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Salazar K, Jara N, Ramírez E, de Lima I, Smith-Ghigliotto J, Muñoz V, Ferrada L, Nualart F. Role of vitamin C and SVCT2 in neurogenesis. Front Neurosci 2023; 17:1155758. [PMID: 37424994 PMCID: PMC10324519 DOI: 10.3389/fnins.2023.1155758] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 06/01/2023] [Indexed: 07/11/2023] Open
Abstract
Different studies have established the fundamental role of vitamin C in proliferation, differentiation, and neurogenesis in embryonic and adult brains, as well as in in vitro cell models. To fulfill these functions, the cells of the nervous system regulate the expression and sorting of sodium-dependent vitamin C transporter 2 (SVCT2), as well as the recycling of vitamin C between ascorbic acid (AA) and dehydroascorbic acid (DHA) via a bystander effect. SVCT2 is a transporter preferentially expressed in neurons and in neural precursor cells. In developmental stages, it is concentrated in the apical region of the radial glia, and in adult life, it is expressed preferentially in motor neurons of the cerebral cortex, starting on postnatal day 1. In neurogenic niches, SVCT2 is preferentially expressed in precursors with intermediate proliferation, where a scorbutic condition reduces neuronal differentiation. Vitamin C is a potent epigenetic regulator in stem cells; thus, it can induce the demethylation of DNA and histone H3K27m3 in the promoter region of genes involved in neurogenesis and differentiation, an effect mediated by Tet1 and Jmjd3 demethylases, respectively. In parallel, it has been shown that vitamin C induces the expression of stem cell-specific microRNA, including the Dlk1-Dio3 imprinting region and miR-143, which promotes stem cell self-renewal and suppresses de novo expression of the methyltransferase gene Dnmt3a. The epigenetic action of vitamin C has also been evaluated during gene reprogramming of human fibroblasts to induced pluripotent cells, where it has been shown that vitamin C substantially improves the efficiency and quality of reprogrammed cells. Thus, for a proper effect of vitamin C on neurogenesis and differentiation, its function as an enzymatic cofactor, modulator of gene expression and antioxidant is essential, as is proper recycling from DHA to AA by various supporting cells in the CNS.
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Affiliation(s)
- Katterine Salazar
- Laboratory of Neurobiology and Stem Cells, NeuroCellT, Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
- Center for Advanced Microscopy CMA BIO, University of Concepcion, Concepcion, Chile
| | - Nery Jara
- Department of Pharmacology, University of Concepcion, Concepcion, Chile
| | - Eder Ramírez
- Laboratory of Neurobiology and Stem Cells, NeuroCellT, Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Isabelle de Lima
- Laboratory of Neurobiology and Stem Cells, NeuroCellT, Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Javiera Smith-Ghigliotto
- Laboratory of Neurobiology and Stem Cells, NeuroCellT, Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Valentina Muñoz
- Department of Pharmacology, University of Concepcion, Concepcion, Chile
| | - Luciano Ferrada
- Center for Advanced Microscopy CMA BIO, University of Concepcion, Concepcion, Chile
| | - Francisco Nualart
- Laboratory of Neurobiology and Stem Cells, NeuroCellT, Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
- Center for Advanced Microscopy CMA BIO, University of Concepcion, Concepcion, Chile
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2
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Vitamin C transporter SVCT1 serves a physiological role as a urate importer: functional analyses and in vivo investigations. Pflugers Arch 2023; 475:489-504. [PMID: 36749388 PMCID: PMC10011331 DOI: 10.1007/s00424-023-02792-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 02/08/2023]
Abstract
Uric acid, the end product of purine metabolism in humans, is crucial because of its anti-oxidant activity and a causal relationship with hyperuricemia and gout. Several physiologically important urate transporters regulate this water-soluble metabolite in the human body; however, the existence of latent transporters has been suggested in the literature. We focused on the Escherichia coli urate transporter YgfU, a nucleobase-ascorbate transporter (NAT) family member, to address this issue. Only SLC23A proteins are members of the NAT family in humans. Based on the amino acid sequence similarity to YgfU, we hypothesized that SLC23A1, also known as sodium-dependent vitamin C transporter 1 (SVCT1), might be a urate transporter. First, we identified human SVCT1 and mouse Svct1 as sodium-dependent low-affinity/high-capacity urate transporters using mammalian cell-based transport assays. Next, using the CRISPR-Cas9 system followed by the crossing of mice, we generated Svct1 knockout mice lacking both urate transporter 1 and uricase. In the hyperuricemic mice model, serum urate levels were lower than controls, suggesting that Svct1 disruption could reduce serum urate. Given that Svct1 physiologically functions as a renal vitamin C re-absorber, it could also be involved in urate re-uptake from urine, though additional studies are required to obtain deeper insights into the underlying mechanisms. Our findings regarding the dual-substrate specificity of SVCT1 expand the understanding of urate handling systems and functional evolutionary changes in NAT family proteins.
