1
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Reich N, Hölscher C. Cholecystokinin (CCK): a neuromodulator with therapeutic potential in Alzheimer's and Parkinson's disease. Front Neuroendocrinol 2024; 73:101122. [PMID: 38346453 DOI: 10.1016/j.yfrne.2024.101122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/04/2024] [Accepted: 01/25/2024] [Indexed: 02/16/2024]
Abstract
Cholecystokinin (CCK) is a neuropeptide modulating digestion, glucose levels, neurotransmitters and memory. Recent studies suggest that CCK exhibits neuroprotective effects in Alzheimer's disease (AD) and Parkinson's disease (PD). Thus, we review the physiological function and therapeutic potential of CCK. The neuropeptide facilitates hippocampal glutamate release and gates GABAergic basket cell activity, which improves declarative memory acquisition, but inhibits consolidation. Cortical CCK alters recognition memory and enhances audio-visual processing. By stimulating CCK-1 receptors (CCK-1Rs), sulphated CCK-8 elicits dopamine release in the substantia nigra and striatum. In the mesolimbic pathway, CCK release is triggered by dopamine and terminates reward responses via CCK-2Rs. Importantly, activation of hippocampal and nigral CCK-2Rs is neuroprotective by evoking AMPK activation, expression of mitochondrial fusion modulators and autophagy. Other benefits include vagus nerve/CCK-1R-mediated expression of brain-derived neurotrophic factor, intestinal protection and suppression of inflammation. We also discuss caveats and the therapeutic combination of CCK with other peptide hormones.
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Affiliation(s)
- Niklas Reich
- The ALBORADA Drug Discovery Institute, University of Cambridge, Island Research Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0AH, UK; Faculty of Health and Medicine, Biomedical & Life Sciences Division, Lancaster University, Lancaster LA1 4YQ, UK.
| | - Christian Hölscher
- Second associated Hospital, Neurology Department, Shanxi Medical University, Taiyuan, Shanxi, China; Henan Academy of Innovations in Medical Science, Neurodegeneration research group, Xinzhen, Henan province, China
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2
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Leigh RS, Ruskoaho HJ, Kaynak BL. Cholecystokinin peptide signaling is regulated by a TBX5-MEF2 axis in the heart. Peptides 2021; 136:170459. [PMID: 33249116 DOI: 10.1016/j.peptides.2020.170459] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 11/15/2022]
Abstract
The procholecystokinin (proCCK) gene encodes a secreted peptide known to regulate the digestive, endocrine, and nervous systems. Though recently proposed as a biomarker for heart dysfunction, its physiological role in both the embryonic and adult heart is poorly understood, and there are no reports of tissue-specific regulators of cholecystokinin signaling in the heart or other tissues. In the present study, mRNA of proCCK was observed in cardiac tissues during mouse embryonic development, establishing proCCK as an early marker of differentiated cardiomyocytes which is later restricted to anatomical subdomains of the neonatal heart. Three-dimensional analysis of the expression of proCCK and CCKAR/CCKBR receptors was performed using in situ hybridization and optical projection tomography, illustrating chamber-specific expression patterns in the postnatal heart. Transcription factor motif analyses indicated developmental cardiac transcription factors TBX5 and MEF2C as upstream regulators of proCCK, and this regulatory activity was confirmed in reporter gene assays. proCCK mRNA levels were also measured in the infarcted heart and in response to cyclic mechanical stretch and endothelin-1, indicating dynamic transcriptional regulation which might be leveraged for improved biomarker development. Functional analyses of exogenous cholecystokinin octapeptide (CCK-8) administration were performed in differentiating mouse embryonic stem cells (mESCs), and the results suggest that CCK-8 does not act as a differentiation modulator of cardiomyocyte subtypes. Collectively, these findings indicate that proCCK is regulated at the transcriptional level by TBX5-MEF2 and neurohormonal signaling, informing use of proCCK as a biomarker and future strategies for upstream manipulation of cholecystokinin signaling in the heart and other tissues.
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Affiliation(s)
- Robert S Leigh
- Drug Research Programme, Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Heikki J Ruskoaho
- Drug Research Programme, Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Bogac L Kaynak
- Drug Research Programme, Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
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3
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Liu C, Chen K, Wang H, Zhang Y, Duan X, Xue Y, He H, Huang Y, Chen Z, Ren H, Wang H, Zeng C. Gastrin Attenuates Renal Ischemia/Reperfusion Injury by a PI3K/Akt/Bad-Mediated Anti-apoptosis Signaling. Front Pharmacol 2020; 11:540479. [PMID: 33343341 PMCID: PMC7740972 DOI: 10.3389/fphar.2020.540479] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 09/24/2020] [Indexed: 12/25/2022] Open
Abstract
Ischemic/reperfusion (I/R) injury is the primary cause of acute kidney injury (AKI). Gastrin, a gastrointestinal hormone, is involved in the regulation of kidney function of sodium excretion. However, whether gastrin has an effect on kidney I/R injury is unknown. Here we show that cholecystokinin B receptor (CCKBR), the gastrin receptor, was significantly up-regulated in I/R-injured mouse kidneys. While pre-administration of gastrin ameliorated I/R-induced renal pathological damage, as reflected by the levels of serum creatinine and blood urea nitrogen, hematoxylin and eosin staining and periodic acid-Schiff staining. The protective effect could be ascribed to the reduced apoptosis for gastrin reduced tubular cell apoptosis both in vivo and in vitro. In vitro studies also showed gastrin preserved the viability of hypoxia/reoxygenation (H/R)-treated human kidney 2 (HK-2) cells and reduced the lactate dehydrogenase release, which were blocked by CI-988, a specific CCKBR antagonist. Mechanistically, the PI3K/Akt/Bad pathway participates in the pathological process, because gastrin treatment increased phosphorylation of PI3K, Akt and Bad. While in the presence of wortmannin (1 μM), a PI3K inhibitor, the gastrin-induced phosphorylation of Akt after H/R treatment was blocked. Additionally, wortmannin and Akt inhibitor VIII blocked the protective effect of gastrin on viability of HK-2 cells subjected to H/R treatment. These studies reveals that gastrin attenuates kidney I/R injury via a PI3K/Akt/Bad-mediated anti-apoptosis signaling. Thus, gastrin can be considered as a promising drug candidate to prevent AKI.
