLDL) receptor (VLDLR) interacts with high affinity with fibrin through its βN-domains, and this interaction is inhibited by RAP and (β15-66)(2). Furthermore, RAP inhibited transendothelial migration of neutrophils induced by fibrin-derived NDSK-II fragment containing βN-domains, suggesting the involvement of VLDLR in fibrin-dependent leukocyte transmigration. Our experiments with VLDLR-deficient mice confirmed this suggestion by showing that, in contrast to wild-type mice, fibrin-dependent leukocyte transmigration does not occur in such mice. Altogether, the present study identified VLDLR as a novel endothelial cell receptor for fibrin that promotes fibrin-dependent leukocyte transmigration and thereby inflammation. Establishing the molecular mechanism underlying this interaction may result in the development of novel inhibitors of fibrin-dependent inflammation.

  5. Vitamin D Modulates Hematological Parameters and Cell Migration into Peritoneal and Pulmonary Cavities in Alloxan-Diabetic Mice

    PubMed Central

    Bella, Leonardo M.; Fieri, Isis; Nunes, Fernanda P. B.; Ferreira, Sabrina S.; Azevedo, Carolina B.

    2017-01-01

    Background/Aims. The effects of cholecalciferol supplementation on the course of diabetes in humans and animals need to be better understood. Therefore, this study investigated the effect of short-term cholecalciferol supplementation on biochemical and hematological parameters in mice. Methods. Male diabetic (alloxan, 60 mg/kg i.v., 10 days) and nondiabetic mice were supplemented with cholecalciferol for seven days. The following parameters were determined: serum levels of 25-hydroxyvitamin D, phosphorus, calcium, urea, creatinine, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, red blood cell count, white blood cell count (WBC), hematocrit, hemoglobin, differential cell counts of peritoneal lavage (PeL), and bronchoalveolar lavage (BAL) fluids and morphological analysis of lung, kidney, and liver tissues. Results. Relative to controls, cholecalciferol supplementation increased serum levels of 25-hydroxyvitamin D, calcium, hemoglobin, hematocrit, and red blood cell counts and decreased leukocyte cell counts of PeL and BAL fluids in diabetic mice. Diabetic mice that were not treated with cholecalciferol had lower serum calcium and albumin levels and hemoglobin, WBC, and mononuclear blood cell counts and higher serum creatinine and urea levels than controls. Conclusion. Our results suggest that cholecalciferol supplementation improves the hematological parameters and reduces leukocyte migration into the PeL and BAL lavage of diabetic mice. PMID:28503574

  6. Unsaturated Fatty Acids Drive Disintegrin and Metalloproteinase (ADAM)-dependent Cell Adhesion, Proliferation, and Migration by Modulating Membrane Fluidity*

    PubMed Central

    Reiss, Karina; Cornelsen, Isabell; Husmann, Matthias; Gimpl, Gerald; Bhakdi, Sucharit

    2011-01-01

    The disintegrin-metalloproteinases ADAM10 and ADAM17 mediate the release of several cell signaling molecules and cell adhesion molecules such as vascular endothelial cadherin or L-selectin affecting endothelial permeability and leukocyte transmigration. Dysregulation of ADAM activity may contribute to the pathogenesis of vascular diseases, but the mechanisms underlying the control of ADAM functions are still incompletely understood. Atherosclerosis is characterized by lipid plaque formation and local accumulation of unsaturated free fatty acids (FFA). Here, we show that unsaturated FFA increase ADAM-mediated substrate cleavage. We demonstrate that these alterations are not due to genuine changes in enzyme activity, but correlate with changes in membrane fluidity as revealed by measurement of 1,6-diphenyl-1,3,5-hexatriene fluorescence anisotropy and fluorescence recovery after photobleaching analyses. ELISA and immunoblot experiments conducted with granulocytes, endothelial cells, and keratinocytes revealed rapid increase of ectodomain shedding of ADAM10 and ADAM17 substrates upon membrane fluidization. Large amounts of unsaturated FFA may be liberated from cholesteryl esters in LDL that is entrapped in atherosclerotic lesions. Incubation of cells with thus modified LDL resulted in rapid cleavage of ADAM substrates with corresponding functional consequences on cell proliferation, cell migration, and endothelial permeability, events of high significance in atherogenesis. We propose that FFA represent critical regulators of ADAM function that may assume relevance in many biological settings through their influence on mobility of enzyme and substrate in lipid bilayers. PMID:21642425

  7. Unsaturated fatty acids drive disintegrin and metalloproteinase (ADAM)-dependent cell adhesion, proliferation, and migration by modulating membrane fluidity.

    PubMed

    Reiss, Karina; Cornelsen, Isabell; Husmann, Matthias; Gimpl, Gerald; Bhakdi, Sucharit

    2011-07-29

    The disintegrin-metalloproteinases ADAM10 and ADAM17 mediate the release of several cell signaling molecules and cell adhesion molecules such as vascular endothelial cadherin or L-selectin affecting endothelial permeability and leukocyte transmigration. Dysregulation of ADAM activity may contribute to the pathogenesis of vascular diseases, but the mechanisms underlying the control of ADAM functions are still incompletely understood. Atherosclerosis is characterized by lipid plaque formation and local accumulation of unsaturated free fatty acids (FFA). Here, we show that unsaturated FFA increase ADAM-mediated substrate cleavage. We demonstrate that these alterations are not due to genuine changes in enzyme activity, but correlate with changes in membrane fluidity as revealed by measurement of 1,6-diphenyl-1,3,5-hexatriene fluorescence anisotropy and fluorescence recovery after photobleaching analyses. ELISA and immunoblot experiments conducted with granulocytes, endothelial cells, and keratinocytes revealed rapid increase of ectodomain shedding of ADAM10 and ADAM17 substrates upon membrane fluidization. Large amounts of unsaturated FFA may be liberated from cholesteryl esters in LDL that is entrapped in atherosclerotic lesions. Incubation of cells with thus modified LDL resulted in rapid cleavage of ADAM substrates with corresponding functional consequences on cell proliferation, cell migration, and endothelial permeability, events of high significance in atherogenesis. We propose that FFA represent critical regulators of ADAM function that may assume relevance in many biological settings through their influence on mobility of enzyme and substrate in lipid bilayers.

  8. Three-dimensional matrix fiber alignment modulates cell migration and MT1-MMP utility by spatially and temporally directing protrusions.

    PubMed

    Fraley, Stephanie I; Wu, Pei-Hsun; He, Lijuan; Feng, Yunfeng; Krisnamurthy, Ranjini; Longmore, Gregory D; Wirtz, Denis

    2015-10-01

    Multiple attributes of the three-dimensional (3D) extracellular matrix (ECM) have been independently implicated as regulators of cell motility, including pore size, crosslink density, structural organization, and stiffness. However, these parameters cannot be independently varied within a complex 3D ECM protein network. We present an integrated, quantitative study of these parameters across a broad range of complex matrix configurations using self-assembling 3D collagen and show how each parameter relates to the others and to cell motility. Increasing collagen density resulted in a decrease and then an increase in both pore size and fiber alignment, which both correlated significantly with cell motility but not bulk matrix stiffness within the range tested. However, using the crosslinking enzyme Transglutaminase II to alter microstructure independently of density revealed that motility is most significantly predicted by fiber alignment. Cellular protrusion rate, protrusion orientation, speed of migration, and invasion distance showed coupled biphasic responses to increasing collagen density not predicted by 2D models or by stiffness, but instead by fiber alignment. The requirement of matrix metalloproteinase (MMP) activity was also observed to depend on microstructure, and a threshold of MMP utility was identified. Our results suggest that fiber topography guides protrusions and thereby MMP activity and motility.

