Detection of differential selection pressure and functional-specific sites in subunits of vertebrate neuronal nicotinic acetylcholine receptors.

The nicotinic acetylcholine receptors (nAChR) are made of subunits evolved from a common ancestor. Despite the similarity in their sequences and structures, the properties of these subunits vary significantly. Thus, identifying the evolution features and function-related sites specific to each subunit is essential for understanding the characteristics of the subunits and the receptors assembled by them. In this study, we examined the sequence features of the nine neuronal nAChRs subunits from representative vertebrate species. Analysis revealed that all the subunits were subject to strong purifying selection in evolution, and each was under a unique pattern of selection pressures. At the same time, the functional constraints were not uniform within each subunit, with different domains in the molecule being subject to different selection pressures. We also detected potential positive selection events in the subunits or subunit clusters, and identified the sites might be associated with the function specificity of each subunit. Furthermore, positive selection at some domains might contribute to the diversity of subunit function; for example, the ß9 strand might be related to the agonist specificity of α subunit in heteromeric receptor and ß4-ß5 linker could be involved in Ca2+ permeability. Subunits α7, α4 and ß2 subunits possess a strong adaptability in vertebrates. Our results highlighted the importance of tracking functional differentiation in protein sequence underlying functional properties of nAChRs. In summary, our work may provide clues on understanding the diversity and the function specificity of the nAChR subunits, as well as the receptors co-assembled by them.Communicated by Ramaswamy H. Sarma.

Evolutionary Changes in Pathways and Networks of Genes Expressed in the Brains of Humans and Macaques.

As the key organ that separates humans from nonhuman primates, the brain has continuously evolved to adapt to environmental and climatic changes. Although humans share most genetic, molecular, and cellular features with other primates such as macaques, there are significant differences in the structure and function of the brain between humans and these species. Thus, exploring the differences between the brains of human and nonhuman primates in the context of evolution will provide insights into the development, functionality, and diseases of the human central nervous system (CNS). Since the genes involved in many aspects of the human brain are under common pressures of natural selection, their evolutionary features can be analyzed collectively at the pathway level. In this study, the molecular mechanisms underlying human brain capabilities were explored by comparing the evolution features of pathways enriched in genes expressed in the human brain and the macaque brain. We identified 31 pathways with differential evolutionary properties, including those related to neurological diseases, signal transduction, immunological response, and metabolic processes. By analyzing genes differentially expressed in brain regions or development stages between humans and macaques,  9 and 4 pathways with differential evolutionary properties were detected, respectively. We further performed crosstalk analysis on the pathways to obtain an intuitive correlation between the pathways, which is helpful in understanding the mechanisms of interaction between pathways. Our results provide on a comprehensive view of the evolutionary pathways of the human CNS and can serve as a reference for the study of human brain development.

Corrigendum to "Hydrogen Gas Attenuates Hypoxic-Ischemic Brain Injury via Regulation of the MAPK/HO-1/PGC-1a Pathway in Neonatal Rats".

[This corrects the article DOI: 10.1155/2020/6978784.].

SP1 activated-lncRNA SNHG1 mediates the development of epilepsy via miR-154-5p/TLR5 axis.

