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Vidal MS, Radnaa E, Vora N, Khanipov K, Antich C, Ferrer M, Urrabaz-Garza R, Jacob JE, Menon R. Establishment and comparison of human term placenta-derived trophoblast cells†. Biol Reprod 2024; 110:950-970. [PMID: 38330185 DOI: 10.1093/biolre/ioae026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/24/2023] [Accepted: 02/02/2024] [Indexed: 02/10/2024] Open
Abstract
Research on the biology of fetal-maternal barriers has been limited by access to physiologically relevant cells, including trophoblast cells. In this study, we describe the development of a human term placenta-derived cytotrophoblast immortalized cell line (hPTCCTB) derived from the basal plate. Human-term placenta-derived cytotrophoblast immortalized cell line cells are comparable to their primary cells of origin in terms of morphology, marker expression, and functional responses. We demonstrate that these can transform into syncytiotrophoblast and extravillous trophoblasts. We also compared the hPTCCTB cells to immortalized chorionic trophoblasts (hFM-CTC), trophoblasts of the chorionic plate, and BeWo cells, choriocarcinoma cell lines of conventional use. Human-term placenta-derived cytotrophoblast immortalized cell line and hFM-CTCs displayed more similarity to each other than to BeWos, but these differ in syncytialization ability. Overall, this study (1) demonstrates that the immortalized hPTCCTB generated are cells of higher physiological relevance and (2) provides a look into the distinction between the spatially distinct placental and fetal barrier trophoblasts cells, hPTCCTB and hFM-CTC, respectively.
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Affiliation(s)
- Manuel S Vidal
- Division of Basic Science and Translational Research, Department of Obstetrics and Gynaecology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
- Department of Biochemistry and Molecular Biology, College of Medicine, University of the Philippines Manila, Manila, Philippines
| | - Enkhtuya Radnaa
- Division of Basic Science and Translational Research, Department of Obstetrics and Gynaecology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Natasha Vora
- Division of Basic Science and Translational Research, Department of Obstetrics and Gynaecology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Kamil Khanipov
- Department of Pharmacology and Toxicology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Cristina Antich
- 3D Tissue Bioprinting Laboratory, National Center for Advancing Translational Sciences, National Institute of Sciences, Bethesda, MD, USA
| | - Marc Ferrer
- 3D Tissue Bioprinting Laboratory, National Center for Advancing Translational Sciences, National Institute of Sciences, Bethesda, MD, USA
| | - Rheanna Urrabaz-Garza
- Division of Basic Science and Translational Research, Department of Obstetrics and Gynaecology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Jeena E Jacob
- Division of Basic Science and Translational Research, Department of Obstetrics and Gynaecology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Ramkumar Menon
- Division of Basic Science and Translational Research, Department of Obstetrics and Gynaecology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
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Silva E, Ferchaud‐Roucher V, Kramer A, Madi L, Pantham P, Chassen S, Jansson T, Powell TL. Oleic acid stimulation of amino acid uptake in primary human trophoblast cells is mediated by phosphatidic acid and mTOR signaling. FASEB Bioadv 2024; 6:1-11. [PMID: 38223199 PMCID: PMC10782470 DOI: 10.1096/fba.2023-00113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 10/19/2023] [Accepted: 10/30/2023] [Indexed: 01/16/2024] Open
Abstract
Normal fetal development is critically dependent on optimal nutrient supply by the placenta, and placental amino acid transport has been demonstrated to be positively associated with fetal growth. Mechanistic target of rapamycin (mTOR) is a positive regulator of placental amino acid transporters, such as System A. Oleic acid (OA) has been previously shown to have a stimulatory role on placental mTOR signaling and System A amino acid uptake in primary human trophoblast (PHT) cells. We investigated the mechanistic link between OA and System A activity in PHT. We found that inhibition of mTOR complex 1 or 2, using small interfering RNA to knock down raptor or rictor, prevented OA-stimulated System A amino acid transport indicating the interaction of OA with mTOR. Phosphatidic acid (PA) is a key intermediary for phospholipid biosynthesis and a known regulator of the mTOR pathway; however, phospholipid biosynthetic pathways have not been extensively studied in placenta. We identified placental isoforms of acyl transferase enzymes involved in de novo phospholipid synthesis. Silencing of 1-acylglycerol-3-phosphate-O-acyltransferase-4, an enzyme in this pathway, prevented OA mediated stimulation of mTOR and System A amino acid transport. These data indicate that OA stimulates mTOR and amino acid transport in PHT cells mediated through de novo synthesis of PA. We speculate that fatty acids in the maternal circulation, such as OA, regulate placental functions critical for fetal growth by interaction with mTOR and that late pregnancy hyperlipidemia may be critical for increasing nutrient transfer to the fetus.
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Affiliation(s)
- Elena Silva
- Department of Obstetrics & GynecologyUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
| | | | - Anita Kramer
- Department of Obstetrics & GynecologyUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
| | - Lana Madi
- Department of Obstetrics & GynecologyUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
| | - Priyadarshini Pantham
- Ob/Gyn & Reproductive SciencesUniversity of California, San DiegoLa JollaCaliforniaUSA
| | - Stephanie Chassen
- Department of Pediatrics, Section of NeonatologyUniversity of Colorado, Anschutz Medical CampusAuroraColoradoUSA
| | - Thomas Jansson
- Department of Obstetrics & GynecologyUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
| | - Theresa L. Powell
- Department of Obstetrics & GynecologyUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
- Department of Pediatrics, Section of NeonatologyUniversity of Colorado, Anschutz Medical CampusAuroraColoradoUSA
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3
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Qin XY, Ha SY, Chen L, Zhang T, Li MQ. Recent Advances in Folates and Autoantibodies against Folate Receptors in Early Pregnancy and Miscarriage. Nutrients 2023; 15:4882. [PMID: 38068740 PMCID: PMC10708193 DOI: 10.3390/nu15234882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 11/13/2023] [Accepted: 11/14/2023] [Indexed: 12/18/2023] Open
Abstract
Though firstly identified in cerebral folate deficiency, autoantibodies against folate receptors (FRAbs) have been implicated in pregnancy complications such as miscarriage; however, the underlying mechanism needs to be further elaborated. FRAbs can be produced via sensitization mediated by folate-binding protein as well as gene mutation, aberrant modulation, or degradation of folate receptors (FRs). FRAbs may interfere with folate internalization and metabolism through blocking or binding with FRs. Interestingly, different types of FRs are expressed on trophoblast cells, decidual epithelium or stroma, and macrophages at the maternal-fetal interface, implying FRAbs may be involved in the critical events necessary for a successful pregnancy. Thus, we propose that FRAbs may disturb pregnancy establishment and maintenance by modulating trophoblastic biofunctions, placental development, decidualization, and decidua homeostasis as well as the functions of FOLR2+ macrophages. In light of these findings, FRAbs may be a critical factor in pathological pregnancy, and deserve careful consideration in therapies involving folic acid supplementation for pregnancy complications.
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Affiliation(s)
- Xue-Yun Qin
- Laboratory for Reproductive Immunology, Hospital of Obstetrics and Gynecology, Fudan University, Shanghai 200080, China; (X.-Y.Q.); (S.-Y.H.)
| | - Si-Yao Ha
- Laboratory for Reproductive Immunology, Hospital of Obstetrics and Gynecology, Fudan University, Shanghai 200080, China; (X.-Y.Q.); (S.-Y.H.)
| | - Lu Chen
- Assisted Reproductive Technology Unit, Department of Obstetrics and Gynecology, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong 999077, China;
| | - Tao Zhang
- Assisted Reproductive Technology Unit, Department of Obstetrics and Gynecology, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong 999077, China;
| | - Ming-Qing Li
- Laboratory for Reproductive Immunology, Hospital of Obstetrics and Gynecology, Fudan University, Shanghai 200080, China; (X.-Y.Q.); (S.-Y.H.)
