S-Nitrosylation of the histone deacetylase HDA19 stimulates its activity to enhance plant stress tolerance in Arabidopsis.

Arabidopsis histone deacetylase HDA19 is required for gene expression programs of a large spectrum of plant developmental and stress-responsive pathways. How this enzyme senses cellular environment to control its activity remains unclear. In this work, we show that HDA19 is post-translationally modified by S-nitrosylation at 4 Cysteine (Cys) residues. HDA19 S-nitrosylation depends on the cellular nitric oxide level, which is enhanced under oxidative stress. We find that HDA19 is required for cellular redox homeostasis and plant tolerance to oxidative stress, which in turn stimulates its nuclear enrichment, S-nitrosylation and epigenetic functions including binding to genomic targets, histone deacetylation and gene repression. The Cys137 of the protein is involved in basal and stress-induced S-nitrosylation, and is required for HDA19 functions in developmental, stress-responsive and epigenetic controls. Together, these results indicate that S-nitrosylation regulates HDA19 activity and is a mechanism of redox-sensing for chromatin regulation of plant tolerance to stress.

Ultrahigh-performance liquid chromatography Q-Exactive-Orbitrap mass spectrometry and molecular network analysis alongside network pharmacology to elucidate the active constituents and mechanism of action of Huahong tablet in treating pelvic inflammatory disease.

RATIONALE: Huahong tablet, a commonly used clinical Chinese patent medicine, shows good efficacy in treating pelvic inflammation and other gynaecological infectious diseases. However, the specific composition of Huahong tablets, which are complex herbal formulations, remains unclear. Therefore, this study aims to identify the active compounds and targets of Huahong tablets and investigate their mechanism of action in pelvic inflammatory diseases. METHODS: We utilised ultrahigh-performance liquid chromatography Q-Exactive-Orbitrap mass spectrometry and the relevant literature to identify the chemical components of Huahong tablets. The GNPS database was employed to further analyse and speculate on the components. Potential molecular targets of the active ingredients were predicted using the SwissTargetPrediction website. Protein-protein interaction analysis was conducted using the STRING database, with visualisation in Cytoscape 3.9.1. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the DAVID database. Additionally, a traditional Chinese medicine-ingredient-target-pathway network was constructed using Cytoscape 3.10.1. Molecular docking validation was carried out to investigate the interaction between core target and specific active ingredient. RESULTS: A total of 66 chemical components were identified, and 41 compounds were selected as potential active components based on the literature and the TCMSP database. Moreover, 38 core targets were identified as key targets in the treatment of pelvic inflammatory diseases with Huahong tablets. GO and KEGG enrichment analysis revealed 986 different biological functions and 167 signalling pathways. CONCLUSION: The active ingredients in Huahong tablets exert therapeutic effects on pelvic inflammatory diseases by acting on multiple targets and utilising different pathways. Molecular docking confirmed the high affinity between the specific active ingredients and disease targets.

[Analysis and prospect of correlation between relative molecular weight and efficacy of polysaccharides from medicinal plant resources].

Polysaccharides from medicinal plant resources are a kind of polymers extracted from medicinal plants. They are complex long chains formed by different monosaccharides connected via glucosidic bonds. These polysaccharides usually have straight chain and branched chain structures, and their relative molecular weight changes greatly. Modern studies have shown that the biological activi-ty of polysaccharides from medicinal plant resources is closely related to their relative molecular weight. This paper first reviewed the preparation and detection methods of polysaccharides from medicinal plant resources with different relative molecular weights. Then, the paper summarized and analyzed the general experience of the correlation between efficacy and relative molecular weight of polysaccharides from medicinal plant resources with different molecular weights. It was considered that polysaccharides with large relative molecular weights(>100 kDa) play a leading role in immune regulation. Polysaccharides with medium relative molecular weights(10-100 kDa) play a leading role in immune regulation and the protection of the liver. Polysaccharides with small relative molecular weights(<10 kDa) play a leading role in anti-oxidation, regulation of intestinal flora, regulation of blood glucose and lipids, anti-fatigue, and the protection of nerves. Therefore, precise development of polysaccharides from medicinal plant resources based on relative molecular weight is expected to improve their biological activity and application value.