BACKGROUND: Epilepsy is a one of the most frequent serious neurological disorders characterized by enduring and unprovoked seizures. The treatments to epilepsy are very limited and many patients are even resistant to current medications due to the elusive pathogenesis. Here, we sought to investigate the functions of lncRNA SNHG1 and miR-154-5p in epilepsy. METHODS: We employed both in vivo mouse model and in vitro cell model to study epilepsy. H&E staining and Nissl staining were used to examine the morphology of hippocampus and measure neuronal injury, respectively. TUNEL staining and flow cytometry were performed to determine cell apoptosis. Caspase-3 activity assay kit was used to assess caspase-3 activity. RT-qPCR and western blot were conducted to measure the levels of SNHG1, miR-154-5p, TLR5, and SP1, respectively. Dual luciferase reporter assay was employed to validate the binding relationship of SNHG1/miR-154-5p and miR-154-5p/TLR5. ChIP assay was performed to confirm the transcriptional regulation of SP1 on SNHG1. RESULTS: Elevated SNHG1 and decreased miR-154-5p were observed in both in vivo mouse model and in vitro cell model of epilepsy. Knockdown of SNHG1 or transfection with miR-154-5p mimics significantly ameliorated Mg2+ free-induced neuronal injury in SH-SY5Y cells. SNHG1 acted as a sponge of miR-154-5p. Moreover, SNHG1 promoted neuronal injury via acting as a miR-154-5p sponge to disinhibit TLR5. Additionally, SP1 activated the transcriptional activity of SNHG1. CONCLUSION: In summary, SP1 transcriptionally activated-SNHG1 contributes to the development of epilepsy via directly regulating miR-154-5p/TLR5 axis, which provides novel targets in treatment of epilepsy.

Hydrogen Gas Attenuates Hypoxic-Ischemic Brain Injury via Regulation of the MAPK/HO-1/PGC-1a Pathway in Neonatal Rats.

Neonatal hypoxic-ischemic encephalopathy (HIE) is a leading cause of death in neonates with no effective treatments. Recent advancements in hydrogen (H2) gas offer a promising therapeutic approach for ischemia reperfusion injury; however, the impact of this approach for HIE remains a subject of debate. We assessed the therapeutic effects of H2 gas on HIE and the underlying molecular mechanisms in a rat model of neonatal hypoxic-ischemic brain injury (HIBI). H2 inhalation significantly attenuated neuronal injury and effectively improved early neurological outcomes in neonatal HIBI rats as well as learning and memory in adults. This protective effect was associated with initiation time and duration of sustained H2 inhalation. Furthermore, H2 inhalation reduced the expression of Bcl-2-associated X protein (BAX) and caspase-3 while promoting the expression of Bcl-2, nuclear factor erythroid-2-related factor 2, and heme oxygenase-1 (HO-1). H2 activated extracellular signal-regulated kinase and c-Jun N-terminal protein kinase and dephosphorylated p38 mitogen-activated protein kinase (MAPK) in oxygen-glucose deprivation/reperfusion (OGD/R) nerve growth factor-differentiated PC12 cells. Inhibitors of MAPKs blocked H2-induced HO-1 expression. HO-1 small interfering RNA decreased the expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and sirtuin 1 (SIRT1) and reversed the protectivity of H2 against OGD/R-induced cell death. These findings suggest that H2 augments cellular antioxidant defense capacity through activation of MAPK signaling pathways, leading to HO-1 expression and subsequent upregulation of PGC-1α and SIRT-1 expression. Thus, upregulation protects NGF-differentiated PC12 cells from OGD/R-induced oxidative cytotoxicity. In conclusion, H2 inhalation exerted protective effects on neonatal rats with HIBI. Early initiation and prolonged H2 inhalation had better protective effects on HIBI. These effects of H2 may be related to antioxidant, antiapoptotic, and anti-inflammatory responses. HO-1 plays an important role in H2-mediated protection through the MAPK/HO-1/PGC-1α pathway. Our results support further assessment of H2 as a potential therapeutic for neurological conditions in which oxidative stress and apoptosis are implicated.

LncRNA UCA1 Suppresses the Inflammation Via Modulating miR-203-Mediated Regulation of MEF2C/NF-κB Signaling Pathway in Epilepsy.

