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Mondal S, Bandyopadhyay A. Glucose transporters (GLUTs): Underreported yet crucial molecules in unraveling testicular toxicity. Biochimie 2024; 219:55-62. [PMID: 37967737 DOI: 10.1016/j.biochi.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 11/06/2023] [Accepted: 11/09/2023] [Indexed: 11/17/2023]
Abstract
Glucose transporters (GLUTs) are crucial in maintaining glucose homeostasis and supporting energy production in various tissues, including the testes. This review article delves into the distribution and function of GLUTs in distinct testicular cell types, namely Leydig cells, Sertoli cells, germ cells, and spermatozoa, shedding light on their significance in the context of male reproductive health-an issue of mounting global concern. Furthermore, this article examines the implications of GLUT dysregulation in testicular dysfunction. Altered GLUT expression has been associated with impaired steroidogenesis, spermatogenesis, sperm count, and motility in various animal models. Lastly, the article underscores the potential therapeutic implications of targeting GLUTs concerning testicular toxicity. Insights gleaned from studies in diabetes and cancer suggest that modulating GLUT expression and translocation could present novel strategies for mitigating testicular dysfunction and safeguarding male fertility. In summary, the intricate interplay between GLUTs, glucose metabolism, and testicular health underscores the significance of sustaining testicular glucose homeostasis for male reproductive health. Manipulating GLUTs presents an innovative avenue to address testicular dysfunction, potentially revolutionizing therapeutic strategies to restore male fertility and overall reproductive well-being. Future research in this field holds great promise for advancing male fertility treatments and reproductive health interventions.
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Affiliation(s)
- Shirsha Mondal
- Department of Zoology, Govt. College Dhimarkheda (Rani Durgavati Vishwavidyalaya), Katni, 483 332, Madhya Pradesh, India.
| | - Arindam Bandyopadhyay
- Department of Zoology, University of Allahabad, Prayagraj, 211 002, Uttar Pradesh, India.
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2
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Lipka A, Paukszto Ł, Kennedy VC, Tanner AR, Majewska M, Anthony RV. The Impact of SLC2A8 RNA Interference on Glucose Uptake and the Transcriptome of Human Trophoblast Cells. Cells 2024; 13:391. [PMID: 38474355 PMCID: PMC10930455 DOI: 10.3390/cells13050391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 02/14/2024] [Accepted: 02/22/2024] [Indexed: 03/14/2024] Open
Abstract
While glucose is the primary fuel for fetal growth, the placenta utilizes the majority of glucose taken up from the maternal circulation. Of the facilitative glucose transporters in the placenta, SLC2A8 (GLUT8) is thought to primarily function as an intracellular glucose transporter; however, its function in trophoblast cells has not been determined. To gain insight into the function of SLC2A8 in the placenta, lentiviral-mediated RNA interference (RNAi) was performed in the human first-trimester trophoblast cell line ACH-3P. Non-targeting sequence controls (NTS RNAi; n = 4) and SLC2A8 RNAi (n = 4) infected ACH-3P cells were compared. A 79% reduction in SLC2A8 mRNA concentration was associated with an 11% reduction (p ≤ 0.05) in ACH-3P glucose uptake. NTS RNAi and SLC2A8 RNAi ACH-3P mRNA were subjected to RNAseq, identifying 1525 transcripts that were differentially expressed (|log2FC| > 1 and adjusted p-value < 0.05), with 273 transcripts derived from protein-coding genes, and the change in 10 of these mRNAs was validated by real-time qPCR. Additionally, there were 147 differentially expressed long non-coding RNAs. Functional analyses revealed differentially expressed genes involved in various metabolic pathways associated with cellular respiration, oxidative phosphorylation, and ATP synthesis. Collectively, these data indicate that SLC2A8 deficiency may impact placental uptake of glucose, but that its likely primary function in trophoblast cells is to support cellular respiration. Since the placenta oxidizes the majority of the glucose it takes up to support its own metabolic needs, impairment of SLC2A8 function could set the stage for functional placental insufficiency.
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Affiliation(s)
- Aleksandra Lipka
- Department of Gynecology and Obstetrics, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, 10-045 Olsztyn, Poland
| | - Łukasz Paukszto
- Department of Botany and Nature Protection, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-727 Olsztyn, Poland;
| | - Victoria C. Kennedy
- College of Veterinary Medicine, Colorado State University, Fort Collins, CO 80523, USA; (V.C.K.); (A.R.T.)
| | - Amelia R. Tanner
- College of Veterinary Medicine, Colorado State University, Fort Collins, CO 80523, USA; (V.C.K.); (A.R.T.)
| | - Marta Majewska
- Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury in Olsztyn, 10-082 Olsztyn, Poland;
| | - Russell V. Anthony
- College of Veterinary Medicine, Colorado State University, Fort Collins, CO 80523, USA; (V.C.K.); (A.R.T.)
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3
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Mancini MC, Noland RC, Collier JJ, Burke SJ, Stadler K, Heden TD. Lysosomal glucose sensing and glycophagy in metabolism. Trends Endocrinol Metab 2023; 34:764-777. [PMID: 37633800 PMCID: PMC10592240 DOI: 10.1016/j.tem.2023.07.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 07/27/2023] [Accepted: 07/28/2023] [Indexed: 08/28/2023]
Abstract
Lysosomes are cellular organelles that function to catabolize both extra- and intracellular cargo, act as a platform for nutrient sensing, and represent a core signaling node integrating bioenergetic cues to changes in cellular metabolism. Although lysosomal amino acid and lipid sensing in metabolism has been well characterized, lysosomal glucose sensing and the role of lysosomes in glucose metabolism is unrefined. This review will highlight the role of the lysosome in glucose metabolism with a focus on lysosomal glucose and glycogen sensing, glycophagy, and lysosomal glucose transport and how these processes impact autophagy and energy metabolism. Additionally, the role of lysosomal glucose metabolism in genetic and metabolic diseases will be briefly discussed.
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Affiliation(s)
- Melina C Mancini
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
| | - Robert C Noland
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
| | - J Jason Collier
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
| | - Susan J Burke
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
| | | | - Timothy D Heden
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA.
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4
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Hodge MJ, de Las Heras-Saldana S, Rindfleish SJ, Stephen CP, Pant SD. QTLs and Candidate Genes Associated with Semen Traits in Merino Sheep. Animals (Basel) 2023; 13:2286. [PMID: 37508063 PMCID: PMC10376747 DOI: 10.3390/ani13142286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/06/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023] Open
Abstract
Ram semen traits play a significant role in conception outcomes, which in turn may influence reproductive efficiency and the overall productivity and profitability of sheep enterprises. Since hundreds of ewes may be inseminated from a single ejaculate, it is important to evaluate semen quality prior to use in sheep breeding programs. Given that semen traits have been found to be heritable, genetic variation likely contributes to the variability observed in these traits. Identifying such genetic variants could provide novel insights into the molecular mechanisms underlying variability in semen traits. Therefore, this study aimed to identify quantitative trait loci (QTLs) associated with semen traits in Merino sheep. A genome-wide association study (GWAS) was undertaken using 4506 semen collection records from 246 Merino rams collected between January 2002 and May 2021. The R package RepeatABEL was used to perform a GWAS for semen volume, gross motility, concentration, and percent post-thaw motility. A total of 35 QTLs, located on 16 Ovis aries autosomes (OARs), were significantly associated with either of the four semen traits in this study. A total of 89, 95, 33, and 73 candidate genes were identified, via modified Bonferroni, within the QTLs significantly associated with volume, gross motility, concentration, and percent post-thaw motility, respectively. Among the candidate genes identified, SORD, SH2B1, and NT5E have been previously described to significantly influence spermatogenesis, spermatozoal motility, and high percent post-thaw motility, respectively. Several candidate genes identified could potentially influence ram semen traits based on existing evidence in the literature. As such, validation of these putative candidates may offer the potential to develop future strategies to improve sheep reproductive efficiency. Furthermore, Merino ram semen traits are lowly heritable (0.071-0.139), and thus may be improved by selective breeding.