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Affiliation(s)
- Chao Liu
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China
| | - Ken Chen
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China
| | - Huaixiang Wang
- Department of Lishilu Outpatient, General Hospital of the PLA Rocket Force, Beijing, China
| | - Ye Zhang
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China
| | - Xudong Duan
- Cardiovascular Research Center of Chongqing College, Department of Cardiology of Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
| | - Yuanzheng Xue
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China
| | - Hongye He
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China
| | - Yu Huang
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China
| | - Zhi Chen
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China
| | - Hongmei Ren
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China
| | - Hongyong Wang
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, Army Medical University, Chongqing, China.,Chongqing Institute of Cardiology & Chongqing Key Laboratory of Hypertension Research, Chongqing, China.,Cardiovascular Research Center of Chongqing College, Department of Cardiology of Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China.,State Key Laboratory of Trauma, Burns and Combined Injury, Daping Hospital, Army Medical University, Chongqing, China
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4
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Xu P, Gildea JJ, Zhang C, Konkalmatt P, Cuevas S, Bigler Wang D, Tran HT, Jose PA, Felder RA. Stomach gastrin is regulated by sodium via PPAR-α and dopamine D1 receptor. J Mol Endocrinol 2020; 64:53-65. [PMID: 31794424 PMCID: PMC7654719 DOI: 10.1530/jme-19-0053] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 12/03/2019] [Indexed: 12/14/2022]
Abstract
Gastrin, secreted by stomach G cells in response to ingested sodium, stimulates the renal cholecystokinin B receptor (CCKBR) to increase renal sodium excretion. It is not known how dietary sodium, independent of food, can increase gastrin secretion in human G cells. However, fenofibrate (FFB), a peroxisome proliferator-activated receptor-α (PPAR-α) agonist, increases gastrin secretion in rodents and several human gastrin-secreting cells, via a gastrin transcriptional promoter. We tested the following hypotheses: (1.) the sodium sensor in G cells plays a critical role in the sodium-mediated increase in gastrin expression/secretion, and (2.) dopamine, via the D1R and PPAR-α, is involved. Intact human stomach antrum and G cells were compared with human gastrin-secreting gastric and ovarian adenocarcinoma cells. When extra- or intracellular sodium was increased in human antrum, human G cells, and adenocarcinoma cells, gastrin mRNA and protein expression/secretion were increased. In human G cells, the PPAR-α agonist FFB increased gastrin protein expression that was blocked by GW6471, a PPAR-α antagonist, and LE300, a D1-like receptor antagonist. LE300 prevented the ability of FFB to increase gastrin protein expression in human G cells via the D1R, because the D5R, the other D1-like receptor, is not expressed in human G cells. Human G cells also express tyrosine hydroxylase and DOPA decarboxylase, enzymes needed to synthesize dopamine. G cells in the stomach may be the sodium sensor that stimulates gastrin secretion, which enables the kidney to eliminate acutely an oral sodium load. Dopamine, via the D1R, by interacting with PPAR-α, is involved in this process.
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Affiliation(s)
- Peng Xu
- Department of Pathology, The University of Virginia, Charlottesville, Virginia, USA
| | - John J Gildea
- Department of Pathology, The University of Virginia, Charlottesville, Virginia, USA
| | - Chi Zhang
- Department of Pathology, The University of Virginia, Charlottesville, Virginia, USA
| | - Prasad Konkalmatt
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University, School of Medicine & Health Sciences, Washington, District of Columbia, USA
| | - Santiago Cuevas
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University, School of Medicine & Health Sciences, Washington, District of Columbia, USA
| | - Dora Bigler Wang
- Department of Pathology, The University of Virginia, Charlottesville, Virginia, USA
| | - Hanh T Tran
- Department of Pathology, The University of Virginia, Charlottesville, Virginia, USA
| | - Pedro A Jose
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University, School of Medicine & Health Sciences, Washington, District of Columbia, USA
- Department of Pharmacology and Physiology, The George Washington University, School of Medicine & Health Sciences, Washington, District of Columbia, USA
| | - Robin A Felder
- Department of Pathology, The University of Virginia, Charlottesville, Virginia, USA
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Abstract
Gastric acid secretion (i) facilitates digestion of protein as well as absorption of micronutrients and certain medications, (ii) kills ingested microorganisms, including Helicobacter pylori, and (iii) prevents bacterial overgrowth and enteric infection. The principal regulators of acid secretion are the gastric peptides gastrin and somatostatin. Gastrin, the major hormonal stimulant for acid secretion, is synthesized in pyloric mucosal G cells as a 101-amino acid precursor (preprogastrin) that is processed to yield biologically active amidated gastrin-17 and gastrin-34. The C-terminal active site of gastrin (Trp-Met-Asp-Phe-NH2 ) binds to gastrin/CCK2 receptors on parietal and, more importantly, histamine-containing enterochromaffin-like (ECL) cells, located in oxyntic mucosa, to induce acid secretion. Histamine diffuses to the neighboring parietal cells where it binds to histamine H2 -receptors coupled to hydrochloric acid secretion. Gastrin is also a trophic hormone that maintains the integrity of gastric mucosa, induces proliferation of parietal and ECL cells, and is thought to play a role in carcinogenesis. Somatostatin, present in D cells of the gastric pyloric and oxyntic mucosa, is the main inhibitor of acid secretion, particularly during the interdigestive period. Somatostatin exerts a tonic paracrine restraint on gastrin secretion from G cells, histamine secretion from ECL cells, and acid secretion from parietal cells. Removal of this restraint, for example by activation of cholinergic neurons during ingestion of food, initiates and maximizes acid secretion. Knowledge regarding the structure and function of gastrin, somatostatin, and their respective receptors is providing novel avenues to better diagnose and manage acid-peptic disorders and certain cancers. Published 2020. Compr Physiol 10:197-228, 2020.
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Affiliation(s)
- Mitchell L Schubert
- Division of Gastroenterology, Department of Medicine, Virginia Commonwealth University Health System, Richmond, Virginia, USA.,Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, Virginia, USA
| | - Jens F Rehfeld
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
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Gorky J, Schwaber J. Conceptualization of a Parasympathetic Endocrine System. Front Neurosci 2019; 13:1008. [PMID: 31607849 PMCID: PMC6767939 DOI: 10.3389/fnins.2019.01008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Accepted: 09/05/2019] [Indexed: 12/18/2022] Open
Abstract
We here propose a parasympathetic endocrine system (PES) comprised of circulating peptides released from secretory cells in the gut, significantly modulated by vagal projections from the dorsal motor nucleus of the vagus (DMV). While most of these gut peptides mediate well-described satiety and digestive effects that increase parasympathetic control of digestion (Lee et al., 1994; Gutzwiller et al., 1999; Klok et al., 2007), they also have actions that are far-reaching and increase parasympathetic signaling broadly throughout the body. The actions beyond satiety that peptides like somatostatin, cholecystokinin, glucagon-like peptide 1, and vasoactive intestinal peptide have been well-examined, but not in a systematic way. Consideration has been given to the idea that these and other gut-derived peptides are part of an endocrine system has been partially considered (Rehfeld, 2012; Drucker, 2016), but that it is coordinated through parasympathetic control and may act to increase the actions of parasympathetic projections has not been formalized before. Here only gut-derived hormones are included although there are potentially other parasympathetically mediated factors released from other sites like lung and liver (Drucker, 2016). The case for the existence of the PES with the DMV as its integrative controller will be made through examination of an anatomical substrate and evidence of physiological control mechanisms as well as direct examples of PES antagonism of sympathetic signaling in mammals, including humans. The implications for this conceptual understanding of a PES reframe diseases like metabolic syndrome and may help underscore the role of the autonomic nervous system in the associated symptoms.