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Hospital of Obstetrics and Gynecology, Fudan University, Shanghai 200080, China
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Singh DK, Bhaskar A, Pahuja I, Shaji A, Moitra B, Shi Y, Dwivedi VP, Das G. Cotreatment With Clofazimine and Rapamycin Eliminates Drug-Resistant Tuberculosis by Inducing Polyfunctional Central Memory T-Cell Responses. J Infect Dis 2023; 228:1166-1178. [PMID: 37290049 DOI: 10.1093/infdis/jiad214] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/10/2023] [Accepted: 06/07/2023] [Indexed: 06/10/2023] Open
Abstract
Mycobacterium tuberculosis, the causative agent of tuberculosis, is acquiring drug resistance at a faster rate than the discovery of new antibiotics. Therefore, alternate therapies that can limit the drug resistance and disease recurrence are urgently needed. Emerging evidence indicates that combined treatment with antibiotics and an immunomodulator provides superior treatment efficacy. Clofazimine (CFZ) enhances the generation of T central memory (TCM) cells by blocking the Kv1.3+ potassium channels. Rapamycin (RAPA) facilitates M. tuberculosis clearance by inducing autophagy. In this study, we observed that cotreatment with CFZ and RAPA potently eliminates both multiple and extensively drug-resistant (MDR and XDR) clinical isolates of M. tuberculosis in a mouse model by inducing robust T-cell memory and polyfunctional TCM responses. Furthermore, cotreatment reduces the expression of latency-associated genes of M. tuberculosis in human macrophages. Therefore, CFZ and RAPA cotherapy holds promise for treating patients infected with MDR and XDR strains of M. tuberculosis.
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Affiliation(s)
- Dhiraj Kumar Singh
- Immunobiology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
- Special Center for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Ashima Bhaskar
- Immunobiology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Isha Pahuja
- Immunobiology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Aishwarya Shaji
- Immunobiology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Barnani Moitra
- Special Center for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Yufang Shi
- State Key Laboratory of Radiation Medicine and Protection, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Ved Prakash Dwivedi
- Immunobiology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Gobardhan Das
- Special Center for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
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Kramer AC, Jansson T, Bale TL, Powell TL. Maternal-fetal cross-talk via the placenta: influence on offspring development and metabolism. Development 2023; 150:dev202088. [PMID: 37831056 PMCID: PMC10617615 DOI: 10.1242/dev.202088] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Compelling epidemiological and animal experimental data demonstrate that cardiometabolic and neuropsychiatric diseases originate in a suboptimal intrauterine environment. Here, we review evidence suggesting that altered placental function may, at least in part, mediate the link between the maternal environment and changes in fetal growth and development. Emerging evidence indicates that the placenta controls the development and function of several fetal tissues through nutrient sensing, modulation of trophoblast nutrient transporters and by altering the number and cargo of released extracellular vesicles. In this Review, we discuss the development and functions of the maternal-placental-fetal interface (in humans and mice) and how cross-talk between these compartments may be a mechanism for in utero programming, focusing on mechanistic target of rapamycin (mTOR), adiponectin and O-GlcNac transferase (OGT) signaling. We also discuss how maternal diet and stress influences fetal development and metabolism and how fetal growth restriction can result in susceptibility to developing chronic disease later in life. Finally, we speculate how interventions targeting placental function may offer unprecedented opportunities to prevent cardiometabolic disease in future generations.
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Affiliation(s)
- Avery C. Kramer
- Departments of Obstetrics & Gynecology, Psychiatry and Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA
| | - Thomas Jansson
- Departments of Obstetrics & Gynecology, Psychiatry and Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA
| | - Tracy L. Bale
- Departments of Obstetrics & Gynecology, Psychiatry and Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA
| | - Theresa L. Powell
- Departments of Obstetrics & Gynecology, Psychiatry and Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA
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Rosario FJ, Chopra A, Biggar K, Powell TL, Gupta MB, Jansson T. Placental Remote Control of Fetal Metabolism: Trophoblast mTOR Signaling Regulates Liver IGFBP-1 Phosphorylation and IGF-1 Bioavailability. Int J Mol Sci 2023; 24:7273. [PMID: 37108437 PMCID: PMC10138459 DOI: 10.3390/ijms24087273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 04/02/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
The mechanisms mediating the restricted growth in intrauterine growth restriction (IUGR) remain to be fully established. Mechanistic target of rapamycin (mTOR) signaling functions as a placental nutrient sensor, indirectly influencing fetal growth by regulating placental function. Increased secretion and the phosphorylation of fetal liver IGFBP-1 are known to markedly decrease the bioavailability of IGF-1, a major fetal growth factor. We hypothesized that an inhibition of trophoblast mTOR increases liver IGFBP-1 secretion and phosphorylation. We collected conditioned media (CM) from cultured primary human trophoblast (PHT) cells with a silenced RAPTOR (specific inhibition of mTOR Complex 1), RICTOR (inhibition of mTOR Complex 2), or DEPTOR (activates both mTOR Complexes). Subsequently, HepG2 cells, a well-established model for human fetal hepatocytes, were cultured in CM from PHT cells, and IGFBP-1 secretion and phosphorylation were determined. CM from PHT cells with either mTORC1 or mTORC2 inhibition caused the marked hyperphosphorylation of IGFBP-1 in HepG2 cells as determined by 2D-immunoblotting while Parallel Reaction Monitoring-Mass Spectrometry (PRM-MS) identified increased dually phosphorylated Ser169 + Ser174. Furthermore, using the same samples, PRM-MS identified multiple CK2 peptides coimmunoprecipitated with IGFBP-1 and greater CK2 autophosphorylation, indicating the activation of CK2, a key enzyme mediating IGFBP-1 phosphorylation. Increased IGFBP-1 phosphorylation inhibited IGF-1 function, as determined by the reduced IGF-1R autophosphorylation. Conversely, CM from PHT cells with mTOR activation decreased IGFBP-1 phosphorylation. CM from non-trophoblast cells with mTORC1 or mTORC2 inhibition had no effect on HepG2 IGFBP-1 phosphorylation. Placental mTOR signaling may regulate fetal growth by the remote control of fetal liver IGFBP-1 phosphorylation.
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Affiliation(s)
- Fredrick J. Rosario
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Anand Chopra
- Institute of Biochemistry, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Kyle Biggar
- Institute of Biochemistry, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Theresa L. Powell
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Department of Biochemistry, University of Western Ontario, London, ON N6A 3K7, Canada
| | - Madhulika B. Gupta
- Department of Biochemistry, University of Western Ontario, London, ON N6A 3K7, Canada
- Department of Pediatrics, University of Western Ontario, London, ON N6A 3K7, Canada
- Children’s Health Research Institute, University of Western Ontario, London, ON N6A 3K7, Canada
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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Wang G, Chen L, Qin S, Zhang T, Yao J, Yi Y, Deng L. Mechanistic Target of Rapamycin Complex 1: From a Nutrient Sensor to a Key Regulator of Metabolism and Health. Adv Nutr 2022; 13:1882-1900. [PMID: 35561748 PMCID: PMC9526850 DOI: 10.1093/advances/nmac055] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 04/26/2022] [Accepted: 05/09/2022] [Indexed: 01/28/2023] Open
Abstract
Mechanistic target of rapamycin complex 1 (mTORC1) is a multi-protein complex widely found in eukaryotes. It serves as a central signaling node to coordinate cell growth and metabolism by sensing diverse extracellular and intracellular inputs, including amino acid-, growth factor-, glucose-, and nucleotide-related signals. It is well documented that mTORC1 is recruited to the lysosomal surface, where it is activated and, accordingly, modulates downstream effectors involved in regulating protein, lipid, and glucose metabolism. mTORC1 is thus the central node for coordinating the storage and mobilization of nutrients and energy across various tissues. However, emerging evidence indicated that the overactivation of mTORC1 induced by nutritional disorders leads to the occurrence of a variety of metabolic diseases, including obesity and type 2 diabetes, as well as cancer, neurodegenerative disorders, and aging. That the mTORC1 pathway plays a crucial role in regulating the occurrence of metabolic diseases renders it a prime target for the development of effective therapeutic strategies. Here, we focus on recent advances in our understanding of the regulatory mechanisms underlying how mTORC1 integrates metabolic inputs as well as the role of mTORC1 in the regulation of nutritional and metabolic diseases.
