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Guo Y, Gharibani P. Analgesic Effects of Vagus Nerve Stimulation on Visceral Hypersensitivity: A Direct Comparison Between Invasive and Noninvasive Methods in Rats. Neuromodulation 2024; 27:284-294. [PMID: 37191611 DOI: 10.1016/j.neurom.2023.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 03/20/2023] [Accepted: 04/10/2023] [Indexed: 05/17/2023]
Abstract
OBJECTIVES The aims of this study were to investigate analgesic effects of vagus nerve stimulation (VNS) on visceral hypersensitivity (VH) in a rodent model of functional dyspepsia (FD) and to compare invasive VNS with noninvasive auricular VNS (aVNS). MATERIALS AND METHODS Eighteen ten-day-old male rats were gavaged with 0.1% iodoacetamide (IA) or 2% sucrose solution for six days. After eight weeks, IA-treated rats were implanted with electrodes for VNS or aVNS (n = 6 per group). Different parameters, varying in frequency and stimulation duty cycle, were tested to find the best parameter based on the improvement of VH assessed by electromyogram (EMG) during gastric distension. RESULTS Compared with sucrose-treated rats, visceral sensitivity was increased significantly in IA-treated "FD" rats and ameliorated remarkably by VNS (at 40, 60, and 80 mm Hg; p ≤ 0.02, respectively) and aVNS (at 60 and 80 mm Hg; p ≤ 0.05, respectively) with the parameter of 100 Hz and 20% duty cycle. There was no significant difference in area under the curve of EMG responses between VNS and aVNS (at 60 and 80 mm Hg, both p > 0.05). Spectral analysis of heart rate variability revealed a significant enhancement in vagal efferent activity while applying VNS/aVNS compared with sham stimulation (p < 0.01). In the presence of atropine, no significant differences were noted in EMG after VNS/aVNS. Naloxone blocked the analgesic effects of VNS/aVNS. CONCLUSIONS VNS/aVNS with optimized parameter elicits ameliorative effects on VH, mediated by autonomic and opioid mechanisms. aVNS is as effective as direct VNS and has great potential for treating visceral pain in patients with FD.
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Affiliation(s)
- Yu Guo
- Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Payam Gharibani
- Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Division of Neuroimmunology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Sun J, Zhang M, Liu W, Liu Y, Zhang D, Fan X, Zhang J, Li T, Lu M. Evaluation of the effectiveness and mechanism of action of the Chang-Kang-Fang formula combined with bifid triple viable capsules on diarrhea-predominant irritable bowel syndrome. Front Microbiol 2023; 14:1160783. [PMID: 37440881 PMCID: PMC10333534 DOI: 10.3389/fmicb.2023.1160783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 05/23/2023] [Indexed: 07/15/2023] Open
Abstract
Introduction The Chang-Kang-Fang (CKF) formula, a traditional Chinese herbal formula, can decrease serotonin (5-HT) levels and treat irritable bowel syndrome (IBS). Probiotics have a better synergistic effect on diarrhea-predominant IBS (IBS-D) when combined with 5-HT3 receptor antagonists. The present study aimed to elucidate the efficacy and the mechanisms of action of the CKF formula combined with bifid triple viable capsules (PFK) against IBS-D. Methods The rat models of IBS-D were induced by gavage with senna decoction plus restraint stress. The CKF formula, PFK and their combination were administered to the rats. Their effects were evaluated based on general condition of the rats and the AWR score. The levels of 5-HT and fos protein in the colon and hippocampus were measured by immunohistochemistry. The levels of SP and VIP, as well as ZO-1 and occludin in the colon, were determined by enzyme-linked immunosorbent assay and immunohistochemistry. The intestinal microbiota in faeces was analyzed by 16S rRNA high-throughput sequencing. Results The results showed that the oral CKF formula combined with PFK (CKF + PFK) could significantly relieve the symptoms of IBS-D, including elevating the weight rate and decreasing the AWR score. Compared with the MC group, administration of CKF + PFK significantly reduced the expression of fos in the colon and hippocampus and that of 5-HT, SP and VIP in the colon and increased the levels of 5-HT in the hippocampus and ZO-1 and occludin in the colon. The above indexes exhibited statistical significance in the CKF + PFK group relative to those in the other groups. Moreover, treatment with CKF + PFK improved the diversity of intestinal microbiota and the abundance of Firmicutes, Lachnospiraceae and Ruminococcaceae but decreased those of Bacteroidetes and Prevotellaceae. Conclusions The CKF formula combined with PFK may have a synergistic effect on IBS-D by slowing gastrointestinal motility, lowering visceral hypersensitivity, enhancing the intestinal barrier function and modulating the composition of intestinal microbiota.
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Affiliation(s)
- Jing Sun
- Department of Central laboratory, Nanjing Lishui District Hospital of Traditional Chinese Medicine, Nanjing, China
- Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Mengqiu Zhang
- School of Third Clinical Medicine, Nanjing University of Chinese Medicine, Nanjing, China
- Suqian Hospital of Traditional Chinese Medicine, Suqian, China
| | - Wei Liu
- School of Third Clinical Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Youqian Liu
- Department of Gastroenterology, Nanjing Lishui District Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Dongjian Zhang
- School of Third Clinical Medicine, Nanjing University of Chinese Medicine, Nanjing, China
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Xinyu Fan
- Department of Gastroenterology, Nanjing Lishui District Hospital of Traditional Chinese Medicine, Nanjing, China
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Jian Zhang
- School of Third Clinical Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Tian Li
- Department of Central laboratory, Nanjing Lishui District Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Min Lu
- School of Third Clinical Medicine, Nanjing University of Chinese Medicine, Nanjing, China
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Sun Q, Zhang S, Zhang BY, Zhang Y, Yao L, Hu J, Zhang HH. microRNA-181a contributes to gastric hypersensitivity in rats with diabetes by regulating TLR4 expression. Mol Pain 2023; 19:17448069231159356. [PMID: 36750423 PMCID: PMC9989404 DOI: 10.1177/17448069231159356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Aim: The aim of this study is to investigate the mechanism and interaction of microRNA-181a (miR-181a), toll-like receptor 4 (TLR4) and nuclear factor-kappa B (NF-κB) in gastric hypersensitivity in diabetic rats. Methods: Diabetes was induced by a single intraperitoneal injection of streptozotocin (STZ; 65 mg/kg) in female SD rats. Gastric balloon distension technique was used to measure diabetic gastric hypersensitivity. Gastric-specific (T7-T10) dorsal root ganglion (DRG) neurons were acutely dissociated to measure excitability with patch-clamp techniques. Western blotting was employed to measure the expressions of TLR4, TRAF6 and NF-κB subunit p65 in T7-T10 DRGs. The expressions of microRNAs in T7-T10 DRGs were measured with quantitative real-time PCR and fluorescence in situ hybridization. Dual-luciferase reporter gene assay was used to detect the targeting regulation of microRNAs on TLR4. Results: (1) Diabetic rats were more sensitive to graded gastric balloon distention at 2 and 4 weeks. (2) The expression of TLR4 was significantly up-regulated in T7-T10 DRGs of diabetic rats. Intrathecal injection of CLI-095 (TLR4-selective inhibitor) attenuated diabetic gastric hypersensitivity, and markedly reversed the hyper-excitability of gastric-specific DRG neurons. (3) The expressions of miR-181a and miR-7a were significantly decreased in diabetic rats. MiR-181a could directly regulate the expression of TLR4, while miR-7a couldn't. (4) Intrathecal injection of miR-181a agomir down-regulated the expression of TLR4, reduced the hyper-excitability of gastric-specific neurons, and alleviated gastric hypersensitivity. (5) p65 and TLR4 were co-expressed in Dil-labeled DRG neurons. (6) Inhibition of p65 attenuated diabetic gastric hypersensitivity and hyper-excitability of gastric-specific DRG neurons. (7) The expression of TRAF6 was significantly up-regulated in diabetic rats. CLI-095 treatment also reduced the expression of TRAF6 and p65. Conclusion: The reduction of microRNA-181a in T7-T10 DRGs might up-regulate TLR4 expression. TLR4 activated NF-κB through MyD88-dependent signaling pathway, increased excitability of gastric-specific DRG neurons, and contributed to diabetic gastric hypersensitivity.
