Association between stressful life events and sleep quality in Chinese university students: Mediating and moderating roles of emotion regulation.

This study investigated whether emotion regulation mediates or modulates the relationship of SLEs with sleep quality and potential sex differences. A total of 1447 Chinese university students completed the Adolescent Self-Rating Life Events Checklist, the Pittsburgh Sleep Quality Index, and the Emotion Regulation Questionnaire. The results indicated that both cognitive reappraisal and expressive suppression significantly mediated and moderated the negative association between SLEs and sleep quality. Additionally, sex differences were found for the mediating role of cognitive reappraisal and for the modulating roles of cognitive reappraisal and expressive suppression in the relationship between SLEs and sleep quality. Although the present cross-sectional data does not allow us to test any causal relationships, these results help clarify the underlying emotion-regulation process between SLEs and sleep in university students and highlight the importance of considering sex differences in emotion regulation.

Chinese version of the Perth Alexithymia Questionnaire: psychometric properties and clinical applications.

Background: The alexithymia trait is of high clinical interest. The Perth Alexithymia Questionnaire (PAQ) was recently developed to enable detailed facet-level and valence-specific assessments of alexithymia. Aims: In this paper, we introduce the first Chinese version of the PAQ and examine its psychometric properties and clinical applications. Methods: In Study 1, the PAQ was administered to 990 Chinese participants. We examined its factor structure, internal consistency, test-retest reliability, as well as convergent, concurrent and discriminant validity. In Study 2, four groups, including a major depressive disorder (MDD) group (n=50), a matched healthy control group for MDD (n=50), a subclinical depression group (n=50) and a matched healthy control group for subclinical depression (n=50), were recruited. Group comparisons were conducted to assess the clinical relevance of the PAQ. Results: In Study 1, the intended five-factor structure of the PAQ was found to fit the data well. The PAQ showed good internal consistency and test-retest reliability, as well as good convergent, concurrent and discriminant validity. In Study 2, the PAQ was able to successfully distinguish the MDD group and the subclinical depression group from their matched healthy controls. Conclusions: The Chinese version of the PAQ is a valid and reliable instrument for comprehensively assessing alexithymia in the general population and adults with clinical/subclinical depression.

Cross-cultural adaptation and clinical application of the Perth Empathy Scale.

OBJECTIVE: Alterations of empathy have been observed in patients with various mental disorders. The Perth Empathy Scale (PES) was recently developed to measure a multidimensional construct of empathy across positive and negative emotions. However, its psychometric properties and clinical applications have not been examined in the Chinese context. METHODS: The Chinese version of the PES was developed and administered to a large Chinese sample (n = 1090). Factor structure, internal consistency, test-retest reliability, and convergent, discriminant, as well as concurrent validity were examined. Moreover, 50 patients with major depressive disorder (MDD) and 50 healthy controls were recruited to explore the clinical utility of the PES. RESULTS: Confirmatory factor analyses supported a theoretically congruent three-factor structure of empathy, namely Cognitive Empathy, Negative Affective Empathy and Positive Affective Empathy. The PES showed good to excellent internal consistency reliability, good convergent and discriminant validity, acceptable concurrent validity, and moderate to high test-retest reliability. Patients with MDD had significantly lower PES scores compared to healthy controls. Linear discriminant function comprised of the three factors correctly differentiated 71% of participants, which further verified the clinical utility of the PES. CONCLUSIONS: Our findings indicated that the Chinese version of the PES is a reliable and valid instrument to measure cognitive and affective empathy across negative and positive emotions, and could therefore be used in both research and clinical practice.

Early Gray Matter Structural Covariance Predicts Longitudinal Gain in Arithmetic Ability in Children.

