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Trevizol JS, Dionizio A, Delgado AQ, Ventura TMO, Ribeiro CFDS, Ribeiro L, Buzalaf NR, Cestari TM, Magalhães AC, Suzuki M, Bosqueiro JR, Buzalaf MAR. Metabolic effect of low fluoride levels in the islets of NOD mice: integrative morphological, immunohistochemical, and proteomic analyses. J Appl Oral Sci 2023; 31:e20230036. [PMID: 37283331 PMCID: PMC10247282 DOI: 10.1590/1678-7757-2023-0036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/31/2023] [Accepted: 05/03/2023] [Indexed: 06/08/2023] Open
Abstract
OBJECTIVES Fluoride (F) has been widely used to control dental caries, and studies suggest beneficial effects against diabetes when a low dose of F is added to the drinking water (10 mgF/L). This study evaluated metabolic changes in pancreatic islets of NOD mice exposed to low doses of F and the main pathways altered by the treatment. METHODOLOGY In total, 42 female NOD mice were randomly divided into two groups, considering the concentration of F administered in the drinking water for 14 weeks: 0 or 10 mgF/L. After the experimental period, the pancreas was collected for morphological and immunohistochemical analysis, and the islets for proteomic analysis. RESULTS In the morphological and immunohistochemical analysis, no significant differences were found in the percentage of cells labelled for insulin, glucagon, and acetylated histone H3, although the treated group had higher percentages than the control group. Moreover, no significant differences were found for the mean percentages of pancreatic areas occupied by islets and for the pancreatic inflammatory infiltrate between the control and treated groups. Proteomic analysis showed large increases in histones H3 and, to a lesser extent, in histone acetyltransferases, concomitant with a decrease in enzymes involved in the formation of acetyl-CoA, besides many changes in proteins involved in several metabolic pathways, especially energy metabolism. The conjunction analysis of these data showed an attempt by the organism to maintain protein synthesis in the islets, even with the dramatic changes in energy metabolism. CONCLUSION Our data suggests epigenetic alterations in the islets of NOD mice exposed to F levels comparable to those found in public supply water consumed by humans.
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Affiliation(s)
- Juliana Sanches Trevizol
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Ciências Biológicas, Bauru, SP, Brasil
| | - Aline Dionizio
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Ciências Biológicas, Bauru, SP, Brasil
| | | | | | | | - Laura Ribeiro
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Ciências Biológicas, Bauru, SP, Brasil
| | - Nathalia Rabelo Buzalaf
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Ciências Biológicas, Bauru, SP, Brasil
| | - Tânia Mary Cestari
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Ciências Biológicas, Bauru, SP, Brasil
| | - Ana Carolina Magalhães
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Ciências Biológicas, Bauru, SP, Brasil
| | - Maiko Suzuki
- The Dental College of Georgia, Department of Oral Biology and Diagnostic Sciences, Augusta, Georgia, United States
| | - José Roberto Bosqueiro
- Universidade Estadual Paulista, Faculdade de Ciências, Departamento de Educação Física, Bauru, São Paulo, Brasil
| | - Marília Afonso Rabelo Buzalaf
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Ciências Biológicas, Bauru, SP, Brasil
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Zimath PL, Almeida MS, Bruxel MA, Rafacho A. Oral mometasone furoate administration preserves anti-inflammatory action with fewer metabolic adverse effects in rats. Biochem Pharmacol 2023; 210:115486. [PMID: 36893817 DOI: 10.1016/j.bcp.2023.115486] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 03/09/2023]
Abstract
BACKGROUND Exogenous glucocorticoids (CGs) possess relevant therapeutic effects but exert diabetogenic actions when in excess. Thus, ligands with potential therapeutic applications and fewer adverse effects are needed. To this, we analyzed whether mometasone furoate (MF), a CG expected to cause fewer side effects, given through systemic routes, could maintain the anti-inflammatory actions without relevant repercussions on metabolism. METHODS The anti-inflammatory effect of MF was evaluated with both peritonitis and colitis models in rodents. Glucose and lipid metabolism were investigated in male and female rats treated daily with MF with different doses and routes of administration for seven days. The involvement of glucocorticoid receptor (GR) on MF actions was assessed in animals pretreated with mifepristone. Also, the potential reversibility of the adverse effects was assessed. Dexamethasone was used as a positive control. RESULTS MF treatment resulted in glucose intolerance in male rats treated through intraperitoneal (ip) but not oral gavage route (og). In female rats, none of the routes led to glucose intolerance. MF treatment attenuated insulin sensitivity and increased pancreatic β-cell mass, regardless of the sex and route of administration. MF treatment through og route did not result in dyslipidemia, as observed in rats treated through the ip route (both sexes). The anti-inflammatory and metabolic adverse effects of MF were GR-dependent, and metabolic outcomes altered by MF administration were reversible. CONCLUSION MF maintains anti-inflammatory activity when administered by systemic routes and exerts less impact on metabolism when administered orally in male and female rats, effects that are GR-dependent and reversible. Category: Metabolic Disorders and Endocrinology.
