Altered static and dynamic functional connectivity of habenula in first-episode, drug-naïve schizophrenia patients, and their association with symptoms including hallucination and anxiety

Surrogate GPR139 Agonists Reverse Short-Term Startle Habituation Impairment in Larval Zebrafish

GPR139, an orphan G-protein coupled receptor predominantly expressed in the habenula, has recently been implicated in understanding neurobehavior and neuropsychiatric disorders. Surrogate agonists for human GPR139 have shown the potential to alleviate cognitive impairment associated with schizophrenia in rodent models and human clinical trials. Yet, the effect of GPR139 agonists on the neurophysiological properties of the habenula remains elusive. We examined the effect of GPR139 agonists (JNJ-63533054 and TAK-041) on short-term startle habituation of 6-day post-fertilization (dpf) larval zebrafish (Danio rerio) in an automated solenoid setup and on reversing the pharmacologically impaired startle habituation. GPR139 agonists enhanced startle habituation at the lowest tested concentrations, whereas moderate and highest concentrations delayed startle habituation. Furthermore, GPR139 agonists reversed the non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist MK-801-induced startle habituation impairment. Using exponential decay curve fit analysis, we found that the lowest concentration of GPR139 agonists performed better than moderate and highest concentrations in reversing the MK-801-induced impairment of startle habituation. Using in vivo GCaMP calcium imaging and phosphorylated extracellular-signal-regulated kinase (pERK) as a proxy for neural activity, we found that GPR139 agonists exerted effects on the habenula activities at the habituated state but not during the spontaneous state (without startle habituation paradigm), suggesting the GPR139 agonists-evoked neural activation in the habenula is sensory stimuli-dependent. Moreover, both GPR139 agonists differently reduced MK-801-induced hyperexcitability of the habenula at both spontaneous and habituated states. Taken together, we showed that GPR139 agonists reverse startle habituation impairment caused by MK-801 via the normalization of hyperexcitability of zebrafish habenula.

Voxel-based alterations in spontaneous brain activity among very-late-onset schizophrenia-like psychosis: A preliminary resting-state functional magnetic resonance imaging study

BACKGROUND

Very late-onset schizophrenia-like psychosis (VLOSLP) is a subtype of schizophrenia spectrum disorders in which individuals experience psychotic symptoms for the first time after the age of 60. The incidence of VLOSLP shows a linear relationship with increasing age. However, no studies have reported alterations in spontaneous brain activity among VLOSLP patients and their correlation with cognitive function and clinical symptoms.

AIM

To explore VLOSLP brain activity and correlations with cognitive function and clinical symptoms using resting-state functional magnetic resonance imaging.

METHODS

This study included 33 VLOSLP patients and 34 healthy controls. The cognitive assessment utilized the Mini Mental State Examination, Montreal Cognitive Assessment, and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Clinical characteristic acquisition was performed via the Positive and Negative Syndrome Scale (PANSS). All participants were scanned via resting-state functional magnetic resonance imaging, and the data were processed using amplitude of low-frequency fluctuations (ALFF), fractional ALFF (fALFF), regional homogeneity, and voxel-mirrored homotopic connectivity (VMHC).

RESULTS

The VLOSLP group presented decreased ALFF values in the left cuneus, right precuneus, right precentral gyrus, and left paracentral lobule; increased fALFF values in the left caudate nucleus; decreased fALFF values in the right calcarine fissure and surrounding cortex (CAL) and right precuneus; increased regional homogeneity values in the right putamen; and decreased VMHC values in the bilateral CAL, bilateral superior temporal gyrus, and bilateral cuneus. In the VLOSLP group, ALFF values in the right precuneus were negatively correlated with Mini Mental State Examination score and PANSS positive subscale score, and VMHC values in the bilateral CAL were negatively correlated with the RBANS total score, RBANS delayed memory score, and PANSS positive subscale score.

CONCLUSION

The changes of brain activity in VLOSLP are concentrated in the right precuneus and bilateral CAL regions, which may be associated with cognitive impairment and clinically positive symptoms.

