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Cardiovascular safety assessment is vital for drug development, yet human cardiovascular cell models are lacking. In vitro mass-generated human pluripotent stem cell (hPSC)-derived cardiovascular cells are a suitable cell model for preclinical cardiovascular safety evaluations. In this study, we established a preclinical toxicology model using same-origin hPSC-differentiated cardiomyocytes (hPSC-CMs) and endothelial cells (hPSC-ECs). For validation of this cell model, alirocumab, a human antibody against proprotein convertase subtilisin kexin type 9 (PCSK9), was selected as an emerging safe lipid-lowering drug; atorvastatin, a common statin (the most effective type of lipid-lowering drug), was used as a drug with reported side effects at high concentrations, while doxorubicin was chosen as a positive cardiotoxic drug. The cytotoxicity of these drugs was assessed using CCK8, ATP, and lactate dehydrogenase release assays at 24, 48, and 72 h. The influences of these drugs on cardiomyocyte electrophysiology were detected using the patch-clamp technique, while their effects on endothelial function were determined by tube formation and Dil-acetylated low-density lipoprotein (Dil-Ac-LDL) uptake assays. We showed that alirocumab did not affect the cell viability or cardiomyocyte electrophysiology in agreement with the clinical results. Atorvastatin (5–50 μM) dose-dependently decreased cardiovascular cell viability over time, and at a high concentration (50 μM, ~100 times the normal peak serum concentration in clinic), it affected the action potentials of hPSC-CMs and damaged tube formation and Dil-Ac-LDL uptake of hPSC-ECs. The results demonstrate that the established same-origin hPSC-derived cardiovascular cell model can be used to evaluate lipid-lowering drug safety in cardiovascular cells and allow highly accurate preclinical assessment of potential drugs.

Aims Irritable bowel syndrome (IBS) is a common functional gastrointestinal disease characterized by abdominal pain. Our recent study has shown that the acid‐sensitive ion channel 1 (ASIC1) in dorsal root ganglion (DRG) is involved in stomachache of adult offspring rats subjected with prenatal maternal stress (PMS). MiR‐485 is predicted to target the expression of ASIC1. The aim of the present study was designed to determine whether miR‐485/ASIC1 signaling participates in enterodynia in the spinal dorsal horn of adult offspring rats with PMS. Methods Enterodynia was measured by colorectal distension (CRD). Western blotting, qPCR, and in situ hybridization were performed to detect the expression of ASICs and related miRNAs. Spinal synaptic transmission was also recorded by patch clamping. Results PMS offspring rats showed that spinal ASIC1 protein expression and synaptic transmission were significantly enhanced. Administration of ASICs antagonist amiloride suppressed the synaptic transmission and enterodynia. Besides, PMS induced a significant reduction in the expression of miR‐485. Upregulating the expression markedly attenuated enterodynia, reversed the increase in ASIC1 protein and synaptic transmission. Furthermore, ASIC1 and miR‐485 were co‐expressed in NeuN‐positive spinal dorsal horn neurons. Conclusions Overall, these data suggested that miR‐485 participated in enterodynia in PMS offspring, which is likely mediated by the enhanced ASIC1 activities., The present study has shown that miR‐485 negatively regulates ASIC1 expression and synaptic transmission in the spinal dorsal horn, thus eventually contributing to enterodynia of PMS offspring. It tips us to prevent the adverse effects on offspring induced by environmental stressors during pregnancy.

Background Inflammatory pain is the most common type of pain treated clinically. However, the currently available treatments for inflammatory pain have limited effects and can cause severe side effects. The aim of this study is to describe the effect of miRNA-485-5p on osteoarthritis-related inflammatory pain. Methods Paw withdrawal threshold (PWT) of rats was measured by von Frey filaments. The expressions of miRNA-485-5p and acid-sensing ion channel 1 (ASIC1) in the dorsal root ganglion (DRG) were measured with real-time quantitative PCR and Western blotting analysis. Fluorescent in situ hybridization and fluorescent immunohistochemistry were employed to detect expression of miRNA-485-5p, acid-sensing ion channelASIC1 and co-location of miRNA-485-5p with ASIC1. Results The PWT of rats was significantly reduced after complete Freund’s adjuvant (CFA) injection. The miRNA-485-5p expression level clearly decreased while the ASIC1 expression level was upregulated in the L4-6 dorsal root ganglion (DRG) of CFA rats. MiRNA-485-5p and ASIC1 were co-expressed in the same DRG cells of CFA rats. Amiloride, an inhibitor of ASIC1, clearly increased the PWT of CFA rats. Further, miRNA-485-5p agomir reversed the upregulation of ASICI1 and alleviated CFA-induced mechanical hypersensitivity of CFA rats. Conclusion These results suggest that reduced expression of miRNA-485-5p contributes to inflammatory pain through upregulating ASIC1 expression, implying a promising strategy for pain therapy.

Chronic visceral pain is one of the primary symptoms of patients with irritable bowel syndrome (IBS), which affects up to 15% of the population world-wide. The detailed mechanisms of visceral pain remain largely unclear. Our previous studies have shown that neonatal maternal deprivation (NMD) followed by adult multiple stress (AMS) advances the occurrence of visceral pain, likely due to enhanced norepinephrine (NE)-β2 adrenergic signaling. This study was designed to explore the roles of P2X3 receptors (P2X3Rs) in the chronic visceral pain induced by combined stress. Here, we showed that P2X3Rs were co-expressed in β2 adrenergic receptor (β2-AR)-positive dorsal root ganglion neurons and that NE significantly enhanced ATP-induced Ca2+ signals. NMD and AMS not only significantly increased the protein expression of P2X3Rs, but also greatly enhanced the ATP-evoked current density, number of action potentials, and intracellular Ca2+ concentration of colon-related DRG neurons. Intrathecal injection of the P2X3R inhibitor A317491 greatly attenuated the visceral pain and the ATP-induced Ca2+ signals in NMD and AMS rats. Furthermore, the β2-AR antagonist butoxamine significantly reversed the expression of P2X3Rs, the ATP-induced current density, and the number of action potentials of DRG neurons. Overall, our data demonstrate that NMD followed by AMS leads to P2X3R activation, which is most likely mediated by upregulation of β2 adrenergic signaling in primary sensory neurons, thus contributing to visceral hypersensitivity.

Aims Painful diabetic neuropathy (PDN) is a refractory complication of diabetes. The study aimed to investigate the role of α‐lipoic acid (ALA) on the regulation of transient receptor potential vanilloid‐1 (TRPV1) in dorsal root ganglion (DRG) neurons of rats with diabetes. Methods Whole‐cell patch‐clamp recordings were employed to measure neuronal excitability in DiI‐labeled DRG neurons of control and streptozotocin (STZ)‐induced diabetic rats. Western blotting and immunofluorescence assays were used to determine the expression and location of NF‐κBp65 and TRPV1. Results STZ‐induced hindpaw pain hypersensitivity and neuronal excitability in L4‐6 DRG neurons were attenuated by intraperitoneal injection with ALA once a day lasted for one week. TRPV1 expression was enhanced in L4‐6 DRGs of diabetic rats compared with age‐matched control rats, which was also suppressed by ALA treatment. In addition, TRPV1 and p65 colocated in the same DRG neurons. The expression of p65 was upregulated in L4‐6 DRGs of diabetic rats. Inhibition of p65 signaling using recombinant lentiviral vectors designated as LV‐NF‐κBp65 siRNA remarkably suppressed TRPV1 expression. Finally, p65 expression was downregulated by ALA treatment. Conclusion Our findings demonstrated that ALA may alleviate neuropathic pain in diabetes by regulating TRPV1 expression via affecting NF‐κB.

This study aimed to assess the effects of cognitive behavioral therapy on the psychological and physiological health of rheumatoid arthritis patients. An extensive literature search was conducted, using the PubMed, Web of Science, Cochrane Library, Embase, CNKI Scholar, WanFang, and VIP databases, from inception to December2018. The quality of the studies was evaluated by 2 independent authors, according to the basic criteria provided by the Cochrane Handbook for evaluating randomized trials. Meta-analysis was performed with Review Manager 5.3. Six randomized controlled trials met the inclusion criteria of the current study. Using standard mean differences (SMD) and 95% confidence intervals (CI), our results showed that cognitive behavioral therapy could significantly reduce levels of anxiety (SMD = -0.30, 95% CI [-0.52, -0.09], P= 0.005) and depression (SMD = -0.48, 95% CI [-0.70, -0.27], P< 0.00001), and relieve fatigue symptoms (SMD = -0.35, 95% CI [-0.60, -0.10], P= 0.006) in rheumatoid arthritis patients.This is the first known assessment of the efficacy of cognitive behavioral therapy on rheumatoid arthritis patients using meta-analysis. Large-scale randomized controlled trials need to be implemented to further explore this issue.

