1
|
Mardones O, Oyarzún-Salazar R, Labbé BS, Miguez JM, Vargas-Chacoff L, Muñoz JLP. Intestinal variation of serotonin, melatonin, and digestive enzymes activities along food passage time through GIT in Salmo salar fed with supplemented diets with tryptophan and melatonin. Comp Biochem Physiol A Mol Integr Physiol 2022; 266:111159. [PMID: 35114387 DOI: 10.1016/j.cbpa.2022.111159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 01/26/2022] [Accepted: 01/27/2022] [Indexed: 12/22/2022]
Abstract
In teleosts, peripheral serotonin (5-HT) and melatonin (MEL) are synthesised in the gastrointestinal tract (GIT) and regulate secretion and motility processes. Their production is regulated by diet and the passage of food through the GIT. This study aimed to evaluate how intestinal 5-HT, melatonin, and the activity of digestive enzymes varied with food passage time through GIT in Atlantic salmon (Salmo salar). We fed fish diets supplemented with tryptophan and melatonin (L-Trp 2.5% and MEL 0.01%) and measured the activity of digestive enzymes (amylase, lipase, and total protease) in the pyloric caeca, midgut, and hindgut at different times after feeding. 5-HT levels increased in all GIT portions and diets at 120 min post-intake and were highest in the pyloric caeca. Intestinal enzymatic activity was varied with diet, post-intake time and in different intestinal portions. In conclusion, food passage time directly affects GIT 5-HT secretion and digestive enzyme activity in S. salar, and diet composition regulates S. salar GIT function.
Collapse
Affiliation(s)
- O Mardones
- Centro de Investigación y Desarrollo i~mar, Universidad de los Lagos, Puerto Montt, Chile
| | - R Oyarzún-Salazar
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile; Centro Fondap-IDEAL, Universidad Austral de Chile, Valdivia, Chile
| | - B S Labbé
- Centro de Investigación y Desarrollo i~mar, Universidad de los Lagos, Puerto Montt, Chile; Programa de Magister en Ciencias, mención manejo, Producción, Manejo y Conservación de Recursos Naturales, Universidad de Los Lagos, Puerto Montt, Chile
| | - J M Miguez
- Laboratorio de Fisiología de Peces, Facultad de Biología, Universidade Vigo, Vigo, Spain
| | - L Vargas-Chacoff
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile; Centro Fondap-IDEAL, Universidad Austral de Chile, Valdivia, Chile; Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems, BASE, University Austral of Chile, Valdivia, Chile.
| | - J L P Muñoz
- Centro de Investigación y Desarrollo i~mar, Universidad de los Lagos, Puerto Montt, Chile.
| |
Collapse
|
2
|
Estaras M, Peña FJ, Tapia JA, Fernandez-Bermejo M, Mateos JM, Vara D, Roncero V, Blanco G, Lopez D, Salido GM, Gonzalez A. Melatonin modulates proliferation of pancreatic stellate cells through caspase-3 activation and changes in cyclin A and D expression. J Physiol Biochem 2020; 76:345-355. [PMID: 32361979 DOI: 10.1007/s13105-020-00740-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 04/17/2020] [Indexed: 12/12/2022]
Abstract
In this study, the effects of melatonin (1 μM-1 mM) on pancreatic stellate cells (PSC) have been examined. Cell viability and proliferation, caspase-3 activation, and the expression of cyclin A and cyclin D were analyzed. Our results show that melatonin decreased PSC viability in a time- and concentration-dependent manner. This effect was not inhibited by treatment of cells with MT1, MT2, calmodulin, or ROR-alpha inhibitors prior to melatonin addition. Activation of caspase-3 in response to melatonin was detected. The expression of cyclin A and cyclin D was decreased in cells treated with melatonin. Finally, changes in BrdU incorporation into the newly synthesized DNA of proliferating cells were also observed in the presence of melatonin. We conclude that melatonin, at pharmacological concentrations, modulates proliferation of PSC through activation of apoptosis and involving crucial regulators of the cell cycle. These actions might not require specific melatonin receptors. Our observations suggest that melatonin, at high doses, could potentially exert anti-fibrotic effects and, thus, could be taken into consideration as supportive treatment in the therapy of pancreatic diseases.
Collapse
Affiliation(s)
- Matias Estaras
- Institute of Molecular Pathology Biomarkers, University of Extremadura, Avenida de las Ciencias s/n, E-10003, Cáceres, Spain
| | - Fernando J Peña
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - José A Tapia
- Institute of Molecular Pathology Biomarkers, University of Extremadura, Avenida de las Ciencias s/n, E-10003, Cáceres, Spain
| | | | - Jose M Mateos
- Department of Gastroenterology, San Pedro de Alcantara Hospital, Cáceres, Spain
| | - Daniel Vara
- Department of Gastroenterology, San Pedro de Alcantara Hospital, Cáceres, Spain
| | - Vicente Roncero
- Unit of Histology and Pathological Anatomy, Veterinary Faculty, University of Extremadura, Cáceres, Spain
| | - Gerardo Blanco
- Hepatobiliary-Pancreatic Surgery and Liver Transplant Unit, Infanta Cristina Hospital, Badajoz, Spain
| | - Diego Lopez
- Hepatobiliary-Pancreatic Surgery and Liver Transplant Unit, Infanta Cristina Hospital, Badajoz, Spain
| | - Gines M Salido
- Institute of Molecular Pathology Biomarkers, University of Extremadura, Avenida de las Ciencias s/n, E-10003, Cáceres, Spain
| | - Antonio Gonzalez
- Institute of Molecular Pathology Biomarkers, University of Extremadura, Avenida de las Ciencias s/n, E-10003, Cáceres, Spain.
| |
Collapse
|
3
|
Effect of Dietary Rumen-Protected L-Tryptophan Supplementation on Growth Performance, Blood Hematological and Biochemical Profiles, and Gene Expression in Korean Native Steers under Cold Environment. Animals (Basel) 2019; 9:ani9121036. [PMID: 31783557 PMCID: PMC6941001 DOI: 10.3390/ani9121036] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 11/22/2019] [Accepted: 11/22/2019] [Indexed: 01/06/2023] Open
Abstract
Simple Summary In this study, the effect of dietary rumen-protected L-tryptophan (RPT) supplement on growth performance, blood hematological and biochemical profiles, and gene expression was investigated in beef steers during a cold environment. We revealed that supplementation of 0.1% RPT incorporated into diet was beneficial owing to enhanced growth performance by increasing the ADG and glucose level, decreasing the feed conversion ratio, and maintaining homeostasis in immune responses in beef steers in a cold environment. Abstract We assessed the growth performance, physiological traits, and gene expressions in steers fed with dietary rumen-protected L-tryptophan (RPT) under a cold environment. Eight Korean native steers were assigned to two dietary groups, no RPT (Control) and RPT (0.1% RPT supplementation on a dry matter basis) for six weeks. Maximum and minimum temperatures throughout the experiment were 6.7 °C and −7.0 °C, respectively. Supplementation of 0.1% RPT to a total mixed ration did not increase body weight but had positive effects of elevating average daily gain (ADG) and reducing the feed conversion ratio (FCR) on days 27 and 48. The metabolic parameter showed a higher glucose level (on day 27) in the 0.1% RPT group compared to the control group. Real-time PCR analysis showed no significant differences in the expression of muscle (MYF6, MyoD, and Desmin) metabolism genes between the two groups, whereas the expression of fat (PPARγ, C/EBPα, and FABP4) metabolism genes was lower in the 0.1% RPT group than in the control group. Thus, we demonstrate that long-term (six weeks) dietary supplementation of 0.1% RPT was beneficial owing to enhanced growth performance by increasing the ADG and glucose level, decreasing FCR, and maintaining homeostasis in immune responses in beef steers in a cold environment.