  9. Impairment of CCR6+ and CXCR3+ Th Cell Migration in HIV-1 Infection Is Rescued by Modulating Actin Polymerization

    PubMed Central

    Bernasconi, Enos; Speck, Roberto F.; Proietti, Michele; Sauermann, Ulrike; D’Agostino, Gianluca; Danelon, Gabriela; Rezzonico Jost, Tanja; Grassi, Fabio; Raeli, Lorenzo; Schöni-Affolter, Franziska; Stahl-Hennig, Christiane

    2017-01-01

    CD4+ T cell repopulation of the gut is rarely achieved in HIV-1–infected individuals who are receiving clinically effective antiretroviral therapy. Alterations in the integrity of the mucosal barrier have been indicated as a cause for chronic immune activation and disease progression. In this study, we present evidence that persistent immune activation causes impairment of lymphocytes to respond to chemotactic stimuli, thus preventing their trafficking from the blood stream to peripheral organs. CCR6+ and CXCR3+ Th cells accumulate in the blood of aviremic HIV-1–infected patients on long-term antiretroviral therapy, and their frequency in the circulation positively correlates to levels of soluble CD14 in plasma, a marker of chronic immune activation. Th cells show an impaired response to chemotactic stimuli both in humans and in the pathogenic model of SIV infection, and this defect is due to hyperactivation of cofilin and inefficient actin polymerization. Taking advantage of a murine model of chronic immune activation, we demonstrate that cytoskeleton remodeling, induced by okadaic acid, restores lymphocyte migration in response to chemokines, both in vitro and in vivo. This study calls for novel pharmacological approaches in those pathological conditions characterized by persistent immune activation and loss of trafficking of T cell subsets to niches that sustain their maturation and activities. PMID:27895171

  10. Interplay between PCBP2 and miRNA modulates ARHGDIA expression and function in glioma migration and invasion

    PubMed Central

    Lin, Xihua; Yang, Bin; Liu, Wei; Tan, Xiaochao; Wu, Fan; Hu, Peishan; Jiang, Tao; Bao, Zhaoshi; Yuan, Jiangang; Qiang, Boqin; Peng, Xiaozhong; Han, Wei

    2016-01-01

    RNA-RNA and protein-RNA interactions are essential for post-transcriptional regulationin normal development and may be deregulated in cancer initiation and progression. The RNA-binding protein PCBP2, an oncogenic protein in human malignant gliomas, is an essential regulator of mRNA and miRNA biogenesis, stability and activity. Here, we identified Rho GDP dissociation inhibitor α (ARHGDIA) as a target mRNA that binds to PCBP2, and we uncovered the role of ARHGDIA as a putative metastasis suppressor through analyses of in vitro and in vivo models of EMT and metastasis. Furthermore, we demonstrated that ARHGDIA is a potential target of miR-151-5p and miR-16 in gliomas. The interaction between PCBP2 and the 3′UTR of the ARHGDIA mRNA may induce a local change in RNA structure that favors subsequent binding of miR-151-5p and miR-16, thus leading to the suppression of ARHGDIA expression. PCBP2 may facilitate miR-151-5p and miR-16 promotion of glioma cell migration and invasion through mitigating the function of ARHGDIA. PMID:26761212

  11. EOS7CA Version 1.0: TOUGH2 Module for Gas Migration in Shallow Subsurface Porous Media Systems

    SciTech Connect

    Oldenburg, Curtis M.

    2015-03-06

    EOS7CA is a TOUGH2 module for mixtures of a non-condensible gas (NCG) and air with or without a gas tracer, an aqueous phase, and water vapor. The user can select the NCG as being CO2, N2, or CH4. EOS7CA uses a cubic equation of state with a multiphase version of Darcy’s Law to model flow and transport of gas and aqueous phase mixtures over a range of pressures and temperatures appropriate to shallow subsurface porous media systems. The limitation to shallow systems arises from the use of Henry’s Law for gas solubility which is appropriate for low pressures but begins to over-predict solubility starting at pressures greater than approximately 1 MPa (10 bar). The components modeled in EOS7CA are water, brine, NCG, gas tracer, air, and optional heat. The real gas properties module (ZEVCA) has options for Peng-Robinson, Redlich-Kwong, or Soave-Redlich-Kwong equations of state to calculate gas mixture density, enthalpy departure, and viscosity. Transport of the gaseous and dissolved components is by advection and Fickian molecular diffusion. This user guide provides instructions for use and two sample problems as verification and demonstration of EOS7CA.

  12. EOS7CA Version 1.0: TOUGH2 Module for Gas Migration in Shallow Subsurface Porous Media Systems

    SciTech Connect

    Oldenburg, Curtis M.

    2015-06-22

    EOS7CA is a TOUGH2 module for mixtures of a non-condensible gas (NCG) and air (with or without a gas tracer), an aqueous phase, and water vapor. The user can select the NCG as being CO2, N2, or CH4. EOS7CA uses a cubic equation of state with a multiphase version of Darcy’s Law to model flow and transport of gas and aqueous phase mixtures over a range of pressures and temperatures appropriate to shallow subsurface porous media systems. The limitation to shallow systems arises from the use of Henry’s Law for gas solubility which is appropriate for low pressures but begins to over-predict solubility starting at pressures greater than approximately 1 MPa (10 bar). The components modeled in EOS7CA are water, brine, NCG, gas tracer, air, and optional heat.

  13. Systemic Neutrophil Depletion Modulates the Migration and Fate of Transplanted Human Neural Stem Cells to Rescue Functional Repair.

    PubMed

    Nguyen, Hal X; Hooshmand, Mitra J; Saiwai, Hirokazu; Maddox, Jake; Salehi, Arjang; Lakatos, Anita; Nishi, Rebecca A; Salazar, Desiree; Uchida, Nobuko; Anderson, Aileen J

    2017-09-20

    The interaction of transplanted stem cells with local cellular and molecular cues in the host CNS microenvironment may affect the potential for repair by therapeutic cell populations. In this regard, spinal cord injury (SCI), Alzheimer's disease, and other neurological injuries and diseases all exhibit dramatic and dynamic changes to the host microenvironment over time. Previously, we reported that delayed transplantation of human CNS-derived neural stem cells (hCNS-SCns) at 9 or 30 d post-SCI (dpi) resulted in extensive donor cell migration, predominantly neuronal and oligodendrocytic donor cell differentiation, and functional locomotor improvements. Here, we report that acute transplantation of hCNS-SCns at 0 dpi resulted in localized astroglial differentiation of donor cells near the lesion epicenter and failure to produce functional improvement in an all-female immunodeficient mouse model. Critically, specific immunodepletion of neutrophils (polymorphonuclear leukocytes) blocked hCNS-SCns astroglial differentiation near the lesion epicenter and rescued the capacity of these cells to restore function. These data represent novel evidence that a host immune cell population can block the potential for functional repair derived from a therapeutic donor cell population, and support targeting the inflammatory microenvironment in combination with cell transplantation after SCI.SIGNIFICANCE STATEMENT The interaction of transplanted cells with local cellular and molecular cues in the host microenvironment is a key variable that may shape the translation of neurotransplantation research to the clinical spinal cord injury (SCI) human population, and few studies have investigated these events. We show that the specific immunodepletion of polymorphonuclear leukocyte neutrophils using anti-Ly6G inhibits donor cell astrogliosis and rescues the capacity of a donor cell population to promote locomotor improvement after SCI. Critically, our data demonstrate novel evidence that a

  14. Antioxidative Dietary Compounds Modulate Gene Expression Associated with Apoptosis, DNA Repair, Inhibition of Cell Proliferation and Migration

    PubMed Central

    Wang, Likui; Gao, Shijuan; Jiang, Wei; Luo, Cheng; Xu, Maonian; Bohlin, Lars; Rosendahl, Markus; Huang, Wenlin