Predictive neural processing of self-generated hand and tool actions in patients with schizophrenia spectrum disorders and healthy individuals

Schizophrenia spectrum disorders (SSD) have been linked to dysfunctions in the predictive neural suppression of sensory input elicited by one's own actions. Such motor predictions become particularly challenging during tool use and when feedback from multiple sensory modalities is present. In this study, we investigated the neural correlates and potential dysfunctions of action feedback processing in SSD during tool use actions and bimodal sensory feedback presentation. Patients with SSD (NTotal = 42; schizophrenia NF20 = 34; schizoaffective disorder NF25 = 6; other N = 2) and healthy controls (HC, N = 27) performed active or passive hand movements with or without a tool and received unimodal (visual; a video of their hand movement) or bimodal (visual and auditory) feedback with various delays (0, 83, 167, 250, 333, 417 ms). Subjects reported whether they detected a delay. A subgroup (NSSD = 20; NHC = 20) participated in an identical fMRI experiment. Both groups reported fewer delays in active than passive conditions and exhibited neural suppression in all conditions in occipital and temporoparietal regions, cerebellum, and SMA. Group differences emerged in right cuneus, calcarine, and middle occipital gyrus, with reduced active-passive differences in patients during tool use actions and in bimodal trials during actions performed without a tool. These results demonstrate for the first time that, although patients and HC show similarities in neural suppression, higher-level visual processing areas fail to adequately distinguish between self- and externally generated sensory input in patients, particularly in complex action feedback scenarios involving bimodal action feedback and feedback elicited by tool use actions.

Advances in MRI Research for First-Episode Schizophrenia: A Selective Review and NSFC-Funded Analysis

BACKGROUND AND HYPOTHESES

The causes of schizophrenia remain unclear, and research has been hindered by the lack of quantifiable standards. However, magnetic resonance imaging (MRI) is addressing these challenges, revealing critical neurobiological details and emphasizing its importance in both evaluation and treatment.

STUDY DESIGN

First, we reviewed the progress of research on structural MRI (sMRI), functional MRI (fMRI), multimodal/multiomics analysis, artificial intelligence, and neuromodulation in first-episode schizophrenia (FES) over the past 5 years. Second, we summarize the current state of schizophrenia research funded by the National Natural Science Foundation of China (NSFC) to facilitate academic exchange and cooperation both domestically and internationally.

STUDY RESULTS

sMRI has identified early neurodevelopmental biomarkers in FES patients, and fMRI has highlighted functional abnormalities across disease stages. Multimodal/multiomics analysis has revealed complex brain-neurobiology interactions. Neuromodulation techniques, which directly modulate neural activity in specific brain regions, offer promising long-term benefits for stabilizing conditions and enhancing patients' quality of life. NSFC-funded analysis shows China is increasing its funding for schizophrenia research, though funding distribution remains uneven. The research focus has shifted from a single perspective on brain structure and function to multichannel, multimodal comprehensive analysis methods. This progress has driven the integration of machine learning-driven multiomics research, aiming to construct disease classification models, explore disease mechanisms, and guide treatment from multidimensional and interdisciplinary perspectives.

CONCLUSIONS

MRI technology has provided new perspectives for the diagnosis and treatment of schizophrenia, especially the neurobiological foundations of the disease. Support from the NSFC provides a scientific and financial basis for future research and treatment, heralding scientific discoveries and technological innovations in this field and bringing hope to schizophrenia patients.

Alterations of interhemispheric functional connectivity in patients with hypertensive retinopathy using voxel-mirrored homotopic connectivity: a resting state fMRI study

AIM

To analyze whether alterations of voxel mirror homology connectivity (VMHC) values, as determined by resting-state functional magnetic resonance imaging (rs-fMRI), occur in cerebral regions of patients with hypertensive retinopathy (HR) and to determine the relationship between VMHC values and clinical characteristics in patients with HR.

METHODS

Twenty-one patients with HR and 21 age-matched healthy controls (HCs) were assessed by rs-fMRI scanning. The functional connectivity between the hemispheres of the cerebrum was assessed by measuring VMHC, with the ability of VMHC to distinguish between the HR and HC groups assessed using receiver operating characteristic (ROC) curve analysis. Differences in the demographic and clinical characteristics of the HR and HC groups were analyzed by independent sample t-tests. The relationship between average VMHC in several brain areas of HR patients and clinical features was determined using Pearson correlation analysis.

RESULTS

Mean VMHC values of the bilateral cuneus gyrus (BA19), bilateral middle orbitofrontal gyrus (BA47), bilateral middle temporal gyrus (BA39) and bilateral superior medial frontal gyrus (BA9) were lower in the HR than in the HC group.

