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Liang, Z.

Publications and source records attributed to Liang, Z..

At least 127 records · Page 7Linked to original sources

Cell-type specific optogenetic fMRI on basal forebrain reveals functional network basis of behavioral preference

The basal forebrain (BF) is a complex structure that plays key roles in regulating various brain functions. However, it remains unclear how cholinergic and non-cholinergic BF neurons modulate large-scale functional networks and their relevance in intrinsic and extrinsic behaviors. With optimized awake mouse optogenetic fMRI approach, we revealed optogenetic stimulations of four BF neuron types evoked distinct cell-type specific whole-brain BOLD activations, which could attribute to BF-originated low dimensional structural networks. Additionally, optogenetic activation of VGLUT2, ChAT and PV neurons in BF modulated the preference of locomotion, exploration and grooming, respectively. Furthermore, we uncovered the functional network basis of the above BF-modulated behavioral preference, through a decoding model linking the BF-modulated BOLD activations, low dimensional structural networks, and behavioral preference. To summarize, we decoded functional network basis of differential behavioral preference with cell-type specific optogenetic fMRI on BF, and provided an avenue for investigating mouse behaviors from a whole-brain view.

neuroscience↗

Polymodal sensory perception of mechanical and chemical cues drives robust settlement and metamorphosis of a marine pre-vertebrate zooplanktonic larva.

The Earths oceans brim with an incredible diversity of microscopic planktonic animals, many of which correspond to the transient larval stage in the life cycles of benthic marine organisms. The mechanisms by which marine larvae use their nervous system to sense and process diverse environmental cues (physical and chemical) in the water column and the benthos to settle and metamorphose is a major problem across the fields of neuroscience, development, evolution and ecology, yet they remain largely unclear. Here, we employ Ca2+ imaging and behavioral assays using the larval form of the protochordate Ciona intestinalis to characterise the mechanical and chemical stimuli these larvae respond to during settlement and metamorphosis. We also identify the polymodal sensory cells that detect these stimuli. Whole brain Ca2+ imaging further revealed that the presentation or removal of ethological chemosensory stimuli engages the activities of different neuronal sub-populations resulting in brain state changes, which may underlie behavioral action selections and metamorphosis. Finally, chemogenetic interrogation coupled to behavioral analysis reveals that peptidergic sensory neurons including polymodal cells capable of chemotactile perception and chemosensory/neurosecretory cells of proto-placodal ectoderm origin play a pivotal role in regulating stimulus induced settlement and metamorphosis. This work suggests that marine zooplanktonic larvae utilise their streamlined nervous systems to perform multimodal integration of ethologically physical and chemical cues to explore the oceanic water column and benthos.

neuroscience↗

SWI/SNF chromatin remodeling determines brassinosteroid-induced transcriptional activation

The brassinosteroid (BR) hormone is a central modulator of plant growth, development, and responses to stresses by activating or repressing the expression of thousands of genes through the transcription factor BRASSINAZOLE-RESISTANT 1 (BZR1) and its homologues. However, the molecular mechanism that determines the transcriptional activation versus repression activity of BZR1 remains largely unclear. Here, we show that BZR1-responsive transcriptional activation at thousands of loci requires the Switch defective/sucrose non-fermentable (SWI/SNF)-complexes-mediated chromatin accessibility regulation. BR-activated BZR1 controls the activation or repression of thousands of BZR1 target genes through reprograming genome-wide chromatin accessibility landscape in Arabidopsis thaliana. BZR1 physically interacts with the BRAHMA (BRM)-Associated SWI/SNF complexes (BAS), co-localizes with BRM on the genome, and enhances BRM occupancy at sites of increased accessibility by BR. Loss of BRM abrogates the capacity of BZR1 to increase but not decrease chromatin accessibility, blocks BR-induced hypocotyl elongation, and diminishes BZR1-mediated transcriptional activation rather than repression. Together, our work reveals that the BAS chromatin remodeling complex is a critical epigenetic regulatory partner in dictating BZR1-mediated transcriptional activation ability, thus providing a long sought mechanistic explanation for how BR signaling activates gene transcription in shaping diverse developmental programs. TeaserBZR1-responsive transcriptional activation activity at thousands of loci requires the SWI/SNF-complexes-mediated chromatin accessibility regulation.

plant biology↗

Decoded EEG Neurofeedback-Guided Cognitive Reappraisal Training for Emotion Regulation

