AMPA Receptor-mTOR Activation is Required for the Antidepressant-Like Effects of Sarcosine during the Forced Swim Test in Rats: Insertion of AMPA Receptor may Play a Role

Kuang-Ti Chen, Mang-Hung Tsai, Ching-Hsiang Wu, Ming-Jia Jou, I-Hua Wei, Chih-Chia Huang, Kuang-Ti Chen, Mang-Hung Tsai, Ching-Hsiang Wu, Ming-Jia Jou, I-Hua Wei, Chih-Chia Huang

Abstract

Sarcosine, an endogenous amino acid, is a competitive inhibitor of the type I glycine transporter and an N-methyl-d-aspartate receptor (NMDAR) coagonist. Recently, we found that sarcosine, an NMDAR enhancer, can improve depression-related behaviors in rodents and humans. This result differs from previous studies, which have reported antidepressant effects of NMDAR antagonists. The mechanisms underlying the therapeutic response of sarcosine remain unknown. This study examines the role of mammalian target of rapamycin (mTOR) signaling and α-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor (AMPAR) activation, which are involved in the antidepressant-like effects of several glutamatergic system modulators. The effects of sarcosine in a forced swim test (FST) and the expression levels of phosphorylated mTOR signaling proteins were examined in the absence or presence of mTOR and AMPAR inhibitors. In addition, the influence of sarcosine on AMPAR trafficking was determined by analyzing the phosphorylation of AMPAR subunit GluR1 at the PKA site (often considered an indicator for GluR1 membrane insertion in neurons). A single injection of sarcosine exhibited antidepressant-like effects in rats in the FST and rapidly activated the mTOR signaling pathway, which were significantly blocked by mTOR inhibitor rapamycin or the AMPAR inhibitor 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline (NBQX) pretreatment. Moreover, NBQX pretreatment eliminated the ability of sarcosine to stimulate the phosphorylated mTOR signaling proteins. Furthermore, GluR1 phosphorylation at its PKA site was significantly increased after an acute in vivo sarcosine treatment. The results demonstrated that sarcosine exerts antidepressant-like effects by enhancing AMPAR-mTOR signaling pathway activity and facilitating AMPAR membrane insertion. Highlights-A single injection of sarcosine rapidly exerted antidepressant-like effects with a concomitant increase in the activation of the mammalian target of rapamycin mTOR signaling pathway.-The antidepressant-like effects of sarcosine occur through the activated AMPAR-mTOR signaling pathway.-Sarcosine could enhance AMPAR membrane insertion via an AMPAR throughput.

Keywords: AMPA; NMDA; depression; mTOR; sarcosine.