Comprehensive genomic analyses of Vigna unguiculata provide insights into population differentiation and the genetic basis of key agricultural traits.

Vigna unguiculata is an important legume crop worldwide. The subsp. sesquipedalis and unguiculata are the two major types grown; the former is mainly grown in Asia to produce fresh pods, while the latter is mainly grown in Africa to produce seeds. Here, a chromosome-scale genome for subsp. sesquipedalis was generated by combining high-fidelity (HiFi) long-read sequencing with high-throughput chromosome conformation capture (Hi-C) technology. The genome size for all contigs and N50 were 594 and 18.5 Mb, respectively. The Hi-C interaction map helped cluster 91% of the contigs into 11 chromosomes. Genome comparisons between subsp. sesquipedalis and unguiculata revealed extensive genomic variations, and some variations resulted in gene loss. A germplasm panel with 315 accessions of V. unguiculata was resequenced, and a genomic variation map was constructed. Population structure and phylogenetic analyses suggested that subsp. sesquipedalis originated from subsp. unguiculata. Highly differentiated genomic regions were also identified, and a number of genes functionally enriched in adaptations were located in these regions. Two traits, pod length (PL) and pod width (PW), were observed for this germplasm, and genome-wide association analysis of these traits was performed. The quantitative trait loci (QTLs) for these two traits were identified, and their candidate genes were uncovered. Interestingly, genomic regions of PL QTLs also showed strong signals of artificial selection. Taken together, the results of this study provide novel insights into the population differentiation and genetic basis of key agricultural traits in V. unguiculata.

Evaluation of the effect of physical therapy on pain and dysfunction of knee osteoarthritis based on fNIRS: a randomized controlled trial protocol.

BACKGROUND: Knee osteoarthritis (KOA) is a chronic musculoskeletal disease that can cause joint pain and dysfunction, affecting the quality of life of patients. Nonsurgical treatment is the conventional treatment of KOA, among which physical therapy is widely used because of its simplicity, convenience and effectiveness. The functional biomarker will add to the clinical fidelity and diagnostic accuracy. Therefore, our study chose a more objective evaluation indicator, functional near-infrared spectroscopy (fNIRS), to identify between healthy people and KOA patients, and to detect the pain change before and after treatment of KOA patients. METHODS: The study will be conducted in the Rehabilitation Medical Center of West China Hospital of Sichuan University and divided into 2 stages. In the first stage, we will compare and determine the differences in baseline data between healthy volunteers and KOA patients. In the second stage, 72 KOA patients will be randomly divided into two groups: the drug therapy group (DT) and the combination therapy group (CT) for 10 treatments. Outcome measures will be measured at baseline and on the 5th and 10th days after the intervention, including the numerical rating scale (NRS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), pain catastrophizing scale (PCS), the association of pain severity with task-state functional connectivity fNIRS and association of pain severity with task-activated fNIRS. DISCUSSION: By analyzing the fNIRS data of healthy volunteers and KOA patients, our study will be determined whether fNIRS can be used as a new indicator to reflect the severity of pain in KOA patients. Subsequently, the same fNIRS data for KOA patients before and after the intervention will be collected to provide an accurate evaluation criterion for the effect of physical therapy on KOA. TRIAL REGISTRATION: The study was registered on the Chinese Registry website (registered in ChiCTR.org with the identifiers ChiCTR2200064175 and 29/09/2022).

Factors associated with subgroups of fatigue in maintenance hemodialysis patients: a cross-sectional study.