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Affiliation(s)
- Priscila L Zimath
- Laboratory of Investigation in Chronic Diseases - LIDoC, Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina - UFSC, Florianópolis, Brazil; Graduate Program in Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina - UFSC, Florianópolis, Brazil
| | - Milena S Almeida
- Laboratory of Investigation in Chronic Diseases - LIDoC, Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina - UFSC, Florianópolis, Brazil
| | - Maciel A Bruxel
- Laboratory of Investigation in Chronic Diseases - LIDoC, Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina - UFSC, Florianópolis, Brazil; Multicenter Graduate Program in Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina - UFSC, Florianópolis, Brazil
| | - Alex Rafacho
- Laboratory of Investigation in Chronic Diseases - LIDoC, Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina - UFSC, Florianópolis, Brazil; Graduate Program in Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina - UFSC, Florianópolis, Brazil; Multicenter Graduate Program in Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina - UFSC, Florianópolis, Brazil.
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Cheon SY, Song J. Novel insights into non-alcoholic fatty liver disease and dementia: insulin resistance, hyperammonemia, gut dysbiosis, vascular impairment, and inflammation. Cell Biosci 2022; 12:99. [PMID: 35765060 PMCID: PMC9237975 DOI: 10.1186/s13578-022-00836-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 06/20/2022] [Indexed: 02/08/2023] Open
Abstract
AbstractNon-alcoholic fatty liver disease (NAFLD) is a metabolic disease characterized by multiple pathologies. The progression of dementia with NAFLD may be affected by various risk factors, including brain insulin resistance, cerebrovascular dysfunction, gut dysbiosis, and neuroinflammation. Many recent studies have focused on the increasing prevalence of dementia in patients with NAFLD. Dementia is characterized by cognitive and memory deficits and has diverse subtypes, including vascular dementia, Alzheimer’s dementia, and diabetes mellitus-induced dementia. Considering the common pathological features of NAFLD and dementia, further studies on the association between them are needed to find appropriate therapeutic solutions for diseases. This review summarizes the common pathological characteristics and mechanisms of NAFLD and dementia. Additionally, it describes recent evidence on association between NAFLD and dementia progression and provides novel perspectives with regard to the treatment of patients with dementia secondary to NAFLD.
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Mousa SA, Dehe L, Aboryag N, Shaqura M, Beyer A, Schäfer M, Treskatsch S. Identification of glucocorticoid receptors as potential modulators of parasympathetic and sympathetic neurons within rat intracardiac ganglia. Front Neuroanat 2022; 16:902738. [PMID: 36213610 PMCID: PMC9539283 DOI: 10.3389/fnana.2022.902738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 09/07/2022] [Indexed: 11/30/2022] Open
Abstract
Background Emerging evidences indicate that glucocorticoid receptors (GR) play a regulatory role in cardiac function, particularly with regard to the autonomic nervous system. Therefore, this study aimed to demonstrate the expression and the precise anatomical location of GR in relation to the parasympathetic and sympathetic innervations of the heart. Methods The present study used tissue samples from rat heart atria to perform conventional reverse-transcriptase polymerase chain reaction (RT-PCR), Western blot, and double immunofluorescence confocal analysis of GR with the neuronal markers vesicular acetylcholine transporter (VAChT), tyrosine hydroxylase (TH), calcitonin gene-related peptide (CGRP) as well as the mineralocorticoid receptor (MR). Results Double immunofluorescence labeling revealed that GRs were co-expressed with VAChT in parasympathetic principal neuronal somata and nerve terminals innervating atrium. Also, GR colocalized with the sympathetic neuronal marker TH in a cluster of small intensely fluorescent (SIF) cells, on intracardiac nerve terminals and in the atrial myocardium. GR immunoreactivity was scarcely identified on CGRP-immunoreactive sensory nerve terminals. Approximately 20% of GR immunoreactive neuronal somata co-localized with MR. Finally, conventional RT-PCR and Western blot confirmed the presence of GR and MR in rat heart atria. Conclusion This study provides evidence for the existence of GR predominantly on cardiac parasympathetic neurons and TH-immunoreactive SIF cells suggesting a functional role of cardiac GR on cardiovascular function by modulation of the cardiac autonomic nervous system.