Figures

Figure 1
Figure 1
Schemata demonstrating the timeline of the experiments for drugs administrations, behavioral tests, and time of sacrifice for western blots analysis. For acute sarcosine administration (A,B), rats were given saline or sarcosine (560 mg/kg, i.p.) once. The forced swim test (FST) was conducted 30 min later (A). At 24 h before FST, rats had a 15-min conditioning swim. To evaluate the general locomotor activity, rats were administrated with saline or sarcosine (560 mg/kg, i.p.) once. The elevated plus-maze test (EPM) was conducted 30 min later (B). Immediately after EPM, rats were sacrificed and then rapidly decapitated. The hippocampus was removed for biochemical analysis (B). For acute sarcosine administration in the absence or presence of mTOR and AMPAR inhibitors (C,D), either AMPA inhibitor (NBQX, 10 mg/kg, i.p.) or mTOR pathway inhibitor (rapamycin, 20 mg/kg, i.p.) was administrated 30 min before sarcosine (560 mg/kg, i.p.) or saline treatment. At 30 min after last injection, rats were then tested in an FST paradigm (C). In a separate study (D), naïve rats were randomly treated with either AMPA inhibitor (NBQX, 10 mg/kg, i.p.) or mTOR pathway inhibitor (rapamycin, 20 mg/kg, i.p.) was administrated 30 min before sarcosine (560 mg/kg, i.p.) treatment. Thirty minutes after last injection, rats were sacrificed and then rapidly decapitated. The hippocampus was removed for biochemical analysis.
Figure 2
Figure 2
The behaviors and representative Western blotting of rats in forced swim test after acute administration with saline or sarcosine (560 mg/kg, i.p.). In the acute treatment scored by computer (A), the rats received a single injection of sarcosine prior to FST showed a significant reduction in percentage of immobility time. In the acute treatment scored manually (B), the rats received a single injection of sarcosine prior to FST showed a considerable reduction in immobility and an increase in climbing. The general activity [(C), numbers of closed arm entries and (D), total distance moved] of rats in the elevated plus maze (EPM) after acute administration with saline or sarcosine. The total closed arm entries (C) and distance moved (D) in EPM were measured to determine if sarcosine could produce a general increase in general locomotor activity that could yield a false-positive result on the FST. At the doses tested, none increased locomotor activity. Western blots analysis shows a notably increased expression of pmTOR, pERK, and pAkt in rat hippocampus following acute sarcosine treatment (E). The densitometry analysis of the blot (normalized to β-actin) verifies the enhanced activity of pmTOR (F), pERK (G), and pAkt (H) in each group of the experiments. (*p < 0.05; **p < 0.01; ***p < 0.001 compared with saline-treated group as assessed by t-test, Values shown are mean ± SEM, n = 10 for FST; n = 8 for EPM; n = 4 for western blots analysis per group).
Figure 3
Figure 3
The behaviors scored by computer (A) (percentage of immobility time) and manually (B) (frequency of immobility, swimming, climbing) of rats after acute sarcosine (560 mg/kg, i.p.) administration with pretreatment with NBQX (10 mg/kg, i.p.) or rapamycin (20 mg/kg, i.p.) in FST test. Note that the decreased immobility and increased climbing resulted from acute sarcosine treatment is blocked when rats were pretreated with rapamycin. Similar effect is evidently observed when rats were pretreated with NBQX. (*p < 0.05; **p < 0.01 compared with saline/saline-treated group; #p < 0.05, ##p < 0.01 compared with saline/sarcosine-treated group with Tukey post hoc analysis, Values shown are mean ± SEM, n = 8–9 per group).
Figure 4
Figure 4
Representative Western blotting (A) and relative expression ratio of pmTOR (B), pERK (C), and pAkt (D) in the hippocampus of rats after acute sarcosine (560 mg/kg, i.p.) administration with pretreatment with NBQX (10 mg/kg, i.p.) or rapamycin (20 mg/kg, i.p.). Western blots analysis shows a notably increased expression of pmTOR, pERK, and pAkt in rat hippocampus following acute sarcosine treatment. Note that the increased expression of pmTOR, pERK, and pAkt resulted from acute sarcosine treatment is blocked when rats were pretreated with NBQX. The increased expression of pmTOR resulted from acute sarcosine treatment is blocked when rats were pretreated with rapamycin and the increased expression of pERK and pAkt resulted from acute sarcosine treatment is not blocked (*p < 0.05; **p < 0.01 compared with saline/saline-treated group; ##p < 0.01, ###p < 0.001 compared with saline/sarcosine-treated group with Tukey post hoc analysis. Values shown are mean ± SEM, n = 4 per group).
Figure 5
Figure 5
Representative Western blotting of pGluR1 Ser845 from hippocampal slices of rats treated with saline or sarcosine (A) (560 mg/kg, i.p.) and after acute sarcosine (560 mg/kg, i.p.) administration with pretreatment with NBQX (10 mg/kg, i.p.) or rapamycin (20 mg/kg, i.p.) (B). Acute sarcosine treatment significantly increases the expression of pGluR1 Ser845. The increased expression of pGluR1 Ser845 resulted from acute sarcosine treatment is blocked when rats were pretreated with NBQX (B). But, the effect was not blocked by pretreatment with rapamycin (B). (*p < 0.05; **p < 0.01; ***p < 0.001 compared with saline/saline-treated group; ###p < 0.001 compared with saline/sarcosine-treated group with Tukey post hoc analysis. Values shown are mean ± SEM, n = 4 per group).
Figure 6
Figure 6
Proposed cellular mechanisms underlying antidepressant-like effects of sarcosine. Sarcosine caused the increased synaptic availability of glycine via inhibiting glycine uptake facilitates. The activation of synaptic NMDAR with co-agonist glycine induces AMPAR insertion into post-synaptic membrane that will amplify post-synaptic AMPAR levels, leading to increased AMPAR/NMDAR stimulation. Increased AMPAR throughput may ultimately cause downstream neuroproliferative effects through the activation of mTOR and multiple intracellular signaling cascades. Finally, sarcosine exhibit antidepressant-like property.

