Advertisement

Serine Racemase and D-serine in the Amygdala Are Dynamically Involved in Fear Learning

      Abstract

      Background

      The amygdala is a central component of the neural circuitry that underlies fear learning. N-methyl-D-aspartate receptor–dependent plasticity in the amygdala is required for pavlovian fear conditioning and extinction. N-methyl-D-aspartate receptor activation requires the binding of a coagonist, D-serine, which is synthesized from L-serine by the neuronal enzyme serine racemase (SR). However, little is known about SR and D-serine function in the amygdala.

      Methods

      We used immunohistochemical methods to characterize the cellular localization of SR and D-serine in the mouse and human amygdala. Using biochemical and molecular techniques, we determined whether trace fear conditioning and extinction engages the SR/D-serine system in the brain. D-serine was administered systemically to mice to evaluate its effect on fear extinction. Finally, we investigated whether the functional single nucleotide polymorphism rs4523957, which is an expression quantitative trait locus of the human serine racemase (SRR) gene, was associated with fear-related phenotypes in a highly traumatized human cohort.

      Results

      We demonstrate that approximately half of the neurons in the amygdala express SR, including both excitatory and inhibitory neurons. We find that the acquisition and extinction of fear memory engages the SR/D-serine system in the mouse amygdala and that D-serine administration facilitates fear extinction. We also demonstrate that the SRR single nucleotide polymorphism, rs4523957, is associated with posttraumatic stress disorder in humans, consistent with the facilitatory effect of D-serine on fear extinction.

      Conclusions

      These new findings have important implications for understanding D-serine–mediated N-methyl-D-aspartate receptor plasticity in the amygdala and how this system could contribute to disorders with maladaptive fear circuitry.