    2014-01-01

    Many dietary compounds are known to have health benefits owing to their antioxidative and anti-inflammatory properties. To determine the molecular mechanism of these food-derived compounds, we analyzed their effect on various genes related to cell apoptosis, DNA damage and repair, oxidation and inflammation using in vitro cell culture assays. This review further tests the hypothesis proposed previously that downstream products of COX-2 (cyclooxygenase-2) called electrophilic oxo-derivatives induce antioxidant responsive elements (ARE), which leads to cell proliferation under antioxidative conditions. Our findings support this hypothesis and show that cell proliferation was inhibited when COX-2 was down-regulated by polyphenols and polysaccharides. Flattened macrophage morphology was also observed following the induction of cytokine production by polysaccharides extracted from viili, a traditional Nordic fermented dairy product. Coix lacryma-jobi (coix) polysaccharides were found to reduce mitochondrial membrane potential and induce caspase-3- and 9-mediated apoptosis. In contrast, polyphenols from blueberries were involved in the ultraviolet-activated p53/Gadd45/MDM2 DNA repair system by restoring the cell membrane potential. Inhibition of hypoxia-inducible factor-1 by saponin extracts of ginsenoside (Ginsen) and Gynostemma and inhibition of S100A4 by coix polysaccharides inhibited cancer cell migration and invasion. These observations suggest that antioxidants and changes in cell membrane potential are the major driving forces that transfer signals through the cell membrane into the cytosol and nucleus, triggering gene expression, changes in cell proliferation and the induction of apoptosis or DNA repair. PMID:25226533

  15. Vascular Endothelial Growth Factor (VEGF) and Platelet (PF-4) Factor 4 Inputs Modulate Human Microvascular Endothelial Signaling in a Three-Dimensional Matrix Migration Context*

    PubMed Central

    Hang, Ta-Chun; Tedford, Nathan C.; Reddy, Raven J.; Rimchala, Tharathorn; Wells, Alan; White, Forest M.; Kamm, Roger D.; Lauffenburger, Douglas A.

    2013-01-01

    The process of angiogenesis is under complex regulation in adult organisms, particularly as it often occurs in an inflammatory post-wound environment. As such, there are many impacting factors that will regulate the generation of new blood vessels which include not only pro-angiogenic growth factors such as vascular endothelial growth factor, but also angiostatic factors. During initial postwound hemostasis, a large initial bolus of platelet factor 4 is released into localized areas of damage before progression of wound healing toward tissue homeostasis. Because of its early presence and high concentration, the angiostatic chemokine platelet factor 4, which can induce endothelial anoikis, can strongly affect angiogenesis. In our work, we explored signaling crosstalk interactions between vascular endothelial growth factor and platelet factor 4 using phosphotyrosine-enriched mass spectrometry methods on human dermal microvascular endothelial cells cultured under conditions facilitating migratory sprouting into collagen gel matrices. We developed new methods to enable mass spectrometry-based phosphorylation analysis of primary cells cultured on collagen gels, and quantified signaling pathways over the first 48 h of treatment with vascular endothelial growth factor in the presence or absence of platelet factor 4. By observing early and late signaling dynamics in tandem with correlation network modeling, we found that platelet factor 4 has significant crosstalk with vascular endothelial growth factor by modulating cell migration and polarization pathways, centered around P38α MAPK, Src family kinases Fyn and Lyn, along with FAK. Interestingly, we found EphA2 correlational topology to strongly involve key migration-related signaling nodes after introduction of platelet factor 4, indicating an influence of the angiostatic factor on this ambiguous but generally angiogenic signal in this complex environment. PMID:24023389

  16. Modulating of ocular inflammation with macrophage migration inhibitory factor is associated with notch signalling in experimental autoimmune uveitis.

    PubMed

    Yang, H; Zheng, S; Mao, Y; Chen, Z; Zheng, C; Li, H; Sumners, C; Li, Q; Yang, P; Lei, B

    2016-02-01

    The aim of this study was to examine whether macrophage migration inhibitory factor (MIF) could exaggerate inflammatory response in a mouse model of experimental autoimmune uveitis (EAU) and to explore the underlying mechanism. Mutant serotype 8 adeno-associated virus (AAV8) (Y733F)-chicken β-actin (CBA)-MIF or AAV8 (Y733F)-CBA-enhanced green fluorescent protein (eGFP) vector was delivered subretinally into B10.RIII mice, respectively. Three weeks after vector delivery, EAU was induced with a subcutaneous injection of a mixture of interphotoreceptor retinoid binding protein (IRBP) peptide with CFA. The levels of proinflammatory cytokines were detected by real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). Retinal function was evaluated with electroretinography (ERG). We found that the expression of MIF and its two receptors CD74 and CD44 was increased in the EAU mouse retina. Compared to AAV8.CBA.eGFP-injected and untreated EAU mice, the level of proinflammatory cytokines, the expression of Notch1, Notch4, delta-like ligand 4 (Dll4), Notch receptor intracellular domain (NICD) and hairy enhancer of split-1 (Hes-1) increased, but the ERG a- and b-wave amplitudes decreased in AAV8.CBA.MIF-injected EAU mice. The Notch inhibitor N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT) reduced the expression of NICD, Hes-1 and proinflammatory cytokines. Further, a MIF antagonist ISO-1 attenuated intraocular inflammation, and inhibited the differentiation of T helper type 1 (Th1) and Th17 in EAU mice. We demonstrated that over-expression of MIF exaggerated ocular inflammation, which was associated with the activation of the Notch signalling. The expression of both MIF and its receptors are elevated in EAU mice. Over-expression of MIF exaggerates ocular inflammation, and this exaggerated inflammation is associated with the activation of the Notch signalling and Notch pathway. Our data suggest that the MIF-Notch axis

  17. Small molecular modulation of macrophage migration inhibitory factor in the hyperoxia-induced mouse model of bronchopulmonary dysplasia

    PubMed Central

    2013-01-01

    Background The role and mechanism of action of MIF in bronchopulmonary dysplasia (BPD) are not known. We hypothesized that increased MIF signaling would ameliorate the pulmonary phenotype of BPD in the mouse lung. Methods We studied newborn wild type (WT), MIF knockout (MIFKO), and lung MIF transgenic (MIFTG) mice in room air and a BPD model, and examined the effects of administering a small molecule MIF agonist and antagonist. Lung morphometry was performed and mRNA and protein expression of vascular mediators were analyzed. Results The pulmonary phenotype of MIFKO and MIFTG mice lungs in room air (RA) and BPD model were comparable to the WT-BPD mice at postnatal (PN) day 14. Vascular endothelial growth factor (VEGF)-A, -R1 and Angiopoietin (Ang)1 mRNA were decreased, and Ang2 increased in the WT-BPD, MIFKO-RA, MIFKO-BPD, MIFTG-RA and MIFTG-BPD mice lungs, compared to appropriate controls. The protein expression of Ang1 in the MIFKO-RA was similar to WT-RA, but decreased in MIFTG-RA, and decreased in all the BPD groups. Ang2 was increased in MIFKO-RA, MIFTG-RA and in all 3 BPD groups. Tie2 was increased in WT-BPD compared to WT-RA, but decreased in MIFKO- and MIFTG- RA and BPD groups. VEGFR1 was uniformly decreased in MIFKO-RA, MIFTG-RA and in all 3 BPD groups. VEGF-A had a similar expression across all RA and BPD groups. There was partial recovery of the pulmonary phenotype in the WT-BPD model treated with the MIF agonist, and in the MIFTG mice treated with the MIF antagonist. Conclusions These data point to the careful regulatory balance exerted by MIF in the developing lung and response to hyperoxia and support the potential therapeutic value of small molecule MIF modulation in BPD. PMID:23448134

  18. CD97 inhibits cell migration in human fibrosarcoma cells by modulating TIMP-2/MT1- MMP/MMP-2 activity--role of GPS autoproteolysis and functional cooperation between the N- and C-terminal fragments.

    PubMed

    Hsiao, Cheng-Chih; Wang, Wen-Chih; Kuo, Wan-Lin; Chen, Hsin-Yi; Chen, Tse-Ching; Hamann, Jörg; Lin, Hsi-Hsien

    2014-11-01

    CD97 is a tumor-associated adhesion-class G-protein-coupled receptor involved in modulating cell migration. Adhesion-class G-protein-coupled receptors are characterized by proteolytic cleavage at a G-protein-coupled receptor proteolysis site (GPS) into an N-terminal fragment (NTF) and a C-terminal fragment (CTF), which remain associated noncovalently. The molecular mechanism and the role of GPS proteolysis in CD97-modulated cell migration are not completely understood. We report here that CD97 expression in HT1080 fibrosarcoma cells enhanced tissue inhibitor of metalloproteinase-2 secretion, leading to reduced membrane type 1 matrix metalloproteinase and matrix metalloproteinase 2 activities. This, in turn, impaired cell migration and invasion in vitro and lung macrometastasis in vivo. CD97 expression also upregulated the expression of integrins, promoting cell adhesion. Importantly, these cellular functions absolutely required the presence of both the NTF and the CTF of CD97, confirming functional cooperation between the two receptor subunits. CD97 gene knockdown reversed these phenotypic changes. We conclude that GPS proteolysis and the functional interplay between the NTF and the CTF are indispensible for CD97 to inhibit HT1080 cell migration by suppressing matrix metalloproteinase activity. © 2014 FEBS.