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Affiliation(s)
- Guoyan Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China
| | - Lei Chen
- Division of Laboratory Safety and Services, Northwest A&F University, Yangling Shaanxi, China
| | - Senlin Qin
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China
| | - Tingting Zhang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Junhu Yao
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China
| | - Yanglei Yi
- Address correspondence to YLY (e-mail: )
| | - Lu Deng
- Address correspondence to LD (e-mail: )
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Liu Y, Zhang Q, Gao X, Wang T. Study on lipid nanomicelles targeting placenta for the treatment of preeclampsia. J Drug Target 2022; 30:894-909. [PMID: 35502921 DOI: 10.1080/1061186x.2022.2068558] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In view of the serious clinical harm of preeclampsia and the lack of effective treatment methods, a PEG-modified lipid hybrid micelle was designed with folic acid molecule on the surface, containing siRNA, targeted delivery to the placenta, interfering the expression of sFlt-1 and treating preeclampsia. In this paper, the preparation and characterization of lipid hybrid micelles were investigated in detail, the cytology in vitro and in vivo distribution, pharmacodynamics, safety and action mechanism of the preparation were studied, which laid a foundation for gene therapy of preeclampsia.
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Affiliation(s)
- Yang Liu
- School of Pharmaceutical Sciences, Zhengzhou University, No.100, Kexue Avenue, Zhengzhou 450001, China
| | - Qimeng Zhang
- School of Pharmaceutical Sciences, Zhengzhou University, No.100, Kexue Avenue, Zhengzhou 450001, China
| | - Xingli Gao
- School of Pharmaceutical Sciences, Zhengzhou University, No.100, Kexue Avenue, Zhengzhou 450001, China
| | - Tong Wang
- School of Pharmaceutical Sciences, Zhengzhou University, No.100, Kexue Avenue, Zhengzhou 450001, China
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Nema J, Joshi N, Sundrani D, Joshi S. Influence of maternal one carbon metabolites on placental programming and long term health. Placenta 2022; 125:20-28. [DOI: 10.1016/j.placenta.2022.02.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 02/12/2022] [Accepted: 02/24/2022] [Indexed: 10/18/2022]
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10
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Blanco-Castañeda R, Zapata-Vázquez Y, Lazalde-Ramos BP, Enríquez-Mendiola D, Lares-Asseff I, Galaviz-Hernández C, Martínez G, Sosa-Macías M. Effect of levetiracetam on the gene expression of placental transporters in a murine model. Epilepsia 2022; 63:1266-1275. [PMID: 35174498 DOI: 10.1111/epi.17195] [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: 10/13/2021] [Revised: 02/02/2022] [Accepted: 02/02/2022] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Levetiracetam (LEV) is an antiseizure medication prescribed to women during childbearing age. The impact of LEV on placental transporters is poorly understood. This study aimed to assess the effect of LEV exposure on the messenger RNA (mRNA) expression of placental transporters for hormones and nutrients and to correlate their expression with the drug's serum concentration in pregnant mice. METHODS Studies were conducted on gestational days (GD) 13 and 18, following oral treatment with 100 mg/kg LEV or the vehicle every 24 h after weaning. Serum LEV measurements were performed by High-performance liquid chromatography with a UV detector (HPLC-UV). The weight, height, and width of the fetuses were also analyzed. In addition, the placental expression of transporters xCt, Lat1, Oatp4a1, Fr-α, Rfc, and Snat4 was evaluated through semi-quantitative real-time polymerase chain reaction (qPCR). The Kruskal-Wallis and the Mann-Whitney U tests were used to determine the statistical significance (p < .05). The correlation between serum LEV concentration and placental gene expression was evaluated using the Spearman test. RESULTS The weight, height, and width were lower in the fetuses exposed to LEV compared with the control group (p < .05). The number of fetuses was lower in the LEV-exposed group than in the control GD 13 group (p < .001). No significant differences were detected in the mRNA expression level at GD 13. At GD 18, the expression of Lat1, Oatp4a1, xCT, and Snat4 was higher in the group treated with LEV compared with the control group (p < .05), whereas the expression of Rfc was lower (p < .05). No correlation was identified between serum LEV concentrations and gene expression levels. SIGNIFICANCE The repression of the Rfc transcript by LEV at GD 18 suggests that the protein expression would be abolished contributing to the observed intrauterine growth restriction (IUGR). Furthermore, the significant increase in mRNA of xCt, Snat4, Oatp4a1, and Lat1 might be a compensatory mechanism for fetal survival at GD 18.
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Affiliation(s)
| | - Yessica Zapata-Vázquez
- Laboratory of Biomedical Ethnopharmacology, Academic Unit of Chemical Sciences, Autonomous University of Zacatecas, Zacatecas, Mexico
| | - Blanca P Lazalde-Ramos
- Laboratory of Biomedical Ethnopharmacology, Academic Unit of Chemical Sciences, Autonomous University of Zacatecas, Zacatecas, Mexico
| | | | - Ismael Lares-Asseff
- Genomics Academy, CIIDIR Durango Unit, National Polytechnic Institute, Durango, Mexico
| | | | - Gerardo Martínez
- Biomedical Research Unit - Mexican Institute of Social Security (IMSS) Durango, Durango, Mexico
| | - Martha Sosa-Macías
- Genomics Academy, CIIDIR Durango Unit, National Polytechnic Institute, Durango, Mexico
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Tanaka K, Tanaka H, Tachibana R, Yoshikawa K, Kawamura T, Takakura S, Takeuchi H, Ikeda T. Tadalafil Treatment of Mice with Fetal Growth Restriction and Preeclampsia Improves Placental mTOR Signaling. Int J Mol Sci 2022; 23:ijms23031474. [PMID: 35163395 PMCID: PMC8835936 DOI: 10.3390/ijms23031474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 12/10/2022] Open
Abstract
Fetal growth restriction (FGR) is a major cause of poor perinatal outcomes. Although several studies have been conducted to improve the prognosis of FGR in infants, no effective intrauterine treatment method has been established. This study aimed to use tadalafil, a phosphodiesterase 5 inhibitor (PDE5) inhibitor, as a novel intrauterine treatment and conducted several basic and clinical studies. The study investigated the effects of tadalafil on placental mTOR signaling. Tadalafil was administered to mice with L-NG-nitroarginine methyl ester (L-NAME)-induced FGR and associated preeclampsia (PE). Placental phosphorylated mTOR (p-mTOR) signaling was assessed by fluorescent immunohistochemical staining and Western blotting. The expression of p-mTOR was significantly decreased in mice with FGR on 13 days post coitum (d.p.c.) but recovered to the same level as that of the control on 17 d.p.c. following tadalafil treatment. The results were similar for 4E-binding protein 1 (4E-BP1) and S6 ribosomal (S6R) protein, which act downstream in the mTOR signaling pathway. We demonstrate that the tadalafil treatment of FGR in mice improved placental mTOR signaling to facilitate fetal growth. Our study provides the key mechanistic detail about the mode of action of tadalafil and thus would be helpful for future clinical studies on FGR.
