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Ting KKY. Fructose-induced metabolic reprogramming of cancer cells. Front Immunol 2024; 15:1375461. [PMID: 38711514 PMCID: PMC11070519 DOI: 10.3389/fimmu.2024.1375461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 04/10/2024] [Indexed: 05/08/2024] Open
Abstract
Excess dietary fructose consumption has been long proposed as a culprit for the world-wide increase of incidence in metabolic disorders and cancer within the past decades. Understanding that cancer cells can gradually accumulate metabolic mutations in the tumor microenvironment, where glucose is often depleted, this raises the possibility that fructose can be utilized by cancer cells as an alternative source of carbon. Indeed, recent research has increasingly identified various mechanisms that show how cancer cells can metabolize fructose to support their proliferating and migrating needs. In light of this growing interest, this review will summarize the recent advances in understanding how fructose can metabolically reprogram different types of cancer cells, as well as how these metabolic adaptations can positively support cancer cells development and malignancy.
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Affiliation(s)
- Kenneth K. Y. Ting
- Department of Immunology, University of Toronto, Toronto, ON, Canada
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
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2
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Ting KKY. Fructose overconsumption-induced reprogramming of microglia metabolism and function. Front Immunol 2024; 15:1375453. [PMID: 38596671 PMCID: PMC11002174 DOI: 10.3389/fimmu.2024.1375453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 03/18/2024] [Indexed: 04/11/2024] Open
Abstract
The overconsumption of dietary fructose has been proposed as a major culprit for the rise of many metabolic diseases in recent years, yet the relationship between a high fructose diet and neurological dysfunction remains to be explored. Although fructose metabolism mainly takes place in the liver and intestine, recent studies have shown that a hyperglycemic condition could induce fructose metabolism in the brain. Notably, microglia, which are tissue-resident macrophages (Mφs) that confer innate immunity in the brain, also express fructose transporters (GLUT5) and are capable of utilizing fructose as a carbon fuel. Together, these studies suggest the possibility that a high fructose diet can regulate the activation and inflammatory response of microglia by metabolic reprogramming, thereby altering the susceptibility of developing neurological dysfunction. In this review, the recent advances in the understanding of microglia metabolism and how it supports its functions will be summarized. The results from both in vivo and in vitro studies that have investigated the mechanistic link between fructose-induced metabolic reprogramming of microglia and its function will then be reviewed. Finally, areas of controversies and their associated implications, as well as directions that warrant future research will be highlighted.
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Affiliation(s)
- Kenneth K. Y. Ting
- Department of Immunology, University of Toronto, Toronto, ON, Canada
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
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Kishida K, Iida T, Yamada T, Toyoda Y. Intestinal absorption of D-fructose isomers, D-allulose, D-sorbose and D-tagatose, via glucose transporter type 5 ( GLUT5) but not sodium-dependent glucose cotransporter 1 (SGLT1) in rats. Br J Nutr 2023; 130:1852-1858. [PMID: 38713062 DOI: 10.1017/s0007114523001113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
D-allulose, D-sorbose and D-tagatose are D-fructose isomers that are called rare sugars. These rare sugars have been studied intensively in terms of biological production and food application as well as physiological effects. There are limited papers with regard to the transporters mediating the intestinal absorption of these rare sugars. We examined whether these rare sugars are absorbed via sodium-dependent glucose cotransporter 1 (SGLT1) as well as via GLUT type 5 (GLUT5) using rats. High-fructose diet fed rats, which express more intestinal GLUT5, exhibited significantly higher peripheral concentrations, Cmax and AUC0–180 min when D-allulose, D-sorbose and D-tagatose were orally administrated. KGA-2727, a selective SGLT1 inhibitor, did not affect the peripheral and portal vein concentrations and pharmacokinetic parameters of these rare sugars. The results suggest that D-allulose, D-sorbose and D-tagatose are likely transported via GLUT5 but not SGLT1 in rat small intestine.
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Affiliation(s)
- Kunihiro Kishida
- Department of Science and Technology on Food Safety, Kindai University, 930 Nishimitani, Kinokawa, Wakayama649-6493, Japan
| | - Tetsuo Iida
- Research and Development, Matsutani Chemical Industry Company, Limited, 5-3 Kita-Itami, Itami, Hyogo664-8508, Japan
| | - Takako Yamada
- Research and Development, Matsutani Chemical Industry Company, Limited, 5-3 Kita-Itami, Itami, Hyogo664-8508, Japan
| | - Yukiyasu Toyoda
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, Aichi468-8503, Japan
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Peschel JM, Reichel LS, Hoffmann T, Enzensperger C, Schubert US, Traeger A, Gottschaldt M. Modification of Branched Poly(ethylene imine) with d-Fructose for Selective Delivery of siRNA into Human Breast Cancer Cells. Macromol Biosci 2023; 23:e2300135. [PMID: 37565461 DOI: 10.1002/mabi.202300135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/31/2023] [Indexed: 08/12/2023]
Abstract
Branched poly(ethylene imine) (bPEI) is frequently used in RNA interference (RNAi) experiments as a cationic polymer for the delivery of small interfering RNA (siRNA) because of its ability to form stable polyplexes that facilitate siRNA uptake. However, the use of bPEI in gene delivery is limited by its cytotoxicity and a need for target specificity. In this work, bPEI is modified with d-fructose to improve biocompatibility and target breast cancer cells through the overexpressed GLUT5 transporter. Fructose-substituted bPEI (Fru-bPEI) is accessible in three steps starting from commercially available protected fructopyranosides and bPEI. Several polymers with varying molecular weights, degrees of substitution, and linker positions on d-fructose (C1 and C3) are synthesized and characterized with NMR spectroscopy, size exclusion chromatography, and elemental analysis. In vitro biological screenings show significantly reduced cytotoxicity of 10 kDa bPEI after fructose functionalization, specific uptake of siRNA polyplexes, and targeted knockdown of green fluorescent protein (GFP) in triple-negative breast cancer cells (MDA-MB-231) compared to noncancer cells (HEK293T).
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Affiliation(s)
- Jan Matthias Peschel
- Institute of Organic and Macromolecular Chemistry, Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Liên Sabrina Reichel
- Institute of Organic and Macromolecular Chemistry, Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Tim Hoffmann
- Institute of Organic and Macromolecular Chemistry, Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | | | - Ulrich Sigmar Schubert
- Institute of Organic and Macromolecular Chemistry, Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Anja Traeger
- Institute of Organic and Macromolecular Chemistry, Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Michael Gottschaldt
- Institute of Organic and Macromolecular Chemistry, Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
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Song A, Mao Y, Wei H. GLUT5: structure, functions, diseases and potential applications. Acta Biochim Biophys Sin (Shanghai) 2023; 55:1519-1538. [PMID: 37674366 PMCID: PMC10582729 DOI: 10.3724/abbs.2023158] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 05/19/2023] [Indexed: 09/08/2023] Open
Abstract
Glucose transporter 5 (GLUT5) is a membrane transporter that specifically transports fructose and plays a key role in dietary fructose uptake and metabolism. In recent years, a high fructose diet has occupied an important position in the daily intake of human beings, resulting in a significant increase in the incidence of obesity and metabolic diseases worldwide. Over the past few decades, GLUT5 has been well understood to play a significant role in the pathogenesis of human digestive diseases. Recently, the role of GLUT5 in human cancer has received widespread attention, and a large number of studies have focused on exploring the effects of changes in GLUT5 expression levels on cancer cell survival, metabolism and metastasis. However, due to various difficulties and shortcomings, the molecular structure and mechanism of GLUT5 have not been fully elucidated, which to some extent prevents us from revealing the relationship between GLUT5 expression and cell carcinogenesis at the protein molecular level. In this review, we summarize the current understanding of the structure and function of mammalian GLUT5 and its relationship to intestinal diseases and cancer and suggest that GLUT5 may be an important target for cancer therapy.
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Affiliation(s)
- Aqian Song
- Department of GastroenterologyBeijing Ditan HospitalCapital Medical UniversityBeijing100015China
| | - Yuanpeng Mao
- Department of GastroenterologyPeking University Ditan Teaching HospitalBeijing100015China
| | - Hongshan Wei
- Department of GastroenterologyBeijing Ditan HospitalCapital Medical UniversityBeijing100015China
- Department of GastroenterologyPeking University Ditan Teaching HospitalBeijing100015China
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Rico A, Valls A, Guembelzu G, Azpitarte M, Aiastui A, Zufiria M, Jaka O, López de Munain A, Sáenz A. Altered expression of proteins involved in metabolism in LGMDR1 muscle is lost in cell culture conditions. Orphanet J Rare Dis 2023; 18:315. [PMID: 37817200 PMCID: PMC10565977 DOI: 10.1186/s13023-023-02873-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 08/24/2023] [Indexed: 10/12/2023] Open
Abstract
BACKGROUND Limb-girdle muscular dystrophy R1 calpain 3-related (LGMDR1) is an autosomal recessive muscular dystrophy due to mutations in the CAPN3 gene. While the pathophysiology of this disease has not been clearly established yet, Wnt and mTOR signaling pathways impairment in LGMDR1 muscles has been reported. RESULTS A reduction in Akt phosphorylation ratio and upregulated expression of proteins implicated in glycolysis (HK-II) and in fructose and lactate transport (GLUT5 and MCT1) in LGMDR1 muscle was observed. In vitro analysis to establish mitochondrial and glycolytic functions of primary cultures were performed, however, no differences between control and patients were observed. Additionally, gene expression analysis showed a lack of correlation between primary myoblasts/myotubes and LGMDR1 muscle while skin fibroblasts and CD56- cells showed a slightly better correlation with muscle. FRZB gene was upregulated in all the analyzed cell types (except in myoblasts). CONCLUSIONS Proteins implicated in metabolism are deregulated in LGMDR1 patients' muscle. Obtained results evidence the limited usefulness of primary myoblasts/myotubes for LGMDR1 gene expression and metabolic studies. However, since FRZB is the only gene that showed upregulation in all the analyzed cell types it is suggested its role as a key regulator of the pathophysiology of the LGMDR1 muscle fiber. The Wnt signaling pathway inactivation, secondary to FRZB upregulation, and GLUT5 overexpression may participate in the impaired adipogenesis in LGMD1R patients.
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Affiliation(s)
- Anabel Rico
- Neurosciences Area, Biodonostia Health Research Institute, San Sebastián, Spain
- CIBERNED, CIBER, Spanish Ministry of Science and Innovation, Carlos III Health Institute, Madrid, Spain
| | - Andrea Valls
- Neurosciences Area, Biodonostia Health Research Institute, San Sebastián, Spain
- CIBERNED, CIBER, Spanish Ministry of Science and Innovation, Carlos III Health Institute, Madrid, Spain
| | - Garazi Guembelzu
- Neurosciences Area, Biodonostia Health Research Institute, San Sebastián, Spain
- CIBERNED, CIBER, Spanish Ministry of Science and Innovation, Carlos III Health Institute, Madrid, Spain
| | - Margarita Azpitarte
- Cell Culture, Histology and Multidisciplinary 3D Printing Platform, Biodonostia Health Research Institute, San Sebastián, Spain
| | - Ana Aiastui
- Department of Neurology, Donostialdea Integrated Health Organization, San Sebastián, Spain
| | - Mónica Zufiria
- Neurosciences Area, Biodonostia Health Research Institute, San Sebastián, Spain
- CIBERNED, CIBER, Spanish Ministry of Science and Innovation, Carlos III Health Institute, Madrid, Spain
| | - Oihane Jaka
- Neurosciences Area, Biodonostia Health Research Institute, San Sebastián, Spain
- CIBERNED, CIBER, Spanish Ministry of Science and Innovation, Carlos III Health Institute, Madrid, Spain
| | - Adolfo López de Munain
- Neurosciences Area, Biodonostia Health Research Institute, San Sebastián, Spain
- CIBERNED, CIBER, Spanish Ministry of Science and Innovation, Carlos III Health Institute, Madrid, Spain
- Department of Neurology, Donostialdea Integrated Health Organization, San Sebastián, Spain
- Department of Neurosciences, University of the Basque Country UPV-EHU, San Sebastián, Spain
- Faculty of Medicine, University of Deusto, Bilbao, Spain
| | - Amets Sáenz
- Neurosciences Area, Biodonostia Health Research Institute, San Sebastián, Spain.
- CIBERNED, CIBER, Spanish Ministry of Science and Innovation, Carlos III Health Institute, Madrid, Spain.
