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Ma N, Zhou J, Zhou Z, Wan B, Lu W. Effects of UBE3A on the insulin resistance in polycystic ovary syndrome through the ubiquitination of AMPK. BMC Endocr Disord 2023; 23:152. [PMID: 37461021 PMCID: PMC10351129 DOI: 10.1186/s12902-023-01400-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 07/03/2023] [Indexed: 07/20/2023] Open
Abstract
BACKGROUND Polycystic ovary syndrome (PCOS) is a reproductive hormonal abnormality and a metabolic disorder, which is frequently associated with insulin resistance (IR). We aim to investigate the potential therapeutic effects of Ubiquitin-protein ligase E3A (UBE3A) on IR in the PCOS rats via Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) activation. METHODS The PCOS and IR rats model was established by dehydroepiandrosterone (DHEA) and high fat diet (HFD) treatment, and the fat rate, glucose tolerance and insulin tolerance were measured. The IR rats numbers were calculated. Besides, the mRNA levels of glucose transporter 4 (GLUT4) and UBE3A were detected by RT-qPCR. Furthermore, the relationship between was demonstrated by co-IP assay. The phosphorylation and ubiquitination of AMPK were analyzed by western blot. RESULTS UBE3A was up-regulated in the PCOS rats. UBE3A knockdown significantly decreased the fat rate, glucose tolerance and insulin tolerance in the PCOS and IR rats. Additionally, the GLUT4 levels were significantly increased in PCOS + IR rats. Besides, after UBE3A knockdown, the IR rats were decreased, the p-IRS1 and p-AKT levels were significantly up-regulated. Furthermore, UBE3A knockdown enhanced phosphorylation of AMPK through decreasing the ubiquitination of AMPK. AMPK knockdown reversed the role of UBE3A knockdown in the PCOS + IR rats. CONCLUSIONS UBE3A knockdown inhibited the IR in PCOS rats through targeting AMPK. Our study indicated that UBE3A might become a potential biological target for the clinical treatment of PCOS.
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Affiliation(s)
- Ning Ma
- Reproductive Medical Center, Hainan Women and Children's Medical Center, No.75 Longkun South Road, Haikou, Hainan, 570206, China
| | - Jing Zhou
- Reproductive Medical Center, Hainan Women and Children's Medical Center, No.75 Longkun South Road, Haikou, Hainan, 570206, China
| | - Zhi Zhou
- Reproductive Medical Center, Hainan Women and Children's Medical Center, No.75 Longkun South Road, Haikou, Hainan, 570206, China
| | - Bangbei Wan
- Reproductive Medical Center, Hainan Women and Children's Medical Center, No.75 Longkun South Road, Haikou, Hainan, 570206, China
| | - Weiying Lu
- Reproductive Medical Center, Hainan Women and Children's Medical Center, No.75 Longkun South Road, Haikou, Hainan, 570206, China.
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2
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Vargas R, Martins IP, Matiusso CCI, Casagrande RA, Zara CB, Huppes de Souza AC, Horst WP, Sieklicki TC, Becker TCA, Lucredi NC, Comar JF, Malta A, Mathias PCDF. Protein restriction during lactation causes transgenerational metabolic dysfunction in adult rat offspring. Front Nutr 2023; 9:1062116. [PMID: 36704794 PMCID: PMC9872122 DOI: 10.3389/fnut.2022.1062116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 12/08/2022] [Indexed: 01/11/2023] Open
Abstract
Introduction Protein restriction during lactation can induce metabolic dysfunctions and has a huge impact on the offspring's phenotype later in its life. We tested whether the effects of a maternal low-protein diet (LP) in rats can be transmitted to the F2 generation and increase their vulnerability to dietary insults in adulthood. Methods Female Wistar rats (F0) were fed either a low-protein diet (LP; 4% protein) during the first 2 weeks of lactation or a normal-protein diet (NP; 23% protein). The female offspring (F1 generation) were maintained on a standard diet throughout the experiment. Once adulthood was reached, female F1 offspring from both groups (i.e., NP-F1 and LP-F1) were bred to proven males, outside the experiment, to produce the F2 generation. Male F2 offspring from both groups (NP-F2 and LP-F2 groups) received a standard diet until 60 days old, at which point they received either a normal fat (NF; 4.5% fat) or a high fat diet (HF; 35% fat) for 30 days. Results At 90 days old, LPNF-F2 offspring had increased lipogenesis and fasting insulinemia compared to NPNF-F2, without alteration in insulin sensitivity. HF diet caused increased gluconeogenesis and displayed glucose intolerance in LPHF-F2 offspring compared to LPNF-F2 offspring. Additionally, the HF diet led to damage to lipid metabolism (such as steatosis grade 3), higher body weight, fat pad stores, and hepatic lipid content. Discussion We concluded that an F0 maternal protein restricted diet during lactation can induce a transgenerational effect on glucose and liver metabolism in the F2 generation, making the offspring's liver more vulnerable to nutritional injury later in life.