  19. Tetraspanins in Cell Migration

    PubMed Central

    Jiang, Xupin; Zhang, Jiaping; Huang, Yuesheng

    2015-01-01

    Tetraspanins are a superfamily of small transmembrane proteins that are expressed in almost all eukaryotic cells. Through interacting with one another and with other membrane and intracellular proteins, tetraspanins regulate a wide range of proteins such as integrins, cell surface receptors, and signaling molecules, and thereby engage in diverse cellular processes ranging from cell adhesion and migration to proliferation and differentiation. In particular, tetraspanins modulate the function of proteins involved in all determining factors of cell migration including cell–cell adhesion, cell–ECM adhesion, cytoskeletal protrusion/contraction, and proteolytic ECM remodeling. We herein provide a brief overview of collective in vitro and in vivo studies of tetraspanins to illustrate their regulatory functions in the migration and trafficking of cancer cells, vascular endothelial cells, skin cells (keratinocytes and fibroblasts), and leukocytes. We also discuss the involvement of tetraspanins in various pathologic and remedial processes that rely on cell migration and their potential value as targets for therapeutic intervention. PMID:26091149

  20. Extracellular matrix (ECM) modulates the EGF-induced migration of liver epithelial cells in serum-free, hormone-supplemented medium.

    PubMed

    Bade, E G; Nitzgen, B

    1985-04-01

    The influence of the extracellular matrix (ECM) glycoproteins collagen IV, laminin (LN), and fibronectin (FN) on the in vitro migration of epithelial cells was studied using the ECM migration track method (4) with preparations immunostained for LN and FN. The locomotion of rat liver epithelial cells stimulated to migrate in serum-free medium by epidermal growth factor (EGF) in the presence of insulin is inhibited by substratum-bound FN. The inhibition is concentration-dependent up to 0.7 microgram of the protein per cm2. Neither LN nor collagen IV decreased the number of migrating cells, indicating that the inhibition is a specific effect of fibronectin. The data also indicate that the FN-mediated inhibition of migration is an additional and not alternative mechanism to the well-established contact inhibition of locomotion (1) which also occurs in liver epithelial cell cultures. The system is being used for a further analysis of the factors that influence migration of normal and neoplastic epithelial cells and the biochemical mechanisms underlying the migration reaction.

  1. Non-Selective Cannabinoid Receptor Antagonists, Hinokiresinols Reduce Infiltration of Microglia/Macrophages into Ischemic Brain Lesions in Rat via Modulating 2-Arachidonolyglycerol-Induced Migration and Mitochondrial Activity

    PubMed Central

    Anthony Jalin, Angela M. A.; Rajasekaran, Maheswari; Prather, Paul L.; Kwon, Jin Sun; Gajulapati, Veeraswamy; Choi, Yongseok; Kim, Chunsook; Pahk, Kisoo; Ju, Chung; Kim, Won-Ki

    2015-01-01

    Growing evidence suggests that therapeutic strategies to modulate the post-ischemic inflammatory responses are promising approaches to improve stroke outcome. Although the endocannabinoid system has been emerged as an endogenous therapeutic target to regulate inflammation after stroke insult, the downstream mechanisms and their potentials for therapeutic intervention remain controversial. Here we identified trans- and cis-hinokiresinols as novel non-selective antagonists for two G-protein-coupled cannabinoid receptors, cannabinoid receptor type 1 and type 2. The Electric Cell-substrate Impedance Sensing and Boyden chamber migration assays using primary microglial cultures revealed that both hinokiresinols significantly inhibited an endocannabinoid, 2-arachidonoylglycerol-induced migration. Hinokiresinols modulated 2-arachidonoylglycerol-induced mitochondrial bioenergetics in microglia as evidenced by inhibition of ATP turnover and reduction in respiratory capacity, thereby resulting in impaired migration activity. In rats subjected to transient middle cerebral artery occlusion (1.5-h) followed by 24-h reperfusion, post-ischemic treatment with hinokiresinols (2 and 7-h after the onset of ischemia, 10 mg/kg) significantly reduced cerebral infarct and infiltration of ED1-positive microglial/macrophage cells into cerebral ischemic lesions in vivo. Co-administration of exogenous 2-AG (1 mg/kg, i.v., single dose at 2 h after starting MCAO) abolished the protective effect of trans-hinokiresionol. These results suggest that hinokiresinols may serve as stroke treatment by targeting the endocannabinoid system. Alteration of mitochondrial bioenergetics and consequent inhibition of inflammatory cells migration may be a novel mechanism underlying anti-ischemic effects conferred by cannabinoid receptor antagonists. PMID:26517721

  2. Cell Migration

    PubMed Central

    Trepat, Xavier; Chen, Zaozao; Jacobson, Ken

    2015-01-01

    Cell migration is fundamental to establishing and maintaining the proper organization of multicellular organisms. Morphogenesis can be viewed as a consequence, in part, of cell locomotion, from large-scale migrations of epithelial sheets during gastrulation, to the movement of individual cells during development of the nervous system. In an adult organism, cell migration is essential for proper immune response, wound repair, and tissue homeostasis, while aberrant cell migration is found in various pathologies. Indeed, as our knowledge of migration increases, we can look forward to, for example, abating the spread of highly malignant cancer cells, retarding the invasion of white cells in the inflammatory process, or enhancing the healing of wounds. This article is organized in two main sections. The first section is devoted to the single-cell migrating in isolation such as occurs when leukocytes migrate during the immune response or when fibroblasts squeeze through connective tissue. The second section is devoted to cells collectively migrating as part of multicellular clusters or sheets. This second type of migration is prevalent in development, wound healing, and in some forms of cancer metastasis. PMID:23720251

  3. Neutrophil migration across cultured intestinal epithelial monolayers is modulated by epithelial exposure to IFN-gamma in a highly polarized fashion

    PubMed Central

    1993-01-01

    Neutrophil, or polymorphonuclear leukocyte (PMN), migration across intestinal epithelial barriers, such as occurs in many disease states, appears to result in modifications of epithelial barrier and ion transport functions (Nash, S., J. Stafford, and J. L. Madara. 1987. J. Clin. Invest. 80:1104-1113; Madara, J. L., C. A. Parkos, S. P. Colgan, R. J. MacLeod, S. Nash, J. B. Matthews, C. Delp, and W. I. Lencer. 1992. J. Clin. Invest. 89:1938-1944). Here we investigate the effects of epithelial exposure to IFN-gamma on PMN migration across cultured monolayers of the human intestinal epithelial cell line T84. Transepithelial migration of PMN was initially assessed in the apical- to-basolateral direction, since previous studies indicate general qualitative similarities between PMN migration in the apical-to- basolateral and in the basolateral-to-apical directions. In the apical- to-basolateral direction, epithelial exposure to IFN-gamma markedly upregulated transepithelial migration of PMN in a dose- and time- dependent fashion as measured by both electrical and myeloperoxidase assays. This IFN-gamma-elicited effect on transmigration was specifically due to a IFN-gamma effect on epithelial cells and was not secondary to IFN-gamma effects on epithelial tight junction permeability. Moreover, this IFN-gamma effect was dependent on epithelial protein synthesis, and involved a pathway in which CD11b/18, but not ICAM-1 or CD11a/18, appeared to play a crucial role in PMN- epithelial adhesion. IFN-gamma also substantially modified PMN transepithelial migration in the natural, basolateral-to-apical direction. The IFN-gamma effect on naturally directed transmigration was also specifically due to an IFN-gamma effect on epithelial cells, showed comparable time and dose dependency to that of oppositely directed migration, was CD11b/18 dependent, and required epithelial protein synthesis. Additionally, however, important qualitative differences existed in how IFN-gamma affected