Purinergic receptors have been reported to be involved in brain disorders. In this study, we explored their roles and mechanisms underlying the memory impairment in rats with type 2 diabetes mellitus (T2DM). T2DM rats exhibited a worse performance in the T-maze and Morris water maze (MWM) than controls. Microglia positive for P2X purinoceptor 4 (P2X4R) in the hippocampus were reduced and activated microglia were increased in T2DM rats. Long Amplicon PCR (LA-PCR) showed that DNA amplification of the p2x4r gene in the hippocampus was lower in T2DM rats. Minocycline significantly reduced the number of activated microglia and the mean distance traveled by T2DM rats in the MWM. Most importantly, P2X4R overexpression suppressed the activated microglia and rescued the memory impairment of T2DM rats. Overall, T2DM led to excessive activation of microglia in the hippocampus, partly through the DNA damage-mediated downregulation of P2X4Rs, thus contributing to memory impairment. Electronic supplementary material The online version of this article (10.1007/s12264-020-00478-7) contains supplementary material, which is available to authorized users.

Background: The aim of this study was to examine how body image, Disease Activity Score in 28 joints, the feeling of being anxious, depression, fatigue, quality of sleep, and pain influence the quality of life (QoL) in patients with rheumatoid arthritis (RA).Methods: A multicenter cross-sectional survey with convenience sampling was conducted from March 2019 and December 2019, 603 patients with RA from five hospitals were evaluated using the Body Image Disturbance Questionnaire, Disease Activity Score in 28 joints, Hospital Anxiety and Depression Scale, Fatigue Severity Scale, Pittsburgh Sleep Quality Index, Short Form 36 Health Survey, and Global Pain Scale. The relationship between quality of life and other variables was evaluated by using the structural equation model (SEM).Results: A total of 580 patients were recruited. SEM fitted the data very well with a root mean square error of approximation (RMSEA) of 0.072. Comparative fit index of 0.966, and Tucker-Lewis index of 0.936. The symptoms and the normalized factor load of six variables showed that the normalized factor load of pain was 0.99.Conclusions: The QoL model was used to fit an SEM to systematically verify and analyze the population disease data, biological factors, and the direct and indirect effects of the symptom group on the QoL, and the interactions between the symptoms. Therefore, the diagnosis, treatment and rehabilitation of RA is a long-term, dynamic, and complex practical process. Patients' personal symptoms, needs, and experiences also vary greatly. Comprehensive assessment of patients' symptoms, needs, and experiences, as well as the role of social support cannot be ignored, which can help to meet patients' nursing needs, improve their mood and pain-based symptom management, and ultimately improve patients' QoL.

Multiple sclerosis (MS) is a chronic and incurable autoimmune neurodegenerative disease of the central nervous system. Although the symptoms of MS can be managed by vitamin D3 treatment alone, this condition cannot be completely eradicated. Thus, there might be unknown factors capable of regulating the vitamin D receptor (VDR). Genome-wide analysis showed that miRNAs were associated with VDRs. We sought to determine the role and mechanism of action of miRNA-125a-5p and VDRs in a model of MS, mice with experimental autoimmune encephalomyelitis (EAE), which was induced by myelin oligodendrocyte glycoprotein 35–55 peptides. EAE mice showed decreased mean body weight but increased mean clinical scores compared with vehicle or control mice. And inflammatory infiltration was found in the lumbosacral spinal cord of EAE mice. In addition, VDR expression was significantly lower while the expression of miR-125a-5p was markedly higher in the spinal ventral horn of EAE mice than in vehicle or control mice. Importantly, activation of VDRs by paricalcitol or inhibition of miR-125a-5p by its antagomir markedly decreased the mean clinical scores in EAE mice. Interestingly, VDR and miR-125a-5p were co-localized in the same neurons of the ventral horn. More importantly, inhibition of miR-125a-5p remarkably blocked the decrease of VDRs in EAE mice. These results support a critical role for miR-125a-5p in modulating VDR activity in EAE and suggest potential novel therapeutic interventions.

Chronic visceral hypersensitivity is an important type of chronic pain with unknown etiology and pathophysiology. Recent studies have shown that epigenetic regulation plays an important role in the development of chronic pain conditions. However, the role of miRNA-325-5p in chronic visceral pain remains unknown. The present study was designed to determine the roles and mechanism of miRNA-325-5p in a rat model of chronic visceral pain. This model was induced by neonatal colonic inflammation (NCI). In adulthood, NCI led to a significant reduction in the expression of miRNA-325-5p in colon-related dorsal root ganglia (DRGs), starting to decrease at the age of 4 weeks and being maintained to 8 weeks. Intrathecal administration of miRNA-325-5p agomir significantly enhanced the colorectal distention (CRD) threshold in a time-dependent manner. NCI also markedly increased the expression of CCL2 (C-C motif chemokine ligand 2) in colon-related DRGs at the mRNA and protein levels relative to age-matched control rats. The expression of CXCL12, IL33, SFRS7, and LGI1 was not significantly altered in NCI rats. CCL2 was co-expressed in NeuN-positive DRG neurons but not in glutamine synthetase-positive glial cells. Furthermore, CCL2 was mainly expressed in isolectin B4-binding- and calcitonin gene-related peptide-positive DRG neurons but in few NF-200-positive cells. More importantly, CCL2 was expressed in miR-325-5p-positive DRG neurons. Intrathecal injection of miRNA-325-5p agomir remarkably reduced the upregulation of CCL2 in NCI rats. Administration of Bindarit, an inhibitor of CCL2, markedly raised the CRD threshold in NCI rats in a dose- and time-dependent manner. These data suggest that NCI suppresses miRNA-325-5p expression and enhances CCL2 expression, thus contributing to visceral hypersensitivity in adult rats. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12264-019-00372-x) contains supplementary material, which is available to authorized users.

The pathophysiology of visceral pain in patients with irritable bowel syndrome remains largely unknown. Our previous study showed that neonatal maternal deprivation (NMD) does not induce visceral hypersensitivity at the age of 6 weeks in rats. The aim of this study was to determine whether NMD followed by adult stress at the age of 6 weeks induces visceral pain in rats and to investigate the roles of adrenergic signaling in visceral pain. Here we showed that NMD rats exhibited visceral hypersensitivity 6 h and 24 h after the termination of adult multiple stressors (AMSs). The plasma level of norepinephrine was significantly increased in NMD rats after AMSs. Whole-cell patch-clamp recording showed that the excitability of dorsal root ganglion (DRG) neurons from NMD rats with AMSs was remarkably increased. The expression of β2 adrenergic receptors at the protein and mRNA levels was markedly higher in NMD rats with AMSs than in rats with NMD alone. Inhibition of β2 adrenergic receptors with propranolol or butoxamine enhanced the colorectal distention threshold and application of butoxamine also reversed the enhanced hypersensitivity of DRG neurons. Overall, our data demonstrate that AMS induces visceral hypersensitivity in NMD rats, in part due to enhanced NE-β2 adrenergic signaling in DRGs.

Irritable bowel syndrome (IBS) is one of the most common challenging diseases for clinical treatment. The aim of this study is to investigate whether transcranial direct current stimulation (tDCS) has analgesic effect on visceral hypersensitivity (VH) in an animal model of IBS as well as the underlying mechanism. As the activation of GluN2B in anterior cingulate cortex (ACC) takes part in VH, we examined whether and how GluN2B in ACC takes part in the effect of tDCS. Neonatal maternal deprivation (NMD), a valuable experimental model to study the IBS pathophysiology, was used to induce visceral hypersensitivity of rats. We quantified VH as colorectal distention threshold and performed patch-clamp recordings of ACC neurons. The expression of GluN2B were determined by RT-qPCR and Western blotting. The GluN2B antagonist Ro 25-6981 was microinjected into the rostral and caudal ACC. tDCS was performed for 7 consecutive days. It was found that NMD decreased expression of GluN2B, which could be obviously reversed by tDCS. Injection of Ro 25-6981 into rostral and caudal ACC of normal rats induced VH and also reversed the analgesic effect of tDCS. Our data sheds light on the nonpharmacological therapy for chronic VH in pathological states such as IBS. NEW & NOTEWORTHY Irritable bowel syndrome (IBS) is a gastrointestinal disease characterized by visceral hypersensitivity. This study showed a decrease of GluN2B expression and neural activity in ACC of IBS-model rats, which could be obviously reversed by tDCS. In addition, blockade of GluN2B in rostral and caudal ACC induced VH of normal rats. Furthermore, analgesic effect of tDCS on NMD rats was reversed by GluN2B antagonist.

