TY - JOUR AB - P-Glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2) are two efflux transporters at the blood–brain barrier (BBB), which effectively restrict brain distribution of diverse drugs, such as tyrosine kinase inhibitors. There is a crucial need for pharmacological ABCB1 and ABCG2 inhibition protocols for a more effective treatment of brain diseases. In the present study, seven marketed drugs (osimertinib, erlotinib, nilotinib, imatinib, lapatinib, pazopanib, and cyclosporine A) and one nonmarketed drug (tariquidar), with known in vitro ABCB1/ABCG2 inhibitory properties, were screened for their inhibitory potency at the BBB in vivo. Positron emission tomography (PET) using the model ABCB1/ABCG2 substrate [11C]erlotinib was performed in mice. Tested inhibitors were administered as i.v. bolus injections at 30 min before the start of the PET scan, followed by a continuous i.v. infusion for the duration of the PET scan. Five of the tested drugs increased total distribution volume of [11C]erlotinib in the brain (VT,brain) compared to vehicle-treated animals (tariquidar, + 69%; erlotinib, + 19% and +23% for the 21.5 mg/kg and the 43 mg/kg dose, respectively; imatinib, + 22%; lapatinib, + 25%; and cyclosporine A, + 49%). For all drugs, increases in [11C]erlotinib brain distribution were lower than in Abcb1a/b(−/−)Abcg2(−/−) mice (+149%), which suggested that only partial ABCB1/ABCG2 inhibition was reached at the mouse BBB. The plasma concentrations of the tested drugs at the time of the PET scan were higher than clinically achievable plasma concentrations. Some of the tested drugs led to significant increases in blood radioactivity concentrations measured at the end of the PET scan (erlotinib, + 103% and +113% for the 21.5 mg/kg and the 43 mg/kg dose, respectively; imatinib, + 125%; and cyclosporine A, + 101%), which was most likely caused by decreased hepatobiliary excretion of radioactivity. Taken together, our data suggest that some marketed tyrosine kinase inhibitors may be repurposed to inhibit ABCB1 and ABCG2 at the BBB. From a clinical perspective, moderate increases in brain delivery despite the administration of high i.v. doses as well as peripheral drug–drug interactions due to transporter inhibition in clearance organs question the translatability of this concept. AU - Traxl, Alexander AU - Mairinger, Severin AU - Filip, Thomas AU - Sauberer, Michael AU - Stanek, Johann AU - Poschner, Stefan AU - Jäger, Walter AU - Zoufal, Viktoria AU - Novarino, Gaia AU - Tournier, Nicolas AU - Bauer, Martin AU - Wanek, Thomas AU - Langer, Oliver ID - 6088 IS - 3 JF - Molecular Pharmaceutics TI - Inhibition of ABCB1 and ABCG2 at the mouse blood-brain barrier with marketed drugs to improve brain delivery of the model ABCB1/ABCG2 substrate [11C]erlotinib VL - 16 ER - TY - JOUR AB - Investigating neuronal activity using genetically encoded Ca2+ indicators in behaving animals is hampered by inaccuracies in spike inference from fluorescent tracers. Here we combine two‐photon [Ca2+] imaging with cell‐attached recordings, followed by post hoc determination of the expression level of GCaMP6f, to explore how it affects the amplitude, kinetics and temporal summation of somatic [Ca2+] transients in mouse hippocampal pyramidal cells (PCs). The amplitude of unitary [Ca2+] transients (evoked by a single action potential) negatively correlates with GCaMP6f expression, but displays large variability even among PCs with similarly low expression levels. The summation of fluorescence signals is frequency‐dependent, supralinear and also shows remarkable cell‐to‐cell variability. We performed experimental data‐based simulations and found that spike inference error rates using MLspike depend strongly on unitary peak amplitudes and GCaMP6f expression levels. We provide simple methods for estimating the unitary [Ca2+] transients in individual weakly GCaMP6f‐expressing PCs, with which we achieve spike inference error rates of ∼5%. AU - Éltes, Tímea AU - Szoboszlay, Miklos AU - Szigeti, Margit Katalin AU - Nusser, Zoltan ID - 6470 IS - 11 JF - Journal of Physiology SN - 00223751 TI - Improved spike inference accuracy by estimating the peak amplitude of unitary [Ca2+] transients in weakly GCaMP6f-expressing hippocampal pyramidal cells VL - 597 ER - TY - JOUR AB - Until recently, a great amount of brain studies have been conducted in human post mortem tissues, cell lines and model organisms. These researches provided useful insights regarding cell-cell interactions occurring in the brain. However, such approaches suffer from technical limitations and inaccurate modeling of the tissue 3D