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Affiliation(s)
- Shaaban A. Mousa
- Department of Anaesthesiology and Intensive Care Medicine, Charité – University Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Lukas Dehe
- Department of Anaesthesiology and Intensive Care Medicine, Charité – University Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Noureddin Aboryag
- Department of Anaesthesiology and Intensive Care Medicine, Charité – University Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Mohammed Shaqura
- Department of Anaesthesiology and Intensive Care Medicine, Charité – University Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Antje Beyer
- Department of Anaesthesiology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Michael Schäfer
- Department of Anaesthesiology and Intensive Care Medicine, Charité – University Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Sascha Treskatsch
- Department of Anaesthesiology and Intensive Care Medicine, Charité – University Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
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Natividade da Silva F, Brunetta HS, Bruxel MA, Gomes FA, Rafacho A. Impact of glucocorticoid treatment before pregnancy on glucose homeostasis of offspring exposed to glucocorticoid in adult life. Life Sci 2019; 237:116913. [DOI: 10.1016/j.lfs.2019.116913] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 09/24/2019] [Accepted: 09/24/2019] [Indexed: 12/31/2022]
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Gomes FA, Flores RA, Bruxel MA, da Silva FN, Moreira ELG, Zoccal DB, Prediger RD, Rafacho A. Glucose Homeostasis Is Not Affected in a Murine Model of Parkinson's Disease Induced by 6-OHDA. Front Neurosci 2019; 12:1020. [PMID: 30686986 PMCID: PMC6333712 DOI: 10.3389/fnins.2018.01020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 12/18/2018] [Indexed: 01/09/2023] Open
Abstract
There is a mutual relationship between metabolic and neurodegenerative diseases. However, the causal relationship in this crosstalk is unclear and whether Parkinson’s disease (PD) causes a posterior impact on metabolism remains unknown. Considering that, this study aimed to evaluate the appearance of possible changes in metabolic homeostasis due to 6-hydroxydopamine (6-OHDA) administration, a neurotoxin that damage dopaminergic neurons leading to motor impairments that resemble the ones observed in PD. For this, male Wistar rats received bilateral 6-OHDA administration in the dorsolateral striatum, and the motor and metabolic outcomes were assessed at 7, 21, or 35 days post-surgical procedure. Dexamethasone, a diabetogenic glucocorticoid (GC), was intraperitoneally administered in the last 6 days to challenge the metabolism and reveal possible metabolic vulnerabilities caused by 6-OHDA. Controls received only vehicles. The 6-OHDA-treated rats displayed a significant decrease in locomotor activity, exploratory behavior, and motor coordination 7 and 35 days after neurotoxin administration. These motor impairments paralleled with no significant alteration in body mass, food intake, glucose tolerance, insulin sensitivity, and biochemical parameters (plasma insulin, triacylglycerol, and total cholesterol levels) until the end of the experimental protocol on days 35–38 post-6-OHDA administration. Moreover, hepatic glycogen and fat content, as well as the endocrine pancreas mass, were not altered in rats treated with 6-OHDA at the day of euthanasia (38th day after neurotoxin administration). None of the diabetogenic effects caused by dexamethasone were exacerbated in rats previously treated with 6-OHDA. Thus, we conclude that bilateral 6-OHDA administration in the striatum causes motor deficits in rats with no impact on glucose and lipid homeostasis and does not exacerbate the adverse effects caused by excess GC. These observations indicate that neurodegeneration of dopaminergic circuits in the 6-OHDA rats does not affect the metabolic outcomes.
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Affiliation(s)
- Felipe Azevedo Gomes
- Postgraduate Program in Pharmacology, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Rafael Appel Flores
- Multicenter Postgraduate Program in Physiological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Maciel Alencar Bruxel
- Multicenter Postgraduate Program in Physiological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Flávia Natividade da Silva
- Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Eduardo Luiz Gasnhar Moreira
- Multicenter Postgraduate Program in Physiological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil.,Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Daniel Breseghello Zoccal
- Department of Physiology and Pathology, School of Dentistry, São Paulo State University, Araraquara, Brazil
| | - Rui Daniel Prediger
- Postgraduate Program in Pharmacology, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Alex Rafacho
- Postgraduate Program in Pharmacology, Federal University of Santa Catarina, Florianópolis, Brazil.,Multicenter Postgraduate Program in Physiological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil.,Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil
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Inácio MD, Rafacho A, de Paula Camaforte NA, Teixeira P, Vareda PMP, Violato NM, Bosqueiro JR. Prevention of Elevation in Plasma Triacylglycerol with High-Dose Bezafibrate Treatment Abolishes Insulin Resistance and Attenuates Glucose Intolerance Induced by Short-Term Treatment with Dexamethasone in Rats. Int J Endocrinol 2018; 2018:3257812. [PMID: 30532777 PMCID: PMC6250034 DOI: 10.1155/2018/3257812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 08/07/2018] [Accepted: 08/27/2018] [Indexed: 12/04/2022] Open
Abstract
OBJECTIVE Fibrates are used as lipid-lowering drugs and are well tolerated as cotreatments when glucose metabolism disturbances are also present. Synthetic glucocorticoids (GCs) are diabetogenic drugs that cause dyslipidemia, dysglycemia, glucose intolerance, and insulin resistance when in excess. Thus, we aimed to describe the potential of bezafibrate in preventing or attenuating the adverse effects of GCs on glucose and lipid homeostasis. METHODS Male Wistar rats were treated with high-dose bezafibrate (300 mg/kg, body mass (b.m.)) daily for 28 consecutive days. In the last five days, the rats were also treated with dexamethasone (1 mg/kg, b.m.). RESULTS Dexamethasone treatment reduced the body mass gain and food intake, and bezafibrate treatment exerted no impact on these parameters. GC treatment caused an augmentation in fasting and fed glycemia, plasma triacylglycerol and nonesterified fatty acids, and insulinemia, and bezafibrate treatment completely prevented the elevation in plasma triacylglycerol and attenuated all other parameters. Insulin resistance and glucose intolerance induced by GC treatment were abolished and attenuated, respectively, by bezafibrate treatment. CONCLUSION High-dose bezafibrate treatment prevents the increase in plasma triacylglycerol and the development of insulin resistance and attenuates glucose intolerance in rats caused by GC treatment, indicating the involvement of dyslipidemia in the GC-induced insulin resistance.