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Affiliation(s)
- Qian Sun
- Center for Translational Pain Medicine, Institute of Neuroscience, 12582Soochow University, Suzhou, China
| | - Shiyu Zhang
- Department of Endocrinology, the Second Affiliated Hospital, 12582Soochow University, Suzhou, China
| | - Bing-Yu Zhang
- Department of Emergency, 199193The Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Yilian Zhang
- Department of Endocrinology, the Second Affiliated Hospital, 12582Soochow University, Suzhou, China
| | - Lijun Yao
- Department of Endocrinology, 602846The Affiliated Haian Hospital of Nantong University, Nantong, China
| | - Ji Hu
- Department of Endocrinology, the Second Affiliated Hospital, 12582Soochow University, Suzhou, China
| | - Hong-Hong Zhang
- Department of Endocrinology, the Second Affiliated Hospital, 12582Soochow University, Suzhou, China.,Clinical Research Center of Neurological Disease, 12582The Second Affiliated Hospital of Soochow University, Suzhou, China
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Ji S, You Y, Peng B, Zhong T, Kuang Y, Li S, Du L, Chen L, Sun X, Dai J, Huang S, Wu Y, Liu Y. Multi-omics analysis reveals the metabolic regulators of duodenal low-grade inflammation in a functional dyspepsia model. Front Immunol 2022; 13:944591. [PMID: 36091013 PMCID: PMC9453867 DOI: 10.3389/fimmu.2022.944591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 07/28/2022] [Indexed: 11/27/2022] Open
Abstract
Several gastrointestinal phenotypes and impairment of duodenal mucosal barrier have been reported in clinical studies in patients with functional dyspepsia (FD). Due to the preferential colonization of the mucosa, intestinal microbes and their metabolites are commonly involved in host metabolism and immune responses. However, there are no studies on the intertwined correlation among multi-level data. For more comprehensive illustrating, a multi-omics analysis focusing on the duodenum was performed in the FD rat model. We found that differential microbiomes in the duodenum were significantly correlated with the biosynthesis of lipopolysaccharide and peptidoglycan. The innate immune response-related genes, which were upregulated in the duodenum, were associated with the TLR2/TLR4-NFκB signaling pathway. More importantly, arachidonyl ethanolamide (anandamide, AEA) and endocannabinoid analogues showed linear relationships with the FD phenotypes. Taken together, multi-level data from microbiome, transcriptome and metabolome reveal that AEA may regulate duodenal low-grade inflammation in FD. These results suggest an important cue of gut microbiome–endocannabinoid system axis in the pathogenesis of FD.
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Affiliation(s)
- Shuai Ji
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Yanting You
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Baizhao Peng
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Tianyu Zhong
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Yuxiang Kuang
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Shasha Li
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Lijing Du
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Liqian Chen
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Xiaomin Sun
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Jiaojiao Dai
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Suiping Huang
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China
- *Correspondence: Yanyan Liu, ; Yuyao Wu, ; Suiping Huang,
| | - Yuyao Wu
- Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
- *Correspondence: Yanyan Liu, ; Yuyao Wu, ; Suiping Huang,
| | - Yanyan Liu
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
- *Correspondence: Yanyan Liu, ; Yuyao Wu, ; Suiping Huang,
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5
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Cordner ZA, Li Q, Liu L, Tamashiro KL, Bhargava A, Moran TH, Pasricha PJ. Vagal gut-brain signaling mediates amygdaloid plasticity, affect, and pain in a functional dyspepsia model. JCI Insight 2021; 6:144046. [PMID: 33591956 PMCID: PMC8026195 DOI: 10.1172/jci.insight.144046] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 02/10/2021] [Indexed: 12/11/2022] Open
Abstract
Functional dyspepsia (FD) is associated with chronic gastrointestinal distress and with anxiety and depression. Here, we hypothesized that aberrant gastric signals, transmitted by the vagus nerve, may alter key brain regions modulating affective and pain behavior. Using a previously validated rat model of FD characterized by gastric hypersensitivity, depression-like behavior, and anxiety-like behavior, we found that vagal activity - in response to gastric distention - was increased in FD rats. The FD phenotype was associated with gastric mast cell hyperplasia and increased expression of corticotrophin-releasing factor (Crh) and decreased brain-derived neurotrophic factor genes in the central amygdala. Subdiaphragmatic vagotomy reversed these changes and restored affective behavior to that of controls. Vagotomy partially attenuated pain responses to gastric distention, which may be mediated by central reflexes in the periaqueductal gray, as determined by local injection of lidocaine. Ketotifen, a mast cell stabilizer, reduced vagal hypersensitivity, normalized affective behavior, and attenuated gastric hyperalgesia. In conclusion, vagal activity, partially driven by gastric mast cells, induces long-lasting changes in Crh signaling in the amygdala that may be responsible for enhanced pain and enhanced anxiety- and depression-like behaviors. Together, these results support a "bottom-up" pathway involving the gut-brain axis in the pathogenesis of both gastric pain and psychiatric comorbidity in FD.
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Affiliation(s)
| | - Qian Li
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Liansheng Liu
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | | - Aditi Bhargava
- Department of Obstetrics and Gynecology and The Center for Reproductive Sciences, UCSF, San Francisco, California, USA
| | | | - Pankaj Jay Pasricha
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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6
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Sini-San Regulates the NO-cGMP-PKG Pathway in the Spinal Dorsal Horn in a Modified Rat Model of Functional Dyspepsia. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2020; 2020:3575231. [PMID: 32328126 PMCID: PMC7150674 DOI: 10.1155/2020/3575231] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 03/01/2020] [Accepted: 03/10/2020] [Indexed: 02/06/2023]
Abstract
The present study investigated the effect of Chinese medicine Sini-San (SNS) on visceral hypersensitivity in a rat model of functional dyspepsia (FD), and it explored related underlying mechanisms. The rat model of FD was developed by combining neonatal iodoacetamide (IA) treatment and adult tail-clamping. After SNS treatment, the behavior and electromyographic testing were performed to evaluate the visceromotor responses of rats to gastric distention. Immunofluorescence was used to detect the distribution of iNOS-positive cells in the spinal dorsal horn, while the real-time quantitative PCR and western blot were used for detection of the gene expression of c-fos, iNOS, and GABAb and protein levels of iNOS and GABAb in the spinal dorsal horn, respectively. The protein concentration of cGMP and PKG proteins in the spinal dorsal horn were quantified by enzyme-linked immunosorbent assay. In this study, SNS treatment significantly reduced the behavioral score and electromyographic response to graded intragastric distension pressure. The middle-dose of SNS treatment significantly reduced the distribution of iNOS-positive cells in the spinal dorsal horn of FD model rats. The gene expression of c-fos, iNOS, and GABAb and the protein contents of iNOS, GABAb, cGMP, and PKG in the spinal dorsal horn of FD model rats were restored to a normal level by middle-dose of SNS treatment. Our results suggest that Sini-San may alleviate the visceral hypersensitivity in FD model rats via regulation of the NO/cGMP/PKG pathway in the spinal dorsal horn.
