@article{ZieglerAlmosMcNeilletal.2020, author = {Ziegler, Georg C. and Almos, Peter and McNeill, Rhiannon V. and Jansch, Charline and Lesch, Klaus-Peter}, title = {Cellular effects and clinical implications of SLC2A3 copy number variation}, series = {Journal of Cellular Physiology}, volume = {235}, journal = {Journal of Cellular Physiology}, number = {12}, doi = {10.1002/jcp.29753}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218009}, pages = {9021 -- 9036}, year = {2020}, abstract = {SLC2A3 encodes the predominantly neuronal glucose transporter 3 (GLUT3), which facilitates diffusion of glucose across plasma membranes. The human brain depends on a steady glucose supply for ATP generation, which consequently fuels critical biochemical processes, such as axonal transport and neurotransmitter release. Besides its role in the central nervous system, GLUT3 is also expressed in nonneural organs, such as the heart and white blood cells, where it is equally involved in energy metabolism. In cancer cells, GLUT3 overexpression contributes to the Warburg effect by answering the cell's increased glycolytic demands. The SLC2A3 gene locus at chromosome 12p13.31 is unstable and prone to non-allelic homologous recombination events, generating multiple copy number variants (CNVs) of SLC2A3 which account for alterations in SLC2A3 expression. Recent associations of SLC2A3 CNVs with different clinical phenotypes warrant investigation of the potential influence of these structural variants on pathomechanisms of neuropsychiatric, cardiovascular, and immune diseases. In this review, we accumulate and discuss the evidence how SLC2A3 gene dosage may exert diverse protective or detrimental effects depending on the pathological condition. Cellular states which lead to increased energetic demand, such as organ development, proliferation, and cellular degeneration, appear particularly susceptible to alterations in SLC2A3 copy number. We conclude that better understanding of the impact of SLC2A3 variation on disease etiology may potentially provide novel therapeutic approaches specifically targeting this GLUT.}, language = {en} } @article{ZayatsJacobsenKleppeetal.2016, author = {Zayats, T and Jacobsen, KK and Kleppe, R and Jacob, CP and Kittel-Schneider, S and Ribas{\´e}s, M and Ramos-Quiroga, JA and Richarte, V and Casas, M and Mota, NR and Grevet, EH and Klein, M and Corominas, J and Bralten, J and Galesloot, T and Vasquez, AA and Herms, S and Forstner, AJ and Larsson, H and Breen, G and Asherson, P and Gross-Lesch, S and Lesch, KP and Cichon, S and Gabrielsen, MB and Holmen, OL and Bau, CHD and Buitelaar, J and Kiemeney, L and Faraone, SV and Cormand, B and Franke, B and Reif, A and Haavik, J and Johansson, S}, title = {Exome chip analyses in adult attention deficit hyperactivity disorder}, series = {Translational Psychiatry}, volume = {6}, journal = {Translational Psychiatry}, number = {e923}, doi = {10.1038/tp.2016.196}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-168297}, year = {2016}, abstract = {Attention-deficit/hyperactivity disorder (ADHD) is a highly heritable childhood-onset neuropsychiatric condition, often persisting into adulthood. The genetic architecture of ADHD, particularly in adults, is largely unknown. We performed an exome-wide scan of adult ADHD using the Illumina Human Exome Bead Chip, which interrogates over 250 000 common and rare variants. Participants were recruited by the International Multicenter persistent ADHD CollaboraTion (IMpACT). Statistical analyses were divided into 3 steps: (1) gene-level analysis of rare variants (minor allele frequency (MAF)<1\%); (2) single marker association tests of common variants (MAF⩾1\%), with replication of the top signals; and (3) pathway analyses. In total, 9365 individuals (1846 cases and 7519 controls) were examined. Replication of the most associated common variants was attempted in 9847 individuals (2077 cases and 7770 controls) using fixed-effects inverse variance meta-analysis. With a Bonferroni-corrected significance level of 1.82E-06, our analyses of rare coding variants revealed four study-wide significant loci: 6q22.1 locus (P=4.46E-08), where NT5DC1 and COL10A1 reside; the SEC23IP locus (P=6.47E-07); the