Background Inflammatory pain is a severe clinical problem that affects the quality of life in patients. However, the currently available treatments for inflammatory pain have limited effect and even causes severe side effects. The aim of this study was to investigate the roles of miRNA-107 and glutamate transporter 1 (GLT-1) in the inflammatory pain of rats induced by complete Freund's adjuvant (CFA). Methods Paw withdrawal threshold (PWT) of rats was measured by von Frey Filaments. The expressions of miRNA-107 and GLT-1 in the lumbar spinal dorsal horn (L4-L6) were measured with real-time quantitative PCR and western blotting analysis. Fluorescent in situ hybridization and fluorescent-immunohistochemistry were employed to detect the expression of miRNA-107, GLT-1 and co-location of miRNA-107 with GLT-1. Results Injection of CFA significantly reduced PWT of rats. The miRNA-107 expression level was obviously up-regulated while the GLT-1 expression level was decreased in the spinal dorsal horn of CFA rats. miRNA-107 and GLT-1 were co-expressed in the same cells of the spinal dorsal horn in CFA rats. Ceftriaxone, a selective activator of GLT-1, obviously increased the PWT of CFA rats. Furthermore, antagomir of miRNA-107 reversed the down-regulation of GLT-1 and alleviated CFA-induced mechanical allodynia of CFA rats. Conclusions These results suggest that an increase of miR-107 contributes to inflammatory pain through downregulating GLT-1 expression, implying a promising strategy for pain therapy. Significance The currently available treatments for inflammatory pain has limited effect even causes severe side effects. MiRNAs may have important diagnostic and therapeutic potential in inflammatory pain. In present study, we show a potential spinal mechanism of allodynia in rat inflammatory pain model induced by CFA. Increased miR-107 contribute to inflammatory pain by targeting and downregulating GLT-1 expression, implying a promising strategy for inflammatory pain.

Aims: To determine whether acid-sensing ion channel 1 (ASIC1)–sodium-potassium-chloride cotransporter 1 (NKCC1) signaling pathway participates in chronic visceral pain of adult rats with neonatal maternal deprivation (NMD).Methods: Chronic visceral pain was detected by colorectal distension (CRD). Western blotting and Immunofluorescence were performed to detect the expression and location of ASIC1 and NKCC1. Whole-cell patch-clamp recordings were performed to record spinal synaptic transmission.Results: The excitatory synaptic transmission was enhanced and the inhibitory synaptic transmission was weakened in the spinal dorsal horn of NMD rats. ASIC1 and NKCC1 protein expression in the spinal dorsal horn was significantly up-regulated in NMD rats. Incubation of Amiloride reduced the amplitude of mEPSCs. Incubation of Bumetanide (BMT) increased the amplitude of mIPSCs. Intrathecal injection of ASIC1 or NKCC1 inhibitors reversed the threshold of CRD in NMD rats. Also, Amiloride treatment significantly reversed the expression of NKCC1 in the spinal dorsal horn of NMD rats.Conclusion: Our data suggest that the ASIC1-NKCC1 signaling pathway is involved in chronic visceral pain in NMD rats.

Cancer-induced pain (CIP) is a kind of chronic pain that occurs during cancer progression over time. However, the mechanisms are largely unknown, and clinical treatment remains challenging. LncRNAs have been reported to play critical roles in various biological processes, including chronic pain. The aim of our study was to investigate whether lncRNAs participate in the development of CIP by regulating the expression levels of some molecules related to pain modulation. The CIP model was established by injecting Walker 256 mammary gland tumor cells into the tibial canal of rats. In this study, we found that lncRNA-NONRATT021203.2 was increased in the CIP rats and that lncRNA-NONRATT021203.2-siRNA could relieve hyperalgesia in these rats. For elucidation of the underlying mechanism, we showed that lncRNA-NONRATT021203.2 could target C-X-C motif chemokine ligand 9 (CXCL9), which was increased in the CIP rats, and that CXCL9-siRNA could relieve hyperalgesia. At the same time, silencing lncRNA-NONRATT021203.2 expression decreased the mRNA and protein levels of CXCL9. Immunofluorescence analysis showed that CXCL9 was mainly expressed in the CGRP-positive and IB4-positive DRG neurons. Further research showed that lncRNA-NONRATT021203.2 and CXCL9 were colocalized in the DRG neurons. Our data suggested that lncRNA-NONRATT021203.2 participated in the CIP in rats and likely mediates the upregulation of CXCL9. The present study provided us with a new potential target for the clinical treatment of cancer-induced pain.

Stroke is the leading cause of disability and death in the world. Central post-stroke pain (CPSP), a central neuropathic pain syndrome occurring after cerebral stroke, is a serious problem. But on account of the lack of reliable animal models, the mechanisms underlying CPSP remains poorly understood. To better understand of the pathophysiological basis of CPSP, we developed and characterized a new rat model of CPSP. This model is based on a hemorrhagic stroke lesion with intra-thalamic autologous blood (ITAB) injection in the ventral posterolateral nucleus of the thalamus. Behavioral analysis demonstrated that the animals displayed a significant decrease in mechanical allodynia threshold. We found a significant increase in P2 × 4 receptor expression in microglia in thalamic peri-lesion tissues post-hemorrhage. The mechanical allodynia in rats with CPSP were reversed by blocking P2 × 4 receptors. A significant alleviation of mechanical allodynia was achieved following the administration of adrenergic antidepressants and antiepileptics. Meanwhile, we found a significant decrease in P2 × 4 receptor expression after treatment with these drugs. Taken together, our results suggest that targeting P2 × 4 receptor may be effective in the treatment of CPSP.

Yan Sun,1,* Pan-Pan Yang,1,* Zhen-Yuan Song,2 Yu Feng,1 Duan-Min Hu,1 Ji Hu,1 Guang-Yin Xu,3 Hong-Hong Zhang1,3 1Department of Endocrinology, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China; 2Department of Endocrinology, The East District of Suzhou Municipal Hospital, Suzhou, People’s Republic of China; 3Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases, Institute of Neuroscience, Soochow University, Suzhou, People’s Republic of China *These authors contributed equally to this work Aim: Patients with long-standing diabetes often demonstrate intestinal dysfunction, characterized as constipation or colonic hypersensitivity. Our previous studies have demonstrated the roles of voltage-gated sodium channels NaV1.7 and NaV1.8 in dorsal root ganglion (DRG) in colonic hypersensitivity of rats with diabetes. This study was designed to determine roles of antioxidant α-lipoic acid (ALA) on sodium channel activities and colonic hypersensitivity of rats with diabetes. Methods: Streptozotocin was used to induce diabetes in adult female rats. Colonic sensitivity was measured by behavioral responses to colorectal distention in rats. The excitability and sodium channel currents of colon projection DRG neurons labeled with DiI were measured by whole-cell patch-clamp recordings. The expressions of NaV1.7 and NaV1.8 of colon DRGs were measured by western blot analysis. Results: ALA treatment significantly increased distention threshold in responding to colorectal distension in diabetic rats compared with normal saline treatment. ALA treatment also hyperpolarized the resting membrane potentials, depolarized action potential threshold, increased rheobase, and decreased frequency of action potentials evoked by ramp current stimulation. Furthermore, ALA treatment also reduced neuronal sodium current densities of DRG neurons innervating the colon from rats with diabetes. In addition, ALA treatment significantly downregulated NaV1.7 and NaV1.8 expression in colon DRGs from rats with diabetes. Conclusion: Our results suggest that ALA plays an analgesic role, which was likely mediated by downregulation of NaV1.7 and NaV1.8 expressions and functions, thus providing experimental evidence for using ALA to treat colonic hypersensitivity in patients with diabetic visceral pain. Keywords: diabetes, colonic hypersensitivity, dorsal root ganglion, voltage-gated sodium channels, α-lipoic acid