Collapse
|
4
|
Venugopal SP. Effect of melatonin on the onset of puberty in male juvenile rats. Anat Cell Biol 2019; 52:286-295. [PMID: 31598358 PMCID: PMC6773899 DOI: 10.5115/acb.18.122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 12/18/2018] [Accepted: 02/22/2019] [Indexed: 11/27/2022] Open
Abstract
Melatonin or N-acetyl-5-methoxytryptamine, the fascinating molecule secreted by the pineal gland. Melatonin has a close interaction with hypothalamic-pituitary-gonadal axis. In non-seasonal breeders like rat its exact role in reproduction is controvertible. So it is worth to explore the possible role of melatonin on the onset of puberty in male albino rats. Two groups of male rats aged 5 and 10 days were used for the study. In each group, there were three subgroups, each receiving melatonin for 5 days, 10 days or till the day of descent of testes. Similar subgroups were used as controls. Without handling, animals were observed daily for the onset of puberty. On the day of descent of testes, body weight of the animal was noted, blood was collected, serum was separated and used for radio immunoassay. For histomorphometric analysis, all morphometric measurements were done using an occular micrometer. Volume fraction of seminiferous tubules, intertubular connective tissue of testes, cortex and medulla of thymus were estimated by point count method. In both the age groups melatonin advanced the age on descent of testes, increased the body weight, organ weight. It also increased the serum hormone levels. So, in conclusion this study indicates that exogenous melatonin advances the onset of puberty in male albino wistar rats and this effect is more pronounced in the younger animals.
Collapse
|
5
|
Estaras M, Ameur FZ, Roncero V, Fernandez-Bermejo M, Blanco G, Lopez D, Mateos JM, Salido GM, Gonzalez A. The melatonin receptor antagonist luzindole induces Ca 2+ mobilization, reactive oxygen species generation and impairs trypsin secretion in mouse pancreatic acinar cells. Biochim Biophys Acta Gen Subj 2019; 1863:129407. [PMID: 31381958 DOI: 10.1016/j.bbagen.2019.07.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 07/23/2019] [Accepted: 07/31/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND In this work we studied the effects of the melatonin receptor-antagonist luzindole (1 μM-50 μM) on isolated mouse pancreatic acinar cells. METHODS Changes in intracellular free-Ca2+ concentration, reactive oxygen species production and trypsin secretion were analyzed. RESULTS Luzindole induced increases in [Ca2+]i that diminished CCK-8 induced Ca2+ mobilization, compared with that observed when CCK-8 was applied alone. Treatment of cells with thapsigargin (1 μM), in the absence of Ca2+ in the extracellular medium, evoked a transient increase in [Ca2+]i. The additional incubation of cells with luzindole (10 μM) failed to induce further mobilization of Ca2+. In the presence of luzindole a concentration-dependent increase in ROS generation was observed that decreased in the absence of Ca2+ or by pretreatment of cells with melatonin (100 μM). Incubation of pancreatic acinar cells with luzindole (10 μM) impaired CCK-8-induced trypsin secretion. Melatonin was unable to revert the effect of luzindole on CCK-8-induced trypsin secretion. CONCLUSION The melatonin receptor-inhibitor luzindole induces Ca2+-mediated pro-oxidative conditions and impairment of enzyme secretion, which creates a situation in pancreatic acinar cells that might compromise their function. GENERAL SIGNIFICANCE The effects of luzindole that we have observed, might be unspecific and could mislead the observations when it is used to study the actions of melatonin on the gland. Another possibility is that melatonin receptors exhibit a basal or agonist-independent activity in pancreatic acinar cells, which might be modulated by melatonin or luzindole.
Collapse
Affiliation(s)
- Matias Estaras
- Institute of Molecular Pathology Biomarkers, University of Extremadura, Caceres, Spain
| | - Fatma Z Ameur
- Laboratoire de Physiologie de la Nutrition et de Sécurité Alimentaire, Université d'Oran1, Ahmed BenBella, Algeria
| | - Vicente Roncero
- Unit of Histology and Pathological Anatomy, Veterinary Faculty, University of Extremadura, Caceres, Spain
| | | | - Gerardo Blanco
- Hepatobiliary-Pancreatic Surgery and Liver Transplant Unit, Infanta Cristina Hospital, Badajoz, Spain
| | - Diego Lopez
- Hepatobiliary-Pancreatic Surgery and Liver Transplant Unit, Infanta Cristina Hospital, Badajoz, Spain
| | - Jose M Mateos
- Department of Gastroenterology, San Pedro de Alcantara Hospital, Caceres, Spain
| | - Gines M Salido
- Institute of Molecular Pathology Biomarkers, University of Extremadura, Caceres, Spain
| | - Antonio Gonzalez
- Institute of Molecular Pathology Biomarkers, University of Extremadura, Caceres, Spain.
| |
Collapse
|
6
|
Lee SB, Lee KW, Wang T, Lee JS, Jung US, Nejad JG, Oh YK, Baek YC, Kim KH, Lee HG. Intravenous administration of L-tryptophan stimulates gastrointestinal hormones and melatonin secretions: study on beef cattle. JOURNAL OF ANIMAL SCIENCE AND TECHNOLOGY 2019; 61:239-244. [PMID: 31452911 PMCID: PMC6686141 DOI: 10.5187/jast.2019.61.4.239] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 06/05/2019] [Accepted: 06/10/2019] [Indexed: 01/26/2023]
Abstract
This study aimed to determine the effective dose of intravenous administration of L-tryptophan (L-T) on gastrointestinal hormones (GIH) secretions and melatonin using Hanwoo cattle. Three steers (362 ± 23 kg) fitted with indwelling jugular vein catheters were assigned in a 3 × 3 Latin square design. Treatments were intravenous administration of saline (control), 28.9 mg L-T/kg body weight (BW; low) and 57.8 mg L-T/kg BW (high) L-T for 1 day with 7 days of adaptation. Samples were collected after adaptation period at -60, 0, 30, 60, 90, 120, 150, 180, 240, and 300 min of sampling day. The levels of serum cholecystokinin (CCK) and secretin were higher (p < 0.05) in the high L-T group than those in the other groups. Serum Melatonin (MEL) levels were increased upon L-T administration (p < 0.05) in the high L-T group. Taken together, the effective dose of L-T administration was defined at 57.8 mg L-T/kg BW in order to stimulate increase of GIH and MEL.