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Affiliation(s)
- Maiara Destro Inácio
- Institute of Biosciences, São Paulo State University–UNESP, Botucatu, SP, Brazil
| | - Alex Rafacho
- Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina–UFSC, Florianópolis, SC, Brazil
| | | | - Poliana Teixeira
- Institute of Biosciences, São Paulo State University–UNESP, Botucatu, SP, Brazil
| | | | | | - José Roberto Bosqueiro
- Department of Physical Education, Faculty of Sciences, São Paulo State University–UNESP, Bauru, SP, Brazil
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Chronic low-dose glucocorticoid treatment increases subcutaneous abdominal fat, but not visceral fat, of male Wistar rats. Life Sci 2017; 190:29-35. [DOI: 10.1016/j.lfs.2017.09.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 09/13/2017] [Accepted: 09/24/2017] [Indexed: 11/19/2022]
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Impact of Fish Oil Supplementation and Interruption of Fructose Ingestion on Glucose and Lipid Homeostasis of Rats Drinking Different Concentrations of Fructose. BIOMED RESEARCH INTERNATIONAL 2017; 2017:4378328. [PMID: 28929113 PMCID: PMC5591931 DOI: 10.1155/2017/4378328] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 06/20/2017] [Accepted: 06/28/2017] [Indexed: 12/28/2022]
Abstract
Background. Continuous fructose consumption may cause elevation of circulating triacylglycerol. However, how much of this alteration is reverted after the removal of fructose intake is not known. We explored this question and compared the efficacy of this approach with fish oil supplementation. Methods. Male Wistar rats were divided into the following groups: control (C), fructose (F) (water intake with 10% or 30% fructose for 9 weeks), fish oil (FO), and fructose/fish oil (FFO). Fish oil was supplemented only for the last 33 days of fructose ingestion. Half of the F group remained for additional 8 weeks without fructose ingestion (FR). Results. Fructose ingestion reduced food intake to compensate for the increased energy obtained through water ingestion, independent of fructose concentration. Fish oil supplementation exerted no impact on these parameters, but the removal of fructose from water recovered both ingestion behaviors. Plasma triacylglycerol augmented significantly during the second and third weeks (both fructose groups). Fish oil supplementation did not attenuate the elevation in triacylglycerol caused by fructose intake, but the interruption of sugar consumption normalized this parameter. Conclusion. Elevation in triacylglyceridemia may be recovered by removing fructose from diet, suggesting that it is never too late to repair improper dietary habits.
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Franco CCS, Prates KV, Previate C, Moraes AMP, Matiusso CCI, Miranda RA, de Oliveira JC, Tófolo LP, Martins IP, Barella LF, Ribeiro TA, Malta A, Pavanello A, Francisco FA, Gomes RM, Alves VS, Moreira VM, Rigo KP, Almeida DL, de Sant Anna JR, Prado MAAC, Mathias PCF. Glibenclamide treatment blocks metabolic dysfunctions and improves vagal activity in monosodium glutamate-obese male rats. Endocrine 2017; 56:346-356. [PMID: 28233096 DOI: 10.1007/s12020-017-1263-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 02/06/2017] [Indexed: 12/29/2022]
Abstract
BACKGROUND/AIMS Autonomic nervous system imbalance is associated with metabolic diseases, including diabetes. Glibenclamide is an antidiabetic drug that acts by stimulating insulin secretion from pancreatic beta cells and is widely used in the treatment of type 2 diabetes. Since there is scarce data concerning autonomic nervous system activity and diabetes, the aim of this work was to test whether glibenclamide can improve autonomic nervous system activity and muscarinic acetylcholine receptor function in pre-diabetic obese male rats. METHODS Pre-diabetes was induced by treatment with monosodium L-glutamate in neonatal rats. The monosodium L-glutamate group was treated with glibenclamide (2 mg/kg body weight /day) from weaning to 100 days of age, and the control group was treated with water. Body weight, food intake, Lee index, fasting glucose, insulin levels, homeostasis model assessment of insulin resistance, omeostasis model assessment of β-cell function, and fat tissue accumulation were measured. The vagus and sympathetic nerve electrical activity were recorded. Insulin secretion was measured in isolated islets challenged with glucose, acetylcholine, and the selective muscarinic acetylcholine receptor antagonists by radioimmunoassay technique. RESULTS Glibenclamide treatment prevented the onset of obesity and diminished the retroperitoneal (18%) and epididymal (25%) fat pad tissues. In addition, the glibenclamide treatment also reduced the parasympathetic activity by 28% and glycemia by 20% in monosodium L-glutamate-treated rats. The insulinotropic effect and unaltered cholinergic actions in islets from monosodium L-glutamate groups were increased. CONCLUSION Early glibenclamide treatment prevents monosodium L-glutamate-induced obesity onset by balancing autonomic nervous system activity.