References

    1. Banke T. G., Bowie D., Lee H., Huganir R. L., Schousboe A., Traynelis S. F. (2000). Control of GluR1 AMPA receptor function by cAMP-dependent protein kinase. J. Neurosci. 20, 89–102.
    1. Campbell S., Macqueen G. (2004). The role of the hippocampus in the pathophysiology of major depression. J. Psychiatry Neurosci. 29, 417–426.
    1. Chen N., Napoli J. L. (2008). All-trans-retinoic acid stimulates translation and induces spine formation in hippocampal neurons through a membrane-associated RARalpha. FASEB J. 22, 236–245.10.1096/fj.07-8739com
    1. Cleary C., Linde J. A., Hiscock K. M., Hadas I., Belmaker R. H., Agam G., et al. (2008). Antidepressive-like effects of rapamycin in animal models: implications for mTOR inhibition as a new target for treatment of affective disorders. Brain Res. Bull. 76, 469–473.10.1016/j.brainresbull.2008.03.005
    1. Cryan J. F., Page M. E., Lucki I. (2005). Differential behavioral effects of the antidepressants reboxetine, fluoxetine, and moclobemide in a modified forced swim test following chronic treatment. Psychopharmacology (Berl.) 182, 335–344.10.1007/s00213-005-0093-5
    1. Dahl M., Bouchelouche P., Kramer-Marek G., Capala J., Nordling J., Bouchelouche K. (2011). Sarcosine induces increase in HER2/neu expression in androgen-dependent prostate cancer cells. Mol. Biol. Rep. 38, 4237–4243.10.1007/s11033-010-0442-2
    1. Depoortere R., Dargazanli G., Estenne-Bouhtou G., Coste A., Lanneau C., Desvignes C., et al. (2005). Neurochemical, electrophysiological and pharmacological profiles of the selective inhibitor of the glycine transporter-1 SSR504734, a potential new type of antipsychotic. Neuropsychopharmacology 30, 1963–1985.10.1038/sj.npp.1300772
    1. Detke M. J., Johnson J., Lucki I. (1997). Acute and chronic antidepressant drug treatment in the rat forced swimming test model of depression. Exp. Clin. Psychopharmacol. 5, 107–112.10.1037/1064-1297.5.2.107
    1. Du J., Machado-Vieira R., Maeng S., Martinowich K., Manji H. K., Zarate C. A., Jr. (2006). Enhancing AMPA to NMDA throughput as a convergent mechanism for antidepressant action. Drug Discov. Today Ther. Strateg. 3, 519–526.10.1016/j.ddstr.2006.11.012
    1. Du J., Suzuki K., Wei Y., Wang Y., Blumenthal R., Chen Z., et al. (2007). The anticonvulsants lamotrigine, riluzole, and valproate differentially regulate AMPA receptor membrane localization: relationship to clinical effects in mood disorders. Neuropsychopharmacology 32, 793–802.10.1038/sj.npp.1301178
    1. Dwyer J. M., Lepack A. E., Duman R. S. (2012). mTOR activation is required for the antidepressant effects of mGluR(2)/(3) blockade. Int. J. Neuropsychopharmacol. 15, 429–434.10.1017/s1461145711001702
    1. Encinas J. M., Fernandez A. P., Salas E., Castro-Blanco S., Munoz P., Rodrigo J., et al. (2004). Nitric oxide synthase and NADPH-diaphorase after acute hypobaric hypoxia in the rat caudate putamen. Exp. Neurol. 186, 33–45.10.1016/j.expneurol.2003.09.024