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Ouyang X, Li S, Zhou J, Chen JDZ. Electroacupuncture Ameliorates Gastric Hypersensitivity via Adrenergic Pathway in a Rat Model of Functional Dyspepsia. Neuromodulation 2020; 23:1137-1143. [DOI: 10.1111/ner.13154] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 02/27/2020] [Accepted: 03/16/2020] [Indexed: 12/15/2022]
Affiliation(s)
- Xiaojun Ouyang
- Veterans Research and Education Foundation, Oklahoma City VA Health Care System OK USA
- Institute of Geriatrics, Jiangsu Province Official Hospital Nanjing Jiangsu China
| | - Shiying Li
- Veterans Research and Education Foundation, Oklahoma City VA Health Care System OK USA
- Division of Gastroenterology and Hepatology Johns Hopkins University Baltimore MD USA
| | - Jingzhu Zhou
- Veterans Research and Education Foundation, Oklahoma City VA Health Care System OK USA
- Department of Acupuncture and Moxibustion The First Affiliated Hospital of Nanjing Medical University Nanjing Jiangsu China
| | - Jiande DZ Chen
- Division of Gastroenterology and Hepatology Johns Hopkins University Baltimore MD USA
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Shafigh-Ardestani MH, Karami-Horestani M, Emami B, Arjmandpour A. Evaluating the Effect of Oral Gabapentin on the Improvement of Gastrointestinal Symptoms in Patients with Functional Dyspepsia Resistant to Conventional Treatments. Adv Biomed Res 2019; 8:53. [PMID: 31516891 PMCID: PMC6712892 DOI: 10.4103/abr.abr_234_18] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background: Dyspepsia is one of the most common gastrointestinal (GI) problems and is more prevalent in adults. Environmental hypersensitivity and anxiety and depression are among the factors that can cause this disease. In this regard, gabapentin as a gamma-aminobutyric acid (GABA) analog used in the treatment of neuropathic pain and may be effective in controlling the symptoms of GI disorders. Therefore, the present study aimed to evaluate the effect of oral gabapentin on the improvement of GI symptoms in patients with functional dyspepsia (FD) resistant to conventional treatments. Materials and Methods: In a double-blind clinical trial, 126 patients with FD resistant to conventional treatments, referred to gastroenterology clinic of Hajar Hospital of Shahrekord in 2017–2018, were randomly assigned to two groups; patients in the control group received omeprazole alone, and the case group received omeprazole plus gabapentin. The severity of GI symptoms was recorded and evaluated by the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire before and after treatment (4 weeks). Results: GSRS total score in the group who received gabapentin (16.89 ± 6.89) was significantly lower than controls (20.00 ± 9.31) (P = 0.036). It also found that gabapentin, as an adjunctive drug, plus omeprazole could play a significant role in GI symptom improvement, such as pain, reflux, and indigestion. Conclusion: Gabapentin as an adjunctive drug could be more effective in reducing the severity of GI symptoms in patients with dyspepsia, especially neurological symptoms (such as pain, reflux, and indigestion).
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Affiliation(s)
| | - Mohammad Karami-Horestani
- Department of Gastrointestinal and Liver Disease, Sharekord University of Medical Sciences, Shahrekord, Iran
| | - Behrokh Emami
- Department of Internal Medicine, Sharekord University of Medical Sciences, Shahrekord, Iran
| | - Akbar Arjmandpour
- Department of Gastrointestinal and Liver Disease, Najafabad Islamic Azad University, Isfahan, Iran
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Dong Y, Li S, Yin J, Chen JDZ. Ameliorating effects of optimized gastric electrical stimulation and mechanisms involving nerve growth factor and opioids in a rodent model of gastric hypersensitivity. Neurogastroenterol Motil 2019; 31:e13551. [PMID: 30790401 DOI: 10.1111/nmo.13551] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 12/09/2018] [Accepted: 12/20/2018] [Indexed: 02/08/2023]
Abstract
BACKGROUND Gastric electrical stimulation (GES) has been applied to treat gastric motility disorders for decades. This study was designed to investigate the effects and mechanisms of GES for visceral hypersensitivity in a rodent model of functional dyspepsia (FD). METHODS Male Sprague-Dawley rat pups at 10-days old received 0.1% iodoacetamide (IA) daily for 6 days. The experiments were performed when the rats reached 8-11 weeks of age, and visceral hypersensitivity was established. Then, GES parameters were optimized and the chronic effects of GES on gastric hypersensitivity were assessed by electromyogram (EMG). Naloxone (3 mg/kg), D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP, 1 mg/kg), and anti-NGF (16 μg/kg) were individually intraperitoneally injected to investigate opioid and nerve growth factor (NGF) mechanisms. Tissues were analyzed for NGF expression. KEY RESULTS In the IA-treated rats, the visceromotor response to gastric distension was significantly increased, and both acute GES with optimized stimulation parameters (0.25 seconds on, 0.25 seconds off, 100 Hz, 0.25 ms, 6 mA) and chronic GES (7 days, 2 hours/day) normalized gastric hypersensitivity. The inhibitory effect of GES on gastric hypersensitivity was blocked by naloxone and CTOP. Anti-NGF normalized EMG responses in IA-treated rats. The expressions of NGF in the tissues of IA-treated rats were dramatically increased, and these increases were suppressed with GES. CONCLUSIONS AND INFERENCES GES with optimized parameters improves gastric hypersensitivity induced by neonatal treatment of IA mediated peripherally by suppressing NGF and via the opioid mechanism involving the µ receptor. GES as a potential therapy for treating visceral pain may be explored in clinical studies.
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Affiliation(s)
- Yan Dong
- Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, Oklahoma.,Institute of Chinese Traditional Surgery, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Shiying Li
- Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, Oklahoma.,Division of Gastroenterology and Hepatology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jieyun Yin
- Division of Gastroenterology and Hepatology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jiande D Z Chen
- Division of Gastroenterology and Hepatology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
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10
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Choosing an Animal Model for the Study of Functional Dyspepsia. Can J Gastroenterol Hepatol 2018; 2018:1531958. [PMID: 29623262 PMCID: PMC5830275 DOI: 10.1155/2018/1531958] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Accepted: 11/16/2017] [Indexed: 02/06/2023] Open
Abstract
Functional dyspepsia (FD) is a common functional gastrointestinal disorder with pain or discomfort in the upper abdomen as the main characteristic. The prevalence of FD worldwide varies between 5% and 11%. This condition adversely affects attendance and productivity in the workplace. Emerging evidence is beginning to unravel the pathophysiologies of FD, and new data on treatment are helping to guide evidence-based practice. In order to better understand the pathophysiologies of FD and explore better treatment options, various kinds of animal models of FD have been developed. However, it is unclear which of these models most closely mimic the human disease. This review provides a comprehensive overview of the currently available animal models of FD in relationship to the clinical features of the disease. The rationales, methods, merits, and disadvantages for modelling specific symptoms of FD are discussed in detail.