      Keywords

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to Biological Psychiatry
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Paoletti P.
        • Bellone C.
        • Zhou Q.
        NMDA receptor subunit diversity: Impact on receptor properties, synaptic plasticity and disease.
        Nat Rev Neurosci. 2013; 14: 383-400
        • Kleckner N.W.
        • Dingledine R.
        Requirement for glycine in activation of NMDA-receptors expressed in Xenopus oocytes.
        Science. 1988; 241: 835-837
        • Johnson J.W.
        • Ascher P.
        Glycine potentiates the NMDA response in cultured mouse brain neurons.
        Nature. 1987; 325: 529-531
        • Wolosker H.
        • Blackshaw S.
        • Snyder S.H.
        Serine racemase: A glial enzyme synthesizing D-serine to regulate glutamate-N-methyl-D-aspartate neurotransmission.
        Proc Natl Acad Sci U S A. 1999; 96: 13409-13414
        • Schell M.J.
        • Molliver M.E.
        • Snyder S.H.
        D-serine, an endogenous synaptic modulator: Localization to astrocytes and glutamate-stimulated release.
        Proc Natl Acad Sci U S A. 1995; 92: 3948-3952
        • Bergeron R.
        • Meyer T.M.
        • Coyle J.T.
        • Greene R.W.
        Modulation of N-methyl-D-aspartate receptor function by glycine transport.
        Proc Natl Acad Sci U S A. 1998; 95: 15730-15734
        • Papouin T.
        • Ladepeche L.
        • Ruel J.
        • Sacchi S.
        • Labasque M.
        • Hanini M.
        • et al.
        Synaptic and extrasynaptic NMDA receptors are gated by different endogenous coagonists.
        Cell. 2012; 150: 633-646
        • Balu D.T.
        • Li Y.
        • Puhl M.D.
        • Benneyworth M.A.
        • Basu A.C.
        • Takagi S.
        • et al.
        Multiple risk pathways for schizophrenia converge in serine racemase knockout mice, a mouse model of NMDA receptor hypofunction.
        Proc Natl Acad Sci U S A. 2013; 110: E2400-E2409
        • Basu A.C.
        • Tsai G.E.
        • Ma C.L.
        • Ehmsen J.T.
        • Mustafa A.K.
        • Han L.
        • et al.
        Targeted disruption of serine racemase affects glutamatergic neurotransmission and behavior.
        Mol Psychiatry. 2009; 14: 719-727
        • Le Bail M.
        • Martineau M.
        • Sacchi S.
        • Yatsenko N.
        • Radzishevsky I.
        • Conrod S.
        • et al.
        Identity of the NMDA receptor coagonist is synapse specific and developmentally regulated in the hippocampus.
        Proc Natl Acad Sci U S A. 2015; 112: E204-E213
        • Li Y.
        • Sacchi S.
        • Pollegioni L.
        • Basu A.C.
        • Coyle J.T.
        • Bolshakov V.Y.
        Identity of endogenous NMDAR glycine site agonist in amygdala is determined by synaptic activity level.
        Nat Commun. 2013; 4: 1760
        • Balu D.T.
        • Basu A.C.
        • Corradi J.P.
        • Cacace A.M.
        • Coyle J.T.
        The NMDA receptor co-agonists, D-serine and glycine, regulate neuronal dendritic architecture in the somatosensory cortex.
        Neurobiol Dis. 2012; 45: 671-682
        • Balu D.T.
        • Coyle J.T.
        Chronic D-serine reverses Arc expression and partially rescues dendritic abnormalities in a mouse model of NMDA receptor hypofunction.
        Neurochem Int. 2014; 75C: 76-78
        • Janak P.H.
        • Tye K.M.
        From circuits to behaviour in the amygdala.
        Nature. 2015; 517: 284-292
        • Bauer E.P.
        • Schafe G.E.
        • LeDoux J.E.
        NMDA receptors and L-type voltage-gated calcium channels contribute to long-term potentiation and different components of fear memory formation in the lateral amygdala.
        J Neurosci. 2002; 22: 5239-5249
        • Maren S.
        • Fanselow M.S.
        Synaptic plasticity in the basolateral amygdala induced by hippocampal formation stimulation in vivo.
        J Neurosci. 1995; 15: 7548-7564
        • Johansen J.P.
        • Cain C.K.
        • Ostroff L.E.
        • LeDoux J.E.
        Molecular mechanisms of fear learning and memory.
        Cell. 2011; 147: 509-524
        • LeDoux J.E.
        Emotion circuits in the brain.
        Annu Rev Neurosci. 2000; 23: 155-184
        • Balu D.T.
        • Li Y.
        • Takagi S.
        • Presti K.T.
        • Ramikie T.S.
        • Rook J.M.
        • et al.