Previous neuroimaging studies on arithmetic development have mainly focused on functional activation or functional connectivity between brain regions. It remains largely unknown how brain structures support arithmetic development. The present study investigated whether early gray matter structural covariance contributes to later gain in arithmetic ability in children. We used a public longitudinal sample comprising 63 typically developing children. The participants received structural magnetic resonance imaging scanning when they were 11 years old and were tested with a multiplication task at 11 years old (time 1) and 13 years old (time 2), respectively. Mean gray matter volumes were extracted from eight brain regions of interest to anchor salience network (SN), frontal-parietal network (FPN), motor network (MN), and default mode network (DMN) at time 1. We found that longitudinal gain in arithmetic ability was associated with stronger structural covariance of the SN seed with frontal and parietal regions and stronger structural covariance of the FPN seed with insula, but weaker structural covariance of the FPN seed with motor and temporal regions, weaker structural covariance of the MN seed with frontal and motor regions, and weaker structural covariance of the DMN seed with temporal region. However, we did not detect correlation between longitudinal gain in arithmetic ability and behavioral measure or regional gray matter volume at time 1. Our study provides novel evidence for a specific contribution of gray matter structural covariance to longitudinal gain in arithmetic ability in childhood.

Associations between physical activity and proactive control and the modulating role of working memory.

Accumulating evidence indicates positive associations between physical activity (PA) and cognitive control. Proactive control, the ability to maintain goal-relevant information in preparation of upcoming task demands, is a critical component of cognitive control. However, little research has examined the association between PA and proactive control. To address this issue, a total of 132 university students were recruited and divided into two groups based on reported regular PA during past week. All participants completed two common cognitive control tasks: the AX Continuous Performance Task (AX-CPT) and the Cued Task-Switching Paradigm (CTS). In comparison with the low PA group, the high PA group showed greater proactive control efficiency on both tasks. Moreover, proactive control indices significantly correlated between the two tasks for the high but not for the low PA group. Further, working memory significantly modulated the association between PA and proactive control efficiency of CTS. Although the present cross-section design does not allow us to test the causal relationship between PA and proactive control, these findings may have important implications for developing effective intervention strategies which aim to promote proactive control through increasing PA or to promote PA through increasing proactive control. Moreover, individual differences in working memory are important to consider when we aim to design such interventions.

Negative emotion amplifies retrieval practice effect for both task-relevant and task-irrelevant information.

Selective retrieval of task-relevant information often facilitates memory retention of that information. However, it is still unclear if selective retrieval of task-relevant information can alter memory for task-irrelevant information, and the role of emotional arousal in it. In two experiments, we used emotional and neutral faces as stimuli, and participants were asked to memorise the name (who is this person?) and location (where does he/she come from?) associated with each face in initial study. Then, half of the studied faces were presented as cues, and participants were asked to retrieve the corresponding names (Experiment 1) or locations (Experiment 2). Finally, all the faces were presented and participants were asked to retrieve both the corresponding names and locations. The results of the final test showed that retrieval practice not only enhanced memory of task-relevant information but also enhanced memory of task-irrelevant information. More importantly, negative emotion amplified the retrieval practice effect overall, with a larger retrieval-induced benefit for the negative than neutral condition. These findings demonstrated an emotional arousal amplification effect on retrieval-induced enhancement effects, suggesting that the advantage of the retrieved memory representations can be amplified by emotional arousal even without explicit goals in a task setting.

Microglia are involved in regulating histamine-dependent and non-dependent itch transmissions with distinguished signal pathways.

Although itch and pain have many similarities, they are completely different in perceptual experience and behavioral response. In recent years, we have a deep understanding of the neural pathways of itch sensation transmission. However, there are few reports on the role of non-neuronal cells in itch. Microglia are known to play a key role in chronic neuropathic pain and acute inflammatory pain. It is still unknown whether microglia are also involved in regulating the transmission of itch sensation. In the present study, we used several kinds of transgenic mice to specifically deplete CX3CR1+ microglia and peripheral macrophages together (whole depletion), or selectively deplete microglia alone (central depletion). We observed that the acute itch responses to histamine, compound 48/80 and chloroquine were all significantly reduced in mice with either whole or central depletion. Spinal c-fos mRNA assay and further studies revealed that histamine and compound 48/80, but not chloroquine elicited primary itch signal transmission from DRG to spinal Npr1- and somatostatin-positive neurons relied on microglial CX3CL1-CX3CR1 pathway. Our results suggested that microglia were involved in multiple types of acute chemical itch transmission, while the underlying mechanisms for histamine-dependent and non-dependent itch transmission were different that the former required the CX3CL1-CX3CR1 signal pathway.