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Affiliation(s)
- Marnie J Hodge
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
- Apiam Animal Health, Apiam Genetic Services, Dubbo, NSW 2830, Australia
| | - Sara de Las Heras-Saldana
- Animal Genetics and Breeding Unit, a Joint Venture of NSW Department of Primary Industries and University of New England, Armidale, NSW 2351, Australia
| | | | - Cyril P Stephen
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
- Gulbali Institute, Charles Sturt University, Boorooma Street, Wagga Wagga, NSW 2678, Australia
| | - Sameer D Pant
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
- Gulbali Institute, Charles Sturt University, Boorooma Street, Wagga Wagga, NSW 2678, Australia
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5
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Ismail A, Tanasova M. Importance of GLUT Transporters in Disease Diagnosis and Treatment. Int J Mol Sci 2022; 23:8698. [PMID: 35955833 PMCID: PMC9368955 DOI: 10.3390/ijms23158698] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 07/29/2022] [Accepted: 07/30/2022] [Indexed: 12/04/2022] Open
Abstract
Facilitative sugar transporters (GLUTs) are the primary method of sugar uptake in all mammalian cells. There are 14 different types of those transmembrane proteins, but they transport only a handful of substrates, mainly glucose and fructose. This overlap and redundancy contradict the natural tendency of cells to conserve energy and resources, and has led researchers to hypothesize that different GLUTs partake in more metabolic roles than just sugar transport into cells. Understanding those roles will lead to better therapeutics for a wide variety of diseases and disorders. In this review we highlight recent discoveries of the role GLUTs play in different diseases and disease treatments.
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Affiliation(s)
- Abdelrahman Ismail
- Department of Chemistry, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931, USA
| | - Marina Tanasova
- Department of Chemistry, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931, USA
- Health Research Institute, Michigan Technological University, Houghton, MI 49931, USA
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Merges GE, Meier J, Schneider S, Kruse A, Fröbius AC, Kirfel G, Steger K, Arévalo L, Schorle H. Loss of Prm1 leads to defective chromatin protamination, impaired PRM2 processing, reduced sperm motility and subfertility in male mice. Development 2022; 149:275502. [PMID: 35608054 PMCID: PMC9270976 DOI: 10.1242/dev.200330] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 05/12/2022] [Indexed: 12/12/2022]
Abstract
One of the key events during spermiogenesis is the hypercondensation of chromatin by substitution of the majority of histones by protamines. In humans and mice, protamine 1 (PRM1/Prm1) and protamine 2 (PRM2/Prm2) are expressed in a species-specific ratio. Using CRISPR-Cas9-mediated gene editing, we generated Prm1-deficient mice and demonstrated that Prm1+/- mice were subfertile, whereas Prm1-/- mice were infertile. Prm1-/- and Prm2-/- sperm showed high levels of reactive oxygen species-mediated DNA damage and increased histone retention. In contrast, Prm1+/- sperm displayed only moderate DNA damage. The majority of Prm1+/- sperm were CMA3 positive, indicating protamine-deficient chromatin, although this was not the result of increased histone retention in Prm1+/- sperm. However, sperm from Prm1+/- and Prm1-/- mice contained high levels of incompletely processed PRM2. Furthermore, the PRM1:PRM2 ratio was skewed from 1:2 in wild type to 1:5 in Prm1+/- animals. Our results reveal that PRM1 is required for proper PRM2 processing to produce mature PRM2, which, together with PRM1, is able to hypercondense DNA. Thus, the species-specific PRM1:PRM2 ratio has to be precisely controlled in order to retain full fertility.
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Affiliation(s)
- Gina Esther Merges
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Julia Meier
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Simon Schneider
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Alexander Kruse
- Department of Urology, Pediatric Urology and Andrology, Section Molecular Andrology, Biomedical Research Center of the Justus-Liebig University, 35392 Giessen, Germany
| | - Andreas Christian Fröbius
- Department of Urology, Pediatric Urology and Andrology, Section Molecular Andrology, Biomedical Research Center of the Justus-Liebig University, 35392 Giessen, Germany
| | - Gregor Kirfel
- Department of Molecular Cell Biology, Institute for Cell Biology, University of Bonn, 53121 Bonn, Germany
| | - Klaus Steger
- Department of Urology, Pediatric Urology and Andrology, Section Molecular Andrology, Biomedical Research Center of the Justus-Liebig University, 35392 Giessen, Germany
| | - Lena Arévalo
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
| | - Hubert Schorle
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
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7
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Endocrinopathies and Male Infertility. LIFE (BASEL, SWITZERLAND) 2021; 12:life12010010. [PMID: 35054403 PMCID: PMC8779600 DOI: 10.3390/life12010010] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/09/2021] [Accepted: 12/16/2021] [Indexed: 01/22/2023]
Abstract
Male infertility is approaching a concerning prevalence worldwide, and inflicts various impacts on the affected couple. The hormonal assessment is a vital component of male fertility evaluation as endocrine disorders are markedly reversible causatives of male infertility. Precise hormonal regulations are prerequisites to maintain normal male fertility parameters. The core male reproductive event, spermatogenesis, entails adequate testosterone concentration, which is produced via steroidogenesis in the Leydig cells. Physiological levels of both the gonadotropins are needed to achieve normal testicular functions. The hypothalamus-derived gonadotropin-releasing hormone (GnRH) is considered the supreme inducer of the gonadotropins and thereby the subsequent endocrine reproductive events. This hypothalamic–pituitary–gonadal (HPG) axis may be modulated by the thyroidal or adrenal axis and numerous other reproductive and nonreproductive hormones. Disruption of this fine hormonal balance and their crosstalk leads to a spectrum of endocrinopathies, inducing subfertility or infertility in men. This review article will discuss the most essential endocrinopathies associated with male factor infertility to aid precise understanding of the endocrine disruptions-mediated male infertility to encourage further research to reveal the detailed etiology of male infertility and perhaps to develop more customized therapies for endocrinopathy-induced male infertility.