  4. Intermediate-conductance Calcium-activated Potassium Channel KCa3.1 and Chloride Channel Modulate Chemokine Ligand (CCL19/CCL21)-induced Migration of Dendritic Cells

    PubMed Central

    Shao, Zhifei; Gaurav, Rohit; Agrawal, Devendra K

    2014-01-01

    The role of ion channels is largely unknown in chemokine-induced migration in non-excitable cells such as dendritic cells. Here, we examined the role of KCa3.1 and chloride channels in lymphatic chemokines-induced migration of dendritic cells. The amplitude and kinetics of CCL19/21-induced Ca2+ influx were associated with CCR7 expression levels, extracellular free Ca2+ and Cl−, and independent of extracellular K+. Chemokines, CCL19 and CCL21, and KCa3.1 activator, 1-EBIO, induced plasma membrane hyperpolarization and K+ efflux, which was blocked by TRAM-34, suggesting that KCa3.1 carried larger conductance than the inward CRAC. Blockade of KCa3.1, low Cl− in the medium, and low dose of DIDS impaired CCL19/CCL21-induced Ca2+ influx, cell volume change, and DC migration. High doses of DIDS completely blocked DC migration possibly by significantly disrupting mitochondrial membrane potential. In conclusion, KCa3.1 and chloride channel are critical in human DC migration by synergistically regulating membrane potential, chemokine-induced Ca2+ influx, and cell volume. PMID:25583444

  5. Intermediate-conductance calcium-activated potassium channel KCa3.1 and chloride channel modulate chemokine ligand (CCL19/CCL21)-induced migration of dendritic cells.

    PubMed

    Shao, Zhifei; Gaurav, Rohit; Agrawal, Devendra K

    2015-07-01

    The role of ion channels is largely unknown in chemokine-induced migration in nonexcitable cells such as dendritic cells (DCs). Here, we examined the role of intermediate-conductance calcium-activated potassium channel (KCa3.1) and chloride channel (CLC3) in lymphatic chemokine-induced migration of DCs. The amplitude and kinetics of chemokine ligand (CCL19/CCL21)-induced Ca(2+) influx were associated with chemokine receptor 7 expression levels, extracellular-free Ca(2+) and Cl(-), and independent of extracellular K(+). Chemokines (CCL19 and CCL21) and KCa3.1 activator (1-ethyl-1,3-dihydro-2H-benzimidazol-2-one) induced plasma membrane hyperpolarization and K(+) efflux, which was blocked by 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole, suggesting that KCa3.1 carried larger conductance than the inward calcium release-activated calcium channel. Blockade of KCa3.1, low Cl(-) in the medium, and low dose of 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) impaired CCL19/CCL21-induced Ca(2+) influx, cell volume change, and DC migration. High doses of DIDS completely blocked DC migration possibly by significantly disrupting mitochondrial membrane potential. In conclusion, KCa3.1 and CLC3 are critical in human DC migration by synergistically regulating membrane potential, chemokine-induced Ca(2+) influx, and cell volume.

  6. Drinking modulates monocyte migration in healthy subjects: a randomised intervention study of water, ethanol, red wine and beer with or without alcohol.

    PubMed

    Imhof, Armin; Blagieva, Roza; Marx, Nikolaus; Koenig, Wolfgang

    2008-03-01

    Moderate alcohol consumption is associated with reduced cardiovascular mortality compared to non-consumption of alcohol and heavy drinking. Experimental data suggest a direct effect of alcohol on atherosclerotic lesion development. We assessed the effect of consumption of moderate amounts of alcoholic and non-alcoholic beverages on monocyte migration, a crucial step in atherogenesis. Forty-nine healthy men and women (aged 22-56 years) were enrolled in this randomised controlled trial. After wash-out, participants were assigned to either ethanol (concentration 12.5%), beer (5.6%) or red wine (12.5%) equivalent to 30 grams of ethanol per day (g/d) for men and 20 g/d for women, or to the same amount of de-alcoholised beer or red wine, or to water. Monocyte migration was evaluated ex vivo using a modified Boyden chamber. Intake of ethanol or de-alcoholised red wine significantly reduced monocyte chemoattractant protein-1 (MCP-1)-induced monocyte migration by 58% (p<0.05; n=6) and 36% (p<0.05; n=7) and FMLP (N-formyl-methionyl-leucyl-phenylalanine)-induced migration by 41% (p<0.05) and 36% (p<0.05), respectively. MCP-1 receptor expression was not affected by these interventions, as shown by flow cytometry. Short-term intervention with moderate amounts of ethanol and de-alcoholised red wine inhibits monocyte migration ex vivo. This might represent one mechanism by which alcoholic beverages lower cardiovascular risk.

  7. The CLC-2 Chloride Channel Modulates ECM Synthesis, Differentiation, and Migration of Human Conjunctival Fibroblasts via the PI3K/Akt Signaling Pathway.

    PubMed

    Sun, Lixia; Dong, Yaru; Zhao, Jing; Yin, Yuan; Zheng, Yajuan

    2016-06-09

    Recent evidence suggests that chloride channels are critical for cell proliferation, migration, and differentiation. We examined the effects of transforming growth factor (TGF)-β1 on chloride channel expression and associations with human conjunctival fibroblast (HConF) biology. To investigate the potential role of chloride channel (CLC)-2 in migration, transition to myofibroblasts and extracellular matrix (ECM) synthesis of HconF, a small interfering RNA (siRNA) approach was applied. TGF-β1-induced migration and transition of fibroblasts to myofibroblasts characterized by α-smooth muscle actin (α-SMA) expression, supported by increased endogenous expression of CLC-2 protein and mRNA transcripts. ECM (collagen I and fibronectin) synthesis in HConF was enhanced by TGF-β1. CLC-2 siRNA treatment reduced TGF-β1-induced cell migration, transition of fibroblasts to myofibroblasts, and ECM synthesis of HConF. CLC-2 siRNA treatment in the presence of TGF-β1 inhibited phosphorylation of PI3K and Akt in HConF. These findings demonstrate that CLC-2 chloride channels are important for TGF-β1-induced migration, differentiation, and ECM synthesis via PI3K/Akt signaling in HConF.

  8. Lactate-Modulated Induction of THBS-1 Activates Transforming Growth Factor (TGF)-beta2 and Migration of Glioma Cells In Vitro

    PubMed Central

    Moeckel, Sylvia; Jachnik, Birgit; Lottaz, Claudio; Kreutz, Marina; Brawanski, Alexander; Proescholdt, Martin; Bogdahn, Ulrich; Bosserhoff, Anja-Katrin; Vollmann-Zwerenz, Arabel; Hau, Peter

    2013-01-01

    Background An important phenomenon observed in glioma metabolism is increased aerobic glycolysis in tumor cells, which is generally referred to as the Warburg effect. Transforming growth factor (TGF)-beta2, which we previously showed to be induced by lactic acid, is a key pathophysiological factor in glioblastoma, leading to increased invasion and severe local immunosuppression after proteolytic cleavage from its latency associated peptide. In this study we tested the hypothesis, that lactate regulates TGF-beta2 expression and glioma cell migration via induction of Thrombospondin-1 (THBS-1), a TGF-beta activating protein. Methods Lactate levels were reduced by knockdown of LDH-A using specific small interfering RNA (siRNA) and competitive inhibition of LDH-A by sodium oxamate. Knockdown of THBS-1 was performed using specific siRNA. Western Blot, qRT-PCR, and ELISA were used to investigate expression levels of LDH-A, LDH-B, TGF-beta2 and THBS-1. Migration of cells was examined by Spheroid, Scratch and Boyden Chamber assays. Results Knockdown of LDH-A with subsequent decrease of lactate concentration leads to reduced levels of THBS-1 and TGF-beta2 in glioma cells. Lactate addition increases THBS-1 protein, leading to increased activation of TGF-beta2. Inhibition of THBS-1 reduces TGF-beta2 protein and migration of glioma cells. Addition of synthetic THBS-1 can rescue reduced TGF-beta2 protein levels and glioma cell migration in siLDH-A treated cells. Conclusion We define a regulatory cascade between lactate, THBS-1 and TGF-beta2, leading to enhanced migration of glioma cells. Our results demonstrate a specific interaction between tumor metabolism and migration and provide a better understanding of the mechanisms underlying glioma cell invasion. PMID:24223867

  9. Targeting the metastasis suppressor, NDRG1, using novel iron chelators: regulation of stress fiber-mediated tumor cell migration via modulation of the ROCK1/pMLC2 signaling pathway.