Although many advances have been made in the pathogenesis of epilepsy recently, the pathological mechanisms of epilepsy are still largely unknown. Exploring the pathological mechanisms and developing novel therapeutic strategies for epilepsy are urgently needed. A SD rat model of epilepsy was established with lithium chloride-pilocarpine. Astrocytes were isolated, cultured from 8 to 12 week rats and identified by flow cytometry and immunofluorescence. Immunohistochemical staining was used for MEF2C and NF-κB in paraffin-embedded sections. RT-qPCR and western blot were used to analyze gene expression. ELISA was used to analyze the concentration of IL-6, TNF-α and Cox-2. Cells were transfected with pcDNA-MEFC2, sh-MEFC2, pcDNA-UCA1, sh-UCA1, miR-203 mimic or miR-203 inhibitor. Cell viability was assessed by MTT assay. Dual luciferase assay was used to determine the direct interaction of lncRNA UCA1/miR-203 and miR-203/MEF2C. MEF2C was down-regulated and inhibited NF-κB expression and the secretion of IL-6 and TNF-α in epilepsy. LncRNA UCA1 was also down-regulated in epilepsy. LncRNA UCA1 over-expression increased the expression of MEF2C and its knock-down decreased MEF2C expression. Luciferase activity showed lncRNA UCA1 directly targeted miR-203 and miR-203 directly targeted MEF2C. MiR-203 suppressed the expression of MEF2C, and promoted NF-κB, phosphorylated IκB/IKK and inflammatory effectors, which was reversed by MEF2C knock-down. Moreover, lncRNA UCA1 could increase the expression of MEF2C to inhibit NF-κB, phosphorylated IκB/IKK and inflammatory effectors, which was also reversed by miR-203 mimic transfection. LncRNA UCA1 inhibited the inflammation via regulating miR-203 mediated regulation of MEF2C/NF-κB signaling in epilepsy. Our investigation elucidated novel pathological mechanisms and provided potential therapeutic targets for epilepsy.

Association of Helicobacter pylori Infection with Vitamin D Deficiency in Infants and Toddlers.

Helicobacter pylori (H. pylori), a gram-negative pathogen, has been shown to colonize multiple organs and cause various forms of extra-gastrointestinal diseases. The association of H. pylori infection with vitamin D status in apparently healthy children remained unclear; therefore, we investigated the relationship between vitamin D and H. pylori infection among apparently healthy infants and toddlers. In this large cross-sectional study, the examination data of children were collected from January 2013 to September 2017 in the Center for Children's Health Care. Among these children, 6,896 infants and toddlers were screened for our study. Helicobacter pylori infection and vitamin D status were the main indicators, and micronutrients (zinc, iron, copper, magnesium), and growth parameters (height, weight, and weight for age Z score [WAZ], height for age Z score [HAZ]) were also analyzed in this study. Among the 6,896 infants and toddlers, the detection rate of H. pylori seropositivity was 30.6%. The prevalence of vitamin D deficiency in H. pylori seropositive and seronegative groups was 20.7% and 12.1%, respectively (P < 0.001). The logistic regression analysis suggested children with H. pylori-positive antibody were 2.06 times more likely to be vitamin D deficient compared with children who had negative H. pylori antibody (odds ratio: 2.06; 95% CI: 1.77, 2.38) after controlling for confounding factors. These data suggested that there was a significant association between H. pylori seropositivity and vitamin D deficiency in children aged 6-36 months, which would make a contribution to the treatment and monitoring of vitamin D deficiency and H. pylori infection.

Type 1 neurofibromatosis in a three-year-old girl with B-lineage acute lymphocytic leukemia: A case report. / 1åž‹ç¥žç»çº¤ç»´ç˜¤ç— ä¼´æ€¥æ€§Bç³»æ·‹å·´ç»†èƒžç™½è¡€ç— 1例.

