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Wang R, Zhou K, Xiong R, Yang Y, Yi R, Hu J, Liao W, Zhao X. Pretreatment with Lactobacillus fermentum XY18 Relieves Gastric Injury Induced by HCl/Ethanol in Mice via Antioxidant and Anti-Inflammatory Mechanisms. DRUG DESIGN DEVELOPMENT AND THERAPY 2021; 14:5721-5734. [PMID: 33408461 PMCID: PMC7779313 DOI: 10.2147/dddt.s280429] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 12/12/2020] [Indexed: 12/11/2022]
Abstract
Aim Lactobacillus fermentum XY18 (LF-XY18) is a bacterial strain with satisfactory antioxidant properties in vitro that we previously isolated from Xinjiang yogurt. This article will explore the preventive effect of LF-XY18 on acute gastric injury and provide the basis for the innovative development and application of lactic acid bacteria (LAB). Methods Kunming mice underwent gastric injury induced by hydrochloric acid and ethanol. LF-XY18 isolated from yogurt in Xinyuan County in the Yili region of Xinjiang was subsequently administered intragastrically to mice for 2 weeks to explore the mechanism of LF-XY18 in preventing gastric injury via its antioxidant effects. Results There was decreased gastric juice volume, gastric injury area, and formation of gastric mucosal lesions in the LF-XY18 mice as compared to those in the control mice, while LF-XY18 prevented the decrease in the gastric juice pH value in mice. Compared with the gastric injury model group mice, LF-XY18 reduced the serum levels of motilin, substance P, interleukin-6, interleukin-12, tumor necrosis factor-α, and interferon-γ but increased the serum levels of somatostatin and vasoactive intestinal peptide. The activities of superoxide dismutase, glutathione peroxidase, glutathione, and nitric oxide were increased in the gastric tissue of the LF-XY18 mice compared with the control mice, but malondialdehyde activity was decreased in the LF-XY18 mice. Quantitative polymerase chain reaction analysis illustrated that in the gastric tissue of LF-XY18 mice, the messenger RNA (mRNA) expression of occludin, epidermal growth factor (EGF), EGF receptor, vascular EGF, inhibitor kappa-B-α, neuronal nitric oxide synthase, endothelial nitric oxide synthase, cuprozinc superoxide dismutase, manganese superoxide dismutase, and catalase was stronger than that in the control mice, but the mRNA expression of activated B cells (NF-κB), inducible nitric oxide synthase, and cyclooxygenase-2 was weaker than in the control mice. Conclusion These results indicate that LF-XY18 has a potential role in the prevention of gastric injury through antioxidant effects, and a high concentration (1.0 × 109 CFU/kg b.w.) of LF-XY18 has a stronger anti-gastric injury effect than a low concentration (1.0 × 108 CFU/kg b.w.).