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Affiliation(s)
| | - Hiroaki Tanaka
- Correspondence: ; Tel.: +81-59-232-1111; Fax: +81-59-231-5202
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12
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Francis EC, Dabelea D, Boyle KE, Jansson T, Perng W. Maternal Diet Quality Is Associated with Placental Proteins in the Placental Insulin/Growth Factor, Environmental Stress, Inflammation, and mTOR Signaling Pathways: The Healthy Start ECHO Cohort. J Nutr 2021; 152:816-825. [PMID: 34850052 PMCID: PMC8891174 DOI: 10.1093/jn/nxab403] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 10/19/2021] [Accepted: 11/23/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Maternal nutritional status affects placental function, which may underlie the intrauterine origins of obesity and diabetes. The extent to which diet quality is associated with placental signaling and which specific pathways are impacted is unknown. OBJECTIVES To examine sex-specific associations of maternal diet quality according to the Healthy Eating Index (HEI)-developed to align with recommendations from the Dietary Guidelines for Americans-with placental proteins involved in metabolism and mediators of environmental stress, inflammation, and growth factors. METHODS Among 108 women from the Healthy Start cohort with a mean ± SD age of 29.0 ± 6.1 y and a prepregnancy BMI (in kg/m2) of 24.8 ± 5.3, we conducted multivariable linear regression analysis stratified by offspring sex. We adjusted for maternal race or ethnicity, age, education, prenatal smoking habits, and physical activity and tested for an association of maternal HEI >57 compared with ≤57 and the abundance and phosphorylation of key proteins involved in insulin/growth factor signaling; mediators of environmental stress, inflammation, and growth factors; mechanistic target of rapamycin signaling proteins; and energy sensing in placental villus samples. HEI >57 was chosen given its prior relevance among Healthy Start mother-child dyads. RESULTS In adjusted models, HEI >57 was associated with greater abundance of insulin receptor β (0.80; 95% CI: 0.11, 1.49) in placentas of females. In males, maternal HEI >57 was associated with greater activation and abundance of select placental nutrient-sensing proteins and environmental stress, inflammation, and growth factor proteins (S6K1Thr389/S6K1: 0.81; 95% CI: 0.21, 1.41; JNK1Thr183/Tyr185/JNK1: 0.82; 95% CI: 0.27, 1.37; JNK2Thr183/Tyr185/JNK2: 0.57; 95% CI: 0.02, 1.11). CONCLUSIONS Higher-quality diet had sex-specific associations with placental protein abundance/phosphorylation. Given that these proteins have been correlated with neonatal anthropometry, our findings provide insight into modifiable factors and placental pathways that should be examined in future studies as potential links between maternal diet and offspring metabolic health. This trial was registered at clinicaltrials.gov as NCT02273297.
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Affiliation(s)
| | - Dana Dabelea
- The Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, Aurora, CO, USA,Department of Epidemiology, Colorado School of Public Health, University of Colorado Denver Anschutz Medical Campus, Aurora, CO, USA,Department of Pediatrics, School of Medicine, University of Colorado Denver Anschutz Medical Campus, Aurora, CO, USA
| | - Kristen E Boyle
- The Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, Aurora, CO, USA,Section of Nutrition, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Thomas Jansson
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Wei Perng
- The Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, Aurora, CO, USA,Section of Nutrition, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA,Deptartment of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, MI, USA
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13
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Rosario FJ, Kelly AC, Gupta MB, Powell TL, Cox L, Jansson T. Mechanistic Target of Rapamycin Complex 2 Regulation of the Primary Human Trophoblast Cell Transcriptome. Front Cell Dev Biol 2021; 9:670980. [PMID: 34805133 PMCID: PMC8599300 DOI: 10.3389/fcell.2021.670980] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 09/23/2021] [Indexed: 01/04/2023] Open
Abstract
Mechanistic Target of Rapamycin Complex 2 (mTORC2) regulates placental amino acid and folate transport. However, the role of mTORC2 in modulating other placental functions is largely unexplored. We used a gene array following the silencing of rictor to identify genes regulated by mTORC2 in primary human trophoblast (PHT) cells. Four hundred and nine genes were differentially expressed; 102 genes were down-regulated and 307 up-regulated. Pathway analyses demonstrated that inhibition of mTORC2 resulted in increased expression of genes encoding for pro-inflammatory IL-6, VEGF-A, leptin, and inflammatory signaling (SAPK/JNK). Furthermore, down-regulated genes were functionally enriched in genes involved in angiogenesis (Osteopontin) and multivitamin transport (SLC5A6). In addition, the protein expression of leptin, VEGFA, IL-6 was increased and negatively correlated to mTORC2 signaling in human placentas collected from pregnancies complicated by intrauterine growth restriction (IUGR). In contrast, the protein expression of Osteopontin and SLC5A6 was decreased and positively correlated to mTORC2 signaling in human IUGR placentas. In conclusion, mTORC2 signaling regulates trophoblast expression of genes involved in inflammation, micronutrient transport, and angiogenesis, representing novel links between mTOR signaling and multiple placental functions necessary for fetal growth and development.
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Affiliation(s)
- Fredrick J Rosario
- Division of Reproductive Sciences, Department of OB/GYN University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Amy Catherine Kelly
- Division of Reproductive Sciences, Department of OB/GYN University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Madhulika B Gupta
- Children's Health Research Institute and Department of Pediatrics and Biochemistry, University of Western Ontario, London, ON, Canada
| | - Theresa L Powell
- Division of Reproductive Sciences, Department of OB/GYN University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Laura Cox
- Section of Molecular Medicine, Department of Internal Medicine, Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of OB/GYN University of Colorado Anschutz Medical Campus, Aurora, CO, United States
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Interaction between Metformin, Folate and Vitamin B 12 and the Potential Impact on Fetal Growth and Long-Term Metabolic Health in Diabetic Pregnancies. Int J Mol Sci 2021; 22:ijms22115759. [PMID: 34071182 PMCID: PMC8198407 DOI: 10.3390/ijms22115759] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 12/15/2022] Open
Abstract
Metformin is the first-line treatment for many people with type 2 diabetes mellitus (T2DM) and gestational diabetes mellitus (GDM) to maintain glycaemic control. Recent evidence suggests metformin can cross the placenta during pregnancy, thereby exposing the fetus to high concentrations of metformin and potentially restricting placental and fetal growth. Offspring exposed to metformin during gestation are at increased risk of being born small for gestational age (SGA) and show signs of ‘catch up’ growth and obesity during childhood which increases their risk of future cardiometabolic diseases. The mechanisms by which metformin impacts on the fetal growth and long-term health of the offspring remain to be established. Metformin is associated with maternal vitamin B12 deficiency and antifolate like activity. Vitamin B12 and folate balance is vital for one carbon metabolism, which is essential for DNA methylation and purine/pyrimidine synthesis of nucleic acids. Folate:vitamin B12 imbalance induced by metformin may lead to genomic instability and aberrant gene expression, thus promoting fetal programming. Mitochondrial aerobic respiration may also be affected, thereby inhibiting placental and fetal growth, and suppressing mammalian target of rapamycin (mTOR) activity for cellular nutrient transport. Vitamin supplementation, before or during metformin treatment in pregnancy, could be a promising strategy to improve maternal vitamin B12 and folate levels and reduce the incidence of SGA births and childhood obesity. Heterogeneous diagnostic and screening criteria for GDM and the transient nature of nutrient biomarkers have led to inconsistencies in clinical study designs to investigate the effects of metformin on folate:vitamin B12 balance and child development. As rates of diabetes in pregnancy continue to escalate, more women are likely to be prescribed metformin; thus, it is of paramount importance to improve our understanding of metformin’s transgenerational effects to develop prophylactic strategies for the prevention of adverse fetal outcomes.
