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Simões MS, Ames-Sibin AP, Lima EP, Pateis VO, Bersani-Amado CA, Mathias PCF, Peralta RM, Sá-Nakanishi AB, Bracht L, Bracht A, Comar JF. Resveratrol biotransformation and actions on the liver metabolism of healthy and arthritic rats. Life Sci 2022; 310:120991. [PMID: 36162485 DOI: 10.1016/j.lfs.2022.120991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 09/12/2022] [Accepted: 09/20/2022] [Indexed: 10/14/2022]
Abstract
AIMS To investigate the effects of resveratrol on glycogen catabolism and gluconeogenesis in perfused livers of healthy and arthritic rats. The actions of resveratrol-3-O-glucuronide (R3G) and the biotransformation of resveratrol into R3G was further evaluated in the livers. MAIN METHODS arthritis was induced with Freund's adjuvant. Resveratrol at concentrations of 10, 25, 50, 100 and 200 μM and 200 μM R3G were introduced in perfused livers. Resveratrol and metabolites were measured in the outflowing perfusate. Respiration of isolated mitochondria and activity of gluconeogenic enzymes were also evaluated in the livers. KEY FINDINGS resveratrol inhibited glycogen catabolism when infused at concentrations above 50 μM and gluconeogenesis even at 10 μM in both healthy and arthritic rat livers, but more sensitive in these latter. Resveratrol above 100 μM inhibited ADP-stimulated respiration and the activities of NADH- and succinate-oxidases in mitochondria, which were partially responsible for gluconeogenesis inhibition. Pyruvate carboxylase activity was inhibited by 25 μM resveratrol and should inhibit gluconeogenesis already at low concentrations. Resveratrol was significantly metabolized to R3G in healthy rat livers, however, R3G formation was lower in arthritic rat livers. The latter must be in part a consequence of a lower glucose disposal for glucuronidation. When compared to resveratrol, R3G inhibited gluconeogenesis in a lower extension and glycogen catabolism in a higher extension. SIGNIFICANCE the effects of resveratrol and R3G tended to be transitory and existed only when the resveratrol is present in the organ, however, they should be considered because significant serum concentrations of both are found after oral ingestion of resveratrol.
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Affiliation(s)
- Mellina S Simões
- Department of Biochemistry, State University of Maringa, PR, Brazil
| | | | - Emanuele P Lima
- Department of Biochemistry, State University of Maringa, PR, Brazil
| | - Vanesa O Pateis
- Department of Biochemistry, State University of Maringa, PR, Brazil
| | | | - Paulo C F Mathias
- Department of Cellular Biology, State University of Maringa, PR, Brazil
| | - Rosane M Peralta
- Department of Biochemistry, State University of Maringa, PR, Brazil
| | | | - Lívia Bracht
- Department of Biochemistry, State University of Maringa, PR, Brazil
| | - Adelar Bracht
- Department of Biochemistry, State University of Maringa, PR, Brazil
| | - Jurandir F Comar
- Department of Biochemistry, State University of Maringa, PR, Brazil.
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Jazwiec PA, Patterson VS, Ribeiro TA, Yeo E, Kennedy KM, Mathias PCF, Petrik JJ, Sloboda DM. Paternal obesity induces placental hypoxia and sex-specific impairments in placental vascularization and offspring metabolism. Biol Reprod 2022; 107:574-589. [PMID: 35377412 PMCID: PMC9382389 DOI: 10.1093/biolre/ioac066] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 01/31/2022] [Indexed: 12/03/2022] Open
Abstract
Paternal obesity predisposes offspring to metabolic dysfunction, but the underlying mechanisms remain unclear. We investigated whether this metabolic dysfunction is associated with changes in placental vascular development and is fueled by endoplasmic reticulum (ER) stress-mediated changes in fetal hepatic development. We also determined whether paternal obesity indirectly affects the in utero environment by disrupting maternal metabolic adaptations to pregnancy. Male mice fed a standard chow or high fat diet (60%kcal fat) for 8–10 weeks were time-mated with female mice to generate pregnancies and offspring. Glucose tolerance was evaluated in dams at mid-gestation (embryonic day (E) 14.5) and late gestation (E18.5). Hypoxia, angiogenesis, endocrine function, macronutrient transport, and ER stress markers were evaluated in E14.5 and E18.5 placentae and/or fetal livers. Maternal glucose tolerance was assessed at E14.5 and E18.5. Metabolic parameters were assessed in offspring at ~60 days of age. Paternal obesity did not alter maternal glucose tolerance but induced placental hypoxia and altered placental angiogenic markers, with the most pronounced effects in female placentae. Paternal obesity increased ER stress-related protein levels (ATF6 and PERK) in the fetal liver and altered hepatic expression of gluconeogenic factors at E18.5. Offspring of obese fathers were glucose intolerant and had impaired whole-body energy metabolism, with more pronounced effects in female offspring. Metabolic deficits in offspring due to paternal obesity may be mediated by sex-specific changes in placental vessel structure and integrity that contribute to placental hypoxia and may lead to poor fetal oxygenation and impairments in fetal metabolic signaling pathways in the liver.
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Affiliation(s)
- Patrycja A Jazwiec
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton L8S 4L8, Canada
| | - Violet S Patterson
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton L8S 4L8, Canada
| | - Tatiane A Ribeiro
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton L8S 4L8, Canada.,Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton L8S 4L8, Canada.,Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Paraná 87020-900, Brazil
| | - Erica Yeo
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton L8S 4L8, Canada.,Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton L8S 4L8, Canada
| | - Katherine M Kennedy
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton L8S 4L8, Canada.,Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton L8S 4L8, Canada
| | - Paulo C F Mathias
- Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Paraná 87020-900, Brazil
| | - Jim J Petrik
- Department of Biomedical Sciences, University of Guelph, Guelph N1G 2W1, Canada
| | - Deborah M Sloboda
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton L8S 4L8, Canada.,Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton L8S 4L8, Canada.,Department of Pediatrics, McMaster University, Hamilton L8S 4L8, Canada.,Department of Obstetrics and Gynecology, McMaster University, Hamilton L8S 4L8, Canada
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Francisco FA, Saavedra LPJ, Junior MDF, Barra C, Matafome P, Mathias PCF, Gomes RM. Early AGEing and metabolic diseases: is perinatal exposure to glycotoxins programming for adult-life metabolic syndrome? Nutr Rev 2021; 79:13-24. [PMID: 32951053 DOI: 10.1093/nutrit/nuaa074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Perinatal early nutritional disorders are critical for the developmental origins of health and disease. Glycotoxins, or advanced glycation end-products, and their precursors such as the methylglyoxal, which are formed endogenously and commonly found in processed foods and infant formulas, may be associated with acute and long-term metabolic disorders. Besides general aspects of glycotoxins, such as their endogenous production, exogenous sources, and their role in the development of metabolic syndrome, we discuss in this review the sources of perinatal exposure to glycotoxins and their involvement in metabolic programming mechanisms. The role of perinatal glycotoxin exposure in the onset of insulin resistance, central nervous system development, cardiovascular diseases, and early aging also are discussed, as are possible interventions that may prevent or reduce such effects.