OBJECTIVE: This study aimed to investigate affected factors for subgroups of fatigue and the degree of fatigue in maintenance hemodialysis (MHD) patients. METHODS: This study included 120 MHD patients. Questionnaires, pre- and post-dialysis clinical data, bioimpedance spectroscopy, and ultrasound assessment were involved. RESULTS: The prevalence of fatigue in participants was 83%, including 54% of patients with fatigue worsened by dialysis, 13% with fatigue lessened by dialysis, and 16% with undifferentiated fatigue. Based on multi-nominal logistic regression analysis, age was associated with worsened fatigue by dialysis (odds ratio (OR) = 1.06, 95% confidence interval (CI) 1.01-1.11, p = 0.019), lower post-dialysis phosphorus was associated with lessened fatigue by dialysis (OR = 0.03, 95% CI 0.001-0.981, p = 0.049), and there was an increasing trend of patients experiencing undifferentiated fatigue as the extracellular water / intracellular water (E/I) level increased (p for trend = 0.020). Based on multi-ordinal logistic regression analysis, age was also a significant predictor for more severe fatigue (OR = 1.042, 95% CI 1.008-1.059, p = 0.015). CONCLUSIONS: Different subgroups of fatigue in MHD patients have different affecting factors. Older patients were prone to worsened fatigue by dialysis, patients with lower post-dialysis phosphorus were prone to lessened fatigue by dialysis, and patients with higher E/I levels were prone to undifferentiated fatigue. Meanwhile, older patients are prone to suffer from more severe fatigue. However, more in-depth studies are needed to clarify the pathogenesis of fatigue in MHD patients.

Dual-YOLO Architecture from Infrared and Visible Images for Object Detection.

With the development of infrared detection technology and the improvement of military remote sensing needs, infrared object detection networks with low false alarms and high detection accuracy have been a research focus. However, due to the lack of texture information, the false detection rate of infrared object detection is high, resulting in reduced object detection accuracy. To solve these problems, we propose an infrared object detection network named Dual-YOLO, which integrates visible image features. To ensure the speed of model detection, we choose the You Only Look Once v7 (YOLOv7) as the basic framework and design the infrared and visible images dual feature extraction channels. In addition, we develop attention fusion and fusion shuffle modules to reduce the detection error caused by redundant fusion feature information. Moreover, we introduce the Inception and SE modules to enhance the complementary characteristics of infrared and visible images. Furthermore, we design the fusion loss function to make the network converge fast during training. The experimental results show that the proposed Dual-YOLO network reaches 71.8% mean Average Precision (mAP) in the DroneVehicle remote sensing dataset and 73.2% mAP in the KAIST pedestrian dataset. The detection accuracy reaches 84.5% in the FLIR dataset. The proposed architecture is expected to be applied in the fields of military reconnaissance, unmanned driving, and public safety.

Nerve Injury-Induced γH2AX Reduction in Primary Sensory Neurons Is Involved in Neuropathic Pain Processing.

Phosphorylation of the serine 139 of the histone variant H2AX (γH2AX) is a DNA damage marker that regulates DNA damage response and various diseases. However, whether γH2AX is involved in neuropathic pain is still unclear. We found the expression of γH2AX and H2AX decreased in mice dorsal root ganglion (DRG) after spared nerve injury (SNI). Ataxia telangiectasia mutated (ATM), which promotes γH2AX, was also down-regulated in DRG after peripheral nerve injury. ATM inhibitor KU55933 decreased the level of γH2AX in ND7/23 cells. The intrathecal injection of KU55933 down-regulated DRG γH2AX expression and significantly induced mechanical allodynia and thermal hyperalgesia in a dose-dependent manner. The inhibition of ATM by siRNA could also decrease the pain threshold. The inhibition of dephosphorylation of γH2AX by protein phosphatase 2A (PP2A) siRNA partially suppressed the down-regulation of γH2AX after SNI and relieved pain behavior. Further exploration of the mechanism revealed that inhibiting ATM by KU55933 up-regulated extracellular-signal regulated kinase (ERK) phosphorylation and down-regulated potassium ion channel genes, such as potassium voltage-gated channel subfamily Q member 2 (Kcnq2) and potassium voltage-gated channel subfamily D member 2 (Kcnd2) in vivo, and KU559333 enhanced sensory neuron excitability in vitro. These preliminary findings imply that the down-regulation of γH2AX may contribute to neuropathic pain.

Ultralow loss hollow-core negative curvature fibers with nested elliptical antiresonance tubes.