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8
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Mardones L, Muñoz K, Villagrán M. Cell-specific expression of functional glucose transporter 8 in mammary gland. Biochem Biophys Res Commun 2021; 567:125-130. [PMID: 34153681 DOI: 10.1016/j.bbrc.2021.06.037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Accepted: 06/08/2021] [Indexed: 01/13/2023]
Abstract
Differentiated mammary epithelial cells are responsible for milk synthesis during lactation, supporting early postnatal life in mammals. These cells are found in the terminal alveoli of a secretory epithelium, which is surrounded by myoepithelial cells and a stroma rich in fatty tissue. The aim of this study was to explore the cell-specific expression of the glucose transporter GLUT8 in mammary gland and evaluate its functionality for glucose transport, in order to confirm its role in lactose synthesis. Our histological results revealed that GLUT8 is expressed in adipocytes and the epithelial and myoepithelial cells in mammary gland, with a predominant intracellular granular pattern. Colocalization studies of endogenous and green fluorescent protein fused GLUT8 revealed their expressions in lysosome and Golgi, respectively, with Pearson's coefficient correlations of 0.82 ± 0.05 and 0.68 ± 0.16. Functional studies of dileucine to dialanine mutant of GLUT8 showed a fructose-sensitive 2-deoxy glucose uptake at a rate of 83.3 pmoles/(min∗106 cells), 7 folds over empty vector, with a 60 ± 4 and 72 ± 6% decline in 2-deoxy glucose in the presence of 20 and 50 mM fructose, respectively. We concluded that functional GLUT8 is expressed in mammary gland, localizing in mammary epithelial and myoepithelial cells, and adipocytes. In lactation, GLUT8 is expressed mainly in luminal epithelial cells, at the compartments of the endomembrane system. It is necessary to explore the physiological/pathological functions of GLUT8 in mammary gland, including its role in lactation.
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Affiliation(s)
- Lorena Mardones
- Biomedical Sciences Research Laboratory, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile.
| | - Katia Muñoz
- Biomedical Sciences Research Laboratory, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile.
| | - Marcelo Villagrán
- Biomedical Sciences Research Laboratory, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile.
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9
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Alternative Splicing and Cleavage of GLUT8. Mol Cell Biol 2020; 41:MCB.00480-20. [PMID: 33077497 DOI: 10.1128/mcb.00480-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 10/01/2020] [Indexed: 11/20/2022] Open
Abstract
The GLUT (SLC2) family of membrane-associated transporters are described as glucose transporters. However, this family is divided into three classes and, though the regulated transporter activity of class I proteins is becoming better understood, class III protein functions continue to be obscure. We have cataloged the relative expression and splicing of SLC2 mRNA isomers in tumors and normal tissues, with a focus on breast tumors and cell lines. mRNA for the class III protein GLUT8 is the predominant SLC2 species expressed alongside GLUT1 in many tissues, but GLUT8 mRNA exists mostly as an untranslated splice form in tumors. We confirm that GLUT8 is not presented at the cell surface and does not transport glucose directly. However, we reveal a lysosome-dependent reaction that cleaves the GLUT8 protein and releases the carboxy-terminal peptide to a separate vesicle population. Given the localization of GLUT8 at a major metabolic hub (the late endosomal/lysosomal interface) and its regulated cleavage reaction, we evaluated TXNIP-mediated hexosamine homeostasis and speculate that GLUT8 may function as a sensory component of this reaction.
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10
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Effects of reduced glutathione on ram sperm parameters, antioxidant status, mitochondrial activity and the abundance of hexose transporters during liquid storage at 5 ℃. Small Rumin Res 2020. [DOI: 10.1016/j.smallrumres.2020.106139] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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11
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Glucose transporters in adipose tissue, liver, and skeletal muscle in metabolic health and disease. Pflugers Arch 2020; 472:1273-1298. [PMID: 32591906 PMCID: PMC7462924 DOI: 10.1007/s00424-020-02417-x] [Citation(s) in RCA: 193] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 06/01/2020] [Accepted: 06/05/2020] [Indexed: 12/13/2022]
Abstract
A family of facilitative glucose transporters (GLUTs) is involved in regulating tissue-specific glucose uptake and metabolism in the liver, skeletal muscle, and adipose tissue to ensure homeostatic control of blood glucose levels. Reduced glucose transport activity results in aberrant use of energy substrates and is associated with insulin resistance and type 2 diabetes. It is well established that GLUT2, the main regulator of hepatic hexose flux, and GLUT4, the workhorse in insulin- and contraction-stimulated glucose uptake in skeletal muscle, are critical contributors in the control of whole-body glycemia. However, the molecular mechanism how insulin controls glucose transport across membranes and its relation to impaired glycemic control in type 2 diabetes remains not sufficiently understood. An array of circulating metabolites and hormone-like molecules and potential supplementary glucose transporters play roles in fine-tuning glucose flux between the different organs in response to an altered energy demand.
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12
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Kappen C, Kruger C, Jones S, Herion NJ, Salbaum JM. Maternal diet modulates placental nutrient transporter gene expression in a mouse model of diabetic pregnancy. PLoS One 2019; 14:e0224754. [PMID: 31774824 PMCID: PMC6881028 DOI: 10.1371/journal.pone.0224754] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 10/21/2019] [Indexed: 12/30/2022] Open
Abstract
Diabetes in the mother during pregnancy is a risk factor for birth defects and perinatal complications and can affect long-term health of the offspring through developmental programming of susceptibility to metabolic disease. We previously showed that Streptozotocin-induced maternal diabetes in mice is associated with altered cell differentiation and with smaller size of the placenta. Placental size and fetal size were affected by maternal diet in this model, and maternal diet also modulated the risk for neural tube defects. In the present study, we sought to determine the extent to which these effects might be mediated through altered expression of nutrient transporters, specifically glucose and fatty acid transporters in the placenta. Our results demonstrate that expression of several transporters is modulated by both maternal diet and maternal diabetes. Diet was revealed as the more prominent determinant of nutrient transporter expression levels, even in pregnancies with uncontrolled diabetes, consistent with the role of diet in placental and fetal growth. Notably, the largest changes in nutrient transporter expression levels were detected around midgestation time points when the placenta is being formed. These findings place the critical time period for susceptibility to diet exposures earlier than previously appreciated, implying that mechanisms underlying developmental programming can act on placenta formation.
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Affiliation(s)
- Claudia Kappen
- Department of Developmental Biology, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, United States of America
- * E-mail:
| | - Claudia Kruger
- Department of Developmental Biology, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, United States of America
| | - Sydney Jones
- Baton Rouge, Louisiana, United States of America Regulation of Gene Expression Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, United States of America
| | - Nils J. Herion
- Department of Developmental Biology, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, United States of America
- Baton Rouge, Louisiana, United States of America Regulation of Gene Expression Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, United States of America
| | - J. Michael Salbaum
- Baton Rouge, Louisiana, United States of America Regulation of Gene Expression Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, United States of America
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13
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Fan H, Zhou Y, Wen H, Zhang X, Zhang K, Qi X, Xu P, Li Y. Genome-wide identification and characterization of glucose transporter (glut) genes in spotted sea bass (Lateolabrax maculatus) and their regulated hepatic expression during short-term starvation. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2019; 30:217-229. [PMID: 30913477 DOI: 10.1016/j.cbd.2019.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 03/14/2019] [Accepted: 03/16/2019] [Indexed: 12/16/2022]
Abstract
The glucose transporters (GLUTs) are well known for their essential roles in moving the key metabolites, glucose, galactose, fructose and a number of other important substrates in and out of cells. In this study, we identified a total of 21 glut genes in spotted sea bass (Lateolabrax maculatus) through extensive data mining of existing genomic and transcriptomic databases. Glut genes of spotted sea bass were classified into three subfamilies (Class I, Class II and Class III) according to the phylogenetic analysis. Glut genes of spotted sea bass were distributed in 15 out of 24 chromosomes. Deduced gene structure analysis including the secondary structure and the three-dimensional structures, as well as the syntenic analysis further supported their annotations and orthologies. Expression profile in healthy tissues indicated that 9 of 21 glut genes were expressed in liver of spotted sea bass. During short-term starvation, the mRNA expression levels of 3 glut genes (glut2, glut5, and glut10) were significantly up-regulated in liver (P < 0.05), indicating their potential roles in sugar transport and consumption. These findings in our study will facilitate the further evolutionary characterization of glut genes in fish species and provide a theoretical basis for their functional study.