Neurofeedback is an innovative self-training that adjusts and enhances brain function. One of the more studied application scenarios with neurofeedback training is emotion regulation. Compared with regional brain activity-informed neurofeedback techniques, neurofeedback protocols using the decoded brain states as feedback signals could make the setting of regulation targets more specific and objective. In the present study, we constructed an EEG neurofeedback-guided cognitive reappraisal training protocol for emotion regulation. Forty-two healthy participants (20 females; 22.4{+/-}2.2 years old) were recruited and were randomly assigned to either the neurofeedback group or the control group. During the training process, we calculate the real-time self-regulation performance on the evoked emotion based on the decoded emotional states and fed it back to the subjects as the feedback signal. According to our results, real-time feedback of the regulation effect helps subjects improve emotion regulation performance for emotional stimuli with low positive valence. Further analysis of selected EEG features for emotion classification revealed the neural correlates with neurofeedback training. This newly proposed neurofeedback training protocol is a promising treatment for emotion-related mental disorders, with the potential to be a low-cost and high-portability brain-based, non-invasive, neural modulation technique.

neuroscience↗

PCBP1 regulates alternative splicing of AARS2 in congenital cardiomyopathy

Alanyl-transfer RNA synthetase 2 (AARS2) is a nuclear encoded mitochondrial tRNA synthetase that is responsible for charging of tRNA-Ala with alanine during mitochondrial translation. Homozygous or compound heterozygous mutations in the Aars2 gene, including those affecting its splicing, are linked to infantile cardiomyopathy in humans. However, how Aars2 regulates heart development, and the underlying molecular mechanism of heart disease remains unknown. Here, we found that poly(rC) binding protein 1 (PCBP1) interacts with the Aars2 transcript to mediate its alternative splicing and is critical for the expression and function of Aars2. Cardiomyocyte-specific deletion of Pcbp1 in mice resulted in defects in heart development that are reminiscent of human congenital cardiac defects, including noncompaction cardiomyopathy and a disruption of the cardiomyocyte maturation trajectory. Loss of Pcbp1 led to an aberrant alternative splicing and a premature termination of Aars2 in cardiomyocytes. Additionally, Aars2 mutant mice with exon-16 skipping recapitulated heart developmental defects observed in Pcbp1 mutant mice. Mechanistically, we found dysregulated gene and protein expression of the oxidative phosphorylation pathway in both Pcbp1 and Aars2 mutant hearts; these date provide further evidence that the infantile hypertrophic cardiomyopathy associated with the disorder oxidative phosphorylation defect type 8 (COXPD8) is mediated by Aars2. Our study therefore identifies Pcbp1 and Aars2 as critical regulators of heart development and provides important molecular insights into the role of disruptions in metabolism on congenital heart defects.

developmental biology↗

Social navigation: distance and grid-like codes support navigation of abstract social space in the human brain

People form impressions about others during daily social encounters and infer personality traits from others behaviors. Such trait inference is thought to rely on two universal dimensions, i.e., competence and warmth. These two dimensions can be used to construct a social cognitive map organizing massive information obtained from social encounters efficiently. Originated from spatial cognition, the neural codes supporting representation and navigation of spatial cognitive map has been widely studied. Recent studies suggest similar neural mechanism subserves the map-like architecture in social cognition as well. Here we investigated how spatial codes operate beyond physical environment and support the representation and navigation of social cognitive map. We designed a social value space defined by two dimensions of competence and warmth. Behaviorally, participants were able to navigate to a learned location from random starting locations in this abstract social space. At neural level, we identified representation of distance in precuneus, fusiform gyrus and middle occipital gyrus. We also found partial evidence of grid-like representation patterns in medial prefrontal cortex and entorhinal cortex. Moreover, the intensity of grid-like response scaled with performance of navigating in social space and social avoidance trait scores. Our findings suggest a neurocognitive mechanism by which social information can be organized into a structured representation namely cognitive map and its relevance to social well-being.

neuroscience↗

Contribution of the IGCR1 regulatory element and the 3'Igh CBEs to Regulation of Igh V(D)J Recombination