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11
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Ide S, Yamamoto R, Takeda H, Minami M. Bidirectional brain-gut interactions: Involvement of noradrenergic transmission within the ventral part of the bed nucleus of the stria terminalis. Neuropsychopharmacol Rep 2018; 38:37-43. [PMID: 30106262 PMCID: PMC7292304 DOI: 10.1002/npr2.12004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 11/24/2017] [Accepted: 11/25/2017] [Indexed: 12/16/2022] Open
Abstract
Introduction Although the important roles of bidirectional interactions between the brain and gut in stress and emotional responses have long been recognized, the underlying neuronal mechanisms remain unclear. The bed nucleus of the stria terminalis (BNST) is a limbic structure involved in stress responses and negative affective states, such as anxiety and depression. We have previously demonstrated that noradrenergic transmission within the ventral part of the BNST (vBNST) plays a crucial role in anxiety‐like behaviors and pain‐induced aversion. Objectives This study aimed to examine the involvement of noradrenergic transmission via β‐adrenoceptors within the vBNST in bidirectional brain‐gut interactions. Methods We measured the gastric distention (GD)‐induced noradrenaline release within the vBNST of freely moving rats using an in vivo microdialysis technique. Gastric emptying and intestinal transit were examined following intra‐vBNST injections of isoproterenol, a β‐adrenoceptor agonist, in the absence or presence of the coadministration of timolol, a β‐adrenoceptor antagonist. Results Gastric distention at a higher pressure (45 mm Hg) but not at a lower pressure (25 mm Hg) resulted in a significant increase in extracellular noradrenaline levels within the vBNST. Intra‐vBNST injections of isoproterenol (30 nmol/side) induced significant reductions in gastric emptying and small intestinal transit, both of which were reversed by the coadministration of timolol (30 nmol/side). Conclusion Noradrenergic transmission via β‐adrenoceptors within the vBNST was involved in bidirectional brain‐gut interactions. These findings suggest that gastric dysfunction may induce negative affective states via the enhanced release of noradrenaline within the vBNST which, in turn, may cause gastrointestinal impairments. In vivo microdialysis experiments demonstrated that gastric distention induced an increase in noradrenaline release within the vBNST. Intra‐vBNST injections of isoproterenol, a β‐adrenoceptor agonist, reduced gastric emptying and small intestinal transit, and these reducing effects were reversed by the coadministration of timolol, a β‐adrenoceptor antagonist. The present findings demonstrated important roles of noradrenergic transmission via β‐adrenoceptors within the vBNST in the bidirectional brain‐gut interactions.
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Affiliation(s)
- Soichiro Ide
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan.,Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Ryuta Yamamoto
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Hiroshi Takeda
- Laboratory of Pathophysiology and Therapeutics, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Masabumi Minami
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
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12
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Jing FC, Zhang J, Feng C, Nian YY, Wang JH, Hu H, Yang BD, Sun XM, Zheng JY, Yin XR. Potential rat model of anxiety-like gastric hypersensitivity induced by sequential stress. World J Gastroenterol 2017; 23:7594-7608. [PMID: 29204059 PMCID: PMC5698252 DOI: 10.3748/wjg.v23.i42.7594] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 10/04/2017] [Accepted: 10/18/2017] [Indexed: 02/06/2023] Open
Abstract
AIM To establish a rat model of anxiety-like gastric hypersensitivity (GHS) of functional dyspepsia (FD) induced by novel sequential stress.
METHODS Animal pups were divided into two groups from postnatal day 2: controls and the sequential-stress-treated. The sequential-stress-treated group received maternal separation and acute gastric irritation early in life and restraint stress in adulthood; controls were reared undisturbed with their mothers. Rats in both groups were followed to adulthood (8 wk) at which point the anxiety-like behaviors and visceromotor responses to gastric distention (20-100 mmHg) and gastric emptying were tested. Meanwhile, alterations in several anxiety-related brain-stomach modulators including 5-hydroxytryptamine (5-HT), γ-aminobutyric acid (GABA), brain-derived neurotrophic factor (BDNF) and nesfatin-1 in the rat hippocampus, plasma and gastric fundus and the 5-HT1A receptor (5-HT1AR) in the hippocampal CA1 subfield and the mucosa of the gastric fundus were examined.
RESULTS Sequential-stress-treated rats simultaneously demonstrated anxiety-like behaviors and GHS in dose-dependent manner compared with the control group. Although rats in both groups consumed similar amount of solid food, the rate of gastric emptying was lower in the sequential-stress-treated rats than in the control group. Sequential stress significantly decreased the levels of 5-HT (51.91 ± 1.88 vs 104.21 ± 2.88, P < 0.01), GABA (2.38 ± 0.16 vs 5.01 ± 0.13, P < 0.01) and BDNF (304.40 ± 10.16 vs 698.17 ± 27.91, P < 0.01) in the hippocampus but increased the content of nesfatin-1 (1961.38 ± 56.89 vs 1007.50 ± 33.05, P < 0.01) in the same site; significantly decreased the levels of 5-HT (47.82 ± 2.29 vs 89.45 ± 2.61, P < 0.01) and BDNF (257.05 ± 12.89 vs 536.71 ± 20.73, P < 0.01) in the plasma but increased the content of nesfatin-1 in it (1391.75 ± 42.77 vs 737.88 ± 33.15, P < 0.01); significantly decreased the levels of 5-HT (41.15 ± 1.81 vs 89.17 ± 2.31, P < 0.01) and BDNF (226.49 ± 12.10 vs 551.36 ± 16.47, P < 0.01) in the gastric fundus but increased the content of nesfatin-1 in the same site (1534.75 ± 38.52 vs 819.63 ± 38.04, P < 0.01). The expressions of 5-HT1AR in the hippocampal CA1 subfield and the mucosa of the gastric fundus were down-regulated measured by IHC (Optical Density value: Hippocampus 15253.50 ± 760.35 vs 21149.75 ± 834.13; gastric fundus 15865.25 ± 521.24 vs 23865.75 ± 1868.60; P < 0.05, respectively) and WB (0.38 ± 0.01 vs 0.57 ± 0.03, P < 0.01) (n = 8 in each group).
CONCLUSION Sequential stress could induce a potential rat model of anxiety-like GHS of FD, which could be used to research the mechanisms of this intractable disease.
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Affiliation(s)
- Fu-Chun Jing
- Department of Gastroenterology, Second Hospital Affiliated to the Medical School of Xi’an Jiao Tong University, Xi’an 710004, Shaanxi Province, China
- Department of Digestive Diseases, Baoji People’s Hospital Affiliated to the Medical School of Yan’an University, Baoji 721000, Shaanxi Province, China
| | - Jun Zhang
- Department of Gastroenterology, Second Hospital Affiliated to the Medical School of Xi’an Jiao Tong University, Xi’an 710004, Shaanxi Province, China
| | - Chen Feng
- Department of Gastroenterology, Second Hospital Affiliated to the Medical School of Xi’an Jiao Tong University, Xi’an 710004, Shaanxi Province, China
| | - Yuan-Yuan Nian
- Department of Gastroenterology, Second Hospital Affiliated to the Medical School of Xi’an Jiao Tong University, Xi’an 710004, Shaanxi Province, China
| | - Jin-Hai Wang
- Department of Gastroenterology, Second Hospital Affiliated to the Medical School of Xi’an Jiao Tong University, Xi’an 710004, Shaanxi Province, China
| | - Hao Hu
- Department of Pharmacology, Health Science Center, Xi’an Jiao Tong University, Xi’an 710061, Shaanxi Province, China
- Basic Medical Experiment Teaching Center, Health Science Center, Xi’an Jiao Tong University, Xi’an 710061, Shaanxi Province, China
| | - Bao-De Yang
- Department of Pharmacology, Health Science Center, Xi’an Jiao Tong University, Xi’an 710061, Shaanxi Province, China
- Basic Medical Experiment Teaching Center, Health Science Center, Xi’an Jiao Tong University, Xi’an 710061, Shaanxi Province, China
| | - Xiao-Ming Sun
- Department of Pharmacology, Health Science Center, Xi’an Jiao Tong University, Xi’an 710061, Shaanxi Province, China
- Basic Medical Experiment Teaching Center, Health Science Center, Xi’an Jiao Tong University, Xi’an 710061, Shaanxi Province, China
| | - Jian-Yun Zheng
- Department of Pathology, the First Affiliated Hospital of Xi’an Medical University, Xi’an 710077, Shaanxi Province, China
| | - Xiao-Ran Yin
- Department of Gastroenterology, Second Hospital Affiliated to the Medical School of Xi’an Jiao Tong University, Xi’an 710004, Shaanxi Province, China
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13
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Gao L, Zhao H, Zhu T, Liu Y, Hu L, Liu Z, Huang H, Chen F, Deng Z, Chu D, Du D. The Regulatory Effects of Lateral Hypothalamus Area GABA B Receptor on Gastric Ischemia-Reperfusion Injury in Rats. Front Physiol 2017; 8:722. [PMID: 28983255 PMCID: PMC5613147 DOI: 10.3389/fphys.2017.00722] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 09/06/2017] [Indexed: 12/16/2022] Open
Abstract
HIGHLIGHTSThe aim of the research was to determine the functional effects and molecular mechanisms of GABAB receptor on ischemia reperfusion-induced gastric injury in rats. The lateral hypothalamus area GABAB receptor attenuated the ischemia reperfusion-induced gastric injury by up-regulating the production of GABA, GABABR, and down-regulating P-GABABR in the brain. This work would provide a new therapeutic strategy for acute gastric injury.