    1. Esteban J. A., Shi S. H., Wilson C., Nuriya M., Huganir R. L., Malinow R. (2003). PKA phosphorylation of AMPA receptor subunits controls synaptic trafficking underlying plasticity. Nat. Neurosci. 6, 136–143.10.1038/nn997
    1. Fekadu A., Wooderson S. C., Markopoulo K., Donaldson C., Papadopoulos A., Cleare A. J. (2009). What happens to patients with treatment-resistant depression? A systematic review of medium to long term outcome studies. J. Affect. Disord. 116, 4–11.10.1016/j.jad.2008.10.014
    1. Hashimoto K. (2011). The role of glutamate on the action of antidepressants. Prog. Neuropsychopharmacol. Biol. Psychiatry 35, 1558–1568.10.1016/j.pnpbp.2010.06.013
    1. Hay N., Sonenberg N. (2004). Upstream and downstream of mTOR. Genes Dev. 18, 1926–1945.10.1101/gad.1212704
    1. Hoeffer C. A., Klann E. (2010a). mTOR signaling: at the crossroads of plasticity, memory and disease. Trends Neurosci. 33, 67–75.10.1016/j.tins.2009.11.003
    1. Hoeffer C. A., Klann E. (2010b). mTOR signaling: at the crossroads of plasticity, memory, and disease. Trends Neurosci. 33, 67.10.1016/j.tins.2009.11.003
    1. Hogg S. (1996). A review of the validity and variability of the elevated plus-maze as an animal model of anxiety. Pharmacol. Biochem. Behav. 54, 21–30.10.1016/0091-3057(95)02126-4
    1. Huang C. C., Wei I. H., Huang C. L., Chen K. T., Tsai M. H., Tsai P., et al. (2013). Inhibition of glycine transporter-I as a novel mechanism for the treatment of depression. Biol. Psychiatry 74, 734–741.10.1016/j.biopsych.2013.02.020
    1. Jernigan C. S., Goswami D. B., Austin M. C., Iyo A. H., Chandran A., Stockmeier C. A., et al. (2011). The mTOR signaling pathway in the prefrontal cortex is compromised in major depressive disorder. Prog. Neuropsychopharmacol. Biol. Psychiatry 35, 1774–1779.10.1016/j.pnpbp.2011.05.010
    1. Koike H., Chaki S. (2014). Requirement of AMPA receptor stimulation for the sustained antidepressant activity of ketamine and LY341495 during the forced swim test in rats. Behav. Brain Res. 271, 111–115.10.1016/j.bbr.2014.05.065
    1. Krystal J. H., Sanacora G., Blumberg H., Anand A., Charney D. S., Marek G., et al. (2002). Glutamate and GABA systems as targets for novel antidepressant and mood-stabilizing treatments. Mol. Psychiatry 7(Suppl. 1), S71–S80.10.1038/sj.mp.4001021
    1. Kugaya A., Sanacora G. (2005). Beyond monoamines: glutamatergic function in mood disorders. CNS Spectr. 10, 808–819.
    1. Li N., Lee B., Liu R. J., Banasr M., Dwyer J. M., Iwata M., et al. (2010). mTOR-dependent synapse formation underlies the rapid antidepressant effects of NMDA antagonists. Science 329, 959–964.10.1126/science.1190287
    1. Livingstone M., Atas E., Meller A., Sonenberg N. (2010). Mechanisms governing the control of mRNA translation. Phys. Biol. 7, 021001.10.1088/1478-3975/7/2/021001
    1. Lu W., Man H., Ju W., Trimble W. S., Macdonald J. F., Wang Y. T. (2001). Activation of synaptic NMDA receptors induces membrane insertion of new AMPA receptors and LTP in cultured hippocampal neurons. Neuron 29, 243–254.10.1016/S0896-6273(01)00194-5