PSD locus (P=7.58E-08) and ZCCHC4 locus (P=1.79E-06). No genome-wide significant association was observed among the common variants. The strongest signal was noted at rs9325032 in PPP2R2B (odds ratio=0.81, P=1.61E-05). Taken together, our data add to the growing evidence of general signal transduction molecules (NT5DC1, PSD, SEC23IP and ZCCHC4) having an important role in the etiology of ADHD. Although the biological implications of these findings need to be further explored, they highlight the possible role of cellular communication as a potential core component in the development of both adult and childhood forms of ADHD.}, language = {en} } @article{WeidnerLardenoijeEijssenetal.2019, author = {Weidner, Magdalena T. and Lardenoije, Roy and Eijssen, Lars and Mogavero, Floriana and De Groodt, Lilian P. M. T. and Popp, Sandy and Palme, Rupert and F{\"o}rstner, Konrad U. and Strekalova, Tatyana and Steinbusch, Harry W. M. and Schmitt-B{\"o}hrer, Angelika G. and Glennon, Jeffrey C. and Waider, Jonas and van den Hove, Daniel L. A. and Lesch, Klaus-Peter}, title = {Identification of cholecystokinin by genome-wide profiling as potential mediator of serotonin-dependent behavioral effects of maternal separation in the amygdala}, series = {Frontiers in Neuroscience}, volume = {13}, journal = {Frontiers in Neuroscience}, doi = {10.3389/fnins.2019.00460}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201340}, pages = {460}, year = {2019}, abstract = {Converging evidence suggests a role of serotonin (5-hydroxytryptamine, 5-HT) and tryptophan hydroxylase 2 (TPH2), the rate-limiting enzyme of 5-HT synthesis in the brain, in modulating long-term, neurobiological effects of early-life adversity. Here, we aimed at further elucidating the molecular mechanisms underlying this interaction, and its consequences for socio-emotional behaviors, with a focus on anxiety and social interaction. In this study, adult, male Tph2 null mutant (Tph2\(^{-/-}\)) and heterozygous (Tph2\(^{+/-}\)) mice, and their wildtype littermates (Tph2\(^{+/+}\)) were exposed to neonatal, maternal separation (MS) and screened for behavioral changes, followed by genome-wide RNA expression and DNA methylation profiling. In Tph2\(^{-/-}\) mice, brain 5-HT deficiency profoundly affected socio-emotional behaviors, i.e., decreased avoidance of the aversive open arms in the elevated plus-maze (EPM) as well as decreased prosocial and increased rule breaking behavior in the resident-intruder test when compared to their wildtype littermates. Tph2\(^{+/-}\) mice showed an ambiguous profile with context-dependent, behavioral responses. In the EPM they showed similar avoidance of the open arm but decreased prosocial and increased rule breaking behavior in the resident-intruder test when compared to their wildtype littermates. Notably, MS effects on behavior were subtle and depended on the Tph2 genotype, in particular increasing the observed avoidance of EPM open arms in wildtype and Tph2\(^{+/-}\) mice when compared to their Tph2\(^{-/-}\) littermates. On the genomic level, the interaction of Tph2 genotype with MS differentially affected the expression of numerous genes, of which a subset showed an overlap with DNA methylation profiles at corresponding loci. Remarkably, changes in methylation nearby and expression of the gene encoding cholecystokinin, which were inversely correlated to each other, were associated with variations in anxiety-related phenotypes. In conclusion, next to various behavioral alterations, we identified gene expression and DNA methylation profiles to be associated with TPH2 inactivation and its interaction with MS, suggesting a gene-by-environment interaction-dependent, modulatory function of brain 5-HT availability.