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Affiliation(s)
- Flávio A Francisco
- Department of Biotechnology, Genetics, and Cellular Biology, State University of Maringa, Maringa, PR, Brazil
| | - Lucas P J Saavedra
- Department of Biotechnology, Genetics, and Cellular Biology, State University of Maringa, Maringa, PR, Brazil
| | - Marcos D F Junior
- Department of Physiological Sciences, Federal University of Goiás, Goiânia, GO, Brazil
| | - Cátia Barra
- Institute of Physiology and Coimbra Institute of Clinical and Biomedical Research, Faculty of Medicine, and the Center for Innovative Biotechnology and Biomedicine, University of Coimbra; and the Clinical Academic Center of Coimbra, Coimbra, Portugal
| | - Paulo Matafome
- Institute of Physiology and Coimbra Institute of Clinical and Biomedical Research, Faculty of Medicine, and the Center for Innovative Biotechnology and Biomedicine, University of Coimbra; and the Clinical Academic Center of Coimbra, Coimbra, Portugal
| | - Paulo C F Mathias
- Department of Biotechnology, Genetics, and Cellular Biology, State University of Maringa, Maringa, PR, Brazil
| | - Rodrigo M Gomes
- Department of Physiological Sciences, Federal University of Goiás, Goiânia, GO, Brazil
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Gonçalves GD, Walton SL, Gazzard SE, van der Wolde J, Mathias PCF, Moritz KM, Cullen-McEwen LA, Bertram JF. Maternal hypoxia developmentally programs low podocyte endowment in male, but not female offspring. Anat Rec (Hoboken) 2020; 303:2668-2678. [PMID: 31984678 DOI: 10.1002/ar.24369] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 12/02/2019] [Accepted: 12/08/2019] [Indexed: 11/07/2022]
Abstract
Fetal hypoxia is a common complication of pregnancy. We have previously reported that maternal hypoxia in late gestation in mice gives rise to male offspring with reduced nephron number, while females have normal nephron number. Male offspring later develop proteinuria and renal pathology, including glomerular pathology, whereas female offspring are unaffected. Given the central role of podocyte depletion in glomerular and renal pathology, we examined whether maternal hypoxia resulted in low podocyte endowment in offspring. Pregnant CD1 mice were allocated at embryonic day 14.5 to normoxic (21% oxygen) or hypoxic (12% oxygen) conditions. At postnatal day 21, kidneys from mice were immersion fixed, and one mid-hilar slice per kidney was immunostained with antibodies directed against p57 and synaptopodin for podocyte identification. Slices were cleared and imaged with a multiphoton microscope for podometric analysis. Male hypoxic offspring had significantly lower birth weight, nephron number, and podocyte endowment than normoxic male offspring (podocyte number; normoxic 62.86 ± 2.26 podocytes per glomerulus, hypoxic 53.38 ± 2.25; p < .01, mean ± SEM). In contrast, hypoxic female offspring had low birth weight but their nephron and podocyte endowment was the same as normoxic female offspring (podocyte number; normoxic 62.38 ± 1.86 podocytes per glomerulus, hypoxic 61.81 ± 1.80; p = .88). To the best of our knowledge, this is the first report of developmentally programmed low podocyte endowment. Given the well-known association between podocyte depletion in adulthood and glomerular pathology, we postulate that podocyte endowment may place offspring at risk of renal disease in adulthood, and explain the greater vulnerability of male offspring.
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Affiliation(s)
- Gessica D Gonçalves
- Development and Stem Cells Program, Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia.,Biological Science Program, Department of Biotechnology, Genetics and Cellular Biology, State University of Maringá, Maringá, Brazil
| | - Sarah L Walton
- School of Biomedical Sciences and Child Health Research Centre, The University of Queensland, Brisbane, Australia.,Cardiovascular Disease Program, and Department of Physiology, Biomedicine Discovery Institute, Monash University, Melbourne, Australia
| | - Sarah E Gazzard
- Development and Stem Cells Program, Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - James van der Wolde
- Development and Stem Cells Program, Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Paulo C F Mathias
- Biological Science Program, Department of Biotechnology, Genetics and Cellular Biology, State University of Maringá, Maringá, Brazil
| | - Karen M Moritz
- School of Biomedical Sciences and Child Health Research Centre, The University of Queensland, Brisbane, Australia
| | - Luise A Cullen-McEwen
- Development and Stem Cells Program, Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - John F Bertram
- Development and Stem Cells Program, Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
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Prates KV, de Oliveira JC, Malta A, Matiusso CCI, Miranda RA, Ribeiro TA, Francisco FA, Franco CCS, Moreira VM, Alves VS, Torrezan R, Mathias PCF, Barella LF. Sympathetic innervation is essential for metabolic homeostasis and pancreatic beta cell function in adult rats. Mol Cell Endocrinol 2018; 462:119-126. [PMID: 28962894 DOI: 10.1016/j.mce.2017.09.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/24/2017] [Accepted: 09/26/2017] [Indexed: 11/16/2022]
Abstract
Obesity is associated with an imbalance in the activity of the autonomic nervous system (ANS), specifically in the organs involved in energy metabolism. The pancreatic islets are richly innervated by the ANS, which tunes the insulin release due to changes in energy demand. Therefore, changes in the sympathetic input that reach the pancreas can lead to metabolic dysfunctions. To evaluate the role of the sympathetic ends that innervate the pancreas, 60-day-old male Wistar rats were subjected to sympathectomy (SYM) or were sham-operated (SO). At 120 day-old SYM rats exhibited an increase in body weight, fat pads and metabolic dysfunctions. Decreases in the HOMA-IR and reductions in insulin release were observed both in vivo and in vitro. Furthermore, the SYM rats exhibited altered pancreatic islet function in both muscarinic and adrenergic assays and exhibited high protein expression of the alpha-2 adrenergic receptor (α2AR). Because α2AR has been linked to type 2 diabetes, these findings demonstrate the clinical implications of this study.