Gastric ischemia-reperfusion (GI-R) injury progression is largely associated with excessive activation of the greater splanchnic nerve (GSN). This study aims to investigate the protective effects of GABAB receptor (GABABR) in the lateral hypothalamic area (LHA) on GI-R injury. A model of GI-R injury was established by clamping the celiac artery for 30 min and then reperfusion for 1 h. The coordinate of FN and LHA was identified in Stereotaxic Coordinates and then the L-Glu was microinjected into FN, GABAB receptor agonist baclofen, or GABAB receptor antagonist CGP35348 was microinjected into the LHA, finally the GI-R model was prepared. The expression of GABABR, P-GABABR, NOX2, NOX4, and SOD in the LHA was detected by western blot, PCR, and RT-PCR. The expression of IL-1β, NOX2, and NXO4 in gastric mucosa was detected by western blot. We found that microinjection of L-Glu into the FN or GABAB receptor agonist (baclofen) into the LHA attenuated GI-R injury. Pretreatment with GABAB receptor antagonist CGP35348 reversed the protective effects of FN stimulation or baclofen into the LHA. Microinjection of baclofen into the LHA obviously reduced the expression of inflammatory factor IL-1β, NOX2, and NOX4 in the gastric mucosa. Conclusion: The protective effects of microinjection of GABABR agonist into LHA on GI-R injury in rats could be mediated by up-regulating the production of GABA, GABABR, and down-regulating P-GABABR in the LHA.
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Affiliation(s)
- Lin Gao
- Neurology Center, The First Affiliated Hospital of Zhengzhou UniversityZhengzhou, China
| | - Huiru Zhao
- Shanghai Key Laboratory of Bio-Crops, College of Life Science, Shanghai UniversityShanghai, China
| | - Tao Zhu
- Department of Life Science, Heze UniversityHeze, China
| | - Yeliu Liu
- Department of General Surgery, Huai'an First People's Hospital, Nanjing Medical UniversityHuai'an, China
| | - Li Hu
- Shanghai Key Laboratory of Bio-Crops, College of Life Science, Shanghai UniversityShanghai, China
| | - Zhenguo Liu
- Shanghai Key Laboratory of Bio-Crops, College of Life Science, Shanghai UniversityShanghai, China
| | - Hai Huang
- Shanghai Key Laboratory of Bio-Crops, College of Life Science, Shanghai UniversityShanghai, China
| | - Fuxue Chen
- Shanghai Key Laboratory of Bio-Crops, College of Life Science, Shanghai UniversityShanghai, China
| | - Zhenxu Deng
- Department of Life Science, Heze UniversityHeze, China
| | - Dechang Chu
- Department of Life Science, Heze UniversityHeze, China
| | - Dongshu Du
- Neurology Center, The First Affiliated Hospital of Zhengzhou UniversityZhengzhou, China.,Shanghai Key Laboratory of Bio-Crops, College of Life Science, Shanghai UniversityShanghai, China
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14
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Li M, Xue L, Zhu HY, Wang H, Xu X, Zhang PA, Wu G, Xu GY. Protein Kinase C Mediates the Corticosterone-induced Sensitization of Dorsal Root Ganglion Neurons Innervating the Rat Stomach. J Neurogastroenterol Motil 2017; 23:464-476. [PMID: 28343377 PMCID: PMC5503297 DOI: 10.5056/jnm16161] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 12/31/2016] [Accepted: 01/15/2017] [Indexed: 12/13/2022] Open
Abstract
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.
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Affiliation(s)
| | | | | | | | | | | | | | - Guang-Yin Xu
- Correspondence: Guang-Yin Xu, MD, PhD, Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases, Institute of Neuroscience, Soochow University, 199 Ren-Ai Road, Suzhou 215123, China, Tel: +86-512-6588-2817, Fax: +86-512-6588-3602, E-mail:
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15
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Zhou J, Li S, Wang Y, Foreman RD, Yin J, Zhang S, Chen JDZ. Inhibitory Effects and Mechanisms of Electroacupuncture via Chronically Implanted Electrodes on Stress-Induced Gastric Hypersensitivity in Rats With Neonatal Treatment of Iodoacetamide. Neuromodulation 2017; 20:767-773. [PMID: 28393479 DOI: 10.1111/ner.12602] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 01/18/2017] [Accepted: 02/15/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND Stress is considered an independent factor causing and aggravating gastrointestinal symptoms, including visceral pain. The aim of this study was to investigate effects and mechanisms of electroacupuncture (EA) on stress-induced gastric hypersensitivity in rats treated with neonatal iodoacetamide mimicking human functional dyspepsia (FD). METHODS Neonatal rats were treated with gavage of 0.2 mL of 0.1% iodoacetamide in 2% sucrose daily for six days starting on tenth day after birth. The control group was given 0.2 mL of 2% sucrose. When the rats were eight weeks old, acute restraint stress was performed on them for 90 min. EA at ST36 (ZuSanLi) was performed during the acute stress or 30 min after the stress. Adrenoceptor blocking drugs (propranolol and phentolamine) were injected intraperitoneally 30 min before acute restraint stress to explore possible sympathetic mechanisms. Visceral-motor responses to gastric distention were assessed by electromyogram (EMG). RESULTS 1) Stress-induced gastric hypersensitivity was significantly more severe in the FD rats, compared to the control rats. It was blocked by the adrenoceptor antagonists. 2) EA inhibited stress-induced gastric hypersensitivity; the preventive effect of EA (given during stress) was more remarkable than the curative effect (given after stress). Stress resulted in a higher sympathovagal ratio and this was suppressed by EA. CONCLUSIONS Rats treated with neonatal iodoacetamide mimicking FD are more vulnerable to stress. Stress-induced gastric hypersensitivity can be prevented or suppressed by EA at ST36 via the restoration of sympathovagal balance.