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Affiliation(s)
- Claudinéia C S Franco
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil.
| | - Kelly V Prates
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Carina Previate
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Ana M P Moraes
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Camila C I Matiusso
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Rosiane A Miranda
- Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro/RJ, Brazil
| | - Júlio C de Oliveira
- Institute of Health Sciences, Federal University of Mato Grosso, Sinop, MT, Brazil
| | - Laize P Tófolo
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Isabela P Martins
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Luiz F Barella
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Tatiane A Ribeiro
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Ananda Malta
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Audrei Pavanello
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Flávio A Francisco
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Rodrigo M Gomes
- Department of Physiological Sciences, Federal University of Goiás, Goiânia/GO, Brazil
| | - Vander S Alves
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Veridiana M Moreira
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Késia P Rigo
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Douglas L Almeida
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
| | - Juliane R de Sant Anna
- Laboratory of Mutagenesis & Genetics, Department of Cell Biology and Genetics, State University of Maringá, Maringá, PR, Brazil
| | - Marialba A A C Prado
- Laboratory of Mutagenesis & Genetics, Department of Cell Biology and Genetics, State University of Maringá, Maringá, PR, Brazil
| | - Paulo C F Mathias
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, PR, Brazil
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Impact of Glucocorticoid Excess on Glucose Tolerance: Clinical and Preclinical Evidence. Metabolites 2016; 6:metabo6030024. [PMID: 27527232 PMCID: PMC5041123 DOI: 10.3390/metabo6030024] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 07/28/2016] [Accepted: 07/29/2016] [Indexed: 12/28/2022] Open
Abstract
Glucocorticoids (GCs) are steroid hormones that exert important physiological actions on metabolism. Given that GCs also exert potent immunosuppressive and anti-inflammatory actions, synthetic GCs such as prednisolone and dexamethasone were developed for the treatment of autoimmune- and inflammatory-related diseases. The synthetic GCs are undoubtedly efficient in terms of their therapeutic effects, but are accompanied by significant adverse effects on metabolism, specifically glucose metabolism. Glucose intolerance and reductions in insulin sensitivity are among the major concerns related to GC metabolic side effects, which may ultimately progress to type 2 diabetes mellitus. A number of pre-clinical and clinical studies have aimed to understand the repercussions of GCs on glucose metabolism and the possible mechanisms of GC action. This review intends to summarize the main alterations that occur in liver, skeletal muscle, adipose tissue, and pancreatic islets in the context of GC-induced glucose intolerance. For this, both experimental (animals) and clinical studies were selected and, whenever possible, the main cellular mechanisms involved in such GC-side effects were discussed.
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Miranda RA, Torrezan R, de Oliveira JC, Barella LF, da Silva Franco CC, Lisboa PC, Moura EG, Mathias PCF. HPA axis and vagus nervous function are involved in impaired insulin secretion of MSG-obese rats. J Endocrinol 2016; 230:27-38. [PMID: 27113853 DOI: 10.1530/joe-15-0467] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 04/22/2016] [Indexed: 11/08/2022]
Abstract
Neuroendocrine dysfunctions such as the hyperactivity of the vagus nerve and hypothalamus-pituitary-adrenal (HPA) axis greatly contribute to obesity and hyperinsulinemia; however, little is known about these dysfunctions in the pancreatic β-cells of obese individuals. We used a hypothalamic-obesity model obtained by neonatal treatment with monosodium l-glutamate (MSG) to induce obesity. To assess the role of the HPA axis and vagal tonus in the genesis of hypercorticosteronemia and hyperinsulinemia in an adult MSG-obese rat model, bilateral adrenalectomy (ADX) and subdiaphragmatic vagotomy (VAG) alone or combined surgeries (ADX-VAG) were performed. To study glucose-induced insulin secretion (GIIS) and the cholinergic insulinotropic process, pancreatic islets were incubated with different glucose concentrations with or without oxotremorine-M, a selective agonist of the M3 muscarinic acetylcholine receptor (M3AChR) subtype. Protein expression of M3AChR in pancreatic islets, corticosteronemia, and vagus nerve activity was also evaluated. Surgeries reduced 80% of the body weight gain. Fasting glucose and insulin were reduced both by ADX and ADX-VAG, whereas VAG was only associated with hyperglycemia. The serum insulin post-glucose stimulation was lower in all animals that underwent an operation. Vagal activity was decreased by 50% in ADX rats. In the highest glucose concentration, both surgeries reduced GIIS by 50%, whereas ADX-VAG decreased by 70%. Additionally, M3AChR activity was recovered by the individual surgeries. M3AChR protein expression was reduced by ADX. Both the adrenal gland and vagus nerve contribute to the hyperinsulinemia in the MSG model, although adrenal is more crucial as it appears to modulate parasympathetic activity and M3AChR expression in obesity.
