Neonatal Isolation Increases the Susceptibility to Learned Helplessness through the Aberrant Neuronal Activity in the Ventral Pallidum of Rats.

Objective: : Environmental deprivation, a type of childhood maltreatment, has been reported to constrain the cognitive developmental processes such as associative learning and implicit learning, which may lead to functional and morphological changes in the ventral pallidum (VP) and pessimism, a well-known cognitive feature of major depression. We examined whether neonatal isolation (NI) could influence the incidence of learned helplessness (LH) in a rat model mimicking the pessimism, and the number of vesicular glutamate transporter 2 (VGLUT2)-expressing VP cells and Penk-expressing VP cells. Methods: : The number of escape failures from foot-shocks in the LH test was measured to examine stress-induced depression-like behavior in rats. The number of VGLUT2-expressing VP cells and Penk-expressing VP cells was measured by immunohistochemistry. Results: : In NI rats compared with Sham rats, the incidence of LH in adulthood was increased and VGLUT2-expressing VP cells but not Penk-expressing VP cells in adulthood were decreased. VGLUT2-expressing VP cells were decreased only in the LH group of NI rats and significantly correlated with the escape latency in the LH test. Conclusion: : These findings suggest that the aberrant VP neuronal activity due to environmental deprivation early in life leads to pessimistic associative and implicit learning. Modulating VP neuronal activity could be a novel therapeutic and preventive strategy for the patients with this specific pathophysiology.

Long-term mental health and resilience of the first responders in Japanese ground self-defense forces engaging body recovery after the great east Japan earthquake.

Handling human remains is extremely difficult and stressful task, and it can contribute to the development of stress-related mental health problems. To prevent disaster from the development of mental disorders in first responders, it will be important to elucidate factors sustaining psychological well-being following the events requiring handling of human remains. Japanese Ground Self-Defense Forces (JGSDF) first responders (n = 146), involved in human remains recovery after the Great East Japan Earthquake (GEJE) participated. We examined the psychological resilience (S-H Resilience Test), depressive symptoms (SDS), and psychological distress (GHQ-28) 6 years after GEJE, in three groups; Group A: no contact no view of human remains, B: view only of human remains, and C: direct handling of human remains. S-H Resilience test evaluated the 3 subclasses of resilience; Social Support, Self Efficacy, Sociality. One-way ANOVA revealed the significant difference in resilience scores between Group B and C without any differences in depressive symptoms or psychological distress among the 3 groups. Multiple regression analyses revealed that depressive symptoms and resilience were associated with psychological distress in all participants. Path analyses showed that whereas one subtype of resilience indirectly reduced psychological distress through lower depressive symptoms in Group A (Social Support) and Group B (Sociality), both subtypes of resilience indirectly reduced psychological distress by lowering depressive symptoms in Group C. These findings suggest that exposure to higher stressful situation may decrease the psychological resilience based on the S-H Resilience test, and two subtypes of resilience may be necessary to sustain the psychological well-being.

Spike firing attenuation of serotonin neurons in learned helplessness rats is reversed by ketamine.

Animals suffering from uncontrollable stress sometimes show low effort to escape stress (learned helplessness). Changes in serotonin (5-hydroxytryptamine) signalling are thought to underlie this behaviour. Although the release of 5-hydroxytryptamine is triggered by the action potential firing of dorsal raphe nuclei 5-hydroxytryptamine neurons, the electrophysiological changes induced by uncontrollable stress are largely unclear. Herein, we examined electrophysiological differences among 5-hydroxytryptamine neurons in naïve rats, learned helplessness rats and rats resistant to inescapable stress (non-learned helplessness). Five-week-old male Sprague Dawley rats were exposed to inescapable foot shocks. After an avoidance test session, rats were classified as learned helplessness or non-learned helplessness. Activity-dependent 5-hydroxytryptamine release induced by the administration of high-potassium solution was slower in free-moving learned helplessness rats. Subthreshold electrophysiological properties of 5-hydroxytryptamine neurons were identical among the three rat groups, but the depolarization-induced spike firing was significantly attenuated in learned helplessness rats. To clarify the underlying mechanisms, potassium (K+) channels regulating the spike firing were initially examined using naïve rats. K+ channels sensitive to 500 µM tetraethylammonium caused rapid repolarization of the action potential and the small conductance calcium-activated K+ channels produced afterhyperpolarization. Additionally, dendrotoxin-I, a blocker of Kv1.1 (encoded by Kcna1), Kv1.2 (encoded by Kcna2) and Kv1.6 (encoded by Kcna6) voltage-dependent K+ channels, weakly enhanced the spike firing frequency during depolarizing current injections without changes in individual spike waveforms in naïve rats. We found that dendrotoxin-I significantly enhanced the spike firing of 5-hydroxytryptamine neurons in learned helplessness rats. Consequently, the difference in spike firing among the three rat groups was abolished in the presence of dendrotoxin-I. These results suggest that the upregulation of dendrotoxin-I-sensitive Kv1 channels underlies the firing attenuation of 5-hydroxytryptamine neurons in learned helplessness rats. We also found that the antidepressant ketamine facilitated the spike firing of 5-hydroxytryptamine neurons and abolished the firing difference between learned helplessness and non-learned helplessness by suppressing dendrotoxin-I-sensitive Kv1 channels. The dendrotoxin-I-sensitive Kv1 channel may be a potential target for developing drugs to control activity of 5-hydroxytryptamine neurons.

