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Brooke AK, Murrow DP, Caldwell KCN, Witt CE, Ross AE. Measuring neuron-regulated immune cell physiology via the alpha-2 adrenergic receptor in an ex vivo murine spleen model. Cell Mol Life Sci 2023; 80:354. [PMID: 37945921 PMCID: PMC11071927 DOI: 10.1007/s00018-023-05012-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 09/27/2023] [Accepted: 10/23/2023] [Indexed: 11/12/2023]
Abstract
The communication between the nervous and immune systems plays a crucial role in regulating immune cell function and inflammatory responses. Sympathetic neurons, which innervate the spleen, have been implicated in modulating immune cell activity. The neurotransmitter norepinephrine (NE), released by sympathetic neurons, influences immune cell responses by binding to adrenergic receptors on their surface. The alpha-2 adrenergic receptor (α2AR), expressed predominantly on sympathetic neurons, has received attention due to its autoreceptor function and ability to modulate NE release. In this study, we used fast-scan cyclic voltammetry (FSCV) to provide the first subsecond measurements of NE released in the white pulp region of the spleen and validated it with yohimbine, a known antagonist of α2AR. For further application of FSCV in neuroimmunology, we investigated the extent to which subsecond NE from sympathetic neurons is important for immune cell physiology and cytokine production, focusing on tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), and interleukin-6 (IL-6). Our findings provide insights into the regulatory mechanisms underlying sympathetic-immune interactions and show the significance of using FSCV, a traditional neurochemistry technique, to study these neuroimmune mechanisms.
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Affiliation(s)
- Alexandra K Brooke
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA
| | - Daniel P Murrow
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA
| | - Kaejaren C N Caldwell
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA
| | - Colby E Witt
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA
| | - Ashley E Ross
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA.
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2
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Oliinyk OS, Ma C, Pletnev S, Baloban M, Taboada C, Sheng H, Yao J, Verkhusha VV. Deep-tissue SWIR imaging using rationally designed small red-shifted near-infrared fluorescent protein. Nat Methods 2023; 20:70-74. [PMID: 36456785 PMCID: PMC10725253 DOI: 10.1038/s41592-022-01683-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 10/18/2022] [Indexed: 12/05/2022]
Abstract
Applying rational design, we developed 17 kDa cyanobacteriochrome-based near-infrared (NIR-I) fluorescent protein, miRFP718nano. miRFP718nano efficiently binds endogenous biliverdin chromophore and brightly fluoresces in mammalian cells and tissues. miRFP718nano has maximal emission at 718 nm and an emission tail in the short-wave infrared (SWIR) region, allowing deep-penetrating off-peak fluorescence imaging in vivo. The miRFP718nano structure reveals the molecular basis of its red shift. We demonstrate superiority of miRFP718nano-enabled SWIR imaging over NIR-I imaging of microbes in the mouse digestive tract, mammalian cells injected into the mouse mammary gland and NF-kB activity in a mouse model of liver inflammation.
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Affiliation(s)
- Olena S Oliinyk
- Medicum, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Chenshuo Ma
- Department of Biomedical Engineering, School of Engineering, Duke University, Durham, NC, USA
| | - Sergei Pletnev
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Mikhail Baloban
- Department of Genetics and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Carlos Taboada
- Department of Biomedical Engineering, School of Engineering, Duke University, Durham, NC, USA
| | - Huaxin Sheng
- Department of Anesthesiology, School of Medicine, Duke University, Durham, NC, USA
| | - Junjie Yao
- Department of Biomedical Engineering, School of Engineering, Duke University, Durham, NC, USA.
| | - Vladislav V Verkhusha
- Medicum, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
- Department of Genetics and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, USA.