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Affiliation(s)
- Kelly V Prates
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil.
| | - Júlio C de Oliveira
- Institute of Health Sciences, Federal University of Mato Grosso, Sinop, MT, Brazil
| | - Ananda Malta
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
| | - Camila C I Matiusso
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
| | - Rosiane A Miranda
- Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Tatiane A Ribeiro
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
| | - Flávio A Francisco
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
| | - Claudinéia C S Franco
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
| | - Veridiana M Moreira
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
| | - Vander S Alves
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
| | - Rosana Torrezan
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
| | - Paulo C F Mathias
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Paraná, Brazil
| | - 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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6
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Ibáñez CA, Erthal RP, Ogo FM, Peres MNC, Vieira HR, Conejo C, Tófolo LP, Francisco FA, da Silva Silveira S, Malta A, Pavanello A, Martins IP, da Silva PHO, Jacinto Saavedra LP, Gonçalves GD, Moreira VM, Alves VS, da Silva Franco CC, Previate C, Gomes RM, de Oliveira Venci R, Dias FRS, Armitage JA, Zambrano E, Mathias PCF, Fernandes GSA, Palma-Rigo K. A High Fat Diet during Adolescence in Male Rats Negatively Programs Reproductive and Metabolic Function Which Is Partially Ameliorated by Exercise. Front Physiol 2017; 8:807. [PMID: 29163186 PMCID: PMC5673641 DOI: 10.3389/fphys.2017.00807] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 09/30/2017] [Indexed: 01/21/2023] Open
Abstract
An interaction between obesity, impaired glucose metabolism and sperm function in adults has been observed but it is not known whether exposure to a diet high in fat during the peri-pubertal period can have longstanding programmed effects on reproductive function and gonadal structure. This study examined metabolic and reproductive function in obese rats programmed by exposure to a high fat (HF) diet during adolescence. The effect of physical training (Ex) in ameliorating this phenotype was also assessed. Thirty-day-old male Wistar rats were fed a HF diet (35% lard w/w) for 30 days then subsequently fed a normal fat diet (NF) for a 40-day recovery period. Control animals were fed a NF diet throughout life. At 70 days of life, animals started a low frequency moderate exercise training that lasted 30 days. Control animals remained sedentary (Se). At 100 days of life, biometric, metabolic and reproductive parameters were evaluated. Animals exposed to HF diet showed greater body weight, glucose intolerance, increased fat tissue deposition, reduced VO2max and reduced energy expenditure. Consumption of the HF diet led to an increase in the number of abnormal seminiferous tubule and a reduction in seminiferous epithelium height and seminiferous tubular diameter, which was reversed by moderate exercise. Compared with the NF-Se group, a high fat diet decreased the number of seminiferous tubules in stages VII-VIII and the NF-Ex group showed an increase in stages XI-XIII. HF-Se and NF-Ex animals showed a decreased number of spermatozoa in the cauda epididymis compared with animals from the NF-Se group. Animals exposed to both treatments (HF and Ex) were similar to all the other groups, thus these alterations induced by HF or Ex alone were partially prevented. Physical training reduced fat pad deposition and restored altered reproductive parameters. HF diet consumption during the peri-pubertal period induces long-term changes on metabolism and the reproductive system, but moderate and low frequency physical training is able to recover adipose tissue deposition and reproductive system alterations induced by high fat diet. This study highlights the importance of a balanced diet and continued physical activity during adolescence, with regard to metabolic and reproductive health.
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Affiliation(s)
- Carlos A Ibáñez
- Reproductive Biology Department, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.,Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Rafaela P Erthal
- Laboratory of Toxicology and Reproductive Metabolic Disorders, Department of General Biology, Universidade Estadual de Londrina, Londrina, Brazil
| | - Fernanda M Ogo
- Laboratory of Toxicology and Reproductive Metabolic Disorders, Department of General Biology, Universidade Estadual de Londrina, Londrina, Brazil
| | - Maria N C Peres
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Henrique R Vieira
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Camila Conejo
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Laize P Tófolo
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Flávio A Francisco
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Sandra da Silva Silveira
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Ananda Malta
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Audrei Pavanello
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Isabela P Martins
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Paulo H O da Silva
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Lucas Paulo Jacinto Saavedra
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Gessica D Gonçalves
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Veridiana M Moreira
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Vander S Alves
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Claudinéia C da Silva Franco
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Carina Previate
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Rodrigo M Gomes
- Laboratory of Endocrinology and Metabolism, Department of Physiological Sciences, Universidade Federal de Goiás, Goiânia, Brazil
| | - Renan de Oliveira Venci
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Francielle R S Dias
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - James A Armitage
- School of Medicine, Deakin University, Waurn Ponds, VIC, Australia
| | - Elena Zambrano
- Reproductive Biology Department, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
| | - Paulo C F Mathias
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
| | - Glaura S A Fernandes
- Laboratory of Toxicology and Reproductive Metabolic Disorders, Department of General Biology, Universidade Estadual de Londrina, Londrina, Brazil
| | - Kesia Palma-Rigo
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, Universidade Estadual de Maringá, Maringá, Brazil
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7
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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: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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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] [What about the content of this article? (0)] [Affiliation(s)] [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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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Mathias PCF, Elmhiri G, de Oliveira JC, Delayre-Orthez C, Barella LF, Tófolo LP, Fabricio GS, Chango A, Abdennebi-Najar L. Maternal diet, bioactive molecules, and exercising as reprogramming tools of metabolic programming. Eur J Nutr 2014; 53:711-22. [DOI: 10.1007/s00394-014-0654-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 01/12/2014] [Indexed: 12/21/2022]
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Elmhiri G, Barella LF, Vieau D, Camous S, Mathias PCF, Abdennebi-Najar L. Acute exposure to a precursor of advanced glycation end products induces a dual effect on the rat pancreatic islet function. Int J Endocrinol 2014; 2014:378284. [PMID: 25484898 PMCID: PMC4248554 DOI: 10.1155/2014/378284] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 10/20/2014] [Indexed: 11/18/2022] Open
Abstract
Aim. Chronic diseases are the leading cause of death worldwide. Advanced glycation end products, known as AGEs, are a major risk factor for diabetes onset and maintenance. Methylglyoxal (MG), a highly reactive metabolite of glucose, is a precursor for the generation of endogenous AGEs. Methods. In this current study we incubated in vitro pancreatic islets from adult rats in absence or presence of MG (10 μmol/l) with different concentrations of glucose and different metabolic components (acetylcholine, epinephrine, potassium, forskolin, and leucine). Results. Different effects of MG on insulin secretion were evidenced. In basal glucose stimulation (5.6 mM), MG induced a significant (P < 0.05) increase of insulin secretion. By contrast, in higher glucose concentrations (8.3 mM and 16.7 mM), MG significantly inhibited insulin secretion (P < 0.05). In the presence of potassium, forskolin, and epinephrine, MG enhanced insulin secretion (P < 0.05), while when it was incubated with acetylcholine and leucine, MG resulted in a decrease of insulin secretion (P < 0.05). Conclusion. We suggest that MG modulates the secretion activity of beta-cell depending on its level of stimulation by other metabolic factors. These results provide insights on a dual acute effect of MG on the pancreatic cells.