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15
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Placental trophoblast syncytialization potentiates macropinocytosis via mTOR signaling to adapt to reduced amino acid supply. Proc Natl Acad Sci U S A 2021; 118:2017092118. [PMID: 33402432 DOI: 10.1073/pnas.2017092118] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
During pregnancy, the appropriate allocation of nutrients between the mother and the fetus is dominated by maternal-fetal interactions, which is primarily governed by the placenta. The syncytiotrophoblast (STB) lining at the outer surface of the placental villi is directly bathed in maternal blood and controls feto-maternal exchange. The STB is the largest multinucleated cell type in the human body, and is formed through syncytialization of the mononucleated cytotrophoblast. However, the physiological advantage of forming such an extensively multinucleated cellular structure remains poorly understood. Here, we discover that the STB uniquely adapts to nutrient stress by inducing the macropinocytosis machinery through repression of mammalian target of rapamycin (mTOR) signaling. In primary human trophoblasts and in trophoblast cell lines, differentiation toward a syncytium triggers macropinocytosis, which is greatly enhanced during amino acid shortage, induced by inhibiting mTOR signaling. Moreover, inhibiting mTOR in pregnant mice markedly stimulates macropinocytosis in the syncytium. Blocking macropinocytosis worsens the phenotypes of fetal growth restriction caused by mTOR-inhibition. Consistently, placentas derived from fetal growth restriction patients display: 1) Repressed mTOR signaling, 2) increased syncytialization, and 3) enhanced macropinocytosis. Together, our findings suggest that the unique ability of STB to undergo macropinocytosis serves as an essential adaptation to the cellular nutrient status, and support fetal survival and growth under nutrient deprivation.
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16
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Inhibition of mechanistic target of rapamycin signaling decreases levels of O-GlcNAc transferase and increases serotonin release in the human placenta. Clin Sci (Lond) 2021; 134:3123-3136. [PMID: 33215629 DOI: 10.1042/cs20201050] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/02/2020] [Accepted: 11/20/2020] [Indexed: 12/13/2022]
Abstract
Changes in placental function, in particular down-regulation of placental O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) in response to maternal stress and increased placental secretion of serotonin into the fetal circulation following maternal infection, have been mechanistically linked to adverse neurodevelopment in mice. We hypothesized that mechanistic target of rapamycin (mTOR) signaling is a key regulator of trophoblast serotonin synthesis and OGT protein expression and that serotonin is secreted by the human placenta into the fetal circulation. Placental homogenates (n=46) from elective terminations at 8-22 weeks of gestation and from healthy-term women were sexed and the protein levels of OGT and enzymes involved in serotonin synthesis was determined. Primary human trophoblast (PHT) cells were isolated from normal term placenta (n=27), cultured and transfected (n=8) with siRNA targeting a scramble sequence (control), raptor (inhibits mTOR Complex 1 (mTORC1)), or rictor (inhibits mTOR Complex 2 (mTORC2)). Subsequently, conditioned media and PHT cell lysates were collected. Free serotonin concentration was measured using ELISA in cell culture media and in platelet-depleted normal term umbilical vein and artery plasma (n=38). Both mTORC1 and mTORC2 inhibition down-regulated OGT levels in PHT cells. The level of serotonin synthesis enzyme tryptophan hydroxylase (TPH-1) was higher in early gestation female placentas and at term serotonin concentration was three-fold higher in the umbilical vein than in the umbilical artery. Inhibition of mTORC2, but not mTORC1, increased cultured PHT cell serotonin secretion. Our data are consistent with the model that mTOR signaling is a key regulator of trophoblast serotonin synthesis and OGT protein expression.
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Abstract
Cells metabolize nutrients for biosynthetic and bioenergetic needs to fuel growth and proliferation. The uptake of nutrients from the environment and their intracellular metabolism is a highly controlled process that involves cross talk between growth signaling and metabolic pathways. Despite constant fluctuations in nutrient availability and environmental signals, normal cells restore metabolic homeostasis to maintain cellular functions and prevent disease. A central signaling molecule that integrates growth with metabolism is the mechanistic target of rapamycin (mTOR). mTOR is a protein kinase that responds to levels of nutrients and growth signals. mTOR forms two protein complexes, mTORC1, which is sensitive to rapamycin, and mTORC2, which is not directly inhibited by this drug. Rapamycin has facilitated the discovery of the various functions of mTORC1 in metabolism. Genetic models that disrupt either mTORC1 or mTORC2 have expanded our knowledge of their cellular, tissue, as well as systemic functions in metabolism. Nevertheless, our knowledge of the regulation and functions of mTORC2, particularly in metabolism, has lagged behind. Since mTOR is an important target for cancer, aging, and other metabolism-related pathologies, understanding the distinct and overlapping regulation and functions of the two mTOR complexes is vital for the development of more effective therapeutic strategies. This review discusses the key discoveries and recent findings on the regulation and metabolic functions of the mTOR complexes. We highlight findings from cancer models but also discuss other examples of the mTOR-mediated metabolic reprogramming occurring in stem and immune cells, type 2 diabetes/obesity, neurodegenerative disorders, and aging.
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Affiliation(s)
- Angelia Szwed
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Eugene Kim
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Estela Jacinto
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
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18
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Rosario FJ, Powell TL, Gupta MB, Cox L, Jansson T. mTORC1 Transcriptional Regulation of Ribosome Subunits, Protein Synthesis, and Molecular Transport in Primary Human Trophoblast Cells. Front Cell Dev Biol 2020; 8:583801. [PMID: 33324640 PMCID: PMC7726231 DOI: 10.3389/fcell.2020.583801] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 10/20/2020] [Indexed: 12/12/2022] Open
Abstract
Mechanistic Target of Rapamycin Complex 1 (mTORC1) serves as positive regulator of placental nutrient transport and mitochondrial respiration. The role of mTORC1 signaling in modulating other placental functions is largely unexplored. We used gene array following silencing of raptor to identify genes regulated by mTORC1 in primary human trophoblast (PHT) cells. Seven hundred and thirty-nine genes were differentially expressed; 487 genes were down-regulated and 252 up-regulated. Bioinformatic analyses demonstrated that inhibition of mTORC1 resulted in decreased expression of genes encoding ribosomal proteins in the 60S and 40S ribosome subunits. Furthermore, down-regulated genes were functionally enriched in genes involved in eIF2, sirtuin and mTOR signaling, mitochondrial function, and glutamine and zinc transport. Stress response genes were enriched among up-regulated genes following mTORC1 inhibition. The protein expression of ribosomal proteins RPL26 (RPL26) and Ribosomal Protein S10 (RPS10) was decreased and positively correlated to mTORC1 signaling and System A amino acid transport in human placentas collected from pregnancies complicated by intrauterine growth restriction (IUGR). In conclusion, mTORC1 signaling regulates the expression of trophoblast genes involved in ribosome and protein synthesis, mitochondrial function, lipid metabolism, nutrient transport, and angiogenesis, representing novel links between mTOR signaling and multiple placental functions critical for normal fetal growth and development.
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Affiliation(s)
- Fredrick J. Rosario
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Theresa L. Powell
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Madhulika B. Gupta
- Department of Biochemistry, University of Western Ontario, London, ON, Canada
| | - Laura Cox
- Center for Precision Medicine, Department of Internal Medicine, Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
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19
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Gupta MB, Jansson T. Novel roles of mechanistic target of rapamycin signaling in regulating fetal growth†. Biol Reprod 2020; 100:872-884. [PMID: 30476008 DOI: 10.1093/biolre/ioy249] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 11/08/2018] [Accepted: 11/19/2018] [Indexed: 12/18/2022] Open
Abstract
Mechanistic target of rapamycin (mTOR) signaling functions as a central regulator of cellular metabolism, growth, and survival in response to hormones, growth factors, nutrients, energy, and stress signals. Mechanistic TOR is therefore critical for the growth of most fetal organs, and global mTOR deletion is embryonic lethal. This review discusses emerging evidence suggesting that mTOR signaling also has a role as a critical hub in the overall homeostatic control of fetal growth, adjusting the fetal growth trajectory according to the ability of the maternal supply line to support fetal growth. In the fetus, liver mTOR governs the secretion and phosphorylation of insulin-like growth factor binding protein 1 (IGFBP-1) thereby controlling the bioavailability of insulin-like growth factors (IGF-I and IGF-II), which function as important growth hormones during fetal life. In the placenta, mTOR responds to a large number of growth-related signals, including amino acids, glucose, oxygen, folate, and growth factors, to regulate trophoblast mitochondrial respiration, nutrient transport, and protein synthesis, thereby influencing fetal growth. In the maternal compartment, mTOR is an integral part of a decidual nutrient sensor which links oxygen and nutrient availability to the phosphorylation of IGFBP-1 with preferential effects on the bioavailability of IGF-I in the maternal-fetal interface and in the maternal circulation. These new roles of mTOR signaling in the regulation fetal growth will help us better understand the molecular underpinnings of abnormal fetal growth, such as intrauterine growth restriction and fetal overgrowth, and may represent novel avenues for diagnostics and intervention in important pregnancy complications.