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Affiliation(s)
- Jonathan Gorky
- Daniel Baugh Institute for Functional Genomics and Computational Biology, Thomas Jefferson University, Philadelphia, PA, United States
| | - James Schwaber
- Daniel Baugh Institute for Functional Genomics and Computational Biology, Thomas Jefferson University, Philadelphia, PA, United States
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Abstract
Purpose of Review Hypertension is related to impaired metabolic homeostasis and can be regarded as a metabolic disorder. This review presents possible mechanisms by which metabolic disorders increase blood pressure (BP) and discusses the importance of the gut as a novel modulator of BP. Recent Findings Obesity and high salt intake are major risk factors for hypertension. There is a hypothesis of “salt-induced obesity”; i.e., high salt intake may tie to obesity. Heightened sympathetic nervous system (SNS) activity, especially in the kidney and brain, increases BP in obese patients. Adipokines, including adiponectin and leptin, and renin-angiotensin-aldosterone system (RAAS) contribute to hypertension. Adiponectin induced by a high-salt diet may decrease sodium/glucose cotransporter (SGLT) 2 expression in the kidney, which results in reducing BP. High salt can change secretions of adipokines and RAAS-related components. Evidence has been accumulating linking the gastrointestinal tract to BP. Glucagon-like peptide-1 (GLP-1) and ghrelin decrease BP in both rodents and humans. The sweet taste receptor in enteroendocrine cells increases SGLT1 expression and stimulates sodium/glucose absorption. Roux-en-Y gastric bypass improves glycemic and BP control due to reducing the activity of SGLT1. Na/H exchanger isoform 3 (NHE3) increases BP by stimulating the intestinal absorption of sodium. Gastrin functions as an intestinal sodium taste sensor and inhibits NHE3 activity. Intestinal mineralocorticoid receptors also regulate sodium absorption and BP due to changing ENaC activity. Gastric sensing of sodium induces natriuresis, and gastric distension increases BP. Changes in the composition and function of gut microbiota contribute to hypertension. A high-salt/fat diet may disrupt the gut barrier, which results in systemic inflammation, insulin resistance, and increased BP. Gut microbiota regulates BP by secreting vasoactive hormones and short-chain fatty acids. BP-lowering effects of probiotics and antibiotics have been reported. Bariatric surgery improves metabolic disorders and hypertension due to increasing GLP-1 secretion, decreasing leptin secretion and SNS activity, and changing gut microbiome composition. Strategies targeting the gastrointestinal system may be therapeutic options for improving metabolic abnormalities and reducing BP in humans. Summary SNS, brain, adipocytes, RAAS, the kidney, the gastrointestinal tract, and microbiota play important roles in regulating BP. Most notably, the gut could be a novel target for treatment of hypertension as a metabolic disorder.
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8
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Takahashi-Iwanaga H, Kimura S, Konno K, Watanabe M, Iwanaga T. Intrarenal signaling mediated by CCK plays a role in salt intake-induced natriuresis. Am J Physiol Renal Physiol 2017; 313:F20-F29. [DOI: 10.1152/ajprenal.00539.2016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 03/07/2017] [Accepted: 03/10/2017] [Indexed: 11/22/2022] Open
Abstract
The natriuretic hormone CCK exhibits its gene transcripts in total kidney extracts. To test the possibility of CCK acting as an intrarenal mediator of sodium excretion, we examined mouse kidneys by 1) an in situ hybridization technique for CCK mRNA in animals fed a normal- or a high-sodium diet; 2) immuno-electron microscopy for the CCK peptide, 3) an in situ hybridization method and immunohistochemistry for the CCK-specific receptor CCKAR; 4) confocal image analysis of receptor-mediated Ca2+ responses in isolated renal tubules; and 5) metabolic cage experiments for the measurement of urinary sodium excretion in high-salt-fed mice either treated or untreated with the CCKAR antagonist lorglumide. Results showed the CCK gene to be expressed intensely in the inner medulla and moderately in the inner stripe of the outer medulla, with the expression in the latter being enhanced by high sodium intake. Immunoreactivity for the CCK peptide was localized to the rough endoplasmic reticulum of the medullary interstitial cells in corresponding renal regions, confirming it to be a secretory protein. Gene transcripts, protein products, and the functional activity for CCKAR were consistently localized to the late proximal tubule segments (S2 and S3) in the medullary rays, and the outer stripe of the outer medulla. Lorglumide significantly diminished natriuretic responses of mice to a dietary sodium load without altering the glomerular filtration rate. These findings suggest that the medullary interstitial cells respond to body fluid expansion by CCK release for feedback regulation of the late proximal tubular reabsorption.
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Affiliation(s)
| | - Shunsuke Kimura
- Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kohtarou Konno
- Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Toshihiko Iwanaga
- Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo, Japan
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The Effect of Salt Intake and Potassium Supplementation on Serum Gastrin Levels in Chinese Adults: A Randomized Trial. Nutrients 2017; 9:nu9040389. [PMID: 28420122 PMCID: PMC5409728 DOI: 10.3390/nu9040389] [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] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 03/31/2017] [Accepted: 04/13/2017] [Indexed: 01/01/2023] Open
Abstract
Excess dietary salt is strongly correlated with cardiovascular disease, morbidity, and mortality. Conversely, potassium likely elicits favorable effects against cardiovascular disorders. Gastrin, which is produced by the G-cells of the stomach and duodenum, can increase renal sodium excretion and regulate blood pressure by acting on the cholecystokinin B receptor. The aim of our study was to assess the effects of altered salt and potassium supplementation on serum gastrin levels in humans. A total of 44 subjects (38–65 years old) were selected from a rural community in northern China. All subjects were sequentially maintained on a relatively low-salt diet for 7 days (3.0 g/day of NaCl), a high-salt diet for 7 days (18.0 g/day of NaCl), and then a high-salt diet supplemented with potassium for another 7 days (18.0 g/day of NaCl + 4.5 g/day of KCl). The high-salt intake significantly increased serum gastrin levels (15.3 ± 0.3 vs. 17.6 ± 0.3 pmol/L). This phenomenon was alleviated through potassium supplementation (17.6 ± 0.3 vs. 16.5 ± 0.4 pmol/L). Further analyses revealed that serum gastrin was positively correlated with 24 h urinary sodium excretion (r = 0.476, p < 0.001). By contrast, gastrin level was negatively correlated with blood pressure in all dietary interventions (r = −0.188, p = 0.031). The present study indicated that variations in dietary salt and potassium supplementation affected the serum gastrin concentrations in the Chinese subjects.
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10
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Affiliation(s)
- Jian Yang
- Department of Nutrition, Daping Hospital, The Third Military Medical University, Chongqing, China.,Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Pedro A Jose
- Division of Renal Disease & Hypertension, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China
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11
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Jiang X, Zhang Y, Yang Y, Yang J, Asico LD, Chen W, Felder RA, Armando I, Jose PA, Yang Z. Gastrin stimulates renal dopamine production by increasing the renal tubular uptake of l-DOPA. Am J Physiol Endocrinol Metab 2017; 312:E1-E10. [PMID: 27780818 PMCID: PMC5283882 DOI: 10.1152/ajpendo.00116.2016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 10/18/2016] [Accepted: 10/23/2016] [Indexed: 01/02/2023]
Abstract
Gastrin is a peptide hormone that is involved in the regulation of sodium balance and blood pressure. Dopamine, which is also involved in the regulation of sodium balance and blood pressure, directly or indirectly interacts with other blood pressure-regulating hormones, including gastrin. This study aimed to determine the mechanisms of the interaction between gastrin and dopamine and tested the hypothesis that gastrin produced in the kidney increases renal dopamine production to keep blood pressure within the normal range. We show that in human and mouse renal proximal tubule cells (hRPTCs and mRPTCs, respectively), gastrin stimulates renal dopamine production by increasing the cellular uptake of l-DOPA via the l-type amino acid transporter (LAT) at the plasma membrane. The uptake of l-DOPA in RPTCs from C57Bl/6J mice is lower than in RPTCs from normotensive humans. l-DOPA uptake in renal cortical slices is also lower in salt-sensitive C57Bl/6J than in salt-resistant BALB/c mice. The deficient renal cortical uptake of l-DOPA in C57Bl/6J mice may be due to decreased LAT-1 activity that is related to its decreased expression at the plasma membrane, relative to BALB/c mice. We also show that renal-selective silencing of Gast by the renal subcapsular injection of Gast siRNA in BALB/c mice decreases renal dopamine production and increases blood pressure. These results highlight the importance of renal gastrin in stimulating renal dopamine production, which may give a new perspective in the prevention and treatment of hypertension.