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Affiliation(s)
- Hongying Fan
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao 266003, PR China
| | - Yangyang Zhou
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao 266003, PR China
| | - Haishen Wen
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao 266003, PR China
| | - Xiaoyan Zhang
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao 266003, PR China
| | - Kaiqian Zhang
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao 266003, PR China
| | - Xin Qi
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao 266003, PR China
| | - Peng Xu
- Fujian Collaborative Innovation Centre for Exploitation and Utilization of Marine Biological Resources, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, PR China
| | - Yun Li
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao 266003, PR China.
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14
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Ancey PB, Contat C, Meylan E. Glucose transporters in cancer - from tumor cells to the tumor microenvironment. FEBS J 2018; 285:2926-2943. [PMID: 29893496 DOI: 10.1111/febs.14577] [Citation(s) in RCA: 307] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 05/17/2018] [Accepted: 06/08/2018] [Indexed: 12/18/2022]
Abstract
Solute carriers of the glucose transporter (GLUT) family mediate the first step for cellular glucose usage. The upregulation of GLUTs has been reported in numerous cancer types as a result of perturbation of gene expression or protein relocalization or stabilization. Because they enable to sustain the energy demand required by tumor cells for various biochemical programs, they are promising targets for the development of anticancer strategies. Recently, important biological insights have come from the fine crystal structure determination of several GLUTs; these advances will likely catalyze the development of new selective inhibitory compounds. Furthermore, deregulated glucose metabolism of nontumor cells in the tumor mass is beginning to be appreciated and could have major implications for our understanding of how glucose uptake by specific cell types influences the behavior of neighboring cells in the same microenvironment. In this review, we discuss some of the deregulation mechanisms of glucose transporters, their genetic and pharmacological targeting in cancer, and new functions they may have in nontumor cells of the tumor environment or beyond glucose uptake for glycolysis.
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Affiliation(s)
- Pierre-Benoit Ancey
- Swiss Institute for Experimental Cancer Research, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Switzerland
| | - Caroline Contat
- Swiss Institute for Experimental Cancer Research, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Switzerland
| | - Etienne Meylan
- Swiss Institute for Experimental Cancer Research, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Switzerland
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15
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Jeckel KM, Boyarko AC, Bouma GJ, Winger QA, Anthony RV. Chorionic somatomammotropin impacts early fetal growth and placental gene expression. J Endocrinol 2018; 237:301-310. [PMID: 29661800 PMCID: PMC5953842 DOI: 10.1530/joe-18-0093] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 04/16/2018] [Indexed: 12/16/2022]
Abstract
Several developmental windows, including placentation, must be negotiated to establish and maintain pregnancy. Impaired placental function can lead to preeclampsia and/or intrauterine growth restriction (IUGR), resulting in increased infant mortality and morbidity. It has been hypothesized that chorionic somatomammotropin (CSH) plays a significant role in fetal development, potentially by modifying maternal and fetal metabolism. Recently, using lentiviral-mediated in vivo RNA interference in sheep, we demonstrated significant reductions in near-term (135 days of gestation; dGA) fetal and placental size, and altered fetal liver gene expression, resulting from CSH deficiency. We sought to examine the impact of CSH deficiency on fetal and placental size earlier in gestation (50 dGA), and to examine placental gene expression at 50 and 135 dGA. At 50 dGA, CSH-deficient pregnancies exhibited a 41% reduction (P ≤ 0.05) in uterine vein concentrations of CSH, and significant (P ≤ 0.05) reductions (≈21%) in both fetal body and liver weights. Placentae harvested at 50 and 135 dGA exhibited reductions in IGF1 and IGF2 mRNA concentrations, along with reductions in SLC2A1 and SLC2A3 mRNA. By contrast, mRNA concentrations for various members of the System A, System L and System y+ amino acid transporter families were not significantly impacted. The IUGR observed at the end of the first-third of gestation indicates that the near-term IUGR reported previously, began early in gestation, and may have in part resulted from deficits in the paracrine action of CSH within the placenta. These results provide further compelling evidence for the importance of CSH in the progression and outcome of pregnancy.
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Affiliation(s)
- K M Jeckel
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - A C Boyarko
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - G J Bouma
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Q A Winger
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - R V Anthony
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
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16
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Janzen C, Lei MYY, Jeong ISD, Ganguly A, Sullivan P, Paharkova V, Capodanno G, Nakamura H, Perry A, Shin BC, Lee KW, Devaskar SU. Humanin (HN) and glucose transporter 8 (GLUT8) in pregnancies complicated by intrauterine growth restriction. PLoS One 2018; 13:e0193583. [PMID: 29590129 PMCID: PMC5873989 DOI: 10.1371/journal.pone.0193583] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 02/14/2018] [Indexed: 12/20/2022] Open
Abstract
Background Intrauterine growth restriction (IUGR) results from a lack of nutrients transferred to the developing fetus, particularly oxygen and glucose. Increased expression of the cytoprotective mitochondrial peptide, humanin (HN), and the glucose transporter 8, GLUT8, has been reported under conditions of hypoxic stress. However, the presence and cellular localization of HN and GLUT8 in IUGR-related placental pathology remain unexplored. Thus, we undertook this study to investigate placental expression of HN and GLUT8 in IUGR-affected versus normal pregnancies. Results We found 1) increased HN expression in human IUGR-affected pregnancies on the maternal aspect of the placenta (extravillous trophoblastic (EVT) cytoplasm) compared to control (i.e. appropriate for gestational age) pregnancies, and a concomitant increase in GLUT8 expression in the same compartment, 2) HN and GLUT8 showed a protein-protein interaction by co-immunoprecipitation, 3) elevated HN and GLUT8 levels in vitro under simulated hypoxia in human EVT cells, HTR8/SVneo, and 4) increased HN expression but attenuated GLUT8 expression in vitro under serum deprivation in HTR8/SVneo cells. Conclusions There was elevated HN expression with cytoplasmic localization to EVTs on the maternal aspect of the human placenta affected by IUGR, also associated with increased GLUT8 expression. We found that while hypoxia increased both HN and GLUT8, serum deprivation increased HN expression alone. Also, a protein-protein interaction between HN and GLUT8 suggests that their interaction may fulfill a biologic role that requires interdependency. Future investigations delineating molecular interactions between these proteins are required to fully uncover their role in IUGR-affected pregnancies.