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Affiliation(s)
- Madhulika B Gupta
- Department of Pediatrics, University of Western Ontario, London, Ontario, Canada.,Department of Biochemistry, University of Western Ontario, London, Ontario, Canada.,Children's Health Research Institute, London, Ontario, Canada
| | - Thomas Jansson
- Department of Obstetrics and Gynecology, Division of Reproductive Sciences, University of Colorado
- Anschutz Medical Campus, Aurora, Colorado, USA
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20
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Jessel RH, Rosario FJ, Chen YY, Erickson K, Teal SB, Kramer A, Cotton E, Ryan S, Jansson T, Powell TL. Decreased placental folate transporter expression and activity in first and second trimester in obese mothers. J Nutr Biochem 2019; 77:108305. [PMID: 31926453 DOI: 10.1016/j.jnutbio.2019.108305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 11/19/2019] [Accepted: 11/21/2019] [Indexed: 10/25/2022]
Abstract
Obese women have an approximately twofold higher risk to deliver an infant with neural tube defects (NTDs) despite folate supplementation. Placental transfer of folate is mediated by folate receptor alpha (FR-α), proton coupled folate transporter (PCFT), and reduced folate carrier (RFC). Decreased placental transport may contribute to NTDs in obese women. Serum folate levels were measured and placental tissue was collected from 13 women with normal BMI (21.9±1.9) and 11 obese women (BMI 33.1±2.8) undergoing elective termination at 8-22 weeks of gestation. The syncytiotrophoblast microvillous plasma membranes (MVM) were isolated using homogenization, magnesium precipitation, and differential centrifugation. MVM expression of FR-α, PCFT and RFC was determined by western blot. Folate transport capacity was assessed using radiolabeled methyl-tetrahydrofolate and rapid filtration techniques. Differences in expression and transport capacity were adjusted for gestational age and maternal age in multivariable regression models. P<.05 was considered statistically significant. Serum folate levels were not significantly different between groups. Placental MVM folate transporter expression did not change with gestational age. MVM RFC (-19%) and FR-α (-17%) expression was significantly reduced in placentas from obese women (P<.05). MVM folate transporter activity was reduced by-52% (P<.05) in obese women. These differences remained after adjustment for gestational age. There was no difference in mTOR signaling between groups. In conclusion, RFC and FR alpha expression and transporter activity in the placental MVM are significantly reduced in obese women in early pregnancy. These results may explain the higher incidence of NTDs in infants of obese women with adequate serum folate.
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Affiliation(s)
- Rebecca H Jessel
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO; Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO.
| | - Fredrick J Rosario
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Yi-Yung Chen
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO; Division of High-risk Pregnancy, Department of Obstetrics & Gynecology, Mackay Memorial Hospital, Taipei, Taiwan
| | - Kathryn Erickson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Stephanie B Teal
- Division of Family Planning, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Anita Kramer
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Eleanor Cotton
- Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Sarah Ryan
- Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Theresa L Powell
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO; Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO
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21
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Merech F, Soczewski E, Hauk V, Paparini D, Ramhorst R, Vota D, Pérez Leirós C. Vasoactive Intestinal Peptide induces glucose and neutral amino acid uptake through mTOR signalling in human cytotrophoblast cells. Sci Rep 2019; 9:17152. [PMID: 31748639 PMCID: PMC6868285 DOI: 10.1038/s41598-019-53676-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 10/31/2019] [Indexed: 11/21/2022] Open
Abstract
The transport of nutrients across the placenta involves trophoblast cell specific transporters modulated through the mammalian target of rapamycin (mTOR). The vasoactive intestinal peptide (VIP) has embryotrophic effects in mice and regulates human cytotrophoblast cell migration and invasion. Here we explored the effect of VIP on glucose and System A amino acid uptake by human trophoblast-derived cells (Swan 71 and BeWo cell lines). VIP activated D-glucose specific uptake in single cytotrophoblast cells in a concentration-dependent manner through PKA, MAPK, PI3K and mTOR signalling pathways. Glucose uptake was reduced in VIP-knocked down cytotrophoblast cells. Also, VIP stimulated System A amino acid uptake and the expression of GLUT1 glucose transporter and SNAT1 neutral amino acid transporter. VIP increased mTOR expression and mTOR/S6 phosphorylation whereas VIP silencing reduced mTOR mRNA and protein expression. Inhibition of mTOR signalling with rapamycin reduced the expression of endogenous VIP and of VIP-induced S6 phosphorylation. Our findings support a role of VIP in the transport of glucose and neutral amino acids in cytotrophoblast cells through mTOR-regulated pathways and they are instrumental for understanding the physiological regulation of nutrient sensing by endogenous VIP at the maternal-foetal interface.
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Affiliation(s)
- Fatima Merech
- CONICET - Universidad de Buenos Aires. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Elizabeth Soczewski
- CONICET - Universidad de Buenos Aires. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Vanesa Hauk
- CONICET - Universidad de Buenos Aires. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Daniel Paparini
- CONICET - Universidad de Buenos Aires. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Rosanna Ramhorst
- CONICET - Universidad de Buenos Aires. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Daiana Vota
- CONICET - Universidad de Buenos Aires. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Claudia Pérez Leirós
- CONICET - Universidad de Buenos Aires. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina.
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22
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Vaughan OR, Powell TL, Jansson T. Glucocorticoid regulation of amino acid transport in primary human trophoblast cells. J Mol Endocrinol 2019; 63:239-248. [PMID: 31505460 PMCID: PMC6872941 DOI: 10.1530/jme-19-0183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 09/10/2019] [Indexed: 12/20/2022]
Abstract
Excess maternal glucocorticoids reduce placental amino acid transport and fetal growth, but whether these effects are mediated directly on the syncytiotrophoblast remains unknown. We hypothesised that glucocorticoids inhibit mechanistic target of rapamycin (mTOR) signaling and insulin-stimulated System A amino acid transport activity in primary human trophoblast (PHT) cells. Syncytialised PHTs, isolated from term placentas (n = 15), were treated with either cortisol (1 μM) or dexamethasone (1 μM), ± insulin (1 nM) for 24 h. Compared to vehicle, dexamethasone increased mRNA expression, but not protein abundance of the mTOR suppressor, regulated in development and DNA damage response 1 (REDD1). Dexamethasone enhanced insulin receptor abundance, activated mTOR complex 1 and 2 signaling and stimulated System A activity, measured by Na+-dependent 14C-methylaminoisobutyric acid uptake. Cortisol also activated mTORC1 without significantly altering insulin receptor or mTORC2 read-outs or System A activity. Both glucocorticoids downregulated expression of the glucocorticoid receptor and the System A transporter genes SLC38A1, SLC38A2 and SLC38A4, without altering SNAT1 or SNAT4 protein abundance. Neither cortisol nor dexamethasone affected System L amino acid transport. Insulin further enhanced mTOR and System A activity, irrespective of glucocorticoid treatment and despite downregulating its own receptor. Contrary to our hypothesis, glucocorticoids do not inhibit mTOR signaling or cause insulin resistance in cultured PHT cells. We speculate that glucocorticoids stimulate System A activity in PHT cells by activating mTOR signaling, which regulates amino acid transporters post-translationally. We conclude that downregulation of placental nutrient transport in vivo following excess maternal glucocorticoids is not mediated by a direct effect on the placenta.