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Affiliation(s)
- Ghada Elmhiri
- Institut Polytechnique LaSalle Beauvais, EGEAL-UP 2012.10.101., 19 rue Pierre Waguet, 60026 Beauvais Cedex, France
| | - Luiz Felipe Barella
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, 87020-900 Maringá, PR, Brazil
| | - Didier Vieau
- Environnement Périnatal et Croissance (EA4489), Equipe Dénutritions Maternelles Périnatales, SN4, Université de Lille 1, 59655 Villeneuve d'Ascq, France
| | - Sylvaine Camous
- INRA, UMR1198, Biologie du Développement et Reproduction, 78352 Jouy en Josas, France
| | - Paulo C. F. Mathias
- Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, 87020-900 Maringá, PR, Brazil
| | - Latifa Abdennebi-Najar
- Institut Polytechnique LaSalle Beauvais, EGEAL-UP 2012.10.101., 19 rue Pierre Waguet, 60026 Beauvais Cedex, France
- *Latifa Abdennebi-Najar:
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12
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Miranda RA, Agostinho AR, Trevenzoli IH, Barella LF, Franco CCS, Trombini AB, Malta A, Gravena C, Torrezan R, Mathias PCF, de Oliveira JC. Insulin Oversecretion in MSG-Obese Rats is Related to Alterations in Cholinergic Muscarinic Receptor Subtypes in Pancreatic Islets. Cell Physiol Biochem 2014; 33:1075-86. [DOI: 10.1159/000358677] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2014] [Indexed: 11/19/2022] Open
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Gravena C, Andreazzi AE, Mecabo FT, Grassiolli S, Scantamburlo VM, Mathias PCF. Protein restriction during lactation alters the autonomic nervous system control on glucose-induced insulin secretion in adult rats. Nutr Neurosci 2013; 10:79-87. [PMID: 17539486 DOI: 10.1080/10284150701308693] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Involvement of autonomic nervous system (ANS) neurotransmitters on insulin secretion in rats submitted to protein malnutrition during lactation was studied. During the first 2/3 of lactation, mothers received a 4% protein diet (LP). Control group received normal diet (23% protein) (NP). After protein restriction, mothers received normal diets. At 81 days rats were submitted to intravenous glucose tolerance tests (ivGTT). Plasma glucose and insulin concentration (PIC) were measured. Glucose-induced insulin secretion (GIIS) was tested in pancreatic islets. Fasting normoglycemia and hypoinsulinemia were observed in LP rats. Glucose intolerance and low PIC in LP group were detected during ivGTT. Acetylcholine (Ach) or blockage of alpha-adrenoceptors induced high PIC increment in LP rats; atropine or stimulation of alpha-adrenoceptors did not change PIC. Insulin secretion of LP rat islets showed low glucose and carbachol responses. Epinephrine-inhibited GIIS in both islet groups. Hypoinsulinemia observed in lactation-malnourished rats might be caused by alterations in GIIS regulation, including ANS modulation.
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Affiliation(s)
- Clarice Gravena
- Department of Cell Biology and Genetics, State University of Maringá, 87020-900 Maringá, PR, Brazil
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Camargo RL, Torrezan R, de Oliveira JC, Branco RCS, Barella LF, Grassiolli S, Gravena C, Mathias PCF. An increase in glucose concentration in the lateral ventricles of the brain induces changes in autonomic nervous system activity. Neurol Res 2013; 35:15-21. [PMID: 23317794 DOI: 10.1179/1743132812y.0000000112] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
OBJECTIVE Changes in glucose levels mobilize a neuroendocrine response that prevents or corrects glycemia. The hypothalamus is the main area of the brain that regulates glycemic homeostasis. Metabolic diseases, such as obesity and diabetes, are related to imbalance of this control. The modulation of autonomic nervous system (ANS) activity is mediated by neuronal hypothalamic pathways. In the present work, we investigate whether glucose concentration in the hypothalamic area changes ANS activity. METHODS Glucose was administered intracerebroventricularly to 90-day-old rats, and samples of blood were collected during brain glucose infusion to measure the blood glucose and insulin levels. The electric activity of the superior vagus nerve and superior sympathetic ganglion was directly registered. RESULTS Glucose 5·6 mM infused in the hypothalamus induced a 67·6% decrease in blood insulin concentration compared to saline infusion (P<0·01); however, no glycemia changes occurred. During glucose 5·6 mM intracerebroventricular infusion, the firing rate of the vagus nerve was decreased 39% and sympathetic nerve activity was increased 177% compared to saline infusion (P<0·01). DISCUSSION Glucose injection into the brain in the hypothalamic area modulates glucose homeostasis, which might be mediated by the sensitivity of the hypothalamic area to local changes in glucose concentration. We suggest that gluconeurons in the hypothalamus contribute to the control of glycemia through ANS activity.