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Affiliation(s)
- Ranran Wang
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Research Center of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Laboratory for Research and Development of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,College of Biological and Chemical Engineering, Chongqing University of Education, Chongqing, People's Republic of China
| | - Kexiang Zhou
- Gastroenterology, The Third Affiliated Hospital, Chongqing Medical University, Chongqing, People's Republic of China
| | - Rongrong Xiong
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Research Center of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Laboratory for Research and Development of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,College of Biological and Chemical Engineering, Chongqing University of Education, Chongqing, People's Republic of China
| | - Yi Yang
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Research Center of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Laboratory for Research and Development of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,College of Biological and Chemical Engineering, Chongqing University of Education, Chongqing, People's Republic of China
| | - Ruokun Yi
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Research Center of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Laboratory for Research and Development of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China
| | - Jing Hu
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Research Center of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Laboratory for Research and Development of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,College of Biological and Chemical Engineering, Chongqing University of Education, Chongqing, People's Republic of China
| | - Wei Liao
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Department of Public Health, Our Lady of Fatima University, Valenzuela, Philippines
| | - Xin Zhao
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Research Center of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China.,Chongqing Engineering Laboratory for Research and Development of Functional Food, Chongqing University of Education, Chongqing, People's Republic of China
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Guo H, Chen B, Yan Z, Gao J, Tang J, Zhou C. Metabolites profiling and pharmacokinetics of troxipide and its pharmacodynamics in rats with gastric ulcer. Sci Rep 2020; 10:13619. [PMID: 32788674 PMCID: PMC7423950 DOI: 10.1038/s41598-020-70312-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 07/24/2020] [Indexed: 12/17/2022] Open
Abstract
Troxipide is widely used to treat gastric ulcer (GU) in the clinic. However, a lack of systematic metabolic, pharmacokinetic and pharmacological studies limits its clinical use. This study aimed to firstly explore the metabolic, pharmacokinetic and pharmacological mechanisms of troxipide in rats with GU compared to normal control (NC) rats. First, metabolic study was perormed by a highly selective, high-resolution mass spectrometry method. A total of 45 metabolites, including 9 phase I metabolites and 36 phase II metabolites, were identified based on MS/MS spectra. Subsequently, the pharmacokinetics results suggested that the Cmax, Ka, t1/2, AUC(0-t) and AUC(0-∞) of troxipide were significantly increased in rats with GU compared with NC rats. The Vz, K10 and absolute bioavailability of troxipide were obviously decreased in rats with GU compared with NC rats, and its tissue distribution (in the liver, lung and kidney) was significantly different between the two groups of rats. Additionally, the pharmacodynamic results suggested that the levels of biochemical factors (IL-17, IL-6, TNF-α, IFN-γ, AP-1, MTL, GAS, and PG-II) were significantly increased, the PG-Ӏ level was obviously decreased, and the protein expression levels of HSP-90, C-Cas-3 and C-PARP-1 were markedly increased in rats with GU compared with NC rats. The above results suggested that the therapeutic mechanisms underlying the metabolic, pharmacokinetic and pharmacological properties of troxipide in vivo in rats deserve further attention based on the importance of troxipide in the treatment of GU in this study, and these mechanisms could be targets for future studies.
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Affiliation(s)
- Hongbin Guo
- College of Pharmaceutical Sciences, Institute of Life Science and Green Development, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, 180 WuSi Road, Lianchi District, Baoding, 071002, China
| | - Baohua Chen
- College of Pharmaceutical Sciences, Institute of Life Science and Green Development, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, 180 WuSi Road, Lianchi District, Baoding, 071002, China
| | - Zihan Yan
- College of Pharmaceutical Sciences, Institute of Life Science and Green Development, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, 180 WuSi Road, Lianchi District, Baoding, 071002, China
| | - Jian Gao
- College of Pharmaceutical Sciences, Institute of Life Science and Green Development, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, 180 WuSi Road, Lianchi District, Baoding, 071002, China
| | - Jiamei Tang
- College of Pharmaceutical Sciences, Institute of Life Science and Green Development, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, 180 WuSi Road, Lianchi District, Baoding, 071002, China
| | - Chengyan Zhou
- College of Pharmaceutical Sciences, Institute of Life Science and Green Development, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, 180 WuSi Road, Lianchi District, Baoding, 071002, China.
