Project description:The single nucleotide polymorphism rs13166360, causing a substitution of valine 147 to leucine in the adenylyl cyclase 2 (ADCY2), has previously been associated with bipolar disorder (BD). Here we show that this missense mutation diminishes ADCY2 activity by altering its subcellular localization. Mice homozygous for the leucine variant display signs of a mania-like state accompanied by cognitive impairments. Mutant mice are hypersensitive to amphetamine and mania-like behaviors are responsive to lithium treatment. Exposure to chronic social defeat stress switches homozygous leucine variant carriers from a mania- to a depressive-like state. Single-cell RNA-seq revealed widespread expression of ADCY2 in numerous hippocampal cell types. Differentially expressed genes particularly identified from glutamatergic CA1 neurons point towards ADCY2 variant-dependent alterations in multiple biological processes including cAMP-related signaling pathways. These results validate ADCY2 as a BD risk gene providing insights into underlying disease mechanisms potentially opening novel avenues for therapeutic intervention strategies.
Project description:Bipolar disorder (BD) is a psychiatric disorder in which the core feature is pathological disturbance in mood ranging from extreme elation (mania) to severe depression. Study has shown an aberrant pro-inflammatory status of monocytes/macrophages in mood disorders. Therefore, this study aimed at studying the monocyte compartment in Bipolar Disorder, by transcription profiling of CD14+ monocytes in patients and controls.
Project description:The single nucleotide polymorphism rs13166360, causing a substitution of valine (Val) 147 to leucine (Leu) in the adenylyl cyclase 2 (ADCY2), has previously been associated with bipolar disorder (BD). Here we show that the disease-associated ADCY2 missense mutation diminishes the enzyme´s capacity to generate the second messenger 3',5'-cylic adenosine monophosphate (cAMP) by altering its subcellular localization. We established mice specifically carrying the Val to Leu substitution using CRISPR/Cas9-based gene editing. Mice homozygous for the Leu variant display symptoms of a mania-like state accompanied by cognitive impairments. Mutant animals show additional characteristic signs of rodent mania models, i.e., they are hypersensitive to amphetamine, the observed mania-like behaviors are responsive to lithium treatment and the Val to Leu substitution results in a shifted excitatory/inhibitory synaptic balance towards more excitation. Exposure to chronic social defeat stress switches homozygous Leu variant carriers from a mania- to a depressive-like state, a transition which is reminiscent of the alternations characterizing the symptomatology in BD patients. Single-cell RNA-seq (scRNA-seq) revealed widespread Adcy2 mRNA expression in numerous hippocampal cell types. Differentially expressed genes particularly identified from glutamatergic CA1 neurons point towards ADCY2 variant-dependent alterations in multiple biological processes including cAMP-related signaling pathways. These results validate ADCY2 as a BD risk gene, provide insights into underlying disease mechanisms, and potentially open novel avenues for therapeutic intervention strategies.
Project description:The aim of this experiment was to absolutely quantify adenylyl cyclase 8 (AC8) and the co-purified interactor calmodulin (CaM) to assess their stoichiometry.
Project description:Mice with the two calcium-stmulated adenylyl cyclase isoforms (AC1 and AC8; DKO mice) knocked-out show conditioned fear memory deficits. We assessed gene expression changes at baseline and several time points after conditioned fear learning to assess transcriptional changes at different stages of learning. Transcriptional changes were assessed in the amydgdala and hippocampus of DKO and wild-type mice.
Project description:Bipolar disorder (BD) is a highly heritable and heterogeneous mental illness whose manifestations often include impulsive and risk-taking behavior. This particular phenotype suggests that abnormal striatal function could be involved in BD etiology, yet most transcriptomic studies of this disorder have concentrated on cortical brain regions. We report the first transcriptome profiling by RNA-Seq of the human dorsal striatum comparing bipolar and control subjects. Differential expression analysis and functional pathway enrichment analysis were performed to identify changes in gene expression that correlate with BD status. Further co-expression and enrichment analyses were performed to identify sets of correlated genes that show association to BD. Total RNA samples were isolated from 36 postmortem dorsal striatum subjects (18 bipolar and 18 control) and sequenced. One outlier sample was removed and 35 samples (18 bipolar and 17 control) were analyzed.