}, language = {en} } @article{WaiderPoppMlinaretal.2019, author = {Waider, Jonas and Popp, Sandy and Mlinar, Boris and Montalbano, Alberto and Bonfiglio, Francesco and Aboagye, Benjamin and Thuy, Elisabeth and Kern, Raphael and Thiel, Christopher and Araragi, Naozumi and Svirin, Evgeniy and Schmitt-B{\"o}hrer, Angelika G. and Corradetti, Renato and Lowry, Christopher A. and Lesch, Klaus-Peter}, title = {Serotonin deficiency increases context-dependent fear learning through modulation of hippocampal activity}, series = {Frontiers in Neuroscience}, volume = {13}, journal = {Frontiers in Neuroscience}, number = {245}, issn = {1662-453X}, doi = {10.3389/fnins.2019.00245}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-196077}, year = {2019}, abstract = {Brain serotonin (5-hydroxytryptamine, 5-HT) system dysfunction is implicated in exaggerated fear responses triggering various anxiety-, stress-, and trauma-related disorders. However, the underlying mechanisms are not well understood. Here, we investigated the impact of constitutively inactivated 5-HT synthesis on context-dependent fear learning and extinction using tryptophan hydroxylase 2 (Tph2) knockout mice. Fear conditioning and context-dependent fear memory extinction paradigms were combined with c-Fos imaging and electrophysiological recordings in the dorsal hippocampus (dHip). Tph2 mutant mice, completely devoid of 5-HT synthesis in brain, displayed accelerated fear memory formation and increased locomotor responses to foot shock. Furthermore, recall of context-dependent fear memory was increased. The behavioral responses were associated with increased c-Fos expression in the dHip and resistance to foot shock-induced impairment of hippocampal long-term potentiation (LTP). In conclusion, increased context-dependent fear memory resulting from brain 5-HT deficiency involves dysfunction of the hippocampal circuitry controlling contextual representation of fear-related behavioral responses.}, language = {en} } @article{WaiderPoppLangeetal.2017, author = {Waider, J and Popp, S and Lange, MD and Kern, R and Kolter, JF and Kobler, J and Donner, NC and Lowe, KR and Malzbender, JH and Brazell, CJ and Arnold, MR and Aboagye, B and Schmitt-B{\"o}hrer, A and Lowry, CA and Pape, HC and Lesch, KP}, title = {Genetically driven brain serotonin deficiency facilitates panic-like escape behavior in mice}, series = {Translational Psychiatry}, volume = {7}, journal = {Translational Psychiatry}, number = {e1246}, doi = {10.1038/tp.2017.209}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170239}, year = {2017}, abstract = {Multiple lines of evidence implicate brain serotonin (5-hydroxytryptamine; 5-HT) system dysfunction in the pathophysiology of stressor-related and anxiety disorders. Here we investigate the influence of constitutively deficient 5-HT synthesis on stressor-related anxiety-like behaviors using Tryptophan hydroxylase 2 (Tph2) mutant mice. Functional assessment of c-Fos after associated foot shock, electrophysiological recordings of GABAergic synaptic transmission, differential expression of the Slc6a4 gene in serotonergic neurons were combined with locomotor and anxiety-like measurements in different contextual settings. Our findings indicate that constitutive Tph2 inactivation and consequential lack of 5-HT synthesis in Tph2 null mutant mice (Tph2\(^{-/-}\)) results in increased freezing to associated foot shock and a differential c-Fos activity pattern in the basolateral complex of the amygdala. This is accompanied by altered GABAergic transmission as observed by recordings of inhibitory postsynaptic currents on principal neurons in the basolateral nucleus, which may explain increased fear associated with hyperlocomotion and escape-like responses in aversive inescapable contexts. In contrast, lifelong 5-HT deficiency as observed in Tph2 heterozygous mice (Tph\(^{+/-}\)) is able to be compensated through reduced GABAergic transmission in the basolateral nucleus of the amygdala based on Slc6a4 mRNA upregulation in subdivisions of dorsal raphe neurons. This results in increased activity of the basolateral nucleus of the amygdala due to associated foot shock. In conclusion, our results reflect characteristic syndromal dimensions of panic disorder and agoraphobia. Thus, constitutive lack of 5-HT synthesis influence the risk for anxiety- and stressor-related disorders including panic disorder and comorbid agoraphobia through the absence of GABAergic-dependent compensatory mechanisms in the basolateral nucleus of the amygdala.