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MESH Headings
- Amino Acid Transport System y+L/drug effects
- Amino Acid Transport System y+L/metabolism
- Animals
- Blood Pressure/drug effects
- Blood Pressure/physiology
- Cells, Cultured
- Dopamine/biosynthesis
- Dopamine/urine
- Down-Regulation
- Gastrins/genetics
- Gastrins/metabolism
- Gastrins/pharmacology
- Gene Silencing
- Humans
- Immunoblotting
- Kidney/drug effects
- Kidney/metabolism
- Kidney Cortex/drug effects
- Kidney Cortex/metabolism
- Kidney Tubules, Proximal/cytology
- Kidney Tubules, Proximal/drug effects
- Kidney Tubules, Proximal/metabolism
- Levodopa/metabolism
- Male
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- RNA, Messenger/drug effects
- RNA, Messenger/metabolism
- RNA, Small Interfering
- Real-Time Polymerase Chain Reaction
- Receptor, Cholecystokinin B/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- Xiaoliang Jiang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical, Beijing, China
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Yanrong Zhang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical, Beijing, China
| | - Yu Yang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland;
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas
| | - Jian Yang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland;
- Department of Cardiology, Daping Hospital, The Third Military Medical University and Chongqing Institute of Cardiology, Chongqing, China
| | - Laureano D Asico
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Wei Chen
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical, Beijing, China
| | - Robin A Felder
- Department of Pathology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Ines Armando
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Pedro A Jose
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
- Department of Medicine, Division of Kidney Disease and Hypertension, The George Washington University School of Medicine and Health Sciences, Washington, DC; and
- Department of Pharmacology and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Zhiwei Yang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical, Beijing, China;
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12
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Affiliation(s)
- Pedro A Jose
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.).
| | - Robin A Felder
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.)
| | - Zhiwei Yang
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.)
| | - Chunyu Zeng
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.)
| | - Gilbert M Eisner
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.)
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Abstract
PURPOSE OF REVIEW Hypertension, which is present in about one quarter of the world's population, is responsible for about 41% of the number one cause of death - cardiovascular disease. Not included in these statistics is the effect of sodium intake on blood pressure, even though an increase or a marked decrease in sodium intake can increase blood pressure. This review deals with the interaction of gut microbiota and the kidney with genetics and epigenetics in the regulation of blood pressure and salt sensitivity. RECENT FINDINGS The abundance of the gut microbes, Firmicutes and Bacteroidetes, is associated with increased blood pressure in several models of hypertension, including the spontaneously hypertensive and Dahl salt-sensitive rats. Decreasing gut microbiota by antibiotics can increase or decrease blood pressure that is influenced by genotype. The biological function of probiotics may also be a consequence of epigenetic modification, related, in part, to microRNA. Products of the fermentation of nutrients by gut microbiota can influence blood pressure by regulating expenditure of energy, intestinal metabolism of catecholamines, and gastrointestinal and renal ion transport, and thus, salt sensitivity. SUMMARY The beneficial or deleterious effect of gut microbiota on blood pressure is a consequence of several variables, including genetics, epigenetics, lifestyle, and intake of antibiotics. These variables may influence the ultimate level of blood pressure and control of hypertension.
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Epstein M, Lifschitz MD. The Unappreciated Role of Extrarenal and Gut Sensors in Modulating Renal Potassium Handling: Implications for Diagnosis of Dyskalemias and Interpreting Clinical Trials. Kidney Int Rep 2016; 1:43-56. [PMID: 29142913 PMCID: PMC5678840 DOI: 10.1016/j.ekir.2016.03.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 03/11/2016] [Indexed: 12/11/2022] Open
Abstract
In addition to the classic and well-established "feedback control" of potassium balance, increasing investigative attention has focused on a novel and not widely recognized complementary regulatory paradigm for maintaining potassium homeostasis-the "feed-forward control" of potassium balance. This regulatory mechanism, initially defined in rumen, has recently been validated in normal human subjects. Studies are being conducted to determine the location for this putative potassium sensor and to evaluate potential signals, which might increase renal potassium excretion. Awareness of this more updated integrative control mechanism for potassium homeostasis is ever more relevant today, when the medical community is increasingly focused on the challenges of managing the hyperkalemia provoked by renin-angiotensin-aldosterone system inhibitors (RAASis). Recent studies have demonstrated a wide gap between RAASi prescribing guidelines and real-world experience and have highlighted that this gap is thought to be attributable in great part to hyperkalemia. Consequently we require a greater knowledge of the complexities of the regulatory mechanisms subserving potassium homeostasis. Sodium polystyrene sulfonate has long been the mainstay for treating hyperkalemia, but its administration is fraught with challenges related to patient discomfort and colonic necrosis. The current and imminent availability of newer potassium binders with better tolerability and more predictive dose-response potassium removal should enhance the management of hyperkalemia. Consequently it is essential to better understand the intricacies of mammalian colonic K+ handling. We discuss colonic transport of K+ and review evidence for potassium (BK) channels being responsible for increased stool K+ in patients with diseases such as ulcerative colitis.
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Affiliation(s)
- Murray Epstein
- Division of Nephrology and Hypertension, University of Miami, Miller School of Medicine, South Florida Veterans Affairs Foundation for Research and Education (SFVAFRE), Miami, Florida, USA
| | - Meyer D. Lifschitz
- Adult Nephrology Unit, Shaare Zedek Medical Center, Jerusalem, Israel
- University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
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15
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Liu T, Konkalmatt PR, Yang Y, Jose PA. Gastrin decreases Na+,K+-ATPase activity via a PI 3-kinase- and PKC-dependent pathway in human renal proximal tubule cells. Am J Physiol Endocrinol Metab 2016; 310:E565-71. [PMID: 26786777 PMCID: PMC4824137 DOI: 10.1152/ajpendo.00360.2015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 01/08/2016] [Indexed: 12/31/2022]
Abstract
The natriuretic effect of gastrin suggests a role in the coordinated regulation of sodium balance by the gastrointestinal tract and the kidney. The renal molecular targets and signal transduction pathways for such an effect of gastrin are largely unknown. Recently, we reported that gastrin induces NHE3 phosphorylation and internalization via phosphatidylinositol (PI) 3-kinase and PKCα. In this study, we show that gastrin induced the phosphorylation of human Na(+),K(+)-ATPase at serine 16, resulting in its endocytosis via Rab5 and Rab7 endosomes. The gastrin-stimulated phosphorylation of Na(+),K(+)-ATPase was dependent on PI 3-kinase because the phosphorylation was blocked by the PI 3-kinase inhibitor wortmannin. The phosphorylation of Na(+),K(+)-ATPase was also blocked by chelerythrine, a pan-PKC inhibitor, Gö-6976, a conventional PKC (cPKC) inhibitor, and BAPTA-AM, an intracellular calcium chelator, suggesting the importance of cPKC and intracellular calcium in the gastrin signaling pathway. The gastrin-mediated phosphorylation of Na(+),K(+)-ATPase was also inhibited by U-73122, a phospholipase C (PLC) inhibitor. These results suggest that gastrin regulates sodium hydrogen exchanger and pump in renal proximal tubule cells at the apical and basolateral membranes.