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Affiliation(s)
- Rodrigo Vargas
- Department of Biotechnology, Genetics, and Cellular Biology, State University of Maringá, Maringá, Brazil,Health Sciences Center, UniCesumar, Maringá, Brazil,*Correspondence: Rodrigo Vargas,
| | - Isabela Peixoto Martins
- Department of Biotechnology, Genetics, and Cellular Biology, State University of Maringá, Maringá, Brazil,Health Sciences Center, UniCesumar, Maringá, Brazil,Department of Morphological Sciences, State University of Maringá, Maringá, Brazil
| | - Camila Cristina Ianoni Matiusso
- Department of Biotechnology, Genetics, and Cellular Biology, State University of Maringá, Maringá, Brazil,Health Sciences Center, UniCesumar, Maringá, Brazil
| | | | - Camila Benan Zara
- Department of Biotechnology, Genetics, and Cellular Biology, State University of Maringá, Maringá, Brazil
| | | | | | | | | | | | | | - Ananda Malta
- Department of Biotechnology, Genetics, and Cellular Biology, State University of Maringá, Maringá, Brazil
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Burgos-Gamez X, Morales-Castillo P, Fernandez-Mejia C. Maternal adaptations of the pancreas and glucose homeostasis in lactation and after lactation. Mol Cell Endocrinol 2023; 559:111778. [PMID: 36162635 DOI: 10.1016/j.mce.2022.111778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 09/04/2022] [Accepted: 09/13/2022] [Indexed: 02/03/2023]
Abstract
During lactation, the maternal physiology adapts to bear the nutritional requirements of the offspring. The exocrine and endocrine pancreas are central to nutrient handling, promoting digestion and metabolism. In concert with prolactin, insulin is a determinant factor for milk synthesis. The investigation of the pancreas during lactation has been scattered over several periods. The investigations that laid the foundation of lactating pancreatic physiology and glucose homeostasis were conducted in the decades of 1970-1980. With the development of molecular biology, newer studies have revealed the molecular mechanisms involved in the endocrine pancreas during breastfeeding. There has been a surge of information recently about unexpected changes in the pancreas at the end of the lactation period and after weaning. In this review, we aim to gather information on the changes in the pancreas and glucose homeostasis during and after lactation and discuss the outcomes derived from the current discoveries.
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Affiliation(s)
- Xadeni Burgos-Gamez
- Unidad de Genética de la Nutrición. Instituto de Investigaciones Biomédicas. Universidad Nacional Autónoma de México/ Instituto Nacional de Pediatría. Avenida del Iman#1, 4th floor, Mexico City, 04500, Mexico
| | - Paulina Morales-Castillo
- Unidad de Genética de la Nutrición. Instituto de Investigaciones Biomédicas. Universidad Nacional Autónoma de México/ Instituto Nacional de Pediatría. Avenida del Iman#1, 4th floor, Mexico City, 04500, Mexico
| | - Cristina Fernandez-Mejia
- Unidad de Genética de la Nutrición. Instituto de Investigaciones Biomédicas. Universidad Nacional Autónoma de México/ Instituto Nacional de Pediatría. Avenida del Iman#1, 4th floor, Mexico City, 04500, Mexico.