Background/aims Gastric hypersensitivity contributes to abdominal pain in patients with functional dyspepsia. Recent studies showed that hormones induced by stress are correlated with visceral hypersensitivity. However, the precise mechanisms underlying gastric hypersensitivity remain largely unknown. The aim of the present study was designed to investigate the roles of corticosterone (CORT) on excitability of dorsal root ganglion (DRG) neurons innervating the stomach. Methods DRG neurons innervating the stomach were labeled by DiI injection into the stomach wall. Patch clamp recordings were employed to examine neural excitability and voltage-gated sodium channel currents. Electromyograph technique was used to determine the responses of neck muscles to gastric distension. Results Incubation of acutely isolated DRG neurons with CORT significantly depolarized action potential threshold and enhanced the number of action potentials induced by current stimulation of the neuron. Under voltage-clamp mode, incubation of CORT enhanced voltage-gated sodium current density of the recorded neurons. Pre-incubation of GF109203X, an inhibitor of protein kinase C, blocked the CORT-induced hyperexcitability and potentiation of sodium currents. However, pre-incubation of H-89, an inhibitor of protein kinase A, did not alter the sodium current density. More importantly, intraperitoneal injection of CORT produced gastric hypersensitivity of healthy rats, which was blocked by pre-administration of GF109203X but not H-89. Conclusions Our data strongly suggest that CORT rapidly enhanced neuronal excitability and sodium channel functions, which is most likely mediated by protein kinase C but not protein kinase A signaling pathway in DRG neurons innervating the stomach, thus underlying the gastric hypersensitivity induced by CORT injection.

// Yan Lv 1, * , Meng Si 2, * , Nannan Chen 3, * , Ya Li 3, * , Xingkai Ma 4 , Huijun Yang 4 , Ling Zhang 1 , Hongyan Zhu 1 , Guang-yin Xu 1, 3 , Ge-ping Wu 1, 4 and C. Cao 3 1 Center of Translational Medicine, The First People Hospital of Zhangjiagang City, Soochow University, Suzhou, China 2 Department of Neurology, The Second Affiliated Hospital of Soochow University, Suzhou, China 3 Institute of Neuroscience, Soochow University, Suzhou, China 4 Department of Otolaryngology, The First People Hospital of Zhangjiagang City, Soochow University, Suzhou, China * These authors have contributed equally to this work Correspondence to: Ge-ping Wu, email: gordon-wu@qq.com C. Cao, email: caocong@suda.edu.cn Guang-yin Xu, email: guangyinxu@suda.edu.cn Keywords: TBX2, nasopharyngeal cancer, invasion, proliferation, siRNA Received: December 06, 2016 Accepted: March 12, 2017 Published: April 13, 2017 ABSTRACT TBX2 is a member of the T box transcription factor family. Its expression and potential biological functions in nasopharyngeal cancer (NPC) cells are studied here. We showed that TBX2 mRNA and protein expression was significantly elevated in multiple human NPC tissues, as compared with that in adjacent normal tissues. Knockdown of TBX2 by targeted-siRNA significantly inhibited proliferation and invasion of NPC cells (CNE-1 and HONE-1 lines). Meanwhile, TBX2 knockdown also induced G1-phase cell cycle arrest. At the molecular level, we discovered that expressions of several tumor suppressor genes, including p21, p27, phosphatase with tensin homology (PTEN) and E-Cadherin , were increased dramatically after TBX2 knockdown in above NPC cells. Collectively, our results imply that TBX2 over-expression promotes NPC cell proliferation and invasion, possibly via silencing several key tumor suppressor genes.

BACKGROUND To investigate the effect that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has on surgical decision making relative to video-electroencephalography (VEEG) and positron emission tomography-computed tomography (PET-CT), and if the differences in these variables translates to differences in surgical outcomes. MATERIAL AND METHODS A total of 166 children with epilepsy undergoing preoperative DCE-MRI, VEEG, and PET-CT examinations, surgical resection of epileptic foci, and intraoperative electrocorticography (ECoG) monitoring were enrolled. All children were followed up for 12 months and grouped by Engles prognostic classification for epilepsy. Based on intraoperative ECoG as gold standard, the diagnostic values of DCE-MRI, VEEG, PET-CT, DCE-MRI combined with VEEG, DCE-MRI combined with PET-CT, and combined application of DCE-MRI, VEEG, and PET-CT in preoperative localization for epileptic foci were evaluated. RESULTS The sensitivity of DCE-MRI, VEEG, and PET-CT was 59.64%, 76.51%, and 93.98%, respectively; the accuracy of DCE-MRI, VEEG, PET-CT, DCE-MRI combined with VEEG, and DCE-MRI combined with PET-CT was 57.58%, 67.72%, 91.03%, 91.23%, and 96.49%, respectively. Localization accuracy rate of the combination of DCE-MRI, VEEG, and PET-CT was 98.25% (56/57), which was higher than that of DCE-MRI combined with VEEG and of DCE-MRI combined with PET-CT. No statistical difference was found in the accuracy rate of localization between these three combined techniques. During the 12-month follow-up, children were grouped into Engles grade I (n=106), II (n=31), III (n=21), and IV (n=8) according to postoperative conditions. CONCLUSIONS All DCE-MRI combined with VEEG, DCE-MRI combined with PET-CT, and DCE-MRI combined with VEEG and PET-CT examinations have excellent accuracy in preoperative localization of epileptic foci and present excellent postoperative efficiency, suggesting that these combined imaging methods are suitable for serving as the reference basis in preoperative localization of epileptic foci in children with epilepsy.

Background and aim Diabetic neuropathic pain is a refractory and disabling complication of diabetes mellitus. The pathogenesis of the diabetic neuropathic pain is still unclear, and treatment is insufficient. The aim of this study is to investigate the roles of glucose-6-phosphate dehydrogenase (G6PD) and toll-like receptor 4 (TLR4) in neuropathic pain in rats with diabetes. Methods Type 1 diabetes model was induced by intraperitoneal injection of streptozotocin (STZ, 75 mg/kg) in adult female Sprague-Dawley rats. Paw withdrawal threshold and paw withdrawal latency of rats were measured by von Frey filaments and thermal radiation, respectively. The expressions of G6PD and TLR4 in L4-L6 dorsal root ganglions (DRGs) were measured by western blotting and quantitative real-time polymerase chain reaction analysis. Fluorescent immunohistochemistry was employed to detect expressions of G6PD and TLR4 and co-location of G6PD with TLR4. Results The mRNA and protein expression levels of G6PD in DRGs were significantly decreased in diabetic rats when compared with age-matched control rats. Upregulation of G6PD by intrathecal injection of G6PD overexpression adenovirus markedly attenuated hindpaw pain hypersensitivity of diabetic rats. The mRNA and protein expression levels of TLR4 in DRGs of diabetic rats were significantly increased when compared with control rats. Intrathecal injection of TLR4-selective inhibitor CLI-095 attenuated diabetic pain in dose- and time-dependent manners. Furthermore, G6PD and TLR4 were co-localized in DRG neurons. Intrathecal injection of G6PD overexpression adenovirus greatly reduced TLR4 expression, while intrathecal injection of CLI-095 had no significant effect on G6PD expression in diabetic rats. Conclusions Our results suggest that decrease in G6PD expression was involved in diabetic peripheral neuropathic pain, which was most likely through upregulation of TLR4 expression in the DRGs of rats.

This chapter describes for pain scientists and physicians a synopsis of the mechanisms of DNA methylation and demethylation as a background for understanding the gene processes of nociception and chronic pain. In particular, highlights of the following are included: the roles and functions of DNA methylation and demethylation and emerging technologies for studying DNA methylation. Following this, the potential roles and mechanisms of imbalance of the DNA methylation and demethylation homeostasis in chronic pain and its link to various types of chronic pain outcomes are particularly emphasized. The chapter concludes with a focus on research issues including methodological considerations that are key in interpreting research findings in DNA methylation in response to various pain conditions. Obviously, there are many challenging research issues that need to be well addressed to fill in the gaps in our knowledge related to the potential for drugging the pain epigenome.