Collapse
Affiliation(s)
- Sang-Bum Lee
- Department of Animal Science and Technology, College of Animal
Bioscience and Technology, Konkuk University, Seoul 05029,
Korea
| | | | - Tao Wang
- Department of Animal Nutrition and Feed Science, College of Animal
Science and Technology, Jilin Agricultural University, Jilin 130118,
China
| | - Jae-Sung Lee
- Department of Animal Science and Technology, College of Animal
Bioscience and Technology, Konkuk University, Seoul 05029,
Korea
- An Educational Program for Specialists in Global Animal Science,
Brain Korea 21 Plus Project, Konkuk University, Seoul 05029,
Korea
| | - U-Suk Jung
- Department of Animal Science and Technology, College of Animal
Bioscience and Technology, Konkuk University, Seoul 05029,
Korea
| | - Jalil Ghassemi Nejad
- Department of Animal Science and Technology, College of Animal
Bioscience and Technology, Konkuk University, Seoul 05029,
Korea
- An Educational Program for Specialists in Global Animal Science,
Brain Korea 21 Plus Project, Konkuk University, Seoul 05029,
Korea
| | - Young-Kyoon Oh
- Department of Nutrition and Physiology, National Institute of
Animal Science, RDA, JeonJu 55365, Korea
| | - Youl-Chang Baek
- Department of Nutrition and Physiology, National Institute of
Animal Science, RDA, JeonJu 55365, Korea
| | - Kyoung Hoon Kim
- Graduate School of International Agricultural Technology,
Pyeongchang Campus, Seoul National University, Pyeongchang 25354,
Korea
| | - Hong-Gu Lee
- Department of Animal Science and Technology, College of Animal
Bioscience and Technology, Konkuk University, Seoul 05029,
Korea
- An Educational Program for Specialists in Global Animal Science,
Brain Korea 21 Plus Project, Konkuk University, Seoul 05029,
Korea
| |
Collapse
|
7
|
Estaras M, Moreno N, Santofimia-Castaño P, Martinez-Morcillo S, Roncero V, Blanco G, Lopez D, Fernandez-Bermejo M, Mateos JM, Iovanna JL, Salido GM, Gonzalez A. Melatonin induces reactive oxygen species generation and changes in glutathione levels and reduces viability in human pancreatic stellate cells. J Physiol Biochem 2019; 75:185-197. [PMID: 30868511 DOI: 10.1007/s13105-019-00671-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 02/26/2019] [Indexed: 12/12/2022]
Abstract
In this study, the effects of pharmacological concentrations of melatonin (1 μM-1 mM) on human pancreatic stellate cells (HPSCs) have been examined. Cell type-specific markers and expression of melatonin receptors were analyzed by western blot analysis. Changes in intracellular free Ca2+ concentration were followed by fluorimetric analysis of fura-2-loaded cells. Reduced glutathione (GSH) and oxidized glutathione (GSSG) levels were determined by fluorescence techniques. Production of reactive oxygen species (ROS) was monitored following 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate acetyl ester and MitoSOX™ Red-derived fluorescence. Cell viability was studied using the AlamarBlue® test. Cultured cells expressed markers typical of stellate cells. However, cell membrane receptors for melatonin could not be detected. Thapsigargin, bradykinin, or melatonin induced changes in intracellular free Ca2+ concentration. In the presence of the indole, a decrease in the GSH/GSSG ratio was observed that depended on the concentration of melatonin used. Furthermore, the indole evoked a concentration-dependent increase in ROS production in the mitochondria and in the cytosol. Finally, melatonin decreased HPSC viability in a time and concentration-dependent manner. We conclude that melatonin, at pharmacological concentrations, induces changes in the oxidative state of HPSC. This might regulate cellular viability and could not involve specific plasma membrane receptors.
Collapse
Affiliation(s)
- Matias Estaras
- Department of Physiology, Institute of Molecular Pathology Biomarkers, University of Extremadura, Avenida Universidad s/n, 10003, Cáceres, Spain
| | - Noelia Moreno
- Department of Physiology, Institute of Molecular Pathology Biomarkers, University of Extremadura, Avenida Universidad s/n, 10003, Cáceres, Spain
| | - Patricia Santofimia-Castaño
- Centre de Recherche en Cancérologie de Marseille, INSERM U1068, CNRS UMR 7258, Aix-Marseille Université and Institut Paoli-Calmettes, Parc Scientifique et Technologique de Luminy, Marseille, France
| | | | - Vicente Roncero
- Unit of Histology and Pathological Anatomy, Veterinary Faculty, University of Extremadura, Cáceres, Spain
| | - Gerardo Blanco
- Hepatobiliary-Pancreatic Surgery and Liver Transplant Unit, Infanta Cristina Hospital, Badajoz, Spain
| | - Diego Lopez
- Hepatobiliary-Pancreatic Surgery and Liver Transplant Unit, Infanta Cristina Hospital, Badajoz, Spain
| | | | - Jose M Mateos
- Department of Gastroenterology, San Pedro de Alcantara Hospital, Cáceres, Spain
| | - Juan L Iovanna
- Centre de Recherche en Cancérologie de Marseille, INSERM U1068, CNRS UMR 7258, Aix-Marseille Université and Institut Paoli-Calmettes, Parc Scientifique et Technologique de Luminy, Marseille, France
| | - Gines M Salido
- Department of Physiology, Institute of Molecular Pathology Biomarkers, University of Extremadura, Avenida Universidad s/n, 10003, Cáceres, Spain
| | - Antonio Gonzalez
- Department of Physiology, Institute of Molecular Pathology Biomarkers, University of Extremadura, Avenida Universidad s/n, 10003, Cáceres, Spain.
| |
Collapse
|
8
|
Tamtaji OR, Mirhosseini N, Reiter RJ, Behnamfar M, Asemi Z. Melatonin and pancreatic cancer: Current knowledge and future perspectives. J Cell Physiol 2018; 234:5372-5378. [PMID: 30229898 DOI: 10.1002/jcp.27372] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 08/17/2018] [Indexed: 12/13/2022]
Abstract
Pancreatic cancer has a high mortality rate due to the absence of early symptoms and subsequent late diagnosis; additionally, pancreatic cancer has a high resistance to radio- and chemotherapy. Multiple inflammatory pathways are involved in the pathophysiology of pancreatic cancer. Melatonin an indoleamine produced in the pineal gland mediated and receptor-independent action is the pancreas and other where has both receptors. Melatonin is a potent antioxidant and tissue protector against inflammation and oxidative stress. In vivo and in vitro studies have shown that melatonin supplementation is an appropriate therapeutic approach for pancreatic cancer. Melatonin may be an effective apoptosis inducer in cancer cells through regulation of a large number of molecular pathways including oxidative stress, heat shock proteins, and vascular endothelial growth factor. Limited clinical studies, however, have evaluated the role of melatonin in pancreatic cancer. This review summarizes what is known regarding the effects of melatonin on pancreatic cancer and the mechanisms involved.
Collapse
Affiliation(s)
- Omid Reza Tamtaji
- Physiology Research Center, Kashan University of Medical Sciences, Kashan, Iran
| | | | - Russel J Reiter
- Department of Cellular and Structural Biology, University of Texas Health Science, Center, San Antonio, Texas
| | - Morteza Behnamfar
- Student Research Committee, School of Medicine, North Khorasan University of Medical Sciences, Bojnurd, Iran
| | - Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran
| |
Collapse
|
9
|
Tachibana T, Kadomoto Y, Khan MSI, Makino R, Cline MA. Effect of l-tryptophan and its metabolites on food passage from the crop in chicks. Domest Anim Endocrinol 2018; 64:59-65. [PMID: 29753195 DOI: 10.1016/j.domaniend.2018.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/09/2018] [Accepted: 03/11/2018] [Indexed: 11/27/2022]
Abstract
l-tryptophan (l-Trp), an essential amino acid, is well known as a precursor of 5-hydroxytryptamine (5-HT) and melatonin. In mammals, l-Trp itself has been reported to suppress gastric emptying in mammals. In addition, 5-HT and melatonin are found in the gastrointestinal tract and affect food passage from the digestive tract in mammals. While the function of these factors in mammals is documented, there is little knowledge on their function in the digestive tract of birds. Therefore, the purpose of the present study was to determine if l-Trp and its metabolites affect the crop emptying rate in chicks (Gallus gallus). We also investigated the effects of kynurenic acid (KYNA) and quinolinic acid (QA), which are metabolites of the kynurenine pathway for l-Trp. Oral administration of l-Trp significantly reduced the crop emptying rate in chicks. Among the metabolites, intraperitoneal injection of 5-HT and melatonin significantly reduced the crop emptying rate, whereas KYNA and QA had no effect. The present study suggests that l-Trp, 5-HT, and melatonin inhibit the movement of food in the digestive tract and thereby affect the utilization of nutrients in the diet of chicks.