}, language = {en} } @article{VeniaminovaCespuglioCheungetal.2017, author = {Veniaminova, Ekaterina and Cespuglio, Raymond and Cheung, Chi Wai and Umriukhin, Alexei and Markova, Nataliia and Shevtsova, Elena and Lesch, Klaus-Peter and Anthony, Daniel C. and Strekalova, Tatyana}, title = {Autism-like behaviours and memory deficits result from a Western Diet in mice}, series = {Neural Plasticity}, journal = {Neural Plasticity}, doi = {10.1155/2017/9498247}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158211}, pages = {9498247}, year = {2017}, abstract = {Nonalcoholic fatty liver disease, induced by a Western diet (WD), evokes central and peripheral inflammation that is accompanied by altered emotionality. These changes can be associated with abnormalities in social behaviour, hippocampus-dependent cognitive functions, and metabolism. Female C57BL/6J mice were fed with a regular chow or with a WD containing 0.2\% of cholesterol and 21\% of saturated fat for three weeks. WD-treated mice exhibited increased social avoidance, crawl-over and digging behaviours, decreased body-body contacts, and hyperlocomotion. The WD-fed group also displayed deficits in hippocampal-dependent performance such as contextual memory in a fear conditioning and pellet displacement paradigms. A reduction in glucose tolerance and elevated levels of serum cholesterol and leptin were also associated with the WD. The peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1a) mRNA, a marker of mitochondrial activity, was decreased in the prefrontal cortex, hippocampus, hypothalamus, and dorsal raphe, suggesting suppressed brain mitochondrial functions, but not in the liver. This is the first report to show that a WD can profoundly suppress social interactions and induce dominant-like behaviours in na{\"i}ve adult mice. The spectrum of behaviours that were found to be induced are reminiscent of symptoms associated with autism, and, if paralleled in humans, suggest that a WD might exacerbate autism spectrum disorder.}, language = {en} } @article{VeniaminovaCespuglioChernukhaetal.2020, author = {Veniaminova, Ekaterina and Cespuglio, Raymond and Chernukha, Irina and Schmitt-Boehrer, Angelika G. and Morozov, Sergey and Kalueff, Allan V. and Kuznetsova, Oxana and Anthony, Daniel C. and Lesch, Klaus-Peter and Strekalova, Tatyana}, title = {Metabolic, Molecular, and Behavioral Effects of Western Diet in Serotonin Transporter-Deficient Mice: Rescue by Heterozygosity?}, series = {Frontiers in Neuroscience}, volume = {14}, journal = {Frontiers in Neuroscience}, issn = {1662-453X}, doi = {10.3389/fnins.2020.00024}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-199813}, year = {2020}, abstract = {Reduced function of the serotonin transporter (SERT) is associated with increased susceptibility to anxiety and depression and with type-2 diabetes, which is especially true in older women. Preference for a "Western diet" (WD), enriched with saturated fat, cholesterol, and sugars, may aggravate these conditions. In previous studies, decreased glucose tolerance, central and peripheral inflammation, dyslipidemia, emotional, cognitive, and social abnormalities were reported in WD-fed young female mice. We investigated the metabolic, molecular, and behavioral changes associated with a 3-week-long dietary regime of either the WD or control diet in 12-month-old female mice with three different Sert genotypes: homozygous (Slc6a4) gene knockout (Sert\(^{-/-}\): KO), heterozygous (Sert\(^{+/-}\): HET), or wild-type mice (Sert\(^{+/+}\): WT). In the WT-WD and KO-WD groups, but not in HET-WD-fed mice, most of changes induced by the WD paralleled those found in the younger mice, including brain overexpression of inflammatory marker Toll-like receptor 4 (Tlr4) and impaired hippocampus-dependent performance in the marble test. However, the 12-month-old female mice became obese. Control diet KO mice exhibited impaired hippocampal-dependent behaviors, increased brain expression of the serotonin receptors Htr2c and Htr1b, as well as increased Tlr4 and mitochondrial regulator, peroxisome proliferator-activated receptor gamma-coactivator-1a (Ppargc1a). Paradoxically, these, and other changes, were reversed in KO-WD mutants, suggesting a complex interplay between Sert deficiency and metabolic factors as well as potential compensatory molecular mechanisms that might be disrupted by