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4
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Zapatería B, Sevillano J, Sánchez-Alonso MG, Limones M, Pizarro-Delgado J, Zuccaro A, Herradón G, Medina-Gómez G, Ramos-Álvarez MP. Deletion of pleiotrophin impairs glucose tolerance and liver metabolism in pregnant mice: Moonlighting role of glycerol kinase. FASEB J 2021; 35:e21911. [PMID: 34551152 DOI: 10.1096/fj.202101181r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/13/2021] [Accepted: 08/24/2021] [Indexed: 01/07/2023]
Abstract
Pleiotrophin is a pleiotropic cytokine that has been demonstrated to have a critical role in regulating energy metabolism, lipid turnover and plasticity of adipose tissue. Here, we hypothesize that this cytokine can be involved in regulatory processes of glucose and lipid homeostasis in the liver during pregnancy. Using 18-days pregnant Ptn-deficient mice, we evaluated the biochemical profile (circulating variables), tissue mRNA expression (qPCR) and protein levels of key enzymes and transcription factors involved in main metabolic pathways. Ptn deletion was associated with a reduction in body weight gain, hyperglycemia and glucose intolerance. Moreover, we observed an impairment in glucose synthesis and degradation during late pregnancy in Ptn-/- mice. Hepatic lipid content was significantly lower (73.6%) in Ptn-/- mice and was associated with a clear reduction in fatty acid, triacylglycerides and cholesterol synthesis. Ptn deletion was accompanying with a diabetogenic state in the mother and a decreased expression of key proteins involved in glucose and lipid uptake and metabolism. Moreover, Ptn-/- pregnant mice have a decreased expression of transcription factors, such as PPAR-α, regulating lipid uptake and glucose and lipid utilization. Furthermore, the augmented expression and nuclear translocation of glycerol kinase, and the decrease in NUR77 protein levels in the knock-out animals can further explain the alterations observed in hepatic glucose metabolism. Our results point out for the first time that pleiotrophin is an important player in maintaining hepatic metabolic homeostasis during late gestation, and further highlighted the moonlighting role of glycerol kinase in the regulation of maternal glucose homeostasis during pregnancy.
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Affiliation(s)
- Begoña Zapatería
- Department of Chemistry and Biochemistry, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Alcorcón, Spain
| | - Julio Sevillano
- Department of Chemistry and Biochemistry, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Alcorcón, Spain
| | - María Gracia Sánchez-Alonso
- Department of Chemistry and Biochemistry, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Alcorcón, Spain
| | - María Limones
- Department of Chemistry and Biochemistry, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Alcorcón, Spain
| | - Javier Pizarro-Delgado
- Department of Chemistry and Biochemistry, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Alcorcón, Spain
| | - Agata Zuccaro
- Department of Chemistry and Biochemistry, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Alcorcón, Spain
| | - Gonzalo Herradón
- Department of Pharmaceutical and Health Sciences, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Alcorcón, Spain
| | - Gema Medina-Gómez
- Department of Basic Sciences of Health, Facultad Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - María Pilar Ramos-Álvarez
- Department of Chemistry and Biochemistry, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Alcorcón, Spain
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Khant Aung Z, Grattan DR, Ladyman SR. Pregnancy-induced adaptation of central sensitivity to leptin and insulin. Mol Cell Endocrinol 2020; 516:110933. [PMID: 32707081 DOI: 10.1016/j.mce.2020.110933] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 06/22/2020] [Accepted: 06/29/2020] [Indexed: 02/07/2023]
Abstract
Pregnancy is a time of increased food intake and fat deposition in the mother, and adaptations of glucose homeostasis to meet the energy demands of the growing fetus. As part of these adaptations, leptin and insulin concentrations increase in the maternal circulation during pregnancy. Central effects of leptin and insulin, however, are counterproductive to pregnancy, as increased action of these hormones in the brain lead to suppression of food intake. To prevent this, it is well documented that pregnancy induces a state of leptin- and insulin-insensitivity in the brain, particularly the hypothalamus, in a range of species. While the mechanisms underlying leptin- or insulin-insensitivity during pregnancy vary between species, there is evidence of reduced transport into the brain, impaired activation of intracellular signalling pathways, including reduced leptin receptor expression, and attenuated activation of downstream neuronal pathways, especially for leptin insensitivity. Pregnancy-induced changes in prolactin, growth hormone and leptin are discussed in terms of their role in mediating this reduced response to leptin and insulin.