        An mGlu5-positive allosteric modulator rescues the neuroplasticity deficits in a genetic model of NMDA receptor hypofunction in schizophrenia.
        Neuropsychopharmacology. 2016; 41: 2052-2061
        • Etkin A.
        • Wager T.D.
        Functional neuroimaging of anxiety: A meta-analysis of emotional processing in PTSD, social anxiety disorder, and specific phobia.
        Am J Psychiatry. 2007; 164: 1476-1488
        • Shimasaki A.
        • Kondo K.
        • Saito T.
        • Esaki K.
        • Otsuka Y.
        • Mano K.
        • et al.
        A genetic variant in 12q13, a possible risk factor for bipolar disorder, is associated with depressive state, accounting for stressful life events.
        PLoS One. 2014; 9: e115135
        • Van der Auwera S.
        • Teumer A.
        • Hertel J.
        • Homuth G.
        • Volker U.
        • Lucht M.J.
        • et al.
        The inverse link between genetic risk for schizophrenia and migraine through NMDA (N-methyl-D-aspartate) receptor activation via D-serine.
        Eur Neuropsychopharmacol. 2016; 26: 1507-1515
        • Zhang S.
        • Xiao J.
        • Ren Q.
        • Han X.
        • Tang Y.
        • Yang W.
        • et al.
        Association of serine racemase gene variants with type 2 diabetes in the Chinese Han population.
        J Diabetes Investig. 2014; 5: 286-289
        • Andero R.
        • Brothers S.P.
        • Jovanovic T.
        • Chen Y.T.
        • Salah-Uddin H.
        • Cameron M.
        • et al.
        Amygdala-dependent fear is regulated by Oprl1 in mice and humans with PTSD.
        Sci Transl Med. 2013; 5: 188ra173
        • Gillespie C.F.
        • Bradley B.
        • Mercer K.
        • Smith A.K.
        • Conneely K.
        • Gapen M.
        • et al.
        Trauma exposure and stress-related disorders in inner city primary care patients.
        Gen Hosp Psychiatry. 2009; 31: 505-514
        • Balu D.T.
        • Takagi S.
        • Puhl M.D.
        • Benneyworth M.A.
        • Coyle J.T.
        D-serine and serine racemase are localized to neurons in the adult mouse and human forebrain.
        Cell Mol Neurobiol. 2014; 34: 419-435
        • Balu D.T.
        • Coyle J.T.
        Glutamate receptor composition of the post-synaptic density is altered in genetic mouse models of NMDA receptor hypo- and hyperfunction.
        Brain Res. 2011; 1392: 1-7
        • Hashimoto A.
        • Nishikawa T.
        • Oka T.
        • Takahashi K.
        • Hayashi T.
        Determination of free amino acid enantiomers in rat brain and serum by high-performance liquid chromatography after derivatization with N-tert.-butyloxycarbonyl-L-cysteine and o-phthaldialdehyde.
        J Chromatogr. 1992; 582: 41-48
        • Purcell S.
        • Neale B.
        • Todd-Brown K.
        • Thomas L.
        • Ferreira M.A.
        • Bender D.
        • et al.
        PLINK: A tool set for whole-genome association and population-based linkage analyses.
        Am J Hum Genet. 2007; 81: 559-575
        • Ehmsen J.T.
        • Ma T.M.
        • Sason H.
        • Rosenberg D.
        • Ogo T.
        • Furuya S.
        • et al.
        D-serine in glia and neurons derives from 3-phosphoglycerate dehydrogenase.
        J Neurosci. 2013; 33: 12464-12469
        • Miya K.
        • Inoue R.
        • Takata Y.
        • Abe M.
        • Natsume R.
        • Sakimura K.
        • et al.
        Serine racemase is predominantly localized in neurons in mouse brain.
        J Comp Neurol. 2008; 510: 641-654
        • Wolosker H.
        • Balu D.T.
        • Coyle J.T.
        The rise and fall of the D-serine-mediated gliotransmission hypothesis.
        Trends Neurosci. 2016; 39: 712-721
        • Korb E.
        • Finkbeiner S.
        Arc in synaptic plasticity: From gene to behavior.
        Trends Neurosci. 2011; 34: 591-598
        • Czerniawski J.
        • Ree F.
        • Chia C.
        • Ramamoorthi K.
        • Kumata Y.
        • Otto T.A.
        The importance of having Arc: Expression of the immediate-early gene Arc is required for hippocampus-dependent fear conditioning and blocked by NMDA receptor antagonism.
        J Neurosci. 2011; 31: 11200-11207
        • Maddox S.A.
        • Schafe G.E.
        The activity-regulated cytoskeletal-associated protein (Arc/Arg3.1) is required for reconsolidation of a Pavlovian fear memory.
        J Neurosci. 2011; 31: 7073-7082
        • Ploski J.E.