    PubMed

    Sun, Jing; Zhang, Daohai; Zheng, Ying; Zhao, Qian; Zheng, Minhua; Kovacevic, Zaklina; Richardson, Des R

    2013-02-01

    The iron-regulated metastasis suppressor, N-myc downstream-regulated gene 1 (NDRG1), is up-regulated by cellular iron depletion mediated by iron chelators and can inhibit cancer cell migration. However, the mechanism of how NDRG1 achieves this effect remains unclear. In this study, we implemented established and newly constructed NDRG1 overexpression and knockdown models using the DU145, HT29, and HCT116 cancer cell lines to investigate the molecular basis by which NDRG1 exerts its inhibitory effect on cell migration. Using these models, we demonstrated that NDRG1 overexpression inhibits cell migration by preventing actin-filament polymerization, stress fiber assembly and formation. In contrast, NDRG1 knockdown had the opposite effect. Moreover, we identified that NDRG1 inhibited an important regulatory pathway mediated by the Rho-associated, coiled-coil containing protein kinase 1 (ROCK1)/phosphorylated myosin light chain 2 (pMLC2) pathway that modulates stress fiber assembly. The phosphorylation of MLC2 is a key process in inducing stress fiber contraction, and this was shown to be markedly decreased or increased by NDRG1 overexpression or knockdown, respectively. The mechanism involved in the inhibition of MLC2 phosphorylation by NDRG1 was mediated by a significant (P < 0.001) decrease in ROCK1 expression that is a key kinase involved in MLC2 phosphorylation. Considering that NDRG1 is up-regulated after cellular iron depletion, novel thiosemicarbazone iron chelators (e.g., di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone) were demonstrated to inhibit ROCK1/pMLC2-modulated actin-filament polymerization, stress fiber assembly, and formation via a mechanism involving NDRG1. These results highlight the role of the ROCK1/pMLC2 pathway in the NDRG1-mediated antimetastatic signaling network and the therapeutic potential of iron chelators at inhibiting metastasis.

  10. Substrate curvature regulates cell migration

    NASA Astrophysics Data System (ADS)

    He, Xiuxiu; Jiang, Yi

    2017-06-01

    Cell migration is essential in many aspects of biology. Many basic migration processes, including adhesion, membrane protrusion and tension, cytoskeletal polymerization, and contraction, have to act in concert to regulate cell migration. At the same time, substrate topography modulates these processes. In this work, we study how substrate curvature at micrometer scale regulates cell motility. We have developed a 3D mechanical model of single cell migration and simulated migration on curved substrates with different curvatures. The simulation results show that cell migration is more persistent on concave surfaces than on convex surfaces. We have further calculated analytically the cell shape and protrusion force for cells on curved substrates. We have shown that while cells spread out more on convex surfaces than on concave ones, the protrusion force magnitude in the direction of migration is larger on concave surfaces than on convex ones. These results offer a novel biomechanical explanation to substrate curvature regulation of cell migration: geometric constrains bias the direction of the protrusion force and facilitates persistent migration on concave surfaces.

  11. Substrate curvature regulates cell migration.

    PubMed

    He, Xiuxiu; Jiang, Yi

    2017-05-23

    Cell migration is essential in many aspects of biology. Many basic migration processes, including adhesion, membrane protrusion and tension, cytoskeletal polymerization, and contraction, have to act in concert to regulate cell migration. At the same time, substrate topography modulates these processes. In this work, we study how substrate curvature at micrometer scale regulates cell motility. We have developed a 3D mechanical model of single cell migration and simulated migration on curved substrates with different curvatures. The simulation results show that cell migration is more persistent on concave surfaces than on convex surfaces. We have further calculated analytically the cell shape and protrusion force for cells on curved substrates. We have shown that while cells spread out more on convex surfaces than on concave ones, the protrusion force magnitude in the direction of migration is larger on concave surfaces than on convex ones. These results offer a novel biomechanical explanation to substrate curvature regulation of cell migration: geometric constrains bias the direction of the protrusion force and facilitates persistent migration on concave surfaces.

  12. [Internal migration].

    PubMed

    Borisovna, L

    1991-06-01

    Very few studies have been conducted that truly permit explanation of internal migration and it repercussions on social and economic structure. It is clear however that a profound knowledge of the determinants and consequences of internal migration will be required as a basis for economic policy decisions that advance the goal of improving the level of living of the population. the basic supposition of most studies of the relationship of population and development is that socioeconomic development conditions demographic dynamics. The process of development in Mexico, which can be characterized by great heterogeneity, consequently produces great regional disparities. At the national level various studies have estimated the volume of internal migration in Mexico, but they have usually been limited to interstate migration because the main source of data, the census, is classified by states. But given the great heterogeneity within states in all the elements related to internal migration, it is clear that studies of internal migration within states are also needed. Such studies are almost nonexistent because of their technical difficulty. National level studies show that interstate migration increased significantly between 1940-80. The proportion of Mexicans living outside their states of birth increased by 558% in those years, compared to the 342% increase in the total Mexican population. Although Puebla has a high rate of increase, migration has kept it below Mexico's national growth rate. Migration between Puebla and other states and within Puebla has led to an increasing unevenness of spatial distribution. Between 1970-80, 57 of Puebla's municipios had growth rates above the state average of 2.8%/year, 6 had growth rates equal to the average, and 129 had growth rates that were below the average but not negative. 25 states with negative growth rates that were considered strongly expulsive. In 1980, 51.7% of the population was concentrated in the 57 municipios

  13. Upregulation of long noncoding RNA SPRY4-IT1 modulates proliferation, migration, apoptosis, and network formation in trophoblast cells HTR-8SV/neo.

    PubMed

    Zou, Yanfen; Jiang, Ziyan; Yu, Xiang; Sun, Ming; Zhang, Yuanyuan; Zuo, Qing; Zhou, Jing; Yang, Nana; Han, Ping; Ge, Zhiping; De, Wei; Sun, Lizhou

    2013-01-01

    SPRY4-IT1 has been reported to have extremely high expression in normal placenta tissues. It is a Long noncoding RNA (lncRNA), which is associated with cell growth, migration, invasion, and apoptosis in melanoma. A 2.8-fold increase of SPRY4-IT1 expression was validated by Real-time reverse transcription-polymerase chain reaction (qRT-PCR) in severe preeclamptic placenta as compared with that of the normal ones (n=25) in this study. Furthermore, the role of SPRY4-IT1 in proliferation, migration, apoptosis, and network formation ability of trophoblast cells HTR-8/SVneo was assessed. Suppression of SPRY4-IT1 using siRNA treatment and its overexpression using plasmid targeting SPRY4-IT1 were performed in order to explore the biological function of SPRY4-IT1 in the development and progression of trophoblast cells HTR-8/SVneo, in vitro. The results showed that SPRY4-IT1 knockdown enhanced the cell migration and proliferation, and reduced the response of cells to apoptosis. However, exogenous SPRY4-IT1 overexpression significantly decreased the cell migration and proliferation, while increased cell apoptosis. Our study showed for the first time that aberrant expression of lncRNA SPRY4-IT1 might contribute to the abnormal condition of trophoblast cells HTR-8/SVneo. Therefore, we proposed SPRY4-IT1 as a novel lncRNA molecule, which might be associated with the pathogenesis of preeclampsia and might provide a new target for its early diagnosis and treatment.