Collapse
Affiliation(s)
- T Tachibana
- Department of Agrobiological Science, Faculty of Agriculture, Ehime University, Matsuyama 790-8566, Japan.
| | - Y Kadomoto
- Department of Agrobiological Science, Faculty of Agriculture, Ehime University, Matsuyama 790-8566, Japan
| | - M S I Khan
- Department of Anatomy and Embryology, Ehime University Graduate School of Medicine, Toon 791-0295, Ehime, Japan
| | - R Makino
- Department of Agrobiological Science, Faculty of Agriculture, Ehime University, Matsuyama 790-8566, Japan
| | - M A Cline
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| |
Collapse
|
10
|
Jaworek J, Leja-Szpak A, Nawrot-Porąbka K, Szklarczyk J, Kot M, Pierzchalski P, Góralska M, Ceranowicz P, Warzecha Z, Dembinski A, Bonior J. Effects of Melatonin and Its Analogues on Pancreatic Inflammation, Enzyme Secretion, and Tumorigenesis. Int J Mol Sci 2017; 18:ijms18051014. [PMID: 28481310 PMCID: PMC5454927 DOI: 10.3390/ijms18051014] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 04/26/2017] [Accepted: 05/02/2017] [Indexed: 12/14/2022] Open
Abstract
Melatonin is an indoleamine produced from the amino acid l-tryptophan, whereas metabolites of melatonin are known as kynuramines. One of the best-known kynuramines is N1-acetyl-N1-formyl-5-methoxykynuramine (AFMK). Melatonin has attracted scientific attention as a potent antioxidant and protector of tissue against oxidative stress. l-Tryptophan and kynuramines share common beneficial features with melatonin. Melatonin was originally discovered as a pineal product, has been detected in the gastrointestinal tract, and its receptors have been identified in the pancreas. The role of melatonin in the pancreatic gland is not explained, however several arguments support the opinion that melatonin is probably implicated in the physiology and pathophysiology of the pancreas. (1) Melatonin stimulates pancreatic enzyme secretion through the activation of entero-pancreatic reflex and cholecystokinin (CCK) release. l-Tryptophan and AFMK are less effective than melatonin in the stimulation of pancreatic exocrine function; (2) Melatonin is a successful pancreatic protector, which prevents the pancreas from developing of acute pancreatitis and reduces pancreatic damage. This effect is related to its direct and indirect antioxidant action, to the strengthening of immune defense, and to the modulation of apoptosis. Like melatonin, its precursor and AFMK are able to mimic its protective effect, and it is commonly accepted that all these substances create an antioxidant cascade to intensify the pancreatic protection and acinar cells viability; (3) In pancreatic cancer cells, melatonin and AFMK activated a signal transduction pathway for apoptosis and stimulated heat shock proteins. The role of melatonin and AFMK in pancreatic tumorigenesis remains to be elucidated.
Collapse
Affiliation(s)
- Jolanta Jaworek
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University Medical College, 31-126 Kraków, Poland.
| | - Anna Leja-Szpak
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University Medical College, 31-126 Kraków, Poland.
| | - Katarzyna Nawrot-Porąbka
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University Medical College, 31-126 Kraków, Poland.
| | - Joanna Szklarczyk
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University Medical College, 31-126 Kraków, Poland.
| | - Michalina Kot
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University Medical College, 31-126 Kraków, Poland.
| | - Piotr Pierzchalski
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University Medical College, 31-126 Kraków, Poland.
| | - Marta Góralska
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University Medical College, 31-126 Kraków, Poland.
| | - Piotr Ceranowicz
- Department of Physiology, Faculty of Medicine, Jagiellonian University Medical College, 31-531 Kraków, Poland.
| | - Zygmunt Warzecha
- Department of Physiology, Faculty of Medicine, Jagiellonian University Medical College, 31-531 Kraków, Poland.
| | - Artur Dembinski
- Department of Physiology, Faculty of Medicine, Jagiellonian University Medical College, 31-531 Kraków, Poland.
| | - Joanna Bonior
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University Medical College, 31-126 Kraków, Poland.
| |
Collapse
|
11
|
Influence of nutrient restriction and melatonin supplementation of pregnant ewes on maternal and fetal pancreatic digestive enzymes and insulin-containing clusters. Animal 2016; 10:440-8. [DOI: 10.1017/s1751731115002219] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|
12
|
Nawrot-Porąbka K, Jaworek J, Leja-Szpak A, Kot M, Lange S. The role of antisecretory factor in pancreatic exocrine secretion: studies in vivo and in vitro. Exp Physiol 2015; 100:267-77. [PMID: 25641073 DOI: 10.1113/expphysiol.2014.083899] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 01/09/2015] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Antisecretory factor, an endogenous protein detected in many tissues of the body, is known as an inhibitor of intestinal secretion, but its role in pancreatic exocrine secretory function has not yet been investigated. What is the main finding and its importance? In a rodent model, we show that antisecretory factor reduces pancreatic exocrine secretion, probably via its direct action on the pancreatic acini and via modulation of the enteropancreatic reflexes involving cholecystokinin and sensory nerves. Antisecretory factor (AF) regulates ion and water transport through the intestinal cell membrane. Antisecretory factor inhibits intestinal secretion, but its effect on the exocrine pancreas has not yet been shown. We investigated the effect of AF on pancreatic amylase secretion in vivo and in vitro using pancreatic acini isolated by collagenase digestion. For the in vivo study, Wistar rats were surgically equipped with silicone catheters, inserted into the pancreaticobiliary duct and into the duodenum. Capsaicin was used to deactivate the sensory nerves in turn to assess their involvement in the effects of AF on the exocrine pancreas. Antisecretory factor (1, 3 or 10 μg kg(-1) i.p.) was given in basal conditions or following stimulation of pancreatic secretion with diversion of pancreaticobiliary juice. For the in vitro study, rat pancreatic acini were incubated in the presence of increasing doses of AF (from 10(-8) to 10(-5) m) alone or in combination with caerulein (10(-12) m). Cytoplasmic cholecystokinin 1 (CCK1 ) receptor protein was detected by Western blot and immunoprecipitation studies. Antisecretory factor markedly reduced the output of pancreatic amylase both in basal conditions and when stimulated by diversion of pancreaticobiliary juice. Deactivation of the sensory nerves with capsaicin completely reversed the inhibitory effects of AF on the exocrine pancreas. Caerulein-induced enzyme secretion from the pancreatic acini was inhibited by AF, whereas basal secretion was unaffected. Administration of AF to the rats significantly diminished the synthesis of CCK1 receptor protein. We conclude that AF inhibits pancreatic exocrine secretion indirectly via sensory nerves and directly decreases amylase release from isolated pancreatic acini. The direct inhibitory action of AF on the exocrine pancreas could be related, at least in part, to a reduction of CCK1 receptors on pancreatic acinar cells.