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Affiliation(s)
- R L Camargo
- Laboratory of Secretion Cell Biology, Department of Cell Biology and Genetics, State University of Maringá, Brazil
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15
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de Oliveira JC, Scomparin DX, Andreazzi AE, Branco RCS, Martins AG, Gravena C, Grassiolli S, Rinaldi W, Barbosa FB, Mathias PCF. Metabolic imprinting by maternal protein malnourishment impairs vagal activity in adult rats. J Neuroendocrinol 2011; 23:148-57. [PMID: 21091554 DOI: 10.1111/j.1365-2826.2010.02095.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Protein restriction during lactation has been suggested to diminish parasympathetic activity, whereas sympathetic activity is enhanced in adult rats. The present study analyses whether dysfunction of the autonomic nervous system is involved in the impairment of insulin secretion from perinatally undernourished rats. Male neonates were reared by mothers fed a low- (4%) protein (LP group) or normal- (23%) protein diet (NP group). At 81 days of age, LP rats showed less body mass than NP rats (318 ± 4 g versus 370 ± 5 g) (P < 0.001). Fat tissue accumulation decreased in LP [0.8 ± 0.03 g/100 g body weight (BW)] compared to NP rats (1.1 ± 0.04 g/100 g BW) (P < 0.001). LP were glucose-intolerant as registered by the area under the curve of an i.v. glucose tolerance test (37 ± 3) compared to NP rats (29 ± 2) (P < 0.05); however, LP animals showed fasting normoglycaemia (LP, 5.0 ± 0.1; NP, 4.9 ± 0.03 mm) and hypoinsulinaemia (LP, 0.10 ± 0.02 ng/ml; NP, 0.17 ± 0.02 ng/ml). LP also showed glucose tissue uptake 60% higher than NP rats (P < 0.05). Vagus firing rate from LP was lower (7.1 ± 0.8 spikes/5 s) than that in NP rats (12.3 ± 0.7 spikes/5 s) (P < 0.001); however, there was no difference in sympathetic nervous activity. The cholinergic insulinotrophic effect was lower in pancreatic islets from LP (0.07 ± 0.01 ng/min/islet) than in NP rats (0.3 ± 0.06 ng/min/islet), whereas the levels of adrenaline-mediated inhibition of glucose-induced insulin release were similar. Perinatal protein restriction inhibited the activity of the vagus nerve, thus reducing the insulinotrophic effect of parasympathetic pathways on pancreatic β-cells, which inhibit insulin secretion.
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Affiliation(s)
- J C de Oliveira
- Laboratory of Secretion Cell Biology, Department of Cell Biology and Genetics, State University of Maringá, Maringá/PR, Brazil
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16
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Andreazzi AE, Scomparin DX, Mesquita FP, Balbo SL, Gravena C, De Oliveira JC, Rinaldi W, Garcia RMG, Grassiolli S, Mathias PCF. Swimming exercise at weaning improves glycemic control and inhibits the onset of monosodium L-glutamate-obesity in mice. J Endocrinol 2009; 201:351-9. [PMID: 19297408 DOI: 10.1677/joe-08-0312] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Swimming exercises by weaning pups inhibited hypothalamic obesity onset and recovered sympathoadrenal axis activity, but this was not observed when exercise training was applied to young adult mice. However, the mechanisms producing this improved metabolism are still not fully understood. Low-intensity swimming training started at an early age and was undertaken to observe glycemic control in hypothalamic-obese mice produced by neonatal treatment with monosodium l-glutamate (MSG). Whereas MSG and control mice swam for 15 min/day, 3 days a week, from the weaning stage up to 90 days old, sedentary MSG and normal mice did not exercise at all. After 14 h of fasting, animals were killed at 90 days of age. Perigonadal fat accumulation was measured to estimate obesity. Fasting blood glucose and insulin concentrations were also measured. Fresh isolated pancreatic islets were used to test glucose-induced insulin release and total catecholamine from the adrenal glands was measured. Mice were also submitted to intraperitoneal glucose tolerance test. MSG-obese mice showed fasting hyperglycemia, hyperinsulinemia, and glucose intolerance. Severe reduction of adrenal catecholamines content has also been reported. Besides, the inhibition of fat tissue accretion, exercise caused normalization of insulin blood levels and glycemic control. The pancreatic islets of obese mice, with impaired glucose-induced insulin secretion, were recovered after swimming exercises. Adrenal catecholamine content was increased by swimming. Results show that attenuation of MSG-hypothalamic obesity onset is caused, at least in part, by modulation of sympathoadrenal axis activity imposed by early exercise, which may be associated with subsequent glucose metabolism improvement.
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Affiliation(s)
- A E Andreazzi
- Laboratory of Secretion Cell Biology, Department of Cell Biology and Genetics, State University of Maringá, PR, Brazil
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17
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Torrezan R, Gomes RM, Ferrarese ML, de Melo FBH, Ramos AMD, Mathias PCF, Scomparin DX. [Treatment with isoflavones replaces estradiol effect on the tissue fat accumulation from ovariectomized rats]. Arq Bras Endocrinol Metabol 2008; 52:1489-96. [PMID: 19197458 DOI: 10.1590/s0004-27302008000900013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Accepted: 10/17/2008] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Isoflavones (ISO) present in soybean are named phytoestrogens because they show estrogen effect. The use of isoflavones has beneficial effect in disturbance of post-menopause, which is characterized by ovarian function suppression. Decreasing of estrogen secretion and consequent morphologic and metabolic disarrangements are observed in female hormonal decline. The aim of present work was to investigate the effect of ISO on the fat accretion of uterine endometric tissue, and HDL and glucose blood concentration from ovariectomized rats (OVX). METHODS Female Wistar rats with 60 days-old were submitted a surgery to remove bilaterally the ovarium. After 8-day recovery period the animals were distributed into three groups: sham operate (GC); OVX ISO untreated (GI) and OVX supplemented with ISO (G II). Total uterus mass, uterus fat and retroperitoneal fat pad, were removed, washed and weighted. Samples of uterus were histological processed to measure endometrium thickness. Blood samples were also collected to analyze the concentration of HDL and glucose. The OVX caused endometric atrophy, decrease of uterus weight and HDL reduction. The treatment with ISO provoked decrease of uterine and retroperitoneal fat pad. HDL increase and glycemia reduction were also observed. However, there was no uterotrophic effect. CONCLUSIONS ISO treatment causes decrease in tissue fat accretion from ovariectomized rats.