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Affiliation(s)
- Jingzhu Zhou
- Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, OK, USA.,Department of Physiology, University of Oklahoma Health Science Center, Oklahoma City, OK, USA.,Department of Acupuncture and Moxibustion, The First Affiliated Hospital with Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Shiying Li
- Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, OK, USA
| | - Yinping Wang
- Department of Acupuncture and Moxibustion, The First Affiliated Hospital with Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Robert D Foreman
- Department of Physiology, University of Oklahoma Health Science Center, Oklahoma City, OK, USA
| | - Jieyun Yin
- Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, OK, USA
| | - Shengsheng Zhang
- Digestive Disease Center, Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, Beijing, China
| | - Jiande D Z Chen
- Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, OK, USA.,Center of Neurogastroenterology, Johns Hopkins Medicine, Baltimore, MD, USA
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16
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Singh M, Malik P, Bhushan R. Resolution of Enantiomers of (RS)-Baclofen by Ligand-Exchange Thin-Layer Chromatography. J Chromatogr Sci 2016; 54:842-6. [PMID: 26896346 DOI: 10.1093/chromsci/bmw014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Indexed: 11/14/2022]
Abstract
A new chromatographic method has been developed for direct enantioresolution of (RS)-baclofen by ligand-exchange thin-layer chromatography (TLC) adopting two different approaches; (A) TLC plates were prepared by mixing the ligand exchange reagents (LER) with silica gel slurry and the chromatograms were developed with different achiral solvents or solvents having no chiral additive, and (B) the LER consisting of Cu(II)-L-amino acid complex was used as chiral mobile phase additive and the plain plates of silica gel having no chiral selector were used. Cu(II) acetate and four L-amino acids (namely, L-tryptophan, L-histidine, L-proline and L-phenylalanine) were used for the preparation of LERs. Spots were located by the use of iodine vapor. Effect of temperature and the mole ratio of Cu(II)-to-amino acid on enantioresolution were also studied. The results for the two methods have been compared, and the issue of involvement of the Cu(II) cation for the best performance of the two methods has been discussed with respect to the same mobile phase. L-Trp proved to be a good ligand using a common mobile phase in each case.
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Affiliation(s)
- Manisha Singh
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Poonam Malik
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Ravi Bhushan
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, India
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17
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Johnson AC, Greenwood-Van Meerveld B. The Pharmacology of Visceral Pain. ADVANCES IN PHARMACOLOGY 2016; 75:273-301. [PMID: 26920016 DOI: 10.1016/bs.apha.2015.11.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Visceral pain describes pain emanating from the internal thoracic, pelvic, or abdominal organs. Unlike somatic pain, visceral pain is generally vague, poorly localized, and characterized by hypersensitivity to a stimulus such as organ distension. While current therapeutics provides some relief from somatic pain, drugs used for treatment of chronic visceral pain are typically less efficacious and limited by multiple adverse side effects. Thus, the treatment of visceral pain represents a major unmet medical need. Further, more basic research into the physiology and pathophysiology of visceral pain is needed to provide novel targets for future drug development. In concert with chronic visceral pain, there is a high comorbidity with stress-related psychiatric disorders including anxiety and depression. The mechanisms linking visceral pain with these overlapping comorbidities remain to be elucidated. However, persistent stress facilitates pain perception and sensitizes pain pathways, leading to a feed-forward cycle promoting chronic visceral pain disorders. We will focus on stress-induced exacerbation of chronic visceral pain and provide supporting evidence that centrally acting drugs targeting the pain and stress-responsive brain regions may represent a valid target for the development of novel and effective therapeutics.
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Affiliation(s)
- Anthony C Johnson
- Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Beverley Greenwood-Van Meerveld
- Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA; Veterans Affairs Medical Center, Oklahoma City, Oklahoma, USA; Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.
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18
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Altered Ion Channel/Receptor Expression and Function in Extrinsic Sensory Neurons: The Cause of and Solution to Chronic Visceral Pain? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 891:75-90. [PMID: 27379637 DOI: 10.1007/978-3-319-27592-5_9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The gastrointestinal tract is unique in that it is innervated by several distinct populations of neurons, whose cell bodies are either intrinsic (enteric, viscerofugal) or extrinsic (sympathetic, sensory afferents) to the wall of the gut. We are usually completely unaware of the continuous, complicated orchestra of functions that these neurons conduct. However, for patients with Inflammatory Bowel Disease (IBD) or functional gastrointestinal disorders, such as Functional Dyspepsia (FD) and Irritable Bowel Syndrome (IBS) altered gastrointestinal motility, discomfort and pain are common, debilitating symptoms. Whilst bouts of inflammation underlie the symptoms associated with IBD, over the past few years there is increased pre-clinical and clinical evidence that infection and inflammation are key risk factors for the development of several functional gastrointestinal disorders, in particular IBS. There is a strong correlation between prior exposure to gut infection and symptom occurrence; with the duration and severity of the initial illness the strongest associated risk factors. This review discusses the current body of evidence for neuroplasticity during inflammation and how in many cases fails to reset back to normal, long after healing of the damaged tissues. Recent evidence suggests that the altered expression and function of key ion channels and receptors within extrinsic sensory neurons play fundamental roles in the aberrant pain sensation associated with these gastrointestinal diseases and disorders.
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19
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Liu J, Li F, Tang XD, Ma J, Ma X, Ge DY, Li GM, Wang Y. XiangshaLiujunzi decoction alleviates the symptoms of functional dyspepsia by regulating brain-gut axis and production of neuropeptides. Altern Ther Health Med 2015; 15:387. [PMID: 26508134 PMCID: PMC4623916 DOI: 10.1186/s12906-015-0913-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 10/13/2015] [Indexed: 12/15/2022]
Abstract
Background Chinese medicine xiangshaliujunzi decoction (XSLJZD) plays a key role in treating functional dyspepsia (FD), a common clinical gastrointestinal disorder. However, the mechanism of this disease is unclear. Brain–gut axis regulates food intake behaviour, and this regulatory mechanism is mediated by neuropeptides. Brain–gut axis impairment and neuropeptide alteration may be the pathological mechanisms of FD, and brain–gut axis regulation may influence the action of medicine. Methods In our experiment, the effect of XSLJZD on FD was evaluated in terms of food intake, sucrose preference test and electromyogram. Changes in neuropeptides [ghrelin, cholecystokinin (CCK) and vasoactive intestinal polypeptide (VIP)] were detected through immunohistochemistry, real-time PCR and ELISA. Results XSLJZD increased food intake and the percentage of sucrose preference (>75 %). However, the response to gastric detention decreased. Furthermore, XSLJZD increased ghrelin, CCK, VIP proteins and genes in the stomach. XSLJZD also increased ghrelin, CCK and VIP proteins in serum. By contrast, XSLJZD decreased the mRNA expression of these neuropeptides in the hypothalamus. Conclusions XSLJZD alleviated the symptoms of FD by upregulating the production of ghrelin, CCK and VIP and by increasing the levels of these neuropeptides in circulation. This finding can help elucidate the mechanism of FD and can provide further insight into the pharmacokinetics of XSLJZD.
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20
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Greenwood-Van Meerveld B, Prusator DK, Johnson AC. Animal models of gastrointestinal and liver diseases. Animal models of visceral pain: pathophysiology, translational relevance, and challenges. Am J Physiol Gastrointest Liver Physiol 2015; 308:G885-903. [PMID: 25767262 DOI: 10.1152/ajpgi.00463.2014] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 03/11/2015] [Indexed: 02/08/2023]
Abstract
Visceral pain describes pain emanating from the thoracic, pelvic, or abdominal organs. In contrast to somatic pain, visceral pain is generally vague, poorly localized, and characterized by hypersensitivity to a stimulus such as organ distension. Animal models have played a pivotal role in our understanding of the mechanisms underlying the pathophysiology of visceral pain. This review focuses on animal models of visceral pain and their translational relevance. In addition, the challenges of using animal models to develop novel therapeutic approaches to treat visceral pain will be discussed.