Effects of rearing systems on the eggshell quality, bone parameters and expression of genes related to bone remodeling in aged laying hens.

Public concerns regarding animal welfare are changing the selection of rearing systems in laying hens. This study investigated the effects of rearing systems on eggshell quality, bone parameters and relative expression levels of genes related to bone remodeling in aged laying hens. A total of 2,952 55-day-old Jing Tint Six pullets were randomly assigned to place in the conventional caging system (CCS) or aviary system (AVS) and kept until 95 weeks of age. The AVS group delayed the decrease of eggshell quality and alleviated the symptoms of osteoporosis in the humerus rather than in the femur. Eggshell breaking strength, thickness, weight, weight ratio, stiffness and fracture toughness were decreased linearly with age (from 55 to 95 weeks of age, p < 0.05). The AVS group had higher eggshell breaking strength, stiffness and fracture toughness than the CCS group (p < 0.05). Higher total calcium and phosphorus per egg were presented in the AVS group at 95 weeks of age (p < 0.05). At 95 weeks of age, the AVS group had a humerus with higher weight, volume, length, midpoint perimeter, cortical index, fat-free dry weight, ash content, total calcium per bone, total phosphorus per bone, average bone mineral density, strength, stiffness and work to fracture compared to the CCS group (p < 0.05). Such differences did not appear in the femur. The relative expression levels of alkaline phosphatase (ALP) and osteocalcin (OCN) genes in the femur and hormone receptors (vitamin D receptor (VDR), estrogen receptor alpha (ERα) and fibroblast growth factor 23 (FGF23)) genes in the humerus were significantly upregulated (p < 0.05) in the AVS group. The level of tartrate-resistant acid phosphatase (TRAP) transcripts was also increased (p < 0.05) in the femur of the AVS group. Overall, compared with the CCS, the AVS alleviated the deterioration of eggshell and bone qualities of aged laying hens, which may be related to the changes in the expression of genes associated with bone remodeling.

The longitudinal development of large-scale functional brain networks for arithmetic ability from childhood to adolescence.

Arithmetic ability is an important high-level cognitive function that requires interaction among multiple brain regions. Previous studies on arithmetic development have focused on task-induced activation in isolated brain regions or functional connectivity among particular seed regions. However, it remains largely unknown whether and how functional connectivity among large-scale brain modules contributes to arithmetic development. In the present study, we used a longitudinal sample of task-based functional magnetic resonance imaging (fMRI) data comprising 63 typically developing children, with two testing points being about 2 years apart. With graph theory, we examined the longitudinal development of large-scale brain modules for a multiplication task in younger (mean age 9.88 at time 1) and older children (mean age 12.34 at time 1), respectively. The results showed that the default-mode (DMN) and frontal-parietal networks (FPN) became increasingly segregated over time. Specifically, intra-connectivity within the DMN and FPN increased significantly with age, and inter-connectivity between the DMN and visual network decreased significantly with age. Such developmental changes were mainly observed in the younger children but not in the older children. Moreover, the change in network segregation of the DMN was positively correlated with longitudinal gain in arithmetic performance in the younger children, and individual difference in network segregation of the FPN was positively correlated with arithmetic performance at Time 2 in the older children. Taken together, the present results highlight the development of the functional architecture in large-scale brain networks from childhood to adolescence, which may provide insights into potential neural mechanisms underlying arithmetic development.

Presynaptic HCN channels constrain GABAergic synaptic transmission in pyramidal cells of the medial prefrontal cortex.