    1. Maeng S., Zarate C. A., Jr. (2007). The role of glutamate in mood disorders: results from the ketamine in major depression study and the presumed cellular mechanism underlying its antidepressant effects. Curr. Psychiatry Rep. 9, 467–474.10.1007/s11920-007-0063-1
    1. Maeng S., Zarate C. A., Jr., Du J., Schloesser R. J., McCammon J., Chen G., et al. (2008). Cellular mechanisms underlying the antidepressant effects of ketamine: role of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors. Biol. Psychiatry 63, 349–352.10.1016/j.biopsych.2007.05.028
    1. Malkesman O., Austin D. R., Tragon T., Wang G., Rompala G., Hamidi A. B., et al. (2012). Acute d-serine treatment produces antidepressant-like effects in rodents. Int. J. Neuropsychopharmacol. 15, 1135–1148.10.1017/s1461145711001386
    1. Nestler E. J., Barrot M., Dileone R. J., Eisch A. J., Gold S. J., Monteggia L. M. (2002). Neurobiology of depression. Neuron 34, 13–25.10.1016/S0896-6273(02)00653-0
    1. Palucha-Poniewiera A., Szewczyk B., Pilc A. (2014). Activation of the mTOR signaling pathway in the antidepressant-like activity of the mGlu5 antagonist MTEP and the mGlu7 agonist AMN082 in the FST in rats. Neuropharmacology 82, 59–68.10.1016/j.neuropharm.2014.03.001
    1. Peng X., Kim J., Zhou Z., Fink D. J., Mata M. (2011). Neuronal Nogo-A regulates glutamate receptor subunit expression in hippocampal neurons. J. Neurochem. 119, 1183–1193.10.1111/j.1471-4159.2011.07520.x
    1. Porsolt R. D., Bertin A., Jalfre M. (1977). Behavioral despair in mice: a primary screening test for antidepressants. Arch. Int. Pharmacodyn. Ther. 229, 327–336.
    1. Reus G. Z., Stringari R. B., Ribeiro K. F., Ferraro A. K., Vitto M. F., Cesconetto P., et al. (2011). Ketamine plus imipramine treatment induces antidepressant-like behavior and increases CREB and BDNF protein levels and PKA and PKC phosphorylation in rat brain. Behav. Brain Res. 221, 166–171.10.1016/j.bbr.2011.02.024
    1. Rizvi S. J., Grima E., Tan M., Rotzinger S., Lin P., McIntyre R. S., et al. (2014). Treatment-resistant depression in primary care across Canada. Can. J. Psychiatry 59, 349–357.
    1. Rodgers R. J., Johnson N. J. (1995). Factor analysis of spatiotemporal and ethological measures in the murine elevated plus-maze test of anxiety. Pharmacol. Biochem. Behav. 52, 297–303.10.1016/0091-3057(95)00138-M
    1. Schloesser R. J., Huang J., Klein P. S., Manji H. K. (2008). Cellular plasticity cascades in the pathophysiology and treatment of bipolar disorder. Neuropsychopharmacology 33, 110–133.10.1038/sj.npp.1301575
    1. Shimizu-Sasamata M., Kawasaki-Yatsugi S., Okada M., Sakamoto S., Yatsugi S., Togami J., et al. (1996). YM90K: pharmacological characterization as a selective and potent alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate/kainate receptor antagonist. J. Pharmacol. Exp. Ther. 276, 84–92.
    1. Shor B., Gibbons J. J., Abraham R. T., Yu K. (2009). Targeting mTOR globally in cancer: thinking beyond rapamycin. Cell Cycle 8, 3831–3837.10.4161/cc.8.23.10070
    1. Skolnick P. (1999). Antidepressants for the new millennium. Eur. J. Pharmacol. 375, 31–40.10.1016/S0014-2999(99)00330-1