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3
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Wareing M, Smith CP. Iron Is Filtered by the Kidney and Is Reabsorbed by the Proximal Tubule. Front Physiol 2021; 12:740716. [PMID: 34658926 PMCID: PMC8514780 DOI: 10.3389/fphys.2021.740716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 08/30/2021] [Indexed: 11/20/2022] Open
Abstract
The aim of this study was to determine the iron (Fe) concentration profile within the lumen of the S2 renal proximal convoluted tubule (PCT) and to resolve whether this nephron segment transported Fe. To do this, we performed in vivo renal micropuncture on Wistar rats, collected PCT tubular fluid from superficial nephrons, and measured Fe concentration. The Fe concentration profile along the S2 PCT suggested significant Fe reabsorption. Proximal tubules were also microperfused in vivo with physiological solutions containing Fe and Zn, Cu, Mn, or Cd. PCTs perfused with 12μmol.l−1 55FeCl3 reabsorbed 105.2±12.7 fmol.mm−1.min−1 Fe, 435±52pmol.mm-1.min−1 Na, and 2.7±0.2nl.mm−1.min−1 water (mean ± SEM; n=19). Addition of ascorbate (1mmol.l−1) to the perfusate did not significantly alter Fe, Na, or water reabsorption. Supplementing the control perfusate with 60μmol.l−1 FeSO4 significantly decreased 55Fe uptake. Recalculating for the altered molar activity following addition of unlabeled Fe revealed a three-fold increase in Fe flux. Addition to the perfusate 12μmol.l−1 CuSO4, MnSO4, CdSO4, or ZnSO4 did not affect Fe, Na, or water flux. In conclusion, (1) in vivo, S2 PCTs of rat reabsorb Fe and (2) Fe is reabsorbed along the PCT via a pathway that is insensitive to Cu, Mn, Cd, or Zn. Together, these data demonstrate for the first time the hitherto speculated process of renal Fe filtration and subsequent tubular Fe reabsorption in a living mammal.
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Affiliation(s)
- Mark Wareing
- School of Medical Sciences, The University of Manchester, Manchester, United Kingdom
| | - Craig P Smith
- School of Medical Sciences, The University of Manchester, Manchester, United Kingdom
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4
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Park SS, Ryu YS, Koh DI, Hong SW, Moon JH, Shin JS, Kim MJ, Kim DY, Hong JK, Kim EH, Jeong HR, Park YS, Kim J, Kim DM, Yun H, Shin JY, Jin DH. Mutation SVCT2 promotes cell proliferation, invasion and migration in colorectal cancer. J Cancer 2021; 12:5385-5393. [PMID: 34405001 PMCID: PMC8364649 DOI: 10.7150/jca.57463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 06/04/2021] [Indexed: 12/24/2022] Open
Abstract
The sodium-dependent vitamin C transporter 2 (SVCT2) surface glycoprotein regulates ascorbate accumulation in the plasma, often resulting in the induction of cancer cell death. Therefore, high expression of this gene associates with increased overall survival in several cancers. However, in colorectal cancer (CRC), high (likely mutated) SVCT2 expression relates to poor overall survival, and its functional significance has not been studied. Thus, we hypothesize that mutant SVCT2 expression could affect CRC patient survival. According to biological databases, SVCT2 has been found to be mutated frequently, and SVCT2 E264K has a particularly high pathogenic score (0.98), compared to other SVCT2 mutant sites, in CRC patients. Interestingly, our results reveal expression of SVCT2 E264K in many CRC tissues and cells. Also, we found wild-type SVCT2 expression to be largely localized to the cytoplasm and membrane, while SVCT2 E264K was restricted to the cytoplasm. We further found that SVCT2 E264K overexpression increases cell growth. By contrast, SVCT2 E264K knockdown significantly reduced cell proliferation and promoted cell apoptosis, resulting in inhibition of cell invasion and migration. Taken together, SVCT2 E264K plays a critical role in proliferation in CRC. Our results suggest that SVCT2 E264K could be a promising novel therapeutic target in CRC.