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Affiliation(s)
- Carla Janzen
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- * E-mail:
| | - Margarida Y. Y. Lei
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Il Seok D. Jeong
- Department of Pediatrics, Division of Endocrinology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- Neonatal Research Center of the UCLA Children’s Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Amit Ganguly
- Neonatal Research Center of the UCLA Children’s Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- Department of Pediatrics, Division of Neonatology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Peggy Sullivan
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Vladislava Paharkova
- Department of Pediatrics, Division of Endocrinology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- Neonatal Research Center of the UCLA Children’s Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Gina Capodanno
- Department of Pediatrics, Division of Endocrinology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- Neonatal Research Center of the UCLA Children’s Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Hiromi Nakamura
- Department of Pediatrics, Division of Endocrinology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- Neonatal Research Center of the UCLA Children’s Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Alix Perry
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Bo-Chul Shin
- Neonatal Research Center of the UCLA Children’s Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- Department of Pediatrics, Division of Neonatology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Kuk-Wha Lee
- Department of Pediatrics, Division of Endocrinology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- Neonatal Research Center of the UCLA Children’s Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Sherin U. Devaskar
- Neonatal Research Center of the UCLA Children’s Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- Department of Pediatrics, Division of Neonatology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
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17
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Expression of glucose transporter 8 (GLUT8) in spermatogenesis of adult boar testes. Acta Histochem 2017; 119:632-637. [PMID: 28780960 DOI: 10.1016/j.acthis.2017.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 07/16/2017] [Accepted: 07/24/2017] [Indexed: 11/23/2022]
Abstract
The present study was designed to investigate the glucose transporter 8 (GLUT8) expression and localization in adult boar testis. Localization and expression of GLUT8 were conducted with Western Blotting, immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) methods GLUT8 protein and mRNA were expressed in the boar testes. The results of Western Blotting analysis showed specificity of the antibody for protein of boar testes. The immunohistochemistry results showed that GLUT8 protein mainly localized in spermatocytes, round spermatids and elongated spermatids of the seminiferous tubules in the adult boar testes. And the GLUT8 expression persists during eight stages of boar spermatogenesis. GLUT8 may mainly provide glucose for the later stage of germ cell differentiation in adluminal compartment in adult boar testes. These results suggested that GLUT8 is important for the spermatogenesis in the adult boar testes.
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18
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Heat stress–induced autophagy promotes lactate secretion in cultured immature boar Sertoli cells by inhibiting apoptosis and driving SLC2A3 , LDHA , and SLC16A1 expression. Theriogenology 2017; 87:339-348. [DOI: 10.1016/j.theriogenology.2016.09.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 09/06/2016] [Accepted: 09/07/2016] [Indexed: 01/07/2023]
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19
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Takeda N, Yoshinaga K, Furushima K, Takamune K, Li Z, Abe SI, Aizawa SI, Yamamura KI. Viable offspring obtained from Prm1-deficient sperm in mice. Sci Rep 2016; 6:27409. [PMID: 27250771 PMCID: PMC4890041 DOI: 10.1038/srep27409] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/18/2016] [Indexed: 12/14/2022] Open
Abstract
Protamines are expressed in the spermatid nucleus and allow denser packaging of DNA compared with histones. Disruption of the coding sequence of one allele of either protamine 1 (Prm1) or Prm2 results in failure to produce offspring, although sperm with disrupted Prm1 or Prm2 alleles are produced. Here, we produced Prm1-deficient female chimeric mice carrying Prm1-deficient oocytes. These mice successfully produced Prm1(+/-) male mice. Healthy Prm1(+/-) offspring were then produced by transferring blastocysts obtained via in vitro fertilization using zona-free oocytes and sperm from Prm1(+/-) mice. This result suggests that sperm lacking Prm1 can generate offspring despite being abnormally shaped and having destabilised DNA, decondensed chromatin and a reduction in mitochondrial membrane potential. Nevertheless, these mice showed little derangement of expression profiles.
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Affiliation(s)
- Naoki Takeda
- Division of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, 2-2-1 Honjo, Kumamoto 860-0811, Japan
| | - Kazuya Yoshinaga
- Department of Anatomy, Graduate School of Health Sciences, Kumamoto University, 4-24-1 Kuhonji, Kumamoto 862-0975, Japan
| | - Kenryo Furushima
- Department of Molecular Cell Biology and Molecular Medicine, Institute of Advanced Medicine, Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Japan
| | - Kazufumi Takamune
- Department of Biological Sciences, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan
| | - Zhenghua Li
- Department of Histology and Embryology, Harbin Medical University, Harbin 150081, China
| | - Shin-Ichi Abe
- Kumamoto Health Science University, 325 Izumi-machi, Kita-ku, Kumamoto 861-5598, Japan
| | - Shin-Ichi Aizawa
- Center for Developmental Biology, RIKEN Kobe, 2-2-3 Minatojima Minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Ken-Ichi Yamamura
- Yamamura Project Laboratory, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto 860-0811, Japan
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20
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Tourmente M, Villar-Moya P, Rial E, Roldan ERS. Differences in ATP Generation Via Glycolysis and Oxidative Phosphorylation and Relationships with Sperm Motility in Mouse Species. J Biol Chem 2015; 290:20613-26. [PMID: 26048989 DOI: 10.1074/jbc.m115.664813] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Indexed: 12/20/2022] Open
Abstract
Mouse sperm produce enough ATP to sustain motility by anaerobic glycolysis and respiration. However, previous studies indicated that an active glycolytic pathway is required to achieve normal sperm function and identified glycolysis as the main source of ATP to fuel the motility of mouse sperm. All the available evidence has been gathered from the studies performed using the laboratory mouse. However, comparative studies of closely related mouse species have revealed a wide range of variation in sperm motility and ATP production and that the laboratory mouse has comparatively low values in these traits. In this study, we compared the relative reliance on the usage of glycolysis or oxidative phosphorylation as ATP sources for sperm motility between mouse species that exhibit significantly different sperm performance parameters. We found that the sperm of species with higher oxygen consumption/lactate excretion rate ratios were able to produce higher amounts of ATP, achieving higher swimming velocities. Additionally, we show that the species with higher respiration/glycolysis ratios have a higher degree of dependence upon active oxidative phosphorylation. Moreover, we characterize for the first time two mouse species in which sperm depend on functional oxidative phosphorylation to achieve normal performance. Finally, we discuss that sexual selection could promote adaptations in sperm energetic metabolism tending to increase the usage of a more efficient pathway for the generation of ATP (and faster sperm).