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Affiliation(s)
- Tianbing Liu
- Center for Molecular Physiology Research, Children's Research Institute, Children's National Medical Center, Washington, DC
| | - Prasad R Konkalmatt
- Departments of Medicine and Physiology, University of Maryland School of Medicine, Baltimore, Maryland; Division of Renal Diseases and Hypertension, Department of Medicine, George Washington University School of Medicine and Health Sciences, Washington, DC; and
| | - Yu Yang
- Center for Molecular Physiology Research, Children's Research Institute, Children's National Medical Center, Washington, DC; Departments of Medicine and Physiology, University of Maryland School of Medicine, Baltimore, Maryland
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16
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Jose PA, Yang Z, Zeng C, Felder RA. The importance of the gastrorenal axis in the control of body sodium homeostasis. Exp Physiol 2016; 101:465-70. [PMID: 26854262 DOI: 10.1113/ep085286] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 02/01/2016] [Indexed: 12/27/2022]
Abstract
NEW FINDINGS What is the topic of this review? Sensing the amount of ingested sodium is one mechanism by which sodium balance is regulated. This review describes the role of gastrin in the cross-talk between the stomach and the kidney following the ingestion of sodium. What advances does it highlight? Neural mechanisms and several gut hormones, including cholecystokinin and uroguanylin, have been suggested to mediate the natriuresis after an oral sodium load. It is proposed that gastrin produced by G-cells via its receptor, cholecystokinin B receptor, interacts with renal D1 -like dopamine receptors to increase renal sodium excretion. Hypertension develops with chronically increased sodium intake when sodium that accumulates in the body can no longer be sequestered, extracellular fluid volume is expanded, and compensatory neural, hormonal and pressure-natriuresis mechanisms fail. Sensing the amount of ingested sodium, by the stomach, is one mechanism by which sodium balance is regulated. The natriuresis following the ingestion of a certain amount of sodium may be due to an enterokine, gastrin, secreted by G-cells in the stomach and duodenum and released into the circulation. Circulating gastrin levels are 10- to 20-fold higher than those for cholecystokinin. Of all the gut hormones circulating in the plasma, gastrin is the one that is reabsorbed to the greatest extent by renal tubules. Gastrin, via its receptor, the cholecystokinin type B receptor (CCKBR), is natriuretic in mammals, including humans, by inhibition of renal sodium transport. Germline deletion of gastrin (Gast) or Cckbr gene in mice causes salt-sensitive hypertension. Selective silencing of Gast in the stomach and duodenum impairs the ability to excrete an oral sodium load and also increases blood pressure. Thus, the gastrorenal axis, mediated by gastrin, can complement pronatriuretic hormones, such as dopamine, to increase sodium excretion after an oral sodium load. These studies in mice may be translatable to humans because the chromosomal loci of CCKBR and GAST are linked to human essential hypertension. Understanding the role of genes in the regulation of renal function and blood pressure may lead to the tailoring of antihypertensive treatment based on genetic make-up.
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Affiliation(s)
- Pedro A Jose
- Department of Medicine, The George Washington University School of Medicine, Washington, DC, USA.,Department of Physiology, The George Washington University School of Medicine, Washington, DC, USA
| | - Zhiwei Yang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences & Comparative Medicine Centre, Peking Union Medical College, Beijing, PR China
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing 400042, PR China
| | - Robin A Felder
- Department of Pathology, The University of Virginia, Charlottesville, VA, USA
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17
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Jiang X, Chen W, Liu X, Wang Z, Liu Y, Felder RA, Gildea JJ, Jose PA, Qin C, Yang Z. The Synergistic Roles of Cholecystokinin B and Dopamine D5 Receptors on the Regulation of Renal Sodium Excretion. PLoS One 2016; 11:e0146641. [PMID: 26751218 PMCID: PMC4709046 DOI: 10.1371/journal.pone.0146641] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 12/21/2015] [Indexed: 01/07/2023] Open
Abstract
Renal dopamine D1-like receptors (D1R and D5R) and the gastrin receptor (CCKBR) are involved in the maintenance of sodium homeostasis. The D1R has been found to interact synergistically with CCKBR in renal proximal tubule (RPT) cells to promote natriuresis and diuresis. D5R, which has a higher affinity for dopamine than D1R, has some constitutive activity. Hence, we sought to investigate the interaction between D5R and CCKBR in the regulation of renal sodium excretion. In present study, we found D5R and CCKBR increase each other’s expression in a concentration- and time-dependent manner in the HK-2 cell, the specificity of which was verified in HEK293 cells heterologously expressing both human D5R and CCKBR and in RPT cells from a male normotensive human. The specificity of D5R in the D5R and CCKBR interaction was verified further using a selective D5R antagonist, LE-PM436. Also, D5R and CCKBR colocalize and co-immunoprecipitate in BALB/c mouse RPTs and human RPT cells. CCKBR protein expression in plasma membrane-enriched fractions of renal cortex (PMFs) is greater in D5R-/- mice than D5R+/+ littermates and D5R protein expression in PMFs is also greater in CCKBR-/- mice than CCKBR+/+ littermates. High salt diet, relative to normal salt diet, increased the expression of CCKBR and D5R proteins in PMFs. Disruption of CCKBR in mice caused hypertension and decreased sodium excretion. The natriuresis in salt-loaded BALB/c mice was decreased by YF476, a CCKBR antagonist and Sch23390, a D1R/D5R antagonist. Furthermore, the natriuresis caused by gastrin was blocked by Sch23390 while the natriuresis caused by fenoldopam, a D1R/D5R agonist, was blocked by YF476. Taken together, our findings indicate that CCKBR and D5R synergistically interact in the kidney, which may contribute to the maintenance of normal sodium balance following an increase in sodium intake.