        • Pierre V.J.
        • Smucny J.
        • Park K.
        • Monsey M.S.
        • Overeem K.A.
        • et al.
        The activity-regulated cytoskeletal-associated protein (Arc/Arg3.1) is required for memory consolidation of Pavlovian fear conditioning in the lateral amygdala.
        J Neurosci. 2008; 28: 12383-12395
        • Chau L.S.
        • Prakapenka A.
        • Fleming S.A.
        • Davis A.S.
        • Galvez R.
        Elevated Arc/Arg 3.1 protein expression in the basolateral amygdala following auditory trace-cued fear conditioning.
        Neurobiol Learn Mem. 2013; 106: 127-133
        • Onoue K.
        • Nakayama D.
        • Ikegaya Y.
        • Matsuki N.
        • Nomura H.
        Fear extinction requires Arc/Arg3.1 expression in the basolateral amygdala.
        Mol Brain. 2014; 7: 30
        • Singewald N.
        • Schmuckermair C.
        • Whittle N.
        • Holmes A.
        • Ressler K.J.
        Pharmacology of cognitive enhancers for exposure-based therapy of fear, anxiety and trauma-related disorders.
        Pharmacol Ther. 2015; 149: 150-190
        • McBain C.J.
        • Kleckner N.W.
        • Wyrick S.
        • Dingledine R.
        Structural requirements for activation of the glycine coagonist site of N-methyl-D-aspartate receptors expressed in Xenopus oocytes.
        Mol Pharmacol. 1989; 36: 556-565
        • Lin H.
        • Jacobi A.A.
        • Anderson S.A.
        • Lynch D.R.
        D-serine and serine racemase are associated with PSD-95 and glutamatergic synapse stability.
        Front Cell Neurosci. 2016; 10: 34
        • Duvarci S.
        • Pare D.
        Amygdala microcircuits controlling learned fear.
        Neuron. 2014; 82: 966-980
        • Ciocchi S.
        • Herry C.
        • Grenier F.
        • Wolff S.B.
        • Letzkus J.J.
        • Vlachos I.
        • et al.
        Encoding of conditioned fear in central amygdala inhibitory circuits.
        Nature. 2010; 468: 277-282
        • Tovote P.
        • Esposito M.S.
        • Botta P.
        • Chaudun F.
        • Fadok J.P.
        • Markovic M.
        • et al.
        Midbrain circuits for defensive behaviour.
        Nature. 2016; 534: 206-212
        • McCullough K.M.
        • Morrison F.G.
        • Ressler K.J.
        Bridging the gap: Towards a cell-type specific understanding of neural circuits underlying fear behaviors.
        Neurobiol Learn Mem. 2016; 135: 27-39
        • Gafford G.M.
        • Ressler K.J.
        Mouse models of fear-related disorders: Cell-type-specific manipulations in amygdala.
        Neuroscience. 2016; 321: 108-120
        • Haubensak W.
        • Kunwar P.S.
        • Cai H.
        • Ciocchi S.
        • Wall N.R.
        • Ponnusamy R.
        • et al.
        Genetic dissection of an amygdala microcircuit that gates conditioned fear.
        Nature. 2010; 468: 270-276
        • Li H.
        • Penzo M.A.
        • Taniguchi H.
        • Kopec C.D.
        • Huang Z.J.
        • Li B.
        Experience-dependent modification of a central amygdala fear circuit.
        Nat Neurosci. 2013; 16: 332-339
        • Penzo M.A.
        • Robert V.
        • Li B.
        Fear conditioning potentiates synaptic transmission onto long-range projection neurons in the lateral subdivision of central amygdala.
        J Neurosci. 2014; 34: 2432-2437
        • Balan L.
        • Foltyn V.N.
        • Zehl M.
        • Dumin E.
        • Dikopoltsev E.
        • Knoh D.
        • et al.
        Feedback inactivation of D-serine synthesis by NMDA receptor-elicited translocation of serine racemase to the membrane.
        Proc Natl Acad Sci U S A. 2009; 106: 7589-7594
        • Dikopoltsev E.
        • Foltyn V.N.
        • Zehl M.
        • Jensen O.N.
        • Mori H.
        • Radzishevsky I.
        • Wolosker H.
        FBXO22 protein is required for optimal synthesis of the N-methyl-D-aspartate (NMDA) receptor coagonist D-serine.
        J Biol Chem. 2014; 289: 33904-33915
        • Dumin E.
        • Bendikov I.
        • Foltyn V.N.
        • Misumi Y.
        • Ikehara Y.
        • Kartvelishvily E.
        • et al.
        Modulation of D-serine levels via ubiquitin-dependent proteasomal degradation of serine racemase.
        J Biol Chem. 2006; 281: 20291-20302
        • Ma T.M.
        • Paul B.D.
        • Fu C.
        • Hu S.
        • Zhu H.
        • Blackshaw S.
        • et al.