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3
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Yan JT, Zhu YZ, Liang L, Feng XY. NE-activated β 2-AR/β-arrestin 2/Src pathway mediates duodenal hyperpermeability induced by water-immersion restraint stress. Am J Physiol Cell Physiol 2023; 324:C133-C141. [PMID: 36440855 DOI: 10.1152/ajpcell.00412.2022] [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: 11/29/2022]
Abstract
Stress causes a rapid spike in norepinephrine (NE) levels, leading to gastrointestinal dysfunction. NE reduces the expression of tight junctions (TJs) and aggravates intestinal mucosal damage, but the regulatory mechanism is still unclear. The present study aimed to investigate the molecular mechanisms underlying the regulation of stress-associated duodenal hyperpermeability by NE. Fluorescein isothiocyanate-dextran permeability, transepithelial resistance, immunofluorescence, Western blot, and high-performance liquid chromatography analysis were used in water-immersion restraint stress (WIRS) rats in this study. The results indicate that the duodenal permeability, degradation of TJs, mucosal NE, and β2-adrenergic receptor (β2-AR) increased in WIRS rats. The duodenal intracellular cyclic adenosine monophosphate levels were decreased, whereas the expression of β-arrestin 2 negatively regulates G protein-coupled receptors signaling, was significantly increased. Src recruitment was mediated by β-arrestin; thus, the levels of Src kinase activation were enhanced in WIRS rats. NE depletion, β2-AR, or β-arrestin 2 blockade significantly decreased mucosal permeability and increased TJs expression, suggesting improved mucosal barrier function. Moreover, NE induced an increased duodenal permeability of normal rats with activated β-arrestin 2/Src signaling, which was significantly inhibited by β2-AR blockade. The present findings demonstrate that the enhanced NE induced an increased duodenal permeability in WIRS rats through the activated β2-AR/β-arrestin 2/Src pathway. This study provides novel insight into the molecular mechanism underlying the regulation of NE on the duodenal mucosal barrier and a new target for treating duodenal ulcers induced by stress.
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Affiliation(s)
- Jing-Ting Yan
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.,Department of Anesthesiology, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Shandong Institute of Anesthesia and Respiratory Critical Medicine, Jinan, China
| | - Yin-Zhe Zhu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Liang Liang
- Grade 2020 Pediatrics, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Xiao-Yan Feng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
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4
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Olaitan Balogun S, Sabino Damazo A, Pavan E, de Freitas Figueiredo F, Arunachalam K, de Souza Mesquita LM, Vilegas W, Tabajara de Oliveira Martins D. Evidence for the Involvement of Cytokines Modulation and Prokinetic Properties in Gastric Ulcer Healing Effects of Helicteres sacarolha A. St.-Hil. A. Juss. Chem Biodivers 2022; 19:e202200322. [PMID: 36269048 DOI: 10.1002/cbdv.202200322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 10/19/2022] [Indexed: 12/27/2022]
Abstract
Preparations of Helicteres sacarolha (Malvaceae) leaves and roots are used in the form of decoction, infusion or maceration, to treat gastrointestinal disturbances, among others. Studies supporting some of its ethnomedicinal uses are still incipient. The present study aimed to investigate it potential effect on chronic ulcer, ulcerative colitis and possible prokinetic activities as part of its mechanism of action. The powdered leaves of Helicteres sacarolha (HEHs) was prepared by maceration in 70 % hydroethanolic solution. Its qualitative phytochemical constituents were investigated by direct flow injection analysis coupled to atmospheric pressure chemical ionization ion trap tandem mass spectrometry (FIA-APCI-IT-MSn ). The gastric ulcer healing effect was evaluated in acetic acid induced chronic ulcer in mice and the lesions were evaluated, including analysis of blood plasma cytokine levels. The prokinetic properties (gastric emptying and intestinal transit) were carried out in mice. Potential anti-ulcerative colitis activity was evaluated in rats using 2,4,6-trinitrobenzenesulfonic acid (5 % TNBS) -induced colitis. All animal experiments were carried out at the doses of 20, 50 and 250 mg/kg (p.o.). Eight compounds were putatively identified, specifically lariciresinol, and its derivatives, kaempferol derivatives and Tricin-O-Glc. The extract promoted increased gastric ulcer healing at all doses tested. Modulation of the cytokines involved inhibition of some key pro-inflammatory cytokines with maximum effect on IL-1β (70 %, 50 mg/kg, p<0.05), TNF-α (79 %, 20 mg/kg, p<0.01), and in the anti-inflammatory cytokines, namely IL-10 (57 %, 50 mg/kg, p<0.05) and IL-17 (79 %, only at 50 mg/kg, p<0.05). Histological findings demonstrated a mitigated inflammatory activity, and tissues undergoing regeneration. HEHs treatment caused delayed gastric emptying, and increased intestinal transit, but had no effect in the experimentally induced ulcerative colitis. We report for the first time putatively the presence of Lariciresinol and tricin derivatives from the hydroethanolic leaves extract of H. sacarolha. Its possible mechanism of actions of gastric ulcer healing involves cytokines modulation, mitigation of inflammatory response and tissue regeneration and provoked opposing effect in the gastrointestinal system. The present study demonstrates the therapeutic potential of H. sacarolha leaves used in Brazilian ethnomedicine in the treatment of chronic gastric ulcer.