Immunoglobulin heavy chain variable region exons are assembled in progenitor-B cells, from VH, D, and JH gene segments located in separate clusters across the Igh locus. RAG endonuclease initiates V(D)J recombination from a JH-based recombination center (RC). Cohesin-mediated extrusion of upstream chromatin past RC-bound RAG presents Ds for joining to JHs to form a DJH-RC. Igh has a provocative number and organization of CTCF-binding-elements (CBEs) that can impede loop extrusion. Thus, Igh has two divergently oriented CBEs (CBE1 and CBE2) in the IGCR1 element between the VH and D/JH domains, over 100 CBEs across the VH domain convergent to CBE1, and 10 clustered 3Igh-CBEs convergent to CBE2 and VH CBEs. IGCR1 CBEs segregate D/JH and VH domains by impeding loop extrusion-mediated RAG-scanning. Down-regulation of WAPL, a cohesin unloader, in progenitor-B cells neutralizes CBEs, allowing DJH-RC-bound RAG to scan the VH domain and perform VH-to-DJH rearrangements. To elucidate potential roles of IGCR1-based CBEs and 3Igh-CBEs in regulating RAG-scanning and elucidate the mechanism of the "ordered" transition from D-to-JH to VH-to-DJH recombination, we tested effects of deleting or inverting IGCR1 or 3Igh-CBEs in mice and/or progenitor-B cell lines. These studies revealed that normal IGCR1 CBE orientation augments RAG-scanning impediment activity and suggest that 3Igh-CBEs reinforce ability of the RC to function as a dynamic loop extrusion impediment to promote optimal RAG scanning activity. Finally, our findings indicate that ordered V(D)J recombination can be explained by a gradual WAPL down-regulation mechanism in progenitor B cells as opposed to a strict developmental switch. SIGNIFICANCE STATEMENTTo counteract diverse pathogens, vertebrates evolved adaptive immunity to generate diverse antibody repertoires through a B lymphocyte-specific somatic gene rearrangement process termed V(D)J recombination. Tight regulation of the V(D)J recombination process is vital to generating antibody diversity and preventing off-target activities that can predispose the oncogenic translocations. Recent studies have demonstrated V(D)J rearrangement is driven by cohesin-mediated chromatin loop extrusion, a process that establishes genomic loop domains by extruding chromatin, predominantly, between convergently-oriented CTCF looping factor-binding elements (CBEs). By deleting and inverting CBEs within a critical antibody heavy chain gene locus developmental control region and a loop extrusion chromatin-anchor at the downstream end of this locus, we reveal how these elements developmentally contribute to generation of diverse antibody repertoires.

immunology↗

A hierarchical strategy to decipher protein dynamics in vivo with chemical cross-linking mass spectrometry

Protein dynamics are essential for their various functions. Meanwhile, the intracellular environment would affect protein structural dynamics, especially for the intrinsically disordered proteins (IDPs). Chemical cross-linking mass spectrometry (CXMS) can unbiasedly capture the protein conformation information in cells and can also represent the protein dynamics. Here, we proposed a hierarchy deciphering strategy for protein dynamics in vivo. With the prior structure from AlphaFold2, the steady local conformation can be extensively evaluated. On this basis, the full-length structure of multi-domain proteins with various dynamic features can be characterized using CXMS. Furthermore, the complementary strategy with unbiased sampling and distance-constrained sampling enables an objective description of the intrinsic motion of the IDPs. Therefore, the hierarchy strategy we presented herein could help us better understand the molecular mechanisms of protein functions in cells.

cell biology↗

Membrane and glycocalyx tethering of DNA nanostructures for enhanced uptake

DNA nanostructures (DNs) have been increasingly utilized in biosensing, drug delivery, diagnostics and therapeutics, because of their programmable assembly, control over size and shape, and ease of functionalization. However, the low cellular uptake of DNs has limited their effectiveness in these biomedical applications. Here we demonstrate the potential of membrane and glycocalyx binding as general strategies to enhance the cellular uptake of DNs. By targeting the plasma membrane and cell-surface glycocalyx, the uptake of all three distinct DNs is significantly enhanced as compared to uptake of bare DNs. We also demonstrate the viability of single-step membrane labeling by cholesterol-DNs as competitive with previous multistep approaches. Further, we show that the endocytic pathway of membrane-bound DNs is an interdependent process that involves scavenger receptors, clathrin-, and caveolinmediated endocytosis. Our findings may potentially expand the toolbox for effective cellular delivery of DNA nanostructured systems.

bioengineering↗

Resting-state functional brain network alternations related to non-suicidal and suicidal self-injurious behaviors in adolescents with depression