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Affiliation(s)
- Sang-Soo Park
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Yea Seong Ryu
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Dong-In Koh
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea
| | - Seung-Woo Hong
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea
| | - Jai-Hee Moon
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea
| | - Jae-Sik Shin
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea
| | - Mi Jin Kim
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Do Yeon Kim
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jun Ki Hong
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Eun Ho Kim
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Hong-Rae Jeong
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Yoon Sun Park
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Joseph Kim
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Dong Min Kim
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Hyeseon Yun
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Joo-Yeon Shin
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Dong-Hoon Jin
- Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea.,Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
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5
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Le TN, Her J, Sim T, Jung CE, Kang JK, Oh KT. Preparation of Gastro-retentive Tablets Employing Controlled Superporous Networks for Improved Drug Bioavailability. AAPS PharmSciTech 2020; 21:320. [PMID: 33180220 DOI: 10.1208/s12249-020-01851-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 10/12/2020] [Indexed: 12/21/2022] Open
Abstract
The development of an oral formulation that ensures increased bioavailability of drugs is a great challenge for pharmaceutical scientists. Among many oral formulation systems, a drug delivery system employing superporous networks was developed to provide a prolonged gastro-retention time as well as improved bioavailability of drugs with a narrow absorption window in the gastrointestinal tract. Superporous networks (SPNs) were prepared from chitosan by crosslinking with glyoxal and poly(vinyl alcohol) (PVA). The SPNs showed less porosity and decreased water uptake with an increase in the crosslinking density and content of PVA. Gastro-retentive tablets (GRTs) were formulated using hydroxypropyl methylcellulose (HPMC, a hydrophilic polymer) and the prepared SPNs. Ascorbic acid (AA), which is mainly absorbed in the proximal part of the small intestine, was selected as a model drug. The formulated GRTs exhibited no floating lag time and stayed afloat until the end of the dissolution test. The in vitro drug release from the GRTs decreased with a decrease in the water uptake of the SPNs. The profile of drug release from the GRTs corresponded to the first-order and Higuchi drug-release models. Overall, floating tablets composed of the SPNs and HPMC have potential as a favorable platform to ensure sustained release and improved bioavailability of drugs that are absorbed in the proximal part of the small intestine.
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Forman K, Martínez F, Cifuentes M, Fernández M, Bertinat R, Torres P, Salazar K, Godoy A, Nualart F. Dehydroascorbic acid, the oxidized form of vitamin C, improves renal histology and function in old mice. J Cell Physiol 2020; 235:9773-9784. [PMID: 32437012 DOI: 10.1002/jcp.29791] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 04/27/2020] [Accepted: 05/04/2020] [Indexed: 12/18/2022]
Abstract
Oxidative stress and inflammation are crucial factors that increase with age. In the progression of multiple age-related diseases, antioxidants and bioactive compounds have been recognized as useful antiaging agents. Oxidized or reduced vitamin C exerts different actions on tissues and has different metabolism and uptake. In this study, we analyzed the antiaging effect of vitamin C, both oxidized and reduced forms, in renal aging using laser microdissection, quantitative reverse-transcription polymerase chain reaction, and immunohistochemical analyses. In the kidneys of old SAM mice (10 months of age), a model of accelerated senescence, vitamin C, especially in the oxidized form (dehydroascorbic acid [DHA]) improves renal histology and function. Serum creatinine levels and microalbuminuria also decrease after treatment with a decline in azotemia. In addition, sodium-vitamin C cotransporter isoform 1 levels, which were increased during aging, are normalized. In contrast, the pattern of glucose transporter 1 expression is not affected by aging or vitamin C treatment. We conclude that oxidized and reduced vitamin C are potent antiaging therapies and that DHA reverses the kidney damage observed in senescence-accelerated prone mouse 8 to a greater degree.