CONCLUSION

VMHC values can predict the development of early HR, prevent the transformation of hypertensive microangiopathy, and provide useful information explaining the changes in neural mechanism associated with HR.

Peripheral blood complement factors C2 and C3 as biomarkers of clinical efficacy in patients with first-episode schizophrenia after aripiprazole treatment

OBJECTIVE

The objective of this study was to identify serum complement factor-based biomarkers indicative of clinical efficacy in patients with first-episode schizophrenia (SCZ) following treatment with aripiprazole.

METHODS

The retrospective study cohort comprised 40 patients diagnosed with first-episode SCZ (SCZ group) and 40 healthy individuals (control group). Quantitative analyses were conducted on five complement factors, namely complement component 1 (C1), C2, C3, C4, and the 50% hemolytic complement (CH50). Baseline serum complement factor levels were compared between the SCZ and control groups. Patients diagnosed with SCZ underwent a 4-week treatment regimen with aripiprazole. The severity of psychiatric symptoms in these patients was assessed using the Positive and Negative Symptom Scale (PANSS) and the Brief Psychiatric Rating Scale-18 Item Version (BPRS). Comparative analyses were conducted on PANSS and BPRS scores, as well as serum complement factor levels, both prior to (pre-treatment group) and following aripiprazole administration (post-treatment group). Pearson's correlation test was employed to evaluate the relationships between changes in serum complement factor levels and the reduction rates of PANSS/BPRS scores.

RESULTS

At baseline, patients with SCZ exhibited significantly elevated levels of C1, C2, C3, C4, and CH50 compared to the control group (P < 0.05). Moreover, following treatment, there was a significant reduction in the PANSS total score, positive symptom score, negative symptom score, and BPRS score in the post-treatment group compared to the pre-treatment group (P < 0.05). Furthermore, patients in the post-treatment group exhibited a significant reduction in serum levels of C2, C3, and C4, alongside a significant increase in the serum level of CH50 compared to those in the pre-treatment group (P < 0.05). Additionally, the baseline serum C2 levels and the variations in serum C2 levels pre- and post-treatment exhibited a negative correlation with the reduction rate of PANSS/BPRS scores (P < 0.05). Similarly, both the baseline serum C3 levels and the changes in serum C3 levels pre- and post-treatment were negatively correlated with the reduction rate of PANSS/BPRS scores (P < 0.05).

CONCLUSION

Baseline serum levels of C2 and C3, as well as their variations pre- and post-treatment, may serve as biomarkers for predicting clinical efficacy in patients with first-episode SCZ undergoing treatment with aripiprazole.

Distinct Chrna5 mutations link excessive alcohol use to types I/II vulnerability profiles and IPN GABAergic neurons

Genome wide association and animal studies have implicated genetic variations in CHRNΑ5, encoding the α5 subunit-containing nicotinic acetylcholine receptors (α5*nAChRs), as a risk factor for developing alcohol use disorders (AUDs). To understand how α5*nAChR mutations may influence alcohol (EtOH) drinking behavior, we used a two-bottle choice procedure with intermittent access to alcohol in male and female transgenic mice expressing either the highly frequent human single nucleotide polymorphism (α5SNP/rs16969968) or a deletion of the Chrna5 gene (α5KO). AUDs-related preconsommatory traits (anxiety, sensation-seeking and impulsivity) were assessed with a battery of relevant tasks (elevated-plus maze, novel place preference and step-down inhibitory avoidance). The implication of the α5-expressing IPN GABAergic neurons in AUDs and related behavioral traits was verified using neurospecific lentiviral (LV)-induced reexpression of the α5 subunit in α5KOxGAD-Cre mice. Both α5SNP and α5KO mice showed over-consumption of EtOH, but displayed opposite vulnerability profiles consistent with Cloninger's subtypes of human AUDs. α5SNP mice showed Type I-like characteristics, i.e., high anxiety, novelty avoidance, whereas α5KOs exhibited Type II-like features such as low anxiety and high impulsivity. LV re-expression of the α5 subunit in IPN GABAergic neurons restored the control of EtOH intake and improved the impulsive phenotype. We demonstrate that the SNP (rs16969968) or null mutation of Chrna5 result in increased volitional EtOH consumption but opposite effects on anxiety, novelty-seeking and impulsive-like behaviors that match Cloninger type I and II of AUDs, including sex-related variations. IPN GABAergic neurons expressing α5*nAChRs play a key role in limiting both EtOH drinking and motor impulsivity.