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Affiliation(s)
- Z Khant Aung
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, 9016, New Zealand
| | - D R Grattan
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, 9016, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, 1010, New Zealand
| | - S R Ladyman
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, 9016, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, 1010, New Zealand.
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Grattan DR, Ladyman SR. Neurophysiological and cognitive changes in pregnancy. HANDBOOK OF CLINICAL NEUROLOGY 2020; 171:25-55. [PMID: 32736755 DOI: 10.1016/b978-0-444-64239-4.00002-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The hormonal fluctuations in pregnancy drive a wide range of adaptive changes in the maternal brain. These range from specific neurophysiological changes in the patterns of activity of individual neuronal populations, through to complete modification of circuit characteristics leading to fundamental changes in behavior. From a neurologic perspective, the key hormone changes are those of the sex steroids, estradiol and progesterone, secreted first from the ovary and then from the placenta, the adrenal glucocorticoid cortisol, as well as the anterior pituitary peptide hormone prolactin and its pregnancy-specific homolog placental lactogen. All of these hormones are markedly elevated during pregnancy and cross the blood-brain barrier to exert actions on neuronal populations through receptors expressed in specific regions. Many of the hormone-induced changes are in autonomic or homeostatic systems. For example, patterns of oxytocin and prolactin secretion are dramatically altered to support novel physiological functions. Appetite is increased and feedback responses to metabolic hormones such as leptin and insulin are suppressed to promote a positive energy balance. Fundamental physiological systems such as glucose homeostasis and thermoregulation are modified to optimize conditions for fetal development. In addition to these largely autonomic changes, there are also changes in mood, behavior, and higher processes such as cognition. This chapter summarizes the hormonal changes associated with pregnancy and reviews how these changes impact on brain function, drawing on examples from animal research, as well as available information about human pregnancy.
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Affiliation(s)
- David R Grattan
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.
| | - Sharon R Ladyman
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
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Schwartsburd P. Cancer-Induced Reprogramming of Host Glucose Metabolism: "Vicious Cycle" Supporting Cancer Progression. Front Oncol 2019; 9:218. [PMID: 31019893 PMCID: PMC6458235 DOI: 10.3389/fonc.2019.00218] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Accepted: 03/12/2019] [Indexed: 12/21/2022] Open
Abstract
Unrestricted cancer growth requires permanent supply of glucose that can be obtained from cancer-mediated reprogramming of glucose metabolism in the cancer-bearing host. The pathological mechanisms by which cancer cells exert their negative influence on host glucose metabolism are largely unknown. This paper proposes a mechanism of metabolic and hormonal changes that may favor glucose delivery to tumor (not host) cells by creating a cancer-host "vicious cycle" whose prolonged action drives cancer progression and promotes host cachexia. To verify this hypothesis, a feedback model of host-cancer interactions that create the "vicious cycle" via cancer-induced reprogramming of host glucose metabolism is proposed. This model is capable of answering some crucial questions as to how anabolic cancer cells can reprogram the systemic glucose metabolism and why these pathways were not observed in pregnancy. The current paper helps to better understanding a pathogenesis of cancer progression and identify hormonal/metabolic targets for anti-cancer treatment.