Collapse
Affiliation(s)
- Katarzyna Nawrot-Porąbka
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
| | | | | | | | | |
Collapse
|
13
|
Santofimia-Castaño P, Clea Ruy D, Garcia-Sanchez L, Jimenez-Blasco D, Fernandez-Bermejo M, Bolaños JP, Salido GM, Gonzalez A. Melatonin induces the expression of Nrf2-regulated antioxidant enzymes via PKC and Ca2+ influx activation in mouse pancreatic acinar cells. Free Radic Biol Med 2015; 87:226-36. [PMID: 26163001 DOI: 10.1016/j.freeradbiomed.2015.06.033] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Revised: 05/24/2015] [Accepted: 06/23/2015] [Indexed: 12/12/2022]
Abstract
The goal of this study was to evaluate the potential activation of the nuclear factor erythroid 2-related factor and the antioxidant-responsive element (Nrf2-ARE) signaling pathway in response to melatonin in isolated mouse pancreatic acinar cells. Changes in intracellular free Ca(2+) concentration were followed by fluorimetric analysis of fura-2-loaded cells. The activations of PKC and JNK were measured by Western blot analysis. Quantitative reverse transcription-polymerase chain reaction was employed to detect the expression of Nrf2-regulated antioxidant enzymes. Immunocytochemistry was employed to determine nuclear location of phosphorylated Nrf2, and the cellular redox state was monitored following MitoSOX Red-derived fluorescence. Our results show that stimulation of fura-2-loaded cells with melatonin (1 µM to 1 mM), in the presence of Ca(2+) in the extracellular medium, induced a slow and progressive increase of [Ca(2+)](c) toward a stable level. Melatonin did not inhibit the typical Ca(2+) response induced by CCK-8 (1 nM). When the cells were challenged with indoleamine in the absence of Ca(2+) in the extracellular solution (medium containing 0.5 mM EGTA) or in the presence of 1 mM LaCl(3), to inhibit Ca(2+) entry, we could not detect any change in [Ca(2+)](c). Nevertheless, CCK-8 (1 nM) was able to induce the typical mobilization of Ca(2+). When the cells were incubated with the PKC activator PMA (1 µM) in the presence of Ca(2+) in the extracellular medium, we observed a response similar to that noted when the cells were challenged with melatonin 100 µM. However, in the presence of Ro31-8220 (3 µM), a PKC inhibitor, stimulation of cells with melatonin failed to evoke changes in [Ca(2+)]c. Immunoblots, using an antibody specific for phospho-PKC, revealed that melatonin induces PKCα activation, either in the presence or in the absence of external Ca(2+). Melatonin induced the phosphorylation and nuclear translocation of the transcription factor Nrf2, and evoked a concentration-dependent increase in the expression of the antioxidant enzymes NAD(P)H-quinone oxidoreductase 1, catalytic subunit of glutamate-cysteine ligase, and heme oxygenase-1. Incubation of MitoSOX Red-loaded pancreatic acinar cells in the presence of 1 nM CCK-8 induced a statistically significant increase in dye-derived fluorescence, reflecting an increase in oxidation, that was abolished by pretreatment of cells with melatonin (100 µM) or PMA (1 µM). On the contrary, pretreatment with Ro31-8220 (3 µM) blocked the effect of melatonin on CCK-8-induced increase in oxidation. Finally, phosphorylation of JNK in the presence of CCK-8 or melatonin was also observed. We conclude that melatonin, via modulation of PKC and Ca(2+) signaling, could potentially stimulate the Nrf2-mediated antioxidant response in mouse pancreatic acinar cells.
Collapse
Affiliation(s)
| | - Deborah Clea Ruy
- Facultade de Agronomia & Medicina Veterinaria, Universidade de Brasilia, 70900-100, Brasilia DF, Brazil
| | - Lourdes Garcia-Sanchez
- Cell Physiology Research Group (FICEL), Department of Physiology, University of Extremadura, Caceres, Spain
| | - Daniel Jimenez-Blasco
- Institute of Functional Biology and Genomics (IBFG), University of Salamanca-CSIC, Salamanca, Spain
| | - Miguel Fernandez-Bermejo
- Cell Physiology Research Group (FICEL), Department of Physiology, University of Extremadura, Caceres, Spain; Department of Gastroenterology, San Pedro de Alcantara Hospital, E-10003 Caceres, Spain
| | - Juan P Bolaños
- Institute of Functional Biology and Genomics (IBFG), University of Salamanca-CSIC, Salamanca, Spain
| | - Gines M Salido
- Cell Physiology Research Group (FICEL), Department of Physiology, University of Extremadura, Caceres, Spain
| | - Antonio Gonzalez
- Cell Physiology Research Group (FICEL), Department of Physiology, University of Extremadura, Caceres, Spain.
| |
Collapse
|
14
|
Santofimia-Castaño P, Garcia-Sanchez L, Ruy DC, Sanchez-Correa B, Fernandez-Bermejo M, Tarazona R, Salido GM, Gonzalez A. Melatonin induces calcium mobilization and influences cell proliferation independently of MT1/MT2 receptor activation in rat pancreatic stellate cells. Cell Biol Toxicol 2015; 31:95-110. [DOI: 10.1007/s10565-015-9297-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 02/26/2015] [Indexed: 01/09/2023]
|
15
|
Identification of proteins involved in the pancreatic exocrine by exogenous ghrelin administration in Sprague-Dawley rats. JOURNAL OF ANIMAL SCIENCE AND TECHNOLOGY 2014; 56:6. [PMID: 26290695 PMCID: PMC4534188 DOI: 10.1186/2055-0391-56-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 05/07/2014] [Indexed: 11/30/2022]
Abstract
The aims of study were to investigate the effects of intraperitoneal (i.p.) infusion of ghrelin on pancreatic α-amylase outputs and the responses of pancreatic proteins to ghrelin that may relate to the pancreatic exocrine. Six male Sprague-Dawley rats (300 g) were randomly divided into two groups, a control group (C, n = 3) and a treatment group (T, 10.0μg/kg BW, n = 3). Blood samples were collected from rat caudal vein once time after one hour injection. The concentrations of plasma ghrelin, cholecystokinin (CCK) and alfa-amylase activity were evaluated by enzyme immunoassay (EIA) kit. Two-dimensional gel electrophoresis (2-DE) analysis was conducted to separate the proteins in pancreas tissue. Results showed that the i.p. infusion of ghrelin at doses of 10.0 μg/kg body weight (BW) increased the plasma ghrelin concentrations (p = 0.07) and elevated the plasma CCK level significantly (p < 0.05). Although there was no statistically significant, the α-amylase activity tended to increase. The proteomics analysis indicated that some pancreatic proteins with various functions were up- or down- regulated compared with control group. In conclusion, ghrelin may have role in the pancreatic exocrine, but the signaling pathway was still not clear. Therefore, much more functional studies focus on these found proteins are needed in the near future.