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Yang J, Dong C, Wu J, Liu D, Luo Q, Jin X. Fructose utilization enhanced by GLUT5 promotes lung cancer cell migration via activating glycolysis/AKT pathway. Clin Transl Oncol 2023; 25:1080-1090. [PMID: 36454516 DOI: 10.1007/s12094-022-03015-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 11/12/2022] [Indexed: 12/03/2022]
Abstract
PURPOSE Lung cancer is the leading cause of cancer-related mortalities worldwide, and metastasis contributes to a large number of deaths in lung carcinoma patients. New approaches for anti-metastatic treatment are urgently needed. Enhanced fructose metabolism mediated by GLUT5 directly contributes to cancer metastasis. However, the underlying mechanism remains to be elucidated, which we aimed to explore in this study. METHODS The overexpression and knockdown of SLC2A5, the encoding gene of GLUT5, were established by retrovirus system and CRISPR/Cas9 technology, respectively. Cell migration was conducted by trans-well assay. Western blotting assay was carried out to detect the expression of GLUT5, total AKT, phosphorylated AKT (pAKT-S473 and pAKT-T308) and LDHA. Lactate production was measured by colorimetric assay. Experimental lung metastasis model by tail vein injection was constructed to evaluate the metastatic potential of GLUT5 in vivo. RESULTS Overexpression of SLC2A5 promoted migration of lung cancer cells both in vitro and in vivo, and shortened the overall survival of mice. While, SLC2A5 deletion blocked the migration of lung cancer cells. GLUT5-mediated fructose utilization upregulated phosphorylated AKT, which was responsible for enhanced migration of lung cancer cells. Additionally, GLUT5-mediated fructose utilization boosted glycolysis with overproduction of lactate, resulting in upregulation of phosphorylated AKT. Moreover, lung cancer cell migration and AKT activation were restrained by glycolysis inhibitor 2-deoxy-D-glucose (2-DG) or GLUT5-specific inhibitor 2,5-anhydro-D-mannitol (2,5-AM). CONCLUSION Our study unveils glycolysis/lactate/AKT pathway is responsible for lung cancer cell migration induced by GLUT5-mediated fructose metabolism, providing a potential therapeutic avenue for lung cancer metastasis.
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Affiliation(s)
- Jing Yang
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, 200032, China
- Department of Pharmacy, Shanghai Municipal Hospital of Traditional Chinese Medicine, Shanghai, 200071, China
| | - Changsheng Dong
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, 200032, China
| | - Jia Wu
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, 200032, China
| | - Dan Liu
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, 200032, China
| | - Qin Luo
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, 200032, China.
| | - Xing Jin
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, 200032, China.
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Boyle AJ, Murrell E, Tong J, Schifani C, Narvaez A, Wuest M, West F, Wuest F, Vasdev N. PET Imaging of Fructose Metabolism in a Rodent Model of Neuroinflammation with 6-[ 18F]fluoro-6-deoxy-D-fructose. Molecules 2022; 27:molecules27238529. [PMID: 36500626 PMCID: PMC9736258 DOI: 10.3390/molecules27238529] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022]
Abstract
Fluorine-18 labeled 6-fluoro-6-deoxy-D-fructose (6-[18F]FDF) targets the fructose-preferred facilitative hexose transporter GLUT5, which is expressed predominantly in brain microglia and activated in response to inflammatory stimuli. We hypothesize that 6-[18F]FDF will specifically image microglia following neuroinflammatory insult. 6-[18F]FDF and, for comparison, [18F]FDG were evaluated in unilateral intra-striatal lipopolysaccharide (LPS)-injected male and female rats (50 µg/animal) by longitudinal dynamic PET imaging in vivo. In LPS-injected rats, increased accumulation of 6-[18F]FDF was observed at 48 h post-LPS injection, with plateaued uptake (60-120 min) that was significantly higher in the ipsilateral vs. contralateral striatum (0.985 ± 0.047 and 0.819 ± 0.033 SUV, respectively; p = 0.002, n = 4M/3F). The ipsilateral-contralateral difference in striatal 6-[18F]FDF uptake expressed as binding potential (BPSRTM) peaked at 48 h (0.19 ± 0.11) and was significantly decreased at one and two weeks. In contrast, increased [18F]FDG uptake in the ipsilateral striatum was highest at one week post-LPS injection (BPSRTM = 0.25 ± 0.06, n = 4M). Iba-1 and GFAP immunohistochemistry confirmed LPS-induced activation of microglia and astrocytes, respectively, in ipsilateral striatum. This proof-of-concept study revealed an early response of 6-[18F]FDF to neuroinflammatory stimuli in rat brain. 6-[18F]FDF represents a potential PET radiotracer for imaging microglial GLUT5 density in brain with applications in neuroinflammatory and neurodegenerative diseases.
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Affiliation(s)
- Amanda J. Boyle
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, 250 College St., Toronto, ON M5T 1R8, Canada
- Correspondence: (A.J.B.); (N.V.); Tel.: +1-416-535-8501 (ext. 30884) (A.J.B.); +1-416-535-8501 (ext. 30988) (N.V.)
| | - Emily Murrell
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
| | - Junchao Tong
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
| | - Christin Schifani
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
| | - Andrea Narvaez
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
| | - Melinda Wuest
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2N4, Canada
| | - Frederick West
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2N4, Canada
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada
| | - Frank Wuest
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2N4, Canada
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada
| | - Neil Vasdev
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, 250 College St., Toronto, ON M5T 1R8, Canada
- Correspondence: (A.J.B.); (N.V.); Tel.: +1-416-535-8501 (ext. 30884) (A.J.B.); +1-416-535-8501 (ext. 30988) (N.V.)
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Taneva I, Grumann D, Schmidt D, Taneva E, von Arnim U, Ansorge T, Wex T. Gene variants of the SLC2A5 gene encoding GLUT5, the major fructose transporter, do not contribute to clinical presentation of acquired fructose malabsorption. BMC Gastroenterol 2022; 22:167. [PMID: 35387598 PMCID: PMC8985300 DOI: 10.1186/s12876-022-02244-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 03/25/2022] [Indexed: 11/24/2022] Open
Abstract
Background While role of ALDOB-related gene variants for hereditary fructose intolerance is well established, contribution of gene variants for acquired fructose malabsorption (e.g. SLC2A5, GLUT5) is not well understood. Methods Patients referred to fructose breath test were further selected to identify those having acquired fructose malabsorption. Molecular analysis of genomic DNA included (I) exclusion of 3 main ALDOB gene variants causing hereditary fructose intolerance and (II) sequencing analysis of SLC2A5 gene comprising complete coding region, at least 20 bp of adjacent intronic regions and 700 bp of proximal promoter. Results Among 494 patients, 35 individuals with acquired fructose malabsorption were identified based on pathological fructose-breath test and normal lactose-breath test. Thirty four of them (97%) had negative tissue anti-transglutaminase and/or deamidated gliadin antibodies in their medical records. Molecular analysis of SLC2A5 gene of all 35 subjects identified 5 frequent and 5 singular gene variants mostly in noncoding regions (promoter and intron). Allele frequencies of gene variants were similar to those reported in public databases strongly implying that none of them was associated with acquired fructose malabsorption. Conclusions Gene variants of coding exons, adjacent intronic regions and proximal promoter region of SLC2A5 gene are unlikely to contribute to genetic predisposition of acquired fructose malabsorption.
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Affiliation(s)
- Irina Taneva
- Department of Molecular Genetics, Medical Laboratory for Clinical Chemistry, Microbiology, Infectious Diseases and Genetics "Prof. Schenk/Dr. Ansorge and Colleagues", Schwiesaustr. 11, 39124, Magdeburg, Germany
| | - Dorothee Grumann
- Department of Molecular Genetics, Medical Laboratory for Clinical Chemistry, Microbiology, Infectious Diseases and Genetics "Prof. Schenk/Dr. Ansorge and Colleagues", Schwiesaustr. 11, 39124, Magdeburg, Germany
| | - Dietmar Schmidt
- Medical Office Internal Medicine and Gastroenterology, Olvenstedter Str. 11, 39108, Magdeburg, Germany
| | - Elina Taneva
- Department of Molecular Genetics, Medical Laboratory for Clinical Chemistry, Microbiology, Infectious Diseases and Genetics "Prof. Schenk/Dr. Ansorge and Colleagues", Schwiesaustr. 11, 39124, Magdeburg, Germany
| | - Ulrike von Arnim
- Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-Von-Guericke University, Leipziger Str. 44, 39120, Magdeburg, Germany
| | - Thomas Ansorge
- Department of Molecular Genetics, Medical Laboratory for Clinical Chemistry, Microbiology, Infectious Diseases and Genetics "Prof. Schenk/Dr. Ansorge and Colleagues", Schwiesaustr. 11, 39124, Magdeburg, Germany
| | - Thomas Wex
- Department of Molecular Genetics, Medical Laboratory for Clinical Chemistry, Microbiology, Infectious Diseases and Genetics "Prof. Schenk/Dr. Ansorge and Colleagues", Schwiesaustr. 11, 39124, Magdeburg, Germany. .,Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-Von-Guericke University, Leipziger Str. 44, 39120, Magdeburg, Germany.
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Abstract
Excessive sugar consumption is increasingly considered as a contributor to the emerging epidemics of obesity and the associated cardiometabolic disease. Sugar is added to the diet in the form of sucrose or high-fructose corn syrup, both of which comprise nearly equal amounts of glucose and fructose. The unique aspects of fructose metabolism and properties of fructose-derived metabolites allow for fructose to serve as a physiological signal of normal dietary sugar consumption. However, when fructose is consumed in excess, these unique properties may contribute to the pathogenesis of cardiometabolic disease. Here, we review the biochemistry, genetics, and physiology of fructose metabolism and consider mechanisms by which excessive fructose consumption may contribute to metabolic disease. Lastly, we consider new therapeutic options for the treatment of metabolic disease based upon this knowledge.
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Affiliation(s)
- Mark A Herman
- Division of Endocrinology, Metabolism, and Nutrition, Duke University, Durham, NC, USA; Duke Molecular Physiology Institute, Duke University, Durham, NC, USA; Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA.
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11
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Zakłos-Szyda M, Pietrzyk N, Kowalska-Baron A, Nowak A, Chałaśkiewicz K, Ratajewski M, Budryn G, Koziołkiewicz M. Phenolics-Rich Extracts of Dietary Plants as Regulators of Fructose Uptake in Caco-2 Cells via GLUT5 Involvement. Molecules 2021; 26:4745. [PMID: 34443333 PMCID: PMC8401051 DOI: 10.3390/molecules26164745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/01/2021] [Accepted: 08/03/2021] [Indexed: 12/16/2022] Open
Abstract
The latest data link the chronic consumption of large amounts of fructose present in food with the generation of hypertension and disturbances in carbohydrate and lipid metabolism, which promote the development of obesity, non-alcoholic fatty liver disease, insulin resistance, and type 2 diabetes. This effect is possible after fructose is absorbed by the small intestine cells and, to a lesser extent, by hepatocytes. Fructose transport is dependent on proteins from the family of glucose transporters (GLUTs), among which GLUT5 selectively absorbs fructose from the intestine. In this study, we examined the effect of four phenolic-rich extracts obtained from A. graveolens, B. juncea, and M. chamomilla on fructose uptake by Caco-2 cells. Extracts from B. juncea and M. chamomilla most effectively reduced fluorescent fructose analogue (NBDF) accumulation in Caco-2, as well as downregulated GLUT5 protein levels. These preparations were able to decrease the mRNA level of genes encoding transcription factors regulating GLUT5 expression-thioredoxin-interacting protein (TXNIP) and carbohydrate-responsive element-binding protein (ChREBP). Active extracts contained large amounts of apigenin and flavonols. The molecular docking simulation suggested that some of identified phenolic constituents can play an important role in the inhibition of GLUT5-mediated fructose transport.
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Affiliation(s)
- Małgorzata Zakłos-Szyda
- Faculty of Biotechnology and Food Sciences, Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Łódź, Poland; (N.P.); (K.C.); (M.K.)
| | - Nina Pietrzyk
- Faculty of Biotechnology and Food Sciences, Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Łódź, Poland; (N.P.); (K.C.); (M.K.)
| | - Agnieszka Kowalska-Baron
- Faculty of Biotechnology and Food Sciences, Institute of Natural Products and Cosmetics, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Łódź, Poland;
| | - Adriana Nowak
- Department of Environmental Biotechnology, Lodz University of Technology, Wólczańska 171/173, 90-924 Łódź, Poland;
| | - Katarzyna Chałaśkiewicz
- Faculty of Biotechnology and Food Sciences, Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Łódź, Poland; (N.P.); (K.C.); (M.K.)
| | - Marcin Ratajewski
- Institute of Medical Biology, Laboratory of Epigenetics, Polish Academy of Sciences, Tylna 3a, 90-364 Łódź, Poland;
| | - Grażyna Budryn
- Faculty of Biotechnology and Food Sciences, Institute of Food Technology and Analysis, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Łódź, Poland;
| | - Maria Koziołkiewicz
- Faculty of Biotechnology and Food Sciences, Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Łódź, Poland; (N.P.); (K.C.); (M.K.)