        Serine racemase regulated by binding to stargazin and PSD-95: Potential N-methyl-D-aspartate-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (NMDA-AMPA) glutamate neurotransmission cross-talk.
        J Biol Chem. 2014; 289: 29631-29641
        • Mustafa A.K.
        • van Rossum D.B.
        • Patterson R.L.
        • Maag D.
        • Ehmsen J.T.
        • Gazi S.K.
        • et al.
        Glutamatergic regulation of serine racemase via reversal of PIP2 inhibition.
        Proc Natl Acad Sci U S A. 2009; 106: 2921-2926
        • Gilmartin M.R.
        • Helmstetter F.J.
        Trace and contextual fear conditioning require neural activity and NMDA receptor-dependent transmission in the medial prefrontal cortex.
        Learn Mem. 2010; 17: 289-296
        • Quinn J.J.
        • Loya F.
        • Ma Q.D.
        • Fanselow M.S.
        Dorsal hippocampus NMDA receptors differentially mediate trace and contextual fear conditioning.
        Hippocampus. 2005; 15: 665-674
        • Gilmartin M.R.
        • Kwapis J.L.
        • Helmstetter F.J.
        Trace and contextual fear conditioning are impaired following unilateral microinjection of muscimol in the ventral hippocampus or amygdala, but not the medial prefrontal cortex.
        Neurobiol Learn Mem. 2012; 97: 452-464
        • Guimarais M.
        • Gregorio A.
        • Cruz A.
        • Guyon N.
        • Moita M.A.
        Time determines the neural circuit underlying associative fear learning.
        Front Behav Neurosci. 2011; 5: 89
        • Kwapis J.L.
        • Jarome T.J.
        • Schiff J.C.
        • Helmstetter F.J.
        Memory consolidation in both trace and delay fear conditioning is disrupted by intra-amygdala infusion of the protein synthesis inhibitor anisomycin.
        Learn Mem. 2011; 18: 728-732
        • Kochli D.E.
        • Thompson E.C.
        • Fricke E.A.
        • Postle A.F.
        • Quinn J.J.
        The amygdala is critical for trace, delay, and contextual fear conditioning.
        Learn Mem. 2015; 22: 92-100
        • Matsuda S.
        • Matsuzawa D.
        • Nakazawa K.
        • Sutoh C.
        • Ohtsuka H.
        • Ishii D.
        • et al.
        D-serine enhances extinction of auditory cued fear conditioning via ERK1/2 phosphorylation in mice.
        Prog Neuropsychopharmacol Biol Psychiatry. 2010; 34: 895-902
        • Hammond S.
        • Seymour C.M.
        • Burger A.
        • Wagner J.J.
        D-serine facilitates the effectiveness of extinction to reduce drug-primed reinstatement of cocaine-induced conditioned place preference.
        Neuropharmacology. 2013; 64: 464-471
        • Kvetnansky R.
        • Sabban E.L.
        • Palkovits M.
        Catecholaminergic systems in stress: Structural and molecular genetic approaches.
        Physiol Rev. 2009; 89: 535-606
        • Ishiwata S.
        • Umino A.
        • Balu D.T.
        • Coyle J.T.
        • Nishikawa T.
        Neuronal serine racemase regulates extracellular D-serine levels in the adult mouse hippocampus.
        J Neural Transm. 2015; 122: 1099-1103
        • Chambers R.A.
        • Bremner J.D.
        • Moghaddam B.
        • Southwick S.M.
        • Charney D.S.
        • Krystal J.H.
        Glutamate and post-traumatic stress disorder: Toward a psychobiology of dissociation.
        Semin Clin Neuropsychiatry. 1999; 4: 274-281
        • Attari A.
        • Rajabi F.
        • Maracy M.R.
        D-cycloserine for treatment of numbing and avoidance in chronic post traumatic stress disorder: A randomized, double blind, clinical trial.
        J Res Med Sci. 2014; 19: 592-598
        • Sripada R.K.
        • Garfinkel S.N.
        • Liberzon I.
        Avoidant symptoms in PTSD predict fear circuit activation during multimodal fear extinction.
        Front Hum Neurosci. 2013; 7: 672
        • Wicking M.
        • Steiger F.
        • Nees F.
        • Diener S.J.
        • Grimm O.
        • Ruttorf M.
        • et al.
        Deficient fear extinction memory in posttraumatic stress disorder.
        Neurobiol Learn Mem. 2016; 136: 116-126
        • Ressler K.J.
        • Rothbaum B.O.
        • Tannenbaum L.
        • Anderson P.
        • Graap K.
        • Zimand E.
        • et al.
        Cognitive enhancers as adjuncts to psychotherapy: Use of D-cycloserine in phobic individuals to facilitate extinction of fear.
        Arch Gen Psychiatry. 2004; 61: 1136-1144