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Affiliation(s)
- Maximiliano Tourmente
- From the Reproductive Ecology and Biology Group, Museo Nacional de Ciencias Naturales (Consejo Superior de Investigaciones Científicas), 28006 Madrid and
| | - Pilar Villar-Moya
- From the Reproductive Ecology and Biology Group, Museo Nacional de Ciencias Naturales (Consejo Superior de Investigaciones Científicas), 28006 Madrid and
| | - Eduardo Rial
- the Mitochondrial Bioenergetics Research Group, Centro de Investigaciones Biológicas (Consejo Superior de Investigaciones Científicas), 28040 Madrid, Spain
| | - Eduardo R S Roldan
- From the Reproductive Ecology and Biology Group, Museo Nacional de Ciencias Naturales (Consejo Superior de Investigaciones Científicas), 28006 Madrid and
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21
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Stewart MJ, Stewart P, Rivera-Posada J. De novo assembly of the transcriptome ofAcanthaster plancitestes. Mol Ecol Resour 2014; 15:953-66. [DOI: 10.1111/1755-0998.12360] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2014] [Revised: 12/04/2014] [Accepted: 12/08/2014] [Indexed: 11/29/2022]
Affiliation(s)
- Michael James Stewart
- Genecology Research Centre; Faculty of Science, Health, Education and Engineering; University of the Sunshine Coast; Maroochydore DC Queensland 4558 Australia
| | - Praphaporn Stewart
- Genecology Research Centre; Faculty of Science, Health, Education and Engineering; University of the Sunshine Coast; Maroochydore DC Queensland 4558 Australia
| | - Jairo Rivera-Posada
- ARC Centre of Excellence for Coral Reefs Studies; James Cook University; Townsville Queensland 4812 Australia
- Australian Institute of Marine Science; PMB No. 3 Townsville Queensland 4810 Australia
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22
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Chauvin T, Xie F, Liu T, Nicora CD, Yang F, Camp DG, Smith RD, Roberts KP. A systematic analysis of a deep mouse epididymal sperm proteome. Biol Reprod 2012; 87:141. [PMID: 23115268 DOI: 10.1095/biolreprod.112.104208] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Spermatozoa are highly specialized cells that, when mature, are capable of navigating the female reproductive tract and fertilizing an oocyte. The sperm cell is thought to be largely quiescent in terms of transcriptional and translational activity. As a result, once it has left the male reproductive tract, the sperm cell is essentially operating with a static population of proteins. It therefore is theoretically possible to understand the protein networks contained in a sperm cell and to deduce its cellular function capabilities. To this end, we performed a proteomic analysis of mouse sperm isolated from the cauda epididymis and confidently identified 2850 proteins, which to our knowledge is the most comprehensive sperm proteome for any species reported to date. These proteins comprise many complete cellular pathways, including those for energy production via glycolysis, beta-oxidation and oxidative phosphorylation, protein folding and transport, and cell signaling systems. This proteome should prove a useful tool for assembly and testing of protein networks important for sperm function.
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Affiliation(s)
- Theodore Chauvin
- School of Molecular Biosciences, Washington State University, Spokane, Washington 99201, USA
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23
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Adastra KL, Frolova AI, Chi MM, Cusumano D, Bade M, Carayannopoulos MO, Moley KH. Slc2a8 deficiency in mice results in reproductive and growth impairments. Biol Reprod 2012; 87:49. [PMID: 22649075 DOI: 10.1095/biolreprod.111.097675] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
SLC2A8, also known as GLUT8, is a facilitative glucose transporter expressed in the testis, brain, liver, heart, uterus, ovary, and fat. In this study we examined the effect of Slc2a8 deficiency on mouse gamete, preimplantation embryo, and implantation phenotype, as well as postnatal growth and physiology. For this model, the transcriptional start site and exons 1-4 were targeted and a lack of protein expression was confirmed by Western immunoblot. Oocytes obtained from Slc2a8(-/-) mice demonstrated abnormal metabolism and ATP production. In addition, deletion of Slc2a8 resulted in impaired decidualization, a critical step in the differentiation of endometrial stromal cells (ESCs), necessary for implantation. This indicates a role for SLC2A8 in decidualization, which is supported by Slc2a8 mRNA expression in both mouse and human ESCs, which increases dramatically in response to hormonal changes occurring during the process of implantation. Ovarian transplantation studies confirm that lack of SLC2A8 affects both the embryo and the implantation processes. This phenotype leads to decreased litter size, and smaller pups at weaning that continue to display an abnormally small growth phenotype into adulthood. The Slc2a8 null mice display decreased body fat by magnetic resonance imaging, and, interestingly, they are resistant to a diet high in fat and carbohydrates.
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Affiliation(s)
- Katie L Adastra
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, Missouri, USA
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24
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Mannowetz N, Wandernoth PM, Wennemuth G. Glucose is a pH-dependent motor for sperm beat frequency during early activation. PLoS One 2012; 7:e41030. [PMID: 22911736 PMCID: PMC3401232 DOI: 10.1371/journal.pone.0041030] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 06/16/2012] [Indexed: 12/17/2022] Open
Abstract
To reach the egg in the ampulla, sperm have to travel along the female genital tract, thereby being dependent on external energy sources and substances to maintain and raise the flagellar beat. The vaginal fluid is rich in lactate, whereas in the uterine fluid glucose is the predominant substrate. This evokes changes in the lactate content of sperm as well as in the intracellular pH (pH(i)) since sperm possess lactate/proton co-transporters. It is well documented that glycolysis yields ATP and that HCO(3)- is a potent factor in the increase of beat frequency. We here show for the first time a pathway that connects both parts. We demonstrate a doubling of beat frequency in the mere presence of glucose. This effect can reversibly be blocked by 2-deoxy-D-glucose, dichloroacetate and aminooxyacetate, strongly suggesting that it requires both glycolysis and mitochondrial oxidation of glycolytic end products. We show that the glucose-mediated acceleration of flagellar beat and ATP production are hastened by a pH(i) ≥7.1, whereas a pH(i) ≤7.1 leaves both parameters unchanged. Since we observed a diminished rise in beat frequency in the presence of specific inhibitors against carbonic anhydrases, soluble adenylyl cyclase and protein kinase, we suggest that the glucose-mediated effect is linked to CO(2) hydration and thus the production of HCO(3)- by intracellular CA isoforms. In summary, we propose that, in sperm, glycolysis is an additional pH(i)-dependent way to produce HCO(3)-, thus enhancing sperm beat frequency and contributing to fertility.
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Affiliation(s)
- Nadja Mannowetz
- Department of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Petra M. Wandernoth
- Department of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Gunther Wennemuth
- Department of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
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25
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Das SK. The facilitative glucose transporter SLC2A8 regulates reproductive outcomes and growth phenotype in mice. Biol Reprod 2012; 87:48. [PMID: 22743299 DOI: 10.1095/biolreprod.112.102988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Affiliation(s)
- Sanjoy K Das
- Division of Reproductive Sciences and Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA.
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26
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Gómez O, Ballester-Lurbe B, Poch E, Mesonero JE, Terrado J. Developmental regulation of glucose transporters GLUT3, GLUT4 and GLUT8 in the mouse cerebellar cortex. J Anat 2010; 217:616-23. [PMID: 20819112 DOI: 10.1111/j.1469-7580.2010.01291.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Glucose uptake into the mammalian nervous system is mediated by the family of facilitative glucose transporter proteins (GLUT). In this work we investigate how the expression of the main neuronal glucose transporters (GLUT3, GLUT4 and GLUT8) is modified during cerebellar cortex maturation. Our results reveal that the levels of the three transporters increase during the postnatal development of the cerebellum. GLUT3 localizes in the growing molecular layer and in the internal granule cell layer. However, the external granule cell layer, Purkinje cell cytoplasm and cytoplasm of the other cerebellar cells lack GLUT3 expression. GLUT4 and GLUT8 have partially overlapping patterns, which are detected in the cytoplasm and dendrites of Purkinje cells, and also in the internal granule cell layer where GLUT8 displays a more diffuse pattern. The differential localization of the transporters suggests that they play different roles in the cerebellum, although GLUT4 and GLUT8 could also perform some compensatory or redundant functions. In addition, the increase in the levels and the area expressing the three transporters suggests that these roles become more important as development advances. Interestingly, the external granule cells, which have been shown to express the monocarboxylate transporter MCT2, express none of the three main neuronal GLUTs. However, when these cells migrate inwardly to differentiate in the internal granule cells, they begin to produce GLUT3, GLUT4 and GLUT8, suggesting that the maturation of the cerebellar granule cells involves a switch in their metabolism in such a way that they start using glucose as they mature.