  14. MicroRNA-106a suppresses proliferation, migration, and invasion of bladder cancer cells by modulating MAPK signaling, cell cycle regulators, and Ets-1-mediated MMP-2 expression.

    PubMed

    Shin, Seung-Shick; Park, Sung-Soo; Hwang, Byungdoo; Kim, Won Tae; Choi, Yung Hyun; Kim, Wun-Jae; Moon, Sung-Kwon

    2016-10-01

    Despite the clinical significance of tumorigenesis, little is known about the cellular signaling networks of microRNAs (miRs). Here we report a new finding that mir‑106a regulates the proliferation, migration, and invasion of bladder cancer cells. Basal expression levels of mir‑106a were significantly lower in bladder cancer cells than in normal urothelial cells. Overexpression of mir‑106a suppressed the proliferation of bladder cancer cell line EJ. Transient transfection of mir‑106a into EJ cells led to downregulation of ERK phosphorylation and upregulation of p38 and JNK phosphorylation over their levels in the control. Flow cytometry analysis revealed that mir‑106a-transfected cells accumulated in the G1-phase of the cell cycle, and cyclin D1 and CDK6 were significantly downregulated. This G1-phase cell cycle arrest was due in part to the upregulation of p21CIP1/WAF1. In addition, mir‑106a overexpression blocked the wound-healing migration and invasion of EJ cells. Furthermore, mir‑106a transfection resulted in decreased expression of MMP-2 and diminished binding activity of transcription factor Ets-1 in EJ cells. Collectively, we report the novel mir‑106a-mediated molecular signaling networks that regulate the proliferation, migration, and invasion of bladder cancer cells, suggesting that mir‑106a may be a therapeutic target for treating advanced bladder tumors.

  15. Notch 1 and 3 receptor signaling modulates vascular smooth muscle cell growth, apoptosis, and migration via a CBF-1/RBP-Jk dependent pathway.

    PubMed

    Sweeney, Catherine; Morrow, David; Birney, Yvonne A; Coyle, Seamus; Hennessy, Colm; Scheller, Agnieszka; Cummins, Philip M; Walls, Dermot; Redmond, Eileen M; Cahill, Paul A

    2004-09-01

    Vascular smooth muscle cell (SMC) fate decisions (cell growth, migration, and apoptosis) are fundamental features in the pathogenesis of vascular disease. We investigated the role of Notch 1 and 3 receptor signaling in controlling adult SMC fate in vitro by establishing that hairy enhancer of split (hes-1 and -5) and related hrt's (hrt-1, -2, and -3) are direct downstream target genes of Notch 1 and 3 receptors in SMC and identified an essential role for nuclear protein CBF-1/RBP-Jk in their regulation. Constitutive expression of active Notch 1 and 3 receptors (Notch IC) resulted in a significant up-regulation of CBF-1/RBP-Jk-dependent promoter activity and Notch target gene expression concomitant with significant increases in SMC growth while concurrently inhibiting SMC apoptosis and migration. Moreover, inhibition of endogenous Notch mediated CBF-1/RBP-Jk regulated gene expression with a non-DNA binding mutant of CBF-1, a Notch IC deleted of its delta RAM domain and the Epstein-Barr virus encoded RPMS-1, in conjunction with pharmacological inhibitors of Notch IC receptor trafficking (brefeldin A and monensin), resulted in a significant decrease in cell growth while concomitantly increasing SMC apoptosis and migration. These findings suggest that endogenous Notch receptors and downstream target genes control vascular cell fate in vitro. Notch signaling, therefore, represents a novel therapeutic target for disease states in which changes in vascular cell fate occur in vivo.

  16. Rubus idaeus extract suppresses migration and invasion of human oral cancer by inhibiting MMP-2 through modulation of the Erk1/2 signaling pathway.

    PubMed

    Huang, Yi-Wen; Chuang, Chun-Yi; Hsieh, Yih-Shou; Chen, Pei-Ni; Yang, Shun-Fa; Shih-Hsuan-Lin; Chen, Yang-Yu; Lin, Chiao-Wen; Chang, Yu-Chao

    2017-03-01

    Raspberries (Rubus idaeus L.) have been extensively studies worldwide because of their beneficial effects on health. Recently reports indicate that crude extracts of Rubus idaeus (RIE) have antioxidant and anticancer ability. The aim of this study was to evaluate the mechanism of its antimetastatic ability in oral cancer cells. In this study, SCC-9 and SAS oral cancer cells were subjected to a treatment with RIE and then analyzed the effect of RIE on migration and invasion. The addition of RIE inhibited the migration and invasion ability of oral cancer cells. Real time PCR, western blot and zymography analysis demonstrated that mRNA, protein expression and enzyme activity of matrix metalloproteinases-2 (MMP-2) were down-regulated by RIE. Moreover, the phosphorylation of Focal adhesion kinase (FAK), src, and extracellular signal-regulated kinase (ERK) were inhibited after RIE treatment. In conclusion, these results demonstrated that RIE exerted an inhibitory effect of migration and invasion in oral cancer cells and alter metastasis by suppression of MMP-2 expression through FAK/Scr/ERK signaling pathway. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1037-1046, 2017. © 2016 Wiley Periodicals, Inc.

  17. Dose-dependent modulation of HIF-1alpha/sima controls the rate of cell migration and invasion in Drosophila ovary border cells.

    PubMed

    Doronkin, S; Djagaeva, I; Nagle, M E; Reiter, L T; Seagroves, T N

    2010-02-25

    The role of the hypoxic response during metastasis was analysed in migrating border cells of the Drosophila ovary. Acute exposure to 1% O(2) delayed or blocked border cell migration (BCM), whereas prolonged exposure resulted in the first documented accelerated BCM phenotype. Similarly, manipulating the expression levels of sima, the Drosophila hypoxia-inducible factor (HIF)-1alpha ortholog, revealed that Sima can either block or restore BCM in a dose-dependent manner. In contrast, over-expression of Vhl (Drosophila von Hippel-Lindau) generated a range of phenotypes, including blocked, delayed and accelerated BCM, whereas over-expression of hph (Drosophila HIF prolyl hydroxylase) only accelerated BCM. Mosaic clone analysis of sima or tango (HIF-1beta ortholog) mutants revealed that cells lacking Hif-1 transcriptional activity were preferentially detected in the leading cell position of the cluster, resulting in either a delay or acceleration of BCM. Moreover, in sima mutant cell clones, there was reduced expression of nuclear slow border cells (Slbo) and basolateral DE-cadherin, proteins essential for proper BCM. These results show that Sima levels define the rate of BCM in part through regulation of Slbo and DE-cadherin, and suggest that dynamic regulation of Hif-1 activity is necessary to maintain invasive potential of migrating epithelial cells.

  18. Leupaxin stimulates adhesion and migration of prostate cancer cells through modulation of the phosphorylation status of the actin-binding protein caldesmon

    PubMed Central

    Schmidt, Thomas; Bremmer, Felix; Burfeind, Peter; Kaulfuß, Silke

    2015-01-01

    The focal adhesion protein leupaxin (LPXN) is overexpressed in a subset of prostate cancers (PCa) and is involved in the progression of PCa. In the present study, we analyzed the LPXN-mediated adhesive and cytoskeletal changes during PCa progression. We identified an interaction between the actin-binding protein caldesmon (CaD) and LPXN and this interaction is increased during PCa cell migration. Furthermore, knockdown of LPXN did not affect CaD expression but reduced CaD phosphorylation. This is known to destabilize the affinity of CaD to F-actin, leading to dynamic cell structures that enable cell motility. Thus, downregulation of CaD increased migration and invasion of PCa cells. To identify the kinase responsible for the LPXN-mediated phosphorylation of CaD, we used data from an antibody array, which showed decreased expression of TGF-beta-activated kinase 1 (TAK1) after LPXN knockdown in PC-3 PCa cells. Subsequent analyses of the downstream kinases revealed the extracellular signal-regulated kinase (ERK) as an interaction partner of LPXN that facilitates CaD phosphorylation during LPXN-mediated PCa cell migration. In conclusion, we demonstrate that LPXN directly influences cytoskeletal dynamics via interaction with the actin-binding protein CaD and regulates CaD phosphorylation by recruiting ERK to highly dynamic structures within PCa cells. PMID:26079947