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Affiliation(s)
- Rosiane A Miranda
- Department of BiotechnologyGenetics and Cell Biology, State University of Maringá, Maringá, Brazil Carlos Chagas Filho Biophysics InstituteFederal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rosana Torrezan
- Department of Physiological SciencesState University of Maringá, Maringá, Brazil
| | - Júlio C de Oliveira
- Institute of Health SciencesFederal University of Mato Grosso, Sinop, Brazil
| | - Luiz F Barella
- Molecular Signalling SectionLaboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | | | - Patrícia C Lisboa
- Department of Physiological SciencesRoberto Alcântara Gomes Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Egberto G Moura
- Department of Physiological SciencesRoberto Alcântara Gomes Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paulo C F Mathias
- Department of BiotechnologyGenetics and Cell Biology, State University of Maringá, Maringá, Brazil
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Madhavadas S, Subramanian S. Cognition enhancing effect of the aqueous extract ofCinnamomum zeylanicumon non-transgenic Alzheimer's disease rat model: Biochemical, histological, and behavioural studies. Nutr Neurosci 2016; 20:526-537. [DOI: 10.1080/1028415x.2016.1194593] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Sowmya Madhavadas
- Department of Neurochemistry, National Institute of Mental Health and Neurosciences, Bangalore 560 029, India
| | - Sarada Subramanian
- Department of Neurochemistry, National Institute of Mental Health and Neurosciences, Bangalore 560 029, India
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Barella LF, Miranda RA, Franco CCS, Alves VS, Malta A, Ribeiro TAS, Gravena C, Mathias PCF, de Oliveira JC. Vagus nerve contributes to metabolic syndrome in high-fat diet-fed young and adult rats. Exp Physiol 2014; 100:57-68. [PMID: 25398717 DOI: 10.1113/expphysiol.2014.082982] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 11/05/2014] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Different nerve contributes periods of life are known for their differential sensitivity to interventions, and increased parasympathetic activity affects the development and maintenance of obesity. Thus, we evaluated the involvement of the vagus nerve by performing a vagotomy in young or adult rats that were offered an obesogenic high-fat diet. What is the main finding and its importance? Although the accumulation of adipose tissue decreased in both younger and older groups, the younger rats showed a greater response to the effects of vagotomy in general. In addition to the important role of the parasympathetic activity, we suggest that the vagus nerve contributes to the condition of obesity. Obesity has become a global problem, and this condition develops primarily because of an imbalance between energy intake and expenditure. The high complexity involved in the regulation of energy metabolism results from several factors besides endocrine factors. It has been suggested that obesity could be caused by an imbalance in the autonomous nervous system, which could lead to a condition of high parasympathetic activity in counterpart to low sympathetic tonus. High-fat (HF) diets have been used to induce obesity in experimental animals, and their use in animals leads to insulin resistance, hyperinsulinaemia and high parasympathetic activity, among other disorders. The aim of this work was to evaluate the effects of a vagotomy performed at the initiation of a HF diet at two different stages of life, weaning and adulthood. The vagotomy reduced parasympathetic activity (-32 and -51% in normal fat-fed rats and -43 and -55% in HF diet-fed rats; P < 0.05) and fat depots (-17 and -33%, only in HF diet-fed rats; P < 0.05). High-fat diet-fed rats exhibited fasting hyperinsulinaemia (fivefold higher in young rats and threefold higher in older rats; P < 0.05); however, vagotomy corrected it in younger rats only, and a similar effect was also observed during the glucose tolerance test. The insulin resistance exhibited by the HF diet-fed groups was not altered in the vagotomized rats. We suggest that the vagus nerve, in addition to the important role of parasympathetic activity, contributes to the condition of obesity, and that non-vagal pathways may be involved along with the imbalanced autonomic nervous system.
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Affiliation(s)
- Luiz F Barella
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
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Rafacho A, Ortsäter H, Nadal A, Quesada I. Glucocorticoid treatment and endocrine pancreas function: implications for glucose homeostasis, insulin resistance and diabetes. J Endocrinol 2014; 223:R49-62. [PMID: 25271217 DOI: 10.1530/joe-14-0373] [Citation(s) in RCA: 137] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Glucocorticoids (GCs) are broadly prescribed for numerous pathological conditions because of their anti-inflammatory, antiallergic and immunosuppressive effects, among other actions. Nevertheless, GCs can produce undesired diabetogenic side effects through interactions with the regulation of glucose homeostasis. Under conditions of excess and/or long-term treatment, GCs can induce peripheral insulin resistance (IR) by impairing insulin signalling, which results in reduced glucose disposal and augmented endogenous glucose production. In addition, GCs can promote abdominal obesity, elevate plasma fatty acids and triglycerides, and suppress osteocalcin synthesis in bone tissue. In response to GC-induced peripheral IR and in an attempt to maintain normoglycaemia, pancreatic β-cells undergo several morphofunctional adaptations that result in hyperinsulinaemia. Failure of β-cells to compensate for this situation favours glucose homeostasis disruption, which can result in hyperglycaemia, particularly in susceptible individuals. GC treatment does not only alter pancreatic β-cell function but also affect them by their actions that can lead to hyperglucagonaemia, further contributing to glucose homeostasis imbalance and hyperglycaemia. In addition, the release of other islet hormones, such as somatostatin, amylin and ghrelin, is also affected by GC administration. These undesired GC actions merit further consideration for the design of improved GC therapies without diabetogenic effects. In summary, in this review, we consider the implication of GC treatment on peripheral IR, islet function and glucose homeostasis.