Hollow-core negative curvature fibers can confine light within air core and have small nonlinearity and dispersion and high damage threshold, thereby attracting a great deal of interest in the field of hollow core fibers. However, reducing the loss of hollow-core negative curvature fibers is a serious problem. On this basis, three new types of fibers with different nested tube structures are proposed in the near-infrared spectral regions and compared in detail with a previously proposed hollow-core negative curvature fiber. We used finite-element method for numerical simulation studies of their transmission loss, bending loss, and single-mode performance, and then the transmission performance of various structural fibers is compared. We found that the nested elliptical antiresonant fiber 1 has better transmission performance than that of the three other types of fibers in the spectral range of 0.72-1.6 µm. Results show that the confinement loss of the LP01 mode is as low as 6.45×10-6 dB/km at λ = 1.06 µm. To the best of our knowledge, the record low level of confinement loss of hollow-core antiresonant fibers with nested tube structures was created. In addition, the nested elliptical antiresonant fiber 1 has better bending resistance, and its bending loss was below 2.99×10-2 dB/km at 5 cm bending radius.

Varifocal liquid lens driven by a conical dielectric elastomer actuator.

A varifocal lens is an important part of optical systems with applications in biomedicine, photography, smartphones, and virtual reality. In this paper, we propose and demonstrate a varifocal liquid lens driven by a conical dielectric elastomer actuator. When the conical dielectric elastomer is subjected to an actuation voltage, the conical dielectric elastomer works as an out-plane actuator and makes the surface curvature of the liquid droplet increase; then the focal length of the proposed varifocal liquid lens changes. The overall dimensions of the proposed varifocal liquid lens are 9.4 mm in diameter and 12.5 mm in height. The focal length tuning range is 15.07mm∼9.50mm when the actuation voltage increases from 0 kV to 5.0 kV. The focal power variation of the proposed varifocal liquid lens is 35.5 D. The rise and fall times of the proposed varifocal liquid lens are 215 ms and 293 ms, respectively. The ability of the proposed liquid lens to focus on objects at different distances without any moving parts is demonstrated. The compact varifocal liquid lens driven by the conical dielectric elastomer actuator in the current study has the potential to be used in various compact imaging systems in the future.

A Novel Transformer-Based Attention Network for Image Dehazing.

Image dehazing is challenging due to the problem of ill-posed parameter estimation. Numerous prior-based and learning-based methods have achieved great success. However, most learning-based methods use the changes and connections between scale and depth in convolutional neural networks for feature extraction. Although the performance is greatly improved compared with the prior-based methods, the performance in extracting detailed information is inferior. In this paper, we proposed an image dehazing model built with a convolutional neural network and Transformer, called Transformer for image dehazing (TID). First, we propose a Transformer-based channel attention module (TCAM), using a spatial attention module as its supplement. These two modules form an attention module that enhances channel and spatial features. Second, we use a multiscale parallel residual network as the backbone, which can extract feature information of different scales to achieve feature fusion. We experimented on the RESIDE dataset, and then conducted extensive comparisons and ablation studies with state-of-the-art methods. Experimental results show that our proposed method effectively improves the quality of the restored image, and it is also better than the existing attention modules in performance.

Tryptophan-kynurenine metabolism: a link between the gut and brain for depression in inflammatory bowel disease.

Inflammatory bowel disease (IBD), which mainly includes ulcerative colitis (UC) and Crohn's disease (CD), is a group of chronic bowel diseases that are characterized by abdominal pain, diarrhea, and bloody stools. IBD is strongly associated with depression, and its patients have a higher incidence of depression than the general population. Depression also adversely affects the quality of life and disease prognosis of patients with IBD. The tryptophan-kynurenine metabolic pathway degrades more than 90% of tryptophan (TRP) throughout the body, with indoleamine 2,3-dioxygenase (IDO), the key metabolic enzyme, being activated in the inflammatory environment. A series of metabolites of the pathway are neurologically active, among which kynerunic acid (KYNA) and quinolinic acid (QUIN) are molecules of great interest in recent studies on the mechanisms of inflammation-induced depression. In this review, the relationship between depression in IBD and the tryptophan-kynurenine metabolic pathway is overviewed in the light of recent publications.