cytoarchitecture. Importantly, they might lack a human genetic background essential for disease modeling. With the development of protocols to generate human cerebral organoids, we are now closer to reproducing the early stages of human brain development in vitro. As a result, more relevant cell-cell interaction studies can be conducted. In this review, we discuss the advantages of 3D cultures over 2D in modulating brain cell-cell interactions during physiological and pathological development, as well as the progress made in developing organoids in which neurons, macroglia, microglia and vascularization are present. Finally, we debate the limitations of those models and possible future directions. AU - Oliveira, Bárbara AU - Yahya, Aysan Çerağ AU - Novarino, Gaia ID - 6896 JF - Brain Research SN - 00068993 TI - Modeling cell-cell interactions in the brain using cerebral organoids VL - 1724 ER - TY - JOUR AU - Morandell, Jasmin AU - Nicolas, Armel AU - Schwarz, Lena A AU - Novarino, Gaia ID - 7415 IS - Supplement 6 JF - European Neuropsychopharmacology SN - 0924-977X TI - S.16.05 Illuminating the role of the e3 ubiquitin ligase cullin3 in brain development and autism VL - 29 ER - TY - JOUR AU - Knaus, Lisa AU - Tarlungeanu, Dora-Clara AU - Novarino, Gaia ID - 7414 IS - Supplement 6 JF - European Neuropsychopharmacology SN - 0924-977X TI - S.16.03 A homozygous missense mutation in SLC7A5 leads to autism spectrum disorder and microcephaly VL - 29 ER - TY - JOUR AB - Inhibition of the endoplasmic reticulum stress pathway may hold the key to Zika virus-associated microcephaly treatment. AU - Novarino, Gaia ID - 456 IS - 423 JF - Science Translational Medicine TI - Zika-associated microcephaly: Reduce the stress and race for the treatment VL - 10 ER - TY - JOUR AB - Despite the remarkable number of scientific breakthroughs of the last 100 years, the treatment of neurodevelopmental disorders (e.g., autism spectrum disorder, intellectual disability) remains a great challenge. Recent advancements in genomics, such as whole-exome or whole-genome sequencing, have enabled scientists to identify numerous mutations underlying neurodevelopmental disorders. Given the few hundred risk genes that have been discovered, the etiological variability and the heterogeneous clinical presentation, the need for genotype — along with phenotype- based diagnosis of individual patients has become a requisite. In this review we look at recent advancements in genomic analysis and their translation into clinical practice. AU - Tarlungeanu, Dora-Clara AU - Novarino, Gaia ID - 5888 IS - 8 JF - Experimental & Molecular Medicine SN - 2092-6413 TI - Genomics in neurodevelopmental disorders: an avenue to personalized medicine VL - 50 ER - TY - JOUR AB - The precise control of neural stem cell (NSC) proliferation and differentiation is crucial for the development and function of the human brain. Here, we review the emerging links between the alteration of embryonic and adult neurogenesis and the etiology of neuropsychiatric disorders (NPDs) such as autism spectrum disorders (ASDs) and schizophrenia (SCZ), as well as the advances in stem cell-based modeling and the novel therapeutic targets derived from these studies. AU - Sacco, Roberto AU - Cacci, Emanuele AU - Novarino, Gaia ID - 546 IS - 2 JF - Current Opinion in Neurobiology TI - Neural stem cells in neuropsychiatric disorders VL - 48 ER - TY - JOUR AB - Background: Transport protein particle (TRAPP) is a multisubunit complex that regulates membrane trafficking through the Golgi apparatus. The clinical phenotype associated with mutations in various TRAPP subunits has allowed elucidation of their functions in specific tissues. The role of some subunits in human disease, however, has not been fully established, and their functions remain uncertain. Objective: We aimed to expand the range of neurodevelopmental disorders associated with mutations in TRAPP subunits by exome sequencing of consanguineous families. Methods: Linkage and homozygosity mapping and candidate gene analysis were used to identify homozygous mutations in families. Patient fibroblasts were used to study splicing defect and zebrafish to model the disease. Results: We identified six individuals from three unrelated families with a founder homozygous splice mutation in TRAPPC6B, encoding a core subunit of the complex TRAPP I. Patients manifested a neurodevelopmental disorder characterised by microcephaly, epilepsy and autistic features, and showed splicing defect. Zebrafish trappc6b morphants replicated the human phenotype, displaying decreased head size and neuronal hyperexcitability, leading to a lower seizure