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12
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Basu S, Liu C, Zhou XK, Nishiguchi R, Ha T, Chen J, Johncilla M, Yantiss RK, Montrose DC, Dannenberg AJ. GLUT5 is a determinant of dietary fructose-mediated exacerbation of experimental colitis. Am J Physiol Gastrointest Liver Physiol 2021; 321:G232-G242. [PMID: 34133236 DOI: 10.1152/ajpgi.00059.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The Western diet has been suggested to contribute to the rising incidence of inflammatory bowel diseases. This has led to the hypothesis that fructose, a component of the Western diet, could play a role in the pathogenesis of inflammatory bowel diseases. A high-fructose diet is known to exacerbate experimental colitis. This study tested whether the expression of GLUT5, the fructose transporter, is a determinant of the severity of experimental colitis during elevated fructose consumption and whether ileal inflammation is associated with altered GLUT5 expression in Crohn's disease. Studies in genetically engineered mice showed that in comparison to Glut5+/+ mice, feeding a 15 kcal% fructose diet to Glut5-/- mice led to worse dextran sodium sulfate (DSS)-induced colitis. This effect was associated with elevated levels of colonic fructose and a shift in the fecal microbiota in Glut5-/- mice. Importantly, treatment with broad-spectrum antibiotics protected against the worsening of colitis mediated by dietary fructose in Glut5-/- mice. Gene expression analysis revealed that GLUT5 levels are reduced in the intestines of patients with ileal Crohn's disease. Moreover, levels of GLUT5 negatively correlated with expression of proinflammatory mediators in these samples. Collectively, these results demonstrate that dietary constituent (fructose)-host gene (GLUT5) interactions can shape the colonic microbiota, thereby impacting the severity of colitis.NEW & NOTEWORTHY This study provides the first evidence that reduced levels of GLUT5, the fructose transporter, worsen experimental colitis upon fructose feeding, an effect mediated by changes in the gut microbiota. Moreover, GLUT5 expression is reduced in Crohn's ileitis. Overall, these findings demonstrate the importance of interactions between dietary fructose and host GLUT5 as determinants of both the composition of colonic microbiota and severity of experimental colitis.
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Affiliation(s)
- Srijani Basu
- Department of Medicine, Weill Cornell Medicine, New York, New York
| | - Catherine Liu
- Department of Medicine, Weill Cornell Medicine, New York, New York
| | - Xi Kathy Zhou
- Department of Population Health Sciences, Weill Cornell Medicine, New York, New York
| | | | - Taehoon Ha
- Department of Population Health Sciences, Weill Cornell Medicine, New York, New York
| | - Justin Chen
- Department of Medicine, Weill Cornell Medicine, New York, New York
| | - Melanie Johncilla
- Department of Pathology & Laboratory Medicine, Weill Cornell Medicine, New York, New York
| | - Rhonda K Yantiss
- Department of Pathology & Laboratory Medicine, Weill Cornell Medicine, New York, New York
| | - David C Montrose
- Department of Pathology, Renaissance School of Medicine, Stony Brook University, Stony Brook, New York.,Stony Brook Cancer Center, Stony Brook, New York
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13
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Włodarczyk J, Włodarczyk M, Zielińska M, Jędrzejczak B, Dziki Ł, Fichna J. Blockade of fructose transporter protein GLUT5 inhibits proliferation of colon cancer cells: proof of concept for a new class of anti-tumor therapeutics. Pharmacol Rep 2021; 73:939-45. [PMID: 34052986 DOI: 10.1007/s43440-021-00281-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 04/30/2021] [Accepted: 05/18/2021] [Indexed: 12/14/2022]
Abstract
Background Despite the fact that colorectal cancer (CRC) is one of the most commonly diagnosed cancers in men and women, its current treatment remains unsatisfactory and therefore novel studies proposing new approaches are necessary. A high sugar diet is believed to promote carcinogenesis. Fructose is absorbed from the gastrointestinal tract by members of the glucose transporter family—GLUT. The aim of the study was to characterize the expression of GLUT5 at mRNA level in CRC patients. Moreover, our goal was to elucidate the molecular role of GLUT5 in CRC and assess whether GLUT5 inhibitor may affect the viability of colon cancer cells. Methods The expression of GLUT5 at mRNA level was characterized based on 30 samples from resected colorectal cancers and 30 healthy colonic mucosa specimens from surgical margins. The inhibitory effect of N-[4-(methylsulfonyl)-2-nitrophenyl]-1,3-benzodioxol-5-amine (MSBNA) was assessed on a colon cancer cell line, HT-29, and normal colon epithelium cells—CCD 841 CoN Cells. Results GLUT5 expression was found in 96.7% of cancer specimens and only in 53.3% of healthy mucosa fragments. In cancer tissue, real-time PCR analysis showed almost 2, fivefold (p< 0.001) increase of GLUT5 mRNA expression level compared with the healthy intestinal mucosa. GLUT5 inhibitor, MSNBA (10 µM) significantly decreased the viability of colon cancer cells, while barely affected the viability of normal colon epithelium cells. Conclusions Our study suggests that a strong focus should be put on GLUT5 and its inhibitors for both diagnostic and therapeutic purposes in CRC.
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14
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Nahrjou N, Ghosh A, Tanasova M. Targeting of GLUT5 for Transporter-Mediated Drug-Delivery Is Contingent upon Substrate Hydrophilicity. Int J Mol Sci 2021; 22:ijms22105073. [PMID: 34064801 PMCID: PMC8150966 DOI: 10.3390/ijms22105073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 04/28/2021] [Accepted: 05/08/2021] [Indexed: 12/14/2022] Open
Abstract
Specific link between high fructose uptake and cancer development and progression highlighted fructose transporters as potential means to achieve GLUT-mediated discrimination between normal and cancer cells. The gained expression of fructose-specific transporter GLUT5 in various cancers offers a possibility for developing cancer-specific imaging and bioactive agents. Herein, we explore the feasibility of delivering a bioactive agent through cancer-relevant fructose-specific transporter GLUT5. We employed specific targeting of GLUT5 by 2,5-anhydro-D-mannitol and investigated several drug conjugates for their ability to induce cancer-specific cytotoxicity. The proof-of-concept analysis was carried out for conjugates of chlorambucil (CLB) in GLUT5-positive breast cancer cells and normal breast cells. The cytotoxicity of conjugates was assessed over 24 h and 48 h, and significant dependence between cancer-selectivity and conjugate size was observed. The differences were found to relate to the loss of GLUT5-mediated uptake upon increased conjugate size and hydrophobicity. The findings provide information on the substrate tolerance of GLUT5 and highlight the importance of maintaining appropriate hydrophilicity for GLUT-mediated delivery.
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Affiliation(s)
- Nazanin Nahrjou
- Chemistry Department, Michigan Technological University, Houghton, MI 49931, USA; (N.N.); (A.G.)
| | - Avik Ghosh
- Chemistry Department, Michigan Technological University, Houghton, MI 49931, USA; (N.N.); (A.G.)
| | - Marina Tanasova
- Chemistry Department, Michigan Technological University, Houghton, MI 49931, USA; (N.N.); (A.G.)
- Health Research Institute, Michigan Technological University, Houghton, MI 49931, USA
- Correspondence:
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15
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Spagnuolo MS, Iossa S, Cigliano L. Sweet but Bitter: Focus on Fructose Impact on Brain Function in Rodent Models. Nutrients 2020; 13:E1. [PMID: 33374894 DOI: 10.3390/nu13010001] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/11/2020] [Accepted: 12/17/2020] [Indexed: 12/13/2022] Open
Abstract
Fructose consumption has drastically increased during the last decades due to the extensive commercial use of high-fructose corn syrup as a sweetener for beverages, snacks and baked goods. Fructose overconsumption is known to induce obesity, dyslipidemia, insulin resistance and inflammation, and its metabolism is considered partially responsible for its role in several metabolic diseases. Indeed, the primary metabolites and by-products of gut and hepatic fructolysis may impair the functions of extrahepatic tissues and organs. However, fructose itself causes an adenosine triphosphate (ATP) depletion that triggers inflammation and oxidative stress. Many studies have dealt with the effects of this sugar on various organs, while the impact of fructose on brain function is, to date, less explored, despite the relevance of this issue. Notably, fructose transporters and fructose metabolizing enzymes are present in brain cells. In addition, it has emerged that fructose consumption, even in the short term, can adversely influence brain health by promoting neuroinflammation, brain mitochondrial dysfunction and oxidative stress, as well as insulin resistance. Fructose influence on synaptic plasticity and cognition, with a major impact on critical regions for learning and memory, was also reported. In this review, we discuss emerging data about fructose effects on brain health in rodent models, with special reference to the regulation of food intake, inflammation, mitochondrial function and oxidative stress, insulin signaling and cognitive function.
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16
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Merigo F, Brandolese A, Facchin S, Boschi F, Di Chio M, Savarino E, D'Incà R, Sturniolo GC, Sbarbati A. Immunolocalization of leptin and leptin receptor in colorectal mucosa of ulcerative colitis, Crohn's disease and control subjects with no inflammatory bowel disease. Cell Tissue Res 2020; 383:1103-1122. [PMID: 33159578 PMCID: PMC7960629 DOI: 10.1007/s00441-020-03297-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 09/14/2020] [Indexed: 01/04/2023]
Abstract
The expression of leptin and leptin receptor (Ob-R) has been partially elucidated in colon of patients with inflammatory bowel diseases (IBDs), even though leptin is involved in angiogenesis and inflammation. We previously reported overexpression of GLUT5 fructose transporter, in aberrant clusters of lymphatic vessels in lamina propria of IBD and controls. Here, we examine leptin and Ob-R expression in the same biopsies. Specimens were obtained from patients with ulcerative colitis (UC), Crohn’s disease (CD) and controls who underwent screening for colorectal cancer, follow-up after polypectomy or with a history of lower gastrointestinal symptoms. Immunohistochemistry revealed leptin in apical and basolateral membranes of short epithelial portions, Ob-R on the apical pole of epithelial cells. Leptin and Ob-R were also identified in structures and cells scattered in the lamina propria. In UC, a significant correlation between leptin and Ob-R in the lamina propria was found in all inflamed samples, beyond non-inflamed samples of the proximal tract, while in CD, it was found in inflamed distal samples. Most of the leptin and Ob-R positive areas in the lamina propria were also GLUT5 immunoreactive in inflamed and non-inflamed mucosa. A significant correlation of leptin or Ob-R expression with GLUT5 was observed in the inflamed distal samples from UC. Our findings suggest that there are different sites of leptin and Ob-R expression in large intestine and those in lamina propria do not reflect the status of mucosal inflammation. The co-localization of leptin and/or Ob-R with GLUT5 may indicate concomitance effects in colorectal lamina propria areas.