Tunable lens using dielectric elastomer sandwiched by transparent conductive liquid.

We propose and demonstrate a compact tunable lens with high transmittance using a dielectric elastomer sandwiched by transparent conductive liquid. The transparent conductive liquid not only serves as the refractive material of the tunable lens but also works as the compliant electrode of the dielectric elastomer. The overall dimensions of the proposed tunable lens are 16 mm in diameter and 10 mm in height, and the optical transmittance is as high as 92.2% at 380-760 nm. The focal power variation of the tunable lens is -23.71D at an actuation voltage of 3.0 kV. The rise and fall times are 60 ms and 185 ms, respectively. The fabrication process of the tunable lens is free of the deposition of opaque compliant electrodes. Such a tunable lens promises a potential solution in various compact imaging systems.

Enantioselective decarboxylative Mannich reaction of ß-keto acids with C-alkynyl N-Boc N,O-acetals: access to chiral ß-keto propargylamines.

The chiral keto-substituted propargylamines are an essential class of multifunctional compounds in the field of organic and pharmaceutical synthesis and have attracted considerable attention, but the related synthetic approaches remain limited. Therefore, a concise and efficient method for the enantioselective synthesis of ß-keto propargylamines via chiral phosphoric acid-catalyzed asymmetric Mannich reaction between ß-keto acids and C-alkynyl N-Boc N,O-acetals as easily available C-alkynyl imine precursors has been demonstrated here, affording a broad scope of ß-keto N-Boc-propargylamines in high yields (up to 97%) with generally high enantioselectivities (up to 97 : 3 er).

Development and multicenter validation of a nomogram for preoperative prediction of lymph node positivity in pancreatic cancer (NeoPangram).

BACKGROUND: Neoadjuvant therapy is associated with nodal downstaging and improved oncological outcomes in patients with lymph node (LN)-positive pancreatic cancer. This study aimed to develop and validate a nomogram to preoperatively predict LN-positive disease. METHODS: A total of 558 patients with resected pancreatic cancer were randomly and equally divided into development and internal validation cohorts. Multivariate logistic regression analysis was used to construct the nomogram. Model performance was evaluated by discrimination, calibration, and clinical usefulness. An independent multicenter cohort consisting of 250 patients was used for external validation. RESULTS: A four-marker signature was built consisting of carbohydrate antigen 19-9 (CA19-9), CA125, CA50, and CA242. A nomogram was constructed to predict LN metastasis using three predictors identified by multivariate analysis: risk score of the four-marker signature, computed tomography-reported LN status, and clinical tumor stage. The prediction model exhibited good discrimination ability, with C-indexes of 0.806, 0.742 and 0.763 for the development, internal validation, and external validation cohorts, respectively. The model also showed good calibration and clinical usefulness. A cut-off value (0.72) for the probability of LN metastasis was determined to separate low-risk and high-risk patients. Kaplan-Meier survival analysis revealed a good agreement of the survival curves between the nomogram-predicted status and the true LN status. CONCLUSIONS: This nomogram enables the identification of pancreatic cancer patients at high risk for LN positivity who may have more advanced disease and thus could potentially benefit from neoadjuvant therapy.

Penisarins A and B, Sesquiterpene Coumarins Isolated from an Endophytic Penicillium sp.

Penisarins A (1) and B (2), sesquiterpene coumarins with an unusual tricyclic sesquiterpene system, were isolated from endophytic Penicillium sp. KMU18029. Their structures were elucidated on the basis of spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compound 2 showed significant cytotoxicities against two human cancer cell lines, HL-60 and SMMC-7721, with IC50 values of 3.6 ± 0.2 and 3.7 ± 0.2 µM, respectively.

Demethylation of G-Protein-Coupled Receptor 151 Promoter Facilitates the Binding of Krüppel-Like Factor 5 and Enhances Neuropathic Pain after Nerve Injury in Mice.