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Affiliation(s)
- Sikiru Olaitan Balogun
- Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados (UFGD), 79804-970, Mato Grosso do Sul, Brazil.,Área de Farmacologia, Departamento de Ciências Básicas em Saúde, Faculdade de Medicina, Universidade Federal de Mato Grosso (UFMT), Cuiabá, MT, Brazil
| | - Amilcar Sabino Damazo
- Area of Histology, Department of Basic Health Sciences, Faculty of Medicine, Universidade Federal de Mato Grosso (UFMT), 78060-900, MT, Cuiabá, Brazil
| | - Eduarda Pavan
- Área de Farmacologia, Departamento de Ciências Básicas em Saúde, Faculdade de Medicina, Universidade Federal de Mato Grosso (UFMT), Cuiabá, MT, Brazil
| | - Fabiana de Freitas Figueiredo
- Área de Farmacologia, Departamento de Ciências Básicas em Saúde, Faculdade de Medicina, Universidade Federal de Mato Grosso (UFMT), Cuiabá, MT, Brazil
| | - Karuppusamy Arunachalam
- Área de Farmacologia, Departamento de Ciências Básicas em Saúde, Faculdade de Medicina, Universidade Federal de Mato Grosso (UFMT), Cuiabá, MT, Brazil.,Programa de Pós-graduação em Saúde e Desenvolvimento da Região Centro-Oeste, Centro de Estudos em Células Tronco, Terapia Celular e Genética Toxicológica (CeTroGen), Faculdade de Medicina Dr. Hélio Mandetta (FAMED), Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil.,Key Laboratory of Economic Plants and Biotechnology and the Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, P. R. China
| | | | - Wagner Vilegas
- UNESP - São Paulo State University, c, coastal campus of S. Vicente, São Vicente, SP, 11.330-900, Brazil
| | - Domingos Tabajara de Oliveira Martins
- Área de Farmacologia, Departamento de Ciências Básicas em Saúde, Faculdade de Medicina, Universidade Federal de Mato Grosso (UFMT), Cuiabá, MT, Brazil
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5
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Han QQ, Li XY, Wang YX. Dexmedetomidine attenuates lipopolysaccharide-induced inflammation through macrophageal IL-10 expression following α7 nAchR activation. Int Immunopharmacol 2022; 109:108920. [PMID: 35691275 DOI: 10.1016/j.intimp.2022.108920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 05/22/2022] [Accepted: 05/31/2022] [Indexed: 11/05/2022]
Abstract
Dexmedetomidine, a highly selective α2-adrenoceptor agonist, has been recently reported to alleviate systemic inflammatory response induced by lipopolysaccharide (LPS), in addition to its sedative, analgesic, bradycardic and hypotensive properties. This study aimed to illustrate the molecular mechanisms underlying dexmedetomidine-induced anti-inflammation. In the LPS-pretreated mice, subcutaneous injection of dexmedetomidine reduced the spleen weight as well as serum and spleen expression of proinflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1β, and increased serum and spleen expression of IL-10, a known anti-inflammatory cytokine. In addition, dexmedetomidine-attenuated proinflammatory cytokine reduction was entirely inhibited by selective α7 nicotinic acetylcholine receptor (nAChR) antagonist methyllycaconitine but not α2-adrenoceptor antagonist yohimbine. Dexmedetomidine also increased macrophageal IL-10 expression in the presence and absence of LPS, which was also attenuated by methyllycaconitine but not yohimbine. Furthermore, the stimulatory effect of dexmedetomidine on the expression of IL-10 was also reduced by the α7 nAChR gene silencer siRNA/α7 nAChR. Lastly, pretreatment with the IL-10 neutralizing antibody reversed dexmedetomidine-supressed expression of proinflammatory cytokines. Our findings illustrate that dexmedetomidine-induced anti-inflammation is through macrophageal expression of IL-10 following activation of α7 nAchRs but not α2-adrenoceptors.