Nonsuicidal self-injury (NSSI) and suicidal attempt (SA) frequently occur during depressed adolescents, but the underlying neurobiological mechanisms are poorly understood. The maturation of network connectivity is a central feature of brain development during adolescence. However, few researchers have used resting-state functional magnetic resonance imaging (fMRI) to investigate the similarities and differences in the intrinsic brain networks between NSSI with NSSI+SA in depressed adolescent populations. In this study, we collected self-reported questionnaires and resting-state (fMRI data from a sample of depressed adolescents (N = 114), categorized into three groups: clinical control (non-self-harm), NSSI-only, and NSSI+SA based on their self-harm history. The alternations of FC patterns were identified through support vector machine-based classification, as machine learning approaches can help to overcome the multiple-comparison problems of their multivariate nature. Referring to the convergent alternations between adolescent NSSI with or without a history of SA, the alternations of intra-/inter-network FCs among the Control, SalVAtten, Limbic, and Default networks. Besides, divergent alternations were also observed for depressed adolescents with a history of SA, involving the Limbic, DorsAttn, Visual, and Subcortical networks. Besides, the severity of depressive symptoms only showed a significant correlation with altered FCs in Limbic-DorAttn and Limbic-Visual networks, strengthening the fact that these observed alternations of FC could not all be explained by increased depression severity. The emphasis of this study on the network basis could extend the existing evidence at a circuit level and the observed convergent alternations may explain an underlying neurobiological mechanism pertaining to the continuum of self-destructiveness in adolescents. In addition, our discovery of divergent alternations could help to identify biomarkers that will aid in differentiating those at risk for SA among those engaging in NSSI and contribute to the development of neurobiologically informed interventions.

neuroscience↗

CRB3 navigates Rab11 trafficking vesicles to promote γTuRC assembly during ciliogenesis

The primary cilium plays important roles in regulating cell differentiation, signal transduction, and tissue organization. Dysfunction of the primary cilium can lead to ciliopathies and cancer. The formation and organization of the primary cilium are highly associated with cell polarity proteins, such as the apical polarity protein CRB3. However, the molecular mechanisms by which CRB3 regulates ciliogenesis and the location of CRB3 remain unknown. Here, we show that CRB3, as a navigator, regulates vesicle trafficking in {gamma}-TuRC assembly during ciliogenesis and cilium-related Hh and Wnt signaling pathways in tumorigenesis. Crb3 knockout mice display severe defects of the primary cilium in the mammary ductal lumen and renal tubule, while mammary epithelial-specific Crb3 knockout mice exhibit the promotion of ductal epithelial hyperplasia and tumorigenesis. CRB3 is essential for lumen formation and ciliary assembly in the mammary epithelium. We demonstrate that CRB3 localizes to the basal body and that CRB3 trafficking is mediated by Rab11-positive endosomes. Significantly, CRB3 interacts with Rab11 to navigate GCP6/Rab11 trafficking vesicles to CEP290, resulting in intact {gamma}-TuRC assembly. In addition, CRB3-depleted cells are unresponsive to the activation of the Hh signaling pathway, while CRB3 regulates the Wnt signaling pathway. Therefore, our studies reveal the molecular mechanisms by which CRB3 recognizes Rab11-positive endosomes to facilitate ciliogenesis, and regulates cilium-related signaling pathways in tumorigenesis.

cell biology↗

ADAR1p150 Prevents MDA5 and PKR Activation via Distinct Mechanisms to Avert Fatal Autoinflammation

Effective immunity requires the innate immune system to distinguish foreign (non-self) nucleic acids from cellular (self) nucleic acids. Cellular double-stranded RNAs (dsRNAs) are edited by the RNA editing enzyme ADAR1 to prevent their dsRNA structure pattern being recognized as viral dsRNA by cytoplasmic dsRNA sensors including MDA5, PKR and ZBP1. A loss of ADAR1-mediated RNA editing of cellular dsRNA activates MDA5. However, additional RNA editing-independent functions of ADAR1 have been proposed, but a specific mechanism has not been delineated. We now demonstrate that the loss of ADAR1-mediated RNA editing specifically activates MDA5, while loss of the cytoplasmic ADAR1p150 isoform or its dsRNA binding activity enabled PKR activation. Deleting both MDA5 and PKR resulted in complete rescue of the embryonic lethality of Adar1p150-/- mice to adulthood, contrasting with the limited or no rescue by removing MDA5, PKR or ZBP1 alone, demonstrating that this is a species conserved function of ADAR1p150. Our findings demonstrate that MDA5 and PKR are the primary in vivo effectors of fatal autoinflammation following the loss of ADAR1p150.

genetics↗

Anoctamin 10/TMEM16K mediates convergent extension and tubulogenesis during notochord formation in the early chordate Ciona intestinalis.