    1. Slipczuk L., Bekinschtein P., Katche C., Cammarota M., Izquierdo I., Medina J. H. (2009). BDNF activates mTOR to regulate GluR1 expression required for memory formation. PLoS ONE 4:e6007.10.1371/journal.pone.0006007
    1. Smith K. E., Borden L. A., Hartig P. R., Branchek T., Weinshank R. L. (1992). Cloning and expression of a glycine transporter reveal colocalization with NMDA receptors. Neuron 8, 927–935.10.1016/0896-6273(92)90207-T
    1. Smith K. E., Gibson E. S., Dell’acqua M. L. (2006). cAMP-dependent protein kinase postsynaptic localization regulated by NMDA receptor activation through translocation of an A-kinase anchoring protein scaffold protein. J. Neurosci. 26, 2391–2402.10.1523/jneurosci.3092-05.2006
    1. Sreekumar A., Poisson L. M., Rajendiran T. M., Khan A. P., Cao Q., Yu J., et al. (2009). Metabolomic profiles delineate potential role for sarcosine in prostate cancer progression. Nature 457, 910–914.10.1038/nature07762
    1. Stewart C. A., Reid I. C. (2002). Antidepressant mechanisms: functional and molecular correlates of excitatory amino acid neurotransmission. Mol. Psychiatry 7(Suppl. 1), S15–S22.10.1038/sj.mp.4001014
    1. Tokita K., Yamaji T., Hashimoto K. (2012). Roles of glutamate signaling in preclinical and/or mechanistic models of depression. Pharmacol. Biochem. Behav. 100, 688–704.10.1016/j.pbb.2011.04.016
    1. Trivedi M. H., Fava M., Wisniewski S. R., Thase M. E., Quitkin F., Warden D., et al. (2006). Medication augmentation after the failure of SSRIs for depression. N. Engl. J. Med. 354, 1243–1252.10.1056/NEJMoa052964
    1. Voleti B., Navarria A., Liu R. J., Banasr M., Li N., Terwilliger R., et al. (2013). Scopolamine rapidly increases mammalian target of rapamycin complex 1 signaling, synaptogenesis, and antidepressant behavioral responses. Biol. Psychiatry 74, 742–749.10.1016/j.biopsych.2013.04.025
    1. Wang Y., Barbaro M. F., Baraban S. C. (2006). A role for the mTOR pathway in surface expression of AMPA receptors. Neurosci. Lett. 401, 35–39.10.1016/j.neulet.2006.03.011
    1. Zarate C. A., Jr., Singh J., Manji H. K. (2006a). Cellular plasticity cascades: targets for the development of novel therapeutics for bipolar disorder. Biol. Psychiatry 59, 1006–1020.10.1016/j.biopsych.2005.10.021
    1. Zarate C. A., Jr., Singh J. B., Carlson P. J., Brutsche N. E., Ameli R., Luckenbaugh D. A., et al. (2006b). A randomized trial of an N-methyl-d-aspartate antagonist in treatment-resistant major depression. Arch. Gen. Psychiatry 63, 856–864.10.1001/archpsyc.63.8.856
    1. Zarate C. A., Jr., Singh J. B., Quiroz J. A., De Jesus G., Denicoff K. K., Luckenbaugh D. A., et al. (2006c). A double-blind, placebo-controlled study of memantine in the treatment of major depression. Am. J. Psychiatry 163, 153–155.10.1176/appi.ajp.163.1.153
    1. Zhang H. X., Hyrc K., Thio L. L. (2009). The glycine transport inhibitor sarcosine is an NMDA receptor co-agonist that differs from glycine. J. Physiol. 587, 3207–3220.10.1113/jphysiol.2009.168757

Source: PubMed

スポンサーと協力者

医学的状態

薬物療法

3
購読する