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Affiliation(s)
- O R Vaughan
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - T L Powell
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - T Jansson
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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23
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Chassen S, Jansson T. Complex, coordinated and highly regulated changes in placental signaling and nutrient transport capacity in IUGR. Biochim Biophys Acta Mol Basis Dis 2019; 1866:165373. [PMID: 30684642 DOI: 10.1016/j.bbadis.2018.12.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/20/2018] [Accepted: 12/26/2018] [Indexed: 01/01/2023]
Abstract
The most common cause of intrauterine growth restriction (IUGR) in the developed world is placental insufficiency, a concept often used synonymously with reduced utero-placental and umbilical blood flows. However, placental insufficiency and IUGR are associated with complex, coordinated and highly regulated changes in placental signaling and nutrient transport including inhibition of insulin and mTOR signaling and down-regulation of specific amino acid transporters, Na+/K+-ATPase, the Na+/H+-exchanger, folate and lactate transporters. In contrast, placental glucose transport capacity is unaltered and Ca2+-ATPase activity and the expression of proteins involved in placental lipid transport are increased in IUGR. These findings are not entirely consistent with the traditional view that the placenta is dysfunctional in IUGR, but rather suggest that the placenta adapts to reduce fetal growth in response to an inability of the mother to allocate resources to the fetus. This new model has implications for the understanding of the mechanisms underpinning IUGR and for the development of intervention strategies.
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Affiliation(s)
- Stephanie Chassen
- Department of Pediatrics, Division of Neonatology, University of Colorado, Anschutz Medical Campus, Aurora, USA
| | - Thomas Jansson
- Department of Obstetrics and Gynecology, Division of Reproductive Sciences, University of Colorado, Anschutz Medical Campus, Aurora, USA.
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24
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Rosario FJ, Gupta MB, Myatt L, Powell TL, Glenn JP, Cox L, Jansson T. Mechanistic Target of Rapamycin Complex 1 Promotes the Expression of Genes Encoding Electron Transport Chain Proteins and Stimulates Oxidative Phosphorylation in Primary Human Trophoblast Cells by Regulating Mitochondrial Biogenesis. Sci Rep 2019; 9:246. [PMID: 30670706 PMCID: PMC6343003 DOI: 10.1038/s41598-018-36265-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 11/13/2018] [Indexed: 01/06/2023] Open
Abstract
Trophoblast oxidative phosphorylation provides energy for active transport and protein synthesis, which are critical placental functions influencing fetal growth and long-term health. The molecular mechanisms regulating trophoblast mitochondrial oxidative phosphorylation are largely unknown. We hypothesized that mechanistic Target of Rapamycin Complex 1 (mTORC1) is a positive regulator of key genes encoding Electron Transport Chain (ETC) proteins and stimulates oxidative phosphorylation in trophoblast and that ETC protein expression is down-regulated in placentas of infants with intrauterine growth restriction (IUGR). We silenced raptor (mTORC1 inhibition), rictor (mTORC2 inhibition) or DEPTOR (mTORC1/2 activation) in cultured term primary human trophoblast (PHT) cells. mTORC1 inhibition caused a coordinated down-regulation of 18 genes encoding ETC proteins representing all ETC complexes. Inhibition of mTORC1, but not mTORC2, decreased protein expression of ETC complexes I–IV, mitochondrial basal, ATP coupled and maximal respiration, reserve capacity and proton leak, whereas activation of mTORC1 had the opposite effects. Moreover, placental protein expression of ETC complexes was decreased and positively correlated to mTOR signaling activity in IUGR. By controlling trophoblast ATP production, mTORC1 links nutrient and O2 availability and growth factor signaling to placental function and fetal growth. Reduced placental mTOR activity may impair mitochondrial respiration and contribute to placental insufficiency in IUGR pregnancies.
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Affiliation(s)
- Fredrick J Rosario
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
| | - Madhulika B Gupta
- Children's Health Research Institute and Department of Pediatrics and Biochemistry, University of Western Ontario, London, Ontario, N6A 5C1, Canada
| | - Leslie Myatt
- Department of Obstetrics and Gynecology, Oregon Health and Science University, Portland, USA
| | - Theresa L Powell
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.,Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Jeremy P Glenn
- Department of Genetics, Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Laura Cox
- Department of Genetics, Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA.,Department of Internal Medicine, Section of Molecular Medicine and Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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25
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Reza-López SA, Aguirre-Chacón EO, Sánchez-Ramírez B, Guerrero-Salgado F, Chávez-Corral DV, Levario-Carrillo M. Folate transporter expression in placenta from pregnancies complicated with birth defects. Birth Defects Res 2018; 110:1223-1227. [PMID: 30063111 DOI: 10.1002/bdr2.1356] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 04/23/2018] [Accepted: 05/02/2018] [Indexed: 11/12/2022]
Abstract
BACKGROUND Folate plays a fundamental role for fetal development, participating in cell division, embryogenesis, and fetal growth. The fetus depends on maternal supply of folate across the placenta. The objective of this study was to compare the expression of Folate Receptor-α (FR-α), Reduced Folate Carrier (RFC), and Proton Coupled Folate Transporter (PCFT) in placentas from pregnancies complicated with birth defects (BD) and controls. METHODS Case-control study, including placentas of BD-complicated pregnancies (n = 25) and a control group (n = 25). We determined the placental expression of FR-α, RFC, and PCFT by immunohistochemistry. Optical density was measured to obtain a relative quantification of the expression. RESULTS The expression of PCFT was greater in placentas from pregnancies complicated with BD than in those from the control group (p < .01). The expression of FR-α and RFC was not different between groups. CONCLUSION The expression of PCFT in placentas from BD-complicated pregnancies is increased, possibly as an adaptive response to increase the folate flux at the maternal-fetal interface.
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Affiliation(s)
- Sandra A Reza-López
- Facultad de Medicina y Ciencias Biomédicas, Universidad Autónoma de Chihuahua, Chihuahua, Mexico
| | - Edwin O Aguirre-Chacón
- Facultad de Medicina y Ciencias Biomédicas, Universidad Autónoma de Chihuahua, Chihuahua, Mexico
| | - Blanca Sánchez-Ramírez
- Programa de Maestría en Ciencias en Biotecnología, Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Chihuahua, Mexico
| | - Fabiola Guerrero-Salgado
- Programa de Maestría en Ciencias en Biotecnología, Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Chihuahua, Mexico
| | - Dora V Chávez-Corral
- Facultad de Medicina y Ciencias Biomédicas, Universidad Autónoma de Chihuahua, Chihuahua, Mexico
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26
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Lan X, Field MS, Stover PJ. Cell cycle regulation of folate-mediated one-carbon metabolism. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2018; 10:e1426. [DOI: 10.1002/wsbm.1426] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 04/26/2018] [Accepted: 04/27/2018] [Indexed: 12/25/2022]
Affiliation(s)
- Xu Lan
- Division of Nutritional Sciences; Cornell University; Ithaca New York
| | - Martha S. Field
- Division of Nutritional Sciences; Cornell University; Ithaca New York
| | - Patrick J. Stover
- Division of Nutritional Sciences; Cornell University; Ithaca New York
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27
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Rosario FJ, Nathanielsz PW, Powell TL, Jansson T. Maternal folate deficiency causes inhibition of mTOR signaling, down-regulation of placental amino acid transporters and fetal growth restriction in mice. Sci Rep 2017. [PMID: 28638048 PMCID: PMC5479823 DOI: 10.1038/s41598-017-03888-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Maternal folate deficiency is linked to restricted fetal growth, however the underlying mechanisms remain to be established. Here we tested the hypothesis that mTOR functions as a folate sensor in vivo in mice and that maternal folate deficiency inhibits placental mTOR signaling and amino acid transporter activity and causes fetal growth restriction. Folate deficient mice had lower serum folate (−60%). In late pregnancy, fetal weight in the folate deficient group was decreased (−17%, p < 0.05), whereas placental weight, litter size and crown rump length were unaltered. Maternal folate deficiency inhibited placental mTORC1 and mTORC2 signaling and decreased trophoblast plasma membrane System A and L amino acid transporter activities and transporter isoform expression. Folate deficiency also caused a decrease in phosphorylation of specific functional readouts of mTORC1 and mTORC2 signaling in multiple maternal and fetal tissues. We have identified a novel specific molecular link between maternal folate availability and fetal growth, involving regulation of placental mTOR signaling by folate, resulting in changes in placental nutrient transport. mTOR folate sensing may have broad biological significance because of the critical role of folate in normal cell function and the wide range of disorders, including cancer, that have been linked to folate availability.