Collapse
|
16
|
Santofimia-Castaño P, Ruy DC, Salido GM, González A. Melatonin modulates Ca2+ mobilization and amylase release in response to cholecystokinin octapeptide in mouse pancreatic acinar cells. J Physiol Biochem 2013; 69:897-908. [PMID: 23904230 DOI: 10.1007/s13105-013-0267-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 06/12/2013] [Indexed: 01/01/2023]
Abstract
In the present work, we have evaluated the effect of an acute addition of melatonin on cholecystokinin octapeptide (CCK-8)-evoked Ca(2+) signals and amylase secretion in mouse pancreatic acinar cells. For this purpose, freshly isolated mouse pancreatic acinar cells were loaded with fura-2 to study intracellular free Ca(2+) concentration ([Ca(2+)](c)). Amylase release and cell viability were studied employing colorimetric methods. Our results show that CCK-8 evoked a biphasic effect on amylase secretion, finding a maximum at a concentration of 0.1 nM and a reduction of secretion at higher concentrations. Pre-incubation of cells with melatonin (1 μM-1 mM) significantly attenuated enzyme secretion in response to high concentrations of CCK-8. Stimulation of cells with 1 nM CCK-8 led to a transient increase in [Ca(2+)](c), followed by a decrease towards a constant level. In the presence of 1 mM melatonin, stimulation of cells with CCK-8 resulted in a smaller [Ca(2+)](c) peak response, a faster rate of decay of [Ca(2+)](c) and lower values for the steady state of [Ca(2+)](c), compared with the effect of CCK-8 alone. Melatonin also reduced the oscillatory pattern of Ca(2+) mobilization evoked by a physiological concentration of CCK-8 (20 pM), and completely inhibited Ca(2+) mobilization induced by 10 pM CCK-8. On the other hand, Ca(2+) entry from the extracellular space was not affected in the presence of melatonin. Finally, melatonin alone did not change cell viability. We conclude that melatonin, at concentrations higher than those found in blood, might regulate exocrine pancreatic function via modulation of Ca(2+) signals.
Collapse
Affiliation(s)
- Patricia Santofimia-Castaño
- Department of Physiology (Cell Physiology Research Group), University of Extremadura, Avenida Universidad s/n, 10003, Caceres, Spain
| | | | | | | |
Collapse
|
17
|
Nawrot-Porąbka K, Jaworek J, Leja-Szpak A, Szklarczyk J, Konturek SJ, Reiter RJ. Luminal melatonin stimulates pancreatic enzyme secretion via activation of serotonin-dependent nerves. Pharmacol Rep 2013; 65:494-504. [PMID: 23744434 DOI: 10.1016/s1734-1140(13)71025-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 11/26/2012] [Indexed: 01/07/2023]
Abstract
BACKGROUND Serotonin (5-HT) is released from enterochromaffin cells in the gastrointestinal tract. 5-HT, via the activation of 5-HT2 and 5-HT3 receptors on vagal fibers, mediates pancreatic secretion through the mechanism independent from cholecystokinin. Melatonin (5-HT derivative) or L-tryptophan (melatonin or 5-HT precursor) given systemically or intraduodenally to the rats stimulate amylase secretion, but the mechanism is not clear. The aim of this study was to investigate the involvement of 5-HT in the pancreatostimulatory effect of melatonin or L-tryptophan, administered intraduodenally. METHODS Wistar rats were surgically equipped with silicone catheters; inserted into pancreato-biliary duct and into the duodenum. Melatonin, L-tryptophan or 5-HT were given to the rats as a bolus. Combination of 5-HT2 or 5-HT3 receptor antagonists: ketanserin (100 μg/kg) and MDL72222 (250 μg/kg) was given intraperitoneally to the animals, 15 min. prior to the administration of the examined substances. The role of the vagal nerve, sensory fibers and CCK in the control of pancreatic exocrine function were determined. Blood samples were taken for the determination of 5-HT. RESULTS Melatonin, 5-HT or L-tryptophan increased pancreatic amylase secretion. The stimulatory effect of the above substances was decreased by pretreatment of the rats with ketanserin and MDL72222. Bilateral vagotomy completely abolished the increase of amylase output caused by 5-HT, while capsaicin deactivation of sensory nerves or blockade of CCK1 receptor only partially reversed the stimulatory effect of 5-HT on the pancreas. Intraduodenal L-tryptophan, but not melatonin, increased plasma 5-HT concentrations in a dose- and time-dependent manner. CONCLUSION Stimulation of pancreatic exocrine function caused by intraluminal administration of melatonin, or L-tryptophan is modified, at least in part, by serotoninergic mechanisms and vagal nerves.
Collapse
Affiliation(s)
- Katarzyna Nawrot-Porąbka
- Department of Medical Physiology, Faculty of Health Sciences, Jagiellonian University School of Medicine, Michałowskiego 12, PL 31-126 Kraków, Poland
| | | | | | | | | | | |
Collapse
|
18
|
Protective effect of melatonin on acute pancreatitis. Int J Inflam 2012; 2012:173675. [PMID: 22606640 PMCID: PMC3347751 DOI: 10.1155/2012/173675] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 01/22/2012] [Accepted: 02/02/2012] [Indexed: 02/04/2023] Open
Abstract
Melatonin, a product of the pineal gland, is released from the gut mucosa in response to food ingestion. Specific receptors for melatonin have been detected in many gastrointestinal tissues including the pancreas. Melatonin as well as its precursor, L-tryptophan, attenuates the severity of acute pancreatitis and protects the pancreatic tissue from the damage caused by acute inflammation. The beneficial effect of melatonin on acute pancreatitis, which has been reported in many experimental studies and supported by clinical observations, is related to: (1) enhancement of antioxidant defense of the pancreatic tissue, through direct scavenging of toxic radical oxygen (ROS) and nitrogen (RNS) species, (2) preservation of the activity of antioxidant enzymes; such as superoxide dismutase (SOD), catalase (CAT), or glutathione peroxidase (GPx), (3) the decline of pro-inflammatory cytokine tumor necrosis α (TNFα) production, accompanied by stimulation of an anti-inflammatory IL-10, (4) improvement of pancreatic blood flow and decrease of neutrophil infiltration, (5) reduction of apoptosis and necrosis in the inflamed pancreatic tissue, (6) increased production of chaperon protein (HSP60), and (7) promotion of regenerative process in the pancreas. Conclusion. Endogenous melatonin produced from L-tryptophan could be one of the native mechanisms protecting the pancreas from acute damage and accelerating regeneration of this gland. The beneficial effects of melatonin shown in experimental studies suggest that melatonin ought to be employed in the clinical trials as a supportive therapy in acute pancreatitis and could be used in people at high risk for acute pancreatitis to prevent the development of pancreatic inflammation.
Collapse
|
19
|
Oztürk G, Akbulut KG, Afrasyap L. Age-related changes in tissue and plasma zinc levels: modulation by exogenously administered melatonin. Exp Aging Res 2008; 34:453-62. [PMID: 18726755 DOI: 10.1080/03610730802271922] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Melatonin (MEL) is synthesized mainly in the pineal gland and derived from 5-hydroxytryptophan (5-HTP). Zinc (Zn) is one of the most important trace elements in the body. Zn and MEL levels are changed with aging. The aim of this study was to investigate the age-related changes of tissue and plasma Zn levels and effect of MEL administration on these parameters. Male wistar rats received for 3 weeks subcutaneous injection of MEL (10 mg/kg). Kidney and pancreas Zn levels in old rats were significantly lower than middle-aged group. Spleen, small intestine, and plasma Zn levels were not different in middle-aged and old rats. On the other hand, MEL treatment increased Zn levels of small intestine and plasma in middle-aged rats. However, kidney, spleen, and pancreas Zn levels were unaffected by MEL treatment.