G-protein-coupled receptors are considered to be cell-surface sensors of extracellular signals, thereby having a crucial role in signal transduction and being the most fruitful targets for drug discovery. G-protein-coupled receptor 151 (GPR151) was reported to be expressed specifically in the habenular area. Here we report the expression and the epigenetic regulation of GRP151 in the spinal cord after spinal nerve ligation (SNL) and the contribution of GPR151 to neuropathic pain in male mice. SNL dramatically increased GPR151 expression in spinal neurons. GPR151 mutation or spinal inhibition by shRNA alleviated SNL-induced mechanical allodynia and heat hyperalgesia. Interestingly, the CpG island in the GPR151 gene promoter region was demethylated, the expression of DNA methyltransferase 3b (DNMT3b) was decreased, and the binding of DNMT3b with GPR151 promoter was reduced after SNL. Overexpression of DNMT3b in the spinal cord decreased GPR151 expression and attenuated SNL-induced neuropathic pain. Furthermore, Krüppel-like factor 5 (KLF5), a transcriptional factor of the KLF family, was upregulated in spinal neurons, and the binding affinity of KLF5 with GPR151 promoter was increased after SNL. Inhibition of KLF5 reduced GPR151 expression and attenuated SNL-induced pain hypersensitivity. Further mRNA microarray analysis revealed that mutation of GPR151 reduced the expression of a variety of pain-related genes in response to SNL, especially mitogen-activated protein kinase (MAPK) signaling pathway-associated genes. This study reveals that GPR151, increased by DNA demethylation and the enhanced interaction with KLF5, contributes to the maintenance of neuropathic pain via increasing MAPK pathway-related gene expression.SIGNIFICANCE STATEMENT G-protein-coupled receptors (GPCRs) are targets of various clinically approved drugs. Here we report that SNL increased GPR151 expression in the spinal cord, and mutation or inhibition of GPR151 alleviated SNL-induced neuropathic pain. In addition, SNL downregulated the expression of DNMT3b, which caused demethylation of GPR151 gene promoter, facilitated the binding of transcriptional factor KLF5 with the GPR151 promoter, and further increased GPR151 expression in spinal neurons. The increased GPR151 may contribute to the pathogenesis of neuropathic pain via activating MAPK signaling and increasing pain-related gene expression. Our study reveals an epigenetic mechanism underlying GPR151 expression and suggests that targeting GPR151 may offer a new strategy for the treatment of neuropathic pain.

Establishment and comparison of Actinobacillus pleuropneumoniae experimental infection model in mice and piglets.

Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia, a disease responsible for substantial losses in the worldwide pig industry. In this study, outbred Kunming (KM) and Institute of Cancer Research (ICR) mice were evaluated as alternative mice models for APP research. After intranasal infection of serotype 5 reference strain L20, there was less lung damage and a lower clinical sign score in ICR compared to KM mice. However, ICR mice showed more obvious changes in body weight loss, the amount of immune cells (such as neutrophils and lymphocytes) and cytokines (such as IL-6, IL-1ß and TNF-α) in blood and bronchoalveolar lavage fluid (BALF). The immunological changes observed in ICR mice closely mimicked those found in piglets infected with L20. While both ICR and KM mice are susceptible to APP and induce pathological lesions, we suggest that ICR and KM mice are more suitable for immunological and pathogenesis studies, respectively. The research lays the theoretical basis for determine that mice could replace pigs as the APP infection model and it is of significance for the study of APP infection in the laboratory.

Effects of Acupuncture Treatment on Lower Limb Spasticity in Patients Following Hemorrhagic Stroke: A Pilot Study.