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Affiliation(s)
- Beverley Greenwood-Van Meerveld
- Veterans Affairs Medical Center, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; and Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Dawn K Prusator
- Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Anthony C Johnson
- Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
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21
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Moloney RD, O'Mahony SM, Dinan TG, Cryan JF. Stress-induced visceral pain: toward animal models of irritable-bowel syndrome and associated comorbidities. Front Psychiatry 2015; 6:15. [PMID: 25762939 PMCID: PMC4329736 DOI: 10.3389/fpsyt.2015.00015] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/28/2015] [Indexed: 12/12/2022] Open
Abstract
Visceral pain is a global term used to describe pain originating from the internal organs, which is distinct from somatic pain. It is a hallmark of functional gastrointestinal disorders such as irritable-bowel syndrome (IBS). Currently, the treatment strategies targeting visceral pain are unsatisfactory, with development of novel therapeutics hindered by a lack of detailed knowledge of the underlying mechanisms. Stress has long been implicated in the pathophysiology of visceral pain in both preclinical and clinical studies. Here, we discuss the complex etiology of visceral pain reviewing our current understanding in the context of the role of stress, gender, gut microbiota alterations, and immune functioning. Furthermore, we review the role of glutamate, GABA, and epigenetic mechanisms as possible therapeutic strategies for the treatment of visceral pain for which there is an unmet medical need. Moreover, we discuss the most widely described rodent models used to model visceral pain in the preclinical setting. The theory behind, and application of, animal models is key for both the understanding of underlying mechanisms and design of future therapeutic interventions. Taken together, it is apparent that stress-induced visceral pain and its psychiatric comorbidities, as typified by IBS, has a multifaceted etiology. Moreover, treatment strategies still lag far behind when compared to other pain modalities. The development of novel, effective, and specific therapeutics for the treatment of visceral pain has never been more pertinent.
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Affiliation(s)
- Rachel D Moloney
- Laboratory of Neurogastroenterology, Alimentary Pharmabiotic Centre, Biosciences Institute, University College Cork , Cork , Ireland
| | - Siobhain M O'Mahony
- Laboratory of Neurogastroenterology, Alimentary Pharmabiotic Centre, Biosciences Institute, University College Cork , Cork , Ireland ; Department of Anatomy and Neuroscience, University College Cork , Cork , Ireland
| | - Timothy G Dinan
- Laboratory of Neurogastroenterology, Alimentary Pharmabiotic Centre, Biosciences Institute, University College Cork , Cork , Ireland ; Department of Psychiatry, University College Cork , Cork , Ireland
| | - John F Cryan
- Laboratory of Neurogastroenterology, Alimentary Pharmabiotic Centre, Biosciences Institute, University College Cork , Cork , Ireland ; Department of Anatomy and Neuroscience, University College Cork , Cork , Ireland
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Abstract
The gastrointestinal tract is innervated by several distinct populations of neurons, whose cell bodies either reside within (intrinsic) or outside (extrinsic) the gastrointestinal wall. Normally, most individuals are unaware of the continuous, complicated functions of these neurons. However, for patients with gastrointestinal disorders, such as IBD and IBS, altered gastrointestinal motility, discomfort and pain are common, debilitating symptoms. Although bouts of intestinal inflammation underlie the symptoms associated with IBD, increasing preclinical and clinical evidence indicates that infection and inflammation are also key risk factors for the development of other gastrointestinal disorders. Notably, a strong correlation exists between prior exposure to gut infection and symptom occurrence in IBS. This Review discusses the evidence for neuroplasticity (structural, synaptic or intrinsic changes that alter neuronal function) affecting gastrointestinal function. Such changes are evident during inflammation and, in many cases, long after healing of the damaged tissues, when the nervous system fails to reset back to normal. Neuroplasticity within distinct populations of neurons has a fundamental role in the aberrant motility, secretion and sensation associated with common clinical gastrointestinal disorders. To find appropriate therapeutic treatments for these disorders, the extent and time course of neuroplasticity must be fully appreciated.
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23
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Li S, Chen JDZ. Down-regulation of A-type potassium channel in gastric-specific DRG neurons in a rat model of functional dyspepsia. Neurogastroenterol Motil 2014; 26:962-70. [PMID: 24758381 DOI: 10.1111/nmo.12350] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Accepted: 03/28/2014] [Indexed: 02/08/2023]
Abstract
BACKGROUND Although without evidence of organic structural abnormalities, pain or discomfort is a prominent symptom of functional dyspepsia and considered to reflect visceral hypersensitivity whose underlying mechanism is poorly understood. Here, we studied electrophysiological properties and expression of voltage-gated potassium channels in dorsal root ganglion (DRG) neurons in a rat model of functional dyspepsia induced by neonatal gastric irritation. METHODS Male Sprague-Dawley rat pups at 10-day old received 0.1% iodoacetamide (IA) or vehicle by oral gavage for 6 days and studied at adulthood. Retrograde tracer-labeled gastric-specific T8 -T12 DRG neurons were harvested for the patch-clamp study in voltage and current-clamp modes and protein expression of K(+) channel in T8 -T12 DRGs was examined by western blotting. KEY RESULTS (1) Gastric specific but not non-gastric DRG neurons showed an enhanced excitability in neonatal IA-treated rats compared to the control: depolarized resting membrane potentials, a lower current threshold for action potential (AP) activation, and an increase in the number of APs in response to current stimulation. (2) The current density of tetraethylammonium insensitive (transiently inactivating A-type current), but not the tetraethylammonium sensitive (slow-inactivating delayed rectifier K(+) currents), was significantly smaller in IA-treated rats (65.4 ± 6.9 pA/pF), compared to that of control (93.1 ± 8.3 pA/pF). (3) Protein expression of KV 4.3 was down-regulated in IA-treated rats. CONCLUSIONS & INFERENCES A-type potassium channels are significantly down-regulated in the gastric-specific DRG neurons in adult rats with mild neonatal gastric irritation, which in part contribute to the enhanced DRG neuron excitabilities that leads to the development of gastric hypersensitivity.
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Affiliation(s)
- S Li
- Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, OK, USA
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Zhang HH, Hu J, Zhou YL, Hu S, Wang YM, Chen W, Xiao Y, Huang LYM, Jiang X, Xu GY. Promoted interaction of nuclear factor-κB with demethylated cystathionine-β-synthetase gene contributes to gastric hypersensitivity in diabetic rats. J Neurosci 2013; 33:9028-38. [PMID: 23699514 PMCID: PMC6705038 DOI: 10.1523/jneurosci.1068-13.2013] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 04/11/2013] [Accepted: 04/16/2013] [Indexed: 12/13/2022] Open
Abstract
Patients with long-standing diabetes frequently demonstrate gastric hypersensitivity with an unknown mechanism. The present study was designed to investigate roles for nuclear factor-κB (NF-κB) and the endogenous H2S-producing enzyme cystathionine-β-synthetase (CBS) signaling pathways by examining cbs gene methylation status in adult rats with diabetes. Intraperitoneal injection of streptozotocin (STZ) produced gastric hypersensitivity in female rats in response to gastric balloon distention. Treatment with the CBS inhibitor aminooxyacetic acid significantly attenuated STZ-induced gastric hypersensitivity in a dose-dependent fashion. Aminooxyacetic acid treatment also reversed hyperexcitability of gastric-specific dorsal root ganglion (DRG) neurons labeled by the dye DiI in diabetic rats. Conversely, the H2S donor NaHS enhanced neuronal excitability of gastric DRG neurons. Expression of CBS and p65 were markedly enhanced in gastric DRGs in diabetic rats. Blockade of NF-κB signaling using pyrrolidine dithiocarbamate reversed the upregulation of CBS expression. Interestingly, STZ treatment led to a significant demethylation of CpG islands in the cbs gene promoter region, as determined by methylation-specific PCR and bisulfite sequencing. STZ treatment also remarkably downregulated the expression of DNA methyltransferase 3a and 3b. More importantly, STZ treatment significantly enhanced the ability of cbs to bind DNA at the p65 consensus site, as shown by chromatin immunoprecipitation assays. Our findings suggest that upregulation of cbs expression is attributed to cbs promoter DNA demethylation and p65 activation and that the enhanced interaction of the cbs gene and p65 contributes to gastric hypersensitivity in diabetes. This finding may guide the development and evaluation of new treatment modalities for patients with diabetic gastric hypersensitivity.