During embryonic development, cells are organized into complex tissues and organs. A highly conserved organ shape across metazoans is the epithelial tube. Tube morphogenesis is a complex multistep process where the molecular mechanisms underlying the diversity of cell behaviors such as convergent extension, cell elongation, and lumen formation are still intensely studied. Here, using genome editing and quantitative imaging in the early chordate Ciona intestinalis we show that Ano10/Tmem16k, a member of the evolutionarily ancient family of transmembrane proteins called Anoctamin/TMEM16 is required for convergent extension, lumen expansion and connection during notochord morphogenesis. In addition, we find that loss of Cii.Ano10/Tmem16k hampers cell behavior and cytoskeletal organization during tubulogenesis. In vivo Ca2+ imaging revealed that genetic ablation of Cii.Ano10/Tmem16k hinders the ability of notochord cells to regulate bioelectrical signaling. Finally, we use electrophysiological recordings and a scramblase assay in tissue culture to demonstrate that Cii.Ano10/Tmem16k likely acts as an ion channel but not as a phospholipid scramblase. More generally, this work provides insights into the pre-vertebrate functions of Anoctamins and raises the possibility that Anoctamin/Tmem16 family members have an evolutionarily conserved role in tube morphogenesis.

developmental biology↗

Towards reliable reconstruction of the mouse brain thalamocortical connectivity using diffusion MRI

Diffusion magnetic resonance imaging (dMRI) tractography has yielded intriguing insights into brain circuits and their relationship to behavior in response to gene mutations or neurological diseases across a number of species. Still, existing tractography approaches suffer from limited sensitivity and specificity, leading to uncertain interpretation of the reconstructed connections. Hence, in this study, we aimed to optimize the imaging and computational pipeline for reliable reconstruction of the mouse brain thalamocortical network. We developed a dMRI-based atlas of the mouse forebrain with structural labels imported from the Allen Mouse Brain Atlas (AMBA). Using the atlas and tracer data from the Allen Mouse Brain Connectivity Atlas (AMBCA) as ground truth, we investigated the accuracy of reconstructed node-to-node thalamocortical structural connectivity and effects of imaging and tractography parameters. Our results suggest that these parameters significantly affect tractography outcomes and our atlas can be used to investigate macroscopic structural connectivity in the mouse brain. Furthermore, tractography in mouse brain gray matter still face challenges and need improved imaging and tractography methods.

bioengineering↗

Zn2+ potentiation of OTOP proton channels identifies structural elements of the gating apparatus

Otopetrin proteins (OTOPs) form proton-selective ion channels that are expressed in diverse cell types where they may mediate detection of acids or regulation of pH. In vertebrates there are three family members: OTOP1 is required for formation of otoconia in the vesibular system and it forms the receptor for sour taste, while the functions of OTOP2, and OTOP3 are not yet known. Importantly, the gating mechanisms of any of the OTOP channels are not well-understood, and until recently, it was not even known if the channels were gated. Here we show that Zn2+, as well as other transition metals including copper (Cu2+), potently activate murine OTOP3. Zn2+ pre-exposure increases the magnitude of OTOP3 currents to a subsequent acid stimulus by as much as 10-fold. In contrast, OTOP2 currents are insensitive to potentiation by Zn2+. Swapping the extracellular tm 11-12 linker between OTOP3 and OTOP2 was sufficient to eliminate Zn2+ potentiation of OTOP3 and confer Zn2+ potentiation on OTOP2. We also show that H531 within the tm 11-12 linker is essential for potentiation of OTOP3 by Zn2+, likely by forming part of its binding site. Kinetic modeling of the data is consistent with Zn2+ stabilizing the open state of the channel, possibly competing with H+ for activation of the channels. These results establish the tm 11-12 linker as part of the gating apparatus of OTOP channels and a target for drug discovery. Zinc is an essential micronutrient and its regulation of OTOP channels will undoubtedly have important physiological sequelae. Significance StatementA family of proton-activated H+ ion channels was recently identified that includes the sour receptor OTOP1. Here we show that members of the OTOP channel family are differentially sensitive to Zn2+, which strongly activates OTOP3 but not OTOP2. By studying chimeric channels, we identify structural elements in the extracellular linker between transmembrane domains 11-12 that are necessary and sufficient for Zn2+ activation of OTOP channels. In addition to the taste system, OTOP channels play important roles in biomineralization in both vertebrate and invertebrates and are expressed in the digestive tract where their expression is a predictor of cancer prognosis. Our identification of the tm 11-12 linker as part of the gating apparatus makes it a promising target for pharmaceutical discovery.