Chemogenetic activation of the mPFC alleviates impaired fear memory extinction in an animal model of PTSD.

BACKGROUND AND AIM: Although impaired extinction of fear memory (EFM) is a hallmark symptom of posttraumatic stress disorder (PTSD), the mechanisms underlying the impairment are unknown. Activation of the infralimbic cortex (IL) in the medial prefrontal cortex (mPFC) has been reported to predict successful fear extinction, whereas functionally disrupting this region impairs extinction. We examined whether chemogenetic activation of the IL could alleviate impaired EFM in a single prolonged stress (SPS) rat model of PTSD. METHODS: Chemogenetic activation of IL and prelimbic (PL) excitatory neurons was undertaken to evaluate EFM using a contextual fear conditioning paradigm. Neuronal activity in the IL was recorded using a 32-multichannel silicon electrode. To examine histological changes in the mPFC, apoptosis was measured by TUNEL staining. RESULTS: Chemogenetic activation of excitatory neurons in the IL, but not the PL, enhanced EFM in sham rats and resulted in alleviation of EFM impairment in SPS rats. The alleviation of impaired EFM in SPS rats was observed during the extinction test session. Neuronal activity in the IL of SPS rats was lower than that of sham rats after clozapine-n-oxide administration. Increased apoptosis was found in the IL of SPS rats. CONCLUSIONS: These findings suggest that a decreased excitatory response in the IL due, at least in part, to an increase in apoptosis in SPS rats leads to impaired EFM, and that neuronal activation during extinction training could be useful for the treatment of impaired EFM in PTSD patients.

The role of glucocorticoid receptors in the induction and prevention of hippocampal abnormalities in an animal model of posttraumatic stress disorder.

RATIONALE: Since the precise mechanisms of posttraumatic stress disorder (PTSD) remain unknown, effective treatment interventions have not yet been established. Numerous clinical studies have led to the hypothesis that elevated glucocorticoid levels in response to extreme stress might trigger a pathophysiological cascade which consequently leads to functional and morphological changes in the hippocampus. OBJECTIVES: To elucidate the pathophysiology of PTSD, we examined the alteration of hippocampal gene expression through the glucocorticoid receptor (GR) in the single prolonged stress (SPS) paradigm, a rat model of PTSD. METHODS: We measured nuclear GRs by western blot, and the binding of GR to the promoter of Bcl-2 and Bax genes by chromatin immunoprecipitation-qPCR as well as the expression of these 2 genes by RT-PCR in the hippocampus of SPS rats. In addition, we examined the preventive effects of a GR antagonist on SPS-induced molecular, morphological, and behavioral alterations (hippocampal gene expression of Bcl-2 and Bax, hippocampal apoptosis using TUNEL staining, impaired fear memory extinction (FME) using the contextual fear conditioning paradigm). RESULTS: Exposure to SPS increased nuclear GR expression and GR binding to Bcl-2 gene, and decreased Bcl-2 mRNA expression. Administration of GR antagonist immediately after SPS prevented activation of the glucocorticoid cascade, hippocampal apoptosis, and impairment FME in SPS rats. CONCLUSION: The activation of GRs in response to severe stress may trigger the pathophysiological cascade leading to impaired FME and hippocampal apoptosis. In contrast, administration of GR antagonist could be useful for preventing the development of PTSD.