  19. Myelin Proteolipid Protein Complexes with αv Integrin and AMPA Receptors In Vivo and Regulates AMPA-Dependent Oligodendrocyte Progenitor Cell Migration through the Modulation of Cell-Surface GluR2 Expression

    PubMed Central

    Harlow, Danielle E.; Saul, Katherine E.; Komuro, Hitoshi

    2015-01-01

    In previous studies, stimulation of ionotropic AMPA/kainate glutamate receptors on cultured oligodendrocyte cells induced the formation of a signaling complex that includes the AMPA receptor, integrins, calcium-binding proteins, and, surprisingly, the myelin proteolipid protein (PLP). AMPA stimulation of cultured oligodendrocyte progenitor cells (OPCs) also caused an increase in OPC migration. The current studies focused primarily on the formation of the PLP–αv integrin–AMPA receptor complex in vivo and whether complex formation impacts OPC migration in the brain. We found that in wild-type cerebellum, PLP associates with αv integrin and the calcium-impermeable GluR2 subunit of the AMPA receptor, but in mice lacking PLP, αv integrin did not associate with GluR2. Live imaging studies of OPC migration in ex vivo cerebellar slices demonstrated altered OPC migratory responses to neurotransmitter stimulation in the absence of PLP and GluR2 or when αv integrin levels were reduced. Chemotaxis assays of purified OPCs revealed that AMPA stimulation was neither attractive nor repulsive but clearly increased the migration rate of wild-type but not PLP null OPCs. AMPA receptor stimulation of wild-type OPCs caused decreased cell-surface expression of the GluR2 AMPA receptor subunit and increased intracellular Ca2+ signaling, whereas PLP null OPCs did not reduce GluR2 at the cell surface or increase Ca2+ signaling in response to AMPA treatment. Together, these studies demonstrate that PLP is critical for OPC responses to glutamate signaling and has important implications for OPC responses when levels of glutamate are high in the extracellular space, such as following demyelination. SIGNIFICANCE STATEMENT After demyelination, such as occurs in multiple sclerosis, remyelination of axons is often incomplete, leading to loss of neuronal function and clinical disability. Remyelination may fail because oligodendrocyte precursor cells (OPCs) do not completely migrate into

  20. Migration Theories

    NASA Astrophysics Data System (ADS)

    Crida, Aurélien

    2015-08-01

    The great variety of the architectures of the extra-solar planetary systems has revealed the fundamental role played by planetary migration: the interactions between the planets and the gaseous disk in which they form leads to a modification of their orbits. Here, I will review the basic processes and the most recent results in this area.Planets up to ~50 Earth masses are prone to so-called type I migration.I will describe the processes at play, namely the Lindblad and corotation torques, and explain how the total torque depends on the planet mass and the local disk structure. Application to realistic disks shows one or two sweet spot(s) for outward migration of planets roughly between 5 and 30 Earth masses around the snowline ; this is confirmed by dedicated 3D numerical simulations. This has strong consequences on the formation of hot Super-Earths or mini-Neptunes.For smaller mass planets, it has been recently proposed that the heating of the neighboring gas by the luminous planet can lead to a positive torque, hence promoting outward migration. On the other hand, if the planet is not a heat source, a cold finger appears, whose resulting torque is negative. Applications of these two recent results should be discussed.Giant planets open gaps in the proto-planetary disk, and then are supposedly subject to type II migration, following the viscous accretion of the disk. This standard picture has been questioned recently, as gas appears to drift through the gap. Although the gap opening process is well understood in 2D for a planet on a fixed orbit, recent results on 3D simulations or migrating planets make the picture more accurate.Our ever better understanding of planet-disk interactions is of crucial importance as the statistics on extra solar systems keep growing and the results of these interactions are now imaged.

  1. The Long Non-Coding RNA XIST Interacted with MiR-124 to Modulate Bladder Cancer Growth, Invasion and Migration by Targeting Androgen Receptor (AR).

    PubMed

    Xiong, Yaoyao; Wang, Long; Li, Yuan; Chen, Minfeng; He, Wei; Qi, Lin

    2017-08-31

    Long non-coding RNA (lncRNA) X-inactive specific transcript (XIST) is involved in the progression of several tumors. The interaction between lncRNA and miRNA or miRNA's target genes is reported to play crucial roles in malignancy. In addition, Androgen receptor (AR) is considered to be involved in bladder cancer progression. In this study, we investigated the role of XIST in human bladder cancer and its interaction with miR-124 and AR. XIST and AR expression was detected in bladder tumor samples and cell lines. Effects of XIST and AR on bladder cancer cells growth, invasion and migration were analyzed. Bioinformatic analysis and luciferase assays were used to identify the interaction among XIST, AR and miR-124. The correlations of miR-124 with XIST and AR in bladder cancer samples were statistically analyzed. XIST and AR were upregulated in bladder cancer tissues and positively correlated. Higher XIST and AR expression were related to poorer TNM stage of bladder cancer. XIST knockdown reduced bladder cancer cells' proliferation, invasion and migration. While this inhibitory effect could be partially restored by AR overexpression. XIST inhibited miR-124 expression by directly targeting. Moreover, miR-124 could bind to the 3'UTR of AR to regulate its expression. MiR-124 inhibition partially restored the XIST knockdown-induced reduction of AR, c-myc, p27, MMP13 and MMP9 expression. In bladder cancer tissues, miR-124 level was inversely correlated with the expression of XIST and AR, respectively. These findings indicated that XIST might be an oncogenic lncRNA that promoted the bladder cancer growth, invasion and migration via miR-124 dependent AR regulation. © 2017 The Author(s). Published by S. Karger AG, Basel.

  2. Methylmercury-Dependent Increases in Fluo4 Fluorescence in Neonatal Rat Cerebellar Slices Depend on Granule Cell Migrational Stage and GABAA Receptor Modulation

    PubMed Central

    Bradford, Aaron B.; Mancini, Jayme D.

    2016-01-01

    Methylmercury (MeHg) disrupts cerebellar function, especially during development. Cerebellar granule cells (CGC), which are particularly susceptible to MeHg by unknown mechanisms, migrate during this process. Transient changes in intracellular Ca2+ (Ca2+i) are crucial to proper migration, and MeHg is well known to disrupt CGC Ca2+i regulation. Acutely prepared slices of neonatal rat cerebellum in conjunction with confocal microscopy and fluo4 epifluorescence were used to track changes induced by MeHg in CGC Ca2+i regulation in the external (EGL) and internal granule cell layers (IGL) as well as the molecular layer (ML). MeHg caused no cytotoxicity but did cause a time-dependent increase in fluo4 fluorescence that depended on the stage of CGC development. CGCs in the EGL were most susceptible to MeHg-induced increases in fluo4 fluorescence. MeHg increased fluorescence in CGC processes but only diffusely; Purkinje cells rarely fluoresced in these slices. Neither muscimol nor bicuculline alone altered baseline fluo4 fluorescence in any CGC layer, but each delayed the onset and reduced the magnitude of effect of MeHg on fluo4 fluorescence in the EGL and ML. In the IGL, both muscimol and bicuculline delayed the onset of MeHg-induced increases in fluo4 fluorescence but did not affect fluorescence magnitude. Thus, acute exposure to MeHg causes developmental stage-dependent increases in Ca2+i in CGCs. Effects are most prominent in CGCs during development or early stages of migration. GABAA receptors participate in an as yet unclear manner to MeHg-induced Ca2+i dysregulation of CGCs. PMID:26514794

  3. Migrating Planets

    NASA Astrophysics Data System (ADS)

    Murray, N.; Hansen, B.; Holman, M.; Tremaine, S.

    1998-01-01

    A planet orbiting in a disk of planetesimals can experience an instability in which it migrates to smaller orbital radii. Resonant interactions between the planet and planetesimals remove angular momentum from the planetesimals, increasing their eccentricities. Subsequently, the planetesimals either collide with or are ejected by the planet, reducing the semimajor