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Affiliation(s)
- Qiao-Qiao Han
- King's Lab, Shanghai Jiao Tong University School of Pharmacy, Shanghai 200240, China; Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai 200025, China
| | - Xin-Yan Li
- King's Lab, Shanghai Jiao Tong University School of Pharmacy, Shanghai 200240, China.
| | - Yong-Xiang Wang
- King's Lab, Shanghai Jiao Tong University School of Pharmacy, Shanghai 200240, China.
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Wang D, Zhang H, Vu T, Zhan Y, Malhotra A, Wang P, Chitgupi U, Rai A, Zhang S, Wang L, Huizinga JD, Lovell JF, Xia J. Trans-illumination intestine projection imaging of intestinal motility in mice. Nat Commun 2021; 12:1682. [PMID: 33727562 PMCID: PMC7966380 DOI: 10.1038/s41467-021-21930-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 02/18/2021] [Indexed: 02/07/2023] Open
Abstract
Functional intestinal imaging holds importance for the diagnosis and evaluation of treatment of gastrointestinal diseases. Currently, preclinical imaging of intestinal motility in animal models is performed either invasively with excised intestines or noninvasively under anesthesia, and cannot reveal intestinal dynamics in the awake condition. Capitalizing on near-infrared optics and a high-absorbing contrast agent, we report the Trans-illumination Intestine Projection (TIP) imaging system for free-moving mice. After a complete system evaluation, we performed in vivo studies, and obtained peristalsis and segmentation motor patterns of free-moving mice. We show the in vivo typical segmentation motor pattern, that was previously shown in ex vivo studies to be controlled by intestinal pacemaker cells. We also show the effects of anesthesia on motor patterns, highlighting the possibility to study the role of the extrinsic nervous system in controlling motor patterns, which requires unanesthetized live animals. Combining with light-field technologies, we further demonstrated 3D imaging of intestine in vivo (3D-TIP). Importantly, the added depth information allows us to extract intestines located away from the abdominal wall, and to quantify intestinal motor patterns along different directions. The TIP system should open up avenues for functional imaging of the GI tract in conscious animals in natural physiological states.
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Affiliation(s)
- Depeng Wang
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Huijuan Zhang
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Tri Vu
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Ye Zhan
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Akash Malhotra
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Pei Wang
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Upendra Chitgupi
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Aliza Rai
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Sizhe Zhang
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Lidai Wang
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Jan D Huizinga
- Farncombe Family Digestive Health Research Institute, Department of Medicine, McMaster University, Ontario, Canada
| | - Jonathan F Lovell
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Jun Xia
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA.