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Suo H, Feng X, Zhu K, Wang C, Zhao X, Kan J. Shuidouchi (Fermented Soybean) Fermented in Different Vessels Attenuates HCl/Ethanol-Induced Gastric Mucosal Injury. Molecules 2015; 20:19748-63. [PMID: 26540032 PMCID: PMC6332132 DOI: 10.3390/molecules201119654] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 10/20/2015] [Indexed: 12/27/2022] Open
Abstract
Shuidouchi (Natto) is a fermented soy product showing in vivo gastric injury preventive effects. The treatment effects of Shuidouchi fermented in different vessels on HCl/ethanol-induced gastric mucosal injury mice through their antioxidant effect was determined. Shuidouchi contained isoflavones (daidzein and genistein), and GVFS (glass vessel fermented Shuidouchi) had the highest isoflavone levels among Shuidouchi samples fermented in different vessels. After treatment with GVFS, the gastric mucosal injury was reduced as compared to the control mice. The gastric secretion volume (0.47 mL) and pH of gastric juice (3.1) of GVFS treated gastric mucosal injury mice were close to those of ranitidine-treated mice and normal mice. Shuidouchi could decrease serum motilin (MTL), gastrin (Gas) level and increase somatostatin (SS), vasoactive intestinal peptide (VIP) level, and GVFS showed the strongest effects. GVFS showed lower IL-6, IL-12, TNF-α and IFN-γ cytokine levels than other vessel fermented Shuidouchi samples, and these levels were higher than those of ranitidine-treated mice and normal mice. GVFS also had higher superoxide dismutase (SOD), nitric oxide (NO) and malonaldehyde (MDA) contents in gastric tissues than other Shuidouchi samples. Shuidouchi could raise IκB-α, EGF, EGFR, nNOS, eNOS, Mn-SOD, Gu/Zn-SOD, CAT mRNA expressions and reduce NF-κB, COX-2, iNOS expressions as compared to the control mice. GVFS showed the best treatment effects for gastric mucosal injuries, suggesting that glass vessels could be used for Shuidouchi fermentation in functional food manufacturing.
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Affiliation(s)
- Huayi Suo
- College of Food Science, Southwest University, Chongqing 400715, China.
- Chongqing Engineering Research Center of Regional Food, Chongqing 400715, China.
| | - Xia Feng
- Department of Biological and Chemical Engineering, Chongqing University of Education, Chongqing 400067, China.
- Chongqing Collaborative Innovation Center of Functional Food, Chongqing University of Education, Chongqing 400067, China.
| | - Kai Zhu
- Department of Biological and Chemical Engineering, Chongqing University of Education, Chongqing 400067, China.
- Chongqing Collaborative Innovation Center of Functional Food, Chongqing University of Education, Chongqing 400067, China.
| | - Cun Wang
- Department of Biological and Chemical Engineering, Chongqing University of Education, Chongqing 400067, China.
- Chongqing Collaborative Innovation Center of Functional Food, Chongqing University of Education, Chongqing 400067, China.
| | - Xin Zhao
- Department of Biological and Chemical Engineering, Chongqing University of Education, Chongqing 400067, China.
- Chongqing Collaborative Innovation Center of Functional Food, Chongqing University of Education, Chongqing 400067, China.
| | - Jianquan Kan
- College of Food Science, Southwest University, Chongqing 400715, China.
- Chongqing Engineering Research Center of Regional Food, Chongqing 400715, China.
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Masaoka T, Vanuytsel T, Vanormelingen C, Kindt S, Salim Rasoel S, Boesmans W, De Hertogh G, Farré R, Berghe PV, Tack J. A spontaneous animal model of intestinal dysmotility evoked by inflammatory nitrergic dysfunction. PLoS One 2014; 9:e95879. [PMID: 24819503 PMCID: PMC4018386 DOI: 10.1371/journal.pone.0095879] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Accepted: 04/01/2014] [Indexed: 01/08/2023] Open
Abstract