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Affiliation(s)
- Rosana Torrezan
- Departamento de Ciências Morfofisiológicas, Centro de Ciências Biológicas, Universidade Estadual de Maringá, Maringá, PR, Brazil
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Paes AMA, Carniatto SR, Francisco FA, Brito NA, Mathias PCF. Acetylcholinesterase activity changes on visceral organs of VMH lesion-induced obese rats. Int J Neurosci 2007; 116:1295-302. [PMID: 17000530 DOI: 10.1080/00207450600920910] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
It is accepted that the tone of the parasympathetic nervous system increases after VMH lesion, whereas the sympathetic tone decreases. To reinforce investigations over outcomes from disturbances of the hypothalamic neuronal systems on peripheral autonomic nerve activity this study determined the acetylcholinesterase (AchE) activity in visceral organs, known as vagal targets, from VMH-lesioned obese rats. It was found that AchE activity was significantly increased in liver, pancreas, and stomach from these animals. However, it was not changed in kidneys, being decreased in spleen. The results suggest that AchE activity is enhanced in vagus innervated tissues to following up the unbalance of the autonomic nervous system as observed in VMH lesion-induced obesity.
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Affiliation(s)
- Antonio M A Paes
- Laboratory of Physiology, Department of Physiological Sciences, Federal University of Maranhão, São Luís, MA, Brazil.
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19
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Scomparin DX, Grassiolli S, Marçal AC, Gravena C, Andreazzi AE, Mathias PCF. Swim training applied at early age is critical to adrenal medulla catecholamine content and to attenuate monosodium l-glutamate-obesity onset in mice. Life Sci 2006; 79:2151-6. [PMID: 16934841 DOI: 10.1016/j.lfs.2006.07.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2006] [Revised: 06/30/2006] [Accepted: 07/11/2006] [Indexed: 10/24/2022]
Abstract
Exercise has been recommended as a remedy against a worldwide obesity epidemic; however, the onset of excessive weight gain is not fully understood, nor are the effects of exercise on body weight control. Activity deficits of the sympathetic nervous system, including the sympathoadrenal axis, have been suggested to contribute to high fat accumulation in obesity. In the present work, swim training was used to observe fat accumulation and adrenal catecholamine stocks in hypothalamic-obese mice produced by neonatal treatment with monosodium L-glutamate (MSG). MSG-treated and normal mice swam for 15 min/day, 3 days a week, from weaning up to 90 days old (EXE 21-90); from weaning up to 50 days old (EXE 21-50) and from 60 up to 90 days old (EXE 60-90). Sedentary MSG and normal mice (SED groups) did not exercise at all. Animals were sacrificed at 90 days of age. MSG treatment induced obesity, demonstrated by a 43.08% increase in epididymal fat pad weight; these adult obese mice presented 27.7% less catecholamine stocks in their adrenal glands than untreated mice (p<0.001). Exercise reduced fat accumulation and increased adrenal catecholamine content in EXE 21-90 groups. These effects were more pronounced in MSG-mice than in normal ones. Halting the exercise (EXE 21-50 groups) still changed fat accretion and catecholamine stocks; however, no effects were recorded in the EXE 60-90 groups. We conclude that metabolic changes imposed by early exercise, leading to an attenuation of MSG-hypothalamic obesity onset, are at least in part due to sympathoadrenal activity modulation.
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Affiliation(s)
- D X Scomparin
- Laboratory of Secretion Cell Biology, Department of Cell Biology and Genetics, State University of Maringá, Av. Colombo 5790, Bloco H-67, S/019, 87020-900 Maringá PR Brazil
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20
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Miguel JC, Patterson S, Abdel-Wahab YHA, Mathias PCF, Flatt PR. Time-correlation between membrane depolarization and intracellular calcium in insulin secreting BRIN-BD11 cells: studies using FLIPR. Cell Calcium 2004; 36:43-50. [PMID: 15126055 DOI: 10.1016/j.ceca.2003.11.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2003] [Revised: 11/20/2003] [Accepted: 11/25/2003] [Indexed: 10/26/2022]
Abstract
Cytoplasmic Ca(2+) ([Ca(2+)](i)) and membrane potential changes were measured in clonal pancreatic beta cells using a fluorimetric imaging plate reader (FLIPR). KCl (30 mM) produced a fast membrane depolarization immediately followed by increase of [Ca(2+)](i) in BRIN-BD11 cells. l-Alanine (10 mM) but not l-arginine (10 mM) mimicked the KCl profile and also produced a fast membrane depolarization and elevation of [Ca(2+)](i). Conversely, a rise in glucose from 5.6 mM to 11.1 or 16.7 mM induced rapid membrane depolarization, followed by a slower and delayed increase of [Ca(2+)](i). GLP-1 (20 nM) did not affect membrane potential or [Ca(2+)](i). In contrast, acetylcholine (ACh, 100 microM) induced fast membrane depolarization immediately followed by a modest [Ca(2+)](i) increase. When extracellular Ca(2+) was buffered with EGTA, ACh mobilized intracellular calcium stores and the [Ca(2+)](i) increase was reduced by 2-aminoethoxydiphenyl borate but not by dantrolene, indicating the involvement of inositol triphosphate receptors (InsP(3)R). It is concluded that membrane depolarization of beta cells by glucose stimulation is not immediately followed by elevation of [Ca(2+)](i) and other metabolic events are involved in glucose induced stimulus-secretion coupling. It is also suggested that ACh mobilizes intracellular Ca(2+) through store operated InsP(3)R.
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Affiliation(s)
- João C Miguel
- School of Biomedical Sciences, University of Ulster, Coleraine, Co. Londonderry, Northern Ireland BT52 1SA, UK.