Background/Aims This study was to investigate whether transforming growth factor-β1 (TGF-β1) plays a role in hyperalgesia in chronic pancreatitis (CP) and the underlying mechanisms. Methods CP was induced in male adult rats by intraductal injection of trinitrobenzene sulfonic acid (TNBS). Abdominal hyperalgesia was assessed by referred somatic behaviors to mechanical stimulation of rat abdomen. Dil dye injected into the pancreas was used to label pancreas-specific dorsal root ganglion (DRG) neurons. Whole cell patch clamp recordings and calcium imaging were performed to examine the effect of TGF-β1 on acutely isolated pancreas-specific DRG neurons. Western blot analysis was carried out to measure the expression of TGF-β1 and its receptors. Results TNBS injection significantly upregulated expression of TGF-β1 in the pancreas and DRGs, and TGF-β1 receptors in DRGs (T9-T13) in CP rats. Intrathecal injection of TGF-β receptor I antagonist SB431542 attenuated abdominal hyperalgesia in CP rats. TGF-β1 application depolarized the membrane potential and caused firing activity of DRG neurons. TGF-β1 application also reduced rheobase, hyperpolarized action potential threshold, and increased numbers of action potentials evoked by current injection of pancreas-specific DRG neurons. TGF-β1 application also increased the concentration of intracellular calcium of DRG neurons, which was inhibited by SB431542. Furthermore, intrathecal injection of TGF-β1 produced abdominal hyperalgesia in healthy rats. Conclusions These results suggest that TGF-β1 enhances neuronal excitability and increases the concentration of intracellular calcium. TGF-β1 and its receptors are involved in abdominal hyperalgesia in CP. This and future study might identify a potentially novel target for the treatment of abdominal pain in CP.

Background/Aims Patients with long-standing diabetes often demonstrate intestinal dysfunction and abdominal pain. However, the pathophysiology of abdominal pain in diabetic patients remains elusive. The purpose of study was to determine roles of voltage-gated sodium channels in dorsal root ganglion (DRG) in colonic hypersensitivity of rats with diabetes. Methods Diabetic models were induced by a single intraperitoneal injection of streptozotocin (STZ; 65 mg/kg) in adult female rats, while the control rats received citrate buffer only. Behavioral responses to colorectal distention were used to determine colonic sensitivity in rats. Colon projection DRG neurons labeled with DiI were acutely dissociated for measuring excitability and sodium channel currents by whole-cell patch clamp recordings. Western blot analysis was employed to measure the expression of NaV1.7 and NaV1.8 of colon DRGs. Results STZ injection produced a significantly lower distention threshold than control rats in responding to colorectal distention. STZ injection also depolarized the resting membrane potentials, hyperpolarized action potential threshold, decreased rheobase and increased frequency of action potentials evoked by 2 and 3 times rheobase and ramp current stimulation. Furthermore, STZ injection enhanced neuronal sodium current densities of DRG neurons innervating the colon. STZ injection also led to a significant upregulation of NaV1.7 and NaV1.8 expression in colon DRGs compared with age and sex-matched control rats. Conclusions Our results suggest that enhanced neuronal excitability following STZ injection, which may be mediated by upregulation of NaV1.7 and NaV1.8 expression in DRGs, may play an important role in colonic hypersensitivity in rats with diabetes.

Irritable bowel syndrome (IBS) is characterized by chronic visceral hypersensitivity that companied by altered bowel movement. However, the treatment options are very limited. The aim of this study was to investigate effects of electroacupuncture (EA) on visceral hypersensitivity in a rat model of IBS and to explore the underlying mechanisms of EA effects. Visceral hypersensitivity was established by neonatal maternal deprivation (NMD) in male rats on postnatal days 2 - 15. Behavioral experiments were conducted at the age of 7 weeks. Treatment with EA at Zusanli (stomach-36, ST-36) significantly reduced abdominal withdrawal reflex (AWR) scores in NMD rats but not in age-matched healthy control rats. In addition, EA treatment hyperpolarized resting membrane potentials, increased the rheobase and reduced the numbers of action potentials evoked by 2 and 3 times rheobase current stimulation of dorsal root ganglion (DRG) neurons innervating the colon. NMD markedly enhanced expression of TRPV1 in colon related DRGs while EA treatment drastically suppressed the expression of TRPV1 in DRGs of NMD rats. These data suggest that EA treatment produced an analgesic effect, which might be mediated at least in a part by suppression of TRPV1 expression and by inhibition of neuronal excitability of primary sensory neurons in rats with chronic visceral pain.

Aims The arcuate nucleus is a vital brain region for coursing of pain command. G protein-coupled kinase 6 (GRK6) accommodates signaling through G protein-coupled receptors. Studies have demonstrated that GRK6 is involved in inflammatory pain and neuropathic pain. The present study was designed to explore the role and the underlying mechanism of GRK6 in arcuate nucleus of chronic visceral pain. Methods Chronic visceral pain of rats was induced by neonatal maternal deprivation and evaluated by monitoring the threshold of colorectal distension. Western blotting, immunofluorescence, real-time quantitative polymerase chain reaction techniques, and Nissl staining were employed to determine the expression and mutual effect of GRK6 with nuclear factor κB (NF-κB). Results Expression of GRK6 in arcuate nucleus was significantly reduced in neonatal maternal deprivation rats when compared with control rats. GRK6 was mainly expressed in arcuate nucleus neurons, but not in astrocytes, and a little in microglial cells. Neonatal maternal deprivation reduced the percentage of GRK6-positive neurons of arcuate nucleus. Overexpression of GRK6 by Lentiviral injection into arcuate nucleus reversed chronic visceral pain in neonatal maternal deprivation rats. Furthermore, the expression of NF-κB in arcuate nucleus was markedly upregulated in neonatal maternal deprivation rats. NF-κB selective inhibitor pyrrolidine dithiocarbamate suppressed chronic visceral pain in neonatal maternal deprivation rats. GRK6 and NF-κB were expressed in the arcuate nucleus neurons. Importantly, overexpression of GRK6 reversed NF-κB expression at the protein level. In contrast, injection of pyrrolidine dithiocarbamate once daily for seven consecutive days did not alter GRK6 expression in arcuate nucleus of neonatal maternal deprivation rats. Conclusions Present data suggest that GRK6 might be a pivotal molecule participated in the central mechanisms of chronic visceral pain, which might be mediated by inhibiting NF-κB signal pathway. Overexpression of GRK6 possibly represents a potential strategy for therapy of chronic visceral pain.

Background Irritable bowel syndrome is one of the most common gastrointestinal disorders. It is featured by abdominal pain in conjunction with altered bowel habits. However, the pathophysiology of the syndrome remains largely unknown. Tumor necrosis factor receptor-associated factor 6 (TRAF6) has been reported to be involved in neuropathic pain. The aim of this study was to investigate roles and mechanisms of TRAF6 in the chronic visceral hypersensitivity. Methods Visceral hypersensitivity was induced by neonatal colonic inflammation and was identified by colorectal distention. The protein level, RNA level, and cellular distribution of TRAF6 and its related molecules were detected with Western blot, quantitative polymerase chain reaction, and immunofluorescence. In vitro spinal cord slice recording technique was performed to determine the synaptic transmission activities. Results Neonatal colonic inflammation rats displayed visceral hypersensitivity at the age of six weeks. The expression of TRAF6 was obviously upregulated in spinal cord dorsal horn of neonatal colonic inflammation rats at the age of six weeks. Immunofluorescence study showed that TRAF6 was dominantly expressed in spinal astrocytes. Intrathecal injection of TRAF6 small interfering RNA (siRNA) significantly reduced the amplitude of spontaneous excitatory postsynaptic currents at the spinal dorsal horn level. Furthermore, knockdown of TRAF6 led to a significant downregulation of cystathionine β synthetase expression in the spinal dorsal horn of neonatal colonic inflammation rats. Importantly, intrathecal injection of TRAF6 siRNA remarkably alleviated visceral hypersensitivity of neonatal colonic inflammation rats. Conclusions Our results suggested that the upregulation of TRAF6 contributed to visceral pain hypersensitivity, which is likely mediated by regulating cystathionine β synthetase expression in the spinal dorsal horn. Our findings suggest that TRAF6 might act as a potential target for the treatment of chronic visceral pain in irritable bowel syndrome patients.