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Affiliation(s)
- Xiaoliang Jiang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Wei Chen
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Xing Liu
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Zihao Wang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Yunpeng Liu
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
| | - Robin A. Felder
- Department of Pathology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - John J. Gildea
- Department of Pathology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Pedro A. Jose
- Division of Nephrology, Departments of Medicine and Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (PAJ); (CQ); (ZWY)
| | - Chuan Qin
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
- * E-mail: (PAJ); (CQ); (ZWY)
| | - Zhiwei Yang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) & Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China
- CollaborativeInnovation Center for Cardiovascular Disorders, Beijing, P. R. China
- * E-mail: (PAJ); (CQ); (ZWY)
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18
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Faridi MS, Jaiswal MSD, Goel SK. Expression of CCK Receptors in Carcinoma Gallbladder and Cholelithiasis: A Pilot Study. J Clin Diagn Res 2015; 9:PC04-7. [PMID: 26393162 PMCID: PMC4572993 DOI: 10.7860/jcdr/2015/12697.6152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Accepted: 05/07/2015] [Indexed: 12/16/2022]
Abstract
BACKGROUND Gastrin and cholecystokinin (CCK) receptors are trophic for various gastrointestinal malignancies. Their role in gallbladder cancer has not been widely studied. OBJECTIVES To identify expression of CCK-A and CCK-B receptors in the tissue and blood of patients suffering from carcinoma (CA) gallbladder and gallstone disease and to compare expression of CCK A and B receptors in the gall bladder tissue and blood of healthy individuals and patients of CA gallbladder, and gallstone diseases. MATERIALS AND METHODS Forty nine subjects of both genders were recruited, comprising of 22 patients of CA gall bladder, 19 cases of cholelithiasis and, 8 normal gallbladders obtained from patients operated for trauma of the biliary system or Whipple's procedure. RNA extraction and cDNA formation for CCK-A and CCK-B receptors were carried out. Real Time PCR was performed on cDNA and threshold cycle (Ct) value of each sample was obtained and ΔCt was calculated. Chi-square test for comparing two groups and ANOVA test for comparing multiple groups were applied and if p<0.05 then Dunnett-C test was performed. OBSERVATION AND RESULTS Both CCK-A and CCK-B receptors were expressed irrespective of its origin in all tissues and blood samples studied; be it normal, Cholelithiasis or CA gallbladder and there was no difference among them (p>0.05). CONCLUSION This preliminary study showed higher expression of CCK-A receptors in patients of cholelithiasis and decreased expression of CCK-A receptors in patients of CA gallbladder as compared to normal gallbladder although it did not rise to statistical significance.
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Affiliation(s)
- Mohammad Shazib Faridi
- Trainee, Department of Urology,Presently at Regional Institute of Medical Sciences, Imphal, Manipur, India
| | | | - Sudhir K. Goel
- Scientist, Petroleum Toxicology Division,Indian Institute of Toxicology Research, Lucknow, U.P, India
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19
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Chen Y, Asico LD, Zheng S, Villar VAM, He D, Zhou L, Zeng C, Jose PA. Gastrin and D1 dopamine receptor interact to induce natriuresis and diuresis. Hypertension 2013; 62:927-33. [PMID: 24019399 DOI: 10.1161/hypertensionaha.113.01094] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Oral NaCl produces a greater natriuresis and diuresis than the intravenous infusion of the same amount of NaCl. Gastrin is the major gastrointestinal hormone taken up by renal proximal tubule (RPT) cells. We hypothesized that renal gastrin and dopamine receptors interact to synergistically increase sodium excretion, an impaired interaction of which may be involved in the pathogenesis of hypertension. In Wistar-Kyoto rats, infusion of gastrin induced natriuresis and diuresis, which was abrogated in the presence of a gastrin (cholecystokinin B receptor [CCKBR]; CI-988) or a D1-like receptor antagonist (SCH23390). Similarly, the natriuretic and diuretic effects of fenoldopam, a D1-like receptor agonist, were blocked by SCH23390, as well as by CI-988. However, the natriuretic effects of gastrin and fenoldopam were not observed in spontaneously hypertensive rats. The gastrin/D1-like receptor interaction was also confirmed in RPT cells. In RPT cells from Wistar-Kyoto but not spontaneously hypertensive rats, stimulation of either D1-like receptor or gastrin receptor inhibited Na(+)-K(+)-ATPase activity, an effect that was blocked in the presence of SCH23390 or CI-988. In RPT cells from Wistar-Kyoto and spontaneously hypertensive rats, CCKBR and D1 receptor coimmunoprecipitated, which was increased after stimulation of either D1 receptor or CCKBR in RPT cells from Wistar-Kyoto rats; stimulation of one receptor increased the RPT cell membrane expression of the other receptor, effects that were not observed in spontaneously hypertensive rats. These data suggest that there is a synergism between CCKBR and D1-like receptors to increase sodium excretion. An aberrant interaction between the renal CCK BR and D1-like receptors (eg, D1 receptor) may play a role in the pathogenesis of hypertension.
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Affiliation(s)
- Yue Chen
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing 400042, China.
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20
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Liu T, Jose PA. Gastrin induces sodium-hydrogen exchanger 3 phosphorylation and mTOR activation via a phosphoinositide 3-kinase-/protein kinase C-dependent but AKT-independent pathway in renal proximal tubule cells derived from a normotensive male human. Endocrinology 2013; 154:865-75. [PMID: 23275470 PMCID: PMC3548178 DOI: 10.1210/en.2012-1813] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Gastrin is natriuretic, but its renal molecular targets and signal transduction pathways are not fully known. In this study, we confirmed the existence of CCKBR (a gastrin receptor) in male human renal proximal tubule cells and discovered that gastrin induced S6 phosphorylation, a downstream component of the phosphatidylinositol 3 kinase (PI3 kinase)-mammalian target of rapamycin pathway. Gastrin also increased the phosphorylation of sodium-hydrogen exchanger 3 (NHE3) at serine 552, caused its internalization, and decreased its expression at the cell surface and NHE activity. The phosphorylation of NHE3 and S6 was dependent on PI3 kinases because it was blocked by 2 different PI3-kinase inhibitors, wortmannin and LY294,002. The phosphorylation of NHE3 and S6 was not affected by the protein kinase A inhibitor H-89 but was blocked by a pan-PKC (chelerythrine) and a conventional PKC (cPKC) inhibitor (Gö6976) (10 μM) and an intracellular calcium chelator, 1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid, tetra(acetoxymethyl)-ester, suggesting the importance of cPKC and intracellular calcium in the gastrin signaling pathway. The cPKC involved was probably PKCα because it was phosphorylated by gastrin. The gastrin-mediated phosphorylation of NHE3, S6, and PKCα was via phospholipase C because it was blocked by a phospholipase C inhibitor, U73122 (10 μM). The phosphorylation (activation) of AKT, which is usually upstream of mammalian target of rapamycin in the classic PI3 kinase-AKT-p70S6K signaling pathway, was not affected, suggesting that the gastrin-induced phosphorylation of NHE3 and S6 is dependent on both PI3 kinase and PKCα but not AKT.
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Affiliation(s)
- Tianbing Liu
- Center for Molecular Physiology Research, Children's Research Institute, Children's National Medical Center, 111 Michigan Avenue, Washington, DC 20010, USA.
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21
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The Role of Cholecystokinin Receptors in the Short-Term Control of Food Intake. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 114:277-316. [DOI: 10.1016/b978-0-12-386933-3.00008-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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22
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Jiang X, Wang W, Ning B, Liu X, Gong J, Gan F, Gao X, Zhang L, Jose PA, Qin C, Yang Z. Basal and postprandial serum levels of gastrin in normotensive and hypertensive adults. Clin Exp Hypertens 2012; 35:74-8. [PMID: 22680232 DOI: 10.3109/10641963.2012.690474] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Gastrin is a peptide hormone, which acts not only to regulate gastric acid secretion, but also to exert physiological actions such as the regulation of sodium balance. From a case (n = 95)-control (n = 82) study in Fuyang People's Hospital, Anhui Province, China, we found that the fasting serum gastrin levels are similar in normotensive and hypertensive adults but increased to higher levels in the latter group than in the former group after a mixed meal. We suggest that gastrin is involved in the regulation of blood pressure, possibly via the regulation of sodium and water metabolism and/or renin-angiotensin-aldosterone system. However, the mechanism remains to be determined.