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Souza KLA, Elsner M, Mathias PCF, Lenzen S, Tiedge M. Cytokines activate genes of the endocytotic pathway in insulin-producing RINm5F cells. Diabetologia 2004; 47:1292-1302. [PMID: 15248046 DOI: 10.1007/s00125-004-1435-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2004] [Accepted: 05/06/2004] [Indexed: 12/25/2022]
Abstract
AIMS/HYPOTHESIS Cytokines are important humoral mediators of beta cell destruction in autoimmune diabetes. The aim of this study was to identify novel cytokine-induced genes in insulin-producing RINm5F cells, which may contribute to beta cell death or survival. METHODS A global gene expression profile in cytokine-exposed insulin-producing RINm5F cells was achieved by automated restriction fragment differential display PCR. The expression of selected candidate genes was confirmed by real-time RT-PCR analysis. RESULTS Exposure of RINm5F cells to IL-1beta or to a cytokine mixture (IL-1beta, TNF-alpha, IFN-gamma) for 6 h resulted in the differential expression of a functional gene cluster. Apart from the well-known up-regulation of the cytokine-responsive genes iNOS, NF-kappaB, MnSOD and Hsp70, several genes that belong to the functional cluster of the endocytotic pathway were identified. These endocytotic genes comprised: clathrin, megalin, synaptotagmin and calcineurin, which were up-regulated by IL-1beta or the cytokine mixture. In contrast, the expression of the calcineurin inhibitor CAIN and of the GDP/GTP exchange protein Rab3 was down-regulated by cytokines. Other up-regulated cytokine-responsive genes were: agrin, murine adherent macrophage protein mRNA ( MAMA) and transport-associated protein ( TAP1/MTP), whereas the plasma membrane calcium ATPase ( PMCA) 2 and PMCA 3 genes were down-regulated by cytokines. CONCLUSIONS/INTERPRETATION Our results indicate that genes of the endocytotic pathway are regulated by pro-inflammatory cytokines. This might affect the density of cytokine receptors at the beta cell surface and concomitantly the sensitivity of the cells to cytokine toxicity. A better understanding of the functional cross-talk between endocytotic and cytokine signalling pathways could further the development of novel strategies to protect pancreatic beta cells against toxic effects of pro-inflammatory cytokines.
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Affiliation(s)
- K L A Souza
- Institute of Clinical Biochemistry, Hanover Medical School, 30623, Hanover, Germany
- Department of Cell Biology and Genetics, University of Maringá, Maringá, Brazil
| | - M Elsner
- Institute of Clinical Biochemistry, Hanover Medical School, 30623, Hanover, Germany
| | - P C F Mathias
- Department of Cell Biology and Genetics, University of Maringá, Maringá, Brazil
| | - S Lenzen
- Institute of Clinical Biochemistry, Hanover Medical School, 30623, Hanover, Germany
| | - M Tiedge
- Institute of Clinical Biochemistry, Hanover Medical School, 30623, Hanover, Germany.
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22
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Martins ACP, Souza KLA, Shio MT, Mathias PCF, Lelkes PI, Garcia RMG. Adrenal medullary function and expression of catecholamine-synthesizing enzymes in mice with hypothalamic obesity. Life Sci 2004; 74:3211-22. [PMID: 15094322 DOI: 10.1016/j.lfs.2003.10.034] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2003] [Accepted: 10/14/2003] [Indexed: 12/17/2022]
Abstract
The mechanisms underlying the onset of obesity are complex and not completely understood. An imbalance of autonomic nervous system has been proposed to be a major cause of great fat deposits accumulation in hypothalamic obesity models. In this work we therefore investigated the adrenal chromaffin cells in monosodium glutamate (MSG)-treated obese female mice. Newborn mice were injected daily with MSG (4 mg/g body weight) or saline (controls) during the first five days of life and studied at 90 days of age. The adrenal catecholamine content was 56.0% lower in the obese group when compared to lean controls (P < 0.0001). Using isolated adrenal medulla we observed no difference in basal catecholamine secretion percentile between obese and lean animals. However, the percentile of catecholamine secretion stimulated by high K+ concentration was lower in the obese group. There was a decrease in the tyrosine hydroxylase enzyme expression (57.3%, P < 0.004) in adrenal glands of obese mice. Interestingly, the expression of dopamine beta-hydroxylase was also reduced (47.0%, P < 0.005). Phenylethanolamine N-methyltransferase expression was not affected. Our results show that in the MSG model, obesity status is associated with a defective adrenal chromaffin cell function. We conclude that in MSG obesity the low total catecholamine content is directly related to a decrease of key catecholamine-synthesizing enzymes, which by its turn may lead to a defective catecholamine secretion.
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Affiliation(s)
- Andréia C P Martins
- Department of Cell Biology and Genetics, State University of Maringá, Maringá, PR, Brazil
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23
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Miguel JC, Abdel-Wahab YHA, Green BD, Mathias PCF, Flatt PR. Cooperative enhancement of insulinotropic action of GLP-1 by acetylcholine uncovers paradoxical inhibitory effect of beta cell muscarinic receptor activation on adenylate cyclase activity. Biochem Pharmacol 2003; 65:283-92. [PMID: 12504804 DOI: 10.1016/s0006-2952(02)01482-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The cooperative effect of glucagon-like peptide 1 (GLP-1) and acetylcholine (ACh) was evaluated in a beta cell line model (BRIN BD11). GLP-1 (20 nM) and ACh (100 microM) increased insulin secretion by 24-47%, whereas in combination there was a further 89% enhancement of insulin release. Overnight culture with 100 ng/mL pertussis toxin (PTX) or 10nM PMA significantly reduced the combined insulinotropic action (P<0.05 and P<0.001, respectively) and the sole stimulatory effects of GLP-1 (PTX treatment; P<0.01) or ACh (PMA treatment; P<0.05). Under control conditions, ACh (50nM-1mM) concentration-dependently inhibited by up to 40% (P<0.001) the 10-fold (P<0.001) elevation of cyclic 3',5'-adenosine monophosphate (cAMP) induced by 20 nM GLP-1. The paradoxical inhibitory action of ACh was abolished by PTX pre-treatment, suggesting involvement of G(i) and/or G(o) G protein alpha subunit. Effects of selective muscarinic receptor antagonists on the concentration-dependent insulinotropic actions of ACh (50 nM-1 mM) on 20 nM GLP-1 induced insulin secretion revealed inhibition by rho-FHHSiD (M3 antagonist, P<0.05), stimulation with pirenzepine (M1 antagonist, P<0.001) and no significant effects of either methoctramine (M2 antagonist) or MT-3 (M4 antagonist). Antagonism of M2, M3 and M4 muscarinic receptor effects with methoctramine (3-100 nM), rho-FHHSiD (3-30 nM) or MT-3 (10-300 nM) did not significantly affect the inhibitory action of ACh on GLP-1 stimulated cAMP production. In contrast, M1 receptor antagonism with pirenzepine (3-30 0nM) resulted in a concentration-dependent decrease in the inhibitory action of ACh on GLP-1 stimulated cAMP production (P<0.001). These data indicate an important functional cooperation between the cholinergic neurotransmitter ACh and the incretin hormone GLP-1 on insulin secretion mediated through the M3 muscarinic receptor subtype. However, the insulinotropic action of ACh was associated with a paradoxical inhibitory effect on GLP-1 stimulated cAMP production, achieved through a novel PTX- and pirenzepine-sensitive M1 muscarinic receptor activated pathway. An imbalance between these pathways may contribute to dysfunctional insulin secretion.