the WD exposure. Most, but not all, of the changes in gene expression in the brain and liver of KO mice were not exhibited by the HET mice fed with either diet. Some of the WD-induced changes were similar in the KO-WD and HET-WD-fed mice, but the latter displayed a "rescued" phenotype in terms of diet-induced abnormalities in glucose tolerance, neuroinflammation, and hippocampus-dependent performance. Thus, complete versus partial Sert inactivation in aged mice results in distinct metabolic, molecular, and behavioral consequences in response to the WD. Our findings show that Sert\(^{+/-}\) mice are resilient to certain environmental challenges and support the concept of heterosis as evolutionary adaptive mechanism.}, language = {en} } @article{SvirinVeniaminovaCostaNunesetal.2022, author = {Svirin, Evgeniy and Veniaminova, Ekaterina and Costa-Nunes, Jo{\~a}o Pedro and Gorlova, Anna and Umriukhin, Aleksei and Kalueff, Allan V. and Proshin, Andrey and Anthony, Daniel C. and Nedorubov, Andrey and Tse, Anna Chung Kwan and Walitza, Susanne and Lim, Lee Wei and Lesch, Klaus-Peter and Strekalova, Tatyana}, title = {Predation stress causes excessive aggression in female mice with partial genetic inactivation of tryptophan hydroxylase-2: evidence for altered myelination-related processes}, series = {Cells}, volume = {11}, journal = {Cells}, number = {6}, issn = {2073-4409}, doi = {10.3390/cells11061036}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-267250}, year = {2022}, abstract = {The interaction between brain serotonin (5-HT) deficiency and environmental adversity may predispose females to excessive aggression. Specifically, complete inactivation of the gene encoding tryptophan hydroxylase-2 (Tph2) results in the absence of neuronal 5-HT synthesis and excessive aggressiveness in both male and female null mutant (Tph2\(^{-/-}\)) mice. In heterozygous male mice (Tph2\(^{+/-}\)), there is a moderate reduction in brain 5-HT levels, and when they are exposed to stress, they exhibit increased aggression. Here, we exposed female Tph2\(^{+/-}\) mice to a five-day rat predation stress paradigm and assessed their emotionality and social interaction/aggression-like behaviors. Tph2\(^{+/-}\) females exhibited excessive aggression and increased dominant behavior. Stressed mutants displayed altered gene expression of the 5-HT receptors Htr1a and Htr2a, glycogen synthase kinase-3 β (GSK-3β), and c-fos as well as myelination-related transcripts in the prefrontal cortex: myelin basic protein (Mbp), proteolipid protein 1 (Plp1), myelin-associated glycoprotein (Mag), and myelin oligodendrocyte glycoprotein (Mog). The expression of the plasticity markers synaptophysin (Syp) and cAMP response element binding protein (Creb), but not AMPA receptor subunit A2 (GluA2), were affected by genotype. Moreover, in a separate experiment, na{\"i}ve female Tph2\(^{+/-}\) mice showed signs of enhanced stress resilience in the modified swim test with repeated swimming sessions. Taken together, the combination of a moderate reduction in brain 5-HT with environmental challenges results in behavioral changes in female mice that resemble the aggression-related behavior and resilience seen in stressed male mutants; additionally, the combination is comparable to the phenotype of null mutants lacking neuronal 5-HT. Changes in myelination-associated processes are suspected to underpin the molecular mechanisms leading to aggressive behavior.}, language = {en} } @article{StrekalovaMarkovaShevtsovaetal.2016, author = {Strekalova, Tatyana and Markova, Nataliia and Shevtsova, Elena and Zubareva, Olga and Bakhmet, Anastassia and Steinbusch, Harry M. and Bachurin, Sergey and Lesch, Klaus-Peter}, title = {Individual Differences in Behavioural Despair Predict Brain GSK-3beta Expression in Mice: The Power of a Modified Swim Test}, series = {Neural Plasticity}, volume = {2016}, journal = {Neural Plasticity}, doi = {10.1155/2016/5098591}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-147379}, pages = {5098591}, year = {2016}, abstract = {While deficient brain plasticity is a well-established pathophysiologic feature of depression, little is known about disorder-associated enhanced cognitive processing. Here, we