Background and Aims Recent reports indicate the presence of low grade inflammation in functional gastrointestinal disorders (FGID), in these cases often called “post-inflammatory” FGIDs. However, suitable animal models to study these disorders are not available. The Biobreeding (BB) rat consists of a diabetes-resistant (BBDR) and a diabetes-prone (BBDP) strain. In the diabetes-prone strain, 40–60% of the animals develop diabetes and concomitant nitrergic dysfunction. Our aim was to investigate the occurrence of intestinal inflammation, nitrergic dysfunction and intestinal dysmotility in non-diabetic animals. Methods Jejunal inflammation (MPO assay, Hematoxylin&Eosin staining and inducible nitric oxide synthase (iNOS) mRNA expression), in vitro jejunal motility (video analysis) and myenteric neuronal numbers (immunohistochemistry) were assessed in control, normoglycaemic BBDP and diabetic BBDP rats. To study the impact of iNOS inhibition on these parameters, normoglycaemic BBDP rats were treated with aminoguanidine. Results Compared to control, significant polymorphonuclear (PMN) cell infiltration, enhanced MPO activity, increased iNOS mRNA expression and a decreased ratio of nNOS to Hu-C/D positive neurons were observed in both normoglycaemic and diabetic BBDP rats. Aminoguanidine treatment decreased PMN infiltration, iNOS mRNA expression and MPO activity. Moreover, it restored the ratio of nNOS to Hu-C/D positive nerves in the myenteric plexus and decreased the abnormal jejunal elongation and dilation observed in normoglycaemic BBDP rats. Conclusions Aminoguanidine treatment counteracts the inflammation-induced nitrergic dysfunction and prevents dysmotility, both of which are independent of hyperglycaemia in BB rats. Nitrergic dysfunction may contribute to the pathophysiology of “low-grade inflammatory” FGIDs. Normoglycaemic BBDP rats may be considered a suitable animal model to study the pathogenesis of FGIDs.
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Affiliation(s)
- Tatsuhiro Masaoka
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Tim Vanuytsel
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Christophe Vanormelingen
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Sebastien Kindt
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Shadea Salim Rasoel
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Werend Boesmans
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Gert De Hertogh
- Department of Pathology, University of Leuven, Leuven, Belgium
| | - Ricard Farré
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Pieter Vanden Berghe
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Jan Tack
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
- * E-mail:
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Bhetwal BP, An C, Baker SA, Lyon KL, Perrino BA. Impaired contractile responses and altered expression and phosphorylation of Ca(2+) sensitization proteins in gastric antrum smooth muscles from ob/ob mice. J Muscle Res Cell Motil 2013; 34:137-49. [PMID: 23576331 DOI: 10.1007/s10974-013-9341-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 03/27/2013] [Indexed: 12/21/2022]
Abstract
Diabetic gastroparesis is a common complication of diabetes, adversely affecting quality of life with symptoms of abdominal discomfort, nausea, and vomiting. The pathogenesis of this complex disorder is not well understood, involving abnormalities in the extrinsic and enteric nervous systems, interstitial cells of Cajal (ICCs), smooth muscles and immune cells. The ob/ob mouse model of obesity and diabetes develops delayed gastric emptying, providing an animal model for investigating how gastric smooth muscle dysfunction contributes to the pathophysiology of diabetic gastroparesis. Although ROCK2, MYPT1, and CPI-17 activities are reduced in intestinal motility disorders, their functioning has not been investigated in diabetic gastroparesis. We hypothesized that reduced expression and phosphorylation of the myosin light chain phosphatase (MLCP) inhibitory proteins MYPT1 and CPI-17 in ob/ob gastric antrum smooth muscles could contribute to the impaired antrum smooth muscle function of diabetic gastroparesis. Spontaneous and carbachol- and high K(+)-evoked contractions of gastric antrum smooth muscles from 7 to 12 week old male ob/ob mice were reduced compared to age- and strain-matched controls. There were no differences in spontaneous and agonist-evoked intracellular Ca(2+) transients and myosin light chain kinase expression. The F-actin:G-actin ratios were similar. Rho kinase 2 (ROCK2) expression was decreased at both ages. Basal and agonist-evoked MYPT1 and myosin light chain 20 phosphorylation, but not CPI-17 phosphorylation, was reduced compared to age-matched controls. These findings suggest that reduced MLCP inhibition due to decreased ROCK2 phosphorylation of MYPT1 in gastric antrum smooth muscles contributes to the antral dysmotility of diabetic gastroparesis.