A functional schizophrenia-associated genetic variant near the TSNARE1 and ADGRB1 genes

Recent collaborative genome-wide association studies (GWAS) have identified >200 independent loci contributing to risk for schizophrenia (SCZ). The genes closest to these loci have diverse functions, supporting the potential involvement of multiple relevant biological processes, yet there is no direct evidence that individual variants are functional or directly linked to specific genes. Nevertheless, overlap with certain epigenetic marks suggest that most GWAS-implicated variants are regulatory. Based on the strength of association with SCZ and the presence of regulatory epigenetic marks, we chose one such variant near TSNARE1 and ADGRB1, rs4129585, to test for functional potential and assay differences that may drive the pathogenicity of the risk allele. We observed that the variant-containing sequence drives reporter expression in relevant neuronal populations in zebrafish. Next, we introduced each allele into human induced pluripotent cells and differentiated four isogenic clones homozygous for the risk allele and five clones homozygous for the non-risk allele into neural progenitor cells. Employing RNA sequencing, we found that the two alleles yield significant transcriptional differences in the expression of 109 genes at a false discovery rate (FDR) of <0.05 and 259 genes at a FDR of <0.1. We demonstrate that these genes are highly interconnected in pathways enriched for synaptic proteins, axon guidance, and regulation of synapse assembly. Exploration of genes near rs4129585 suggests that this variant does not regulate TSNARE1 transcripts, as previously thought, but may regulate the neighboring ADGRB1, a regulator of synaptogenesis. Our results suggest that rs4129585 is a functional common variant that functions in specific pathways likely involved in SCZ risk.

Transcriptomic analysis of the human habenula in schizophrenia

Pathophysiology of many neuropsychiatric disorders, including schizophrenia (SCZD), is linked to habenula (Hb) function. While pharmacotherapies and deep brain stimulation targeting the Hb are emerging as promising therapeutic treatments, little is known about the cell type-specific transcriptomic organization of the human Hb or how it is altered in SCZD. Here we define the molecular neuroanatomy of the human Hb and identify transcriptomic changes in individuals with SCZD compared to neurotypical controls. Utilizing Hb-enriched postmortem human brain tissue, we performed single nucleus RNA-sequencing (snRNA-seq; n=7 neurotypical donors) and identified 17 molecularly defined Hb cell types across 16,437 nuclei, including 3 medial and 7 lateral Hb populations, several of which were conserved between rodents and humans. Single molecule fluorescent in situ hybridization (smFISH; n=3 neurotypical donors) validated snRNA-seq Hb cell types and mapped their spatial locations. Bulk RNA-sequencing and cell type deconvolution in Hb-enriched tissue from 35 individuals with SCZD and 33 neurotypical controls yielded 45 SCZD-associated differentially expressed genes (DEGs, FDR < 0.05), with 32 (71%) unique to Hb-enriched tissue. eQTL analysis identified 717 independent SNP-gene pairs (FDR < 0.05), where either the SNP is a SCZD risk variant (16 pairs) or the gene is a SCZD DEG (7 pairs). eQTL and SCZD risk colocalization analysis identified 16 colocalized genes. These results identify topographically organized cell types with distinct molecular signatures in the human Hb and demonstrate unique genetic changes associated with SCZD, thereby providing novel molecular insights into the role of Hb in neuropsychiatric disorders.

One Sentence Summary

Transcriptomic analysis of the human habenula and identification of molecular changes associated with schizophrenia risk and illness state.

A Functional Schizophrenia-associated genetic variant near the TSNARE1 and ADGRB1 genes

Recent collaborative genome wide association studies (GWAS) have identified >200 independent loci contributing to risk for schizophrenia (SCZ). The genes closest to these loci have diverse functions, supporting the potential involvement of multiple relevant biological processes; yet there is no direct evidence that individual variants are functional or directly linked to specific genes. Nevertheless, overlap with certain epigenetic marks suggest that most GWAS-implicated variants are regulatory. Based on the strength of association with SCZ and the presence of regulatory epigenetic marks, we chose one such variant near TSNARE1 and ADGRB1, rs4129585, to test for functional potential and assay differences that may drive the pathogenicity of the risk allele. We observed that the variant-containing sequence drives reporter expression in relevant neuronal populations in zebrafish. Next, we introduced each allele into human induced pluripotent cells and differentiated 4 isogenic clones homozygous for the risk allele and 5 clones homozygous for the non-risk allele into neural precursor cells. Employing RNA-seq, we found that the two alleles yield significant transcriptional differences in the expression of 109 genes at FDR <0.05 and 259 genes at FDR <0.1. We demonstrate that these genes are highly interconnected in pathways enriched for synaptic proteins, axon guidance, and regulation of synapse assembly. Exploration of genes near rs4129585 suggests that this variant does not regulate TSNARE1 transcripts, as previously thought, but may regulate the neighboring ADGRB1, a regulator of synaptogenesis. Our results suggest that rs4129585 is a functional common variant that functions in specific pathways likely involved in SCZ risk.