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Affiliation(s)
- João C Miguel
- School of Biomedical Sciences, University of Ulster, Coleraine, Co Londonderry, Northern Ireland, BT52 1SA, UK.
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Balbo SL, Bonfleur ML, Carneiro EM, Amaral MECD, Filiputti E, Mathias PCF. Parasympathetic activity changes insulin response to glucose and neurotransmitters. Diabetes Metab 2002; 28:3S13-7; discussion 3S108-12. [PMID: 12688628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Pancreatic islet isolated from hyperinsulinemic obese rodents showed high glucose sensitivity to stimulation of insulin secretion. Current research evaluates the effect of subdiaphragmatic vagotomy on insulin secretion stimulated by glucose and by a cholinergic agonist carbachol (Cch) in islets isolated from monosodium L-glutamate (MSG)-obese rats. During the first 5 days after birth, MSG was intradermically injected into the cervical area of male Wistar rats (n=26). Control animals were injected with hyperosmotic saline solution (n=26). Vagotomy was performed on 30-day-old rats. On the 90th day, after a 12-h fast, the animals were killed. Pancreatic islets were isolated by collagenase. Batches of islets (n=30) were incubated for 60 min in glucose 2.8-20.0 mM or 0.1-2.0 mM Cch in the presence of glucose 8.3 mM. Released insulin was measured by radioimmunoassay. Insulin secretion stimulated by glucose in islets from MSG-obese rats shifted to the left when compared to that of controls, 63.8+/-3.9 and 42.2+/-2.6 ng/ml/islet/60 min (p<0.001), respectively. Vagotomy decreased by 56% (p<0.001) the secretion induced by all glucose concentrations in islets from MSG-obese rats. In the controls the operation caused a 30% (p<0.01) reduction. Cch stimulated insulin secretion in normal and obese rat islets. Response to obese rat islets was 1/3 less than normal ones (p<0.05). Vagotomy produced a greater potentiation of Cch induced insulin secretion on islets from obese rats. Data suggested that parasympathetic modulation is important to insulin secretion control.
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Affiliation(s)
- S L Balbo
- University of Maringá, Maringá PR Brazil
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Miguel JC, Abdel-Wahab YHA, Mathias PCF, Flatt PR. Muscarinic receptor subtypes mediate stimulatory and paradoxical inhibitory effects on an insulin-secreting beta cell line. Biochim Biophys Acta 2002; 1569:45-50. [PMID: 11853956 DOI: 10.1016/s0304-4165(01)00232-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Acetylcholine (ACh), a major neurotransmitter from the autonomic nervous system, regulates the cholinergic stimulation of insulin secretion, through interactions with muscarinic receptors. The present study has characterised the individual involvement of muscarinic receptor subtypes in ACh-induced insulin secretion, using clonal beta cells and selective muscarinic receptor antagonists. BRIN BD11 cells clearly expressed mRNA encoding m1--m4 whereas m5 was not detected by RT-PCR. Insulin release was measured from BRIN BD11 cells treated with ACh in the presence of muscarinic receptor antagonists at concentrations ranging from 3 nM to 1 microM. 300 nM of muscarinic toxin-3 (M4 antagonist) and 1 microM of methoctramine (M2 antagonist) increased ACh (100 microM) stimulated insulin secretion by 168% and 50% respectively (ANOVA, P<0.05). The antagonists alone had no effect on insulin secretion. In contrast, 300 nM of pirenzepine (M1 antagonist) and 30 nM of hexahydro-sila-difenidol p-fluorohydrochloride (M3 antagonist) inhibited ACh stimulation by 91% and 84% respectively (ANOVA, P<0.01). It is concluded that ACh acts on different receptor subtypes producing both a stimulatory and an inhibitory action on insulin release.
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Affiliation(s)
- João C Miguel
- School of Biomedical Sciences, University of Ulster, Coleraine, Co. Londonderry, UK
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Souza FD, Marchesini JB, Campos ACL, Malafaia O, Monteiro OG, Ribeiro FB, Alves HFP, Siroti FJ, Meister H, Mathias PCF. Efeito da vagotomia troncular em ratos injetados na fase neonatal com glutamato monossódico: estudo biométrico. Acta Cir Bras 2001. [DOI: 10.1590/s0102-86502001000100006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Obesidade hipotalâmica pode ocorrer em humanos e pode ser reproduzida, experimentalmente, por lesão do VMH em ratos. Esta obesidade pode ser revertida por vagotomia troncular (VT), devido à redução da ingestão alimentar e da insulinemia mediada pelo nervo vago. Experimentalmente, a injeção de MSG causa lesão em nível de ARC. O objetivo deste trabalho é avaliar os efeitos do MSG em ratos e se VT os altera. Estudou-se 52 ratos Wistar machos, divididos em dois grupos de 26 animais, um submetido à injeção de MSG na fase neonatal e outro à de solução salina. Aos 30 dias de vida, após nova divisão, obteve-se: grupo MSG, submetido à VT (VTMSG), e outro à laparotomia (LAPMSG); grupo SALINA, submetido à VT (VTSAL), e outro à laparotomia (LAPSAL). Obteve-se peso, CNA e índice de Lee. O consumo alimentar foi obtido dos 30 aos 90 dias de vida. Aos 90 dias, após eutanásia, mensurou-se peso, CNA, índice de Lee e gordura perigonadal. Análise estatística foi realizada pelo "t de Student". Constatou-se que o MSG provoca redução do CNA e aumento do índice de Lee aos 30 dias de vida, e provoca redução do peso e do CNA, aumento do índice de Lee e da gordura perigonadal aos 90 dias e aumento do consumo alimentar dos 30 aos 90 dias de vida. A VT provoca redução do peso, do índice de Lee e da gordura perigonadal, e tendência à redução do CNA no rato injetado com MSG. A VT provoca redução de consumo alimentar nos primeiros 30 dias de pós-operatório, mas com tendência a maior consumo nos 30 dias subseqüentes. Conclui-se que o MSG injetado na fase neonatal provoca aumento do consumo alimentar e da adiposidade e causa redução da estatura e do peso do animal dos 30 aos 90 dias de vida. E que a VT, realizada aos 30 dias de vida, provoca redução do consumo alimentar nos primeiros 30 dias de pós-operatório, da adiposidade e do peso.
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