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Affiliation(s)
- Olga Gómez
- Departamento de Medicina y Cirugía Animal, Universidad CEU-Cardenal Herrera, Moncada, Valencia, Spain
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27
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Augustin R. The protein family of glucose transport facilitators: It's not only about glucose after all. IUBMB Life 2010; 62:315-33. [PMID: 20209635 DOI: 10.1002/iub.315] [Citation(s) in RCA: 167] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The protein family of facilitative glucose transporters comprises 14 isoforms that share common structural features such as 12 transmembrane domains, N- and C-termini facing the cytoplasm of the cell, and a N-glycosylation side either within the first or fifth extracellular loop. Based on their sequence homology, three classes can be distinguished: class I includes GLUT1-4 and GLUT14, class II the "odd transporters" GLUT5, 7, 9, 11, and class III the "even transporters" GLUT6, 8, 10, 12 and the proton driven myoinositol transporter HMIT (or GLUT13). With the cloning and characterization of the more recent class II and III isoforms, it became apparent that despite their structural similarities, the different isoforms not only show a distinct tissue-specific expression pattern but also show distinct characteristics such as alternative splicing, specific (sub)cellular localization, and affinities for a spectrum of substrates. This review summarizes the current understanding of the physiological role for the various transport facilitators based on human genetically inherited disorders or single-nucleotide polymorphisms and knockout mice models. The emphasis of the review will be on the potential functional role of the more recent isoforms.
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Affiliation(s)
- Robert Augustin
- Department of Cardiometabolic Diseases Research, Boehringer-Ingelheim Pharma GmbH&Co KG, Biberach a.d. Riss, Germany.
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28
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Hermo L, Pelletier RM, Cyr DG, Smith CE. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 4: intercellular bridges, mitochondria, nuclear envelope, apoptosis, ubiquitination, membrane/voltage-gated channels, methylation/acetylation, and transcription factors. Microsc Res Tech 2010; 73:364-408. [PMID: 19941288 DOI: 10.1002/jemt.20785] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
As germ cells divide and differentiate from spermatogonia to spermatozoa, they share a number of structural and functional features that are common to all generations of germ cells and these features are discussed herein. Germ cells are linked to one another by large intercellular bridges which serve to move molecules and even large organelles from the cytoplasm of one cell to another. Mitochondria take on different shapes and features and topographical arrangements to accommodate their specific needs during spermatogenesis. The nuclear envelope and pore complex also undergo extensive modifications concomitant with the development of germ cell generations. Apoptosis is an event that is normally triggered by germ cells and involves many proteins. It occurs to limit the germ cell pool and acts as a quality control mechanism. The ubiquitin pathway comprises enzymes that ubiquitinate as well as deubiquitinate target proteins and this pathway is present and functional in germ cells. Germ cells express many proteins involved in water balance and pH control as well as voltage-gated ion channel movement. In the nucleus, proteins undergo epigenetic modifications which include methylation, acetylation, and phosphorylation, with each of these modifications signaling changes in chromatin structure. Germ cells contain specialized transcription complexes that coordinate the differentiation program of spermatogenesis, and there are many male germ cell-specific differences in the components of this machinery. All of the above features of germ cells will be discussed along with the specific proteins/genes and abnormalities to fertility related to each topic.
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Affiliation(s)
- Louis Hermo
- Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, 3640 University Street, Montreal, QC Canada H3A 2B2.
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29
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Hermo L, Pelletier RM, Cyr DG, Smith CE. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 2: changes in spermatid organelles associated with development of spermatozoa. Microsc Res Tech 2010; 73:279-319. [PMID: 19941292 DOI: 10.1002/jemt.20787] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Spermiogenesis is a long process whereby haploid spermatids derived from the meiotic divisions of spermatocytes undergo metamorphosis into spermatozoa. It is subdivided into distinct steps with 19 being identified in rats, 16 in mouse and 8 in humans. Spermiogenesis extends over 22.7 days in rats and 21.6 days in humans. In this part, we review several key events that take place during the development of spermatids from a structural and functional point of view. During early spermiogenesis, the Golgi apparatus forms the acrosome, a lysosome-like membrane bound organelle involved in fertilization. The endoplasmic reticulum undergoes several topographical and structural modifications including the formation of the radial body and annulate lamellae. The chromatoid body is fully developed and undergoes structural and functional modifications at this time. It is suspected to be involved in RNA storing and processing. The shape of the spermatid head undergoes extensive structural changes that are species-specific, and the nuclear chromatin becomes compacted to accommodate the stream-lined appearance of the sperm head. Microtubules become organized to form a curtain or manchette that associates with spermatids at specific steps of their development. It is involved in maintenance of the sperm head shape and trafficking of proteins in the spermatid cytoplasm. During spermiogenesis, many genes/proteins have been implicated in the diverse dynamic events occurring at this time of development of germ cells and the absence of some of these have been shown to result in subfertility or infertility.
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Affiliation(s)
- Louis Hermo
- Faculty of Medicine, Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada H3A 2B2.
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Iyibozkurt AC, Balcik P, Bulgurcuoglu S, Arslan BK, Attar R, Attar E. Effect of vascular endothelial growth factor on sperm motility and survival. Reprod Biomed Online 2009; 19:784-8. [DOI: 10.1016/j.rbmo.2009.09.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Purcell SH, Moley KH. Glucose transporters in gametes and preimplantation embryos. Trends Endocrinol Metab 2009; 20:483-9. [PMID: 19811929 PMCID: PMC6175277 DOI: 10.1016/j.tem.2009.06.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Revised: 06/17/2009] [Accepted: 06/18/2009] [Indexed: 10/20/2022]
Abstract
The oocyte, sperm and preimplantation embryo have unique metabolic needs that must be met to ensure successful pregnancy. The family of facilitative glucose transporters (GLUTs) plays a major role in providing metabolic substrates to these tissues. The variety of GLUTs expressed in these tissues allows for flexibility to adapt to a changing environment. Alterations in glucose transport and metabolism at the earliest stages of development can impact fetal development. Research into the mechanisms of normal glucose transport into cells is critical for improving outcomes in the increasingly common diabetic maternal environment. Here, we review the current understanding in the distribution and role of glucose transporters in gametes and preimplantation embryos under normal and diabetic conditions.