Neurofibromatosis 1 (NF1) is an autosomal dominant genetic disease first manifesting in childhood, which affects multiple organs, childhood development and neurocognitive status. These patients have a high predisposition to develop both benign and malignant tumors. On September 30, 2018, a rare case of NF1 with B-lineage acute lymphocytic leukemia (ALL) was treated in the Department of Pediatrics, Third Xiangya Hospital, Central South University. The child presented with café au lait macules (CALM) since the date of birth. And the diagnosis of B-lineage ALL was made by bone marrow cytomorphologic examination and immunological phenotype detection. ETV6/RUNX1 fusion gene was positive. Also, a de novo mutation of c.2773delT (p.Leu925Ter) was found in the exon of NF1 gene by gene sequencing, which was a nonsense mutation and led to the premature termination of peptide synthesis. Molecular genetic testing is recommended to confirm NF1, particularly in children with only pigmentary features of the diagnostic criteria. NF1-affected individuals should be referred to a specialist of NF1 clinical network for long-term follow-up and surveillance.

Analyzing the genes and pathways related to major depressive disorder via a systems biology approach.

INTRODUCTION: Major depressive disorder (MDD) is a mental disorder caused by the combination of genetic, environmental, and psychological factors. Over the years, a number of genes potentially associated with MDD have been identified. However, in many cases, the role of these genes and their relationship in the etiology and development of MDD remains unclear. Under such situation, a systems biology approach focusing on the function correlation and interaction of the candidate genes in the context of MDD will provide useful information on exploring the molecular mechanisms underlying the disease. METHODS: We collected genes potentially related to MDD by screening the human genetic studies deposited in PubMed (https://www.ncbi.nlm.nih.gov/pubmed). The main biological themes within the genes were explored by function and pathway enrichment analysis. Then, the interaction of genes was analyzed in the context of protein-protein interaction network and a MDD-specific network was built by Steiner minimal tree algorithm. RESULTS: We collected 255 candidate genes reported to be associated with MDD from available publications. Functional analysis revealed that biological processes and biochemical pathways related to neuronal development, endocrine, cell growth and/or survivals, and immunology were enriched in these genes. The pathways could be largely grouped into three modules involved in biological procedures related to nervous system, the immune system, and the endocrine system, respectively. From the MDD-specific network, 35 novel genes potentially associated with the disease were identified. CONCLUSION: By means of network- and pathway-based methods, we explored the molecular mechanism underlying the pathogenesis of MDD at a systems biology level. Results from our work could provide valuable clues for understanding the molecular features of MDD.

Knowledge and behavior regarding pesticide use: a survey among caregivers of children aged 1-6 years from rural China.

Little is known about pesticide exposure risks for children in rural areas in China, many of whom have been left behind by migrant workers. To survey caregivers of children in rural China and assess their pesticide use and disposal methods, the measures were used to protect the children and their perceptions of the adverse effects of pesticides on children's health. Three or four villages in each of Xinhua, Gongan and Sansui Counties in China were selected by random cluster sampling. The main caregivers of children aged 1-6 years were surveyed in face-to-face interviews. The questionnaire used was adapted from the World Health Organization "Exposure to Pesticides: Standard Protocol" survey and similar studies. The study included 464 caregivers (mean age, 46.4 years), who were most commonly the children's grandparents (65.3%). Among the caregivers, 41.9% were educated to middle school level or higher, 45.4% had a household income < 297 USD, and 29.7% had received education/training about pesticide use/adverse health effects in children. The score for caregivers' knowledge of the adverse effects of pesticides on children's health was higher in those who had received education/training (5.1 ± 2.6 vs. 3.4 ± 2.5, P < 0.001). Factors associated with unsafe behaviors during pesticide use included grandparent as the caregiver (odds ratio [OR] 0.551; 95% confidence interval [95% CI] 0.368-0.824; P = 0.004), annual income < 297 USD (OR 0.580; 95% CI 0.395-0.853; P = 0.006), and insufficient health-related education/training (OR 0.436; 95% CI 0.286-0.665; P < 0.001). Improved education and training are needed to promote the safe use of pesticides by caregivers of children in rural China.