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Affiliation(s)
- Katherine Forman
- Center for Advanced Microscopy CMA BIO BIO, University of Concepcion, Concepcion, Chile.,Department of Nutrition and Dietetics, Pharmacy School, University of Concepcion, Concepcion, Chile
| | - Fernando Martínez
- Center for Advanced Microscopy CMA BIO BIO, University of Concepcion, Concepcion, Chile.,Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Manuel Cifuentes
- Department of Cell Biology, Genetics and Physiology, University of Malaga, IBIMA, BIONAND, Andalusian Center for Nanomedicine and Biotechnology and Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Malaga, Spain
| | - Marcos Fernández
- Department of Pharmacy, Pharmacy School, University of Concepcion, Concepcion, Chile
| | - Romina Bertinat
- Center for Advanced Microscopy CMA BIO BIO, University of Concepcion, Concepcion, Chile.,Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Pablo Torres
- Department of Pharmacy, Pharmacy School, University of Concepcion, Concepcion, Chile
| | - Katterine Salazar
- Center for Advanced Microscopy CMA BIO BIO, University of Concepcion, Concepcion, Chile.,Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Alejandro Godoy
- Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencias, Universidad San Sebastían, Santiago, Chile.,Department of Urology, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Francisco Nualart
- Center for Advanced Microscopy CMA BIO BIO, University of Concepcion, Concepcion, Chile.,Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
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7
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Gordon DS, Rudinsky AJ, Guillaumin J, Parker VJ, Creighton KJ. Vitamin C in Health and Disease: A Companion Animal Focus. Top Companion Anim Med 2020; 39:100432. [PMID: 32482285 DOI: 10.1016/j.tcam.2020.100432] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 03/13/2020] [Accepted: 03/17/2020] [Indexed: 12/31/2022]
Abstract
Vitamin C is synthesized in the liver in most species, including dogs and cats, and is widely distributed through body tissues. Vitamin C has an important physiologic role in numerous metabolic functions including tissue growth and maintenance, amelioration of oxidative stress, and immune regulation. It is also a co-factor in the production of important substances such as catecholamines and vasopressin. Decreased vitamin C levels have been documented in a wide variety of diseases, and in critically ill human patients may be associated with increased severity of disease and decreased survival. Intravenous supplementation with vitamin C has been proposed as a potential life-saving treatment in conditions such as septic shock, and results of small some human trials are promising. Data in companion in animals is very limited, but the possible benefits and , seemingly low risk of adverse effects , and the low cost of this treatment make vitamin C therapy a promising area of future investigation in critically ill dogs and cats.
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Affiliation(s)
- Daniel S Gordon
- Departments of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus OH, USA
| | - Adam J Rudinsky
- Departments of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus OH, USA
| | - Julien Guillaumin
- Departments of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus OH, USA
| | - Valerie J Parker
- Departments of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus OH, USA
| | - Karina J Creighton
- Departments of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus OH, USA.
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8
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Bartmann L, Schumacher D, von Stillfried S, Sternkopf M, Alampour-Rajabi S, van Zandvoort MAMJ, Kiessling F, Wu Z. Evaluation of Riboflavin Transporters as Targets for Drug Delivery and Theranostics. Front Pharmacol 2019; 10:79. [PMID: 30787877 PMCID: PMC6372557 DOI: 10.3389/fphar.2019.00079] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 01/21/2019] [Indexed: 12/30/2022] Open
Abstract
The retention and cellular internalization of drug delivery systems and theranostics for cancer therapy can be improved by targeting molecules. Since an increased uptake of riboflavin was reported for various cancers, riboflavin and its derivatives may be promising binding moieties to trigger internalization via the riboflavin transporters (RFVT) 1, 2, and 3. Riboflavin is a vitamin with pivotal role in energy metabolism and indispensable for cellular growth. In previous preclinical studies on mice, we showed the target-specific accumulation of riboflavin-functionalized nanocarriers in cancer cells. Although the uptake mechanism of riboflavin has been studied for over a decade, little is known about the riboflavin transporters and their expression on cancer cells, tumor stroma, and healthy tissues. Furthermore, evidence is lacking concerning the representativeness of the preclinical findings to the situation in humans. In this study, we investigated the expression pattern of riboflavin transporters in human squamous cell carcinoma (SCC), melanoma and luminal A breast cancer samples, as well as in healthy skin, breast, aorta, and kidney tissues. Low constitutive expression levels of RFVT1-3 were found on all healthy tissues, while RFVT2 and 3 were significantly overexpressed in melanoma, RFVT1 and 3 in luminal A breast cancer and RFVT1-3 in SCC. Correspondingly, the SCC cell line A431 was highly positive for all RFVTs, thus qualifying as suitable in vitro model. In contrast, activated endothelial cells (HUVEC) only presented with a strong expression of RFVT2, and HK2 kidney cells only with a low constitutive expression of RFVT1-3. Functional in vitro studies on A431 and HK2 cells using confocal microscopy showed that riboflavin uptake is mostly ATP dependent and primarily driven by endocytosis. Furthermore, riboflavin is partially trafficked to the mitochondria. Riboflavin uptake and trafficking was significantly higher in A431 than in healthy kidney cells. Thus, this manuscript supports the hypothesis that addressing the riboflavin internalization pathway may be highly valuable for tumor targeted drug delivery.