Structural variation in the glycogen synthase kinase 3ß and brain-derived neurotrophic factor genes in Japanese patients with bipolar disorders.

BACKGROUND: Lithium is the first-line drug for the treatment of bipolar disorders (BDs); however, not all patients responded. Glycogen synthase kinase (GSK) 3ß and brain-derived neurotrophic factor (BDNF) play a role in the therapeutic action of lithium. Since structural variations were reported in these genes, it is possible that these genomic variations may be involved in the therapeutic responses to lithium. METHOD: Fifty patients with BDs and 50 healthy subjects (mean age 55.0 ± 15.0 years; M/F 19/31) participated. We examined structural variation of the GSK3ß and BDNF genes by real-time PCR. We examined the influence of structural variation of these genes on the therapeutic responses to lithium and the occurrence of antidepressant-emergent affective switch (AEAS). The efficacy of lithium was assessed using the Alda scale, and AEAS was evaluated using Young Mania Rating Scale. RESULTS: Although we examined structural variations within intron II and VII of the GSK3® gene and from the end of exon IV to intron IV and within exon IX of the BDNF gene, no structural variation was found in BDs. Whereas 5 of 50 patients exhibited three copies of the genomic region within exon IV of the BDNF gene, all healthy subjects had two copies. No difference in the therapeutic efficacy of lithium was found between patients with three and two copies. No difference in the occurrence of AEAS was found between the two groups. CONCLUSION: The amplification of the BDNF gene influenced neither the therapeutic responses to lithium nor the occurrence of AEAS.

Combined brain-derived neurotrophic factor with extinction training alleviate impaired fear extinction in an animal model of post-traumatic stress disorder.

Impaired fear memory extinction (Ext) is one of the hallmark symptoms of post-traumatic stress disorder (PTSD). However, since the precise mechanism of impaired Ext remains unknown, effective interventions have not yet been established. Recently, hippocampal-prefrontal brain-derived neurotrophic factor (BDNF) activity was shown to be crucial for Ext in naïve rats. We therefore examined whether decreased hippocampal-prefrontal BDNF activity is also involved in the Ext of rats subjected to a single prolonged stress (SPS) as a model of PTSD. BDNF levels were measured by enzyme-linked immunosorbent assay (ELISA), and phosphorylation of TrkB was measured by immunohistochemistry in the hippocampus and medial prefrontal cortex (mPFC) of SPS rats. We also examined whether BDNF infusion into the ventral mPFC or hippocampus alleviated the impaired Ext of SPS rats in the contextual fear conditioning paradigm. SPS significantly decreased the levels of BDNF in both the hippocampus and mPFC and TrkB phosphorylation in the ventral mPFC. Infusion of BDNF 24 hours after conditioning in the infralimbic cortex (ILC), but not the prelimbic cortex (PLC) nor hippocampus, alleviated the impairment of Ext. Since amelioration of impaired Ext by BDNF infusion did not occur without extinction training, it seems the two interventions must occur consecutively to alleviate impaired Ext. Additionally, BDNF infusion markedly increased TrkB phosphorylation in the ILC of SPS rats. These findings suggest that decreased BDNF signal transduction might be involved in the impaired Ext of SPS rats, and that activation of the BDNF-TrkB signal might be a novel therapeutic strategy for the impaired Ext by stress.

Musical disability in children with autism spectrum disorder.

Although enhanced musical ability is reported in individuals with autism spectrum disorders (ASD), this observation may be uncommon, and reports of auditory processing deficits suggest musical ability may be impaired. We hypothesized that musical ability would be impaired in children with ASD, that the severity of impairment would correlate with cognitive dysfunction, and with clinical features of illness. We evaluated 26 children with ASD and 27 typically developing (TD) children using the Montreal Battery of Evaluation of Amusia short version (MBEA-s) as well as cognitive tests and clinical evaluations of ASD symptomatology. Mean scores on the MBEA-s were significantly lower in children with ASD. MBEA-s scores did not correlate with cognitive test results in either ASD or TD children, and did not correlate with symptom severity in ASD children. For the ASD children only, the combination of hyperactivity/inattention and working memory resulted in a significant contribution to the variance in the MBEA-s score. The findings indicate that musical ability appears to be impaired in children with ASD, and assessment of musical ability may complement cognitive tests and measures of symptomatology in characterizing the shared neural substrates for these dysfunctions in ASD.