Chlorpyrifos activates cell pyroptosis and increases susceptibility on oxidative stress-induced toxicity by miR-181/SIRT1/PGC-1α/Nrf2 signaling pathway in human neuroblastoma SH-SY5Y cells: Implication for association between chlorpyrifos and Parkinson's disease.

BACKGROUND: The insecticide exposure has been linked to Parkinson's disease (PD). In the present study, we used a most widely used cell line in study of PD, the SH-SY5Y cells, to investigate mechanisms of chlorpyrifos (CPF) induced cell toxicity and the possible roles of cell pyroptosis and oxidative stress in SH-SY5Y cells, as well as role of miR-181/SIRT1/PGC-1α/Nrf2 signaling pathway in this process. METHODS: SH-SY5Y cells were treated with different concentrations of CPF. Cell viability was measured using CCK-8 assay. Cell pyroptosis was determined by immunofluorescence of caspase-1 and TUNEL assay. The miR-181 (has-miR-181-5p) level was determined by qRT-PCR. Expression of SIRT1, PGC-1α, Nrf2, and pyroptosis related proteins NLRP3, caspase-1, IL-1ß, and IL-18 was determined by both qRT-PCR and Western blotting. RESULTS: Cell viability was found to be decreased with the increased CPF concentrations. The pyroptosis related proteins, ROS levels, as well as level of caspase-1 and the TUNEL positive cells were all significantly up-regulated by CPF. Meanwhile, expression of miR-181 and pyroptosis proteins was also enhanced, while the SIRT1/PGC-1α/Nrf2 signaling was inhibited by CPF. Knockdown of Nrf2 significantly up-regulated the expression of pyroptosis related proteins, ROS level, caspase-1, and the TUNEL positive cells, while over-expression of Nrf2 resulted in opposite results. The expression of PGC-1α and Nrf2 was significantly down-regulated when SIRT1 was inhibited, while over-expressed SIRT1 led to increased PGC-1α and Nrf2 levels. Besides, miR-181 promoted the CPF induced activation of pyroptosis and oxidative stress, as well as down-regulated SIRT1/PGC-1α/Nrf2 signaling, while inhibition of miR-181 led to opposite results. CONCLUSIONS: Chlorpyrifos could inhibit cell proliferation, activate cell pyroptosis and increase susceptibility on oxidative stress-induced toxicity by elevating miR-181 through down-regulation of the SIRT1/PGC-1α/Nrf2 pathway in human neuroblastoma SH-SY5Y cells. This study might give deeper insights for mechanisms of CPF induced toxicity and might give some novel research targets for PD treatment.

Functional divergence analysis of vertebrate neuronal nicotinic acetylcholine receptor subunits.

Nicotinic acetylcholine receptors (nAChRs) are pentamers formed by subunits from a large multigene family and are highly variable in kinetic, electrophysiological and pharmacological properties. Due to the essential roles of nAChRs in many physiological procedures and diversity in function, identifying the function-related sites specific to each subunit is not only necessary to understand the properties of the receptors but also useful to design potential therapeutic compounds that target these macromolecules for treating a series of central neuronal disorders. By conducting a detailed function divergence analysis on nine neuronal nAChR subunits from representative vertebrate species, we revealed the existence of significant functional variation between most subunit pairs. Specifically, 44 unique residues were identified for the α7 subunit, while another 22 residues that were likely responsible for the specific features of other subunits were detected. By mapping these sites onto the 3 D structure of the human α7 subunit, a structure-function relationship profile was revealed. Our results suggested that the functional divergence related sites clustered in the ligand binding domain, the ß2-ß3 linker close to the N-terminal α-helix, the intracellular linkers between transmembrane domains, and the "transition zone" may have experienced altered evolutionary rates. The former two regions may be potential binding sites for the α7* subtype-specific allosteric modulators, while the latter region is likely to be subtype-specific allosteric modulations of the heteropentameric descendants such as the α4ß2* nAChRs. Communicated by Ramaswamy H. Sarma.