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Affiliation(s)
- Lisa Bartmann
- Institute for Experimental Molecular Imaging, University Clinic, RWTH Aachen University, Aachen, Germany.,Institute for Molecular Cardiovascular Research, University Clinic, RWTH Aachen University, Aachen, Germany
| | - David Schumacher
- Institute for Molecular Cardiovascular Research, University Clinic, RWTH Aachen University, Aachen, Germany
| | | | - Marieke Sternkopf
- Institute for Molecular Cardiovascular Research, University Clinic, RWTH Aachen University, Aachen, Germany
| | - Setareh Alampour-Rajabi
- Institute for Molecular Cardiovascular Research, University Clinic, RWTH Aachen University, Aachen, Germany
| | - Marc A M J van Zandvoort
- Institute for Molecular Cardiovascular Research, University Clinic, RWTH Aachen University, Aachen, Germany.,Department of Genetics and Molecular Cell Biology, School for Cardiovascular Diseases (CARIM), School for Oncology and Developmental Biology (GROW), Maastricht University, Maastricht, Netherlands
| | - Fabian Kiessling
- Institute for Experimental Molecular Imaging, University Clinic, RWTH Aachen University, Aachen, Germany
| | - Zhuojun Wu
- Institute for Experimental Molecular Imaging, University Clinic, RWTH Aachen University, Aachen, Germany.,Institute for Molecular Cardiovascular Research, University Clinic, RWTH Aachen University, Aachen, Germany
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9
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Subramanian VS, Sabui S, Moradi H, Marchant JS, Said HM. Inhibition of intestinal ascorbic acid uptake by lipopolysaccharide is mediated via transcriptional mechanisms. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:556-565. [PMID: 29030247 DOI: 10.1016/j.bbamem.2017.10.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 09/14/2017] [Accepted: 10/08/2017] [Indexed: 12/28/2022]
Abstract
Ascorbic acid (AA) accumulation in intestinal epithelial cells is an active transport process mainly mediated by two sodium-dependent vitamin C transporters (SVCT-1 and SVCT-2). To date, little is known about the effect of gut microbiota generated lipopolysaccharide (LPS) on intestinal absorption of water-soluble vitamins. Therefore, the objective of this study was to investigate the effects of bacterially-derived LPS on AA homeostasis in enterocytes using Caco-2 cells, mouse intestine and intestinal enteroids models. Pre-treating Caco-2 cells and mice with LPS led to a significant decrease in carrier-mediated AA uptake. This inhibition was associated with a significant reduction in SVCT-1 and SVCT-2 protein, mRNA, and hnRNA expression. Furthermore, pre-treating enteroids with LPS also led to a marked decrease in SVCT-1 and SVCT-2 protein and mRNA expression. Inhibition of SVCT-1 and SVCT-2 occurred at least in part at the transcriptional level as promoter activity of SLC23A1 and SLC23A2 was attenuated following LPS treatment. Subsequently, we examined the protein and mRNA expression levels of HNF1α and Sp1 transcription factors, which are needed for basal SLC23A1 and SLC23A2 promoter activity, and found that they were significantly decreased in the LPS treated Caco-2 cells and mouse jejunum; this was reflected on level of the observed reduction in the interaction of these transcription factors with their respective promoters in Caco-2 cells treated with LPS. Our findings indicate that LPS inhibits intestinal carrier- mediated AA uptake by down regulating the expression of both vitamin C transporters and transcriptional regulation of SLC23A1 and SLC23A2 genes.
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Affiliation(s)
- Veedamali S Subramanian
- Departments of Medicine, Physiology and Biophysics, University of California, Irvine, CA 92697, United States; Department of Veterans Affairs Medical Center, Long Beach, CA 90822, United States.