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Affiliation(s)
- Alex Rafacho
- Department of Physiological SciencesCenter of Biological Sciences, Federal University of Santa Catarina (UFSC), 88040-900, Florianópolis, SC, BrazilDepartment of Clinical Science and EducationSödersjukhuset, Karolinska Institutet, SE-11883 Stockholm, SwedenInstitute of Bioengineering and the Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM)Miguel Hernández University, University Avenue s/n, 03202, Elche, Spain
| | - Henrik Ortsäter
- Department of Physiological SciencesCenter of Biological Sciences, Federal University of Santa Catarina (UFSC), 88040-900, Florianópolis, SC, BrazilDepartment of Clinical Science and EducationSödersjukhuset, Karolinska Institutet, SE-11883 Stockholm, SwedenInstitute of Bioengineering and the Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM)Miguel Hernández University, University Avenue s/n, 03202, Elche, Spain
| | - Angel Nadal
- Department of Physiological SciencesCenter of Biological Sciences, Federal University of Santa Catarina (UFSC), 88040-900, Florianópolis, SC, BrazilDepartment of Clinical Science and EducationSödersjukhuset, Karolinska Institutet, SE-11883 Stockholm, SwedenInstitute of Bioengineering and the Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM)Miguel Hernández University, University Avenue s/n, 03202, Elche, Spain
| | - Ivan Quesada
- Department of Physiological SciencesCenter of Biological Sciences, Federal University of Santa Catarina (UFSC), 88040-900, Florianópolis, SC, BrazilDepartment of Clinical Science and EducationSödersjukhuset, Karolinska Institutet, SE-11883 Stockholm, SwedenInstitute of Bioengineering and the Biomedical Research Center in Diabetes and Associated Metabolic Disorders (CIBERDEM)Miguel Hernández University, University Avenue s/n, 03202, Elche, Spain
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dos Santos C, Ferreira FBD, Gonçalves-Neto LM, Taboga SR, Boschero AC, Rafacho A. Age- and gender-related changes in glucose homeostasis in glucocorticoid-treated rats. Can J Physiol Pharmacol 2014; 92:867-78. [DOI: 10.1139/cjpp-2014-0259] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The disruption to glucose homeostasis upon glucocorticoid (GC) treatment in adult male rats has not been fully characterized in older rats or in females. Thus, we evaluated the age- and gender-related changes in glucose homeostasis in GC-treated rats. We injected male and female rats at 3 months and 12 months of age with either dexamethasone (1.0 mg/kg body mass, intraperitoneally) or saline, daily for 5 days. All of the GC-treated rats had decreased body mass and food intake, and adrenal hypotrophy. Increased glycemia was observed in all of the GC-treated groups and only the 3-month-old female rats were not glucose intolerant. Dexamethasone treatment resulted in hyperinsulinemia and hypertriacylglyceridemia in all of the GC-treated rats. The glucose-stimulated insulin secretion (GSIS) was higher in all of the dexamethasone-treated animals, but it was less pronounced in the older animals. The β-cell mass was increased in the younger male rats treated with dexamethasone. We conclude that dexamethasone treatment induces glucose intolerance in both the 3- and 12-month-old male rats as well as hyperinsulinemia and augmented GSIS. Three-month-old female rats are protected from glucose intolerance caused by GC, whereas 12-month-old female rats developed the same complications that were present in 3- and 12-month-old male rats.
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Affiliation(s)
- Cristiane dos Santos
- Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina (UFSC), 88040-900 Florianópolis, Brazil
| | - Francielle Batista D. Ferreira
- Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina (UFSC), 88040-900 Florianópolis, Brazil
| | - Luiz M. Gonçalves-Neto
- Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina (UFSC), 88040-900 Florianópolis, Brazil
| | - Sebastião Roberto Taboga
- Department of Biology, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University (UNESP), São José do Rio Preto, Brazil
| | - Antonio Carlos Boschero
- Department of Structural and Functional Biology, Institute of Biology, and Obesity and Comorbidities Research Center (OCRC), State University of Campinas (UNICAMP), Campinas, Brazil
| | - Alex Rafacho
- Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina (UFSC), 88040-900 Florianópolis, Brazil
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Bighetti BB, d Assis GF, Vieira DC, Violato NM, Cestari TM, Taga R, Bosqueiro JR, Rafacho A. Long-term dexamethasone treatment alters the histomorphology of acinar cells in rat parotid and submandibular glands. Int J Exp Pathol 2014; 95:351-63. [PMID: 25186305 DOI: 10.1111/iep.12092] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 07/21/2014] [Indexed: 11/30/2022] Open
Abstract
Glucocorticoids (GCs) induce insulin resistance (IR), a condition known to alter oral homeostasis. This study investigated the effects of long-term dexamethasone administration on morphofunctional aspects of salivary glands. Male Wistar rats received daily injections of dexamethasone [0.1 mg/kg body weight (b.w.), intraperitoneally] for 10 days (DEX), whereas control rats received saline. Subsequently, glycaemia, insulinaemia, insulin secretion and salivary flow were analysed. The parotid and submandibular glands were collected for histomorphometric evaluation and Western blot experiments. The DEX rats were found to be normoglycaemic, hyperinsulinaemic, insulin resistant and glucose intolerant (P < 0.05). DEX rat islets secreted more insulin in response to glucose (P < 0.05). DEX rats had significant reductions in the masses of the parotid (29%) and submandibular (16%) glands (P < 0.05) that was associated with reduced salivary flux rate. The hypotrophy in both glands observed in the DEX group was associated with marked reduction in the volume of the acinar cells in these glands of 50% and 26% respectively (P < 0.05). The total number of acinar cells was increased in the submandibular glands of the DEX rats (P < 0.05) but not in the parotid glands. The levels of proteins related to insulin and survival signalling in both glands did not differ between the groups. In conclusion, the long-term administration of dexamethasone caused IR, which was associated with significant reductions in both mass and flux rate of the salivary glands. The parotid and submandibular glands exhibited reduced acinar cell volume; however, the submandibular glands displayed acinar hyperplasia, indicating a gland-specific response to GCs. Our data emphasize that GC-based therapies and insulin-resistant states have a negative impact on salivary gland homeostasis.