Collapse
Affiliation(s)
- Güler Oztürk
- Department of Physiology, Faculty of Medicine, Maltepe University, Maltepe, Istanbul, Turkey.
| | | | | |
Collapse
|
20
|
Immunohistochemical definition of MT(2) receptors and melatonin in the gastrointestinal tissues of rat. Acta Histochem 2008; 112:26-33. [PMID: 19004484 DOI: 10.1016/j.acthis.2008.03.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Revised: 03/20/2008] [Accepted: 03/22/2008] [Indexed: 12/15/2022]
Abstract
The gastrointestinal tract of vertebrate species contains melatonin, which participates in several physiological functions. Some of these effects are mediated via specific membrane receptors (MT(1) and MT(2)). In the present study, the distribution of the MT(2) receptor protein in the gastrointestinal tract was localized, and changes in MT(2) receptor density were observed in relation to the expected circadian changes in melatonin concentrations. Immunohistochemistry was performed in the rat stomach, duodenum, colon and pancreas. The amount of MT(2) was determined by Western blot. Melatonin concentrations were measured by radioimmunoassay (RIA). In the stomach, duodenum and colon, the most intense immunoreactivity was observed in the Muscularis mucosae and in the Muscularis externa. In the pancreas, the immunolabelling was less intense. There was a clear daily rhythm of melatonin concentrations in the stomach, duodenum and pancreas, with higher levels during the dark period. The density of MT(2) receptors did not exhibit circadian variation. Moreover, circadian changes in melatonin concentrations were not found in the colon. The density of MT(2) was the highest in the colon. Our results provide evidence for the heterogeneous distribution of MT(2) receptors in different parts and layers of the gastrointestinal tract, which could indicate a physiological role of melatonin in the gastrointestinal tract.
Collapse
|
21
|
Aras HC, Ekström J. Melatonin-evoked in vivo secretion of protein and amylase from the parotid gland of the anaesthetised rat. J Pineal Res 2008; 45:413-21. [PMID: 18637985 DOI: 10.1111/j.1600-079x.2008.00609.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The intravenous infusion of melatonin (5 and 25 mg/kg over 10 min) evoked a dose-dependent output of protein and amylase but no overt fluid secretion from the parotid gland of the pentobarbitone-anaesthetised rat, as revealed by increased concentrations of protein and amylase activity in a subsequent wash-out flow of saliva in response to an intravenous bolus injection of methacholine (5 microg/kg) 10 min later. The secretory responses to melatonin occurred in the presence of alpha- and beta-adrenoceptor antagonists. They were not affected by the cholecystokinin A-receptor antagonist, lorglumide, and they were reproduced in eviscerated animals acutely subjected to postganglionic sympathetic and parasympathetic denervation of the gland. The responses to melatonin were partially dependent on nitric oxide generation, through the activity of nitric oxide synthase of the neuronal type. Immunoblotting showed both melatonin receptors of type 1 and type 2 to be expressed in parotid gland tissue. The relative specific melatonin 2-receptor antagonist luzindole prevented the expected secretory effects of melatonin. The results favour a direct action by melatonin on melatonin receptors of parotid secretory cells and suggest a potential physiological role for melatonin in the regulation of salivary glandular activities.
Collapse
Affiliation(s)
- Hülya Cevik Aras
- Section of Pharmacology, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at Göteborg University, Göteborg, Sweden
| | | |
Collapse
|
22
|
Koppisetti S, Jenigiri B, Terron MP, Tengattini S, Tamura H, Flores LJ, Tan DX, Reiter RJ. Reactive oxygen species and the hypomotility of the gall bladder as targets for the treatment of gallstones with melatonin: a review. Dig Dis Sci 2008; 53:2592-603. [PMID: 18338264 DOI: 10.1007/s10620-007-0195-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Accepted: 12/21/2007] [Indexed: 12/17/2022]
Abstract
Free radical-mediated damage of the gall bladder epithelium predisposes to the development of both gall bladder inflammation and gallstone formation, which often coexist. Melatonin, a pineal and gut secretory product, due to its antioxidant activity along with its effect on the aging gall bladder myocytes, inhibits gallstone formation. Melatonin reduces the biliary levels of cholesterol by inhibiting cholesterol absorption across the intestinal epithelium and by increasing the conversion of cholesterol to bile acids. The incidence of gallstones is increasing and is expected to rise dramatically with the increase in the longevity and the risk factors such as obesity. The change in the prevalence of cholelithiasis is associated with a proportionate rise in the incidence of cholangiocarcinoma. In an attempt to improve the quality of life of the rapidly increasing aging population, this article reviews up-to-date information on the pathophysiology of the gall bladder function and discusses the development of new therapies with potential good patient compliance and lower cost than the current treatments.
Collapse
Affiliation(s)
- Sreedevi Koppisetti
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Nisbet DJ, Edrington TS, McReynolds JL, Callaway TR, Byrd JA. Influence of exogenous melatonin administration on Salmonella enteritidis colonization in molted layers. Poult Sci 2008; 87:1083-8. [PMID: 18492995 DOI: 10.3382/ps.2008-00016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two studies were conducted to evaluate the effects of melatonin on Salmonella Enteritidis infection in experimentally challenged laying hens subjected to a forced molt. Leghorn hens (>50 wk of age) were randomly assigned to rooms, acclimated to a 16L:8D regimen, and provided ad libitum access to a nonmedicated mash layer diet and water. Birds in one room were molted (8L:16D; complete feed withdrawal), whereas birds in the second room served as nonmolted controls (CONT). Within each room, birds were randomly assigned to melatonin treatment (MEL; 12 birds/treatment), dosed orally commencing the same day as feed withdrawal for 10 d: (experiment I: 0 or 5 mg of melatonin; experiment II: 0, 10, or 20 mg of melatonin). Three days following feed withdrawal, all birds were experimentally infected with Salmonella Enteritidis, and after 10 d of feed withdrawal, all birds were killed and necropsied. In experiment I, concentrations of Salmonella Enteritidis in the cecal contents and the number of Salmonella Enteritidis-positive tissues from the crop, ceca, liver, spleen, and ovary were higher (P < 0.0001) in the MOLT compared with the CONT treatments. No differences (P > 0.10) were observed in any of the parameters examined due to MEL treatment. For experiment II, cecal concentrations of Salmonella Enteritidis were generally higher in the MOLT compared with the CONT treatment and within molted birds, cecal concentrations were higher in the MEL treatment (P < 0.05). Melatonin treatment in molted birds increased (P < 0.05) the percentage of positive crops in the MOLT+20 MEL treatment (P < 0.05). Salmonella-positive cecal tissue was increased (P < 0.001) in MOLT compared with CONT birds and was also higher in MOLT+10 MEL and MOLT+20 MEL birds compared with the MOLT-only treatment. Results from the current research suggest that dosage with high levels of melatonin may exacerbate Salmonella Enteritidis infection in layers subjected to forced molt.
Collapse
Affiliation(s)
- D J Nisbet
- Food and Feed Safety Research Unit, Southern Plains Agricultural Research Center, USDA-ARS, College Station, TX 77845, USA.
| | | | | | | | | |
Collapse
|
24
|
Guzzetti S, Calcagno E, Canetta A, Sacchetti G, Fracasso C, Caccia S, Cervo L, Invernizzi RW. Strain differences in paroxetine-induced reduction of immobility time in the forced swimming test in mice: role of serotonin. Eur J Pharmacol 2008; 594:117-24. [PMID: 18691569 DOI: 10.1016/j.ejphar.2008.07.031] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Revised: 07/11/2008] [Accepted: 07/21/2008] [Indexed: 11/16/2022]
Abstract
We studied the antidepressant-like effect of paroxetine in strains of mice carrying different isoforms of tryptophan hydroxylase-2 (TPH-2), the enzyme responsible for the synthesis of brain serotonin (5-HT). The effect of paroxetine alone and in combination with pharmacological treatments enhancing or lowering 5-HT synthesis or melatonin was assessed in the forced swimming test in mice carrying allelic variants of TPH-2 (1473C in C57BL/6 and 1473G in DBA/2 and BALB/c). Changes in brain 5-hydroxytryptophan (5-HTP) accumulation and melatonin levels were measured by high-performance liquid chromatography. Paroxetine (2.5 and 5 mg/kg) reduced immobility time in C57BL/6J and C57BL/6N mice but had no such effect in DBA/2J, DBA/2N and BALB/c mice, even at 10 mg/kg. Enhancing 5-HT synthesis with tryptophan reinstated the antidepressant-like effect of paroxetine in DBA/2J, DBA/2N and BALB/c mice whereas inhibition of 5-HT synthesis prevented the effect of paroxetine in C57BL/6N mice. The response to paroxetine was not associated with changes in locomotor activity, brain melatonin or brain levels of the drug measured at the end of the behavioral test. These results support the importance of 5-HT synthesis in the response to SSRIs and suggest that melatonin does not contribute to the ability of tryptophan to rescue the antidepressant-like effect of paroxetine.