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Affiliation(s)
- Bhupal P Bhetwal
- Department of Physiology & Cell Biology, Center of Biomedical Research Excellence, University of Nevada School of Medicine, CMM 203E-MS 0575, 1664 N Virginia St, Reno, NV 89557, USA
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6
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Bhetwal BP, An CL, Fisher SA, Perrino BA. Regulation of basal LC20 phosphorylation by MYPT1 and CPI-17 in murine gastric antrum, gastric fundus, and proximal colon smooth muscles. Neurogastroenterol Motil 2011; 23:e425-36. [PMID: 21883701 PMCID: PMC3173524 DOI: 10.1111/j.1365-2982.2011.01769.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Myosin light chain kinase (MLCK) and myosin light chain phosphatase (MLCP) govern myosin light chain (LC20) phosphorylation and smooth muscle contraction. Rho kinase (ROK) inhibits MLCP, resulting in greater LC20 phosphorylation and force generation at a given [Ca(2+) ](i) . Here, we investigate the role of ROK in regulating LC20 phosphorylation and spontaneous contractions of gastric fundus, gastric antrum, and proximal colon smooth muscles. METHODS Protein and phosphorylation levels were determined by western blotting. The effects of Y27632, nicardipine, and GF109203X on phosphorylation levels and contraction were measured. KEY RESULTS γ-Actin expression is similar in all three smooth muscles. LC20 and pS19 are highest, but ROK1 and ROK2 are lowest, in antrum and proximal colon smooth muscles. LZ +/- myosin phosphatase targeting subunit 1 (MYPT1), CPI-17, and pT696, pT853, and pT38 are highest in fundus and proximal colon smooth muscles. Myosin phosphatase-rho interacting protein (M-RIP) expression is lowest in fundus, and highest in antrum and proximal colon smooth muscles. Y27632 reduced pT853 in each smooth muscle, but reduced pT696 only in fundus smooth muscles. Nicardipine had no effect on pT38 in each smooth muscle, while GF109203X reduced pT38 in proximal colon and fundus smooth muscles. Y27632 or nicardipine reduced pS19 in proximal colon and fundus smooth muscles. Y27632 or nicardipine inhibited antrum and proximal colon smooth muscle spontaneous contractions, but only Y27632 reduced fundus smooth muscle tone. Zero external Ca(2+) relaxed each smooth muscle and abolished LC20 phosphorylation. CONCLUSIONS & INFERENCES Organ-specific mechanisms involving the MLCP interacting proteins LZ +/- MYPT1, M-RIP, and CPI-17 are critical to regulating basal LC20 phosphorylation in gastrointestinal smooth muscles.
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Affiliation(s)
- Bhupal P. Bhetwal
- Department of Physiology & Cell Biology, Center of Biomedical Research Excellence, University of Nevada School of Medicine, Reno, NV, USA
| | - Chang Long An
- Department of Physiology & Cell Biology, Center of Biomedical Research Excellence, University of Nevada School of Medicine, Reno, NV, USA
| | - Steven A. Fisher
- Departments of Medicine (Cardiology), and Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Brian A. Perrino
- Department of Physiology & Cell Biology, Center of Biomedical Research Excellence, University of Nevada School of Medicine, Reno, NV, USA
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Gerspach AC, Steinert RE, Schönenberger L, Graber-Maier A, Beglinger C. The role of the gut sweet taste receptor in regulating GLP-1, PYY, and CCK release in humans. Am J Physiol Endocrinol Metab 2011; 301:E317-25. [PMID: 21540445 DOI: 10.1152/ajpendo.00077.2011] [Citation(s) in RCA: 134] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The recent identification of sweet taste receptors in the gastrointestinal tract has important implications in the control of food intake and glucose homeostasis. Lactisole can inhibit the sweet taste receptor T1R2/T1R3. The objective was to use lactisole as a probe to investigate the physiological role of T1R2/T1R3 by assessing the effect of T1R2/T1R3 blockade on GLP-1, PYY, and CCK release in response to 1) intragastric administration of nutrients or 2) intraduodenal perfusion of nutrients. The study was performed as a randomized, double-blind, placebo-controlled crossover study that included 35 healthy subjects. In part I, subjects received intragastrically 75 g of glucose in 300 ml of water or 500 ml of a mixed liquid meal with or without lactisole. In part II, subjects received an intraduodenal perfusion of glucose (29.3 g glucose/100 ml; rate: 2.5 ml/min for 180 min) or a mixed liquid meal (same rate) with or without lactisole. The results were that 1) lactisole induced a significant reduction in GLP-1 and PYY but not CCK secretion in both the intragastric and the intraduodenal glucose-stimulated parts (P ≤ 0.05), 2) comparison of the inhibitory effect of lactisole showed a significantly greater suppression of the hormone response in the intragastric part (P = 0.023), and 3) lactisole had no effect on liquid meal-stimulated parameters. We conclude that T1R2/T1R3 is involved in glucose-dependent secretion of satiation peptides. However, the results of the liquid meal-stimulated parts show that the receptor alone is not responsible for peptide secretion.