threshold. Conclusion: This study provides clinical and functional evidence of the role of TRAPPC6B in brain development and function. AU - Marin Valencia, Isaac AU - Novarino, Gaia AU - Johansen, Anide AU - Rosti, Başak AU - Issa, Mahmoud AU - Musaev, Damir AU - Bhat, Gifty AU - Scott, Eric AU - Silhavy, Jennifer AU - Stanley, Valentina AU - Rosti, Rasim AU - Gleeson, Jeremy AU - Imam, Farhad AU - Zaki, Maha AU - Gleeson, Joseph ID - 691 IS - 1 JF - Journal of Medical Genetics SN - 0022-2593 TI - A homozygous founder mutation in TRAPPC6B associates with a neurodevelopmental disorder characterised by microcephaly epilepsy and autistic features VL - 55 ER - TY - THES AB - Autism spectrum disorders (ASD) are a group of genetic disorders often overlapping with other neurological conditions. Despite the remarkable number of scientific breakthroughs of the last 100 years, the treatment of neurodevelopmental disorders (e.g. autism spectrum disorder, intellectual disability, epilepsy) remains a great challenge. Recent advancements in geno mics, like whole-exome or whole-genome sequencing, have enabled scientists to identify numerous mutations underlying neurodevelopmental disorders. Given the few hundred risk genes that were discovered, the etiological variability and the heterogeneous phenotypic outcomes, the need for genotype -along with phenotype- based diagnosis of individual patients becomes a requisite. Driven by this rationale, in a previous study our group described mutations, identified via whole - exome sequencing, in the gene BCKDK – encoding for a key regulator of branched chain amin o acid (BCAA) catabolism - as a cause of ASD. Following up on the role of BCAAs, in the study described here we show that the solute carrier transporter 7a5 (SLC7A5), a large neutral amino acid transporter localized mainly at the blood brain barrier (BBB), has an essential role in maintaining normal levels of brain BCAAs. In mice, deletion of Slc7a5 from the endothelial cells of the BBB leads to atypical brain amino acid profile, abnormal mRNA translation and severe neurolo gical abnormalities. Additionally, deletion of Slc7a5 from the neural progenitor cell population leads to microcephaly. Interestingly, we demonstrate that BCAA intracerebroventricular administration ameliorates abnormal behaviors in adult mutant mice. Furthermore, whole - exome sequencing of patients diagnosed with neurological dis o r ders helped us identify several patients with autistic traits, microcephaly and motor delay carrying deleterious homozygous mutations in the SLC7A5 gene. In conclusion, our data elucidate a neurological syndrome defined by SLC7A5 mutations and support an essential role for t he BCAA s in human bra in function. Together with r ecent studies (described in chapter two) that have successfully made the transition into clinical practice, our findings on the role of B CAAs might have a crucial impact on the development of novel individualized therapeutic strategies for ASD. AU - Tarlungeanu, Dora-Clara ID - 395 SN - 2663-337X TI - The branched chain amino acids in autism spectrum disorders ER - TY - JOUR AB - SETD5 gene mutations have been identified as a frequent cause of idiopathic intellectual disability. Here we show that Setd5-haploinsufficient mice present developmental defects such as abnormal brain-to-body weight ratios and neural crest defect-associated phenotypes. Furthermore, Setd5-mutant mice show impairments in cognitive tasks, enhanced long-term potentiation, delayed ontogenetic profile of ultrasonic vocalization, and behavioral inflexibility. Behavioral issues are accompanied by abnormal expression of postsynaptic density proteins previously associated with cognition. Our data additionally indicate that Setd5 regulates RNA polymerase II dynamics and gene transcription via its interaction with the Hdac3 and Paf1 complexes, findings potentially explaining the gene expression defects observed in Setd5-haploinsufficient mice. Our results emphasize the decisive role of Setd5 in a biological pathway found to be disrupted in humans with intellectual disability and autism spectrum disorder. AU - Deliu, Elena AU - Arecco, Niccoló AU - Morandell, Jasmin AU - Dotter, Christoph AU - Contreras, Ximena AU - Girardot, Charles AU - Käsper, Eva AU - Kozlova, Alena AU - Kishi, Kasumi AU - Chiaradia, Ilaria AU - Noh, Kyung AU - Novarino, Gaia ID - 3 IS - 12 JF - Nature Neuroscience TI - Haploinsufficiency of the intellectual disability gene SETD5 disturbs developmental gene expression and cognition VL - 21 ER - TY - JOUR AB - RNA-dependent RNA polymerases (RdRps) play a key role in the life cycle