Voltage-dependent anion channel 1 (VDAC1) is thought to contribute to the progression of tumor development. However, whether VDAC1 contributes to bone cancer pain remains unknown. In this study, we found that the expression of VDAC1 was upregulated in the L2-5 segments of the spinal dorsal horn at 2 and 3 weeks after injection of tumor cells into the tibial cavity. Intrathecal injection of a VDAC1 inhibitor significantly reversed the pain hypersensitivity and reduced the over-expression of Toll-like receptor 4 (TLR4). Intrathecal injection of minocycline, an inhibitor of microglia, also attenuated the pain hypersensitivity of rat models of bone cancer pain. These results suggest that VDAC1 plays a significant role in the development of complicated cancer pain, possibly by regulating the expression of TLR4.

Low back pain and sciatica are the most common symptoms of patients with lumbar disc herniation (LDH). The pathophysiology of lumbocrural pain and sciatica is not fully understood. The aim of the present study was to define the membrane properties and activities of voltage-gated sodium channels of dorsal root ganglion (DRG) neurons in a rat model of LDH. LDH was established by transplantation of autologous nucleus pulposus (NP) to lumbar 5 and 6 spinal nerves (L5–L6 DRG) of adult male rats. Mechanical paw withdrawal threshold (PWT) and thermal paw withdrawal latency (PWL) were measured 1 day before and through 35 days after transplantation of NP. Changes in expression of VGSCs were determined by western blotting. L5–L6 DRGs neurons innervating the hindpaw were labeled with DiI and acutely dissociated for measuring excitability and sodium channel currents under whole-cell patch clamp configurations. NP transplantation significantly reduced the PWT and PWL in association with a significant reduction in rheobase and an increase in numbers of action potentials evoked by 2X and 3X rheobase current stimulation. Voltage-gated sodium current density was significantly enhanced in L5–L6 DRG neurons from LDH rats. The inactivation curve showed a leftward shift in LDH rats while activation curve did not significantly alter. However, NP transplantation remarkably enhanced expression of NaV1.7 and NaV1.8 in L5–L6 DRGs but not in T10–12 DRGs. These data suggest that NP application produces pain-related behavior and potentiates sodium current density of DRG neurons, which is most likely mediated by enhanced expression of NaV1.7 and NaV1.8.

Purpose Allergic rhinitis (AR) is an inflammatory disorder of the upper airway. Exosomes or extracellular vesicles are nanosized vesicles of endosomal origin released from inflammatory and epithelial cells that have been implicated in allergic diseases. In this study, we characterized the microRNA (miRNA) content of exosomes in AR. Methods Extracellular vesicles were isolated from nasal mucus from healthy control subjects (n=10) and patients with severe AR (n=10). Vesicle RNA was analyzed by using a TaqMan microRNA assays Human Panel-Early Access kit (Applied Biosystems, Foster City, CA, USA) containing probes for 366 human miRNAs, and selected findings were validated with quantitative RT-PCR. Target prediction and pathway analysis for the differentially expressed miRNAs were performed using DIANA-mirPath. Results Twenty-one vesicle miRNAs were up-regulated and 14 miRNAs were under-regulated significantly (P

Abdominal pain and distention are major complaints in irritable bowel syndrome. Abdominal distention is mainly attributed to intraluminal retention of gas or solid contents, which may cause mechanical stress to the gut wall. Visceral hypersensitivity (VHS) may account for abdominal pain. We sought to determine whether tonic colon distention causes persistent VHS and if so whether mechanical stress-induced expression (mechanotranscription) of pain mediators in colonic smooth muscle cells (SMCs) plays a role in VHS. Human colonic SMCs were isolated and stretched in vitro to investigate whether mechanical stress upregulates expression of the pain mediator cyclooxygenase-2 (COX-2). Rat colon was distended with a 5-cm-long balloon, and gene expression of COX-2, visceromotor response (VMR), and sensory neuron excitability were determined. Static stretch of colonic SMCs induced marked expression of COX-2 mRNA and protein in a force- and time-dependent manner. Subnoxious tonic distention of the distal colon at ∼30–40 mmHg for 20 or 40 min induced COX-2 expression and PGE2 production in colonic smooth muscle, but not in the mucosa layer. Lumen distention also increased VMR in a force- and time-dependent manner. The increase of VMR persisted for at least 3 days. Patch-clamp experiments showed that the excitability of colon projecting sensory neurons in the dorsal root ganglia was markedly augmented, 24 h after lumen distention. Administration of COX-2 inhibitor NS-398 partially but significantly attenuated distention-induced VHS. In conclusion, tonic lumen distention upregulates expression of COX-2 in colonic SMC, and COX-2 contributes to persistent VHS.

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterized by chronic abdominal pain and alteration of bowel movements. The pathogenesis of visceral hypersensitivity in IBS patients remains largely unknown. Hydrogen sulfide (H2S) is reported to play an important role in development of visceral hyperalgesia. However, the role of H2S at spinal dorsal horn level remains elusive in visceral hypersensitivity. The aim of this study is designed to investigate how H2S takes part in visceral hypersensitivity of adult rats with neonatal colonic inflammation (NCI). Visceral hypersensitivity was induced by neonatal colonic injection of diluted acetic acid. Expression of an endogenous H2S synthesizing enzyme cystathionine β-synthetase (CBS) was determined by Western blot. Excitability and synaptic transmission of neurons in the substantia gelatinosa (SG) of spinal cord was recorded by patch clamping. Here, we showed that expression of CBS in the spinal dorsal horn was significantly upregulated in NCI rats. The frequency of glutamatergic synaptic activities in SG was markedly enhanced in NCI rats when compared with control rats. Application of NaHS increased the frequency of both spontaneous and miniature excitatory post-synaptic currents of SG neurons in control rats through a presynaptic mechanism. In contrast, application of AOAA, an inhibitor of CBS, dramatically suppressed the frequency of glutamatergic synaptic activities of SG neurons of NCI rats. Importantly, intrathecal injection of AOAA remarkably attenuated visceral hypersensitivity of NCI rats. These results suggest that H2S modulates pain signaling likely through a presynaptic mechanism in SG of spinal dorsal horn, thus providing a potential therapeutic strategy for treatment for chronic visceral pain in patients with IBS.

Aims It has been proved that cerebrospinal fluid (CSF) in the subarachnoid space could reenter the brain parenchyma via the perivascular space. The present study was designed to explore the pathway of subarachnoid CSF flux into the spinal cord and the potential role of aquaporin-4 (AQP4) in this process. Main methods Fluorescently tagged cadaverine, for the first time, was used to study CSF movement in mice. Following intracisternal infusion of CSF tracers, the cervical spinal cord was sliced and prepared for fluorescence imaging. Some sections were subject with immunostaining in order to observe tracer distribution and AQP4 expression. Key findings Fluorescently tagged cadaverine rapidly entered the spinal cord. Tracer influx into the spinal parenchyma was time dependent. At 10 min post-infusion, cadaverine was largely distributed in the superficial tissue adjacent to the pial surface. At 70 min post-infusion, cadaverine was distributed in the whole cord and especially concentrated in the gray matter. Furthermore, fluorescent tracer could enter the spinal parenchyma either along the perivascular space or across the pial surface. AQP4 was observed highly expressed in the astrocytic endfeet surrounding blood vessels and the pial surface. Blocking AQP4 by its specific inhibitor TGN-020 strikingly reduced the inflow of CSF tracers into the spinal cord. Significance Subarachnoid CSF could flow into the spinal cord along the perivascular space or across the pial surface, in which AQP4 is involved. Our observation provides a basis for the study on CSF movement in the spinal cord when some neurological diseases occur.