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Affiliation(s)
- Polina Schwartsburd
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russia
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8
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Dela Justina V, Dos Passos Junior RR, Bressan AF, Tostes RC, Carneiro FS, Soares TS, Volpato GT, Lima VV, Martin SS, Giachini FR. O-linked N-acetyl-glucosamine deposition in placental proteins varies according to maternal glycemic levels. Life Sci 2018; 205:18-25. [PMID: 29746846 DOI: 10.1016/j.lfs.2018.05.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 05/02/2018] [Accepted: 05/04/2018] [Indexed: 01/25/2023]
Abstract
AIMS Hyperglycemia increases glycosylation with O-linked N-acetyl-glucosamine (O-GlcNAc) contributing to placental dysfunction and fetal growth impairment. Our aim was to determine how O-GlcNAc levels are affected by hyperglycemia and the O-GlcNAc distribution in different placental regions. MAIN METHODS Female Wistar rats were divided into the following groups: severe hyperglycemia (>300 mg/dL; n = 5); mild hyperglycemia (>140 mg/dL, at least than two time points during oral glucose tolerance test; n = 7) or normoglycemia (<120 mg/dL; n = 6). At 21 days of pregnancy, placental tissue was collected and processed for morphometry and immunohistochemistry analyses, or properly stored at -80 °C for protein quantification by western blot. KEY FINDINGS Placental index was increased only in severe hyperglycemic rats. Morphometric analysis showed increased junctional zone and decreased labyrinth region in placentas exclusively from the severe hyperglycemic group. Proteins targeted by O-GlcNAc were detected in all regions, with increased O-GlcNAc levels in the hyperglycemic group compared to control and mild hyperglycemic rats. Proteins in endothelial and trophoblast cells were the main target for O-GlcNAc. Whereas no changes in O-GlcNAc transferase (OGT) expression were detected, O-GlcNAcase (OGA) expression was reduced in placentas from the severe hyperglycemic group and augmented in placentas from the mild hyperglycemic group, compared with their respective control groups. SIGNIFICANCE Placental O-GlcNAc overexpression may contribute to placental dysfunction, as indicated by the placental index. Additionally, morphometric alterations, occurring simultaneously with increased O-GlcNAc accumulation in the placental tissue may contribute to placental dysfunction during hyperglycemia.
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Affiliation(s)
- Vanessa Dela Justina
- Graduate Program in Biological Sciences, Federal University of Goias, Goiania, GO, Brazil; Institute of Biological and Health Sciences, Federal University of Mato Grosso, Barra do Garças, MT, Brazil
| | | | - Alecsander F Bressan
- Institute of Biological and Health Sciences, Federal University of Mato Grosso, Barra do Garças, MT, Brazil
| | - Rita C Tostes
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Fernando S Carneiro
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Thaigra S Soares
- Department of Gynecology and Obstetrics, School of Medicine of Botucatu, Sao Paulo, SP, Brazil
| | - Gustavo T Volpato
- Institute of Biological and Health Sciences, Federal University of Mato Grosso, Barra do Garças, MT, Brazil
| | - Victor Vitorino Lima
- Institute of Biological and Health Sciences, Federal University of Mato Grosso, Barra do Garças, MT, Brazil
| | - Sebastian San Martin
- Biomedical Research Center School of Medicine, Universidad de Valparaiso, Valparaiso, Chile
| | - Fernanda R Giachini
- Graduate Program in Biological Sciences, Federal University of Goias, Goiania, GO, Brazil; Institute of Biological and Health Sciences, Federal University of Mato Grosso, Barra do Garças, MT, Brazil.