The influence of aging on the methylation status of brain-derived neurotrophic factor gene in blood.

OBJECTIVE: Brain-derived neurotrophic factor (BDNF) is involved in the pathophysiology of psychiatric disorders in adults and elderly individuals, and as a result, the DNA methylation (DNAm) of the BDNF gene in peripheral tissues including blood has been extensively examined to develop a useful biomarker for psychiatric disorders. However, studies to date have not previously investigated the effect of age on DNAm of the BDNF gene in blood. In this context, we measured DNAm of 39 CpG units in the CpG island at the promoter of exon I of the BDNF gene. METHODS: We analyzed genomic DNA from peripheral blood of 105 health Japanese women 20 to 80 years of age to identify aging-associated change in DNAm of the BDNF gene. In addition, we examined the relationship between total MMSE scores, numbers of stressful life events, and serum BDNF levels on DNAm of the BDNF gene. The DNAm rate at each CpG unit was measured using a MassArray® system (Agena Bioscience), and serum BDNF levels were measured by ELISA. RESULTS: There was a significant correlation between DNAm and age in 13 CpGs. However, there was no significant correlation between DNAm and total MMSE scores, numbers of life events, or serum BDNF levels. CONCLUSION: Despite the small number of subjects and the inclusion of only female subjects, our results suggest that DNAm of 13 CpGs of the BDNF gene may be an appropriate biomarker for aging and useful for predicting increased susceptibility to age-related psychiatric disorders.

Musical deficits and cortical thickness in people with schizophrenia.

Investigation of acquired amusia caused by brain damage suggested that cortical lesions of the right hemisphere contributed to musical deficits. We previously reported reduced musical ability in schizophrenia; these deficits were correlated with clinical manifestations such as cognitive dysfunction and negative symptoms. However, the neural substrate underlying the musical disability in schizophrenia remains unclear. We investigated the relationship between musical deficits and cortical thickness in patients with schizophrenia using structural MRI. We recruited 24 patients (13 males; age mean=45.9years old), and 22 controls (14 males, age mean=43.5years old). Musical ability was assessed with the Montreal Battery for Evaluation of Amusia (MBEA), cognitive function with the Brief Assessment of Cognition in Schizophrenia (BACS) and clinical features of illness with the Positive and Negative Syndrome Scale (PANSS). MRI Images were acquired and processed using FreeSurfer. Surface-based analysis showed that thinner cortex in left temporal and inferior frontal region was associated with lower musical ability in schizophrenia. In contrast, in controls thicker cortex in the left supramarginal region was correlated with lower musical ability. These results shed light on the clinical pathology underlying the associations of musical ability, cognitive dysfunction and negative symptoms in patients with schizophrenia.

Sex differences in auditory verbal hallucinations in early, middle and late adolescence: results from a survey of 17 451 Japanese students aged 12-18 years.

OBJECTIVES: Women have higher rates of auditory verbal hallucinations (AVH) than men; however, less is known about sex differences in the prevalence of AVH in early, middle and late adolescence. We sought to elucidate the differences in the prevalence of AVH and to examine the degree to which these differences could be explained by differences in levels of depressive symptoms. DESIGN: We used a cross-sectional design and a self-reported questionnaire. SETTING: Participants were recruited from public junior and senior high schools in Tsu, Mie Prefecture and Kochi Prefecture, Japan. PARTICIPANTS: In total, 19 436 students were contacted and 18 250 participated. Responses from 17 451 students with no missing data were analysed (aged 12-18 years, Mage=15.2 years (SD=1.7), 50.6% girls). MEASURES: AVH were assessed through one of four items adopted from the schizophrenia section of the Japanese version of the Diagnostic Interview Schedule for Children. Depressive symptoms were assessed using the 12-item General Health Questionnaire. RESULTS: The prevalence of AVH was 7.0% among early adolescents (aged 12-13 years), 6.2% among middle adolescents (aged 14-15 years) and 4.8% among late adolescents (aged 16-18 years). Being female was significantly associated with a higher prevalence of AVH through adolescence (OR=1.71, 95% CI 1.31 to 2.23 in early adolescence; OR=1.42, 95% CI 1.14 to 1.76 in middle adolescence; OR=1.52, 95% CI 1.23 to 1.87 in late adolescence); however, these differences became non-significant after adjusting for depressive symptoms (OR=1.21, 95% CI 0.92 to 1.60; OR=1.00, 95% CI 0.80 to 1.25; OR=1.16, 95% CI 0.93 to 1.44, respectively). CONCLUSIONS: Sex differences in auditory hallucinations are seen in both adult and youth populations. The higher rates of auditory verbal hallucinations seen in girls may be secondary to the differences in the rate of depressive symptoms.