of RNA viruses and impact their immunobiology. The arenavirus lymphocytic choriomeningitis virus (LCMV) strain Clone 13 provides a benchmark model for studying chronic infection. A major genetic determinant for its ability to persist maps to a single amino acid exchange in the viral L protein, which exhibits RdRp activity, yet its functional consequences remain elusive. To unravel the L protein interactions with the host proteome, we engineered infectious L protein-tagged LCMV virions by reverse genetics. A subsequent mass-spectrometric analysis of L protein pulldowns from infected human cells revealed a comprehensive network of interacting host proteins. The obtained LCMV L protein interactome was bioinformatically integrated with known host protein interactors of RdRps from other RNA viruses, emphasizing interconnected modules of human proteins. Functional characterization of selected interactors highlighted proviral (DDX3X) as well as antiviral (NKRF, TRIM21) host factors. To corroborate these findings, we infected Trim21-/-mice with LCMV and found impaired virus control in chronic infection. These results provide insights into the complex interactions of the arenavirus LCMV and other viral RdRps with the host proteome and contribute to a better molecular understanding of how chronic viruses interact with their host. AU - Khamina, Kseniya AU - Lercher, Alexander AU - Caldera, Michael AU - Schliehe, Christopher AU - Vilagos, Bojan AU - Sahin, Mehmet AU - Kosack, Lindsay AU - Bhattacharya, Anannya AU - Májek, Peter AU - Stukalov, Alexey AU - Sacco, Roberto AU - James, Leo AU - Pinschewer, Daniel AU - Bennett, Keiryn AU - Menche, Jörg AU - Bergthaler, Andreas ID - 540 IS - 12 JF - PLoS Pathogens SN - 15537366 TI - Characterization of host proteins interacting with the lymphocytic choriomeningitis virus L protein VL - 13 ER - TY - CHAP AB - Genetic factors might be largely responsible for the development of autism spectrum disorder (ASD) that alone or in combination with specific environmental risk factors trigger the pathology. Multiple mutations identified in ASD patients that impair synaptic function in the central nervous system are well studied in animal models. How these mutations might interact with other risk factors is not fully understood though. Additionally, how systems outside of the brain are altered in the context of ASD is an emerging area of research. Extracerebral influences on the physiology could begin in utero and contribute to changes in the brain and in the development of other body systems and further lead to epigenetic changes. Therefore, multiple recent studies have aimed at elucidating the role of gene-environment interactions in ASD. Here we provide an overview on the extracerebral systems that might play an important associative role in ASD and review evidence regarding the potential roles of inflammation, trace metals, metabolism, genetic susceptibility, enteric nervous system function and the microbiota of the gastrointestinal (GI) tract on the development of endophenotypes in animal models of ASD. By influencing environmental conditions, it might be possible to reduce or limit the severity of ASD pathology. AU - Hill Yardin, Elisa AU - Mckeown, Sonja AU - Novarino, Gaia AU - Grabrucker, Andreas ED - Schmeisser, Michael ED - Boekers, Tobias ID - 623 SN - 03015556 T2 - Translational Anatomy and Cell Biology of Autism Spectrum Disorder TI - Extracerebral dysfunction in animal models of autism spectrum disorder VL - 224 ER - TY - CHAP AB - As autism spectrum disorder (ASD) is largely regarded as a neurodevelopmental condition, long-time consensus was that its hallmark features are irreversible. However, several studies from recent years using defined mouse models of ASD have provided clear evidence that in mice neurobiological and behavioural alterations can be ameliorated or even reversed by genetic restoration or pharmacological treatment either before or after symptom onset. Here, we review findings on genetic and pharmacological reversibility of phenotypes in mouse models of ASD. Our review should give a comprehensive overview on both aspects and encourage future studies to better understand the underlying molecular mechanisms that might be translatable from animals to humans. AU - Schroeder, Jan AU - Deliu, Elena AU - Novarino, Gaia AU - Schmeisser, Michael ED - Schmeisser, Michael ED - Boekers, Tobias ID - 634 T2 - Translational Anatomy and Cell Biology of Autism Spectrum Disorder TI - Genetic and pharmacological reversibility of phenotypes in mouse models of autism spectrum disorder VL - 224 ER - TY - JOUR AB - Human neurons transplanted