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7
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Grasa L, Gonzalo S, De Martino A, Murillo MD. The lipopolysaccharide from Escherichia coli O127:B8 induces inflammation and motility disturbances in rabbit ileum. WORLD RABBIT SCIENCE 2017. [DOI: 10.4995/wrs.2017.5160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
<p>The aim of this work was to evaluate the effects of lipopolysaccharide (LPS) from <em>Escherichia coli </em>O127:B8 on the expression of toll-like receptor 4 (TLR4), the histology, and motor function in rabbit ileum. Rabbits were injected intravenously with saline or LPS (100 μg/kg, 2 h). The mRNA expression and localization of TLR4 were determined by reverse transcriptase-PCR and immunofluorescence, respectively. Histological damage induced by LPS was evaluated in sections of ileum stained with haematoxylin and eosin. Contractility studies of ileum were performed in an organ bath. The mRNA expression of TLR4 decreased in the muscular but not in the mucosal layer of rabbits treated with LPS. TLR4 was localised in both the mucosal and muscular layers of rabbit ileum. LPS induced intestinal inflammation and altered the spontaneous contractions and the serotonin-, acetylcholine- and KCl-induced contractions. In conclusion, LPS from <em>E. coli </em>O127:B8 induced a decrease in the mRNA expression of TLR4, an inflammatory response, and changes in the contractility of rabbit ileum.</p>
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8
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Tachibana T, Ogino M, Makino R, Khan MSI, Cline MA. Lipopolysaccharide reduces food passage rate from the crop by a prostaglandin-independent mechanism in chickens. Br Poult Sci 2016; 58:100-106. [PMID: 27871194 PMCID: PMC5359745 DOI: 10.1080/00071668.2016.1237768] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
1. We examined the effect of lipopolysaccharide (LPS), a component of Gram-negative bacteria, on food passage in the digestive tract of chickens (Gallus gallus) in order to clarify whether bacterial infection affects food passage in birds. 2. Food passage in the crop was significantly reduced by intraperitoneal (IP) injection of LPS while it did not affect the number of defecations, suggesting that LPS may affect food passage only in the upper digestive tract. 3. Similar to LPS, prostaglandin E2 (PGE2), one of the mediators of LPS, also reduced crop-emptying rate in chickens while it had no effect on the number of defecations. 4. Pretreatment with indomethacin, which is an inhibitor of cyclooxygenase (COX), a prostaglandin synthase, had no effect on LPS-induced inhibition of crop emptying. 5. IP injection of LPS did not affect the mRNA expression of COX2 in the upper digestive tract of chickens. 6. It is therefore likely that LPS and PGE2 reduced food passage rate in the crop by a prostaglandin-independent pathway in chickens.
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Affiliation(s)
- T Tachibana
- a Department of Agrobiological Science, Faculty of Agriculture , Ehime University , Matsuyama , Japan
| | - M Ogino
- a Department of Agrobiological Science, Faculty of Agriculture , Ehime University , Matsuyama , Japan
| | - R Makino
- a Department of Agrobiological Science, Faculty of Agriculture , Ehime University , Matsuyama , Japan
| | - M S I Khan
- b Department of Anatomy and Embryology , Ehime University Graduate School of Medicine , Toon , Japan
| | - M A Cline
- c Department of Animal and Poultry Sciences , Virginia Polytechnic Institute and State University , Blacksburg , VA , USA
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Cheng J, Xiong Z, Duffney LJ, Wei J, Liu A, Liu S, Chen GJ, Yan Z. Methylphenidate exerts dose-dependent effects on glutamate receptors and behaviors. Biol Psychiatry 2014; 76:953-62. [PMID: 24832867 PMCID: PMC4194277 DOI: 10.1016/j.biopsych.2014.04.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 03/17/2014] [Accepted: 04/01/2014] [Indexed: 12/15/2022]
Abstract