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Affiliation(s)
- Flavia Merigo
- Department of Neuroscience, Biomedicine and Movement, Human Anatomy and Histology Section, University of Verona, 37134, Verona, Italy.
| | - Alessandro Brandolese
- Department of Medicine, Gastroenterology Section, University of Verona, 37134, Verona, Italy
| | - Sonia Facchin
- Department of Surgery, Oncology and Gastroenterology, Gastroenterology Section, University Hospital of Padua, 35128, Padua, Italy
| | - Federico Boschi
- Department of Computer Science, University of Verona, 37134, Verona, Italy
| | - Marzia Di Chio
- Department of Diagnostic and Public Health, University of Verona, 37134, Verona, Italy
| | - Edoardo Savarino
- Department of Surgery, Oncology and Gastroenterology, Gastroenterology Section, University Hospital of Padua, 35128, Padua, Italy
| | - Renata D'Incà
- Department of Surgery, Oncology and Gastroenterology, Gastroenterology Section, University Hospital of Padua, 35128, Padua, Italy
| | - Giacomo Carlo Sturniolo
- Department of Surgery, Oncology and Gastroenterology, Gastroenterology Section, University Hospital of Padua, 35128, Padua, Italy
| | - Andrea Sbarbati
- Department of Neuroscience, Biomedicine and Movement, Human Anatomy and Histology Section, University of Verona, 37134, Verona, Italy
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17
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Trotta RJ, Ward AK, Swanson KC. Influence of dietary fructose supplementation on visceral organ mass, carbohydrase activity, and mRNA expression of genes involved in small intestinal carbohydrate assimilation in neonatal calves. J Dairy Sci 2020; 103:10060-10073. [PMID: 32921447 DOI: 10.3168/jds.2020-18145] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 06/29/2020] [Indexed: 01/18/2023]
Abstract
The hypothesis of this experiment was that dietary fructose would influence visceral organ mass, carbohydrase activity, and mRNA expression of carbohydrases and nutrient transporters in the small intestine in neonatal calves. Therefore, our objective was to use the neonatal calf as a model to evaluate the effects of postruminal fructose supply on small intestinal carbohydrate assimilation. Ten calves (<7 d of age; 41.2 ± 1.46 kg of body weight) were fed milk replacer at 2.0% of body weight daily (816 ± 90.5 g/d; 272 ± 30.1 g/L; dry-matter basis) in 2 equal portions and assigned to the following dietary treatment groups: (1) milk replacer (control; n = 6) or (2) milk replacer + 2.2 g of fructose/kg of body weight (fructose; n = 4). Calves were fed dietary treatments for 28 d, with jugular blood sampled every 7 d before and after the morning feeding. Calves were slaughtered, and visceral weights were recorded. Postruminal carbohydrase activities were assayed. Quantitative real-time PCR was conducted for small intestinal mRNA expression of nutrient transporters [solute carrier family 2 member 5 (GLUT5), solute carrier family 2 member 2 (GLUT2), and solute carrier family 5 member 1 (SGLT1)], carbohydrases (lactase, maltase-glucoamylase, and sucrase-isomaltase), and ketohexokinase (KHK). Data were analyzed using MIXED procedures in SAS version 9.4 (SAS Institute Inc, Cary, NC). Dietary fructose supplementation decreased serum glucose concentration. Small intestinal mass was greater in calves supplemented with fructose. Dietary fructose supplementation did not influence pancreatic α-amylase, small intestinal isomaltase, or maltase activities. Sucrase activity was undetected in the small intestine. Dietary fructose supplementation increased small intestinal glucoamylase activity per gram of tissue by 30% and increased maltase-glucoamylase mRNA expression by 6.8-fold. Dietary fructose supplementation did not influence mRNA expression of GLUT5, SGLT1, GLUT2, or KHK. Dietary fructose supplementation increased small intestinal lactase mRNA expression by 3.1-fold. Sucrase-isomaltase mRNA expression in the small intestine decreased 5.1-fold with dietary fructose supplementation. Dietary fructose supplementation does not induce sucrase activity in neonatal calves; however, sucrase-isomaltase may be transcriptionally regulated by dietary fructose in neonatal calves. More research is needed to compare glucose and fructose at isocaloric intakes to examine effects of dietary fructose at equal metabolizable energy intake.
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Affiliation(s)
- Ronald J Trotta
- Department of Animal Sciences, North Dakota State University, Fargo 58108
| | - Alison K Ward
- Department of Animal Sciences, North Dakota State University, Fargo 58108
| | - Kendall C Swanson
- Department of Animal Sciences, North Dakota State University, Fargo 58108.
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18
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Abstract
Absorption of monosaccharides is mainly mediated by Na+-D-glucose cotransporter SGLT1 and the facititative transporters GLUT2 and GLUT5. SGLT1 and GLUT2 are relevant for absorption of D-glucose and D-galactose while GLUT5 is relevant for D-fructose absorption. SGLT1 and GLUT5 are constantly localized in the brush border membrane (BBM) of enterocytes, whereas GLUT2 is localized in the basolateral membrane (BLM) or the BBM plus BLM at low and high luminal D-glucose concentrations, respectively. At high luminal D-glucose, the abundance SGLT1 in the BBM is increased. Hence, D-glucose absorption at low luminal glucose is mediated via SGLT1 in the BBM and GLUT2 in the BLM whereas high-capacity D-glucose absorption at high luminal glucose is mediated by SGLT1 plus GLUT2 in the BBM and GLUT2 in the BLM. The review describes functions and regulations of SGLT1, GLUT2, and GLUT5 in the small intestine including diurnal variations and carbohydrate-dependent regulations. Also, the roles of SGLT1 and GLUT2 for secretion of enterohormones are discussed. Furthermore, diseases are described that are caused by malfunctions of small intestinal monosaccharide transporters, such as glucose-galactose malabsorption, Fanconi syndrome, and fructose intolerance. Moreover, it is reported how diabetes, small intestinal inflammation, parental nutrition, bariatric surgery, and metformin treatment affect expression of monosaccharide transporters in the small intestine. Finally, food components that decrease D-glucose absorption and drugs in development that inhibit or downregulate SGLT1 in the small intestine are compiled. Models for regulations and combined functions of glucose transporters, and for interplay between D-fructose transport and metabolism, are discussed.
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Affiliation(s)
- Hermann Koepsell
- Institute for Anatomy and Cell Biology, University of Würzburg, Koellikerstr 6, 97070, Würzburg, Germany.
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19
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Abstract
The SLC2 genes code for a family of GLUT proteins that are part of the major facilitator superfamily (MFS) of membrane transporters. Crystal structures have recently revealed how the unique protein fold of these proteins enables the catalysis of transport. The proteins have 12 transmembrane spans built from a replicated trimer substructure. This enables 4 trimer substructures to move relative to each other, and thereby alternately opening and closing a cleft to either the internal or the external side of the membrane. The physiological substrate for the GLUTs is usually a hexose but substrates for GLUTs can include urate, dehydro-ascorbate and myo-inositol. The GLUT proteins have varied physiological functions that are related to their principal substrates, the cell type in which the GLUTs are expressed and the extent to which the proteins are associated with subcellular compartments. Some of the GLUT proteins translocate between subcellular compartments and this facilitates the control of their function over long- and short-time scales. The control of GLUT function is necessary for a regulated supply of metabolites (mainly glucose) to tissues. Pathophysiological abnormalities in GLUT proteins are responsible for, or associated with, clinical problems including type 2 diabetes and cancer and a range of tissue disorders, related to tissue-specific GLUT protein profiles. The availability of GLUT crystal structures has facilitated the search for inhibitors and substrates and that are specific for each GLUT and that can be used therapeutically. Recent studies are starting to unravel the drug targetable properties of each of the GLUT proteins.
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Affiliation(s)
- Geoffrey D Holman
- Department of Biology and Biochemistry, University of Bath, Bath, BA2 7AY, UK.
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20
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Tilekar K, Upadhyay N, Schweipert M, Hess JD, Macias LH, Mrowka P, Meyer-Almes FJ, Aguilera RJ, Iancu CV, Choe JY, Ramaa CS. Permuted 2,4-thiazolidinedione (TZD) analogs as GLUT inhibitors and their in-vitro evaluation in leukemic cells. Eur J Pharm Sci 2020; 154:105512. [PMID: 32801003 DOI: 10.1016/j.ejps.2020.105512] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/24/2020] [Accepted: 08/10/2020] [Indexed: 01/04/2023]
Abstract
Cancer is a heterogeneous disease, and its treatment requires the identification of new ways to thwart tumor cells. Amongst such emerging targets are glucose transporters (GLUTs, SLC2 family), which are overexpressed by almost all types of cancer cells; their inhibition provides a strategy to disrupt tumor metabolism selectively, leading to antitumor effects. Here, novel thiazolidinedione (TZD) derivatives were designed, synthesized, characterized, and evaluated for their GLUT1, GLUT4, and GLUT5 inhibitory potential, followed by in-vitro cytotoxicity determination in leukemic cell lines. Compounds G5, G16, and G17 inhibited GLUT1, with IC50 values of 5.4 ± 1.3, 26.6 ± 1.8, and 12.6 ± 1.2 μM, respectively. G17 was specific for GLUT1, G16 inhibited GLUT4 (IC50 = 21.6 ± 4.5 μM) comparably but did not affect GLUT5. The most active compound, G5, inhibited all three GLUT types, with GLUT4 IC50 = 9.5 ± 2.8 μM, and GLUT5 IC50 = 34.5 ± 2.4 μM. Docking G5, G16, and G17 to the inward- and outward-facing structural models of GLUT1 predicted ligand binding affinities consistent with the kinetic inhibition data and implicated E380 and W388 of GLUT1 vs. their substitutions in GLUT5 (A388 and A396, respectively) in inhibitor preference for GLUT1. G5 inhibited the proliferation of leukemia CEM cells at low micromolar range (IC50 = 13.4 μM) while being safer for normal blood cells. Investigation of CEM cell cycle progression after treatment with G5 showed that cells accumulated in the G2/M phase. Flow cytometric apoptosis studies revealed that compound G5 induced both early and late-stage apoptosis in CEM cells.
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21
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Tilekar K, Upadhyay N, Hess JD, Macias LH, Mrowka P, Aguilera RJ, Meyer-Almes FJ, Iancu CV, Choe JY, Ramaa CS. Structure guided design and synthesis of furyl thiazolidinedione derivatives as inhibitors of GLUT 1 and GLUT 4, and evaluation of their anti-leukemic potential. Eur J Med Chem 2020; 202:112603. [PMID: 32634629 DOI: 10.1016/j.ejmech.2020.112603] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/14/2020] [Accepted: 06/18/2020] [Indexed: 12/24/2022]
Abstract
Cancer cells increase their glucose uptake and glycolytic activity to meet the high energy requirements of proliferation. Glucose transporters (GLUTs), which facilitate the transport of glucose and related hexoses across the cell membrane, play a vital role in tumor cell survival and are overexpressed in various cancers. GLUT1, the most overexpressed GLUT in many cancers, is emerging as a promising anti-cancer target. To develop GLUT1 inhibitors, we rationally designed, synthesized, structurally characterized, and biologically evaluated in-vitro and in-vivo a novel series of furyl-2-methylene thiazolidinediones (TZDs). Among 25 TZDs tested, F18 and F19 inhibited GLUT1 most potently (IC50 11.4 and 14.7 μM, respectively). F18 was equally selective for GLUT4 (IC50 6.8 μM), while F19 was specific for GLUT1 (IC50 152 μM in GLUT4). In-silico ligand docking studies showed that F18 interacted with conserved residues in GLUT1 and GLUT4, while F19 had slightly different interactions with the transporters. In in-vitro antiproliferative screening of leukemic/lymphoid cells, F18 was most lethal to CEM cells (CC50 of 1.7 μM). Flow cytometry analysis indicated that F18 arrested cell cycle growth in the subG0-G1 phase and lead to cell death due to necrosis and apoptosis. Western blot analysis exhibited alterations in cell signaling proteins, consistent with cell growth arrest and death. In-vivo xenograft study in a CEM model showed that F18 impaired tumor growth significantly.
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Affiliation(s)
- Kalpana Tilekar
- Department of Pharmaceutical Chemistry, Bharati Vidyapeeth's College of Pharmacy, Navi Mumbai, Maharashtra, India
| | - Neha Upadhyay
- Department of Pharmaceutical Chemistry, Bharati Vidyapeeth's College of Pharmacy, Navi Mumbai, Maharashtra, India
| | - Jessica D Hess
- The Cytometry, Screening and Imaging Core Facility & Border Biomedical Research Center & Department of Biological Sciences, The University of Texas at El Paso, El Paso, TX, USA
| | - Lucasantiago Henze Macias
- The Cytometry, Screening and Imaging Core Facility & Border Biomedical Research Center & Department of Biological Sciences, The University of Texas at El Paso, El Paso, TX, USA
| | - Piotr Mrowka
- Department of Biophysics and Human Physiology, Medical University of Warsaw, Chalubinskiego, Warsaw, Poland
| | - Renato J Aguilera
- The Cytometry, Screening and Imaging Core Facility & Border Biomedical Research Center & Department of Biological Sciences, The University of Texas at El Paso, El Paso, TX, USA
| | - Franz-Josef Meyer-Almes
- Department of Chemical Engineering and Biotechnology, University of Applied Sciences, Darmstadt, Germany
| | - Cristina V Iancu
- East Carolina Diabetes and Obesity Institute, Department of Chemistry, East Carolina University, Greenville, NC, USA
| | - Jun-Yong Choe
- East Carolina Diabetes and Obesity Institute, Department of Chemistry, East Carolina University, Greenville, NC, USA; Department of Biochemistry and Molecular Biology, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA.
| | - C S Ramaa
- Department of Pharmaceutical Chemistry, Bharati Vidyapeeth's College of Pharmacy, Navi Mumbai, Maharashtra, India.