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Affiliation(s)
- Bruna B Bighetti
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo - USP, Bauru, Brazil
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Cummings BP, Bremer AA, Kieffer TJ, D'Alessio D, Havel PJ. Investigation of the mechanisms contributing to the compensatory increase in insulin secretion during dexamethasone-induced insulin resistance in rhesus macaques. J Endocrinol 2013; 216:207-15. [PMID: 23151361 DOI: 10.1530/joe-12-0459] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Dexamethasone has well-described effects to induce insulin resistance and increase insulin secretion. Herein, we examined potential contributors to the effect of dexamethasone to increase insulin secretion in rhesus macaques. Six male rhesus macaques received daily injections of either saline or dexamethasone (0.25 mg/kg i.m. for 7 days) in random order with 3 weeks between treatments. At the end of the treatment period, animals were fasted overnight and underwent a feeding study the next day, during which blood samples were taken before and for 60 min after a meal in order to assess islet hormone and incretin secretion. Dexamethasone induced marked increases in fasting plasma insulin, glucagon, leptin, and adiponectin concentrations (P<0.05). Surprisingly, the glycemic response after meal ingestion was decreased twofold during dexamethasone treatment (P<0.05). Dexamethasone-treated animals exhibited a significant increase in both insulin and glucose-dependent insulinotropic polypeptide (GIP) secretion during the feeding study (P<0.05). However, glucagon-like peptide-1 secretion was significantly lower in dexamethasone-treated animals compared with controls (P<0.01). Fasting and meal-stimulated pancreatic polypeptide concentrations (an index of the parasympathetic input to the islet) did not differ between saline and dexamethasone treatments. However, the proinsulin:insulin ratio was decreased throughout the feeding study with dexamethasone treatment suggesting an improvement of β-cell function (P<0.05). In conclusion, the maintenance of euglycemia and reduction of postprandial glycemia with short-term dexamethasone treatment appears to be due to the marked elevations of fasting and meal-stimulated insulin secretion. Furthermore, increases in postprandial GIP secretion with dexamethasone treatment appear to contribute to the effect of dexamethasone treatment to increase insulin secretion.
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Affiliation(s)
- Bethany P Cummings
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, One Shields Avenue, Davis, California 95616, USA.
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Ghareeb DA, Hafez HS, Hussien HM, Kabapy NF. Non-alcoholic fatty liver induces insulin resistance and metabolic disorders with development of brain damage and dysfunction. Metab Brain Dis 2011; 26:253-67. [PMID: 21881966 DOI: 10.1007/s11011-011-9261-y] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 08/19/2011] [Indexed: 12/11/2022]
Abstract
In the present study we investigated the effect of the non-alcoholic fatty liver disease (NAFLD) on the alterations in the activity of neurotransmitters catabolizing enzymes and energy catabolising enzymes, prooxidants, endogenous antioxidants and proinflammatory cytokines in brain tissue of NAFLD rats. Rats were intraperitonealy injected with CCl4 solution at a dose of (0.021 mole/Kg, 20 μL, body weight) three times weekly for four weeks. Acetylcholine esterase (AChE), monoamine oxidase (MAO), prooxidant/ antioxidants status, ATPase, lipid profile and glucose level were estimated spectrophotometrically while inflammatory markers; interleukin 6 and tumor necrosis factor alpha (IL6 and TNF-α) and insulin were assessed by ELISA technique. Our results showed that the induced NAFLD and insulin resistance (IR) were accompanied with hyperglycemia and hyperlipidemia and lowered brain glucose level with elevated ATPase activity, prooxidant status (TBARS level, xanthine oxidase and cytochrome 2E1 activities), and inflammatory markers. Through the induction period AChE activity was significantly increased compared to control in blood, liver and brain tissues. Also, MAO activity was significantly increased in both brain and liver tissue but decreased in serum compared with control. These biochemical data were supported with pathophysiological analysis that showed severe neurodegeneration, pyknosis acuolations and cavitations. These observations warrant the reassessment of the conventional concept that the NAFLD with IR progression may induce disturbances in activities of neurotransmitters catabolising enzymes and energy production accompanied with oxidative stress and metabolic disorders, acting as relative risk factors for brain dysfunction and damage with the development of age-associated neurodegenerative diseases such as Alzheimer's disease.
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Affiliation(s)
- Doaa A Ghareeb
- Department of Biochemistry, Faculty of Science, Alexandria University, Moharm Bek, 21511 Alexandria, Egypt
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