Project description:Bipolar Disorder (BD) is a complex neuropsychiatric disorder that is characterized by intermittent episodes of mania and depression and, without treatment, 15% of patients commit suicide1. Hence, among all diseases, BD has been ranked by the WHO as a top disorder of morbidity and lost productivity2. Previous neuropathological studies have revealed a series of alterations in the brains of BD patients or animal models3, such as reduced glial cell number in the patient prefrontal cortex4, up-regulated activities of the PKA/PKC pathways5-7, and changes in dopamine/5-HT/glutamate neurotransmission systems8-11. However, the roles and causation of these changes in BD are too complex to exactly determine the pathology of the disease; none of the current BD animal models can recapitulate both the manic and depressive phenotypes or spontaneous cycling of BD simultaneously12,13. Furthermore, while some patients show remarkable improvement with lithium treatment, for yet unknown reasons, other patients are refractory to lithium treatment. Therefore, developing an accurate and powerful biological model has been a challenge for research into BD. The development of induced pluripotent stem cell (iPSC) technology has provided such a new approach. Here, we developed a human BD iPSC model and investigated the cellular phenotypes of hippocampal dentate gyrus neurons derived from the patient iPSCs. Using patch clamp recording, somatic Ca2+ imaging and RNA-seq techniques, we found that the neurons derived from BD patients exhibited hyperactive action potential (AP) firing, up-regulated expression of PKA/PKC/AP and mitochondria-related genes. Moreover, lithium selectively reversed these alterations in the neurons of patients who responded to lithium treatment. Therefore, hyper-excitability is one endophenotype of BD that is probably achieved through enhancement in the PKA/PKC and Na+ channel signaling systems, and our BD iPSC model can be used to develop new therapies and drugs aimed at clinical treatment of this disease. total RNAseq from neurons generated from BD patient-specific iPS cells
Project description:Analysis of gene-expression changes in depressed subjects with bipolar disorder compared to healthy controls. Results provide information on pathways that may be involved in the pathogenesis of bipolar depression. Total RNA isolated from PAXgene blood RNA tubes from 20 depressed subjects with bipolar disorder and 15 healthy controls.
Project description:Bipolar disorder is a complex polygenetic disorder that is characterized by recurrent episodes of depression and mania, the heterogeneity of which is likely complicated by epigenetic modifications that remain to be elucidated. Here, we performed transcriptomic analysis of peripheral blood RNA from monozygotic twins discordant for bipolar disorder and identified a bipolar disorder-associated upregulated long non-coding RNA (lncRNA), AP1AR-DT. We observed that overexpression of AP1AR-DT in the mouse medial prefrontal cortex (mPFC) resulted in a reduction of both the total spine density and the spontaneous excitatory postsynaptic current (sEPSC) frequency of mPFC neurons, as well as depressive and anxiety-like behaviors. A combination of the results of brain transcriptome analysis of AP1AR-DT overexpressing mice brains with the known genes associated with bipolar disorder revealed that NEGR1, which encodes neuronal growth regulator 1, is one of the AP1AR-DT targets and is reduced in vivo upon gain of AP1AR-DT in mice. The results of the present study demonstrated that overexpression of recombinant Negr1 in the mPFC neurons of AP1AR-DTOE mice ameliorates depressive and anxiety-like behaviors and normalizes the reduced excitatory synaptic transmission induced by the gain of AP1AR-DT. Furthermore, the study provides evidence that AP1AR-DT reduces NEGR1 expression by competing for the transcriptional activator NRF1 in the overlapping binding site of the NEGR1 promoter region. The epigenetic and pathophysiological mechanism linking AP1AR-DT to the modulation of excitatory synaptic function provides etiological implications for bipolar disorder.