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Affiliation(s)
- A C Gerspach
- Phase 1 Research Unit, Department of Biomedicine, University Hospital Basel, Basel, Switzerland
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Antonioli L, Fornai M, Colucci R, Ghisu N, Tuccori M, Awwad O, Bin A, Zoppellaro C, Castagliuolo I, Gaion RM, Giron MC, Blandizzi C. Control of enteric neuromuscular functions by purinergic A(3) receptors in normal rat distal colon and experimental bowel inflammation. Br J Pharmacol 2010; 161:856-71. [PMID: 20860664 DOI: 10.1111/j.1476-5381.2010.00917.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND AND PURPOSE Adenosine A(3) receptors mediate beneficial effects in experimental colitis, but their involvement in enteric neuromuscular functions during bowel inflammation is undetermined. This study investigated the regulatory role of A(3) receptors on colonic motility in the presence of experimental colitis. EXPERIMENTAL APPROACH Colitis was induced in rats by 2,4-dinitrobenzenesulfonic acid. A(3) receptors and adenosine deaminase (ADA, adenosine catabolic enzyme) mRNA were examined by RT-PCR. Tissue distribution of A(3) receptors was detected by confocal immunofluorescence. The effects of 2,3-ethyl-4,5-dipropyl-6-phenylpyridine-3-thiocarboxylate-5-carboxylate (MRS1523) (MRS, A(3) receptor antagonist), 2-chloro-N(6) -(3-iodobenzyl)-adenosine-5'-N-methyluronamide (2Cl-IB-MECA) (CIB, A(3) receptor agonist), dipyridamole (DIP, adenosine transport inhibitor) and ADA were assayed on contractile responses evoked by electrical stimulation (ES) or carbachol in colonic longitudinal muscle preparations (LMP). KEY RESULTS RT-PCR showed A(3) receptors and ADA mRNA in normal colon and their increased level in inflamed tissues. Immunofluorescence showed a predominant distribution of A(3) receptors in normal myenteric ganglia and an increased density during colitis. MRS enhanced ES-induced cholinergic contractions in normal LMP, but was less effective in inflamed tissues. After pretreatment with dipyridamole plus ADA, to reduce extracellular adenosine, CIB decreased cholinergic motor responses of normal LMP to ES, with enhanced efficacy in inflamed LMP. A(3) receptor ligands did not affect carbachol-induced contractions in LMP from normal or inflamed colon. CONCLUSIONS AND IMPLICATIONS Normally, adenosine modulated colonic cholinergic motility via activation of A(3) receptors in the myenteric plexus. A(3) receptor-mediated tonic inhibitory control by adenosine was impaired in inflamed bowel, despite increased density of functioning and pharmacologically recruitable A(3) receptors.
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Affiliation(s)
- L Antonioli
- Division of Pharmacology and Chemotherapy, Department of Internal Medicine, University of Pisa, Pisa, Italy
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