BACKGROUND Methylphenidate (MPH), a psychostimulant drug used to treat attention-deficit/hyperactivity disorder, produces the effects of increasing alertness and improving attention. However, misuse of MPH has been associated with an increased risk of aggression and psychosis. We sought to determine the molecular mechanism underlying the complex actions of MPH. METHODS Adolescent (4-week-old) rats were given one injection of MPH at different doses. The impact of MPH on glutamatergic signaling in pyramidal neurons of prefrontal cortex was measured. Behavioral changes induced by MPH were also examined in parallel. RESULTS Administration of low-dose (.5 mg/kg) MPH selectively potentiated N-methyl-D-aspartate receptor (NMDAR)-mediated excitatory postsynaptic currents (EPSCs) via adrenergic receptor activation, whereas high-dose (10 mg/kg) MPH suppressed both NMDAR-mediated and alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor-mediated EPSCs. The dual effects of MPH on EPSCs were associated with bidirectional changes in the surface level of glutamate receptor subunits. Behavioral tests also indicated that low-dose MPH facilitated prefrontal cortex-mediated temporal order recognition memory and attention. Animals injected with high-dose MPH exhibited significantly elevated locomotive activity. Inhibiting the function of synaptosomal-associated protein 25, a key SNARE protein involved in NMDAR exocytosis, blocked the increase of NMDAR-mediated EPSCs by low-dose MPH. In animals exposed to repeated stress, administration of low-dose MPH effectively restored NMDAR function and temporal order recognition memory via a mechanism dependent on synaptosomal-associated protein 25. CONCLUSIONS These results provide a potential mechanism underlying the cognitive-enhancing effects of low-dose MPH as well as the psychosis-inducing effects of high-dose MPH.
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Affiliation(s)
- Jia Cheng
- Department of Physiology and Biophysics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA
| | - Zhe Xiong
- Department of Physiology and Biophysics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA
| | - Lara J. Duffney
- Department of Physiology and Biophysics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA
| | - Jing Wei
- Department of Physiology and Biophysics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA
| | - Aiyi Liu
- Department of Physiology and Biophysics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA,Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Sihang Liu
- Department of Physiology and Biophysics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA
| | - Guo-Jun Chen
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Zhen Yan
- Department of Physiology and Biophysics, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York; Department of Physiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.
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10
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Fichna J, Dicay M, Hirota SA, Traboulsi D, Macdonald JA, Janecka A, Beck PL, Zjawiony JK, Macnaughton WK, Storr MA. Differential effects of salvinorin A on endotoxin-induced hypermotility and neurogenic ion transport in mouse ileum. Neurogastroenterol Motil 2011; 23:583-e212. [PMID: 21414104 DOI: 10.1111/j.1365-2982.2011.01699.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Salvinorin A (SA) is the principal active ingredient of Salvia divinorum, with an established inhibitory action on gastrointestinal (GI) transit and colonic ion transport in mice. Under normal conditions, the effects of SA are mediated by kappa opioid (KOR) and cannabinoid (CB1 and CB2) receptors. However, the role of SA in pathophysiological conditions remains unresolved. The aim of this study was to characterize the in vitro and in vivo effects of SA on mouse ileum after endotoxin challenge. METHODS Changes in GI motility were studied in vitro, using smooth muscle preparations from the mouse ileum. In vivo, the fecal pellet output and small intestinal fluid content were measured. Neurogenic ion transport and intestinal permeability were examined using Ussing chambers. In addition, Western blot analysis of mucosa was performed and plasma nitrite/nitrate levels were determined. KEY RESULTS Salvinorin A inhibited endotoxin-induced ileal hypercontractility via KOR, CB1, and CB2 receptors. Neurogenic ion transport, which was significantly reduced after endotoxin challenge, was normalized by SA through a nitric oxide synthase (NOS)-dependent mechanism. Western blot analysis and plasma nitrite/nitrate level quantitation confirmed the involvement of NOS in the regulatory action of SA. CONCLUSIONS & INFERENCES This is the first report showing differential effects of SA on motor and secretory activity in mouse GI during endotoxemia. The outcomes of our study imply possible novel applications of SA and its analogs in the treatment of GI disorders.