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9
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Jensen VF, Mølck AM, Lykkesfeldt J, Bøgh IB. Effect of maternal hypoglycaemia during gestation on materno-foetal nutrient transfer and embryo-foetal development: Evidence from experimental studies focused primarily on the rat. Reprod Toxicol 2018; 77:1-24. [DOI: 10.1016/j.reprotox.2018.01.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 12/07/2017] [Accepted: 01/30/2018] [Indexed: 01/14/2023]
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10
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Ladyman SR, Grattan DR. Region-Specific Suppression of Hypothalamic Responses to Insulin To Adapt to Elevated Maternal Insulin Secretion During Pregnancy. Endocrinology 2017; 158:4257-4269. [PMID: 29029017 DOI: 10.1210/en.2017-00600] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 09/22/2017] [Indexed: 01/22/2023]
Abstract
As part of the adaptation of maternal glucose regulation during pregnancy to ensure glucose provision to the fetus, maternal insulin concentrations become elevated. However, increased central actions of insulin, such as suppression of appetite, would be maladaptive during pregnancy. We hypothesized that central nervous system targets of insulin become less responsive during pregnancy to prevent overstimulation by the increased circulating insulin concentrations. To test this hypothesis, we have measured insulin-induced phosphorylation of Akt (pAkt) in specific hypothalamic nuclei as an index of hypothalamic insulin responsiveness. Despite higher endogenous insulin concentrations following feeding, arcuate nucleus pAkt levels were significantly lower in the pregnant group compared with the nonpregnant group. In response to an intracerebroventricular injection of insulin, insulin-induced pAkt was significantly reduced in the arcuate nucleus and ventromedial nucleus of pregnant rats compared with nonpregnant rats. Similar levels of insulin receptor β and PTEN, a negative regulator of the phosphoinositide 3-kinase/Akt pathway, were detected in hypothalamic areas of nonpregnant and pregnant rats. In the ventromedial nucleus, however, levels of phosphorylated PTEN were significantly lower in pregnancy, suggesting that reduced inactivation of PTEN may contribute to the attenuated insulin signaling in this area during pregnancy. In conclusion, these results demonstrate region-specific changes in responsiveness to insulin in the hypothalamus during pregnancy that may represent an adaptive response to minimize the impact of elevated circulating insulin on the maternal brain.
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Affiliation(s)
- Sharon R Ladyman
- Centre for Neuroendocrinology, University of Otago, New Zealand
- Department of Anatomy, University of Otago, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, New Zealand
| | - David R Grattan
- Centre for Neuroendocrinology, University of Otago, New Zealand
- Department of Anatomy, University of Otago, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, New Zealand
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Marques ADCR, Schiavon FPM, Travassos PB, Eik VF, Godoy G, Schamber CR, Bazotte RB. Evaluation of the impact of orally administered carbohydrates on postprandial blood glucose levels in different pre-clinical models. BRAZ J PHARM SCI 2016. [DOI: 10.1590/s1984-82502016000400021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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12
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Musial B, Fernandez-Twinn DS, Vaughan OR, Ozanne SE, Voshol P, Sferruzzi-Perri AN, Fowden AL. Proximity to Delivery Alters Insulin Sensitivity and Glucose Metabolism in Pregnant Mice. Diabetes 2016; 65:851-60. [PMID: 26740602 PMCID: PMC4876930 DOI: 10.2337/db15-1531] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 12/29/2015] [Indexed: 11/13/2022]
Abstract
In late pregnancy, maternal insulin resistance occurs to support fetal growth, but little is known about insulin-glucose dynamics close to delivery. This study measured insulin sensitivity in mice in late pregnancy at day 16 (D16) and near term at D19. Nonpregnant (NP) and pregnant mice were assessed for metabolite and hormone concentrations, body composition by DEXA, tissue insulin signaling protein abundance by Western blotting, glucose tolerance and utilization, and insulin sensitivity using acute insulin administration and hyperinsulinemic-euglycemic clamps with [(3)H]glucose infusion. Whole-body insulin resistance occurred in D16 pregnant dams in association with basal hyperinsulinemia, insulin-resistant endogenous glucose production, and downregulation of several proteins in hepatic and skeletal muscle insulin signaling pathways relative to NP and D19 values. Insulin resistance was less pronounced at D19, with restoration of NP insulin concentrations, improved hepatic insulin sensitivity, and increased abundance of hepatic insulin signaling proteins. At D16, insulin resistance at whole-body, tissue, and molecular levels will favor fetal glucose acquisition, while improved D19 hepatic insulin sensitivity will conserve glucose for maternal use in anticipation of lactation. Tissue sensitivity to insulin, therefore, alters differentially with proximity to delivery in pregnant mice, with implications for human and other species.
