Project description:Major depressive disorder (MDD) is a prevalent and life-threatening illness in modern society. The susceptibility to MDD is profoundly influenced by environmental factors, such as stressful lifestyle or traumatic events, which could impose maladaptive transcriptional program through epigenetic regulation. However, the underlying molecular mechanisms remain elusive. Here we report that stress-susceptible rodents exhibit lower levels of histone crotonylation in the medial prefrontal cortex (mPFC), concurrent with regional upregulation of chromodomain Y-like (CDYL), a crotonyl-CoA hydratase and histone methyllysine reader. Overexpression of CDYL in the prelimbic cortex (PL), a sub-region of mPFC, increases microdefeat-induced social avoidance behaviors and anhedonia in mice. Conversely, knockdown of CDYL in PL prevents chronic social defeat stress-induced depression-like behaviors. Mechanistically, we show that CDYL inhibits structural synaptic plasticity mainly by transcriptional repression of neuropeptide VGF, and this activity is dependent on its dual effect on regional histone crotonylation and H3K27 tri-methylation on the VGF promoter. Together, our data indicate CDYL plays a critical role in regulating stress-induced depression-like behaviors, providing a potential therapeutic target for MDD.
Project description:Neuropathic pain (NP) is a complex, chronic pain condition caused by injury or dysfunction affecting the somatosensory nervous system. This study aimed to identify crucial miRNA in prelimbic cortex (PL) involved in NP rats. miRNA microarrays were applied in the present study.
Project description:Neuropathic pain (NP) is a complex, chronic pain condition caused by injury or dysfunction affecting the somatosensory nervous system. This study aimed to identify crucial mRNA in prelimbic cortex (PL) involved in NP rats. mRNA microarrays were applied in the present study.
Project description:Posttraumatic stress disorder (PTSD) is a prevalent psychiatric disorder. Several studies have attempted to characterize molecular alterations associated with PTSD, but most findings were limited to the investigation of specific cellular markers in the periphery or defined brain regions. In the current study, we aimed to unravel affected molecular pathways/mechanisms in the fear circuitry associated with PTSD. We interrogated a foot shock induced-PTSD mouse model by integrating proteomics and metabolomics profiling data. Alterations at the proteome level were analyzed using in vivo 15N metabolic labeling combined with mass spectrometry in prelimbic cortex (PrL), anterior cingulate cortex (ACC), basolateral amygdala (BLA), central nucleus of amygdala (CeA) and CA1 of hippocampus between shocked and non-shocked (control) mice, with and without fluoxetine treatment.
Project description:A fundamental, evolutionarily conserved biological mechanism required for long-term memory formation is rapid induction of gene transcription upon learning in relevant brain areas. For episodic types of memories, two regions undergoing this transcription are the dorsal hippocampus (dHC) and prelimbic (PL) cortex. Whether and to what extent these regions regulate similar or distinct transcriptomic profiles upon learning remains to be understood. Here, we used RNA sequencing in the dHC and PL cortex of male rats to profile their transcriptomes in untrained conditions (baseline) and at 1 hour and 6 days after inhibitory avoidance learning. We found that, out of 33,713 transcripts, over 14,000 were significantly expressed at baseline in both regions and approximately 3,000 were selectively enriched in each region. Gene Ontology biological pathway analyses indicated that commonly expressed pathways included synapse organization, regulation of membrane potential, and vesicle localization. The enriched pathways in the dHC were gliogenesis, axon development, and lipid modification, while in the PL cortex included vesicle localization and synaptic vesicle cycle. At 1 hour after learning, 135 transcripts changed significantly in the dHC and 478 in the PL cortex; of these, only 34 were shared. Biological pathways most significantly regulated by learning in the dHC were protein dephosphorylation, glycogen and glucan metabolism, while in the PL cortex were axon development and axonogenesis. The transcriptome profiles returned to baseline by 6 days after training. Thus, a significant portion of dHC and PL cortex transcriptomic profiles is divergent and their regulation upon learning is largely distinct and transient.