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22
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Abstract
Background: Fructose is one of the most common dietary carbohydrates in the whole world, and recent studies have found that fructose consumption is closely related to the oncogenesis and development of tumors, however, very few studies have focused on the fructose in ovarian cancer. GLUT5 (Glucose transporter type 5), as a specific fructose transporter in mammalian cells, has also been found highly expressed in many cancers. Methods: In this study, we investigated the abilities of proliferation, colony formation, and migration of ovarian cancer cells in fructose medium, and then silenced GLUT5 in ovarian cancer cells to explore the role GLUT5 in fructose metabolism in ovarian cancer. Results: The results showed that the ovarian cancer cells had similar abilities of proliferation and migration in fructose medium and glucose medium, but silencing GLUT5 could significantly inhibit these abilities in fructose medium. Meanwhile, we found that GLUT5 was higher expressed in ovarian cancer tissues, and its expression correlated significantly with tumor malignancy and poor survival of ovarian cancer patients. Furthermore, the results of animal experiments also demonstrated that intake too much fructose could prominently increase tumor volume, and silencing GLUT5 could significantly inhibit tumor proliferation. Conclusion: In conclusion, we demonstrate that ovarian cancer cells could utilize fructose for their growth, and restricting the fructose intake or targeting GLUT5 may be efficacious strategies for ovarian cancer therapy.
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Affiliation(s)
- Cuiping Jin
- Department of Gynaecology and Obstetrics, Tianjin Hospital, Tianjin 300211, People's Republic of China
| | - Xiaojin Gong
- Department of Gynaecology and Obstetrics, Tianjin Hospital, Tianjin 300211, People's Republic of China
| | - Yumin Shang
- Department of Gynaecology and Obstetrics, Tianjin Hospital, Tianjin 300211, People's Republic of China
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23
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Jin X, Liang Y, Liu D, Luo Q, Cai L, Wu J, Jia L, Chen WL. An essential role for GLUT5-mediated fructose utilization in exacerbating the malignancy of clear cell renal cell carcinoma. Cell Biol Toxicol 2019; 35:471-83. [PMID: 31102011 DOI: 10.1007/s10565-019-09478-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 05/06/2019] [Indexed: 10/26/2022]
Abstract
Fructose is an important alternative carbon source for several tumors, and GLUT5 is the major fructose transporter which mediates most of fructose uptake in cells. So far, it is unclear whether GLUT5-mediated fructose utilization is important for clear cell renal cell carcinoma (ccRCC). Here, we demonstrated that GLUT5 was highly expressed in a panel of ccRCC cell lines. High GLUT5 expression exacerbated the neoplastic phenotypes of ccRCC cells, including cell proliferation and colony formation. On the other hand, deletion of the GLUT5-encoding gene SLC2A5 dramatically attenuated cellular malignancy via activating the apoptotic pathway. Moreover, administration of 2,5-anhydro-D-mannitol (2,5-AM), a competitive inhibitor of fructose uptake, could markedly suppress ccRCC cell growth. Together, we provide a new mechanistic insight for GLUT5-mediated fructose utilization in ccRCC cells and highlight the therapeutic potential for targeting this metabolic pathway against ccRCC.
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Kishida K, Martinez G, Iida T, Yamada T, Ferraris RP, Toyoda Y. d-Allulose is a substrate of glucose transporter type 5 ( GLUT5) in the small intestine. Food Chem 2018; 277:604-608. [PMID: 30502192 DOI: 10.1016/j.foodchem.2018.11.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 10/23/2018] [Accepted: 11/01/2018] [Indexed: 12/12/2022]
Abstract
d-Allulose has been reported to have beneficial health effects. However, the transport system(s) mediating intestinal d-allulose transport has not yet been clearly identified. The aim of this study was to investigate whether intestinal d-allulose transport is mediated by glucose transporter type 5 (GLUT5). When d-allulose alone was gavaged, plasma d-allulose levels were dramatically higher in rats previously fed fructose. This suggests enhanced intestinal d-allulose absorption paralleled increases in GLUT5 expression observed only in fructose-fed rats. When d-allulose was gavaged with d-fructose, previously observed increases in plasma d-allulose levels were dampened and delayed, indicating d-fructose inhibited transepithelial d-allulose transport into plasma. Tracer D-[14C]-fructose uptake rate was reduced to 54.8% in 50 mM d-allulose and to 16.4% in 50 mM d-fructose, suggesting d-allulose competed with D-[14C]-fructose and the affinity of d-allulose for GLUT5 was lower than that of d-fructose. GLUT5 clearly mediates, likely at lower affinity relative to d-fructose, intestinal d-allulose transport.
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Affiliation(s)
- Kunihiro Kishida
- Department of Science and Technology on Food Safety, Kindai University, 930 Nishimitani, Kinokawa, Wakayama 649-6493, Japan.
| | - Gustavo Martinez
- Department of Pharmacology, Physiology, and Neurosciences, New Jersey Medical School, Rutgers University, 185 S. Orange Avenue, Newark, NJ 07101-1749, USA.
| | - Tetsuo Iida
- Research and Development, Matsutani Chemical Industry Company, Limited, 5-3 Kita-Itami, Itami, Hyogo 664-8508, Japan.
| | - Takako Yamada
- Research and Development, Matsutani Chemical Industry Company, Limited, 5-3 Kita-Itami, Itami, Hyogo 664-8508, Japan.
| | - Ronaldo P Ferraris
- Department of Pharmacology, Physiology, and Neurosciences, New Jersey Medical School, Rutgers University, 185 S. Orange Avenue, Newark, NJ 07101-1749, USA.
| | - Yukiyasu Toyoda
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, Aichi 468-8503, Japan.
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Schreck K, Melzig MF. Intestinal Saturated Long-Chain Fatty Acid, Glucose and Fructose Transporters and Their Inhibition by Natural Plant Extracts in Caco-2 Cells. Molecules 2018; 23:E2544. [PMID: 30301205 DOI: 10.3390/molecules23102544] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 09/29/2018] [Accepted: 10/04/2018] [Indexed: 02/07/2023] Open
Abstract
The intestinal absorption of fatty acids, glucose and fructose is part of the basic requirements for the provision of energy in the body. High access of saturated long-chain fatty acids (LCFA), glucose and fructose can facilitate the development of metabolic diseases, particularly the metabolic syndrome and type-2 diabetes mellitus (T2DM). Research has been done to find substances which decelerate or inhibit intestinal resorption of these specific food components. Promising targets are the inhibition of intestinal long-chain fatty acid (FATP2, FATP4), glucose (SGLT1, GLUT2) and fructose (GLUT2, GLUT5) transporters by plant extracts and by pure substances. The largest part of active components in plant extracts belongs to the group of polyphenols. This review summarizes the knowledge about binding sites of named transporters and lists the plant extracts which were tested in Caco-2 cells regarding uptake inhibition.
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26
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Oh AR, Sohn S, Lee J, Park JM, Nam KT, Hahm KB, Kim YB, Lee HJ, Cha JY. ChREBP deficiency leads to diarrhea-predominant irritable bowel syndrome. Metabolism 2018; 85:286-297. [PMID: 29669261 PMCID: PMC7400734 DOI: 10.1016/j.metabol.2018.04.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 04/04/2018] [Accepted: 04/10/2018] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Fructose malabsorption is a common digestive disorder in which absorption of fructose in the small intestine is impaired. An abnormality of the main intestinal fructose transporter proteins has been proposed as a cause for fructose malabsorption. However the underlying molecular mechanism for this remains unclear. In this study, we investigated whether carbohydrate response element-binding protein (ChREBP) plays a role in intestinal fructose absorption through the regulation of genes involved in fructose transport and metabolism and ion transport. METHODS Wild type (WT) and Chrebp knockout (KO) mice (6 or 8 weeks old) were fed a control diet (55% starch, 15% maltodextrin 10) or high-fructose diet (HFrD, 60% fructose, 10% starch) for 3-12 days. Body weight and food intake were measured, signs of fructose malabsorption were monitored, and the expression of genes involved in fructose transport/metabolism and ion transport was evaluated. Furthermore, transient transfection and chromatin immunoprecipitation were performed to show the direct interaction between ChREBP and carbohydrate response elements in the promoter of Slc2A5, which encodes the fructose transporter GLUT5. RESULTS Chrebp KO mice fed the control diet maintained a constant body weight, whereas those fed a HFrD showed significant weight loss within 3-5 days. In addition, Chrebp KO mice fed the HFrD exhibited a markedly distended cecum and proximal colon containing both fluid and gas, suggesting incomplete fructose absorption. Fructose-induced increases of genes involved in fructose transport (GLUT5), fructose metabolism (fructokinase, aldolase B, triokinase, and lactate dehydrogenase), and gluconeogenesis (glucose-6-phosphatase and fructose-1,6-bisphosphatase) were observed in the intestine of WT but not of Chrebp KO mice. Moreover the Na+/H+ exchanger NHE3, which is involved in Na+ and water absorption in the intestine, was significantly decreased in HFrD-fed Chrebp KO mice. Consistent with this finding, the high-fructose diet-fed Chrebp KO mice developed severe diarrhea. Results of chromatin immunoprecipitation assays showed a direct interaction of ChREBP with the Glut5 promoter, but not the Nhe3 promoter, in the small intestine. Ectopic co-expression of ChREBP and its heterodimer partner Max-like protein X activated the Glut5 promoter in Caco-2BBE cells. CONCLUSIONS ChREBP plays a key role in the dietary fructose transport as well as conversion into lactate and glucose through direct transcriptional control of genes involved in fructose transport, fructolysis, and gluconeogenesis. Moreover, ablation of Chrebp results in a severe diarrhea in mice fed a high-fructose diet, which is associated with the insufficient induction of GLUT5 in the intestine.
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Affiliation(s)
- Ah-Reum Oh
- Department of Biochemistry, Lee Gil Ya Cancer and Diabetes Institute, GAIHST, Gachon University College of Medicine, Incheon 21999, Republic of Korea
| | - Seonyong Sohn
- Department of Biochemistry, Lee Gil Ya Cancer and Diabetes Institute, GAIHST, Gachon University College of Medicine, Incheon 21999, Republic of Korea
| | - Junghoon Lee
- Department of Biochemistry, Lee Gil Ya Cancer and Diabetes Institute, GAIHST, Gachon University College of Medicine, Incheon 21999, Republic of Korea
| | - Jong-Min Park
- CHA Cancer Prevention Research Center, CHA Bio Complex, CHA University, Seongnam 13488, Republic of Korea
| | - Ki Taek Nam
- Severance Biomedical Science Institute, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Ki-Baik Hahm
- CHA Cancer Prevention Research Center, CHA Bio Complex, CHA University, Seongnam 13488, Republic of Korea
| | - Young-Bum Kim
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215, USA
| | - Ho-Jae Lee
- Department of Biochemistry, Lee Gil Ya Cancer and Diabetes Institute, GAIHST, Gachon University College of Medicine, Incheon 21999, Republic of Korea
| | - Ji-Young Cha
- Department of Biochemistry, Lee Gil Ya Cancer and Diabetes Institute, GAIHST, Gachon University College of Medicine, Incheon 21999, Republic of Korea; Gachon Medical Research Institute, Gil Medical Center, Incheon 21565, Republic of Korea.
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27
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Su C, Li H, Gao W. GLUT5 increases fructose utilization and promotes tumor progression in glioma. Biochem Biophys Res Commun 2018; 500:462-469. [PMID: 29660339 DOI: 10.1016/j.bbrc.2018.04.103] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 04/13/2018] [Indexed: 12/20/2022]
Abstract
Fructose is now such an important component of human diets, and several studies have found that some cancer cells could utilize fructose to overcome low glucose micro-environment, but the study on the role of fructose in glioma is rare. To explore the role of fructose in glioma, we detected the proliferation and colony formation ability of glioma cells in fructose medium, and found that the abilities of proliferation and colony formation of glioma cells in fructose medium were similar with abilities in glucose medium, however, fructose just partly restored proliferation ability of normal glial cells. To explore the mechanism, we compared the expression level of GLUT5 (Glucose transporter type 5) in these cell lines, and the results showed that glioma cell lines had higher GLUT5 expression than normal glial cell lines. And knockdown of GLUT5 could significantly inhabit cell proliferation of glioma cells in fructose medium. Furthermore, we found that GLUT5 was also higher expressed in glioma tissues, and GLUT5 expression correlated significantly with glioma malignancy and poor survival of glioma patients (p < 0.01). In addition, we also demonstrated that knockdown of GLUT5 could significantly inhabit tumor proliferation in vivo, and intake fructose could increase tumor volume prominently. Taken together, our data show that fructose can be used by glioma cells, and restrict the fructose intake or targeting GLUT5 could be efficacious strategies in glioma.
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Affiliation(s)
- Chunhai Su
- Department of Neurosurgery, Jining NO.1 People's Hospital, Jining 272011, Shandong, China.
| | - Hui Li
- Department of Nursing, Jining Medical University, Jining 272011, Shandong, China.
| | - Wenbo Gao
- Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou 256600, Shandong, China.