Schizophrenia as a prodromal symptom in a patient harboring SNCA duplication.

We present the case of a patient who developed delusions and auditory hallucinations and was clinically diagnosed as having schizophrenia. Ten years after the onset of schizophrenia, the disease progressed to mild parkinsonism. SNCA duplication was confirmed. This case expands the spectrum of clinical features in carriers of SNCA duplication.

Cortical activation changes and sub-threshold affective symptoms are associated with social functioning in a non-clinical population: A multi-channel near-infrared spectroscopy study.

Few studies have examined the relationship between social function and brain activation in non-clinical populations. The aim of the present study was to assess this relationship and examine the underlying cortical mechanisms in a non-clinical population. Eighty healthy volunteers performed a serial arithmetic task according to the Uchida-Kraepelin performance test while hemoglobin concentration changes were assessed on the surface of the prefrontal cortex (PFC) using 32-channel near-infrared spectroscopy. Participants were also assessed for quality of life (QOL) using the Short-Form 36-item Questionnaire (SF-36), for affective symptoms using the Zung Self-rating Depression Scale (SDS), for apathy using the Apathy Scale, for feelings of stress using the Stress Arousal Checklist (SACL), and for task performance using the number of answers in a serial arithmetic task. Activity in the frontopolar PFC displayed a significant positive correlation with social functioning on the SF-36. SDS and SACL scores correlated negatively with social functioning. Furthermore, in multiple regression analysis, social functioning was predicted by activity of the frontopolar PFC and SDS scores. These results suggest that the association between changes in cortical activation and sub-threshold affective symptoms may objectively identify individuals with QOL on social functioning.

The potential use of histone deacetylase inhibitors in the treatment of depression.

Numerous preclinical studies demonstrate that changes in gene expression in the brain occur in animal models of depression using exposure to stress, such as social defeat and leaned helplessness, and that repeated administration of antidepressants ameliorates these stress-induced changes in gene expression. These findings suggest that alteration in gene transcription in the central nervous system in response to stress plays an important role in the pathophysiology of depression. Recent advances in epigenetics have led to the realization that chromatin remodeling mediated by histone deacetylase (HDAC) is closely involved in the regulation of gene transcription. In this context, we first review several preclinical studies demonstrating the antidepressant-like efficacy of HDAC inhibitors. We then suggest the efficacy of HDAC inhibitors in treatment-resistant depression based on the mechanism of action of HDAC. Finally, we discuss the possibility of using HDAC inhibitors in patients with treatment-resistant depression.

Comparing the driving behaviours of individuals with frontotemporal lobar degeneration and those with Alzheimer's disease.

BACKGROUND: Assessing driving aptitude in dementia patients is critically important for both patient and public safety. However, there have been only a few reports on the driving behaviours and accident risk of patients with dementia, especially frontotemporal lobar degeneration (FTLD). Therefore, we compared the characteristics of driving behaviours in patients with FTLD and those with Alzheimer's disease (AD). METHODS: The subjects were 28 FTLD and 67 AD patients who visited the Department of Psychiatry, Kochi Medical School Hospital. We conducted semi-structured interviews with their families and caregivers about traffic accident history and changes in patient driving behaviours after dementia onset and then compared the findings between the two groups. RESULTS: Overall changes in driving behaviours were reported in 89% (25/28) and 76% (51/67) of the FTLD and AD patients, respectively (P = 0.17). In the FTLD group, difficulty in judging inter-vehicle distances, ignoring road signs and traffic signals, and distraction were reported in 50% (14/28), 61% (17/28), and 50% (14/28) of patients, respectively, and 75% (21/28) patients had caused a traffic accident after dementia onset. The risk of causing an accident was higher in the FTLD group than in the AD group (odds ratio = 10.4, 95% confidence interval = 3.7-29.1). In addition, the mean duration between dementia onset and a traffic accident was 1.35 years in the FTLD group compared with 3.0 years in the AD group (P < 0.01). CONCLUSIONS: Patients with FTLD were more likely to show dangerous driving behaviours than those with AD, and the risk of causing a traffic accident may be higher in patients with FTLD from an early disease stage.