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Affiliation(s)
- Xiaoliang Jiang
- Key Laboratory of Human Diseases Comparative Medicine, Ministry of Health, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences & Comparative Medicine Centre, Peking Union Medical College, Beijing, PR China
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23
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Miyamoto S, Shikata K, Miyasaka K, Okada S, Sasaki M, Kodera R, Hirota D, Kajitani N, Takatsuka T, Kataoka HU, Nishishita S, Sato C, Funakoshi A, Nishimori H, Uchida HA, Ogawa D, Makino H. Cholecystokinin plays a novel protective role in diabetic kidney through anti-inflammatory actions on macrophage: anti-inflammatory effect of cholecystokinin. Diabetes 2012; 61:897-907. [PMID: 22357963 PMCID: PMC3314350 DOI: 10.2337/db11-0402] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Inflammatory process is involved in the pathogenesis of diabetic nephropathy. In this article, we show that cholecystokinin (CCK) is expressed in the kidney and exerts renoprotective effects through its anti-inflammatory actions. DNA microarray showed that CCK was upregulated in the kidney of diabetic wild-type (WT) mice but not in diabetic intracellular adhesion molecule-1 knockout mice. We induced diabetes in CCK-1 receptor (CCK-1R) and CCK-2R double-knockout (CCK-1R(-/-),-2R(-/-)) mice, and furthermore, we performed a bone marrow transplantation study using CCK-1R(-/-) mice to determine the role of CCK-1R on macrophages in the diabetic kidney. Diabetic CCK-1R(-/-),-2R(-/-) mice revealed enhanced albuminuria and inflammation in the kidney compared with diabetic WT mice. In addition, diabetic WT mice with CCK-1R(-/-) bone marrow-derived cells developed more albuminuria than diabetic CCK-1R(-/-) mice with WT bone marrow-derived cells. Administration of sulfated cholecystokinin octapeptide (CCK-8S) ameliorated albuminuria, podocyte loss, expression of proinflammatory genes, and infiltration of macrophages in the kidneys of diabetic rats. Furthermore, CCK-8S inhibited both expression of tumor necrosis factor-α and chemotaxis in cultured THP-1 cells. These results suggest that CCK suppresses the activation of macrophage and expression of proinflammatory genes in diabetic kidney. Our findings may provide a novel strategy of therapy for the early stage of diabetic nephropathy.
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Affiliation(s)
- Satoshi Miyamoto
- Department of Medicine and Clinical Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
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Desai AJ, Miller LJ. Sensitivity of cholecystokinin receptors to membrane cholesterol content. Front Endocrinol (Lausanne) 2012; 3:123. [PMID: 23087674 PMCID: PMC3475150 DOI: 10.3389/fendo.2012.00123] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2012] [Accepted: 10/01/2012] [Indexed: 12/18/2022] Open
Abstract
Cholesterol represents a structurally and functionally important component of the eukaryotic cell membrane, where it increases lipid order, affects permeability, and influences the lateral mobility and conformation of membrane proteins. Several G protein-coupled receptors have been shown to be affected by the cholesterol content of the membrane, with functional impact on their ligand binding and signal transduction characteristics. The effects of cholesterol can be mediated directly by specific molecular interactions with the receptor and/or indirectly by altering the physical properties of the membrane. This review focuses on the importance and differential effects of membrane cholesterol on the activity of cholecystokinin (CCK) receptors. The type 1 CCK receptor is quite sensitive to its cholesterol environment, while the type 2 CCK receptor is not. The possible structural basis for this differential impact is explored and the implications of pathological states, such as metabolic syndrome, in which membrane cholesterol may be increased and CCK1R function may be abnormal are discussed. This is believed to have substantial potential importance for the development of drugs targeting the CCK receptor.
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Affiliation(s)
| | - Laurence J. Miller
- *Correspondence: Laurence J. Miller, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, 13400 E. Shea Blvd., Scottsdale, AZ 85259, USA. e-mail:
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Abstract
The aim of the present review is to synthesise and summarise our recent knowledge on the involvement of cholecystokinin (CCK) and gastrin peptides and their receptors in the control of digestive functions and more generally their role in the field of nutrition in mammals. First, we examined the release of these peptides from the gut, focusing on their molecular forms, the factors regulating their release and the signalling pathways mediating their effects. Second, general physiological effects of CCK and gastrin peptides are described with regard to their specific receptors and the role of CCK on vagal mucosal afferent nerve activities. Local effects of CCK and gastrin in the gut are also reported, including gut development, gastrointestinal motility and control of pancreatic functions through vagal afferent pathways, including NO. Third, some examples of the intervention of the CCK and gastrin peptides are exposed in diseases, taking into account intervention of the classical receptor subtypes (CCK1 and CCK2 receptors) and their heterodimerisation as well as CCK-C receptor subtype. Finally, applications and future challenges are suggested in the nutritional field (performances) and in therapy with regards to the molecular forms or in relation with the type of receptor as well as new techniques to be utilised in detection or in therapy of disease. In conclusion, the present review underlines recent developments in this field: CCK and gastrin peptides and their receptors are the key factor of nutritional aspects; a better understanding of the mechanisms involved may increase the efficiency of the nutritional functions and the treatment of abnormalities under pathological conditions.
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26
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Aunapuu M, Roosaar P, Järveots T, Kurrikoff K, Kõks S, Vasar E, Arend A. Altered renal morphology in transgenic mice with cholecystokinin overexpression. Transgenic Res 2008; 17:1079-89. [DOI: 10.1007/s11248-008-9204-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Accepted: 07/07/2008] [Indexed: 01/15/2023]
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Michell A, Debnam E, Unwin R. Regulation of Renal Function by the Gastrointestinal Tract: Potential Role of Gut-Derived Peptides and Hormones. Annu Rev Physiol 2008; 70:379-403. [DOI: 10.1146/annurev.physiol.69.040705.141330] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- A.R. Michell
- Department of Biochemical Pharmacology, William Harvey Research Institute, St. Bartholomew's Hospital Medical School, London EC1M 6BQ, United Kingdom;
| | - E.S. Debnam
- Department of Physiology, Royal Free and University College Medical School, London NW3 2PF, United Kingdom;
| | - R.J. Unwin
- Department of Physiology, Royal Free and University College Medical School, London NW3 2PF, United Kingdom;
- Centre for Nephrology, Royal Free and University College Medical School, London NW3 2PF, United Kingdom;
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28
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Abstract
Cholecystokinin and gastrin receptors (CCK1R and CCK2R) are G protein-coupled receptors that have been the subject of intensive research in the last 10 years with corresponding advances in the understanding of their functioning and physiology. In this review, we first describe general properties of the receptors, such as the different signaling pathways used to exert short- and long-term effects and the structural data that explain their binding properties, activation, and regulation. We then focus on peripheral cholecystokinin receptors by describing their tissue distribution and physiological actions. Finally, pathophysiological peripheral actions of cholecystokinin receptors and their relevance in clinical disorders are reviewed.