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28
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Kannan S, Begoyan VV, Fedie JR, Xia S, Weseliński ŁJ, Tanasova M, Rao S. Metabolism-Driven High-Throughput Cancer Identification with GLUT5-Specific Molecular Probes. Biosensors (Basel) 2018; 8:bios8020039. [PMID: 29642606 PMCID: PMC6022918 DOI: 10.3390/bios8020039] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 03/19/2018] [Accepted: 04/04/2018] [Indexed: 12/17/2022]
Abstract
Point-of-care applications rely on biomedical sensors to enable rapid detection with high sensitivity and selectivity. Despite advances in sensor development, there are challenges in cancer diagnostics. Detection of biomarkers, cell receptors, circulating tumor cells, gene identification, and fluorescent tagging are time-consuming due to the sample preparation and response time involved. Here, we present a novel approach to target the enhanced metabolism in breast cancers for rapid detection using fluorescent imaging. Fluorescent analogs of fructose target the fructose-specific transporter GLUT5 in breast cancers and have limited to no response from normal cells. These analogs demonstrate a marked difference in adenocarcinoma and premalignant cells leading to a novel detection approach. The vastly different uptake kinetics of the analogs yields two unique signatures for each cell type. We used normal breast cells MCF10A, adenocarcinoma cells MCF7, and premalignant cells MCF10AneoT, with hepatocellular carcinoma cells HepG2 as the negative control. Our data indicated that MCF10AneoT and MCF7 cells had an observable difference in response to only one of the analogs. The response, observed as fluorescence intensity, leads to a two-point assessment of the cells in any sample. Since the treatment time is 10 min, there is potential for use in rapid on-site high-throughput diagnostics.
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Affiliation(s)
- Srinivas Kannan
- Department of Biomedical Engineering, Michigan Technological University, Houghton, MI 49931, USA;
| | - Vagarshak V. Begoyan
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA; (V.V.B.); (J.R.F.); (S.X.); (Ł.J.W.)
| | - Joseph R. Fedie
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA; (V.V.B.); (J.R.F.); (S.X.); (Ł.J.W.)
| | - Shuai Xia
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA; (V.V.B.); (J.R.F.); (S.X.); (Ł.J.W.)
| | - Łukasz J. Weseliński
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA; (V.V.B.); (J.R.F.); (S.X.); (Ł.J.W.)
| | - Marina Tanasova
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA; (V.V.B.); (J.R.F.); (S.X.); (Ł.J.W.)
- Correspondence: (M.T.); (S.R.); Tel.: +1-906-487-1163 (M.T.); +1-906-487-3230 (S.R.)
| | - Smitha Rao
- Department of Biomedical Engineering, Michigan Technological University, Houghton, MI 49931, USA;
- Correspondence: (M.T.); (S.R.); Tel.: +1-906-487-1163 (M.T.); +1-906-487-3230 (S.R.)
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29
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Verdon G, Kang HJ, Drew D. Screening and Scale-Up of GLUT Transporter Constructs Suitable for Biochemical and Structural Studies. Methods Mol Biol 2018; 1713:31-43. [PMID: 29218515 DOI: 10.1007/978-1-4939-7507-5_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Identifying membrane proteins that can be produced and isolated in homogenous form in detergent is a lengthy trial-and-error process that can be facilitated by fluorescence-based screening approaches. We describe (1) the strategy and protocol of cloning by homologous recombination, (2) whole-cell and in-gel fluorescence measurements to estimate GLUT-GFP fusion protein yields, (3) use of size-exclusion chromatography monitored by fluorescence (FSEC) for assessing the homogeneity of the GLUT-GFP fusion proteins, and (4) the protocol for large-scale production and purification of the Bos taurus GLUT5 construct that enabled its crystal structure determination.
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Affiliation(s)
- Grégory Verdon
- Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
- Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, OX11 0FA, UK
| | - Hae Joo Kang
- Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
| | - David Drew
- Department of Biochemistry and Biophysics, Centre for Biomembrane Research, Stockholm University, Stockholm, 106 91, Sweden.
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30
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Ebert K, Ewers M, Bisha I, Sander S, Rasputniac T, Daniel H, Antes I, Witt H. Identification of essential amino acids for glucose transporter 5 ( GLUT5)-mediated fructose transport. J Biol Chem 2017; 293:2115-2124. [PMID: 29259131 DOI: 10.1074/jbc.ra117.001442] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Indexed: 01/27/2023] Open
Abstract
Intestinal fructose uptake is mainly mediated by glucose transporter 5 (GLUT5/SLC2A5). Its closest relative, GLUT7, is also expressed in the intestine but does not transport fructose. For rat Glut5, a change of glutamine to glutamic acid at codon 166 (p.Q166E) has been reported to alter the substrate-binding specificity by shifting Glut5-mediated transport from fructose to glucose. Using chimeric proteins of GLUT5 and GLUT7, here we identified amino acid residues of GLUT5 that define its substrate specificity. The proteins were expressed in NIH-3T3 fibroblasts, and their activities were determined by fructose radiotracer flux. We divided the human GLUT5 sequence into 26 fragments and then replaced each fragment with the corresponding region in GLUT7. All fragments that yielded reduced fructose uptake were analyzed further by assessing the role of individual amino acid residues. Various positions in the first extracellular loop, in the fifth, seventh, eighth, ninth, and tenth transmembrane domains (TMDs), and in the regions between the ninth and tenth TMDs and tenth and 11th TMDs were identified as being important for proper fructose uptake. Although the p.Q167E change did not render the human protein into a glucose transporter, molecular dynamics simulations revealed a drastic change in the dynamics and a movement of the intracellular loop connecting the sixth and seventh TMDs, which covers the exit of the ligand. Finally, we generated a GLUT7-GLUT5 chimera consisting of the N-terminal part of GLUT7 and the C-terminal part of GLUT5. Although this chimera was inactive, we demonstrate fructose transport after introduction of four amino acids derived from GLUT5.
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Affiliation(s)
- Karolin Ebert
- From the Pediatric Nutritional Medicine, Klinikum rechts der Isar (MRI), Else Kröner-Fresenius-Zentrum für Ernährungsmedizin
| | - Maren Ewers
- From the Pediatric Nutritional Medicine, Klinikum rechts der Isar (MRI), Else Kröner-Fresenius-Zentrum für Ernährungsmedizin
| | - Ina Bisha
- Department of Biosciences and Center for Integrated Protein Science Munich, and
| | - Simone Sander
- From the Pediatric Nutritional Medicine, Klinikum rechts der Isar (MRI), Else Kröner-Fresenius-Zentrum für Ernährungsmedizin
| | - Tanja Rasputniac
- From the Pediatric Nutritional Medicine, Klinikum rechts der Isar (MRI), Else Kröner-Fresenius-Zentrum für Ernährungsmedizin
| | - Hannelore Daniel
- Nutritional Physiology, Technische Universität München, 85354 Freising, Germany
| | - Iris Antes
- Department of Biosciences and Center for Integrated Protein Science Munich, and
| | - Heiko Witt
- From the Pediatric Nutritional Medicine, Klinikum rechts der Isar (MRI), Else Kröner-Fresenius-Zentrum für Ernährungsmedizin,
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31
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Fan X, Liu H, Liu M, Wang Y, Qiu L, Cui Y. Increased utilization of fructose has a positive effect on the development of breast cancer. PeerJ 2017; 5:e3804. [PMID: 28970966 PMCID: PMC5622605 DOI: 10.7717/peerj.3804] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 08/23/2017] [Indexed: 01/05/2023] Open
Abstract
Rapid proliferation and Warburg effect make cancer cells consume plenty of glucose, which induces a low glucose micro-environment within the tumor. Up to date, how cancer cells keep proliferating in the condition of glucose insufficiency still remains to be explored. Recent studies have revealed a close correlation between excessive fructose consumption and breast cancer genesis and progression, but there is no convincing evidence showing that fructose could directly promote breast cancer development. Herein, we found that fructose, not amino acids, could functionally replace glucose to support proliferation of breast cancer cells. Fructose endowed breast cancer cells with the colony formation ability and migratory capacity as effective as glucose. Interestingly, although fructose was readily used by breast cancer cells, it failed to restore proliferation of non-tumor cells in the absence of glucose. These results suggest that fructose could be relatively selectively employed by breast cancer cells. Indeed, we observed that a main transporter of fructose, GLUT5, was highly expressed in breast cancer cells and tumor tissues but not in their normal counterparts. Furthermore, we demonstrated that the fructose diet promoted metastasis of 4T1 cells in the mouse models. Taken together, our data show that fructose can be used by breast cancer cells specifically in glucose-deficiency, and suggest that the high-fructose diet could accelerate the progress of breast cancer in vivo.
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Affiliation(s)
- Xiajing Fan
- Laboratory of Cancer Cell Biology, Key Laboratory of Breast Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Hongru Liu
- Laboratory of Cancer Cell Biology, Key Laboratory of Breast Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Miao Liu
- Laboratory of Cancer Cell Biology, Key Laboratory of Breast Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Yuanyuan Wang
- Laboratory of Cancer Cell Biology, Key Laboratory of Breast Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Li Qiu
- Laboratory of Cancer Cell Biology, Key Laboratory of Breast Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Yanfen Cui
- Laboratory of Cancer Cell Biology, Key Laboratory of Breast Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
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32
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Zhou X, Qin X, Gong T, Zhang ZR, Fu Y. d-Fructose Modification Enhanced Internalization of Mixed Micelles in Breast Cancer Cells via GLUT5 Transporters. Macromol Biosci 2017; 17. [PMID: 28346751 DOI: 10.1002/mabi.201600529] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/14/2017] [Indexed: 11/09/2022]
Abstract
d-Fructose modified poly(ε-caprolactone)-polyethylene glycol (PCL-PEG-Fru) diblock amphiphile is synthesized via Cu(I)-catalyzed click chemistry, which self-assembles with D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) into PCL-PEG-Fru/TPGS mixed micelles (PPF MM). It has been proven that glucose transporter (GLUT)5 is overexpressed in MCF-7 cells other than L929 cells. In this study, PPF MM exhibit a significantly higher uptake efficiency than fructose-free PCL-PEG-N3 /TPGS mixed micelles in both 2D MCF-7 cells and 3D tumor spheroids. Also, the presence of free d-fructose competitively inhibits the internalization of PPF MM in MCF-7 cells other than L929 cells. PPF MM show selective tumor accumulation in MCF-7 breast tumor bearing mice xenografts. Taken together, PPF MM represent a promising nanoscale carrier system to achieve GLUT5-mediated cell specific delivery in cancer therapy.
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Affiliation(s)
- Xu Zhou
- Key Laboratory of Drug Targeting and Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China
| | - Xianyan Qin
- Key Laboratory of Drug Targeting and Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China
| | - Tao Gong
- Key Laboratory of Drug Targeting and Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China
| | - Zhi-Rong Zhang
- Key Laboratory of Drug Targeting and Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China
| | - Yao Fu
- Key Laboratory of Drug Targeting and Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China
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33
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Ebert K, Ludwig M, Geillinger KE, Schoberth GC, Essenwanger J, Stolz J, Daniel H, Witt H. Reassessment of GLUT7 and GLUT9 as Putative Fructose and Glucose Transporters. J Membr Biol 2017; 250:171-82. [PMID: 28083649 DOI: 10.1007/s00232-016-9945-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 12/22/2016] [Indexed: 02/01/2023]
Abstract
Although increased dietary fructose consumption is associated with metabolic impairments, the mechanisms and regulation of intestinal fructose absorption are poorly understood. GLUT5 is considered to be the main intestinal fructose transporter. Other GLUT family members, such as GLUT7 and GLUT9 are also expressed in the intestine and were shown to transport fructose and glucose. A conserved isoleucine-containing motif (NXI) was proposed to be essential for fructose transport capacity of GLUT7 and GLUT9 but also of GLUT2 and GLUT5. In assessing whether human GLUT2, GLUT5, GLUT7, and GLUT9 are indeed fructose transporters, we expressed these proteins in Xenopus laevis oocytes. Stably transfected NIH-3T3 fibroblasts were used as second expression system. In proving the role of the NXI motif, variants p.I322V of GLUT2 and p.I296V of GLUT5 were tested as well. Sugar transport was measured by radiotracer flux assays or by metabolomics analysis of cell extracts by GC-MS. Fructose and glucose uptakes by GLUT7 were not increased in both expression systems. In search for the physiological substrate of GLUT7, cells overexpressing the protein were exposed to various metabolite mixtures, but we failed to identify a substrate. Although urate transport by GLUT9 could be shown, neither fructose nor glucose transport was detectable. Fructose uptake was decreased by the GLUT2 p.I322V variant, but remained unaffected in the p.I296V GLUT5 variant. Thus, our work does not find evidence that GLUT7 or GLUT9 transport fructose or glucose or that the isoleucine residue determines fructose specificity. Rather, the physiological substrate of GLUT7 awaits to be discovered.