BACKGROUND AND PURPOSE: Lower limb spasticity is often a significant problem in stoke rehabilitation. The purpose of this study was to investigate the effects of acupuncture treatment on lower limb spasticity in patients following hemorrhagic stroke. METHODS: Fifty-nine patients following hemorrhagic stroke were randomized to receive acupuncture treatment combined with conventional treatment (treatment group [TG]) or conventional treatment only (control group [CG]). Acupuncture treatments were given in 24 sessions over 4 weeks. Blinded evaluation was based on Modified Ashworth Scale (MAS), short intracortical inhibition (SICI), and Hmax/Mmax ratio as the primary outcomes. In addition, Fugl-Meyer Assessment (FMA), Barthel Index (BI), motor evoked potential (MEP) and surface integrated electromyogram (IEMG) were employed as the secondary outcomes. All the evaluations were performed at 14 and 28 days after the start of the treatment. RESULTS: Compared with the CG, the TG showed a significantly greater over-time decrease in MAS for knee (p = 0.022) and ankle (p = 0.017), SICI (p = 0.000) and Hmax/Mmax ratio (p = 0.000). In all patients of TG, we found a greater improvement in lower-limb FMA and MEP but not in BI. IEMG show that TG obtained a greater reduction in spastic agonist muscles and a greater enhancement in spastic antagonist muscles. A significant correlation between a greater decrease in ankle MAS and a greater increase in SICI for spastic muscles was found (r = 0.390, p = 0.002). CONCLUSIONS: Acupuncture could improve the lower limb spasticity and motor function, thus providing a safe and economical approach for treating stroke patients. The potential mechanism underpinning the greater improvement may be attributed to a reshape of corticospinal plasticity induced by acupuncture.

Promoted Interaction of C/EBPα with Demethylated Cxcr3 Gene Promoter Contributes to Neuropathic Pain in Mice.

DNA methylation has been implicated in the pathogenesis of chronic pain. However, the specific genes regulated by DNA methylation under neuropathic pain condition remain largely unknown. Here we investigated how chemokine receptor CXCR3 is regulated by DNA methylation and how it contributes to neuropathic pain induced by spinal nerve ligation (SNL) in mice. SNL increased Cxcr3 mRNA and protein expression in the neurons of the spinal cord. Meanwhile, the CpG (5'-cytosine-phosphate-guanine-3') island in the Cxcr3 gene promoter region was demethylated, and the expression of DNA methyltransferase 3b (DNMT3b) was decreased. SNL also increased the binding of CCAAT (cytidine-cytidine-adenosine-adenosine-thymidine)/enhancer binding protein α (C/EBPα) with Cxcr3 promoter and decreased the binding of DNMT3b with Cxcr3 promoter in the spinal cord. C/EBPα expression was increased in spinal neurons after SNL, and inhibition of C/EBPα by intrathecal small interfering RNA attenuated SNL-induced pain hypersensitivity and reduced Cxcr3 expression. Furthermore, SNL-induced mechanical allodynia and heat hyperalgesia were markedly reduced in Cxcr3-/- mice. Spinal inhibition of Cxcr3 by shRNA or CXCR3 antagonist also attenuated established neuropathic pain. Moreover, CXCL10, the ligand of CXCR3, was increased in spinal neurons and astrocytes after SNL. Superfusing spinal cord slices with CXCL10 enhanced spontaneous EPSCs and potentiated NMDA-induced and AMPA-induced currents of lamina II neurons. Finally, intrathecal injection of CXCL10 induced CXCR3-dependent pain hypersensitivity in naive mice. Collectively, our results demonstrated that CXCR3, increased by DNA demethylation and the enhanced interaction with C/EBPα, can be activated by CXCL10 to facilitate excitatory synaptic transmission and contribute to the maintenance of neuropathic pain. SIGNIFICANCE STATEMENT: Peripheral nerve injury induces changes of gene expression in the spinal cord that may contribute to the pathogenesis of neuropathic pain. CXCR3 is a chemokine receptor. Whether it is involved in neuropathic pain and how it is regulated after nerve injury remain largely unknown. Our study demonstrates that spinal nerve ligation downregulates the expression of DNMT3b, which may cause demethylation of Cxcr3 gene promoter and facilitate the binding of CCAAT/enhancer binding protein α with Cxcr3 promoter and further increase CXCR3 expression in spinal neurons. The upregulated CXCR3 may contribute to neuropathic pain by facilitating central sensitization. Our study reveals an epigenetic mechanism underlying CXCR3 expression and also suggests that targeting the expression or activation of CXCR3 signaling may offer new therapeutics for neuropathic pain.