Background Although pain is one of the most distressing non-motor symptoms among patients with Parkinson's disease, the underlying mechanisms of pain in Parkinson's disease remain elusive. The aim of the present study was to investigate the role of serotonin (5-hydroxytryptamine) in the rostral ventromedial medulla (RVM) and spinal cord in pain sensory abnormalities in a 6-hydroxydopamine-treated rat model of Parkinson's disease. Methods The rotarod test was used to evaluate motor function. The radiant heat test and von Frey test were conducted to evaluate thermal and mechanical pain thresholds, respectively. Immunofluorescence was used to examine 5-hydroxytryptamine neurons and fibers in the rostral ventromedial medulla and spinal cord. High-performance liquid chromatography was used to determine 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels. Results The duration of running time on the rotarod test was significantly reduced in 6-hydroxydopamine-treated rats. Nociceptive thresholds of both mechanical and heat pain were reduced compared to sham-treated rats. In addition to the degeneration of cell bodies and fibers in the substantia nigra pars compacta, the number of rostral ventromedial medulla 5-hydroxytryptamine neurons and 5-hydroxytryptamine fibers in the spinal dorsal horn was dramatically decreased. 5-Hydroxytryptamine concentrations in both the rostral ventromedial medulla and spinal cord were reduced. Furthermore, the administration of citalopram significantly attenuated pain hypersensitivity. Interestingly, Intra-rostral ventromedial medulla (intra-RVM) microinjection of 5,7-dihydroxytryptamine partially reversed pain hypersensitivity of 6-hydroxydopamine-treated rats. Conclusions These results suggest that the decreased 5-hydroxytryptamine contents in the rostral ventromedial medulla and spinal dorsal horn may be involved in hyperalgesia in the 6-hydroxydopamine-induced rat model of Parkinson's disease.

Background Cancer-induced pain (CIP) is one of the most severe types of chronic pain with which clinical treatment remains challenging and the involved mechanisms are largely unknown. Suppressor of cytokine signaling 3 (SOCS3) is an important intracellular protein and provides a classical negative feedback loop, thus involving in a wide variety of processes including inflammation and nociception. However, the role of SOCS3 pathway in CIP is poorly understood. The present study was designed to investigate the role of SOCS3 in dorsal root ganglion (DRG) in the development of CIP. Method CIP was established by injection of Walker 256 mammary gland tumor cells into the rat tibia canal. Whole-cell patch clamping and Western blotting were performed. Results Following the development of bone cancer, SOCS3 expression was significantly downregulated in rat DRGs at L2–L5 segments. Overexpression of SOCS3, using lentiviral-mediated production of SOCS3 at spinal cord level, drastically attenuated mechanical allodynia and body weight-bearing difference, but not thermal hyperalgesia in bone cancer rats. In addition, overexpression of SOCS3 reversed the hyperexcitability of DRG neurons innervating the tibia, and reduced abnormal expression of toll-like receptors 4 in the DRGs. Conclusions These results suggest that SOCS3 might be a key molecular involved in the development of complicated cancer pain and that overexpression of SOCS3 might be an important strategy for treatment for mechanical allodynia associated with bone cancer.

Background Pain in patients with chronic pancreatitis is critical hallmark that accompanied inflammation, fibrosis, and destruction of glandular pancreas. Many researchers have demonstrated that stromal cell-derived factor 1 (also named as CXCL12) and its cognate receptor C-X-C chemokine receptor type 4 (CXCR4) involved in mediating neuropathic and bone cancer pain. However, their roles in chronic pancreatic pain remain largely unclear. Methods Chronic pancreatitis was induced by intraductal injection of trinitrobenzene sulfonic acid to the pancreas. Von Frey filament tests were conducted to evaluate pancreas hypersensitivity of rat. Expression of CXCL12, CXCR4, NaV1.8, and pERK in rat dorsal root ganglion was detected by Western blot analyses. Dorsal root ganglion neuronal excitability was assessed by electrophysiological recordings. Results We showed that both CXCL12 and CXCR4 were dramatically up-regulated in the dorsal root ganglion in trinitrobenzene sulfonic acid-induced chronic pancreatitis pain model. Intrathecal application with AMD3100, a potent and selective CXCR4 inhibitor, reversed the hyperexcitability of dorsal root ganglion neurons innervating the pancreas of rats following trinitrobenzene sulfonic acid injection. Furthermore, trinitrobenzene sulfonic acid-induced extracellular signal-regulated kinase activation and Nav1.8 up-regulation in dorsal root ganglias were reversed by intrathecal application with AMD3100 as well as by blockade of extracellular signal-regulated kinase activation by intrathecal U0126. More importantly, the trinitrobenzene sulfonic acid-induced persistent pain was significantly suppressed by CXCR4 and extracellular signal-regulated kinase inhibitors. Conclusions The present results suggest that the activation of CXCL12-CXCR4 signaling might contribute to pancreatic pain and that extracellular signal-regulated kinase-dependent Nav1.8 up-regulation might lead to hyperexcitability of the primary nociceptor neurons in rats with chronic pancreatitis.

The present study was designed to investigate the roles of P2X3 receptors in dorsal root ganglion (DRG) neurons in colonic hypersensitivity and the effects of alpha-lipoic acid (ALA) on P2X3 receptor activity and colonic hypersensitivity of diabetic rats. Streptozotocin (STZ) was used to induce diabetic model. Abdominal withdrawal reflex (AWR) responding to colorectal distention (CRD) was recorded as colonic sensitivity. ATP-induced current density of colon-specific DRG (T13-L2 DRGs) neurons was measured with whole-cell patch clamp. The expression of P2X3Rs of T13-L2 DRGs was measured by western blot analysis. The results showed that AWR scores significantly increased after STZ injection. P2X3R expression and ATP current density of T13-L2 DRG neurons were enhanced in diabetic rats. Intraperitoneal injection with ALA once a day for 1 week remarkably reduced P2X3R expression and ATP current density in diabetic rats. Importantly, ALA treatment attenuated colonic hypersensitivity in diabetic rats. Our data suggest that STZ injection increases expression and function of P2X3 receptors of colon-specific DRG neurons, thus contributing to colonic hypersensitivity in diabetic rats. Administration of ALA attenuates diabetic colonic hypersensitivity, which is most likely mediated by suppressing expression and function of P2X3 receptors in DRGs of diabetic rats.

Background Pain is the main symptom of patients with rheumatoid arthritis (RA). Reports of the effects of moxibustion on patients with rheumatoid arthritis have reached various conclusions. The aim of this meta-analysis was to evaluate the effect of moxibustion on pain in patients with RA. Methods A systematic search of MEDLINE, EMBASE, the Cochrane Library, and the Chinese databases Wan Fang Med Database, CNKI, and VIP (until November, 2018) was used to identify studies reporting pain (on a visual analogue scale (VAS)), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and rheumatoid factor (RF) levels, response rate, and the ACR50 rate in patients with RA. Results were expressed as mean difference (MD) and 95% confidence intervals (CI). Results Six studies involving 281 participants were included. Moxibustion had significant effects on pain (VAS: MD = -0.53, 95% CI [-0.94, -0.12], P =.01). Moreover, moxibustion had effects on CRP (MD = -2.84, 95% CI [-5.13, -0.55], P =.01), ESR (MD = -8.44, 95% CI ([-13.19, -3.68], P =.0005), and RF (MD = -6.39, 95% CI [-18.57, 5.79], P =.30). Additionally, it had effects on response rate (n = 249, RR = 1.26, 95% CI [1.11, 1.43], P =.0004) and ACR50 rate (n = 140, RR = 1.44, 95% CI [1.11, 1.88], P =.007). Conclusion We found that moxibustion with Western medicine therapy is superior to Western medicine therapy alone for pain in patients with RA. Moxibustion had significant effects on pain in patients with RA, but the effects of moxibustion on inflammatory factors in RA were unclear.

Background The pathogenesis of pain in irritable bowel syndrome (IBS) is poorly understood and treatment remains difficult. We have previously reported that TTX-resistant (TTX-R) sodium channels in colon-specific dorsal root ganglion (DRG) neurons were sensitized and the expression of the endogenous hydrogen sulfide producing enzyme cystathionine β-synthetase (CBS) was upregulated in a rat model of visceral hypersensitivity induced by neonatal maternal deprivation (NMD). However, the detailed molecular mechanism for activation of sodium channels remains unknown. This study was designed to examine roles for CBS–H 2 S signaling in sensitization of sodium channels in a previously validated rat model of IBS. Methods Neonatal male rats (postnatal days 2–15) were exposed to a 3 hour period of daily maternal separation with temperature maintained at ~ 33 °C. Colon-specific dorsal root ganglion (DRG) neurons were labeled with DiI and acutely dissociated for measuring excitability and sodium channel current under whole-cell patch clamp configurations. The expression of Na V 1.8 was analyzed by Western blot and Immunofluorescence study. The endogenous H 2 S producing enzyme CBS antagonist was injected intraperitoneally. Results We showed that CBS was colocalized with Na V 1.8 in colon-specific DRG neurons pre-labeled with DiI. Pretreatment of O -(Carboxymethyl) hydroxylamine hemihydrochloride (AOAA), an inhibitor of CBS, significantly reduced expression of Na V 1.8 in NMD rats. AOAA treatment also inhibited the TTX-R sodium current density, right-shifted the V 1/2 of activation curve, and reversed hyperexcitability of colon-specific DRG neurons in NMD rats. Conversely, addition of NaHS, a donor of H 2 S, greatly enhanced TTX-R sodium current density, left shifted the activation curve and enhanced excitability of colon DRG neurons in age-matched healthy rats. Furthermore, application of H-89, an inhibitor of protein kinase A, markedly attenuated the potentiation of TTX-R sodium current density by NaHS. Conclusion These data suggest that sensitization of sodium channels of colon DRG neurons in NMD rats is most likely mediated by CBS–H 2 S signaling, thus identifying a potential target for treatment for chronic visceral pain in patients with IBS.