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34
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Chen WL, Wang YY, Zhao A, Xia L, Xie G, Su M, Zhao L, Liu J, Qu C, Wei R, Rajani C, Ni Y, Cheng Z, Chen Z, Chen SJ, Jia W. Enhanced Fructose Utilization Mediated by SLC2A5 Is a Unique Metabolic Feature of Acute Myeloid Leukemia with Therapeutic Potential. Cancer Cell 2016; 30:779-791. [PMID: 27746145 PMCID: PMC5496656 DOI: 10.1016/j.ccell.2016.09.006] [Citation(s) in RCA: 145] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 04/08/2016] [Accepted: 09/13/2016] [Indexed: 12/28/2022]
Abstract
Rapidly proliferating leukemic progenitor cells consume substantial glucose, which may lead to glucose insufficiency in bone marrow. We show that acute myeloid leukemia (AML) cells are prone to fructose utilization with an upregulated fructose transporter GLUT5, which compensates for glucose deficiency. Notably, AML patients with upregulated transcription of the GLUT5-encoding gene SLC2A5 or increased fructose utilization have poor outcomes. Pharmacological blockage of fructose uptake ameliorates leukemic phenotypes and potentiates the cytotoxicity of the antileukemic agent, Ara-C. In conclusion, this study highlights enhanced fructose utilization as a metabolic feature of AML and a potential therapeutic target.
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Affiliation(s)
- Wen-Lian Chen
- State Key Laboratory of Medical Genomics, Department of Hematology, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Center for Translational Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China; University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Yue-Ying Wang
- State Key Laboratory of Medical Genomics, Department of Hematology, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Aihua Zhao
- Center for Translational Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Li Xia
- State Key Laboratory of Medical Genomics, Department of Hematology, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Guoxiang Xie
- Center for Translational Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China; University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Mingming Su
- Center for Translational Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China; University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Linjing Zhao
- University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Jiajian Liu
- Center for Translational Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Chun Qu
- Center for Translational Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Runmin Wei
- University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Cynthia Rajani
- University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Yan Ni
- Center for Translational Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China; University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Zhen Cheng
- Molecular Imaging Program at Stanford, Department of Radiology and Bio-X Program, Canary Center at Stanford for Cancer Early Detection, School of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Zhu Chen
- State Key Laboratory of Medical Genomics, Department of Hematology, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Sai-Juan Chen
- State Key Laboratory of Medical Genomics, Department of Hematology, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
| | - Wei Jia
- Center for Translational Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China; University of Hawaii Cancer Center, Honolulu, HI 96813, USA.
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Dotimas JR, Lee AW, Schmider AB, Carroll SH, Shah A, Bilen J, Elliott KR, Myers RB, Soberman RJ, Yoshioka J, Lee RT. Diabetes regulates fructose absorption through thioredoxin-interacting protein. eLife 2016; 5. [PMID: 27725089 PMCID: PMC5059142 DOI: 10.7554/elife.18313] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 09/01/2016] [Indexed: 01/17/2023] Open
Abstract
Metabolic studies suggest that the absorptive capacity of the small intestine for fructose is limited, though the molecular mechanisms controlling this process remain unknown. Here we demonstrate that thioredoxin-interacting protein (Txnip), which regulates glucose homeostasis in mammals, binds to fructose transporters and promotes fructose absorption by the small intestine. Deletion of Txnip in mice reduced fructose transport into the peripheral bloodstream and liver, as well as the severity of adverse metabolic outcomes resulting from long-term fructose consumption. We also demonstrate that fructose consumption induces expression of Txnip in the small intestine. Diabetic mice had increased expression of Txnip in the small intestine as well as enhanced fructose uptake and transport into the hepatic portal circulation. The deletion of Txnip in mice abolished the diabetes-induced increase in fructose absorption. Our results indicate that Txnip is a critical regulator of fructose metabolism and suggest that a diabetic state can promote fructose uptake.
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Affiliation(s)
- James R Dotimas
- Department of Stem Cell and Regenerative Biology, Harvard University, Harvard Stem Cell Institute, Cambridge, United States.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, United States
| | - Austin W Lee
- Department of Stem Cell and Regenerative Biology, Harvard University, Harvard Stem Cell Institute, Cambridge, United States.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, United States
| | - Angela B Schmider
- Nephrology Division, Department of Medicine, Massachusetts General Hospital, Charlestown, United States
| | - Shannon H Carroll
- Department of Stem Cell and Regenerative Biology, Harvard University, Harvard Stem Cell Institute, Cambridge, United States.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, United States
| | - Anu Shah
- Department of Stem Cell and Regenerative Biology, Harvard University, Harvard Stem Cell Institute, Cambridge, United States.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, United States
| | - Julide Bilen
- Department of Stem Cell and Regenerative Biology, Harvard University, Harvard Stem Cell Institute, Cambridge, United States.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, United States
| | - Kayla R Elliott
- Department of Stem Cell and Regenerative Biology, Harvard University, Harvard Stem Cell Institute, Cambridge, United States.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, United States
| | - Ronald B Myers
- Department of Stem Cell and Regenerative Biology, Harvard University, Harvard Stem Cell Institute, Cambridge, United States.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, United States
| | - Roy J Soberman
- Nephrology Division, Department of Medicine, Massachusetts General Hospital, Charlestown, United States.,Molecular Imaging Core, Massachusetts General Hospital, Charlestown, United States
| | - Jun Yoshioka
- Department of Stem Cell and Regenerative Biology, Harvard University, Harvard Stem Cell Institute, Cambridge, United States.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, United States
| | - Richard T Lee
- Department of Stem Cell and Regenerative Biology, Harvard University, Harvard Stem Cell Institute, Cambridge, United States.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Cambridge, United States
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36
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Abstract
Too much fructose in the diet can worsen metabolic problems via a process that involves thioredoxin-interacting protein.
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Affiliation(s)
- Anath Shalev
- Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, United States
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37
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Lee Y, Lim Y, Kwon O. Selected Phytochemicals and Culinary Plant Extracts Inhibit Fructose Uptake in Caco-2 Cells. Molecules 2015; 20:17393-404. [PMID: 26393568 PMCID: PMC6331785 DOI: 10.3390/molecules200917393] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 09/01/2015] [Accepted: 09/15/2015] [Indexed: 11/16/2022] Open
Abstract
This study compared the ability of nine culinary plant extracts containing a wide array of phytochemicals to inhibit fructose uptake and then explored the involvement of intestinal fructose transporters and phytochemicals for selected samples. The chemical signature was characterized by high performance liquid chromatography with mass spectrometry. Inhibition of [(14)C]-fructose uptake was tested by using human intestinal Caco-2 cells. Then, the relative contribution of the two apical-facing intestinal fructose transporters, GLUT2 and GLUT5, and the signature components for fructose uptake inhibition was confirmed in naive, phloretin-treated and forskolin-treated Caco-2 cells. HPLC/MS analysis of the chemical signature revealed that guava leaf contained quercetin and catechin, and turmeric contained curcumin, bisdemethoxycurcumin and dimethoxycurcumin. Similar inhibition of fructose uptake (by ~50%) was observed with guava leaf and turmeric in Caco-2 cells, but with a higher contribution of GLUT2 for turmeric and that of GLUT5 for guava leaf. The data suggested that, in turmeric, demethoxycurcumin specifically contributed to GLUT2-mediated fructose uptake inhibition, and curcumin did the same to GLUT5-mediated fructose uptake inhibition, but GLUT2 inhibition was more potent. By contrast, in guava leaf, catechin specifically contributed to GLUT5-mediated fructose uptake inhibition, and quercetin affected both GLUT5- and GLUT2-mediated fructose uptake inhibition, resulting in the higher contribution of GLUT5. These results suggest that demethoxycurcumin is an important contributor to GLUT2-mediated fructose uptake inhibition for turmeric extract, and catechin is the same to GLUT5-mediated fructose uptake inhibition for guava leaf extract. Quercetin, curcumin and bisdemethoxycurcumin contributed to both GLUT5- and GLUT2-mediated fructose uptake inhibition, but the contribution to GLUT5 inhibition was higher than the contribution to GLUT2 inhibition.
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Affiliation(s)
- Yurim Lee
- Department of Nutritional Science and Food Management, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-gu, Seoul 120-750, Korea.
| | - Yeni Lim
- Department of Nutritional Science and Food Management, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-gu, Seoul 120-750, Korea.
| | - Oran Kwon
- Department of Nutritional Science and Food Management, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-gu, Seoul 120-750, Korea.
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38
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Patel C, Douard V, Yu S, Gao N, Ferraris RP. Transport, metabolism, and endosomal trafficking-dependent regulation of intestinal fructose absorption. FASEB J 2015; 29:4046-58. [PMID: 26071406 PMCID: PMC4550372 DOI: 10.1096/fj.15-272195] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 06/02/2015] [Indexed: 01/03/2023]
Abstract
Dietary fructose that is linked to metabolic abnormalities can up-regulate its own absorption, but the underlying regulatory mechanisms are not known. We hypothesized that glucose transporter (GLUT) protein, member 5 (GLUT5) is the primary fructose transporter and that fructose absorption via GLUT5, metabolism via ketohexokinase (KHK), as well as GLUT5 trafficking to the apical membrane via the Ras-related protein-in-brain 11 (Rab11)a-dependent endosomes are each required for regulation. Introducing fructose but not lysine and glucose solutions into the lumen increased by 2- to 10-fold the heterogeneous nuclear RNA, mRNA, protein, and activity levels of GLUT5 in adult wild-type mice consuming chow. Levels of GLUT5 were >100-fold that of candidate apical fructose transporters GLUTs 7, 8, and 12 whose expression, and that of GLUT 2 and the sodium-dependent glucose transporter protein 1 (SGLT1), was not regulated by luminal fructose. GLUT5-knockout (KO) mice exhibited no facilitative fructose transport and no compensatory increases in activity and expression of SGLT1 and other GLUTs. Fructose could not up-regulate GLUT5 in GLUT5-KO, KHK-KO, and intestinal epithelial cell-specific Rab11a-KO mice. The fructose-specific metabolite glyceraldehyde did not increase GLUT5 expression. GLUT5 is the primary transporter responsible for facilitative absorption of fructose, and its regulation specifically requires fructose uptake and metabolism and normal GLUT5 trafficking to the apical membrane.
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Affiliation(s)
- Chirag Patel
- *Department of Pharmacology and Physiology, New Jersey Medical School, and Department of Biological Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
| | - Veronique Douard
- *Department of Pharmacology and Physiology, New Jersey Medical School, and Department of Biological Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
| | - Shiyan Yu
- *Department of Pharmacology and Physiology, New Jersey Medical School, and Department of Biological Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
| | - Nan Gao
- *Department of Pharmacology and Physiology, New Jersey Medical School, and Department of Biological Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
| | - Ronaldo P Ferraris
- *Department of Pharmacology and Physiology, New Jersey Medical School, and Department of Biological Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
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Bouvet V, Jans HS, Wuest M, Soueidan OM, Grant T, Mercer J, McEwan AJB, West FG, Cheeseman CI, Wuest F. Erratum: Automated synthesis and dosimetry of 6-deoxy-6-[(18)F]fluoro-D-fructose (6-[(18)F]FDF): a radiotracer for imaging of GLUT5 in breast cancer. Am J Nucl Med Mol Imaging 2014; 5:95. [PMID: 25625031 PMCID: PMC4299773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 09/26/2014] [Indexed: 06/04/2023]
Abstract
6-Deoxy-6-[(18)F]fluoro-D-fructose (6-[(18)F]FDF) is a promising PET radiotracer for imaging GLUT5 in breast cancer. The present work describes GMP synthesis of 6-[(18)F]FDF in an automated synthesis unit (ASU) and dosimetry calculations to determine radiation doses in humans. GMP synthesis and dosimetry calculations are important prerequisites for first-in-human clinical studies of 6-[(18)F]FDF. The radiochemical synthesis of 6-[(18)F]FDF was optimized and adapted to an automated synthesis process using a Tracerlab FXFN ASU (GE Healthcare). Starting from 30 GBq of cyclotron-produced n.c.a. [(18)F]fluoride, 2.9 ± 0.1 GBq of 6-[(18)F]FDF could be prepared within 50 min including HPLC purification resulting in an overall decay-corrected radiochemical yield of 14 ± 3% (n = 11). Radiochemical purity exceeded 95%, and the specific activity was greater than 5.1 GBq/μmol. Sprague-Dawley rats were used for biodistribution experiments, and dynamic and static small animal PET experiments. Biodistribution studies served as basis for allometric extrapolation to the standard man anatomic model and normal organ-absorbed dose calculations using OLINDA/EXM software. The calculated human effective dose for 6-[(18)F]FDF was 0.0089 mSv/MBq. Highest organ doses with a dose equivalent of 0.0315 mSv/MBq in a humans were found in bone. Injection of 370 MBq (10 mCi) of 6-[(18)F]FDF results in an effective whole body radiation dose of 3.3 mSv in humans, a value comparable to that of other (18)F-labeled PET radiopharmaceuticals. The optimized automated synthesis under GMP conditions, the good radiochemical yield and the favorable human radiation dosimetry estimates support application of 6-[(18)F]FDF in clinical trials for molecular imaging of GLUT5 in breast cancer patients.[This corrects the article on p. 248 in vol. 4.].