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Affiliation(s)
- Fredrick J Rosario
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.
| | - Peter W Nathanielsz
- Department of Animal Science, University of Wyoming, Laramsie, WY, 82071, USA.,Southwest National Primate Research Center, San Antonio, TX, 78249, USA
| | - Theresa L Powell
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.,Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
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28
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Silva E, Rosario FJ, Powell TL, Jansson T. Mechanistic Target of Rapamycin Is a Novel Molecular Mechanism Linking Folate Availability and Cell Function. J Nutr 2017; 147:1237-1242. [PMID: 28592519 DOI: 10.3945/jn.117.248823] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 03/16/2017] [Accepted: 05/11/2017] [Indexed: 12/15/2022] Open
Abstract
Folate deficiency has been linked to a wide range of disorders, including cancer, neural tube defects, and fetal growth restriction. Folate regulates cellular function mediated by its involvement in the synthesis of nucleotides, which are needed for DNA synthesis, and its function as a methyl donor, which is critical for DNA methylation. Here we review current data showing that folate sensing by mechanistic target of rapamycin (mTOR) constitutes a novel and distinct pathway by which folate modulates cell functions such as nutrient transport, protein synthesis, and mitochondrial respiration. The mTOR signaling pathway responds to growth factors and changes in nutrient availability to control cell growth, proliferation, and metabolism. mTOR exists in 2 complexes, mTOR complex (mTORC) 1 and mTORC2, which have distinct upstream regulators and downstream targets. Folate deficiency in pregnant mice caused a marked inhibition of mTORC1 and mTORC2 signaling in multiple maternal and fetal tissues, downregulation of placental amino acid transporters, and fetal growth restriction. In addition, folate deficiency in primary human trophoblast (PHT) cells resulted in inhibition of mTORC1 and mTORC2 signaling and decreased the activity of key amino acid transporters. Folate sensing by mTOR in PHT cells is independent of the accumulation of homocysteine and requires the proton-coupled folate transporter (PCFT; solute carrier 46A1). Furthermore, mTORC1 and mTORC2 regulate trophoblast folate uptake by modulating the cell surface expression of folate receptor α and the reduced folate carrier. These findings, which provide a novel link between folate availability and cell function, growth, and proliferation, may have broad biological significance given the critical role of folate in normal cell function and the multiple diseases that have been associated with decreased or excessive folate availability. Low maternal folate concentrations are linked to restricted fetal growth, and we propose that the underlying mechanisms involve trophoblast mTOR folate sensing resulting in inhibition of mTORC1 and mTORC2 and downregulation of placental amino acid transporters.
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Affiliation(s)
- Elena Silva
- Departments of Obstetrics and Gynecology and
| | | | - Theresa L Powell
- Pediatrics, University of Colorado, Anschutz Medical Campus, Aurora, CO
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29
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Rosario FJ, Powell TL, Jansson T. mTOR folate sensing links folate availability to trophoblast cell function. J Physiol 2017; 595:4189-4206. [PMID: 28374905 DOI: 10.1113/jp272424] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2017] [Accepted: 03/29/2017] [Indexed: 12/20/2022] Open
Abstract
KEY POINTS Folate deficiency during pregnancy is associated with restricted fetal growth, although the underlying mechanisms are poorly understood. Here we show that mechanistic target of rapamycin (mTOR) functions as a folate sensor in primary human trophoblast (PHT) cells. Folate sensing by mTOR in PHT cells involves both mTOR Complex 1 and 2 and requires the proton-coupled folate transporter. We report a previously unknown molecular mechanism by which folate regulates trophoblast cell function. Because mTOR is a positive regulator of placental amino acid transport and mitochondrial function, placental mTOR folate sensing may constitute the mechanistic link between maternal folate status and fetal growth. These findings provide new insight into how folate influences human cell physiology and may have implications for our understanding of how altered folate availability causes diseases such as fetal growth restriction, fetal malformations and cancer. ABSTRACT Folate is a water-soluble B vitamin that is essential for cellular methylation reactions and DNA synthesis and repair. Low maternal folate levels in pregnancy are associated with fetal growth restriction, but the underlying mechanisms are poorly understood. Mechanistic target of rapamycin (mTOR) links nutrient availability to cell growth and function by regulating gene expression and protein translation. Here we show that mTOR functions as a folate sensor in primary human trophoblast (PHT) cells. Folate deficiency in PHT cells caused inhibition of mTOR signalling and decreased the activity of key amino acid transporters. Folate sensing by mTOR in PHT cells involves both mTOR Complex 1 and 2 and requires the proton-coupled folate transporter (PCFT, SLC46A1). The involvement of PCFT in mTOR folate sensing is not dependent on its function as a plasma membrane folate transporter. Increasing levels of homocysteine had no effect on PHT mTOR signalling, suggesting that mTOR senses low folate rather than high homocysteine. In addition, we demonstrate that maternal serum folate is positively correlated to placental mTORC1 and mTORC2 signalling activity in human pregnancy. We have identified a previously unknown molecular link between folate availability and cell function involving PCFT and mTOR signalling. We propose that mTOR folate sensing in trophoblast cells matches placental nutrient transport, and therefore fetal growth, to folate availability. These findings may have implications for our understanding of how altered folate availability causes human diseases such as fetal growth restriction, fetal malformations and cancer.
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Affiliation(s)
- Fredrick J Rosario
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Theresa L Powell
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.,Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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30
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Howell KR, Powell TL. Effects of maternal obesity on placental function and fetal development. Reproduction 2016; 153:R97-R108. [PMID: 27864335 DOI: 10.1530/rep-16-0495] [Citation(s) in RCA: 202] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 11/10/2016] [Accepted: 11/18/2016] [Indexed: 12/11/2022]
Abstract
Obesity has reached epidemic proportions, and pregnancies in obese mothers have increased risk for complications including gestational diabetes, hypertensive disorders, pre-term birth and caesarian section. Children born to obese mothers are at increased risk of obesity and metabolic disease and are susceptible to develop neuropsychiatric and cognitive disorders. Changes in placental function not only play a critical role in the development of pregnancy complications but may also be involved in linking maternal obesity to long-term health risks in the infant. Maternal adipokines, i.e., interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), leptin and adiponectin link maternal nutritional status and adipose tissue metabolism to placental function. Adipokines and metabolic hormones have direct impact on placental function by modulating placental nutrient transport. Nutrient delivery to the fetus is regulated by a complex interaction including insulin signaling, cytokine profile and insulin responsiveness, which is modulated by adiponectin and IL-1β. In addition, obese pregnant women are at risk for hypertension and preeclampsia with reduced placental vascularity and blood flow, which would restrict placental nutrient delivery to the developing fetus. These sometimes opposing signals regulating placental function may contribute to the diversity of short and long-term outcomes observed in pregnant obese women. This review focuses on the changes in adipokines and obesity-related metabolic hormones, how these factors influence placental function and fetal development to contribute to long-term metabolic and behavioral consequences of children born to obese mothers.
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Affiliation(s)
- Kristy R Howell
- Departments of PsychiatryObstetrics/Gynecology and Pediatrics, University of Colorado, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Theresa L Powell
- Departments of PsychiatryObstetrics/Gynecology and Pediatrics, University of Colorado, Anschutz Medical Campus, Aurora, Colorado, USA
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