studied a novel mouse paradigm that potentially models augmented learning of adverse memories during development of a depressive-like state. We used a modification of the classic two-day protocol of a mouse Porsolt test with an additional session occurring on Day 5 following the initial exposure. Unexpectedly, floating behaviour and brain glycogen synthase kinase-3 beta (GSK-3beta) mRNA levels, a factor of synaptic plasticity as well as a marker of distress and depression, were increased during the additional swimming session that was prevented by imipramine. Observed increases of GSK-3beta mRNA in prefrontal cortex during delayed testing session correlated with individual parameters of behavioural despair that was not found in the classic Porsolt test. Repeated swim exposure was accompanied by a lower pGSK-3beta/GSK-3beta ratio. A replacement of the second or the final swim sessions with exposure to the context of testing resulted in increased GSK-3beta mRNA level similar to the effects of swimming, while exclusion of the second testing prevented these changes. Together, our findings implicate the activation of brain GSK-3beta expression in enhanced contextual conditioning of adverse memories, which is associated with an individual susceptibility to a depressive syndrome.}, language = {en} } @article{SchaeferFriedrichJorgensenetal.2018, author = {Sch{\"a}fer, Nadine and Friedrich, Maximilian and J{\o}rgensen, Morten Egevang and Kollert, Sina and Koepsell, Hermann and Wischmeyer, Erhard and Lesch, Klaus-Peter and Geiger, Dietmar and D{\"o}ring, Frank}, title = {Functional analysis of a triplet deletion in the gene encoding the sodium glucose transporter 3, a potential risk factor for ADHD}, series = {PLoS ONE}, volume = {13}, journal = {PLoS ONE}, number = {10}, doi = {10.1371/journal.pone.0205109}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176495}, pages = {e0205109}, year = {2018}, abstract = {Sodium-glucose transporters (SGLT) belong to the solute carrier 5 family, which is characterized by sodium dependent transport of sugars and other solutes. In contrast, the human SGLT3 (hSGLT3) isoform, encoded by SLC5A4, acts as a glucose sensor that does not transport sugar but induces membrane depolarization by Na\(^{+}\) currents upon ligand binding. Whole-exome sequencing (WES) of several extended pedigrees with high density of attention-deficit/hyperactivity disorder (ADHD) identified a triplet ATG deletion in SLC5A4 leading to a single amino acid loss (ΔM500) in the hSGLT3 protein imperfectly co-segregating with the clinical phenotype of ADHD. Since mutations in homologous domains of hSGLT1 and hSGLT2 were found to affect intestinal and renal function, respectively, we analyzed the functional properties of hSGLT3[wt] and [ΔM500] by voltage clamp and current clamp recordings from cRNA-injected Xenopus laevis oocytes. The cation conductance of hSGLT3[wt] was activated by application of glucose or the specific agonist 1-desoxynojirimycin (DNJ) as revealed by inward currents in the voltage clamp configuration and cell depolarization in the current clamp mode. Almost no currents and changes in membrane potential were observed when glucose or DNJ were applied to hSGLT3[ΔM500]-injected oocytes, demonstrating a loss of function by this amino acid deletion in hSGLT3. To monitor membrane targeting of wt and mutant hSGLT3, fusion constructs with YFP were generated, heterologously expressed in Xenopus laevis oocytes and analyzed for membrane fluorescence by confocal microscopy. In comparison to hSGLT3[wt] the fluorescent signal of mutant [ΔM500] was reduced by 43\% indicating that the mutant phenotype might mainly result from inaccurate membrane targeting. As revealed by homology modeling, residue M500 is located in TM11 suggesting that in addition to the core structure (TM1-TM10) of the transporter, the surrounding TMs are equally crucial for transport/sensor function. In conclusion, our findings indicate that the deletion [ΔM500] in hSGLT3 inhibits membrane targeting and thus largely disrupts glucose-induced sodium conductance, which may, in interaction with other ADHD risk-related gene variants, influence the risk for ADHD in deletion carriers.}, language = {en} }