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Affiliation(s)
- J Fichna
- Division of Gastroenterology, Department of Medicine, Snyder Institute of Infection, Immunity and Inflammation (III), University of Calgary, Calgary, AB, Canada
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Almeida RL, David RB, Constancio J, Fracasso JF, Menani JV, De Luca LA. Inhibition of sodium appetite by lipopolysaccharide: involvement of alpha2-adrenoceptors. Am J Physiol Regul Integr Comp Physiol 2011; 301:R185-92. [PMID: 21474430 DOI: 10.1152/ajpregu.00555.2009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Lipopolysaccharide (LPS), an endotoxin from the wall of Escherichia coli, produces a general behavioral inhibition and affects several aspects of fluid-electrolyte balance. LPS inhibits thirst; however, it is not clear if it also inhibits sodium appetite. The present results show that LPS (0.3-2.5 mg/kg body wt) injected intraperitoneally produces a dose-dependent reduction of sodium appetite expressed as 0.3 M NaCl intake induced by sodium depletion (furosemide plus removal of ambient sodium for 24 h). The high doses of LPS (1.2-2.5 mg/kg) also produced transient hypothermia at the beginning of the sodium appetite test; however, no dose produced hyperthermia. LPS also increased the stomach liquid content (an index of gastric emptying) after a load of 0.3 M NaCl given intragastrically by gavage to sodium-depleted rats. The α(2)-adrenoceptor antagonist yohimbine (5 mg/kg ip) abolished the effect of LPS on 0.3 M NaCl intake, without changing the effect of LPS on gastric emptying. Injection of RX-821002 (160 nmol), another α(2)-adrenoceptor antagonist, in the lateral cerebral ventricle (LV) also reversed the inhibition of sodium appetite produced by LPS. Yohimbine intraperitoneally or RX-821002 in the LV alone had no effect on sodium intake. Although yohimbine plus LPS produced a slight hypotension, RX-821002 plus LPS produced no change in arterial pressure, suggesting that the blockade of the effects of LPS on sodium intake by the α(2)-adrenoceptor antagonists is independent from changes in arterial pressure. The results suggest an inhibitory role for LPS in sodium appetite that is mediated by central α(2)-adrenoceptors.
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Affiliation(s)
- R L Almeida
- Dept. of Physiology and Pathology, School of Dentistry, São Paulo State University, UNESP, Rua Humaitá, 1680, Araraquara, São Paulo, 14801-903, Brazil
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Peacock WF, Breitmeyer JB, Pan C, Smith WB, Royal MA. A randomized study of the efficacy and safety of intravenous acetaminophen compared to oral acetaminophen for the treatment of fever. Acad Emerg Med 2011; 18:360-6. [PMID: 21496138 DOI: 10.1111/j.1553-2712.2011.01043.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The purpose of this study was to assess the safety and dynamics of the onset of antipyretic efficacy of intravenous (IV) acetaminophen versus oral (PO) acetaminophen in the treatment of endotoxin-induced fever. METHODS This randomized, double-blind, double-dummy, single-dose study was conducted at a single center in the United States in healthy volunteer adult males with an endotoxin-induced fever to assess the antipyretic efficacy and safety of IV acetaminophen 1 g versus PO acetaminophen 1 g over 6 hours. Subjects who achieved a sufficient fever response to a test dose of reference standard endotoxin were randomly assigned to receive either IV acetaminophen and PO placebo (n = 54) or PO acetaminophen and IV placebo (n = 51). The primary efficacy outcome was the weighted sum of temperature differences from baseline at time T0 through T120 minutes. Safety evaluations included adverse event (AE), physical exam, and laboratory assessments. RESULTS Of 105 subjects receiving study medication, 24 vomited within 2 hours postdose (PO acetaminophen, n = 15; and IV acetaminophen, n = 9) and were excluded from the modified intent-to-treat population that consisted of 36 and 45 subjects treated with PO and IV acetaminophen, respectively. While this was done to not confer an advantage to the IV formulation, a sensitivity analysis including these subjects did not change the overall efficacy results. Statistically significant results favoring IV acetaminophen were observed for the primary endpoint (weighted sum of temperature differences over 120 minutes, p = 0.0039) and also at each time point from T30 to T90 minutes, although the maximum mean observed temperature difference was only 0.3°C. The study drugs were well tolerated. The AE frequency was comparable between the IV and PO groups. CONCLUSIONS A single dose of IV acetaminophen is as safe and effective in reducing endotoxin-induced fever as PO acetaminophen. IV acetaminophen may be useful where patients are unable to tolerate PO intake or when an earlier onset of action is desirable.