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Affiliation(s)
- Barbara Musial
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, U.K
| | - Denise S Fernandez-Twinn
- University of Cambridge Metabolic Research Laboratories, MRC Metabolic Disease Unit, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, U.K
| | - Owen R Vaughan
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, U.K
| | - Susan E Ozanne
- University of Cambridge Metabolic Research Laboratories, MRC Metabolic Disease Unit, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, U.K
| | - Peter Voshol
- University of Cambridge Metabolic Research Laboratories, MRC Metabolic Disease Unit, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, U.K
| | | | - Abigail L Fowden
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, U.K.
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13
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Abstract
In insulin-resistant states (obesity, pre-diabetes, and type 2 diabetes), hepatic production of glucose and lipid synthesis are heightened in concert, implying that insulin deficiency and insulin excess coexists in this setting. The fact that insulin may be inadequate or excessive at any one point in differing organs and tissues has many biologic ramifications. In this context the concept of metabolic compartmentalization in the liver is offered herein as one perspective of this paradox. In particular, we focus on the hypothesis that insulin resistance accentuates differences in periportal and perivenous hepatocytes, namely periportal glucose production and perivenous lipid synthesis. Subsequently, excessive production of glucose and accumulation of lipids could be expected in the livers of patients with obesity and insulin resistance. Overall, in this review, we provide our integrative perspective regarding how excessive production of glucose in periportal hepatocytes and accumulation of lipids in perivenous hepatocytes interact in insulin resistant states.
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Affiliation(s)
- Roberto B Bazotte
- a Department of Pharmacology and Therapeutics ; State University of Maringá ; Maringá , Paraná , PR Brazil
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14
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Sybuia MF, Guilhermetti M, Mangolim CS, Bazotte RB, Matioli G. Impact of Cyclodextrins on Postprandial Glycemia: Evaluation in Experimental Animal Model Using the Real-Time Continuous Glucose Monitoring System. J Med Food 2015; 18:625-30. [DOI: 10.1089/jmf.2014.0051] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | - Márcio Guilhermetti
- Department of Pharmacology and Therapeutic, State University of Maringá (UEM), Maringá, Paraná, Brazil
| | | | - Roberto Barbosa Bazotte
- Department of Pharmacology and Therapeutic, State University of Maringá (UEM), Maringá, Paraná, Brazil
| | - Graciette Matioli
- Department of Pharmacy, State University of Maringá (UEM), Maringá, Paraná, Brazil
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Ludwig MS, Minguetti-Câmara VC, Heck TG, Scomazzon SP, Nunes PR, Bazotte RB, Homem de Bittencourt PI. Short-term but not long-term hypoglycaemia enhances plasma levels and hepatic expression of HSP72 in insulin-treated rats: an effect associated with increased IL-6 levels but not with IL-10 or TNF-α. Mol Cell Biochem 2014; 397:97-107. [PMID: 25096025 DOI: 10.1007/s11010-014-2176-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 07/24/2014] [Indexed: 01/24/2023]
Abstract
The inducible expression of the 70-kDa heat shock proteins (HSP70) is associated with homeostatically stressful situations. Stresses involving sympathetic nervous system (SNS) activation, including α1-adrenergic agonists and physical exercise, are capable of inducing HSP70 expression and release of the HSP70 inducible form, HSP72. However, whether hypoglycaemia is capable of influencing HSP70 status under a stressful situation such as insulin-induced hypoglycaemia (IIH), which also involves SNS activation, is unsettled. Hence, we decided to investigate whether the predominant signal for HSP70 expression and delivery into the blood comes from either low glucose, high insulin, or both during short-term IIH (STIIH) and long-term IIH (LTIIH). Our data indicated that low glucose level (up to 1.56 ± 0.14 mM), but not insulin, is the triggering factor responsible for a dramatic rise in HSP72 plasma concentrations (from 0.15 ± 0.01 in fed state to 0.77 ± 0.13 ng/mL during hypoglycaemic episodes). This was observed in parallel with up to 7-fold increases in interleukin-6 (IL-6) but not interleukin-10 (IL-10) or tumour necrosis factor-α (TNF-α) at STIIH. Together, the observations may suggest that HSP72 is released under hypoglycaemic conditions as a part of the homeostatic stress response, whereas at long-term, both hypoglycaemia and insulin may influence HSP72 expression in the liver, but not in kidneys. Secreted extracellular HSP72 (eHSP72) may be purely a danger signal to all the tissues of the body for the enhancement of immune and metabolic surveillance state or actively participates in glycaemic control under stressful situations.