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are widely expressed in neurons in the central nervous system. It has been documented that HCN channels regulate the intrinsic excitability of pyramidal cells in the medial prefrontal cortex (mPFC) of rodents. Here, we report that HCN channels limited GABAergic transmission onto pyramidal cells in rat mPFC. The pharmacological blockade of HCN channels resulted in a significant increase in the frequency of both spontaneous and miniature inhibitory postsynaptic currents (IPSCs) in mPFC pyramidal cells, whereas potentiation of HCN channels reversely decreases the frequency of mIPSCs. Furthermore, such facilitation effect on mIPSC frequency required presynaptic Ca2+ influx. Immunofluorescence staining showed that HCN channels expressed in presynaptic GABAergic terminals, as well as in both soma and neurite of parvalbumin-expressing (PV-expressing) basket cells in mPFC. The present results indicate that HCN channels in GABAergic interneurons, most likely PV-expressing basket cells, constrain inhibitory control over layer 5-6 pyramidal cells by restricting presynaptic Ca2+ entry.

Polygalasaponin F protects hippocampal neurons against glutamate-induced cytotoxicity.

Excess extracellular glutamate leads to excitotoxicity, which induces neuronal death through the overactivation of N-methyl-D-aspartate receptors (NMDARs). Excitotoxicity is thought to be closely related to various acute and chronic neurological disorders, such as stroke and Alzheimer's disease. Polygalasaponin F (PGSF) is a triterpenoid saponin monomer that can be isolated from Polygala japonica, and has been reported to protect cells against apoptosis. To investigate the mechanisms underlying the neuroprotective effects of PGSF against glutamate-induced cytotoxicity, PGSF-pretreated hippocampal neurons were exposed to glutamate for 24 hours. The results demonstrated that PGSF inhibited glutamate-induced hippocampal neuron death in a concentration-dependent manner and reduced glutamate-induced Ca2+ overload in the cultured neurons. In addition, PGSF partially blocked the excess activity of NMDARs, inhibited both the downregulation of NMDAR subunit NR2A expression and the upregulation of NMDAR subunit NR2B expression, and upregulated the expression of phosphorylated cyclic adenosine monophosphate-responsive element-binding protein and brain-derived neurotrophic factor. These findings suggest that PGSF protects cultured hippocampal neurons against glutamate-induced cytotoxicity by regulating NMDARs. The study was approved by the Institutional Animal Care Committee of Nanchang University (approval No. 2017-0006) on December 29, 2017.

DSCAM Deficiency Leads to Premature Spine Maturation and Autism-like Behaviors.

Mutations in some cell adhesion molecules (CAMs) cause abnormal synapse formation and maturation, and serve as one of the potential mechanisms of autism spectrum disorders (ASDs). Recently, DSCAM (Down syndrome cell adhesion molecule) was found to be a high-risk gene for autism. However, it is still unclear how DSCAM contributes to ASD. Here, we show that DSCAM expression was downregulated following synapse maturation, and that DSCAM deficiency caused accelerated dendritic spine maturation during early postnatal development. Mechanistically, the extracellular domain of DSCAM interacts with neuroligin1 (NLGN1) to block the NLGN1-neurexin1ß (NRXN1ß) interaction. DSCAM extracellular domain was able to rescue spine overmaturation in DSCAM knockdown neurons. Precocious spines in DSCAM-deficient mice showed increased glutamatergic transmission in the developing cortex and induced autism-like behaviors, such as social novelty deficits and repetitive behaviors. Thus, DSCAM might be a repressor that prevents premature spine maturation and excessive glutamatergic transmission, and its deficiency could lead to autism-like behaviors. Our study provides new insight into the potential pathophysiological mechanisms of ASDs.SIGNIFICANCE STATEMENTDSCAM is not only associated with Down syndrome but is also a strong autism risk gene based on large-scale sequencing analysis. However, it remains unknown exactly how DSCAM contributes to autism. In mice, either neuron- and astrocyte-specific or pyramidal neuron-specific DSCAM deficiencies resulted in autism-like behaviors and enhanced spatial memory. In addition, DSCAM knockout or knockdown in pyramidal neurons led to increased dendritic spine maturation. Mechanistically, the extracellular domain of DSCAM binds to NLGN1 and inhibits NLGN1-NRXN1ß interaction, which can rescue abnormal spine maturation induced by DSCAM deficiency. Our research demonstrates that DSCAM negatively modulates spine maturation, and that DSCAM deficiency leads to excessive spine maturation and autism-like behaviors, thus providing new insight into a potential pathophysiological mechanism of autism.