biophysics↗

A Brain-Wide Genome-Wide Association Study of Candidate Quantitative Trait Loci Associated with Structural and Functional Phenotypes of Pain Sensitivity

Individual pain sensitivity is influenced by many factors, such as the differentiation of brain regional features and genetic variations. However, its heritability remains largely unclear. The present study conducted a brain-wide genome-wide association study (GWAS) to explore the genetic bases of structural and functional neuroimage phenotypes of pain sensitivity. In total 432 normal participants were firstly divided into high and low pain sensitivity groups according to laser quantitative test threshold and related brain regions gray matter density (GMD) features were identified. Consequently, GWAS was performed on each GMD phenotype using quality-controlled genotypes. Based on the heatmap and hierarchical clustering results from GWAS, the right insula was selected for further refined analysis in terms of sub-regions GMD and resting-state functional connectivity (rs-FC) phenotypes. The results indicate that the right insula GMD in the high sensitivity group is significantly lower than the low sensitivity group. Also, the TT/TC group at locus rs187974 may lead to a lower GMD in the right insula than the CC group. Meanwhile, loci at gene CYP2D6 may lead to a variation of rs-FC between the right insula and left putamen. In conclusion, our study suggests multiple candidate loci associated with pain sensitivity that may influence brain phenotypes.

genomics↗

Organization, genomic targeting and assembly of three distinct SWI/SNF chromatin remodeling complexes in Arabidopsis

Switch defective/sucrose non-fermentable (SWI/SNF) complexes are evolutionarily conserved multi-subunit machines that play vital roles in chromatin architecture regulation for modulating gene expression via sliding or ejection of nucleosomes in eukaryotes. In plants, perturbations of SWI/SNF subunits often result in severe developmental disorders. However, the subunit composition, pathways of assembly, and genomic targeting of the plant SWI/SNF complexes remain undefined. Here, we reveal the organization, genomic targeting and assembly of three distinct Arabidopsis SWI/SNF complexes: BRAHMA-Associated SWI/SNF complexes (BAS), SPLAYED-Associated SWI/SNF complexes (SAS) and MINUSCULE-Associated SWI/SNF complexes (MAS). We show that BAS complexes are equivalent to human ncBAF, whereas SAS and MAS complexes evolve in multiple subunits unique to plants, suggesting a plant-specific functional evolution of SWI/SNF complexes. We further demonstrate overlapping and specific genomic targeting of the three plant SWI/SNF complexes on chromatin and reveal that SAS complexes are necessary for the correct genomic localization of the BAS complexes. Finally, we define the role of core module subunit in the assembly of the plant SWI/SNF complexes and highlight that ATPase module subunit is required for global complex stability and the interaction of core module subunits in SAS and BAS complexes in Arabidopsis. Together, our work highlights the divergence of SWI/SNF chromatin remodelers during the eukaryote evolution and provides a comprehensive landscape for understanding the plant SWI/SNF complexes organization, assembly, genomic targeting, and function. One-sentence summaryComprehensively define the organization, genomic targeting and assembly of three distinct SWI/SNF chromatin remodeling complexes in Arabidopsis

plant biology↗

Instantaneous antidepressant effect of lateral habenula deep brain stimulation in rats studied with functional magnetic resonance imaging

The available treatments for depression have substantial limitations, including low response rates and substantial lag time before a response is achieved. We applied deep brain stimulation (DBS) to the lateral habenula (LHb) of two rat models of depression (Wistar Kyoto rats and lipopolysaccharide-treated rats) and observed an immediate (within seconds to minutes) alleviation of depressive-like symptoms with a high response rate. Simultaneous functional magnetic resonance imaging (fMRI) conducted on the same sets of depressive rats used in behavioral tests revealed DBS-induced activation of multiple regions in afferent and efferent circuitry of the LHb. The activation levels of brain regions connected to the medial LHb (M-LHb) was correlated with the extent of behavioral improvements. Rats with more medial stimulation sites in the LHb exhibited greater antidepressant effects than those with more lateral stimulation sites. These results indicated that the antidromic activation of the limbic system and orthodromic activation of the monoaminergic systems connected to the M-LHb played a critical role in the rapid antidepressant effects of LHb-DBS. This study indicates that M-LHb-DBS might act as a valuable, rapid-acting antidepressant therapeutic strategy for treatment-resistant depression and demonstrates the potential of using fMRI activation of specific brain regions as biomarkers to predict and evaluate antidepressant efficacy.

neuroscience↗