Project description:Time dependent coordinated hippocampal-prefrontal cortical interactions are required for the long-term storage of memories. However, the role of prefrontal cortex (PFC) in encoding of long-term memories remains elusive. Here, we discover a critical role of PFC in the encoding of contextual memories in mice. We demonstrate that specific pools of mRNAs are translated in the PFC following one and six hours of behavioral training. Moreover, disruption of protein synthesis in the prelimbic region of PFC immediately after training inhibits encoding contextual fear memories, whereas disruption at six hours after training is ineffective. Thus, early protein synthesis in the PFC is necessary and critical for the encoding of contextual fear memories. These findings establish key role for the prelimbic cortex in encoding of contextual memories.
Project description:Translational profiling of prelimbic cortical projections to nucleus accumbens, basolateral amygdala, and ventral tegmental area was performed. Studies were performed using AAV5-IV-GFPL10 (in prelimbic cortex) in tandem with CAV2-Cre (in the projection target), which enables rapid, projection-specific translational profiling.
Project description:Posttraumatic stress disorder (PTSD) is a prevalent psychiatric disorder. Several studies have attempted to characterize molecular alterations associated with PTSD, but most findings were limited to the investigation of specific cellular markers in the periphery or defined brain regions. In the current study, we aimed to unravel affected molecular pathways/mechanisms in the fear circuitry associated with PTSD. We interrogated a foot shock induced PTSD mouse model by integrating proteomics and metabolomics profiling data. Alterations at the proteome level were analyzed using in vivo 15N metabolic labeling combined with mass spectrometry in prelimbic cortex (PrL), anterior cingulate cortex (ACC), basolateral amygdala (BLA), central nucleus of amygdala (CeA) and CA1 of hippocampus between shocked and non-shocked (control) mice, with and without fluoxetine treatment.
Project description:The suppression of fear memory in the absence of danger (fear extinction) requires coordinated neural activity within the amygdala and medial prefrontal (prelimbic and infralimbic) cortex. Any behavior has a transcriptomic signature that is modified by environmental experiences, and specific genes are involved in functional plasticity and synaptic wiring during fear memory and extinction. In the present study, we investigated the effects of optogenetic manipulations of prelimbic pyramidal neurons on amygdala gene expression to analyze the specific transcriptional pathways involved in fear extinction. To this aim, transgenic mice (Thy1-COP4) having cortical and amygdala pyramidal neurons optogenetically excitable were (or not) fear-conditioned. During the extinction phase, the mice received optogenetic (or sham) stimulations to maintain the activation of the prelimbic pyramidal neurons and impair fear extinction. At the end of behavioral testing, electrophysiological (Excitatory Post-Synaptic Currents) and morphological (spinogenesis) correlates were evaluated in the pyramidal neurons of prelimbic cortex. Furthermore, transcriptomic cell-specific RNA-analyses (differential gene expression profiling and functional enrichment analyses) were performed in amygdala pyramidal neurons. Results demonstrate that pyramidal neurons of prelimbic cortex are involved in modulation of the fear responses during extinction phase and their optogenetic stimulation in fear-conditioned mice results in strong modifications of the amygdala transcriptome. Understanding the transcriptomic architecture of fear extinction may facilitate the comprehension of fear-related disorders.
Project description:Previous work has led us to examine the differences in the choroid plexus function in B10.pl WT mice versus B10.PL RAG-/- mice. We believe that there is a difference between those that are normal functioning and those that are lymphocyte deficient. To determine the gene expression profile of the choroid plexus in wild type mice as compared to those that are lymphocyte deficient. We hypothesize that there is altered expression in the genes that mediate cellular adhesion in choroid plexus from wild type mice as compared to those that are lymphocyte deficient. 8-10 week old animals (age and sex matched) were injected with Evan's blue post anesthetization. After waiting an hour the animals were euthanized and their brains were extracted and placed in RNALater for 24 hours. The brains were then sliced sagitally