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Affiliation(s)
- Hong-Hong Zhang
- Division of Endocrinology, the Second Affiliated Hospital, Soochow University, Suzhou 215000, P.R. China
- Institute of Neuroscience, Suzhou Key Laboratory of Pain Research and Therapy, Department of Neurobiology, Soochow University, Suzhou 215123, P.R. China
| | - Ji Hu
- Division of Endocrinology, the Second Affiliated Hospital, Soochow University, Suzhou 215000, P.R. China
| | - You-Lang Zhou
- Institute of Neuroscience, Suzhou Key Laboratory of Pain Research and Therapy, Department of Neurobiology, Soochow University, Suzhou 215123, P.R. China
- Hand Surgery Research Center, Department of Hand Surgery, Affiliated Hospital of Nantong University, Nantong 226001, P.R. China, and
| | - Shufen Hu
- Institute of Neuroscience, Suzhou Key Laboratory of Pain Research and Therapy, Department of Neurobiology, Soochow University, Suzhou 215123, P.R. China
| | - Yong-Meng Wang
- Institute of Neuroscience, Suzhou Key Laboratory of Pain Research and Therapy, Department of Neurobiology, Soochow University, Suzhou 215123, P.R. China
| | - Wei Chen
- Hand Surgery Research Center, Department of Hand Surgery, Affiliated Hospital of Nantong University, Nantong 226001, P.R. China, and
| | - Ying Xiao
- Division of Endocrinology, the Second Affiliated Hospital, Soochow University, Suzhou 215000, P.R. China
| | - Li-Yen Mae Huang
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas 77555-1069
| | - Xinghong Jiang
- Institute of Neuroscience, Suzhou Key Laboratory of Pain Research and Therapy, Department of Neurobiology, Soochow University, Suzhou 215123, P.R. China
| | - Guang-Yin Xu
- Division of Endocrinology, the Second Affiliated Hospital, Soochow University, Suzhou 215000, P.R. China
- Institute of Neuroscience, Suzhou Key Laboratory of Pain Research and Therapy, Department of Neurobiology, Soochow University, Suzhou 215123, P.R. China
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Lee S, Zhao X, Hatch M, Chun S, Chang E. Central Neuropathic Pain in Spinal Cord Injury. ACTA ACUST UNITED AC 2013; 25:159-172. [PMID: 25750485 DOI: 10.1615/critrevphysrehabilmed.2013007944] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Spinal cord injury (SCI) is a devastating medical condition affecting 1.2 million people in the United States. Central neuropathic pain is one of the most common medical complications of SCI. Current treatment options include opioids, antiepileptic agents such as gabapentin, antispastic agents such as baclofen or tizanidine, and tricyclic acid. Other options include complementary, nonpharmacological treatment such as exercise or acupuncture, interventional treatments, and psychological approaches. Although these treatment options exist, central neuropathic pain in patients with SCI is still extremely difficult to treat because of its complexity. To develop and provide more effective treatment options to these patients, proper assessment of and classification tools for central neuropathic pain, as well as a better understanding of the pathophysiology, are needed. A combination of approaches, from standard general pain assessments to medically specific questions unique to SCI pathophysiology, is essential for this population. A multidisciplinary approach to patient care, in addition with a better understanding of pathophysiology and diagnosis, will lead to improved management and treatment of patients with SCI displaying central neuropathic pain. Here we summarize the most recent classification tools, pathophysiology, and current treatment options for patients with SCI with central neuropathic pain.
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Affiliation(s)
- Sujin Lee
- Department of Physical Medicine and Rehabilitation, University of California, Irvine, CA
| | - Xing Zhao
- Department of Physical Medicine and Rehabilitation, University of California, Irvine, CA
| | - Maya Hatch
- Reeve-Irvine Research Center, University of California, Irvine, CA
| | - Sophia Chun
- Spinal Cord Injury Medicine/Disease, Long Beach VA Hospital, Long Beach, CA
| | - Eric Chang
- Department of Physical Medicine and Rehabilitation, University of California, Irvine, CA
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Suliman FO, Elbashir AA. Enantiodifferentiation of chiral baclofen by β-cyclodextrin using capillary electrophoresis: A molecular modeling approach. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.03.055] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Refractory gastroesophageal reflux disease may affect up to one-third of the patients that consume proton pump inhibitor (PPI) once daily. Treatment in clinical practice has been primarily focused on doubling the PPI dose, despite lack of evidence of its value. In patients who failed PPI twice daily, medical treatment has been primarily focused on reducing transient lower esophageal sphincter relaxation rate or attenuating esophageal pain perception using visceral analgesics. In patients with evidence of reflux as the direct trigger of their symptoms, endoscopic treatment or antireflux surgery may be helpful in remitting symptoms. The role of psychological interventions, as well as non-traditional therapeutic strategies remains to be further elucidated.
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Affiliation(s)
- Ronnie Fass
- The Neuroenteric Clinical Research Group, Southern Arizona VA Health Care System, University of Arizona, Tucson, Arizona 85723-0001, USA.
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Moloney RD, O'Leary OF, Felice D, Bettler B, Dinan TG, Cryan JF. Early-life stress induces visceral hypersensitivity in mice. Neurosci Lett 2012; 512:99-102. [PMID: 22326388 DOI: 10.1016/j.neulet.2012.01.066] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Revised: 01/26/2012] [Accepted: 01/27/2012] [Indexed: 12/23/2022]
Abstract
Early-life stress is a risk factor for irritable bowel syndrome (IBS), a common and debilitating functional gastrointestinal disorder that is often co-morbid with stress-related psychiatric disorders. In the rat, maternal separation (MS) stress has been shown to induce visceral hypersensitivity in adulthood and thus has become a useful model of IBS. However, development of mouse models of maternal separation has been difficult. Given the advent of transgenic mouse technology, such models would be useful to further our understanding of the pathophysiology of IBS and to develop new pharmacological treatments. Thus, the present study aimed to develop a mouse model of MS stress-induced visceral hyperalgesia as measured using manometric recordings of colorectal distension (CRD). Moreover, since the GABA(B) receptor has been reported to play a role in pain processes, we also assessed its role in visceral nociception using novel GABA(B(1b)) receptor subunit knockout mice. CRD was performed in adult male wildtype and GABA(B(1b)) receptor knockout mice that had undergone unpredictable MS combined with unpredictable maternal stress (MSUS) from postnatal day 1 through 14 (PND 1-14). MSUS induced visceral hypersensitivity in both wildtype and GABA(B(1b)) receptor knockout mice when compared with non-stressed mice. Wildtype and GABA(B(1b)) receptor knockout mice did not differ in baseline or stress-induced visceral sensitivity. To the best of our knowledge, this is the first study to show that early-life stress induces visceral hypersensitivity in a mouse model. These findings may provide a novel mouse model of visceral hypersensitivity which may aid our understanding of its underlying mechanisms in future studies.
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Affiliation(s)
- Rachel D Moloney
- Laboratory of Neurogastroenterology, Alimentary Pharmabiotic Centre, Biosciences Institute, University College Cork, Ireland
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Current World Literature. Curr Opin Support Palliat Care 2012; 6:109-25. [DOI: 10.1097/spc.0b013e328350f70c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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