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Affiliation(s)
- Mirna Stela Ludwig
- Laboratory of Cellular Physiology, Department of Physiology, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite 500, ICBS, 2° andar, Porto Alegre, RS, 90050-170, Brazil
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Schiavon FPM, Marques ADCR, Carrara MA, de Souza HM, Schamber CR, Curi R, Bazotte RB. Pivotal role of cAMP in the activation of liver glycogen breakdown in high-fat diet fed mice. Life Sci 2014; 109:111-5. [PMID: 24968301 DOI: 10.1016/j.lfs.2014.06.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 06/06/2014] [Accepted: 06/09/2014] [Indexed: 01/14/2023]
Abstract
AIMS Liver glycogen catabolism was evaluated in male Swiss mice fed a high-fat diet rich in saturated fatty acids (HFD) or normal fat diet (NFD) during one week. MAIN METHODS Liver glycogenolysis (LG) and liver glucose production (LGP) were measured either under basal or stimulated conditions (infusion of glycogenolytic agents). Thus, isolated perfused livers from HFD and NFD mice were infused with glycogenolytic agents, i.e., glucagon, epinephrine, phenylephrine, isoproterenol, adenosine-3'-5'-cyclic monophosphate (cAMP), N(6),2'-O-dibutyryl-cAMP (DB-cAMP), 8-bromoadenosine-cAMP (8-Br-cAMP) or N(6)-monobutyryl-cAMP (N6-MB-cAMP). Moreover, glycemia and liver glycogen content were measured. KEY FINDINGS Glycemia, liver glycogen content and basal rate of LGP and LG were not influenced by the HFD. However, LGP and LG were lower (p<0.05) in HFD mice during the infusions of glucagon (1 nM), epinephrine (20 μM) or phenylephrine (20 μM). In contrast, the activation of LGP and LG during the infusion of isoproterenol (20 μM) was not different (HFD vs. NFD). Because glucagon showed the most prominent response, the effect of cAMP, its intracellular mediator, on LGP and LG was investigated. cAMP (150 μM) showed lower activation of LGP and LG in the HFD group. However, the activation of LGP and LG was not influenced by HFD whether DB-cAMP (3 μM), 8-Br-cAMP (3 μM) or N6-MB-cAMP (3 μM) were used. SIGNIFICANCE The activation of LGP and LG depends on the intracellular availability of cAMP. It can be concluded that cAMP played a pivotal role on the activation of LG in high-fat diet fed mice.
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Affiliation(s)
- Fabiana P M Schiavon
- Department of Pharmacology and Therapeutic, State University of Maringá, Maringá, PR 87020-900, Brazil
| | | | | | - Helenir Medri de Souza
- Department of Physiological Sciences, State University of Londrina, Londrina, PR 86051-990, Brazil
| | | | - Rui Curi
- Department of Physiology and Biophysics, University of São Paulo, São Paulo, SP 05508-900, Brazil
| | - Roberto B Bazotte
- Department of Pharmacology and Therapeutic, State University of Maringá, Maringá, PR 87020-900, Brazil.
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