| | - Subrata Sabui
- Departments of Medicine, Physiology and Biophysics, University of California, Irvine, CA 92697, United States; Department of Veterans Affairs Medical Center, Long Beach, CA 90822, United States
| | - Hamid Moradi
- Departments of Medicine, Physiology and Biophysics, University of California, Irvine, CA 92697, United States; Department of Veterans Affairs Medical Center, Long Beach, CA 90822, United States
| | - Jonathan S Marchant
- Department of Pharmacology, University of Minnesota Medical School, MN 55455, United States
| | - Hamid M Said
- Departments of Medicine, Physiology and Biophysics, University of California, Irvine, CA 92697, United States; Department of Veterans Affairs Medical Center, Long Beach, CA 90822, United States
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10
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Forman K, Martínez F, Cifuentes M, Bertinat R, Salazar K, Nualart F. Aging Selectively Modulates Vitamin C Transporter Expression Patterns in the Kidney. J Cell Physiol 2017; 232:2418-2426. [DOI: 10.1002/jcp.25504] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Accepted: 07/26/2016] [Indexed: 12/18/2022]
Affiliation(s)
- Katherine Forman
- Centro de Microscopía Avanzada, CMA BIO BIO; Facultad de Ciencias Biológicas, Universidad de Concepción; Concepción Chile
- Departamento de Nutrición y Dietética, Facultad de Farmacia; Universidad de Concepción; Concepción Chile
| | - Fernando Martínez
- Centro de Microscopía Avanzada, CMA BIO BIO; Facultad de Ciencias Biológicas, Universidad de Concepción; Concepción Chile
| | - Manuel Cifuentes
- Departamento de Biología Celular, Génetica y Fisiología, Laboratorio de Fisiología Animal; Facultad de Ciencias, Centro de Investigaciones Biomédicas en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Universidad de Málaga; Málaga España
| | - Romina Bertinat
- Centro de Microscopía Avanzada, CMA BIO BIO; Facultad de Ciencias Biológicas, Universidad de Concepción; Concepción Chile
| | - Katterine Salazar
- Centro de Microscopía Avanzada, CMA BIO BIO; Facultad de Ciencias Biológicas, Universidad de Concepción; Concepción Chile
| | - Francisco Nualart
- Centro de Microscopía Avanzada, CMA BIO BIO; Facultad de Ciencias Biológicas, Universidad de Concepción; Concepción Chile
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11
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SVCT2 Overexpression in Neuroblastoma Cells Induces Cellular Branching that is Associated with ERK Signaling. Mol Neurobiol 2015; 53:6668-6679. [DOI: 10.1007/s12035-015-9553-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Accepted: 11/18/2015] [Indexed: 12/21/2022]
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12
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Nualart F, Mack L, García A, Cisternas P, Bongarzone ER, Heitzer M, Jara N, Martínez F, Ferrada L, Espinoza F, Baeza V, Salazar K. Vitamin C Transporters, Recycling and the Bystander Effect in the Nervous System: SVCT2 versus Gluts. ACTA ACUST UNITED AC 2014; 4:209. [PMID: 25110615 PMCID: PMC4126260 DOI: 10.4172/2157-7633.1000209] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Vitamin C is an essential micronutrient in the human diet; its deficiency leads to a number of symptoms and ultimately death. After entry into cells within the central nervous system (CNS) through sodium vitamin C transporters (SVCTs) and facilitative glucose transporters (GLUTs), vitamin C functions as a neuromodulator, enzymatic cofactor, and reactive oxygen species (ROS) scavenger; it also stimulates differentiation. In this review, we will compare the molecular and structural aspects of vitamin C and glucose transporters and their expression in endothelial or choroid plexus cells, which form part of the blood-brain barrier and blood-cerebrospinal fluid (CSF) barrier, respectively. Additionally, we will describe SVCT and GLUT expression in different cells of the brain as well as SVCT2 distribution in tanycytes and astrocytes of the hypothalamic region. Finally, we will describe vitamin C recycling in the brain, which is mediated by a metabolic interaction between astrocytes and neurons, and the role of the "bystander effect" in the recycling mechanism of vitamin C in both normal and pathological conditions.
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Affiliation(s)
- Francisco Nualart
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Lauren Mack
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Andrea García
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Pedro Cisternas
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Ernesto R Bongarzone
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois Chicago, USA
| | - Marjet Heitzer
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Nery Jara
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Fernando Martínez
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Luciano Ferrada
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Francisca Espinoza
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Victor Baeza
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
| | - Katterine Salazar
- Center for Advanced Microscopy CMA BIO-BIO, Neurobiology and Stem cell Laboratory, Concepcion University, Chile
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13
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Lindblad M, Tveden-Nyborg P, Lykkesfeldt J. Regulation of vitamin C homeostasis during deficiency. Nutrients 2013; 5:2860-79. [PMID: 23892714 PMCID: PMC3775232 DOI: 10.3390/nu5082860] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 07/15/2013] [Accepted: 07/18/2013] [Indexed: 12/31/2022] Open
Abstract
Large cross-sectional population studies confirm that vitamin C deficiency is common in humans, affecting 5%–10% of adults in the industrialized world. Moreover, significant associations between poor vitamin C status and increased morbidity and mortality have consistently been observed. However, the absorption, distribution and elimination kinetics of vitamin C in vivo are highly complex, due to dose-dependent non-linearity, and the specific regulatory mechanisms are not fully understood. Particularly, little is known about how adaptive mechanisms during states of deficiency affect the overall regulation of vitamin C transport in the body. This review discusses mechanisms of vitamin C transport and potential means of regulation with special emphasis on capacity and functional properties, such as differences in the Km of vitamin C transporters in different target tissues, in some instances demonstrating a tissue-specific distribution.