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterized by abdominal pain in association with altered bowel movements. The underlying mechanisms of visceral hypersensitivity remain elusive. This study was designed to examine the role for sodium channels in a rat model of chronic visceral hyperalgesia induced by neonatal maternal deprivation (NMD). Abdominal withdrawal reflex (AWR) scores were performed on adult male rats. Colon-specific dorsal root ganglion (DRG) neurons were labeled with DiI and acutely dissociated for measuring excitability and sodium channel current under whole-cell patch-clamp configurations. The expression of NaV1.8 was analyzed by Western blot and quantitative real-time PCR. NMD significantly increased AWR scores, which lasted for ∼6 wk in an association with hyperexcitability of colon DRG neurons. TTX-resistant but not TTX-sensitive sodium current density was greatly enhanced in colon DRG neurons in NMD rats. Compared with controls, activation curves showed a leftward shift in NMD rats whereas inactivation curves did not differ significantly. NMD markedly accelerated the activation time of peak current amplitude without any changes in inactivation time. Furthermore, NMD remarkably enhanced expression of NaV1.8 at protein levels but not at mRNA levels in colon-related DRGs. The expression of NaV1.9 was not altered after NMD. These data suggest that NMD enhances TTX-resistant sodium activity of colon DRG neurons, which is most likely mediated by a leftward shift of activation curve and by enhanced expression of NaV1.8 at protein levels, thus identifying a specific molecular mechanism underlying chronic visceral pain and sensitization in patients with IBS.

Summary Aims To investigate whether electroacupuncture (EA) produced analgesic effect and whether nuclear factor kappa B (NF-κB) and cystathionine β synthase (CBS) involved in EA-mediated analgesia in painful diabetic neuropathy in rats. Methods Diabetes was induced by an intraperitoneal injection of streptozotocin (STZ) in adult female rats. Mechanical pain threshold was measured by von Frey filaments. EA was applied at acupoint Zu-San-Li (ST-36) in both hindlimbs. Western blot analysis was employed to detect changes in protein levels of NF-κB and CBS in spinal dorsal root ganglion (DRGs). Results Mechanical allodynia was developed 2 weeks after STZ injection and lasted for another 4 weeks. STZ injection significantly enhanced expression of p65 and CBS in lumbar L4-6 DRGs when compared with age-matched controls. EA markedly attenuated mechanical allodynia. Importantly, EA treatment remarkably inhibited p65 and CBS expression in DRGs. Additionally, intrathecal injection of the p65 antagonist pyrrolidine dithiocarbamate attenuated mechanical allodynia and markedly inhibited CBS expression in DRGs in STZ rats. Conclusions These data indicate that EA produced an analgesic effect, which might be mediated at least in a part by inhibition of NF-κB signaling pathway in primary sensory neurons in rats with diabetes.

Aims Insular cortex (IC) is involved in processing the information of pain. The aim of this study was to investigate roles and mechanisms of P2X7 receptors (P2X7Rs) in IC in development of visceral hypersensitivity of adult rats with neonatal maternal deprivation (NMD). Methods Visceral hypersensitivity was quantified by abdominal withdrawal reflex threshold to colorectal distension (CRD). Expression of P2X7Rs was determined by qPCR and Western blot. Synaptic transmission in IC was recorded by patch-clamp recording. Results The expression of P2X7Rs and glutamatergic neurotransmission in IC was significantly increased in NMD rats when compared with age-matched controls. Application of BzATP (P2X7R agonist) enhanced the frequency of spontaneous excitatory postsynaptic currents (sEPSC) and miniature excitatory postsynaptic currents (mEPSC) in IC slices of control rats. Application of BBG (P2X7R antagonist) suppressed the frequencies of sEPSC and mEPSC in IC slices of NMD rats. Microinjection of BzATP into right IC significantly decreased CRD threshold in control rats while microinjection of BBG or A438079 into right IC greatly increased CRD threshold in NMD rats. Conclusion Data suggested that the enhanced activities of P2X7Rs in IC, likely through a presynaptic mechanism, contributed to visceral hypersensitivity of adult rats with NMD.

The central mechanisms of visceral hypersensitivity remain largely unknown. It’s reported that there are highest densities of TRPV1 labeled neurons within basolateral amygdala (BLA). The aim of this study was to explore the role and mechanisms of TRPV1 in BLA in development of visceral hypersensitivity. Visceral hypersensitivity was induced by neonatal maternal deprivation (NMD) and was quantified by abdominal withdrawal reflex. Expression of TRPV1 was determined by Western blot. The synaptic transmission of neurons in BLA was recorded by patch clamping. It was found that the expression of TRPV1 in BLA was significantly upregulated in NMD rats; glutamatergic synaptic activities in BLA were increased in NMD rats; application of capsazepine (TRPV1 antagonist) decreased glutamatergic synaptic activities of BLA neurons in NMD slices through a presynaptic mechanism; application of capsaicin (TRPV1 agonist) increased glutamatergic synaptic activities of BLA neurons in control slices through presynaptic mechanism without affecting GABAergic synaptic activities; microinjecting capsazepine into BLA significantly increased colonic distension threshold both in control and NMD rats. Our data suggested that upregulation of TRPV1 in BLA contributes to visceral hypersensitivity of NMD rats through enhancing excitation of BLA, thus identifying a potential target for treatment of chronic visceral pain.

This paper analyzes the characteristics of waste resources and utilization status, information technology the role and utilization status in the waste resources management, put forward using 3S technology (GIS, RS, GPS), Internet technology, data sharing technology and a variety of statistical and management software to establish the Waste Resource Management Information System, this system covers the waste resources information which about the waste resources from the "cradle" to "grave" life cycle,so as to improve waste resources management level, and provide support for its utilization.Solve the problem in the course of waste resources convert into energy. Provide information support for the waste resources conversion technology large-scale commercial application, accelerate the commercial development process.Provide up-to-date information on the opportunities for growing crops for energy and using farm residues, achieve to modernization of waste resource management, improve the level of waste resource management,provide independent information and advice to agriculture, academia, Government, industry, the media and the public.

On the basis of the study on the expressway management business flow as well as the SOA architecture concept, this paper designs the overall framework for a systematical expressway management information platform, which includes network of 3 levels, grading processing, comprehensive monitoring, comprehensive information application management, web portal and security system, and then designs the overall technical frame of this platform. Road administration is the core part of highway administration and the concentrated reflection of external highway administrative management. In addition to the approval of highway property, construction, maintenance and management, its main contents also involve the highway maintenance, highway entrance fee management and other road maintenance. It covers a wide range and there is so much information of deferent types to be processed and used. Although domestic and foreign roads and road administration departments have some information management systems in use, some are special highway road administration information systems[1,2], and some are highway comprehensive information management systems[3], the integrated comprehensive highway information management contents are lack of research, and the professional, comprehensive, open road administration information platform has not been established yet. Therefore, the author conducted the design of constructing advanced road administration information platform structure. This platform uses the service oriented architecture (SOA), integrates advanced information network technology, data communications monitoring and transmission technology, electronic control technology, computer processing technique with 3S, PDA and other advanced technologies, so that it is effectively integrated and used in the highway information management. The construction of the platform will realize the effective and scientific management for highways business, ensuring that the highways are unblocked, and maintaining the road property and rights of highways, thus promoting the development of the industrial management information.

By analyzing the typical operational pattern of agricultural products logistics, the agricultural products logistics operational pattern based on information share was built. The pattern was demonstrated by the watermelon logistics operational pattern based on information share. The result showed that the pattern was effective and practicable.