Blood diagnostic biomarkers for major depressive disorder using multiplex DNA methylation profiles: discovery and validation.

Aberrant DNA methylation in the blood of patients with major depressive disorder (MDD) has been reported in several previous studies. However, no comprehensive studies using medication-free subjects with MDD have been conducted. Furthermore, the majority of these previous studies has been limited to the analysis of the CpG sites in CpG islands (CGIs) in the gene promoter regions. The main aim of the present study is to identify DNA methylation markers that distinguish patients with MDD from non-psychiatric controls. Genome-wide DNA methylation profiling of peripheral leukocytes was conducted in two set of samples, a discovery set (20 medication-free patients with MDD and 19 controls) and a replication set (12 medication-free patients with MDD and 12 controls), using Infinium HumanMethylation450 BeadChips. Significant diagnostic differences in DNA methylation were observed at 363 CpG sites in the discovery set. All of these loci demonstrated lower DNA methylation in patients with MDD than in the controls, and most of them (85.7%) were located in the CGIs in the gene promoter regions. We were able to distinguish patients with MDD from the control subjects with high accuracy in the discriminant analysis using the top DNA methylation markers. We also validated these selected DNA methylation markers in the replication set. Our results indicate that multiplex DNA methylation markers may be useful for distinguishing patients with MDD from non-psychiatric controls.

The potential of SLC6A4 gene methylation analysis for the diagnosis and treatment of major depression.

We examined the utility of DNA methylation profiles at the CpG island of SLC6A4 (DMS) as a diagnostic biomarker for major depression (MD). In addition, the relationship between DMS and the serotonin transporter gene-linked polymorphic region (5-HTTLPR) allele, the severity of symptoms, number of early adversities, and therapeutic responses to antidepressants were examined. Genomic DNA was extracted from peripheral blood of Japanese healthy controls and patients with MD before and after treatment. DMS was analyzed using a MassARRAY Compact System. The severity of depression was evaluated using the Hamilton Rating Scale for Depression, and early adversity was evaluated using the Early Trauma Inventory. We were unable to distinguish between and healthy controls, or between unmedicated patients and medicated patients using DMS. The 5-HTTLPR allele had no significant effect on DMS. The methylation rates for several CpGs differed significantly after treatment. Notably, the methylation rate of CpG 3 in patients with better therapeutic responses was significantly higher than that in patients with poorer responses. Although further studies examining the function of specific CpG units of SLC6A4 are required, these results suggest that the pre-treatment methylation rate of SLC6A4 is associated with therapeutic responses to antidepressants in unmedicated patients with MD.

Electroconvulsive seizure induces thrombospondin-1 in the adult rat hippocampus.

Synaptic dysfunction has recently gained attention for its involvement in mood disorders. Electroconvulsive therapy (ECT) possibly plays a role in synaptic repair. However, the underlying mechanisms remain uncertain. Thrombospondin-1 (TSP-1), a member of the TSP family, is reported to be secreted by astrocytes and to regulate synaptogenesis. We investigated the effects of electroconvulsive seizure (ECS) on the expression of TSPs in the adult rat hippocampus. Single and repeated ECS significantly increased TSP-1 mRNA expression after 2h and returned to sham levels at 24h. Conversely, the TSP-2 and -4 mRNA levels did not change. Only repeated ECS induced TSP-1 proteins. ECS also induced glial fibrillary acidic protein (GFAP) expression. The GFAP expression occurred later than the TSP-1 mRNA expression following single ECS; however, it occurred earlier and was more persistent following repeated ECS. ECS had no effect on the α2δ-1 or neuroligin-1 expressions, both of which are TSP-1 receptors. Furthermore, chronic treatment with antidepressants did not induce the expression of TSP-1 or GFAP. These findings suggest that repeated ECS, but not chronic treatment with antidepressants, induces TSP-1 expression partially via the activation of astrocytes. Therefore, TSP-1 is possibly involved in the synaptogenic effects of ECS.