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Affiliation(s)
- Maiken Lindblad
- Section of Experimental Animal Models, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Ridebanevej 9, Frederiksberg C 1870, Denmark.
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14
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Ulloa V, García-Robles M, Martínez F, Salazar K, Reinicke K, Pérez F, Godoy DF, Godoy AS, Nualart F. Human choroid plexus papilloma cells efficiently transport glucose and vitamin C. J Neurochem 2013; 127:403-14. [DOI: 10.1111/jnc.12295] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 04/18/2013] [Accepted: 04/19/2013] [Indexed: 01/20/2023]
Affiliation(s)
- Viviana Ulloa
- Departamento de Biología Celular; Facultad de Ciencias Biológicas; Center for Advanced Microscopy; CMA BIO BIO; Universidad de Concepción; Concepción Chile
| | - María García-Robles
- Departamento de Biología Celular; Facultad de Ciencias Biológicas; Center for Advanced Microscopy; CMA BIO BIO; Universidad de Concepción; Concepción Chile
| | - Fernando Martínez
- Departamento de Biología Celular; Facultad de Ciencias Biológicas; Center for Advanced Microscopy; CMA BIO BIO; Universidad de Concepción; Concepción Chile
| | - Katterine Salazar
- Departamento de Biología Celular; Facultad de Ciencias Biológicas; Center for Advanced Microscopy; CMA BIO BIO; Universidad de Concepción; Concepción Chile
| | - Karin Reinicke
- Departamento de Biología Celular; Facultad de Ciencias Biológicas; Center for Advanced Microscopy; CMA BIO BIO; Universidad de Concepción; Concepción Chile
| | - Fernando Pérez
- Hospital Regional Guillermo Grant Benavente; Concepción Chile
| | - David F. Godoy
- Facultad de Medicina; Universidad de la Frontera; Temuco Chile
| | - Alejandro S. Godoy
- Departamento de Fisiología; Pontificia Universidad Católica de Chile; Santiago Chile
- Department of Urology; Roswell Park Cancer Institute; Buffalo New York USA
| | - Francisco Nualart
- Departamento de Biología Celular; Facultad de Ciencias Biológicas; Center for Advanced Microscopy; CMA BIO BIO; Universidad de Concepción; Concepción Chile
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15
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The vitamin C transporter SVCT2 is down-regulated during postnatal development of slow skeletal muscles. Histochem Cell Biol 2013; 139:887-94. [DOI: 10.1007/s00418-012-1075-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2012] [Indexed: 02/07/2023]
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16
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Nualart F, Castro T, Low M, Henríquez JP, Oyarce K, Cisternas P, García A, Yáñez AJ, Bertinat R, Montecinos VP, García-Robles MA. Dynamic expression of the sodium-vitamin C co-transporters, SVCT1 and SVCT2, during perinatal kidney development. Histochem Cell Biol 2012; 139:233-47. [PMID: 22990596 DOI: 10.1007/s00418-012-1027-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/30/2012] [Indexed: 11/29/2022]
Abstract
Isoform 1 of the sodium-vitamin C co-transporter (SVCT1) is expressed in the apical membrane of proximal tubule epithelial cells in adult human and mouse kidneys. This study is aimed at analyzing the expression and function of SVCTs during kidney development. RT-PCR and immunohistochemical analyses revealed that SVCT1 expression is increased progressively during postnatal kidney development. However, SVCT1 transcripts were barely detected, if not absent, in the embryonic kidney. Instead, the high-affinity transporter, isoform 2 (SVCT2), was strongly expressed in the developing kidney from E15; its expression decreased at postnatal stages. Immunohistochemical analyses showed a dynamic distribution of SVCT2 in epithelial cells during kidney development. In renal cortex tubular epithelial cells, intracellular distribution of SVCT2 was observed at E19 with distribution in the basolateral membrane at P1. In contrast, SVCT2 was localized to the apical and basolateral membranes between E17 and E19 in medullary kidney tubular cells but was distributed intracellularly at P1. In agreement with these findings, functional expression of SVCT2, but not SVCT1 was detected in human embryonic kidney-derived (HEK293) cells. In addition, kinetic analysis suggested that an ascorbate-dependent mechanism accounts for targeted SVCT2 expression in the developing kidney during medullary epithelial cell differentiation. However, during cortical tubular differentiation, SVCT1 was induced and localized to the apical membrane of tubular epithelial cells. SVCT2 showed a basolateral polarization only for the first days of postnatal life. These studies suggest that the uptake of vitamin C mediated by different SVCTs plays differential roles during the ontogeny of kidney tubular epithelial cells.