Alleviation of Anxiety/Depressive-Like Behaviors and Improvement of Cognitive Functions by Lactobacillus plantarum WLPL04 in Chronically Stressed Mice.

BACKGROUND: Intestinal microorganisms play an important role in regulating the neurodevelopment and the brain functions of the host through the gut-brain axis. Lactobacillus, one of the most representative intestinal probiotics, produces important effects on human physiological functions. Our previous studies reveal that the Lactobacillus plantarum WLPL04 has a series of beneficial actions, such as antiadhesion of pathogens, protection from the harmful effect of sodium dodecyl sulfate, and anti-inflammatory stress on Caco2 cells. However, its effects on brain functions remain unknown. The present study aims to evaluate the potential effect of L. plantarum WLPL04 on anxiety/depressive-like behaviors in chronically restrained mice. METHODS: Newly weaned mice were exposed to chronic restraint stress for four weeks and raised daily with or without L. plantarum WLPL04 water supplement. Animals were behaviorally assessed for anxiety/depression and cognitive functions. The 16S rRNA sequencing was performed to analyze the intestinal microbiota structure. The levels of the medial prefrontal cortical (mPFC) brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) and serum 5-hydroxytryptamine (5-HT) were examined using Western blot and enzyme-linked immunosorbent assay. RESULTS: The chronic stress-induced anxiety/depressive-like behaviors and cognitive deficits were significantly alleviated by the L. plantarum WLPL04 treatment. The 16S rRNA sequencing analysis showed that the chronic stress reduced the diversity and the richness of intestinal microbiota, which were rescued by the L. plantarum WLPL04 treatment. The levels of BDNF and TrkB in the mPFC and the concentration of 5-HT in the serum remained unchanged in chronically restrained mice treated with the L. plantarum WLPL04. CONCLUSIONS: The L. plantarum WLPL04 can rescue anxiety/depressive-like behaviors and cognitive dysfunctions, reverse the abnormal change in intestinal microbiota, and alleviate the reduced levels of 5-HT, BDNF, and TrkB induced by chronic stress in mice, providing an experimental basis for the therapeutic application of L. plantarum on anxiety/depression.

[Advances in studies on structure and pharmacological activities of natural tirucallane-type triterpenoids].

The tirucallane-type triterpenoids, composed of six isoprene units, belong to a group of tetracyclic triterpenoids. Although the naturally-derived tirucallane-type triterpenoids were found in a small amount, the kind of compounds showed various structures, which consist of apo-type, linear said-chain-type and cyclolike said-chain-type and broad bioactivities, such as cytotoxicity, anti-inflammation, antioxidation and anti-plasmin, etc. This paper summarized origins, structures and bioactivities of tirucallane-type triterpenoids in recent ten years. The future research and exploration of tirucallane-type triterpenoids were discussed and prospected.

Efficacy of surgery for the treatment of astrocytoma: A protocol of systematic review and meta-analysis.

BACKGROUND: This study will assess the efficacy of surgery for the treatment of patients with astrocytoma. METHODS: We will undertake searches for randomized controlled trials from the following databases: MEDLINE, EMBASE, Cochrane Library, CINAHL, PsycINFO, and China National Knowledge Infrastructure. We will search all these databases from their inception to the March 1, 2020. No language limitation and publication status will be imposed in this study. Two authors will independently carry out study selection, data extraction, and study quality assessment. We will invite another author to solve any divergences between 2 authors. We will use RevMan 5.3 software to conduct statistical analysis. RESULTS: This study will present synthesis of most recent evidence of surgery for the treatment of patients with astrocytoma. CONCLUSION: The findings of this study will provide helpful reference for the efficacy and complications of surgery for the treatment of patients with astrocytoma to the clinicians and future researchers. STUDY REGISTRATION: INPLASY202040194.