Evaluation of the effects of chlorpyrifos combined with lipopolysaccharide stress on neuroinflammation and spatial memory in neonatal rats.

Chlorpyrifos (CPF) may weaken the immune defenses of children, making them vulnerable to opportunistic bacterial infection. CPF combined with bacterial infection is a potential problem for children during their childhood development. However, there is a lack of studies on the joint effects of these two factors on children. Here, we assessed the effects of CPF combined with lipopolysaccharide (LPS) on the inflammation and development of the nervous system. In this study, the cell toxicity of CPF plus LPS in cultured astrocytes, and the pathogenic effects of CPF plus LPS in neonatal rat models were observed. The hydrogen (H2)-inhalation was used for treatment to explore its therapeutic potential. We found that CPF plus LPS activated the astrocyte, which increased the expressions of HMGB1, TLR4, and p-NF-κB p65, while H2-inhalation reduced the expressions (p < 0.05). We also found that CPF plus LPS induced long-lasting spatial memory deficits throughout brain maturation. However, H2-inhalation improved rat performance in these behavioral experiments (p < 0.05). In conclusion, the sub-toxic concentration of CPF did not cause a significant damage in short term, but induced a severe long-term damage to the brain when combined with LPS. H2-inhalation reduced the neuronal damage and behavioral abnormalities caused by CPF and LPS exposure.

SGA as a Risk Factor for Cerebral Palsy in Moderate to Late Preterm Infants: a System Review and Meta-analysis.

Small for gestational age (SGA) is an established risk factor for cerebral palsy (CP) in term infants. However, there is conflicting data on the association between SGA and CP in moderate to late preterm infants. The aim of the article was to explore the relationship between SGA and CP in the moderate to late preterm infants and its strength by meta-analysis. We performed a system search in OVID (EMBASE and MEDLINE) and WANFANG from inception to May 2016. The study-specific risk estimates were pooled using the random-effect model. A total of seven studies were included in the meta-analysis, consisting of three cohort and four case-control studies. A statistically significant association was found between SGA and CP in moderate to late premature infants (OR: 2.34; 95% CI: 1.43-3.82). The association were higher in the several subgroups: 34-36 week gestational age (OR: 3.47; 95% CI: 1.29-9.31), SGA < 2SDs (OR: 3.48; 95% CI: 1.86-6.49), and malformation included in CP (OR: 3.00; 95% CI: 1.71-5.26). In moderate to late premature infants, SGA is a convenient and reliable predictor for CP. More studies are needed to explore the underlying mechanisms between SGA and CP association.

The effect of HMGB1 on sub-toxic chlorpyrifos exposure-induced neuroinflammation in amygdala of neonatal rats.

Chlorpyrifos (CPF), one of organophosphorus pesticides (OPs), is associated with developmental neurotoxicity. Inflammatory response is closely related with CPF-induced neurotoxicity. The present study aimed at exploring whether sub-toxic CPF exposure on neonatal rats results in neuroinflammation that mediated by HMGB1/TLR4/NF-κB signaling pathway in the amygdala. The neonatal rats were subcutaneously injected with 5mg/kg CPF for 4 consecutive days (postnatal day 11-14) with or without HMGB1 inhibitor, glycyrrhizin. We assessed the levels of pro-inflammatory cytokines at 12, 24, and 72 h after CPF exposure. The role of HMGB1 on neuroinflammation in sub-toxic exposure during brain development was studied. CPF-treated neonatal rats exhibited a significant increase in the expression of pro-inflammatory cytokines, such as IL-6, TNF-α and HMGB1, and a significant increase in the activation of NF-κB in the amygdala after CPF exposure. Inhibited HMGB1 reduced the release of IL-6 and TNF-α, and inhibited activation of NF-κB. Our findings indicate that CPF exposure on developmental brain might induce the activation of neuroinflammation mediated by HMGB1/TLR4/NF-κB pathway in the amygdala.