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Affiliation(s)
- Marlène Dufresne
- Institut National de la Santé et de la Recherche Médicale U. 531, Institut Louis Bugnard, Centre Hospitalier Universitaire Rangueil, France
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29
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Pisarchik A, Wortsman J, Slominski A. A novel microarray to evaluate stress-related genes in skin: effect of ultraviolet light radiation. Gene 2004; 341:199-207. [PMID: 15474302 DOI: 10.1016/j.gene.2004.06.046] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2004] [Revised: 06/08/2004] [Accepted: 06/21/2004] [Indexed: 11/25/2022]
Abstract
We tested transcriptional responses to ultraviolet radiation in epidermal keratinocytes using microarray chips containing more than 700 neuroendocrine-immune-related genes. The gene expression pattern was nonrandom and time-dependent; it included increased expression of genes involved in water and salt balance, prostaglandin synthesis, keratinocyte differentiation as well as genes coding for stress effectors, cytokines and metalloproteinases (MMPs). In contrast, expression was decreased for genes coding for growth factors and their receptors and for elements of extracellular matrix. This pattern suggests that transcriptional responses are coordinated and aimed at the preservation of epidermal barrier function, prevention of early carcinogenic events and remodeling of extracellular matrix. In summary, we have developed a microarray chip that can be used for simultaneous testing of transcriptional responses to cutaneous stressors in the context of neuroendocrine-immune functions of the skin.
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Affiliation(s)
- Alexander Pisarchik
- Department of Pathology and Laboratory Medicine, Room 519, University of Tennessee Health Science Center, 930 Madison Ave., Memphis, TN 38163, USA
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30
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Dumesny C, Whitley JC, Baldwin GS, Giraud AS, Shulkes A. Developmental expression and biological activity of gastrin-releasing peptide and its receptors in the kidney. Am J Physiol Renal Physiol 2004; 287:F578-85. [PMID: 15140764 DOI: 10.1152/ajprenal.00416.2003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mammalian gastrin-releasing peptide (GRP) has a widespread distribution and multiple stimulating effects on metabolism, release of regulatory peptides, gastrointestinal and pancreatic secretions, and behavior. GRP is a potent mitogen for a number of tumor types, including colon and lung. Although GRP is known to stimulate the growth of renal tumors, little is known of its synthesis, distribution, and receptors in the developing and mature kidney. Both Northern blot analysis and RT-PCR revealed the presence of GRP mRNA in ovine kidney from midgestation through to adulthood. GRP mRNA was detected in rat kidney from embryonic day 19 to postnatal day 30 by RT-PCR. Sequence-specific radioimmunoassay demonstrated the presence of substantial amounts of fully processed amidated GRP in the ovine renal cortex and medulla. The mRNA for the major receptor subtype, GRP-R, was present in fetal and adult sheep and rat kidneys. The mRNA for the low-affinity GRP receptor, bombesin receptor subtype-3 (BRS-3), was only detected in the rat kidney. In the ovine kidney, immunohistochemistry localized GRP predominantly to the thick ascending limb of the loop of Henle. mRNAs for GRP, GRP-R, and BRS-3 were detected in the human embryonic kidney cell line HEK293, and radioimmunoassay of cell extracts and conditioned media revealed the presence of proGRP but not the amidated form. However, amidated GRP did stimulate the proliferation of these cells. These studies demonstrate that the developing and mature kidney may be previously unidentified sites of autocrine or paracrine action for GRP.
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Affiliation(s)
- Chelsea Dumesny
- University of Melbourne Department of Surgery, Austin Hospital, Melbourne, Victoria 3084, Australia
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31
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Bläker M, Arrenberg P, Stange I, Schulz M, Burghardt S, Michaelis H, Pace A, Greten H, von Schrenck T, de Weerth A. The cholecystokinin2-receptor mediates calcitonin secretion, gene expression, and proliferation in the human medullary thyroid carcinoma cell line, TT. ACTA ACUST UNITED AC 2004; 118:111-7. [PMID: 14759564 DOI: 10.1016/j.regpep.2003.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2003] [Revised: 11/26/2003] [Accepted: 11/28/2003] [Indexed: 10/26/2022]
Abstract
Gastrin-induced release of calcitonin from medullary thyroid carcinomas (MTC) is based on the expression of the cholecystokinin(2)-receptor (CCK(2)R) in these tumors. Recently, we have shown that the CCK(2)R is expressed not only in MTC but also in C-cells within the normal thyroid gland. The functions of the CCK(2)R in MTC and C-cells are largely unknown. We therefore explored the effects of gastrin-induced CCK(2)R stimulation in the highly differentiated MTC cell line, TT. CCK(2)R expression in TT-cells is detectable by RT-PCR as well as immunocytochemistry. Stimulation of the CCK(2)R by gastrin induces immediate release of calcitonin from TT-cells. Moreover, quantitative (LightCycler) RT-PCR demonstrates that gastrin stimulates transcription of the calcitonin and chromogranin A genes in TT-cells. TT-cell proliferation, assessed by counting of viable cells and (3)H-thymidine uptake, is markedly increased by gastrin. This effect is inhibited by the CCK(2)R-specific antagonist L-365,260. Our findings suggest physiological functions for the CCK(2)R in calcitonin-secretion and gene expression as well as a pathophysiological role in MTC proliferation. CCK(2)R antagonists might have therapeutic potential in these tumors.
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Affiliation(s)
- Michael Bläker
- Medizinische Klinik I, Zentrum für Innere Medizin, Universitätsklinikum Hamburg-Eppendorf, Martinistrabetae 52, 20246 Hamburg, Germany.
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32
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Abstract
Gastrin is a peptide hormone that regulates both acid secretion and growth of the gastric oxyntic mucosa. Recent studies suggest that gastrin, in both its amidated, and less processed forms (glycine-extended gastrin and progastrin) may also exert biological activity in other organs in the gastrointestinal tract. This article will review the studies performed to date addressing the physiological role of gastrin outside of the gastric mucosa, with particular emphasis on the information gleaned from gastrin-deficient mice. Most of these studies address the potential role for the less processed forms of gastrin in regulating the proliferation of the colonic mucosa and colon cancers. There is also some data to support a potential role for gastrin in the regulation of the pancreas and the kidney, although the effects of gastrin deficiency on the function of these organs in mice have not yet been rigorously studied.
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Affiliation(s)
- Theodore J Koh
- University of Massachusetts Memorial Medical Center, Worcester, MA 01605, USA.
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Fourmy D, Escrieut C, Archer E, Galès C, Gigoux V, Maigret B, Moroder L, Silvente-Poirot S, Martinez J, Fehrentz JA, Pradayrol L. Structure of cholecystokinin receptor binding sites and mechanism of activation/inactivation by agonists/antagonists. PHARMACOLOGY & TOXICOLOGY 2002; 91:313-20. [PMID: 12688374 DOI: 10.1034/j.1600-0773.2002.910608.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Delineation of CCK receptor binding sites is a prerequisite for the understanding of the molecular basis for ligand recognition, partial agonism, ligand-induced traffiking of receptor signalling. In the current paper, we illustrate how, in the past 5 years, studies from our laboratory and others have provided new data on the molecular basis of the pharmacology and functioning of CCK1 and CCK2 receptors. Available data on CCK1 and CCK2R binding sites indicate that 1) homologous regions of the two receptors are involved in the binding site of CCK, however, positioning of CCK slightly differs; 2) binding sites of non-peptide agonists/antagonist are buried in the pocket formed by transmembrane helices and overlap that of CCK and 3) residues of the binding sites as well as of conserved motifs such as E/DRY, NPXXY are crucial for receptor activation.
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Affiliation(s)
- Daniel Fourmy
- INSERM U 531, Louis Bugnard Institute, CHU Rangueil, Bat. L3, 31403 Toulouse Cedex 4, France.
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