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Affiliation(s)
- Vincent Bouvet
- Department of Oncology, University of AlbertaEdmonton, AB - T6G 1Z2, Canada
| | - Hans S Jans
- Department of Oncology, University of AlbertaEdmonton, AB - T6G 1Z2, Canada
| | - Melinda Wuest
- Department of Oncology, University of AlbertaEdmonton, AB - T6G 1Z2, Canada
| | | | - Tina Grant
- Department of Chemistry, University of AlbertaEdmonton, AB - T6G 1Z2, Canada
| | - John Mercer
- Department of Oncology, University of AlbertaEdmonton, AB - T6G 1Z2, Canada
| | | | - Frederick G West
- Department of Chemistry, University of AlbertaEdmonton, AB - T6G 1Z2, Canada
| | - Chris I Cheeseman
- Department of Physiology, University of AlbertaEdmonton, AB - T6G 1Z2, Canada
| | - Frank Wuest
- Department of Oncology, University of AlbertaEdmonton, AB - T6G 1Z2, Canada
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40
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Abstract
The dietary carbohydrate fructose can be incompletely absorbed in the small intestine and is sometimes associated with gastrointestinal symptoms that include motility disturbances and abdominal pain. Fructose malabsorption has been well documented in variable but similar proportions of healthy and populations with functional gastrointestinal disorders. Recent work into the expression of the main intestinal fructose transporter proteins highlight that our understanding of the mechanistic basis for fructose malabsorption and how it differentiates in gastrointestinal patients is incomplete. Until we have further mechanistic insight, restricting dietary fructose intake and other poorly absorbed short-chain carbohydrates and polyols remains an efficacious approach for managing functional gastrointestinal symptoms.
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41
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Wilder-Smith CH, Li X, Ho SS, Leong SM, Wong RK, Koay ES, Ferraris RP. Fructose transporters GLUT5 and GLUT2 expression in adult patients with fructose intolerance. United European Gastroenterol J 2014; 2:14-21. [PMID: 24918004 DOI: 10.1177/2050640613505279] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 08/24/2013] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Gastrointestinal symptoms and malabsorption following fructose ingestion (fructose intolerance) are common in functional gastrointestinal disorders (FGID). The underlying mechanism is unclear, but is hypothesized to be related an abnormality of intestinal fructose transporter proteins. OBJECTIVE To assess the expression of the main intestinal fructose transporter proteins, glucose transport protein 5 (GLUT5) and 2 (GLUT2), in FGID. METHODS The expression of GLUT5 and GLUT2 protein and mRNA in small intestinal biopsy tissue was investigated using real-time reverse-transcription PCR and Western immunoblotting in 11 adults with FGID and fructose intolerance ascertained by breath testing and in 15 controls. RESULTS Median expression levels of GLUT5 mRNA normalized to beta-actin were 0.18 (interquartile range, IQR, 0.13-0.21) in patients and 0.17 (IQR 0.12-0.19) in controls (p > 0.05). Respective levels of GLUT2 mRNA were 0.26 (IQR 0.20-0.31) and 0.26 (IQR 0.19-0.31) (p > 0.05). Median expression levels of GLUT5 protein normalized to alpha-tubulin were 0.95 (IQR 0.52-1.68) in patients and 0.95 (IQR 0.59-1.15) in controls (p > 0.05). Respective protein expression levels for GLUT2 were 1.56 (IQR 1.06-2.14) and 1.35 (IQR 0.96-1.79) (p > 0.05). CONCLUSIONS Human fructose intolerance may not be associated with marked changes in GLUT5 and GLUT2 expression. Replication of these results in a larger subject group, including measures of transporter activation and membrane and subcellular localization, is warranted.
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Affiliation(s)
- Clive H Wilder-Smith
- Brain-Gut Research Group, Bern, Switzerland ; Neurogastroenterology Unit, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore
| | - Xinhua Li
- Neurogastroenterology Unit, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore
| | - Sherry Sy Ho
- Molecular Diagnosis Centre, Department of Laboratory Medicine, National University Hospital, Singapore
| | - Sai Mun Leong
- Neurogastroenterology Unit, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore
| | - Reuben K Wong
- Neurogastroenterology Unit, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore
| | - Evelyn Sc Koay
- Molecular Diagnosis Centre, Department of Laboratory Medicine, National University Hospital, Singapore ; Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore
| | - Ronaldo P Ferraris
- Department of Pharmacology & Physiology, UMDNJ - New Jersey Medical School, Newark, USA
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42
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Honma K, Masuda Y, Mochizuki K, Goda T. Re-feeding rats a high-sucrose diet after 3 days of starvation enhances histone H3 acetylation in transcribed region and expression of jejunal GLUT5 gene. Biosci Biotechnol Biochem 2014; 78:1071-3. [PMID: 25036137 DOI: 10.1080/09168451.2014.912121] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Fasting for 3 days leads to reduction in the expression of GLUT5 and SGLT1 genes in jejunum. Re-feeding a high-sucrose diet in fasted rats enhanced mRNA levels and histone H3 acetylation on transcribed region of GLUT5 gene within 24 h, but not in SGLT1. Responsiveness of jejunal GLUT5 gene is associated with changes in histone H3 acetylation on transcribed region.
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Affiliation(s)
- Kazue Honma
- a Laboratory of Nutritional Physiology , School of Food and Nutritional Sciences, University of Shizuoka , Shizuoka , Japan
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43
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Bouvet V, Jans HS, Wuest M, Soueidan OM, Mercer J, McEwan AJB, West FG, Cheeseman CI, Wuest F. Automated synthesis and dosimetry of 6-deoxy-6-[(18)F]fluoro-D-fructose (6-[(18)F]FDF): a radiotracer for imaging of GLUT5 in breast cancer. Am J Nucl Med Mol Imaging 2014; 4:248-259. [PMID: 24795839 PMCID: PMC3999405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 02/07/2014] [Indexed: 06/03/2023]
Abstract
6-Deoxy-6-[(18)F]fluoro-D-fructose (6-[(18)F]FDF) is a promising PET radiotracer for imaging GLUT5 in breast cancer. The present work describes GMP synthesis of 6-[(18)F]FDF in an automated synthesis unit (ASU) and dosimetry calculations to determine radiation doses in humans. GMP synthesis and dosimetry calculations are important prerequisites for first-in-human clinical studies of 6-[(18)F]FDF. The radiochemical synthesis of 6-[(18)F]FDF was optimized and adapted to an automated synthesis process using a Tracerlab FXFN ASU (GE Healthcare). Starting from 30 GBq of cyclotron-produced n.c.a. [(18)F]fluoride, 2.9 ± 0.1 GBq of 6-[(18)F]FDF could be prepared within 50 min including HPLC purification resulting in an overall decay-corrected radiochemical yield of 14 ± 3% (n = 11). Radiochemical purity exceeded 95%, and the specific activity was greater than 5.1 GBq/μmol. Sprague-Dawley rats were used for biodistribution experiments, and dynamic and static small animal PET experiments. Biodistribution studies served as basis for allometric extrapolation to the standard man anatomic model and normal organ-absorbed dose calculations using OLINDA/EXM software. The calculated human effective dose for 6-[(18)F]FDF was 0.0089 mSv/MBq. Highest organ doses with a dose equivalent of 0.0315 mSv/MBq in a humans were found in bone. Injection of 370 MBq (10 mCi) of 6-[(18)F]FDF results in an effective whole body radiation dose of 3.3 mSv in humans, a value comparable to that of other (18)F-labeled PET radiopharmaceuticals. The optimized automated synthesis under GMP conditions, the good radiochemical yield and the favorable human radiation dosimetry estimates support application of 6-[(18)F]FDF in clinical trials for molecular imaging of GLUT5 in breast cancer patients.
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Affiliation(s)
- Vincent Bouvet
- Department of Oncology, University of AlbertaEdmonton, AB – T6G 1Z2, Canada
| | - Hans S Jans
- Department of Oncology, University of AlbertaEdmonton, AB – T6G 1Z2, Canada
| | - Melinda Wuest
- Department of Oncology, University of AlbertaEdmonton, AB – T6G 1Z2, Canada
| | | | - John Mercer
- Department of Oncology, University of AlbertaEdmonton, AB – T6G 1Z2, Canada
| | | | - Frederick G West
- Department of Chemistry,University of AlbertaEdmonton, AB – T6G 1Z2, Canada
| | - Chris I Cheeseman
- Department of Physiology, University of AlbertaEdmonton, AB – T6G 1Z2, Canada
| | - Frank Wuest
- Department of Oncology, University of AlbertaEdmonton, AB – T6G 1Z2, Canada
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Barrenetxe J, Sánchez O, Barber A, Gascón S, Rodríguez-Yoldi MJ, Lostao MP. TNFα regulates sugar transporters in the human intestinal epithelial cell line Caco-2. Cytokine 2013; 64:181-7. [PMID: 23910014 DOI: 10.1016/j.cyto.2013.07.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 06/10/2013] [Accepted: 07/02/2013] [Indexed: 01/25/2023]
Abstract
PURPOSE During intestinal inflammation TNFα levels are increased and as a consequence malabsorption of nutrients may occur. We have previously demonstrated that TNFα inhibits galactose, fructose and leucine intestinal absorption in animal models. In continuation with our work, the purpose of the present study was to investigate in the human intestinal epithelial cell line Caco-2, the effect of TNFα on sugar transport and to identify the intracellular mechanisms involved. METHODS Caco-2 cells were grown on culture plates and pre-incubated during different periods with various TNFα concentrations before measuring the apical uptake of galactose, α-methyl-glucoside (MG) or fructose for 15 min. To elucidate the signaling pathway implicated, cells were pre-incubated for 30min with the PKA inhibitor H-89 or the PKC inhibitor chelerythrine, before measuring the sugar uptake. The expression in the apical membrane of the transporters implicated in the sugars uptake process (SGLT1 and GLUT5) was determined by Western blot. RESULTS TNFα inhibited 0.1mM MG uptake after pre-incubation of the cells for 6-48h with the cytokine and in the absence of cytokine pre-incubation. In contrast, 5mM fructose uptake was stimulated by TNFα only after long pre-incubation times (24 and 48 h). These effects were mediated by the binding of the cytokine to its specific receptor TNFR1, present in the apical membrane of the Caco-2 cells. Analysis of the expression of the MG and fructose transporters at the brush border membrane of the cells, after 24h pre-incubation with the cytokine, revealed decrease on the amount of SGLT1 and increase on the amount of GLUT5 proteins. Short-term inhibition of MG transport by TNFα was not modified by H-89 but was blocked by chelerythrine. CONCLUSIONS SGLT1 and GLUT5 expression in the plasma membrane is regulated by TNFα in the human epithelial cell line Caco-2 cells, leading to alteration on sugars transport, suggesting that TNFα could be considered as a physiological local regulator of nutrients absorption in response to an intestinal inflammatory status.
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Affiliation(s)
- Jaione Barrenetxe
- Department of Nutrition, Food Science and Physiology, University of Navarra, Pamplona 31008, Spain.
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45
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Abstract
Carbohydrates are an important component of the diet. The carbohydrates that we ingest range from simple monosaccharides (glucose, fructose and galactose) to disaccharides (lactose, sucrose) to complex polysaccharides. Most carbohydrates are digested by salivary and pancreatic amylases, and are further broken down into monosaccharides by enzymes in the brush border membrane (BBM) of enterocytes. For example, lactase-phloridzin hydrolase and sucrase-isomaltase are two disaccharidases involved in the hydrolysis of nutritionally important disaccharides. Once monosaccharides are presented to the BBM, mature enterocytes expressing nutrient transporters transport the sugars into the enterocytes. This paper reviews the early studies that contributed to the development of a working model of intestinal sugar transport, and details the recent advances made in understanding the process by which sugars are absorbed in the intestine.
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Affiliation(s)
- Laurie A Drozdowski
- Division of Gastroenterology, Department of Medicine, University of Alberta, 5150 Dentistry Pharmacy Building, Edmonton, Alberta T6G 2N8, Canada.
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