Regional Dynamic Neuroimaging Changes of Adults with Autism Spectrum Disorder

Most neuroimaging studies investigating autism spectrum disorder (ASD) have focused on static brain function, but ignored the dynamic features of spontaneous brain activities in the temporal dimension. Research of dynamic brain regional activities might help to fully investigate the mechanisms of ASD patients. This study aimed to examine potential changes in the dynamic characteristics of regional neural activities in adult ASD patients and to detect whether the changes were associated with Autism Diagnostic Observation Schedule (ADOS) scores. Resting-state functional MRI was obtained on 77 adult ASD patients and 76 healthy controls. The dynamic regional homogeneity (dReHo) and dynamic amplitude of low-frequency fluctuations (dALFF) were compared between the two groups. Correlation analyses were also performed between dReHo and dALFF in areas showing group differences and ADOS scores. In ASD group, significant differences in dReHo were observed in the left middle temporal gyrus (MTG.L). Besides, we found increased dALFF in the left middle occipital gyrus (MOG.L), left superior parietal gyrus (SPG.L), left precuneus (PCUN.L), left inferior temporal gyrus (ITG.L), and right inferior frontal gyrus, orbital part (ORBinf.R). Furthermore, a significant positive correlation was found between dALFF in the PCUN.L and the ADOS_TOTAL scores, ADOS_SOCIAL scores; the dALFF in the ITG.L, SPG.L was positively associated with ADOS_SOCIAL scores. In conclusion, adults with ASD have a wide area of dynamic regional brain function abnormalities. These suggested that dynamic regional indexes might be used as a powerful measure to help us obtain a more comprehensive understanding of neural activity in adult ASD patients.

Paeonol, the active component of Cynanchum paniculatum, ameliorated schizophrenia-like behaviors by regulating the PI3K-Akt-GSK3β-NF-κB signalling pathway in MK-801-treated mice

ETHNOPHARMACOLOGICAL RELEVANCE

Cynanchum paniculatum (Bunge) Kitag. ex H. Hara (Asclepiadaceae) have been traditionally used in East Asia as analgesic or antiviral agents. Interestingly, some Chinese and Korean traditional medicinal books reported that the use of C. paniculatum in the treatment of psychotic symptoms, such as hallucinations and delusions.

AIM OF THE STUDY

In this study, we aimed to investigate whether C. paniculatum could improve sensorimotor gating disruption in mice with MK-801-induced schizophrenia-like behaviors. We also aimed to identify the active component of C. paniculatum that could potentially serve as a treatment for schizophrenia and found that paeonol, the major constituent compound of C. paniculatum, showed potential as a treatment for schizophrenia.

MATERIALS AND METHODS

To assess the effect of paeonol on mice with MK-801-induced schizophrenia-like behaviors, we carried out a series of behavioral tests related with symptoms of schizophrenia. In addition, we utilized Western blotting and ELISA techniques to investigate the antipsychotic actions of paeonol.

RESULT

C. paniculatum extract (100 or 300 mg/kg) and paenol (10 or 30 mg/kg) significantly reversed MK-801-induced prepulse deficits in acoustic startle response test. In addition, paeonol (10 or 30 mg/kg) attenuated social novelty preference and novel object recognition memory on MK-801-induced schizophrenia-like behaviour in mice. Furthermore, the phosphorylation levels of PI3K, Akt, GSK3β and NF-κB, as well as related pro-inflammatory cytokine, such as IL-1β and TNF-α, were significantly reversed by the administration of paeonol (10 or 30 mg/kg) in the prefrontal cortex of MK-801-treated mice.

CONCLUSIONS

Collectively, these data show that paeonol can potentially be used as an agent for treating sensorimotor gating deficits, negative symptoms, and cognitive deficits, such as those observed in schizophrenia with few adverse effects.