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Affiliation(s)
- W Frank Peacock
- Department of Emergency Medicine, The Cleveland Clinic, OH, USA.
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Wong DM, Davis JL, White NA. Motility of the equine gastrointestinal tract: Physiology and pharmacotherapy. EQUINE VET EDUC 2011. [DOI: 10.1111/j.2042-3292.2010.00173.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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De Winter BY, De Man JG. Interplay between inflammation, immune system and neuronal pathways: Effect on gastrointestinal motility. World J Gastroenterol 2010; 16:5523-35. [PMID: 21105185 PMCID: PMC2992670 DOI: 10.3748/wjg.v16.i44.5523] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Sepsis is a systemic inflammatory response representing the leading cause of death in critically ill patients, mostly due to multiple organ failure. The gastrointestinal tract plays a pivotal role in the pathogenesis of sepsis-induced multiple organ failure through intestinal barrier dysfunction, bacterial translocation and ileus. In this review we address the role of the gastrointestinal tract, the mediators, cell types and transduction pathways involved, based on experimental data obtained from models of inflammation-induced ileus and (preliminary) clinical data. The complex interplay within the gastrointestinal wall between mast cells, residential macrophages and glial cells on the one hand, and neurons and smooth muscle cells on the other hand, involves intracellular signaling pathways, Toll-like receptors and a plethora of neuroactive substances such as nitric oxide, prostaglandins, cytokines, chemokines, growth factors, tryptases and hormones. Multidirectional signaling between the different components in the gastrointestinal wall, the spinal cord and central nervous system impacts inflammation and its consequences. We propose that novel therapeutic strategies should target inflammation on the one hand and gastrointestinal motility, gastrointestinal sensitivity and even pain signaling on the other hand, for instance by impeding afferent neuronal signaling, by activation of the vagal anti-inflammatory pathway or by the use of pharmacological agents such as ghrelin and ghrelin agonists or drugs interfering with the endocannabinoid system.
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Kumar V, Sharma A. Is neuroimmunomodulation a future therapeutic approach for sepsis? Int Immunopharmacol 2010; 10:9-17. [DOI: 10.1016/j.intimp.2009.10.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Revised: 10/06/2009] [Accepted: 10/09/2009] [Indexed: 01/02/2023]
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Abstract
Surgical manipulation of the intestines activates intestinal macrophages that release cytokines and nitric oxide, which results in inhibition of intestinal motility. Subsequent infiltration of circulating leukocytes into the intestinal wall contributes to cytokine and nitric oxide release and exacerbates ileus. Other factors contributing to ileus are endotoxemia; edema of the intestine wall subsequent to excessive fluid therapy; hypocalcemia; and long abdominal incisions. Because treatment of ileus with prokinetic drugs has not proven to be very effective, efforts should be directed at reducing its severity. Strategies which reduce the severity of ileus include pretreatment with a nonsteroidal anti-inflammatory drug, minimizing the length of the abdominal incision, reducing intestinal manipulation, intraoperative lidocaine infusion, correction of hypocalcemia, limiting the volume of intravenous fluids to prevent intestinal edema, and administration of alpha(2) antagonists.
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Affiliation(s)
- Thomas J Doherty
- Department of Large Animal Clinical Sciences, The University of Tennessee College of Veterinary Medicine, 2407 River Drive, Knoxville, TN 37996, USA.
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