into a mouse model for Alzheimer’s disease show human-specific vulnerability to β-amyloid plaques and may help to identify new therapeutic targets. AU - Novarino, Gaia ID - 656 IS - 381 JF - Science Translational Medicine SN - 19466234 TI - Modeling Alzheimer's disease in mice with human neurons VL - 9 ER - TY - JOUR AB - Perinatal exposure to penicillin may result in longlasting gut and behavioral changes. AU - Novarino, Gaia ID - 667 IS - 387 JF - Science Translational Medicine SN - 19466234 TI - The antisocial side of antibiotics VL - 9 ER - TY - JOUR AB - Rett syndrome modeling in monkey mirrors the human disorder. AU - Novarino, Gaia ID - 689 IS - 393 JF - Science Translational Medicine SN - 19466234 TI - Rett syndrome modeling goes simian VL - 9 ER - TY - JOUR AB - Leading autism-associated mutation in mouse partially mimics human disorder. AU - Novarino, Gaia ID - 702 IS - 399 JF - Science Translational Medicine SN - 19466234 TI - The riddle of CHD8 haploinsufficiency in autism spectrum disorder VL - 9 ER - TY - JOUR AB - To determine the dynamics of allelic-specific expression during mouse development, we analyzed RNA-seq data from 23 F1 tissues from different developmental stages, including 19 female tissues allowing X chromosome inactivation (XCI) escapers to also be detected. We demonstrate that allelic expression arising from genetic or epigenetic differences is highly tissue-specific. We find that tissue-specific strain-biased gene expression may be regulated by tissue-specific enhancers or by post-transcriptional differences in stability between the alleles. We also find that escape from X-inactivation is tissue-specific, with leg muscle showing an unexpectedly high rate of XCI escapers. By surveying a range of tissues during development, and performing extensive validation, we are able to provide a high confidence list of mouse imprinted genes including 18 novel genes. This shows that cluster size varies dynamically during development and can be substantially larger than previously thought, with the Igf2r cluster extending over 10 Mb in placenta. AU - Andergassen, Daniel AU - Dotter, Christoph AU - Wenzel, Dyniel AU - Sigl, Verena AU - Bammer, Philipp AU - Muckenhuber, Markus AU - Mayer, Daniela AU - Kulinski, Tomasz AU - Theussl, Hans AU - Penninger, Josef AU - Bock, Christoph AU - Barlow, Denise AU - Pauler, Florian AU - Hudson, Quanah ID - 713 JF - eLife SN - 2050084X TI - Mapping the mouse Allelome reveals tissue specific regulation of allelic expression VL - 6 ER - TY - JOUR AB - Background HIV-1 infection and drug abuse are frequently co-morbid and their association greatly increases the severity of HIV-1-induced neuropathology. While nucleus accumbens (NAcc) function is severely perturbed by drugs of abuse, little is known about how HIV-1 infection affects NAcc. Methods We used calcium and voltage imaging to investigate the effect of HIV-1 trans-activator of transcription (Tat) on rat NAcc. Based on previous neuronal studies, we hypothesized that Tat modulates intracellular Ca2+ homeostasis of NAcc neurons. Results We provide evidence that Tat triggers a Ca2+ signaling cascade in NAcc medium spiny neurons (MSN) expressing D1-like dopamine receptors leading to neuronal depolarization. Firstly, Tat induced inositol 1,4,5-trisphsophate (IP3) receptor-mediated Ca2+ release from endoplasmic reticulum, followed by Ca2+ and Na+ influx via transient receptor potential canonical channels. The influx of cations depolarizes the membrane promoting additional Ca2+ entry through voltage-gated P/Q-type Ca2+ channels and opening of tetrodotoxin-sensitive Na+ channels. By activating this mechanism, Tat elicits a feed-forward depolarization increasing the excitability of D1-phosphatidylinositol-linked NAcc MSN. We previously found that cocaine targets NAcc neurons directly (independent of the inhibition of dopamine transporter) only when IP3-generating mechanisms are concomitantly initiated. When tested here, cocaine produced a dose-dependent potentiation of the effect of Tat on cytosolic Ca2+. Conclusion We describe for the first time a HIV-1 Tat-triggered Ca2+ signaling in MSN of NAcc involving TRPC and depolarization and a potentiation of the effect of Tat by cocaine, which may be relevant for the reward axis in cocaine-abusing HIV-1-positive patients. AU - Brailoiu, Gabriela AU - Deliu, Elena AU - Barr, Jeffrey AU - Console Bram, Linda AU - Ciuciu, Alexandra AU - Abood, Mary AU - Unterwald, Ellen AU - Brǎiloiu, Eugen ID - 714 JF - Drug and Alcohol Dependence SN - 03768716 TI - HIV Tat excites D1 receptor-like expressing neurons from rat nucleus accumbens VL - 178 ER -