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Affiliation(s)
- Francisco Nualart
- Departamento de Biología Celular, Centro de Microscopía Avanzada CMA BIO-BIO, Universidad de Concepción, Concepción, Chile.
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17
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Belin S, Kaya F, Burtey S, Fontes M. Ascorbic Acid and gene expression: another example of regulation of gene expression by small molecules? Curr Genomics 2011; 11:52-7. [PMID: 20808524 PMCID: PMC2851117 DOI: 10.2174/138920210790217936] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 09/24/2009] [Accepted: 10/22/2009] [Indexed: 01/31/2023] Open
Abstract
Ascorbic acid (vitamin C, AA) has long been considered a food supplement necessary for life and for preventing scurvy. However, it has been reported that other small molecules such as retinoic acid (vitamin A) and different forms of calciferol (vitamin D) are directly involved in regulating the expression of numerous genes. These molecules bind to receptors that are differentially expressed in the embryo and are therefore crucial signalling molecules in vertebrate development. The question is: is ascorbic acid also a signalling molecule that regulates gene expression? We therefore present and discuss recent publications that demonstrate that AA regulates the expression of a battery of genes. We offer a clue to understanding the biochemical mechanism by which AA regulates gene expression. Finally we will discuss the question of a receptor for AA and its potential involvement in embryonic development and cell differentiation.
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Affiliation(s)
- Sophie Belin
- Therapy of Genetic Disorders, EA 4263, Faculté de Médecine de la Timone, Université de la Méditerranée, Marseille, France
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18
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Corti A, Casini AF, Pompella A. Cellular pathways for transport and efflux of ascorbate and dehydroascorbate. Arch Biochem Biophys 2010; 500:107-15. [PMID: 20494648 DOI: 10.1016/j.abb.2010.05.014] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 05/13/2010] [Accepted: 05/14/2010] [Indexed: 11/17/2022]
Abstract
The mechanisms allowing the cellular transport of ascorbic acid represent a primary aspect for the understanding of the roles played by this vitamin in pathophysiology. Considerable research effort has been spent in the field, on several animal models and different cell types. Several mechanisms have been described to date, mediating the movements of different redox forms of ascorbic acid across cell membranes. Vitamin C can enter cells both in its reduced and oxidized form, ascorbic acid (AA) and dehydroascorbate (DHA), utilizing respectively sodium-dependent transporters (SVCT) or glucose transporters (GLUT). Modulation of SVCT expression and function has been described by cytokines, steroids and post-translational protein modification. Cellular uptake of DHA is followed by its intracellular reduction to AA by several enzymatic and non-enzymatic systems. Efflux of vitamin C has been also described in a number of cell types and different pathophysiological functions were proposed for this phenomenon, in dependence of the cell model studied. Cellular efflux of AA is mediated through volume-sensitive (VSOAC) and Ca(2+)-dependent anion channels, gap-junction hemichannels, exocytosis of secretory vesicles and possibly through homo- and hetero-exchange systems at the plasma membrane level. Altogether, available data suggest that cellular efflux of ascorbic acid - besides its uptake - should be taken into account when evaluating the cellular homeostasis and functions of this important vitamin.
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Affiliation(s)
- Alessandro Corti
- Dipartimento di Patologia Sperimentale, Università di Pisa, Italy.
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19
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The ascorbic acid transporter SVCT2 is expressed in slow-twitch skeletal muscle fibres. Histochem Cell Biol 2009; 131:565-74. [DOI: 10.1007/s00418-008-0552-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/07/2008] [Indexed: 10/21/2022]
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