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Affiliation(s)
- Scott H Purcell
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO, USA
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Diril MK, Schmidt S, Krauss M, Gawlik V, Joost HG, Schürmann A, Haucke V, Augustin R. Lysosomal localization of GLUT8 in the testis--the EXXXLL motif of GLUT8 is sufficient for its intracellular sorting via AP1- and AP2-mediated interaction. FEBS J 2009; 276:3729-43. [PMID: 19523115 PMCID: PMC2730553 DOI: 10.1111/j.1742-4658.2009.07089.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 04/25/2009] [Accepted: 05/11/2009] [Indexed: 12/21/2022]
Abstract
The class III sugar transport facilitator GLUT8 co-localizes with the lysosomal protein LAMP1 in heterologous expression systems. GLUT8 carries a [D/E]XXXL[L/I]-type dileucine sorting signal that has been postulated to retain the protein in an endosomal/lysosomal compartment via interactions with clathrin adaptor protein (AP) complexes. However, contradictory findings have been described regarding the subcellular localization of the endogenous GLUT8 and the adaptor proteins that interact with its dileucine motif. Here we demonstrate that endogenous GLUT8 is localized in a late endosomal/lysosomal compartment of spermatocytes and spermatids, and that the adaptor complexes AP1 and AP2, but not AP3 or AP4, interact with its N-terminal intracellular domain (NICD). In addition, fusion of the GLUT8 NICD to the tailless lumenal domain of the IL-2 receptor alpha chain (TAC) protein (interleukin-2 receptor a chain) targeted the protein to intracellular membranes, indicating that its N-terminal dileucine signal is sufficient for endosomal/lysosomal targeting of the transporter. The localization and targeting of GLUT8 show striking similarities to sorting mechanisms reported for lysosomal proteins. Therefore, we suggest a potential role for GLUT8 in the so far unexplored substrate transport across intracellular membranes.
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Affiliation(s)
- Muhammed Kasim Diril
- Institute of Chemistry and Biochemistry, Department of Membrane Biochemistry, Freie Universität & Charité Universitätsmedizin Berlin, Takustrasse 6, Berlin, Germany
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Abstract
GLUT8 is a class III sugar transporter predominantly expressed in testis and brain. In contrast to the class I and class II transporters, hydrophobicity plots predict a short extracellular loop between transmembrane domain (TM)1 and TM2 and a long extracellular loop between TM9 and TM10 that contains the only N-glycosylation site. In vitro translated GLUT8 migrates as a 35-kDa protein that is glycosylated in the presence of microsomal membranes. In heterologous expression systems, glucose transport activity (Km of 2 mM) was inhibited by fructose and galactose. The transporter carries an NH2-terminal endosomal/lysosomal targeting motif ([DE]XXXL[LI]). Accordingly, constitutive GLUT8 has been found to be associated with endosomes and lysosomes but also with membranes of the endoplasmic reticulum. A similar distribution was detected after overexpression of wild-type or tagged GLUT8 in different cell systems. In these cells, none of the conventional signals tested induced a translocation of GLUT8 to the plasma membrane. Therefore, GLUT8 appears to catalyze transport of sugars or sugar derivatives through intracellular membranes. Slc2a8 knockout mice were viable, developed normally, and showed mild alterations in brain (increased proliferation of neuronal cells in dentate gyrus of the hippocampus, hyperactivity), heart (impaired transmission of electrical wave through the atrium), and sperm cells (reduced number of motile sperm cells associated with reduced mitochondrial membrane potential and ATP levels in sperm). The links between molecular function, cellular localization and phenotype of the knockout mouse is unclear and remains to be determined.
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Affiliation(s)
- Stefan Schmidt
- Department of Pharmacology, German Institute of Human Nutrition Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558 Nuthetal, Germany
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Schmidt S, Hommel A, Gawlik V, Augustin R, Junicke N, Florian S, Richter M, Walther DJ, Montag D, Joost HG, Schürmann A. Essential role of glucose transporter GLUT3 for post-implantation embryonic development. J Endocrinol 2009; 200:23-33. [PMID: 18948350 PMCID: PMC2632781 DOI: 10.1677/joe-08-0262] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Deletion of glucose transporter gene Slc2a3 (GLUT3) has previously been reported to result in embryonic lethality. Here, we define the exact time point of growth arrest and subsequent death of the embryo. Slc2a3(-/-) morulae and blastocysts developed normally, implanted in vivo, and formed egg-cylinder-stage embryos that appeared normal until day 6.0. At day 6.5, apoptosis was detected in the ectodermal cells of Slc2a3(-/-) embryos resulting in severe disorganization and growth retardation at day 7.5 and complete loss of embryos at day 12.5. GLUT3 was detected in placental cone, in the visceral ectoderm and in the mesoderm of 7.5-day-old wild-type embryos. Our data indicate that GLUT3 is essential for the development of early post-implanted embryos.
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Affiliation(s)
- S Schmidt
- Department of PharmacologyGerman Institute of Human NutritionPotsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558, NuthetalGermany
| | - A Hommel
- Department of PharmacologyGerman Institute of Human NutritionPotsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558, NuthetalGermany
| | - V Gawlik
- Department of PharmacologyGerman Institute of Human NutritionPotsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558, NuthetalGermany
| | - R Augustin
- Department of PharmacologyGerman Institute of Human NutritionPotsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558, NuthetalGermany
| | - N Junicke
- Department of PharmacologyGerman Institute of Human NutritionPotsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558, NuthetalGermany
| | - S Florian
- Department of ToxicologyGerman Institute of Human NutritionPotsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558, NuthetalGermany
| | - M Richter
- Department of PharmacologyGerman Institute of Human NutritionPotsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558, NuthetalGermany
| | - D J Walther
- Department of Human Molecular GeneticsMax Planck Institute for Molecular GeneticsD-14195, BerlinGermany
| | - D Montag
- Research Group NeurogeneticsLeibniz-Institute for NeurobiologyD-39118, MagdeburgGermany
| | - H-G Joost
- Department of PharmacologyGerman Institute of Human NutritionPotsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558, NuthetalGermany
| | - A Schürmann
- Department of PharmacologyGerman Institute of Human NutritionPotsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558, NuthetalGermany
- Correspondence should be addressed to A Schürmann ()
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Schmidt S, Gawlik V, Hölter SM, Augustin R, Scheepers A, Behrens M, Wurst W, Gailus-Durner V, Fuchs H, Hrabé de Angelis M, Kluge R, Joost HG, Schürmann A. Deletion of glucose transporter GLUT8 in mice increases locomotor activity. Behav Genet 2008; 38:396-406. [PMID: 18461434 PMCID: PMC2480596 DOI: 10.1007/s10519-008-9208-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2007] [Accepted: 04/14/2008] [Indexed: 02/07/2023]
Abstract
Transport of glucose into neuronal cells is predominantly mediated by the glucose transporters GLUT1 and GLUT3. In addition, GLUT8 is expressed in some regions of the brain. By in situ hybridization we detected GLUT8-mRNA in hippocampus, thalamus, and cortex. However, its cellular and physiological function is still unknown. Thus, GLUT8 knockout (Slc2a8−/−) mice were used for a screening approach in the modified hole board (mHB) behavioral test to analyze the role of GLUT8 in the central nervous system. Slc2a8−/− mice showed increased mean velocity, total distance traveled and performed more turns in the mHB test. This hyperactivity of Slc2a8−/− mice was confirmed by monitoring locomotor activity in the home cage and voluntary activity in a running wheel. In addition, Slc2a8−/− mice showed increased arousal as indicated by elevated defecation, reduced latency to the first defecation and a tendency to altered grooming. Furthermore, the mHB test gave evidence that Slc2a8−/− mice exhibit a reduced risk assessment because they performed less rearings in an unprotected area and showed significantly reduced latency to stretched body posture. Our data suggest that behavioral alterations of Slc2a8−/− mice are due to dysfunctions in neuronal processes presumably as a consequence of defects in the glucose metabolism.
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Affiliation(s)
- S Schmidt
- Department of Pharmacology, German Institute of Human Nutrition Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, Nuthetal, Germany
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