Collapse
Affiliation(s)
- Sara Guzzetti
- Istituto di Ricerche Farmacologiche Mario Negri, Department of Neuroscience, Laboratory of Experimental Psychopharmacology, Via La Masa 19, 20156 Milan, Italy
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Edrington TS, Callaway TR, Hallford DM, Chen L, Anderson RC, Nisbet DJ. Effects of exogenous melatonin and tryptophan on fecal shedding of E. coli O157:H7 in cattle. MICROBIAL ECOLOGY 2008; 55:553-60. [PMID: 17874261 DOI: 10.1007/s00248-007-9300-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Revised: 06/12/2007] [Accepted: 06/29/2007] [Indexed: 05/17/2023]
Abstract
Fecal prevalence of Escherichia coli O157 in ruminants is highest in the summer decreasing to very low levels in the winter. We hypothesize that this seasonal variation is a result of physiological responses within the host animal to changing day-length. To determine the effects of melatonin (MEL) on fecal shedding of E. coli O157:H7 in cattle, eight crossbred beef steers identified as shedding E. coli O157:H7, were allotted to treatment: control or MEL (0.5 mg/kg body weight (BW); 1x) administered orally daily for 7 days. After a 5-day period of no treatment, a second MEL dose (5.0 mg/kg BW; 10x) was administered daily for 4 days. Fecal samples were collected daily for qualification of E. coli O157:H7. No differences (P > 0.10) were observed in the percentage of E. coli O157:H7 positive fecal samples in steers receiving the 1x MEL dose, however the 10x dose decreased (P = 0.05) the percentage of fecal samples E. coli O157:H7 positive. Serum MEL concentrations were higher in the 1x, but not 10x, treated animals compared to control animals. Although it is difficult to explain, this may be a result of decreasing day-length increasing serum melatonin concentrations that may have masked any treatment effect on serum melatonin. In a second similar experiment, a second group of cattle (heifers and steers) were administered tryptophan (TRP) over a 17-day experimental period (5 g/head/day for 10 days followed by 10 g/head/day for 7 days). Tryptophan had no effect (P > 0.20) on the percentage of fecal samples positive for E. coli O157. Serum TRP (P < 0.05), but not MEL (P > 0.20), concentrations were elevated in TRP-treated animals. The decrease in the number of positive fecal samples observed in the first experiment, may be related to gastrointestinal MEL, affected by the 10x, but not 1x MEL dose.
Collapse
Affiliation(s)
- Tom S Edrington
- Food and Feed Safety Research Unit, Southern Plains Agricultural Research Center, USDA-ARS, College Station, TX 77845, USA.
| | | | | | | | | | | |
Collapse
|
26
|
Klupińska G, Poplawski T, Drzewoski J, Harasiuk A, Reiter RJ, Blasiak J, Chojnacki J. Therapeutic effect of melatonin in patients with functional dyspepsia. J Clin Gastroenterol 2007; 41:270-4. [PMID: 17426465 DOI: 10.1097/mcg.0b013e318031457a] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND GOAL Melatonin may inhibit reactive oxygen species-related pathogenesis in the alimentary tract by neutralizing free radicals. In the present study we assessed the potential protective action of melatonin in ulcerlike dyspepsia. STUDY Sixty patients aged 19 to 39 years with the diagnosis of functional dyspepsia according to the Rome Criteria II and no Helicobacter pylori infection were involved in the study. Melatonin, at a dose of 5 mg (n=30), or placebo (n=30) were taken in the evening for a period of 12 weeks. At this time, patients were on an equivalent diet and were only to take an alkaline drug in case of the abdominal pain. RESULTS After 12 weeks, the dyspeptic symptoms completely subsided in 17 patients in the melatonin-treatment group (56.6%). In other 9 individuals (30.0%) a partial improvement in health was achieved, especially in the frequency and intensity of nocturnal pain. After placebo, the majority of patients (93.3%) did not experience any improvement in symptoms. Multivariate analysis indicated that melatonin (odds ratio 95.86, 95% confidence interval 3.72-2469.37, P<0.01) correlated independently with significantly improved patients health. H. pylori past infection decreased positive effect of melatonin in ulcerlike dyspepsia. CONCLUSIONS Melatonin can be considered as an auxiliary drug in the treatment of ulcerlike dyspepsia.
Collapse
Affiliation(s)
- Grazyna Klupińska
- Department of Gastroenterology and Internal Medicine, Medical University of Lodz, Lodz, Poland
| | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
Melatonin was thought to originate primarily from the pineal gland and to be secreted during the night, but recent studies revealed that gastrointestinal (GI) tract presents another, many times larger, source of melatonin that contributes significantly to the circulating concentration of this indole. Melatonin may exert a direct effect on GI tissues but its major influence on GI organs seems to occur indirectly, via the brain-gut axis including peripheral receptors, sensory afferent (vagal or sympathetic) pathways and central nervous system (CNS) acting on these organs via autonomic efferents and neuromediators. This article reviews and updates our experience with the fascinating molecule, as related to GI organs, with special focus on secretory activity of the stomach and pancreas and the maintenance of their tissue integrity. In addition to being released into the circulation, melatonin is also discharged into the gut lumen and this appears to be implicated in the postprandial stimulation of pancreatic enzyme secretion, mediated by melatonin-induced release of cholecystokinin, acting through entero-gastro-pancreatic reflexes. Although exerting certain differences in the mechanism of action on gastric and pancreatic secretory activities, melatonin derived from its precursor L-tryptophan, exhibits similar highly protective actions against the damage of both the stomach and the pancreas and accelerates the healing of chronic gastric ulcerations by stimulating the microcirculation and cooperating with arachidonate metabolites such as prostaglandins, with nitric oxide released from vascular endothelium, and/or sensory nerves and with their neuropeptides such as calcitonin gene related peptide. The beneficial effects of melatonin results in gastro- and pancreato-protection, prevents various forms of gastritis and pancreatitis through the activation of specific MT2-receptors and scavenges reactive oxygen species (ROS). Melatonin counteracts the increase in the ROS-induced lipid peroxidation and preserves, at least in part, the activity of key anti-oxidizing enzymes such as superoxide dismutase. It is proposed that melatonin should be considered as the agent exerting an important role in prevention of gastric and pancreatic damage and in accelerating healing of gastric ulcers.
Collapse
Affiliation(s)
- Jolanta Jaworek
- Department of Physiology, Jagiellonian University College of Medicine, Cracow, Poland
| | | | | |
Collapse
|