NRG1-ErbB4 signaling promotes functional recovery in a murine model of traumatic brain injury via regulation of GABA release.

Traumatic brain injury (TBI) is a serious health problem in the world. However, little is known about the pathogenesis and molecular mechanisms of TBI. Here, we show that TBI activates neuregulin 1 (NRG1)-ErbB4 signaling, with an increased expression of NRG1 and ErbB4 in the traumatic region. Specifically knocking out ErbB4 in parvalbumin-positive (PV+) interneurons exacerbates motor function deficits in mice after TBI. Consistently, PV-ErbB4-/- mice showed larger necrotic area and more edema when compared with PV-ErbB4+/+ mice. Replenishment of NRG1 through intranasal application of the recombinant protein in PV-ErbB4+/+ mice enhanced neurological function. Moreover, using an in vitro neuronal culture system, we found that NRG1-ErbB4 signaling protects neurons from glutamate-induced death, and such protective effects could be diminished by GABA receptor antagonist. These results indicate that NRG-ErbB4 signaling protects cortical neurons from TBI-induced damage, and such effect is probably mediated by promoting GABA activity. Taken together, these findings unveil a previously unappreciated role for NRG1-ErB4 signaling in preventing neuronal cell death during functional recovery after TBI.

Voluntary wheel running promotes myelination in the motor cortex through Wnt signaling in mice.

Myelin of the central nervous system exhibits strong plasticity, and skill learning exercise promotes oligodendrogenesis and adaptive myelination. Increasing evidence shows that brain structures and functions are affected by physical activity. However, the impact of voluntary physical activity on central myelination and its underlying mechanism remains unclear. The present study aimed to investigate the effect of voluntary wheel running (VWR) on central oligodendrogenesis and adaptive myelination in mice. Adult C57BL/6 J mice were placed in running wheels and allowed for voluntary running 2 weeks. Myelin levels in the central nervous system were detected using western blotting, qRT-PCR, immunohistochemical staining, and electron microscopy. Oligodendrocyte precursor cells (OPCs) and oligodendrocytes (OLs) were detected using immunohistochemical staining and 5-bromo-2-deoxyuridine (BrdU) assays. Motor abilities of the animals were examined using open-field, rotarod running, and beam-walking behavioral paradigms. Vital molecules of Wnt signaling were detected, and the involvement of such molecules was verified using in vitro culture of OPCs. Our results showed that VWR significantly enhanced the myelination in the motor cortex. VWR promoted the proliferation and differentiation of OPCs, and the maturation of OLs. The VWR-regulated myelination was associated with the improved motor skill and decreased mRNA level of Wnt3a/9a, whereas stimulation of Wnt signaling pathway with Wnt3a or Wnt9a suppressed OPCs proliferation and differentiation in vitro. The present study demonstrated that physical activity is highly efficient at promoting myelination in the motor cortex, by enhancing the proliferation of OPCs and accelerating the generation of myelin, providing a step forward in understanding the beneficial effects of physical activity on central myelination and its underlying mechanism.

[Reviews on natural monocyclic sesquiterpenoids and their bioactivities].

Sesquiterpenes are a class of terpenoids composed of three isoprene units( 15 carbons). Sesquiterpenoids possess a variety of different structures,including acyclic sesquiterpenes,monocyclic sesquiterpenoids,bicyclic sesquiterpenoids,tricyclic sesquiterpenoids,tetracyclic sesquiterpenoids and macrocyclic sesquiterpenoids. Among them,a large number of monocyclic sesquiterpenoids were isolated and display extensive bioactivities,such as cytotoxic,antioxidant,anti-inflammatory,antibacterial and other activities. In this review,we summarized the progress about the phytochemistry and biological activities of monocyclic sesquiterpenoids( a total of161 compounds) reported from 2014 to 2018( 5 years),including megastigmanes,monocyclofarnesol-type,bisabolane-type,germacrane-type,and other types of monocyclic sesquiterpenoids. Furthermore,several future research perspectives and development of sesquiterpenoids as potential therapeutic agents were discussed as well.